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--- dyld/dyld-625.13/dyld3/SharedCacheRuntime.cpp
+++ /dev/null
@@ -1,782 +0,0 @@
-/*
- * Copyright (c) 2017 Apple Inc. All rights reserved.
- *
- * @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. 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,
- * 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.
- *
- * @APPLE_LICENSE_HEADER_END@
- */
-
-
-
-#include <stdint.h>
-#include <string.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include <sys/param.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/syscall.h>
-#include <sys/syslog.h>
-#include <sys/sysctl.h>
-#include <sys/mman.h>
-#include <mach/mach.h>
-#include <mach-o/fat.h>
-#include <mach-o/loader.h>
-#include <mach-o/ldsyms.h>
-#include <mach/shared_region.h>
-#include <mach/mach.h>
-#include <Availability.h>
-#include <TargetConditionals.h>
-
-#include "dyld_cache_format.h"
-#include "SharedCacheRuntime.h"
-#include "Loading.h"
-
-#define ENABLE_DYLIBS_TO_OVERRIDE_CACHE_SIZE 1024
-
-// should be in mach/shared_region.h
-extern "C" int __shared_region_check_np(uint64_t* startaddress);
-extern "C" int __shared_region_map_and_slide_np(int fd, uint32_t count, const shared_file_mapping_np mappings[], long slide, const dyld_cache_slide_info2* slideInfo, size_t slideInfoSize);
-
-
-namespace dyld {
- extern int my_stat(const char* path, struct stat* buf);
- extern int my_open(const char* path, int flag, int other);
- extern void log(const char*, ...);
-}
-
-
-namespace dyld3 {
-
-
-struct CacheInfo
-{
- int fd;
- shared_file_mapping_np mappings[3];
- uint64_t slideInfoAddressUnslid;
- size_t slideInfoSize;
- uint64_t cachedDylibsGroupUnslid;
- uint64_t sharedRegionStart;
- uint64_t sharedRegionSize;
- uint64_t maxSlide;
-};
-
-
-
-
-#if __i386__
- #define ARCH_NAME "i386"
- #define ARCH_CACHE_MAGIC "dyld_v1 i386"
-#elif __x86_64__
- #define ARCH_NAME "x86_64"
- #define ARCH_CACHE_MAGIC "dyld_v1 x86_64"
- #define ARCH_NAME_H "x86_64h"
- #define ARCH_CACHE_MAGIC_H "dyld_v1 x86_64h"
-#elif __ARM_ARCH_7K__
- #define ARCH_NAME "armv7k"
- #define ARCH_CACHE_MAGIC "dyld_v1 armv7k"
-#elif __ARM_ARCH_7A__
- #define ARCH_NAME "armv7"
- #define ARCH_CACHE_MAGIC "dyld_v1 armv7"
-#elif __ARM_ARCH_7S__
- #define ARCH_NAME "armv7s"
- #define ARCH_CACHE_MAGIC "dyld_v1 armv7s"
-#elif __arm64e__
- #define ARCH_NAME "arm64e"
- #define ARCH_CACHE_MAGIC "dyld_v1 arm64e"
-#elif __arm64__
- #if __LP64__
- #define ARCH_NAME "arm64"
- #define ARCH_CACHE_MAGIC "dyld_v1 arm64"
- #else
- #define ARCH_NAME "arm64_32"
- #define ARCH_CACHE_MAGIC "dyld_v1arm64_32"
- #endif
-#endif
-
-
-
-static void rebaseChainV2(uint8_t* pageContent, uint16_t startOffset, uintptr_t slideAmount, const dyld_cache_slide_info2* slideInfo)
-{
- const uintptr_t deltaMask = (uintptr_t)(slideInfo->delta_mask);
- const uintptr_t valueMask = ~deltaMask;
- const uintptr_t valueAdd = (uintptr_t)(slideInfo->value_add);
- const unsigned deltaShift = __builtin_ctzll(deltaMask) - 2;
-
- uint32_t pageOffset = startOffset;
- uint32_t delta = 1;
- while ( delta != 0 ) {
- uint8_t* loc = pageContent + pageOffset;
- uintptr_t rawValue = *((uintptr_t*)loc);
- delta = (uint32_t)((rawValue & deltaMask) >> deltaShift);
- uintptr_t value = (rawValue & valueMask);
- if ( value != 0 ) {
- value += valueAdd;
- value += slideAmount;
- }
- *((uintptr_t*)loc) = value;
