]> git.saurik.com Git - apple/xnu.git/blobdiff - osfmk/ipc/ipc_kmsg.c
xnu-6153.61.1.tar.gz
[apple/xnu.git] / osfmk / ipc / ipc_kmsg.c
index 4ec900c7b9ea5000e8b4ee1ce1c118c089ace2f0..f1611fc821036fccebd36c445a33bd5a1ce6daf0 100644 (file)
@@ -2,7 +2,7 @@
  * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
- * 
+ *
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in
  * unlawful or unlicensed copies of an Apple operating system, or to
  * circumvent, violate, or enable the circumvention or violation of, any
  * terms of an Apple operating system software license agreement.
- * 
+ *
  * Please obtain a copy of the License at
  * http://www.opensource.apple.com/apsl/ and read it before using this file.
- * 
+ *
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  * Please see the License for the specific language governing rights and
  * limitations under the License.
- * 
+ *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 /*
  * @OSF_COPYRIGHT@
  */
-/* 
+/*
  * Mach Operating System
  * Copyright (c) 1991,1990,1989 Carnegie Mellon University
  * All Rights Reserved.
- * 
+ *
  * Permission to use, copy, modify and distribute this software and its
  * documentation is hereby granted, provided that both the copyright
  * notice and this permission notice appear in all copies of the
  * software, derivative works or modified versions, and any portions
  * thereof, and that both notices appear in supporting documentation.
- * 
+ *
  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
- * 
+ *
  * Carnegie Mellon requests users of this software to return to
- * 
+ *
  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  *  School of Computer Science
  *  Carnegie Mellon University
  *  Pittsburgh PA 15213-3890
- * 
+ *
  * any improvements or extensions that they make and grant Carnegie Mellon
  * the rights to redistribute these changes.
  */
@@ -94,7 +94,9 @@
 #include <kern/cpu_data.h>
 #include <kern/policy_internal.h>
 
-#include <machine/machlimits.h>
+#include <pthread/priority_private.h>
+
+#include <machine/limits.h>
 
 #include <vm/vm_map.h>
 #include <vm/vm_object.h>
 
 #pragma pack(4)
 
-typedef        struct 
-{
-  mach_msg_bits_t      msgh_bits;
-  mach_msg_size_t      msgh_size;
-  mach_port_name_t     msgh_remote_port;
-  mach_port_name_t     msgh_local_port;
-  mach_port_name_t     msgh_voucher_port;
-  mach_msg_id_t                msgh_id;
+typedef struct{
+       mach_msg_bits_t       msgh_bits;
+       mach_msg_size_t       msgh_size;
+       mach_port_name_t      msgh_remote_port;
+       mach_port_name_t      msgh_local_port;
+       mach_port_name_t      msgh_voucher_port;
+       mach_msg_id_t         msgh_id;
 } mach_msg_legacy_header_t;
 
-typedef struct
-{
-        mach_msg_legacy_header_t       header;
-        mach_msg_body_t         body;
+typedef struct{
+       mach_msg_legacy_header_t       header;
+       mach_msg_body_t         body;
 } mach_msg_legacy_base_t;
 
-typedef struct
-{
-  mach_port_name_t                             name;
-  mach_msg_size_t                              pad1;
-  uint32_t                                             pad2 : 16;
-  mach_msg_type_name_t                 disposition : 8;
-  mach_msg_descriptor_type_t   type : 8;
+typedef struct{
+       mach_port_name_t                              name;
+       mach_msg_size_t                               pad1;
+       uint32_t                                              pad2 : 16;
+       mach_msg_type_name_t                  disposition : 8;
+       mach_msg_descriptor_type_t    type : 8;
 } mach_msg_legacy_port_descriptor_t;
 
 
-typedef union
-{
-  mach_msg_legacy_port_descriptor_t                    port;
-  mach_msg_ool_descriptor32_t          out_of_line32;
-  mach_msg_ool_ports_descriptor32_t    ool_ports32;
-  mach_msg_type_descriptor_t                   type;
+typedef union{
+       mach_msg_legacy_port_descriptor_t                     port;
+       mach_msg_ool_descriptor32_t           out_of_line32;
+       mach_msg_ool_ports_descriptor32_t     ool_ports32;
+       mach_msg_guarded_port_descriptor32_t  guarded_port32;
+       mach_msg_type_descriptor_t                    type;
 } mach_msg_legacy_descriptor_t;
 
 #pragma pack()
@@ -182,49 +181,49 @@ typedef union
 
 #if DEBUG_MSGS_K64
 extern void ipc_pset_print64(
-                       ipc_pset_t      pset);
+       ipc_pset_t      pset);
 
-extern void    ipc_kmsg_print64(
-                       ipc_kmsg_t      kmsg,
-                       const char      *str);
+extern void     ipc_kmsg_print64(
+       ipc_kmsg_t      kmsg,
+       const char      *str);
 
-extern void    ipc_msg_print64(
-               mach_msg_header_t       *msgh);
+extern void     ipc_msg_print64(
+       mach_msg_header_t       *msgh);
 
 extern ipc_port_t ipc_name_to_data64(
-                       task_t                  task,
-                       mach_port_name_t        name);
+       task_t                  task,
+       mach_port_name_t        name);
 
 /*
  * Forward declarations
  */
 void ipc_msg_print_untyped64(
-       mach_msg_body_t         *body);
+       mach_msg_body_t         *body);
 
 const char * ipc_type_name64(
-       int             type_name,
-       boolean_t       received);
+       int             type_name,
+       boolean_t       received);
 
 void ipc_print_type_name64(
-       int     type_name);
+       int     type_name);
 
 const char *
 msgh_bit_decode64(
-       mach_msg_bits_t bit);
+       mach_msg_bits_t bit);
 
 const char *
 mm_copy_options_string64(
-       mach_msg_copy_options_t option);
+       mach_msg_copy_options_t option);
 
 void db_print_msg_uid64(mach_msg_header_t *);
 
 static void
 ipc_msg_body_print64(void *body, int size)
 {
-       uint32_t        *word = (uint32_t *) body;
-       uint32_t        *end  = (uint32_t *)(((uintptr_t) body) + size
-                                               - sizeof(mach_msg_header_t));
-       int             i;
+       uint32_t        *word = (uint32_t *) body;
+       uint32_t        *end  = (uint32_t *)(((uintptr_t) body) + size
+           - sizeof(mach_msg_header_t));
+       int             i;
 
        kprintf("  body(%p-%p):\n    %p: ", body, end, word);
        for (;;) {
@@ -233,7 +232,7 @@ ipc_msg_body_print64(void *body, int size)
                                kprintf("\n");
                                return;
                        }
-                       kprintf("%08x ", *word); 
+                       kprintf("%08x ", *word);
                }
                kprintf("\n    %p: ", word);
        }
@@ -242,51 +241,51 @@ ipc_msg_body_print64(void *body, int size)
 
 const char *
 ipc_type_name64(
-       int             type_name,
-       boolean_t       received)
+       int             type_name,
+       boolean_t       received)
 {
        switch (type_name) {
-               case MACH_MSG_TYPE_PORT_NAME:
+       case MACH_MSG_TYPE_PORT_NAME:
                return "port_name";
-               
-               case MACH_MSG_TYPE_MOVE_RECEIVE:
+
+       case MACH_MSG_TYPE_MOVE_RECEIVE:
                if (received) {
                        return "port_receive";
                } else {
                        return "move_receive";
                }
-               
-               case MACH_MSG_TYPE_MOVE_SEND:
+
+       case MACH_MSG_TYPE_MOVE_SEND:
                if (received) {
                        return "port_send";
                } else {
                        return "move_send";
                }
-               
-               case MACH_MSG_TYPE_MOVE_SEND_ONCE:
+
+       case MACH_MSG_TYPE_MOVE_SEND_ONCE:
                if (received) {
                        return "port_send_once";
                } else {
                        return "move_send_once";
                }
-               
-               case MACH_MSG_TYPE_COPY_SEND:
+
+       case MACH_MSG_TYPE_COPY_SEND:
                return "copy_send";
-               
-               case MACH_MSG_TYPE_MAKE_SEND:
+
+       case MACH_MSG_TYPE_MAKE_SEND:
                return "make_send";
-               
-               case MACH_MSG_TYPE_MAKE_SEND_ONCE:
+
+       case MACH_MSG_TYPE_MAKE_SEND_ONCE:
                return "make_send_once";
-               
-               default:
+
+       default:
                return (char *) 0;
        }
 }
-               
+
 void
 ipc_print_type_name64(
-       int     type_name)
+       int     type_name)
 {
        const char *name = ipc_type_name64(type_name, TRUE);
        if (name) {
@@ -301,26 +300,26 @@ ipc_print_type_name64(
  */
 void
 ipc_kmsg_print64(
-       ipc_kmsg_t      kmsg,
-       const char      *str)
+       ipc_kmsg_t      kmsg,
+       const char      *str)
 {
        kprintf("%s kmsg=%p:\n", str, kmsg);
        kprintf("  next=%p, prev=%p, size=%d",
-               kmsg->ikm_next,
-               kmsg->ikm_prev,
-               kmsg->ikm_size);
+           kmsg->ikm_next,
+           kmsg->ikm_prev,
+           kmsg->ikm_size);
        kprintf("\n");
        ipc_msg_print64(kmsg->ikm_header);
 }
 
 const char *
 msgh_bit_decode64(
-       mach_msg_bits_t bit)
+       mach_msg_bits_t bit)
 {
        switch (bit) {
-           case MACH_MSGH_BITS_COMPLEX:        return "complex";
-           case MACH_MSGH_BITS_CIRCULAR:       return "circular";
-           default:                            return (char *) 0;
+       case MACH_MSGH_BITS_COMPLEX:        return "complex";
+       case MACH_MSGH_BITS_CIRCULAR:       return "circular";
+       default:                            return (char *) 0;
        }
 }
 
@@ -329,35 +328,37 @@ msgh_bit_decode64(
  */
 void
 ipc_msg_print64(
-       mach_msg_header_t       *msgh)
+       mach_msg_header_t       *msgh)
 {
-       mach_msg_bits_t mbits;
-       unsigned int    bit, i;
-       const char      *bit_name;
-       int             needs_comma;
+       mach_msg_bits_t mbits;
+       unsigned int    bit, i;
+       const char      *bit_name;
+       int             needs_comma;
 
        mbits = msgh->msgh_bits;
        kprintf("  msgh_bits=0x%x: l=0x%x,r=0x%x\n",
-               mbits,
-               MACH_MSGH_BITS_LOCAL(msgh->msgh_bits),
-               MACH_MSGH_BITS_REMOTE(msgh->msgh_bits));
+           mbits,
+           MACH_MSGH_BITS_LOCAL(msgh->msgh_bits),
+           MACH_MSGH_BITS_REMOTE(msgh->msgh_bits));
 
        mbits = MACH_MSGH_BITS_OTHER(mbits) & MACH_MSGH_BITS_USED;
        kprintf("  decoded bits:  ");
        needs_comma = 0;
        for (i = 0, bit = 1; i < sizeof(mbits) * 8; ++i, bit <<= 1) {
-               if ((mbits & bit) == 0)
+               if ((mbits & bit) == 0) {
                        continue;
+               }
                bit_name = msgh_bit_decode64((mach_msg_bits_t)bit);
-               if (bit_name)
+               if (bit_name) {
                        kprintf("%s%s", needs_comma ? "," : "", bit_name);
-               else
+               } else {
                        kprintf("%sunknown(0x%x),", needs_comma ? "," : "", bit);
+               }
                ++needs_comma;
        }
        if (msgh->msgh_bits & ~MACH_MSGH_BITS_USED) {
                kprintf("%sunused=0x%x,", needs_comma ? "," : "",
-                      msgh->msgh_bits & ~MACH_MSGH_BITS_USED);
+                   msgh->msgh_bits & ~MACH_MSGH_BITS_USED);
        }
        kprintf("\n");
 
@@ -372,7 +373,7 @@ ipc_msg_print64(
 
        if (msgh->msgh_local_port) {
                kprintf("%slocal=%p(", needs_comma ? "," : "",
-                      msgh->msgh_local_port);
+                   msgh->msgh_local_port);
                ipc_print_type_name64(MACH_MSGH_BITS_LOCAL(msgh->msgh_bits));
                kprintf(")\n");
        } else {
@@ -380,10 +381,10 @@ ipc_msg_print64(
        }
 
        kprintf("  msgh_id=%d, size=%d\n",
-               msgh->msgh_id,
-               msgh->msgh_size);
+           msgh->msgh_id,
+           msgh->msgh_size);
 
-       if (mbits & MACH_MSGH_BITS_COMPLEX) {   
+       if (mbits & MACH_MSGH_BITS_COMPLEX) {
                ipc_msg_print_untyped64((mach_msg_body_t *) (msgh + 1));
        }
 
@@ -393,27 +394,27 @@ ipc_msg_print64(
 
 const char *
 mm_copy_options_string64(
-       mach_msg_copy_options_t option)
+       mach_msg_copy_options_t option)
 {
-       const char      *name;
+       const char      *name;
 
        switch (option) {
-           case MACH_MSG_PHYSICAL_COPY:
+       case MACH_MSG_PHYSICAL_COPY:
                name = "PHYSICAL";
                break;
-           case MACH_MSG_VIRTUAL_COPY:
+       case MACH_MSG_VIRTUAL_COPY:
                name = "VIRTUAL";
                break;
-           case MACH_MSG_OVERWRITE:
+       case MACH_MSG_OVERWRITE:
                name = "OVERWRITE(DEPRECATED)";
                break;
-           case MACH_MSG_ALLOCATE:
+       case MACH_MSG_ALLOCATE:
                name = "ALLOCATE";
                break;
-           case MACH_MSG_KALLOC_COPY_T:
+       case MACH_MSG_KALLOC_COPY_T:
                name = "KALLOC_COPY_T";
                break;
-           default:
+       default:
                name = "unknown";
                break;
        }
@@ -422,128 +423,134 @@ mm_copy_options_string64(
 
 void
 ipc_msg_print_untyped64(
-       mach_msg_body_t         *body)
+       mach_msg_body_t         *body)
 {
-    mach_msg_descriptor_t      *saddr, *send;
-    mach_msg_descriptor_type_t type;
+       mach_msg_descriptor_t       *saddr, *send;
+       mach_msg_descriptor_type_t  type;
 
-    kprintf("  %d descriptors: \n", body->msgh_descriptor_count);
+       kprintf("  %d descriptors: \n", body->msgh_descriptor_count);
 
-    saddr = (mach_msg_descriptor_t *) (body + 1);
-    send = saddr + body->msgh_descriptor_count;
+       saddr = (mach_msg_descriptor_t *) (body + 1);
+       send = saddr + body->msgh_descriptor_count;
 
-    for ( ; saddr < send; saddr++ ) {
-       
-       type = saddr->type.type;
+       for (; saddr < send; saddr++) {
+               type = saddr->type.type;
 
-       switch (type) {
-           
-           case MACH_MSG_PORT_DESCRIPTOR: {
-               mach_msg_port_descriptor_t *dsc;
+               switch (type) {
+               case MACH_MSG_PORT_DESCRIPTOR: {
+                       mach_msg_port_descriptor_t *dsc;
 
-               dsc = &saddr->port;
-               kprintf("    PORT name = %p disp = ", dsc->name);
-               ipc_print_type_name64(dsc->disposition);
-               kprintf("\n");
-               break;
-           }
-           case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
-           case MACH_MSG_OOL_DESCRIPTOR: {
-               mach_msg_ool_descriptor_t *dsc;
-               
-               dsc = (mach_msg_ool_descriptor_t *) &saddr->out_of_line;
-               kprintf("    OOL%s addr = %p size = 0x%x copy = %s %s\n",
-                       type == MACH_MSG_OOL_DESCRIPTOR ? "" : " VOLATILE",
-                       dsc->address, dsc->size,
-                       mm_copy_options_string64(dsc->copy),
-                       dsc->deallocate ? "DEALLOC" : "");
-               break;
-           } 
-           case MACH_MSG_OOL_PORTS_DESCRIPTOR : {
-               mach_msg_ool_ports_descriptor_t *dsc;
-
-               dsc = (mach_msg_ool_ports_descriptor_t *) &saddr->ool_ports;
-
-               kprintf("    OOL_PORTS addr = %p count = 0x%x ",
-                         dsc->address, dsc->count);
-               kprintf("disp = ");
-               ipc_print_type_name64(dsc->disposition);
-               kprintf(" copy = %s %s\n",
-                      mm_copy_options_string64(dsc->copy),
-                      dsc->deallocate ? "DEALLOC" : "");
-               break;
-           }
+                       dsc = &saddr->port;
+                       kprintf("    PORT name = %p disp = ", dsc->name);
+                       ipc_print_type_name64(dsc->disposition);
+                       kprintf("\n");
+                       break;
+               }
+               case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
+               case MACH_MSG_OOL_DESCRIPTOR: {
+                       mach_msg_ool_descriptor_t *dsc;
+
+                       dsc = (mach_msg_ool_descriptor_t *) &saddr->out_of_line;
+                       kprintf("    OOL%s addr = %p size = 0x%x copy = %s %s\n",
+                           type == MACH_MSG_OOL_DESCRIPTOR ? "" : " VOLATILE",
+                           dsc->address, dsc->size,
+                           mm_copy_options_string64(dsc->copy),
+                           dsc->deallocate ? "DEALLOC" : "");
+                       break;
+               }
+               case MACH_MSG_OOL_PORTS_DESCRIPTOR: {
+                       mach_msg_ool_ports_descriptor_t *dsc;
+
+                       dsc = (mach_msg_ool_ports_descriptor_t *) &saddr->ool_ports;
+
+                       kprintf("    OOL_PORTS addr = %p count = 0x%x ",
+                           dsc->address, dsc->count);
+                       kprintf("disp = ");
+                       ipc_print_type_name64(dsc->disposition);
+                       kprintf(" copy = %s %s\n",
+                           mm_copy_options_string64(dsc->copy),
+                           dsc->deallocate ? "DEALLOC" : "");
+                       break;
+               }
+               case MACH_MSG_GUARDED_PORT_DESCRIPTOR: {
+                       mach_msg_guarded_port_descriptor_t *dsc;
 
-           default: {
-               kprintf("    UNKNOWN DESCRIPTOR 0x%x\n", type);
-               break;
-           }
+                       dsc = (mach_msg_guarded_port_descriptor_t *)&saddr->guarded_port;
+                       kprintf("    GUARDED_PORT name = %p flags = 0x%x disp = ", dsc->name, dsc->flags);
+                       ipc_print_type_name64(dsc->disposition);
+                       kprintf("\n");
+                       break;
+               }
+               default: {
+                       kprintf("    UNKNOWN DESCRIPTOR 0x%x\n", type);
+                       break;
+               }
+               }
        }
-    }
 }
 
-#define        DEBUG_IPC_KMSG_PRINT(kmsg,string)       \
-       __unreachable_ok_push   \
-       if (DEBUG_KPRINT_SYSCALL_PREDICATE(DEBUG_KPRINT_SYSCALL_IPC_MASK)) {    \
-               ipc_kmsg_print64(kmsg, string); \
-       }       \
+#define DEBUG_IPC_KMSG_PRINT(kmsg, string)       \
+       __unreachable_ok_push   \
+       if (DEBUG_KPRINT_SYSCALL_PREDICATE(DEBUG_KPRINT_SYSCALL_IPC_MASK)) {    \
+               ipc_kmsg_print64(kmsg, string); \
+       }       \
        __unreachable_ok_pop
 
-#define        DEBUG_IPC_MSG_BODY_PRINT(body,size)     \
-       __unreachable_ok_push   \
-       if (DEBUG_KPRINT_SYSCALL_PREDICATE(DEBUG_KPRINT_SYSCALL_IPC_MASK)) {    \
-               ipc_msg_body_print64(body,size);\
-       }       \
+#define DEBUG_IPC_MSG_BODY_PRINT(body, size)     \
+       __unreachable_ok_push   \
+       if (DEBUG_KPRINT_SYSCALL_PREDICATE(DEBUG_KPRINT_SYSCALL_IPC_MASK)) {    \
+               ipc_msg_body_print64(body,size);\
+       }       \
        __unreachable_ok_pop
 #else /* !DEBUG_MSGS_K64 */
-#define DEBUG_IPC_KMSG_PRINT(kmsg,string)
-#define        DEBUG_IPC_MSG_BODY_PRINT(body,size)
+#define DEBUG_IPC_KMSG_PRINT(kmsg, string)
+#define DEBUG_IPC_MSG_BODY_PRINT(body, size)
 #endif  /* !DEBUG_MSGS_K64 */
 
-extern vm_map_t                ipc_kernel_copy_map;
-extern vm_size_t       ipc_kmsg_max_space;
-extern vm_size_t       ipc_kmsg_max_vm_space;
-extern vm_size_t       ipc_kmsg_max_body_space;
-extern vm_size_t       msg_ool_size_small;
+extern vm_map_t         ipc_kernel_copy_map;
+extern vm_size_t        ipc_kmsg_max_space;
+extern vm_size_t        ipc_kmsg_max_vm_space;
+extern vm_size_t        ipc_kmsg_max_body_space;
+extern vm_size_t        msg_ool_size_small;
 
-#define MSG_OOL_SIZE_SMALL     msg_ool_size_small
+#define MSG_OOL_SIZE_SMALL      msg_ool_size_small
 
 #if defined(__LP64__)
-#define MAP_SIZE_DIFFERS(map)  (map->max_offset < MACH_VM_MAX_ADDRESS)
-#define OTHER_OOL_DESCRIPTOR   mach_msg_ool_descriptor32_t
-#define OTHER_OOL_PORTS_DESCRIPTOR     mach_msg_ool_ports_descriptor32_t
+#define MAP_SIZE_DIFFERS(map)   (map->max_offset < MACH_VM_MAX_ADDRESS)
+#define OTHER_OOL_DESCRIPTOR    mach_msg_ool_descriptor32_t
+#define OTHER_OOL_PORTS_DESCRIPTOR      mach_msg_ool_ports_descriptor32_t
 #else
-#define MAP_SIZE_DIFFERS(map)  (map->max_offset > VM_MAX_ADDRESS)
-#define OTHER_OOL_DESCRIPTOR   mach_msg_ool_descriptor64_t
-#define OTHER_OOL_PORTS_DESCRIPTOR     mach_msg_ool_ports_descriptor64_t
+#define MAP_SIZE_DIFFERS(map)   (map->max_offset > VM_MAX_ADDRESS)
+#define OTHER_OOL_DESCRIPTOR    mach_msg_ool_descriptor64_t
+#define OTHER_OOL_PORTS_DESCRIPTOR      mach_msg_ool_ports_descriptor64_t
 #endif
 
-#define DESC_SIZE_ADJUSTMENT   ((mach_msg_size_t)(sizeof(mach_msg_ool_descriptor64_t) - \
-                                sizeof(mach_msg_ool_descriptor32_t)))
+#define DESC_SIZE_ADJUSTMENT    ((mach_msg_size_t)(sizeof(mach_msg_ool_descriptor64_t) - \
+                                sizeof(mach_msg_ool_descriptor32_t)))
 
 /* scatter list macros */
 
-#define SKIP_PORT_DESCRIPTORS(s, c)                                    \
-MACRO_BEGIN                                                            \
-       if ((s) != MACH_MSG_DESCRIPTOR_NULL) {                          \
-               while ((c) > 0) {                                       \
-                       if ((s)->type.type != MACH_MSG_PORT_DESCRIPTOR) \
-                               break;                                  \
-                       (s)++; (c)--;                                   \
-               }                                                       \
-               if (c == 0)                                             \
-                       (s) = MACH_MSG_DESCRIPTOR_NULL;                 \
-       }                                                               \
+#define SKIP_PORT_DESCRIPTORS(s, c)                                     \
+MACRO_BEGIN                                                             \
+       if ((s) != MACH_MSG_DESCRIPTOR_NULL) {                          \
+               while ((c) > 0) {                                       \
+                       if ((s)->type.type != MACH_MSG_PORT_DESCRIPTOR) \
+                               break;                                  \
+                       (s)++; (c)--;                                   \
+               }                                                       \
+               if (c == 0)                                             \
+                       (s) = MACH_MSG_DESCRIPTOR_NULL;                 \
+       }                                                               \
 MACRO_END
 
-#define INCREMENT_SCATTER(s, c, d)                                     \
-MACRO_BEGIN                                                            \
-       if ((s) != MACH_MSG_DESCRIPTOR_NULL) {                          \
-           s = (d) ? (mach_msg_descriptor_t *)                         \
-               ((OTHER_OOL_DESCRIPTOR *)(s) + 1) :                     \
-               (s + 1);                                                \
-               (c)--;                                                  \
-       }                                                               \
+#define INCREMENT_SCATTER(s, c, d)                                      \
+MACRO_BEGIN                                                             \
+       if ((s) != MACH_MSG_DESCRIPTOR_NULL) {                          \
+           s = (d) ? (mach_msg_descriptor_t *)                         \
+               ((OTHER_OOL_DESCRIPTOR *)(s) + 1) :                     \
+               (s + 1);                                                \
+               (c)--;                                                  \
+       }                                                               \
 MACRO_END
 
 #define KMSG_TRACE_FLAG_TRACED     0x000001
@@ -570,8 +577,9 @@ MACRO_END
 #define KMSG_TRACE_FLAG_TIMER      0x200000
 #define KMSG_TRACE_FLAG_SEMA       0x400000
 #define KMSG_TRACE_FLAG_DTMPOWNER  0x800000
+#define KMSG_TRACE_FLAG_GUARDED_DESC 0x1000000
 
-#define KMSG_TRACE_FLAGS_MASK      0xffffff
+#define KMSG_TRACE_FLAGS_MASK      0x1ffffff
 #define KMSG_TRACE_FLAGS_SHIFT     8
 
 #define KMSG_TRACE_PORTS_MASK      0xff
@@ -579,10 +587,10 @@ MACRO_END
 
 #if (KDEBUG_LEVEL >= KDEBUG_LEVEL_STANDARD)
 #include <stdint.h>
-extern boolean_t kdebug_debugid_enabled(uint32_t debugid);
 
-void ipc_kmsg_trace_send(ipc_kmsg_t kmsg,
-                        mach_msg_option_t option)
+void
+ipc_kmsg_trace_send(ipc_kmsg_t kmsg,
+    mach_msg_option_t option)
 {
        task_t send_task = TASK_NULL;
        ipc_port_t dst_port, src_port;
@@ -592,7 +600,7 @@ void ipc_kmsg_trace_send(ipc_kmsg_t kmsg,
 
        int kotype = 0;
        uint32_t msg_size = 0;
-       uint32_t msg_flags = KMSG_TRACE_FLAG_TRACED;
+       uint64_t msg_flags = KMSG_TRACE_FLAG_TRACED;
        uint32_t num_ports = 0;
        uint32_t send_pid, dst_pid;
 
@@ -602,35 +610,43 @@ void ipc_kmsg_trace_send(ipc_kmsg_t kmsg,
         * significant amount of processing (and a port lock hold) in
         * the non-tracing case.
         */
-       if (__probable((kdebug_enable & KDEBUG_TRACE) == 0))
+       if (__probable((kdebug_enable & KDEBUG_TRACE) == 0)) {
                return;
-       if (!kdebug_debugid_enabled(MACHDBG_CODE(DBG_MACH_IPC,MACH_IPC_KMSG_INFO)))
+       }
+       if (!kdebug_debugid_enabled(MACHDBG_CODE(DBG_MACH_IPC, MACH_IPC_KMSG_INFO))) {
                return;
+       }
 
        msg = kmsg->ikm_header;
 
-       dst_port = (ipc_port_t)(msg->msgh_remote_port);
-       if (!IPC_PORT_VALID(dst_port))
+       dst_port = msg->msgh_remote_port;
+       if (!IPC_PORT_VALID(dst_port)) {
                return;
+       }
 
        /*
         * Message properties / options
         */
-       if ((option & (MACH_SEND_MSG|MACH_RCV_MSG)) == (MACH_SEND_MSG|MACH_RCV_MSG))
+       if ((option & (MACH_SEND_MSG | MACH_RCV_MSG)) == (MACH_SEND_MSG | MACH_RCV_MSG)) {
                msg_flags |= KMSG_TRACE_FLAG_SNDRCV;
+       }
 
        if (msg->msgh_id >= is_iokit_subsystem.start &&
-           msg->msgh_id < is_iokit_subsystem.end + 100)
+           msg->msgh_id < is_iokit_subsystem.end + 100) {
                msg_flags |= KMSG_TRACE_FLAG_IOKIT;
+       }
        /* magic XPC checkin message id (XPC_MESSAGE_ID_CHECKIN) from libxpc */
-       else if (msg->msgh_id == 0x77303074u /* w00t */)
+       else if (msg->msgh_id == 0x77303074u /* w00t */) {
                msg_flags |= KMSG_TRACE_FLAG_CHECKIN;
+       }
 
-       if (msg->msgh_bits & MACH_MSGH_BITS_RAISEIMP)
+       if (msg->msgh_bits & MACH_MSGH_BITS_RAISEIMP) {
                msg_flags |= KMSG_TRACE_FLAG_RAISEIMP;
+       }
 
-       if (unsafe_convert_port_to_voucher(kmsg->ikm_voucher))
+       if (unsafe_convert_port_to_voucher(kmsg->ikm_voucher)) {
                msg_flags |= KMSG_TRACE_FLAG_VOUCHER;
+       }
 
        /*
         * Sending task / port
@@ -639,20 +655,23 @@ void ipc_kmsg_trace_send(ipc_kmsg_t kmsg,
        send_pid = task_pid(send_task);
 
        if (send_pid != 0) {
-               if (task_is_daemon(send_task))
+               if (task_is_daemon(send_task)) {
                        msg_flags |= KMSG_TRACE_FLAG_DAEMON_SRC;
-               else if (task_is_app(send_task))
+               } else if (task_is_app(send_task)) {
                        msg_flags |= KMSG_TRACE_FLAG_APP_SRC;
+               }
        }
 
        is_task_64bit = (send_task->map->max_offset > VM_MAX_ADDRESS);
-       if (is_task_64bit)
+       if (is_task_64bit) {
                msg_flags |= KMSG_TRACE_FLAG_SND64;
+       }
 
-       src_port = (ipc_port_t)(msg->msgh_local_port);
+       src_port = msg->msgh_local_port;
        if (src_port) {
-               if (src_port->ip_messages.imq_qlimit != MACH_PORT_QLIMIT_DEFAULT)
+               if (src_port->ip_messages.imq_qlimit != MACH_PORT_QLIMIT_DEFAULT) {
                        msg_flags |= KMSG_TRACE_FLAG_SRC_NDFLTQ;
+               }
                switch (MACH_MSGH_BITS_LOCAL(msg->msgh_bits)) {
                case MACH_MSG_TYPE_MOVE_SEND_ONCE:
                        msg_flags |= KMSG_TRACE_FLAG_SRC_SONCE;
@@ -674,10 +693,11 @@ void ipc_kmsg_trace_send(ipc_kmsg_t kmsg,
                dst_pid = (uint32_t)0xfffffff0;
        } else if (dst_port->ip_tempowner) {
                msg_flags |= KMSG_TRACE_FLAG_DTMPOWNER;
-               if (IIT_NULL != dst_port->ip_imp_task)
+               if (IIT_NULL != dst_port->ip_imp_task) {
                        dst_pid = task_pid(dst_port->ip_imp_task->iit_task);
-               else
+               } else {
                        dst_pid = (uint32_t)0xfffffff1;
+               }
        } else if (dst_port->ip_receiver_name == MACH_PORT_NULL) {
                /* dst_port is otherwise in-transit */
                dst_pid = (uint32_t)0xfffffff2;
@@ -689,10 +709,11 @@ void ipc_kmsg_trace_send(ipc_kmsg_t kmsg,
                        dst_space = dst_port->ip_receiver;
                        if (dst_space && is_active(dst_space)) {
                                dst_pid = task_pid(dst_space->is_task);
-                               if (task_is_daemon(dst_space->is_task))
+                               if (task_is_daemon(dst_space->is_task)) {
                                        msg_flags |= KMSG_TRACE_FLAG_DAEMON_DST;
-                               else if (task_is_app(dst_space->is_task))
+                               } else if (task_is_app(dst_space->is_task)) {
                                        msg_flags |= KMSG_TRACE_FLAG_APP_DST;
+                               }
                        } else {
                                /* receiving task is being torn down */
                                dst_pid = (uint32_t)0xfffffff3;
@@ -700,10 +721,12 @@ void ipc_kmsg_trace_send(ipc_kmsg_t kmsg,
                }
        }
 
-       if (dst_port->ip_messages.imq_qlimit != MACH_PORT_QLIMIT_DEFAULT)
+       if (dst_port->ip_messages.imq_qlimit != MACH_PORT_QLIMIT_DEFAULT) {
                msg_flags |= KMSG_TRACE_FLAG_DST_NDFLTQ;
-       if (imq_full(&dst_port->ip_messages))
+       }
+       if (imq_full(&dst_port->ip_messages)) {
                msg_flags |= KMSG_TRACE_FLAG_DSTQFULL;
+       }
 
        kotype = ip_kotype(dst_port);
 
@@ -720,14 +743,15 @@ void ipc_kmsg_trace_send(ipc_kmsg_t kmsg,
        case IKOT_MASTER_DEVICE:
        case IKOT_IOKIT_CONNECT:
        case IKOT_IOKIT_OBJECT:
-       case IKOT_IOKIT_SPARE:
+       case IKOT_IOKIT_IDENT:
+       case IKOT_UEXT_OBJECT:
                msg_flags |= KMSG_TRACE_FLAG_IOKIT;
                break;
        default:
                break;
        }
 
-       switch(MACH_MSGH_BITS_REMOTE(msg->msgh_bits)) {
+       switch (MACH_MSGH_BITS_REMOTE(msg->msgh_bits)) {
        case MACH_MSG_TYPE_PORT_SEND_ONCE:
                msg_flags |= KMSG_TRACE_FLAG_DST_SONCE;
                break;
@@ -753,15 +777,17 @@ void ipc_kmsg_trace_send(ipc_kmsg_t kmsg,
                kern_dsc = (mach_msg_descriptor_t *)(msg_body + 1);
 
                /* this is gross: see ipc_kmsg_copyin_body()... */
-               if (!is_task_64bit)
+               if (!is_task_64bit) {
                        msg_size -= (dsc_count * 12);
+               }
 
                for (int i = 0; i < dsc_count; i++) {
                        switch (kern_dsc[i].type.type) {
                        case MACH_MSG_PORT_DESCRIPTOR:
                                num_ports++;
-                               if (is_task_64bit)
+                               if (is_task_64bit) {
                                        msg_size -= 12;
+                               }
                                break;
                        case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
                        case MACH_MSG_OOL_DESCRIPTOR: {
@@ -771,22 +797,31 @@ void ipc_kmsg_trace_send(ipc_kmsg_t kmsg,
                                msg_size += dsc->size;
                                if ((dsc->size >= MSG_OOL_SIZE_SMALL) &&
                                    (dsc->copy == MACH_MSG_PHYSICAL_COPY) &&
-                                   !dsc->deallocate)
+                                   !dsc->deallocate) {
                                        msg_flags |= KMSG_TRACE_FLAG_PCPY;
-                               else if (dsc->size <= MSG_OOL_SIZE_SMALL)
+                               } else if (dsc->size <= MSG_OOL_SIZE_SMALL) {
                                        msg_flags |= KMSG_TRACE_FLAG_PCPY;
-                               else
+                               } else {
                                        msg_flags |= KMSG_TRACE_FLAG_VCPY;
-                               if (is_task_64bit)
+                               }
+                               if (is_task_64bit) {
                                        msg_size -= 16;
-                               } break;
+                               }
+                       } break;
                        case MACH_MSG_OOL_PORTS_DESCRIPTOR: {
-                               mach_msg_ool_ports_descriptor_t *dsc;
+                               mach_msg_ool_ports_descriptor_t *dsc;
                                dsc = (mach_msg_ool_ports_descriptor_t *)&kern_dsc[i];
                                num_ports += dsc->count;
-                               if (is_task_64bit)
+                               if (is_task_64bit) {
+                                       msg_size -= 16;
+                               }
+                       } break;
+                       case MACH_MSG_GUARDED_PORT_DESCRIPTOR:
+                               num_ports++;
+                               msg_flags |= KMSG_TRACE_FLAG_GUARDED_DESC;
+                               if (is_task_64bit) {
                                        msg_size -= 16;
-                               } break;
+                               }
                        default:
                                break;
                        }
@@ -797,9 +832,9 @@ void ipc_kmsg_trace_send(ipc_kmsg_t kmsg,
         * Trailer contents
         */
        trailer = (mach_msg_trailer_t *)((vm_offset_t)msg +
-                                        (vm_offset_t)msg->msgh_size);
+           round_msg((vm_offset_t)msg->msgh_size));
        if (trailer->msgh_trailer_size <= sizeof(mach_msg_security_trailer_t)) {
-               extern security_token_t KERNEL_SECURITY_TOKEN;
+               extern const security_token_t KERNEL_SECURITY_TOKEN;
                mach_msg_security_trailer_t *strailer;
                strailer = (mach_msg_security_trailer_t *)trailer;
                /*
@@ -807,53 +842,77 @@ void ipc_kmsg_trace_send(ipc_kmsg_t kmsg,
                 * like self-talk because the sending port is not reset.
                 */
                if (memcmp(&strailer->msgh_sender,
-                          &KERNEL_SECURITY_TOKEN,
-                          sizeof(KERNEL_SECURITY_TOKEN)) == 0) {
+                   &KERNEL_SECURITY_TOKEN,
+                   sizeof(KERNEL_SECURITY_TOKEN)) == 0) {
                        send_pid = 0;
                        msg_flags &= ~(KMSG_TRACE_FLAG_APP_SRC | KMSG_TRACE_FLAG_DAEMON_SRC);
                }
        }
 
