+/*
+ device.c -- multicast socket
+ Copyright (C) 2002-2005 Ivo Timmermans,
+ 2002-2012 Guus Sliepen <guus@tinc-vpn.org>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#include "system.h"
+
+#include "conf.h"
+#include "device.h"
+#include "net.h"
+#include "logger.h"
+#include "netutl.h"
+#include "utils.h"
+#include "route.h"
+#include "xalloc.h"
+
+static char *device_info;
+
+static uint64_t device_total_in = 0;
+static uint64_t device_total_out = 0;
+
+static struct addrinfo *ai = NULL;
+static mac_t ignore_src = {0};
+
+static bool setup_device(void) {
+ char *host;
+ char *port;
+ char *space;
+ int ttl = 1;
+
+ device_info = "multicast socket";
+
+ get_config_string(lookup_config(config_tree, "Interface"), &iface);
+
+ if(!get_config_string(lookup_config(config_tree, "Device"), &device)) {
+ logger(LOG_ERR, "Device variable required for %s", device_info);
+ return false;
+ }
+
+ host = xstrdup(device);
+ space = strchr(host, ' ');
+ if(!space) {
+ logger(LOG_ERR, "Port number required for %s", device_info);
+ return false;
+ }
+
+ *space++ = 0;
+ port = space;
+ space = strchr(port, ' ');
+
+ if(space) {
+ *space++ = 0;
+ ttl = atoi(space);
+ }
+
+ ai = str2addrinfo(host, port, SOCK_DGRAM);
+ if(!ai)
+ return false;
+
+ device_fd = socket(ai->ai_family, SOCK_DGRAM, IPPROTO_UDP);
+ if(device_fd < 0) {
+ logger(LOG_ERR, "Creating socket failed: %s", sockstrerror(sockerrno));
+ return false;
+ }
+
+#ifdef FD_CLOEXEC
+ fcntl(device_fd, F_SETFD, FD_CLOEXEC);
+#endif
+
+ static const int one = 1;
+ setsockopt(device_fd, SOL_SOCKET, SO_REUSEADDR, (void *)&one, sizeof one);
+
+ if(bind(device_fd, ai->ai_addr, ai->ai_addrlen)) {
+ closesocket(device_fd);
+ logger(LOG_ERR, "Can't bind to %s %s: %s", host, port, sockstrerror(sockerrno));
+ return false;
+ }
+
+ switch(ai->ai_family) {
+ case AF_INET: {
+ struct ip_mreq mreq;
+ struct sockaddr_in in;
+ memcpy(&in, ai->ai_addr, sizeof in);
+ mreq.imr_multiaddr.s_addr = in.sin_addr.s_addr;
+ mreq.imr_interface.s_addr = htonl(INADDR_ANY);
+ if(setsockopt(device_fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof mreq)) {
+ logger(LOG_ERR, "Cannot join multicast group %s %s: %s", host, port, sockstrerror(sockerrno));
+ closesocket(device_fd);
+ return false;
+ }
+ setsockopt(device_fd, IPPROTO_IP, IP_MULTICAST_LOOP, &one, sizeof one);
+ setsockopt(device_fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof ttl);
+ } break;
+
+ case AF_INET6: {
+ struct ipv6_mreq mreq;
+ struct sockaddr_in6 in6;
+ memcpy(&in6, ai->ai_addr, sizeof in6);
+ memcpy(&mreq.ipv6mr_multiaddr, &in6.sin6_addr, sizeof mreq.ipv6mr_multiaddr);
+ mreq.ipv6mr_interface = 0;
+ if(setsockopt(device_fd, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq, sizeof mreq)) {
+ logger(LOG_ERR, "Cannot join multicast group %s %s: %s", host, port, sockstrerror(sockerrno));
+ closesocket(device_fd);
+ return false;
+ }
+ setsockopt(device_fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &one, sizeof one);
+ setsockopt(device_fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof ttl);
+ } break;
+
+ default:
+ logger(LOG_ERR, "Multicast for address family %hx unsupported", ai->ai_family);
+ closesocket(device_fd);
+ return false;
+ }
+
+ logger(LOG_INFO, "%s is a %s", device, device_info);
+
+ return true;
+}
+
+static void close_device(void) {
+ close(device_fd);
+
+ free(device);
+ free(iface);
+
+ if(ai)
+ freeaddrinfo(ai);
+}
+
+static bool read_packet(vpn_packet_t *packet) {
+ int lenin;
+
+ if((lenin = recv(device_fd, packet->data, MTU, 0)) <= 0) {
+ logger(LOG_ERR, "Error while reading from %s %s: %s", device_info,
+ device, strerror(errno));
+ return false;
+ }
+
+ if(!memcmp(&ignore_src, packet->data + 6, sizeof ignore_src)) {
+ ifdebug(SCARY_THINGS) logger(LOG_DEBUG, "Ignoring loopback packet of %d bytes from %s", lenin, device_info);
+ packet->len = 0;
+ return true;
+ }
+
+ packet->len = lenin;
+
+ device_total_in += packet->len;
+
+ ifdebug(TRAFFIC) logger(LOG_DEBUG, "Read packet of %d bytes from %s", packet->len,
+ device_info);
+
+ return true;
+}
+
+static bool write_packet(vpn_packet_t *packet) {
+ ifdebug(TRAFFIC) logger(LOG_DEBUG, "Writing packet of %d bytes to %s",
+ packet->len, device_info);
+
+ if(sendto(device_fd, packet->data, packet->len, 0, ai->ai_addr, ai->ai_addrlen) < 0) {
+ logger(LOG_ERR, "Can't write to %s %s: %s", device_info, device,
+ strerror(errno));
+ return false;
+ }
+
+ device_total_out += packet->len;
+
+ memcpy(&ignore_src, packet->data + 6, sizeof ignore_src);
+
+ return true;
+}
+
+static void dump_device_stats(void) {
+ logger(LOG_DEBUG, "Statistics for %s %s:", device_info, device);
+ logger(LOG_DEBUG, " total bytes in: %10"PRIu64, device_total_in);
+ logger(LOG_DEBUG, " total bytes out: %10"PRIu64, device_total_out);
+}
+
+const devops_t multicast_devops = {
+ .setup = setup_device,
+ .close = close_device,
+ .read = read_packet,
+ .write = write_packet,
+ .dump_stats = dump_device_stats,
+};
+
+#if 0
+
+static bool not_supported(void) {
+ logger(LOG_ERR, "Raw socket device not supported on this platform");
+ return false;
+}
+
+const devops_t multicast_devops = {
+ .setup = not_supported,
+ .close = NULL,
+ .read = NULL,
+ .write = NULL,
+ .dump_stats = NULL,
+};
+#endif
projects / oweals / tinc.git / commitdiff