PAPIMonitor (Python API Monitor for Android apps) is a python tool based on Frida for monitoring user-select APIs during the app execution. The app should be installed within an emulator already connected through ADB to the pc host. The user can choose to monitor a predefined list of APIs divided into several categories (e.g., Device Data, Device Info, SMS) or a custom list of APIs passed through the command line to the script. The tool stores the invoked API, the parameters, the return value, and the line and file from where it was called.

Below is an example of output:

{   
    "category": "Custom", 
    "class": "com.dave.popupre.MainActivity", 
    "method": "getText", 
    "args": [], 
    "calledFrom": "com.dave.popupre.MainActivity$1.onClick(MainActivity.java:26)", 
    "returnValue": "Hello Toast!", 
    "time": "03/09/2021, 14:43:06"
}

Warning with Google Emulator

Frida seems broken on Android 11-12 (x86_64) (Google Emulatore).

• issue-1917
• issue-1977
• issue-1982

Installation

General requirements:

sudo apt-get install libjpeg-dev zlib1g-dev

Installation with pyenv and virtualenv

• Install pyenv and pyenv-virtualenv

pyenv install 3.8.0
pyenv virtualenv 3.8.0 papi-monitor
pyenv activate 3.8.0/envs/papi-monitor
pip3 install -r requirements

Installation with virtualenv

• install virtualenv

sudo apt-get install python3-virtualenv

• activate virtualenv

virtualenv env
source env/bin/activate

• install requirements

pip install -r requirements

Post Installation

• adb in path file
• emulator/device already running and connect

Usage

Predefined Categories

• Device Data
• Device Info
• SMS
• System Manager
• Base64 encode/decode
• Dex Class Loader
• Network
• Crypto
• Crypto - Hash
• Binder
• IPC
• Database
• SharedPreferences
• WebView
• Java Native Interface
• Command
• Process
• FileSytem - Java

Frida Script

A lot of Frida Script for Android can be found here.