JWKS-Client is a library written in Rust to decode and validate JWT tokens using a JSON Web Key Store.

Breaking Change

Now at version 2.0. Support for async/await thanks to Genna Wingert. Requires Rust Stable 1.39 or higher

** IMPORTANT **

JWKS-Client was designed to work with a project that uses Rocket. Unfortunately, the version of Rocket in crates.io is not compatible with the version of Ring required for JWKS-Client. Until the next version of Rocket is published, consider using the following in your Cargo.toml:

[dependencies]
jwks-client = "0.1.4"
rocket = { git = "https://github.com/jfbilodeau/Rocket", version = "0.5.0-dev"}
# Other dependencies...

[dependencies.rocket_contrib]
version = "0.5.0-dev"
git = "https://github.com/jfbilodeau/Rocket"
# Other options...

Features

Library wide:

• No panic!
• Build with Rust stable (1.40)
• Designed for a production system (not an academic project)
• Concise results (see error::Type for example)

JWKS key store

• Download key set from HTTP address
• Decode JWT tokens into header, payload and signature
• Verify token signature, expiry and not-before
• Determine when keys should be refreshed

JWT:

• Transfer header and payload in user-defined struct. See the example below[^1]
• Accessor for standard header and payload fields

JWKS-Client was create specifically to decode GCP/Firebase JWT but should be useable with little to no modification. Contact me to propose support for different JWKS key store. Feedback, suggestions, complaints and criticism is appreciated.

Basic Usage

The following demonstrates how to load a set of keys from an HTTP address and verify a JWT token using those keys:

use jwks_client::error::Error;
use jwks_client::keyset::KeyStore;

#[tokio::main]
async fn main() {
    let jkws_url = "https://raw.githubusercontent.com/jfbilodeau/jwks-client/0.1.8/test/test-jwks.json";

    let key_set = KeyStore::new_from(jkws_url.to_owned()).await.unwrap();

    // ...

    let token = "eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCIsImtpZCI6IjEifQ.eyJuYW1lIjoiQWRhIExvdmVsYWNlIiwiaXNzIjoiaHR0cHM6Ly9jaHJvbm9nZWFycy5jb20vdGVzdCIsImF1ZCI6InRlc3QiLCJhdXRoX3RpbWUiOjEwMCwidXNlcl9pZCI6InVpZDEyMyIsInN1YiI6InNidTEyMyIsImlhdCI6MjAwLCJleHAiOjUwMCwibmJmIjozMDAsImVtYWlsIjoiYWxvdmVsYWNlQGNocm9ub2dlYXJzLmNvbSJ9.eTQnwXrri_uY55fS4IygseBzzbosDM1hP153EZXzNlLH5s29kdlGt2mL_KIjYmQa8hmptt9RwKJHBtw6l4KFHvIcuif86Ix-iI2fCpqNnKyGZfgERV51NXk1THkgWj0GQB6X5cvOoFIdHa9XvgPl_rVmzXSUYDgkhd2t01FOjQeeT6OL2d9KdlQHJqAsvvKVc3wnaYYoSqv2z0IluvK93Tk1dUBU2yWXH34nX3GAVGvIoFoNRiiFfZwFlnz78G0b2fQV7B5g5F8XlNRdD1xmVZXU8X2-xh9LqRpnEakdhecciFHg0u6AyC4c00rlo_HBb69wlXajQ3R4y26Kpxn7HA";

    match key_set.verify(token) {
        Ok(jwt) => {
            println!("name={}", jwt.payload().get_str("name").unwrap());
        }
        Err(Error { msg, typ: _ }) => {
            eprintln!("Could not verify token. Reason: {}", msg);
        }
    }
}

JWKS-Client can be use to simply decode a JWT token without validating the signature.

