Added AudioProcessing fuzzer

webrtc/test/fuzzers/audio_processing_fuzzer.cc

Index: webrtc/test/fuzzers/audio_processing_fuzzer.cc
diff --git a/webrtc/test/fuzzers/audio_processing_fuzzer.cc b/webrtc/test/fuzzers/audio_processing_fuzzer.cc
new file mode 100644
index 0000000000000000000000000000000000000000..ef623f6bc7961461f1056439d7ffc2c756327688
--- /dev/null
+++ b/webrtc/test/fuzzers/audio_processing_fuzzer.cc
@@ -0,0 +1,157 @@
+/*
+ *  Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/test/fuzzers/audio_processing_fuzzer.h"
+
+#include <algorithm>
+#include <array>
+#include <cmath>
+
+#include "webrtc/base/checks.h"
+#include "webrtc/modules/audio_processing/include/audio_processing.h"
+#include "webrtc/modules/include/module_common_types.h"
+
+namespace webrtc {
+namespace {
+size_t ByteToNativeRate(uint8_t data) {
+  using Rate = AudioProcessing::NativeRate;
+  switch (data % 4) {
+    case 0:
+    // Breaks AEC3.
+    // return static_cast<size_t>(Rate::kSampleRate8kHz);
+    case 1:
+      return static_cast<size_t>(Rate::kSampleRate16kHz);
+    case 2:
+      return static_cast<size_t>(Rate::kSampleRate32kHz);
+    default:
+      return static_cast<size_t>(Rate::kSampleRate48kHz);
+  }
+}
+
+template <class T>
+bool ParseSequence(size_t size,
+                   const uint8_t** data,
+                   size_t* remaining_size,
+                   T* result_data) {
+  const size_t data_size_bytes = sizeof(T) * size;
+  if (data_size_bytes > *remaining_size) {
+    return false;
+  }
+
+  std::copy(*data, *data + data_size_bytes,
+            reinterpret_cast<uint8_t*>(result_data));
+
+  *data += data_size_bytes;
+  *remaining_size -= data_size_bytes;
+  return true;
+}
+
+void FuzzAudioProcessing(const uint8_t* data,
+                         size_t size,
+                         bool is_float,
+                         AudioProcessing* apm) {
+  AudioFrame fixed_frame;
+  std::array<float, 480> float_frame;
+  float* const first_channel = &float_frame[0];
+
+  while (size > 0) {
+    // Decide input/output rate for this iteration.
+    const auto input_rate_byte = ParseByte(&data, &size);
+    const auto output_rate_byte = ParseByte(&data, &size);
+    if (!input_rate_byte || !output_rate_byte) {
+      return;
+    }
+    const auto input_rate_hz = ByteToNativeRate(*input_rate_byte);
+    const auto output_rate_hz = ByteToNativeRate(*output_rate_byte);
+
+    const size_t samples_per_input_channel =
+        rtc::CheckedDivExact(input_rate_hz, 100ul);
+    fixed_frame.samples_per_channel_ = samples_per_input_channel;
+    fixed_frame.sample_rate_hz_ = input_rate_hz;
+
+    // Two channels breaks AEC3.
+    fixed_frame.num_channels_ = 1;
+
+    // Fill the arrays with audio samples from the data.
+    if (is_float) {
+      if (!ParseSequence(samples_per_input_channel, &data, &size,
+                         &float_frame[0])) {
+        return;
+      }
+    } else if (!ParseSequence(samples_per_input_channel, &data, &size,
+                              fixed_frame.mutable_data())) {
+      return;
+    }
+
+    // Filter obviously wrong values like inf/nan and values that will
+    // lead to inf/nan in calculations. 1e6 leads to DCHECKS failing.
+    for (auto& x : float_frame) {
+      if (!std::isnormal(x) || std::abs(x) > 1e5) {
+        x = 0;
+      }
+    }
+
+    // Make the APM call depending on capture/render mode and float /
+    // fix interface.
+    const auto is_capture = ParseBool(&data, &size);
+    if (!is_capture) {
+      return;
+    }
+    if (*is_capture) {
+      auto apm_return_code =
+          is_float ? (apm->ProcessStream(
+                         &first_channel, StreamConfig(input_rate_hz, 1),
+                         StreamConfig(output_rate_hz, 1), &first_channel))
+                   : (apm->ProcessStream(&fixed_frame));
+      RTC_DCHECK_EQ(apm_return_code, AudioProcessing::kNoError);

[hlundin-webrtc, 2017/06/20 09:32:58]

Hmmm. Will the live fuzzer be run with dcheck_always_on? And, what do we want
the fuzzer to check? I mean, in general it is rather expected that a function
returns an error when inserting fuzzed data. The problem you tried to get around
was that the fuzzer did nothing because of a setup problem. Can you instead
explicitly check that kBadDataLengthError is not returned?

[aleloi, 2017/06/20 09:46:42]

Done.

+    } else {
+      auto apm_return_code =
+          is_float ? (apm->ProcessReverseStream(
+                         &first_channel, StreamConfig(input_rate_hz, 1),
+                         StreamConfig(output_rate_hz, 1), &first_channel))
+                   : (apm->ProcessReverseStream(&fixed_frame));
+      RTC_DCHECK_EQ(apm_return_code, AudioProcessing::kNoError);

[hlundin-webrtc, 2017/06/20 09:32:58]

Same here.

[aleloi, 2017/06/20 09:46:42]

Done.

+    }
+  }
+}
+
+}  // namespace
+
+rtc::Optional<bool> ParseBool(const uint8_t** data, size_t* remaining_size) {
+  if (1 > *remaining_size) {
+    return rtc::Optional<bool>();
+  }
+  auto res = rtc::Optional<bool>((**data) % 2);
+  *data += 1;
+  *remaining_size -= 1;
+  return res;
+}
+
+rtc::Optional<uint8_t> ParseByte(const uint8_t** data, size_t* remaining_size) {
+  if (1 > *remaining_size) {
+    return rtc::Optional<uint8_t>();
+  }
+  auto res = rtc::Optional<uint8_t>((**data));
+  *data += 1;
+  *remaining_size -= 1;
+  return res;
+}
+
+void FuzzAudioProcessing(const uint8_t* data,
+                         size_t size,
+                         std::unique_ptr<AudioProcessing> apm) {
+  const auto is_float = ParseBool(&data, &size);
+  if (!is_float) {
+    return;
+  }
+
+  FuzzAudioProcessing(data, size, *is_float, apm.get());
+}
+}  // namespace webrtc