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 "audiod.h"
  22 #include "string.h"
  23 #include "net.h"
  24 #include "fd.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 };
  37
  38 static void udp_recv_pre_select(struct sched *s, struct task *t)
  39 {
  40         struct receiver_node *rn = container_of(t, struct receiver_node, task);
  41         struct private_udp_recv_data *purd = rn->private_data;
  42
  43         para_fd_set(purd->fd, &s->rfds, &s->max_fileno);
  44 }
  45
  46 static int enough_space(size_t nbytes, size_t loaded)
  47 {
  48         return nbytes + loaded < UDP_RECV_CHUNK_SIZE;
  49 }
  50
  51 static int add_rn_output(struct receiver_node *rn, char *buf, size_t len)
  52 {
  53         if (!len)
  54                 return 1;
  55         if (!enough_space(len, rn->loaded))
  56                 return -E_UDP_OVERRUN;
  57         memcpy(rn->buf + rn->loaded, buf, len);
  58         rn->loaded += len;
  59         return 1;
  60 }
  61
  62 static void udp_recv_post_select(__a_unused struct sched *s, struct task *t)
  63 {
  64         struct receiver_node *rn = container_of(t, struct receiver_node, task);
  65         struct private_udp_recv_data *purd = rn->private_data;
  66         int ret;
  67         char tmpbuf[UDP_RECV_CHUNK_SIZE];
  68         size_t packet_size;
  69
  70         if (rn->output_error && *rn->output_error < 0) {
  71                 t->error = *rn->output_error;
  72                 return;
  73         }
  74         if (!FD_ISSET(purd->fd, &s->rfds))
  75                 return;
  76         ret = recv_bin_buffer(purd->fd, tmpbuf, UDP_RECV_CHUNK_SIZE);
  77         if (ret < 0) {
  78                 if (is_errno(ret, EINTR) || is_errno(ret, EAGAIN))
  79                         goto success;
  80                 t->error = ret;
  81                 return;
  82         }
  83         t->error = -E_RECV_EOF;
  84         if (!ret)
  85                 return;
  86         packet_size = ret;
  87         if (packet_size >= FEC_EOF_PACKET_LEN)
  88                 if (!memcmp(tmpbuf, FEC_EOF_PACKET, FEC_EOF_PACKET_LEN))
  89                         return;
  90         t->error = add_rn_output(rn, tmpbuf, packet_size);
  91         if (t->error < 0)
  92                 return;
  93 success:
  94         t->error = 1;
  95 }
  96
  97 static void udp_shutdown(void)
  98 {
  99         return;
 100 }
 101
 102 static void udp_recv_close(struct receiver_node *rn)
 103 {
 104         struct private_udp_recv_data *purd = rn->private_data;
 105
 106         if (purd->fd >= 0)
 107                 close(purd->fd);
 108         free(rn->private_data);
 109         free(rn->buf);
 110 }
 111
 112 static void *udp_recv_parse_config(int argc, char **argv)
 113 {
 114         int ret;
 115         struct udp_recv_args_info *tmp =
 116                 para_calloc(sizeof(struct udp_recv_args_info));
 117
 118         ret = udp_recv_cmdline_parser(argc, argv, tmp)? -E_UDP_SYNTAX : 1;
 119         if (ret >= 0)
 120                 return tmp;
 121         free(tmp);
 122         return NULL;
 123 }
 124
 125 /*
 126  * Perform AF-independent joining of multicast receive addresses.
 127  *
 128  * \param fd    Bound socket descriptor.
 129  * \param iface The receiving multicast interface, or NULL for the default.
 130  *
 131  * \return Zero if okay, negative on error.
