From ca2ba56d82d5fdd959cceaa68eee3722fe45f4f0 Mon Sep 17 00:00:00 2001
From: Bram Matthys <syzop@vulnscan.org>
Date: Sat, 25 Apr 2020 17:01:41 +0200
Subject: [PATCH] Add is_invited(client, channel) function.

---
 include/h.h                        |  3 ++-
 src/channel.c                      | 14 ++++++++++++++
 src/modules/chanmodes/secureonly.c |  7 +++----
 src/modules/join.c                 | 19 +++++--------------
 4 files changed, 24 insertions(+), 19 deletions(-)

diff --git a/include/h.h b/include/h.h
index 2d4cfc091..27596f3e0 100644
--- a/include/h.h
+++ b/include/h.h
@@ -174,7 +174,6 @@ extern void set_snomask(Client *client, char *snomask);
 extern char *get_snomask_string(Client *client);
 extern int check_tkls(Client *cptr);
 /* for services */
-extern void del_invite(Client *, Channel *);
 extern void send_user_joins(Client *, Client *);
 extern int valid_channelname(const char *);
 extern int valid_server_name(char *name);
@@ -623,6 +622,8 @@ extern char *spamfilter_inttostring_long(int v);
 extern Channel *get_channel(Client *cptr, char *chname, int flag);
 extern MODVAR char backupbuf[];
 extern void add_invite(Client *, Client *, Channel *, MessageTag *);
+extern void del_invite(Client *, Channel *);
+extern int is_invited(Client *client, Channel *channel);
 extern void channel_modes(Client *cptr, char *mbuf, char *pbuf, size_t mbuf_size, size_t pbuf_size, Channel *channel);
 extern MODVAR char modebuf[BUFSIZE], parabuf[BUFSIZE];
 extern int op_can_override(char *acl, Client *client,Channel *channel,void* extra);
diff --git a/src/channel.c b/src/channel.c
index a2ce6529a..ddb48747f 100644
--- a/src/channel.c
+++ b/src/channel.c
@@ -1031,6 +1031,20 @@ void del_invite(Client *client, Channel *channel)
 		}
 }
 
+/** Is the user 'client' invited to channel 'channel' by a chanop?
+ * @param client	The client who was invited
+ * @param channel	The channel to which the person was invited
+ */
+int is_invited(Client *client, Channel *channel)
+{
+	Link *lp;
+
+	for (lp = client->user->invited; lp; lp = lp->next)
+		if (lp->value.channel == channel)
+			return 1;
+	return 0;
+}
+
 /** Subtract one user from channel i. Free the channel if it became empty.
  * @param channel The channel
  * @returns 1 if the channel was freed, 0 if the channel still exists.
diff --git a/src/modules/chanmodes/secureonly.c b/src/modules/chanmodes/secureonly.c
index 0330e701e..9d3bd68ed 100644
--- a/src/modules/chanmodes/secureonly.c
+++ b/src/modules/chanmodes/secureonly.c
@@ -140,11 +140,10 @@ int secureonly_check_join(Client *client, Channel *channel, char *key, char *par
 			/* if the channel is +z we still allow an ircop to bypass it
 			 * if they are invited.
 			 */
-			for (lp = client->user->invited; lp; lp = lp->next)
-				if (lp->value.channel == channel)
-					return HOOK_CONTINUE;
+			if (is_invited(client, channel))
+				return HOOK_CONTINUE;
 		}
-		return (ERR_SECUREONLYCHAN);
+		return ERR_SECUREONLYCHAN;
 	}
 	return 0;
 }
diff --git a/src/modules/join.c b/src/modules/join.c
index c50837cb0..334256e00 100644
--- a/src/modules/join.c
+++ b/src/modules/join.c
@@ -113,9 +113,8 @@ int _can_join(Client *client, Channel *channel, char *key, char *parv[])
 	if (banned && j == HOOK_DENY)
 		return (ERR_BANNEDFROMCHAN);
 
-	for (lp = client->user->invited; lp; lp = lp->next)
-		if (lp->value.channel == channel)
-			return 0;
+	if (is_invited(client, channel))
+		return 0; /* allowed */
 
         if (channel->users >= channel->mode.limit)
         {
@@ -515,20 +514,12 @@ void _do_join(Client *client, int parc, char *parv[])
 			    !strcasecmp(name, SPAMFILTER_VIRUSCHAN) &&
 			    !ValidatePermissionsForPath("immune:server-ban:viruschan",client,NULL,NULL,NULL) && !spamf_ugly_vchanoverride)
 			{
-				int invited = 0;
-				Link *lp;
 				Channel *channel = find_channel(name, NULL);
 				
-				if (channel)
+				if (!channel || !is_invited(client, channel))
 				{
-					for (lp = client->user->invited; lp; lp = lp->next)
-						if (lp->value.channel == channel)
-							invited = 1;
-				}
-				if (!invited)
-				{
-					sendnotice(client, "*** Cannot join '%s' because it's the virus-help-channel which is "
-					                 "reserved for infected users only", name);
+					sendnotice(client, "*** Cannot join '%s' because it's the virus-help-channel "
+					                   "which is reserved for infected users only", name);
 					continue;
 				}
 			}