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--- dyld/dyld-1340/mach_o/Image.cpp
+++ /dev/null
@@ -1,1202 +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 <stdio.h>
-#include <string.h>
-#include <assert.h>
-#include <errno.h>
-#include <mach/machine.h>
-#include <mach-o/fat.h>
-#include <uuid/uuid.h>
-
-#include <TargetConditionals.h>
-#if !TARGET_OS_EXCLAVEKIT
- #include <mach-o/reloc.h>
- #include <libc_private.h>
-#endif // !TARGET_OS_EXCLAVEKIT
-
-#include "Image.h"
-#include "Misc.h"
-#include "CompactUnwind.h"
-#include "TargetPolicy.h"
-
-namespace mach_o {
-
-Image::Image(const void* buffer, size_t bufferSize, MappingKind kind)
- : _buffer((Header*)buffer), _bufferSize(bufferSize), _mappingKind(kind), _hasZerofillExpansion(false)
-{
- // figure out location of LINKEDIT
- switch ( kind ) {
- case MappingKind::wholeSliceMapped:
- _hasZerofillExpansion = false;
- break;
- case MappingKind::dyldLoadedPreFixups:
- case MappingKind::dyldLoadedPostFixups:
- // this is a loaded image with segments mapped at their respective VM addresses
- _hasZerofillExpansion = true;
- break;
- case MappingKind::unknown:
- _hasZerofillExpansion = inferIfZerofillExpanded();
- break;
- }
- _linkeditBias = _buffer->computeLinkEditBias(_hasZerofillExpansion);
-
- // minimal check of load commands
- if ( Error err = _buffer->validStructureLoadCommands(bufferSize) )
- return;
-
- // build parts
- makeExportsTrie();
- makeSymbolTable();
- makeRebaseOpcodes();
- makeBindOpcodes();
- makeLazyBindOpcodes();
- makeWeakBindOpcodes();
- makeChainedFixups();
- makeFunctionStarts();
- makeCompactUnwind();
- makeSplitSegInfo();
- makeFunctionVariants();
- makeFunctionVariantFixups();
-}
-
-// for dyld loaded images only
-Image::Image(const mach_header* mh)
-: _buffer((Header*)mh), _bufferSize(0), _mappingKind(MappingKind::dyldLoadedPostFixups)
-{
- // this is a loaded image with segments mapped at their respective VM addresses
- _hasZerofillExpansion = true;
- _linkeditBias = _buffer->computeLinkEditBias(_hasZerofillExpansion);
-
- // build parts
- makeExportsTrie();
- makeSymbolTable();
- makeRebaseOpcodes();
- makeBindOpcodes();
- makeLazyBindOpcodes();
- makeWeakBindOpcodes();
- makeChainedFixups();
- makeFunctionStarts();
- makeCompactUnwind();
- makeSplitSegInfo();
- makeFunctionVariants();
- makeFunctionVariantFixups();
-}
-
-
-// need move constructor because object has pointers to within itself (e.g. _exportsTrie points to _exportsTrieSpace)
-Image::Image(const Image&& other)
- : _buffer(other._buffer), _bufferSize(other._bufferSize), _linkeditBias(other._linkeditBias),
- _mappingKind(other._mappingKind), _hasZerofillExpansion(other._hasZerofillExpansion)
-{
- // build parts
- makeExportsTrie();
- makeSymbolTable();
- makeRebaseOpcodes();
- makeBindOpcodes();
- makeLazyBindOpcodes();
- makeWeakBindOpcodes();
- makeChainedFixups();
- makeFunctionStarts();
- makeCompactUnwind();
- makeSplitSegInfo();
- makeFunctionVariants();
- makeFunctionVariantFixups();
-}
-
-
-// used to figure out of mach-o was mapped with zero fill or not
-bool Image::inferIfZerofillExpanded() const
-{
- // MH_PRELOAD files can only be wholeSliceMapped because load commands and linkedit are not in segments
- if ( _buffer->isPreload() || _buffer->isFileSet() )
- return false;
-
- // if file has no zero-fill, then both ways to load are the same
- if ( !_buffer->hasZerofillExpansion() )
- return false;
-
- // if file is code-signed, check for code-sig-magic in both possible locations
- {
- uint32_t sigFileOffset;
- uint32_t sigSize;
- if ( _buffer->hasCodeSignature(sigFileOffset, sigSize) ) {
- if ( sigFileOffset < _bufferSize ) {
- const uint32_t* unexpandedLoc = (uint32_t*)((uint8_t*)_buffer + sigFileOffset);
- if ( *unexpandedLoc == 0xc00cdefa ) // CSMAGIC_EMBEDDED_SIGNATURE
- return false;
- const uint32_t* expandedLoc = (uint32_t*)((uint8_t*)_buffer + _buffer->zerofillExpansionAmount() + sigFileOffset);
- if ( *expandedLoc == 0xc00cdefa )
- return true;
- }
- }
- }
-
- // FIXME:
- assert(false && "handle unsigned");
-
- return false;
-}
-
-Error Image::validate() const
-{
- // validate mach_header and load commands
- if ( Error err = _buffer->valid(_bufferSize) )
- return err;
-
- // create Policy object for this binary
- Policy policy(_buffer->arch(), _buffer->platformAndVersions(), _buffer->mh.filetype, false);
-
- // validate initializers
- if ( gImageValidateInitializers ) {
- if ( Error err = this->validInitializers(policy) )
- return err;
- }
-
- // validate LINKEDIT
- if ( Error err = this->validLinkedit(policy) )
- return err;
-
- return Error::none();
-}
-
-Error Image::validLinkedit(const Policy& policy) const
-{
- // validate structure of linkedit
- if ( Error err = validStructureLinkedit(policy) )
- return err;
-
- uint64_t maxVmOffset = 0x4000;
- uint32_t segCount = this->segmentCount();
- MappedSegment segs[std::max(segCount,(uint32_t)1)];
- for (uint32_t i=0; i < segCount; ++i) {
- segs[i] = this->segment(i);
- if ( segs[i].segName != "__LINKEDIT" ) {
- maxVmOffset = std::max(maxVmOffset, segs[i].runtimeOffset + segs[i].runtimeSize);
- }
- }
- std::span<const MappedSegment> segSpan{segs, segCount};
-
- // if image has an exports trie, validate that
- if ( this->hasExportsTrie() ) {
- if ( Error err = this->exportsTrie().valid(header()->preferredLoadAddress(), maxVmOffset) )
- return err;
- }
-
- // if image has a symbol table, validate that
- if ( this->hasSymbolTable() ) {
- if ( Error err = this->symbolTable().valid(maxVmOffset) )
- return err;
- }
-
- // if image has rebase opcodes
- if ( this->hasRebaseOpcodes() ) {
- if ( Error err = this->rebaseOpcodes().valid(segSpan, _buffer->mayHaveTextFixups(), policy.enforceFixupsInWritableSegments()) )
- return err;
- }
-
- // if image has bind opcodes
- if ( this->hasBindOpcodes() ) {
