1 // This file is distributed under the University of Illinois Open Source
2 // License. See LICENSE.TXT for details.
3 
4 // Simple test for a cutom crossover.
5 #include <assert.h>
6 #include <cstddef>
7 #include <cstdint>
8 #include <cstdlib>
9 #include <iostream>
10 #include <ostream>
11 #include <random>
12 #include <string.h>
13 #include <functional>
14 
15 static const char *Separator = "-########-";
16 static const char *Target = "A-########-B";
17 
18 static volatile int sink;
19 
20 extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
21   assert(Data);
22   std::string Str(reinterpret_cast<const char *>(Data), Size);
23   static const size_t TargetHash = std::hash<std::string>{}(std::string(Target));
24   size_t StrHash = std::hash<std::string>{}(Str);
25 
26   // Ensure we have 'A' and 'B' in the corpus.
27   if (Size == 1 && *Data == 'A')
28     sink++;
29   if (Size == 1 && *Data == 'B')
30     sink--;
31 
32   if (TargetHash == StrHash) {
33     std::cout << "BINGO; Found the target, exiting\n" << std::flush;
34     exit(1);
35   }
36   return 0;
37 }
38 
39 extern "C" size_t LLVMFuzzerCustomCrossOver(const uint8_t *Data1, size_t Size1,
40                                             const uint8_t *Data2, size_t Size2,
41                                             uint8_t *Out, size_t MaxOutSize,
42                                             unsigned int Seed) {
43   static size_t Printed;
44   static size_t SeparatorLen = strlen(Separator);
45 
46   if (Printed++ < 32)
47     std::cerr << "In LLVMFuzzerCustomCrossover " << Size1 << " " << Size2 << "\n";
48 
49   size_t Size = Size1 + Size2 + SeparatorLen;
50 
51   if (Size > MaxOutSize)
52     return 0;
53 
54   memcpy(Out, Data1, Size1);
55   memcpy(Out + Size1, Separator, SeparatorLen);
56   memcpy(Out + Size1 + SeparatorLen, Data2, Size2);
57 
58   return Size;
59 }
60