gnu.crypto.sig
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:
Version: $Revision: 1.8 $
Field Summary | |
---|---|
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. |
Method Summary | |
---|---|
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. |
Returns a clone copy of this instance.
Returns: a clone copy of this instance.
Returns the canonical name of this signature scheme.
Returns: the canonical name of this instance.
Initialises this instance for signature generation.
Parameters: attributes the attributes to use for setting up this instance.
Throws: IllegalArgumentException if the designated private key is not appropriate for this signature scheme.
See Also: SOURCE_OF_RANDOMNESS SIGNER_KEY
Initialises this instance for signature verification.
Parameters: attributes the attributes to use for setting up this instance.
Throws: IllegalArgumentException if the designated public key is not appropriate for this signature scheme.
See Also: SOURCE_OF_RANDOMNESS VERIFIER_KEY
Terminates a signature generation phase by digesting and processing the context of the underlying message digest algorithm instance.
Returns: a Object representing the native output of the signature scheme implementation.
Throws: IllegalStateException if this instance was not setup for signature generation.
Digests one byte of a message for signing or verification purposes.
Parameters: b the message byte to digest.
Throws: IllegalStateException if this instance was not setup for signature generation/verification.
Digests a sequence of bytes from a message for signing or verification purposes.
Parameters: 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.
Throws: IllegalStateException if this instance was not setup for signature generation/verification.
Terminates a signature verification phase by digesting and processing the context of the underlying message digest algorithm instance.
Parameters: signature a native signature object previously generated by an
invocation of the sign()
method.
Returns: 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.
Throws: IllegalStateException if this instance was not setup for signature verification.