- if ( Error err = this->bindOpcodes().valid(segSpan, _buffer->linkedDylibCount(), _buffer->mayHaveTextFixups(), policy.enforceFixupsInWritableSegments()) )
- return err;
- }
-
- // if image has lazy bind opcodes
- if ( this->hasLazyBindOpcodes() ) {
- if ( Error err = this->lazyBindOpcodes().valid(segSpan, _buffer->linkedDylibCount(), _buffer->mayHaveTextFixups(), policy.enforceFixupsInWritableSegments()) )
- return err;
- }
-
- // if image has chained fixups
- if ( this->hasChainedFixups() ) {
- if ( Error err = this->chainedFixups().valid(_buffer->preferredLoadAddress(), segSpan) )
- return err;
- }
-
- // if image has functions variant table
- if ( this->hasFunctionVariants() ) {
- if ( Error err = this->functionVariants().valid() )
- return err;
- }
-
- return Error::none();
-}
-
-namespace {
- struct LinkEditContentChunk
- {
- const char* name;
- uint32_t alignment;
- uint32_t fileOffset;
- size_t size;
-
- // only have a few chunks, so bubble sort is ok. Don't use libc's qsort because it may call malloc
- static void sort(LinkEditContentChunk array[], unsigned long count)
- {
- for ( unsigned i = 0; i < count - 1; ++i ) {
- bool done = true;
- for ( unsigned j = 0; j < count - i - 1; ++j ) {
- if ( array[j].fileOffset > array[j + 1].fileOffset ) {
- LinkEditContentChunk temp = array[j];
- array[j] = array[j + 1];
- array[j + 1] = temp;
- done = false;
- }
- }
- if ( done )
- break;
- }
- }
- };
-} // anonymous namespace
-
-#if !TARGET_OS_EXCLAVEKIT
-Error Image::validStructureLinkedit(const Policy& policy) const
-{
- // build vector of all blobs in LINKEDIT
- const uint32_t ptrSize = _buffer->pointerSize();
- LinkEditContentChunk blobs[32];
- __block LinkEditContentChunk* bp = blobs;
- __block uint32_t symCount = 0;
- __block uint32_t indSymCount = 0;
- __block bool hasIndSymTab = false;
- __block bool hasLocalRelocs = false;
- __block bool hasExternalRelocs = false;
- __block bool hasDyldInfo = false;
- __block bool hasChainedFixups = false;
- __block Error lcError;
- (void)_buffer->forEachLoadCommand(^(const load_command* cmd, bool& stop) {
- switch ( cmd->cmd ) {
- case LC_SYMTAB: {
- const symtab_command* symbTabCmd = (symtab_command*)cmd;
- symCount = symbTabCmd->nsyms;
- if ( symCount != 0 ) {
- if ( symCount > 0x10000000 ) {
- lcError = Error("malformed mach-o image: symbol table too large");
- stop = true;
- }
- size_t size = symCount * (ptrSize == 8 ? sizeof(nlist_64) : sizeof(struct nlist));
- *bp++ = { "symbol table", ptrSize, symbTabCmd->symoff, (uint32_t)size };
- }
- if ( symbTabCmd->strsize != 0 )
- *bp++ = { "symbol table strings", 1, symbTabCmd->stroff, symbTabCmd->strsize };
- } break;
- case LC_DYSYMTAB: {
- hasIndSymTab = true;
- const dysymtab_command* dySymTabCmd = (dysymtab_command*)cmd;
- if ( dySymTabCmd->nindirectsyms > 0x10000000 ) {
- lcError = Error("malformed mach-o image: indirect symbol table too large");
- stop = true;
- }
- else if ( dySymTabCmd->ilocalsym != 0 ) {
- lcError = Error("malformed mach-o image: indirect symbol table ilocalsym != 0");
- stop = true;
- }
- else if ( dySymTabCmd->iextdefsym != dySymTabCmd->nlocalsym ) {
- lcError = Error("malformed mach-o image: indirect symbol table iextdefsym != nlocalsym");
- stop = true;
- }
- else if ( dySymTabCmd->iundefsym != (dySymTabCmd->iextdefsym + dySymTabCmd->nextdefsym) ) {
- lcError = Error("malformed mach-o image: indirect symbol table iundefsym != iextdefsym+nextdefsym");
- stop = true;
- }
- indSymCount = dySymTabCmd->iundefsym + dySymTabCmd->nundefsym;
- if ( dySymTabCmd->nlocrel != 0 ) {
- hasLocalRelocs = true;
- *bp++ = { "local relocations", ptrSize, dySymTabCmd->locreloff, dySymTabCmd->nlocrel * sizeof(relocation_info) };
- }
- if ( dySymTabCmd->nextrel != 0 ) {
- hasExternalRelocs = true;
- *bp++ = { "external relocations", ptrSize, dySymTabCmd->extreloff, dySymTabCmd->nextrel * sizeof(relocation_info) };
- }
- if ( dySymTabCmd->nindirectsyms != 0 )
- *bp++ = { "indirect symbol table", 4, dySymTabCmd->indirectsymoff, dySymTabCmd->nindirectsyms * 4 };
- } break;
- case LC_DYLD_INFO_ONLY:
- hasDyldInfo = true;
- [[clang::fallthrough]];
- case LC_DYLD_INFO: {
- const dyld_info_command* dyldInfoCmd = (dyld_info_command*)cmd;
- if ( dyldInfoCmd->rebase_size != 0 )
- *bp++ = { "rebase opcodes", ptrSize, dyldInfoCmd->rebase_off, dyldInfoCmd->rebase_size };
- if ( dyldInfoCmd->bind_size != 0 )
- *bp++ = { "bind opcodes", ptrSize, dyldInfoCmd->bind_off, dyldInfoCmd->bind_size };
- if ( dyldInfoCmd->weak_bind_size != 0 )
- *bp++ = { "weak bind opcodes", ptrSize, dyldInfoCmd->weak_bind_off, dyldInfoCmd->weak_bind_size };
- if ( dyldInfoCmd->lazy_bind_size != 0 )
- *bp++ = { "lazy bind opcodes", ptrSize, dyldInfoCmd->lazy_bind_off, dyldInfoCmd->lazy_bind_size };
- if ( dyldInfoCmd->export_size != 0 )
- *bp++ = { "exports trie", ptrSize, dyldInfoCmd->export_off, dyldInfoCmd->export_size };
- } break;
- case LC_SEGMENT_SPLIT_INFO: {
- const linkedit_data_command* splitSegCmd = (linkedit_data_command*)cmd;
- if ( splitSegCmd->datasize != 0 )
- *bp++ = { "shared cache info", ptrSize, splitSegCmd->dataoff, splitSegCmd->datasize };
- } break;
- case LC_ATOM_INFO: {
- const linkedit_data_command* relinkCmd = (linkedit_data_command*)cmd;
- if ( relinkCmd->datasize != 0 )
- *bp++ = { "atom info", ptrSize, relinkCmd->dataoff, relinkCmd->datasize };
- } break;
- case LC_FUNCTION_STARTS: {
- const linkedit_data_command* funStartsCmd = (linkedit_data_command*)cmd;
- if ( funStartsCmd->datasize != 0 )
- *bp++ = { "function starts", ptrSize, funStartsCmd->dataoff, funStartsCmd->datasize };
- } break;
- case LC_DATA_IN_CODE: {
- const linkedit_data_command* dataInCodeCmd = (linkedit_data_command*)cmd;
- if ( dataInCodeCmd->datasize != 0 )
- *bp++ = { "data in code", ptrSize, dataInCodeCmd->dataoff, dataInCodeCmd->datasize };
