Loading...
--- dyld/dyld-45.3/src/ImageLoaderMachO.cpp
+++ dyld/dyld-96.2/src/ImageLoaderMachO.cpp
@@ -1,6 +1,6 @@
/* -*- mode: C++; c-basic-offset: 4; tab-width: 4 -*-
*
- * Copyright (c) 2004-2005 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2004-2007 Apple Inc. All rights reserved.
*
* @APPLE_LICENSE_HEADER_START@
*
@@ -22,9 +22,16 @@
* @APPLE_LICENSE_HEADER_END@
*/
+// work around until conformance work is complete rdar://problem/4508801
+#define __srr0 srr0
+#define __eip eip
+#define __rip rip
+
+
#include <string.h>
#include <fcntl.h>
#include <sys/types.h>
+#include <sys/fcntl.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <mach/shared_memory_server.h>
@@ -34,19 +41,29 @@
#include <mach-o/reloc.h>
#include <mach-o/nlist.h>
#include <sys/sysctl.h>
+#include <libkern/OSAtomic.h>
+#include <libkern/OSCacheControl.h>
#if __ppc__ || __ppc64__
#include <mach-o/ppc/reloc.h>
#endif
+#if __x86_64__
+ #include <mach-o/x86_64/reloc.h>
+#endif
+
+#ifndef MH_PIE
+ #define MH_PIE 0x200000
+#endif
+
+#ifndef S_DTRACE_DOF
+ #define S_DTRACE_DOF 0xF
+#endif
#ifndef S_ATTR_SELF_MODIFYING_CODE
#define S_ATTR_SELF_MODIFYING_CODE 0x04000000
#endif
#include "ImageLoaderMachO.h"
-#include "mach-o/dyld_gdb.h"
-
-// no header for this yet, rdar://problem/3850825
-extern "C" void sys_icache_invalidate(void *, size_t);
+#include "mach-o/dyld_images.h"
// optimize strcmp for ppc
#if __ppc__
@@ -54,6 +71,11 @@
#else
#define astrcmp(a,b) strcmp(a,b)
#endif
+
+// in libc.a
+extern "C" void _spin_lock(uint32_t*);
+extern "C" void _spin_unlock(uint32_t*);
+
// relocation_info.r_length field has value 3 for 64-bit executables and value 2 for 32-bit executables
#if __LP64__
@@ -76,12 +98,19 @@
struct macho_routines_command : public routines_command {};
#endif
+#if __x86_64__
+ #define POINTER_RELOC X86_64_RELOC_UNSIGNED
+#else
#define POINTER_RELOC GENERIC_RELOC_VANILLA
+#endif
uint32_t ImageLoaderMachO::fgHintedBinaryTreeSearchs = 0;
uint32_t ImageLoaderMachO::fgUnhintedBinaryTreeSearchs = 0;
uint32_t ImageLoaderMachO::fgCountOfImagesWithWeakExports = 0;
+#if __i386__
+uint32_t ImageLoaderMachO::fgReadOnlyImportSpinLock = 0;
+#endif
//#define LINKEDIT_USAGE_DEBUG 1
@@ -96,8 +125,11 @@
static void noteAccessedLinkEditAddress(const void* addr)
{
uintptr_t page = ((uintptr_t)addr) & (-4096);
+ if ( sLinkEditPageBuckets.count(page) == 0 ) {
+ ImageLoader* inImage = dyld::findImageContainingAddress(addr);
+ dyld::log("dyld: accessing page 0x%016lX in __LINKEDIT of %s\n", page, inImage != NULL ? inImage->getPath() : "unknown" );
+ }
sLinkEditPageBuckets.insert(page);
- fprintf(stderr, "dyld: accessing page 0x%08lX in __LINKEDIT of %s\n", page, dyld::findImageContainingAddress(addr)->getPath());
}
#endif
@@ -110,19 +142,78 @@
fStrings = NULL;
fDynamicInfo = NULL;
fSlide = 0;
+ fTwoLevelHints = NULL;
+ fDylibID = NULL;
+#if TEXT_RELOC_SUPPORT
+ fTextSegmentWithFixups = NULL;
+#endif
+#if __i386__
+ fReadOnlyImportSegment = NULL;
+#endif
fIsSplitSeg = false;
+ fInSharedCache = false;
+#if __ppc64__
+ f4GBWritable = false;
+#endif
fHasSubLibraries= false;
fHasSubUmbrella = false;
- fDashInit = NULL;
- fModInitSection = NULL;
- fModTermSection = NULL;
- fDATAdyld = NULL;
- fImageNotifySection = NULL;
- fTwoLevelHints = NULL;
- fDylibID = NULL;
- fReExportThruFramework = NULL;
- fTextSegmentWithFixups = NULL;
-}
+ fInUmbrella = false;
+ fHasDOFSections = false;
+ fHasDashInit = false;
+ fHasInitializers= false;
+ fHasTerminators = false;
+#if IMAGE_NOTIFY_SUPPORT
+ fHasImageNotifySection = false;
+#endif
+}
+
+// create image for main executable
+ImageLoaderMachO::ImageLoaderMachO(const struct mach_header* mh, uintptr_t slide, const char* path, const LinkContext& context)
+ : ImageLoader(path)
+{
+ // clean slate
+ this->init();
+
+ // temporary use this buffer until TEXT is mapped in
+ fMachOData = (const uint8_t*)mh;
+
+ // create segments
+ this->instantiateSegments((const uint8_t*)mh);
+
+ // set slide for PIE programs
+ this->setSlide(slide);
+
+ // get pointers to interesting things
+ this->parseLoadCmds();
+
+ // update segments to reference load commands in mapped in __TEXT segment
+ this->adjustSegments();
+
+#if __i386__
+ // kernel may have mapped in __IMPORT segment read-only, we need it read/write to do binding
+ if ( fReadOnlyImportSegment != NULL )
+ fReadOnlyImportSegment->tempWritable(context, this);
+#endif
+
+ // for PIE record end of program, to know where to start loading dylibs
+ if ( mh->flags & MH_PIE )
+ Segment::fgNextPIEDylibAddress = (uintptr_t)this->getEnd();
+
+ // notify state change
+ this->setMapped(context);
+
+ if ( context.verboseMapping ) {
+ dyld::log("dyld: Main executable mapped %s\n", this->getPath());
+ for (ImageLoader::SegmentIterator it = this->beginSegments(); it != this->endSegments(); ++it ) {
+ Segment* seg = *it;
+ if ( (strcmp(seg->getName(), "__PAGEZERO") == 0) || (strcmp(seg->getName(), "__UNIXSTACK") == 0) )
+ dyld::log("%18s at 0x%08lX->0x%08lX\n", seg->getName(), seg->getPreferredLoadAddress(), seg->getPreferredLoadAddress()+seg->getSize());
+ else
+ dyld::log("%18s at 0x%08lX->0x%08lX\n", seg->getName(), seg->getActualLoadAddress(this), seg->getActualLoadAddress(this)+seg->getSize());
+ }
+ }
+}
+
// create image by copying an in-memory mach-o file
ImageLoaderMachO::ImageLoaderMachO(const char* moduleName, const struct mach_header* mh, uint64_t len, const LinkContext& context)
@@ -137,12 +228,68 @@
// create segments
this->instantiateSegments((const uint8_t*)mh);
- // map segments
- if ( mh->filetype != MH_EXECUTE )
+ // map segments
+ if ( mh->filetype == MH_EXECUTE ) {
+ throw "can't load another MH_EXECUTE";
+ }
+ else {
ImageLoader::mapSegments((const void*)mh, len, context);
-
+ }
+
+ // for compatibility, never unload dylibs loaded from memory
+ this->setNeverUnload();
+
// get pointers to interesting things
this->parseLoadCmds();
+
+ // update segments to reference load commands in mapped in __TEXT segment
+ this->adjustSegments();
+
+ // bundle loads need path copied
+ if ( moduleName != NULL )
+ this->setPath(moduleName);
+
+ // notify state change
+ this->setMapped(context);
+
+}
+
+// create image by using cached mach-o file
+ImageLoaderMachO::ImageLoaderMachO(const struct mach_header* mh, const char* path, const struct stat& info, const LinkContext& context)
+ : ImageLoader(path, 0, info)
+{
+ // clean slate
+ this->init();
+
+ // already mapped to mh address
+ fMachOData = (const uint8_t*)mh;
+
+ // usually a split seg
+ fIsSplitSeg = ((mh->flags & MH_SPLIT_SEGS) != 0);
+
+ // remember this is from shared cache and cannot be unloaded
+ fInSharedCache = true;
+ this->setNeverUnload();
+
+ // create segments
+ this->instantiateSegments((const uint8_t*)mh);
+
+ // segments already mapped in cache
+ if ( context.verboseMapping ) {
+ dyld::log("dyld: Using shared cached for %s\n", path);
+ for (ImageLoader::SegmentIterator it = this->beginSegments(); it != this->endSegments(); ++it ) {
+ Segment* seg = *it;
+ dyld::log("%18s at 0x%08lX->0x%08lX\n", seg->getName(), seg->getActualLoadAddress(this), seg->getActualLoadAddress(this)+seg->getSize());
+ }
+ }
+
+ // get pointers to interesting things
+ this->parseLoadCmds();
+
+ // note: path is mapped into cache so no need for ImageLoader to make a copy
+
+ // notify state change
+ this->setMapped(context);
}
@@ -177,16 +324,62 @@
// map segments, except for main executable which is already mapped in by kernel
if ( ((macho_header*)fileData)->filetype != MH_EXECUTE )
this->mapSegments(fd, offsetInFat, lenInFat, info.st_size, context);
-
+
// get pointers to interesting things
this->parseLoadCmds();
-}
+
+ // update segments to reference load commands in mapped in __TEXT segment
+ this->adjustSegments();
+
+ // notify state change
+ this->setMapped(context);
+
+ // if path happens to be same as in LC_DYLIB_ID load command use that, otherwise malloc a copy of the path
+ const char* installName = getInstallPath();
+ if ( (installName != NULL) && (strcmp(installName, path) == 0) && (path[0] == '/') )
+ this->setPathUnowned(installName);
+ if ( path[0] != '/' ) {
+ // rdar://problem/5135363 turn relative paths into absolute paths so gdb, Symbolication can later find them
+ char realPath[MAXPATHLEN];
+ if ( realpath(path, realPath) != NULL )
+ this->setPath(realPath);
+ else
+ this->setPath(path);
+ }
+ else
+ this->setPath(path);
+
+ // tell kernel about pages we are going to need soon
+ if ( ! context.preFetchDisabled )
+ this->preFetch(fd, offsetInFat, context);
+
+}
+
+
ImageLoaderMachO::~ImageLoaderMachO()
{
// keep count of images with weak exports
if ( this->hasCoalescedExports() )
--fgCountOfImagesWithWeakExports;
+
+ // keep count of images used in shared cache
+ if ( fInSharedCache )
+ --fgImagesUsedFromSharedCache;
+
+ // usually unmap image when done
+ if ( ! this->leaveMapped() && (this->getState() >= dyld_image_state_mapped) ) {
+ // first segment has load commands, so unmap last
+ Segment* firstSeg = *(this->beginSegments());
+ for(ImageLoader::SegmentIterator it = this->beginSegments(); it != this->endSegments(); ++it ) {
+ Segment* seg = *it;
+ if ( seg != firstSeg )
+ seg->unmap(this);
+ }
+ firstSeg->unmap(this);
+ }
+ // free segment objects
+ free(fSegmentsArray);
}
@@ -196,18 +389,114 @@
const uint32_t cmd_count = ((macho_header*)fileData)->ncmds;
const struct load_command* const cmds = (struct load_command*)&fileData[sizeof(macho_header)];
- // construct Segment object for each LC_SEGMENT cmd and add to list
+ // count LC_SEGMENT cmd and reserve that many segment slots
+ uint32_t segCount = 0;
const struct load_command* cmd = cmds;
for (unsigned long i = 0; i < cmd_count; ++i) {
if ( cmd->cmd == LC_SEGMENT_COMMAND ) {
- if ( (((struct macho_segment_command*)cmd)->vmsize != 0) || !fIsSplitSeg )
- fSegments.push_back(new SegmentMachO((struct macho_segment_command*)cmd, this, fileData));
+ // ignore zero-sized segments
+ if ( ((struct macho_segment_command*)cmd)->vmsize != 0 )
+ ++segCount;
}
cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
}
-}
-
-
+ // fSegmentsArrayCount is only 8-bits
+ if ( segCount > 255 )
+ dyld::throwf("more than 255 segments in %s", this->getPath());
+
+ // allocate array of segment objects in one call to malloc()
+ //fSegmentsArray = static_cast<SegmentMachO*>(operator new[](segCount*sizeof(SegmentMachO)));
+ fSegmentsArray = static_cast<SegmentMachO*>(malloc(segCount*sizeof(SegmentMachO)));
+ fSegmentsArrayCount = segCount;
+
+ // construct Segment object for each LC_SEGMENT cmd using "placment new"
+ uint32_t segIndex = 0;
+ cmd = cmds;
+ for (unsigned long i = 0; i < cmd_count; ++i) {
+ if ( cmd->cmd == LC_SEGMENT_COMMAND ) {
+ const struct macho_segment_command* segCmd = (struct macho_segment_command*)cmd;
+ // ignore zero-sized segments
+ if ( segCmd->vmsize != 0 )
+ new (&fSegmentsArray[segIndex++]) SegmentMachO(segCmd);
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+}
+
+
+void ImageLoaderMachO::adjustSegments()
+{
+ // tell each segment where is load command is finally mapped
+ const uint32_t cmd_count = ((macho_header*)fMachOData)->ncmds;
+ const struct load_command* const cmds = (struct load_command*)&fMachOData[sizeof(macho_header)];
+ uint32_t segIndex = 0;
+ const struct load_command* cmd = cmds;
+ for (unsigned long i = 0; i < cmd_count; ++i) {
+ if ( cmd->cmd == LC_SEGMENT_COMMAND ) {
+ const struct macho_segment_command* segCmd = (struct macho_segment_command*)cmd;
+ // ignore zero-sized segments
+ if ( segCmd->vmsize != 0 ) {
+ fSegmentsArray[segIndex].adjust(segCmd);
+ ++segIndex;
+ }
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+}
+
+void ImageLoaderMachO::preFetch(int fd, uint64_t offsetInFat, const LinkContext& context)
+{
+ // always prefetch a subrange of __LINKEDIT pages
+ uintptr_t symbolTableOffset = (uintptr_t)fSymbolTable - (uintptr_t)fLinkEditBase;
+ uintptr_t stringTableOffset = (uintptr_t)fStrings - (uintptr_t)fLinkEditBase;
+ uintptr_t start;
+ // if image did not load at preferred address
+ if ( fSegmentsArray[0].getPreferredLoadAddress() != (uintptr_t)fMachOData ) {
+ // local relocations will be processed, so start pre-fetch at local symbols
+ start = offsetInFat + fDynamicInfo->locreloff;
+ }
+ else {
+ // otherwise start pre-fetch at global symbols section of symbol table
+ start = offsetInFat + symbolTableOffset + fDynamicInfo->iextdefsym * sizeof(macho_nlist);
+ }
+ // prefetch ends at end of last undefined string in string pool
+ uintptr_t end = offsetInFat + stringTableOffset;
+ if ( fDynamicInfo->nundefsym != 0 )
+ end += fSymbolTable[fDynamicInfo->iundefsym+fDynamicInfo->nundefsym-1].n_un.n_strx;
+ else if ( fDynamicInfo->nextdefsym != 0 )
+ end += fSymbolTable[fDynamicInfo->iextdefsym+fDynamicInfo->nextdefsym-1].n_un.n_strx;
+
+ radvisory advice;
+ advice.ra_offset = start & (-4096); // page align
+ advice.ra_count = (end-advice.ra_offset+4095) & (-4096);
+ fgTotalBytesPreFetched += advice.ra_count;
+ fcntl(fd, F_RDADVISE, &advice);
+ if ( context.verboseMapping ) {
+ dyld::log("%18s prefetching 0x%0llX -> 0x%0llX\n",
+ "__LINKEDIT", advice.ra_offset+(uintptr_t)fLinkEditBase-offsetInFat, advice.ra_offset+advice.ra_count+(uintptr_t)fLinkEditBase-offsetInFat);
+ }
+
+ // prefetch __DATA/__OBJC pages during launch, but not for dynamically loaded code
+ if ( context.linkingMainExecutable ) {
+ for (ImageLoader::SegmentIterator it = this->beginSegments(); it != this->endSegments(); ++it ) {
+ Segment* seg = *it;
+ if ( seg->writeable() && (seg->getFileSize() > 0) ) {
+ // prefetch writable segment that have mmap'ed regions
+ advice.ra_offset = offsetInFat + seg->getFileOffset();
+ advice.ra_count = seg->getFileSize();
+ // limit prefetch to 1MB (256 pages)
+ if ( advice.ra_count > 1024*1024 )
+ advice.ra_count = 1024*1024;
+ fgTotalBytesPreFetched += advice.ra_count;
+ fcntl(fd, F_RDADVISE, &advice);
+ if ( context.verboseMapping ) {
+ dyld::log("%18s prefetching 0x%0lX -> 0x%0lX\n",
+ seg->getName(), seg->getActualLoadAddress(this), seg->getActualLoadAddress(this)+advice.ra_count-1);
+ }
+ }
+ }
+ }
+}
bool ImageLoaderMachO::segmentsMustSlideTogether() const
{
@@ -262,9 +551,12 @@
return ( (mh->flags & MH_BINDS_TO_WEAK) != 0 );
}
-#if !__LP64__ // split segs not supported for 64-bits
-
-#if 1 // hack until kernel headers and glue are in system
+
+
+
+
+
+// hack until kernel headers and glue are in system
struct _shared_region_mapping_np {
mach_vm_address_t address;
mach_vm_size_t size;
@@ -277,6 +569,7 @@
mach_vm_size_t size;
};
+#if SPLIT_SEG_SHARED_REGION_SUPPORT
// Called by dyld.
