www.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
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, 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 {
  60         struct sockaddr_un listen_sun;
  61         static const int one = 1;
  62         struct {
  63                 char zero;
  64                 int pid;
  65                 int usecs;
  66         } name;
  67         struct timeval tv;
  68
  69         cp();
  70
  71         if(!get_config_string(lookup_config(config_tree, "Device"), &device))
  72                 xasprintf(&device, LOCALSTATEDIR "/run/%s.umlsocket", identname);
  73
  74         get_config_string(lookup_config(config_tree, "Interface"), &iface);
  75
  76         device_info = _("UML network socket");
  77
  78         if((write_fd = socket(PF_UNIX, SOCK_DGRAM, 0)) < 0) {
  79                 logger(LOG_ERR, _("Could not open write %s: %s"), device_info, strerror(errno));
  80                 running = false;
  81                 return false;
  82         }
  83
  84         setsockopt(write_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof one);
  85
  86         if(fcntl(write_fd, F_SETFL, O_NONBLOCK) < 0) {
  87                 logger(LOG_ERR, _("System call `%s' failed: %s"), "fcntl", strerror(errno));
  88                 running = false;
  89                 return false;
  90         }
  91
  92         if((data_fd = socket(PF_UNIX, SOCK_DGRAM, 0)) < 0) {
  93                 logger(LOG_ERR, _("Could not open data %s: %s"), device_info, strerror(errno));
  94                 running = false;
  95                 return false;
  96         }
  97
  98         setsockopt(data_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof one);
  99
 100         if(fcntl(data_fd, F_SETFL, O_NONBLOCK) < 0) {
 101                 logger(LOG_ERR, _("System call `%s' failed: %s"), "fcntl", strerror(errno));
 102                 running = false;
 103                 return false;
 104         }
 105
 106         name.zero = 0;
 107         name.pid = getpid();
 108         gettimeofday(&tv, NULL);
 109         name.usecs = tv.tv_usec;
 110         data_sun.sun_family = AF_UNIX;
 111         memcpy(&data_sun.sun_path, &name, sizeof name);
 112
 113         if(bind(data_fd, (struct sockaddr *)&data_sun, sizeof data_sun) < 0) {
 114                 logger(LOG_ERR, _("Could not bind data %s: %s"), device_info, strerror(errno));
 115                 running = false;
 116                 return false;
 117         }
 118
 119         if((listen_fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
 120                 logger(LOG_ERR, _("Could not open %s: %s"), device_info,
 121                            strerror(errno));
 122                 return false;
 123         }
 124
 125         setsockopt(listen_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof one);
 126
 127         if(fcntl(listen_fd, F_SETFL, O_NONBLOCK) < 0) {
 128                 logger(LOG_ERR, _("System call `%s' failed: %s"), "fcntl", strerror(errno));
 129                 return false;
 130         }
 131
 132         listen_sun.sun_family = AF_UNIX;
 133         strncpy(listen_sun.sun_path, device, sizeof listen_sun.sun_path);
 134         if(bind(listen_fd, (struct sockaddr *)&listen_sun, sizeof listen_sun) < 0) {
 135                 logger(LOG_ERR, _("Could not bind %s to %s: %s"), device_info, device, strerror(errno));
 136                 return false;
 137         }
 138
 139         if(listen(listen_fd, 1) < 0) {
 140                 logger(LOG_ERR, _("Could not listen on %s %s: %s"), device_info, device, strerror(errno));
 141                 return false;
 142         }
 143
 144         device_fd = listen_fd;
 145         state = 0;
 146
 147         logger(LOG_INFO, _("%s is a %s"), device, device_info);
 148
 149         if(routing_mode == RMODE_ROUTER)
 150                 overwrite_mac = true;
 151
 152         return true;
 153 }
 154
 155 void close_device(void)
 156 {
 157         cp();
 158
 159         if(listen_fd >= 0)
 160                 close(listen_fd);
 161
 162         if(request_fd >= 0)
 163                 close(request_fd);
 164
 165         if(data_fd >= 0)
 166                 close(data_fd);
 167
 168         if(write_fd >= 0)
 169                 close(write_fd);
 170
 171         unlink(device);
 172
 173         free(device);
 174         if(iface) free(iface);
 175 }
 176
 177 bool read_packet(vpn_packet_t *packet)
 178 {
 179         int lenin;
 180
 181         cp();
 182
 183         switch(state) {
 184                 case 0: {
 185                         struct sockaddr sa;
 186                         int salen = sizeof sa;
