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
26namespace fuzzer {
27using namespace std::chrono;
28
29std::string FileToString(const std::string &Path);
30Unit FileToVector(const std::string &Path);
31void ReadDirToVectorOfUnits(const char *Path, std::vector<Unit> *V,
32                            long *Epoch);
33void WriteToFile(const Unit &U, const std::string &Path);
34void CopyFileToErr(const std::string &Path);
35// Returns "Dir/FileName" or equivalent for the current OS.
36std::string DirPlusFile(const std::string &DirPath,
37                        const std::string &FileName);
38
39void Printf(const char *Fmt, ...);
40void Print(const Unit &U, const char *PrintAfter = "");
41void PrintASCII(const Unit &U, const char *PrintAfter = "");
42std::string Hash(const Unit &U);
43void SetTimer(int Seconds);
44std::string Base64(const Unit &U);
45int ExecuteCommand(const std::string &Command);
46
47// Private copy of SHA1 implementation.
48static const int kSHA1NumBytes = 20;
49// Computes SHA1 hash of 'Len' bytes in 'Data', writes kSHA1NumBytes to 'Out'.
50void 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.
54bool ToASCII(Unit &U);
55bool IsASCII(const Unit &U);
56
57int NumberOfCpuCores();
58int 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.
65bool ParseOneDictionaryEntry(const std::string &Str, Unit *U);
66// Parses the dictionary file, fills Units, returns true iff all lines
67// were parsed succesfully.
68bool ParseDictionaryFile(const std::string &Text, std::vector<Unit> *Units);
69
70class 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
193class 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