2 * Copyright (C) 2005 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 <netinet/udp.h>
15 #include <arpa/inet.h>
20 #include "server.lsg.h"
30 #include "portable_io.h"
33 #include "close_on_fork.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 /** The opaque structure returned by vss_add_fec_client(). */
47 struct fec_client
*fc
;
48 /** The FEC parameters for this target. */
49 struct fec_client_parms fcp
;
50 /** Whether we already sent the FEC eof packet to this target. */
54 static struct list_head targets
;
55 static int sender_status
;
57 static void udp_close_target(struct sender_client
*sc
)
61 struct udp_target
*ut
= sc
->private_data
;
65 PARA_NOTICE_LOG("sending FEC EOF\n");
66 len
= vss_get_fec_eof_packet(&buf
);
67 /* Ignore write() errors since we are closing the target anyway. */
68 if (write(sc
->fd
, buf
, len
))
69 do_nothing
; /* avoid "ignoring return value" warning */
70 ut
->sent_fec_eof
= true;
73 static void udp_delete_target(struct sender_client
*sc
, const char *msg
)
75 struct udp_target
*ut
= sc
->private_data
;
77 PARA_NOTICE_LOG("deleting %s (%s) from list\n", sc
->name
, msg
);
80 del_close_on_fork_list(sc
->fd
);
81 vss_del_fec_client(ut
->fc
);
89 * Perform AF-independent multicast sender setup.
91 * \param sc The connected sender client.
93 * \return Zero if okay, negative on error.
95 static int mcast_sender_setup(struct sender_client
*sc
)
97 struct sockaddr_storage ss
;
98 socklen_t sslen
= sizeof(ss
);
99 int ttl
= OPT_INT32_VAL(UDP_TTL
), id
= 0;
102 if (OPT_GIVEN(UDP_MCAST_IFACE
)) {
103 const char *iface
= OPT_STRING_VAL(UDP_MCAST_IFACE
);
105 id
= if_nametoindex(iface
);
107 PARA_WARNING_LOG("could not resolve interface '%s', "
108 "using default", iface
);
111 if (getpeername(sc
->fd
, (struct sockaddr
*)&ss
, &sslen
) < 0)
113 assert(ss
.ss_family
== AF_INET
|| ss
.ss_family
== AF_INET6
);
115 /* RFC 3493, 5.2: -1 means 'use kernel default' */
116 if (ttl
< 0 || ttl
> 255)
119 switch (ss
.ss_family
) {
121 if (!IN_MULTICAST(htonl(((struct sockaddr_in
*)&ss
)->sin_addr
.s_addr
)))
127 memset(&mn
, 0, sizeof(mn
));
129 if (setsockopt(sc
->fd
, IPPROTO_IP
, IP_MULTICAST_IF
, &mn
, sizeof(mn
)) < 0)
132 PARA_ERROR_LOG("No support for setting outgoing IPv4 mcast interface.");
136 * Enable receiving multicast messages generated on the local host
137 * At least on Linux, this is enabled by default.
139 if (setsockopt(sc
->fd
, IPPROTO_IP
, IP_MULTICAST_LOOP
, &on
, sizeof(on
)) < 0)
142 /* Default: use local subnet (do not flood out into the WAN) */
145 if (setsockopt(sc
->fd
, IPPROTO_IP
, IP_MULTICAST_TTL
, &ttl
, sizeof(ttl
)) < 0)
149 if (!IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6
*)&ss
)->sin6_addr
))
152 setsockopt(sc
->fd
, IPPROTO_IPV6
, IPV6_MULTICAST_IF
, &id
, sizeof(id
)) < 0)
154 if (setsockopt(sc
->fd
, IPPROTO_IPV6
, IPV6_MULTICAST_LOOP
, &on
, sizeof(on
)) < 0)
156 if (setsockopt(sc
->fd
, IPPROTO_IPV6
, IPV6_MULTICAST_HOPS
, &ttl
, sizeof(ttl
)) < 0)
161 return -ERRNO_TO_PARA_ERROR(errno
);
164 static void udp_shutdown_targets(void)
166 struct sender_client
*sc
, *tmp
;
167 list_for_each_entry_safe(sc
, tmp
, &targets
, node
)
168 udp_close_target(sc
);
171 static int udp_resolve_target(const char *url
, struct sender_command_data
*scd
)
176 ret
= parse_fec_url(url
, scd
);
179 port
= scd
->port
> 0 ? scd
->port
: OPT_UINT32_VAL(UDP_DEFAULT_PORT
);
181 ret
= para_connect_simple(IPPROTO_UDP
, scd
->host
, port
);
185 result
= remote_name(ret
);
188 if (!parse_url(result
, scd
->host
, sizeof(scd
->host
), &scd
->port
))
189 return -E_ADDRESS_LOOKUP
;
193 static int udp_com_on(__a_unused
struct sender_command_data
*scd
)
195 sender_status
= SENDER_on
;
199 static int udp_com_off(__a_unused
struct sender_command_data
*scd
)
201 udp_shutdown_targets();
202 sender_status
= SENDER_off
;
206 static struct sender_client
*udp_lookup_target(struct sender_command_data
*scd
)
208 struct sender_client
*sc
, *tmp
;
209 char host
[MAX_HOSTLEN
];
212 list_for_each_entry_safe(sc
, tmp
, &targets
, node
) {
213 parse_url(sc
->name
, host
, sizeof(host
), &port
);
215 /* Unspecified port means wildcard port match */
216 if (scd
->port
> 0 && scd
->port
!= port
)
218 if (strcmp(host
, scd
->host
))
225 static int udp_com_delete(struct sender_command_data
*scd
)
227 struct sender_client
*sc
= udp_lookup_target(scd
);
230 udp_delete_target(sc
, "com_delete");
233 PARA_NOTICE_LOG("not deleting non-existing target '%s'\n", scd
->host
);
234 return -E_TARGET_NOT_FOUND
;
237 /** Initialize UDP session and set maximum payload size. */
238 static int udp_init_fec(struct sender_client
*sc
)
240 struct udp_target
*ut
= sc
->private_data
;
243 PARA_NOTICE_LOG("sending to udp %s\n", sc
->name
);
244 ut
->sent_fec_eof
= false;
245 mps
= generic_max_transport_msg_size(sc
->fd
) - sizeof(struct udphdr
);
246 PARA_INFO_LOG("current MPS = %d bytes\n", mps
);
250 /** Check and clear socket error if any. */
251 static int udp_check_socket_state(struct sender_client
*sc
)
253 struct udp_target
*ut
= sc
->private_data
;
255 socklen_t errlen
= sizeof(ret
);
257 if (getsockopt(sc
->fd
, SOL_SOCKET
, SO_ERROR
, &ret
, &errlen
) < 0) {
258 PARA_ERROR_LOG("SO_ERROR failed: %s\n", strerror(ret
));
260 } else if (ret
== 0) {
262 } else if (ret
== ECONNREFUSED
) {
263 time_t dist
= now
->tv_sec
- ut
->last_unreachable
;
265 if (dist
<= UDP_MAX_UNREACHABLE_TIME
) {
267 } else if (dist
> 2 * UDP_MAX_UNREACHABLE_TIME
) {
268 ut
->last_unreachable
= now
->tv_sec
;
272 * unreachable_time < dist <= 2 * unreachable_time
273 * No errors are allowed during this time window.
275 PARA_NOTICE_LOG("Evicting %s after %d seconds "
276 "of connection errors.\n",
277 sc
->name
, (int)dist
);
280 return -ERRNO_TO_PARA_ERROR(ret
);
283 static void udp_send_fec(struct sender_client
*sc
, char *buf
, size_t len
)
287 if (sender_status
== SENDER_off
)
291 ret
= udp_check_socket_state(sc
);
294 ret
= xwrite(sc
->fd
, buf
, len
);
295 if (ret
== -ERRNO_TO_PARA_ERROR(ECONNREFUSED
)) {
297 * Happens if meanwhile an ICMP Destination / Port Unreachable
298 * has arrived. Ignore, persistent errors will be caught above.
306 udp_delete_target(sc
, para_strerror(-ret
));
309 static int udp_com_add(struct sender_command_data
*scd
)
312 struct udp_target
*ut
;
313 struct sender_client
*sc
= udp_lookup_target(scd
);
316 PARA_NOTICE_LOG("target %s already exists - not adding it\n",
318 return -E_TARGET_EXISTS
;
320 ut
= para_calloc(sizeof(*ut
));
321 sc
= para_calloc(sizeof(*sc
));
322 ut
->fcp
.slices_per_group
= scd
->slices_per_group
;
323 ut
->fcp
.data_slices_per_group
= scd
->data_slices_per_group
;
324 ut
->fcp
.init_fec
= udp_init_fec
;
325 ut
->fcp
.send_fec
= udp_send_fec
;
326 ut
->fcp
.need_periodic_header
= true;
328 sc
->private_data
= ut
;
330 ret
= para_connect_simple(IPPROTO_UDP
, scd
->host
, scd
->port
);
335 ret
= mcast_sender_setup(sc
);
338 ret
= mark_fd_nonblocking(sc
->fd
);
341 sc
->name
= para_strdup(remote_name(sc
->fd
));
342 PARA_INFO_LOG("adding to target list (%s)\n", sc
->name
);
343 ut
->fc
= vss_add_fec_client(sc
, &ut
->fcp
);
344 para_list_add(&sc
->node
, &targets
);
345 add_close_on_fork_list(sc
->fd
);
350 PARA_NOTICE_LOG("failed to set up %s:%d (%s)- not adding it\n",
351 scd
->host
, scd
->port
, para_strerror(-ret
));
357 static char *udp_status(void)
359 struct sender_client
*sc
;
360 char *ret
, *tgts
= NULL
;
362 list_for_each_entry(sc
, &targets
, node
) {
363 struct udp_target
*ut
= sc
->private_data
;
364 char *tmp
= make_message("%s%s/%u:%u ",
365 tgts
? : "", sc
->name
,
366 ut
->fcp
.data_slices_per_group
,
367 ut
->fcp
.slices_per_group
376 (sender_status
== SENDER_on
)? "on" : "off",
377 stringify_port(OPT_UINT32_VAL(UDP_DEFAULT_PORT
), "udp"),
378 tgts
? tgts
: "(none)"
384 static void udp_init_target_list(void)
386 struct sender_command_data scd
;
389 INIT_LIST_HEAD(&targets
);
390 for (i
= 0; i
< OPT_GIVEN(UDP_TARGET
); i
++) {
391 const char *arg
= lls_string_val(i
, OPT_RESULT(UDP_TARGET
));
392 if (udp_resolve_target(arg
, &scd
) < 0)
393 PARA_CRIT_LOG("not adding requested target '%s'\n",
400 static char *udp_help(void)
404 "usage: {add|delete} ip_address[:port][/[packet_size:]k:n]\n"
405 " - k is the number of data slices per FEC group\n"
406 " - n is the total number of slices in a FEC group\n"
407 " - packet_size reduces the slice size below path MTU\n\n"
408 "examples: add 224.0.1.38:1500 (IPv4 multicast)\n"
409 " add 224.0.1.38:8080/14:16 (explicit FEC)\n"
410 " add 10.10.1.42 (using default port)\n"
411 " add [FF05::42]:1500 (IPv6 multicast)\n"
412 " add [::1] (IPv6 localhost/default port)\n"
413 " delete myhost.net (host with port wildcard)\n"
414 " delete 10.1.2.3:456 (IPv4 with explicit port)\n"
415 " delete [badc0de::1] (IPv6 with port wildcard)\n"
420 * The init function of para_server's udp sender.
422 * \param s Pointer to the udp sender struct.
424 * It initializes all function pointers of \a s and the list of udp targets.
426 void udp_send_init(struct sender
*s
)
428 INIT_LIST_HEAD(&targets
);
429 s
->status
= udp_status
;
432 s
->pre_select
= NULL
;
433 s
->post_select
= NULL
;
434 s
->shutdown_clients
= udp_shutdown_targets
;
435 s
->resolve_target
= udp_resolve_target
;
436 s
->client_cmds
[SENDER_on
] = udp_com_on
;
437 s
->client_cmds
[SENDER_off
] = udp_com_off
;
438 s
->client_cmds
[SENDER_deny
] = NULL
;
439 s
->client_cmds
[SENDER_allow
] = NULL
;
440 s
->client_cmds
[SENDER_add
] = udp_com_add
;
441 s
->client_cmds
[SENDER_delete
] = udp_com_delete
;
442 sender_status
= SENDER_off
;
443 udp_init_target_list();
444 if (!OPT_GIVEN(UDP_NO_AUTOSTART
))
445 sender_status
= SENDER_on
;
446 PARA_DEBUG_LOG("udp sender init complete\n");