#!/usr/bin/env vpython3
# Copyright 2019 The Chromium Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""
Extracts network traffic annotation definitions from C++ source code.
"""
from __future__ import print_function
import argparse
import re
import sys
import traceback
from annotation_tools import NetworkTrafficAnnotationTools
from annotation_tokenizer import Tokenizer, SourceCodeParsingError
from enum import Enum
from pathlib import Path
from typing import List, Dict, NamedTuple
class AnnotationType(Enum):
COMPLETE = 'Definition'
PARTIAL = 'Partial'
COMPLETING = 'Completing'
BRANCHED_COMPLETING = 'BranchedCompleting'
MUTABLE = 'Mutable'
class Language(NamedTuple):
"""Info on how to parse a given programming language's source code."""
# Human-readable name, for debugging.
name: str
# Maps definition function names to the type of annotation they define.
annotation_types: Dict[str, AnnotationType]
# Regex that matches an annotation definition. Capture group 1 of this regex
# should contain a function name that can be mapped via annotation_types.
call_detection_regex: re.Pattern
# Exit code for parsing errors. Other runtime errors return 1.
EX_PARSE_ERROR = 2
# A regex that scans more quickly than the other regexen below, for
# pre-filtering. A first pass will check for these strings, and skip any files
# that don't contain them. Keep this regex simple, so it's fast.
#
# N.B.: this regex MUST match anything that would be matched by the other
# regexen below, or we will get false negatives (i.e., we will miss some
# annotations because pre-filtering is too strict).
PREFILTER_REGEX = re.compile(r'''
TrafficAnnotation | TRAFFIC_ANNOTATION
''', re.VERBOSE | re.IGNORECASE)
# Language definition for C++ source files.
CPP_ANNOTATION_TYPES = {
'DefineNetworkTrafficAnnotation': AnnotationType.COMPLETE,
'DefinePartialNetworkTrafficAnnotation': AnnotationType.PARTIAL,
'CompleteNetworkTrafficAnnotation': AnnotationType.COMPLETING,
'BranchedCompleteNetworkTrafficAnnotation':
AnnotationType.BRANCHED_COMPLETING,
'CreateMutableNetworkTrafficAnnotationTag': AnnotationType.MUTABLE,
}
CPP_LANGUAGE = Language(name='C++',
annotation_types=CPP_ANNOTATION_TYPES,
call_detection_regex=re.compile(
r'''
\b
# Look for one of the tracked function names.
# Capture group 1: function name.
(
''' + ('|'.join(CPP_ANNOTATION_TYPES.keys())) + r'''
)
# Followed by a left-paren.
\s*
\(
''', re.VERBOSE | re.DOTALL))
# Language definition for Java source files.
JAVA_ANNOTATION_TYPES = {
'createComplete': AnnotationType.COMPLETE,
}
JAVA_LANGUAGE = Language(name='Java',
annotation_types=JAVA_ANNOTATION_TYPES,
call_detection_regex=re.compile(
r'''
\b
# Look for a string like NetworkTrafficAnnotationTag.<methodName>
NetworkTrafficAnnotationTag \s* \. \s*
# Capture group 1: method name.
(
''' + ('|'.join(JAVA_ANNOTATION_TYPES.keys())) + r'''
)
# Followed by a left-paren.
\s*
\(
''', re.VERBOSE | re.DOTALL))
# Maps file extensions to their Language definition.
LANGUAGE_MAPPING: Dict[str, Language] = {
'.cc': CPP_LANGUAGE,
'.mm': CPP_LANGUAGE,
'.java': JAVA_LANGUAGE,
}
# Regex that matches an annotation that should only be used in test files.
TEST_ANNOTATION_REGEX = re.compile(
r'\b(PARTIAL_)?TRAFFIC_ANNOTATION_FOR_TESTS\b')
# Regex that matches a placeholder annotation for a few whitelisted files.
MISSING_ANNOTATION_REGEX = re.compile(r'\bMISSING_TRAFFIC_ANNOTATION\b')
# Regex that matches placeholder annotations for unsupported platforms that
# don't require Network Traffic Annotations compliance. (e.g. iOS)
NO_ANNOTATION_REGEX = re.compile(r'\bNO_TRAFFIC_ANNOTATION_YET\b')
# List of supported file extensions for source code.
SUPPORTED_EXTENSIONS = set(LANGUAGE_MAPPING.keys())
class Annotation:
"""A network annotation definition in C++ code."""
def __init__(self,
language: Language,
file_path: Path,
line_number: int,
type_name: AnnotationType,
unique_id='',
extra_id='',
text=''):
"""Constructs an Annotation object with the given field values.
