gnu.crypto.key.srp6
Class SRPKeyPairRawCodec

java.lang.Object
  gnu.crypto.key.srp6.SRPKeyPairRawCodec

All Implemented Interfaces:

IKeyPairCodec

public class SRPKeyPairRawCodec

extends java.lang.Object

implements IKeyPairCodec

An object that implements the IKeyPairCodec operations for the Raw format to use with SRP keypairs.

Reference:

1. SRP Protocol Design
   Thomas J. Wu.

Version:

$Revision: 1.2 $

Field Summary

Fields inherited from interface gnu.crypto.key.IKeyPairCodec

RAW_FORMAT

Constructor Summary

SRPKeyPairRawCodec()

Method Summary

java.security.PrivateKey	decodePrivateKey(byte[] k) Decodes an instance of an external private key into its native Java representation.
java.security.PublicKey	decodePublicKey(byte[] k) Decodes an instance of an external public key into its native Java representation.
byte[]	encodePrivateKey(java.security.PrivateKey key) Returns the encoded form of the designated SRP private key according to the Raw format supported by this library.
byte[]	encodePublicKey(java.security.PublicKey key) Returns the encoded form of the designated SRP public key according to the Raw format supported by this library.
int	getFormatID() Returns the unique identifier (within this library) of the format used to externalise public and private keys.

Methods inherited from class java.lang.Object

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

Constructor Detail

SRPKeyPairRawCodec

public SRPKeyPairRawCodec()

Method Detail

getFormatID

public int getFormatID()

Description copied from interface: IKeyPairCodec

Returns the unique identifier (within this library) of the format used to externalise public and private keys.

Specified by:

getFormatID in interface IKeyPairCodec

Returns:

the identifier of the format, the object supports.

encodePublicKey

public byte[] encodePublicKey(java.security.PublicKey key)

Returns the encoded form of the designated SRP public key according to the Raw format supported by this library.

The Raw format for an SRP public key, in this implementation, is a byte sequence consisting of the following:

1. 4-byte magic consisting of the value of the literal Registry.MAGIC_RAW_SRP_PUBLIC_KEY,
3. 1-byte version consisting of the constant: 0x01,
4. 4-byte count of following bytes representing the SRP parameter N in internet order,
5. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter N,
6. 4-byte count of following bytes representing the SRP parameter g,
7. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter g,
8. 4-byte count of following bytes representing the SRP parameter y,
9. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter y,

Specified by:

encodePublicKey in interface IKeyPairCodec

Parameters:

key - the key to encode.

Returns:

the Raw format encoding of the designated key.

Throws:

java.lang.IllegalArgumentException - if the designated key is not an SRP one.

decodePublicKey

public java.security.PublicKey decodePublicKey(byte[] k)

Description copied from interface: IKeyPairCodec

Decodes an instance of an external public key into its native Java representation.

Specified by:

decodePublicKey in interface IKeyPairCodec

Parameters:

k - the source of the externalised key to decode.

Returns:

a concrete instance of a public key, reconstructed from the designated input.

encodePrivateKey

public byte[] encodePrivateKey(java.security.PrivateKey key)

Returns the encoded form of the designated SRP private key according to the Raw format supported by this library.

The Raw format for an SRP private key, in this implementation, is a byte sequence consisting of the following:

1. 4-byte magic consisting of the value of the literal Registry.MAGIC_RAW_SRP_PRIVATE_KEY,
3. 1-byte version consisting of the constant: 0x01,
4. 4-byte count of following bytes representing the SRP parameter N in internet order,
5. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter N,
6. 4-byte count of following bytes representing the SRP parameter g,
7. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter g,
8. 4-byte count of following bytes representing the SRP parameter x,
9. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter x,
10. one byte which indicates whether the SRP parameter v is included in this encoding (value 0x01) or not (value 0x00).
11. 4-byte count of following bytes representing the SRP parameter v,
12. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter v,

Specified by:

encodePrivateKey in interface IKeyPairCodec

Parameters:

key - the key to encode.

Returns:

the Raw format encoding of the designated key.

Throws:

java.lang.IllegalArgumentException - if the designated key is not an SRP one.

decodePrivateKey

public java.security.PrivateKey decodePrivateKey(byte[] k)

Description copied from interface: IKeyPairCodec

Decodes an instance of an external private key into its native Java representation.

Specified by:

decodePrivateKey in interface IKeyPairCodec

Parameters:

k - the source of the externalised key to decode.

Returns:

a concrete instance of a private key, reconstructed from the designated input.