 187
 188                         request_fd = accept(listen_fd, &sa, &salen);
 189                         if(request_fd < 0) {
 190                                 logger(LOG_ERR, _("Could not accept connection to %s %s: %s"), device_info, device, strerror(errno));
 191                                 return false;
 192                         }
 193
 194                         if(fcntl(listen_fd, F_SETFL, O_NONBLOCK) < 0) {
 195                                 logger(LOG_ERR, _("System call `%s' failed: %s"), "fcntl", strerror(errno));
 196                                 running = false;
 197                                 return false;
 198                         }
 199
 200                         close(listen_fd);
 201                         listen_fd = -1;
 202                         device_fd = request_fd;
 203                         state = 1;
 204
 205                         return false;
 206                 }
 207
 208                 case 1: {
 209                         if((lenin = read(request_fd, &request, sizeof request)) != sizeof request) {
 210                                 logger(LOG_ERR, _("Error while reading request from %s %s: %s"), device_info,
 211                                            device, strerror(errno));
 212                                 running = false;
 213                                 return false;
 214                         }
 215
 216                         if(request.magic != 0xfeedface || request.version != 3 || request.type != REQ_NEW_CONTROL) {
 217                                 logger(LOG_ERR, _("Unknown magic %x, version %d, request type %d from %s %s"),
 218                                                 request.magic, request.version, request.type, device_info, device);
 219                                 running = false;
 220                                 return false;
 221                         }
 222
 223                         if(connect(write_fd, &request.sock, sizeof request.sock) < 0) {
 224                                 logger(LOG_ERR, _("Could not bind write %s: %s"), device_info, strerror(errno));
 225                                 running = false;
 226                                 return false;
 227                         }
 228
 229                         write(request_fd, &data_sun, sizeof data_sun);
 230                         device_fd = data_fd;
 231
 232                         logger(LOG_INFO, _("Connection with UML established"));
 233
 234                         state = 2;
 235                         return false;
 236                 }
 237
 238                 case 2: {
 239                         if((lenin = read(data_fd, packet->data, MTU)) <= 0) {
 240                                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 241                                            device, strerror(errno));
 242                                 running = false;
 243                                 return false;
 244                         }
 245
 246                         packet->len = lenin;
 247
 248                         device_total_in += packet->len;
 249
 250                         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
 251                                            device_info);
 252
 253                         return true;
 254                 }
 255         }
 256 }
 257
 258 bool write_packet(vpn_packet_t *packet)
 259 {
 260         cp();
 261
 262         if(state != 2) {
 263                 ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Dropping packet of %d bytes to %s: not connected to UML yet"),
 264                                 packet->len, device_info);
 265                 return false;
 266         }
 267
 268         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
 269                            packet->len, device_info);
 270
 271         if(write(write_fd, packet->data, packet->len) < 0) {
 272                 if(errno != EINTR && errno != EAGAIN) {
 273                         logger(LOG_ERR, _("Can't write to %s %s: %s"), device_info, device, strerror(errno));
 274                         running = false;
 275                 }
 276
 277                 return false;
 278         }
 279
 280         device_total_out += packet->len;
 281
 282         return true;
 283 }
 284
 285 void dump_device_stats(void)
 286 {
 287         cp();
 288
 289         logger(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
 290         logger(LOG_DEBUG, _(" total bytes in:  %10d"), device_total_in);
 291         logger(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);
 292 }