ircd/m_kill.c

   1 /*
   2  * IRC - Internet Relay Chat, ircd/m_kill.c
   3  * Copyright (C) 1990 Jarkko Oikarinen and
   4  *                    University of Oulu, Computing Center
   5  *
   6  * See file AUTHORS in IRC package for additional names of
   7  * the programmers.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 1, or (at your option)
  12  * any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22  *
  23  * $Id: m_kill.c,v 1.31 2005/08/21 13:46:07 entrope Exp $
  24  */
  25
  26 /*
  27  * m_functions execute protocol messages on this server:
  28  *
  29  *    cptr    is always NON-NULL, pointing to a *LOCAL* client
  30  *            structure (with an open socket connected!). This
  31  *            identifies the physical socket where the message
  32  *            originated (or which caused the m_function to be
  33  *            executed--some m_functions may call others...).
  34  *
  35  *    sptr    is the source of the message, defined by the
  36  *            prefix part of the message if present. If not
  37  *            or prefix not found, then sptr==cptr.
  38  *
  39  *            (!IsServer(cptr)) => (cptr == sptr), because
  40  *            prefixes are taken *only* from servers...
  41  *
  42  *            (IsServer(cptr))
  43  *                    (sptr == cptr) => the message didn't
  44  *                    have the prefix.
  45  *
  46  *                    (sptr != cptr && IsServer(sptr) means
  47  *                    the prefix specified servername. (?)
  48  *
  49  *                    (sptr != cptr && !IsServer(sptr) means
  50  *                    that message originated from a remote
  51  *                    user (not local).
  52  *
  53  *            combining
  54  *
  55  *            (!IsServer(sptr)) means that, sptr can safely
  56  *            taken as defining the target structure of the
  57  *            message in this server.
  58  *
  59  *    *Always* true (if 'parse' and others are working correct):
  60  *
  61  *    1)      sptr->from == cptr  (note: cptr->from == cptr)
  62  *
  63  *    2)      MyConnect(sptr) <=> sptr == cptr (e.g. sptr
  64  *            *cannot* be a local connection, unless it's
  65  *            actually cptr!). [MyConnect(x) should probably
  66  *            be defined as (x == x->from) --msa ]
  67  *
  68  *    parc    number of variable parameter strings (if zero,
  69  *            parv is allowed to be NULL)
  70  *
  71  *    parv    a NULL terminated list of parameter pointers,
  72  *
  73  *                    parv[0], sender (prefix string), if not present
  74  *                            this points to an empty string.
  75  *                    parv[1]...parv[parc-1]
  76  *                            pointers to additional parameters
  77  *                    parv[parc] == NULL, *always*
  78  *
  79  *            note:   it is guaranteed that parv[0]..parv[parc-1] are all
  80  *                    non-NULL pointers.
  81  */
  82 #include "config.h"
  83
  84 #include "client.h"
  85 #include "hash.h"
  86 #include "ircd.h"
  87 #include "ircd_features.h"
  88 #include "ircd_log.h"
  89 #include "ircd_reply.h"
  90 #include "ircd_snprintf.h"
  91 #include "ircd_string.h"
  92 #include "msg.h"
  93 #include "numeric.h"
  94 #include "numnicks.h"
  95 #include "s_misc.h"
  96 #include "send.h"
  97 #include "whowas.h"
  98
  99 /* #include <assert.h> -- Now using assert in ircd_log.h */
 100 #include <string.h>
 101
 102 /*
 103  * do_kill - Performs the generic work involved in killing a client
 104  *
 105  */
 106 static int do_kill(struct Client* cptr, struct Client* sptr,
 107                    struct Client* victim, char* inpath, char* path, char* msg)
 108 {
 109   assert(0 != cptr);
 110   assert(0 != sptr);
 111   assert(!IsServer(victim));
 112
 113   /*
 114    * Notify all *local* opers about the KILL (this includes the one
 115    * originating the kill, if from this server--the special numeric
 116    * reply message is not generated anymore).
