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//
// 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/delta_performer.h"
#include <endian.h>
#include <errno.h>
#include <linux/fs.h>
#include <algorithm>
#include <cstring>
#include <memory>
#include <string>
#include <vector>
#include <base/files/file_util.h>
#include <base/format_macros.h>
#include <base/memory/ptr_util.h>
#include <base/metrics/histogram_macros.h>
#include <base/strings/string_number_conversions.h>
#include <base/strings/string_util.h>
#include <base/strings/stringprintf.h>
#include <base/time/time.h>
#include <brillo/data_encoding.h>
#include <bsdiff/bspatch.h>
#include <google/protobuf/repeated_field.h>
#include "update_engine/common/constants.h"
#include "update_engine/common/hardware_interface.h"
#include "update_engine/common/prefs_interface.h"
#include "update_engine/common/subprocess.h"
#include "update_engine/common/terminator.h"
#include "update_engine/payload_consumer/bzip_extent_writer.h"
#include "update_engine/payload_consumer/download_action.h"
#include "update_engine/payload_consumer/extent_writer.h"
#if USE_MTD
#include "update_engine/payload_consumer/mtd_file_descriptor.h"
#endif
#include "update_engine/payload_consumer/payload_constants.h"
#include "update_engine/payload_consumer/payload_verifier.h"
#include "update_engine/payload_consumer/xz_extent_writer.h"
using google::protobuf::RepeatedPtrField;
using std::min;
using std::string;
using std::vector;
namespace chromeos_update_engine {
const uint64_t DeltaPerformer::kDeltaVersionOffset = sizeof(kDeltaMagic);
const uint64_t DeltaPerformer::kDeltaVersionSize = 8;
const uint64_t DeltaPerformer::kDeltaManifestSizeOffset =
kDeltaVersionOffset + kDeltaVersionSize;
const uint64_t DeltaPerformer::kDeltaManifestSizeSize = 8;
const uint64_t DeltaPerformer::kDeltaMetadataSignatureSizeSize = 4;
const uint64_t DeltaPerformer::kMaxPayloadHeaderSize = 24;
const uint64_t DeltaPerformer::kSupportedMajorPayloadVersion = 2;
const uint32_t DeltaPerformer::kSupportedMinorPayloadVersion = 3;
const unsigned DeltaPerformer::kProgressLogMaxChunks = 10;
const unsigned DeltaPerformer::kProgressLogTimeoutSeconds = 30;
const unsigned DeltaPerformer::kProgressDownloadWeight = 50;
const unsigned DeltaPerformer::kProgressOperationsWeight = 50;
namespace {
const int kUpdateStateOperationInvalid = -1;
const int kMaxResumedUpdateFailures = 10;
#if USE_MTD
const int kUbiVolumeAttachTimeout = 5 * 60;
#endif
FileDescriptorPtr CreateFileDescriptor(const char* path) {
FileDescriptorPtr ret;
#if USE_MTD
if (strstr(path, "/dev/ubi") == path) {
if (!UbiFileDescriptor::IsUbi(path)) {
// The volume might not have been attached at boot time.
int volume_no;
if (utils::SplitPartitionName(path, nullptr, &volume_no)) {
utils::TryAttachingUbiVolume(volume_no, kUbiVolumeAttachTimeout);
}
}
if (UbiFileDescriptor::IsUbi(path)) {
LOG(INFO) << path << " is a UBI device.";
ret.reset(new UbiFileDescriptor);
}
} else if (MtdFileDescriptor::IsMtd(path)) {
LOG(INFO) << path << " is an MTD device.";
ret.reset(new MtdFileDescriptor);
} else {
LOG(INFO) << path << " is not an MTD nor a UBI device.";
#endif
ret.reset(new EintrSafeFileDescriptor);
#if USE_MTD
}
#endif
return ret;
}
// Opens path for read/write. On success returns an open FileDescriptor
// and sets *err to 0. On failure, sets *err to errno and returns nullptr.
FileDescriptorPtr OpenFile(const char* path, int mode, int* err) {
// Try to mark the block device read-only based on the mode. Ignore any
// failure since this won't work when passing regular files.
utils::SetBlockDeviceReadOnly(path, (mode & O_ACCMODE) == O_RDONLY);
FileDescriptorPtr fd = CreateFileDescriptor(path);
#if USE_MTD
// On NAND devices, we can either read, or write, but not both. So here we
// use O_WRONLY.
if (UbiFileDescriptor::IsUbi(path) || MtdFileDescriptor::IsMtd(path)) {
mode = O_WRONLY;
}
#endif
if (!fd->Open(path, mode, 000)) {
*err = errno;
PLOG(ERROR) << "Unable to open file " << path;
return nullptr;
}
*err = 0;
return fd;
}
// Discard the tail of the block device referenced by |fd|, from the offset
// |data_size| until the end of the block device. Returns whether the data was
// discarded.
bool DiscardPartitionTail(const FileDescriptorPtr& fd, uint64_t data_size) {
uint64_t part_size = fd->BlockDevSize();
if (!part_size || part_size <= data_size)
return false;
struct blkioctl_request {
int number;
const char* name;
};
const vector<blkioctl_request> blkioctl_requests = {
{BLKDISCARD, "BLKDISCARD"},
{BLKSECDISCARD, "BLKSECDISCARD"},
#ifdef BLKZEROOUT
{BLKZEROOUT, "BLKZEROOUT"},
#endif
};
for (const auto& req : blkioctl_requests) {
int error = 0;
if (fd->BlkIoctl(req.number, data_size, part_size - data_size, &error) &&
error == 0) {
return true;
}
LOG(WARNING) << "Error discarding the last "
<< (part_size - data_size) / 1024 << " KiB using ioctl("
<< req.name << ")";
}
return false;
}
} // namespace
// Computes the ratio of |part| and |total|, scaled to |norm|, using integer
// arithmetic.
static uint64_t IntRatio(uint64_t part, uint64_t total, uint64_t norm) {
return part * norm / total;
}
void DeltaPerformer::LogProgress(const char* message_prefix) {
// Format operations total count and percentage.
string total_operations_str("?");
string completed_percentage_str("");
if (num_total_operations_) {
total_operations_str = std::to_string(num_total_operations_);
// Upcasting to 64-bit to avoid overflow, back to size_t for formatting.
completed_percentage_str =
base::StringPrintf(" (%" PRIu64 "%%)",
IntRatio(next_operation_num_, num_total_operations_,
100));
}
// Format download total count and percentage.
size_t payload_size = install_plan_->payload_size;
string payload_size_str("?");
string downloaded_percentage_str("");
if (payload_size) {
payload_size_str = std::to_string(payload_size);
// Upcasting to 64-bit to avoid overflow, back to size_t for formatting.
downloaded_percentage_str =
base::StringPrintf(" (%" PRIu64 "%%)",
IntRatio(total_bytes_received_, payload_size, 100));
}
LOG(INFO) << (message_prefix ? message_prefix : "") << next_operation_num_
<< "/" << total_operations_str << " operations"
<< completed_percentage_str << ", " << total_bytes_received_
<< "/" << payload_size_str << " bytes downloaded"
<< downloaded_percentage_str << ", overall progress "
<< overall_progress_ << "%";
}
void DeltaPerformer::UpdateOverallProgress(bool force_log,
const char* message_prefix) {
// Compute our download and overall progress.
unsigned new_overall_progress = 0;
static_assert(kProgressDownloadWeight + kProgressOperationsWeight == 100,
"Progress weights don't add up");
// Only consider download progress if its total size is known; otherwise
// adjust the operations weight to compensate for the absence of download
// progress. Also, make sure to cap the download portion at
// kProgressDownloadWeight, in case we end up downloading more than we
// initially expected (this indicates a problem, but could generally happen).
