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[apple/dyld.git] / src / ImageLoaderMachOCompressed.cpp
1 /* -*- mode: C++; c-basic-offset: 4; tab-width: 4 -*-
2 *
3 * Copyright (c) 2008 Apple Inc. All rights reserved.
4 *
5 * @APPLE_LICENSE_HEADER_START@
6 *
7 * This file contains Original Code and/or Modifications of Original Code
8 * as defined in and that are subject to the Apple Public Source License
9 * Version 2.0 (the 'License'). You may not use this file except in
10 * compliance with the License. Please obtain a copy of the License at
11 * http://www.opensource.apple.com/apsl/ and read it before using this
12 * file.
13 *
14 * The Original Code and all software distributed under the License are
15 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
16 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
17 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
19 * Please see the License for the specific language governing rights and
20 * limitations under the License.
21 *
22 * @APPLE_LICENSE_HEADER_END@
23 */
24
25
26 #if __arm__ || __arm64__
27 #include <System/sys/mman.h>
28 #else
29 #include <sys/mman.h>
30 #endif
31 #include <string.h>
32 #include <fcntl.h>
33 #include <errno.h>
34 #include <sys/types.h>
35 #include <sys/fcntl.h>
36 #include <sys/stat.h>
37 #include <sys/param.h>
38 #include <mach/mach.h>
39 #include <mach/thread_status.h>
40 #include <mach-o/loader.h>
41 #include <mach-o/dyld_images.h>
42
43 #include "dyld2.h"
44 #include "ImageLoaderMachOCompressed.h"
45 #include "Closure.h"
46 #include "Array.h"
47
48 #ifndef BIND_SUBOPCODE_THREADED_SET_JOP
49 #define BIND_SUBOPCODE_THREADED_SET_JOP 0x0F
50 #endif
51
52 // relocation_info.r_length field has value 3 for 64-bit executables and value 2 for 32-bit executables
53 #if __LP64__
54 #define RELOC_SIZE 3
55 #define LC_SEGMENT_COMMAND LC_SEGMENT_64
56 #define LC_ROUTINES_COMMAND LC_ROUTINES_64
57 struct macho_segment_command : public segment_command_64 {};
58 struct macho_section : public section_64 {};
59 struct macho_routines_command : public routines_command_64 {};
60 #else
61 #define RELOC_SIZE 2
62 #define LC_SEGMENT_COMMAND LC_SEGMENT
63 #define LC_ROUTINES_COMMAND LC_ROUTINES
64 struct macho_segment_command : public segment_command {};
65 struct macho_section : public section {};
66 struct macho_routines_command : public routines_command {};
67 #endif
68
69
70
71 // create image for main executable
72 ImageLoaderMachOCompressed* ImageLoaderMachOCompressed::instantiateMainExecutable(const macho_header* mh, uintptr_t slide, const char* path,
73 unsigned int segCount, unsigned int libCount, const LinkContext& context)
74 {
75 ImageLoaderMachOCompressed* image = ImageLoaderMachOCompressed::instantiateStart(mh, path, segCount, libCount);
76
77 // set slide for PIE programs
78 image->setSlide(slide);
79
80 // for PIE record end of program, to know where to start loading dylibs
81 if ( slide != 0 )
82 fgNextPIEDylibAddress = (uintptr_t)image->getEnd();
83
84 image->disableCoverageCheck();
85 image->instantiateFinish(context);
86 image->setMapped(context);
87
88 if ( context.verboseMapping ) {
89 dyld::log("dyld: Main executable mapped %s\n", path);
90 for(unsigned int i=0, e=image->segmentCount(); i < e; ++i) {
91 const char* name = image->segName(i);
92 if ( (strcmp(name, "__PAGEZERO") == 0) || (strcmp(name, "__UNIXSTACK") == 0) )
93 dyld::log("%18s at 0x%08lX->0x%08lX\n", name, image->segPreferredLoadAddress(i), image->segPreferredLoadAddress(i)+image->segSize(i));
94 else
95 dyld::log("%18s at 0x%08lX->0x%08lX\n", name, image->segActualLoadAddress(i), image->segActualEndAddress(i));
96 }
97 }
98
99 return image;
100 }
101
102 // create image by mapping in a mach-o file
103 ImageLoaderMachOCompressed* ImageLoaderMachOCompressed::instantiateFromFile(const char* path, int fd, const uint8_t* fileData, size_t lenFileData,
104 uint64_t offsetInFat, uint64_t lenInFat, const struct stat& info,
105 unsigned int segCount, unsigned int libCount,
106 const struct linkedit_data_command* codeSigCmd,
107 const struct encryption_info_command* encryptCmd,
108 const LinkContext& context)
109 {
110 ImageLoaderMachOCompressed* image = ImageLoaderMachOCompressed::instantiateStart((macho_header*)fileData, path, segCount, libCount);
111
112 try {
113 // record info about file
114 image->setFileInfo(info.st_dev, info.st_ino, info.st_mtime);
115
116 // if this image is code signed, let kernel validate signature before mapping any pages from image
117 image->loadCodeSignature(codeSigCmd, fd, offsetInFat, context);
118
119 // Validate that first data we read with pread actually matches with code signature
120 image->validateFirstPages(codeSigCmd, fd, fileData, lenFileData, offsetInFat, context);
121
122 // mmap segments
123 image->mapSegments(fd, offsetInFat, lenInFat, info.st_size, context);
124
125 // if framework is FairPlay encrypted, register with kernel
126 image->registerEncryption(encryptCmd, context);
127
128 // probe to see if code signed correctly
129 image->crashIfInvalidCodeSignature();
130
131 // finish construction
132 image->instantiateFinish(context);
133
134 // if path happens to be same as in LC_DYLIB_ID load command use that, otherwise malloc a copy of the path
135 const char* installName = image->getInstallPath();
136 if ( (installName != NULL) && (strcmp(installName, path) == 0) && (path[0] == '/') )
137 image->setPathUnowned(installName);
138 #if __MAC_OS_X_VERSION_MIN_REQUIRED
139 // <rdar://problem/6563887> app crashes when libSystem cannot be found
140 else if ( (installName != NULL) && (strcmp(path, "/usr/lib/libgcc_s.1.dylib") == 0) && (strcmp(installName, "/usr/lib/libSystem.B.dylib") == 0) )
141 image->setPathUnowned("/usr/lib/libSystem.B.dylib");
142 #endif
143 else if ( (path[0] != '/') || (strstr(path, "../") != NULL) ) {
144 // rdar://problem/10733082 Fix up @rpath based paths during introspection
145 // rdar://problem/5135363 turn relative paths into absolute paths so gdb, Symbolication can later find them
146 char realPath[MAXPATHLEN];
147 if ( fcntl(fd, F_GETPATH, realPath) == 0 )
148 image->setPaths(path, realPath);
149 else
150 image->setPath(path);
151 }
152 else {
153 // <rdar://problem/46682306> always try to realpath dylibs since they may have been dlopen()ed using a symlink path
154 if ( installName != NULL ) {
155 char realPath[MAXPATHLEN];
156 if ( (fcntl(fd, F_GETPATH, realPath) == 0) && (strcmp(path, realPath) != 0) )
157 image->setPaths(path, realPath);
158 else
159 image->setPath(path);
160 }
161 else {
162 image->setPath(path);
163 }
164 }
165
166 // make sure path is stable before recording in dyld_all_image_infos
167 image->setMapped(context);
168
169 }
170 catch (...) {
171 // ImageLoader::setMapped() can throw an exception to block loading of image
172 // <rdar://problem/6169686> Leaked fSegmentsArray and image segments during failed dlopen_preflight
173 delete image;
174 throw;
175 }
176
177 return image;
178 }
179
180 // create image by using cached mach-o file
181 ImageLoaderMachOCompressed* ImageLoaderMachOCompressed::instantiateFromCache(const macho_header* mh, const char* path, long slide,
182 const struct stat& info, unsigned int segCount,
183 unsigned int libCount, const LinkContext& context)
184 {
185 ImageLoaderMachOCompressed* image = ImageLoaderMachOCompressed::instantiateStart(mh, path, segCount, libCount);
186 try {
187 // record info about file
188 image->setFileInfo(info.st_dev, info.st_ino, info.st_mtime);
189
190 // remember this is from shared cache and cannot be unloaded
191 image->fInSharedCache = true;
192 image->setNeverUnload();
193 image->setSlide(slide);
194 image->disableCoverageCheck();
195
196 // segments already mapped in cache
197 if ( context.verboseMapping ) {
198 dyld::log("dyld: Using shared cached for %s\n", path);
199 for(unsigned int i=0; i < image->fSegmentsCount; ++i) {
200 dyld::log("%18s at 0x%08lX->0x%08lX\n", image->segName(i), image->segActualLoadAddress(i), image->segActualEndAddress(i));
201 }
202 }
203
204 image->instantiateFinish(context);
205
206 #if TARGET_OS_SIMULATOR
207 char realPath[MAXPATHLEN] = { 0 };
208 if ( dyld::gLinkContext.rootPaths == NULL )
209 throw "root path is not set";
210 strlcpy(realPath, dyld::gLinkContext.rootPaths[0], MAXPATHLEN);
211 strlcat(realPath, path, MAXPATHLEN);
212 image->setPaths(path, realPath);
213 #endif
214 image->setMapped(context);
215 }
216 catch (...) {
217 // ImageLoader::setMapped() can throw an exception to block loading of image
218 // <rdar://problem/6169686> Leaked fSegmentsArray and image segments during failed dlopen_preflight
219 delete image;
220 throw;
221 }
222
223 return image;
224 }
225
226 // create image by copying an in-memory mach-o file
227 ImageLoaderMachOCompressed* ImageLoaderMachOCompressed::instantiateFromMemory(const char* moduleName, const macho_header* mh, uint64_t len,
228 unsigned int segCount, unsigned int libCount, const LinkContext& context)
229 {
230 ImageLoaderMachOCompressed* image = ImageLoaderMachOCompressed::instantiateStart(mh, moduleName, segCount, libCount);
231 try {
232 // map segments
233 if ( mh->filetype == MH_EXECUTE )
234 throw "can't load another MH_EXECUTE";
235
236 // vmcopy segments
237 image->mapSegments((const void*)mh, len, context);
238
239 // for compatibility, never unload dylibs loaded from memory
240 image->setNeverUnload();
241
242 image->disableCoverageCheck();
243
244 // bundle loads need path copied
245 if ( moduleName != NULL )
246 image->setPath(moduleName);
247
248 image->instantiateFinish(context);
249 image->setMapped(context);
250 }
251 catch (...) {
252 // ImageLoader::setMapped() can throw an exception to block loading of image
253 // <rdar://problem/6169686> Leaked fSegmentsArray and image segments during failed dlopen_preflight
254 delete image;
255 throw;
256 }
257
258 return image;
259 }
260
261
262 ImageLoaderMachOCompressed::ImageLoaderMachOCompressed(const macho_header* mh, const char* path, unsigned int segCount,
263 uint32_t segOffsets[], unsigned int libCount)
264 : ImageLoaderMachO(mh, path, segCount, segOffsets, libCount), fDyldInfo(NULL), fChainedFixups(NULL), fExportsTrie(NULL)
265 {
266 }
267
268 ImageLoaderMachOCompressed::~ImageLoaderMachOCompressed()
269 {
270 // don't do clean up in ~ImageLoaderMachO() because virtual call to segmentCommandOffsets() won't work
271 destroy();
272 }
273
274
275
276 // construct ImageLoaderMachOCompressed using "placement new" with SegmentMachO objects array at end
277 ImageLoaderMachOCompressed* ImageLoaderMachOCompressed::instantiateStart(const macho_header* mh, const char* path,
278 unsigned int segCount, unsigned int libCount)
279 {
