package lnwire import ( "io" "github.com/roasbeef/btcd/wire" ) // UpdateFufillHTLC is sent by Alice to Bob when she wishes to settle a // particular HTLC referenced by its HTLCKey within a specific active channel // referenced by ChannelPoint. A subsequent CommitSig message will be sent by // Alice to "lock-in" the removal of the specified HTLC, possible containing a // batch signature covering several settled HTLC's. type UpdateFufillHTLC struct { // ChannelPoint references an active channel which holds the HTLC to be // settled. ChannelPoint wire.OutPoint // ID denotes the exact HTLC stage within the receiving node's // commitment transaction to be removed. ID uint64 // PaymentPreimage is the R-value preimage required to fully settle an // HTLC. PaymentPreimage [32]byte } // NewUpdateFufillHTLC returns a new empty UpdateFufillHTLC. func NewUpdateFufillHTLC(chanPoint wire.OutPoint, id uint64, preimage [32]byte) *UpdateFufillHTLC { return &UpdateFufillHTLC{ ChannelPoint: chanPoint, ID: id, PaymentPreimage: preimage, } } // A compile time check to ensure UpdateFufillHTLC implements the lnwire.Message // interface. var _ Message = (*UpdateFufillHTLC)(nil) // Decode deserializes a serialized UpdateFufillHTLC message stored in the passed // io.Reader observing the specified protocol version. // // This is part of the lnwire.Message interface. func (c *UpdateFufillHTLC) Decode(r io.Reader, pver uint32) error { // ChannelPoint(8) // ID(8) // PaymentPreimage(32) return readElements(r, &c.ChannelPoint, &c.ID, c.PaymentPreimage[:], ) } // Encode serializes the target UpdateFufillHTLC into the passed io.Writer // observing the protocol version specified. // // This is part of the lnwire.Message interface. func (c *UpdateFufillHTLC) Encode(w io.Writer, pver uint32) error { return writeElements(w, c.ChannelPoint, c.ID, c.PaymentPreimage[:], ) } // Command returns the integer uniquely identifying this message type on the // wire. // // This is part of the lnwire.Message interface. func (c *UpdateFufillHTLC) Command() uint32 { return CmdUpdateFufillHTLC } // MaxPayloadLength returns the maximum allowed payload size for a UpdateFufillHTLC // complete message observing the specified protocol version. // // This is part of the lnwire.Message interface. func (c *UpdateFufillHTLC) MaxPayloadLength(uint32) uint32 { // 36 + 8 + (32 * 15) return 524 } // Validate performs any necessary sanity checks to ensure all fields present // on the UpdateFufillHTLC are valid. // // This is part of the lnwire.Message interface. func (c *UpdateFufillHTLC) Validate() error { // We're good! return nil }