dyld3/shared-cache/update_dyld_shared_cache.cpp

   1 /* -*- mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
   2  *
   3  * Copyright (c) 2014 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 #include <sys/types.h>
  26 #include <sys/stat.h>
  27 #include <sys/mman.h>
  28 #include <mach/mach.h>
  29 #include <mach/mach_time.h>
  30 #include <mach-o/dyld.h>
  31 #include <limits.h>
  32 #include <stdarg.h>
  33 #include <stdio.h>
  34 #include <stdlib.h>
  35 #include <math.h>
  36 #include <fcntl.h>
  37 #include <dlfcn.h>
  38 #include <signal.h>
  39 #include <errno.h>
  40 #include <assert.h>
  41 #include <sys/uio.h>
  42 #include <unistd.h>
  43 #include <sys/param.h>
  44 #include <sys/sysctl.h>
  45 #include <sys/resource.h>
  46 #include <dirent.h>
  47 #include <rootless.h>
  48 #include <dscsym.h>
  49 #include <dispatch/dispatch.h>
  50 #include <pthread/pthread.h>
  51 #include <Bom/Bom.h>
  52 #include <CoreFoundation/CoreFoundation.h>
  53
  54 #include <algorithm>
  55 #include <vector>
  56 #include <unordered_set>
  57 #include <unordered_set>
  58 #include <iostream>
  59 #include <fstream>
  60
  61 #include "FileUtils.h"
  62 #include "StringUtils.h"
  63 #include "DyldSharedCache.h"
  64 #include "MachOFile.h"
  65 #include "MachOAnalyzer.h"
  66 #include "ClosureFileSystemPhysical.h"
  67
  68 struct MappedMachOsByCategory
  69 {
  70     std::string                                 archName;
  71     std::vector<DyldSharedCache::MappedMachO>   dylibsForCache;
  72     std::vector<DyldSharedCache::MappedMachO>   otherDylibsAndBundles;
  73     std::vector<DyldSharedCache::MappedMachO>   mainExecutables;
  74 };
  75
  76 static const char* sAllowedPrefixes[] = {
  77     "/bin/",
  78     "/sbin/",
  79     "/usr/",
  80     "/System",
  81     "/Applications/App Store.app/",
  82     "/Applications/Automator.app/",
  83     "/Applications/Calculator.app/",
  84     "/Applications/Calendar.app/",
  85     "/Applications/Chess.app/",
  86     "/Applications/Contacts.app/",
  87 //    "/Applications/DVD Player.app/",
  88     "/Applications/Dashboard.app/",
  89     "/Applications/Dictionary.app/",
  90     "/Applications/FaceTime.app/",
  91     "/Applications/Font Book.app/",
  92     "/Applications/Image Capture.app/",
  93     "/Applications/Launchpad.app/",
  94     "/Applications/Mail.app/",
  95     "/Applications/Maps.app/",
  96     "/Applications/Messages.app/",
  97     "/Applications/Mission Control.app/",
  98     "/Applications/Notes.app/",
  99     "/Applications/Photo Booth.app/",
 100 //    "/Applications/Photos.app/",
 101     "/Applications/Preview.app/",
 102     "/Applications/QuickTime Player.app/",
 103     "/Applications/Reminders.app/",
 104     "/Applications/Safari.app/",
 105     "/Applications/Siri.app/",
 106     "/Applications/Stickies.app/",
 107     "/Applications/System Preferences.app/",
 108     "/Applications/TextEdit.app/",
 109     "/Applications/Time Machine.app/",
 110     "/Applications/iBooks.app/",
 111     "/Applications/iTunes.app/",
 112     "/Applications/Utilities/Activity Monitor.app",
 113     "/Applications/Utilities/AirPort Utility.app",
 114     "/Applications/Utilities/Audio MIDI Setup.app",
 115     "/Applications/Utilities/Bluetooth File Exchange.app",
 116     "/Applications/Utilities/Boot Camp Assistant.app",
 117     "/Applications/Utilities/ColorSync Utility.app",
 118     "/Applications/Utilities/Console.app",
 119     "/Applications/Utilities/Digital Color Meter.app",
 120     "/Applications/Utilities/Disk Utility.app",
 121     "/Applications/Utilities/Grab.app",
 122     "/Applications/Utilities/Grapher.app",
 123     "/Applications/Utilities/Keychain Access.app",
 124     "/Applications/Utilities/Migration Assistant.app",
 125     "/Applications/Utilities/Script Editor.app",
 126     "/Applications/Utilities/System Information.app",
 127     "/Applications/Utilities/Terminal.app",
 128     "/Applications/Utilities/VoiceOver Utility.app",
 129     "/Library/CoreMediaIO/Plug-Ins/DAL/"                // temp until plugins moved or closured working
 130 };
 131
 132 static const char* sDontUsePrefixes[] = {
 133     "/usr/share",
 134     "/usr/local/",
 135     "/System/Library/Assets",
 136     "/System/Library/StagedFrameworks",
 137     "/System/Library/Kernels/",
 138     "/bin/zsh",                             // until <rdar://31026756> is fixed
 139     "/System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/Metadata.framework/Versions/A/Support/mdworker", // these load third party plugins
 140     "/usr/bin/mdimport", // these load third party plugins
 141     "/System/Library/Developer/CoreSimulator/",  // ignore Marzipan
 142 };
 143
 144
 145 static bool verbose = false;
 146
 147
 148
 149 static bool addIfMachO(const dyld3::closure::FileSystem& fileSystem, const std::string& runtimePath, const struct stat& statBuf, bool requireSIP, std::vector<MappedMachOsByCategory>& files)
 150 {
 151     // don't precompute closure info for any debug or profile dylibs
 152     if ( endsWith(runtimePath, "_profile.dylib") || endsWith(runtimePath, "_debug.dylib") || endsWith(runtimePath, "_profile") || endsWith(runtimePath, "_debug") )