280 size_t size = sizeof(ImageLoaderMachOCompressed) + segCount * sizeof(uint32_t) + libCount * sizeof(ImageLoader*);
281 ImageLoaderMachOCompressed* allocatedSpace = static_cast<ImageLoaderMachOCompressed*>(malloc(size));
282 if ( allocatedSpace == NULL )
283 throw "malloc failed";
284 uint32_t* segOffsets = ((uint32_t*)(((uint8_t*)allocatedSpace) + sizeof(ImageLoaderMachOCompressed)));
285 bzero(&segOffsets[segCount], libCount*sizeof(void*)); // zero out lib array
286 return new (allocatedSpace) ImageLoaderMachOCompressed(mh, path, segCount, segOffsets, libCount);
287 }
288
289
290 // common code to finish initializing object
291 void ImageLoaderMachOCompressed::instantiateFinish(const LinkContext& context)
292 {
293 // now that segments are mapped in, get real fMachOData, fLinkEditBase, and fSlide
294 this->parseLoadCmds(context);
295 }
296
297 uint32_t* ImageLoaderMachOCompressed::segmentCommandOffsets() const
298 {
299 return ((uint32_t*)(((uint8_t*)this) + sizeof(ImageLoaderMachOCompressed)));
300 }
301
302
303 ImageLoader* ImageLoaderMachOCompressed::libImage(unsigned int libIndex) const
304 {
305 const uintptr_t* images = ((uintptr_t*)(((uint8_t*)this) + sizeof(ImageLoaderMachOCompressed) + fSegmentsCount*sizeof(uint32_t)));
306 // mask off low bits
307 return (ImageLoader*)(images[libIndex] & (-4));
308 }
309
310 bool ImageLoaderMachOCompressed::libReExported(unsigned int libIndex) const
311 {
312 const uintptr_t* images = ((uintptr_t*)(((uint8_t*)this) + sizeof(ImageLoaderMachOCompressed) + fSegmentsCount*sizeof(uint32_t)));
313 // re-export flag is low bit
314 return ((images[libIndex] & 1) != 0);
315 }
316
317 bool ImageLoaderMachOCompressed::libIsUpward(unsigned int libIndex) const
318 {
319 const uintptr_t* images = ((uintptr_t*)(((uint8_t*)this) + sizeof(ImageLoaderMachOCompressed) + fSegmentsCount*sizeof(uint32_t)));
320 // re-export flag is second bit
321 return ((images[libIndex] & 2) != 0);
322 }
323
324
325 void ImageLoaderMachOCompressed::setLibImage(unsigned int libIndex, ImageLoader* image, bool reExported, bool upward)
326 {
327 uintptr_t* images = ((uintptr_t*)(((uint8_t*)this) + sizeof(ImageLoaderMachOCompressed) + fSegmentsCount*sizeof(uint32_t)));
328 uintptr_t value = (uintptr_t)image;
329 if ( reExported )
330 value |= 1;
331 if ( upward )
332 value |= 2;
333 images[libIndex] = value;
334 }
335
336
337 void ImageLoaderMachOCompressed::rebaseAt(const LinkContext& context, uintptr_t addr, uintptr_t slide, uint8_t type)
338 {
339 if ( context.verboseRebase ) {
340 dyld::log("dyld: rebase: %s:*0x%08lX += 0x%08lX\n", this->getShortName(), (uintptr_t)addr, slide);
341 }
342 //dyld::log("0x%08lX type=%d\n", addr, type);
343 uintptr_t* locationToFix = (uintptr_t*)addr;
344 switch (type) {
345 case REBASE_TYPE_POINTER:
346 *locationToFix += slide;
347 break;
348 case REBASE_TYPE_TEXT_ABSOLUTE32:
349 *locationToFix += slide;
350 break;
351 default:
352 dyld::throwf("bad rebase type %d", type);
353 }
354 }
355
356 void ImageLoaderMachOCompressed::throwBadRebaseAddress(uintptr_t address, uintptr_t segmentEndAddress, int segmentIndex,
357 const uint8_t* startOpcodes, const uint8_t* endOpcodes, const uint8_t* pos)
358 {
359 dyld::throwf("malformed rebase opcodes (%ld/%ld): address 0x%08lX is outside of segment %s (0x%08lX -> 0x%08lX)",
360 (intptr_t)(pos-startOpcodes), (intptr_t)(endOpcodes-startOpcodes), address, segName(segmentIndex),
361 segActualLoadAddress(segmentIndex), segmentEndAddress);
362 }
363
364 void ImageLoaderMachOCompressed::rebase(const LinkContext& context, uintptr_t slide)
365 {
366 // binary uses chained fixups where are applied during binding
367 if ( fDyldInfo == NULL )
368 return;
369
370 CRSetCrashLogMessage2(this->getPath());
371 const uint8_t* const start = fLinkEditBase + fDyldInfo->rebase_off;
372 const uint8_t* const end = &start[fDyldInfo->rebase_size];
373 const uint8_t* p = start;
374
375 if ( start == end )
376 return;
377
378 uint32_t ignore;
379 bool bindingBecauseOfRoot = this->overridesCachedDylib(ignore);
380 vmAccountingSetSuspended(context, bindingBecauseOfRoot);
381
382 try {
383 uint8_t type = 0;
384 int segmentIndex = 0;
385 uintptr_t address = segActualLoadAddress(0);
386 uintptr_t segmentStartAddress = segActualLoadAddress(0);
387 uintptr_t segmentEndAddress = segActualEndAddress(0);
388 uintptr_t count;
389 uintptr_t skip;
390 bool done = false;
391 while ( !done && (p < end) ) {
392 uint8_t immediate = *p & REBASE_IMMEDIATE_MASK;
393 uint8_t opcode = *p & REBASE_OPCODE_MASK;
394 ++p;
395 switch (opcode) {
396 case REBASE_OPCODE_DONE:
397 done = true;
398 break;
399 case REBASE_OPCODE_SET_TYPE_IMM:
400 type = immediate;
401 break;
402 case REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
403 segmentIndex = immediate;
404 if ( segmentIndex >= fSegmentsCount )
405 dyld::throwf("REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is too large (0..%d)",
406 segmentIndex, fSegmentsCount-1);
407 #if TEXT_RELOC_SUPPORT
408 if ( !segWriteable(segmentIndex) && !segHasRebaseFixUps(segmentIndex) && !segHasBindFixUps(segmentIndex) )
409 #else
410 if ( !segWriteable(segmentIndex) )
411 #endif
412 dyld::throwf("REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is not a writable segment (%s)",
413 segmentIndex, segName(segmentIndex));
414 segmentStartAddress = segActualLoadAddress(segmentIndex);
415 segmentEndAddress = segActualEndAddress(segmentIndex);
416 address = segmentStartAddress + read_uleb128(p, end);
417 break;
418 case REBASE_OPCODE_ADD_ADDR_ULEB:
419 address += read_uleb128(p, end);
420 break;
421 case REBASE_OPCODE_ADD_ADDR_IMM_SCALED:
422 address += immediate*sizeof(uintptr_t);
423 break;
424 case REBASE_OPCODE_DO_REBASE_IMM_TIMES:
425 for (int i=0; i < immediate; ++i) {
426 if ( (address < segmentStartAddress) || (address >= segmentEndAddress) )
427 throwBadRebaseAddress(address, segmentEndAddress, segmentIndex, start, end, p);
428 rebaseAt(context, address, slide, type);
429 address += sizeof(uintptr_t);
430 }
431 fgTotalRebaseFixups += immediate;
432 break;
433 case REBASE_OPCODE_DO_REBASE_ULEB_TIMES:
434 count = read_uleb128(p, end);
435 for (uint32_t i=0; i < count; ++i) {
436 if ( (address < segmentStartAddress) || (address >= segmentEndAddress) )
437 throwBadRebaseAddress(address, segmentEndAddress, segmentIndex, start, end, p);
438 rebaseAt(context, address, slide, type);
439 address += sizeof(uintptr_t);
440 }
441 fgTotalRebaseFixups += count;
442 break;
443 case REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB:
444 if ( (address < segmentStartAddress) || (address >= segmentEndAddress) )
445 throwBadRebaseAddress(address, segmentEndAddress, segmentIndex, start, end, p);
446 rebaseAt(context, address, slide, type);
447 address += read_uleb128(p, end) + sizeof(uintptr_t);
448 ++fgTotalRebaseFixups;
449 break;
450 case REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_ULEB:
451 count = read_uleb128(p, end);
452 skip = read_uleb128(p, end);
453 for (uint32_t i=0; i < count; ++i) {
454 if ( (address < segmentStartAddress) || (address >= segmentEndAddress) )
455 throwBadRebaseAddress(address, segmentEndAddress, segmentIndex, start, end, p);
456 rebaseAt(context, address, slide, type);
457 address += skip + sizeof(uintptr_t);
458 }
459 fgTotalRebaseFixups += count;
460 break;
461 default:
462 dyld::throwf("bad rebase opcode %d", *(p-1));
463 }
464 }
465 }
466 catch (const char* msg) {
467 const char* newMsg = dyld::mkstringf("%s in %s", msg, this->getPath());
468 free((void*)msg);
469 throw newMsg;
470 }
471 CRSetCrashLogMessage2(NULL);
472 }
473
474 const ImageLoader::Symbol* ImageLoaderMachOCompressed::findShallowExportedSymbol(const char* symbol, const ImageLoader** foundIn) const
475 {
476 //dyld::log("Compressed::findExportedSymbol(%s) in %s\n", symbol, this->getShortName());
477 uint32_t trieFileOffset = fDyldInfo ? fDyldInfo->export_off : fExportsTrie->dataoff;
478 uint32_t trieFileSize = fDyldInfo ? fDyldInfo->export_size : fExportsTrie->datasize;
479 if ( trieFileSize == 0 )
480 return NULL;
481 #if LOG_BINDINGS
482 dyld::logBindings("%s: %s\n", this->getShortName(), symbol);
483 #endif
484 ++ImageLoaderMachO::fgSymbolTrieSearchs;
485 const uint8_t* start = &fLinkEditBase[trieFileOffset];
486 const uint8_t* end = &start[trieFileSize];
487 const uint8_t* foundNodeStart = this->trieWalk(start, end, symbol);
488 if ( foundNodeStart != NULL ) {
489 const uint8_t* p = foundNodeStart;
490 const uintptr_t flags = read_uleb128(p, end);
491 // found match, return pointer to terminal part of node
492 if ( flags & EXPORT_SYMBOL_FLAGS_REEXPORT ) {
493 // re-export from another dylib, lookup there
494 const uintptr_t ordinal = read_uleb128(p, end);
495 const char* importedName = (char*)p;
496 if ( importedName[0] == '\0' )
497 importedName = symbol;
498 if ( (ordinal > 0) && (ordinal <= libraryCount()) ) {
499 const ImageLoader* reexportedFrom = libImage((unsigned int)ordinal-1);
500 // Missing weak-dylib
501 if ( reexportedFrom == NULL )
502 return NULL;
503 //dyld::log("Compressed::findExportedSymbol(), %s -> %s/%s\n", symbol, reexportedFrom->getShortName(), importedName);
504 const char* reExportLibPath = libPath((unsigned int)ordinal-1);
505 return reexportedFrom->findExportedSymbol(importedName, true, reExportLibPath, foundIn);
506 }
507 else {
508 //dyld::throwf("bad mach-o binary, library ordinal (%u) invalid (max %u) for re-exported symbol %s in %s",
509 // ordinal, libraryCount(), symbol, this->getPath());
510 }
511 }
512 else {
513 //dyld::log("findExportedSymbol(%s) in %s found match, returning %p\n", symbol, this->getShortName(), p);
514 if ( foundIn != NULL )
515 *foundIn = (ImageLoader*)this;
516 // return pointer to terminal part of node
517 return (Symbol*)foundNodeStart;
518 }
519 }
520 return NULL;
521 }
522
523
524 bool ImageLoaderMachOCompressed::containsSymbol(const void* addr) const
525 {
526 uint32_t trieFileOffset = fDyldInfo ? fDyldInfo->export_off : fExportsTrie->dataoff;
527 uint32_t trieFileSize = fDyldInfo ? fDyldInfo->export_size : fExportsTrie->datasize;
528 const uint8_t* start = &fLinkEditBase[trieFileOffset];
529 const uint8_t* end = &start[trieFileSize];
530 return ( (start <= addr) && (addr < end) );
531 }
532
533
534 uintptr_t ImageLoaderMachOCompressed::exportedSymbolAddress(const LinkContext& context, const Symbol* symbol, const ImageLoader* requestor, bool runResolver) const
535 {
536 uint32_t trieFileOffset = fDyldInfo ? fDyldInfo->export_off : fExportsTrie->dataoff;
537 uint32_t trieFileSize = fDyldInfo ? fDyldInfo->export_size : fExportsTrie->datasize;
538 const uint8_t* exportNode = (uint8_t*)symbol;
539 const uint8_t* exportTrieStart = fLinkEditBase + trieFileOffset;
540 const uint8_t* exportTrieEnd = exportTrieStart + trieFileSize;
