Enum SigningPublicKey

pub enum SigningPublicKey {
    Schnorr(SchnorrPublicKey),
    ECDSA(ECPublicKey),
    Ed25519(Ed25519PublicKey),
    SSH(PublicKey),
    MLDSA(MLDSAPublicKey),
}

A public key used for verifying digital signatures.

SigningPublicKey is an enum representing different types of signing public keys, including elliptic curve schemes (ECDSA, Schnorr), Edwards curve schemes (Ed25519), post-quantum schemes (ML-DSA), and SSH keys.

This type implements the Verifier trait, allowing it to verify signatures of the appropriate type.

Examples

Creating and using a signing public key pair:

use bc_components::{SignatureScheme, Signer, Verifier};

// Create a key pair
let (private_key, public_key) = SignatureScheme::Schnorr.keypair();

// Sign a message
let message = b"Hello, world!";
let signature = private_key.sign(&message).unwrap();

// Verify the signature
assert!(public_key.verify(&signature, &message));

CBOR Serialization

SigningPublicKey can be serialized to and from CBOR with appropriate tags:

use bc_components::{SignatureScheme, SigningPublicKey};
use dcbor::prelude::*;

// Create a key pair and get the public key
let (_, public_key) = SignatureScheme::Schnorr.keypair();

// Convert to CBOR
let cbor: CBOR = public_key.clone().into();
let data = cbor.to_cbor_data();

// Convert back from CBOR
let recovered = SigningPublicKey::from_tagged_cbor_data(&data).unwrap();

// The keys should be equal
assert_eq!(public_key, recovered);

Variants

Schnorr(SchnorrPublicKey)

A Schnorr public key (BIP-340, x-only)

ECDSA(ECPublicKey)

An ECDSA public key (compressed, 33 bytes)

Ed25519(Ed25519PublicKey)

An Ed25519 public key

SSH(PublicKey)

An SSH public key

MLDSA(MLDSAPublicKey)

A post-quantum ML-DSA public key

Implementations

impl SigningPublicKey

pub fn from_schnorr(key: SchnorrPublicKey) -> Self

Creates a new signing public key from a Schnorr public key.

Arguments

• key - A BIP-340 Schnorr public key

Returns

A new signing public key containing the Schnorr key

Examples

use bc_components::{SchnorrPublicKey, SigningPublicKey};

// Create a Schnorr public key
let schnorr_key = SchnorrPublicKey::from_data([0u8; 32]);

// Create a signing public key from it
let signing_key = SigningPublicKey::from_schnorr(schnorr_key);

pub fn from_ecdsa(key: ECPublicKey) -> Self

Creates a new signing public key from an ECDSA public key.

Arguments

• key - A compressed ECDSA public key

Returns

A new signing public key containing the ECDSA key

Examples

use bc_components::{ECKey, ECPrivateKey, SigningPublicKey};

// Create an EC private key and derive its public key
let private_key = ECPrivateKey::new();
let public_key = private_key.public_key();

// Create a signing public key from it
let signing_key = SigningPublicKey::from_ecdsa(public_key);

pub fn from_ed25519(key: Ed25519PublicKey) -> Self

Creates a new signing public key from an Ed25519 public key.

Arguments

• key - An Ed25519 public key

Returns

A new signing public key containing the Ed25519 key

Examples

use bc_components::{Ed25519PrivateKey, SigningPublicKey};

// Create an Ed25519 private key and get its public key
let private_key = Ed25519PrivateKey::new();
let public_key = private_key.public_key();

// Create a signing public key from it
let signing_key = SigningPublicKey::from_ed25519(public_key);

pub fn from_ssh(key: SSHPublicKey) -> Self

Creates a new signing public key from an SSH public key.

Arguments

• key - An SSH public key

Returns

A new signing public key containing the SSH key

pub fn to_schnorr(&self) -> Option<&SchnorrPublicKey>

Returns the underlying Schnorr public key if this is a Schnorr key.

Returns

Some reference to the Schnorr public key if this is a Schnorr key, or None if it’s a different key type.

Examples

use bc_components::{SignatureScheme, Signer};

// Create a Schnorr key pair
let (private_key, public_key) = SignatureScheme::Schnorr.keypair();

// We can access the Schnorr public key
assert!(public_key.to_schnorr().is_some());

// Create an ECDSA key pair
let (_, ecdsa_public) = SignatureScheme::Ecdsa.keypair();

// This will return None since it's not a Schnorr key
assert!(ecdsa_public.to_schnorr().is_none());

pub fn to_ecdsa(&self) -> Option<&ECPublicKey>

Returns the underlying ECDSA public key if this is an ECDSA key.

Returns

Some reference to the ECDSA public key if this is an ECDSA key, or None if it’s a different key type.

pub fn to_ssh(&self) -> Option<&SSHPublicKey>

Returns the underlying SSH public key if this is an SSH key.

Returns

Some reference to the SSH public key if this is an SSH key, or None if it’s a different key type.

