The Tor Browser: toolkit/crashreporter/google-breakpad/src/common/mac/macho

toolkit/crashreporter/google-breakpad/src/common/mac/macho_id.cc@b8a032363ba2 (annotated)

toolkit/crashreporter/google-breakpad/src/common/mac/macho_id.cc

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 // 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_id.cc: Functions to gather identifying information from a macho file
 //
 // See macho_id.h for documentation
 //
 // Author: Dan Waylonis
 extern "C" {  // necessary for Leopard
   #include <fcntl.h>
   #include <mach-o/loader.h>
   #include <mach-o/swap.h>
   #include <stdio.h>
   #include <stdlib.h>
   #include <string.h>
   #include <sys/time.h>
   #include <sys/types.h>
   #include <unistd.h>
 }
 #include "common/mac/macho_id.h"
 #include "common/mac/macho_walker.h"
 #include "common/mac/macho_utilities.h"
 namespace MacFileUtilities {
 using google_breakpad::MD5Init;
 using google_breakpad::MD5Update;
 using google_breakpad::MD5Final;
 MachoID::MachoID(const char *path)
    : memory_(0),
      memory_size_(0),
      crc_(0),
      md5_context_(),
      update_function_(NULL) {
   strlcpy(path_, path, sizeof(path_));
 }
 MachoID::MachoID(const char *path, void *memory, size_t size)
    : memory_(memory),
      memory_size_(size),
      crc_(0),
      md5_context_(),
      update_function_(NULL) {
   strlcpy(path_, path, sizeof(path_));
 }
 MachoID::~MachoID() {
 }
 // The CRC info is from http://en.wikipedia.org/wiki/Adler-32
 // With optimizations from http://www.zlib.net/
 // The largest prime smaller than 65536
 #define MOD_ADLER 65521
 // MAX_BLOCK is the largest n such that 255n(n+1)/2 + (n+1)(MAX_BLOCK-1) <= 2^32-1
 #define MAX_BLOCK 5552
 void MachoID::UpdateCRC(unsigned char *bytes, size_t size) {
 // Unrolled loops for summing
 #define DO1(buf,i)  {sum1 += (buf)[i]; sum2 += sum1;}
 #define DO2(buf,i)  DO1(buf,i); DO1(buf,i+1);
 #define DO4(buf,i)  DO2(buf,i); DO2(buf,i+2);
 #define DO8(buf,i)  DO4(buf,i); DO4(buf,i+4);
 #define DO16(buf)   DO8(buf,0); DO8(buf,8);
   // Split up the crc
   uint32_t sum1 = crc_ & 0xFFFF;
   uint32_t sum2 = (crc_ >> 16) & 0xFFFF;
   // Do large blocks
   while (size >= MAX_BLOCK) {
     size -= MAX_BLOCK;
     int block_count = MAX_BLOCK / 16;
     do {
       DO16(bytes);
       bytes += 16;
     } while (--block_count);
     sum1 %= MOD_ADLER;
     sum2 %= MOD_ADLER;
   }
   // Do remaining bytes
   if (size) {
     while (size >= 16) {
       size -= 16;
       DO16(bytes);
       bytes += 16;
     }
     while (size--) {
       sum1 += *bytes++;
       sum2 += sum1;
     }
     sum1 %= MOD_ADLER;
     sum2 %= MOD_ADLER;
     crc_ = (sum2 << 16) | sum1;
   }
 }
 void MachoID::UpdateMD5(unsigned char *bytes, size_t size) {
   MD5Update(&md5_context_, bytes, size);
 }
 void MachoID::Update(MachoWalker *walker, off_t offset, size_t size) {
   if (!update_function_ || !size)
     return;
   // Read up to 4k bytes at a time
   unsigned char buffer[4096];
   size_t buffer_size;
   off_t file_offset = offset;
   while (size > 0) {
     if (size > sizeof(buffer)) {
       buffer_size = sizeof(buffer);
       size -= buffer_size;
     } else {
       buffer_size = size;
       size = 0;
     }
     if (!walker->ReadBytes(buffer, buffer_size, file_offset))
       return;
     (this->*update_function_)(buffer, buffer_size);
     file_offset += buffer_size;
   }
 }
