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--- dyld/dyld-960/cache-builder/CacheBuilder.cpp
+++ dyld/dyld-1042.1/cache-builder/CacheBuilder.cpp
@@ -24,6 +24,7 @@
#include <assert.h>
+#include "ASLRTracker.h"
#include "MachOFileAbstraction.hpp"
#include "DyldSharedCache.h"
#include "CacheBuilder.h"
@@ -51,9 +52,9 @@
void CacheBuilder::copyRawSegments()
{
const bool log = false;
- const bool logCFConstants = false;
- forEachDylibInfo(^(const DylibInfo& dylib, Diagnostics& dylibDiag, ASLR_Tracker& dylibASLRTracker) {
+ forEachDylibInfo(^(const DylibInfo& dylib, Diagnostics& dylibDiag, cache_builder::ASLR_Tracker& dylibASLRTracker,
+ const CacheBuilder::DylibSectionCoalescer* sectionCoalescer) {
for (const SegmentMappingInfo& info : dylib.cacheLocation) {
if (log) fprintf(stderr, "copy %s segment %15s (0x%08X bytes) from %p to %p (logical addr 0x%llX) for %s\n",
_options.archs->name(), info.segName, info.copySegmentSize, info.srcSegment, info.dstSegment, info.dstCacheUnslidAddress, dylib.input->mappedFile.runtimePath.c_str());
@@ -62,54 +63,34 @@
});
// Copy the coalesced __TEXT sections
- const uint64_t numCoalescedSections = sizeof(CacheCoalescedText::SupportedSections) / sizeof(*CacheCoalescedText::SupportedSections);
- dispatch_apply(numCoalescedSections, DISPATCH_APPLY_AUTO, ^(size_t index) {
- const CacheCoalescedText::StringSection& cacheStringSection = _coalescedText.getSectionData(CacheCoalescedText::SupportedSections[index]);
- if (log) fprintf(stderr, "copy %s __TEXT_COAL section %s (0x%08X bytes) to %p (logical addr 0x%llX)\n",
- _options.archs->name(), CacheCoalescedText::SupportedSections[index],
- cacheStringSection.bufferSize, cacheStringSection.bufferAddr, cacheStringSection.bufferVMAddr);
- for (const auto& stringAndOffset : cacheStringSection.stringsToOffsets)
- ::memcpy(cacheStringSection.bufferAddr + stringAndOffset.second, stringAndOffset.first.data(), stringAndOffset.first.size() + 1);
- });
+ for ( const auto* coalescedSection : { &_objcCoalescedClassNames, &_objcCoalescedMethodNames, &_objcCoalescedMethodTypes } ) {
+ if ( coalescedSection->bufferSize == 0 )
+ continue;
- // Copy the coalesced CF sections
- if ( _coalescedText.cfStrings.bufferSize != 0 ) {
- uint8_t* dstBuffer = _coalescedText.cfStrings.bufferAddr;
- uint64_t dstBufferVMAddr = _coalescedText.cfStrings.bufferVMAddr;
- forEachDylibInfo(^(const DylibInfo& dylib, Diagnostics& dylibDiag, ASLR_Tracker& dylibASLRTracker) {
- const char* segmentName = "__OBJC_CONST";
- const char* sectionName = "__cfstring";
- const DylibTextCoalescer::DylibSectionOffsetToCacheSectionOffset& sectionData = dylib.textCoalescer.getSectionCoalescer(segmentName, sectionName);
- if ( sectionData.empty() )
- return;
-
- uint64_t sectionContentSize = 0;
- const void* sectionContent = dylib.input->mappedFile.mh->findSectionContent(segmentName, sectionName, sectionContentSize);
- assert(sectionContent != nullptr);
- assert(sectionContentSize != 0);
- for (const auto& dylibOffsetAndCacheOffset : sectionData) {
- uint64_t dylibOffset = dylibOffsetAndCacheOffset.first;
- uint64_t cacheOffset = dylibOffsetAndCacheOffset.second;
- if (logCFConstants) fprintf(stderr, "copy %s %s section %s (0x%08X bytes) to %p (logical addr 0x%llX)\n",
- _options.archs->name(), segmentName, sectionName,
- (uint32_t)DyldSharedCache::ConstantClasses::cfStringAtomSize, dstBuffer + cacheOffset, dstBufferVMAddr + cacheOffset);
