Android documentation decompile

Made by Li Wendong rayleeya@gmail.com 

2010-12-13 Monday in Beijing 

A, decompile flowchart 

 

Second, tools to use (command)

Preparations 

Suppose I am working directory for the $ AndroidDecompile, first of all to system.img in (or compiled from source code) of several important odex files are copied to the working directory, they are: core.odex, ext.odex, framework . odex, android.policy.odex, services.odex (also can be placed in another directory, by setting BOOTCLASSPATH specified, the default is the current directory, please refer to baksmali on BOOTCLASSPATH help information.) 

Download the following tools to $ AndroidDecompile in: 

Baksmali: 

http://code.google.com/p/smali/downloads/list 

Smali: 

http://code.google.com/p/smali/downloads/list 

Dex2jar: 

http://code.google.com/p/dex2jar/downloads/list 

JD-GUI (Java Decompile GUI): 

http://java.decompiler.free.fr/?q=jdgui <!--[ if! supportNestedAnchors ]--><!--[ endif] -> 

AutoSign: 

http://d.download.csdn.net/down/2768910/fjfdszj 

Apktool 

http://code.google.com/p/android-apktool/downloads/list 

Suppose we have an application, compile the class file after it took out alone, that there are two files app.apk and app.odex, place them on the next $ AndroidDecompile. 

1. Odex file using baksmali.jar the document is divided into smali 

$ Java-jar baksmali-1.2.5.jar-x app.odex 

If successful, will generate a $ AndroidDecompile out directory, which are to ". Smali" for the file name suffix, in this role does not go into these files. 

2. Use smali.jar the out / directory smali files into classes.dex 

$ Java-Xmx512M-jar smali-1.2.5.jar out-o classes.dex 

classes.dex Dalvik VM is used in the compiled class file format, in the normal apk file will have. 

3. Use dex2jar classes.dex decompiled the jar file 

After the download dex2jar compressed codecs, which will have dex2jar.sh (and dex2jar.bat) files, documents and dex2jar.sh if classes.dex in the same directory, use the following ways classes.dex decompiled jar File: 

$ Dex2jar.sh classes.dex 

If successful, it will generate in the current directory, compiled files anti-classes.dex.dex2jar.jar. 

dex2jar dex files that can be manipulated, you can directly manipulate apk file, it uses rules: 

dex2jar file1.dexORapk file2.dexORapk ... 

4. Using the JD-GUI view the anti-compiled jar file 

JD-GUI is a visual Java decompiler code viewer, it can be real-time anti-compiled java class file to view the file. Jd-gui extract the downloaded file, perform directory jd-gui executable file to start and then load the previous step in the anti-compiled classes.dex.dex2jar.jar files. 

5. From odex classes.dex anti-compiled files and other resources re-packaged into a complete apk 

We assume that the above situation is the application compiled class files from apk file is stripped out, here is how to do the steps above to get the classes.dex and apk file in other re-packaged into a usable apk. 

First, the anti-compiled classes.dex and original app.apk (excluding classes.dex) re-compressed into a complete app.apk (apk file compression tools available to open), into the app that will classes.dex . apk in. 

Unzip the downloaded file AutoSign, you can see signapk.jar (there are a Sign.bat) file, execute the following command to app.apk file signature, to generate a working apk file. 

$ Java-jar signapk.jar testkey.x509.pem testkey.pk8 app.apk app_signed.apk 

6. Apktool use 

There is a tool the Internet is apktool, apk can be resolved, de-compile the resource file, and parse the class file into smali documents; while the files can be parsed into a re-packaged apk. Several features and tools described above is similar to its use as follows: 

apktool d app.apk and decompile app.apk to the folder and 

apktool b app from the app folder, re-APK, output to ABC \ dist \ out.apk 

The specific use will not go, please refer to the official website, or: 

http://www.geeka.net/2010/05/apktool-decode-android-google-code/ 

7. My $ AndroidDecompile screenshot files directory 

 

Third, a number of tools to help information 

1. Baksmali help information 

usage: java-jar baksmali.jar [options] <dex-file> 

disassembles and / or dumps a dex file 

-?,-- Help Prints the help message then exits. 

-B, - no-debug-info Specify twice for debug options 

don't write out debug info (. local, 

. Param,. Line, etc.) 

