udp_recv.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 /** \file udp_recv.c Paraslash's udp receiver */
   7
   8 #include <regex.h>
   9 #include <dirent.h>
  10 #include <sys/socket.h>
  11 #include <net/if.h>
  12
  13 #include "para.h"
  14 #include "error.h"
  15 #include "portable_io.h"
  16 #include "list.h"
  17 #include "sched.h"
  18 #include "ggo.h"
  19 #include "recv.h"
  20 #include "udp_recv.cmdline.h"
  21 #include "string.h"
  22 #include "net.h"
  23 #include "fd.h"
  24 #include "buffer_tree.h"
  25
  26 /** The size of the receiver node buffer. */
  27 #define UDP_RECV_CHUNK_SIZE (128 * 1024)
  28 /**
  29  * Data specific to the udp receiver.
  30  *
  31  * \sa \ref receiver, \ref receiver_node.
  32  */
  33 struct private_udp_recv_data {
  34         /** The socket file descriptor. */
  35         int fd;
  36         struct btr_pool *btrp;
  37 };
  38
  39 static void udp_recv_pre_select(struct sched *s, struct task *t)
  40 {
  41         struct receiver_node *rn = container_of(t, struct receiver_node, task);
  42         struct private_udp_recv_data *purd = rn->private_data;
  43         int ret;
  44
  45         if (rn->btrn) {
  46                 ret = generic_recv_pre_select(s, t);
  47                 if (ret <= 0)
  48                         return;
  49         }
  50         para_fd_set(purd->fd, &s->rfds, &s->max_fileno);
  51 }
  52
  53 static int enough_space(size_t nbytes, size_t loaded)
  54 {
  55         return nbytes + loaded < UDP_RECV_CHUNK_SIZE;
  56 }
  57
  58 static int add_rn_output(struct receiver_node *rn, char *buf, size_t len)
  59 {
  60         if (!len)
  61                 return 1;
  62         if (!enough_space(len, rn->loaded))
  63                 return -E_UDP_OVERRUN;
  64         memcpy(rn->buf + rn->loaded, buf, len);
  65         rn->loaded += len;
  66         return 1;
  67 }
  68
  69 static void udp_recv_post_select_nobtr(__a_unused struct sched *s, struct task *t)
  70 {
  71         struct receiver_node *rn = container_of(t, struct receiver_node, task);
  72         struct private_udp_recv_data *purd = rn->private_data;
  73         int ret;
  74         char tmpbuf[UDP_RECV_CHUNK_SIZE];
  75         size_t packet_size;
  76
  77         if (rn->output_error && *rn->output_error < 0) {
  78                 t->error = *rn->output_error;
  79                 return;
  80         }
  81         if (!FD_ISSET(purd->fd, &s->rfds))
  82                 return;
  83         ret = recv_bin_buffer(purd->fd, tmpbuf, UDP_RECV_CHUNK_SIZE);
  84         if (ret < 0) {
  85                 if (is_errno(ret, EINTR) || is_errno(ret, EAGAIN))
  86                         goto success;
  87                 t->error = ret;
  88                 return;
  89         }
  90         t->error = -E_RECV_EOF;
  91         if (!ret)
  92                 return;
  93         packet_size = ret;
  94         if (packet_size >= FEC_EOF_PACKET_LEN)
  95                 if (!memcmp(tmpbuf, FEC_EOF_PACKET, FEC_EOF_PACKET_LEN))
  96                         return;
  97         t->error = add_rn_output(rn, tmpbuf, packet_size);
