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
# define IF_istun
# 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:	1.6
Committed:	Thu Oct 16 13:37:10 2003 UTC (20 years, 7 months ago) by pcg
Content type:	text/plain
Branch:	MAIN
CVS Tags:	poll-based-iom, VPE_1_2
Changes since 1.5:	+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	pcg	1.6	# define IF_istun
49	pcg	1.4	# include "ether_emu.C"
50			#endif
51
52	pcg	1.3	const char *
53			tap_device::info ()
54			{
55			return _("Linux tun/tap device");
56			}
57
58	pcg	1.1	tap_device::tap_device ()
59			{
60			struct ifreq ifr;
61
62			device = DEFAULT_DEVICE;
63
64			fd = open (device, O_RDWR);
65
66			if (fd < 0)
67			{
68			slog (L_ERR, _("could not open device %s: %s"), device, strerror (errno));
69			exit (1);
70			}
71
72			memset (&ifr, 0, sizeof (ifr));
73	pcg	1.4	#if TEST_ETHEREMU
74			ifr.ifr_flags = IFF_TUN \| IFF_NO_PI;
75			#else
76	pcg	1.1	ifr.ifr_flags = IFF_TAP \| IFF_NO_PI;
77	pcg	1.4	#endif
78	pcg	1.1
79			if (conf.ifname)
80			strncpy (ifr.ifr_name, conf.ifname, IFNAMSIZ);
81			else
82			ifr.ifr_name[0] = 0;
83
84			if (!ioctl (fd, TUNSETIFF, &ifr))
85			{
86			strncpy (ifrname, ifr.ifr_name, IFNAMSIZ);
87			ifrname [IFNAMSIZ] = 0;
88			}
89			else
90			{
91			slog (L_CRIT, _("unable to configure tun/tap interface: %s"), strerror (errno));
92			exit (1);
93			}
94
95	pcg	1.2	if (ioctl (fd, TUNSETPERSIST, conf.ifpersist ? 1 : 0))
96			slog (L_WARN, _("cannot set persistency mode for device %s: %s"), ifrname, strerror (errno));
97	pcg	1.1
98			slog (L_DEBUG, _("%s is a %s"), device, info ());
99			}
100
101			tap_device::~tap_device ()
102			{
103			close (fd);
104			}
105
106			tap_packet *
107			tap_device::recv ()
108			{
109			tap_packet *pkt = new tap_packet;
110
111	pcg	1.4	#if TEST_ETHEREMU
112			pkt->len = read (fd, &((*pkt)[14]), MAX_MTU - 14);
113			#else
114	pcg	1.1	pkt->len = read (fd, &((*pkt)[0]), MAX_MTU);
115	pcg	1.4	#endif
116	pcg	1.1
117			if (pkt->len <= 0)
118			{
119	pcg	1.3	delete pkt;
120	pcg	1.1	slog (L_ERR, _("error while reading from %s %s: %s"),
121			info (), DEFAULT_DEVICE, strerror (errno));
122			return 0;
123			}
124
125	pcg	1.4	#if TEST_ETHEREMU
126			pkt->len += 14;
127
128			// assume ipv4
129			(*pkt)[12] = 0x08;
130			(*pkt)[13] = 0x00;
131
132			if (!ether_emu.tun_to_tap (pkt))
133			{
134			delete pkt;
135			return 0;
136			}
137			#endif
138
139	pcg	1.1	return pkt;
140			}
141
142			void
143			tap_device::send (tap_packet *pkt)
144			{
145	pcg	1.4	#if TEST_ETHEREMU
146			if (ether_emu.tap_to_tun (pkt) &&
147			write (fd, &((*pkt)[14]), pkt->len - 14) < 0)
148			#else
149	pcg	1.1	if (write (fd, &((*pkt)[0]), pkt->len) < 0)
150	pcg	1.4	#endif
151	pcg	1.1	slog (L_ERR, _("can't write to %s %s: %s"), info (), DEFAULT_DEVICE,
152			strerror (errno));
153			}
154