]> git.saurik.com Git - apple/xnu.git/blobdiff - osfmk/ipc/mach_debug.c
xnu-3789.70.16.tar.gz
[apple/xnu.git] / osfmk / ipc / mach_debug.c
index ead49e1bcb93be27f056b323d7af0557135aa19a..972073a71e512a528ed6888a8b4a7f6b47fbc755 100644 (file)
@@ -1,16 +1,19 @@
 /*
- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
  *
- * @APPLE_LICENSE_HEADER_START@
- * 
- * Copyright (c) 1999-2003 Apple Computer, 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
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * 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
@@ -20,7 +23,7 @@
  * Please see the License for the specific language governing rights and
  * limitations under the License.
  * 
- * @APPLE_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 /*
  * @OSF_COPYRIGHT@
 #include <kern/misc_protos.h>
 #include <vm/vm_map.h>
 #include <vm/vm_kern.h>
+#include <ipc/port.h>
+#include <ipc/ipc_types.h>
 #include <ipc/ipc_space.h>
 #include <ipc/ipc_port.h>
 #include <ipc/ipc_hash.h>
 #include <ipc/ipc_table.h>
 #include <ipc/ipc_right.h>
+
+#include <security/mac_mach_internal.h>
 #endif
 
 /*
  *             KERN_INVALID_RIGHT      Name doesn't denote receive rights.
  */
 
+#if !MACH_IPC_DEBUG
+kern_return_t
+mach_port_get_srights(
+       __unused ipc_space_t            space,
+       __unused mach_port_name_t       name,
+       __unused mach_port_rights_t     *srightsp)
+{
+        return KERN_FAILURE;
+}
+#else
 kern_return_t
 mach_port_get_srights(
        ipc_space_t             space,
        mach_port_name_t        name,
        mach_port_rights_t      *srightsp)
 {
-#if !MACH_IPC_DEBUG
-        return KERN_FAILURE;
-#else
        ipc_port_t port;
        kern_return_t kr;
        mach_port_rights_t srights;
@@ -122,91 +136,9 @@ mach_port_get_srights(
 
        *srightsp = srights;
        return KERN_SUCCESS;
-#endif /* MACH_IPC_DEBUG */
 }
-
-/*
- *     Routine:        host_ipc_hash_info
- *     Purpose:
- *             Return information about the global reverse hash table.
- *     Conditions:
- *             Nothing locked.  Obeys CountInOut protocol.
- *     Returns:
- *             KERN_SUCCESS            Returned information.
- *             KERN_INVALID_HOST       The host is null.
- *             KERN_RESOURCE_SHORTAGE  Couldn't allocate memory.
- */
-
-kern_return_t
-host_ipc_hash_info(
-       host_t                          host,
-       hash_info_bucket_array_t        *infop,
-       mach_msg_type_number_t          *countp)
-{
-#if !MACH_IPC_DEBUG
-        return KERN_FAILURE;
-#else
-       vm_offset_t addr;
-       vm_size_t size;
-       hash_info_bucket_t *info;
-       unsigned int potential, actual;
-       kern_return_t kr;
-
-       if (host == HOST_NULL)
-               return KERN_INVALID_HOST;
-
-       /* start with in-line data */
-
-       info = *infop;
-       potential = *countp;
-
-       for (;;) {
-               actual = ipc_hash_info(info, potential);
-               if (actual <= potential)
-                       break;
-
-               /* allocate more memory */
-
-               if (info != *infop)
-                       kmem_free(ipc_kernel_map, addr, size);
-
-               size = round_page_32(actual * sizeof *info);
-               kr = kmem_alloc_pageable(ipc_kernel_map, &addr, size);
-               if (kr != KERN_SUCCESS)
-                       return KERN_RESOURCE_SHORTAGE;
-
-               info = (hash_info_bucket_t *) addr;
-               potential = size/sizeof *info;
-       }
-
-       if (info == *infop) {
-               /* data fit in-line; nothing to deallocate */
-
-               *countp = actual;
-       } else if (actual == 0) {
-               kmem_free(ipc_kernel_map, addr, size);
-
-               *countp = 0;
-       } else {
-               vm_map_copy_t copy;
-               vm_size_t used;
-
-               used = round_page_32(actual * sizeof *info);
-
-               if (used != size)
-                       kmem_free(ipc_kernel_map, addr + used, size - used);
-
-               kr = vm_map_copyin(ipc_kernel_map, addr, used,
-                                  TRUE, &copy);
-               assert(kr == KERN_SUCCESS);
-
-               *infop = (hash_info_bucket_t *) copy;
-               *countp = actual;
-       }
-
-       return KERN_SUCCESS;
 #endif /* MACH_IPC_DEBUG */
-}
+
 