- //dyld::log(" pageOffset=0x%03X, loc=%p, org value=0x%08llX, new value=0x%08llX, delta=0x%X\n", pageOffset, loc, (uint64_t)rawValue, (uint64_t)value, delta);
- pageOffset += delta;
- }
-}
-
-#if !__LP64__
-static void rebaseChainV4(uint8_t* pageContent, uint16_t startOffset, uintptr_t slideAmount, const dyld_cache_slide_info4* slideInfo)
-{
- const uintptr_t deltaMask = (uintptr_t)(slideInfo->delta_mask);
- const uintptr_t valueMask = ~deltaMask;
- const uintptr_t valueAdd = (uintptr_t)(slideInfo->value_add);
- const unsigned deltaShift = __builtin_ctzll(deltaMask) - 2;
-
- uint32_t pageOffset = startOffset;
- uint32_t delta = 1;
- while ( delta != 0 ) {
- uint8_t* loc = pageContent + pageOffset;
- uintptr_t rawValue = *((uintptr_t*)loc);
- delta = (uint32_t)((rawValue & deltaMask) >> deltaShift);
- uintptr_t value = (rawValue & valueMask);
- if ( (value & 0xFFFF8000) == 0 ) {
- // small positive non-pointer, use as-is
- }
- else if ( (value & 0x3FFF8000) == 0x3FFF8000 ) {
- // small negative non-pointer
- value |= 0xC0000000;
- }
- else {
- value += valueAdd;
- value += slideAmount;
- }
- *((uintptr_t*)loc) = value;
- //dyld::log(" pageOffset=0x%03X, loc=%p, org value=0x%08llX, new value=0x%08llX, delta=0x%X\n", pageOffset, loc, (uint64_t)rawValue, (uint64_t)value, delta);
- pageOffset += delta;
- }
-}
-#endif
-
-static void getCachePath(const SharedCacheOptions& options, size_t pathBufferSize, char pathBuffer[])
-{
- // set cache dir
- if ( options.cacheDirOverride != nullptr ) {
- strlcpy(pathBuffer, options.cacheDirOverride, pathBufferSize);
- }
- else {
-#if __IPHONE_OS_VERSION_MIN_REQUIRED
- strlcpy(pathBuffer, IPHONE_DYLD_SHARED_CACHE_DIR, sizeof(IPHONE_DYLD_SHARED_CACHE_DIR));
-#else
- strlcpy(pathBuffer, MACOSX_DYLD_SHARED_CACHE_DIR, sizeof(MACOSX_DYLD_SHARED_CACHE_DIR));
-#endif
- }
-
- // append file component of cache file
- if ( pathBuffer[strlen(pathBuffer)-1] != '/' )
- strlcat(pathBuffer, "/", pathBufferSize);
-#if __x86_64__ && !__IPHONE_OS_VERSION_MIN_REQUIRED
- if ( options.useHaswell ) {
- size_t len = strlen(pathBuffer);
- struct stat haswellStatBuf;
- strlcat(pathBuffer, DYLD_SHARED_CACHE_BASE_NAME ARCH_NAME_H, pathBufferSize);
- if ( dyld::my_stat(pathBuffer, &haswellStatBuf) == 0 )
- return;
- // no haswell cache file, use regular x86_64 cache
- pathBuffer[len] = '\0';
- }
-#endif
- strlcat(pathBuffer, DYLD_SHARED_CACHE_BASE_NAME ARCH_NAME, pathBufferSize);
-
-#if __IPHONE_OS_VERSION_MIN_REQUIRED && !TARGET_IPHONE_SIMULATOR
- // use .development cache if it exists
- struct stat enableStatBuf;
- struct stat devCacheStatBuf;
- struct stat optCacheStatBuf;
- bool developmentDevice = dyld3::internalInstall();
- bool enableFileExists = (dyld::my_stat(IPHONE_DYLD_SHARED_CACHE_DIR "enable-dylibs-to-override-cache", &enableStatBuf) == 0);
- bool devCacheExists = (dyld::my_stat(IPHONE_DYLD_SHARED_CACHE_DIR DYLD_SHARED_CACHE_BASE_NAME ARCH_NAME DYLD_SHARED_CACHE_DEVELOPMENT_EXT, &devCacheStatBuf) == 0);
- bool optCacheExists = (dyld::my_stat(IPHONE_DYLD_SHARED_CACHE_DIR DYLD_SHARED_CACHE_BASE_NAME ARCH_NAME, &optCacheStatBuf) == 0);
- if ( developmentDevice && ((enableFileExists && (enableStatBuf.st_size < ENABLE_DYLIBS_TO_OVERRIDE_CACHE_SIZE) && devCacheExists) || !optCacheExists) )
- strlcat(pathBuffer, DYLD_SHARED_CACHE_DEVELOPMENT_EXT, pathBufferSize);
-#endif
-
-}
-
-
-int openSharedCacheFile(const SharedCacheOptions& options, SharedCacheLoadInfo* results)
-{
- getCachePath(options, sizeof(results->path), results->path);