- ::memcpy(dstBuffer + cacheOffset, (const uint8_t*)sectionContent + dylibOffset, (size_t)DyldSharedCache::ConstantClasses::cfStringAtomSize);
- }
- });
+ if (log) {
+ fprintf(stderr, "copy %s __TEXT_COAL section %s (0x%08X bytes) to %p (logical addr 0x%llX)\n",
+ _options.archs->name(), coalescedSection->sectionName.data(),
+ coalescedSection->bufferSize, coalescedSection->bufferAddr, coalescedSection->bufferVMAddr);
+ }
+ for (const auto& stringAndOffset : coalescedSection->stringsToOffsets) {
+ ::memcpy(coalescedSection->bufferAddr + stringAndOffset.second,
+ stringAndOffset.first.data(), stringAndOffset.first.size() + 1);
+ }
}
}
void CacheBuilder::adjustAllImagesForNewSegmentLocations(uint64_t cacheBaseAddress,
- LOH_Tracker* lohTracker,
- const CacheBuilder::CacheCoalescedText* coalescedText)
+ LOH_Tracker* lohTracker)
{
// Note this cannot to be done in parallel because the LOH Tracker and aslr tracker are not thread safe
__block bool badDylib = false;
- forEachDylibInfo(^(const DylibInfo& dylib, Diagnostics& dylibDiag, ASLR_Tracker& dylibASLRTracker) {
+ forEachDylibInfo(^(const DylibInfo& dylib, Diagnostics& dylibDiag,
+ cache_builder::ASLR_Tracker& dylibASLRTracker,
+ const CacheBuilder::DylibSectionCoalescer* sectionCoalescer) {
if ( dylibDiag.hasError() )
return;
adjustDylibSegments(dylib, dylibDiag, cacheBaseAddress, dylibASLRTracker,
- lohTracker, coalescedText);
+ lohTracker, sectionCoalescer);
if ( dylibDiag.hasError() )
badDylib = true;
});
@@ -119,695 +100,86 @@
}
}
+//////////////////////////// CacheBuilder::DylibSectionCoalescer ////////////////////////////////////
-CacheBuilder::ASLR_Tracker::~ASLR_Tracker()
+// Returns true if the section was removed from the source dylib after being optimized
+bool CacheBuilder::DylibSectionCoalescer::sectionWasRemoved(std::string_view segmentName,
+ std::string_view sectionName) const
{
- if ( _bitmap != nullptr )
- ::free(_bitmap);
-#if BUILDING_APP_CACHE_UTIL
- if ( _cacheLevels != nullptr )
- ::free(_cacheLevels);
-#endif
-}
+ if ( const OptimizedSection* section = this->getSection(segmentName, sectionName) ) {
+ // Some sections, eg, GOTs, are optimized but not removed
+ if ( !section->sectionWillBeRemoved )
+ return false;
-void CacheBuilder::ASLR_Tracker::setDataRegion(const void* rwRegionStart, size_t rwRegionSize)
-{
- _pageCount = (unsigned)(rwRegionSize+_pageSize-1)/_pageSize;
- _regionStart = (uint8_t*)rwRegionStart;
- _regionEnd = (uint8_t*)rwRegionStart + rwRegionSize;
- _bitmap = (bool*)calloc(_pageCount*(_pageSize/kMinimumFixupAlignment)*sizeof(bool), 1);
-#if BUILDING_APP_CACHE_UTIL
- size_t cacheLevelsSize = (_pageCount*(_pageSize/kMinimumFixupAlignment)*sizeof(uint8_t));
- _cacheLevels = (uint8_t*)malloc(cacheLevelsSize);
- memset(_cacheLevels, (int)~0U, cacheLevelsSize);
-#endif
-}
-
-void CacheBuilder::ASLR_Tracker::add(void* loc, uint8_t level)
-{
- if (!_enabled)
- return;
- uint8_t* p = (uint8_t*)loc;
- assert(p >= _regionStart);
- assert(p < _regionEnd);
- _bitmap[(p-_regionStart)/kMinimumFixupAlignment] = true;
-
-#if BUILDING_APP_CACHE_UTIL
- if ( level != (uint8_t)~0U ) {
- _cacheLevels[(p-_regionStart)/kMinimumFixupAlignment] = level;
- }
-#endif
-}
-
-void CacheBuilder::ASLR_Tracker::remove(void* loc)
-{
- if (!_enabled)
- return;
- uint8_t* p = (uint8_t*)loc;
- assert(p >= _regionStart);
- assert(p < _regionEnd);
