ldid.cpp

   1 /* ldid - (Mach-O) Link-Loader Identity Editor
   2  * Copyright (C) 2007-2010  Jay Freeman (saurik)
   3 */
   4
   5 /*
   6  *        Redistribution and use in source and binary
   7  * forms, with or without modification, are permitted
   8  * provided that the following conditions are met:
   9  *
  10  * 1. Redistributions of source code must retain the
  11  *    above copyright notice, this list of conditions
  12  *    and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the
  14  *    above copyright notice, this list of conditions
  15  *    and the following disclaimer in the documentation
  16  *    and/or other materials provided with the
  17  *    distribution.
  18  * 3. The name of the author may not be used to endorse
  19  *    or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS''
  23  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
  24  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  25  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE
  27  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  28  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  29  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  30  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  31  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  32  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
  33  * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  34  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  35  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36 */
  37
  38 #include "minimal/stdlib.h"
  39 #include "minimal/string.h"
  40 #include "minimal/mapping.h"
  41
  42 #include "sha1.h"
  43
  44 #include <cstring>
  45 #include <string>
  46 #include <vector>
  47
  48 #include <sys/wait.h>
  49 #include <sys/types.h>
  50 #include <sys/stat.h>
  51
  52 struct fat_header {
  53     uint32_t magic;
  54     uint32_t nfat_arch;
  55 } _packed;
  56
  57 #define FAT_MAGIC 0xcafebabe
  58 #define FAT_CIGAM 0xbebafeca
  59
  60 struct fat_arch {
  61     uint32_t cputype;
  62     uint32_t cpusubtype;
  63     uint32_t offset;
  64     uint32_t size;
  65     uint32_t align;
  66 } _packed;
  67
  68 struct mach_header {
  69     uint32_t magic;
  70     uint32_t cputype;
  71     uint32_t cpusubtype;
  72     uint32_t filetype;
  73     uint32_t ncmds;
  74     uint32_t sizeofcmds;
  75     uint32_t flags;
  76 } _packed;
  77
  78 #define MH_MAGIC 0xfeedface
  79 #define MH_CIGAM 0xcefaedfe
  80
  81 #define MH_MAGIC_64 0xfeedfacf
  82 #define MH_CIGAM_64 0xcffaedfe
  83
  84 #define MH_DYLDLINK   0x4
  85
  86 #define MH_EXECUTE    0x2
  87 #define MH_DYLIB      0x6
  88 #define MH_BUNDLE     0x8
  89 #define MH_DYLIB_STUB 0x9
  90
  91 struct load_command {
  92     uint32_t cmd;
  93     uint32_t cmdsize;
  94 } _packed;
  95
  96 #define LC_REQ_DYLD           uint32_t(0x80000000)
  97
  98 #define LC_SEGMENT            uint32_t(0x01)
  99 #define LC_SYMTAB             uint32_t(0x02)
 100 #define LC_DYSYMTAB           uint32_t(0x0b)
 101 #define LC_LOAD_DYLIB         uint32_t(0x0c)
 102 #define LC_ID_DYLIB           uint32_t(0x0d)
 103 #define LC_UUID               uint32_t(0x1b)
 104 #define LC_CODE_SIGNATURE     uint32_t(0x1d)
 105 #define LC_SEGMENT_SPLIT_INFO uint32_t(0x1e)
 106 #define LC_REEXPORT_DYLIB     uint32_t(0x1f | LC_REQ_DYLD)
 107 #define LC_DYLD_INFO          uint32_t(0x22)
 108 #define LC_DYLD_INFO_ONLY     uint32_t(0x22 | LC_REQ_DYLD)
 109
 110 struct dylib {
 111     uint32_t name;
 112     uint32_t timestamp;
 113     uint32_t current_version;
 114     uint32_t compatibility_version;
 115 } _packed;
 116
 117 struct dylib_command {
 118     uint32_t cmd;
 119     uint32_t cmdsize;
 120     struct dylib dylib;
 121 } _packed;
 122
 123 struct uuid_command {
 124     uint32_t cmd;
 125     uint32_t cmdsize;
 126     uint8_t uuid[16];
 127 } _packed;
 128
 129 struct symtab_command {
 130     uint32_t cmd;
 131     uint32_t cmdsize;
 132     uint32_t symoff;
 133     uint32_t nsyms;
 134     uint32_t stroff;
 135     uint32_t strsize;
 136 } _packed;
 137
 138 struct dyld_info_command {
 139     uint32_t cmd;
 140     uint32_t cmdsize;
 141     uint32_t rebase_off;
 142     uint32_t rebase_size;
 143     uint32_t bind_off;
 144     uint32_t bind_size;
 145     uint32_t weak_bind_off;
 146     uint32_t weak_bind_size;
 147     uint32_t lazy_bind_off;
 148     uint32_t lazy_bind_size;
 149     uint32_t export_off;
 150     uint32_t export_size;
 151 } _packed;
 152
 153 struct dysymtab_command {
 154     uint32_t cmd;
 155     uint32_t cmdsize;
 156     uint32_t ilocalsym;
 157     uint32_t nlocalsym;
 158     uint32_t iextdefsym;
 159     uint32_t nextdefsym;
 160     uint32_t iundefsym;
 161     uint32_t nundefsym;
 162     uint32_t tocoff;
 163     uint32_t ntoc;
 164     uint32_t modtaboff;
 165     uint32_t nmodtab;
 166     uint32_t extrefsymoff;
 167     uint32_t nextrefsyms;
 168     uint32_t indirectsymoff;
