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platform_bootable_recovery/bootloader_message/bootloader_message.cpp
Kelvin Zhang c7ebad5fd6 rm -rf non-AB code 
Bug: 324360816
Test: th
Change-Id: I3d82d9031446be355d8a1d077ab83283c7cc769c
2024-04-05 09:49:38 -07:00

367 lines
13 KiB
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/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <bootloader_message/bootloader_message.h>
#include <errno.h>
#include <fcntl.h>
#include <string.h>
#include <optional>
#include <string>
#include <string_view>
#include <vector>
#include <android-base/file.h>
#include <android-base/hex.h>
#include <android-base/logging.h>
#include <android-base/properties.h>
#include <android-base/stringprintf.h>
#include <android-base/unique_fd.h>
#include <fstab/fstab.h>
#ifndef __ANDROID__
#include <cutils/memory.h> // for strlcpy
#endif
using android::fs_mgr::Fstab;
using android::fs_mgr::ReadDefaultFstab;
static std::optional<std::string> g_misc_device_for_test;
// Exposed for test purpose.
void SetMiscBlockDeviceForTest(std::string_view misc_device) {
g_misc_device_for_test = misc_device;
}
std::string get_misc_blk_device(std::string* err) {
if (g_misc_device_for_test.has_value() && !g_misc_device_for_test->empty()) {
return *g_misc_device_for_test;
}
Fstab fstab;
if (!ReadDefaultFstab(&fstab)) {
*err = "failed to read default fstab";
return "";
}
for (const auto& entry : fstab) {
if (entry.mount_point == "/misc") {
return entry.blk_device;
}
}
*err = "failed to find /misc partition";
return "";
}
// In recovery mode, recovery can get started and try to access the misc
// device before the kernel has actually created it.
static bool wait_for_device(const std::string& blk_device, std::string* err) {
int tries = 0;
int ret;
err->clear();
do {
++tries;
struct stat buf;
ret = stat(blk_device.c_str(), &buf);
if (ret == -1) {
*err += android::base::StringPrintf("failed to stat %s try %d: %s\n",
blk_device.c_str(), tries, strerror(errno));
sleep(1);
}
} while (ret && tries < 10);
if (ret) {
*err += android::base::StringPrintf("failed to stat %s\n", blk_device.c_str());
}
return ret == 0;
}
static bool read_misc_partition(void* p, size_t size, const std::string& misc_blk_device,
size_t offset, std::string* err) {
if (!wait_for_device(misc_blk_device, err)) {
return false;
}
android::base::unique_fd fd(open(misc_blk_device.c_str(), O_RDONLY));
if (fd == -1) {
*err = android::base::StringPrintf("failed to open %s: %s", misc_blk_device.c_str(),
strerror(errno));
return false;
}
if (lseek(fd, static_cast<off_t>(offset), SEEK_SET) != static_cast<off_t>(offset)) {
*err = android::base::StringPrintf("failed to lseek %s: %s", misc_blk_device.c_str(),
strerror(errno));
return false;
}
if (!android::base::ReadFully(fd, p, size)) {
*err = android::base::StringPrintf("failed to read %s: %s", misc_blk_device.c_str(),
strerror(errno));
return false;
}
return true;
}
bool write_misc_partition(const void* p, size_t size, const std::string& misc_blk_device,
size_t offset, std::string* err) {
android::base::unique_fd fd(open(misc_blk_device.c_str(), O_WRONLY));
if (fd == -1) {
*err = android::base::StringPrintf("failed to open %s: %s", misc_blk_device.c_str(),
strerror(errno));
return false;
}
if (lseek(fd, static_cast<off_t>(offset), SEEK_SET) != static_cast<off_t>(offset)) {
*err = android::base::StringPrintf("failed to lseek %s: %s", misc_blk_device.c_str(),
strerror(errno));
return false;
}
if (!android::base::WriteFully(fd, p, size)) {
*err = android::base::StringPrintf("failed to write %s: %s", misc_blk_device.c_str(),
strerror(errno));
return false;
}
if (fsync(fd) == -1) {
*err = android::base::StringPrintf("failed to fsync %s: %s", misc_blk_device.c_str(),
strerror(errno));
return false;
}
return true;
}
