1    :  // Copyright 2014 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/agent/asan/block_utils.h"
  16    :  
  17    :  #include "gtest/gtest.h"
  18    :  #include "syzygy/agent/asan/asan_logger.h"
  19    :  #include "syzygy/agent/asan/unittest_util.h"
  20    :  
  21    :  namespace agent {
  22    :  namespace asan {
  23    :  
  24    :  namespace {
  25    :  
  26    :  typedef testing::TestWithAsanRuntime BlockUtilTest;
  27    :  
  28    :  }  // namespace
  29    :  
  30  E :  TEST_F(BlockUtilTest, IsBlockCorruptInvalidMagicNumber) {
  31  E :    const size_t kAllocSize = 100;
  32  E :    testing::FakeAsanBlock fake_block(kShadowRatioLog, runtime_->stack_cache());
  33  E :    EXPECT_TRUE(fake_block.InitializeBlock(kAllocSize));
  34    :  
  35  E :    fake_block.block_info.header->magic = ~kBlockHeaderMagic;
  36  E :    EXPECT_TRUE(IsBlockCorrupt(fake_block.block_info.block, NULL));
  37  E :    fake_block.block_info.header->magic = kBlockHeaderMagic;
  38  E :    EXPECT_FALSE(IsBlockCorrupt(fake_block.block_info.block, NULL));
  39  E :  }
  40    :  
  41  E :  TEST_F(BlockUtilTest, IsBlockCorruptInvalidChecksum) {
  42  E :    const size_t kAllocSize = 100;
  43    :    static const size_t kChecksumRepeatCount = 10;
  44    :  
  45    :    // This can fail because of a checksum collision. However, we run it a
  46    :    // handful of times to keep the chances as small as possible.
  47  E :    for (size_t i = 0; i < kChecksumRepeatCount; ++i) {
  48  E :      testing::FakeAsanBlock fake_block(kShadowRatioLog, runtime_->stack_cache());
  49  E :      EXPECT_TRUE(fake_block.InitializeBlock(kAllocSize));
  50  E :      EXPECT_TRUE(fake_block.MarkBlockAsQuarantined());
  51    :  
  52    :      // Change some of the block content and verify that the block is now being
  53    :      // seen as corrupt.
  54  E :      size_t original_checksum = fake_block.block_info.header->checksum;
  55  E :      uint8 original_value = fake_block.block_info.body[0];
  56  E :      fake_block.block_info.body[0]++;
  57    :  
  58    :      // Try again for all but the last attempt if this appears to have failed.
  59    :      if (!IsBlockCorrupt(fake_block.block_info.body, NULL) &&
  60  E :          i + 1 < kChecksumRepeatCount) {
  61  i :        continue;
  62    :      }
  63    :  
  64  E :      ASSERT_TRUE(IsBlockCorrupt(fake_block.block_info.body, NULL));
  65  E :      fake_block.block_info.body[0] = original_value;
  66  E :      ASSERT_FALSE(IsBlockCorrupt(fake_block.block_info.body, NULL));
  67  E :      break;
  68  i :    }
  69  E :  }
  70    :  
  71    :  }  // namespace asan
  72    :  }  // namespace agent