- _bitmap[(p-_regionStart)/kMinimumFixupAlignment] = false;
-}
-
-bool CacheBuilder::ASLR_Tracker::has(void* loc, uint8_t* level) const
-{
- if (!_enabled)
- return true;
- uint8_t* p = (uint8_t*)loc;
- assert(p >= _regionStart);
- assert(p < _regionEnd);
-
- if ( _bitmap[(p-_regionStart)/kMinimumFixupAlignment] ) {
-#if BUILDING_APP_CACHE_UTIL
- if ( level != nullptr ) {
- uint8_t levelValue = _cacheLevels[(p-_regionStart)/kMinimumFixupAlignment];
- if ( levelValue != (uint8_t)~0U )
- *level = levelValue;
- }
-#endif
- return true;
- }
- return false;
-}
-
-void CacheBuilder::ASLR_Tracker::setHigh8(void* p, uint8_t high8)
-{
- _high8Map[p] = high8;
-}
-
-void CacheBuilder::ASLR_Tracker::setAuthData(void* p, uint16_t diversity, bool hasAddrDiv, uint8_t key)
-{
- _authDataMap[p] = {diversity, hasAddrDiv, key};
-}
-
-void CacheBuilder::ASLR_Tracker::setRebaseTarget32(void*p, uint32_t targetVMAddr)
-{
- _rebaseTarget32[p] = targetVMAddr;
-}
-
-void CacheBuilder::ASLR_Tracker::setRebaseTarget64(void*p, uint64_t targetVMAddr)
-{
- _rebaseTarget64[p] = targetVMAddr;
-}
-
-bool CacheBuilder::ASLR_Tracker::hasHigh8(void* p, uint8_t* highByte) const
-{
- auto pos = _high8Map.find(p);
- if ( pos == _high8Map.end() )
- return false;
- *highByte = pos->second;
- return true;
-}
-
-bool CacheBuilder::ASLR_Tracker::hasAuthData(void* p, uint16_t* diversity, bool* hasAddrDiv, uint8_t* key) const
-{
- auto pos = _authDataMap.find(p);
- if ( pos == _authDataMap.end() )
- return false;
- *diversity = pos->second.diversity;
- *hasAddrDiv = pos->second.addrDiv;
- *key = pos->second.key;
- return true;
-}
-
-bool CacheBuilder::ASLR_Tracker::hasRebaseTarget32(void* p, uint32_t* vmAddr) const
-{
- auto pos = _rebaseTarget32.find(p);
- if ( pos == _rebaseTarget32.end() )
- return false;
- *vmAddr = pos->second;
- return true;
-}
-
-bool CacheBuilder::ASLR_Tracker::hasRebaseTarget64(void* p, uint64_t* vmAddr) const
-{
- auto pos = _rebaseTarget64.find(p);
- if ( pos == _rebaseTarget64.end() )
- return false;
- *vmAddr = pos->second;
- return true;
-}
-
-std::vector<void*> CacheBuilder::ASLR_Tracker::getRebaseTargets() const {
- std::vector<void*> targets;
- for (const auto& target : _rebaseTarget32)
- targets.push_back(target.first);
- for (const auto& target : _rebaseTarget64)
- targets.push_back(target.first);
- return targets;
-}
-
-//////////////////////////// DylibTextCoalescer ////////////////////////////////////
-
-bool CacheBuilder::DylibTextCoalescer::segmentWasCoalesced(std::string_view segmentName) const {
- if (segmentName.size() > 16)
- segmentName = segmentName.substr(0, 16);
-
- if ( segmentName == "__OBJC_CONST" ) {
- return !cfStrings.empty();
+ return !section->offsetMap.empty();
}
return false;
}
-bool CacheBuilder::DylibTextCoalescer::sectionWasCoalesced(std::string_view segmentName,
- std::string_view sectionName) const {
+// Returns true if the section was totally removed, and hasn't been redirected to some coalesced or
+// optimized location
+bool CacheBuilder::DylibSectionCoalescer::sectionWasObliterated(std::string_view segmentName,
+ std::string_view sectionName) const
+{
+ if ( const OptimizedSection* section = this->getSection(segmentName, sectionName) ) {
+ return section->sectionIsObliterated;
+ }
+
+ return false;
+}
+
+// Returns true if the section was optimized. It may or may not have been removed too, see sectionWasRemoved().
