udp_send.c

   1 /*
   2  * Copyright (C) 2005-2009 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 <sys/time.h>
  11 #include <dirent.h>
  12 #include <net/if.h>
  13
  14 #include "server.cmdline.h"
  15 #include "para.h"
  16 #include "error.h"
  17 #include "string.h"
  18 #include "afh.h"
  19 #include "afs.h"
  20 #include "server.h"
  21 #include "vss.h"
  22 #include "list.h"
  23 #include "send.h"
  24 #include "portable_io.h"
  25 #include "net.h"
  26 #include "fd.h"
  27 #include "sched.h"
  28 #include "close_on_fork.h"
  29 #include "chunk_queue.h"
  30
  31 /** Describes one entry in the list of targets for the udp sender. */
  32 struct udp_target {
  33         /** The position of this target in the list of targets. */
  34         struct list_head node;
  35         /** The hostname (DNS name or IPv4/v6 address string). */
  36         char host[MAX_HOSTLEN];
  37         /** The UDP port. */
  38         int port;
  39         /** The socket fd. */
  40         int fd;
  41         /** The list of queued chunks for this fd. */
  42         struct chunk_queue *cq;
  43         struct fec_client *fc;
  44         struct fec_client_parms fcp;
  45 };
  46
  47 static struct list_head targets;
  48 static int sender_status;
  49
  50 static void udp_close_target(struct udp_target *ut)
  51 {
  52         if (ut->fd < 0)
  53                 return;
  54         close(ut->fd);
  55         del_close_on_fork_list(ut->fd);
  56         cq_destroy(ut->cq);
  57         ut->cq = NULL;
  58         ut->fd = -1;
  59 }
  60
  61 static void udp_delete_target(struct udp_target *ut, const char *msg)
  62 {
  63         PARA_NOTICE_LOG("deleting %s#%d (%s) from list\n", ut->host,
  64                 ut->port, msg);
  65         udp_close_target(ut);
  66         vss_del_fec_client(ut->fc);
  67         list_del(&ut->node);
  68         free(ut);
  69 }
  70
  71 /**
  72  * Perform AF-independent multicast sender setup.
  73  *
  74  * \param fd    The connected socket descriptor.
  75  * \param ttl   UDPv4 multicast TTL or UDPv6 multicast number of hops.
  76  *              Use -1 to mean default, 0..255 otherwise.
  77  * \param iface The outgoing multicast interface, or NULL for the default.
  78  *
  79  * \return Zero if okay, negative on error.
  80  */
  81 static int mcast_sender_setup(struct udp_target *ut, int ttl, char *iface)
  82 {
  83         struct sockaddr_storage ss;
  84         socklen_t sslen = sizeof(ss);
  85
  86         const int on = 1;
  87         int id = iface == NULL ? 0 : if_nametoindex(iface);
  88
  89         if (getpeername(ut->fd, (struct sockaddr *)&ss, &sslen) < 0)
  90                 goto err;
  91
  92         if (iface != NULL && id == 0)
  93                 PARA_WARNING_LOG("could not resolve interface %s, using default", iface);
  94
  95         /* RFC 3493, 5.2: -1 means 'use kernel default' */
  96         if (ttl < 0 || ttl > 255)
  97                 ttl = -1;
  98
  99         switch (ss.ss_family) {
 100         case AF_INET:
 101                 if (!IN_MULTICAST(htonl(((struct sockaddr_in *)&ss)->sin_addr.s_addr)))
 102                         return 0;
 103                 if (id != 0) {
 104 #ifdef HAVE_IP_MREQN
 105                         struct ip_mreqn mn;
 106
 107                         memset(&mn, 0, sizeof(mn));
 108                         mn.imr_ifindex = id;
 109                         if (setsockopt(ut->fd, IPPROTO_IP, IP_MULTICAST_IF, &mn, sizeof(mn)) < 0)
 110                                 goto err;
 111 #else
 112                         PARA_ERROR_LOG("No support for setting outgoing IPv4 mcast interface.");
 113 #endif
 114                 }
 115                 /*
 116                  * Enable receiving multicast messages generated on the local host
 117                  * At least on Linux, this is enabled by default.