541 if ( (exportNode < exportTrieStart) || (exportNode > exportTrieEnd) )
542 throw "symbol is not in trie";
543 //dyld::log("exportedSymbolAddress(): node=%p, nodeOffset=0x%04X in %s\n", symbol, (int)((uint8_t*)symbol - exportTrieStart), this->getShortName());
544 uintptr_t flags = read_uleb128(exportNode, exportTrieEnd);
545 switch ( flags & EXPORT_SYMBOL_FLAGS_KIND_MASK ) {
546 case EXPORT_SYMBOL_FLAGS_KIND_REGULAR:
547 if ( runResolver && (flags & EXPORT_SYMBOL_FLAGS_STUB_AND_RESOLVER) ) {
548 // this node has a stub and resolver, run the resolver to get target address
549 uintptr_t stub = read_uleb128(exportNode, exportTrieEnd) + (uintptr_t)fMachOData; // skip over stub
550 // <rdar://problem/10657737> interposing dylibs have the stub address as their replacee
551 uintptr_t interposedStub = interposedAddress(context, stub, requestor);
552 if ( interposedStub != stub )
553 return interposedStub;
554 // stub was not interposed, so run resolver
555 typedef uintptr_t (*ResolverProc)(void);
556 ResolverProc resolver = (ResolverProc)(read_uleb128(exportNode, exportTrieEnd) + (uintptr_t)fMachOData);
557 #if __has_feature(ptrauth_calls)
558 resolver = (ResolverProc)__builtin_ptrauth_sign_unauthenticated(resolver, ptrauth_key_asia, 0);
559 #endif
560 uintptr_t result = (*resolver)();
561 if ( context.verboseBind )
562 dyld::log("dyld: resolver at %p returned 0x%08lX\n", resolver, result);
563 #if __has_feature(ptrauth_calls)
564 result = (uintptr_t)__builtin_ptrauth_strip((void*)result, ptrauth_key_asia);
565 #endif
566 return result;
567 }
568 return read_uleb128(exportNode, exportTrieEnd) + (uintptr_t)fMachOData;
569 case EXPORT_SYMBOL_FLAGS_KIND_THREAD_LOCAL:
570 if ( flags & EXPORT_SYMBOL_FLAGS_STUB_AND_RESOLVER )
571 dyld::throwf("unsupported exported symbol kind. flags=%lu at node=%p", flags, symbol);
572 return read_uleb128(exportNode, exportTrieEnd) + (uintptr_t)fMachOData;
573 case EXPORT_SYMBOL_FLAGS_KIND_ABSOLUTE:
574 if ( flags & EXPORT_SYMBOL_FLAGS_STUB_AND_RESOLVER )
575 dyld::throwf("unsupported exported symbol kind. flags=%lu at node=%p", flags, symbol);
576 return read_uleb128(exportNode, exportTrieEnd);
577 default:
578 dyld::throwf("unsupported exported symbol kind. flags=%lu at node=%p", flags, symbol);
579 }
580 }
581
582 bool ImageLoaderMachOCompressed::exportedSymbolIsWeakDefintion(const Symbol* symbol) const
583 {
584 uint32_t trieFileOffset = fDyldInfo ? fDyldInfo->export_off : fExportsTrie->dataoff;
585 uint32_t trieFileSize = fDyldInfo ? fDyldInfo->export_size : fExportsTrie->datasize;
586 const uint8_t* exportNode = (uint8_t*)symbol;
587 const uint8_t* exportTrieStart = fLinkEditBase + trieFileOffset;
588 const uint8_t* exportTrieEnd = exportTrieStart + trieFileSize;
589 if ( (exportNode < exportTrieStart) || (exportNode > exportTrieEnd) )
590 throw "symbol is not in trie";
591 uintptr_t flags = read_uleb128(exportNode, exportTrieEnd);
592 return ( flags & EXPORT_SYMBOL_FLAGS_WEAK_DEFINITION );
593 }
594
595
596 const char* ImageLoaderMachOCompressed::exportedSymbolName(const Symbol* symbol) const
597 {
598 throw "NSNameOfSymbol() not supported with compressed LINKEDIT";
599 }
600
601 unsigned int ImageLoaderMachOCompressed::exportedSymbolCount() const
602 {
603 throw "NSSymbolDefinitionCountInObjectFileImage() not supported with compressed LINKEDIT";
604 }
605
606 const ImageLoader::Symbol* ImageLoaderMachOCompressed::exportedSymbolIndexed(unsigned int index) const
607 {
608 throw "NSSymbolDefinitionNameInObjectFileImage() not supported with compressed LINKEDIT";
609 }
610
611 unsigned int ImageLoaderMachOCompressed::importedSymbolCount() const
612 {
613 throw "NSSymbolReferenceCountInObjectFileImage() not supported with compressed LINKEDIT";
614 }
615
616 const ImageLoader::Symbol* ImageLoaderMachOCompressed::importedSymbolIndexed(unsigned int index) const
617 {
618 throw "NSSymbolReferenceCountInObjectFileImage() not supported with compressed LINKEDIT";
619 }
620
621 const char* ImageLoaderMachOCompressed::importedSymbolName(const Symbol* symbol) const
622 {
623 throw "NSSymbolReferenceNameInObjectFileImage() not supported with compressed LINKEDIT";
624 }
625
626
627
628 uintptr_t ImageLoaderMachOCompressed::resolveFlat(const LinkContext& context, const char* symbolName, bool weak_import,
629 bool runResolver, const ImageLoader** foundIn)
630 {
631 const Symbol* sym;
632 if ( context.flatExportFinder(symbolName, &sym, foundIn) ) {
633 if ( *foundIn != this )
634 context.addDynamicReference(this, const_cast<ImageLoader*>(*foundIn));
635 return (*foundIn)->getExportedSymbolAddress(sym, context, this, runResolver);
636 }
637 // if a bundle is loaded privately the above will not find its exports
638 if ( this->isBundle() && this->hasHiddenExports() ) {
639 // look in self for needed symbol
640 sym = this->findShallowExportedSymbol(symbolName, foundIn);
641 if ( sym != NULL )
642 return (*foundIn)->getExportedSymbolAddress(sym, context, this, runResolver);
643 }
644 if ( weak_import ) {
645 // definition can't be found anywhere, ok because it is weak, just return 0
646 return 0;
647 }
648 throwSymbolNotFound(context, symbolName, this->getPath(), "", "flat namespace");
649 }
650
651
652 static void patchCacheUsesOf(const ImageLoader::LinkContext& context, const dyld3::closure::Image* overriddenImage,
653 uint32_t cacheOffsetOfImpl, const char* symbolName, uintptr_t newImpl)
654 {
655 uintptr_t cacheStart = (uintptr_t)context.dyldCache;
656 uint32_t imageIndex = overriddenImage->imageNum() - (uint32_t)context.dyldCache->cachedDylibsImageArray()->startImageNum();
657 context.dyldCache->forEachPatchableUseOfExport(imageIndex, cacheOffsetOfImpl, ^(dyld_cache_patchable_location patchLocation) {
658 uintptr_t* loc = (uintptr_t*)(cacheStart+patchLocation.cacheOffset);
659 #if __has_feature(ptrauth_calls)
660 if ( patchLocation.authenticated ) {
661 dyld3::MachOLoaded::ChainedFixupPointerOnDisk fixupInfo;
662 fixupInfo.arm64e.authRebase.auth = true;
663 fixupInfo.arm64e.authRebase.addrDiv = patchLocation.usesAddressDiversity;
664 fixupInfo.arm64e.authRebase.diversity = patchLocation.discriminator;
665 fixupInfo.arm64e.authRebase.key = patchLocation.key;
666 uintptr_t newValue = fixupInfo.arm64e.signPointer(loc, newImpl + DyldSharedCache::getAddend(patchLocation));
667 if ( *loc != newValue ) {
668 *loc = newValue;
669 if ( context.verboseBind )
670 dyld::log("dyld: cache fixup: *%p = %p (JOP: diversity 0x%04X, addr-div=%d, key=%s) to %s\n",
671 loc, (void*)newValue, patchLocation.discriminator, patchLocation.usesAddressDiversity, DyldSharedCache::keyName(patchLocation), symbolName);
672 }
673 return;
674 }
675 #endif
676 uintptr_t newValue = newImpl + (uintptr_t)DyldSharedCache::getAddend(patchLocation);
677 if ( *loc != newValue ) {
678 *loc = newValue;
679 if ( context.verboseBind )
680 dyld::log("dyld: cache fixup: *%p = %p to %s\n", loc, (void*)newValue, symbolName);
681 }
682 });
683 }
684
685
686
687 uintptr_t ImageLoaderMachOCompressed::resolveWeak(const LinkContext& context, const char* symbolName, bool weak_import,
688 bool runResolver, const ImageLoader** foundIn)
689 {
690 const Symbol* sym;
691 CoalesceNotifier notifier = nullptr;
692 __block uintptr_t foundOutsideCache = 0;
693 __block const char* foundOutsideCachePath = nullptr;
694 __block uintptr_t lastFoundInCache = 0;
695 if ( this->usesChainedFixups() ) {
696 notifier = ^(const Symbol* implSym, const ImageLoader* implIn, const mach_header* implMh) {
697 // This block is only called in dyld2 mode when a non-cached image is search for which weak-def implementation to use
698 // As a side effect of that search we notice any implementations outside and inside the cache,
699 // and use that to trigger patching the cache to use the implementation outside the cache.
700 uintptr_t implAddr = implIn->getExportedSymbolAddress(implSym, context, nullptr, false, symbolName);
701 if ( ((dyld3::MachOLoaded*)implMh)->inDyldCache() ) {
702 if ( foundOutsideCache != 0 ) {
703 // have an implementation in cache and and earlier one not in the cache, patch cache to use earlier one
704 lastFoundInCache = implAddr;
705 uint32_t imageIndex;
706 if ( context.dyldCache->findMachHeaderImageIndex(implMh, imageIndex) ) {
707 const dyld3::closure::Image* overriddenImage = context.dyldCache->cachedDylibsImageArray()->imageForNum(imageIndex+1);
708 uint32_t cacheOffsetOfImpl = (uint32_t)((uintptr_t)implAddr - (uintptr_t)context.dyldCache);
709 if ( context.verboseWeakBind )
710 dyld::log("dyld: weak bind, patching dyld cache uses of %s to use 0x%lX in %s\n", symbolName, foundOutsideCache, foundOutsideCachePath);
711 patchCacheUsesOf(context, overriddenImage, cacheOffsetOfImpl, symbolName, foundOutsideCache);
712 }
713 }
714 }
715 else {
716 // record first non-cache implementation
717 if ( foundOutsideCache == 0 ) {
718 foundOutsideCache = implAddr;
719 foundOutsideCachePath = implIn->getPath();
720 }
721 }
722 };
723 }
724
725 if ( context.coalescedExportFinder(symbolName, &sym, foundIn, notifier) ) {
726 if ( *foundIn != this )
727 context.addDynamicReference(this, const_cast<ImageLoader*>(*foundIn));
728 return (*foundIn)->getExportedSymbolAddress(sym, context, this, runResolver);
729 }
730 // if a bundle is loaded privately the above will not find its exports
731 if ( this->isBundle() && this->hasHiddenExports() ) {
732 // look in self for needed symbol
733 sym = this->findShallowExportedSymbol(symbolName, foundIn);
734 if ( sym != NULL )
735 return (*foundIn)->getExportedSymbolAddress(sym, context, this, runResolver);
736 }
737 if ( weak_import ) {
738 // definition can't be found anywhere, ok because it is weak, just return 0
739 return 0;
740 }
741 throwSymbolNotFound(context, symbolName, this->getPath(), "", "weak");
742 }
743
744
745 uintptr_t ImageLoaderMachOCompressed::resolveTwolevel(const LinkContext& context, const char* symbolName, const ImageLoader* definedInImage,
746 const ImageLoader* requestorImage, unsigned requestorOrdinalOfDef, bool weak_import, bool runResolver,
747 const ImageLoader** foundIn)
748 {
749 // two level lookup
750 uintptr_t address;
751 if ( definedInImage->findExportedSymbolAddress(context, symbolName, requestorImage, requestorOrdinalOfDef, runResolver, foundIn, &address) )
752 return address;
753
754 if ( weak_import ) {
755 // definition can't be found anywhere, ok because it is weak, just return 0
756 return 0;
757 }
758
759 // nowhere to be found, check if maybe this image is too new for this OS
760 char versMismatch[256];
761 versMismatch[0] = '\0';
762 uint32_t imageMinOS = this->minOSVersion();
763 // dyld is always built for the current OS, so we can get the current OS version
764 // from the load command in dyld itself.
