src/listener.c

   1 /*
   2  *  ircd-ratbox: A slightly useful ircd.
   3  *  listener.c: Listens on a port.
   4  *
   5  *  Copyright (C) 1990 Jarkko Oikarinen and University of Oulu, Co Center
   6  *  Copyright (C) 1996-2002 Hybrid Development Team
   7  *  Copyright (C) 2002-2005 ircd-ratbox development team
   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 2 of the License, or
  12  *  (at your option) 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307
  22  *  USA
  23  *
  24  *  $Id: listener.c 3460 2007-05-18 20:31:33Z jilles $
  25  */
  26
  27 #include "stdinc.h"
  28 #include "setup.h"
  29 #include "listener.h"
  30 #include "client.h"
  31 #include "irc_string.h"
  32 #include "sprintf_irc.h"
  33 #include "ircd.h"
  34 #include "ircd_defs.h"
  35 #include "numeric.h"
  36 #include "s_conf.h"
  37 #include "s_newconf.h"
  38 #include "s_stats.h"
  39 #include "send.h"
  40 #include "s_auth.h"
  41 #include "reject.h"
  42 #include "s_conf.h"
  43 #include "hostmask.h"
  44
  45 #ifndef INADDR_NONE
  46 #define INADDR_NONE ((unsigned int) 0xffffffff)
  47 #endif
  48
  49 #if defined(NO_IN6ADDR_ANY) && defined(IPV6)
  50 static const struct in6_addr in6addr_any =
  51 { { { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 } } };
  52 #endif
  53
  54 static listener_t *ListenerPollList = NULL;
  55
  56 static listener_t *
  57 make_listener(struct rb_sockaddr_storage *addr)
  58 {
  59         listener_t *listener = (listener_t *) rb_malloc(sizeof(listener_t));
  60         s_assert(0 != listener);
  61         listener->name = me.name;
  62         listener->F = NULL;
  63
  64         memcpy(&listener->addr, addr, sizeof(struct rb_sockaddr_storage));
  65         listener->next = NULL;
  66         return listener;
  67 }
  68
  69 void
  70 free_listener(listener_t *listener)
  71 {
  72         s_assert(NULL != listener);
  73         if(listener == NULL)
  74                 return;
  75         /*
  76          * remove from listener list
  77          */
  78         if(listener == ListenerPollList)
  79                 ListenerPollList = listener->next;
  80         else
  81         {
  82                 listener_t *prev = ListenerPollList;
  83                 for (; prev; prev = prev->next)
  84                 {
  85                         if(listener == prev->next)
  86                         {
  87                                 prev->next = listener->next;
  88                                 break;
  89                         }
  90                 }
  91         }
  92
  93         /* free */
  94         rb_free(listener);
  95 }
  96
  97 #define PORTNAMELEN 6           /* ":31337" */
  98
  99 /*
 100  * get_listener_name - return displayable listener name and port
 101  * returns "host.foo.org:6667" for a given listener
 102  */
 103 const char *
 104 get_listener_name(const listener_t *listener)
 105 {
 106         static char buf[HOSTLEN + HOSTLEN + PORTNAMELEN + 4];
 107         int port = 0;
 108
 109         s_assert(NULL != listener);
 110         if(listener == NULL)
 111                 return NULL;
 112
 113 #ifdef IPV6
 114         if(listener->addr.ss_family == AF_INET6)
 115                 port = ntohs(((const struct sockaddr_in6 *)&listener->addr)->sin6_port);
 116         else
 117 #endif
 118                 port = ntohs(((const struct sockaddr_in *)&listener->addr)->sin_port);
 119
 120         rb_snprintf(buf, sizeof(buf), "%s[%s/%u]", me.name, listener->name, port);
 121         return buf;
 122 }
 123
 124 /*
 125  * show_ports - send port listing to a client
 126  * inputs       - pointer to client to show ports to
 127  * output       - none
 128  * side effects - show ports
 129  */
 130 void
 131 show_ports(struct Client *source_p)
 132 {
 133         listener_t *listener = 0;
 134
 135         for (listener = ListenerPollList; listener; listener = listener->next)
 136         {
 137                 sendto_one_numeric(source_p, RPL_STATSPLINE,
 138                                    form_str(RPL_STATSPLINE), 'P',
 139 #ifdef IPV6
 140                            ntohs(listener->addr.ss_family == AF_INET ? ((struct sockaddr_in *)&listener->addr)->sin_port :
 141                                  ((struct sockaddr_in6 *)&listener->addr)->sin6_port),
 142 #else
 143                            ntohs(((struct sockaddr_in *)&listener->addr)->sin_port),
 144 #endif
 145                            IsOperAdmin(source_p) ? listener->name : me.name,
 146                            listener->ref_count, (listener->active) ? "active" : "disabled");
 147         }
 148 }
 149
 150 /*
 151  * inetport - create a listener socket in the AF_INET or AF_INET6 domain,
 152  * bind it to the port given in 'port' and listen to it
 153  * returns true (1) if successful false (0) on error.
