2 * Copyright (C) 2005-2010 Andre Noll <maan@systemlinux.org>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file udp_send.c Para_server's udp sender. */
13 #include <sys/socket.h>
14 #include <netinet/udp.h>
18 #include "server.cmdline.h"
28 #include "portable_io.h"
32 #include "close_on_fork.h"
33 #include "chunk_queue.h"
36 * Time window during which ICMP Destination/Port Unreachable messages are
37 * ignored, covering transient receiver problems such as restarting the
38 * client, rebooting, reconfiguration, or handover.
40 #define UDP_MAX_UNREACHABLE_TIME 30
42 /** Describes one entry in the list of targets for the udp sender. */
44 /** The hostname (DNS name or IPv4/v6 address string). */
45 char host[MAX_HOSTLEN];
48 /** Track time (seconds) of last ICMP Port Unreachable error */
49 time_t last_unreachable;
50 /** Common sender client data */
51 struct sender_client *sc;
52 /** The opaque structure returned by vss_add_fec_client(). */
53 struct fec_client *fc;
54 /** The FEC parameters for this target. */
55 struct fec_client_parms fcp;
58 static struct list_head targets;
59 static int sender_status;
61 static void udp_close_target(struct sender_client *sc)
64 del_close_on_fork_list(sc->fd);
73 static void udp_delete_target(struct udp_target *ut, const char *msg)
76 PARA_NOTICE_LOG("deleting %s#%d (%s) from list\n", ut->host,
78 udp_close_target(ut->sc);
79 vss_del_fec_client(ut->fc);
80 list_del(&ut->sc->node);
86 * Perform AF-independent multicast sender setup.
88 * \param sc The connected sender client.
90 * \return Zero if okay, negative on error.
92 static int mcast_sender_setup(struct sender_client *sc)
94 struct sockaddr_storage ss;
95 socklen_t sslen = sizeof(ss);
96 int ttl = conf.udp_ttl_arg, id = 0;
99 if (conf.udp_mcast_iface_given) {
100 char *iface = conf.udp_mcast_iface_arg;
102 id = if_nametoindex(iface);
104 PARA_WARNING_LOG("could not resolve interface '%s', "
105 "using default", iface);
108 if (getpeername(sc->fd, (struct sockaddr *)&ss, &sslen) < 0)
111 /* RFC 3493, 5.2: -1 means 'use kernel default' */
112 if (ttl < 0 || ttl > 255)
115 switch (ss.ss_family) {
117 if (!IN_MULTICAST(htonl(((struct sockaddr_in *)&ss)->sin_addr.s_addr)))
123 memset(&mn, 0, sizeof(mn));
125 if (setsockopt(sc->fd, IPPROTO_IP, IP_MULTICAST_IF, &mn, sizeof(mn)) < 0)
128 PARA_ERROR_LOG("No support for setting outgoing IPv4 mcast interface.");
132 * Enable receiving multicast messages generated on the local host
133 * At least on Linux, this is enabled by default.
