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| -rw-r--r-- | include/android_bootloader_message.h | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/include/android_bootloader_message.h b/include/android_bootloader_message.h new file mode 100644 index 00000000000..b84789f0222 --- /dev/null +++ b/include/android_bootloader_message.h @@ -0,0 +1,246 @@ +/* + * This is from the Android Project, + * Repository: https://android.googlesource.com/platform/bootable/recovery + * File: bootloader_message/include/bootloader_message/bootloader_message.h + * Commit: c784ce50e8c10eaf70e1f97e24e8324aef45faf5 + * + * Copyright (C) 2008 The Android Open Source Project + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#ifndef __ANDROID_BOOTLOADER_MESSAGE_H +#define __ANDROID_BOOTLOADER_MESSAGE_H + +/* compiler.h defines the types that otherwise are included from stdint.h and + * stddef.h + */ +#include <compiler.h> + +/* Spaces used by misc partition are as below: + * 0 - 2K For bootloader_message + * 2K - 16K Used by Vendor's bootloader (the 2K - 4K range may be optionally used + * as bootloader_message_ab struct) + * 16K - 64K Used by uncrypt and recovery to store wipe_package for A/B devices + * Note that these offsets are admitted by bootloader,recovery and uncrypt, so they + * are not configurable without changing all of them. */ +static const size_t BOOTLOADER_MESSAGE_OFFSET_IN_MISC = 0; +static const size_t WIPE_PACKAGE_OFFSET_IN_MISC = 16 * 1024; + +/* Bootloader Message (2-KiB) + * + * This structure describes the content of a block in flash + * that is used for recovery and the bootloader to talk to + * each other. + * + * The command field is updated by linux when it wants to + * reboot into recovery or to update radio or bootloader firmware. + * It is also updated by the bootloader when firmware update + * is complete (to boot into recovery for any final cleanup) + * + * The status field was used by the bootloader after the completion + * of an "update-radio" or "update-hboot" command, which has been + * deprecated since Froyo. + * + * The recovery field is only written by linux and used + * for the system to send a message to recovery or the + * other way around. + * + * The stage field is written by packages which restart themselves + * multiple times, so that the UI can reflect which invocation of the + * package it is. If the value is of the format "#/#" (eg, "1/3"), + * the UI will add a simple indicator of that status. + * + * We used to have slot_suffix field for A/B boot control metadata in + * this struct, which gets unintentionally cleared by recovery or + * uncrypt. Move it into struct bootloader_message_ab to avoid the + * issue. + */ +struct bootloader_message { + char command[32]; + char status[32]; + char recovery[768]; + + /* The 'recovery' field used to be 1024 bytes. It has only ever + * been used to store the recovery command line, so 768 bytes + * should be plenty. We carve off the last 256 bytes to store the + * stage string (for multistage packages) and possible future + * expansion. */ + char stage[32]; + + /* The 'reserved' field used to be 224 bytes when it was initially + * carved off from the 1024-byte recovery field. Bump it up to + * 1184-byte so that the entire bootloader_message struct rounds up + * to 2048-byte. */ + char reserved[1184]; +}; + +/** + * We must be cautious when changing the bootloader_message struct size, + * because A/B-specific fields may end up with different offsets. + */ +#if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus) +static_assert(sizeof(struct bootloader_message) == 2048, + "struct bootloader_message size changes, which may break A/B devices"); +#endif + +/** + * The A/B-specific bootloader message structure (4-KiB). + * + * We separate A/B boot control metadata from the regular bootloader + * message struct and keep it here. Everything that's A/B-specific + * stays after struct bootloader_message, which should be managed by + * the A/B-bootloader or boot control HAL. + * + * The slot_suffix field is used for A/B implementations where the + * bootloader does not set the androidboot.ro.boot.slot_suffix kernel + * commandline parameter. This is used by fs_mgr to mount /system and + * other partitions with the slotselect flag set in fstab. A/B + * implementations are free to use all 32 bytes and may store private + * data past the first NUL-byte in this field. It is encouraged, but + * not mandatory, to use 'struct bootloader_control' described below. + * + * The update_channel field is used to store the Omaha update channel + * if update_engine is compiled with Omaha support. + */ +struct bootloader_message_ab { + struct bootloader_message message; + char slot_suffix[32]; + char update_channel[128]; + + /* Round up the entire struct to 4096-byte. */ + char reserved[1888]; +}; + +/** + * Be cautious about the struct size change, in case we put anything post + * bootloader_message_ab