ImageLoaderMachOCompressed.cpp [plain text]
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/fcntl.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <sys/param.h>
#include <mach/mach.h>
#include <mach/thread_status.h>
#include <mach-o/loader.h>
#include "ImageLoaderMachOCompressed.h"
#include "mach-o/dyld_images.h"
#if __LP64__
#define RELOC_SIZE 3
#define LC_SEGMENT_COMMAND LC_SEGMENT_64
#define LC_ROUTINES_COMMAND LC_ROUTINES_64
struct macho_segment_command : public segment_command_64 {};
struct macho_section : public section_64 {};
struct macho_routines_command : public routines_command_64 {};
#else
#define RELOC_SIZE 2
#define LC_SEGMENT_COMMAND LC_SEGMENT
#define LC_ROUTINES_COMMAND LC_ROUTINES
struct macho_segment_command : public segment_command {};
struct macho_section : public section {};
struct macho_routines_command : public routines_command {};
#endif
static uintptr_t read_uleb128(const uint8_t*& p, const uint8_t* end)
{
uint64_t result = 0;
int bit = 0;
do {
if (p == end)
dyld::throwf("malformed uleb128");
uint64_t slice = *p & 0x7f;
if (bit > 63)
dyld::throwf("uleb128 too big for uint64, bit=%d, result=0x%0llX", bit, result);
else {
result |= (slice << bit);
bit += 7;
}
} while (*p++ & 0x80);
return result;
}
static intptr_t read_sleb128(const uint8_t*& p, const uint8_t* end)
{
int64_t result = 0;
int bit = 0;
uint8_t byte;
do {
if (p == end)
throw "malformed sleb128";
byte = *p++;
result |= ((byte & 0x7f) << bit);
bit += 7;
} while (byte & 0x80);
if ( (byte & 0x40) != 0 )
result |= (-1LL) << bit;
return result;
}
ImageLoaderMachOCompressed* ImageLoaderMachOCompressed::instantiateMainExecutable(const macho_header* mh, uintptr_t slide, const char* path,
unsigned int segCount, unsigned int libCount, const LinkContext& context)
{
ImageLoaderMachOCompressed* image = ImageLoaderMachOCompressed::instantiateStart(mh, path, segCount, libCount);
image->setSlide(slide);
if ( slide != 0 )
fgNextPIEDylibAddress = (uintptr_t)image->getEnd();
image->setNeverUnload();
image->instantiateFinish(context);
image->setMapped(context);
if ( context.verboseMapping ) {
dyld::log("dyld: Main executable mapped %s\n", path);
for(unsigned int i=0, e=image->segmentCount(); i < e; ++i) {
const char* name = image->segName(i);
if ( (strcmp(name, "__PAGEZERO") == 0) || (strcmp(name, "__UNIXSTACK") == 0) )
dyld::log("%18s at 0x%08lX->0x%08lX\n", name, image->segPreferredLoadAddress(i), image->segPreferredLoadAddress(i)+image->segSize(i));
else
dyld::log("%18s at 0x%08lX->0x%08lX\n", name, image->segActualLoadAddress(i), image->segActualEndAddress(i));
}
}
return image;
}
ImageLoaderMachOCompressed* ImageLoaderMachOCompressed::instantiateFromFile(const char* path, int fd, const uint8_t* fileData,
uint64_t offsetInFat, uint64_t lenInFat, const struct stat& info,
unsigned int segCount, unsigned int libCount,
const struct linkedit_data_command* codeSigCmd, const LinkContext& context)
{
ImageLoaderMachOCompressed* image = ImageLoaderMachOCompressed::instantiateStart((macho_header*)fileData, path, segCount, libCount);
try {
image->setFileInfo(info.st_dev, info.st_ino, info.st_mtime);
#if CODESIGNING_SUPPORT
if ( codeSigCmd != NULL )
image->loadCodeSignature(codeSigCmd, fd, offsetInFat);
#endif
image->mapSegments(fd, offsetInFat, lenInFat, info.st_size, context);
image->instantiateFinish(context);
const char* installName = image->getInstallPath();
if ( (installName != NULL) && (strcmp(installName, path) == 0) && (path[0] == '/') )
image->setPathUnowned(installName);
#if __MAC_OS_X_VERSION_MIN_REQUIRED
else if ( (installName != NULL) && (strcmp(path, "/usr/lib/libgcc_s.1.dylib") == 0) && (strcmp(installName, "/usr/lib/libSystem.B.dylib") == 0) )
image->setPathUnowned("/usr/lib/libSystem.B.dylib");
#endif
else if ( path[0] != '/' ) {
char realPath[MAXPATHLEN];
if ( realpath(path, realPath) != NULL )
image->setPath(realPath);
else
image->setPath(path);
}
else
image->setPath(path);
image->setMapped(context);
if ( !context.preFetchDisabled && !image->isPrebindable()) {
image->preFetchDATA(fd, offsetInFat, context);
image->markSequentialLINKEDIT(context);
}
}
catch (...) {
delete image;
throw;
}
return image;
}
ImageLoaderMachOCompressed* ImageLoaderMachOCompressed::instantiateFromCache(const macho_header* mh, const char* path, long slide,
const struct stat& info, unsigned int segCount,
unsigned int libCount, const LinkContext& context)
{
ImageLoaderMachOCompressed* image = ImageLoaderMachOCompressed::instantiateStart(mh, path, segCount, libCount);
try {
image->setFileInfo(info.st_dev, info.st_ino, info.st_mtime);
image->fInSharedCache = true;
image->fGoodFirstSegment = true;
image->setNeverUnload();
image->setSlide(slide);
if ( context.verboseMapping ) {
dyld::log("dyld: Using shared cached for %s\n", path);
for(unsigned int i=0; i < image->fSegmentsCount; ++i) {
dyld::log("%18s at 0x%08lX->0x%08lX\n", image->segName(i), image->segActualLoadAddress(i), image->segActualEndAddress(i));
}
}
image->instantiateFinish(context);
image->setMapped(context);
}
catch (...) {
delete image;
throw;
}
return image;
}
ImageLoaderMachOCompressed* ImageLoaderMachOCompressed::instantiateFromMemory(const char* moduleName, const macho_header* mh, uint64_t len,
unsigned int segCount, unsigned int libCount, const LinkContext& context)
{
ImageLoaderMachOCompressed* image = ImageLoaderMachOCompressed::instantiateStart(mh, moduleName, segCount, libCount);
try {
if ( mh->filetype == MH_EXECUTE )
throw "can't load another MH_EXECUTE";
image->mapSegments((const void*)mh, len, context);
image->setNeverUnload();
if ( moduleName != NULL )
image->setPath(moduleName);
image->instantiateFinish(context);
image->setMapped(context);
}
catch (...) {
delete image;
throw;
}
return image;
}
