Loading...
--- /dev/null
+++ dyld/dyld-655.1/dyld3/Loading.cpp
@@ -0,0 +1,875 @@
+/*
+ * Copyright (c) 2017 Apple Inc. All rights reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_LICENSE_HEADER_END@
+ */
+
+
+#include <bitset>
+
+#include <stdint.h>
+#include <string.h>
+#include <assert.h>
+#include <uuid/uuid.h>
+#include <mach/mach.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/sysctl.h>
+#include <fcntl.h>
+#include <sys/dtrace.h>
+#include <sys/errno.h>
+#include <unistd.h>
+#include <System/sys/mman.h>
+#include <System/sys/csr.h>
+#include <System/machine/cpu_capabilities.h>
+#include <bootstrap.h>
+#include <CommonCrypto/CommonDigest.h>
+#include <sandbox.h>
+#include <sandbox/private.h>
+#include <dispatch/dispatch.h>
+#include <mach/vm_page_size.h>
+
+#include "MachOFile.h"
+#include "MachOLoaded.h"
+#include "Logging.h"
+#include "Loading.h"
+#include "Tracing.h"
+#include "dyld.h"
+#include "dyld_cache_format.h"
+
+
+namespace dyld {
+ void log(const char* m, ...);
+}
+
+
+namespace {
+
+// utility to track a set of ImageNum's in use
+class VIS_HIDDEN ImageNumSet
+{
+public:
+ void add(dyld3::closure::ImageNum num);
+ bool contains(dyld3::closure::ImageNum num) const;
+
+private:
+ std::bitset<5120> _bitmap;
+ dyld3::OverflowSafeArray<dyld3::closure::ImageNum> _overflowArray;
+};
+
+void ImageNumSet::add(dyld3::closure::ImageNum num)
+{
+ if ( num < 5120 )
+ _bitmap.set(num);
+ else
+ _overflowArray.push_back(num);
+}
+
+bool ImageNumSet::contains(dyld3::closure::ImageNum num) const
+{
+ if ( num < 5120 )
+ return _bitmap.test(num);
+
+ for (dyld3::closure::ImageNum existingNum : _overflowArray) {
+ if ( existingNum == num )
+ return true;
+ }
+ return false;
+}
+} // namespace anonymous
+
+
+namespace dyld3 {
+
+Loader::Loader(Array<LoadedImage>& storage, const void* cacheAddress, const Array<const dyld3::closure::ImageArray*>& imagesArrays,
+ LogFunc logLoads, LogFunc logSegments, LogFunc logFixups, LogFunc logDofs)
+ : _allImages(storage), _imagesArrays(imagesArrays), _dyldCacheAddress(cacheAddress),
+ _logLoads(logLoads), _logSegments(logSegments), _logFixups(logFixups), _logDofs(logDofs)
+{
+}
+
+void Loader::addImage(const LoadedImage& li)
+{
+ _allImages.push_back(li);
+}
+
+LoadedImage* Loader::findImage(closure::ImageNum targetImageNum)
+{
+ for (LoadedImage& info : _allImages) {
+ if ( info.image()->representsImageNum(targetImageNum) )
+ return &info;
+ }
+ return nullptr;
+}
+
+uintptr_t Loader::resolveTarget(closure::Image::ResolvedSymbolTarget target)
+{
+ const LoadedImage* info;
+ switch ( target.sharedCache.kind ) {
+ case closure::Image::ResolvedSymbolTarget::kindSharedCache:
+ assert(_dyldCacheAddress != nullptr);
+ return (uintptr_t)_dyldCacheAddress + (uintptr_t)target.sharedCache.offset;
+
+ case closure::Image::ResolvedSymbolTarget::kindImage:
+ info = findImage(target.image.imageNum);
+ assert(info != nullptr);
+ return (uintptr_t)(info->loadedAddress()) + (uintptr_t)target.image.offset;
+
+ case closure::Image::ResolvedSymbolTarget::kindAbsolute:
+ if ( target.absolute.value & (1ULL << 62) )
+ return (uintptr_t)(target.absolute.value | 0xC000000000000000ULL);
+ else
+ return (uintptr_t)target.absolute.value;
+ }
+ assert(0 && "malformed ResolvedSymbolTarget");
+ return 0;
+}
+
+
+void Loader::completeAllDependents(Diagnostics& diag, uintptr_t topIndex)
+{
+ // accumulate all image overrides
+ STACK_ALLOC_ARRAY(ImageOverride, overrides, _allImages.maxCount());
+ for (const auto anArray : _imagesArrays) {
+ // ignore prebuilt Image* in dyld cache
+ if ( anArray->startImageNum() < dyld3::closure::kFirstLaunchClosureImageNum )
+ continue;
+ anArray->forEachImage(^(const dyld3::closure::Image* image, bool& stop) {
+ ImageOverride overrideEntry;
+ if ( image->isOverrideOfDyldCacheImage(overrideEntry.inCache) ) {