 /*
  *     Routine:        mach_port_space_info
@@ -221,119 +153,93 @@ host_ipc_hash_info(
  *             KERN_RESOURCE_SHORTAGE  Couldn't allocate memory.
  */
 
+#if !MACH_IPC_DEBUG
+kern_return_t
+mach_port_space_info(
+       __unused ipc_space_t                    space,
+       __unused ipc_info_space_t               *infop,
+       __unused ipc_info_name_array_t  *tablep,
+       __unused mach_msg_type_number_t         *tableCntp,
+       __unused ipc_info_tree_name_array_t *treep,
+       __unused mach_msg_type_number_t         *treeCntp)
+{
+        return KERN_FAILURE;
+}
+#else
 kern_return_t
 mach_port_space_info(
        ipc_space_t                     space,
        ipc_info_space_t                *infop,
        ipc_info_name_array_t           *tablep,
        mach_msg_type_number_t          *tableCntp,
-       ipc_info_tree_name_array_t      *treep,
-       mach_msg_type_number_t          *treeCntp)
+       __unused ipc_info_tree_name_array_t     *treep,
+       __unused mach_msg_type_number_t         *treeCntp)
 {
-#if !MACH_IPC_DEBUG
-        return KERN_FAILURE;
-#else
        ipc_info_name_t *table_info;
-       unsigned int table_potential, table_actual;
        vm_offset_t table_addr;
-       vm_size_t table_size;
-       ipc_info_tree_name_t *tree_info;
-       unsigned int tree_potential, tree_actual;
-       vm_offset_t tree_addr;
-       vm_size_t tree_size;
-       ipc_tree_entry_t tentry;
+       vm_size_t table_size, table_size_needed;
        ipc_entry_t table;
        ipc_entry_num_t tsize;
        mach_port_index_t index;
        kern_return_t kr;
-       ipc_entry_bits_t *capability;
+       vm_map_copy_t copy;
+
 
        if (space == IS_NULL)
                return KERN_INVALID_TASK;
 
+#if !(DEVELOPMENT || DEBUG) && CONFIG_MACF
+       const boolean_t dbg_ok = (mac_task_check_expose_task(kernel_task) == 0);
+#else
+       const boolean_t dbg_ok = TRUE;
+#endif
+
        /* start with in-line memory */
 
-       table_info = *tablep;
-       table_potential = *tableCntp;
-       tree_info = *treep;
-       tree_potential = *treeCntp;
+       table_size = 0;
 
        for (;;) {
                is_read_lock(space);
-               if (!space->is_active) {
+               if (!is_active(space)) {
                        is_read_unlock(space);
-                       if (table_info != *tablep)
+                       if (table_size != 0)
                                kmem_free(ipc_kernel_map,
                                          table_addr, table_size);
-                       if (tree_info != *treep)
-                               kmem_free(ipc_kernel_map,
-                                         tree_addr, tree_size);
                        return KERN_INVALID_TASK;
                }
 
-               table_actual = space->is_table_size;
-               tree_actual = space->is_tree_total;
+               table_size_needed =
+                       vm_map_round_page((space->is_table_size
+                                          * sizeof(ipc_info_name_t)),
+                                         VM_MAP_PAGE_MASK(ipc_kernel_map));
 
-               if ((table_actual <= table_potential) &&
-                   (tree_actual <= tree_potential))
+               if (table_size_needed == table_size)
                        break;
 
                is_read_unlock(space);
 
