Package com.nimbusds.jose.crypto

Class MACSigner

java.lang.Object

com.nimbusds.jose.crypto.impl.BaseJWSProvider

com.nimbusds.jose.crypto.impl.MACProvider

com.nimbusds.jose.crypto.MACSigner

All Implemented Interfaces:

JCAAware<JCAContext>, JOSEProvider, JWSProvider, JWSSigner

@ThreadSafe
public class MACSigner
extends MACProvider
implements JWSSigner

Message Authentication Code (MAC) signer of JWS objects. Expects a secret key.

See RFC 7518 section 3.2 for more information.

This class is thread-safe.

Supports the following algorithms:

• JWSAlgorithm.HS256
• JWSAlgorithm.HS384
• JWSAlgorithm.HS512

Version:

2016-07-27

Author:

Vladimir Dzhuvinov

Field Summary

Fields inherited from class com.nimbusds.jose.crypto.impl.MACProvider

SUPPORTED_ALGORITHMS

Constructor Summary

Constructors

Constructor	Description
MACSigner(byte[] secret)	Creates a new Message Authentication (MAC) signer.
MACSigner(OctetSequenceKey jwk)	Creates a new Message Authentication (MAC) signer.
MACSigner(String secretString)	Creates a new Message Authentication (MAC) signer.
MACSigner(SecretKey secretKey)	Creates a new Message Authentication (MAC) signer.

Method Summary

Modifier and Type	Method	Description
static Set<JWSAlgorithm>	getCompatibleAlgorithms(int secretLength)	Returns the compatible JWS HMAC algorithms for the specified secret length.
static int	getMinRequiredSecretLength(JWSAlgorithm alg)	Returns the minimal required secret length for the specified HMAC JWS algorithm.
Base64URL	sign(JWSHeader header, byte[] signingInput)	Signs the specified input of a JWS object.

Methods inherited from class com.nimbusds.jose.crypto.impl.MACProvider

getJCAAlgorithmName, getSecret, getSecretKey, getSecretString

Methods inherited from class com.nimbusds.jose.crypto.impl.BaseJWSProvider

getJCAContext, supportedJWSAlgorithms

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.nimbusds.jose.jca.JCAAware

getJCAContext

Methods inherited from interface com.nimbusds.jose.JWSProvider

supportedJWSAlgorithms

Constructor Detail

MACSigner

public MACSigner(byte[] secret)
          throws KeyLengthException

Creates a new Message Authentication (MAC) signer.

Parameters:

secret - The secret. Must be at least 256 bits long and not null.

Throws:

KeyLengthException - If the secret length is shorter than the minimum 256-bit requirement.

MACSigner

public MACSigner(String secretString)
          throws KeyLengthException

Creates a new Message Authentication (MAC) signer.

Parameters:

secretString - The secret as a UTF-8 encoded string. Must be at least 256 bits long and not null.

Throws:

KeyLengthException - If the secret length is shorter than the minimum 256-bit requirement.

MACSigner

public MACSigner(SecretKey secretKey)
          throws KeyLengthException

Creates a new Message Authentication (MAC) signer.

Parameters:

secretKey - The secret key. Must be at least 256 bits long and not null.

Throws:

KeyLengthException - If the secret length is shorter than the minimum 256-bit requirement.

MACSigner

public MACSigner(OctetSequenceKey jwk)
          throws KeyLengthException

Creates a new Message Authentication (MAC) signer.

Parameters:

jwk - The secret as a JWK. Must be at least 256 bits long and not null.

Throws:

KeyLengthException - If the secret length is shorter than the minimum 256-bit requirement.

Method Detail

getMinRequiredSecretLength

public static int getMinRequiredSecretLength(JWSAlgorithm alg)
                                      throws JOSEException

Returns the minimal required secret length for the specified HMAC JWS algorithm.

Parameters:

alg - The HMAC JWS algorithm. Must be supported and not null.

Returns:

The minimal required secret length, in bits.

Throws:

JOSEException - If the algorithm is not supported.

getCompatibleAlgorithms

public static Set<JWSAlgorithm> getCompatibleAlgorithms(int secretLength)

Returns the compatible JWS HMAC algorithms for the specified secret length.

Parameters:

secretLength - The secret length in bits. Must not be negative.

Returns:

The compatible HMAC algorithms, empty set if the secret length is too short for any algorithm.

sign

public Base64URL sign(JWSHeader header,
                      byte[] signingInput)
               throws JOSEException

Description copied from interface: JWSSigner

Signs the specified input of a JWS object.

Specified by:

sign in interface JWSSigner

Parameters:

header - The JSON Web Signature (JWS) header. Must specify a supported JWS algorithm and must not be null.

signingInput - The input to sign. Must not be null.

Returns:

The resulting signature part (third part) of the JWS object.

Throws:

JOSEException - If the JWS algorithm is not supported, if a critical header parameter is not supported or marked for deferral to the application, or if signing failed for some other internal reason.