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 position of this target in the list of targets. */
  37         struct list_head node;
  38         /** The hostname (DNS name or IPv4/v6 address string). */
  39         char host[MAX_HOSTLEN];
  40         /** The UDP port. */
  41         int port;
  42         /** The socket fd. */
  43         int fd;
  44         /** The list of queued chunks for this fd. */
  45         struct chunk_queue *cq;
  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 };
  51
  52 static struct list_head targets;
  53 static int sender_status;
  54 static struct sender *self;
  55
  56 static void udp_close_target(struct udp_target *ut)
  57 {
  58         if (ut->fd < 0)
  59                 return;
  60         close(ut->fd);
  61         del_close_on_fork_list(ut->fd);
  62         cq_destroy(ut->cq);
  63         ut->cq = NULL;
  64         ut->fd = -1;
  65 }
  66
  67 static void udp_delete_target(struct udp_target *ut, const char *msg)
  68 {
  69         PARA_NOTICE_LOG("deleting %s#%d (%s) from list\n", ut->host,
  70                 ut->port, msg);
  71         udp_close_target(ut);
  72         vss_del_fec_client(ut->fc);
  73         list_del(&ut->node);
  74         free(ut);
  75 }
  76
  77 /**
  78  * Perform AF-independent multicast sender setup.
  79  *
  80  * \param fd    The connected socket descriptor.
  81  * \param ttl   UDPv4 multicast TTL or UDPv6 multicast number of hops.
  82  *              Use -1 to mean default, 0..255 otherwise.
  83  * \param iface The outgoing multicast interface, or NULL for the default.
  84  *
  85  * \return Zero if okay, negative on error.
  86  */
  87 static int mcast_sender_setup(struct udp_target *ut, int ttl, char *iface)
  88 {
  89         struct sockaddr_storage ss;
  90         socklen_t sslen = sizeof(ss);
  91
  92         const int on = 1;
  93         int id = iface == NULL ? 0 : if_nametoindex(iface);
  94
  95         if (getpeername(ut->fd, (struct sockaddr *)&ss, &sslen) < 0)
  96                 goto err;
  97
  98         if (iface != NULL && id == 0)
  99                 PARA_WARNING_LOG("could not resolve interface %s, using default", iface);
 100
 101         /* RFC 3493, 5.2: -1 means 'use kernel default' */
 102         if (ttl < 0 || ttl > 255)
 103                 ttl = -1;
 104
 105         switch (ss.ss_family) {
 106         case AF_INET:
 107                 if (!IN_MULTICAST(htonl(((struct sockaddr_in *)&ss)->sin_addr.s_addr)))
 108                         return 0;
 109                 if (id != 0) {
 110 #ifdef HAVE_IP_MREQN
 111                         struct ip_mreqn mn;
 112
 113                         memset(&mn, 0, sizeof(mn));
 114                         mn.imr_ifindex = id;
 115                         if (setsockopt(ut->fd, IPPROTO_IP, IP_MULTICAST_IF, &mn, sizeof(mn)) < 0)
 116                                 goto err;
 117 #else
 118                         PARA_ERROR_LOG("No support for setting outgoing IPv4 mcast interface.");
 119 #endif
 120                 }
 121                 /*
 122                  * Enable receiving multicast messages generated on the local host
 123                  * At least on Linux, this is enabled by default.
 124                  */
 125                 if (setsockopt(ut->fd, IPPROTO_IP, IP_MULTICAST_LOOP, &on, sizeof(on)) < 0)
 126                         break;
 127
 128                 /* Default: use local subnet (do not flood out into the WAN) */
 129                 if (ttl == -1)
 130                         ttl = 1;
 131                 if (setsockopt(ut->fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)) < 0)
 132                         break;
 133                 return 0;
 134         case AF_INET6:
 135                 if (!IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6 *)&ss)->sin6_addr))
 136                         return 0;
 137                 if (id != 0 &&
 138                     setsockopt(ut->fd, IPPROTO_IPV6, IPV6_MULTICAST_IF, &id, sizeof(id)) < 0)
 139                         break;
 140                 if (setsockopt(ut->fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &on, sizeof(on)) < 0)
 141                         break;
 142                 if (setsockopt(ut->fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl)) < 0)
 143                         break;
 144                 return 0;
 145         default:
 146                 PARA_ERROR_LOG("address family %d not supported", ss.ss_family);
 147                 return -E_ADDRESS_LOOKUP;
 148         }
 149 err:
 150         return -ERRNO_TO_PARA_ERROR(errno);
 151 }
 152
 153 /** The maximal size of the per-target chunk queue. */
 154 #define UDP_CQ_BYTES 40000
 155
 156 static int udp_open(void *client, struct fec_client_parms **fcp)
 157 {
 158         struct udp_target *ut = client;
 159         int ret;
 160         char *iface = NULL;
 161
 162         if (ut->fd >= 0) /* nothing to do */
 163                 return 0;
 164
 165         ret = para_connect_simple(IPPROTO_UDP, ut->host, ut->port);
 166         if (ret < 0)
 167                 return ret;
 168         ut->fd = ret;
 169
 170         if (conf.udp_mcast_iface_given)
 171                 iface = conf.udp_mcast_iface_arg;
 172
 173         ret = mcast_sender_setup(ut, conf.udp_ttl_arg, iface);
 174         if (ret < 0) {
 175                 close(ut->fd);
 176                 return ret;
 177         }
 178
 179         ret = mark_fd_nonblocking(ut->fd);
 180         if (ret < 0) {
 181                 close(ut->fd);
 182                 return ret;
 183         }
 184         add_close_on_fork_list(ut->fd);
 185         ut->cq = cq_new(UDP_CQ_BYTES);
 186         ut->fcp.max_slice_bytes = 1472; /* FIXME */
 187         *fcp = &ut->fcp;
 188         PARA_NOTICE_LOG("sending to udp %s#%d\n", ut->host, ut->port);
 189         return 1;
 190 }
 191
 192 static void udp_shutdown_targets(void)
 193 {
 194         struct udp_target *ut, *tmp;
 195         const char *buf = NULL;
 196         size_t len = 0; /* STFU, gcc */
 197
 198         list_for_each_entry_safe(ut, tmp, &targets, node) {
 199                 int ubuntu_glibc_headers_suck;
 200                 if (ut->fd < 0)
 201                         continue;
 202                 if (!buf)
 203                         len = vss_get_fec_eof_packet(&buf);
 204                 /* ignore return value, we're closing the target anyway. */
 205                 ubuntu_glibc_headers_suck = write(ut->fd, buf, len); /* STFU */
 206                 udp_close_target(ut);
 207         }
 208 }
 209
 210 static int udp_com_on(__a_unused struct sender_command_data *scd)
 211 {
 212         sender_status = SENDER_ON;
 213         return 1;
 214 }
 215
 216 static int udp_com_off(__a_unused struct sender_command_data *scd)
 217 {
 218         udp_shutdown_targets();
 219         sender_status = SENDER_OFF;
 220         return 1;
 221 }
 222
 223 static int udp_com_delete(struct sender_command_data *scd)
 224 {
 225         struct udp_target *ut, *tmp;
 226
 227         list_for_each_entry_safe(ut, tmp, &targets, node) {
 228                 /* Unspecified port means wildcard port match */
 229                 if (scd->port > 0 && scd->port != ut->port)
 230                         continue;
 231                 if (strcmp(ut->host, scd->host))
 232                         continue;
 233                 udp_delete_target(ut, "com_delete");
 234         }
 235         return 1;
 236 }
 237
 238 static int udp_send_fec(char *buf, size_t len, void *private_data)
 239 {
 240         struct udp_target *ut = private_data;
 241         int ret;
 242
 243         if (sender_status == SENDER_OFF)
 244                 return 0;
 245         ret = send_queued_chunks(ut->fd, ut->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(ut->cq, buf, len);
 254                 assert(ret >= 0);