 bool MachoID::UUIDCommand(cpu_type_t cpu_type,
                           cpu_subtype_t cpu_subtype,
                           unsigned char bytes[16]) {
   struct breakpad_uuid_command uuid_cmd;
   uuid_cmd.cmd = 0;
   if (!WalkHeader(cpu_type, cpu_subtype, UUIDWalkerCB, &uuid_cmd))
     return false;
   // If we found the command, we'll have initialized the uuid_command
   // structure
   if (uuid_cmd.cmd == LC_UUID) {
     memcpy(bytes, uuid_cmd.uuid, sizeof(uuid_cmd.uuid));
     return true;
   }
   return false;
 }
 bool MachoID::IDCommand(cpu_type_t cpu_type,
                         cpu_subtype_t cpu_subtype,
                         unsigned char identifier[16]) {
   struct dylib_command dylib_cmd;
   dylib_cmd.cmd = 0;
   if (!WalkHeader(cpu_type, cpu_subtype, IDWalkerCB, &dylib_cmd))
     return false;
   // If we found the command, we'll have initialized the dylib_command
   // structure
   if (dylib_cmd.cmd == LC_ID_DYLIB) {
     // Take the hashed filename, version, and compatability version bytes
     // to form the first 12 bytes, pad the rest with zeros
     // create a crude hash of the filename to generate the first 4 bytes
     identifier[0] = 0;
     identifier[1] = 0;
     identifier[2] = 0;
     identifier[3] = 0;
     for (int j = 0, i = (int)strlen(path_)-1; i>=0 && path_[i]!='/'; ++j, --i) {
       identifier[j%4] += path_[i];
     }
     identifier[4] = (dylib_cmd.dylib.current_version >> 24) & 0xFF;
     identifier[5] = (dylib_cmd.dylib.current_version >> 16) & 0xFF;
     identifier[6] = (dylib_cmd.dylib.current_version >> 8) & 0xFF;
     identifier[7] = dylib_cmd.dylib.current_version & 0xFF;
     identifier[8] = (dylib_cmd.dylib.compatibility_version >> 24) & 0xFF;
     identifier[9] = (dylib_cmd.dylib.compatibility_version >> 16) & 0xFF;
     identifier[10] = (dylib_cmd.dylib.compatibility_version >> 8) & 0xFF;
     identifier[11] = dylib_cmd.dylib.compatibility_version & 0xFF;
     identifier[12] = (cpu_type >> 24) & 0xFF;
     identifier[13] = (cpu_type >> 16) & 0xFF;
     identifier[14] = (cpu_type >> 8) & 0xFF;
     identifier[15] = cpu_type & 0xFF;
     return true;
   }
   return false;
 }
 uint32_t MachoID::Adler32(cpu_type_t cpu_type, cpu_subtype_t cpu_subtype) {
   update_function_ = &MachoID::UpdateCRC;
   crc_ = 0;
   if (!WalkHeader(cpu_type, cpu_subtype, WalkerCB, this))
     return 0;
   return crc_;
 }
 bool MachoID::MD5(cpu_type_t cpu_type, cpu_subtype_t cpu_subtype, unsigned char identifier[16]) {
   update_function_ = &MachoID::UpdateMD5;
   MD5Init(&md5_context_);
   if (!WalkHeader(cpu_type, cpu_subtype, WalkerCB, this))
     return false;
   MD5Final(identifier, &md5_context_);
   return true;
 }
 bool MachoID::WalkHeader(cpu_type_t cpu_type,
                          cpu_subtype_t cpu_subtype,
                          MachoWalker::LoadCommandCallback callback,
                          void *context) {
   if (memory_) {
     MachoWalker walker(memory_, memory_size_, callback, context);
     return walker.WalkHeader(cpu_type, cpu_subtype);
   } else {
     MachoWalker walker(path_, callback, context);
     return walker.WalkHeader(cpu_type, cpu_subtype);
   }
 }
 // static
 bool MachoID::WalkerCB(MachoWalker *walker, load_command *cmd, off_t offset,
                        bool swap, void *context) {
   MachoID *macho_id = (MachoID *)context;
   if (cmd->cmd == LC_SEGMENT) {
     struct segment_command seg;
