udp_send.c

   1 /*
   2  * Copyright (C) 2005-2010 Andre Noll <maan@systemlinux.org>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6
   7 /** \file udp_send.c Para_server's udp sender. */
   8
   9
  10 #include <regex.h>
  11 #include <sys/time.h>
  12 #include <dirent.h>
  13 #include <sys/socket.h>
  14 #include <netinet/udp.h>
  15 #include <net/if.h>
  16 #include <osl.h>
  17
  18 #include "server.cmdline.h"
  19 #include "para.h"
  20 #include "error.h"
  21 #include "string.h"
  22 #include "afh.h"
  23 #include "afs.h"
  24 #include "server.h"
  25 #include "list.h"
  26 #include "send.h"
  27 #include "vss.h"
  28 #include "portable_io.h"
  29 #include "net.h"
  30 #include "fd.h"
  31 #include "sched.h"
  32 #include "close_on_fork.h"
  33 #include "chunk_queue.h"
  34
  35 /** Describes one entry in the list of targets for the udp sender. */
  36 struct udp_target {
  37         /** The hostname (DNS name or IPv4/v6 address string). */
  38         char host[MAX_HOSTLEN];
  39         /** The UDP port. */
  40         int port;
  41         /** Common sender client data */
  42         struct sender_client *sc;
  43         /** The opaque structure returned by vss_add_fec_client(). */
  44         struct fec_client *fc;
  45         /** The FEC parameters for this target. */
  46         struct fec_client_parms fcp;
  47 };
  48
  49 static struct list_head targets;
  50 static int sender_status;
  51
  52 static void udp_close_target(struct sender_client *sc)
  53 {
  54         if (sc->fd < 0)
  55                 return;
  56         close(sc->fd);
  57         del_close_on_fork_list(sc->fd);
  58         cq_destroy(sc->cq);
  59         sc->cq   = NULL;
  60         sc->fd   = -1;
  61 }
  62
  63 static void udp_delete_target(struct udp_target *ut, const char *msg)
  64 {
  65
  66         PARA_NOTICE_LOG("deleting %s#%d (%s) from list\n", ut->host,
  67                 ut->port, msg);
  68         udp_close_target(ut->sc);
  69         vss_del_fec_client(ut->fc);
  70         list_del(&ut->sc->node);
  71         free(ut->sc);
  72         free(ut);
  73 }
  74
  75 /**
  76  * Perform AF-independent multicast sender setup.
  77  *
  78  * \param sc    The connected sender client.
  79  * \param ttl   UDPv4 multicast TTL or UDPv6 multicast number of hops.
  80  *              Use -1 to mean default, 0..255 otherwise.
  81  * \param iface The outgoing multicast interface, or NULL for the default.
  82  *
  83  * \return Zero if okay, negative on error.
  84  */
  85 static int mcast_sender_setup(struct sender_client *sc, int ttl, char *iface)
  86 {
  87         struct sockaddr_storage ss;
  88         socklen_t sslen = sizeof(ss);
  89
  90         const int on = 1;
  91         int id = iface == NULL ? 0 : if_nametoindex(iface);
  92
  93         if (getpeername(sc->fd, (struct sockaddr *)&ss, &sslen) < 0)
  94                 goto err;
  95
  96         if (iface != NULL && id == 0)
  97                 PARA_WARNING_LOG("could not resolve interface %s, using default", iface);
  98
  99         /* RFC 3493, 5.2: -1 means 'use kernel default' */
 100         if (ttl < 0 || ttl > 255)
 101                 ttl = -1;
 102
 103         switch (ss.ss_family) {
 104         case AF_INET:
 105                 if (!IN_MULTICAST(htonl(((struct sockaddr_in *)&ss)->sin_addr.s_addr)))
 106                         return 0;
 107                 if (id != 0) {
 108 #ifdef HAVE_IP_MREQN
 109                         struct ip_mreqn mn;
 110
 111                         memset(&mn, 0, sizeof(mn));
 112                         mn.imr_ifindex = id;
 113                         if (setsockopt(sc->fd, IPPROTO_IP, IP_MULTICAST_IF, &mn, sizeof(mn)) < 0)
 114                                 goto err;
 115 #else
 116                         PARA_ERROR_LOG("No support for setting outgoing IPv4 mcast interface.");
 117 #endif
 118                 }
 119                 /*
 120                  * Enable receiving multicast messages generated on the local host
 121                  * At least on Linux, this is enabled by default.
 122                  */
 123                 if (setsockopt(sc->fd, IPPROTO_IP, IP_MULTICAST_LOOP, &on, sizeof(on)) < 0)
 124                         break;
 125
 126                 /* Default: use local subnet (do not flood out into the WAN) */
 127                 if (ttl == -1)
 128                         ttl = 1;
 129                 if (setsockopt(sc->fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)) < 0)
 130                         break;
 131                 return 0;
 132         case AF_INET6:
 133                 if (!IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6 *)&ss)->sin6_addr))
 134                         return 0;
 135                 if (id != 0 &&
 136                     setsockopt(sc->fd, IPPROTO_IPV6, IPV6_MULTICAST_IF, &id, sizeof(id)) < 0)
 137                         break;
 138                 if (setsockopt(sc->fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &on, sizeof(on)) < 0)
 139                         break;
 140                 if (setsockopt(sc->fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl)) < 0)
 141                         break;
 142                 return 0;
 143         default:
 144                 PARA_ERROR_LOG("address family %d not supported", ss.ss_family);
 145                 return -E_ADDRESS_LOOKUP;
 146         }
 147 err:
 148         return -ERRNO_TO_PARA_ERROR(errno);
 149 }
 150
 151 /** The maximal size of the per-target chunk queue. */
 152 #define UDP_CQ_BYTES 40000
 153
 154 static int udp_init_session(struct sender_client *sc)
 155 {
 156         struct udp_target *ut = sc->private_data;
 157         int ret;
 158         char *iface = NULL;
 159
 160         if (sc->fd >= 0) /* nothing to do */
 161                 return 0;
 162
 163         ret = para_connect_simple(IPPROTO_UDP, ut->host, ut->port);
 164         if (ret < 0)
 165                 return ret;
 166         sc->fd = ret;
 167
 168         if (conf.udp_mcast_iface_given)
 169                 iface = conf.udp_mcast_iface_arg;
 170
 171         ret = mcast_sender_setup(sc, conf.udp_ttl_arg, iface);
 172         if (ret < 0) {
 173                 close(sc->fd);
 174                 return ret;
 175         }
 176
 177         ret = mark_fd_nonblocking(sc->fd);
 178         if (ret < 0) {
 179                 close(sc->fd);
 180                 return ret;
 181         }
 182         add_close_on_fork_list(sc->fd);
 183         sc->cq   = cq_new(UDP_CQ_BYTES);
 184         PARA_NOTICE_LOG("sending to udp %s#%d\n", ut->host, ut->port);
 185         return 1;
 186 }
 187
 188 static void udp_shutdown_targets(void)
 189 {
 190         struct sender_client *sc, *tmp;
 191         const char *buf = NULL;
 192         size_t len = 0; /* STFU, gcc */
 193
 194         list_for_each_entry_safe(sc, tmp, &targets, node) {
 195                 int ubuntu_glibc_headers_suck;
 196                 if (sc->fd < 0)
 197                         continue;
 198                 if (!buf)
 199                         len = vss_get_fec_eof_packet(&buf);
 200                 /* ignore return value, we're closing the target anyway. */
 201                 ubuntu_glibc_headers_suck = write(sc->fd, buf, len); /* STFU */
 202                 udp_close_target(sc);
 203         }
 204 }
 205
 206 static int udp_com_on(__a_unused struct sender_command_data *scd)
 207 {
 208         sender_status = SENDER_ON;
 209         return 1;
 210 }
 211
 212 static int udp_com_off(__a_unused struct sender_command_data *scd)
 213 {
 214         udp_shutdown_targets();
 215         sender_status = SENDER_OFF;
 216         return 1;
 217 }
 218
 219 static int udp_com_delete(struct sender_command_data *scd)
 220 {
 221         struct sender_client *sc, *tmp;
 222
 223         list_for_each_entry_safe(sc, tmp, &targets, node) {
 224                 struct udp_target *ut = sc->private_data;
 225
 226                 /* Unspecified port means wildcard port match */
 227                 if (scd->port > 0 && scd->port != ut->port)
 228                         continue;
 229                 if (strcmp(ut->host, scd->host))
 230                         continue;
 231                 udp_delete_target(ut, "com_delete");
 232         }
 233         return 1;
 234 }
 235
 236 /** Initialize UDP session and set maximum payload size. */
 237 static int udp_init_fec(struct sender_client *sc)
 238 {
 239         int mps, ret = udp_init_session(sc);
 240
 241         if (ret < 0)
 242                 return ret;
 243
 244         mps = generic_max_transport_msg_size(sc->fd) - sizeof(struct udphdr);
 245         PARA_INFO_LOG("current MPS = %d bytes\n", mps);
 246         return mps;
 247 }
 248
 249 static int udp_send_fec(struct sender_client *sc, char *buf, size_t len)
 250 {
 251         struct udp_target *ut = sc->private_data;
 252         int ret;
 253
 254         if (sender_status == SENDER_OFF)
 255                 return 0;
 256         ret = send_queued_chunks(sc->fd, sc->cq);
 257         if (ret == -ERRNO_TO_PARA_ERROR(ECONNREFUSED))
 258                 ret = 0;
 259         if (ret < 0)
 260                 goto fail;
 261         if (!len)
 262                 return 0;
 263         if (!ret) { /* still data left in the queue */
 264                 ret = cq_force_enqueue(sc->cq, buf, len);
 265                 assert(ret >= 0);
 266                 return 0;
 267         }
 268         ret = write_nonblock(sc->fd, buf, len);
 269         if (ret == -ERRNO_TO_PARA_ERROR(ECONNREFUSED))
 270                 ret = 0;
 271         if (ret < 0)
 272                 goto fail;
 273         if (ret != len) {
 274                 ret = cq_force_enqueue(sc->cq, buf + ret, len - ret);
 275                 assert(ret >= 0);
 276         }
 277         return 1;
 278 fail:
 279         udp_delete_target(ut, para_strerror(-ret));
 280         return ret;
 281 }
 282
 283 static void udp_add_target(struct sender_command_data *scd)
 284 {
 285         struct udp_target *ut = para_calloc(sizeof(*ut));
 286
 287         strncpy(ut->host, scd->host, sizeof(ut->host));
 288         ut->port = scd->port > 0 ? scd->port : conf.udp_default_port_arg;
 289
 290         ut->fcp.slices_per_group      = scd->slices_per_group;
 291         ut->fcp.data_slices_per_group = scd->data_slices_per_group;
 292         ut->fcp.max_slice_bytes       = scd->max_slice_bytes;
 293         ut->fcp.init_fec              = udp_init_fec;
 294         ut->fcp.send_fec              = udp_send_fec;
 295
 296         ut->sc = para_calloc(sizeof(*ut->sc));
 297         ut->sc->fd = -1; /* not yet connected */
 298         ut->sc->private_data = ut;
 299         ut->fc = vss_add_fec_client(ut->sc, &ut->fcp);
 300
 301         PARA_INFO_LOG("adding to target list (%s#%d)\n", ut->host, ut->port);
 302         para_list_add(&ut->sc->node, &targets);
 303 }
 304
 305 static int udp_com_add(struct sender_command_data *scd)
 306 {
 307         udp_add_target(scd);
 308         return 1;
 309 }
 310
 311 static char *udp_info(void)
 312 {
 313         struct sender_client *sc;
 314         char *ret, *tgts = NULL;
 315
 316         list_for_each_entry(sc, &targets, node) {
 317                 struct udp_target *ut = sc->private_data;
 318                 bool is_v6 = strchr(ut->host, ':') != NULL;
 319                 char *tmp = make_message("%s%s%s%s:%d/%u:%u:%u ", tgts ? : "",
 320                         is_v6 ? "[" : "", ut->host,
 321                         is_v6 ? "]" : "", ut->port,
 322                         ut->fcp.max_slice_bytes,
 323                         ut->fcp.data_slices_per_group,
 324                         ut->fcp.slices_per_group
 325                 );
 326                 free(tgts);
 327                 tgts = tmp;
 328         }
 329         ret = make_message(
 330                 "udp sender:\n"
 331                 "\tstatus: %s\n"
 332                 "\tport: %s\n"
 333                 "\ttargets: %s\n",
 334                 (sender_status == SENDER_ON)? "on" : "off",
 335                 stringify_port(conf.udp_default_port_arg, "udp"),
 336                 tgts? tgts : "(none)"
 337         );
 338         free(tgts);
 339         return ret;
 340 }
 341
 342 static void udp_init_target_list(void)
 343 {
 344         struct sender_command_data scd;
 345         int i;
 346
 347         INIT_LIST_HEAD(&targets);
 348         for (i = 0; i < conf.udp_target_given; i++) {
 349                 if (parse_fec_url(conf.udp_target_arg[i], &scd) < 0) {
 350                         PARA_CRIT_LOG("syntax error for udp target option "
 351                                 "#%d, ignoring\n", i);
 352                         continue;
 353                 }
 354                 udp_add_target(&scd);
 355         }
 356 }
 357
 358 static char *udp_help(void)
 359 {
 360         return make_message(
 361                 "usage: {on|off}\n"
 362                 "usage: {add|delete} host[:port][/packet_size:k:n]\n"
 363                 "examples: add 224.0.1.38:1500  (IPv4 multicast)\n"
 364                 "          add 224.0.1.38:1500/1400:14:16\n"
 365                 "              (likewise, using 1400 byte packets, with 14\n"
 366                 "               data slices per 16 slice FEC group)\n"
 367                 "          add 10.10.1.42       (using default port)\n"
 368                 "          add [FF05::42]:1500  (IPv6 multicast)\n"
 369                 "          add [::1]            (IPv6 localhost/default port)\n"
 370                 "          delete myhost.net    (host with port wildcard)\n"
 371                 "          delete [badc0de::1]  (IPv6 with port wildcard)\n"
 372         );
 373 }
 374
 375 /**
 376  * The init function of para_server's udp sender.
 377  *
 378  * \param s Pointer to the udp sender struct.
 379  *
 380  * It initializes all function pointers of \a s and the list of udp targets.
 381  */
 382 void udp_send_init(struct sender *s)
 383 {
 384         INIT_LIST_HEAD(&targets);
 385         s->info = udp_info;
 386         s->help = udp_help;
 387         s->send = NULL;
 388         s->pre_select = NULL;
 389         s->post_select = NULL;
 390         s->shutdown_clients = udp_shutdown_targets;
 391         s->client_cmds[SENDER_ON] = udp_com_on;
 392         s->client_cmds[SENDER_OFF] = udp_com_off;
 393         s->client_cmds[SENDER_DENY] = NULL;
 394         s->client_cmds[SENDER_ALLOW] = NULL;
 395         s->client_cmds[SENDER_ADD] = udp_com_add;
 396         s->client_cmds[SENDER_DELETE] = udp_com_delete;
 397         sender_status = SENDER_OFF;
 398         udp_init_target_list();
 399         if (!conf.udp_no_autostart_given)
 400                 sender_status = SENDER_ON;
 401         PARA_DEBUG_LOG("udp sender init complete\n");
 402 }