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));
75 listener->addr.port = port;
76 memcpy(&listener->addr.addr, addr, sizeof(listener->addr.addr));
78 #ifdef NULL_POINTER_NOT_ZERO
79 listener->next = NULL;
80 listener->conf = NULL;
85 /** Deallocate a Listener structure.
86 * @param[in] listener Listener to be freed.
88 static void free_listener(struct Listener* listener)
90 assert(0 != listener);
94 /** Maximum length for a port number. */
95 #define PORTNAMELEN 10 /* ":31337" */
97 /** Return displayable listener name and port.
98 * @param[in] listener %Listener to format as a text string.
99 * @return Pointer to a static buffer that contains "server.name:6667".
101 const char* get_listener_name(const struct Listener* listener)
103 static char buf[HOSTLEN + PORTNAMELEN + 4];
104 assert(0 != listener);
105 ircd_snprintf(0, buf, sizeof(buf), "%s:%u", cli_name(&me), listener->addr.port);
109 /** Count allocated listeners and the memory they use.
110 * @param[out] count_out Receives number of allocated listeners.
111 * @param[out] size_out Receives bytes used by listeners.
113 void count_listener_memory(int* count_out, size_t* size_out)
117 assert(0 != count_out);
118 assert(0 != size_out);
119 for (l = ListenerPollList; l; l = l->next)
122 *size_out = count * sizeof(struct Listener);
125 /** Report listening ports to a client.
126 * @param[in] sptr Client requesting statistics.
127 * @param[in] sd Stats descriptor for request (ignored).
128 * @param[in] param Extra parameter from user (port number to search for).
130 void show_ports(struct Client* sptr, const struct StatDesc* sd,
133 struct Listener *listener = 0;
135 int show_hidden = IsOper(sptr);
136 int count = (IsOper(sptr) || MyUser(sptr)) ? 100 : 8;
145 for (listener = ListenerPollList; listener; listener = listener->next) {
146 if (port && port != listener->addr.port)
149 flags[len++] = listener_server(listener) ? 'S' : 'C';
150 if (show_hidden && FlagHas(&listener->flags, LISTEN_HIDDEN))
154 send_reply(sptr, RPL_STATSPLINE, listener->addr.port, listener->ref_count,
155 flags, listener_active(listener) ? "active" : "disabled");
162 * inetport - create a listener socket in the AF_INET domain,
163 * bind it to the port given in 'port' and listen to it
164 * returns true (1) if successful false (0) on error.
166 * If the operating system has a define for SOMAXCONN, use it, otherwise
167 * use HYBRID_SOMAXCONN -Dianora
168 * NOTE: Do this in os_xxxx.c files
171 #define HYBRID_SOMAXCONN SOMAXCONN
173 /** Maximum length of socket connection backlog. */
174 #define HYBRID_SOMAXCONN 64
177 /** Set or update socket options for \a listener.
178 * @param[in] listener Listener to determine socket option values.
179 * @param[in] fd File descriptor being updated.
180 * @return Non-zero on success, zero on failure.
182 static int set_listener_options(struct Listener *listener, int fd)
186 is_server = listener_server(listener);
188 * Set the buffer sizes for the listener. Accepted connections
189 * inherit the accepting sockets settings for SO_RCVBUF S_SNDBUF
190 * The window size is set during the SYN ACK so setting it anywhere
191 * else has no effect whatsoever on the connection.
192 * NOTE: this must be set before listen is called
194 if (!os_set_sockbufs(fd,
195 is_server ? feature_int(FEAT_SOCKSENDBUF) : CLIENT_TCP_WINDOW,
196 is_server ? feature_int(FEAT_SOCKRECVBUF) : CLIENT_TCP_WINDOW)) {
197 report_error(SETBUFS_ERROR_MSG, get_listener_name(listener), errno);
203 * Set the TOS bits - this is nonfatal if it doesn't stick.
205 if (!os_set_tos(fd,feature_int(is_server ? FEAT_TOS_SERVER : FEAT_TOS_CLIENT))) {
206 report_error(TOS_ERROR_MSG, get_listener_name(listener), errno);
212 /** Open listening socket for \a listener.
