Struct UNSPENDABLE_XONLY_PUBKEY

pub struct UNSPENDABLE_XONLY_PUBKEY { /* private fields */ }

This is an unspendable pubkey.

See https://github.com/bitcoin/bips/blob/master/bip-0341.mediawiki#constructing-and-spending-taproot-outputs

It is used to create a taproot address where the internal key is not spendable. Here are the other protocols that use this key:

• Babylon:https://github.com/babylonlabs-io/btc-staking-ts/blob/v0.4.0-rc.2/src/constants/internalPubkey.ts
• Ark: https://github.com/ark-network/ark/blob/cba48925bcc836cc55f9bb482f2cd1b76d78953e/common/tree/validation.go#L47
• BitVM: https://github.com/BitVM/BitVM/blob/2dd2e0e799d2b9236dd894da3fee8c4c4893dcf1/bridge/src/scripts.rs#L16
• Best in Slot: https://github.com/bestinslot-xyz/brc20-programmable-module/blob/2113bdd73430a8c3757e537cb63124a6cb33dfab/src/evm/precompiles/get_locked_pkscript_precompile.rs#L53
• https://github.com/BlockstreamResearch/options/blob/36a77175919101393b49f1211732db762cc7dfc1/src/options_lib/src/contract.rs#L132

Methods from Deref<Target = XOnlyPublicKey>

pub fn cmp_fast_unstable(&self, other: &XOnlyPublicKey) -> Ordering

Like cmp::Cmp but faster and with no guarantees across library versions.

The Cmp implementation for FFI types is stable but slow because it first serializes self and other before comparing them. This function provides a faster comparison if you know that your types come from the same library version.

pub fn eq_fast_unstable(&self, other: &XOnlyPublicKey) -> bool

Like cmp::Eq but faster and with no guarantees across library versions.

The Eq implementation for FFI types is stable but slow because it first serializes self and other before comparing them. This function provides a faster equality check if you know that your types come from the same library version.

pub fn as_ptr(&self) -> *const XOnlyPublicKey

👎Deprecated since 0.25.0: Use Self::as_c_ptr if you need to access the FFI layer

Obtains a raw const pointer suitable for use with FFI functions.

pub fn serialize(&self) -> [u8; 32]

Serializes the key as a byte-encoded x coordinate value (32 bytes).

pub fn tweak_add_check<V>( &self, secp: &Secp256k1<V>, tweaked_key: &XOnlyPublicKey, tweaked_parity: Parity, tweak: Scalar, ) -> bool

where V: Verification,

Verifies that a tweak produced by [XOnlyPublicKey::add_tweak] was computed correctly.

Should be called on the original untweaked key. Takes the tweaked key and output parity from [XOnlyPublicKey::add_tweak] as input.

Currently this is not much more efficient than just recomputing the tweak and checking equality. However, in future this API will support batch verification, which is significantly faster, so it is wise to design protocols with this in mind.

Returns

True if tweak and check is successful, false otherwise.

Examples

use secp256k1::{Secp256k1, Keypair, Scalar};

let secp = Secp256k1::new();
let tweak = Scalar::random();

let mut keypair = Keypair::new(&secp, &mut rand::thread_rng());
let (mut public_key, _) = keypair.x_only_public_key();
let original = public_key;
let (tweaked, parity) = public_key.add_tweak(&secp, &tweak).expect("Improbable to fail with a randomly generated tweak");
assert!(original.tweak_add_check(&secp, &tweaked, parity, tweak));

pub fn public_key(&self, parity: Parity) -> PublicKey

Returns the [PublicKey] for this [XOnlyPublicKey].

This is equivalent to using [PublicKey::from_xonly_and_parity(self, parity)].

pub fn verify<C>( &self, secp: &Secp256k1<C>, msg: &Message, sig: &Signature, ) -> Result<(), Error>

where C: Verification,

Checks that sig is a valid schnorr signature for msg using this public key.

Trait Implementations

impl Deref for UNSPENDABLE_XONLY_PUBKEY

type Target = XOnlyPublicKey

The resulting type after dereferencing.

fn deref(&self) -> &XOnlyPublicKey

Dereferences the value.

impl LazyStatic for UNSPENDABLE_XONLY_PUBKEY