/*
* 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_twrp/bootloader_message.h>
#include <errno.h>
#include <fcntl.h>
#include <string.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/system_properties.h>
#include <string>
#include <vector>
static std::string misc_blkdev;
void set_misc_device(const char* name) {
misc_blkdev = name;
}
static std::string get_misc_blk_device(std::string* err) {
*err = "";
return misc_blkdev;
}
// 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) {
char buffer[2048];
sprintf(buffer, "failed to stat %s try %d: %s\n",
blk_device.c_str(), tries, strerror(errno));
*err += buffer;
/*
*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 += "failed to stat " + blk_device + "\n";
/*
*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;
}
int fd(open(misc_blk_device.c_str(), O_RDONLY));
if (fd < 0) {
*err = "failed to open " + misc_blk_device + ": ";
*err += strerror(errno);
/*
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 = "failed to lseek " + misc_blk_device + ": ";
*err += strerror(errno);
close(fd);
/*
*err = android::base::StringPrintf("failed to lseek %s: %s", misc_blk_device.c_str(),
strerror(errno));
*/
return false;
}
if ((size_t)read(fd, p, size) != size) {
*err = "failed to read " + misc_blk_device + ": ";
*err += strerror(errno);
close(fd);
/*
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;
}
close(fd);
return true;
}
static bool write_misc_partition(const void* p, size_t size, size_t offset, std::string* err) {
std::string misc_blk_device = get_misc_blk_device(err);
if (misc_blk_device.empty()) {
*err = "no misc device set";
return false;
}
int fd = (open(misc_blk_device.c_str(), O_WRONLY | O_SYNC));
if (fd == -1) {
*err = "failed to open " + misc_blk_device + ": ";
*err += strerror(errno);
/*
static 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 = "failed to lseek " + misc_blk_device + ": ";
*err += strerror(errno);
close(fd);
/*
*err = android::base::StringPrintf("failed to lseek %s: %s", misc_blk_device.c_str(),
strerror(errno));
*/
return false;
}
if ((size_t)write(fd, p, size) != size) {
*err = "failed to write " + misc_blk_device + ": ";
*err += strerror(errno);
close(fd);
/*
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;
}
// TODO: O_SYNC and fsync duplicates each other?
if (fsync(fd) == -1) {
*err = "failed to fsync " + misc_blk_device + ": ";
*err += strerror(errno);
close(fd);
/*
if (fsync(fd) == -1) {
*err = android::base::StringPrintf("failed to fsync %s: %s", misc_blk_device.c_str(),
strerror(errno));
*/
return false;
}
close(fd);
return true;
}
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, __unused const std::string& misc_blk_device,
std::string* err) {
return write_misc_partition(&boot, sizeof(boot),
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);
}
// libc++ in 5.1 does not know how to handle a std::string* so this craziness is needed
bool clear_bootloader_message(void* err) {
std::string &s = *(static_cast<std::string*>(err));
return clear_bootloader_message(&s);
}
bool clear_bootloader_message(std::string* err) {
bootloader_message boot = {};
return write_bootloader_message(boot, err);
}
bool write_bootloader_message(const std::vector<std::string>& options, std::string* err) {
bootloader_message boot = {};
strlcpy(boot.command, "boot-recovery", sizeof(boot.command));
strlcpy(boot.recovery, "recovery\n", sizeof(boot.recovery));
for (const auto& s : options) {
strlcat(boot.recovery, s.c_str(), sizeof(boot.recovery));
if (s.substr(s.size() - 1) != "\n") {
strlcat(boot.recovery, "\n", sizeof(boot.recovery));
}
}
return write_bootloader_message(boot, 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;
}
// Zero out the entire fields.
