From 9fd4ff766e003daa94f31ff46ea49c6a33f41ff9 Mon Sep 17 00:00:00 2001
From: Yaacov Akiba Slama <ya@slamail.org>
Date: Mon, 23 Nov 2020 15:17:10 +0200
Subject: [PATCH] Add support for receiving sendaddrv2 message from a peer

---
 wire/message.go       |  4 ++++
 wire/msgsendaddrv2.go | 42 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 46 insertions(+)
 create mode 100644 wire/msgsendaddrv2.go

diff --git a/wire/message.go b/wire/message.go
index eae1cf88de..6d3147a81d 100644
--- a/wire/message.go
+++ b/wire/message.go
@@ -57,6 +57,7 @@ const (
 	CmdCFilter      = "cfilter"
 	CmdCFHeaders    = "cfheaders"
 	CmdCFCheckpt    = "cfcheckpt"
+	CmdSendAddrV2   = "sendaddrv2"
 )
 
 // MessageEncoding represents the wire message encoding format to be used.
@@ -99,6 +100,9 @@ func makeEmptyMessage(command string) (Message, error) {
 	case CmdVerAck:
 		msg = &MsgVerAck{}
 
+	case CmdSendAddrV2:
+		msg = &MsgSendAddrV2{}
+
 	case CmdGetAddr:
 		msg = &MsgGetAddr{}
 
diff --git a/wire/msgsendaddrv2.go b/wire/msgsendaddrv2.go
new file mode 100644
index 0000000000..4a459c1a8e
--- /dev/null
+++ b/wire/msgsendaddrv2.go
@@ -0,0 +1,42 @@
+package wire
+
+import (
+	"io"
+)
+
+// MsgSendAddrV2 defines a bitcoin verack message which is used for a peer to
+// signals support for receiving ADDRV2 messages (BIP155). It implements the
+// the Message interface.
+//
+// This message has no payload.
+type MsgSendAddrV2 struct{}
+
+// BtcDecode decodes r using the bitcoin protocol encoding into the receiver.
+// This is part of the Message interface implementation.
+func (msg *MsgSendAddrV2) BtcDecode(r io.Reader, pver uint32, enc MessageEncoding) error {
+	return nil
+}
+
+// BtcEncode encodes the receiver to w using the bitcoin protocol encoding.
+// This is part of the Message interface implementation.
+func (msg *MsgSendAddrV2) BtcEncode(w io.Writer, pver uint32, enc MessageEncoding) error {
+	return nil
+}
+
+// Command returns the protocol command string for the message.  This is part
+// of the Message interface implementation.
+func (msg *MsgSendAddrV2) Command() string {
+	return CmdSendAddrV2
+}
+
+// MaxPayloadLength returns the maximum length the payload can be for the
+// receiver.  This is part of the Message interface implementation.
+func (msg *MsgSendAddrV2) MaxPayloadLength(pver uint32) uint32 {
+	return 0
+}
+
+// NewMsgSendAddrV2 returns a new bitcoin verack message that conforms to the
+// Message interface.
+func NewMsgSendAddrV2() *MsgSendAddrV2 {
+	return &MsgSendAddrV2{}
+}