Awesome

frida-stack

Small frida module for ensuring you get the stack information you wanted.

What?

Often when using Frida, I would run into issues with wanting specific stack traces. Then I realized I didn't have a specific context window, or the stack traces didn't contain the correct shared libraries in them. This resulted in me re-writing the same functions all the time.

In other instances, mostly when reverse engineering heavily obfuscated or packed code, I would have discovered functions or places in memory which had been created without any exports available. This would lead to questions like, what process/library owned this? Where am I inside those libraries?

To answer the above questions, I wrapped some of the standard Thread.Backtrace functions and added some scanning of the Process memory ranges.

Installing

$ npm install frida-extended-stack

Usage

import { Stack } from 'frida-stack'

function hook_exit() {
  const _exitPtr = Module.findExportByName('libc.so', '_exit');

  if (_exitPtr) {
    const _exit = new NativeFunction(_exitPtr, 'int', ['int']);

    Interceptor.replace(
      _exitPtr,
      new NativeCallback(
        function (status) {
          console.log(`[+] _exit : ${status} from ${Stack.getModuleInfo(this.context.pc)}`);
	        console.log(Stack.native(this.context)
          return _exit(status);
        },
        'int',
        ['int'],
      ),
    );
  }
}

Output:

[Pixel 4::com.example.package ]-> [+] _exit : 0 from 0x7713d25000 libexamplesharedlib.so:0x1aae8
0x7713d25000 libexamplesharedlib.so:0x1aae8

Now you have a library and the exact offset into the library for reversing.

License

Copyright 2020-2024 Tim 'diff' Strazzere <diff@protonmail.com>

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.