/*
* Copyright (C) 2008 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 <errno.h>
#include <fcntl.h>
#include <inttypes.h>
#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <fs_mgr.h>
#include "bootloader.h"
#include "common.h"
#include "mtdutils/mtdutils.h"
#include "roots.h"
#include "unique_fd.h"
static int get_bootloader_message_mtd(bootloader_message* out, const Volume* v);
static int set_bootloader_message_mtd(const bootloader_message* in, const Volume* v);
static int get_bootloader_message_block(bootloader_message* out, const Volume* v);
static int set_bootloader_message_block(const bootloader_message* in, const Volume* v);
int get_bootloader_message(bootloader_message* out) {
Volume* v = volume_for_path("/misc");
if (v == nullptr) {
LOGE("Cannot load volume /misc!\n");
return -1;
}
if (strcmp(v->fs_type, "mtd") == 0) {
return get_bootloader_message_mtd(out, v);
} else if (strcmp(v->fs_type, "emmc") == 0) {
return get_bootloader_message_block(out, v);
}
LOGE("unknown misc partition fs_type \"%s\"\n", v->fs_type);
return -1;
}
int set_bootloader_message(const bootloader_message* in) {
Volume* v = volume_for_path("/misc");
if (v == nullptr) {
LOGE("Cannot load volume /misc!\n");
return -1;
}
if (strcmp(v->fs_type, "mtd") == 0) {
return set_bootloader_message_mtd(in, v);
} else if (strcmp(v->fs_type, "emmc") == 0) {
return set_bootloader_message_block(in, v);
}
LOGE("unknown misc partition fs_type \"%s\"\n", v->fs_type);
return -1;
}
// ------------------------------
// for misc partitions on MTD
// ------------------------------
static const int MISC_PAGES = 3; // number of pages to save
static const int MISC_COMMAND_PAGE = 1; // bootloader command is this page
static int get_bootloader_message_mtd(bootloader_message* out,
const Volume* v) {
size_t write_size;
mtd_scan_partitions();
const MtdPartition* part = mtd_find_partition_by_name(v->blk_device);
if (part == nullptr || mtd_partition_info(part, nullptr, nullptr, &write_size)) {
LOGE("failed to find \"%s\"\n", v->blk_device);
return -1;
}
MtdReadContext* read = mtd_read_partition(part);
if (read == nullptr) {
LOGE("failed to open \"%s\": %s\n", v->blk_device, strerror(errno));
return -1;
}
const ssize_t size = write_size * MISC_PAGES;
char data[size];
ssize_t r = mtd_read_data(read, data, size);
if (r != size) LOGE("failed to read \"%s\": %s\n", v->blk_device, strerror(errno));
mtd_read_close(read);
if (r != size) return -1;
memcpy(out, &data[write_size * MISC_COMMAND_PAGE], sizeof(*out));
return 0;
}
static int set_bootloader_message_mtd(const bootloader_message* in,
const Volume* v) {
size_t write_size;
mtd_scan_partitions();
const MtdPartition* part = mtd_find_partition_by_name(v->blk_device);
if (part == nullptr || mtd_partition_info(part, nullptr, nullptr, &write_size)) {
LOGE("failed to find \"%s\"\n", v->blk_device);
return -1;
}
MtdReadContext* read = mtd_read_partition(part);
if (read == nullptr) {
LOGE("failed to open \"%s\": %s\n", v->blk_device, strerror(errno));
return -1;
}
ssize_t size = write_size * MISC_PAGES;
char data[size];
ssize_t r = mtd_read_data(read, data, size);
if (r != size) LOGE("failed to read \"%s\": %s\n", v->blk_device, strerror(errno));
mtd_read_close(read);
if (r != size) return -1;
memcpy(&data[write_size * MISC_COMMAND_PAGE], in, sizeof(*in));
MtdWriteContext* write = mtd_write_partition(part);
if (write == nullptr) {
LOGE("failed to open \"%s\": %s\n", v->blk_device, strerror(errno));
return -1;
}
if (mtd_write_data(write, data, size) != size) {
LOGE("failed to write \"%s\": %s\n", v->blk_device, strerror(errno));
mtd_write_close(write);
return -1;
}
if (mtd_write_close(write)) {
LOGE("failed to finish \"%s\": %s\n", v->blk_device, strerror(errno));
return -1;
}
LOGI("Set boot command \"%s\"\n", in->command[0] != 255 ? in->command : "");
return 0;
}
// ------------------------------------
// for misc partitions on block devices
// ------------------------------------
static void wait_for_device(const char* fn) {
int tries = 0;
int ret;
do {
++tries;
struct stat buf;
ret = stat(fn, &buf);
if (ret == -1) {
printf("failed to stat \"%s\" try %d: %s\n", fn, tries, strerror(errno));
sleep(1);
}
} while (ret && tries < 10);
if (ret) {
printf("failed to stat \"%s\"\n", fn);
}
}
static int get_bootloader_message_block(bootloader_message* out,
const Volume* v) {
wait_for_device(v->blk_device);
FILE* f = fopen(v->blk_device, "rb");
if (f == nullptr) {
LOGE("failed to open \"%s\": %s\n", v->blk_device, strerror(errno));
return -1;
}
bootloader_message temp;
int count = fread(&temp, sizeof(temp), 1, f);
if (count != 1) {
LOGE("failed to read \"%s\": %s\n", v->blk_device, strerror(errno));
return -1;
}
if (fclose(f) != 0) {
LOGE("failed to close \"%s\": %s\n", v->blk_device, strerror(errno));
return -1;
}
memcpy(out, &temp, sizeof(temp));
return 0;
}
static int set_bootloader_message_block(const bootloader_message* in,
const Volume* v) {
wait_for_device(v->blk_device);
unique_fd fd(open(v->blk_device, O_WRONLY | O_SYNC));
if (fd.get() == -1) {
LOGE("failed to open \"%s\": %s\n", v->blk_device, strerror(errno));
return -1;
}
size_t written = 0;
const uint8_t* start = reinterpret_cast<const uint8_t*>(in);
size_t total = sizeof(*in);
while (written < total) {
ssize_t wrote = TEMP_FAILURE_RETRY(write(fd.get(), start + written, total - written));
if (wrote == -1) {
LOGE("failed to write %" PRId64 " bytes: %s\n",
static_cast<off64_t>(written), strerror(errno));
return -1;
}
written += wrote;
}
if (fsync(fd.get()) == -1) {
LOGE("failed to fsync \"%s\": %s\n", v->blk_device, strerror(errno));
return -1;
}
return 0;
}
