From 2fe0a57e430796cdec489817a35b3e4dee790eb1 Mon Sep 17 00:00:00 2001
From: Gregory Anders <greg@gpanders.com>
Date: Wed, 9 Jun 2021 13:25:15 -0600
Subject: [PATCH] Forward MOTD messages downstream

The first MOTD upon connection is ignored, but subsequent MOTD messages
(requested by the "MOTD" message from the client, typically using a
/motd command) are forwarded.
---
 downstream.go |  2 +-
 upstream.go   | 29 ++++++++++++++++++++++++++++-
 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/downstream.go b/downstream.go
index e263054..8e94095 100644
--- a/downstream.go
+++ b/downstream.go
@@ -1105,7 +1105,7 @@ func (dc *downstreamConn) welcome() error {
 	dc.SendMessage(&irc.Message{
 		Prefix:  dc.srv.prefix(),
 		Command: irc.ERR_NOMOTD,
-		Params:  []string{dc.nick, "No MOTD"},
+		Params:  []string{dc.nick, "Use /motd to read the message of the day"},
 	})
 
 	dc.updateNick()
diff --git a/upstream.go b/upstream.go
index c812ef1..1f42a24 100644
--- a/upstream.go
+++ b/upstream.go
@@ -103,6 +103,8 @@ type upstreamConn struct {
 
 	// set of LIST commands in progress, per downstream
 	pendingLISTDownstreamSet map[uint64]struct{}
+
+	gotMotd bool
 }
 
 func connectToUpstream(network *network) (*upstreamConn, error) {
@@ -662,6 +664,21 @@ func (uc *upstreamConn) handleMessage(msg *irc.Message) error {
 			uc.network.updateCasemapping(casemapRFC1459)
 			uc.nickCM = uc.network.casemap(uc.nick)
 		}
+
+		if !uc.gotMotd {
+			// Ignore the initial MOTD upon connection, but forward
+			// subsequent MOTD messages downstream
+			uc.gotMotd = true
+			return nil
+		}
+
+		uc.forEachDownstreamByID(downstreamID, func (dc *downstreamConn) {
+			dc.SendMessage(&irc.Message {
+				Prefix: uc.srv.prefix(),
+				Command: msg.Command,
+				Params: msg.Params,
+			})
+		})
 	case "BATCH":
 		var tag string
 		if err := parseMessageParams(msg, &tag); err != nil {
@@ -1421,7 +1438,17 @@ func (uc *upstreamConn) handleMessage(msg *irc.Message) error {
 	case irc.RPL_LUSERCLIENT, irc.RPL_LUSEROP, irc.RPL_LUSERUNKNOWN, irc.RPL_LUSERCHANNELS, irc.RPL_LUSERME:
 		// Ignore
 	case irc.RPL_MOTDSTART, irc.RPL_MOTD:
-		// Ignore
+		if !uc.gotMotd {
+			return nil
+		}
+
+		uc.forEachDownstreamByID(downstreamID, func (dc *downstreamConn) {
+			dc.SendMessage(&irc.Message {
+				Prefix: uc.srv.prefix(),
+				Command: msg.Command,
+				Params: msg.Params,
+			})
+		})
 	case irc.RPL_LISTSTART:
 		// Ignore
 	case rpl_localusers, rpl_globalusers: