Merge "fastboot: copy AVB footer on boot image to end of partition" (626ca916) · Commits · e / os / android_system_core

fastboot/fastboot.cpp

+59 −9

Original line number	Diff line number	Diff line
		@@ -992,10 +992,69 @@ static bool has_vbmeta_partition() {
		fb->GetVar("partition-type:vbmeta_b", &partition_type) == fastboot::SUCCESS;
		}

		static std::string fb_fix_numeric_var(std::string var) {
		// Some bootloaders (angler, for example), send spurious leading whitespace.
		var = android::base::Trim(var);
		// Some bootloaders (hammerhead, for example) use implicit hex.
		// This code used to use strtol with base 16.
		if (!android::base::StartsWith(var, "0x")) var = "0x" + var;
		return var;
		}

		static void copy_boot_avb_footer(const std::string& partition, struct fastboot_buffer* buf) {
		if (buf->sz < AVB_FOOTER_SIZE) {
		return;
		}

		std::string partition_size_str;
		if (fb->GetVar("partition-size:" + partition, &partition_size_str) != fastboot::SUCCESS) {
		die("cannot get boot partition size");
		}

		partition_size_str = fb_fix_numeric_var(partition_size_str);
		int64_t partition_size;
		if (!android::base::ParseInt(partition_size_str, &partition_size)) {
		die("Couldn't parse partition size '%s'.", partition_size_str.c_str());
		}
		if (partition_size == buf->sz) {
		return;
		}
		if (partition_size < buf->sz) {
		die("boot partition is smaller than boot image");
		}

		std::string data;
		if (!android::base::ReadFdToString(buf->fd, &data)) {
		die("Failed reading from boot");
		}

		uint64_t footer_offset = buf->sz - AVB_FOOTER_SIZE;
		if (0 != data.compare(footer_offset, AVB_FOOTER_MAGIC_LEN, AVB_FOOTER_MAGIC)) {
		return;
		}

		int fd = make_temporary_fd("boot rewriting");
		if (!android::base::WriteStringToFd(data, fd)) {
		die("Failed writing to modified boot");
		}
		lseek(fd, partition_size - AVB_FOOTER_SIZE, SEEK_SET);
		if (!android::base::WriteStringToFd(data.substr(footer_offset), fd)) {
		die("Failed copying AVB footer in boot");
		}
		close(buf->fd);
		buf->fd = fd;
		buf->sz = partition_size;
		lseek(fd, 0, SEEK_SET);
		}

		static void flash_buf(const std::string& partition, struct fastboot_buffer *buf)
		{
		sparse_file** s;

		if (partition == "boot" \|\| partition == "boot_a" \|\| partition == "boot_b") {
		copy_boot_avb_footer(partition, buf);
		}

		// Rewrite vbmeta if that's what we're flashing and modification has been requested.
		if (g_disable_verity \|\| g_disable_verification) {
		if (partition == "vbmeta" \|\| partition == "vbmeta_a" \|\| partition == "vbmeta_b") {
		@@ -1491,15 +1550,6 @@ static void do_oem_command(const std::string& cmd, std::vector<std::string>* arg
		fb->RawCommand(command, "");
		}

		static std::string fb_fix_numeric_var(std::string var) {
		// Some bootloaders (angler, for example), send spurious leading whitespace.
		var = android::base::Trim(var);
		// Some bootloaders (hammerhead, for example) use implicit hex.
		// This code used to use strtol with base 16.
		if (!android::base::StartsWith(var, "0x")) var = "0x" + var;
		return var;
		}

		static unsigned fb_get_flash_block_size(std::string name) {
		std::string sizeString;
		if (fb->GetVar(name, &sizeString) != fastboot::SUCCESS \|\| sizeString.empty()) {