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AFL++ drivers

aflpp_driver

aflpp_driver is used to compile directly libfuzzer LLVMFuzzerTestOneInput() targets.

Just do afl-clang-fast++ -o fuzz fuzzer_harness.cc libAFLDriver.a [plus required linking].

You can also sneakily do this little trick: If this is the clang compile command to build for libfuzzer: clang++ -o fuzz -fsanitize=fuzzer fuzzer_harness.cc -lfoo, then just switch clang++ with afl-clang-fast++ and our compiler will magically insert libAFLDriver.a :)

To use shared-memory test cases, you need nothing to do. To use stdin test cases, give - as the only command line parameter. To use file input test cases, give @@ as the only command line parameter.

IMPORTANT: if you use afl-cmin or afl-cmin.bash, then either pass - or @@ as command line parameters.

aflpp_qemu_driver

Note that you can use the driver too for FRIDA mode (-O).

aflpp_qemu_driver is used for libfuzzer LLVMFuzzerTestOneInput() targets that are to be fuzzed in QEMU mode. So compile them with clang/clang++, without -fsantize=fuzzer or afl-clang-fast, and link in libAFLQemuDriver.a:

clang++ -o fuzz fuzzer_harness.cc libAFLQemuDriver.a [plus required linking].

Then just do (where the name of the binary is fuzz):

AFL_QEMU_PERSISTENT_ADDR=0x$(nm fuzz | grep "T LLVMFuzzerTestOneInput" | awk '{print $1}')
AFL_QEMU_PERSISTENT_HOOK=/path/to/aflpp_qemu_driver_hook.so afl-fuzz -Q ... -- ./fuzz`

if you use afl-cmin or afl-showmap -C with the aflpp_qemu_driver you need to set the set same AFL_QEMU_... (or AFL_FRIDA_...) environment variables. If you want to use afl-showmap (without -C) or afl-cmin.bash, then you may not set these environment variables and rather set AFL_QEMU_DRIVER_NO_HOOK=1.