// TODO(garnold) the correction of operations weight when we do not have the
// total payload size, as well as the conditional guard below, should both be
// eliminated once we ensure that the payload_size in the install plan is
// always given and is non-zero. This currently isn't the case during unit
// tests (see chromium-os:37969).
size_t payload_size = install_plan_->payload_size;
unsigned actual_operations_weight = kProgressOperationsWeight;
if (payload_size)
new_overall_progress += min(
static_cast<unsigned>(IntRatio(total_bytes_received_, payload_size,
kProgressDownloadWeight)),
kProgressDownloadWeight);
else
actual_operations_weight += kProgressDownloadWeight;
// Only add completed operations if their total number is known; we definitely
// expect an update to have at least one operation, so the expectation is that
// this will eventually reach |actual_operations_weight|.
if (num_total_operations_)
new_overall_progress += IntRatio(next_operation_num_, num_total_operations_,
actual_operations_weight);
// Progress ratio cannot recede, unless our assumptions about the total
// payload size, total number of operations, or the monotonicity of progress
// is breached.
if (new_overall_progress < overall_progress_) {
LOG(WARNING) << "progress counter receded from " << overall_progress_
<< "% down to " << new_overall_progress << "%; this is a bug";
force_log = true;
}
overall_progress_ = new_overall_progress;
// Update chunk index, log as needed: if forced by called, or we completed a
// progress chunk, or a timeout has expired.
base::Time curr_time = base::Time::Now();
unsigned curr_progress_chunk =
overall_progress_ * kProgressLogMaxChunks / 100;
if (force_log || curr_progress_chunk > last_progress_chunk_ ||
curr_time > forced_progress_log_time_) {
forced_progress_log_time_ = curr_time + forced_progress_log_wait_;
LogProgress(message_prefix);
}
last_progress_chunk_ = curr_progress_chunk;
}
size_t DeltaPerformer::CopyDataToBuffer(const char** bytes_p, size_t* count_p,
size_t max) {
const size_t count = *count_p;
if (!count)
return 0; // Special case shortcut.
size_t read_len = min(count, max - buffer_.size());
const char* bytes_start = *bytes_p;
const char* bytes_end = bytes_start + read_len;
buffer_.insert(buffer_.end(), bytes_start, bytes_end);
*bytes_p = bytes_end;
*count_p = count - read_len;
return read_len;
}
bool DeltaPerformer::HandleOpResult(bool op_result, const char* op_type_name,
ErrorCode* error) {
if (op_result)
return true;
size_t partition_first_op_num =
current_partition_ ? acc_num_operations_[current_partition_ - 1] : 0;
LOG(ERROR) << "Failed to perform " << op_type_name << " operation "
<< next_operation_num_ << ", which is the operation "
<< next_operation_num_ - partition_first_op_num
<< " in partition \""
<< partitions_[current_partition_].partition_name() << "\"";
if (*error == ErrorCode::kSuccess)
*error = ErrorCode::kDownloadOperationExecutionError;
return false;
}
int DeltaPerformer::Close() {
int err = -CloseCurrentPartition();
LOG_IF(ERROR, !payload_hash_calculator_.Finalize() ||
!signed_hash_calculator_.Finalize())
<< "Unable to finalize the hash.";
if (!buffer_.empty()) {
LOG(INFO) << "Discarding " << buffer_.size() << " unused downloaded bytes";
if (err >= 0)
err = 1;
}
return -err;
}
int DeltaPerformer::CloseCurrentPartition() {
int err = 0;
if (source_fd_ && !source_fd_->Close()) {
err = errno;
PLOG(ERROR) << "Error closing source partition";
if (!err)
err = 1;
}
source_fd_.reset();
source_path_.clear();
if (target_fd_ && !target_fd_->Close()) {
err = errno;
PLOG(ERROR) << "Error closing target partition";
if (!err)
err = 1;
}
target_fd_.reset();
target_path_.clear();
return -err;
}
bool DeltaPerformer::OpenCurrentPartition() {
if (current_partition_ >= partitions_.size())
return false;
const PartitionUpdate& partition = partitions_[current_partition_];
// Open source fds if we have a delta payload with minor version >= 2.
if (install_plan_->payload_type == InstallPayloadType::kDelta &&
GetMinorVersion() != kInPlaceMinorPayloadVersion) {
source_path_ = install_plan_->partitions[current_partition_].source_path;
int err;
source_fd_ = OpenFile(source_path_.c_str(), O_RDONLY, &err);
if (!source_fd_) {
LOG(ERROR) << "Unable to open source partition "
<< partition.partition_name() << " on slot "
<< BootControlInterface::SlotName(install_plan_->source_slot)
<< ", file " << source_path_;
return false;
}
}
target_path_ = install_plan_->partitions[current_partition_].target_path;
int err;
target_fd_ = OpenFile(target_path_.c_str(), O_RDWR | O_DSYNC, &err);
if (!target_fd_) {
LOG(ERROR) << "Unable to open target partition "
<< partition.partition_name() << " on slot "
<< BootControlInterface::SlotName(install_plan_->target_slot)
<< ", file " << target_path_;
return false;
}
LOG(INFO) << "Applying " << partition.operations().size()
<< " operations to partition \"" << partition.partition_name()
<< "\"";
// Discard the end of the partition, but ignore failures.
DiscardPartitionTail(
target_fd_, install_plan_->partitions[current_partition_].target_size);
return true;
}
namespace {
void LogPartitionInfoHash(const PartitionInfo& info, const string& tag) {
string sha256 = brillo::data_encoding::Base64Encode(info.hash());
LOG(INFO) << "PartitionInfo " << tag << " sha256: " << sha256
<< " size: " << info.size();
}
void LogPartitionInfo(const vector<PartitionUpdate>& partitions) {
for (const PartitionUpdate& partition : partitions) {
LogPartitionInfoHash(partition.old_partition_info(),
"old " + partition.partition_name());
LogPartitionInfoHash(partition.new_partition_info(),
"new " + partition.partition_name());
}
}
} // namespace
bool DeltaPerformer::GetMetadataSignatureSizeOffset(
uint64_t* out_offset) const {
if (GetMajorVersion() == kBrilloMajorPayloadVersion) {
*out_offset = kDeltaManifestSizeOffset + kDeltaManifestSizeSize;
return true;
}
return false;
}
bool DeltaPerformer::GetManifestOffset(uint64_t* out_offset) const {
// Actual manifest begins right after the manifest size field or
// metadata signature size field if major version >= 2.
if (major_payload_version_ == kChromeOSMajorPayloadVersion) {
*out_offset = kDeltaManifestSizeOffset + kDeltaManifestSizeSize;
return true;
}
if (major_payload_version_ == kBrilloMajorPayloadVersion) {
*out_offset = kDeltaManifestSizeOffset + kDeltaManifestSizeSize +
kDeltaMetadataSignatureSizeSize;
return true;
}
LOG(ERROR) << "Unknown major payload version: " << major_payload_version_;
return false;
}
uint64_t DeltaPerformer::GetMetadataSize() const {
return metadata_size_;
}
uint64_t DeltaPerformer::GetMajorVersion() const {
return major_payload_version_;
}
uint32_t DeltaPerformer::GetMinorVersion() const {
if (manifest_.has_minor_version()) {
return manifest_.minor_version();
} else {
return install_plan_->payload_type == InstallPayloadType::kDelta
? kSupportedMinorPayloadVersion
: kFullPayloadMinorVersion;
}
}
bool DeltaPerformer::GetManifest(DeltaArchiveManifest* out_manifest_p) const {
if (!manifest_parsed_)
return false;
*out_manifest_p = manifest_;
return true;
}
bool DeltaPerformer::IsHeaderParsed() const {
return metadata_size_ != 0;
}
DeltaPerformer::MetadataParseResult DeltaPerformer::ParsePayloadMetadata(
const brillo::Blob& payload, ErrorCode* error) {
*error = ErrorCode::kSuccess;
uint64_t manifest_offset;
if (!IsHeaderParsed()) {
// Ensure we have data to cover the major payload version.
if (payload.size() < kDeltaManifestSizeOffset)
return kMetadataParseInsufficientData;
// Validate the magic string.
if (memcmp(payload.data(), kDeltaMagic, sizeof(kDeltaMagic)) != 0) {
LOG(ERROR) << "Bad payload format -- invalid delta magic.";
*error = ErrorCode::kDownloadInvalidMetadataMagicString;
return kMetadataParseError;
}
// Extract the payload version from the metadata.
static_assert(sizeof(major_payload_version_) == kDeltaVersionSize,
"Major payload version size mismatch");
memcpy(&major_payload_version_,
&payload[kDeltaVersionOffset],
kDeltaVersionSize);
// switch big endian to host
major_payload_version_ = be64toh(major_payload_version_);
if (major_payload_version_ != supported_major_version_ &&
major_payload_version_ != kChromeOSMajorPayloadVersion) {
LOG(ERROR) << "Bad payload format -- unsupported payload version: "
<< major_payload_version_;
*error = ErrorCode::kUnsupportedMajorPayloadVersion;
return kMetadataParseError;
}
// Get the manifest offset now that we have payload version.
if (!GetManifestOffset(&manifest_offset)) {
*error = ErrorCode::kUnsupportedMajorPayloadVersion;
return kMetadataParseError;
}
// Check again with the manifest offset.
if (payload.size() < manifest_offset)
return kMetadataParseInsufficientData;
// Next, parse the manifest size.
