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_LOAD_DYLIB      uint32_t(0x0c)
 100 #define LC_ID_DYLIB        uint32_t(0x0d)
 101 #define LC_UUID            uint32_t(0x1b)
 102 #define LC_CODE_SIGNATURE  uint32_t(0x1d)
 103 #define LC_REEXPORT_DYLIB  uint32_t(0x1f | LC_REQ_DYLD)
 104
 105 struct dylib {
 106     uint32_t name;
 107     uint32_t timestamp;
 108     uint32_t current_version;
 109     uint32_t compatibility_version;
 110 } _packed;
 111
 112 struct dylib_command {
 113     uint32_t cmd;
 114     uint32_t cmdsize;
 115     struct dylib dylib;
 116 } _packed;
 117
 118 struct uuid_command {
 119     uint32_t cmd;
 120     uint32_t cmdsize;
 121     uint8_t uuid[16];
 122 } _packed;
 123
 124 struct segment_command {
 125     uint32_t cmd;
 126     uint32_t cmdsize;
 127     char segname[16];
 128     uint32_t vmaddr;
 129     uint32_t vmsize;
 130     uint32_t fileoff;
 131     uint32_t filesize;
 132     uint32_t maxprot;
 133     uint32_t initprot;
 134     uint32_t nsects;
 135     uint32_t flags;
 136 };
 137
 138 struct section {
 139     char sectname[16];
 140     char segname[16];
 141     uint32_t addr;
 142     uint32_t size;
 143     uint32_t offset;
 144     uint32_t align;
 145     uint32_t reloff;
 146     uint32_t nreloc;
 147     uint32_t flags;
 148     uint32_t reserved1;
 149     uint32_t reserved2;
 150 };
 151
 152 struct linkedit_data_command {
 153     uint32_t cmd;
 154     uint32_t cmdsize;
 155     uint32_t dataoff;
 156     uint32_t datasize;
 157 } _packed;
 158
 159 uint16_t Swap_(uint16_t value) {
 160     return
 161         ((value >>  8) & 0x00ff) |
 162         ((value <<  8) & 0xff00);
 163 }
 164
 165 uint32_t Swap_(uint32_t value) {
 166     value = ((value >>  8) & 0x00ff00ff) |
 167             ((value <<  8) & 0xff00ff00);
 168     value = ((value >> 16) & 0x0000ffff) |
 169             ((value << 16) & 0xffff0000);
 170     return value;
 171 }
 172
 173 int16_t Swap_(int16_t value) {
 174     return Swap_(static_cast<uint16_t>(value));
 175 }
 176
 177 int32_t Swap_(int32_t value) {
 178     return Swap_(static_cast<uint32_t>(value));
 179 }
 180
 181 bool little_(true);
 182
 183 uint16_t Swap(uint16_t value) {
 184     return little_ ? Swap_(value) : value;
 185 }
 186
 187 uint32_t Swap(uint32_t value) {
 188     return little_ ? Swap_(value) : value;
 189 }
 190
 191 int16_t Swap(int16_t value) {
 192     return Swap(static_cast<uint16_t>(value));
 193 }
 194
 195 int32_t Swap(int32_t value) {
 196     return Swap(static_cast<uint32_t>(value));
 197 }
 198
 199 template <typename Target_>
 200 class Pointer;
 201
 202 class Data {
 203   private:
 204     void *base_;
 205     size_t size_;
 206
 207   protected:
 208     bool swapped_;
 209
 210   public:
 211     Data(void *base, size_t size) :
 212         base_(base),
 213         size_(size),
 214         swapped_(false)
 215     {
 216     }
 217
 218     uint16_t Swap(uint16_t value) const {
 219         return swapped_ ? Swap_(value) : value;
 220     }
 221
 222     uint32_t Swap(uint32_t value) const {
 223         return swapped_ ? Swap_(value) : value;
 224     }
 225
 226     int16_t Swap(int16_t value) const {
 227         return Swap(static_cast<uint16_t>(value));
 228     }
 229
 230     int32_t Swap(int32_t value) const {
 231         return Swap(static_cast<uint32_t>(value));
 232     }
 233
 234     void *GetBase() const {
 235         return base_;
 236     }
 237
 238     size_t GetSize() const {
 239         return size_;
 240     }
 241 };
 242
 243 class MachHeader :
 244     public Data
 245 {
 246   private:
 247     bool bits64_;
 248
 249     struct mach_header *mach_header_;
 250     struct load_command *load_command_;
 251
 252   public:
 253     MachHeader(void *base, size_t size) :
 254         Data(base, size)
 255     {
 256         mach_header_ = (mach_header *) base;
 257
 258         switch (Swap(mach_header_->magic)) {
 259             case MH_CIGAM:
 260                 swapped_ = !swapped_;
