package lnwire import ( "io" "github.com/roasbeef/btcd/btcec" ) // CommitSig is sent by either side to stage any pending HTLC's in the // receiver's pending set into a new commitment state. Implicitly, the new // commitment transaction constructed which has been signed by CommitSig // includes all HTLC's in the remote node's pending set. A CommitSig message // may be sent after a series of UpdateAddHTLC/UpdateFufillHTLC messages in // order to batch add several HTLC's with a single signature covering all // implicitly accepted HTLC's. type CommitSig struct { // ChanID uniquely identifies to which currently active channel this // CommitSig applies to. ChanID ChannelID // CommitSig is Alice's signature for Bob's new commitment transaction. // Alice is able to send this signature without requesting any // additional data due to the piggybacking of Bob's next revocation // hash in his prior RevokeAndAck message, as well as the canonical // ordering used for all inputs/outputs within commitment transactions. // If initiating a new commitment state, this signature should ONLY // cover all of the sending party's pending log updates, and the log // updates of the remote party that have been ACK'd. CommitSig *btcec.Signature // HtlcSigs is a signature for each relevant HTLC output within the // created commitment. The order of the signatures is expected to be // identical to the placement of the HTLC's within the BIP 69 sorted // commitment transaction. For each outgoing HTLC (from the PoV of the // sender of this message), a signature for a HTLC timeout transaction // should be signed, for each incoming HTLC the HTLC timeout // transaction should be signed. HtlcSigs []*btcec.Signature } // NewCommitSig creates a new empty CommitSig message. func NewCommitSig() *CommitSig { return &CommitSig{} } // A compile time check to ensure CommitSig implements the lnwire.Message // interface. var _ Message = (*CommitSig)(nil) // Decode deserializes a serialized CommitSig message stored in the // passed io.Reader observing the specified protocol version. // // This is part of the lnwire.Message interface. func (c *CommitSig) Decode(r io.Reader, pver uint32) error { return readElements(r, &c.ChanID, &c.CommitSig, &c.HtlcSigs, ) } // Encode serializes the target CommitSig into the passed io.Writer // observing the protocol version specified. // // This is part of the lnwire.Message interface. func (c *CommitSig) Encode(w io.Writer, pver uint32) error { return writeElements(w, c.ChanID, c.CommitSig, c.HtlcSigs, ) } // MsgType returns the integer uniquely identifying this message type on the // wire. // // This is part of the lnwire.Message interface. func (c *CommitSig) MsgType() MessageType { return MsgCommitSig } // MaxPayloadLength returns the maximum allowed payload size for a // CommitSig complete message observing the specified protocol version. // // This is part of the lnwire.Message interface. func (c *CommitSig) MaxPayloadLength(uint32) uint32 { // 32 + 64 + 2 + max_allowed_htlcs return MaxMessagePayload }