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dyld-832.7.1.tar.gz
[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 TARGET_OS_OSX
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 // upward 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 TARGET_OS_OSX
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, weak_import, 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 // Try get the path from the load commands
829 if ( const char* depPath = libPath((unsigned int)libraryOrdinal-1) ) {
830 dyld::throwf("can't resolve symbol %s in %s because dependent dylib %s could not be loaded",
831 symbolName, this->getPath(), depPath);
832 } else {
833 dyld::throwf("can't resolve symbol %s in %s because dependent dylib #%ld could not be loaded",
834 symbolName, this->getPath(), libraryOrdinal);
835 }
836 }
837 }
838 else {
839 symbolAddress = resolveTwolevel(context, symbolName, *targetImage, this, (unsigned)libraryOrdinal, weak_import, runResolver, targetImage);
840 }
841 }
842
843 // save off lookup results if client wants
844 if ( last != NULL ) {
845 last->ordinal = libraryOrdinal;
846 last->flags = symboFlags;
847 last->name = symbolName;
848 last->foundIn = *targetImage;
849 last->result = symbolAddress;
850 }
851
852 return symbolAddress;
853 }
854
855 uintptr_t ImageLoaderMachOCompressed::bindAt(const LinkContext& context, ImageLoaderMachOCompressed* image,
856 uintptr_t addr, uint8_t type, const char* symbolName,
857 uint8_t symbolFlags, intptr_t addend, long libraryOrdinal,
858 ExtraBindData *extraBindData,
859 const char* msg, LastLookup* last, bool runResolver)
860 {
861 const ImageLoader* targetImage;
862 uintptr_t symbolAddress;
863
864 // resolve symbol
865 if (type == BIND_TYPE_THREADED_REBASE) {
866 symbolAddress = 0;
867 targetImage = nullptr;
868 } else
869 symbolAddress = image->resolve(context, symbolName, symbolFlags, libraryOrdinal, &targetImage, last, runResolver);
870
871 // do actual update
872 return image->bindLocation(context, image->imageBaseAddress(), addr, symbolAddress, type, symbolName, addend, image->getPath(), targetImage ? targetImage->getPath() : NULL, msg, extraBindData, image->fSlide);
873 }
874
875
876 void ImageLoaderMachOCompressed::throwBadBindingAddress(uintptr_t address, uintptr_t segmentEndAddress, int segmentIndex,
877 const uint8_t* startOpcodes, const uint8_t* endOpcodes, const uint8_t* pos)
878 {
879 dyld::throwf("malformed binding opcodes (%ld/%ld): address 0x%08lX is outside segment %s (0x%08lX -> 0x%08lX)",
880 (intptr_t)(pos-startOpcodes), (intptr_t)(endOpcodes-startOpcodes), address, segName(segmentIndex),
881 segActualLoadAddress(segmentIndex), segmentEndAddress);
882 }
883
884
885 void ImageLoaderMachOCompressed::doBind(const LinkContext& context, bool forceLazysBound, const ImageLoader* reExportParent)
886 {
887 CRSetCrashLogMessage2(this->getPath());
888
889 // if prebound and loaded at prebound address, and all libraries are same as when this was prebound, then no need to bind
890 // note: flat-namespace binaries need to have imports rebound (even if correctly prebound)
891 if ( this->usablePrebinding(context) ) {
892 // don't need to bind
893 // except weak which may now be inline with the regular binds
894 if ( this->participatesInCoalescing() && (fDyldInfo != nullptr) ) {
895 // run through all binding opcodes
896 eachBind(context, ^(const LinkContext& ctx, ImageLoaderMachOCompressed* image,
897 uintptr_t addr, uint8_t type, const char* symbolName,
898 uint8_t symbolFlags, intptr_t addend, long libraryOrdinal,
899 ExtraBindData *extraBindData,
900 const char* msg, LastLookup* last, bool runResolver) {
901 if ( libraryOrdinal != BIND_SPECIAL_DYLIB_WEAK_LOOKUP )
902 return (uintptr_t)0;
903 return ImageLoaderMachOCompressed::bindAt(ctx, image, addr, type, symbolName, symbolFlags,
904 addend, libraryOrdinal, extraBindData,
905 msg, last, runResolver);
906 });
907 }
908 }
909 else {
910 uint64_t t0 = mach_absolute_time();
911
912 uint32_t ignore;
913 bool bindingBecauseOfRoot = ( this->overridesCachedDylib(ignore) || this->inSharedCache() );
914 vmAccountingSetSuspended(context, bindingBecauseOfRoot);
915
916 if ( fChainedFixups != NULL ) {
917 const dyld_chained_fixups_header* fixupsHeader = (dyld_chained_fixups_header*)(fLinkEditBase + fChainedFixups->dataoff);
918 doApplyFixups(context, fixupsHeader);
919 }
920 else if ( fDyldInfo != nullptr ) {
921 #if TEXT_RELOC_SUPPORT
922 // if there are __TEXT fixups, temporarily make __TEXT writable
923 if ( fTextSegmentBinds )
924 this->makeTextSegmentWritable(context, true);
925 #endif
926
927 // run through all binding opcodes
928 eachBind(context, ^(const LinkContext& ctx, ImageLoaderMachOCompressed* image,
929 uintptr_t addr, uint8_t type, const char* symbolName,
930 uint8_t symbolFlags, intptr_t addend, long libraryOrdinal,
931 ExtraBindData *extraBindData,
932 const char* msg, LastLookup* last, bool runResolver) {
933 return ImageLoaderMachOCompressed::bindAt(ctx, image, addr, type, symbolName, symbolFlags,
934 addend, libraryOrdinal, extraBindData,
935 msg, last, runResolver);
936 });
937
938 #if TEXT_RELOC_SUPPORT
939 // if there were __TEXT fixups, restore write protection
940 if ( fTextSegmentBinds )
941 this->makeTextSegmentWritable(context, false);
942 #endif
943
944 // if this image is in the shared cache, but depends on something no longer in the shared cache,
945 // there is no way to reset the lazy pointers, so force bind them now
946 if ( forceLazysBound || fInSharedCache )
947 this->doBindJustLazies(context);
948
949 // this image is in cache, but something below it is not. If
950 // this image has lazy pointer to a resolver function, then
951 // the stub may have been altered to point to a shared lazy pointer.
