/* ldid - (Mach-O) Link-Loader Identity Editor * Copyright (C) 2007-2015 Jay Freeman (saurik) */ /* GNU Affero General Public License, Version 3 {{{ */ /* * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Affero General Public License for more details. * You should have received a copy of the GNU Affero General Public License * along with this program. If not, see . **/ /* }}} */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define _assert___(line) \ #line #define _assert__(line) \ _assert___(line) #define _assert_(e) \ throw __FILE__ "(" _assert__(__LINE__) "): _assert(" e ")" #define _assert(expr) \ do if (!(expr)) { \ fprintf(stderr, "%s(%u): _assert(%s); errno=%u\n", __FILE__, __LINE__, #expr, errno); \ _assert_(#expr); \ } while (false) #define _syscall(expr) ({ \ __typeof__(expr) _value; \ do if ((long) (_value = (expr)) != -1) \ break; \ else switch (errno) { \ case EINTR: \ continue; \ default: \ _assert(false); \ } while (true); \ _value; \ }) #define _trace() \ fprintf(stderr, "_trace(%s:%u): %s\n", __FILE__, __LINE__, __FUNCTION__) #define _not(type) \ ((type) ~ (type) 0) #define _packed \ __attribute__((packed)) template struct Iterator_ { typedef typename Type_::const_iterator Result; }; #define _foreach(item, list) \ for (bool _stop(true); _stop; ) \ for (const __typeof__(list) &_list = (list); _stop; _stop = false) \ for (Iterator_<__typeof__(list)>::Result _item = _list.begin(); _item != _list.end(); ++_item) \ for (bool _suck(true); _suck; _suck = false) \ for (const __typeof__(*_item) &item = *_item; _suck; _suck = false) struct fat_header { uint32_t magic; uint32_t nfat_arch; } _packed; #define FAT_MAGIC 0xcafebabe #define FAT_CIGAM 0xbebafeca struct fat_arch { uint32_t cputype; uint32_t cpusubtype; uint32_t offset; uint32_t size; uint32_t align; } _packed; struct mach_header { uint32_t magic; uint32_t cputype; uint32_t cpusubtype; uint32_t filetype; uint32_t ncmds; uint32_t sizeofcmds; uint32_t flags; } _packed; #define MH_MAGIC 0xfeedface #define MH_CIGAM 0xcefaedfe #define MH_MAGIC_64 0xfeedfacf #define MH_CIGAM_64 0xcffaedfe #define MH_DYLDLINK 0x4 #define MH_OBJECT 0x1 #define MH_EXECUTE 0x2 #define MH_DYLIB 0x6 #define MH_BUNDLE 0x8 #define MH_DYLIB_STUB 0x9 struct load_command { uint32_t cmd; uint32_t cmdsize; } _packed; #define LC_REQ_DYLD uint32_t(0x80000000) #define LC_SEGMENT uint32_t(0x01) #define LC_SYMTAB uint32_t(0x02) #define LC_DYSYMTAB uint32_t(0x0b) #define LC_LOAD_DYLIB uint32_t(0x0c) #define LC_ID_DYLIB uint32_t(0x0d) #define LC_SEGMENT_64 uint32_t(0x19) #define LC_UUID uint32_t(0x1b) #define LC_CODE_SIGNATURE uint32_t(0x1d) #define LC_SEGMENT_SPLIT_INFO uint32_t(0x1e) #define LC_REEXPORT_DYLIB uint32_t(0x1f | LC_REQ_DYLD) #define LC_ENCRYPTION_INFO uint32_t(0x21) #define LC_DYLD_INFO uint32_t(0x22) #define LC_DYLD_INFO_ONLY uint32_t(0x22 | LC_REQ_DYLD) #define LC_ENCRYPTION_INFO_64 uint32_t(0x2c) struct dylib { uint32_t name; uint32_t timestamp; uint32_t current_version; uint32_t compatibility_version; } _packed; struct dylib_command { uint32_t cmd; uint32_t cmdsize; struct dylib dylib; } _packed; struct uuid_command { uint32_t cmd; uint32_t cmdsize; uint8_t uuid[16]; } _packed; struct symtab_command { uint32_t cmd; uint32_t cmdsize; uint32_t symoff; uint32_t nsyms; uint32_t stroff; uint32_t strsize; } _packed; struct dyld_info_command { uint32_t cmd; uint32_t cmdsize; uint32_t rebase_off; uint32_t rebase_size; uint32_t bind_off; uint32_t bind_size; uint32_t weak_bind_off; uint32_t weak_bind_size; uint32_t lazy_bind_off; uint32_t lazy_bind_size; uint32_t export_off; uint32_t export_size; } _packed; struct dysymtab_command { uint32_t cmd; uint32_t cmdsize; uint32_t ilocalsym; uint32_t nlocalsym; uint32_t iextdefsym; uint32_t nextdefsym; uint32_t iundefsym; uint32_t nundefsym; uint32_t tocoff; uint32_t ntoc; uint32_t modtaboff; uint32_t nmodtab; uint32_t extrefsymoff; uint32_t nextrefsyms; uint32_t indirectsymoff; uint32_t nindirectsyms; uint32_t extreloff; uint32_t nextrel; uint32_t locreloff; uint32_t nlocrel; } _packed; struct dylib_table_of_contents { uint32_t