1# Fuzzer for libaaudioservice 2 3## Plugin Design Considerations 4The fuzzer plugin for libaaudioservice is designed based on the 5understanding of the service and tries to achieve the following: 6 7##### Maximize code coverage 8The configuration parameters are not hardcoded, but instead selected based on 9incoming data. This ensures more code paths are reached by the fuzzer. 10 11AAudio Service request contains the following parameters: 121. AAudioFormat 132. UserId 143. ProcessId 154. InService 165. DeviceId 176. SampleRate 187. ChannelMask 198. Direction 209. SharingMode 2110. Usage 2211. ContentType 2312. InputPreset 2413. BufferCapacity 25 26| Parameter | Valid Input Values| Configured Value| 27|---------------------------|-------------| ----- | 28| `Format` | `AAUDIO_FORMAT_UNSPECIFIED`, `AAUDIO_FORMAT_PCM_I16`, `AAUDIO_FORMAT_PCM_FLOAT`, `AAUDIO_FORMAT_IEC61937`, `AAUDIO_FORMAT_PCM_I24_PACKED`, `AAUDIO_FORMAT_PCM_I32` | Value chosen from valid values by obtaining index from FuzzedDataProvider | 29| `UserId` | `INT32_MIN` to `INT32_MAX` | Value obtained from getuid() | 30| `ProcessId` | `INT32_MIN` to `INT32_MAX` | Value obtained from getpid() | 31| `InService` | `bool` | Value obtained from FuzzedDataProvider | 32| `DeviceId` | `INT32_MIN` to `INT32_MAX` | Value obtained from FuzzedDataProvider | 33| `SampleRate` | `INT32_MIN` to `INT32_MAX` | Value obtained from FuzzedDataProvider | 34| `ChannelMask` | `AAUDIO_UNSPECIFIED`, `AAUDIO_CHANNEL_INDEX_MASK_1`, `AAUDIO_CHANNEL_INDEX_MASK_2`, `AAUDIO_CHANNEL_INDEX_MASK_3`, `AAUDIO_CHANNEL_INDEX_MASK_4`, `AAUDIO_CHANNEL_INDEX_MASK_5`, `AAUDIO_CHANNEL_INDEX_MASK_6`, `AAUDIO_CHANNEL_INDEX_MASK_7`, `AAUDIO_CHANNEL_INDEX_MASK_8`, `AAUDIO_CHANNEL_INDEX_MASK_9`, `AAUDIO_CHANNEL_INDEX_MASK_10`, `AAUDIO_CHANNEL_INDEX_MASK_11`, `AAUDIO_CHANNEL_INDEX_MASK_12`, `AAUDIO_CHANNEL_INDEX_MASK_13`, `AAUDIO_CHANNEL_INDEX_MASK_14`, `AAUDIO_CHANNEL_INDEX_MASK_15`, `AAUDIO_CHANNEL_INDEX_MASK_16`, `AAUDIO_CHANNEL_INDEX_MASK_17`, `AAUDIO_CHANNEL_INDEX_MASK_18`, `AAUDIO_CHANNEL_INDEX_MASK_19`, `AAUDIO_CHANNEL_INDEX_MASK_20`, `AAUDIO_CHANNEL_INDEX_MASK_21`, `AAUDIO_CHANNEL_INDEX_MASK_22`, `AAUDIO_CHANNEL_INDEX_MASK_23`, `AAUDIO_CHANNEL_INDEX_MASK_24`, `AAUDIO_CHANNEL_MONO`, `AAUDIO_CHANNEL_STEREO`, `AAUDIO_CHANNEL_FRONT_BACK`, `AAUDIO_CHANNEL_2POINT0POINT2`, `AAUDIO_CHANNEL_2POINT1POINT2`, `AAUDIO_CHANNEL_3POINT0POINT2`, `AAUDIO_CHANNEL_3POINT1POINT2`, `AAUDIO_CHANNEL_5POINT1`, `AAUDIO_CHANNEL_MONO`, `AAUDIO_CHANNEL_STEREO`, `AAUDIO_CHANNEL_2POINT1`, `AAUDIO_CHANNEL_TRI`, `AAUDIO_CHANNEL_TRI_BACK`, `AAUDIO_CHANNEL_3POINT1`, `AAUDIO_CHANNEL_2POINT0POINT2`, `AAUDIO_CHANNEL_2POINT1POINT2`, `AAUDIO_CHANNEL_3POINT0POINT2`, `AAUDIO_CHANNEL_3POINT1POINT2`, `AAUDIO_CHANNEL_QUAD`, `AAUDIO_CHANNEL_QUAD_SIDE`, `AAUDIO_CHANNEL_SURROUND`, `AAUDIO_CHANNEL_PENTA`, `AAUDIO_CHANNEL_5POINT1`, `AAUDIO_CHANNEL_5POINT1_SIDE`, `AAUDIO_CHANNEL_5POINT1POINT2`, `AAUDIO_CHANNEL_5POINT1POINT4`, `AAUDIO_CHANNEL_6POINT1`, `AAUDIO_CHANNEL_7POINT1`, `AAUDIO_CHANNEL_7POINT1POINT2`, `AAUDIO_CHANNEL_7POINT1POINT4`, `AAUDIO_CHANNEL_9POINT1POINT4`, `AAUDIO_CHANNEL_9POINT1POINT6` | Value