952 if ( fInSharedCache )
953 this->updateOptimizedLazyPointers(context);
954 }
955
956 uint64_t t1 = mach_absolute_time();
957 ImageLoader::fgTotalRebindCacheTime += (t1-t0);
958 }
959
960 // See if this dylib overrides something in the dyld cache
961 uint32_t dyldCacheOverrideImageNum;
962 if ( context.dyldCache && context.dyldCache->header.builtFromChainedFixups && overridesCachedDylib(dyldCacheOverrideImageNum) ) {
963 // need to patch all other places in cache that point to the overridden dylib, to point to this dylib instead
964 const dyld3::closure::Image* overriddenImage = context.dyldCache->cachedDylibsImageArray()->imageForNum(dyldCacheOverrideImageNum);
965 uint32_t imageIndex = dyldCacheOverrideImageNum - (uint32_t)context.dyldCache->cachedDylibsImageArray()->startImageNum();
966 //dyld::log("doBind() found override of %s\n", this->getPath());
967 context.dyldCache->forEachPatchableExport(imageIndex, ^(uint32_t cacheOffsetOfImpl, const char* exportName) {
968 uintptr_t newImpl = 0;
969 const ImageLoader* foundIn = nullptr;
970 if ( this->findExportedSymbolAddress(context, exportName, NULL, 0, false, &foundIn, &newImpl) ) {
971 //dyld::log(" patchCacheUsesOf(%s) found in %s\n", exportName, foundIn->getPath());
972 patchCacheUsesOf(context, overriddenImage, cacheOffsetOfImpl, exportName, newImpl);
973 }
974 else {
975 // <rdar://problem/59196856> allow patched impls to move between re-export sibling dylibs
976 if ( reExportParent != nullptr ) {
977 reExportParent->forEachReExportDependent(^(const ImageLoader* reExportedDep, bool& stop) {
978 uintptr_t siblingImpl = 0;
979 const ImageLoader* foundInSibling = nullptr;
980 if ( reExportedDep->findExportedSymbolAddress(context, exportName, NULL, 0, false, &foundInSibling, &siblingImpl) ) {
981 stop = true;
982 //dyld::log(" patchCacheUsesOf(%s) found in sibling %s\n", exportName, foundInSibling->getPath());
983 patchCacheUsesOf(context, overriddenImage, cacheOffsetOfImpl, exportName, siblingImpl);
984 }
985 });
986 }
987 }
988 });
989 }
990
991 // set up dyld entry points in image
992 // do last so flat main executables will have __dyld or __program_vars set up
993 this->setupLazyPointerHandler(context);
994 CRSetCrashLogMessage2(NULL);
995 }
996
997
998 void ImageLoaderMachOCompressed::doBindJustLazies(const LinkContext& context)
999 {
1000 eachLazyBind(context, ^(const LinkContext& ctx, ImageLoaderMachOCompressed* image,
1001 uintptr_t addr, uint8_t type, const char* symbolName,
1002 uint8_t symbolFlags, intptr_t addend, long libraryOrdinal,
1003 ExtraBindData *extraBindData,
1004 const char* msg, LastLookup* last, bool runResolver) {
1005 return ImageLoaderMachOCompressed::bindAt(ctx, image, addr, type, symbolName, symbolFlags,
1006 addend, libraryOrdinal, extraBindData,
1007 msg, last, runResolver);
1008 });
1009 }
1010
1011 void ImageLoaderMachOCompressed::doApplyFixups(const LinkContext& context, const dyld_chained_fixups_header* fixupsHeader)
1012 {
1013 const dyld3::MachOLoaded* ml = (dyld3::MachOLoaded*)machHeader();
1014 const dyld_chained_starts_in_image* starts = (dyld_chained_starts_in_image*)((uint8_t*)fixupsHeader + fixupsHeader->starts_offset);
1015
1016 // build table of resolved targets for each symbol ordinal
1017 STACK_ALLOC_OVERFLOW_SAFE_ARRAY(const void*, targetAddrs, 128);
1018 targetAddrs.reserve(fixupsHeader->imports_count);
1019 __block Diagnostics diag;
1020 const dyld3::MachOAnalyzer* ma = (dyld3::MachOAnalyzer*)ml;
1021 ma->forEachChainedFixupTarget(diag, ^(int libOrdinal, const char* symbolName, uint64_t addend, bool weakImport, bool& stop) {
1022 const ImageLoader* targetImage;
1023 uint8_t symbolFlags = weakImport ? BIND_SYMBOL_FLAGS_WEAK_IMPORT : 0;
1024 try {
1025 uintptr_t symbolAddress = this->resolve(context, symbolName, symbolFlags, libOrdinal, &targetImage, NULL, true);
1026 targetAddrs.push_back((void*)(symbolAddress + addend));
1027 }
1028 catch (const char* msg) {
1029 stop = true;
1030 diag.error("%s", msg);
1031 }
1032 });
1033 if ( diag.hasError() )
1034 throw strdup(diag.errorMessage());
1035
1036 auto logFixups = ^(void* loc, void* newValue) {
1037 dyld::log("dyld: fixup: %s:%p = %p\n", this->getShortName(), loc, newValue);
1038 };
1039 if ( !context.verboseBind )
1040 logFixups = nullptr;
1041
1042 ml->fixupAllChainedFixups(diag, starts, fSlide, targetAddrs, logFixups);
1043 if ( diag.hasError() )
1044 throw strdup(diag.errorMessage());
1045 }
1046
1047 void ImageLoaderMachOCompressed::registerInterposing(const LinkContext& context)
1048 {
1049 // mach-o files advertise interposing by having a __DATA __interpose section
1050 struct InterposeData { uintptr_t replacement; uintptr_t replacee; };
1051
1052 __block Diagnostics diag;
1053 const dyld3::MachOAnalyzer* ma = (dyld3::MachOAnalyzer*)fMachOData;
1054 ma->forEachInterposingSection(diag, ^(uint64_t vmOffset, uint64_t vmSize, bool& stopSections) {
1055 if ( ma->hasChainedFixups() ) {
1056 const uint16_t pointerFormat = ma->chainedPointerFormat();
1057 const uint8_t* sectionStart = fMachOData+vmOffset;
1058 const uint8_t* sectionEnd = fMachOData+vmOffset+vmSize;
1059 ma->withChainStarts(diag, ma->chainStartsOffset(), ^(const dyld_chained_starts_in_image* startsInfo) {
1060 __block uintptr_t lastRebaseTarget = 0;
1061 ma->forEachFixupInAllChains(diag, startsInfo, false, ^(dyld3::MachOLoaded::ChainedFixupPointerOnDisk* fixupLoc, const dyld_chained_starts_in_segment* segInfo, bool& stopFixups) {
1062 if ( ((uint8_t*)fixupLoc < sectionStart) || ((uint8_t*)fixupLoc >= sectionEnd) )
1063 return;
1064 uint64_t rebaseTargetRuntimeOffset;
1065 uint32_t bindOrdinal;
1066 int64_t ptrAddend;
1067 if ( fixupLoc->isRebase(pointerFormat, 0, rebaseTargetRuntimeOffset) ) {
1068 //dyld::log("interpose rebase at fixup at %p to 0x%0llX\n", fixupLoc, rebaseTargetRuntimeOffset);
1069 lastRebaseTarget = (uintptr_t)(fMachOData+rebaseTargetRuntimeOffset);
1070 }
1071 else if ( fixupLoc->isBind(pointerFormat, bindOrdinal, ptrAddend) ) {
1072 //dyld::log("interpose bind fixup at %p to bind ordinal %d\n", fixupLoc, bindOrdinal);
1073 __block uint32_t targetBindIndex = 0;
1074 ma->forEachChainedFixupTarget(diag, ^(int libraryOrdinal, const char* symbolName, uint64_t addend, bool weakImport, bool& stop) {
1075 if ( targetBindIndex == bindOrdinal ) {
1076 //dyld::log("interpose bind fixup at %p is to %s libOrdinal=%d\n", fixupLoc, symbolName, libraryOrdinal);
1077 LastLookup* last = NULL;
1078 const ImageLoader* targetImage;
1079 uintptr_t targetBindAddress = 0;
1080 try {
1081 targetBindAddress = this->resolve(context, symbolName, 0, libraryOrdinal, &targetImage, last, false);
1082 }
1083 catch (const char* msg) {
1084 if ( !weakImport )
1085 throw msg;
1086 targetBindAddress = 0;
1087 }
1088 //dyld::log("interpose bind fixup at %p is bound to 0x%lX\n", fixupLoc, targetBindAddress);
1089 // <rdar://problem/25686570> ignore interposing on a weak function that does not exist
1090 if ( targetBindAddress == 0 )
1091 return;
1092 ImageLoader::InterposeTuple tuple;
1093 tuple.replacement = lastRebaseTarget;
1094 tuple.neverImage = this;
1095 tuple.onlyImage = NULL;
1096 tuple.replacee = targetBindAddress;
1097 // <rdar://problem/7937695> verify that replacement is in this image
1098 if ( this->containsAddress((void*)tuple.replacement) ) {
1099 if ( context.verboseInterposing )
1100 dyld::log("dyld: interposing 0x%lx with 0x%lx\n", tuple.replacee, tuple.replacement);
1101 // chain to any existing interpositions
1102 for (std::vector<InterposeTuple>::iterator it=fgInterposingTuples.begin(); it != fgInterposingTuples.end(); it++) {
1103 if ( it->replacee == tuple.replacee ) {
1104 tuple.replacee = it->replacement;
1105 }
1106 }
1107 ImageLoader::fgInterposingTuples.push_back(tuple);
1108 }
1109 }
1110 ++targetBindIndex;
1111 });
1112 }