-       KDBG(MACHDBG_CODE(DBG_MACH_IPC,MACH_IPC_KMSG_INFO) | DBG_FUNC_END,
-                (uintptr_t)send_pid,
-                (uintptr_t)dst_pid,
-                (uintptr_t)msg_size,
-                (uintptr_t)(
-                  ((msg_flags & KMSG_TRACE_FLAGS_MASK) << KMSG_TRACE_FLAGS_SHIFT) |
-                  ((num_ports & KMSG_TRACE_PORTS_MASK) << KMSG_TRACE_PORTS_SHIFT)
-                )
-       );
+       KDBG(MACHDBG_CODE(DBG_MACH_IPC, MACH_IPC_KMSG_INFO) | DBG_FUNC_END,
+           (uintptr_t)send_pid,
+           (uintptr_t)dst_pid,
+           (uintptr_t)msg_size,
+           (uintptr_t)(
+                   ((msg_flags & KMSG_TRACE_FLAGS_MASK) << KMSG_TRACE_FLAGS_SHIFT) |
+                   ((num_ports & KMSG_TRACE_PORTS_MASK) << KMSG_TRACE_PORTS_SHIFT)
+                   )
+           );
 }
 #endif
 
 /* zone for cached ipc_kmsg_t structures */
-zone_t                 ipc_kmsg_zone;
+zone_t                  ipc_kmsg_zone;
 
 /*
  * Forward declarations
  */
 
 void ipc_kmsg_clean(
-       ipc_kmsg_t      kmsg);
+       ipc_kmsg_t      kmsg);
 
 void ipc_kmsg_clean_body(
-       ipc_kmsg_t      kmsg,
-       mach_msg_type_number_t  number,
-       mach_msg_descriptor_t   *desc);
+       ipc_kmsg_t      kmsg,
+       mach_msg_type_number_t  number,
+       mach_msg_descriptor_t   *desc);
 
 void ipc_kmsg_clean_partial(
-       ipc_kmsg_t              kmsg,
-       mach_msg_type_number_t  number,
-       mach_msg_descriptor_t   *desc,
-       vm_offset_t             paddr,
-       vm_size_t               length);
+       ipc_kmsg_t              kmsg,
+       mach_msg_type_number_t  number,
+       mach_msg_descriptor_t   *desc,
+       vm_offset_t             paddr,
+       vm_size_t               length);
 
 mach_msg_return_t ipc_kmsg_copyin_body(
-       ipc_kmsg_t              kmsg,
-       ipc_space_t             space,
-       vm_map_t                map);
+       ipc_kmsg_t          kmsg,
+       ipc_space_t         space,
+       vm_map_t            map,
+       mach_msg_option_t   *optionp);
+
+
+extern int enforce_strict_reply;
+
+static void
+ipc_kmsg_link_reply_context_locked(
+       ipc_port_t reply_port,
+       ipc_port_t voucher_port);
 
-extern int thread_qos_from_pthread_priority(unsigned long, unsigned long *);
+static kern_return_t
+ipc_kmsg_validate_reply_port_locked(
+       ipc_port_t reply_port,
+       mach_msg_option_t options);
+
+static mach_msg_return_t
+ipc_kmsg_validate_reply_context_locked(
+       mach_msg_option_t option,
+       ipc_port_t dest_port,
+       ipc_voucher_t voucher,
+       mach_port_name_t voucher_name);
+
+/* we can't include the BSD <sys/persona.h> header here... */
+#ifndef PERSONA_ID_NONE
+#define PERSONA_ID_NONE ((uint32_t)-1)
+#endif
 
 /*
  *     We keep a per-processor cache of kernel message buffers.
@@ -881,7 +940,7 @@ ipc_kmsg_alloc(
        /*
         * LP64support -
         * Pad the allocation in case we need to expand the
-        * message descrptors for user spaces with pointers larger than
+        * message descriptors for user spaces with pointers larger than
         * the kernel's own, or vice versa.  We don't know how many descriptors
         * there are yet, so just assume the whole body could be
         * descriptors (if there could be any at all).
@@ -894,41 +953,29 @@ ipc_kmsg_alloc(
        mach_msg_size_t size = msg_and_trailer_size - MAX_TRAILER_SIZE;
 
        /* compare against implementation upper limit for the body */
-       if (size > ipc_kmsg_max_body_space)
+       if (size > ipc_kmsg_max_body_space) {
                return IKM_NULL;
+       }
 
        if (size > sizeof(mach_msg_base_t)) {
                mach_msg_size_t max_desc = (mach_msg_size_t)(((size - sizeof(mach_msg_base_t)) /
-                                          sizeof(mach_msg_ool_descriptor32_t)) *
-                                          DESC_SIZE_ADJUSTMENT);
+                   sizeof(mach_msg_ool_descriptor32_t)) *
+                   DESC_SIZE_ADJUSTMENT);
 
                /* make sure expansion won't cause wrap */
-               if (msg_and_trailer_size > MACH_MSG_SIZE_MAX - max_desc)
+               if (msg_and_trailer_size > MACH_MSG_SIZE_MAX - max_desc) {
                        return IKM_NULL;
+               }
 
                max_expanded_size = msg_and_trailer_size + max_desc;
-       } else
-         max_expanded_size = msg_and_trailer_size;
-
-       if (max_expanded_size < IKM_SAVED_MSG_SIZE)
-               max_expanded_size = IKM_SAVED_MSG_SIZE;         /* round up for ikm_cache */
+       } else {
+               max_expanded_size = msg_and_trailer_size;
+       }
 
+       if (max_expanded_size < IKM_SAVED_MSG_SIZE) {
+               max_expanded_size = IKM_SAVED_MSG_SIZE;         /* round up for ikm_cache */
+       }
        if (max_expanded_size == IKM_SAVED_MSG_SIZE) {
-               struct ikm_cache        *cache;
-               unsigned int            i;
-
-               disable_preemption();
-               cache = &PROCESSOR_DATA(current_processor(), ikm_cache);
-               if ((i = cache->avail) > 0) {
-                       assert(i <= IKM_STASH);
-                       kmsg = cache->entries[--i];
-                       cache->avail = i;
-                       enable_preemption();
-                       ikm_check_init(kmsg, max_expanded_size);
-                       ikm_set_header(kmsg, msg_and_trailer_size);
-                       return (kmsg);
-               }
-               enable_preemption();
                kmsg = (ipc_kmsg_t)zalloc(ipc_kmsg_zone);
        } else {
                kmsg = (ipc_kmsg_t)kalloc(ikm_plus_overhead(max_expanded_size));
@@ -939,7 +986,7 @@ ipc_kmsg_alloc(
                ikm_set_header(kmsg, msg_and_trailer_size);
        }
 
-       return(kmsg);
+       return kmsg;
 }
 
 /*
@@ -956,16 +1003,16 @@ ipc_kmsg_alloc(
 
 void
 ipc_kmsg_free(
-       ipc_kmsg_t      kmsg)
+       ipc_kmsg_t      kmsg)
 {
        mach_msg_size_t size = kmsg->ikm_size;
        ipc_port_t port;
 
        assert(!IP_VALID(kmsg->ikm_voucher));
 
-       KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_IPC,MACH_IPC_KMSG_FREE) | DBG_FUNC_NONE,
-                             VM_KERNEL_ADDRPERM((uintptr_t)kmsg),
-                             0, 0, 0, 0);
+       KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_IPC, MACH_IPC_KMSG_FREE) | DBG_FUNC_NONE,
+           VM_KERNEL_ADDRPERM((uintptr_t)kmsg),
+           0, 0, 0, 0);
 
        /*
         * Check to see if the message is bound to the port.  If so,
@@ -982,26 +1029,11 @@ ipc_kmsg_free(
                        ip_release(port);
                        return;
                }
-                ip_unlock(port);
+               ip_unlock(port);
                ip_release(port); /* May be last reference */
        }
 
-       /*
-        * Peek and see if it has to go back in the cache.
-        */
        if (kmsg->ikm_size == IKM_SAVED_MSG_SIZE) {
-               struct ikm_cache        *cache;
-               unsigned int            i;
-
-               disable_preemption();
-               cache = &PROCESSOR_DATA(current_processor(), ikm_cache);
-               if ((i = cache->avail) < IKM_STASH) {
-                       cache->entries[i] = kmsg;
-                       cache->avail = i + 1;
-                       enable_preemption();
-                       return;
-               }
-               enable_preemption();
                zfree(ipc_kmsg_zone, kmsg);
                return;
        }
@@ -1017,8 +1049,8 @@ ipc_kmsg_free(
 
 void
 ipc_kmsg_enqueue(
-       ipc_kmsg_queue_t        queue,
-       ipc_kmsg_t              kmsg)
+       ipc_kmsg_queue_t        queue,
+       ipc_kmsg_t              kmsg)
 {
        ipc_kmsg_t first = queue->ikmq_base;
        ipc_kmsg_t last;
@@ -1050,8 +1082,8 @@ ipc_kmsg_enqueue(
 
 boolean_t
 ipc_kmsg_enqueue_qos(
-       ipc_kmsg_queue_t        queue,
-       ipc_kmsg_t              kmsg)
+       ipc_kmsg_queue_t        queue,
+       ipc_kmsg_t              kmsg)
 {
        ipc_kmsg_t first = queue->ikmq_base;
        ipc_kmsg_t prev;
@@ -1075,13 +1107,13 @@ ipc_kmsg_enqueue_qos(
        /* apply QoS overrides towards the head */
        override = kmsg->ikm_qos_override;
        while (prev != kmsg &&
-              override > prev->ikm_qos_override) {
+           override > prev->ikm_qos_override) {
                prev->ikm_qos_override = override;
                prev = prev->ikm_prev;
        }
 
        /* did we adjust everything? */
-       return (prev == kmsg);
+       return prev == kmsg;
 }
 
 /*
@@ -1099,7 +1131,7 @@ ipc_kmsg_enqueue_qos(
 
 boolean_t
 ipc_kmsg_override_qos(
-       ipc_kmsg_queue_t        queue,
+       ipc_kmsg_queue_t        queue,
        ipc_kmsg_t          kmsg,
        mach_msg_priority_t override)
 {
@@ -1109,9 +1141,10 @@ ipc_kmsg_override_qos(
        /* apply QoS overrides towards the head */
        while (override > cur->ikm_qos_override) {
                cur->ikm_qos_override = override;
-               if (cur == first)
+               if (cur == first) {
                        return TRUE;
-                cur = cur->ikm_prev;
+               }
+               cur = cur->ikm_prev;
        }
        return FALSE;
 }
@@ -1124,14 +1157,15 @@ ipc_kmsg_override_qos(
 
 ipc_kmsg_t
 ipc_kmsg_dequeue(
-       ipc_kmsg_queue_t        queue)
+       ipc_kmsg_queue_t        queue)
 {
        ipc_kmsg_t first;
 
        first = ipc_kmsg_queue_first(queue);
 
-       if (first != IKM_NULL)
+       if (first != IKM_NULL) {
                ipc_kmsg_rmqueue(queue, first);
+       }
 
        return first;
 }
@@ -1144,8 +1178,8 @@ ipc_kmsg_dequeue(
 
 void
 ipc_kmsg_rmqueue(
-       ipc_kmsg_queue_t        queue,
-       ipc_kmsg_t              kmsg)
+       ipc_kmsg_queue_t        queue,
+       ipc_kmsg_t              kmsg)
 {
        ipc_kmsg_t next, prev;
 
@@ -1160,8 +1194,15 @@ ipc_kmsg_rmqueue(
 
                queue->ikmq_base = IKM_NULL;
        } else {
-               if (queue->ikmq_base == kmsg)
+               if (__improbable(next->ikm_prev != kmsg || prev->ikm_next != kmsg)) {
+                       panic("ipc_kmsg_rmqueue: inconsistent prev/next pointers. "
+                           "(prev->next: %p, next->prev: %p, kmsg: %p)",
+                           prev->ikm_next, next->ikm_prev, kmsg);
+               }
+
+               if (queue->ikmq_base == kmsg) {
                        queue->ikmq_base = next;
+               }
 
                next->ikm_prev = prev;
                prev->ikm_next = next;
@@ -1180,16 +1221,17 @@ ipc_kmsg_rmqueue(
 
 ipc_kmsg_t
 ipc_kmsg_queue_next(
-       ipc_kmsg_queue_t        queue,
-       ipc_kmsg_t              kmsg)
+       ipc_kmsg_queue_t        queue,
+       ipc_kmsg_t              kmsg)
 {
        ipc_kmsg_t next;
 
        assert(queue->ikmq_base != IKM_NULL);
 
        next = kmsg->ikm_next;
-       if (queue->ikmq_base == next)
+       if (queue->ikmq_base == next) {
                next = IKM_NULL;
+       }
 
        return next;
 }
@@ -1206,7 +1248,7 @@ ipc_kmsg_queue_next(
 
 void
 ipc_kmsg_destroy(
-       ipc_kmsg_t      kmsg)
+       ipc_kmsg_t      kmsg)
 {
        /*
         *      Destroying a message can cause more messages to be destroyed.
@@ -1214,8 +1256,9 @@ ipc_kmsg_destroy(
         *      destruction queue.  If this was the first message on the
         *      queue, this instance must process the full queue.
         */
-       if (ipc_kmsg_delayed_destroy(kmsg))
+       if (ipc_kmsg_delayed_destroy(kmsg)) {
                ipc_kmsg_reap_delayed();
+       }
 }
 
 /*
@@ -1227,7 +1270,8 @@ ipc_kmsg_destroy(
  *             deferred messages.
  */
 
-boolean_t ipc_kmsg_delayed_destroy(
+boolean_t
+ipc_kmsg_delayed_destroy(
        ipc_kmsg_t kmsg)
 {
        ipc_kmsg_queue_t queue = &(current_thread()->ith_messages);
@@ -1275,86 +1319,99 @@ ipc_kmsg_reap_delayed(void)
 static unsigned int _ipc_kmsg_clean_invalid_desc = 0;
 void
 ipc_kmsg_clean_body(
-       __unused ipc_kmsg_t     kmsg,
-       mach_msg_type_number_t  number,
-       mach_msg_descriptor_t   *saddr)
+       __unused ipc_kmsg_t     kmsg,
+       mach_msg_type_number_t  number,
+       mach_msg_descriptor_t   *saddr)
 {
-    mach_msg_type_number_t     i;
+       mach_msg_type_number_t      i;
 
-    if ( number == 0 )
-       return;
+       if (number == 0) {
+               return;
+       }
 
-    for (i = 0 ; i < number; i++, saddr++ ) {
-       
-       switch (saddr->type.type) {
-           
-           case MACH_MSG_PORT_DESCRIPTOR: {
-               mach_msg_port_descriptor_t *dsc;
+       for (i = 0; i < number; i++, saddr++) {
+               switch (saddr->type.type) {
+               case MACH_MSG_PORT_DESCRIPTOR: {
+                       mach_msg_port_descriptor_t *dsc;
 
-               dsc = &saddr->port;
+                       dsc = &saddr->port;
 
-               /* 
-                * Destroy port rights carried in the message 
-                */
-               if (!IO_VALID((ipc_object_t) dsc->name))
-                   continue;
-               ipc_object_destroy((ipc_object_t) dsc->name, dsc->disposition);
-               break;
-           }
-           case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
-           case MACH_MSG_OOL_DESCRIPTOR : {
-               mach_msg_ool_descriptor_t *dsc;
-
-               dsc = (mach_msg_ool_descriptor_t *)&saddr->out_of_line;
-               
-               /* 
-                * Destroy memory carried in the message 
-                */
-               if (dsc->size == 0) {
-                       assert(dsc->address == (void *) 0);
-               } else {
-                       vm_map_copy_discard((vm_map_copy_t) dsc->address);
+                       /*
+                        * Destroy port rights carried in the message
+                        */
+                       if (!IP_VALID(dsc->name)) {
+                               continue;
+                       }
+                       ipc_object_destroy(ip_to_object(dsc->name), dsc->disposition);
+                       break;
                }
-               break;
-           }
-           case MACH_MSG_OOL_PORTS_DESCRIPTOR : {
-               ipc_object_t                    *objects;
-               mach_msg_type_number_t          j;
-               mach_msg_ool_ports_descriptor_t *dsc;
+               case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
+               case MACH_MSG_OOL_DESCRIPTOR: {
+                       mach_msg_ool_descriptor_t *dsc;
 
-               dsc = (mach_msg_ool_ports_descriptor_t  *)&saddr->ool_ports;
-               objects = (ipc_object_t *) dsc->address;
+                       dsc = (mach_msg_ool_descriptor_t *)&saddr->out_of_line;
 
-               if (dsc->count == 0) {
+                       /*
+                        * Destroy memory carried in the message
+                        */
+                       if (dsc->size == 0) {
+                               assert(dsc->address == (void *) 0);
+                       } else {
+                               vm_map_copy_discard((vm_map_copy_t) dsc->address);
+                       }
                        break;
                }
+               case MACH_MSG_OOL_PORTS_DESCRIPTOR: {
+                       ipc_object_t                    *objects;
+                       mach_msg_type_number_t          j;
+                       mach_msg_ool_ports_descriptor_t *dsc;
 
-               assert(objects != (ipc_object_t *) 0);
-               
-               /* destroy port rights carried in the message */
-               
-               for (j = 0; j < dsc->count; j++) {
-                   ipc_object_t object = objects[j];
-                   
-                   if (!IO_VALID(object))
-                       continue;
-                   
-                   ipc_object_destroy(object, dsc->disposition);
-               }
+                       dsc = (mach_msg_ool_ports_descriptor_t  *)&saddr->ool_ports;
+                       objects = (ipc_object_t *) dsc->address;
+
+                       if (dsc->count == 0) {
+                               break;
+                       }
 
-               /* destroy memory carried in the message */
+                       assert(objects != (ipc_object_t *) 0);
 
-               assert(dsc->count != 0);
+                       /* destroy port rights carried in the message */
 
-               kfree(dsc->address, 
-                    (vm_size_t) dsc->count * sizeof(mach_port_t));
-               break;
-           }
-           default : {
-                   _ipc_kmsg_clean_invalid_desc++; /* don't understand this type of descriptor */
-           }
+                       for (j = 0; j < dsc->count; j++) {
+                               ipc_object_t object = objects[j];
+
+                               if (!IO_VALID(object)) {
+                                       continue;
+                               }
+
+                               ipc_object_destroy(object, dsc->disposition);
+                       }
+
+                       /* destroy memory carried in the message */
+
+                       assert(dsc->count != 0);
+
+                       kfree(dsc->address,
+                           (vm_size_t) dsc->count * sizeof(mach_port_t));
+                       break;
+               }
+               case MACH_MSG_GUARDED_PORT_DESCRIPTOR: {
+                       mach_msg_guarded_port_descriptor_t *dsc = (typeof(dsc)) & saddr->guarded_port;
+
+                       /*
+                        * Destroy port rights carried in the message
+                        */
+                       if (!IP_VALID(dsc->name)) {
+                               continue;
+                       }
+                       ipc_object_destroy(ip_to_object(dsc->name), dsc->disposition);
+                       break;
+               }
+               default: {
+                       _ipc_kmsg_clean_invalid_desc++;         /* don't understand this type of descriptor */
+               }
+               }
        }
-    }
 }
 
 /*
@@ -1372,11 +1429,11 @@ ipc_kmsg_clean_body(
 
 void
 ipc_kmsg_clean_partial(
-       ipc_kmsg_t              kmsg,
-       mach_msg_type_number_t  number,
-       mach_msg_descriptor_t   *desc,
-       vm_offset_t             paddr,
-       vm_size_t               length)
+       ipc_kmsg_t              kmsg,
+       mach_msg_type_number_t  number,
+       mach_msg_descriptor_t   *desc,
+       vm_offset_t             paddr,
+       vm_size_t               length)
 {
        ipc_object_t object;
        mach_msg_bits_t mbits = kmsg->ikm_header->msgh_bits;
@@ -1384,15 +1441,16 @@ ipc_kmsg_clean_partial(
        /* deal with importance chain while we still have dest and voucher references */
        ipc_importance_clean(kmsg);
 
-       object = (ipc_object_t) kmsg->ikm_header->msgh_remote_port;
+       object = ip_to_object(kmsg->ikm_header->msgh_remote_port);
        assert(IO_VALID(object));
        ipc_object_destroy_dest(object, MACH_MSGH_BITS_REMOTE(mbits));
 
-       object = (ipc_object_t) kmsg->ikm_header->msgh_local_port;
-       if (IO_VALID(object))
+       object = ip_to_object(kmsg->ikm_header->msgh_local_port);
+       if (IO_VALID(object)) {
                ipc_object_destroy(object, MACH_MSGH_BITS_LOCAL(mbits));
+       }
 
-       object = (ipc_object_t) kmsg->ikm_voucher;
+       object = ip_to_object(kmsg->ikm_voucher);
        if (IO_VALID(object)) {
                assert(MACH_MSGH_BITS_VOUCHER(mbits) == MACH_MSG_TYPE_MOVE_SEND);
                ipc_object_destroy(object, MACH_MSG_TYPE_PORT_SEND);
@@ -1417,7 +1475,7 @@ ipc_kmsg_clean_partial(
 
 void
 ipc_kmsg_clean(
-       ipc_kmsg_t      kmsg)
+       ipc_kmsg_t      kmsg)
 {
        ipc_object_t object;
        mach_msg_bits_t mbits;
@@ -1426,15 +1484,17 @@ ipc_kmsg_clean(
        ipc_importance_clean(kmsg);
 
        mbits = kmsg->ikm_header->msgh_bits;
-       object = (ipc_object_t) kmsg->ikm_header->msgh_remote_port;
-       if (IO_VALID(object))
+       object = ip_to_object(kmsg->ikm_header->msgh_remote_port);
+       if (IO_VALID(object)) {
                ipc_object_destroy_dest(object, MACH_MSGH_BITS_REMOTE(mbits));
+       }
 
-       object = (ipc_object_t) kmsg->ikm_header->msgh_local_port;
-       if (IO_VALID(object))
+       object = ip_to_object(kmsg->ikm_header->msgh_local_port);
+       if (IO_VALID(object)) {
                ipc_object_destroy(object, MACH_MSGH_BITS_LOCAL(mbits));
+       }
 
-       object = (ipc_object_t) kmsg->ikm_voucher;
+       object = ip_to_object(kmsg->ikm_voucher);
        if (IO_VALID(object)) {
                assert(MACH_MSGH_BITS_VOUCHER(mbits) == MACH_MSG_TYPE_MOVE_SEND);
                ipc_object_destroy(object, MACH_MSG_TYPE_PORT_SEND);
@@ -1446,7 +1506,7 @@ ipc_kmsg_clean(
 
                body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
                ipc_kmsg_clean_body(kmsg, body->msgh_descriptor_count,
-                                   (mach_msg_descriptor_t *)(body + 1));
+                   (mach_msg_descriptor_t *)(body + 1));
        }
 }
 
@@ -1460,22 +1520,16 @@ ipc_kmsg_clean(
 
 void
 ipc_kmsg_set_prealloc(
-       ipc_kmsg_t              kmsg,
-       ipc_port_t              port)
+       ipc_kmsg_t              kmsg,
+       ipc_port_t              port)
 {
        assert(kmsg->ikm_prealloc == IP_NULL);
-  
+
        kmsg->ikm_prealloc = IP_NULL;
-       /* take the mqueue lock since the sync qos is protected under it */
-       imq_lock(&port->ip_messages);
 
-       /* copy the sync qos values to kmsg */
-       for (int i = 0; i < THREAD_QOS_LAST; i++) {
-               kmsg->sync_qos[i] = port_sync_qos(port, i);
-       }
-       kmsg->special_port_qos = port_special_qos(port);
+       assert(port_send_turnstile(port) == TURNSTILE_NULL);
+       kmsg->ikm_turnstile = TURNSTILE_NULL;
        IP_SET_PREALLOC(port, kmsg);
-       imq_unlock(&port->ip_messages);
 }
 
 /*
@@ -1487,23 +1541,14 @@ ipc_kmsg_set_prealloc(
  */
 void
 ipc_kmsg_clear_prealloc(
-       ipc_kmsg_t              kmsg,
-       ipc_port_t              port)
+       ipc_kmsg_t              kmsg,
+       ipc_port_t              port)
 {
-       assert(kmsg->ikm_prealloc == port);
-  
-       kmsg->ikm_prealloc = IP_NULL;
-
-       /* take the mqueue lock since the sync qos is protected under it */
+       /* take the mqueue lock since the turnstile is protected under it */
        imq_lock(&port->ip_messages);
 
        IP_CLEAR_PREALLOC(port, kmsg);
-
-       /* copy the sync qos values from kmsg to port */
-       for (int i = 0; i < THREAD_QOS_LAST; i++) {
-               set_port_sync_qos(port, i, kmsg->sync_qos[i]);
-       }
-       set_port_special_qos(port, kmsg->special_port_qos);
+       set_port_send_turnstile(port, kmsg->ikm_turnstile);
        imq_unlock(&port->ip_messages);
 }
 
@@ -1517,8 +1562,9 @@ ipc_kmsg_t
 ipc_kmsg_prealloc(mach_msg_size_t size)
 {
 #if defined(__LP64__)
-       if (size > MACH_MSG_SIZE_MAX - LEGACY_HEADER_SIZE_DELTA)
+       if (size > MACH_MSG_SIZE_MAX - LEGACY_HEADER_SIZE_DELTA) {
                return IKM_NULL;
+       }
 
        size += LEGACY_HEADER_SIZE_DELTA;
 #endif
@@ -1544,38 +1590,43 @@ ipc_kmsg_prealloc(mach_msg_size_t size)
 
 mach_msg_return_t
 ipc_kmsg_get(
-       mach_vm_address_t       msg_addr,
-       mach_msg_size_t size,
-       ipc_kmsg_t              *kmsgp)
+       mach_vm_address_t       msg_addr,
+       mach_msg_size_t size,
+       ipc_kmsg_t              *kmsgp)
 {
-       mach_msg_size_t                 msg_and_trailer_size;
-       ipc_kmsg_t                      kmsg;
-       mach_msg_max_trailer_t          *trailer;
-       mach_msg_legacy_base_t      legacy_base;
+       mach_msg_size_t                 msg_and_trailer_size;
+       ipc_kmsg_t                      kmsg;
+       mach_msg_max_trailer_t          *trailer;
+       mach_msg_legacy_base_t      legacy_base;
        mach_msg_size_t             len_copied;
        legacy_base.body.msgh_descriptor_count = 0;
 
-       if ((size < sizeof(mach_msg_legacy_header_t)) || (size & 3))
+       if ((size < sizeof(mach_msg_legacy_header_t)) || (size & 3)) {
                return MACH_SEND_MSG_TOO_SMALL;
+       }
 
-       if (size > ipc_kmsg_max_body_space)
+       if (size > ipc_kmsg_max_body_space) {
                return MACH_SEND_TOO_LARGE;
+       }
 
-       if(size == sizeof(mach_msg_legacy_header_t))
+       if (size == sizeof(mach_msg_legacy_header_t)) {
                len_copied = sizeof(mach_msg_legacy_header_t);
-       else
+       } else {
                len_copied = sizeof(mach_msg_legacy_base_t);
+       }
 
-       if (copyinmsg(msg_addr, (char *)&legacy_base, len_copied))
+       if (copyinmsg(msg_addr, (char *)&legacy_base, len_copied)) {
                return MACH_SEND_INVALID_DATA;
+       }
 
        /*
         * If the message claims to be complex, it must at least
         * have the length of a "base" message (header + dsc_count).
         */
        if (len_copied < sizeof(mach_msg_legacy_base_t) &&
-           (legacy_base.header.msgh_bits & MACH_MSGH_BITS_COMPLEX))
+           (legacy_base.header.msgh_bits & MACH_MSGH_BITS_COMPLEX)) {
                return MACH_SEND_MSG_TOO_SMALL;
+       }
 
        msg_addr += sizeof(legacy_base.header);
 #if defined(__LP64__)
@@ -1585,37 +1636,38 @@ ipc_kmsg_get(
        __unreachable_ok_push
        if (DEBUG_KPRINT_SYSCALL_PREDICATE(DEBUG_KPRINT_SYSCALL_IPC_MASK)) {
                unsigned int j;
-               for (j=0; j<sizeof(legacy_base.header); j++) {
+               for (j = 0; j < sizeof(legacy_base.header); j++) {
                        kprintf("%02x\n", ((unsigned char*)&legacy_base.header)[j]);
                }
        }
        __unreachable_ok_pop
 
-       msg_and_trailer_size = size + MAX_TRAILER_SIZE;
+           msg_and_trailer_size = size + MAX_TRAILER_SIZE;
        kmsg = ipc_kmsg_alloc(msg_and_trailer_size);
-       if (kmsg == IKM_NULL)
+       if (kmsg == IKM_NULL) {
                return MACH_SEND_NO_BUFFER;
+       }
 
-       kmsg->ikm_header->msgh_size                     = size;
-       kmsg->ikm_header->msgh_bits                     = legacy_base.header.msgh_bits;
-       kmsg->ikm_header->msgh_remote_port      = CAST_MACH_NAME_TO_PORT(legacy_base.header.msgh_remote_port);
-       kmsg->ikm_header->msgh_local_port       = CAST_MACH_NAME_TO_PORT(legacy_base.header.msgh_local_port);
-       kmsg->ikm_header->msgh_voucher_port             = legacy_base.header.msgh_voucher_port;
-       kmsg->ikm_header->msgh_id                       = legacy_base.header.msgh_id;
+       kmsg->ikm_header->msgh_size                     = size;
+       kmsg->ikm_header->msgh_bits                     = legacy_base.header.msgh_bits;
+       kmsg->ikm_header->msgh_remote_port      = CAST_MACH_NAME_TO_PORT(legacy_base.header.msgh_remote_port);
+       kmsg->ikm_header->msgh_local_port       = CAST_MACH_NAME_TO_PORT(legacy_base.header.msgh_local_port);
+       kmsg->ikm_header->msgh_voucher_port             = legacy_base.header.msgh_voucher_port;
+       kmsg->ikm_header->msgh_id                       = legacy_base.header.msgh_id;
 
        DEBUG_KPRINT_SYSCALL_IPC("ipc_kmsg_get header:\n"
-                                                        "  size:               0x%.8x\n"
-                                                        "  bits:               0x%.8x\n"
-                                                        "  remote_port:        %p\n"
-                                                        "  local_port: %p\n"
-                                                        "  voucher_port:       0x%.8x\n"
-                                                        "  id:         %.8d\n",
-                                                        kmsg->ikm_header->msgh_size,
-                                                        kmsg->ikm_header->msgh_bits,
-                                                        kmsg->ikm_header->msgh_remote_port,
-                                                        kmsg->ikm_header->msgh_local_port,
-                                                        kmsg->ikm_header->msgh_voucher_port,
-                                                        kmsg->ikm_header->msgh_id);
+           "  size:            0x%.8x\n"
+           "  bits:            0x%.8x\n"
+           "  remote_port:     %p\n"
+           "  local_port:      %p\n"
+           "  voucher_port:    0x%.8x\n"
+           "  id:              %.8d\n",
+           kmsg->ikm_header->msgh_size,
+           kmsg->ikm_header->msgh_bits,
+           kmsg->ikm_header->msgh_remote_port,
+           kmsg->ikm_header->msgh_local_port,
+           kmsg->ikm_header->msgh_voucher_port,
+           kmsg->ikm_header->msgh_id);
 
        if (copyinmsg(msg_addr, (char *)(kmsg->ikm_header + 1), size - (mach_msg_size_t)sizeof(mach_msg_header_t))) {
                ipc_kmsg_free(kmsg);
@@ -1624,19 +1676,17 @@ ipc_kmsg_get(
 
        /* unreachable if !DEBUG */
        __unreachable_ok_push
-       if (DEBUG_KPRINT_SYSCALL_PREDICATE(DEBUG_KPRINT_SYSCALL_IPC_MASK))
-       {
+       if (DEBUG_KPRINT_SYSCALL_PREDICATE(DEBUG_KPRINT_SYSCALL_IPC_MASK)) {
                kprintf("body: size: %lu\n", (size - sizeof(mach_msg_header_t)));
                uint32_t i;
-               for(i=0;i*4 < (size - sizeof(mach_msg_header_t));i++)
-               {
-                       kprintf("%.4x\n",((uint32_t *)(kmsg->ikm_header + 1))[i]);
+               for (i = 0; i * 4 < (size - sizeof(mach_msg_header_t)); i++) {
+                       kprintf("%.4x\n", ((uint32_t *)(kmsg->ikm_header + 1))[i]);
                }
        }
        __unreachable_ok_pop
        DEBUG_IPC_KMSG_PRINT(kmsg, "ipc_kmsg_get()");
 
-       /* 
+       /*
         * I reserve for the trailer the largest space (MAX_TRAILER_SIZE)
         * However, the internal size field of the trailer (msgh_trailer_size)
         * is initialized to the minimum (sizeof(mach_msg_trailer_t)), to optimize
@@ -1649,9 +1699,11 @@ ipc_kmsg_get(
        trailer->msgh_trailer_size = MACH_MSG_TRAILER_MINIMUM_SIZE;
 
 #ifdef ppc
-       if(trcWork.traceMask) dbgTrace(0x1100, (unsigned int)kmsg->ikm_header->msgh_id, 
-               (unsigned int)kmsg->ikm_header->msgh_remote_port, 
-               (unsigned int)kmsg->ikm_header->msgh_local_port, 0); 
+       if (trcWork.traceMask) {
+               dbgTrace(0x1100, (unsigned int)kmsg->ikm_header->msgh_id,
+                   (unsigned int)kmsg->ikm_header->msgh_remote_port,
+                   (unsigned int)kmsg->ikm_header->msgh_local_port, 0);
+       }
 #endif
 
        trailer->msgh_labels.sender = 0;
@@ -1677,19 +1729,19 @@ ipc_kmsg_get(
 
 mach_msg_return_t
 ipc_kmsg_get_from_kernel(
-       mach_msg_header_t       *msg,
-       mach_msg_size_t size,
-       ipc_kmsg_t              *kmsgp)
+       mach_msg_header_t       *msg,
+       mach_msg_size_t size,
+       ipc_kmsg_t              *kmsgp)
 {
-       ipc_kmsg_t      kmsg;
-       mach_msg_size_t msg_and_trailer_size;
+       ipc_kmsg_t      kmsg;
+       mach_msg_size_t msg_and_trailer_size;
        mach_msg_max_trailer_t *trailer;
-       ipc_port_t      dest_port;
+       ipc_port_t      dest_port;
 
        assert(size >= sizeof(mach_msg_header_t));
        assert((size & 3) == 0);
 
-       dest_port = (ipc_port_t)msg->msgh_remote_port;
+       dest_port = msg->msgh_remote_port;
 
        msg_and_trailer_size = size + MAX_TRAILER_SIZE;
 
@@ -1716,7 +1768,7 @@ ipc_kmsg_get_from_kernel(
                if (msg->msgh_bits & MACH_MSGH_BITS_COMPLEX) {
                        assert(size > sizeof(mach_msg_base_t));
                        max_desc = ((mach_msg_base_t *)msg)->body.msgh_descriptor_count *
-                               DESC_SIZE_ADJUSTMENT;
+                           DESC_SIZE_ADJUSTMENT;
                }
 #endif
                if (msg_and_trailer_size > kmsg->ikm_size - max_desc) {
@@ -1726,12 +1778,11 @@ ipc_kmsg_get_from_kernel(
                ikm_prealloc_set_inuse(kmsg, dest_port);
                ikm_set_header(kmsg, msg_and_trailer_size);
                ip_unlock(dest_port);
-       }
-       else
-       {
+       } else {
                kmsg = ipc_kmsg_alloc(msg_and_trailer_size);
-               if (kmsg == IKM_NULL)
+               if (kmsg == IKM_NULL) {
                        return MACH_SEND_NO_BUFFER;
+               }
        }
 
        (void) memcpy((void *) kmsg->ikm_header, (const void *) msg, size);
@@ -1740,14 +1791,14 @@ ipc_kmsg_get_from_kernel(
 
        kmsg->ikm_header->msgh_size = size;
 
