package lnwire import ( "io" "github.com/roasbeef/btcd/btcec" "github.com/roasbeef/btcutil" ) // AcceptChannel is the message Bob sends to Alice after she initiates the // single funder channel workflow via a AcceptChannel message. Once Alice // receives Bob's response, then she has all the items necessary to construct // the funding transaction, and both commitment transactions. type AcceptChannel struct { // PendingChannelID serves to uniquely identify the future channel // created by the initiated single funder workflow. PendingChannelID [32]byte // DustLimit is the specific dust limit the sender of this message // would like enforced on their version of the commitment transaction. // Any output below this value will be "trimmed" from the commitment // transaction, with the amount of the HTLC going to dust. DustLimit btcutil.Amount // MaxValueInFlight represents the maximum amount of coins that can be // pending within the channel at any given time. If the amount of funds // in limbo exceeds this amount, then the channel will be failed. MaxValueInFlight MilliSatoshi // ChannelReserve is the amount of BTC that the receiving party MUST // maintain a balance above at all times. This is a safety mechanism to // ensure that both sides always have skin in the game during the // channel's lifetime. ChannelReserve btcutil.Amount // HtlcMinimum is the smallest HTLC that the sender of this message // will accept. HtlcMinimum MilliSatoshi // MinAcceptDepth is the minimum depth that the initiator of the // channel should wait before considering the channel open. MinAcceptDepth uint32 // CsvDelay is the number of blocks to use for the relative time lock // in the pay-to-self output of both commitment transactions. CsvDelay uint16 // MaxAcceptedHTLCs is the total number of incoming HTLC's that the // sender of this channel will accept. // // TODO(roasbeef): acks the initiator's, same with max in flight? MaxAcceptedHTLCs uint16 // FundingKey is the key that should be used on behalf of the sender // within the 2-of-2 multi-sig output that it contained within the // funding transaction. FundingKey *btcec.PublicKey // RevocationPoint is the base revocation point for the sending party. // Any commitment transaction belonging to the receiver of this message // should use this key and their per-commitment point to derive the // revocation key for the commitment transaction. RevocationPoint *btcec.PublicKey // PaymentPoint is the base payment point for the sending party. This // key should be combined with the per commitment point for a // particular commitment state in order to create the key that should // be used in any output that pays directly to the sending party, and // also within the HTLC covenant transactions. PaymentPoint *btcec.PublicKey // DelayedPaymentPoint is the delay point for the sending party. This // key should be combined with the per commitment point to derive the // keys that are used in outputs of the sender's commitment transaction // where they claim funds. DelayedPaymentPoint *btcec.PublicKey // FirstCommitmentPoint is the first commitment point for the sending // party. This value should be combined with the receiver's revocation // base point in order to derive the revocation keys that are placed // within the commitment transaction of the sender. FirstCommitmentPoint *btcec.PublicKey } // A compile time check to ensure AcceptChannel implements the lnwire.Message // interface. var _ Message = (*AcceptChannel)(nil) // Encode serializes the target AcceptChannel into the passed io.Writer // implementation. Serialization will observe the rules defined by the passed // protocol version. // // This is part of the lnwire.Message interface. func (a *AcceptChannel) Encode(w io.Writer, pver uint32) error { return writeElements(w, a.PendingChannelID[:], a.DustLimit, a.MaxValueInFlight, a.ChannelReserve, a.HtlcMinimum, a.MinAcceptDepth, a.CsvDelay, a.MaxAcceptedHTLCs, a.FundingKey, a.RevocationPoint, a.PaymentPoint, a.DelayedPaymentPoint, a.FirstCommitmentPoint, ) } // Decode deserializes the serialized AcceptChannel stored in the passed // io.Reader into the target AcceptChannel using the deserialization rules // defined by the passed protocol version. // // This is part of the lnwire.Message interface. func (a *AcceptChannel) Decode(r io.Reader, pver uint32) error { return readElements(r, a.PendingChannelID[:], &a.DustLimit, &a.MaxValueInFlight, &a.ChannelReserve, &a.HtlcMinimum, &a.MinAcceptDepth, &a.CsvDelay, &a.MaxAcceptedHTLCs, &a.FundingKey, &a.RevocationPoint, &a.PaymentPoint, &a.DelayedPaymentPoint, &a.FirstCommitmentPoint, ) } // MsgType returns the MessageType code which uniquely identifies this message // as a AcceptChannel on the wire. // // This is part of the lnwire.Message interface. func (a *AcceptChannel) MsgType() MessageType { return MsgAcceptChannel } // MaxPayloadLength returns the maximum allowed payload length for a // AcceptChannel message. // // This is part of the lnwire.Message interface. func (a *AcceptChannel) MaxPayloadLength(uint32) uint32 { // 32 + (8 * 4) + (4 * 1) + (2 * 2) + (33 * 5) return 237 }