- } break;
- case LC_CODE_SIGNATURE: {
- const linkedit_data_command* codeSigCmd = (linkedit_data_command*)cmd;
- if ( codeSigCmd->datasize != 0 )
- *bp++ = { "code signature", ptrSize, codeSigCmd->dataoff, codeSigCmd->datasize };
- } break;
- case LC_DYLD_EXPORTS_TRIE: {
- const linkedit_data_command* exportsTrieCmd = (linkedit_data_command*)cmd;
- if ( exportsTrieCmd->datasize != 0 )
- *bp++ = { "exports trie", ptrSize, exportsTrieCmd->dataoff, exportsTrieCmd->datasize };
- } break;
- case LC_DYLD_CHAINED_FIXUPS: {
- const linkedit_data_command* chainedFixupsCmd = (linkedit_data_command*)cmd;
- hasChainedFixups = true;
- if ( chainedFixupsCmd->datasize != 0 )
- *bp++ = { "chained fixups", ptrSize, chainedFixupsCmd->dataoff, chainedFixupsCmd->datasize };
- } break;
- }
- });
- if ( lcError )
- return std::move(lcError);
- if ( hasIndSymTab && (symCount != indSymCount))
- return Error("symbol count from symbol table and dynamic symbol table differ");
-
- // check for bad combinations
- if ( hasDyldInfo && policy.enforceOneFixupEncoding() ) {
- if ( hasLocalRelocs )
- return Error("malformed mach-o contains LC_DYLD_INFO_ONLY and local relocations");
- if ( hasExternalRelocs )
- return Error("malformed mach-o contains LC_DYLD_INFO_ONLY and external relocations");
- }
- if ( hasChainedFixups ) {
- if ( hasLocalRelocs )
- return Error("malformed mach-o contains LC_DYLD_CHAINED_FIXUPS and local relocations");
- if ( hasExternalRelocs )
- return Error("malformed mach-o contains LC_DYLD_CHAINED_FIXUPS and external relocations");
- }
- if ( hasDyldInfo && hasChainedFixups )
- return Error("malformed mach-o contains LC_DYLD_INFO and LC_DYLD_CHAINED_FIXUPS");
-
- // find range of LINKEDIT
- __block uint64_t linkeditFileOffsetStart = 0;
- __block uint64_t linkeditFileOffsetEnd = 0;
- if ( _buffer->isObjectFile() || _buffer->isPreload() ) {
- // .o and -preload files don't have LINKEDIT, but the LINKEDIT content is still at the end of the file after the last section content
- _buffer->forEachSection(^(const Header::SectionInfo& info, bool& stop) {
- uint8_t sectType = (info.flags & SECTION_TYPE);
- bool isZeroFill = ((sectType == S_ZEROFILL) || (sectType == S_THREAD_LOCAL_ZEROFILL));
- if ( isZeroFill )
- return;
- uint64_t sectionEnd = info.fileOffset + info.size;
- if ( sectionEnd > linkeditFileOffsetStart )
- linkeditFileOffsetStart = sectionEnd;
- });
- linkeditFileOffsetEnd = _bufferSize;
- if ( linkeditFileOffsetStart == 0 ) {
- // if all sections are zerofill sections, look for symbol table as start of linkedit
- _buffer->forEachLoadCommandSafe(^(const load_command* cmd, bool& stop) {
- if ( cmd->cmd == LC_SYMTAB ) {
- const symtab_command* symTab = (symtab_command*)cmd;
- linkeditFileOffsetStart = symTab->symoff;
- }
- });
- }
- }
- else {
- (void)_buffer->forEachLoadCommand(^(const load_command* cmd, bool& stop) {
- if ( cmd->cmd == LC_SEGMENT_64 ) {
- const segment_command_64* segCmd = (segment_command_64*)cmd;
- if ( strcmp(segCmd->segname, "__LINKEDIT") == 0 ) {
- linkeditFileOffsetStart = segCmd->fileoff;
- linkeditFileOffsetEnd = segCmd->fileoff + segCmd->filesize;
- stop = true;
- }
- }
- else if ( cmd->cmd == LC_SEGMENT ) {
- const segment_command* segCmd = (segment_command*)cmd;
- if ( strcmp(segCmd->segname, "__LINKEDIT") == 0 ) {
- linkeditFileOffsetStart = segCmd->fileoff;
- linkeditFileOffsetEnd = segCmd->fileoff + segCmd->filesize;
- stop = true;
- }
- }
- });
- if ( (linkeditFileOffsetStart == 0) || (linkeditFileOffsetEnd == 0) )
- return Error("bad or unknown fileoffset/size for LINKEDIT");
- }
-
- // sort blobs by file-offset and check for overlaps
- const unsigned long blobCount = bp - blobs;
- if ( blobCount == 0 ) {
- // ok for .o files or MH_FILESET to have no content and no symbols
- if ( _buffer->isObjectFile() || _buffer->isFileSet() )
- return Error::none();
- return Error("malformed mach-o has no LINKEDIT information");
- }
- LinkEditContentChunk::sort(blobs, blobCount);
- uint64_t prevEnd = linkeditFileOffsetStart;
- const char* prevName = "start of LINKEDIT";
- for ( unsigned long i = 0; i < blobCount; ++i ) {
- const LinkEditContentChunk& blob = blobs[i];
- if ( blob.fileOffset < prevEnd ) {
- return Error("LINKEDIT overlap of %s and %s", prevName, blob.name);
- }
- if ( greaterThanAddOrOverflow((uint64_t)blob.fileOffset, blob.size, linkeditFileOffsetEnd) ) {
- return Error("LINKEDIT content '%s' extends beyond end of segment", blob.name);
- }
- if ( (blob.fileOffset & (blob.alignment - 1)) != 0 ) {
- // <rdar://problem/51115705> relax code sig alignment for pre iOS 13
- if ( strcmp(blob.name, "code signature") == 0 ) {
- if ( policy.enforceCodeSignatureAligned() )
- return Error("mis-aligned code signature");
- }
- else {
- if ( policy.enforceLinkeditContentAlignment() )
- return Error("mis-aligned LINKEDIT content '%s'", blob.name);
- }
- }
- prevEnd = blob.fileOffset + blob.size;
- prevName = blob.name;
- }
-
- return Error::none();
-}
-
-struct VIS_HIDDEN SegmentRanges
-{
- struct SegmentRange {
- uint64_t vmAddrStart;
- uint64_t vmAddrEnd;
- uint32_t fileSize;
- };
-
- bool contains(uint64_t vmAddr) const {
- for (const SegmentRange& range : segments) {
- if ( (range.vmAddrStart <= vmAddr) && (vmAddr < range.vmAddrEnd) )
- return true;
- }
- return false;
- }
-
-private:
- SegmentRange localAlloc[8];
-
-public:
- dyld3::Array<SegmentRange> segments { localAlloc, sizeof(localAlloc) / sizeof(localAlloc[0]) };
-};
-
-
-Error Image::validInitializers(const Policy& policy) const
-{
- // rdar://127245061 (ld-prime initializer verification fails on Go object files)
- // Go creates object files with segment protections set to 0, while normally
- // they're set to all. Object files consist of a single segment though, so
- // we can skip the checks entirely.