symbol_index; uint32_t module_index; } _packed; struct dylib_module { uint32_t module_name; uint32_t iextdefsym; uint32_t nextdefsym; uint32_t irefsym; uint32_t nrefsym; uint32_t ilocalsym; uint32_t nlocalsym; uint32_t iextrel; uint32_t nextrel; uint32_t iinit_iterm; uint32_t ninit_nterm; uint32_t objc_module_info_addr; uint32_t objc_module_info_size; } _packed; struct dylib_reference { uint32_t isym:24; uint32_t flags:8; } _packed; struct relocation_info { int32_t r_address; uint32_t r_symbolnum:24; uint32_t r_pcrel:1; uint32_t r_length:2; uint32_t r_extern:1; uint32_t r_type:4; } _packed; struct nlist { union { char *n_name; int32_t n_strx; } n_un; uint8_t n_type; uint8_t n_sect; uint8_t n_desc; uint32_t n_value; } _packed; struct segment_command { uint32_t cmd; uint32_t cmdsize; char segname[16]; uint32_t vmaddr; uint32_t vmsize; uint32_t fileoff; uint32_t filesize; uint32_t maxprot; uint32_t initprot; uint32_t nsects; uint32_t flags; } _packed; struct segment_command_64 { uint32_t cmd; uint32_t cmdsize; char segname[16]; uint64_t vmaddr; uint64_t vmsize; uint64_t fileoff; uint64_t filesize; uint32_t maxprot; uint32_t initprot; uint32_t nsects; uint32_t flags; } _packed; struct section { char sectname[16]; char segname[16]; uint32_t addr; uint32_t size; uint32_t offset; uint32_t align; uint32_t reloff; uint32_t nreloc; uint32_t flags; uint32_t reserved1; uint32_t reserved2; } _packed; struct section_64 { char sectname[16]; char segname[16]; uint64_t addr; uint64_t size; uint32_t offset; uint32_t align; uint32_t reloff; uint32_t nreloc; uint32_t flags; uint32_t reserved1; uint32_t reserved2; } _packed; struct linkedit_data_command { uint32_t cmd; uint32_t cmdsize; uint32_t dataoff; uint32_t datasize; } _packed; struct encryption_info_command { uint32_t cmd; uint32_t cmdsize; uint32_t cryptoff; uint32_t cryptsize; uint32_t cryptid; } _packed; #define BIND_OPCODE_MASK 0xf0 #define BIND_IMMEDIATE_MASK 0x0f #define BIND_OPCODE_DONE 0x00 #define BIND_OPCODE_SET_DYLIB_ORDINAL_IMM 0x10 #define BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB 0x20 #define BIND_OPCODE_SET_DYLIB_SPECIAL_IMM 0x30 #define BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM 0x40 #define BIND_OPCODE_SET_TYPE_IMM 0x50 #define BIND_OPCODE_SET_ADDEND_SLEB 0x60 #define BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB 0x70 #define BIND_OPCODE_ADD_ADDR_ULEB 0x80 #define BIND_OPCODE_DO_BIND 0x90 #define BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB 0xa0 #define BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED 0xb0 #define BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB 0xc0 inline void get(std::streambuf &stream, void *data, size_t size) { _assert(stream.sgetn(static_cast(data), size) == size); } inline void put(std::streambuf &stream, const void *data, size_t size) { _assert(stream.sputn(static_cast(data), size) == size); } inline void pad(std::streambuf &stream, size_t size) { char padding[size]; memset(padding, 0, size); put(stream, padding, size); } template Type_ Align(Type_ value, size_t align) { value += align - 1; value /= align; value *= align; return value; } uint16_t Swap_(uint16_t value) { return ((value >> 8) & 0x00ff) | ((value << 8) & 0xff00); } uint32_t Swap_(uint32_t value) { value = ((value >> 8) & 0x00ff00ff) | ((value << 8) & 0xff00ff00); value = ((value >> 16) & 0x0000ffff) | ((value << 16) & 0xffff0000); return value; } uint64_t Swap_(uint64_t value) { value = (value & 0x00000000ffffffff) << 32 | (value & 0xffffffff00000000) >> 32; value = (value & 0x0000ffff0000ffff) << 16 | (value & 0xffff0000ffff0000) >> 16; value = (value & 0x00ff00ff00ff00ff) << 8 | (value & 0xff00ff00ff00ff00) >> 8; return value; } int16_t Swap_(int16_t value) { return Swap_(static_cast(value)); } int32_t Swap_(int32_t value) { return Swap_(static_cast(value)); } int64_t Swap_(int64_t value) { return Swap_(static_cast(value)); } bool little_(true); uint16_t Swap(uint16_t value) { return little_ ? Swap_(value) : value; } uint32_t Swap(uint32_t value) { return little_ ? Swap_(value) : value; } uint64_t Swap(uint64_t value) { return