 169     uint32_t nindirectsyms;
 170     uint32_t extreloff;
 171     uint32_t nextrel;
 172     uint32_t locreloff;
 173     uint32_t nlocrel;
 174 } _packed;
 175
 176 struct dylib_table_of_contents {
 177     uint32_t symbol_index;
 178     uint32_t module_index;
 179 } _packed;
 180
 181 struct dylib_module {
 182     uint32_t module_name;
 183     uint32_t iextdefsym;
 184     uint32_t nextdefsym;
 185     uint32_t irefsym;
 186     uint32_t nrefsym;
 187     uint32_t ilocalsym;
 188     uint32_t nlocalsym;
 189     uint32_t iextrel;
 190     uint32_t nextrel;
 191     uint32_t iinit_iterm;
 192     uint32_t ninit_nterm;
 193     uint32_t objc_module_info_addr;
 194     uint32_t objc_module_info_size;
 195 } _packed;
 196
 197 struct dylib_reference {
 198     uint32_t isym:24;
 199     uint32_t flags:8;
 200 } _packed;
 201
 202 struct relocation_info {
 203     int32_t r_address;
 204     uint32_t r_symbolnum:24;
 205     uint32_t r_pcrel:1;
 206     uint32_t r_length:2;
 207     uint32_t r_extern:1;
 208     uint32_t r_type:4;
 209 } _packed;
 210
 211 struct nlist {
 212     union {
 213         char *n_name;
 214         int32_t n_strx;
 215     } n_un;
 216
 217     uint8_t n_type;
 218     uint8_t n_sect;
 219     uint8_t n_desc;
 220     uint32_t n_value;
 221 } _packed;
 222
 223 struct segment_command {
 224     uint32_t cmd;
 225     uint32_t cmdsize;
 226     char segname[16];
 227     uint32_t vmaddr;
 228     uint32_t vmsize;
 229     uint32_t fileoff;
 230     uint32_t filesize;
 231     uint32_t maxprot;
 232     uint32_t initprot;
 233     uint32_t nsects;
 234     uint32_t flags;
 235 };
 236
 237 struct section {
 238     char sectname[16];
 239     char segname[16];
 240     uint32_t addr;
 241     uint32_t size;
 242     uint32_t offset;
 243     uint32_t align;
 244     uint32_t reloff;
 245     uint32_t nreloc;
 246     uint32_t flags;
 247     uint32_t reserved1;
 248     uint32_t reserved2;
 249 };
 250
 251 struct linkedit_data_command {
 252     uint32_t cmd;
 253     uint32_t cmdsize;
 254     uint32_t dataoff;
 255     uint32_t datasize;
 256 } _packed;
 257
 258 uint16_t Swap_(uint16_t value) {
 259     return
 260         ((value >>  8) & 0x00ff) |
 261         ((value <<  8) & 0xff00);
 262 }
 263
 264 uint32_t Swap_(uint32_t value) {
 265     value = ((value >>  8) & 0x00ff00ff) |
 266             ((value <<  8) & 0xff00ff00);
 267     value = ((value >> 16) & 0x0000ffff) |
 268             ((value << 16) & 0xffff0000);
 269     return value;
 270 }
 271
 272 int16_t Swap_(int16_t value) {
 273     return Swap_(static_cast<uint16_t>(value));
 274 }
 275
 276 int32_t Swap_(int32_t value) {
 277     return Swap_(static_cast<uint32_t>(value));
 278 }
 279
 280 bool little_(true);
 281
 282 uint16_t Swap(uint16_t value) {
 283     return little_ ? Swap_(value) : value;
 284 }
 285
 286 uint32_t Swap(uint32_t value) {
 287     return little_ ? Swap_(value) : value;
 288 }
 289
 290 int16_t Swap(int16_t value) {
 291     return Swap(static_cast<uint16_t>(value));
 292 }
 293
 294 int32_t Swap(int32_t value) {
 295     return Swap(static_cast<uint32_t>(value));
 296 }
 297
 298 template <typename Target_>
 299 class Pointer;
 300
 301 class Data {
 302   private:
 303     void *base_;
 304     size_t size_;
 305
 306   protected:
 307     bool swapped_;
 308
 309   public:
 310     Data(void *base, size_t size) :
 311         base_(base),
 312         size_(size),
 313         swapped_(false)
 314     {
 315     }
 316
 317     uint16_t Swap(uint16_t value) const {
 318         return swapped_ ? Swap_(value) : value;
 319     }
 320
 321     uint32_t Swap(uint32_t value) const {
 322         return swapped_ ? Swap_(value) : value;
 323     }
 324
 325     int16_t Swap(int16_t value) const {
 326         return Swap(static_cast<uint16_t>(value));
 327     }
 328
 329     int32_t Swap(int32_t value) const {
 330         return Swap(static_cast<uint32_t>(value));
 331     }
 332
 333     void *GetBase() const {
 334         return base_;
 335     }
 336
 337     size_t GetSize() const {
 338         return size_;
 339     }
 340 };
 341
 342 class MachHeader :
 343     public Data
 344 {
 345   private:
 346     bool bits64_;
 347
 348     struct mach_header *mach_header_;
 349     struct load_command *load_command_;
 350
 351   public:
 352     MachHeader(void *base, size_t size) :
 353         Data(base, size)
 354     {
 355         mach_header_ = (mach_header *) base;
 356
 357         switch (Swap(mach_header_->magic)) {
 358             case MH_CIGAM:
 359                 swapped_ = !swapped_;
 360             case MH_MAGIC:
 361                 bits64_ = false;
 362             break;
 363
 364             case MH_CIGAM_64:
 365                 swapped_ = !swapped_;
 366             case MH_MAGIC_64:
 367                 bits64_ = true;
 368             break;
 369
 370             default:
 371                 _assert(false);
 372         }