-               if (table_actual > table_potential) {
-                       if (table_info != *tablep)
-                               kmem_free(ipc_kernel_map,
-                                         table_addr, table_size);
-
-                       table_size = round_page_32(table_actual *
-                                               sizeof *table_info);
-                       kr = kmem_alloc(ipc_kernel_map,
-                                       &table_addr, table_size);
+               if (table_size != table_size_needed) {
+                       if (table_size != 0)
+                               kmem_free(ipc_kernel_map, table_addr, table_size);
+                       kr = kmem_alloc(ipc_kernel_map, &table_addr, table_size_needed, VM_KERN_MEMORY_IPC);
                        if (kr != KERN_SUCCESS) {
-                               if (tree_info != *treep)
-                                       kmem_free(ipc_kernel_map,
-                                                 tree_addr, tree_size);
-
                                return KERN_RESOURCE_SHORTAGE;
                        }
-
-                       table_info = (ipc_info_name_t *) table_addr;
-                       table_potential = table_size/sizeof *table_info;
+                       table_size = table_size_needed;
                }
 
-               if (tree_actual > tree_potential) {
-                       if (tree_info != *treep)
-                               kmem_free(ipc_kernel_map,
-                                         tree_addr, tree_size);
-
-                       tree_size = round_page_32(tree_actual *
-                                              sizeof *tree_info);
-                       kr = kmem_alloc(ipc_kernel_map,
-                                       &tree_addr, tree_size);
-                       if (kr != KERN_SUCCESS) {
-                               if (table_info != *tablep)
-                                       kmem_free(ipc_kernel_map,
-                                                 table_addr, table_size);
-
-                               return KERN_RESOURCE_SHORTAGE;
-                       }
-
-                       tree_info = (ipc_info_tree_name_t *) tree_addr;
-                       tree_potential = tree_size/sizeof *tree_info;
-               }
        }
        /* space is read-locked and active; we have enough wired memory */
 
+       /* get the overall space info */
        infop->iis_genno_mask = MACH_PORT_NGEN(MACH_PORT_DEAD);
        infop->iis_table_size = space->is_table_size;
        infop->iis_table_next = space->is_table_next->its_size;
-       infop->iis_tree_size = space->is_tree_total;
-       infop->iis_tree_small = space->is_tree_small;
-       infop->iis_tree_hash = space->is_tree_hash;
 
+       /* walk the table for this space */
        table = space->is_table;
        tsize = space->is_table_size;
-
+       table_info = (ipc_info_name_array_t)table_addr;
        for (index = 0; index < tsize; index++) {
                ipc_info_name_t *iin = &table_info[index];
                ipc_entry_t entry = &table[index];
@@ -341,125 +247,109 @@ mach_port_space_info(
 
                bits = entry->ie_bits;
                iin->iin_name = MACH_PORT_MAKE(index, IE_BITS_GEN(bits));
-               iin->iin_collision = (bits & IE_BITS_COLLISION) ? TRUE : FALSE;
+               iin->iin_collision = 0;
                iin->iin_type = IE_BITS_TYPE(bits);
-               iin->iin_urefs = IE_BITS_UREFS(bits);
-               iin->iin_object = (vm_offset_t) entry->ie_object;
-               iin->iin_next = entry->ie_next;
-               iin->iin_hash = entry->ie_index;
-       }
-
-       for (tentry = ipc_splay_traverse_start(&space->is_tree), index = 0;
-            tentry != ITE_NULL;
-            tentry = ipc_splay_traverse_next(&space->is_tree, FALSE)) {
-               ipc_info_tree_name_t *iitn = &tree_info[index++];
-               ipc_info_name_t *iin = &iitn->iitn_name;
-               ipc_entry_t entry = &tentry->ite_entry;
-               ipc_entry_bits_t bits = entry->ie_bits;
-
-               assert(IE_BITS_TYPE(bits) != MACH_PORT_TYPE_NONE);
+               if ((entry->ie_bits & MACH_PORT_TYPE_PORT_RIGHTS) != MACH_PORT_TYPE_NONE &&
+                   entry->ie_request != IE_REQ_NONE) {
+                       __IGNORE_WCASTALIGN(ipc_port_t port = (ipc_port_t) entry->ie_object);
+
+                       assert(IP_VALID(port));
+                       ip_lock(port);
+                       iin->iin_type |= ipc_port_request_type(port, iin->iin_name, entry->ie_request);
+                       ip_unlock(port);
+               }
 
