dyld3/MachOAppCache.cpp

   1 /*
   2 * Copyright (c) 2017 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
  24 #include "MachOAppCache.h"
  25
  26 #include <list>
  27
  28 #include <CoreFoundation/CFArray.h>
  29 #include <CoreFoundation/CFPropertyList.h>
  30 #include <CoreFoundation/CFString.h>
  31
  32 #ifndef LC_FILESET_ENTRY
  33 #define LC_FILESET_ENTRY      (0x35 | LC_REQ_DYLD) /* used with fileset_entry_command */
  34 struct fileset_entry_command {
  35     uint32_t        cmd;        /* LC_FILESET_ENTRY */
  36     uint32_t        cmdsize;    /* includes id string */
  37     uint64_t        vmaddr;     /* memory address of the dylib */
  38     uint64_t        fileoff;    /* file offset of the dylib */
  39     union lc_str    entry_id;   /* contained entry id */
  40     uint32_t        reserved;   /* entry_id is 32-bits long, so this is the reserved padding */
  41 };
  42 #endif
  43
  44 namespace dyld3 {
  45
  46 void MachOAppCache::forEachDylib(Diagnostics& diag, void (^callback)(const MachOAnalyzer* ma, const char* name, bool& stop)) const {
  47     const intptr_t slide = getSlide();
  48     forEachLoadCommand(diag, ^(const load_command *cmd, bool &stop) {
  49         if (cmd->cmd == LC_FILESET_ENTRY) {
  50             const fileset_entry_command* app_cache_cmd = (const fileset_entry_command*)cmd;
  51             const char* name = (char*)app_cache_cmd + app_cache_cmd->entry_id.offset;
  52             callback((const MachOAnalyzer*)(app_cache_cmd->vmaddr + slide), name, stop);
  53             return;
  54         }
  55     });
  56 }
  57
  58 void MachOAppCache::forEachPrelinkInfoLibrary(Diagnostics& diags,
  59                                               void (^callback)(const char* bundleName, const char* relativePath,
  60                                                                const std::vector<const char*>& deps)) const  {
  61
  62      __block std::list<std::string> nonASCIIStrings;
  63      auto getString = ^(Diagnostics& diags, CFStringRef symbolNameRef) {
  64          const char* symbolName = CFStringGetCStringPtr(symbolNameRef, kCFStringEncodingUTF8);
  65          if ( symbolName != nullptr )
  66              return symbolName;
  67
  68          CFIndex len = CFStringGetMaximumSizeForEncoding(CFStringGetLength(symbolNameRef), kCFStringEncodingUTF8);
  69          char buffer[len + 1];
  70          if ( !CFStringGetCString(symbolNameRef, buffer, len, kCFStringEncodingUTF8) ) {
  71              diags.error("Could not convert string to ASCII");
  72              return (const char*)nullptr;
  73          }
  74          buffer[len] = '\0';
  75          nonASCIIStrings.push_back(buffer);
  76          return nonASCIIStrings.back().c_str();
  77      };
  78
  79     const uint8_t* prelinkInfoBuffer = nullptr;
  80     uint64_t prelinkInfoBufferSize = 0;
  81     prelinkInfoBuffer = (const uint8_t*)findSectionContent("__PRELINK_INFO", "__info", prelinkInfoBufferSize);
  82     if ( prelinkInfoBuffer == nullptr )
  83         return;
  84
  85     CFReadStreamRef readStreamRef = CFReadStreamCreateWithBytesNoCopy(kCFAllocatorDefault, prelinkInfoBuffer, prelinkInfoBufferSize, kCFAllocatorNull);
  86     if ( !CFReadStreamOpen(readStreamRef) ) {
  87         fprintf(stderr, "Could not open plist stream\n");
  88         exit(1);
  89     }
  90     CFErrorRef errorRef = nullptr;
  91     CFPropertyListRef plistRef = CFPropertyListCreateWithStream(kCFAllocatorDefault, readStreamRef, prelinkInfoBufferSize, kCFPropertyListImmutable, nullptr, &errorRef);
  92     if ( errorRef != nullptr ) {
  93         CFStringRef stringRef = CFErrorCopyFailureReason(errorRef);