little_ ? Swap_(value) : value; } int16_t Swap(int16_t value) { return Swap(static_cast(value)); } int32_t Swap(int32_t value) { return Swap(static_cast(value)); } int64_t Swap(int64_t value) { return Swap(static_cast(value)); } template class Pointer; class Swapped { protected: bool swapped_; Swapped() : swapped_(false) { } public: Swapped(bool swapped) : swapped_(swapped) { } template Type_ Swap(Type_ value) const { return swapped_ ? Swap_(value) : value; } }; class Data : public Swapped { private: void *base_; size_t size_; public: Data(void *base, size_t size) : base_(base), size_(size) { } void *GetBase() const { return base_; } size_t GetSize() const { return size_; } }; class MachHeader : public Data { private: bool bits64_; struct mach_header *mach_header_; struct load_command *load_command_; public: MachHeader(void *base, size_t size) : Data(base, size) { mach_header_ = (mach_header *) base; switch (Swap(mach_header_->magic)) { case MH_CIGAM: swapped_ = !swapped_; case MH_MAGIC: bits64_ = false; break; case MH_CIGAM_64: swapped_ = !swapped_; case MH_MAGIC_64: bits64_ = true; break; default: _assert(false); } void *post = mach_header_ + 1; if (bits64_) post = (uint32_t *) post + 1; load_command_ = (struct load_command *) post; _assert( Swap(mach_header_->filetype) == MH_EXECUTE || Swap(mach_header_->filetype) == MH_DYLIB || Swap(mach_header_->filetype) == MH_BUNDLE ); } bool Bits64() const { return bits64_; } struct mach_header *operator ->() const { return mach_header_; } operator struct mach_header *() const { return mach_header_; } uint32_t GetCPUType() const { return Swap(mach_header_->cputype); } uint32_t GetCPUSubtype() const { return Swap(mach_header_->cpusubtype) & 0xff; } struct load_command *GetLoadCommand() const { return load_command_; } std::vector GetLoadCommands() const { std::vector load_commands; struct load_command *load_command = load_command_; for (uint32_t cmd = 0; cmd != Swap(mach_header_->ncmds); ++cmd) { load_commands.push_back(load_command); load_command = (struct load_command *) ((uint8_t *) load_command + Swap(load_command->cmdsize)); } return load_commands; } std::vector GetSegments(const char *segment_name) const { std::vector segment_commands; _foreach (load_command, GetLoadCommands()) { if (Swap(load_command->cmd) == LC_SEGMENT) { segment_command *segment_command = reinterpret_cast(load_command); if (strncmp(segment_command->segname, segment_name, 16) == 0) segment_commands.push_back(segment_command); } } return segment_commands; } std::vector GetSegments64(const char *segment_name) const { std::vector segment_commands; _foreach (load_command, GetLoadCommands()) { if (Swap(load_command->cmd) == LC_SEGMENT_64) { segment_command_64 *segment_command = reinterpret_cast(load_command); if (strncmp(segment_command->segname, segment_name, 16) == 0) segment_commands.push_back(segment_command); } } return segment_commands; } std::vector
GetSections(const char *segment_name, const char *section_name) const { std::vector
sections; _foreach (segment, GetSegments(segment_name)) { section *section = (struct section *) (segment + 1); uint32_t sect; for (sect = 0; sect != Swap(segment->nsects); ++sect) { if (strncmp(section->sectname, section_name, 16) == 0) sections.push_back(section); ++section; } } return sections; } template Pointer GetPointer(uint32_t address, const char *segment_name = NULL) const { load_command *load_command = (struct load_command *) (mach_header_ + 1); uint32_t cmd; for (cmd = 0; cmd != Swap(mach_header_->ncmds); ++cmd) { if (Swap(load_command->cmd) == LC_SEGMENT) { segment_command *segment_command = (struct segment_command *) load_command; if (segment_name != NULL && strncmp(segment_command->segname, segment_name, 16) != 0) goto next_command; section *sections = (struct section *) (segment_command + 1); uint32_t sect; for (sect = 0; sect != Swap(segment_command->nsects); ++sect) { section *section = §ions[sect]; //printf("%s %u %p %p %u\n", segment_command->segname, sect, address, section->addr, section->size); if (address >= Swap(section->addr) && address < Swap(section->addr) + Swap(section->size)) { //printf("0x%.8x %s\n", address, segment_command->segname); return Pointer(this, reinterpret_cast(address - Swap(section->addr) + Swap(section->offset) + (char *) mach_header_)); } } } next_command: load_command = (struct load_command *) ((char *) load_command + Swap(load_command->cmdsize)); } return Pointer(this); } template Pointer GetOffset(uint32_t offset) { return Pointer(this, reinterpret_cast(offset + (uint8_t *) mach_header_)); } }; class FatMachHeader : public MachHeader { private: fat_arch *fat_arch_; public: FatMachHeader(void *base, size_t size, fat_arch *fat_arch) : MachHeader(base, size), fat_arch_(fat_arch) { } fat_arch *GetFatArch() const { return fat_arch_; } }; class FatHeader : public Data { private: fat_header *fat_header_; std::vector mach_headers_; public: FatHeader(void *base, size_t size) : Data(base, size) { fat_header_ = reinterpret_cast(base); if (Swap(fat_header_->magic) == FAT_CIGAM) { swapped_ = !swapped_; goto fat; } else if (Swap(fat_header_->magic) != FAT_MAGIC) { fat_header_ = NULL; mach_headers_.push_back(FatMachHeader(base, size, NULL)); } else fat: { size_t fat_narch = Swap(fat_header_->nfat_arch); fat_arch *fat_arch = reinterpret_cast(fat_header_ + 1); size_t arch; for (arch = 0; arch != fat_narch; ++arch) { uint32_t arch_offset = Swap(fat_arch->offset); uint32_t arch_size = Swap(fat_arch->size); mach_headers_.push_back(FatMachHeader((uint8_t *) base + arch_offset, arch_size, fat_arch)); ++fat_arch; } } } std::vector &GetMachHeaders() { return mach_headers_; } bool IsFat() const { return fat_header_ != NULL; } struct fat_header *operator ->() const { return fat_header_; } operator struct fat_header *() const { return fat_header_; } }; template class Pointer { private: const MachHeader *framework_; const Target_ *pointer_; public: Pointer(const MachHeader *framework = NULL, const Target_ *pointer = NULL) : framework_(framework), pointer_(pointer) { } operator const Target_ *() const { return pointer_; } const Target_ *operator ->() const { return pointer_; } Pointer &operator ++() { ++pointer_; return *this; } template Value_ Swap(Value_ value) { return framework_->Swap(value); } }; #define CSMAGIC_REQUIREMENT uint32_t(0xfade0c00) #define CSMAGIC_REQUIREMENTS uint32_t(0xfade0c01) #define CSMAGIC_CODEDIRECTORY uint32_t(0xfade0c02) #define CSMAGIC_EMBEDDED_SIGNATURE uint32_t(0xfade0cc0) #define CSMAGIC_EMBEDDED_SIGNATURE_OLD uint32_t(0xfade0b02) #define CSMAGIC_EMBEDDED_ENTITLEMENTS uint32_t(0xfade7171) #define CSMAGIC_DETACHED_SIGNATURE uint32_t(0xfade0cc1) #define CSMAGIC_BLOBWRAPPER uint32_t(0xfade0b01) #define CSSLOT_CODEDIRECTORY uint32_t(0x00000) #define CSSLOT_INFOSLOT uint32_t(0x00001) #define CSSLOT_REQUIREMENTS uint32_t(0x00002) #define CSSLOT_RESOURCEDIR uint32_t(0x00003) #define CSSLOT_APPLICATION uint32_t(0x00004) #define CSSLOT_ENTITLEMENTS uint32_t(0x00005) #define CSSLOT_SIGNATURESLOT uint32_t(0x10000) #define CS_HASHTYPE_SHA1 1 struct BlobIndex { uint32_t type; uint32_t offset; } _packed; struct Blob { uint32_t magic; uint32_t length; } _packed; struct SuperBlob { struct Blob blob; uint32_t count; struct BlobIndex index[]; } _packed; struct CodeDirectory { uint32_t version; uint32_t flags; uint32_t hashOffset; uint32_t identOffset; uint32_t nSpecialSlots; uint32_t nCodeSlots; uint32_t codeLimit; uint8_t hashSize; uint8_t hashType; uint8_t spare1; uint8_t pageSize; uint32_t spare2; } _packed; extern "C" uint32_t hash(uint8_t *k, uint32_t length, uint32_t initval); void sha1(uint8_t *hash, const void *data, size_t size) { SHA1(static_cast(data), size, hash); } struct CodesignAllocation { FatMachHeader mach_header_; uint32_t offset_; uint32_t size_; uint32_t limit_; uint32_t alloc_; uint32_t align_; CodesignAllocation(FatMachHeader mach_header, size_t offset, size_t size, size_t limit, size_t alloc, size_t align) : mach_header_(mach_header), offset_(offset), size_(size), limit_(limit), alloc_(alloc), align_(align) { } }; class File { private: int file_; public: File() : file_(-1) { } ~File() { if (file_ != -1) _syscall(close(file_)); } void