// Requests the kernel to map a number of regions from the fd into the
// shared sections address range (0x90000000-0xAFFFFFFF).
@@ -296,13 +589,13 @@
const _shared_region_mapping_np regions[], // the array of regions to map
uint64_t* slide) // the amount all regions were slid, NULL means don't attempt to slide
{
- //fprintf(stderr, "%s(%i, %u, %8p, %8p)\n", __func__, fd, regionCount, regions, slide);
+ //dyld::log("%s(%i, %u, %8p, %8p)\n", __func__, fd, regionCount, regions, slide);
//for ( unsigned int i=0; i < regionCount; ++i) {
- // fprintf(stderr, "\taddress=0x%08llX, size=0x%08llX\n", regions[i].address, regions[i].size);
+ // dyld::log("\taddress=0x%08llX, size=0x%08llX\n", regions[i].address, regions[i].size);
//}
int r = syscall(299, fd, regionCount, regions, slide);
// if(0 != r)
-// fprintf(stderr, "%s(%i, %u, %8p, %8p) errno=%i (%s)\n", __func__, fd, regionCount, regions, slide, errno, strerror(errno));
+// dyld::log("%s(%i, %u, %8p, %8p) errno=%i (%s)\n", __func__, fd, regionCount, regions, slide, errno, strerror(errno));
return r;
}
// Called by dyld if shared_region_map_file() fails.
@@ -313,21 +606,14 @@
unsigned int rangeCount, // number of entres in array of msrp_range
const _shared_region_range_np ranges[]) // the array of shared regions to make private
{
- //fprintf(stderr, "%s(%u, %8p)\n", __func__, rangeCount, ranges);
+ //dyld::log("%s(%u, %8p)\n", __func__, rangeCount, ranges);
int r = syscall(300, rangeCount, ranges);
// if(0 != r)
-// fprintf(stderr, "%s(%u, %8p) errno=%i (%s)\n", __func__, rangeCount, ranges, errno, strerror(errno));
+// dyld::log("%s(%u, %8p) errno=%i (%s)\n", __func__, rangeCount, ranges, errno, strerror(errno));
return r;
}
#define KERN_SHREG_PRIVATIZABLE 54
-#endif // hack until kernel headers and glue are in system
-
-static uintptr_t sNextAltLoadAddress
-#if __ppc_
- = 0xC0000000;
-#else
- = 0;
-#endif
+
static int
_shared_region_map_file_with_mmap(
@@ -351,8 +637,8 @@
if ( regions[i].init_prot & VM_PROT_WRITE )
protection |= PROT_WRITE;
off_t offset = regions[i].file_offset;
- //fprintf(stderr, "mmap(%p, 0x%08lX, block=0x%08X, %s\n", mmapAddress, size, biggestDiff, fPath);
- mmapAddress = mmap(mmapAddress, size, protection, MAP_FILE | MAP_FIXED | MAP_PRIVATE, fd, offset);
+ //dyld::log("mmap(%p, 0x%08lX, block=0x%08X, %s\n", mmapAddress, size, biggestDiff, fPath);
+ mmapAddress = mmap(mmapAddress, size, protection, MAP_FIXED | MAP_PRIVATE, fd, offset);
if ( mmapAddress == ((void*)(-1)) )
throw "mmap error";
}
@@ -378,6 +664,56 @@
}
return 0 != value;
+}
+
+#endif // SPLIT_SEG_SHARED_REGION_SUPPORT
+
+
+#if SPLIT_SEG_DYLIB_SUPPORT
+unsigned int
+ImageLoaderMachO::getExtraZeroFillEntriesCount()
+{
+ // calculate mapping entries
+ unsigned int extraZeroFillEntries = 0;
+ for(ImageLoader::SegmentIterator it = this->beginSegments(); it != this->endSegments(); ++it ) {
+ Segment* seg = *it;
+ if ( seg->hasTrailingZeroFill() )
+ ++extraZeroFillEntries;
+ }
+
+ return extraZeroFillEntries;
+}
+
+void
+ImageLoaderMachO::initMappingTable(uint64_t offsetInFat,
+ _shared_region_mapping_np *mappingTable)
+{
+ unsigned int segmentCount = fSegmentsArrayCount;
+ for(unsigned int segIndex=0,entryIndex=0; segIndex < segmentCount; ++segIndex, ++entryIndex){
+ Segment* seg = &fSegmentsArray[segIndex];
+ _shared_region_mapping_np* entry = &mappingTable[entryIndex];
+ entry->address = seg->getActualLoadAddress(this);
+ entry->size = seg->getFileSize();
+ entry->file_offset = seg->getFileOffset() + offsetInFat;
+ entry->init_prot = VM_PROT_NONE;
+ if ( !seg->unaccessible() ) {
+ if ( seg->executable() )
+ entry->init_prot |= VM_PROT_EXECUTE;
+ if ( seg->readable() )
+ entry->init_prot |= VM_PROT_READ;
+ if ( seg->writeable() )
+ entry->init_prot |= VM_PROT_WRITE | VM_PROT_COW;
+ }
+ entry->max_prot = entry->init_prot;
+ if ( seg->hasTrailingZeroFill() ) {
+ _shared_region_mapping_np* zfentry = &mappingTable[++entryIndex];
+ zfentry->address = entry->address + seg->getFileSize();
+ zfentry->size = seg->getSize() - seg->getFileSize();
+ zfentry->file_offset = 0;
+ zfentry->init_prot = entry->init_prot | VM_PROT_COW | VM_PROT_ZF;
+ zfentry->max_prot = zfentry->init_prot;
+ }
+ }
}
int
@@ -387,7 +723,14 @@
uint64_t fileLen,
const LinkContext& context)
{
- const unsigned int segmentCount = fSegments.size();
+ static uintptr_t sNextAltLoadAddress
+ #if __ppc_
+ = 0xC0000000;
+ #else
+ = 0;
+ #endif
+
+ const unsigned int segmentCount = fSegmentsArrayCount;
const unsigned int extraZeroFillEntries = getExtraZeroFillEntriesCount();
const unsigned int regionCount = segmentCount+extraZeroFillEntries;
_shared_region_mapping_np regions[regionCount];
@@ -427,8 +770,8 @@
uintptr_t slide = sNextAltLoadAddress - regions[0].address;
this->setSlide(slide);
for(unsigned int i=0; i < regionCount; ++i) {
- if ( (regions[i].init_prot & VM_PROT_ZF) != 0 ) {
- // do nothing vm_allocate() zero-fills by default
+ if ( ((regions[i].init_prot & VM_PROT_ZF) != 0) || (regions[i].size == 0) ) {
+ // nothing to mmap for zero-fills areas, they are just vm_allocated
}
else {
void* mmapAddress = (void*)(uintptr_t)(regions[i].address + slide);
@@ -441,8 +784,8 @@
if ( regions[i].init_prot & VM_PROT_WRITE )
protection |= PROT_WRITE;
off_t offset = regions[i].file_offset;
- //fprintf(stderr, "mmap(%p, 0x%08lX, block=0x%08X, %s\n", mmapAddress, size, biggestDiff, fPath);
- mmapAddress = mmap(mmapAddress, size, protection, MAP_FILE | MAP_FIXED | MAP_PRIVATE, fd, offset);
+ //dyld::log("mmap(%p, 0x%08lX, block=0x%08X, %s\n", mmapAddress, size, biggestDiff, fPath);
+ mmapAddress = mmap(mmapAddress, size, protection, MAP_FIXED | MAP_PRIVATE, fd, offset);
if ( mmapAddress == ((void*)(-1)) )
throw "mmap error";
}
@@ -453,19 +796,19 @@
// logging
if ( context.verboseMapping ) {
- fprintf(stderr, "dyld: Mapping split-seg outside shared region, slid by 0x%08lX %s\n", this->fSlide, this->getPath());
+ dyld::log("dyld: Mapping split-seg outside shared region, slid by 0x%08lX %s\n", this->fSlide, this->getPath());
for(unsigned int segIndex=0,entryIndex=0; segIndex < segmentCount; ++segIndex, ++entryIndex){
- Segment* seg = fSegments[segIndex];
+ Segment* seg = &fSegmentsArray[segIndex];
const _shared_region_mapping_np* entry = ®ions[entryIndex];
if ( (entry->init_prot & VM_PROT_ZF) == 0 )
- fprintf(stderr, "%18s at 0x%08lX->0x%08lX\n",
- seg->getName(), seg->getActualLoadAddress(), seg->getActualLoadAddress()+seg->getFileSize()-1);
+ dyld::log("%18s at 0x%08lX->0x%08lX\n",
+ seg->getName(), seg->getActualLoadAddress(this), seg->getActualLoadAddress(this)+seg->getFileSize()-1);
if ( entryIndex < (regionCount-1) ) {
const _shared_region_mapping_np* nextEntry = ®ions[entryIndex+1];
if ( (nextEntry->init_prot & VM_PROT_ZF) != 0 ) {
uint64_t segOffset = nextEntry->address - entry->address;
- fprintf(stderr, "%18s at 0x%08lX->0x%08lX (zerofill)\n",
- seg->getName(), (uintptr_t)(seg->getActualLoadAddress() + segOffset), (uintptr_t)(seg->getActualLoadAddress() + segOffset + nextEntry->size - 1));
+ dyld::log("%18s at 0x%08lX->0x%08lX (zerofill)\n",
+ seg->getName(), (uintptr_t)(seg->getActualLoadAddress(this) + segOffset), (uintptr_t)(seg->getActualLoadAddress(this) + segOffset + nextEntry->size - 1));
++entryIndex;
}
}
@@ -478,10 +821,14 @@
void ImageLoaderMachO::mapSegments(int fd, uint64_t offsetInFat, uint64_t lenInFat, uint64_t fileLen, const LinkContext& context)
{
+ // non-split segment libraries handled by super class
+ if ( !fIsSplitSeg )
+ return ImageLoader::mapSegments(fd, offsetInFat, lenInFat, fileLen, context);
+
+#if SPLIT_SEG_SHARED_REGION_SUPPORT
enum SharedRegionState
{
kSharedRegionStartState = 0,
- kSharedRegionLoadFileState,
kSharedRegionMapFileState,
kSharedRegionMapFilePrivateState,
kSharedRegionMapFilePrivateMMapState,
@@ -489,42 +836,27 @@
};
static SharedRegionState sSharedRegionState = kSharedRegionStartState;
- // non-split segment libraries handled by super class
- if ( !fIsSplitSeg )
- return ImageLoader::mapSegments(fd, offsetInFat, lenInFat, fileLen, context);
-
if ( kSharedRegionStartState == sSharedRegionState ) {
if ( hasSharedRegionMapFile() ) {
- if ( context.slideAndPackDylibs ) {
- sharedRegionMakePrivate(context);
- // remove underlying submap and block out 0x90000000 to 0xAFFFFFFF
- vm_address_t addr = (vm_address_t)0x90000000;
- vm_deallocate(mach_task_self(), addr, 0x20000000);
- vm_allocate(mach_task_self(), &addr, 0x20000000, false);
- sSharedRegionState = kSharedRegionMapFilePrivateMMapState;
- }
- else if ( context.sharedRegionMode == kUsePrivateSharedRegion ) {
+ if ( context.sharedRegionMode == kUsePrivateSharedRegion ) {
sharedRegionMakePrivate(context);
sSharedRegionState = kSharedRegionMapFilePrivateState;
}
else if ( context.sharedRegionMode == kDontUseSharedRegion ) {
sSharedRegionState = kSharedRegionMapFilePrivateOutsideState;
}
+ else if ( context.sharedRegionMode == kSharedRegionIsSharedCache ) {
+ sSharedRegionState = kSharedRegionMapFilePrivateOutsideState;
+ }
else {
sSharedRegionState = kSharedRegionMapFileState;
}
}
else {
- sSharedRegionState = kSharedRegionLoadFileState;
- }
- }
-
- if ( kSharedRegionLoadFileState == sSharedRegionState ) {
- if ( 0 != sharedRegionLoadFile(fd, offsetInFat, lenInFat, fileLen, context) ) {
sSharedRegionState = kSharedRegionMapFilePrivateOutsideState;
}
}
- else
+
if ( kSharedRegionMapFileState == sSharedRegionState ) {
if ( 0 != sharedRegionMapFile(fd, offsetInFat, lenInFat, fileLen, context) ) {
sharedRegionMakePrivate(context);
@@ -543,77 +875,37 @@
throw "mapping error";
}
}
-}
-
-unsigned int
-ImageLoaderMachO::getExtraZeroFillEntriesCount()
-{
- // calculate mapping entries
- const unsigned int segmentCount = fSegments.size();
- unsigned int extraZeroFillEntries = 0;
- for(unsigned int i=0; i < segmentCount; ++i){
- Segment* seg = fSegments[i];
- if ( seg->hasTrailingZeroFill() )
- ++extraZeroFillEntries;
- }
-
- return extraZeroFillEntries;
-}
-
-void
-ImageLoaderMachO::initMappingTable(uint64_t offsetInFat,
- _shared_region_mapping_np *mappingTable)
-{
- unsigned int segmentCount = fSegments.size();
- for(unsigned int segIndex=0,entryIndex=0; segIndex < segmentCount; ++segIndex, ++entryIndex){
- Segment* seg = fSegments[segIndex];
- _shared_region_mapping_np* entry = &mappingTable[entryIndex];
- entry->address = seg->getActualLoadAddress();
- entry->size = seg->getFileSize();
- entry->file_offset = seg->getFileOffset() + offsetInFat;
- entry->init_prot = VM_PROT_NONE;
- if ( !seg->unaccessible() ) {
- if ( seg->executable() )
- entry->init_prot |= VM_PROT_EXECUTE;
- if ( seg->readable() )
- entry->init_prot |= VM_PROT_READ;
- if ( seg->writeable() )
- entry->init_prot |= VM_PROT_WRITE | VM_PROT_COW;
- }
- entry->max_prot = entry->init_prot;
- if ( seg->hasTrailingZeroFill() ) {
- _shared_region_mapping_np* zfentry = &mappingTable[++entryIndex];
- zfentry->address = entry->address + seg->getFileSize();
- zfentry->size = seg->getSize() - seg->getFileSize();
- zfentry->file_offset = 0;
- zfentry->init_prot = entry->init_prot | VM_PROT_COW | VM_PROT_ZF;
- zfentry->max_prot = zfentry->init_prot;
- }
- }
-}
-
-int
-ImageLoaderMachO::sharedRegionMakePrivate(const LinkContext& context)
+#else
+ // support old split-seg dylibs by mapping them where ever we find space
+ if ( sharedRegionMapFilePrivateOutside(fd, offsetInFat, lenInFat, fileLen, context) != 0 ) {
+ throw "mapping error";
+ }
+#endif
+}
+#endif // SPLIT_SEG_DYLIB_SUPPORT
+
+
+#if SPLIT_SEG_SHARED_REGION_SUPPORT
+int ImageLoaderMachO::sharedRegionMakePrivate(const LinkContext& context)
{
if ( context.verboseMapping )
- fprintf(stderr, "dyld: making shared regions private\n");
+ dyld::log("dyld: making shared regions private\n");
// shared mapping failed, so make private copy of shared region and try mapping private
- RegionsVector allRegions;
- context.getAllMappedRegions(allRegions);
- std::vector<_shared_region_range_np> splitSegRegions;
- const unsigned int allRegiontCount = allRegions.size();
- for(unsigned int i=0; i < allRegiontCount; ++i){
- MappedRegion region = allRegions[i];
- uint8_t highByte = region.address >> 28;
+ MappedRegion allRegions[context.imageCount()*8]; // assume average of less that eight segments per image
+ MappedRegion* end = context.getAllMappedRegions(allRegions);
+ _shared_region_range_np splitSegRegions[end-allRegions];
+ _shared_region_range_np* sp = splitSegRegions;
+ for (MappedRegion* p=allRegions; p < end; ++p) {
+ uint8_t highByte = p->address >> 28;
if ( (highByte == 9) || (highByte == 0xA) ) {
_shared_region_range_np splitRegion;
- splitRegion.address = region.address;
- splitRegion.size = region.size;
- splitSegRegions.push_back(splitRegion);
- }
- }
- int result = _shared_region_make_private_np(splitSegRegions.size(), &splitSegRegions[0]);
+ splitRegion.address = p->address;
+ splitRegion.size = p->size;
+ *sp++ = splitRegion;
+ }
+ }
+ int result = _shared_region_make_private_np(sp-splitSegRegions, splitSegRegions);
// notify gdb or other lurkers that this process is no longer using the shared region
dyld_all_image_infos.processDetachedFromSharedRegion = true;
return result;
@@ -627,7 +919,7 @@
const LinkContext& context)
{
// build table of segments to map
- const unsigned int segmentCount = fSegments.size();
+ const unsigned int segmentCount = fSegmentsArrayCount;
const unsigned int extraZeroFillEntries = getExtraZeroFillEntriesCount();
const unsigned int mappingTableCount = segmentCount+extraZeroFillEntries;
_shared_region_mapping_np mappingTable[mappingTableCount];
@@ -641,20 +933,21 @@
if(NULL != slidep && 0 != *slidep) {
// update with actual load addresses
}
+ this->setNeverUnload();
if ( context.verboseMapping ) {
