Code repository for "Retrowrite: Statically Instrumenting COTS Binaries for Fuzzing and Sanitization" (in IEEE S&P'20). Please refer to the paper for technical details. There's also a 36c3 presentation and 36c3 video to get you started.
Retrowrite ships with two utilities to support binary rewriting:
- rwtools.asan.asantool: Instrument binary with binary-only Address Sanitizer (BASan).
- librw.rw : Generate symbolized assembly files from binaries
This section highlights the steps to get you up to speed to use retrowrite for rewriting PIC binaries.
Retrowrite is implemented in python3 (3.6). Make sure python3 and python3-venv is installed on system. Retrowrite depends on capstone. The capstone shipped with distribution is not compatible with this version. The setup script pulls the latest version of capstone from the repository and builds it. Make sure that your system meets the requirements to build capstone.
Run setup.sh:
./setup.sh
Activate the virtualenv (from root of the repository):
source retro/bin/activate
(Bonus) To exit virtualenv when you're done with retrowrite:
deactivate
The target binary
- must be compiled as position independent code (PIC/PIE)
- must be x86_64 (32 bit at your own risk)
- must contain symbols (i.e., not stripped; if stripped, please recover symbols first)
- must not contain C++ exceptions (i.e., C++ exception tables are not recovered and simply stripped during lifting)
The individual tools also have commandline help which describes all the
options, and may be accessed with -h. The below steps should quickly get you
started with using retrowrite.
python3 -m rwtools.asan.asantool </path/to/binary/> </path/to/output/binary>
Note: Make sure that the binary is position-independent and is not stripped.
This can be checked using file command (the output should say ELF shared object).
Example, create an instrumented version of /bin/ls:
python3 -m rwtools.asan.asantool /bin/ls ls-basan-instrumented
This will generate an assembly (.s) file that can be assembled and linked
using any compiler, example:
gcc ls-basan-instrumented.s -lasan -o ls-basan-instrumented
To generate symbolized assembly that may be modified by hand or post-processed by existing tools:
python3 -m librw.rw </path/to/binary> <path/to/output/asm/files>
Post-modification, the asm files may be assembled to working binaries as described above.
While retrowrite is interoperable with other tools, we strongly encourage researchers to use retrowrite API for their binary instrumentation / modification needs! This saves the additional effort of having to load and parse binaries or assembly files. Check the developer sections for more details on getting started.
To generate an AFL instrumented binary, first generate the symbolized assembly
as described above. Then, recompile the symbolized assembly with afl-gcc from
afl++ like this:
$ AFL_AS_FORCE_INSTRUMENT=1 afl-gcc foo.s -o foo
In general, librw/ contains the code for loading, disassembly, and
symbolization of binaries and forms the core of all transformations.
Individual transformation passes that build on top this rewriting framework,
such as our binary-only Address Sanitizer (BASan) is contained as individual
tools in rwtools/.
See docker for more information on building a docker image for fuzzing and reproducing results.
The following publications cover different parts of the RetroWrite project:
-
RetroWrite: Statically Instrumenting COTS Binaries for Fuzzing and Sanitization Sushant Dinesh, Nathan Burow, Dongyan Xu, and Mathias Payer. In Oakland'20: IEEE International Symposium on Security and Privacy, 2020
-
No source, no problem! High speed binary fuzzing Matteo Rizzo, and Mathias Payer. In 36c3'19: Chaos Communication Congress, 2019
The MIT License
Copyright (c) 2019 HexHive Group, Sushant Dinesh sushant.dinesh94@gmail.com, Matteo Rizzo matteorizzo.personal@gmail.com, Mathias Payer mathias.payer@nebelwelt.net
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
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