diff options
Diffstat (limited to 'updater/blockimg.cpp')
| -rw-r--r-- | updater/blockimg.cpp | 141 |
1 files changed, 123 insertions, 18 deletions
diff --git a/updater/blockimg.cpp b/updater/blockimg.cpp index 2a2ab19a3..96b2d9feb 100644 --- a/updater/blockimg.cpp +++ b/updater/blockimg.cpp @@ -49,6 +49,7 @@ #include <fec/io.h> #include <openssl/sha.h> #include <private/android_filesystem_config.h> +#include <verity/hash_tree_builder.h> #include <ziparchive/zip_archive.h> #include "edify/expr.h" @@ -1495,6 +1496,105 @@ static int PerformCommandAbort(CommandParameters&) { return -1; } +// Computes the hash_tree bytes based on the parameters, checks if the root hash of the tree +// matches the expected hash and writes the result to the specified range on the block_device. +// Hash_tree computation arguments: +// hash_tree_ranges +// source_ranges +// hash_algorithm +// salt_hex +// root_hash +static int PerformCommandComputeHashTree(CommandParameters& params) { + if (params.cpos + 5 != params.tokens.size()) { + LOG(ERROR) << "Invaild arguments count in hash computation " << params.cmdline; + return -1; + } + + // Expects the hash_tree data to be contiguous. + RangeSet hash_tree_ranges = RangeSet::Parse(params.tokens[params.cpos++]); + if (!hash_tree_ranges || hash_tree_ranges.size() != 1) { + LOG(ERROR) << "Invalid hash tree ranges in " << params.cmdline; + return -1; + } + + RangeSet source_ranges = RangeSet::Parse(params.tokens[params.cpos++]); + if (!source_ranges) { + LOG(ERROR) << "Invalid source ranges in " << params.cmdline; + return -1; + } + + auto hash_function = HashTreeBuilder::HashFunction(params.tokens[params.cpos++]); + if (hash_function == nullptr) { + LOG(ERROR) << "Invalid hash algorithm in " << params.cmdline; + return -1; + } + + std::vector<unsigned char> salt; + std::string salt_hex = params.tokens[params.cpos++]; + if (salt_hex.empty() || !HashTreeBuilder::ParseBytesArrayFromString(salt_hex, &salt)) { + LOG(ERROR) << "Failed to parse salt in " << params.cmdline; + return -1; + } + + std::string expected_root_hash = params.tokens[params.cpos++]; + if (expected_root_hash.empty()) { + LOG(ERROR) << "Invalid root hash in " << params.cmdline; + return -1; + } + + // Starts the hash_tree computation. + HashTreeBuilder builder(BLOCKSIZE, hash_function); + if (!builder.Initialize(source_ranges.blocks() * BLOCKSIZE, salt)) { + LOG(ERROR) << "Failed to initialize hash tree computation, source " << source_ranges.ToString() + << ", salt " << salt_hex; + return -1; + } + + // Iterates through every block in the source_ranges and updates the hash tree structure + // accordingly. + for (const auto& range : source_ranges) { + uint8_t buffer[BLOCKSIZE]; + if (!check_lseek(params.fd, static_cast<off64_t>(range.first) * BLOCKSIZE, SEEK_SET)) { + PLOG(ERROR) << "Failed to seek to block: " << range.first; + return -1; + } + + for (size_t i = range.first; i < range.second; i++) { + if (read_all(params.fd, buffer, BLOCKSIZE) == -1) { + LOG(ERROR) << "Failed to read data in " << range.first << ":" << range.second; + return -1; + } + + if (!builder.Update(reinterpret_cast<unsigned char*>(buffer), BLOCKSIZE)) { + LOG(ERROR) << "Failed to update hash tree builder"; + return -1; + } + } + } + + if (!builder.BuildHashTree()) { + LOG(ERROR) << "Failed to build hash tree"; + return -1; + } + + std::string root_hash_hex = HashTreeBuilder::BytesArrayToString(builder.root_hash()); + if (root_hash_hex != expected_root_hash) { + LOG(ERROR) << "Root hash of the verity hash tree doesn't match the expected value. Expected: " + << expected_root_hash << ", actual: " << root_hash_hex; + return -1; + } + + uint64_t write_offset = static_cast<uint64_t>(hash_tree_ranges.GetBlockNumber(0)) * BLOCKSIZE; + if (params.canwrite && !builder.WriteHashTreeToFd(params.fd, write_offset)) { + LOG(ERROR) << "Failed to write hash tree to output"; + return -1; + } + + // TODO(xunchang) validates the written bytes + + return 0; +} + using CommandFunction = std::function<int(CommandParameters&)>; using CommandMap = std::unordered_map<Command::Type, CommandFunction>; @@ -1737,6 +1837,9 @@ static Value* PerformBlockImageUpdate(const char* name, State* state, if (performer(params) == -1) { LOG(ERROR) << "failed to execute command [" << line << "]"; + if (cmd_type == Command::Type::COMPUTE_HASH_TREE && failure_type == kNoCause) { + failure_type = kHashTreeComputationFailure; + } goto pbiudone; } @@ -1894,15 +1997,16 @@ Value* BlockImageVerifyFn(const char* name, State* state, // Commands which are not allowed are set to nullptr to skip them completely. const CommandMap command_map{ // clang-format off - { Command::Type::ABORT, PerformCommandAbort }, - { Command::Type::BSDIFF, PerformCommandDiff }, - { Command::Type::ERASE, nullptr }, - { Command::Type::FREE, PerformCommandFree }, - { Command::Type::IMGDIFF, PerformCommandDiff }, - { Command::Type::MOVE, PerformCommandMove }, - { Command::Type::NEW, nullptr }, - { Command::Type::STASH, PerformCommandStash }, - { Command::Type::ZERO, nullptr }, + { Command::Type::ABORT, PerformCommandAbort }, + { Command::Type::BSDIFF, PerformCommandDiff }, + { Command::Type::COMPUTE_HASH_TREE, PerformCommandComputeHashTree }, + { Command::Type::ERASE, nullptr }, + { Command::Type::FREE, PerformCommandFree }, + { Command::Type::IMGDIFF, PerformCommandDiff }, + { Command::Type::MOVE, PerformCommandMove }, + { Command::Type::NEW, nullptr }, + { Command::Type::STASH, PerformCommandStash }, + { Command::Type::ZERO, nullptr }, // clang-format on }; CHECK_EQ(static_cast<size_t>(Command::Type::LAST), command_map.size()); @@ -1915,15 +2019,16 @@ Value* BlockImageUpdateFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) { const CommandMap command_map{ // clang-format off - { Command::Type::ABORT, PerformCommandAbort }, - { Command::Type::BSDIFF, PerformCommandDiff }, - { Command::Type::ERASE, PerformCommandErase }, - { Command::Type::FREE, PerformCommandFree }, - { Command::Type::IMGDIFF, PerformCommandDiff }, - { Command::Type::MOVE, PerformCommandMove }, - { Command::Type::NEW, PerformCommandNew }, - { Command::Type::STASH, PerformCommandStash }, - { Command::Type::ZERO, PerformCommandZero }, + { Command::Type::ABORT, PerformCommandAbort }, + { Command::Type::BSDIFF, PerformCommandDiff }, + { Command::Type::COMPUTE_HASH_TREE, PerformCommandComputeHashTree }, + { Command::Type::ERASE, PerformCommandErase }, + { Command::Type::FREE, PerformCommandFree }, + { Command::Type::IMGDIFF, PerformCommandDiff }, + { Command::Type::MOVE, PerformCommandMove }, + { Command::Type::NEW, PerformCommandNew }, + { Command::Type::STASH, PerformCommandStash }, + { Command::Type::ZERO, PerformCommandZero }, // clang-format on }; CHECK_EQ(static_cast<size_t>(Command::Type::LAST), command_map.size()); |