diff options
Diffstat (limited to 'bootloader.cpp')
-rw-r--r-- | bootloader.cpp | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/bootloader.cpp b/bootloader.cpp new file mode 100644 index 000000000..f6c0e9341 --- /dev/null +++ b/bootloader.cpp @@ -0,0 +1,235 @@ +/* + * 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 <android-base/file.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 bool read_misc_partition(const Volume* v, size_t offset, size_t size, std::string* out); +static bool write_misc_partition(const Volume* v, size_t offset, const std::string& in); + +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) { + std::string s; + if (!read_misc_partition(v, BOOTLOADER_MESSAGE_OFFSET_IN_MISC, sizeof(bootloader_message), + &s)) { + return -1; + } + memcpy(out, s.data(), s.size()); + return 0; + } + LOGE("Unknown misc partition fs_type \"%s\"\n", v->fs_type); + return -1; +} + +bool read_wipe_package(size_t size, std::string* out) { + Volume* v = volume_for_path("/misc"); + if (v == nullptr) { + LOGE("Cannot load volume /misc!\n"); + return false; + } + if (strcmp(v->fs_type, "mtd") == 0) { + LOGE("Read wipe package on mtd is not supported.\n"); + return false; + } else if (strcmp(v->fs_type, "emmc") == 0) { + return read_misc_partition(v, WIPE_PACKAGE_OFFSET_IN_MISC, size, out); + } + LOGE("Unknown misc partition fs_type \"%s\"\n", v->fs_type); + return false; +} + +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) { + std::string s(reinterpret_cast<const char*>(in), sizeof(*in)); + bool success = write_misc_partition(v, BOOTLOADER_MESSAGE_OFFSET_IN_MISC, s); + return success ? 0 : -1; + } + 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 bool read_misc_partition(const Volume* v, size_t offset, size_t size, std::string* out) { + wait_for_device(v->blk_device); + unique_fd fd(open(v->blk_device, O_RDONLY)); + if (fd.get() == -1) { + LOGE("Failed to open \"%s\": %s\n", v->blk_device, strerror(errno)); + return false; + } + if (lseek(fd.get(), static_cast<off_t>(offset), SEEK_SET) != static_cast<off_t>(offset)) { + LOGE("Failed to lseek \"%s\": %s\n", v->blk_device, strerror(errno)); + return false; + } + out->resize(size); + if (!android::base::ReadFully(fd.get(), &(*out)[0], size)) { + LOGE("Failed to read \"%s\": %s\n", v->blk_device, strerror(errno)); + return false; + } + return true; +} + +static bool write_misc_partition(const Volume* v, size_t offset, const std::string& in) { + 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 false; + } + if (lseek(fd.get(), static_cast<off_t>(offset), SEEK_SET) != static_cast<off_t>(offset)) { + LOGE("Failed to lseek \"%s\": %s\n", v->blk_device, strerror(errno)); + return false; + } + if (!android::base::WriteFully(fd.get(), in.data(), in.size())) { + LOGE("Failed to write \"%s\": %s\n", v->blk_device, strerror(errno)); + return false; + } + + if (fsync(fd.get()) == -1) { + LOGE("Failed to fsync \"%s\": %s\n", v->blk_device, strerror(errno)); + return false; + } + return true; +} |