chiark / gitweb /
doc: Fix distribution of generated manpages.
[tripe] / server / tun-linux.c
CommitLineData
37075862 1/* -*-c-*-
2 *
3cdc3f3a 3 * $Id$
37075862 4 *
5 * Tunnel interface based on Linux TUN/TAP driver
6 *
7 * (c) 2003 Straylight/Edgeware
8 */
9
10/*----- Licensing notice --------------------------------------------------*
11 *
12 * This file is part of Trivial IP Encryption (TrIPE).
13 *
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.
18 *
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.
23 *
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.
27 */
28
37075862 29/*----- Header files ------------------------------------------------------*/
30
42da2a58 31#define TUN_INTERNALS
32
37075862 33#include "tripe.h"
34
42da2a58 35#ifdef TUN_LINUX
36# include <sys/ioctl.h>
37# include <linux/if.h>
38# include <linux/if_tun.h>
39#endif
37075862 40
41/*----- Main code ---------------------------------------------------------*/
42
42da2a58 43#ifdef TUN_LINUX
44
45struct tunnel {
46 const tunnel_ops *ops; /* Pointer to operations */
47 sel_file f; /* Selector for TUN/TAP device */
48 struct peer *p; /* Pointer to my peer */
42da2a58 49};
37075862 50
51/* --- @t_read@ --- *
52 *
53 * Arguments: @int fd@ = file descriptor to read
54 * @unsigned mode@ = what's happened
55 * @void *v@ = pointer to tunnel block
56 *
57 * Returns: ---
58 *
59 * Use: Reads data from the tunnel.
60 */
61
62static void t_read(int fd, unsigned mode, void *v)
63{
64 tunnel *t = v;
65 ssize_t n;
66 buf b;
67
68 n = read(fd, buf_i, sizeof(buf_i));
69 if (n < 0) {
72917fe7 70 a_warn("TUN", "%s", p_ifname(t->p), "read-error", "?ERRNO", A_END);
37075862 71 return;
72 }
73 IF_TRACING(T_TUNNEL, {
060ca767 74 trace(T_TUNNEL, "tun-linux: packet arrived");
75 trace_block(T_PACKET, "tun-linux: packet contents", buf_i, n);
37075862 76 })
77 buf_init(&b, buf_i, n);
78 p_tun(t->p, &b);
79}
80
42da2a58 81/* --- @t_init@ --- *
37075862 82 *
83 * Arguments: ---
84 *
85 * Returns: ---
86 *
87 * Use: Initializes the tunneling system. Maybe this will require
88 * opening file descriptors or something.
89 */
90
42da2a58 91static void t_init(void) { return; }
37075862 92
42da2a58 93/* --- @t_create@ --- *
37075862 94 *
42da2a58 95 * Arguments: @peer *p@ = pointer to peer block
72917fe7 96 * @char **ifn@ = where to put the interface name
37075862 97 *
42da2a58 98 * Returns: A tunnel block if it worked, or null on failure.
37075862 99 *
100 * Use: Initializes a new tunnel.
101 */
102
72917fe7 103static tunnel *t_create(peer *p, char **ifn)
37075862 104{
105 int fd;
106 int f;
107 struct ifreq iff;
42da2a58 108 tunnel *t;
37075862 109
110 if ((fd = open("/dev/net/tun", O_RDWR)) < 0) {
f43df819
MW
111 a_warn("TUN", "-", "linux",
112 "open-error", "/dev/net/tun", "?ERRNO",
113 A_END);
42da2a58 114 return (0);
37075862 115 }
116 fdflags(fd, O_NONBLOCK, O_NONBLOCK, FD_CLOEXEC, FD_CLOEXEC);
060ca767 117 memset(&iff, 0, sizeof(iff));
37075862 118 iff.ifr_name[0] = 0;
b9066fbb 119 iff.ifr_flags = IFF_TUN | IFF_NO_PI;
37075862 120 if ((f = ioctl(fd, TUNSETIFF, &iff)) < 0) {
f43df819 121 a_warn("TUN", "-", "linux", "config-error", "?ERRNO", A_END);
37075862 122 close(fd);
42da2a58 123 return (0);
37075862 124 }
42da2a58 125 t = CREATE(tunnel);
126 t->ops = &tun_linux;
37075862 127 t->p = p;
128 sel_initfile(&sel, &t->f, fd, SEL_READ, t_read, t);
129 sel_addfile(&t->f);
130 iff.ifr_name[IFNAMSIZ - 1] = 0;
72917fe7 131 *ifn = xstrdup(iff.ifr_name);
060ca767 132 T( trace(T_TUNNEL, "tun-linux: attached interface %s to peer `%s'",
72917fe7 133 *ifn, p_name(p)); )
42da2a58 134 return (t);
37075862 135}
136
42da2a58 137/* --- @t_inject@ --- *
37075862 138 *
139 * Arguments: @tunnel *t@ = pointer to tunnel block
140 * @buf *b@ = buffer to send
141 *
142 * Returns: ---
143 *
144 * Use: Injects a packet into the local network stack.
145 */
146
42da2a58 147static void t_inject(tunnel *t, buf *b)
37075862 148{
149 IF_TRACING(T_TUNNEL, {
060ca767 150 trace(T_TUNNEL, "tun-linux: inject decrypted packet");
37075862 151 trace_block(T_PACKET, "tunnel: packet contents", BBASE(b), BLEN(b));
152 })
153 write(t->f.fd, BBASE(b), BLEN(b));
154}
155
42da2a58 156/* --- @t_destroy@ --- *
37075862 157 *
158 * Arguments: @tunnel *t@ = pointer to tunnel block
159 *
160 * Returns: ---
161 *
162 * Use: Destroys a tunnel.
163 */
164
42da2a58 165static void t_destroy(tunnel *t)
37075862 166{
167 sel_rmfile(&t->f);
168 close(t->f.fd);
42da2a58 169 DESTROY(t);
37075862 170}
171
42da2a58 172const tunnel_ops tun_linux = {
173 "linux",
174 t_init,
175 t_create,
72917fe7 176 0,
42da2a58 177 t_inject,
178 t_destroy
179};
180
181#endif
182
37075862 183/*----- That's all, folks -------------------------------------------------*/