tequilaOS/platform_bootable_recovery
2
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

Refactor update_verifier into a class

Browse source 
The refactor separates out the parsing of care_map and the actual
verification of the partitions. Moreover, it skips the verification in case
of a format error in the care map.

Also, the parsing of care_map now uses the suffix of the file to
tell if it has the protobuf format or the plain text format.

Bug: 115740187
Test: unit test pass
Change-Id: I7aa32004db02af1deb7bfdc6f5bd7921eb7883e5
This commit is contained in:
Tianjie Xu 2018-09-19 15:45:28 -07:00
parent 6c8c7c1975
commit 446b64b659
5 changed files with 183 additions and 103 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

63
tests/component/update_verifier_test.cpp
View file

@ -29,19 +29,29 @@
#include "care_map.pb.h"
using namespace std::string_literals;
class UpdateVerifierTest : public ::testing::Test {
protected:
void SetUp() override {
std::string verity_mode = android::base::GetProperty("ro.boot.veritymode", "");
verity_supported = android::base::EqualsIgnoreCase(verity_mode, "enforcing");
care_map_pb_ = care_map_dir_.path + "/care_map.pb"s;
care_map_txt_ = care_map_dir_.path + "/care_map.txt"s;
}
void TearDown() override {
unlink(care_map_pb_.c_str());
unlink(care_map_txt_.c_str());
}
// Returns a serialized string of the proto3 message according to the given partition info.
std::string ConstructProto(
std::vector<std::unordered_map<std::string, std::string>>& partitions) {
UpdateVerifier::CareMap result;
recovery_update_verifier::CareMap result;
for (const auto& partition : partitions) {
UpdateVerifier::CareMap::PartitionInfo info;
recovery_update_verifier::CareMap::PartitionInfo info;
if (partition.find("name") != partition.end()) {
info.set_name(partition.at("name"));
}
@ -59,12 +69,16 @@ class UpdateVerifierTest : public ::testing::Test {
}
bool verity_supported;
TemporaryFile care_map_file;
UpdateVerifier verifier_;
TemporaryDir care_map_dir_;
std::string care_map_pb_;
std::string care_map_txt_;
};
TEST_F(UpdateVerifierTest, verify_image_no_care_map) {
// Non-existing care_map is allowed.
ASSERT_TRUE(verify_image("/doesntexist"));
ASSERT_FALSE(verifier_.ParseCareMap("/doesntexist"));
}
TEST_F(UpdateVerifierTest, verify_image_smoke) {
@ -75,25 +89,27 @@ TEST_F(UpdateVerifierTest, verify_image_smoke) {
}
std::string content = "system\n2,0,1";
ASSERT_TRUE(android::base::WriteStringToFile(content, care_map_file.path));
ASSERT_TRUE(verify_image(care_map_file.path));
ASSERT_TRUE(android::base::WriteStringToFile(content, care_map_txt_));
ASSERT_TRUE(verifier_.ParseCareMap(care_map_txt_));
ASSERT_TRUE(verifier_.VerifyPartitions());
// Leading and trailing newlines should be accepted.
ASSERT_TRUE(android::base::WriteStringToFile("\n" + content + "\n\n", care_map_file.path));
ASSERT_TRUE(verify_image(care_map_file.path));
ASSERT_TRUE(android::base::WriteStringToFile("\n" + content + "\n\n", care_map_txt_));
ASSERT_TRUE(verifier_.ParseCareMap(care_map_txt_));
ASSERT_TRUE(verifier_.VerifyPartitions());
}