 117    *
 118    * Note: "victim->name" is used instead of "user" because we may
 119    *       have changed the target because of the nickname change.
 120    */
 121   sendto_opmask_butone(0, IsServer(sptr) ? SNO_SERVKILL : SNO_OPERKILL,
 122                        "Received KILL message for %s. From %s Path: %s!%s %s",
 123                        get_client_name(victim, SHOW_IP), cli_name(sptr),
 124                        inpath, path, msg);
 125   log_write_kill(victim, sptr, inpath, path, msg);
 126
 127   /*
 128    * And pass on the message to other servers. Note, that if KILL
 129    * was changed, the message has to be sent to all links, also
 130    * back.
 131    * Client suicide kills are NOT passed on --SRB
 132    */
 133   if (IsServer(cptr) || !MyConnect(victim)) {
 134     sendcmdto_serv_butone(sptr, CMD_KILL, cptr, "%C :%s!%s %s", victim,
 135                           inpath, path, msg);
 136
 137     /*
 138      * Set FLAG_KILLED. This prevents exit_one_client from sending
 139      * the unnecessary QUIT for this. (This flag should never be
 140      * set in any other place)
 141      */
 142     SetFlag(victim, FLAG_KILLED);
 143   }
 144
 145   /*
 146    * Tell the victim she/he has been zapped, but *only* if
 147    * the victim is on current server--no sense in sending the
 148    * notification chasing the above kill, it won't get far
 149    * anyway (as this user don't exist there any more either)
 150    * In accordance with the new hiding rules, the victim
 151    * always sees the kill as coming from me.
 152    */
 153   if (MyConnect(victim))
 154     sendcmdto_one(feature_bool(FEAT_HIS_KILLWHO) ? &his : sptr, CMD_KILL,
 155                   victim, "%C :%s %s", victim, feature_bool(FEAT_HIS_KILLWHO)
 156                   ? feature_str(FEAT_HIS_SERVERNAME) : cli_name(sptr), msg);
 157   return exit_client_msg(cptr, victim, feature_bool(FEAT_HIS_KILLWHO)
 158                          ? &me : sptr, "Killed (%s %s)",
 159                          feature_bool(FEAT_HIS_KILLWHO) ?
 160                          feature_str(FEAT_HIS_SERVERNAME) : cli_name(sptr),
 161                          msg);
 162 }
 163
 164 /*
 165  * ms_kill - server message handler
 166  *
 167  * NOTE: IsServer(cptr) == true;
 168  *
 169  * parv[0]      = sender prefix
 170  * parv[1]      = kill victim
 171  * parv[parc-1] = kill path
 172  */
 173 int ms_kill(struct Client* cptr, struct Client* sptr, int parc, char* parv[])
 174 {
 175   struct Client* victim;
 176   char*          path;
 177   char*          msg;
 178
 179   assert(0 != cptr);
 180   assert(0 != sptr);
 181   assert(IsServer(cptr));
 182
 183   /*
 184    * XXX - a server sending less than 3 params could really desync
 185    * things
 186    */
 187   if (parc < 3) {
 188     protocol_violation(sptr,"Too few arguments for KILL");
 189     return need_more_params(sptr, "KILL");
 190   }
 191
 192   path = parv[parc - 1];        /* Either defined or NULL (parc >= 3) */
 193
 194   if (!(msg = strchr(path, ' '))) /* Extract out the message */
 195     msg = "(No reason supplied)";
 196   else
 197     *(msg++) = '\0'; /* Remove first character (space) and terminate path */
 198
 199   if (!(victim = findNUser(parv[1]))) {
 200     if (IsUser(sptr))
 201       sendcmdto_one(&me, CMD_NOTICE, sptr, "%C :KILL target disconnected "
 202                     "before I got him :(", sptr);
 203     return 0;
 204   }
 205
 206   /*
 207    * We *can* have crossed a NICK with this numeric... --Run
 208    *
 209    * Note the following situation:
 210    *  KILL SAA -->       X
 211    *  <-- S NICK ... SAA | <-- SAA QUIT <-- S NICK ... SAA <-- SQUIT S
 212    * Where the KILL reaches point X before the QUIT does.