-               iin->iin_name = tentry->ite_name;
-               iin->iin_collision = (bits & IE_BITS_COLLISION) ? TRUE : FALSE;
-               iin->iin_type = IE_BITS_TYPE(bits);
                iin->iin_urefs = IE_BITS_UREFS(bits);
-               iin->iin_object = (vm_offset_t) entry->ie_object;
+               iin->iin_object = (dbg_ok) ? (natural_t)VM_KERNEL_ADDRPERM((uintptr_t)entry->ie_object) : 0;
                iin->iin_next = entry->ie_next;
                iin->iin_hash = entry->ie_index;
-
-               if (tentry->ite_lchild == ITE_NULL)
-                       iitn->iitn_lchild = MACH_PORT_NULL;
-               else
-                       iitn->iitn_lchild = tentry->ite_lchild->ite_name;
-
-               if (tentry->ite_rchild == ITE_NULL)
-                       iitn->iitn_rchild = MACH_PORT_NULL;
-               else
-                       iitn->iitn_rchild = tentry->ite_rchild->ite_name;
-
        }
-       ipc_splay_traverse_finish(&space->is_tree);
-       is_read_unlock(space);
-
-       if (table_info == *tablep) {
-               /* data fit in-line; nothing to deallocate */
-
-               *tableCntp = table_actual;
-       } else if (table_actual == 0) {
-               kmem_free(ipc_kernel_map, table_addr, table_size);
-
-               *tableCntp = 0;
-       } else {
-               vm_size_t size_used, rsize_used;
-               vm_map_copy_t copy;
-
-               /* kmem_alloc doesn't zero memory */
-
-               size_used = table_actual * sizeof *table_info;
-               rsize_used = round_page_32(size_used);
-
-               if (rsize_used != table_size)
-                       kmem_free(ipc_kernel_map,
-                                 table_addr + rsize_used,
-                                 table_size - rsize_used);
 
-               if (size_used != rsize_used)
-                       bzero((char *) (table_addr + size_used),
-                             rsize_used - size_used);
+       is_read_unlock(space);
 
-               kr = vm_map_unwire(ipc_kernel_map, table_addr,
-                                  table_addr + rsize_used, FALSE);
+       /* prepare the table out-of-line data for return */
+       if (table_size > 0) {
+               vm_size_t used_table_size;
+
+               used_table_size = infop->iis_table_size * sizeof(ipc_info_name_t);
+               if (table_size > used_table_size)
+                       bzero((char *)&table_info[infop->iis_table_size],
+                             table_size - used_table_size);
+
+               kr = vm_map_unwire(
+                       ipc_kernel_map,
+                       vm_map_trunc_page(table_addr,
+                                         VM_MAP_PAGE_MASK(ipc_kernel_map)),
+                       vm_map_round_page(table_addr + table_size,
+                                         VM_MAP_PAGE_MASK(ipc_kernel_map)),
+                       FALSE);
                assert(kr == KERN_SUCCESS);
-
-               kr = vm_map_copyin(ipc_kernel_map, table_addr, rsize_used,
-                                  TRUE, &copy);
+               kr = vm_map_copyin(ipc_kernel_map, (vm_map_address_t)table_addr, 
+                                  (vm_map_size_t)used_table_size, TRUE, &copy);
                assert(kr == KERN_SUCCESS);
-
-               *tablep = (ipc_info_name_t *) copy;
-               *tableCntp = table_actual;
-       }
-
-       if (tree_info == *treep) {
-               /* data fit in-line; nothing to deallocate */
-
-               *treeCntp = tree_actual;
-       } else if (tree_actual == 0) {
-               kmem_free(ipc_kernel_map, tree_addr, tree_size);
-
-               *treeCntp = 0;
+               *tablep = (ipc_info_name_t *)copy;
+               *tableCntp = infop->iis_table_size;
        } else {
-               vm_size_t size_used, rsize_used;
-               vm_map_copy_t copy;
+               *tablep = (ipc_info_name_t *)0;
+               *tableCntp = 0;
+       }
 
-               /* kmem_alloc doesn't zero memory */
+       /* splay tree is obsolete, no work to do... */
+       *treep = (ipc_info_tree_name_t *)0;
+       *treeCntp = 0;
+       return KERN_SUCCESS;
+}
+#endif /* MACH_IPC_DEBUG */
 
-               size_used = tree_actual * sizeof *tree_info;
-               rsize_used = round_page_32(size_used);
+/*
+ *     Routine:        mach_port_space_basic_info
+ *     Purpose:
+ *             Returns basic information about an IPC space.
+ *     Conditions:
+ *             Nothing locked.
+ *     Returns:
+ *             KERN_SUCCESS            Returned information.
+ *             KERN_FAILURE            The call is not supported.
+ *             KERN_INVALID_TASK       The space is dead.
+ */
 
