Android Recovery模式与Recovery界面的中文详细说明
Android Recovery模式
来源: ChinaUnix博客日期:2009.04.25 22:58(共有条评论) 我要评论
Android
Recovery模式
(muddogxp 原创,转载请注明)
Recovery简介
Android利用Recovery模式,进行恢复出厂设置,OTA升级,patch升级及firmware升级。
升级一般通过运行升级包中的META-INF/com/google/android/update-script脚本来执行自定义升级,脚本中是一组recovery系统能识别的UI控制,文件系统操作命令,例如write_raw_image(写FLASH分区),copy_dir (复制目录)。该包一般被下载至SDCARD和CACHE分区下。如果对该包内容感兴趣,可以从
https://www.360docs.net/doc/3311156957.html,/showthread.php?t=442480下载JF升级包来看看。
升级中还涉及到包的数字签名,签名方式和普通JAR文件签名差不错。公钥会被硬编译入recovery,编译时生成在:out/target/product/XX/obj/PACKAGING/ota_keys_inc_intermediates/keys.inc
G1中的三种启动模式
MAGIC KEY:
?
camera +
power:bootloader模式,ADP里则可以使用fastboot模式
?
home + power:recovery模式
?
正常启动
Bootloader正常启动,又有三种方式,按照BCB(Bootloader Control Block, 下节介绍)中的command分类:
?
command == 'boot-recovery'
→启动recovery.img。recovery模式
?
command ==
'update-radio/hboot' →更新firmware(bootloader)
?
其他→启动boot.img
Recovery涉及到的其他系统及文件
CACHE分区文件
Recovery
工具通过NAND
cache分区上的三个文件和主系统打交道。主系统(包括恢复出厂设置和OTA升级)可以写入recovery所需的命令,读出recovery过程中的LOG和intent。
o/cache/recovery/command:
recovery命令,由主系统写入。所有命令如下:
?--send_intent=anystring
- write the text out to recovery.intent
?--update_package=root:path
- verify install an OTA package file
?--wipe_data
- erase user data (and cache), then reboot
?--wipe_cache
- wipe cache (but not user data), then reboot
o/cache/recovery/log:recovery过程日志,由主系统读出
o/cache/recovery/intent:recovery输出的intent
MISC分区内容
Bootloader Control Block
(BCB) 存放recovery
bootloader message。结构如下:
struct
bootloader_message {
char
command[32];
char
status[32]; // 未知用途
char
recovery[1024];
};
o
command可以有以下两个值
“boot-recovery”:标示recovery正在进行,或指示bootloader应该进入recovery
mode
“upd ate-hboot/radio”:指示bootloader更新firmware
o
recovery内容
“recovery\n
\n
”
其中recovery
command为CACHE:/recovery/command命令
两种Recovery
Case
FACTORY
RESET(恢复出厂设置)
?用户选择“恢复出厂设置”
?设置系统将"--wipe_data"命令写入/cache/recovery/command ?系统重启,并进入recover模式(/sbin/recovery)
?get_args()
将
"boot-recovery"和"--wipe_data"写入BCB
?erase_root()
格式化(擦除)DATA分区
?erase_root()
格式化(擦除)CACHE分区
?finish_recovery()
擦除BCB
?重启系统
?OTA
INSTALL(OTA升级)
?升级系统下载
OTA包到/cache/some-filename.zip
?升级系统写入recovery命令"--update_package=CACHE:some-filename.zip" ?重启,并进入recovery模式
?get_args()
将"boot-recovery"
和
"--update_package=..."
写入BCB
?install_package()
作升级
?finish_recovery()
擦除BCB
?**
如果安装包失败**
prompt_and_wait() 等待用户操作,选择ALT+S或ALT+W
升级或恢复出厂设置
?main()
调用
maybe_install_firmware_update()
?如果包里有hboot/radio的firmware则继续,否则返回
?将
"boot-recovery"
和"--wipe_cache"
写入BCB
?将
firmware image写入cache分区
?将
"update-radio/hboot"
和"--wipe_cache"
写入BCB
?重启系统
?bootloader自身更新firmware
?bootloader
将"boot-recovery"
写入BCB
?erase_root()
擦除CACHE分区
?清除
BCB
?main()
调用reboot()
重启系统
Recovery模式流程
/init
→init.rc →
/sbin/recovery →
main():recovery.c
?ui_init():ui.c
[UI initialize]
o gr_init():minui/graphics.c
[set tty0 to graphic
mode, open fb0]
o ev_init():minui/events.c
[open /dev/input/event*]
o res_create_surface:minui/resource.c
[create surfaces for all bitmaps used later, include icons, bmps]
o create
2 threads: progress/input_thread [create progress show and input
event handler thread]
get_args():recovery.c
o get_bootloader_message():bootloader.c
[read mtdblock0(misc partition) 2nd page for
commandline]
o check
if nand misc partition has boot message. If yes, fill argc/argv.
o If
no, get arguments from /cache/recovery/command, and fill argc/argv.
o set_bootloader_message():bootloader.c
[set bootloader message back to mtdblock0]
?Parser
argv[] filled above
?register_update_commands():commands.c
[ register all commands with name and hook function ]
o registerCommand():commands.c
?Register
command with name, hook, type, cookie.