memset(boot.command, 0, sizeof(boot.command));
memset(boot.recovery, 0, sizeof(boot.recovery));
strlcpy(boot.command, "boot-recovery", sizeof(boot.command));
strlcpy(boot.recovery, "recovery\n", sizeof(boot.recovery));
for (const auto& s : options) {
strlcat(boot.recovery, s.c_str(), sizeof(boot.recovery));
if (s.back() != '\n') {
strlcat(boot.recovery, "\n", sizeof(boot.recovery));
}
}
return write_bootloader_message(boot, err);
}
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));
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;
}
return write_misc_partition(package_data.data(), package_data.size(),
WIPE_PACKAGE_OFFSET_IN_MISC, err);
}
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;
bootloader_message boot = {};
memcpy(&boot, options, sizeof(boot));
return write_bootloader_message(boot, &err);
}
static const char *COMMAND_FILE = "/cache/recovery/command";
static const int MAX_ARG_LENGTH = 4096;
static const int MAX_ARGS = 100;
// command line args come from, in decreasing precedence:
// - the actual command line
// - the bootloader control block (one per line, after "recovery")
// - the contents of COMMAND_FILE (one per line)
void
get_args(int *argc, char ***argv) {
bootloader_message boot = {};
std::string err;
if (!read_bootloader_message(&boot, &err)) {
printf("%s\n", err.c_str());
// If fails, leave a zeroed bootloader_message.
memset(&boot, 0, sizeof(boot));
}
//stage = strndup(boot.stage, sizeof(boot.stage));
if (boot.command[0] != 0 && boot.command[0] != (char)255) {
printf("Boot command: %.*s\n", (int)sizeof(boot.command), boot.command);
}
if (boot.status[0] != 0 && boot.status[0] != (char)255) {
printf("Boot status: %.*s\n", (int)sizeof(boot.status), boot.status);
}
// --- if arguments weren't supplied, look in the bootloader control block
if (*argc <= 1) {
boot.recovery[sizeof(boot.recovery) - 1] = '\0'; // Ensure termination
const char *arg = strtok(boot.recovery, "\n");
if (arg != NULL && !strcmp(arg, "recovery")) {
*argv = (char **) malloc(sizeof(char *) * MAX_ARGS);
(*argv)[0] = strdup(arg);
for (*argc = 1; *argc < MAX_ARGS; ++*argc) {
if ((arg = strtok(NULL, "\n")) == NULL) break;
// if the device does not have an own recovery key combo we just want to open TWRP after
// walking through the factory reset screen - without actually doing a factory reset
#ifdef IGNORE_MISC_WIPE_DATA
if (!strcmp(arg, "--wipe_data")) {
(*argv)[*argc] = NULL;
*argc = *argc -1;
printf("Bootloader arg \"%s\" ignored because TWRP was compiled with TW_IGNORE_MISC_WIPE_DATA\n", arg);
continue;
}
#endif
(*argv)[*argc] = strdup(arg);
}
printf("Got arguments from boot message\n");
} else if (boot.recovery[0] != 0 && boot.recovery[0] != (char)255) {
printf("Bad boot message\n\"%.20s\"\n", boot.recovery);
}
}
// --- if that doesn't work, try the command file (if we have /cache).
if (*argc <= 1/* && has_cache*/) {
FILE *fp = fopen(COMMAND_FILE, "r");
if (fp != NULL) {
char *token;
char *argv0 = (*argv)[0];
*argv = (char **) malloc(sizeof(char *) * MAX_ARGS);
(*argv)[0] = argv0; // use the same program name
char buf[MAX_ARG_LENGTH];
for (*argc = 1; *argc < MAX_ARGS; ++*argc) {
if (!fgets(buf, sizeof(buf), fp)) break;
token = strtok(buf, "\r\n");
if (token != NULL) {
(*argv)[*argc] = strdup(token); // Strip newline.
} else {
--*argc;
}
}
fclose(fp);
printf("Got arguments from %s\n", COMMAND_FILE);
}
}
// --> write the arguments we have back into the bootloader control block
// always boot into recovery after this (until finish_recovery() is called)
strlcpy(boot.command, "boot-recovery", sizeof(boot.command));
strlcpy(boot.recovery, "recovery\n", sizeof(boot.recovery));
int i;
for (i = 1; i < *argc; ++i) {
strlcat(boot.recovery, (*argv)[i], sizeof(boot.recovery));
strlcat(boot.recovery, "\n", sizeof(boot.recovery));
}
if (!write_bootloader_message(boot, &err)) {
printf("%s\n", err.c_str());
}
}
