launch-cache/MachOLayout.hpp

   1 /* -*- mode: C++; c-basic-offset: 4; tab-width: 4 -*-
   2  *
   3  * Copyright (c) 2006-2011 Apple Inc. All rights reserved.
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   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
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  11  * http://www.opensource.apple.com/apsl/ and read it before using this
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  13  *
  14  * The Original Code and all software distributed under the License are
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  24
  25 #ifndef __MACHO_LAYOUT__
  26 #define __MACHO_LAYOUT__
  27
  28 #include <sys/types.h>
  29 #include <sys/stat.h>
  30 #include <sys/errno.h>
  31 #include <sys/mman.h>
  32 #include <mach/mach.h>
  33 #include <limits.h>
  34 #include <stdarg.h>
  35 #include <stdio.h>
  36 #include <fcntl.h>
  37 #include <errno.h>
  38 #include <unistd.h>
  39 #include <mach-o/loader.h>
  40 #include <mach-o/fat.h>
  41
  42 #include <vector>
  43 #include <set>
  44 #include <unordered_map>
  45
  46 #include "MachOFileAbstraction.hpp"
  47 #include "Architectures.hpp"
  48
  49
  50 void throwf(const char* format, ...) __attribute__((format(printf, 1, 2)));
  51
  52 __attribute__((noreturn))
  53 void throwf(const char* format, ...)
  54 {
  55         va_list list;
  56         char*   p;
  57         va_start(list, format);
  58         vasprintf(&p, format, list);
  59         va_end(list);
  60
  61         const char*     t = p;
  62         throw t;
  63 }
  64
  65
  66 class MachOLayoutAbstraction
  67 {
  68 public:
  69         struct Segment
  70         {
  71         public:
  72                                         Segment(uint64_t addr, uint64_t vmsize, uint64_t offset, uint64_t file_size, uint64_t align,
  73                                                         uint32_t prot, const char* segName) : fOrigAddress(addr), fOrigSize(vmsize),
  74                                                         fOrigFileOffset(offset),  fOrigFileSize(file_size), fOrigPermissions(prot),
  75                                                         fSize(vmsize), fFileOffset(offset), fFileSize(file_size), fAlignment(align),
  76                                                         fPermissions(prot), fNewAddress(0), fMappedAddress(NULL) {
  77                                                                 strlcpy(fOrigName, segName, 16);
  78                                                         }
  79
  80                 uint64_t        address() const         { return fOrigAddress; }
  81                 uint64_t        size() const            { return fSize; }
  82                 uint64_t        fileOffset() const      { return fFileOffset; }
  83                 uint64_t        fileSize() const        { return fFileSize; }
  84                 uint32_t        permissions() const { return fPermissions; }
  85                 bool            readable() const        { return fPermissions & VM_PROT_READ; }
  86                 bool            writable() const        { return fPermissions & VM_PROT_WRITE; }
  87                 bool            executable() const      { return fPermissions & VM_PROT_EXECUTE; }
  88                 uint64_t        alignment() const       { return fAlignment; }
  89                 const char* name() const                { return fOrigName; }
  90                 uint64_t        newAddress() const      { return fNewAddress; }
  91                 void*           mappedAddress() const                   { return fMappedAddress; }
  92                 void            setNewAddress(uint64_t addr)    { fNewAddress = addr; }
  93                 void            setMappedAddress(void* addr)    { fMappedAddress = addr; }
  94                 void            setSize(uint64_t new_size)              { fSize = new_size; }
  95                 void            setFileOffset(uint64_t new_off) { fFileOffset = new_off; }
  96                 void            setFileSize(uint64_t new_size)  { fFileSize = new_size; }
  97                 void            setWritable(bool w)                             { if (w) fPermissions |= VM_PROT_WRITE; else fPermissions &= ~VM_PROT_WRITE; }
  98                 void            reset()                                                 { fSize=fOrigSize; fFileOffset=fOrigFileOffset; fFileSize=fOrigFileSize; fPermissions=fOrigPermissions; }
  99         private:
 100                 uint64_t                fOrigAddress;
 101                 uint64_t                fOrigSize;
 102                 uint64_t                fOrigFileOffset;
 103                 uint64_t                fOrigFileSize;
 104                 uint32_t                fOrigPermissions;
 105                 char                    fOrigName[16];
 106                 uint64_t                fSize;
 107                 uint64_t                fFileOffset;
 108                 uint64_t                fFileSize;
 109                 uint64_t                fAlignment;
 110                 uint32_t                fPermissions;
 111                 uint64_t                fNewAddress;
 112                 void*                   fMappedAddress;
 113         };
 114
 115         struct Library
 116         {
 117                 const char*     name;
 118                 uint32_t        currentVersion;
 119                 uint32_t        compatibilityVersion;
 120                 bool            weakImport;
 121         };
 122
 123
 124         virtual ArchPair                                                        getArchPair() const = 0;
