| /****************************************************************************** |
| * |
| * Copyright (C) 2020 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at: |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| * |
| ***************************************************************************** |
| * Originally developed and contributed by Ittiam Systems Pvt. Ltd, Bangalore |
| */ |
| #include <stdint.h> |
| #include <string.h> |
| #include "gsm.h" |
| |
| constexpr int16_t kGsmInFrameSize = 33; |
| constexpr int16_t kGsmInFrameSizeMinus1 = kGsmInFrameSize - 1; |
| constexpr int16_t kGsmOutFrameSize = 160; |
| constexpr int16_t kGsmTotalInFrameSize = (kGsmInFrameSize + kGsmInFrameSizeMinus1); |
| constexpr int16_t kGsmTotalOutFrameSize = (kGsmOutFrameSize * 2); |
| |
| class Codec { |
| public: |
| Codec() = default; |
| ~Codec() { deInitDecoder(); } |
| bool initDecoder(); |
| void decodeFrames(const uint8_t *data, size_t size); |
| void deInitDecoder(); |
| |
| private: |
| gsm mGsm = nullptr; |
| }; |
| |
| bool Codec::initDecoder() { |
| mGsm = gsm_create(); |
| if (mGsm) { |
| int msopt = 1; |
| gsm_option(mGsm, GSM_OPT_WAV49, &msopt); |
| return true; |
| } else { |
| return false; |
| } |
| } |
| |
| void Codec::decodeFrames(const uint8_t *data, size_t size) { |
| uint8_t firstByte = *data; |
| int32_t verbosity = firstByte & 0x01; |
| int32_t fast = (firstByte >> 1) & 0x01; |
| gsm_option(mGsm, GSM_OPT_VERBOSE, &verbosity); |
| gsm_option(mGsm, GSM_OPT_FAST, &fast); |
| gsm_byte *readPointer = const_cast<uint8_t *>(data); |
| uint8_t tmpData[kGsmTotalInFrameSize]; |
| gsm_signal out[kGsmTotalOutFrameSize]; |
| |
| while (size > 0) { |
| if (size < kGsmTotalInFrameSize) { |
| memset(tmpData, 0, sizeof(tmpData)); |
| memcpy(tmpData, data, size); |
| size = kGsmTotalInFrameSize; |
| readPointer = tmpData; |
| } |
| gsm_decode(mGsm, readPointer, out); |
| readPointer += kGsmInFrameSize; |
| size -= kGsmInFrameSize; |
| |
| gsm_decode(mGsm, readPointer, out); |
| readPointer += kGsmInFrameSizeMinus1; |
| size -= kGsmInFrameSizeMinus1; |
| } |
| } |
| |
| void Codec::deInitDecoder() { |
| gsm_destroy(mGsm); |
| mGsm = nullptr; |
| } |
| |
| extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) { |
| if (size < 1) { |
| return 0; |
| } |
| Codec *codec = new Codec(); |
| if (!codec) { |
| return 0; |
| } |
| if (codec->initDecoder()) { |
| codec->decodeFrames(data, size); |
| } |
| delete codec; |
| return 0; |
| } |