www.tinc-vpn.org Git - tinc/blob - src/openbsd/device.c

   1 /*
   2     device.c -- Interaction with OpenBSD tun device
   3     Copyright (C) 2001-2002 Ivo Timmermans <ivo@o2w.nl>,
   4                   2001-2002 Guus Sliepen <guus@sliepen.eu.org>
   5
   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.
  10
  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.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19
  20     $Id: device.c,v 1.1.2.12 2002/09/10 21:29:42 guus Exp $
  21 */
  22
  23 #include "config.h"
  24
  25 #include <stdio.h>
  26 #include <errno.h>
  27 #include <sys/types.h>
  28 #include <sys/uio.h>
  29 #include <sys/stat.h>
  30 #include <sys/ioctl.h>
  31 #include <sys/socket.h>
  32 #include <fcntl.h>
  33 #include <net/if.h>
  34 #include <unistd.h>
  35 #include <syslog.h>
  36 #include <string.h>
  37
  38 #include <utils.h>
  39 #include "conf.h"
  40 #include "net.h"
  41 #include "subnet.h"
  42
  43 #include "system.h"
  44
  45 #define DEFAULT_DEVICE "/dev/tun0"
  46
  47 #define DEVICE_TYPE_ETHERTAP 0
  48 #define DEVICE_TYPE_TUNTAP 1
  49
  50 int device_fd = -1;
  51 int device_type;
  52 char *device;
  53 char *interface;
  54 char *device_info;
  55
  56 int device_total_in = 0;
  57 int device_total_out = 0;
  58
  59 extern subnet_t mymac;
  60
  61 /*
  62   open the local ethertap device
  63 */
  64 int setup_device(void)
  65 {
  66         cp();
  67
  68         if(!get_config_string(lookup_config(config_tree, "Device"), &device))
  69                 device = DEFAULT_DEVICE;
  70
  71         if(!get_config_string(lookup_config(config_tree, "Interface"), &interface))
  72                 interface = rindex(device, '/') ? rindex(device, '/') + 1 : device;
  73         if((device_fd = open(device, O_RDWR | O_NONBLOCK)) < 0) {
  74                 syslog(LOG_ERR, _("Could not open %s: %s"), device, strerror(errno));
  75                 return -1;
  76         }
  77
  78         /* Set default MAC address for ethertap devices */
  79         mymac.type = SUBNET_MAC;
  80         mymac.net.mac.address.x[0] = 0xfe;
  81         mymac.net.mac.address.x[1] = 0xfd;
  82         mymac.net.mac.address.x[2] = 0x00;
  83         mymac.net.mac.address.x[3] = 0x00;
  84         mymac.net.mac.address.x[4] = 0x00;
  85         mymac.net.mac.address.x[5] = 0x00;
  86
  87         device_info = _("OpenBSD tun device");
  88
  89         syslog(LOG_INFO, _("%s is a %s"), device, device_info);
  90
  91         return 0;
  92 }
  93
  94 void close_device(void)
  95 {
  96         cp();
  97
  98         close(device_fd);
  99 }
 100
 101 int read_packet(vpn_packet_t *packet)
 102 {
 103         int lenin;
 104         u_int32_t type;
 105         struct iovec vector[2] = {{&type, sizeof(type)}, {packet->data + 14, MTU - 14}};
 106
 107         cp();
 108
 109         if((lenin = readv(device_fd, vector, 2)) <= 0) {
 110                 syslog(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 111                            device, strerror(errno));
 112                 return -1;
 113         }
 114
 115         memcpy(packet->data, mymac.net.mac.address.x, 6);
 116         memcpy(packet->data + 6, mymac.net.mac.address.x, 6);
 117
 118         switch (ntohl(type)) {
 119                 case AF_INET:
 120                         packet->data[12] = 0x8;
 121                         packet->data[13] = 0x0;
 122                         break;
 123
 124                 case AF_INET6:
 125                         packet->data[12] = 0x86;
 126                         packet->data[13] = 0xDD;
 127                         break;
 128
 129                 default:
 130                         if(debug_lvl >= DEBUG_TRAFFIC)
 131                                 syslog(LOG_ERR,
 132                                            _
 133                                            ("Unknown address family %d while reading packet from %s %s"),
 134                                            ntohl(type), device_info, device);
 135                         return -1;
 136         }
 137
 138         packet->len = lenin + 10;
 139
 140         device_total_in += packet->len;
 141
 142         if(debug_lvl >= DEBUG_TRAFFIC) {
 143                 syslog(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
 144                            device_info);
 145         }
 146
 147         return 0;
 148 }
 149
 150 int write_packet(vpn_packet_t *packet)
 151 {
 152         u_int32_t type;
 153         struct iovec vector[2];
 154         int af;
 155
 156         cp();
 157
 158         if(debug_lvl >= DEBUG_TRAFFIC)
 159                 syslog(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
 160                            packet->len, device_info);
 161
 162         af = (packet->data[12] << 8) + packet->data[13];
 163
 164         switch (af) {
 165         case 0x800:
 166                 type = htonl(AF_INET);
 167                 break;
 168         case 0x86DD:
 169                 type = htonl(AF_INET6);
 170                 break;
 171         default:
 172                 if(debug_lvl >= DEBUG_TRAFFIC)
 173                         syslog(LOG_ERR,
 174                                    _("Unknown address family %d while writing packet to %s %s"),
 175                                    af, device_info, device);
 176                 return -1;
 177         }
 178
 179         vector[0].iov_base = &type;
 180         vector[0].iov_len = sizeof(type);
 181         vector[1].iov_base = packet->data + 14;
 182         vector[1].iov_len = packet->len - 14;
 183
 184         if(writev(device_fd, vector, 2) < 0) {
 185                 syslog(LOG_ERR, _("Can't write to %s %s: %s"), device_info, device,
 186                            strerror(errno));
 187                 return -1;
 188         }
 189
 190         device_total_out += packet->len;
 191 }
 192
 193 void dump_device_stats(void)
 194 {
 195         cp();
 196
 197         syslog(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
 198         syslog(LOG_DEBUG, _(" total bytes in:  %10d"), device_total_in);
 199         syslog(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);
 200 }