libgssdp/gssdp-socket-source.c

   1 /*
   2  * Copyright (C) 2006, 2007, 2008 OpenedHand Ltd.
   3  * Copyright (C) 2009 Nokia Corporation, all rights reserved.
   4  *
   5  * Author: Jorn Baayen <jorn@openedhand.com>
   6  *         Zeeshan Ali (Khattak) <zeeshanak@gnome.org>
   7  *                               <zeeshan.ali@nokia.com>
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Library General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2 of the License, or (at your option) any later version.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Library General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Library General Public
  20  * License along with this library; if not, write to the
  21  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  22  * Boston, MA 02111-1307, USA.
  23  */
  24
  25 #include <config.h>
  26 #include <glib.h>
  27 #include <sys/socket.h>
  28 #include <sys/types.h>
  29 #include <netinet/in.h>
  30 #include <arpa/inet.h>
  31 #include <string.h>
  32 #include <stdio.h>
  33 #include <errno.h>
  34 #include <unistd.h>
  35
  36 #include "gssdp-socket-source.h"
  37 #include "gssdp-protocol.h"
  38
  39 struct _GSSDPSocketSource {
  40         GSource source;
  41
  42         GPollFD poll_fd;
  43 };
  44
  45 static gboolean
  46 gssdp_socket_source_prepare  (GSource    *source,
  47                               int        *timeout);
  48 static gboolean
  49 gssdp_socket_source_check    (GSource    *source);
  50 static gboolean
  51 gssdp_socket_source_dispatch (GSource    *source,
  52                               GSourceFunc callback,
  53                               gpointer    user_data);
  54 static void
  55 gssdp_socket_source_finalize (GSource    *source);
  56
  57 static const GSourceFuncs gssdp_socket_source_funcs = {
  58         gssdp_socket_source_prepare,
  59         gssdp_socket_source_check,
  60         gssdp_socket_source_dispatch,
  61         gssdp_socket_source_finalize
  62 };
  63
  64 /**
  65  * gssdp_socket_source_new
  66  *
  67  * Return value: A new #GSSDPSocketSource
  68  **/
  69 GSSDPSocketSource *
  70 gssdp_socket_source_new (GSSDPSocketSourceType type,
  71                          const char           *host_ip)
  72 {
  73         GSource *source;
  74         GSSDPSocketSource *socket_source;
  75         struct sockaddr_in bind_addr;
  76         struct in_addr iface_addr;
  77         struct ip_mreq mreq;
  78         gboolean boolean = TRUE;
  79         guchar ttl = 4;
  80         int res;
  81
  82         /* Create source */
  83         source = g_source_new ((GSourceFuncs*)&gssdp_socket_source_funcs,
  84                                sizeof (GSSDPSocketSource));
  85
  86         socket_source = (GSSDPSocketSource *) source;
  87
  88         /* Create socket */
  89         socket_source->poll_fd.fd = socket (AF_INET,
  90                                             SOCK_DGRAM,
  91                                             IPPROTO_UDP);
  92         if (socket_source->poll_fd.fd == -1)
  93                 goto error;
  94
  95         socket_source->poll_fd.events = G_IO_IN | G_IO_ERR;
  96
  97         g_source_add_poll (source, &socket_source->poll_fd);
  98
  99         /* Enable broadcasting */
 100         res = setsockopt (socket_source->poll_fd.fd,
 101                           SOL_SOCKET,
 102                           SO_BROADCAST,
 103                           &boolean,
 104                           sizeof (boolean));
 105         if (res == -1)
 106                 goto error;
 107
 108         /* TTL */
 109         res = setsockopt (socket_source->poll_fd.fd,
 110                           IPPROTO_IP,
 111                           IP_MULTICAST_TTL,
 112                           &ttl,
 113                           sizeof (ttl));
 114         if (res == -1)
 115                 goto error;
 116
 117         memset (&bind_addr, 0, sizeof (bind_addr));
 118         bind_addr.sin_family = AF_INET;
 119
 120         res = inet_aton (host_ip, &iface_addr);
 121         if (res == 0)
 122                 goto error;
 123
 124         /* Set up additional things according to the type of socket desired */
 125         if (type == GSSDP_SOCKET_SOURCE_TYPE_MULTICAST) {
 126                 /* Allow multiple sockets to use the same PORT number */
 127                 res = setsockopt (socket_source->poll_fd.fd,
 128                                   SOL_SOCKET,
 129 #ifdef SO_REUSEPORT
 130                                   SO_REUSEPORT,
 131 #else
 132                                   SO_REUSEADDR,
 133 #endif
 134                                   &boolean,
 135                                   sizeof (boolean));
 136                 if (res == -1)