-       /* 
+       /*
         * I reserve for the trailer the largest space (MAX_TRAILER_SIZE)
         * However, the internal size field of the trailer (msgh_trailer_size)
         * is initialized to the minimum (sizeof(mach_msg_trailer_t)), to
         * optimize the cases where no implicit data is requested.
         */
-       trailer = (mach_msg_max_trailer_t *) 
-                 ((vm_offset_t)kmsg->ikm_header + size);
+       trailer = (mach_msg_max_trailer_t *)
+           ((vm_offset_t)kmsg->ikm_header + size);
        trailer->msgh_sender = KERNEL_SECURITY_TOKEN;
        trailer->msgh_audit = KERNEL_AUDIT_TOKEN;
        trailer->msgh_trailer_type = MACH_MSG_TRAILER_FORMAT_0;
@@ -1777,13 +1828,11 @@ ipc_kmsg_get_from_kernel(
  *             MACH_SEND_INTERRUPTED   Caller still has message.
  *             MACH_SEND_INVALID_DEST  Caller still has message.
  */
-
-
 mach_msg_return_t
 ipc_kmsg_send(
-       ipc_kmsg_t              kmsg,
-       mach_msg_option_t       option,
-       mach_msg_timeout_t      send_timeout)
+       ipc_kmsg_t              kmsg,
+       mach_msg_option_t       option,
+       mach_msg_timeout_t      send_timeout)
 {
        ipc_port_t port;
        thread_t th = current_thread();
@@ -1800,7 +1849,7 @@ ipc_kmsg_send(
        }
 
 #if IMPORTANCE_INHERITANCE
-       boolean_t did_importance = FALSE;
+       bool did_importance = false;
 #if IMPORTANCE_TRACE
        mach_msg_id_t imp_msgh_id = -1;
        int           sender_pid  = -1;
@@ -1810,16 +1859,32 @@ ipc_kmsg_send(
        /* don't allow the creation of a circular loop */
        if (kmsg->ikm_header->msgh_bits & MACH_MSGH_BITS_CIRCULAR) {
                ipc_kmsg_destroy(kmsg);
-               KDBG(MACHDBG_CODE(DBG_MACH_IPC,MACH_IPC_KMSG_INFO) | DBG_FUNC_END, MACH_MSGH_BITS_CIRCULAR);
+               KDBG(MACHDBG_CODE(DBG_MACH_IPC, MACH_IPC_KMSG_INFO) | DBG_FUNC_END, MACH_MSGH_BITS_CIRCULAR);
                return MACH_MSG_SUCCESS;
        }
 
        ipc_voucher_send_preprocessing(kmsg);
 
-       port = (ipc_port_t) kmsg->ikm_header->msgh_remote_port;
+       port = kmsg->ikm_header->msgh_remote_port;
        assert(IP_VALID(port));
        ip_lock(port);
 
+       /*
+        * If the destination has been guarded with a reply context, and the
+        * sender is consuming a send-once right, then assume this is a reply
+        * to an RPC and we need to validate that this sender is currently in
+        * the correct context.
+        */
+       if (enforce_strict_reply && port->ip_reply_context != 0 &&
+           ((option & MACH_SEND_KERNEL) == 0) &&
+           MACH_MSGH_BITS_REMOTE(kmsg->ikm_header->msgh_bits) == MACH_MSG_TYPE_PORT_SEND_ONCE) {
+               error = ipc_kmsg_validate_reply_context_locked(option, port, th->ith_voucher, th->ith_voucher_name);
+               if (error != MACH_MSG_SUCCESS) {
+                       ip_unlock(port);
+                       return error;
+               }
+       }
+
 #if IMPORTANCE_INHERITANCE
 retry:
 #endif /* IMPORTANCE_INHERITANCE */
@@ -1831,25 +1896,36 @@ retry:
        if (!ip_active(port)) {
                ip_unlock(port);
 #if MACH_FLIPC
-        if (MACH_NODE_VALID(kmsg->ikm_node) && FPORT_VALID(port->ip_messages.imq_fport))
-            flipc_msg_ack(kmsg->ikm_node, &port->ip_messages, FALSE);
+               if (MACH_NODE_VALID(kmsg->ikm_node) && FPORT_VALID(port->ip_messages.imq_fport)) {
+                       flipc_msg_ack(kmsg->ikm_node, &port->ip_messages, FALSE);
+               }
 #endif
+               if (did_importance) {
+                       /*
+                        * We're going to pretend we delivered this message
+                        * successfully, and just eat the kmsg. However, the
+                        * kmsg is actually visible via the importance_task!
+                        * We need to cleanup this linkage before we destroy
+                        * the message, and more importantly before we set the
+                        * msgh_remote_port to NULL. See: 34302571
+                        */
+                       ipc_importance_clean(kmsg);
+               }
                ip_release(port);  /* JMM - Future: release right, not just ref */
                kmsg->ikm_header->msgh_remote_port = MACH_PORT_NULL;
                ipc_kmsg_destroy(kmsg);
-               KDBG(MACHDBG_CODE(DBG_MACH_IPC,MACH_IPC_KMSG_INFO) | DBG_FUNC_END, MACH_SEND_INVALID_DEST);
+               KDBG(MACHDBG_CODE(DBG_MACH_IPC, MACH_IPC_KMSG_INFO) | DBG_FUNC_END, MACH_SEND_INVALID_DEST);
                return MACH_MSG_SUCCESS;
        }
 
        if (port->ip_receiver == ipc_space_kernel) {
-
                /*
                 *      We can check ip_receiver == ipc_space_kernel
                 *      before checking that the port is active because
                 *      ipc_port_dealloc_kernel clears ip_receiver
                 *      before destroying a kernel port.
                 */
-               assert(ip_active(port));
+               require_ip_active(port);
                port->ip_messages.imq_seqno++;
                ip_unlock(port);
 
@@ -1859,18 +1935,20 @@ retry:
                 * Call the server routine, and get the reply message to send.
                 */
                kmsg = ipc_kobject_server(kmsg, option);
-               if (kmsg == IKM_NULL)
+               if (kmsg == IKM_NULL) {
                        return MACH_MSG_SUCCESS;
+               }
 
                /* restart the KMSG_INFO tracing for the reply message */
-               KDBG(MACHDBG_CODE(DBG_MACH_IPC,MACH_IPC_KMSG_INFO) | DBG_FUNC_START);
-               port = (ipc_port_t) kmsg->ikm_header->msgh_remote_port;
+               KDBG(MACHDBG_CODE(DBG_MACH_IPC, MACH_IPC_KMSG_INFO) | DBG_FUNC_START);
+               port = kmsg->ikm_header->msgh_remote_port;
                assert(IP_VALID(port));
                ip_lock(port);
                /* fall thru with reply - same options */
                kernel_reply = TRUE;
-               if (!ip_active(port))
+               if (!ip_active(port)) {
                        error = MACH_SEND_INVALID_DEST;
+               }
        }
 
 #if IMPORTANCE_INHERITANCE
@@ -1879,10 +1957,11 @@ retry:
         * propagation.  That routine can drop the port lock temporarily.
         * If it does we'll have to revalidate the destination.
         */
-       if (did_importance == FALSE) {
-               did_importance = TRUE;
-               if (ipc_importance_send(kmsg, option))
-                       goto retry;
+       if (!did_importance) {
+               did_importance = true;
+               if (ipc_importance_send(kmsg, option)) {
+                       goto retry;
+               }
        }
 #endif /* IMPORTANCE_INHERITANCE */
 
@@ -1895,46 +1974,49 @@ retry:
                 * queue. Lock message queue while port is locked.
                 */
                imq_lock(&port->ip_messages);
+
+               ipc_special_reply_port_msg_sent(port);
+
                ip_unlock(port);
 
                error = ipc_mqueue_send(&port->ip_messages, kmsg, option,
-                               send_timeout);
+                   send_timeout);
        }
 
 #if IMPORTANCE_INHERITANCE
-       if (did_importance == TRUE) {
+       if (did_importance) {
                __unused int importance_cleared = 0;
                switch (error) {
-                       case MACH_SEND_TIMED_OUT:
-                       case MACH_SEND_NO_BUFFER:
-                       case MACH_SEND_INTERRUPTED:
-                       case MACH_SEND_INVALID_DEST:
-                               /*
-                                * We still have the kmsg and its
-                                * reference on the port.  But we
-                                * have to back out the importance
-                                * boost.
-                                *
-                                * The port could have changed hands,
-                                * be inflight to another destination,
-                                * etc...  But in those cases our
-                                * back-out will find the new owner
-                                * (and all the operations that
-                                * transferred the right should have
-                                * applied their own boost adjustments
-                                * to the old owner(s)).
-                                */
-                               importance_cleared = 1;
-                               ipc_importance_clean(kmsg);
-                               break;
+               case MACH_SEND_TIMED_OUT:
+               case MACH_SEND_NO_BUFFER:
+               case MACH_SEND_INTERRUPTED:
+               case MACH_SEND_INVALID_DEST:
+                       /*
+                        * We still have the kmsg and its
+                        * reference on the port.  But we
+                        * have to back out the importance
+                        * boost.
+                        *
+                        * The port could have changed hands,
+                        * be inflight to another destination,
+                        * etc...  But in those cases our
+                        * back-out will find the new owner
+                        * (and all the operations that
+                        * transferred the right should have
+                        * applied their own boost adjustments
+                        * to the old owner(s)).
+                        */
+                       importance_cleared = 1;
+                       ipc_importance_clean(kmsg);
+                       break;
 
-                       case MACH_MSG_SUCCESS:
-                       default:
-                               break;
+               case MACH_MSG_SUCCESS:
+               default:
+                       break;
                }
 #if IMPORTANCE_TRACE
                KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE, (IMPORTANCE_CODE(IMP_MSG, IMP_MSG_SEND)) | DBG_FUNC_END,
-                                         task_pid(current_task()), sender_pid, imp_msgh_id, importance_cleared, 0);
+                   task_pid(current_task()), sender_pid, imp_msgh_id, importance_cleared, 0);
 #endif /* IMPORTANCE_TRACE */
        }
 #endif /* IMPORTANCE_INHERITANCE */
@@ -1945,13 +2027,14 @@ retry:
         */
        if (error == MACH_SEND_INVALID_DEST) {
 #if MACH_FLIPC
-        if (MACH_NODE_VALID(kmsg->ikm_node) && FPORT_VALID(port->ip_messages.imq_fport))
-            flipc_msg_ack(kmsg->ikm_node, &port->ip_messages, FALSE);
+               if (MACH_NODE_VALID(kmsg->ikm_node) && FPORT_VALID(port->ip_messages.imq_fport)) {
+                       flipc_msg_ack(kmsg->ikm_node, &port->ip_messages, FALSE);
+               }
 #endif
                ip_release(port); /* JMM - Future: release right, not just ref */
                kmsg->ikm_header->msgh_remote_port = MACH_PORT_NULL;
                ipc_kmsg_destroy(kmsg);
-               KDBG(MACHDBG_CODE(DBG_MACH_IPC,MACH_IPC_KMSG_INFO) | DBG_FUNC_END, MACH_SEND_INVALID_DEST);
+               KDBG(MACHDBG_CODE(DBG_MACH_IPC, MACH_IPC_KMSG_INFO) | DBG_FUNC_END, MACH_SEND_INVALID_DEST);
                return MACH_MSG_SUCCESS;
        }
 
@@ -1962,13 +2045,14 @@ retry:
                 * the message as a successful delivery.
                 */
 #if MACH_FLIPC
-        if (MACH_NODE_VALID(kmsg->ikm_node) && FPORT_VALID(port->ip_messages.imq_fport))
-            flipc_msg_ack(kmsg->ikm_node, &port->ip_messages, FALSE);
+               if (MACH_NODE_VALID(kmsg->ikm_node) && FPORT_VALID(port->ip_messages.imq_fport)) {
+                       flipc_msg_ack(kmsg->ikm_node, &port->ip_messages, FALSE);
+               }
 #endif
                ip_release(port); /* JMM - Future: release right, not just ref */
                kmsg->ikm_header->msgh_remote_port = MACH_PORT_NULL;
                ipc_kmsg_destroy(kmsg);
-               KDBG(MACHDBG_CODE(DBG_MACH_IPC,MACH_IPC_KMSG_INFO) | DBG_FUNC_END, error);
+               KDBG(MACHDBG_CODE(DBG_MACH_IPC, MACH_IPC_KMSG_INFO) | DBG_FUNC_END, error);
                return MACH_MSG_SUCCESS;
        }
        return error;
@@ -1990,12 +2074,12 @@ retry:
 
 mach_msg_return_t
 ipc_kmsg_put(
-       ipc_kmsg_t              kmsg,
-       mach_msg_option_t       option,
-       mach_vm_address_t       rcv_addr,
-       mach_msg_size_t         rcv_size,
-       mach_msg_size_t         trailer_size,
-       mach_msg_size_t         *sizep)
+       ipc_kmsg_t              kmsg,
+       mach_msg_option_t       option,
+       mach_vm_address_t       rcv_addr,
+       mach_msg_size_t         rcv_size,
+       mach_msg_size_t         trailer_size,
+       mach_msg_size_t         *sizep)
 {
        mach_msg_size_t size = kmsg->ikm_header->msgh_size + trailer_size;
        mach_msg_return_t mr;
@@ -2004,37 +2088,37 @@ ipc_kmsg_put(
 
 
        DEBUG_KPRINT_SYSCALL_IPC("ipc_kmsg_put header:\n"
-                                                        "  size:               0x%.8x\n"
-                                                        "  bits:               0x%.8x\n"
-                                                        "  remote_port:        %p\n"
-                                                        "  local_port: %p\n"
-                                                        "  voucher_port:       0x%.8x\n"
-                                                        "  id:         %.8d\n",
-                                                        kmsg->ikm_header->msgh_size,
-                                                        kmsg->ikm_header->msgh_bits,
-                                                        kmsg->ikm_header->msgh_remote_port,
-                                                        kmsg->ikm_header->msgh_local_port,
-                                                        kmsg->ikm_header->msgh_voucher_port,
-                                                        kmsg->ikm_header->msgh_id);
+           "  size:            0x%.8x\n"
+           "  bits:            0x%.8x\n"
+           "  remote_port:     %p\n"
+           "  local_port:      %p\n"
+           "  voucher_port:    0x%.8x\n"
+           "  id:              %.8d\n",
+           kmsg->ikm_header->msgh_size,
+           kmsg->ikm_header->msgh_bits,
+           kmsg->ikm_header->msgh_remote_port,
+           kmsg->ikm_header->msgh_local_port,
+           kmsg->ikm_header->msgh_voucher_port,
+           kmsg->ikm_header->msgh_id);
 
 #if defined(__LP64__)
-       if (current_task() != kernel_task) { /* don't if receiver expects fully-cooked in-kernel msg; ux_exception */
-               mach_msg_legacy_header_t *legacy_header = 
-                       (mach_msg_legacy_header_t *)((vm_offset_t)(kmsg->ikm_header) + LEGACY_HEADER_SIZE_DELTA);
-
-               mach_msg_bits_t         bits            = kmsg->ikm_header->msgh_bits;
-               mach_msg_size_t         msg_size        = kmsg->ikm_header->msgh_size;
-               mach_port_name_t        remote_port     = CAST_MACH_PORT_TO_NAME(kmsg->ikm_header->msgh_remote_port);
-               mach_port_name_t        local_port      = CAST_MACH_PORT_TO_NAME(kmsg->ikm_header->msgh_local_port);
-               mach_port_name_t        voucher_port    = kmsg->ikm_header->msgh_voucher_port;
-               mach_msg_id_t           id                      = kmsg->ikm_header->msgh_id;
-
-               legacy_header->msgh_id                  = id;
+       if (current_task() != kernel_task) { /* don't if receiver expects fully-cooked in-kernel msg; */
+               mach_msg_legacy_header_t *legacy_header =
+                   (mach_msg_legacy_header_t *)((vm_offset_t)(kmsg->ikm_header) + LEGACY_HEADER_SIZE_DELTA);
+
+               mach_msg_bits_t         bits            = kmsg->ikm_header->msgh_bits;
+               mach_msg_size_t         msg_size        = kmsg->ikm_header->msgh_size;
+               mach_port_name_t        remote_port     = CAST_MACH_PORT_TO_NAME(kmsg->ikm_header->msgh_remote_port);
+               mach_port_name_t        local_port      = CAST_MACH_PORT_TO_NAME(kmsg->ikm_header->msgh_local_port);
+               mach_port_name_t        voucher_port    = kmsg->ikm_header->msgh_voucher_port;
+               mach_msg_id_t           id                      = kmsg->ikm_header->msgh_id;
+
+               legacy_header->msgh_id                  = id;
                legacy_header->msgh_local_port = local_port;
                legacy_header->msgh_remote_port = remote_port;
                legacy_header->msgh_voucher_port = voucher_port;
-               legacy_header->msgh_size                = msg_size - LEGACY_HEADER_SIZE_DELTA;
-               legacy_header->msgh_bits                = bits;
+               legacy_header->msgh_size                = msg_size - LEGACY_HEADER_SIZE_DELTA;
+               legacy_header->msgh_bits                = bits;
 
                size -= LEGACY_HEADER_SIZE_DELTA;
                kmsg->ikm_header = (mach_msg_header_t *)legacy_header;
@@ -2046,15 +2130,14 @@ ipc_kmsg_put(
        if (DEBUG_KPRINT_SYSCALL_PREDICATE(DEBUG_KPRINT_SYSCALL_IPC_MASK)) {
                kprintf("ipc_kmsg_put header+body: %d\n", (size));
                uint32_t i;
-               for(i=0;i*4 < size;i++)
-               {
-                       kprintf("%.4x\n",((uint32_t *)kmsg->ikm_header)[i]);
+               for (i = 0; i * 4 < size; i++) {
+                       kprintf("%.4x\n", ((uint32_t *)kmsg->ikm_header)[i]);
                }
-               kprintf("type: %d\n", ((mach_msg_type_descriptor_t *)(((mach_msg_base_t *)kmsg->ikm_header)+1))->type);
+               kprintf("type: %d\n", ((mach_msg_type_descriptor_t *)(((mach_msg_base_t *)kmsg->ikm_header) + 1))->type);
        }
        __unreachable_ok_pop
 
-        /* Re-Compute target address if using stack-style delivery */
+       /* Re-Compute target address if using stack-style delivery */
        if (option & MACH_RCV_STACK) {
                rcv_addr += rcv_size - size;
        }
@@ -2062,20 +2145,22 @@ ipc_kmsg_put(
        if (copyoutmsg((const char *) kmsg->ikm_header, rcv_addr, size)) {
                mr = MACH_RCV_INVALID_DATA;
                size = 0;
-       } else
+       } else {
                mr = MACH_MSG_SUCCESS;
+       }
 
-       KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_IPC,MACH_IPC_KMSG_LINK) | DBG_FUNC_NONE,
-                             (rcv_addr >= VM_MIN_KERNEL_AND_KEXT_ADDRESS ||
-                              rcv_addr + size >= VM_MIN_KERNEL_AND_KEXT_ADDRESS) ? (uintptr_t)0 : (uintptr_t)rcv_addr,
-                             VM_KERNEL_ADDRPERM((uintptr_t)kmsg),
-                             1 /* this is on the receive/copyout path */,
-                             0,
-                             0);
+       KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_IPC, MACH_IPC_KMSG_LINK) | DBG_FUNC_NONE,
+           (rcv_addr >= VM_MIN_KERNEL_AND_KEXT_ADDRESS ||
+           rcv_addr + size >= VM_MIN_KERNEL_AND_KEXT_ADDRESS) ? (uintptr_t)0 : (uintptr_t)rcv_addr,
+           VM_KERNEL_ADDRPERM((uintptr_t)kmsg),
+           1 /* this is on the receive/copyout path */,
+           0,
+           0);
        ipc_kmsg_free(kmsg);
 
-       if (sizep)
+       if (sizep) {
                *sizep = size;
+       }
        return mr;
 }
 
@@ -2091,16 +2176,29 @@ ipc_kmsg_put(
 
 void
 ipc_kmsg_put_to_kernel(
-       mach_msg_header_t       *msg,
-       ipc_kmsg_t              kmsg,
-       mach_msg_size_t         size)
+       mach_msg_header_t       *msg,
+       ipc_kmsg_t              kmsg,
+       mach_msg_size_t         size)
 {
        (void) memcpy((void *) msg, (const void *) kmsg->ikm_header, size);
 
        ipc_kmsg_free(kmsg);
 }
 
-unsigned long pthread_priority_canonicalize(unsigned long priority, boolean_t propagation);
+static mach_msg_priority_t
+ipc_get_current_thread_priority(void)
+{
+       thread_t thread = current_thread();
+       thread_qos_t qos;
+       int relpri;
+
+       qos = thread_get_requested_qos(thread, &relpri);
+       if (!qos) {
+               qos = thread_user_promotion_qos_for_pri(thread->base_pri);
+               relpri = 0;
+       }
+       return (mach_msg_priority_t)_pthread_priority_make_from_thread_qos(qos, relpri, 0);
+}
 
 static kern_return_t
 ipc_kmsg_set_qos(
@@ -2109,76 +2207,258 @@ ipc_kmsg_set_qos(
        mach_msg_priority_t override)
 {
        kern_return_t kr;
-       unsigned long flags = 0;
        ipc_port_t special_reply_port = kmsg->ikm_header->msgh_local_port;
        ipc_port_t dest_port = kmsg->ikm_header->msgh_remote_port;
 
        kr = ipc_get_pthpriority_from_kmsg_voucher(kmsg, &kmsg->ikm_qos);
        if (kr != KERN_SUCCESS) {
-               kmsg->ikm_qos = MACH_MSG_PRIORITY_UNSPECIFIED;
+               if (options & MACH_SEND_PROPAGATE_QOS) {
+                       kmsg->ikm_qos = ipc_get_current_thread_priority();
+               } else {
+                       kmsg->ikm_qos = MACH_MSG_PRIORITY_UNSPECIFIED;
+               }
        }
        kmsg->ikm_qos_override = kmsg->ikm_qos;
 
        if (options & MACH_SEND_OVERRIDE) {
-               unsigned long canonical;
-               mach_msg_priority_t canon;
-
-               canonical = pthread_priority_canonicalize(override, TRUE);
-               canon = (mach_msg_priority_t)canonical;
-               if (canon > kmsg->ikm_qos)
-                       kmsg->ikm_qos_override = canon;
+               pthread_priority_t pp = _pthread_priority_normalize_for_ipc(override);
+               if (pp > kmsg->ikm_qos) {
+                       kmsg->ikm_qos_override = (mach_msg_priority_t)pp;
+               }
        }
 
        kr = KERN_SUCCESS;
-       if ((options & MACH_SEND_SYNC_OVERRIDE)) {
-               if (IP_VALID(special_reply_port) &&
-                   MACH_MSGH_BITS_LOCAL(kmsg->ikm_header->msgh_bits) == MACH_MSG_TYPE_PORT_SEND_ONCE) {
+
+       if (IP_VALID(special_reply_port) &&
+           MACH_MSGH_BITS_LOCAL(kmsg->ikm_header->msgh_bits) == MACH_MSG_TYPE_PORT_SEND_ONCE) {
+               if ((options & MACH_SEND_SYNC_OVERRIDE)) {
+                       boolean_t sync_bootstrap_checkin = !!(options & MACH_SEND_SYNC_BOOTSTRAP_CHECKIN);
                        /*
-                        * Update the sync override count if the reply port is a special reply port,
-                        * link the destination port to special reply port and update the qos count
-                        * of destination port.
-                        *
-                        * Use the qos value passed by voucher and not the one passed by notify field.
+                        * Link the destination port to special reply port and make sure that
+                        * dest port has a send turnstile, else allocate one.
                         */
-                       kr = ipc_port_link_special_reply_port_with_qos(special_reply_port, dest_port,
-                               thread_qos_from_pthread_priority(kmsg->ikm_qos, &flags));
-               } else {
-                       kr = KERN_FAILURE;
+                       ipc_port_link_special_reply_port(special_reply_port, dest_port, sync_bootstrap_checkin);
                }
        }
        return kr;
 }
 
+static inline void
+ipc_kmsg_allow_immovable_send(
+       ipc_kmsg_t   kmsg,
+       ipc_entry_t  dest_entry)
+{
+       ipc_object_t object = dest_entry->ie_object;
+       /*
+        *      If the dest port is a kobject, allow copyin of immovable send
+        *      rights in the message body to succeed
+        */
+       if (IO_VALID(object) && io_is_kobject(object)) {
+               kmsg->ikm_flags |= IPC_KMSG_FLAGS_ALLOW_IMMOVABLE_SEND;
+       }
+}
+
 /*
- *     Routine:        ipc_kmsg_copyin_header
+ *     Routine:        ipc_kmsg_link_reply_context_locked
  *     Purpose:
- *             "Copy-in" port rights in the header of a message.
- *             Operates atomically; if it doesn't succeed the
- *             message header and the space are left untouched.
- *             If it does succeed the remote/local port fields
- *             contain object pointers instead of port names,
- *             and the bits field is updated.  The destination port
- *             will be a valid port pointer.
- *
+ *             Link any required context from the sending voucher
+ *             to the reply port. The ipc_kmsg_copyin function will
+ *             enforce that the sender calls mach_msg in this context.
  *     Conditions:
- *             Nothing locked.
- *     Returns:
- *             MACH_MSG_SUCCESS        Successful copyin.
- *             MACH_SEND_INVALID_HEADER
- *                     Illegal value in the message header bits.
- *             MACH_SEND_INVALID_DEST  The space is dead.
- *             MACH_SEND_INVALID_DEST  Can't copyin destination port.
- *                     (Either KERN_INVALID_NAME or KERN_INVALID_RIGHT.)
- *             MACH_SEND_INVALID_REPLY Can't copyin reply port.
- *                     (Either KERN_INVALID_NAME or KERN_INVALID_RIGHT.)
+ *             reply port is locked
  */
+static void
+ipc_kmsg_link_reply_context_locked(
+       ipc_port_t reply_port,
+       ipc_port_t voucher_port)
+{
+       kern_return_t __assert_only kr;
+       uint32_t persona_id = 0;
+       ipc_voucher_t voucher;
 
-mach_msg_return_t
-ipc_kmsg_copyin_header(
-       ipc_kmsg_t              kmsg,
-       ipc_space_t             space,
+       ip_lock_held(reply_port);
+
+       if (!ip_active(reply_port)) {
+               return;
+       }
+
+       voucher = convert_port_to_voucher(voucher_port);
+
+       kr = bank_get_bank_ledger_thread_group_and_persona(voucher, NULL, NULL, &persona_id);
+       assert(kr == KERN_SUCCESS);
+       ipc_voucher_release(voucher);
+
+       if (persona_id == 0 || persona_id == PERSONA_ID_NONE) {
+               /* there was no persona context to record */
+               return;
+       }
+
+       /*
+        * Set the persona_id as the context on the reply port.
+        * This will force the thread that replies to have adopted a voucher
+        * with a matching persona.
+        */
+       reply_port->ip_reply_context = persona_id;
+
+       return;
+}
+
+static kern_return_t
+ipc_kmsg_validate_reply_port_locked(ipc_port_t reply_port, mach_msg_option_t options)
+{
+       ip_lock_held(reply_port);
+
+       if (!ip_active(reply_port)) {
+               /*
+                * Ideally, we would enforce that the reply receive right is
+                * active, but asynchronous XPC cancellation destroys the
+                * receive right, so we just have to return success here.
+                */
+               return KERN_SUCCESS;
+       }
+
+       if (options & MACH_SEND_MSG) {
+               /*
+                * If the rely port is active, then it should not be
+                * in-transit, and the receive right should be in the caller's
+                * IPC space.
+                */
+               if (!reply_port->ip_receiver_name || reply_port->ip_receiver != current_task()->itk_space) {
+                       return KERN_INVALID_CAPABILITY;
+               }
+
+               /*
+                * A port used as a reply port in an RPC should have exactly 1
+                * extant send-once right which we either just made or are
+                * moving as part of the IPC.
+                */
+               if (reply_port->ip_sorights != 1) {
+                       return KERN_INVALID_CAPABILITY;
+               }
+               /*
+                * XPC uses an extra send-right to keep the name of the reply
+                * right around through cancellation.  That makes it harder to
+                * enforce a particular semantic kere, so for now, we say that
+                * you can have a maximum of 1 send right (in addition to your
+                * send once right). In the future, it would be great to lock
+                * this down even further.
+                */
+               if (reply_port->ip_srights > 1) {
+                       return KERN_INVALID_CAPABILITY;
+               }
+
+               /*
+                * The sender can also specify that the receive right should
+                * be immovable. Note that this check only applies to
+                * send-only operations. Combined send/receive or rcv-only
+                * operations can specify an immovable receive right by
+                * opt-ing into guarded descriptors (MACH_RCV_GUARDED_DESC)
+                * and using the MACH_MSG_STRICT_REPLY options flag.
+                */
+               if (MACH_SEND_REPLY_IS_IMMOVABLE(options)) {
+                       if (!reply_port->ip_immovable_receive) {
+                               return KERN_INVALID_CAPABILITY;
+                       }
+               }
+       }
+
+       /*
+        * don't enforce this yet: need a better way of indicating the
+        * receiver wants this...
+        */
+#if 0
+       if (MACH_RCV_WITH_IMMOVABLE_REPLY(options)) {
+               if (!reply_port->ip_immovable_receive) {
+                       return KERN_INVALID_CAPABILITY;
+               }
+       }
+#endif /* 0  */
+
+       return KERN_SUCCESS;
+}
+
+/*
+ *     Routine:        ipc_kmsg_validate_reply_context_locked
+ *     Purpose:
+ *             Validate that the current thread is running in the context
+ *             required by the destination port.
+ *     Conditions:
+ *             dest_port is locked
+ *     Returns:
+ *             MACH_MSG_SUCCESS on success.
+ *             On error, an EXC_GUARD exception is also raised.
+ *             This function *always* resets the port reply context.
+ */
+static mach_msg_return_t
+ipc_kmsg_validate_reply_context_locked(
+       mach_msg_option_t option,
+       ipc_port_t dest_port,
+       ipc_voucher_t voucher,
+       mach_port_name_t voucher_name)
+{
+       uint32_t dest_ctx = dest_port->ip_reply_context;
+       dest_port->ip_reply_context = 0;
+
+       if (!ip_active(dest_port)) {
+               return MACH_MSG_SUCCESS;
+       }
+
+       if (voucher == IPC_VOUCHER_NULL || !MACH_PORT_VALID(voucher_name)) {
+               if ((option & MACH_SEND_KERNEL) == 0) {
+                       mach_port_guard_exception(voucher_name, 0,
+                           (MPG_FLAGS_STRICT_REPLY_INVALID_VOUCHER | dest_ctx),
+                           kGUARD_EXC_STRICT_REPLY);
+               }
+               return MACH_SEND_INVALID_CONTEXT;
+       }
+
+       kern_return_t __assert_only kr;
+       uint32_t persona_id = 0;
+       kr = bank_get_bank_ledger_thread_group_and_persona(voucher, NULL, NULL, &persona_id);
+       assert(kr == KERN_SUCCESS);
+
+       if (dest_ctx != persona_id) {
+               if ((option & MACH_SEND_KERNEL) == 0) {
+                       mach_port_guard_exception(voucher_name, 0,
+                           (MPG_FLAGS_STRICT_REPLY_MISMATCHED_PERSONA | ((((uint64_t)persona_id << 32) & MPG_FLAGS_STRICT_REPLY_MASK) | dest_ctx)),
+                           kGUARD_EXC_STRICT_REPLY);
+               }
+               return MACH_SEND_INVALID_CONTEXT;
+       }
+
+       return MACH_MSG_SUCCESS;
+}
+
+/*
+ *     Routine:        ipc_kmsg_copyin_header
+ *     Purpose:
+ *             "Copy-in" port rights in the header of a message.
+ *             Operates atomically; if it doesn't succeed the
+ *             message header and the space are left untouched.
+ *             If it does succeed the remote/local port fields
+ *             contain object pointers instead of port names,
+ *             and the bits field is updated.  The destination port
+ *             will be a valid port pointer.
+ *
+ *     Conditions:
+ *             Nothing locked.
+ *     Returns:
+ *             MACH_MSG_SUCCESS        Successful copyin.
+ *             MACH_SEND_INVALID_HEADER
+ *                     Illegal value in the message header bits.
+ *             MACH_SEND_INVALID_DEST  The space is dead.
+ *             MACH_SEND_INVALID_DEST  Can't copyin destination port.
+ *                     (Either KERN_INVALID_NAME or KERN_INVALID_RIGHT.)
+ *             MACH_SEND_INVALID_REPLY Can't copyin reply port.
+ *                     (Either KERN_INVALID_NAME or KERN_INVALID_RIGHT.)
+ */
+
+mach_msg_return_t
+ipc_kmsg_copyin_header(
+       ipc_kmsg_t              kmsg,
+       ipc_space_t             space,
        mach_msg_priority_t override,
-       mach_msg_option_t       *optionp)
+       mach_msg_option_t       *optionp)
 {
        mach_msg_header_t *msg = kmsg->ikm_header;
        mach_msg_bits_t mbits = msg->msgh_bits & MACH_MSGH_BITS_USER;
@@ -2210,12 +2490,14 @@ ipc_kmsg_copyin_header(
        if ((mbits != msg->msgh_bits) ||
            (!MACH_MSG_TYPE_PORT_ANY_SEND(dest_type)) ||
            ((reply_type == 0) ?
-            (reply_name != MACH_PORT_NULL) :
-            !MACH_MSG_TYPE_PORT_ANY_SEND(reply_type)))
+           (reply_name != MACH_PORT_NULL) :
+           !MACH_MSG_TYPE_PORT_ANY_SEND(reply_type))) {
                return MACH_SEND_INVALID_HEADER;
+       }
 
-       if (!MACH_PORT_VALID(dest_name))
+       if (!MACH_PORT_VALID(dest_name)) {
                return MACH_SEND_INVALID_DEST;
+       }
 
        is_write_lock(space);
        if (!is_active(space)) {
@@ -2230,22 +2512,27 @@ ipc_kmsg_copyin_header(
         *      actually copy in until we validate destination and reply.
         */
        if (voucher_type != MACH_MSGH_BITS_ZERO) {
-
                voucher_name = msg->msgh_voucher_port;
 
                if (voucher_name == MACH_PORT_DEAD ||
                    (voucher_type != MACH_MSG_TYPE_MOVE_SEND &&
-                    voucher_type != MACH_MSG_TYPE_COPY_SEND)) {
+                   voucher_type != MACH_MSG_TYPE_COPY_SEND)) {
                        is_write_unlock(space);
+                       if ((*optionp & MACH_SEND_KERNEL) == 0) {
+                               mach_port_guard_exception(voucher_name, 0, 0, kGUARD_EXC_SEND_INVALID_VOUCHER);
+                       }
                        return MACH_SEND_INVALID_VOUCHER;
                }
 
                if (voucher_name != MACH_PORT_NULL) {
                        voucher_entry = ipc_entry_lookup(space, voucher_name);
-                       if (voucher_entry == IE_NULL || 
+                       if (voucher_entry == IE_NULL ||
                            (voucher_entry->ie_bits & MACH_PORT_TYPE_SEND) == 0 ||
                            io_kotype(voucher_entry->ie_object) != IKOT_VOUCHER) {
                                is_write_unlock(space);
+                               if ((*optionp & MACH_SEND_KERNEL) == 0) {
+                                       mach_port_guard_exception(voucher_name, 0, 0, kGUARD_EXC_SEND_INVALID_VOUCHER);
+                               }
                                return MACH_SEND_INVALID_VOUCHER;
                        }
                } else {
@@ -2253,13 +2540,29 @@ ipc_kmsg_copyin_header(
                }
        }
 
+       if (enforce_strict_reply && MACH_SEND_WITH_STRICT_REPLY(*optionp) &&
+           (!MACH_PORT_VALID(reply_name) ||
+           ((reply_type != MACH_MSG_TYPE_MAKE_SEND_ONCE) && (reply_type != MACH_MSG_TYPE_MOVE_SEND_ONCE))
+           )) {
+               /*
+                * The caller cannot enforce a reply context with an invalid
+                * reply port name, or a non-send_once reply disposition.
+                */
+               is_write_unlock(space);
+               if ((*optionp & MACH_SEND_KERNEL) == 0) {
+                       mach_port_guard_exception(reply_name, 0,
+                           (MPG_FLAGS_STRICT_REPLY_INVALID_REPLY_DISP | reply_type),
+                           kGUARD_EXC_STRICT_REPLY);
+               }
+               return MACH_SEND_INVALID_REPLY;
+       }
+
        /*
         *      Handle combinations of validating destination and reply; along
         *      with copying in destination, reply, and voucher in an atomic way.
         */
 
        if (dest_name == voucher_name) {
-
                /*
                 *      If the destination name is the same as the voucher name,
                 *      the voucher_entry must already be known.  Either that or
@@ -2269,6 +2572,8 @@ ipc_kmsg_copyin_header(
                if (dest_entry == IE_NULL) {
                        goto invalid_dest;
                }
+               /* Check if dest port allows immovable send rights to be sent in the kmsg body */
+               ipc_kmsg_allow_immovable_send(kmsg, dest_entry);
 
                /*
                 *      Make sure a future copyin of the reply port will succeed.
@@ -2287,49 +2592,47 @@ ipc_kmsg_copyin_header(
                                goto invalid_reply;
                        }
                        assert(dest_entry != reply_entry); /* names are not equal */
-                       if (!ipc_right_copyin_check(space, reply_name, reply_entry, reply_type)) {
+                       if (!ipc_right_copyin_check_reply(space, reply_name, reply_entry, reply_type)) {
                                goto invalid_reply;
                        }
                }
 
-               /* 
-                *      Do the joint copyin of the dest disposition and 
+               /*
+                *      Do the joint copyin of the dest disposition and
                 *      voucher disposition from the one entry/port.  We
                 *      already validated that the voucher copyin would
                 *      succeed (above).  So, any failure in combining
                 *      the copyins can be blamed on the destination.
                 */
                kr = ipc_right_copyin_two(space, dest_name, dest_entry,
-                                         dest_type, voucher_type,
-                                         &dest_port, &dest_soright,
-                                         &release_port);
+                   dest_type, voucher_type, &dest_port, &dest_soright,
+                   &release_port);
                if (kr != KERN_SUCCESS) {
                        assert(kr != KERN_INVALID_CAPABILITY);
                        goto invalid_dest;
                }
-               voucher_port = (ipc_port_t)dest_port;
+               voucher_port = ip_object_to_port(dest_port);
 
-               /* 
-                * could not have been one of these dispositions, 
+               /*
+                * could not have been one of these dispositions,
                 * validated the port was a true kernel voucher port above,
                 * AND was successfully able to copyin both dest and voucher.
                 */
                assert(dest_type != MACH_MSG_TYPE_MAKE_SEND);
                assert(dest_type != MACH_MSG_TYPE_MAKE_SEND_ONCE);
                assert(dest_type != MACH_MSG_TYPE_MOVE_SEND_ONCE);
-               
+
                /*
                 *      Perform the delayed reply right copyin (guaranteed success).
                 */
                if (reply_entry != IE_NULL) {
                        kr = ipc_right_copyin(space, reply_name, reply_entry,
-                                             reply_type, TRUE,
-                                             &reply_port, &reply_soright,
-                                             &release_port, &assertcnt);
+                           reply_type, IPC_RIGHT_COPYIN_FLAGS_DEADOK,
+                           &reply_port, &reply_soright,
+                           &release_port, &assertcnt, 0, NULL);
                        assert(assertcnt == 0);
                        assert(kr == KERN_SUCCESS);
                }
-
        } else {
                if (dest_name == reply_name) {
                        /*
@@ -2343,25 +2646,31 @@ ipc_kmsg_copyin_header(
                        if (dest_entry == IE_NULL) {
                                goto invalid_dest;
                        }
+                       ipc_kmsg_allow_immovable_send(kmsg, dest_entry);
+
                        reply_entry = dest_entry;
                        assert(reply_type != 0); /* because name not null */
 
-                       /* 
-                        *      Do the joint copyin of the dest disposition and 
+                       /*
+                        *      Pre-validate that the reply right can be copied in by itself
+                        */
+                       if (!ipc_right_copyin_check_reply(space, reply_name, reply_entry, reply_type)) {
+                               goto invalid_reply;
+                       }
+
+                       /*
+                        *      Do the joint copyin of the dest disposition and
                         *      reply disposition from the one entry/port.
                         */
                        kr = ipc_right_copyin_two(space, dest_name, dest_entry,
-                                                 dest_type, reply_type,
-                                                 &dest_port, &dest_soright,
-                                                 &release_port);
+                           dest_type, reply_type, &dest_port, &dest_soright,
+                           &release_port);
                        if (kr == KERN_INVALID_CAPABILITY) {
                                goto invalid_reply;
                        } else if (kr != KERN_SUCCESS) {
                                goto invalid_dest;
                        }
                        reply_port = dest_port;
-
-
                } else {
                        /*
                         *      Handle destination and reply independently, as
@@ -2394,6 +2703,7 @@ ipc_kmsg_copyin_header(
                                goto invalid_dest;
                        }
                        assert(dest_entry != voucher_entry);
+                       ipc_kmsg_allow_immovable_send(kmsg, dest_entry);
 
                        /*
                         *      Make sure reply port entry is valid before dest copyin.
@@ -2409,7 +2719,7 @@ ipc_kmsg_copyin_header(
                                assert(dest_entry != reply_entry); /* names are not equal */
                                assert(reply_type != 0); /* because reply_name not null */
 
-                               if (!ipc_right_copyin_check(space, reply_name, reply_entry, reply_type)) {
+                               if (!ipc_right_copyin_check_reply(space, reply_name, reply_entry, reply_type)) {
                                        goto invalid_reply;
                                }
                        }
@@ -2418,9 +2728,10 @@ ipc_kmsg_copyin_header(
                         *      copyin the destination.
                         */
                        kr = ipc_right_copyin(space, dest_name, dest_entry,
-                                             dest_type, FALSE,
-                                             &dest_port, &dest_soright,
-                                             &release_port, &assertcnt);
+                           dest_type, (IPC_RIGHT_COPYIN_FLAGS_ALLOW_IMMOVABLE_SEND |
+                           IPC_RIGHT_COPYIN_FLAGS_ALLOW_DEAD_SEND_ONCE),
+                           &dest_port, &dest_soright,
+                           &release_port, &assertcnt, 0, NULL);
                        assert(assertcnt == 0);
                        if (kr != KERN_SUCCESS) {
                                goto invalid_dest;
@@ -2434,14 +2745,14 @@ ipc_kmsg_copyin_header(
                         */
                        if (MACH_PORT_VALID(reply_name)) {
                                kr = ipc_right_copyin(space, reply_name, reply_entry,
-                                                     reply_type, TRUE,
-                                                     &reply_port, &reply_soright,
-                                                     &release_port, &assertcnt);
+                                   reply_type, IPC_RIGHT_COPYIN_FLAGS_DEADOK,
+                                   &reply_port, &reply_soright,
+                                   &release_port, &assertcnt, 0, NULL);
                                assert(assertcnt == 0);
                                assert(kr == KERN_SUCCESS);
                        } else {
                                /* convert invalid name to equivalent ipc_object type */
-                               reply_port = (ipc_object_t)CAST_MACH_NAME_TO_PORT(reply_name);
+                               reply_port = ip_to_object(CAST_MACH_NAME_TO_PORT(reply_name));
                        }
                }
 
@@ -2451,15 +2762,15 @@ ipc_kmsg_copyin_header(
                 */
                if (IE_NULL != voucher_entry) {
                        kr = ipc_right_copyin(space, voucher_name, voucher_entry,
-                                             voucher_type, FALSE,
-                                             (ipc_object_t *)&voucher_port,
-                                             &voucher_soright,
-                                             &voucher_release_port,
-                                             &assertcnt);
+                           voucher_type, IPC_RIGHT_COPYIN_FLAGS_NONE,
+                           (ipc_object_t *)&voucher_port,
+                           &voucher_soright,
+                           &voucher_release_port,
+                           &assertcnt, 0, NULL);
                        assert(assertcnt == 0);
                        assert(KERN_SUCCESS == kr);
                        assert(IP_VALID(voucher_port));
-                       assert(ip_active(voucher_port));
+                       require_ip_active(voucher_port);
                }
        }
 
@@ -2472,8 +2783,9 @@ ipc_kmsg_copyin_header(
         * but reply and voucher must be distinct entries.
         */
        assert(IE_NULL != dest_entry);
-       if (IE_NULL != reply_entry)
+       if (IE_NULL != reply_entry) {
                assert(reply_entry != voucher_entry);
+       }
 
        if (IE_BITS_TYPE(dest_entry->ie_bits) == MACH_PORT_TYPE_NONE) {
                ipc_entry_dealloc(space, dest_name, dest_entry);
@@ -2508,27 +2820,28 @@ ipc_kmsg_copyin_header(
         * early (send may NOT have failed), but better than missing.  We assure
         * we won't miss by forcing MACH_SEND_ALWAYS if we got past arming.
         */
-       if (((*optionp & MACH_SEND_NOTIFY) != 0) && 
+       if (((*optionp & MACH_SEND_NOTIFY) != 0) &&
            dest_type != MACH_MSG_TYPE_PORT_SEND_ONCE &&
            dest_entry != IE_NULL && dest_entry->ie_request != IE_REQ_NONE) {
-               ipc_port_t dport = (ipc_port_t)dest_port;
+               ipc_port_t dport = ip_object_to_port(dest_port);
 
                assert(dport != IP_NULL);
                ip_lock(dport);
                if (ip_active(dport) && dport->ip_receiver != ipc_space_kernel) {
                        if (ip_full(dport)) {
 #if IMPORTANCE_INHERITANCE
-                               needboost = ipc_port_request_sparm(dport, dest_name, 
-                                                                  dest_entry->ie_request,
-                                                                  *optionp,
-                                                                  override);
-                               if (needboost == FALSE)
+                               needboost = ipc_port_request_sparm(dport, dest_name,
+                                   dest_entry->ie_request,
+                                   *optionp,
+                                   override);
+                               if (needboost == FALSE) {
                                        ip_unlock(dport);
+                               }
 #else
                                ipc_port_request_sparm(dport, dest_name,
-                                                      dest_entry->ie_request,
-                                                      *optionp,
-                                                                          override);
+                                   dest_entry->ie_request,
+                                   *optionp,
+                                   override);
                                ip_unlock(dport);
 #endif /* IMPORTANCE_INHERITANCE */
                        } else {
@@ -2543,13 +2856,13 @@ ipc_kmsg_copyin_header(
        is_write_unlock(space);
 
 #if IMPORTANCE_INHERITANCE
-       /* 
+       /*
         * If our request is the first boosting send-possible
         * notification this cycle, push the boost down the
         * destination port.
         */
        if (needboost == TRUE) {
-               ipc_port_t dport = (ipc_port_t)dest_port;
+               ipc_port_t dport = ip_object_to_port(dest_port);
 
                /* dport still locked from above */
                if (ipc_port_importance_delta(dport, IPID_OPTION_SENDPOSSIBLE, 1) == FALSE) {
@@ -2574,45 +2887,83 @@ ipc_kmsg_copyin_header(
         * qos, and apply any override before we enqueue the kmsg.
         */
        if (IP_VALID(voucher_port)) {
-
                kmsg->ikm_voucher = voucher_port;
                voucher_type = MACH_MSG_TYPE_MOVE_SEND;
        }
 
        msg->msgh_bits = MACH_MSGH_BITS_SET(dest_type, reply_type, voucher_type, mbits);
-       msg->msgh_remote_port = (ipc_port_t)dest_port;
-       msg->msgh_local_port = (ipc_port_t)reply_port;
+       msg->msgh_remote_port = ip_object_to_port(dest_port);
+       msg->msgh_local_port = ip_object_to_port(reply_port);
 
        /* capture the qos value(s) for the kmsg */
        ipc_kmsg_set_qos(kmsg, *optionp, override);
 
-       if (release_port != IP_NULL)
+       if (release_port != IP_NULL) {
                ip_release(release_port);
+       }
 
-       if (voucher_release_port != IP_NULL)
+       if (voucher_release_port != IP_NULL) {
                ip_release(voucher_release_port);
+       }
+
+       if (enforce_strict_reply && MACH_SEND_WITH_STRICT_REPLY(*optionp) && IP_VALID(msg->msgh_local_port)) {
+               /*
+                * We've already validated that the reply disposition is a
+                * [make/move] send-once. Ideally, we should enforce that the
+                * reply port is also not dead, but XPC asynchronous
+                * cancellation can make the reply port dead before we
+                * actually make it to the mach_msg send.
+                *
+                * Here, we ensure that if we have a non-dead reply port, then
+                * the reply port's receive right should not be in-transit,
+                * and should live in the caller's IPC space.
+                */
+               ipc_port_t rport = msg->msgh_local_port;
+               ip_lock(rport);
+               kr = ipc_kmsg_validate_reply_port_locked(rport, *optionp);
+               ip_unlock(rport);
+               if (kr != KERN_SUCCESS) {
+                       /*
+                        * no descriptors have been copied in yet, but the
+                        * full header has been copied in: clean it up
+                        */
+                       ipc_kmsg_clean_partial(kmsg, 0, NULL, 0, 0);
+                       if ((*optionp & MACH_SEND_KERNEL) == 0) {
+                               mach_port_guard_exception(reply_name, 0,
+                                   (MPG_FLAGS_STRICT_REPLY_INVALID_REPLY_PORT | kr),
+                                   kGUARD_EXC_STRICT_REPLY);
+                       }
+                       return MACH_SEND_INVALID_REPLY;
+               }
+       }
 
        return MACH_MSG_SUCCESS;
 
 invalid_reply:
        is_write_unlock(space);
 
-       if (release_port != IP_NULL)
+       if (release_port != IP_NULL) {
                ip_release(release_port);
+       }
 
        assert(voucher_port == IP_NULL);
        assert(voucher_soright == IP_NULL);
 
+       if ((*optionp & MACH_SEND_KERNEL) == 0) {
+               mach_port_guard_exception(reply_name, 0, 0, kGUARD_EXC_SEND_INVALID_REPLY);
+       }
        return MACH_SEND_INVALID_REPLY;
 
 invalid_dest:
        is_write_unlock(space);
 
-       if (release_port != IP_NULL)
+       if (release_port != IP_NULL) {
                ip_release(release_port);
+       }
 
-       if (reply_soright != IP_NULL)
+       if (reply_soright != IP_NULL) {
                ipc_notify_port_deleted(reply_soright, reply_name);
+       }
 
        assert(voucher_port == IP_NULL);
        assert(voucher_soright == IP_NULL);
@@ -2620,324 +2971,371 @@ invalid_dest:
        return MACH_SEND_INVALID_DEST;
 }
 
-mach_msg_descriptor_t *ipc_kmsg_copyin_port_descriptor(
-        volatile mach_msg_port_descriptor_t *dsc,
-        mach_msg_legacy_port_descriptor_t *user_dsc,
-        ipc_space_t space,
-        ipc_object_t dest,
-        ipc_kmsg_t kmsg,
-        mach_msg_return_t *mr);
-
-void ipc_print_type_name(
-   int type_name);
-mach_msg_descriptor_t *
+static mach_msg_descriptor_t *
 ipc_kmsg_copyin_port_descriptor(
-        volatile mach_msg_port_descriptor_t *dsc,
-        mach_msg_legacy_port_descriptor_t *user_dsc_in,
-        ipc_space_t space,
-        ipc_object_t dest,
-        ipc_kmsg_t kmsg,
-        mach_msg_return_t *mr)
+       volatile mach_msg_port_descriptor_t *dsc,
+       mach_msg_legacy_port_descriptor_t *user_dsc_in,
+       ipc_space_t space,
+       ipc_object_t dest,
+       ipc_kmsg_t kmsg,
+       mach_msg_option_t *optionp,
+       mach_msg_return_t *mr)
 {
-    volatile mach_msg_legacy_port_descriptor_t *user_dsc = user_dsc_in;
-    mach_msg_type_name_t       user_disp;
-    mach_msg_type_name_t       result_disp;
-    mach_port_name_t           name;
-    ipc_object_t                       object;
-
-    user_disp = user_dsc->disposition;
-    result_disp = ipc_object_copyin_type(user_disp);
-
-    name = (mach_port_name_t)user_dsc->name;
-    if (MACH_PORT_VALID(name)) {
-
-        kern_return_t kr = ipc_object_copyin(space, name, user_disp, &object);
-        if (kr != KERN_SUCCESS) {
-            *mr = MACH_SEND_INVALID_RIGHT;
-            return NULL;
-        }
-
-        if ((result_disp == MACH_MSG_TYPE_PORT_RECEIVE) &&
-                ipc_port_check_circularity((ipc_port_t) object,
-                    (ipc_port_t) dest)) {
-            kmsg->ikm_header->msgh_bits |= MACH_MSGH_BITS_CIRCULAR;
-        }
-        dsc->name = (ipc_port_t) object;
-    } else {
-        dsc->name = CAST_MACH_NAME_TO_PORT(name);
-    }
-    dsc->disposition = result_disp;
-    dsc->type = MACH_MSG_PORT_DESCRIPTOR;
-
-    dsc->pad_end = 0; // debug, unnecessary
-
-    return (mach_msg_descriptor_t *)(user_dsc_in+1);
+       volatile mach_msg_legacy_port_descriptor_t *user_dsc = user_dsc_in;
+       mach_msg_type_name_t        user_disp;
+       mach_msg_type_name_t        result_disp;
+       mach_port_name_t            name;
+       ipc_object_t                        object;
+
+       user_disp = user_dsc->disposition;
+       result_disp = ipc_object_copyin_type(user_disp);
+
+       name = (mach_port_name_t)user_dsc->name;
+       if (MACH_PORT_VALID(name)) {
+               kern_return_t kr = ipc_object_copyin(space, name, user_disp, &object, 0, NULL, kmsg->ikm_flags);
+               if (kr != KERN_SUCCESS) {
+                       if (((*optionp & MACH_SEND_KERNEL) == 0) && (kr == KERN_INVALID_RIGHT)) {
+                               mach_port_guard_exception(name, 0, 0, kGUARD_EXC_SEND_INVALID_RIGHT);
+                       }
+                       *mr = MACH_SEND_INVALID_RIGHT;
+                       return NULL;
+               }
+
+               if ((result_disp == MACH_MSG_TYPE_PORT_RECEIVE) &&
+                   ipc_port_check_circularity(ip_object_to_port(object),
+                   ip_object_to_port(dest))) {
+                       kmsg->ikm_header->msgh_bits |= MACH_MSGH_BITS_CIRCULAR;
+               }
+               dsc->name = ip_object_to_port(object);
+       } else {
+               dsc->name = CAST_MACH_NAME_TO_PORT(name);
+       }
+       dsc->disposition = result_disp;
+       dsc->type = MACH_MSG_PORT_DESCRIPTOR;
+
+       dsc->pad_end = 0;         // debug, unnecessary
+
+       return (mach_msg_descriptor_t *)(user_dsc_in + 1);
 }
 
-mach_msg_descriptor_t * ipc_kmsg_copyin_ool_descriptor(
-        mach_msg_ool_descriptor_t *dsc,
-        mach_msg_descriptor_t *user_dsc,
-        int is_64bit,
-        vm_offset_t *paddr,
-        vm_map_copy_t *copy,
-        vm_size_t *space_needed,
-        vm_map_t map,
-        mach_msg_return_t *mr);
-mach_msg_descriptor_t *
+static mach_msg_descriptor_t *
 ipc_kmsg_copyin_ool_descriptor(
-        mach_msg_ool_descriptor_t *dsc,
-        mach_msg_descriptor_t *user_dsc,
-        int is_64bit,
-        vm_offset_t *paddr,
-        vm_map_copy_t *copy,
-        vm_size_t *space_needed,
-        vm_map_t map,
-        mach_msg_return_t *mr)
+       mach_msg_ool_descriptor_t *dsc,
+       mach_msg_descriptor_t *user_dsc,
+       int is_64bit,
+       vm_offset_t *paddr,
+       vm_map_copy_t *copy,
+       vm_size_t *space_needed,
+       vm_map_t map,
+       __unused mach_msg_option_t *optionp,
+       mach_msg_return_t *mr)
 {
-    vm_size_t                          length;
-    boolean_t                          dealloc;
-    mach_msg_copy_options_t            copy_options;
-    mach_vm_offset_t           addr;
-    mach_msg_descriptor_type_t dsc_type;
-
-    if (is_64bit) {
-        mach_msg_ool_descriptor64_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
-
-        addr = (mach_vm_offset_t) user_ool_dsc->address;
-        length = user_ool_dsc->size;
-        dealloc = user_ool_dsc->deallocate;
-        copy_options = user_ool_dsc->copy;
-        dsc_type = user_ool_dsc->type;
-
-        user_dsc = (typeof(user_dsc))(user_ool_dsc+1);
-    } else {
-        mach_msg_ool_descriptor32_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
-
-        addr = CAST_USER_ADDR_T(user_ool_dsc->address);
-        dealloc = user_ool_dsc->deallocate;
-        copy_options = user_ool_dsc->copy;
-        dsc_type = user_ool_dsc->type;
-        length = user_ool_dsc->size;
-
-        user_dsc = (typeof(user_dsc))(user_ool_dsc+1);
-    }
-
-    dsc->size = (mach_msg_size_t)length;
-    dsc->deallocate = dealloc;
-    dsc->copy = copy_options;
-    dsc->type = dsc_type;
-
-    if (length == 0) {
-        dsc->address = NULL;
-    } else if ((length >= MSG_OOL_SIZE_SMALL) &&
-            (copy_options == MACH_MSG_PHYSICAL_COPY) && !dealloc) {
-
-        /*
-         * If the request is a physical copy and the source
-         * is not being deallocated, then allocate space
-         * in the kernel's pageable ipc copy map and copy
-         * the data in.  The semantics guarantee that the
-         * data will have been physically copied before
-         * the send operation terminates.  Thus if the data
-         * is not being deallocated, we must be prepared
-         * to page if the region is sufficiently large.
-         */
-        if (copyin(addr, (char *)*paddr, length)) {
-            *mr = MACH_SEND_INVALID_MEMORY;
-            return NULL;
-        }      
-
-        /*
-         * The kernel ipc copy map is marked no_zero_fill.
-         * If the transfer is not a page multiple, we need
-         * to zero fill the balance.
-         */
-        if (!page_aligned(length)) {
-            (void) memset((void *) (*paddr + length), 0,
-                    round_page(length) - length);
-        }
-        if (vm_map_copyin(ipc_kernel_copy_map, (vm_map_address_t)*paddr,
-                    (vm_map_size_t)length, TRUE, copy) != KERN_SUCCESS) {
-            *mr = MACH_MSG_VM_KERNEL;
-            return NULL;
-        }
-        dsc->address = (void *)*copy;
-        *paddr += round_page(length);
-        *space_needed -= round_page(length);
-    } else {
-
-        /*
-         * Make a vm_map_copy_t of the of the data.  If the
-         * data is small, this will do an optimized physical
-         * copy.  Otherwise, it will do a virtual copy.
-         *
-         * NOTE: A virtual copy is OK if the original is being
-         * deallocted, even if a physical copy was requested.
-         */
-        kern_return_t kr = vm_map_copyin(map, addr, 
-                (vm_map_size_t)length, dealloc, copy);
-        if (kr != KERN_SUCCESS) {
-            *mr = (kr == KERN_RESOURCE_SHORTAGE) ?
-                MACH_MSG_VM_KERNEL :
-                MACH_SEND_INVALID_MEMORY;
-            return NULL;
-        }
-        dsc->address = (void *)*copy;
-    }
-    return user_dsc;
+       vm_size_t                           length;
+       boolean_t                           dealloc;
+       mach_msg_copy_options_t             copy_options;
+       mach_vm_offset_t            addr;
+       mach_msg_descriptor_type_t  dsc_type;
+
+       if (is_64bit) {
+               mach_msg_ool_descriptor64_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
+
+               addr = (mach_vm_offset_t) user_ool_dsc->address;
+               length = user_ool_dsc->size;
+               dealloc = user_ool_dsc->deallocate;
+               copy_options = user_ool_dsc->copy;
+               dsc_type = user_ool_dsc->type;
+
+               user_dsc = (typeof(user_dsc))(user_ool_dsc + 1);
+       } else {
+               mach_msg_ool_descriptor32_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
+
+               addr = CAST_USER_ADDR_T(user_ool_dsc->address);
+               dealloc = user_ool_dsc->deallocate;
+               copy_options = user_ool_dsc->copy;
+               dsc_type = user_ool_dsc->type;
+               length = user_ool_dsc->size;
+
+               user_dsc = (typeof(user_dsc))(user_ool_dsc + 1);
+       }
+
+       dsc->size = (mach_msg_size_t)length;
+       dsc->deallocate = dealloc;
+       dsc->copy = copy_options;
+       dsc->type = dsc_type;
+
+       if (length == 0) {
+               dsc->address = NULL;
+       } else if ((length >= MSG_OOL_SIZE_SMALL) &&
+           (copy_options == MACH_MSG_PHYSICAL_COPY) && !dealloc) {
+               /*
+                * If the request is a physical copy and the source
+                * is not being deallocated, then allocate space
+                * in the kernel's pageable ipc copy map and copy
+                * the data in.  The semantics guarantee that the
+                * data will have been physically copied before
+                * the send operation terminates.  Thus if the data
+                * is not being deallocated, we must be prepared
+                * to page if the region is sufficiently large.
+                */
+               if (copyin(addr, (char *)*paddr, length)) {
+                       *mr = MACH_SEND_INVALID_MEMORY;
+                       return NULL;
+               }
+
+               /*
+                * The kernel ipc copy map is marked no_zero_fill.
+                * If the transfer is not a page multiple, we need
+                * to zero fill the balance.
+                */
+               if (!page_aligned(length)) {
+                       (void) memset((void *) (*paddr + length), 0,
+                           round_page(length) - length);
+               }
+               if (vm_map_copyin(ipc_kernel_copy_map, (vm_map_address_t)*paddr,
+                   (vm_map_size_t)length, TRUE, copy) != KERN_SUCCESS) {
+                       *mr = MACH_MSG_VM_KERNEL;
+                       return NULL;
+               }
+               dsc->address = (void *)*copy;
+               *paddr += round_page(length);
+               *space_needed -= round_page(length);
+       } else {
+               /*
+                * Make a vm_map_copy_t of the of the data.  If the
+                * data is small, this will do an optimized physical
+                * copy.  Otherwise, it will do a virtual copy.
+                *
+                * NOTE: A virtual copy is OK if the original is being
+                * deallocted, even if a physical copy was requested.
+                */
+               kern_return_t kr = vm_map_copyin(map, addr,
+                   (vm_map_size_t)length, dealloc, copy);
+               if (kr != KERN_SUCCESS) {
+                       *mr = (kr == KERN_RESOURCE_SHORTAGE) ?
+                           MACH_MSG_VM_KERNEL :
+                           MACH_SEND_INVALID_MEMORY;
+                       return NULL;
+               }
+               dsc->address = (void *)*copy;
+       }
+       return user_dsc;
 }
 
-mach_msg_descriptor_t * ipc_kmsg_copyin_ool_ports_descriptor(
-        mach_msg_ool_ports_descriptor_t *dsc,
-        mach_msg_descriptor_t *user_dsc,
-        int is_64bit,
-        vm_map_t map,
-        ipc_space_t space,
-        ipc_object_t dest,
-        ipc_kmsg_t kmsg,
-        mach_msg_return_t *mr);
-mach_msg_descriptor_t *
+static mach_msg_descriptor_t *
 ipc_kmsg_copyin_ool_ports_descriptor(
-        mach_msg_ool_ports_descriptor_t *dsc,
-        mach_msg_descriptor_t *user_dsc,
-        int is_64bit,
-        vm_map_t map,
-        ipc_space_t space,
-        ipc_object_t dest,
-        ipc_kmsg_t kmsg,
-        mach_msg_return_t *mr)
+       mach_msg_ool_ports_descriptor_t *dsc,
+       mach_msg_descriptor_t *user_dsc,
+       int is_64bit,
+       vm_map_t map,
+       ipc_space_t space,
+       ipc_object_t dest,
+       ipc_kmsg_t kmsg,
+       mach_msg_option_t *optionp,
+       mach_msg_return_t *mr)
 {
-    void                                       *data;
-    ipc_object_t                       *objects;
-    unsigned int                               i;
-    mach_vm_offset_t                           addr;
-    mach_msg_type_name_t               user_disp;
-    mach_msg_type_name_t               result_disp;
-    mach_msg_type_number_t                     count;
-    mach_msg_copy_options_t                    copy_option;
-    boolean_t                          deallocate;
-    mach_msg_descriptor_type_t      type;
-    vm_size_t                          ports_length, names_length;
-
-    if (is_64bit) {
-        mach_msg_ool_ports_descriptor64_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
-
-        addr = (mach_vm_offset_t)user_ool_dsc->address;
-        count = user_ool_dsc->count;
-        deallocate = user_ool_dsc->deallocate;
-        copy_option = user_ool_dsc->copy;
-        user_disp = user_ool_dsc->disposition;
-        type = user_ool_dsc->type;
-
-        user_dsc = (typeof(user_dsc))(user_ool_dsc+1);
-    } else {
-        mach_msg_ool_ports_descriptor32_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
-
-        addr = CAST_USER_ADDR_T(user_ool_dsc->address);
-        count = user_ool_dsc->count;
-        deallocate = user_ool_dsc->deallocate;
-        copy_option = user_ool_dsc->copy;
-        user_disp = user_ool_dsc->disposition;
-        type = user_ool_dsc->type;
-
-        user_dsc = (typeof(user_dsc))(user_ool_dsc+1);
-    }
-
-    dsc->deallocate = deallocate;
-    dsc->copy = copy_option;
-    dsc->type = type;
-    dsc->count = count;
-    dsc->address = NULL;  /* for now */
-
-    result_disp = ipc_object_copyin_type(user_disp);
-    dsc->disposition = result_disp;
-
-    /* We always do a 'physical copy', but you have to specify something valid */
-    if (copy_option != MACH_MSG_PHYSICAL_COPY &&
-        copy_option != MACH_MSG_VIRTUAL_COPY) {
-        *mr = MACH_SEND_INVALID_TYPE;
-        return NULL;
-    }
-
-    /* calculate length of data in bytes, rounding up */
-
-    if (os_mul_overflow(count, sizeof(mach_port_t), &ports_length)) {
-        *mr = MACH_SEND_TOO_LARGE;
-        return NULL;
-    }
-
-    if (os_mul_overflow(count, sizeof(mach_port_name_t), &names_length)) {
-        *mr = MACH_SEND_TOO_LARGE;
-        return NULL;
-    }
-
-    if (ports_length == 0) {
-        return user_dsc;
-    }
-
-    data = kalloc(ports_length);
-
-    if (data == NULL) {
-        *mr = MACH_SEND_NO_BUFFER;
-        return NULL;
-    }
-    
+       void *data;
+       ipc_object_t *objects;
+       unsigned int i;
+       mach_vm_offset_t addr;
+       mach_msg_type_name_t user_disp;
+       mach_msg_type_name_t result_disp;
+       mach_msg_type_number_t count;
+       mach_msg_copy_options_t copy_option;
+       boolean_t deallocate;
+       mach_msg_descriptor_type_t type;
+       vm_size_t ports_length, names_length;
+
+       if (is_64bit) {
+               mach_msg_ool_ports_descriptor64_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
+
+               addr = (mach_vm_offset_t)user_ool_dsc->address;
+               count = user_ool_dsc->count;
+               deallocate = user_ool_dsc->deallocate;
+               copy_option = user_ool_dsc->copy;
+               user_disp = user_ool_dsc->disposition;
+               type = user_ool_dsc->type;
+
+               user_dsc = (typeof(user_dsc))(user_ool_dsc + 1);
+       } else {
+               mach_msg_ool_ports_descriptor32_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
+
+               addr = CAST_USER_ADDR_T(user_ool_dsc->address);
+               count = user_ool_dsc->count;
+               deallocate = user_ool_dsc->deallocate;
+               copy_option = user_ool_dsc->copy;
+               user_disp = user_ool_dsc->disposition;
+               type = user_ool_dsc->type;
+
+               user_dsc = (typeof(user_dsc))(user_ool_dsc + 1);
+       }
+
+       dsc->deallocate = deallocate;
+       dsc->copy = copy_option;
+       dsc->type = type;
+       dsc->count = count;
+       dsc->address = NULL; /* for now */
+
+       result_disp = ipc_object_copyin_type(user_disp);
+       dsc->disposition = result_disp;
+
+       /* We always do a 'physical copy', but you have to specify something valid */
+       if (copy_option != MACH_MSG_PHYSICAL_COPY &&
+           copy_option != MACH_MSG_VIRTUAL_COPY) {
+               *mr = MACH_SEND_INVALID_TYPE;
+               return NULL;
+       }
+
+       /* calculate length of data in bytes, rounding up */
+
+       if (os_mul_overflow(count, sizeof(mach_port_t), &ports_length)) {
+               *mr = MACH_SEND_TOO_LARGE;
+               return NULL;
+       }
+
+       if (os_mul_overflow(count, sizeof(mach_port_name_t), &names_length)) {
+               *mr = MACH_SEND_TOO_LARGE;
+               return NULL;
+       }
+
+       if (ports_length == 0) {
+               return user_dsc;
+       }
+
+       data = kalloc(ports_length);
+
+       if (data == NULL) {
+               *mr = MACH_SEND_NO_BUFFER;
+               return NULL;
+       }
+
 #ifdef __LP64__
-    mach_port_name_t *names = &((mach_port_name_t *)data)[count];
+       mach_port_name_t *names = &((mach_port_name_t *)data)[count];
 #else
-    mach_port_name_t *names = ((mach_port_name_t *)data);
+       mach_port_name_t *names = ((mach_port_name_t *)data);
 #endif
 
-    if (copyinmap(map, addr, names, names_length) != KERN_SUCCESS) {
-        kfree(data, ports_length);
-        *mr = MACH_SEND_INVALID_MEMORY;
-        return NULL;
-    }
-
-    if (deallocate) {
-        (void) mach_vm_deallocate(map, addr, (mach_vm_size_t)ports_length);
-    }
-
-    objects = (ipc_object_t *) data;
-    dsc->address = data;
-
-    for ( i = 0; i < count; i++) {
-        mach_port_name_t name = names[i];
-        ipc_object_t object;
-
-        if (!MACH_PORT_VALID(name)) {
-            objects[i] = (ipc_object_t)CAST_MACH_NAME_TO_PORT(name);
-            continue;
-        }
-
-        kern_return_t kr = ipc_object_copyin(space, name, user_disp, &object);
-
-        if (kr != KERN_SUCCESS) {
-            unsigned int j;
-
-            for(j = 0; j < i; j++) {
-                object = objects[j];
-                if (IPC_OBJECT_VALID(object))
-                    ipc_object_destroy(object, result_disp);
-            }
-            kfree(data, ports_length);
-            dsc->address = NULL;
-            *mr = MACH_SEND_INVALID_RIGHT;
-            return NULL;
-        }
-
-        if ((dsc->disposition == MACH_MSG_TYPE_PORT_RECEIVE) &&
-                ipc_port_check_circularity(
-                    (ipc_port_t) object,
-                    (ipc_port_t) dest))
-            kmsg->ikm_header->msgh_bits |= MACH_MSGH_BITS_CIRCULAR;
-
-        objects[i] = object;
-    }
-
-    return user_dsc;
+       if (copyinmap(map, addr, names, names_length) != KERN_SUCCESS) {
+               kfree(data, ports_length);
+               *mr = MACH_SEND_INVALID_MEMORY;
+               return NULL;
+       }
+
+       if (deallocate) {
+               (void) mach_vm_deallocate(map, addr, (mach_vm_size_t)ports_length);
+       }
+
+       objects = (ipc_object_t *) data;
+       dsc->address = data;
+
+       for (i = 0; i < count; i++) {
+               mach_port_name_t name = names[i];
+               ipc_object_t object;
+
+               if (!MACH_PORT_VALID(name)) {
+                       objects[i] = ip_to_object(CAST_MACH_NAME_TO_PORT(name));
+                       continue;
+               }
+
+               kern_return_t kr = ipc_object_copyin(space, name, user_disp, &object, 0, NULL, kmsg->ikm_flags);
+
+               if (kr != KERN_SUCCESS) {
+                       unsigned int j;
+
+                       for (j = 0; j < i; j++) {
+                               object = objects[j];
+                               if (IPC_OBJECT_VALID(object)) {
+                                       ipc_object_destroy(object, result_disp);
+                               }
+                       }
+                       kfree(data, ports_length);
+                       dsc->address = NULL;
+                       if (((*optionp & MACH_SEND_KERNEL) == 0) && (kr == KERN_INVALID_RIGHT)) {
+                               mach_port_guard_exception(name, 0, 0, kGUARD_EXC_SEND_INVALID_RIGHT);
+                       }
+                       *mr = MACH_SEND_INVALID_RIGHT;
+                       return NULL;
+               }
+
+               if ((dsc->disposition == MACH_MSG_TYPE_PORT_RECEIVE) &&
+                   ipc_port_check_circularity(ip_object_to_port(object),
+                   ip_object_to_port(dest))) {
+                       kmsg->ikm_header->msgh_bits |= MACH_MSGH_BITS_CIRCULAR;
+               }
+
+               objects[i] = object;
+       }
+
+       return user_dsc;
+}
+
+static mach_msg_descriptor_t *
+ipc_kmsg_copyin_guarded_port_descriptor(
+       mach_msg_guarded_port_descriptor_t *dsc,
+       mach_msg_descriptor_t *user_addr,
+       int is_64bit,
+       ipc_space_t space,
+       ipc_object_t dest,
+       ipc_kmsg_t kmsg,
+       mach_msg_option_t *optionp,
+       mach_msg_return_t *mr)
+{
+       mach_msg_descriptor_t       *user_dsc;
+       mach_msg_type_name_t        disp;
+       mach_msg_type_name_t        result_disp;
+       mach_port_name_t            name;
+       mach_msg_guard_flags_t      guard_flags;
+       ipc_object_t                object;
+       mach_port_context_t         context;
+
+       if (!is_64bit) {
+               mach_msg_guarded_port_descriptor32_t *user_gp_dsc = (typeof(user_gp_dsc))user_addr;
+               name = user_gp_dsc->name;
+               guard_flags = user_gp_dsc->flags;
+               disp = user_gp_dsc->disposition;
+               context = user_gp_dsc->context;
+               user_dsc = (mach_msg_descriptor_t *)(user_gp_dsc + 1);
+       } else {
+               mach_msg_guarded_port_descriptor64_t *user_gp_dsc = (typeof(user_gp_dsc))user_addr;
+               name = user_gp_dsc->name;
+               guard_flags = user_gp_dsc->flags;
+               disp = user_gp_dsc->disposition;
+               context = user_gp_dsc->context;
+               user_dsc = (mach_msg_descriptor_t *)(user_gp_dsc + 1);
+       }
+
+       guard_flags &= MACH_MSG_GUARD_FLAGS_MASK;
+       result_disp = ipc_object_copyin_type(disp);
+
+       if (MACH_PORT_VALID(name)) {
+               kern_return_t kr = ipc_object_copyin(space, name, disp, &object, context, &guard_flags, kmsg->ikm_flags);
+               if (kr != KERN_SUCCESS) {
+                       if (((*optionp & MACH_SEND_KERNEL) == 0) && (kr == KERN_INVALID_RIGHT)) {
+                               mach_port_guard_exception(name, 0, 0, kGUARD_EXC_SEND_INVALID_RIGHT);
+                       }
+                       *mr = MACH_SEND_INVALID_RIGHT;
+                       return NULL;
+               }
+
+               if ((result_disp == MACH_MSG_TYPE_PORT_RECEIVE) &&
+                   ipc_port_check_circularity(ip_object_to_port(object),
+                   ip_object_to_port(dest))) {
+                       kmsg->ikm_header->msgh_bits |= MACH_MSGH_BITS_CIRCULAR;
+               }
+               dsc->name = ip_object_to_port(object);
+       } else {
+               dsc->name = CAST_MACH_NAME_TO_PORT(name);
+       }
+       dsc->flags = guard_flags;
+       dsc->disposition = result_disp;
+       dsc->type = MACH_MSG_GUARDED_PORT_DESCRIPTOR;
+
+#if __LP64__
+       dsc->pad_end = 0;         // debug, unnecessary
+#endif
+       return user_dsc;
 }
 