 261             case MH_MAGIC:
 262                 bits64_ = false;
 263             break;
 264
 265             case MH_CIGAM_64:
 266                 swapped_ = !swapped_;
 267             case MH_MAGIC_64:
 268                 bits64_ = true;
 269             break;
 270
 271             default:
 272                 _assert(false);
 273         }
 274
 275         void *post = mach_header_ + 1;
 276         if (bits64_)
 277             post = (uint32_t *) post + 1;
 278         load_command_ = (struct load_command *) post;
 279
 280         _assert(
 281             Swap(mach_header_->filetype) == MH_EXECUTE ||
 282             Swap(mach_header_->filetype) == MH_DYLIB ||
 283             Swap(mach_header_->filetype) == MH_BUNDLE
 284         );
 285     }
 286
 287     struct mach_header *operator ->() const {
 288         return mach_header_;
 289     }
 290
 291     uint32_t GetCPUType() const {
 292         return Swap(mach_header_->cputype);
 293     }
 294
 295     uint16_t GetCPUSubtype() const {
 296         return Swap(mach_header_->cpusubtype) & 0xff;
 297     }
 298
 299     std::vector<struct load_command *> GetLoadCommands() const {
 300         std::vector<struct load_command *> load_commands;
 301
 302         struct load_command *load_command = load_command_;
 303         for (uint32_t cmd = 0; cmd != Swap(mach_header_->ncmds); ++cmd) {
 304             load_commands.push_back(load_command);
 305             load_command = (struct load_command *) ((uint8_t *) load_command + Swap(load_command->cmdsize));
 306         }
 307
 308         return load_commands;
 309     }
 310
 311     std::vector<segment_command *> GetSegments(const char *segment_name) {
 312         std::vector<struct segment_command *> segment_commands;
 313
 314         _foreach (load_command, GetLoadCommands())
 315             if (Swap(load_command->cmd) == LC_SEGMENT) {
 316                 segment_command *segment_command = reinterpret_cast<struct segment_command *>(load_command);
 317                 if (strncmp(segment_command->segname, segment_name, 16) == 0)
 318                     segment_commands.push_back(segment_command);
 319             }
 320
 321         return segment_commands;
 322     }
 323
 324     std::vector<section *> GetSections(const char *segment_name, const char *section_name) {
 325         std::vector<section *> sections;
 326
 327         _foreach (segment, GetSegments(segment_name)) {
 328             section *section = (struct section *) (segment + 1);
 329
 330             uint32_t sect;
 331             for (sect = 0; sect != Swap(segment->nsects); ++sect) {
 332                 if (strncmp(section->sectname, section_name, 16) == 0)
 333                     sections.push_back(section);
 334                 ++section;
 335             }
 336         }
 337
 338         return sections;
 339     }
 340
 341     template <typename Target_>
 342     Pointer<Target_> GetPointer(uint32_t address, const char *segment_name = NULL) const {
 343         load_command *load_command = (struct load_command *) (mach_header_ + 1);
 344         uint32_t cmd;
 345
 346         for (cmd = 0; cmd != Swap(mach_header_->ncmds); ++cmd) {
 347             if (Swap(load_command->cmd) == LC_SEGMENT) {
 348                 segment_command *segment_command = (struct segment_command *) load_command;
 349                 if (segment_name != NULL && strncmp(segment_command->segname, segment_name, 16) != 0)
 350                     goto next_command;
 351
 352                 section *sections = (struct section *) (segment_command + 1);
 353
 354                 uint32_t sect;
 355                 for (sect = 0; sect != Swap(segment_command->nsects); ++sect) {
 356                     section *section = &sections[sect];
 357                     //printf("%s %u %p %p %u\n", segment_command->segname, sect, address, section->addr, section->size);
 358                     if (address >= Swap(section->addr) && address < Swap(section->addr) + Swap(section->size)) {