static_assert(sizeof(manifest_size_) == kDeltaManifestSizeSize,
"manifest_size size mismatch");
memcpy(&manifest_size_,
&payload[kDeltaManifestSizeOffset],
kDeltaManifestSizeSize);
manifest_size_ = be64toh(manifest_size_); // switch big endian to host
if (GetMajorVersion() == kBrilloMajorPayloadVersion) {
// Parse the metadata signature size.
static_assert(sizeof(metadata_signature_size_) ==
kDeltaMetadataSignatureSizeSize,
"metadata_signature_size size mismatch");
uint64_t metadata_signature_size_offset;
if (!GetMetadataSignatureSizeOffset(&metadata_signature_size_offset)) {
*error = ErrorCode::kError;
return kMetadataParseError;
}
memcpy(&metadata_signature_size_,
&payload[metadata_signature_size_offset],
kDeltaMetadataSignatureSizeSize);
metadata_signature_size_ = be32toh(metadata_signature_size_);
}
// If the metadata size is present in install plan, check for it immediately
// even before waiting for that many number of bytes to be downloaded in the
// payload. This will prevent any attack which relies on us downloading data
// beyond the expected metadata size.
metadata_size_ = manifest_offset + manifest_size_;
if (install_plan_->hash_checks_mandatory) {
if (install_plan_->metadata_size != metadata_size_) {
LOG(ERROR) << "Mandatory metadata size in Omaha response ("
<< install_plan_->metadata_size
<< ") is missing/incorrect, actual = " << metadata_size_;
*error = ErrorCode::kDownloadInvalidMetadataSize;
return kMetadataParseError;
}
}
}
// Now that we have validated the metadata size, we should wait for the full
// metadata and its signature (if exist) to be read in before we can parse it.
if (payload.size() < metadata_size_ + metadata_signature_size_)
return kMetadataParseInsufficientData;
// Log whether we validated the size or simply trusting what's in the payload
// here. This is logged here (after we received the full metadata data) so
// that we just log once (instead of logging n times) if it takes n
// DeltaPerformer::Write calls to download the full manifest.
if (install_plan_->metadata_size == metadata_size_) {
LOG(INFO) << "Manifest size in payload matches expected value from Omaha";
} else {
// For mandatory-cases, we'd have already returned a kMetadataParseError
// above. We'll be here only for non-mandatory cases. Just send a UMA stat.
LOG(WARNING) << "Ignoring missing/incorrect metadata size ("
<< install_plan_->metadata_size
<< ") in Omaha response as validation is not mandatory. "
<< "Trusting metadata size in payload = " << metadata_size_;
}
// We have the full metadata in |payload|. Verify its integrity
// and authenticity based on the information we have in Omaha response.
*error = ValidateMetadataSignature(payload);
if (*error != ErrorCode::kSuccess) {
if (install_plan_->hash_checks_mandatory) {
// The autoupdate_CatchBadSignatures test checks for this string
// in log-files. Keep in sync.
LOG(ERROR) << "Mandatory metadata signature validation failed";
return kMetadataParseError;
}
// For non-mandatory cases, just send a UMA stat.
LOG(WARNING) << "Ignoring metadata signature validation failures";
*error = ErrorCode::kSuccess;
}
if (!GetManifestOffset(&manifest_offset)) {
*error = ErrorCode::kUnsupportedMajorPayloadVersion;
return kMetadataParseError;
}
// The payload metadata is deemed valid, it's safe to parse the protobuf.
if (!manifest_.ParseFromArray(&payload[manifest_offset], manifest_size_)) {
LOG(ERROR) << "Unable to parse manifest in update file.";
*error = ErrorCode::kDownloadManifestParseError;
return kMetadataParseError;
}
manifest_parsed_ = true;
return kMetadataParseSuccess;
}
#define OP_DURATION_HISTOGRAM(_op_name, _start_time) \
LOCAL_HISTOGRAM_CUSTOM_TIMES( \
"UpdateEngine.DownloadAction.InstallOperation::" \
_op_name ".Duration", \
base::TimeTicks::Now() - _start_time, \
base::TimeDelta::FromMilliseconds(10), \
base::TimeDelta::FromMinutes(5), \
20);
// Wrapper around write. Returns true if all requested bytes
// were written, or false on any error, regardless of progress
// and stores an action exit code in |error|.
bool DeltaPerformer::Write(const void* bytes, size_t count, ErrorCode *error) {
*error = ErrorCode::kSuccess;
const char* c_bytes = reinterpret_cast<const char*>(bytes);
// Update the total byte downloaded count and the progress logs.
total_bytes_received_ += count;
UpdateOverallProgress(false, "Completed ");
while (!manifest_valid_) {
// Read data up to the needed limit; this is either maximium payload header
// size, or the full metadata size (once it becomes known).
const bool do_read_header = !IsHeaderParsed();
CopyDataToBuffer(&c_bytes, &count,
(do_read_header ? kMaxPayloadHeaderSize :
metadata_size_ + metadata_signature_size_));
MetadataParseResult result = ParsePayloadMetadata(buffer_, error);
if (result == kMetadataParseError)
return false;
if (result == kMetadataParseInsufficientData) {
// If we just processed the header, make an attempt on the manifest.
if (do_read_header && IsHeaderParsed())
continue;
return true;
}
// Checks the integrity of the payload manifest.
if ((*error = ValidateManifest()) != ErrorCode::kSuccess)
return false;
manifest_valid_ = true;
// Clear the download buffer.
DiscardBuffer(false, metadata_size_);
// This populates |partitions_| and the |install_plan.partitions| with the
// list of partitions from the manifest.
if (!ParseManifestPartitions(error))
return false;
num_total_operations_ = 0;
for (const auto& partition : partitions_) {
num_total_operations_ += partition.operations_size();
acc_num_operations_.push_back(num_total_operations_);
}
LOG_IF(WARNING, !prefs_->SetInt64(kPrefsManifestMetadataSize,
metadata_size_))
<< "Unable to save the manifest metadata size.";
LOG_IF(WARNING, !prefs_->SetInt64(kPrefsManifestSignatureSize,
metadata_signature_size_))
<< "Unable to save the manifest signature size.";
if (!PrimeUpdateState()) {
*error = ErrorCode::kDownloadStateInitializationError;
LOG(ERROR) << "Unable to prime the update state.";
return false;
}
if (!OpenCurrentPartition()) {
*error = ErrorCode::kInstallDeviceOpenError;
return false;
}
if (next_operation_num_ > 0)
UpdateOverallProgress(true, "Resuming after ");
LOG(INFO) << "Starting to apply update payload operations";
}
while (next_operation_num_ < num_total_operations_) {
// Check if we should cancel the current attempt for any reason.
// In this case, *error will have already been populated with the reason
// why we're canceling.
if (download_delegate_ && download_delegate_->ShouldCancel(error))
return false;
// We know there are more operations to perform because we didn't reach the
// |num_total_operations_| limit yet.
while (next_operation_num_ >= acc_num_operations_[current_partition_]) {
CloseCurrentPartition();
current_partition_++;
if (!OpenCurrentPartition()) {
*error = ErrorCode::kInstallDeviceOpenError;
return false;
}
}
const size_t partition_operation_num = next_operation_num_ - (
current_partition_ ? acc_num_operations_[current_partition_ - 1] : 0);
const InstallOperation& op =
partitions_[current_partition_].operations(partition_operation_num);
CopyDataToBuffer(&c_bytes, &count, op.data_length());
// Check whether we received all of the next operation's data payload.
if (!CanPerformInstallOperation(op))
return true;
// Validate the operation only if the metadata signature is present.
// Otherwise, keep the old behavior. This serves as a knob to disable
// the validation logic in case we find some regression after rollout.
// NOTE: If hash checks are mandatory and if metadata_signature is empty,
// we would have already failed in ParsePayloadMetadata method and thus not
// even be here. So no need to handle that case again here.
if (!install_plan_->metadata_signature.empty()) {
// Note: Validate must be called only if CanPerformInstallOperation is
// called. Otherwise, we might be failing operations before even if there
// isn't sufficient data to compute the proper hash.
*error = ValidateOperationHash(op);
if (*error != ErrorCode::kSuccess) {
if (install_plan_->hash_checks_mandatory) {
LOG(ERROR) << "Mandatory operation hash check failed";
return false;
}
// For non-mandatory cases, just send a UMA stat.
LOG(WARNING) << "Ignoring operation validation errors";
*error = ErrorCode::kSuccess;
}
}
// Makes sure we unblock exit when this operation completes.
