1 /************************************************************************
2 * IRC - Internet Relay Chat, src/listener.c
3 * Copyright (C) 1999 Thomas Helvey <tomh@inxpress.net>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 1, or (at your option)
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 * @brief Implementation for handling listening sockets.
28 #include "ircd_alloc.h"
29 #include "ircd_events.h"
30 #include "ircd_features.h"
32 #include "ircd_osdep.h"
33 #include "ircd_reply.h"
34 #include "ircd_snprintf.h"
35 #include "ircd_string.h"
43 #include "sys.h" /* MAXCLIENTS */
45 /* #include <assert.h> -- Now using assert in ircd_log.h */
52 #include <sys/socket.h>
54 /** List of listening sockets. */
55 struct Listener* ListenerPollList = 0;
57 static void accept_connection(struct Event* ev);
59 /** Allocate and initialize a new Listener structure for a particular
61 * @param[in] port Port number to listen on.
62 * @param[in] addr Local address to listen on.
63 * @return Newly allocated and initialized Listener.
65 static struct Listener* make_listener(int port, const struct irc_in_addr *addr)
67 struct Listener* listener =
68 (struct Listener*) MyMalloc(sizeof(struct Listener));
69 assert(0 != listener);
71 memset(listener, 0, sizeof(struct Listener));
74 listener->addr.port = port;
75 memcpy(&listener->addr.addr, addr, sizeof(listener->addr.addr));
77 #ifdef NULL_POINTER_NOT_ZERO
78 listener->next = NULL;
79 listener->conf = NULL;
84 /** Deallocate a Listener structure.
85 * @param[in] listener Listener to be freed.
87 static void free_listener(struct Listener* listener)
89 assert(0 != listener);
93 /** Maximum length for a port number. */
94 #define PORTNAMELEN 10 /* ":31337" */
96 /** Return displayable listener name and port.
97 * @param[in] listener %Listener to format as a text string.
98 * @return Pointer to a static buffer that contains "server.name:6667".
100 const char* get_listener_name(const struct Listener* listener)
102 static char buf[HOSTLEN + PORTNAMELEN + 4];
103 assert(0 != listener);
104 ircd_snprintf(0, buf, sizeof(buf), "%s:%u", cli_name(&me), listener->addr.port);
108 /** Count allocated listeners and the memory they use.
109 * @param[out] count_out Receives number of allocated listeners.
110 * @param[out] size_out Receives bytes used by listeners.
112 void count_listener_memory(int* count_out, size_t* size_out)
116 assert(0 != count_out);
117 assert(0 != size_out);
118 for (l = ListenerPollList; l; l = l->next)
121 *size_out = count * sizeof(struct Listener);
124 /** Report listening ports to a client.
125 * @param[in] sptr Client requesting statistics.
126 * @param[in] sd Stats descriptor for request (ignored).
127 * @param[in] param Extra parameter from user (port number to search for).
129 void show_ports(struct Client* sptr, const struct StatDesc* sd,
132 struct Listener *listener = 0;
134 int show_hidden = IsOper(sptr);
135 int count = (IsOper(sptr) || MyUser(sptr)) ? 100 : 8;
144 for (listener = ListenerPollList; listener; listener = listener->next) {
145 if (port && port != listener->addr.port)
148 flags[len++] = listener_server(listener) ? 'S' : 'C';
149 if (show_hidden && FlagHas(&listener->flags, LISTEN_HIDDEN))
153 send_reply(sptr, RPL_STATSPLINE, listener->addr.port, listener->ref_count,
154 flags, listener_active(listener) ? "active" : "disabled");
161 * inetport - create a listener socket in the AF_INET domain,
162 * bind it to the port given in 'port' and listen to it
163 * returns true (1) if successful false (0) on error.
165 * If the operating system has a define for SOMAXCONN, use it, otherwise
166 * use HYBRID_SOMAXCONN -Dianora
167 * NOTE: Do this in os_xxxx.c files
170 #define HYBRID_SOMAXCONN SOMAXCONN
172 /** Maximum length of socket connection backlog. */
173 #define HYBRID_SOMAXCONN 64
176 /** Set or update socket options for \a listener.