+
 /*
  *     Routine:        ipc_kmsg_copyin_body
  *     Purpose:
@@ -2958,143 +3356,186 @@ ipc_kmsg_copyin_ool_ports_descriptor(
  *             MACH_SEND_MSG_TOO_SMALL Body is too small for types/data.
  *             MACH_SEND_INVALID_RT_OOL_SIZE OOL Buffer too large for RT
  *             MACH_MSG_INVALID_RT_DESCRIPTOR Dealloc and RT are incompatible
+ *             MACH_SEND_NO_GRANT_DEST Dest port doesn't accept ports in body
  */
 
 mach_msg_return_t
 ipc_kmsg_copyin_body(
-       ipc_kmsg_t      kmsg,
-       ipc_space_t     space,
-       vm_map_t        map)
+       ipc_kmsg_t      kmsg,
+       ipc_space_t     space,
+       vm_map_t    map,
+       mach_msg_option_t *optionp)
 {
-    ipc_object_t                       dest;
-    mach_msg_body_t            *body;
-    mach_msg_descriptor_t      *daddr, *naddr;
-    mach_msg_descriptor_t      *user_addr, *kern_addr;
-    mach_msg_type_number_t     dsc_count;
-    boolean_t                  is_task_64bit = (map->max_offset > VM_MAX_ADDRESS);
-    boolean_t                  complex = FALSE;
-    vm_size_t                  space_needed = 0;
-    vm_offset_t                        paddr = 0;
-    vm_map_copy_t              copy = VM_MAP_COPY_NULL;
-    mach_msg_type_number_t     i;
-    mach_msg_return_t          mr = MACH_MSG_SUCCESS;
-
-    vm_size_t           descriptor_size = 0;
-
-    mach_msg_type_number_t total_ool_port_count = 0;
-
-    /*
-     * Determine if the target is a kernel port.
-     */
-    dest = (ipc_object_t) kmsg->ikm_header->msgh_remote_port;
-    body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
-    naddr = (mach_msg_descriptor_t *) (body + 1);
-
-    dsc_count = body->msgh_descriptor_count;
-    if (dsc_count == 0)
-       return MACH_MSG_SUCCESS;
-
-    /*
-     * Make an initial pass to determine kernal VM space requirements for
-     * physical copies and possible contraction of the descriptors from
-     * processes with pointers larger than the kernel's.
-     */
-    daddr = NULL;
-    for (i = 0; i < dsc_count; i++) {
-       mach_msg_size_t size;
-       mach_msg_type_number_t ool_port_count = 0;
+       ipc_object_t                dest;
+       mach_msg_body_t             *body;
+       mach_msg_descriptor_t       *daddr, *naddr, *end;
+       mach_msg_descriptor_t       *user_addr, *kern_addr;
+       mach_msg_type_number_t      dsc_count;
+       boolean_t                   is_task_64bit = (map->max_offset > VM_MAX_ADDRESS);
+       boolean_t                   complex = FALSE;
+       boolean_t                   contains_port_desc = FALSE;
+       vm_size_t                   space_needed = 0;
+       vm_offset_t                 paddr = 0;
+       vm_map_copy_t               copy = VM_MAP_COPY_NULL;
+       mach_msg_type_number_t      i;
+       mach_msg_return_t           mr = MACH_MSG_SUCCESS;
+       ipc_port_t                  remote_port = kmsg->ikm_header->msgh_remote_port;
+
+       vm_size_t           descriptor_size = 0;
+
+       mach_msg_type_number_t total_ool_port_count = 0;
+       mach_msg_guard_flags_t guard_flags = 0;
+       mach_port_context_t context;
+       mach_msg_type_name_t disp;
 
-       daddr = naddr;
-
-       /* make sure the descriptor fits in the message */
-       if (is_task_64bit) {
-           switch (daddr->type.type) {
-           case MACH_MSG_OOL_DESCRIPTOR:
-           case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
-           case MACH_MSG_OOL_PORTS_DESCRIPTOR:
-                   descriptor_size += 16;
-            naddr = (typeof(naddr))((vm_offset_t)daddr + 16);
-            break;
-           default:
-                   descriptor_size += 12;
-            naddr = (typeof(naddr))((vm_offset_t)daddr + 12);
-            break;
-           }
-       } else {
-        descriptor_size += 12;
-        naddr = (typeof(naddr))((vm_offset_t)daddr + 12);
-       }
+       /*
+        * Determine if the target is a kernel port.
+        */
+       dest = ip_to_object(remote_port);
+       body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
+       naddr = (mach_msg_descriptor_t *) (body + 1);
+       end = (mach_msg_descriptor_t *) ((vm_offset_t)kmsg->ikm_header + kmsg->ikm_header->msgh_size);
 
-       if (naddr > (mach_msg_descriptor_t *)
-           ((vm_offset_t)kmsg->ikm_header + kmsg->ikm_header->msgh_size)) {
-               mr = MACH_SEND_MSG_TOO_SMALL;
-               goto clean_message;
+       dsc_count = body->msgh_descriptor_count;
+       if (dsc_count == 0) {
+               return MACH_MSG_SUCCESS;
        }
 
-       switch (daddr->type.type) {
-       case MACH_MSG_OOL_DESCRIPTOR:
-       case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
-        size = (is_task_64bit) ?
-               ((mach_msg_ool_descriptor64_t *)daddr)->size :
-           daddr->out_of_line.size;
-
-           if (daddr->out_of_line.copy != MACH_MSG_PHYSICAL_COPY &&
-               daddr->out_of_line.copy != MACH_MSG_VIRTUAL_COPY) {
-               /*
-                * Invalid copy option
-                */
-               mr = MACH_SEND_INVALID_TYPE;
-               goto clean_message;
-           }
-
-           if ((size >= MSG_OOL_SIZE_SMALL) &&
-               (daddr->out_of_line.copy == MACH_MSG_PHYSICAL_COPY) &&
-               !(daddr->out_of_line.deallocate)) {
+       /*
+        * Make an initial pass to determine kernal VM space requirements for
+        * physical copies and possible contraction of the descriptors from
+        * processes with pointers larger than the kernel's.
+        */
+       daddr = NULL;
+       for (i = 0; i < dsc_count; i++) {
+               mach_msg_size_t size;
+               mach_msg_type_number_t ool_port_count = 0;
+
+               daddr = naddr;
+
+               /* make sure the descriptor fits in the message */
+               if (is_task_64bit) {
+                       if ((mach_msg_descriptor_t*)((vm_offset_t)daddr + 12) > end) {
+                               mr = MACH_SEND_MSG_TOO_SMALL;
+                               goto clean_message;
+                       }
 
-               /*
-                * Out-of-line memory descriptor, accumulate kernel
-                * memory requirements
-                */
-               if (space_needed + round_page(size) <= space_needed) {
-                       /* Overflow dectected */
-                       mr = MACH_MSG_VM_KERNEL;
-                       goto clean_message;
+                       switch (daddr->type.type) {
+                       case MACH_MSG_OOL_DESCRIPTOR:
+                       case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
+                       case MACH_MSG_OOL_PORTS_DESCRIPTOR:
+                       case MACH_MSG_GUARDED_PORT_DESCRIPTOR:
+                               descriptor_size += 16;
+                               naddr = (typeof(naddr))((vm_offset_t)daddr + 16);
+                               break;
+                       default:
+                               descriptor_size += 12;
+                               naddr = (typeof(naddr))((vm_offset_t)daddr + 12);
+                               break;
+                       }
+               } else {
+                       descriptor_size += 12;
+                       naddr = (typeof(naddr))((vm_offset_t)daddr + 12);
                }
 
-               space_needed += round_page(size);
-               if (space_needed > ipc_kmsg_max_vm_space) {
-                   /* Per message kernel memory limit exceeded */
-                   mr = MACH_MSG_VM_KERNEL;
-                   goto clean_message;
-               }
-           }
-           break;
-       case MACH_MSG_PORT_DESCRIPTOR:
-               if (os_add_overflow(total_ool_port_count, 1, &total_ool_port_count)) {
-                       /* Overflow detected */
-                       mr = MACH_SEND_TOO_LARGE;
-                       goto clean_message;
-               }
-               break;
-       case MACH_MSG_OOL_PORTS_DESCRIPTOR:
-               ool_port_count = (is_task_64bit) ?
-                       ((mach_msg_ool_ports_descriptor64_t *)daddr)->count :
-                       daddr->ool_ports.count;
-
-               if (os_add_overflow(total_ool_port_count, ool_port_count, &total_ool_port_count)) {
-                       /* Overflow detected */
-                       mr = MACH_SEND_TOO_LARGE;
+               if (naddr > end) {
+                       mr = MACH_SEND_MSG_TOO_SMALL;
                        goto clean_message;
                }
 
-               if (ool_port_count > (ipc_kmsg_max_vm_space/sizeof(mach_port_t))) {
-                       /* Per message kernel memory limit exceeded */
-                       mr = MACH_SEND_TOO_LARGE;
-                       goto clean_message;
+               switch (daddr->type.type) {
+               case MACH_MSG_OOL_DESCRIPTOR:
+               case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
+                       size = (is_task_64bit) ?
+                           ((mach_msg_ool_descriptor64_t *)daddr)->size :
+                           daddr->out_of_line.size;
+
+                       if (daddr->out_of_line.copy != MACH_MSG_PHYSICAL_COPY &&
+                           daddr->out_of_line.copy != MACH_MSG_VIRTUAL_COPY) {
+                               /*
+                                * Invalid copy option
+                                */
+                               mr = MACH_SEND_INVALID_TYPE;
+                               goto clean_message;
+                       }
+
+                       if ((size >= MSG_OOL_SIZE_SMALL) &&
+                           (daddr->out_of_line.copy == MACH_MSG_PHYSICAL_COPY) &&
+                           !(daddr->out_of_line.deallocate)) {
+                               /*
+                                * Out-of-line memory descriptor, accumulate kernel
+                                * memory requirements
+                                */
+                               if (space_needed + round_page(size) <= space_needed) {
+                                       /* Overflow dectected */
+                                       mr = MACH_MSG_VM_KERNEL;
+                                       goto clean_message;
+                               }
+
+                               space_needed += round_page(size);
+                               if (space_needed > ipc_kmsg_max_vm_space) {
+                                       /* Per message kernel memory limit exceeded */
+                                       mr = MACH_MSG_VM_KERNEL;
+                                       goto clean_message;
+                               }
+                       }
+                       break;
+               case MACH_MSG_PORT_DESCRIPTOR:
+                       if (os_add_overflow(total_ool_port_count, 1, &total_ool_port_count)) {
+                               /* Overflow detected */
+                               mr = MACH_SEND_TOO_LARGE;
+                               goto clean_message;
+                       }
+                       contains_port_desc = TRUE;
+                       break;
+               case MACH_MSG_OOL_PORTS_DESCRIPTOR:
+                       ool_port_count = (is_task_64bit) ?
+                           ((mach_msg_ool_ports_descriptor64_t *)daddr)->count :
+                           daddr->ool_ports.count;
+
+                       if (os_add_overflow(total_ool_port_count, ool_port_count, &total_ool_port_count)) {
+                               /* Overflow detected */
+                               mr = MACH_SEND_TOO_LARGE;
+                               goto clean_message;
+                       }
+
+                       if (ool_port_count > (ipc_kmsg_max_vm_space / sizeof(mach_port_t))) {
+                               /* Per message kernel memory limit exceeded */
+                               mr = MACH_SEND_TOO_LARGE;
+                               goto clean_message;
+                       }
+                       contains_port_desc = TRUE;
+                       break;
+               case MACH_MSG_GUARDED_PORT_DESCRIPTOR:
+                       guard_flags = (is_task_64bit) ?
+                           ((mach_msg_guarded_port_descriptor64_t *)daddr)->flags :
+                           ((mach_msg_guarded_port_descriptor32_t *)daddr)->flags;
+                       context = (is_task_64bit) ?
+                           ((mach_msg_guarded_port_descriptor64_t *)daddr)->context :
+                           ((mach_msg_guarded_port_descriptor32_t *)daddr)->context;
+                       disp = (is_task_64bit) ?
+                           ((mach_msg_guarded_port_descriptor64_t *)daddr)->disposition :
+                           ((mach_msg_guarded_port_descriptor32_t *)daddr)->disposition;
+
+                       /* Only MACH_MSG_TYPE_MOVE_RECEIVE is supported for now */
+                       if (!guard_flags || ((guard_flags & ~MACH_MSG_GUARD_FLAGS_MASK) != 0) ||
+                           ((guard_flags & MACH_MSG_GUARD_FLAGS_UNGUARDED_ON_SEND) && (context != 0)) ||
+                           (disp != MACH_MSG_TYPE_MOVE_RECEIVE)) {
+                               /*
+                                * Invalid guard flags, context or disposition
+                                */
+                               mr = MACH_SEND_INVALID_TYPE;
+                               goto clean_message;
+                       }
+                       if (os_add_overflow(total_ool_port_count, 1, &total_ool_port_count)) {
+                               /* Overflow detected */
+                               mr = MACH_SEND_TOO_LARGE;
+                               goto clean_message;
+                       }
+                       contains_port_desc = TRUE;
+                       break;
                }
-               break;
        }
-    }
 
        /* Sending more than 16383 rights in one message seems crazy */
        if (total_ool_port_count >= (MACH_PORT_UREFS_MAX / 4)) {
@@ -3102,79 +3543,96 @@ ipc_kmsg_copyin_body(
                goto clean_message;
        }
 
-    /*
-     * Allocate space in the pageable kernel ipc copy map for all the
-     * ool data that is to be physically copied.  Map is marked wait for
-     * space.
-     */
-    if (space_needed) {
-        if (vm_allocate_kernel(ipc_kernel_copy_map, &paddr, space_needed,
-                    VM_FLAGS_ANYWHERE, VM_KERN_MEMORY_IPC) != KERN_SUCCESS) {
-            mr = MACH_MSG_VM_KERNEL;
-            goto clean_message;
-        }
-    }
-
-    /* user_addr = just after base as it was copied in */
-    user_addr = (mach_msg_descriptor_t *)((vm_offset_t)kmsg->ikm_header + sizeof(mach_msg_base_t));
-
-    /* Shift the mach_msg_base_t down to make room for dsc_count*16bytes of descriptors */
-    if(descriptor_size != 16*dsc_count) {
-        vm_offset_t dsc_adjust = 16*dsc_count - descriptor_size;
-
-        memmove((char *)(((vm_offset_t)kmsg->ikm_header) - dsc_adjust), kmsg->ikm_header, sizeof(mach_msg_base_t));
-        kmsg->ikm_header = (mach_msg_header_t *)((vm_offset_t)kmsg->ikm_header - dsc_adjust);
-
-        /* Update the message size for the larger in-kernel representation */
-        kmsg->ikm_header->msgh_size += (mach_msg_size_t)dsc_adjust;
-    }
-
-
-    /* kern_addr = just after base after it has been (conditionally) moved */
-    kern_addr = (mach_msg_descriptor_t *)((vm_offset_t)kmsg->ikm_header + sizeof(mach_msg_base_t));
-
-    /* handle the OOL regions and port descriptors. */
-    for(i=0;i<dsc_count;i++) {
-        switch (user_addr->type.type) {
-            case MACH_MSG_PORT_DESCRIPTOR:
-                user_addr = ipc_kmsg_copyin_port_descriptor((mach_msg_port_descriptor_t *)kern_addr, 
-                        (mach_msg_legacy_port_descriptor_t *)user_addr, space, dest, kmsg, &mr);
-                kern_addr++;
-                complex = TRUE;
-                break;
-            case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
-            case MACH_MSG_OOL_DESCRIPTOR: 
-                user_addr = ipc_kmsg_copyin_ool_descriptor((mach_msg_ool_descriptor_t *)kern_addr, 
-                        user_addr, is_task_64bit, &paddr, &copy, &space_needed, map, &mr);
-                kern_addr++;
-                complex = TRUE;
-                break;
-            case MACH_MSG_OOL_PORTS_DESCRIPTOR: 
-                user_addr = ipc_kmsg_copyin_ool_ports_descriptor((mach_msg_ool_ports_descriptor_t *)kern_addr, 
-                        user_addr, is_task_64bit, map, space, dest, kmsg, &mr);
-                kern_addr++;
-                complex = TRUE;
-                break;
-            default:
-                /* Invalid descriptor */
-                mr = MACH_SEND_INVALID_TYPE;
-                break;
-        }
-
-        if (MACH_MSG_SUCCESS != mr) {
-            /* clean from start of message descriptors to i */
-            ipc_kmsg_clean_partial(kmsg, i,
-                    (mach_msg_descriptor_t *)((mach_msg_base_t *)kmsg->ikm_header + 1),
-                    paddr, space_needed);
-            goto out;
-        }
-    } /* End of loop */ 
-    
-    if (!complex) {
-       kmsg->ikm_header->msgh_bits &= ~MACH_MSGH_BITS_COMPLEX;
-    }
- out:
-    return mr;
+       /*
+        * Check if dest is a no-grant port; Since this bit is set only on
+        * port construction and cannot be unset later, we can peek at the
+        * bit without paying the cost of locking the port.
+        */
+       if (contains_port_desc && remote_port->ip_no_grant) {
+               mr = MACH_SEND_NO_GRANT_DEST;
+               goto clean_message;
+       }
+
+       /*
+        * Allocate space in the pageable kernel ipc copy map for all the
+        * ool data that is to be physically copied.  Map is marked wait for
+        * space.
+        */
+       if (space_needed) {
+               if (vm_allocate_kernel(ipc_kernel_copy_map, &paddr, space_needed,
+                   VM_FLAGS_ANYWHERE, VM_KERN_MEMORY_IPC) != KERN_SUCCESS) {
+                       mr = MACH_MSG_VM_KERNEL;
+                       goto clean_message;
+               }
+       }
+
+       /* user_addr = just after base as it was copied in */
+       user_addr = (mach_msg_descriptor_t *)((vm_offset_t)kmsg->ikm_header + sizeof(mach_msg_base_t));
+
+       /* Shift the mach_msg_base_t down to make room for dsc_count*16bytes of descriptors on 64 bit kernels
+        */
+       if (descriptor_size != 16 * dsc_count) {
+               vm_offset_t dsc_adjust = 16 * dsc_count - descriptor_size;
+
+               memmove((char *)(((vm_offset_t)kmsg->ikm_header) - dsc_adjust), kmsg->ikm_header, sizeof(mach_msg_base_t));
+               kmsg->ikm_header = (mach_msg_header_t *)((vm_offset_t)kmsg->ikm_header - dsc_adjust);
+
+               /* Update the message size for the larger in-kernel representation */
+               kmsg->ikm_header->msgh_size += (mach_msg_size_t)dsc_adjust;
+       }
+
+
+       /* kern_addr = just after base after it has been (conditionally) moved */
+       kern_addr = (mach_msg_descriptor_t *)((vm_offset_t)kmsg->ikm_header + sizeof(mach_msg_base_t));
+
+       /* handle the OOL regions and port descriptors. */
+       for (i = 0; i < dsc_count; i++) {
+               switch (user_addr->type.type) {
+               case MACH_MSG_PORT_DESCRIPTOR:
+                       user_addr = ipc_kmsg_copyin_port_descriptor((mach_msg_port_descriptor_t *)kern_addr,
+                           (mach_msg_legacy_port_descriptor_t *)user_addr, space, dest, kmsg, optionp, &mr);
+                       kern_addr++;
+                       complex = TRUE;
+                       break;
+               case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
+               case MACH_MSG_OOL_DESCRIPTOR:
+                       user_addr = ipc_kmsg_copyin_ool_descriptor((mach_msg_ool_descriptor_t *)kern_addr,
+                           user_addr, is_task_64bit, &paddr, &copy, &space_needed, map, optionp, &mr);
+                       kern_addr++;
+                       complex = TRUE;
+                       break;
+               case MACH_MSG_OOL_PORTS_DESCRIPTOR:
+                       user_addr = ipc_kmsg_copyin_ool_ports_descriptor((mach_msg_ool_ports_descriptor_t *)kern_addr,
+                           user_addr, is_task_64bit, map, space, dest, kmsg, optionp, &mr);
+                       kern_addr++;
+                       complex = TRUE;
+                       break;
+               case MACH_MSG_GUARDED_PORT_DESCRIPTOR:
+                       user_addr = ipc_kmsg_copyin_guarded_port_descriptor((mach_msg_guarded_port_descriptor_t *)kern_addr,
+                           user_addr, is_task_64bit, space, dest, kmsg, optionp, &mr);
+                       kern_addr++;
+                       complex = TRUE;
+                       break;
+               default:
+                       /* Invalid descriptor */
+                       mr = MACH_SEND_INVALID_TYPE;
+                       break;
+               }
+
+               if (MACH_MSG_SUCCESS != mr) {
+                       /* clean from start of message descriptors to i */
+                       ipc_kmsg_clean_partial(kmsg, i,
+                           (mach_msg_descriptor_t *)((mach_msg_base_t *)kmsg->ikm_header + 1),
+                           paddr, space_needed);
+                       goto out;
+               }
+       }         /* End of loop */
+
+       if (!complex) {
+               kmsg->ikm_header->msgh_bits &= ~MACH_MSGH_BITS_COMPLEX;
+       }
+out:
+       return mr;
 
 clean_message:
        /* no descriptors have been copied in yet */
@@ -3209,50 +3667,49 @@ clean_message:
 
 mach_msg_return_t
 ipc_kmsg_copyin(
-       ipc_kmsg_t              kmsg,
-       ipc_space_t             space,
-       vm_map_t                map,
+       ipc_kmsg_t              kmsg,
+       ipc_space_t             space,
+       vm_map_t                map,
        mach_msg_priority_t override,
-       mach_msg_option_t       *optionp)
+       mach_msg_option_t       *optionp)
 {
-    mach_msg_return_t          mr;
+       mach_msg_return_t           mr;
 
-    kmsg->ikm_header->msgh_bits &= MACH_MSGH_BITS_USER;
+       kmsg->ikm_header->msgh_bits &= MACH_MSGH_BITS_USER;
 
-    mr = ipc_kmsg_copyin_header(kmsg, space, override, optionp);
+       mr = ipc_kmsg_copyin_header(kmsg, space, override, optionp);
 
-    if (mr != MACH_MSG_SUCCESS)
-       return mr;
+       if (mr != MACH_MSG_SUCCESS) {
+               return mr;
+       }
 
-    KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_IPC,MACH_IPC_MSG_SEND) | DBG_FUNC_NONE,
-                         VM_KERNEL_ADDRPERM((uintptr_t)kmsg),
-                         (uintptr_t)kmsg->ikm_header->msgh_bits,
-                         (uintptr_t)kmsg->ikm_header->msgh_id,
-                         VM_KERNEL_ADDRPERM((uintptr_t)unsafe_convert_port_to_voucher(kmsg->ikm_voucher)),
-                         0);
-
-    DEBUG_KPRINT_SYSCALL_IPC("ipc_kmsg_copyin header:\n%.8x\n%.8x\n%p\n%p\n%p\n%.8x\n",
-                            kmsg->ikm_header->msgh_size,
-                            kmsg->ikm_header->msgh_bits,
-                            kmsg->ikm_header->msgh_remote_port,
-                            kmsg->ikm_header->msgh_local_port,
-                            kmsg->ikm_voucher,
-                            kmsg->ikm_header->msgh_id);
-
-    if ((kmsg->ikm_header->msgh_bits & MACH_MSGH_BITS_COMPLEX) == 0)
-       return MACH_MSG_SUCCESS;
-    
-       mr = ipc_kmsg_copyin_body( kmsg, space, map);
+       KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_IPC, MACH_IPC_MSG_SEND) | DBG_FUNC_NONE,
+           VM_KERNEL_ADDRPERM((uintptr_t)kmsg),
+           (uintptr_t)kmsg->ikm_header->msgh_bits,
+           (uintptr_t)kmsg->ikm_header->msgh_id,
+           VM_KERNEL_ADDRPERM((uintptr_t)unsafe_convert_port_to_voucher(kmsg->ikm_voucher)),
+           0);
+
+       DEBUG_KPRINT_SYSCALL_IPC("ipc_kmsg_copyin header:\n%.8x\n%.8x\n%p\n%p\n%p\n%.8x\n",
+           kmsg->ikm_header->msgh_size,
+           kmsg->ikm_header->msgh_bits,
+           kmsg->ikm_header->msgh_remote_port,
+           kmsg->ikm_header->msgh_local_port,
+           kmsg->ikm_voucher,
+           kmsg->ikm_header->msgh_id);
+
+       if ((kmsg->ikm_header->msgh_bits & MACH_MSGH_BITS_COMPLEX) == 0) {
+               return MACH_MSG_SUCCESS;
+       }
 
+       mr = ipc_kmsg_copyin_body( kmsg, space, map, optionp);
        /* unreachable if !DEBUG */
        __unreachable_ok_push
-       if (DEBUG_KPRINT_SYSCALL_PREDICATE(DEBUG_KPRINT_SYSCALL_IPC_MASK))
-       {
+       if (DEBUG_KPRINT_SYSCALL_PREDICATE(DEBUG_KPRINT_SYSCALL_IPC_MASK)) {
                kprintf("body:\n");
                uint32_t i;
-               for(i=0;i*4 < (kmsg->ikm_header->msgh_size - sizeof(mach_msg_header_t));i++)
-               {
-                       kprintf("%.4x\n",((uint32_t *)(kmsg->ikm_header + 1))[i]);
+               for (i = 0; i * 4 < (kmsg->ikm_header->msgh_size - sizeof(mach_msg_header_t)); i++) {
+                       kprintf("%.4x\n", ((uint32_t *)(kmsg->ikm_header + 1))[i]);
                }
        }
        __unreachable_ok_pop
@@ -3275,21 +3732,24 @@ ipc_kmsg_copyin(
 
 mach_msg_return_t
 ipc_kmsg_copyin_from_kernel(
-       ipc_kmsg_t      kmsg)
+       ipc_kmsg_t      kmsg)
 {
        mach_msg_bits_t bits = kmsg->ikm_header->msgh_bits;
        mach_msg_type_name_t rname = MACH_MSGH_BITS_REMOTE(bits);
        mach_msg_type_name_t lname = MACH_MSGH_BITS_LOCAL(bits);
-       ipc_object_t remote = (ipc_object_t) kmsg->ikm_header->msgh_remote_port;
-       ipc_object_t local = (ipc_object_t) kmsg->ikm_header->msgh_local_port;
+       ipc_object_t remote = ip_to_object(kmsg->ikm_header->msgh_remote_port);
+       ipc_object_t local = ip_to_object(kmsg->ikm_header->msgh_local_port);
+       ipc_port_t dest = kmsg->ikm_header->msgh_remote_port;
 
        /* translate the destination and reply ports */
-       if (!IO_VALID(remote))
+       if (!IO_VALID(remote)) {
                return MACH_SEND_INVALID_DEST;
+       }
 
        ipc_object_copyin_from_kernel(remote, rname);
-       if (IO_VALID(local))
+       if (IO_VALID(local)) {
                ipc_object_copyin_from_kernel(local, lname);
+       }
 
        /*
         *      The common case is a complex message with no reply port,
@@ -3297,133 +3757,188 @@ ipc_kmsg_copyin_from_kernel(
         */
 
        if (bits == (MACH_MSGH_BITS_COMPLEX |
-                    MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND, 0))) {
+           MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND, 0))) {
                bits = (MACH_MSGH_BITS_COMPLEX |
-                       MACH_MSGH_BITS(MACH_MSG_TYPE_PORT_SEND, 0));
+                   MACH_MSGH_BITS(MACH_MSG_TYPE_PORT_SEND, 0));
 
                kmsg->ikm_header->msgh_bits = bits;
        } else {
                bits = (MACH_MSGH_BITS_OTHER(bits) |
-                       MACH_MSGH_BITS(ipc_object_copyin_type(rname),
-                                      ipc_object_copyin_type(lname)));
+                   MACH_MSGH_BITS(ipc_object_copyin_type(rname),
+                   ipc_object_copyin_type(lname)));
 
                kmsg->ikm_header->msgh_bits = bits;
-               if ((bits & MACH_MSGH_BITS_COMPLEX) == 0)
+               if ((bits & MACH_MSGH_BITS_COMPLEX) == 0) {
                        return MACH_MSG_SUCCESS;
+               }
        }
-    {
-       mach_msg_descriptor_t   *saddr;
-       mach_msg_body_t         *body;
-       mach_msg_type_number_t  i, count;
-
-       body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
-       saddr = (mach_msg_descriptor_t *) (body + 1);
-       count = body->msgh_descriptor_count;
-
-       for (i = 0; i < count; i++, saddr++) {
-
-           switch (saddr->type.type) {
-           
-               case MACH_MSG_PORT_DESCRIPTOR: {
-                   mach_msg_type_name_t        name;
-                   ipc_object_t                object;
-                   mach_msg_port_descriptor_t  *dsc;
-               
-                   dsc = &saddr->port;
-               
-                   /* this is really the type SEND, SEND_ONCE, etc. */
-                   name = dsc->disposition;
-                   object = (ipc_object_t) dsc->name;
-                   dsc->disposition = ipc_object_copyin_type(name);
-               
-                   if (!IO_VALID(object)) {
-                       break;
-                   }
-
-                   ipc_object_copyin_from_kernel(object, name);
-                   
-                   /* CDY avoid circularity when the destination is also */
-                   /* the kernel.  This check should be changed into an  */
-                   /* assert when the new kobject model is in place since*/
-                   /* ports will not be used in kernel to kernel chats   */
-                       
-                   if (((ipc_port_t)remote)->ip_receiver != ipc_space_kernel) {
-                      if ((dsc->disposition == MACH_MSG_TYPE_PORT_RECEIVE) &&
-                          ipc_port_check_circularity((ipc_port_t) object, 
-                                               (ipc_port_t) remote)) {
-                          kmsg->ikm_header->msgh_bits |= 
-                                       MACH_MSGH_BITS_CIRCULAR;
-                      }
-                   }
-                   break;
-               }
-               case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
-               case MACH_MSG_OOL_DESCRIPTOR: {
-                   /*
-                    * The sender should supply ready-made memory, i.e.
-                    * a vm_map_copy_t, so we don't need to do anything.
-                    */
-                   break;
-               }
-               case MACH_MSG_OOL_PORTS_DESCRIPTOR: {
-                   ipc_object_t                        *objects;
-                   unsigned int                        j;
-                   mach_msg_type_name_t                name;
-                   mach_msg_ool_ports_descriptor_t     *dsc;
-               
-                   dsc = (mach_msg_ool_ports_descriptor_t *)&saddr->ool_ports;
-
-                   /* this is really the type SEND, SEND_ONCE, etc. */
-                   name = dsc->disposition;
-                   dsc->disposition = ipc_object_copyin_type(name);
-               
-                   objects = (ipc_object_t *) dsc->address;
-               
-                   for ( j = 0; j < dsc->count; j++) {
-                       ipc_object_t object = objects[j];
-                       
-                       if (!IO_VALID(object))
-                           continue;
-                       
-                       ipc_object_copyin_from_kernel(object, name);
-    
-                       if ((dsc->disposition == MACH_MSG_TYPE_PORT_RECEIVE) &&
-                           ipc_port_check_circularity(
-                                                      (ipc_port_t) object,
-                                                      (ipc_port_t) remote))
-                           kmsg->ikm_header->msgh_bits |= MACH_MSGH_BITS_CIRCULAR;
-                   }
-                   break;
-               }
-               default: {
-#if    MACH_ASSERT
-                   panic("ipc_kmsg_copyin_from_kernel:  bad descriptor");
-#endif /* MACH_ASSERT */
+
+       /*
+        * Check if the remote port accepts ports in the body.
+        */
+       if (dest->ip_no_grant) {
+               mach_msg_descriptor_t   *saddr;
+               mach_msg_body_t         *body;
+               mach_msg_type_number_t  i, count;
+
+               body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
+               saddr = (mach_msg_descriptor_t *) (body + 1);
+               count = body->msgh_descriptor_count;
+
+               for (i = 0; i < count; i++, saddr++) {
+                       switch (saddr->type.type) {
+                       case MACH_MSG_PORT_DESCRIPTOR:
+                       case MACH_MSG_OOL_PORTS_DESCRIPTOR:
+                       case MACH_MSG_GUARDED_PORT_DESCRIPTOR:
+                               /* no descriptors have been copied in yet */
+                               ipc_kmsg_clean_partial(kmsg, 0, NULL, 0, 0);
+                               return MACH_SEND_NO_GRANT_DEST;
+                       }
                }
-           }
        }
-    }
-    return MACH_MSG_SUCCESS;
+       {
+               mach_msg_descriptor_t   *saddr;
+               mach_msg_body_t         *body;
+               mach_msg_type_number_t  i, count;
+
+               body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
+               saddr = (mach_msg_descriptor_t *) (body + 1);
+               count = body->msgh_descriptor_count;
+
+               for (i = 0; i < count; i++, saddr++) {
+                       switch (saddr->type.type) {
+                       case MACH_MSG_PORT_DESCRIPTOR: {
+                               mach_msg_type_name_t        name;
+                               ipc_object_t                object;
+                               mach_msg_port_descriptor_t  *dsc;
+
+                               dsc = &saddr->port;
+
+                               /* this is really the type SEND, SEND_ONCE, etc. */
+                               name = dsc->disposition;
+                               object = ip_to_object(dsc->name);
+                               dsc->disposition = ipc_object_copyin_type(name);
+
+                               if (!IO_VALID(object)) {
+                                       break;
+                               }
+
+                               ipc_object_copyin_from_kernel(object, name);
+
+                               /* CDY avoid circularity when the destination is also */
+                               /* the kernel.  This check should be changed into an  */
+                               /* assert when the new kobject model is in place since*/
+                               /* ports will not be used in kernel to kernel chats   */
+
+                               if (ip_object_to_port(remote)->ip_receiver != ipc_space_kernel) {
+                                       if ((dsc->disposition == MACH_MSG_TYPE_PORT_RECEIVE) &&
+                                           ipc_port_check_circularity(ip_object_to_port(object),
+                                           ip_object_to_port(remote))) {
+                                               kmsg->ikm_header->msgh_bits |=
+                                                   MACH_MSGH_BITS_CIRCULAR;
+                                       }
+                               }
+                               break;
+                       }
+                       case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
+                       case MACH_MSG_OOL_DESCRIPTOR: {
+                               /*
+                                * The sender should supply ready-made memory, i.e.
+                                * a vm_map_copy_t, so we don't need to do anything.
+                                */
+                               break;
+                       }
+                       case MACH_MSG_OOL_PORTS_DESCRIPTOR: {
+                               ipc_object_t                        *objects;
+                               unsigned int                        j;
+                               mach_msg_type_name_t                name;
+                               mach_msg_ool_ports_descriptor_t     *dsc;
+
+                               dsc = (mach_msg_ool_ports_descriptor_t *)&saddr->ool_ports;
+
+                               /* this is really the type SEND, SEND_ONCE, etc. */
+                               name = dsc->disposition;
+                               dsc->disposition = ipc_object_copyin_type(name);
+
+                               objects = (ipc_object_t *) dsc->address;
+
+                               for (j = 0; j < dsc->count; j++) {
+                                       ipc_object_t object = objects[j];
+
+                                       if (!IO_VALID(object)) {
+                                               continue;
+                                       }
+
+                                       ipc_object_copyin_from_kernel(object, name);
+
+                                       if ((dsc->disposition == MACH_MSG_TYPE_PORT_RECEIVE) &&
+                                           ipc_port_check_circularity(ip_object_to_port(object),
+                                           ip_object_to_port(remote))) {
+                                               kmsg->ikm_header->msgh_bits |= MACH_MSGH_BITS_CIRCULAR;
+                                       }
+                               }
+                               break;
+                       }
+                       case MACH_MSG_GUARDED_PORT_DESCRIPTOR: {
+                               mach_msg_guarded_port_descriptor_t *dsc = (typeof(dsc)) & saddr->guarded_port;
+                               mach_msg_type_name_t disp = dsc->disposition;
+                               ipc_object_t object = ip_to_object(dsc->name);
+                               dsc->disposition = ipc_object_copyin_type(disp);
+                               assert(dsc->flags == 0);
+
+                               if (!IO_VALID(object)) {
+                                       break;
+                               }
+
+                               ipc_object_copyin_from_kernel(object, disp);
+                               /*
+                                * avoid circularity when the destination is also
+                                * the kernel.  This check should be changed into an
+                                * assert when the new kobject model is in place since
+                                * ports will not be used in kernel to kernel chats
+                                */
+
+                               if (ip_object_to_port(remote)->ip_receiver != ipc_space_kernel) {
+                                       if ((dsc->disposition == MACH_MSG_TYPE_PORT_RECEIVE) &&
+                                           ipc_port_check_circularity(ip_object_to_port(object),
+                                           ip_object_to_port(remote))) {
+                                               kmsg->ikm_header->msgh_bits |= MACH_MSGH_BITS_CIRCULAR;
+                                       }
+                               }
+                               break;
+                       }
+                       default: {
+#if     MACH_ASSERT
+                               panic("ipc_kmsg_copyin_from_kernel:  bad descriptor");
+#endif  /* MACH_ASSERT */
+                       }
+                       }
+               }
+       }
+       return MACH_MSG_SUCCESS;
 }
 
