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1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 | /* * 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 <TargetConditionals.h> #if !TARGET_OS_EXCLAVEKIT #include <stdint.h> #include <string.h> #include <unistd.h> #include <errno.h> #include <fcntl.h> #include <libgen.h> #include <sys/param.h> #include <sys/types.h> #include <sys/stat.h> #include <sys/fsgetpath.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 <optional> #include <Availability.h> #include <TargetConditionals.h> #include <System/mach/dyld_pager.h> #include "Defines.h" #include "dyld_cache_format.h" #include "SharedCacheRuntime.h" #include "DyldRuntimeState.h" #include "Utils.h" #define ENABLE_DYLIBS_TO_OVERRIDE_CACHE_SIZE 1024 #define MAX_SUBCACHES 128 #define SHARED_CACHE_PATH_MAX 256 // 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); extern "C" int __shared_region_map_and_slide_2_np(uint32_t files_count, const shared_file_np files[], uint32_t mappings_count, const shared_file_mapping_slide_np mappings[]); #ifndef VM_PROT_NOAUTH #define VM_PROT_NOAUTH 0x40 /* must not interfere with normal prot assignments */ #endif #ifndef VM_PROT_TPRO #define VM_PROT_TPRO 0x200 /* must not interfere with normal prot assignments */ #endif namespace dyld3 { struct CacheInfo { shared_file_mapping_slide_np mappings[DyldSharedCache::MaxMappings]; uint32_t mappingsCount; bool isTranslated; bool hasSubCacheSuffixes = false; // All mappings come from the same file int fd = 0; uint64_t sharedRegionStart; uint64_t sharedRegionSize; uint64_t maxSlide; uint32_t cacheFileCount; uint64_t dynamicConfigAddress; uint64_t dynamicConfigMaxSize; }; #if __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 __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 #if TARGET_OS_OSX static bool getMacOSCachePath(int cacheDirFD, bool useHaswell, char filePathBuffer[SHARED_CACHE_PATH_MAX]) { #if __x86_64__ if ( useHaswell ) { struct stat haswellStatBuf; strlcpy(filePathBuffer, DYLD_SHARED_CACHE_BASE_NAME ARCH_NAME_H, SHARED_CACHE_PATH_MAX); if ( dyld3::fstatat(cacheDirFD, filePathBuffer, &haswellStatBuf, 0) == 0 ) return true; } #endif struct stat statBuf; strlcpy(filePathBuffer, DYLD_SHARED_CACHE_BASE_NAME ARCH_NAME, SHARED_CACHE_PATH_MAX); if ( dyld3::fstatat(cacheDirFD, filePathBuffer, &statBuf, 0) == 0 ) return true; return false; } #endif // TARGET_OS_OSX static bool getCachePath(int cacheDirFD, bool useHaswell, bool preferCustomerCache, bool forceDevCache, char pathBuffer[SHARED_CACHE_PATH_MAX], char basePathBuffer[SHARED_CACHE_PATH_MAX]) { #if TARGET_OS_OSX if ( getMacOSCachePath(cacheDirFD, useHaswell, pathBuffer) ) { strlcpy(basePathBuffer, pathBuffer, SHARED_CACHE_PATH_MAX); return true; } #else // TARGET_OS_OSX strlcpy(pathBuffer, DYLD_SHARED_CACHE_BASE_NAME ARCH_NAME, SHARED_CACHE_PATH_MAX); strlcpy(basePathBuffer, pathBuffer, SHARED_CACHE_PATH_MAX); #if TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR // use .development cache if it exists if ( preferCustomerCache) { return true; } // If only one or the other caches exists, then use the one we have char potentialDevPath[SHARED_CACHE_PATH_MAX]; strlcpy(potentialDevPath, pathBuffer, SHARED_CACHE_PATH_MAX); strlcat(potentialDevPath, DYLD_SHARED_CACHE_DEVELOPMENT_EXT, PATH_MAX); struct stat devCacheStatBuf; bool devCacheExists = (dyld3::fstatat(cacheDirFD, potentialDevPath, &devCacheStatBuf, 0) == 0); if ( !devCacheExists ) { // If the dev cache doesn't exist, then use the customer cache return true; } struct stat optCacheStatBuf; bool optCacheExists = (dyld3::fstatat(cacheDirFD, pathBuffer, &optCacheStatBuf, 0) == 0); if ( !optCacheExists || forceDevCache ) { // If the customer cache doesn't exist (or dyld_flags=4), then use the development cache strlcpy(pathBuffer, potentialDevPath, SHARED_CACHE_PATH_MAX); return true; } // Finally, check for the sentinels struct stat enableStatBuf; //struct stat sentinelStatBuf; bool enableFileExists = (dyld3::stat(IPHONE_DYLD_SHARED_CACHE_DIR "enable-dylibs-to-override-cache", &enableStatBuf) == 0); // FIXME: rdar://problem/59813537 Re-enable once automation is updated to use boot-arg bool sentinelFileExists = false; //bool sentinelFileExists = (dyld3::stat(MACOSX_MRM_DYLD_SHARED_CACHE_DIR "enable_development_mode", &sentinelStatBuf) == 0); if ( enableFileExists && (enableStatBuf.st_size < ENABLE_DYLIBS_TO_OVERRIDE_CACHE_SIZE) ) { // if the old enable file exists, use the development cache strlcat(pathBuffer, DYLD_SHARED_CACHE_DEVELOPMENT_EXT, SHARED_CACHE_PATH_MAX); return