 373
 374         void *post = mach_header_ + 1;
 375         if (bits64_)
 376             post = (uint32_t *) post + 1;
 377         load_command_ = (struct load_command *) post;
 378
 379         _assert(
 380             Swap(mach_header_->filetype) == MH_EXECUTE ||
 381             Swap(mach_header_->filetype) == MH_DYLIB ||
 382             Swap(mach_header_->filetype) == MH_BUNDLE
 383         );
 384     }
 385
 386     struct mach_header *operator ->() const {
 387         return mach_header_;
 388     }
 389
 390     uint32_t GetCPUType() const {
 391         return Swap(mach_header_->cputype);
 392     }
 393
 394     uint16_t GetCPUSubtype() const {
 395         return Swap(mach_header_->cpusubtype) & 0xff;
 396     }
 397
 398     std::vector<struct load_command *> GetLoadCommands() const {
 399         std::vector<struct load_command *> load_commands;
 400
 401         struct load_command *load_command = load_command_;
 402         for (uint32_t cmd = 0; cmd != Swap(mach_header_->ncmds); ++cmd) {
 403             load_commands.push_back(load_command);
 404             load_command = (struct load_command *) ((uint8_t *) load_command + Swap(load_command->cmdsize));
 405         }
 406
 407         return load_commands;
 408     }
 409
 410     std::vector<segment_command *> GetSegments(const char *segment_name) {
 411         std::vector<struct segment_command *> segment_commands;
 412
 413         _foreach (load_command, GetLoadCommands())
 414             if (Swap(load_command->cmd) == LC_SEGMENT) {
 415                 segment_command *segment_command = reinterpret_cast<struct segment_command *>(load_command);
 416                 if (strncmp(segment_command->segname, segment_name, 16) == 0)
 417                     segment_commands.push_back(segment_command);
 418             }
 419
 420         return segment_commands;
 421     }
 422
 423     std::vector<section *> GetSections(const char *segment_name, const char *section_name) {
 424         std::vector<section *> sections;
 425
 426         _foreach (segment, GetSegments(segment_name)) {
 427             section *section = (struct section *) (segment + 1);
 428
 429             uint32_t sect;
 430             for (sect = 0; sect != Swap(segment->nsects); ++sect) {
 431                 if (strncmp(section->sectname, section_name, 16) == 0)
 432                     sections.push_back(section);
 433                 ++section;
 434             }
 435         }
 436
 437         return sections;
 438     }
 439
 440     template <typename Target_>
 441     Pointer<Target_> GetPointer(uint32_t address, const char *segment_name = NULL) const {
 442         load_command *load_command = (struct load_command *) (mach_header_ + 1);
 443         uint32_t cmd;
 444
 445         for (cmd = 0; cmd != Swap(mach_header_->ncmds); ++cmd) {
 446             if (Swap(load_command->cmd) == LC_SEGMENT) {
 447                 segment_command *segment_command = (struct segment_command *) load_command;
 448                 if (segment_name != NULL && strncmp(segment_command->segname, segment_name, 16) != 0)
 449                     goto next_command;
 450
 451                 section *sections = (struct section *) (segment_command + 1);
 452
 453                 uint32_t sect;
 454                 for (sect = 0; sect != Swap(segment_command->nsects); ++sect) {
 455                     section *section = &sections[sect];
 456                     //printf("%s %u %p %p %u\n", segment_command->segname, sect, address, section->addr, section->size);
 457                     if (address >= Swap(section->addr) && address < Swap(section->addr) + Swap(section->size)) {
 458                         //printf("0x%.8x %s\n", address, segment_command->segname);
 459                         return Pointer<Target_>(this, reinterpret_cast<Target_ *>(address - Swap(section->addr) + Swap(section->offset) + (char *) mach_header_));
 460                     }
 461                 }
 462             }
 463
 464           next_command:
 465             load_command = (struct load_command *) ((char *) load_command + Swap(load_command->cmdsize));
 466         }
 467
 468         return Pointer<Target_>(this);
 469     }
 470
 471     template <typename Target_>
 472     Pointer<Target_> GetOffset(uint32_t offset) {
 473         return Pointer<Target_>(this, reinterpret_cast<Target_ *>(offset + (uint8_t *) mach_header_));
 474     }
 475 };
 476
 477 class FatHeader :
 478     public Data
 479 {
 480   private:
 481     fat_header *fat_header_;
 482     std::vector<MachHeader> mach_headers_;
 483
 484   public:
 485     FatHeader(void *base, size_t size) :
 486         Data(base, size)
 487     {
 488         fat_header_ = reinterpret_cast<struct fat_header *>(base);
 489
 490         if (Swap(fat_header_->magic) == FAT_CIGAM) {
 491             swapped_ = !swapped_;
 492             goto fat;
 493         } else if (Swap(fat_header_->magic) != FAT_MAGIC) {