open(const char *path, int flags) { _assert(file_ == -1); _syscall(file_ = ::open(path, flags)); } int file() const { return file_; } }; class Map { private: File file_; void *data_; size_t size_; void clear() { if (data_ == NULL) return; _syscall(munmap(data_, size_)); data_ = NULL; size_ = 0; } public: Map() : data_(NULL), size_(0) { } Map(const char *path, int oflag, int pflag, int mflag) : Map() { open(path, oflag, pflag, mflag); } Map(const char *path, bool edit) : Map() { open(path, edit); } ~Map() { clear(); } void open(const char *path, int oflag, int pflag, int mflag) { clear(); file_.open(path, oflag); int file(file_.file()); struct stat stat; _syscall(fstat(file, &stat)); size_ = stat.st_size; _syscall(data_ = mmap(NULL, size_, pflag, mflag, file, 0)); } void open(const char *path, bool edit) { if (edit) open(path, O_RDWR, PROT_READ | PROT_WRITE, MAP_SHARED); else open(path, O_RDONLY, PROT_READ, MAP_PRIVATE); } void *data() const { return data_; } size_t size() const { return size_; } operator std::string() const { return std::string(static_cast(data_), size_); } }; // I wish Apple cared about providing quality toolchains :/ template class Functor; template class Functor { public: virtual Type_ operator ()(Args_... args) const = 0; }; template class FunctorImpl; template class FunctorImpl : public Functor { private: const Value_ *value_; public: FunctorImpl() : value_(NULL) { } FunctorImpl(const Value_ &value) : value_(&value) { } virtual Type_ operator ()(Args_... args) const { return (*value_)(args...); } }; template FunctorImpl fun(const Function_ &value) { return value; } void resign(void *idata, size_t isize, std::streambuf &output, const Functor &allocate, const Functor &save) { FatHeader source(idata, isize); size_t offset(0); if (source.IsFat()) offset += sizeof(fat_header) + sizeof(fat_arch) * source.Swap(source->nfat_arch); std::vector allocations; _foreach (mach_header, source.GetMachHeaders()) { struct linkedit_data_command *signature(NULL); struct symtab_command *symtab(NULL); _foreach (load_command, mach_header.GetLoadCommands()) { uint32_t cmd(mach_header.Swap(load_command->cmd)); if (false); else if (cmd == LC_CODE_SIGNATURE) signature = reinterpret_cast(load_command); else if (cmd == LC_SYMTAB) symtab = reinterpret_cast(load_command); } size_t size; if (signature == NULL) size = mach_header.GetSize(); else { size = mach_header.Swap(signature->dataoff); _assert(size <= mach_header.GetSize()); } if (symtab != NULL) { auto end(mach_header.Swap(symtab->stroff) + mach_header.Swap(symtab->strsize)); _assert(end <= size); _assert(end >= size - 0x10); size = end; } size_t alloc(allocate(size)); auto *fat_arch(mach_header.GetFatArch()); uint32_t align(fat_arch == NULL ? 0 : source.Swap(fat_arch->align)); offset = Align(offset, 1 << align); uint32_t limit(size); if (alloc != 0) limit = Align(limit, 0x10); allocations.push_back(CodesignAllocation(mach_header, offset, size, limit, alloc, align)); offset += size + alloc; offset = Align(offset, 16); } size_t position(0); if (source.IsFat()) { fat_header fat_header; fat_header.magic = Swap(FAT_MAGIC); fat_header.nfat_arch = Swap(uint32_t(allocations.size())); put(output, &fat_header, sizeof(fat_header)); position += sizeof(fat_header); _foreach (allocation, allocations) { auto &mach_header(allocation.mach_header_); fat_arch fat_arch; fat_arch.cputype = Swap(mach_header->cputype); fat_arch.cpusubtype = Swap(mach_header->cpusubtype); fat_arch.offset = Swap(allocation.offset_); fat_arch.size = Swap(allocation.limit_ + allocation.alloc_); fat_arch.align = Swap(allocation.align_); put(output, &fat_arch, sizeof(fat_arch)); position += sizeof(fat_arch); } } _foreach (allocation, allocations) { auto &mach_header(allocation.mach_header_); pad(output, allocation.offset_ - position); position = allocation.offset_; std::vector commands; _foreach (load_command, mach_header.GetLoadCommands()) { std::string copy(reinterpret_cast(load_command), load_command->cmdsize); switch (mach_header.Swap(load_command->cmd)) { case LC_CODE_SIGNATURE: continue; break; case LC_SEGMENT: { auto segment_command(reinterpret_cast(©[0])); if (strncmp(segment_command->segname, "__LINKEDIT", 16) != 0) break; size_t size(mach_header.Swap(allocation.limit_ + allocation.alloc_ - mach_header.Swap(segment_command->fileoff))); segment_command->filesize = size; segment_command->vmsize = Align(size, 0x1000); } break; case LC_SEGMENT_64: { auto segment_command(reinterpret_cast(©[0])); if (strncmp(segment_command->segname, "__LINKEDIT", 16) != 0) break; size_t size(mach_header.Swap(allocation.limit_ + allocation.alloc_ - mach_header.Swap(segment_command->fileoff))); segment_command->filesize = size; segment_command->vmsize = Align(size, 0x1000); } break; } commands.push_back(copy); } if (allocation.alloc_ != 0) { linkedit_data_command signature; signature.cmd = mach_header.Swap(LC_CODE_SIGNATURE); signature.cmdsize = mach_header.Swap(uint32_t(sizeof(signature))); signature.dataoff = mach_header.Swap(allocation.limit_); signature.datasize = mach_header.Swap(allocation.alloc_); commands.push_back(std::string(reinterpret_cast(&signature), sizeof(signature))); } size_t begin(position); uint32_t after(0); _foreach(command, commands) after += command.size(); std::stringbuf altern; struct mach_header header(*mach_header); header.ncmds = mach_header.Swap(uint32_t(commands.size())); header.sizeofcmds = mach_header.Swap(after); put(output, &header, sizeof(header)); put(altern, &header, sizeof(header)); position += sizeof(header); if (mach_header.Bits64()) { auto pad(mach_header.Swap(uint32_t(0))); put(output, &pad, sizeof(pad)); put(altern, &pad, sizeof(pad)); position += sizeof(pad); } _foreach(command, commands) { put(output, command.data(), command.size()); put(altern, command.data(), command.size()); position += command.size(); } uint32_t before(mach_header.Swap(mach_header->sizeofcmds)); if (before > after) { pad(output, before - after); pad(altern, before - after); position += before - after; } auto top(reinterpret_cast(mach_header.GetBase())); std::string overlap(altern.str()); overlap.append(top + overlap.size(), Align(overlap.size(), 0x1000) - overlap.size()); put(output, top + (position - begin), allocation.size_ - (position - begin)); position = begin + allocation.size_; pad(output, allocation.limit_ - allocation.size_); position += allocation.limit_ - allocation.size_; size_t saved(save(output, allocation.limit_, overlap, top)); if (allocation.alloc_ > saved) pad(output, allocation.alloc_ - saved); position += allocation.alloc_; } } typedef std::map Blobs; static void insert(Blobs &blobs, uint32_t slot, const std::stringbuf &buffer) { auto value(buffer.str()); std::swap(blobs[slot], value); } static void insert(Blobs &blobs, uint32_t slot, uint32_t magic, const std::stringbuf &buffer) { auto value(buffer.str()); Blob blob; blob.magic = Swap(magic); blob.length = Swap(uint32_t(sizeof(blob) + value.size())); value.insert(0, reinterpret_cast(&blob), sizeof(blob)); std::swap(blobs[slot], value); } static size_t put(std::streambuf &output, uint32_t magic, const Blobs &blobs) { size_t total(0); _foreach (blob, blobs) total += blob.second.size(); struct SuperBlob super; super.blob.magic = Swap(magic); super.blob.length = Swap(uint32_t(sizeof(SuperBlob) + blobs.size() * sizeof(BlobIndex) + total)); super.count = Swap(uint32_t(blobs.size())); put(output, &super, sizeof(super)); size_t offset(sizeof(SuperBlob) + sizeof(BlobIndex) * blobs.size()); _foreach (blob, blobs) { BlobIndex index; index.type = Swap(blob.first); index.offset = Swap(uint32_t(offset)); put(output, &index, sizeof(index)); offset += blob.second.size(); } _foreach (blob, blobs) put(output, blob.second.data(), blob.second.size()); return offset; } void resign(void *idata, size_t isize, std::streambuf &output, const std::string &name, const std::string &entitlements) { uint8_t pageshift(0x0c); uint32_t pagesize(1 << pageshift); resign(idata, isize, output, fun([&](size_t size) -> size_t { size_t alloc(sizeof(struct SuperBlob)); uint32_t special(0); special = std::max(special, CSSLOT_REQUIREMENTS); alloc += sizeof(struct BlobIndex); alloc += 0xc; if (entitlements.size() != 