Top Description Fields Constructors Methods

org.apache.sshd.common.kex

public final Enum MontgomeryCurve

Class Inheritance

extends Enum<MontgomeryCurve>
implements KeySizeIndicator, CurveSizeIndicator, OptionalFeature

java.lang.Object
java.lang.Enum
org.apache.sshd.common.kex.MontgomeryCurve

All Implemented Interfaces

org.apache.sshd.common.OptionalFeature, org.apache.sshd.common.kex.CurveSizeIndicator, org.apache.sshd.common.keyprovider.KeySizeIndicator

Imports

java.security.GeneralSecurityException, .InvalidKeyException, .KeyFactory, .KeyPair, .KeyPairGenerator, .PublicKey, java.security.spec.InvalidKeySpecException, .X509EncodedKeySpec, java.util.Arrays, javax.crypto.KeyAgreement, org.apache.sshd.common.OptionalFeature, org.apache.sshd.common.keyprovider.KeySizeIndicator, org.apache.sshd.common.util.security.SecurityUtils

Provides implementation details for Montgomery curves and their key exchange algorithms Curve25519/X25519 and Curve448/X448 specified in RFC 7748 and RFC 8731. Montgomery curves provide improved security and flexibility over Weierstrass curves used in ECDH.

See Also: RFC 7748, RFC 8731

Field Summary

Modifier and Type	Field and Description
private final String	algorithm
private final byte[]	encodedPublicKeyPrefix
private final KeyFactory	keyFactory
private final KeyPairGenerator	keyPairGenerator
private final int	keySize
private final boolean	supported
public static final MontgomeryCurve	x25519 X25519 uses Curve25519 and SHA-256 with a 32-byte key size.
public static final MontgomeryCurve	x448 X448 uses Curve448 and SHA-512 with a 56-byte key size.

Constructor Summary

Access	Constructor and Description
private	MontgomeryCurve(String algorithm, int keySize, byte[] encodedPublicKeyPrefix)

Method Summary

Modifier and Type	Method and Description
public KeyAgreement	createKeyAgreement()
public PublicKey	decode(byte[] key)
public byte[]	encode(PublicKey key)
public KeyPair	generateKeyPair()
public String	getAlgorithm()
public int	getByteLength() Implements org.apache.sshd.common.kex.CurveSizeIndicator.getByteLength. Retrieves the length of a point coordinate in bytes.
public int	getKeySize() Implements org.apache.sshd.common.keyprovider.KeySizeIndicator.getKeySize.
public boolean	isSupported() Implements org.apache.sshd.common.OptionalFeature.isSupported.
public static MontgomeryCurve	valueOf(String name)
public static MontgomeryCurve[]	values()

Inherited from java.lang.Enum:: clone compareTo describeConstable equals finalize getDeclaringClass hashCode name ordinal toString valueOf

Field Detail

algorithm	back to summary
private final String algorithm

encodedPublicKeyPrefix	back to summary
private final byte[] encodedPublicKeyPrefix

keyFactory	back to summary
private final KeyFactory keyFactory

keyPairGenerator	back to summary
private final KeyPairGenerator keyPairGenerator

keySize	back to summary
private final int keySize

supported	back to summary
private final boolean supported

x25519	back to summary
public static final MontgomeryCurve x25519 X25519 uses Curve25519 and SHA-256 with a 32-byte key size.

x448	back to summary
public static final MontgomeryCurve x448 X448 uses Curve448 and SHA-512 with a 56-byte key size.

Constructor Detail

MontgomeryCurve	back to summary
private MontgomeryCurve(String algorithm, int keySize, byte[] encodedPublicKeyPrefix)

Method Detail

createKeyAgreement	back to summary
public KeyAgreement createKeyAgreement() throws GeneralSecurityException

decode	back to summary
public PublicKey decode(byte[] key) throws InvalidKeySpecException

encode	back to summary
public byte[] encode(PublicKey key) throws InvalidKeyException

generateKeyPair	back to summary
public KeyPair generateKeyPair()

getAlgorithm	back to summary
public String getAlgorithm()

getByteLength

back to summary

public int getByteLength()

Implements org.apache.sshd.common.kex.CurveSizeIndicator.getByteLength.

Doc from org.apache.sshd.common.kex.CurveSizeIndicator.getByteLength.

Retrieves the length of a point coordinate in bytes.

Returns:int

the length

Annotations

@Override

getKeySize

back to summary

public int getKeySize()

Implements org.apache.sshd.common.keyprovider.KeySizeIndicator.getKeySize.

Returns:int

Doc from org.apache.sshd.common.keyprovider.KeySizeIndicator.getKeySize.

The number of bits used in the key

Annotations

@Override

isSupported

back to summary

public boolean isSupported()

Implements org.apache.sshd.common.OptionalFeature.isSupported.

Annotations

@Override

valueOf	back to summary
public static MontgomeryCurve valueOf(String name)

values	back to summary
public static MontgomeryCurve[] values()