Tink

Ubuntu	macOS

Introduction

Using crypto in your application shouldn't have to feel like juggling chainsaws in the dark. Tink is a crypto library written by a group of cryptographers and security engineers at Google. It was born out of our extensive experience working with Google's product teams, fixing weaknesses in implementations, and providing simple APIs that can be used safely without needing a crypto background.

Tink provides secure APIs that are easy to use correctly and hard(er) to misuse. It reduces common crypto pitfalls with user-centered design, careful implementation and code reviews, and extensive testing. At Google, Tink is already being used to secure data of many products such as AdMob, Google Pay, Google Assistant, Firebase, the Android Search App, etc.

Getting started

TIP The easiest way to get started with Tink is to install Bazel, then build, run and play with the hello world examples.

Tink performs cryptographic tasks via so-called primitives, each of which is defined via a corresponding interface that specifies the functionality of the primitive. For example, symmetric key encryption is offered via an AEAD-primitive (Authenticated Encryption with Associated Data), that supports two operations:

• encrypt(plaintext, associated_data), which encrypts the given plaintext (using associated_data as additional AEAD-input) and returns the resulting ciphertext
• decrypt(ciphertext, associated_data), which decrypts the given ciphertext (using associated_data as additional AEAD-input) and returns the resulting plaintext

Before implementations of primitives can be used, they must be registered at runtime with Tink, so that Tink "knows" the desired implementations. Here's how you can register all implementations of all primitives in Tink:

    import com.google.crypto.tink.config.TinkConfig;

    TinkConfig.register();

After implementations of primitives have been registered, the basic use of Tink proceeds in three steps:

1. Load or generate the cryptographic key material (a Keyset in Tink terms).
2. Use the key material to get an instance of the chosen primitive.
3. Use that primitive to accomplish the cryptographic task.

Here is how these steps would look like when encrypting or decrypting with an AEAD primitive in Java:

    import com.google.crypto.tink.Aead;
    import com.google.crypto.tink.KeysetHandle;
    import com.google.crypto.tink.aead.AeadFactory;
    import com.google.crypto.tink.aead.AeadKeyTemplates;

    // 1. Generate the key material.
    KeysetHandle keysetHandle = KeysetHandle.generateNew(
        AeadKeyTemplates.AES128_GCM);

    // 2. Get the primitive.
    Aead aead = AeadFactory.getPrimitive(keysetHandle);

    // 3. Use the primitive.
    byte[] ciphertext = aead.encrypt(plaintext, associatedData);

Current Status

• Java and Android, C++ and Obj-C are field tested and ready for production. The latest version is 1.2.0, released on 2018-08-09.

• Tink for Go and JavaScript are in active development.

Learn More

• Java HOW-TO
• C++ HOW-TO
• Obj-C HOW-TO
• Security and Usability Design Goals
• Supported Crypto Primitives
• Key Management
• Tinkey
• Known Issues
• Feature Roadmap
• Java Hacking Guide

Contact and mailing list

If you want to contribute, please read CONTRIBUTING and send us pull requests. You can also report bugs or file feature requests.

If you'd like to talk to the developers or get notified about major product updates, you may want to subscribe to our mailing list. To join, simply send an empty email to tink-users+subscribe@googlegroups.com.

Maintainers

Tink is maintained by (A-Z):

• Haris Andrianakis
• Daniel Bleichenbacher
• Thai Duong
• Charles Lee
• Quan Nguyen
• Bartosz Przydatek

Disclaimer: Tink is not an officially supported Google product.