org.whispersystems.curve25519

Class Curve25519

java.lang.Object

org.whispersystems.curve25519.Curve25519

public class Curve25519
extends java.lang.Object

A Curve25519 interface for generating keys, calculating agreements, creating signatures, and verifying signatures.

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	BEST
static java.lang.String	J2ME
static java.lang.String	JAVA
static java.lang.String	NATIVE

Method Summary

Modifier and Type	Method and Description
byte[]	calculateAgreement(byte[] publicKey, byte[] privateKey) Calculates an ECDH agreement.
byte[]	calculateSignature(byte[] privateKey, byte[] message) Calculates a Curve25519 signature.
Curve25519KeyPair	generateKeyPair() Generates a Curve25519 keypair.
static Curve25519	getInstance(java.lang.String type)
static Curve25519	getInstance(java.lang.String type, SecureRandomProvider random)
boolean	isNative() Curve25519 is backed by either a native (via JNI) or pure-Java provider.
boolean	verifySignature(byte[] publicKey, byte[] message, byte[] signature) Verify a Curve25519 signature.

Methods inherited from class java.lang.Object

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

Field Detail

NATIVE

public static final java.lang.String NATIVE

See Also:

Constant Field Values

JAVA

public static final java.lang.String JAVA

See Also:

Constant Field Values

J2ME

public static final java.lang.String J2ME

See Also:

Constant Field Values

BEST

public static final java.lang.String BEST

See Also:

Constant Field Values

Method Detail

getInstance

public static Curve25519 getInstance(java.lang.String type)
                              throws NoSuchProviderException

Throws:

NoSuchProviderException

getInstance

public static Curve25519 getInstance(java.lang.String type,
                                     SecureRandomProvider random)
                              throws NoSuchProviderException

Throws:

NoSuchProviderException

isNative

public boolean isNative()

Curve25519 is backed by either a native (via JNI) or pure-Java provider. By default it prefers the native provider, and falls back to the pure-Java provider if the native library fails to load.

Returns:

true if backed by a native provider, false otherwise.

generateKeyPair

public Curve25519KeyPair generateKeyPair()

Generates a Curve25519 keypair.

Returns:

A randomly generated Curve25519 keypair.

calculateAgreement

public byte[] calculateAgreement(byte[] publicKey,
                                 byte[] privateKey)

Calculates an ECDH agreement.

Parameters:

publicKey - The Curve25519 (typically remote party's) public key.

privateKey - The Curve25519 (typically yours) private key.

Returns:

A 32-byte shared secret.

calculateSignature

public byte[] calculateSignature(byte[] privateKey,
                                 byte[] message)

Calculates a Curve25519 signature.

Parameters:

privateKey - The private Curve25519 key to create the signature with.

message - The message to sign.

Returns:

A 64-byte signature.

verifySignature

public boolean verifySignature(byte[] publicKey,
                               byte[] message,
                               byte[] signature)

Verify a Curve25519 signature.

Parameters:

publicKey - The Curve25519 public key the signature belongs to.

message - The message that was signed.

signature - The signature to verify.

Returns:

true if valid, false if not.