 125         virtual const char*                                                     getFilePath() const = 0;
 126         virtual uint64_t                                                        getOffsetInUniversalFile() const        = 0;
 127         virtual uint32_t                                                        getFileType() const     = 0;
 128         virtual uint32_t                                                        getFlags() const = 0;
 129         virtual Library                                                         getID() const = 0;
 130         virtual bool                                                            isDylib() const = 0;
 131         virtual bool                                                            isSplitSeg() const = 0;
 132         virtual bool                                                            hasSplitSegInfo() const = 0;
 133         virtual bool                                                            isRootOwned() const = 0;
 134         virtual bool                                                            inSharableLocation() const = 0;
 135         virtual bool                                                            hasDynamicLookupLinkage() const = 0;
 136         virtual bool                                                            hasMainExecutableLookupLinkage() const = 0;
 137         virtual bool                                                            isTwoLevelNamespace() const     = 0;
 138         virtual bool                                                            hasDyldInfo() const     = 0;
 139         virtual bool                                                            hasMultipleReadWriteSegments() const = 0;
 140         virtual uint32_t                                                        getNameFileOffset() const = 0;
 141         virtual time_t                                                          getLastModTime() const = 0;
 142         virtual ino_t                                                           getInode() const = 0;
 143         virtual std::vector<Segment>&                           getSegments() = 0;
 144         virtual const std::vector<Segment>&                     getSegments() const = 0;
 145         virtual const Segment*                                          getSegment(const char* name) const = 0;
 146         virtual const std::vector<Library>&                     getLibraries() const = 0;
 147         virtual uint64_t                                                        getBaseAddress() const = 0;
 148         virtual uint64_t                                                        getVMSize() const = 0;
 149         virtual uint64_t                                                        getBaseExecutableAddress() const = 0;
 150         virtual uint64_t                                                        getBaseWritableAddress() const = 0;
 151         virtual uint64_t                                                        getBaseReadOnlyAddress() const = 0;
 152         virtual uint64_t                                                        getExecutableVMSize() const = 0;
 153         virtual uint64_t                                                        getWritableVMSize() const = 0;
 154         virtual uint64_t                                                        getReadOnlyVMSize() const = 0;
 155         // need getDyldInfoExports because export info uses ULEB encoding and size could grow
 156         virtual const uint8_t*                                          getDyldInfoExports() const = 0;
 157         virtual void                                                            setDyldInfoExports(const uint8_t* newExports) const = 0;
 158         virtual void                                                            uuid(uuid_t u) const = 0;
 159 };
 160
 161
 162
 163
 164 template <typename A>
 165 class MachOLayout : public MachOLayoutAbstraction
 166 {
 167 public:
 168                                                                                                 MachOLayout(const void* machHeader, uint64_t offset, const char* path,
 169                                                                                                                                         ino_t inode, time_t modTime, uid_t uid);
 170         virtual                                                                         ~MachOLayout() {}
 171
 172         virtual ArchPair                                                        getArchPair() const             { return fArchPair; }
 173         virtual const char*                                                     getFilePath() const             { return fPath; }
 174         virtual uint64_t                                                        getOffsetInUniversalFile() const { return fOffset; }
 175         virtual uint32_t                                                        getFileType() const             { return fFileType; }
 176         virtual uint32_t                                                        getFlags() const                { return fFlags; }
 177         virtual Library                                                         getID() const                   { return fDylibID; }
 178         virtual bool                                                            isDylib() const                 { return fIsDylib; }
 179         virtual bool                                                            isSplitSeg() const;
 180         virtual bool                                                            hasSplitSegInfo() const { return fHasSplitSegInfo; }
