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 /** Track time (seconds) of last ICMP Port Unreachable error */
45 time_t last_unreachable;
46 /** Common sender client data */
47 struct sender_client *sc;
48 /** The opaque structure returned by vss_add_fec_client(). */
49 struct fec_client *fc;
50 /** The FEC parameters for this target. */
51 struct fec_client_parms fcp;
54 static struct list_head targets;
55 static int sender_status;
57 static void udp_close_target(struct sender_client *sc)
60 del_close_on_fork_list(sc->fd);
66 static void udp_delete_target(struct udp_target *ut, const char *msg)
68 PARA_NOTICE_LOG("deleting %s (%s) from list\n", ut->sc->name, msg);
69 udp_close_target(ut->sc);
70 vss_del_fec_client(ut->fc);
71 list_del(&ut->sc->node);
78 * Perform AF-independent multicast sender setup.
80 * \param sc The connected sender client.
82 * \return Zero if okay, negative on error.
84 static int mcast_sender_setup(struct sender_client *sc)
86 struct sockaddr_storage ss;
87 socklen_t sslen = sizeof(ss);
88 int ttl = conf.udp_ttl_arg, id = 0;
91 if (conf.udp_mcast_iface_given) {
92 char *iface = conf.udp_mcast_iface_arg;
94 id = if_nametoindex(iface);
96 PARA_WARNING_LOG("could not resolve interface '%s', "
97 "using default", iface);
100 if (getpeername(sc->fd, (struct sockaddr *)&ss, &sslen) < 0)
103 /* RFC 3493, 5.2: -1 means 'use kernel default' */
104 if (ttl < 0 || ttl > 255)
107 switch (ss.ss_family) {
109 if (!IN_MULTICAST(htonl(((struct sockaddr_in *)&ss)->sin_addr.s_addr)))
115 memset(&mn, 0, sizeof(mn));
117 if (setsockopt(sc->fd, IPPROTO_IP, IP_MULTICAST_IF, &mn, sizeof(mn)) < 0)
120 PARA_ERROR_LOG("No support for setting outgoing IPv4 mcast interface.");
124 * Enable receiving multicast messages generated on the local host
125 * At least on Linux, this is enabled by default.
127 if (setsockopt(sc->fd, IPPROTO_IP, IP_MULTICAST_LOOP, &on, sizeof(on)) < 0)
130 /* Default: use local subnet (do not flood out into the WAN) */
133 if (setsockopt(sc->fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)) < 0)
137 if (!IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6 *)&ss)->sin6_addr))
140 setsockopt(sc->fd, IPPROTO_IPV6, IPV6_MULTICAST_IF, &id, sizeof(id)) < 0)
142 if (setsockopt(sc->fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &on, sizeof(on)) < 0)
144 if (setsockopt(sc->fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl)) < 0)
148 PARA_ERROR_LOG("address family %d not supported", ss.ss_family);
149 return -E_ADDRESS_LOOKUP;
152 return -ERRNO_TO_PARA_ERROR(errno);
155 /** The maximal size of the per-target chunk queue. */
156 #define UDP_CQ_BYTES 40000
158 static void udp_init_session(struct sender_client *sc)
160 if (sc->cq == NULL) {
161 sc->cq = cq_new(UDP_CQ_BYTES);
162 add_close_on_fork_list(sc->fd);
163 PARA_NOTICE_LOG("sending to udp %s\n", sc->name);
167 static void udp_shutdown_targets(void)
169 struct sender_client *sc, *tmp;
171 size_t len = vss_get_fec_eof_packet(&buf);
173 list_for_each_entry_safe(sc, tmp, &targets, node)
174 if (sc->cq != NULL) {
175 /* ignore return value, closing the target anyway. */
176 (void)write(sc->fd, buf, len);
177 udp_close_target(sc);
181 static int udp_resolve_target(const char *url, struct sender_command_data *scd)
186 ret = parse_fec_url(url, scd);
189 port = scd->port > 0 ? scd->port : conf.udp_default_port_arg;
191 ret = para_connect_simple(IPPROTO_UDP, scd->host, port);
195 result = remote_name(ret);
198 if (!parse_url(result, scd->host, sizeof(scd->host), &scd->port))
199 return -E_ADDRESS_LOOKUP;
203 static int udp_com_on(__a_unused struct sender_command_data *scd)
205 sender_status = SENDER_ON;
209 static int udp_com_off(__a_unused struct sender_command_data *scd)
211 udp_shutdown_targets();
212 sender_status = SENDER_OFF;
216 static int udp_com_delete(struct sender_command_data *scd)
218 struct sender_client *sc, *tmp;
219 char host[MAX_HOSTLEN];
222 list_for_each_entry_safe(sc, tmp, &targets, node) {
223 struct udp_target *ut = sc->private_data;
224 parse_url(sc->name, host, sizeof(host), &port);
226 /* Unspecified port means wildcard port match */
227 if (scd->port > 0 && scd->port != port)
229 if (strcmp(host, scd->host))
231 udp_delete_target(ut, "com_delete");
236 /** Initialize UDP session and set maximum payload size. */
237 static int udp_init_fec(struct sender_client *sc)
241 udp_init_session(sc);
242 mps = generic_max_transport_msg_size(sc->fd) - sizeof(struct udphdr);
243 PARA_INFO_LOG("current MPS = %d bytes\n", mps);
247 /** Check and clear socket error if any. */
248 static int udp_check_socket_state(struct udp_target *ut)
251 socklen_t errlen = sizeof(ret);
253 if (getsockopt(ut->sc->fd, SOL_SOCKET, SO_ERROR, &ret, &errlen) < 0) {
254 PARA_ERROR_LOG("SO_ERROR failed: %s\n", strerror(ret));
256 } else if (ret == 0) {
258 } else if (ret == ECONNREFUSED) {
259 time_t dist = now->tv_sec - ut->last_unreachable;
261 if (dist <= UDP_MAX_UNREACHABLE_TIME) {
263 } else if (dist > 2 * UDP_MAX_UNREACHABLE_TIME) {
264 ut->last_unreachable = now->tv_sec;
268 * unreachable_time < dist <= 2 * unreachable_time
269 * No errors are allowed during this time window.
