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 12 #ifndef LLVM_FUZZER_INTERNAL_H 13 #define LLVM_FUZZER_INTERNAL_H 14 15 #include <cassert> 16 #include <climits> 17 #include <chrono> 18 #include <cstddef> 19 #include <cstdlib> 20 #include <string> 21 #include <vector> 22 #include <unordered_set> 23 24 #include "FuzzerInterface.h" 25 26 namespace fuzzer { 27 using namespace std::chrono; 28 29 std::string FileToString(const std::string &Path); 30 Unit FileToVector(const std::string &Path); 31 void ReadDirToVectorOfUnits(const char *Path, std::vector<Unit> *V, 32 long *Epoch); 33 void WriteToFile(const Unit &U, const std::string &Path); 34 void CopyFileToErr(const std::string &Path); 35 // Returns "Dir/FileName" or equivalent for the current OS. 36 std::string DirPlusFile(const std::string &DirPath, 37 const std::string &FileName); 38 39 void Printf(const char *Fmt, ...); 40 void Print(const Unit &U, const char *PrintAfter = ""); 41 void PrintASCII(const Unit &U, const char *PrintAfter = ""); 42 std::string Hash(const Unit &U); 43 void SetTimer(int Seconds); 44 std::string Base64(const Unit &U); 45 int ExecuteCommand(const std::string &Command); 46 47 // Private copy of SHA1 implementation. 48 static const int kSHA1NumBytes = 20; 49 // Computes SHA1 hash of 'Len' bytes in 'Data', writes kSHA1NumBytes to 'Out'. 50 void ComputeSHA1(const uint8_t *Data, size_t Len, uint8_t *Out); 51 52 // Changes U to contain only ASCII (isprint+isspace) characters. 53 // Returns true iff U has been changed. 54 bool ToASCII(Unit &U); 55 bool IsASCII(const Unit &U); 56 57 int NumberOfCpuCores(); 58 int GetPid(); 59 60 // Dictionary. 61 62 // Parses one dictionary entry. 63 // If successfull, write the enty to Unit and returns true, 64 // otherwise returns false. 65 bool ParseOneDictionaryEntry(const std::string &Str, Unit *U); 66 // Parses the dictionary file, fills Units, returns true iff all lines 67 // were parsed succesfully. 68 bool ParseDictionaryFile(const std::string &Text, std::vector<Unit> *Units); 69 70 class Fuzzer { 71 public: 72 struct FuzzingOptions { 73 int Verbosity = 1; 74 int MaxLen = 0; 75 int UnitTimeoutSec = 300; 76 int MaxTotalTimeSec = 0; 77 bool DoCrossOver = true; 78 int MutateDepth = 5; 79 bool ExitOnFirst = false; 80 bool UseCounters = false; 81 bool UseIndirCalls = true; 82 bool UseTraces = false; 83 bool UseFullCoverageSet = false; 84 bool Reload = true; 85 bool ShuffleAtStartUp = true; 86 int PreferSmallDuringInitialShuffle = -1; 87 size_t MaxNumberOfRuns = ULONG_MAX; 88 int SyncTimeout = 600; 89 int ReportSlowUnits = 10; 90 bool OnlyASCII = false; 91 int TBMDepth = 10; 92 int TBMWidth = 10; 93 std::string OutputCorpus; 94 std::string SyncCommand; 95 std::string ArtifactPrefix = "./"; 96 std::string ExactArtifactPath; 97 bool SaveArtifacts = true; 98 bool PrintNEW = true; // Print a status line when new units are found; 99 bool OutputCSV = false; 100 }; 101 Fuzzer(UserSuppliedFuzzer &USF, FuzzingOptions Options); 102 void AddToCorpus(const Unit &U) { Corpus.push_back(U); } 103 size_t ChooseUnitIdxToMutate(); 104 const Unit &ChooseUnitToMutate() { return Corpus[ChooseUnitIdxToMutate()]; }; 105 void Loop(); 106 void Drill(); 107 void ShuffleAndMinimize(); 108 void InitializeTraceState(); 109 size_t CorpusSize() const { return Corpus.size(); } 110 void ReadDir(const std::string &Path, long *Epoch) { 111 Printf("Loading corpus: %s\n", Path.c_str()); 112 ReadDirToVectorOfUnits(Path.c_str(), &Corpus, Epoch); 113 } 114 void RereadOutputCorpus(); 115 // Save the current corpus to OutputCorpus. 