- return dyld::my_open(results->path, O_RDONLY, 0);
-}
-
-static bool validMagic(const SharedCacheOptions& options, const DyldSharedCache* cache)
-{
- if ( strcmp(cache->header.magic, ARCH_CACHE_MAGIC) == 0 )
- return true;
-
-#if __x86_64__
- if ( options.useHaswell ) {
- if ( strcmp(cache->header.magic, ARCH_CACHE_MAGIC_H) == 0 )
- return true;
- }
-#endif
- return false;
-}
-
-
-static bool validPlatform(const SharedCacheOptions& options, const DyldSharedCache* cache)
-{
- // grandfather in old cache that does not have platform in header
- if ( cache->header.mappingOffset < 0xE0 )
- return true;
-
- if ( cache->header.platform != (uint32_t)MachOFile::currentPlatform() )
- return false;
-
-#if TARGET_IPHONE_SIMULATOR
- if ( cache->header.simulator == 0 )
- return false;
-#else
- if ( cache->header.simulator != 0 )
- return false;
-#endif
-
- return true;
-}
-
-
-static void verboseSharedCacheMappings(const shared_file_mapping_np mappings[3])
-{
- for (int i=0; i < 3; ++i) {
- dyld::log(" 0x%08llX->0x%08llX init=%x, max=%x %s%s%s\n",
- mappings[i].sfm_address, mappings[i].sfm_address+mappings[i].sfm_size-1,
- mappings[i].sfm_init_prot, mappings[i].sfm_init_prot,
- ((mappings[i].sfm_init_prot & VM_PROT_READ) ? "read " : ""),
- ((mappings[i].sfm_init_prot & VM_PROT_WRITE) ? "write " : ""),
- ((mappings[i].sfm_init_prot & VM_PROT_EXECUTE) ? "execute " : ""));
- }
-}
-
-static bool preflightCacheFile(const SharedCacheOptions& options, SharedCacheLoadInfo* results, CacheInfo* info)
-{
- // find and open shared cache file
- int fd = openSharedCacheFile(options, results);
- if ( fd == -1 ) {
- results->errorMessage = "shared cache file cannot be opened";
- return false;
- }
-
- struct stat cacheStatBuf;
- if ( dyld::my_stat(results->path, &cacheStatBuf) != 0 ) {
- results->errorMessage = "shared cache file cannot be stat()ed";
- ::close(fd);
- return false;
- }
- size_t cacheFileLength = (size_t)(cacheStatBuf.st_size);
-
- // sanity check header and mappings
- uint8_t firstPage[0x4000];
- if ( ::pread(fd, firstPage, sizeof(firstPage), 0) != sizeof(firstPage) ) {
- results->errorMessage = "shared cache header could not be read";
- ::close(fd);
- return false;
- }
- const DyldSharedCache* cache = (DyldSharedCache*)firstPage;
- if ( !validMagic(options, cache) ) {
- results->errorMessage = "shared cache file has wrong magic";
- ::close(fd);
- return false;
- }
- if ( !validPlatform(options, cache) ) {
- results->errorMessage = "shared cache file is for a different platform";
- ::close(fd);
- return false;
- }
- if ( (cache->header.mappingCount != 3) || (cache->header.mappingOffset > 0x138) ) {
- results->errorMessage = "shared cache file mappings are invalid";
- ::close(fd);
- return false;
- }
- const dyld_cache_mapping_info* const fileMappings = (dyld_cache_mapping_info*)&firstPage[cache->header.mappingOffset];
- if ( (fileMappings[0].fileOffset != 0)
- || ((fileMappings[0].address + fileMappings[0].size) > fileMappings[1].address)
- || ((fileMappings[1].address + fileMappings[1].size) > fileMappings[2].address)
- || ((fileMappings[0].fileOffset + fileMappings[0].size) != fileMappings[1].fileOffset)
- || ((fileMappings[1].fileOffset + fileMappings[1].size) != fileMappings[2].fileOffset)
- || ((cache->header.codeSignatureOffset + cache->header.codeSignatureSize) != cacheFileLength)
- || (fileMappings[0].maxProt != (VM_PROT_READ|VM_PROT_EXECUTE))
