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/cvs/gvpe/src/device-linux.C
Revision: 1.3
Committed: Tue Oct 14 03:22:09 2003 UTC (20 years, 7 months ago) by pcg
Content type: text/plain
Branch: MAIN
Changes since 1.2: +10 -2 lines
Log Message:
*** empty log message ***

File Contents

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