765 extern const mach_header __dso_handle;
766 uint32_t dyldMinOS = ImageLoaderMachO::minOSVersion(&__dso_handle);
767 if ( imageMinOS > dyldMinOS ) {
768 #if __MAC_OS_X_VERSION_MIN_REQUIRED
769 const char* msg = dyld::mkstringf(" (which was built for Mac OS X %d.%d)", imageMinOS >> 16, (imageMinOS >> 8) & 0xFF);
770 #else
771 const char* msg = dyld::mkstringf(" (which was built for iOS %d.%d)", imageMinOS >> 16, (imageMinOS >> 8) & 0xFF);
772 #endif
773 strcpy(versMismatch, msg);
774 ::free((void*)msg);
775 }
776 throwSymbolNotFound(context, symbolName, this->getPath(), versMismatch, definedInImage->getPath());
777 }
778
779
780 uintptr_t ImageLoaderMachOCompressed::resolve(const LinkContext& context, const char* symbolName,
781 uint8_t symboFlags, long libraryOrdinal, const ImageLoader** targetImage,
782 LastLookup* last, bool runResolver)
783 {
784 *targetImage = NULL;
785
786 // only clients that benefit from caching last lookup pass in a LastLookup struct
787 if ( last != NULL ) {
788 if ( (last->ordinal == libraryOrdinal)
789 && (last->flags == symboFlags)
790 && (last->name == symbolName) ) {
791 *targetImage = last->foundIn;
792 return last->result;
793 }
794 }
795
796 bool weak_import = (symboFlags & BIND_SYMBOL_FLAGS_WEAK_IMPORT);
797 uintptr_t symbolAddress;
798 if ( context.bindFlat || (libraryOrdinal == BIND_SPECIAL_DYLIB_FLAT_LOOKUP) ) {
799 symbolAddress = this->resolveFlat(context, symbolName, weak_import, runResolver, targetImage);
800 }
801 else if ( libraryOrdinal == BIND_SPECIAL_DYLIB_WEAK_LOOKUP ) {
802 symbolAddress = this->resolveWeak(context, symbolName, false, runResolver, targetImage);
803 }
804 else {
805 if ( libraryOrdinal == BIND_SPECIAL_DYLIB_MAIN_EXECUTABLE ) {
806 *targetImage = context.mainExecutable;
807 }
808 else if ( libraryOrdinal == BIND_SPECIAL_DYLIB_SELF ) {
809 *targetImage = this;
810 }
811 else if ( libraryOrdinal <= 0 ) {
812 dyld::throwf("bad mach-o binary, unknown special library ordinal (%ld) too big for symbol %s in %s",
813 libraryOrdinal, symbolName, this->getPath());
814 }
815 else if ( (unsigned)libraryOrdinal <= libraryCount() ) {
816 *targetImage = libImage((unsigned int)libraryOrdinal-1);
817 }
818 else {
819 dyld::throwf("bad mach-o binary, library ordinal (%ld) too big (max %u) for symbol %s in %s",
820 libraryOrdinal, libraryCount(), symbolName, this->getPath());
821 }
822 if ( *targetImage == NULL ) {
823 if ( weak_import ) {
824 // if target library not loaded and reference is weak or library is weak return 0
825 symbolAddress = 0;
826 }
827 else {
828 dyld::throwf("can't resolve symbol %s in %s because dependent dylib #%ld could not be loaded",
829 symbolName, this->getPath(), libraryOrdinal);
830 }
831 }
832 else {
833 symbolAddress = resolveTwolevel(context, symbolName, *targetImage, this, (unsigned)libraryOrdinal, weak_import, runResolver, targetImage);
834 }
835 }
836
837 // save off lookup results if client wants
838 if ( last != NULL ) {
839 last->ordinal = libraryOrdinal;
840 last->flags = symboFlags;
841 last->name = symbolName;
842 last->foundIn = *targetImage;
843 last->result = symbolAddress;
844 }
845
846 return symbolAddress;
847 }
848
849 uintptr_t ImageLoaderMachOCompressed::bindAt(const LinkContext& context, ImageLoaderMachOCompressed* image,
850 uintptr_t addr, uint8_t type, const char* symbolName,
851 uint8_t symbolFlags, intptr_t addend, long libraryOrdinal,
852 ExtraBindData *extraBindData,
853 const char* msg, LastLookup* last, bool runResolver)
854 {
855 const ImageLoader* targetImage;
856 uintptr_t symbolAddress;
857
858 // resolve symbol
859 if (type == BIND_TYPE_THREADED_REBASE) {
860 symbolAddress = 0;
861 targetImage = nullptr;
862 } else
863 symbolAddress = image->resolve(context, symbolName, symbolFlags, libraryOrdinal, &targetImage, last, runResolver);
864
865 // do actual update
866 return image->bindLocation(context, image->imageBaseAddress(), addr, symbolAddress, type, symbolName, addend, image->getPath(), targetImage ? targetImage->getPath() : NULL, msg, extraBindData, image->fSlide);
867 }
868
869
870 void ImageLoaderMachOCompressed::throwBadBindingAddress(uintptr_t address, uintptr_t segmentEndAddress, int segmentIndex,
871 const uint8_t* startOpcodes, const uint8_t* endOpcodes, const uint8_t* pos)
872 {
873 dyld::throwf("malformed binding opcodes (%ld/%ld): address 0x%08lX is outside segment %s (0x%08lX -> 0x%08lX)",
874 (intptr_t)(pos-startOpcodes), (intptr_t)(endOpcodes-startOpcodes), address, segName(segmentIndex),
875 segActualLoadAddress(segmentIndex), segmentEndAddress);
876 }
877
878
879 void ImageLoaderMachOCompressed::doBind(const LinkContext& context, bool forceLazysBound)
880 {
881 CRSetCrashLogMessage2(this->getPath());
882
883 // if prebound and loaded at prebound address, and all libraries are same as when this was prebound, then no need to bind
884 // note: flat-namespace binaries need to have imports rebound (even if correctly prebound)
885 if ( this->usablePrebinding(context) ) {
886 // don't need to bind
887 // except weak which may now be inline with the regular binds
888 if (this->participatesInCoalescing()) {
889 // run through all binding opcodes
890 eachBind(context, ^(const LinkContext& ctx, ImageLoaderMachOCompressed* image,
891 uintptr_t addr, uint8_t type, const char* symbolName,
892 uint8_t symbolFlags, intptr_t addend, long libraryOrdinal,
893 ExtraBindData *extraBindData,
894 const char* msg, LastLookup* last, bool runResolver) {
895 if ( libraryOrdinal != BIND_SPECIAL_DYLIB_WEAK_LOOKUP )
896 return (uintptr_t)0;
897 return ImageLoaderMachOCompressed::bindAt(ctx, image, addr, type, symbolName, symbolFlags,
898 addend, libraryOrdinal, extraBindData,
899 msg, last, runResolver);
900 });
901 }
902 }
903 else {
904 uint64_t t0 = mach_absolute_time();
905
906 uint32_t ignore;
907 bool bindingBecauseOfRoot = ( this->overridesCachedDylib(ignore) || this->inSharedCache() );
908 vmAccountingSetSuspended(context, bindingBecauseOfRoot);
909
910 if ( fChainedFixups != NULL ) {
911 const dyld_chained_fixups_header* fixupsHeader = (dyld_chained_fixups_header*)(fLinkEditBase + fChainedFixups->dataoff);
912 doApplyFixups(context, fixupsHeader);
913 }
914 else {
915 #if TEXT_RELOC_SUPPORT
916 // if there are __TEXT fixups, temporarily make __TEXT writable
917 if ( fTextSegmentBinds )
918 this->makeTextSegmentWritable(context, true);
919 #endif
920
921 // run through all binding opcodes
922 eachBind(context, ^(const LinkContext& ctx, ImageLoaderMachOCompressed* image,
923 uintptr_t addr, uint8_t type, const char* symbolName,
924 uint8_t symbolFlags, intptr_t addend, long libraryOrdinal,
925 ExtraBindData *extraBindData,
926 const char* msg, LastLookup* last, bool runResolver) {
927 return ImageLoaderMachOCompressed::bindAt(ctx, image, addr, type, symbolName, symbolFlags,
928 addend, libraryOrdinal, extraBindData,
929 msg, last, runResolver);
930 });
931
932 #if TEXT_RELOC_SUPPORT
933 // if there were __TEXT fixups, restore write protection
934 if ( fTextSegmentBinds )
935 this->makeTextSegmentWritable(context, false);
936 #endif
937
938 // if this image is in the shared cache, but depends on something no longer in the shared cache,
939 // there is no way to reset the lazy pointers, so force bind them now
940 if ( forceLazysBound || fInSharedCache )
941 this->doBindJustLazies(context);
942
943 // this image is in cache, but something below it is not. If
944 // this image has lazy pointer to a resolver function, then
945 // the stub may have been altered to point to a shared lazy pointer.
946 if ( fInSharedCache )
947 this->updateOptimizedLazyPointers(context);
948 }
949
950 uint64_t t1 = mach_absolute_time();
951 ImageLoader::fgTotalRebindCacheTime += (t1-t0);
952 }
953
954 // See if this dylib overrides something in the dyld cache
955 uint32_t dyldCacheOverrideImageNum;
956 if ( context.dyldCache && context.dyldCache->header.builtFromChainedFixups && overridesCachedDylib(dyldCacheOverrideImageNum) ) {
957 // need to patch all other places in cache that point to the overridden dylib, to point to this dylib instead
958 const dyld3::closure::Image* overriddenImage = context.dyldCache->cachedDylibsImageArray()->imageForNum(dyldCacheOverrideImageNum);
959 uint32_t imageIndex = dyldCacheOverrideImageNum - (uint32_t)context.dyldCache->cachedDylibsImageArray()->startImageNum();
960 context.dyldCache->forEachPatchableExport(imageIndex, ^(uint32_t cacheOffsetOfImpl, const char* exportName) {
961 uintptr_t newImpl = 0;
962 const ImageLoader* foundIn;
963 this->findExportedSymbolAddress(context, exportName, NULL, 0, false, &foundIn, &newImpl);
964 patchCacheUsesOf(context, overriddenImage, cacheOffsetOfImpl, exportName, newImpl);
965 });
966 }
967
968 // set up dyld entry points in image
969 // do last so flat main executables will have __dyld or __program_vars set up
970 this->setupLazyPointerHandler(context);
971 CRSetCrashLogMessage2(NULL);
972 }
973
974
975 void ImageLoaderMachOCompressed::doBindJustLazies(const LinkContext& context)
976 {
977 eachLazyBind(context, ^(const LinkContext& ctx, ImageLoaderMachOCompressed* image,
978 uintptr_t addr, uint8_t type, const char* symbolName,
979 uint8_t symbolFlags, intptr_t addend, long libraryOrdinal,
980 ExtraBindData *extraBindData,
981 const char* msg, LastLookup* last, bool runResolver) {
982 return ImageLoaderMachOCompressed::bindAt(ctx, image, addr, type, symbolName, symbolFlags,
983 addend, libraryOrdinal, extraBindData,
984 msg, last, runResolver);
985 });
986 }
987
988 void ImageLoaderMachOCompressed::doApplyFixups(const LinkContext& context, const dyld_chained_fixups_header* fixupsHeader)
989 {
990 const dyld3::MachOLoaded* ml = (dyld3::MachOLoaded*)machHeader();
991 const dyld_chained_starts_in_image* starts = (dyld_chained_starts_in_image*)((uint8_t*)fixupsHeader + fixupsHeader->starts_offset);
992
993 // build table of resolved targets for each symbol ordinal
994 STACK_ALLOC_OVERFLOW_SAFE_ARRAY(const void*, targetAddrs, 128);
995 targetAddrs.reserve(fixupsHeader->imports_count);
996 Diagnostics diag;
997 const dyld3::MachOAnalyzer* ma = (dyld3::MachOAnalyzer*)ml;
998 ma->forEachChainedFixupTarget(diag, ^(int libOrdinal, const char* symbolName, uint64_t addend, bool weakImport, bool& stop) {
999 const ImageLoader* targetImage;
1000 uint8_t symbolFlags = weakImport ? BIND_SYMBOL_FLAGS_WEAK_IMPORT : 0;
1001 uintptr_t symbolAddress = this->resolve(context, symbolName, symbolFlags, libOrdinal, &targetImage, NULL, true);
1002 targetAddrs.push_back((void*)(symbolAddress + addend));
1003 });
1004
1005 auto logFixups = ^(void* loc, void* newValue) {
1006 dyld::log("dyld: fixup: %s:%p = %p\n", this->getShortName(), loc, newValue);
1007 };
1008 if ( !context.verboseBind )
1009 logFixups = nullptr;
1010
1011 ml->fixupAllChainedFixups(diag, starts, fSlide, targetAddrs, logFixups);
1012 }
1013
1014 void ImageLoaderMachOCompressed::registerInterposing(const LinkContext& context)
1015 {
1016 // mach-o files advertise interposing by having a __DATA __interpose section
1017 struct InterposeData { uintptr_t replacement; uintptr_t replacee; };
1018
1019 __block Diagnostics diag;
1020 const dyld3::MachOAnalyzer* ma = (dyld3::MachOAnalyzer*)fMachOData;
1021 ma->forEachInterposingSection(diag, ^(uint64_t vmOffset, uint64_t vmSize, bool& stopSections) {
1022 if ( ma->hasChainedFixups() ) {
1023 const uint16_t pointerFormat = ma->chainedPointerFormat();
1024 const uint8_t* sectionStart = fMachOData+vmOffset;
1025 const uint8_t* sectionEnd = fMachOData+vmOffset+vmSize;
1026 ma->withChainStarts(diag, ma->chainStartsOffset(), ^(const dyld_chained_starts_in_image* startsInfo) {
1027 __block uintptr_t lastRebaseTarget = 0;
1028 ma->forEachFixupInAllChains(diag, startsInfo, false, ^(dyld3::MachOLoaded::ChainedFixupPointerOnDisk* fixupLoc, const dyld_chained_starts_in_segment* segInfo, bool& stopFixups) {
1029 if ( ((uint8_t*)fixupLoc < sectionStart) || ((uint8_t*)fixupLoc >= sectionEnd) )
1030 return;
1031 uint64_t rebaseTargetRuntimeOffset;
1032 uint32_t bindOrdinal;
1033 if ( fixupLoc->isRebase(pointerFormat, 0, rebaseTargetRuntimeOffset) ) {
1034 //dyld::log("interpose rebase at fixup at %p to 0x%0llX\n", fixupLoc, rebaseTargetRuntimeOffset);
1035 lastRebaseTarget = (uintptr_t)(fMachOData+rebaseTargetRuntimeOffset);
1036 }
1037 else if ( fixupLoc->isBind(pointerFormat, bindOrdinal) ) {
1038 //dyld::log("interpose bind fixup at %p to bind ordinal %d\n", fixupLoc, bindOrdinal);
1039 __block uint32_t targetBindIndex = 0;