 494             fat_header_ = NULL;
 495             mach_headers_.push_back(MachHeader(base, size));
 496         } else fat: {
 497             size_t fat_narch = Swap(fat_header_->nfat_arch);
 498             fat_arch *fat_arch = reinterpret_cast<struct fat_arch *>(fat_header_ + 1);
 499             size_t arch;
 500             for (arch = 0; arch != fat_narch; ++arch) {
 501                 uint32_t arch_offset = Swap(fat_arch->offset);
 502                 uint32_t arch_size = Swap(fat_arch->size);
 503                 mach_headers_.push_back(MachHeader((uint8_t *) base + arch_offset, size));
 504                 ++fat_arch;
 505             }
 506         }
 507     }
 508
 509     std::vector<MachHeader> &GetMachHeaders() {
 510         return mach_headers_;
 511     }
 512
 513     bool IsFat() const {
 514         return fat_header_ != NULL;
 515     }
 516 };
 517
 518 FatHeader Map(const char *path) {
 519     size_t size;
 520     void *base(map(path, 0, _not(size_t), &size, false));
 521     return FatHeader(base, size);
 522 }
 523
 524 template <typename Target_>
 525 class Pointer {
 526   private:
 527     const MachHeader *framework_;
 528     const Target_ *pointer_;
 529
 530   public:
 531     Pointer(const MachHeader *framework = NULL, const Target_ *pointer = NULL) :
 532         framework_(framework),
 533         pointer_(pointer)
 534     {
 535     }
 536
 537     operator const Target_ *() const {
 538         return pointer_;
 539     }
 540
 541     const Target_ *operator ->() const {
 542         return pointer_;
 543     }
 544
 545     Pointer<Target_> &operator ++() {
 546         ++pointer_;
 547         return *this;
 548     }
 549
 550     template <typename Value_>
 551     Value_ Swap(Value_ value) {
 552         return framework_->Swap(value);
 553     }
 554 };
 555
 556 #define CSMAGIC_CODEDIRECTORY      uint32_t(0xfade0c02)
 557 #define CSMAGIC_EMBEDDED_SIGNATURE uint32_t(0xfade0cc0)
 558 #define CSMAGIC_ENTITLEMENTS       uint32_t(0xfade7171)
 559
 560 #define CSSLOT_CODEDIRECTORY uint32_t(0)
 561 #define CSSLOT_REQUIREMENTS  uint32_t(2)
 562 #define CSSLOT_ENTITLEMENTS  uint32_t(5)
 563
 564 struct BlobIndex {
 565     uint32_t type;
 566     uint32_t offset;
 567 } _packed;
 568
 569 struct Blob {
 570     uint32_t magic;
 571     uint32_t length;
 572 } _packed;
 573
 574 struct SuperBlob {
 575     struct Blob blob;
 576     uint32_t count;
 577     struct BlobIndex index[];
 578 } _packed;
 579
 580 struct CodeDirectory {
 581     struct Blob blob;
 582     uint32_t version;
 583     uint32_t flags;
 584     uint32_t hashOffset;
 585     uint32_t identOffset;
 586     uint32_t nSpecialSlots;
 587     uint32_t nCodeSlots;
 588     uint32_t codeLimit;
 589     uint8_t hashSize;
 590     uint8_t hashType;
 591     uint8_t spare1;
 592     uint8_t pageSize;
 593     uint32_t spare2;
 594 } _packed;
 595
 596 extern "C" uint32_t hash(uint8_t *k, uint32_t length, uint32_t initval);
 597
 598 void sha1(uint8_t *hash, uint8_t *data, size_t size) {
 599     SHA1Context context;
 600     SHA1Reset(&context);
 601     SHA1Input(&context, data, size);
 602     SHA1Result(&context, hash);
 603 }
 604
 605 struct CodesignAllocation {
 606     uint32_t type_;
 607     uint16_t subtype_;
 608     size_t size_;
 609
 610     CodesignAllocation(uint32_t type, uint16_t subtype, size_t size) :
 611         type_(type),
 612         subtype_(subtype),
 613         size_(size)
 614     {
 615     }
 616 };
 617
 618 int main(int argc, const char *argv[]) {
 619     union {
 620         uint16_t word;
 621         uint8_t byte[2];
 622     } endian = {1};
 623
 624     little_ = endian.byte[0];
 625
 626     bool flag_R(false);
 627     bool flag_r(false);
 628
 629     bool flag_t(false);
 630     bool flag_p(false);
 631     bool flag_u(false);
 632     bool flag_e(false);
 633
 634     bool flag_T(false);
 635
 636     bool flag_S(false);
 637     bool flag_s(false);
 638
 639     bool timeh(false);
 640     uint32_t timev(0);
 641
 642     const void *xmld(NULL);
 643     size_t xmls(0);
 644
 645     uintptr_t noffset(_not(uintptr_t));
 646     uintptr_t woffset(_not(uintptr_t));
 647
 648     std::vector<std::string> files;
 649
 650     if (argc == 1) {
 651         fprintf(stderr, "usage: %s -S[entitlements.xml] <binary>\n", argv[0]);
 652         fprintf(stderr, "   %s -e MobileSafari\n", argv[0]);
 653         fprintf(stderr, "   %s -S cat\n", argv[0]);
 654         fprintf(stderr, "   %s -Stfp.xml gdb\n", argv[0]);
 655         exit(0);
 656     }
 657
 658     for (int argi(1); argi != argc; ++argi)
 659         if (argv[argi][0] != '-')
 660             files.push_back(argv[argi]);
 661         else switch (argv[argi][1]) {
 662             case 'R': flag_R = true; break;
 663             case 'r': flag_r = true; break;
 664
 665             case 't': flag_t = true; break;
 666             case 'u': flag_u = true; break;
 667             case 'p': flag_p = true; break;