ScopedTerminatorExitUnblocker exit_unblocker =
ScopedTerminatorExitUnblocker(); // Avoids a compiler unused var bug.
base::TimeTicks op_start_time = base::TimeTicks::Now();
bool op_result;
switch (op.type()) {
case InstallOperation::REPLACE:
case InstallOperation::REPLACE_BZ:
case InstallOperation::REPLACE_XZ:
op_result = PerformReplaceOperation(op);
OP_DURATION_HISTOGRAM("REPLACE", op_start_time);
break;
case InstallOperation::ZERO:
case InstallOperation::DISCARD:
op_result = PerformZeroOrDiscardOperation(op);
OP_DURATION_HISTOGRAM("ZERO_OR_DISCARD", op_start_time);
break;
case InstallOperation::MOVE:
op_result = PerformMoveOperation(op);
OP_DURATION_HISTOGRAM("MOVE", op_start_time);
break;
case InstallOperation::BSDIFF:
op_result = PerformBsdiffOperation(op);
OP_DURATION_HISTOGRAM("BSDIFF", op_start_time);
break;
case InstallOperation::SOURCE_COPY:
op_result = PerformSourceCopyOperation(op, error);
OP_DURATION_HISTOGRAM("SOURCE_COPY", op_start_time);
break;
case InstallOperation::SOURCE_BSDIFF:
op_result = PerformSourceBsdiffOperation(op, error);
OP_DURATION_HISTOGRAM("SOURCE_BSDIFF", op_start_time);
break;
case InstallOperation::IMGDIFF:
// TODO(deymo): Replace with PUFFIN operation.
op_result = false;
break;
default:
op_result = false;
}
if (!HandleOpResult(op_result, InstallOperationTypeName(op.type()), error))
return false;
next_operation_num_++;
UpdateOverallProgress(false, "Completed ");
CheckpointUpdateProgress();
}
// In major version 2, we don't add dummy operation to the payload.
// If we already extracted the signature we should skip this step.
if (major_payload_version_ == kBrilloMajorPayloadVersion &&
manifest_.has_signatures_offset() && manifest_.has_signatures_size() &&
signatures_message_data_.empty()) {
if (manifest_.signatures_offset() != buffer_offset_) {
LOG(ERROR) << "Payload signatures offset points to blob offset "
<< manifest_.signatures_offset()
<< " but signatures are expected at offset "
<< buffer_offset_;
*error = ErrorCode::kDownloadPayloadVerificationError;
return false;
}
CopyDataToBuffer(&c_bytes, &count, manifest_.signatures_size());
// Needs more data to cover entire signature.
if (buffer_.size() < manifest_.signatures_size())
return true;
if (!ExtractSignatureMessage()) {
LOG(ERROR) << "Extract payload signature failed.";
*error = ErrorCode::kDownloadPayloadVerificationError;
return false;
}
DiscardBuffer(true, 0);
// Since we extracted the SignatureMessage we need to advance the
// checkpoint, otherwise we would reload the signature and try to extract
// it again.
CheckpointUpdateProgress();
}
return true;
}
bool DeltaPerformer::IsManifestValid() {
return manifest_valid_;
}
bool DeltaPerformer::ParseManifestPartitions(ErrorCode* error) {
if (major_payload_version_ == kBrilloMajorPayloadVersion) {
partitions_.clear();
for (const PartitionUpdate& partition : manifest_.partitions()) {
partitions_.push_back(partition);
}
manifest_.clear_partitions();
} else if (major_payload_version_ == kChromeOSMajorPayloadVersion) {
LOG(INFO) << "Converting update information from old format.";
PartitionUpdate root_part;
root_part.set_partition_name(kLegacyPartitionNameRoot);
#ifdef __ANDROID__
LOG(WARNING) << "Legacy payload major version provided to an Android "
"build. Assuming no post-install. Please use major version "
"2 or newer.";
root_part.set_run_postinstall(false);
#else
root_part.set_run_postinstall(true);
#endif // __ANDROID__
if (manifest_.has_old_rootfs_info()) {
*root_part.mutable_old_partition_info() = manifest_.old_rootfs_info();
manifest_.clear_old_rootfs_info();
}
if (manifest_.has_new_rootfs_info()) {
*root_part.mutable_new_partition_info() = manifest_.new_rootfs_info();
manifest_.clear_new_rootfs_info();
}
*root_part.mutable_operations() = manifest_.install_operations();
manifest_.clear_install_operations();
partitions_.push_back(std::move(root_part));
PartitionUpdate kern_part;
kern_part.set_partition_name(kLegacyPartitionNameKernel);
kern_part.set_run_postinstall(false);
if (manifest_.has_old_kernel_info()) {
*kern_part.mutable_old_partition_info() = manifest_.old_kernel_info();
manifest_.clear_old_kernel_info();
}
if (manifest_.has_new_kernel_info()) {
*kern_part.mutable_new_partition_info() = manifest_.new_kernel_info();
manifest_.clear_new_kernel_info();
}
*kern_part.mutable_operations() = manifest_.kernel_install_operations();
manifest_.clear_kernel_install_operations();
partitions_.push_back(std::move(kern_part));
}
// Fill in the InstallPlan::partitions based on the partitions from the
// payload.
install_plan_->partitions.clear();
for (const auto& partition : partitions_) {
InstallPlan::Partition install_part;
install_part.name = partition.partition_name();
install_part.run_postinstall =
partition.has_run_postinstall() && partition.run_postinstall();
if (install_part.run_postinstall) {
install_part.postinstall_path =
(partition.has_postinstall_path() ? partition.postinstall_path()
: kPostinstallDefaultScript);
install_part.filesystem_type = partition.filesystem_type();
install_part.postinstall_optional = partition.postinstall_optional();
}
if (partition.has_old_partition_info()) {
const PartitionInfo& info = partition.old_partition_info();
install_part.source_size = info.size();
install_part.source_hash.assign(info.hash().begin(), info.hash().end());
}
if (!partition.has_new_partition_info()) {
LOG(ERROR) << "Unable to get new partition hash info on partition "
<< install_part.name << ".";
*error = ErrorCode::kDownloadNewPartitionInfoError;
return false;
}
const PartitionInfo& info = partition.new_partition_info();
install_part.target_size = info.size();
install_part.target_hash.assign(info.hash().begin(), info.hash().end());
install_plan_->partitions.push_back(install_part);
}
if (!install_plan_->LoadPartitionsFromSlots(boot_control_)) {
LOG(ERROR) << "Unable to determine all the partition devices.";
*error = ErrorCode::kInstallDeviceOpenError;
return false;
}
LogPartitionInfo(partitions_);
return true;
}
bool DeltaPerformer::CanPerformInstallOperation(
const chromeos_update_engine::InstallOperation& operation) {
// If we don't have a data blob we can apply it right away.
if (!operation.has_data_offset() && !operation.has_data_length())
return true;
// See if we have the entire data blob in the buffer
if (operation.data_offset() < buffer_offset_) {
LOG(ERROR) << "we threw away data it seems?";
return false;
}
return (operation.data_offset() + operation.data_length() <=
buffer_offset_ + buffer_.size());
}
bool DeltaPerformer::PerformReplaceOperation(
const InstallOperation& operation) {
CHECK(operation.type() == InstallOperation::REPLACE ||
operation.type() == InstallOperation::REPLACE_BZ ||
operation.type() == InstallOperation::REPLACE_XZ);
// Since we delete data off the beginning of the buffer as we use it,
// the data we need should be exactly at the beginning of the buffer.
TEST_AND_RETURN_FALSE(buffer_offset_ == operation.data_offset());
TEST_AND_RETURN_FALSE(buffer_.size() >= operation.data_length());
// Extract the signature message if it's in this operation.
if (ExtractSignatureMessageFromOperation(operation)) {
// If this is dummy replace operation, we ignore it after extracting the
// signature.
DiscardBuffer(true, 0);
return true;
}
// Setup the ExtentWriter stack based on the operation type.
std::unique_ptr<ExtentWriter> writer = base::MakeUnique<ZeroPadExtentWriter>(
base::MakeUnique<DirectExtentWriter>());
if (operation.type() == InstallOperation::REPLACE_BZ) {
writer.reset(new BzipExtentWriter(std::move(writer)));
} else if (operation.type() == InstallOperation::REPLACE_XZ) {
writer.reset(new XzExtentWriter(std::move(writer)));
}
// Create a vector of extents to pass to the ExtentWriter.
vector<Extent> extents;
for (int i = 0; i < operation.dst_extents_size(); i++) {
extents.push_back(operation.dst_extents(i));
}
TEST_AND_RETURN_FALSE(writer->Init(target_fd_, extents, block_size_));
TEST_AND_RETURN_FALSE(writer->Write(buffer_.data(), operation.data_length()));
TEST_AND_RETURN_FALSE(writer->End());
// Update buffer
DiscardBuffer(true, buffer_.size());
return true;
}
bool DeltaPerformer::PerformZeroOrDiscardOperation(
const InstallOperation& operation) {
CHECK(operation.type() == InstallOperation::DISCARD ||
operation.type() == InstallOperation::ZERO);
// These operations have no blob.