true; } if ( sentinelFileExists ) { // If the new sentinel exists, then use the development cache strlcat(pathBuffer, DYLD_SHARED_CACHE_DEVELOPMENT_EXT, SHARED_CACHE_PATH_MAX); return true; } #endif #endif //!TARGET_OS_OSX return false; } // <rdar://problem/10111032> wrap calls to stat() with check for EAGAIN static int openat(int fd, const char* path) { int result; do { result = ::openat(fd, path, O_RDONLY, 0); } while ((result == -1) && ((errno == EAGAIN) || (errno == EINTR))); return result; } static int openMainSharedCacheFile(const SharedCacheOptions& options, char basePath[SHARED_CACHE_PATH_MAX]) { char path[SHARED_CACHE_PATH_MAX]; getCachePath(options.cacheDirFD, options.useHaswell, options.preferCustomerCache, options.forceDevCache, path, basePath); int fd = openat(options.cacheDirFD, path); if ( fd != -1 ) { return fd; } return -1; } static int openSubSharedCacheFile(int cacheDirFD, char basePath[SHARED_CACHE_PATH_MAX], const char* suffix) { char path[SHARED_CACHE_PATH_MAX]; strlcpy(path, basePath, SHARED_CACHE_PATH_MAX); strlcat(path, suffix, SHARED_CACHE_PATH_MAX); return openat(cacheDirFD, path); } 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; uint32_t platform = (uint32_t)options.platform; if ( cache->header.platform != platform ) { // rdar://74501167 (Marzicaches don't work in private mode) if ( cache->header.altPlatform != 0 && ( cache->header.altPlatform == platform ) ) { return true; } return false; } #if TARGET_OS_SIMULATOR if ( cache->header.simulator == 0 ) return false; #else if ( cache->header.simulator != 0 ) return false; #endif return true; } static void verboseSharedCacheMappings(const DyldSharedCache* dyldCache) { intptr_t slide = dyldCache->slide(); dyldCache->forEachRange(^(const char *mappingName, uint64_t unslidVMAddr, uint64_t vmSize, uint32_t cacheFileIndex, uint64_t fileOffset, uint32_t initProt, uint32_t maxProt, bool& stopRange) { dyld4::console(" 0x%08llX->0x%08llX init=%x, max=%x %s\n", unslidVMAddr + slide, unslidVMAddr + slide + vmSize - 1, initProt, maxProt, mappingName); }); } static bool preflightCacheFile(const SharedCacheOptions& options, SharedCacheLoadInfo* results, CacheInfo* info, int fd, std::array<char[32], MAX_SUBCACHES>* subCacheSuffixes) { struct stat cacheStatBuf; if ( ::fstat(fd, &cacheStatBuf) != 0 ) { results->errorMessage = "shared cache file stat() failed"; ::close(fd); return false; } size_t cacheFileLength = (size_t)(cacheStatBuf.st_size); results->FSID = cacheStatBuf.st_dev; results->FSObjID = cacheStatBuf.st_ino; // sanity check header and mappings uint8_t firstPage[0x4000]; if ( ::pread(fd, firstPage, sizeof(firstPage), 0) != sizeof(firstPage) ) { results->errorMessage = "shared cache file pread() failed"; ::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 == 0) || (cache->header.mappingCount > DyldSharedCache::MaxMappings) /*|| (cache->header.mappingOffset > 0x168)*/ ) { 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]; const dyld_cache_mapping_info* textMapping = &fileMappings[0]; std::optional<const dyld_cache_mapping_info*> linkeditMapping; // Split caches may not have __DATA/__LINKEDIT if ( cache->header.mappingCount > 1 ) { // The last mapping should be __LINKEDIT, so long as we have > 1 mapping in total linkeditMapping = &fileMappings[cache->header.mappingCount - 1]; } if ( textMapping->fileOffset != 0 ) { results->errorMessage = "shared cache text file offset is invalid"; } else if ( (cache->header.codeSignatureOffset + cache->header.codeSignatureSize) != cacheFileLength ) { results->errorMessage = "shared cache code signature size is invalid"; } else if ( linkeditMapping.has_value() && (linkeditMapping.value()->maxProt != VM_PROT_READ) ) { results->errorMessage = "shared cache linkedit permissions are invalid"; } // Regular cache files have TEXT first // The LINKEDIT only cache is allowed to have raed-only TEXT as it contains no code if ( linkeditMapping.has_value() ) { if ( (textMapping->maxProt != (VM_PROT_READ|VM_PROT_EXECUTE)) && (textMapping->maxProt != VM_PROT_READ) ) { results->errorMessage = "shared cache text permissions are invalid"; } } else { if ( textMapping->maxProt != (VM_PROT_READ|VM_PROT_EXECUTE) ) { results->errorMessage = "shared cache text permissions are invalid"; } } if ( results->errorMessage != nullptr ) { ::close(fd); return false; } // Check mappings don't overlap for (unsigned i = 0; i != (cache->header.mappingCount - 1); ++i) { if ( ((fileMappings[i].address + fileMappings[i].size) > fileMappings[i + 1].address) || ((fileMappings[i].fileOffset + fileMappings[i].size) != fileMappings[i + 1].fileOffset) ) { results->errorMessage = "shared cache mappings overlap"; break; } } if ( results->errorMessage != nullptr ) { ::close(fd); return false; } if ( results->errorMessage != nullptr ) { ::close(fd); return false; } // Make this check real in the new world. #ifdef NOT_NOW if ( (textMapping->address != cache->header.sharedRegionStart) || ((linkeditMapping->address + linkeditMapping->size) > (cache->header.sharedRegionStart+cache->header.sharedRegionSize)) ) { results->errorMessage = "shared cache file mapping addressses invalid"; ::close(fd); return false; } #endif // 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->mappingsCount = cache->header.mappingCount; // We have to emit the mapping for the __LINKEDIT before the slid mappings // This is so that the kernel has already mapped __LINKEDIT in to its address space // for when it copies the slid info for each __DATA mapping for (int i=0; i < cache->header.mappingCount; ++i) { uint64_t slideInfoFileOffset = 0; uint64_t slideInfoFileSize = 0; vm_prot_t authProt = 0; vm_prot_t initProt = fileMappings[i].initProt; vm_prot_t maxProt = fileMappings[i].maxProt; if ( cache->header.mappingOffset <= __offsetof(dyld_cache_header, mappingWithSlideOffset) ) { // Old cache without the new slid mappings if ( i == 1 ) { // Add slide info to the __DATA mapping slideInfoFileOffset = cache->header.slideInfoOffsetUnused; slideInfoFileSize = cache->header.slideInfoSizeUnused; // Don't set auth prot to anything interseting on the old mapppings authProt = 0; } } else { // New cache where each mapping has a corresponding slid mapping const dyld_cache_mapping_and_slide_info* slidableMappings = (const dyld_cache_mapping_and_slide_info*)&firstPage[cache->header.mappingWithSlideOffset]; slideInfoFileOffset = slidableMappings[i].slideInfoFileOffset; slideInfoFileSize = slidableMappings[i].slideInfoFileSize; if ( (slidableMappings[i].flags & DYLD_CACHE_MAPPING_AUTH_DATA) == 0 ) authProt = VM_PROT_NOAUTH; if ( (slidableMappings[i].flags & DYLD_CACHE_MAPPING_CONST_DATA) != 0 ) { // The cache was built with __DATA_CONST being read-only. We can override that with a boot-arg // TPRO might not be enabled for this process (unlikely) but could be for others. Allow // the kernel to determine whether to apply the appropriate flags if ( !options.enableReadOnlyDataConst ) initProt |= VM_PROT_WRITE; else maxProt |= VM_PROT_TPRO; } } // Add a file for each mapping info->fd = fd; info->mappings[i].sms_address = fileMappings[i].address; info->mappings[i].sms_size = fileMappings[i].size; info->mappings[i].sms_file_offset = fileMappings[i].fileOffset; info->mappings[i].sms_slide_size = 0; info->mappings[i].sms_slide_start = 0; info->mappings[i].sms_max_prot = maxProt; info->mappings[i].sms_init_prot = initProt; if ( slideInfoFileSize != 0 ) { uint64_t offsetInLinkEditRegion = (slideInfoFileOffset - linkeditMapping.value()->fileOffset); info->mappings[i].sms_slide_start = (user_addr_t)(linkeditMapping.value()->address + offsetInLinkEditRegion); info->mappings[i].sms_slide_size = (user_addr_t)slideInfoFileSize; info->mappings[i].sms_init_prot |= (VM_PROT_SLIDE | authProt); info->mappings[i].sms_max_prot |= (VM_PROT_SLIDE | authProt); } } if ( cache->header.subCacheArrayCount >= MAX_SUBCACHES ) { results->errorMessage = "shared cache file subcache count exceeds limit"; ::close(fd); return false; } if ( (cache->header.subCacheArrayCount != 0) && (subCacheSuffixes == nullptr) ) { results->errorMessage = "no shared cache subcache indices"; ::close(fd); return false; } info->hasSubCacheSuffixes = (cache->header.mappingOffset > __offsetof(dyld_cache_header, cacheSubType)); if ( info->hasSubCacheSuffixes ) { uint8_t subCacheArray[MAX_SUBCACHES*sizeof(dyld_subcache_entry)]; if ( ::pread(fd, subCacheArray, sizeof(subCacheArray), cache->header.subCacheArrayOffset) != sizeof(subCacheArray) ) { results->errorMessage = "shared cache file pread() failed, could not read subcache entries"; ::close(fd); return false; } const dyld_subcache_entry* subCacheEntries = (dyld_subcache_entry*)subCacheArray; for (uint32_t i = 0; i != cache->header.subCacheArrayCount; ++i) { memcpy(&((*subCacheSuffixes)[i]), subCacheEntries[i].fileSuffix, 32); } } info->sharedRegionStart = cache->header.sharedRegionStart; info->sharedRegionSize = cache->header.sharedRegionSize; info->maxSlide = cache->header.maxSlide; info->isTranslated = options.isTranslated; info->cacheFileCount = cache->numSubCaches() + 1; info->dynamicConfigAddress = cache->header.sharedRegionStart + cache->header.dynamicDataOffset; info->dynamicConfigMaxSize = cache->header.dynamicDataMaxSize; bool isUniversal = cache->header.cacheType == kDyldSharedCacheTypeUniversal; bool isUniversalDev = isUniversal && cache->header.cacheSubType == kDyldSharedCacheTypeDevelopment; results->development = cache->header.cacheType == kDyldSharedCacheTypeDevelopment || isUniversalDev; return true; } static bool preflightMainCacheFile(const SharedCacheOptions& options, SharedCacheLoadInfo* results, CacheInfo* info, char basePath[SHARED_CACHE_PATH_MAX], std::array<char[32], MAX_SUBCACHES>* subCacheSuffixes) { // find and open shared cache file int fd = openMainSharedCacheFile(options, basePath); if ( fd == -1 ) { if ( errno == ENOENT ) { results->cacheFileFound = false; results->errorMessage = "no shared cache file"; } else results->errorMessage = "shared cache file open() failed"; return false; } results->cacheFileFound = true; return preflightCacheFile(options, results, info, fd, subCacheSuffixes); } #if !TARGET_OS_SIMULATOR 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; } } #endif #if !__LP64__ && !TARGET_OS_SIMULATOR 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 bool preflightSubCacheFile(const SharedCacheOptions& options, SharedCacheLoadInfo* results, CacheInfo* info, char basePath[SHARED_CACHE_PATH_MAX], const char* suffix) { // find and open shared cache file int fd = openSubSharedCacheFile(options.cacheDirFD, basePath, suffix); if ( fd == -1 ) { if ( errno == ENOENT ) { results->cacheFileFound = false; results->errorMessage = "no shared cache file"; } else results->errorMessage = "shared cache file open() failed"; return false; } results->cacheFileFound = true; return preflightCacheFile(options, results, info, fd, nullptr); } static void configureDynamicData(void* address, SharedCacheLoadInfo* results) { dyld_cache_dynamic_data_header* dynamicData = (dyld_cache_dynamic_data_header*)address; strlcpy(dynamicData->magic, DYLD_SHARED_CACHE_DYNAMIC_DATA_MAGIC, 16); dynamicData->fsId = results->FSID; dynamicData->fsObjId = results->FSObjID; } static void closeSplitCacheFiles(CacheInfo infoArray[16], uint32_t numFiles) { for ( unsigned i = 0; i < numFiles; ++i ) { int subCachefd = infoArray[i].fd; if ( subCachefd != -1 ) ::close(subCachefd); } } #if !TARGET_OS_SIMULATOR // update all __DATA pages with slide info static bool rebaseDataPages(bool isVerbose, const dyld_cache_slide_info* slideInfo, const uint8_t *dataPagesStart, SharedCacheLoadInfo* results) { const dyld_cache_slide_info* slideInfoHeader = 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]; //dyld4::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; //dyld4::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]; //dyld::log("page[%d]: page_starts[i]=0x%04X\n", i, delta); 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 = slideHeader->auth_value_add + loc->auth.offsetFromSharedCacheBase + results->slide; MachOLoaded::ChainedFixupPointerOnDisk ptr; ptr.raw64 = *((uint64_t*)loc); loc->raw = ptr.arm64e.signPointer(loc, target); #else results->errorMessage = "invalid pointer kind in cache file"; return false; #endif } else { MachOLoaded::ChainedFixupPointerOnDisk ptr; ptr.raw64 = *((uint64_t*)loc); loc->raw = ptr.arm64e.unpackTarget() + results->slide; } } while (delta != 0); } } else if ( slideInfoHeader->version == 5 ) { #if __has_feature(ptrauth_calls) const dyld_cache_slide_info5* slideHeader = (dyld_cache_slide_info5*)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]; //dyld::log("page[%d]: page_starts[i]=0x%04X\n", i, delta); if ( delta == DYLD_CACHE_SLIDE_V5_PAGE_ATTR_NO_REBASE ) continue; delta = delta/sizeof(uint64_t); // initial offset is byte based dyld_cache_slide_pointer5* loc = (dyld_cache_slide_pointer5*)page; do { loc += delta; delta = loc->regular.next; MachOLoaded::ChainedFixupPointerOnDisk ptr; ptr.raw64 = *((uint64_t*)loc); uint64_t target = slideHeader->value_add + loc->regular.runtimeOffset + results->slide; if ( loc->auth.auth ) { loc->raw = ptr.cache64e.signPointer(loc, target); } else { loc->raw = target | ptr.cache64e.high8(); } } while (delta != 0); } #else results->errorMessage = "invalid pointer kind in cache file"; return false; #endif } #else else if ( slideInfoHeader->version == 1 ) { const dyld_cache_slide_info* slideHeader = (dyld_cache_slide_info*)slideInfo; const uint32_t page_size = 4096; const dyld_cache_slide_info_entry* entries = (dyld_cache_slide_info_entry*)((char*)slideHeader + slideHeader->entries_offset); const