X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fmulticast_device.c;fp=src%2Fmulticast_device.c;h=392fd3713e03fd33232404fe81e186ae43f60044;hp=0000000000000000000000000000000000000000;hb=c373de2e9812700c0568640727ad917b6fc7d758;hpb=a7dbb50c23f447a23b543c92ec096ff178bc2de3 diff --git a/src/multicast_device.c b/src/multicast_device.c new file mode 100644 index 00000000..392fd371 --- /dev/null +++ b/src/multicast_device.c @@ -0,0 +1,216 @@ +/* + device.c -- multicast socket + Copyright (C) 2002-2005 Ivo Timmermans, + 2002-2012 Guus Sliepen + + 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