| // | 
 | // Copyright (C) 2012 The Android Open Source Project | 
 | // | 
 | // Licensed under the Apache License, Version 2.0 (the "License"); | 
 | // you may not use this file except in compliance with the License. | 
 | // You may obtain a copy of the License at | 
 | // | 
 | //      http://www.apache.org/licenses/LICENSE-2.0 | 
 | // | 
 | // Unless required by applicable law or agreed to in writing, software | 
 | // distributed under the License is distributed on an "AS IS" BASIS, | 
 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | 
 | // See the License for the specific language governing permissions and | 
 | // limitations under the License. | 
 | // | 
 |  | 
 | #include "update_engine/payload_consumer/filesystem_verifier_action.h" | 
 |  | 
 | #include <errno.h> | 
 | #include <fcntl.h> | 
 | #include <sys/stat.h> | 
 | #include <sys/types.h> | 
 |  | 
 | #include <algorithm> | 
 | #include <cstdlib> | 
 | #include <string> | 
 |  | 
 | #include <base/bind.h> | 
 | #include <brillo/data_encoding.h> | 
 | #include <brillo/streams/file_stream.h> | 
 |  | 
 | #include "update_engine/common/boot_control_interface.h" | 
 | #include "update_engine/common/utils.h" | 
 | #include "update_engine/payload_consumer/delta_performer.h" | 
 | #include "update_engine/payload_consumer/payload_constants.h" | 
 |  | 
 | using brillo::data_encoding::Base64Encode; | 
 | using std::string; | 
 |  | 
 | namespace chromeos_update_engine { | 
 |  | 
 | namespace { | 
 | const off_t kReadFileBufferSize = 128 * 1024; | 
 | }  // namespace | 
 |  | 
 | void FilesystemVerifierAction::PerformAction() { | 
 |   // Will tell the ActionProcessor we've failed if we return. | 
 |   ScopedActionCompleter abort_action_completer(processor_, this); | 
 |  | 
 |   if (!HasInputObject()) { | 
 |     LOG(ERROR) << "FilesystemVerifierAction missing input object."; | 
 |     return; | 
 |   } | 
 |   install_plan_ = GetInputObject(); | 
 |  | 
 |   if (install_plan_.partitions.empty()) { | 
 |     LOG(INFO) << "No partitions to verify."; | 
 |     if (HasOutputPipe()) | 
 |       SetOutputObject(install_plan_); | 
 |     abort_action_completer.set_code(ErrorCode::kSuccess); | 
 |     return; | 
 |   } | 
 |  | 
 |   StartPartitionHashing(); | 
 |   abort_action_completer.set_should_complete(false); | 
 | } | 
 |  | 
 | void FilesystemVerifierAction::TerminateProcessing() { | 
 |   cancelled_ = true; | 
 |   Cleanup(ErrorCode::kSuccess);  // error code is ignored if canceled_ is true. | 
 | } | 
 |  | 
 | bool FilesystemVerifierAction::IsCleanupPending() const { | 
 |   return src_stream_ != nullptr; | 
 | } | 
 |  | 
 | void FilesystemVerifierAction::Cleanup(ErrorCode code) { | 
 |   src_stream_.reset(); | 
 |   // This memory is not used anymore. | 
 |   buffer_.clear(); | 
 |  | 
 |   if (cancelled_) | 
 |     return; | 
 |   if (code == ErrorCode::kSuccess && HasOutputPipe()) | 
 |     SetOutputObject(install_plan_); | 
 |   processor_->ActionComplete(this, code); | 
 | } | 
 |  | 
 | void FilesystemVerifierAction::StartPartitionHashing() { | 
 |   if (partition_index_ == install_plan_.partitions.size()) { | 
 |     Cleanup(ErrorCode::kSuccess); | 
 |     return; | 
 |   } | 
 |   InstallPlan::Partition& partition = | 
 |       install_plan_.partitions[partition_index_]; | 
 |  | 
 |   string part_path; | 
 |   switch (verifier_step_) { | 
 |     case VerifierStep::kVerifySourceHash: | 
 |       part_path = partition.source_path; | 
 |       remaining_size_ = partition.source_size; | 
 |       break; | 
