guide jwt

Table of Contents

• JSON Web Token(JWT)
  • Keystore
  • Dependency
  • Configuration
  • Authentication with JWT via OAuth
  • Login with Username and Password to get JWT
  • Authentication with Kafka

JSON Web Token(JWT)

JWT is an open standard (RFC 7519) for creating Json based access token that assert some number of claims.

For more information about JWT click here

Keystore

A KeyStore is a repository of certificates and keys (public key, private key, or secret key). They can be used for TSL transportation, for encryption and decryption as well as for signing. For demonstration you might create a keystore with openssl, with the following commands:

openssl req -x509 -newkey rsa:4096 -keyout key.pem -out cert.pem -days 365
openssl pkcs12 -export -in cert.pem -inkey key.pem -out example.p12

For Java tooling you may also try the following instead:

keytool -genkeypair -alias devonfw -keypass "password" -storetype PKCS12 -keyalg RSA -keysize 4096 -storepass "password" -keystore keystore.pkcs

Note	Please use reasonable passwords instead of password what should be obvious. Also for the alias the value devonfw is just an example.

Dependency

To use JWT support from devon4j you have to add following required dependency.

<dependency>
  <groupId>com.devonfw.java.starters</groupId>
  <artifactId>devon4j-starter-security-jwt</artifactId>
</dependency>

Configuration

The following properties need to be configured in your application.properties file:

# location of the keystore file, can be any spring resource (such as file or classpath URIs)
security.keystore.location=classpath:config/keystore.pkcs
# type of keystore e.g. "PKCS12" (recommended), "JKS", or "JCEKS"
security.keystore.type=PKCS12
# password the keystore is secured with. Consider using password encryption as described in devon4j configuration guide
security.keystore.password=password
# the algorithm for encryption/decryption and signing - see io.jsonwebtoken.SignatureAlgorithm
security.authentication.jwt.algorithm=RS256
# alias of public/private key in keystore (for validation only public key is used, for creation private key is required)
security.authentication.jwt.alias=devonfw
# the following properties are used if you are validating JWTs (e.g. via JwtAuthenticationFilter)
security.authentication.jwt.validation.expiration-required=false
security.authentication.jwt.validation.max-validity=42h
security.authentication.jwt.validation.not-before-required=false
# the following properties are only used if you are issuing JWTs (e.g. via JwtLoginFilter)
security.authentication.jwt.creation.add-issued-at=true
security.authentication.jwt.creation.validity=4h
security.authentication.jwt.creation.not-before-delay=1m

Authentication with JWT via OAuth

The authentication with JWT via OAuth (HTTP header), will happen via JwtAuthenticationFilter that is automatically added by devon4j-starter-security-jwt via JwtAutoConfiguration. With the starter and auto-configuration we want to make it as easy as possible for you In case you would like to build a server app that e.g. wants to issue JWTs but does not allow authentication via JWT itself, you can use devon4j-security-jwt instead of the starter and do the spring config yourself (pick and choose from JwtAutoConfiguration).

To do this, you need to add the following changes in your BaseWebSecurityConfig:

  @Bean
  public JwtAuthenticationFilter getJwtAuthenticationFilter() {
    return new JwtAuthenticationFilter();
  }

  @Override
  public void configure(HttpSecurity http) throws Exception {
    // ...
    // add this line to the end of this existing method
    http.addFilterBefore(getJwtAuthenticationFilter(), UsernamePasswordAuthenticationFilter.class);
  }

Login with Username and Password to get JWT

To allow a client to login with username and password to get a JWT for sub-sequent requests, you need to do the following changes in your BaseWebSecurityConfig:

  @Bean
  public JwtLoginFilter getJwtLoginFilter() throws Exception {

    JwtLoginFilter jwtLoginFilter = new JwtLoginFilter("/login");
    jwtLoginFilter.setAuthenticationManager(authenticationManager());
    jwtLoginFilter.setUserDetailsService(this.userDetailsService);
    return jwtLoginFilter;
  }

  @Override
  public void configure(HttpSecurity http) throws Exception {
    // ...
    // add this line to the end of this existing method
    http.addFilterBefore(getJwtLoginFilter(), UsernamePasswordAuthenticationFilter.class);
  }

Authentication with Kafka

Authentication with JWT and Kafka is explained in the Kafka guide.