1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
|
/*
Copyright (c) 2012-2013, Matthias Schiffer <mschiffer@universe-factory.net>
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "fastd.h"
#include <fcntl.h>
#include <net/if.h>
#include <sys/ioctl.h>
#if defined(__linux__)
#include <linux/if_tun.h>
void fastd_tuntap_open(fastd_context_t *ctx) {
struct ifreq ifr = {};
pr_debug(ctx, "initializing tun/tap device...");
if ((ctx->tunfd = open("/dev/net/tun", O_RDWR|O_CLOEXEC|O_NONBLOCK)) < 0)
exit_errno(ctx, "could not open tun/tap device file");
if (ctx->conf->ifname)
strncpy(ifr.ifr_name, ctx->conf->ifname, IFNAMSIZ-1);
switch (ctx->conf->mode) {
case MODE_TAP:
ifr.ifr_flags = IFF_TAP;
break;
case MODE_TUN:
ifr.ifr_flags = IFF_TUN;
break;
default:
exit_bug(ctx, "invalid mode");
}
ifr.ifr_flags |= IFF_NO_PI;
if (ioctl(ctx->tunfd, TUNSETIFF, &ifr) < 0)
exit_errno(ctx, "TUNSETIFF ioctl failed");
ctx->ifname = strndup(ifr.ifr_name, IFNAMSIZ-1);
int ctl_sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
if (ctl_sock < 0)
exit_errno(ctx, "socket");
if (ioctl(ctl_sock, SIOCGIFMTU, &ifr) < 0)
exit_errno(ctx, "SIOCGIFMTU ioctl failed");
if (ifr.ifr_mtu != ctx->conf->mtu) {
ifr.ifr_mtu = ctx->conf->mtu;
if (ioctl(ctl_sock, SIOCSIFMTU, &ifr) < 0)
exit_errno(ctx, "SIOCSIFMTU ioctl failed");
}
if (close(ctl_sock))
pr_error_errno(ctx, "close");
pr_debug(ctx, "tun/tap device initialized.");
}
#elif defined(__FreeBSD__)
#include <net/if_tun.h>
#include <net/if_tap.h>
static void get_tap_name(fastd_context_t *ctx) {
struct ifreq ifr = {};
if (ioctl(ctx->tunfd, TAPGIFNAME, &ifr) < 0)
exit_errno(ctx, "TAPGIFNAME ioctl failed");
free(ctx->ifname);
ctx->ifname = strndup(ifr.ifr_name, IFNAMSIZ-1);
}
static void set_tap_mtu(fastd_context_t *ctx) {
struct tapinfo tapinfo;
if (ioctl(ctx->tunfd, TAPGIFINFO, &tapinfo) < 0)
exit_errno(ctx, "TAPGIFINFO ioctl failed");
tapinfo.mtu = ctx->conf->mtu;
if (ioctl(ctx->tunfd, TAPSIFINFO, &tapinfo) < 0)
exit_errno(ctx, "TAPSIFINFO ioctl failed");
}
static void set_tun_mtu(fastd_context_t *ctx) {
struct tuninfo tuninfo;
if (ioctl(ctx->tunfd, TUNGIFINFO, &tuninfo) < 0)
exit_errno(ctx, "TUNGIFINFO ioctl failed");
tuninfo.mtu = ctx->conf->mtu;
if (ioctl(ctx->tunfd, TUNSIFINFO, &tuninfo) < 0)
exit_errno(ctx, "TUNSIFINFO ioctl failed");
}
void fastd_tuntap_open(fastd_context_t *ctx) {
pr_debug(ctx, "initializing tun/tap device...");
char ifname[5+IFNAMSIZ] = "/dev/";
if (ctx->conf->ifname) {
strncat(ifname, ctx->conf->ifname, IFNAMSIZ-1);
}
else {
switch (ctx->conf->mode) {
case MODE_TAP:
strncat(ifname, "tap", IFNAMSIZ-1);
break;
case MODE_TUN:
strncat(ifname, "tun", IFNAMSIZ-1);
break;
default:
exit_bug(ctx, "invalid mode");
}
}
if ((ctx->tunfd = open(ifname, O_RDWR|O_CLOEXEC|O_NONBLOCK)) < 0)
exit_errno(ctx, "could not open tun/tap device file");
if (!(ctx->ifname = fdevname_r(ctx->tunfd, malloc(IFNAMSIZ), IFNAMSIZ)))
exit_errno(ctx, "could not get tun/tap interface name");
switch (ctx->conf->mode) {
case MODE_TAP:
if (strncmp(ctx->ifname, "tap", 3) != 0)
exit_error(ctx, "opened device doesn't to be a tap device");
get_tap_name(ctx);
set_tap_mtu(ctx);
break;
case MODE_TUN:
if (strncmp(ctx->ifname, "tun", 3) != 0)
exit_error(ctx, "opened device doesn't to be a tun device");
set_tun_mtu(ctx);
break;
default:
exit_bug(ctx, "invalid mode");
}
pr_debug(ctx, "tun/tap device initialized.");
}
#else
#error unknown tun/tap implementation
#endif
void fastd_tuntap_close(fastd_context_t *ctx) {
if (close(ctx->tunfd))
pr_warn_errno(ctx, "closing tun/tap: close");
free(ctx->ifname);
}
|