 359                         //printf("0x%.8x %s\n", address, segment_command->segname);
 360                         return Pointer<Target_>(this, reinterpret_cast<Target_ *>(address - Swap(section->addr) + Swap(section->offset) + (char *) mach_header_));
 361                     }
 362                 }
 363             }
 364
 365           next_command:
 366             load_command = (struct load_command *) ((char *) load_command + Swap(load_command->cmdsize));
 367         }
 368
 369         return Pointer<Target_>(this);
 370     }
 371
 372     template <typename Target_>
 373     Pointer<Target_> GetOffset(uint32_t offset) {
 374         return Pointer<Target_>(this, reinterpret_cast<Target_ *>(offset + (uint8_t *) mach_header_));
 375     }
 376 };
 377
 378 class FatHeader :
 379     public Data
 380 {
 381   private:
 382     fat_header *fat_header_;
 383     std::vector<MachHeader> mach_headers_;
 384
 385   public:
 386     FatHeader(void *base, size_t size) :
 387         Data(base, size)
 388     {
 389         fat_header_ = reinterpret_cast<struct fat_header *>(base);
 390
 391         if (Swap(fat_header_->magic) == FAT_CIGAM) {
 392             swapped_ = !swapped_;
 393             goto fat;
 394         } else if (Swap(fat_header_->magic) != FAT_MAGIC) {
 395             fat_header_ = NULL;
 396             mach_headers_.push_back(MachHeader(base, size));
 397         } else fat: {
 398             size_t fat_narch = Swap(fat_header_->nfat_arch);
 399             fat_arch *fat_arch = reinterpret_cast<struct fat_arch *>(fat_header_ + 1);
 400             size_t arch;
 401             for (arch = 0; arch != fat_narch; ++arch) {
 402                 uint32_t arch_offset = Swap(fat_arch->offset);
 403                 uint32_t arch_size = Swap(fat_arch->size);
 404                 mach_headers_.push_back(MachHeader((uint8_t *) base + arch_offset, size));
 405                 ++fat_arch;
 406             }
 407         }
 408     }
 409
 410     std::vector<MachHeader> &GetMachHeaders() {
 411         return mach_headers_;
 412     }
 413 };
 414
 415 FatHeader Map(const char *path) {
 416     size_t size;
 417     void *base(map(path, 0, _not(size_t), &size, false));
 418     return FatHeader(base, size);
 419 }
 420
 421 template <typename Target_>
 422 class Pointer {
 423   private:
 424     const MachHeader *framework_;
 425     const Target_ *pointer_;
 426
 427   public:
 428     Pointer(const MachHeader *framework = NULL, const Target_ *pointer = NULL) :
 429         framework_(framework),
 430         pointer_(pointer)
 431     {
 432     }
 433
 434     operator const Target_ *() const {
 435         return pointer_;
 436     }
 437
 438     const Target_ *operator ->() const {
 439         return pointer_;
 440     }
 441
 442     Pointer<Target_> &operator ++() {
 443         ++pointer_;
 444         return *this;
 445     }
 446
 447     template <typename Value_>
 448     Value_ Swap(Value_ value) {
 449         return framework_->Swap(value);
 450     }
 451 };
 452
 453 #define CSMAGIC_CODEDIRECTORY      uint32_t(0xfade0c02)
 454 #define CSMAGIC_EMBEDDED_SIGNATURE uint32_t(0xfade0cc0)
 455 #define CSMAGIC_ENTITLEMENTS       uint32_t(0xfade7171)
 456
 457 #define CSSLOT_CODEDIRECTORY uint32_t(0)
 458 #define CSSLOT_REQUIREMENTS  uint32_t(2)
 459 #define CSSLOT_ENTITLEMENTS  uint32_t(5)
 460
 461 struct BlobIndex {
 462     uint32_t type;
 463     uint32_t offset;
 464 } _packed;
 465
 466 struct Blob {
 467     uint32_t magic;
 468     uint32_t length;
 469 } _packed;
 470
 471 struct SuperBlob {
 472     struct Blob blob;
 473     uint32_t count;
 474     struct BlobIndex index[];
 475 } _packed;
 476
 477 struct CodeDirectory {
 478     struct Blob blob;
 479     uint32_t version;
 480     uint32_t flags;
 481     uint32_t hashOffset;
 482     uint32_t identOffset;
 483     uint32_t nSpecialSlots;
 484     uint32_t nCodeSlots;
 485     uint32_t codeLimit;