 181         virtual bool                                                            isRootOwned() const             { return fRootOwned; }
 182         virtual bool                                                            inSharableLocation() const { return fShareableLocation; }
 183         virtual bool                                                            hasDynamicLookupLinkage() const { return fDynamicLookupLinkage; }
 184         virtual bool                                                            hasMainExecutableLookupLinkage() const { return fMainExecutableLookupLinkage; }
 185         virtual bool                                                            isTwoLevelNamespace() const     { return (fFlags & MH_TWOLEVEL); }
 186         virtual bool                                                            hasDyldInfo() const             { return fHasDyldInfo; }
 187         virtual bool                                                            hasMultipleReadWriteSegments() const { return fHasTooManyWritableSegments; }
 188         virtual uint32_t                                                        getNameFileOffset() const{ return fNameFileOffset; }
 189         virtual time_t                                                          getLastModTime() const  { return fMTime; }
 190         virtual ino_t                                                           getInode() const                { return fInode; }
 191         virtual std::vector<Segment>&                           getSegments()                   { return fSegments; }
 192         virtual const std::vector<Segment>&                     getSegments() const             { return fSegments; }
 193         virtual const Segment*                                          getSegment(const char* name) const;
 194         virtual const std::vector<Library>&                     getLibraries() const    { return fLibraries; }
 195         virtual uint64_t                                                        getBaseAddress() const  { return fLowSegment->address(); }
 196         virtual uint64_t                                                        getVMSize() const               { return fVMSize; }
 197         virtual uint64_t                                                        getBaseExecutableAddress() const { return fLowExecutableSegment->address(); }
 198         virtual uint64_t                                                        getBaseWritableAddress() const  { return fLowWritableSegment->address(); }
 199         virtual uint64_t                                                        getBaseReadOnlyAddress() const  { return fLowReadOnlySegment->address(); }
 200         virtual uint64_t                                                        getExecutableVMSize() const             { return fVMExecutableSize; }
 201         virtual uint64_t                                                        getWritableVMSize() const               { return fVMWritablSize; }
 202         virtual uint64_t                                                        getReadOnlyVMSize() const               { return fVMReadOnlySize; }
 203         virtual const uint8_t*                                          getDyldInfoExports() const              { return fDyldInfoExports; }
 204         virtual void                                                            setDyldInfoExports(const uint8_t* newExports) const { fDyldInfoExports = newExports; }
 205         virtual void                                                            uuid(uuid_t u) const { memcpy(u, fUUID, 16); }
 206
 207 private:
 208         typedef typename A::P                                   P;
 209         typedef typename A::P::E                                E;
 210         typedef typename A::P::uint_t                   pint_t;
 211
 212         uint64_t                                                                        segmentSize(const macho_segment_command<typename A::P>* segCmd) const;
 213         uint64_t                                                                        segmentFileSize(const macho_segment_command<typename A::P>* segCmd) const;
 214         uint64_t                                                                        segmentAlignment(const macho_segment_command<typename A::P>* segCmd) const;
 215         bool                                                                            validReadWriteSeg(const Segment& seg) const;
 216
 217         static cpu_type_t                                                       arch();
 218
 219         const char*                                                                     fPath;
 220         uint64_t                                                                        fOffset;
 221         uint32_t                                                                        fFileType;
 222         ArchPair                                                                        fArchPair;
 223         uint32_t                                                                        fFlags;
 224         std::vector<Segment>                                            fSegments;
 225         std::vector<Library>                                            fLibraries;
 226         const Segment*                                                          fLowSegment;
 227         const Segment*                                                          fLowExecutableSegment;
 228         const Segment*                                                          fLowWritableSegment;
