From fdd4857c1dba20c8191af9d1660ef8378d181ca0 Mon Sep 17 00:00:00 2001
From: jess <github@lolnerd.net>
Date: Mon, 25 Jan 2021 05:00:34 +0000
Subject: [PATCH] /accept list should track nick changes when you share
 channels (#96)

* move has_common_channel to s_user.c

* don't remove clients from /accept on NICK when there's a common channel

Co-authored-by: Ed Kellett <e@kellett.im>
---
 include/s_user.h      |  2 ++
 ircd/s_user.c         | 17 +++++++++++++++++
 modules/core/m_nick.c | 20 +++++++++++++++++---
 modules/um_callerid.c | 16 ----------------
 4 files changed, 36 insertions(+), 19 deletions(-)

diff --git a/include/s_user.h b/include/s_user.h
index e0f41aa3..9fb6f7ed 100644
--- a/include/s_user.h
+++ b/include/s_user.h
@@ -54,3 +54,5 @@ extern void construct_umodebuf(void);
 extern void oper_up(struct Client *, struct oper_conf *);
 
 #endif
+
+extern bool has_common_channel(struct Client *source_p, struct Client *target_p);
diff --git a/ircd/s_user.c b/ircd/s_user.c
index 0fa78ba4..7ea20e7f 100644
--- a/ircd/s_user.c
+++ b/ircd/s_user.c
@@ -1644,3 +1644,20 @@ change_nick_user_host(struct Client *target_p,	const char *nick, const char *use
 		del_all_accepts(target_p);
 	}
 }
+
+bool
+has_common_channel(struct Client *source_p, struct Client *target_p)
+{
+        rb_dlink_node *ps, *pt;
+        struct membership *ms, *mt;
+        struct Channel *chptr;
+
+        ITER_COMM_CHANNELS(ps, pt, source_p->user->channel.head, target_p->user->channel.head, ms, mt, chptr)
+        {
+                if (ms != NULL && mt != NULL)
+                        return true;
+        }
+
+        return false;
+}
+
diff --git a/modules/core/m_nick.c b/modules/core/m_nick.c
index a5b94d59..890d0c2b 100644
--- a/modules/core/m_nick.c
+++ b/modules/core/m_nick.c
@@ -712,8 +712,11 @@ change_local_nick(struct Client *client_p, struct Client *source_p,
 	{
 		target_p = ptr->data;
 
-		rb_dlinkFindDestroy(source_p, &target_p->localClient->allow_list);
-		rb_dlinkDestroy(ptr, &source_p->on_allow_list);
+		if (!has_common_channel(source_p, target_p))
+		{
+			rb_dlinkFindDestroy(source_p, &target_p->localClient->allow_list);
+			rb_dlinkDestroy(ptr, &source_p->on_allow_list);
+		}
 	}
 
 	snprintf(note, sizeof(note), "Nick: %s", nick);
@@ -729,6 +732,8 @@ static void
 change_remote_nick(struct Client *client_p, struct Client *source_p,
 		   time_t newts, const char *nick, int dosend)
 {
+	struct Client *target_p;
+	rb_dlink_node *ptr, *next_ptr;
 	struct nd_entry *nd;
 	int samenick = irccmp(source_p->name, nick) ? 0 : 1;
 	hook_cdata hook_info;
@@ -771,7 +776,16 @@ change_remote_nick(struct Client *client_p, struct Client *source_p,
 		monitor_signon(source_p);
 
 	/* remove all accepts pointing to the client */
-	del_all_accepts(source_p);
+	RB_DLINK_FOREACH_SAFE(ptr, next_ptr, source_p->on_allow_list.head)
+	{
+		target_p = ptr->data;
+
+		if (!has_common_channel(source_p, target_p))
+		{
+			rb_dlinkFindDestroy(source_p, &target_p->localClient->allow_list);
+			rb_dlinkDestroy(ptr, &source_p->on_allow_list);
+		}
+	}
 }
 
 static void
diff --git a/modules/um_callerid.c b/modules/um_callerid.c
index 56394986..2fa47db4 100644
--- a/modules/um_callerid.c
+++ b/modules/um_callerid.c
@@ -87,22 +87,6 @@ um_callerid_moddeinit(void)
 static const char um_callerid_desc[] =
 	"Provides usermodes +g and +G which restrict messages from unauthorized users.";
 
-static bool
-has_common_channel(struct Client *source_p, struct Client *target_p)
-{
-	rb_dlink_node *ps, *pt;
-	struct membership *ms, *mt;
-	struct Channel *chptr;
-
-	ITER_COMM_CHANNELS(ps, pt, source_p->user->channel.head, target_p->user->channel.head, ms, mt, chptr)
-	{
-		if (ms != NULL && mt != NULL)
-			return true;
-	}
-
-	return false;
-}
-
 static bool
 allow_message(struct Client *source_p, struct Client *target_p)
 {