 486     uint8_t hashSize;
 487     uint8_t hashType;
 488     uint8_t spare1;
 489     uint8_t pageSize;
 490     uint32_t spare2;
 491 } _packed;
 492
 493 extern "C" uint32_t hash(uint8_t *k, uint32_t length, uint32_t initval);
 494
 495 void sha1(uint8_t *hash, uint8_t *data, size_t size) {
 496     SHA1Context context;
 497     SHA1Reset(&context);
 498     SHA1Input(&context, data, size);
 499     SHA1Result(&context, hash);
 500 }
 501
 502 struct CodesignAllocation {
 503     uint32_t type_;
 504     uint16_t subtype_;
 505     size_t size_;
 506
 507     CodesignAllocation(uint32_t type, uint16_t subtype, size_t size) :
 508         type_(type),
 509         subtype_(subtype),
 510         size_(size)
 511     {
 512     }
 513 };
 514
 515 int main(int argc, const char *argv[]) {
 516     union {
 517         uint16_t word;
 518         uint8_t byte[2];
 519     } endian = {1};
 520
 521     little_ = endian.byte[0];
 522
 523     bool flag_R(false);
 524     bool flag_t(false);
 525     bool flag_p(false);
 526     bool flag_u(false);
 527     bool flag_e(false);
 528
 529     bool flag_T(false);
 530
 531     bool flag_S(false);
 532     bool flag_s(false);
 533
 534     bool timeh(false);
 535     uint32_t timev(0);
 536
 537     const void *xmld(NULL);
 538     size_t xmls(0);
 539
 540     uintptr_t noffset(_not(uintptr_t));
 541     uintptr_t woffset(_not(uintptr_t));
 542
 543     std::vector<std::string> files;
 544
 545     if (argc == 1) {
 546         fprintf(stderr, "usage: %s -S[entitlements.xml] <binary>\n", argv[0]);
 547         fprintf(stderr, "   %s -e MobileSafari\n", argv[0]);
 548         fprintf(stderr, "   %s -S cat\n", argv[0]);
 549         fprintf(stderr, "   %s -Stfp.xml gdb\n", argv[0]);
 550         exit(0);
 551     }
 552
 553     for (int argi(1); argi != argc; ++argi)
 554         if (argv[argi][0] != '-')
 555             files.push_back(argv[argi]);
 556         else switch (argv[argi][1]) {
 557             case 'R': flag_R = true; break;
 558             case 't': flag_t = true; break;
 559             case 'u': flag_u = true; break;
 560             case 'p': flag_p = true; break;
 561             case 'e': flag_e = true; break;
 562
 563             case 's':
 564                 _assert(!flag_S);
 565                 flag_s = true;
 566             break;
 567
 568             case 'S':
 569                 _assert(!flag_s);
 570                 flag_S = true;
 571                 if (argv[argi][2] != '\0') {
 572                     const char *xml = argv[argi] + 2;
 573                     xmld = map(xml, 0, _not(size_t), &xmls, true);
 574                 }
 575             break;
 576
 577             case 'T': {
 578                 flag_T = true;
 579                 if (argv[argi][2] == '-')
 580                     timeh = true;
 581                 else {
 582                     char *arge;
 583                     timev = strtoul(argv[argi] + 2, &arge, 0);
 584                     _assert(arge == argv[argi] + strlen(argv[argi]));
 585                 }
 586             } break;
 587
 588             case 'n': {
 589                 char *arge;
 590                 noffset = strtoul(argv[argi] + 2, &arge, 0);
 591                 _assert(arge == argv[argi] + strlen(argv[argi]));
 592             } break;
 593
 594             case 'w': {
 595                 char *arge;
 596                 woffset = strtoul(argv[argi] + 2, &arge, 0);
 597                 _assert(arge == argv[argi] + strlen(argv[argi]));
 598             } break;
 599
 600             default:
 601                 goto usage;
 602             break;
 603         }
 604
 605     if (files.empty()) usage: {
 606         exit(0);
 607     }
 608
 609     size_t filei(0), filee(0);
 610     _foreach (file, files) try {
 611         const char *path(file.c_str());
 612         const char *base = strrchr(path, '/');
 613         char *temp(NULL), *dir;
 614
 615         if (base != NULL)
