From 6faf0265c9b58db2c15b53f6d29025629d52f882 Mon Sep 17 00:00:00 2001 From: Yabin Cui Date: Thu, 9 Jun 2016 14:09:39 -0700 Subject: Verify wipe package when wiping A/B device in recovery. To increase the security of wiping A/B devices, let uncrypt write wipe package in misc partition. Then recovery verifies the wipe package before wiping the device. Bug: 29159185 Change-Id: I186691bab1928d3dc036bc5542abd64a81bc2168 --- uncrypt/bootloader_message_writer.cpp | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) (limited to 'uncrypt/bootloader_message_writer.cpp') diff --git a/uncrypt/bootloader_message_writer.cpp b/uncrypt/bootloader_message_writer.cpp index 3bb106aa0..42df31efa 100644 --- a/uncrypt/bootloader_message_writer.cpp +++ b/uncrypt/bootloader_message_writer.cpp @@ -58,7 +58,7 @@ static std::string get_misc_blk_device(std::string* err) { return record->blk_device; } -static bool write_bootloader_message(const bootloader_message& boot, std::string* err) { +static bool write_misc_partition(const void* p, size_t size, size_t misc_offset, std::string* err) { std::string misc_blk_device = get_misc_blk_device(err); if (misc_blk_device.empty()) { return false; @@ -69,11 +69,18 @@ static bool write_bootloader_message(const bootloader_message& boot, std::string strerror(errno)); return false; } - if (!android::base::WriteFully(fd.get(), &boot, sizeof(boot))) { + if (lseek(fd.get(), static_cast(misc_offset), SEEK_SET) != + static_cast(misc_offset)) { + *err = android::base::StringPrintf("failed to lseek %s: %s", misc_blk_device.c_str(), + strerror(errno)); + return false; + } + if (!android::base::WriteFully(fd.get(), p, size)) { *err = android::base::StringPrintf("failed to write %s: %s", misc_blk_device.c_str(), strerror(errno)); return false; } + // TODO: O_SYNC and fsync duplicates each other? if (fsync(fd.get()) == -1) { *err = android::base::StringPrintf("failed to fsync %s: %s", misc_blk_device.c_str(), @@ -83,6 +90,10 @@ static bool write_bootloader_message(const bootloader_message& boot, std::string return true; } +static bool write_bootloader_message(const bootloader_message& boot, std::string* err) { + return write_misc_partition(&boot, sizeof(boot), BOOTLOADER_MESSAGE_OFFSET_IN_MISC, err); +} + bool clear_bootloader_message(std::string* err) { bootloader_message boot = {}; return write_bootloader_message(boot, err); @@ -101,6 +112,11 @@ bool write_bootloader_message(const std::vector& options, std::stri return write_bootloader_message(boot, err); } +bool write_wipe_package(const std::string& package_data, std::string* err) { + return write_misc_partition(package_data.data(), package_data.size(), + WIPE_PACKAGE_OFFSET_IN_MISC, err); +} + extern "C" bool write_bootloader_message(const char* options) { std::string err; return write_bootloader_message({options}, &err); -- cgit v1.2.3