1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
|
#!/usr/bin/env python
# Copyright 2017 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""
Script for generating .proto and a conversion .cc file for a templated library
based JavaScript parser fuzzer.
"""
import sys
def ParseWord(word_string):
# Every part of the word is either a string surrounded by "" or a placeholder
# $<int>.
word_string = word_string.lstrip().rstrip()
parts = []
while len(word_string) > 0:
if word_string[0] == '"':
end_ix = 1 + word_string[1:].index('"')
parts.append(word_string[1:end_ix])
word_string = word_string[(end_ix + 1):]
elif word_string[0] == '$':
if ' ' in word_string:
end_ix = word_string.index(' ')
else:
end_ix = len(word_string)
parts.append(int(word_string[1:end_ix]))
word_string = word_string[end_ix:]
else:
assert(False)
word_string = word_string.lstrip()
return parts
def GenerateProtoContents(words):
contents = ''
for ix in range(len(words)):
contents += ' token_value_' + str(ix) + ' = ' + str(ix) + ';\n'
return contents
def GenerateConversionContents(words):
contents = ''
ix = 0
for word in words:
contents += ' case ' + str(ix) + ':\n'
max_part = -1
first = True
building_string = ''
for part in word:
if not first:
building_string += ' + std::string(" ") + '
if isinstance(part, str):
building_string += 'std::string("' + part + '")'
else:
if (part > max_part):
max_part = part
building_string += ('token_to_string(token.inner_tokens(' + str(part) +
'), depth)')
first = False
if max_part >= 0:
contents += (' if (token.inner_tokens().size() < ' +
str(max_part + 1) + ') return std::string("");\n')
contents += ' return ' + building_string + ';\n'
ix += 1
return contents
def ReadDictionary(filename):
with open(filename) as input_file:
lines = input_file.readlines()
words = []
for line in lines:
if not line.startswith('#'):
word = ParseWord(line)
if len(word) > 0:
words.append(word)
return words
def main(argv):
output_proto_file = argv[1]
output_cc_file = argv[2]
input_dict_file = argv[3]
words = ReadDictionary(input_dict_file)
proto_header = ('// Generated by generate_javascript_parser_proto.py.\n'
'\n'
'syntax = "proto2";\n'
'package javascript_parser_proto_fuzzer;\n'
'\n'
'message Token {\n'
' enum Value {\n')
proto_footer = (' }\n'
' required Value value = 1;\n'
' repeated Token inner_tokens = 2;\n'
'}\n'
'\n'
'message Source {\n'
' required bool is_module = 1;\n'
' repeated Token tokens = 2;\n'
'}\n')
proto_contents = proto_header + GenerateProtoContents(words) + proto_footer
with open(output_proto_file, 'w') as f:
f.write(proto_contents)
conversion_header = (
'// Generated by generate_javascript_parser_proto.py.\n'
'\n'
'#include "testing/libfuzzer/fuzzers/'
'javascript_parser_proto_to_string.h"\n'
'\n'
'// Bound calls to token_to_string to prevent memory usage from growing\n'
'// too much.\n'
'const int kMaxRecursiveDepth = 9;\n'
'\n'
'std::string token_to_string(\n'
' const javascript_parser_proto_fuzzer::Token& token, int depth)'
' {\n'
' if (++depth == kMaxRecursiveDepth) return std::string("");\n'
' switch(token.value()) {\n')
conversion_footer = (' default: break;\n'
' }\n'
' return std::string("");\n'
'}\n')
conversion_contents = (conversion_header + GenerateConversionContents(words)
+ conversion_footer)
with open(output_cc_file, 'w') as f:
f.write(conversion_contents)
if __name__ == "__main__":
main(sys.argv)
|