Trait Implementations

impl AsRef<SigningPublicKey> for PublicKeys

fn as_ref(&self) -> &SigningPublicKey

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<SigningPublicKey> for SigningPublicKey

Implementation of AsRef for SigningPublicKey

fn as_ref(&self) -> &SigningPublicKey

Returns a reference to self.

impl CBORTagged for SigningPublicKey

Implementation of the CBORTagged trait for SigningPublicKey

fn cbor_tags() -> Vec<Tag>

Returns the CBOR tags used for this type.

For SigningPublicKey, the tag is 40022.

impl CBORTaggedDecodable for SigningPublicKey

Implementation of the CBORTaggedDecodable trait for SigningPublicKey

fn from_untagged_cbor(untagged_cbor: CBOR) -> Result<Self>

Creates a SigningPublicKey from an untagged CBOR value.

Arguments

• untagged_cbor - The CBOR value to decode

Returns

A Result containing the decoded SigningPublicKey or an error if decoding fails.

Format

The CBOR value must be one of:

• A byte string (interpreted as a Schnorr public key)
• An array of length 2, where the first element is a discriminator (1 for ECDSA, 2 for Ed25519) and the second element is a byte string containing the key data
• A tagged value with a tag for ML-DSA or SSH keys

fn from_tagged_cbor(cbor: CBOR) -> Result<Self, Error>

where Self: Sized,

Creates an instance of this type by decoding it from tagged CBOR.

fn from_tagged_cbor_data(data: impl AsRef<[u8]>) -> Result<Self, Error>

where Self: Sized,

Creates an instance of this type by decoding it from binary encoded tagged CBOR.

fn from_untagged_cbor_data(data: impl AsRef<[u8]>) -> Result<Self, Error>

where Self: Sized,

Creates an instance of this type by decoding it from binary encoded untagged CBOR.

impl CBORTaggedEncodable for SigningPublicKey

Implementation of the CBORTaggedEncodable trait for SigningPublicKey

fn untagged_cbor(&self) -> CBOR

Converts the SigningPublicKey to an untagged CBOR value.

The CBOR encoding depends on the key type:

• Schnorr: A byte string containing the 32-byte x-only public key
• ECDSA: An array containing the discriminator 1 and the 33-byte compressed public key
• Ed25519: An array containing the discriminator 2 and the 32-byte public key
• SSH: A tagged text string containing the OpenSSH-encoded public key
• ML-DSA: Delegates to the MLDSAPublicKey implementation

fn tagged_cbor(&self) -> CBOR

Returns the tagged CBOR encoding of this instance.

fn tagged_cbor_data(&self) -> Vec<u8>

Returns the tagged value in CBOR binary representation.

impl Clone for SigningPublicKey

fn clone(&self) -> SigningPublicKey

Returns a duplicate of the value.

const fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SigningPublicKey

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<&SigningPublicKey> for XID

Implements conversion from SigningPublicKey reference to XID.

fn from(key: &SigningPublicKey) -> Self

Converts to this type from the input type.

impl From<SigningPublicKey> for CBOR

Conversion from SigningPublicKey to CBOR

fn from(value: SigningPublicKey) -> Self

Converts a SigningPublicKey to a tagged CBOR value.

impl Hash for SigningPublicKey

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for SigningPublicKey

fn eq(&self, other: &SigningPublicKey) -> bool

Tests for self and other values to be equal, and is used by ==.

const fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl TryFrom<CBOR> for SigningPublicKey

TryFrom implementation for converting CBOR to SigningPublicKey

fn try_from(cbor: CBOR) -> Result<Self>

Tries to convert a CBOR value to a SigningPublicKey.

This is a convenience method that calls from_tagged_cbor.

type Error = Error

The type returned in the event of a conversion error.

impl Verifier for SigningPublicKey

Implementation of the Verifier trait for SigningPublicKey

fn verify(&self, signature: &Signature, message: &dyn AsRef<[u8]>) -> bool

Verifies a signature against a message.

The type of signature must match the type of this key, and the signature must be valid for the message, or the verification will fail.

Arguments

• signature - The signature to verify
• message - The message that was allegedly signed

Returns

true if the signature is valid for the message, false otherwise

Examples

use bc_components::{SignatureScheme, Signer, Verifier};

// Create a key pair
let (private_key, public_key) = SignatureScheme::Schnorr.keypair();

// Sign a message
let message = b"Hello, world!";
let signature = private_key.sign(&message).unwrap();

// Verify the signature with the correct message (should succeed)
assert!(public_key.verify(&signature, &message));

// Verify the signature with an incorrect message (should fail)
assert!(!public_key.verify(&signature, &b"Tampered message"));

impl XIDProvider for SigningPublicKey

Implements XIDProvider for SigningPublicKey to generate an XID from the key.

fn xid(&self) -> XID

Returns the XID for this object.

impl Eq for SigningPublicKey

impl StructuralPartialEq for SigningPublicKey