ImageLoaderMachOCompressed::ImageLoaderMachOCompressed(const macho_header* mh, const char* path, unsigned int segCount,
uint32_t segOffsets[], unsigned int libCount)
: ImageLoaderMachO(mh, path, segCount, segOffsets, libCount), fDyldInfo(NULL)
{
}
ImageLoaderMachOCompressed::~ImageLoaderMachOCompressed()
{
destroy();
}
ImageLoaderMachOCompressed* ImageLoaderMachOCompressed::instantiateStart(const macho_header* mh, const char* path,
unsigned int segCount, unsigned int libCount)
{
size_t size = sizeof(ImageLoaderMachOCompressed) + segCount * sizeof(uint32_t) + libCount * sizeof(ImageLoader*);
ImageLoaderMachOCompressed* allocatedSpace = static_cast<ImageLoaderMachOCompressed*>(malloc(size));
if ( allocatedSpace == NULL )
throw "malloc failed";
uint32_t* segOffsets = ((uint32_t*)(((uint8_t*)allocatedSpace) + sizeof(ImageLoaderMachOCompressed)));
bzero(&segOffsets[segCount], libCount*sizeof(void*)); return new (allocatedSpace) ImageLoaderMachOCompressed(mh, path, segCount, segOffsets, libCount);
}
void ImageLoaderMachOCompressed::instantiateFinish(const LinkContext& context)
{
this->parseLoadCmds();
}
uint32_t* ImageLoaderMachOCompressed::segmentCommandOffsets() const
{
return ((uint32_t*)(((uint8_t*)this) + sizeof(ImageLoaderMachOCompressed)));
}
ImageLoader* ImageLoaderMachOCompressed::libImage(unsigned int libIndex) const
{
const uintptr_t* images = ((uintptr_t*)(((uint8_t*)this) + sizeof(ImageLoaderMachOCompressed) + fSegmentsCount*sizeof(uint32_t)));
return (ImageLoader*)(images[libIndex] & (-4));
}
bool ImageLoaderMachOCompressed::libReExported(unsigned int libIndex) const
{
const uintptr_t* images = ((uintptr_t*)(((uint8_t*)this) + sizeof(ImageLoaderMachOCompressed) + fSegmentsCount*sizeof(uint32_t)));
return ((images[libIndex] & 1) != 0);
}
bool ImageLoaderMachOCompressed::libIsUpward(unsigned int libIndex) const
{
const uintptr_t* images = ((uintptr_t*)(((uint8_t*)this) + sizeof(ImageLoaderMachOCompressed) + fSegmentsCount*sizeof(uint32_t)));
return ((images[libIndex] & 2) != 0);
}
void ImageLoaderMachOCompressed::setLibImage(unsigned int libIndex, ImageLoader* image, bool reExported, bool upward)
{
uintptr_t* images = ((uintptr_t*)(((uint8_t*)this) + sizeof(ImageLoaderMachOCompressed) + fSegmentsCount*sizeof(uint32_t)));
uintptr_t value = (uintptr_t)image;
if ( reExported )
value |= 1;
if ( upward )
value |= 2;
images[libIndex] = value;
}
void ImageLoaderMachOCompressed::markFreeLINKEDIT(const LinkContext& context)
{
markLINKEDIT(context, MADV_FREE);
}
void ImageLoaderMachOCompressed::markSequentialLINKEDIT(const LinkContext& context)
{
markLINKEDIT(context, MADV_SEQUENTIAL);
}
void ImageLoaderMachOCompressed::markLINKEDIT(const LinkContext& context, int advise)
{
uintptr_t start = 0;
if ( (fSlide != 0) && (fDyldInfo->rebase_size != 0) )
start = (uintptr_t)fLinkEditBase + fDyldInfo->rebase_off;
else if ( fDyldInfo->bind_off != 0 )
start = (uintptr_t)fLinkEditBase + fDyldInfo->bind_off;
else
return;
uintptr_t end = 0;
if ( fDyldInfo->bind_off != 0 )
end = (uintptr_t)fLinkEditBase + fDyldInfo->bind_off + fDyldInfo->bind_size;
else if ( fDyldInfo->rebase_off != 0 )
end = (uintptr_t)fLinkEditBase + fDyldInfo->rebase_off + fDyldInfo->rebase_size;
else
return;
start = start & (-4096);
end = (end + 4095) & (-4096);
if ( (end-start) <= 4096 )
return;
madvise((void*)start, end-start, advise);
if ( context.verboseMapping ) {
const char* adstr = "sequential";
if ( advise == MADV_FREE )
adstr = "free";
dyld::log("%18s %s 0x%0lX -> 0x%0lX for %s\n", "__LINKEDIT", adstr, start, end-1, this->getPath());
}
}
void ImageLoaderMachOCompressed::rebaseAt(const LinkContext& context, uintptr_t addr, uintptr_t slide, uint8_t type)
{
uintptr_t* locationToFix = (uintptr_t*)addr;
switch (type) {
case REBASE_TYPE_POINTER:
*locationToFix += slide;
break;
case REBASE_TYPE_TEXT_ABSOLUTE32:
*locationToFix += slide;
break;
default:
dyld::throwf("bad rebase type %d", type);
}
}
void ImageLoaderMachOCompressed::throwBadRebaseAddress(uintptr_t address, uintptr_t segmentEndAddress, int segmentIndex,
const uint8_t* startOpcodes, const uint8_t* endOpcodes, const uint8_t* pos)
{
dyld::throwf("malformed rebase opcodes (%ld/%ld): address 0x%08lX is beyond end of segment %s (0x%08lX -> 0x%08lX)",
(intptr_t)(pos-startOpcodes), (intptr_t)(endOpcodes-startOpcodes), address, segName(segmentIndex),
segActualLoadAddress(segmentIndex), segmentEndAddress);
}
void ImageLoaderMachOCompressed::rebase(const LinkContext& context)
{
CRSetCrashLogMessage2(this->getPath());
const uintptr_t slide = this->fSlide;
const uint8_t* const start = fLinkEditBase + fDyldInfo->rebase_off;
const uint8_t* const end = &start[fDyldInfo->rebase_size];
const uint8_t* p = start;
try {
uint8_t type = 0;
int segmentIndex = 0;
uintptr_t address = segActualLoadAddress(0);
uintptr_t segmentEndAddress = segActualEndAddress(0);
uint32_t count;
uint32_t skip;
bool done = false;
while ( !done && (p < end) ) {
uint8_t immediate = *p & REBASE_IMMEDIATE_MASK;
uint8_t opcode = *p & REBASE_OPCODE_MASK;
++p;
switch (opcode) {
case REBASE_OPCODE_DONE:
done = true;
break;
case REBASE_OPCODE_SET_TYPE_IMM:
type = immediate;
break;
case REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
segmentIndex = immediate;
if ( segmentIndex > fSegmentsCount )
dyld::throwf("REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is too large (%d)\n",
segmentIndex, fSegmentsCount);
address = segActualLoadAddress(segmentIndex) + read_uleb128(p, end);
segmentEndAddress = segActualEndAddress(segmentIndex);
break;
case REBASE_OPCODE_ADD_ADDR_ULEB:
address += read_uleb128(p, end);
break;
case REBASE_OPCODE_ADD_ADDR_IMM_SCALED:
address += immediate*sizeof(uintptr_t);
break;
case REBASE_OPCODE_DO_REBASE_IMM_TIMES:
for (int i=0; i < immediate; ++i) {
if ( address >= segmentEndAddress )