- fprintf(stderr, "dyld: Mapping split-seg shared %s\n", this->getPath());
+ dyld::log("dyld: Mapping split-seg shared %s\n", this->getPath());
for(unsigned int segIndex=0,entryIndex=0; segIndex < segmentCount; ++segIndex, ++entryIndex){
- Segment* seg = fSegments[segIndex];
+ Segment* seg = &fSegmentsArray[segIndex];
const _shared_region_mapping_np* entry = &mappingTable[entryIndex];
if ( (entry->init_prot & VM_PROT_ZF) == 0 )
- fprintf(stderr, "%18s at 0x%08lX->0x%08lX\n",
- seg->getName(), seg->getActualLoadAddress(), seg->getActualLoadAddress()+seg->getFileSize()-1);
+ dyld::log("%18s at 0x%08lX->0x%08lX\n",
+ seg->getName(), seg->getActualLoadAddress(this), seg->getActualLoadAddress(this)+seg->getFileSize()-1);
if ( entryIndex < (mappingTableCount-1) ) {
const _shared_region_mapping_np* nextEntry = &mappingTable[entryIndex+1];
if ( (nextEntry->init_prot & VM_PROT_ZF) != 0 ) {
uint64_t segOffset = nextEntry->address - entry->address;
- fprintf(stderr, "%18s at 0x%08lX->0x%08lX\n",
- seg->getName(), (uintptr_t)(seg->getActualLoadAddress() + segOffset), (uintptr_t)(seg->getActualLoadAddress() + segOffset + nextEntry->size - 1));
+ dyld::log("%18s at 0x%08lX->0x%08lX\n",
+ seg->getName(), (uintptr_t)(seg->getActualLoadAddress(this) + segOffset), (uintptr_t)(seg->getActualLoadAddress(this) + segOffset + nextEntry->size - 1));
++entryIndex;
}
}
@@ -673,33 +966,8 @@
const LinkContext& context,
bool usemmap)
{
- const unsigned int segmentCount = fSegments.size();
-
- // adjust base address of segments to pack next to last dylib
- if ( context.slideAndPackDylibs ) {
- uintptr_t lowestReadOnly = (uintptr_t)(-1);
- uintptr_t lowestWritable = (uintptr_t)(-1);
- for(unsigned int segIndex=0; segIndex < segmentCount; ++segIndex){
- Segment* seg = fSegments[segIndex];
- uintptr_t segEnd = seg->getActualLoadAddress();
- if ( seg->writeable() ) {
- if ( segEnd < lowestWritable )
- lowestWritable = segEnd;
- }
- else {
- if ( segEnd < lowestReadOnly )
- lowestReadOnly = segEnd;
- }
- }
- uintptr_t baseAddress;
- if ( lowestWritable - 256*1024*1024 < lowestReadOnly )
- baseAddress = lowestWritable - 256*1024*1024;
- else
- baseAddress = lowestReadOnly;
- // record that we want dylb slid to fgNextSplitSegAddress
- this->setSlide(fgNextSplitSegAddress - baseAddress);
- }
-
+ const unsigned int segmentCount = fSegmentsArrayCount;
+
// build table of segments to map
const unsigned int extraZeroFillEntries = getExtraZeroFillEntriesCount();
const unsigned int mappingTableCount = segmentCount+extraZeroFillEntries;
@@ -712,150 +980,50 @@
if ( usemmap )
r = _shared_region_map_file_with_mmap(fd, mappingTableCount, mappingTable);
else
- r = _shared_region_map_file_np(fd, mappingTableCount, mappingTable, context.slideAndPackDylibs ? NULL : &slide);
+ r = _shared_region_map_file_np(fd, mappingTableCount, mappingTable, &slide);
if ( 0 == r ) {
if ( 0 != slide ) {
slide = (slide) & (-4096); // round down to page boundary
this->setSlide(slide);
}
+ this->setNeverUnload();
if ( context.verboseMapping ) {
if ( slide == 0 )
- fprintf(stderr, "dyld: Mapping split-seg un-shared %s\n", this->getPath());
+ dyld::log("dyld: Mapping split-seg un-shared %s\n", this->getPath());
else
- fprintf(stderr, "dyld: Mapping split-seg un-shared slid by 0x%08llX %s\n", slide, this->getPath());
+ dyld::log("dyld: Mapping split-seg un-shared slid by 0x%08llX %s\n", slide, this->getPath());
for(unsigned int segIndex=0,entryIndex=0; segIndex < segmentCount; ++segIndex, ++entryIndex){
- Segment* seg = fSegments[segIndex];
+ Segment* seg = &fSegmentsArray[segIndex];
const _shared_region_mapping_np* entry = &mappingTable[entryIndex];
if ( (entry->init_prot & VM_PROT_ZF) == 0 )
- fprintf(stderr, "%18s at 0x%08lX->0x%08lX\n",
- seg->getName(), seg->getActualLoadAddress(), seg->getActualLoadAddress()+seg->getFileSize()-1);
+ dyld::log("%18s at 0x%08lX->0x%08lX\n",
+ seg->getName(), seg->getActualLoadAddress(this), seg->getActualLoadAddress(this)+seg->getFileSize()-1);
if ( entryIndex < (mappingTableCount-1) ) {
const _shared_region_mapping_np* nextEntry = &mappingTable[entryIndex+1];
if ( (nextEntry->init_prot & VM_PROT_ZF) != 0 ) {
uint64_t segOffset = nextEntry->address - entry->address;
- fprintf(stderr, "%18s at 0x%08lX->0x%08lX (zerofill)\n",
- seg->getName(), (uintptr_t)(seg->getActualLoadAddress() + segOffset), (uintptr_t)(seg->getActualLoadAddress() + segOffset + nextEntry->size - 1));
+ dyld::log("%18s at 0x%08lX->0x%08lX (zerofill)\n",
+ seg->getName(), (uintptr_t)(seg->getActualLoadAddress(this) + segOffset), (uintptr_t)(seg->getActualLoadAddress(this) + segOffset + nextEntry->size - 1));
++entryIndex;
}
}
}
}
- if ( context.slideAndPackDylibs ) {
- // calculate where next split-seg dylib can load
- uintptr_t largestReadOnly = 0;
- uintptr_t largestWritable = 0;
- for (unsigned int segIndex=0; segIndex < segmentCount; ++segIndex) {
- Segment* seg = fSegments[segIndex];
- uintptr_t segEnd = seg->getActualLoadAddress()+seg->getSize();
- segEnd = (segEnd+4095) & (-4096); // page align
- if ( seg->writeable() ) {
- if ( segEnd > largestWritable )
- largestWritable = segEnd;
- }
- else {
- if ( segEnd > largestReadOnly )
- largestReadOnly = segEnd;
- }
- }
- if ( largestWritable - 256*1024*1024 > largestReadOnly )
- fgNextSplitSegAddress = largestWritable - 256*1024*1024;
- else
- fgNextSplitSegAddress = largestReadOnly;
- }
- }
- if ( context.slideAndPackDylibs && (r != 0) )
- throwf("can't rebase split-seg dylib %s because shared_region_map_file_np() returned %d", this->getPath(), r);
+ }
+ if ( r != 0 )
+ dyld::throwf("can't rebase split-seg dylib %s because shared_region_map_file_np() returned %d", this->getPath(), r);
return r;
}
-
-int
-ImageLoaderMachO::sharedRegionLoadFile(int fd, uint64_t offsetInFat, uint64_t lenInFat, uint64_t fileLen, const LinkContext& context)
-{
-
- // map in split segment file at random address, then tell kernel to share it
- void* loadAddress = 0;
- loadAddress = mmap(NULL, fileLen, PROT_READ, MAP_FILE, fd, 0);
- if ( loadAddress == ((void*)(-1)) )
- throw "mmap error";
-
- // calculate mapping entries
- const unsigned int segmentCount = fSegments.size();
- unsigned int extraZeroFillEntries = getExtraZeroFillEntriesCount();
-
- // build table of segments to map
- const unsigned int mappingTableCount = segmentCount+extraZeroFillEntries;
- const uintptr_t baseAddress = fSegments[0]->getPreferredLoadAddress();
- sf_mapping mappingTable[mappingTableCount];
- initMappingTable(offsetInFat, mappingTable, baseAddress);
-
-
- // use load_shared_file() to map all segments at once
- int flags = 0; // might need to set NEW_LOCAL_SHARED_REGIONS on first use
- static bool firstTime = true;
- if ( firstTime ) {
- // when NEW_LOCAL_SHARED_REGIONS bit is set, this process will get is own shared region
- // this is used by Xcode to prevent development libraries from polluting the global shared segment
- if ( context.sharedRegionMode == kUsePrivateSharedRegion )
- flags |= NEW_LOCAL_SHARED_REGIONS;
- firstTime = false;
- }
-
- caddr_t base_address = (caddr_t)baseAddress;
- kern_return_t r;
- r = load_shared_file( (char*)fPath, // path of file to map shared
- (char*)loadAddress, // beginning of local copy of sharable pages in file
- fileLen, // end of shareable pages in file
- &base_address, // beginning of address range to map
- mappingTableCount, // number of entres in array of sf_mapping
- mappingTable, // the array of sf_mapping
- &flags); // in/out flags
- if ( 0 != r ) {
- // try again but tell kernel it is ok to slide
- flags |= ALTERNATE_LOAD_SITE;
- r = load_shared_file((char*)fPath,(char*)loadAddress, fileLen, &base_address,
- mappingTableCount, mappingTable, &flags);
- }
-
- // unmap file from random address now that they are (hopefully) mapped into the shared region
- munmap(loadAddress, fileLen);
-
- if ( 0 == r ) {
- if ( base_address != (caddr_t)baseAddress )
- this->setSlide((uintptr_t)base_address - baseAddress);
- if ( context.verboseMapping ) {
- if ( base_address != (caddr_t)baseAddress )
- fprintf(stderr, "dyld: Mapping split-seg load_shared_alt_region %s\n", this->getPath());
- else
- fprintf(stderr, "dyld: Mapping split-seg load_shared %s\n", this->getPath());
- for(unsigned int segIndex=0,entryIndex=0; segIndex < segmentCount; ++segIndex, ++entryIndex){
- Segment* seg = fSegments[segIndex];
- const sf_mapping* entry = &mappingTable[entryIndex];
- if ( (entry->protection & VM_PROT_ZF) == 0 )
- fprintf(stderr, "%18s at 0x%08lX->0x%08lX\n",
- seg->getName(), seg->getActualLoadAddress(), seg->getActualLoadAddress()+seg->getFileSize()-1);
- if ( entryIndex < (mappingTableCount-1) ) {
- const sf_mapping* nextEntry = &mappingTable[entryIndex+1];
- if ( (nextEntry->protection & VM_PROT_ZF) != 0 ) {
- fprintf(stderr, "%18s at 0x%08lX->0x%08lX\n",
- seg->getName(), (uintptr_t)(nextEntry->mapping_offset + base_address), (uintptr_t)(nextEntry->mapping_offset + base_address + nextEntry->size - 1));
- ++entryIndex;
- }
- }
- }
- }
- }
- return r;
-}
void
ImageLoaderMachO::initMappingTable(uint64_t offsetInFat,
sf_mapping *mappingTable,
uintptr_t baseAddress)
{
- unsigned int segmentCount = fSegments.size();
+ unsigned int segmentCount = fSegmentsArrayCount;
for(unsigned int segIndex=0,entryIndex=0; segIndex < segmentCount; ++segIndex, ++entryIndex){
- Segment* seg = fSegments[segIndex];
+ Segment* seg = &fSegmentsArray[segIndex];
sf_mapping* entry = &mappingTable[entryIndex];
entry->mapping_offset = seg->getPreferredLoadAddress() - baseAddress;
entry->size = seg->getFileSize();
@@ -882,7 +1050,8 @@
}
}
-#endif // !__LP64__ split segs not supported for 64-bits
+#endif // SPLIT_SEG_SHARED_REGION_SUPPORT
+
void ImageLoaderMachO::setSlide(intptr_t slide)
@@ -893,26 +1062,41 @@
void ImageLoaderMachO::parseLoadCmds()
{
// now that segments are mapped in, get real fMachOData, fLinkEditBase, and fSlide
- const unsigned int segmentCount = fSegments.size();
- for(unsigned int i=0; i < segmentCount; ++i){
- Segment* seg = fSegments[i];
+ for (ImageLoader::SegmentIterator it = this->beginSegments(); it != this->endSegments(); ++it ) {
+ Segment* seg = *it;
// set up pointer to __LINKEDIT segment
if ( strcmp(seg->getName(),"__LINKEDIT") == 0 )
- fLinkEditBase = (uint8_t*)(seg->getActualLoadAddress() - seg->getFileOffset());
+ fLinkEditBase = (uint8_t*)(seg->getActualLoadAddress(this) - seg->getFileOffset());
+#if TEXT_RELOC_SUPPORT
// __TEXT segment always starts at beginning of file and contains mach_header and load commands
if ( strcmp(seg->getName(),"__TEXT") == 0 ) {
- if ( seg->hasFixUps() )
+ if ( ((SegmentMachO*)seg)->hasFixUps() )
fTextSegmentWithFixups = (SegmentMachO*)seg;
}
+#endif
+#if __i386__
+ if ( seg->readOnlyImportStubs() )
+ fReadOnlyImportSegment = (SegmentMachO*)seg;
+#endif
// some segment always starts at beginning of file and contains mach_header and load commands
if ( (seg->getFileOffset() == 0) && (seg->getFileSize() != 0) ) {
- fMachOData = (uint8_t*)(seg->getActualLoadAddress());
- }
- }
-
+ fMachOData = (uint8_t*)(seg->getActualLoadAddress(this));
+ }
+ #if __ppc64__
+ // in 10.5 to support images that span 4GB (including pagezero) switch meaning of r_address
+ if ( ((seg->getPreferredLoadAddress() + seg->getSize() - fSegmentsArray[0].getPreferredLoadAddress()) > 0x100000000)
+ && seg->writeable() )
+ f4GBWritable = true;
+ #endif
+ }
+
// keep count of prebound images with weak exports
if ( this->hasCoalescedExports() )
++fgCountOfImagesWithWeakExports;
+
+ // keep count of images used in shared cache
+ if ( fInSharedCache )
+ ++fgImagesUsedFromSharedCache;
// walk load commands (mapped in at start of __TEXT segment)
const uint32_t cmd_count = ((macho_header*)fMachOData)->ncmds;
@@ -934,34 +1118,34 @@
fHasSubUmbrella = true;
break;
case LC_SUB_FRAMEWORK:
- {
- const struct sub_framework_command* subf = (struct sub_framework_command*)cmd;
- fReExportThruFramework = (char*)cmd + subf->umbrella.offset;
- }
+ fInUmbrella = true;
break;
case LC_SUB_LIBRARY:
fHasSubLibraries = true;
break;
case LC_ROUTINES_COMMAND:
- fDashInit = (struct macho_routines_command*)cmd;
+ fHasDashInit = true;
break;
case LC_SEGMENT_COMMAND:
{
const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
+#if IMAGE_NOTIFY_SUPPORT
const bool isDataSeg = (strcmp(seg->segname, "__DATA") == 0);
+#endif
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_MOD_INIT_FUNC_POINTERS )
- fModInitSection = sect;
+ fHasInitializers = true;
else if ( type == S_MOD_TERM_FUNC_POINTERS )
- fModTermSection = sect;
- else if ( isDataSeg && (strcmp(sect->sectname, "__dyld") == 0) ) {
- fDATAdyld = sect;
- }
+ fHasTerminators = true;
+ else if ( type == S_DTRACE_DOF )
+ fHasDOFSections = true;
+#if IMAGE_NOTIFY_SUPPORT
else if ( isDataSeg && (strcmp(sect->sectname, "__image_notify") == 0) )
- fImageNotifySection = sect;
+ fHasImageNotifySection = true;
+#endif
}
}
break;
@@ -973,12 +1157,14 @@
fDylibID = (struct dylib_command*)cmd;
}
break;
+ case LC_RPATH:
case LC_LOAD_WEAK_DYLIB:
+ case LC_REEXPORT_DYLIB:
// do nothing, just prevent LC_REQ_DYLD exception from occuring
break;
default:
if ( (cmd->cmd & LC_REQ_DYLD) != 0 )
- throwf("unknown required load command 0x%08X", cmd->cmd);
+ dyld::throwf("unknown required load command 0x%08X", cmd->cmd);
}
cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
}
@@ -998,23 +1184,33 @@
// test if this image is re-exported through parent (the image that loaded this one)
bool ImageLoaderMachO::isSubframeworkOf(const LinkContext& context, const ImageLoader* parent) const
{
- if ( fReExportThruFramework != NULL ) {
- // need to match LC_SUB_FRAMEWORK string against the leaf name of the install location of parent...