 153         return false;
 154     if ( startsWith(runtimePath, "/usr/lib/system/introspection/") )
 155         return false;
 156
 157     auto warningHandler = ^(const char* msg) {
 158         if ( verbose )
 159             fprintf(stderr, "update_dyld_shared_cache: warning: cannot build dlopen closure for '%s' because %s\n", runtimePath.c_str(), msg);
 160     };
 161
 162     bool result = false;
 163     for (MappedMachOsByCategory& file : files) {
 164         Diagnostics diag;
 165         dyld3::closure::LoadedFileInfo loadedFileInfo = dyld3::MachOAnalyzer::load(diag, fileSystem, runtimePath.c_str(), file.archName.c_str(), dyld3::Platform::macOS);
 166         const dyld3::MachOAnalyzer* ma = (const dyld3::MachOAnalyzer*)loadedFileInfo.fileContent;
 167         if ( ma != nullptr ) {
 168             bool sipProtected = false; // isProtectedBySIP(fd);
 169             bool issetuid     = false;
 170             if ( ma->isDynamicExecutable() ) {
 171                 // When SIP enabled, only build closures for SIP protected programs
 172                 if ( !requireSIP || sipProtected ) {
 173                     //fprintf(stderr, "requireSIP=%d, sipProtected=%d, path=%s\n", requireSIP, sipProtected, fullPath.c_str());
 174                     issetuid = (statBuf.st_mode & (S_ISUID|S_ISGID));
 175                     file.mainExecutables.emplace_back(runtimePath, ma, loadedFileInfo.sliceLen, issetuid, sipProtected, loadedFileInfo.sliceOffset, statBuf.st_mtime, statBuf.st_ino);
 176                 }
 177             }
 178             else if ( ma->canBePlacedInDyldCache(runtimePath.c_str(), ^(const char* msg) {}) ) {
 179                 // when SIP is enabled, only dylib protected by SIP can go in cache
 180                 if ( !requireSIP || sipProtected )
 181                     file.dylibsForCache.emplace_back(runtimePath, ma, loadedFileInfo.sliceLen, issetuid, sipProtected, loadedFileInfo.sliceOffset, statBuf.st_mtime, statBuf.st_ino);
 182                 else if ( ma->canHavePrecomputedDlopenClosure(runtimePath.c_str(), warningHandler) )
 183                     file.otherDylibsAndBundles.emplace_back(runtimePath, ma, loadedFileInfo.sliceLen, issetuid, sipProtected, loadedFileInfo.sliceOffset, statBuf.st_mtime, statBuf.st_ino);
 184             }
 185             else {
 186                 if ( ma->isDylib() ) {
 187                     std::string installName = ma->installName();
 188                     if ( startsWith(installName, "@") && !contains(runtimePath, ".app/") && !contains(runtimePath, ".xpc/") ) {
 189                         if ( startsWith(runtimePath, "/usr/lib/") || startsWith(runtimePath, "/System/Library/") )
 190                             fprintf(stderr, "update_dyld_shared_cache: warning @rpath install name for system framework: %s\n", runtimePath.c_str());
 191                     }
 192                 }
 193                 else if ( ma->canHavePrecomputedDlopenClosure(runtimePath.c_str(), warningHandler) ) {
 194                     file.otherDylibsAndBundles.emplace_back(runtimePath, ma, loadedFileInfo.sliceLen, issetuid, sipProtected, loadedFileInfo.sliceOffset, statBuf.st_mtime, statBuf.st_ino);
 195                 }
 196             }
 197             result = true;
 198         }
 199     }
 200
 201     return result;
 202 }
 203
 204 static void findAllFiles(const std::vector<std::string>& pathPrefixes, bool requireSIP, std::vector<MappedMachOsByCategory>& files)
 205 {
 206     std::unordered_set<std::string> skipDirs;
 207     for (const char* s : sDontUsePrefixes)
 208         skipDirs.insert(s);
 209
 210     __block std::unordered_set<std::string> alreadyUsed;
 211     bool multiplePrefixes = (pathPrefixes.size() > 1);
 212     for (const std::string& prefix : pathPrefixes) {
 213         // get all files from overlay for this search dir
 214         dyld3::closure::FileSystemPhysical fileSystem(prefix.c_str());
 215         for (const char* searchDir : sAllowedPrefixes ) {
 216             iterateDirectoryTree(prefix, searchDir, ^(const std::string& dirPath) { return (skipDirs.count(dirPath) != 0); }, ^(const std::string& path, const struct stat& statBuf) {
 217                 // ignore files that don't have 'x' bit set (all runnable mach-o files do)
 218                 const bool hasXBit = ((statBuf.st_mode & S_IXOTH) == S_IXOTH);
 219                 if ( !hasXBit && !endsWith(path, ".dylib") )
 220                     return;
 221
 222                 // ignore files too small
 223                 if ( statBuf.st_size < 0x3000 )
 224                     return;
 225
 226                 // don't add paths already found using previous prefix
 227                 if ( multiplePrefixes && (alreadyUsed.count(path) != 0) )
 228                     return;
 229
 230                 // if the file is mach-o, add to list
 231                 if ( addIfMachO(fileSystem, path, statBuf, requireSIP, files) ) {
 232                     if ( multiplePrefixes )
 233                         alreadyUsed.insert(path);
 234                 }
 235             });
 236         }
 237     }
