1 //
2 // Copyright (C) 2021 The Android Open Source Project
3 //
4 // Licensed under the Apache License, Version 2.0 (the "License");
5 // you may not use this file except in compliance with the License.
6 // You may obtain a copy of the License at
7 //
8 //      http://www.apache.org/licenses/LICENSE-2.0
9 //
10 // Unless required by applicable law or agreed to in writing, software
11 // distributed under the License is distributed on an "AS IS" BASIS,
12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 // See the License for the specific language governing permissions and
14 // limitations under the License.
15 //
16 
17 #include <algorithm>
18 #include <memory>
19 
20 #include <unistd.h>
21 
22 #include <android-base/file.h>
23 #include <gtest/gtest.h>
24 #include <libsnapshot/mock_cow_writer.h>
25 
26 #include "update_engine/common/utils.h"
27 #include "update_engine/payload_consumer/extent_map.h"
28 #include "update_engine/payload_consumer/file_descriptor.h"
29 #include "update_engine/payload_consumer/xor_extent_writer.h"
30 #include "update_engine/payload_generator/delta_diff_generator.h"
31 #include "update_engine/payload_generator/extent_ranges.h"
32 #include "update_engine/payload_generator/merge_sequence_generator.h"
33 #include "update_engine/update_metadata.pb.h"
34 
35 namespace chromeos_update_engine {
36 
37 using testing::_;
38 using testing::Args;
39 using testing::Return;
40 
41 class XorExtentWriterTest : public ::testing::Test {
42  public:
43   static constexpr size_t NUM_BLOCKS = 50;
SetUp()44   void SetUp() override {
45     ASSERT_EQ(ftruncate64(source_part_.fd, kBlockSize * NUM_BLOCKS), 0);
46     ASSERT_EQ(ftruncate64(target_part_.fd, kBlockSize * NUM_BLOCKS), 0);
47 
48     // Fill source part with arbitrary data, as we are computing XOR between
49     // source and target data later.
50     ASSERT_EQ(lseek(source_part_.fd, 0, SEEK_SET), 0);
51     brillo::Blob buffer(kBlockSize);
52     for (size_t i = 0; i < kBlockSize; i++) {
53       buffer[i] = i & 0xFF;
54     }
55     for (size_t i = 0; i < NUM_BLOCKS; i++) {
56       ASSERT_EQ(write(source_part_.fd, buffer.data(), buffer.size()),
57                 static_cast<ssize_t>(buffer.size()));
58     }
59     ASSERT_EQ(fsync(source_part_.fd), 0);
60     ASSERT_EQ(fsync(target_part_.fd), 0);
61     ASSERT_TRUE(source_fd_->Open(source_part_.path, O_RDONLY | O_CREAT, 0644));
62   }
63   InstallOperation op_;
64   FileDescriptorPtr source_fd_ = std::make_shared<EintrSafeFileDescriptor>();
65   ExtentMap<const CowMergeOperation*> xor_map_;
66   android::snapshot::MockCowWriter cow_writer_;
67   TemporaryFile source_part_;
68   TemporaryFile target_part_;
69 };
70 
71 MATCHER_P2(BytesEqual,
72            bytes,
73            size,
74            "Check if args match expected value byte for byte") {
75   return std::get<1>(arg) == size && std::get<0>(arg) != nullptr &&
76          memcmp(std::get<0>(arg), bytes, size) == 0;
77 }
78 
TEST_F(XorExtentWriterTest,StreamTest)79 TEST_F(XorExtentWriterTest, StreamTest) {
80   constexpr auto COW_XOR = CowMergeOperation::COW_XOR;
