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 "FuzzerDataFlowTrace.h"
16 #include "FuzzerDefs.h"
17 #include "FuzzerExtFunctions.h"
18 #include "FuzzerInterface.h"
19 #include "FuzzerOptions.h"
20 #include "FuzzerSHA1.h"
21 #include "FuzzerValueBitMap.h"
22 #include <algorithm>
23 #include <atomic>
24 #include <chrono>
25 #include <climits>
26 #include <cstdlib>
27 #include <string.h>
28 
29 namespace fuzzer {
30 
31 using namespace std::chrono;
32 
33 class Fuzzer {
34 public:
35 
36   Fuzzer(UserCallback CB, InputCorpus &Corpus, MutationDispatcher &MD,
37          FuzzingOptions Options);
38   ~Fuzzer();
39   void Loop(const Vector<std::string> &CorpusDirs);
40   void ReadAndExecuteSeedCorpora(const Vector<std::string> &CorpusDirs);
41   void MinimizeCrashLoop(const Unit &U);
42   void RereadOutputCorpus(size_t MaxSize);
43 
secondsSinceProcessStartUp()44   size_t secondsSinceProcessStartUp() {
45     return duration_cast<seconds>(system_clock::now() - ProcessStartTime)
46         .count();
47   }
48 
TimedOut()49   bool TimedOut() {
50     return Options.MaxTotalTimeSec > 0 &&
51            secondsSinceProcessStartUp() >
52                static_cast<size_t>(Options.MaxTotalTimeSec);
53   }
54 
execPerSec()55   size_t execPerSec() {
56     size_t Seconds = secondsSinceProcessStartUp();
57     return Seconds ? TotalNumberOfRuns / Seconds : 0;
58   }
59 
getTotalNumberOfRuns()60   size_t getTotalNumberOfRuns() { return TotalNumberOfRuns; }
61 
62   static void StaticAlarmCallback();
63   static void StaticCrashSignalCallback();
64   static void StaticExitCallback();
65   static void StaticInterruptCallback();
66   static void StaticFileSizeExceedCallback();
67   static void StaticGracefulExitCallback();
68 
69   void ExecuteCallback(const uint8_t *Data, size_t Size);
70   bool RunOne(const uint8_t *Data, size_t Size, bool MayDeleteFile = false,
71               InputInfo *II = nullptr, bool *FoundUniqFeatures = nullptr);
72 
73   // Merge Corpora[1:] into Corpora[0].
74   void Merge(const Vector<std::string> &Corpora);
75   void CrashResistantMerge(const Vector<std::string> &Args,
76                            const Vector<std::string> &Corpora,
77                            const char *CoverageSummaryInputPathOrNull,
78                            const char *CoverageSummaryOutputPathOrNull,
79                            const char *MergeControlFilePathOrNull);
80   void CrashResistantMergeInternalStep(const std::string &ControlFilePath);
GetMD()81   MutationDispatcher &GetMD() { return MD; }
82   void PrintFinalStats();
83   void SetMaxInputLen(size_t MaxInputLen);
84   void SetMaxMutationLen(size_t MaxMutationLen);
85   void RssLimitCallback();
86 
InFuzzingThread()87   bool InFuzzingThread() const { return IsMyThread; }
88   size_t GetCurrentUnitInFuzzingThead(const uint8_t **Data) const;
89   void TryDetectingAMemoryLeak(const uint8_t *Data, size_t Size,
90                                bool DuringInitialCorpusExecution);
91 
92   void HandleMalloc(size_t Size);
93   void AnnounceOutput(const uint8_t *Data, size_t Size);
94 
95 private:
96   void AlarmCallback();
97   void CrashCallback();
98   void ExitCallback();
99   void MaybeExitGracefully();
100   void CrashOnOverwrittenData();
101   void InterruptCallback();
102   void MutateAndTestOne();
103   void PurgeAllocator();
104   void ReportNewCoverage(InputInfo *II, const Unit &U);
105   void PrintPulseAndReportSlowInput(const uint8_t *Data, size_t Size);
106   void WriteToOutputCorpus(const Unit &U);
107   void WriteUnitToFileWithPrefix(const Unit &U, const char *Prefix);
108   void PrintStats(const char *Where, const char *End = "\n", size_t Units = 0);
109   void PrintStatusForNewUnit(const Unit &U, const char *Text);
110   void CheckExitOnSrcPosOrItem();
111 
112   static void StaticDeathCallback();
113   void DumpCurrentUnit(const char *Prefix);
114   void DeathCallback();
115 
116   void AllocateCurrentUnitData();
117   uint8_t *CurrentUnitData = nullptr;
118   std::atomic<size_t> CurrentUnitSize;
119   uint8_t BaseSha1[kSHA1NumBytes];  // Checksum of the base unit.
120 
121   bool GracefulExitRequested = false;
122 
123   size_t TotalNumberOfRuns = 0;
124   size_t NumberOfNewUnitsAdded = 0;
125 
126   size_t LastCorpusUpdateRun = 0;
127 
128   bool HasMoreMallocsThanFrees = false;
129   size_t NumberOfLeakDetectionAttempts = 0;
130 
131   system_clock::time_point LastAllocatorPurgeAttemptTime = system_clock::now();
132 
133   UserCallback CB;
134   InputCorpus &Corpus;
135   MutationDispatcher &MD;
136   FuzzingOptions Options;
137   DataFlowTrace DFT;
138 
139   system_clock::time_point ProcessStartTime = system_clock::now();
140   system_clock::time_point UnitStartTime, UnitStopTime;
141   long TimeOfLongestUnitInSeconds = 0;
142   long EpochOfLastReadOfOutputCorpus = 0;
143 
144   size_t MaxInputLen = 0;
145   size_t MaxMutationLen = 0;
146   size_t TmpMaxMutationLen = 0;
147 
148   Vector<uint32_t> UniqFeatureSetTmp;
149 
150   // Need to know our own thread.
151   static thread_local bool IsMyThread;
152 };
153 
154 struct ScopedEnableMsanInterceptorChecks {
ScopedEnableMsanInterceptorChecksScopedEnableMsanInterceptorChecks155   ScopedEnableMsanInterceptorChecks() {
156     if (EF->__msan_scoped_enable_interceptor_checks)
157       EF->__msan_scoped_enable_interceptor_checks();
158   }
~ScopedEnableMsanInterceptorChecksScopedEnableMsanInterceptorChecks159   ~ScopedEnableMsanInterceptorChecks() {
160     if (EF->__msan_scoped_disable_interceptor_checks)
161       EF->__msan_scoped_disable_interceptor_checks();
162   }
163 };
164 
165 struct ScopedDisableMsanInterceptorChecks {
ScopedDisableMsanInterceptorChecksScopedDisableMsanInterceptorChecks166   ScopedDisableMsanInterceptorChecks() {
167     if (EF->__msan_scoped_disable_interceptor_checks)
168       EF->__msan_scoped_disable_interceptor_checks();
169   }
~ScopedDisableMsanInterceptorChecksScopedDisableMsanInterceptorChecks170   ~ScopedDisableMsanInterceptorChecks() {
171     if (EF->__msan_scoped_enable_interceptor_checks)
172       EF->__msan_scoped_enable_interceptor_checks();
173   }
174 };
175 
176 } // namespace fuzzer
177 
178 #endif // LLVM_FUZZER_INTERNAL_H
179