- if ( header()->isObjectFile() )
- return Error::none();
-
- uint64_t prefLoadAddress = header()->preferredLoadAddress();
- uint64_t slide = header()->getSlide();
- __block Error anErr;
-
- __block SegmentRanges executableSegments;
- header()->forEachSegment(^(const Header::SegmentInfo& info, bool& stop) {
- if ( (info.initProt & VM_PROT_EXECUTE) != 0 ) {
- executableSegments.segments.push_back({ info.vmaddr, info.vmaddr + info.vmsize, (uint32_t)info.fileSize });
- }
- });
- if (executableSegments.segments.empty()) {
- return Error("no executable segments");
- }
-
- // validate LC_ROUTINES initializer
- header()->forEachLoadCommandSafe(^(const load_command* cmd, bool& stop) {
- if ( cmd->cmd == LC_ROUTINES ) {
- const routines_command* routines = (routines_command*)cmd;
- uint64_t dashInitAddr = routines->init_address;
- if ( !executableSegments.contains(dashInitAddr) ) {
- anErr = Error("LC_ROUTINES initializer 0x%08llX is not an offset to an executable segment", dashInitAddr);
- stop = true;
- }
- }
- else if ( cmd->cmd == LC_ROUTINES_64 ) {
- const routines_command_64* routines = (routines_command_64*)cmd;
- uint64_t dashInitAddr = routines->init_address;
- if ( !executableSegments.contains(dashInitAddr) ) {
- anErr = Error("LC_ROUTINES _64 initializer 0x%08llX is not an offset to an executable segment", dashInitAddr);
- stop = true;
- }
- }
- });
-
- // validate any function pointers in __DATA,__mod_init_func section
- header()->forEachSection(^(const Header::SectionInfo& sectInfo, bool& stop) {
- uint8_t sectType = (sectInfo.flags & SECTION_TYPE);
- if ( (sectType == S_MOD_INIT_FUNC_POINTERS) || (sectType == S_MOD_TERM_FUNC_POINTERS) ) {
- if ( (sectInfo.size % header()->pointerSize()) != 0 ) {
- anErr = Error("section %.*s/%.*s size (%llu) is not a multiple of pointer-size",
- (int)sectInfo.segmentName.size(), sectInfo.segmentName.data(),
- (int)sectInfo.sectionName.size(), sectInfo.sectionName.data(),
- sectInfo.size);
- stop = true;
- return;
- }
- if ( (sectInfo.address % header()->pointerSize()) != 0 ) {
- anErr = Error("section %.*s/%.*s address (0x%llX) is not pointer aligned",
- (int)sectInfo.segmentName.size(), sectInfo.segmentName.data(),
- (int)sectInfo.sectionName.size(), sectInfo.sectionName.data(),
- sectInfo.address);
- stop = true;
- return;
- }
- const uint8_t* sectionContent = (uint8_t*)header() + sectInfo.fileOffset;
- if ( header()->inDyldCache() )
- sectionContent = (uint8_t*)(sectInfo.address + header()->getSlide());
-
- if ( gImageAssumeContentRebased ) {
- // in dyld, when this is called, the image is already rebased, so we can use pointers in section
- const uintptr_t* initsStart = (uintptr_t*)sectionContent;
- const uintptr_t* initsEnd = (uintptr_t*)((uint8_t*)sectionContent + sectInfo.size);
- for (const uintptr_t* p=initsStart; p < initsEnd; ++p) {
- if ( !executableSegments.contains(*p) ) {
- anErr = Error("initializer 0x%08lX is not in an executable segment", *p);
- break;
- }
- }
- } else {
- if ( header()->is64() ) {
- const uint64_t* initsStart = (uint64_t*)sectionContent;
- const uint64_t* initsEnd = (uint64_t*)((uint8_t*)sectionContent + sectInfo.size);
- for (const uint64_t* p=initsStart; p < initsEnd; ++p) {
- uint64_t anInit = *p;
- anInit -= prefLoadAddress;
- // FIXME: as a quick hack, the low 32-bits with either rebase opcodes or chained fixups is offset in image
- uint32_t low32 = (uint32_t)anInit;
- if ( !executableSegments.contains(prefLoadAddress+low32) ) {
- anErr = Error("initializer %lu/%llu is not in an executable segment", p-initsStart, sectInfo.size/8);
- break;
- }
- }
- }
- else {
- const uint32_t* initsStart = (uint32_t*)sectionContent;
- const uint32_t* initsEnd = (uint32_t*)((uint8_t*)sectionContent + sectInfo.size);
- for (const uint32_t* p=initsStart; p < initsEnd; ++p) {
- uint32_t anInit = *p;
- anInit -= (uint32_t)prefLoadAddress;
- // FIXME: as a quick hack, the low 26-bits with either rebase opcodes or chained fixups is offset in image
- uint32_t low26 = anInit & 0x03FFFFFF;
- if ( !executableSegments.contains(prefLoadAddress+low26) ) {
- anErr = Error("initializer %lu/%llu is not in an executable segment", p-initsStart, sectInfo.size/84);
- break;
- }
- }
- }
- }
- if ( sectType == S_MOD_TERM_FUNC_POINTERS ) {
- if ( header()->isDyldManaged() && header()->isArch("arm6e") )
- anErr = Error("terminators section %.*s/%.*s not supported for arm64e",
- (int)sectInfo.segmentName.size(), sectInfo.segmentName.data(),
- (int)sectInfo.sectionName.size(), sectInfo.sectionName.data());
- }
- }
- });
- if ( anErr.hasError() )
- return std::move(anErr);
-
- // validate offsets in __TEXT,__init_offsets
- header()->forEachSection(^(const Header::SectionInfo& sectInfo, bool& stop) {
- if ( (sectInfo.flags & SECTION_TYPE) == S_INIT_FUNC_OFFSETS ) {
- const uint8_t* content = (uint8_t*)(sectInfo.address + slide);
- if ( sectInfo.segInitProt & VM_PROT_WRITE ) {
- anErr = Error("initializer offsets section %.*s/%.*s must be in read-only segment",
- (int)sectInfo.segmentName.size(), sectInfo.segmentName.data(),
- (int)sectInfo.sectionName.size(), sectInfo.sectionName.data());
- stop = true;
- return;
- }
- if ( (sectInfo.size % 4) != 0 ) {
- anErr = Error("initializer offsets section %.*s/%.*s has bad size",
- (int)sectInfo.segmentName.size(), sectInfo.segmentName.data(),
- (int)sectInfo.sectionName.size(), sectInfo.sectionName.data());
- stop = true;
- return;
- }
- if ( (sectInfo.address % 4) != 0 ) {
- anErr = Error("initializer offsets section %.*s/%.*s is not 4-byte aligned",
- (int)sectInfo.segmentName.size(), sectInfo.segmentName.data(),
- (int)sectInfo.sectionName.size(), sectInfo.sectionName.data());
- stop = true;
- return;
- }
- const uint32_t* initsStart = (uint32_t*)content;
- const uint32_t* initsEnd = (uint32_t*)((uint8_t*)content + sectInfo.size);
- for (const uint32_t* p=initsStart; p < initsEnd; ++p) {
- uint32_t anInitOffset = *p;
