summaryrefslogtreecommitdiffstats
path: root/lib/Fuzzer/FuzzerDriver.cpp
blob: 9ccd744c28dc02135f006ab4b522213a3a5a726a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
//===- FuzzerDriver.cpp - FuzzerDriver function and flags -----------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// FuzzerDriver and flag parsing.
//===----------------------------------------------------------------------===//

#include "FuzzerInterface.h"
#include "FuzzerInternal.h"

#include <cstring>
#include <unistd.h>
#include <iostream>
#include <thread>
#include <atomic>
#include <mutex>

namespace fuzzer {

// Program arguments.
struct FlagDescription {
  const char *Name;
  const char *Description;
  int   Default;
  int   *Flag;
};

struct {
#define FUZZER_FLAG(Type, Name, Default, Description) Type Name;
#include "FuzzerFlags.def"
#undef FUZZER_FLAG
} Flags;

static FlagDescription FlagDescriptions [] {
#define FUZZER_FLAG(Type, Name, Default, Description) {#Name, Description, Default, &Flags.Name},
#include "FuzzerFlags.def"
#undef FUZZER_FLAG
};

static const size_t kNumFlags =
    sizeof(FlagDescriptions) / sizeof(FlagDescriptions[0]);

static std::vector<std::string> inputs;
static const char *ProgName;

static void PrintHelp() {
  std::cerr << "Usage: " << ProgName
            << " [-flag1=val1 [-flag2=val2 ...] ] [dir1 [dir2 ...] ]\n";
  std::cerr << "\nFlags: (strictly in form -flag=value)\n";
  size_t MaxFlagLen = 0;
  for (size_t F = 0; F < kNumFlags; F++)
    MaxFlagLen = std::max(strlen(FlagDescriptions[F].Name), MaxFlagLen);

  for (size_t F = 0; F < kNumFlags; F++) {
    const auto &D = FlagDescriptions[F];
    std::cerr << "  " << D.Name;
    for (size_t i = 0, n = MaxFlagLen - strlen(D.Name); i < n; i++)
      std::cerr << " ";
    std::cerr << "\t";
    std::cerr << D.Default << "\t" << D.Description << "\n";
  }
}

static const char *FlagValue(const char *Param, const char *Name) {
  size_t Len = strlen(Name);
  if (Param[0] == '-' && strstr(Param + 1, Name) == Param + 1 &&
      Param[Len + 1] == '=')
      return &Param[Len + 2];
  return nullptr;
}

static bool ParseOneFlag(const char *Param) {
  if (Param[0] != '-') return false;
  for (size_t F = 0; F < kNumFlags; F++) {
    const char *Name = FlagDescriptions[F].Name;
    const char *Str = FlagValue(Param, Name);
    if (Str)  {
      int Val = std::stol(Str);
      *FlagDescriptions[F].Flag = Val;
      if (Flags.verbosity >= 2)
        std::cerr << "Flag: " << Name << " " << Val << "\n";
      return true;
    }
  }
  PrintHelp();
  exit(1);
}

// We don't use any library to minimize dependencies.
static void ParseFlags(int argc, char **argv) {
  for (size_t F = 0; F < kNumFlags; F++)
    *FlagDescriptions[F].Flag = FlagDescriptions[F].Default;
  for (int A = 1; A < argc; A++) {
    if (ParseOneFlag(argv[A])) continue;
    inputs.push_back(argv[A]);
  }
}

static void WorkerThread(const std::string &Cmd, std::atomic<int> *Counter,
                        int NumJobs, std::atomic<bool> *HasErrors) {
  static std::mutex CerrMutex;
  while (true) {
    int C = (*Counter)++;
    if (C >= NumJobs) break;
    std::string Log = "fuzz-" + std::to_string(C) + ".log";
    std::string ToRun = Cmd + " > " + Log + " 2>&1\n";
    if (Flags.verbosity)
      std::cerr << ToRun;
    int ExitCode = system(ToRun.c_str());
    if (ExitCode != 0)
      *HasErrors = true;
    std::lock_guard<std::mutex> Lock(CerrMutex);
    std::cerr << "================== Job " << C
              << " exited with exit code " << ExitCode
              << " =================\n";
    fuzzer::CopyFileToErr(Log);
  }
}

static int RunInMultipleProcesses(int argc, char **argv, int NumWorkers,
                                  int NumJobs) {
  std::atomic<int> Counter(0);
  std::atomic<bool> HasErrors(false);
  std::string Cmd;
  for (int i = 0; i < argc; i++) {
    if (FlagValue(argv[i], "jobs") || FlagValue(argv[i], "workers")) continue;
    Cmd += argv[i];
    Cmd += " ";
  }
  std::vector<std::thread> V;
  for (int i = 0; i < NumWorkers; i++)
    V.push_back(std::thread(WorkerThread, Cmd, &Counter, NumJobs, &HasErrors));
  for (auto &T : V)
    T.join();
  return HasErrors ? 1 : 0;
}

int FuzzerDriver(int argc, char **argv, UserCallback Callback) {
  using namespace fuzzer;

  ProgName = argv[0];
  ParseFlags(argc, argv);
  if (Flags.help) {
    PrintHelp();
    return 0;
  }

  if (Flags.workers > 0 && Flags.jobs > 0)
    return RunInMultipleProcesses(argc, argv, Flags.workers, Flags.jobs);

  Fuzzer::FuzzingOptions Options;
  Options.Verbosity = Flags.verbosity;
  Options.MaxLen = Flags.max_len;
  Options.DoCrossOver = Flags.cross_over;
  Options.MutateDepth = Flags.mutate_depth;
  Options.ExitOnFirst = Flags.exit_on_first;
  Options.UseCounters = Flags.use_counters;
  Options.UseFullCoverageSet = Flags.use_full_coverage_set;
  Options.UseCoveragePairs = Flags.use_coverage_pairs;
  Options.PreferSmallDuringInitialShuffle =
      Flags.prefer_small_during_initial_shuffle;
  if (Flags.runs >= 0)
    Options.MaxNumberOfRuns = Flags.runs;
  if (!inputs.empty())
    Options.OutputCorpus = inputs[0];
  Fuzzer F(Callback, Options);

  unsigned seed = Flags.seed;
  // Initialize seed.
  if (seed == 0)
    seed = time(0) * 10000 + getpid();
  if (Flags.verbosity)
    std::cerr << "Seed: " << seed << "\n";
  srand(seed);

  // Timer
  if (Flags.timeout > 0)
    SetTimer(Flags.timeout);

  for (auto &inp : inputs)
    F.ReadDir(inp);

  if (F.CorpusSize() == 0)
    F.AddToCorpus(Unit());  // Can't fuzz empty corpus, so add an empty input.
  F.ShuffleAndMinimize();
  if (Flags.save_minimized_corpus)
    F.SaveCorpus();
  F.Loop(Flags.iterations < 0 ? INT_MAX : Flags.iterations);
  if (Flags.verbosity)
    std::cerr << "Done " << F.getTotalNumberOfRuns()
              << " runs in " << F.secondsSinceProcessStartUp()
              << " seconds\n";
  return 0;
}

}  // namespace fuzzer