Merge "update_verifier should read dm wrapped partition" (c44c4791) · Commits · e / os / android_bootable_recovery

update_verifier/update_verifier.cpp

+64 −6

Original line number	Diff line number	Diff line
		@@ -30,6 +30,7 @@
		* verifier reaches the end after the verification.
		*/

		#include <dirent.h>
		#include <errno.h>
		#include <fcntl.h>
		#include <stdio.h>
		@@ -52,14 +53,71 @@ using android::hardware::boot::V1_0::BoolResult;
		using android::hardware::boot::V1_0::CommandResult;

		constexpr auto CARE_MAP_FILE = "/data/ota_package/care_map.txt";
		constexpr auto DM_PATH_PREFIX = "/sys/block/";
		constexpr auto DM_PATH_SUFFIX = "/dm/name";
		constexpr auto DEV_PATH = "/dev/block/";
		constexpr int BLOCKSIZE = 4096;

		static bool read_blocks(const std::string& blk_device_prefix, const std::string& range_str) {
		std::string slot_suffix = android::base::GetProperty("ro.boot.slot_suffix", "");
		std::string blk_device = blk_device_prefix + slot_suffix;
		android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(blk_device.c_str(), O_RDONLY)));
		// Find directories in format of "/sys/block/dm-X".
		static int dm_name_filter(const dirent* de) {
		if (android::base::StartsWith(de->d_name, "dm-")) {
		return 1;
		}
		return 0;
		}

		static bool read_blocks(const std::string& blk_device, const std::string& range_str) {
		// Parse the partition in the end of the block_device string.
		// Here is one example: "/dev/block/bootdevice/by-name/system"
		std::string partition;
		if (android::base::EndsWith(blk_device, "system")) {
		partition = "system";
		} else if (android::base::EndsWith(blk_device, "vendor")) {
		partition = "vendor";
		} else {
		LOG(ERROR) << "Failed to parse partition string in " << blk_device;
		return false;
		}

		// Iterate the content of "/sys/block/dm-X/dm/name". If it matches "system"
		// (or "vendor"), then dm-X is a dm-wrapped system/vendor partition.
		// Afterwards, update_verifier will read every block on the care_map_file of
		// "/dev/block/dm-X" to ensure the partition's integrity.
		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;
		}
		if (n == 0) {
		LOG(ERROR) << "dm block device not found for " << partition;
		return false;
		}

		std::string dm_block_device;
		while (n--) {
		std::string path = DM_PATH_PREFIX + std::string(namelist[n]->d_name) + DM_PATH_SUFFIX;
		std::string content;
		if (!android::base::ReadFileToString(path, &content)) {
		PLOG(WARNING) << "Failed to read " << path;
		} else if (android::base::Trim(content) == partition) {
		dm_block_device = DEV_PATH + std::string(namelist[n]->d_name);
		while (n--) {
		free(namelist[n]);
		}
		break;
		}
		free(namelist[n]);
		}
		free(namelist);

		if (dm_block_device.empty()) {
		LOG(ERROR) << "Failed to find dm block device for " << partition;
		return false;
		}
		android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(dm_block_device.c_str(), O_RDONLY)));
		if (fd.get() == -1) {
		PLOG(ERROR) << "Error reading partition " << blk_device;
		PLOG(ERROR) << "Error reading " << dm_block_device << " for partition " << partition;
		return false;
		}

		@@ -100,7 +158,7 @@ static bool read_blocks(const std::string& blk_device_prefix, const std::string&
		blk_count += (range_end - range_start);
		}

		LOG(INFO) << "Finished reading " << blk_count << " blocks on " << blk_device;
		LOG(INFO) << "Finished reading " << blk_count << " blocks on " << dm_block_device;
		return true;
		}