org.bouncycastle.openpgp.operator
Class PBEDataDecryptorFactory

java.lang.Object
  org.bouncycastle.openpgp.operator.PBEDataDecryptorFactory

All Implemented Interfaces:

PGPDataDecryptorFactory

Direct Known Subclasses:

BcPBEDataDecryptorFactory

public abstract class PBEDataDecryptorFactory

extends java.lang.Object

implements PGPDataDecryptorFactory

A factory for performing PBE decryption operations. The purpose of this class is to act as an abstract factory, whose subclasses can decide, which concrete implementation to use for symmetric decryption of SKESK (symmetric-key-encrypted session-key) packets.

Constructor Summary

protected

PBEDataDecryptorFactory(char[] passPhrase, PGPDigestCalculatorProvider calculatorProvider) Construct a PBE data decryptor factory.

Method Summary

byte[]	makeKeyFromPassPhrase(int keyAlgorithm, S2K s2k) Generates an encryption key using the pass phrase and digest calculator configured for this factory.
abstract byte[]	recoverAEADEncryptedSessionData(SymmetricKeyEncSessionPacket keyData, byte[] ikm) Recover the session data of a v5 SKESK or v6 SKESK packet.
abstract byte[]	recoverSessionData(int keyAlgorithm, byte[] key, byte[] seckKeyData) Decrypts session data from a v4 SKESK packet.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.bouncycastle.openpgp.operator.PGPDataDecryptorFactory

createDataDecryptor, createDataDecryptor, createDataDecryptor

Constructor Detail

PBEDataDecryptorFactory

protected PBEDataDecryptorFactory(char[] passPhrase,
                                  PGPDigestCalculatorProvider calculatorProvider)

Construct a PBE data decryptor factory.

Parameters:

passPhrase - the pass phrase to generate decryption keys with.

calculatorProvider - the digest to use in key generation.

Method Detail

makeKeyFromPassPhrase

public byte[] makeKeyFromPassPhrase(int keyAlgorithm,
                                    S2K s2k)
                             throws PGPException

Generates an encryption key using the pass phrase and digest calculator configured for this factory.

Parameters:

keyAlgorithm - the encryption algorithm to generate a key for.

s2k - the string-to-key specification to use to generate the key.

Returns:

the key bytes for the encryption algorithm, generated using the pass phrase of this factory.

Throws:

PGPException - if an error occurs generating the key.

recoverSessionData

public abstract byte[] recoverSessionData(int keyAlgorithm,
                                          byte[] key,
                                          byte[] seckKeyData)
                                   throws PGPException

Decrypts session data from a v4 SKESK packet. These are used in OpenPGP v4.

Parameters:

keyAlgorithm - the encryption algorithm used to encrypt the session data.

key - the key bytes for the encryption algorithm.

seckKeyData - the encrypted session data to decrypt.

Returns:

the decrypted session data.

Throws:

PGPException - if an error occurs decrypting the session data.

recoverAEADEncryptedSessionData

public abstract byte[] recoverAEADEncryptedSessionData(SymmetricKeyEncSessionPacket keyData,
                                                       byte[] ikm)
                                                throws PGPException

Recover the session data of a v5 SKESK or v6 SKESK packet. These are used in OpenPGP v5 and v6.

Parameters:

keyData - v5 or v6 SKESK packet

ikm - initial keying material (e.g. S2K result)

Returns:

session key

Throws:

PGPException