- if ( !executableSegments.contains(prefLoadAddress + anInitOffset) ) {
- anErr = Error("initializer 0x%08X is not an offset to an executable segment", anInitOffset);
- stop = true;
- break;
- }
- }
- }
- });
- if ( anErr.hasError() )
- return std::move(anErr);
-
- return Error::none();
-}
-#endif // !TARGET_OS_EXCLAVEKIT
-
-void Image::makeExportsTrie()
-{
- // if image has an exports trie, use placement new to build ExportTrie object in _exportsTrieSpace
- (void)_buffer->forEachLoadCommand(^(const load_command* cmd, bool& stop) {
- if ( cmd->cmd == LC_DYLD_EXPORTS_TRIE ) {
- const linkedit_data_command* exportsTrie = (linkedit_data_command*)cmd;
- if ( exportsTrie->dataoff != 0 )
- _exportsTrie = new (_exportsTrieSpace) ExportsTrie(_linkeditBias + exportsTrie->dataoff, exportsTrie->datasize);
- }
- else if ( (cmd->cmd == LC_DYLD_INFO) || (cmd->cmd == LC_DYLD_INFO_ONLY) ) {
- const dyld_info_command* dyldInfo = (dyld_info_command*)cmd;
- if ( dyldInfo->export_off != 0 )
- _exportsTrie = new (_exportsTrieSpace) ExportsTrie(_linkeditBias + dyldInfo->export_off, dyldInfo->export_size);
- }
- });
-}
-
-void Image::makeSymbolTable()
-{
- // if image has an nlist symbol table, use placement new to build SymbolTable object in _symbolTableSpace
- __block const symtab_command* symTabCmd = nullptr;
- __block const dysymtab_command* dynSymTabCmd = nullptr;
- (void)_buffer->forEachLoadCommand(^(const load_command* cmd, bool& stop) {
- if ( cmd->cmd == LC_SYMTAB ) {
- symTabCmd = (symtab_command*)cmd;
- }
- else if ( cmd->cmd == LC_DYSYMTAB ) {
- dynSymTabCmd = (dysymtab_command*)cmd;
- }
- });
-
- if ( symTabCmd == nullptr )
- return;
-
- uint32_t nlocalsym = 0;
- uint32_t nextdefsym = 0;
- uint32_t nundefsym = 0;
- if ( dynSymTabCmd != nullptr ) {
- // some .o files do not have LC_DYSYMTAB
- nlocalsym = dynSymTabCmd->nlocalsym;
- nextdefsym = dynSymTabCmd->nextdefsym;
- nundefsym = dynSymTabCmd->nundefsym;
- }
- if ( _buffer->is64() ) {
- uint64_t preferredLoadAddress = _buffer->preferredLoadAddress();
- const struct nlist_64* nlistArray = (struct nlist_64*)(_linkeditBias + symTabCmd->symoff);
- _symbolTable = new (_symbolTableSpace) NListSymbolTable(preferredLoadAddress, nlistArray, symTabCmd->nsyms, (char*)_linkeditBias + symTabCmd->stroff,
- symTabCmd->strsize, nlocalsym, nextdefsym, nundefsym);
- }
- else {
- uint32_t preferredLoadAddress = (uint32_t)_buffer->preferredLoadAddress();
- const struct nlist* nlistArray = (struct nlist*)(_linkeditBias + symTabCmd->symoff);
- _symbolTable = new (_symbolTableSpace) NListSymbolTable(preferredLoadAddress, nlistArray, symTabCmd->nsyms, (char*)_linkeditBias + symTabCmd->stroff,
- symTabCmd->strsize, nlocalsym, nextdefsym, nundefsym);
- }
-}
-
-void Image::makeRebaseOpcodes()
-{
- // if image has an rebase opcpdes, use placement new to build RebaseOpcodes object in _rebaseOpcodesSpace
- (void)_buffer->forEachLoadCommand(^(const load_command* cmd, bool& stop) {
- if ( (cmd->cmd == LC_DYLD_INFO) || (cmd->cmd == LC_DYLD_INFO_ONLY) ) {
- const dyld_info_command* dyldInfoCmd = (dyld_info_command*)cmd;
- if ( dyldInfoCmd->rebase_size != 0 )
- _rebaseOpcodes = new (_rebaseOpcodesSpace) RebaseOpcodes(_linkeditBias + dyldInfoCmd->rebase_off, dyldInfoCmd->rebase_size, _buffer->is64());
- }
- });
-}
-
-void Image::makeBindOpcodes()
-{
- // if image has an rebase opcpdes, use placement new to build BindOpcodes object in _bindOpcodesSpace
- (void)_buffer->forEachLoadCommand(^(const load_command* cmd, bool& stop) {
- if ( (cmd->cmd == LC_DYLD_INFO) || (cmd->cmd == LC_DYLD_INFO_ONLY) ) {
- const dyld_info_command* dyldInfoCmd = (dyld_info_command*)cmd;
- if ( dyldInfoCmd->bind_size != 0 )
- _bindOpcodes = new (_bindOpcodesSpace) BindOpcodes(_linkeditBias + dyldInfoCmd->bind_off, dyldInfoCmd->bind_size, _buffer->is64());
- }
- });
-}
-
-void Image::makeLazyBindOpcodes()
-{
- // if image has an rebase opcpdes, use placement new to build LazyBindOpcodes object in _lazyBindOpcodesSpace
- (void)_buffer->forEachLoadCommand(^(const load_command* cmd, bool& stop) {
- if ( (cmd->cmd == LC_DYLD_INFO) || (cmd->cmd == LC_DYLD_INFO_ONLY) ) {
- const dyld_info_command* dyldInfoCmd = (dyld_info_command*)cmd;
- if ( dyldInfoCmd->lazy_bind_size != 0 )
- _lazyBindOpcodes = new (_lazyBindOpcodesSpace) LazyBindOpcodes(_linkeditBias + dyldInfoCmd->lazy_bind_off, dyldInfoCmd->lazy_bind_size, _buffer->is64());
- }
- });
-}
-
-void Image::makeWeakBindOpcodes()
-{
- // if image has an rebase opcpdes, use placement new to build BindOpcodes object in _weakBindOpcodesSpace
- (void)_buffer->forEachLoadCommand(^(const load_command* cmd, bool& stop) {
- if ( (cmd->cmd == LC_DYLD_INFO) || (cmd->cmd == LC_DYLD_INFO_ONLY) ) {
- const dyld_info_command* dyldInfoCmd = (dyld_info_command*)cmd;
- if ( dyldInfoCmd->weak_bind_size != 0 )
- _weakBindOpcodes = new (_weakBindOpcodesSpace) BindOpcodes(_linkeditBias + dyldInfoCmd->weak_bind_off, dyldInfoCmd->weak_bind_size, _buffer->is64());
- }
- });
-}
-
-void Image::makeChainedFixups()
-{
- // if image has an fixup chains, use placement new to build ChainedFixups object in _chainedFixupsSpace
- (void)_buffer->forEachLoadCommand(^(const load_command* cmd, bool& stop) {
- if ( cmd->cmd == LC_DYLD_CHAINED_FIXUPS ) {
- const linkedit_data_command* chainedFixupsCmd = (linkedit_data_command*)cmd;
- if ( chainedFixupsCmd->datasize != 0 ) {
- const dyld_chained_fixups_header* fixupsHeader = (dyld_chained_fixups_header*)(_linkeditBias + chainedFixupsCmd->dataoff);
- _chainedFixups = new (_chainedFixupsSpace) ChainedFixups(fixupsHeader, chainedFixupsCmd->datasize);
- stop = true;
- }
- }
- });
-
- if ( !header()->isPreload() && !header()->isStaticExecutable() )
- return;
-
- if ( _chainedFixups == nullptr ) {
- header()->forEachSection(^(const Header::SectionInfo& info, bool& stop) {
- if ( (info.sectionName == "__chain_fixups") && (info.segmentName == "__TEXT") ) {
- const dyld_chained_fixups_header* fixupsHeader = (dyld_chained_fixups_header*)((uint8_t*)header() + info.fileOffset);