 118                  */
 119                 if (setsockopt(ut->fd, IPPROTO_IP, IP_MULTICAST_LOOP, &on, sizeof(on)) < 0)
 120                         break;
 121
 122                 /* Default: use local subnet (do not flood out into the WAN) */
 123                 if (ttl == -1)
 124                         ttl = 1;
 125                 if (setsockopt(ut->fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)) < 0)
 126                         break;
 127                 return 0;
 128         case AF_INET6:
 129                 if (!IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6 *)&ss)->sin6_addr))
 130                         return 0;
 131                 if (id != 0 &&
 132                     setsockopt(ut->fd, IPPROTO_IPV6, IPV6_MULTICAST_IF, &id, sizeof(id)) < 0)
 133                         break;
 134                 if (setsockopt(ut->fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &on, sizeof(on)) < 0)
 135                         break;
 136                 if (setsockopt(ut->fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl)) < 0)
 137                         break;
 138                 return 0;
 139         default:
 140                 PARA_ERROR_LOG("address family %d not supported", ss.ss_family);
 141                 return -E_ADDRESS_LOOKUP;
 142         }
 143 err:
 144         return -ERRNO_TO_PARA_ERROR(errno);
 145 }
 146
 147 /** The maximal size of the per-target chunk queue. */
 148 #define UDP_CQ_BYTES 40000
 149
 150 static int udp_init_session(struct udp_target *ut)
 151 {
 152         int ret;
 153         char *iface = NULL;
 154
 155         if (ut->fd >= 0) /* nothing to do */
 156                 return 0;
 157
 158         ret = makesock(AF_UNSPEC, IPPROTO_UDP, 0, ut->host, ut->port);
 159         if (ret < 0)
 160                 return ret;
 161         ut->fd = ret;
 162
 163         if (conf.udp_mcast_iface_given)
 164                 iface = conf.udp_mcast_iface_arg;
 165
 166         ret = mcast_sender_setup(ut, conf.udp_ttl_arg, iface);
 167         if (ret < 0) {
 168                 close(ut->fd);
 169                 return ret;
 170         }
 171
 172         ret = mark_fd_nonblocking(ut->fd);
 173         if (ret < 0) {
 174                 close(ut->fd);
 175                 return ret;
 176         }
 177         add_close_on_fork_list(ut->fd);
 178         ut->cq = cq_new(UDP_CQ_BYTES);
 179         PARA_NOTICE_LOG("sending to udp %s#%d\n", ut->host, ut->port);
 180         return 1;
 181 }
 182
 183 static void udp_shutdown_targets(void)
 184 {
 185         struct udp_target *ut, *tmp;
 186         const char *buf = NULL;
 187         size_t len = 0; /* STFU, gcc */
 188
 189         list_for_each_entry_safe(ut, tmp, &targets, node) {
 190                 if (ut->fd < 0)
 191                         continue;
 192                 if (!buf)
 193                         len = vss_get_fec_eof_packet(&buf);
 194                 write(ut->fd, buf, len);
 195                 udp_close_target(ut);
 196         }
 197 }
 198
 199 static int udp_com_on(__a_unused struct sender_command_data *scd)
 200 {
 201         sender_status = SENDER_ON;
 202         return 1;
 203 }
 204
 205 static int udp_com_off(__a_unused struct sender_command_data *scd)
 206 {
 207         udp_shutdown_targets();
 208         sender_status = SENDER_OFF;
 209         return 1;
 210 }
 211
 212 static int udp_com_delete(struct sender_command_data *scd)
 213 {
 214         struct udp_target *ut, *tmp;
 215
 216         list_for_each_entry_safe(ut, tmp, &targets, node) {
 217                 /* Unspecified port means wildcard port match */
 218                 if (scd->port > 0 && scd->port != ut->port)
 219                         continue;
 220                 if (strcmp(ut->host, scd->host))
 221                         continue;
 222                 udp_delete_target(ut, "com_delete");
 223         }
 224         return 1;
 225 }
 226
 227 static int udp_send_fec(char *buf, size_t len, void *private_data)
 228 {
 229         struct udp_target *ut = private_data;
 230         int ret = udp_init_session(ut);
 231
 232         if (ret < 0)
 233                 goto fail;
 234         ret = send_queued_chunks(ut->fd, ut->cq, 0);
 235         if (ret < 0)
 236                 goto fail;
 237         if (!len)
 238                 return 0;
 239         if (!ret) { /* still data left in the queue */
 240                 ret = cq_enqueue(ut->cq, buf, len);
 241                 if (ret < 0)
 242                         goto fail;
 243         }
 244         ret = write_nonblock(ut->fd, buf, len, 0);