  98         if (t->error < 0)
  99                 return;
 100 success:
 101         t->error = 1;
 102 }
 103
 104 static void udp_recv_post_select_btr(__a_unused struct sched *s, struct task *t)
 105 {
 106         struct receiver_node *rn = container_of(t, struct receiver_node, task);
 107         struct private_udp_recv_data *purd = rn->private_data;
 108         struct btr_node *btrn = rn->btrn;
 109         int ret;
 110         char *buf = NULL;
 111         size_t packet_size, bufsize;
 112
 113         t->error = 0;
 114         ret = btr_node_status(btrn, 0, BTR_NT_ROOT);
 115         if (ret < 0)
 116                 goto err;
 117         if (ret == 0)
 118                 return;
 119         if (!FD_ISSET(purd->fd, &s->rfds))
 120                 return;
 121         bufsize = btr_pool_get_buffer(purd->btrp, &buf);
 122         ret = -E_UDP_OVERRUN;
 123         if (bufsize == 0)
 124                 goto err;
 125         ret = recv_bin_buffer(purd->fd, buf, bufsize);
 126         if (ret == 0)
 127                 ret = -E_RECV_EOF;
 128         if (ret < 0)
 129                 goto err;
 130         packet_size = ret;
 131         if (packet_size >= FEC_EOF_PACKET_LEN) {
 132                 if (!memcmp(buf, FEC_EOF_PACKET, FEC_EOF_PACKET_LEN)) {
 133                         PARA_INFO_LOG("received eof packet\n");
 134                         ret = -E_RECV_EOF;
 135                         goto err;
 136                 }
 137         }
 138         btr_add_output_pool(purd->btrp, packet_size, btrn);
 139         return;
 140 err:
 141         btr_remove_node(btrn);
 142         t->error = ret;
 143         close(purd->fd);
 144         purd->fd = -1;
 145 }
 146
 147 static void udp_recv_post_select(__a_unused struct sched *s, struct task *t)
 148 {
 149         struct receiver_node *rn = container_of(t, struct receiver_node, task);
 150         if (rn->btrn)
 151                 return udp_recv_post_select_btr(s, t);
 152         udp_recv_post_select_nobtr(s, t);
 153 }
 154
 155 static void udp_shutdown(void)
 156 {
 157         return;
 158 }
 159
 160 static void udp_recv_close(struct receiver_node *rn)
 161 {
 162         struct private_udp_recv_data *purd = rn->private_data;
 163
 164         if (purd->fd >= 0)
 165                 close(purd->fd);
 166         btr_pool_free(purd->btrp);
 167         free(rn->private_data);
 168         free(rn->buf);
 169 }
 170
 171 static void *udp_recv_parse_config(int argc, char **argv)
 172 {
 173         int ret;
 174         struct udp_recv_args_info *tmp =
 175                 para_calloc(sizeof(struct udp_recv_args_info));
 176
 177         ret = udp_recv_cmdline_parser(argc, argv, tmp)? -E_UDP_SYNTAX : 1;
 178         if (ret >= 0)
 179                 return tmp;
 180         free(tmp);
 181         return NULL;
 182 }
 183
 184 /*
 185  * Perform AF-independent joining of multicast receive addresses.
 186  *
 187  * \param fd    Bound socket descriptor.
 188  * \param iface The receiving multicast interface, or NULL for the default.
 189  *
 190  * \return Zero if okay, negative on error.
