From 9c8caae67d31ae8c97547f8076c2229a97f51532 Mon Sep 17 00:00:00 2001
From: Al Beano <albino@autistici.org>
Date: Fri, 7 Apr 2017 22:58:03 +0100
Subject: [PATCH] Validate nicknames

---
 source/ircd/connection.d |  6 ++++++
 source/ircd/server.d     | 16 ++++++++++++++--
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/source/ircd/connection.d b/source/ircd/connection.d
index dd6c8a9..0598f25 100644
--- a/source/ircd/connection.d
+++ b/source/ircd/connection.d
@@ -203,6 +203,12 @@ class Connection
 			return;
 		}
 
+                if(!_server.isValidNick(newNick))
+                {
+                        send(Message(_server.name, "432", [nick, newNick, "Erroneous nickname"]));
+                        return;
+                }
+
 		if(nick !is null)
 		{
 			sendToPeers(Message(nick, "NICK", [newNick]));
diff --git a/source/ircd/server.d b/source/ircd/server.d
index 2469f81..3ad0167 100644
--- a/source/ircd/server.d
+++ b/source/ircd/server.d
@@ -76,8 +76,20 @@ class Server
 
 	static bool isValidNick(string name)
 	{
-		//TODO: Use the real rules
-		return !name.startsWith('#') && !name.startsWith('&') && name.length <= 9;
+                import std.ascii : digits, letters;
+
+                if(name.length > 9)
+                        return false;
+                foreach(i, c; name)
+                {
+                        auto allowed = letters ~ "[]\\`_^{|}";
+                        if(i > 0)
+                                allowed = allowed ~ digits ~ "-";
+                
+                        if (!allowed.canFind(c))
+                                return false;
+                }
+                return true;
 	}
 
 	bool isNickAvailable(string nick)