- || (fileMappings[1].maxProt != (VM_PROT_READ|VM_PROT_WRITE))
- || (fileMappings[2].maxProt != VM_PROT_READ) ) {
- results->errorMessage = "shared cache file mappings are invalid";
- ::close(fd);
- return false;
- }
-
- if ( cache->header.mappingOffset >= 0xF8 ) {
- if ( (fileMappings[0].address != cache->header.sharedRegionStart) || ((fileMappings[2].address + fileMappings[2].size) > (cache->header.sharedRegionStart+cache->header.sharedRegionSize)) ) {
- results->errorMessage = "shared cache file mapping addressses invalid";
- ::close(fd);
- return false;
- }
- }
- else {
- if ( (fileMappings[0].address != SHARED_REGION_BASE) || ((fileMappings[2].address + fileMappings[2].size) > (SHARED_REGION_BASE+SHARED_REGION_SIZE)) ) {
- results->errorMessage = "shared cache file mapping addressses invalid";
- ::close(fd);
- return false;
- }
- }
-
- // register code signature of cache file
- fsignatures_t siginfo;
- siginfo.fs_file_start = 0; // cache always starts at beginning of file
- siginfo.fs_blob_start = (void*)cache->header.codeSignatureOffset;
- siginfo.fs_blob_size = (size_t)(cache->header.codeSignatureSize);
- int result = fcntl(fd, F_ADDFILESIGS_RETURN, &siginfo);
- if ( result == -1 ) {
- results->errorMessage = "code signature registration for shared cache failed";
- ::close(fd);
- return false;
- }
-
- // <rdar://problem/23188073> validate code signature covers entire shared cache
- uint64_t codeSignedLength = siginfo.fs_file_start;
- if ( codeSignedLength < cache->header.codeSignatureOffset ) {
- results->errorMessage = "code signature does not cover entire shared cache file";
- ::close(fd);
- return false;
- }
- void* mappedData = ::mmap(NULL, sizeof(firstPage), PROT_READ|PROT_EXEC, MAP_PRIVATE, fd, 0);
- if ( mappedData == MAP_FAILED ) {
- results->errorMessage = "first page of shared cache not mmap()able";
- ::close(fd);
- return false;
- }
- if ( memcmp(mappedData, firstPage, sizeof(firstPage)) != 0 ) {
- results->errorMessage = "first page of mmap()ed shared cache not valid";
- ::close(fd);
- return false;
- }
- ::munmap(mappedData, sizeof(firstPage));
-
- // fill out results
- info->fd = fd;
- for (int i=0; i < 3; ++i) {
- info->mappings[i].sfm_address = fileMappings[i].address;
- info->mappings[i].sfm_size = fileMappings[i].size;
- info->mappings[i].sfm_file_offset = fileMappings[i].fileOffset;
- info->mappings[i].sfm_max_prot = fileMappings[i].maxProt;
- info->mappings[i].sfm_init_prot = fileMappings[i].initProt;
- }
- info->mappings[1].sfm_max_prot |= VM_PROT_SLIDE;
- info->mappings[1].sfm_init_prot |= VM_PROT_SLIDE;
- info->slideInfoAddressUnslid = fileMappings[2].address + cache->header.slideInfoOffset - fileMappings[2].fileOffset;
- info->slideInfoSize = (long)cache->header.slideInfoSize;
- if ( cache->header.mappingOffset > 0xD0 )
- info->cachedDylibsGroupUnslid = cache->header.dylibsImageGroupAddr;
- else
- info->cachedDylibsGroupUnslid = 0;
- if ( cache->header.mappingOffset >= 0xf8 ) {
- info->sharedRegionStart = cache->header.sharedRegionStart;
- info->sharedRegionSize = cache->header.sharedRegionSize;
- info->maxSlide = cache->header.maxSlide;
- }
- else {
- info->sharedRegionStart = SHARED_REGION_BASE;
- info->sharedRegionSize = SHARED_REGION_SIZE;
- info->maxSlide = SHARED_REGION_SIZE - (fileMappings[2].address + fileMappings[2].size - fileMappings[0].address);
- }
- return true;
-}
-
-
-#if !TARGET_IPHONE_SIMULATOR
-
-// update all __DATA pages with slide info