177 * @param[in] listener Listener to determine socket option values.
178 * @param[in] fd File descriptor being updated.
179 * @return Non-zero on success, zero on failure.
181 static int set_listener_options(struct Listener *listener, int fd)
185 is_server = listener_server(listener);
187 * Set the buffer sizes for the listener. Accepted connections
188 * inherit the accepting sockets settings for SO_RCVBUF S_SNDBUF
189 * The window size is set during the SYN ACK so setting it anywhere
190 * else has no effect whatsoever on the connection.
191 * NOTE: this must be set before listen is called
193 if (!os_set_sockbufs(fd,
194 is_server ? feature_int(FEAT_SOCKSENDBUF) : CLIENT_TCP_WINDOW,
195 is_server ? feature_int(FEAT_SOCKRECVBUF) : CLIENT_TCP_WINDOW)) {
196 report_error(SETBUFS_ERROR_MSG, get_listener_name(listener), errno);
202 * Set the TOS bits - this is nonfatal if it doesn't stick.
204 if (!os_set_tos(fd,feature_int(is_server ? FEAT_TOS_SERVER : FEAT_TOS_CLIENT))) {
205 report_error(TOS_ERROR_MSG, get_listener_name(listener), errno);
211 /** Open listening socket for \a listener.
212 * @param[in,out] listener Listener to make a socket for.
213 * @return Non-zero on success, zero on failure.
215 static int inetport(struct Listener* listener)
220 * At first, open a new socket
222 fd = os_socket(&listener->addr, SOCK_STREAM, get_listener_name(listener), 0);
225 if (!os_set_listen(fd, HYBRID_SOMAXCONN)) {
226 report_error(LISTEN_ERROR_MSG, get_listener_name(listener), errno);
230 if (!set_listener_options(listener, fd))
232 if (!socket_add(&listener->socket, accept_connection, (void*) listener,
233 SS_LISTENING, 0, fd)) {
234 /* Error should already have been reported to the logs */
244 /** Find the listener (if any) for a particular port and address.
245 * @param[in] port Port number to search for.
246 * @param[in] addr Local address to search for.
247 * @return Listener that matches (or NULL if none match).
249 static struct Listener* find_listener(int port, const struct irc_in_addr *addr)
251 struct Listener* listener;
252 for (listener = ListenerPollList; listener; listener = listener->next) {
253 if (port == listener->addr.port && !memcmp(addr, &listener->addr.addr, sizeof(*addr)))
259 /** Make sure we have a listener for \a port on \a vhost_ip.
260 * If one does not exist, create it. Then mark it as active and set
261 * the peer mask, server, and hidden flags according to the other
263 * @param[in] port Port number to listen on.
264 * @param[in] vhost_ip Local address to listen on.
265 * @param[in] mask Address mask to accept connections from.
266 * @param[in] flags Flags describing listener options.
268 void add_listener(int port, const char* vhost_ip, const char* mask,
269 const struct ListenerFlags *flags)
271 struct Listener* listener;
272 struct irc_in_addr vaddr;
275 * if no port in conf line, don't bother
280 memset(&vaddr, 0, sizeof(vaddr));
282 if (!EmptyString(vhost_ip)
283 && strcmp(vhost_ip, "*")
284 && !ircd_aton(&vaddr, vhost_ip))
287 listener = find_listener(port, &vaddr);
289 listener = make_listener(port, &vaddr);
290 memcpy(&listener->flags, flags, sizeof(listener->flags));
291 FlagSet(&listener->flags, LISTEN_ACTIVE);
293 ipmask_parse(mask, &listener->mask, &listener->mask_bits);
295 listener->mask_bits = 0;
297 if (listener->fd >= 0) {
298 /* If the listener is already open, do not try to re-open.
299 * Only update the socket options.
301 set_listener_options(listener, listener->fd);
303 else if (inetport(listener)) {
304 listener->next = ListenerPollList;
305 ListenerPollList = listener;
308 free_listener(listener);
311 /** Mark all listeners as closing (inactive).
312 * This is done so unused listeners are closed after a rehash.