 238 }
 239
 240
 241 static void findOSFilesViaBOMS(const std::vector<std::string>& pathPrefixes, bool requireSIP, std::vector<MappedMachOsByCategory>& files)
 242 {
 243     __block std::unordered_set<std::string> runtimePathsFound;
 244     for (const std::string& prefix : pathPrefixes) {
 245         iterateDirectoryTree(prefix, "/System/Library/Receipts", ^(const std::string&) { return false; }, ^(const std::string& path, const struct stat& statBuf) {
 246             if ( !contains(path, "com.apple.pkg.") )
 247                 return;
 248             if ( !endsWith(path, ".bom") )
 249                 return;
 250             std::string fullPath = prefix + path;
 251             BOMBom bom = BOMBomOpenWithSys(fullPath.c_str(), false, NULL);
 252             if ( bom == nullptr )
 253                 return;
 254             BOMFSObject rootFso = BOMBomGetRootFSObject(bom);
 255             if ( rootFso == nullptr ) {
 256                 BOMBomFree(bom);
 257                 return;
 258             }
 259             BOMBomEnumerator e = BOMBomEnumeratorNew(bom, rootFso);
 260             if ( e == nullptr ) {
 261                 fprintf(stderr, "Can't get enumerator for BOM root FSObject\n");
 262                 return;
 263             }
 264             BOMFSObjectFree(rootFso);
 265             //fprintf(stderr, "using BOM %s\n", path.c_str());
 266             while (BOMFSObject fso = BOMBomEnumeratorNext(e)) {
 267                 if ( BOMFSObjectIsBinaryObject(fso) ) {
 268                     const char* runPath = BOMFSObjectPathName(fso);
 269                     if ( (runPath[0] == '.') && (runPath[1] == '/') )
 270                         ++runPath;
 271                     if ( runtimePathsFound.count(runPath) == 0 ) {
 272                         // only add files from sAllowedPrefixes and not in sDontUsePrefixes
 273                         bool inSearchDir = false;
 274                         for (const char* searchDir : sAllowedPrefixes ) {
 275                             if ( strncmp(searchDir, runPath, strlen(searchDir)) == 0 )  {
 276                                 inSearchDir = true;
 277                                 break;
 278                             }
 279                         }
 280                         if ( inSearchDir ) {
 281                             bool inSkipDir = false;
 282                             for (const char* skipDir : sDontUsePrefixes) {
 283                                 if ( strncmp(skipDir, runPath, strlen(skipDir)) == 0 )  {
 284                                     inSkipDir = true;
 285                                     break;
 286                                 }
 287                             }
 288                             if ( !inSkipDir ) {
 289                                 for (const std::string& prefix2 : pathPrefixes) {
 290                                     struct stat statBuf2;
 291                                     std::string fullPath2 = prefix2 + runPath;
 292                                     if ( stat(fullPath2.c_str(), &statBuf2) == 0 ) {
 293                                         dyld3::closure::FileSystemPhysical fileSystem(prefix2.c_str());
 294                                         addIfMachO(fileSystem, runPath, statBuf2, requireSIP, files);
 295                                         runtimePathsFound.insert(runPath);
 296                                         break;
 297                                     }
 298                                 }
 299                             }
 300                         }
 301                     }
 302                 }
 303                 BOMFSObjectFree(fso);
 304             }
 305
 306             BOMBomEnumeratorFree(e);
 307             BOMBomFree(bom);
 308         });
 309     }
 310 }
 311
 312
 313 static bool dontCache(const std::string& volumePrefix, const std::string& archName,
 314                       const std::unordered_set<std::string>& pathsWithDuplicateInstallName,
 315                       const DyldSharedCache::MappedMachO& aFile, bool warn,
 316                       const std::unordered_set<std::string>& skipDylibs)
 317 {
 318     if ( skipDylibs.count(aFile.runtimePath) )
 319         return true;
 320     if ( startsWith(aFile.runtimePath, "/usr/lib/system/introspection/") )
 321         return true;
 322     if ( startsWith(aFile.runtimePath, "/System/Library/QuickTime/") )
 323         return true;
 324     if ( startsWith(aFile.runtimePath, "/System/Library/Tcl/") )
 325         return true;
 326     if ( startsWith(aFile.runtimePath, "/System/Library/Perl/") )
 327         return true;
 328     if ( startsWith(aFile.runtimePath, "/System/Library/MonitorPanels/") )
 329         return true;
 330     if ( startsWith(aFile.runtimePath, "/System/Library/Accessibility/") )
 331         return true;
 332     if ( startsWith(aFile.runtimePath, "/usr/local/") )
 333         return true;
 334
 335     // anything inside a .app bundle is specific to app, so should not be in shared cache
 336     if ( aFile.runtimePath.find(".app/") != std::string::npos )
 337         return true;
 338
