README.md

Tink

A multi-language, cross-platform library that provides cryptographic APIs that are secure, easy to use correctly, and hard(er) to misuse.

Ubuntu	macOS

Index

1. Introduction
2. Getting started
3. Current status
4. Learn more
5. Contact and mailing list
6. Maintainers

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.

To get a quick overview of Tink design please take a look at slides from a talk about Tink presented at Real World Crypto 2019.

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.AeadKeyTemplates;

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

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

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

Current status