1113 });
1114 });
1115 }
1116 else {
1117 // traditional (non-chained) fixups
1118 const size_t count = (size_t)(vmSize / sizeof(InterposeData));
1119 const InterposeData* interposeArray = (InterposeData*)(fMachOData+vmOffset);
1120 if ( context.verboseInterposing )
1121 dyld::log("dyld: found %lu interposing tuples in %s\n", count, getPath());
1122 for (size_t j=0; j < count; ++j) {
1123 uint64_t bindOffset = ((uint8_t*)&(interposeArray[j].replacee)) - fMachOData;
1124 ma->forEachBind(diag, ^(uint64_t runtimeOffset, int libOrdinal, const char* symbolName, bool weakImport, bool lazyBind, uint64_t addend, bool& stopBinds) {
1125 if ( bindOffset != runtimeOffset )
1126 return;
1127 stopBinds = true;
1128 LastLookup* last = NULL;
1129 const ImageLoader* targetImage;
1130 uintptr_t targetBindAddress = 0;
1131 try {
1132 targetBindAddress = this->resolve(context, symbolName, 0, libOrdinal, &targetImage, last, false);
1133 }
1134 catch (const char* msg) {
1135 if ( !weakImport )
1136 throw msg;
1137 targetBindAddress = 0;
1138 }
1139 ImageLoader::InterposeTuple tuple;
1140 tuple.replacement = interposeArray[j].replacement;
1141 tuple.neverImage = this;
1142 tuple.onlyImage = NULL;
1143 tuple.replacee = targetBindAddress;
1144 // <rdar://problem/25686570> ignore interposing on a weak function that does not exist
1145 if ( tuple.replacee == 0 )
1146 return;
1147 // <rdar://problem/7937695> verify that replacement is in this image
1148 if ( this->containsAddress((void*)tuple.replacement) ) {
1149 if ( context.verboseInterposing )
1150 dyld::log("dyld: interposing 0x%lx with 0x%lx\n", tuple.replacee, tuple.replacement);
1151 // chain to any existing interpositions
1152 for (std::vector<InterposeTuple>::iterator it=fgInterposingTuples.begin(); it != fgInterposingTuples.end(); it++) {
1153 if ( it->replacee == tuple.replacee ) {
1154 tuple.replacee = it->replacement;
1155 }
1156 }
1157 ImageLoader::fgInterposingTuples.push_back(tuple);
1158 }
1159 }, ^(const char* symbolName){
1160 });
1161 }
1162 }
1163 });
1164 }
1165
1166 bool ImageLoaderMachOCompressed::usesChainedFixups() const
1167 {
1168 return ((dyld3::MachOLoaded*)machHeader())->hasChainedFixups();
1169 }
1170
1171 struct ThreadedBindData {
1172 ThreadedBindData(const char* symbolName, int64_t addend, long libraryOrdinal, uint8_t symbolFlags, uint8_t type)
1173 : symbolName(symbolName), addend(addend), libraryOrdinal(libraryOrdinal), symbolFlags(symbolFlags), type(type) { }
1174
1175 std::tuple<const char*, int64_t, long, bool, uint8_t> pack() const {
1176 return std::make_tuple(symbolName, addend, libraryOrdinal, symbolFlags, type);
1177 }
1178
1179 const char* symbolName = nullptr;
1180 int64_t addend = 0;
1181 long libraryOrdinal = 0;
1182 uint8_t symbolFlags = 0;
1183 uint8_t type = 0;
1184 };
1185
1186 void ImageLoaderMachOCompressed::makeDataReadOnly() const
1187 {
1188 #if !TEXT_RELOC_SUPPORT
1189 if ( fReadOnlyDataSegment && !this->ImageLoader::inSharedCache() ) {
1190 for (unsigned int i=0; i < fSegmentsCount; ++i) {
1191 if ( segIsReadOnlyData(i) ) {
1192 uintptr_t start = segActualLoadAddress(i);
1193 uintptr_t size = segSize(i);
1194 #if defined(__x86_64__) && !TARGET_OS_SIMULATOR
1195 if ( dyld::isTranslated() ) {
1196 // <rdar://problem/48325338> can't mprotect non-16KB segments
1197 if ( ((size & 0x3FFF) != 0) || ((start & 0x3FFF) != 0) )
1198 continue;
1199 }
1200 #endif
1201 ::mprotect((void*)start, size, PROT_READ);
1202 //dyld::log("make read-only 0x%09lX -> 0x%09lX\n", (long)start, (long)(start+size));
1203 }
1204 }
1205 }
1206 #endif
1207 }
1208
1209
1210 void ImageLoaderMachOCompressed::eachBind(const LinkContext& context, bind_handler handler)
1211 {
1212 try {
1213 uint8_t type = 0;
1214 int segmentIndex = -1;
1215 uintptr_t address = segActualLoadAddress(0);
1216 uintptr_t segmentStartAddress = segActualLoadAddress(0);
1217 uintptr_t segmentEndAddress = segActualEndAddress(0);
1218 const char* symbolName = NULL;
1219 uint8_t symboFlags = 0;
1220 bool libraryOrdinalSet = false;
1221 long libraryOrdinal = 0;
1222 intptr_t addend = 0;
1223 uintptr_t count;
1224 uintptr_t skip;
1225 uintptr_t segOffset = 0;
1226
1227 dyld3::OverflowSafeArray<ThreadedBindData> ordinalTable;
1228 bool useThreadedRebaseBind = false;
1229 ExtraBindData extraBindData;
1230 LastLookup last = { 0, 0, NULL, 0, NULL };
1231 const uint8_t* const start = fLinkEditBase + fDyldInfo->bind_off;
1232 const uint8_t* const end = &start[fDyldInfo->bind_size];
1233 const uint8_t* p = start;
1234 bool done = false;
1235 while ( !done && (p < end) ) {
1236 uint8_t immediate = *p & BIND_IMMEDIATE_MASK;
1237 uint8_t opcode = *p & BIND_OPCODE_MASK;
1238 ++p;
1239 switch (opcode) {
1240 case BIND_OPCODE_DONE:
1241 done = true;
1242 break;
1243 case BIND_OPCODE_SET_DYLIB_ORDINAL_IMM:
1244 libraryOrdinal = immediate;
1245 libraryOrdinalSet = true;
1246 break;
1247 case BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB:
1248 libraryOrdinal = read_uleb128(p, end);
1249 libraryOrdinalSet = true;
1250 break;
1251 case BIND_OPCODE_SET_DYLIB_SPECIAL_IMM:
1252 // the special ordinals are negative numbers
1253 if ( immediate == 0 )
1254 libraryOrdinal = 0;
1255 else {
1256 int8_t signExtended = BIND_OPCODE_MASK | immediate;
1257 libraryOrdinal = signExtended;
1258 }
1259 libraryOrdinalSet = true;
1260 break;
1261 case BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
1262 symbolName = (char*)p;
1263 symboFlags = immediate;
1264 while (*p != '\0')
1265 ++p;
1266 ++p;
1267 break;
1268 case BIND_OPCODE_SET_TYPE_IMM:
1269 type = immediate;
1270 break;
1271 case BIND_OPCODE_SET_ADDEND_SLEB:
1272 addend = read_sleb128(p, end);
1273 break;
1274 case BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
1275 segmentIndex = immediate;
1276 if ( (segmentIndex >= fSegmentsCount) || (segmentIndex < 0) )
1277 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is out of range (0..%d)",
1278 segmentIndex, fSegmentsCount-1);
1279 #if TEXT_RELOC_SUPPORT
1280 if ( !segWriteable(segmentIndex) && !segHasRebaseFixUps(segmentIndex) && !segHasBindFixUps(segmentIndex) )
1281 #else
1282 if ( !segWriteable(segmentIndex) )
1283 #endif
1284 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is not writable", segmentIndex);
1285 segOffset = read_uleb128(p, end);
1286 if ( segOffset > segSize(segmentIndex) )
1287 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has offset 0x%08lX beyond segment size (0x%08lX)", segOffset, segSize(segmentIndex));
1288 segmentStartAddress = segActualLoadAddress(segmentIndex);
1289 address = segmentStartAddress + segOffset;
1290 segmentEndAddress = segActualEndAddress(segmentIndex);
1291 break;
1292 case BIND_OPCODE_ADD_ADDR_ULEB:
1293 address += read_uleb128(p, end);
1294 break;
1295 case BIND_OPCODE_DO_BIND:
1296 if (!useThreadedRebaseBind) {
1297 if ( (address < segmentStartAddress) || (address >= segmentEndAddress) )
1298 throwBadBindingAddress(address, segmentEndAddress, segmentIndex, start, end, p);
1299 if ( symbolName == NULL )
1300 dyld::throwf("BIND_OPCODE_DO_BIND missing preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM");
1301 if ( segmentIndex == -1 )
1302 dyld::throwf("BIND_OPCODE_DO_BIND missing preceding BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB");
1303 if ( !libraryOrdinalSet )
1304 dyld::throwf("BIND_OPCODE_DO_BIND missing preceding BIND_OPCODE_SET_DYLIB_ORDINAL*");
1305 handler(context, this, address, type, symbolName, symboFlags, addend, libraryOrdinal,
1306 &extraBindData, "", &last, false);
1307 address += sizeof(intptr_t);
1308 } else {
1309 ordinalTable.push_back(ThreadedBindData(symbolName, addend, libraryOrdinal, symboFlags, type));
1310 }
1311 break;
1312 case BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB:
1313 if ( (address < segmentStartAddress) || (address >= segmentEndAddress) )
