2 device.c -- multicast socket
3 Copyright (C) 2002-2005 Ivo Timmermans,
4 2002-2014 Guus Sliepen <guus@tinc-vpn.org>
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License along
17 with this program; if not, write to the Free Software Foundation, Inc.,
18 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
32 static char *device_info;
34 static uint64_t device_total_in = 0;
35 static uint64_t device_total_out = 0;
37 static struct addrinfo *ai = NULL;
38 static mac_t ignore_src = {{0}};
40 static bool setup_device(void) {
46 device_info = "multicast socket";
48 get_config_string(lookup_config(config_tree, "Interface"), &iface);
50 if(!get_config_string(lookup_config(config_tree, "Device"), &device)) {
51 logger(LOG_ERR, "Device variable required for %s", device_info);
55 host = xstrdup(device);
56 space = strchr(host, ' ');
59 logger(LOG_ERR, "Port number required for %s", device_info);
66 space = strchr(port, ' ');
73 ai = str2addrinfo(host, port, SOCK_DGRAM);
80 device_fd = socket(ai->ai_family, SOCK_DGRAM, IPPROTO_UDP);
83 logger(LOG_ERR, "Creating socket failed: %s", sockstrerror(sockerrno));
89 fcntl(device_fd, F_SETFD, FD_CLOEXEC);
92 static const int one = 1;
93 setsockopt(device_fd, SOL_SOCKET, SO_REUSEADDR, (void *)&one, sizeof(one));
95 if(bind(device_fd, ai->ai_addr, ai->ai_addrlen)) {
96 closesocket(device_fd);
97 logger(LOG_ERR, "Can't bind to %s %s: %s", host, port, sockstrerror(sockerrno));
102 switch(ai->ai_family) {
103 #ifdef IP_ADD_MEMBERSHIP
107 struct sockaddr_in in;
108 memcpy(&in, ai->ai_addr, sizeof(in));
109 mreq.imr_multiaddr.s_addr = in.sin_addr.s_addr;
110 mreq.imr_interface.s_addr = htonl(INADDR_ANY);
112 if(setsockopt(device_fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, (void *)&mreq, sizeof(mreq))) {
113 logger(LOG_ERR, "Cannot join multicast group %s %s: %s", host, port, sockstrerror(sockerrno));
114 closesocket(device_fd);
119 #ifdef IP_MULTICAST_LOOP
120 setsockopt(device_fd, IPPROTO_IP, IP_MULTICAST_LOOP, (const void *)&one, sizeof(one));
122 #ifdef IP_MULTICAST_TTL
123 setsockopt(device_fd, IPPROTO_IP, IP_MULTICAST_TTL, (void *)&ttl, sizeof(ttl));
129 #ifdef IPV6_JOIN_GROUP
132 struct ipv6_mreq mreq;
133 struct sockaddr_in6 in6;
134 memcpy(&in6, ai->ai_addr, sizeof(in6));
135 memcpy(&mreq.ipv6mr_multiaddr, &in6.sin6_addr, sizeof(mreq.ipv6mr_multiaddr));
136 mreq.ipv6mr_interface = in6.sin6_scope_id;
138 if(setsockopt(device_fd, IPPROTO_IPV6, IPV6_JOIN_GROUP, (void *)&mreq, sizeof(mreq))) {
139 logger(LOG_ERR, "Cannot join multicast group %s %s: %s", host, port, sockstrerror(sockerrno));
140 closesocket(device_fd);
145 #ifdef IPV6_MULTICAST_LOOP
146 setsockopt(device_fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, (const void *)&one, sizeof(one));
148 #ifdef IPV6_MULTICAST_HOPS
149 setsockopt(device_fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, (void *)&ttl, sizeof(ttl));
156 logger(LOG_ERR, "Multicast for address family %x unsupported", ai->ai_family);
157 closesocket(device_fd);
163 logger(LOG_INFO, "%s is a %s", device, device_info);
168 static void close_device(void) {
179 static bool read_packet(vpn_packet_t *packet) {
182 if((lenin = recv(device_fd, (void *)packet->data, MTU, 0)) <= 0) {
183 logger(LOG_ERR, "Error while reading from %s %s: %s", device_info,
184 device, strerror(errno));
188 if(!memcmp(&ignore_src, packet->data + 6, sizeof(ignore_src))) {
189 ifdebug(SCARY_THINGS) logger(LOG_DEBUG, "Ignoring loopback packet of %d bytes from %s", lenin, device_info);
196 device_total_in += packet->len;
198 ifdebug(TRAFFIC) logger(LOG_DEBUG, "Read packet of %d bytes from %s", packet->len,
204 static bool write_packet(vpn_packet_t *packet) {
205 ifdebug(TRAFFIC) logger(LOG_DEBUG, "Writing packet of %d bytes to %s",
206 packet->len, device_info);
208 if(sendto(device_fd, (void *)packet->data, packet->len, 0, ai->ai_addr, ai->ai_addrlen) < 0) {
209 logger(LOG_ERR, "Can't write to %s %s: %s", device_info, device,
214 device_total_out += packet->len;
216 memcpy(&ignore_src, packet->data + 6, sizeof(ignore_src));
221 static void dump_device_stats(void) {
222 logger(LOG_DEBUG, "Statistics for %s %s:", device_info, device);
223 logger(LOG_DEBUG, " total bytes in: %10"PRIu64, device_total_in);
224 logger(LOG_DEBUG, " total bytes out: %10"PRIu64, device_total_out);
227 const devops_t multicast_devops = {
228 .setup = setup_device,
229 .close = close_device,
231 .write = write_packet,
232 .dump_stats = dump_device_stats,
237 static bool not_supported(void) {
238 logger(LOG_ERR, "Raw socket device not supported on this platform");
242 const devops_t multicast_devops = {
243 .setup = not_supported,