-static bool rebaseDataPages(bool isVerbose, CacheInfo& info, SharedCacheLoadInfo* results)
-{
- uint64_t dataPagesStart = info.mappings[1].sfm_address;
- const dyld_cache_slide_info* slideInfo = nullptr;
- if ( info.slideInfoSize != 0 ) {
- slideInfo = (dyld_cache_slide_info*)(info.slideInfoAddressUnslid + results->slide);
- }
- const dyld_cache_slide_info* slideInfoHeader = (dyld_cache_slide_info*)slideInfo;
- if ( slideInfoHeader != nullptr ) {
- if ( slideInfoHeader->version == 2 ) {
- const dyld_cache_slide_info2* slideHeader = (dyld_cache_slide_info2*)slideInfo;
- const uint32_t page_size = slideHeader->page_size;
- const uint16_t* page_starts = (uint16_t*)((long)(slideInfo) + slideHeader->page_starts_offset);
- const uint16_t* page_extras = (uint16_t*)((long)(slideInfo) + slideHeader->page_extras_offset);
- for (int i=0; i < slideHeader->page_starts_count; ++i) {
- uint8_t* page = (uint8_t*)(long)(dataPagesStart + (page_size*i));
- uint16_t pageEntry = page_starts[i];
- //dyld::log("page[%d]: page_starts[i]=0x%04X\n", i, pageEntry);
- if ( pageEntry == DYLD_CACHE_SLIDE_PAGE_ATTR_NO_REBASE )
- continue;
- if ( pageEntry & DYLD_CACHE_SLIDE_PAGE_ATTR_EXTRA ) {
- uint16_t chainIndex = (pageEntry & 0x3FFF);
- bool done = false;
- while ( !done ) {
- uint16_t pInfo = page_extras[chainIndex];
- uint16_t pageStartOffset = (pInfo & 0x3FFF)*4;
- //dyld::log(" chain[%d] pageOffset=0x%03X\n", chainIndex, pageStartOffset);
- rebaseChainV2(page, pageStartOffset, results->slide, slideHeader);
- done = (pInfo & DYLD_CACHE_SLIDE_PAGE_ATTR_END);
- ++chainIndex;
- }
- }
- else {
- uint32_t pageOffset = pageEntry * 4;
- //dyld::log(" start pageOffset=0x%03X\n", pageOffset);
- rebaseChainV2(page, pageOffset, results->slide, slideHeader);
- }
- }
- }
-#if __LP64__
- else if ( slideInfoHeader->version == 3 ) {
- const dyld_cache_slide_info3* slideHeader = (dyld_cache_slide_info3*)slideInfo;
- const uint32_t pageSize = slideHeader->page_size;
- for (int i=0; i < slideHeader->page_starts_count; ++i) {
- uint8_t* page = (uint8_t*)(dataPagesStart + (pageSize*i));
- uint64_t delta = slideHeader->page_starts[i];
- if ( delta == DYLD_CACHE_SLIDE_V3_PAGE_ATTR_NO_REBASE )
- continue;
- delta = delta/sizeof(uint64_t); // initial offset is byte based
- dyld_cache_slide_pointer3* loc = (dyld_cache_slide_pointer3*)page;
- do {
- loc += delta;
- delta = loc->plain.offsetToNextPointer;
- if ( loc->auth.authenticated ) {
-#if __has_feature(ptrauth_calls)
- uint64_t target = info.sharedRegionStart + loc->auth.offsetFromSharedCacheBase + results->slide;
- MachOLoaded::ChainedFixupPointerOnDisk ptr;
- ptr.raw = *((uint64_t*)loc);
- loc->raw = ptr.signPointer(loc, target);
-#else
- results->errorMessage = "invalid pointer kind in cache file";
- return false;
-#endif
- }
- else {
- loc->raw = MachOLoaded::ChainedFixupPointerOnDisk::signExtend51(loc->plain.pointerValue) + results->slide;
- }
- } while (delta != 0);
- }
- }
-#else
- else if ( slideInfoHeader->version == 4 ) {
- const dyld_cache_slide_info4* slideHeader = (dyld_cache_slide_info4*)slideInfo;
- const uint32_t page_size = slideHeader->page_size;
- const uint16_t* page_starts = (uint16_t*)((long)(slideInfo) + slideHeader->page_starts_offset);
- const uint16_t* page_extras = (uint16_t*)((long)(slideInfo) + slideHeader->page_extras_offset);
- for (int i=0; i < slideHeader->page_starts_count; ++i) {
- uint8_t* page = (uint8_t*)(long)(dataPagesStart + (page_size*i));