?Commands,
e.g: assert, delete, copy_dir, symlink, write_raw_image.
o registerFunction():commands.c
?Register
function with name, hook, cookie.
?Function,
e.g: get_mark, matches, getprop, file_contains
?
?install_package():
o translate_root_path():roots.c
[ "SYSTEM:lib" and turns it into a string like
"/system/lib", translate the updater.zip path ]
o mzOpenZipArchive():zip.c
[ open updater.zip file (uncompass) ]
o handle_update_package():install.c
?verify_jar_signature():verifier.c
[ verify signature with keys.inc key; verify manifest and zip
package archive ]
?verifySignature()
[ verify the signature file: CERT.sf/rsa. ]
?digestEntry():verifier.c
[ get SHA-1 digest of CERT.sf
file ]
?RSA_verify(public
key:keys.inc,
signature:CERT.rsa, CERT.sf's digest):libc/rsa.c
[ Verify a 2048 bit RSA PKCS1.5 signature against an expected
SHA-1 hash. Use public key to decrypt the CERT.rsa to get
original SHA digest, then compare to digest of CERT.sf ]
?verifyManifest()
[ Get manifest SHA1-Digest from CERT.sf. Then do digest to
MANIFEST.MF. Compare them ]
?verifyArchive()
[ verify all the files in update.zip with digest listed in
MANIFEST.MF ]
?find_update_script():install.c
[ find META-INF/com/google/android/update-script updater script ]
?handle_update_script():install.c
[ read cmds from script file, and do parser, exec ]
?parseAmendScript():amend.c
[ call yyparse() to parse to command ]
?exeCommandList():install.c
?exeCommand():execute.c
[ call command hook function ]
?
o
?
?erase
DATA/CACHE partition
?prompt_and_wait():recovery.c
[ wait for user input: 1) reboot 2) update.zip 3) wipe data ]
o ui_key_xxx
get ALT+x keys
o1)
do nothing
o2)
install_package('SDCARD:update.zip')
o3)
erase_root() →
format_root_device() DATA/CACHE
?may_install_firmware_update():firmware.c
[ remember_firmware_update() is called by write_hboot/radio_image
command, it stores the bootloader image to CACHE partition, and
write update-hboot/radio command to MISC partition for bootloader
message to let bootloader update itself after reboot ]
o set_bootloader_message()
o write_update_for_bootloader():bootloader.c
[ write firmware image into CACHE partition with update_header,
busyimage and failimage ]
?finish_recovery():recovery.c
[ clear the recovery command and prepare to boot a (hopefully
working) system, copy our log file to cache as well (for the system
to read), and record any intent we were asked to communicate back to
the system. ]
?reboot()
Recovery模式流程图
以下流程图绘制了系统从启动加载bootloader后的行为流程。
Recovery界面的中文详细说明
Recovery界面的中文详细说明
首先,介绍下进入Recovery的方式
1:完全关机,按住音量下+电源键开机,进入bootloader界面2:按音量键移动光标到Recovery那一行
3:按电源键(之后机器会重启进入Recovery)
音量键为光标选择键,可以用来移动光标,电源键为确认键!一:Recovery主界面
*reboot system now:重启手机(刷机完毕选择此项就能重新启动系统)
*apply SDcard:update.zip:安装存储卡中的update.zip升级包(你可以把刷机包命名为update.zip然后用这个选项直接升级)
*wipe data/factory reset:清除用户数据并恢复出厂设置(刷机前必须执行的选项)
*wipe cache partition:清除系统缓存(刷机前执行)(系统出问题也可尝试此选项,一般能够解决)
*install zip from SDcard:从SDcard上安装zip升级包(可以执行任意名称的zip升级包,不限制升级包名称)
*backup and restore:备份和还原系统(作用和原理如同电脑上的chost一键备份和还原)*mounts and storage:挂载和存储选项(详细功能见下面的解释)
*advanced:高级设置
二:backup and restore功能详解
*Backup:备份当前系统
*Restore:还原上一个系统
*Advanced Restore:高级还原选项(用户可以自选之前备份的系统,然后进行恢复)
三:mounts and storage功能详解
*mount /system:挂载system文件夹(基本用不到)
*mount /data:挂载data文件夹(基本用不到)
*unmount /cache:取消cache文件夹挂载(基本用不到)
*unmount /sdcard:取消内存卡挂载(基本用不到)
*mount /sd-ext:挂载内存卡Ext分区(基本用不到)
*format boot:格式化boot(刷机前最好执行一下)
*format system:格式化system(刷机前最好执行一下)
*format data:格式化data(刷机前最好执行一下)
*format cache:格式化cache(刷机前最好执行一下)
*format sdcard:格式化内储卡(执行此项你会后悔的)
*format sd-ext:格式化内存卡Ext分区(执行此项你会后悔的)
*mount USB storage:开启Recovery模式下的USB大容量存储功能(也就是说可以在