1 files changed, 108 insertions, 0 deletions
diff --git a/infra/cifuzz/fuzz_target.py b/infra/cifuzz/fuzz_target.py
new file mode 100644
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+++ b/infra/cifuzz/fuzz_target.py
@@ -0,0 +1,108 @@
+# 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.
+"""A module to handle running a fuzz target for a specified amount of time."""
+import logging
+import os
+import re
+import subprocess
+import sys
+
+# pylint: disable=wrong-import-position
+sys.path.append(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
+import utils
+
+# TODO: Turn default logging to WARNING when CIFuzz is stable
+logging.basicConfig(
+    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s',
+    level=logging.DEBUG)
+
+
+class FuzzTarget:
+  """A class to manage a single fuzz target.
+
+  Attributes:
+    project_name: The name of the OSS-Fuzz project the target is associated.
+    target_name: The name of the fuzz target.
+    duration: The length of time in seconds that the target should run.
+    target_path: The location of the fuzz target binary.
+  """
+
+  def __init__(self, project_name, target_path, duration, out_dir):
+    """Represents a single fuzz target.
+
+    Args:
+      project_name: The OSS-Fuzz project of this target.
+      target_path: The location of the fuzz target binary.
+      duration: The length of time  in seconds the target should run.
+      out_dir: The location of where the output from crashes should be stored.
+    """
+    self.target_name = os.path.basename(target_path)
+    self.duration = duration
+    self.project_name = project_name
+    self.target_path = target_path
+    self.out_dir = out_dir
+
+  def fuzz(self):
+    """Starts the fuzz target run for the length of time specified by duration.
+
+    Returns:
+      (test_case, stack trace) if found or (None, None) on timeout or error.
+    """
+    logging.info('Fuzzer %s, started.', self.target_name)
+    docker_container = utils.get_container_name()
+    command = ['docker', 'run', '--rm', '--privileged']
+    if docker_container:
+      command += [
+          '--volumes-from', docker_container, '-e', 'OUT=' + self.out_dir
+      ]
+    else:
+      command += ['-v', '%s:%s' % (self.out_dir, '/out')]
+
+    command += [
+        '-e', 'FUZZING_ENGINE=libfuzzer', '-e', 'SANITIZER=address', '-e',
+        'RUN_FUZZER_MODE=interactive', 'gcr.io/oss-fuzz-base/base-runner',
+        'bash', '-c', 'run_fuzzer {0}'.format(self.target_name)
+    ]
+    logging.info('Running command: %s', ' '.join(command))
+    process = subprocess.Popen(command,
+                               stdout=subprocess.PIPE,
+                               stderr=subprocess.PIPE)
+
+    try:
+      _, err = process.communicate(timeout=self.duration)
+    except subprocess.TimeoutExpired:
+      logging.info('Fuzzer %s, finished with timeout.', self.target_name)
+      return None, None
+
+    logging.info('Fuzzer %s, ended before timeout.', self.target_name)
+    err_str = err.decode('ascii')
+    test_case = self.get_test_case(err_str)
+    if not test_case:
+      logging.error('No test case found in stack trace.', file=sys.stderr)
+      return None, None
+    return test_case, err_str
+
+  def get_test_case(self, error_string):
+    """Gets the file from a fuzzer run stack trace.
+
+    Args:
+      error_string: The stack trace string containing the error.
+
+    Returns:
+      The error test case or None if not found.
+    """
+    match = re.search(r'\bTest unit written to \.\/([^\s]+)', error_string)
+    if match:
+      return os.path.join(self.out_dir, match.group(1))
+    return None