com.nimbusds.jose.crypto

Class DirectEncrypter

java.lang.Object

com.nimbusds.jose.crypto.DirectEncrypter

All Implemented Interfaces:

AlgorithmProvider, JWEAlgorithmProvider, JWEEncrypter

@ThreadSafe
public class DirectEncrypter
extends Object
implements JWEEncrypter

Direct encrypter of JWE objects with a shared symmetric key. This class is thread-safe.

Supports the following JWE algorithms:

• JWEAlgorithm.DIR

Supports the following encryption methods:

• EncryptionMethod.A128CBC_HS256
• EncryptionMethod.A192CBC_HS384
• EncryptionMethod.A256CBC_HS512
• EncryptionMethod.A128GCM
• EncryptionMethod.A192GCM
• EncryptionMethod.A256GCM

Version:

$version$ (2014-08-20)

Author:

Vladimir Dzhuvinov

Field Summary

Fields

Modifier and Type	Field and Description
protected Provider	contentEncryptionProvider The JCA provider for the content encryption, null if not specified (implies default one).
protected Provider	keyEncryptionProvider The JCA provider for the key encryption, null if not specified (implies default one).
protected Provider	macProvider The JCA provider for the MAC computation, null if not specified (implies default one).
static Set<JWEAlgorithm>	SUPPORTED_ALGORITHMS The supported JWE algorithms.
static Set<EncryptionMethod>	SUPPORTED_ENCRYPTION_METHODS The supported encryption methods.

Constructor Summary

Constructors

Constructor and Description
DirectEncrypter(byte[] keyBytes) Creates a new direct encrypter.
DirectEncrypter(SecretKey key) Creates a new direct encrypter.

Method Summary

Methods

Modifier and Type	Method and Description
JWECryptoParts	encrypt(JWEHeader readOnlyJWEHeader, byte[] bytes) Encrypts the specified clear text of a JWE object.
SecretKey	getKey() Gets the shared symmetric key.
protected SecureRandom	getSecureRandom() Returns the secure random generator for this JWE provider.
void	setContentEncryptionProvider(Provider provider) Sets a specific JCA provider for the content encryption.
void	setKeyEncryptionProvider(Provider provider) Sets a specific JCA provider for the key encryption.
void	setMACProvider(Provider provider) Sets a specific JCA provider for MAC computation (where required by the JWE encryption method).
void	setProvider(Provider provider) Sets a specific JCA provider, to be used for all operations.
void	setSecureRandom(SecureRandom randomGen) Sets a specific secure random generator for the initialisation vector and other purposes requiring a random number.
Set<JWEAlgorithm>	supportedAlgorithms() Returns the names of the supported JWE algorithms.
Set<EncryptionMethod>	supportedEncryptionMethods() Returns the names of the supported encryption methods.

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.JWEAlgorithmProvider

setContentEncryptionProvider, setKeyEncryptionProvider, setMACProvider, setSecureRandom, supportedAlgorithms, supportedEncryptionMethods

Methods inherited from interface com.nimbusds.jose.AlgorithmProvider

setProvider

Field Detail

SUPPORTED_ALGORITHMS

public static final Set<JWEAlgorithm> SUPPORTED_ALGORITHMS

The supported JWE algorithms.

SUPPORTED_ENCRYPTION_METHODS

public static final Set<EncryptionMethod> SUPPORTED_ENCRYPTION_METHODS

The supported encryption methods.

keyEncryptionProvider

protected Provider keyEncryptionProvider

The JCA provider for the key encryption, null if not specified (implies default one).

contentEncryptionProvider

protected Provider contentEncryptionProvider

The JCA provider for the content encryption, null if not specified (implies default one).

macProvider

protected Provider macProvider

The JCA provider for the MAC computation, null if not specified (implies default one).

Constructor Detail

DirectEncrypter

public DirectEncrypter(SecretKey key)
                throws JOSEException

Creates a new direct encrypter.

Parameters:

key - The shared symmetric key. Its algorithm must be "AES". Must be 128 bits (16 bytes), 192 bits (24 bytes), 256 bits (32 bytes), 384 bits (48 bytes) or 512 bits (64 bytes) long. Must not be null.

Throws:

JOSEException - If the key length or algorithm are unexpected, or if the underlying secure random generator couldn't be instantiated.

DirectEncrypter

public DirectEncrypter(byte[] keyBytes)
                throws JOSEException

Creates a new direct encrypter.

Parameters:

keyBytes - The shared symmetric key, as a byte array. Must be 128 bits (16 bytes), 192 bits (24 bytes), 256 bits (32 bytes), 384 bits (48 bytes) or 512 bits (64 bytes) long. Must not be null.

Throws:

JOSEException - If the key length or algorithm are unexpected, or if the underlying secure random generator couldn't be instantiated.

Method Detail

encrypt

public JWECryptoParts encrypt(JWEHeader readOnlyJWEHeader,
                     byte[] bytes)
                       throws JOSEException

Description copied from interface: JWEEncrypter

Encrypts the specified clear text of a JWE object.

Specified by:

encrypt in interface JWEEncrypter

Parameters:

readOnlyJWEHeader - The JSON Web Encryption (JWE) header. Must specify a supported JWE algorithm and must not be null.

bytes - The clear text to encrypt. Must not be null.

Returns:

The resulting JWE crypto parts.

Throws:

JOSEException - If the JWE algorithm is not supported or if encryption failed for some other reason.

getKey

public SecretKey getKey()

Gets the shared symmetric key.

Returns:

The key.

supportedAlgorithms

public Set<JWEAlgorithm> supportedAlgorithms()

Description copied from interface: JWEAlgorithmProvider

Returns the names of the supported JWE algorithms. These correspond to the alg JWE header parameter.

Specified by:

supportedAlgorithms in interface JWEAlgorithmProvider

Returns:

The supported JWE algorithms, empty set if none.

supportedEncryptionMethods

public Set<EncryptionMethod> supportedEncryptionMethods()

Description copied from interface: JWEAlgorithmProvider

Returns the names of the supported encryption methods. These correspond to the enc JWE header parameter.

Specified by:

supportedEncryptionMethods in interface JWEAlgorithmProvider

Returns:

The supported encryption methods, empty set if none.

setProvider

public void setProvider(Provider provider)

Description copied from interface: AlgorithmProvider

Sets a specific JCA provider, to be used for all operations.

Specified by:

setProvider in interface AlgorithmProvider

Parameters:

provider - The JCA provider, or null to use the default one.

setKeyEncryptionProvider

public void setKeyEncryptionProvider(Provider provider)

Description copied from interface: JWEAlgorithmProvider

Sets a specific JCA provider for the key encryption.

Specified by:

setKeyEncryptionProvider in interface JWEAlgorithmProvider

Parameters:

provider - The JCA provider, or null to use the default one.

setContentEncryptionProvider

public void setContentEncryptionProvider(Provider provider)

Description copied from interface: JWEAlgorithmProvider

Sets a specific JCA provider for the content encryption.

Specified by:

setContentEncryptionProvider in interface JWEAlgorithmProvider

Parameters:

provider - The JCA provider, or null to use the default one.

setMACProvider

public void setMACProvider(Provider provider)

Description copied from interface: JWEAlgorithmProvider

Sets a specific JCA provider for MAC computation (where required by the JWE encryption method).

Specified by:

setMACProvider in interface JWEAlgorithmProvider

Parameters:

provider - The JCA provider, or null to use the default one.

setSecureRandom

public void setSecureRandom(SecureRandom randomGen)

Description copied from interface: JWEAlgorithmProvider

Sets a specific secure random generator for the initialisation vector and other purposes requiring a random number.

Specified by:

setSecureRandom in interface JWEAlgorithmProvider

Parameters:

randomGen - The secure random generator, or null to use the default one.

getSecureRandom

protected SecureRandom getSecureRandom()

Returns the secure random generator for this JWE provider.

Returns:

The secure random generator.