 132  */
 133 static int mcast_receiver_setup(int fd, const char *iface)
 134 {
 135         struct sockaddr_storage ss;
 136         socklen_t sslen = sizeof(ss);
 137         int id = iface == NULL ? 0 : if_nametoindex(iface);
 138
 139         if (getsockname(fd, (struct sockaddr *)&ss, &sslen) < 0)
 140                 goto err;
 141
 142         if (iface != NULL && id == 0)
 143                 PARA_WARNING_LOG("could not resolve interface %s, using default", iface);
 144
 145         switch (ss.ss_family) {
 146         case AF_INET:
 147                 if (IN_MULTICAST(htonl(((struct sockaddr_in *)&ss)->sin_addr.s_addr))) {
 148 #ifdef HAVE_IP_MREQN
 149                         struct ip_mreqn m4;
 150
 151                         m4.imr_address.s_addr   = INADDR_ANY;
 152                         m4.imr_ifindex          = id;
 153 #else
 154                         struct ip_mreq m4;
 155
 156                         m4.imr_interface.s_addr = INADDR_ANY;
 157                         if (id != 0)
 158                                 PARA_ERROR_LOG("Setting IPv4 receiver mcast interface not supported.");
 159
 160 #endif
 161                         m4.imr_multiaddr        = ((struct sockaddr_in *)&ss)->sin_addr;
 162
 163                         if (setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &m4, sizeof(m4)) < 0)
 164                                 break;
 165                 }
 166                 return 0;
 167         case AF_INET6:
 168                 if (IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6 *)&ss)->sin6_addr)) {
 169                         struct ipv6_mreq m6;
 170
 171                         memset(&m6, 0, sizeof(m6));
 172                         memcpy(&m6.ipv6mr_multiaddr, &((struct sockaddr_in6 *)&ss)->sin6_addr, 16);
 173                         m6.ipv6mr_interface = id;
 174                         if (setsockopt(fd, IPPROTO_IPV6, IPV6_JOIN_GROUP, &m6, sizeof(m6)) < 0)
 175                                 break;
 176                 }
 177                 return 0;
 178         default:
 179                 PARA_ERROR_LOG("address family %d not supported", ss.ss_family);
 180                 return -E_ADDRESS_LOOKUP;
 181         }
 182 err:
 183         return -ERRNO_TO_PARA_ERROR(errno);
 184 }
 185
 186 static int udp_recv_open(struct receiver_node *rn)
 187 {
 188         struct private_udp_recv_data *purd;
 189         struct udp_recv_args_info *c = rn->conf;
 190         char  *iface = c->iface_given ? c->iface_arg : NULL;
 191         int ret;
 192
 193         rn->buf = para_calloc(UDP_RECV_CHUNK_SIZE);
 194         rn->private_data = para_calloc(sizeof(struct private_udp_recv_data));
 195         purd = rn->private_data;
 196
 197         ret = makesock(AF_UNSPEC, IPPROTO_UDP, 1, c->host_arg, c->port_arg);
 198         if (ret < 0)
 199                 goto err;
 200         purd->fd = ret;
 201
 202         ret = mcast_receiver_setup(purd->fd, iface);
 203         if (ret < 0) {
 204                 close(purd->fd);
 205                 return ret;
 206         }
 207
 208         ret = mark_fd_nonblocking(purd->fd);
 209         if (ret < 0)
 210                 goto err;
 211         PARA_NOTICE_LOG("receiving from %s:%d, fd=%d\n", c->host_arg,
 212                 c->port_arg, purd->fd);
 213         return purd->fd;
 214 err:
 215         free(rn->private_data);
 216         free(rn->buf);
 217         return ret;
 218 }
 219
 220 /**
 221  * The init function of the udp receiver.
 222  *
 223  * \param r Pointer to the receiver struct to initialize.
 224  *
 225  * Initialize all function pointers of \a r.
 226  */
 227 void udp_recv_init(struct receiver *r)
 228 {
 229         struct udp_recv_args_info dummy;
 230
 231         udp_recv_cmdline_parser_init(&dummy);
 232         r->shutdown = udp_shutdown;
 233         r->open = udp_recv_open;
 234         r->close = udp_recv_close;
 235         r->pre_select = udp_recv_pre_select;
 236         r->post_select = udp_recv_post_select;
 237         r->parse_config = udp_recv_parse_config;
 238         r->help = (struct ggo_help) {
 239                 .short_help = udp_recv_args_info_help,
 240                 .detailed_help = udp_recv_args_info_detailed_help
 241         };
 242         udp_recv_cmdline_parser_free(&dummy);
 243 }