// Copyright (c) 2006, Google Inc. // All rights reserved. // // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are // met: // // * Redistributions of source code must retain the above copyright // notice, this list of conditions and the following disclaimer. // * Redistributions in binary form must reproduce the above // copyright notice, this list of conditions and the following disclaimer // in the documentation and/or other materials provided with the // distribution. // * Neither the name of Google Inc. nor the names of its // contributors may be used to endorse or promote products derived from // this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. // macho_walker.h: Iterate over the load commands in a mach-o file // // Author: Dan Waylonis #ifndef COMMON_MAC_MACHO_WALKER_H__ #define COMMON_MAC_MACHO_WALKER_H__ #include <mach-o/loader.h> #include <sys/types.h> namespace MacFileUtilities { class MachoWalker { public: // A callback function executed when a new load command is read. If no // further processing of load commands is desired, return false. Otherwise, // return true. // |cmd| is the current command, and |offset| is the location relative to the // beginning of the file (not header) where the command was read. If |swap| // is set, then any command data (other than the returned load_command) should // be swapped when read typedef bool (*LoadCommandCallback)(MachoWalker *walker, load_command *cmd, off_t offset, bool swap, void *context); MachoWalker(const char *path, LoadCommandCallback callback, void *context); MachoWalker(void *memory, size_t size, LoadCommandCallback callback, void *context); ~MachoWalker(); // Begin walking the header for |cpu_type|. If |cpu_type| is 0, then the // native cpu type is used. Otherwise, accepted values are listed in // /usr/include/mach/machine.h (e.g., CPU_TYPE_X86 or CPU_TYPE_POWERPC). // Returns false if opening the file failed or if the |cpu_type| is not // present in the file. bool WalkHeader(int cpu_type); // Locate (if any) the header offset for |cpu_type| and return in |offset|. // Return true if found, false otherwise. bool FindHeader(int cpu_type, off_t &offset); // Read |size| bytes from the opened file at |offset| into |buffer| bool ReadBytes(void *buffer, size_t size, off_t offset); // Return the current header and header offset bool CurrentHeader(struct mach_header_64 *header, off_t *offset); private: // Validate the |cpu_type| int ValidateCPUType(int cpu_type); // Process an individual header starting at |offset| from the start of the // file. Return true if successful, false otherwise. bool WalkHeaderAtOffset(off_t offset); bool WalkHeader64AtOffset(off_t offset); // Bottleneck for walking the load commands bool WalkHeaderCore(off_t offset, uint32_t number_of_commands, bool swap); // File descriptor to the opened file int file_; // Memory location to read from. void *memory_; // Size of the memory segment we can read from. size_t memory_size_; // User specified callback & context LoadCommandCallback callback_; void *callback_context_; // Current header, size, and offset. The mach_header_64 is used for both // 32-bit and 64-bit headers because they only differ in their last field // (reserved). By adding the |current_header_size_| and the // |current_header_offset_|, you can determine the offset in the file just // after the header. struct mach_header_64 *current_header_; unsigned long current_header_size_; off_t current_header_offset_; private: MachoWalker(const MachoWalker &); MachoWalker &operator=(const MachoWalker &); }; } // namespace MacFileUtilities #endif // COMMON_MAC_MACHO_WALKER_H__