blob: acc023a242abc340090707023701b4c936d34acd (
plain)
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
|
// Copyright 2021 Code Intelligence GmbH
//
// 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.
package com.example;
import com.code_intelligence.jazzer.api.FuzzedDataProvider;
import com.code_intelligence.jazzer.api.FuzzerSecurityIssueLow;
import java.util.Base64;
public class ExampleValueProfileFuzzer {
private static String base64(byte[] input) {
return Base64.getEncoder().encodeToString(input);
}
private static long insecureEncrypt(long input) {
long key = 0xefe4eb93215cb6b0L;
return input ^ key;
}
public static void fuzzerTestOneInput(FuzzedDataProvider data) {
// Without -use_value_profile=1, the fuzzer gets stuck here as there is no direct correspondence
// between the input bytes and the compared string. With value profile, the fuzzer can guess the
// expected input byte by byte, which takes linear rather than exponential time.
if (base64(data.consumeBytes(6)).equals("SmF6emVy")) {
long[] plaintextBlocks = data.consumeLongs(2);
if (plaintextBlocks.length != 2)
return;
if (insecureEncrypt(plaintextBlocks[0]) == 0x9fc48ee64d3dc090L) {
// Without --fake_pcs (enabled by default with -use_value_profile=1), the fuzzer would get
// stuck here as the value profile information for long comparisons would not be able to
// distinguish between this comparison and the one above.
if (insecureEncrypt(plaintextBlocks[1]) == 0x888a82ff483ad9c2L) {
mustNeverBeCalled();
}
}
}
}
private static void mustNeverBeCalled() {
throw new FuzzerSecurityIssueLow("mustNeverBeCalled has been called");
}
}
|