TEST_AND_RETURN_FALSE(!operation.has_data_offset());
TEST_AND_RETURN_FALSE(!operation.has_data_length());
#ifdef BLKZEROOUT
bool attempt_ioctl = true;
int request =
(operation.type() == InstallOperation::ZERO ? BLKZEROOUT : BLKDISCARD);
#else // !defined(BLKZEROOUT)
bool attempt_ioctl = false;
int request = 0;
#endif // !defined(BLKZEROOUT)
brillo::Blob zeros;
for (const Extent& extent : operation.dst_extents()) {
const uint64_t start = extent.start_block() * block_size_;
const uint64_t length = extent.num_blocks() * block_size_;
if (attempt_ioctl) {
int result = 0;
if (target_fd_->BlkIoctl(request, start, length, &result) && result == 0)
continue;
attempt_ioctl = false;
zeros.resize(16 * block_size_);
}
// In case of failure, we fall back to writing 0 to the selected region.
for (uint64_t offset = 0; offset < length; offset += zeros.size()) {
uint64_t chunk_length = min(length - offset,
static_cast<uint64_t>(zeros.size()));
TEST_AND_RETURN_FALSE(
utils::PWriteAll(target_fd_, zeros.data(), chunk_length, start + offset));
}
}
return true;
}
bool DeltaPerformer::PerformMoveOperation(const InstallOperation& operation) {
// Calculate buffer size. Note, this function doesn't do a sliding
// window to copy in case the source and destination blocks overlap.
// If we wanted to do a sliding window, we could program the server
// to generate deltas that effectively did a sliding window.
uint64_t blocks_to_read = 0;
for (int i = 0; i < operation.src_extents_size(); i++)
blocks_to_read += operation.src_extents(i).num_blocks();
uint64_t blocks_to_write = 0;
for (int i = 0; i < operation.dst_extents_size(); i++)
blocks_to_write += operation.dst_extents(i).num_blocks();
DCHECK_EQ(blocks_to_write, blocks_to_read);
brillo::Blob buf(blocks_to_write * block_size_);
// Read in bytes.
ssize_t bytes_read = 0;
for (int i = 0; i < operation.src_extents_size(); i++) {
ssize_t bytes_read_this_iteration = 0;
const Extent& extent = operation.src_extents(i);
const size_t bytes = extent.num_blocks() * block_size_;
TEST_AND_RETURN_FALSE(extent.start_block() != kSparseHole);
TEST_AND_RETURN_FALSE(utils::PReadAll(target_fd_,
&buf[bytes_read],
bytes,
extent.start_block() * block_size_,
&bytes_read_this_iteration));
TEST_AND_RETURN_FALSE(
bytes_read_this_iteration == static_cast<ssize_t>(bytes));
bytes_read += bytes_read_this_iteration;
}
// Write bytes out.
ssize_t bytes_written = 0;
for (int i = 0; i < operation.dst_extents_size(); i++) {
const Extent& extent = operation.dst_extents(i);
const size_t bytes = extent.num_blocks() * block_size_;
TEST_AND_RETURN_FALSE(extent.start_block() != kSparseHole);
TEST_AND_RETURN_FALSE(utils::PWriteAll(target_fd_,
&buf[bytes_written],
bytes,
extent.start_block() * block_size_));
bytes_written += bytes;
}
DCHECK_EQ(bytes_written, bytes_read);
DCHECK_EQ(bytes_written, static_cast<ssize_t>(buf.size()));
return true;
}
namespace {
// Takes |extents| and fills an empty vector |blocks| with a block index for
// each block in |extents|. For example, [(3, 2), (8, 1)] would give [3, 4, 8].
void ExtentsToBlocks(const RepeatedPtrField<Extent>& extents,
vector<uint64_t>* blocks) {
for (const Extent& ext : extents) {
for (uint64_t j = 0; j < ext.num_blocks(); j++)
blocks->push_back(ext.start_block() + j);
}
}
// Takes |extents| and returns the number of blocks in those extents.
uint64_t GetBlockCount(const RepeatedPtrField<Extent>& extents) {
uint64_t sum = 0;
for (const Extent& ext : extents) {
sum += ext.num_blocks();
}
return sum;
}
// Compare |calculated_hash| with source hash in |operation|, return false and
// dump hash and set |error| if don't match.
bool ValidateSourceHash(const brillo::Blob& calculated_hash,
const InstallOperation& operation,
ErrorCode* error) {
brillo::Blob expected_source_hash(operation.src_sha256_hash().begin(),
operation.src_sha256_hash().end());
if (calculated_hash != expected_source_hash) {
LOG(ERROR) << "The hash of the source data on disk for this operation "
<< "doesn't match the expected value. This could mean that the "
<< "delta update payload was targeted for another version, or "
<< "that the source partition was modified after it was "
<< "installed, for example, by mounting a filesystem.";
LOG(ERROR) << "Expected: sha256|hex = "
<< base::HexEncode(expected_source_hash.data(),
expected_source_hash.size());
LOG(ERROR) << "Calculated: sha256|hex = "
<< base::HexEncode(calculated_hash.data(),
calculated_hash.size());
vector<string> source_extents;
for (const Extent& ext : operation.src_extents()) {
source_extents.push_back(
base::StringPrintf("%" PRIu64 ":%" PRIu64,
static_cast<uint64_t>(ext.start_block()),
static_cast<uint64_t>(ext.num_blocks())));
}
LOG(ERROR) << "Operation source (offset:size) in blocks: "
<< base::JoinString(source_extents, ",");
*error = ErrorCode::kDownloadStateInitializationError;
return false;
}
return true;
}
} // namespace
bool DeltaPerformer::PerformSourceCopyOperation(
const InstallOperation& operation, ErrorCode* error) {
if (operation.has_src_length())
TEST_AND_RETURN_FALSE(operation.src_length() % block_size_ == 0);
if (operation.has_dst_length())
TEST_AND_RETURN_FALSE(operation.dst_length() % block_size_ == 0);
uint64_t blocks_to_read = GetBlockCount(operation.src_extents());
uint64_t blocks_to_write = GetBlockCount(operation.dst_extents());
TEST_AND_RETURN_FALSE(blocks_to_write == blocks_to_read);
// Create vectors of all the individual src/dst blocks.
vector<uint64_t> src_blocks;
vector<uint64_t> dst_blocks;
ExtentsToBlocks(operation.src_extents(), &src_blocks);
ExtentsToBlocks(operation.dst_extents(), &dst_blocks);
DCHECK_EQ(src_blocks.size(), blocks_to_read);
DCHECK_EQ(src_blocks.size(), dst_blocks.size());
brillo::Blob buf(block_size_);
ssize_t bytes_read = 0;
HashCalculator source_hasher;
// Read/write one block at a time.
for (uint64_t i = 0; i < blocks_to_read; i++) {
ssize_t bytes_read_this_iteration = 0;
uint64_t src_block = src_blocks[i];
uint64_t dst_block = dst_blocks[i];
// Read in bytes.
TEST_AND_RETURN_FALSE(
utils::PReadAll(source_fd_,
buf.data(),
block_size_,
src_block * block_size_,
&bytes_read_this_iteration));
// Write bytes out.
TEST_AND_RETURN_FALSE(
utils::PWriteAll(target_fd_,
buf.data(),
block_size_,
dst_block * block_size_));
bytes_read += bytes_read_this_iteration;
TEST_AND_RETURN_FALSE(bytes_read_this_iteration ==
static_cast<ssize_t>(block_size_));
if (operation.has_src_sha256_hash())
TEST_AND_RETURN_FALSE(source_hasher.Update(buf.data(), buf.size()));
}
if (operation.has_src_sha256_hash()) {
TEST_AND_RETURN_FALSE(source_hasher.Finalize());
TEST_AND_RETURN_FALSE(
ValidateSourceHash(source_hasher.raw_hash(), operation, error));
}
DCHECK_EQ(bytes_read, static_cast<ssize_t>(blocks_to_read * block_size_));
return true;
}
bool DeltaPerformer::ExtentsToBsdiffPositionsString(
const RepeatedPtrField<Extent>& extents,
uint64_t block_size,
uint64_t full_length,
string* positions_string) {
string ret;
uint64_t length = 0;
for (const Extent& extent : extents) {
int64_t start = extent.start_block() * block_size;
uint64_t this_length =
min(full_length - length,
static_cast<uint64_t>(extent.num_blocks()) * block_size);
ret += base::StringPrintf("%" PRIi64 ":%" PRIu64 ",", start, this_length);
length += this_length;
}
TEST_AND_RETURN_FALSE(length == full_length);
if (!ret.empty())
ret.resize(ret.size() - 1); // Strip trailing comma off
*positions_string = ret;
return true;
}
bool DeltaPerformer::PerformBsdiffOperation(const InstallOperation& operation) {
// Since we delete data off the beginning of the buffer as we use it,
// the data we need should be exactly at the beginning of the buffer.