- _chainedFixups = new (_chainedFixupsSpace) ChainedFixups(fixupsHeader, (size_t)info.size);
- }
- });
- }
-}
-
-void Image::makeFunctionStarts()
-{
- // if image has an function starts, use placement new to build FunctionStarts object in _functionStartsSpace
- (void)_buffer->forEachLoadCommand(^(const load_command* cmd, bool& stop) {
- if ( cmd->cmd == LC_FUNCTION_STARTS ) {
- const linkedit_data_command* funcStartsCmd = (linkedit_data_command*)cmd;
- if ( funcStartsCmd->datasize != 0 ) {
- const uint8_t* functionsStartBytes = (uint8_t*)(_linkeditBias + funcStartsCmd->dataoff);
- _functionStarts = new (_functionStartsSpace) FunctionStarts(functionsStartBytes, funcStartsCmd->datasize);
- }
- }
- });
-}
-
-void Image::makeCompactUnwind()
-{
- // if image has an a compact unwind section, use placement new to build CompactUnwind object in _compactUnwindSpace
- _buffer->forEachSection(^(const Header::SectionInfo& info, bool& stop) {
- if ( (info.sectionName == "__unwind_info") && info.segmentName.starts_with("__TEXT") ) {
- const uint8_t* sectionContent = (uint8_t*)_buffer + info.fileOffset;
- _compactUnwind = new (_compactUnwindSpace) CompactUnwind(_buffer->arch(), sectionContent, (size_t)info.size);
- stop = true;
- }
- });
-}
-
-void Image::makeSplitSegInfo()
-{
- // if image has a split seg info load command, use placement new to build SplitSegInfo object in _splitSegInfoSpace
- (void)_buffer->forEachLoadCommand(^(const load_command* cmd, bool& stop) {
- if ( cmd->cmd == LC_SEGMENT_SPLIT_INFO ) {
- const linkedit_data_command* splitSegCmd = (linkedit_data_command*)cmd;
- const uint8_t* startBytes = (uint8_t*)(_linkeditBias + splitSegCmd->dataoff);
- _splitSegInfo = new (_splitSegSpace) SplitSegInfo(startBytes, splitSegCmd->datasize);
- stop = true;
- }
- });
-}
-
-void Image::makeFunctionVariants()
-{
- // if image has a LC_FUNCTION_VARIANTS load command, use placement new to build FunctionVariants object in _functionVariantsSpace
- (void)_buffer->forEachLoadCommand(^(const load_command* cmd, bool& stop) {
- if ( cmd->cmd == LC_FUNCTION_VARIANTS ) {
- const linkedit_data_command* functionVariantsCmd = (linkedit_data_command*)cmd;
- const uint8_t* startBytes = (uint8_t*)(_linkeditBias + functionVariantsCmd->dataoff);
- _functionVariants = new (_functionVariantsSpace) FunctionVariants(std::span<const uint8_t>(startBytes, functionVariantsCmd->datasize));
- stop = true;
- }
- });
-}
-
-void Image::makeFunctionVariantFixups()
-{
- // if image has a LC_FUNCTION_VARIANT_FIXUPS load command, use placement new to build _functionVariantFixups object in _functionVariantFixupsSpace
- (void)_buffer->forEachLoadCommand(^(const load_command* cmd, bool& stop) {
- if ( cmd->cmd == LC_FUNCTION_VARIANT_FIXUPS ) {
- const linkedit_data_command* functionVariantFixupsCmd = (linkedit_data_command*)cmd;
- const uint8_t* startBytes = (uint8_t*)(_linkeditBias + functionVariantFixupsCmd->dataoff);
- _functionVariantFixups = new (_functionVariantFixupsSpace) FunctionVariantFixups(std::span<const uint8_t>(startBytes, functionVariantFixupsCmd->datasize));
- stop = true;
- }
- });
-}
-
-uint32_t Image::segmentCount() const
-{
- __block uint32_t count = 0;
- (void)_buffer->forEachLoadCommand(^(const load_command* cmd, bool& stop) {
- if ( (cmd->cmd == LC_SEGMENT) || (cmd->cmd == LC_SEGMENT_64) )
- ++count;
- });
- return count;
-}
-
-MappedSegment Image::segment(uint32_t segIndex) const
-{
- __block MappedSegment result;
- __block uint32_t curSegIndex = 0;
- __block uint64_t textVmAddr = 0;
- (void)_buffer->forEachLoadCommand(^(const load_command* cmd, bool& stop) {
- if ( cmd->cmd == LC_SEGMENT_64 ) {
- const segment_command_64* segCmd = (segment_command_64*)cmd;
- if ( strcmp(segCmd->segname, "__TEXT") == 0 )
- textVmAddr = segCmd->vmaddr;
- if ( curSegIndex == segIndex ) {
- result.runtimeOffset = segCmd->vmaddr - textVmAddr;
- if ( _hasZerofillExpansion )
- result.content = (uint8_t*)_buffer + (segCmd->vmaddr - textVmAddr);
- else
- result.content = (uint8_t*)_buffer + segCmd->fileoff;
- result.runtimeSize = segCmd->vmsize;
- result.fileOffset = segCmd->fileoff;
- result.segName = segCmd->segname;
- result.readable = ((segCmd->initprot & VM_PROT_READ) != 0);
- result.writable = ((segCmd->initprot & VM_PROT_WRITE) != 0);
- result.executable = ((segCmd->initprot & VM_PROT_EXECUTE) != 0);
- stop = true;
- }
- ++curSegIndex;
- }
- else if ( cmd->cmd == LC_SEGMENT ) {
- const segment_command* segCmd = (segment_command*)cmd;
- if ( strcmp(segCmd->segname, "__TEXT") == 0 )
- textVmAddr = segCmd->vmaddr;
- if ( curSegIndex == segIndex ) {
- result.runtimeOffset = segCmd->vmaddr - textVmAddr;
- if ( _hasZerofillExpansion )
- result.content = (uint8_t*)_buffer + (segCmd->vmaddr - textVmAddr);
- else
- result.content = (uint8_t*)_buffer + segCmd->fileoff;
- result.runtimeSize = segCmd->vmsize;
- result.fileOffset = segCmd->fileoff;
- result.segName = segCmd->segname;
- result.readable = ((segCmd->initprot & VM_PROT_READ) != 0);
- result.writable = ((segCmd->initprot & VM_PROT_WRITE) != 0);
- result.executable = ((segCmd->initprot & VM_PROT_EXECUTE) != 0);
- stop = true;
- }
- ++curSegIndex;
- }
- });
- return result;
-}
-
-void Image::withSegments(void (^callback)(std::span<const MappedSegment> segments)) const
-{
- const uint32_t count = segmentCount();
- MappedSegment segments[count];
- for (uint32_t segIndex=0; segIndex < count; ++segIndex)
- segments[segIndex] = this->segment(segIndex);
-
- callback(std::span(segments, count));
-}
-
-// This is a high level abstraction for mach-o files. No matter the format, it returns all bind targets
-void Image::forEachBindTarget(void (^callback)(const Fixup::BindTarget& targetInfo, bool& stop)) const
-{
- if ( this->hasChainedFixups() ) {
- this->chainedFixups().forEachBindTarget(callback);
- }
- else if ( this->hasBindOpcodes() ) {
- // FIXME: Do we want to pass up the strong binds?