0) { special = std::max(special, CSSLOT_ENTITLEMENTS); alloc += sizeof(struct BlobIndex); alloc += sizeof(struct Blob); alloc += entitlements.size(); } special = std::max(special, CSSLOT_CODEDIRECTORY); alloc += sizeof(struct BlobIndex); alloc += sizeof(struct Blob); alloc += sizeof(struct CodeDirectory); alloc += name.size() + 1; uint32_t normal((size + pagesize - 1) / pagesize); alloc = Align(alloc + (special + normal) * SHA_DIGEST_LENGTH, 16); return alloc; }), fun([&](std::streambuf &output, size_t limit, const std::string &overlap, const char *top) -> size_t { Blobs blobs; if (true) { std::stringbuf data; Blobs requirements; put(data, CSMAGIC_REQUIREMENTS, requirements); insert(blobs, CSSLOT_REQUIREMENTS, data); } if (entitlements.size() != 0) { std::stringbuf data; put(data, entitlements.data(), entitlements.size()); insert(blobs, CSSLOT_ENTITLEMENTS, CSMAGIC_EMBEDDED_ENTITLEMENTS, data); } if (true) { std::stringbuf data; uint32_t special(0); _foreach (blob, blobs) special = std::max(special, blob.first); uint32_t normal((limit + pagesize - 1) / pagesize); CodeDirectory directory; directory.version = Swap(uint32_t(0x00020001)); directory.flags = Swap(uint32_t(0)); directory.hashOffset = Swap(uint32_t(sizeof(Blob) + sizeof(CodeDirectory) + name.size() + 1 + SHA_DIGEST_LENGTH * special)); directory.identOffset = Swap(uint32_t(sizeof(Blob) + sizeof(CodeDirectory))); directory.nSpecialSlots = Swap(special); directory.codeLimit = Swap(uint32_t(limit)); directory.nCodeSlots = Swap(normal); directory.hashSize = SHA_DIGEST_LENGTH; directory.hashType = CS_HASHTYPE_SHA1; directory.spare1 = 0x00; directory.pageSize = pageshift; directory.spare2 = Swap(uint32_t(0)); put(data, &directory, sizeof(directory)); put(data, name.c_str(), name.size() + 1); uint8_t storage[special + normal][SHA_DIGEST_LENGTH]; uint8_t (*hashes)[SHA_DIGEST_LENGTH] = storage + special; memset(storage, 0, sizeof(*storage) * special); _foreach (blob, blobs) { auto local(reinterpret_cast(&blob.second[0])); sha1((uint8_t *) (hashes - blob.first), local, Swap(local->length)); } if (normal != 1) for (size_t i = 0; i != normal - 1; ++i) sha1(hashes[i], (pagesize * i < overlap.size() ? overlap.data() : top) + pagesize * i, pagesize); if (normal != 0) sha1(hashes[normal - 1], top + pagesize * (normal - 1), ((limit - 1) % pagesize) + 1); put(data, storage, sizeof(storage)); insert(blobs, CSSLOT_CODEDIRECTORY, CSMAGIC_CODEDIRECTORY, data); } return put(output, CSMAGIC_EMBEDDED_SIGNATURE, blobs); })); } void resign(void *idata, size_t isize, std::streambuf &output) { resign(idata, isize, output, fun([](size_t size) -> size_t { return 0; }), fun([](std::streambuf &output, size_t limit, const std::string &overlap, const char *top) -> size_t { return 0; })); } int main(int argc, char *argv[]) { union { uint16_t word; uint8_t byte[2]; } endian = {1}; little_ = endian.byte[0]; bool flag_r(false); bool flag_e(false); bool flag_T(false); bool flag_S(false); bool flag_s(false); bool flag_D(false); bool flag_A(false); bool flag_a(false); uint32_t flag_CPUType(_not(uint32_t)); uint32_t flag_CPUSubtype(_not(uint32_t)); const char *flag_I(NULL); bool timeh(false); uint32_t timev(0); Map entitlements; std::vector files; if (argc == 1) { fprintf(stderr, "usage: %s -S[entitlements.xml] \n", argv[0]); fprintf(stderr, " %s -e MobileSafari\n", argv[0]); fprintf(stderr, " %s -S cat\n", argv[0]); fprintf(stderr, " %s -Stfp.xml gdb\n", argv[0]); exit(0); } for (int argi(1); argi != argc; ++argi) if (argv[argi][0] != '-') files.push_back(argv[argi]); else switch (argv[argi][1]) { case 'r': flag_r = true; break; case 'e': flag_e = true; break; case 'D': flag_D = true; break; case 'a': flag_a = true; break; case 'A': flag_A = true; if (argv[argi][2] != '\0') { const char *cpu = argv[argi] + 2; const char *colon = strchr(cpu, ':'); _assert(colon != NULL); char *arge; flag_CPUType = strtoul(cpu, &arge, 0); _assert(arge == colon); flag_CPUSubtype = strtoul(colon + 1, &arge, 0); _assert(arge == argv[argi] + strlen(argv[argi])); } break; case 's': _assert(!flag_S); flag_s = true; break; case 