- const char* parentInstallPath = parent->getInstallPath();
- if ( parentInstallPath != NULL ) {
- const char* lastSlash = strrchr(parentInstallPath, '/');
- if ( lastSlash != NULL ) {
- if ( strcmp(&lastSlash[1], fReExportThruFramework) == 0 )
- return true;
- if ( context.imageSuffix != NULL ) {
- // when DYLD_IMAGE_SUFFIX is used, lastSlash string needs imageSuffix removed from end
- char reexportAndSuffix[strlen(context.imageSuffix)+strlen(fReExportThruFramework)+1];
- strcpy(reexportAndSuffix, fReExportThruFramework);
- strcat(reexportAndSuffix, context.imageSuffix);
- if ( strcmp(&lastSlash[1], reexportAndSuffix) == 0 )
- return true;
+ if ( fInUmbrella ) {
+ 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) {
+ if (cmd->cmd == LC_SUB_FRAMEWORK) {
+ const struct sub_framework_command* subf = (struct sub_framework_command*)cmd;
+ const char* exportThruName = (char*)cmd + subf->umbrella.offset;
+ // need to match LC_SUB_FRAMEWORK string against the leaf name of the install location of parent...
+ const char* parentInstallPath = parent->getInstallPath();
+ if ( parentInstallPath != NULL ) {
+ const char* lastSlash = strrchr(parentInstallPath, '/');
+ if ( lastSlash != NULL ) {
+ if ( strcmp(&lastSlash[1], exportThruName) == 0 )
+ return true;
+ if ( context.imageSuffix != NULL ) {
+ // when DYLD_IMAGE_SUFFIX is used, lastSlash string needs imageSuffix removed from end
+ char reexportAndSuffix[strlen(context.imageSuffix)+strlen(exportThruName)+1];
+ strcpy(reexportAndSuffix, exportThruName);
+ strcat(reexportAndSuffix, context.imageSuffix);
+ if ( strcmp(&lastSlash[1], reexportAndSuffix) == 0 )
+ return true;
+ }
+ }
}
}
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
}
}
return false;
@@ -1101,7 +1297,8 @@
return false;
}
-
+
+
void* ImageLoaderMachO::getMain() const
{
const uint32_t cmd_count = ((macho_header*)fMachOData)->ncmds;
@@ -1113,13 +1310,16 @@
{
#if __ppc__
const ppc_thread_state_t* registers = (ppc_thread_state_t*)(((char*)cmd) + 16);
- return (void*)registers->srr0;
+ return (void*)(registers->srr0 + fSlide);
#elif __ppc64__
const ppc_thread_state64_t* registers = (ppc_thread_state64_t*)(((char*)cmd) + 16);
- return (void*)registers->srr0;
+ return (void*)(registers->srr0 + fSlide);
#elif __i386__
const i386_thread_state_t* registers = (i386_thread_state_t*)(((char*)cmd) + 16);
- return (void*)registers->eip;
+ return (void*)(registers->eip + fSlide);
+ #elif __x86_64__
+ const x86_thread_state64_t* registers = (x86_thread_state64_t*)(((char*)cmd) + 16);
+ return (void*)(registers->rip + fSlide);
#else
#warning need processor specific code
#endif
@@ -1142,6 +1342,7 @@
switch (cmd->cmd) {
case LC_LOAD_DYLIB:
case LC_LOAD_WEAK_DYLIB:
+ case LC_REEXPORT_DYLIB:
++count;
break;
}
@@ -1150,7 +1351,7 @@
return count;
}
-void ImageLoaderMachO::doGetDependentLibraries(DependentLibrary libs[])
+void ImageLoaderMachO::doGetDependentLibraries(DependentLibraryInfo libs[])
{
uint32_t index = 0;
const uint32_t cmd_count = ((macho_header*)fMachOData)->ncmds;
@@ -1160,18 +1361,17 @@
switch (cmd->cmd) {
case LC_LOAD_DYLIB:
case LC_LOAD_WEAK_DYLIB:
+ case LC_REEXPORT_DYLIB:
{
const struct dylib_command* dylib = (struct dylib_command*)cmd;
- DependentLibrary* lib = &libs[index++];
+ DependentLibraryInfo* lib = &libs[index++];
lib->name = (char*)cmd + dylib->dylib.name.offset;
//lib->name = strdup((char*)cmd + dylib->dylib.name.offset);
- lib->image = NULL;
lib->info.checksum = dylib->dylib.timestamp;
lib->info.minVersion = dylib->dylib.compatibility_version;
lib->info.maxVersion = dylib->dylib.current_version;
- lib->required = (cmd->cmd == LC_LOAD_DYLIB);
- lib->checksumMatches = false;
- lib->isReExported = false;
+ lib->required = (cmd->cmd != LC_LOAD_WEAK_DYLIB);
+ lib->reExported = (cmd->cmd == LC_REEXPORT_DYLIB);
}
break;
}
@@ -1195,29 +1395,94 @@
return info;
}
+void ImageLoaderMachO::getRPaths(const LinkContext& context, std::vector<const char*>& paths) const
+{
+ 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 (unsigned long i = 0; i < cmd_count; ++i) {
+ switch (cmd->cmd) {
+ case LC_RPATH:
+ const char* path = (char*)cmd + ((struct rpath_command*)cmd)->path.offset;
+ if ( strncmp(path, "@loader_path/", 13) == 0 ) {
+ if ( issetugid() && (context.mainExecutable == this) ) {
+ dyld::warn("LC_RPATH %s in %s being ignored in setuid program because of @loader_path\n", path, this->getPath());
+ break;
+ }
+ char resolvedPath[PATH_MAX];
+ if ( realpath(this->getPath(), resolvedPath) != NULL ) {
+ char newRealPath[strlen(resolvedPath) + strlen(path)];
+ strcpy(newRealPath, resolvedPath);
+ char* addPoint = strrchr(newRealPath,'/');
+ if ( addPoint != NULL )
+ strcpy(&addPoint[1], &path[13]);
+ else
+ strcpy(newRealPath, &path[13]);
+ path = strdup(newRealPath);
+ }
+ }
+ else if ( strncmp(path, "@executable_path/", 17) == 0 ) {
+ if ( issetugid() ) {
+ dyld::warn("LC_RPATH %s in %s being ignored in setuid program because of @executable_path\n", path, this->getPath());
+ break;
+ }
+ char resolvedPath[PATH_MAX];
+ if ( realpath(context.mainExecutable->getPath(), resolvedPath) != NULL ) {
+ char newRealPath[strlen(resolvedPath) + strlen(path)];
+ strcpy(newRealPath, resolvedPath);
+ char* addPoint = strrchr(newRealPath,'/');
+ if ( addPoint != NULL )
+ strcpy(&addPoint[1], &path[17]);
+ else
+ strcpy(newRealPath, &path[17]);
+ path = strdup(newRealPath);
+ }
+ }
+ else if ( (path[0] != '/') && issetugid() ) {
+ dyld::warn("LC_RPATH %s in %s being ignored in setuid program because it is a relative path\n", path, this->getPath());
+ break;
+ }
+ else {
+ // make copy so that all elements of 'paths' can be freed
+ path = strdup(path);
+ }
+ paths.push_back(path);
+ break;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+}
+
uintptr_t ImageLoaderMachO::getFirstWritableSegmentAddress()
{
// in split segment libraries r_address is offset from first writable segment
- for (std::vector<class Segment*>::iterator it=fSegments.begin(); it != fSegments.end(); ++it) {
- if ( (*it)->writeable() ) {
- return (*it)->getActualLoadAddress();
- }
+ for(ImageLoader::SegmentIterator it = this->beginSegments(); it != this->endSegments(); ++it ) {
+ Segment* seg = *it;
+ if ( seg->writeable() )
+ return seg->getActualLoadAddress(this);
}
throw "no writable segment";
}
uintptr_t ImageLoaderMachO::getRelocBase()
{
+ // r_address is either an offset from the first segment address
+ // or from the first writable segment address
#if __ppc__ || __i386__
- if ( fIsSplitSeg ) {
- // in split segment libraries r_address is offset from first writable segment
+ if ( fIsSplitSeg )
return getFirstWritableSegmentAddress();
- }
-#endif
-
- // in non-split segment libraries r_address is offset from first segment
- return fSegments[0]->getActualLoadAddress();
-}
+ else
+ return fSegmentsArray[0].getActualLoadAddress(this);
+#elif __ppc64__
+ if ( f4GBWritable )
+ return getFirstWritableSegmentAddress();
+ else
+ return fSegmentsArray[0].getActualLoadAddress(this);
+#elif __x86_64__
+ return getFirstWritableSegmentAddress();
+#endif
+}
+
#if __ppc__
static inline void otherRelocsPPC(uintptr_t* locationToFix, uint8_t relocationType, uint16_t otherHalf, uintptr_t slide)
@@ -1242,55 +1507,113 @@
instruction->immediateValue = temp >> 16;
}
//uint32_t after = *((uint32_t*)locationToFix);
- //fprintf(stderr, "dyld: ppc fixup %0p type %d from 0x%08X to 0x%08X\n", locationToFix, relocationType, before, after);
+ //dyld::log("dyld: ppc fixup %0p type %d from 0x%08X to 0x%08X\n", locationToFix, relocationType, before, after);
+}
+#endif
+
+#if __ppc__ || __i386__
+void ImageLoaderMachO::resetPreboundLazyPointers(const LinkContext& context, uintptr_t relocBase)
+{
+ // loop through all local (internal) relocation records looking for pre-bound-lazy-pointer values
+ register const uintptr_t slide = this->fSlide;
+ const relocation_info* const relocsStart = (struct relocation_info*)(&fLinkEditBase[fDynamicInfo->locreloff]);
+ const relocation_info* const relocsEnd = &relocsStart[fDynamicInfo->nlocrel];
+ for (const relocation_info* reloc=relocsStart; reloc < relocsEnd; ++reloc) {
+ if ( (reloc->r_address & R_SCATTERED) != 0 ) {
+ const struct scattered_relocation_info* sreloc = (struct scattered_relocation_info*)reloc;
+ if (sreloc->r_length == RELOC_SIZE) {
+ uintptr_t* locationToFix = (uintptr_t*)(sreloc->r_address + relocBase);
+ switch(sreloc->r_type) {
+ #if __ppc__
+ case PPC_RELOC_PB_LA_PTR:
+ *locationToFix = sreloc->r_value + slide;
+ break;
+ #endif
+ #if __i386__
+ case GENERIC_RELOC_PB_LA_PTR:
+ *locationToFix = sreloc->r_value + slide;
+ break;
+ #endif
+ }
+ }
+ }
+ }
}
#endif
void ImageLoaderMachO::doRebase(const LinkContext& context)
{
// if prebound and loaded at prebound address, then no need to rebase
- // Note: you might think that the check for allDependentLibrariesAsWhenPreBound() is not needed
- // but it is. If a dependent library changed, this image's lazy pointers into that library
- // need to be updated (reset back to lazy binding handler). That work is done most easily
- // here because there is a PPC_RELOC_PB_LA_PTR reloc record for each lazy pointer.