 668             case 'e': flag_e = true; break;
 669
 670             case 's':
 671                 _assert(!flag_S);
 672                 flag_s = true;
 673             break;
 674
 675             case 'S':
 676                 _assert(!flag_s);
 677                 flag_S = true;
 678                 if (argv[argi][2] != '\0') {
 679                     const char *xml = argv[argi] + 2;
 680                     xmld = map(xml, 0, _not(size_t), &xmls, true);
 681                 }
 682             break;
 683
 684             case 'T': {
 685                 flag_T = true;
 686                 if (argv[argi][2] == '-')
 687                     timeh = true;
 688                 else {
 689                     char *arge;
 690                     timev = strtoul(argv[argi] + 2, &arge, 0);
 691                     _assert(arge == argv[argi] + strlen(argv[argi]));
 692                 }
 693             } break;
 694
 695             case 'n': {
 696                 char *arge;
 697                 noffset = strtoul(argv[argi] + 2, &arge, 0);
 698                 _assert(arge == argv[argi] + strlen(argv[argi]));
 699             } break;
 700
 701             case 'w': {
 702                 char *arge;
 703                 woffset = strtoul(argv[argi] + 2, &arge, 0);
 704                 _assert(arge == argv[argi] + strlen(argv[argi]));
 705             } break;
 706
 707             default:
 708                 goto usage;
 709             break;
 710         }
 711
 712     if (files.empty()) usage: {
 713         exit(0);
 714     }
 715
 716     size_t filei(0), filee(0);
 717     _foreach (file, files) try {
 718         const char *path(file.c_str());
 719         const char *base = strrchr(path, '/');
 720         char *temp(NULL), *dir;
 721
 722         if (base != NULL)
 723             dir = strndup_(path, base++ - path + 1);
 724         else {
 725             dir = strdup("");
 726             base = path;
 727         }
 728
 729         if (flag_r) {
 730             size_t clip(_not(size_t)); {
 731                 FatHeader fat_header(Map(path));
 732                 _foreach (mach_header, fat_header.GetMachHeaders()) {
 733                     mach_header->flags = mach_header.Swap(mach_header.Swap(mach_header->flags) | MH_DYLDLINK);
 734
 735                     size_t size(_not(size_t)); {
 736                         _foreach (load_command, mach_header.GetLoadCommands()) {
 737                             switch (mach_header.Swap(load_command->cmd)) {
 738                                 case LC_CODE_SIGNATURE: {
 739                                     struct linkedit_data_command *signature = reinterpret_cast<struct linkedit_data_command *>(load_command);
 740                                     memset(signature, 0, sizeof(struct linkedit_data_command));
 741
 742                                     mach_header->ncmds -= 1;
 743                                     mach_header->sizeofcmds -= sizeof(struct linkedit_data_command);
 744                                 } break;
 745
 746                                 case LC_SYMTAB: {
 747                                     struct symtab_command *symtab = reinterpret_cast<struct symtab_command *>(load_command);
 748                                     size = symtab->stroff + symtab->strsize;
 749                                 } break;
 750                             }
 751                         }
 752
 753                         _foreach (segment, const_cast<MachHeader &>(mach_header).GetSegments("__LINKEDIT")) {
 754                             segment->filesize -= mach_header.GetSize() - size;
 755
 756                             if (!fat_header.IsFat())
 757                                 clip = size;
 758                             else
 759                                 _assert(false);
 760                         }
 761                     }
 762                 }
 763             }
 764
 765             if (clip != _not(size_t))
 766                 _syscall(truncate(path, clip));
 767         }
 768
 769         if (flag_S) {
 770             asprintf(&temp, "%s.%s.cs", dir, base);
 771             const char *allocate = getenv("CODESIGN_ALLOCATE");
 772             if (allocate == NULL)
 773                 allocate = "codesign_allocate";
 774
 775             std::vector<CodesignAllocation> allocations; {
 776                 FatHeader fat_header(Map(path));
 777                 _foreach (mach_header, fat_header.GetMachHeaders()) {
 778                     mach_header->flags = mach_header.Swap(mach_header.Swap(mach_header->flags) | MH_DYLDLINK);
 779
 780                     size_t size(_not(size_t)); {
 781                         _foreach (load_command, mach_header.GetLoadCommands()) {
 782                             uint32_t cmd(mach_header.Swap(load_command->cmd));
 783                             if (cmd == LC_CODE_SIGNATURE) {
