Trait bp_messages::target_chain::SourceHeaderChain

pub trait SourceHeaderChain {
    type MessagesProof: Parameter + Size;

    // Required method
    fn verify_messages_proof(
        proof: Self::MessagesProof,
        messages_count: u32,
    ) -> Result<ProvedMessages<Message>, VerificationError>;
}

Source chain API. Used by target chain, to verify source chain proofs.

All implementations of this trait should only work with finalized data that can’t change. Wrong implementation may lead to invalid lane states (i.e. lane that’s stuck) and/or processing messages without paying fees.

Required Associated Types

type MessagesProof: Parameter + Size

Proof that messages are sent from source chain. This may also include proof of corresponding outbound lane states.

Required Methods

fn verify_messages_proof( proof: Self::MessagesProof, messages_count: u32, ) -> Result<ProvedMessages<Message>, VerificationError>

Verify messages proof and return proved messages.

Returns error if either proof is incorrect, or the number of messages in the proof is not matching the messages_count.

Messages vector is required to be sorted by nonce within each lane. Out-of-order messages will be rejected.

The messages_count argument verification (sane limits) is supposed to be made outside this function. This function only verifies that the proof declares exactly messages_count messages.

Object Safety

This trait is not object safe.

Implementors

impl<MessagesProof: Parameter + Size, DispatchPayload> SourceHeaderChain for ForbidInboundMessages<MessagesProof, DispatchPayload>

type MessagesProof = MessagesProof