 #if IKM_SUPPORT_LEGACY
 mach_msg_return_t
 ipc_kmsg_copyin_from_kernel_legacy(
-       ipc_kmsg_t      kmsg)
+       ipc_kmsg_t      kmsg)
 {
        mach_msg_bits_t bits = kmsg->ikm_header->msgh_bits;
        mach_msg_type_name_t rname = MACH_MSGH_BITS_REMOTE(bits);
        mach_msg_type_name_t lname = MACH_MSGH_BITS_LOCAL(bits);
-       ipc_object_t remote = (ipc_object_t) kmsg->ikm_header->msgh_remote_port;
-       ipc_object_t local = (ipc_object_t) kmsg->ikm_header->msgh_local_port;
+       ipc_object_t remote = ip_to_object(kmsg->ikm_header->msgh_remote_port);
+       ipc_object_t local = ip_to_object(kmsg->ikm_header->msgh_local_port);
+       ipc_port_t dest = kmsg->ikm_header->msgh_remote_port;
 
        /* translate the destination and reply ports */
-       if (!IO_VALID(remote))
+       if (!IO_VALID(remote)) {
                return MACH_SEND_INVALID_DEST;
+       }
 
        ipc_object_copyin_from_kernel(remote, rname);
-       if (IO_VALID(local))
+       if (IO_VALID(local)) {
                ipc_object_copyin_from_kernel(local, lname);
+       }
 
        /*
         *      The common case is a complex message with no reply port,
@@ -3431,152 +3946,215 @@ ipc_kmsg_copyin_from_kernel_legacy(
         */
 
        if (bits == (MACH_MSGH_BITS_COMPLEX |
-                    MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND, 0))) {
+           MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND, 0))) {
                bits = (MACH_MSGH_BITS_COMPLEX |
-                       MACH_MSGH_BITS(MACH_MSG_TYPE_PORT_SEND, 0));
+                   MACH_MSGH_BITS(MACH_MSG_TYPE_PORT_SEND, 0));
 
                kmsg->ikm_header->msgh_bits = bits;
        } else {
                bits = (MACH_MSGH_BITS_OTHER(bits) |
-                       MACH_MSGH_BITS(ipc_object_copyin_type(rname),
-                                      ipc_object_copyin_type(lname)));
+                   MACH_MSGH_BITS(ipc_object_copyin_type(rname),
+                   ipc_object_copyin_type(lname)));
 
                kmsg->ikm_header->msgh_bits = bits;
-               if ((bits & MACH_MSGH_BITS_COMPLEX) == 0)
+               if ((bits & MACH_MSGH_BITS_COMPLEX) == 0) {
                        return MACH_MSG_SUCCESS;
+               }
        }
-    {
-       mach_msg_legacy_descriptor_t    *saddr;
-        mach_msg_descriptor_t  *daddr;
-       mach_msg_body_t         *body;
-       mach_msg_type_number_t  i, count;
-
-       body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
-       saddr = (typeof(saddr)) (body + 1);
-       count = body->msgh_descriptor_count;
-
-    if(count) {
-        vm_offset_t dsc_adjust = 4*count;
-        memmove((char *)(((vm_offset_t)kmsg->ikm_header) - dsc_adjust), kmsg->ikm_header, sizeof(mach_msg_base_t));
-        kmsg->ikm_header = (mach_msg_header_t *)((vm_offset_t)kmsg->ikm_header - dsc_adjust);
-        /* Update the message size for the larger in-kernel representation */
-        kmsg->ikm_header->msgh_size += dsc_adjust;
-    }
-    daddr = (mach_msg_descriptor_t *)((vm_offset_t)kmsg->ikm_header + sizeof(mach_msg_base_t));
-
-       for (i = 0; i < count; i++, saddr++, daddr++) {
-           switch (saddr->type.type) {
-           
-               case MACH_MSG_PORT_DESCRIPTOR: {
-                   mach_msg_type_name_t        name;
-                   ipc_object_t                object;
-                   mach_msg_legacy_port_descriptor_t   *dsc;
-                   mach_msg_port_descriptor_t  *dest_dsc;
-               
-                   dsc = (typeof(dsc))&saddr->port;
-            dest_dsc = &daddr->port;
-               
-                   /* this is really the type SEND, SEND_ONCE, etc. */
-                   name = dsc->disposition;
-                   object = (ipc_object_t) CAST_MACH_NAME_TO_PORT(dsc->name);
-                   dest_dsc->disposition = ipc_object_copyin_type(name);
-            dest_dsc->name = (mach_port_t)object;
-            dest_dsc->type = MACH_MSG_PORT_DESCRIPTOR;
-               
-                   if (!IO_VALID(object)) {
-                       break;
-                   }
-
-                   ipc_object_copyin_from_kernel(object, name);
-                   
-                   /* CDY avoid circularity when the destination is also */
-                   /* the kernel.  This check should be changed into an  */
-                   /* assert when the new kobject model is in place since*/
-                   /* ports will not be used in kernel to kernel chats   */
-                       
-                   if (((ipc_port_t)remote)->ip_receiver != ipc_space_kernel) {
-                      if ((dest_dsc->disposition == MACH_MSG_TYPE_PORT_RECEIVE) &&
-                          ipc_port_check_circularity((ipc_port_t) object, 
-                                               (ipc_port_t) remote)) {
-                          kmsg->ikm_header->msgh_bits |= 
-                                       MACH_MSGH_BITS_CIRCULAR;
-                      }
-                   }
-                   break;
-               }
-               case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
-        case MACH_MSG_OOL_DESCRIPTOR: {
-                   /* The sender should supply ready-made memory, i.e. a vm_map_copy_t
-             * so we don't need to do anything special. */
-
-                   mach_msg_ool_descriptor32_t *source_dsc = &saddr->out_of_line32;
-                   mach_msg_ool_descriptor_t   *dest_dsc = (typeof(dest_dsc))&daddr->out_of_line;
-
-            vm_offset_t                    address = source_dsc->address;
-            vm_size_t                          size = source_dsc->size;
-            boolean_t                          deallocate = source_dsc->deallocate;
-            mach_msg_copy_options_t            copy = source_dsc->copy;
-            mach_msg_descriptor_type_t  type = source_dsc->type;
-
-            dest_dsc->address = (void *)address;
-            dest_dsc->size = size;
-            dest_dsc->deallocate = deallocate;
-            dest_dsc->copy = copy;
-            dest_dsc->type = type;
-                   break;
-               }
-        case MACH_MSG_OOL_PORTS_DESCRIPTOR: {
-                   ipc_object_t                        *objects;
-                   unsigned int                        j;
-                   mach_msg_type_name_t                name;
-                   mach_msg_ool_ports_descriptor_t     *dest_dsc;
-               
-                   mach_msg_ool_ports_descriptor32_t   *source_dsc = &saddr->ool_ports32;
-            dest_dsc = (typeof(dest_dsc))&daddr->ool_ports;
-
-            boolean_t deallocate = source_dsc->deallocate;
-            mach_msg_copy_options_t copy = source_dsc->copy;
-            mach_msg_size_t port_count = source_dsc->count;
-            mach_msg_type_name_t disposition = source_dsc->disposition;
-
-                   /* this is really the type SEND, SEND_ONCE, etc. */
-                   name = disposition;
-                   disposition = ipc_object_copyin_type(name);
-               
-                   objects = (ipc_object_t *) (uintptr_t)source_dsc->address;
-               
-                   for ( j = 0; j < port_count; j++) {
-                       ipc_object_t object = objects[j];
-                       
-                       if (!IO_VALID(object))
-                           continue;
-                       
-                       ipc_object_copyin_from_kernel(object, name);
-    
-                       if ((disposition == MACH_MSG_TYPE_PORT_RECEIVE) &&
-                           ipc_port_check_circularity(
-                                                      (ipc_port_t) object,
-                                                      (ipc_port_t) remote))
-                           kmsg->ikm_header->msgh_bits |= MACH_MSGH_BITS_CIRCULAR;
-                   }
-
-            dest_dsc->address = objects;
-            dest_dsc->deallocate = deallocate;
-            dest_dsc->copy = copy;
-            dest_dsc->disposition = disposition;
-            dest_dsc->type = MACH_MSG_OOL_PORTS_DESCRIPTOR;
-            dest_dsc->count = port_count;
-                   break;
-               }
-               default: {
-#if    MACH_ASSERT
-                   panic("ipc_kmsg_copyin_from_kernel:  bad descriptor");
-#endif /* MACH_ASSERT */
+
+       if (dest->ip_no_grant) {
+               mach_msg_descriptor_t   *saddr;
+               mach_msg_body_t         *body;
+               mach_msg_type_number_t  i, count;
+
+               body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
+               saddr = (mach_msg_descriptor_t *) (body + 1);
+               count = body->msgh_descriptor_count;
+
+               for (i = 0; i < count; i++, saddr++) {
+                       switch (saddr->type.type) {
+                       case MACH_MSG_PORT_DESCRIPTOR:
+                       case MACH_MSG_OOL_PORTS_DESCRIPTOR:
+                       case MACH_MSG_GUARDED_PORT_DESCRIPTOR:
+                               /* no descriptors have been copied in yet */
+                               ipc_kmsg_clean_partial(kmsg, 0, NULL, 0, 0);
+                               return MACH_SEND_NO_GRANT_DEST;
+                       }
                }
-           }
        }
-    }
-    return MACH_MSG_SUCCESS;
+
+       {
+               mach_msg_legacy_descriptor_t    *saddr;
+               mach_msg_descriptor_t   *daddr;
+               mach_msg_body_t         *body;
+               mach_msg_type_number_t  i, count;
+
+               body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
+               saddr = (typeof(saddr))(body + 1);
+               count = body->msgh_descriptor_count;
+
+               if (count) {
+                       vm_offset_t dsc_adjust = 4 * count;
+                       memmove((char *)(((vm_offset_t)kmsg->ikm_header) - dsc_adjust), kmsg->ikm_header, sizeof(mach_msg_base_t));
+                       kmsg->ikm_header = (mach_msg_header_t *)((vm_offset_t)kmsg->ikm_header - dsc_adjust);
+                       /* Update the message size for the larger in-kernel representation */
+                       kmsg->ikm_header->msgh_size += dsc_adjust;
+               }
+               daddr = (mach_msg_descriptor_t *)((vm_offset_t)kmsg->ikm_header + sizeof(mach_msg_base_t));
+
+               for (i = 0; i < count; i++, saddr++, daddr++) {
+                       switch (saddr->type.type) {
+                       case MACH_MSG_PORT_DESCRIPTOR: {
+                               mach_msg_type_name_t        name;
+                               ipc_object_t                object;
+                               mach_msg_legacy_port_descriptor_t   *dsc;
+                               mach_msg_port_descriptor_t  *dest_dsc;
+
+                               dsc = (typeof(dsc)) & saddr->port;
+                               dest_dsc = &daddr->port;
+
+                               /* this is really the type SEND, SEND_ONCE, etc. */
+                               name = dsc->disposition;
+                               object = ip_to_object(CAST_MACH_NAME_TO_PORT(dsc->name));
+                               dest_dsc->disposition = ipc_object_copyin_type(name);
+                               dest_dsc->name = ip_object_to_port(object);
+                               dest_dsc->type = MACH_MSG_PORT_DESCRIPTOR;
+
+                               if (!IO_VALID(object)) {
+                                       break;
+                               }
+
+                               ipc_object_copyin_from_kernel(object, name);
+
+                               /* CDY avoid circularity when the destination is also */
+                               /* the kernel.  This check should be changed into an  */
+                               /* assert when the new kobject model is in place since*/
+                               /* ports will not be used in kernel to kernel chats   */
+
+                               if (ip_object_to_port(remote)->ip_receiver != ipc_space_kernel) {
+                                       if ((dest_dsc->disposition == MACH_MSG_TYPE_PORT_RECEIVE) &&
+                                           ipc_port_check_circularity(ip_object_to_port(object),
+                                           ip_object_to_port(remote))) {
+                                               kmsg->ikm_header->msgh_bits |=
+                                                   MACH_MSGH_BITS_CIRCULAR;
+                                       }
+                               }
+                               break;
+                       }
+                       case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
+                       case MACH_MSG_OOL_DESCRIPTOR: {
+                               /* The sender should supply ready-made memory, i.e. a vm_map_copy_t
+                                * so we don't need to do anything special. */
+
+                               mach_msg_ool_descriptor32_t *source_dsc = &saddr->out_of_line32;
+                               mach_msg_ool_descriptor_t   *dest_dsc = (typeof(dest_dsc)) & daddr->out_of_line;
+
+                               vm_offset_t             address = source_dsc->address;
+                               vm_size_t                           size = source_dsc->size;
+                               boolean_t                           deallocate = source_dsc->deallocate;
+                               mach_msg_copy_options_t             copy = source_dsc->copy;
+                               mach_msg_descriptor_type_t  type = source_dsc->type;
+
+                               dest_dsc->address = (void *)address;
+                               dest_dsc->size = size;
+                               dest_dsc->deallocate = deallocate;
+                               dest_dsc->copy = copy;
+                               dest_dsc->type = type;
+                               break;
+                       }
+                       case MACH_MSG_OOL_PORTS_DESCRIPTOR: {
+                               ipc_object_t                        *objects;
+                               unsigned int                        j;
+                               mach_msg_type_name_t                name;
+                               mach_msg_ool_ports_descriptor_t     *dest_dsc;
+
+                               mach_msg_ool_ports_descriptor32_t   *source_dsc = &saddr->ool_ports32;
+                               dest_dsc = (typeof(dest_dsc)) & daddr->ool_ports;
+
+                               boolean_t deallocate = source_dsc->deallocate;
+                               mach_msg_copy_options_t copy = source_dsc->copy;
+                               mach_msg_size_t port_count = source_dsc->count;
+                               mach_msg_type_name_t disposition = source_dsc->disposition;
+
+                               /* this is really the type SEND, SEND_ONCE, etc. */
+                               name = disposition;
+                               disposition = ipc_object_copyin_type(name);
+
+                               objects = (ipc_object_t *) (uintptr_t)source_dsc->address;
+
+                               for (j = 0; j < port_count; j++) {
+                                       ipc_object_t object = objects[j];
+
+                                       if (!IO_VALID(object)) {
+                                               continue;
+                                       }
+
+                                       ipc_object_copyin_from_kernel(object, name);
+
+                                       if ((disposition == MACH_MSG_TYPE_PORT_RECEIVE) &&
+                                           ipc_port_check_circularity(ip_object_to_port(object),
+                                           ip_object_to_port(remote))) {
+                                               kmsg->ikm_header->msgh_bits |= MACH_MSGH_BITS_CIRCULAR;
+                                       }
+                               }
+
+                               dest_dsc->address = objects;
+                               dest_dsc->deallocate = deallocate;
+                               dest_dsc->copy = copy;
+                               dest_dsc->disposition = disposition;
+                               dest_dsc->type = MACH_MSG_OOL_PORTS_DESCRIPTOR;
+                               dest_dsc->count = port_count;
+                               break;
+                       }
+                       case MACH_MSG_GUARDED_PORT_DESCRIPTOR: {
+                               mach_msg_type_name_t  disp;
+                               ipc_object_t object;
+                               mach_msg_guarded_port_descriptor32_t   *dsc;
+                               mach_msg_guarded_port_descriptor_t  *dest_dsc;
+
+                               dsc = (typeof(dsc)) & saddr->guarded_port32;
+                               dest_dsc = &daddr->guarded_port;
+
+                               disp = dsc->disposition;
+                               object = ip_to_object(CAST_MACH_NAME_TO_PORT(dsc->name));
+                               assert(dsc->flags == 0);
+                               assert(dsc->context == 0);
+
+                               dest_dsc->disposition = ipc_object_copyin_type(disp);
+                               dest_dsc->name = ip_object_to_port(object);
+                               dest_dsc->type = MACH_MSG_GUARDED_PORT_DESCRIPTOR;
+                               dest_dsc->flags = 0;
+
+                               if (!IO_VALID(object)) {
+                                       break;
+                               }
+
+                               ipc_object_copyin_from_kernel(object, disp);
+
+                               /* CDY avoid circularity when the destination is also */
+                               /* the kernel.  This check should be changed into an  */
+                               /* assert when the new kobject model is in place since*/
+                               /* ports will not be used in kernel to kernel chats   */
+
+                               if (ip_object_to_port(remote)->ip_receiver != ipc_space_kernel) {
+                                       if ((dest_dsc->disposition == MACH_MSG_TYPE_PORT_RECEIVE) &&
+                                           ipc_port_check_circularity(ip_object_to_port(object),
+                                           ip_object_to_port(remote))) {
+                                               kmsg->ikm_header->msgh_bits |=
+                                                   MACH_MSGH_BITS_CIRCULAR;
+                                       }
+                               }
+                               break;
+                       }
+                       default: {
+#if     MACH_ASSERT
+                               panic("ipc_kmsg_copyin_from_kernel:  bad descriptor");
+#endif  /* MACH_ASSERT */
+                       }
+                       }
+               }
+       }
+       return MACH_MSG_SUCCESS;
 }
 #endif /* IKM_SUPPORT_LEGACY */
 
@@ -3593,7 +4171,7 @@ ipc_kmsg_copyin_from_kernel_legacy(
  *             Nothing locked.
  *     Returns:
  *             MACH_MSG_SUCCESS        Copied out port rights.
- *             MACH_RCV_INVALID_NOTIFY 
+ *             MACH_RCV_INVALID_NOTIFY
  *                     Notify is non-null and doesn't name a receive right.
  *                     (Either KERN_INVALID_NAME or KERN_INVALID_RIGHT.)
  *             MACH_RCV_HEADER_ERROR|MACH_MSG_IPC_SPACE
@@ -3609,12 +4187,12 @@ ipc_kmsg_copyin_from_kernel_legacy(
 mach_msg_return_t
 ipc_kmsg_copyout_header(
        ipc_kmsg_t              kmsg,
-       ipc_space_t             space,
-       mach_msg_option_t       option)
+       ipc_space_t             space,
+       mach_msg_option_t       option)
 {
        mach_msg_header_t *msg = kmsg->ikm_header;
        mach_msg_bits_t mbits = msg->msgh_bits;
-       ipc_port_t dest = (ipc_port_t) msg->msgh_remote_port;
+       ipc_port_t dest = msg->msgh_remote_port;
 
        assert(IP_VALID(dest));
 
@@ -3623,295 +4201,329 @@ ipc_kmsg_copyout_header(
         * process all send-possible notfications we received along with
         * the message.
         */
-       ipc_port_spnotify(dest);
-
-    {
-       mach_msg_type_name_t dest_type = MACH_MSGH_BITS_REMOTE(mbits);
-       mach_msg_type_name_t reply_type = MACH_MSGH_BITS_LOCAL(mbits);
-       mach_msg_type_name_t voucher_type = MACH_MSGH_BITS_VOUCHER(mbits);
-       ipc_port_t reply = msg->msgh_local_port;
-       ipc_port_t release_reply_port = IP_NULL;
-       mach_port_name_t dest_name, reply_name;
-
-       ipc_port_t voucher = kmsg->ikm_voucher;
-       ipc_port_t release_voucher_port = IP_NULL;
-       mach_port_name_t voucher_name;
-
-       uint32_t entries_held = 0;
-       boolean_t need_write_lock = FALSE;
-       kern_return_t kr;
-
-       /*
-        * Reserve any potentially needed entries in the target space.
-        * We'll free any unused before unlocking the space.
-        */
-       if (IP_VALID(reply)) {
-               entries_held++;
-               need_write_lock = TRUE;
-       }
-       if (IP_VALID(voucher)) {
-               assert(voucher_type == MACH_MSG_TYPE_MOVE_SEND); 
-
-               if ((option & MACH_RCV_VOUCHER) != 0)
-                       entries_held++;
-               need_write_lock = TRUE;
-       }
-
-       if (need_write_lock) {
+       ipc_port_spnotify(dest);
 
-               is_write_lock(space);
+       {
+               mach_msg_type_name_t dest_type = MACH_MSGH_BITS_REMOTE(mbits);
+               mach_msg_type_name_t reply_type = MACH_MSGH_BITS_LOCAL(mbits);
+               mach_msg_type_name_t voucher_type = MACH_MSGH_BITS_VOUCHER(mbits);
+               ipc_port_t reply = msg->msgh_local_port;
+               ipc_port_t release_reply_port = IP_NULL;
+               mach_port_name_t dest_name, reply_name;
 
-               while(entries_held) {
-                       if (!is_active(space)) {
-                               is_write_unlock(space);
-                               return (MACH_RCV_HEADER_ERROR|
-                                       MACH_MSG_IPC_SPACE);
-                       }
-                               
-                       kr = ipc_entries_hold(space, entries_held);
-                       if (KERN_SUCCESS == kr)
-                               break;
+               ipc_port_t voucher = kmsg->ikm_voucher;
+               ipc_port_t release_voucher_port = IP_NULL;
+               mach_port_name_t voucher_name;
 
-                       kr = ipc_entry_grow_table(space, ITS_SIZE_NONE);
-                       if (KERN_SUCCESS != kr)
-                               return(MACH_RCV_HEADER_ERROR|
-                                      MACH_MSG_IPC_SPACE);
-                       /* space was unlocked and relocked - retry */
-               }
+               uint32_t entries_held = 0;
+               boolean_t need_write_lock = FALSE;
+               kern_return_t kr;
 
-               /* Handle reply port. */
+               /*
+                * Reserve any potentially needed entries in the target space.
+                * We'll free any unused before unlocking the space.
+                */
                if (IP_VALID(reply)) {
-                       ipc_entry_t entry;
+                       entries_held++;
+                       need_write_lock = TRUE;
+               }
+               if (IP_VALID(voucher)) {
+                       assert(voucher_type == MACH_MSG_TYPE_MOVE_SEND);
 
-                       /* Is there already an entry we can use? */
-                       if ((reply_type != MACH_MSG_TYPE_PORT_SEND_ONCE) &&
-                           ipc_right_reverse(space, (ipc_object_t) reply, &reply_name, &entry)) {
-                               /* reply port is locked and active */
-                               assert(entry->ie_bits & MACH_PORT_TYPE_SEND_RECEIVE);
-                       } else {
-                               ip_lock(reply);
-                               if (!ip_active(reply)) {
-                                       ip_unlock(reply);
-                                       
-                                       release_reply_port = reply;
-                                       reply = IP_DEAD;
-                                       reply_name = MACH_PORT_DEAD;
-                                       goto done_with_reply;
-                               }
-                               
-                               /* claim a held entry for the reply port */
-                               assert(entries_held > 0);
-                               entries_held--;
-                               ipc_entry_claim(space, &reply_name, &entry);
-                               assert(IE_BITS_TYPE(entry->ie_bits) == MACH_PORT_TYPE_NONE);
-                               assert(entry->ie_object == IO_NULL); 
-                               entry->ie_object = (ipc_object_t) reply;
+                       if ((option & MACH_RCV_VOUCHER) != 0) {
+                               entries_held++;
                        }
+                       need_write_lock = TRUE;
+               }
 
-                       /* space and reply port are locked and active */
-                       ip_reference(reply);    /* hold onto the reply port */
-
-                       kr = ipc_right_copyout(space, reply_name, entry,
-                                              reply_type, TRUE, (ipc_object_t) reply);
-                       assert(kr == KERN_SUCCESS);
-                       /* reply port is unlocked */
-               } else
-                       reply_name = CAST_MACH_PORT_TO_NAME(reply);
+               if (need_write_lock) {
+                       is_write_lock(space);
 
-       done_with_reply:
+                       while (entries_held) {
+                               if (!is_active(space)) {
+                                       is_write_unlock(space);
+                                       return MACH_RCV_HEADER_ERROR |
+                                              MACH_MSG_IPC_SPACE;
+                               }
 
-               /* Handle voucher port. */
-               if (voucher_type != MACH_MSGH_BITS_ZERO) {
-                       assert(voucher_type == MACH_MSG_TYPE_MOVE_SEND);
+                               kr = ipc_entries_hold(space, entries_held);
+                               if (KERN_SUCCESS == kr) {
+                                       break;
+                               }
 
-                       if (!IP_VALID(voucher)) {
-                               if ((option & MACH_RCV_VOUCHER) == 0) {
-                                       voucher_type = MACH_MSGH_BITS_ZERO;
+                               kr = ipc_entry_grow_table(space, ITS_SIZE_NONE);
+                               if (KERN_SUCCESS != kr) {
+                                       return MACH_RCV_HEADER_ERROR |
+                                              MACH_MSG_IPC_SPACE;
                                }
-                               voucher_name = MACH_PORT_NULL;
-                               goto done_with_voucher;
+                               /* space was unlocked and relocked - retry */
                        }
-                       
-                       /* clear voucher from its hiding place back in the kmsg */
-                       kmsg->ikm_voucher = IP_NULL;
 
-                       if ((option & MACH_RCV_VOUCHER) != 0) {
+                       /* Handle reply port. */
+                       if (IP_VALID(reply)) {
                                ipc_entry_t entry;
 
-                               if (ipc_right_reverse(space, (ipc_object_t) voucher,
-                                                     &voucher_name, &entry)) {
-                                       /* voucher port locked */
-                                       assert(entry->ie_bits & MACH_PORT_TYPE_SEND);
+                               /* Is there already an entry we can use? */
+                               if ((reply_type != MACH_MSG_TYPE_PORT_SEND_ONCE) &&
+                                   ipc_right_reverse(space, ip_to_object(reply), &reply_name, &entry)) {
+                                       /* reply port is locked and active */
+                                       assert(entry->ie_bits & MACH_PORT_TYPE_SEND_RECEIVE);
                                } else {
+                                       ip_lock(reply);
+                                       if (!ip_active(reply)) {
+                                               /* clear the context value */
+                                               reply->ip_reply_context = 0;
+                                               ip_unlock(reply);
+
+                                               release_reply_port = reply;
+                                               reply = IP_DEAD;
+                                               reply_name = MACH_PORT_DEAD;
+                                               goto done_with_reply;
+                                       }
+
+                                       /* claim a held entry for the reply port */
                                        assert(entries_held > 0);
                                        entries_held--;
-                                       ipc_entry_claim(space, &voucher_name, &entry);
+                                       ipc_entry_claim(space, &reply_name, &entry);
                                        assert(IE_BITS_TYPE(entry->ie_bits) == MACH_PORT_TYPE_NONE);
-                                       assert(entry->ie_object == IO_NULL); 
-                                       entry->ie_object = (ipc_object_t) voucher;
-                                       ip_lock(voucher);
+                                       assert(entry->ie_object == IO_NULL);
+                                       entry->ie_object = ip_to_object(reply);
+                               }
+
+                               /* space and reply port are locked and active */
+                               ip_reference(reply);         /* hold onto the reply port */
+
+                               /*
+                                * If the receiver would like to enforce strict reply
+                                * semantics, and the message looks like it expects a reply,
+                                * and contains a voucher, then link the context in the
+                                * voucher with the reply port so that the next message sent
+                                * to the reply port must come from a thread that has a
+                                * matching context (voucher).
+                                */
+                               if (enforce_strict_reply && MACH_RCV_WITH_STRICT_REPLY(option) && IP_VALID(voucher)) {
+                                       if (ipc_kmsg_validate_reply_port_locked(reply, option) != KERN_SUCCESS) {
+                                               /* if the receiver isn't happy with the reply port: fail the receive. */
+                                               ip_unlock(reply);
+                                               ipc_entry_dealloc(space, reply_name, entry);
+                                               is_write_unlock(space);
+                                               ip_release(reply);
+                                               return MACH_RCV_INVALID_REPLY;
+                                       }
+                                       ipc_kmsg_link_reply_context_locked(reply, voucher);
+                               } else {
+                                       /*
+                                        * if the receive did not choose to participate
+                                        * in the strict reply/RPC, then don't enforce
+                                        * anything (as this could lead to booby-trapped
+                                        * messages that kill the server).
+                                        */
+                                       reply->ip_reply_context = 0;
                                }
-                               /* space is locked and active */
-
-                               assert(ip_active(voucher));
-                               assert(ip_kotype(voucher) == IKOT_VOUCHER);
-                               kr = ipc_right_copyout(space, voucher_name, entry,
-                                                      MACH_MSG_TYPE_MOVE_SEND, TRUE, 
-                                                      (ipc_object_t) voucher);
-                               /* voucher port is unlocked */
+
+                               kr = ipc_right_copyout(space, reply_name, entry,
+                                   reply_type, NULL, NULL, ip_to_object(reply));
+                               assert(kr == KERN_SUCCESS);
+                               /* reply port is unlocked */
                        } else {
-                               voucher_type = MACH_MSGH_BITS_ZERO;
-                               release_voucher_port = voucher;
-                               voucher_name = MACH_PORT_NULL;
+                               reply_name = CAST_MACH_PORT_TO_NAME(reply);
                        }
-               } else {
-                       voucher_name = msg->msgh_voucher_port;
-               }
 
-       done_with_voucher:
+done_with_reply:
 
-               ip_lock(dest);
-               is_write_unlock(space);
+                       /* Handle voucher port. */
+                       if (voucher_type != MACH_MSGH_BITS_ZERO) {
+                               assert(voucher_type == MACH_MSG_TYPE_MOVE_SEND);
 
-       } else {
-               /*
-                *      No reply or voucher port!  This is an easy case.
-                *      We only need to have the space locked
-                *      when locking the destination.
-                */
+                               if (!IP_VALID(voucher)) {
+                                       if ((option & MACH_RCV_VOUCHER) == 0) {
+                                               voucher_type = MACH_MSGH_BITS_ZERO;
+                                       }
+                                       voucher_name = MACH_PORT_NULL;
+                                       goto done_with_voucher;
+                               }
 
-               is_read_lock(space);
-               if (!is_active(space)) {
-                       is_read_unlock(space);
-                       return MACH_RCV_HEADER_ERROR|MACH_MSG_IPC_SPACE;
-               }
+                               /* clear voucher from its hiding place back in the kmsg */
+                               kmsg->ikm_voucher = IP_NULL;
+
+                               if ((option & MACH_RCV_VOUCHER) != 0) {
+                                       ipc_entry_t entry;
+
+                                       if (ipc_right_reverse(space, ip_to_object(voucher),
+                                           &voucher_name, &entry)) {
+                                               /* voucher port locked */
+                                               assert(entry->ie_bits & MACH_PORT_TYPE_SEND);
+                                       } else {
+                                               assert(entries_held > 0);
+                                               entries_held--;
+                                               ipc_entry_claim(space, &voucher_name, &entry);
+                                               assert(IE_BITS_TYPE(entry->ie_bits) == MACH_PORT_TYPE_NONE);
+                                               assert(entry->ie_object == IO_NULL);
+                                               entry->ie_object = ip_to_object(voucher);
+                                               ip_lock(voucher);
+                                       }
+                                       /* space is locked and active */
+                                       require_ip_active(voucher);
+                                       assert(ip_kotype(voucher) == IKOT_VOUCHER);
+                                       kr = ipc_right_copyout(space, voucher_name, entry,
+                                           MACH_MSG_TYPE_MOVE_SEND, NULL, NULL,
+                                           ip_to_object(voucher));
+                                       /* voucher port is unlocked */
+                               } else {
+                                       voucher_type = MACH_MSGH_BITS_ZERO;
+                                       release_voucher_port = voucher;
+                                       voucher_name = MACH_PORT_NULL;
+                               }
+                       } else {
+                               voucher_name = msg->msgh_voucher_port;
+                       }
 
-               ip_lock(dest);
-               is_read_unlock(space);
+done_with_voucher:
 
-               reply_name = CAST_MACH_PORT_TO_NAME(reply);
+                       ip_lock(dest);
+                       is_write_unlock(space);
+               } else {
+                       /*
+                        *      No reply or voucher port!  This is an easy case.
+                        *      We only need to have the space locked
+                        *      when locking the destination.
+                        */
 
-               if (voucher_type != MACH_MSGH_BITS_ZERO) {
-                       assert(voucher_type == MACH_MSG_TYPE_MOVE_SEND);
-                       if ((option & MACH_RCV_VOUCHER) == 0) {
-                               voucher_type = MACH_MSGH_BITS_ZERO;
+                       is_read_lock(space);
+                       if (!is_active(space)) {
+                               is_read_unlock(space);
+                               return MACH_RCV_HEADER_ERROR | MACH_MSG_IPC_SPACE;
+                       }
+
+                       ip_lock(dest);
+                       is_read_unlock(space);
+
+                       reply_name = CAST_MACH_PORT_TO_NAME(reply);
+
+                       if (voucher_type != MACH_MSGH_BITS_ZERO) {
+                               assert(voucher_type == MACH_MSG_TYPE_MOVE_SEND);
+                               if ((option & MACH_RCV_VOUCHER) == 0) {
+                                       voucher_type = MACH_MSGH_BITS_ZERO;
+                               }
+                               voucher_name = MACH_PORT_NULL;
+                       } else {
+                               voucher_name = msg->msgh_voucher_port;
                        }
-                       voucher_name = MACH_PORT_NULL;
-               } else {
-                       voucher_name = msg->msgh_voucher_port;
                }
-       }
 