 229         const Segment*                                                          fLowReadOnlySegment;
 230         Library                                                                         fDylibID;
 231         uint32_t                                                                        fNameFileOffset;
 232         time_t                                                                          fMTime;
 233         ino_t                                                                           fInode;
 234         uint64_t                                                                        fVMSize;
 235         uint64_t                                                                        fVMExecutableSize;
 236         uint64_t                                                                        fVMWritablSize;
 237         uint64_t                                                                        fVMReadOnlySize;
 238         bool                                                                            fHasSplitSegInfo;
 239         bool                                                                            fRootOwned;
 240         bool                                                                            fShareableLocation;
 241         bool                                                                            fDynamicLookupLinkage;
 242         bool                                                                            fMainExecutableLookupLinkage;
 243         bool                                                                            fIsDylib;
 244         bool                                                                            fHasDyldInfo;
 245         bool                                                                            fHasTooManyWritableSegments;
 246         mutable const uint8_t*                                          fDyldInfoExports;
 247         uuid_t                                                                          fUUID;
 248 };
 249
 250
 251
 252 class UniversalMachOLayout
 253 {
 254 public:
 255                                                                                                 UniversalMachOLayout(const char* path, const std::set<ArchPair>* onlyArchs=NULL);
 256                                                                                                 ~UniversalMachOLayout() {}
 257
 258         static const UniversalMachOLayout&                      find(const char* path, const std::set<ArchPair>* onlyArchs=NULL);
 259         const MachOLayoutAbstraction*                           getSlice(ArchPair ap) const;
 260         const std::vector<MachOLayoutAbstraction*>&     allLayouts() const { return fLayouts; }
 261
 262 private:
 263         class CStringHash {
 264         public:
 265                 size_t operator()(const char* __s) const {
 266                         size_t __h = 0;
 267                         for ( ; *__s; ++__s)
 268                                 __h = 5 * __h + *__s;
 269                         return __h;
 270                 };
 271         };
 272         struct CStringEquals {
 273                 bool operator()(const char* left, const char* right) const { return (strcmp(left, right) == 0); }
 274         };
 275         typedef std::unordered_map<const char*, const UniversalMachOLayout*, CStringHash, CStringEquals> PathToNode;
 276
 277         static bool                                     requestedSlice(const std::set<ArchPair>* onlyArchs, cpu_type_t cpuType, cpu_subtype_t cpuSubType);
 278
 279         static PathToNode                                                       fgLayoutCache;
 280         const char*                                                                     fPath;
 281         std::vector<MachOLayoutAbstraction*>            fLayouts;
 282 };
 283
 284 UniversalMachOLayout::PathToNode UniversalMachOLayout::fgLayoutCache;
 285
 286
 287
 288
 289 const MachOLayoutAbstraction* UniversalMachOLayout::getSlice(ArchPair ap) const
 290 {
 291         // use matching cputype and cpusubtype
 292         for(std::vector<MachOLayoutAbstraction*>::const_iterator it=fLayouts.begin(); it != fLayouts.end(); ++it) {
 293                 const MachOLayoutAbstraction* layout = *it;
 294                 if ( layout->getArchPair().arch == ap.arch ) {
 295             switch ( ap.arch ) {
 296                 case CPU_TYPE_ARM:
 297                                 case CPU_TYPE_X86_64:
 298                    if ( (layout->getArchPair().subtype & ~CPU_SUBTYPE_MASK) == (ap.subtype & ~CPU_SUBTYPE_MASK) )
 299                         return layout;
 300                     break;
 301                  default:
 302                     return layout;
 303             }
 304         }
 305         }
 306         // if requesting x86_64h and it did not exist, try x86_64 as a fallback
 307         if ((ap.arch == CPU_TYPE_X86_64) && (ap.subtype == CPU_SUBTYPE_X86_64_H)) {
 308                 ap.subtype = CPU_SUBTYPE_X86_64_ALL;
 309                 return this->getSlice(ap);
 310         }
 311         return NULL;
 312 }
 313
 314
 315 const UniversalMachOLayout& UniversalMachOLayout::find(const char* path, const std::set<ArchPair>* onlyArchs)
 316 {
 317         // look in cache
 318         PathToNode::iterator pos = fgLayoutCache.find(path);
 319         if ( pos != fgLayoutCache.end() )
 320                 return *pos->second;
 321
 322         // create UniversalMachOLayout
 323         const UniversalMachOLayout* result = new UniversalMachOLayout(path, onlyArchs);
 324
 325         // add it to cache