116 void SaveCorpus(); 117 118 size_t secondsSinceProcessStartUp() { 119 return duration_cast<seconds>(system_clock::now() - ProcessStartTime) 120 .count(); 121 } 122 123 size_t getTotalNumberOfRuns() { return TotalNumberOfRuns; } 124 125 static void StaticAlarmCallback(); 126 127 void ExecuteCallback(const Unit &U); 128 129 // Merge Corpora[1:] into Corpora[0]. 130 void Merge(const std::vector<std::string> &Corpora); 131 132 private: 133 void AlarmCallback(); 134 void MutateAndTestOne(); 135 void ReportNewCoverage(const Unit &U); 136 bool RunOne(const Unit &U); 137 void RunOneAndUpdateCorpus(Unit &U); 138 void WriteToOutputCorpus(const Unit &U); 139 void WriteUnitToFileWithPrefix(const Unit &U, const char *Prefix); 140 void PrintStats(const char *Where, const char *End = "\n"); 141 void PrintStatusForNewUnit(const Unit &U); 142 void PrintUnitInASCII(const Unit &U, const char *PrintAfter = ""); 143 144 void SyncCorpus(); 145 146 size_t RecordBlockCoverage(); 147 size_t RecordCallerCalleeCoverage(); 148 void PrepareCoverageBeforeRun(); 149 bool CheckCoverageAfterRun(); 150 151 152 // Trace-based fuzzing: we run a unit with some kind of tracing 153 // enabled and record potentially useful mutations. Then 154 // We apply these mutations one by one to the unit and run it again. 155 156 // Start tracing; forget all previously proposed mutations. 157 void StartTraceRecording(); 158 // Stop tracing and return the number of proposed mutations. 159 size_t StopTraceRecording(); 160 // Apply Idx-th trace-based mutation to U. 161 void ApplyTraceBasedMutation(size_t Idx, Unit *U); 162 163 void SetDeathCallback(); 164 static void StaticDeathCallback(); 165 void DeathCallback(); 166 Unit CurrentUnit; 167 168 size_t TotalNumberOfRuns = 0; 169 size_t TotalNumberOfExecutedTraceBasedMutations = 0; 170 171 std::vector<Unit> Corpus; 172 std::unordered_set<std::string> UnitHashesAddedToCorpus; 173 174 // For UseCounters 175 std::vector<uint8_t> CounterBitmap; 176 size_t TotalBits() { // Slow. Call it only for printing stats. 177 size_t Res = 0; 178 for (auto x : CounterBitmap) Res += __builtin_popcount(x); 179 return Res; 180 } 181 182 UserSuppliedFuzzer &USF; 183 FuzzingOptions Options; 184 system_clock::time_point ProcessStartTime = system_clock::now(); 185 system_clock::time_point LastExternalSync = system_clock::now(); 186 system_clock::time_point UnitStartTime; 187 long TimeOfLongestUnitInSeconds = 0; 188 long EpochOfLastReadOfOutputCorpus = 0; 189 size_t LastRecordedBlockCoverage = 0; 190 size_t LastRecordedCallerCalleeCoverage = 0; 191 }; 192 193 class SimpleUserSuppliedFuzzer: public UserSuppliedFuzzer { 194 public: 195 SimpleUserSuppliedFuzzer(FuzzerRandomBase *Rand, UserCallback Callback) 196 : UserSuppliedFuzzer(Rand), Callback(Callback) {} 197 198 virtual int TargetFunction(const uint8_t *Data, size_t Size) override { 199 return Callback(Data, Size); 200 } 201 202 private: 203 UserCallback Callback = nullptr; 204 }; 205 206 }; // namespace fuzzer 207 208 #endif // LLVM_FUZZER_INTERNAL_H 209