1314 throwBadBindingAddress(address, segmentEndAddress, segmentIndex, start, end, p);
1315 if ( symbolName == NULL )
1316 dyld::throwf("BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB missing preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM");
1317 if ( segmentIndex == -1 )
1318 dyld::throwf("BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB missing preceding BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB");
1319 if ( !libraryOrdinalSet )
1320 dyld::throwf("BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB missing preceding BIND_OPCODE_SET_DYLIB_ORDINAL*");
1321 handler(context, this, address, type, symbolName, symboFlags, addend, libraryOrdinal,
1322 &extraBindData, "", &last, false);
1323 address += read_uleb128(p, end) + sizeof(intptr_t);
1324 break;
1325 case BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED:
1326 if ( (address < segmentStartAddress) || (address >= segmentEndAddress) )
1327 throwBadBindingAddress(address, segmentEndAddress, segmentIndex, start, end, p);
1328 if ( symbolName == NULL )
1329 dyld::throwf("BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED missing preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM");
1330 if ( segmentIndex == -1 )
1331 dyld::throwf("BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED missing preceding BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB");
1332 if ( !libraryOrdinalSet )
1333 dyld::throwf("BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED missing preceding BIND_OPCODE_SET_DYLIB_ORDINAL*");
1334 handler(context, this, address, type, symbolName, symboFlags, addend, libraryOrdinal,
1335 &extraBindData, "", &last, false);
1336 address += immediate*sizeof(intptr_t) + sizeof(intptr_t);
1337 break;
1338 case BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB:
1339 if ( symbolName == NULL )
1340 dyld::throwf("BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB missing preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM");
1341 if ( segmentIndex == -1 )
1342 dyld::throwf("BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB missing preceding BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB");
1343 count = read_uleb128(p, end);
1344 if ( !libraryOrdinalSet )
1345 dyld::throwf("BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB missing preceding BIND_OPCODE_SET_DYLIB_ORDINAL*");
1346 skip = read_uleb128(p, end);
1347 for (uint32_t i=0; i < count; ++i) {
1348 if ( (address < segmentStartAddress) || (address >= segmentEndAddress) )
1349 throwBadBindingAddress(address, segmentEndAddress, segmentIndex, start, end, p);
1350 handler(context, this, address, type, symbolName, symboFlags, addend, libraryOrdinal,
1351 &extraBindData, "", &last, false);
1352 address += skip + sizeof(intptr_t);
1353 }
1354 break;
1355 case BIND_OPCODE_THREADED:
1356 if (sizeof(intptr_t) != 8) {
1357 dyld::throwf("BIND_OPCODE_THREADED require 64-bit");
1358 return;
1359 }
1360 // Note the immediate is a sub opcode
1361 switch (immediate) {
1362 case BIND_SUBOPCODE_THREADED_SET_BIND_ORDINAL_TABLE_SIZE_ULEB:
1363 count = read_uleb128(p, end);
1364 ordinalTable.clear();
1365 // FIXME: ld64 wrote the wrong value here and we need to offset by 1 for now.
1366 ordinalTable.reserve(count + 1);
1367 useThreadedRebaseBind = true;
1368 break;
1369 case BIND_SUBOPCODE_THREADED_APPLY: {
1370 uint64_t delta = 0;
1371 do {
1372 address = segmentStartAddress + segOffset;
1373 uint64_t value = *(uint64_t*)address;
1374
1375
1376 bool isRebase = (value & (1ULL << 62)) == 0;
1377 if (isRebase) {
1378 {
1379 // Call the bind handler which knows about our bind type being set to rebase
1380 handler(context, this, address, BIND_TYPE_THREADED_REBASE, nullptr, 0, 0, 0,
1381 nullptr, "", &last, false);
1382 }
1383 } else {
1384 // the ordinal is bits [0..15]
1385 uint16_t ordinal = value & 0xFFFF;
1386 if (ordinal >= ordinalTable.count()) {
1387 dyld::throwf("bind ordinal (%d) is out of range (max=%lu) for disk pointer 0x%16llX at segIndex=%d, segOffset=0x%0lX in %s",
1388 ordinal, ordinalTable.count(),value, segmentIndex, segOffset, this->getPath());
1389 return;
1390 }
1391 std::tie(symbolName, addend, libraryOrdinal, symboFlags, type) = ordinalTable[ordinal].pack();
1392 if ( (address < segmentStartAddress) || (address >= segmentEndAddress) )
1393 throwBadBindingAddress(address, segmentEndAddress, segmentIndex, start, end, p);
1394 {
1395 handler(context, this, address, BIND_TYPE_THREADED_BIND,
1396 symbolName, symboFlags, addend, libraryOrdinal,
1397 nullptr, "", &last, false);
1398 }
1399 }
1400
1401 // The delta is bits [51..61]
1402 // And bit 62 is to tell us if we are a rebase (0) or bind (1)
1403 value &= ~(1ULL << 62);
1404 delta = ( value & 0x3FF8000000000000 ) >> 51;
1405 segOffset += delta * sizeof(intptr_t);
1406 } while ( delta != 0 );
1407 break;
1408 }
1409
1410 default:
1411 dyld::throwf("bad threaded bind subopcode 0x%02X", *p);
1412 }
1413 break;
1414 default:
1415 dyld::throwf("bad bind opcode %d in bind info", *p);
1416 }
1417 }
1418 }
1419 catch (const char* msg) {
1420 const char* newMsg = dyld::mkstringf("%s in %s", msg, this->getPath());
1421 free((void*)msg);
1422 throw newMsg;
1423 }
1424 }
1425
1426 void ImageLoaderMachOCompressed::eachLazyBind(const LinkContext& context, bind_handler handler)
1427 {
1428 try {
1429 uint8_t type = BIND_TYPE_POINTER;
1430 int segmentIndex = -1;
1431 uintptr_t address = segActualLoadAddress(0);
1432 uintptr_t segmentStartAddress = segActualLoadAddress(0);
1433 uintptr_t segmentEndAddress = segActualEndAddress(0);
1434 uintptr_t segOffset;
1435 const char* symbolName = NULL;
1436 uint8_t symboFlags = 0;
1437 long libraryOrdinal = 0;
1438 intptr_t addend = 0;
1439 const uint8_t* const start = fLinkEditBase + fDyldInfo->lazy_bind_off;
1440 const uint8_t* const end = &start[fDyldInfo->lazy_bind_size];
1441 const uint8_t* p = start;
1442 bool done = false;
1443 while ( !done && (p < end) ) {
1444 uint8_t immediate = *p & BIND_IMMEDIATE_MASK;
1445 uint8_t opcode = *p & BIND_OPCODE_MASK;
1446 ++p;
1447 switch (opcode) {
1448 case BIND_OPCODE_DONE:
1449 // there is BIND_OPCODE_DONE at end of each lazy bind, don't stop until end of whole sequence
1450 break;
1451 case BIND_OPCODE_SET_DYLIB_ORDINAL_IMM:
1452 libraryOrdinal = immediate;
1453 break;
1454 case BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB:
1455 libraryOrdinal = read_uleb128(p, end);
1456 break;
1457 case BIND_OPCODE_SET_DYLIB_SPECIAL_IMM:
1458 // the special ordinals are negative numbers
1459 if ( immediate == 0 )
1460 libraryOrdinal = 0;
1461 else {
1462 int8_t signExtended = BIND_OPCODE_MASK | immediate;
1463 libraryOrdinal = signExtended;
1464 }
1465 break;
1466 case BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
1467 symbolName = (char*)p;
1468 symboFlags = immediate;
1469 while (*p != '\0')
1470 ++p;
1471 ++p;
1472 break;
1473 case BIND_OPCODE_SET_TYPE_IMM:
1474 type = immediate;
1475 break;
1476 case BIND_OPCODE_SET_ADDEND_SLEB:
1477 addend = read_sleb128(p, end);
1478 break;
1479 case BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
1480 segmentIndex = immediate;
1481 if ( (segmentIndex >= fSegmentsCount) || (segmentIndex < 0) )
1482 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is out of range (0..%d)",
1483 segmentIndex, fSegmentsCount-1);
1484 if ( !segWriteable(segmentIndex) )
1485 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is not writable", segmentIndex);
1486 segOffset = read_uleb128(p, end);
1487 if ( segOffset > segSize(segmentIndex) )
1488 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has offset 0x%08lX beyond segment size (0x%08lX)", segOffset, segSize(segmentIndex));
1489 segmentStartAddress = segActualLoadAddress(segmentIndex);
