1 //===- FuzzerInternal.h - Internal header for the Fuzzer --------*- C++ -* ===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 // Define the main class fuzzer::Fuzzer and most functions.
10 //===----------------------------------------------------------------------===//
11 #include <cassert>
12 #include <climits>
13 #include <chrono>
14 #include <cstddef>
15 #include <cstdlib>
16 #include <string>
17 #include <vector>
18 #include <unordered_set>
19 
20 #include "FuzzerInterface.h"
21 
22 namespace fuzzer {
23 typedef std::vector<uint8_t> Unit;
24 using namespace std::chrono;
25 
26 std::string FileToString(const std::string &Path);
27 Unit FileToVector(const std::string &Path);
28 void ReadDirToVectorOfUnits(const char *Path, std::vector<Unit> *V);
29 void WriteToFile(const Unit &U, const std::string &Path);
30 void CopyFileToErr(const std::string &Path);
31 // Returns "Dir/FileName" or equivalent for the current OS.
32 std::string DirPlusFile(const std::string &DirPath,
33                         const std::string &FileName);
34 
35 void Mutate(Unit *U, size_t MaxLen);
36 
37 void CrossOver(const Unit &A, const Unit &B, Unit *U, size_t MaxLen);
38 
39 void Print(const Unit &U, const char *PrintAfter = "");
40 void PrintASCII(const Unit &U, const char *PrintAfter = "");
41 std::string Hash(const Unit &U);
42 void SetTimer(int Seconds);
43 
44 class Fuzzer {
45  public:
46   struct FuzzingOptions {
47     int Verbosity = 1;
48     int MaxLen = 0;
49     bool DoCrossOver = true;
50     int  MutateDepth = 5;
51     bool ExitOnFirst = false;
52     bool UseCounters = false;
53     bool UseFullCoverageSet  = false;
54     bool UseCoveragePairs = false;
55     bool UseDFSan = false;
56     int PreferSmallDuringInitialShuffle = -1;
57     size_t MaxNumberOfRuns = ULONG_MAX;
58     std::string OutputCorpus;
59     std::vector<std::string> Tokens;
60   };
61   Fuzzer(UserCallback Callback, FuzzingOptions Options);
AddToCorpus(const Unit & U)62   void AddToCorpus(const Unit &U) { Corpus.push_back(U); }
63   size_t Loop(size_t NumIterations);
64   void ShuffleAndMinimize();
65   void InitializeDFSan();
CorpusSize()66   size_t CorpusSize() const { return Corpus.size(); }
ReadDir(const std::string & Path)67   void ReadDir(const std::string &Path) {
68     ReadDirToVectorOfUnits(Path.c_str(), &Corpus);
69   }
70   // Save the current corpus to OutputCorpus.
71   void SaveCorpus();
72 
secondsSinceProcessStartUp()73   size_t secondsSinceProcessStartUp() {
74     return duration_cast<seconds>(system_clock::now() - ProcessStartTime)
75         .count();
76   }
77 
getTotalNumberOfRuns()78   size_t getTotalNumberOfRuns() { return TotalNumberOfRuns; }
79 
80   static void StaticAlarmCallback();
81 
82   Unit SubstituteTokens(const Unit &U) const;
83 
84  private:
85   void AlarmCallback();
86   void ExecuteCallback(const Unit &U);
87   size_t MutateAndTestOne(Unit *U);
88   size_t RunOne(const Unit &U);
89   size_t RunOneMaximizeTotalCoverage(const Unit &U);
90   size_t RunOneMaximizeFullCoverageSet(const Unit &U);
91   size_t RunOneMaximizeCoveragePairs(const Unit &U);
92   void WriteToOutputCorpus(const Unit &U);
93   void WriteToCrash(const Unit &U, const char *Prefix);
94   bool MutateWithDFSan(Unit *U);
95   void PrintStats(const char *Where, size_t Cov, const char *End = "\n");
96   void PrintUnitInASCIIOrTokens(const Unit &U, const char *PrintAfter = "");
97 
98   void SetDeathCallback();
99   static void StaticDeathCallback();
100   void DeathCallback();
101   Unit CurrentUnit;
102 
103   size_t TotalNumberOfRuns = 0;
104 
105   std::vector<Unit> Corpus;
106   std::unordered_set<uintptr_t> FullCoverageSets;
107   std::unordered_set<uint64_t>  CoveragePairs;
108 
109   // For UseCounters
110   std::vector<uint8_t> CounterBitmap;
TotalBits()111   size_t TotalBits() {  // Slow. Call it only for printing stats.
112     size_t Res = 0;
113     for (auto x : CounterBitmap) Res += __builtin_popcount(x);
114     return Res;
115   }
116 
117   UserCallback Callback;
118   FuzzingOptions Options;
119   system_clock::time_point ProcessStartTime = system_clock::now();
120   system_clock::time_point UnitStartTime;
121   long TimeOfLongestUnitInSeconds = 0;
122 };
123 
124 };  // namespace fuzzer
125