Class Secp256k1.EcdsaSignature

java.lang.Object

com.codename1.security.Secp256k1.EcdsaSignature

Enclosing class:

Secp256k1

public static final class Secp256k1.EcdsaSignature
extends Object

An ECDSA signature: r and s as 32-byte big-endian integers, and the recovery id a signer knows and a verifier does not need.

Constructor Summary

Constructors

Constructor	Description
EcdsaSignature(byte[] r, byte[] s, int recoveryId)	Creates a signature from its parts.

Method Summary

Modifier and Type	Method	Description
static Secp256k1.EcdsaSignature	fromCompact(byte[] compact, int recoveryId)	Creates a signature from the 64-byte r || s encoding.
boolean	isLowS()	Tells whether s is in the lower half of the range, the form Secp256k1.sign(byte[], byte[]) produces and Secp256k1.verify(byte[], Secp256k1.EcdsaSignature, byte[]) accepts.
Secp256k1.EcdsaSignature	normalize()	Returns the signature with s lowered to the other half of the range when it is high, flipping the recovery id to match; a signature that is already low-S is returned as it is.
byte[]	r()	The r component, 32 big-endian bytes.
int	recoveryId()	The recovery id, 0 to 3, or -1 when the signature was built without one.
byte[]	s()	The s component, 32 big-endian bytes.
byte[]	toCompact()	The 64-byte r || s encoding.

Methods inherited from class Object

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

Constructor Details

EcdsaSignature

public EcdsaSignature(byte[] r,
 byte[] s,
 int recoveryId)

Creates a signature from its parts.

Parameters

• r: 32 bytes

• s: 32 bytes

• recoveryId: 0 to 3, or -1 when it is not known

Throws

• CryptoException: if a part has the wrong length or the recovery id is out of range

Method Details

fromCompact

public static Secp256k1.EcdsaSignature fromCompact(byte[] compact,
 int recoveryId)

Creates a signature from the 64-byte r || s encoding.

Parameters

• compact: 64 bytes, r then s

• recoveryId: 0 to 3, or -1 when it is not known

r

public byte[] r()

The r component, 32 big-endian bytes.

s

public byte[] s()

The s component, 32 big-endian bytes.

recoveryId

public int recoveryId()

The recovery id, 0 to 3, or -1 when the signature was built without one. Ethereum's v is this plus 27, or plus chainId * 2 + 35 under EIP-155.

toCompact

public byte[] toCompact()

The 64-byte r || s encoding.

isLowS

public boolean isLowS()

Tells whether s is in the lower half of the range, the form Secp256k1.sign(byte[], byte[]) produces and Secp256k1.verify(byte[], Secp256k1.EcdsaSignature, byte[]) accepts.

normalize

public Secp256k1.EcdsaSignature normalize()

Returns the signature with s lowered to the other half of the range when it is high, flipping the recovery id to match; a signature that is already low-S is returned as it is. Both forms are valid for the same key and hash, which is why networks accept only one of them.