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