tinc-vpn.org Git - tinc/blob - src/uml_socket/device.c

   1 /*
   2     device.c -- UML network socket
   3     Copyright (C) 2002-2005 Ivo Timmermans,
   4                   2002-2009 Guus Sliepen <guus@tinc-vpn.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 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.
  19 */
  20
  21 #include "system.h"
  22
  23 #include <sys/un.h>
  24
  25 #include "conf.h"
  26 #include "net.h"
  27 #include "logger.h"
  28 #include "utils.h"
  29 #include "route.h"
  30
  31 int device_fd = -1;
  32 static int listen_fd = -1;
  33 static int request_fd = -1;
  34 static int data_fd = -1;
  35 static int write_fd = -1;
  36 static int state = 0;
  37 char *device = NULL;
  38 char *iface = NULL;
  39 static char *device_info;
  40
  41 extern char *identname;
  42 extern bool running;
  43
  44 static int device_total_in = 0;
  45 static int device_total_out = 0;
  46
  47 enum request_type { REQ_NEW_CONTROL };
  48
  49 static struct request {
  50   uint32_t magic;
  51   uint32_t version;
  52   enum request_type type;
  53   struct sockaddr_un sock;
  54 } request;
  55
  56 static struct sockaddr_un data_sun;
  57
  58 bool setup_device(void) {
  59         struct sockaddr_un listen_sun;
  60         static const int one = 1;
  61         struct {
  62                 char zero;
  63                 int pid;
  64                 int usecs;
  65         } name;
  66         struct timeval tv;
  67
  68         cp();
  69
  70         if(!get_config_string(lookup_config(config_tree, "Device"), &device))
  71                 xasprintf(&device, LOCALSTATEDIR "/run/%s.umlsocket", identname);
  72
  73         get_config_string(lookup_config(config_tree, "Interface"), &iface);
  74
  75         device_info = _("UML network socket");
  76
  77         if((write_fd = socket(PF_UNIX, SOCK_DGRAM, 0)) < 0) {
  78                 logger(LOG_ERR, _("Could not open write %s: %s"), device_info, strerror(errno));
  79                 running = false;
  80                 return false;
  81         }
  82
  83         setsockopt(write_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof one);
  84
  85         if(fcntl(write_fd, F_SETFL, O_NONBLOCK) < 0) {
  86                 logger(LOG_ERR, _("System call `%s' failed: %s"), "fcntl", strerror(errno));
  87                 running = false;
  88                 return false;
  89         }
  90
  91         if((data_fd = socket(PF_UNIX, SOCK_DGRAM, 0)) < 0) {
  92                 logger(LOG_ERR, _("Could not open data %s: %s"), device_info, strerror(errno));
  93                 running = false;
  94                 return false;
  95         }
  96
  97         setsockopt(data_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof one);
  98
  99         if(fcntl(data_fd, F_SETFL, O_NONBLOCK) < 0) {
 100                 logger(LOG_ERR, _("System call `%s' failed: %s"), "fcntl", strerror(errno));
 101                 running = false;
 102                 return false;
 103         }
 104
 105         name.zero = 0;
 106         name.pid = getpid();
 107         gettimeofday(&tv, NULL);
 108         name.usecs = tv.tv_usec;
 109         data_sun.sun_family = AF_UNIX;
 110         memcpy(&data_sun.sun_path, &name, sizeof name);
 111
 112         if(bind(data_fd, (struct sockaddr *)&data_sun, sizeof data_sun) < 0) {
 113                 logger(LOG_ERR, _("Could not bind data %s: %s"), device_info, strerror(errno));
 114                 running = false;
 115                 return false;
 116         }
 117
 118         if((listen_fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
 119                 logger(LOG_ERR, _("Could not open %s: %s"), device_info,
 120                            strerror(errno));
 121                 return false;
 122         }
 123
 124         setsockopt(listen_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof one);
 125
 126         if(fcntl(listen_fd, F_SETFL, O_NONBLOCK) < 0) {
 127                 logger(LOG_ERR, _("System call `%s' failed: %s"), "fcntl", strerror(errno));
 128                 return false;
 129         }
 130
 131         listen_sun.sun_family = AF_UNIX;
 132         strncpy(listen_sun.sun_path, device, sizeof listen_sun.sun_path);
 133         if(bind(listen_fd, (struct sockaddr *)&listen_sun, sizeof listen_sun) < 0) {
 134                 logger(LOG_ERR, _("Could not bind %s to %s: %s"), device_info, device, strerror(errno));
 135                 return false;
 136         }
 137
 138         if(listen(listen_fd, 1) < 0) {
 139                 logger(LOG_ERR, _("Could not listen on %s %s: %s"), device_info, device, strerror(errno));
 140                 return false;
 141         }
 142
 143         device_fd = listen_fd;
 144         state = 0;
 145
 146         logger(LOG_INFO, _("%s is a %s"), device, device_info);
 147
 148         if(routing_mode == RMODE_ROUTER)
 149                 overwrite_mac = true;
 150
 151         return true;
 152 }
 153
 154 void close_device(void) {
 155         cp();
 156
 157         if(listen_fd >= 0)
 158                 close(listen_fd);
 159
 160         if(request_fd >= 0)