81   ON_CALL(cow_writer_, AddXorBlocks(_, _, _, _, _)).WillByDefault(Return(true));
82   const auto op1 = CreateCowMergeOperation(
83       ExtentForRange(5, 2), ExtentForRange(5, 2), COW_XOR);
84   ASSERT_TRUE(xor_map_.AddExtent(op1.dst_extent(), &op1));
85   *op_.add_src_extents() = op1.src_extent();
86   *op_.add_dst_extents() = op1.dst_extent();
87 
88   const auto op2 = CreateCowMergeOperation(
89       ExtentForRange(45, 2), ExtentForRange(456, 2), COW_XOR);
90   ASSERT_TRUE(xor_map_.AddExtent(op2.dst_extent(), &op2));
91   *op_.add_src_extents() = ExtentForRange(45, 3);
92   *op_.add_dst_extents() = ExtentForRange(455, 3);
93 
94   const auto op3 = CreateCowMergeOperation(
95       ExtentForRange(12, 2), ExtentForRange(321, 2), COW_XOR, 777);
96   ASSERT_TRUE(xor_map_.AddExtent(op3.dst_extent(), &op3));
97   *op_.add_src_extents() = ExtentForRange(12, 4);
98   *op_.add_dst_extents() = ExtentForRange(320, 4);
99   XORExtentWriter writer_{
100       op_, source_fd_, &cow_writer_, xor_map_, NUM_BLOCKS * kBlockSize};
101 
102   // OTA op:
103   // [5-6] => [5-6], [45-47] => [455-457], [12-15] => [320-323]
104 
105   // merge op:
106   // [5-6] => [5-6], [45-46] => [456-457], [12-13] => [321-322]
107 
108   // Expected result:
109   // [5-7], [45-47], [12-14] should be XOR blocks
110   // [320], [323], [455] should be regular replace blocks
111 
112   auto zeros = utils::GetReadonlyZeroBlock(kBlockSize * 10);
113   EXPECT_CALL(cow_writer_,
114               AddRawBlocks(455, zeros->data() + 2 * kBlockSize, kBlockSize))
115       .With(Args<1, 2>(BytesEqual(zeros->data(), kBlockSize)))
116       .WillOnce(Return(true));
117   EXPECT_CALL(cow_writer_,
118               AddRawBlocks(320, zeros->data() + 5 * kBlockSize, kBlockSize))
119       .With(Args<1, 2>(BytesEqual(zeros->data(), kBlockSize)))
120       .WillOnce(Return(true));
121   EXPECT_CALL(cow_writer_,
122               AddRawBlocks(323, zeros->data() + 8 * kBlockSize, kBlockSize))
123       .With(Args<1, 2>(BytesEqual(zeros->data(), kBlockSize)))
124       .WillOnce(Return(true));
125 
126   EXPECT_CALL(cow_writer_, AddXorBlocks(5, _, kBlockSize * 2, 5, 0))
127       .WillOnce(Return(true));
128   EXPECT_CALL(cow_writer_, AddXorBlocks(456, _, kBlockSize * 2, 45, 0))
129       .WillOnce(Return(true));
130   EXPECT_CALL(cow_writer_, AddXorBlocks(321, _, kBlockSize * 2, 12, 777))
131       .WillOnce(Return(true));
132 
133   ASSERT_TRUE(writer_.Init(op_.dst_extents(), kBlockSize));
134   ASSERT_TRUE(writer_.Write(zeros->data(), 9 * kBlockSize));
135 }
136 
TEST_F(XorExtentWriterTest,SubsetExtentTest)137 TEST_F(XorExtentWriterTest, SubsetExtentTest) {
138   constexpr auto COW_XOR = CowMergeOperation::COW_XOR;
139   ON_CALL(cow_writer_, AddXorBlocks(_, _, _, _, _)).WillByDefault(Return(true));
140 
141   const auto op3 = CreateCowMergeOperation(
142       ExtentForRange(12, 4), ExtentForRange(320, 4), COW_XOR, 777);
143   ASSERT_TRUE(xor_map_.AddExtent(op3.dst_extent(), &op3));
144 
145   *op_.add_src_extents() = ExtentForRange(12, 3);
146   *op_.add_dst_extents() = ExtentForRange(320, 3);
147   *op_.add_src_extents() = ExtentForRange(20, 3);
