org.web3j.crypto

Class ECDSASignature

java.lang.Object

org.web3j.crypto.ECDSASignature

public class ECDSASignature
extends java.lang.Object

An ECDSA Signature.

Field Summary

Fields

Modifier and Type	Field and Description
java.math.BigInteger	r
java.math.BigInteger	s

Constructor Summary

Constructors

Constructor and Description
ECDSASignature(java.math.BigInteger r, java.math.BigInteger s)

Method Summary

Modifier and Type	Method and Description
boolean	isCanonical()
ECDSASignature	toCanonicalised() Will automatically adjust the S component to be less than or equal to half the curve order, if necessary.

Methods inherited from class java.lang.Object

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

Field Detail

r

public final java.math.BigInteger r

s

public final java.math.BigInteger s

Constructor Detail

ECDSASignature

public ECDSASignature(java.math.BigInteger r,
                      java.math.BigInteger s)

Method Detail

isCanonical

public boolean isCanonical()

Returns:

true if the S component is "low", that means it is below Sign.HALF_CURVE_ORDER. See BIP62.

toCanonicalised

public ECDSASignature toCanonicalised()

Will automatically adjust the S component to be less than or equal to half the curve order, if necessary. This is required because for every signature (r,s) the signature (r, -s (mod N)) is a valid signature of the same message. However, we dislike the ability to modify the bits of a Bitcoin transaction after it's been signed, as that violates various assumed invariants. Thus in future only one of those forms will be considered legal and the other will be banned.

Returns:

the signature in a canonicalised form.