- if ( this->usablePrebinding(context) && this->usesTwoLevelNameSpace() ) {
- // skip rebasing cause prebound and prebinding not disabled
+ if ( this->usablePrebinding(context) ) {
+ // skip rebasing because prebinding is valid
++fgImagesWithUsedPrebinding; // bump totals for statistics
return;
}
-
+
// print why prebinding was not used
if ( context.verbosePrebinding ) {
if ( !this->isPrebindable() ) {
- fprintf(stderr, "dyld: image not prebound, so could not use prebinding in %s\n", this->getPath());
+ dyld::log("dyld: image not prebound, so could not use prebinding in %s\n", this->getPath());
}
else if ( fSlide != 0 ) {
- fprintf(stderr, "dyld: image slid, so could not use prebinding in %s\n", this->getPath());
+ dyld::log("dyld: image slid, so could not use prebinding in %s\n", this->getPath());
}
else if ( !this->allDependentLibrariesAsWhenPreBound() ) {
- fprintf(stderr, "dyld: dependent libraries changed, so could not use prebinding in %s\n", this->getPath());
+ dyld::log("dyld: dependent libraries changed, so could not use prebinding in %s\n", this->getPath());
}
else if ( !this->usesTwoLevelNameSpace() ){
- fprintf(stderr, "dyld: image uses flat-namespace so, parts of prebinding ignored %s\n", this->getPath());
+ dyld::log("dyld: image uses flat-namespace so, parts of prebinding ignored %s\n", this->getPath());
}
else {
- fprintf(stderr, "dyld: environment variable disabled use of prebinding in %s\n", this->getPath());
- }
- }
-
+ dyld::log("dyld: environment variable disabled use of prebinding in %s\n", this->getPath());
+ }
+ }
+
+ // cache values that are used in the following loop
+ const uintptr_t relocBase = this->getRelocBase();
+ register const uintptr_t slide = this->fSlide;
+
+ //dyld::log("slide=0x%08lX for %s\n", slide, this->getPath());
+
+#if __ppc__ || __i386__
+ // if prebound and we got here, then prebinding is not valid, so reset all lazy pointers
+ // if this image is in the shared cache, do not reset, they will be bound in doBind()
+ if ( this->isPrebindable() && !fInSharedCache )
+ this->resetPreboundLazyPointers(context, relocBase);
+#endif
+
+ // if in shared cache and got here, then we depend on something not in the shared cache
+ if ( fInSharedCache )
+ context.notifySharedCacheInvalid();
+
+ // if loaded at preferred address, no rebasing necessary
+ if ( slide == 0 )
+ return;
+
+#if TEXT_RELOC_SUPPORT
// if there are __TEXT fixups, temporarily make __TEXT writable
if ( fTextSegmentWithFixups != NULL )
- fTextSegmentWithFixups->tempWritable();
-
- // cache this value that is used in the following loop
- register const uintptr_t slide = this->fSlide;
-
+ fTextSegmentWithFixups->tempWritable(context, this);
+#endif
// loop through all local (internal) relocation records
- const uintptr_t relocBase = this->getRelocBase();
const relocation_info* const relocsStart = (struct relocation_info*)(&fLinkEditBase[fDynamicInfo->locreloff]);
const relocation_info* const relocsEnd = &relocsStart[fDynamicInfo->nlocrel];
for (const relocation_info* reloc=relocsStart; reloc < relocsEnd; ++reloc) {
- #if __ppc__ || __ppc64__ || __i386__
+#if LINKEDIT_USAGE_DEBUG
+ noteAccessedLinkEditAddress(reloc);
+#endif
+ #if __x86_64__
+ // only one kind of local relocation supported for x86_64
+ if ( reloc->r_length != 3 )
+ throw "bad local relocation length";
+ if ( reloc->r_type != X86_64_RELOC_UNSIGNED )
+ throw "unknown local relocation type";
+ if ( reloc->r_pcrel != 0 )
+ throw "bad local relocation pc_rel";
+ if ( reloc->r_extern != 0 )
+ throw "extern relocation found with local relocations";
+ *((uintptr_t*)(reloc->r_address + relocBase)) += slide;
+ #else
if ( (reloc->r_address & R_SCATTERED) == 0 ) {
if ( reloc->r_symbolnum == R_ABS ) {
// ignore absolute relocations
@@ -1325,12 +1648,6 @@
case GENERIC_RELOC_VANILLA:
*locationToFix += slide;
break;
- #if __ppc__ || __ppc64__
- case PPC_RELOC_PB_LA_PTR:
- // should only see these in prebound images, and we got here so prebinding is being ignored
- *locationToFix = sreloc->r_value + slide;
- break;
- #endif
#if __ppc__
case PPC_RELOC_HI16:
case PPC_RELOC_LO16:
@@ -1339,11 +1656,18 @@
++reloc; // these relocations come in pairs, get next one
otherRelocsPPC(locationToFix, sreloc->r_type, reloc->r_address, slide);
break;
- #endif
- #if __i386__
+ case PPC_RELOC_PB_LA_PTR:
+ // do nothing
+ break;
+ #elif __ppc64__
+ case PPC_RELOC_PB_LA_PTR:
+ // needed for compatibility with ppc64 binaries built with the first ld64
+ // which used PPC_RELOC_PB_LA_PTR relocs instead of GENERIC_RELOC_VANILLA for lazy pointers
+ *locationToFix += slide;
+ break;
+ #elif __i386__
case GENERIC_RELOC_PB_LA_PTR:
- // should only see these in prebound images, and we got here so prebinding is being ignored
- *locationToFix = sreloc->r_value + slide;
+ // do nothing
break;
#endif
default:
@@ -1354,22 +1678,23 @@
throw "bad local scattered relocation length";
}
}
- #endif
- }
-
+ #endif // x86_64
+ }
+
+#if TEXT_RELOC_SUPPORT
// if there were __TEXT fixups, restore write protection
if ( fTextSegmentWithFixups != NULL ) {
- fTextSegmentWithFixups->setPermissions();
- sys_icache_invalidate((void*)fTextSegmentWithFixups->getActualLoadAddress(), fTextSegmentWithFixups->getSize());
- }
-
+ fTextSegmentWithFixups->setPermissions(context,this);
+ sys_icache_invalidate((void*)fTextSegmentWithFixups->getActualLoadAddress(this), fTextSegmentWithFixups->getSize());
+ }
+#endif
// update stats
fgTotalRebaseFixups += fDynamicInfo->nlocrel;
}
const struct macho_nlist* ImageLoaderMachO::binarySearchWithToc(const char* key, const char stringPool[], const struct macho_nlist symbols[],
- const struct dylib_table_of_contents toc[], uint32_t symbolCount, uint32_t hintIndex)
+ const struct dylib_table_of_contents toc[], uint32_t symbolCount, uint32_t hintIndex) const
{
int32_t high = symbolCount-1;
int32_t mid = hintIndex;
@@ -1382,6 +1707,9 @@
else {
++ImageLoaderMachO::fgHintedBinaryTreeSearchs;
}
+ ++fgTotalBindImageSearches;
+
+ //dyld::log("dyld: binarySearchWithToc for %s in %s\n", key, this->getShortName());
for (int32_t low = 0; low <= high; mid = (low+high)/2) {
const uint32_t index = toc[mid].symbol_index;
@@ -1407,9 +1735,15 @@
return NULL;
}
-const struct macho_nlist* ImageLoaderMachO::binarySearch(const char* key, const char stringPool[], const struct macho_nlist symbols[], uint32_t symbolCount)
-{
+const struct macho_nlist* ImageLoaderMachO::binarySearch(const char* key, const char stringPool[], const struct macho_nlist symbols[], uint32_t symbolCount) const
+{
+ // update stats
+ ++fgTotalBindImageSearches;
++ImageLoaderMachO::fgUnhintedBinaryTreeSearchs;
+
+ //dyld::log("dyld: binarySearch for %s in %s, stringpool=%p, symbols=%p, symbolCount=%u\n",
+ // key, this->getShortName(), stringPool, symbols, symbolCount);
+
const struct macho_nlist* base = symbols;
for (uint32_t n = symbolCount; n > 0; n /= 2) {
const struct macho_nlist* pivot = &base[n/2];
@@ -1435,7 +1769,7 @@
return NULL;
}
-const ImageLoader::Symbol* ImageLoaderMachO::findExportedSymbol(const char* name, const void* hint, bool searchReExports, ImageLoader** foundIn) const
+const ImageLoader::Symbol* ImageLoaderMachO::findExportedSymbol(const char* name, const void* hint, bool searchReExports, const ImageLoader** foundIn) const
{
const struct macho_nlist* sym = NULL;
const struct twolevel_hint* theHint = (struct twolevel_hint*)hint;
@@ -1524,15 +1858,22 @@
}
}
-
+
return NULL;
}
-uintptr_t ImageLoaderMachO::getExportedSymbolAddress(const Symbol* sym) const
-{
- const struct macho_nlist* nlistSym = (const struct macho_nlist*)sym;
- return nlistSym->n_value + fSlide;
+
+
+uintptr_t ImageLoaderMachO::getExportedSymbolAddress(const Symbol* sym, const LinkContext& context, const ImageLoader* requestor) const
+{
+ return this->getSymbolAddress((const struct macho_nlist*)sym, requestor, context);
+}
+
+uintptr_t ImageLoaderMachO::getSymbolAddress(const struct macho_nlist* sym, const ImageLoader* requestor, const LinkContext& context) const
+{
+ uintptr_t result = sym->n_value + fSlide;
+ return result;
}
ImageLoader::DefinitionFlags ImageLoaderMachO::getExportedSymbolInfo(const Symbol* sym) const
@@ -1679,34 +2020,38 @@
static void __attribute__((noreturn)) throwSymbolNotFound(const char* symbol, const char* referencedFrom, const char* expectedIn)
{
- const char* formatString = "Symbol not found: %s\n Referenced from: %s\n Expected in: %s\n";
- char buf[strlen(symbol)+strlen(referencedFrom)+strlen(expectedIn)+strlen(formatString)];
- sprintf(buf, formatString, symbol, referencedFrom, expectedIn);
- throw strdup(buf); // this is a leak if exception doesn't halt program
-}
-
-uintptr_t ImageLoaderMachO::resolveUndefined(const LinkContext& context, const struct macho_nlist* undefinedSymbol, bool twoLevel, ImageLoader** foundIn)
-{
+ dyld::throwf("Symbol not found: %s\n Referenced from: %s\n Expected in: %s\n", symbol, referencedFrom, expectedIn);
+}
+
+uintptr_t ImageLoaderMachO::resolveUndefined(const LinkContext& context, const struct macho_nlist* undefinedSymbol, bool twoLevel, const ImageLoader** foundIn)
+{
+ ++fgTotalBindSymbolsResolved;
const char* symbolName = &fStrings[undefinedSymbol->n_un.n_strx];
+#if LINKEDIT_USAGE_DEBUG
+ noteAccessedLinkEditAddress(undefinedSymbol);
+ noteAccessedLinkEditAddress(symbolName);
+#endif
if ( context.bindFlat || !twoLevel ) {
// flat lookup
+ if ( ((undefinedSymbol->n_type & N_PEXT) != 0) && ((undefinedSymbol->n_type & N_TYPE) == N_SECT) ) {
+ // is a multi-module private_extern internal reference that the linker did not optimize away
+ uintptr_t addr = this->getSymbolAddress(undefinedSymbol, this, context);
+ *foundIn = this;
+ return addr;
+ }
const Symbol* sym;
- if ( context.flatExportFinder(symbolName, &sym, foundIn) )
- return (*foundIn)->getExportedSymbolAddress(sym);
+ if ( context.flatExportFinder(symbolName, &sym, foundIn) ) {
+ if ( (*foundIn != this) && !(*foundIn)->neverUnload() )
+ this->addDynamicReference(*foundIn);
+ return (*foundIn)->getExportedSymbolAddress(sym, context, this);
+ }
// if a bundle is loaded privately the above will not find its exports
if ( this->isBundle() && this->hasHiddenExports() ) {
// look in self for needed symbol
sym = this->findExportedSymbol(symbolName, NULL, false, foundIn);
if ( sym != NULL )
- return (*foundIn)->getExportedSymbolAddress(sym);
- }
- if ( ((undefinedSymbol->n_type & N_PEXT) != 0) || ((undefinedSymbol->n_type & N_TYPE) == N_SECT) ) {
- // could be a multi-module private_extern internal reference
- // the static linker squirrels away the target address in n_value
- uintptr_t addr = undefinedSymbol->n_value + this->fSlide;
- *foundIn = this;
- return addr;
+ return (*foundIn)->getExportedSymbolAddress(sym, context, this);
}
if ( (undefinedSymbol->n_desc & N_WEAK_REF) != 0 ) {
// definition can't be found anywhere
@@ -1716,15 +2061,26 @@
throwSymbolNotFound(symbolName, this->getPath(), "flat namespace");
}
else {
- // symbol requires searching images with coalesced symbols
- if ( this->needsCoalescing() && symbolRequiresCoalescing(undefinedSymbol) ) {
+ // symbol requires searching images with coalesced symbols (not done during prebinding)
+ if ( !context.prebinding && this->needsCoalescing() && symbolRequiresCoalescing(undefinedSymbol) ) {
const Symbol* sym;
- if ( context.coalescedExportFinder(symbolName, &sym, foundIn) )
- return (*foundIn)->getExportedSymbolAddress(sym);
+ if ( context.coalescedExportFinder(symbolName, &sym, foundIn) ) {
+ if ( (*foundIn != this) && !(*foundIn)->neverUnload() )
+ this->addDynamicReference(*foundIn);
+ return (*foundIn)->getExportedSymbolAddress(sym, context, this);
+ }
//throwSymbolNotFound(symbolName, this->getPath(), "coalesced namespace");
- //fprintf(stderr, "dyld: coalesced symbol %s not found in any coalesced image, falling back to two-level lookup", symbolName);
+ //dyld::log("dyld: coalesced symbol %s not found in any coalesced image, falling back to two-level lookup", symbolName);
}
+ // if this is a real definition (not an undefined symbol) there is no ordinal
+ if ( (undefinedSymbol->n_type & N_TYPE) == N_SECT ) {
+ // static linker should never generate this case, but if it does, do something sane
+ uintptr_t addr = this->getSymbolAddress(undefinedSymbol, this, context);
+ *foundIn = this;
+ return addr;
+ }
+
// two level lookup
void* hint = NULL;
ImageLoader* target = NULL;
@@ -1740,13 +2096,13 @@
// flat lookup
const Symbol* sym;
if ( context.flatExportFinder(symbolName, &sym, foundIn) )
- return (*foundIn)->getExportedSymbolAddress(sym);
+ return (*foundIn)->getExportedSymbolAddress(sym, context, this);
// no image has exports this symbol
// either report error or hope ZeroLink can just-in-time load an image
context.undefinedHandler(symbolName);
// try looking again
if ( context.flatExportFinder(symbolName, &sym, foundIn) )
- return (*foundIn)->getExportedSymbolAddress(sym);
+ return (*foundIn)->getExportedSymbolAddress(sym, context, this);
throwSymbolNotFound(symbolName, this->getPath(), "dynamic lookup");
}
@@ -1759,11 +2115,12 @@
}
}
else {
- throw "corrupt binary, library ordinal too big";
+ dyld::throwf("bad mach-o binary, library ordinal (%u) too big (max %u) for symbol %s in %s",
+ ord, fLibrariesCount, symbolName, this->getPath());
}
if ( target == NULL ) {
- fprintf(stderr, "resolveUndefined(%s) in %s\n", symbolName, this->getPath());
+ //dyld::log("resolveUndefined(%s) in %s\n", symbolName, this->getPath());
throw "symbol not found";
}
@@ -1780,12 +2137,12 @@
const Symbol* sym = target->findExportedSymbol(symbolName, hint, true, foundIn);
if ( sym!= NULL ) {
- return (*foundIn)->getExportedSymbolAddress(sym);
+ return (*foundIn)->getExportedSymbolAddress(sym, context, this);
}
else if ( (undefinedSymbol->n_type & N_PEXT) != 0 ) {
// don't know why the static linker did not eliminate the internal reference to a private extern definition
*foundIn = this;
- return undefinedSymbol->n_value + fSlide;
+ return this->getSymbolAddress(undefinedSymbol, this, context);
}
else if ( (undefinedSymbol->n_desc & N_WEAK_REF) != 0 ) {
// if definition not found and reference is weak return 0
@@ -1831,14 +2188,15 @@
const bool twoLevel = this->usesTwoLevelNameSpace();
const bool prebound = this->isPrebindable();
+#if TEXT_RELOC_SUPPORT
// if there are __TEXT fixups, temporarily make __TEXT writable
if ( fTextSegmentWithFixups != NULL )
- fTextSegmentWithFixups->tempWritable();
-
+ fTextSegmentWithFixups->tempWritable(context, this);
+#endif
// cache last lookup
- const struct macho_nlist* lastUndefinedSymbol = 0;
+ const struct macho_nlist* lastUndefinedSymbol = NULL;
uintptr_t symbolAddr = 0;
- ImageLoader* image = NULL;
+ const ImageLoader* image = NULL;
// loop through all external relocation records and bind each
const relocation_info* const relocsStart = (struct relocation_info*)(&fLinkEditBase[fDynamicInfo->extreloff]);
@@ -1854,6 +2212,7 @@
continue;
uintptr_t* location = ((uintptr_t*)(reloc->r_address + relocBase));
uintptr_t value = *location;
+ bool symbolAddrCached = true;
#if __i386__
if ( reloc->r_pcrel ) {
value += (uintptr_t)location + 4 - fSlide;
@@ -1884,21 +2243,25 @@
if ( undefinedSymbol != lastUndefinedSymbol ) {
symbolAddr = this->resolveUndefined(context, undefinedSymbol, twoLevel, &image);
lastUndefinedSymbol = undefinedSymbol;
+ symbolAddrCached = false;
}
if ( context.verboseBind ) {
const char *path = NULL;
- if(NULL != image) {
+ if ( image != NULL ) {
path = image->getShortName();
}
- if(0 == value) {
- fprintf(stderr, "dyld: bind: %s:0x%08lx = %s:%s, *0x%08lx = 0x%08lx\n",
+ const char* cachedString = "(cached)";
+ if ( !symbolAddrCached )
+ cachedString = "";
+ if ( value == 0 ) {
+ dyld::log("dyld: bind: %s:0x%08lX = %s:%s, *0x%08lX = 0x%08lX%s\n",
this->getShortName(), (uintptr_t)location,
- path, &fStrings[undefinedSymbol->n_un.n_strx], (uintptr_t)location, symbolAddr);
+ path, &fStrings[undefinedSymbol->n_un.n_strx], (uintptr_t)location, symbolAddr, cachedString);
}
else {
- fprintf(stderr, "dyld: bind: %s:0x%08lx = %s:%s, *0x%08lx = 0x%08lx + %ld\n",
+ dyld::log("dyld: bind: %s:0x%08lX = %s:%s, *0x%08lX = 0x%08lX%s + %ld\n",
this->getShortName(), (uintptr_t)location,
- path, &fStrings[undefinedSymbol->n_un.n_strx], (uintptr_t)location, symbolAddr, value);
+ path, &fStrings[undefinedSymbol->n_un.n_strx], (uintptr_t)location, symbolAddr, cachedString, value);
}
}
value += symbolAddr;
@@ -1916,6 +2279,8 @@
if ( !prebound || (*location != value) )
*location = value;
#endif
+ // update stats
+ ++fgTotalBindFixups;
}
break;
default:
@@ -1927,14 +2292,13 @@
}
}
+#if TEXT_RELOC_SUPPORT
// if there were __TEXT fixups, restore write protection
if ( fTextSegmentWithFixups != NULL ) {
- fTextSegmentWithFixups->setPermissions();
- sys_icache_invalidate((void*)fTextSegmentWithFixups->getActualLoadAddress(), fTextSegmentWithFixups->getSize());
- }
-
- // update stats
- fgTotalBindFixups += fDynamicInfo->nextrel;
+ fTextSegmentWithFixups->setPermissions(context, this);
+ sys_icache_invalidate((void*)fTextSegmentWithFixups->getActualLoadAddress(this), fTextSegmentWithFixups->getSize());
+ }
+#endif
}
const mach_header* ImageLoaderMachO::machHeader() const
@@ -1948,19 +2312,25 @@
}
// hmm. maybe this should be up in ImageLoader??