use jwks_client::keyset::KeyStore;

fn main() {
    let key_store = KeyStore::new();

    let token = "eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCIsImtpZCI6IjEifQ.eyJuYW1lIjoiQWRhIExvdmVsYWNlIiwiaXNzIjoiaHR0cHM6Ly9jaHJvbm9nZWFycy5jb20vdGVzdCIsImF1ZCI6InRlc3QiLCJhdXRoX3RpbWUiOjEwMCwidXNlcl9pZCI6InVpZDEyMyIsInN1YiI6InNidTEyMyIsImlhdCI6MjAwLCJleHAiOjUwMCwibmJmIjozMDAsImVtYWlsIjoiYWxvdmVsYWNlQGNocm9ub2dlYXJzLmNvbSJ9.eTQnwXrri_uY55fS4IygseBzzbosDM1hP153EZXzNlLH5s29kdlGt2mL_KIjYmQa8hmptt9RwKJHBtw6l4KFHvIcuif86Ix-iI2fCpqNnKyGZfgERV51NXk1THkgWj0GQB6X5cvOoFIdHa9XvgPl_rVmzXSUYDgkhd2t01FOjQeeT6OL2d9KdlQHJqAsvvKVc3wnaYYoSqv2z0IluvK93Tk1dUBU2yWXH34nX3GAVGvIoFoNRiiFfZwFlnz78G0b2fQV7B5g5F8XlNRdD1xmVZXU8X2-xh9LqRpnEakdhecciFHg0u6AyC4c00rlo_HBb69wlXajQ3R4y26Kpxn7HA";

    let jwt = key_store.decode(token).unwrap();

    if jwt.expired().unwrap_or(false) {
        println!("Sorry, token expired")
    } else {
        let result = jwt.payload().get_str("name");

        match result {
            Some(name) => {
                println!("Welcome, {}!", name);
            }
            None => {
                println!("Welcome, anonymous");
            }
        }
    }
}

JWKS-Client offers descriptive error results:

use jwks_client::error::{Error, Type};
use jwks_client::keyset::KeyStore;

#[rustfmt::skip]
#[tokio::main]
async fn main() {
    let url = "https://raw.githubusercontent.com/jfbilodeau/jwks-client/0.1.8/test/test-jwks.json";
    let token = "eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCIsImtpZCI6IjEifQ.eyJuYW1lIjoiQWRhIExvdmVsYWNlIiwiaXNzIjoiaHR0cHM6Ly9jaHJvbm9nZWFycy5jb20vdGVzdCIsImF1ZCI6InRlc3QiLCJhdXRoX3RpbWUiOjEwMCwidXNlcl9pZCI6InVpZDEyMyIsInN1YiI6InNidTEyMyIsImlhdCI6MjAwLCJleHAiOjUwMCwibmJmIjozMDAsImVtYWlsIjoiYWxvdmVsYWNlQGNocm9ub2dlYXJzLmNvbSJ9.eTQnwXrri_uY55fS4IygseBzzbosDM1hP153EZXzNlLH5s29kdlGt2mL_KIjYmQa8hmptt9RwKJHBtw6l4KFHvIcuif86Ix-iI2fCpqNnKyGZfgERV51NXk1THkgWj0GQB6X5cvOoFIdHa9XvgPl_rVmzXSUYDgkhd2t01FOjQeeT6OL2d9KdlQHJqAsvvKVc3wnaYYoSqv2z0IluvK93Tk1dUBU2yWXH34nX3GAVGvIoFoNRiiFfZwFlnz78G0b2fQV7B5g5F8XlNRdD1xmVZXU8X2-xh9LqRpnEakdhecciFHg0u6AyC4c00rlo_HBb69wlXajQ3R4y26Kpxn7HA";

    let key_set = KeyStore::new_from(url.to_owned()).await.unwrap();

    match key_set.verify(token) {
        Ok(jwt) => {
            println!("name={}", jwt.payload().get_str("name").unwrap());
        }
        Err(Error {
            msg,
            typ: Type::Header,
        }) => {
            eprintln!("Problem with header. Message: {}", msg);
        }
        Err(Error {
            msg,
            typ: Type::Payload,
        }) => {
            eprintln!("Problem with payload. Message: {}", msg);
        }
        Err(Error {
            msg,
            typ: Type::Signature,
        }) => {
            eprintln!("Problem with signature. Message: {}", msg);
        }
        Err(Error {
            msg: _,
            typ: Type::Expired,
        }) => {
            eprintln!("Token is expired.");
        }
        Err(Error {
            msg: _,
            typ: Type::Early,
        }) => {
            eprintln!("Too early to use token.");
        }
        Err(e) => {
            eprintln!("Something else went wrong. Message {:?}", e);
        }
    }
}

