Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Seed experiment #2025

Open
wants to merge 15 commits into
base: master
Choose a base branch
from
33 changes: 33 additions & 0 deletions fuzzers/afl_empty_seeds/builder.Dockerfile
Original file line number Diff line number Diff line change
@@ -0,0 +1,33 @@
# Copyright 2020 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

ARG parent_image
FROM $parent_image

# Download and compile AFL v2.57b.
# Set AFL_NO_X86 to skip flaky tests.
RUN git clone \
--depth 1 \
--branch v2.57b \
https://github.com/google/AFL.git /afl && \
cd /afl && \
CFLAGS= CXXFLAGS= AFL_NO_X86=1 make

# Use afl_driver.cpp from LLVM as our fuzzing library.
RUN apt-get update && \
apt-get install wget -y && \
wget https://raw.githubusercontent.com/llvm/llvm-project/5feb80e748924606531ba28c97fe65145c65372e/compiler-rt/lib/fuzzer/afl/afl_driver.cpp -O /afl/afl_driver.cpp && \
clang -Wno-pointer-sign -c /afl/llvm_mode/afl-llvm-rt.o.c -I/afl && \
clang++ -stdlib=libc++ -std=c++11 -O2 -c /afl/afl_driver.cpp && \
ar r /libAFL.a *.o
152 changes: 152 additions & 0 deletions fuzzers/afl_empty_seeds/fuzzer.py
Original file line number Diff line number Diff line change
@@ -0,0 +1,152 @@
# Copyright 2020 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Integration code for AFL fuzzer."""

import json
import os
import shutil
import subprocess

from fuzzers import utils


def prepare_build_environment():
"""Set environment variables used to build targets for AFL-based
fuzzers."""
cflags = ['-fsanitize-coverage=trace-pc-guard']
utils.append_flags('CFLAGS', cflags)
utils.append_flags('CXXFLAGS', cflags)

os.environ['CC'] = 'clang'
os.environ['CXX'] = 'clang++'
os.environ['FUZZER_LIB'] = '/libAFL.a'


def build():
"""Build benchmark."""
prepare_build_environment()

utils.build_benchmark()

print('[post_build] Copying afl-fuzz to $OUT directory')
# Copy out the afl-fuzz binary as a build artifact.
shutil.copy('/afl/afl-fuzz', os.environ['OUT'])


def get_stats(output_corpus, fuzzer_log): # pylint: disable=unused-argument
"""Gets fuzzer stats for AFL."""
# Get a dictionary containing the stats AFL reports.
stats_file = os.path.join(output_corpus, 'fuzzer_stats')
if not os.path.exists(stats_file):
print('Can\'t find fuzzer_stats')
return '{}'
with open(stats_file, encoding='utf-8') as file_handle:
stats_file_lines = file_handle.read().splitlines()
stats_file_dict = {}
for stats_line in stats_file_lines:
key, value = stats_line.split(': ')
stats_file_dict[key.strip()] = value.strip()

# Report to FuzzBench the stats it accepts.
stats = {'execs_per_sec': float(stats_file_dict['execs_per_sec'])}
return json.dumps(stats)


def prepare_fuzz_environment(input_corpus):
"""Prepare to fuzz with AFL or another AFL-based fuzzer."""
# Tell AFL to not use its terminal UI so we get usable logs.
os.environ['AFL_NO_UI'] = '1'
# Skip AFL's CPU frequency check (fails on Docker).
os.environ['AFL_SKIP_CPUFREQ'] = '1'
# No need to bind affinity to one core, Docker enforces 1 core usage.
os.environ['AFL_NO_AFFINITY'] = '1'
# AFL will abort on startup if the core pattern sends notifications to
# external programs. We don't care about this.
os.environ['AFL_I_DONT_CARE_ABOUT_MISSING_CRASHES'] = '1'
# Don't exit when crashes are found. This can happen when corpus from
# OSS-Fuzz is used.
os.environ['AFL_SKIP_CRASHES'] = '1'
# Shuffle the queue
os.environ['AFL_SHUFFLE_QUEUE'] = '1'

