java.security
Class SignatureSpi
SignatureSpi defines the Service Provider Interface (SPI) for
the
Signature class. The signature class provides an interface to a
digital signature algorithm. Digital signatures are used for authentication
and integrity of data.
clone, equals, extends Object> getClass, finalize, hashCode, notify, notifyAll, toString, wait, wait, wait |
SignatureSpi
public SignatureSpi()
Creates a new instance of SignatureSpi.
engineInitSign
protected void engineInitSign(PrivateKey privateKey,
SecureRandom random)
throws InvalidKeyException Initializes this instance with the private key and source of randomness for
signing purposes.
This method cannot be abstract for backward compatibility reasons.
privateKey - the private key to sign with.random - the SecureRandom to use.
engineInitVerify
protected abstract void engineInitVerify(PublicKey publicKey)
throws InvalidKeyException Initializes this instance with the public key for verification purposes.
publicKey - the public key to verify with.
engineSetParameter
protected abstract void engineSetParameter(String param,
Object value)
throws InvalidParameterExceptionuse the other setParameter.
Sets the specified algorithm parameter to the specified value.
param - the parameter name.value - the parameter value.
InvalidParameterException - if the parameter invalid, the parameter is already set and
cannot be changed, a security exception occured, etc.
engineSign
protected abstract byte[] engineSign()
throws SignatureException Returns the signature bytes of all the data fed to this instance. The
format of the output depends on the underlying signature algorithm.
engineSign
protected int engineSign(byte[] outbuf,
int offset,
int len)
throws SignatureException Generates signature bytes of all the data fed to this instance and stores
the result in the designated array. The format of the output depends on
the underlying signature algorithm.
This method cannot be abstract for backward compatibility reasons.
After calling this method, the signature is reset to its initial state and
can be used to generate additional signatures.
IMPLEMENTATION NOTE:: Neither this method nor the GNU provider
will return partial digests. If
len is less than the
signature length, this method will throw a
SignatureException. If
it is greater than or equal then it is ignored.
outbuf - the array of bytes to store the result in.offset - the offset to start at in the array.len - the number of the bytes to use in the array.
- the real number of bytes used.
engineUpdate
protected abstract void engineUpdate(byte[] b,
int off,
int len)
throws SignatureException Updates the data to be signed or verified with the specified bytes.
b - the array of bytes to use.off - the offset to start at in the array.len - the number of the bytes to use from the array.
engineVerify
protected abstract boolean engineVerify(byte[] sigBytes)
throws SignatureException Verifies a designated signature.
sigBytes - the signature bytes to verify.
true if verified, false otherwise.
SignatureException - if the engine is not properly initialized or if it is the wrong
signature.
engineVerify
protected boolean engineVerify(byte[] sigBytes,
int offset,
int length)
throws SignatureException Convenience method which calls the method with the same name and one
argument after copying the designated bytes into a temporary byte array.
Subclasses may override this method for performance reasons.
sigBytes - the array of bytes to use.offset - the offset to start from in the array of bytes.length - the number of bytes to use, starting at offset.
true if verified, false otherwise.
SignatureSpi.java --- Signature Service Provider Interface
Copyright (C) 1999, 2003, Free Software Foundation, Inc.
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