throwBadRebaseAddress(address, segmentEndAddress, segmentIndex, start, end, p);
rebaseAt(context, address, slide, type);
address += sizeof(uintptr_t);
}
fgTotalRebaseFixups += immediate;
break;
case REBASE_OPCODE_DO_REBASE_ULEB_TIMES:
count = read_uleb128(p, end);
for (uint32_t i=0; i < count; ++i) {
if ( address >= segmentEndAddress )
throwBadRebaseAddress(address, segmentEndAddress, segmentIndex, start, end, p);
rebaseAt(context, address, slide, type);
address += sizeof(uintptr_t);
}
fgTotalRebaseFixups += count;
break;
case REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB:
if ( address >= segmentEndAddress )
throwBadRebaseAddress(address, segmentEndAddress, segmentIndex, start, end, p);
rebaseAt(context, address, slide, type);
address += read_uleb128(p, end) + sizeof(uintptr_t);
++fgTotalRebaseFixups;
break;
case REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_ULEB:
count = read_uleb128(p, end);
skip = read_uleb128(p, end);
for (uint32_t i=0; i < count; ++i) {
if ( address >= segmentEndAddress )
throwBadRebaseAddress(address, segmentEndAddress, segmentIndex, start, end, p);
rebaseAt(context, address, slide, type);
address += skip + sizeof(uintptr_t);
}
fgTotalRebaseFixups += count;
break;
default:
dyld::throwf("bad rebase opcode %d", *p);
}
}
}
catch (const char* msg) {
const char* newMsg = dyld::mkstringf("%s in %s", msg, this->getPath());
free((void*)msg);
throw newMsg;
}
CRSetCrashLogMessage2(NULL);
}
const uint8_t* ImageLoaderMachOCompressed::trieWalk(const uint8_t* start, const uint8_t* end, const char* s)
{
const uint8_t* p = start;
while ( p != NULL ) {
uint32_t terminalSize = *p++;
if ( terminalSize > 127 ) {
--p;
terminalSize = read_uleb128(p, end);
}
if ( (*s == '\0') && (terminalSize != 0) ) {
return p;
}
const uint8_t* children = p + terminalSize;
uint8_t childrenRemaining = *children++;
p = children;
uint32_t nodeOffset = 0;
for (; childrenRemaining > 0; --childrenRemaining) {
const char* ss = s;
bool wrongEdge = false;
char c = *p;
while ( c != '\0' ) {
if ( !wrongEdge ) {
if ( c != *ss )
wrongEdge = true;
++ss;
}
++p;
c = *p;
}
if ( wrongEdge ) {
++p; while ( (*p & 0x80) != 0 )
++p;
++p; }
else {
++p;
nodeOffset = read_uleb128(p, end);
s = ss;
break;
}
}
if ( nodeOffset != 0 )
p = &start[nodeOffset];
else
p = NULL;
}
return NULL;
}
const ImageLoader::Symbol* ImageLoaderMachOCompressed::findExportedSymbol(const char* symbol, const ImageLoader** foundIn) const
{
if ( fDyldInfo->export_size == 0 )
return NULL;
#if LOG_BINDINGS
dyld::logBindings("%s: %s\n", this->getShortName(), symbol);
#endif
++ImageLoaderMachO::fgSymbolTrieSearchs;
const uint8_t* start = &fLinkEditBase[fDyldInfo->export_off];
const uint8_t* end = &start[fDyldInfo->export_size];
const uint8_t* foundNodeStart = this->trieWalk(start, end, symbol);
if ( foundNodeStart != NULL ) {
const uint8_t* p = foundNodeStart;
const uint32_t flags = read_uleb128(p, end);
if ( flags & EXPORT_SYMBOL_FLAGS_REEXPORT ) {
const uint32_t ordinal = read_uleb128(p, end);
const char* importedName = (char*)p;
if ( importedName[0] == '\0' )
importedName = symbol;
if ( (ordinal > 0) && (ordinal <= libraryCount()) ) {
const ImageLoader* reexportedFrom = libImage(ordinal-1);
return reexportedFrom->findExportedSymbol(importedName, true, foundIn);
}
else {
}
}
else {
if ( foundIn != NULL )
*foundIn = (ImageLoader*)this;
return (Symbol*)foundNodeStart;
}
}
return NULL;
}
bool ImageLoaderMachOCompressed::containsSymbol(const void* addr) const
{
const uint8_t* start = &fLinkEditBase[fDyldInfo->export_off];
const uint8_t* end = &start[fDyldInfo->export_size];
return ( (start <= addr) && (addr < end) );
}
uintptr_t ImageLoaderMachOCompressed::exportedSymbolAddress(const LinkContext& context, const Symbol* symbol, bool runResolver) const
{
const uint8_t* exportNode = (uint8_t*)symbol;
const uint8_t* exportTrieStart = fLinkEditBase + fDyldInfo->export_off;
const uint8_t* exportTrieEnd = exportTrieStart + fDyldInfo->export_size;
if ( (exportNode < exportTrieStart) || (exportNode > exportTrieEnd) )
throw "symbol is not in trie";
uint32_t flags = read_uleb128(exportNode, exportTrieEnd);
if ( (flags & EXPORT_SYMBOL_FLAGS_KIND_MASK) == EXPORT_SYMBOL_FLAGS_KIND_REGULAR ) {
if ( runResolver && (flags & EXPORT_SYMBOL_FLAGS_STUB_AND_RESOLVER) ) {
read_uleb128(exportNode, exportTrieEnd); typedef uintptr_t (*ResolverProc)(void);
ResolverProc resolver = (ResolverProc)(read_uleb128(exportNode, exportTrieEnd) + (uintptr_t)fMachOData);
uintptr_t result = (*resolver)();
if ( context.verboseBind )
dyld::log("dyld: resolver at %p returned 0x%08lX\n", resolver, result);
return result;
}
return read_uleb128(exportNode, exportTrieEnd) + (uintptr_t)fMachOData;
}
else if ( (flags & EXPORT_SYMBOL_FLAGS_KIND_MASK) == EXPORT_SYMBOL_FLAGS_KIND_THREAD_LOCAL ) {
if ( flags & EXPORT_SYMBOL_FLAGS_STUB_AND_RESOLVER )
dyld::throwf("unsupported exported symbol kind. flags=%d at node=%p", flags, symbol);
return read_uleb128(exportNode, exportTrieEnd) + (uintptr_t)fMachOData;
}
else
dyld::throwf("unsupported exported symbol kind. flags=%d at node=%p", flags, symbol);
}
bool ImageLoaderMachOCompressed::exportedSymbolIsWeakDefintion(const Symbol* symbol) const
{
const uint8_t* exportNode = (uint8_t*)symbol;
const uint8_t* exportTrieStart = fLinkEditBase + fDyldInfo->export_off;
const uint8_t* exportTrieEnd = exportTrieStart + fDyldInfo->export_size;
if ( (exportNode < exportTrieStart) || (exportNode > exportTrieEnd) )
throw "symbol is not in trie";
uint32_t flags = read_uleb128(exportNode, exportTrieEnd);
return ( flags & EXPORT_SYMBOL_FLAGS_WEAK_DEFINITION );
}
const char* ImageLoaderMachOCompressed::exportedSymbolName(const Symbol* symbol) const
{
throw "NSNameOfSymbol() not supported with compressed LINKEDIT";
}
