1 //
2 // Copyright (C) 2015 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_GENERATOR_PAYLOAD_GENERATION_CONFIG_H_
18 #define UPDATE_ENGINE_PAYLOAD_GENERATOR_PAYLOAD_GENERATION_CONFIG_H_
19 
20 #include <cstddef>
21 
22 #include <memory>
23 #include <string>
24 #include <vector>
25 
26 #include <brillo/key_value_store.h>
27 
28 #include "update_engine/payload_consumer/payload_constants.h"
29 #include "update_engine/payload_generator/filesystem_interface.h"
30 #include "update_engine/update_metadata.pb.h"
31 
32 namespace chromeos_update_engine {
33 
34 struct PostInstallConfig {
35   // Whether the postinstall config is empty.
36   bool IsEmpty() const;
37 
38   // Whether this partition carries a filesystem with post-install program that
39   // must be run to finalize the update process.
40   bool run = false;
41 
42   // The path to the post-install program relative to the root of this
43   // filesystem.
44   std::string path;
45 
46   // The filesystem type used to mount the partition in order to run the
47   // post-install program.
48   std::string filesystem_type;
49 
50   // Whether this postinstall script should be ignored if it fails.
51   bool optional = false;
52 };
53 
54 struct PartitionConfig {
PartitionConfigPartitionConfig55   explicit PartitionConfig(std::string name) : name(name) {}
56 
57   // Returns whether the PartitionConfig is not an empty image and all the
58   // fields are set correctly to a valid image file.
59   bool ValidateExists() const;
60 
61   // Open then filesystem stored in this partition and stores it in
62   // |fs_interface|. Returns whether opening the filesystem worked.
63   bool OpenFilesystem();
64 
65   // The path to the partition file. This can be a regular file or a block
66   // device such as a loop device.
67   std::string path;
68 
69   // The path to the .map file associated with |path| if any. The .map file is
70   // generated by the Android filesystem generation tools when creating a
71   // filesystem and describes the blocks used by each file.
72   std::string mapfile_path;
73 
74   // The size of the data in |path|. If rootfs verification is used (verity)
75   // this value should match the size of the verity device for the rootfs, and
76   // the size of the whole kernel. This value could be smaller than the
77   // partition and is the size of the data update_engine assumes verified for
78   // the source image, and the size of that data it should generate for the
79   // target image.
80   uint64_t size = 0;
81 
82   // The FilesystemInterface implementation used to access this partition's
83   // files.
84   std::unique_ptr<FilesystemInterface> fs_interface;
85 
86   std::string name;
87 
88   PostInstallConfig postinstall;
89 };
90 
91 // The ImageConfig struct describes a pair of binaries kernel and rootfs and the
92 // metadata associated with the image they are part of, like build number, size,
93 // etc.
94 struct ImageConfig {
95   // Returns whether the ImageConfig is an empty image.
96   bool ValidateIsEmpty() const;
97 
98   // Load |rootfs_size| and |kernel.size| from the respective image files. For
99   // the kernel, the whole |kernel.path| file is assumed. For the rootfs, the
100   // size is detected from the filesystem.
101   // Returns whether the image size was properly detected.
102   bool LoadImageSize();
103 
104   // Load postinstall config from a key value store.
105   bool LoadPostInstallConfig(const brillo::KeyValueStore& store);
106 
107   // Returns whether the |image_info| field is empty.
108   bool ImageInfoIsEmpty() const;
109 
110   // The ImageInfo message defined in the update_metadata.proto file describes
111   // the metadata of the image.
112   ImageInfo image_info;
113 
114   // The updated partitions.
115   std::vector<PartitionConfig> partitions;
116 };
117 
118 struct PayloadVersion {
PayloadVersionPayloadVersion119   PayloadVersion() : PayloadVersion(0, 0) {}
120   PayloadVersion(uint64_t major_version, uint32_t minor_version);
121 
122   // Returns whether the PayloadVersion is valid.
123   bool Validate() const;
124 
125   // Return whether the passed |operation| is allowed by this payload.
126   bool OperationAllowed(InstallOperation_Type operation) const;
127 
128   // Whether this payload version is a delta payload.
129   bool IsDelta() const;
130 
131   // Tells whether the update is done in-place, that is, whether the operations
132   // read and write from the same partition.
133   bool InplaceUpdate() const;
134 
135   // The major version of the payload.
136   uint64_t major;
137 
138   // The minor version of the payload.
139   uint32_t minor;
140 
141   // Wheter the IMGDIFF operation is allowed based on the available compressor
142   // in the delta_generator and the one supported by the target.
143   bool imgdiff_allowed = false;
144 };
145 
146 // The PayloadGenerationConfig struct encapsulates all the configuration to
147 // build the requested payload. This includes information about the old and new
148 // image as well as the restrictions applied to the payload (like minor-version
149 // and full/delta payload).
150 struct PayloadGenerationConfig {
151   // Returns whether the PayloadGenerationConfig is valid.
152   bool Validate() const;
153 
154   // Image information about the new image that's the target of this payload.
155   ImageConfig target;
156 
157   // Image information pertaining the old image, if any. This is only valid
158   // if is_full is false, so we are requested a delta payload.
159   ImageConfig source;
160 
161   // Wheter the requested payload is a delta payload.
162   bool is_delta = false;
163 
164   // The major/minor version of the payload.
165   PayloadVersion version;
166 
167   // The size of the rootfs partition, that not necessarily is the same as the
168   // filesystem in either source or target version, since there is some space
169   // after the partition used to store the verity hashes and or the bootcache.
170   uint64_t rootfs_partition_size = 0;
171 
172   // The |hard_chunk_size| is the maximum size that a single operation should
173   // write in the destination. Operations bigger than chunk_size should be
174   // split. A value of -1 means no hard chunk size limit. A very low limit
175   // means more operations, and less of a chance to reuse the data.
176   ssize_t hard_chunk_size = -1;
177 
178   // The |soft_chunk_size| is the preferred chunk size to use when there's no
179   // significant impact to the operations. For example, REPLACE, MOVE and
180   // SOURCE_COPY operations are not significantly impacted by the chunk size,
181   // except for a few bytes overhead in the manifest to describe extra
182   // operations. On the other hand, splitting BSDIFF operations impacts the
183   // payload size since it is not possible to use the redundancy *between*
184   // chunks.
185   size_t soft_chunk_size = 2 * 1024 * 1024;
186 
187   // TODO(deymo): Remove the block_size member and maybe replace it with a
188   // minimum alignment size for blocks (if needed). Algorithms should be able to
189   // pick the block_size they want, but for now only 4 KiB is supported.
190 
191   // The block size used for all the operations in the manifest.
192   size_t block_size = 4096;
193 };
194 
195 }  // namespace chromeos_update_engine
196 
197 #endif  // UPDATE_ENGINE_PAYLOAD_GENERATOR_PAYLOAD_GENERATION_CONFIG_H_
198