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+++ dyld/dyld-635.2/src/ImageLoaderMachO.cpp
@@ -0,0 +1,2856 @@
+/* -*- mode: C++; c-basic-offset: 4; tab-width: 4 -*-
+ *
+ * Copyright (c) 2004-2010 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@
+ */
+
+// work around until conformance work is complete rdar://problem/4508801
+#define __srr0 srr0
+#define __eip eip
+#define __rip rip
+
+#define __STDC_LIMIT_MACROS
+#include <string.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/fcntl.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <mach/mach.h>
+#include <mach/thread_status.h>
+#include <mach-o/loader.h>
+#include <mach-o/nlist.h>
+#include <sys/sysctl.h>
+#include <sys/syscall.h>
+#include <libkern/OSAtomic.h>
+#include <libkern/OSCacheControl.h>
+#include <stdint.h>
+#include <System/sys/codesign.h>
+
+#if __has_feature(ptrauth_calls)
+#include <ptrauth.h>
+#endif
+
+#include "ImageLoaderMachO.h"
+#include "ImageLoaderMachOCompressed.h"
+#if SUPPORT_CLASSIC_MACHO
+#include "ImageLoaderMachOClassic.h"
+#endif
+#include "mach-o/dyld_images.h"
+#include "Tracing.h"
+#include "dyld.h"
+
+// <rdar://problem/8718137> use stack guard random value to add padding between dylibs
+extern "C" long __stack_chk_guard;
+
+#ifndef LC_LOAD_UPWARD_DYLIB
+ #define LC_LOAD_UPWARD_DYLIB (0x23|LC_REQ_DYLD) /* load of dylib whose initializers run later */
+#endif
+
+#ifndef LC_VERSION_MIN_TVOS
+ #define LC_VERSION_MIN_TVOS 0x2F
+#endif
+
+#ifndef LC_VERSION_MIN_WATCHOS
+ #define LC_VERSION_MIN_WATCHOS 0x30
+#endif
+
+#ifndef LC_BUILD_VERSION
+ #define LC_BUILD_VERSION 0x32 /* build for platform min OS version */
+
+ /*
+ * The build_version_command contains the min OS version on which this
+ * binary was built to run for its platform. The list of known platforms and
+ * tool values following it.
+ */
+ struct build_version_command {
+ uint32_t cmd; /* LC_BUILD_VERSION */
+ uint32_t cmdsize; /* sizeof(struct build_version_command) plus */
+ /* ntools * sizeof(struct build_tool_version) */
+ uint32_t platform; /* platform */
+ uint32_t minos; /* X.Y.Z is encoded in nibbles xxxx.yy.zz */
+ uint32_t sdk; /* X.Y.Z is encoded in nibbles xxxx.yy.zz */
+ uint32_t ntools; /* number of tool entries following this */
+ };
+
+ struct build_tool_version {
+ uint32_t tool; /* enum for the tool */
+ uint32_t version; /* version number of the tool */
+ };
+
+ /* Known values for the platform field above. */
+ #define PLATFORM_MACOS 1
+ #define PLATFORM_IOS 2
+ #define PLATFORM_TVOS 3
+ #define PLATFORM_WATCHOS 4
+ #define PLATFORM_BRIDGEOS 5
+
+ /* Known values for the tool field above. */
+ #define TOOL_CLANG 1
+ #define TOOL_SWIFT 2
+ #define TOOL_LD 3
+#endif
+
+#define LIBSYSTEM_DYLIB_PATH "/usr/lib/libSystem.B.dylib"
+
+// relocation_info.r_length field has value 3 for 64-bit executables and value 2 for 32-bit executables
+#if __LP64__
+ #define LC_SEGMENT_COMMAND LC_SEGMENT_64
+ #define LC_ROUTINES_COMMAND LC_ROUTINES_64
+ #define LC_SEGMENT_COMMAND_WRONG LC_SEGMENT
+ struct macho_segment_command : public segment_command_64 {};
+ struct macho_section : public section_64 {};
+ struct macho_routines_command : public routines_command_64 {};
+#else
+ #define LC_SEGMENT_COMMAND LC_SEGMENT
+ #define LC_ROUTINES_COMMAND LC_ROUTINES
+ #define LC_SEGMENT_COMMAND_WRONG LC_SEGMENT_64
+ struct macho_segment_command : public segment_command {};
+ struct macho_section : public section {};
+ struct macho_routines_command : public routines_command {};
+#endif
+
+uint32_t ImageLoaderMachO::fgSymbolTableBinarySearchs = 0;
+
+
+ImageLoaderMachO::ImageLoaderMachO(const macho_header* mh, const char* path, unsigned int segCount,
+ uint32_t segOffsets[], unsigned int libCount)
+ : ImageLoader(path, libCount), fCoveredCodeLength(0), fMachOData((uint8_t*)mh), fLinkEditBase(NULL), fSlide(0),
+ fEHFrameSectionOffset(0), fUnwindInfoSectionOffset(0), fDylibIDOffset(0),
+fSegmentsCount(segCount), fIsSplitSeg(false), fInSharedCache(false),
+#if TEXT_RELOC_SUPPORT
+ fTextSegmentRebases(false),
+ fTextSegmentBinds(false),
+#endif
+#if __i386__
+ fReadOnlyImportSegment(false),
+#endif
+ fHasSubLibraries(false), fHasSubUmbrella(false), fInUmbrella(false), fHasDOFSections(false), fHasDashInit(false),
+ fHasInitializers(false), fHasTerminators(false), fNotifyObjC(false), fRetainForObjC(false), fRegisteredAsRequiresCoalescing(false), fOverrideOfCacheImageNum(0)
+{
+ fIsSplitSeg = ((mh->flags & MH_SPLIT_SEGS) != 0);
+
+ // construct SegmentMachO object for each LC_SEGMENT cmd using "placement new" to put
+ // each SegmentMachO object in array at end of ImageLoaderMachO object
+ const uint32_t cmd_count = mh->ncmds;
+ const struct load_command* const cmds = (struct load_command*)&fMachOData[sizeof(macho_header)];
+ const struct load_command* cmd = cmds;
+ for (uint32_t i = 0, segIndex=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 ) {
+ // record offset of load command
+ segOffsets[segIndex++] = (uint32_t)((uint8_t*)segCmd - fMachOData);
+ }
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+
+}
+
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
+static uintptr_t pageAlign(uintptr_t value)
+{
+ return (value + 4095) & (-4096);
+}
+#endif
+
+// determine if this mach-o file has classic or compressed LINKEDIT and number of segments it has
+void ImageLoaderMachO::sniffLoadCommands(const macho_header* mh, const char* path, bool inCache, bool* compressed,
+ unsigned int* segCount, unsigned int* libCount, const LinkContext& context,
+ const linkedit_data_command** codeSigCmd,
+ const encryption_info_command** encryptCmd)
+{
+ *compressed = false;
+ *segCount = 0;
+ *libCount = 0;
+ *codeSigCmd = NULL;
+ *encryptCmd = NULL;
+
+ const uint32_t cmd_count = mh->ncmds;
+ const uint32_t sizeofcmds = mh->sizeofcmds;
+ if ( sizeofcmds > (MAX_MACH_O_HEADER_AND_LOAD_COMMANDS_SIZE-sizeof(macho_header)) )
+ dyld::throwf("malformed mach-o: load commands size (%u) > %u", sizeofcmds, MAX_MACH_O_HEADER_AND_LOAD_COMMANDS_SIZE);
+ if ( cmd_count > (sizeofcmds/sizeof(load_command)) )
+ dyld::throwf("malformed mach-o: ncmds (%u) too large to fit in sizeofcmds (%u)", cmd_count, sizeofcmds);
+ const struct load_command* const startCmds = (struct load_command*)(((uint8_t*)mh) + sizeof(macho_header));
+ const struct load_command* const endCmds = (struct load_command*)(((uint8_t*)mh) + sizeof(macho_header) + sizeofcmds);
+ const struct load_command* cmd = startCmds;
+ bool foundLoadCommandSegment = false;
+ const macho_segment_command* linkeditSegCmd = NULL;
+ const macho_segment_command* startOfFileSegCmd = NULL;
+ const dyld_info_command* dyldInfoCmd = NULL;
+ const symtab_command* symTabCmd = NULL;
+ const dysymtab_command* dynSymbTabCmd = NULL;
+ for (uint32_t i = 0; i < cmd_count; ++i) {
+ uint32_t cmdLength = cmd->cmdsize;
+ const macho_segment_command* segCmd;
+ const dylib_command* dylibCmd;
+ if ( cmdLength < 8 ) {
+ dyld::throwf("malformed mach-o image: load command #%d length (%u) too small in %s",
+ i, cmdLength, path);
+ }
+ const struct load_command* const nextCmd = (const struct load_command*)(((char*)cmd)+cmdLength);
+ if ( (nextCmd > endCmds) || (nextCmd < cmd) ) {
+ dyld::throwf("malformed mach-o image: load command #%d length (%u) would exceed sizeofcmds (%u) in %s",
+ i, cmdLength, mh->sizeofcmds, path);
+ }
+ switch (cmd->cmd) {
+ case LC_DYLD_INFO:
+ case LC_DYLD_INFO_ONLY:
+ if ( cmd->cmdsize != sizeof(dyld_info_command) )
+ throw "malformed mach-o image: LC_DYLD_INFO size wrong";
+ dyldInfoCmd = (struct dyld_info_command*)cmd;
+ *compressed = true;
+ break;
+ case LC_SEGMENT_COMMAND:
+ segCmd = (struct macho_segment_command*)cmd;
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
+ // rdar://problem/19617624 allow unmapped segments on OSX (but not iOS)
+ if ( ((segCmd->filesize) > pageAlign(segCmd->vmsize)) && (segCmd->vmsize != 0) )
+#else
+ // <rdar://problem/19986776> dyld should support non-allocatable __LLVM segment
+ if ( (segCmd->filesize > segCmd->vmsize) && ((segCmd->vmsize != 0) || ((segCmd->flags & SG_NORELOC) == 0)) )
+#endif
+ dyld::throwf("malformed mach-o image: segment load command %s filesize (0x%0lX) is larger than vmsize (0x%0lX)", segCmd->segname, (long)segCmd->filesize , (long)segCmd->vmsize );
+ if ( cmd->cmdsize < sizeof(macho_segment_command) )
+ throw "malformed mach-o image: LC_SEGMENT size too small";
+ if ( cmd->cmdsize != (sizeof(macho_segment_command) + segCmd->nsects * sizeof(macho_section)) )
+ throw "malformed mach-o image: LC_SEGMENT size wrong for number of sections";
+ // ignore zero-sized segments
+ if ( segCmd->vmsize != 0 )
+ *segCount += 1;
+ if ( strcmp(segCmd->segname, "__LINKEDIT") == 0 ) {
+ #if TARGET_IPHONE_SIMULATOR
+ // Note: should check on all platforms that __LINKEDIT is read-only, but <rdar://problem/22637626&22525618>
+ if ( segCmd->initprot != VM_PROT_READ )
+ throw "malformed mach-o image: __LINKEDIT segment does not have read-only permissions";
+ #endif
+ if ( segCmd->fileoff == 0 )
+ throw "malformed mach-o image: __LINKEDIT has fileoff==0 which overlaps mach_header";
+ if ( linkeditSegCmd != NULL )
+ throw "malformed mach-o image: multiple __LINKEDIT segments";
+ linkeditSegCmd = segCmd;
+ }
+ else {
+ if ( segCmd->initprot & 0xFFFFFFF8 )
+ dyld::throwf("malformed mach-o image: %s segment has invalid permission bits (0x%X) in initprot", segCmd->segname, segCmd->initprot);
+ if ( segCmd->maxprot & 0xFFFFFFF8 )
+ dyld::throwf("malformed mach-o image: %s segment has invalid permission bits (0x%X) in maxprot", segCmd->segname, segCmd->maxprot);
+ if ( (segCmd->initprot != 0) && ((segCmd->initprot & VM_PROT_READ) == 0) )
+ dyld::throwf("malformed mach-o image: %s segment is not mapped readable", segCmd->segname);
+ }
+ if ( (segCmd->fileoff == 0) && (segCmd->filesize != 0) ) {
+ if ( (segCmd->initprot & VM_PROT_READ) == 0 )
+ dyld::throwf("malformed mach-o image: %s segment maps start of file but is not readable", segCmd->segname);
+ if ( (segCmd->initprot & VM_PROT_WRITE) == VM_PROT_WRITE ) {
+ if ( context.strictMachORequired )
+ dyld::throwf("malformed mach-o image: %s segment maps start of file but is writable", segCmd->segname);
+ }
+ if ( segCmd->filesize < (sizeof(macho_header) + mh->sizeofcmds) )
+ dyld::throwf("malformed mach-o image: %s segment does not map all of load commands", segCmd->segname);
+ if ( startOfFileSegCmd != NULL )
+ dyld::throwf("malformed mach-o image: multiple segments map start of file: %s %s", startOfFileSegCmd->segname, segCmd->segname);
+ startOfFileSegCmd = segCmd;
+ }
+ if ( context.strictMachORequired ) {
+ uintptr_t vmStart = segCmd->vmaddr;
+ uintptr_t vmSize = segCmd->vmsize;
+ uintptr_t vmEnd = vmStart + vmSize;
+ uintptr_t fileStart = segCmd->fileoff;
+ uintptr_t fileSize = segCmd->filesize;
+ if ( (intptr_t)(vmSize) < 0 )
+ dyld::throwf("malformed mach-o image: segment load command %s vmsize too large in %s", segCmd->segname, path);
+ if ( vmStart > vmEnd )
+ dyld::throwf("malformed mach-o image: segment load command %s wraps around address space", segCmd->segname);
+ if ( vmSize != fileSize ) {
+ if ( segCmd->initprot == 0 ) {
+ // allow: fileSize == 0 && initprot == 0 e.g. __PAGEZERO
+ // allow: vmSize == 0 && initprot == 0 e.g. __LLVM
+ if ( (fileSize != 0) && (vmSize != 0) )
+ dyld::throwf("malformed mach-o image: unaccessable segment %s has non-zero filesize and vmsize", segCmd->segname);
+ }
+ else {
+ // allow: vmSize > fileSize && initprot != X e.g. __DATA
+ if ( vmSize < fileSize ) {
+ dyld::throwf("malformed mach-o image: segment %s has vmsize < filesize", segCmd->segname);