1040 ma->forEachChainedFixupTarget(diag, ^(int libraryOrdinal, const char* symbolName, uint64_t addend, bool weakImport, bool& stop) {
1041 if ( targetBindIndex == bindOrdinal ) {
1042 //dyld::log("interpose bind fixup at %p is to %s libOrdinal=%d\n", fixupLoc, symbolName, libraryOrdinal);
1043 LastLookup* last = NULL;
1044 const ImageLoader* targetImage;
1045 uintptr_t targetBindAddress = 0;
1046 try {
1047 targetBindAddress = this->resolve(context, symbolName, 0, libraryOrdinal, &targetImage, last, false);
1048 }
1049 catch (const char* msg) {
1050 if ( !weakImport )
1051 throw msg;
1052 targetBindAddress = 0;
1053 }
1054 //dyld::log("interpose bind fixup at %p is bound to 0x%lX\n", fixupLoc, targetBindAddress);
1055 // <rdar://problem/25686570> ignore interposing on a weak function that does not exist
1056 if ( targetBindAddress == 0 )
1057 return;
1058 ImageLoader::InterposeTuple tuple;
1059 tuple.replacement = lastRebaseTarget;
1060 tuple.neverImage = this;
1061 tuple.onlyImage = NULL;
1062 tuple.replacee = targetBindAddress;
1063 // <rdar://problem/7937695> verify that replacement is in this image
1064 if ( this->containsAddress((void*)tuple.replacement) ) {
1065 if ( context.verboseInterposing )
1066 dyld::log("dyld: interposing 0x%lx with 0x%lx\n", tuple.replacee, tuple.replacement);
1067 // chain to any existing interpositions
1068 for (std::vector<InterposeTuple>::iterator it=fgInterposingTuples.begin(); it != fgInterposingTuples.end(); it++) {
1069 if ( it->replacee == tuple.replacee ) {
1070 tuple.replacee = it->replacement;
1071 }
1072 }
1073 ImageLoader::fgInterposingTuples.push_back(tuple);
1074 }
1075 }
1076 ++targetBindIndex;
1077 });
1078 }
1079 });
1080 });
1081 }
1082 else {
1083 // traditional (non-chained) fixups
1084 const size_t count = (size_t)(vmSize / sizeof(InterposeData));
1085 const InterposeData* interposeArray = (InterposeData*)(fMachOData+vmOffset);
1086 if ( context.verboseInterposing )
1087 dyld::log("dyld: found %lu interposing tuples in %s\n", count, getPath());
1088 for (size_t j=0; j < count; ++j) {
1089 uint64_t bindOffset = ((uint8_t*)&(interposeArray[j].replacee)) - fMachOData;
1090 ma->forEachBind(diag, ^(uint64_t runtimeOffset, int libOrdinal, const char* symbolName, bool weakImport, bool lazyBind, uint64_t addend, bool& stopBinds) {
1091 if ( bindOffset != runtimeOffset )
1092 return;
1093 stopBinds = true;
1094 LastLookup* last = NULL;
1095 const ImageLoader* targetImage;
1096 uintptr_t targetBindAddress = 0;
1097 try {
1098 targetBindAddress = this->resolve(context, symbolName, 0, libOrdinal, &targetImage, last, false);
1099 }
1100 catch (const char* msg) {
1101 if ( !weakImport )
1102 throw msg;
1103 targetBindAddress = 0;
1104 }
1105 ImageLoader::InterposeTuple tuple;
1106 tuple.replacement = interposeArray[j].replacement;
1107 tuple.neverImage = this;
1108 tuple.onlyImage = NULL;
1109 tuple.replacee = targetBindAddress;
1110 // <rdar://problem/25686570> ignore interposing on a weak function that does not exist
1111 if ( tuple.replacee == 0 )
1112 return;
1113 // <rdar://problem/7937695> verify that replacement is in this image
1114 if ( this->containsAddress((void*)tuple.replacement) ) {
1115 if ( context.verboseInterposing )
1116 dyld::log("dyld: interposing 0x%lx with 0x%lx\n", tuple.replacee, tuple.replacement);
1117 // chain to any existing interpositions
1118 for (std::vector<InterposeTuple>::iterator it=fgInterposingTuples.begin(); it != fgInterposingTuples.end(); it++) {
1119 if ( it->replacee == tuple.replacee ) {
1120 tuple.replacee = it->replacement;
1121 }
1122 }
1123 ImageLoader::fgInterposingTuples.push_back(tuple);
1124 }
1125 }, ^(const char* symbolName){ },
1126 ^() { });
1127 }
1128 }
1129 });
1130 }
1131
1132 bool ImageLoaderMachOCompressed::usesChainedFixups() const
1133 {
1134 return ((dyld3::MachOLoaded*)machHeader())->hasChainedFixups();
1135 }
1136
1137 struct ThreadedBindData {
1138 ThreadedBindData(const char* symbolName, int64_t addend, long libraryOrdinal, uint8_t symbolFlags, uint8_t type)
1139 : symbolName(symbolName), addend(addend), libraryOrdinal(libraryOrdinal), symbolFlags(symbolFlags), type(type) { }
1140
1141 std::tuple<const char*, int64_t, long, bool, uint8_t> pack() const {
1142 return std::make_tuple(symbolName, addend, libraryOrdinal, symbolFlags, type);
1143 }
1144
1145 const char* symbolName = nullptr;
1146 int64_t addend = 0;
1147 long libraryOrdinal = 0;
1148 uint8_t symbolFlags = 0;
1149 uint8_t type = 0;
1150 };
1151
1152 void ImageLoaderMachOCompressed::makeDataReadOnly() const
1153 {
1154 #if !TEXT_RELOC_SUPPORT
1155 if ( fReadOnlyDataSegment && !this->ImageLoader::inSharedCache() ) {
1156 for (unsigned int i=0; i < fSegmentsCount; ++i) {
1157 if ( segIsReadOnlyData(i) ) {
1158 uintptr_t start = segActualLoadAddress(i);
1159 uintptr_t size = segSize(i);
1160 ::mprotect((void*)start, size, PROT_READ);
1161 //dyld::log("make read-only 0x%09lX -> 0x%09lX\n", (long)start, (long)(start+size));
1162 }
1163 }
1164 }
1165 #endif
1166 }
1167
1168
1169 void ImageLoaderMachOCompressed::eachBind(const LinkContext& context, bind_handler handler)
1170 {
1171 try {
1172 uint8_t type = 0;
1173 int segmentIndex = -1;
1174 uintptr_t address = segActualLoadAddress(0);
1175 uintptr_t segmentStartAddress = segActualLoadAddress(0);
1176 uintptr_t segmentEndAddress = segActualEndAddress(0);
1177 const char* symbolName = NULL;
1178 uint8_t symboFlags = 0;
1179 bool libraryOrdinalSet = false;
1180 long libraryOrdinal = 0;
1181 intptr_t addend = 0;
1182 uintptr_t count;
1183 uintptr_t skip;
1184 uintptr_t segOffset = 0;
1185
1186 dyld3::OverflowSafeArray<ThreadedBindData> ordinalTable;
1187 bool useThreadedRebaseBind = false;
1188 ExtraBindData extraBindData;
1189 LastLookup last = { 0, 0, NULL, 0, NULL };
1190 const uint8_t* const start = fLinkEditBase + fDyldInfo->bind_off;
1191 const uint8_t* const end = &start[fDyldInfo->bind_size];
1192 const uint8_t* p = start;
1193 bool done = false;
1194 while ( !done && (p < end) ) {
1195 uint8_t immediate = *p & BIND_IMMEDIATE_MASK;
1196 uint8_t opcode = *p & BIND_OPCODE_MASK;
1197 ++p;
1198 switch (opcode) {
1199 case BIND_OPCODE_DONE:
1200 done = true;
1201 break;
1202 case BIND_OPCODE_SET_DYLIB_ORDINAL_IMM:
1203 libraryOrdinal = immediate;
1204 libraryOrdinalSet = true;
1205 break;
1206 case BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB:
1207 libraryOrdinal = read_uleb128(p, end);
1208 libraryOrdinalSet = true;
1209 break;
1210 case BIND_OPCODE_SET_DYLIB_SPECIAL_IMM:
1211 // the special ordinals are negative numbers
1212 if ( immediate == 0 )
1213 libraryOrdinal = 0;
1214 else {
1215 int8_t signExtended = BIND_OPCODE_MASK | immediate;
1216 libraryOrdinal = signExtended;
1217 }
1218 libraryOrdinalSet = true;
1219 break;
1220 case BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
1221 symbolName = (char*)p;
1222 symboFlags = immediate;
1223 while (*p != '\0')
1224 ++p;
1225 ++p;
1226 break;
1227 case BIND_OPCODE_SET_TYPE_IMM:
1228 type = immediate;
1229 break;
1230 case BIND_OPCODE_SET_ADDEND_SLEB:
1231 addend = read_sleb128(p, end);
1232 break;
1233 case BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
1234 segmentIndex = immediate;
1235 if ( (segmentIndex >= fSegmentsCount) || (segmentIndex < 0) )
1236 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is out of range (0..%d)",
1237 segmentIndex, fSegmentsCount-1);
1238 #if TEXT_RELOC_SUPPORT
1239 if ( !segWriteable(segmentIndex) && !segHasRebaseFixUps(segmentIndex) && !segHasBindFixUps(segmentIndex) )
1240 #else
1241 if ( !segWriteable(segmentIndex) )
1242 #endif
1243 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is not writable", segmentIndex);
1244 segOffset = read_uleb128(p, end);
1245 if ( segOffset > segSize(segmentIndex) )
1246 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has offset 0x%08lX beyond segment size (0x%08lX)", segOffset, segSize(segmentIndex));
1247 segmentStartAddress = segActualLoadAddress(segmentIndex);
1248 address = segmentStartAddress + segOffset;
1249 segmentEndAddress = segActualEndAddress(segmentIndex);
1250 break;
1251 case BIND_OPCODE_ADD_ADDR_ULEB:
1252 address += read_uleb128(p, end);
1253 break;
1254 case BIND_OPCODE_DO_BIND:
1255 if (!useThreadedRebaseBind) {
1256 if ( (address < segmentStartAddress) || (address >= segmentEndAddress) )
1257 throwBadBindingAddress(address, segmentEndAddress, segmentIndex, start, end, p);
1258 if ( symbolName == NULL )
1259 dyld::throwf("BIND_OPCODE_DO_BIND missing preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM");
1260 if ( segmentIndex == -1 )
1261 dyld::throwf("BIND_OPCODE_DO_BIND missing preceding BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB");
1262 if ( !libraryOrdinalSet )
1263 dyld::throwf("BIND_OPCODE_DO_BIND missing preceding BIND_OPCODE_SET_DYLIB_ORDINAL*");
1264 handler(context, this, address, type, symbolName, symboFlags, addend, libraryOrdinal,
1265 &extraBindData, "", &last, false);
1266 address += sizeof(intptr_t);
1267 } else {
1268 ordinalTable.push_back(ThreadedBindData(symbolName, addend, libraryOrdinal, symboFlags, type));
1269 }
1270 break;
1271 case BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB:
1272 if ( (address < segmentStartAddress) || (address >= segmentEndAddress) )
1273 throwBadBindingAddress(address, segmentEndAddress, segmentIndex, start, end, p);
1274 if ( symbolName == NULL )
1275 dyld::throwf("BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB missing preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM");
1276 if ( segmentIndex == -1 )
1277 dyld::throwf("BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB missing preceding BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB");
1278 if ( !libraryOrdinalSet )
1279 dyld::throwf("BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB missing preceding BIND_OPCODE_SET_DYLIB_ORDINAL*");
1280 handler(context, this, address, type, symbolName, symboFlags, addend, libraryOrdinal,
1281 &extraBindData, "", &last, false);
1282 address += read_uleb128(p, end) + sizeof(intptr_t);
1283 break;
1284 case BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED:
1285 if ( (address < segmentStartAddress) || (address >= segmentEndAddress) )
1286 throwBadBindingAddress(address, segmentEndAddress, segmentIndex, start, end, p);
1287 if ( symbolName == NULL )
1288 dyld::throwf("BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED missing preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM");
1289 if ( segmentIndex == -1 )
1290 dyld::throwf("BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED missing preceding BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB");
1291 if ( !libraryOrdinalSet )
1292 dyld::throwf("BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED missing preceding BIND_OPCODE_SET_DYLIB_ORDINAL*");
1293 handler(context, this, address, type, symbolName, symboFlags, addend, libraryOrdinal,
1294 &extraBindData, "", &last, false);
1295 address += immediate*sizeof(intptr_t) + sizeof(intptr_t);
1296 break;
1297 case BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB:
1298 if ( symbolName == NULL )
1299 dyld::throwf("BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB missing preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM");
1300 if ( segmentIndex == -1 )
1301 dyld::throwf("BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB missing preceding BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB");
1302 count = read_uleb128(p, end);
1303 if ( !libraryOrdinalSet )
1304 dyld::throwf("BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB missing preceding BIND_OPCODE_SET_DYLIB_ORDINAL*");
1305 skip = read_uleb128(p, end);
1306 for (uint32_t i=0; i < count; ++i) {
1307 if ( (address < segmentStartAddress) || (address >= segmentEndAddress) )
1308 throwBadBindingAddress(address, segmentEndAddress, segmentIndex, start, end, p);
1309 handler(context, this, address, type, symbolName, symboFlags, addend, libraryOrdinal,
1310 &extraBindData, "", &last, false);
1311 address += skip + sizeof(intptr_t);
1312 }
1313 break;
1314 case BIND_OPCODE_THREADED:
1315 if (sizeof(intptr_t) != 8) {
1316 dyld::throwf("BIND_OPCODE_THREADED require 64-bit");
1317 return;
1318 }
1319 // Note the immediate is a sub opcode
1320 switch (immediate) {
1321 case BIND_SUBOPCODE_THREADED_SET_BIND_ORDINAL_TABLE_SIZE_ULEB:
1322 count = read_uleb128(p, end);
1323 ordinalTable.clear();
1324 // FIXME: ld64 wrote the wrong value here and we need to offset by 1 for now.