unsigned int ImageLoaderMachOCompressed::exportedSymbolCount() const
{
throw "NSSymbolDefinitionCountInObjectFileImage() not supported with compressed LINKEDIT";
}
const ImageLoader::Symbol* ImageLoaderMachOCompressed::exportedSymbolIndexed(unsigned int index) const
{
throw "NSSymbolDefinitionNameInObjectFileImage() not supported with compressed LINKEDIT";
}
unsigned int ImageLoaderMachOCompressed::importedSymbolCount() const
{
throw "NSSymbolReferenceCountInObjectFileImage() not supported with compressed LINKEDIT";
}
const ImageLoader::Symbol* ImageLoaderMachOCompressed::importedSymbolIndexed(unsigned int index) const
{
throw "NSSymbolReferenceCountInObjectFileImage() not supported with compressed LINKEDIT";
}
const char* ImageLoaderMachOCompressed::importedSymbolName(const Symbol* symbol) const
{
throw "NSSymbolReferenceNameInObjectFileImage() not supported with compressed LINKEDIT";
}
uintptr_t ImageLoaderMachOCompressed::resolveFlat(const LinkContext& context, const char* symbolName, bool weak_import,
bool runResolver, const ImageLoader** foundIn)
{
const Symbol* sym;
if ( context.flatExportFinder(symbolName, &sym, foundIn) ) {
if ( (*foundIn != this) && !(*foundIn)->neverUnload() )
this->addDynamicReference(*foundIn);
return (*foundIn)->getExportedSymbolAddress(sym, context, this, runResolver);
}
if ( this->isBundle() && this->hasHiddenExports() ) {
sym = this->ImageLoaderMachO::findExportedSymbol(symbolName, false, foundIn);
if ( sym != NULL )
return (*foundIn)->getExportedSymbolAddress(sym, context, this, runResolver);
}
if ( weak_import ) {
return 0;
}
throwSymbolNotFound(context, symbolName, this->getPath(), "flat namespace");
}
uintptr_t ImageLoaderMachOCompressed::resolveTwolevel(const LinkContext& context, const ImageLoader* targetImage, bool weak_import,
const char* symbolName, bool runResolver, const ImageLoader** foundIn)
{
const Symbol* sym = targetImage->findExportedSymbol(symbolName, true, foundIn);
if ( sym != NULL ) {
return (*foundIn)->getExportedSymbolAddress(sym, context, this, runResolver);
}
if ( weak_import ) {
return 0;
}
throwSymbolNotFound(context, symbolName, this->getPath(), targetImage->getPath());
}
uintptr_t ImageLoaderMachOCompressed::resolve(const LinkContext& context, const char* symbolName,
uint8_t symboFlags, int libraryOrdinal, const ImageLoader** targetImage,
LastLookup* last, bool runResolver)
{
*targetImage = NULL;
if ( last != NULL ) {
if ( (last->ordinal == libraryOrdinal)
&& (last->flags == symboFlags)
&& (last->name == symbolName) ) {
*targetImage = last->foundIn;
return last->result;
}
}
bool weak_import = (symboFlags & BIND_SYMBOL_FLAGS_WEAK_IMPORT);
uintptr_t symbolAddress;
if ( context.bindFlat || (libraryOrdinal == BIND_SPECIAL_DYLIB_FLAT_LOOKUP) ) {
symbolAddress = this->resolveFlat(context, symbolName, weak_import, runResolver, targetImage);
}
else {
if ( libraryOrdinal == BIND_SPECIAL_DYLIB_MAIN_EXECUTABLE ) {
*targetImage = context.mainExecutable;
}
else if ( libraryOrdinal == BIND_SPECIAL_DYLIB_SELF ) {
*targetImage = this;
}
else if ( libraryOrdinal <= 0 ) {
dyld::throwf("bad mach-o binary, unknown special library ordinal (%u) too big for symbol %s in %s",
libraryOrdinal, symbolName, this->getPath());
}
else if ( (unsigned)libraryOrdinal <= libraryCount() ) {
*targetImage = libImage(libraryOrdinal-1);
}
else {
dyld::throwf("bad mach-o binary, library ordinal (%u) too big (max %u) for symbol %s in %s",
libraryOrdinal, libraryCount(), symbolName, this->getPath());
}
if ( *targetImage == NULL ) {
if ( weak_import ) {
symbolAddress = 0;
}
else {
dyld::throwf("can't resolve symbol %s in %s because dependent dylib #%d could not be loaded",
symbolName, this->getPath(), libraryOrdinal);
}
}
else {
symbolAddress = resolveTwolevel(context, *targetImage, weak_import, symbolName, runResolver, targetImage);
}
}
if ( last != NULL ) {
last->ordinal = libraryOrdinal;
last->flags = symboFlags;
last->name = symbolName;
last->foundIn = *targetImage;
last->result = symbolAddress;
}
return symbolAddress;
}
uintptr_t ImageLoaderMachOCompressed::bindAt(const LinkContext& context, uintptr_t addr, uint8_t type, const char* symbolName,
uint8_t symboFlags, intptr_t addend, int libraryOrdinal, const char* msg,
LastLookup* last, bool runResolver)
{
const ImageLoader* targetImage;
uintptr_t symbolAddress;
symbolAddress = this->resolve(context, symbolName, symboFlags, libraryOrdinal, &targetImage, last, runResolver);
return this->bindLocation(context, addr, symbolAddress, targetImage, type, symbolName, addend, msg);
}
void ImageLoaderMachOCompressed::throwBadBindingAddress(uintptr_t address, uintptr_t segmentEndAddress, int segmentIndex,
const uint8_t* startOpcodes, const uint8_t* endOpcodes, const uint8_t* pos)
{
dyld::throwf("malformed binding opcodes (%ld/%ld): address 0x%08lX is beyond end of segment %s (0x%08lX -> 0x%08lX)",
(intptr_t)(pos-startOpcodes), (intptr_t)(endOpcodes-startOpcodes), address, segName(segmentIndex),
segActualLoadAddress(segmentIndex), segmentEndAddress);
}
void ImageLoaderMachOCompressed::doBind(const LinkContext& context, bool forceLazysBound)
{
CRSetCrashLogMessage2(this->getPath());
if ( this->usablePrebinding(context) ) {
}
else {
#if TEXT_RELOC_SUPPORT
if ( fTextSegmentBinds )
this->makeTextSegmentWritable(context, true);
#endif
eachBind(context, &ImageLoaderMachOCompressed::bindAt);
#if TEXT_RELOC_SUPPORT
if ( fTextSegmentBinds )
this->makeTextSegmentWritable(context, false);
#endif
if ( forceLazysBound || fInSharedCache )
this->doBindJustLazies(context);
if ( fInSharedCache )
this->updateOptimizedLazyPointers(context);
if ( !context.preFetchDisabled )
this->markFreeLINKEDIT(context);
}
this->setupLazyPointerHandler(context);
CRSetCrashLogMessage2(NULL);
}
void ImageLoaderMachOCompressed::doBindJustLazies(const LinkContext& context)