 326         fgLayoutCache[result->fPath] = result;
 327
 328         return *result;
 329 }
 330
 331
 332 bool UniversalMachOLayout::requestedSlice(const std::set<ArchPair>* onlyArchs, cpu_type_t cpuType, cpu_subtype_t cpuSubType)
 333 {
 334         if ( onlyArchs == NULL )
 335                 return true;
 336         // must match cputype and cpusubtype
 337         for (std::set<ArchPair>::const_iterator it = onlyArchs->begin(); it != onlyArchs->end(); ++it) {
 338                 ArchPair anArch = *it;
 339                 if ( cpuType == anArch.arch ) {
 340             switch ( cpuType ) {
 341                 case CPU_TYPE_ARM:
 342                     if ( cpuSubType == anArch.subtype )
 343                         return true;
 344                     break;
 345                 default:
 346                     return true;
 347             }
 348         }
 349         }
 350         return false;
 351 }
 352
 353
 354 UniversalMachOLayout::UniversalMachOLayout(const char* path, const std::set<ArchPair>* onlyArchs)
 355  : fPath(strdup(path))
 356 {
 357         // map in whole file
 358         int fd = ::open(path, O_RDONLY, 0);
 359         if ( fd == -1 ) {
 360                 int err = errno;
 361                 if  ( err == ENOENT )
 362                         throwf("file not found");
 363                 else
 364                         throwf("can't open file, errno=%d", err);
 365         }
 366         struct stat stat_buf;
 367         if ( fstat(fd, &stat_buf) == -1)
 368                 throwf("can't stat open file %s, errno=%d", path, errno);
 369         if ( stat_buf.st_size < 20 )
 370                 throwf("file too small %s", path);
 371         uint8_t* p = (uint8_t*)::mmap(NULL, stat_buf.st_size, PROT_READ, MAP_FILE | MAP_PRIVATE, fd, 0);
 372         if ( p == (uint8_t*)(-1) )
 373                 throwf("can't map file %s, errno=%d", path, errno);
 374         ::close(fd);
 375
 376         try {
 377                 // if fat file, process each architecture
 378                 const fat_header* fh = (fat_header*)p;
 379                 const mach_header* mh = (mach_header*)p;
 380                 if ( fh->magic == OSSwapBigToHostInt32(FAT_MAGIC) ) {
 381                         // Fat header is always big-endian
 382                         const struct fat_arch* slices = (struct fat_arch*)(p + sizeof(struct fat_header));
 383                         const uint32_t sliceCount = OSSwapBigToHostInt32(fh->nfat_arch);
 384                         for (uint32_t i=0; i < sliceCount; ++i) {
 385                                 if ( requestedSlice(onlyArchs, OSSwapBigToHostInt32(slices[i].cputype), OSSwapBigToHostInt32(slices[i].cpusubtype)) ) {
 386                                         uint32_t fileOffset = OSSwapBigToHostInt32(slices[i].offset);
 387                                         if ( fileOffset > stat_buf.st_size ) {
 388                                                 throwf("malformed universal file, slice %u for architecture 0x%08X is beyond end of file: %s",
 389                                                                 i, OSSwapBigToHostInt32(slices[i].cputype), path);
 390                                         }
 391                                         if ( (fileOffset+OSSwapBigToHostInt32(slices[i].size)) > stat_buf.st_size ) {
 392                                                 throwf("malformed universal file, slice %u for architecture 0x%08X is beyond end of file: %s",
 393                                                                 i, OSSwapBigToHostInt32(slices[i].cputype), path);
 394                                         }
 395                                         try {
 396                                                 switch ( OSSwapBigToHostInt32(slices[i].cputype) ) {
 397                                                         case CPU_TYPE_I386:
 398                                                                 fLayouts.push_back(new MachOLayout<x86>(&p[fileOffset], fileOffset, fPath, stat_buf.st_ino, stat_buf.st_mtime, stat_buf.st_uid));
 399                                                                 break;
 400                                                         case CPU_TYPE_X86_64:
 401                                                                 fLayouts.push_back(new MachOLayout<x86_64>(&p[fileOffset], fileOffset, fPath, stat_buf.st_ino, stat_buf.st_mtime, stat_buf.st_uid));
 402                                                                 break;
 403                                                         case CPU_TYPE_ARM:
 404                                                                 fLayouts.push_back(new MachOLayout<arm>(&p[fileOffset], fileOffset, fPath, stat_buf.st_ino, stat_buf.st_mtime, stat_buf.st_uid));
 405                                                                 break;
 406                                                         case CPU_TYPE_ARM64:
 407                                                                 fLayouts.push_back(new MachOLayout<arm64>(&p[fileOffset], fileOffset, fPath, stat_buf.st_ino, stat_buf.st_mtime, stat_buf.st_uid));
 408                                                                 break;
 409                                                         default:
 410                                                                 throw "unknown slice in fat file";
 411                                                 }
 412                                         }
 413                                         catch (const char* msg) {