+bool CacheBuilder::DylibSectionCoalescer::sectionWasOptimized(std::string_view segmentName,
+ std::string_view sectionName) const
+{
+ if ( const OptimizedSection* section = this->getSection(segmentName, sectionName) )
+ return !section->offsetMap.empty() || section->sectionIsObliterated;
+
+ return false;
+}
+
+CacheBuilder::DylibSectionCoalescer::OptimizedSection*
+CacheBuilder::DylibSectionCoalescer::getSection(std::string_view segmentName, std::string_view sectionName)
+{
if (segmentName.size() > 16)
segmentName = segmentName.substr(0, 16);
if (sectionName.size() > 16)
sectionName = sectionName.substr(0, 16);
if ( segmentName == "__TEXT" ) {
- std::map<std::string_view, const DylibSectionOffsetToCacheSectionOffset*> supportedSections = {
- { "__objc_classname", &objcClassNames },
- { "__objc_methname", &objcMethNames },
- { "__objc_methtype", &objcMethTypes }
- };
- auto it = supportedSections.find(sectionName);
- if (it == supportedSections.end())
- return false;
- return !it->second->empty();
+ if ( sectionName == "__objc_classname" )
+ return &this->objcClassNames;
+ if ( sectionName == "__objc_methname" )
+ return &this->objcMethNames;
+ if ( sectionName == "__objc_methtype" )
+ return &this->objcMethTypes;
+ } else if ( segmentName == "__TEXT_EXEC" ) {
+ if ( sectionName == "__auth_stubs" )
+ return &this->auth_stubs;
+ } else if ( segmentName == "__DATA_CONST" ) {
+ if ( sectionName == "__got" )
+ return &this->gots;
+ } else if ( segmentName == "__AUTH_CONST" ) {
+ if ( sectionName == "__auth_got" )
+ return &this->auth_gots;
}
- if ( segmentName == "__OBJC_CONST" ) {
- if ( sectionName == "__cfstring" ) {
- return !cfStrings.empty();
- }
- }
-
- return false;
+ return nullptr;
}
-CacheBuilder::DylibTextCoalescer::DylibSectionOffsetToCacheSectionOffset&
-CacheBuilder::DylibTextCoalescer::getSectionCoalescer(std::string_view segmentName, std::string_view sectionName) {
- if (segmentName.size() > 16)
- segmentName = segmentName.substr(0, 16);
- if (sectionName.size() > 16)
- sectionName = sectionName.substr(0, 16);
-
- if ( segmentName == "__TEXT" ) {
- std::map<std::string_view, DylibSectionOffsetToCacheSectionOffset*> supportedSections = {
- { "__objc_classname", &objcClassNames },
- { "__objc_methname", &objcMethNames },
- { "__objc_methtype", &objcMethTypes }
- };
- auto it = supportedSections.find(sectionName);
- assert(it != supportedSections.end());
- return *it->second;
- }
-
- if ( segmentName == "__OBJC_CONST" ) {
- if ( sectionName == "__cfstring" ) {
- return cfStrings;
- }
- }
-
- assert(false);
+const CacheBuilder::DylibSectionCoalescer::OptimizedSection*
+CacheBuilder::DylibSectionCoalescer::getSection(std::string_view segmentName, std::string_view sectionName) const
+{
+ return ((CacheBuilder::DylibSectionCoalescer*)this)->getSection(segmentName, sectionName);
}
-const CacheBuilder::DylibTextCoalescer::DylibSectionOffsetToCacheSectionOffset&
-CacheBuilder::DylibTextCoalescer::getSectionCoalescer(std::string_view segmentName, std::string_view sectionName) const {
- if (segmentName.size() > 16)
- segmentName = segmentName.substr(0, 16);
- if (sectionName.size() > 16)
- sectionName = sectionName.substr(0, 16);
-
- if ( segmentName == "__TEXT" ) {
- std::map<std::string_view, const DylibSectionOffsetToCacheSectionOffset*> supportedSections = {
- { "__objc_classname", &objcClassNames },
- { "__objc_methname", &objcMethNames },
- { "__objc_methtype", &objcMethTypes }
- };
- auto it = supportedSections.find(sectionName);
- assert(it != supportedSections.end());
- return *it->second;
- }
-
- if ( segmentName == "__OBJC_CONST" ) {
- if ( sectionName == "__cfstring" ) {
- return cfStrings;
- }
- }
-
- assert(false);
+void CacheBuilder::DylibSectionCoalescer::clear()
+{
+ objcClassNames.clear();
+ objcMethNames.clear();
+ objcMethTypes.clear();
+ auth_stubs.clear();
+ gots.clear();
+ auth_gots.clear();
}
-
-//////////////////////////// CacheCoalescedText ////////////////////////////////////
-const char* CacheBuilder::CacheCoalescedText::SupportedSections[] = {
- "__objc_classname",
- "__objc_methname",
- "__objc_methtype",
-};
-
-void CacheBuilder::CacheCoalescedText::
- parseCoalescableText(const dyld3::MachOAnalyzer* ma,
- DylibTextCoalescer& textCoalescer,
- const IMPCaches::SelectorMap& selectors,
- IMPCaches::HoleMap& selectorsHoleMap) {
- static const bool log = false;
-
- // We can only remove sections if we know we have split seg v2 to point to it
- // Otherwise, a PC relative load in the __TEXT segment wouldn't know how to point to the new strings
- // which are no longer in the same segment
- uint32_t splitSegSize = 0;
- const void* splitSegStart = ma->getSplitSeg(splitSegSize);
- if (!splitSegStart)
- return;
-
- if ((*(const uint8_t*)splitSegStart) != DYLD_CACHE_ADJ_V2_FORMAT)
- return;
-
- // We can only remove sections from the end of a segment, so cache them all and walk backwards.
