+/*
+ * IRC - Internet Relay Chat, ircd/m_create.c
+ * Copyright (C) 1990 Jarkko Oikarinen and
+ * University of Oulu, Computing Center
+ *
+ * See file AUTHORS in IRC package for additional names of
+ * the programmers.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 1, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * $Id$
+ */
+
+/*
+ * m_functions execute protocol messages on this server:
+ *
+ * cptr is always NON-NULL, pointing to a *LOCAL* client
+ * structure (with an open socket connected!). This
+ * identifies the physical socket where the message
+ * originated (or which caused the m_function to be
+ * executed--some m_functions may call others...).
+ *
+ * sptr is the source of the message, defined by the
+ * prefix part of the message if present. If not
+ * or prefix not found, then sptr==cptr.
+ *
+ * (!IsServer(cptr)) => (cptr == sptr), because
+ * prefixes are taken *only* from servers...
+ *
+ * (IsServer(cptr))
+ * (sptr == cptr) => the message didn't
+ * have the prefix.
+ *
+ * (sptr != cptr && IsServer(sptr) means
+ * the prefix specified servername. (?)
+ *
+ * (sptr != cptr && !IsServer(sptr) means
+ * that message originated from a remote
+ * user (not local).
+ *
+ * combining
+ *
+ * (!IsServer(sptr)) means that, sptr can safely
+ * taken as defining the target structure of the
+ * message in this server.
+ *
+ * *Always* true (if 'parse' and others are working correct):
+ *
+ * 1) sptr->from == cptr (note: cptr->from == cptr)
+ *
+ * 2) MyConnect(sptr) <=> sptr == cptr (e.g. sptr
+ * *cannot* be a local connection, unless it's
+ * actually cptr!). [MyConnect(x) should probably
+ * be defined as (x == x->from) --msa ]
+ *
+ * parc number of variable parameter strings (if zero,
+ * parv is allowed to be NULL)
+ *
+ * parv a NULL terminated list of parameter pointers,
+ *
+ * parv[0], sender (prefix string), if not present
+ * this points to an empty string.
+ * parv[1]...parv[parc-1]
+ * pointers to additional parameters
+ * parv[parc] == NULL, *always*
+ *
+ * note: it is guaranteed that parv[0]..parv[parc-1] are all
+ * non-NULL pointers.
+ */
+#include "config.h"
+
+#include "channel.h"
+#include "client.h"
+#include "hash.h"
+#include "ircd.h"
+#include "ircd_log.h"
+#include "ircd_reply.h"
+#include "ircd_string.h"
+#include "msg.h"
+#include "numeric.h"
+#include "numnicks.h"
+#include "s_debug.h"
+#include "s_misc.h"
+#include "s_user.h"
+#include "send.h"
+
+/* #include <assert.h> -- Now using assert in ircd_log.h */
+#include <stdlib.h>
+#include <string.h>
+
+/*
+ * ms_create - server message handler
+ */
+int ms_create(struct Client* cptr, struct Client* sptr, int parc, char* parv[])
+{
+ time_t chanTS; /* channel creation time */
+ char *p; /* strtok state */
+ char *name; /* channel name */
+ struct Channel *chptr; /* channel */
+ struct JoinBuf join; /* join and create buffers */
+ struct JoinBuf create;
+ struct ModeBuf mbuf; /* a mode buffer */
+ int badop; /* a flag */
+
+ if (IsServer(sptr))
+ return protocol_violation(sptr,"%s tried to CREATE a channel", cli_name(sptr));
+
+ /* sanity checks: Only accept CREATE messages from servers */
+ if (parc < 3 || *parv[2] == '\0')
+ return need_more_params(sptr,"CREATE");
+
+ chanTS = atoi(parv[2]);
+
+ /* A create that didn't appear during a burst has that servers idea of
+ * the current time. Use it for lag calculations.
+ */
+ if (!IsBurstOrBurstAck(sptr) && 0 != chanTS)
+ cli_serv(cli_user(sptr)->server)->lag = TStime() - chanTS;
+
+ /* If this server is >1 minute fast, warn */
+ if (TStime() - chanTS<-60)
+ {
+ static time_t rate;
+ sendto_opmask_butone_ratelimited(0, SNO_NETWORK, &rate,
+ "Timestamp drift from %C (%is); issuing "
+ "SETTIME to correct this",
+ cli_user(sptr)->server,
+ chanTS - TStime());
+ /* Now issue a SETTIME to resync. If we're in the wrong, our
+ * (RELIABLE_CLOCK) hub will bounce a SETTIME back to us.
+ */
+ sendcmdto_prio_one(&me, CMD_SETTIME, cli_user(sptr)->server,
+ "%Tu %C", TStime(), cli_user(sptr)->server);
+ }
+
+ joinbuf_init(&join, sptr, cptr, JOINBUF_TYPE_JOIN, 0, 0);
+ joinbuf_init(&create, sptr, cptr, JOINBUF_TYPE_CREATE, 0, chanTS);
+
+ /* For each channel in the comma separated list: */
+ for (name = ircd_strtok(&p, parv[1], ","); name;
+ name = ircd_strtok(&p, 0, ",")) {
+ badop = 0;
+
+ if (IsLocalChannel(name))
+ continue;
+
+ if ((chptr = FindChannel(name)))
+ {
+ /* Is the remote server confused? */
+ if (find_member_link(chptr, sptr)) {
+ protocol_violation(sptr, "%s tried to CREATE a channel already joined (%s)", cli_name(sptr), chptr->chname);
+ continue;
+ }
+
+ /* Check if we need to bounce a mode */
+ if (TStime() - chanTS > TS_LAG_TIME ||
+ (chptr->creationtime && chanTS > chptr->creationtime &&
+ /* 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 three 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.
+ 3. The source server sent the CREATE while linking,
+ before it got the BURST for our zannel. If this
+ happens, we should reset the channel back to the old
+ timestamp. This can be distinguished from case #1 by
+ checking IsBurstOrBurstAck(cli_user(sptr)->server).
+ */
+ !(chptr->users == 0 && !chptr->mode.apass[0]))) {
+ if (!IsBurstOrBurstAck(cli_user(sptr)->server)) {
+ modebuf_init(&mbuf, sptr, cptr, chptr,
+ (MODEBUF_DEST_SERVER | /* Send mode to server */
+ MODEBUF_DEST_HACK2 | /* Send a HACK(2) message */
+ MODEBUF_DEST_BOUNCE)); /* And bounce the mode */
+
+ modebuf_mode_client(&mbuf, MODE_ADD | MODE_CHANOP, sptr, MAXOPLEVEL + 1);
+
+ modebuf_flush(&mbuf);
+
+ badop = 1;
+ } else if (chanTS > chptr->creationtime + 4) {
+ /* If their handling of the BURST will lead to deopping the
+ * user, have the user join without getting ops (if the
+ * server's handling of the BURST keeps their ops, the channel
+ * will use our timestamp).
+ */
+ badop = 1;
+ }
+
+ if (badop)
+ joinbuf_join(&join, chptr, 0);
+ }
+ }
+ else /* Channel doesn't exist: create it */
+ chptr = get_channel(sptr, name, CGT_CREATE);
+
+ if (!badop) {
+ /* Set (or correct) our copy of the TS */
+ chptr->creationtime = chanTS;
+ joinbuf_join(&create, chptr, CHFL_CHANOP);
+ }
+ }
+
+ joinbuf_flush(&join); /* flush out the joins and creates */
+ joinbuf_flush(&create);
+
+ return 0;
+}