+ overrideEntry.replacement = image->imageNum();
+ overrides.push_back(overrideEntry);
+ }
+ });
+ }
+
+ // make cache for fast lookup of already loaded images
+ __block ImageNumSet alreadyLoaded;
+ for (int i=0; i <= topIndex; ++i) {
+ alreadyLoaded.add(_allImages[i].image()->imageNum());
+ }
+
+ // for each image in _allImages, starting at topIndex, make sure its depenents are in _allImages
+ uintptr_t index = topIndex;
+ while ( (index < _allImages.count()) && diag.noError() ) {
+ const closure::Image* image = _allImages[index].image();
+ //fprintf(stderr, "completeAllDependents(): looking at dependents of %s\n", image->path());
+ image->forEachDependentImage(^(uint32_t depIndex, closure::Image::LinkKind kind, closure::ImageNum depImageNum, bool& stop) {
+ // check if imageNum needs to be changed to an override
+ for (const ImageOverride& entry : overrides) {
+ if ( entry.inCache == depImageNum ) {
+ depImageNum = entry.replacement;
+ break;
+ }
+ }
+ // check if this dependent is already loaded
+ if ( !alreadyLoaded.contains(depImageNum) ) {
+ // if not, look in imagesArrays
+ const closure::Image* depImage = closure::ImageArray::findImage(_imagesArrays, depImageNum);
+ if ( depImage != nullptr ) {
+ //dyld::log(" load imageNum=0x%05X, image path=%s\n", depImageNum, depImage->path());
+ if ( _allImages.freeCount() == 0 ) {
+ diag.error("too many initial images");
+ stop = true;
+ }
+ else {
+ _allImages.push_back(LoadedImage::make(depImage));
+ }
+ alreadyLoaded.add(depImageNum);
+ }
+ else {
+ diag.error("unable to locate imageNum=0x%04X, depIndex=%d of %s", depImageNum, depIndex, image->path());
+ stop = true;
+ }
+ }
+ });
+ ++index;
+ }
+}
+
+void Loader::mapAndFixupAllImages(Diagnostics& diag, bool processDOFs, bool fromOFI, uintptr_t topIndex)
+{
+ // scan array and map images not already loaded
+ for (uintptr_t i=topIndex; i < _allImages.count(); ++i) {
+ LoadedImage& info = _allImages[i];
+ if ( info.loadedAddress() != nullptr ) {
+ // log main executable's segments
+ if ( (info.loadedAddress()->filetype == MH_EXECUTE) && (info.state() == LoadedImage::State::mapped) ) {
+ if ( _logSegments("dyld: mapped by kernel %s\n", info.image()->path()) ) {
+ info.image()->forEachDiskSegment(^(uint32_t segIndex, uint32_t fileOffset, uint32_t fileSize, int64_t vmOffset, uint64_t vmSize, uint8_t permissions, bool& stop) {
+ uint64_t start = (long)info.loadedAddress() + vmOffset;
+ uint64_t end = start+vmSize-1;
+ if ( (segIndex == 0) && (permissions == 0) ) {
+ start = 0;
+ }
+ _logSegments("%14s (%c%c%c) 0x%012llX->0x%012llX \n", info.loadedAddress()->segmentName(segIndex),
+ (permissions & PROT_READ) ? 'r' : '.', (permissions & PROT_WRITE) ? 'w' : '.', (permissions & PROT_EXEC) ? 'x' : '.' ,
+ start, end);
+ });
+ }
+ }
+ // skip over ones already loaded
+ continue;
+ }
+ if ( info.image()->inDyldCache() ) {
+ if ( info.image()->overridableDylib() ) {
+ struct stat statBuf;
+ if ( stat(info.image()->path(), &statBuf) == 0 ) {
+ // verify file has not changed since closure was built
+ uint64_t inode;
+ uint64_t mtime;
+ if ( info.image()->hasFileModTimeAndInode(inode, mtime) ) {
+ if ( (statBuf.st_mtime != mtime) || (statBuf.st_ino != inode) ) {
+ diag.error("dylib file mtime/inode changed since closure was built for '%s'", info.image()->path());
+ }
+ }
+ else {
+ diag.error("dylib file not expected on disk, must be a root '%s'", info.image()->path());
+ }
+ }
+ else if ( (_dyldCacheAddress != nullptr) && ((dyld_cache_header*)_dyldCacheAddress)->dylibsExpectedOnDisk ) {
+ diag.error("dylib file missing, was in dyld shared cache '%s'", info.image()->path());
+ }
+ }
+ if ( diag.noError() ) {
+ info.setLoadedAddress((MachOLoaded*)((uintptr_t)_dyldCacheAddress + info.image()->cacheOffset()));
+ info.setState(LoadedImage::State::fixedUp);
