org.spongycastle.crypto.signers

Class X931Signer

java.lang.Object

org.spongycastle.crypto.signers.X931Signer

All Implemented Interfaces:

Signer

public class X931Signer
extends java.lang.Object
implements Signer

X9.31-1998 - signing using a hash.

The message digest hash, H, is encapsulated to form a byte string as follows

 EB = 06 || PS || 0xBA || H || TRAILER
 

where PS is a string of bytes all of value 0xBB of length such that |EB|=|n|, and TRAILER is the ISO/IEC 10118 part number† for the digest. The byte string, EB, is converted to an integer value, the message representative, f.

Field Summary

Fields

Modifier and Type	Field and Description
static int	TRAILER_IMPLICIT Deprecated. use ISOTrailers
static int	TRAILER_RIPEMD128 Deprecated. use ISOTrailers
static int	TRAILER_RIPEMD160 Deprecated. use ISOTrailers
static int	TRAILER_SHA1 Deprecated. use ISOTrailers
static int	TRAILER_SHA224 Deprecated. use ISOTrailers
static int	TRAILER_SHA256 Deprecated. use ISOTrailers
static int	TRAILER_SHA384 Deprecated. use ISOTrailers
static int	TRAILER_SHA512 Deprecated. use ISOTrailers
static int	TRAILER_WHIRLPOOL Deprecated. use ISOTrailers

Constructor Summary

Constructors

Constructor and Description
X931Signer(AsymmetricBlockCipher cipher, Digest digest) Constructor for a signer with an explicit digest trailer.
X931Signer(AsymmetricBlockCipher cipher, Digest digest, boolean implicit) Generate a signer with either implicit or explicit trailers for X9.31

Method Summary

Modifier and Type	Method and Description
byte[]	generateSignature() generate a signature for the loaded message using the key we were initialised with.
void	init(boolean forSigning, CipherParameters param) Initialise the signer for signing or verification.
void	reset() reset the internal state
void	update(byte b) update the internal digest with the byte b
void	update(byte[] in, int off, int len) update the internal digest with the byte array in
boolean	verifySignature(byte[] signature) return true if the signature represents a ISO9796-2 signature for the passed in message.

Methods inherited from class java.lang.Object

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

Field Detail

TRAILER_IMPLICIT

public static final int TRAILER_IMPLICIT

Deprecated. use ISOTrailers

See Also:

Constant Field Values

TRAILER_RIPEMD160

public static final int TRAILER_RIPEMD160

Deprecated. use ISOTrailers

See Also:

Constant Field Values

TRAILER_RIPEMD128

public static final int TRAILER_RIPEMD128

Deprecated. use ISOTrailers

See Also:

Constant Field Values

TRAILER_SHA1

public static final int TRAILER_SHA1

Deprecated. use ISOTrailers

See Also:

Constant Field Values

TRAILER_SHA256

public static final int TRAILER_SHA256

Deprecated. use ISOTrailers

See Also:

Constant Field Values

TRAILER_SHA512

public static final int TRAILER_SHA512

Deprecated. use ISOTrailers

See Also:

Constant Field Values

TRAILER_SHA384

public static final int TRAILER_SHA384

Deprecated. use ISOTrailers

See Also:

Constant Field Values

TRAILER_WHIRLPOOL

public static final int TRAILER_WHIRLPOOL

Deprecated. use ISOTrailers

See Also:

Constant Field Values

TRAILER_SHA224

public static final int TRAILER_SHA224

Deprecated. use ISOTrailers

See Also:

Constant Field Values

Constructor Detail

X931Signer

public X931Signer(AsymmetricBlockCipher cipher,
                  Digest digest,
                  boolean implicit)

Generate a signer with either implicit or explicit trailers for X9.31

Parameters:

cipher - base cipher to use for signature creation/verification

digest - digest to use.

implicit - whether or not the trailer is implicit or gives the hash.

X931Signer

public X931Signer(AsymmetricBlockCipher cipher,
                  Digest digest)

Constructor for a signer with an explicit digest trailer.

Parameters:

cipher - cipher to use.

digest - digest to sign with.

Method Detail

init

public void init(boolean forSigning,
                 CipherParameters param)

Description copied from interface: Signer

Initialise the signer for signing or verification.

Specified by:

init in interface Signer

Parameters:

forSigning - true if for signing, false otherwise

param - necessary parameters.

update

public void update(byte b)

update the internal digest with the byte b

Specified by:

update in interface Signer

update

public void update(byte[] in,
                   int off,
                   int len)

update the internal digest with the byte array in

Specified by:

update in interface Signer

reset

public void reset()

reset the internal state

Specified by:

reset in interface Signer

generateSignature

public byte[] generateSignature()
                         throws CryptoException

generate a signature for the loaded message using the key we were initialised with.

Specified by:

generateSignature in interface Signer

Throws:

CryptoException

verifySignature

public boolean verifySignature(byte[] signature)

return true if the signature represents a ISO9796-2 signature for the passed in message.

Specified by:

verifySignature in interface Signer