{
eachLazyBind(context, &ImageLoaderMachOCompressed::bindAt);
}
void ImageLoaderMachOCompressed::eachBind(const LinkContext& context, bind_handler handler)
{
try {
uint8_t type = 0;
int segmentIndex = 0;
uintptr_t address = segActualLoadAddress(0);
uintptr_t segmentEndAddress = segActualEndAddress(0);
const char* symbolName = NULL;
uint8_t symboFlags = 0;
int libraryOrdinal = 0;
intptr_t addend = 0;
uint32_t count;
uint32_t skip;
LastLookup last = { 0, 0, NULL, 0, NULL };
const uint8_t* const start = fLinkEditBase + fDyldInfo->bind_off;
const uint8_t* const end = &start[fDyldInfo->bind_size];
const uint8_t* p = start;
bool done = false;
while ( !done && (p < end) ) {
uint8_t immediate = *p & BIND_IMMEDIATE_MASK;
uint8_t opcode = *p & BIND_OPCODE_MASK;
++p;
switch (opcode) {
case BIND_OPCODE_DONE:
done = true;
break;
case BIND_OPCODE_SET_DYLIB_ORDINAL_IMM:
libraryOrdinal = immediate;
break;
case BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB:
libraryOrdinal = read_uleb128(p, end);
break;
case BIND_OPCODE_SET_DYLIB_SPECIAL_IMM:
if ( immediate == 0 )
libraryOrdinal = 0;
else {
int8_t signExtended = BIND_OPCODE_MASK | immediate;
libraryOrdinal = signExtended;
}
break;
case BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
symbolName = (char*)p;
symboFlags = immediate;
while (*p != '\0')
++p;
++p;
break;
case BIND_OPCODE_SET_TYPE_IMM:
type = immediate;
break;
case BIND_OPCODE_SET_ADDEND_SLEB:
addend = read_sleb128(p, end);
break;
case BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
segmentIndex = immediate;
if ( segmentIndex > fSegmentsCount )
dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is too large (%d)\n",
segmentIndex, fSegmentsCount);
address = segActualLoadAddress(segmentIndex) + read_uleb128(p, end);
segmentEndAddress = segActualEndAddress(segmentIndex);
break;
case BIND_OPCODE_ADD_ADDR_ULEB:
address += read_uleb128(p, end);
break;
case BIND_OPCODE_DO_BIND:
if ( address >= segmentEndAddress )
throwBadBindingAddress(address, segmentEndAddress, segmentIndex, start, end, p);
(this->*handler)(context, address, type, symbolName, symboFlags, addend, libraryOrdinal, "", &last, false);
address += sizeof(intptr_t);
break;
case BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB:
if ( address >= segmentEndAddress )
throwBadBindingAddress(address, segmentEndAddress, segmentIndex, start, end, p);
(this->*handler)(context, address, type, symbolName, symboFlags, addend, libraryOrdinal, "", &last, false);
address += read_uleb128(p, end) + sizeof(intptr_t);
break;
case BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED:
if ( address >= segmentEndAddress )
throwBadBindingAddress(address, segmentEndAddress, segmentIndex, start, end, p);
(this->*handler)(context, address, type, symbolName, symboFlags, addend, libraryOrdinal, "", &last, false);
address += immediate*sizeof(intptr_t) + sizeof(intptr_t);
break;
case BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB:
count = read_uleb128(p, end);
skip = read_uleb128(p, end);
for (uint32_t i=0; i < count; ++i) {
if ( address >= segmentEndAddress )
throwBadBindingAddress(address, segmentEndAddress, segmentIndex, start, end, p);
(this->*handler)(context, address, type, symbolName, symboFlags, addend, libraryOrdinal, "", &last, false);
address += skip + sizeof(intptr_t);
}
break;
default:
dyld::throwf("bad bind opcode %d in bind info", *p);
}
}
}
catch (const char* msg) {
const char* newMsg = dyld::mkstringf("%s in %s", msg, this->getPath());
free((void*)msg);
throw newMsg;
}
}
void ImageLoaderMachOCompressed::eachLazyBind(const LinkContext& context, bind_handler handler)
{
try {
uint8_t type = BIND_TYPE_POINTER;
int segmentIndex = 0;
uintptr_t address = segActualLoadAddress(0);
uintptr_t segmentEndAddress = segActualEndAddress(0);
const char* symbolName = NULL;
uint8_t symboFlags = 0;
int libraryOrdinal = 0;
intptr_t addend = 0;
const uint8_t* const start = fLinkEditBase + fDyldInfo->lazy_bind_off;
const uint8_t* const end = &start[fDyldInfo->lazy_bind_size];
const uint8_t* p = start;
bool done = false;
while ( !done && (p < end) ) {
uint8_t immediate = *p & BIND_IMMEDIATE_MASK;
uint8_t opcode = *p & BIND_OPCODE_MASK;
++p;
switch (opcode) {
case BIND_OPCODE_DONE:
break;
case BIND_OPCODE_SET_DYLIB_ORDINAL_IMM:
libraryOrdinal = immediate;
break;
case BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB:
libraryOrdinal = read_uleb128(p, end);
break;
case BIND_OPCODE_SET_DYLIB_SPECIAL_IMM:
if ( immediate == 0 )
libraryOrdinal = 0;
else {
int8_t signExtended = BIND_OPCODE_MASK | immediate;
libraryOrdinal = signExtended;
}
break;
case BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
symbolName = (char*)p;
symboFlags = immediate;
while (*p != '\0')
++p;
++p;
break;
case BIND_OPCODE_SET_TYPE_IMM:
type = immediate;
break;
case BIND_OPCODE_SET_ADDEND_SLEB:
addend = read_sleb128(p, end);
break;
case BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
segmentIndex = immediate;
if ( segmentIndex > fSegmentsCount )
dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is too large (%d)\n",
segmentIndex, fSegmentsCount);
address = segActualLoadAddress(segmentIndex) + read_uleb128(p, end);
segmentEndAddress = segActualEndAddress(segmentIndex);
break;
case BIND_OPCODE_ADD_ADDR_ULEB:
address += read_uleb128(p, end);
break;
case BIND_OPCODE_DO_BIND:
if ( address >= segmentEndAddress )
throwBadBindingAddress(address, segmentEndAddress, segmentIndex, start, end, p);
(this->*handler)(context, address, type, symbolName, symboFlags, addend, libraryOrdinal, "lazy forced", NULL, true);
address += sizeof(intptr_t);
break;
case BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB:
case BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED:
case BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB:
default:
dyld::throwf("bad lazy bind opcode %d", *p);
}
}
}
catch (const char* msg) {
const char* newMsg = dyld::mkstringf("%s in %s", msg, this->getPath());
free((void*)msg);
throw newMsg;
}
}
uintptr_t ImageLoaderMachOCompressed::doBindLazySymbol(uintptr_t* lazyPointer, const LinkContext& context)
{
const macho_nlist* symbolTable = NULL;
const char* symbolTableStrings = NULL;
const dysymtab_command* dynSymbolTable = NULL;
const uint32_t cmd_count = ((macho_header*)fMachOData)->ncmds;
const struct load_command* const cmds = (struct load_command*)&fMachOData[sizeof(macho_header)];
const struct load_command* cmd = cmds;
for (uint32_t i = 0; i < cmd_count; ++i) {
switch (cmd->cmd) {
case LC_SYMTAB:
{
const struct symtab_command* symtab = (struct symtab_command*)cmd;
symbolTableStrings = (const char*)&fLinkEditBase[symtab->stroff];
symbolTable = (macho_nlist*)(&fLinkEditBase[symtab->symoff]);
}
break;
case LC_DYSYMTAB:
dynSymbolTable = (struct dysymtab_command*)cmd;
break;
}
cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
}
if ( (symbolTable == NULL) || (dynSymbolTable == NULL) )
dyld::throwf("classic lazy binding used with compressed LINKEDIT at %p in image %s", lazyPointer, this->getPath());
const bool twoLevel = this->usesTwoLevelNameSpace();
const uint32_t* const indirectTable = (uint32_t*)&fLinkEditBase[dynSymbolTable->indirectsymoff];
cmd = cmds;
for (uint32_t i = 0; i < cmd_count; ++i) {
switch (cmd->cmd) {
case LC_SEGMENT_COMMAND:
{
const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
const struct macho_section* const sectionsStart = (struct macho_section*)((char*)seg + sizeof(struct macho_segment_command));
const struct macho_section* const sectionsEnd = §ionsStart[seg->nsects];
for (const struct macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
const uint8_t type = sect->flags & SECTION_TYPE;
uint32_t symbolIndex = INDIRECT_SYMBOL_LOCAL;
if ( type == S_LAZY_SYMBOL_POINTERS ) {
const uint32_t pointerCount = sect->size / sizeof(uintptr_t);
uintptr_t* const symbolPointers = (uintptr_t*)(sect->addr + fSlide);
if ( (lazyPointer >= symbolPointers) && (lazyPointer < &symbolPointers[pointerCount]) ) {
const uint32_t indirectTableOffset = sect->reserved1;
const uint32_t lazyIndex = lazyPointer - symbolPointers;
symbolIndex = indirectTable[indirectTableOffset + lazyIndex];
}
}
if ( (symbolIndex != INDIRECT_SYMBOL_ABS) && (symbolIndex != INDIRECT_SYMBOL_LOCAL) ) {
const macho_nlist* symbol = &symbolTable[symbolIndex];
const char* symbolName = &symbolTableStrings[symbol->n_un.n_strx];
int libraryOrdinal = GET_LIBRARY_ORDINAL(symbol->n_desc);
if ( !twoLevel || context.bindFlat )
libraryOrdinal = BIND_SPECIAL_DYLIB_FLAT_LOOKUP;
uintptr_t ptrToBind = (uintptr_t)lazyPointer;
uintptr_t symbolAddr = bindAt(context, ptrToBind, BIND_TYPE_POINTER, symbolName, 0, 0, libraryOrdinal, "lazy ", NULL);
++fgTotalLazyBindFixups;
return symbolAddr;
}
}
}
break;
}
cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
}
dyld::throwf("lazy pointer not found at address %p in image %s", lazyPointer, this->getPath());
}
uintptr_t ImageLoaderMachOCompressed::doBindFastLazySymbol(uint32_t lazyBindingInfoOffset, const LinkContext& context,
void (*lock)(), void (*unlock)())
{
if ( this->usesTwoLevelNameSpace() ) {
}
else {
if ( lock != NULL )
lock();
}
const uint8_t* const start = fLinkEditBase + fDyldInfo->lazy_bind_off;
const uint8_t* const end = &start[fDyldInfo->lazy_bind_size];
if ( lazyBindingInfoOffset > fDyldInfo->lazy_bind_size ) {
dyld::throwf("fast lazy bind offset out of range (%u, max=%u) in image %s",
lazyBindingInfoOffset, fDyldInfo->lazy_bind_size, this->getPath());
}
uint8_t type = BIND_TYPE_POINTER;
uintptr_t address = 0;
const char* symbolName = NULL;
uint8_t symboFlags = 0;
int libraryOrdinal = 0;
bool done = false;
uintptr_t result = 0;
const uint8_t* p = &start[lazyBindingInfoOffset];
while ( !done && (p < end) ) {
uint8_t immediate = *p & BIND_IMMEDIATE_MASK;
uint8_t opcode = *p & BIND_OPCODE_MASK;
++p;
switch (opcode) {
case BIND_OPCODE_DONE:
done = true;
break;
case BIND_OPCODE_SET_DYLIB_ORDINAL_IMM:
libraryOrdinal = immediate;
break;
case BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB:
libraryOrdinal = read_uleb128(p, end);
break;
case BIND_OPCODE_SET_DYLIB_SPECIAL_IMM:
if ( immediate == 0 )
libraryOrdinal = 0;
else {
int8_t signExtended = BIND_OPCODE_MASK | immediate;
libraryOrdinal = signExtended;
}
break;
case BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
symbolName = (char*)p;
symboFlags = immediate;
while (*p != '\0')
++p;
++p;
break;
case BIND_OPCODE_SET_TYPE_IMM:
type = immediate;
break;
case BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
if ( immediate > fSegmentsCount )
dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is too large (%d)\n",
immediate, fSegmentsCount);
address = segActualLoadAddress(immediate) + read_uleb128(p, end);
break;
case BIND_OPCODE_DO_BIND:
result = this->bindAt(context, address, type, symbolName, 0, 0, libraryOrdinal, "lazy ", NULL, true);
break;
case BIND_OPCODE_SET_ADDEND_SLEB:
case BIND_OPCODE_ADD_ADDR_ULEB:
case BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB:
case BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED:
case BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB:
default:
dyld::throwf("bad lazy bind opcode %d", *p);
}
}
if ( !this->usesTwoLevelNameSpace() ) {
if ( unlock != NULL )
unlock();
}
return result;
}
void ImageLoaderMachOCompressed::initializeCoalIterator(CoalIterator& it, unsigned int loadOrder)
{
it.image = this;
it.symbolName = " ";
it.loadOrder = loadOrder;
it.weakSymbol = false;
it.symbolMatches = false;
it.done = false;
it.curIndex = 0;
it.endIndex = this->fDyldInfo->weak_bind_size;
