From a438c34489ce5e109d1dfac413fbed5042365e15 Mon Sep 17 00:00:00 2001
From: Simon Ser <contact@emersion.fr>
Date: Thu, 3 Mar 2022 10:54:21 +0100
Subject: [PATCH] downstream: disallow '.' in nicknames

See [1] and [2].

[1]: https://github.com/ircdocs/modern-irc/pull/148
[2]: https://github.com/ergochat/ergo/blob/eff6dd242b7dc1382ec555929bfbe536f4fe6b8b/irc/strings.go#L29
---
 downstream.go | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/downstream.go b/downstream.go
index 4c08fd1..9f018d3 100644
--- a/downstream.go
+++ b/downstream.go
@@ -215,7 +215,8 @@ func updateNetworkAttrs(record *Network, attrs irc.Tags, subcommand string) erro
 //     '?' breaks masks
 //     '$' breaks server masks in PRIVMSG/NOTICE
 //     ',' breaks lists
-const illegalNickChars = " :@!*?$,"
+//     '.' is reserved for server names
+const illegalNickChars = " :@!*?$,."
 
 // permanentDownstreamCaps is the list of always-supported downstream
 // capabilities.