 616             dir = strndup_(path, base++ - path + 1);
 617         else {
 618             dir = strdup("");
 619             base = path;
 620         }
 621
 622         if (flag_S) {
 623             asprintf(&temp, "%s.%s.cs", dir, base);
 624             const char *allocate = getenv("CODESIGN_ALLOCATE");
 625             if (allocate == NULL)
 626                 allocate = "codesign_allocate";
 627
 628             std::vector<CodesignAllocation> allocations; {
 629                 FatHeader fat_header(Map(path));
 630                 _foreach (mach_header, fat_header.GetMachHeaders()) {
 631                     mach_header->flags = mach_header.Swap(mach_header.Swap(mach_header->flags) | MH_DYLDLINK);
 632
 633                     size_t size(_not(size_t)); {
 634                         _foreach (load_command, mach_header.GetLoadCommands()) {
 635                             uint32_t cmd(mach_header.Swap(load_command->cmd));
 636                             if (cmd == LC_CODE_SIGNATURE) {
 637                                 struct linkedit_data_command *signature = reinterpret_cast<struct linkedit_data_command *>(load_command);
 638                                 size = mach_header.Swap(signature->dataoff);
 639                                 _assert(size < mach_header.GetSize());
 640                                 break;
 641                             }
 642                         }
 643
 644                         if (size == _not(size_t))
 645                             size = mach_header.GetSize();
 646                     }
 647
 648                     allocations.push_back(CodesignAllocation(mach_header.GetCPUType(), mach_header.GetCPUSubtype(), size));
 649                 }
 650             }
 651
 652             pid_t pid = fork();
 653             _syscall(pid);
 654             if (pid == 0) {
 655                 // XXX: this leaks memory, but it doesn't really matter
 656                 std::vector<const char *> args;
 657                 char *arg;
 658
 659                 args.push_back(allocate);
 660
 661                 args.push_back("-i");
 662                 args.push_back(path);
 663
 664                 _foreach (allocation, allocations) {
 665                     args.push_back("-A");
 666
 667                     asprintf(&arg, "%u", allocation.type_);
 668                     args.push_back(arg);
 669
 670                     asprintf(&arg, "%u", allocation.subtype_);
 671                     args.push_back(arg);
 672
 673                     size_t alloc(0);
 674                     alloc += sizeof(struct SuperBlob);
 675                     uint32_t special(0);
 676
 677                     special = std::max(special, CSSLOT_CODEDIRECTORY);
 678                     alloc += sizeof(struct BlobIndex);
 679                     alloc += sizeof(struct CodeDirectory);
 680                     alloc += strlen(base) + 1;
 681
 682                     special = std::max(special, CSSLOT_REQUIREMENTS);
 683                     alloc += sizeof(struct BlobIndex);
 684                     alloc += 0xc;
 685
 686                     if (xmld != NULL) {
 687                         special = std::max(special, CSSLOT_ENTITLEMENTS);
 688                         alloc += sizeof(struct BlobIndex);
 689                         alloc += sizeof(struct Blob);
 690                         alloc += xmls;
 691                     }
 692
 693                     size_t normal((allocation.size_ + 0x1000 - 1) / 0x1000);
 694                     alloc += (special + normal) * 0x14;
 695
 696                     alloc += 15;
 697                     alloc /= 16;
 698                     alloc *= 16;
 699
 700                     asprintf(&arg, "%u", alloc);
 701                     args.push_back(arg);
 702                 }
 703
 704                 args.push_back("-o");
 705                 args.push_back(temp);
 706
 707                 args.push_back(NULL);
 708
 709                 if (false) {