-       /*
-        *      At this point, the space is unlocked and the destination
-        *      port is locked.  (Lock taken while space was locked.)
-        *      reply_name is taken care of; we still need dest_name.
-        *      We still hold a ref for reply (if it is valid).
-        *
-        *      If the space holds receive rights for the destination,
-        *      we return its name for the right.  Otherwise the task
-        *      managed to destroy or give away the receive right between
-        *      receiving the message and this copyout.  If the destination
-        *      is dead, return MACH_PORT_DEAD, and if the receive right
-        *      exists somewhere else (another space, in transit)
-        *      return MACH_PORT_NULL.
-        *
-        *      Making this copyout operation atomic with the previous
-        *      copyout of the reply port is a bit tricky.  If there was
-        *      no real reply port (it wasn't IP_VALID) then this isn't
-        *      an issue.  If the reply port was dead at copyout time,
-        *      then we are OK, because if dest is dead we serialize
-        *      after the death of both ports and if dest is alive
-        *      we serialize after reply died but before dest's (later) death.
-        *      So assume reply was alive when we copied it out.  If dest
-        *      is alive, then we are OK because we serialize before
-        *      the ports' deaths.  So assume dest is dead when we look at it.
-        *      If reply dies/died after dest, then we are OK because
-        *      we serialize after dest died but before reply dies.
-        *      So the hard case is when reply is alive at copyout,
-        *      dest is dead at copyout, and reply died before dest died.
-        *      In this case pretend that dest is still alive, so
-        *      we serialize while both ports are alive.
-        *
-        *      Because the space lock is held across the copyout of reply
-        *      and locking dest, the receive right for dest can't move
-        *      in or out of the space while the copyouts happen, so
-        *      that isn't an atomicity problem.  In the last hard case
-        *      above, this implies that when dest is dead that the
-        *      space couldn't have had receive rights for dest at
-        *      the time reply was copied-out, so when we pretend
-        *      that dest is still alive, we can return MACH_PORT_NULL.
-        *
-        *      If dest == reply, then we have to make it look like
-        *      either both copyouts happened before the port died,
-        *      or both happened after the port died.  This special
-        *      case works naturally if the timestamp comparison
-        *      is done correctly.
-        */
+               /*
+                *      At this point, the space is unlocked and the destination
+                *      port is locked.  (Lock taken while space was locked.)
+                *      reply_name is taken care of; we still need dest_name.
+                *      We still hold a ref for reply (if it is valid).
+                *
+                *      If the space holds receive rights for the destination,
+                *      we return its name for the right.  Otherwise the task
+                *      managed to destroy or give away the receive right between
+                *      receiving the message and this copyout.  If the destination
+                *      is dead, return MACH_PORT_DEAD, and if the receive right
+                *      exists somewhere else (another space, in transit)
+                *      return MACH_PORT_NULL.
+                *
+                *      Making this copyout operation atomic with the previous
+                *      copyout of the reply port is a bit tricky.  If there was
+                *      no real reply port (it wasn't IP_VALID) then this isn't
+                *      an issue.  If the reply port was dead at copyout time,
+                *      then we are OK, because if dest is dead we serialize
+                *      after the death of both ports and if dest is alive
+                *      we serialize after reply died but before dest's (later) death.
+                *      So assume reply was alive when we copied it out.  If dest
+                *      is alive, then we are OK because we serialize before
+                *      the ports' deaths.  So assume dest is dead when we look at it.
+                *      If reply dies/died after dest, then we are OK because
+                *      we serialize after dest died but before reply dies.
+                *      So the hard case is when reply is alive at copyout,
+                *      dest is dead at copyout, and reply died before dest died.
+                *      In this case pretend that dest is still alive, so
+                *      we serialize while both ports are alive.
+                *
+                *      Because the space lock is held across the copyout of reply
+                *      and locking dest, the receive right for dest can't move
+                *      in or out of the space while the copyouts happen, so
+                *      that isn't an atomicity problem.  In the last hard case
+                *      above, this implies that when dest is dead that the
+                *      space couldn't have had receive rights for dest at
+                *      the time reply was copied-out, so when we pretend
+                *      that dest is still alive, we can return MACH_PORT_NULL.
+                *
+                *      If dest == reply, then we have to make it look like
+                *      either both copyouts happened before the port died,
+                *      or both happened after the port died.  This special
+                *      case works naturally if the timestamp comparison
+                *      is done correctly.
+                */
 
-       if (ip_active(dest)) {
-               ipc_object_copyout_dest(space, (ipc_object_t) dest,
-                                       dest_type, &dest_name);
-               /* dest is unlocked */
+               if (ip_active(dest)) {
+                       ipc_object_copyout_dest(space, ip_to_object(dest),
+                           dest_type, &dest_name);
+                       /* dest is unlocked */
+               } else {
+                       ipc_port_timestamp_t timestamp;
 
-       } else {
-               ipc_port_timestamp_t timestamp;
+                       timestamp = dest->ip_timestamp;
+                       ip_unlock(dest);
+                       ip_release(dest);
 
-               timestamp = dest->ip_timestamp;
-               ip_unlock(dest);
-               ip_release(dest);
+                       if (IP_VALID(reply)) {
+                               ip_lock(reply);
+                               if (ip_active(reply) ||
+                                   IP_TIMESTAMP_ORDER(timestamp,
+                                   reply->ip_timestamp)) {
+                                       dest_name = MACH_PORT_DEAD;
+                               } else {
+                                       dest_name = MACH_PORT_NULL;
+                               }
+                               ip_unlock(reply);
+                       } else {
+                               dest_name = MACH_PORT_DEAD;
+                       }
+               }
 
                if (IP_VALID(reply)) {
-                       ip_lock(reply);
-                       if (ip_active(reply) ||
-                           IP_TIMESTAMP_ORDER(timestamp,
-                                              reply->ip_timestamp))
-                               dest_name = MACH_PORT_DEAD;
-                       else
-                               dest_name = MACH_PORT_NULL;
-                       ip_unlock(reply);
-               } else
-                       dest_name = MACH_PORT_DEAD;
-       }
+                       ip_release(reply);
+               }
 
-       if (IP_VALID(reply))
-               ip_release(reply);
+               if (IP_VALID(release_reply_port)) {
+                       if (reply_type == MACH_MSG_TYPE_PORT_SEND_ONCE) {
+                               ipc_port_release_sonce(release_reply_port);
+                       } else {
+                               ipc_port_release_send(release_reply_port);
+                       }
+               }
 
-       if (IP_VALID(release_reply_port)) {
-               if (reply_type == MACH_MSG_TYPE_PORT_SEND_ONCE)
-                       ipc_port_release_sonce(release_reply_port);
-               else
-                       ipc_port_release_send(release_reply_port);
-       }
+               if ((option & MACH_RCV_VOUCHER) != 0) {
+                       KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_IPC, MACH_IPC_MSG_RECV) | DBG_FUNC_NONE,
+                           VM_KERNEL_ADDRPERM((uintptr_t)kmsg),
+                           (uintptr_t)kmsg->ikm_header->msgh_bits,
+                           (uintptr_t)kmsg->ikm_header->msgh_id,
+                           VM_KERNEL_ADDRPERM((uintptr_t)unsafe_convert_port_to_voucher(voucher)),
+                           0);
+               } else {
+                       KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_IPC, MACH_IPC_MSG_RECV_VOUCHER_REFUSED) | DBG_FUNC_NONE,
+                           VM_KERNEL_ADDRPERM((uintptr_t)kmsg),
+                           (uintptr_t)kmsg->ikm_header->msgh_bits,
+                           (uintptr_t)kmsg->ikm_header->msgh_id,
+                           VM_KERNEL_ADDRPERM((uintptr_t)unsafe_convert_port_to_voucher(voucher)),
+                           0);
+               }
 
-       if (IP_VALID(release_voucher_port))
-               ipc_port_release_send(release_voucher_port);
+               if (IP_VALID(release_voucher_port)) {
+                       ipc_port_release_send(release_voucher_port);
+               }
 
+               msg->msgh_bits = MACH_MSGH_BITS_SET(reply_type, dest_type,
+                   voucher_type, mbits);
+               msg->msgh_local_port = CAST_MACH_NAME_TO_PORT(dest_name);
+               msg->msgh_remote_port = CAST_MACH_NAME_TO_PORT(reply_name);
+               msg->msgh_voucher_port = voucher_name;
+       }
 
-       if ((option & MACH_RCV_VOUCHER) != 0) {
-           KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_IPC, MACH_IPC_MSG_RECV) | DBG_FUNC_NONE,
-                                 VM_KERNEL_ADDRPERM((uintptr_t)kmsg),
-                                 (uintptr_t)kmsg->ikm_header->msgh_bits,
-                                 (uintptr_t)kmsg->ikm_header->msgh_id,
-                                 VM_KERNEL_ADDRPERM((uintptr_t)unsafe_convert_port_to_voucher(voucher)),
-                                 0);
-       } else {
-           KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_IPC, MACH_IPC_MSG_RECV_VOUCHER_REFUSED) | DBG_FUNC_NONE,
-                                 VM_KERNEL_ADDRPERM((uintptr_t)kmsg),
-                                 (uintptr_t)kmsg->ikm_header->msgh_bits,
-                                 (uintptr_t)kmsg->ikm_header->msgh_id,
-                                 VM_KERNEL_ADDRPERM((uintptr_t)unsafe_convert_port_to_voucher(voucher)),
-                                 0);
-       }
-
-       msg->msgh_bits = MACH_MSGH_BITS_SET(reply_type, dest_type,
-                                           voucher_type, mbits);
-       msg->msgh_local_port = CAST_MACH_NAME_TO_PORT(dest_name);
-       msg->msgh_remote_port = CAST_MACH_NAME_TO_PORT(reply_name);
-       msg->msgh_voucher_port = voucher_name;
-    }
-
-    return MACH_MSG_SUCCESS;
+       return MACH_MSG_SUCCESS;
 }
 
 /*
@@ -3933,10 +4545,12 @@ ipc_kmsg_copyout_header(
 
 mach_msg_return_t
 ipc_kmsg_copyout_object(
-       ipc_space_t             space,
-       ipc_object_t            object,
-       mach_msg_type_name_t    msgt_name,
-       mach_port_name_t        *namep)
+       ipc_space_t             space,
+       ipc_object_t            object,
+       mach_msg_type_name_t    msgt_name,
+       mach_port_context_t     *context,
+       mach_msg_guard_flags_t  *guard_flags,
+       mach_port_name_t        *namep)
 {
        kern_return_t kr;
 
@@ -3945,69 +4559,61 @@ ipc_kmsg_copyout_object(
                return MACH_MSG_SUCCESS;
        }
 
-       kr = ipc_object_copyout(space, object, msgt_name, TRUE, namep);
+       kr = ipc_object_copyout(space, object, msgt_name, context, guard_flags, namep);
        if (kr != KERN_SUCCESS) {
                ipc_object_destroy(object, msgt_name);
 
-               if (kr == KERN_INVALID_CAPABILITY)
+               if (kr == KERN_INVALID_CAPABILITY) {
                        *namep = MACH_PORT_DEAD;
-               else {
+               else {
                        *namep = MACH_PORT_NULL;
 
-                       if (kr == KERN_RESOURCE_SHORTAGE)
+                       if (kr == KERN_RESOURCE_SHORTAGE) {
                                return MACH_MSG_IPC_KERNEL;
-                       else
+                       } else {
                                return MACH_MSG_IPC_SPACE;
+                       }
                }
        }
 
        return MACH_MSG_SUCCESS;
 }
 
-mach_msg_descriptor_t *
+static mach_msg_descriptor_t *
 ipc_kmsg_copyout_port_descriptor(mach_msg_descriptor_t *dsc,
-        mach_msg_descriptor_t *user_dsc,
-        ipc_space_t space,
-        kern_return_t *mr);
-mach_msg_descriptor_t *
-ipc_kmsg_copyout_port_descriptor(mach_msg_descriptor_t *dsc,
-        mach_msg_descriptor_t *dest_dsc,
-        ipc_space_t space, 
-        kern_return_t *mr)
+    mach_msg_descriptor_t *dest_dsc,
+    ipc_space_t space,
+    kern_return_t *mr)
 {
-    mach_port_t                        port;
-    mach_port_name_t           name;
-    mach_msg_type_name_t               disp;
-
-
-    /* Copyout port right carried in the message */
-    port = dsc->port.name;
-    disp = dsc->port.disposition;
-    *mr |= ipc_kmsg_copyout_object(space, 
-            (ipc_object_t)port, 
-            disp, 
-            &name);
-
-    if(current_task() == kernel_task)
-    {
-        mach_msg_port_descriptor_t *user_dsc = (typeof(user_dsc))dest_dsc;
-        user_dsc--; // point to the start of this port descriptor
-        bzero((void *)user_dsc, sizeof(*user_dsc));
-        user_dsc->name = CAST_MACH_NAME_TO_PORT(name);
-        user_dsc->disposition = disp;
-        user_dsc->type = MACH_MSG_PORT_DESCRIPTOR;
-        dest_dsc = (typeof(dest_dsc))user_dsc;
-    } else {
-        mach_msg_legacy_port_descriptor_t *user_dsc = (typeof(user_dsc))dest_dsc;
-        user_dsc--; // point to the start of this port descriptor
-        bzero((void *)user_dsc, sizeof(*user_dsc));
-        user_dsc->name = CAST_MACH_PORT_TO_NAME(name);
-        user_dsc->disposition = disp;
-        user_dsc->type = MACH_MSG_PORT_DESCRIPTOR;
-        dest_dsc = (typeof(dest_dsc))user_dsc;
-    }
-
-    return (mach_msg_descriptor_t *)dest_dsc;
+       mach_port_t                 port;
+       mach_port_name_t            name;
+       mach_msg_type_name_t                disp;
+
+       /* Copyout port right carried in the message */
+       port = dsc->port.name;
+       disp = dsc->port.disposition;
+       *mr |= ipc_kmsg_copyout_object(space,
+           ip_to_object(port), disp, NULL, NULL, &name);
+
+       if (current_task() == kernel_task) {
+               mach_msg_port_descriptor_t *user_dsc = (typeof(user_dsc))dest_dsc;
+               user_dsc--;         // point to the start of this port descriptor
+               bzero((void *)user_dsc, sizeof(*user_dsc));
+               user_dsc->name = CAST_MACH_NAME_TO_PORT(name);
+               user_dsc->disposition = disp;
+               user_dsc->type = MACH_MSG_PORT_DESCRIPTOR;
+               dest_dsc = (typeof(dest_dsc))user_dsc;
+       } else {
+               mach_msg_legacy_port_descriptor_t *user_dsc = (typeof(user_dsc))dest_dsc;
+               user_dsc--;         // point to the start of this port descriptor
+               bzero((void *)user_dsc, sizeof(*user_dsc));
+               user_dsc->name = CAST_MACH_PORT_TO_NAME(name);
+               user_dsc->disposition = disp;
+               user_dsc->type = MACH_MSG_PORT_DESCRIPTOR;
+               dest_dsc = (typeof(dest_dsc))user_dsc;
+       }
+
+       return (mach_msg_descriptor_t *)dest_dsc;
 }
 
 mach_msg_descriptor_t *
@@ -4015,247 +4621,326 @@ ipc_kmsg_copyout_ool_descriptor(mach_msg_ool_descriptor_t *dsc, mach_msg_descrip
 mach_msg_descriptor_t *
 ipc_kmsg_copyout_ool_descriptor(mach_msg_ool_descriptor_t *dsc, mach_msg_descriptor_t *user_dsc, int is_64bit, vm_map_t map, mach_msg_return_t *mr)
 {
-    vm_map_copy_t                      copy;
-    vm_map_address_t                   rcv_addr;
-    mach_msg_copy_options_t            copy_options;
-    vm_map_size_t                      size;
-    mach_msg_descriptor_type_t dsc_type;
-
-    //SKIP_PORT_DESCRIPTORS(saddr, sdsc_count);
-
-    copy = (vm_map_copy_t)dsc->address;
-    size = (vm_map_size_t)dsc->size;
-    copy_options = dsc->copy;
-    assert(copy_options != MACH_MSG_KALLOC_COPY_T);
-    dsc_type = dsc->type;
-
-    if (copy != VM_MAP_COPY_NULL) {
-       kern_return_t kr;
+       vm_map_copy_t                       copy;
+       vm_map_address_t                    rcv_addr;
+       mach_msg_copy_options_t             copy_options;
+       vm_map_size_t                       size;
+       mach_msg_descriptor_type_t  dsc_type;
+
+       //SKIP_PORT_DESCRIPTORS(saddr, sdsc_count);
+
+       copy = (vm_map_copy_t)dsc->address;
+       size = (vm_map_size_t)dsc->size;
+       copy_options = dsc->copy;
+       assert(copy_options != MACH_MSG_KALLOC_COPY_T);
+       dsc_type = dsc->type;
+
+       if (copy != VM_MAP_COPY_NULL) {
+               kern_return_t kr;
+
+               rcv_addr = 0;
+               if (vm_map_copy_validate_size(map, copy, &size) == FALSE) {
+                       panic("Inconsistent OOL/copyout size on %p: expected %d, got %lld @%p",
+                           dsc, dsc->size, (unsigned long long)copy->size, copy);
+               }
+               kr = vm_map_copyout_size(map, &rcv_addr, copy, size);
+               if (kr != KERN_SUCCESS) {
+                       if (kr == KERN_RESOURCE_SHORTAGE) {
+                               *mr |= MACH_MSG_VM_KERNEL;
+                       } else {
+                               *mr |= MACH_MSG_VM_SPACE;
+                       }
+                       vm_map_copy_discard(copy);
+                       rcv_addr = 0;
+                       size = 0;
+               }
+       } else {
+               rcv_addr = 0;
+               size = 0;
+       }
 
-        rcv_addr = 0;
-       if (vm_map_copy_validate_size(map, copy, &size) == FALSE)
-               panic("Inconsistent OOL/copyout size on %p: expected %d, got %lld @%p",
-                     dsc, dsc->size, (unsigned long long)copy->size, copy);
-        kr = vm_map_copyout_size(map, &rcv_addr, copy, size);
-        if (kr != KERN_SUCCESS) {
-            if (kr == KERN_RESOURCE_SHORTAGE)
-                *mr |= MACH_MSG_VM_KERNEL;
-            else
-                *mr |= MACH_MSG_VM_SPACE;
-            vm_map_copy_discard(copy);
-            rcv_addr = 0;
-            size = 0;
-        }
-    } else {
-        rcv_addr = 0;
-        size = 0;
-    }
-
-    /*
-     * Now update the descriptor as the user would see it.
-     * This may require expanding the descriptor to the user
-     * visible size.  There is already space allocated for
-     * this in what naddr points to.
-     */
-    if(current_task() == kernel_task)
-    {
-        mach_msg_ool_descriptor_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
-        user_ool_dsc--;
-        bzero((void *)user_ool_dsc, sizeof(*user_ool_dsc));
-
-        user_ool_dsc->address = (void *)(uintptr_t)rcv_addr;
-        user_ool_dsc->deallocate = (copy_options == MACH_MSG_VIRTUAL_COPY) ?
-            TRUE : FALSE;
-        user_ool_dsc->copy = copy_options;
-        user_ool_dsc->type = dsc_type;
-        user_ool_dsc->size = (mach_msg_size_t)size;
-
-        user_dsc = (typeof(user_dsc))user_ool_dsc;
-    } else if (is_64bit) {
-        mach_msg_ool_descriptor64_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
-        user_ool_dsc--;
-        bzero((void *)user_ool_dsc, sizeof(*user_ool_dsc));
-
-        user_ool_dsc->address = rcv_addr;
-        user_ool_dsc->deallocate = (copy_options == MACH_MSG_VIRTUAL_COPY) ?
-            TRUE : FALSE;
-        user_ool_dsc->copy = copy_options;
-        user_ool_dsc->type = dsc_type;
-        user_ool_dsc->size = (mach_msg_size_t)size;
-
-        user_dsc = (typeof(user_dsc))user_ool_dsc;
-    } else {
-        mach_msg_ool_descriptor32_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
-        user_ool_dsc--;
-        bzero((void *)user_ool_dsc, sizeof(*user_ool_dsc));
-
-        user_ool_dsc->address = CAST_DOWN_EXPLICIT(uint32_t, rcv_addr);
-        user_ool_dsc->size = (mach_msg_size_t)size;
-        user_ool_dsc->deallocate = (copy_options == MACH_MSG_VIRTUAL_COPY) ?
-            TRUE : FALSE;
-        user_ool_dsc->copy = copy_options;
-        user_ool_dsc->type = dsc_type;
-
-        user_dsc = (typeof(user_dsc))user_ool_dsc;
-    }
-    return user_dsc;
+       /*
+        * Now update the descriptor as the user would see it.
+        * This may require expanding the descriptor to the user
+        * visible size.  There is already space allocated for
+        * this in what naddr points to.
+        */
+       if (current_task() == kernel_task) {
+               mach_msg_ool_descriptor_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
+               user_ool_dsc--;
+               bzero((void *)user_ool_dsc, sizeof(*user_ool_dsc));
+
+               user_ool_dsc->address = (void *)(uintptr_t)rcv_addr;
+               user_ool_dsc->deallocate = (copy_options == MACH_MSG_VIRTUAL_COPY) ?
+                   TRUE : FALSE;
+               user_ool_dsc->copy = copy_options;
+               user_ool_dsc->type = dsc_type;
+               user_ool_dsc->size = (mach_msg_size_t)size;
+
+               user_dsc = (typeof(user_dsc))user_ool_dsc;
+       } else if (is_64bit) {
+               mach_msg_ool_descriptor64_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
+               user_ool_dsc--;
+               bzero((void *)user_ool_dsc, sizeof(*user_ool_dsc));
+
+               user_ool_dsc->address = rcv_addr;
+               user_ool_dsc->deallocate = (copy_options == MACH_MSG_VIRTUAL_COPY) ?
+                   TRUE : FALSE;
+               user_ool_dsc->copy = copy_options;
+               user_ool_dsc->type = dsc_type;
+               user_ool_dsc->size = (mach_msg_size_t)size;
+
+               user_dsc = (typeof(user_dsc))user_ool_dsc;
+       } else {
+               mach_msg_ool_descriptor32_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
+               user_ool_dsc--;
+               bzero((void *)user_ool_dsc, sizeof(*user_ool_dsc));
+
+               user_ool_dsc->address = CAST_DOWN_EXPLICIT(uint32_t, rcv_addr);
+               user_ool_dsc->size = (mach_msg_size_t)size;
+               user_ool_dsc->deallocate = (copy_options == MACH_MSG_VIRTUAL_COPY) ?
+                   TRUE : FALSE;
+               user_ool_dsc->copy = copy_options;
+               user_ool_dsc->type = dsc_type;
+
+               user_dsc = (typeof(user_dsc))user_ool_dsc;
+       }
+       return user_dsc;
 }
 
 mach_msg_descriptor_t *
 ipc_kmsg_copyout_ool_ports_descriptor(mach_msg_ool_ports_descriptor_t *dsc,
-        mach_msg_descriptor_t *user_dsc,
-        int is_64bit,
-        vm_map_t map,
-        ipc_space_t space,
-        ipc_kmsg_t kmsg,
-        mach_msg_return_t *mr);
+    mach_msg_descriptor_t *user_dsc,
+    int is_64bit,
+    vm_map_t map,
+    ipc_space_t space,
+    ipc_kmsg_t kmsg,
+    mach_msg_return_t *mr);
 mach_msg_descriptor_t *
 ipc_kmsg_copyout_ool_ports_descriptor(mach_msg_ool_ports_descriptor_t *dsc,
-        mach_msg_descriptor_t *user_dsc,
-        int is_64bit,
-        vm_map_t map,
-        ipc_space_t space,
-        ipc_kmsg_t kmsg,
-        mach_msg_return_t *mr)
+    mach_msg_descriptor_t *user_dsc,
+    int is_64bit,
+    vm_map_t map,
+    ipc_space_t space,
+    ipc_kmsg_t kmsg,
+    mach_msg_return_t *mr)
 {
-    mach_vm_offset_t           rcv_addr = 0;
-    mach_msg_type_name_t               disp;
-    mach_msg_type_number_t             count, i;
-    vm_size_t                          ports_length, names_length;
-
-    mach_msg_copy_options_t copy_options = MACH_MSG_VIRTUAL_COPY;
+       mach_vm_offset_t            rcv_addr = 0;
+       mach_msg_type_name_t                disp;
+       mach_msg_type_number_t              count, i;
+       vm_size_t                           ports_length, names_length;
 
-    //SKIP_PORT_DESCRIPTORS(saddr, sdsc_count);
+       mach_msg_copy_options_t copy_options = MACH_MSG_VIRTUAL_COPY;
 
-    count = dsc->count;
-    disp = dsc->disposition;
-    ports_length = count * sizeof(mach_port_t);
-    names_length = count * sizeof(mach_port_name_t);
+       //SKIP_PORT_DESCRIPTORS(saddr, sdsc_count);
 
-    if (ports_length != 0 && dsc->address != 0) {
+       count = dsc->count;
+       disp = dsc->disposition;
+       ports_length = count * sizeof(mach_port_t);
+       names_length = count * sizeof(mach_port_name_t);
 
-        /*
-         * Check to see if there is an overwrite descriptor
-         * specified in the scatter list for this ool data.
-         * The descriptor has already been verified.
-         */
+       if (ports_length != 0 && dsc->address != 0) {
+               /*
+                * Check to see if there is an overwrite descriptor
+                * specified in the scatter list for this ool data.
+                * The descriptor has already been verified.
+                */
 #if 0
-        if (saddr != MACH_MSG_DESCRIPTOR_NULL) {
-            if (differs) {
-                OTHER_OOL_DESCRIPTOR *scatter_dsc;
-
-                scatter_dsc = (OTHER_OOL_DESCRIPTOR *)saddr;
-                rcv_addr = (mach_vm_offset_t) scatter_dsc->address;
-                copy_options = scatter_dsc->copy;
-            } else {
-                mach_msg_ool_descriptor_t *scatter_dsc;
-
-                scatter_dsc = &saddr->out_of_line;
-                rcv_addr = CAST_USER_ADDR_T(scatter_dsc->address);
-                copy_options = scatter_dsc->copy;
-            }
-            INCREMENT_SCATTER(saddr, sdsc_count, differs);
-        }
+               if (saddr != MACH_MSG_DESCRIPTOR_NULL) {
+                       if (differs) {
+                               OTHER_OOL_DESCRIPTOR *scatter_dsc;
+
+                               scatter_dsc = (OTHER_OOL_DESCRIPTOR *)saddr;
+                               rcv_addr = (mach_vm_offset_t) scatter_dsc->address;
+                               copy_options = scatter_dsc->copy;
+                       } else {
+                               mach_msg_ool_descriptor_t *scatter_dsc;
+
+                               scatter_dsc = &saddr->out_of_line;
+                               rcv_addr = CAST_USER_ADDR_T(scatter_dsc->address);
+                               copy_options = scatter_dsc->copy;
+                       }
+                       INCREMENT_SCATTER(saddr, sdsc_count, differs);
+               }
+#endif
+
+               if (copy_options == MACH_MSG_VIRTUAL_COPY) {
+                       /*
+                        * Dynamically allocate the region
+                        */
+                       vm_tag_t tag;
+                       if (vm_kernel_map_is_kernel(map)) {
+                               tag = VM_KERN_MEMORY_IPC;
+                       } else {
+                               tag = VM_MEMORY_MACH_MSG;
+                       }
+
+                       kern_return_t kr;
+                       if ((kr = mach_vm_allocate_kernel(map, &rcv_addr,
+                           (mach_vm_size_t)names_length,
+                           VM_FLAGS_ANYWHERE, tag)) != KERN_SUCCESS) {
+                               ipc_kmsg_clean_body(kmsg, 1, (mach_msg_descriptor_t *)dsc);
+                               rcv_addr = 0;
+
+                               if (kr == KERN_RESOURCE_SHORTAGE) {
+                                       *mr |= MACH_MSG_VM_KERNEL;
+                               } else {
+                                       *mr |= MACH_MSG_VM_SPACE;
+                               }
+                       }
+               }
+
+               /*
+                * Handle the port rights and copy out the names
+                * for those rights out to user-space.
+                */
+               if (rcv_addr != 0) {
+                       ipc_object_t *objects = (ipc_object_t *) dsc->address;
+                       mach_port_name_t *names = (mach_port_name_t *) dsc->address;
+
+                       /* copyout port rights carried in the message */
+
+                       for (i = 0; i < count; i++) {
+                               ipc_object_t object = objects[i];
+
+                               *mr |= ipc_kmsg_copyout_object(space, object,
+                                   disp, NULL, NULL, &names[i]);
+                       }
+
+                       /* copyout to memory allocated above */
+                       void *data = dsc->address;
+                       if (copyoutmap(map, data, rcv_addr, names_length) != KERN_SUCCESS) {
+                               *mr |= MACH_MSG_VM_SPACE;
+                       }
+                       kfree(data, ports_length);
+               }
+       } else {
+               rcv_addr = 0;
+       }
+
+       /*
+        * Now update the descriptor based on the information
+        * calculated above.
+        */
+       if (current_task() == kernel_task) {
+               mach_msg_ool_ports_descriptor_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
+               user_ool_dsc--;
+               bzero((void *)user_ool_dsc, sizeof(*user_ool_dsc));
+
+               user_ool_dsc->address = (void *)(uintptr_t)rcv_addr;
+               user_ool_dsc->deallocate = (copy_options == MACH_MSG_VIRTUAL_COPY) ?
+                   TRUE : FALSE;
+               user_ool_dsc->copy = copy_options;
+               user_ool_dsc->disposition = disp;
+               user_ool_dsc->type = MACH_MSG_OOL_PORTS_DESCRIPTOR;
+               user_ool_dsc->count = count;
+
+               user_dsc = (typeof(user_dsc))user_ool_dsc;
+       } else if (is_64bit) {
+               mach_msg_ool_ports_descriptor64_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
+               user_ool_dsc--;
+               bzero((void *)user_ool_dsc, sizeof(*user_ool_dsc));
+
+               user_ool_dsc->address = rcv_addr;
+               user_ool_dsc->deallocate = (copy_options == MACH_MSG_VIRTUAL_COPY) ?
+                   TRUE : FALSE;
+               user_ool_dsc->copy = copy_options;
+               user_ool_dsc->disposition = disp;
+               user_ool_dsc->type = MACH_MSG_OOL_PORTS_DESCRIPTOR;
+               user_ool_dsc->count = count;
+
+               user_dsc = (typeof(user_dsc))user_ool_dsc;
+       } else {
+               mach_msg_ool_ports_descriptor32_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
+               user_ool_dsc--;
+               bzero((void *)user_ool_dsc, sizeof(*user_ool_dsc));
+
+               user_ool_dsc->address = CAST_DOWN_EXPLICIT(uint32_t, rcv_addr);
+               user_ool_dsc->count = count;
+               user_ool_dsc->deallocate = (copy_options == MACH_MSG_VIRTUAL_COPY) ?
+                   TRUE : FALSE;
+               user_ool_dsc->copy = copy_options;
+               user_ool_dsc->disposition = disp;
+               user_ool_dsc->type = MACH_MSG_OOL_PORTS_DESCRIPTOR;
+
+               user_dsc = (typeof(user_dsc))user_ool_dsc;
+       }
+       return user_dsc;
+}
+
+static mach_msg_descriptor_t *
+ipc_kmsg_copyout_guarded_port_descriptor(
+       mach_msg_guarded_port_descriptor_t *dsc,
+       mach_msg_descriptor_t *dest_dsc,
+       int is_64bit,
+       __unused ipc_kmsg_t  kmsg,
+       ipc_space_t space,
+       mach_msg_option_t option,
+       kern_return_t *mr)
+{
+       mach_port_t                 port;
+       mach_port_name_t            name = MACH_PORT_NULL;
+       mach_msg_type_name_t        disp;
+       mach_msg_guard_flags_t      guard_flags;
+       mach_port_context_t         context;
+
+       /* Copyout port right carried in the message */
+       port = dsc->name;
+       disp = dsc->disposition;
+       guard_flags = dsc->flags;
+       context = 0;
+
+       /* Currently kernel_task doesnt support receiving guarded port descriptors */
+       struct knote *kn = current_thread()->ith_knote;
+       if ((kn != ITH_KNOTE_PSEUDO) && (((option & MACH_RCV_GUARDED_DESC) == 0) ||
+           (current_task() == kernel_task))) {
+#if DEVELOPMENT || DEBUG
+               if (current_task() != kernel_task) {
+                       /*
+                        * Simulated crash needed for debugging, notifies the receiver to opt into receiving
+                        * guarded descriptors.
+                        */
+                       mach_port_guard_exception(current_thread()->ith_receiver_name, 0, 0, kGUARD_EXC_RCV_GUARDED_DESC);
+               }
 #endif
+               KDBG(MACHDBG_CODE(DBG_MACH_IPC, MACH_IPC_DESTROY_GUARDED_DESC), current_thread()->ith_receiver_name,
+                   VM_KERNEL_ADDRPERM(port), disp, guard_flags);
+               ipc_object_destroy(ip_to_object(port), disp);
+               mach_msg_legacy_port_descriptor_t *user_dsc = (typeof(user_dsc))dest_dsc;
+               user_dsc--;         // point to the start of this port descriptor
+               bzero((void *)user_dsc, sizeof(*user_dsc));
+               user_dsc->name = name;
+               user_dsc->disposition = disp;
+               user_dsc->type = MACH_MSG_PORT_DESCRIPTOR;
+               dest_dsc = (typeof(dest_dsc))user_dsc;
+       } else {
+               *mr |= ipc_kmsg_copyout_object(space,
+                   ip_to_object(port), disp, &context, &guard_flags, &name);
+
+               if (!is_64bit) {
+                       mach_msg_guarded_port_descriptor32_t *user_dsc = (typeof(user_dsc))dest_dsc;
+                       user_dsc--;         // point to the start of this port descriptor
+                       bzero((void *)user_dsc, sizeof(*user_dsc));
+                       user_dsc->name = name;
+                       user_dsc->flags = guard_flags;
+                       user_dsc->disposition = disp;
+                       user_dsc->type = MACH_MSG_GUARDED_PORT_DESCRIPTOR;
+                       user_dsc->context = CAST_DOWN_EXPLICIT(uint32_t, context);
+                       dest_dsc = (typeof(dest_dsc))user_dsc;
+               } else {
+                       mach_msg_guarded_port_descriptor64_t *user_dsc = (typeof(user_dsc))dest_dsc;
+                       user_dsc--;         // point to the start of this port descriptor
+                       bzero((void *)user_dsc, sizeof(*user_dsc));
+                       user_dsc->name = name;
+                       user_dsc->flags = guard_flags;
+                       user_dsc->disposition = disp;
+                       user_dsc->type = MACH_MSG_GUARDED_PORT_DESCRIPTOR;
+                       user_dsc->context = context;
+                       dest_dsc = (typeof(dest_dsc))user_dsc;
+               }
+       }
 
-        if (copy_options == MACH_MSG_VIRTUAL_COPY) {
-            /*
-             * Dynamically allocate the region
-             */
-            vm_tag_t tag;
-           if (vm_kernel_map_is_kernel(map)) tag = VM_KERN_MEMORY_IPC;
-           else                              tag = VM_MEMORY_MACH_MSG;
-
-            kern_return_t kr;
-            if ((kr = mach_vm_allocate_kernel(map, &rcv_addr,
-                            (mach_vm_size_t)names_length,
-                            VM_FLAGS_ANYWHERE, tag)) != KERN_SUCCESS) {
-                ipc_kmsg_clean_body(kmsg, 1, (mach_msg_descriptor_t *)dsc);
-                rcv_addr = 0;
-
-                if (kr == KERN_RESOURCE_SHORTAGE){
-                    *mr |= MACH_MSG_VM_KERNEL;
-                } else {
-                    *mr |= MACH_MSG_VM_SPACE;
-                }
-            }
-        }
-
-        /*
-         * Handle the port rights and copy out the names
-         * for those rights out to user-space.
-         */
-        if (rcv_addr != 0) {
-            mach_port_t *objects = (mach_port_t *) dsc->address;
-            mach_port_name_t *names = (mach_port_name_t *) dsc->address;
-
-            /* copyout port rights carried in the message */
-
-            for ( i = 0; i < count ; i++) {
-                ipc_object_t object = (ipc_object_t)objects[i];
-
-                *mr |= ipc_kmsg_copyout_object(space, object,
-                        disp, &names[i]);
-            }
-
-            /* copyout to memory allocated above */
-            void *data = dsc->address;
-            if (copyoutmap(map, data, rcv_addr, names_length) != KERN_SUCCESS)
-                *mr |= MACH_MSG_VM_SPACE;
-            kfree(data, ports_length);
-        }
-    } else {
-        rcv_addr = 0;
-    }
-
-    /*
-     * Now update the descriptor based on the information
-     * calculated above.
-     */
-    if(current_task() == kernel_task) {
-        mach_msg_ool_ports_descriptor_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
-        user_ool_dsc--;
-        bzero((void *)user_ool_dsc, sizeof(*user_ool_dsc));
-
-        user_ool_dsc->address = (void *)(uintptr_t)rcv_addr;
-        user_ool_dsc->deallocate = (copy_options == MACH_MSG_VIRTUAL_COPY) ?
-            TRUE : FALSE;
-        user_ool_dsc->copy = copy_options;
-        user_ool_dsc->disposition = disp;
-        user_ool_dsc->type = MACH_MSG_OOL_PORTS_DESCRIPTOR;
-        user_ool_dsc->count = count;
-
-        user_dsc = (typeof(user_dsc))user_ool_dsc;
-    } if (is_64bit) {
-        mach_msg_ool_ports_descriptor64_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
-        user_ool_dsc--;
-        bzero((void *)user_ool_dsc, sizeof(*user_ool_dsc));
-
-        user_ool_dsc->address = rcv_addr;
-        user_ool_dsc->deallocate = (copy_options == MACH_MSG_VIRTUAL_COPY) ?
-            TRUE : FALSE;
-        user_ool_dsc->copy = copy_options;
-        user_ool_dsc->disposition = disp;
-        user_ool_dsc->type = MACH_MSG_OOL_PORTS_DESCRIPTOR;
-        user_ool_dsc->count = count;
-
-        user_dsc = (typeof(user_dsc))user_ool_dsc;
-    } else {
-        mach_msg_ool_ports_descriptor32_t *user_ool_dsc = (typeof(user_ool_dsc))user_dsc;
-        user_ool_dsc--;
-        bzero((void *)user_ool_dsc, sizeof(*user_ool_dsc));
-
-        user_ool_dsc->address = CAST_DOWN_EXPLICIT(uint32_t, rcv_addr);
-        user_ool_dsc->count = count;
-        user_ool_dsc->deallocate = (copy_options == MACH_MSG_VIRTUAL_COPY) ?
-            TRUE : FALSE;
-        user_ool_dsc->copy = copy_options;
-        user_ool_dsc->disposition = disp;
-        user_ool_dsc->type = MACH_MSG_OOL_PORTS_DESCRIPTOR;
-
-        user_dsc = (typeof(user_dsc))user_ool_dsc;
-    }
-    return user_dsc;
+       return (mach_msg_descriptor_t *)dest_dsc;
 }
 