 339     if ( archName == "i386" ) {
 340         if ( startsWith(aFile.runtimePath, "/System/Library/CoreServices/") )
 341             return true;
 342         if ( startsWith(aFile.runtimePath, "/System/Library/Extensions/") )
 343             return true;
 344     }
 345
 346     if ( aFile.runtimePath.find("//") != std::string::npos ) {
 347         if (warn) fprintf(stderr, "update_dyld_shared_cache: warning: %s skipping because of bad install name %s\n", archName.c_str(), aFile.runtimePath.c_str());
 348         return true;
 349     }
 350
 351     const char* installName = aFile.mh->installName();
 352     if ( (pathsWithDuplicateInstallName.count(aFile.runtimePath) != 0) && (aFile.runtimePath != installName) ) {
 353         if (warn) fprintf(stderr, "update_dyld_shared_cache: warning: %s skipping because of duplicate install name %s\n", archName.c_str(), aFile.runtimePath.c_str());
 354         return true;
 355     }
 356
 357     if ( aFile.runtimePath != installName ) {
 358         // see if install name is a symlink to actual path
 359         std::string fullInstall = volumePrefix + installName;
 360         char resolvedPath[PATH_MAX];
 361         if ( realpath(fullInstall.c_str(), resolvedPath) != NULL ) {
 362             std::string resolvedSymlink = resolvedPath;
 363             if ( !volumePrefix.empty() ) {
 364                 resolvedSymlink = resolvedSymlink.substr(volumePrefix.size());
 365             }
 366             if ( aFile.runtimePath == resolvedSymlink ) {
 367                 return false;
 368             }
 369         }
 370         // <rdar://problem/38000411> also if runtime path is a symlink to install name
 371         std::string fullRuntime = volumePrefix + aFile.runtimePath;
 372         if ( realpath(fullRuntime.c_str(), resolvedPath) != NULL ) {
 373             std::string resolvedSymlink = resolvedPath;
 374             if ( !volumePrefix.empty() ) {
 375                 resolvedSymlink = resolvedSymlink.substr(volumePrefix.size());
 376             }
 377             if ( resolvedSymlink == installName ) {
 378                 return false;
 379             }
 380         }
 381         if (warn) fprintf(stderr, "update_dyld_shared_cache: warning: %s skipping because of bad install name %s\n", archName.c_str(), aFile.runtimePath.c_str());
 382         return true;
 383     }
 384     return false;
 385 }
 386
 387 static void pruneCachedDylibs(const std::string& volumePrefix, const std::unordered_set<std::string>& skipDylibs, MappedMachOsByCategory& fileSet)
 388 {
 389     std::unordered_set<std::string> pathsWithDuplicateInstallName;
 390
 391     std::unordered_map<std::string, std::string> installNameToFirstPath;
 392     for (DyldSharedCache::MappedMachO& aFile : fileSet.dylibsForCache) {
 393         const char* installName = aFile.mh->installName();
 394         auto pos = installNameToFirstPath.find(installName);
 395         if ( pos == installNameToFirstPath.end() ) {
 396             installNameToFirstPath[installName] = aFile.runtimePath;
 397         }
 398         else {
 399             pathsWithDuplicateInstallName.insert(aFile.runtimePath);
 400             pathsWithDuplicateInstallName.insert(installNameToFirstPath[installName]);
 401         }
 402     }
 403
 404     for (DyldSharedCache::MappedMachO& aFile : fileSet.dylibsForCache) {
 405         if ( dontCache(volumePrefix, fileSet.archName, pathsWithDuplicateInstallName, aFile, true, skipDylibs) )
 406             fileSet.otherDylibsAndBundles.push_back(aFile);
 407     }
 408     fileSet.dylibsForCache.erase(std::remove_if(fileSet.dylibsForCache.begin(), fileSet.dylibsForCache.end(),
 409         [&](const DyldSharedCache::MappedMachO& aFile) { return dontCache(volumePrefix, fileSet.archName, pathsWithDuplicateInstallName, aFile, false, skipDylibs); }),
 410         fileSet.dylibsForCache.end());
 411 }
 412
 413 static void pruneOtherDylibs(const std::string& volumePrefix, MappedMachOsByCategory& fileSet)
 414 {
 415     // other OS dylibs should not contain dylibs that are embedded in some .app bundle
 416     fileSet.otherDylibsAndBundles.erase(std::remove_if(fileSet.otherDylibsAndBundles.begin(), fileSet.otherDylibsAndBundles.end(),
 417                                                        [&](const DyldSharedCache::MappedMachO& aFile) { return (aFile.runtimePath.find(".app/") != std::string::npos); }),
 418                                         fileSet.otherDylibsAndBundles.end());
 419 }
 420 static void pruneExecutables(const std::string& volumePrefix, MappedMachOsByCategory& fileSet)
 421 {
 422     // don't build closures for xcode shims in /usr/bin (e.g. /usr/bin/clang) which re-exec themselves to a tool inside Xcode.app
 423     fileSet.mainExecutables.erase(std::remove_if(fileSet.mainExecutables.begin(), fileSet.mainExecutables.end(),
 424         [&](const DyldSharedCache::MappedMachO& aFile) {
 425             if ( !startsWith(aFile.runtimePath, "/usr/bin/") )
 426                 return false;
 427             __block bool isXcodeShim = false;
 428             aFile.mh->forEachDependentDylib(^(const char* loadPath, bool, bool, bool, uint32_t, uint32_t, bool &stop) {
