com.nimbusds.jose.crypto

Class AESEncrypter

java.lang.Object

com.nimbusds.jose.crypto.AESEncrypter

All Implemented Interfaces:

JCAAware<JWEJCAContext>, JOSEProvider, JWEEncrypter, JWEProvider

@ThreadSafe
public class AESEncrypter
extends Object
implements JWEEncrypter

AES and AES GCM key wrap encrypter of JWE objects. Expects an AES key.

Encrypts the plain text with a generated AES key (the Content Encryption Key) according to the specified JOSE encryption method, then wraps the CEK with the specified AES key and returns it alongside the IV, cipher text and authentication tag. See RFC 7518, sections 4.4 and 4.7 for more information.

This class is thread-safe.

Supports the following key management algorithms:

• JWEAlgorithm.A128KW
• JWEAlgorithm.A192KW
• JWEAlgorithm.A256KW
• JWEAlgorithm.A128GCMKW
• JWEAlgorithm.A192GCMKW
• JWEAlgorithm.A256GCMKW

Supports the following content encryption algorithms:

• EncryptionMethod.A128CBC_HS256
• EncryptionMethod.A192CBC_HS384
• EncryptionMethod.A256CBC_HS512
• EncryptionMethod.A128GCM
• EncryptionMethod.A192GCM
• EncryptionMethod.A256GCM
• EncryptionMethod.A128CBC_HS256_DEPRECATED
• EncryptionMethod.A256CBC_HS512_DEPRECATED

Version:

2016-10-13

Author:

Melisa Halsband, Vladimir Dzhuvinov, Dimitar A. Stoikov

Field Summary

Fields

Modifier and Type	Field and Description
static Map<Integer,Set<JWEAlgorithm>>	COMPATIBLE_ALGORITHMS The JWE algorithms compatible with each key size in bits.
static Set<JWEAlgorithm>	SUPPORTED_ALGORITHMS The supported JWE algorithms by the AES crypto provider class.
static Set<EncryptionMethod>	SUPPORTED_ENCRYPTION_METHODS The supported encryption methods by the AES crypto provider class.

Constructor Summary

Constructors

Constructor and Description
AESEncrypter(byte[] keyBytes) Creates a new AES encrypter.
AESEncrypter(OctetSequenceKey octJWK) Creates a new AES encrypter.
AESEncrypter(SecretKey kek) Creates a new AES encrypter.

Method Summary

Modifier and Type	Method and Description
JWECryptoParts	encrypt(JWEHeader header, byte[] clearText) Encrypts the specified clear text of a JWE object.
JWEJCAContext	getJCAContext() Returns the Java Cryptography Architecture (JCA) context.
SecretKey	getKey() Gets the Key Encryption Key (KEK).
Set<EncryptionMethod>	supportedEncryptionMethods() Returns the names of the supported encryption methods by the JWE provier.
Set<JWEAlgorithm>	supportedJWEAlgorithms() Returns the names of the supported algorithms by the JWE provider instance.

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.JWEProvider

supportedEncryptionMethods, supportedJWEAlgorithms

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

getJCAContext

Field Detail

SUPPORTED_ALGORITHMS

public static final Set<JWEAlgorithm> SUPPORTED_ALGORITHMS

The supported JWE algorithms by the AES crypto provider class.

SUPPORTED_ENCRYPTION_METHODS

public static final Set<EncryptionMethod> SUPPORTED_ENCRYPTION_METHODS

The supported encryption methods by the AES crypto provider class.

COMPATIBLE_ALGORITHMS

public static final Map<Integer,Set<JWEAlgorithm>> COMPATIBLE_ALGORITHMS

The JWE algorithms compatible with each key size in bits.

Constructor Detail

AESEncrypter

public AESEncrypter(SecretKey kek)
             throws KeyLengthException

Creates a new AES encrypter.

Parameters:

kek - The Key Encryption Key. Must be 128 bits (16 bytes), 192 bits (24 bytes) or 256 bits (32 bytes). Must not be null.

Throws:

KeyLengthException - If the KEK length is invalid.

AESEncrypter

public AESEncrypter(byte[] keyBytes)
             throws KeyLengthException

Creates a new AES encrypter.

Parameters:

keyBytes - The Key Encryption Key, as a byte array. Must be 128 bits (16 bytes), 192 bits (24 bytes) or 256 bits (32 bytes). Must not be null.

Throws:

KeyLengthException - If the KEK length is invalid.

AESEncrypter

public AESEncrypter(OctetSequenceKey octJWK)
             throws KeyLengthException

Creates a new AES encrypter.

Parameters:

octJWK - The Key Encryption Key, as a JWK. 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:

KeyLengthException - If the KEK length is invalid.

Method Detail

encrypt

public JWECryptoParts encrypt(JWEHeader header,
                              byte[] clearText)
                       throws JOSEException

Description copied from interface: JWEEncrypter

Encrypts the specified clear text of a JWE object.

Specified by:

encrypt in interface JWEEncrypter

Parameters:

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

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

Returns:

The resulting JWE crypto parts.

Throws:

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

getKey

public SecretKey getKey()

Gets the Key Encryption Key (KEK).

Returns:

The Key Encryption Key.

supportedJWEAlgorithms

public Set<JWEAlgorithm> supportedJWEAlgorithms()

Description copied from interface: JWEProvider

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

Specified by:

supportedJWEAlgorithms in interface JWEProvider

Returns:

The supported JWE algorithms, empty set if none.

supportedEncryptionMethods

public Set<EncryptionMethod> supportedEncryptionMethods()

Description copied from interface: JWEProvider

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

Specified by:

supportedEncryptionMethods in interface JWEProvider

Returns:

The supported encryption methods, empty set if none.

getJCAContext

public JWEJCAContext getJCAContext()

Description copied from interface: JCAAware

Returns the Java Cryptography Architecture (JCA) context. May be used to set a specific JCA security provider or secure random generator.

Specified by:

getJCAContext in interface JCAAware<JWEJCAContext>

Returns:

The JCA context. Not null.