diff options
Diffstat (limited to '')
-rw-r--r-- | install.cpp | 203 |
1 files changed, 187 insertions, 16 deletions
diff --git a/install.cpp b/install.cpp index 3871271f7..dd6ed81cf 100644 --- a/install.cpp +++ b/install.cpp @@ -17,6 +17,7 @@ #include <ctype.h> #include <errno.h> #include <fcntl.h> +#include <inttypes.h> #include <limits.h> #include <string.h> #include <sys/stat.h> @@ -24,6 +25,8 @@ #include <unistd.h> #include <chrono> +#include <limits> +#include <map> #include <string> #include <vector> @@ -32,6 +35,7 @@ #include <android-base/parseint.h> #include <android-base/stringprintf.h> #include <android-base/strings.h> +#include <cutils/properties.h> #include <ziparchive/zip_archive.h> #include "common.h" @@ -44,6 +48,8 @@ #include "verifier.h" #define ASSUMED_UPDATE_BINARY_NAME "META-INF/com/google/android/update-binary" +static constexpr const char* AB_OTA_PAYLOAD_PROPERTIES = "payload_properties.txt"; +static constexpr const char* AB_OTA_PAYLOAD = "payload.bin"; #define PUBLIC_KEYS_FILE "/res/keys" static constexpr const char* METADATA_PATH = "META-INF/com/android/metadata"; static constexpr const char* UNCRYPT_STATUS = "/cache/recovery/uncrypt_status"; @@ -118,13 +124,146 @@ static void read_source_target_build(ZipArchiveHandle zip, std::vector<std::stri } } -// If the package contains an update binary, extract it and run it. +// Extract the update binary from the open zip archive |zip| located at |path| +// and store into |cmd| the command line that should be called. The |status_fd| +// is the file descriptor the child process should use to report back the +// progress of the update. static int -try_update_binary(const char* path, ZipArchiveHandle zip, bool* wipe_cache, - std::vector<std::string>& log_buffer, int retry_count) +update_binary_command(const char* path, ZipArchiveHandle zip, int retry_count, + int status_fd, std::vector<std::string>* cmd); + +#ifdef AB_OTA_UPDATER + +// Parses the metadata of the OTA package in |zip| and checks whether we are +// allowed to accept this A/B package. Downgrading is not allowed unless +// explicitly enabled in the package and only for incremental packages. +static int check_newer_ab_build(ZipArchiveHandle zip) { - read_source_target_build(zip, log_buffer); + std::string metadata_str; + if (!read_metadata_from_package(zip, &metadata_str)) { + return INSTALL_CORRUPT; + } + std::map<std::string, std::string> metadata; + for (const std::string& line : android::base::Split(metadata_str, "\n")) { + size_t eq = line.find('='); + if (eq != std::string::npos) { + metadata[line.substr(0, eq)] = line.substr(eq + 1); + } + } + char value[PROPERTY_VALUE_MAX]; + + property_get("ro.product.device", value, ""); + const std::string& pkg_device = metadata["pre-device"]; + if (pkg_device != value || pkg_device.empty()) { + LOG(ERROR) << "Package is for product " << pkg_device << " but expected " << value; + return INSTALL_ERROR; + } + + // We allow the package to not have any serialno, but if it has a non-empty + // value it should match. + property_get("ro.serialno", value, ""); + const std::string& pkg_serial_no = metadata["serialno"]; + if (!pkg_serial_no.empty() && pkg_serial_no != value) { + LOG(ERROR) << "Package is for serial " << pkg_serial_no; + return INSTALL_ERROR; + } + + if (metadata["ota-type"] != "AB") { + LOG(ERROR) << "Package is not A/B"; + return INSTALL_ERROR; + } + + // Incremental updates should match the current build. + property_get("ro.build.version.incremental", value, ""); + const std::string& pkg_pre_build = metadata["pre-build-incremental"]; + if (!pkg_pre_build.empty() && pkg_pre_build != value) { + LOG(ERROR) << "Package is for source build " << pkg_pre_build << " but expected " << value; + return INSTALL_ERROR; + } + property_get("ro.build.fingerprint", value, ""); + const std::string& pkg_pre_build_fingerprint = metadata["pre-build"]; + if (!pkg_pre_build_fingerprint.empty() && + pkg_pre_build_fingerprint != value) { + LOG(ERROR) << "Package is for source build " << pkg_pre_build_fingerprint + << " but expected " << value; + return INSTALL_ERROR; + } + + // Check for downgrade version. + int64_t build_timestamp = property_get_int64( + "ro.build.date.utc", std::numeric_limits<int64_t>::max()); + int64_t pkg_post_timestamp = 0; + // We allow to full update to the same version we are running, in case there + // is a problem with the current copy of that version. + if (metadata["post-timestamp"].empty() || + !android::base::ParseInt(metadata["post-timestamp"].c_str(), + &pkg_post_timestamp) || + pkg_post_timestamp < build_timestamp) { + if (metadata["ota-downgrade"] != "yes") { + LOG(ERROR) << "Update package is older than the current build, expected