 429                 if ( strcmp(loadPath, "/usr/lib/libxcselect.dylib") == 0 )
 430                     isXcodeShim = true;
 431             });
 432             return isXcodeShim;
 433         }), fileSet.mainExecutables.end());
 434 }
 435
 436 static bool existingCacheUpToDate(const std::string& existingCache, const std::vector<DyldSharedCache::MappedMachO>& currentDylibs)
 437 {
 438     // if no existing cache, it is not up-to-date
 439     int fd = ::open(existingCache.c_str(), O_RDONLY);
 440     if ( fd < 0 )
 441         return false;
 442
 443     // build map of found dylibs
 444     std::unordered_map<std::string, const DyldSharedCache::MappedMachO*> currentDylibMap;
 445     for (const DyldSharedCache::MappedMachO& aFile : currentDylibs) {
 446         //fprintf(stderr, "0x%0llX 0x%0llX  %s\n", aFile.inode, aFile.modTime, aFile.runtimePath.c_str());
 447         currentDylibMap[aFile.runtimePath] = &aFile;
 448     }
 449
 450     // make sure all dylibs in existing cache have same mtime and inode as found dylib
 451     __block bool foundMismatch = false;
 452     const uint64_t cacheMapLen = 0x40000000;
 453     void *p = ::mmap(NULL, cacheMapLen, PROT_READ, MAP_PRIVATE, fd, 0);
 454     if ( p != MAP_FAILED ) {
 455         const DyldSharedCache* cache = (DyldSharedCache*)p;
 456         cache->forEachImageEntry(^(const char* installName, uint64_t mTime, uint64_t inode) {
 457             bool foundMatch = false;
 458             auto pos = currentDylibMap.find(installName);
 459             if ( pos != currentDylibMap.end() ) {
 460                 const DyldSharedCache::MappedMachO* foundDylib = pos->second;
 461                 if ( (foundDylib->inode == inode) && (foundDylib->modTime == mTime) ) {
 462                     foundMatch = true;
 463                 }
 464             }
 465             if ( !foundMatch ) {
 466                 // use slow path and look for any dylib with a matching inode and mtime
 467                 bool foundSlow = false;
 468                 for (const DyldSharedCache::MappedMachO& aFile : currentDylibs) {
 469                     if ( (aFile.inode == inode) && (aFile.modTime == mTime) ) {
 470                         foundSlow = true;
 471                         break;
 472                     }
 473                 }
 474                 if ( !foundSlow ) {
 475                     foundMismatch = true;
 476                     if ( verbose )
 477                         fprintf(stderr, "rebuilding dyld cache because dylib changed: %s\n", installName);
 478                 }
 479             }
 480          });
 481         ::munmap(p, cacheMapLen);
 482     }
 483
 484     ::close(fd);
 485
 486     return !foundMismatch;
 487 }
 488
 489
 490 inline uint32_t absolutetime_to_milliseconds(uint64_t abstime)
 491 {
 492     return (uint32_t)(abstime/1000/1000);
 493 }
 494
 495 static bool runningOnHaswell()
 496 {
 497     // check system is capable of running x86_64h code
 498     struct host_basic_info  info;
 499     mach_msg_type_number_t  count    = HOST_BASIC_INFO_COUNT;
 500     mach_port_t             hostPort = mach_host_self();
 501     kern_return_t           result   = host_info(hostPort, HOST_BASIC_INFO, (host_info_t)&info, &count);
 502     mach_port_deallocate(mach_task_self(), hostPort);
 503
 504     return ( (result == KERN_SUCCESS) && (info.cpu_subtype == CPU_SUBTYPE_X86_64_H) );
 505 }
 506
 507
 508
 509 #define TERMINATE_IF_LAST_ARG( s )      \
 510     do {                                \
 511         if ( i == argc - 1 ) {          \
 512             fprintf(stderr, s );        \
 513             return 1;                   \
 514         }                               \
 515     } while ( 0 )
 516
 517 int main(int argc, const char* argv[], const char* envp[])
 518 {
 519     std::string                     rootPath;
 520     std::string                     overlayPath;
 521     std::string                     dylibListFile;
 522     bool                            universal = false;
 523     bool                            force = false;
 524     bool                            searchDisk = false;
 525     bool                            dylibsRemoved = false;
 526     std::string                     cacheDir;
 527     std::unordered_set<std::string> archStrs;
 528     std::unordered_set<std::string> skipDylibs;
 529
 530     // parse command line options
 531     for (int i = 1; i < argc; ++i) {
 532         const char* arg = argv[i];
 533         if (strcmp(arg, "-debug") == 0) {
 534             verbose = true;
 535         }
 536         else if (strcmp(arg, "-verbose") == 0) {
 537             verbose = true;
 538         }
 539         else if (strcmp(arg, "-dont_map_local_symbols") == 0) {
 540             //We are going to ignore this
 541         }
 542         else if (strcmp(arg, "-dylib_list") == 0) {
 543             TERMINATE_IF_LAST_ARG("-dylib_list missing argument");
 544             dylibListFile = argv[++i];
 545         }
 546         else if ((strcmp(arg, "-root") == 0) || (strcmp(arg, "--root") == 0)) {
 547             TERMINATE_IF_LAST_ARG("-root missing path argument\n");