- this->bindOpcodes().forEachBindTarget(callback, ^(const char* symbolName) { });
-
- if ( hasLazyBindOpcodes() )
- this->lazyBindOpcodes().forEachBindTarget(callback, ^(const char* symbolName) { });
- }
-}
-
-void Image::forEachFixup(void (^callback)(const Fixup& fixup, bool& stop)) const
-{
- withSegments(^(std::span<const MappedSegment> segments) {
- forEachFixup(segments, callback);
- });
-}
-
-// This is a high level abstraction for mach-o files. No matter the format, it iterates all fixups
-void Image::forEachFixup(std::span<const MappedSegment> segments, void (^callback)(const Fixup& fixup, bool& stop)) const
-{
- const uint64_t prefLoadAddr = this->header()->preferredLoadAddress();
- uint16_t fwPointerFormat;
- uint32_t fwStartsCount;
- const uint32_t* fwStarts;
- if ( this->hasChainedFixups() ) {
- const ChainedFixups& chainedFixups = this->chainedFixups();
- // userland binary with LC_DYLD_CHAINED_FIXUPS or firmware with __chain_fixups section
- std::vector<uint64_t> segOffsetTable;
- if ( header()->isPreload() ) {
- // build segOffsetTable from chained fixups header
- for (int segIndex=0; ; ++segIndex) {
- const dyld_chained_starts_in_segment* segInfo = chainedFixups.startsForSegment(segIndex);
- if ( segInfo == nullptr )
- break;
- segOffsetTable.push_back(segInfo->segment_offset);
- }
- }
- chainedFixups.forEachFixupChainStartLocation(segments, ^(const void* chainStart, uint32_t segIndex, uint32_t pageIndex, uint32_t pageSize, const ChainedFixups::PointerFormat& pf, bool& stop) {
- pf.forEachFixupLocationInChain(chainStart, prefLoadAddr, &segments[segIndex], segOffsetTable, pageIndex, pageSize, callback);
- });
- }
- else if ( this->header()->hasFirmwareChainStarts(&fwPointerFormat, &fwStartsCount, &fwStarts) ) {
- // firmware binary with __TEXT,__chain_starts section
- // Note: for historical reasons firmware __chain_starts section use file-offsets from the start of __TEXT
- // but that can be changed with -fixup_chains_section_vm linker option. But which option is used is not
- // encoded in the binary, so we need a heuristic here.
- bool startOffsetsAreFileOffsets = true;
- if ( (fwStartsCount > 0) && (segments.back().fileOffset + segments.back().runtimeSize < fwStarts[fwStartsCount-1]) )
- startOffsetsAreFileOffsets = false;
-
- const ChainedFixups::PointerFormat& pf = ChainedFixups::PointerFormat::make(fwPointerFormat);
- for (uint32_t i=0; i < fwStartsCount; ++i) {
- const void* chainStart = nullptr;
- if ( startOffsetsAreFileOffsets ) {
- chainStart = ((uint8_t*)this->header()) + segments[0].fileOffset + fwStarts[i];
- }
- else {
- for (const MappedSegment& seg : segments) {
- uint32_t startOffset = fwStarts[i];
- if ( (seg.runtimeOffset <= startOffset) && (startOffset < seg.runtimeOffset+seg.runtimeSize) ) {
- uint64_t vmOffsetInSegment = startOffset - seg.runtimeOffset;
- chainStart = ((uint8_t*)this->header()) + seg.fileOffset + vmOffsetInSegment;
- break;
- }
- }
- }
- pf.forEachFixupLocationInChain(chainStart, prefLoadAddr, nullptr, {}, 0, 0, ^(const Fixup& fixup, bool& stop) {
- Fixup fixupWithSeg = fixup;
- uint64_t chainOffset = (uint8_t*)fixup.location - ((uint8_t*)this->header());
- // Note: firmware chains can cross segments, so we cannot pre-compute 'seg'
- for (size_t s=0; s < segments.size(); ++s) {
- if ( (segments[s].fileOffset <= chainOffset) && (chainOffset < segments[s].fileOffset+segments[s].runtimeSize) ) {
- fixupWithSeg.segment = &segments[s];
- break;
- }
- }
- callback(fixupWithSeg, stop);
- });
- }
- }
- else if ( this->header()->hasFirmwareRebaseRuns() ) {
- // firmware binary with __TEXT,__rebase_info section
- bool is64 = this->header()->is64();
- this->header()->forEachFirmwareRebaseRuns(^(uint32_t address, bool& stop) {
- // Note: __rebase_info addresses are vmaddrs
- const MappedSegment* seg = nullptr;
- uint64_t segOffset = 0;
- for (size_t s=0; s < segments.size(); ++s) {
- uint64_t segStartAddresss = prefLoadAddr+segments[s].runtimeOffset;
- if ( (segStartAddresss <= address) && (address < segStartAddresss+segments[s].runtimeSize) ) {
- seg = &segments[s];
- segOffset = address - segStartAddresss;
- break;
- }
- }
- if ( seg != nullptr ) {
- const void* loc = (uint8_t*)seg->content + segOffset;
- uint64_t targetVmAddr = is64 ? (*(uint64_t*)loc) : (*(uint32_t*)loc);
- Fixup fixup(loc, seg, targetVmAddr-prefLoadAddr);
- callback(fixup, stop);
- }
- });
- }
- else if ( this->header()->hasOpcodeFixups() ) {
- // userland binary with LC_DYLD_INFO
- uint32_t bindOrdinal = 0;
- if ( this->hasBindOpcodes() ) {
- bindOrdinal = this->bindOpcodes().forEachBindLocation(segments, bindOrdinal, callback);
- }
- if ( this->hasLazyBindOpcodes() ) {
- this->lazyBindOpcodes().forEachBindLocation(segments, bindOrdinal, callback);
- }
- if ( this->hasRebaseOpcodes() ) {
- this->rebaseOpcodes().forEachRebaseLocation(segments, prefLoadAddr, callback);
- }
- }
- else {
- // unsupported format
- }
-}
-
