Home | History | Annotate | Download | only in fs_mgr 
      1 /*
      2  * Copyright (C) 2016 The Android Open Source Project
      3  *
      4  * Permission is hereby granted, free of charge, to any person
      5  * obtaining a copy of this software and associated documentation
      6  * files (the "Software"), to deal in the Software without
      7  * restriction, including without limitation the rights to use, copy,
      8  * modify, merge, publish, distribute, sublicense, and/or sell copies
      9  * of the Software, and to permit persons to whom the Software is
     10  * furnished to do so, subject to the following conditions:
     11  *
     12  * The above copyright notice and this permission notice shall be
     13  * included in all copies or substantial portions of the Software.
     14  *
     15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
     16  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
     17  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
     18  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
     19  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
     20  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
     21  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
     22  * SOFTWARE.
     23  */
     24 
     25 #ifndef __CORE_FS_MGR_PRIV_AVB_OPS_H
     26 #define __CORE_FS_MGR_PRIV_AVB_OPS_H
     27 
     28 #include <map>
     29 #include <string>
     30 
     31 #include <libavb/libavb.h>
     32 
     33 #include "fs_mgr.h"
     34 
     35 // This class provides C++ bindings to interact with libavb, a small
     36 // self-contained piece of code that's intended to be used in bootloaders.
     37 // It mainly contains two functions:
     38 //   - ReadFromPartition(): to read AVB metadata from a given partition.
     39 //     It provides the implementation of AvbOps.read_from_partition() when
     40 //     reading metadata through libavb.
     41 //   - AvbSlotVerify(): the C++ binding of libavb->avb_slot_verify() to
     42 //     read and verify the metadata and store it into the out_data parameter.
     43 //     The caller MUST check the integrity of metadata against the
     44 //     androidboot.vbmeta.{hash_alg, size, digest} values from /proc/cmdline.
     45 //     e.g., see class FsManagerAvbVerifier for more details.
     46 //
     47 class FsManagerAvbOps {
     48   public:
     49     FsManagerAvbOps(const fstab& fstab);
     50     FsManagerAvbOps(std::map<std::string, std::string>&& by_name_symlink_map);
     51 
     52     static FsManagerAvbOps* GetInstanceFromAvbOps(AvbOps* ops) {
     53         return reinterpret_cast<FsManagerAvbOps*>(ops->user_data);
     54     }
     55 
     56     AvbIOResult ReadFromPartition(const char* partition, int64_t offset, size_t num_bytes,
     57                                   void* buffer, size_t* out_num_read);
     58 
     59     AvbSlotVerifyResult AvbSlotVerify(const std::string& ab_suffix, AvbSlotVerifyFlags flags,
     60                                       AvbSlotVerifyData** out_data);
     61 
     62   private:
     63     void InitializeAvbOps();
     64 
     65     AvbOps avb_ops_;
     66     std::map<std::string, std::string> by_name_symlink_map_;
     67 };
     68 #endif /* __CORE_FS_MGR_PRIV_AVB_OPS_H */
     69