 784                                 struct linkedit_data_command *signature = reinterpret_cast<struct linkedit_data_command *>(load_command);
 785                                 size = mach_header.Swap(signature->dataoff);
 786                                 _assert(size < mach_header.GetSize());
 787                                 break;
 788                             }
 789                         }
 790
 791                         if (size == _not(size_t))
 792                             size = mach_header.GetSize();
 793                     }
 794
 795                     allocations.push_back(CodesignAllocation(mach_header.GetCPUType(), mach_header.GetCPUSubtype(), size));
 796                 }
 797             }
 798
 799             pid_t pid = fork();
 800             _syscall(pid);
 801             if (pid == 0) {
 802                 // XXX: this leaks memory, but it doesn't really matter
 803                 std::vector<const char *> args;
 804                 char *arg;
 805
 806                 args.push_back(allocate);
 807
 808                 args.push_back("-i");
 809                 args.push_back(path);
 810
 811                 _foreach (allocation, allocations) {
 812                     args.push_back("-A");
 813
 814                     asprintf(&arg, "%u", allocation.type_);
 815                     args.push_back(arg);
 816
 817                     asprintf(&arg, "%u", allocation.subtype_);
 818                     args.push_back(arg);
 819
 820                     size_t alloc(0);
 821                     alloc += sizeof(struct SuperBlob);
 822                     uint32_t special(0);
 823
 824                     special = std::max(special, CSSLOT_CODEDIRECTORY);
 825                     alloc += sizeof(struct BlobIndex);
 826                     alloc += sizeof(struct CodeDirectory);
 827                     alloc += strlen(base) + 1;
 828
 829                     special = std::max(special, CSSLOT_REQUIREMENTS);
 830                     alloc += sizeof(struct BlobIndex);
 831                     alloc += 0xc;
 832
 833                     if (xmld != NULL) {
 834                         special = std::max(special, CSSLOT_ENTITLEMENTS);
 835                         alloc += sizeof(struct BlobIndex);
 836                         alloc += sizeof(struct Blob);
 837                         alloc += xmls;
 838                     }
 839
 840                     size_t normal((allocation.size_ + 0x1000 - 1) / 0x1000);
 841                     alloc += (special + normal) * 0x14;
 842
 843                     alloc += 15;
 844                     alloc /= 16;
 845                     alloc *= 16;
 846
 847                     asprintf(&arg, "%u", alloc);
 848                     args.push_back(arg);
 849                 }
 850
 851                 args.push_back("-o");
 852                 args.push_back(temp);
 853
 854                 args.push_back(NULL);
 855
 856                 if (false) {
 857                     printf("run:");
 858                     _foreach (arg, args)
 859                         printf(" %s", arg);
 860                     printf("\n");
 861                 }
 862
 863                 execvp(allocate, (char **) &args[0]);
 864                 _assert(false);
 865             }
 866
 867             int status;
 868             _syscall(waitpid(pid, &status, 0));
 869             _assert(WIFEXITED(status));
 870             _assert(WEXITSTATUS(status) == 0);
 871         }
 872
 873         if (flag_p)
 874             printf("path%zu='%s'\n", filei, file.c_str());
 875
 876         FatHeader fat_header(Map(temp == NULL ? path : temp));
 877         struct linkedit_data_command *signature(NULL);
 878
 879         _foreach (mach_header, fat_header.GetMachHeaders()) {
 880             if (woffset != _not(uintptr_t)) {
 881                 Pointer<uint32_t> wvalue(mach_header.GetPointer<uint32_t>(woffset));
 882                 if (wvalue == NULL)
 883                     printf("(null) %p\n", reinterpret_cast<void *>(woffset));
 884                 else
 885                     printf("0x%.08x\n", *wvalue);
 886             }
 887
 888             if (noffset != _not(uintptr_t))
 889                 printf("%s\n", &*mach_header.GetPointer<char>(noffset));
 890
 891             _foreach (load_command, mach_header.GetLoadCommands()) {
 892                 uint32_t cmd(mach_header.Swap(load_command->cmd));
 893
 894                 if (flag_R && cmd == LC_REEXPORT_DYLIB)
 895                     load_command->cmd = mach_header.Swap(LC_LOAD_DYLIB);
 896                 else if (cmd == LC_CODE_SIGNATURE)
 897                     signature = reinterpret_cast<struct linkedit_data_command *>(load_command);
 898                 else if (cmd == LC_UUID) {
 899                     volatile struct uuid_command *uuid_command(reinterpret_cast<struct uuid_command *>(load_command));
 900
 901                     if (flag_u) {
 902                         printf("uuid%zu=%.2x%.2x%.2x%.2x-%.2x%.2x-%.2x%.2x-%.2x%.2x-%.2x%.2x%.2x%.2x%.2x%.2x\n", filei,