 255         }
 256         ret = write_nonblock(ut->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(ut->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(struct udp_target));
 274
 275         strncpy(ut->host, scd->host, sizeof(ut->host));
 276         ut->port = scd->port > 0 ? scd->port : conf.udp_default_port_arg;
 277         ut->fd = -1; /* not yet connected */
 278         PARA_INFO_LOG("adding to target list (%s#%d)\n", ut->host, ut->port);
 279         para_list_add(&ut->node, &targets);
 280         ut->fcp.slices_per_group = scd->slices_per_group;
 281         ut->fcp.data_slices_per_group = scd->data_slices_per_group;
 282         vss_add_fec_client(self, ut, &ut->fc);
 283 }
 284
 285 static int udp_com_add(struct sender_command_data *scd)
 286 {
 287         udp_add_target(scd);
 288         return 1;
 289 }
 290
 291 static char *udp_info(void)
 292 {
 293         struct udp_target *ut;
 294         char *ret, *tgts = NULL;
 295
 296         list_for_each_entry(ut, &targets, node) {
 297                 bool is_v6 = strchr(ut->host, ':') != NULL;
 298                 char *tmp = make_message("%s%s%s%s:%d/%u:%u:%u ", tgts ? : "",
 299                         is_v6 ? "[" : "", ut->host,
 300                         is_v6 ? "]" : "", ut->port,
 301                         ut->fcp.max_slice_bytes,
 302                         ut->fcp.data_slices_per_group,
 303                         ut->fcp.slices_per_group
 304                 );
 305                 free(tgts);
 306                 tgts = tmp;
 307         }
 308         ret = make_message(
 309                 "udp sender:\n"
 310                 "\tstatus: %s\n"
 311                 "\tport: %s\n"
 312                 "\ttargets: %s\n",
 313                 (sender_status == SENDER_ON)? "on" : "off",
 314                 stringify_port(conf.udp_default_port_arg, "udp"),
 315                 tgts? tgts : "(none)"
 316         );
 317         free(tgts);
 318         return ret;
 319 }
 320
 321 static void udp_init_target_list(void)
 322 {
 323         struct sender_command_data scd;
 324         int i;
 325
 326         INIT_LIST_HEAD(&targets);
 327         for (i = 0; i < conf.udp_target_given; i++) {
 328                 if (parse_fec_url(conf.udp_target_arg[i], &scd) < 0) {
 329                         PARA_CRIT_LOG("syntax error for udp target option "
 330                                 "#%d, ignoring\n", i);
 331                         continue;
 332                 }
 333                 udp_add_target(&scd);
 334         }
 335 }
 336
 337 static char *udp_help(void)
 338 {
 339         return make_message(
 340                 "usage: {on|off}\n"
 341                 "usage: {add|delete} host[:port][/packet_size:k:n]\n"
 342                 "examples: add 224.0.1.38:1500  (IPv4 multicast)\n"
 343                 "          add 224.0.1.38:1500/1400:14:16\n"
 344                 "              (likewise, using 1400 byte packets, with 14\n"
 345                 "               data slices per 16 slice FEC group)\n"
 346                 "          add 10.10.1.42       (using default port)\n"
 347                 "          add [FF05::42]:1500  (IPv6 multicast)\n"
 348                 "          add [::1]            (IPv6 localhost/default port)\n"
 349                 "          delete myhost.net    (host with port wildcard)\n"
 350                 "          delete [badc0de::1]  (IPv6 with port wildcard)\n"
 351         );
 352 }
 353
 354 /**
 355  * The init function of para_server's udp sender.
 356  *
 357  * \param s Pointer to the udp sender struct.
 358  *
 359  * It initializes all function pointers of \a s and the list of udp targets.
 360  */
 361 void udp_send_init(struct sender *s)
 362 {
 363         INIT_LIST_HEAD(&targets);
 364         s->info = udp_info;
 365         s->help = udp_help;
 366         s->send = NULL;
 367         s->send_fec = udp_send_fec;
 368         s->open = udp_open;
 369         s->pre_select = NULL;
 370         s->post_select = NULL;
 371         s->shutdown_clients = udp_shutdown_targets;
 372         s->client_cmds[SENDER_ON] = udp_com_on;
 373         s->client_cmds[SENDER_OFF] = udp_com_off;
 374         s->client_cmds[SENDER_DENY] = NULL;
 375         s->client_cmds[SENDER_ALLOW] = NULL;
 376         s->client_cmds[SENDER_ADD] = udp_com_add;
 377         s->client_cmds[SENDER_DELETE] = udp_com_delete;
 378         sender_status = SENDER_OFF;
 379         udp_init_target_list();
 380         if (!conf.udp_no_autostart_given)
 381                 sender_status = SENDER_ON;
 382         self = s;
 383         PARA_DEBUG_LOG("udp sender init complete\n");
 384 }