'S': _assert(!flag_s); flag_S = true; if (argv[argi][2] != '\0') { const char *xml = argv[argi] + 2; entitlements.open(xml, O_RDONLY, PROT_READ, MAP_PRIVATE); } break; case 'T': { flag_T = true; if (argv[argi][2] == '-') timeh = true; else { char *arge; timev = strtoul(argv[argi] + 2, &arge, 0); _assert(arge == argv[argi] + strlen(argv[argi])); } } break; case 'I': { flag_I = argv[argi] + 2; } break; default: goto usage; break; } _assert(!flag_S || !flag_r); if (files.empty()) usage: { exit(0); } size_t filei(0), filee(0); _foreach (file, files) try { const char *path(file.c_str()); const char *base = strrchr(path, '/'); std::string dir; if (base != NULL) dir.assign(path, base++ - path + 1); else base = path; const char *name(flag_I ?: base); std::string temp; if (flag_S || flag_r) { Map input(path, O_RDONLY, PROT_READ, MAP_PRIVATE); temp = dir + "." + base + ".cs"; std::filebuf output; _assert(output.open(temp.c_str(), std::ios::out | std::ios::trunc | std::ios::binary) == &output); if (flag_r) resign(input.data(), input.size(), output); else { resign(input.data(), input.size(), output, name, entitlements); } } Map mapping(!temp.empty() ? temp.c_str() : path, flag_T || flag_s); FatHeader fat_header(mapping.data(), mapping.size()); _foreach (mach_header, fat_header.GetMachHeaders()) { struct linkedit_data_command *signature(NULL); struct encryption_info_command *encryption(NULL); if (flag_A) { if (mach_header.GetCPUType() != flag_CPUType) continue; if (mach_header.GetCPUSubtype() != flag_CPUSubtype) continue; } if (flag_a) printf("cpu=0x%x:0x%x\n", mach_header.GetCPUType(), mach_header.GetCPUSubtype()); _foreach (load_command, mach_header.GetLoadCommands()) { uint32_t cmd(mach_header.Swap(load_command->cmd)); if (false); else if (cmd == LC_CODE_SIGNATURE) signature = reinterpret_cast(load_command); else if (cmd == LC_ENCRYPTION_INFO || cmd == LC_ENCRYPTION_INFO_64) encryption = reinterpret_cast(load_command); else if (cmd == LC_ID_DYLIB) { volatile struct dylib_command *dylib_command(reinterpret_cast(load_command)); if (flag_T) { uint32_t timed; if (!timeh) timed = timev; else { dylib_command->dylib.timestamp = 0; timed = hash(reinterpret_cast(mach_header.GetBase()), mach_header.GetSize(), timev); } dylib_command->dylib.timestamp = mach_header.Swap(timed); } } } if (flag_D) { _assert(encryption != NULL); encryption->cryptid = mach_header.Swap(0); } if (flag_e) { _assert(signature != NULL); uint32_t data = mach_header.Swap(signature->dataoff); uint8_t *top = reinterpret_cast(mach_header.GetBase()); uint8_t *blob = top + data; struct SuperBlob *super = reinterpret_cast(blob); for (size_t index(0); index != Swap(super->count); ++index) if (Swap(super->index[index].type) == CSSLOT_ENTITLEMENTS) { uint32_t begin = Swap(super->index[index].offset); struct Blob *entitlements = reinterpret_cast(blob + begin); fwrite(entitlements + 1, 1, Swap(entitlements->length) - sizeof(struct Blob), stdout); } } if (flag_s) { _assert(signature != NULL); uint32_t data = mach_header.Swap(signature->dataoff); uint8_t *top = reinterpret_cast(mach_header.GetBase()); uint8_t *blob = top + data; struct SuperBlob *super = reinterpret_cast(blob); for (size_t index(0); index != Swap(super->count); ++index) if (Swap(super->index[index].type) == CSSLOT_CODEDIRECTORY) { uint32_t begin = Swap(super->index[index].offset); struct CodeDirectory *directory = reinterpret_cast(blob + begin); uint8_t (*hashes)[SHA_DIGEST_LENGTH] = reinterpret_cast(blob + begin + Swap(directory->hashOffset)); uint32_t pages = Swap(directory->nCodeSlots); if (pages != 1) for (size_t i = 0; i != pages - 1; ++i) sha1(hashes[i], top + 0x1000 * i, 0x1000); if (pages != 0) sha1(hashes[pages - 1], top + 0x1000 * (pages - 1), ((data - 1) % 0x1000) + 1); } } } if (!temp.empty()) { struct stat info; _syscall(stat(path, &info)); #ifndef __WIN32__ _syscall(chown(temp.c_str(), info.st_uid, info.st_gid)); #endif _syscall(chmod(temp.c_str(), info.st_mode)); _syscall(unlink(path)); _syscall(rename(temp.c_str(), path)); } ++filei; } catch (const char *) { ++filee; ++filei; } return filee; }