 903                             uuid_command->uuid[ 0], uuid_command->uuid[ 1], uuid_command->uuid[ 2], uuid_command->uuid[ 3],
 904                             uuid_command->uuid[ 4], uuid_command->uuid[ 5], uuid_command->uuid[ 6], uuid_command->uuid[ 7],
 905                             uuid_command->uuid[ 8], uuid_command->uuid[ 9], uuid_command->uuid[10], uuid_command->uuid[11],
 906                             uuid_command->uuid[12], uuid_command->uuid[13], uuid_command->uuid[14], uuid_command->uuid[15]
 907                         );
 908                     }
 909                 } else if (cmd == LC_ID_DYLIB) {
 910                     volatile struct dylib_command *dylib_command(reinterpret_cast<struct dylib_command *>(load_command));
 911
 912                     if (flag_t)
 913                         printf("time%zu=0x%.8x\n", filei, mach_header.Swap(dylib_command->dylib.timestamp));
 914
 915                     if (flag_T) {
 916                         uint32_t timed;
 917
 918                         if (!timeh)
 919                             timed = timev;
 920                         else {
 921                             dylib_command->dylib.timestamp = 0;
 922                             timed = hash(reinterpret_cast<uint8_t *>(mach_header.GetBase()), mach_header.GetSize(), timev);
 923                         }
 924
 925                         dylib_command->dylib.timestamp = mach_header.Swap(timed);
 926                     }
 927                 }
 928             }
 929
 930             if (flag_e) {
 931                 _assert(signature != NULL);
 932
 933                 uint32_t data = mach_header.Swap(signature->dataoff);
 934                 uint32_t size = mach_header.Swap(signature->datasize);
 935
 936                 uint8_t *top = reinterpret_cast<uint8_t *>(mach_header.GetBase());
 937                 uint8_t *blob = top + data;
 938                 struct SuperBlob *super = reinterpret_cast<struct SuperBlob *>(blob);
 939
 940                 for (size_t index(0); index != Swap(super->count); ++index)
 941                     if (Swap(super->index[index].type) == CSSLOT_ENTITLEMENTS) {
 942                         uint32_t begin = Swap(super->index[index].offset);
 943                         struct Blob *entitlements = reinterpret_cast<struct Blob *>(blob + begin);
 944                         fwrite(entitlements + 1, 1, Swap(entitlements->length) - sizeof(struct Blob), stdout);
 945                     }
 946             }
 947
 948             if (flag_s) {
 949                 _assert(signature != NULL);
 950
 951                 uint32_t data = mach_header.Swap(signature->dataoff);
 952                 uint32_t size = mach_header.Swap(signature->datasize);
 953
 954                 uint8_t *top = reinterpret_cast<uint8_t *>(mach_header.GetBase());
 955                 uint8_t *blob = top + data;
 956                 struct SuperBlob *super = reinterpret_cast<struct SuperBlob *>(blob);
 957
 958                 for (size_t index(0); index != Swap(super->count); ++index)
 959                     if (Swap(super->index[index].type) == CSSLOT_CODEDIRECTORY) {
 960                         uint32_t begin = Swap(super->index[index].offset);
 961                         struct CodeDirectory *directory = reinterpret_cast<struct CodeDirectory *>(blob + begin);
 962
 963                         uint8_t (*hashes)[20] = reinterpret_cast<uint8_t (*)[20]>(blob + begin + Swap(directory->hashOffset));
 964                         uint32_t pages = Swap(directory->nCodeSlots);
 965
 966                         if (pages != 1)
 967                             for (size_t i = 0; i != pages - 1; ++i)
 968                                 sha1(hashes[i], top + 0x1000 * i, 0x1000);
 969                         if (pages != 0)
 970                             sha1(hashes[pages - 1], top + 0x1000 * (pages - 1), ((data - 1) % 0x1000) + 1);
 971                     }
 972             }
 973
 974             if (flag_S) {
 975                 _assert(signature != NULL);
 976
 977                 uint32_t data = mach_header.Swap(signature->dataoff);
 978                 uint32_t size = mach_header.Swap(signature->datasize);
 979
 980                 uint8_t *top = reinterpret_cast<uint8_t *>(mach_header.GetBase());
 981                 uint8_t *blob = top + data;
 982                 struct SuperBlob *super = reinterpret_cast<struct SuperBlob *>(blob);
 983                 super->blob.magic = Swap(CSMAGIC_EMBEDDED_SIGNATURE);
 984
 985                 uint32_t count = xmld == NULL ? 2 : 3;
 986                 uint32_t offset = sizeof(struct SuperBlob) + count * sizeof(struct BlobIndex);
 987
 988                 super->index[0].type = Swap(CSSLOT_CODEDIRECTORY);
 989                 super->index[0].offset = Swap(offset);
 990
 991                 uint32_t begin = offset;