obtained from FuzzedDataProvider | 35| `Direction` | `AAUDIO_DIRECTION_OUTPUT`, `AAUDIO_DIRECTION_INPUT` | Value chosen from valid values by obtaining index from FuzzedDataProvider | 36| `SharingMode` | `AAUDIO_SHARING_MODE_EXCLUSIVE`, `AAUDIO_SHARING_MODE_SHARED` | Value chosen from valid values by obtaining index from FuzzedDataProvider | 37| `Usage` | `AAUDIO_USAGE_MEDIA`, `AAUDIO_USAGE_VOICE_COMMUNICATION`, `AAUDIO_USAGE_VOICE_COMMUNICATION_SIGNALLING`, `AAUDIO_USAGE_ALARM`, `AAUDIO_USAGE_NOTIFICATION`, `AAUDIO_USAGE_NOTIFICATION_RINGTONE`, `AAUDIO_USAGE_NOTIFICATION_EVENT`, `AAUDIO_USAGE_ASSISTANCE_ACCESSIBILITY`, `AAUDIO_USAGE_ASSISTANCE_NAVIGATION_GUIDANCE`, `AAUDIO_USAGE_ASSISTANCE_SONIFICATION`, `AAUDIO_USAGE_GAME`, `AAUDIO_USAGE_ASSISTANT`, `AAUDIO_SYSTEM_USAGE_EMERGENCY`, `AAUDIO_SYSTEM_USAGE_SAFETY`, `AAUDIO_SYSTEM_USAGE_VEHICLE_STATUS`, `AAUDIO_SYSTEM_USAGE_ANNOUNCEMENT` | Value chosen from valid values by obtaining index from FuzzedDataProvider | 38| `ContentType` | `AAUDIO_CONTENT_TYPE_SPEECH`, `AAUDIO_CONTENT_TYPE_MUSIC`, `AAUDIO_CONTENT_TYPE_MOVIE`, `AAUDIO_CONTENT_TYPE_SONIFICATION` | Value chosen from valid values by obtaining index from FuzzedDataProvider | 39| `InputPreset` | `AAUDIO_INPUT_PRESET_GENERIC`, `AAUDIO_INPUT_PRESET_CAMCORDER`, `AAUDIO_INPUT_PRESET_VOICE_RECOGNITION`, `AAUDIO_INPUT_PRESET_VOICE_COMMUNICATION`, `AAUDIO_INPUT_PRESET_UNPROCESSED`, `AAUDIO_INPUT_PRESET_VOICE_PERFORMANCE` | Value chosen from valid values by obtaining index from FuzzedDataProvider | 40| `BufferCapacity` | `INT32_MIN` to `INT32_MAX` | Value obtained from FuzzedDataProvider | 41| `HardwareSampleRate` | `INT32_MIN` to `INT32_MAX` | Value obtained from FuzzedDataProvider | 42| `HardwareSamplesPerFrame` | `INT32_MIN` to `INT32_MAX` | Value obtained from FuzzedDataProvider | 43| `HardwareFormat` | `AAUDIO_FORMAT_UNSPECIFIED`, `AAUDIO_FORMAT_PCM_I16`, `AAUDIO_FORMAT_PCM_FLOAT`, `AAUDIO_FORMAT_IEC61937`, `AAUDIO_FORMAT_PCM_I24_PACKED`, `AAUDIO_FORMAT_PCM_I32` | Value chosen from valid values by obtaining index from FuzzedDataProvider | 44 45This also ensures that the plugin is always deterministic for any given input. 46 47## Build 48 49This describes steps to build oboeservice_fuzzer binary. 50 51### Android 52 53#### Steps to build 54Build the fuzzer 55``` 56 $ mm -j$(nproc) oboeservice_fuzzer 57``` 58 59#### Steps to run 60To run on device 61``` 62 $ adb sync data 63 $ adb shell /data/fuzz/arm64/oboeservice_fuzzer/oboeservice_fuzzer 64``` 65 66## References: 67 * http://llvm.org/docs/LibFuzzer.html 68 * https://github.com/google/oss-fuzz 69