 |     case VerifierStep::kVerifyTargetHash: | 
 |       part_path = partition.target_path; | 
 |       remaining_size_ = partition.target_size; | 
 |       break; | 
 |   } | 
 |   LOG(INFO) << "Hashing partition " << partition_index_ << " (" | 
 |             << partition.name << ") on device " << part_path; | 
 |   if (part_path.empty()) | 
 |     return Cleanup(ErrorCode::kFilesystemVerifierError); | 
 |  | 
 |   brillo::ErrorPtr error; | 
 |   src_stream_ = brillo::FileStream::Open( | 
 |       base::FilePath(part_path), | 
 |       brillo::Stream::AccessMode::READ, | 
 |       brillo::FileStream::Disposition::OPEN_EXISTING, | 
 |       &error); | 
 |  | 
 |   if (!src_stream_) { | 
 |     LOG(ERROR) << "Unable to open " << part_path << " for reading"; | 
 |     return Cleanup(ErrorCode::kFilesystemVerifierError); | 
 |   } | 
 |  | 
 |   buffer_.resize(kReadFileBufferSize); | 
 |   read_done_ = false; | 
 |   hasher_.reset(new HashCalculator()); | 
 |  | 
 |   // Start the first read. | 
 |   ScheduleRead(); | 
 | } | 
 |  | 
 | void FilesystemVerifierAction::ScheduleRead() { | 
 |   size_t bytes_to_read = std::min(static_cast<int64_t>(buffer_.size()), | 
 |                                   remaining_size_); | 
 |   if (!bytes_to_read) { | 
 |     OnReadDoneCallback(0); | 
 |     return; | 
 |   } | 
 |  | 
 |   bool read_async_ok = src_stream_->ReadAsync( | 
 |     buffer_.data(), | 
 |     bytes_to_read, | 
 |     base::Bind(&FilesystemVerifierAction::OnReadDoneCallback, | 
 |                base::Unretained(this)), | 
 |     base::Bind(&FilesystemVerifierAction::OnReadErrorCallback, | 
 |                base::Unretained(this)), | 
 |     nullptr); | 
 |  | 
 |   if (!read_async_ok) { | 
 |     LOG(ERROR) << "Unable to schedule an asynchronous read from the stream."; | 
 |     Cleanup(ErrorCode::kError); | 
 |   } | 
 | } | 
 |  | 
 | void FilesystemVerifierAction::OnReadDoneCallback(size_t bytes_read) { | 
 |   if (bytes_read == 0) { | 
 |     read_done_ = true; | 
 |   } else { | 
 |     remaining_size_ -= bytes_read; | 
 |     CHECK(!read_done_); | 
 |     if (!hasher_->Update(buffer_.data(), bytes_read)) { | 
 |       LOG(ERROR) << "Unable to update the hash."; | 
 |       Cleanup(ErrorCode::kError); | 
 |       return; | 
 |     } | 
 |   } | 
 |  | 
 |   // We either terminate the current partition or have more data to read. | 
 |   if (cancelled_) | 
 |     return Cleanup(ErrorCode::kError); | 
 |  | 
 |   if (read_done_ || remaining_size_ == 0) { | 
 |     if (remaining_size_ != 0) { | 
 |       LOG(ERROR) << "Failed to read the remaining " << remaining_size_ | 
 |                  << " bytes from partition " | 
 |                  << install_plan_.partitions[partition_index_].name; | 
 |       return Cleanup(ErrorCode::kFilesystemVerifierError); | 
 |     } | 
 |     return FinishPartitionHashing(); | 
 |   } | 
 |   ScheduleRead(); | 
 | } | 
 |  | 
 | void FilesystemVerifierAction::OnReadErrorCallback( | 
 |       const brillo::Error* error) { | 
 |   // TODO(deymo): Transform the read-error into an specific ErrorCode. | 
 |   LOG(ERROR) << "Asynchronous read failed."; | 
 |   Cleanup(ErrorCode::kError); | 
 | } | 
 |  | 
 | void FilesystemVerifierAction::FinishPartitionHashing() { | 
 |   if (!hasher_->Finalize()) { | 
 |     LOG(ERROR) << "Unable to finalize the hash."; | 
 |     return Cleanup(ErrorCode::kError); | 
 |   } | 
 |   InstallPlan::Partition& partition = | 
 |       install_plan_.partitions[partition_index_]; | 
 |   LOG(INFO) << "Hash of " << partition.name << ": " | 