  94         fprintf(stderr, "Could not read plist because: %s\n", CFStringGetCStringPtr(stringRef, kCFStringEncodingASCII));
  95         CFRelease(stringRef);
  96         exit(1);
  97     }
  98     assert(CFGetTypeID(plistRef) == CFDictionaryGetTypeID());
  99
 100     // Get the "_PrelinkInfoDictionary" array
 101     CFArrayRef prelinkInfoDictionaryArrayRef = (CFArrayRef)CFDictionaryGetValue((CFDictionaryRef)plistRef, CFSTR("_PrelinkInfoDictionary"));
 102     assert(CFGetTypeID(prelinkInfoDictionaryArrayRef) == CFArrayGetTypeID());
 103
 104     for (CFIndex i = 0; i != CFArrayGetCount(prelinkInfoDictionaryArrayRef); ++i) {
 105         CFDictionaryRef kextInfoDictionary = (CFDictionaryRef)CFArrayGetValueAtIndex(prelinkInfoDictionaryArrayRef, i);
 106         assert(CFGetTypeID(kextInfoDictionary) == CFDictionaryGetTypeID());
 107
 108         CFStringRef bundleIdentifierStringRef = (CFStringRef)CFDictionaryGetValue((CFDictionaryRef)kextInfoDictionary, CFSTR("CFBundleIdentifier"));
 109         assert(CFGetTypeID(bundleIdentifierStringRef) == CFStringGetTypeID());
 110
 111         const char* bundleID = getString(diags, bundleIdentifierStringRef);
 112         if ( bundleID == nullptr )
 113             return;
 114
 115         const char* relativePath = nullptr;
 116         CFStringRef relativePathStringRef = (CFStringRef)CFDictionaryGetValue((CFDictionaryRef)kextInfoDictionary, CFSTR("_PrelinkExecutableRelativePath"));
 117         if ( relativePathStringRef != nullptr ) {
 118             assert(CFGetTypeID(relativePathStringRef) == CFStringGetTypeID());
 119             relativePath = getString(diags, relativePathStringRef);
 120             if ( relativePath == nullptr )
 121                 return;
 122         }
 123
 124         std::vector<const char*> dependencies;
 125
 126         CFDictionaryRef bundleLibrariesDictionaryRef = (CFDictionaryRef)CFDictionaryGetValue((CFDictionaryRef)kextInfoDictionary, CFSTR("OSBundleLibraries"));
 127         if (bundleLibrariesDictionaryRef != nullptr) {
 128             // Add the libraries to the dependencies
 129             // If we didn't have bundle libraries then a placeholder was added
 130             assert(CFGetTypeID(bundleLibrariesDictionaryRef) == CFDictionaryGetTypeID());
 131
 132             struct ApplyContext {
 133                 Diagnostics*                diagnostics;
 134                 std::vector<const char*>*   dependencies                                    = nullptr;
 135                 const char* (^getString)(Diagnostics& diags, CFStringRef symbolNameRef)     = nullptr;
 136             };
 137
 138             CFDictionaryApplierFunction callback = [](const void *key, const void *value, void *context) {
 139                 CFStringRef keyStringRef = (CFStringRef)key;
 140                 assert(CFGetTypeID(keyStringRef) == CFStringGetTypeID());
 141
 142                 ApplyContext* applyContext = (ApplyContext*)context;
 143                 const char* depString = applyContext->getString(*applyContext->diagnostics, keyStringRef);
 144                 if ( !depString )
 145                     return;
 146
 147                 applyContext->dependencies->push_back(depString);
 148             };
 149
 150             ApplyContext applyContext = { &diags, &dependencies, getString };
 151             CFDictionaryApplyFunction(bundleLibrariesDictionaryRef, callback, &applyContext);
 152
 153             if ( diags.hasError() )
 154                 return;
 155         }
 156         callback(bundleID, relativePath, dependencies);
 157     }
 158
 159     CFRelease(plistRef);
 160     CFRelease(readStreamRef);
 161 }
 162
 163 } // namespace dyld3