- __block std::vector<std::pair<std::string, dyld3::MachOAnalyzer::SectionInfo>> textSectionInfos;
- ma->forEachSection(^(const dyld3::MachOAnalyzer::SectionInfo §Info, bool malformedSectionRange, bool &stop) {
- if (strcmp(sectInfo.segInfo.segName, "__TEXT") != 0)
- return;
- assert(!malformedSectionRange);
- textSectionInfos.push_back({ sectInfo.sectName, sectInfo });
- });
-
- const std::set<std::string_view> supportedSections(std::begin(SupportedSections), std::end(SupportedSections));
- int64_t slide = ma->getSlide();
-
- bool isSelectorsSection = false;
- for (auto sectionInfoIt = textSectionInfos.rbegin(); sectionInfoIt != textSectionInfos.rend(); ++sectionInfoIt) {
- const std::string& sectionName = sectionInfoIt->first;
- const dyld3::MachOAnalyzer::SectionInfo& sectInfo = sectionInfoIt->second;
-
- isSelectorsSection = (sectionName == "__objc_methname");
-
- // If we find a section we can't handle then stop here. Hopefully we coalesced some from the end.
- if (supportedSections.find(sectionName) == supportedSections.end())
- break;
-
- StringSection& cacheStringSection = getSectionData(sectionName);
-
- DylibTextCoalescer::DylibSectionOffsetToCacheSectionOffset& sectionStringData = textCoalescer.getSectionCoalescer("__TEXT", sectionName);
-
- // Walk the strings in this section
- const uint8_t* content = (uint8_t*)(sectInfo.sectAddr + slide);
- const char* s = (char*)content;
- const char* end = s + sectInfo.sectSize;
- while ( s < end ) {
- std::string_view str = s;
- int cacheSectionOffset = 0;
-
- auto it = cacheStringSection.stringsToOffsets.find(str);
- if (it != cacheStringSection.stringsToOffsets.end()) {
- // Debugging only. If we didn't include the string then we saved that many bytes
- cacheStringSection.savedSpace += str.size() + 1;
- cacheSectionOffset = it->second;
- } else if (isSelectorsSection) {
- // If we are in the selectors section, we need to move
- // the selectors in the selector map to their correct addresses,
- // and fill the holes with the rest
-
-#if BUILDING_APP_CACHE_UTIL
- cacheSectionOffset = cacheStringSection.bufferSize;
-#else
- const IMPCaches::SelectorMap::UnderlyingMap & map = selectors.map;
- IMPCaches::SelectorMap::UnderlyingMap::const_iterator selectorsIterator = map.find(str);
- if (selectorsIterator != map.end()) {
- cacheSectionOffset = selectorsIterator->second->offset;
- } else {
- cacheSectionOffset = selectorsHoleMap.addStringOfSize((unsigned)str.size() + 1);
- }
-#endif
- cacheStringSection.stringsToOffsets[str] = cacheSectionOffset;
- uint32_t sizeAtLeast = cacheSectionOffset + (uint32_t)str.size() + 1;
- if (cacheStringSection.bufferSize < sizeAtLeast) {
- cacheStringSection.bufferSize = sizeAtLeast;
- }
- } else {
- auto itAndInserted = cacheStringSection.stringsToOffsets.insert({ str, cacheStringSection.bufferSize });
- cacheSectionOffset = itAndInserted.first->second;
- assert(itAndInserted.second);
-
- cacheStringSection.bufferSize += str.size() + 1;
- if (log) {
- printf("Selector: %s -> %s\n", ma->installName(), s);
- }
- }
-
- // Now keep track of this offset in our source dylib as pointing to this offset
- uint32_t sourceSectionOffset = (uint32_t)((uint64_t)s - (uint64_t)content);
- sectionStringData[sourceSectionOffset] = cacheSectionOffset;
- s += str.size() + 1;
- }
- }
-}
-
-void CacheBuilder::CacheCoalescedText::parseCFConstants(const dyld3::MachOAnalyzer *ma,
- DylibTextCoalescer &textCoalescer) {
- static const bool log = false;
-
- // FIXME: Re-enable this once we can correctly patch the shared cache
- if ( ma != nullptr )
- return;
-
- if ( !ma->is64() )
- return;
-
- // We only support chained fixups as we need to rewrite binds/rebases after applying split seg
- // and that is much easier with chained fixups than opcodes
- if ( !ma->hasChainedFixupsLoadCommand() )
- return;
-
- const uint16_t pointerFormat = ma->chainedPointerFormat();
- if ( (pointerFormat != DYLD_CHAINED_PTR_ARM64E) && (pointerFormat != DYLD_CHAINED_PTR_ARM64E_USERLAND24) )
- return;
-
- // We can only remove sections if we know we have split seg v2 to point to it
- // Otherwise, a PC relative load in the __TEXT segment wouldn't know how to point to the new constants
- // which are no longer in the same segment
- if ( !ma->isSplitSegV2() )
- return;
-
- // We can only remove sections from the end of a segment, so cache them all and walk backwards.