135 if (setsockopt(sc->fd, IPPROTO_IP, IP_MULTICAST_LOOP, &on, sizeof(on)) < 0)
138 /* Default: use local subnet (do not flood out into the WAN) */
141 if (setsockopt(sc->fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)) < 0)
145 if (!IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6 *)&ss)->sin6_addr))
148 setsockopt(sc->fd, IPPROTO_IPV6, IPV6_MULTICAST_IF, &id, sizeof(id)) < 0)
150 if (setsockopt(sc->fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &on, sizeof(on)) < 0)
152 if (setsockopt(sc->fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl)) < 0)
156 PARA_ERROR_LOG("address family %d not supported", ss.ss_family);
157 return -E_ADDRESS_LOOKUP;
160 return -ERRNO_TO_PARA_ERROR(errno);
163 /** The maximal size of the per-target chunk queue. */
164 #define UDP_CQ_BYTES 40000
166 static void udp_init_session(struct sender_client *sc)
168 if (sc->cq == NULL) {
169 add_close_on_fork_list(sc->fd);
170 sc->cq = cq_new(UDP_CQ_BYTES);
171 sc->name = para_strdup(remote_name(sc->fd));
172 PARA_NOTICE_LOG("sending to udp %s\n", sc->name);
176 static void udp_shutdown_targets(void)
178 struct sender_client *sc, *tmp;
180 size_t len = vss_get_fec_eof_packet(&buf);
182 list_for_each_entry_safe(sc, tmp, &targets, node)
183 if (sc->cq != NULL) {
184 /* ignore return value, closing the target anyway. */
185 (void)write(sc->fd, buf, len);
186 udp_close_target(sc);
190 static int udp_com_on(__a_unused struct sender_command_data *scd)
192 sender_status = SENDER_ON;
196 static int udp_com_off(__a_unused struct sender_command_data *scd)
198 udp_shutdown_targets();
199 sender_status = SENDER_OFF;
203 static int udp_com_delete(struct sender_command_data *scd)
205 struct sender_client *sc, *tmp;
207 list_for_each_entry_safe(sc, tmp, &targets, node) {
208 struct udp_target *ut = sc->private_data;
210 /* Unspecified port means wildcard port match */
211 if (scd->port > 0 && scd->port != ut->port)
213 if (strcmp(ut->host, scd->host))
215 udp_delete_target(ut, "com_delete");
220 /** Initialize UDP session and set maximum payload size. */
221 static int udp_init_fec(struct sender_client *sc)
225 udp_init_session(sc);
226 mps = generic_max_transport_msg_size(sc->fd) - sizeof(struct udphdr);
227 PARA_INFO_LOG("current MPS = %d bytes\n", mps);
231 /** Check and clear socket error if any. */
232 static int udp_check_socket_state(struct udp_target *ut)
235 socklen_t errlen = sizeof(ret);
237 if (getsockopt(ut->sc->fd, SOL_SOCKET, SO_ERROR, &ret, &errlen) < 0) {
238 PARA_ERROR_LOG("SO_ERROR failed: %s\n", strerror(ret));
240 } else if (ret == 0) {
242 } else if (ret == ECONNREFUSED) {
243 time_t dist = now->tv_sec - ut->last_unreachable;
245 if (dist <= UDP_MAX_UNREACHABLE_TIME) {
247 } else if (dist > 2 * UDP_MAX_UNREACHABLE_TIME) {
248 ut->last_unreachable = now->tv_sec;
252 * unreachable_time < dist <= 2 * unreachable_time
253 * No errors are allowed during this time window.
255 PARA_NOTICE_LOG("Evicting %s#%d after %d seconds "
256 "of connection errors.\n",
257 ut->host, ut->port, (int)dist);
260 return -ERRNO_TO_PARA_ERROR(ret);
263 static int udp_send_fec(struct sender_client *sc, char *buf, size_t len)
265 struct udp_target *ut = sc->private_data;
268 if (sender_status == SENDER_OFF)
270 if (len == 0 && !cq_peek(ut->sc->cq))
272 ret = udp_check_socket_state(ut);
275 ret = send_queued_chunks(sc->fd, sc->cq);
278 if (!ret) { /* still data left in the queue */
279 ret = cq_force_enqueue(sc->cq, buf, len);
283 ret = write_nonblock(sc->fd, buf, len);
284 if (ret == -ERRNO_TO_PARA_ERROR(ECONNREFUSED)) {
286 * Happens if meanwhile an ICMP Destination / Port Unreachable
287 * has arrived. Ignore, persistent errors will be caught above.