 137                         goto error;
 138
 139                 /* Enable multicast loopback */
 140                 res = setsockopt (socket_source->poll_fd.fd,
 141                                   IPPROTO_IP,
 142                                   IP_MULTICAST_LOOP,
 143                                   &boolean,
 144                                   sizeof (boolean));
 145                 if (res == -1)
 146                        goto error;
 147
 148                 /* Set the interface */
 149                 res = setsockopt (socket_source->poll_fd.fd,
 150                                   IPPROTO_IP,
 151                                   IP_MULTICAST_IF,
 152                                   &iface_addr,
 153                                   sizeof (struct in_addr));
 154                 if (res == -1)
 155                         goto error;
 156
 157                 /* Subscribe to multicast channel */
 158                 res = inet_aton (SSDP_ADDR, &(mreq.imr_multiaddr));
 159                 if (res == 0)
 160                         goto error;
 161
 162                 memcpy (&(mreq.imr_interface),
 163                         &iface_addr,
 164                         sizeof (struct in_addr));
 165
 166                 res = setsockopt (socket_source->poll_fd.fd,
 167                                   IPPROTO_IP,
 168                                   IP_ADD_MEMBERSHIP,
 169                                   &mreq,
 170                                   sizeof (mreq));
 171                 if (res == -1)
 172                         goto error;
 173
 174                 bind_addr.sin_port = htons (SSDP_PORT);
 175                 res = inet_aton (SSDP_ADDR, &(bind_addr.sin_addr));
 176                 if (res == 0)
 177                         goto error;
 178         } else {
 179                 bind_addr.sin_port = 0;
 180                 memcpy (&(bind_addr.sin_addr),
 181                         &iface_addr,
 182                         sizeof (struct in_addr));
 183         }
 184
 185         /* Bind to requested port and address */
 186         res = bind (socket_source->poll_fd.fd,
 187                     (struct sockaddr *) &bind_addr,
 188                     sizeof (bind_addr));
 189         if (res == -1)
 190                 goto error;
 191
 192         return socket_source;
 193
 194 error:
 195         g_source_destroy (source);
 196
 197         return NULL;
 198 }
 199
 200 static gboolean
 201 gssdp_socket_source_prepare (GSource *source,
 202                              int     *timeout)
 203 {
 204         return FALSE;
 205 }
 206
 207 static gboolean
 208 gssdp_socket_source_check (GSource *source)
 209 {
 210         GSSDPSocketSource *socket_source;
 211
 212         socket_source = (GSSDPSocketSource *) source;
 213
 214         return socket_source->poll_fd.revents & (G_IO_IN | G_IO_ERR);
 215 }
 216
 217 static gboolean
 218 gssdp_socket_source_dispatch (GSource    *source,
 219                               GSourceFunc callback,
 220                               gpointer    user_data)
 221 {
 222         GSSDPSocketSource *socket_source;
 223
 224         socket_source = (GSSDPSocketSource *) source;
 225
 226         if (socket_source->poll_fd.revents & G_IO_IN) {
 227                 /* Ready to read */
 228                 if (callback)
 229                         callback (user_data);
 230         } else if (socket_source->poll_fd.revents & G_IO_ERR) {
 231                 /* Error */
 232                 int value;
 233                 socklen_t size_int;
 234
 235                 value = EINVAL;
 236                 size_int = sizeof (int);
 237
 238                 /* Get errno from socket */
 239                 getsockopt (socket_source->poll_fd.fd,
 240                             SOL_SOCKET,
 241                             SO_ERROR,
 242                             &value,
 243                             &size_int);
 244
 245                 g_warning ("Socket error %d received: %s",
 246                            value,
 247                            strerror (value));
 248         }
 249
 250         return TRUE;
 251 }
 252
 253 static void
 254 gssdp_socket_source_finalize (GSource *source)
 255 {
 256         GSSDPSocketSource *socket_source;
 257
 258         socket_source = (GSSDPSocketSource *) source;
 259
 260         /* Close the socket */
 261         close (socket_source->poll_fd.fd);
 262 }
 263
 264 /**
 265  * gssdp_socket_source_get_fd
 266  *
 267  * Return value: The socket's FD.
 268  **/
 269 int
 270 gssdp_socket_source_get_fd (GSSDPSocketSource *socket_source)
 271 {
 272         g_return_val_if_fail (socket_source != NULL, -1);
 273
 274         return socket_source->poll_fd.fd;
 275 }