- __block std::vector<std::pair<std::string, dyld3::MachOAnalyzer::SectionInfo>> dataSectionInfos;
- __block uint64_t cstringStartVMAddr = 0;
- __block uint64_t cstringEndVMAddr = 0;
- ma->forEachSection(^(const dyld3::MachOAnalyzer::SectionInfo §Info, bool malformedSectionRange, bool &stop) {
- if ( malformedSectionRange )
- return;
- if ( strcmp(sectInfo.segInfo.segName, "__OBJC_CONST") == 0 ) {
- dataSectionInfos.push_back({ sectInfo.sectName, sectInfo });
- return;
- }
- if ( strcmp(sectInfo.segInfo.segName, "__TEXT") == 0 ) {
- if ( strcmp(sectInfo.sectName, "__cstring") == 0 ) {
- if ( ( (sectInfo.sectFlags & SECTION_TYPE) == S_CSTRING_LITERALS ) ) {
- cstringStartVMAddr = sectInfo.sectAddr;
- cstringEndVMAddr = cstringStartVMAddr + sectInfo.sectSize;
- }
- }
- }
- });
-
- // We need to clear the chained pointer fixups for the whole segment, so can only
- // process any type of CF object if we can process them all
- if ( dataSectionInfos.size() != 1 )
- return;
-
- if ( dataSectionInfos.front().first != "__cfstring" )
- return;
-
- if ( cstringStartVMAddr == 0 )
- return;
-
- const dyld3::MachOAnalyzer::SectionInfo& cfStringsSection = dataSectionInfos.back().second;
-
- // A CFString is layed out in memory as
- // {
- // uintptr_t isa;
- // uint32_t encoding;
- // uint32_t padding;
- // uintptr_t cstringData;
- // uintptr_t cstringLength;
- // }
- const uint64_t cstringDataOffset = 16;
- const char* className = cfStrings.isaClassName;
- if ( cfStringsSection.sectSize % (uint32_t)DyldSharedCache::ConstantClasses::cfStringAtomSize ) {
- // We don't support padding or any kind on the section
- return;
- }
-
- uint64_t baseAddress = ma->preferredLoadAddress();
-
- uint64_t startVMOffset = cfStringsSection.sectAddr - baseAddress;
- uint64_t endVMOffset = startVMOffset + cfStringsSection.sectSize;
-
- __block Diagnostics diag;
-
- // Make sure no symbols are pointing in to this section
- __block bool hasSymbols = false;
- ma->forEachGlobalSymbol(diag, ^(const char *symbolName, uint64_t n_value, uint8_t n_type, uint8_t n_sect, uint16_t n_desc, bool &stop) {
- uint64_t vmOffset = n_value - baseAddress;
- if ( vmOffset < startVMOffset )
- return;
- if ( vmOffset >= endVMOffset )
- return;
- // In range of our section
- hasSymbols = true;
- stop = true;
- });
- if ( diag.hasError() )
- return;
- if ( hasSymbols )
- return;
-
- ma->forEachLocalSymbol(diag, ^(const char *symbolName, uint64_t n_value, uint8_t n_type, uint8_t n_sect, uint16_t n_desc, bool &stop) {
- uint64_t vmOffset = n_value - baseAddress;
- if ( vmOffset < startVMOffset )
- return;
- if ( vmOffset >= endVMOffset )
- return;
- // In range of our section
- hasSymbols = true;
- stop = true;
- });
- if ( diag.hasError() )
- return;
- if ( hasSymbols )
- return;
-
- ma->forEachExportedSymbol(diag, ^(const char *symbolName, uint64_t imageOffset, uint64_t flags, uint64_t other, const char *importName, bool &stop) {
- if ( imageOffset < startVMOffset )
- return;
- if ( imageOffset >= endVMOffset )
- return;
- // In range of our section
- hasSymbols = true;
- stop = true;
- });
- if ( diag.hasError() )
- return;
- if ( hasSymbols )
- return;
-
- __block std::vector<const char*> dependentPaths;
- ma->forEachDependentDylib(^(const char *loadPath, bool isWeak, bool isReExport,
- bool isUpward, uint32_t compatVersion, uint32_t curVersion, bool &stop) {
- dependentPaths.push_back(loadPath);
- });
-
- // Find all the binds to the ISA class. These delineate the atoms
