lnd.xprv/lnwire/htlc_settlerequest.go
Olaoluwa Osuntokun 6c7880ef76
lnwire: channels are now identified by outpoint
This commit modifies most of the wire messages to uniquely identify any
*active* channels by their funding output. This allows the wire
protocol to support funding transactions which open several channels in
parallel.

Any pending channels created by partial completion of the funding
workflow are to be identified by a uint64 initialized by both sides as
follows: the initiator of the connection starts from 0, while the
listening node starts from (1 << 63). These pending channel identifiers
are expected to be monotonically increasing with each new funding
workflow between two nodes. This identifier is volatile w.r.t to each
connection initiation.
2016-06-21 13:13:07 -07:00

127 lines
3.6 KiB
Go

package lnwire
import (
"fmt"
"io"
"github.com/roasbeef/btcd/wire"
)
// HTLCSettleRequest 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. The message allows multiple hash preimages to be
// presented in order to support N-of-M HTLC contracts. A subsequent
// CommitSignature 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 HTLCSettleRequest struct {
// ChannelPoint references an active channel which holds the HTLC to be
// settled.
ChannelPoint *wire.OutPoint
// HTLCKey denotes the exact HTLC stage within the receiving node's
// commitment transaction to be removed.
HTLCKey HTLCKey
// RedemptionProofs are the R-value preimages required to fully settle
// an HTLC. The number of preimages in the slice will depend on the
// specific ContractType of the referenced HTLC.
RedemptionProofs [][20]byte
}
// NewHTLCSettleRequest returns a new empty HTLCSettleRequest.
func NewHTLCSettleRequest(chanPoint *wire.OutPoint, key HTLCKey,
redemptionProofs [][20]byte) *HTLCSettleRequest {
return &HTLCSettleRequest{
ChannelPoint: chanPoint,
HTLCKey: key,
RedemptionProofs: redemptionProofs,
}
}
// A compile time check to ensure HTLCSettleRequest implements the lnwire.Message
// interface.
var _ Message = (*HTLCSettleRequest)(nil)
// Decode deserializes a serialized HTLCSettleRequest message stored in the passed
// io.Reader observing the specified protocol version.
//
// This is part of the lnwire.Message interface.
func (c *HTLCSettleRequest) Decode(r io.Reader, pver uint32) error {
// ChannelPoint(8)
// HTLCKey(8)
// RedemptionProofs(N*20)
err := readElements(r,
&c.ChannelPoint,
&c.HTLCKey,
&c.RedemptionProofs,
)
if err != nil {
return err
}
return nil
}
// Encode serializes the target HTLCSettleRequest into the passed io.Writer
// observing the protocol version specified.
//
// This is part of the lnwire.Message interface.
func (c *HTLCSettleRequest) Encode(w io.Writer, pver uint32) error {
err := writeElements(w,
c.ChannelPoint,
c.HTLCKey,
c.RedemptionProofs,
)
if err != nil {
return err
}
return nil
}
// Command returns the integer uniquely identifying this message type on the
// wire.
//
// This is part of the lnwire.Message interface.
func (c *HTLCSettleRequest) Command() uint32 {
return CmdHTLCSettleRequest
}
// MaxPayloadLength returns the maximum allowed payload size for a HTLCSettleRequest
// complete message observing the specified protocol version.
//
// This is part of the lnwire.Message interface.
func (c *HTLCSettleRequest) MaxPayloadLength(uint32) uint32 {
// 36 + 8 + (21 * 15)
return 359
}
// Validate performs any necessary sanity checks to ensure all fields present
// on the HTLCSettleRequest are valid.
//
// This is part of the lnwire.Message interface.
func (c *HTLCSettleRequest) Validate() error {
// We're good!
return nil
}
// String returns the string representation of the target HTLCSettleRequest.
//
// This is part of the lnwire.Message interface.
func (c *HTLCSettleRequest) String() string {
var redemptionProofs string
for i, rh := range c.RedemptionProofs {
redemptionProofs += fmt.Sprintf("\n\tSlice\t%d\n", i)
redemptionProofs += fmt.Sprintf("\t\tRedemption Proof: %x\n", rh)
}
return fmt.Sprintf("\n--- Begin HTLCSettleRequest ---\n") +
fmt.Sprintf("ChannelPoint:\t%d\n", c.ChannelPoint) +
fmt.Sprintf("HTLCKey:\t%d\n", c.HTLCKey) +
fmt.Sprintf("RedemptionHashes:") +
redemptionProofs +
fmt.Sprintf("--- End HTLCSettleRequest ---\n")
}