148   *op_.add_dst_extents() = ExtentForRange(420, 3);
149   *op_.add_src_extents() = ExtentForRange(15, 1);
150   *op_.add_dst_extents() = ExtentForRange(323, 1);
151   XORExtentWriter writer_{
152       op_, source_fd_, &cow_writer_, xor_map_, NUM_BLOCKS * kBlockSize};
153 
154   // OTA op:
155   // [12-14] => [320-322], [20-22] => [420-422], [15-16] => [323-324]
156 
157   // merge op:
158   // [12-16] => [321-322]
159 
160   // Expected result:
161   // [12-16] should be XOR blocks
162   // [420-422] should be regular replace blocks
163 
164   auto zeros = utils::GetReadonlyZeroBlock(kBlockSize * 7);
165   EXPECT_CALL(cow_writer_,
166               AddRawBlocks(420, zeros->data() + 3 * kBlockSize, kBlockSize * 3))
167       .WillOnce(Return(true));
168 
169   EXPECT_CALL(cow_writer_, AddXorBlocks(320, _, kBlockSize * 3, 12, 777))
170       .WillOnce(Return(true));
171   EXPECT_CALL(cow_writer_, AddXorBlocks(323, _, kBlockSize, 15, 777))
172       .WillOnce(Return(true));
173 
174   ASSERT_TRUE(writer_.Init(op_.dst_extents(), kBlockSize));
175   ASSERT_TRUE(writer_.Write(zeros->data(), zeros->size()));
176 }
177 
TEST_F(XorExtentWriterTest,LastBlockTest)178 TEST_F(XorExtentWriterTest, LastBlockTest) {
179   constexpr auto COW_XOR = CowMergeOperation::COW_XOR;
180   ON_CALL(cow_writer_, AddXorBlocks(_, _, _, _, _)).WillByDefault(Return(true));
181 
182   const auto op3 = CreateCowMergeOperation(
183       ExtentForRange(NUM_BLOCKS - 1, 1), ExtentForRange(2, 1), COW_XOR, 777);
184   ASSERT_TRUE(xor_map_.AddExtent(op3.dst_extent(), &op3));
185 
186   *op_.add_src_extents() = ExtentForRange(12, 3);
187   *op_.add_dst_extents() = ExtentForRange(320, 3);
188 
189   *op_.add_src_extents() = ExtentForRange(20, 3);
190   *op_.add_dst_extents() = ExtentForRange(420, 3);
191 
192   *op_.add_src_extents() = ExtentForRange(NUM_BLOCKS - 3, 3);
193   *op_.add_dst_extents() = ExtentForRange(2, 3);
194   XORExtentWriter writer_{
195       op_, source_fd_, &cow_writer_, xor_map_, NUM_BLOCKS * kBlockSize};
196 
197   // OTA op:
198   // [12-14] => [320-322], [20-22] => [420-422], [NUM_BLOCKS-3] => [2-5]
199 
200   // merge op:
201   // [NUM_BLOCKS-1] => [2]
202 
203   // Expected result:
204   // [320-322] should be REPLACE blocks
205   // [420-422] should be REPLACE blocks
206   // [2] should be XOR blocks, with 0 offset to avoid out of bound read
207   // [3-5] should be REPLACE BLOCKS
208 
209   auto zeros = utils::GetReadonlyZeroBlock(kBlockSize * 9);
210   EXPECT_CALL(cow_writer_, AddRawBlocks(320, zeros->data(), kBlockSize * 3))
211       .WillOnce(Return(true));
212   EXPECT_CALL(cow_writer_,
213               AddRawBlocks(420, zeros->data() + 3 * kBlockSize, kBlockSize * 3))
214       .WillOnce(Return(true));
215 
216   EXPECT_CALL(cow_writer_, AddXorBlocks(2, _, kBlockSize, NUM_BLOCKS - 1, 0))
217       .WillOnce(Return(true));
218   EXPECT_CALL(cow_writer_,
219               AddRawBlocks(3, zeros->data() + kBlockSize * 7, kBlockSize * 2))
220       .WillOnce(Return(true));
221 
222   ASSERT_TRUE(writer_.Init(op_.dst_extents(), kBlockSize));
223   ASSERT_TRUE(writer_.Write(zeros->data(), zeros->size()));