213 * @param[in,out] listener Listener to make a socket for.
214 * @param[in] family Socket address family to use.
215 * @return Negative on failure, file descriptor on success.
217 static int inetport(struct Listener* listener, int family)
223 * At first, open a new socket
225 fd = os_socket(&listener->addr, SOCK_STREAM, get_listener_name(listener), family);
228 if (!os_set_listen(fd, HYBRID_SOMAXCONN)) {
229 report_error(LISTEN_ERROR_MSG, get_listener_name(listener), errno);
233 if (!set_listener_options(listener, fd))
235 sock = (family == AF_INET) ? &listener->socket_v4 : &listener->socket_v6;
236 if (!socket_add(sock, accept_connection, (void*) listener,
237 SS_LISTENING, 0, fd)) {
238 /* Error should already have been reported to the logs */
246 /** Find the listener (if any) for a particular port and address.
247 * @param[in] port Port number to search for.
248 * @param[in] addr Local address to search for.
249 * @return Listener that matches (or NULL if none match).
251 static struct Listener* find_listener(int port, const struct irc_in_addr *addr)
253 struct Listener* listener;
254 for (listener = ListenerPollList; listener; listener = listener->next) {
255 if (port == listener->addr.port && !memcmp(addr, &listener->addr.addr, sizeof(*addr)))
261 /** Make sure we have a listener for \a port on \a vhost_ip.
262 * If one does not exist, create it. Then mark it as active and set
263 * the peer mask, server, and hidden flags according to the other
265 * @param[in] port Port number to listen on.
266 * @param[in] vhost_ip Local address to listen on.
267 * @param[in] mask Address mask to accept connections from.
268 * @param[in] flags Flags describing listener options.
270 void add_listener(int port, const char* vhost_ip, const char* mask,
271 const struct ListenerFlags *flags)
273 struct Listener* listener;
274 struct irc_in_addr vaddr;
276 int new_listener = 0;
280 * if no port in conf line, don't bother
285 memset(&vaddr, 0, sizeof(vaddr));
287 if (!EmptyString(vhost_ip)
288 && strcmp(vhost_ip, "*")
289 && !ircd_aton(&vaddr, vhost_ip))
292 listener = find_listener(port, &vaddr);
296 listener = make_listener(port, &vaddr);
298 memcpy(&listener->flags, flags, sizeof(listener->flags));
299 FlagSet(&listener->flags, LISTEN_ACTIVE);
301 ipmask_parse(mask, &listener->mask, &listener->mask_bits);
303 listener->mask_bits = 0;
306 if (FlagHas(&listener->flags, LISTEN_IPV6)) {
307 if (listener->fd_v6 >= 0) {
308 set_listener_options(listener, listener->fd_v6);
310 } else if ((fd = inetport(listener, AF_INET6)) >= 0) {
311 listener->fd_v6 = fd;
314 } else if (-1 < listener->fd_v6) {
315 close(listener->fd_v6);
316 socket_del(&listener->socket_v6);
317 listener->fd_v6 = -1;
321 if (FlagHas(&listener->flags, LISTEN_IPV4)) {
322 if (listener->fd_v4 >= 0) {
323 set_listener_options(listener, listener->fd_v4);
325 } else if ((fd = inetport(listener, AF_INET)) >= 0) {
326 listener->fd_v4 = fd;
329 } else if (-1 < listener->fd_v4) {
330 close(listener->fd_v4);
331 socket_del(&listener->socket_v4);
332 listener->fd_v4 = -1;
336 free_listener(listener);
337 else if (new_listener) {
338 listener->next = ListenerPollList;
339 ListenerPollList = listener;
343 /** Mark all listeners as closing (inactive).
344 * This is done so unused listeners are closed after a rehash.
346 void mark_listeners_closing(void)
348 struct Listener* listener;
349 for (listener = ListenerPollList; listener; listener = listener->next)
350 FlagClr(&listener->flags, LISTEN_ACTIVE);
353 /** Close a single listener.
354 * @param[in] listener Listener to close.
