vde/tuntap.c

   1 /* Copyright 2002 Yon Uriarte and Jeff Dike
   2  * Licensed under the GPL
   3  * This file is part of the original uml_switch code
   4  * Modified 2003 Renzo Davoli
   5  */
   6
   7 #include <config.h>
   8 #include <stdio.h>
   9 #include <fcntl.h>
  10 #include <errno.h>
  11 #include <string.h>
  12 #include <unistd.h>
  13 #include <syslog.h>
  14 #include <sys/ioctl.h>
  15 #include <net/if.h>
  16 #include <linux/if_tun.h>
  17
  18 #include <port.h>
  19 #include <switch.h>
  20
  21 void send_tap(int fd, void *packet, int len, void *unused)
  22 {
  23   int n;
  24
  25   n = write(fd, packet, len);
  26   if(n != len){
  27     if(errno != EAGAIN) printlog(LOG_WARNING,"send_tap %s",strerror(errno));
  28   }
  29 }
  30
  31 int open_tap(char *dev)
  32 {
  33   struct ifreq ifr;
  34   int fd;
  35
  36   if((fd = open("/dev/net/tun", O_RDWR)) < 0){
  37     printlog(LOG_ERR,"Failed to open /dev/net/tun %s",strerror(errno));
  38     return(-1);
  39   }
  40   memset(&ifr, 0, sizeof(ifr));
  41   ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
  42   strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name) - 1);
  43   /*printf("dev=\"%s\", ifr.ifr_name=\"%s\"\n", ifr.ifr_name, dev);*/
  44   if(ioctl(fd, TUNSETIFF, (void *) &ifr) < 0){
  45     printlog(LOG_ERR,"TUNSETIFF failed %s",strerror(errno));
  46     close(fd);
  47     return(-1);
  48   }
  49   return(fd);
  50 }