1 //
2 // Copyright (C) 2018 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 #ifndef UPDATE_ENGINE_PAYLOAD_CONSUMER_VERITY_WRITER_ANDROID_H_
18 #define UPDATE_ENGINE_PAYLOAD_CONSUMER_VERITY_WRITER_ANDROID_H_
19 
20 #include <memory>
21 #include <string>
22 
23 #include <verity/hash_tree_builder.h>
24 
25 #include "update_engine/payload_consumer/verity_writer_interface.h"
26 
27 namespace chromeos_update_engine {
28 
29 class VerityWriterAndroid : public VerityWriterInterface {
30  public:
31   VerityWriterAndroid() = default;
32   ~VerityWriterAndroid() override = default;
33 
34   bool Init(const InstallPlan::Partition& partition) override;
35   bool Update(uint64_t offset, const uint8_t* buffer, size_t size) override;
36 
37   // Read [data_offset : data_offset + data_size) from |path| and encode FEC
38   // data, if |verify_mode|, then compare the encoded FEC with the one in
39   // |path|, otherwise write the encoded FEC to |path|. We can't encode as we go
40   // in each Update() like hash tree, because for every rs block, its data are
41   // spreaded across entire |data_size|, unless we can cache all data in
42   // memory, we have to re-read them from disk.
43   static bool EncodeFEC(const std::string& path,
44                         uint64_t data_offset,
45                         uint64_t data_size,
46                         uint64_t fec_offset,
47                         uint64_t fec_size,
48                         uint32_t fec_roots,
49                         uint32_t block_size,
50                         bool verify_mode);
51 
52  private:
53   const InstallPlan::Partition* partition_ = nullptr;
54 
55   std::unique_ptr<HashTreeBuilder> hash_tree_builder_;
56 
57   DISALLOW_COPY_AND_ASSIGN(VerityWriterAndroid);
58 };
59 
60 }  // namespace chromeos_update_engine
61 
62 #endif  // UPDATE_ENGINE_PAYLOAD_CONSUMER_VERITY_WRITER_ANDROID_H_
63