-void Image::forEachFilesetImage(void (^callback)(const Image& entryImage, std::string_view name, bool& stop)) const
-{
- int64_t slide = header()->getSlide();
- header()->forEachLoadCommandSafe(^(const load_command *cmd, bool &stop) {
- if (cmd->cmd == LC_FILESET_ENTRY) {
- const fileset_entry_command* app_cache_cmd = (const fileset_entry_command*)cmd;
- const char* name = (char*)app_cache_cmd + app_cache_cmd->entry_id.offset;
-
- void* entryStart = (void*)(app_cache_cmd->vmaddr + slide);
- size_t entrySize = _bufferSize - (size_t)((uint64_t)entryStart - (uint64_t)header());
- Image entryImage(entryStart, entrySize, MappingKind::wholeSliceMapped);
- callback(entryImage, name, stop);
- return;
- }
- });
-}
-
-std::span<const uint32_t> Image::indirectSymbolTable() const
-{
- uint32_t fileOffset;
- uint32_t count;
- if ( header()->hasIndirectSymbolTable(fileOffset, count) ) {
- return std::span<const uint32_t>((uint32_t*)(_linkeditBias + fileOffset), count);
- }
- return std::span<const uint32_t>();
-}
-
-std::span<uint8_t> Image::atomInfo() const
-{
- uint32_t fileOffset;
- uint32_t count;
- if ( header()->hasAtomInfo(fileOffset, count) ) {
- return std::span<uint8_t>((uint8_t*)(_linkeditBias + fileOffset), count);
- }
- return std::span<uint8_t>();
-}
-
-static void forEachPointerInSection(const Header* hdr, uint8_t sectionType, uint64_t prefLoadAddress,
- bool contentRebased, void (^callback)(uint32_t offset))
-{
- hdr->forEachSection(^(const Header::SectionInfo& sectInfo, bool& stop) {
- if ( (sectInfo.flags & SECTION_TYPE) == sectionType ) {
- const uint8_t* sectionContent = (uint8_t*)hdr + sectInfo.fileOffset;
- if ( hdr->inDyldCache() )
- sectionContent = (uint8_t*)(sectInfo.address + hdr->getSlide());
-
- if ( contentRebased ) {
- // in dyld, when this is called, the image is already rebased, so we can use pointers in section
- const uintptr_t* initsStart = (uintptr_t*)sectionContent;
- const uintptr_t* initsEnd = (uintptr_t*)((uint8_t*)sectionContent + sectInfo.size);
- for (const uintptr_t* p=initsStart; p < initsEnd; ++p) {
- uintptr_t anInit = *p;
- uint32_t anInitOffset = (uint32_t)(anInit - prefLoadAddress);
- callback(anInitOffset);
- }
- } else {
- if ( hdr->is64() ) {
- const uint64_t* initsStart = (uint64_t*)sectionContent;
- const uint64_t* initsEnd = (uint64_t*)((uint8_t*)sectionContent + sectInfo.size);
- for (const uint64_t* p=initsStart; p < initsEnd; ++p) {
- uint64_t anInit = *p;
- // FIXME: as a quick hack, the low 32-bits with either rebase opcodes or chained fixups is offset in image
- callback((uint32_t)anInit);
- }
- }
- else {
- const uint32_t* initsStart = (uint32_t*)sectionContent;
- const uint32_t* initsEnd = (uint32_t*)((uint8_t*)sectionContent + sectInfo.size);
- for (const uint32_t* p=initsStart; p < initsEnd; ++p) {
- uint32_t anInitOffset = *p;
- // FIXME: as a quick hack, the low 26-bits with either rebase opcodes or chained fixups is offset in image
- callback(anInitOffset & 0x03FFFFFF);
- }
- }
- }
- }
- });
-}
-
-void Image::forEachInitializer(bool contentRebased, void (^callback)(uint32_t offset)) const
-{
- const Header* hdr = header();
- uint64_t prefLoadAddress = hdr->preferredLoadAddress();
-
- // if dylib linked with -init linker option, that initializer is first
- hdr->forEachLoadCommandSafe(^(const load_command* cmd, bool& stop) {
- if ( cmd->cmd == LC_ROUTINES ) {
- const routines_command* routines = (routines_command*)cmd;
- uint64_t dashInit = routines->init_address;
- callback((uint32_t)(dashInit - prefLoadAddress));
- }
- else if ( cmd->cmd == LC_ROUTINES_64 ) {
- const routines_command_64* routines = (routines_command_64*)cmd;
- uint64_t dashInit = routines->init_address;
- callback((uint32_t)(dashInit - prefLoadAddress));
- }
- });
-
- // next any function pointers in __DATA,__mod_init_func section
- forEachPointerInSection(hdr, S_MOD_INIT_FUNC_POINTERS, prefLoadAddress, contentRebased, callback);
-
- // next any function pointers in __TEXT,__init_offsets
- hdr->forEachSection(^(const Header::SectionInfo& sectInfo, bool& stop) {
- if ( (sectInfo.flags & SECTION_TYPE) == S_INIT_FUNC_OFFSETS ) {
- const uint8_t* sectionContent = (uint8_t*)hdr + sectInfo.fileOffset;
- if ( hdr->inDyldCache() )
- sectionContent = (uint8_t*)(sectInfo.address + hdr->getSlide());
- const uint32_t* initsStart = (uint32_t*)sectionContent;
- const uint32_t* initsEnd = (uint32_t*)((uint8_t*)sectionContent + sectInfo.size);
- for (const uint32_t* p=initsStart; p < initsEnd; ++p) {
- uint32_t anInitOffset = *p;
- callback(anInitOffset);
- }
- }
- });
-}
-
-void Image::forEachClassicTerminator(bool contentRebased, void (^callback)(uint32_t offset)) const
-{
- uint64_t prefLoadAddress = header()->preferredLoadAddress();
-
- // any function pointers in __DATA,__mod_term_func section
- forEachPointerInSection(header(), S_MOD_TERM_FUNC_POINTERS, prefLoadAddress, contentRebased, callback);
-}
-
-
-
-} // namespace mach_o