 710                     printf("run:");
 711                     _foreach (arg, args)
 712                         printf(" %s", arg);
 713                     printf("\n");
 714                 }
 715
 716                 execvp(allocate, (char **) &args[0]);
 717                 _assert(false);
 718             }
 719
 720             int status;
 721             _syscall(waitpid(pid, &status, 0));
 722             _assert(WIFEXITED(status));
 723             _assert(WEXITSTATUS(status) == 0);
 724         }
 725
 726         if (flag_p)
 727             printf("path%zu='%s'\n", filei, file.c_str());
 728
 729         FatHeader fat_header(Map(temp == NULL ? path : temp));
 730         struct linkedit_data_command *signature(NULL);
 731
 732         _foreach (mach_header, fat_header.GetMachHeaders()) {
 733             if (woffset != _not(uintptr_t)) {
 734                 Pointer<uint32_t> wvalue(mach_header.GetPointer<uint32_t>(woffset));
 735                 if (wvalue == NULL)
 736                     printf("(null) %p\n", reinterpret_cast<void *>(woffset));
 737                 else
 738                     printf("0x%.08x\n", *wvalue);
 739             }
 740
 741             if (noffset != _not(uintptr_t))
 742                 printf("%s\n", &*mach_header.GetPointer<char>(noffset));
 743
 744             _foreach (load_command, mach_header.GetLoadCommands()) {
 745                 uint32_t cmd(mach_header.Swap(load_command->cmd));
 746
 747                 if (flag_R && cmd == LC_REEXPORT_DYLIB)
 748                     load_command->cmd = mach_header.Swap(LC_LOAD_DYLIB);
 749                 else if (cmd == LC_CODE_SIGNATURE)
 750                     signature = reinterpret_cast<struct linkedit_data_command *>(load_command);
 751                 else if (cmd == LC_UUID) {
 752                     volatile struct uuid_command *uuid_command(reinterpret_cast<struct uuid_command *>(load_command));
 753
 754                     if (flag_u) {
 755                         printf("uuid%zu=%.2x%.2x%.2x%.2x-%.2x%.2x-%.2x%.2x-%.2x%.2x-%.2x%.2x%.2x%.2x%.2x%.2x\n", filei,
 756                             uuid_command->uuid[ 0], uuid_command->uuid[ 1], uuid_command->uuid[ 2], uuid_command->uuid[ 3],
 757                             uuid_command->uuid[ 4], uuid_command->uuid[ 5], uuid_command->uuid[ 6], uuid_command->uuid[ 7],
 758                             uuid_command->uuid[ 8], uuid_command->uuid[ 9], uuid_command->uuid[10], uuid_command->uuid[11],
 759                             uuid_command->uuid[12], uuid_command->uuid[13], uuid_command->uuid[14], uuid_command->uuid[15]
 760                         );
 761                     }
 762                 } else if (cmd == LC_ID_DYLIB) {
 763                     volatile struct dylib_command *dylib_command(reinterpret_cast<struct dylib_command *>(load_command));
 764
 765                     if (flag_t)
 766                         printf("time%zu=0x%.8x\n", filei, mach_header.Swap(dylib_command->dylib.timestamp));
 767
 768                     if (flag_T) {
 769                         uint32_t timed;
 770
 771                         if (!timeh)
 772                             timed = timev;
 773                         else {
 774                             dylib_command->dylib.timestamp = 0;
 775                             timed = hash(reinterpret_cast<uint8_t *>(mach_header.GetBase()), mach_header.GetSize(), timev);
 776                         }
 777
 778                         dylib_command->dylib.timestamp = mach_header.Swap(timed);
 779                     }
 780                 }
 781             }
 782
 783             if (flag_e) {
 784                 _assert(signature != NULL);
 785
 786                 uint32_t data = mach_header.Swap(signature->dataoff);
 787                 uint32_t size = mach_header.Swap(signature->datasize);
 788
 789                 uint8_t *top = reinterpret_cast<uint8_t *>(mach_header.GetBase());
 790                 uint8_t *blob = top + data;
