jzqCode / Jiagu

Android apk jiagu

中文文档

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APK reinforcement

• Support Android 5.0 and above (tested on 5.1, 7.1, 8.1, 10.0, 11.0 real machines)
• Support multi-dex reinforcement
• Adopt no-landing loading dex scheme

I. Module description

Tool development debugging use

• app: the source code for test
• jiagu: used to generate shell dex
• pack: java executable for packaging the hardened app

Release tools

• JigguTool: package of hardening tools, if you only need to use the hardening function, you can directly use the tools in this directory

II. Script description

Tool development debugging use

• Jiagu_app.bat: compile and package the app, the packaged application is used for hardening test
• Jiagu_build.bat: compile and generate hardening tools
• Jiagu_input.bat: harden the apk under input directory

Release tool

• Jiagu_update.bat: update the tools compiled by Jiagu_build to the JiaguTool directory

III. Instructions for use

Method 1 (tool development and debugging use).

• 1. Execute the script Jiagu_build.bat to generate the hardening tool
• 2. Put the application to be reinforced into the input folder, execute the script Jiagu_input.bat to reinforce it, and the reinforced application will be exported to the output folder.

Method 2 (Release tool).

• The hardening environment will be packaged to JiaguTool, you can use jiaguTool to harden the application directly
• If you modify the code of the reinforcement tool, you can execute Jiagu_updata.bat to repackage the reinforcement tool

IV. Hardening principle

1. Hardening tool processing

• Get the application name of the app
• Modify the application of the app's AndroidManifest.xml to the dex shell application
• Shell dex and source dex are spliced into one dex in the following format.
  • shell dex + (1 byte application name length + app's application name + 4 bytes source dex size + source dex) + 4 bytes source dex2 size + [source dex2] + 4 bytes source dex3 size + [source dex3] + ... + 4-byte shell dex size
  • AES encryption for the first 512 bytes of data in parentheses
  • dex header for data in middle brackets (i.e., first 112 bits for iso-or)
• Packaged signed app

2. Shell dex processing

• decrypt the application name and dex of the app
• Load the app's dex
  • Android8.0 below use call libart's OpenMemory function to load dex in memory
  • Android8.0 and above use the InMemoryDexClassLoader provided by the system to load the dex in memory
• replace shell application with application of app