Trait lnpbp::commit_verify::EmbedCommitVerify

pub trait EmbedCommitVerify<MSG>: Eq {
    type Container: Clone;
    type Error: Error;
    pub fn embed_commit(
        container: &mut Self::Container, 
        msg: &MSG
    ) -> Result<Self, Self::Error>;

    pub fn verify(
        &self, 
        container: &Self::Container, 
        msg: &MSG
    ) -> Result<bool, Self::Error> { ... }
}

Trait for embed-commit-verify scheme, where some data structure (named container) may commit to existing message (producing commitment data structure) in such way that the original message can't be restored from the commitment, however the fact of the commitment may be deterministically checked when the message is revealed against the original container.

To use embed-commit-verify scheme one needs to implement this trait for the commitment data structure and provide it (through associated types) with the used container type.

Operations with embed-commit-verify scheme may be represented in form of EmbedCommit: (Container, Message) -> Commitment and Verify: (Commitment, Container, Message) -> bool; the original container is required for the verification procedure.

This trait is heavily used in deterministic bitcoin commitments [crate::dbc] module implementations

Associated Types

type Container: Clone

External container type that will be used to host commitment to a message

type Error: Error

Error type that may be reported during [commit_embed] procedure

Loading content...

Required methods

pub fn embed_commit(
    container: &mut Self::Container,
    msg: &MSG
) -> Result<Self, Self::Error>

Creates a commitment and embeds it into the provided container returning Self containing both message commitment and all additional data required to reconstruct the original container

Loading content...

Provided methods

pub fn verify(
    &self,
    container: &Self::Container,
    msg: &MSG
) -> Result<bool, Self::Error>

Verifies commitment against the message; default implementation just reconstructs the original container with [container] function, repeats the commitment to the message and check it against the self.

Verification is a failable procedure returning bool. The difference between returning Ok(false) and Err(_) is the following:

• Err(_): validation was not possible due to container data structure- related error or some internal error during the validation process. It is undefined whether the message corresponds to the commitment.
• Ok(false): validation was performed completely; the message does not correspond to the commitment
• Ok(true): validation was performed completely; the message does correspond to the commitment

Loading content...

Implementors

impl<MSG> EmbedCommitVerify<MSG> for KeysetCommitment where
    MSG: AsRef<[u8]>, 

type Container = KeysetContainer

type Error = Error

fn embed_commit(
    keyset_container: &mut Self::Container,
    msg: &MSG
) -> Result<Self, Self::Error>

impl<MSG> EmbedCommitVerify<MSG> for LockscriptCommitment where
    MSG: AsRef<[u8]>, 

type Container = LockscriptContainer

type Error = Error

fn embed_commit(
    container: &mut Self::Container,
    msg: &MSG
) -> Result<Self, Self::Error>

Function implements commitment procedure according to LNPBP-2.

LNPBP-2 Specification extract:

1. The provided script MUST be parsed with Miniscript parser; if the parser fails the procedure MUST fail.
2. Iterate over all branches of the abstract syntax tree generated by the Miniscript parser, running the following algorithm for each node:
   • if a public key hash is met (pk_h Miniscript command) and it can't be resolved against known public keys or other public keys extracted from the script, fail the procedure;
   • if a public key is found (pk) add it to the list of the collected public keys;
   • for all other types of Miniscript commands iterate over their branches.
3. Select unique public keys (i.e. if some public key is repeated in different parts of the script/in different script branches, pick a single instance of it). Compressed and uncompressed versions of the same public key must be treaded as the same public key under this procedure.
4. If no public keys were found fail the procedure; return the collected keys otherwise.

NB: SUBJECT TO CHANGE UPON RELEASE By "miniscript" we mean usage of rust-miniscript library at commit a5ba1219feb8b5a289c8f12176d632635eb8a959 which may be found on https://github.com/LNP-BP/rust-miniscript/commit/a5ba1219feb8b5a289c8f12176d632635eb8a959

impl<MSG> EmbedCommitVerify<MSG> for PubkeyCommitment where
    MSG: AsRef<[u8]>, 

type Container = PubkeyContainer

type Error = Error

fn embed_commit(
    pubkey_container: &mut Self::Container,
    msg: &MSG
) -> Result<Self, Self::Error>

impl<MSG> EmbedCommitVerify<MSG> for SpkCommitment where
    MSG: AsRef<[u8]>, 

type Container = SpkContainer

type Error = Error

fn embed_commit(
    container: &mut Self::Container,
    msg: &MSG
) -> Result<Self, Self::Error>

impl<MSG> EmbedCommitVerify<MSG> for TaprootCommitment where
    MSG: AsRef<[u8]>, 

type Container = TaprootContainer

type Error = Error

fn embed_commit(
    container: &mut Self::Container,
    msg: &MSG
) -> Result<Self, Self::Error>

impl<MSG> EmbedCommitVerify<MSG> for TxCommitment where
    MSG: AsRef<[u8]>, 

type Container = TxContainer

type Error = Error

fn embed_commit(
    container: &mut Self::Container,
    msg: &MSG
) -> Result<Self, Self::Error>

impl<MSG> EmbedCommitVerify<MSG> for TxoutCommitment where
    MSG: AsRef<[u8]>, 

type Container = TxoutContainer

type Error = Error

fn embed_commit(
    container: &mut Self::Container,
    msg: &MSG
) -> Result<Self, Self::Error>

Loading content...