- // In CoreFoundation itself, we are looking for rebases to the ISA
- __block std::vector<uint64_t> atomOffsets;
-
- bool dylibExportsISA = strcmp(ma->installName(), cfStrings.isaInstallName) == 0;
- if ( !dylibExportsISA ) {
- // This dylib doens't export the class, so look for binds to the ISA
- __block std::vector<std::pair<const char*, int>> bindTargetSymbols;
- ma->forEachChainedFixupTarget(diag, ^(int libraryOrdinal, const char* symbolName, uint64_t addend, bool weakImport, bool& stop) {
- bindTargetSymbols.push_back({ symbolName, libraryOrdinal });
- });
-
- __block bool foundBadBind = false;
- ma->withChainStarts(diag, ma->chainStartsOffset(), ^(const dyld_chained_starts_in_image* startsInfo) {
- if ( foundBadBind )
- return;
- ma->forEachFixupInAllChains(diag, startsInfo, false, ^(dyld3::MachOLoaded::ChainedFixupPointerOnDisk* fixupLoc,
- const dyld_chained_starts_in_segment* segInfo, bool& stopFixups) {
- // Skip anything not in this section
- uint64_t vmOffset = (uint8_t*)fixupLoc - (uint8_t*)ma;
- if ( vmOffset < startVMOffset )
- return;
- if ( vmOffset >= endVMOffset )
- return;
-
- uint32_t bindOrdinal;
- int64_t ptrAddend;
- if ( fixupLoc->isBind(pointerFormat, bindOrdinal, ptrAddend) ) {
- if ( ptrAddend != 0 ) {
- foundBadBind = true;
- stopFixups = true;
- return;
- }
- if ( bindOrdinal >= bindTargetSymbols.size() ) {
- foundBadBind = true;
- stopFixups = true;
- return;
- }
- if ( strcmp(bindTargetSymbols[bindOrdinal].first, className) != 0 ) {
- foundBadBind = true;
- stopFixups = true;
- return;
- }
- int libOrdinal = bindTargetSymbols[bindOrdinal].second;
- if ( libOrdinal <= 0 ) {
- foundBadBind = true;
- stopFixups = true;
- return;
- }
- int depIndex = libOrdinal - 1;
- if ( depIndex >= (int)dependentPaths.size() ) {
- foundBadBind = true;
- stopFixups = true;
- return;
- }
- const char* depLoadPath = dependentPaths[depIndex];
- // All dylibs must find the ISA in the same place
- if ( strcmp(cfStrings.isaInstallName, depLoadPath) != 0 ) {
- foundBadBind = true;
- stopFixups = true;
- return;
- }
- atomOffsets.push_back(vmOffset);
- }
- });
- });
- if ( foundBadBind )
- return;
-
- if ( atomOffsets.empty() )
- return;
- }
-
- if ( diag.hasError() )
- return;
-
- // Find all the rebases in the atoms, which correpond to pointers strings
- __block std::map<uint64_t, uint64_t> sectionRebases;
- ma->withChainStarts(diag, ma->chainStartsOffset(), ^(const dyld_chained_starts_in_image* startsInfo) {
- ma->forEachFixupInAllChains(diag, startsInfo, false, ^(dyld3::MachOLoaded::ChainedFixupPointerOnDisk* fixupLoc, const dyld_chained_starts_in_segment* segInfo, bool& stopFixups) {
- // Skip anything not in this section
- uint64_t vmOffset = (uint8_t*)fixupLoc - (uint8_t*)ma;
- if ( vmOffset < startVMOffset )
- return;
- if ( vmOffset >= endVMOffset )
- return;
-
- uint64_t rebaseTargetRuntimeOffset;
- if ( fixupLoc->isRebase(pointerFormat, 0, rebaseTargetRuntimeOffset) ) {
- if ( dylibExportsISA && (rebaseTargetRuntimeOffset == cfStrings.isaVMOffset) ) {
- atomOffsets.push_back(vmOffset);
- } else {
- sectionRebases[vmOffset] = rebaseTargetRuntimeOffset;
- }
- }
- });
- });
- if ( diag.hasError() )
- return;
-
- // Every atom should have a single rebase to a cstring
- if ( sectionRebases.size() != atomOffsets.size() )
- return;
-
- std::sort(atomOffsets.begin(), atomOffsets.end());
- for (uint64_t atomOffset : atomOffsets) {
- auto it = sectionRebases.find(atomOffset + cstringDataOffset);
- if ( it == sectionRebases.end() )
- return;
- }
-
