org.bouncycastle.crypto.engines
Class DESedeWrapEngine

java.lang.Object
  org.bouncycastle.crypto.engines.DESedeWrapEngine

All Implemented Interfaces:

Wrapper

public class DESedeWrapEngine
extends java.lang.Object
implements Wrapper

Wrap keys according to draft-ietf-smime-key-wrap-01.txt.

Note:

• this is based on a draft, and as such is subject to change - don't use this class for anything requiring long term storage.
• if you are using this to wrap triple-des keys you need to set the parity bits on the key and, if it's a two-key triple-des key, pad it yourself.

Field Summary

(package private) byte[]	digest
private CBCBlockCipher	engine Field engine
private boolean	forWrapping Field forWrapping
private byte[]	iv Field iv
private static byte[]	IV2 Field IV2
private KeyParameter	param Field param
private ParametersWithIV	paramPlusIV Field paramPlusIV
(package private) Digest	sha1

Constructor Summary

DESedeWrapEngine()

Method Summary

private byte[]	calculateCMSKeyChecksum(byte[] key) Some key wrap algorithms make use of the Key Checksum defined in CMS [CMS-Algorithms].
private boolean	checkCMSKeyChecksum(byte[] key, byte[] checksum)
java.lang.String	getAlgorithmName() Method getAlgorithmName
void	init(boolean forWrapping, CipherParameters param) Method init
byte[]	unwrap(byte[] in, int inOff, int inLen) Method unwrap
byte[]	wrap(byte[] in, int inOff, int inLen) Method wrap

Methods inherited from class java.lang.Object

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

Field Detail

engine

private CBCBlockCipher engine

Field engine

param

private KeyParameter param

Field param

paramPlusIV

private ParametersWithIV paramPlusIV

Field paramPlusIV

iv

private byte[] iv

Field iv

forWrapping

private boolean forWrapping

Field forWrapping

IV2

private static final byte[] IV2

Field IV2

sha1

Digest sha1

digest

byte[] digest

Constructor Detail

DESedeWrapEngine

public DESedeWrapEngine()

Method Detail

init

public void init(boolean forWrapping,
                 CipherParameters param)

Method init

Specified by:

init in interface Wrapper

Parameters:

forWrapping -

param -

getAlgorithmName

public java.lang.String getAlgorithmName()

Method getAlgorithmName

Specified by:

getAlgorithmName in interface Wrapper

Returns:

the algorithm name "DESede".

wrap

public byte[] wrap(byte[] in,
                   int inOff,
                   int inLen)

Method wrap

Specified by:

wrap in interface Wrapper

Parameters:

in -

inOff -

inLen -

Returns:

the wrapped bytes.

unwrap

public byte[] unwrap(byte[] in,
                     int inOff,
                     int inLen)
              throws InvalidCipherTextException

Method unwrap

Specified by:

unwrap in interface Wrapper

Parameters:

in -

inOff -

inLen -

Returns:

the unwrapped bytes.

Throws:

InvalidCipherTextException

calculateCMSKeyChecksum

private byte[] calculateCMSKeyChecksum(byte[] key)

Some key wrap algorithms make use of the Key Checksum defined in CMS [CMS-Algorithms]. This is used to provide an integrity check value for the key being wrapped. The algorithm is - Compute the 20 octet SHA-1 hash on the key being wrapped. - Use the first 8 octets of this hash as the checksum value.

Parameters:

key -

Returns:

the CMS checksum.

Throws:

java.lang.RuntimeException

See Also:

http://www.w3.org/TR/xmlenc-core/#sec-CMSKeyChecksum

checkCMSKeyChecksum

private boolean checkCMSKeyChecksum(byte[] key,
                                    byte[] checksum)

Parameters:

key -

checksum -

Returns:

true if okay, false otherwise.

See Also:

http://www.w3.org/TR/xmlenc-core/#sec-CMSKeyChecksum