 154  *
 155  * If the operating system has a define for SOMAXCONN, use it, otherwise
 156  * use RATBOX_SOMAXCONN
 157  */
 158 #ifdef SOMAXCONN
 159 #undef RATBOX_SOMAXCONN
 160 #define RATBOX_SOMAXCONN SOMAXCONN
 161 #endif
 162
 163 static int
 164 inetport(listener_t *listener)
 165 {
 166         rb_fde_t *F;
 167         int opt = 1;
 168
 169         /*
 170          * At first, open a new socket
 171          */
 172
 173         F = rb_socket(GET_SS_FAMILY(&listener->addr), SOCK_STREAM, 0, "Listener socket");
 174
 175 #ifdef IPV6
 176         if(listener->addr.ss_family == AF_INET6)
 177         {
 178                 struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)&listener->addr;
 179                 if(!IN6_ARE_ADDR_EQUAL(&in6->sin6_addr, &in6addr_any))
 180                 {
 181                         inetntop(AF_INET6, &in6->sin6_addr, listener->vhost, sizeof(listener->vhost));
 182                         listener->name = listener->vhost;
 183                 }
 184         } else
 185 #endif
 186         {
 187                 struct sockaddr_in *in = (struct sockaddr_in *)&listener->addr;
 188                 if(in->sin_addr.s_addr != INADDR_ANY)
 189                 {
 190                         inetntop(AF_INET, &in->sin_addr, listener->vhost, sizeof(listener->vhost));
 191                         listener->name = listener->vhost;
 192                 }
 193         }
 194
 195         if(F == NULL)
 196         {
 197                 report_error("opening listener socket %s:%s",
 198                              get_listener_name(listener),
 199                              get_listener_name(listener), errno);
 200                 return 0;
 201         }
 202         else if((maxconnections - 10) < rb_get_fd(F)) /* XXX this is kinda bogus*/
 203         {
 204                 report_error("no more connections left for listener %s:%s",
 205                              get_listener_name(listener),
 206                              get_listener_name(listener), errno);
 207                 rb_close(F);
 208                 return 0;
 209         }
 210
 211         /*
 212          * XXX - we don't want to do all this crap for a listener
 213          * set_sock_opts(listener);
 214          */
 215         if(setsockopt(rb_get_fd(F), SOL_SOCKET, SO_REUSEADDR, (char *) &opt, sizeof(opt)))
 216         {
 217                 report_error("setting SO_REUSEADDR for listener %s:%s",
 218                              get_listener_name(listener),
 219                              get_listener_name(listener), errno);
 220                 rb_close(F);
 221                 return 0;
 222         }
 223
 224         /*
 225          * Bind a port to listen for new connections if port is non-null,
 226          * else assume it is already open and try get something from it.
