gvpe/src/device-linux.C

/*
    device-linux.C -- Interaction with Linux tun/tap device
    Copyright (C) 2003 Marc Lehmann <pcg@goof.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

#include "config.h"

#include <cstdio>
#include <cstring>
#include <cstdlib>

#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <net/if.h>
#include <unistd.h>
#include <sys/ioctl.h>

#include <net/if.h>

#ifdef LINUX_IF_TUN_H
# include LINUX_IF_TUN_H
#else
#include <linux/if_tun.h>
#endif
#define DEFAULT_DEVICE "/dev/net/tun"

#include "gettext.h"

#include "conf.h"

#if TEST_ETHEREMU
# include "ether_emu.C"
#endif

const char *
tap_device::info ()
{
  return _("Linux tun/tap device");
}

tap_device::tap_device ()
{
  struct ifreq ifr;

  device = DEFAULT_DEVICE;

  fd = open (device, O_RDWR);

  if (fd < 0)
    {
      slog (L_ERR, _("could not open device %s: %s"), device, strerror (errno));
      exit (1);
    }

  memset (&ifr, 0, sizeof (ifr));
#if TEST_ETHEREMU
  ifr.ifr_flags = IFF_TUN | IFF_NO_PI;
#else
  ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
#endif

  if (conf.ifname)
    strncpy (ifr.ifr_name, conf.ifname, IFNAMSIZ);
  else
    ifr.ifr_name[0] = 0;

  if (!ioctl (fd, TUNSETIFF, &ifr))
    {
      strncpy (ifrname, ifr.ifr_name, IFNAMSIZ);
      ifrname [IFNAMSIZ] = 0;
    }
  else
    {
      slog (L_CRIT, _("unable to configure tun/tap interface: %s"), strerror (errno));
      exit (1);
    }

  if (ioctl (fd, TUNSETPERSIST, conf.ifpersist ? 1 : 0))
    slog (L_WARN, _("cannot set persistency mode for device %s: %s"), ifrname, strerror (errno));

  slog (L_DEBUG, _("%s is a %s"), device, info ());
}

tap_device::~tap_device ()
{
  close (fd);
}

tap_packet *
tap_device::recv ()
{
  tap_packet *pkt = new tap_packet;

#if TEST_ETHEREMU
  pkt->len = read (fd, &((*pkt)[14]), MAX_MTU - 14);
#else
  pkt->len = read (fd, &((*pkt)[0]), MAX_MTU);
#endif

  if (pkt->len <= 0)
    {
      delete pkt;
      slog (L_ERR, _("error while reading from %s %s: %s"),
            info (), DEFAULT_DEVICE, strerror (errno));
      return 0;
    }

#if TEST_ETHEREMU
  pkt->len += 14;

  // assume ipv4
  (*pkt)[12] = 0x08;
  (*pkt)[13] = 0x00;

  if (!ether_emu.tun_to_tap (pkt))
    {
      delete pkt;
      return 0;
    }
#endif

  return pkt;
}

void
tap_device::send (tap_packet *pkt)
{
#if TEST_ETHEREMU
  if (ether_emu.tap_to_tun (pkt) &&
      write (fd, &((*pkt)[14]), pkt->len - 14) < 0)
#else
  if (write (fd, &((*pkt)[0]), pkt->len) < 0)
#endif
    slog (L_ERR, _("can't write to %s %s: %s"), info (), DEFAULT_DEVICE,
          strerror (errno));
}

