tools/fuzzing/libfuzzer/FuzzerInternal.h

   1 //===- FuzzerInternal.h - Internal header for the Fuzzer --------*- C++ -* ===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 // Define the main class fuzzer::Fuzzer and most functions.
   9 //===----------------------------------------------------------------------===//
  10
  11 #ifndef LLVM_FUZZER_INTERNAL_H
  12 #define LLVM_FUZZER_INTERNAL_H
  13
  14 #include "FuzzerDataFlowTrace.h"
  15 #include "FuzzerDefs.h"
  16 #include "FuzzerExtFunctions.h"
  17 #include "FuzzerInterface.h"
  18 #include "FuzzerOptions.h"
  19 #include "FuzzerSHA1.h"
  20 #include "FuzzerValueBitMap.h"
  21 #include <algorithm>
  22 #include <atomic>
  23 #include <chrono>
  24 #include <climits>
  25 #include <cstdlib>
  26 #include <string.h>
  27
  28 namespace fuzzer {
  29
  30 using namespace std::chrono;
  31
  32 class Fuzzer {
  33 public:
  34
  35   Fuzzer(UserCallback CB, InputCorpus &Corpus, MutationDispatcher &MD,
  36          FuzzingOptions Options);
  37   ~Fuzzer();
  38   int Loop(Vector<SizedFile> &CorporaFiles);
  39   int ReadAndExecuteSeedCorpora(Vector<SizedFile> &CorporaFiles);
  40   void MinimizeCrashLoop(const Unit &U);
  41   void RereadOutputCorpus(size_t MaxSize);
  42
  43   size_t secondsSinceProcessStartUp() {
  44     return duration_cast<seconds>(system_clock::now() - ProcessStartTime)
  45         .count();
  46   }
  47
  48   bool TimedOut() {
  49     return Options.MaxTotalTimeSec > 0 &&
  50            secondsSinceProcessStartUp() >
  51                static_cast<size_t>(Options.MaxTotalTimeSec);
  52   }
  53
  54   size_t execPerSec() {
  55     size_t Seconds = secondsSinceProcessStartUp();
  56     return Seconds ? TotalNumberOfRuns / Seconds : 0;
  57   }
  58
  59   size_t getTotalNumberOfRuns() { return TotalNumberOfRuns; }
  60
  61   static void StaticAlarmCallback();
  62   static void StaticCrashSignalCallback();
  63   static void StaticExitCallback();
  64   static void StaticInterruptCallback();
  65   static void StaticFileSizeExceedCallback();
  66   static void StaticGracefulExitCallback();
  67
  68   static void GracefullyExit();
  69   static bool isGracefulExitRequested();
  70
  71   int ExecuteCallback(const uint8_t *Data, size_t Size);
  72   bool RunOne(const uint8_t *Data, size_t Size, bool MayDeleteFile = false,
  73               InputInfo *II = nullptr, bool *FoundUniqFeatures = nullptr);
  74
  75   // Merge Corpora[1:] into Corpora[0].
  76   void Merge(const Vector<std::string> &Corpora);
  77   int CrashResistantMergeInternalStep(const std::string &ControlFilePath);
  78   MutationDispatcher &GetMD() { return MD; }
  79   void PrintFinalStats();
  80   void SetMaxInputLen(size_t MaxInputLen);
  81   void SetMaxMutationLen(size_t MaxMutationLen);
  82   void RssLimitCallback();
  83
  84   bool InFuzzingThread() const { return IsMyThread; }
  85   size_t GetCurrentUnitInFuzzingThead(const uint8_t **Data) const;
  86   void TryDetectingAMemoryLeak(const uint8_t *Data, size_t Size,
  87                                bool DuringInitialCorpusExecution);
  88
  89   void HandleMalloc(size_t Size);
  90   static bool MaybeExitGracefully();
  91   std::string WriteToOutputCorpus(const Unit &U);
  92
  93 private:
  94   void AlarmCallback();
  95   void CrashCallback();
  96   void ExitCallback();
  97   void CrashOnOverwrittenData();
  98   void InterruptCallback();
  99   bool MutateAndTestOne();
 100   void PurgeAllocator();
 101   void ReportNewCoverage(InputInfo *II, const Unit &U);
 102   void PrintPulseAndReportSlowInput(const uint8_t *Data, size_t Size);
 103   void WriteUnitToFileWithPrefix(const Unit &U, const char *Prefix);
 104   void PrintStats(const char *Where, const char *End = "\n", size_t Units = 0,
 105                   size_t Features = 0);
 106   void PrintStatusForNewUnit(const Unit &U, const char *Text);
 107   void CheckExitOnSrcPosOrItem();
 108
 109   static void StaticDeathCallback();
 110   void DumpCurrentUnit(const char *Prefix);
 111   void DeathCallback();
 112
 113   void AllocateCurrentUnitData();
 114   uint8_t *CurrentUnitData = nullptr;
 115   std::atomic<size_t> CurrentUnitSize;
 116   uint8_t BaseSha1[kSHA1NumBytes];  // Checksum of the base unit.
 117
 118   bool GracefulExitRequested = false;
 119
 120   size_t TotalNumberOfRuns = 0;
 121   size_t NumberOfNewUnitsAdded = 0;
 122
 123   size_t LastCorpusUpdateRun = 0;
 124
 125   bool HasMoreMallocsThanFrees = false;
 126   size_t NumberOfLeakDetectionAttempts = 0;
 127
 128   system_clock::time_point LastAllocatorPurgeAttemptTime = system_clock::now();
 129
 130   UserCallback CB;
 131   InputCorpus &Corpus;
 132   MutationDispatcher &MD;
 133   FuzzingOptions Options;
 134   DataFlowTrace DFT;
 135
 136   system_clock::time_point ProcessStartTime = system_clock::now();
 137   system_clock::time_point UnitStartTime, UnitStopTime;
 138   long TimeOfLongestUnitInSeconds = 0;
 139   long EpochOfLastReadOfOutputCorpus = 0;
 140
 141   size_t MaxInputLen = 0;
 142   size_t MaxMutationLen = 0;
 143   size_t TmpMaxMutationLen = 0;
 144
 145   Vector<uint32_t> UniqFeatureSetTmp;
 146
 147   // Need to know our own thread.
 148   static thread_local bool IsMyThread;
 149 };
 150
 151 struct ScopedEnableMsanInterceptorChecks {
 152   ScopedEnableMsanInterceptorChecks() {
 153     if (EF->__msan_scoped_enable_interceptor_checks)
 154       EF->__msan_scoped_enable_interceptor_checks();
 155   }
 156   ~ScopedEnableMsanInterceptorChecks() {
 157     if (EF->__msan_scoped_disable_interceptor_checks)
 158       EF->__msan_scoped_disable_interceptor_checks();
 159   }
 160 };
 161
 162 struct ScopedDisableMsanInterceptorChecks {
 163   ScopedDisableMsanInterceptorChecks() {
 164     if (EF->__msan_scoped_disable_interceptor_checks)
 165       EF->__msan_scoped_disable_interceptor_checks();
 166   }
 167   ~ScopedDisableMsanInterceptorChecks() {
 168     if (EF->__msan_scoped_enable_interceptor_checks)
 169       EF->__msan_scoped_enable_interceptor_checks();
 170   }
 171 };
 172
 173 } // namespace fuzzer
 174
 175 #endif // LLVM_FUZZER_INTERNAL_H