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 1.1.2.13 2003/06/11 19:28:37 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 /*
  60   open the local ethertap device
  61 */
  62 int setup_device(void)
  63 {
  64         cp();
  65
  66         if(!get_config_string(lookup_config(config_tree, "Device"), &device))
  67                 device = DEFAULT_DEVICE;
  68
  69         if(!get_config_string(lookup_config(config_tree, "Interface"), &interface))
  70                 interface = rindex(device, '/') ? rindex(device, '/') + 1 : device;
  71         if((device_fd = open(device, O_RDWR | O_NONBLOCK)) < 0) {
  72                 syslog(LOG_ERR, _("Could not open %s: %s"), device, strerror(errno));
  73                 return -1;
  74         }
  75
  76         device_info = _("OpenBSD tun device");
  77
  78         syslog(LOG_INFO, _("%s is a %s"), device, device_info);
  79
  80         return 0;
  81 }
  82
  83 void close_device(void)
  84 {
  85         cp();
  86
  87         close(device_fd);
  88 }
  89
  90 int read_packet(vpn_packet_t *packet)
  91 {
  92         int lenin;
  93         u_int32_t type;
  94         struct iovec vector[2] = {{&type, sizeof(type)}, {packet->data + 14, MTU - 14}};
  95
  96         cp();
  97
  98         if((lenin = readv(device_fd, vector, 2)) <= 0) {
  99                 syslog(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 100                            device, strerror(errno));
 101                 return -1;
 102         }
 103
 104         switch (ntohl(type)) {
 105                 case AF_INET:
 106                         packet->data[12] = 0x8;
 107                         packet->data[13] = 0x0;
 108                         break;
 109
 110                 case AF_INET6:
 111                         packet->data[12] = 0x86;
 112                         packet->data[13] = 0xDD;
 113                         break;
 114
 115                 default:
 116                         if(debug_lvl >= DEBUG_TRAFFIC)
 117                                 syslog(LOG_ERR,
 118                                            _
 119                                            ("Unknown address family %d while reading packet from %s %s"),
 120                                            ntohl(type), device_info, device);
 121                         return -1;
 122         }
 123
 124         packet->len = lenin + 10;
 125
 126         device_total_in += packet->len;
 127
 128         if(debug_lvl >= DEBUG_TRAFFIC) {
 129                 syslog(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
 130                            device_info);
 131         }
 132
 133         return 0;
 134 }
 135
 136 int write_packet(vpn_packet_t *packet)
 137 {
 138         u_int32_t type;
 139         struct iovec vector[2];
 140         int af;
 141
 142         cp();
 143
 144         if(debug_lvl >= DEBUG_TRAFFIC)
 145                 syslog(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
 146                            packet->len, device_info);
 147
 148         af = (packet->data[12] << 8) + packet->data[13];
 149
 150         switch (af) {
 151         case 0x800:
 152                 type = htonl(AF_INET);
 153                 break;
 154         case 0x86DD:
 155                 type = htonl(AF_INET6);
 156                 break;
 157         default:
 158                 if(debug_lvl >= DEBUG_TRAFFIC)
 159                         syslog(LOG_ERR,
 160                                    _("Unknown address family %d while writing packet to %s %s"),
 161                                    af, device_info, device);
 162                 return -1;
 163         }
 164
 165         vector[0].iov_base = &type;
 166         vector[0].iov_len = sizeof(type);
 167         vector[1].iov_base = packet->data + 14;
 168         vector[1].iov_len = packet->len - 14;
 169
 170         if(writev(device_fd, vector, 2) < 0) {
 171                 syslog(LOG_ERR, _("Can't write to %s %s: %s"), device_info, device,
 172                            strerror(errno));
 173                 return -1;
 174         }
 175
 176         device_total_out += packet->len;
 177 }
 178
 179 void dump_device_stats(void)
 180 {
 181         cp();
 182
 183         syslog(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
 184         syslog(LOG_DEBUG, _(" total bytes in:  %10d"), device_total_in);
 185         syslog(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);
 186 }