 /*
@@ -4279,67 +4964,70 @@ ipc_kmsg_copyout_ool_ports_descriptor(mach_msg_ool_ports_descriptor_t *dsc,
 
 mach_msg_return_t
 ipc_kmsg_copyout_body(
-       ipc_kmsg_t              kmsg,
-       ipc_space_t             space,
-       vm_map_t                map,
-       mach_msg_body_t         *slist)
+       ipc_kmsg_t              kmsg,
+       ipc_space_t             space,
+       vm_map_t                map,
+       mach_msg_option_t       option,
+       mach_msg_body_t         *slist)
 {
-    mach_msg_body_t            *body;
-    mach_msg_descriptor_t      *kern_dsc, *user_dsc;
-    mach_msg_descriptor_t      *saddr;
-    mach_msg_type_number_t     dsc_count, sdsc_count;
-    int i;
-    mach_msg_return_t          mr = MACH_MSG_SUCCESS;
-    boolean_t                  is_task_64bit = (map->max_offset > VM_MAX_ADDRESS);
-
-    body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
-    dsc_count = body->msgh_descriptor_count;
-    kern_dsc = (mach_msg_descriptor_t *) (body + 1);
-    /* Point user_dsc just after the end of all the descriptors */
-    user_dsc = &kern_dsc[dsc_count];
-
-    /* Do scatter list setup */
-    if (slist != MACH_MSG_BODY_NULL) {
-    panic("Scatter lists disabled");
-       saddr = (mach_msg_descriptor_t *) (slist + 1);
-       sdsc_count = slist->msgh_descriptor_count;
-    }
-    else {
-       saddr = MACH_MSG_DESCRIPTOR_NULL;
-       sdsc_count = 0;
-    }
-
-    /* Now process the descriptors */
-    for (i = dsc_count-1; i >= 0; i--) {
-        switch (kern_dsc[i].type.type) {
-
-            case MACH_MSG_PORT_DESCRIPTOR: 
-                user_dsc = ipc_kmsg_copyout_port_descriptor(&kern_dsc[i], user_dsc, space, &mr);
-                break;
-            case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
-            case MACH_MSG_OOL_DESCRIPTOR : 
-                user_dsc = ipc_kmsg_copyout_ool_descriptor(
-                        (mach_msg_ool_descriptor_t *)&kern_dsc[i], user_dsc, is_task_64bit, map, &mr);
-                break;
-            case MACH_MSG_OOL_PORTS_DESCRIPTOR : 
-                user_dsc = ipc_kmsg_copyout_ool_ports_descriptor(
-                        (mach_msg_ool_ports_descriptor_t *)&kern_dsc[i], user_dsc, is_task_64bit, map, space, kmsg, &mr);
-                break;
-            default : {
-                          panic("untyped IPC copyout body: invalid message descriptor");
-                      }
-        }
-    }
-
-    if(user_dsc != kern_dsc) {
-        vm_offset_t dsc_adjust = (vm_offset_t)user_dsc - (vm_offset_t)kern_dsc;
-        memmove((char *)((vm_offset_t)kmsg->ikm_header + dsc_adjust), kmsg->ikm_header, sizeof(mach_msg_base_t));
-        kmsg->ikm_header = (mach_msg_header_t *)((vm_offset_t)kmsg->ikm_header + dsc_adjust);
-        /* Update the message size for the smaller user representation */
-        kmsg->ikm_header->msgh_size -= (mach_msg_size_t)dsc_adjust;
-    }
-
-    return mr;
+       mach_msg_body_t             *body;
+       mach_msg_descriptor_t       *kern_dsc, *user_dsc;
+       mach_msg_descriptor_t       *saddr;
+       mach_msg_type_number_t      dsc_count, sdsc_count;
+       int i;
+       mach_msg_return_t           mr = MACH_MSG_SUCCESS;
+       boolean_t                   is_task_64bit = (map->max_offset > VM_MAX_ADDRESS);
+
+       body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
+       dsc_count = body->msgh_descriptor_count;
+       kern_dsc = (mach_msg_descriptor_t *) (body + 1);
+       /* Point user_dsc just after the end of all the descriptors */
+       user_dsc = &kern_dsc[dsc_count];
+
+       /* Do scatter list setup */
+       if (slist != MACH_MSG_BODY_NULL) {
+               panic("Scatter lists disabled");
+               saddr = (mach_msg_descriptor_t *) (slist + 1);
+               sdsc_count = slist->msgh_descriptor_count;
+       } else {
+               saddr = MACH_MSG_DESCRIPTOR_NULL;
+               sdsc_count = 0;
+       }
+
+       /* Now process the descriptors */
+       for (i = dsc_count - 1; i >= 0; i--) {
+               switch (kern_dsc[i].type.type) {
+               case MACH_MSG_PORT_DESCRIPTOR:
+                       user_dsc = ipc_kmsg_copyout_port_descriptor(&kern_dsc[i], user_dsc, space, &mr);
+                       break;
+               case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
+               case MACH_MSG_OOL_DESCRIPTOR:
+                       user_dsc = ipc_kmsg_copyout_ool_descriptor(
+                               (mach_msg_ool_descriptor_t *)&kern_dsc[i], user_dsc, is_task_64bit, map, &mr);
+                       break;
+               case MACH_MSG_OOL_PORTS_DESCRIPTOR:
+                       user_dsc = ipc_kmsg_copyout_ool_ports_descriptor(
+                               (mach_msg_ool_ports_descriptor_t *)&kern_dsc[i], user_dsc, is_task_64bit, map, space, kmsg, &mr);
+                       break;
+               case MACH_MSG_GUARDED_PORT_DESCRIPTOR:
+                       user_dsc = ipc_kmsg_copyout_guarded_port_descriptor(
+                               (mach_msg_guarded_port_descriptor_t *)&kern_dsc[i], user_dsc, is_task_64bit, kmsg, space, option, &mr);
+                       break;
+               default: {
+                       panic("untyped IPC copyout body: invalid message descriptor");
+               }
+               }
+       }
+
+       if (user_dsc != kern_dsc) {
+               vm_offset_t dsc_adjust = (vm_offset_t)user_dsc - (vm_offset_t)kern_dsc;
+               memmove((char *)((vm_offset_t)kmsg->ikm_header + dsc_adjust), kmsg->ikm_header, sizeof(mach_msg_base_t));
+               kmsg->ikm_header = (mach_msg_header_t *)((vm_offset_t)kmsg->ikm_header + dsc_adjust);
+               /* Update the message size for the smaller user representation */
+               kmsg->ikm_header->msgh_size -= (mach_msg_size_t)dsc_adjust;
+       }
+
+       return mr;
 }
 
 /*
@@ -4357,45 +5045,46 @@ ipc_kmsg_copyout_body(
 
 mach_msg_size_t
 ipc_kmsg_copyout_size(
-       ipc_kmsg_t              kmsg,
-       vm_map_t                map)
+       ipc_kmsg_t              kmsg,
+       vm_map_t                map)
 {
-    mach_msg_size_t            send_size;
+       mach_msg_size_t             send_size;
 
-    send_size = kmsg->ikm_header->msgh_size;
+       send_size = kmsg->ikm_header->msgh_size;
 
-    boolean_t is_task_64bit = (map->max_offset > VM_MAX_ADDRESS);
+       boolean_t is_task_64bit = (map->max_offset > VM_MAX_ADDRESS);
 
 #if defined(__LP64__)
        send_size -= LEGACY_HEADER_SIZE_DELTA;
 #endif
 
-    if (kmsg->ikm_header->msgh_bits & MACH_MSGH_BITS_COMPLEX) {
-
-        mach_msg_body_t *body;
-        mach_msg_descriptor_t *saddr, *eaddr;
-
-        body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
-        saddr = (mach_msg_descriptor_t *) (body + 1);
-        eaddr = saddr + body->msgh_descriptor_count;
-
-        for ( ; saddr < eaddr; saddr++ ) {
-            switch (saddr->type.type) {
-                case MACH_MSG_OOL_DESCRIPTOR:
-                case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
-                case MACH_MSG_OOL_PORTS_DESCRIPTOR:
-                    if(!is_task_64bit)
-                        send_size -= DESC_SIZE_ADJUSTMENT;
-                    break;
-                case MACH_MSG_PORT_DESCRIPTOR:
-                    send_size -= DESC_SIZE_ADJUSTMENT;
-                    break;
-                default:
-                    break;
-            }
-        }
-    }
-    return send_size;
+       if (kmsg->ikm_header->msgh_bits & MACH_MSGH_BITS_COMPLEX) {
+               mach_msg_body_t *body;
+               mach_msg_descriptor_t *saddr, *eaddr;
+
+               body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
+               saddr = (mach_msg_descriptor_t *) (body + 1);
+               eaddr = saddr + body->msgh_descriptor_count;
+
+               for (; saddr < eaddr; saddr++) {
+                       switch (saddr->type.type) {
+                       case MACH_MSG_OOL_DESCRIPTOR:
+                       case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
+                       case MACH_MSG_OOL_PORTS_DESCRIPTOR:
+                       case MACH_MSG_GUARDED_PORT_DESCRIPTOR:
+                               if (!is_task_64bit) {
+                                       send_size -= DESC_SIZE_ADJUSTMENT;
+                               }
+                               break;
+                       case MACH_MSG_PORT_DESCRIPTOR:
+                               send_size -= DESC_SIZE_ADJUSTMENT;
+                               break;
+                       default:
+                               break;
+                       }
+               }
+       }
+       return send_size;
 }
 
 /*
@@ -4416,11 +5105,11 @@ ipc_kmsg_copyout_size(
 
 mach_msg_return_t
 ipc_kmsg_copyout(
-       ipc_kmsg_t              kmsg,
-       ipc_space_t             space,
-       vm_map_t                map,
-       mach_msg_body_t         *slist,
-        mach_msg_option_t      option)
+       ipc_kmsg_t              kmsg,
+       ipc_space_t             space,
+       vm_map_t                map,
+       mach_msg_body_t         *slist,
+       mach_msg_option_t      option)
 {
        mach_msg_return_t mr;
 
@@ -4430,10 +5119,11 @@ ipc_kmsg_copyout(
        }
 
        if (kmsg->ikm_header->msgh_bits & MACH_MSGH_BITS_COMPLEX) {
-               mr = ipc_kmsg_copyout_body(kmsg, space, map, slist);
+               mr = ipc_kmsg_copyout_body(kmsg, space, map, option, slist);
 
-               if (mr != MACH_MSG_SUCCESS)
+               if (mr != MACH_MSG_SUCCESS) {
                        mr |= MACH_RCV_BODY_ERROR;
+               }
        }
 
        return mr;
@@ -4461,15 +5151,15 @@ ipc_kmsg_copyout(
 
 mach_msg_return_t
 ipc_kmsg_copyout_pseudo(
-       ipc_kmsg_t              kmsg,
-       ipc_space_t             space,
-       vm_map_t                map,
-       mach_msg_body_t         *slist)
+       ipc_kmsg_t              kmsg,
+       ipc_space_t             space,
+       vm_map_t                map,
+       mach_msg_body_t         *slist)
 {
        mach_msg_bits_t mbits = kmsg->ikm_header->msgh_bits;
-       ipc_object_t dest = (ipc_object_t) kmsg->ikm_header->msgh_remote_port;
-       ipc_object_t reply = (ipc_object_t) kmsg->ikm_header->msgh_local_port;
-       ipc_object_t voucher = (ipc_object_t) kmsg->ikm_voucher;
+       ipc_object_t dest = ip_to_object(kmsg->ikm_header->msgh_remote_port);
+       ipc_object_t reply = ip_to_object(kmsg->ikm_header->msgh_local_port);
+       ipc_object_t voucher = ip_to_object(kmsg->ikm_voucher);
        mach_msg_type_name_t dest_type = MACH_MSGH_BITS_REMOTE(mbits);
        mach_msg_type_name_t reply_type = MACH_MSGH_BITS_LOCAL(mbits);
        mach_msg_type_name_t voucher_type = MACH_MSGH_BITS_VOUCHER(mbits);
@@ -4494,8 +5184,8 @@ ipc_kmsg_copyout_pseudo(
        ipc_importance_assert_clean(kmsg);
 #endif
 
-       mr = (ipc_kmsg_copyout_object(space, dest, dest_type, &dest_name) |
-             ipc_kmsg_copyout_object(space, reply, reply_type, &reply_name));
+       mr = (ipc_kmsg_copyout_object(space, dest, dest_type, NULL, NULL, &dest_name) |
+           ipc_kmsg_copyout_object(space, reply, reply_type, NULL, NULL, &reply_name));
 
        kmsg->ikm_header->msgh_bits = mbits & MACH_MSGH_BITS_USER;
        kmsg->ikm_header->msgh_remote_port = CAST_MACH_NAME_TO_PORT(dest_name);
@@ -4505,12 +5195,12 @@ ipc_kmsg_copyout_pseudo(
                assert(voucher_type == MACH_MSG_TYPE_MOVE_SEND);
 
                kmsg->ikm_voucher = IP_NULL;
-               mr |= ipc_kmsg_copyout_object(space, voucher, voucher_type, &voucher_name);
+               mr |= ipc_kmsg_copyout_object(space, voucher, voucher_type, NULL, NULL, &voucher_name);
                kmsg->ikm_header->msgh_voucher_port = voucher_name;
        }
-               
+
        if (mbits & MACH_MSGH_BITS_COMPLEX) {
-               mr |= ipc_kmsg_copyout_body(kmsg, space, map, slist);
+               mr |= ipc_kmsg_copyout_body(kmsg, space, map, 0, slist);
        }
 
        return mr;
@@ -4527,8 +5217,8 @@ ipc_kmsg_copyout_pseudo(
 
 void
 ipc_kmsg_copyout_dest(
-       ipc_kmsg_t      kmsg,
-       ipc_space_t     space)
+       ipc_kmsg_t      kmsg,
+       ipc_space_t     space)
 {
        mach_msg_bits_t mbits;
        ipc_object_t dest;
@@ -4540,9 +5230,9 @@ ipc_kmsg_copyout_dest(
        mach_port_name_t dest_name, reply_name, voucher_name;
 
        mbits = kmsg->ikm_header->msgh_bits;
-       dest = (ipc_object_t) kmsg->ikm_header->msgh_remote_port;
-       reply = (ipc_object_t) kmsg->ikm_header->msgh_local_port;
-       voucher = (ipc_object_t) kmsg->ikm_voucher;
+       dest = ip_to_object(kmsg->ikm_header->msgh_remote_port);
+       reply = ip_to_object(kmsg->ikm_header->msgh_local_port);
+       voucher = ip_to_object(kmsg->ikm_voucher);
        voucher_name = kmsg->ikm_header->msgh_voucher_port;
        dest_type = MACH_MSGH_BITS_REMOTE(mbits);
        reply_type = MACH_MSGH_BITS_LOCAL(mbits);
@@ -4565,19 +5255,20 @@ ipc_kmsg_copyout_dest(
        if (IO_VALID(reply)) {
                ipc_object_destroy(reply, reply_type);
                reply_name = MACH_PORT_NULL;
-       } else
+       } else {
                reply_name = CAST_MACH_PORT_TO_NAME(reply);
+       }
 
        if (IO_VALID(voucher)) {
                assert(voucher_type == MACH_MSG_TYPE_MOVE_SEND);
 
                kmsg->ikm_voucher = IP_NULL;
-               ipc_object_destroy((ipc_object_t)voucher, voucher_type);
+               ipc_object_destroy(voucher, voucher_type);
                voucher_name = MACH_PORT_NULL;
        }
 
        kmsg->ikm_header->msgh_bits = MACH_MSGH_BITS_SET(reply_type, dest_type,
-                                                        voucher_type, mbits);
+           voucher_type, mbits);
        kmsg->ikm_header->msgh_local_port = CAST_MACH_NAME_TO_PORT(dest_name);
        kmsg->ikm_header->msgh_remote_port = CAST_MACH_NAME_TO_PORT(reply_name);
        kmsg->ikm_header->msgh_voucher_port = voucher_name;
@@ -4586,8 +5277,8 @@ ipc_kmsg_copyout_dest(
                mach_msg_body_t *body;
 
                body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
-               ipc_kmsg_clean_body(kmsg, body->msgh_descriptor_count, 
-                                   (mach_msg_descriptor_t *)(body + 1));
+               ipc_kmsg_clean_body(kmsg, body->msgh_descriptor_count,
+                   (mach_msg_descriptor_t *)(body + 1));
        }
 }
 
@@ -4606,17 +5297,17 @@ ipc_kmsg_copyout_dest(
 
 void
 ipc_kmsg_copyout_to_kernel(
-       ipc_kmsg_t      kmsg,
-       ipc_space_t     space)
+       ipc_kmsg_t      kmsg,
+       ipc_space_t     space)
 {
        ipc_object_t dest;
-       ipc_object_t reply;
+       mach_port_t reply;
        mach_msg_type_name_t dest_type;
        mach_msg_type_name_t reply_type;
-       mach_port_name_t dest_name, reply_name;
+       mach_port_name_t dest_name;
 
-       dest = (ipc_object_t) kmsg->ikm_header->msgh_remote_port;
-       reply = (ipc_object_t) kmsg->ikm_header->msgh_local_port;
+       dest = ip_to_object(kmsg->ikm_header->msgh_remote_port);
+       reply = kmsg->ikm_header->msgh_local_port;
        dest_type = MACH_MSGH_BITS_REMOTE(kmsg->ikm_header->msgh_bits);
        reply_type = MACH_MSGH_BITS_LOCAL(kmsg->ikm_header->msgh_bits);
 
@@ -4632,29 +5323,50 @@ ipc_kmsg_copyout_to_kernel(
                dest_name = MACH_PORT_DEAD;
        }
 
-       reply_name = CAST_MACH_PORT_TO_NAME(reply);
+       /*
+        * While MIG kernel users don't receive vouchers, the
+        * msgh_voucher_port field is intended to be round-tripped through the
+        * kernel if there is no voucher disposition set. Here we check for a
+        * non-zero voucher disposition, and consume the voucher send right as
+        * there is no possible way to specify MACH_RCV_VOUCHER semantics.
+        */
+       mach_msg_type_name_t voucher_type;
+       voucher_type = MACH_MSGH_BITS_VOUCHER(kmsg->ikm_header->msgh_bits);
+       if (voucher_type != MACH_MSGH_BITS_ZERO) {
+               assert(voucher_type == MACH_MSG_TYPE_MOVE_SEND);
+               /*
+                * someone managed to send this kernel routine a message with
+                * a voucher in it. Cleanup the reference in
+                * kmsg->ikm_voucher.
+                */
+               if (IP_VALID(kmsg->ikm_voucher)) {
+                       ipc_port_release_send(kmsg->ikm_voucher);
+               }
+               kmsg->ikm_voucher = IP_NULL;
+               kmsg->ikm_header->msgh_voucher_port = 0;
+       }
 
        kmsg->ikm_header->msgh_bits =
-               (MACH_MSGH_BITS_OTHER(kmsg->ikm_header->msgh_bits) |
-                                       MACH_MSGH_BITS(reply_type, dest_type));
+           (MACH_MSGH_BITS_OTHER(kmsg->ikm_header->msgh_bits) |
+           MACH_MSGH_BITS(reply_type, dest_type));
        kmsg->ikm_header->msgh_local_port =  CAST_MACH_NAME_TO_PORT(dest_name);
-       kmsg->ikm_header->msgh_remote_port = CAST_MACH_NAME_TO_PORT(reply_name);
+       kmsg->ikm_header->msgh_remote_port = reply;
 }
 
 #if IKM_SUPPORT_LEGACY
 void
 ipc_kmsg_copyout_to_kernel_legacy(
-       ipc_kmsg_t      kmsg,
-       ipc_space_t     space)
+       ipc_kmsg_t      kmsg,
+       ipc_space_t     space)
 {
        ipc_object_t dest;
-       ipc_object_t reply;
+       mach_port_t  reply;
        mach_msg_type_name_t dest_type;
        mach_msg_type_name_t reply_type;
-       mach_port_name_t dest_name, reply_name;
+       mach_port_name_t dest_name;
 
-       dest = (ipc_object_t) kmsg->ikm_header->msgh_remote_port;
-       reply = (ipc_object_t) kmsg->ikm_header->msgh_local_port;
+       dest = ip_to_object(kmsg->ikm_header->msgh_remote_port);
+       reply = kmsg->ikm_header->msgh_local_port;
        dest_type = MACH_MSGH_BITS_REMOTE(kmsg->ikm_header->msgh_bits);
        reply_type = MACH_MSGH_BITS_LOCAL(kmsg->ikm_header->msgh_bits);
 
@@ -4670,93 +5382,117 @@ ipc_kmsg_copyout_to_kernel_legacy(
                dest_name = MACH_PORT_DEAD;
        }
 
-       reply_name = CAST_MACH_PORT_TO_NAME(reply);
+       mach_msg_type_name_t voucher_type;
+       voucher_type = MACH_MSGH_BITS_VOUCHER(kmsg->ikm_header->msgh_bits);
+       if (voucher_type != MACH_MSGH_BITS_ZERO) {
+               assert(voucher_type == MACH_MSG_TYPE_MOVE_SEND);
+               assert(IP_VALID(kmsg->ikm_voucher));
+               /*
+                * someone managed to send this kernel routine a message with
+                * a voucher in it. Cleanup the reference in
+                * kmsg->ikm_voucher.
+                */
+               ipc_port_release_send(kmsg->ikm_voucher);
+               kmsg->ikm_voucher = IP_NULL;
+               kmsg->ikm_header->msgh_voucher_port = 0;
+       }
 
        kmsg->ikm_header->msgh_bits =
-               (MACH_MSGH_BITS_OTHER(kmsg->ikm_header->msgh_bits) |
-                                       MACH_MSGH_BITS(reply_type, dest_type));
+           (MACH_MSGH_BITS_OTHER(kmsg->ikm_header->msgh_bits) |
+           MACH_MSGH_BITS(reply_type, dest_type));
        kmsg->ikm_header->msgh_local_port =  CAST_MACH_NAME_TO_PORT(dest_name);
-       kmsg->ikm_header->msgh_remote_port = CAST_MACH_NAME_TO_PORT(reply_name);
+       kmsg->ikm_header->msgh_remote_port = reply;
+
+       mach_msg_descriptor_t *saddr;
+       mach_msg_legacy_descriptor_t *daddr;
+       mach_msg_type_number_t i, count = ((mach_msg_base_t *)kmsg->ikm_header)->body.msgh_descriptor_count;
+       saddr = (mach_msg_descriptor_t *) (((mach_msg_base_t *)kmsg->ikm_header) + 1);
+       saddr = &saddr[count - 1];
+       daddr = (mach_msg_legacy_descriptor_t *)&saddr[count];
+       daddr--;
+
+       vm_offset_t dsc_adjust = 0;
+
+       for (i = 0; i < count; i++, saddr--, daddr--) {
+               switch (saddr->type.type) {
+               case MACH_MSG_PORT_DESCRIPTOR: {
+                       mach_msg_port_descriptor_t *dsc = &saddr->port;
+                       mach_msg_legacy_port_descriptor_t *dest_dsc = &daddr->port;
+
+                       mach_port_t name = dsc->name;
+                       mach_msg_type_name_t disposition = dsc->disposition;
+
+                       dest_dsc->name = CAST_MACH_PORT_TO_NAME(name);
+                       dest_dsc->disposition = disposition;
+                       dest_dsc->type = MACH_MSG_PORT_DESCRIPTOR;
+                       break;
+               }
+               case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
+               case MACH_MSG_OOL_DESCRIPTOR: {
+                       /* The sender should supply ready-made memory, i.e. a vm_map_copy_t
+                        * so we don't need to do anything special. */
+
+                       mach_msg_ool_descriptor_t       *source_dsc = (typeof(source_dsc)) & saddr->out_of_line;
+
+                       mach_msg_ool_descriptor32_t *dest_dsc = &daddr->out_of_line32;
+
+                       vm_offset_t                         address = (vm_offset_t)source_dsc->address;
+                       vm_size_t                       size = source_dsc->size;
+                       boolean_t                       deallocate = source_dsc->deallocate;
+                       mach_msg_copy_options_t         copy = source_dsc->copy;
+                       mach_msg_descriptor_type_t  type = source_dsc->type;
 
-    mach_msg_descriptor_t *saddr;
-    mach_msg_legacy_descriptor_t *daddr;
-    mach_msg_type_number_t i, count = ((mach_msg_base_t *)kmsg->ikm_header)->body.msgh_descriptor_count;
-    saddr = (mach_msg_descriptor_t *) (((mach_msg_base_t *)kmsg->ikm_header) + 1);
-    saddr = &saddr[count-1];
-    daddr = (mach_msg_legacy_descriptor_t *)&saddr[count];
-    daddr--;
-
-    vm_offset_t dsc_adjust = 0;
-
-    for (i = 0; i < count; i++, saddr--, daddr--) {
-    switch (saddr->type.type) {
-        case MACH_MSG_PORT_DESCRIPTOR: {
-        mach_msg_port_descriptor_t *dsc = &saddr->port;
-        mach_msg_legacy_port_descriptor_t *dest_dsc = &daddr->port;
-
-        mach_port_t name = dsc->name;
-        mach_msg_type_name_t disposition = dsc->disposition;
-
-        dest_dsc->name = CAST_MACH_PORT_TO_NAME(name);
-        dest_dsc->disposition = disposition;
-        dest_dsc->type = MACH_MSG_PORT_DESCRIPTOR;
-        break;
-        }
-    case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
-    case MACH_MSG_OOL_DESCRIPTOR: {
-        /* The sender should supply ready-made memory, i.e. a vm_map_copy_t
-         * so we don't need to do anything special. */
-
-        mach_msg_ool_descriptor_t      *source_dsc = (typeof(source_dsc))&saddr->out_of_line;
-
-            mach_msg_ool_descriptor32_t        *dest_dsc = &daddr->out_of_line32;
-
-        vm_offset_t                        address = (vm_offset_t)source_dsc->address;
-        vm_size_t                      size = source_dsc->size;
-        boolean_t                      deallocate = source_dsc->deallocate;
-        mach_msg_copy_options_t                copy = source_dsc->copy;
-        mach_msg_descriptor_type_t  type = source_dsc->type;
-
-        dest_dsc->address = address;
-        dest_dsc->size = size;
-        dest_dsc->deallocate = deallocate;
-        dest_dsc->copy = copy;
-        dest_dsc->type = type;
-        break;
-        }
-    case MACH_MSG_OOL_PORTS_DESCRIPTOR: {
-        mach_msg_ool_ports_descriptor_t        *source_dsc = (typeof(source_dsc))&saddr->ool_ports;
-
-            mach_msg_ool_ports_descriptor32_t  *dest_dsc = &daddr->ool_ports32;
-
-        vm_offset_t                        address = (vm_offset_t)source_dsc->address;
-        vm_size_t                      port_count = source_dsc->count;
-        boolean_t                      deallocate = source_dsc->deallocate;
-        mach_msg_copy_options_t                copy = source_dsc->copy;
-        mach_msg_descriptor_type_t  type = source_dsc->type;
-
-        dest_dsc->address = address;
-        dest_dsc->count = port_count;
-        dest_dsc->deallocate = deallocate;
-        dest_dsc->copy = copy;
-        dest_dsc->type = type;
-        break;
-        }
-        default: {
-#if    MACH_ASSERT
-        panic("ipc_kmsg_copyin_from_kernel:  bad descriptor");
-#endif /* MACH_ASSERT */
-                 }
-    }
-    }
-
-    if(count) {
-        dsc_adjust = 4*count;
-        memmove((char *)((vm_offset_t)kmsg->ikm_header + dsc_adjust), kmsg->ikm_header, sizeof(mach_msg_base_t));
-        kmsg->ikm_header = (mach_msg_header_t *)((vm_offset_t)kmsg->ikm_header + dsc_adjust);
-        /* Update the message size for the smaller user representation */
-        kmsg->ikm_header->msgh_size -= dsc_adjust;
-    }
+                       dest_dsc->address = address;
+                       dest_dsc->size = size;
+                       dest_dsc->deallocate = deallocate;
+                       dest_dsc->copy = copy;
+                       dest_dsc->type = type;
+                       break;
+               }
+               case MACH_MSG_OOL_PORTS_DESCRIPTOR: {
+                       mach_msg_ool_ports_descriptor_t         *source_dsc = (typeof(source_dsc)) & saddr->ool_ports;
+
+                       mach_msg_ool_ports_descriptor32_t   *dest_dsc = &daddr->ool_ports32;
+
+                       vm_offset_t                         address = (vm_offset_t)source_dsc->address;
+                       vm_size_t                       port_count = source_dsc->count;
+                       boolean_t                       deallocate = source_dsc->deallocate;
+                       mach_msg_copy_options_t         copy = source_dsc->copy;
+                       mach_msg_descriptor_type_t  type = source_dsc->type;
+
+                       dest_dsc->address = address;
+                       dest_dsc->count = port_count;
+                       dest_dsc->deallocate = deallocate;
+                       dest_dsc->copy = copy;
+                       dest_dsc->type = type;
+                       break;
+               }
+               case MACH_MSG_GUARDED_PORT_DESCRIPTOR: {
+                       mach_msg_guarded_port_descriptor_t *source_dsc = (typeof(source_dsc)) & saddr->guarded_port;
+                       mach_msg_guarded_port_descriptor32_t *dest_dsc = &daddr->guarded_port32;
+
+                       dest_dsc->name = CAST_MACH_PORT_TO_NAME(source_dsc->name);
+                       dest_dsc->disposition = source_dsc->disposition;
+                       dest_dsc->flags = 0;
+                       dest_dsc->type = MACH_MSG_GUARDED_PORT_DESCRIPTOR;
+                       dest_dsc->context = 0;
+                       break;
+               }
+               default: {
+#if     MACH_ASSERT
+                       panic("ipc_kmsg_copyout_to_kernel_legacy: bad descriptor");
+#endif  /* MACH_ASSERT */
+               }
+               }
+       }
+
+       if (count) {
+               dsc_adjust = 4 * count;
+               memmove((char *)((vm_offset_t)kmsg->ikm_header + dsc_adjust), kmsg->ikm_header, sizeof(mach_msg_base_t));
+               kmsg->ikm_header = (mach_msg_header_t *)((vm_offset_t)kmsg->ikm_header + dsc_adjust);
+               /* Update the message size for the smaller user representation */
+               kmsg->ikm_header->msgh_size -= dsc_adjust;
+       }
 }
 #endif /* IKM_SUPPORT_LEGACY */
 
@@ -4765,7 +5501,7 @@ ipc_kmsg_copyout_to_kernel_legacy(
  * Just sets those parts of the trailer that aren't set up at allocation time.
  */
 static void
-ipc_kmsg_munge_trailer(mach_msg_max_trailer_t *in, void *_out, boolean_t is64bit) 
+ipc_kmsg_munge_trailer(mach_msg_max_trailer_t *in, void *_out, boolean_t is64bit)
 {
        if (is64bit) {
                mach_msg_max_trailer64_t *out = (mach_msg_max_trailer64_t*)_out;
@@ -4784,22 +5520,22 @@ ipc_kmsg_munge_trailer(mach_msg_max_trailer_t *in, void *_out, boolean_t is64bit
 #endif /* __arm64__ */
 
 mach_msg_trailer_size_t
-ipc_kmsg_add_trailer(ipc_kmsg_t kmsg, ipc_space_t space __unused, 
-               mach_msg_option_t option, thread_t thread, 
-               mach_port_seqno_t seqno, boolean_t minimal_trailer,
-               mach_vm_offset_t context)
+ipc_kmsg_add_trailer(ipc_kmsg_t kmsg, ipc_space_t space __unused,
+    mach_msg_option_t option, thread_t thread,
+    mach_port_seqno_t seqno, boolean_t minimal_trailer,
+    mach_vm_offset_t context)
 {
        mach_msg_max_trailer_t *trailer;
 
 #ifdef __arm64__
        mach_msg_max_trailer_t tmp_trailer; /* This accommodates U64, and we'll munge */
        void *real_trailer_out = (void*)(mach_msg_max_trailer_t *)
-               ((vm_offset_t)kmsg->ikm_header +
-                round_msg(kmsg->ikm_header->msgh_size));
+           ((vm_offset_t)kmsg->ikm_header +
+           round_msg(kmsg->ikm_header->msgh_size));
 
-       /* 
+       /*
         * Populate scratch with initial values set up at message allocation time.
-        * After, we reinterpret the space in the message as the right type 
+        * After, we reinterpret the space in the message as the right type
         * of trailer for the address space in question.
         */
        bcopy(real_trailer_out, &tmp_trailer, MAX_TRAILER_SIZE);
@@ -4807,8 +5543,8 @@ ipc_kmsg_add_trailer(ipc_kmsg_t kmsg, ipc_space_t space __unused,
 #else /* __arm64__ */
        (void)thread;
        trailer = (mach_msg_max_trailer_t *)
-               ((vm_offset_t)kmsg->ikm_header +
-                round_msg(kmsg->ikm_header->msgh_size));
+           ((vm_offset_t)kmsg->ikm_header +
+           round_msg(kmsg->ikm_header->msgh_size));
 #endif /* __arm64__ */
 
        if (!(option & MACH_RCV_TRAILER_MASK)) {
@@ -4817,14 +5553,13 @@ ipc_kmsg_add_trailer(ipc_kmsg_t kmsg, ipc_space_t space __unused,
 
        trailer->msgh_seqno = seqno;
        trailer->msgh_context = context;
-       trailer->msgh_trailer_size = REQUESTED_TRAILER_SIZE(thread_is_64bit(thread), option);
+       trailer->msgh_trailer_size = REQUESTED_TRAILER_SIZE(thread_is_64bit_addr(thread), option);
 
-       if (minimal_trailer) { 
+       if (minimal_trailer) {
                goto done;
        }
 
-       if (MACH_RCV_TRAILER_ELEMENTS(option) >= 
-                       MACH_RCV_TRAILER_ELEMENTS(MACH_RCV_TRAILER_AV)){
+       if (GET_RCV_ELEMENTS(option) >= MACH_RCV_TRAILER_AV) {
                trailer->msgh_ad = 0;
        }
 
@@ -4834,14 +5569,23 @@ ipc_kmsg_add_trailer(ipc_kmsg_t kmsg, ipc_space_t space __unused,
         * and a send right to copyout to the receiver.
         */
 
-       if (option & MACH_RCV_TRAILER_ELEMENTS (MACH_RCV_TRAILER_LABELS)) {
+       if (option & MACH_RCV_TRAILER_ELEMENTS(MACH_RCV_TRAILER_LABELS)) {
                trailer->msgh_labels.sender = 0;
        }
 
 done:
 #ifdef __arm64__
-       ipc_kmsg_munge_trailer(trailer, real_trailer_out, thread_is_64bit(thread));
+       ipc_kmsg_munge_trailer(trailer, real_trailer_out, thread_is_64bit_addr(thread));
 #endif /* __arm64__ */
 
        return trailer->msgh_trailer_size;
 }
+
+mach_msg_header_t *
+ipc_kmsg_msg_header(ipc_kmsg_t kmsg)
+{
+       if (NULL == kmsg) {
+               return NULL;
+       }
+       return kmsg->ikm_header;
+}