a build " + "newer than timestamp " << build_timestamp << " but package has " + "timestamp " << pkg_post_timestamp << " and downgrade not allowed."; + return INSTALL_ERROR; + } + if (pkg_pre_build_fingerprint.empty()) { + LOG(ERROR) << "Downgrade package must have a pre-build version set, not allowed."; + return INSTALL_ERROR; + } + } + + return 0; +} + +static int +update_binary_command(const char* path, ZipArchiveHandle zip, int retry_count, + int status_fd, std::vector<std::string>* cmd) +{ + int ret = check_newer_ab_build(zip); + if (ret) { + return ret; + } + // For A/B updates we extract the payload properties to a buffer and obtain + // the RAW payload offset in the zip file. + ZipString property_name(AB_OTA_PAYLOAD_PROPERTIES); + ZipEntry properties_entry; + if (FindEntry(zip, property_name, &properties_entry) != 0) { + LOG(ERROR) << "Can't find " << AB_OTA_PAYLOAD_PROPERTIES; + return INSTALL_CORRUPT; + } + std::vector<uint8_t> payload_properties( + properties_entry.uncompressed_length); + if (ExtractToMemory(zip, &properties_entry, payload_properties.data(), + properties_entry.uncompressed_length) != 0) { + LOG(ERROR) << "Can't extract " << AB_OTA_PAYLOAD_PROPERTIES; + return INSTALL_CORRUPT; + } + + ZipString payload_name(AB_OTA_PAYLOAD); + ZipEntry payload_entry; + if (FindEntry(zip, payload_name, &payload_entry) != 0) { + LOG(ERROR) << "Can't find " << AB_OTA_PAYLOAD; + return INSTALL_CORRUPT; + } + long payload_offset = payload_entry.offset; + *cmd = { + "/sbin/update_engine_sideload", + android::base::StringPrintf("--payload=file://%s", path), + android::base::StringPrintf("--offset=%ld", payload_offset), + "--headers=" + std::string(payload_properties.begin(), + payload_properties.end()), + android::base::StringPrintf("--status_fd=%d", status_fd), + }; + return 0; +} + +#else // !AB_OTA_UPDATER + +static int +update_binary_command(const char* path, ZipArchiveHandle zip, int retry_count, + int status_fd, std::vector<std::string>* cmd) +{ + // On traditional updates we extract the update binary from the package. ZipString binary_name(ASSUMED_UPDATE_BINARY_NAME); ZipEntry binary_entry; if (FindEntry(zip, binary_name, &binary_entry) != 0) { @@ -147,9 +286,36 @@ try_update_binary(const char* path, ZipArchiveHandle zip, bool* wipe_cache, return INSTALL_ERROR; } + *cmd = { + binary, + EXPAND(RECOVERY_API_VERSION), // defined in Android.mk + std::to_string(status_fd), + path, + }; + if (retry_count > 0) + cmd->push_back("retry"); + return 0; +} +#endif // !AB_OTA_UPDATER + +// If the package contains an update binary, extract it and run it. +static int +try_update_binary(const char* path, ZipArchiveHandle zip, bool* wipe_cache, + std::vector<std::string>& log_buffer, int retry_count) +{ + read_source_target_build(zip, log_buffer); + int pipefd[2]; pipe(pipefd); + std::vector<std::string> args; + int ret = update_binary_command(path, zip, retry_count, pipefd[1], &args); + if (ret) { + close(pipefd[0]); + close(pipefd[1]); + return ret; + } + // When executing the update binary contained in the package, the // arguments passed are: // @@ -199,22 +365,27 @@ try_update_binary(const char* path, ZipArchiveHandle zip, bool* wipe_cache, // update attempt. // - const char* args[6]; - args[0] = binary; - args[1] = EXPAND(RECOVERY_API_VERSION); // defined in Android.mk - char temp[16]; - snprintf(temp, sizeof(temp), "%d", pipefd[1]); - args[2] = temp; - args[3] = path; - args[4] = retry_count > 0 ? "retry" : NULL; - args[5] = NULL; + // Convert the vector to a NULL-terminated char* array suitable for execv. + const char* chr_args[args.size() + 1]; + chr_args[args.size()] = NULL; + for (size_t i = 0; i < args.size(); i++) { + chr_args[i] = args[i].c_str(); + } pid_t pid = fork(); + + if (pid == -1) { + close(pipefd[0]); + close(pipefd[1]); + PLOG(ERROR) << "Failed to fork update binary"; + return INSTALL_ERROR; + } + if (pid == 0) { umask(022); close(pipefd[0]); - execv(binary, const_cast<char**>(args)); - fprintf(stdout, "E:Can't run %s (%s)\n", binary, strerror(errno)); + execv(chr_args[0], const_cast<char**>(chr_args)); + fprintf(stdout, "E:Can't run %s (%s)\n", chr_args[0], strerror(errno)); _exit(-1); } close(pipefd[1]); @@ -371,7 +542,7 @@ install_package(const char* path, bool* wipe_cache, const char* install_file, if (!android::base::ReadFileToString(UNCRYPT_STATUS, &uncrypt_status)) { PLOG(WARNING) << "failed to read uncrypt status"; } else if (!android::base::StartsWith(uncrypt_status, "uncrypt_")) { - LOG(WARNING) << "corrupted uncrypt_status: " << uncrypt_status; + PLOG(WARNING) << "corrupted uncrypt_status: " << uncrypt_status; } else { log_buffer.push_back(android::base::Trim(uncrypt_status)); } |