 227          */
 228
 229         if(bind(rb_get_fd(F), (struct sockaddr *) &listener->addr, GET_SS_LEN(&listener->addr)))
 230         {
 231                 report_error("binding listener socket %s:%s",
 232                              get_listener_name(listener),
 233                              get_listener_name(listener), errno);
 234                 rb_close(F);
 235                 return 0;
 236         }
 237
 238         if((ret = rb_listen(F, RATBOX_SOMAXCONN)))
 239         {
 240                 report_error("listen failed for %s:%s",
 241                              get_listener_name(listener),
 242                              get_listener_name(listener), errno);
 243                 rb_close(F);
 244                 return 0;
 245         }
 246
 247         listener->F = F;
 248
 249         rb_accept_tcp(listener->F, accept_precallback, accept_callback, listener);
 250         return 1;
 251 }
 252
 253 static listener_t *
 254 find_listener(struct rb_sockaddr_storage *addr)
 255 {
 256         listener_t *listener = NULL;
 257         listener_t *last_closed = NULL;
 258
 259         for (listener = ListenerPollList; listener; listener = listener->next)
 260         {
 261                 if(addr->ss_family != listener->addr.ss_family)
 262                         continue;
 263
 264                 switch(addr->ss_family)
 265                 {
 266                         case AF_INET:
 267                         {
 268                                 struct sockaddr_in *in4 = (struct sockaddr_in *)addr;
 269                                 struct sockaddr_in *lin4 = (struct sockaddr_in *)&listener->addr;
 270                                 if(in4->sin_addr.s_addr == lin4->sin_addr.s_addr &&
 271                                         in4->sin_port == lin4->sin_port )
 272                                 {
 273                                         if(listener->F == NULL)
 274                                                 last_closed = listener;
 275                                         else
 276                                                 return(listener);
 277                                 }
 278                                 break;
 279                         }
 280 #ifdef IPV6
 281                         case AF_INET6:
 282                         {
 283                                 struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)addr;
 284                                 struct sockaddr_in6 *lin6 =(struct sockaddr_in6 *)&listener->addr;
 285                                 if(IN6_ARE_ADDR_EQUAL(&in6->sin6_addr, &lin6->sin6_addr) &&
 286                                   in6->sin6_port == lin6->sin6_port)
 287                                 {
 288                                         if(listener->F == NULL)
 289                                                 last_closed = listener;
 290                                         else
 291                                                 return(listener);
 292                                 }
 293                                 break;
 294
 295                         }
 296 #endif
 297
 298                         default:
 299                                 break;
 300                 }
 301         }
 302         return last_closed;
 303 }
 304
 305
 306 /*
 307  * add_listener- create a new listener
 308  * port - the port number to listen on
 309  * vhost_ip - if non-null must contain a valid IP address string in
 310  * the format "255.255.255.255"
 311  */
 312 void
 313 add_listener(int port, const char *vhost_ip, int family)
 314 {
 315         listener_t *listener;
 316         struct rb_sockaddr_storage vaddr;
 317
 318         /*
 319          * if no port in conf line, don't bother
 320          */
 321         if(port == 0)
 322                 return;
 323         memset(&vaddr, 0, sizeof(vaddr));
 324         vaddr.ss_family = family;
 325
 326         if(vhost_ip != NULL)
 327         {
 328                 if(family == AF_INET)
 329                 {
 330                         if(inetpton(family, vhost_ip, &((struct sockaddr_in *)&vaddr)->sin_addr) <= 0)
 331                                 return;
 332                 }
 333 #ifdef IPV6
 334                 else
 335                 {
 336                         if(inetpton(family, vhost_ip, &((struct sockaddr_in6 *)&vaddr)->sin6_addr) <= 0)
 337                                 return;
 338
 339                 }
 340 #endif
 341         } else
 342         {
 343                 switch(family)
