Fix a possible net ride.

git-svn-id: file:///home/klmitch/undernet-ircu/undernet-ircu-svn/ircu2/branches/u2_10_12_branch@1575 c9e4aea6-c8fd-4c43-8297-357d70d61c8c

diff --git a/ChangeLog b/ChangeLog
index ecf4f4a90648300b8131ebb3c6a71a691da0f082..e1738f0cbc0965db997d91ba07fc41752b44e8ca 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2005-12-13  Michael Poole <mdpoole@troilus.org>
+
+       * ircd/m_join.c (ms_join): Prevent net rides allowed by moving the
+       channel timestamp backwards in time without deopping current ops.
+       (Reported by Wouter Coekaerts.)
+
 2005-12-13  Michael Poole <mdpoole@troilus.org>
 
        * doc/example.conf: Remove extraneous "Other" Client block.

diff --git a/ircd/m_join.c b/ircd/m_join.c
index 3a22b494907909f973ac9ee9bff7d9a9e29b6ba5..7bd6b1a5cb6b06a3084d79c9e122ed9a4556974c 100644 (file)
--- a/ircd/m_join.c
+++ b/ircd/m_join.c
@@ -363,9 +363,37 @@ int ms_join(struct Client *cptr, struct Client *sptr, int parc, char *parv[])
          by one when someone joins an existing, but empty, channel.
          However, this is only necessary when the channel is still
          empty (also here) and when this channel doesn't have +A set.
+
+         To prevent this from allowing net-rides on the channel, we
+         clear all ops from the channel.
+
+         (Scenario for a net ride: c1 - s1 - s2 - c2, with c1 the only
+         user in the channel; c1 parts and rejoins, gaining ops.
+         Before s2 sees c1's part, c2 joins the channel and parts
+         immediately.  s1 sees c1 part, c1 create, c2 join, c2 part;
+         c2's join resets the timestamp.  s2 sees c2 join, c2 part, c1
+         part, c1 create; but since s2 sees the channel as a zannel or
+         non-existent, it does not bounce the create with the newer
+         timestamp.)
       */
       if (creation && creation - ((!chptr->mode.apass[0] && chptr->users == 0) ? 1 : 0) <= chptr->creationtime)
+      {
+        struct Membership *member;
+        struct ModeBuf mbuf;
+
        chptr->creationtime = creation;
+        /* Deop the current ops.  (This will go in both directions on
+         * the network, and revise the channel timestamp as it goes,
+         * avoiding further traffic due to the JOIN.)
+         */
+        modebuf_init(&mbuf, sptr, cptr, chptr, MODEBUF_DEST_CHANNEL | MODEBUF_DEST_HACK3 | MODEBUF_DEST_SERVER);
+        for (member = chptr->members; member; member = member->next_member)
+        {
+          if (IsChanOp(member))
+            modebuf_mode_client(&mbuf, MODE_DEL | MODE_CHANOP, member->user, OpLevel(member));
+        }
+        modebuf_flush(&mbuf);
+      }
     }
 
     joinbuf_join(&join, chptr, flags);