     if (!walker->ReadBytes(&seg, sizeof(seg), offset))
       return false;
     if (swap)
       swap_segment_command(&seg, NXHostByteOrder());
     struct mach_header_64 header;
     off_t header_offset;
     if (!walker->CurrentHeader(&header, &header_offset))
       return false;
     // Process segments that have sections:
     // (e.g., __TEXT, __DATA, __IMPORT, __OBJC)
     offset += sizeof(struct segment_command);
     struct section sec;
     for (unsigned long i = 0; i < seg.nsects; ++i) {
       if (!walker->ReadBytes(&sec, sizeof(sec), offset))
         return false;
       if (swap)
         swap_section(&sec, 1, NXHostByteOrder());
       // sections of type S_ZEROFILL are "virtual" and contain no data
       // in the file itself
       if ((sec.flags & SECTION_TYPE) != S_ZEROFILL && sec.offset != 0)
         macho_id->Update(walker, header_offset + sec.offset, sec.size);
       offset += sizeof(struct section);
     }
   } else if (cmd->cmd == LC_SEGMENT_64) {
     struct segment_command_64 seg64;
     if (!walker->ReadBytes(&seg64, sizeof(seg64), offset))
       return false;
     if (swap)
       breakpad_swap_segment_command_64(&seg64, NXHostByteOrder());
     struct mach_header_64 header;
     off_t header_offset;
     if (!walker->CurrentHeader(&header, &header_offset))
       return false;
     // Process segments that have sections:
     // (e.g., __TEXT, __DATA, __IMPORT, __OBJC)
     offset += sizeof(struct segment_command_64);
     struct section_64 sec64;
     for (unsigned long i = 0; i < seg64.nsects; ++i) {
       if (!walker->ReadBytes(&sec64, sizeof(sec64), offset))
         return false;
       if (swap)
         breakpad_swap_section_64(&sec64, 1, NXHostByteOrder());
       // sections of type S_ZEROFILL are "virtual" and contain no data
       // in the file itself
       if ((sec64.flags & SECTION_TYPE) != S_ZEROFILL && sec64.offset != 0)
         macho_id->Update(walker,
                          header_offset + sec64.offset,
                          (size_t)sec64.size);
       offset += sizeof(struct section_64);
     }
   }
   // Continue processing
   return true;
 }
 // static
 bool MachoID::UUIDWalkerCB(MachoWalker *walker, load_command *cmd, off_t offset,
                            bool swap, void *context) {
   if (cmd->cmd == LC_UUID) {
     struct breakpad_uuid_command *uuid_cmd =
       (struct breakpad_uuid_command *)context;
     if (!walker->ReadBytes(uuid_cmd, sizeof(struct breakpad_uuid_command),
                            offset))
       return false;
     if (swap)
       breakpad_swap_uuid_command(uuid_cmd, NXHostByteOrder());
     return false;
   }
   // Continue processing
   return true;
 }
 // static
 bool MachoID::IDWalkerCB(MachoWalker *walker, load_command *cmd, off_t offset,
                          bool swap, void *context) {
   if (cmd->cmd == LC_ID_DYLIB) {
     struct dylib_command *dylib_cmd = (struct dylib_command *)context;
     if (!walker->ReadBytes(dylib_cmd, sizeof(struct dylib_command), offset))
       return false;
     if (swap)
       swap_dylib_command(dylib_cmd, NXHostByteOrder());
     return false;
   }
   // Continue processing
   return true;
 }
 }  // namespace MacFileUtilities

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toolkit/crashreporter/google-breakpad/src/common/mac/macho_id.cc@b8a032363ba2 (annotated)

toolkit/crashreporter/google-breakpad/src/common/mac/macho_id.cc