1325 ordinalTable.reserve(count + 1);
1326 useThreadedRebaseBind = true;
1327 break;
1328 case BIND_SUBOPCODE_THREADED_APPLY: {
1329 uint64_t delta = 0;
1330 do {
1331 address = segmentStartAddress + segOffset;
1332 uint64_t value = *(uint64_t*)address;
1333
1334
1335 bool isRebase = (value & (1ULL << 62)) == 0;
1336 if (isRebase) {
1337 {
1338 // Call the bind handler which knows about our bind type being set to rebase
1339 handler(context, this, address, BIND_TYPE_THREADED_REBASE, nullptr, 0, 0, 0,
1340 nullptr, "", &last, false);
1341 }
1342 } else {
1343 // the ordinal is bits [0..15]
1344 uint16_t ordinal = value & 0xFFFF;
1345 if (ordinal >= ordinalTable.count()) {
1346 dyld::throwf("bind ordinal (%d) is out of range (max=%lu) for disk pointer 0x%16llX at segIndex=%d, segOffset=0x%0lX in %s",
1347 ordinal, ordinalTable.count(),value, segmentIndex, segOffset, this->getPath());
1348 return;
1349 }
1350 std::tie(symbolName, addend, libraryOrdinal, symboFlags, type) = ordinalTable[ordinal].pack();
1351 if ( (address < segmentStartAddress) || (address >= segmentEndAddress) )
1352 throwBadBindingAddress(address, segmentEndAddress, segmentIndex, start, end, p);
1353 {
1354 handler(context, this, address, BIND_TYPE_THREADED_BIND,
1355 symbolName, symboFlags, addend, libraryOrdinal,
1356 nullptr, "", &last, false);
1357 }
1358 }
1359
1360 // The delta is bits [51..61]
1361 // And bit 62 is to tell us if we are a rebase (0) or bind (1)
1362 value &= ~(1ULL << 62);
1363 delta = ( value & 0x3FF8000000000000 ) >> 51;
1364 segOffset += delta * sizeof(intptr_t);
1365 } while ( delta != 0 );
1366 break;
1367 }
1368
1369 default:
1370 dyld::throwf("bad threaded bind subopcode 0x%02X", *p);
1371 }
1372 break;
1373 default:
1374 dyld::throwf("bad bind opcode %d in bind info", *p);
1375 }
1376 }
1377 }
1378 catch (const char* msg) {
1379 const char* newMsg = dyld::mkstringf("%s in %s", msg, this->getPath());
1380 free((void*)msg);
1381 throw newMsg;
1382 }
1383 }
1384
1385 void ImageLoaderMachOCompressed::eachLazyBind(const LinkContext& context, bind_handler handler)
1386 {
1387 try {
1388 uint8_t type = BIND_TYPE_POINTER;
1389 int segmentIndex = -1;
1390 uintptr_t address = segActualLoadAddress(0);
1391 uintptr_t segmentStartAddress = segActualLoadAddress(0);
1392 uintptr_t segmentEndAddress = segActualEndAddress(0);
1393 uintptr_t segOffset;
1394 const char* symbolName = NULL;
1395 uint8_t symboFlags = 0;
1396 long libraryOrdinal = 0;
1397 intptr_t addend = 0;
1398 const uint8_t* const start = fLinkEditBase + fDyldInfo->lazy_bind_off;
1399 const uint8_t* const end = &start[fDyldInfo->lazy_bind_size];
1400 const uint8_t* p = start;
1401 bool done = false;
1402 while ( !done && (p < end) ) {
1403 uint8_t immediate = *p & BIND_IMMEDIATE_MASK;
1404 uint8_t opcode = *p & BIND_OPCODE_MASK;
1405 ++p;
1406 switch (opcode) {
1407 case BIND_OPCODE_DONE:
1408 // there is BIND_OPCODE_DONE at end of each lazy bind, don't stop until end of whole sequence
1409 break;
1410 case BIND_OPCODE_SET_DYLIB_ORDINAL_IMM:
1411 libraryOrdinal = immediate;
1412 break;
1413 case BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB:
1414 libraryOrdinal = read_uleb128(p, end);
1415 break;
1416 case BIND_OPCODE_SET_DYLIB_SPECIAL_IMM:
1417 // the special ordinals are negative numbers
1418 if ( immediate == 0 )
1419 libraryOrdinal = 0;
1420 else {
1421 int8_t signExtended = BIND_OPCODE_MASK | immediate;
1422 libraryOrdinal = signExtended;
1423 }
1424 break;
1425 case BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
1426 symbolName = (char*)p;
1427 symboFlags = immediate;
1428 while (*p != '\0')
1429 ++p;
1430 ++p;
1431 break;
1432 case BIND_OPCODE_SET_TYPE_IMM:
1433 type = immediate;
1434 break;
1435 case BIND_OPCODE_SET_ADDEND_SLEB:
1436 addend = read_sleb128(p, end);
1437 break;
1438 case BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
1439 segmentIndex = immediate;
1440 if ( (segmentIndex >= fSegmentsCount) || (segmentIndex < 0) )
1441 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is out of range (0..%d)",
1442 segmentIndex, fSegmentsCount-1);
1443 if ( !segWriteable(segmentIndex) )
1444 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is not writable", segmentIndex);
1445 segOffset = read_uleb128(p, end);
1446 if ( segOffset > segSize(segmentIndex) )
1447 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has offset 0x%08lX beyond segment size (0x%08lX)", segOffset, segSize(segmentIndex));
1448 segmentStartAddress = segActualLoadAddress(segmentIndex);
1449 segmentEndAddress = segActualEndAddress(segmentIndex);
1450 address = segmentStartAddress + segOffset;
1451 break;
1452 case BIND_OPCODE_ADD_ADDR_ULEB:
1453 address += read_uleb128(p, end);
1454 break;
1455 case BIND_OPCODE_DO_BIND:
1456 if ( segmentIndex == -1 )
1457 dyld::throwf("BIND_OPCODE_DO_BIND missing preceding BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB");
1458 if ( (address < segmentStartAddress) || (address >= segmentEndAddress) )
1459 throwBadBindingAddress(address, segmentEndAddress, segmentIndex, start, end, p);
1460 if ( symbolName == NULL )
1461 dyld::throwf("BIND_OPCODE_DO_BIND missing preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM");
1462 handler(context, this, address, type, symbolName, symboFlags, addend, libraryOrdinal,
1463 NULL, "forced lazy ", NULL, false);
1464 address += sizeof(intptr_t);
1465 break;
1466 case BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB:
1467 case BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED:
1468 case BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB:
1469 default:
1470 dyld::throwf("bad lazy bind opcode %d", *p);
1471 }
1472 }
1473 }
1474
1475 catch (const char* msg) {
1476 const char* newMsg = dyld::mkstringf("%s in %s", msg, this->getPath());
1477 free((void*)msg);
1478 throw newMsg;
1479 }
1480 }
1481
1482 // A program built targeting 10.5 will have hybrid stubs. When used with weak symbols
1483 // the classic lazy loader is used even when running on 10.6
1484 uintptr_t ImageLoaderMachOCompressed::doBindLazySymbol(uintptr_t* lazyPointer, const LinkContext& context)
1485 {
1486 // only works with compressed LINKEDIT if classic symbol table is also present
1487 const macho_nlist* symbolTable = NULL;
1488 const char* symbolTableStrings = NULL;
1489 const dysymtab_command* dynSymbolTable = NULL;
1490 const uint32_t cmd_count = ((macho_header*)fMachOData)->ncmds;
1491 const struct load_command* const cmds = (struct load_command*)&fMachOData[sizeof(macho_header)];
1492 const struct load_command* cmd = cmds;
1493 for (uint32_t i = 0; i < cmd_count; ++i) {
1494 switch (cmd->cmd) {
1495 case LC_SYMTAB:
1496 {
1497 const struct symtab_command* symtab = (struct symtab_command*)cmd;
1498 symbolTableStrings = (const char*)&fLinkEditBase[symtab->stroff];
1499 symbolTable = (macho_nlist*)(&fLinkEditBase[symtab->symoff]);
1500 }
1501 break;
1502 case LC_DYSYMTAB:
1503 dynSymbolTable = (struct dysymtab_command*)cmd;
1504 break;
1505 }
1506 cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
1507 }
1508 // no symbol table => no lookup by address
1509 if ( (symbolTable == NULL) || (dynSymbolTable == NULL) )
1510 dyld::throwf("classic lazy binding used with compressed LINKEDIT at %p in image %s", lazyPointer, this->getPath());
1511
1512 // scan for all lazy-pointer sections
1513 const bool twoLevel = this->usesTwoLevelNameSpace();
1514 const uint32_t* const indirectTable = (uint32_t*)&fLinkEditBase[dynSymbolTable->indirectsymoff];
1515 cmd = cmds;
1516 for (uint32_t i = 0; i < cmd_count; ++i) {
1517 switch (cmd->cmd) {
1518 case LC_SEGMENT_COMMAND:
1519 {
1520 const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
1521 const struct macho_section* const sectionsStart = (struct macho_section*)((char*)seg + sizeof(struct macho_segment_command));
1522 const struct macho_section* const sectionsEnd = &sectionsStart[seg->nsects];
1523 for (const struct macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
1524 const uint8_t type = sect->flags & SECTION_TYPE;
1525 uint32_t symbolIndex = INDIRECT_SYMBOL_LOCAL;
1526 if ( type == S_LAZY_SYMBOL_POINTERS ) {
1527 const size_t pointerCount = sect->size / sizeof(uintptr_t);
1528 uintptr_t* const symbolPointers = (uintptr_t*)(sect->addr + fSlide);
1529 if ( (lazyPointer >= symbolPointers) && (lazyPointer < &symbolPointers[pointerCount]) ) {
1530 const uint32_t indirectTableOffset = sect->reserved1;
1531 const size_t lazyIndex = lazyPointer - symbolPointers;
1532 symbolIndex = indirectTable[indirectTableOffset + lazyIndex];
1533 }
1534 }
1535 if ( (symbolIndex != INDIRECT_SYMBOL_ABS) && (symbolIndex != INDIRECT_SYMBOL_LOCAL) ) {
1536 const macho_nlist* symbol = &symbolTable[symbolIndex];
1537 const char* symbolName = &symbolTableStrings[symbol->n_un.n_strx];
1538 int libraryOrdinal = GET_LIBRARY_ORDINAL(symbol->n_desc);
1539 if ( !twoLevel || context.bindFlat )
1540 libraryOrdinal = BIND_SPECIAL_DYLIB_FLAT_LOOKUP;
1541 uintptr_t ptrToBind = (uintptr_t)lazyPointer;
1542 uintptr_t symbolAddr = bindAt(context, this, ptrToBind, BIND_TYPE_POINTER, symbolName, 0, 0, libraryOrdinal,
1543 NULL, "lazy ", NULL);
1544 ++fgTotalLazyBindFixups;
1545 return symbolAddr;
1546 }
1547 }
1548 }
1549 break;
1550 }
1551 cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
1552 }
1553 dyld::throwf("lazy pointer not found at address %p in image %s", lazyPointer, this->getPath());
1554 }
1555
1556
1557
1558 uintptr_t ImageLoaderMachOCompressed::doBindFastLazySymbol(uint32_t lazyBindingInfoOffset, const LinkContext& context,
1559 void (*lock)(), void (*unlock)())
1560 {
1561 // <rdar://problem/8663923> race condition with flat-namespace lazy binding
1562 if ( this->usesTwoLevelNameSpace() ) {
1563 // two-level namespace lookup does not require lock because dependents can't be unloaded before this image
1564 }
1565 else {
1566 // acquire dyld global lock
1567 if ( lock != NULL )
1568 lock();
1569 }
1570
1571 const uint8_t* const start = fLinkEditBase + fDyldInfo->lazy_bind_off;
1572 const uint8_t* const end = &start[fDyldInfo->lazy_bind_size];
1573 uint8_t segIndex;
1574 uintptr_t segOffset;
1575 int libraryOrdinal;
1576 const char* symbolName;
1577 bool doneAfterBind;
1578 uintptr_t result;
1579 do {
1580 if ( ! getLazyBindingInfo(lazyBindingInfoOffset, start, end, &segIndex, &segOffset, &libraryOrdinal, &symbolName, &doneAfterBind) )
1581 dyld::throwf("bad lazy bind info");
1582
1583 if ( segIndex >= fSegmentsCount )
1584 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is too large (0..%d)",
1585 segIndex, fSegmentsCount-1);
1586 if ( segOffset > segSize(segIndex) )