TEST_AND_RETURN_FALSE(buffer_offset_ == operation.data_offset());
TEST_AND_RETURN_FALSE(buffer_.size() >= operation.data_length());
string input_positions;
TEST_AND_RETURN_FALSE(ExtentsToBsdiffPositionsString(operation.src_extents(),
block_size_,
operation.src_length(),
&input_positions));
string output_positions;
TEST_AND_RETURN_FALSE(ExtentsToBsdiffPositionsString(operation.dst_extents(),
block_size_,
operation.dst_length(),
&output_positions));
TEST_AND_RETURN_FALSE(bsdiff::bspatch(target_path_.c_str(),
target_path_.c_str(),
buffer_.data(),
buffer_.size(),
input_positions.c_str(),
output_positions.c_str()) == 0);
DiscardBuffer(true, buffer_.size());
if (operation.dst_length() % block_size_) {
// Zero out rest of final block.
// TODO(adlr): build this into bspatch; it's more efficient that way.
const Extent& last_extent =
operation.dst_extents(operation.dst_extents_size() - 1);
const uint64_t end_byte =
(last_extent.start_block() + last_extent.num_blocks()) * block_size_;
const uint64_t begin_byte =
end_byte - (block_size_ - operation.dst_length() % block_size_);
brillo::Blob zeros(end_byte - begin_byte);
TEST_AND_RETURN_FALSE(
utils::PWriteAll(target_fd_, zeros.data(), end_byte - begin_byte, begin_byte));
}
return true;
}
bool DeltaPerformer::PerformSourceBsdiffOperation(
const InstallOperation& operation, ErrorCode* error) {
// Since we delete data off the beginning of the buffer as we use it,
// the data we need should be exactly at the beginning of the buffer.
TEST_AND_RETURN_FALSE(buffer_offset_ == operation.data_offset());
TEST_AND_RETURN_FALSE(buffer_.size() >= operation.data_length());
if (operation.has_src_length())
TEST_AND_RETURN_FALSE(operation.src_length() % block_size_ == 0);
if (operation.has_dst_length())
TEST_AND_RETURN_FALSE(operation.dst_length() % block_size_ == 0);
if (operation.has_src_sha256_hash()) {
HashCalculator source_hasher;
const uint64_t kMaxBlocksToRead = 512; // 2MB if block size is 4KB
brillo::Blob buf(kMaxBlocksToRead * block_size_);
for (const Extent& extent : operation.src_extents()) {
for (uint64_t i = 0; i < extent.num_blocks(); i += kMaxBlocksToRead) {
uint64_t blocks_to_read = min(
kMaxBlocksToRead, static_cast<uint64_t>(extent.num_blocks()) - i);
ssize_t bytes_to_read = blocks_to_read * block_size_;
ssize_t bytes_read_this_iteration = 0;
TEST_AND_RETURN_FALSE(
utils::PReadAll(source_fd_, buf.data(), bytes_to_read,
(extent.start_block() + i) * block_size_,
&bytes_read_this_iteration));
TEST_AND_RETURN_FALSE(bytes_read_this_iteration == bytes_to_read);
TEST_AND_RETURN_FALSE(source_hasher.Update(buf.data(), bytes_to_read));
}
}
TEST_AND_RETURN_FALSE(source_hasher.Finalize());
TEST_AND_RETURN_FALSE(
ValidateSourceHash(source_hasher.raw_hash(), operation, error));
}
string input_positions;
TEST_AND_RETURN_FALSE(ExtentsToBsdiffPositionsString(operation.src_extents(),
block_size_,
operation.src_length(),
&input_positions));
string output_positions;
TEST_AND_RETURN_FALSE(ExtentsToBsdiffPositionsString(operation.dst_extents(),
block_size_,
operation.dst_length(),
&output_positions));
TEST_AND_RETURN_FALSE(bsdiff::bspatch(source_path_.c_str(),
target_path_.c_str(),
buffer_.data(),
buffer_.size(),
input_positions.c_str(),
output_positions.c_str()) == 0);
DiscardBuffer(true, buffer_.size());
return true;
}
bool DeltaPerformer::ExtractSignatureMessageFromOperation(
const InstallOperation& operation) {
if (operation.type() != InstallOperation::REPLACE ||
!manifest_.has_signatures_offset() ||
manifest_.signatures_offset() != operation.data_offset()) {
return false;
}
TEST_AND_RETURN_FALSE(manifest_.has_signatures_size() &&
manifest_.signatures_size() == operation.data_length());
TEST_AND_RETURN_FALSE(ExtractSignatureMessage());
return true;
}
bool DeltaPerformer::ExtractSignatureMessage() {
TEST_AND_RETURN_FALSE(signatures_message_data_.empty());
TEST_AND_RETURN_FALSE(buffer_offset_ == manifest_.signatures_offset());
TEST_AND_RETURN_FALSE(buffer_.size() >= manifest_.signatures_size());
signatures_message_data_.assign(
buffer_.begin(),
buffer_.begin() + manifest_.signatures_size());
// Save the signature blob because if the update is interrupted after the
// download phase we don't go through this path anymore. Some alternatives to
// consider:
//
// 1. On resume, re-download the signature blob from the server and re-verify
// it.
//
// 2. Verify the signature as soon as it's received and don't checkpoint the
// blob and the signed sha-256 context.
LOG_IF(WARNING, !prefs_->SetString(kPrefsUpdateStateSignatureBlob,
string(signatures_message_data_.begin(),
signatures_message_data_.end())))
<< "Unable to store the signature blob.";
LOG(INFO) << "Extracted signature data of size "
<< manifest_.signatures_size() << " at "
<< manifest_.signatures_offset();
return true;
}
bool DeltaPerformer::GetPublicKeyFromResponse(base::FilePath *out_tmp_key) {
if (hardware_->IsOfficialBuild() ||
utils::FileExists(public_key_path_.c_str()) ||
install_plan_->public_key_rsa.empty())
return false;
if (!utils::DecodeAndStoreBase64String(install_plan_->public_key_rsa,
out_tmp_key))
return false;
return true;
}
ErrorCode DeltaPerformer::ValidateMetadataSignature(
const brillo::Blob& payload) {
if (payload.size() < metadata_size_ + metadata_signature_size_)
return ErrorCode::kDownloadMetadataSignatureError;
brillo::Blob metadata_signature_blob, metadata_signature_protobuf_blob;
if (!install_plan_->metadata_signature.empty()) {
// Convert base64-encoded signature to raw bytes.
if (!brillo::data_encoding::Base64Decode(
install_plan_->metadata_signature, &metadata_signature_blob)) {
LOG(ERROR) << "Unable to decode base64 metadata signature: "
<< install_plan_->metadata_signature;
return ErrorCode::kDownloadMetadataSignatureError;
}
} else if (major_payload_version_ == kBrilloMajorPayloadVersion) {
metadata_signature_protobuf_blob.assign(payload.begin() + metadata_size_,
payload.begin() + metadata_size_ +
metadata_signature_size_);
}
if (metadata_signature_blob.empty() &&
metadata_signature_protobuf_blob.empty()) {
if (install_plan_->hash_checks_mandatory) {
LOG(ERROR) << "Missing mandatory metadata signature in both Omaha "
<< "response and payload.";
return ErrorCode::kDownloadMetadataSignatureMissingError;
}
LOG(WARNING) << "Cannot validate metadata as the signature is empty";
return ErrorCode::kSuccess;
}
// See if we should use the public RSA key in the Omaha response.