[^1] JWKS-Client can decode a JWT payload (claims) into a struct:

use serde_derive::Deserialize;

use jwks_client::keyset::KeyStore;

fn main() {
    #[derive(Deserialize)]
    pub struct MyClaims {
        pub iss: String,
        pub name: String,
        pub email: String,
    }

    let url = "https://raw.githubusercontent.com/jfbilodeau/jwks-client/0.1.8/test/test-jwks.json";

    let key_store = KeyStore::new_from(url.to_owned()).unwrap();

    let token = "eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCIsImtpZCI6IjEifQ.eyJuYW1lIjoiQWRhIExvdmVsYWNlIiwiaXNzIjoiaHR0cHM6Ly9jaHJvbm9nZWFycy5jb20vdGVzdCIsImF1ZCI6InRlc3QiLCJhdXRoX3RpbWUiOjEwMCwidXNlcl9pZCI6InVpZDEyMyIsInN1YiI6InNidTEyMyIsImlhdCI6MjAwLCJleHAiOjUwMCwibmJmIjozMDAsImVtYWlsIjoiYWxvdmVsYWNlQGNocm9ub2dlYXJzLmNvbSJ9.eTQnwXrri_uY55fS4IygseBzzbosDM1hP153EZXzNlLH5s29kdlGt2mL_KIjYmQa8hmptt9RwKJHBtw6l4KFHvIcuif86Ix-iI2fCpqNnKyGZfgERV51NXk1THkgWj0GQB6X5cvOoFIdHa9XvgPl_rVmzXSUYDgkhd2t01FOjQeeT6OL2d9KdlQHJqAsvvKVc3wnaYYoSqv2z0IluvK93Tk1dUBU2yWXH34nX3GAVGvIoFoNRiiFfZwFlnz78G0b2fQV7B5g5F8XlNRdD1xmVZXU8X2-xh9LqRpnEakdhecciFHg0u6AyC4c00rlo_HBb69wlXajQ3R4y26Kpxn7HA";

    let jwt = key_store.decode(token).unwrap();

    let claims = jwt.payload().into::<MyClaims>().unwrap();

    println!("Issuer: {}", claims.iss);
    println!("Name: {}", claims.name);
    println!("Email: {}", claims.email);
}

History

• 0.2.0

  • Breaking Change: Support for async/await (Thanks to Genna Wingert)

• 0.1.8

  • Fixed issued #1 (Thanks to Tim Schuster for reporting and assisting)

• 0.1.7

  • Updated dependencies

• 0.1.6

  • Added key_set::KeyStore::should_refresh() to test if keys should be refreshed
  • Added key_set::KeyStore::refresh_interval to determine how early keys should be refreshed before they expire
  • Some more documentation

• 0.1.5:

  • Added readme = "README.md" to Cargo.toml

• 0.1.4:

  • Updated documentation--specifically how to use JWKS-Client with Rocket
  • Added the ability to determine if keys should be refreshed from the KeyStore
  • Fixed example on this page--they are now directly from ./examples/*

• 0.1.3:

  • Change the license to be MIT/Apache
  • Moved demos into ./example
  • Added the ability to verify if keys need to be refreshed in the keystore based on the cache-control header

• 0.1.2: (Sorry for the breaking changes)

  • Rename module jwks to keyset
  • Renamed struct Jwks to KeyStore
  • Expanded documentation a bit
  • Fixed some demos

• 0.1.1: Original version

TODO:

• Lots More documentation :P
• Automatically refresh keys

(Made with ❤️ with Rust)