1587 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has offset 0x%08lX beyond segment size (0x%08lX)", segOffset, segSize(segIndex));
1588 uintptr_t address = segActualLoadAddress(segIndex) + segOffset;
1589 result = bindAt(context, this, address, BIND_TYPE_POINTER, symbolName, 0, 0, libraryOrdinal,
1590 NULL, "lazy ", NULL, true);
1591 // <rdar://problem/24140465> Some old apps had multiple lazy symbols bound at once
1592 } while (!doneAfterBind && !context.strictMachORequired);
1593
1594 if ( !this->usesTwoLevelNameSpace() ) {
1595 // release dyld global lock
1596 if ( unlock != NULL )
1597 unlock();
1598 }
1599 return result;
1600 }
1601
1602 void ImageLoaderMachOCompressed::initializeCoalIterator(CoalIterator& it, unsigned int loadOrder, unsigned)
1603 {
1604 it.image = this;
1605 it.symbolName = " ";
1606 it.loadOrder = loadOrder;
1607 it.weakSymbol = false;
1608 it.symbolMatches = false;
1609 it.done = false;
1610 it.curIndex = 0;
1611 it.endIndex = (this->fDyldInfo ? this->fDyldInfo->weak_bind_size : 0);
1612 it.address = 0;
1613 it.type = 0;
1614 it.addend = 0;
1615 }
1616
1617
1618 bool ImageLoaderMachOCompressed::incrementCoalIterator(CoalIterator& it)
1619 {
1620 if ( it.done )
1621 return false;
1622
1623 if ( (this->fDyldInfo == nullptr) || (this->fDyldInfo->weak_bind_size == 0) ) {
1624 /// hmmm, ld set MH_WEAK_DEFINES or MH_BINDS_TO_WEAK, but there is no weak binding info
1625 it.done = true;
1626 it.symbolName = "~~~";
1627 return true;
1628 }
1629 const uint8_t* start = fLinkEditBase + fDyldInfo->weak_bind_off;
1630 const uint8_t* p = start + it.curIndex;
1631 const uint8_t* end = fLinkEditBase + fDyldInfo->weak_bind_off + this->fDyldInfo->weak_bind_size;
1632 uintptr_t count;
1633 uintptr_t skip;
1634 uintptr_t segOffset;
1635 while ( p < end ) {
1636 uint8_t immediate = *p & BIND_IMMEDIATE_MASK;
1637 uint8_t opcode = *p & BIND_OPCODE_MASK;
1638 ++p;
1639 switch (opcode) {
1640 case BIND_OPCODE_DONE:
1641 it.done = true;
1642 it.curIndex = p - start;
1643 it.symbolName = "~~~"; // sorts to end
1644 return true;
1645 case BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
1646 it.symbolName = (char*)p;
1647 it.weakSymbol = ((immediate & BIND_SYMBOL_FLAGS_NON_WEAK_DEFINITION) == 0);
1648 it.symbolMatches = false;
1649 while (*p != '\0')
1650 ++p;
1651 ++p;
1652 it.curIndex = p - start;
1653 return false;
1654 case BIND_OPCODE_SET_TYPE_IMM:
1655 it.type = immediate;
1656 break;
1657 case BIND_OPCODE_SET_ADDEND_SLEB:
1658 it.addend = read_sleb128(p, end);
1659 break;
1660 case BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
1661 if ( immediate >= fSegmentsCount )
1662 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is too large (0..%d)",
1663 immediate, fSegmentsCount-1);
1664 #if __arm__
1665 // <rdar://problem/23138428> iOS app compatibility
1666 if ( !segWriteable(immediate) && it.image->isPositionIndependentExecutable() )
1667 #elif TEXT_RELOC_SUPPORT
1668 // <rdar://problem/23479396&23590867> i386 OS X app compatibility
1669 if ( !segWriteable(immediate) && !segHasRebaseFixUps(immediate) && !segHasBindFixUps(immediate)
1670 && (!it.image->isExecutable() || it.image->isPositionIndependentExecutable()) )
1671 #else
1672 if ( !segWriteable(immediate) )
1673 #endif
1674 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB targets segment %s which is not writable", segName(immediate));
1675 segOffset = read_uleb128(p, end);
1676 if ( segOffset > segSize(immediate) )
1677 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has offset 0x%08lX beyond segment size (0x%08lX)", segOffset, segSize(immediate));
1678 it.address = segActualLoadAddress(immediate) + segOffset;
1679 break;
1680 case BIND_OPCODE_ADD_ADDR_ULEB:
1681 it.address += read_uleb128(p, end);
1682 break;
1683 case BIND_OPCODE_DO_BIND:
1684 it.address += sizeof(intptr_t);
1685 break;
1686 case BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB:
1687 it.address += read_uleb128(p, end) + sizeof(intptr_t);
1688 break;
1689 case BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED:
1690 it.address += immediate*sizeof(intptr_t) + sizeof(intptr_t);
1691 break;
1692 case BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB:
1693 count = read_uleb128(p, end);
1694 skip = read_uleb128(p, end);
1695 for (uint32_t i=0; i < count; ++i) {
1696 it.address += skip + sizeof(intptr_t);
1697 }
1698 break;
1699 default:
1700 dyld::throwf("bad weak bind opcode '%d' found after processing %d bytes in '%s'", *p, (int)(p-start), this->getPath());
1701 }
1702 }
1703 /// hmmm, BIND_OPCODE_DONE is missing...
1704 it.done = true;
1705 it.symbolName = "~~~";
1706 //dyld::log("missing BIND_OPCODE_DONE for image %s\n", this->getPath());
1707 return true;
1708 }
1709
1710 uintptr_t ImageLoaderMachOCompressed::getAddressCoalIterator(CoalIterator& it, const LinkContext& context)
1711 {
1712 //dyld::log("looking for %s in %s\n", it.symbolName, this->getPath());
1713 const ImageLoader* foundIn = NULL;
1714 const ImageLoader::Symbol* sym = this->findShallowExportedSymbol(it.symbolName, &foundIn);
1715 if ( sym != NULL ) {
1716 //dyld::log("sym=%p, foundIn=%p\n", sym, foundIn);
1717 return foundIn->getExportedSymbolAddress(sym, context, this);
1718 }
1719 return 0;
1720 }
1721
1722
1723 void ImageLoaderMachOCompressed::updateUsesCoalIterator(CoalIterator& it, uintptr_t value, ImageLoader* targetImage, unsigned targetIndex, const LinkContext& context)
1724 {
1725 // <rdar://problem/6570879> weak binding done too early with inserted libraries
1726 if ( this->getState() < dyld_image_state_bound )
1727 return;
1728
1729 if ( fDyldInfo == nullptr )
1730 return;
1731
1732 const uint8_t* start = fLinkEditBase + fDyldInfo->weak_bind_off;
1733 const uint8_t* p = start + it.curIndex;
1734 const uint8_t* end = fLinkEditBase + fDyldInfo->weak_bind_off + this->fDyldInfo->weak_bind_size;
1735
1736 uint8_t type = it.type;
1737 uintptr_t address = it.address;
1738 const char* symbolName = it.symbolName;
1739 intptr_t addend = it.addend;
1740 uintptr_t count;
1741 uintptr_t skip;
1742 uintptr_t segOffset;
1743 bool done = false;
1744 bool boundSomething = false;
1745 while ( !done && (p < end) ) {
1746 uint8_t immediate = *p & BIND_IMMEDIATE_MASK;
1747 uint8_t opcode = *p & BIND_OPCODE_MASK;
1748 ++p;
1749 switch (opcode) {
1750 case BIND_OPCODE_DONE:
1751 done = true;
1752 break;
1753 case BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
1754 done = true;
1755 break;
1756 case BIND_OPCODE_SET_TYPE_IMM:
1757 type = immediate;
1758 break;
1759 case BIND_OPCODE_SET_ADDEND_SLEB:
1760 addend = read_sleb128(p, end);
1761 break;
1762 case BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
1763 if ( immediate >= fSegmentsCount )
1764 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is too large (0..%d)",
1765 immediate, fSegmentsCount-1);
1766 #if __arm__
1767 // <rdar://problem/23138428> iOS app compatibility
1768 if ( !segWriteable(immediate) && it.image->isPositionIndependentExecutable() )
1769 #elif TEXT_RELOC_SUPPORT
1770 // <rdar://problem/23479396&23590867> i386 OS X app compatibility
1771 if ( !segWriteable(immediate) && !segHasRebaseFixUps(immediate) && !segHasBindFixUps(immediate)
1772 && (!it.image->isExecutable() || it.image->isPositionIndependentExecutable()) )
1773 #else
1774 if ( !segWriteable(immediate) )
1775 #endif
1776 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB targets segment %s which is not writable", segName(immediate));
1777 segOffset = read_uleb128(p, end);
1778 if ( segOffset > segSize(immediate) )
1779 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has offset 0x%08lX beyond segment size (0x%08lX)", segOffset, segSize(immediate));
1780 address = segActualLoadAddress(immediate) + segOffset;
1781 break;
1782 case BIND_OPCODE_ADD_ADDR_ULEB:
1783 address += read_uleb128(p, end);
1784 break;
1785 case BIND_OPCODE_DO_BIND:
1786 bindLocation(context, this->imageBaseAddress(), address, value, type, symbolName, addend, this->getPath(), targetImage ? targetImage->getPath() : NULL, "weak ", NULL, fSlide);
1787 boundSomething = true;
1788 address += sizeof(intptr_t);
1789 break;
1790 case BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB:
1791 bindLocation(context, this->imageBaseAddress(), address, value, type, symbolName, addend, this->getPath(), targetImage ? targetImage->getPath() : NULL, "weak ", NULL, fSlide);
1792 boundSomething = true;
1793 address += read_uleb128(p, end) + sizeof(intptr_t);
1794 break;
1795 case BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED:
1796 bindLocation(context, this->imageBaseAddress(), address, value, type, symbolName, addend, this->getPath(), targetImage ? targetImage->getPath() : NULL, "weak ", NULL, fSlide);
1797 boundSomething = true;
1798 address += immediate*sizeof(intptr_t) + sizeof(intptr_t);
1799 break;
1800 case BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB:
1801 count = read_uleb128(p, end);
1802 skip = read_uleb128(p, end);
1803 for (uint32_t i=0; i < count; ++i) {
1804 bindLocation(context, this->imageBaseAddress(), address, value, type, symbolName, addend, this->getPath(), targetImage ? targetImage->getPath() : NULL, "weak ", NULL, fSlide);
1805 boundSomething = true;
1806 address += skip + sizeof(intptr_t);
1807 }
1808 break;
1809 default:
1810 dyld::throwf("bad bind opcode %d in weak binding info", *p);
1811 }
1812 }
1813 // C++ weak coalescing cannot be tracked by reference counting. Error on side of never unloading.
1814 if ( boundSomething && (targetImage != this) )
1815 context.addDynamicReference(this, targetImage);
1816 }
1817
1818 uintptr_t ImageLoaderMachOCompressed::interposeAt(const LinkContext& context, ImageLoaderMachOCompressed* image,
1819 uintptr_t addr, uint8_t type, const char*,
1820 uint8_t, intptr_t, long,
1821 ExtraBindData *extraBindData,
1822 const char*, LastLookup*, bool runResolver)
1823 {
1824 if ( type == BIND_TYPE_POINTER ) {
1825 uintptr_t* fixupLocation = (uintptr_t*)addr;
1826 uintptr_t curValue = *fixupLocation;
1827 uintptr_t newValue = interposedAddress(context, curValue, image);
1828 if ( newValue != curValue) {
1829 *fixupLocation = newValue;
1830 }
1831 }
1832 return 0;
1833 }
1834
1835 void ImageLoaderMachOCompressed::doInterpose(const LinkContext& context)
1836 {
1837 if ( context.verboseInterposing )
1838 dyld::log("dyld: interposing %lu tuples onto image: %s\n", fgInterposingTuples.size(), this->getPath());
1839
1840 const dyld3::MachOAnalyzer* ma = (dyld3::MachOAnalyzer*)fMachOData;
1841 if ( !ma->hasChainedFixups() ) {
1842 // Note: all binds that happen as part of normal loading and fixups will have interposing applied.