224 }
225 
TEST_F(XorExtentWriterTest,LastMultiBlockTest)226 TEST_F(XorExtentWriterTest, LastMultiBlockTest) {
227   constexpr auto COW_XOR = CowMergeOperation::COW_XOR;
228 
229   const auto op3 = CreateCowMergeOperation(
230       ExtentForRange(NUM_BLOCKS - 4, 4), ExtentForRange(2, 4), COW_XOR, 777);
231   ASSERT_TRUE(xor_map_.AddExtent(op3.dst_extent(), &op3));
232 
233   *op_.add_src_extents() = ExtentForRange(NUM_BLOCKS - 4, 4);
234   *op_.add_dst_extents() = ExtentForRange(2, 4);
235   XORExtentWriter writer_{
236       op_, source_fd_, &cow_writer_, xor_map_, NUM_BLOCKS * kBlockSize};
237 
238   // OTA op:
239   // [NUM_BLOCKS-4] => [2-5]
240 
241   // merge op:
242   // [NUM_BLOCKS-4] => [2-5]
243 
244   // Expected result:
245   // [12-16] should be REPLACE blocks
246   // [420-422] should be REPLACE blocks
247   // [2-3] should be XOR blocks
248   // [4] should be XOR blocks with 0 offset to avoid out of bound read
249 
250   // Send arbitrary data, just to confirm that XORExtentWriter did XOR the
251   // source data with target data
252   std::vector<uint8_t> op_data(kBlockSize * 4);
253   for (size_t i = 0; i < op_data.size(); i++) {
254     if (i % kBlockSize == 0) {
255       op_data[i] = 1;
256     } else {
257       op_data[i] = (op_data[i - 1] * 3) & 0xFF;
258     }
259   }
260   auto&& verify_xor_data = [source_fd_(source_fd_), &op_data](
261                                uint32_t new_block_start,
262                                const void* data,
263                                size_t size,
264                                uint32_t old_block,
265                                uint16_t offset) -> bool {
266     std::vector<uint8_t> source_data(size);
267     ssize_t bytes_read{};
268     TEST_AND_RETURN_FALSE_ERRNO(utils::PReadAll(source_fd_,
269                                                 source_data.data(),
270                                                 source_data.size(),
271                                                 old_block * kBlockSize + offset,
272                                                 &bytes_read));
273     TEST_EQ(bytes_read, static_cast<ssize_t>(source_data.size()));
274     std::transform(source_data.begin(),
275                    source_data.end(),
276                    static_cast<const uint8_t*>(data),
277                    source_data.begin(),
278                    std::bit_xor<uint8_t>{});
279     if (memcmp(source_data.data(), op_data.data(), source_data.size()) != 0) {
280       LOG(ERROR) << "XOR data received does not appear to be an XOR between "
281                     "source and target data";
282       return false;
283     }
284     return true;
285   };
286   EXPECT_CALL(cow_writer_,
287               AddXorBlocks(2, _, kBlockSize * 3, NUM_BLOCKS - 4, 777))
288       .WillOnce(verify_xor_data);
289   EXPECT_CALL(cow_writer_, AddXorBlocks(5, _, kBlockSize, NUM_BLOCKS - 1, 0))
290       .WillOnce(verify_xor_data);
291 
292   ASSERT_TRUE(writer_.Init(op_.dst_extents(), kBlockSize));
293   ASSERT_TRUE(writer_.Write(op_data.data(), op_data.size()));
294 }
295 
296 }  // namespace chromeos_update_engine
297