1    :  // Copyright 2013 Google Inc. All Rights Reserved.
   2    :  //
   3    :  // Licensed under the Apache License, Version 2.0 (the "License");
   4    :  // you may not use this file except in compliance with the License.
   5    :  // You may obtain a copy of the License at
   6    :  //
   7    :  //     http://www.apache.org/licenses/LICENSE-2.0
   8    :  //
   9    :  // Unless required by applicable law or agreed to in writing, software
  10    :  // distributed under the License is distributed on an "AS IS" BASIS,
  11    :  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12    :  // See the License for the specific language governing permissions and
  13    :  // limitations under the License.
  14    :  
  15    :  #include "syzygy/instrument/instrumenters/branch_instrumenter.h"
  16    :  
  17    :  #include "base/logging.h"
  18    :  #include "base/files/file_util.h"
  19    :  #include "base/strings/string_number_conversions.h"
  20    :  #include "syzygy/application/application.h"
  21    :  #include "syzygy/pe/image_filter.h"
  22    :  
  23    :  namespace instrument {
  24    :  namespace instrumenters {
  25    :  
  26    :  const char BranchInstrumenter::kAgentDllBasicBlockEntry[] =
  27    :      "basic_block_entry_client.dll";
  28    :  const uint32 kNumSlots = 4U;
  29    :  
  30    :  BranchInstrumenter::BranchInstrumenter()
  31  E :      : buffering_(false), fs_slot_(0U) {
  32  E :    agent_dll_ = kAgentDllBasicBlockEntry;
  33  E :  }
  34    :  
  35  E :  bool BranchInstrumenter::InstrumentPrepare() {
  36  E :    return true;
  37  E :  }
  38    :  
  39  E :  bool BranchInstrumenter::InstrumentImpl() {
  40    :    branch_transform_.reset(
  41  E :        new instrument::transforms::BranchHookTransform());
  42  E :    branch_transform_->set_instrument_dll_name(agent_dll_);
  43  E :    branch_transform_->set_buffering(buffering_);
  44  E :    branch_transform_->set_fs_slot(fs_slot_);
  45  E :    if (!relinker_->AppendTransform(branch_transform_.get()))
  46  i :      return false;
  47    :  
  48    :    add_bb_addr_stream_mutator_.reset(new
  49    :        instrument::mutators::AddIndexedDataRangesStreamPdbMutator(
  50    :            branch_transform_->bb_ranges(),
  51  E :            common::kBasicBlockRangesStreamName));
  52  E :    if (!relinker_->AppendPdbMutator(add_bb_addr_stream_mutator_.get()))
  53  i :      return false;
  54    :  
  55  E :    return true;
  56  E :  }
  57    :  
  58    :  bool BranchInstrumenter::DoCommandLineParse(
  59  E :      const base::CommandLine* command_line) {
  60  E :    if (!Super::DoCommandLineParse(command_line))
  61  i :      return false;
  62    :  
  63    :    // Parse the additional command line arguments.
  64  E :    buffering_ = command_line->HasSwitch("buffering");
  65    :  
  66  E :    if (command_line->HasSwitch("fs-slot")) {
  67  E :      std::string fs_slot_str = command_line->GetSwitchValueASCII("fs-slot");
  68  E :      if (!base::StringToUint(fs_slot_str, &fs_slot_)) {
  69  E :        LOG(ERROR) << "Unrecognized FS-slot: not a valid number.";
  70  E :        return false;
  71    :      }
  72  E :      if (fs_slot_ == 0 || fs_slot_ > kNumSlots) {
  73  E :        LOG(ERROR) << "fs-slot must be from 1 to " << kNumSlots << ".";
  74  E :        return false;
  75    :      }
  76  E :    }
  77  E :    return true;
  78  E :  }
  79    :  
  80    :  }  // namespace instrumenters
  81    :  }  // namespace instrument