fuzzing/tools/launcher.py

#
# 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
#
#    https://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.

# Lint as: python3
"""
This is the launcher script to provide a uniform command line interface 
behind a number of arbitrary fuzzing engines.
"""

from absl import app
from absl import flags
import os

FLAGS = flags.FLAGS

flags.DEFINE_bool(
    "regression", False,
    "If set True, the script will trigger the target as a regression test.")

flags.DEFINE_enum(
    "engine", "default", ["default", "libfuzzer"],
    "The type of the engine, the default is to run a gUnit test.")

flags.DEFINE_integer(
    "timeout_secs",
    0,
    "The maximum duration, in seconds, of the fuzzer run launched.",
    lower_bound=0)

flags.DEFINE_list(
    "fuzzer_extra_args", None,
    "If non-empty, the elements will be passed to the fuzzer as arguments.")

flags.DEFINE_string(
    "corpus_dir", "",
    "If non-empty, a directory that will be used as a seed corpus for the fuzzer."
)

flags.DEFINE_string("dict", "",
                    "If non-empty, a dictionary file of input keywords.")


def main(argv):
    if len(argv) != 2:
        raise app.UsageError(
            "This script receives 1 argument. It should look like:" +
            "\n\tpython " + __file__ + " EXECUTABLE")

    command_args = [argv[1]]
    if FLAGS.engine == "libfuzzer":
        command_args.append("-max_total_time=" + str(FLAGS.timeout_secs))
        command_args.append("-timeout=" + str(FLAGS.timeout_secs))
        if FLAGS.regression:
            command_args.append("-runs=0")
        if FLAGS.dict:
            command_args.append("-dict=" + FLAGS.dict)
    if FLAGS.corpus_dir:
        command_args.append(FLAGS.corpus_dir)
    if FLAGS.fuzzer_extra_args:
        command_args.extend(FLAGS.fuzzer_extra_args)
    os.execv(argv[1], command_args)


if __name__ == "__main__":
    app.run(main)