TEST_F(UpdateVerifierTest, verify_image_empty_care_map) {
ASSERT_FALSE(verify_image(care_map_file.path));
ASSERT_FALSE(verifier_.ParseCareMap(care_map_txt_));
}
TEST_F(UpdateVerifierTest, verify_image_wrong_lines) {
// The care map file can have only 2 / 4 / 6 lines.
ASSERT_TRUE(android::base::WriteStringToFile("line1", care_map_file.path));
ASSERT_FALSE(verify_image(care_map_file.path));
ASSERT_TRUE(android::base::WriteStringToFile("line1", care_map_txt_));
ASSERT_FALSE(verifier_.ParseCareMap(care_map_txt_));
ASSERT_TRUE(android::base::WriteStringToFile("line1\nline2\nline3", care_map_file.path));
ASSERT_FALSE(verify_image(care_map_file.path));
ASSERT_TRUE(android::base::WriteStringToFile("line1\nline2\nline3", care_map_txt_));
ASSERT_FALSE(verifier_.ParseCareMap(care_map_txt_));
}
TEST_F(UpdateVerifierTest, verify_image_malformed_care_map) {
@ -104,8 +120,8 @@ TEST_F(UpdateVerifierTest, verify_image_malformed_care_map) {
}
std::string content = "system\n2,1,0";
ASSERT_TRUE(android::base::WriteStringToFile(content, care_map_file.path));
ASSERT_FALSE(verify_image(care_map_file.path));
ASSERT_TRUE(android::base::WriteStringToFile(content, care_map_txt_));
ASSERT_FALSE(verifier_.ParseCareMap(care_map_txt_));
}
TEST_F(UpdateVerifierTest, verify_image_legacy_care_map) {
@ -116,8 +132,8 @@ TEST_F(UpdateVerifierTest, verify_image_legacy_care_map) {
}
std::string content = "/dev/block/bootdevice/by-name/system\n2,1,0";
ASSERT_TRUE(android::base::WriteStringToFile(content, care_map_file.path));
ASSERT_TRUE(verify_image(care_map_file.path));
ASSERT_TRUE(android::base::WriteStringToFile(content, care_map_txt_));
ASSERT_FALSE(verifier_.ParseCareMap(care_map_txt_));
}
TEST_F(UpdateVerifierTest, verify_image_protobuf_care_map_smoke) {
@ -132,8 +148,9 @@ TEST_F(UpdateVerifierTest, verify_image_protobuf_care_map_smoke) {
};
std::string proto = ConstructProto(partitions);
ASSERT_TRUE(android::base::WriteStringToFile(proto, care_map_file.path));
ASSERT_TRUE(verify_image(care_map_file.path));
ASSERT_TRUE(android::base::WriteStringToFile(proto, care_map_pb_));
ASSERT_TRUE(verifier_.ParseCareMap(care_map_pb_));
ASSERT_TRUE(verifier_.VerifyPartitions());
}
TEST_F(UpdateVerifierTest, verify_image_protobuf_care_map_missing_name) {
@ -148,8 +165,8 @@ TEST_F(UpdateVerifierTest, verify_image_protobuf_care_map_missing_name) {
};
std::string proto = ConstructProto(partitions);
ASSERT_TRUE(android::base::WriteStringToFile(proto, care_map_file.path));
ASSERT_FALSE(verify_image(care_map_file.path));
ASSERT_TRUE(android::base::WriteStringToFile(proto, care_map_pb_));
ASSERT_FALSE(verifier_.ParseCareMap(care_map_pb_));
}
TEST_F(UpdateVerifierTest, verify_image_protobuf_care_map_bad_ranges) {
@ -164,6 +181,6 @@ TEST_F(UpdateVerifierTest, verify_image_protobuf_care_map_bad_ranges) {
};
std::string proto = ConstructProto(partitions);
ASSERT_TRUE(android::base::WriteStringToFile(proto, care_map_file.path));
ASSERT_FALSE(verify_image(care_map_file.path));
ASSERT_TRUE(android::base::WriteStringToFile(proto, care_map_pb_));
ASSERT_FALSE(verifier_.ParseCareMap(care_map_pb_));
}