 213    * This would then *still* cause an orphan because the KILL doesn't reach S
 214    * (because of the SQUIT), the QUIT is ignored (because of the KILL)
 215    * and the second NICK ... SAA causes an orphan on the server at the
 216    * right (which then isn't removed when the SQUIT arrives).
 217    * Therefore we still need to detect numeric nick collisions too.
 218    *
 219    * Bounce the kill back to the originator, if the client can't be found
 220    * by the next hop (short lag) the bounce won't propagate further.
 221    */
 222   if (MyConnect(victim)) {
 223     sendcmdto_one(&me, CMD_KILL, cptr, "%C :%s (Ghost 5 Numeric Collided)",
 224                   victim, path);
 225   }
 226   return do_kill(cptr, sptr, victim, cli_name(cptr), path, msg);
 227 }
 228
 229 /*
 230  * mo_kill - oper message handler
 231  *
 232  * NOTE: IsPrivileged(sptr), IsAnOper(sptr) == true
 233  *       IsServer(cptr), IsServer(sptr) == false
 234  *
 235  * parv[0]      = sender prefix
 236  * parv[1]      = kill victim
 237  * parv[parc-1] = kill path
 238  */
 239 int mo_kill(struct Client* cptr, struct Client* sptr, int parc, char* parv[])
 240 {
 241   struct Client* victim;
 242   char*          user;
 243   char           msg[TOPICLEN + 3]; /* (, ), and \0 */
 244
 245   assert(0 != cptr);
 246   assert(0 != sptr);
 247   /*
 248    * oper connection to this server, cptr is always sptr
 249    */
 250   assert(cptr == sptr);
 251   assert(IsAnOper(sptr));
 252
 253   if (parc < 3 || EmptyString(parv[parc - 1]))
 254     return need_more_params(sptr, "KILL");
 255
 256   user = parv[1];
 257   ircd_snprintf(0, msg, sizeof(msg), "(%.*s)", TOPICLEN, parv[parc - 1]);
 258
 259   if (!(victim = FindClient(user))) {
 260     /*
 261      * If the user has recently changed nick, we automatically
 262      * rewrite the KILL for this new nickname--this keeps
 263      * servers in synch when nick change and kill collide
 264      */
 265     if (!(victim = get_history(user, (long)15)))
 266       return send_reply(sptr, ERR_NOSUCHNICK, user);
 267
 268     sendcmdto_one(&me, CMD_NOTICE, sptr, "%C :Changed KILL %s into %s", sptr,
 269                   user, cli_name(victim));
 270   }
 271   if (!HasPriv(sptr, MyConnect(victim) ? PRIV_LOCAL_KILL : PRIV_KILL))
 272     return send_reply(sptr, ERR_NOPRIVILEGES);
 273
 274   if (IsServer(victim) || IsMe(victim)) {
 275     return send_reply(sptr, ERR_CANTKILLSERVER);
 276   }
 277   /*
 278    * if the user is +k, prevent a kill from local user
 279    */
 280   if (IsChannelService(victim))
 281     return send_reply(sptr, ERR_ISCHANSERVICE, "KILL", cli_name(victim));
 282
 283
 284   if (!MyConnect(victim) && !HasPriv(sptr, PRIV_KILL)) {
 285     sendcmdto_one(&me, CMD_NOTICE, sptr, "%C :Nick %s isn't on your server",
 286                   sptr, cli_name(victim));
 287     return 0;
 288   }
 289   return do_kill(cptr, sptr, victim, cli_user(sptr)->host, cli_name(sptr),
 290                  msg);
 291 }