Fix bugs relating to joining zannels for a quick release.

[ircu2.10.12-pk.git] / ircd / m_create.c

diff --git a/ircd/m_create.c b/ircd/m_create.c
index 8219f09e0c4a556826dbca7ee9594f89db3f8876..6cb3db2c80d6673a863173355e232a4a7795172a 100644 (file)
--- a/ircd/m_create.c
+++ b/ircd/m_create.c
@@ -168,7 +168,27 @@ int ms_create(struct Client* cptr, struct Client* sptr, int parc, char* parv[])
       /* Check if we need to bounce a mode */
       if (TStime() - chanTS > TS_LAG_TIME ||
          (chptr->creationtime && chanTS > chptr->creationtime &&
-          chptr->creationtime != MAGIC_REMOTE_JOIN_TS)) {
+          chptr->creationtime != MAGIC_REMOTE_JOIN_TS &&
+          /* Accept CREATE for zannels. This is only really necessary on a network
+             with servers prior to 2.10.12.02: we just accept their TS and ignore
+             the fact that it was a zannel. The influence of this on a network
+             that is completely 2.10.12.03 or higher is neglectable: Normally
+             a server only sends a CREATE after first sending a DESTRUCT. Thus,
+             by receiving a CREATE for a zannel one of two things happened:
+             1. The DESTRUCT was sent during a net.break; this could mean that
+                our zannel is at the verge of expiring too, it should have been
+                destructed. It is correct to copy the newer TS now, all modes
+                already have been reset, so it will be as if it was destructed
+                and immediately recreated. In order to avoid desyncs of modes,
+                we don't accept a CREATE for channels that have +A set.
+             2. The DESTRUCT passed, then someone created the channel on our
+                side and left it again. In this situation we have a near
+                simultaneous creation on two servers; the person on our side
+                already left within the time span of a message propagation.
+                The channel will therefore be less than 48 hours old and no
+                'protection' is necessary.
+           */
+          !(chptr->users == 0 && !chptr->mode.apass[0]))) {
        modebuf_init(&mbuf, sptr, cptr, chptr,
                     (MODEBUF_DEST_SERVER |  /* Send mode to server */
                      MODEBUF_DEST_HACK2  |  /* Send a HACK(2) message */