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README.md

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+# SafeContentResolver
+
+A replacement for Android's [`ContentResolver`](https://developer.android.com/reference/android/content/ContentResolver.html)
+that protects against the *Surreptitious Sharing* attack.
+
+## Surreptitious Sharing
+
+Read all about it: <link>
+
+## Usage
+
+Replace all occurrences of [`ContentResolver.openInputStream()`](https://developer.android.com/reference/android/content/ContentResolver.html#openInputStream(android.net.Uri))
+where URIs provided by other apps are opened with `SafeContentResolver.openInputStream()`.
+
+The library comes in two flavors `safe-content-resolver-v14` and `safe-content-resolver-v21`. The former includes
+native code to be able to invoke the `fstat` system call that is used to retrieve the owner of a file. Starting with
+Lollipop (API 21) the framework includes the class [`Os`](https://developer.android.com/reference/android/system/Os.html)
+to access this functionality. So `safe-content-resolver-v21` is free of native code and thus much smaller.
+
+To retrieve an instance of `SafeContentResolver` use:
+```java
+SafeContentResolver safeContentResolver = SafeContentResolverCompat.newInstance(context);
+```
+
+If your `minSdkVersion` is 21 or higher you only need to include `safe-content-resolver-v21` and use the following code:
+```java
+SafeContentResolver safeContentResolver = SafeContentResolver.newInstance(context);
+```
+
+## Include the library
+
+```groovy
+compile 'de.cketti.safecontentresolver:safe-content-resolver-v14:0.0.1'
+```
+
+Or, if you're using `minSdkVersion` 21 or higher:
+
+```groovy
+compile 'de.cketti.safecontentresolver:safe-content-resolver-v21:0.0.1'
+```
+
+## Native code
+
+`safe-content-resolver-v14` contains native code for the following ABIs:
+* armeabi
+* armeabi-v7a
+* arm64-v8a
+* x86
+* x86_64
+* mips
+* mips64
+
+If you don't want to include all of them in your APK you might want to look into
+[ABIs Splits](http://tools.android.com/tech-docs/new-build-system/user-guide/apk-splits#TOC-ABIs-Splits).
+
+
+## License
+
+ 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.