Args:
file_path: Path to the file that contains this annotation.
"""
self.language = language
self.file_path = file_path
self.line_number = line_number
self.type_name = type_name
self.unique_id = unique_id
self.extra_id = extra_id
self.text = text
def parse_definition(self, re_match: re.Match):
"""Parses the annotation and populates object fields.
Args:
re_match: A Match obtained from the Language's call_detection_regex.
"""
definition_function = re_match.group(1)
self.type_name = self.language.annotation_types[definition_function]
# Parse the arguments given to the definition function, populating
# |unique_id|, |text| and (possibly) |extra_id|.
body = re_match.string[re_match.end():]
self._parse_body(body)
def extractor_output_string(self) -> str:
"""Returns a string formatted for output."""
return '\n'.join(
map(str, [
'==== NEW ANNOTATION ====',
self.file_path,
self.line_number,
self.type_name.value,
self.unique_id,
self.extra_id,
self.text,
'==== ANNOTATION ENDS ====',
]))
def _parse_body(self, body: str):
"""Tokenizes and parses the arguments given to the definition function."""
# Don't bother parsing CreateMutableNetworkTrafficAnnotationTag(), we don't
# care about its arguments anyways.
if self.type_name == AnnotationType.MUTABLE:
return
tokenizer = Tokenizer(body, self.file_path, self.line_number)
# unique_id
self.unique_id = tokenizer.advance('string_literal')
tokenizer.advance('comma')
# extra_id (Partial/BranchedCompleting)
if self.type_name in [
AnnotationType.PARTIAL, AnnotationType.BRANCHED_COMPLETING
]:
self.extra_id = tokenizer.advance('string_literal')
tokenizer.advance('comma')
# partial_annotation (Completing/BranchedCompleting)
if self.type_name in [
AnnotationType.COMPLETING, AnnotationType.BRANCHED_COMPLETING
]:
# Skip the |partial_annotation| argument. It can be a variable_name, or a
# FunctionName(), so skip the parentheses if they're there.
tokenizer.advance('symbol')
if tokenizer.maybe_advance('left_paren'):
tokenizer.advance('right_paren')
tokenizer.advance('comma')
# proto text
self.text = tokenizer.advance('string_literal')
# The function call should end here without any more arguments.
assert tokenizer.advance('right_paren')
def get_line_number_at(string, pos):
"""Find the line number for the char at position |pos|. 1-indexed."""
# This is inefficient: O(n). But we only run it once for each annotation
# definition, so the effect on total runtime is negligible.
return 1 + len(re.compile(r'\n').findall(string[:pos]))
def is_inside_comment(string, pos):
"""Checks if the position |pos| within string seems to be inside a comment.
This is a bit naive. Only checks for single-line comments (// ...), not block
comments (/* ... */).
Args:
string: string to scan.
pos: position within the string.
Returns:
True if |string[pos]| looks like it's inside a C++ comment.
"""
# Look for "//" on the same line in the reversed string.
return bool(re.match(r'[^\n]*//', string[pos::-1]))
# TODO(crbug.com/40629071): Add multi-line comment support.
def may_contain_annotations(file_contents: str) -> bool:
"""Returns False if |file_path| is guaranteed not to contain annotations.