 |             << Base64Encode(hasher_->raw_hash()); | 
 |  | 
 |   switch (verifier_step_) { | 
 |     case VerifierStep::kVerifyTargetHash: | 
 |       if (partition.target_hash != hasher_->raw_hash()) { | 
 |         LOG(ERROR) << "New '" << partition.name | 
 |                    << "' partition verification failed."; | 
 |         if (partition.source_hash.empty()) { | 
 |           // No need to verify source if it is a full payload. | 
 |           return Cleanup(ErrorCode::kNewRootfsVerificationError); | 
 |         } | 
 |         // If we have not verified source partition yet, now that the target | 
 |         // partition does not match, and it's not a full payload, we need to | 
 |         // switch to kVerifySourceHash step to check if it's because the source | 
 |         // partition does not match either. | 
 |         verifier_step_ = VerifierStep::kVerifySourceHash; | 
 |       } else { | 
 |         partition_index_++; | 
 |       } | 
 |       break; | 
 |     case VerifierStep::kVerifySourceHash: | 
 |       if (partition.source_hash != hasher_->raw_hash()) { | 
 |         LOG(ERROR) << "Old '" << partition.name | 
 |                    << "' partition verification failed."; | 
 |         LOG(ERROR) << "This is a server-side error due to mismatched delta" | 
 |                    << " update image!"; | 
 |         LOG(ERROR) << "The delta I've been given contains a " << partition.name | 
 |                    << " delta update that must be applied over a " | 
 |                    << partition.name << " with a specific checksum, but the " | 
 |                    << partition.name | 
 |                    << " we're starting with doesn't have that checksum! This" | 
 |                       " means that the delta I've been given doesn't match my" | 
 |                       " existing system. The " | 
 |                    << partition.name << " partition I have has hash: " | 
 |                    << Base64Encode(hasher_->raw_hash()) | 
 |                    << " but the update expected me to have " | 
 |                    << Base64Encode(partition.source_hash) << " ."; | 
 |         LOG(INFO) << "To get the checksum of the " << partition.name | 
 |                   << " partition run this command: dd if=" | 
 |                   << partition.source_path | 
 |                   << " bs=1M count=" << partition.source_size | 
 |                   << " iflag=count_bytes 2>/dev/null | openssl dgst -sha256 " | 
 |                      "-binary | openssl base64"; | 
 |         LOG(INFO) << "To get the checksum of partitions in a bin file, " | 
 |                   << "run: .../src/scripts/sha256_partitions.sh .../file.bin"; | 
 |         return Cleanup(ErrorCode::kDownloadStateInitializationError); | 
 |       } | 
 |       // The action will skip kVerifySourceHash step if target partition hash | 
 |       // matches, if we are in this step, it means target hash does not match, | 
 |       // and now that the source partition hash matches, we should set the error | 
 |       // code to reflect the error in target partition. | 
 |       // We only need to verify the source partition which the target hash does | 
 |       // not match, the rest of the partitions don't matter. | 
 |       return Cleanup(ErrorCode::kNewRootfsVerificationError); | 
 |   } | 
 |   // Start hashing the next partition, if any. | 
 |   hasher_.reset(); | 
 |   buffer_.clear(); | 
 |   src_stream_->CloseBlocking(nullptr); | 
 |   StartPartitionHashing(); | 
 | } | 
 |  | 
 | }  // namespace chromeos_update_engine |