-C, - bootclasspath <BOOTCLASSPATH> The bootclasspath jars to use, for 

analysis. Defaults to 

core.jar: ext.jar: framework.jar: andro 

id.policy.jar: services.jar. If the 

value begins with a:, it will be 

appended to the default 

bootclasspath instead of replacing it 

-D, - bootclasspath-dir <DIR> The base folder to look for the 

bootclasspath files in. Defaults to 

the current directory 

-F, - code-offsets Add comments to the disassembly 

containing the code offset for each address 

-L, - use-locals Output the. Locals directive with 

the number of non-parameter 

registers, rather than the. register 

-O, - output <DIR> Directive with the total number of register 

the directory where the disassembled 

files will be placed. The default is out 

-P, - no-parameter-registers Use the v <n> syntax instead of the 

p <n> syntax for registers mapped to 

method parameters 

-R, - register-info <REGISTER_INFO_TYPES> Print the specificed type (s) of 

register information for each 

instruction. "ARGS, DEST" is the 

default if no types are specified. 

Valid values are: 

ALL: all pre-and post-instruction registers. 

ALLPRE: all pre-instruction registers 

ALLPOST: all post-instruction registers 

ARGS: any pre-instruction registers 

used as arguments to the instruction 

DEST: the post-instruction 

destination register, if any 

MERGE: Any pre-instruction register 

has been merged from more than 1 

different post-instruction register 

from its predecessors 

FULLMERGE: For each register that 

would be printed by MERGE, also show 

the incoming register types that 

were merged 

-S, - sequential-labels Create label names using a 

sequential numbering scheme per 

label type, rather than using the 

bytecode address 

-V, - version Prints the version then exits 

-X, - deodex Deodex the given odex file. This 

option is ignored if the input file 

is not an odex file 

2. Smali help information 

usage: java-jar smali.jar [options] [-] [<smali-file> | folder] * 

assembles a set of smali files into a dex file 

-?,-- Help prints the help message then exits. Specify twice for 

debug options 

-O, - output <FILE> the name of the dex file that will be written. The default 

is out.dex 

-V, - version prints the version then exits 

3. Auto-sign with the help of information 

SignApk.jar is a tool included with the Android platform source bundle. 

testkey.pk8 is the private key that is compatible with the recovery image included in this zip file 

testkey.x509.pem is the corresponding certificate / public key 

Usage: 

java-jar signapk.jar testkey.x509.pem testkey.pk8 update.zip update_signed.zip 

4. Apktool help information 

Apktool v1.3.2 - a tool for reengineering Android apk files 

Copyright 2010 Ryszard Wi? Niewski <brut.alll@gmail.com> 

Apache License 2.0 (http://www.apache.org/licenses/LICENSE-2.0) 

Usage: apktool [-v | - verbose] COMMAND [...] 

COMMANDs are: 

d [ecode] [OPTS] <file.apk> [<dir>] 

Decode <file.apk> to <dir>. 

OPTS: 

-S, - no-src 

Do not decode sources. 

-R, - no-res 

Do not decode resources. 

-D, - debug 

Decode in debug mode. Check project page for more info. 

-F, - force 

Force delete destination directory. 

-T <tag>, - frame-tag <tag> 

Try to use framework files tagged by <tag>. 

- Keep-broken-res 

Use if there was an error and some resources were dropped, eg: 

"Invalid config flags detected. Dropping resources", but you 

want to decode them anyway, even with errors. You will have to 

fix them manually before building. 

b [uild] [OPTS] [<app_path>] [<out_file>] 

Build an apk from already decoded application located in <app_path>. 

It will automatically detect, whether files was changed and perform 

needed steps only. 

If you omit <app_path> then current directory will be used. 

If you omit <out_file> then <app_path> / dist / <name_of_original.apk> 

will be used. 

OPTS: 

-F, - force-all 

Skip changes detection and build all files. 

-D, - debug 

Build in debug mode. Check project page for more info. 

if | install-framework <framework.apk> [<tag>] 

Install framework file to your system. 

Additional info for, See: http://code.google.com/p/android-apktool/ 

IV References 

1. Smali 

http://code.google.com/p/smali/ 

http://www.geeka.net/2010/05/android-apk-odex-classes-dex/ 

2. ApkTool 

http://code.google.com/p/android-apktool/ 

http://www.geeka.net/2010/05/apktool-decode-android-google-code/