5
update_verifier/Android.bp
View file

@ -15,9 +15,8 @@
cc_defaults {
name: "update_verifier_defaults",
cflags: [
"-Wall",
"-Werror",
defaults: [
"recovery_defaults",
],
local_include_dirs: [

2
update_verifier/care_map.proto
View file

@ -16,7 +16,7 @@
syntax = "proto3";
package UpdateVerifier;
package recovery_update_verifier;
option optimize_for = LITE_RUNTIME;
message CareMap {

42
update_verifier/include/update_verifier/update_verifier.h
View file

@ -16,17 +16,45 @@
#pragma once
#include <map>
#include <string>
#include <vector>
int update_verifier(int argc, char** argv);
#include "otautil/rangeset.h"
// The update verifier performs verification upon the first boot to a new slot on A/B devices.
// During the verification, it reads all the blocks in the care_map. And if a failure happens,
// it rejects the current boot and triggers a fallback.
// Returns true to indicate a passing verification (or the error should be ignored); Otherwise
// returns false on fatal errors, where we should reject the current boot and trigger a fallback.
// This function tries to process the care_map.txt as protobuf message; and falls back to use the
// plain text format if the parse failed.
//
// Note that update_verifier should be backward compatible to not reject care_map.txt from old
// releases, which could otherwise fail to boot into the new release. For example, we've changed
// the care_map format between N and O. An O update_verifier would fail to work with N care_map.txt.
// This could be a result of sideloading an O OTA while the device having a pending N update.
bool verify_image(const std::string& care_map_name);
int update_verifier(int argc, char** argv);
// The UpdateVerifier parses the content in the care map, and continues to verify the
// partitions by reading the cared blocks if there's no format error in the file. Otherwise,
// it should skip the verification to avoid bricking the device.
class UpdateVerifier {
public:
// This function tries to process the care_map.pb as protobuf message; and falls back to use
// care_map.txt if the pb format file doesn't exist. If the parsing succeeds, put the result of
// the pair <partition_name, ranges> into the |partition_map_|.
bool ParseCareMap(const std::string& file_name = "");
// Verifies the new boot by reading all the cared blocks for partitions in |partition_map_|.
bool VerifyPartitions();
private:
// Parses the legacy care_map.txt in plain text format.
bool ParseCareMapPlainText(const std::string& content);
// Finds all the dm-enabled partitions, and returns a map of <partition_name, block_device>.
std::map<std::string, std::string> FindDmPartitions();
// Returns true if we successfully read the blocks in |ranges| of the |dm_block_device|.
bool ReadBlocks(const std::string partition_name, const std::string& dm_block_device,
const RangeSet& ranges);
std::map<std::string, RangeSet> partition_map_;
};

