# Fuzzer for libkeystore
## Table of contents
+ [libkeystore-get-wifi-hidl](#libkeystore-get-wifi-hidl)
+ [libkeystore_attestation_application_id](#libkeystore_attestation_application_id)
# Fuzzer for libkeystore-get-wifi-hidl
## Plugin Design Considerations
The fuzzer plugin for libkeystore-get-wifi-hidl is designed based on the understanding of the library and tries to achieve the following:
##### Maximize code coverage
The configuration parameters are not hardcoded, but instead selected based on
incoming data. This ensures more code paths are reached by the fuzzer.
libkeystore-get-wifi-hidl supports the following parameters:
1. Key (parameter name: `key`)
| Parameter| Valid Values| Configured Value|
|------------- |-------------| ----- |
| `key` | `String` | Value obtained from FuzzedDataProvider|
This also ensures that the plugin is always deterministic for any given input.
##### Maximize utilization of input data
The plugin feeds the entire input data to the libkeystore-get-wifi-hidl module.
This ensures that the plugin tolerates any kind of input (empty, huge,
malformed, etc) and doesnt `exit()` on any input and thereby increasing the
chance of identifying vulnerabilities.
## Build
This describes steps to build keystoreGetWifiHidl_fuzzer binary.
### Android
#### Steps to build
Build the fuzzer
```
$ mm -j$(nproc) keystoreGetWifiHidl_fuzzer
```
#### Steps to run
To run on device
```
$ adb sync data
$ adb shell /data/fuzz/${TARGET_ARCH}/keystoreGetWifiHidl_fuzzer/keystoreGetWifiHidl_fuzzer
```
# Fuzzer for libkeystore_attestation_application_id
## Plugin Design Considerations
The fuzzer plugin for libkeystore-attestation-application-id are designed based on the understanding of the library and tries to achieve the following:
##### Maximize code coverage
The configuration parameters are not hardcoded, but instead selected based on
incoming data. This ensures more code paths are reached by the fuzzer.
libkeystore-attestation-application-id supports the following parameters:
1. Package Name (parameter name: `packageName`)
2. Version Code (parameter name: `versionCode`)
3. Uid (parameter name: `uid`)
| Parameter| Valid Values| Configured Value|
|------------- |-------------| ----- |
| `packageName` | `String` | Value obtained from FuzzedDataProvider|
| `versionCode` | `INT64_MIN` to `INT64_MAX` | Value obtained from FuzzedDataProvider|
| `uid` | `0` to `1000` | Value obtained from FuzzedDataProvider|
This also ensures that the plugin is always deterministic for any given input.
##### Maximize utilization of input data
The plugins feed the entire input data to the libkeystore_attestation_application_id module.
This ensures that the plugin tolerates any kind of input (empty, huge,
malformed, etc) and doesnt `exit()` on any input and thereby increasing the
chance of identifying vulnerabilities.
## Build
This describes steps to build keystoreSignature_fuzzer, keystorePackageInfo_fuzzer, keystoreApplicationId_fuzzer and keystoreAttestationId_fuzzer binary.
### Android
#### Steps to build
Build the fuzzer
```
$ mm -j$(nproc) keystoreSignature_fuzzer
$ mm -j$(nproc) keystorePackageInfo_fuzzer
$ mm -j$(nproc) keystoreApplicationId_fuzzer
$ mm -j$(nproc) keystoreAttestationId_fuzzer
```
#### Steps to run
To run on device
```
$ adb sync data
$ adb shell /data/fuzz/${TARGET_ARCH}/keystoreSignature_fuzzer/keystoreSignature_fuzzer
$ adb shell /data/fuzz/${TARGET_ARCH}/keystorePackageInfo_fuzzer/keystorePackageInfo_fuzzer
$ adb shell /data/fuzz/${TARGET_ARCH}/keystoreApplicationId_fuzzer/keystoreApplicationId_fuzzer
$ adb shell /data/fuzz/${TARGET_ARCH}/keystoreAttestationId_fuzzer/keystoreAttestationId_fuzzer
```
## References:
* http://llvm.org/docs/LibFuzzer.html
* https://github.com/google/oss-fuzz