-               if (rsize_used != tree_size)
-                       kmem_free(ipc_kernel_map,
-                                 tree_addr + rsize_used,
-                                 tree_size - rsize_used);
+#if !MACH_IPC_DEBUG
+kern_return_t
+mach_port_space_basic_info(
+       __unused ipc_space_t                    space,
+       __unused ipc_info_space_basic_t         *infop)
+{
+        return KERN_FAILURE;
+}
+#else
+kern_return_t
+mach_port_space_basic_info(
+       ipc_space_t                     space,
+       ipc_info_space_basic_t          *infop)
+{
+       if (space == IS_NULL)
+               return KERN_INVALID_TASK;
 
-               if (size_used != rsize_used)
-                       bzero((char *) (tree_addr + size_used),
-                             rsize_used - size_used);
 
-               kr = vm_map_unwire(ipc_kernel_map, tree_addr,
-                                  tree_addr + rsize_used, FALSE);
-               assert(kr == KERN_SUCCESS);
+       is_read_lock(space);
+       if (!is_active(space)) {
+               is_read_unlock(space);
+               return KERN_INVALID_TASK;
+       }
 
-               kr = vm_map_copyin(ipc_kernel_map, tree_addr, rsize_used,
-                                  TRUE, &copy);
-               assert(kr == KERN_SUCCESS);
+       /* get the basic space info */
+       infop->iisb_genno_mask = MACH_PORT_NGEN(MACH_PORT_DEAD);
+       infop->iisb_table_size = space->is_table_size;
+       infop->iisb_table_next = space->is_table_next->its_size;
+       infop->iisb_table_inuse = space->is_table_size - space->is_table_free - 1;
+       infop->iisb_reserved[0] = 0;
+       infop->iisb_reserved[1] = 0;
 
-               *treep = (ipc_info_tree_name_t *) copy;
-               *treeCntp = tree_actual;
-       }
+       is_read_unlock(space);
 
        return KERN_SUCCESS;
-#endif /* MACH_IPC_DEBUG */
 }
+#endif /* MACH_IPC_DEBUG */
 
 /*
  *     Routine:        mach_port_dnrequest_info
@@ -476,16 +366,24 @@ mach_port_space_info(
  *             KERN_INVALID_RIGHT      Name doesn't denote receive rights.
  */
 
+#if !MACH_IPC_DEBUG
 kern_return_t
 mach_port_dnrequest_info(
-       ipc_space_t             space,
-       mach_port_name_t        name,
-       unsigned int            *totalp,
-       unsigned int            *usedp)
+       __unused ipc_space_t            space,
+       __unused mach_port_name_t       name,
+       __unused unsigned int   *totalp,
+       __unused unsigned int   *usedp)
 {
-#if !MACH_IPC_DEBUG
         return KERN_FAILURE;
+}
 #else
+kern_return_t
+mach_port_dnrequest_info(
+       ipc_space_t                     space,
+       mach_port_name_t                name,
+       unsigned int                    *totalp,
+       unsigned int                    *usedp)
+{
        unsigned int total, used;
        ipc_port_t port;
        kern_return_t kr;
@@ -498,18 +396,18 @@ mach_port_dnrequest_info(
                return kr;
        /* port is locked and active */
 
-       if (port->ip_dnrequests == IPR_NULL) {
+       if (port->ip_requests == IPR_NULL) {
                total = 0;
                used = 0;
        } else {
-               ipc_port_request_t dnrequests = port->ip_dnrequests;
+               ipc_port_request_t requests = port->ip_requests;
                ipc_port_request_index_t index;
 
-               total = dnrequests->ipr_size->its_size;
+               total = requests->ipr_size->its_size;
 
                for (index = 1, used = 0;
                     index < total; index++) {
-                       ipc_port_request_t ipr = &dnrequests[index];
+                       ipc_port_request_t ipr = &requests[index];
 
                        if (ipr->ipr_name != MACH_PORT_NULL)
                                used++;
@@ -520,14 +418,17 @@ mach_port_dnrequest_info(
        *totalp = total;
        *usedp = used;
        return KERN_SUCCESS;
-#endif /* MACH_IPC_DEBUG */
 }
+#endif /* MACH_IPC_DEBUG */
 