it.address = 0;
it.type = 0;
it.addend = 0;
}
bool ImageLoaderMachOCompressed::incrementCoalIterator(CoalIterator& it)
{
if ( it.done )
return false;
if ( this->fDyldInfo->weak_bind_size == 0 ) {
it.done = true;
it.symbolName = "~~~";
return true;
}
const uint8_t* start = fLinkEditBase + fDyldInfo->weak_bind_off;
const uint8_t* p = start + it.curIndex;
const uint8_t* end = fLinkEditBase + fDyldInfo->weak_bind_off + this->fDyldInfo->weak_bind_size;
uint32_t count;
uint32_t skip;
while ( p < end ) {
uint8_t immediate = *p & BIND_IMMEDIATE_MASK;
uint8_t opcode = *p & BIND_OPCODE_MASK;
++p;
switch (opcode) {
case BIND_OPCODE_DONE:
it.done = true;
it.curIndex = p - start;
it.symbolName = "~~~"; return true;
case BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
it.symbolName = (char*)p;
it.weakSymbol = ((immediate & BIND_SYMBOL_FLAGS_NON_WEAK_DEFINITION) == 0);
it.symbolMatches = false;
while (*p != '\0')
++p;
++p;
it.curIndex = p - start;
return false;
case BIND_OPCODE_SET_TYPE_IMM:
it.type = immediate;
break;
case BIND_OPCODE_SET_ADDEND_SLEB:
it.addend = read_sleb128(p, end);
break;
case BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
if ( immediate > fSegmentsCount )
dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is too large (%d)\n",
immediate, fSegmentsCount);
it.address = segActualLoadAddress(immediate) + read_uleb128(p, end);
break;
case BIND_OPCODE_ADD_ADDR_ULEB:
it.address += read_uleb128(p, end);
break;
case BIND_OPCODE_DO_BIND:
it.address += sizeof(intptr_t);
break;
case BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB:
it.address += read_uleb128(p, end) + sizeof(intptr_t);
break;
case BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED:
it.address += immediate*sizeof(intptr_t) + sizeof(intptr_t);
break;
case BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB:
count = read_uleb128(p, end);
skip = read_uleb128(p, end);
for (uint32_t i=0; i < count; ++i) {
it.address += skip + sizeof(intptr_t);
}
break;
default:
dyld::throwf("bad weak bind opcode %d", *p);
}
}
it.done = true;
it.symbolName = "~~~";
return true;
}
uintptr_t ImageLoaderMachOCompressed::getAddressCoalIterator(CoalIterator& it, const LinkContext& context)
{
const ImageLoader* foundIn = NULL;
const ImageLoader::Symbol* sym = this->findExportedSymbol(it.symbolName, &foundIn);
if ( sym != NULL ) {
return foundIn->getExportedSymbolAddress(sym, context, this);
}
return 0;
}
void ImageLoaderMachOCompressed::updateUsesCoalIterator(CoalIterator& it, uintptr_t value, ImageLoader* targetImage, const LinkContext& context)
{
if ( this->getState() < dyld_image_state_bound )
return;
const uint8_t* start = fLinkEditBase + fDyldInfo->weak_bind_off;
const uint8_t* p = start + it.curIndex;
const uint8_t* end = fLinkEditBase + fDyldInfo->weak_bind_off + this->fDyldInfo->weak_bind_size;
uint8_t type = it.type;
uintptr_t address = it.address;
const char* symbolName = it.symbolName;
intptr_t addend = it.addend;
uint32_t count;
uint32_t skip;
bool done = false;
bool boundSomething = false;
while ( !done && (p < end) ) {
uint8_t immediate = *p & BIND_IMMEDIATE_MASK;
uint8_t opcode = *p & BIND_OPCODE_MASK;
++p;
switch (opcode) {
case BIND_OPCODE_DONE:
done = true;
break;
case BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
done = true;
break;
case BIND_OPCODE_SET_TYPE_IMM:
type = immediate;
break;
case BIND_OPCODE_SET_ADDEND_SLEB:
addend = read_sleb128(p, end);
break;
case BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
if ( immediate > fSegmentsCount )
dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is too large (%d)\n",
immediate, fSegmentsCount);
address = segActualLoadAddress(immediate) + read_uleb128(p, end);
break;
case BIND_OPCODE_ADD_ADDR_ULEB:
address += read_uleb128(p, end);
break;
case BIND_OPCODE_DO_BIND:
bindLocation(context, address, value, targetImage, type, symbolName, addend, "weak ");
boundSomething = true;
address += sizeof(intptr_t);
break;
case BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB:
bindLocation(context, address, value, targetImage, type, symbolName, addend, "weak ");
boundSomething = true;
address += read_uleb128(p, end) + sizeof(intptr_t);
break;
case BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED:
bindLocation(context, address, value, targetImage, type, symbolName, addend, "weak ");
boundSomething = true;
address += immediate*sizeof(intptr_t) + sizeof(intptr_t);
break;
case BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB:
count = read_uleb128(p, end);
skip = read_uleb128(p, end);
for (uint32_t i=0; i < count; ++i) {
bindLocation(context, address, value, targetImage, type, symbolName, addend, "weak ");
boundSomething = true;
address += skip + sizeof(intptr_t);
}
break;
default:
dyld::throwf("bad bind opcode %d in weak binding info", *p);
}
}
if ( boundSomething && (targetImage != this) && !targetImage->neverUnload() )
this->addDynamicReference(targetImage);
}
uintptr_t ImageLoaderMachOCompressed::interposeAt(const LinkContext& context, uintptr_t addr, uint8_t type, const char*,
uint8_t, intptr_t, int, const char*, LastLookup*, bool runResolver)
{
if ( type == BIND_TYPE_POINTER ) {
uintptr_t* fixupLocation = (uintptr_t*)addr;
uintptr_t value = *fixupLocation;
for (std::vector<InterposeTuple>::iterator it=fgInterposingTuples.begin(); it != fgInterposingTuples.end(); it++) {
if ( (value == it->replacee) && (this != it->replacementImage) ) {
if ( context.verboseInterposing ) {
dyld::log("dyld: interposing: at %p replace 0x%lX with 0x%lX in %s\n",
fixupLocation, it->replacee, it->replacement, this->getPath());
}
*fixupLocation = it->replacement;
}
}
}
return 0;
}
void ImageLoaderMachOCompressed::doInterpose(const LinkContext& context)
{
if ( context.verboseInterposing )