+ }
+ if ( segCmd->initprot & VM_PROT_EXECUTE ) {
+ dyld::throwf("malformed mach-o image: segment %s has vmsize != filesize and is executable", segCmd->segname);
+ }
+ }
+ }
+ if ( inCache ) {
+ if ( (fileSize != 0) && (segCmd->initprot == (VM_PROT_READ | VM_PROT_EXECUTE)) ) {
+ if ( foundLoadCommandSegment )
+ throw "load commands in multiple segments";
+ foundLoadCommandSegment = true;
+ }
+ }
+ else if ( (fileStart < mh->sizeofcmds) && (fileSize != 0) ) {
+ // <rdar://problem/7942521> all load commands must be in an executable segment
+ if ( (fileStart != 0) || (fileSize < (mh->sizeofcmds+sizeof(macho_header))) )
+ dyld::throwf("malformed mach-o image: segment %s does not span all load commands", segCmd->segname);
+ if ( segCmd->initprot != (VM_PROT_READ | VM_PROT_EXECUTE) )
+ dyld::throwf("malformed mach-o image: load commands found in segment %s with wrong permissions", segCmd->segname);
+ if ( foundLoadCommandSegment )
+ throw "load commands in multiple segments";
+ foundLoadCommandSegment = true;
+ }
+
+ const struct macho_section* const sectionsStart = (struct macho_section*)((char*)segCmd + sizeof(struct macho_segment_command));
+ const struct macho_section* const sectionsEnd = §ionsStart[segCmd->nsects];
+ for (const struct macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
+ if (!inCache && sect->offset != 0 && ((sect->offset + sect->size) > (segCmd->fileoff + segCmd->filesize)))
+ dyld::throwf("malformed mach-o image: section %s,%s of '%s' exceeds segment %s booundary", sect->segname, sect->sectname, path, segCmd->segname);
+ }
+ }
+ break;
+ case LC_SEGMENT_COMMAND_WRONG:
+ dyld::throwf("malformed mach-o image: wrong LC_SEGMENT[_64] for architecture");
+ break;
+ case LC_LOAD_DYLIB:
+ case LC_LOAD_WEAK_DYLIB:
+ case LC_REEXPORT_DYLIB:
+ case LC_LOAD_UPWARD_DYLIB:
+ *libCount += 1;
+ // fall thru
+ case LC_ID_DYLIB:
+ dylibCmd = (dylib_command*)cmd;
+ if ( dylibCmd->dylib.name.offset > cmdLength )
+ dyld::throwf("malformed mach-o image: dylib load command #%d has offset (%u) outside its size (%u)", i, dylibCmd->dylib.name.offset, cmdLength);
+ if ( (dylibCmd->dylib.name.offset + strlen((char*)dylibCmd + dylibCmd->dylib.name.offset) + 1) > cmdLength )
+ dyld::throwf("malformed mach-o image: dylib load command #%d string extends beyond end of load command", i);
+ break;
+ case LC_CODE_SIGNATURE:
+ if ( cmd->cmdsize != sizeof(linkedit_data_command) )
+ throw "malformed mach-o image: LC_CODE_SIGNATURE size wrong";
+ // <rdar://problem/22799652> only support one LC_CODE_SIGNATURE per image
+ if ( *codeSigCmd != NULL )
+ throw "malformed mach-o image: multiple LC_CODE_SIGNATURE load commands";
+ *codeSigCmd = (struct linkedit_data_command*)cmd;
+ break;
+ case LC_ENCRYPTION_INFO:
+ if ( cmd->cmdsize != sizeof(encryption_info_command) )
+ throw "malformed mach-o image: LC_ENCRYPTION_INFO size wrong";
+ // <rdar://problem/22799652> only support one LC_ENCRYPTION_INFO per image
+ if ( *encryptCmd != NULL )
+ throw "malformed mach-o image: multiple LC_ENCRYPTION_INFO load commands";
+ *encryptCmd = (encryption_info_command*)cmd;
+ break;
+ case LC_ENCRYPTION_INFO_64:
+ if ( cmd->cmdsize != sizeof(encryption_info_command_64) )
+ throw "malformed mach-o image: LC_ENCRYPTION_INFO_64 size wrong";
+ // <rdar://problem/22799652> only support one LC_ENCRYPTION_INFO_64 per image
+ if ( *encryptCmd != NULL )
+ throw "malformed mach-o image: multiple LC_ENCRYPTION_INFO_64 load commands";
+ *encryptCmd = (encryption_info_command*)cmd;
+ break;
+ case LC_SYMTAB:
+ if ( cmd->cmdsize != sizeof(symtab_command) )
+ throw "malformed mach-o image: LC_SYMTAB size wrong";
+ symTabCmd = (symtab_command*)cmd;
+ break;
+ case LC_DYSYMTAB:
+ if ( cmd->cmdsize != sizeof(dysymtab_command) )
+ throw "malformed mach-o image: LC_DYSYMTAB size wrong";
+ dynSymbTabCmd = (dysymtab_command*)cmd;
+ break;
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
+ // <rdar://problem/26797345> error when loading iOS Simulator mach-o binary into macOS process
+ case LC_VERSION_MIN_WATCHOS:
+ case LC_VERSION_MIN_TVOS:
+ case LC_VERSION_MIN_IPHONEOS:
+ if ( !context.marzipan )
+ throw "mach-o, but built for simulator (not macOS)";
+ break;
+#endif
+ }
+ cmd = nextCmd;
+ }
+
+ if ( context.strictMachORequired && !foundLoadCommandSegment )
+ throw "load commands not in a segment";
+ if ( linkeditSegCmd == NULL )
+ throw "malformed mach-o image: missing __LINKEDIT segment";
+ if ( !inCache && (startOfFileSegCmd == NULL) )
+ throw "malformed mach-o image: missing __TEXT segment that maps start of file";
+ // <rdar://problem/13145644> verify every segment does not overlap another segment
+ if ( context.strictMachORequired ) {
+ uintptr_t lastFileStart = 0;
+ uintptr_t linkeditFileStart = 0;
+ const struct load_command* cmd1 = startCmds;
+ for (uint32_t i = 0; i < cmd_count; ++i) {
+ if ( cmd1->cmd == LC_SEGMENT_COMMAND ) {
+ struct macho_segment_command* segCmd1 = (struct macho_segment_command*)cmd1;
+ uintptr_t vmStart1 = segCmd1->vmaddr;
+ uintptr_t vmEnd1 = segCmd1->vmaddr + segCmd1->vmsize;
+ uintptr_t fileStart1 = segCmd1->fileoff;
+ uintptr_t fileEnd1 = segCmd1->fileoff + segCmd1->filesize;
+
+ if (fileStart1 > lastFileStart)
+ lastFileStart = fileStart1;
+
+ if ( strcmp(&segCmd1->segname[0], "__LINKEDIT") == 0 ) {
+ linkeditFileStart = fileStart1;
+ }
+
+ const struct load_command* cmd2 = startCmds;
+ for (uint32_t j = 0; j < cmd_count; ++j) {
+ if ( cmd2 == cmd1 )
+ continue;
+ if ( cmd2->cmd == LC_SEGMENT_COMMAND ) {
+ struct macho_segment_command* segCmd2 = (struct macho_segment_command*)cmd2;
+ uintptr_t vmStart2 = segCmd2->vmaddr;
+ uintptr_t vmEnd2 = segCmd2->vmaddr + segCmd2->vmsize;
+ uintptr_t fileStart2 = segCmd2->fileoff;
+ uintptr_t fileEnd2 = segCmd2->fileoff + segCmd2->filesize;
+ if ( ((vmStart2 <= vmStart1) && (vmEnd2 > vmStart1) && (vmEnd1 > vmStart1))
+ || ((vmStart2 >= vmStart1) && (vmStart2 < vmEnd1) && (vmEnd2 > vmStart2)) )
+ dyld::throwf("malformed mach-o image: segment %s vm overlaps segment %s", segCmd1->segname, segCmd2->segname);
+ if ( ((fileStart2 <= fileStart1) && (fileEnd2 > fileStart1) && (fileEnd1 > fileStart1))
+ || ((fileStart2 >= fileStart1) && (fileStart2 < fileEnd1) && (fileEnd2 > fileStart2)) )
+ dyld::throwf("malformed mach-o image: segment %s file content overlaps segment %s", segCmd1->segname, segCmd2->segname);
+ }
+ cmd2 = (const struct load_command*)(((char*)cmd2)+cmd2->cmdsize);
+ }
+ }
+ cmd1 = (const struct load_command*)(((char*)cmd1)+cmd1->cmdsize);
+ }
+
+ if (lastFileStart != linkeditFileStart)
+ dyld::throwf("malformed mach-o image: __LINKEDIT must be last segment");
+ }
+
+ // validate linkedit content
+ if ( (dyldInfoCmd == NULL) && (symTabCmd == NULL) )
+ throw "malformed mach-o image: missing LC_SYMTAB or LC_DYLD_INFO";
+ if ( dynSymbTabCmd == NULL )
+ throw "malformed mach-o image: missing LC_DYSYMTAB";
+
+ uint32_t linkeditFileOffsetStart = (uint32_t)linkeditSegCmd->fileoff;
+ uint32_t linkeditFileOffsetEnd = (uint32_t)linkeditSegCmd->fileoff + (uint32_t)linkeditSegCmd->filesize;
+
+ if ( !inCache && (dyldInfoCmd != NULL) && context.strictMachORequired ) {
+ // validate all LC_DYLD_INFO chunks fit in LINKEDIT and don't overlap
+ uint32_t offset = linkeditFileOffsetStart;
+ if ( dyldInfoCmd->rebase_size != 0 ) {
+ if ( dyldInfoCmd->rebase_size & 0x80000000 )
+ throw "malformed mach-o image: dyld rebase info size overflow";
+ if ( dyldInfoCmd->rebase_off < offset )
+ throw "malformed mach-o image: dyld rebase info underruns __LINKEDIT";
+ offset = dyldInfoCmd->rebase_off + dyldInfoCmd->rebase_size;
+ if ( offset > linkeditFileOffsetEnd )
+ throw "malformed mach-o image: dyld rebase info overruns __LINKEDIT";
+ }
+ if ( dyldInfoCmd->bind_size != 0 ) {
+ if ( dyldInfoCmd->bind_size & 0x80000000 )
+ throw "malformed mach-o image: dyld bind info size overflow";
+ if ( dyldInfoCmd->bind_off < offset )
+ throw "malformed mach-o image: dyld bind info overlaps rebase info";
+ offset = dyldInfoCmd->bind_off + dyldInfoCmd->bind_size;
+ if ( offset > linkeditFileOffsetEnd )
+ throw "malformed mach-o image: dyld bind info overruns __LINKEDIT";
+ }
+ if ( dyldInfoCmd->weak_bind_size != 0 ) {
+ if ( dyldInfoCmd->weak_bind_size & 0x80000000 )
+ throw "malformed mach-o image: dyld weak bind info size overflow";
+ if ( dyldInfoCmd->weak_bind_off < offset )
+ throw "malformed mach-o image: dyld weak bind info overlaps bind info";
+ offset = dyldInfoCmd->weak_bind_off + dyldInfoCmd->weak_bind_size;
+ if ( offset > linkeditFileOffsetEnd )
+ throw "malformed mach-o image: dyld weak bind info overruns __LINKEDIT";
+ }
+ if ( dyldInfoCmd->lazy_bind_size != 0 ) {
+ if ( dyldInfoCmd->lazy_bind_size & 0x80000000 )
+ throw "malformed mach-o image: dyld lazy bind info size overflow";
+ if ( dyldInfoCmd->lazy_bind_off < offset )
+ throw "malformed mach-o image: dyld lazy bind info overlaps weak bind info";
+ offset = dyldInfoCmd->lazy_bind_off + dyldInfoCmd->lazy_bind_size;
+ if ( offset > linkeditFileOffsetEnd )
+ throw "malformed mach-o image: dyld lazy bind info overruns __LINKEDIT";
+ }
+ if ( dyldInfoCmd->export_size != 0 ) {
+ if ( dyldInfoCmd->export_size & 0x80000000 )
+ throw "malformed mach-o image: dyld export info size overflow";
+ if ( dyldInfoCmd->export_off < offset )
+ throw "malformed mach-o image: dyld export info overlaps lazy bind info";
+ offset = dyldInfoCmd->export_off + dyldInfoCmd->export_size;
+ if ( offset > linkeditFileOffsetEnd )
+ throw "malformed mach-o image: dyld export info overruns __LINKEDIT";
+ }
+ }
+
+ if ( symTabCmd != NULL ) {
+ // validate symbol table fits in LINKEDIT
+ if ( (symTabCmd->nsyms > 0) && (symTabCmd->symoff < linkeditFileOffsetStart) )
+ throw "malformed mach-o image: symbol table underruns __LINKEDIT";
+ if ( symTabCmd->nsyms > 0x10000000 )
+ throw "malformed mach-o image: symbol table too large";
+ uint32_t symbolsSize = symTabCmd->nsyms * sizeof(macho_nlist);
+ if ( symbolsSize > linkeditSegCmd->filesize )
+ throw "malformed mach-o image: symbol table overruns __LINKEDIT";
+ if ( symTabCmd->symoff + symbolsSize < symTabCmd->symoff )
+ throw "malformed mach-o image: symbol table size wraps";
+ if ( symTabCmd->symoff + symbolsSize > symTabCmd->stroff )
+ throw "malformed mach-o image: symbol table overlaps symbol strings";
+ if ( symTabCmd->stroff + symTabCmd->strsize < symTabCmd->stroff )
+ throw "malformed mach-o image: symbol string size wraps";
+ if ( symTabCmd->stroff + symTabCmd->strsize > linkeditFileOffsetEnd ) {
+ // <rdar://problem/24220313> let old apps overflow as long as it stays within mapped page
+ if ( context.strictMachORequired || (symTabCmd->stroff + symTabCmd->strsize > ((linkeditFileOffsetEnd + 4095) & (-4096))) )
+ throw "malformed mach-o image: symbol strings overrun __LINKEDIT";
+ }
+ // validate indirect symbol table
+ if ( dynSymbTabCmd->nindirectsyms != 0 ) {
+ if ( dynSymbTabCmd->indirectsymoff < linkeditFileOffsetStart )
+ throw "malformed mach-o image: indirect symbol table underruns __LINKEDIT";
+ if ( dynSymbTabCmd->nindirectsyms > 0x10000000 )
+ throw "malformed mach-o image: indirect symbol table too large";
+ uint32_t indirectTableSize = dynSymbTabCmd->nindirectsyms * sizeof(uint32_t);
+ if ( indirectTableSize > linkeditSegCmd->filesize )
+ throw "malformed mach-o image: indirect symbol table overruns __LINKEDIT";
+ if ( dynSymbTabCmd->indirectsymoff + indirectTableSize < dynSymbTabCmd->indirectsymoff )
+ throw "malformed mach-o image: indirect symbol table size wraps";
+ if ( context.strictMachORequired && (dynSymbTabCmd->indirectsymoff + indirectTableSize > symTabCmd->stroff) )
+ throw "malformed mach-o image: indirect symbol table overruns string pool";
+ }
+ if ( (dynSymbTabCmd->nlocalsym > symTabCmd->nsyms) || (dynSymbTabCmd->ilocalsym > symTabCmd->nsyms) )
+ throw "malformed mach-o image: indirect symbol table local symbol count exceeds total symbols";
+ if ( dynSymbTabCmd->ilocalsym + dynSymbTabCmd->nlocalsym < dynSymbTabCmd->ilocalsym )
+ throw "malformed mach-o image: indirect symbol table local symbol count wraps";
+ if ( (dynSymbTabCmd->nextdefsym > symTabCmd->nsyms) || (dynSymbTabCmd->iextdefsym > symTabCmd->nsyms) )
+ throw "malformed mach-o image: indirect symbol table extern symbol count exceeds total symbols";
+ if ( dynSymbTabCmd->iextdefsym + dynSymbTabCmd->nextdefsym < dynSymbTabCmd->iextdefsym )
+ throw "malformed mach-o image: indirect symbol table extern symbol count wraps";
+ if ( (dynSymbTabCmd->nundefsym > symTabCmd->nsyms) || (dynSymbTabCmd->iundefsym > symTabCmd->nsyms) )
+ throw "malformed mach-o image: indirect symbol table undefined symbol count exceeds total symbols";
+ if ( dynSymbTabCmd->iundefsym + dynSymbTabCmd->nundefsym < dynSymbTabCmd->iundefsym )
+ throw "malformed mach-o image: indirect symbol table undefined symbol count wraps";
+ }
+
+
+ // fSegmentsArrayCount is only 8-bits
+ if ( *segCount > 255 )
+ dyld::throwf("malformed mach-o image: more than 255 segments in %s", path);
+
+ // fSegmentsArrayCount is only 8-bits
+ if ( *libCount > 4095 )
+ dyld::throwf("malformed mach-o image: more than 4095 dependent libraries in %s", path);
+
+ if ( needsAddedLibSystemDepency(*libCount, mh) )
+ *libCount = 1;
+}
+
+
+
+// create image for main executable
+ImageLoader* ImageLoaderMachO::instantiateMainExecutable(const macho_header* mh, uintptr_t slide, const char* path, const LinkContext& context)
+{
+ //dyld::log("ImageLoader=%ld, ImageLoaderMachO=%ld, ImageLoaderMachOClassic=%ld, ImageLoaderMachOCompressed=%ld\n",
+ // sizeof(ImageLoader), sizeof(ImageLoaderMachO), sizeof(ImageLoaderMachOClassic), sizeof(ImageLoaderMachOCompressed));
+ bool compressed;
+ unsigned int segCount;
+ unsigned int libCount;
+ const linkedit_data_command* codeSigCmd;
+ const encryption_info_command* encryptCmd;
+ sniffLoadCommands(mh, path, false, &compressed, &segCount, &libCount, context, &codeSigCmd, &encryptCmd);
+ // instantiate concrete class based on content of load commands
+ if ( compressed )
+ return ImageLoaderMachOCompressed::instantiateMainExecutable(mh, slide, path, segCount, libCount, context);
+ else
+#if SUPPORT_CLASSIC_MACHO
+ return ImageLoaderMachOClassic::instantiateMainExecutable(mh, slide, path, segCount, libCount, context);
+#else
+ throw "missing LC_DYLD_INFO load command";
+#endif
+}
+
+
+// create image by mapping in a mach-o file
+ImageLoader* ImageLoaderMachO::instantiateFromFile(const char* path, int fd, const uint8_t firstPages[], size_t firstPagesSize, uint64_t offsetInFat,
+ uint64_t lenInFat, const struct stat& info, const LinkContext& context)
+{
+ bool compressed;
+ unsigned int segCount;
+ unsigned int libCount;
+ const linkedit_data_command* codeSigCmd;
+ const encryption_info_command* encryptCmd;
+ sniffLoadCommands((const macho_header*)firstPages, path, false, &compressed, &segCount, &libCount, context, &codeSigCmd, &encryptCmd);
+ // instantiate concrete class based on content of load commands
+ if ( compressed )
+ return ImageLoaderMachOCompressed::instantiateFromFile(path, fd, firstPages, firstPagesSize, offsetInFat, lenInFat, info, segCount, libCount, codeSigCmd, encryptCmd, context);
+ else
+#if SUPPORT_CLASSIC_MACHO
+ return ImageLoaderMachOClassic::instantiateFromFile(path, fd, firstPages, firstPagesSize, offsetInFat, lenInFat, info, segCount, libCount, codeSigCmd, context);
+#else
+ throw "missing LC_DYLD_INFO load command";
+#endif
+}
+
+// create image by using cached mach-o file
+ImageLoader* ImageLoaderMachO::instantiateFromCache(const macho_header* mh, const char* path, long slide, const struct stat& info, const LinkContext& context)
+{
+ // instantiate right concrete class
+ bool compressed;
+ unsigned int segCount;
+ unsigned int libCount;
+ const linkedit_data_command* codeSigCmd;
+ const encryption_info_command* encryptCmd;
+ sniffLoadCommands(mh, path, true, &compressed, &segCount, &libCount, context, &codeSigCmd, &encryptCmd);
+ // instantiate concrete class based on content of load commands
+ if ( compressed )
+ return ImageLoaderMachOCompressed::instantiateFromCache(mh, path, slide, info, segCount, libCount, context);
+ else
+#if SUPPORT_CLASSIC_MACHO
+ return ImageLoaderMachOClassic::instantiateFromCache(mh, path, slide, info, segCount, libCount, context);
+#else
+ throw "missing LC_DYLD_INFO load command";
+#endif
+}
+
+// create image by copying an in-memory mach-o file
+ImageLoader* ImageLoaderMachO::instantiateFromMemory(const char* moduleName, const macho_header* mh, uint64_t len, const LinkContext& context)
+{
+ bool compressed;
+ unsigned int segCount;
+ unsigned int libCount;
+ const linkedit_data_command* sigcmd;
+ const encryption_info_command* encryptCmd;
+ sniffLoadCommands(mh, moduleName, false, &compressed, &segCount, &libCount, context, &sigcmd, &encryptCmd);
+ // instantiate concrete class based on content of load commands
+ if ( compressed )
+ return ImageLoaderMachOCompressed::instantiateFromMemory(moduleName, mh, len, segCount, libCount, context);
+ else
+#if SUPPORT_CLASSIC_MACHO
+ return ImageLoaderMachOClassic::instantiateFromMemory(moduleName, mh, len, segCount, libCount, context);
+#else
+ throw "missing LC_DYLD_INFO load command";
+#endif
+}
+
+
+int ImageLoaderMachO::crashIfInvalidCodeSignature()
+{
+ // Now that segments are mapped in, try reading from first executable segment.
+ // If code signing is enabled the kernel will validate the code signature
+ // when paging in, and kill the process if invalid.
+ for(unsigned int i=0; i < fSegmentsCount; ++i) {
+ if ( (segFileOffset(i) == 0) && (segFileSize(i) != 0) ) {
+ // return read value to ensure compiler does not optimize away load
+ int* p = (int*)segActualLoadAddress(i);
+ return *p;
+ }
+ }
+ return 0;
+}
+
+
+void ImageLoaderMachO::parseLoadCmds(const LinkContext& context)
+{
+ // now that segments are mapped in, get real fMachOData, fLinkEditBase, and fSlide
+ for(unsigned int i=0; i < fSegmentsCount; ++i) {
+ // set up pointer to __LINKEDIT segment
+ if ( strcmp(segName(i),"__LINKEDIT") == 0 ) {
+ #if !__MAC_OS_X_VERSION_MIN_REQUIRED
+ // <rdar://problem/42419336> historically, macOS never did this check
+ if ( segFileOffset(i) > fCoveredCodeLength )
+ dyld::throwf("cannot load '%s' (segment outside of code signature)", this->getShortName());
+ #endif
+ fLinkEditBase = (uint8_t*)(segActualLoadAddress(i) - segFileOffset(i));
+ }
+#if TEXT_RELOC_SUPPORT
+ // __TEXT segment always starts at beginning of file and contains mach_header and load commands
+ if ( segExecutable(i) ) {
+ if ( segHasRebaseFixUps(i) && (fSlide != 0) )
+ fTextSegmentRebases = true;
+ if ( segHasBindFixUps(i) )
+ fTextSegmentBinds = true;
+ }
+#endif
+#if __i386__
+ if ( segIsReadOnlyImport(i) )
+ fReadOnlyImportSegment = true;
+#endif
+ // some segment always starts at beginning of file and contains mach_header and load commands
+ if ( (segFileOffset(i) == 0) && (segFileSize(i) != 0) ) {
+ fMachOData = (uint8_t*)(segActualLoadAddress(i));
+ }
+ }
+
+ // keep count of prebound images with weak exports
+ if ( this->participatesInCoalescing() ) {
+ ++fgImagesRequiringCoalescing;
+ fRegisteredAsRequiresCoalescing = true;
+ if ( this->hasCoalescedExports() )
+ ++fgImagesHasWeakDefinitions;
+ }
+
+ // keep count of images used in shared cache
+ if ( fInSharedCache )
+ ++fgImagesUsedFromSharedCache;
+
+ // walk load commands (mapped in at start of __TEXT segment)
+ const dyld_info_command* dyldInfo = NULL;
+ const macho_nlist* symbolTable = NULL;
+ const char* symbolTableStrings = NULL;
+ const struct load_command* firstUnknownCmd = NULL;
+ const struct version_min_command* minOSVersionCmd = NULL;
+ const dysymtab_command* dynSymbolTable = NULL;
+ const uint32_t cmd_count = ((macho_header*)fMachOData)->ncmds;
+ const struct load_command* const cmds = (struct load_command*)&fMachOData[sizeof(macho_header)];
+ const struct load_command* cmd = cmds;
+ for (uint32_t i = 0; i < cmd_count; ++i) {
+ switch (cmd->cmd) {
+ case LC_SYMTAB:
+ {
+ const struct symtab_command* symtab = (struct symtab_command*)cmd;
+ symbolTableStrings = (const char*)&fLinkEditBase[symtab->stroff];
+ symbolTable = (macho_nlist*)(&fLinkEditBase[symtab->symoff]);
+ }
+ break;
+ case LC_DYSYMTAB:
+ dynSymbolTable = (struct dysymtab_command*)cmd;
+ break;
+ case LC_SUB_UMBRELLA:
+ fHasSubUmbrella = true;
+ break;
+ case LC_SUB_FRAMEWORK:
+ fInUmbrella = true;
+ break;
+ case LC_SUB_LIBRARY:
+ fHasSubLibraries = true;
+ break;
+ case LC_ROUTINES_COMMAND:
+ fHasDashInit = true;
+ break;
+ case LC_DYLD_INFO:
+ case LC_DYLD_INFO_ONLY:
+ dyldInfo = (struct dyld_info_command*)cmd;
+ break;
+ case LC_SEGMENT_COMMAND:
+ {
+ const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
+ const bool isTextSeg = (strcmp(seg->segname, "__TEXT") == 0);
+ #if __i386__ && __MAC_OS_X_VERSION_MIN_REQUIRED
+ const bool isObjCSeg = (strcmp(seg->segname, "__OBJC") == 0);
+ if ( isObjCSeg )
+ fNotifyObjC = true;
+ #else
+ const bool isDataSeg = (strncmp(seg->segname, "__DATA", 6) == 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 )
+ fHasInitializers = true;
+ else if ( type == S_MOD_TERM_FUNC_POINTERS )
+ fHasTerminators = true;
+ else if ( type == S_DTRACE_DOF )
+ fHasDOFSections = true;
+ else if ( isTextSeg && (strcmp(sect->sectname, "__eh_frame") == 0) )
+ fEHFrameSectionOffset = (uint32_t)((uint8_t*)sect - fMachOData);
+ else if ( isTextSeg && (strcmp(sect->sectname, "__unwind_info") == 0) )
+ fUnwindInfoSectionOffset = (uint32_t)((uint8_t*)sect - fMachOData);
+
+ #if __i386__ && __MAC_OS_X_VERSION_MIN_REQUIRED
+ else if ( isObjCSeg ) {
+ if ( strcmp(sect->sectname, "__image_info") == 0 ) {
+ const uint32_t* imageInfo = (uint32_t*)(sect->addr + fSlide);
+ uint32_t flags = imageInfo[1];
+ if ( (flags & 4) && (((macho_header*)fMachOData)->filetype != MH_EXECUTE) )
+ dyld::throwf("cannot load '%s' because Objective-C garbage collection is not supported", getPath());
+ }
+ else if ( ((macho_header*)fMachOData)->filetype == MH_DYLIB ) {
+ fRetainForObjC = true;
+ }
+ }
+ #else
+ else if ( isDataSeg && (strncmp(sect->sectname, "__objc_imageinfo", 16) == 0) ) {
+ #if __MAC_OS_X_VERSION_MIN_REQUIRED
+ const uint32_t* imageInfo = (uint32_t*)(sect->addr + fSlide);
+ uint32_t flags = imageInfo[1];
+ if ( (flags & 4) && (((macho_header*)fMachOData)->filetype != MH_EXECUTE) )
+ dyld::throwf("cannot load '%s' because Objective-C garbage collection is not supported", getPath());
+ #endif
+ fNotifyObjC = true;
+ }
+ else if ( isDataSeg && (strncmp(sect->sectname, "__objc_", 7) == 0) && (((macho_header*)fMachOData)->filetype == MH_DYLIB) )
+ fRetainForObjC = true;
+ #endif
+ }
+ }
+ break;
+ case LC_TWOLEVEL_HINTS:
+ // no longer supported
+ break;
+ case LC_ID_DYLIB:
+ {
+ fDylibIDOffset = (uint32_t)((uint8_t*)cmd - fMachOData);
+ }
+ break;
+ case LC_RPATH:
+ case LC_LOAD_WEAK_DYLIB:
+ case LC_REEXPORT_DYLIB:
+ case LC_LOAD_UPWARD_DYLIB:
+ case LC_MAIN:
+ // do nothing, just prevent LC_REQ_DYLD exception from occuring
+ break;
+ case LC_VERSION_MIN_MACOSX:
+ case LC_VERSION_MIN_IPHONEOS:
+ case LC_VERSION_MIN_TVOS:
+ case LC_VERSION_MIN_WATCHOS:
+ minOSVersionCmd = (version_min_command*)cmd;
+ break;
+ default:
+ if ( (cmd->cmd & LC_REQ_DYLD) != 0 ) {
+ if ( firstUnknownCmd == NULL )
+ firstUnknownCmd = cmd;
+ }
+ break;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ if ( firstUnknownCmd != NULL ) {
+ if ( minOSVersionCmd != NULL ) {
+ dyld::throwf("cannot load '%s' because it was built for OS version %u.%u (load command 0x%08X is unknown)",
+ this->getShortName(),
+ minOSVersionCmd->version >> 16, ((minOSVersionCmd->version >> 8) & 0xff),
+ firstUnknownCmd->cmd);
+ }
+ else {
+ dyld::throwf("cannot load '%s' (load command 0x%08X is unknown)", this->getShortName(), firstUnknownCmd->cmd);
+ }
+ }
+
+
+ if ( dyldInfo != NULL )
+ this->setDyldInfo(dyldInfo);
+ if ( symbolTable != NULL)
+ this->setSymbolTableInfo(symbolTable, symbolTableStrings, dynSymbolTable);
+
+}
+
+// don't do this work in destructor because we need object to be full subclass
+// for UnmapSegments() to work
+void ImageLoaderMachO::destroy()
+{
+ // update count of images with weak exports
+ if ( fRegisteredAsRequiresCoalescing ) {
+ --fgImagesRequiringCoalescing;
+ if ( this->hasCoalescedExports() )
+ --fgImagesHasWeakDefinitions;
+ }
+
+ // keep count of images used in shared cache
+ if ( fInSharedCache )
+ --fgImagesUsedFromSharedCache;
+
+ // unmap image when done
+ UnmapSegments();
+}
+
+
+unsigned int ImageLoaderMachO::segmentCount() const
+{
+ return fSegmentsCount;
+}
+
+
+const macho_segment_command* ImageLoaderMachO::segLoadCommand(unsigned int segIndex) const
+{
+ uint32_t* lcOffsets = this->segmentCommandOffsets();
+ uint32_t lcOffset = lcOffsets[segIndex];
+ return (macho_segment_command*)(&fMachOData[lcOffset]);
+}
+
+const char* ImageLoaderMachO::segName(unsigned int segIndex) const
+{
+ return segLoadCommand(segIndex)->segname;
+}
+
+
+uintptr_t ImageLoaderMachO::segSize(unsigned int segIndex) const
+{
+ return segLoadCommand(segIndex)->vmsize;
+}
+
+
+uintptr_t ImageLoaderMachO::segFileSize(unsigned int segIndex) const
+{
+ return segLoadCommand(segIndex)->filesize;
+}
+
+
+bool ImageLoaderMachO::segHasTrailingZeroFill(unsigned int segIndex)
+{
+ return ( segWriteable(segIndex) && (segSize(segIndex) > segFileSize(segIndex)) );
+}
+
+
+uintptr_t ImageLoaderMachO::segFileOffset(unsigned int segIndex) const
+{
+ return segLoadCommand(segIndex)->fileoff;
+}
+
+
+bool ImageLoaderMachO::segReadable(unsigned int segIndex) const
+{
+ return ( (segLoadCommand(segIndex)->initprot & VM_PROT_READ) != 0);
+}
+
+
+bool ImageLoaderMachO::segWriteable(unsigned int segIndex) const
+{
+ return ( (segLoadCommand(segIndex)->initprot & VM_PROT_WRITE) != 0);
+}
+
+
+bool ImageLoaderMachO::segExecutable(unsigned int segIndex) const
+{
+ return ( (segLoadCommand(segIndex)->initprot & VM_PROT_EXECUTE) != 0);
+}
+
+
+bool ImageLoaderMachO::segUnaccessible(unsigned int segIndex) const
+{
+ return (segLoadCommand(segIndex)->initprot == 0);
+}
+
+bool ImageLoaderMachO::segHasPreferredLoadAddress(unsigned int segIndex) const
+{
+ return (segLoadCommand(segIndex)->vmaddr != 0);
+}
+
+uintptr_t ImageLoaderMachO::segPreferredLoadAddress(unsigned int segIndex) const
+{
+ return segLoadCommand(segIndex)->vmaddr;
+}
+
+uintptr_t ImageLoaderMachO::segActualLoadAddress(unsigned int segIndex) const
+{
+ return segLoadCommand(segIndex)->vmaddr + fSlide;
+}
+
+
+uintptr_t ImageLoaderMachO::segActualEndAddress(unsigned int segIndex) const
+{
+ return segActualLoadAddress(segIndex) + segSize(segIndex);
+}
+
+bool ImageLoaderMachO::segHasRebaseFixUps(unsigned int segIndex) const
+{
+#if TEXT_RELOC_SUPPORT
+ // scan sections for fix-up bit
+ const macho_segment_command* segCmd = segLoadCommand(segIndex);
+ const struct macho_section* const sectionsStart = (struct macho_section*)((char*)segCmd + sizeof(struct macho_segment_command));
+ const struct macho_section* const sectionsEnd = §ionsStart[segCmd->nsects];
+ for (const struct macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
+ if ( (sect->flags & S_ATTR_LOC_RELOC) != 0 )
+ return true;
+ }
+#endif
+ return false;
+}
+
+bool ImageLoaderMachO::segHasBindFixUps(unsigned int segIndex) const
+{
+#if TEXT_RELOC_SUPPORT
+ // scan sections for fix-up bit
+ const macho_segment_command* segCmd = segLoadCommand(segIndex);
+ const struct macho_section* const sectionsStart = (struct macho_section*)((char*)segCmd + sizeof(struct macho_segment_command));
+ const struct macho_section* const sectionsEnd = §ionsStart[segCmd->nsects];
+ for (const struct macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
+ if ( (sect->flags & S_ATTR_EXT_RELOC) != 0 )
+ return true;
+ }
+#endif
+ return false;
+}
+
+#if __i386__
+bool ImageLoaderMachO::segIsReadOnlyImport(unsigned int segIndex) const
+{
+ const macho_segment_command* segCmd = segLoadCommand(segIndex);
+ return ( (segCmd->initprot & VM_PROT_EXECUTE)
+ && ((segCmd->initprot & VM_PROT_WRITE) == 0)
+ && (strcmp(segCmd->segname, "__IMPORT") == 0) );
+}
+#endif
+
+
+void ImageLoaderMachO::UnmapSegments()
+{
+ // usually unmap image when done
+ if ( ! this->leaveMapped() && (this->getState() >= dyld_image_state_mapped) ) {
+ // unmap TEXT segment last because it contains load command being inspected
+ unsigned int textSegmentIndex = 0;
+ for(unsigned int i=0; i < fSegmentsCount; ++i) {
+ //dyld::log("unmap %s at 0x%08lX\n", seg->getName(), seg->getActualLoadAddress(this));
+ if ( (segFileOffset(i) == 0) && (segFileSize(i) != 0) ) {
+ textSegmentIndex = i;
+ }
+ else {
+ // update stats
+ --ImageLoader::fgTotalSegmentsMapped;
+ ImageLoader::fgTotalBytesMapped -= segSize(i);
+ munmap((void*)segActualLoadAddress(i), segSize(i));
+ }
+ }
+ // now unmap TEXT
+ --ImageLoader::fgTotalSegmentsMapped;
+ ImageLoader::fgTotalBytesMapped -= segSize(textSegmentIndex);
+ munmap((void*)segActualLoadAddress(textSegmentIndex), segSize(textSegmentIndex));
+ }
+}
+
+
+// prefetch __DATA/__OBJC pages during launch, but not for dynamically loaded code
+void ImageLoaderMachO::preFetchDATA(int fd, uint64_t offsetInFat, const LinkContext& context)
+{
+ if ( context.linkingMainExecutable ) {
+ for(unsigned int i=0, e=segmentCount(); i < e; ++i) {
+ if ( segWriteable(i) && (segFileSize(i) > 0) ) {
+ // prefetch writable segment that have mmap'ed regions
+ radvisory advice;
+ advice.ra_offset = offsetInFat + segFileOffset(i);
+ advice.ra_count = (int)segFileSize(i);
+ // limit prefetch to 1MB (256 pages)
+ if ( advice.ra_count > 1024*1024 )
+ advice.ra_count = 1024*1024;
+ // don't prefetch single pages, let them fault in
+ fgTotalBytesPreFetched += advice.ra_count;
+ fcntl(fd, F_RDADVISE, &advice);
+ if ( context.verboseMapping ) {
+ dyld::log("%18s prefetching 0x%0lX -> 0x%0lX\n",
+ segName(i), segActualLoadAddress(i), segActualLoadAddress(i)+advice.ra_count-1);
+ }
+ }
+ }
+ }
+}
+
+
+bool ImageLoaderMachO::segmentsMustSlideTogether() const
+{
+ return true;
+}
+
+bool ImageLoaderMachO::segmentsCanSlide() const
+{
+ return (this->isDylib() || this->isBundle() || this->isPositionIndependentExecutable());
+}
+
+bool ImageLoaderMachO::isBundle() const
+{
+ const macho_header* mh = (macho_header*)fMachOData;
+ return ( mh->filetype == MH_BUNDLE );
+}
+
+bool ImageLoaderMachO::isDylib() const
+{
+ const macho_header* mh = (macho_header*)fMachOData;
+ return ( mh->filetype == MH_DYLIB );
+}
+
+bool ImageLoaderMachO::isExecutable() const
+{
+ const macho_header* mh = (macho_header*)fMachOData;
+ return ( mh->filetype == MH_EXECUTE );
+}
+
+bool ImageLoaderMachO::isPositionIndependentExecutable() const
+{
+ const macho_header* mh = (macho_header*)fMachOData;
+ return ( (mh->filetype == MH_EXECUTE) && ((mh->flags & MH_PIE) != 0) );
+}
+
+
+bool ImageLoaderMachO::forceFlat() const
+{
+ const macho_header* mh = (macho_header*)fMachOData;
+ return ( (mh->flags & MH_FORCE_FLAT) != 0 );
+}
+
+bool ImageLoaderMachO::usesTwoLevelNameSpace() const
+{
+ const macho_header* mh = (macho_header*)fMachOData;
+ return ( (mh->flags & MH_TWOLEVEL) != 0 );
+}
+
+bool ImageLoaderMachO::isPrebindable() const
+{
+ const macho_header* mh = (macho_header*)fMachOData;
+ return ( (mh->flags & MH_PREBOUND) != 0 );
+}
+
+bool ImageLoaderMachO::hasCoalescedExports() const
+{
+ const macho_header* mh = (macho_header*)fMachOData;
+ return ( (mh->flags & MH_WEAK_DEFINES) != 0 );
+}
+
+bool ImageLoaderMachO::hasReferencesToWeakSymbols() const
+{
+ const macho_header* mh = (macho_header*)fMachOData;
+ return ( (mh->flags & MH_BINDS_TO_WEAK) != 0 );
+}
+
+bool ImageLoaderMachO::participatesInCoalescing() const
+{
+ const macho_header* mh = (macho_header*)fMachOData;
+ // if image is loaded with RTLD_LOCAL, then its symbols' visibility
+ // is reduced and it can't coalesce with other images
+ if ( this->hasHiddenExports() )
+ return false;
+ return ( (mh->flags & (MH_WEAK_DEFINES|MH_BINDS_TO_WEAK)) != 0 );
+}
+
+
+
+void ImageLoaderMachO::setSlide(intptr_t slide)
+{
+ fSlide = slide;
+}
+
+void ImageLoaderMachO::loadCodeSignature(const struct linkedit_data_command* codeSigCmd, int fd, uint64_t offsetInFatFile, const LinkContext& context)
+{
+ dyld3::ScopedTimer(DBG_DYLD_TIMING_ATTACH_CODESIGNATURE, 0, 0, 0);
+ // if dylib being loaded has no code signature load command
+ if ( codeSigCmd == NULL) {
+ disableCoverageCheck();
+ }
+ else {
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
+ // <rdar://problem/13622786> ignore code signatures in binaries built with pre-10.9 tools
+ if ( this->sdkVersion() < DYLD_MACOSX_VERSION_10_9 ) {
+ disableCoverageCheck();
+ return;
+ }
+#endif
+
+ fsignatures_t siginfo;
+ siginfo.fs_file_start=offsetInFatFile; // start of mach-o slice in fat file
+ siginfo.fs_blob_start=(void*)(long)(codeSigCmd->dataoff); // start of CD in mach-o file
+ siginfo.fs_blob_size=codeSigCmd->datasize; // size of CD
+ int result = fcntl(fd, F_ADDFILESIGS_RETURN, &siginfo);
+
+#if TARGET_IPHONE_SIMULATOR
+ // rdar://problem/18759224> check range covered by the code directory after loading
+ // Attempt to fallback only if we are in the simulator
+
+ if ( result == -1 ) {
+ result = fcntl(fd, F_ADDFILESIGS, &siginfo);
+ siginfo.fs_file_start = codeSigCmd->dataoff;
+ }
+#endif
+
+ if ( result == -1 ) {
+ if ( (errno == EPERM) || (errno == EBADEXEC) )
+ dyld::throwf("code signature invalid for '%s'\n", this->getPath());
+ if ( context.verboseCodeSignatures )
+ dyld::log("dyld: Failed registering code signature for %s, errno=%d\n", this->getPath(), errno);
+ siginfo.fs_file_start = UINT64_MAX;
+ } else if ( context.verboseCodeSignatures ) {
+ dyld::log("dyld: Registered code signature for %s\n", this->getPath());
+ }
+ fCoveredCodeLength = siginfo.fs_file_start;
+ }
+
+ {
+ fchecklv checkInfo;
+ char messageBuffer[512];
+ messageBuffer[0] = '\0';
+ checkInfo.lv_file_start = offsetInFatFile;
+ checkInfo.lv_error_message_size = sizeof(messageBuffer);
+ checkInfo.lv_error_message = messageBuffer;
+ int res = fcntl(fd, F_CHECK_LV, &checkInfo);
+ if ( res == -1 ) {
+ dyld::throwf("code signature in (%s) not valid for use in process using Library Validation: %s", this->getPath(), messageBuffer);
+ }
+ }
+}
+
+void ImageLoaderMachO::validateFirstPages(const struct linkedit_data_command* codeSigCmd, int fd, const uint8_t *fileData, size_t lenFileData, off_t offsetInFat, const LinkContext& context)
+{
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
+ // rdar://problem/21839703> 15A226d: dyld crashes in mageLoaderMachO::validateFirstPages during dlopen() after encountering an mmap failure
+ // We need to ignore older code signatures because they will be bad.