- uint16_t pageEntry = page_starts[i];
- //dyld::log("page[%d]: page_starts[i]=0x%04X\n", i, pageEntry);
- if ( pageEntry == DYLD_CACHE_SLIDE4_PAGE_NO_REBASE )
- continue;
- if ( pageEntry & DYLD_CACHE_SLIDE4_PAGE_USE_EXTRA ) {
- uint16_t chainIndex = (pageEntry & DYLD_CACHE_SLIDE4_PAGE_INDEX);
- bool done = false;
- while ( !done ) {
- uint16_t pInfo = page_extras[chainIndex];
- uint16_t pageStartOffset = (pInfo & DYLD_CACHE_SLIDE4_PAGE_INDEX)*4;
- //dyld::log(" chain[%d] pageOffset=0x%03X\n", chainIndex, pageStartOffset);
- rebaseChainV4(page, pageStartOffset, results->slide, slideHeader);
- done = (pInfo & DYLD_CACHE_SLIDE4_PAGE_EXTRA_END);
- ++chainIndex;
- }
- }
- else {
- uint32_t pageOffset = pageEntry * 4;
- //dyld::log(" start pageOffset=0x%03X\n", pageOffset);
- rebaseChainV4(page, pageOffset, results->slide, slideHeader);
- }
- }
- }
-#endif // LP64
- else {
- results->errorMessage = "invalid slide info in cache file";
- return false;
- }
- }
- return true;
-}
-
-static bool reuseExistingCache(const SharedCacheOptions& options, SharedCacheLoadInfo* results)
-{
- uint64_t cacheBaseAddress;
-#if __i386__
- if ( syscall(294, &cacheBaseAddress) == 0 ) {
-#else
- if ( __shared_region_check_np(&cacheBaseAddress) == 0 ) {
-#endif
- const DyldSharedCache* existingCache = (DyldSharedCache*)cacheBaseAddress;
- if ( validMagic(options, existingCache) ) {
- const dyld_cache_mapping_info* const fileMappings = (dyld_cache_mapping_info*)(cacheBaseAddress + existingCache->header.mappingOffset);
- results->loadAddress = existingCache;
- results->slide = (long)(cacheBaseAddress - fileMappings[0].address);
- // we don't know the path this cache was previously loaded from, assume default
- getCachePath(options, sizeof(results->path), results->path);
- if ( options.verbose ) {
- const shared_file_mapping_np* const mappings = (shared_file_mapping_np*)(cacheBaseAddress + existingCache->header.mappingOffset);
- dyld::log("re-using existing shared cache (%s):\n", results->path);
- shared_file_mapping_np slidMappings[3];
- for (int i=0; i < 3; ++i) {
- slidMappings[i] = mappings[i];
- slidMappings[i].sfm_address += results->slide;
- }
- verboseSharedCacheMappings(slidMappings);
- }
- }
- else {
- results->errorMessage = "existing shared cache in memory is not compatible";
- }
- return true;
- }
- return false;
-}
-
-static long pickCacheASLR(CacheInfo& info)
-{
- // choose new random slide
-#if __IPHONE_OS_VERSION_MIN_REQUIRED
- // <rdar://problem/20848977> change shared cache slide for 32-bit arm to always be 16k aligned
- long slide = ((arc4random() % info.maxSlide) & (-16384));
-#else
- long slide = ((arc4random() % info.maxSlide) & (-4096));
-#endif
-
- // <rdar://problem/32031197> respect -disable_aslr boot-arg
- if ( dyld3::bootArgsContains("-disable_aslr") )
- slide = 0;
-
- // update mappings
- for (uint32_t i=0; i < 3; ++i) {
- info.mappings[i].sfm_address += slide;
- }
-
- return slide;
-}
-
-static bool mapCacheSystemWide(const SharedCacheOptions& options, SharedCacheLoadInfo* results)
-{
- CacheInfo info;
- if ( !preflightCacheFile(options, results, &info) )
- return false;
-
- const dyld_cache_slide_info2* slideInfo = nullptr;
- if ( info.slideInfoSize != 0 ) {
- results->slide = pickCacheASLR(info);
- slideInfo = (dyld_cache_slide_info2*)(info.slideInfoAddressUnslid + results->slide);
- }
-