dyld::log("dyld: interposing %lu tuples onto image: %s\n", fgInterposingTuples.size(), this->getPath());
eachBind(context, &ImageLoaderMachOCompressed::interposeAt);
eachLazyBind(context, &ImageLoaderMachOCompressed::interposeAt);
}
const char* ImageLoaderMachOCompressed::findClosestSymbol(const void* addr, const void** closestAddr) const
{
const macho_nlist* symbolTable = NULL;
const char* symbolTableStrings = NULL;
const dysymtab_command* dynSymbolTable = NULL;
const uint32_t cmd_count = ((macho_header*)fMachOData)->ncmds;
const struct load_command* const cmds = (struct load_command*)&fMachOData[sizeof(macho_header)];
const struct load_command* cmd = cmds;
for (uint32_t i = 0; i < cmd_count; ++i) {
switch (cmd->cmd) {
case LC_SYMTAB:
{
const struct symtab_command* symtab = (struct symtab_command*)cmd;
symbolTableStrings = (const char*)&fLinkEditBase[symtab->stroff];
symbolTable = (macho_nlist*)(&fLinkEditBase[symtab->symoff]);
}
break;
case LC_DYSYMTAB:
dynSymbolTable = (struct dysymtab_command*)cmd;
break;
}
cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
}
if ( (symbolTable == NULL) || (dynSymbolTable == NULL) )
return NULL;
uintptr_t targetAddress = (uintptr_t)addr - fSlide;
const struct macho_nlist* bestSymbol = NULL;
const struct macho_nlist* const globalsStart = &symbolTable[dynSymbolTable->iextdefsym];
const struct macho_nlist* const globalsEnd= &globalsStart[dynSymbolTable->nextdefsym];
for (const struct macho_nlist* s = globalsStart; s < globalsEnd; ++s) {
if ( (s->n_type & N_TYPE) == N_SECT ) {
if ( bestSymbol == NULL ) {
if ( s->n_value <= targetAddress )
bestSymbol = s;
}
else if ( (s->n_value <= targetAddress) && (bestSymbol->n_value < s->n_value) ) {
bestSymbol = s;
}
}
}
const struct macho_nlist* const localsStart = &symbolTable[dynSymbolTable->ilocalsym];
const struct macho_nlist* const localsEnd= &localsStart[dynSymbolTable->nlocalsym];
for (const struct macho_nlist* s = localsStart; s < localsEnd; ++s) {
if ( ((s->n_type & N_TYPE) == N_SECT) && ((s->n_type & N_STAB) == 0) ) {
if ( bestSymbol == NULL ) {
if ( s->n_value <= targetAddress )
bestSymbol = s;
}
else if ( (s->n_value <= targetAddress) && (bestSymbol->n_value < s->n_value) ) {
bestSymbol = s;
}
}
}
if ( bestSymbol != NULL ) {
#if __arm__
if (bestSymbol->n_desc & N_ARM_THUMB_DEF)
*closestAddr = (void*)((bestSymbol->n_value | 1) + fSlide);
else
*closestAddr = (void*)(bestSymbol->n_value + fSlide);
#else
*closestAddr = (void*)(bestSymbol->n_value + fSlide);
#endif
return &symbolTableStrings[bestSymbol->n_un.n_strx];
}
return NULL;
}
#if PREBOUND_IMAGE_SUPPORT
void ImageLoaderMachOCompressed::resetPreboundLazyPointers(const LinkContext& context)
{
}
#endif
#if __arm__ || __x86_64__
void ImageLoaderMachOCompressed::updateAlternateLazyPointer(uint8_t* stub, void** originalLazyPointerAddr)
{
#if __arm__
uint32_t* instructions = (uint32_t*)stub;
if ( (instructions[0] != 0xe59fc004) || (instructions[1] != 0xe08fc00c) || (instructions[2] != 0xe59cf000) )
return;
void** lazyPointerAddr = (void**)(instructions[3] + (stub + 12));
#endif
#if __x86_64__
if ( (stub[0] != 0xFF) || (stub[1] != 0x25) )
return;
int32_t ripOffset = *((int32_t*)(&stub[2]));
void** lazyPointerAddr = (void**)(ripOffset + stub + 6);
#endif
if ( lazyPointerAddr != originalLazyPointerAddr ) {
*lazyPointerAddr = *originalLazyPointerAddr;
}
}
#endif
void ImageLoaderMachOCompressed::updateOptimizedLazyPointers(const LinkContext& context)
{
#if __arm__ || __x86_64__
const struct macho_section* stubsSection = NULL;
const struct macho_section* lazyPointerSection = NULL;
const dysymtab_command* dynSymbolTable = NULL;
const macho_header* mh = (macho_header*)fMachOData;
const uint32_t cmd_count = mh->ncmds;
const struct load_command* const cmds = (struct load_command*)&fMachOData[sizeof(macho_header)];
const struct load_command* cmd = cmds;
for (uint32_t i = 0; i < cmd_count; ++i) {
if (cmd->cmd == LC_SEGMENT_COMMAND) {
const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
const struct macho_section* const sectionsStart = (struct macho_section*)((char*)seg + sizeof(struct macho_segment_command));
const struct macho_section* const sectionsEnd = §ionsStart[seg->nsects];
for (const struct macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
const uint8_t type = sect->flags & SECTION_TYPE;
if ( type == S_SYMBOL_STUBS )
stubsSection = sect;
else if ( type == S_LAZY_SYMBOL_POINTERS )
lazyPointerSection = sect;
}
}
else if ( cmd->cmd == LC_DYSYMTAB ) {
dynSymbolTable = (struct dysymtab_command*)cmd;
}
cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
}
if ( dynSymbolTable == NULL )
return;
if ( (stubsSection == NULL) || (lazyPointerSection == NULL) )
return;
const uint32_t stubsCount = stubsSection->size / stubsSection->reserved2;
const uint32_t lazyPointersCount = lazyPointerSection->size / sizeof(void*);
if ( stubsCount != lazyPointersCount )
return;
const uint32_t stubsIndirectTableOffset = stubsSection->reserved1;
const uint32_t lazyPointersIndirectTableOffset = lazyPointerSection->reserved1;
if ( (stubsIndirectTableOffset+stubsCount) > dynSymbolTable->nindirectsyms )
return;
if ( (lazyPointersIndirectTableOffset+lazyPointersCount) > dynSymbolTable->nindirectsyms )
return;
const uint32_t* const indirectTable = (uint32_t*)&fLinkEditBase[dynSymbolTable->indirectsymoff];
void** const lazyPointersStartAddr = (void**)(lazyPointerSection->addr + this->fSlide);
uint8_t* const stubsStartAddr = (uint8_t*)(stubsSection->addr + this->fSlide);
uint8_t* stub = stubsStartAddr;
void** lpa = lazyPointersStartAddr;
for(uint32_t i=0; i < stubsCount; ++i, stub += stubsSection->reserved2, ++lpa) {
if ( indirectTable[stubsIndirectTableOffset+i] != indirectTable[lazyPointersIndirectTableOffset+i] )
continue;
this->updateAlternateLazyPointer(stub, lpa);
}
#endif
}