 /*
- *     Routine:        mach_port_kernel_object [kernel call]
+ *     Routine:        mach_port_kobject [kernel call]
  *     Purpose:
  *             Retrieve the type and address of the kernel object
- *             represented by a send or receive right.
+ *             represented by a send or receive right. Returns
+ *             the kernel address in a mach_vm_address_t to
+ *             mask potential differences in kernel address space
+ *             size.
  *     Conditions:
  *             Nothing locked.
  *     Returns:
@@ -539,19 +440,31 @@ mach_port_dnrequest_info(
  *                                     send or receive rights.
  */
 
+#if !MACH_IPC_DEBUG
 kern_return_t
-mach_port_kernel_object(
-       ipc_space_t             space,
-       mach_port_name_t        name,
-       unsigned int            *typep,
-       vm_offset_t             *addrp)
+mach_port_kobject(
+       __unused ipc_space_t            space,
+       __unused mach_port_name_t       name,
+       __unused natural_t              *typep,
+       __unused mach_vm_address_t      *addrp)
 {
-#if !MACH_IPC_DEBUG
         return KERN_FAILURE;
+}
 #else
+kern_return_t
+mach_port_kobject(
+       ipc_space_t                     space,
+       mach_port_name_t                name,
+       natural_t                       *typep,
+       mach_vm_address_t               *addrp)
+{
        ipc_entry_t entry;
        ipc_port_t port;
        kern_return_t kr;
+       mach_vm_address_t kaddr;
+
+       if (space == IS_NULL)
+               return KERN_INVALID_TASK;
 
        kr = ipc_right_lookup_read(space, name, &entry);
        if (kr != KERN_SUCCESS)
@@ -563,7 +476,7 @@ mach_port_kernel_object(
                return KERN_INVALID_RIGHT;
        }
 
-       port = (ipc_port_t) entry->ie_object;
+       __IGNORE_WCASTALIGN(port = (ipc_port_t) entry->ie_object);
        assert(port != IP_NULL);
 
        ip_lock(port);
@@ -575,9 +488,60 @@ mach_port_kernel_object(
        }
 
        *typep = (unsigned int) ip_kotype(port);
-       *addrp = (vm_offset_t) port->ip_kobject;
+       kaddr = (mach_vm_address_t)port->ip_kobject;
        ip_unlock(port);
-       return KERN_SUCCESS;
 
+#if (DEVELOPMENT || DEBUG)
+       if (0 != kaddr && is_ipc_kobject(*typep))
+               *addrp = VM_KERNEL_UNSLIDE_OR_PERM(kaddr);
+       else
+#endif
+               *addrp = 0;
+
+       return KERN_SUCCESS;
+}
 #endif /* MACH_IPC_DEBUG */
+/*
+ *     Routine:        mach_port_kernel_object [Legacy kernel call]
+ *     Purpose:
+ *             Retrieve the type and address of the kernel object
+ *             represented by a send or receive right. Hard-coded
+ *             to return only the low-order 32-bits of the kernel
+ *             object.
+ *     Conditions:
+ *             Nothing locked.
+ *     Returns:
+ *             KERN_SUCCESS            Retrieved kernel object info.
+ *             KERN_INVALID_TASK       The space is null.
+ *             KERN_INVALID_TASK       The space is dead.
+ *             KERN_INVALID_NAME       The name doesn't denote a right.
+ *             KERN_INVALID_RIGHT      Name doesn't denote
+ *                                     send or receive rights.
+ */
+
+#if !MACH_IPC_DEBUG
+kern_return_t
+mach_port_kernel_object(
+       __unused ipc_space_t            space,
+       __unused mach_port_name_t       name,
+       __unused unsigned int           *typep,
+       __unused unsigned int           *addrp)
+{
+        return KERN_FAILURE;
+}
+#else
+kern_return_t
+mach_port_kernel_object(
+       ipc_space_t                     space,
+       mach_port_name_t                name,
+       unsigned int                    *typep,
+       unsigned int                    *addrp)
+{
+       mach_vm_address_t addr = 0;
+       kern_return_t kr;
+
+       kr = mach_port_kobject(space, name, typep, &addr);
+       *addrp = (unsigned int) addr;
+       return kr;
 }
+#endif /* MACH_IPC_DEBUG */