2 * Copyright (C) 2005-2014 Andre Noll <maan@tuebingen.mpg.de>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file udp_send.c Para_server's udp sender. */
9 #include <netinet/in.h>
10 #include <sys/socket.h>
12 #include <sys/types.h>
13 #include <sys/socket.h>
14 #include <netinet/udp.h>
16 #include <arpa/inet.h>
21 #include "server.cmdline.h"
32 #include "portable_io.h"
35 #include "close_on_fork.h"
38 * Time window during which ICMP Destination/Port Unreachable messages are
39 * ignored, covering transient receiver problems such as restarting the
40 * client, rebooting, reconfiguration, or handover.
42 #define UDP_MAX_UNREACHABLE_TIME 30
44 /** Describes one entry in the list of targets for the udp sender. */
46 /** Track time (seconds) of last ICMP Port Unreachable error */
47 time_t last_unreachable
;
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 size_t len
= vss_get_fec_eof_packet(&buf
);
63 * Ignore the return value of wirte() since we are closing the target
64 * anyway. The sole purpose of the "do_nothing" statement is to silence
67 if (write(sc
->fd
, buf
, len
))
71 static void udp_delete_target(struct sender_client
*sc
, const char *msg
)
73 struct udp_target
*ut
= sc
->private_data
;
75 PARA_NOTICE_LOG("deleting %s (%s) from list\n", sc
->name
, msg
);
78 del_close_on_fork_list(sc
->fd
);
79 vss_del_fec_client(ut
->fc
);
87 * Perform AF-independent multicast sender setup.
89 * \param sc The connected sender client.
91 * \return Zero if okay, negative on error.
93 static int mcast_sender_setup(struct sender_client
*sc
)
95 struct sockaddr_storage ss
;
96 socklen_t sslen
= sizeof(ss
);
97 int ttl
= conf
.udp_ttl_arg
, id
= 0;
100 if (conf
.udp_mcast_iface_given
) {
101 char *iface
= conf
.udp_mcast_iface_arg
;
103 id
= if_nametoindex(iface
);
105 PARA_WARNING_LOG("could not resolve interface '%s', "
106 "using default", iface
);
109 if (getpeername(sc
->fd
, (struct sockaddr
*)&ss
, &sslen
) < 0)
111 assert(ss
.ss_family
== AF_INET
|| ss
.ss_family
== AF_INET6
);
113 /* RFC 3493, 5.2: -1 means 'use kernel default' */
114 if (ttl
< 0 || ttl
> 255)
117 switch (ss
.ss_family
) {
119 if (!IN_MULTICAST(htonl(((struct sockaddr_in
*)&ss
)->sin_addr
.s_addr
)))
125 memset(&mn
, 0, sizeof(mn
));
127 if (setsockopt(sc
->fd
, IPPROTO_IP
, IP_MULTICAST_IF
, &mn
, sizeof(mn
)) < 0)
130 PARA_ERROR_LOG("No support for setting outgoing IPv4 mcast interface.");
134 * Enable receiving multicast messages generated on the local host
135 * At least on Linux, this is enabled by default.