 191  */
 192 static int mcast_receiver_setup(int fd, const char *iface)
 193 {
 194         struct sockaddr_storage ss;
 195         socklen_t sslen = sizeof(ss);
 196         int id = iface == NULL ? 0 : if_nametoindex(iface);
 197
 198         if (getsockname(fd, (struct sockaddr *)&ss, &sslen) < 0)
 199                 goto err;
 200
 201         if (iface != NULL && id == 0)
 202                 PARA_WARNING_LOG("could not resolve interface %s, using default", iface);
 203
 204         switch (ss.ss_family) {
 205         case AF_INET:
 206                 if (IN_MULTICAST(htonl(((struct sockaddr_in *)&ss)->sin_addr.s_addr))) {
 207 #ifdef HAVE_IP_MREQN
 208                         struct ip_mreqn m4;
 209
 210                         m4.imr_address.s_addr   = INADDR_ANY;
 211                         m4.imr_ifindex          = id;
 212 #else
 213                         struct ip_mreq m4;
 214
 215                         m4.imr_interface.s_addr = INADDR_ANY;
 216                         if (id != 0)
 217                                 PARA_ERROR_LOG("Setting IPv4 receiver mcast interface not supported.");
 218
 219 #endif
 220                         m4.imr_multiaddr        = ((struct sockaddr_in *)&ss)->sin_addr;
 221
 222                         if (setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &m4, sizeof(m4)) < 0)
 223                                 break;
 224                 }
 225                 return 0;
 226         case AF_INET6:
 227                 if (IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6 *)&ss)->sin6_addr)) {
 228                         struct ipv6_mreq m6;
 229
 230                         memset(&m6, 0, sizeof(m6));
 231                         memcpy(&m6.ipv6mr_multiaddr, &((struct sockaddr_in6 *)&ss)->sin6_addr, 16);
 232                         m6.ipv6mr_interface = id;
 233                         if (setsockopt(fd, IPPROTO_IPV6, IPV6_JOIN_GROUP, &m6, sizeof(m6)) < 0)
 234                                 break;
 235                 }
 236                 return 0;
 237         default:
 238                 PARA_ERROR_LOG("address family %d not supported", ss.ss_family);
 239                 return -E_ADDRESS_LOOKUP;
 240         }
 241 err:
 242         return -ERRNO_TO_PARA_ERROR(errno);
 243 }
 244
 245 static int udp_recv_open(struct receiver_node *rn)
 246 {
 247         struct private_udp_recv_data *purd;
 248         struct udp_recv_args_info *c = rn->conf;
 249         char  *iface = c->iface_given ? c->iface_arg : NULL;
 250         int ret;
 251
 252         rn->buf = para_calloc(UDP_RECV_CHUNK_SIZE);
 253         rn->private_data = para_calloc(sizeof(struct private_udp_recv_data));
 254         purd = rn->private_data;
 255
 256         ret = makesock(AF_UNSPEC, IPPROTO_UDP, 1, c->host_arg, c->port_arg);
 257         if (ret < 0)
 258                 goto err;
 259         purd->fd = ret;
 260
 261         ret = mcast_receiver_setup(purd->fd, iface);
 262         if (ret < 0) {
 263                 close(purd->fd);
 264                 return ret;
 265         }
 266
 267         ret = mark_fd_nonblocking(purd->fd);
 268         if (ret < 0) {
 269                 close(purd->fd);
 270                 goto err;
 271         }
 272         PARA_INFO_LOG("receiving from %s:%d, fd=%d\n", c->host_arg,
 273                 c->port_arg, purd->fd);
 274         purd->btrp = btr_pool_new("udp_recv", 320 * 1024);
 275         return purd->fd;
 276 err:
 277         free(rn->private_data);
 278         free(rn->buf);
 279         return ret;
 280 }
 281
 282 static void udp_recv_free_config(void *conf)
 283 {
 284         udp_recv_cmdline_parser_free(conf);
 285 }
 286
 287 /**
 288  * The init function of the udp receiver.
 289  *
 290  * \param r Pointer to the receiver struct to initialize.
 291  *
 292  * Initialize all function pointers of \a r.
 293  */
 294 void udp_recv_init(struct receiver *r)
 295 {
 296         struct udp_recv_args_info dummy;
 297
 298         udp_recv_cmdline_parser_init(&dummy);
 299         r->shutdown = udp_shutdown;
 300         r->open = udp_recv_open;
 301         r->close = udp_recv_close;
 302         r->pre_select = udp_recv_pre_select;
 303         r->post_select = udp_recv_post_select;
 304         r->parse_config = udp_recv_parse_config;
 305         r->free_config = udp_recv_free_config;
 306         r->help = (struct ggo_help) {
 307                 .short_help = udp_recv_args_info_help,
 308                 .detailed_help = udp_recv_args_info_detailed_help
 309         };
 310         udp_recv_cmdline_parser_free(&dummy);
 311 }