org.bouncycastle.crypto.params

Class XMSSParameters

java.lang.Object

org.bouncycastle.crypto.params.XMSSParameters

All Implemented Interfaces:

PQCParameters

public final class XMSSParameters
extends java.lang.Object
implements PQCParameters

XMSS Parameters.

Field Summary

Fields

Modifier and Type	Field and Description
static int	MAX_HEIGHT The tallest tree whose leaves an int index can count.

Constructor Summary

Constructors

Constructor and Description
XMSSParameters(int height, ASN1ObjectIdentifier treeDigestOID) XMSS Constructor...
XMSSParameters(int height, ASN1ObjectIdentifier treeDigestOID, int n) XMSS Constructor with explicit security parameter n.
XMSSParameters(int height, Digest treeDigest) XMSS Constructor...

Method Summary

Modifier and Type	Method and Description
int	getClassicalSecurityStrength() Return the classical security strength of this parameter set: 8 times the hash output length n, capped at 256 bits, or at 128 bits for SHAKE128 (NIST IR 8547, Table 3).
int	getHeight() Getter height.
int	getK()
int	getLen()
int	getParameterSetOID() Return the RFC 8391 / SP 800-208 parameter-set identifier for this parameter set (the 4-octet value carried at the start of an RFC 9802 encoded key), or 0 if these parameters do not correspond to a standard set (for example a non-standard tree height).
int	getSecurityCategory() Return the NIST security category of this parameter set: 3 for the SHA-256/192 and SHAKE256/192 sets (n = 24) and 5 for the SHA-256 and SHAKE256/256 sets (n = 32) (NIST IR 8547, Table 3, for the sets approved in SP 800-208).
java.lang.String	getTreeDigest()
ASN1ObjectIdentifier	getTreeDigestOID() Return the tree digest OID.
int	getTreeDigestSize() Getter digest size.
int	getWinternitzParameter() Getter Winternitz parameter.
static XMSSParameters	lookupByOID(int oid)

Methods inherited from class java.lang.Object

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

Field Detail

MAX_HEIGHT

public static final int MAX_HEIGHT

The tallest tree whose leaves an int index can count. Shared with BDS.validate(), which refuses a traversal state outside it.

See Also:

Constant Field Values

Constructor Detail

XMSSParameters

public XMSSParameters(int height,
                      Digest treeDigest)

XMSS Constructor...

Parameters:

height - Height of tree.

treeDigest - Digest to use.

XMSSParameters

public XMSSParameters(int height,
                      ASN1ObjectIdentifier treeDigestOID)

XMSS Constructor...

Parameters:

height - Height of tree.

treeDigestOID - OID of digest to use.

XMSSParameters

public XMSSParameters(int height,
                      ASN1ObjectIdentifier treeDigestOID,
                      int n)

XMSS Constructor with explicit security parameter n.

Parameters:

height - Height of tree.

treeDigestOID - OID of digest to use.

n - Security parameter (digest output size in bytes), or -1 to derive from digest.

Method Detail

getTreeDigestSize

public int getTreeDigestSize()

Getter digest size.

Returns:

Digest size.

getSecurityCategory

public int getSecurityCategory()

Return the NIST security category of this parameter set: 3 for the SHA-256/192 and SHAKE256/192 sets (n = 24) and 5 for the SHA-256 and SHAKE256/256 sets (n = 32) (NIST IR 8547, Table 3, for the sets approved in SP 800-208). The RFC 8391 sets outside SP 800-208 carry no NIST categorisation and are given the figure their hash implies: 5 for SHA-512 and SHAKE256/512, and 1 for SHAKE128, whose security is capped at 128 bits whatever its output length.

Specified by:

getSecurityCategory in interface PQCParameters

Returns:

the security category, as given in NIST IR 8547 Tables 3 and 5.

getClassicalSecurityStrength

public int getClassicalSecurityStrength()

Return the classical security strength of this parameter set: 8 times the hash output length n, capped at 256 bits, or at 128 bits for SHAKE128 (NIST IR 8547, Table 3).

Specified by:

getClassicalSecurityStrength in interface PQCParameters

Returns:

the classical security strength in bits.

getTreeDigestOID

public ASN1ObjectIdentifier getTreeDigestOID()

Return the tree digest OID.

Returns:

OID for digest used to build the tree.

getParameterSetOID

public int getParameterSetOID()

Return the RFC 8391 / SP 800-208 parameter-set identifier for this parameter set (the 4-octet value carried at the start of an RFC 9802 encoded key), or 0 if these parameters do not correspond to a standard set (for example a non-standard tree height).

Returns:

the 4-octet parameter-set identifier, or 0 if none.

getHeight

public int getHeight()

Getter height.

Returns:

XMSS tree height.

getTreeDigest

public java.lang.String getTreeDigest()

getLen

public int getLen()

getWinternitzParameter

public int getWinternitzParameter()

Getter Winternitz parameter.

Returns:

Winternitz parameter.

getK

public int getK()

lookupByOID

public static XMSSParameters lookupByOID(int oid)