P256K
P256K
P256K.MuSig
P256K.MuSig.XonlyKey

Structure

P256K.MuSig.XonlyKey

The 32-byte x-only form of a MuSig2 aggregate public key, used for BIP-340 Schnorr signature verification and Taproot tweaking via add(_:).

iOS 13.0+
macCatalyst 13.0+
macOS 10.15+
tvOS 13.0+
visionOS 1.0+
watchOS 6.0+

struct XonlyKey

Overview

X-only keys drop the Y-coordinate parity bit from the standard 33-byte compressed encoding, matching the representation BIP-340 verifiers consume directly. The 1-bit parity is retained separately as parity so Taproot tweak verification can reconstruct the full point when computing t * G and the subsequent conditional negation.

Topics

Inspection

Reconstruction

init<D>(dataRepresentation: D, keyParity: Int32, cache: [UInt8])
Creates a MuSig x-only public key from 32-byte serialized data and a preserved key aggregation cache.

Operators

static func == (P256K.MuSig.XonlyKey, P256K.MuSig.XonlyKey) -> Bool
Returns true if both x-only keys have identical 32-byte X coordinates.

Instance Methods

func add([UInt8]) throws -> P256K.MuSig.XonlyKey
Creates a new P256K.MuSig.XonlyKey by computing agg_pk' = agg_pk + G × tweak via secp256k1_musig_pubkey_xonly_tweak_add, as required for BIP-341 Taproot output key construction.
func isValid(P256K.MuSig.AggregateSignature, for: inout [UInt8]) -> Bool
Verifies a MuSig2 aggregate signature over an arbitrary-length message using secp256k1_schnorrsig_verify.
func isValidSignature<D>(P256K.MuSig.AggregateSignature, for: D) -> Bool
Verifies a MuSig2 P256K.MuSig.AggregateSignature against a pre-computed digest using secp256k1_schnorrsig_verify.