+ if ( this->sdkVersion() < DYLD_MACOSX_VERSION_10_9 ) {
+ return;
+ }
+#endif
+ if (codeSigCmd != NULL) {
+ void *fdata = xmmap(NULL, lenFileData, PROT_READ, MAP_SHARED, fd, offsetInFat);
+ if ( fdata == MAP_FAILED ) {
+ int errnoCopy = errno;
+ if ( errnoCopy == EPERM ) {
+ if ( dyld::sandboxBlockedMmap(getPath()) )
+ dyld::throwf("file system sandbox blocked mmap() of '%s'", getPath());
+ else
+ dyld::throwf("code signing blocked mmap() of '%s'", getPath());
+ }
+ else
+ dyld::throwf("mmap() errno=%d validating first page of '%s'", errnoCopy, getPath());
+ }
+ if ( memcmp(fdata, fileData, lenFileData) != 0 )
+ dyld::throwf("mmap() page compare failed for '%s'", getPath());
+ munmap(fdata, lenFileData);
+ }
+}
+
+
+const char* ImageLoaderMachO::getInstallPath() const
+{
+ if ( fDylibIDOffset != 0 ) {
+ const dylib_command* dylibID = (dylib_command*)(&fMachOData[fDylibIDOffset]);
+ return (char*)dylibID + dylibID->dylib.name.offset;
+ }
+ return NULL;
+}
+
+void ImageLoaderMachO::registerInterposing(const LinkContext& context)
+{
+ // mach-o files advertise interposing by having a __DATA __interpose section
+ struct InterposeData { uintptr_t replacement; uintptr_t replacee; };
+ 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_INTERPOSING) || ((strcmp(sect->sectname, "__interpose") == 0) && (strcmp(seg->segname, "__DATA") == 0)) ) {
+ // <rdar://problem/23929217> Ensure section is within segment
+ if ( (sect->addr < seg->vmaddr) || (sect->addr+sect->size > seg->vmaddr+seg->vmsize) || (sect->addr+sect->size < sect->addr) )
+ dyld::throwf("interpose section has malformed address range for %s\n", this->getPath());
+ const InterposeData* interposeArray = (InterposeData*)(sect->addr + fSlide);
+ const size_t count = sect->size / sizeof(InterposeData);
+ for (size_t j=0; j < count; ++j) {
+ ImageLoader::InterposeTuple tuple;
+ tuple.replacement = interposeArray[j].replacement;
+ tuple.neverImage = this;
+ tuple.onlyImage = NULL;
+ tuple.replacee = interposeArray[j].replacee;
+ // <rdar://problem/25686570> ignore interposing on a weak function that does not exist
+ if ( tuple.replacee == 0 )
+ continue;
+ // <rdar://problem/7937695> verify that replacement is in this image
+ if ( this->containsAddress((void*)tuple.replacement) ) {
+ // chain to any existing interpositions
+ for (std::vector<InterposeTuple>::iterator it=fgInterposingTuples.begin(); it != fgInterposingTuples.end(); it++) {
+ if ( it->replacee == tuple.replacee ) {
+ tuple.replacee = it->replacement;
+ }
+ }
+ ImageLoader::fgInterposingTuples.push_back(tuple);
+ }
+ }
+ }
+ }
+ }
+ break;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+}
+
+uint32_t ImageLoaderMachO::sdkVersion(const mach_header* mh)
+{
+ const uint32_t cmd_count = mh->ncmds;
+ const struct load_command* const cmds = (struct load_command*)(((char*)mh) + sizeof(macho_header));
+ const struct load_command* cmd = cmds;
+ const struct version_min_command* versCmd;
+ const struct build_version_command* buildVersCmd;
+ for (uint32_t i = 0; i < cmd_count; ++i) {
+ switch ( cmd->cmd ) {
+ case LC_VERSION_MIN_MACOSX:
+ case LC_VERSION_MIN_IPHONEOS:
+ case LC_VERSION_MIN_TVOS:
+ case LC_VERSION_MIN_WATCHOS:
+ versCmd = (version_min_command*)cmd;
+ return versCmd->sdk;
+ case LC_BUILD_VERSION:
+ buildVersCmd = (build_version_command*)cmd;
+ return buildVersCmd->sdk;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ return 0;
+}
+
+uint32_t ImageLoaderMachO::sdkVersion() const
+{
+ return ImageLoaderMachO::sdkVersion(machHeader());
+}
+
+uint32_t ImageLoaderMachO::minOSVersion(const mach_header* mh)
+{
+ const uint32_t cmd_count = mh->ncmds;
+ const struct load_command* const cmds = (struct load_command*)(((char*)mh) + sizeof(macho_header));
+ const struct load_command* cmd = cmds;
+ const struct version_min_command* versCmd;
+ const struct build_version_command* buildVersCmd;
+ for (uint32_t i = 0; i < cmd_count; ++i) {
+ switch ( cmd->cmd ) {
+ case LC_VERSION_MIN_MACOSX:
+ case LC_VERSION_MIN_IPHONEOS:
+ case LC_VERSION_MIN_TVOS:
+ case LC_VERSION_MIN_WATCHOS:
+ versCmd = (version_min_command*)cmd;
+ return versCmd->version;
+ case LC_BUILD_VERSION:
+ buildVersCmd = (build_version_command*)cmd;
+ return buildVersCmd->minos;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ return 0;
+}
+
+uint32_t ImageLoaderMachO::minOSVersion() const
+{
+ return ImageLoaderMachO::minOSVersion(machHeader());
+}
+
+
+void* ImageLoaderMachO::getEntryFromLC_MAIN() 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 (uint32_t i = 0; i < cmd_count; ++i) {
+ if ( cmd->cmd == LC_MAIN ) {
+ entry_point_command* mainCmd = (entry_point_command*)cmd;
+ void* entry = (void*)(mainCmd->entryoff + (char*)fMachOData);
+ // <rdar://problem/8543820&9228031> verify entry point is in image
+ if ( this->containsAddress(entry) )
+ return entry;
+ else
+ throw "LC_MAIN entryoff is out of range";
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ return NULL;
+}
+
+
+void* ImageLoaderMachO::getEntryFromLC_UNIXTHREAD() 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 (uint32_t i = 0; i < cmd_count; ++i) {
+ if ( cmd->cmd == LC_UNIXTHREAD ) {
+ #if __i386__
+ const i386_thread_state_t* registers = (i386_thread_state_t*)(((char*)cmd) + 16);
+ void* entry = (void*)(registers->eip + fSlide);
+ // <rdar://problem/8543820&9228031> verify entry point is in image
+ if ( this->containsAddress(entry) )
+ return entry;
+ #elif __x86_64__
+ const x86_thread_state64_t* registers = (x86_thread_state64_t*)(((char*)cmd) + 16);
+ void* entry = (void*)(registers->rip + fSlide);
+ // <rdar://problem/8543820&9228031> verify entry point is in image
+ if ( this->containsAddress(entry) )
+ return entry;
+ #elif __arm64__ && !__arm64e__
+ // temp support until <rdar://39514191> is fixed
+ const uint64_t* regs64 = (uint64_t*)(((char*)cmd) + 16);
+ void* entry = (void*)(regs64[32] + fSlide); // arm_thread_state64_t.__pc
+ // <rdar://problem/8543820&9228031> verify entry point is in image
+ if ( this->containsAddress(entry) )
+ return entry;
+ #endif
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ throw "no valid entry point";
+}
+
+bool ImageLoaderMachO::needsAddedLibSystemDepency(unsigned int libCount, const macho_header* mh)
+{
+ // <rdar://problem/6357561> ensure that every image depends on something which depends on libSystem
+ if ( libCount > 1 )
+ return false;
+
+ // <rdar://problem/6409800> dyld implicit-libSystem breaks valgrind
+ if ( mh->filetype == MH_EXECUTE )
+ return false;
+
+ bool isNonOSdylib = false;
+ const uint32_t cmd_count = mh->ncmds;
+ const struct load_command* const cmds = (struct load_command*)((uint8_t*)mh+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:
+ case LC_REEXPORT_DYLIB:
+ case LC_LOAD_UPWARD_DYLIB:
+ return false;
+ case LC_ID_DYLIB:
+ {
+ const dylib_command* dylibID = (dylib_command*)cmd;
+ const char* installPath = (char*)cmd + dylibID->dylib.name.offset;
+ // It is OK for OS dylibs (libSystem or libmath or Rosetta shims) to have no dependents
+ // but all other dylibs must depend on libSystem for initialization to initialize libSystem first
+ // <rdar://problem/6497528> rosetta circular dependency spew
+ isNonOSdylib = ( (strncmp(installPath, "/usr/lib/", 9) != 0) && (strncmp(installPath, "/usr/libexec/oah/Shims", 9) != 0) );
+ }
+ break;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ return isNonOSdylib;
+}
+
+
+void ImageLoaderMachO::doGetDependentLibraries(DependentLibraryInfo libs[])
+{
+ if ( needsAddedLibSystemDepency(libraryCount(), (macho_header*)fMachOData) ) {
+ DependentLibraryInfo* lib = &libs[0];
+ lib->name = LIBSYSTEM_DYLIB_PATH;
+ lib->info.checksum = 0;
+ lib->info.minVersion = 0;
+ lib->info.maxVersion = 0;
+ lib->required = false;
+ lib->reExported = false;
+ lib->upward = false;
+ }
+ else {
+ uint32_t index = 0;
+ 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_LOAD_DYLIB:
+ case LC_LOAD_WEAK_DYLIB:
+ case LC_REEXPORT_DYLIB:
+ case LC_LOAD_UPWARD_DYLIB:
+ {
+ const struct dylib_command* dylib = (struct dylib_command*)cmd;
+ DependentLibraryInfo* lib = &libs[index++];
+ lib->name = (char*)cmd + dylib->dylib.name.offset;
+ //lib->name = strdup((char*)cmd + dylib->dylib.name.offset);
+ 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_WEAK_DYLIB);
+ lib->reExported = (cmd->cmd == LC_REEXPORT_DYLIB);
+ lib->upward = (cmd->cmd == LC_LOAD_UPWARD_DYLIB);
+ }
+ break;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ }
+}
+
+ImageLoader::LibraryInfo ImageLoaderMachO::doGetLibraryInfo(const LibraryInfo&)
+{
+ LibraryInfo info;
+ if ( fDylibIDOffset != 0 ) {
+ const dylib_command* dylibID = (dylib_command*)(&fMachOData[fDylibIDOffset]);
+ info.minVersion = dylibID->dylib.compatibility_version;
+ info.maxVersion = dylibID->dylib.current_version;
+ info.checksum = dylibID->dylib.timestamp;
+ }
+ else {
+ info.minVersion = 0;
+ info.maxVersion = 0;
+ info.checksum = 0;
+ }
+ 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 (uint32_t i = 0; i < cmd_count; ++i) {
+ switch (cmd->cmd) {
+ case LC_RPATH:
+ const char* pathToAdd = NULL;
+ const char* path = (char*)cmd + ((struct rpath_command*)cmd)->path.offset;
+ if ( (strncmp(path, "@loader_path", 12) == 0) && ((path[12] == '/') || (path[12] == '\0')) ) {
+ if ( !context.allowAtPaths && (context.mainExecutable == this) ) {
+ dyld::warn("LC_RPATH %s in %s being ignored in restricted 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, &path[12]);
+ pathToAdd = strdup(newRealPath);
+ }
+ }
+ }
+ else if ( (strncmp(path, "@executable_path", 16) == 0) && ((path[16] == '/') || (path[16] == '\0')) ) {
+ if ( !context.allowAtPaths) {
+ dyld::warn("LC_RPATH %s in %s being ignored in restricted 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, &path[16]);
+ pathToAdd = strdup(newRealPath);
+ }
+ }
+ }
+ else if ( (path[0] != '/') && !context.allowAtPaths) {
+ dyld::warn("LC_RPATH %s in %s being ignored in restricted program because it is a relative path\n", path, this->getPath());
+ break;
+ }
+#if SUPPORT_ROOT_PATH
+ else if ( (path[0] == '/') && (context.rootPaths != NULL) ) {
+ // <rdar://problem/5869973> DYLD_ROOT_PATH should apply to LC_RPATH rpaths
+ // DYLD_ROOT_PATH can be a list of paths, but at this point we can only support one, so use first combination that exists
+ bool found = false;
+ for(const char** rp = context.rootPaths; *rp != NULL; ++rp) {
+ char newPath[PATH_MAX];
+ strlcpy(newPath, *rp, PATH_MAX);
+ strlcat(newPath, path, PATH_MAX);
+ struct stat stat_buf;
+ if ( stat(newPath, &stat_buf) != -1 ) {
+ //dyld::log("combined DYLD_ROOT_PATH and LC_RPATH: %s\n", newPath);
+ pathToAdd = strdup(newPath);
+ found = true;
+ break;
+ }
+ }
+ if ( ! found ) {
+ // make copy so that all elements of 'paths' can be freed
+ pathToAdd = strdup(path);
+ }
+ }
+#endif
+ else {
+ // make copy so that all elements of 'paths' can be freed
+ pathToAdd = strdup(path);
+ }
+ if ( pathToAdd != NULL )
+ paths.push_back(pathToAdd);
+ break;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+}
+
+
+bool ImageLoaderMachO::getUUID(uuid_t uuid) 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 (uint32_t i = 0; i < cmd_count; ++i) {
+ switch (cmd->cmd) {
+ case LC_UUID:
+ uuid_command* uc = (uuid_command*)cmd;
+ memcpy(uuid, uc->uuid, 16);
+ return true;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ bzero(uuid, 16);
+ return false;
+}
+
+void ImageLoaderMachO::doRebase(const LinkContext& context)
+{
+ // <rdar://problem/25329861> Delay calling setNeverUnload() until we know this is not for dlopen_preflight()
+ if ( fRetainForObjC )
+ this->setNeverUnload();
+
+ // dylibs with thread local variables cannot be unloaded because there is no way to clean up all threads
+ if ( !this->inSharedCache() && (this->machHeader()->flags & MH_HAS_TLV_DESCRIPTORS) )
+ this->setNeverUnload();
+
+ // if prebound and loaded at prebound address, then no need to rebase
+ 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() ) {
+ dyld::log("dyld: image not prebound, so could not use prebinding in %s\n", this->getPath());
+ }
+ else if ( fSlide != 0 ) {
+ dyld::log("dyld: image slid, so could not use prebinding in %s\n", this->getPath());
+ }
+ else if ( !this->allDependentLibrariesAsWhenPreBound() ) {
+ dyld::log("dyld: dependent libraries changed, so could not use prebinding in %s\n", this->getPath());
+ }
+ else if ( !this->usesTwoLevelNameSpace() ){
+ dyld::log("dyld: image uses flat-namespace so, parts of prebinding ignored %s\n", this->getPath());
+ }
+ else {
+ dyld::log("dyld: environment variable disabled use of prebinding in %s\n", this->getPath());
+ }
+ }
+
+ //dyld::log("slide=0x%08lX for %s\n", slide, this->getPath());
+
+#if PREBOUND_IMAGE_SUPPORT
+ // 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);
+#endif
+
+ // if loaded at preferred address, no rebasing necessary
+ if ( this->fSlide == 0 )
+ return;
+
+#if TEXT_RELOC_SUPPORT
+ // if there are __TEXT fixups, temporarily make __TEXT writable
+ if ( fTextSegmentRebases )
+ this->makeTextSegmentWritable(context, true);
+#endif
+
+ // do actual rebasing
+ this->rebase(context, fSlide);
+
+#if TEXT_RELOC_SUPPORT
+ // if there were __TEXT fixups, restore write protection
+ if ( fTextSegmentRebases )
+ this->makeTextSegmentWritable(context, false);
+
+#endif
+}
+
+#if TEXT_RELOC_SUPPORT
+void ImageLoaderMachO::makeTextSegmentWritable(const LinkContext& context, bool writeable)
+{
+ for(unsigned int i=0; i < fSegmentsCount; ++i) {
+ if ( segExecutable(i) ) {
+ if ( writeable ) {
+ segMakeWritable(i, context);
+ }
+ else {
+ #if !__i386__ && !__x86_64__
+ // some processors require range to be invalidated before it is made executable
+ sys_icache_invalidate((void*)segActualLoadAddress(i), segSize(textSegmentIndex));
+ #endif
+ segProtect(i, context);
+ }
+ }
+ }
+
+}
+#endif
+
+const ImageLoader::Symbol* ImageLoaderMachO::findExportedSymbol(const char* name, bool searchReExports, const char* thisPath, const ImageLoader** foundIn) const
+{
+ // look in this image first
+ const ImageLoader::Symbol* result = this->findShallowExportedSymbol(name, foundIn);
+ if ( result != NULL )
+ return result;
+
+ if ( searchReExports ) {
+ for(unsigned int i=0; i < libraryCount(); ++i){
+ if ( libReExported(i) ) {
+ ImageLoader* image = libImage(i);
+ if ( image != NULL ) {
+ const char* reExPath = libPath(i);
+ result = image->findExportedSymbol(name, searchReExports, reExPath, foundIn);
+ if ( result != NULL )
+ return result;
+ }
+ }
+ }
+ }
+
+
+ return NULL;
+}
+
+
+
+uintptr_t ImageLoaderMachO::getExportedSymbolAddress(const Symbol* sym, const LinkContext& context,
+ const ImageLoader* requestor, bool runResolver, const char* symbolName) const
+{
+ return this->getSymbolAddress(sym, requestor, context, runResolver);
+}
+
+uintptr_t ImageLoaderMachO::getSymbolAddress(const Symbol* sym, const ImageLoader* requestor,
+ const LinkContext& context, bool runResolver) const
+{
+ uintptr_t result = exportedSymbolAddress(context, sym, requestor, runResolver);
+ // check for interposing overrides
+ result = interposedAddress(context, result, requestor);
+ return result;
+}
+
+ImageLoader::DefinitionFlags ImageLoaderMachO::getExportedSymbolInfo(const Symbol* sym) const
+{
+ if ( exportedSymbolIsWeakDefintion(sym) )
+ return kWeakDefinition;
+ else
+ return kNoDefinitionOptions;
+}
+
+const char* ImageLoaderMachO::getExportedSymbolName(const Symbol* sym) const
+{
+ return exportedSymbolName(sym);
+}
+
+uint32_t ImageLoaderMachO::getExportedSymbolCount() const
+{
+ return exportedSymbolCount();
+}
+
+
+const ImageLoader::Symbol* ImageLoaderMachO::getIndexedExportedSymbol(uint32_t index) const
+{
+ return exportedSymbolIndexed(index);
+}
+
+
+uint32_t ImageLoaderMachO::getImportedSymbolCount() const
+{
+ return importedSymbolCount();
+}
+
+
+const ImageLoader::Symbol* ImageLoaderMachO::getIndexedImportedSymbol(uint32_t index) const
+{
+ return importedSymbolIndexed(index);
+}
+
+
+ImageLoader::ReferenceFlags ImageLoaderMachO::getImportedSymbolInfo(const ImageLoader::Symbol* sym) const
+{
+ ImageLoader::ReferenceFlags flags = kNoReferenceOptions;
+ return flags;
+}
+
+
+const char* ImageLoaderMachO::getImportedSymbolName(const ImageLoader::Symbol* sym) const
+{
+ return importedSymbolName(sym);
+}
+
+
+bool ImageLoaderMachO::getSectionContent(const char* segmentName, const char* sectionName, void** start, size_t* length)
+{
+ 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 ( (strcmp(sect->segname, segmentName) == 0) && (strcmp(sect->sectname, sectionName) == 0) ) {
+ *start = (uintptr_t*)(sect->addr + fSlide);
+ *length = sect->size;
+ return true;
+ }
+ }
+ }
+ break;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ *start = NULL;
+ *length = 0;
+ return false;
+}
+
+void ImageLoaderMachO::getUnwindInfo(dyld_unwind_sections* info)
+{
+ info->mh = this->machHeader();
+ info->dwarf_section = 0;
+ info->dwarf_section_length = 0;
+ info->compact_unwind_section = 0;
+ info->compact_unwind_section_length = 0;
+ if ( fEHFrameSectionOffset != 0 ) {
+ const macho_section* sect = (macho_section*)&fMachOData[fEHFrameSectionOffset];
+ info->dwarf_section = (void*)(sect->addr + fSlide);
+ info->dwarf_section_length = sect->size;
+ }
+ if ( fUnwindInfoSectionOffset != 0 ) {
+ const macho_section* sect = (macho_section*)&fMachOData[fUnwindInfoSectionOffset];
+ info->compact_unwind_section = (void*)(sect->addr + fSlide);
+ info->compact_unwind_section_length = sect->size;
+ }
+}
+
+intptr_t ImageLoaderMachO::computeSlide(const mach_header* mh)
+{
+ const uint32_t cmd_count = mh->ncmds;
+ const load_command* const cmds = (load_command*)((char*)mh + sizeof(macho_header));
+ const load_command* cmd = cmds;
+ for (uint32_t i = 0; i < cmd_count; ++i) {
+ if ( cmd->cmd == LC_SEGMENT_COMMAND ) {
+ const macho_segment_command* seg = (macho_segment_command*)cmd;
+ if ( strcmp(seg->segname, "__TEXT") == 0 )
+ return (char*)mh - (char*)(seg->vmaddr);
+ }
+ cmd = (const load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ return 0;
+}
+
+bool ImageLoaderMachO::findSection(const mach_header* mh, const char* segmentName, const char* sectionName, void** sectAddress, size_t* sectSize)
+{
+ const uint32_t cmd_count = mh->ncmds;
+ const load_command* const cmds = (load_command*)((char*)mh + sizeof(macho_header));
+ const load_command* cmd = cmds;
+ for (uint32_t i = 0; i < cmd_count; ++i) {
+ switch (cmd->cmd) {
+ case LC_SEGMENT_COMMAND:
+ {
+ const macho_segment_command* seg = (macho_segment_command*)cmd;
+ const macho_section* const sectionsStart = (macho_section*)((char*)seg + sizeof(macho_segment_command));
+ const macho_section* const sectionsEnd = §ionsStart[seg->nsects];
+ for (const macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
+ if ( (strcmp(sect->segname, segmentName) == 0) && (strcmp(sect->sectname, sectionName) == 0) ) {
+ *sectAddress = (void*)(sect->addr + computeSlide(mh));
+ *sectSize = sect->size;
+ return true;
+ }
+ }
+ }
+ break;
+ }
+ cmd = (const load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ return false;
+}
+
+
+const macho_section* ImageLoaderMachO::findSection(const void* imageInterior) 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;
+ const uintptr_t unslidInteriorAddress = (uintptr_t)imageInterior - this->getSlide();
+ 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;
+ if ( (unslidInteriorAddress >= seg->vmaddr) && (unslidInteriorAddress < (seg->vmaddr+seg->vmsize)) ) {
+ 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->addr <= unslidInteriorAddress) && (unslidInteriorAddress < (sect->addr+sect->size))) {
+ return sect;
+ }
+ }
+ }
+ }
+ break;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ return nullptr;
+}
+
+
+bool ImageLoaderMachO::findSection(const void* imageInterior, const char** segmentName, const char** sectionName, size_t* sectionOffset)
+{
+ if (const struct macho_section* sect = findSection(imageInterior)) {
+ const uintptr_t unslidInteriorAddress = (uintptr_t)imageInterior - this->getSlide();
+ if ( segmentName != NULL )
+ *segmentName = sect->segname;
+ if ( sectionName != NULL )
+ *sectionName = sect->sectname;
+ if ( sectionOffset != NULL )
+ *sectionOffset = unslidInteriorAddress - sect->addr;
+ return true;
+ }
+ return false;
+}
+
+const char* ImageLoaderMachO::libPath(unsigned int index) 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;
+ unsigned count = 0;
+ for (uint32_t i = 0; i < cmd_count; ++i) {
+ switch ( cmd->cmd ) {
+ case LC_LOAD_DYLIB:
+ case LC_LOAD_WEAK_DYLIB:
+ case LC_REEXPORT_DYLIB:
+ case LC_LOAD_UPWARD_DYLIB:
+ if ( index == count ) {
+ const struct dylib_command* dylibCmd = (struct dylib_command*)cmd;
+ return (char*)cmd + dylibCmd->dylib.name.offset;
+ }
+ ++count;
+ break;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+
+ // <rdar://problem/24256354> if image linked with nothing and we implicitly added libSystem.dylib, return that
+ if ( needsAddedLibSystemDepency(libraryCount(), (macho_header*)fMachOData) ) {
+ return LIBSYSTEM_DYLIB_PATH;
+ }
+
+ return NULL;
+}
+
+
+void __attribute__((noreturn)) ImageLoaderMachO::throwSymbolNotFound(const LinkContext& context, const char* symbol,
+ const char* referencedFrom, const char* fromVersMismatch,
+ const char* expectedIn)
+{
+ // record values for possible use by CrashReporter or Finder
+ (*context.setErrorStrings)(DYLD_EXIT_REASON_SYMBOL_MISSING, referencedFrom, expectedIn, symbol);
+ dyld::throwf("Symbol not found: %s\n Referenced from: %s%s\n Expected in: %s\n",
+ symbol, referencedFrom, fromVersMismatch, expectedIn);
+}
+
+const mach_header* ImageLoaderMachO::machHeader() const
+{
+ return (mach_header*)fMachOData;
+}
+
+uintptr_t ImageLoaderMachO::getSlide() const
+{
+ return fSlide;
+}
+
+// hmm. maybe this should be up in ImageLoader??
+const void* ImageLoaderMachO::getEnd() const
+{
+ uintptr_t lastAddress = 0;
+ for(unsigned int i=0; i < fSegmentsCount; ++i) {
+ uintptr_t segEnd = segActualEndAddress(i);
+ if ( strcmp(segName(i), "__UNIXSTACK") != 0 ) {
+ if ( segEnd > lastAddress )
+ lastAddress = segEnd;
+ }
+ }
+ return (const void*)lastAddress;
+}
+
+uintptr_t ImageLoaderMachO::bindLocation(const LinkContext& context, uintptr_t baseVMAddress,
+ uintptr_t location, uintptr_t value,
+ uint8_t type, const char* symbolName,
+ intptr_t addend, const char* inPath, const char* toPath, const char* msg,
+ ExtraBindData *extraBindData, uintptr_t slide)
+{
+ auto logBind = [&]() {
+ if ( !context.verboseBind )
+ return;
+ if ( addend != 0 ) {
+ dyld::log("dyld: %sbind: %s:0x%08lX = %s:%s, *0x%08lX = 0x%08lX + %ld\n",
+ msg, shortName(inPath), (uintptr_t)location,
+ ((toPath != NULL) ? shortName(toPath) : "<missing weak_import>"),
+ symbolName, (uintptr_t)location, value, addend);
+ } else {
+ dyld::log("dyld: %sbind: %s:0x%08lX = %s:%s, *0x%08lX = 0x%08lX\n",
+ msg, shortName(inPath), (uintptr_t)location,
+ ((toPath != NULL) ? shortName(toPath) : "<missing weak_import>"),
+ symbolName, (uintptr_t)location, value);
+ }
+ };
+
+
+#if LOG_BINDINGS
+// dyld::logBindings("%s: %s\n", targetImage->getShortName(), symbolName);
+#endif
+
+ // do actual update
+ uintptr_t* locationToFix = (uintptr_t*)location;
+ uint32_t* loc32;
+ uintptr_t newValue = value+addend;
+ uint32_t value32;
+ switch (type) {
+ case BIND_TYPE_POINTER:
+ logBind();
+ // test first so we don't needless dirty pages
+ if ( *locationToFix != newValue )
+ *locationToFix = newValue;
+ break;
+ case BIND_TYPE_TEXT_ABSOLUTE32:
+ logBind();
+ loc32 = (uint32_t*)locationToFix;
+ value32 = (uint32_t)newValue;
+ if ( *loc32 != value32 )
+ *loc32 = value32;
+ break;
+ case BIND_TYPE_TEXT_PCREL32:
+ logBind();
+ loc32 = (uint32_t*)locationToFix;
+ value32 = (uint32_t)(newValue - (((uintptr_t)locationToFix) + 4));
+ if ( *loc32 != value32 )
+ *loc32 = value32;
+ break;
+ case BIND_TYPE_THREADED_BIND:
+ logBind();
+ // test first so we don't needless dirty pages
+ if ( *locationToFix != newValue )
+ *locationToFix = newValue;
+ break;
+ case BIND_TYPE_THREADED_REBASE: {
+ // Regular pointer which needs to fit in 51-bits of value.
+ // C++ RTTI uses the top bit, so we'll allow the whole top-byte
+ // and the signed-extended bottom 43-bits to be fit in to 51-bits.
+ uint64_t top8Bits = *locationToFix & 0x0007F80000000000ULL;
+ uint64_t bottom43Bits = *locationToFix & 0x000007FFFFFFFFFFULL;
+ uint64_t targetValue = ( top8Bits << 13 ) | (((intptr_t)(bottom43Bits << 21) >> 21) & 0x00FFFFFFFFFFFFFF);
+ newValue = (uintptr_t)(targetValue + slide);
+ if ( context.verboseRebase ) {
+ dyld::log("dyld: rebase: %s:*0x%08lX += 0x%08lX = 0x%08lX\n", shortName(inPath), (uintptr_t)locationToFix, slide, newValue);
+ }
+ *locationToFix = newValue;
+ break;
+ }
+ default:
+ dyld::throwf("bad bind type %d", type);
+ }
+
+ // update statistics
+ ++fgTotalBindFixups;
+
+ return newValue;
+}
+
+
+
+
+
+#if SUPPORT_OLD_CRT_INITIALIZATION
+// first 16 bytes of "start" in crt1.o
+#if __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
+ 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
+extern "C" void stub_binding_helper();
+extern "C" int _dyld_func_lookup(const char* name, void** address);
+
+void ImageLoaderMachO::setupLazyPointerHandler(const LinkContext& context)
+{
+ 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;
+ // There used to be some optimizations to skip this section scan, but we need to handle the
+ // __dyld section in libdyld.dylib, so everything needs to be scanned for now.