uint16_t* tocs = (uint16_t*)((char*)slideHeader + slideHeader->toc_offset); for(int i=0; i < slideHeader->toc_count; ++i) { const dyld_cache_slide_info_entry* entry = &entries[tocs[i]]; uint8_t* page = (uint8_t*)(long)(dataPagesStart + (page_size * i)); for(int j = 0; j < slideHeader->entries_size; ++j) { uint8_t bitmask = entry->bits[j]; for (unsigned k = 0; k != 8; ++k) { if ( bitmask & (1 << k) ) { uint32_t pageOffset = ((j * 8) + k) * 4; uint32_t* loc = (uint32_t*)(page + pageOffset); *loc = *loc + results->slide; } } } } } 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 ( __shared_region_check_np(&cacheBaseAddress) == 0 ) { const DyldSharedCache* existingCache = (DyldSharedCache*)cacheBaseAddress; if ( validMagic(options, existingCache) ) { results->loadAddress = existingCache; results->slide = (long)existingCache->slide(); bool isUniversal = existingCache->header.cacheType == kDyldSharedCacheTypeUniversal; bool isUniversalDev = isUniversal && existingCache->header.cacheSubType == kDyldSharedCacheTypeDevelopment; results->development = existingCache->header.cacheType == kDyldSharedCacheTypeDevelopment || isUniversalDev; dyld_cache_dynamic_data_header* dynamicData = (dyld_cache_dynamic_data_header*)((uintptr_t)results->loadAddress + existingCache->header.dynamicDataOffset); if (strncmp((char*)dynamicData, DYLD_SHARED_CACHE_DYNAMIC_DATA_MAGIC, 16) == 0) { results->FSID = dynamicData->fsId; results->FSObjID = dynamicData->fsObjId; } else { dyld4::console("mapped cache does not contain dynamic config data\n"); } if (options.verbose) { char path[MAXPATHLEN]; if (::fsgetpath(&path[0], MAXPATHLEN, (fsid_t*)(&results->FSID), results->FSObjID) > 0) { dyld4::console("re-using existing shared cache (%s):\n", path); } verboseSharedCacheMappings(existingCache); } } else { results->errorMessage = "existing shared cache in memory is not compatible"; return false; } return true; } return false; } // this has a large stack frame size, so don't inline into loadDyldCache() __attribute__((noinline)) static bool mapSplitCacheSystemWide(const SharedCacheOptions& options, SharedCacheLoadInfo* results) { CacheInfo firstFileInfo; // Try to map the first file to see how many other files we need to map. char baseSharedCachePath[SHARED_CACHE_PATH_MAX] = { 0 }; std::array<char[32], MAX_SUBCACHES> subCacheSuffixes; if ( !preflightMainCacheFile(options, results, &firstFileInfo, baseSharedCachePath, &subCacheSuffixes) ) return false; uint32_t numFiles = firstFileInfo.cacheFileCount; if ( (numFiles != 0) && !firstFileInfo.hasSubCacheSuffixes ) { results->errorMessage = "shared cache is too old, missing subcache suffixes"; return false; } CacheInfo infoArray[MAX_SUBCACHES]; for (unsigned i = 1; i < numFiles; ++i) { SharedCacheLoadInfo subCacheResults; const char* suffix = subCacheSuffixes[i-1]; if ( !preflightSubCacheFile(options, &subCacheResults, &infoArray[i], baseSharedCachePath, suffix) ) { return false; } } vm_address_t dynamicConfigData = 0; vm_size_t dynamicConfigSize = ((sizeof(dyld_cache_dynamic_data_header)+PAGE_SIZE-1) & (-PAGE_SIZE)); kern_return_t kr = vm_allocate(mach_task_self(), &dynamicConfigData, dynamicConfigSize, VM_FLAGS_ANYWHERE); if (kr != KERN_SUCCESS) { results->errorMessage = "Could not vm_allocate fixed range for dynamic config data"; return false; } configureDynamicData((void*)dynamicConfigData, results); infoArray[0] = firstFileInfo; shared_file_np files[numFiles + 1]; uint32_t totalMappings = 0; for (unsigned i = 0; i < numFiles; ++i) { files[i].sf_fd = infoArray[i].fd; uint32_t numMappings = infoArray[i].mappingsCount; files[i].sf_mappings_count = numMappings; totalMappings += numMappings; // The first cache file has the maxSlide for all subCaches. files[i].sf_slide = (i == 0) ? (uint32_t)infoArray[0].maxSlide : 0; } // Set up the dynamic config region (for now just allocate something we can test) files[numFiles] = { -1, 1, 0 }; shared_file_mapping_slide_np mappings[totalMappings + 1]; uint32_t mappingIdx = 0; if ( options.verbose ) { dyld4::console("Mapping the shared cache system wide\n"); } for (unsigned i = 0; i < numFiles; ++i) { uint32_t numMappings = infoArray[i].mappingsCount; shared_file_mapping_slide_np *segmentMappings = infoArray[i].mappings; for (unsigned j = 0; j < numMappings; ++j) { mappings[mappingIdx++] = segmentMappings[j]; } } mappings[totalMappings] = { firstFileInfo.dynamicConfigAddress, dynamicConfigSize, (mach_vm_offset_t)dynamicConfigData, 0, 0, VM_PROT_READ, VM_PROT_READ }; int ret = __shared_region_map_and_slide_2_np(numFiles + 