1843 // There is only two cases where we need to parse bind opcodes and apply interposing:
1844
1845 // 1) Lazy pointers are either not bound yet, or in dyld cache they are prebound (to uninterposed target)
1846 eachLazyBind(context, ^(const LinkContext& ctx, ImageLoaderMachOCompressed* image,
1847 uintptr_t addr, uint8_t type, const char* symbolName,
1848 uint8_t symbolFlags, intptr_t addend, long libraryOrdinal,
1849 ExtraBindData *extraBindData,
1850 const char* msg, LastLookup* last, bool runResolver) {
1851 return ImageLoaderMachOCompressed::interposeAt(ctx, image, addr, type, symbolName, symbolFlags,
1852 addend, libraryOrdinal, extraBindData,
1853 msg, last, runResolver);
1854 });
1855
1856 // 2) non-lazy pointers in the dyld cache need to be interposed
1857 if ( ma->inDyldCache() ) {
1858 eachBind(context, ^(const LinkContext& ctx, ImageLoaderMachOCompressed* image,
1859 uintptr_t addr, uint8_t type, const char* symbolName,
1860 uint8_t symbolFlags, intptr_t addend, long libraryOrdinal,
1861 ExtraBindData *extraBindData,
1862 const char* msg, LastLookup* last, bool runResolver) {
1863 return ImageLoaderMachOCompressed::interposeAt(ctx, image, addr, type, symbolName, symbolFlags,
1864 addend, libraryOrdinal, extraBindData,
1865 msg, last, runResolver);
1866 });
1867 }
1868
1869 }
1870 }
1871
1872
1873 uintptr_t ImageLoaderMachOCompressed::dynamicInterposeAt(const LinkContext& context, ImageLoaderMachOCompressed* image,
1874 uintptr_t addr, uint8_t type, const char* symbolName,
1875 uint8_t, intptr_t, long,
1876 ExtraBindData *extraBindData,
1877 const char*, LastLookup*, bool runResolver)
1878 {
1879 if ( type == BIND_TYPE_POINTER ) {
1880 uintptr_t* fixupLocation = (uintptr_t*)addr;
1881 uintptr_t value = *fixupLocation;
1882 // don't apply interposing to table entries.
1883 if ( (context.dynamicInterposeArray <= (void*)addr) && ((void*)addr < &context.dynamicInterposeArray[context.dynamicInterposeCount]) )
1884 return 0;
1885 for(size_t i=0; i < context.dynamicInterposeCount; ++i) {
1886 if ( value == (uintptr_t)context.dynamicInterposeArray[i].replacee ) {
1887 if ( context.verboseInterposing ) {
1888 dyld::log("dyld: dynamic interposing: at %p replace %p with %p in %s\n",
1889 fixupLocation, context.dynamicInterposeArray[i].replacee, context.dynamicInterposeArray[i].replacement, image->getPath());
1890 }
1891 *fixupLocation = (uintptr_t)context.dynamicInterposeArray[i].replacement;
1892 }
1893 }
1894 }
1895 return 0;
1896 }
1897
1898 void ImageLoaderMachOCompressed::dynamicInterpose(const LinkContext& context)
1899 {
1900 if ( context.verboseInterposing )
1901 dyld::log("dyld: dynamic interposing %lu tuples onto image: %s\n", context.dynamicInterposeCount, this->getPath());
1902
1903 // update already bound references to symbols
1904 eachBind(context, ^(const LinkContext& ctx, ImageLoaderMachOCompressed* image,
1905 uintptr_t addr, uint8_t type, const char* symbolName,
1906 uint8_t symbolFlags, intptr_t addend, long libraryOrdinal,
1907 ExtraBindData *extraBindData,
1908 const char* msg, LastLookup* last, bool runResolver) {
1909 return ImageLoaderMachOCompressed::dynamicInterposeAt(ctx, image, addr, type, symbolName, symbolFlags,
1910 addend, libraryOrdinal, extraBindData,
1911 msg, last, runResolver);
1912 });
1913 eachLazyBind(context, ^(const LinkContext& ctx, ImageLoaderMachOCompressed* image,
1914 uintptr_t addr, uint8_t type, const char* symbolName,
1915 uint8_t symbolFlags, intptr_t addend, long libraryOrdinal,
1916 ExtraBindData *extraBindData,
1917 const char* msg, LastLookup* last, bool runResolver) {
1918 return ImageLoaderMachOCompressed::dynamicInterposeAt(ctx, image, addr, type, symbolName, symbolFlags,
1919 addend, libraryOrdinal, extraBindData,
1920 msg, last, runResolver);
1921 });
1922 }
1923
1924 const char* ImageLoaderMachOCompressed::findClosestSymbol(const void* addr, const void** closestAddr) const
1925 {
1926 return ImageLoaderMachO::findClosestSymbol((mach_header*)fMachOData, addr, closestAddr);
1927 }
1928
1929
1930 #if PREBOUND_IMAGE_SUPPORT
1931 void ImageLoaderMachOCompressed::resetPreboundLazyPointers(const LinkContext& context)
1932 {
1933 // no way to back off a prebound compress image
1934 }
1935 #endif
1936
1937
1938 #if __arm__ || __x86_64__
1939 void ImageLoaderMachOCompressed::updateAlternateLazyPointer(uint8_t* stub, void** originalLazyPointerAddr, const LinkContext& context)
1940 {
1941 #if __arm__
1942 uint32_t* instructions = (uint32_t*)stub;
1943 // sanity check this is a stub we understand
1944 if ( (instructions[0] != 0xe59fc004) || (instructions[1] != 0xe08fc00c) || (instructions[2] != 0xe59cf000) )
1945 return;
1946
1947 void** lazyPointerAddr = (void**)(instructions[3] + (stub + 12));
1948 #endif
1949 #if __x86_64__
1950 // sanity check this is a stub we understand
1951 if ( (stub[0] != 0xFF) || (stub[1] != 0x25) )
1952 return;
1953 int32_t ripOffset = *((int32_t*)(&stub[2]));
1954 void** lazyPointerAddr = (void**)(ripOffset + stub + 6);
1955 #endif
1956
1957 // if stub does not use original lazy pointer (meaning it was optimized by update_dyld_shared_cache)
1958 if ( lazyPointerAddr != originalLazyPointerAddr ) {
1959 // <rdar://problem/12928448> only de-optimization lazy pointers if they are part of shared cache not loaded (because overridden)
1960 const ImageLoader* lazyPointerImage = context.findImageContainingAddress(lazyPointerAddr);
1961 if ( lazyPointerImage != NULL )
1962 return;
1963
1964 // copy newly re-bound lazy pointer value to shared lazy pointer
1965 *lazyPointerAddr = *originalLazyPointerAddr;
1966
1967 if ( context.verboseBind )
1968 dyld::log("dyld: alter bind: %s: *0x%08lX = 0x%08lX \n",
1969 this->getShortName(), (long)lazyPointerAddr, (long)*originalLazyPointerAddr);
1970 }
1971 }
1972 #endif
1973
1974
1975 // <rdar://problem/8890875> overriding shared cache dylibs with resolvers fails
1976 void ImageLoaderMachOCompressed::updateOptimizedLazyPointers(const LinkContext& context)
1977 {
1978 #if __arm__ || __x86_64__
1979 // find stubs and indirect symbol table
1980 const struct macho_section* stubsSection = NULL;
1981 const dysymtab_command* dynSymbolTable = NULL;
1982 const macho_header* mh = (macho_header*)fMachOData;
1983 const uint32_t cmd_count = mh->ncmds;
1984 const struct load_command* const cmds = (struct load_command*)&fMachOData[sizeof(macho_header)];
1985 const struct load_command* cmd = cmds;
1986 for (uint32_t i = 0; i < cmd_count; ++i) {
1987 if (cmd->cmd == LC_SEGMENT_COMMAND) {
1988 const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
1989 const struct macho_section* const sectionsStart = (struct macho_section*)((char*)seg + sizeof(struct macho_segment_command));
1990 const struct macho_section* const sectionsEnd = &sectionsStart[seg->nsects];
1991 for (const struct macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
1992 const uint8_t type = sect->flags & SECTION_TYPE;
1993 if ( type == S_SYMBOL_STUBS )
1994 stubsSection = sect;
1995 }
1996 }
1997 else if ( cmd->cmd == LC_DYSYMTAB ) {
1998 dynSymbolTable = (struct dysymtab_command*)cmd;
1999 }
2000 cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
2001 }
2002 if ( dynSymbolTable == NULL )
2003 return;
2004 const uint32_t* const indirectTable = (uint32_t*)&fLinkEditBase[dynSymbolTable->indirectsymoff];
2005 if ( stubsSection == NULL )
2006 return;
2007 const uint32_t stubsSize = stubsSection->reserved2;
2008 const uint32_t stubsCount = (uint32_t)(stubsSection->size / stubsSize);
2009 const uint32_t stubsIndirectTableOffset = stubsSection->reserved1;
2010 if ( (stubsIndirectTableOffset+stubsCount) > dynSymbolTable->nindirectsyms )
2011 return;
2012 uint8_t* const stubsAddr = (uint8_t*)(stubsSection->addr + this->fSlide);
2013
2014 // for each lazy pointer section
2015 cmd = cmds;
2016 for (uint32_t i = 0; i < cmd_count; ++i) {
2017 if (cmd->cmd == LC_SEGMENT_COMMAND) {
2018 const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
2019 const struct macho_section* const sectionsStart = (struct macho_section*)((char*)seg + sizeof(struct macho_segment_command));
2020 const struct macho_section* const sectionsEnd = &sectionsStart[seg->nsects];
2021 for (const struct macho_section* lazyPointerSection=sectionsStart; lazyPointerSection < sectionsEnd; ++lazyPointerSection) {
2022 const uint8_t type = lazyPointerSection->flags & SECTION_TYPE;
2023 if ( type != S_LAZY_SYMBOL_POINTERS )
2024 continue;
2025 const uint32_t lazyPointersCount = (uint32_t)(lazyPointerSection->size / sizeof(void*));
2026 const uint32_t lazyPointersIndirectTableOffset = lazyPointerSection->reserved1;
2027 if ( (lazyPointersIndirectTableOffset+lazyPointersCount) > dynSymbolTable->nindirectsyms )
2028 continue;
2029 void** const lazyPointersAddr = (void**)(lazyPointerSection->addr + this->fSlide);
2030 // for each lazy pointer
2031 for(uint32_t lpIndex=0; lpIndex < lazyPointersCount; ++lpIndex) {
2032 const uint32_t lpSymbolIndex = indirectTable[lazyPointersIndirectTableOffset+lpIndex];
2033 // find matching stub and validate it uses this lazy pointer
2034 for(uint32_t stubIndex=0; stubIndex < stubsCount; ++stubIndex) {
2035 if ( indirectTable[stubsIndirectTableOffset+stubIndex] == lpSymbolIndex ) {
2036 this->updateAlternateLazyPointer(stubsAddr+stubIndex*stubsSize, &lazyPointersAddr[lpIndex], context);
2037 break;
2038 }
2039 }
2040 }
2041
2042 }
2043 }
2044 cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
2045 }
2046
2047 #endif
2048 }
2049
2050
2051 void ImageLoaderMachOCompressed::registerEncryption(const encryption_info_command* encryptCmd, const LinkContext& context)
2052 {
2053 #if __arm__ || __arm64__
2054 if ( encryptCmd == NULL )
2055 return;
2056 // fMachOData not set up yet, need to manually find mach_header
2057 const mach_header* mh = NULL;
2058 for(unsigned int i=0; i < fSegmentsCount; ++i) {
2059 if ( (segFileOffset(i) == 0) && (segFileSize(i) != 0) ) {
2060 mh = (mach_header*)segActualLoadAddress(i);
2061 void* start = ((uint8_t*)mh) + encryptCmd->cryptoff;
2062 size_t len = encryptCmd->cryptsize;
2063 uint32_t cputype = mh->cputype;
2064 uint32_t cpusubtype = mh->cpusubtype;
2065 uint32_t cryptid = encryptCmd->cryptid;
2066 if (context.verboseMapping) {
2067 dyld::log(" 0x%08lX->0x%08lX configured for FairPlay decryption\n", (long)start, (long)start+len);
2068 }
2069 int result = mremap_encrypted(start, len, cryptid, cputype, cpusubtype);
2070 if ( result != 0 ) {
2071 dyld::throwf("mremap_encrypted() => %d, errno=%d for %s\n", result, errno, this->getPath());
2072 }
2073 return;
2074 }
2075 }
2076 #endif
2077 }
2078
2079
2080
mirror of dyld