net.i2p.crypto.eddsa.math.bigint

Class BigIntegerScalarOps

java.lang.Object

net.i2p.crypto.eddsa.math.bigint.BigIntegerScalarOps

All Implemented Interfaces:

ScalarOps

public class BigIntegerScalarOps
extends Object
implements ScalarOps

Constructor Summary

Constructors

Constructor and Description
BigIntegerScalarOps(Field f, BigInteger l)

Method Summary

Methods

Modifier and Type	Method and Description
byte[]	multiplyAndAdd(byte[] a, byte[] b, byte[] c) r = (a * b + c) mod l
byte[]	reduce(byte[] s) Reduce the given scalar mod l.

Methods inherited from class java.lang.Object

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

Constructor Detail

BigIntegerScalarOps

public BigIntegerScalarOps(Field f,
                   BigInteger l)

Method Detail

reduce

public byte[] reduce(byte[] s)

Description copied from interface: ScalarOps

Reduce the given scalar mod l.

From the Ed25519 paper:
Here we interpret 2b-bit strings in little-endian form as integers in {0, 1,..., 2^(2b)-1}.

Specified by:

reduce in interface ScalarOps

Returns:

s mod l

multiplyAndAdd

public byte[] multiplyAndAdd(byte[] a,
                    byte[] b,
                    byte[] c)

Description copied from interface: ScalarOps

r = (a * b + c) mod l

Specified by:

multiplyAndAdd in interface ScalarOps

Returns:

(a*b + c) mod l