 414                                                 fprintf(stderr, "warning: %s for %s\n", msg, path);
 415                                         }
 416                                 }
 417                         }
 418                 }
 419                 else {
 420                         try {
 421                                 if ( (OSSwapLittleToHostInt32(mh->magic) == MH_MAGIC) && (OSSwapLittleToHostInt32(mh->cputype) == CPU_TYPE_I386)) {
 422                                         if ( requestedSlice(onlyArchs, OSSwapLittleToHostInt32(mh->cputype), OSSwapLittleToHostInt32(mh->cpusubtype)) )
 423                                                 fLayouts.push_back(new MachOLayout<x86>(mh, 0, fPath, stat_buf.st_ino, stat_buf.st_mtime, stat_buf.st_uid));
 424                                 }
 425                                 else if ( (OSSwapLittleToHostInt32(mh->magic) == MH_MAGIC_64) && (OSSwapLittleToHostInt32(mh->cputype) == CPU_TYPE_X86_64)) {
 426                                         if ( requestedSlice(onlyArchs, OSSwapLittleToHostInt32(mh->cputype), OSSwapLittleToHostInt32(mh->cpusubtype)) )
 427                                                 fLayouts.push_back(new MachOLayout<x86_64>(mh, 0, fPath, stat_buf.st_ino, stat_buf.st_mtime, stat_buf.st_uid));
 428                                 }
 429                                 else if ( (OSSwapLittleToHostInt32(mh->magic) == MH_MAGIC) && (OSSwapLittleToHostInt32(mh->cputype) == CPU_TYPE_ARM)) {
 430                                         if ( requestedSlice(onlyArchs, OSSwapLittleToHostInt32(mh->cputype), OSSwapLittleToHostInt32(mh->cpusubtype)) )
 431                                                 fLayouts.push_back(new MachOLayout<arm>(mh, 0, fPath, stat_buf.st_ino, stat_buf.st_mtime, stat_buf.st_uid));
 432                                 }
 433                                 else if ( (OSSwapLittleToHostInt32(mh->magic) == MH_MAGIC_64) && (OSSwapLittleToHostInt32(mh->cputype) == CPU_TYPE_ARM64)) {
 434                                         if ( requestedSlice(onlyArchs, OSSwapLittleToHostInt32(mh->cputype), OSSwapLittleToHostInt32(mh->cpusubtype)) )
 435                                                 fLayouts.push_back(new MachOLayout<arm64>(mh, 0, fPath, stat_buf.st_ino, stat_buf.st_mtime, stat_buf.st_uid));
 436                                 }
 437                                 else {
 438                                         throw "unknown file format";
 439                                 }
 440                         }
 441                         catch (const char* msg) {
 442                                 fprintf(stderr, "warning: %s for %s\n", msg, path);
 443                         }
 444                 }
 445         }
 446         catch (...) {
 447                 ::munmap(p, stat_buf.st_size);
 448                 throw;
 449         }
 450 }
 451
 452
 453 template <typename A>
 454 uint64_t MachOLayout<A>::segmentSize(const macho_segment_command<typename A::P>* segCmd) const
 455 {
 456         // <rdar://problem/13089366> segments may have 16KB alignment padding at end, if so we can remove that in cache
 457         if ( segCmd->nsects() > 0 ) {
 458                 const macho_section<P>* const sectionsStart = (macho_section<P>*)((uint8_t*)segCmd + sizeof(macho_segment_command<P>));
 459                 const macho_section<P>* const lastSection = &sectionsStart[segCmd->nsects()-1];
 460                 uint64_t endSectAddr = lastSection->addr() + lastSection->size();
 461                 uint64_t endSectAddrPage = (endSectAddr + 4095) & (-4096);
 462                 if ( endSectAddrPage < (segCmd->vmaddr() + segCmd->vmsize()) ) {
 463                         uint64_t size =  endSectAddrPage - segCmd->vmaddr();
 464                         //if ( size != segCmd->vmsize() )
 465                         //      fprintf(stderr, "trim %s size=0x%08llX instead of 0x%08llX for %s\n",
 466                         //              segCmd->segname(), size, segCmd->vmsize(), getFilePath());
 467                         return size;
 468                 }
 469         }
 470         return segCmd->vmsize();
 471 }
 472
 473 template <typename A>
 474 uint64_t MachOLayout<A>::segmentAlignment(const macho_segment_command<typename A::P>* segCmd) const
 475 {
 476         int p2align = 12;
 477         if ( segCmd->nsects() > 0 ) {
 478                 const macho_section<P>* const sectionsStart = (macho_section<P>*)((uint8_t*)segCmd + sizeof(macho_segment_command<P>));
 479                 const macho_section<P>* const sectionsEnd = &sectionsStart[segCmd->nsects()-1];
 480                 for (const macho_section<P>*  sect=sectionsStart; sect < sectionsEnd; ++sect) {
 481                         if ( sect->align() > p2align )
 482                                 p2align = sect->align();
 483                 }
 484         }
 485         return (1 << p2align);
 486 }
 487
 488 template <typename A>
 489 uint64_t MachOLayout<A>::segmentFileSize(const macho_segment_command<typename A::P>* segCmd) const
 490 {
 491         // <rdar://problem/13089366> segments may have 16KB alignment padding at end, if so we can remove that in cache
 492         if ( segCmd->nsects() > 0 ) {
 493                 uint64_t endOffset = segCmd->fileoff();
 494                 const macho_section<P>* const sectionsStart = (macho_section<P>*)((uint8_t*)segCmd + sizeof(macho_segment_command<P>));
 495                 const macho_section<P>* const sectionsEnd = &sectionsStart[segCmd->nsects()];
 496                 for (const macho_section<P>* sect=sectionsStart; sect < sectionsEnd; ++sect) {
