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Frida CLI tools

CLI tools for Frida.

Making dev changes to frida-tools

You do not need to build this repo in order to make changes (for a pull request, or for local development).

Simply set your PYTHONPATH environment variable to wherever you've cloned this repo to.

For example, on Windows, assuming you clone to C:\src:

git clone https://github.com/frida/frida-tools.git
cd frida-tools
SET PYTHONPATH=C:\src\frida-tools

Now when you run frida.exe, these scripts and any changes you make will be referenced instead!

Loading your custom frida-java-bridge

Add the following lines to agents/tracer/agent.ts:

Object.defineProperty(global, 'Java', { value: require('frida-java-bridge') });

Run live reload:

cd agents/tracer; npm link frida-java-bridge; npm run watch

Now you can:

  1. make changes to agents/tracer/node_modules/frida-java-bridge/*
  2. run your frida-tools from this repo and see how it works!

Installing Fish completions

Currently there is no mechanism to install Fish completions through the setup.py script so if you want to have completions in Fish you will have to install it manually. Unless you've changed your XDG_CONFIG_HOME location, you should just copy the completion file into ~/.config/fish/completions like so:

cp completions/frida.fish ~/.config/fish/completions

frida-itrace file format

File starts with a 4-byte magic: "ITRC"

frida-tools/frida_tools/itracer.py

Lines 365 to 366 in 1ea077f

self._outfile = open(outpath, "wb")
self._outfile.write(self.FILE_MAGIC)

Then, following that, there are two different types of records, MESSAGE and CHUNK. Each record starts with a big-endian uint32 specifying the type of record, where 1 means MESSAGE, 2 means CHUNK.

MESSAGE

  • length: uint32 (big-endian)
  • message: JSON, UTF-8 encoded
  • data_size: uint32 (big-endian)
  • data_values: uint8[data_size]

Generated here.

There are three different kinds of MESSAGEs:

  • "itrace:start": Signals that the trace is starting, providing the initial register values. Contains register names and sizes in the JSON portion, and register values in the data portion. Generated here.

  • "itrace:end": Signals that the endpoint was reached, when specifying a range with an end address included.

  • "itrace:compile": Signals that a basic block was discovered, providing the schema of future CHUNKs pertaining to it. Generated here and by the code above it that computes the "writes" array.

    The "writes" array contains tuples (arrays) that look like this:

    (block_offset, cpu_ctx_offset)

    Where block_offset is how many bytes into the basic block the write happens, and cpu_ctx_offset is the index into the registers declared by "itrace:start".

CHUNK

  • size: uint32 (big-endian)
  • data: uint8[size]

Generated here.

The CHUNK records combine to a stream of raw register values at different parts of the given basic block. Each record looks like this:

  • block_start_address: uint64 (target-endian, i.e. little-endian on arm64)
  • link_register_value: uint64 (target-endian)
  • block_register_values: uint64[n], where n depends on the specific basic block. (See above docs on "itrace:compile" and its "writes" array.)