1, files, totalMappings + 1, mappings); (void)vm_deallocate(mach_task_self(), dynamicConfigData, dynamicConfigSize); // <rdar://problem/75293466> don't leak file descriptors. closeSplitCacheFiles(infoArray, numFiles); if ( ret == 0 ) { // We don't know our own slide any more as the kernel owns it, so ask for it again now if ( reuseExistingCache(options, results) ) { return true; } } 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 ) { dyld4::console("mapped dyld cache file system wide\n"); } return true; } #endif // TARGET_OS_SIMULATOR // this has a large stack frame size, so don't inline into loadDyldCache() // Note: disable tail call optimization, otherwise tailcall may remove stack allocated blob [[clang::disable_tail_calls, clang::noinline]] static bool mapSplitCachePrivate(const SharedCacheOptions& options, SharedCacheLoadInfo* results) { CacheInfo firstFileInfo; // Try to map the first file to see how many other files we need to map. char baseSharedCachePath[SHARED_CACHE_PATH_MAX] = { 0 }; std::array<char[32], MAX_SUBCACHES> subCacheSuffixes; if ( !preflightMainCacheFile(options, results, &firstFileInfo, baseSharedCachePath, &subCacheSuffixes) ) return false; if (options.verbose) { char path[PATH_MAX]; if (::fsgetpath(&path[0], PATH_MAX, (fsid_t*)(&results->FSID), results->FSObjID) > 0) { dyld4::console("mapped dyld cache file private to process (%s):\n", path); } } uint32_t numFiles = firstFileInfo.cacheFileCount; if ( (numFiles != 0) && !firstFileInfo.hasSubCacheSuffixes ) { results->errorMessage = "shared cache is too old, missing subcache suffixes"; return false; } CacheInfo infoArray[MAX_SUBCACHES]; for (unsigned i = 1; i < numFiles; ++i) { SharedCacheLoadInfo subCacheResults; char* suffix = subCacheSuffixes[i-1]; if ( !preflightSubCacheFile(options, &subCacheResults, &infoArray[i], baseSharedCachePath, suffix) ) { return false; } if ( options.verbose ) { char pathBuffer[PATH_MAX] = { 0 }; if (::fsgetpath(&pathBuffer[0], PATH_MAX, (fsid_t*)(&subCacheResults.FSID), subCacheResults.FSObjID) > 0) { dyld4::console("mapped dyld cache file private to process (%s):\n", pathBuffer); } } } infoArray[0] = firstFileInfo; uint8_t* buffer = (uint8_t*)SHARED_REGION_BASE; uint64_t baseCacheUnslidAddress = firstFileInfo.mappings[0].sms_address; uint64_t subCacheBufferOffset = 0; // deallocate any existing system wide shared cache deallocateExistingSharedCache(); #if TARGET_OS_SIMULATOR // The simulator never slides results->slide = (long)0; #else // TODO: implement real ASLR. For now just use 0 results->slide = (long)0; #endif for (unsigned i = 0; i < numFiles; ++i) { CacheInfo& subcache = infoArray[i]; int num_mappings = subcache.mappingsCount; shared_file_mapping_slide_np* mappings = (shared_file_mapping_slide_np*)subcache.mappings; for (unsigned j = 0; j < num_mappings; ++j) { mappings[j].sms_address += results->slide; if ( mappings[j].sms_slide_size != 0 ) mappings[j].sms_slide_start += results->slide; } } results->loadAddress = (const DyldSharedCache*)(infoArray[0].mappings[0].sms_address); for (unsigned i = 0; i < numFiles; ++i) { const CacheInfo& subcache = infoArray[i]; int num_mappings = subcache.mappingsCount; const shared_file_mapping_slide_np* mappings = (shared_file_mapping_slide_np*)subcache.mappings; int cache_fd = subcache.fd; // Recompute the cache offset for the main cache and the other subcaches. subCacheBufferOffset = mappings[0].sms_address - baseCacheUnslidAddress; for (unsigned j = 0; j < num_mappings; ++j) { uint64_t mappingAddressOffset = mappings[j].sms_address - mappings[0].sms_address; int protection = 0; if ( mappings[j].sms_init_prot & VM_PROT_EXECUTE ) protection |= PROT_EXEC; if ( mappings[j].sms_init_prot & VM_PROT_READ ) protection |= PROT_READ; if ( mappings[j].sms_init_prot & VM_PROT_WRITE ) protection |= PROT_WRITE; void* mapped_cache = ::mmap((void*)(buffer + subCacheBufferOffset + mappingAddressOffset + results->slide), (size_t)mappings[j].sms_size, protection, MAP_FIXED | MAP_PRIVATE, cache_fd, mappings[j].sms_file_offset); if (mapped_cache == MAP_FAILED) { if ( results->errorMessage == nullptr ) results->errorMessage = "mmap() the shared cache region failed"; closeSplitCacheFiles(infoArray, numFiles); return false; } } } void* dynamicConfigData = (void*)(firstFileInfo.dynamicConfigAddress + results->slide); size_t dynamicConfigSize = ((sizeof(dyld_cache_dynamic_data_header)+PAGE_SIZE-1) & (-PAGE_SIZE)); if (::mmap(dynamicConfigData, dynamicConfigSize, VM_PROT_READ | VM_PROT_WRITE, MAP_ANON | MAP_FIXED | MAP_PRIVATE, -1, 