EthereumSchorrSigner

Ethereum ERC-7816 compatible Schnorr signer.

For implementation details please go to the specification

Properties

struct {
  /// The private key of this signer.
  private_key: CompressedScalar
  /// The compressed version of the address of this signer.
  public_key: CompressedPublicKey
  /// The chain address of this signer.
  address_bytes: Address
}

SigningErrors

Set of possible errors when signing a message.

NotSquareError || NonCanonicalError || EncodingError ||
        IdentityElementError || error{ InvalidNonce, InvalidPrivateKey }

Init

Creates the signer state.

Generates a compressed public key from the provided private_key.

If a null value is provided a random key will be generated. This is to mimic the behaviour from zig's KeyPair types.

Signature

pub fn init(private_key: ?CompressedScalar) IdentityElementError!Self

ConstructMessageHash

Constructs the message digest based on the previously signed message.

Signature

pub fn constructMessageHash(message: CompressedScalar) CompressedScalar

HashNonce

Generates the k value from random bytes and the private_key.

Signature

pub fn hashNonce(random_buffer: CompressedScalar, priv_key: CompressedScalar) CompressedScalar

HashChallenge

Generates the Schnorr challenge from R bytes, a message_construct and a generated ethereum address.

Signature

pub fn hashChallenge(
    public_key: CompressedPublicKey,
    message_digest: CompressedScalar,
    address: Address,
) (EncodingError || NonCanonicalError || NotSquareError)!CompressedScalar

GenerateAddress

Generates an ethereum address from the x coordinates from a public key.

Signature

pub fn generateAddress(r: CompressedScalar) Address

PrivateKeyToScalar

Converts the private_key to a Secp256k1 scalar.

Negates the scalar if the y coordinates are odd.

Signature

pub fn privateKeyToScalar(self: Self) (NonCanonicalError || NotSquareError || EncodingError || error{InvalidPrivateKey})!Scalar

SignUnsafe

Generates a Schnorr signature for a given message.

This will not verify if the generated signature is correct. Please use verifyMessage to make sure that the generated signature is valid.

Signature

pub fn signUnsafe(self: Self, message: CompressedScalar) SigningErrors!EthereumSchnorrSignature

Sign

Generates a Schnorr signature for a given message.

This verifies if the generated signature is valid. Otherwise an InvalidSignature error is returned.

Signature

pub fn sign(self: Self, message: CompressedScalar) (SigningErrors || error{InvalidSignature})!EthereumSchnorrSignature

VerifySignature

Verifies if the provided signature was signed by Self.

Signature

pub fn verifySignature(self: Self, message: CompressedScalar, signature: EthereumSchnorrSignature) bool

VerifyMessage

Verifies if the provided signature was signed by the provided x coordinate bytes from a compressed public key.

Signature

pub fn verifyMessage(public_key: CompressedPublicKey, message_construct: CompressedScalar, signature: EthereumSchnorrSignature) bool

SigningErrors

Set of possible errors when signing a message.

NotSquareError || NonCanonicalError || EncodingError ||
        IdentityElementError || error{ InvalidNonce, InvalidPrivateKey }

SchnorrSigner

BIP0340 Schnorr signer.

For implementation details please go to the specification

Properties

struct {
  /// The private key of this signer.
  private_key: CompressedScalar
  /// The compressed version of the address of this signer.
  public_key: CompressedPublicKey
}

SigningErrors

Set of possible errors when signing a message.

NotSquareError || NonCanonicalError || EncodingError ||
        IdentityElementError || error{ InvalidNonce, InvalidPrivateKey }

Init

Generates a compressed public key from the provided private_key.

If a null value is provided a random key will be generated. This is to mimic the behaviour from zig's KeyPair types.

Signature

pub fn init(private_key: ?CompressedScalar) IdentityElementError!Self

PrivateKeyToScalar

Converts the private_key to a Secp256k1 scalar.

Negates the scalar if the y coordinates are odd.

Signature

pub fn privateKeyToScalar(self: Self) (NonCanonicalError || NotSquareError || EncodingError || error{InvalidPrivateKey})!Scalar

SignUnsafe

Generates a Schnorr signature for a given message.

This will not verify if the generated signature is correct. Please use verifyMessage to make sure that the generated signature is valid.

Signature

pub fn signUnsafe(self: Self, message: []const u8) SigningErrors!SchnorrSignature

Sign

Generates a Schnorr signature for a given message.

This verifies if the generated signature is valid. Otherwise an InvalidSignature error is returned.

Signature

pub fn sign(self: Self, message: []const u8) (SigningErrors || error{InvalidSignature})!SchnorrSignature

VerifySignature

Verifies if the provided signature was signed by Self.

Signature

pub fn verifySignature(self: Self, signature: SchnorrSignature, message: []const u8) bool

VerifyMessage

Verifies if the provided signature was signed by the provided x coordinate bytes from a compressed public key.

Signature

pub fn verifyMessage(pub_key: CompressedScalar, signature: SchnorrSignature, message: []const u8) bool

HashAux

Generates the auxiliary hash from a random set of bytes.

Signature

pub fn hashAux(random_buffer: [32]u8) CompressedScalar

HashNonce

Generates the k value from the mask of the aux hash and a public_key with the message.

Signature

pub fn hashNonce(t: [32]u8, public_key: [32]u8, message: []const u8) CompressedScalar

HashChallenge

Generates the Schnorr challenge from R bytes, public_key and the message to sign.

Signature

pub fn hashChallenge(k_r: [32]u8, pub_key: [32]u8, message: []const u8) CompressedScalar

SigningErrors

Set of possible errors when signing a message.

NotSquareError || NonCanonicalError || EncodingError ||
        IdentityElementError || error{ InvalidNonce, InvalidPrivateKey }

GenerateR

Generates a public key with a private key Scalar based on a random generated nonce.

Signature

pub fn generateR(bytes: CompressedScalar) (NonCanonicalError || IdentityElementError || error{InvalidNonce})!PublicKeyAndScalar

LiftX

Extracts a point from the Secp256k1 curve based on the provided x coordinates from a CompressedPublicKey array of bytes.

Signature

pub fn liftX(encoded: CompressedScalar) (NonCanonicalError || NotSquareError)!Secp256k1

NonceToScalar

Generates the k scalar and bytes from a given public_key with the identifier.

Signature

pub fn nonceToScalar(bytes: CompressedScalar) (NonCanonicalError || IdentityElementError || error{InvalidNonce})!RBytesAndScalar