This runs much faster than extract_annotations(), and is meant for
pre-filtering. If this returns True, then |file_path| *might* contain
annotations. Call extract_annotations() to know for sure."""
return bool(PREFILTER_REGEX.search(file_contents))
def extract_annotations(file_path: Path, contents: str) -> List[Annotation]:
"""Extracts and returns annotations from the file at |file_path|."""
if file_path.suffix not in LANGUAGE_MAPPING:
raise ValueError("Unrecognized extension '{}' for file '{}'.".format(
file_path.suffix, str(file_path)))
language = LANGUAGE_MAPPING[file_path.suffix]
defs = []
# Check for function calls (e.g. DefineNetworkTrafficAnnotation(...))
for re_match in language.call_detection_regex.finditer(contents):
if is_inside_comment(re_match.string, re_match.start()):
continue
line_number = get_line_number_at(contents, re_match.start())
annotation = Annotation(language, file_path, line_number,
AnnotationType.COMPLETE)
annotation.parse_definition(re_match)
defs.append(annotation)
# Check for test annotations (e.g. TRAFFIC_ANNOTATION_FOR_TESTS)
for re_match in TEST_ANNOTATION_REGEX.finditer(contents):
if is_inside_comment(re_match.string, re_match.start()):
continue
line_number = get_line_number_at(contents, re_match.start())
is_partial = bool(re_match.group(1))
if is_partial:
type_name = AnnotationType.PARTIAL
unique_id = 'test_partial'
extra_id = 'test'
else:
type_name = AnnotationType.COMPLETE
unique_id = 'test'
extra_id = ''
annotation = Annotation(
language,
file_path,
line_number,
type_name=type_name,
unique_id=unique_id,
extra_id=extra_id,
text='Traffic annotation for unit, browser and other tests')
defs.append(annotation)
# Check for MISSING_TRAFFIC_ANNOTATION.
for re_match in MISSING_ANNOTATION_REGEX.finditer(contents):
if is_inside_comment(re_match.string, re_match.start()):
continue
line_number = get_line_number_at(contents, re_match.start())
annotation = Annotation(language,
file_path,
line_number,
type_name=AnnotationType.COMPLETE,
unique_id='missing',
text='Function called without traffic annotation.')
defs.append(annotation)
# Check for NO_TRAFFIC_ANNOTATION_YET.
for re_match in NO_ANNOTATION_REGEX.finditer(contents):
if is_inside_comment(re_match.string, re_match.start()):
continue
line_number = get_line_number_at(contents, re_match.start())
annotation = Annotation(language,
file_path,
line_number,
type_name=AnnotationType.COMPLETE,
unique_id='undefined',
text='Nothing here yet.')
defs.append(annotation)
return defs
def main():
parser = argparse.ArgumentParser()
parser.add_argument('--options-file',
type=Path,
help='optional file to read options from')
args, argv = parser.parse_known_args()
if args.options_file is not None:
argv = args.options_file.read_text(encoding="utf-8").split()
parser.add_argument(
'--build-path',
type=Path,
help='Specifies a compiled build directory, e.g. out/Debug.')
parser.add_argument(
'--generate-compdb', action='store_true',
help='Generate a new compile_commands.json before running')
parser.add_argument(
'--no-filter', action='store_true',
help='Do not filter files based on compdb entries')
parser.add_argument('file_paths',
nargs='+',
type=Path,
help='List of files to process.')
args = parser.parse_args(argv)
if not args.no_filter:
tools = NetworkTrafficAnnotationTools(args.build_path)
compdb_files = tools.GetCompDBFiles(args.generate_compdb)
annotation_definitions = []
# Parse all the files.
# TODO(crbug.com/40629071): Do this in parallel.
for file_path in args.file_paths:
if not args.no_filter and file_path.resolve() not in compdb_files:
continue
try:
annotation_definitions.extend(
extract_annotations(file_path, file_path.read_text(encoding="utf-8")))
except SourceCodeParsingError:
traceback.print_exc()
return EX_PARSE_ERROR
# Print output.
for annotation in annotation_definitions:
print(annotation.extractor_output_string())
# If all files were successfully checked for annotations but none of them had
# any, print something so that the traffic_annotation_auditor knows there was
# no error so that the files get checked for deleted annotations.
if not annotation_definitions:
print('No annotations in these files.')
return 0
if '__main__' == __name__:
sys.exit(main())