+ if ( _logSegments("dyld: Using from dyld cache %s\n", info.image()->path()) ) {
+ info.image()->forEachCacheSegment(^(uint32_t segIndex, uint64_t vmOffset, uint64_t vmSize, uint8_t permissions, bool &stop) {
+ _logSegments("%14s (%c%c%c) 0x%012lX->0x%012lX \n", info.loadedAddress()->segmentName(segIndex),
+ (permissions & PROT_READ) ? 'r' : '.', (permissions & PROT_WRITE) ? 'w' : '.', (permissions & PROT_EXEC) ? 'x' : '.' ,
+ (long)info.loadedAddress()+(long)vmOffset, (long)info.loadedAddress()+(long)vmOffset+(long)vmSize-1);
+ });
+ }
+ }
+ }
+ else {
+ mapImage(diag, info, fromOFI);
+ if ( diag.hasError() )
+ break; // out of for loop
+ }
+
+ }
+ if ( diag.hasError() ) {
+ // bummer, need to clean up by unmapping any images just mapped
+ for (LoadedImage& info : _allImages) {
+ if ( (info.state() == LoadedImage::State::mapped) && !info.image()->inDyldCache() && !info.leaveMapped() ) {
+ _logSegments("dyld: unmapping %s\n", info.image()->path());
+ unmapImage(info);
+ }
+ }
+ return;
+ }
+
+ // apply fixups
+ for (uintptr_t i=topIndex; i < _allImages.count(); ++i) {
+ LoadedImage& info = _allImages[i];
+ // images in shared cache do not need fixups applied
+ if ( info.image()->inDyldCache() )
+ continue;
+ // previously loaded images were previously fixed up
+ if ( info.state() < LoadedImage::State::fixedUp ) {
+ applyFixupsToImage(diag, info);
+ if ( diag.hasError() )
+ break;
+ info.setState(LoadedImage::State::fixedUp);
+ }
+ }
+
+ // find and register dtrace DOFs
+ if ( processDOFs ) {
+ STACK_ALLOC_OVERFLOW_SAFE_ARRAY(DOFInfo, dofImages, _allImages.count());
+ for (uintptr_t i=topIndex; i < _allImages.count(); ++i) {
+ LoadedImage& info = _allImages[i];
+ info.image()->forEachDOF(info.loadedAddress(), ^(const void* section) {
+ DOFInfo dofInfo;
+ dofInfo.dof = section;
+ dofInfo.imageHeader = info.loadedAddress();
+ dofInfo.imageShortName = info.image()->leafName();
+ dofImages.push_back(dofInfo);
+ });
+ }
+ registerDOFs(dofImages);
+ }
+}
+
+bool Loader::sandboxBlocked(const char* path, const char* kind)
+{
+#if TARGET_IPHONE_SIMULATOR
+ // sandbox calls not yet supported in dyld_sim
+ return false;
+#else
+ sandbox_filter_type filter = (sandbox_filter_type)(SANDBOX_FILTER_PATH | SANDBOX_CHECK_NO_REPORT);
+ return ( sandbox_check(getpid(), kind, filter, path) > 0 );
+#endif
+}
+
+bool Loader::sandboxBlockedMmap(const char* path)
+{
+ return sandboxBlocked(path, "file-map-executable");
+}
+
+bool Loader::sandboxBlockedOpen(const char* path)
+{
+ return sandboxBlocked(path, "file-read-data");
+}
+
+bool Loader::sandboxBlockedStat(const char* path)
+{
+ return sandboxBlocked(path, "file-read-metadata");
+}
+
+void Loader::mapImage(Diagnostics& diag, LoadedImage& info, bool fromOFI)
+{
+ dyld3::ScopedTimer timer(DBG_DYLD_TIMING_MAP_IMAGE, info.image()->path(), 0, 0);
+
+ const closure::Image* image = info.image();
+ uint64_t sliceOffset = image->sliceOffsetInFile();
+ const uint64_t totalVMSize = image->vmSizeToMap();
+ uint32_t codeSignFileOffset;
+ uint32_t codeSignFileSize;
+ bool isCodeSigned = image->hasCodeSignature(codeSignFileOffset, codeSignFileSize);
+
+ // open file
+ int fd = ::open(info.image()->path(), O_RDONLY, 0);
+ if ( fd == -1 ) {
+ int openErr = errno;
+ if ( (openErr == EPERM) && sandboxBlockedOpen(image->path()) )
+ diag.error("file system sandbox blocked open(\"%s\", O_RDONLY)", image->path());
+ else
+ diag.error("open(\"%s\", O_RDONLY) failed with errno=%d", image->path(), openErr);
+ return;
+ }
+
+ // get file info
+ struct stat statBuf;
+#if TARGET_IPHONE_SIMULATOR
+ if ( stat(image->path(), &statBuf) != 0 ) {
+#else
+ if ( fstat(fd, &statBuf) != 0 ) {
+#endif
+ int statErr = errno;
+ if ( (statErr == EPERM) && sandboxBlockedStat(image->path()) )
+ diag.error("file system sandbox blocked stat(\"%s\")", image->path());
+ else
+ diag.error("stat(\"%s\") failed with errno=%d", image->path(), statErr);
+ close(fd);
+ return;
+ }
+
+ // verify file has not changed since closure was built
+ uint64_t inode;
+ uint64_t mtime;
+ if ( image->hasFileModTimeAndInode(inode, mtime) ) {
+ if ( (statBuf.st_mtime != mtime) || (statBuf.st_ino != inode) ) {
+ diag.error("file mtime/inode changed since closure was built for '%s'", image->path());
+ close(fd);
+ return;
+ }
+ }
+
+ // handle case on iOS where sliceOffset in closure is wrong because file was thinned after cache was built
+ if ( (_dyldCacheAddress != nullptr) && !(((dyld_cache_header*)_dyldCacheAddress)->dylibsExpectedOnDisk) ) {
+ if ( sliceOffset != 0 ) {
+ if ( round_page_kernel(codeSignFileOffset+codeSignFileSize) == round_page_kernel(statBuf.st_size) ) {
+ // file is now thin
+ sliceOffset = 0;
+ }
+ }
+ }
+
+ // register code signature
+ uint64_t coveredCodeLength = UINT64_MAX;
+ if ( isCodeSigned ) {
+ auto sigTimer = ScopedTimer(DBG_DYLD_TIMING_ATTACH_CODESIGNATURE, 0, 0, 0);
+ fsignatures_t siginfo;
+ siginfo.fs_file_start = sliceOffset; // start of mach-o slice in fat file
+ siginfo.fs_blob_start = (void*)(long)(codeSignFileOffset); // start of CD in mach-o file
+ siginfo.fs_blob_size = codeSignFileSize; // size of CD
+ int result = fcntl(fd, F_ADDFILESIGS_RETURN, &siginfo);
+ if ( result == -1 ) {
+ int errnoCopy = errno;
+ if ( (errnoCopy == EPERM) || (errnoCopy == EBADEXEC) ) {
+ diag.error("code signature invalid (errno=%d) sliceOffset=0x%08llX, codeBlobOffset=0x%08X, codeBlobSize=0x%08X for '%s'",
+ errnoCopy, sliceOffset, codeSignFileOffset, codeSignFileSize, image->path());
+ }
+ else {
+ diag.error("fcntl(fd, F_ADDFILESIGS_RETURN) failed with errno=%d, sliceOffset=0x%08llX, codeBlobOffset=0x%08X, codeBlobSize=0x%08X for '%s'",
+ errnoCopy, sliceOffset, codeSignFileOffset, codeSignFileSize, image->path());
+ }
+ close(fd);
+ return;
+ }
+ coveredCodeLength = siginfo.fs_file_start;
+ if ( coveredCodeLength < codeSignFileOffset ) {
+ diag.error("code signature does not cover entire file up to signature");
+ close(fd);
+ return;
+ }
+ }
+
+ // <rdar://problem/41015217> dyld should use F_CHECK_LV even on unsigned binaries
+ {
+ // <rdar://problem/32684903> always call F_CHECK_LV to preflight
+ fchecklv checkInfo;
+ char messageBuffer[512];
+ messageBuffer[0] = '\0';
+ checkInfo.lv_file_start = sliceOffset;
+ checkInfo.lv_error_message_size = sizeof(messageBuffer);
+ checkInfo.lv_error_message = messageBuffer;
+ int res = fcntl(fd, F_CHECK_LV, &checkInfo);
+ if ( res == -1 ) {
+ diag.error("code signature in (%s) not valid for use in process: %s", image->path(), messageBuffer);
+ close(fd);
+ return;
+ }
+ }
+
+ // reserve address range
+ vm_address_t loadAddress = 0;
+ kern_return_t r = vm_allocate(mach_task_self(), &loadAddress, (vm_size_t)totalVMSize, VM_FLAGS_ANYWHERE);
+ if ( r != KERN_SUCCESS ) {
+ diag.error("vm_allocate(size=0x%0llX) failed with result=%d", totalVMSize, r);
+ close(fd);
+ return;
+ }
+
+ if ( sliceOffset != 0 )
+ _logSegments("dyld: Mapping %s (slice offset=%llu)\n", image->path(), sliceOffset);
+ else
+ _logSegments("dyld: Mapping %s\n", image->path());
+
+ // map each segment
+ __block bool mmapFailure = false;
+ __block const uint8_t* codeSignatureStartAddress = nullptr;
+ __block const uint8_t* linkeditEndAddress = nullptr;
+ __block bool mappedFirstSegment = false;
+ image->forEachDiskSegment(^(uint32_t segIndex, uint32_t fileOffset, uint32_t fileSize, int64_t vmOffset, uint64_t vmSize, uint8_t permissions, bool& stop) {
+ // <rdar://problem/32363581> Mapping zero filled segments fails with mmap of size 0
+ if ( fileSize == 0 )
+ return;
+ void* segAddress = mmap((void*)(loadAddress+vmOffset), fileSize, permissions, MAP_FIXED | MAP_PRIVATE, fd, sliceOffset+fileOffset);
+ int mmapErr = errno;
+ if ( segAddress == MAP_FAILED ) {
+ if ( mmapErr == EPERM ) {
+ if ( sandboxBlockedMmap(image->path()) )
+ diag.error("file system sandbox blocked mmap() of '%s'", image->path());
+ else
+ diag.error("code signing blocked mmap() of '%s'", image->path());
+ }
+ else {
+ diag.error("mmap(addr=0x%0llX, size=0x%08X) failed with errno=%d for %s", loadAddress+vmOffset, fileSize, mmapErr, image->path());
+ }
+ mmapFailure = true;
+ stop = true;
+ }
+ else if ( codeSignFileOffset > fileOffset ) {
+ codeSignatureStartAddress = (uint8_t*)segAddress + (codeSignFileOffset-fileOffset);
+ linkeditEndAddress = (uint8_t*)segAddress + vmSize;
+ }
+ // sanity check first segment is mach-o header
+ if ( (segAddress != MAP_FAILED) && !mappedFirstSegment ) {
+ mappedFirstSegment = true;
+ const MachOFile* mf = (MachOFile*)segAddress;
+ if ( !mf->isMachO(diag, fileSize) ) {
+ mmapFailure = true;
+ stop = true;
+ }
+ }
+ if ( !mmapFailure ) {
+ const MachOLoaded* lmo = (MachOLoaded*)loadAddress;
+ _logSegments("%14s (%c%c%c) 0x%012lX->0x%012lX \n", lmo->segmentName(segIndex),
+ (permissions & PROT_READ) ? 'r' : '.', (permissions & PROT_WRITE) ? 'w' : '.', (permissions & PROT_EXEC) ? 'x' : '.' ,
+ (long)segAddress, (long)segAddress+(long)vmSize-1);
+ }
+ });
+ if ( mmapFailure ) {
+ ::vm_deallocate(mach_task_self(), loadAddress, (vm_size_t)totalVMSize);
+ ::close(fd);
+ return;
+ }
+
+ // close file
+ close(fd);
+
+#if BUILDING_LIBDYLD
+ // verify file has not changed since closure was built by checking code signature has not changed
+ uint8_t cdHashExpected[20];
+ if ( image->hasCdHash(cdHashExpected) ) {
+ if ( codeSignatureStartAddress == nullptr ) {
+ diag.error("code signature missing");
+ }
+ else if ( codeSignatureStartAddress+codeSignFileSize > linkeditEndAddress ) {
+ diag.error("code signature extends beyond end of __LINKEDIT");
+ }
+ else {
+ uint8_t cdHashFound[20];
+ const MachOLoaded* lmo = (MachOLoaded*)loadAddress;
+ if ( lmo->cdHashOfCodeSignature(codeSignatureStartAddress, codeSignFileSize, cdHashFound) ) {
+ if ( ::memcmp(cdHashFound, cdHashExpected, 20) != 0 )
+ diag.error("code signature changed since closure was built");
+ }
+ else {
+ diag.error("code signature format invalid");
+ }
+ }
+ if ( diag.hasError() ) {
+ ::vm_deallocate(mach_task_self(), loadAddress, (vm_size_t)totalVMSize);
+ return;
+ }
+ }
+#endif
+
+#if __IPHONE_OS_VERSION_MIN_REQUIRED && !TARGET_IPHONE_SIMULATOR
+ // tell kernel about fairplay encrypted regions
+ uint32_t fpTextOffset;
+ uint32_t fpSize;
+ if ( image->isFairPlayEncrypted(fpTextOffset, fpSize) ) {
+ const mach_header* mh = (mach_header*)loadAddress;
+ int result = ::mremap_encrypted(((uint8_t*)mh) + fpTextOffset, fpSize, 1, mh->cputype, mh->cpusubtype);
+ if ( result != 0 ) {
+ diag.error("could not register fairplay decryption, mremap_encrypted() => %d", result);
+ ::vm_deallocate(mach_task_self(), loadAddress, (vm_size_t)totalVMSize);
+ return;
+ }
+ }
+#endif
+
+ _logLoads("dyld: load %s\n", image->path());
+
+ timer.setData4((uint64_t)loadAddress);
+ info.setLoadedAddress((MachOLoaded*)loadAddress);
+ info.setState(LoadedImage::State::mapped);
+}
+
+void Loader::unmapImage(LoadedImage& info)
+{
+ assert(info.loadedAddress() != nullptr);
+ ::vm_deallocate(mach_task_self(), (vm_address_t)info.loadedAddress(), (vm_size_t)(info.image()->vmSizeToMap()));
+ info.setLoadedAddress(nullptr);
+}
+
+void Loader::registerDOFs(const Array<DOFInfo>& dofs)
+{
+ if ( dofs.empty() )
+ return;
+
+ int fd = open("/dev/" DTRACEMNR_HELPER, O_RDWR);
+ if ( fd < 0 ) {
+ _logDofs("can't open /dev/" DTRACEMNR_HELPER " to register dtrace DOF sections\n");
+ }
+ else {
+ // allocate a buffer on the stack for the variable length dof_ioctl_data_t type
+ uint8_t buffer[sizeof(dof_ioctl_data_t) + dofs.count()*sizeof(dof_helper_t)];
+ dof_ioctl_data_t* ioctlData = (dof_ioctl_data_t*)buffer;
+
+ // fill in buffer with one dof_helper_t per DOF section
+ ioctlData->dofiod_count = dofs.count();
+ for (unsigned int i=0; i < dofs.count(); ++i) {
+ strlcpy(ioctlData->dofiod_helpers[i].dofhp_mod, dofs[i].imageShortName, DTRACE_MODNAMELEN);
+ ioctlData->dofiod_helpers[i].dofhp_dof = (uintptr_t)(dofs[i].dof);
+ ioctlData->dofiod_helpers[i].dofhp_addr = (uintptr_t)(dofs[i].dof);
+ }
+
+ // tell kernel about all DOF sections en mas
+ // pass pointer to ioctlData because ioctl() only copies a fixed size amount of data into kernel
+ user_addr_t val = (user_addr_t)(unsigned long)ioctlData;
+ if ( ioctl(fd, DTRACEHIOC_ADDDOF, &val) != -1 ) {
+ // kernel returns a unique identifier for each section in the dofiod_helpers[].dofhp_dof field.
+ // Note, the closure marked the image as being never unload, so we don't need to keep the ID around
+ // or support unregistering it later.
+ for (unsigned int i=0; i < dofs.count(); ++i) {
+ _logDofs("dyld: registering DOF section %p in %s with dtrace, ID=0x%08X\n",
+ dofs[i].dof, dofs[i].imageShortName, (int)(ioctlData->dofiod_helpers[i].dofhp_dof));
+ }
+ }
+ else {
+ _logDofs("dyld: ioctl to register dtrace DOF section failed\n");
+ }
+ close(fd);
+ }
+}
+
+bool Loader::dtraceUserProbesEnabled()
+{
+#if __IPHONE_OS_VERSION_MIN_REQUIRED && !TARGET_IPHONE_SIMULATOR
+ int dof_mode;
+ size_t dof_mode_size = sizeof(dof_mode);
+ if ( sysctlbyname("kern.dtrace.dof_mode", &dof_mode, &dof_mode_size, nullptr, 0) == 0 ) {
+ return ( dof_mode != 0 );
+ }
+ return false;
+#else
+ // dtrace is always available for macOS and simulators
+ return true;
+#endif
+}
+
+
+void Loader::vmAccountingSetSuspended(bool suspend, LogFunc logger)
+{
+#if __arm__ || __arm64__
+ // <rdar://problem/29099600> dyld should tell the kernel when it is doing fix-ups caused by roots
+ logger("vm.footprint_suspend=%d\n", suspend);
+ int newValue = suspend ? 1 : 0;
+ int oldValue = 0;
+ size_t newlen = sizeof(newValue);
+ size_t oldlen = sizeof(oldValue);
+ sysctlbyname("vm.footprint_suspend", &oldValue, &oldlen, &newValue, newlen);
+#endif
+}
+
+void Loader::applyFixupsToImage(Diagnostics& diag, LoadedImage& info)
+{
+ dyld3::ScopedTimer timer(DBG_DYLD_TIMING_APPLY_FIXUPS, (uint64_t)info.loadedAddress(), 0, 0);
+ closure::ImageNum cacheImageNum;
+ const char* leafName = info.image()->leafName();
+ const closure::Image* image = info.image();
+ const uint8_t* imageLoadAddress = (uint8_t*)info.loadedAddress();
+ uintptr_t slide = info.loadedAddress()->getSlide();
+ bool overrideOfCache = info.image()->isOverrideOfDyldCacheImage(cacheImageNum);
+ if ( overrideOfCache )
+ vmAccountingSetSuspended(true, _logFixups);
+ image->forEachFixup(^(uint64_t imageOffsetToRebase, bool &stop) {
+ uintptr_t* fixUpLoc = (uintptr_t*)(imageLoadAddress + imageOffsetToRebase);
+ *fixUpLoc += slide;
+ _logFixups("dyld: fixup: %s:%p += %p\n", leafName, fixUpLoc, (void*)slide);
+ },
+ ^(uint64_t imageOffsetToBind, closure::Image::ResolvedSymbolTarget bindTarget, bool &stop) {
+ uintptr_t* fixUpLoc = (uintptr_t*)(imageLoadAddress + imageOffsetToBind);
+ uintptr_t value = resolveTarget(bindTarget);
+ _logFixups("dyld: fixup: %s:%p = %p\n", leafName, fixUpLoc, (void*)value);
+ *fixUpLoc = value;
+ },
+ ^(uint64_t imageOffsetStart, const Array<closure::Image::ResolvedSymbolTarget>& targets, bool& stop) {
+ // walk each fixup in the chain
+ image->forEachChainedFixup((void*)imageLoadAddress, imageOffsetStart, ^(uint64_t* fixupLoc, MachOLoaded::ChainedFixupPointerOnDisk fixupInfo, bool& stopChain) {
+ if ( fixupInfo.authRebase.auth ) {
+ #if __has_feature(ptrauth_calls)
+ if ( fixupInfo.authBind.bind ) {
+ closure::Image::ResolvedSymbolTarget bindTarget = targets[fixupInfo.authBind.ordinal];
+ uint64_t targetAddr = resolveTarget(bindTarget);
+ // Don't sign missing weak imports.
+ if (targetAddr != 0)
+ targetAddr = fixupInfo.signPointer(fixupLoc, targetAddr);
+ _logFixups("dyld: fixup: *%p = %p (JOP: diversity 0x%04X, addr-div=%d, key=%s)\n",
+ fixupLoc, (void*)targetAddr, fixupInfo.authBind.diversity, fixupInfo.authBind.addrDiv, fixupInfo.authBind.keyName());
+ *fixupLoc = targetAddr;
+ }
+ else {
+ uint64_t targetAddr = (uint64_t)imageLoadAddress + fixupInfo.authRebase.target;
+ targetAddr = fixupInfo.signPointer(fixupLoc, targetAddr);
+ _logFixups("dyld: fixup: *%p = %p (JOP: diversity 0x%04X, addr-div=%d, key=%s)\n",
+ fixupLoc, (void*)targetAddr, fixupInfo.authRebase.diversity, fixupInfo.authRebase.addrDiv, fixupInfo.authRebase.keyName());
+ *fixupLoc = targetAddr;
+ }
+ #else
+ diag.error("malformed chained pointer");
+ stop = true;
+ stopChain = true;
+ #endif
+ }
+ else {
+ if ( fixupInfo.plainRebase.bind ) {
+ closure::Image::ResolvedSymbolTarget bindTarget = targets[fixupInfo.plainBind.ordinal];
+ uint64_t targetAddr = resolveTarget(bindTarget) + fixupInfo.plainBind.signExtendedAddend();
+ _logFixups("dyld: fixup: %s:%p = %p\n", leafName, fixupLoc, (void*)targetAddr);
+ *fixupLoc = targetAddr;
+ }
+ else {
+ uint64_t targetAddr = fixupInfo.plainRebase.signExtendedTarget() + slide;
+ _logFixups("dyld: fixup: %s:%p += %p\n", leafName, fixupLoc, (void*)slide);
+ *fixupLoc = targetAddr;
+ }
+ }
+ });
+ });
+
+#if __i386__
+ __block bool segmentsMadeWritable = false;
+ image->forEachTextReloc(^(uint32_t imageOffsetToRebase, bool& stop) {
+ if ( !segmentsMadeWritable )
+ setSegmentProtects(info, true);
+ uintptr_t* fixUpLoc = (uintptr_t*)(imageLoadAddress + imageOffsetToRebase);
+ *fixUpLoc += slide;
+ _logFixups("dyld: fixup: %s:%p += %p\n", leafName, fixUpLoc, (void*)slide);
+ },
+ ^(uint32_t imageOffsetToBind, closure::Image::ResolvedSymbolTarget bindTarget, bool& stop) {
+ // FIXME
+ });
+ if ( segmentsMadeWritable )
+ setSegmentProtects(info, false);
+#endif
+
+ if ( overrideOfCache )
+ vmAccountingSetSuspended(false, _logFixups);
+}
+
+#if __i386__
+void Loader::setSegmentProtects(const LoadedImage& info, bool write)
+{
+ info.image()->forEachDiskSegment(^(uint32_t segIndex, uint32_t fileOffset, uint32_t fileSize, int64_t vmOffset, uint64_t vmSize, uint8_t protections, bool& segStop) {
+ if ( protections & VM_PROT_WRITE )
+ return;
+ uint32_t regionProt = protections;
+ if ( write )
+ regionProt = VM_PROT_WRITE | VM_PROT_READ;
+ kern_return_t r = vm_protect(mach_task_self(), ((uintptr_t)info.loadedAddress())+(uintptr_t)vmOffset, (uintptr_t)vmSize, false, regionProt);
+ assert( r == KERN_SUCCESS );
+ });
+}
+#endif
+
+#if BUILDING_DYLD
+void forEachLineInFile(const char* buffer, size_t bufferLen, void (^lineHandler)(const char* line, bool& stop))
+{
+ bool stop = false;
+ const char* const eof = &buffer[bufferLen];
+ for (const char* s = buffer; s < eof; ++s) {
+ char lineBuffer[MAXPATHLEN];
+ char* t = lineBuffer;
+ char* tEnd = &lineBuffer[MAXPATHLEN];
+ while ( (s < eof) && (t != tEnd) ) {
+ if ( *s == '\n' )
+ break;
+ *t++ = *s++;
+ }
+ *t = '\0';
+ lineHandler(lineBuffer, stop);
+ if ( stop )
+ break;
+ }
+}
+
+void forEachLineInFile(const char* path, void (^lineHandler)(const char* line, bool& stop))
+{