294 ret = cq_force_enqueue(sc->cq, buf + ret, len - ret);
299 udp_delete_target(ut, para_strerror(-ret));
303 static void udp_add_target(struct sender_command_data *scd)
305 int ret, port = scd->port > 0 ? scd->port : conf.udp_default_port_arg;
306 struct udp_target *ut = para_calloc(sizeof(*ut));
308 strncpy(ut->host, scd->host, sizeof(ut->host));
309 ut->port = scd->port > 0 ? scd->port : conf.udp_default_port_arg;
311 ut->fcp.slices_per_group = scd->slices_per_group;
312 ut->fcp.data_slices_per_group = scd->data_slices_per_group;
313 ut->fcp.max_slice_bytes = scd->max_slice_bytes;
314 ut->fcp.init_fec = udp_init_fec;
315 ut->fcp.send_fec = udp_send_fec;
317 ut->sc = para_calloc(sizeof(*ut->sc));
318 ut->sc->private_data = ut;
320 ret = para_connect_simple(IPPROTO_UDP, scd->host, port);
325 ret = mcast_sender_setup(ut->sc);
328 ret = mark_fd_nonblocking(ut->sc->fd);
331 PARA_INFO_LOG("adding to target list (%s#%d)\n", ut->host, ut->port);
332 ut->fc = vss_add_fec_client(ut->sc, &ut->fcp);
333 para_list_add(&ut->sc->node, &targets);
338 PARA_NOTICE_LOG("failed to set up %s#%d (%s)- not adding it\n",
339 scd->host, port, para_strerror(-ret));
344 static int udp_com_add(struct sender_command_data *scd)
350 static char *udp_info(void)
352 struct sender_client *sc;
353 char *ret, *tgts = NULL;
355 list_for_each_entry(sc, &targets, node) {
356 struct udp_target *ut = sc->private_data;
357 bool is_v6 = strchr(ut->host, ':') != NULL;
358 char *tmp = make_message("%s%s%s%s:%d/%u:%u:%u ", tgts ? : "",
359 is_v6 ? "[" : "", ut->host,
360 is_v6 ? "]" : "", ut->port,
361 ut->fcp.max_slice_bytes,
362 ut->fcp.data_slices_per_group,
363 ut->fcp.slices_per_group
373 (sender_status == SENDER_ON)? "on" : "off",
374 stringify_port(conf.udp_default_port_arg, "udp"),
375 tgts? tgts : "(none)"
381 static void udp_init_target_list(void)
383 struct sender_command_data scd;
386 INIT_LIST_HEAD(&targets);
387 for (i = 0; i < conf.udp_target_given; i++) {
388 if (parse_fec_url(conf.udp_target_arg[i], &scd) < 0) {
389 PARA_CRIT_LOG("syntax error for udp target option "
390 "#%d, ignoring\n", i);
393 udp_add_target(&scd);
397 static char *udp_help(void)
401 "usage: {add|delete} host[:port][/packet_size:k:n]\n"
402 "examples: add 224.0.1.38:1500 (IPv4 multicast)\n"
403 " add 224.0.1.38:1500/1400:14:16\n"
404 " (likewise, using 1400 byte packets, with 14\n"
405 " data slices per 16 slice FEC group)\n"
406 " add 10.10.1.42 (using default port)\n"
407 " add [FF05::42]:1500 (IPv6 multicast)\n"
408 " add [::1] (IPv6 localhost/default port)\n"
409 " delete myhost.net (host with port wildcard)\n"
410 " delete [badc0de::1] (IPv6 with port wildcard)\n"
415 * The init function of para_server's udp sender.
417 * \param s Pointer to the udp sender struct.
419 * It initializes all function pointers of \a s and the list of udp targets.
421 void udp_send_init(struct sender *s)
423 INIT_LIST_HEAD(&targets);
427 s->pre_select = NULL;
428 s->post_select = NULL;
429 s->shutdown_clients = udp_shutdown_targets;
430 s->client_cmds[SENDER_ON] = udp_com_on;
431 s->client_cmds[SENDER_OFF] = udp_com_off;
432 s->client_cmds[SENDER_DENY] = NULL;
433 s->client_cmds[SENDER_ALLOW] = NULL;
434 s->client_cmds[SENDER_ADD] = udp_com_add;
435 s->client_cmds[SENDER_DELETE] = udp_com_delete;
436 sender_status = SENDER_OFF;
437 udp_init_target_list();
438 if (!conf.udp_no_autostart_given)
439 sender_status = SENDER_ON;
440 PARA_DEBUG_LOG("udp sender init complete\n");