 497                         if ( sect->offset() != 0 )
 498                                 endOffset = sect->offset() + sect->size();
 499                 }
 500                 uint64_t size = (endOffset - segCmd->fileoff() + 4095) & (-4096);
 501                 //if ( size != segCmd->filesize() )
 502                 //      fprintf(stderr, "trim %s filesize=0x%08llX instead of 0x%08llX for %s\n",
 503                 //              segCmd->segname(), size, segCmd->filesize(), getFilePath());
 504                 return size;
 505         }
 506         return segCmd->filesize();
 507 }
 508
 509
 510 template <typename A>
 511 MachOLayout<A>::MachOLayout(const void* machHeader, uint64_t offset, const char* path, ino_t inode, time_t modTime, uid_t uid)
 512  : fPath(path), fOffset(offset), fArchPair(0,0), fMTime(modTime), fInode(inode), fHasSplitSegInfo(false), fRootOwned(uid==0),
 513    fShareableLocation(false), fDynamicLookupLinkage(false), fMainExecutableLookupLinkage(false), fIsDylib(false),
 514         fHasDyldInfo(false), fHasTooManyWritableSegments(false), fDyldInfoExports(NULL)
 515 {
 516         fDylibID.name = NULL;
 517         fDylibID.currentVersion = 0;
 518         fDylibID.compatibilityVersion = 0;
 519         bzero(fUUID, sizeof(fUUID));
 520
 521         const macho_header<P>* mh = (const macho_header<P>*)machHeader;
 522         if ( mh->cputype() != arch() )
 523                 throw "Layout object is wrong architecture";
 524         switch ( mh->filetype() ) {
 525                 case MH_DYLIB:
 526                         fIsDylib = true;
 527                         break;
 528                 case MH_BUNDLE:
 529                 case MH_EXECUTE:
 530                 case MH_DYLIB_STUB:
 531                 case MH_DYLINKER:
 532                         break;
 533                 default:
 534                         throw "file is not a mach-o final linked image";
 535         }
 536         fFlags = mh->flags();
 537         fFileType = mh->filetype();
 538         fArchPair.arch = mh->cputype();
 539         fArchPair.subtype = mh->cpusubtype();
 540
 541         const macho_dyld_info_command<P>* dyldInfo = NULL;
 542         const macho_symtab_command<P>* symbolTableCmd = NULL;
 543         const macho_dysymtab_command<P>* dynamicSymbolTableCmd = NULL;
 544         const macho_load_command<P>* const cmds = (macho_load_command<P>*)((uint8_t*)mh + sizeof(macho_header<P>));
 545         const uint32_t cmd_count = mh->ncmds();
 546         const macho_load_command<P>* cmd = cmds;
 547         for (uint32_t i = 0; i < cmd_count; ++i) {
 548                 switch ( cmd->cmd() ) {
 549                         case LC_ID_DYLIB:
 550                                 {
 551                                         macho_dylib_command<P>* dylib  = (macho_dylib_command<P>*)cmd;
 552                                         fDylibID.name = strdup(dylib->name());
 553                                         fDylibID.currentVersion = dylib->current_version();
 554                                         fDylibID.compatibilityVersion = dylib->compatibility_version();
 555                                         fNameFileOffset = dylib->name() - (char*)machHeader;
 556                                         fShareableLocation = ( (strncmp(fDylibID.name, "/usr/lib/", 9) == 0) || (strncmp(fDylibID.name, "/System/Library/", 16) == 0) );
 557                                 }
 558                                 break;
 559                         case LC_LOAD_DYLIB:
 560                         case LC_LOAD_WEAK_DYLIB:
 561                         case LC_REEXPORT_DYLIB:
 562                         case LC_LOAD_UPWARD_DYLIB:
 563                                 {
 564                                         macho_dylib_command<P>* dylib = (macho_dylib_command<P>*)cmd;
 565                                         Library lib;
 566                                         lib.name = strdup(dylib->name());
 567                                         lib.currentVersion = dylib->current_version();
 568                                         lib.compatibilityVersion = dylib->compatibility_version();
 569                                         lib.weakImport = ( cmd->cmd() == LC_LOAD_WEAK_DYLIB );
 570                                         fLibraries.push_back(lib);
 571                                 }
 572                                 break;
 573                         case LC_SEGMENT_SPLIT_INFO:
 574                                 fHasSplitSegInfo = true;
 575                                 break;
 576                         case macho_segment_command<P>::CMD:
 577                                 {
 578                                         const macho_segment_command<P>* segCmd = (macho_segment_command<P>*)cmd;
 579                                         fSegments.push_back(Segment(segCmd->vmaddr(), segmentSize(segCmd), segCmd->fileoff(),
 580                                                                 segmentFileSize(segCmd), segmentAlignment(segCmd), segCmd->initprot(), segCmd->segname()));
 581                                 }
 582                                 break;
 583                         case LC_SYMTAB:
 584                                 symbolTableCmd = (macho_symtab_command<P>*)cmd;
 585                                 break;
 586                         case LC_DYSYMTAB:
 587                                 dynamicSymbolTableCmd = (macho_dysymtab_command<P>*)cmd;
 588                                 break;
 589                         case LC_DYLD_INFO:
