Struct ControlBlock

pub struct ControlBlock {
    pub leaf_version: LeafVersion,
    pub output_key_parity: Parity,
    pub internal_key: XOnlyPublicKey,
    pub merkle_branch: TaprootMerkleBranch,
}

Control block data structure used in Tapscript satisfaction.

Fields

leaf_version: LeafVersion

The tapleaf version.

output_key_parity: Parity

The parity of the output key (NOT THE INTERNAL KEY WHICH IS ALWAYS XONLY).

internal_key: XOnlyPublicKey

The internal key.

merkle_branch: TaprootMerkleBranch

The merkle proof of a script associated with this leaf.

Implementations

impl ControlBlock

pub fn decode(sl: &[u8]) -> Result<ControlBlock, TaprootError>

Decodes bytes representing a ControlBlock.

This is an extra witness element that provides the proof that taproot script pubkey is correctly computed with some specified leaf hash. This is the last element in taproot witness when spending a output via script path.

Errors

• TaprootError::InvalidControlBlockSize if sl is not of size 1 + 32 + 32N for any N >= 0.
• TaprootError::InvalidTaprootLeafVersion if first byte of sl is not a valid leaf version.
• TaprootError::InvalidInternalKey if internal key is invalid (first 32 bytes after the parity byte).
• TaprootError::InvalidMerkleTreeDepth if merkle tree is too deep (more than 128 levels).

pub fn size(&self) -> usize

Returns the size of control block. Faster and more efficient than calling Self::serialize().len(). Can be handy for fee estimation.

pub fn encode<W>(&self, writer: &mut W) -> Result<usize, Error>

where W: Write + ?Sized,

Serializes to a writer.

Returns

The number of bytes written to the writer.

pub fn serialize(&self) -> Vec<u8>

Serializes the control block.

This would be required when using ControlBlock as a witness element while spending an output via script path. This serialization does not include the crate::VarInt prefix that would be applied when encoding this element as a witness.

pub fn verify_taproot_commitment<C>( &self, secp: &Secp256k1<C>, output_key: XOnlyPublicKey, script: &Script, ) -> bool

where C: Verification,

Verifies that a control block is correct proof for a given output key and script.

Only checks that script is contained inside the taptree described by output key. Full verification must also execute the script with witness data.

Trait Implementations

impl Clone for ControlBlock

fn clone(&self) -> ControlBlock

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ControlBlock

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for ControlBlock

fn deserialize<__D>( __deserializer: __D, ) -> Result<ControlBlock, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Hash for ControlBlock

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

where __H: Hasher,

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 Ord for ControlBlock

fn cmp(&self, other: &ControlBlock) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for ControlBlock

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

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

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 PartialOrd for ControlBlock

fn partial_cmp(&self, other: &ControlBlock) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

Tests less than (for self and other) and is used by the < operator.

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

Tests less than or equal to (for self and other) and is used by the <= operator.

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

Tests greater than (for self and other) and is used by the > operator.

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

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for ControlBlock

fn serialize<__S>( &self, __serializer: __S, ) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for ControlBlock

impl StructuralPartialEq for ControlBlock