356 void close_listener(struct Listener* listener)
358 assert(0 != listener);
360 * remove from listener list
362 if (listener == ListenerPollList)
363 ListenerPollList = listener->next;
365 struct Listener* prev = ListenerPollList;
366 for ( ; prev; prev = prev->next) {
367 if (listener == prev->next) {
368 prev->next = listener->next;
373 if (-1 < listener->fd_v4) {
374 close(listener->fd_v4);
375 socket_del(&listener->socket_v4);
376 listener->fd_v4 = -1;
378 if (-1 < listener->fd_v6) {
379 close(listener->fd_v6);
380 socket_del(&listener->socket_v6);
381 listener->fd_v6 = -1;
383 free_listener(listener);
386 /** Close all inactive listeners. */
387 void close_listeners(void)
389 struct Listener* listener;
390 struct Listener* listener_next = 0;
392 * close all 'extra' listening ports we have
394 for (listener = ListenerPollList; listener; listener = listener_next) {
395 listener_next = listener->next;
396 if (!listener_active(listener) && 0 == listener->ref_count)
397 close_listener(listener);
401 /** Dereference the listener previously associated with a client.
402 * @param[in] listener Listener to dereference.
404 void release_listener(struct Listener* listener)
406 assert(0 != listener);
407 assert(0 < listener->ref_count);
408 if (0 == --listener->ref_count && !listener_active(listener))
409 close_listener(listener);
412 /** Accept a connection on a listener.
413 * @param[in] ev Socket callback structure.
415 static void accept_connection(struct Event* ev)
417 struct Listener* listener;
418 struct irc_sockaddr addr;
421 assert(0 != ev_socket(ev));
422 assert(0 != s_data(ev_socket(ev)));
424 listener = (struct Listener*) s_data(ev_socket(ev));
426 if (ev_type(ev) == ET_DESTROY) /* being destroyed */
429 assert(ev_type(ev) == ET_ACCEPT || ev_type(ev) == ET_ERROR);
431 listener->last_accept = CurrentTime;
433 * There may be many reasons for error return, but
434 * in otherwise correctly working environment the
435 * probable cause is running out of file descriptors
436 * (EMFILE, ENFILE or others?). The man pages for
437 * accept don't seem to list these as possible,
438 * although it's obvious that it may happen here.
439 * Thus no specific errors are tested at this
440 * point, just assume that connections cannot
441 * be accepted until some old is closed first.
443 * This piece of code implements multi-accept, based
444 * on the idea that poll/select can only be efficient,
445 * if we succeed in handling all available events,
446 * i.e. accept all pending connections.
448 * http://www.hpl.hp.com/techreports/2000/HPL-2000-174.html
452 if ((fd = os_accept(s_fd(ev_socket(ev)), &addr)) == -1)
454 if (errno == EAGAIN ||
456 errno == EWOULDBLOCK)
459 /* Lotsa admins seem to have problems with not giving enough file
460 * descriptors to their server so we'll add a generic warning mechanism
461 * here. If it turns out too many messages are generated for
462 * meaningless reasons we can filter them back.
464 sendto_opmask_butone(0, SNO_TCPCOMMON,
465 "Unable to accept connection: %m");
469 * check for connection limit. If this fd exceeds the limit,
470 * all further accept()ed connections will also exceed it.
471 * Enable the server to clear out other connections before
472 * continuing to accept() new connections.
474 if (fd > MAXCLIENTS - 1)
476 ++ServerStats->is_ref;
477 send(fd, "ERROR :All connections in use\r\n", 32, 0);
482 * check to see if listener is shutting down. Continue
483 * to accept(), because it makes sense to clear our the
484 * socket's queue as fast as possible.
486 if (!listener_active(listener))
488 ++ServerStats->is_ref;
489 send(fd, "ERROR :Use another port\r\n", 25, 0);
494 * check to see if connection is allowed for this address mask
496 if (!ipmask_check(&addr.addr, &listener->mask, listener->mask_bits))
498 ++ServerStats->is_ref;
499 send(fd, "ERROR :Use another port\r\n", 25, 0);
503 ++ServerStats->is_ac;
504 /* nextping = CurrentTime; */
505 add_connection(listener, fd);