0) != dynamicConfigData) { // clear shared region ::mmap((void*)((long)SHARED_REGION_BASE), SHARED_REGION_SIZE, PROT_NONE, MAP_FIXED | MAP_PRIVATE| MAP_ANON, 0, 0); // return failure results->loadAddress = nullptr; results->errorMessage = "could not mmap() dynamic config memory"; return false; } configureDynamicData(dynamicConfigData, results); ::mprotect(dynamicConfigData, dynamicConfigSize, VM_PROT_READ); if ( options.verbose ) { verboseSharedCacheMappings(results->loadAddress); } bool success = true; #if !TARGET_OS_SIMULATOR for (unsigned i = 0; i < numFiles; ++i) { CacheInfo subcache = infoArray[i]; // Change __DATA_CONST to read-write while fixup chains are applied if ( options.enableReadOnlyDataConst ) { const DyldSharedCache* subCache = (const DyldSharedCache*)(subcache.mappings[0].sms_address); subCache->forEachRegion(^(const void*, uint64_t vmAddr, uint64_t size, uint32_t initProt, uint32_t maxProt, uint64_t flags, bool& stopRegion) { if ( flags & DYLD_CACHE_MAPPING_CONST_DATA ) { ::vm_protect(mach_task_self(), (vm_address_t)vmAddr + results->slide, (vm_size_t)size, false, VM_PROT_WRITE | VM_PROT_READ | VM_PROT_COPY); } }); } // work out if this subcache can use page-in linking bool canUsePageInLinking = options.usePageInLinking; if ( canUsePageInLinking ) { uint32_t numSlidMappings = 0; for (unsigned j = 0; j < subcache.mappingsCount; ++j) { if ( subcache.mappings[j].sms_slide_size == 0 ) continue; ++numSlidMappings; const dyld_cache_slide_info* slideInfoHeader = (const dyld_cache_slide_info*)subcache.mappings[j].sms_slide_start; if ( slideInfoHeader->version != 5 ) { canUsePageInLinking = false; } } // the kernel only supports 5 regions per syscall, so any segments past that are fixed up by dyld // for now we'll just do all or nothing as its simpler, and this shouldn't come up in practice if ( numSlidMappings > 5 ) canUsePageInLinking = false; } if ( canUsePageInLinking ) { const shared_file_mapping_slide_np* mappings = (shared_file_mapping_slide_np*)subcache.mappings; struct PageInLinkingRange { mwl_region region; const char* segName; const dyld_cache_slide_info* slideInfo; }; STACK_ALLOC_OVERFLOW_SAFE_ARRAY(PageInLinkingRange, ranges, 8); for (unsigned j = 0; j < subcache.mappingsCount; ++j) { if ( subcache.mappings[j].sms_slide_size == 0 ) continue; const dyld_cache_slide_info* slideInfoHeader = (const dyld_cache_slide_info*)subcache.mappings[j].sms_slide_start; assert(slideInfoHeader->version == 5); const dyld_cache_slide_info5* slideInfo = (dyld_cache_slide_info5*)slideInfoHeader; int protection = 0; if ( mappings[j].sms_init_prot & VM_PROT_EXECUTE ) protection |= PROT_EXEC; if ( mappings[j].sms_init_prot & VM_PROT_READ ) protection |= PROT_READ; if ( mappings[j].sms_init_prot & VM_PROT_WRITE ) protection |= PROT_WRITE; PageInLinkingRange rangeInfo; rangeInfo.region.mwlr_fd = infoArray[i].fd; rangeInfo.region.mwlr_protections = protection; rangeInfo.region.mwlr_file_offset = subcache.mappings[j].sms_file_offset; rangeInfo.region.mwlr_address = subcache.mappings[j].sms_address + results->slide; rangeInfo.region.mwlr_size = slideInfo->page_size * slideInfo->page_starts_count; rangeInfo.segName = DyldSharedCache::mappingName(mappings[i].sms_max_prot, 0); rangeInfo.slideInfo = slideInfoHeader; ranges.push_back(rangeInfo); } // create blob on the stack uint32_t chainInfoSize = (uint32_t)offsetof(dyld_chained_starts_in_image, seg_info_offset[ranges.count()]); for (const PageInLinkingRange& range : ranges) { const dyld_cache_slide_info* slideInfoHeader = (const dyld_cache_slide_info*)range.slideInfo; assert(slideInfoHeader->version == 5); const dyld_cache_slide_info5* slideInfo = (dyld_cache_slide_info5*)slideInfoHeader; chainInfoSize += (uint32_t)offsetof(dyld_chained_starts_in_segment, page_start[slideInfo->page_starts_count]); chainInfoSize = (chainInfoSize + 3) & (-4); // size should always be 4-byte aligned } uint32_t bindsOffset = (sizeof(mwl_info_hdr) + chainInfoSize + 7) & (-8); // 8-byte align size_t blobAllocationSize = bindsOffset; uint8_t blobBuffer[blobAllocationSize]; bzero(blobBuffer, blobAllocationSize); mwl_info_hdr* blob = (mwl_info_hdr*)blobBuffer; blob->mwli_version = 7; blob->mwli_page_size = 0x4000; blob->mwli_pointer_format = DYLD_CHAINED_PTR_ARM64E_SHARED_CACHE; blob->mwli_binds_offset = bindsOffset; blob->mwli_binds_count = 0; blob->mwli_chains_offset = sizeof(mwl_info_hdr); blob->mwli_chains_size = chainInfoSize; blob->mwli_slide = results->slide; blob->mwli_image_address = (uintptr_t)baseCacheUnslidAddress; uint32_t offsetInChainInfo = (uint32_t)offsetof(dyld_chained_starts_in_image, seg_info_offset[ranges.count()]); uint32_t rangeIndex = 0; dyld_chained_starts_in_image* starts = (dyld_chained_starts_in_image*)((uint8_t*)blob + blob->mwli_chains_offset); starts->seg_count = (uint32_t)ranges.count(); for (const PageInLinkingRange& range : ranges) { const dyld_cache_slide_info* slideInfoHeader = (const dyld_cache_slide_info*)range.slideInfo; assert(slideInfoHeader->version == 5); const dyld_cache_slide_info5* slideInfo = (dyld_cache_slide_info5*)slideInfoHeader; starts->seg_info_offset[rangeIndex] = offsetInChainInfo; dyld_chained_starts_in_segment* startsInSegment = (dyld_chained_starts_in_segment*)&blobBuffer[blob->mwli_chains_offset + offsetInChainInfo]; startsInSegment->size = (uint32_t)offsetof(dyld_chained_starts_in_segment, page_start[slideInfo->page_starts_count]); startsInSegment->page_size = 0x4000; startsInSegment->pointer_format = DYLD_CHAINED_PTR_ARM64E_SHARED_CACHE; startsInSegment->segment_offset = range.region.mwlr_address - (blob->mwli_image_address + blob->mwli_slide); startsInSegment->max_valid_pointer = 0; startsInSegment->page_count = slideInfo->page_starts_count; for ( uint32_t pageIndex = 0; pageIndex != slideInfo->page_starts_count; ++pageIndex ) startsInSegment->page_start[pageIndex] = slideInfo->page_starts[pageIndex]; ++rangeIndex; offsetInChainInfo += startsInSegment->size; offsetInChainInfo = (offsetInChainInfo + 3) & (-4); // size should always be 4-byte aligned } STACK_ALLOC_ARRAY(mwl_region, regions, ranges.count()); for (const PageInLinkingRange& range : ranges) { regions.push_back(range.region); } if ( options.verbose ) dyld4::console("Setting up kernel page-in linking for subcache %d\n", i); int result = __map_with_linking_np(regions.data(), (uint32_t)regions.count(), blob, (uint32_t)blobAllocationSize); if ( result != 0 ) { if ( options.verbose ) dyld4::console("__map_with_linking_np(subcache %d) failed, falling back to linking in-process\n", i); canUsePageInLinking = false; } } if ( !canUsePageInLinking ) { for (unsigned j = 0; j < subcache.mappingsCount; ++j) { if ( subcache.mappings[j].sms_slide_size == 0 ) continue; const dyld_cache_slide_info* slideInfoHeader = (const dyld_cache_slide_info*)subcache.mappings[j].sms_slide_start; const uint8_t* mappingPagesStart = (const uint8_t*)subcache.mappings[j].sms_address; success &= rebaseDataPages(options.verbose, slideInfoHeader, mappingPagesStart, results); } } // Change __DATA_CONST back to read-only if ( options.enableReadOnlyDataConst ) { const DyldSharedCache* subCache = (const DyldSharedCache*)(subcache.mappings[0].sms_address); subCache->forEachRegion(^(const void*, uint64_t vmAddr, uint64_t size, uint32_t initProt, uint32_t maxProt, uint64_t flags, bool& stopRegion) { if ( flags & DYLD_CACHE_MAPPING_CONST_DATA ) { ::vm_protect(mach_task_self(), (vm_address_t)vmAddr + results->slide, (vm_size_t)size, false, VM_PROT_READ); } }); } } #endif // Put this at the end so that we still have the fd's open for the above rebase loop closeSplitCacheFiles(infoArray, numFiles); return success; } bool loadDyldCache(const SharedCacheOptions& options, SharedCacheLoadInfo* results) { bool success = false; results->loadAddress = 0; results->slide = 0; results->errorMessage = nullptr; if ( options.forcePrivate ) { // mmap cache into this process only success = mapSplitCachePrivate(options, results); } else { #if !TARGET_OS_SIMULATOR // fast path: when cache is already mapped into shared region if ( reuseExistingCache(options, results) ) { bool hasError = (results->errorMessage != nullptr); success = !hasError; } else { // slow path: this is first process to load cache success = mapSplitCacheSystemWide(options, results); } #endif } return success; } /* 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 TARGET_OS_IPHONE 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 TARGET_OS_IPHONE // 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 ( 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) ) return false; uint32_t imageIndex; return loadInfo.loadAddress->hasImagePath(dylibPathToFind, imageIndex); } void deallocateExistingSharedCache() { #if TARGET_OS_SIMULATOR // dyld deallocated macOS shared cache before jumping into dyld_sim #else // <rdar://problem/50773474> remove the shared region sub-map uint64_t existingCacheAddress = 0; if ( __shared_region_check_np(&existingCacheAddress) == 0 ) { // <rdar://problem/73957993> (void)__shared_region_check_np(NULL); } #endif } } // namespace dyld3 #endif // !TARGET_OS_EXCLAVEKIT |