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