-const void* ImageLoaderMachO::getBaseAddress() const
-{
- Segment* seg = fSegments[0];
- return (const void*)seg->getActualLoadAddress();
-}
-
-uintptr_t ImageLoaderMachO::bindIndirectSymbol(uintptr_t* ptrToBind, const struct macho_section* sect, const char* symbolName, uintptr_t targetAddr, ImageLoader* targetImage, const LinkContext& context)
+const void* ImageLoaderMachO::getEnd() const
+{
+ uintptr_t lastAddress = 0;
+ for (ImageLoader::SegmentIterator it = this->beginSegments(); it != this->endSegments(); ++it ) {
+ Segment* seg = *it;
+ uintptr_t segEnd = seg->getActualLoadAddress(this) + seg->getSize();
+ if ( segEnd > lastAddress )
+ lastAddress = segEnd;
+ }
+ return (const void*)lastAddress;
+}
+
+uintptr_t ImageLoaderMachO::bindIndirectSymbol(uintptr_t* ptrToBind, const struct macho_section* sect, const char* symbolName, uintptr_t targetAddr, const ImageLoader* targetImage, const LinkContext& context)
{
if ( context.verboseBind ) {
const char* path = NULL;
if ( targetImage != NULL )
path = targetImage->getShortName();
- fprintf(stderr, "dyld: bind: %s:%s$%s = %s:%s, *0x%08lx = 0x%08lx\n",
+ dyld::log("dyld: bind: %s:%s$%s = %s:%s, *0x%08lx = 0x%08lx\n",
this->getShortName(), symbolName, (((sect->flags & SECTION_TYPE)==S_NON_LAZY_SYMBOL_POINTERS) ? "non_lazy_ptr" : "lazy_ptr"),
path, symbolName, (uintptr_t)ptrToBind, targetAddr);
}
@@ -1973,14 +2343,35 @@
#if __i386__
// i386 has special self-modifying stubs that change from "CALL rel32" to "JMP rel32"
if ( ((sect->flags & SECTION_TYPE) == S_SYMBOL_STUBS) && ((sect->flags & S_ATTR_SELF_MODIFYING_CODE) != 0) && (sect->reserved2 == 5) ) {
- uint8_t* const jmpTableEntryToPatch = (uint8_t*)ptrToBind;
uint32_t rel32 = targetAddr - (((uint32_t)ptrToBind)+5);
- //fprintf(stderr, "rewriting stub at %p\n", jmpTableEntryToPatch);
- jmpTableEntryToPatch[0] = 0xE9; // JMP rel32
- jmpTableEntryToPatch[1] = rel32 & 0xFF;
- jmpTableEntryToPatch[2] = (rel32 >> 8) & 0xFF;
- jmpTableEntryToPatch[3] = (rel32 >> 16) & 0xFF;
- jmpTableEntryToPatch[4] = (rel32 >> 24) & 0xFF;
+ // re-write instruction in a thread-safe manner
+ // use 8-byte compare-and-swap to alter 5-byte jump table entries
+ // loop is required in case the extra three bytes that cover the next entry are altered by another thread
+ bool done = false;
+ while ( !done ) {
+ volatile int64_t* jumpPtr = (int64_t*)ptrToBind;
+ int pad = 0;
+ // By default the three extra bytes swapped follow the 5-byte JMP.
+ // But, if the 5-byte jump is up against the end of the __IMPORT segment
+ // We don't want to access bytes off the end of the segment, so we shift
+ // the extra bytes to precede the 5-byte JMP.
+ if ( (((uint32_t)ptrToBind + 8) & 0x00000FFC) == 0x00000000 ) {
+ jumpPtr = (int64_t*)((uint32_t)ptrToBind - 3);
+ pad = 3;
+ }
+ int64_t oldEntry = *jumpPtr;
+ union {
+ int64_t int64;
+ uint8_t bytes[8];
+ } newEntry;
+ newEntry.int64 = oldEntry;
+ newEntry.bytes[pad+0] = 0xE9; // JMP rel32
+ newEntry.bytes[pad+1] = rel32 & 0xFF;
+ newEntry.bytes[pad+2] = (rel32 >> 8) & 0xFF;
+ newEntry.bytes[pad+3] = (rel32 >> 16) & 0xFF;
+ newEntry.bytes[pad+4] = (rel32 >> 24) & 0xFF;
+ done = OSAtomicCompareAndSwap64Barrier(oldEntry, newEntry.int64, (int64_t*)jumpPtr);
+ }
}
else
#endif
@@ -2033,10 +2424,16 @@
#endif
if ( symbolIndex != INDIRECT_SYMBOL_ABS && symbolIndex != INDIRECT_SYMBOL_LOCAL ) {
const char* symbolName = &fStrings[fSymbolTable[symbolIndex].n_un.n_strx];
- ImageLoader* image = NULL;
- uintptr_t symbolAddr = this->resolveUndefined(context, &fSymbolTable[symbolIndex], twoLevel, &image);
+ const ImageLoader* image = NULL;
+ uintptr_t symbolAddr = this->resolveUndefined(context, &fSymbolTable[symbolIndex], twoLevel, &image);
+ #if __i386__
+ this->makeImportSegmentWritable(context);
+ #endif
symbolAddr = this->bindIndirectSymbol(lazyPointer, sect, symbolName, symbolAddr, image, context);
++fgTotalLazyBindFixups;
+ #if __i386__
+ this->makeImportSegmentReadOnly(context);
+ #endif
return symbolAddr;
}
}
@@ -2045,14 +2442,57 @@
}
cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
}
- throw "lazy pointer not found";
-}
-
-
-
-
-void ImageLoaderMachO::doBindIndirectSymbolPointers(const LinkContext& context, BindingLaziness bindness, bool onlyCoalescedSymbols)
-{
+ dyld::throwf("lazy pointer not found at address %p in image %s", lazyPointer, this->getPath());
+}
+
+
+#if __i386__
+//
+// For security the __IMPORT segments in the shared cache are normally not writable.
+// Any image can also be linked with -read_only_stubs to make their __IMPORT segments normally not writable.
+// For these images, dyld must change the page protection before updating them.
+// The spin lock is required because lazy symbol binding is done without taking the global dyld lock.
+// It keeps only one __IMPORT segment writable at a time.
+// Pre-main(), the shared cache __IMPORT segments are always writable, so we don't need to change the protection.
+//
+void ImageLoaderMachO::makeImportSegmentWritable(const LinkContext& context)
+{
+ if ( fReadOnlyImportSegment != NULL ) {
+ if ( fInSharedCache ) {
+ if ( context.startedInitializingMainExecutable ) {
+ _spin_lock(&fgReadOnlyImportSpinLock);
+ context.makeSharedCacheImportSegmentsWritable(true);
+ }
+ }
+ else {
+ _spin_lock(&fgReadOnlyImportSpinLock);
+ fReadOnlyImportSegment->tempWritable(context, this);
+ }
+ }
+}
+
+void ImageLoaderMachO::makeImportSegmentReadOnly(const LinkContext& context)
+{
+ if ( fReadOnlyImportSegment != NULL ) {
+ if ( fInSharedCache ) {
+ if ( context.startedInitializingMainExecutable ) {
+ context.makeSharedCacheImportSegmentsWritable(false);
+ _spin_unlock(&fgReadOnlyImportSpinLock);
+ }
+ }
+ else {
+ fReadOnlyImportSegment->setPermissions(context, this);
+ _spin_unlock(&fgReadOnlyImportSpinLock);
+ }
+ }
+}
+#endif
+
+void ImageLoaderMachO::doBindIndirectSymbolPointers(const LinkContext& context, bool bindNonLazys, bool bindLazys, bool onlyCoalescedSymbols)
+{
+#if __i386__
+ this->makeImportSegmentWritable(context);
+#endif
// scan for all non-lazy-pointer sections
const bool twoLevel = this->usesTwoLevelNameSpace();
const uint32_t cmd_count = ((macho_header*)fMachOData)->ncmds;
@@ -2071,13 +2511,13 @@
uint32_t elementSize = sizeof(uintptr_t);
uint32_t elementCount = sect->size / elementSize;
if ( type == S_NON_LAZY_SYMBOL_POINTERS ) {
- if ( (bindness == kLazyOnly) || (bindness == kLazyOnlyNoDependents) )
+ if ( ! bindNonLazys )
continue;
}
else if ( type == S_LAZY_SYMBOL_POINTERS ) {
// process each symbol pointer in this section
fgTotalPossibleLazyBindFixups += elementCount;
- if ( bindness == kNonLazyOnly )
+ if ( ! bindLazys )
continue;
}
#if __i386__
@@ -2086,7 +2526,7 @@
elementCount = sect->size / 5;
elementSize = 5;
fgTotalPossibleLazyBindFixups += elementCount;
- if ( bindness == kNonLazyOnly )
+ if ( ! bindLazys )
continue;
}
#endif
@@ -2096,6 +2536,9 @@
const uint32_t indirectTableOffset = sect->reserved1;
uint8_t* ptrToBind = (uint8_t*)(sect->addr + fSlide);
for (uint32_t j=0; j < elementCount; ++j, ptrToBind += elementSize) {
+ #if LINKEDIT_USAGE_DEBUG
+ noteAccessedLinkEditAddress(&indirectTable[indirectTableOffset + j]);
+ #endif
uint32_t symbolIndex = indirectTable[indirectTableOffset + j];
if ( symbolIndex == INDIRECT_SYMBOL_LOCAL) {
*((uintptr_t*)ptrToBind) += this->fSlide;
@@ -2122,7 +2565,7 @@
// symbol table entry is an import entry (usually it is a local symbol
// definition).
if ( context.verboseWarnings && !alreadyWarned ) {
- fprintf(stderr, "dyld: malformed executable '%s', skipping indirect symbol to %s\n",
+ dyld::log("dyld: malformed executable '%s', skipping indirect symbol to %s\n",
this->getPath(), &fStrings[sym->n_un.n_strx]);
alreadyWarned = true;
}
@@ -2130,7 +2573,7 @@
}
}
}
- ImageLoader *image = NULL;
+ const ImageLoader* image = NULL;
// if only processing coalesced symbols and this one does not require coalesceing, skip to next
if ( onlyCoalescedSymbols && !symbolRequiresCoalescing(sym) )
continue;
@@ -2139,43 +2582,35 @@
// update pointer
symbolAddr = this->bindIndirectSymbol((uintptr_t*)ptrToBind, sect, &fStrings[sym->n_un.n_strx], symbolAddr, image, context);
+ // update stats
+ ++fgTotalBindFixups;
}
}
- // update stats
- fgTotalBindFixups += elementCount;
}
}
break;
}
cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
}
-}
-
-/*
- * The address of these symbols are written in to the (__DATA,__dyld) section
- * at the following offsets:
- * at offset 0 stub_binding_helper_interface
- * at offset 4 _dyld_func_lookup
- * at offset 8 start_debug_thread
- * The 'C' types (if any) for these symbols are ignored here and all are
- * declared as longs so the assignment of their address in to the section will
- * not require a cast. stub_binding_helper_interface is really a label in the
- * assembly code interface for the stub binding. It does not have a meaningful
- * 'C' type. _dyld_func_lookup is the routine in dyld_libfuncs.c.
- * start_debug_thread is the routine in debug.c.
- *
- * For ppc the image's stub_binding_binding_helper is read from:
- * at offset 20 the image's stub_binding_binding_helper address
- * and saved into to the image structure.
- */
+#if __i386__
+ this->makeImportSegmentReadOnly(context);
+#endif
+}
+
+#if SUPPORT_OLD_CRT_INITIALIZATION
+// first 16 bytes of "start" in crt1.o
+#if __ppc__
+ static uint32_t sStandardEntryPointInstructions[4] = { 0x7c3a0b78, 0x3821fffc, 0x54210034, 0x38000000 };
+#elif __i386__
+ static uint8_t sStandardEntryPointInstructions[16] = { 0x6a, 0x00, 0x89, 0xe5, 0x83, 0xe4, 0xf0, 0x83, 0xec, 0x10, 0x8b, 0x5d, 0x04, 0x89, 0x5c, 0x24 };
+#endif
+#endif
+
struct DATAdyld {
- void* dyldLazyBinder; // filled in at launch by dyld to point into dyld to &stub_binding_helper_interface
- void* dyldFuncLookup; // filled in at launch by dyld to point into dyld to &_dyld_func_lookup
- void* startDebugThread; // debugger interface ???
- void* debugPort; // debugger interface ???
- void* debugThread; // debugger interface ???
- void* stubBindHelper; // filled in at static link time to point to stub helper in image
- void* coreDebug; // ???
+ void* dyldLazyBinder; // filled in at launch by dyld to point into dyld to &stub_binding_helper_interface
+ void* dyldFuncLookup; // filled in at launch by dyld to point into dyld to &_dyld_func_lookup
+ // the following only exist in main executables built for 10.5 or later
+ ProgramVars vars;
};
// These are defined in dyldStartup.s
@@ -2186,29 +2621,68 @@
void ImageLoaderMachO::setupLazyPointerHandler(const LinkContext& context)
{
- if ( fDATAdyld != NULL ) {
- struct DATAdyld* dd = (struct DATAdyld*)(fDATAdyld->addr + fSlide);
- if ( fDATAdyld->size > offsetof(DATAdyld, dyldLazyBinder) ) {
- if ( dd->dyldLazyBinder != (void*)&stub_binding_helper )
- dd->dyldLazyBinder = (void*)&stub_binding_helper;
- }
- if ( fDATAdyld->size > offsetof(DATAdyld, dyldFuncLookup) ) {
- if ( dd->dyldFuncLookup != (void*)&dyld_func_lookup )
- dd->dyldFuncLookup = (void*)&dyld_func_lookup;
- }
- //if ( fDATAdyld->size > offsetof(DATAdyld, startDebugThread) )
- // dd->startDebugThread = &start_debug_thread;
-#ifdef __ppc__
- //if ( fDATAdyld->size > offsetof(DATAdyld, stubBindHelper) )
- // save = dd->stubBindHelper;
-#endif
+ 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;
+ // set up __dyld section
+ // optimizations:
+ // 1) do nothing if image is in dyld shared cache and dyld loaded at same address as when cache built
+ // 2) first read __dyld value, if already correct don't write, this prevents dirtying a page
+ if ( !fInSharedCache || !context.dyldLoadedAtSameAddressNeededBySharedCache ) {
+ 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;
+ if ( strcmp(seg->segname, "__DATA") == 0 ) {
+ 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) {
+ if ( strcmp(sect->sectname, "__dyld" ) == 0 ) {
+ struct DATAdyld* dd = (struct DATAdyld*)(sect->addr + fSlide);
+ if ( sect->size > offsetof(DATAdyld, dyldLazyBinder) ) {
+ if ( dd->dyldLazyBinder != (void*)&stub_binding_helper )
+ dd->dyldLazyBinder = (void*)&stub_binding_helper;
+ }
+ if ( sect->size > offsetof(DATAdyld, dyldFuncLookup) ) {
+ if ( dd->dyldFuncLookup != (void*)&dyld_func_lookup )
+ dd->dyldFuncLookup = (void*)&dyld_func_lookup;
+ }
+ if ( mh->filetype == MH_EXECUTE ) {
+ // there are two ways to get the program variables
+ if ( (sect->size > offsetof(DATAdyld, vars)) && (dd->vars.mh == mh) ) {
+ // some really old binaries have space for vars, but it is zero filled
+ // main executable has 10.5 style __dyld section that has program variable pointers
+ context.setNewProgramVars(dd->vars);
+ }
+ else {
+ // main executable is pre-10.5 and requires the symbols names to be looked up
+ this->lookupProgramVars(context);
+ #if SUPPORT_OLD_CRT_INITIALIZATION
+ // If the first 16 bytes of the entry point's instructions do not
+ // match what crt1.o supplies, then the program has a custom entry point.
+ // This means it might be doing something that needs to be executed before
+ // initializers are run.