# AFL needs at least one non-empty seed to start.
utils.create_seed_file_for_empty_corpus(input_corpus)


def check_skip_det_compatible(additional_flags):
""" Checks if additional flags are compatible with '-d' option"""
# AFL refuses to take in '-d' with '-M' or '-S' options for parallel mode.
# (cf. https://github.com/google/AFL/blob/8da80951/afl-fuzz.c#L7477)
if '-M' in additional_flags or '-S' in additional_flags:
return False
return True


def prepare_empty_corpus(input_corpus):
if os.path.exists(input_corpus):
shutil.rmtree(input_corpus)
os.makedirs(input_corpus)
with open(os.path.join(input_corpus, 'a'), 'wb') as f:
f.write(b'a')


def run_afl_fuzz(input_corpus,
output_corpus,
target_binary,
additional_flags=None,
hide_output=False):
"""Run afl-fuzz."""

prepare_empty_corpus(input_corpus)
# Spawn the afl fuzzing process.
print('[run_afl_fuzz] Running target with afl-fuzz')
command = [
'./afl-fuzz',
'-i',
input_corpus,
'-o',
output_corpus,
# Use no memory limit as ASAN doesn't play nicely with one.
'-m',
'none',
'-t',
'1000+', # Use same default 1 sec timeout, but add '+' to skip hangs.
]
# Use '-d' to skip deterministic mode, as long as it it compatible with
# additional flags.
if not additional_flags or check_skip_det_compatible(additional_flags):
command.append('-d')
if additional_flags:
command.extend(additional_flags)
dictionary_path = utils.get_dictionary_path(target_binary)

# if dictionary_path:
# command.extend(['-x', dictionary_path])
command += [
'--',
target_binary,
# Pass INT_MAX to afl the maximize the number of persistent loops it
# performs.
'2147483647'
]
print('[run_afl_fuzz] Running command: ' + ' '.join(command))
output_stream = subprocess.DEVNULL if hide_output else None
subprocess.check_call(command, stdout=output_stream, stderr=output_stream)


def fuzz(input_corpus, output_corpus, target_binary):
"""Run afl-fuzz on target."""
prepare_fuzz_environment(input_corpus)

run_afl_fuzz(input_corpus, output_corpus, target_binary)
15 changes: 15 additions & 0 deletions fuzzers/afl_empty_seeds/runner.Dockerfile
Original file line number Diff line number Diff line change
@@ -0,0 +1,15 @@
# Copyright 2020 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

FROM gcr.io/fuzzbench/base-image
49 changes: 49 additions & 0 deletions fuzzers/aflplusplus_empty_seeds/builder.Dockerfile
Original file line number Diff line number Diff line change
@@ -0,0 +1,49 @@
# Copyright 2020 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

ARG parent_image
FROM $parent_image

RUN apt-get update && \
apt-get install -y \
build-essential \
python3-dev \
python3-setuptools \
automake \
cmake \
git \
flex \
bison \
libglib2.0-dev \
libpixman-1-dev \
cargo \
libgtk-3-dev \
# for QEMU mode
ninja-build \
gcc-$(gcc --version|head -n1|sed 's/\..*//'|sed 's/.* //')-plugin-dev \
libstdc++-$(gcc --version|head -n1|sed 's/\..*//'|sed 's/.* //')-dev

# Download afl++.
RUN git clone -b dev https://github.com/AFLplusplus/AFLplusplus /afl && \
cd /afl && \
git checkout 56d5aa3101945e81519a3fac8783d0d8fad82779 || \
true

# Build without Python support as we don't need it.
# Set AFL_NO_X86 to skip flaky tests.
RUN cd /afl && \
unset CFLAGS CXXFLAGS && \
export CC=clang AFL_NO_X86=1 && \
PYTHON_INCLUDE=/ make && \
cp utils/aflpp_driver/libAFLDriver.a /
14 changes: 14 additions & 0 deletions fuzzers/aflplusplus_empty_seeds/description.md
Original file line number Diff line number Diff line change
@@ -0,0 +1,14 @@
# aflplusplus

AFL++ fuzzer instance that has the following config active for all benchmarks:
- PCGUARD instrumentation
- cmplog feature
- dict2file feature
- "fast" power schedule
- persistent mode + shared memory test cases

Repository: [https://github.com/AFLplusplus/AFLplusplus/](https://github.com/AFLplusplus/AFLplusplus/)

[builder.Dockerfile](builder.Dockerfile)
[fuzzer.py](fuzzer.py)
[runner.Dockerfile](runner.Dockerfile)
Loading
Loading