A Java implementation of JSON Web Tokens (draft-ietf-oauth-json-web-token-08).
If you're looking for an Android version of the JWT Decoder take a look at our JWTDecode.Android library.
<dependency>
<groupId>com.auth0</groupId>
<artifactId>java-jwt</artifactId>
<version>3.1.0</version>
</dependency>
compile 'com.auth0:java-jwt:3.1.0'
The library implements JWT Verification and Signing using the following algorithms:
JWS | Algorithm | Description |
---|---|---|
HS256 | HMAC256 | HMAC with SHA-256 |
HS384 | HMAC384 | HMAC with SHA-384 |
HS512 | HMAC512 | HMAC with SHA-512 |
RS256 | RSA256 | RSASSA-PKCS1-v1_5 with SHA-256 |
RS384 | RSA384 | RSASSA-PKCS1-v1_5 with SHA-384 |
RS512 | RSA512 | RSASSA-PKCS1-v1_5 with SHA-512 |
ES256 | ECDSA256 | ECDSA with curve P-256 and SHA-256 |
ES384 | ECDSA384 | ECDSA with curve P-384 and SHA-384 |
ES512 | ECDSA512 | ECDSA with curve P-521 and SHA-512 |
You'll first need to create a JWTCreator
instance by calling JWT.create()
. Use the builder to define the custom Claims your token needs to have. Finally to get the String token call sign()
and pass the Algorithm instance.
- Example using
HS256
try {
String token = JWT.create()
.withIssuer("auth0")
.sign(Algorithm.HMAC256("secret"));
} catch (JWTCreationException exception){
//Invalid Signing configuration / Couldn't convert Claims.
}
- Example using
RS256
PrivateKey key = //Get the key instance
try {
String token = JWT.create()
.withIssuer("auth0")
.sign(Algorithm.RSA256(key));
} catch (JWTCreationException exception){
//Invalid Signing configuration / Couldn't convert Claims.
}
If a Claim couldn't be converted to JSON or the Key used in the signing process was invalid a JWTCreationException
will raise.
You'll first need to create a JWTVerifier
instance by calling JWT.require()
and passing the Algorithm instance. If you require the token to have specific Claim values, use the builder to define them. The instance returned by the method build()
is reusable, so you can define it once and use it to verify different tokens. Finally call verifier.verify()
passing the token.
- Example using
HS256
String token = "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXUyJ9.eyJpc3MiOiJhdXRoMCJ9.AbIJTDMFc7yUa5MhvcP03nJPyCPzZtQcGEp-zWfOkEE";
try {
JWTVerifier verifier = JWT.require(Algorithm.HMAC256("secret"))
.withIssuer("auth0")
.build(); //Reusable verifier instance
JWT jwt = verifier.verify(token);
} catch (JWTVerificationException exception){
//Invalid signature/claims
}
- Example using
RS256
String token = "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXUyJ9.eyJpc3MiOiJhdXRoMCJ9.AbIJTDMFc7yUa5MhvcP03nJPyCPzZtQcGEp-zWfOkEE";
PublicKey key = //Get the key instance
try {
JWTVerifier verifier = JWT.require(Algorithm.RSA256(key))
.withIssuer("auth0")
.build(); //Reusable verifier instance
JWT jwt = verifier.verify(token);
} catch (JWTVerificationException exception){
//Invalid signature/claims
}
If the token has an invalid signature or the Claim requirement is not met, a JWTVerificationException
will raise.
The JWT token may include DateNumber fields that can be used to validate that:
- The token was issued in a past date
"iat" < TODAY
- The token hasn't expired yet
"exp" > TODAY
and - The token can already be used.
"nbf" > TODAY
When verifying a token the time validation occurs automatically, resulting in a JWTVerificationException
being throw when the values are invalid. If any of the previous fields are missing they won't be considered in this validation.
To specify a leeway window in which the Token should still be considered valid, use the acceptLeeway()
method in the JWTVerifier
builder and pass a positive seconds value. This applies to every item listed above.
JWTVerifier verifier = JWT.require(Algorithm.RSA256(key))
.acceptLeeway(1) // 1 sec for nbf, iat and exp
.build();
You can also specify a custom value for a given Date claim and override the default one for only that claim.
JWTVerifier verifier = JWT.require(Algorithm.RSA256(key))
.acceptLeeway(1) //1 sec for nbf and iat
.acceptExpiresAt(5) //5 secs for exp
.build();
If you need to test this behaviour in your lib/app cast the Verification
instance to a BaseVerification
to gain visibility of the verification.build()
method that accepts a custom Clock
. e.g.:
BaseVerification verification = (BaseVerification) JWT.require(Algorithm.RSA256(key))
.acceptLeeway(1)
.acceptExpiresAt(5);
Clock clock = new CustomClock(); //Must implement Clock interface
JWTVerifier verifier = verification.build(clock);
String token = "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXUyJ9.eyJpc3MiOiJhdXRoMCJ9.AbIJTDMFc7yUa5MhvcP03nJPyCPzZtQcGEp-zWfOkEE";
try {
JWT jwt = JWT.decode(token);
} catch (JWTDecodeException exception){
//Invalid token
}
If the token has an invalid syntax or the header or payload are not JSONs, a JWTDecodeException
will raise.
