xnu-792.24.17.tar.gz

[apple/xnu.git] / osfmk / kern / ipc_tt.c

diff --git a/osfmk/kern/ipc_tt.c b/osfmk/kern/ipc_tt.c
index 2f6a9521f8366142ab1aa8ab48b5a89ef1e602a3..24f41f7545d84cb8b1ac1bb1b692a20f37a4d40d 100644 (file)
--- a/osfmk/kern/ipc_tt.c
+++ b/osfmk/kern/ipc_tt.c
@@ -1,29 +1,23 @@
 /*
  * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
  *
- * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ * @APPLE_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. 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.
+ * The contents of this file constitute Original Code as defined in and
+ * are subject to the Apple Public Source License Version 1.1 (the
+ * "License").  You may not use this file except in compliance with the
+ * License.  Please obtain a copy of the License at
+ * http://www.apple.com/publicsource and read it before using this file.
  * 
- * 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
+ * This 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,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * 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.
+ * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
+ * License for the specific language governing rights and limitations
+ * under the License.
  * 
- * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
+ * @APPLE_LICENSE_HEADER_END@
  */
 /*
  * @OSF_COPYRIGHT@
@@ -423,6 +417,74 @@ ipc_thread_terminate(
        thread->ith_rpc_reply = IP_NULL;
 }
 
+/*
+ *     Routine:        ipc_thread_reset
+ *     Purpose:
+ *             Reset the IPC state for a given Mach thread when
+ *             its task enters an elevated security context.
+ *             Both the thread port and its exception ports have
+ *             to be reset.  Its RPC reply port cannot have any
+ *             rights outstanding, so it should be fine.
+ *     Conditions:
+ *             Nothing locked.
+ */
+
+void
+ipc_thread_reset(
+       thread_t        thread)
+{
+       ipc_port_t old_kport, new_kport;
+       ipc_port_t old_sself;
+       ipc_port_t old_exc_actions[EXC_TYPES_COUNT];
+       int i;
+
+       new_kport = ipc_port_alloc_kernel();
+       if (new_kport == IP_NULL)
+               panic("ipc_task_reset");
+
+       thread_mtx_lock(thread);
+
+       old_kport = thread->ith_self;
+
+       if (old_kport == IP_NULL) {
+               /* the  is already terminated (can this happen?) */
+               thread_mtx_unlock(thread);
+               ipc_port_dealloc_kernel(new_kport);
+               return;
+       }
+
+       thread->ith_self = new_kport;
+       old_sself = thread->ith_sself;
+       thread->ith_sself = ipc_port_make_send(new_kport);
+       ipc_kobject_set(old_kport, IKO_NULL, IKOT_NONE);
+       ipc_kobject_set(new_kport, (ipc_kobject_t) thread, IKOT_THREAD);
+
+       for (i = FIRST_EXCEPTION; i < EXC_TYPES_COUNT; i++) {
+               if (!thread->exc_actions[i].privileged) {
+                       old_exc_actions[i] = thread->exc_actions[i].port;
+                       thread->exc_actions[i].port = IP_NULL;
+               } else {
+                       old_exc_actions[i] = IP_NULL;
+               }
+       }/* for */
+
+       thread_mtx_unlock(thread);
+
+       /* release the naked send rights */
+
+       if (IP_VALID(old_sself))
+               ipc_port_release_send(old_sself);
+
+       for (i = FIRST_EXCEPTION; i < EXC_TYPES_COUNT; i++) {
+               if (IP_VALID(old_exc_actions[i])) {
+                       ipc_port_release_send(old_exc_actions[i]);
+               }
+       }/* for */
+
+       /* destroy the kernel port */
+       ipc_port_dealloc_kernel(old_kport);
+}
+
 /*
  *     Routine:        retrieve_task_self_fast
  *     Purpose:
@@ -1272,6 +1334,7 @@ thread_set_exception_ports(
        thread_state_flavor_t   new_flavor)
 {
        ipc_port_t              old_port[EXC_TYPES_COUNT];
+       boolean_t privileged = current_task()->sec_token.val[0] == 0;
        register int    i;
 
        if (thread == THREAD_NULL)
@@ -1315,6 +1378,7 @@ thread_set_exception_ports(
                        thread->exc_actions[i].port = ipc_port_copy_send(new_port);
                        thread->exc_actions[i].behavior = new_behavior;
                        thread->exc_actions[i].flavor = new_flavor;
+                       thread->exc_actions[i].privileged = privileged;
                }
                else
                        old_port[i] = IP_NULL;
@@ -1437,6 +1501,7 @@ thread_swap_exception_ports(
        thread_state_flavor_array_t     flavors)
 {
        ipc_port_t              old_port[EXC_TYPES_COUNT];
+       boolean_t privileged = current_task()->sec_token.val[0] == 0;
        unsigned int    i, j, count;
 
        if (thread == THREAD_NULL)
@@ -1496,6 +1561,7 @@ thread_swap_exception_ports(
                        thread->exc_actions[i].port = ipc_port_copy_send(new_port);
                        thread->exc_actions[i].behavior = new_behavior;
                        thread->exc_actions[i].flavor = new_flavor;
+                       thread->exc_actions[i].privileged = privileged;
                        if (count > *CountCnt)
                                break;
                }