std::string get_bootloader_message_blk_device(std::string* err) {
std::string misc_blk_device = get_misc_blk_device(err);
if (misc_blk_device.empty()) return "";
if (!wait_for_device(misc_blk_device, err)) return "";
return misc_blk_device;
}
bool read_bootloader_message_from(bootloader_message* boot, const std::string& misc_blk_device,
std::string* err) {
return read_misc_partition(boot, sizeof(*boot), misc_blk_device,
BOOTLOADER_MESSAGE_OFFSET_IN_MISC, err);
}
bool read_bootloader_message(bootloader_message* boot, std::string* err) {
std::string misc_blk_device = get_misc_blk_device(err);
if (misc_blk_device.empty()) {
return false;
}
return read_bootloader_message_from(boot, misc_blk_device, err);
}
bool write_bootloader_message_to(const bootloader_message& boot, const std::string& misc_blk_device,
std::string* err) {
return write_misc_partition(&boot, sizeof(boot), misc_blk_device,
BOOTLOADER_MESSAGE_OFFSET_IN_MISC, err);
}
bool write_bootloader_message(const bootloader_message& boot, std::string* err) {
std::string misc_blk_device = get_misc_blk_device(err);
if (misc_blk_device.empty()) {
return false;
}
return write_bootloader_message_to(boot, misc_blk_device, err);
}
bool clear_bootloader_message(std::string* err) {
bootloader_message boot = {};
LOG(INFO) << "Clearing BCB";
return write_bootloader_message(boot, err);
}
bool write_bootloader_message(const std::vector<std::string>& options, std::string* err) {
bootloader_message boot = {};
update_bootloader_message_in_struct(&boot, options);
return write_bootloader_message(boot, err);
}
bool write_bootloader_message_to(const std::vector<std::string>& options,
const std::string& misc_blk_device, std::string* err) {
bootloader_message boot = {};
update_bootloader_message_in_struct(&boot, options);
return write_bootloader_message_to(boot, misc_blk_device, err);
}
bool update_bootloader_message(const std::vector<std::string>& options, std::string* err) {
bootloader_message boot{};
if (!read_bootloader_message(&boot, err)) {
return false;
}
update_bootloader_message_in_struct(&boot, options);
LOG(INFO) << "Writing BCB " << boot.command << " " << boot.recovery;
return write_bootloader_message(boot, err);
}
bool update_bootloader_message_in_struct(bootloader_message* boot,
const std::vector<std::string>& options) {
if (!boot) return false;
// Replace the command & recovery fields.
memset(boot->command, 0, sizeof(boot->command));
memset(boot->recovery, 0, sizeof(boot->recovery));
strlcpy(boot->command, "boot-recovery", sizeof(boot->command));
std::string recovery = "recovery\n";
for (const auto& s : options) {
recovery += s;
if (s.back() != '\n') {
recovery += '\n';
}
}
strlcpy(boot->recovery, recovery.c_str(), sizeof(boot->recovery));
return true;
}
bool write_reboot_bootloader(std::string* err) {
bootloader_message boot{};
if (!read_bootloader_message(&boot, err)) {
return false;
}
if (boot.command[0] != '\0') {
*err = "Bootloader command pending.";
return false;
}
strlcpy(boot.command, "bootonce-bootloader", sizeof(boot.command));
LOG(INFO) << "Writing BCB cmd: " << boot.command << " args: " << boot.recovery;
return write_bootloader_message(boot, err);
}
bool read_wipe_package(std::string* package_data, size_t size, std::string* err) {
std::string misc_blk_device = get_misc_blk_device(err);
if (misc_blk_device.empty()) {
return false;
}
package_data->resize(size);
return read_misc_partition(&(*package_data)[0], size, misc_blk_device,
WIPE_PACKAGE_OFFSET_IN_MISC, err);
}
bool write_wipe_package(const std::string& package_data, std::string* err) {
std::string misc_blk_device = get_misc_blk_device(err);
if (misc_blk_device.empty()) {
return false;
}
static constexpr size_t kMaximumWipePackageSize =
SYSTEM_SPACE_OFFSET_IN_MISC - WIPE_PACKAGE_OFFSET_IN_MISC;
