gnu.crypto.key.srp6

Class SRPKeyPairRawCodec

Implemented Interfaces:
IKeyPairCodec

public class SRPKeyPairRawCodec
extends 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 $

Fields inherited from interface gnu.crypto.key.IKeyPairCodec

RAW_FORMAT

Method Summary

PrivateKey
decodePrivateKey(byte[] k)
Decodes an instance of an external private key into its native Java representation.
PublicKey
decodePublicKey(byte[] k)
Decodes an instance of an external public key into its native Java representation.
byte[]
encodePrivateKey(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,
  2. 1-byte version consisting of the constant: 0x01,
  3. 4-byte count of following bytes representing the SRP parameter N in internet order,
  4. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter N,
  5. 4-byte count of following bytes representing the SRP parameter g,
  6. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter g,
  7. 4-byte count of following bytes representing the SRP parameter x,
  8. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter x,
  9. one byte which indicates whether the SRP parameter v is included in this encoding (value 0x01) or not (value 0x00).
  10. 4-byte count of following bytes representing the SRP parameter v,
  11. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter v,
byte[]
encodePublicKey(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,
  2. 1-byte version consisting of the constant: 0x01,
  3. 4-byte count of following bytes representing the SRP parameter N in internet order,
  4. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter N,
  5. 4-byte count of following bytes representing the SRP parameter g,
  6. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter g,
  7. 4-byte count of following bytes representing the SRP parameter y,
  8. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter y,
int
getFormatID()
Returns the unique identifier (within this library) of the format used to externalise public and private keys.

Method Details

decodePrivateKey

public PrivateKey decodePrivateKey(byte[] k)
Decodes an instance of an external private key into its native Java representation.
Specified by:
decodePrivateKey in interface IKeyPairCodec
Parameters:
Returns:
a concrete instance of a private key, reconstructed from the designated input.

decodePublicKey

public PublicKey decodePublicKey(byte[] k)
Decodes an instance of an external public key into its native Java representation.
Specified by:
decodePublicKey in interface IKeyPairCodec
Parameters:
Returns:
a concrete instance of a public key, reconstructed from the designated input.

encodePrivateKey

public byte[] encodePrivateKey(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,
  2. 1-byte version consisting of the constant: 0x01,
  3. 4-byte count of following bytes representing the SRP parameter N in internet order,
  4. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter N,
  5. 4-byte count of following bytes representing the SRP parameter g,
  6. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter g,
  7. 4-byte count of following bytes representing the SRP parameter x,
  8. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter x,
  9. one byte which indicates whether the SRP parameter v is included in this encoding (value 0x01) or not (value 0x00).
  10. 4-byte count of following bytes representing the SRP parameter v,
  11. 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.

encodePublicKey

public byte[] encodePublicKey(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,
  2. 1-byte version consisting of the constant: 0x01,
  3. 4-byte count of following bytes representing the SRP parameter N in internet order,
  4. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter N,
  5. 4-byte count of following bytes representing the SRP parameter g,
  6. n-bytes representation of a BigInteger obtained by invoking the toByteArray() method on the SRP parameter g,
  7. 4-byte count of following bytes representing the SRP parameter y,
  8. 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.

getFormatID

public int getFormatID()
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.

Copyright © 2001, 2002, 2003 Free Software Foundation, Inc. All Rights Reserved.