lnd.xprv/watchtower/wtwire/state_update_reply.go

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package wtwire
import "io"
// StateUpdateCode is an error code returned by a watchtower in response to a
// StateUpdate message.
type StateUpdateCode = ErrorCode
const (
// StateUpdateCodeClientBehind signals that the client's sequence number
// is behind what the watchtower expects based on its LastApplied. This
// error should cause the client to record the LastApplied field in the
// response, and initiate another attempt with the proper sequence
// number.
//
// NOTE: Repeated occurrences of this could be interpreted as an attempt
// to siphon state updates from the client. If the client believes it
// is not violating the protocol, this could be grounds to blacklist
// this tower from future session negotiation.
StateUpdateCodeClientBehind StateUpdateCode = 70
// StateUpdateCodeMaxUpdatesExceeded signals that the client tried to
// send a sequence number beyond the negotiated MaxUpdates of the
// session.
StateUpdateCodeMaxUpdatesExceeded StateUpdateCode = 71
// StateUpdateCodeSeqNumOutOfOrder signals the client sent an update
// that does not follow the required incremental monotonicity required
// by the tower.
StateUpdateCodeSeqNumOutOfOrder StateUpdateCode = 72
)
// StateUpdateReply is a message sent from watchtower to client in response to a
// StateUpdate message, and signals either an acceptance or rejection of the
// proposed state update.
type StateUpdateReply struct {
// Code will be non-zero if the watchtower rejected the state update.
Code StateUpdateCode
// LastApplied returns the sequence number of the last accepted update
// known to the watchtower. If the update was successful, this value
// should be the sequence number of the last update sent.
LastApplied uint16
}
// A compile time check to ensure StateUpdateReply implements the wtwire.Message
// interface.
var _ Message = (*StateUpdateReply)(nil)
// Decode deserializes a serialized StateUpdateReply message stored in the passed
// io.Reader observing the specified protocol version.
//
// This is part of the wtwire.Message interface.
func (t *StateUpdateReply) Decode(r io.Reader, pver uint32) error {
return ReadElements(r,
&t.Code,
&t.LastApplied,
)
}
// Encode serializes the target StateUpdateReply into the passed io.Writer
// observing the protocol version specified.
//
// This is part of the wtwire.Message interface.
func (t *StateUpdateReply) Encode(w io.Writer, pver uint32) error {
return WriteElements(w,
t.Code,
t.LastApplied,
)
}
// MsgType returns the integer uniquely identifying this message type on the
// wire.
//
// This is part of the wtwire.Message interface.
func (t *StateUpdateReply) MsgType() MessageType {
return MsgStateUpdateReply
}
// MaxPayloadLength returns the maximum allowed payload size for a
// StateUpdateReply complete message observing the specified protocol version.
//
// This is part of the wtwire.Message interface.
func (t *StateUpdateReply) MaxPayloadLength(uint32) uint32 {
return 4
}