 791                 struct SuperBlob *super = reinterpret_cast<struct SuperBlob *>(blob);
 792
 793                 for (size_t index(0); index != Swap(super->count); ++index)
 794                     if (Swap(super->index[index].type) == CSSLOT_ENTITLEMENTS) {
 795                         uint32_t begin = Swap(super->index[index].offset);
 796                         struct Blob *entitlements = reinterpret_cast<struct Blob *>(blob + begin);
 797                         fwrite(entitlements + 1, 1, Swap(entitlements->length) - sizeof(struct Blob), stdout);
 798                     }
 799             }
 800
 801             if (flag_s) {
 802                 _assert(signature != NULL);
 803
 804                 uint32_t data = mach_header.Swap(signature->dataoff);
 805                 uint32_t size = mach_header.Swap(signature->datasize);
 806
 807                 uint8_t *top = reinterpret_cast<uint8_t *>(mach_header.GetBase());
 808                 uint8_t *blob = top + data;
 809                 struct SuperBlob *super = reinterpret_cast<struct SuperBlob *>(blob);
 810
 811                 for (size_t index(0); index != Swap(super->count); ++index)
 812                     if (Swap(super->index[index].type) == CSSLOT_CODEDIRECTORY) {
 813                         uint32_t begin = Swap(super->index[index].offset);
 814                         struct CodeDirectory *directory = reinterpret_cast<struct CodeDirectory *>(blob + begin);
 815
 816                         uint8_t (*hashes)[20] = reinterpret_cast<uint8_t (*)[20]>(blob + begin + Swap(directory->hashOffset));
 817                         uint32_t pages = Swap(directory->nCodeSlots);
 818
 819                         if (pages != 1)
 820                             for (size_t i = 0; i != pages - 1; ++i)
 821                                 sha1(hashes[i], top + 0x1000 * i, 0x1000);
 822                         if (pages != 0)
 823                             sha1(hashes[pages - 1], top + 0x1000 * (pages - 1), ((data - 1) % 0x1000) + 1);
 824                     }
 825             }
 826
 827             if (flag_S) {
 828                 _assert(signature != NULL);
 829
 830                 uint32_t data = mach_header.Swap(signature->dataoff);
 831                 uint32_t size = mach_header.Swap(signature->datasize);
 832
 833                 uint8_t *top = reinterpret_cast<uint8_t *>(mach_header.GetBase());
 834                 uint8_t *blob = top + data;
 835                 struct SuperBlob *super = reinterpret_cast<struct SuperBlob *>(blob);
 836                 super->blob.magic = Swap(CSMAGIC_EMBEDDED_SIGNATURE);
 837
 838                 uint32_t count = xmld == NULL ? 2 : 3;
 839                 uint32_t offset = sizeof(struct SuperBlob) + count * sizeof(struct BlobIndex);
 840
 841                 super->index[0].type = Swap(CSSLOT_CODEDIRECTORY);
 842                 super->index[0].offset = Swap(offset);
 843
 844                 uint32_t begin = offset;
 845                 struct CodeDirectory *directory = reinterpret_cast<struct CodeDirectory *>(blob + begin);
 846                 offset += sizeof(struct CodeDirectory);
 847
 848                 directory->blob.magic = Swap(CSMAGIC_CODEDIRECTORY);
 849                 directory->version = Swap(uint32_t(0x00020001));
 850                 directory->flags = Swap(uint32_t(0));
 851                 directory->codeLimit = Swap(data);
 852                 directory->hashSize = 0x14;
 853                 directory->hashType = 0x01;
 854                 directory->spare1 = 0x00;
 855                 directory->pageSize = 0x0c;
 856                 directory->spare2 = Swap(uint32_t(0));
 857
 858                 directory->identOffset = Swap(offset - begin);
 859                 strcpy(reinterpret_cast<char *>(blob + offset), base);
 860                 offset += strlen(base) + 1;
 861
 862                 uint32_t special = xmld == NULL ? CSSLOT_REQUIREMENTS : CSSLOT_ENTITLEMENTS;
 863                 directory->nSpecialSlots = Swap(special);
