1 files changed, 325 insertions, 0 deletions
diff --git a/json4cpp/tests/thirdparty/Fuzzer/FuzzerTraceState.cpp b/json4cpp/tests/thirdparty/Fuzzer/FuzzerTraceState.cpp
new file mode 100644
index 0000000000..be62a6624b
--- /dev/null
+++ b/json4cpp/tests/thirdparty/Fuzzer/FuzzerTraceState.cpp
@@ -0,0 +1,325 @@
+//===- FuzzerTraceState.cpp - Trace-based fuzzer mutator ------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+// Data tracing.
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerDictionary.h"
+#include "FuzzerInternal.h"
+#include "FuzzerIO.h"
+#include "FuzzerMutate.h"
+#include "FuzzerRandom.h"
+#include "FuzzerTracePC.h"
+#include <algorithm>
+#include <cstring>
+#include <map>
+#include <set>
+#include <thread>
+
+namespace fuzzer {
+
+// For now, very simple: put Size bytes of Data at position Pos.
+struct TraceBasedMutation {
+  uint32_t Pos;
+  Word W;
+};
+
+// Declared as static globals for faster checks inside the hooks.
+static bool RecordingMemcmp = false;
+static bool RecordingMemmem = false;
+static bool DoingMyOwnMemmem = false;
+
+ScopedDoingMyOwnMemmem::ScopedDoingMyOwnMemmem() { DoingMyOwnMemmem = true; }
+ScopedDoingMyOwnMemmem::~ScopedDoingMyOwnMemmem() { DoingMyOwnMemmem = false; }
+
+class TraceState {
+public:
+  TraceState(MutationDispatcher &MD, const FuzzingOptions &Options,
+             const Fuzzer *F)
+      : MD(MD), Options(Options), F(F) {}
+
+  void TraceMemcmpCallback(size_t CmpSize, const uint8_t *Data1,
+                           const uint8_t *Data2);
+
+  void TraceSwitchCallback(uintptr_t PC, size_t ValSizeInBits, uint64_t Val,
+                           size_t NumCases, uint64_t *Cases);
+  int TryToAddDesiredData(uint64_t PresentData, uint64_t DesiredData,
+                          size_t DataSize);
+  int TryToAddDesiredData(const uint8_t *PresentData,
+                          const uint8_t *DesiredData, size_t DataSize);
+
+  void StartTraceRecording() {
+    if (!Options.UseMemcmp)
+      return;
+    RecordingMemcmp = Options.UseMemcmp;
+    RecordingMemmem = Options.UseMemmem;
+    NumMutations = 0;
+    InterestingWords.clear();
+    MD.ClearAutoDictionary();
+  }
+
+  void StopTraceRecording() {
+    if (!RecordingMemcmp)
+      return;
+    RecordingMemcmp = false;
+    for (size_t i = 0; i < NumMutations; i++) {
+      auto &M = Mutations[i];
+      if (Options.Verbosity >= 2) {
+        AutoDictUnitCounts[M.W]++;
+        AutoDictAdds++;
+        if ((AutoDictAdds & (AutoDictAdds - 1)) == 0) {
+          typedef std::pair<size_t, Word> CU;
+          std::vector<CU> CountedUnits;
+          for (auto &I : AutoDictUnitCounts)
+            CountedUnits.push_back(std::make_pair(I.second, I.first));
+          std::sort(CountedUnits.begin(), CountedUnits.end(),
+                    [](const CU &a, const CU &b) { return a.first > b.first; });
+          Printf("AutoDict:\n");
+          for (auto &I : CountedUnits) {
+            Printf("   %zd ", I.first);
+            PrintASCII(I.second.data(), I.second.size());
+            Printf("\n");
+          }
+        }
+      }
+      MD.AddWordToAutoDictionary({M.W, M.Pos});
+    }
+    for (auto &W : InterestingWords)
+      MD.AddWordToAutoDictionary({W});
+  }
+
+  void AddMutation(uint32_t Pos, uint32_t Size, const uint8_t *Data) {
+    if (NumMutations >= kMaxMutations) return;
+    auto &M = Mutations[NumMutations++];
+    M.Pos = Pos;
+    M.W.Set(Data, Size);
+  }
+
+  void AddMutation(uint32_t Pos, uint32_t Size, uint64_t Data) {
+    assert(Size <= sizeof(Data));
+    AddMutation(Pos, Size, reinterpret_cast<uint8_t*>(&Data));
+  }
+
+  void AddInterestingWord(const uint8_t *Data, size_t Size) {
+    if (!RecordingMemmem || !F->InFuzzingThread()) return;
+    if (Size <= 1) return;
+    Size = std::min(Size, Word::GetMaxSize());
+    Word W(Data, Size);
+    InterestingWords.insert(W);
+  }
+
+ private:
+  bool IsTwoByteData(uint64_t Data) {
+    int64_t Signed = static_cast<int64_t>(Data);
+    Signed >>= 16;
+    return Signed == 0 || Signed == -1L;
+  }
+
+  // We don't want to create too many trace-based mutations as it is both
+  // expensive and useless. So after some number of mutations is collected,
+  // start rejecting some of them. The more there are mutations the more we
+  // reject.
