Merge "Dump the root digest of hashtree for dm-verity partitions" (055abbb4) · Commits · e / os / android_system_core

fs_mgr/fs_mgr.cpp

+8 −7

Original line number	Diff line number	Diff line
		@@ -2231,16 +2231,16 @@ bool fs_mgr_is_verity_enabled(const FstabEntry& entry) {
		return false;
		}

		std::string fs_mgr_get_hashtree_algorithm(const android::fs_mgr::FstabEntry& entry) {
		std::optional<HashtreeInfo> fs_mgr_get_hashtree_info(const android::fs_mgr::FstabEntry& entry) {
		if (!entry.fs_mgr_flags.verify && !entry.fs_mgr_flags.avb) {
		return "";
		return {};
		}
		DeviceMapper& dm = DeviceMapper::Instance();
		std::string device = GetVerityDeviceName(entry);

		std::vector<DeviceMapper::TargetInfo> table;
		if (dm.GetState(device) == DmDeviceState::INVALID \|\| !dm.GetTableInfo(device, &table)) {
		return "";
		return {};
		}
		for (const auto& target : table) {
		if (strcmp(target.spec.target_type, "verity") != 0) {
		@@ -2256,14 +2256,15 @@ std::string fs_mgr_get_hashtree_algorithm(const android::fs_mgr::FstabEntry& ent
		std::vector<std::string> tokens = android::base::Split(target.data, " \t\r\n");
		if (tokens[0] != "0" && tokens[0] != "1") {
		LOG(WARNING) << "Unrecognized device mapper version in " << target.data;
		return "";
		return {};
		}

		// Hashtree algorithm is the 8th token in the output
		return android::base::Trim(tokens[7]);
		// Hashtree algorithm & root digest are the 8th & 9th token in the output.
		return HashtreeInfo{.algorithm = android::base::Trim(tokens[7]),
		.root_digest = android::base::Trim(tokens[8])};
		}

		return "";
		return {};
		}

		bool fs_mgr_verity_is_check_at_most_once(const android::fs_mgr::FstabEntry& entry) {

fs_mgr/include/fs_mgr.h

+11 −3

Original line number	Diff line number	Diff line
		@@ -22,6 +22,7 @@
		#include <linux/dm-ioctl.h>

		#include <functional>
		#include <optional>
		#include <string>

		#include <fstab/fstab.h>
		@@ -68,6 +69,13 @@ struct MountAllResult {
		bool userdata_mounted;
		};

		struct HashtreeInfo {
		// The hash algorithm used to build the merkle tree.
		std::string algorithm;
		// The root digest of the merkle tree.
		std::string root_digest;
		};

		// fs_mgr_mount_all() updates fstab entries that reference device-mapper.
		// Returns a \|MountAllResult\|. The first element is one of the FS_MNG_MNTALL_* return codes
		// defined above, and the second element tells whether this call to fs_mgr_mount_all was responsible
		@@ -88,9 +96,9 @@ int fs_mgr_do_tmpfs_mount(const char *n_name);
		bool fs_mgr_load_verity_state(int* mode);
		// Returns true if verity is enabled on this particular FstabEntry.
		bool fs_mgr_is_verity_enabled(const android::fs_mgr::FstabEntry& entry);
		// Returns the hash algorithm used to build the hashtree of this particular FstabEntry. Returns an
		// empty string if the input isn't a dm-verity entry, or if there is an error.
		std::string fs_mgr_get_hashtree_algorithm(const android::fs_mgr::FstabEntry& entry);
		// Returns the verity hashtree information of this particular FstabEntry. Returns std::nullopt
		// if the input isn't a dm-verity entry, or if there is an error.
		std::optional<HashtreeInfo> fs_mgr_get_hashtree_info(const android::fs_mgr::FstabEntry& entry);

		bool fs_mgr_swapon_all(const android::fs_mgr::Fstab& fstab);
		bool fs_mgr_update_logical_partition(android::fs_mgr::FstabEntry* entry);

init/builtins.cpp

+5 −3

Original line number	Diff line number	Diff line
		@@ -894,9 +894,11 @@ static Result<void> do_verity_update_state(const BuiltinArguments& args) {
		std::string partition = entry.mount_point == "/" ? "system" : Basename(entry.mount_point);
		SetProperty("partition." + partition + ".verified", std::to_string(mode));

		std::string hash_alg = fs_mgr_get_hashtree_algorithm(entry);
		if (!hash_alg.empty()) {
		SetProperty("partition." + partition + ".verified.hash_alg", hash_alg);
		auto hashtree_info = fs_mgr_get_hashtree_info(entry);
		if (hashtree_info) {
		SetProperty("partition." + partition + ".verified.hash_alg", hashtree_info->algorithm);
		SetProperty("partition." + partition + ".verified.root_digest",
		hashtree_info->root_digest);
		}
		}