base::FilePath path_to_public_key(public_key_path_);
base::FilePath tmp_key;
if (GetPublicKeyFromResponse(&tmp_key))
path_to_public_key = tmp_key;
ScopedPathUnlinker tmp_key_remover(tmp_key.value());
if (tmp_key.empty())
tmp_key_remover.set_should_remove(false);
LOG(INFO) << "Verifying metadata hash signature using public key: "
<< path_to_public_key.value();
HashCalculator metadata_hasher;
metadata_hasher.Update(payload.data(), metadata_size_);
if (!metadata_hasher.Finalize()) {
LOG(ERROR) << "Unable to compute actual hash of manifest";
return ErrorCode::kDownloadMetadataSignatureVerificationError;
}
brillo::Blob calculated_metadata_hash = metadata_hasher.raw_hash();
PayloadVerifier::PadRSA2048SHA256Hash(&calculated_metadata_hash);
if (calculated_metadata_hash.empty()) {
LOG(ERROR) << "Computed actual hash of metadata is empty.";
return ErrorCode::kDownloadMetadataSignatureVerificationError;
}
if (!metadata_signature_blob.empty()) {
brillo::Blob expected_metadata_hash;
if (!PayloadVerifier::GetRawHashFromSignature(metadata_signature_blob,
path_to_public_key.value(),
&expected_metadata_hash)) {
LOG(ERROR) << "Unable to compute expected hash from metadata signature";
return ErrorCode::kDownloadMetadataSignatureError;
}
if (calculated_metadata_hash != expected_metadata_hash) {
LOG(ERROR) << "Manifest hash verification failed. Expected hash = ";
utils::HexDumpVector(expected_metadata_hash);
LOG(ERROR) << "Calculated hash = ";
utils::HexDumpVector(calculated_metadata_hash);
return ErrorCode::kDownloadMetadataSignatureMismatch;
}
} else {
if (!PayloadVerifier::VerifySignature(metadata_signature_protobuf_blob,
path_to_public_key.value(),
calculated_metadata_hash)) {
LOG(ERROR) << "Manifest hash verification failed.";
return ErrorCode::kDownloadMetadataSignatureMismatch;
}
}
// The autoupdate_CatchBadSignatures test checks for this string in
// log-files. Keep in sync.
LOG(INFO) << "Metadata hash signature matches value in Omaha response.";
return ErrorCode::kSuccess;
}
ErrorCode DeltaPerformer::ValidateManifest() {
// Perform assorted checks to sanity check the manifest, make sure it
// matches data from other sources, and that it is a supported version.
bool has_old_fields =
(manifest_.has_old_kernel_info() || manifest_.has_old_rootfs_info());
for (const PartitionUpdate& partition : manifest_.partitions()) {
has_old_fields = has_old_fields || partition.has_old_partition_info();
}
// The presence of an old partition hash is the sole indicator for a delta
// update.
InstallPayloadType actual_payload_type =
has_old_fields ? InstallPayloadType::kDelta : InstallPayloadType::kFull;
if (install_plan_->payload_type == InstallPayloadType::kUnknown) {
LOG(INFO) << "Detected a '"
<< InstallPayloadTypeToString(actual_payload_type)
<< "' payload.";
install_plan_->payload_type = actual_payload_type;
} else if (install_plan_->payload_type != actual_payload_type) {
LOG(ERROR) << "InstallPlan expected a '"
<< InstallPayloadTypeToString(install_plan_->payload_type)
<< "' payload but the downloaded manifest contains a '"
<< InstallPayloadTypeToString(actual_payload_type)
<< "' payload.";
return ErrorCode::kPayloadMismatchedType;
}
// Check that the minor version is compatible.
if (actual_payload_type == InstallPayloadType::kFull) {
if (manifest_.minor_version() != kFullPayloadMinorVersion) {
LOG(ERROR) << "Manifest contains minor version "
<< manifest_.minor_version()
<< ", but all full payloads should have version "
<< kFullPayloadMinorVersion << ".";
return ErrorCode::kUnsupportedMinorPayloadVersion;
}
} else {
if (manifest_.minor_version() != supported_minor_version_) {
LOG(ERROR) << "Manifest contains minor version "
<< manifest_.minor_version()
<< " not the supported "
<< supported_minor_version_;
return ErrorCode::kUnsupportedMinorPayloadVersion;
}
}
if (major_payload_version_ != kChromeOSMajorPayloadVersion) {
if (manifest_.has_old_rootfs_info() ||
manifest_.has_new_rootfs_info() ||
manifest_.has_old_kernel_info() ||
manifest_.has_new_kernel_info() ||
manifest_.install_operations_size() != 0 ||
manifest_.kernel_install_operations_size() != 0) {
LOG(ERROR) << "Manifest contains deprecated field only supported in "
<< "major payload version 1, but the payload major version is "
<< major_payload_version_;
return ErrorCode::kPayloadMismatchedType;
}
}
// TODO(garnold) we should be adding more and more manifest checks, such as
// partition boundaries etc (see chromium-os:37661).
return ErrorCode::kSuccess;
}
ErrorCode DeltaPerformer::ValidateOperationHash(
const InstallOperation& operation) {
if (!operation.data_sha256_hash().size()) {
if (!operation.data_length()) {
// Operations that do not have any data blob won't have any operation hash
// either. So, these operations are always considered validated since the
// metadata that contains all the non-data-blob portions of the operation
// has already been validated. This is true for both HTTP and HTTPS cases.
return ErrorCode::kSuccess;
}
// No hash is present for an operation that has data blobs. This shouldn't
// happen normally for any client that has this code, because the
// corresponding update should have been produced with the operation
// hashes. So if it happens it means either we've turned operation hash
// generation off in DeltaDiffGenerator or it's a regression of some sort.
// One caveat though: The last operation is a dummy signature operation
// that doesn't have a hash at the time the manifest is created. So we
// should not complaint about that operation. This operation can be
// recognized by the fact that it's offset is mentioned in the manifest.
if (manifest_.signatures_offset() &&
manifest_.signatures_offset() == operation.data_offset()) {
LOG(INFO) << "Skipping hash verification for signature operation "
<< next_operation_num_ + 1;
} else {
if (install_plan_->hash_checks_mandatory) {
LOG(ERROR) << "Missing mandatory operation hash for operation "
<< next_operation_num_ + 1;
return ErrorCode::kDownloadOperationHashMissingError;
}
LOG(WARNING) << "Cannot validate operation " << next_operation_num_ + 1
<< " as there's no operation hash in manifest";
}
return ErrorCode::kSuccess;
}
brillo::Blob expected_op_hash;
expected_op_hash.assign(operation.data_sha256_hash().data(),
(operation.data_sha256_hash().data() +
operation.data_sha256_hash().size()));
HashCalculator operation_hasher;
operation_hasher.Update(buffer_.data(), operation.data_length());
if (!operation_hasher.Finalize()) {
LOG(ERROR) << "Unable to compute actual hash of operation "
<< next_operation_num_;
return ErrorCode::kDownloadOperationHashVerificationError;
}
brillo::Blob calculated_op_hash = operation_hasher.raw_hash();
if (calculated_op_hash != expected_op_hash) {
LOG(ERROR) << "Hash verification failed for operation "
<< next_operation_num_ << ". Expected hash = ";
utils::HexDumpVector(expected_op_hash);
LOG(ERROR) << "Calculated hash over " << operation.data_length()
<< " bytes at offset: " << operation.data_offset() << " = ";
utils::HexDumpVector(calculated_op_hash);
return ErrorCode::kDownloadOperationHashMismatch;
}
return ErrorCode::kSuccess;
}
#define TEST_AND_RETURN_VAL(_retval, _condition) \
do { \
if (!(_condition)) { \
LOG(ERROR) << "VerifyPayload failure: " << #_condition; \
return _retval; \
} \
} while (0);
ErrorCode DeltaPerformer::VerifyPayload(
const string& update_check_response_hash,
const uint64_t update_check_response_size) {
// See if we should use the public RSA key in the Omaha response.
base::FilePath path_to_public_key(public_key_path_);
base::FilePath tmp_key;
if (GetPublicKeyFromResponse(&tmp_key))
path_to_public_key = tmp_key;
ScopedPathUnlinker tmp_key_remover(tmp_key.value());
if (tmp_key.empty())
tmp_key_remover.set_should_remove(false);
LOG(INFO) << "Verifying payload using public key: "
<< path_to_public_key.value();
// Verifies the download size.
TEST_AND_RETURN_VAL(ErrorCode::kPayloadSizeMismatchError,
update_check_response_size ==
metadata_size_ + metadata_signature_size_ +
buffer_offset_);
// Verifies the payload hash.
const string& payload_hash_data = payload_hash_calculator_.hash();
TEST_AND_RETURN_VAL(ErrorCode::kDownloadPayloadVerificationError,
!payload_hash_data.empty());
TEST_AND_RETURN_VAL(ErrorCode::kPayloadHashMismatchError,
payload_hash_data == update_check_response_hash);
// Verifies the signed payload hash.
if (!utils::FileExists(path_to_public_key.value().c_str())) {
LOG(WARNING) << "Not verifying signed delta payload -- missing public key.";
return ErrorCode::kSuccess;
}
TEST_AND_RETURN_VAL(ErrorCode::kSignedDeltaPayloadExpectedError,
!signatures_message_data_.empty());
brillo::Blob hash_data = signed_hash_calculator_.raw_hash();
TEST_AND_RETURN_VAL(ErrorCode::kDownloadPayloadPubKeyVerificationError,
PayloadVerifier::PadRSA2048SHA256Hash(&hash_data));
TEST_AND_RETURN_VAL(ErrorCode::kDownloadPayloadPubKeyVerificationError,
!hash_data.empty());
if (!PayloadVerifier::VerifySignature(
signatures_message_data_, path_to_public_key.value(), hash_data)) {
// The autoupdate_CatchBadSignatures test checks for this string
// in log-files. Keep in sync.