 344                 {
 345                         case AF_INET:
 346                                 ((struct sockaddr_in *)&vaddr)->sin_addr.s_addr = INADDR_ANY;
 347                                 break;
 348 #ifdef IPV6
 349                         case AF_INET6:
 350                                 memcpy(&((struct sockaddr_in6 *)&vaddr)->sin6_addr, &in6addr_any, sizeof(struct in6_addr));
 351                                 break;
 352                         default:
 353                                 return;
 354 #endif
 355                 }
 356         }
 357         switch(family)
 358         {
 359                 case AF_INET:
 360                         SET_SS_LEN(vaddr, sizeof(struct sockaddr_in));
 361                         ((struct sockaddr_in *)&vaddr)->sin_port = htons(port);
 362                         break;
 363 #ifdef IPV6
 364                 case AF_INET6:
 365                         SET_SS_LEN(vaddr, sizeof(struct sockaddr_in6));
 366                         ((struct sockaddr_in6 *)&vaddr)->sin6_port = htons(port);
 367                         break;
 368 #endif
 369                 default:
 370                         break;
 371         }
 372         if((listener = find_listener(&vaddr)))
 373         {
 374                 if(listener->F != NULL)
 375                         return;
 376         }
 377         else
 378         {
 379                 listener = make_listener(&vaddr);
 380                 listener->next = ListenerPollList;
 381                 ListenerPollList = listener;
 382         }
 383
 384         listener->F = NULL;
 385
 386         if(inetport(listener))
 387                 listener->active = 1;
 388         else
 389                 close_listener(listener);
 390 }
 391
 392 /*
 393  * close_listener - close a single listener
 394  */
 395 void
 396 close_listener(listener_t *listener)
 397 {
 398         s_assert(listener != NULL);
 399         if(listener == NULL)
 400                 return;
 401         if(listener->F != NULL)
 402         {
 403                 rb_close(listener->F);
 404                 listener->F = NULL;
 405         }
 406
 407         listener->active = 0;
 408
 409         if(listener->ref_count)
 410                 return;
 411
 412         free_listener(listener);
 413 }
 414
 415 /*
 416  * close_listeners - close and free all listeners that are not being used
 417  */
 418 void
 419 close_listeners()
 420 {
 421         listener_t *listener;
 422         listener_t *listener_next = 0;
 423         /*
 424          * close all 'extra' listening ports we have
 425          */
 426         for (listener = ListenerPollList; listener; listener = listener_next)
 427         {
 428                 listener_next = listener->next;
 429                 close_listener(listener);
 430         }
 431 }
 432
 433 #define DLINE_WARNING "ERROR :You have been D-lined.\r\n"
 434
 435 /*
 436  * add_connection - creates a client which has just connected to us on
 437  * the given fd. The sockhost field is initialized with the ip# of the host.
 438  * The client is sent to the auth module for verification, and not put in
 439  * any client list yet.
 440  */
 441 static void
 442 add_connection(listener_t *listener, int fd, struct sockaddr *sai, int exempt)
 443 {
 444         struct Client *new_client;
 445         s_assert(NULL != listener);
 446
 447         /*
 448          * get the client socket name from the socket
 449          * the client has already been checked out in accept_connection
 450          */
 451         new_client = make_client(NULL);
 452
 453         memcpy(&new_client->localClient->ip, sai, sizeof(struct rb_sockaddr_storage));
 454
 455         /*
 456          * copy address to 'sockhost' as a string, copy it to host too
 457          * so we have something valid to put into error messages...
 458          */
 459         inetntop_sock((struct sockaddr *)&new_client->localClient->ip, new_client->sockhost,
 460                 sizeof(new_client->sockhost));
 461
 462
 463         strlcpy(new_client->host, new_client->sockhost, sizeof(new_client->host));
 464
 465         new_client->localClient->F = rb_add_fd(fd);
 466
 467         new_client->localClient->listener = listener;
 468         ++listener->ref_count;
 469
 470         if(!exempt)
 471         {
 472                 if(check_reject(new_client))
 473                         return;
 474                 if(add_unknown_ip(new_client))
 475                         return;
 476         }
 477
 478         start_auth(new_client);
 479 }