 992                 struct CodeDirectory *directory = reinterpret_cast<struct CodeDirectory *>(blob + begin);
 993                 offset += sizeof(struct CodeDirectory);
 994
 995                 directory->blob.magic = Swap(CSMAGIC_CODEDIRECTORY);
 996                 directory->version = Swap(uint32_t(0x00020001));
 997                 directory->flags = Swap(uint32_t(0));
 998                 directory->codeLimit = Swap(data);
 999                 directory->hashSize = 0x14;
1000                 directory->hashType = 0x01;
1001                 directory->spare1 = 0x00;
1002                 directory->pageSize = 0x0c;
1003                 directory->spare2 = Swap(uint32_t(0));
1004
1005                 directory->identOffset = Swap(offset - begin);
1006                 strcpy(reinterpret_cast<char *>(blob + offset), base);
1007                 offset += strlen(base) + 1;
1008
1009                 uint32_t special = xmld == NULL ? CSSLOT_REQUIREMENTS : CSSLOT_ENTITLEMENTS;
1010                 directory->nSpecialSlots = Swap(special);
1011
1012                 uint8_t (*hashes)[20] = reinterpret_cast<uint8_t (*)[20]>(blob + offset);
1013                 memset(hashes, 0, sizeof(*hashes) * special);
1014
1015                 offset += sizeof(*hashes) * special;
1016                 hashes += special;
1017
1018                 uint32_t pages = (data + 0x1000 - 1) / 0x1000;
1019                 directory->nCodeSlots = Swap(pages);
1020
1021                 if (pages != 1)
1022                     for (size_t i = 0; i != pages - 1; ++i)
1023                         sha1(hashes[i], top + 0x1000 * i, 0x1000);
1024                 if (pages != 0)
1025                     sha1(hashes[pages - 1], top + 0x1000 * (pages - 1), ((data - 1) % 0x1000) + 1);
1026
1027                 directory->hashOffset = Swap(offset - begin);
1028                 offset += sizeof(*hashes) * pages;
1029                 directory->blob.length = Swap(offset - begin);
1030
1031                 super->index[1].type = Swap(CSSLOT_REQUIREMENTS);
1032                 super->index[1].offset = Swap(offset);
1033
1034                 memcpy(blob + offset, "\xfa\xde\x0c\x01\x00\x00\x00\x0c\x00\x00\x00\x00", 0xc);
1035                 offset += 0xc;
1036
1037                 if (xmld != NULL) {
1038                     super->index[2].type = Swap(CSSLOT_ENTITLEMENTS);
1039                     super->index[2].offset = Swap(offset);
1040
1041                     uint32_t begin = offset;
1042                     struct Blob *entitlements = reinterpret_cast<struct Blob *>(blob + begin);
1043                     offset += sizeof(struct Blob);
1044
1045                     memcpy(blob + offset, xmld, xmls);
1046                     offset += xmls;
1047
1048                     entitlements->magic = Swap(CSMAGIC_ENTITLEMENTS);
1049                     entitlements->length = Swap(offset - begin);
1050                 }
1051
1052                 for (size_t index(0); index != count; ++index) {
1053                     uint32_t type = Swap(super->index[index].type);
1054                     if (type != 0 && type <= special) {
1055                         uint32_t offset = Swap(super->index[index].offset);
1056                         struct Blob *local = (struct Blob *) (blob + offset);
1057                         sha1((uint8_t *) (hashes - type), (uint8_t *) local, Swap(local->length));
1058                     }
1059                 }
1060
1061                 super->count = Swap(count);
1062                 super->blob.length = Swap(offset);
1063
1064                 if (offset > size) {
1065                     fprintf(stderr, "offset (%u) > size (%u)\n", offset, size);
1066                     _assert(false);
1067                 } //else fprintf(stderr, "offset (%zu) <= size (%zu)\n", offset, size);
1068
1069                 memset(blob + offset, 0, size - offset);
1070             }
1071         }
1072
1073         if (flag_S) {
1074             uint8_t *top = reinterpret_cast<uint8_t *>(fat_header.GetBase());
1075             size_t size = fat_header.GetSize();
1076
1077             char *copy;
1078             asprintf(&copy, "%s.%s.cp", dir, base);
1079             FILE *file = fopen(copy, "w+");
1080             size_t writ = fwrite(top, 1, size, file);
1081             _assert(writ == size);
1082             fclose(file);
1083
1084             _syscall(unlink(temp));
1085             free(temp);
1086             temp = copy;
1087         }
1088
1089         if (temp != NULL) {
1090             struct stat info;
1091             _syscall(stat(path, &info));
1092             _syscall(chown(temp, info.st_uid, info.st_gid));
1093             _syscall(chmod(temp, info.st_mode));
1094             _syscall(unlink(path));
1095             _syscall(rename(temp, path));
1096             free(temp);
1097         }
1098
1099         free(dir);
1100         ++filei;
1101     } catch (const char *) {
1102         ++filee;
1103         ++filei;
1104     }
1105
1106     return filee;
1107 }