+ // <rdar://problem/10910062> CrashTracer: 1,295 crashes in bash at bash: getenv
+ if ( true ) {
+ 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 ( strncmp(seg->segname, "__DATA", 6) == 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 !__arm64__ && !__ARM_ARCH_7K__
+ if ( sect->size > offsetof(DATAdyld, dyldLazyBinder) ) {
+ if ( dd->dyldLazyBinder != (void*)&stub_binding_helper )
+ dd->dyldLazyBinder = (void*)&stub_binding_helper;
+ }
+ #endif // !__arm64__
+ // <rdar://problem/40352925> Add work around for existing apps that have deprecated __dyld section
+ const char* installNm = this->getInstallPath();
+ if ( (mh->filetype != MH_DYLIB) || (installNm == NULL) || (strcmp(installNm, "/usr/lib/system/libdyld.dylib") != 0) ) {
+ #if TARGET_OS_OSX
+ // don't allow macOS apps build with 10.14 or later SDK and targeting 10.8 or later to have a __dyld section
+ if ( (minOSVersion() >= 0x000a0800) && (sdkVersion() >= 0x000a0e00) )
+ dyld::throwf("__dyld section not supported in %s", this->getPath());
+ #endif
+ #if TARGET_OS_IOS || TARGET_OS_TV
+ // don't allow iOS apps build with 12.0 or later SDK to have a __dyld section
+ if ( sdkVersion() >= 0x000c0000 )
+ dyld::throwf("__dyld section not supported in %s", this->getPath());
+ #endif
+ #if TARGET_OS_WATCH
+ if ( sdkVersion() >= 0x00050000 )
+ dyld::throwf("__dyld section not supported in %s", this->getPath());
+ #endif
+ }
+ 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->getEntryFromLC_UNIXTHREAD(), sStandardEntryPointInstructions, 16) != 0 ) {
+ if ( context.verboseInit )
+ dyld::log("dyld: program uses non-standard entry point so delaying running of initializers\n");
+ context.setRunInitialzersOldWay();
+ }
+ #endif
+ }
+ }
+ else if ( mh->filetype == MH_DYLIB ) {
+ const char* installPath = this->getInstallPath();
+ if ( (installPath != NULL) && (strncmp(installPath, "/usr/lib/", 9) == 0) ) {
+ if ( sect->size > offsetof(DATAdyld, vars) ) {
+ // use ProgramVars from libdyld.dylib but tweak mh field to correct value
+ dd->vars.mh = context.mainExecutable->machHeader();
+ context.setNewProgramVars(dd->vars);
+ }
+ }
+ }
+ }
+ else if ( (strcmp(sect->sectname, "__program_vars" ) == 0) && (mh->filetype == MH_EXECUTE) ) {
+ // this is a Mac OS X 10.6 or later main executable
+ struct ProgramVars* pv = (struct ProgramVars*)(sect->addr + fSlide);
+ context.setNewProgramVars(*pv);
+ }
+ }
+ }
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ }
+}
+
+
+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->findShallowExportedSymbol("_NXArgc", NULL);
+ if ( sym != NULL )
+ vars.NXArgcPtr = (int*)this->getExportedSymbolAddress(sym, context, this, false, NULL);
+
+ // lookup _NXArgv
+ sym = this->findShallowExportedSymbol("_NXArgv", NULL);
+ if ( sym != NULL )
+ vars.NXArgvPtr = (const char***)this->getExportedSymbolAddress(sym, context, this, false, NULL);
+
+ // lookup _environ
+ sym = this->findShallowExportedSymbol("_environ", NULL);
+ if ( sym != NULL )
+ vars.environPtr = (const char***)this->getExportedSymbolAddress(sym, context, this, false, NULL);
+
+ // lookup __progname
+ sym = this->findShallowExportedSymbol("___progname", NULL);
+ if ( sym != NULL )
+ vars.__prognamePtr = (const char**)this->getExportedSymbolAddress(sym, context, this, false, NULL);
+
+ 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->getSlide() == 0)) || fInSharedCache)
+ && this->usesTwoLevelNameSpace()
+#if !USES_CHAINED_BINDS
+ && this->allDependentLibrariesAsWhenPreBound()
+#endif
+ ) {
+ // allow environment variables to disable prebinding
+ if ( context.bindFlat )
+ return false;
+ switch ( context.prebindUsage ) {
+ case kUseAllPrebinding:
+ return true;
+ case kUseSplitSegPrebinding:
+ return this->fIsSplitSeg;
+ case kUseAllButAppPredbinding:
+ return (this != context.mainExecutable);
+ case kUseNoPrebinding:
+ return false;
+ }
+ }
+ return false;
+}
+
+static void *stripPointer(void *ptr) {
+#if __has_feature(ptrauth_calls)
+ return __builtin_ptrauth_strip(ptr, ptrauth_key_asia);
+#else
+ return ptr;
+#endif
+}
+
+
+void ImageLoaderMachO::doImageInit(const LinkContext& context)
+{
+ 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 (uint32_t 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 __has_feature(ptrauth_calls)
+ func = (Initializer)__builtin_ptrauth_sign_unauthenticated((void*)func, ptrauth_key_asia, 0);
+#endif
+ // <rdar://problem/8543820&9228031> verify initializers are in image
+ if ( ! this->containsAddress(stripPointer((void*)func)) ) {
+ dyld::throwf("initializer function %p not in mapped image for %s\n", func, this->getPath());
+ }
+ if ( ! dyld::gProcessInfo->libSystemInitialized ) {
+ // <rdar://problem/17973316> libSystem initializer must run first
+ dyld::throwf("-init function in image (%s) that does not link with libSystem.dylib\n", this->getPath());
+ }
+ if ( context.verboseInit )
+ dyld::log("dyld: calling -init function %p in %s\n", func, this->getPath());
+ {
+ dyld3::ScopedTimer(DBG_DYLD_TIMING_STATIC_INITIALIZER, (uint64_t)fMachOData, (uint64_t)func, 0);
+ 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 ( 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 (uint32_t i = 0; i < cmd_count; ++i) {
+ if ( cmd->cmd == LC_SEGMENT_COMMAND ) {
+ const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
+ const struct macho_section* const sectionsStart = (struct macho_section*)((char*)seg + sizeof(struct macho_segment_command));
+ const struct macho_section* const sectionsEnd = §ionsStart[seg->nsects];
+ for (const struct macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
+ const uint8_t type = sect->flags & SECTION_TYPE;
+ if ( type == S_MOD_INIT_FUNC_POINTERS ) {
+ Initializer* inits = (Initializer*)(sect->addr + fSlide);
+ const size_t count = sect->size / sizeof(uintptr_t);
+ // <rdar://problem/23929217> Ensure __mod_init_func section is within segment
+ if ( (sect->addr < seg->vmaddr) || (sect->addr+sect->size > seg->vmaddr+seg->vmsize) || (sect->addr+sect->size < sect->addr) )
+ dyld::throwf("__mod_init_funcs section has malformed address range for %s\n", this->getPath());
+ for (size_t j=0; j < count; ++j) {
+ Initializer func = inits[j];
+ // <rdar://problem/8543820&9228031> verify initializers are in image
+ if ( ! this->containsAddress(stripPointer((void*)func)) ) {
+ dyld::throwf("initializer function %p not in mapped image for %s\n", func, this->getPath());
+ }
+ if ( ! dyld::gProcessInfo->libSystemInitialized ) {
+ // <rdar://problem/17973316> libSystem initializer must run first
+ const char* installPath = getInstallPath();
+ if ( (installPath == NULL) || (strcmp(installPath, LIBSYSTEM_DYLIB_PATH) != 0) )
+ dyld::throwf("initializer in image (%s) that does not link with libSystem.dylib\n", this->getPath());
+ }
+ if ( context.verboseInit )
+ dyld::log("dyld: calling initializer function %p in %s\n", func, this->getPath());
+ bool haveLibSystemHelpersBefore = (dyld::gLibSystemHelpers != NULL);
+ {
+ dyld3::ScopedTimer(DBG_DYLD_TIMING_STATIC_INITIALIZER, (uint64_t)fMachOData, (uint64_t)func, 0);
+ func(context.argc, context.argv, context.envp, context.apple, &context.programVars);
+ }
+ bool haveLibSystemHelpersAfter = (dyld::gLibSystemHelpers != NULL);
+ if ( !haveLibSystemHelpersBefore && haveLibSystemHelpersAfter ) {
+ // now safe to use malloc() and other calls in libSystem.dylib
+ dyld::gProcessInfo->libSystemInitialized = true;
+ }
+ }
+ }
+ }
+ }
+ 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 ) {
+ // <rdar://problem/23929217> Ensure section is within segment
+ if ( (sect->addr < seg->vmaddr) || (sect->addr+sect->size > seg->vmaddr+seg->vmsize) || (sect->addr+sect->size < sect->addr) )
+ dyld::throwf("DOF section has malformed address range for %s\n", this->getPath());
+ 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);
+ }
+ }
+}
+
+
+bool ImageLoaderMachO::doInitialization(const LinkContext& context)
+{
+ CRSetCrashLogMessage2(this->getPath());
+
+ // mach-o has -init and static initializers
+ doImageInit(context);
+ doModInitFunctions(context);
+
+ CRSetCrashLogMessage2(NULL);
+
+ return (fHasDashInit || fHasInitializers);
+}
+
+bool ImageLoaderMachO::needsInitialization()
+{
+ return ( fHasDashInit || fHasInitializers );
+}
+
+
+bool ImageLoaderMachO::needsTermination()
+{
+ return fHasTerminators;
+}
+
+
+void ImageLoaderMachO::doTermination(const LinkContext& context)
+{
+ 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 (uint32_t i = 0; i < cmd_count; ++i) {
+ if ( cmd->cmd == LC_SEGMENT_COMMAND ) {
+ const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
+ const struct macho_section* const sectionsStart = (struct macho_section*)((char*)seg + sizeof(struct macho_segment_command));
+ const struct macho_section* const sectionsEnd = §ionsStart[seg->nsects];
+ for (const struct macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
+ const uint8_t type = sect->flags & SECTION_TYPE;
+ if ( type == S_MOD_TERM_FUNC_POINTERS ) {
+ // <rdar://problem/23929217> Ensure section is within segment
+ if ( (sect->addr < seg->vmaddr) || (sect->addr+sect->size > seg->vmaddr+seg->vmsize) || (sect->addr+sect->size < sect->addr) )
+ dyld::throwf("DOF section has malformed address range for %s\n", this->getPath());
+ Terminator* terms = (Terminator*)(sect->addr + fSlide);
+ const size_t count = sect->size / sizeof(uintptr_t);
+ for (size_t j=count; j > 0; --j) {
+ Terminator func = terms[j-1];
+#if __has_feature(ptrauth_calls)
+ func = (Terminator)__builtin_ptrauth_sign_unauthenticated((void*)func, ptrauth_key_asia, 0);
+#endif
+ // <rdar://problem/8543820&9228031> verify terminators are in image
+ if ( ! this->containsAddress(stripPointer((void*)func)) ) {
+ dyld::throwf("termination function %p not in mapped image for %s\n", func, this->getPath());
+ }
+ if ( context.verboseInit )
+ dyld::log("dyld: calling termination function %p in %s\n", func, this->getPath());
+ func();
+ }
+ }
+ }
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ }
+}
+
+
+void ImageLoaderMachO::printStatisticsDetails(unsigned int imageCount, const InitializerTimingList& timingInfo)
+{
+ ImageLoader::printStatisticsDetails(imageCount, timingInfo);
+ dyld::log("total symbol trie searches: %d\n", fgSymbolTrieSearchs);
+ dyld::log("total symbol table binary searches: %d\n", fgSymbolTableBinarySearchs);
+ dyld::log("total images defining weak symbols: %u\n", fgImagesHasWeakDefinitions);
+ dyld::log("total images using weak symbols: %u\n", fgImagesRequiringCoalescing);
+}
+
+
+intptr_t ImageLoaderMachO::assignSegmentAddresses(const LinkContext& context)
+{
+ // preflight and calculate slide if needed
+ const bool inPIE = (fgNextPIEDylibAddress != 0);
+ intptr_t slide = 0;
+ if ( this->segmentsCanSlide() && this->segmentsMustSlideTogether() ) {
+ bool needsToSlide = false;
+ bool imageHasPreferredLoadAddress = segHasPreferredLoadAddress(0);
+ uintptr_t lowAddr = (unsigned long)(-1);
+ uintptr_t highAddr = 0;
+ for(unsigned int i=0, e=segmentCount(); i < e; ++i) {
+ const uintptr_t segLow = segPreferredLoadAddress(i);
+ const uintptr_t segHigh = dyld_page_round(segLow + segSize(i));
+ if ( segLow < highAddr ) {
+ if ( dyld_page_size > 4096 )
+ dyld::throwf("can't map segments into 16KB pages");
+ else
+ dyld::throwf("overlapping segments");
+ }
+ if ( segLow < lowAddr )
+ lowAddr = segLow;
+ if ( segHigh > highAddr )
+ highAddr = segHigh;
+
+ if ( needsToSlide || !imageHasPreferredLoadAddress || inPIE || !reserveAddressRange(segPreferredLoadAddress(i), segSize(i)) )
+ needsToSlide = true;
+ }
+ if ( needsToSlide ) {
+ // find a chunk of address space to hold all segments
+ uintptr_t addr = reserveAnAddressRange(highAddr-lowAddr, context);
+ slide = addr - lowAddr;
+ }
+ }
+ else if ( ! this->segmentsCanSlide() ) {
+ for(unsigned int i=0, e=segmentCount(); i < e; ++i) {
+ if ( (strcmp(segName(i), "__PAGEZERO") == 0) && (segFileSize(i) == 0) && (segPreferredLoadAddress(i) == 0) )
+ continue;
+ if ( !reserveAddressRange(segPreferredLoadAddress(i), segSize(i)) )
+ dyld::throwf("can't map unslidable segment %s to 0x%lX with size 0x%lX", segName(i), segPreferredLoadAddress(i), segSize(i));
+ }
+ }
+ else {
+ throw "mach-o does not support independently sliding segments";
+ }
+ return slide;
+}
+
+
+uintptr_t ImageLoaderMachO::reserveAnAddressRange(size_t length, const ImageLoader::LinkContext& context)
+{
+ vm_address_t addr = 0;
+ vm_size_t size = length;
+ // in PIE programs, load initial dylibs after main executable so they don't have fixed addresses either
+ if ( fgNextPIEDylibAddress != 0 ) {
+ // add small (0-3 pages) random padding between dylibs
+ addr = fgNextPIEDylibAddress + (__stack_chk_guard/fgNextPIEDylibAddress & (sizeof(long)-1))*dyld_page_size;
+ //dyld::log("padding 0x%08llX, guard=0x%08llX\n", (long long)(addr - fgNextPIEDylibAddress), (long long)(__stack_chk_guard));