Returns the Algorithm value or null if it's not defined in the Header.
String algorithm = jwt.getAlgorithm();
Returns the Type value or null if it's not defined in the Header.
String type = jwt.getType();
Returns the Content Type value or null if it's not defined in the Header.
String contentType = jwt.getContentType();
Returns the Key Id value or null if it's not defined in the Header.
String keyId = jwt.getKeyId();
Additional Claims defined in the token's Header can be obtained by calling getHeaderClaim()
and passing the Claim name. A Claim will always be returned, even if it can't be found. You can check if a Claim's value is null by calling claim.isNull()
.
Claim claim = jwt.getHeaderClaim("owner");
When creating a Token with the JWT.create()
you can specify header Claims by calling withHeader()
and passing both the map of claims.
Map<String, Object> headerClaims = new HashMap();
headerclaims.put("owner", "auth0");
JWT.create()
.withHeader(headerClaims)
.sign(Algorithm.HMAC256("secret"));
The
alg
andtyp
values will always be included in the Header after the signing process.
Returns the Issuer value or null if it's not defined in the Payload.
String issuer = jwt.getIssuer();
Returns the Subject value or null if it's not defined in the Payload.
String subject = jwt.getSubject();
Returns the Audience value or null if it's not defined in the Payload.
List<String> audience = jwt.getAudience();
Returns the Expiration Time value or null if it's not defined in the Payload.
Date expiresAt = jwt.getExpiresAt();
Returns the Not Before value or null if it's not defined in the Payload.
Date notBefore = jwt.getNotBefore();
Returns the Issued At value or null if it's not defined in the Payload.
Date issuedAt = jwt.getIssuedAt();
Returns the JWT ID value or null if it's not defined in the Payload.
String id = jwt.getId();
Additional Claims defined in the token's Payload can be obtained by calling getClaims()
or getClaim()
and passing the Claim name. A Claim will always be returned, even if it can't be found. You can check if a Claim's value is null by calling claim.isNull()
.
Map<String, Claim> claims = jwt.getClaims(); //Key is the Claim name
Claim claim = claims.get("isAdmin");
or
Claim claim = jwt.getClaim("isAdmin");
When creating a Token with the JWT.create()
you can specify a custom Claim by calling withClaim()
and passing both the name and the value.
JWT.create()
.withClaim("name", 123)
.withArrayClaim("array", new Integer[]{1, 2, 3})
.sign(Algorithm.HMAC256("secret"));
You can also verify custom Claims on the JWT.require()
by calling withClaim()
and passing both the name and the required value.
JWT.require(Algorithm.HMAC256("secret"))
.withClaim("name", 123)
.withArrayClaim("array", 1, 2, 3)
.build()
.verify("my.jwt.token");
Currently supported classes for custom JWT Claim creation and verification are: Boolean, Integer, Double, String, Date and Arrays of type String and Integer.
The Claim class is a wrapper for the Claim values. It allows you to get the Claim as different class types. The available helpers are:
- asBoolean(): Returns the Boolean value or null if it can't be converted.
- asInt(): Returns the Integer value or null if it can't be converted.
- asDouble(): Returns the Double value or null if it can't be converted.
- asString(): Returns the String value or null if it can't be converted.
- asDate(): Returns the Date value or null if it can't be converted. This must be a NumericDate (Unix Epoch/Timestamp). Note that the JWT Standard specified that all the NumericDate values must be in seconds.
To obtain a Claim as a Collection you'll need to provide the Class Type of the contents to convert from.
- as(class): Returns the value parsed as Class Type. For collections you should use the
asArray
andasList
methods. - asArray(class): Returns the value parsed as an Array of elements of type Class Type, or null if the value isn't a JSON Array.
- asList(class): Returns the value parsed as a List of elements of type Class Type, or null if the value isn't a JSON Array.
If the values can't be converted to the given Class Type a JWTDecodeException
will raise.
Auth0 helps you to:
- Add authentication with multiple authentication sources, either social like Google, Facebook, Microsoft Account, LinkedIn, GitHub, Twitter, Box, Salesforce, among others, or enterprise identity systems like Windows Azure AD, Google Apps, Active Directory, ADFS or any SAML Identity Provider.
- Add authentication through more traditional username/password databases.
- Add support for linking different user accounts with the same user.
- Support for generating signed Json Web Tokens to call your APIs and flow the user identity securely.
- Analytics of how, when and where users are logging in.
- Pull data from other sources and add it to the user profile, through JavaScript rules.
- Go to Auth0 and click Sign Up.
- Use Google, GitHub or Microsoft Account to login.
If you have found a bug or if you have a feature request, please report them at this repository issues section. Please do not report security vulnerabilities on the public GitHub issue tracker. The Responsible Disclosure Program details the procedure for disclosing security issues.
This project is licensed under the MIT license. See the LICENSE file for more info.