+  bool WantToHandleOneMoreMutation() {
+    const size_t FirstN = 64;
+    // Gladly handle first N mutations.
+    if (NumMutations <= FirstN) return true;
+    size_t Diff = NumMutations - FirstN;
+    size_t DiffLog = sizeof(long) * 8 - __builtin_clzl((long)Diff);
+    assert(DiffLog > 0 && DiffLog < 64);
+    bool WantThisOne = MD.GetRand()(1 << DiffLog) == 0;  // 1 out of DiffLog.
+    return WantThisOne;
+  }
+
+  static const size_t kMaxMutations = 1 << 16;
+  size_t NumMutations;
+  TraceBasedMutation Mutations[kMaxMutations];
+  // TODO: std::set is too inefficient, need to have a custom DS here.
+  std::set<Word> InterestingWords;
+  MutationDispatcher &MD;
+  const FuzzingOptions Options;
+  const Fuzzer *F;
+  std::map<Word, size_t> AutoDictUnitCounts;
+  size_t AutoDictAdds = 0;
+};
+
+int TraceState::TryToAddDesiredData(uint64_t PresentData, uint64_t DesiredData,
+                                    size_t DataSize) {
+  if (NumMutations >= kMaxMutations || !WantToHandleOneMoreMutation()) return 0;
+  ScopedDoingMyOwnMemmem scoped_doing_my_own_memmem;
+  const uint8_t *UnitData;
+  auto UnitSize = F->GetCurrentUnitInFuzzingThead(&UnitData);
+  int Res = 0;
+  const uint8_t *Beg = UnitData;
+  const uint8_t *End = Beg + UnitSize;
+  for (const uint8_t *Cur = Beg; Cur < End; Cur++) {
+    Cur = (uint8_t *)SearchMemory(Cur, End - Cur, &PresentData, DataSize);
+    if (!Cur)
+      break;
+    size_t Pos = Cur - Beg;
+    assert(Pos < UnitSize);
+    AddMutation(Pos, DataSize, DesiredData);
+    AddMutation(Pos, DataSize, DesiredData + 1);
+    AddMutation(Pos, DataSize, DesiredData - 1);
+    Res++;
+  }
+  return Res;
+}
+
+int TraceState::TryToAddDesiredData(const uint8_t *PresentData,
+                                    const uint8_t *DesiredData,
+                                    size_t DataSize) {
+  if (NumMutations >= kMaxMutations || !WantToHandleOneMoreMutation()) return 0;
+  ScopedDoingMyOwnMemmem scoped_doing_my_own_memmem;
+  const uint8_t *UnitData;
+  auto UnitSize = F->GetCurrentUnitInFuzzingThead(&UnitData);
+  int Res = 0;
+  const uint8_t *Beg = UnitData;
+  const uint8_t *End = Beg + UnitSize;
+  for (const uint8_t *Cur = Beg; Cur < End; Cur++) {
+    Cur = (uint8_t *)SearchMemory(Cur, End - Cur, PresentData, DataSize);
+    if (!Cur)
+      break;
+    size_t Pos = Cur - Beg;
+    assert(Pos < UnitSize);
+    AddMutation(Pos, DataSize, DesiredData);
+    Res++;
+  }
+  return Res;
+}
+
+void TraceState::TraceMemcmpCallback(size_t CmpSize, const uint8_t *Data1,
+                                     const uint8_t *Data2) {
+  if (!RecordingMemcmp || !F->InFuzzingThread()) return;
+  CmpSize = std::min(CmpSize, Word::GetMaxSize());
+  int Added2 = TryToAddDesiredData(Data1, Data2, CmpSize);
+  int Added1 = TryToAddDesiredData(Data2, Data1, CmpSize);
+  if ((Added1 || Added2) && Options.Verbosity >= 3) {
+    Printf("MemCmp Added %d%d: ", Added1, Added2);
+    if (Added1) PrintASCII(Data1, CmpSize);
+    if (Added2) PrintASCII(Data2, CmpSize);
+    Printf("\n");
+  }
+}
+
+void TraceState::TraceSwitchCallback(uintptr_t PC, size_t ValSizeInBits,
+                                     uint64_t Val, size_t NumCases,
+                                     uint64_t *Cases) {
+  if (F->InFuzzingThread()) return;
+  size_t ValSize = ValSizeInBits / 8;
+  bool TryShort = IsTwoByteData(Val);
+  for (size_t i = 0; i < NumCases; i++)
+    TryShort &= IsTwoByteData(Cases[i]);
+
+  if (Options.Verbosity >= 3)
+    Printf("TraceSwitch: %p %zd # %zd; TryShort %d\n", PC, Val, NumCases,
+           TryShort);
+
+  for (size_t i = 0; i < NumCases; i++) {
+    TryToAddDesiredData(Val, Cases[i], ValSize);
+    if (TryShort)
+      TryToAddDesiredData(Val, Cases[i], 2);
+  }
+}
+
+static TraceState *TS;
+
+void Fuzzer::StartTraceRecording() {
+  if (!TS) return;
+  TS->StartTraceRecording();
+}
+
+void Fuzzer::StopTraceRecording() {
+  if (!TS) return;
+  TS->StopTraceRecording();
+}
+
+void Fuzzer::InitializeTraceState() {
+  if (!Options.UseMemcmp) return;
+  TS = new TraceState(MD, Options, this);
+}
+
+static size_t InternalStrnlen(const char *S, size_t MaxLen) {
+  size_t Len = 0;
+  for (; Len < MaxLen && S[Len]; Len++) {}
+  return Len;
+}
+
+}  // namespace fuzzer
+
+using fuzzer::TS;
+using fuzzer::RecordingMemcmp;
+
+extern "C" {
+
+// We may need to avoid defining weak hooks to stay compatible with older clang.