314 void mark_listeners_closing(void)
316 struct Listener* listener;
317 for (listener = ListenerPollList; listener; listener = listener->next)
318 FlagClr(&listener->flags, LISTEN_ACTIVE);
321 /** Close a single listener.
322 * @param[in] listener Listener to close.
324 void close_listener(struct Listener* listener)
326 assert(0 != listener);
328 * remove from listener list
330 if (listener == ListenerPollList)
331 ListenerPollList = listener->next;
333 struct Listener* prev = ListenerPollList;
334 for ( ; prev; prev = prev->next) {
335 if (listener == prev->next) {
336 prev->next = listener->next;
341 if (-1 < listener->fd)
343 socket_del(&listener->socket);
346 /** Close all inactive listeners. */
347 void close_listeners(void)
349 struct Listener* listener;
350 struct Listener* listener_next = 0;
352 * close all 'extra' listening ports we have
354 for (listener = ListenerPollList; listener; listener = listener_next) {
355 listener_next = listener->next;
356 if (!listener_active(listener) && 0 == listener->ref_count)
357 close_listener(listener);
361 /** Dereference the listener previously associated with a client.
362 * @param[in] listener Listener to dereference.
364 void release_listener(struct Listener* listener)
366 assert(0 != listener);
367 assert(0 < listener->ref_count);
368 if (0 == --listener->ref_count && !listener_active(listener))
369 close_listener(listener);
372 /** Accept a connection on a listener.
373 * @param[in] ev Socket callback structure.
375 static void accept_connection(struct Event* ev)
377 struct Listener* listener;
378 struct irc_sockaddr addr;
381 assert(0 != ev_socket(ev));
382 assert(0 != s_data(ev_socket(ev)));
384 listener = (struct Listener*) s_data(ev_socket(ev));
386 if (ev_type(ev) == ET_DESTROY) /* being destroyed */
387 free_listener(listener);
389 assert(ev_type(ev) == ET_ACCEPT || ev_type(ev) == ET_ERROR);
391 listener->last_accept = CurrentTime;
393 * There may be many reasons for error return, but
394 * in otherwise correctly working environment the
395 * probable cause is running out of file descriptors
396 * (EMFILE, ENFILE or others?). The man pages for
397 * accept don't seem to list these as possible,
398 * although it's obvious that it may happen here.
399 * Thus no specific errors are tested at this
400 * point, just assume that connections cannot
401 * be accepted until some old is closed first.
403 * This piece of code implements multi-accept, based
404 * on the idea that poll/select can only be efficient,
405 * if we succeed in handling all available events,
406 * i.e. accept all pending connections.
408 * http://www.hpl.hp.com/techreports/2000/HPL-2000-174.html
412 if ((fd = os_accept(listener->fd, &addr)) == -1)
414 if (errno == EAGAIN ||
416 errno == EWOULDBLOCK)
419 /* Lotsa admins seem to have problems with not giving enough file
420 * descriptors to their server so we'll add a generic warning mechanism
421 * here. If it turns out too many messages are generated for
422 * meaningless reasons we can filter them back.
424 sendto_opmask_butone(0, SNO_TCPCOMMON,
425 "Unable to accept connection: %m");
429 * check for connection limit. If this fd exceeds the limit,
430 * all further accept()ed connections will also exceed it.
431 * Enable the server to clear out other connections before
432 * continuing to accept() new connections.
434 if (fd > MAXCLIENTS - 1)
436 ++ServerStats->is_ref;
437 send(fd, "ERROR :All connections in use\r\n", 32, 0);
442 * check to see if listener is shutting down. Continue
443 * to accept(), because it makes sense to clear our the
444 * socket's queue as fast as possible.
446 if (!listener_active(listener))
448 ++ServerStats->is_ref;
449 send(fd, "ERROR :Use another port\r\n", 25, 0);
454 * check to see if connection is allowed for this address mask
456 if (!ipmask_check(&addr.addr, &listener->mask, listener->mask_bits))
458 ++ServerStats->is_ref;
459 send(fd, "ERROR :Use another port\r\n", 25, 0);
463 ++ServerStats->is_ac;
464 /* nextping = CurrentTime; */
465 add_connection(listener, fd);