1490 segmentEndAddress = segActualEndAddress(segmentIndex);
1491 address = segmentStartAddress + segOffset;
1492 break;
1493 case BIND_OPCODE_ADD_ADDR_ULEB:
1494 address += read_uleb128(p, end);
1495 break;
1496 case BIND_OPCODE_DO_BIND:
1497 if ( segmentIndex == -1 )
1498 dyld::throwf("BIND_OPCODE_DO_BIND missing preceding BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB");
1499 if ( (address < segmentStartAddress) || (address >= segmentEndAddress) )
1500 throwBadBindingAddress(address, segmentEndAddress, segmentIndex, start, end, p);
1501 if ( symbolName == NULL )
1502 dyld::throwf("BIND_OPCODE_DO_BIND missing preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM");
1503 handler(context, this, address, type, symbolName, symboFlags, addend, libraryOrdinal,
1504 NULL, "forced lazy ", NULL, false);
1505 address += sizeof(intptr_t);
1506 break;
1507 case BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB:
1508 case BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED:
1509 case BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB:
1510 default:
1511 dyld::throwf("bad lazy bind opcode %d", *p);
1512 }
1513 }
1514 }
1515
1516 catch (const char* msg) {
1517 const char* newMsg = dyld::mkstringf("%s in %s", msg, this->getPath());
1518 free((void*)msg);
1519 throw newMsg;
1520 }
1521 }
1522
1523 // A program built targeting 10.5 will have hybrid stubs. When used with weak symbols
1524 // the classic lazy loader is used even when running on 10.6
1525 uintptr_t ImageLoaderMachOCompressed::doBindLazySymbol(uintptr_t* lazyPointer, const LinkContext& context)
1526 {
1527 // only works with compressed LINKEDIT if classic symbol table is also present
1528 const macho_nlist* symbolTable = NULL;
1529 const char* symbolTableStrings = NULL;
1530 const dysymtab_command* dynSymbolTable = NULL;
1531 const uint32_t cmd_count = ((macho_header*)fMachOData)->ncmds;
1532 const struct load_command* const cmds = (struct load_command*)&fMachOData[sizeof(macho_header)];
1533 const struct load_command* cmd = cmds;
1534 for (uint32_t i = 0; i < cmd_count; ++i) {
1535 switch (cmd->cmd) {
1536 case LC_SYMTAB:
1537 {
1538 const struct symtab_command* symtab = (struct symtab_command*)cmd;
1539 symbolTableStrings = (const char*)&fLinkEditBase[symtab->stroff];
1540 symbolTable = (macho_nlist*)(&fLinkEditBase[symtab->symoff]);
1541 }
1542 break;
1543 case LC_DYSYMTAB:
1544 dynSymbolTable = (struct dysymtab_command*)cmd;
1545 break;
1546 }
1547 cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
1548 }
1549 // no symbol table => no lookup by address
1550 if ( (symbolTable == NULL) || (dynSymbolTable == NULL) )
1551 dyld::throwf("classic lazy binding used with compressed LINKEDIT at %p in image %s", lazyPointer, this->getPath());
1552
1553 // scan for all lazy-pointer sections
1554 const bool twoLevel = this->usesTwoLevelNameSpace();
1555 const uint32_t* const indirectTable = (uint32_t*)&fLinkEditBase[dynSymbolTable->indirectsymoff];
1556 cmd = cmds;
1557 for (uint32_t i = 0; i < cmd_count; ++i) {
1558 switch (cmd->cmd) {
1559 case LC_SEGMENT_COMMAND:
1560 {
1561 const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
1562 const struct macho_section* const sectionsStart = (struct macho_section*)((char*)seg + sizeof(struct macho_segment_command));
1563 const struct macho_section* const sectionsEnd = &sectionsStart[seg->nsects];
1564 for (const struct macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
1565 const uint8_t type = sect->flags & SECTION_TYPE;
1566 uint32_t symbolIndex = INDIRECT_SYMBOL_LOCAL;
1567 if ( type == S_LAZY_SYMBOL_POINTERS ) {
1568 const size_t pointerCount = sect->size / sizeof(uintptr_t);
1569 uintptr_t* const symbolPointers = (uintptr_t*)(sect->addr + fSlide);
1570 if ( (lazyPointer >= symbolPointers) && (lazyPointer < &symbolPointers[pointerCount]) ) {
1571 const uint32_t indirectTableOffset = sect->reserved1;
1572 const size_t lazyIndex = lazyPointer - symbolPointers;
1573 symbolIndex = indirectTable[indirectTableOffset + lazyIndex];
1574 }
1575 }
1576 if ( (symbolIndex != INDIRECT_SYMBOL_ABS) && (symbolIndex != INDIRECT_SYMBOL_LOCAL) ) {
1577 const macho_nlist* symbol = &symbolTable[symbolIndex];
1578 const char* symbolName = &symbolTableStrings[symbol->n_un.n_strx];
1579 int libraryOrdinal = GET_LIBRARY_ORDINAL(symbol->n_desc);
1580 if ( !twoLevel || context.bindFlat )
1581 libraryOrdinal = BIND_SPECIAL_DYLIB_FLAT_LOOKUP;
1582 uintptr_t ptrToBind = (uintptr_t)lazyPointer;
1583 uintptr_t symbolAddr = bindAt(context, this, ptrToBind, BIND_TYPE_POINTER, symbolName, 0, 0, libraryOrdinal,
1584 NULL, "lazy ", NULL);
1585 ++fgTotalLazyBindFixups;
1586 return symbolAddr;
1587 }
1588 }
1589 }
1590 break;
1591 }
1592 cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
1593 }
1594 dyld::throwf("lazy pointer not found at address %p in image %s", lazyPointer, this->getPath());
1595 }
1596
1597
1598
1599 uintptr_t ImageLoaderMachOCompressed::doBindFastLazySymbol(uint32_t lazyBindingInfoOffset, const LinkContext& context,
1600 void (*lock)(), void (*unlock)())
1601 {
1602 // <rdar://problem/8663923> race condition with flat-namespace lazy binding
1603 if ( this->usesTwoLevelNameSpace() ) {
1604 // two-level namespace lookup does not require lock because dependents can't be unloaded before this image
1605 }
1606 else {
1607 // acquire dyld global lock
1608 if ( lock != NULL )
1609 lock();
1610 }
1611
1612 const uint8_t* const start = fLinkEditBase + fDyldInfo->lazy_bind_off;
1613 const uint8_t* const end = &start[fDyldInfo->lazy_bind_size];
1614 uint8_t segIndex;
1615 uintptr_t segOffset;
1616 int libraryOrdinal;
1617 const char* symbolName;
1618 bool doneAfterBind;
1619 uintptr_t result;
1620 do {
1621 if ( ! getLazyBindingInfo(lazyBindingInfoOffset, start, end, &segIndex, &segOffset, &libraryOrdinal, &symbolName, &doneAfterBind) )
1622 dyld::throwf("bad lazy bind info");
1623
1624 if ( segIndex >= fSegmentsCount )
1625 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is too large (0..%d)",
1626 segIndex, fSegmentsCount-1);
1627 if ( segOffset > segSize(segIndex) )
1628 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has offset 0x%08lX beyond segment size (0x%08lX)", segOffset, segSize(segIndex));
1629 uintptr_t address = segActualLoadAddress(segIndex) + segOffset;
1630 result = bindAt(context, this, address, BIND_TYPE_POINTER, symbolName, 0, 0, libraryOrdinal,
1631 NULL, "lazy ", NULL, true);
1632 // <rdar://problem/24140465> Some old apps had multiple lazy symbols bound at once
1633 } while (!doneAfterBind && !context.strictMachORequired);
1634
1635 if ( !this->usesTwoLevelNameSpace() ) {
1636 // release dyld global lock
1637 if ( unlock != NULL )
1638 unlock();
1639 }
1640 return result;
1641 }
1642
1643 void ImageLoaderMachOCompressed::initializeCoalIterator(CoalIterator& it, unsigned int loadOrder, unsigned)
1644 {
1645 it.image = this;
1646 it.symbolName = " ";
1647 it.loadOrder = loadOrder;
1648 it.weakSymbol = false;
1649 it.symbolMatches = false;
1650 it.done = false;
1651 it.curIndex = 0;
1652 it.endIndex = (this->fDyldInfo ? this->fDyldInfo->weak_bind_size : 0);
1653 it.address = 0;
1654 it.type = 0;
1655 it.addend = 0;
1656 }
1657
1658
1659 bool ImageLoaderMachOCompressed::incrementCoalIterator(CoalIterator& it)
1660 {
1661 if ( it.done )
1662 return false;
1663
1664 if ( (this->fDyldInfo == nullptr) || (this->fDyldInfo->weak_bind_size == 0) ) {
1665 /// hmmm, ld set MH_WEAK_DEFINES or MH_BINDS_TO_WEAK, but there is no weak binding info
1666 it.done = true;
1667 it.symbolName = "~~~";
1668 return true;
1669 }
1670 const uint8_t* start = fLinkEditBase + fDyldInfo->weak_bind_off;
1671 const uint8_t* p = start + it.curIndex;
1672 const uint8_t* end = fLinkEditBase + fDyldInfo->weak_bind_off + this->fDyldInfo->weak_bind_size;
