/*
 *  ircd-hybrid: an advanced Internet Relay Chat Daemon(ircd).
 *  m_svinfo.c: Sends TS information for clock & compatibility checks.
 *
 *  Copyright (C) 2002 by the past and present ircd coders, and others.
 *
 *  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 2 of the License, 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 *  USA
 *
 *  $Id: m_svinfo.c,v 1.5 2003/10/31 16:31:00 dbharris Exp $
 */
#include "stdinc.h"
#include "handlers.h"
#include "client.h"
#include "common.h"     /* TRUE bleah */
#include "irc_string.h"
#include "ircd.h"
#include "numeric.h"
#include "send.h"
#include "s_conf.h"
#include "s_log.h"
#include "msg.h"
#include "parse.h"
#include "modules.h"


static void ms_svinfo(struct Client*, struct Client*, int, char**);

struct Message svinfo_msgtab = {
  "SVINFO", 0, 0, 4, 0, MFLG_SLOW, 0,
  {m_unregistered, m_ignore, ms_svinfo, m_ignore, m_ignore}
};

#ifndef STATIC_MODULES
void
_modinit(void)
{
  mod_add_cmd(&svinfo_msgtab);
}

void
_moddeinit(void)
{
  mod_del_cmd(&svinfo_msgtab);
}

const char *_version = "$Revision: 1.5 $";
#endif
/*
 * ms_svinfo - SVINFO message handler
 *      parv[0] = sender prefix
 *      parv[1] = TS_CURRENT for the server
 *      parv[2] = TS_MIN for the server
 *      parv[3] = server is standalone or connected to non-TS only
 *      parv[4] = server's idea of UTC time
 */
static void
ms_svinfo(struct Client *client_p, struct Client *source_p,
	  int parc, char *parv[])
{
  time_t deltat;
  time_t theirtime;

  if (MyConnect(source_p) && IsUnknown(source_p))
  {
    exit_client(source_p, source_p, source_p, "Need SERVER before SVINFO");
    return;
  }

  if (!IsServer(source_p) || !MyConnect(source_p) || parc < 5)
    return;

  if (TS_CURRENT < atoi(parv[2]) || atoi(parv[1]) < TS_MIN)
    {
      /*
       * a server with the wrong TS version connected; since we're
       * TS_ONLY we can't fall back to the non-TS protocol so
       * we drop the link  -orabidoo
       */
      sendto_gnotice_flags(UMODE_ALL, L_ALL, me.name, &me, NULL,
            "Link %s dropped, wrong TS protocol version (%s,%s)",
            get_client_name(source_p, SHOW_IP), parv[1], parv[2]);
      exit_client(source_p, source_p, source_p, "Incompatible TS version");
      return;
    }

  /*
   * since we're here, might as well set CurrentTime while we're at it
   */
  set_time(); 
  theirtime = atol(parv[4]);
  deltat = abs(theirtime - CurrentTime);

  if (deltat > ConfigFileEntry.ts_max_delta)
    {
      sendto_gnotice_flags(UMODE_ALL, L_ALL, me.name, &me, NULL,
          "Link %s dropped, excessive TS delta (my TS=%lu, their TS=%lu, delta=%d)",
          get_client_name(source_p, SHOW_IP),
          (unsigned long) CurrentTime,
          (unsigned long) theirtime,
          (int) deltat);
      ilog(L_NOTICE,
          "Link %s dropped, excessive TS delta (my TS=%lu, their TS=%lu, delta=%d)",
          get_client_name(source_p, SHOW_IP),
          (unsigned long) CurrentTime,
          (unsigned long) theirtime,
          (int) deltat);
      exit_client(source_p, source_p, source_p, "Excessive TS delta");
      return;
    }

  if (deltat > ConfigFileEntry.ts_warn_delta)
    { 
      sendto_gnotice_flags(UMODE_ALL, L_ALL, me.name, &me, NULL,
                "Link %s notable TS delta (my TS=%lu, their TS=%lu, delta=%d)",
                source_p->name,
                (unsigned long) CurrentTime,
                (unsigned long) theirtime,
                (int) deltat);
    }
}