137 if (setsockopt(sc
->fd
, IPPROTO_IP
, IP_MULTICAST_LOOP
, &on
, sizeof(on
)) < 0)
140 /* Default: use local subnet (do not flood out into the WAN) */
143 if (setsockopt(sc
->fd
, IPPROTO_IP
, IP_MULTICAST_TTL
, &ttl
, sizeof(ttl
)) < 0)
147 if (!IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6
*)&ss
)->sin6_addr
))
150 setsockopt(sc
->fd
, IPPROTO_IPV6
, IPV6_MULTICAST_IF
, &id
, sizeof(id
)) < 0)
152 if (setsockopt(sc
->fd
, IPPROTO_IPV6
, IPV6_MULTICAST_LOOP
, &on
, sizeof(on
)) < 0)
154 if (setsockopt(sc
->fd
, IPPROTO_IPV6
, IPV6_MULTICAST_HOPS
, &ttl
, sizeof(ttl
)) < 0)
159 return -ERRNO_TO_PARA_ERROR(errno
);
162 static void udp_init_session(struct sender_client
*sc
)
164 PARA_NOTICE_LOG("sending to udp %s\n", sc
->name
);
167 static void udp_shutdown_targets(void)
169 struct sender_client
*sc
, *tmp
;
170 list_for_each_entry_safe(sc
, tmp
, &targets
, node
)
171 udp_close_target(sc
);
174 static int udp_resolve_target(const char *url
, struct sender_command_data
*scd
)
179 ret
= parse_fec_url(url
, scd
);
182 port
= scd
->port
> 0 ? scd
->port
: conf
.udp_default_port_arg
;
184 ret
= para_connect_simple(IPPROTO_UDP
, scd
->host
, port
);
188 result
= remote_name(ret
);
191 if (!parse_url(result
, scd
->host
, sizeof(scd
->host
), &scd
->port
))
192 return -E_ADDRESS_LOOKUP
;
196 static int udp_com_on(__a_unused
struct sender_command_data
*scd
)
198 sender_status
= SENDER_ON
;
202 static int udp_com_off(__a_unused
struct sender_command_data
*scd
)
204 udp_shutdown_targets();
205 sender_status
= SENDER_OFF
;
209 static struct sender_client
*udp_lookup_target(struct sender_command_data
*scd
)
211 struct sender_client
*sc
, *tmp
;
212 char host
[MAX_HOSTLEN
];
215 list_for_each_entry_safe(sc
, tmp
, &targets
, node
) {
216 parse_url(sc
->name
, host
, sizeof(host
), &port
);
218 /* Unspecified port means wildcard port match */
219 if (scd
->port
> 0 && scd
->port
!= port
)
221 if (strcmp(host
, scd
->host
))
228 static int udp_com_delete(struct sender_command_data
*scd
)
230 struct sender_client
*sc
= udp_lookup_target(scd
);
233 udp_delete_target(sc
, "com_delete");
236 PARA_NOTICE_LOG("not deleting non-existing target '%s'\n", scd
->host
);
237 return -E_TARGET_NOT_FOUND
;
240 /** Initialize UDP session and set maximum payload size. */
241 static int udp_init_fec(struct sender_client
*sc
)
245 udp_init_session(sc
);
246 mps
= generic_max_transport_msg_size(sc
->fd
) - sizeof(struct udphdr
);
247 PARA_INFO_LOG("current MPS = %d bytes\n", mps
);
251 /** Check and clear socket error if any. */
252 static int udp_check_socket_state(struct sender_client
*sc
)
254 struct udp_target
*ut
= sc
->private_data
;
256 socklen_t errlen
= sizeof(ret
);
258 if (getsockopt(sc
->fd
, SOL_SOCKET
, SO_ERROR
, &ret
, &errlen
) < 0) {
259 PARA_ERROR_LOG("SO_ERROR failed: %s\n", strerror(ret
));
261 } else if (ret
== 0) {
263 } else if (ret
== ECONNREFUSED
) {
264 time_t dist
= now
->tv_sec
- ut
->last_unreachable
;
266 if (dist
<= UDP_MAX_UNREACHABLE_TIME
) {
268 } else if (dist
> 2 * UDP_MAX_UNREACHABLE_TIME
) {
269 ut
->last_unreachable
= now
->tv_sec
;
273 * unreachable_time < dist <= 2 * unreachable_time
274 * No errors are allowed during this time window.
276 PARA_NOTICE_LOG("Evicting %s after %d seconds "
277 "of connection errors.\n",
278 sc
->name
, (int)dist
);
281 return -ERRNO_TO_PARA_ERROR(ret
);
284 static void udp_send_fec(struct sender_client
*sc
, char *buf
, size_t len
)
288 if (sender_status
== SENDER_OFF
)
292 ret
= udp_check_socket_state(sc
);
295 ret
= xwrite(sc
->fd
, buf
, len
);
296 if (ret
== -ERRNO_TO_PARA_ERROR(ECONNREFUSED
)) {
298 * Happens if meanwhile an ICMP Destination / Port Unreachable
299 * has arrived. Ignore, persistent errors will be caught above.