+ if ( memcmp(this->getMain(), sStandardEntryPointInstructions, 16) != 0 ) {
+ if ( context.verboseInit )
+ dyld::log("dyld: program uses non-standard entry point so delaying running of initializers\n");
+ context.setRunInitialzersOldWay();
+ }
+ #endif
+ }
+ }
+ }
+ }
+ }
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
}
#if __i386__
- if ( ! this->usablePrebinding(context) || !this->usesTwoLevelNameSpace() ) {
+ if ( ! this->usablePrebinding(context) ) {
// reset all "fast" stubs
- 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;
+ this->makeImportSegmentWritable(context);
+ cmd = cmds;
for (uint32_t i = 0; i < cmd_count; ++i) {
switch (cmd->cmd) {
case LC_SEGMENT_COMMAND:
@@ -2220,16 +2694,49 @@
const uint8_t type = sect->flags & SECTION_TYPE;
if ( (type == S_SYMBOL_STUBS) && (sect->flags & S_ATTR_SELF_MODIFYING_CODE) && (sect->reserved2 == 5) ) {
// reset each jmp entry in this section
+ const uint32_t indirectTableOffset = sect->reserved1;
+ const uint32_t* const indirectTable = (uint32_t*)&fLinkEditBase[fDynamicInfo->indirectsymoff];
uint8_t* start = (uint8_t*)(sect->addr + this->fSlide);
uint8_t* end = start + sect->size;
uintptr_t dyldHandler = (uintptr_t)&fast_stub_binding_helper_interface;
- for (uint8_t* entry = start; entry < end; entry += 5) {
- uint32_t rel32 = dyldHandler - (((uint32_t)entry)+5);
- entry[0] = 0xE8; // CALL rel32
- entry[1] = rel32 & 0xFF;
- entry[2] = (rel32 >> 8) & 0xFF;
- entry[3] = (rel32 >> 16) & 0xFF;
- entry[4] = (rel32 >> 24) & 0xFF;
+ uint32_t entryIndex = 0;
+ for (uint8_t* entry = start; entry < end; entry += 5, ++entryIndex) {
+ bool installLazyHandler = true;
+ // jump table entries that cross a (64-byte) cache line boundary have the potential to cause crashes
+ // if the instruction is updated by one thread while being executed by another
+ if ( ((uint32_t)entry & 0xFFFFFFC0) != ((uint32_t)entry+4 & 0xFFFFFFC0) ) {
+ // need to bind this now to avoid a potential problem if bound lazily
+ uint32_t symbolIndex = indirectTable[indirectTableOffset + entryIndex];
+ // the latest linker marks 64-byte crossing stubs with INDIRECT_SYMBOL_ABS so they are not used
+ if ( symbolIndex != INDIRECT_SYMBOL_ABS ) {
+ const char* symbolName = &fStrings[fSymbolTable[symbolIndex].n_un.n_strx];
+ const ImageLoader* image = NULL;
+ try {
+ uintptr_t symbolAddr = this->resolveUndefined(context, &fSymbolTable[symbolIndex], this->usesTwoLevelNameSpace(), &image);
+ symbolAddr = this->bindIndirectSymbol((uintptr_t*)entry, sect, symbolName, symbolAddr, image, context);
+ ++fgTotalBindFixups;
+ uint32_t rel32 = symbolAddr - (((uint32_t)entry)+5);
+ entry[0] = 0xE9; // JMP rel32
+ entry[1] = rel32 & 0xFF;
+ entry[2] = (rel32 >> 8) & 0xFF;
+ entry[3] = (rel32 >> 16) & 0xFF;
+ entry[4] = (rel32 >> 24) & 0xFF;
+ installLazyHandler = false;
+ }
+ catch (const char* msg) {
+ // ignore errors when binding symbols early
+ // maybe the function is never called, and therefore erroring out now would be a regression
+ }
+ }
+ }
+ if ( installLazyHandler ) {
+ uint32_t rel32 = dyldHandler - (((uint32_t)entry)+5);
+ entry[0] = 0xE8; // CALL rel32
+ entry[1] = rel32 & 0xFF;
+ entry[2] = (rel32 >> 8) & 0xFF;
+ entry[3] = (rel32 >> 16) & 0xFF;
+ entry[4] = (rel32 >> 24) & 0xFF;
+ }
}
}
}
@@ -2237,14 +2744,51 @@
}
cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
}
- }
-#endif
-}
+ this->makeImportSegmentReadOnly(context);
+ }
+#endif
+}
+
+
+void ImageLoaderMachO::lookupProgramVars(const LinkContext& context) const
+{
+ ProgramVars vars = context.programVars;
+ const ImageLoader::Symbol* sym;
+
+ // get mach header directly
+ vars.mh = (macho_header*)fMachOData;
+
+ // lookup _NXArgc
+ sym = this->findExportedSymbol("_NXArgc", NULL, false, NULL);
+ if ( sym != NULL )
+ vars.NXArgcPtr = (int*)this->getExportedSymbolAddress(sym, context, this);
+
+ // lookup _NXArgv
+ sym = this->findExportedSymbol("_NXArgv", NULL, false, NULL);
+ if ( sym != NULL )
+ vars.NXArgvPtr = (const char***)this->getExportedSymbolAddress(sym, context, this);
+
+ // lookup _environ
+ sym = this->findExportedSymbol("_environ", NULL, false, NULL);
+ if ( sym != NULL )
+ vars.environPtr = (const char***)this->getExportedSymbolAddress(sym, context, this);
+
+ // lookup __progname
+ sym = this->findExportedSymbol("___progname", NULL, false, NULL);
+ if ( sym != NULL )
+ vars.__prognamePtr = (const char**)this->getExportedSymbolAddress(sym, context, this);
+
+ context.setNewProgramVars(vars);
+}
+
bool ImageLoaderMachO::usablePrebinding(const LinkContext& context) const
{
// if prebound and loaded at prebound address, and all libraries are same as when this was prebound, then no need to bind
- if ( this->isPrebindable() && this->allDependentLibrariesAsWhenPreBound() && (this->getSlide() == 0) ) {
+ if ( (this->isPrebindable() || fInSharedCache)
+ && (this->getSlide() == 0)
+ && this->usesTwoLevelNameSpace()
+ && this->allDependentLibrariesAsWhenPreBound() ) {
// allow environment variables to disable prebinding
if ( context.bindFlat )
return false;
@@ -2262,63 +2806,134 @@
return false;
}
-void ImageLoaderMachO::doBind(const LinkContext& context, BindingLaziness bindness)
+void ImageLoaderMachO::doBindJustLazies(const LinkContext& context)
+{
+ // some API called requested that all lazy pointers in this image be force bound
+ this->doBindIndirectSymbolPointers(context, false, true, false);
+}
+
+void ImageLoaderMachO::doBind(const LinkContext& context, bool forceLazysBound)
{
// set dyld entry points in image
this->setupLazyPointerHandler(context);
// if prebound and loaded at prebound address, and all libraries are same as when this was prebound, then no need to bind
- // note: flat-namespace binaries need to be imports rebound (even if correctly prebound)
- if ( this->usablePrebinding(context) && this->usesTwoLevelNameSpace() ) {
+ // note: flat-namespace binaries need to have imports rebound (even if correctly prebound)
+ if ( this->usablePrebinding(context) ) {
// if image has coalesced symbols, then these need to be rebound, unless this is the only image with weak symbols
if ( this->needsCoalescing() && (fgCountOfImagesWithWeakExports > 1) ) {
this->doBindExternalRelocations(context, true);
- this->doBindIndirectSymbolPointers(context, kLazyAndNonLazy, true);
- }
+ this->doBindIndirectSymbolPointers(context, true, true, true);
+ }
+ else {
+ ++fgImagesRequiringNoFixups;
+ }
+
// skip binding because prebound and prebinding not disabled
return;
}
- // values bound by name are stored two different ways in mach-o
- switch (bindness) {
- case kNonLazyOnly:
- case kLazyAndNonLazy:
- // external relocations are used for data initialized to external symbols
- this->doBindExternalRelocations(context, false);
- break;
- case kLazyOnly:
- case kLazyOnlyNoDependents:
- break;
- }
- // "indirect symbols" are used for code references to external symbols
- this->doBindIndirectSymbolPointers(context, bindness, false);
-}
-
-
+ // values bound by name are stored two different ways in mach-o:
+
+ // 1) external relocations are used for data initialized to external symbols
+ this->doBindExternalRelocations(context, false);
+
+ // 2) "indirect symbols" are used for code references to external symbols
+ // if this image is in the shared cache, there is noway to reset the lazy pointers, so bind them now
+ this->doBindIndirectSymbolPointers(context, true, forceLazysBound || fInSharedCache, false);
+}
+
+void ImageLoaderMachO::doUpdateMappingPermissions(const LinkContext& context)
+{
+#if __i386__
+ if ( (fReadOnlyImportSegment != NULL) && !fInSharedCache )
+ fReadOnlyImportSegment->setPermissions(context, this);
+#endif
+}
void ImageLoaderMachO::doImageInit(const LinkContext& context)
{
- if ( fDashInit != NULL ) {
- Initializer func = (Initializer)(fDashInit->init_address + fSlide);
- if ( context.verboseInit )
- fprintf(stderr, "dyld: calling -init function 0x%p in %s\n", func, this->getPath());
- func(context.argc, context.argv, context.envp, context.apple);
+ if ( fHasDashInit ) {
+ 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 (unsigned long i = 0; i < cmd_count; ++i) {
+ switch (cmd->cmd) {
+ case LC_ROUTINES_COMMAND:
+ Initializer func = (Initializer)(((struct macho_routines_command*)cmd)->init_address + fSlide);
+ if ( context.verboseInit )
+ dyld::log("dyld: calling -init function 0x%p in %s\n", func, this->getPath());
+ func(context.argc, context.argv, context.envp, context.apple, &context.programVars);
+ break;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
}
}
void ImageLoaderMachO::doModInitFunctions(const LinkContext& context)
{
- if ( fModInitSection != NULL ) {
- Initializer* inits = (Initializer*)(fModInitSection->addr + fSlide);
- const uint32_t count = fModInitSection->size / sizeof(uintptr_t);
- for (uint32_t i=0; i < count; ++i) {
- Initializer func = inits[i];
- if ( context.verboseInit )
- fprintf(stderr, "dyld: calling initializer function %p in %s\n", func, this->getPath());
- func(context.argc, context.argv, context.envp, context.apple);
- }
- }
-}
+ if ( fHasInitializers ) {
+ 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 (unsigned long 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_MOD_INIT_FUNC_POINTERS ) {
+ Initializer* inits = (Initializer*)(sect->addr + fSlide);
+ const uint32_t count = sect->size / sizeof(uintptr_t);
+ for (uint32_t i=0; i < count; ++i) {
+ Initializer func = inits[i];
+ if ( context.verboseInit )
+ dyld::log("dyld: calling initializer function %p in %s\n", func, this->getPath());
+ func(context.argc, context.argv, context.envp, context.apple, &context.programVars);
+ }
+ }
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ }
+ }
+}
+
+
+
+
+void ImageLoaderMachO::doGetDOFSections(const LinkContext& context, std::vector<ImageLoader::DOFInfo>& dofs)
+{
+ if ( fHasDOFSections ) {
+ // walk load commands (mapped in at start of __TEXT segment)
+ 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_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) {
+ if ( (sect->flags & SECTION_TYPE) == S_DTRACE_DOF ) {
+ ImageLoader::DOFInfo info;
+ info.dof = (void*)(sect->addr + fSlide);
+ info.imageHeader = this->machHeader();
+ info.imageShortName = this->getShortName();
+ dofs.push_back(info);
+ }
+ }
+ }
+ break;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ }
+}
void ImageLoaderMachO::doInitialization(const LinkContext& context)
@@ -2330,407 +2945,215 @@
bool ImageLoaderMachO::needsInitialization()
{
- return ( (fDashInit != NULL) || (fModInitSection != NULL) );
+ return ( fHasDashInit || fHasInitializers );
}
bool ImageLoaderMachO::needsTermination()
{
- return ( fModTermSection != NULL );
-}
-
+ return fHasTerminators;
+}
+
+#if IMAGE_NOTIFY_SUPPORT
bool ImageLoaderMachO::hasImageNotification()
{
- return ( fImageNotifySection != NULL );
-}
-
+ return fHasImageNotifySection;
+}
+#endif
void ImageLoaderMachO::doTermination(const LinkContext& context)
{
- if ( fModTermSection != NULL ) {
- Terminator* terms = (Terminator*)(fModTermSection->addr + fSlide);
- const uint32_t count = fModTermSection->size / sizeof(uintptr_t);
- for (uint32_t i=count; i > 0; --i) {
- Terminator func = terms[i-1];
- if ( context.verboseInit )
- fprintf(stderr, "dyld: calling terminaton function %p in %s\n", func, this->getPath());
- func();
- }
- }
-}
-
-void ImageLoaderMachO::doNotification(enum dyld_image_mode mode, uint32_t infoCount, const struct dyld_image_info info[])
-{
- if ( fImageNotifySection != NULL ) {
- dyld_image_notifier* notes = (dyld_image_notifier*)(fImageNotifySection->addr + fSlide);
- const uint32_t count = fImageNotifySection->size / sizeof(uintptr_t);
- for (uint32_t i=count; i > 0; --i) {
- dyld_image_notifier func = notes[i-1];
- func(mode, infoCount, info);
- }
- }
-}
-
-void ImageLoaderMachO::printStatistics(unsigned int imageCount)
-{
- ImageLoader::printStatistics(imageCount);
- fprintf(stderr, "total hinted binary tree searches: %d\n", fgHintedBinaryTreeSearchs);
- fprintf(stderr, "total unhinted binary tree searches: %d\n", fgUnhintedBinaryTreeSearchs);
- fprintf(stderr, "total images with weak exports: %d\n", fgCountOfImagesWithWeakExports);
-
-#if LINKEDIT_USAGE_DEBUG
- fprintf(stderr, "linkedit pages accessed (%lu):\n", sLinkEditPageBuckets.size());
-#endif
-}
-
-void ImageLoaderMachO::doPrebinding(const LinkContext& context, time_t timestamp, uint8_t* fileToPrebind)
-{
- // update __DATA segment
- this->applyPrebindingToDATA(fileToPrebind);
-
- // update load commands
- this->applyPrebindingToLoadCommands(context, fileToPrebind, timestamp);
-
- // update symbol table
- this->applyPrebindingToLinkEdit(context, fileToPrebind);
-}
-
-void ImageLoaderMachO::applyPrebindingToDATA(uint8_t* fileToPrebind)
-{
- const unsigned int segmentCount = fSegments.size();
- for(unsigned int i=0; i < segmentCount; ++i) {
- SegmentMachO* seg = (SegmentMachO*)fSegments[i];
- if ( seg->writeable() ) {
- memcpy(&fileToPrebind[seg->fFileOffset], (void*)seg->getActualLoadAddress(), seg->fFileSize);
- }
- }
-}
-
-void ImageLoaderMachO::applyPrebindingToLoadCommands(const LinkContext& context, uint8_t* fileToPrebind, time_t timestamp)
-{
- macho_header* mh = (macho_header*)fileToPrebind;
- const uint32_t cmd_count = mh->ncmds;
- const struct load_command* const cmds = (struct load_command*)&fileToPrebind[sizeof(macho_header)];
- const struct load_command* cmd = cmds;
- for (uint32_t i = 0; i < cmd_count; ++i) {
- switch (cmd->cmd) {
- case LC_LOAD_DYLIB:
- case LC_LOAD_WEAK_DYLIB:
- {
- // update each dylib load command with the timestamp of the target dylib
- struct dylib_command* dylib = (struct dylib_command*)cmd;
- const char* name = (char*)cmd + dylib->dylib.name.offset;
- for (const DependentLibrary* dl=fLibraries; dl < &fLibraries[fLibrariesCount]; dl++) {
- if (strcmp(dl->name, name) == 0 ) {
- // found matching DependentLibrary for this load command
- ImageLoaderMachO* targetImage = (ImageLoaderMachO*)(dl->image); // !!! assume only mach-o images are prebound
- if ( ! targetImage->isPrebindable() )
- throw "dependent dylib is not prebound";
- // if the target is currently being re-prebound then its timestamp will be the same as this one