- CFSection& stringSection = this->cfStrings;
- DylibTextCoalescer::DylibSectionOffsetToCacheSectionOffset& sectionData = textCoalescer.getSectionCoalescer("__OBJC_CONST", "__cfstring");
- for (uint64_t atomOffset : atomOffsets) {
- if ( log )
- printf("%s: found __cfstring at: 0x%llx\n", ma->installName(), atomOffset);
-
- // Now keep track of this offset in our source dylib as pointing to this offset
- uint32_t sourceSectionOffset = (uint32_t)(atomOffset - startVMOffset);
- uint32_t cacheSectionOffset = stringSection.bufferSize;
- sectionData[sourceSectionOffset] = cacheSectionOffset;
- stringSection.bufferSize += (uint32_t)DyldSharedCache::ConstantClasses::cfStringAtomSize;
- }
-}
-
-void CacheBuilder::CacheCoalescedText::clear() {
- *this = CacheBuilder::CacheCoalescedText();
-}
-
-
-CacheBuilder::CacheCoalescedText::StringSection& CacheBuilder::CacheCoalescedText::getSectionData(std::string_view sectionName) {
- if (sectionName.size() > 16)
- sectionName = sectionName.substr(0, 16);
- std::map<std::string_view, StringSection*> supportedSections = {
- { "__objc_classname", &objcClassNames },
- { "__objc_methname", &objcMethNames },
- { "__objc_methtype", &objcMethTypes }
- };
- auto it = supportedSections.find(sectionName);
- assert(it != supportedSections.end());
- return *it->second;
-}
-
-
-const CacheBuilder::CacheCoalescedText::StringSection& CacheBuilder::CacheCoalescedText::getSectionData(std::string_view sectionName) const {
- if (sectionName.size() > 16)
- sectionName = sectionName.substr(0, 16);
- std::map<std::string_view, const StringSection*> supportedSections = {
- { "__objc_classname", &objcClassNames },
- { "__objc_methname", &objcMethNames },
- { "__objc_methtype", &objcMethTypes }
- };
- auto it = supportedSections.find(sectionName);
- assert(it != supportedSections.end());
- return *it->second;
-}
-
-uint64_t CacheBuilder::CacheCoalescedText::getSectionVMAddr(std::string_view segmentName,
- std::string_view sectionName) const {
- if (segmentName.size() > 16)
- segmentName = segmentName.substr(0, 16);
- if (sectionName.size() > 16)
- sectionName = sectionName.substr(0, 16);
-
- if ( segmentName == "__TEXT" ) {
- return getSectionData(sectionName).bufferVMAddr;
- }
-
- if ( segmentName == "__OBJC_CONST" ) {
- if ( sectionName == "__cfstring" ) {
- return cfStrings.bufferVMAddr;
- }
- }
-
- assert(false);
-}
-
-uint8_t* CacheBuilder::CacheCoalescedText::getSectionBufferAddr(std::string_view segmentName,
- std::string_view sectionName) const {
- if (segmentName.size() > 16)
- segmentName = segmentName.substr(0, 16);
- if (sectionName.size() > 16)
- sectionName = sectionName.substr(0, 16);
-
- if ( segmentName == "__TEXT" ) {
- return getSectionData(sectionName).bufferAddr;
- }
-
- if ( segmentName == "__OBJC_CONST" ) {
- if ( sectionName == "__cfstring" ) {
- return cfStrings.bufferAddr;
- }
- }
-
- assert(false);
-}
-
-uint64_t CacheBuilder::CacheCoalescedText::getSectionObjcTag(std::string_view segmentName,
- std::string_view sectionName) const {
- if (segmentName.size() > 16)
- segmentName = segmentName.substr(0, 16);
- if (sectionName.size() > 16)
- sectionName = sectionName.substr(0, 16);
-
- if ( segmentName == "__TEXT" ) {
- // Nothing has a tag in __TEXT
- return 0;
- }
-
- if ( segmentName == "__OBJC_CONST" ) {
- if ( sectionName == "__cfstring" ) {
- // This is defined by objc as the tag we put in the high bits
- // FIXME: Get a tag from objc
- // return 1ULL << 63;
- return 0;
- }
- }
-
- assert(false);
-}