 161                 close(request_fd);
 162
 163         if(data_fd >= 0)
 164                 close(data_fd);
 165
 166         if(write_fd >= 0)
 167                 close(write_fd);
 168
 169         unlink(device);
 170
 171         free(device);
 172         if(iface) free(iface);
 173 }
 174
 175 bool read_packet(vpn_packet_t *packet) {
 176         int lenin;
 177
 178         cp();
 179
 180         switch(state) {
 181                 case 0: {
 182                         struct sockaddr sa;
 183                         int salen = sizeof sa;
 184
 185                         request_fd = accept(listen_fd, &sa, &salen);
 186                         if(request_fd < 0) {
 187                                 logger(LOG_ERR, _("Could not accept connection to %s %s: %s"), device_info, device, strerror(errno));
 188                                 return false;
 189                         }
 190
 191                         if(fcntl(listen_fd, F_SETFL, O_NONBLOCK) < 0) {
 192                                 logger(LOG_ERR, _("System call `%s' failed: %s"), "fcntl", strerror(errno));
 193                                 running = false;
 194                                 return false;
 195                         }
 196
 197                         close(listen_fd);
 198                         listen_fd = -1;
 199                         device_fd = request_fd;
 200                         state = 1;
 201
 202                         return false;
 203                 }
 204
 205                 case 1: {
 206                         if((lenin = read(request_fd, &request, sizeof request)) != sizeof request) {
 207                                 logger(LOG_ERR, _("Error while reading request from %s %s: %s"), device_info,
 208                                            device, strerror(errno));
 209                                 running = false;
 210                                 return false;
 211                         }
 212
 213                         if(request.magic != 0xfeedface || request.version != 3 || request.type != REQ_NEW_CONTROL) {
 214                                 logger(LOG_ERR, _("Unknown magic %x, version %d, request type %d from %s %s"),
 215                                                 request.magic, request.version, request.type, device_info, device);
 216                                 running = false;
 217                                 return false;
 218                         }
 219
 220                         if(connect(write_fd, &request.sock, sizeof request.sock) < 0) {
 221                                 logger(LOG_ERR, _("Could not bind write %s: %s"), device_info, strerror(errno));
 222                                 running = false;
 223                                 return false;
 224                         }
 225
 226                         write(request_fd, &data_sun, sizeof data_sun);
 227                         device_fd = data_fd;
 228
 229                         logger(LOG_INFO, _("Connection with UML established"));
 230
 231                         state = 2;
 232                         return false;
 233                 }
 234
 235                 case 2: {
 236                         if((lenin = read(data_fd, packet->data, MTU)) <= 0) {
 237                                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 238                                            device, strerror(errno));
 239                                 running = false;
 240                                 return false;
 241                         }
 242
 243                         packet->len = lenin;
 244
 245                         device_total_in += packet->len;
 246
 247                         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
 248                                            device_info);
 249
 250                         return true;
 251                 }
 252         }
 253 }
 254
 255 bool write_packet(vpn_packet_t *packet) {
 256         cp();
 257
 258         if(state != 2) {
 259                 ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Dropping packet of %d bytes to %s: not connected to UML yet"),
 260                                 packet->len, device_info);
 261                 return false;
 262         }
 263
 264         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
 265                            packet->len, device_info);
 266
 267         if(write(write_fd, packet->data, packet->len) < 0) {
 268                 if(errno != EINTR && errno != EAGAIN) {
 269                         logger(LOG_ERR, _("Can't write to %s %s: %s"), device_info, device, strerror(errno));
 270                         running = false;
 271                 }
 272
 273                 return false;
 274         }
 275
 276         device_total_out += packet->len;
 277
 278         return true;
 279 }
 280
 281 void dump_device_stats(void) {
 282         cp();
 283
 284         logger(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
 285         logger(LOG_DEBUG, _(" total bytes in:  %10d"), device_total_in);
 286         logger(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);
 287 }