struct (b/29159185). + */ +#if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus) +static_assert(sizeof(struct bootloader_message_ab) == 4096, + "struct bootloader_message_ab size changes"); +#endif + +#define BOOT_CTRL_MAGIC 0x42414342 /* Bootloader Control AB */ +#define BOOT_CTRL_VERSION 1 + +struct slot_metadata { + /* Slot priority with 15 meaning highest priority, 1 lowest + * priority and 0 the slot is unbootable. */ + uint8_t priority : 4; + /* Number of times left attempting to boot this slot. */ + uint8_t tries_remaining : 3; + /* 1 if this slot has booted successfully, 0 otherwise. */ + uint8_t successful_boot : 1; + /* 1 if this slot is corrupted from a dm-verity corruption, 0 + * otherwise. */ + uint8_t verity_corrupted : 1; + /* Reserved for further use. */ + uint8_t reserved : 7; +} __attribute__((packed)); + +/* Bootloader Control AB + * + * This struct can be used to manage A/B metadata. It is designed to + * be put in the 'slot_suffix' field of the 'bootloader_message' + * structure described above. It is encouraged to use the + * 'bootloader_control' structure to store the A/B metadata, but not + * mandatory. + */ +struct bootloader_control { + /* NUL terminated active slot suffix. */ + char slot_suffix[4]; + /* Bootloader Control AB magic number (see BOOT_CTRL_MAGIC). */ + uint32_t magic; + /* Version of struct being used (see BOOT_CTRL_VERSION). */ + uint8_t version; + /* Number of slots being managed. */ + uint8_t nb_slot : 3; + /* Number of times left attempting to boot recovery. */ + uint8_t recovery_tries_remaining : 3; + /* Ensure 4-bytes alignment for slot_info field. */ + uint8_t reserved0[2]; + /* Per-slot information. Up to 4 slots. */ + struct slot_metadata slot_info[4]; + /* Reserved for further use. */ + uint8_t reserved1[8]; + /* CRC32 of all 28 bytes preceding this field (little endian + * format). */ + uint32_t crc32_le; +} __attribute__((packed)); + +#if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus) +static_assert(sizeof(struct bootloader_control) == + sizeof(((struct bootloader_message_ab *)0)->slot_suffix), + "struct bootloader_control has wrong size"); +#endif + +#ifndef __UBOOT__ + +#ifdef __cplusplus + +#include <string> +#include <vector> + +/* Return the block device name for the bootloader message partition and waits + * for the device for up to 10 seconds. In case of error returns the empty + * string. */ +std::string get_bootloader_message_blk_device(std::string* err); + +/* Read bootloader message into boot. Error message will be set in err. */ +bool read_bootloader_message(bootloader_message* boot, std::string* err); + +/* Read bootloader message from the specified misc device into boot. */ +bool read_bootloader_message_from(bootloader_message* boot, const std::string& misc_blk_device, + std::string* err); + +/* Write bootloader message to BCB. */ +bool write_bootloader_message(const bootloader_message& boot, std::string* err); + +/* Write bootloader message to the specified BCB device. */ +bool write_bootloader_message_to(const bootloader_message& boot, + const std::string& misc_blk_device, std::string* err); + +/* Write bootloader message (boots into recovery with the options) to BCB. Will + * set the command and recovery fields, and reset the rest. */ +bool write_bootloader_message(const std::vector<std::string>& options, std::string* err); + +/* Write bootloader message (boots into recovery with the options) to the specific BCB device. Will + * set the command and recovery fields, and reset the rest. */ +bool write_bootloader_message_to(const std::vector<std::string>& options, + const std::string& misc_blk_device, std::string* err); + +/* Update bootloader message (boots into recovery with the options) to BCB. Will + * only update the command and recovery fields. */ +bool update_bootloader_message(const std::vector<std::string>& options, std::string* err); + +/* Update bootloader message (boots into recovery with the |options|) in |boot|. Will only update + * the command and recovery fields. */ +bool update_bootloader_message_in_struct(bootloader_message* boot, + const std::vector<std::string>& options); + +/* Clear BCB. */ +bool clear_bootloader_message(std::string* err); + +/* Writes the reboot-bootloader reboot reason to the bootloader_message. */ +bool write_reboot_bootloader(std::string* err); + +/* Read the wipe package from BCB (from offset WIPE_PACKAGE_OFFSET_IN_MISC). */ +bool read_wipe_package(std::string* package_data, size_t size, std::string* err); + +/* Write the wipe package into BCB (to offset WIPE_PACKAGE_OFFSET_IN_MISC). */ +bool write_wipe_package(const std::string& package_data, std::string* err); + +#else + +#include <stdbool.h> + +/* C Interface. */ +bool write_bootloader_message(const char* options); +bool write_reboot_bootloader(void); + +#endif /* ifdef __cplusplus */ + +#endif /* __UBOOT__ */ + +#endif /* __ANDROID_BOOTLOADER_MESSAGE_H */ |