307 udp_delete_target(sc
, para_strerror(-ret
));
310 static int udp_com_add(struct sender_command_data
*scd
)
313 struct udp_target
*ut
;
314 struct sender_client
*sc
= udp_lookup_target(scd
);
317 PARA_NOTICE_LOG("target %s already exists - not adding it\n",
319 return -E_TARGET_EXISTS
;
321 ut
= para_calloc(sizeof(*ut
));
322 sc
= para_calloc(sizeof(*sc
));
323 ut
->fcp
.slices_per_group
= scd
->slices_per_group
;
324 ut
->fcp
.data_slices_per_group
= scd
->data_slices_per_group
;
325 ut
->fcp
.init_fec
= udp_init_fec
;
326 ut
->fcp
.send_fec
= udp_send_fec
;
327 ut
->fcp
.need_periodic_header
= true;
329 sc
->private_data
= ut
;
331 ret
= para_connect_simple(IPPROTO_UDP
, scd
->host
, scd
->port
);
336 ret
= mcast_sender_setup(sc
);
339 ret
= mark_fd_nonblocking(sc
->fd
);
342 sc
->name
= para_strdup(remote_name(sc
->fd
));
343 PARA_INFO_LOG("adding to target list (%s)\n", sc
->name
);
344 ut
->fc
= vss_add_fec_client(sc
, &ut
->fcp
);
345 para_list_add(&sc
->node
, &targets
);
346 add_close_on_fork_list(sc
->fd
);
351 PARA_NOTICE_LOG("failed to set up %s:%d (%s)- not adding it\n",
352 scd
->host
, scd
->port
, para_strerror(-ret
));
358 static char *udp_info(void)
360 struct sender_client
*sc
;
361 char *ret
, *tgts
= NULL
;
363 list_for_each_entry(sc
, &targets
, node
) {
364 struct udp_target
*ut
= sc
->private_data
;
365 char *tmp
= make_message("%s%s/%u:%u ",
366 tgts
? : "", sc
->name
,
367 ut
->fcp
.data_slices_per_group
,
368 ut
->fcp
.slices_per_group
378 (sender_status
== SENDER_ON
)? "on" : "off",
379 stringify_port(conf
.udp_default_port_arg
, "udp"),
380 tgts
? tgts
: "(none)"
386 static void udp_init_target_list(void)
388 struct sender_command_data scd
;
391 INIT_LIST_HEAD(&targets
);
392 for (i
= 0; i
< conf
.udp_target_given
; i
++) {
393 if (udp_resolve_target(conf
.udp_target_arg
[i
], &scd
) < 0)
394 PARA_CRIT_LOG("not adding requested target '%s'\n",
395 conf
.udp_target_arg
[i
]);
401 static char *udp_help(void)
405 "usage: {add|delete} ip_address[:port][/[packet_size:]k:n]\n"
406 " - k is the number of data slices per FEC group\n"
407 " - n is the total number of slices in a FEC group\n"
408 " - packet_size reduces the slice size below path MTU\n\n"
409 "examples: add 224.0.1.38:1500 (IPv4 multicast)\n"
410 " add 224.0.1.38:8080/14:16 (explicit FEC)\n"
411 " add 10.10.1.42 (using default port)\n"
412 " add [FF05::42]:1500 (IPv6 multicast)\n"
413 " add [::1] (IPv6 localhost/default port)\n"
414 " delete myhost.net (host with port wildcard)\n"
415 " delete 10.1.2.3:456 (IPv4 with explicit port)\n"
416 " delete [badc0de::1] (IPv6 with port wildcard)\n"
421 * The init function of para_server's udp sender.
423 * \param s Pointer to the udp sender struct.
425 * It initializes all function pointers of \a s and the list of udp targets.
427 void udp_send_init(struct sender
*s
)
429 INIT_LIST_HEAD(&targets
);
433 s
->pre_select
= NULL
;
434 s
->post_select
= NULL
;
435 s
->shutdown_clients
= udp_shutdown_targets
;
436 s
->resolve_target
= udp_resolve_target
;
437 s
->client_cmds
[SENDER_ON
] = udp_com_on
;
438 s
->client_cmds
[SENDER_OFF
] = udp_com_off
;
439 s
->client_cmds
[SENDER_DENY
] = NULL
;
440 s
->client_cmds
[SENDER_ALLOW
] = NULL
;
441 s
->client_cmds
[SENDER_ADD
] = udp_com_add
;
442 s
->client_cmds
[SENDER_DELETE
] = udp_com_delete
;
443 sender_status
= SENDER_OFF
;
444 udp_init_target_list();
445 if (!conf
.udp_no_autostart_given
)
446 sender_status
= SENDER_ON
;
447 PARA_DEBUG_LOG("udp sender init complete\n");