unit-tests/test-cases/read-only-stubs/foo.c

   1 /*
   2  * Copyright (c) 2007 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23 #include <stdio.h>  // fprintf(), NULL
  24 #include <stdlib.h> // exit(), EXIT_SUCCESS
  25 #include <unistd.h>
  26 #include <mach-o/getsect.h>
  27 #include <mach-o/ldsyms.h>
  28 #include <mach/mach.h>
  29 #include <mach/mach_vm.h>
  30
  31 #include "test.h" // PASS(), FAIL(), XPASS(), XFAIL()
  32
  33 extern void bar();
  34 extern int barData;
  35
  36
  37 static vm_prot_t getPermission(void* addr)
  38 {
  39     mach_vm_address_t                           address = (mach_vm_address_t)(uintptr_t)addr;
  40     kern_return_t                                       result;
  41     mach_port_t                                         object_name;
  42     vm_region_basic_info_data_64_t      info;
  43     mach_msg_type_number_t                      count;
  44     mach_vm_size_t                                      size = 4096;
  45
  46         count = VM_REGION_BASIC_INFO_COUNT_64;
  47         result = mach_vm_region(mach_task_self(),
  48                                         &address,
  49                                         &size,
  50                                         VM_REGION_BASIC_INFO_64,
  51                                         (vm_region_info_t)&info,
  52                                         &count,
  53                                         &object_name);
  54         if ( result == KERN_SUCCESS )
  55                 return info.protection;
  56         return 0;
  57 }
  58
  59
  60 static void* getStubAddr()
  61 {
  62 #if __LP64__
  63         uint64_t size;
  64 #else
  65         uint32_t size;
  66 #endif
  67         uintptr_t slide = (uintptr_t)&_mh_dylib_header; // assume dylib is zero-base so slide == load address
  68 #if __i386__
  69         return getsectdatafromheader(&_mh_dylib_header, "__IMPORT", "__jump_table", &size) + slide;
  70 #elif __ppc__
  71         return getsectdatafromheader(&_mh_dylib_header, "TEXT", "__picsymbolstub1", &size) + slide;
  72 #elif __ppc64__
  73         return getsectdatafromheader_64(&_mh_dylib_header, "__TEXT", "__picsymbolstub1", &size) + slide;
  74 #elif __x86_64__
  75         return getsectdatafromheader_64(&_mh_dylib_header, "__TEXT", "__symbol_stub1", &size) + slide;
  76 #elif __arm__
  77         void* p = getsectdata("__TEXT", "__picsymbolstub4", (unsigned long*)&size);
  78         if ( p != NULL )
  79                 return getsectdatafromheader(&_mh_dylib_header, "__TEXT", "__picsymbolstub4", &size) + slide;
  80         return getsectdatafromheader(&_mh_dylib_header, "__TEXT", "__symbolstub1", &size) + slide;
  81 #else
  82         #error unknown arch
  83 #endif
  84 }
  85
  86
  87 static void checkStubs(void* addr)
  88 {
  89         vm_prot_t perm = getPermission(addr);
  90         if ( (perm == 0) || ((perm & VM_PROT_WRITE) != 0) ) {
  91                 FAIL("read-only-stubs: bad permissions %d at address %p", perm, addr);
  92                 exit(0);
  93         }
  94 }
  95
  96 int fooData = 1;
  97
  98 void foo()
  99 {
 100         void* stubAddr = getStubAddr();
 101         checkStubs(stubAddr);
 102         barData = 0;
 103         bar();
 104         checkStubs(stubAddr);
 105 }
 106
 107