 548             rootPath = argv[++i];
 549         }
 550         else if (strcmp(arg, "-overlay") == 0) {
 551             TERMINATE_IF_LAST_ARG("-overlay missing path argument\n");
 552             overlayPath = argv[++i];
 553         }
 554         else if (strcmp(arg, "-cache_dir") == 0) {
 555             TERMINATE_IF_LAST_ARG("-cache_dir missing path argument\n");
 556             cacheDir = argv[++i];
 557         }
 558         else if (strcmp(arg, "-arch") == 0) {
 559             TERMINATE_IF_LAST_ARG("-arch missing argument\n");
 560             archStrs.insert(argv[++i]);
 561         }
 562         else if (strcmp(arg, "-search_disk") == 0) {
 563             searchDisk = true;
 564         }
 565         else if (strcmp(arg, "-dylibs_removed_in_mastering") == 0) {
 566             dylibsRemoved = true;
 567         }
 568         else if (strcmp(arg, "-force") == 0) {
 569             force = true;
 570         }
 571         else if (strcmp(arg, "-sort_by_name") == 0) {
 572             //No-op, we always do this now
 573         }
 574         else if (strcmp(arg, "-universal_boot") == 0) {
 575             universal = true;
 576         }
 577         else if (strcmp(arg, "-skip") == 0) {
 578             TERMINATE_IF_LAST_ARG("-skip missing argument\n");
 579             skipDylibs.insert(argv[++i]);
 580         }
 581         else {
 582             //usage();
 583             fprintf(stderr, "update_dyld_shared_cache: unknown option: %s\n", arg);
 584             return 1;
 585         }
 586     }
 587
 588     if ( !rootPath.empty() & !overlayPath.empty() ) {
 589         fprintf(stderr, "-root and -overlay cannot be used together\n");
 590         return 1;
 591     }
 592     // canonicalize rootPath
 593     if ( !rootPath.empty() ) {
 594         char resolvedPath[PATH_MAX];
 595         if ( realpath(rootPath.c_str(), resolvedPath) != NULL ) {
 596             rootPath = resolvedPath;
 597         }
 598         // <rdar://problem/33223984> when building closures for boot volume, pathPrefixes should be empty
 599         if ( rootPath == "/" ) {
 600             rootPath = "";
 601         }
 602     }
 603     // canonicalize overlayPath
 604     if ( !overlayPath.empty() ) {
 605         char resolvedPath[PATH_MAX];
 606         if ( realpath(overlayPath.c_str(), resolvedPath) != NULL ) {
 607             overlayPath = resolvedPath;
 608         }
 609     }
 610
 611     // <rdar://problem/36362221> update_dyld_shared_cache should re-exec() itself to a newer version
 612     std::string newTool;
 613     if ( !rootPath.empty() )
 614         newTool = rootPath + "/usr/bin/update_dyld_shared_cache";
 615     else if ( !overlayPath.empty() )
 616         newTool = overlayPath + "/usr/bin/update_dyld_shared_cache";
 617     if ( !newTool.empty() ) {
 618         struct stat newToolStatBuf;
 619         if ( stat(newTool.c_str(), &newToolStatBuf) == 0 ) {
 620             char curToolPath[PATH_MAX];
 621             uint32_t curToolPathsize = PATH_MAX;
 622             int result = _NSGetExecutablePath(curToolPath, &curToolPathsize);
 623             if ( result == 0 ) {
 624                 char resolvedCurToolPath[PATH_MAX];
 625                 if ( realpath(curToolPath, resolvedCurToolPath) != NULL ) {
 626                     // don't re-exec if we are already running that tool
 627                     if ( newTool != resolvedCurToolPath ) {
 628                         execve(newTool.c_str(), (char**)argv, (char**)envp);
 629                     }
 630                 }
 631             }
 632         }
 633     }
 634
 635     //
 636     // pathPrefixes for three modes:
 637     //   1) no options: { "" }           // search only boot volume
 638     //   2) -overlay:   { overlay, "" }  // search overlay, then boot volume
 639     //   3) -root:      { root }         // search only -root volume
 640     //
 641     std::vector<std::string> pathPrefixes;
 642     if ( !overlayPath.empty() )
 643         pathPrefixes.push_back(overlayPath);
 644     pathPrefixes.push_back(rootPath);
 645
 646
 647     if ( cacheDir.empty() ) {
 648         // if -cache_dir is not specified, then write() will eventually fail if we are not running as root
 649         if ( geteuid() != 0 ) {
 650             fprintf(stderr, "update_dyld_shared_cache: must be run as root (sudo)\n");
 651             return 1;
 652         }
 653
 654         // write cache file into -root or -overlay directory, if used
 655         if ( rootPath != "/" )
 656             cacheDir = rootPath +  MACOSX_DYLD_SHARED_CACHE_DIR;
 657         else if ( !overlayPath.empty()  )
 658             cacheDir = overlayPath +  MACOSX_DYLD_SHARED_CACHE_DIR;
 659         else
 660             cacheDir = MACOSX_DYLD_SHARED_CACHE_DIR;
 661    }
 662
 663     int err = mkpath_np(cacheDir.c_str(), S_IRWXU | S_IRGRP|S_IXGRP | S_IROTH|S_IXOTH);
 664     if ( (err != 0) && (err != EEXIST) ) {
 665         fprintf(stderr, "update_dyld_shared_cache: could not access cache dir: mkpath_np(%s) failed errno=%d\n", cacheDir.c_str(), err);
 666         return 1;
 667     }
 668
 669     if ( archStrs.empty() ) {