271 PARA_NOTICE_LOG("Evicting %s after %d seconds "
272 "of connection errors.\n",
273 ut->sc->name, (int)dist);
276 return -ERRNO_TO_PARA_ERROR(ret);
279 static int udp_send_fec(struct sender_client *sc, char *buf, size_t len)
281 struct udp_target *ut = sc->private_data;
284 if (sender_status == SENDER_OFF)
286 if (len == 0 && !cq_peek(ut->sc->cq))
288 ret = udp_check_socket_state(ut);
291 ret = send_queued_chunks(sc->fd, sc->cq);
294 if (!ret) { /* still data left in the queue */
295 ret = cq_force_enqueue(sc->cq, buf, len);
299 ret = write_nonblock(sc->fd, buf, len);
300 if (ret == -ERRNO_TO_PARA_ERROR(ECONNREFUSED)) {
302 * Happens if meanwhile an ICMP Destination / Port Unreachable
303 * has arrived. Ignore, persistent errors will be caught above.
310 ret = cq_force_enqueue(sc->cq, buf + ret, len - ret);
315 udp_delete_target(ut, para_strerror(-ret));
319 static void udp_add_target(struct sender_command_data *scd)
322 struct udp_target *ut = para_calloc(sizeof(*ut));
324 ut->fcp.slices_per_group = scd->slices_per_group;
325 ut->fcp.data_slices_per_group = scd->data_slices_per_group;
326 ut->fcp.max_slice_bytes = scd->max_slice_bytes;
327 ut->fcp.init_fec = udp_init_fec;
328 ut->fcp.send_fec = udp_send_fec;
330 ut->sc = para_calloc(sizeof(*ut->sc));
331 ut->sc->private_data = ut;
333 ret = para_connect_simple(IPPROTO_UDP, scd->host, scd->port);
338 ret = mcast_sender_setup(ut->sc);
341 ret = mark_fd_nonblocking(ut->sc->fd);
344 ut->sc->name = para_strdup(remote_name(ut->sc->fd));
345 PARA_INFO_LOG("adding to target list (%s)\n", ut->sc->name);
346 ut->fc = vss_add_fec_client(ut->sc, &ut->fcp);
347 para_list_add(&ut->sc->node, &targets);
352 PARA_NOTICE_LOG("failed to set up %s:%d (%s)- not adding it\n",
353 scd->host, scd->port, para_strerror(-ret));
358 static int udp_com_add(struct sender_command_data *scd)
364 static char *udp_info(void)
366 struct sender_client *sc;
367 char *ret, *tgts = NULL;
369 list_for_each_entry(sc, &targets, node) {
370 struct udp_target *ut = sc->private_data;
371 char *tmp = make_message("%s%s/%u:%u:%u ", tgts ? : "",
373 ut->fcp.max_slice_bytes,
374 ut->fcp.data_slices_per_group,
375 ut->fcp.slices_per_group
385 (sender_status == SENDER_ON)? "on" : "off",
386 stringify_port(conf.udp_default_port_arg, "udp"),
387 tgts? tgts : "(none)"
393 static void udp_init_target_list(void)
395 struct sender_command_data scd;
398 INIT_LIST_HEAD(&targets);
399 for (i = 0; i < conf.udp_target_given; i++) {
400 if (udp_resolve_target(conf.udp_target_arg[i], &scd) < 0)
401 PARA_CRIT_LOG("not adding requested target '%s'\n",
402 conf.udp_target_arg[i]);
404 udp_add_target(&scd);
408 static char *udp_help(void)
412 "usage: {add|delete} host[:port][/packet_size:k:n]\n"
413 "examples: add 224.0.1.38:1500 (IPv4 multicast)\n"
414 " add 224.0.1.38:1500/1400:14:16\n"
415 " (likewise, using 1400 byte packets, with 14\n"
416 " data slices per 16 slice FEC group)\n"
417 " add 10.10.1.42 (using default port)\n"
418 " add [FF05::42]:1500 (IPv6 multicast)\n"
419 " add [::1] (IPv6 localhost/default port)\n"
420 " delete myhost.net (host with port wildcard)\n"
421 " delete [badc0de::1] (IPv6 with port wildcard)\n"
426 * The init function of para_server's udp sender.
428 * \param s Pointer to the udp sender struct.
430 * It initializes all function pointers of \a s and the list of udp targets.
432 void udp_send_init(struct sender *s)
434 INIT_LIST_HEAD(&targets);
438 s->pre_select = NULL;
439 s->post_select = NULL;
440 s->shutdown_clients = udp_shutdown_targets;
441 s->resolve_target = udp_resolve_target;
442 s->client_cmds[SENDER_ON] = udp_com_on;
443 s->client_cmds[SENDER_OFF] = udp_com_off;
444 s->client_cmds[SENDER_DENY] = NULL;
445 s->client_cmds[SENDER_ALLOW] = NULL;
446 s->client_cmds[SENDER_ADD] = udp_com_add;
447 s->client_cmds[SENDER_DELETE] = udp_com_delete;
448 sender_status = SENDER_OFF;
449 udp_init_target_list();
450 if (!conf.udp_no_autostart_given)
451 sender_status = SENDER_ON;
452 PARA_DEBUG_LOG("udp sender init complete\n");