174
update_verifier/update_verifier.cpp
View file

@ -48,8 +48,6 @@
#include <algorithm>
#include <future>
#include <string>
#include <vector>
#include <android-base/file.h>
#include <android-base/logging.h>
@ -61,7 +59,6 @@
#include <cutils/android_reboot.h>
#include "care_map.pb.h"
#include "otautil/rangeset.h"
using android::sp;
using android::hardware::boot::V1_0::IBootControl;
@ -76,29 +73,25 @@ static int dm_name_filter(const dirent* de) {
return 0;
}
static bool read_blocks(const std::string& partition, const std::string& range_str) {
if (partition != "system" && partition != "vendor" && partition != "product") {
LOG(ERROR) << "Invalid partition name \"" << partition << "\"";
return false;
}
// Iterate the content of "/sys/block/dm-X/dm/name". If it matches one of "system", "vendor" or
// "product", then dm-X is a dm-wrapped device for that target. We will later read all the
// ("cared") blocks from "/dev/block/dm-X" to ensure the target partition's integrity.
// Iterate the content of "/sys/block/dm-X/dm/name" and find all the dm-wrapped block devices.
// We will later read all the ("cared") blocks from "/dev/block/dm-X" to ensure the target
// partition's integrity.
std::map<std::string, std::string> UpdateVerifier::FindDmPartitions() {
static constexpr auto DM_PATH_PREFIX = "/sys/block/";
dirent** namelist;
int n = scandir(DM_PATH_PREFIX, &namelist, dm_name_filter, alphasort);
if (n == -1) {
PLOG(ERROR) << "Failed to scan dir " << DM_PATH_PREFIX;
return false;
return {};
}
if (n == 0) {
LOG(ERROR) << "dm block device not found for " << partition;
return false;
LOG(ERROR) << "No dm block device found.";
return {};
}
static constexpr auto DM_PATH_SUFFIX = "/dm/name";
static constexpr auto DEV_PATH = "/dev/block/";
std::string dm_block_device;
std::map<std::string, std::string> dm_block_devices;
while (n--) {
std::string path = DM_PATH_PREFIX + std::string(namelist[n]->d_name) + DM_PATH_SUFFIX;
std::string content;
@ -110,33 +103,18 @@ static bool read_blocks(const std::string& partition, const std::string& range_s
if (dm_block_name == "vroot") {
dm_block_name = "system";
}
if (dm_block_name == partition) {
dm_block_device = DEV_PATH + std::string(namelist[n]->d_name);
while (n--) {
free(namelist[n]);
}
break;
}
dm_block_devices.emplace(dm_block_name, DEV_PATH + std::string(namelist[n]->d_name));
}
free(namelist[n]);
}
free(namelist);
if (dm_block_device.empty()) {
LOG(ERROR) << "Failed to find dm block device for " << partition;
return false;
}
// For block range string, first integer 'count' equals 2 * total number of valid ranges,
// followed by 'count' number comma separated integers. Every two integers reprensent a
// block range with the first number included in range but second number not included.
// For example '4,64536,65343,74149,74150' represents: [64536,65343) and [74149,74150).
RangeSet ranges = RangeSet::Parse(range_str);
if (!ranges) {
LOG(ERROR) << "Error parsing RangeSet string " << range_str;
return false;
}
return dm_block_devices;
}
bool UpdateVerifier::ReadBlocks(const std::string partition_name,
const std::string& dm_block_device, const RangeSet& ranges) {
// RangeSet::Split() splits the ranges into multiple groups with same number of blocks (except for
// the last group).
size_t thread_num = std::thread::hardware_concurrency() ?: 4;
@ -144,10 +122,10 @@ static bool read_blocks(const std::string& partition, const std::string& range_s
std::vector<std::future<bool>> threads;
for (const auto& group : groups) {
auto thread_func = [&group, &dm_block_device, &partition]() {
auto thread_func = [&group, &dm_block_device, &partition_name]() {
android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(dm_block_device.c_str(), O_RDONLY)));
if (fd.get() == -1) {
PLOG(ERROR) << "Error reading " << dm_block_device << " for partition " << partition;
PLOG(ERROR) << "Error reading " << dm_block_device << " for partition " << partition_name;
return false;
}
@ -155,9 +133,7 @@ static bool read_blocks(const std::string& partition, const std::string& range_s
std::vector<uint8_t> buf(1024 * kBlockSize);
size_t block_count = 0;
for (const auto& range : group) {
size_t range_start = range.first;
size_t range_end = range.second;
for (const auto& [range_start, range_end] : group) {
if (lseek64(fd.get(), static_cast<off64_t>(range_start) * kBlockSize, SEEK_SET) == -1) {
PLOG(ERROR) << "lseek to " << range_start << " failed";
return false;
@ -190,26 +166,20 @@ static bool read_blocks(const std::string& partition, const std::string& range_s
return ret;
}
static bool process_care_map_plain_text(const std::string& care_map_contents) {
// care_map file has up to six lines, where every two lines make a pair. Within each pair, the
// first line has the partition name (e.g. "system"), while the second line holds the ranges of
// all the blocks to verify.
std::vector<std::string> lines =
android::base::Split(android::base::Trim(care_map_contents), "\n");
if (lines.size() != 2 && lines.size() != 4 && lines.size() != 6) {
LOG(ERROR) << "Invalid lines in care_map: found " << lines.size()
<< " lines, expecting 2 or 4 or 6 lines.";
bool UpdateVerifier::VerifyPartitions() {
auto dm_block_devices = FindDmPartitions();
if (dm_block_devices.empty()) {
LOG(ERROR) << "No dm-enabled block device is found.";
return false;
}
for (size_t i = 0; i < lines.size(); i += 2) {