 670         if ( universal ) {
 671             // <rdar://problem/26182089> -universal_boot should make all possible dyld caches
 672             archStrs.insert("i386");
 673             archStrs.insert("x86_64");
 674             archStrs.insert("x86_64h");
 675         }
 676         else {
 677             // just make caches for this machine
 678             archStrs.insert("i386");
 679             archStrs.insert(runningOnHaswell() ? "x86_64h" : "x86_64");
 680         }
 681     }
 682
 683     uint64_t t1 = mach_absolute_time();
 684
 685     // find all mach-o files for requested architectures
 686     bool requireDylibsBeRootlessProtected = isProtectedBySIP(cacheDir);
 687     __block std::vector<MappedMachOsByCategory> allFileSets;
 688     if ( archStrs.count("x86_64") )
 689         allFileSets.push_back({"x86_64"});
 690     if ( archStrs.count("x86_64h") )
 691         allFileSets.push_back({"x86_64h"});
 692     if ( archStrs.count("i386") )
 693         allFileSets.push_back({"i386"});
 694     if ( searchDisk )
 695         findAllFiles(pathPrefixes, requireDylibsBeRootlessProtected, allFileSets);
 696     else {
 697         std::unordered_set<std::string> runtimePathsFound;
 698         findOSFilesViaBOMS(pathPrefixes, requireDylibsBeRootlessProtected, allFileSets);
 699     }
 700
 701     // nothing in OS uses i386 dylibs, so only dylibs used by third party apps need to be in cache
 702     for (MappedMachOsByCategory& fileSet : allFileSets) {
 703         pruneCachedDylibs(rootPath, skipDylibs, fileSet);
 704         pruneOtherDylibs(rootPath, fileSet);
 705         pruneExecutables(rootPath, fileSet);
 706    }
 707
 708     uint64_t t2 = mach_absolute_time();
 709     if ( verbose ) {
 710         if ( searchDisk )
 711             fprintf(stderr, "time to scan file system and construct lists of mach-o files: %ums\n", absolutetime_to_milliseconds(t2-t1));
 712         else
 713             fprintf(stderr, "time to read BOM and construct lists of mach-o files: %ums\n", absolutetime_to_milliseconds(t2-t1));
 714     }
 715
 716     // build caches in parallel on machines with at leat 4GB of RAM
 717     uint64_t memSize = 0;
 718     size_t sz = sizeof(memSize);;
 719     bool buildInParallel = false;
 720     if ( sysctlbyname("hw.memsize", &memSize, &sz, NULL, 0) == 0 ) {
 721         if ( memSize >= 0x100000000ULL )
 722             buildInParallel = true;
 723     }
 724     dispatch_queue_t dqueue = buildInParallel ? dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0)
 725                                               : dispatch_queue_create("serial-queue", DISPATCH_QUEUE_SERIAL);
 726
 727     // build all caches
 728     __block bool cacheBuildFailure = false;
 729     __block bool wroteSomeCacheFile = false;
 730     dispatch_apply(allFileSets.size(), dqueue, ^(size_t index) {
 731         MappedMachOsByCategory& fileSet = allFileSets[index];
 732         const std::string outFile = cacheDir + "/dyld_shared_cache_" + fileSet.archName;
 733
 734         DyldSharedCache::MappedMachO (^loader)(const std::string&) = ^DyldSharedCache::MappedMachO(const std::string& runtimePath) {
 735             if ( skipDylibs.count(runtimePath) )
 736                 return DyldSharedCache::MappedMachO();
 737             for (const std::string& prefix : pathPrefixes) {
 738                 std::string fullPath = prefix + runtimePath;
 739                 struct stat statBuf;
 740                 if ( stat(fullPath.c_str(), &statBuf) == 0 ) {
 741                     dyld3::closure::FileSystemPhysical fileSystem(prefix.c_str());
 742                     char resolvedPath[PATH_MAX];
 743                     if ( realpath(fullPath.c_str(), resolvedPath) != NULL ) {
 744                         std::string resolvedSymlink = resolvedPath;
 745                         if ( !rootPath.empty() ) {
 746                             resolvedSymlink = resolvedSymlink.substr(rootPath.size());
 747                         }
 748                         if ( (runtimePath != resolvedSymlink) && !contains(runtimePath, "InputContext") ) {  //HACK remove InputContext when fixed
 749                            // path requested is a symlink path, check if real path already loaded
 750                             for (const DyldSharedCache::MappedMachO& aDylibMapping : fileSet.dylibsForCache) {
 751                                 if ( aDylibMapping.runtimePath == resolvedSymlink ) {
 752                                     if ( verbose )
 753                                         fprintf(stderr, "verifySelfContained, redirect %s to %s\n", runtimePath.c_str(), aDylibMapping.runtimePath.c_str());
 754                                     return aDylibMapping;
 755                                 }
 756                             }
 757                         }
 758                     }
 759
 760                     std::vector<MappedMachOsByCategory> mappedFiles;
 761                     mappedFiles.push_back({fileSet.archName});
 762                    if ( addIfMachO(fileSystem, runtimePath, statBuf, requireDylibsBeRootlessProtected, mappedFiles) ) {