1673 uintptr_t count;
1674 uintptr_t skip;
1675 uintptr_t segOffset;
1676 while ( p < end ) {
1677 uint8_t immediate = *p & BIND_IMMEDIATE_MASK;
1678 uint8_t opcode = *p & BIND_OPCODE_MASK;
1679 ++p;
1680 switch (opcode) {
1681 case BIND_OPCODE_DONE:
1682 it.done = true;
1683 it.curIndex = p - start;
1684 it.symbolName = "~~~"; // sorts to end
1685 return true;
1686 case BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
1687 it.symbolName = (char*)p;
1688 it.weakSymbol = ((immediate & BIND_SYMBOL_FLAGS_NON_WEAK_DEFINITION) == 0);
1689 it.symbolMatches = false;
1690 while (*p != '\0')
1691 ++p;
1692 ++p;
1693 it.curIndex = p - start;
1694 return false;
1695 case BIND_OPCODE_SET_TYPE_IMM:
1696 it.type = immediate;
1697 break;
1698 case BIND_OPCODE_SET_ADDEND_SLEB:
1699 it.addend = read_sleb128(p, end);
1700 break;
1701 case BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
1702 if ( immediate >= fSegmentsCount )
1703 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is too large (0..%d)",
1704 immediate, fSegmentsCount-1);
1705 #if __arm__
1706 // <rdar://problem/23138428> iOS app compatibility
1707 if ( !segWriteable(immediate) && it.image->isPositionIndependentExecutable() )
1708 #elif TEXT_RELOC_SUPPORT
1709 // <rdar://problem/23479396&23590867> i386 OS X app compatibility
1710 if ( !segWriteable(immediate) && !segHasRebaseFixUps(immediate) && !segHasBindFixUps(immediate)
1711 && (!it.image->isExecutable() || it.image->isPositionIndependentExecutable()) )
1712 #else
1713 if ( !segWriteable(immediate) )
1714 #endif
1715 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB targets segment %s which is not writable", segName(immediate));
1716 segOffset = read_uleb128(p, end);
1717 if ( segOffset > segSize(immediate) )
1718 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has offset 0x%08lX beyond segment size (0x%08lX)", segOffset, segSize(immediate));
1719 it.address = segActualLoadAddress(immediate) + segOffset;
1720 break;
1721 case BIND_OPCODE_ADD_ADDR_ULEB:
1722 it.address += read_uleb128(p, end);
1723 break;
1724 case BIND_OPCODE_DO_BIND:
1725 it.address += sizeof(intptr_t);
1726 break;
1727 case BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB:
1728 it.address += read_uleb128(p, end) + sizeof(intptr_t);
1729 break;
1730 case BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED:
1731 it.address += immediate*sizeof(intptr_t) + sizeof(intptr_t);
1732 break;
1733 case BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB:
1734 count = read_uleb128(p, end);
1735 skip = read_uleb128(p, end);
1736 for (uint32_t i=0; i < count; ++i) {
1737 it.address += skip + sizeof(intptr_t);
1738 }
1739 break;
1740 default:
1741 dyld::throwf("bad weak bind opcode '%d' found after processing %d bytes in '%s'", *p, (int)(p-start), this->getPath());
1742 }
1743 }
1744 /// hmmm, BIND_OPCODE_DONE is missing...
1745 it.done = true;
1746 it.symbolName = "~~~";
1747 //dyld::log("missing BIND_OPCODE_DONE for image %s\n", this->getPath());
1748 return true;
1749 }
1750
1751 uintptr_t ImageLoaderMachOCompressed::getAddressCoalIterator(CoalIterator& it, const LinkContext& context)
1752 {
1753 //dyld::log("looking for %s in %s\n", it.symbolName, this->getPath());
1754 const ImageLoader* foundIn = NULL;
1755 const ImageLoader::Symbol* sym = this->findShallowExportedSymbol(it.symbolName, &foundIn);
1756 if ( sym != NULL ) {
1757 //dyld::log("sym=%p, foundIn=%p\n", sym, foundIn);
1758 return foundIn->getExportedSymbolAddress(sym, context, this);
1759 }
1760 return 0;
1761 }
1762
1763
1764 void ImageLoaderMachOCompressed::updateUsesCoalIterator(CoalIterator& it, uintptr_t value, ImageLoader* targetImage, unsigned targetIndex, const LinkContext& context)
1765 {
1766 // <rdar://problem/6570879> weak binding done too early with inserted libraries
1767 if ( this->getState() < dyld_image_state_bound )
1768 return;
1769
1770 if ( fDyldInfo == nullptr )
1771 return;
1772
1773 const uint8_t* start = fLinkEditBase + fDyldInfo->weak_bind_off;
1774 const uint8_t* p = start + it.curIndex;
1775 const uint8_t* end = fLinkEditBase + fDyldInfo->weak_bind_off + this->fDyldInfo->weak_bind_size;
1776
1777 uint8_t type = it.type;
1778 uintptr_t address = it.address;
1779 const char* symbolName = it.symbolName;
1780 intptr_t addend = it.addend;
1781 uintptr_t count;
1782 uintptr_t skip;
1783 uintptr_t segOffset;
1784 bool done = false;
1785 bool boundSomething = false;
1786 while ( !done && (p < end) ) {
1787 uint8_t immediate = *p & BIND_IMMEDIATE_MASK;
1788 uint8_t opcode = *p & BIND_OPCODE_MASK;
1789 ++p;
1790 switch (opcode) {
1791 case BIND_OPCODE_DONE:
1792 done = true;
1793 break;
1794 case BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
1795 done = true;
1796 break;
1797 case BIND_OPCODE_SET_TYPE_IMM:
1798 type = immediate;
1799 break;
1800 case BIND_OPCODE_SET_ADDEND_SLEB:
1801 addend = read_sleb128(p, end);
1802 break;
1803 case BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
1804 if ( immediate >= fSegmentsCount )
1805 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has segment %d which is too large (0..%d)",
1806 immediate, fSegmentsCount-1);
1807 #if __arm__
1808 // <rdar://problem/23138428> iOS app compatibility
1809 if ( !segWriteable(immediate) && it.image->isPositionIndependentExecutable() )
1810 #elif TEXT_RELOC_SUPPORT
1811 // <rdar://problem/23479396&23590867> i386 OS X app compatibility
1812 if ( !segWriteable(immediate) && !segHasRebaseFixUps(immediate) && !segHasBindFixUps(immediate)
1813 && (!it.image->isExecutable() || it.image->isPositionIndependentExecutable()) )
1814 #else
1815 if ( !segWriteable(immediate) )
1816 #endif
1817 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB targets segment %s which is not writable", segName(immediate));
1818 segOffset = read_uleb128(p, end);
1819 if ( segOffset > segSize(immediate) )
1820 dyld::throwf("BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB has offset 0x%08lX beyond segment size (0x%08lX)", segOffset, segSize(immediate));
1821 address = segActualLoadAddress(immediate) + segOffset;
1822 break;
1823 case BIND_OPCODE_ADD_ADDR_ULEB:
1824 address += read_uleb128(p, end);
1825 break;
1826 case BIND_OPCODE_DO_BIND:
1827 bindLocation(context, this->imageBaseAddress(), address, value, type, symbolName, addend, this->getPath(), targetImage ? targetImage->getPath() : NULL, "weak ", NULL, fSlide);
1828 boundSomething = true;
1829 address += sizeof(intptr_t);
1830 break;
1831 case BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB:
1832 bindLocation(context, this->imageBaseAddress(), address, value, type, symbolName, addend, this->getPath(), targetImage ? targetImage->getPath() : NULL, "weak ", NULL, fSlide);
1833 boundSomething = true;
1834 address += read_uleb128(p, end) + sizeof(intptr_t);
1835 break;
1836 case BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED:
1837 bindLocation(context, this->imageBaseAddress(), address, value, type, symbolName, addend, this->getPath(), targetImage ? targetImage->getPath() : NULL, "weak ", NULL, fSlide);
1838 boundSomething = true;
1839 address += immediate*sizeof(intptr_t) + sizeof(intptr_t);
1840 break;
1841 case BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB:
1842 count = read_uleb128(p, end);
1843 skip = read_uleb128(p, end);
1844 for (uint32_t i=0; i < count; ++i) {
1845 bindLocation(context, this->imageBaseAddress(), address, value, type, symbolName, addend, this->getPath(), targetImage ? targetImage->getPath() : NULL, "weak ", NULL, fSlide);
1846 boundSomething = true;
1847 address += skip + sizeof(intptr_t);
1848 }
1849 break;
1850 default:
1851 dyld::throwf("bad bind opcode %d in weak binding info", *p);
1852 }
1853 }
1854 // C++ weak coalescing cannot be tracked by reference counting. Error on side of never unloading.
