From 2fe7889912c9bb340f302a037585b7b1836ac94f Mon Sep 17 00:00:00 2001 From: Andrea Fioraldi Date: Mon, 3 Feb 2020 13:11:10 +0100 Subject: move custom and pythoon mutators examples into examples/ --- examples/python_mutators/simple-chunk-replace.py | 59 ++++++++++++++++++++++++ 1 file changed, 59 insertions(+) create mode 100644 examples/python_mutators/simple-chunk-replace.py (limited to 'examples/python_mutators/simple-chunk-replace.py') diff --git a/examples/python_mutators/simple-chunk-replace.py b/examples/python_mutators/simple-chunk-replace.py new file mode 100644 index 00000000..218dd4f8 --- /dev/null +++ b/examples/python_mutators/simple-chunk-replace.py @@ -0,0 +1,59 @@ +#!/usr/bin/env python +# encoding: utf-8 +''' +Simple Chunk Cross-Over Replacement Module for AFLFuzz + +@author: Christian Holler (:decoder) + +@license: + +This Source Code Form is subject to the terms of the Mozilla Public +License, v. 2.0. If a copy of the MPL was not distributed with this +file, You can obtain one at http://mozilla.org/MPL/2.0/. + +@contact: choller@mozilla.com +''' + +import random + +def init(seed): + ''' + Called once when AFLFuzz starts up. Used to seed our RNG. + + @type seed: int + @param seed: A 32-bit random value + ''' + # Seed our RNG + random.seed(seed) + return 0 + +def fuzz(buf, add_buf): + ''' + Called per fuzzing iteration. + + @type buf: bytearray + @param buf: The buffer that should be mutated. + + @type add_buf: bytearray + @param add_buf: A second buffer that can be used as mutation source. + + @rtype: bytearray + @return: A new bytearray containing the mutated data + ''' + # Make a copy of our input buffer for returning + ret = bytearray(buf) + + # Take a random fragment length between 2 and 32 (or less if add_buf is shorter) + fragment_len = random.randint(1, min(len(add_buf), 32)) + + # Determine a random source index where to take the data chunk from + rand_src_idx = random.randint(0, len(add_buf) - fragment_len) + + # Determine a random destination index where to put the data chunk + rand_dst_idx = random.randint(0, len(buf)) + + # Make the chunk replacement + ret[rand_dst_idx:rand_dst_idx + fragment_len] = add_buf[rand_src_idx:rand_src_idx + fragment_len] + + # Return data + return ret -- cgit 1.4.1