1    :  // Copyright 2015 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/refinery/analyzers/exception_analyzer.h"
  16    :  
  17    :  #include <dbghelp.h>
  18    :  #include <memory>
  19    :  
  20    :  #include "syzygy/refinery/analyzers/analyzer_util.h"
  21    :  #include "syzygy/refinery/process_state/process_state_util.h"
  22    :  #include "syzygy/refinery/process_state/refinery.pb.h"
  23    :  
  24  m :  namespace refinery {
  25    :  
  26    :  // static
  27  m :  const char ExceptionAnalyzer::kExceptionAnalyzerName[] = "ExceptionAnalyzer";
  28    :  
  29  m :  Analyzer::AnalysisResult ExceptionAnalyzer::Analyze(
  30  m :      const minidump::Minidump& minidump,
  31  m :      const ProcessAnalysis& process_analysis) {
  32  m :    DCHECK(process_analysis.process_state() != nullptr);
  33    :  
  34    :    // Retrieve the unique exception stream.
  35  m :    minidump::Minidump::Stream exception_stream =
  36  m :        minidump.FindNextStream(nullptr, ExceptionStream);
  37  m :    if (!exception_stream.IsValid()) {
  38    :      // Minidump has no exception data.
  39  m :      return ANALYSIS_COMPLETE;
  40  m :    }
  41  m :    minidump::Minidump::Stream offending_stream =
  42  m :        minidump.FindNextStream(&exception_stream, ExceptionStream);
  43  m :    if (offending_stream.IsValid())
  44  m :      return ANALYSIS_ERROR;
  45    :  
  46  m :    MINIDUMP_EXCEPTION_STREAM minidump_exception_stream = {};
  47  m :    if (!exception_stream.ReadAndAdvanceElement(&minidump_exception_stream))
  48  m :      return ANALYSIS_ERROR;
  49  m :    const MINIDUMP_EXCEPTION& exception_record =
  50  m :        minidump_exception_stream.ExceptionRecord;
  51    :  
  52    :    // TODO(manzagop): Consider chained exceptions
  53    :    // (exception_record.ExceptionRecord).
  54    :  
  55    :    // Populate the exception information.
  56  m :    Exception exception;
  57  m :    exception.set_thread_id(minidump_exception_stream.ThreadId);
  58  m :    exception.set_exception_code(exception_record.ExceptionCode);
  59  m :    exception.set_exception_flags(exception_record.ExceptionFlags);
  60  m :    exception.set_exception_record(exception_record.ExceptionRecord);
  61  m :    exception.set_exception_address(exception_record.ExceptionAddress);
  62  m :    for (int i = 0; i < exception_record.NumberParameters; ++i) {
  63  m :      exception.add_exception_information(
  64  m :          exception_record.ExceptionInformation[i]);
  65  m :    }
  66    :  
  67  m :    minidump::Minidump::Stream thread_context =
  68  m :        minidump.GetStreamFor(minidump_exception_stream.ThreadContext);
  69  m :    if (!thread_context.IsValid())
  70  m :      return ANALYSIS_ERROR;
  71    :    // TODO(siggi): This ought to probe for the architecture somehow.
  72  m :    CONTEXT ctx = {};
  73  m :    if (!thread_context.ReadAndAdvanceElement(&ctx))
  74  m :      return ANALYSIS_ERROR;
  75  m :    ParseContext(ctx, exception.mutable_register_info());
  76    :  
  77    :    // Add the exception information to the process state.
  78  m :    if (!process_analysis.process_state()->SetException(exception))
  79  m :      return ANALYSIS_ERROR;
  80    :  
  81  m :    return ANALYSIS_COMPLETE;
  82  m :  }
  83    :  
  84  m :  }  // namespace refinery