Revision:	1.5
Committed:	Thu Oct 16 02:41:21 2003 UTC (20 years, 7 months ago) by pcg
Content type:	text/plain
Branch:	MAIN
Changes since 1.4:	+1 -0 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	pcg	1.1	/*
2			device-linux.C -- Interaction with Linux tun/tap device
3	pcg	1.5	Copyright (C) 2003 Marc Lehmann <pcg@goof.com>
4	pcg	1.1
5			This program is free software; you can redistribute it and/or modify
6			it under the terms of the GNU General Public License as published by
7			the Free Software Foundation; either version 2 of the License, or
8			(at your option) any later version.
9
10			This program is distributed in the hope that it will be useful,
11			but WITHOUT ANY WARRANTY; without even the implied warranty of
12			MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13			GNU General Public License for more details.
14
15			You should have received a copy of the GNU General Public License
16			along with this program; if not, write to the Free Software
17			Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18			*/
19
20			#include "config.h"
21
22			#include <cstdio>
23			#include <cstring>
24			#include <cstdlib>
25
26			#include <errno.h>
27			#include <sys/types.h>
28			#include <sys/stat.h>
29			#include <fcntl.h>
30			#include <net/if.h>
31			#include <unistd.h>
32			#include <sys/ioctl.h>
33
34	pcg	1.3	#include <net/if.h>
35
36	pcg	1.1	#ifdef LINUX_IF_TUN_H
37	pcg	1.3	# include LINUX_IF_TUN_H
38	pcg	1.1	#else
39			#include <linux/if_tun.h>
40			#endif
41			#define DEFAULT_DEVICE "/dev/net/tun"
42
43			#include "gettext.h"
44
45			#include "conf.h"
46
47	pcg	1.4	#if TEST_ETHEREMU
48			# include "ether_emu.C"
49			#endif
50
51	pcg	1.3	const char *
52			tap_device::info ()
53			{
54			return _("Linux tun/tap device");
55			}
56
57	pcg	1.1	tap_device::tap_device ()
58			{
59			struct ifreq ifr;
60
61			device = DEFAULT_DEVICE;
62
63			fd = open (device, O_RDWR);
64
65			if (fd < 0)
66			{
67			slog (L_ERR, _("could not open device %s: %s"), device, strerror (errno));
68			exit (1);
69			}
70
71			memset (&ifr, 0, sizeof (ifr));
72	pcg	1.4	#if TEST_ETHEREMU
73			ifr.ifr_flags = IFF_TUN \| IFF_NO_PI;
74			#else
75	pcg	1.1	ifr.ifr_flags = IFF_TAP \| IFF_NO_PI;
76	pcg	1.4	#endif
77	pcg	1.1
78			if (conf.ifname)
79			strncpy (ifr.ifr_name, conf.ifname, IFNAMSIZ);
80			else
81			ifr.ifr_name[0] = 0;
82
83			if (!ioctl (fd, TUNSETIFF, &ifr))
84			{
85			strncpy (ifrname, ifr.ifr_name, IFNAMSIZ);
86			ifrname [IFNAMSIZ] = 0;
87			}
88			else
89			{
90			slog (L_CRIT, _("unable to configure tun/tap interface: %s"), strerror (errno));
91			exit (1);
92			}
93
94	pcg	1.2	if (ioctl (fd, TUNSETPERSIST, conf.ifpersist ? 1 : 0))
95			slog (L_WARN, _("cannot set persistency mode for device %s: %s"), ifrname, strerror (errno));
96	pcg	1.1
97			slog (L_DEBUG, _("%s is a %s"), device, info ());
98			}
99
100			tap_device::~tap_device ()
101			{
102			close (fd);
103			}
104
105			tap_packet *
106			tap_device::recv ()
107			{
108			tap_packet *pkt = new tap_packet;
109
110	pcg	1.4	#if TEST_ETHEREMU
111			pkt->len = read (fd, &((*pkt)[14]), MAX_MTU - 14);
112			#else
113	pcg	1.1	pkt->len = read (fd, &((*pkt)[0]), MAX_MTU);
114	pcg	1.4	#endif
115	pcg	1.1
116			if (pkt->len <= 0)
117			{
118	pcg	1.3	delete pkt;
119	pcg	1.1	slog (L_ERR, _("error while reading from %s %s: %s"),
120			info (), DEFAULT_DEVICE, strerror (errno));
121			return 0;
122			}
123
124	pcg	1.4	#if TEST_ETHEREMU
125			pkt->len += 14;
126
127			// assume ipv4
128			(*pkt)[12] = 0x08;
129			(*pkt)[13] = 0x00;
130
131			if (!ether_emu.tun_to_tap (pkt))
132			{
133			delete pkt;
134			return 0;
135			}
136			#endif
137
138	pcg	1.1	return pkt;
139			}
140
141			void
142			tap_device::send (tap_packet *pkt)
143			{
144	pcg	1.4	#if TEST_ETHEREMU
145			if (ether_emu.tap_to_tun (pkt) &&
146			write (fd, &((*pkt)[14]), pkt->len - 14) < 0)
147			#else
148	pcg	1.1	if (write (fd, &((*pkt)[0]), pkt->len) < 0)
149	pcg	1.4	#endif
150	pcg	1.1	slog (L_ERR, _("can't write to %s %s: %s"), info (), DEFAULT_DEVICE,
151			strerror (errno));
152			}
153