1855 if ( boundSomething && (targetImage != this) )
1856 context.addDynamicReference(this, targetImage);
1857 }
1858
1859 uintptr_t ImageLoaderMachOCompressed::interposeAt(const LinkContext& context, ImageLoaderMachOCompressed* image,
1860 uintptr_t addr, uint8_t type, const char*,
1861 uint8_t, intptr_t, long,
1862 ExtraBindData *extraBindData,
1863 const char*, LastLookup*, bool runResolver)
1864 {
1865 if ( type == BIND_TYPE_POINTER ) {
1866 uintptr_t* fixupLocation = (uintptr_t*)addr;
1867 uintptr_t curValue = *fixupLocation;
1868 uintptr_t newValue = interposedAddress(context, curValue, image);
1869 if ( newValue != curValue) {
1870 *fixupLocation = newValue;
1871 }
1872 }
1873 return 0;
1874 }
1875
1876 void ImageLoaderMachOCompressed::doInterpose(const LinkContext& context)
1877 {
1878 if ( context.verboseInterposing )
1879 dyld::log("dyld: interposing %lu tuples onto image: %s\n", fgInterposingTuples.size(), this->getPath());
1880
1881 const dyld3::MachOAnalyzer* ma = (dyld3::MachOAnalyzer*)fMachOData;
1882 if ( !ma->hasChainedFixups() && (fDyldInfo != nullptr) ) {
1883 // Note: all binds that happen as part of normal loading and fixups will have interposing applied.
1884 // There is only two cases where we need to parse bind opcodes and apply interposing:
1885
1886 // 1) Lazy pointers are either not bound yet, or in dyld cache they are prebound (to uninterposed target)
1887 eachLazyBind(context, ^(const LinkContext& ctx, ImageLoaderMachOCompressed* image,
1888 uintptr_t addr, uint8_t type, const char* symbolName,
1889 uint8_t symbolFlags, intptr_t addend, long libraryOrdinal,
1890 ExtraBindData *extraBindData,
1891 const char* msg, LastLookup* last, bool runResolver) {
1892 return ImageLoaderMachOCompressed::interposeAt(ctx, image, addr, type, symbolName, symbolFlags,
1893 addend, libraryOrdinal, extraBindData,
1894 msg, last, runResolver);
1895 });
1896
1897 // 2) non-lazy pointers in the dyld cache need to be interposed
1898 if ( ma->inDyldCache() ) {
1899 eachBind(context, ^(const LinkContext& ctx, ImageLoaderMachOCompressed* image,
1900 uintptr_t addr, uint8_t type, const char* symbolName,
1901 uint8_t symbolFlags, intptr_t addend, long libraryOrdinal,
1902 ExtraBindData *extraBindData,
1903 const char* msg, LastLookup* last, bool runResolver) {
1904 return ImageLoaderMachOCompressed::interposeAt(ctx, image, addr, type, symbolName, symbolFlags,
1905 addend, libraryOrdinal, extraBindData,
1906 msg, last, runResolver);
1907 });
1908 }
1909
1910 }
1911 }
1912
1913
1914 uintptr_t ImageLoaderMachOCompressed::dynamicInterposeAt(const LinkContext& context, ImageLoaderMachOCompressed* image,
1915 uintptr_t addr, uint8_t type, const char* symbolName,
1916 uint8_t, intptr_t, long,
1917 ExtraBindData *extraBindData,
1918 const char*, LastLookup*, bool runResolver)
1919 {
1920 if ( type == BIND_TYPE_POINTER ) {
1921 uintptr_t* fixupLocation = (uintptr_t*)addr;
1922 uintptr_t value = *fixupLocation;
1923 // don't apply interposing to table entries.
