Add a fuzzer for scapy (#4897)

* Add a fuzzer for scapy

* Add a proper™ contact for scapy's fuzzer

* Fix wrapper to match docs (for symbolization)

Co-authored-by: Abhishek Arya <inferno@chromium.org>

projects/scapy/Dockerfile

@@ -0,0 +1,26 @@
+# Copyright 2019 Google Inc.
+#
+# 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/oss-fuzz-base/base-builder
+
+RUN git clone \
+	--depth 1 \
+	--branch master \
+	https://github.com/secdev/scapy.git
+
+WORKDIR scapy
+
+COPY build.sh pcap_fuzzer.py $SRC/

projects/scapy/build.sh

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+#!/bin/bash -eu
+# Copyright 2020 Google Inc.
+#
+# 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.
+#
+################################################################################
+
+# Build and install project (using current CFLAGS, CXXFLAGS).
+pip3 install .
+
+# Build fuzzers in $OUT.
+for fuzzer in $(find $SRC -name '*_fuzzer.py'); do
+  fuzzer_basename=$(basename -s .py $fuzzer)
+  fuzzer_package=${fuzzer_basename}.pkg
+  pyinstaller --distpath $OUT --onefile --name $fuzzer_package $fuzzer
+
+  # Create execution wrapper.
+  echo "#!/bin/sh
+# LLVMFuzzerTestOneInput for fuzzer detection.
+this_dir=\$(dirname \"\$0\")
+ASAN_OPTIONS=\$ASAN_OPTIONS:symbolize=1:external_symbolizer_path=\$this_dir/llvm-symbolizer:detect_leaks=0 \
+\$this_dir/$fuzzer_package \$@" > $OUT/$fuzzer_basename
+  chmod u+x $OUT/$fuzzer_basename
+done
+
+zip -j $OUT/pcap_fuzzer_seed_corpus.zip test/pcaps/*

projects/scapy/pcap_fuzzer.py

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+#!/usr/bin/python3
+
+# 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.
+
+import io
+import sys
+import atheris
+
+import scapy
+import scapy.error
+import scapy.utils
+
+
+def TestOneInput(input_bytes):
+  try:
+    scapy.utils.rdpcap(io.BytesIO(input_bytes))
+  except scapy.error.Scapy_Exception:
+    pass
+
+
+def main():
+  atheris.Setup(sys.argv, TestOneInput, enable_python_coverage=True)
+  atheris.Fuzz()
+
+
+if __name__ == "__main__":
+  main()

projects/scapy/project.yaml

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+homepage: "https://scapy.net"
+main_repo: "https://github.com/secdev/scapy"
+language: python
+primary_contact: "guillaume@valadon.net"
+auto_ccs:
+  - "jvoisin@google.com"
+  - "ipudney@google.com"
+fuzzing_engines:
+  - libfuzzer
+sanitizers:
+  - address
+  - undefined