+ kern_return_t r = vm_alloc(&addr, size, VM_FLAGS_FIXED | VM_MAKE_TAG(VM_MEMORY_DYLIB));
+ if ( r == KERN_SUCCESS ) {
+ fgNextPIEDylibAddress = addr + size;
+ return addr;
+ }
+ fgNextPIEDylibAddress = 0;
+ }
+ kern_return_t r = vm_alloc(&addr, size, VM_FLAGS_ANYWHERE | VM_MAKE_TAG(VM_MEMORY_DYLIB));
+ if ( r != KERN_SUCCESS )
+ throw "out of address space";
+
+ return addr;
+}
+
+bool ImageLoaderMachO::reserveAddressRange(uintptr_t start, size_t length)
+{
+ vm_address_t addr = start;
+ vm_size_t size = length;
+ kern_return_t r = vm_alloc(&addr, size, VM_FLAGS_FIXED | VM_MAKE_TAG(VM_MEMORY_DYLIB));
+ if ( r != KERN_SUCCESS )
+ return false;
+ return true;
+}
+
+
+
+void ImageLoaderMachO::mapSegments(int fd, uint64_t offsetInFat, uint64_t lenInFat, uint64_t fileLen, const LinkContext& context)
+{
+ // find address range for image
+ intptr_t slide = this->assignSegmentAddresses(context);
+ if ( context.verboseMapping ) {
+ if ( offsetInFat != 0 )
+ dyld::log("dyld: Mapping %s (slice offset=%llu)\n", this->getPath(), (unsigned long long)offsetInFat);
+ else
+ dyld::log("dyld: Mapping %s\n", this->getPath());
+ }
+ // map in all segments
+ for(unsigned int i=0, e=segmentCount(); i < e; ++i) {
+ vm_offset_t fileOffset = (vm_offset_t)(segFileOffset(i) + offsetInFat);
+ vm_size_t size = segFileSize(i);
+ uintptr_t requestedLoadAddress = segPreferredLoadAddress(i) + slide;
+ int protection = 0;
+ if ( !segUnaccessible(i) ) {
+ if ( segExecutable(i) )
+ protection |= PROT_EXEC;
+ if ( segReadable(i) )
+ protection |= PROT_READ;
+ if ( segWriteable(i) ) {
+ protection |= PROT_WRITE;
+ // rdar://problem/22525618 force __LINKEDIT to always be mapped read-only
+ if ( strcmp(segName(i), "__LINKEDIT") == 0 )
+ protection = PROT_READ;
+ }
+ }
+ #if __i386__
+ // initially map __IMPORT segments R/W so dyld can update them
+ if ( segIsReadOnlyImport(i) )
+ protection |= PROT_WRITE;
+ #endif
+ // wholly zero-fill segments have nothing to mmap() in
+ if ( size > 0 ) {
+ if ( (fileOffset+size) > fileLen ) {
+ dyld::throwf("truncated mach-o error: segment %s extends to %llu which is past end of file %llu",
+ segName(i), (uint64_t)(fileOffset+size), fileLen);
+ }
+ void* loadAddress = xmmap((void*)requestedLoadAddress, size, protection, MAP_FIXED | MAP_PRIVATE, fd, fileOffset);
+ if ( loadAddress == ((void*)(-1)) ) {
+ int mmapErr = errno;
+ if ( mmapErr == EPERM ) {
+ if ( dyld::sandboxBlockedMmap(getPath()) )
+ dyld::throwf("file system sandbox blocked mmap() of '%s'", this->getPath());
+ else
+ dyld::throwf("code signing blocked mmap() of '%s'", this->getPath());
+ }
+ else
+ dyld::throwf("mmap() errno=%d at address=0x%08lX, size=0x%08lX segment=%s in Segment::map() mapping %s",
+ mmapErr, requestedLoadAddress, (uintptr_t)size, segName(i), getPath());
+ }
+ }
+ // update stats
+ ++ImageLoader::fgTotalSegmentsMapped;
+ ImageLoader::fgTotalBytesMapped += size;
+ if ( context.verboseMapping )
+ dyld::log("%18s at 0x%08lX->0x%08lX with permissions %c%c%c\n", segName(i), requestedLoadAddress, requestedLoadAddress+size-1,
+ (protection & PROT_READ) ? 'r' : '.', (protection & PROT_WRITE) ? 'w' : '.', (protection & PROT_EXEC) ? 'x' : '.' );
+ }
+
+ // update slide to reflect load location
+ this->setSlide(slide);
+}
+
+void ImageLoaderMachO::mapSegments(const void* memoryImage, uint64_t imageLen, const LinkContext& context)
+{
+ // find address range for image
+ intptr_t slide = this->assignSegmentAddresses(context);
+ if ( context.verboseMapping )
+ dyld::log("dyld: Mapping memory %p\n", memoryImage);
+ // map in all segments
+ for(unsigned int i=0, e=segmentCount(); i < e; ++i) {
+ vm_address_t loadAddress = segPreferredLoadAddress(i) + slide;
+ vm_address_t srcAddr = (uintptr_t)memoryImage + segFileOffset(i);
+ vm_size_t size = segFileSize(i);
+ kern_return_t r = vm_copy(mach_task_self(), srcAddr, size, loadAddress);
+ if ( r != KERN_SUCCESS )
+ throw "can't map segment";
+ if ( context.verboseMapping )
+ dyld::log("%18s at 0x%08lX->0x%08lX\n", segName(i), (uintptr_t)loadAddress, (uintptr_t)loadAddress+size-1);
+ }
+ // update slide to reflect load location
+ this->setSlide(slide);
+ // set R/W permissions on all segments at slide location
+ for(unsigned int i=0, e=segmentCount(); i < e; ++i) {
+ segProtect(i, context);
+ }
+}
+
+
+void ImageLoaderMachO::segProtect(unsigned int segIndex, const ImageLoader::LinkContext& context)
+{
+ vm_prot_t protection = 0;
+ if ( !segUnaccessible(segIndex) ) {
+ if ( segExecutable(segIndex) )
+ protection |= PROT_EXEC;
+ if ( segReadable(segIndex) )
+ protection |= PROT_READ;
+ if ( segWriteable(segIndex) )
+ protection |= PROT_WRITE;
+ }
+ vm_address_t addr = segActualLoadAddress(segIndex);
+ vm_size_t size = segSize(segIndex);
+ const bool setCurrentPermissions = false;
+ kern_return_t r = vm_protect(mach_task_self(), addr, size, setCurrentPermissions, protection);
+ if ( r != KERN_SUCCESS ) {
+ dyld::throwf("vm_protect(0x%08llX, 0x%08llX, false, 0x%02X) failed, result=%d for segment %s in %s",
+ (long long)addr, (long long)size, protection, r, segName(segIndex), this->getPath());
+ }
+ if ( context.verboseMapping ) {
+ dyld::log("%18s at 0x%08lX->0x%08lX altered permissions to %c%c%c\n", segName(segIndex), (uintptr_t)addr, (uintptr_t)addr+size-1,
+ (protection & PROT_READ) ? 'r' : '.', (protection & PROT_WRITE) ? 'w' : '.', (protection & PROT_EXEC) ? 'x' : '.' );
+ }
+}
+
+#if TEXT_RELOC_SUPPORT
+void ImageLoaderMachO::segMakeWritable(unsigned int segIndex, const ImageLoader::LinkContext& context)
+{
+ vm_address_t addr = segActualLoadAddress(segIndex);
+ vm_size_t size = segSize(segIndex);
+ const bool setCurrentPermissions = false;
+ vm_prot_t protection = VM_PROT_WRITE | VM_PROT_READ | VM_PROT_COPY;
+ if ( segExecutable(segIndex) && !segHasRebaseFixUps(segIndex) )
+ protection |= VM_PROT_EXECUTE;
+ kern_return_t r = vm_protect(mach_task_self(), addr, size, setCurrentPermissions, protection);
+ if ( r != KERN_SUCCESS ) {
+ dyld::throwf("vm_protect(0x%08llX, 0x%08llX, false, 0x%02X) failed, result=%d for segment %s in %s",
+ (long long)addr, (long long)size, protection, r, segName(segIndex), this->getPath());
+ }
+ if ( context.verboseMapping ) {
+ dyld::log("%18s at 0x%08lX->0x%08lX altered permissions to %c%c%c\n", segName(segIndex), (uintptr_t)addr, (uintptr_t)addr+size-1,
+ (protection & PROT_READ) ? 'r' : '.', (protection & PROT_WRITE) ? 'w' : '.', (protection & PROT_EXEC) ? 'x' : '.' );
+ }
+}
+#endif
+
+const char* ImageLoaderMachO::findClosestSymbol(const mach_header* mh, const void* addr, const void** closestAddr)
+{
+ // called by dladdr()
+ // only works with compressed LINKEDIT if classic symbol table is also present
+ const dysymtab_command* dynSymbolTable = NULL;
+ const symtab_command* symtab = NULL;
+ const macho_segment_command* seg;
+ const uint8_t* unslidLinkEditBase = NULL;
+ bool linkEditBaseFound = false;
+ intptr_t slide = 0;
+ const uint32_t cmd_count = mh->ncmds;
+ const load_command* const cmds = (load_command*)((char*)mh + sizeof(macho_header));
+ const load_command* cmd = cmds;
+ for (uint32_t i = 0; i < cmd_count; ++i) {
+ switch (cmd->cmd) {
+ case LC_SEGMENT_COMMAND:
+ seg = (macho_segment_command*)cmd;
+ if ( strcmp(seg->segname, "__LINKEDIT") == 0 ) {
+ unslidLinkEditBase = (uint8_t*)(seg->vmaddr - seg->fileoff);
+ linkEditBaseFound = true;
+ }
+ else if ( strcmp(seg->segname, "__TEXT") == 0 ) {
+ slide = (uintptr_t)mh - seg->vmaddr;
+ }
+ break;
+ case LC_SYMTAB:
+ symtab = (symtab_command*)cmd;
+ break;
+ case LC_DYSYMTAB:
+ dynSymbolTable = (dysymtab_command*)cmd;
+ break;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ // no symbol table => no lookup by address
+ if ( (symtab == NULL) || (dynSymbolTable == NULL) || !linkEditBaseFound )
+ return NULL;
+
+ const uint8_t* linkEditBase = unslidLinkEditBase + slide;
+ const char* symbolTableStrings = (const char*)&linkEditBase[symtab->stroff];
+ const macho_nlist* symbolTable = (macho_nlist*)(&linkEditBase[symtab->symoff]);
+
+ uintptr_t targetAddress = (uintptr_t)addr - slide;
+ const struct macho_nlist* bestSymbol = NULL;
+ // first walk all global symbols
+ const struct macho_nlist* const globalsStart = &symbolTable[dynSymbolTable->iextdefsym];
+ const struct macho_nlist* const globalsEnd= &globalsStart[dynSymbolTable->nextdefsym];
+ for (const struct macho_nlist* s = globalsStart; s < globalsEnd; ++s) {
+ if ( (s->n_type & N_TYPE) == N_SECT ) {
+ if ( bestSymbol == NULL ) {
+ if ( s->n_value <= targetAddress )
+ bestSymbol = s;
+ }
+ else if ( (s->n_value <= targetAddress) && (bestSymbol->n_value < s->n_value) ) {
+ bestSymbol = s;
+ }
+ }
+ }
+ // next walk all local symbols
+ const struct macho_nlist* const localsStart = &symbolTable[dynSymbolTable->ilocalsym];
+ const struct macho_nlist* const localsEnd= &localsStart[dynSymbolTable->nlocalsym];
+ for (const struct macho_nlist* s = localsStart; s < localsEnd; ++s) {
+ if ( ((s->n_type & N_TYPE) == N_SECT) && ((s->n_type & N_STAB) == 0) ) {
+ if ( bestSymbol == NULL ) {
+ if ( s->n_value <= targetAddress )
+ bestSymbol = s;
+ }
+ else if ( (s->n_value <= targetAddress) && (bestSymbol->n_value < s->n_value) ) {
+ bestSymbol = s;
+ }
+ }
+ }
+ if ( bestSymbol != NULL ) {
+#if __arm__
+ if (bestSymbol->n_desc & N_ARM_THUMB_DEF)
+ *closestAddr = (void*)((bestSymbol->n_value | 1) + slide);
+ else
+ *closestAddr = (void*)(bestSymbol->n_value + slide);
+#else
+ *closestAddr = (void*)(bestSymbol->n_value + slide);
+#endif
+ return &symbolTableStrings[bestSymbol->n_un.n_strx];
+ }
+ return NULL;
+}
+
+bool ImageLoaderMachO::getLazyBindingInfo(uint32_t& lazyBindingInfoOffset, const uint8_t* lazyInfoStart, const uint8_t* lazyInfoEnd,
+ uint8_t* segIndex, uintptr_t* segOffset, int* ordinal, const char** symbolName, bool* doneAfterBind)
+{
+ if ( lazyBindingInfoOffset > (lazyInfoEnd-lazyInfoStart) )
+ return false;
+ uint8_t type = BIND_TYPE_POINTER;
+ uint8_t symboFlags = 0;
+ bool done = false;
+ const uint8_t* p = &lazyInfoStart[lazyBindingInfoOffset];
+ while ( !done && (p < lazyInfoEnd) ) {
+ uint8_t immediate = *p & BIND_IMMEDIATE_MASK;
+ uint8_t opcode = *p & BIND_OPCODE_MASK;
+ ++p;
+ switch (opcode) {
+ case BIND_OPCODE_DONE:
+ *doneAfterBind = false;
+ return true;
+ break;
+ case BIND_OPCODE_SET_DYLIB_ORDINAL_IMM:
+ *ordinal = immediate;
+ break;
+ case BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB:
+ *ordinal = (int)read_uleb128(p, lazyInfoEnd);
+ break;
+ case BIND_OPCODE_SET_DYLIB_SPECIAL_IMM:
+ // the special ordinals are negative numbers
+ if ( immediate == 0 )
+ *ordinal = 0;
+ else {
+ int8_t signExtended = BIND_OPCODE_MASK | immediate;
+ *ordinal = signExtended;
+ }
+ break;
+ case BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
+ *symbolName = (char*)p;
+ symboFlags = immediate;
+ while (*p != '\0')
+ ++p;
+ ++p;
+ break;
+ case BIND_OPCODE_SET_TYPE_IMM:
+ type = immediate;
+ break;
+ case BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
+ *segIndex = immediate;
+ *segOffset = read_uleb128(p, lazyInfoEnd);
+ break;
+ case BIND_OPCODE_DO_BIND:
+ *doneAfterBind = ((*p & BIND_OPCODE_MASK) == BIND_OPCODE_DONE);
+ lazyBindingInfoOffset += p - &lazyInfoStart[lazyBindingInfoOffset];
+ return true;
+ break;
+ case BIND_OPCODE_SET_ADDEND_SLEB:
+ case BIND_OPCODE_ADD_ADDR_ULEB:
+ case BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB:
+ case BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED:
+ case BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB:
+ default:
+ return false;
+ }
+ }
+ return false;
+}
+
+const dyld_info_command* ImageLoaderMachO::findDyldInfoLoadCommand(const mach_header* mh)
+{
+ const uint32_t cmd_count = mh->ncmds;
+ const load_command* const cmds = (load_command*)((char*)mh + sizeof(macho_header));
+ const load_command* cmd = cmds;
+ for (uint32_t i = 0; i < cmd_count; ++i) {
+ switch (cmd->cmd) {
+ case LC_DYLD_INFO:
+ case LC_DYLD_INFO_ONLY:
+ return (dyld_info_command*)cmd;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ return NULL;
+}
+
+
+uintptr_t ImageLoaderMachO::segPreferredAddress(const mach_header* mh, unsigned segIndex)
+{
+ const uint32_t cmd_count = mh->ncmds;
+ const load_command* const cmds = (load_command*)((char*)mh + sizeof(macho_header));
+ const load_command* cmd = cmds;
+ unsigned curSegIndex = 0;
+ for (uint32_t i = 0; i < cmd_count; ++i) {
+ if ( cmd->cmd == LC_SEGMENT_COMMAND ) {
+ if ( segIndex == curSegIndex ) {
+ const macho_segment_command* segCmd = (macho_segment_command*)cmd;
+ return segCmd->vmaddr;
+ }
+ ++curSegIndex;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ return 0;
+}
+
+
+
+uintptr_t ImageLoaderMachO::imageBaseAddress() const {
+ //printf("imageBaseAddress: %s %d->%d\n", getPath(), 0, segmentCount());
+ for (unsigned int i = 0, e = segmentCount(); i != e; ++i) {
+ if ( (segFileOffset(i) == 0) && (segFileSize(i) != 0) )
+ return segPreferredLoadAddress(i);
+ }
+ return 0;
+}
+