- int result = __shared_region_map_and_slide_np(info.fd, 3, info.mappings, results->slide, slideInfo, info.slideInfoSize);
- ::close(info.fd);
- if ( result == 0 ) {
- results->loadAddress = (const DyldSharedCache*)(info.mappings[0].sfm_address);
- }
- else {
- // could be another process beat us to it
- if ( reuseExistingCache(options, results) )
- return true;
- // if cache does not exist, then really is an error
- if ( results->errorMessage == nullptr )
- results->errorMessage = "syscall to map cache into shared region failed";
- return false;
- }
-
- if ( options.verbose ) {
- dyld::log("mapped dyld cache file system wide: %s\n", results->path);
- verboseSharedCacheMappings(info.mappings);
- }
- return true;
-}
-#endif // TARGET_IPHONE_SIMULATOR
-
-static bool mapCachePrivate(const SharedCacheOptions& options, SharedCacheLoadInfo* results)
-{
- // open and validate cache file
- CacheInfo info;
- if ( !preflightCacheFile(options, results, &info) )
- return false;
-
- // compute ALSR slide
- results->slide = 0;
-#if !TARGET_IPHONE_SIMULATOR // simulator caches do not support sliding
- if ( info.slideInfoSize != 0 ) {
- results->slide = pickCacheASLR(info);
- }
-#endif
- results->loadAddress = (const DyldSharedCache*)(info.mappings[0].sfm_address);
-
- // remove the shared region sub-map
- vm_deallocate(mach_task_self(), (vm_address_t)info.sharedRegionStart, (vm_size_t)info.sharedRegionSize);
-
- // map cache just for this process with mmap()
- for (int i=0; i < 3; ++i) {
- void* mmapAddress = (void*)(uintptr_t)(info.mappings[i].sfm_address);
- size_t size = (size_t)(info.mappings[i].sfm_size);
- //dyld::log("dyld: mapping address %p with size 0x%08lX\n", mmapAddress, size);
- int protection = 0;
- if ( info.mappings[i].sfm_init_prot & VM_PROT_EXECUTE )
- protection |= PROT_EXEC;
- if ( info.mappings[i].sfm_init_prot & VM_PROT_READ )
- protection |= PROT_READ;
- if ( info.mappings[i].sfm_init_prot & VM_PROT_WRITE )
- protection |= PROT_WRITE;
- off_t offset = info.mappings[i].sfm_file_offset;
- if ( ::mmap(mmapAddress, size, protection, MAP_FIXED | MAP_PRIVATE, info.fd, offset) != mmapAddress ) {
- // failed to map some chunk of this shared cache file
- // clear shared region
- vm_deallocate(mach_task_self(), (vm_address_t)info.sharedRegionStart, (vm_size_t)info.sharedRegionSize);
- // return failure
- results->loadAddress = nullptr;
- results->errorMessage = "could not mmap() part of dyld cache";
- return false;
- }
- }
-
-#if TARGET_IPHONE_SIMULATOR // simulator caches do not support sliding
- return true;
-#else
- bool success = rebaseDataPages(options.verbose, info, results);
-
- if ( options.verbose ) {
- dyld::log("mapped dyld cache file private to process (%s):\n", results->path);
- verboseSharedCacheMappings(info.mappings);
- }
- return success;
-#endif
-}
-
-
-
-bool loadDyldCache(const SharedCacheOptions& options, SharedCacheLoadInfo* results)
-{
- results->loadAddress = 0;
- results->slide = 0;
- results->errorMessage = nullptr;
-
-#if TARGET_IPHONE_SIMULATOR
- // simulator only supports mmap()ing cache privately into process
- return mapCachePrivate(options, results);
-#else
- if ( options.forcePrivate ) {
- // mmap cache into this process only
- return mapCachePrivate(options, results);
- }
- else {
- // fast path: when cache is already mapped into shared region
- bool hasError = false;
- if ( reuseExistingCache(options, results) ) {
- hasError = (results->errorMessage != nullptr);
- } else {
