Package org.bouncycastle.bcpg

Class S2K

java.lang.Object

org.bouncycastle.bcpg.BCPGObject

org.bouncycastle.bcpg.S2K

All Implemented Interfaces:

org.bouncycastle.util.Encodable

public class S2K
extends BCPGObject

Parameter specifier for the PGP string-to-key password based key derivation function.

In iterated mode, S2K takes a single byte iteration count specifier, which is converted to an actual iteration count using a formula that grows the iteration count exponentially as the byte value increases.

e.g. 0x01 == 1088 iterations, and 0xFF == 65,011,712 iterations.

Field Summary

Fields

Modifier and Type	Field	Description
static final int	GNU_DUMMY_S2K
static final int	GNU_PROTECTION_MODE_DIVERT_TO_CARD
static final int	GNU_PROTECTION_MODE_NO_PRIVATE_KEY
static final int	SALTED	Salted key generation.
static final int	SALTED_AND_ITERATED	Salted and iterated key generation.
static final int	SIMPLE	Simple key generation.

Constructor Summary

Constructors

Constructor	Description
S2K(int algorithm)	Constructs a specifier for a simple S2K generation.
S2K(int algorithm, byte[] iv)	Constructs a specifier for a salted S2K generation.
S2K(int algorithm, byte[] iv, int itCount)	Constructs a specifier for a salted and iterated S2K generation.

Method Summary

Modifier and Type	Method	Description
void	encode(BCPGOutputStream out)
int	getHashAlgorithm()	Gets the hash algorithm for this S2K.
long	getIterationCount()	Gets the actual (expanded) iteration count.
byte[]	getIV()	Gets the iv/salt to use for the key generation.
int	getProtectionMode()	Gets the protection mode - only if GNU_DUMMY_S2K
int	getType()	Gets the digest algorithm specified.

Methods inherited from class org.bouncycastle.bcpg.BCPGObject

getEncoded

Methods inherited from class java.lang.Object

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

Field Details

SIMPLE

public static final int SIMPLE

Simple key generation. A single non-salted iteration of a hash function

See Also:

• Constant Field Values

SALTED

public static final int SALTED

Salted key generation. A single iteration of a hash function with a (unique) salt

See Also:

• Constant Field Values

SALTED_AND_ITERATED

public static final int SALTED_AND_ITERATED

Salted and iterated key generation. Multiple iterations of a hash function, with a salt

See Also:

• Constant Field Values

GNU_DUMMY_S2K

public static final int GNU_DUMMY_S2K

See Also:

• Constant Field Values

GNU_PROTECTION_MODE_NO_PRIVATE_KEY

public static final int GNU_PROTECTION_MODE_NO_PRIVATE_KEY

See Also:

• Constant Field Values

GNU_PROTECTION_MODE_DIVERT_TO_CARD

public static final int GNU_PROTECTION_MODE_DIVERT_TO_CARD

See Also:

• Constant Field Values

Constructor Details

S2K

public S2K(int algorithm)

Constructs a specifier for a simple S2K generation.

Parameters:

algorithm - the digest algorithm to use.

S2K

public S2K(int algorithm,
 byte[] iv)

Constructs a specifier for a salted S2K generation.

Parameters:

algorithm - the digest algorithm to use.

iv - the salt to apply to input to the key generation.

S2K

public S2K(int algorithm,
 byte[] iv,
 int itCount)

Constructs a specifier for a salted and iterated S2K generation.

Parameters:

algorithm - the digest algorithm to iterate.

iv - the salt to apply to input to the key generation.

itCount - the single byte iteration count specifier.

Method Details

getType

public int getType()

Gets the digest algorithm specified.

getHashAlgorithm

public int getHashAlgorithm()

Gets the hash algorithm for this S2K.

getIV

public byte[] getIV()

Gets the iv/salt to use for the key generation.

getIterationCount

public long getIterationCount()

Gets the actual (expanded) iteration count.

getProtectionMode

public int getProtectionMode()

Gets the protection mode - only if GNU_DUMMY_S2K

encode

public void encode(BCPGOutputStream out)
            throws IOException

Specified by:

encode in class BCPGObject

Throws:

IOException