gnu.crypto.sig
Interface ISignature
- Cloneable
- BaseSignature, DSSSignature, RSAPKCS1V1_5Signature, RSAPSSSignature
public interface ISignature
extends Cloneable
The visible methods of every signature-with-appendix scheme.
The Handbook of Applied Cryptography (HAC), by A. Menezes & al. states:
"Digital signature schemes which require the message as input to the
verification algorithm are called
digital signature schemes with
appendix. ... They rely on cryptographic hash functions rather than
customised redundancy functions, and are less prone to existential forgery
attacks."
References:
- Handbook of Applied
Cryptography, Alfred J. Menezes, Paul C. van Oorschot and Scott A.
Vanstone. Section 11.2.2 Digital signature schemes with appendix.
Version:
static String | SIGNER_KEY - Property name of the signer's private key.
|
static String | SOURCE_OF_RANDOMNESS - Property name of an optional
java.security.SecureRandom ,
java.util.Random , or IRandom instance to
use.
|
static String | VERIFIER_KEY - Property name of the verifier's public key.
|
Object | clone() - Returns a clone copy of this instance.
|
String | name() - Returns the canonical name of this signature scheme.
|
void | setupSign(Map attributes) - Initialises this instance for signature generation.
|
void | setupVerify(Map attributes) - Initialises this instance for signature verification.
|
Object | sign() - Terminates a signature generation phase by digesting and processing the
context of the underlying message digest algorithm instance.
|
void | update(byte b) - Digests one byte of a message for signing or verification purposes.
|
void | update(byte[] buffer, int offset, int length) - Digests a sequence of bytes from a message for signing or verification
purposes.
|
boolean | verify(Object signature) - Terminates a signature verification phase by digesting and processing
the context of the underlying message digest algorithm instance.
|
SIGNER_KEY
public static final String SIGNER_KEY
Property name of the signer's private key.
SOURCE_OF_RANDOMNESS
public static final String SOURCE_OF_RANDOMNESS
Property name of an optional
java.security.SecureRandom
,
java.util.Random
, or
IRandom
instance to
use. The default is to use a classloader singleton from
PRNG
.
VERIFIER_KEY
public static final String VERIFIER_KEY
Property name of the verifier's public key.
clone
public Object clone()
Returns a clone copy of this instance.
- a clone copy of this instance.
name
public String name()
Returns the canonical name of this signature scheme.
- the canonical name of this instance.
setupSign
public void setupSign(Map attributes)
throws IllegalArgumentException
Initialises this instance for signature generation.
attributes
- the attributes to use for setting up this instance.
SOURCE_OF_RANDOMNESS
, SIGNER_KEY
setupVerify
public void setupVerify(Map attributes)
throws IllegalArgumentException
Initialises this instance for signature verification.
attributes
- the attributes to use for setting up this instance.
SOURCE_OF_RANDOMNESS
, VERIFIER_KEY
sign
public Object sign()
throws IllegalStateException
Terminates a signature generation phase by digesting and processing the
context of the underlying message digest algorithm instance.
- a
Object
representing the native output of the signature
scheme implementation.
update
public void update(byte b)
throws IllegalStateException
Digests one byte of a message for signing or verification purposes.
b
- the message byte to digest.
update
public void update(byte[] buffer,
int offset,
int length)
throws IllegalStateException
Digests a sequence of bytes from a message for signing or verification
purposes.
buffer
- the byte sequence to consider.offset
- the byte poisition in buffer
of the first byte
to consider.length
- the number of bytes in buffer
starting from the
byte at index offset
to digest.
verify
public boolean verify(Object signature)
throws IllegalStateException
Terminates a signature verification phase by digesting and processing
the context of the underlying message digest algorithm instance.
signature
- a native signature object previously generated by an
invocation of the sign()
method.
true
iff the outpout of the verification phase
confirms that the designated signature object has been generated using the
corresponding public key of the recepient.
Copyright © 2001, 2002, 2003
Free Software Foundation,
Inc. All Rights Reserved.