P256K
P256K
P256K.Signing
P256K.Signing.PrivateKey

Structure

P256K.Signing.PrivateKey

secp256k1 ECDSA private key for deterministically signing messages and producing P256K.Signing.ECDSASignature values using the secp256k1 curve.

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

struct PrivateKey

Mentioned In

Overview

Create a key by generating fresh randomness or by deserializing an existing raw, PEM, or DER representation. The 32-byte secret scalar must pass secp256k1_ec_seckey_verify (declared in Vendor/secp256k1/include/secp256k1.h) to be accepted. Keep dataRepresentation confidential; exposing it compromises all signatures produced by this key.

The format parameter controls whether the public key companion is serialized as compressed (33 bytes, default) or uncompressed (65 bytes). The private key itself is always 32 bytes regardless of format.

Signing

ECDSA signing uses secp256k1_ecdsa_sign with RFC 6979 deterministic nonce generation. All signatures produced by this key are automatically normalized to lower-S form per BIP-146, which is the only form accepted by secp256k1_ecdsa_verify. Pass a Digest or raw Data to the signature(for:) overloads on this type; the data overload hashes with SHA-256 before signing.

Topics

Construction

Inspection

var publicKey: P256K.Signing.PublicKey
The secp256k1 public key derived from this private key, used to verify signatures this key produces.
var dataRepresentation: Data
The raw 32-byte secret key as Data. Keep this value confidential; disclosure allows anyone to sign on your behalf.
var negation: P256K.Signing.PrivateKey
A new P256K.Signing.PrivateKey whose secret scalar is the additive inverse of this key modulo the secp256k1 curve order, produced by secp256k1_ec_seckey_negate.

Operators

static func == (P256K.Signing.PrivateKey, P256K.Signing.PrivateKey) -> Bool
Returns true if both private keys have identical 32-byte secret scalars; compares using SecureBytes constant-time equality.

Initializers

init(UInt256, format: P256K.Format) throws
Creates a secp256k1 private key for signing from a UInt256 constant.

Instance Methods

func add([UInt8]) throws -> P256K.Signing.PrivateKey
Creates a new P256K.Signing.PrivateKey by computing secret_key' = (secret_key + tweak) mod n via secp256k1_ec_seckey_tweak_add (declared in Vendor/secp256k1/include/secp256k1.h), where n is the secp256k1 curve order.
func multiply([UInt8]) throws -> P256K.Signing.PrivateKey
Creates a new P256K.Signing.PrivateKey by computing secret_key' = (secret_key × tweak) mod n via secp256k1_ec_seckey_tweak_mul, where n is the secp256k1 curve order.
func signature<D>(for: D) -> P256K.Signing.ECDSASignature
Generates a lower-S normalized ECDSA signature by first hashing data with SHA-256, then signing with secp256k1_ecdsa_sign.
func signature<D>(for: D) -> P256K.Signing.ECDSASignature
Generates a lower-S normalized ECDSA signature over the secp256k1 elliptic curve using RFC 6979 deterministic nonce generation.