+#ifndef LLVM_FUZZER_DEFINES_SANITIZER_WEAK_HOOOKS
+# define LLVM_FUZZER_DEFINES_SANITIZER_WEAK_HOOOKS 1
+#endif
+
+#if LLVM_FUZZER_DEFINES_SANITIZER_WEAK_HOOOKS
+void __sanitizer_weak_hook_memcmp(void *caller_pc, const void *s1,
+                                  const void *s2, size_t n, int result) {
+  fuzzer::TPC.AddValueForMemcmp(caller_pc, s1, s2, n);
+  if (!RecordingMemcmp) return;
+  if (result == 0) return;  // No reason to mutate.
+  if (n <= 1) return;  // Not interesting.
+  TS->TraceMemcmpCallback(n, reinterpret_cast<const uint8_t *>(s1),
+                          reinterpret_cast<const uint8_t *>(s2));
+}
+
+void __sanitizer_weak_hook_strncmp(void *caller_pc, const char *s1,
+                                   const char *s2, size_t n, int result) {
+  fuzzer::TPC.AddValueForStrcmp(caller_pc, s1, s2, n);
+  if (!RecordingMemcmp) return;
+  if (result == 0) return;  // No reason to mutate.
+  size_t Len1 = fuzzer::InternalStrnlen(s1, n);
+  size_t Len2 = fuzzer::InternalStrnlen(s2, n);
+  n = std::min(n, Len1);
+  n = std::min(n, Len2);
+  if (n <= 1) return;  // Not interesting.
+  TS->TraceMemcmpCallback(n, reinterpret_cast<const uint8_t *>(s1),
+                          reinterpret_cast<const uint8_t *>(s2));
+}
+
+void __sanitizer_weak_hook_strcmp(void *caller_pc, const char *s1,
+                                   const char *s2, int result) {
+  fuzzer::TPC.AddValueForStrcmp(caller_pc, s1, s2, 64);
+  if (!RecordingMemcmp) return;
+  if (result == 0) return;  // No reason to mutate.
+  size_t Len1 = strlen(s1);
+  size_t Len2 = strlen(s2);
+  size_t N = std::min(Len1, Len2);
+  if (N <= 1) return;  // Not interesting.
+  TS->TraceMemcmpCallback(N, reinterpret_cast<const uint8_t *>(s1),
+                          reinterpret_cast<const uint8_t *>(s2));
+}
+
+void __sanitizer_weak_hook_strncasecmp(void *called_pc, const char *s1,
+                                       const char *s2, size_t n, int result) {
+  return __sanitizer_weak_hook_strncmp(called_pc, s1, s2, n, result);
+}
+void __sanitizer_weak_hook_strcasecmp(void *called_pc, const char *s1,
+                                      const char *s2, int result) {
+  return __sanitizer_weak_hook_strcmp(called_pc, s1, s2, result);
+}
+void __sanitizer_weak_hook_strstr(void *called_pc, const char *s1,
+                                  const char *s2, char *result) {
+  TS->AddInterestingWord(reinterpret_cast<const uint8_t *>(s2), strlen(s2));
+}
+void __sanitizer_weak_hook_strcasestr(void *called_pc, const char *s1,
+                                      const char *s2, char *result) {
+  TS->AddInterestingWord(reinterpret_cast<const uint8_t *>(s2), strlen(s2));
+}
+void __sanitizer_weak_hook_memmem(void *called_pc, const void *s1, size_t len1,
+                                  const void *s2, size_t len2, void *result) {
+  if (fuzzer::DoingMyOwnMemmem) return;
+  TS->AddInterestingWord(reinterpret_cast<const uint8_t *>(s2), len2);
+}
+
+#endif  // LLVM_FUZZER_DEFINES_SANITIZER_WEAK_HOOOKS
+}  // extern "C"