if (package_data.size() > kMaximumWipePackageSize) {
*err = "Wipe package size " + std::to_string(package_data.size()) + " exceeds " +
std::to_string(kMaximumWipePackageSize) + " bytes";
return false;
}
return write_misc_partition(package_data.data(), package_data.size(), misc_blk_device,
WIPE_PACKAGE_OFFSET_IN_MISC, err);
}
static bool ValidateSystemSpaceRegion(size_t offset, size_t size, std::string* err) {
if (size <= SYSTEM_SPACE_SIZE_IN_MISC && offset <= (SYSTEM_SPACE_SIZE_IN_MISC - size)) {
return true;
}
*err = android::base::StringPrintf("Out of bound access (offset %zu size %zu)", offset, size);
return false;
}
static bool ReadMiscPartitionSystemSpace(void* data, size_t size, size_t offset, std::string* err) {
if (!ValidateSystemSpaceRegion(offset, size, err)) {
return false;
}
auto misc_blk_device = get_misc_blk_device(err);
if (misc_blk_device.empty()) {
return false;
}
return read_misc_partition(data, size, misc_blk_device, SYSTEM_SPACE_OFFSET_IN_MISC + offset,
err);
}
static bool WriteMiscPartitionSystemSpace(const void* data, size_t size, size_t offset,
std::string* err) {
if (!ValidateSystemSpaceRegion(offset, size, err)) {
return false;
}
auto misc_blk_device = get_misc_blk_device(err);
if (misc_blk_device.empty()) {
return false;
}
return write_misc_partition(data, size, misc_blk_device, SYSTEM_SPACE_OFFSET_IN_MISC + offset,
err);
}
bool ReadMiscVirtualAbMessage(misc_virtual_ab_message* message, std::string* err) {
return ReadMiscPartitionSystemSpace(message, sizeof(*message),
offsetof(misc_system_space_layout, virtual_ab_message), err);
}
bool WriteMiscVirtualAbMessage(const misc_virtual_ab_message& message, std::string* err) {
return WriteMiscPartitionSystemSpace(&message, sizeof(message),
offsetof(misc_system_space_layout, virtual_ab_message), err);
}
bool ReadMiscMemtagMessage(misc_memtag_message* message, std::string* err) {
return ReadMiscPartitionSystemSpace(message, sizeof(*message),
offsetof(misc_system_space_layout, memtag_message), err);
}
bool WriteMiscMemtagMessage(const misc_memtag_message& message, std::string* err) {
return WriteMiscPartitionSystemSpace(&message, sizeof(message),
offsetof(misc_system_space_layout, memtag_message), err);
}
bool ReadMiscKcmdlineMessage(misc_kcmdline_message* message, std::string* err) {
return ReadMiscPartitionSystemSpace(message, sizeof(*message),
offsetof(misc_system_space_layout, kcmdline_message), err);
}
bool WriteMiscKcmdlineMessage(const misc_kcmdline_message& message, std::string* err) {
return WriteMiscPartitionSystemSpace(&message, sizeof(message),
offsetof(misc_system_space_layout, kcmdline_message), err);
}
bool ReadMiscControlMessage(misc_control_message* message, std::string* err) {
return ReadMiscPartitionSystemSpace(message, sizeof(*message),
offsetof(misc_system_space_layout, control_message), err);
}
bool WriteMiscControlMessage(const misc_control_message& message, std::string* err) {
return WriteMiscPartitionSystemSpace(&message, sizeof(message),
offsetof(misc_system_space_layout, control_message), err);
}
bool CheckReservedSystemSpaceEmpty(bool* empty, std::string* err) {
constexpr size_t kReservedSize = SYSTEM_SPACE_SIZE_IN_MISC - sizeof(misc_system_space_layout);
uint8_t space[kReservedSize];
if (!ReadMiscPartitionSystemSpace(&space, kReservedSize, sizeof(misc_system_space_layout), err)) {
return false;
}
*empty = space[0] == 0 && 0 == memcmp(space, space + 1, kReservedSize - 1);
if (!*empty) {
*err = android::base::HexString(space, kReservedSize);
}
return true;
}
extern "C" bool write_reboot_bootloader(void) {
std::string err;
return write_reboot_bootloader(&err);
}
extern "C" bool write_bootloader_message(const char* options) {
std::string err;
return write_bootloader_message({options}, &err);
}
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