+ int fd = dyld::my_open(path, O_RDONLY, 0);
+ if ( fd != -1 ) {
+ struct stat statBuf;
+ if ( fstat(fd, &statBuf) == 0 ) {
+ const char* lines = (const char*)mmap(nullptr, (size_t)statBuf.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+ if ( lines != MAP_FAILED ) {
+ forEachLineInFile(lines, (size_t)statBuf.st_size, lineHandler);
+ munmap((void*)lines, (size_t)statBuf.st_size);
+ }
+ }
+ close(fd);
+ }
+}
+
+
+bool internalInstall()
+{
+#if TARGET_IPHONE_SIMULATOR
+ return false;
+#elif __IPHONE_OS_VERSION_MIN_REQUIRED
+ uint32_t devFlags = *((uint32_t*)_COMM_PAGE_DEV_FIRM);
+ return ( (devFlags & 1) == 1 );
+#else
+ return ( csr_check(CSR_ALLOW_APPLE_INTERNAL) == 0 );
+#endif
+}
+
+/* Checks to see if there are any args that impact dyld. These args
+ * can be set sevaral ways. These will only be honored on development
+ * and Apple Internal builds.
+ *
+ * First the existence of a file is checked for:
+ * /S/L/C/com.apple.dyld/dyld-bootargs
+ * If it exists it will be mapped and scanned line by line. If the executable
+ * exists in the file then the arguments on its line will be applied. "*" may
+ * be used a wildcard to represent all apps. First matching line will be used,
+ * the wild card must be one the last line. Additionally, lines must end with
+ * a "\n"
+ *
+ *
+ * SAMPLE FILE:
+
+ /bin/ls:force_dyld2=1
+ /usr/bin/sw_vers:force_dyld2=1
+*:force_dyld3=1
+EOL
+
+ If no file exists then the kernel boot-args will be scanned.
+ */
+bool bootArgsContains(const char* arg)
+{
+ //FIXME: Use strnstr(). Unfortunately we are missing an imp libc.
+#if TARGET_IPHONE_SIMULATOR
+ return false;
+#else
+ // don't check for boot-args on customer installs
+ if ( !internalInstall() )
+ return false;
+
+ char pathBuffer[MAXPATHLEN+1];
+#if __IPHONE_OS_VERSION_MIN_REQUIRED
+ strlcpy(pathBuffer, IPHONE_DYLD_SHARED_CACHE_DIR, sizeof(IPHONE_DYLD_SHARED_CACHE_DIR));
+#else
+ strlcpy(pathBuffer, MACOSX_DYLD_SHARED_CACHE_DIR, sizeof(MACOSX_DYLD_SHARED_CACHE_DIR));
+#endif
+ strlcat(pathBuffer, "dyld-bootargs", MAXPATHLEN+1);
+ __block bool result = false;
+ forEachLineInFile(pathBuffer, ^(const char* line, bool& stop) {
+ const char* delim = strchr(line, ':');
+ if ( delim == nullptr )
+ return;
+ char binary[MAXPATHLEN];
+ char options[MAXPATHLEN];
+ strlcpy(binary, line, MAXPATHLEN);
+ binary[delim-line] = '\0';
+ strlcpy(options, delim+1, MAXPATHLEN);
+ if ( (strcmp(dyld::getExecutablePath(), binary) == 0) || (strcmp("*", binary) == 0) ) {
+ result = (strstr(options, arg) != nullptr);
+ return;
+ }
+ });
+
+ // get length of full boot-args string
+ size_t len;
+ if ( sysctlbyname("kern.bootargs", NULL, &len, NULL, 0) != 0 )
+ return false;
+
+ // get copy of boot-args string
+ char bootArgsBuffer[len];
+ if ( sysctlbyname("kern.bootargs", bootArgsBuffer, &len, NULL, 0) != 0 )
+ return false;
+
+ // return true if 'arg' is a sub-string of boot-args
+ return (strstr(bootArgsBuffer, arg) != nullptr);
+#endif
+}
+#endif
+
+#if BUILDING_LIBDYLD
+// hack because libdyld.dylib should not link with libc++.dylib
+extern "C" void __cxa_pure_virtual() __attribute__((visibility("hidden")));
+void __cxa_pure_virtual()
+{
+ abort();
+}
+#endif
+
+} // namespace dyld3
+
+
+
+
+