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diff --git a/docs/binaryonly_fuzzing.txt b/docs/binaryonly_fuzzing.txt deleted file mode 100644 index 239fb4b0..00000000 --- a/docs/binaryonly_fuzzing.txt +++ /dev/null @@ -1,144 +0,0 @@ - -Fuzzing binary-only programs with afl++ -======================================= - -afl++, libfuzzer and others are great if you have the source code, and -it allows for very fast and coverage guided fuzzing. - -However, if there is only the binary program and not source code available, -then standard afl++ (dumb mode) is not effective. - -The following is a description of how these can be fuzzed with afl++ - -!!!!! -TL;DR: try DYNINST with afl-dyninst. If it produces too many crashes then - use afl -Q qemu_mode, or better: use both in parallel. -!!!!! - - -QEMU ----- -Qemu is the "native" solution to the program. -It is available in the ./qemu_mode/ directory and once compiled it can -be accessed by the afl-fuzz -Q command line option. -The speed decrease is at about 50% -It is the easiest to use alternative and even works for cross-platform binaries. - -As it is included in afl++ this needs no URL. - -WINE+QEMU ---------- -Wine mode can run Win32 PE with the QEMU instrumentation. -It needs Wine, python3 and the pefile python package installed. - -UNICORN -------- -Unicorn is a fork of QEMU. The instrumentation is, therefore, very similar. -In contrast to QEMU, Unicorn does not offer a full system or even userland emulation. -Runtime environment and/or loaders have to be written from scratch, if needed. -On top, block chaining has been removed. This means the speed boost introduced in -to the patched QEMU Mode of afl++ cannot simply be ported over to Unicorn. -For further information, check out ./unicorn_mode.txt. - - -DYNINST -------- -Dyninst is a binary instrumentation framework similar to Pintool and Dynamorio -(see far below). However whereas Pintool and Dynamorio work at runtime, dyninst -instruments the target at load time, and then let it run. -This is great for some things, e.g. fuzzing, and not so effective for others, -e.g. malware analysis. - -So what we can do with dyninst is taking every basic block, and put afl's -instrumention code in there - and then save the binary. -Afterwards we can just fuzz the newly saved target binary with afl-fuzz. -Sounds great? It is. The issue though - it is a non-trivial problem to -insert instructions, which change addresses in the process space, so -everything is still working afterwards. Hence more often than not binaries -crash when they are run (because of instrumentation). - -The speed decrease is about 15-35%, depending on the optimization options -used with afl-dyninst. - -So if dyninst works, it is the best option available. Otherwise it just doesn't -work well. - -https://github.com/vanhauser-thc/afl-dyninst - - -INTEL-PT --------- -If you have a newer Intel CPU, you can make use of Intels processor trace. -The big issue with Intel's PT is the small buffer size and the complex -encoding of the debug information collected through PT. -This makes the decoding very CPU intensive and hence slow. -As a result, the overall speed decrease is about 70-90% (depending on -the implementation and other factors). - -There are two afl intel-pt implementations: - -1. https://github.com/junxzm1990/afl-pt - => this needs Ubuntu 14.04.05 without any updates and the 4.4 kernel. - -2. https://github.com/hunter-ht-2018/ptfuzzer - => this needs a 4.14 or 4.15 kernel. the "nopti" kernel boot option must - be used. This one is faster than the other. - - -CORESIGHT ---------- - -Coresight is ARM's answer to Intel's PT. -There is no implementation so far which handle coresight and getting -it working on an ARM Linux is very difficult due to custom kernel building -on embedded systems is difficult. And finding one that has coresight in -the ARM chip is difficult too. -My guess is that it is slower than Qemu, but faster than Intel PT. -If anyone finds any coresight implementation for afl please ping me: -vh@thc.org - - -PIN & DYNAMORIO ---------------- - -Pintool and Dynamorio are dynamic instrumentation engines, and they can be -used for getting basic block information at runtime. -Pintool is only available for Intel x32/x64 on Linux, Mac OS and Windows -whereas Dynamorio is additionally available for ARM and AARCH64. -Dynamorio is also 10x faster than Pintool. - -The big issue with Dynamorio (and therefore Pintool too) is speed. -Dynamorio has a speed decrease of 98-99% -Pintool has a speed decrease of 99.5% - -Hence Dynamorio is the option to go for if everything fails, and Pintool -only if Dynamorio fails too. - -Dynamorio solutions: - https://github.com/vanhauser-thc/afl-dynamorio - https://github.com/mxmssh/drAFL - https://github.com/googleprojectzero/winafl/ <= very good but windows only - -Pintool solutions: - https://github.com/vanhauser-thc/afl-pin - https://github.com/mothran/aflpin - https://github.com/spinpx/afl_pin_mode <= only old Pintool version supported - - -Non-AFL solutions ------------------ - -There are many binary-only fuzzing frameworks. Some are great for CTFs but don't -work with large binaries, others are very slow but have good path discovery, -some are very hard to set-up ... - -QSYM: https://github.com/sslab-gatech/qsym -Manticore: https://github.com/trailofbits/manticore -S2E: https://github.com/S2E -<please send me any missing that are good> - - - -That's it! -News, corrections, updates? -Email vh@thc.org |