OpenKeychain (for Android)

OpenKeychain is an OpenPGP implementation for Android.
For a more detailed description and installation instructions go to http://www.openkeychain.org .

Travis CI Build Status

How to help the project?

Translate the application

Translations are managed at Transifex, please contribute there at https://www.transifex.com/projects/p/open-keychain/

Contribute Code

1. Join the development mailinglist at http://groups.google.com/d/forum/openpgp-keychain-dev
2. Lookout for interesting issues on our issue page at Github: https://github.com/open-keychain/open-keychain/issues
3. Tell us about your plans on the mailinglist
4. Read this README, especially the notes about coding style
5. Fork OpenKeychain and contribute code (the best part ;) )
6. Open a pull request on Github. I will help with occuring problems and merge your changes back into the main project.

I am happy about every code contribution and appreciate your effort to help us developing OpenKeychain!

Development

Development mailinglist at http://groups.google.com/d/forum/openpgp-keychain-dev

Build with Gradle

1. Get all external submodules with git submodule update --init --recursive
2. Have Android SDK "tools", "platform-tools", and "build-tools" directories in your PATH (http://developer.android.com/sdk/index.html)
3. Open the Android SDK Manager (shell command: android).
   Expand the Tools directory and select "Android SDK Build-tools (Version 19.1)".
   Expand the Extras directory and install "Android Support Repository"
   Select everything for the newest SDK Platform (API-Level 19)
4. Export ANDROID_HOME pointing to your Android SDK
5. Execute ./gradlew build
6. You can install the app with adb install -r OpenKeychain/build/apk/OpenKeychain-debug-unaligned.apk

Build API Demo with Gradle

1. Follow 1-4 from above
2. The example code is available at https://github.com/open-keychain/api-example
3. Execute ./gradlew build

Development with Android Studio

I am using the newest Android Studio for development. Development with Eclipse is currently not possible because I am using the new project structure.

1. Clone the project from github
2. From Android Studio: File -> Import Project -> ...

• Select the cloned top folder if you want to develop on the main project
• Select the "OpenKeychain-API" folder if you want to develop on the API example

3. Import project from external model -> choose Gradle

OpenKeychain's API

OpenKeychain provides two APIs, namely the Intent API and the Remote OpenPGP API. The Intent API can be used without permissions to start OpenKeychain's activities for cryptographic operations, import of keys, etc. However, it always requires user input, so that no malicious application can use this API without user intervention.
The Remote OpenPGP API is more sophisticated and allows to to operations without user interaction in the background. When utilizing this API, OpenKeychain asks the user on first use to grant access for the calling client application.

More technical information and examples about these APIs can be found in the project's wiki:

• Intent API
• Remote OpenPGP API

Libraries

ZXing Barcode Scanner Android Integration

Classes can be found under https://github.com/open-keychain/zxing-android-integration.

1. Copy all classes from https://github.com/zxing/zxing/tree/master/android-integration folder to our git repository.

ZXing QR-Code Classes

Classes can be found under https://github.com/open-keychain/zxing-qr-code. All QR Code related classes were extracted from the ZXing library (https://github.com/zxing/zxing).

Bouncy Castle

Spongy Castle

Spongy Castle is the stock Bouncy Castle libraries with a couple of small changes to make it work on Android. OpenKeychain uses a forked version with some small changes. These changes will been sent to Bouncy Castle, and Spongy Castle will be used again when they have filtered down.

see

• Fork: https://github.com/openpgp-keychain/spongycastle
• Spongy Castle: http://rtyley.github.com/spongycastle/

Bouncy Castle resources

• Repository: https://github.com/bcgit/bc-java
• Issue tracker: http://www.bouncycastle.org/jira/browse/BJA

Documentation

• Documentation project at http://www.cryptoworkshop.com/guide/
• Tests in https://github.com/bcgit/bc-java/tree/master/pg/src/test/java/org/bouncycastle/openpgp/test
• Examples in https://github.com/bcgit/bc-java/tree/master/pg/src/main/java/org/bouncycastle/openpgp/examples
• Mailinglist Archive at http://bouncy-castle.1462172.n4.nabble.com/Bouncy-Castle-Dev-f1462173.html

Notes

Gradle Build System

We try to make our builds as reproducible/deterministic as possible.
When changing build files or dependencies, respect the following requirements:

• No precompiled libraries (you never know what pre-compiled jar files really contain!). All libraries should be forked into the open-keychain Github project and then provided as git submodules in the "extern" folder.
• No dependencies from Maven (also a soft requirement for inclusion in F-Droid)
• Always use a fixed Android Gradle plugin version not a dynamic one, e.g. 0.7.3 instead of 0.7.+ (allows offline builds without lookups for new versions, also some minor Android plugin versions had serious issues, i.e. 0.7.2 and 0.8.1)
• Commit the corresponding Gradle wrapper to the repository (allows easy building for new contributors without the need to install the required Gradle version using a package manager)
• In order to update the build system to a newer gradle version you need to:
  • Update every build.gradle file with the new gradle version and/or gradle plugin version
    • build.gradle
    • OpenKeychain/build.gradle
    • OpenKeychain-API/build.gradle
    • OpenKeychain-API/example-app/build.gradle
    • OpenKeychain-API/libraries/keychain-api-library/build.gradle
  • run ./gradlew wrapper twice to update gradle and download the new gradle jar file
  • commit the new gradle jar and property files

Slow Gradle?

• https://www.timroes.de/2013/09/12/speed-up-gradle/
• Disable Lint checking if it is enabled in build.gradle

Translations

Translations are hosted on Transifex, which is configured by ".tx/config".

1. To pull newest translations install transifex client (e.g. apt-get install transifex-client)
2. Config Transifex client with "~/.transifexrc"
3. Go into root folder of git repo
4. execute tx pull (tx pull -a to get all languages)

see http://help.transifex.net/features/client/index.html#user-client

Coding Style

Code

• Indentation: 4 spaces, no tabs
• Maximum line width for code and comments: 100
• Opening braces don't go on their own line
• Field names: Non-public, non-static fields start with m.
• Acronyms are words: Treat acronyms as words in names, yielding !XmlHttpRequest, getUrl(), etc.
• Fully Qualify Imports: Do not use wildcard-imports such as import foo.*;

The full coding style can be found at http://source.android.com/source/code-style.html

Automated syntax check with CheckStyle

####Linux

1. Paste the tools/checkstyle.xml file to ~/.AndroidStudioPreview/config/codestyles/
2. Go to Settings > Code Style > Java, select OpenPgpChecker, as well as Code Style > XML and select OpenPgpChecker again.
3. Start code inspection and see the results by selecting Analyze > Inspect Code from Android-Studio or you can directly run checkstyle via cli with .tools/checkstyle. Make sure it's executable first.

####Mac OSX

1. Paste the tools/checkstyle.xml file to ~/Library/Preferences/AndroidStudioPreview/codestyles
2. Go to Preferences > Code Style > Java, select OpenPgpChecker, as well as Code Style > XML and select OpenPgpChecker again.
3. Start code inspection and see the results by selecting Analyze > Inspect Code from Android-Studio or you can directly run checkstyle via cli with .tools/checkstyle. Make sure it's executable first.

####Windows

1. Paste the tools/checkstyle.xml file to C:\Users\<UserName>\.AndroidStudioPreview\config\codestyles
2. Go to File > Settings > Code Style > Java, select OpenPgpChecker, as well as Code Style > XML and select OpenPgpChecker again.
3. Start code inspection and see the results by selecting Analyze > Inspect Code from Android-Studio.

Licenses

OpenKechain is licensed under GPLv3+. The full license text can be found in the LICENSE file. Some parts and some libraries are Apache License v2, MIT X11 License (see below).

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.

Libraries

• SpongyCastle
  https://github.com/rtyley/spongycastle
  MIT X11 License

• Android Support Library v4
  http://developer.android.com/tools/support-library/index.html
  Apache License v2

• Android Support Library v7 'appcompat'
  http://developer.android.com/tools/support-library/index.html
  Apache License v2

• HtmlTextView
  https://github.com/dschuermann/html-textview
  Apache License v2

• ZXing
  https://github.com/zxing/zxing
  Apache License v2

• StickyListHeaders
  https://github.com/emilsjolander/StickyListHeaders
  Apache License v2

• Android-Bootstrap
  https://github.com/Bearded-Hen/Android-Bootstrap
  MIT License

• Android AppMsg
  https://github.com/johnkil/Android-AppMsg
  Apache License v2

Images

• icon.svg
  modified version of kgpg_key2_kopete.svgz

• Actionbar icons
  http://developer.android.com/design/downloads/index.html#action-bar-icon-pack

• QR Code Actionbar icon
  https://github.com/openintents/openintents/blob/master/extensions/qrcode_ext/icons/ic_menu_qr_code/ic_menu_qr_code_holo_light/ic_menu_qr_code.svg

• Purple color scheme
  http://android-holo-colors.com/