LOG(ERROR) << "Public key verification failed, thus update failed.";
return ErrorCode::kDownloadPayloadPubKeyVerificationError;
}
LOG(INFO) << "Payload hash matches value in payload.";
// At this point, we are guaranteed to have downloaded a full payload, i.e
// the one whose size matches the size mentioned in Omaha response. If any
// errors happen after this, it's likely a problem with the payload itself or
// the state of the system and not a problem with the URL or network. So,
// indicate that to the download delegate so that AU can backoff
// appropriately.
if (download_delegate_)
download_delegate_->DownloadComplete();
return ErrorCode::kSuccess;
}
void DeltaPerformer::DiscardBuffer(bool do_advance_offset,
size_t signed_hash_buffer_size) {
// Update the buffer offset.
if (do_advance_offset)
buffer_offset_ += buffer_.size();
// Hash the content.
payload_hash_calculator_.Update(buffer_.data(), buffer_.size());
signed_hash_calculator_.Update(buffer_.data(), signed_hash_buffer_size);
// Swap content with an empty vector to ensure that all memory is released.
brillo::Blob().swap(buffer_);
}
bool DeltaPerformer::CanResumeUpdate(PrefsInterface* prefs,
const string& update_check_response_hash) {
int64_t next_operation = kUpdateStateOperationInvalid;
if (!(prefs->GetInt64(kPrefsUpdateStateNextOperation, &next_operation) &&
next_operation != kUpdateStateOperationInvalid &&
next_operation > 0))
return false;
string interrupted_hash;
if (!(prefs->GetString(kPrefsUpdateCheckResponseHash, &interrupted_hash) &&
!interrupted_hash.empty() &&
interrupted_hash == update_check_response_hash))
return false;
int64_t resumed_update_failures;
// Note that storing this value is optional, but if it is there it should not
// be more than the limit.
if (prefs->GetInt64(kPrefsResumedUpdateFailures, &resumed_update_failures) &&
resumed_update_failures > kMaxResumedUpdateFailures)
return false;
// Sanity check the rest.
int64_t next_data_offset = -1;
if (!(prefs->GetInt64(kPrefsUpdateStateNextDataOffset, &next_data_offset) &&
next_data_offset >= 0))
return false;
string sha256_context;
if (!(prefs->GetString(kPrefsUpdateStateSHA256Context, &sha256_context) &&
!sha256_context.empty()))
return false;
int64_t manifest_metadata_size = 0;
if (!(prefs->GetInt64(kPrefsManifestMetadataSize, &manifest_metadata_size) &&
manifest_metadata_size > 0))
return false;
int64_t manifest_signature_size = 0;
if (!(prefs->GetInt64(kPrefsManifestSignatureSize,
&manifest_signature_size) &&
manifest_signature_size >= 0))
return false;
return true;
}
bool DeltaPerformer::ResetUpdateProgress(PrefsInterface* prefs, bool quick) {
TEST_AND_RETURN_FALSE(prefs->SetInt64(kPrefsUpdateStateNextOperation,
kUpdateStateOperationInvalid));
if (!quick) {
prefs->SetString(kPrefsUpdateCheckResponseHash, "");
prefs->SetInt64(kPrefsUpdateStateNextDataOffset, -1);
prefs->SetInt64(kPrefsUpdateStateNextDataLength, 0);
prefs->SetString(kPrefsUpdateStateSHA256Context, "");
prefs->SetString(kPrefsUpdateStateSignedSHA256Context, "");
prefs->SetString(kPrefsUpdateStateSignatureBlob, "");
prefs->SetInt64(kPrefsManifestMetadataSize, -1);
prefs->SetInt64(kPrefsManifestSignatureSize, -1);
prefs->SetInt64(kPrefsResumedUpdateFailures, 0);
}
return true;
}
bool DeltaPerformer::CheckpointUpdateProgress() {
Terminator::set_exit_blocked(true);
if (last_updated_buffer_offset_ != buffer_offset_) {
// Resets the progress in case we die in the middle of the state update.
ResetUpdateProgress(prefs_, true);
TEST_AND_RETURN_FALSE(
prefs_->SetString(kPrefsUpdateStateSHA256Context,
payload_hash_calculator_.GetContext()));
TEST_AND_RETURN_FALSE(
prefs_->SetString(kPrefsUpdateStateSignedSHA256Context,
signed_hash_calculator_.GetContext()));
TEST_AND_RETURN_FALSE(prefs_->SetInt64(kPrefsUpdateStateNextDataOffset,
buffer_offset_));
last_updated_buffer_offset_ = buffer_offset_;
if (next_operation_num_ < num_total_operations_) {
size_t partition_index = current_partition_;
while (next_operation_num_ >= acc_num_operations_[partition_index])
partition_index++;
const size_t partition_operation_num = next_operation_num_ - (
partition_index ? acc_num_operations_[partition_index - 1] : 0);
const InstallOperation& op =
partitions_[partition_index].operations(partition_operation_num);
TEST_AND_RETURN_FALSE(prefs_->SetInt64(kPrefsUpdateStateNextDataLength,
op.data_length()));
} else {
TEST_AND_RETURN_FALSE(prefs_->SetInt64(kPrefsUpdateStateNextDataLength,
0));
}
}
TEST_AND_RETURN_FALSE(prefs_->SetInt64(kPrefsUpdateStateNextOperation,
next_operation_num_));
return true;
}
bool DeltaPerformer::PrimeUpdateState() {
CHECK(manifest_valid_);
block_size_ = manifest_.block_size();
int64_t next_operation = kUpdateStateOperationInvalid;
if (!prefs_->GetInt64(kPrefsUpdateStateNextOperation, &next_operation) ||
next_operation == kUpdateStateOperationInvalid ||
next_operation <= 0) {
// Initiating a new update, no more state needs to be initialized.
return true;
}
next_operation_num_ = next_operation;
// Resuming an update -- load the rest of the update state.
int64_t next_data_offset = -1;
TEST_AND_RETURN_FALSE(prefs_->GetInt64(kPrefsUpdateStateNextDataOffset,
&next_data_offset) &&
next_data_offset >= 0);
buffer_offset_ = next_data_offset;
// The signed hash context and the signature blob may be empty if the
// interrupted update didn't reach the signature.
string signed_hash_context;
if (prefs_->GetString(kPrefsUpdateStateSignedSHA256Context,
&signed_hash_context)) {
TEST_AND_RETURN_FALSE(
signed_hash_calculator_.SetContext(signed_hash_context));
}
string signature_blob;
if (prefs_->GetString(kPrefsUpdateStateSignatureBlob, &signature_blob)) {
signatures_message_data_.assign(signature_blob.begin(),
signature_blob.end());
}
string hash_context;
TEST_AND_RETURN_FALSE(prefs_->GetString(kPrefsUpdateStateSHA256Context,
&hash_context) &&
payload_hash_calculator_.SetContext(hash_context));
int64_t manifest_metadata_size = 0;
TEST_AND_RETURN_FALSE(prefs_->GetInt64(kPrefsManifestMetadataSize,
&manifest_metadata_size) &&
manifest_metadata_size > 0);
metadata_size_ = manifest_metadata_size;
int64_t manifest_signature_size = 0;
TEST_AND_RETURN_FALSE(
prefs_->GetInt64(kPrefsManifestSignatureSize, &manifest_signature_size) &&
manifest_signature_size >= 0);
metadata_signature_size_ = manifest_signature_size;
// Advance the download progress to reflect what doesn't need to be
// re-downloaded.
total_bytes_received_ += buffer_offset_;
// Speculatively count the resume as a failure.
int64_t resumed_update_failures;
if (prefs_->GetInt64(kPrefsResumedUpdateFailures, &resumed_update_failures)) {
resumed_update_failures++;
} else {
resumed_update_failures = 1;
}
prefs_->SetInt64(kPrefsResumedUpdateFailures, resumed_update_failures);
return true;
}
} // namespace chromeos_update_engine