 590                         case LC_DYLD_INFO_ONLY:
 591                                 fHasDyldInfo = true;
 592                                 dyldInfo = (struct macho_dyld_info_command<P>*)cmd;
 593                                 break;
 594                         case LC_UUID:
 595                                 {
 596                                         const macho_uuid_command<P>* uc = (macho_uuid_command<P>*)cmd;
 597                                         memcpy(&fUUID, uc->uuid(), 16);
 598                                 }
 599                                 break;
 600                 }
 601                 cmd = (const macho_load_command<P>*)(((uint8_t*)cmd)+cmd->cmdsize());
 602         }
 603
 604         fLowSegment = NULL;
 605         fLowExecutableSegment = NULL;
 606         fLowWritableSegment = NULL;
 607         fLowReadOnlySegment = NULL;
 608         fVMExecutableSize = 0;
 609         fVMWritablSize = 0;
 610         fVMReadOnlySize = 0;
 611         fVMSize = 0;
 612         const Segment* highSegment = NULL;
 613         for(std::vector<Segment>::const_iterator it = fSegments.begin(); it != fSegments.end(); ++it) {
 614                 const Segment& seg = *it;
 615                 if ( (fLowSegment == NULL) || (seg.address() < fLowSegment->address()) )
 616                         fLowSegment = &seg;
 617                 if ( (highSegment == NULL) || (seg.address() > highSegment->address()) )
 618                         highSegment = &seg;
 619                 if ( seg.executable() ) {
 620                         if ( (fLowExecutableSegment == NULL) || (seg.address() < fLowExecutableSegment->address()) )
 621                                 fLowExecutableSegment = &seg;
 622                         fVMExecutableSize += seg.size();
 623                 }
 624                 else if ( seg.writable()) {
 625                         if ( (fLowWritableSegment == NULL) || (seg.address() < fLowWritableSegment->address()) )
 626                                 fLowWritableSegment = &seg;
 627                         fVMWritablSize += seg.size();
 628                         if ( !validReadWriteSeg(seg) ) {
 629                                 fHasTooManyWritableSegments = true;
 630                         }
 631                 }
 632                 else {
 633                         if ( (fLowReadOnlySegment == NULL) || (seg.address() < fLowReadOnlySegment->address()) )
 634                                 fLowReadOnlySegment = &seg;
 635                         fVMReadOnlySize += seg.size();
 636                 }
 637         }
 638         if ( (highSegment != NULL) && (fLowSegment != NULL) )
 639                 fVMSize = (highSegment->address() + highSegment->size() - fLowSegment->address() + 4095) & (-4096);
 640
 641         // scan undefines looking, for magic ordinals
 642         if ( (symbolTableCmd != NULL) && (dynamicSymbolTableCmd != NULL) ) {
 643                 const macho_nlist<P>* symbolTable = (macho_nlist<P>*)((uint8_t*)machHeader + symbolTableCmd->symoff());
 644                 const uint32_t startUndefs = dynamicSymbolTableCmd->iundefsym();
 645                 const uint32_t endUndefs = startUndefs + dynamicSymbolTableCmd->nundefsym();
 646                 for (uint32_t i=startUndefs; i < endUndefs; ++i) {
 647                         uint8_t ordinal = GET_LIBRARY_ORDINAL(symbolTable[i].n_desc());
 648                         if ( ordinal == DYNAMIC_LOOKUP_ORDINAL )
 649                                 fDynamicLookupLinkage = true;
 650                         else if ( ordinal == EXECUTABLE_ORDINAL )
 651                                 fMainExecutableLookupLinkage = true;
 652                 }
 653         }
 654
 655         if ( dyldInfo != NULL ) {
 656                 if ( dyldInfo->export_off() != 0 ) {
 657                         fDyldInfoExports = (uint8_t*)machHeader + dyldInfo->export_off();
 658                 }
 659         }
 660
 661 }
 662
 663 template <> cpu_type_t MachOLayout<x86>::arch()     { return CPU_TYPE_I386; }
 664 template <> cpu_type_t MachOLayout<x86_64>::arch()  { return CPU_TYPE_X86_64; }
 665 template <> cpu_type_t MachOLayout<arm>::arch()         { return CPU_TYPE_ARM; }
 666 template <> cpu_type_t MachOLayout<arm64>::arch()       { return CPU_TYPE_ARM64; }
 667
 668 template <>
 669 bool MachOLayout<x86>::validReadWriteSeg(const Segment& seg) const
 670 {
 671         return (strcmp(seg.name(), "__DATA") == 0) || (strcmp(seg.name(), "__OBJC") == 0);
 672 }
 673
 674 template <typename A>
 675 bool MachOLayout<A>::validReadWriteSeg(const Segment& seg) const
 676 {
 677         return (strcmp(seg.name(), "__DATA") == 0);
 678 }
 679
 680
 681 template <>
 682 bool MachOLayout<x86>::isSplitSeg() const
 683 {
 684         return ( (this->getFlags() & MH_SPLIT_SEGS) != 0 );
 685 }
 686
 687 template <>
 688 bool MachOLayout<arm>::isSplitSeg() const
 689 {
 690         return ( (this->getFlags() & MH_SPLIT_SEGS) != 0 );
 691 }
 692
 693 template <typename A>
 694 bool MachOLayout<A>::isSplitSeg() const
 695 {
 696         return false;
 697 }
 698
 699 template <typename A>
 700 const MachOLayoutAbstraction::Segment* MachOLayout<A>::getSegment(const char* name) const
 701 {
 702         for(std::vector<Segment>::const_iterator it = fSegments.begin(); it != fSegments.end(); ++it) {
 703                 const Segment& seg = *it;
 704                 if ( strcmp(seg.name(), name) == 0 )
 705                         return &seg;
 706         }
 707         return NULL;
 708 }
 709
 710
 711
 712 #endif // __MACHO_LAYOUT__
 713
 714
 715