1924 if ( (context.dynamicInterposeArray <= (void*)addr) && ((void*)addr < &context.dynamicInterposeArray[context.dynamicInterposeCount]) )
1925 return 0;
1926 for(size_t i=0; i < context.dynamicInterposeCount; ++i) {
1927 if ( value == (uintptr_t)context.dynamicInterposeArray[i].replacee ) {
1928 if ( context.verboseInterposing ) {
1929 dyld::log("dyld: dynamic interposing: at %p replace %p with %p in %s\n",
1930 fixupLocation, context.dynamicInterposeArray[i].replacee, context.dynamicInterposeArray[i].replacement, image->getPath());
1931 }
1932 *fixupLocation = (uintptr_t)context.dynamicInterposeArray[i].replacement;
1933 }
1934 }
1935 }
1936 return 0;
1937 }
1938
1939 void ImageLoaderMachOCompressed::dynamicInterpose(const LinkContext& context)
1940 {
1941 if ( context.verboseInterposing )
1942 dyld::log("dyld: dynamic interposing %lu tuples onto image: %s\n", context.dynamicInterposeCount, this->getPath());
1943
1944 // update already bound references to symbols
1945 eachBind(context, ^(const LinkContext& ctx, ImageLoaderMachOCompressed* image,
1946 uintptr_t addr, uint8_t type, const char* symbolName,
1947 uint8_t symbolFlags, intptr_t addend, long libraryOrdinal,
1948 ExtraBindData *extraBindData,
1949 const char* msg, LastLookup* last, bool runResolver) {
1950 return ImageLoaderMachOCompressed::dynamicInterposeAt(ctx, image, addr, type, symbolName, symbolFlags,
1951 addend, libraryOrdinal, extraBindData,
1952 msg, last, runResolver);
1953 });
1954 eachLazyBind(context, ^(const LinkContext& ctx, ImageLoaderMachOCompressed* image,
1955 uintptr_t addr, uint8_t type, const char* symbolName,
1956 uint8_t symbolFlags, intptr_t addend, long libraryOrdinal,
1957 ExtraBindData *extraBindData,
1958 const char* msg, LastLookup* last, bool runResolver) {
1959 return ImageLoaderMachOCompressed::dynamicInterposeAt(ctx, image, addr, type, symbolName, symbolFlags,
1960 addend, libraryOrdinal, extraBindData,
1961 msg, last, runResolver);
1962 });
1963 }
1964
1965 const char* ImageLoaderMachOCompressed::findClosestSymbol(const void* addr, const void** closestAddr) const
1966 {
1967 return ImageLoaderMachO::findClosestSymbol((mach_header*)fMachOData, addr, closestAddr);
1968 }
1969
1970
1971 #if PREBOUND_IMAGE_SUPPORT
1972 void ImageLoaderMachOCompressed::resetPreboundLazyPointers(const LinkContext& context)
1973 {
1974 // no way to back off a prebound compress image
1975 }
1976 #endif
1977
1978
1979 #if __arm__ || __x86_64__
1980 void ImageLoaderMachOCompressed::updateAlternateLazyPointer(uint8_t* stub, void** originalLazyPointerAddr, const LinkContext& context)
1981 {
1982 #if __arm__
1983 uint32_t* instructions = (uint32_t*)stub;
1984 // sanity check this is a stub we understand
1985 if ( (instructions[0] != 0xe59fc004) || (instructions[1] != 0xe08fc00c) || (instructions[2] != 0xe59cf000) )
1986 return;
1987
1988 void** lazyPointerAddr = (void**)(instructions[3] + (stub + 12));
1989 #endif
1990 #if __x86_64__
1991 // sanity check this is a stub we understand
1992 if ( (stub[0] != 0xFF) || (stub[1] != 0x25) )
1993 return;
1994 int32_t ripOffset = *((int32_t*)(&stub[2]));
1995 void** lazyPointerAddr = (void**)(ripOffset + stub + 6);
1996 #endif
1997
1998 // if stub does not use original lazy pointer (meaning it was optimized by update_dyld_shared_cache)
1999 if ( lazyPointerAddr != originalLazyPointerAddr ) {
2000 // <rdar://problem/12928448> only de-optimization lazy pointers if they are part of shared cache not loaded (because overridden)
2001 const ImageLoader* lazyPointerImage = context.findImageContainingAddress(lazyPointerAddr);
2002 if ( lazyPointerImage != NULL )
2003 return;
2004
2005 // copy newly re-bound lazy pointer value to shared lazy pointer
2006 *lazyPointerAddr = *originalLazyPointerAddr;
2007
2008 if ( context.verboseBind )
2009 dyld::log("dyld: alter bind: %s: *0x%08lX = 0x%08lX \n",
2010 this->getShortName(), (long)lazyPointerAddr, (long)*originalLazyPointerAddr);
2011 }
2012 }
2013 #endif
2014
2015
2016 // <rdar://problem/8890875> overriding shared cache dylibs with resolvers fails
2017 void ImageLoaderMachOCompressed::updateOptimizedLazyPointers(const LinkContext& context)
2018 {
2019 #if __arm__ || __x86_64__
2020 // find stubs and indirect symbol table
2021 const struct macho_section* stubsSection = NULL;
2022 const dysymtab_command* dynSymbolTable = NULL;
2023 const macho_header* mh = (macho_header*)fMachOData;
2024 const uint32_t cmd_count = mh->ncmds;
2025 const struct load_command* const cmds = (struct load_command*)&fMachOData[sizeof(macho_header)];
2026 const struct load_command* cmd = cmds;
2027 for (uint32_t i = 0; i < cmd_count; ++i) {
2028 if (cmd->cmd == LC_SEGMENT_COMMAND) {
2029 const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
2030 const struct macho_section* const sectionsStart = (struct macho_section*)((char*)seg + sizeof(struct macho_segment_command));
2031 const struct macho_section* const sectionsEnd = &sectionsStart[seg->nsects];
2032 for (const struct macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
2033 const uint8_t type = sect->flags & SECTION_TYPE;
2034 if ( type == S_SYMBOL_STUBS )
2035 stubsSection = sect;
2036 }
2037 }
2038 else if ( cmd->cmd == LC_DYSYMTAB ) {
2039 dynSymbolTable = (struct dysymtab_command*)cmd;
2040 }
2041 cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
2042 }
2043 if ( dynSymbolTable == NULL )
2044 return;
2045 const uint32_t* const indirectTable = (uint32_t*)&fLinkEditBase[dynSymbolTable->indirectsymoff];
2046 if ( stubsSection == NULL )
2047 return;
2048 const uint32_t stubsSize = stubsSection->reserved2;
2049 const uint32_t stubsCount = (uint32_t)(stubsSection->size / stubsSize);
2050 const uint32_t stubsIndirectTableOffset = stubsSection->reserved1;
2051 if ( (stubsIndirectTableOffset+stubsCount) > dynSymbolTable->nindirectsyms )
2052 return;
2053 uint8_t* const stubsAddr = (uint8_t*)(stubsSection->addr + this->fSlide);
2054
2055 // for each lazy pointer section
2056 cmd = cmds;
2057 for (uint32_t i = 0; i < cmd_count; ++i) {
2058 if (cmd->cmd == LC_SEGMENT_COMMAND) {
2059 const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
2060 const struct macho_section* const sectionsStart = (struct macho_section*)((char*)seg + sizeof(struct macho_segment_command));
2061 const struct macho_section* const sectionsEnd = &sectionsStart[seg->nsects];
2062 for (const struct macho_section* lazyPointerSection=sectionsStart; lazyPointerSection < sectionsEnd; ++lazyPointerSection) {
2063 const uint8_t type = lazyPointerSection->flags & SECTION_TYPE;
2064 if ( type != S_LAZY_SYMBOL_POINTERS )
2065 continue;
2066 const uint32_t lazyPointersCount = (uint32_t)(lazyPointerSection->size / sizeof(void*));
2067 const uint32_t lazyPointersIndirectTableOffset = lazyPointerSection->reserved1;
2068 if ( (lazyPointersIndirectTableOffset+lazyPointersCount) > dynSymbolTable->nindirectsyms )
2069 continue;
2070 void** const lazyPointersAddr = (void**)(lazyPointerSection->addr + this->fSlide);
2071 // for each lazy pointer
2072 for(uint32_t lpIndex=0; lpIndex < lazyPointersCount; ++lpIndex) {
2073 const uint32_t lpSymbolIndex = indirectTable[lazyPointersIndirectTableOffset+lpIndex];
2074 // find matching stub and validate it uses this lazy pointer
2075 for(uint32_t stubIndex=0; stubIndex < stubsCount; ++stubIndex) {
2076 if ( indirectTable[stubsIndirectTableOffset+stubIndex] == lpSymbolIndex ) {
2077 this->updateAlternateLazyPointer(stubsAddr+stubIndex*stubsSize, &lazyPointersAddr[lpIndex], context);
2078 break;
2079 }
2080 }
2081 }
2082
2083 }
2084 }
2085 cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
2086 }
2087
2088 #endif
2089 }
2090
2091
2092 void ImageLoaderMachOCompressed::registerEncryption(const encryption_info_command* encryptCmd, const LinkContext& context)
2093 {
2094 #if (__arm__ || __arm64__) && !TARGET_OS_SIMULATOR
2095 if ( encryptCmd == NULL )
2096 return;
2097 // fMachOData not set up yet, need to manually find mach_header
2098 const mach_header* mh = NULL;
2099 for(unsigned int i=0; i < fSegmentsCount; ++i) {
2100 if ( (segFileOffset(i) == 0) && (segFileSize(i) != 0) ) {
2101 mh = (mach_header*)segActualLoadAddress(i);
2102 void* start = ((uint8_t*)mh) + encryptCmd->cryptoff;
2103 size_t len = encryptCmd->cryptsize;
2104 uint32_t cputype = mh->cputype;
2105 uint32_t cpusubtype = mh->cpusubtype;
2106 uint32_t cryptid = encryptCmd->cryptid;
2107 if (context.verboseMapping) {
2108 dyld::log(" 0x%08lX->0x%08lX configured for FairPlay decryption\n", (long)start, (long)start+len);
2109 }
2110 int result = mremap_encrypted(start, len, cryptid, cputype, cpusubtype);
2111 if ( result != 0 ) {
2112 dyld::throwf("mremap_encrypted() => %d, errno=%d for %s\n", result, errno, this->getPath());
2113 }
2114 return;
2115 }
2116 }
2117 #endif
2118 }
2119
2120
2121
mirror of dyld