From ef57f7fb5ea87458c91f26ffe9918f842214e463 Mon Sep 17 00:00:00 2001
From: Jilles Tjoelker <jilles@stack.nl>
Date: Sun, 27 Jul 2008 22:17:46 +0200
Subject: [PATCH] Remove user@server messages to local users. These are
 unreliable in general and only useful for violating certain restrictions.
 Sending such messages to remote servers is still possible, for securely
 messaging pseudoservers whether service{}'ed or not. The special oper-only
 syntax opers@server remains as well.

---
 modules/core/m_message.c | 71 +++++-----------------------------------
 1 file changed, 9 insertions(+), 62 deletions(-)

diff --git a/modules/core/m_message.c b/modules/core/m_message.c
index 0264a519..16a40a4f 100644
--- a/modules/core/m_message.c
+++ b/modules/core/m_message.c
@@ -93,7 +93,6 @@ static int build_target_list(int p_or_n, const char *command,
 static int flood_attack_client(int p_or_n, struct Client *source_p, struct Client *target_p);
 static int flood_attack_channel(int p_or_n, struct Client *source_p,
 				struct Channel *chptr, char *chname);
-static struct Client *find_userhost(const char *, const char *, int *);
 
 #define ENTITY_NONE    0
 #define ENTITY_CHANNEL 1
@@ -893,7 +892,6 @@ handle_special(int p_or_n, const char *command, struct Client *client_p,
 	       struct Client *source_p, const char *nick, const char *text)
 {
 	struct Client *target_p;
-	char *host;
 	char *server;
 	char *s;
 	int count;
@@ -931,39 +929,23 @@ handle_special(int p_or_n, const char *command, struct Client *client_p,
 			return;
 		}
 
-		*server = '\0';
-
-		if((host = strchr(nick, '%')) != NULL)
-			*host++ = '\0';
-
 		/* Check if someones msg'ing opers@our.server */
-		if(strcmp(nick, "opers") == 0)
+		if(strncmp(nick, "opers@", 6) == 0)
 		{
 			sendto_realops_snomask(SNO_GENERAL, L_ALL, "To opers: From: %s: %s",
 					     source_p->name, text);
 			return;
 		}
 
-		/*
-		 * Look for users which match the destination host
-		 * (no host == wildcard) and if one and one only is
-		 * found connected to me, deliver message!
+		/* This was not very useful except for bypassing certain
+		 * restrictions. Note that we still allow sending to
+		 * remote servers this way, for messaging pseudoservers
+		 * securely whether they have a service{} block or not.
+		 * -- jilles
 		 */
-		target_p = find_userhost(nick, host, &count);
-
-		if(target_p != NULL)
-		{
-			if(server != NULL)
-				*server = '@';
-			if(host != NULL)
-				*--host = '%';
-
-			if(count == 1)
-				sendto_anywhere(target_p, source_p, command, ":%s", text);
-			else
-				sendto_one(source_p, form_str(ERR_TOOMANYTARGETS),
-					   get_id(&me, source_p), get_id(source_p, source_p), nick);
-		}
+		sendto_one_numeric(source_p, ERR_NOSUCHNICK,
+				   form_str(ERR_NOSUCHNICK), nick);
+		return;
 	}
 
 	/*
@@ -1014,38 +996,3 @@ handle_special(int p_or_n, const char *command, struct Client *client_p,
 		return;
 	}
 }
-
-/*
- * find_userhost - find a user@host (server or user).
- * inputs       - user name to look for
- *              - host name to look for
- *		- pointer to count of number of matches found
- * outputs	- pointer to client if found
- *		- count is updated
- * side effects	- none
- *
- */
-static struct Client *
-find_userhost(const char *user, const char *host, int *count)
-{
-	struct Client *c2ptr;
-	struct Client *res = NULL;
-	char *u = LOCAL_COPY(user);
-	rb_dlink_node *ptr;
-	*count = 0;
-	if(collapse(u) != NULL)
-	{
-		RB_DLINK_FOREACH(ptr, global_client_list.head)
-		{
-			c2ptr = ptr->data;
-			if(!MyClient(c2ptr))	/* implies mine and an user */
-				continue;
-			if((!host || match(host, c2ptr->host)) && irccmp(u, c2ptr->username) == 0)
-			{
-				(*count)++;
-				res = c2ptr;
-			}
-		}
-	}
-	return (res);
-}