org.eclipse.californium.scandium.dtls.cipher

Class CCMBlockCipher

java.lang.Object

org.eclipse.californium.scandium.dtls.cipher.CCMBlockCipher

public class CCMBlockCipher
extends Object

A generic authenticated encryption block cipher mode which uses the 128-bit block cipher AES. See RFC 3610 for details.

Field Summary

Fields

Modifier and Type	Field and Description
static ThreadLocalCipher	CIPHER
static String	CIPHER_NAME The underlying block cipher.

Constructor Summary

Constructors

Constructor and Description
CCMBlockCipher()

Method Summary

Methods

Modifier and Type	Method and Description
static byte[]	decrypt(SecretKey key, byte[] nonce, byte[] additionalData, byte[] crypted, int numAuthenticationBytes) See RFC 3610 for details.
static byte[]	decrypt(SecretKey key, byte[] nonce, byte[] additionalData, byte[] crypted, int cryptedOffset, int cryptedLength, int numAuthenticationBytes) See RFC 3610 for details.
static byte[]	encrypt(int outputOffset, SecretKey key, byte[] nonce, byte[] additionalData, byte[] message, int numAuthenticationBytes) See RFC 3610 for details.
static byte[]	encrypt(SecretKey key, byte[] nonce, byte[] additionalData, byte[] message, int numAuthenticationBytes) See RFC 3610 for details.

Methods inherited from class java.lang.Object

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

Field Detail

CIPHER_NAME

public static final String CIPHER_NAME

The underlying block cipher.

See Also:

Constant Field Values

CIPHER

public static final ThreadLocalCipher CIPHER

Constructor Detail

CCMBlockCipher

public CCMBlockCipher()

Method Detail

decrypt

public static final byte[] decrypt(SecretKey key,
             byte[] nonce,
             byte[] additionalData,
             byte[] crypted,
             int numAuthenticationBytes)
                            throws GeneralSecurityException

See RFC 3610 for details.

Parameters:

key - the encryption key K.

nonce - the nonce N.

additionalData - the additional authenticated data a.

crypted - the encrypted and authenticated message c.

numAuthenticationBytes - Number of octets in authentication field.

Returns:

the decrypted message

Throws:

GeneralSecurityException - if the message could not be de-crypted, e.g. because the ciphertext's block size is not correct

InvalidMacException - if the message could not be authenticated

decrypt

public static final byte[] decrypt(SecretKey key,
             byte[] nonce,
             byte[] additionalData,
             byte[] crypted,
             int cryptedOffset,
             int cryptedLength,
             int numAuthenticationBytes)
                            throws GeneralSecurityException

See RFC 3610 for details.

Parameters:

key - the encryption key K.

nonce - the nonce N.

additionalData - the additional authenticated data a.

crypted - the encrypted and authenticated message c.

cryptedOffset - offset within crypted

cryptedLength - length within crypted

numAuthenticationBytes - Number of octets in authentication field.

Returns:

the decrypted message

Throws:

GeneralSecurityException - if the message could not be de-crypted, e.g. because the ciphertext's block size is not correct

InvalidMacException - if the message could not be authenticated

encrypt

public static final byte[] encrypt(SecretKey key,
             byte[] nonce,
             byte[] additionalData,
             byte[] message,
             int numAuthenticationBytes)
                            throws GeneralSecurityException

See RFC 3610 for details.

Parameters:

key - the encryption key K.

nonce - the nonce N.

additionalData - the additional authenticated data a.

message - the message to authenticate and encrypt.

numAuthenticationBytes - Number of octets in authentication field.

Returns:

the encrypted and authenticated message.

Throws:

GeneralSecurityException - if the data could not be encrypted, e.g. because the JVM does not support the AES cipher algorithm

encrypt

public static final byte[] encrypt(int outputOffset,
             SecretKey key,
             byte[] nonce,
             byte[] additionalData,
             byte[] message,
             int numAuthenticationBytes)
                            throws GeneralSecurityException

See RFC 3610 for details.

Parameters:

outputOffset - offset of the encrypted message within the resulting byte array. Leaves space for the explicit nonce.

key - the encryption key K.

nonce - the nonce N.

additionalData - the additional authenticated data a.

message - the message to authenticate and encrypt.

numAuthenticationBytes - Number of octets in authentication field.

Returns:

the encrypted and authenticated message.

Throws:

GeneralSecurityException - if the data could not be encrypted, e.g. because the JVM does not support the AES cipher algorithm