 763                         if ( !mappedFiles.back().dylibsForCache.empty() ) {
 764                             if ( verbose )
 765                                 fprintf(stderr, "verifySelfContained, add %s\n", mappedFiles.back().dylibsForCache.back().runtimePath.c_str());
 766                             return mappedFiles.back().dylibsForCache.back();
 767                         }
 768                     }
 769                 }
 770             }
 771             return DyldSharedCache::MappedMachO();
 772         };
 773         size_t startCount = fileSet.dylibsForCache.size();
 774         std::vector<std::pair<DyldSharedCache::MappedMachO, std::set<std::string>>> excludes;
 775         DyldSharedCache::verifySelfContained(fileSet.dylibsForCache, loader, excludes);
 776         for (size_t i=startCount; i < fileSet.dylibsForCache.size(); ++i) {
 777             fprintf(stderr, "update_dyld_shared_cache: warning: %s not in .bom, but adding required dylib %s\n", fileSet.archName.c_str(), fileSet.dylibsForCache[i].runtimePath.c_str());
 778         }
 779         for (auto& exclude : excludes) {
 780             std::string reasons = "(\"";
 781             for (auto i = exclude.second.begin(); i != exclude.second.end(); ++i) {
 782                 reasons += *i;
 783                 if (i != --exclude.second.end()) {
 784                     reasons += "\", \"";
 785                 }
 786             }
 787             reasons += "\")";
 788             fprintf(stderr, "update_dyld_shared_cache: warning: %s rejected from cached dylibs: %s (%s)\n", fileSet.archName.c_str(), exclude.first.runtimePath.c_str(), reasons.c_str());
 789             fileSet.otherDylibsAndBundles.push_back(exclude.first);
 790         }
 791
 792         // check if cache is already up to date
 793         if ( !force ) {
 794             if ( existingCacheUpToDate(outFile, fileSet.dylibsForCache) )
 795                 return;
 796         }
 797
 798          // add any extra dylibs needed which were not in .bom
 799         fprintf(stderr, "update_dyld_shared_cache: %s incorporating %lu OS dylibs, tracking %lu others, building closures for %lu executables\n",
 800                         fileSet.archName.c_str(), fileSet.dylibsForCache.size(), fileSet.otherDylibsAndBundles.size(), fileSet.mainExecutables.size());
 801         //for (const DyldSharedCache::MappedMachO& aFile : fileSet.otherDylibsAndBundles) {
 802         //    fprintf(stderr, "  %s\n", aFile.runtimePath.c_str());
 803         //}
 804
 805
 806         // build cache new cache file
 807         DyldSharedCache::CreateOptions options;
 808         options.outputFilePath               = outFile;
 809         options.outputMapFilePath            = cacheDir + "/dyld_shared_cache_" + fileSet.archName + ".map";
 810         options.archName                     = fileSet.archName;
 811         options.platform                     = dyld3::Platform::macOS;
 812         options.excludeLocalSymbols          = false;
 813         options.optimizeStubs                = false;
 814         options.optimizeObjC                 = true;
 815         options.codeSigningDigestMode        = DyldSharedCache::SHA256only;
 816         options.dylibsRemovedDuringMastering = dylibsRemoved;
 817         options.inodesAreSameAsRuntime       = true;
 818         options.cacheSupportsASLR            = (fileSet.archName != "i386");
 819         options.forSimulator                 = false;
 820         options.isLocallyBuiltCache          = true;
 821         options.verbose                      = verbose;
 822         options.evictLeafDylibsOnOverflow    = true;
 823         options.pathPrefixes                 = pathPrefixes;
 824         DyldSharedCache::CreateResults results = DyldSharedCache::create(options, fileSet.dylibsForCache, fileSet.otherDylibsAndBundles, fileSet.mainExecutables);
 825
 826         // print any warnings
 827         for (const std::string& warn : results.warnings) {
 828             fprintf(stderr, "update_dyld_shared_cache: warning: %s %s\n", fileSet.archName.c_str(), warn.c_str());
 829         }
 830         if ( results.errorMessage.empty() ) {
 831             wroteSomeCacheFile = true;
 832         }
 833         else {
 834             fprintf(stderr, "update_dyld_shared_cache: %s\n", results.errorMessage.c_str());
 835             cacheBuildFailure = true;
 836         }
 837     });
 838
 839
 840     // Save off spintrace data
 841     if ( wroteSomeCacheFile ) {
 842         void* h = dlopen("/usr/lib/libdscsym.dylib", 0);
 843         if ( h != nullptr ) {
 844             typedef int (*dscym_func)(const char*);
 845             dscym_func func = (dscym_func)dlsym(h, "dscsym_save_dscsyms_for_current_caches");
 846             std::string nuggetRoot = rootPath;
 847             if ( nuggetRoot.empty() )
 848                  nuggetRoot = overlayPath;
 849             if ( nuggetRoot.empty() )
 850                  nuggetRoot = "/";
 851             (*func)(nuggetRoot.c_str());
 852         }
 853     }
 854
 855
 856     // we could unmap all input files, but tool is about to quit
 857
 858     return (cacheBuildFailure ? 1 : 0);
 859 }
 860