 245         if (ret < 0)
 246                 goto fail;
 247         if (ret != len) {
 248                 ret = cq_enqueue(ut->cq, buf + ret, len - ret);
 249                 if (ret < 0)
 250                         goto fail;
 251         }
 252         return 1;
 253 fail:
 254         udp_delete_target(ut, para_strerror(-ret));
 255         return ret;
 256 }
 257
 258 static void udp_add_target(const char *host, int port)
 259 {
 260         struct udp_target *ut = para_calloc(sizeof(struct udp_target));
 261
 262         strncpy(ut->host, host, sizeof(ut->host));
 263         ut->port = port > 0 ? port : conf.udp_default_port_arg;
 264         ut->fd = -1; /* not yet connected */
 265         PARA_INFO_LOG("adding to target list (%s#%d)\n",
 266                       ut->host, ut->port);
 267         para_list_add(&ut->node, &targets);
 268         ut->fcp.slices_per_group = 16;
 269         ut->fcp.data_slices_per_group = 14;
 270         ut->fcp.max_slice_bytes = 1400;
 271         ut->fcp.send = udp_send_fec;
 272         ut->fcp.private_data = ut;
 273         vss_add_fec_client(&ut->fcp, &ut->fc);
 274 }
 275
 276 static int udp_com_add(struct sender_command_data *scd)
 277 {
 278         udp_add_target(scd->host, scd->port);
 279         return 1;
 280 }
 281
 282 static char *udp_info(void)
 283 {
 284         struct udp_target *ut;
 285         char *ret, *tgts = NULL;
 286
 287         list_for_each_entry(ut, &targets, node) {
 288                 bool is_v6 = strchr(ut->host, ':') != NULL;
 289                 char *tmp = make_message("%s%s%s%s:%d ", tgts ? : "",
 290                                          is_v6 ? "[" : "", ut->host,
 291                                          is_v6 ? "]" : "", ut->port);
 292                 free(tgts);
 293                 tgts = tmp;
 294         }
 295         ret = make_message(
 296                 "udp sender:\n"
 297                 "\tstatus: %s\n"
 298                 "\tport: udp %d\n"
 299                 "\ttargets: %s\n",
 300                 (sender_status == SENDER_ON)? "on" : "off",
 301                 conf.udp_default_port_arg,
 302                 tgts? tgts : "(none)"
 303         );
 304         free(tgts);
 305         return ret;
 306 }
 307
 308 static void udp_init_target_list(void)
 309 {
 310         char    host[MAX_HOSTLEN];
 311         int     port, i;
 312
 313         INIT_LIST_HEAD(&targets);
 314         for (i = 0; i < conf.udp_target_given; i++)
 315                 if (parse_url(conf.udp_target_arg[i], host,
 316                                         sizeof(host), &port) == NULL)
 317                         PARA_CRIT_LOG("syntax error for udp target option "
 318                                       "#%d, ignoring\n", i);
 319                 else
 320                         udp_add_target(host, port);
 321 }
 322
 323 static char *udp_help(void)
 324 {
 325         return make_message(
 326                 "usage: {on|off}\n"
 327                 "usage: {add|delete} host[:port]\n"
 328                 "examples: add 224.0.1.38:1500  (IPv4 multicast)\n"
 329                 "          add 10.10.1.42       (using default port)\n"
 330                 "          add [FF05::42]:1500  (IPv6 multicast)\n"
 331                 "          add [::1]            (IPv6 localhost/default port)\n"
 332                 "          delete myhost.net    (host with port wildcard)\n"
 333                 "          delete [badc0de::1]  (IPv6 with port wildcard)\n"
 334         );
 335 }
 336
 337 /**
 338  * The init function of para_server's udp sender.
 339  *
 340  * \param s Pointer to the http sender struct.
 341  *
 342  * It initializes all function pointers of \a s and the list of udp targets.
 343  */
 344 void udp_send_init(struct sender *s)
 345 {
 346         INIT_LIST_HEAD(&targets);
 347         s->info = udp_info;
 348         s->help = udp_help;
 349         s->send = NULL;
 350         s->pre_select = NULL;
 351         s->post_select = NULL;
 352         s->shutdown_clients = udp_shutdown_targets;
 353         s->client_cmds[SENDER_ON] = udp_com_on;
 354         s->client_cmds[SENDER_OFF] = udp_com_off;
 355         s->client_cmds[SENDER_DENY] = NULL;
 356         s->client_cmds[SENDER_ALLOW] = NULL;
 357         s->client_cmds[SENDER_ADD] = udp_com_add;
 358         s->client_cmds[SENDER_DELETE] = udp_com_delete;
 359         sender_status = SENDER_OFF;
 360         udp_init_target_list();
 361         if (!conf.udp_no_autostart_given)
 362                 sender_status = SENDER_ON;
 363         PARA_DEBUG_LOG("udp sender init complete\n");
 364 }