- // slow path: this is first process to load cache
- hasError = mapCacheSystemWide(options, results);
- }
- return hasError;
- }
-#endif
-}
-
-
-bool findInSharedCacheImage(const SharedCacheLoadInfo& loadInfo, const char* dylibPathToFind, SharedCacheFindDylibResults* results)
-{
- if ( loadInfo.loadAddress == nullptr )
- return false;
-
- if ( loadInfo.loadAddress->header.formatVersion != dyld3::closure::kFormatVersion ) {
- // support for older cache with a different Image* format
-#if __IPHONE_OS_VERSION_MIN_REQUIRED
- uint64_t hash = 0;
- for (const char* s=dylibPathToFind; *s != '\0'; ++s)
- hash += hash*4 + *s;
-#endif
- const dyld_cache_image_info* const start = (dyld_cache_image_info*)((uint8_t*)loadInfo.loadAddress + loadInfo.loadAddress->header.imagesOffset);
- const dyld_cache_image_info* const end = &start[loadInfo.loadAddress->header.imagesCount];
- for (const dyld_cache_image_info* p = start; p != end; ++p) {
-#if __IPHONE_OS_VERSION_MIN_REQUIRED
- // on iOS, inode is used to hold hash of path
- if ( (p->modTime == 0) && (p->inode != hash) )
- continue;
-#endif
- const char* aPath = (char*)loadInfo.loadAddress + p->pathFileOffset;
- if ( strcmp(aPath, dylibPathToFind) == 0 ) {
- results->mhInCache = (const mach_header*)(p->address+loadInfo.slide);
- results->pathInCache = aPath;
- results->slideInCache = loadInfo.slide;
- results->image = nullptr;
- return true;
- }
- }
- return false;
- }
-
- const dyld3::closure::ImageArray* images = loadInfo.loadAddress->cachedDylibsImageArray();
- results->image = nullptr;
- uint32_t imageIndex;
- if ( loadInfo.loadAddress->hasImagePath(dylibPathToFind, imageIndex) ) {
- results->image = images->imageForNum(imageIndex+1);
- }
- #if __MAC_OS_X_VERSION_MIN_REQUIRED
- else {
- // <rdar://problem/32740215> handle symlink to cached dylib
- if ( loadInfo.loadAddress->header.dylibsExpectedOnDisk ) {
- struct stat statBuf;
- if ( dyld::my_stat(dylibPathToFind, &statBuf) == 0 ) {
- // on macOS we store the inode and mtime of each dylib in the cache in the dyld_cache_image_info array
- const dyld_cache_image_info* const start = (dyld_cache_image_info*)((uint8_t*)loadInfo.loadAddress + loadInfo.loadAddress->header.imagesOffset);
- const dyld_cache_image_info* const end = &start[loadInfo.loadAddress->header.imagesCount];
- for (const dyld_cache_image_info* p = start; p != end; ++p) {
- if ( (p->inode == statBuf.st_ino) && (p->modTime == statBuf.st_mtime) ) {
- imageIndex = (uint32_t)(p - start);
- results->image = images->imageForNum(imageIndex+1);
- break;
- }
- }
- }
- }
- else {
- char resolvedPath[PATH_MAX];
- if ( realpath(dylibPathToFind, resolvedPath) != nullptr ) {
- if ( loadInfo.loadAddress->hasImagePath(resolvedPath, imageIndex) ) {
- results->image = images->imageForNum(imageIndex+1);
- }
- }
- }
- }
-#endif
- if ( results->image == nullptr )
- return false;
-
- results->mhInCache = (const mach_header*)((uintptr_t)loadInfo.loadAddress + results->image->cacheOffset());
- results->pathInCache = results->image->path();
- results->slideInCache = loadInfo.slide;
- return true;
-}
-
-
-bool pathIsInSharedCacheImage(const SharedCacheLoadInfo& loadInfo, const char* dylibPathToFind)
-{
- if ( (loadInfo.loadAddress == nullptr) || (loadInfo.loadAddress->header.formatVersion != closure::kFormatVersion) )
- return false;
-
- uint32_t imageIndex;
- return loadInfo.loadAddress->hasImagePath(dylibPathToFind, imageIndex);
-}
-
-
-} // namespace dyld3
-