// We're seeing an N care_map.txt. Skip the verification since it's not compatible with O
// update_verifier (the last few metadata blocks can't be read via device mapper).
if (android::base::StartsWith(lines[i], "/dev/block/")) {
LOG(WARNING) << "Found legacy care_map.txt; skipped.";
return true;
for (const auto& [partition_name, ranges] : partition_map_) {
if (dm_block_devices.find(partition_name) == dm_block_devices.end()) {
LOG(ERROR) << "Failed to find dm block device for " << partition_name;
return false;
}
if (!read_blocks(lines[i], lines[i+1])) {
if (!ReadBlocks(partition_name, dm_block_devices.at(partition_name), ranges)) {
return false;
}
}
@ -217,45 +187,109 @@ static bool process_care_map_plain_text(const std::string& care_map_contents) {
return true;
}
bool verify_image(const std::string& care_map_name) {
bool UpdateVerifier::ParseCareMapPlainText(const std::string& content) {
// care_map file has up to six lines, where every two lines make a pair. Within each pair, the
// first line has the partition name (e.g. "system"), while the second line holds the ranges of
// all the blocks to verify.
auto lines = android::base::Split(android::base::Trim(content), "\n");
if (lines.size() != 2 && lines.size() != 4 && lines.size() != 6) {
LOG(WARNING) << "Invalid lines in care_map: found " << lines.size()
<< " lines, expecting 2 or 4 or 6 lines.";
return false;
}
for (size_t i = 0; i < lines.size(); i += 2) {
const std::string& partition_name = lines[i];
const std::string& range_str = lines[i + 1];
// We're seeing an N care_map.txt. Skip the verification since it's not compatible with O
// update_verifier (the last few metadata blocks can't be read via device mapper).
if (android::base::StartsWith(partition_name, "/dev/block/")) {
LOG(WARNING) << "Found legacy care_map.txt; skipped.";
return false;
}
// For block range string, first integer 'count' equals 2 * total number of valid ranges,
// followed by 'count' number comma separated integers. Every two integers reprensent a
// block range with the first number included in range but second number not included.
// For example '4,64536,65343,74149,74150' represents: [64536,65343) and [74149,74150).
RangeSet ranges = RangeSet::Parse(range_str);
if (!ranges) {
LOG(WARNING) << "Error parsing RangeSet string " << range_str;
return false;
}
partition_map_.emplace(partition_name, ranges);
}
return true;
}
bool UpdateVerifier::ParseCareMap(const std::string& file_name) {
partition_map_.clear();
std::string care_map_name = file_name;
if (care_map_name.empty()) {
std::string care_map_prefix = "/data/ota_package/care_map";
care_map_name = care_map_prefix + ".pb";
if (access(care_map_name.c_str(), R_OK) == -1) {
LOG(WARNING) << care_map_name
<< " doesn't exist, falling back to read the care_map in plain text format.";
care_map_name = care_map_prefix + ".txt";
}
}
android::base::unique_fd care_map_fd(TEMP_FAILURE_RETRY(open(care_map_name.c_str(), O_RDONLY)));
// If the device is flashed before the current boot, it may not have care_map.txt in
// /data/ota_package. To allow the device to continue booting in this situation, we should
// print a warning and skip the block verification.
if (care_map_fd.get() == -1) {
PLOG(WARNING) << "Failed to open " << care_map_name;
return true;
return false;
}
std::string file_content;
if (!android::base::ReadFdToString(care_map_fd.get(), &file_content)) {
PLOG(ERROR) << "Failed to read " << care_map_name;
PLOG(WARNING) << "Failed to read " << care_map_name;
return false;
}
if (file_content.empty()) {
LOG(ERROR) << "Unexpected empty care map";
LOG(WARNING) << "Unexpected empty care map";
return false;
}
UpdateVerifier::CareMap care_map;
// Falls back to use the plain text version if we cannot parse the file as protobuf message.
if (android::base::EndsWith(care_map_name, ".txt")) {
return ParseCareMapPlainText(file_content);
}
recovery_update_verifier::CareMap care_map;
if (!care_map.ParseFromString(file_content)) {
return process_care_map_plain_text(file_content);
LOG(WARNING) << "Failed to parse " << care_map_name << " in protobuf format.";
return false;
}
for (const auto& partition : care_map.partitions()) {
if (partition.name().empty()) {
LOG(ERROR) << "Unexpected empty partition name.";
LOG(WARNING) << "Unexpected empty partition name.";
return false;
}
if (partition.ranges().empty()) {
LOG(ERROR) << "Unexpected block ranges for partition " << partition.name();
LOG(WARNING) << "Unexpected block ranges for partition " << partition.name();
return false;
}
if (!read_blocks(partition.name(), partition.ranges())) {
RangeSet ranges = RangeSet::Parse(partition.ranges());
if (!ranges) {
LOG(WARNING) << "Error parsing RangeSet string " << partition.ranges();
return false;
}
// TODO(xunchang) compare the fingerprint of the partition.
partition_map_.emplace(partition.name(), ranges);
}
if (partition_map_.empty()) {
LOG(WARNING) << "No partition to verify";
return false;
}
return true;
@ -308,8 +342,10 @@ int update_verifier(int argc, char** argv) {
}
if (!skip_verification) {
static constexpr auto CARE_MAP_FILE = "/data/ota_package/care_map.txt";
if (!verify_image(CARE_MAP_FILE)) {
UpdateVerifier verifier;
if (!verifier.ParseCareMap()) {
LOG(WARNING) << "Failed to parse the care map file, skipping verification";
} else if (!verifier.VerifyPartitions()) {
LOG(ERROR) << "Failed to verify all blocks in care map file.";
return reboot_device();
}