5 * Tunnel interface based on Linux TUN/TAP driver
7 * (c) 2003 Straylight/Edgeware
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of Trivial IP Encryption (TrIPE).
14 * TrIPE is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
19 * TrIPE is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with TrIPE; if not, write to the Free Software Foundation,
26 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
29 /*----- Header files ------------------------------------------------------*/
33 #include <sys/ioctl.h>
35 /*----- Main code ---------------------------------------------------------*/
37 #if TUN_TYPE != TUN_LINUX
38 # error "Tunnel type mismatch: fix the Makefile"
43 * Arguments: @int fd@ = file descriptor to read
44 * @unsigned mode@ = what's happened
45 * @void *v@ = pointer to tunnel block
49 * Use: Reads data from the tunnel.
52 static void t_read(int fd
, unsigned mode
, void *v
)
58 n
= read(fd
, buf_i
, sizeof(buf_i
));
60 a_warn("TUN %s read-error -- %s", t
->ifn
, strerror(errno
));
63 IF_TRACING(T_TUNNEL
, {
64 trace(T_TUNNEL
, "tunnel: packet arrived");
65 trace_block(T_PACKET
, "tunnel: packet contents", buf_i
, n
);
67 buf_init(&b
, buf_i
, n
);
71 /* --- @tun_init@ --- *
77 * Use: Initializes the tunneling system. Maybe this will require
78 * opening file descriptors or something.
86 /* --- @tun_create@ --- *
88 * Arguments: @tunnel *t@ = pointer to tunnel block
89 * @peer *p@ = pointer to peer block
91 * Returns: Zero if it worked, nonzero on failure.
93 * Use: Initializes a new tunnel.
96 int tun_create(tunnel
*t
, peer
*p
)
102 if ((fd
= open("/dev/net/tun", O_RDWR
)) < 0) {
103 a_warn("TUN - open-error /dev/net/tun -- %s", strerror(errno
));
106 fdflags(fd
, O_NONBLOCK
, O_NONBLOCK
, FD_CLOEXEC
, FD_CLOEXEC
);
108 iff
.ifr_flags
= IFF_TUN
;
109 if ((f
= ioctl(fd
, TUNSETIFF
, &iff
)) < 0) {
110 a_warn("TUN - linux config-error -- %s", strerror(errno
));
115 sel_initfile(&sel
, &t
->f
, fd
, SEL_READ
, t_read
, t
);
117 iff
.ifr_name
[IFNAMSIZ
- 1] = 0;
118 strcpy(t
->ifn
, iff
.ifr_name
);
119 T( trace(T_TUNNEL
, "tunnel: attached interface %s to peer `%s'",
120 t
->ifn
, p_name(p
)); )
124 /* --- @tun_ifname@ --- *
126 * Arguments: @tunnel *t@ = pointer to tunnel block
128 * Returns: A pointer to the tunnel's interface name.
131 const char *tun_ifname(tunnel
*t
)
136 /* --- @tun_inject@ --- *
138 * Arguments: @tunnel *t@ = pointer to tunnel block
139 * @buf *b@ = buffer to send
143 * Use: Injects a packet into the local network stack.
146 void tun_inject(tunnel
*t
, buf
*b
)
148 IF_TRACING(T_TUNNEL
, {
149 trace(T_TUNNEL
, "tunnel: inject decrypted packet");
150 trace_block(T_PACKET
, "tunnel: packet contents", BBASE(b
), BLEN(b
));
152 write(t
->f
.fd
, BBASE(b
), BLEN(b
));
155 /* --- @tun_destroy@ --- *
157 * Arguments: @tunnel *t@ = pointer to tunnel block
161 * Use: Destroys a tunnel.
164 void tun_destroy(tunnel
*t
)
170 /*----- That's all, folks -------------------------------------------------*/