 864
 865                 uint8_t (*hashes)[20] = reinterpret_cast<uint8_t (*)[20]>(blob + offset);
 866                 memset(hashes, 0, sizeof(*hashes) * special);
 867
 868                 offset += sizeof(*hashes) * special;
 869                 hashes += special;
 870
 871                 uint32_t pages = (data + 0x1000 - 1) / 0x1000;
 872                 directory->nCodeSlots = Swap(pages);
 873
 874                 if (pages != 1)
 875                     for (size_t i = 0; i != pages - 1; ++i)
 876                         sha1(hashes[i], top + 0x1000 * i, 0x1000);
 877                 if (pages != 0)
 878                     sha1(hashes[pages - 1], top + 0x1000 * (pages - 1), ((data - 1) % 0x1000) + 1);
 879
 880                 directory->hashOffset = Swap(offset - begin);
 881                 offset += sizeof(*hashes) * pages;
 882                 directory->blob.length = Swap(offset - begin);
 883
 884                 super->index[1].type = Swap(CSSLOT_REQUIREMENTS);
 885                 super->index[1].offset = Swap(offset);
 886
 887                 memcpy(blob + offset, "\xfa\xde\x0c\x01\x00\x00\x00\x0c\x00\x00\x00\x00", 0xc);
 888                 offset += 0xc;
 889
 890                 if (xmld != NULL) {
 891                     super->index[2].type = Swap(CSSLOT_ENTITLEMENTS);
 892                     super->index[2].offset = Swap(offset);
 893
 894                     uint32_t begin = offset;
 895                     struct Blob *entitlements = reinterpret_cast<struct Blob *>(blob + begin);
 896                     offset += sizeof(struct Blob);
 897
 898                     memcpy(blob + offset, xmld, xmls);
 899                     offset += xmls;
 900
 901                     entitlements->magic = Swap(CSMAGIC_ENTITLEMENTS);
 902                     entitlements->length = Swap(offset - begin);
 903                 }
 904
 905                 for (size_t index(0); index != count; ++index) {
 906                     uint32_t type = Swap(super->index[index].type);
 907                     if (type != 0 && type <= special) {
 908                         uint32_t offset = Swap(super->index[index].offset);
 909                         struct Blob *local = (struct Blob *) (blob + offset);
 910                         sha1((uint8_t *) (hashes - type), (uint8_t *) local, Swap(local->length));
 911                     }
 912                 }
 913
 914                 super->count = Swap(count);
 915                 super->blob.length = Swap(offset);
 916
 917                 if (offset > size) {
 918                     fprintf(stderr, "offset (%u) > size (%u)\n", offset, size);
 919                     _assert(false);
 920                 } //else fprintf(stderr, "offset (%zu) <= size (%zu)\n", offset, size);
 921
 922                 memset(blob + offset, 0, size - offset);
 923             }
 924         }
 925
 926         if (flag_S) {
 927             uint8_t *top = reinterpret_cast<uint8_t *>(fat_header.GetBase());
 928             size_t size = fat_header.GetSize();
 929
 930             char *copy;
 931             asprintf(&copy, "%s.%s.cp", dir, base);
 932             FILE *file = fopen(copy, "w+");
 933             size_t writ = fwrite(top, 1, size, file);
 934             _assert(writ == size);
 935             fclose(file);
 936
 937             _syscall(unlink(temp));
 938             free(temp);
 939             temp = copy;
 940         }
 941
 942         if (temp != NULL) {
 943             struct stat info;
 944             _syscall(stat(path, &info));
 945             _syscall(chown(temp, info.st_uid, info.st_gid));
 946             _syscall(chmod(temp, info.st_mode));
 947             _syscall(unlink(path));
 948             _syscall(rename(temp, path));
 949             free(temp);
 950         }
 951
 952         free(dir);
 953         ++filei;
 954     } catch (const char *) {
 955         ++filee;
 956         ++filei;
 957     }
 958
 959     return filee;
 960 }