- if ( ! targetImage->usablePrebinding(context) ) {
- dylib->dylib.timestamp = timestamp;
- }
- else {
- // otherwise dependent library is already correctly prebound, so use its checksum
- dylib->dylib.timestamp = targetImage->doGetLibraryInfo().checksum;
- }
- break;
+ if ( fHasTerminators ) {
+ 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 (unsigned long 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_MOD_TERM_FUNC_POINTERS ) {
+ Terminator* terms = (Terminator*)(sect->addr + fSlide);
+ const uint32_t count = sect->size / sizeof(uintptr_t);
+ for (uint32_t i=count; i > 0; --i) {
+ Terminator func = terms[i-1];
+ if ( context.verboseInit )
+ dyld::log("dyld: calling terminaton function %p in %s\n", func, this->getPath());
+ func();
}
}
}
- break;
- case LC_ID_DYLIB:
- {
- // update the ID of this library with the new timestamp
- struct dylib_command* dylib = (struct dylib_command*)cmd;
- dylib->dylib.timestamp = timestamp;
- }
- break;
- case LC_SEGMENT_COMMAND:
- // if dylib was rebased, update segment commands
- if ( fSlide != 0 ) {
- struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
- seg->vmaddr += fSlide;
- struct macho_section* const sectionsStart = (struct macho_section*)((char*)seg + sizeof(struct macho_segment_command));
- struct macho_section* const sectionsEnd = §ionsStart[seg->nsects];
- for (struct macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
- sect->addr += fSlide;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ }
+}
+
+#if IMAGE_NOTIFY_SUPPORT
+void ImageLoaderMachO::doNotification(enum dyld_image_mode mode, uint32_t infoCount, const struct dyld_image_info info[])
+{
+ if ( fHasImageNotifySection ) {
+ 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 (unsigned long i = 0; i < cmd_count; ++i) {
+ if ( cmd->cmd == LC_SEGMENT_COMMAND ) {
+ const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
+ if ( strcmp(seg->segname, "__DATA") == 0 ) {
+ 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) {
+ if ( strcmp(sect->sectname, "__image_notify") == 0 ) {
+ dyld_image_notifier* notes = (dyld_image_notifier*)(sect->addr + fSlide);
+ const uint32_t count = sect->size / sizeof(uintptr_t);
+ for (uint32_t i=count; i > 0; --i) {
+ dyld_image_notifier func = notes[i-1];
+ func(mode, infoCount, info);
+ }
+ }
}
}
- break;
- case LC_ROUTINES_COMMAND:
- // if dylib was rebased, update -init command
- if ( fSlide != 0 ) {
- struct macho_routines_command* routines = (struct macho_routines_command*)cmd;
- routines->init_address += fSlide;
- }
- break;
- }
- cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
- }
-}
-
-void ImageLoaderMachO::applyPrebindingToLinkEdit(const LinkContext& context, uint8_t* fileToPrebind)
-{
- // In prebound images, the n_value of the symbol table entry for is the prebound address
- // This is needed when prebinding can't be used, to back solve for any possible addend in non-lazy pointers
- const char* stringPool = NULL;
- struct macho_nlist* symbolTable = NULL;
- const struct dysymtab_command* dysymtab = NULL;
-
- // get symbol table info
- macho_header* mh = (macho_header*)fileToPrebind;
- const uint32_t cmd_count = mh->ncmds;
- const struct load_command* const cmds = (struct load_command*)&fileToPrebind[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;
- stringPool = (const char*)&fileToPrebind[symtab->stroff];
- symbolTable = (struct macho_nlist*)(&fileToPrebind[symtab->symoff]);
- }
- break;
- case LC_DYSYMTAB:
- dysymtab = (struct dysymtab_command*)cmd;
- break;
- }
- cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
- }
-
- // walk all imports and re-resolve their n_value (needed incase prebinding is invalid)
- struct macho_nlist* lastImport = &symbolTable[dysymtab->iundefsym+dysymtab->nundefsym];
- for (struct macho_nlist* entry = &symbolTable[dysymtab->iundefsym]; entry < lastImport; ++entry) {
- ImageLoader* dummy;
- entry->n_value = this->resolveUndefined(context, entry, this->usesTwoLevelNameSpace(), &dummy);
- }
-
- // walk all exports and slide their n_value
- struct macho_nlist* lastExport = &symbolTable[dysymtab->iextdefsym+dysymtab->nextdefsym];
- for (struct macho_nlist* entry = &symbolTable[dysymtab->iextdefsym]; entry < lastExport; ++entry) {
- if ( (entry->n_type & N_TYPE) == N_SECT )
- entry->n_value += fSlide;
- }
-
- // walk all local symbols and slide their n_value
- struct macho_nlist* lastLocal = &symbolTable[dysymtab->ilocalsym+dysymtab->nlocalsym];
- for (struct macho_nlist* entry = &symbolTable[dysymtab->ilocalsym]; entry < lastLocal; ++entry) {
- if ( entry->n_sect != NO_SECT )
- entry->n_value += fSlide;
- }
-
- // walk all local relocations and reset every PPC_RELOC_PB_LA_PTR r_value
- relocation_info* const relocsStart = (struct relocation_info*)(&fileToPrebind[dysymtab->locreloff]);
- relocation_info* const relocsEnd = &relocsStart[dysymtab->nlocrel];
- for (relocation_info* reloc=relocsStart; reloc < relocsEnd; ++reloc) {
- if ( (reloc->r_address & R_SCATTERED) != 0 ) {
- struct scattered_relocation_info* sreloc = (struct scattered_relocation_info*)reloc;
- if (sreloc->r_length == RELOC_SIZE) {
- switch(sreloc->r_type) {
- #if __ppc__ || __ppc64__
- case PPC_RELOC_PB_LA_PTR:
- #elif __i386__
- case GENERIC_RELOC_PB_LA_PTR:
- #else
- #error unknown architecture
- #endif
- sreloc->r_value += fSlide;
- break;
- }
- }
- }
- }
-
- // if multi-module, fix up objc_addr (10.4 and later runtime does not use this, but we want to keep file checksum consistent)
- if ( dysymtab->nmodtab != 0 ) {
- dylib_module* const modulesStart = (struct dylib_module*)(&fileToPrebind[dysymtab->modtaboff]);
- dylib_module* const modulesEnd = &modulesStart[dysymtab->nmodtab];
- for (dylib_module* module=modulesStart; module < modulesEnd; ++module) {
- if ( module->objc_module_info_size != 0 ) {
- module->objc_module_info_addr += fSlide;
- }
- }
- }
-}
-
-// file on disk has been reprebound, but we are still mapped to old file
-void ImageLoaderMachO::prebindUnmap(const LinkContext& context)
-{
- // this removes all mappings to the old file, so the kernel will unlink (delete) it.
- // We need to leave the load commands and __LINKEDIT in place
- for (std::vector<class Segment*>::iterator it=fSegments.begin(); it != fSegments.end(); ++it) {
- void* segmentAddress = (void*)((*it)->getActualLoadAddress());
- uintptr_t segmentSize = (*it)->getSize();
- //fprintf(stderr, "unmapping segment %s at %p for %s\n", (*it)->getName(), segmentAddress, this->getPath());
- // save load commands at beginning of __TEXT segment
- if ( segmentAddress == fMachOData ) {
- // typically load commands are one or two pages in size, so ok to alloc on stack
- uint32_t loadCmdSize = sizeof(macho_header) + ((macho_header*)fMachOData)->sizeofcmds;
- uint32_t loadCmdPages = (loadCmdSize+4095) & (-4096);
- uint8_t loadcommands[loadCmdPages];
- memcpy(loadcommands, fMachOData, loadCmdPages);
- // unmap whole __TEXT segment
- munmap((void*)(fMachOData), segmentSize);
- // allocate and copy back mach_header and load commands
- vm_address_t addr = (vm_address_t)fMachOData;
- int r2 = vm_allocate(mach_task_self(), &addr, loadCmdPages, false /*at this address*/);
- if ( r2 != 0 )
- fprintf(stderr, "prebindUnmap() vm_allocate for __TEXT %d failed\n", loadCmdPages);
- memcpy((void*)fMachOData, loadcommands, loadCmdPages);
- //fprintf(stderr, "copying back load commands to %p size=%u for %s\n", segmentAddress, loadCmdPages, this->getPath());
- }
- else if ( strcmp((*it)->getName(), "__LINKEDIT") == 0 ) {
- uint32_t linkEditSize = segmentSize;
- uint32_t linkEditPages = (linkEditSize+4095) & (-4096);
- void* linkEditTmp = malloc(linkEditPages);
- memcpy(linkEditTmp, segmentAddress, linkEditPages);
- // unmap whole __LINKEDIT segment
- munmap(segmentAddress, segmentSize);
- vm_address_t addr = (vm_address_t)segmentAddress;
- int r2 = vm_allocate(mach_task_self(), &addr, linkEditPages, false /*at this address*/);
- if ( r2 != 0 )
- fprintf(stderr, "prebindUnmap() vm_allocate for __LINKEDIT %d failed\n", linkEditPages);
- memcpy(segmentAddress, linkEditTmp, linkEditPages);
- //fprintf(stderr, "copying back __LINKEDIT to %p size=%u for %s\n", segmentAddress, linkEditPages, this->getPath());
- free(linkEditTmp);
- }
- else {
- // unmap any other segment
- munmap((void*)(segmentAddress), (*it)->getSize());
- }
- }
-}
-
-
-
-SegmentMachO::SegmentMachO(const struct macho_segment_command* cmd, ImageLoaderMachO* image, const uint8_t* fileData)
- : fImage(image), fSize(cmd->vmsize), fFileSize(cmd->filesize), fFileOffset(cmd->fileoff), fPreferredLoadAddress(cmd->vmaddr),
- fVMProtection(cmd->initprot), fHasFixUps(false), fUnMapOnDestruction(false)
-{
- strncpy(fName, cmd->segname, 16);
- fName[16] = '\0';
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ }
+}
+#endif
+
+void ImageLoaderMachO::printStatistics(unsigned int imageCount)
+{
+ ImageLoader::printStatistics(imageCount);
+ //dyld::log("total hinted binary tree searches: %d\n", fgHintedBinaryTreeSearchs);
+ //dyld::log("total unhinted binary tree searches: %d\n", fgUnhintedBinaryTreeSearchs);
+ dyld::log("total images with weak exports: %d\n", fgCountOfImagesWithWeakExports);
+
+#if LINKEDIT_USAGE_DEBUG
+ dyld::log("linkedit pages accessed (%lu):\n", sLinkEditPageBuckets.size());
+#endif
+}
+
+
+ImageLoader::SegmentIterator ImageLoaderMachO::beginSegments() const
+{
+ return SegmentIterator(fSegmentsArray);
+}
+
+ImageLoader::SegmentIterator ImageLoaderMachO::endSegments() const
+{
+ return SegmentIterator(&fSegmentsArray[fSegmentsArrayCount]);
+}
+
+SegmentMachO::SegmentMachO(const struct macho_segment_command* cmd)
+ : fSegmentLoadCommand(cmd)
+{
+}
+
+SegmentMachO::~SegmentMachO()
+{
+}
+
+void SegmentMachO::adjust(const struct macho_segment_command* cmd)
+{
+ fSegmentLoadCommand = cmd;
+}
+
+void SegmentMachO::unmap(const ImageLoader* image)
+{
+ // update stats
+ --ImageLoader::fgTotalSegmentsMapped;
+ ImageLoader::fgTotalBytesMapped -= fSegmentLoadCommand->vmsize;
+ munmap((void*)(this->getActualLoadAddress(image)), fSegmentLoadCommand->vmsize);
+}
+
+
+const char* SegmentMachO::getName()
+{
+ return fSegmentLoadCommand->segname;
+}
+
+uintptr_t SegmentMachO::getSize()
+{
+ return fSegmentLoadCommand->vmsize;
+}
+
+uintptr_t SegmentMachO::getFileSize()
+{
+ return fSegmentLoadCommand->filesize;
+}
+
+uintptr_t SegmentMachO::getFileOffset()
+{
+ return fSegmentLoadCommand->fileoff;
+}
+
+bool SegmentMachO::readable()
+{
+ return ( (fSegmentLoadCommand->initprot & VM_PROT_READ) != 0);
+}
+
+bool SegmentMachO::writeable()
+{
+ return ((fSegmentLoadCommand->initprot & VM_PROT_WRITE) != 0);
+}
+
+bool SegmentMachO::executable()
+{
+ return ((fSegmentLoadCommand->initprot & VM_PROT_EXECUTE) != 0);
+}
+
+bool SegmentMachO::unaccessible()
+{
+ return (fSegmentLoadCommand->initprot == 0);
+}
+
+#if TEXT_RELOC_SUPPORT
+bool SegmentMachO::hasFixUps()
+{
// scan sections for fix-up bit
- const struct macho_section* const sectionsStart = (struct macho_section*)((char*)cmd + sizeof(struct macho_segment_command));
- const struct macho_section* const sectionsEnd = §ionsStart[cmd->nsects];
+ const struct macho_section* const sectionsStart = (struct macho_section*)((char*)fSegmentLoadCommand + sizeof(struct macho_segment_command));
+ const struct macho_section* const sectionsEnd = §ionsStart[fSegmentLoadCommand->nsects];
for (const struct macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
if ( (sect->flags & (S_ATTR_EXT_RELOC | S_ATTR_LOC_RELOC)) != 0 )
- fHasFixUps = true;
- }
-}
-
-SegmentMachO::~SegmentMachO()
-{
- if ( fUnMapOnDestruction ) {
- //fprintf(stderr, "unmapping segment %s at 0x%08lX\n", getName(), getActualLoadAddress());
- munmap((void*)(this->getActualLoadAddress()), this->getSize());
- }
-}
-
-const ImageLoader* SegmentMachO::getImage()
-{
- return fImage;
-}
-
-const char* SegmentMachO::getName()
-{
- return fName;
-}
-
-uintptr_t SegmentMachO::getSize()
-{
- return fSize;
-}
-
-uintptr_t SegmentMachO::getFileSize()
-{
- return fFileSize;
-}
-
-uintptr_t SegmentMachO::getFileOffset()
-{
- return fFileOffset;
-}
-
-bool SegmentMachO::readable()
-{
- return ( (fVMProtection & VM_PROT_READ) != 0);
-}
-
-bool SegmentMachO::writeable()
-{
- return ((fVMProtection & VM_PROT_WRITE) != 0);
-}
-
-bool SegmentMachO::executable()
-{
- return ((fVMProtection & VM_PROT_EXECUTE) != 0);
-}
-
-bool SegmentMachO::unaccessible()
-{
- return (fVMProtection == 0);
-}
-
-bool SegmentMachO::hasFixUps()
-{
- return fHasFixUps;
-}
-
-uintptr_t SegmentMachO::getActualLoadAddress()
-{
- return fPreferredLoadAddress + fImage->fSlide;
+ return true;
+ }
+ return false;
+}
+#endif
+
+#if __i386__
+bool SegmentMachO::readOnlyImportStubs()
+{
+ return ( (fSegmentLoadCommand->initprot & VM_PROT_EXECUTE)
+ && ((fSegmentLoadCommand->initprot & VM_PROT_WRITE) == 0)
+ && (strcmp(fSegmentLoadCommand->segname, "__IMPORT") == 0) );
+}
+#endif
+
+uintptr_t SegmentMachO::getActualLoadAddress(const ImageLoader* inImage)
+{
+ return fSegmentLoadCommand->vmaddr + inImage->getSlide();
}
uintptr_t SegmentMachO::getPreferredLoadAddress()
{
- return fPreferredLoadAddress;
+ return fSegmentLoadCommand->vmaddr;
}
bool SegmentMachO::hasPreferredLoadAddress()
{
- return (fPreferredLoadAddress != 0);
-}
-
-void SegmentMachO::setUnMapWhenDestructed(bool unmap)
-{
- fUnMapOnDestruction = unmap;
-}
-
-static uint32_t *buildCRCTable(void)
-{
- uint32_t *table = new uint32_t[256];
- uint32_t p = 0xedb88320UL; // standard CRC-32 polynomial
-
- for (unsigned int i = 0; i < 256; i++) {
- uint32_t c = i;
- for (unsigned int j = 0; j < 8; j++) {
- if ( c & 1 ) c = p ^ (c >> 1);
- else c = c >> 1;
- }
- table[i] = c;
- }
-
- return table;
-}
-
-uint32_t SegmentMachO::crc32()
-{
- if ( !readable() ) return 0;
-
- static uint32_t *crcTable = NULL;
- if ( !crcTable ) crcTable = buildCRCTable();
-
- uint32_t crc = ~(uint32_t)0;
- uint8_t *p = (uint8_t *)getActualLoadAddress();
- uint8_t *end = p + getSize();
- while ( p < end ) {
- crc = crcTable[(crc & 0xff) ^ (*p++)] ^ (crc >> 8);
- }
- return crc ^ ~(uint32_t)0;
-}
-
-
-
-
-
+ return (fSegmentLoadCommand->vmaddr != 0);
+}
+
+
+Segment* SegmentMachO::next(Segment* location)
+{
+ return &((SegmentMachO*)location)[1];
+}
+
+
+
+
+
+