chiark / gitweb /
server/tun-slip.c: Fix signed/unsigned char mismatch.
[tripe] / server / tun-linux.c
CommitLineData
37075862 1/* -*-c-*-
2 *
37075862 3 * Tunnel interface based on Linux TUN/TAP driver
4 *
5 * (c) 2003 Straylight/Edgeware
6 */
7
e04c2d50 8/*----- Licensing notice --------------------------------------------------*
37075862 9 *
10 * This file is part of Trivial IP Encryption (TrIPE).
11 *
12 * TrIPE is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
e04c2d50 16 *
37075862 17 * TrIPE is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
e04c2d50 21 *
37075862 22 * You should have received a copy of the GNU General Public License
23 * along with TrIPE; if not, write to the Free Software Foundation,
24 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
25 */
26
37075862 27/*----- Header files ------------------------------------------------------*/
28
42da2a58 29#define TUN_INTERNALS
30
37075862 31#include "tripe.h"
32
42da2a58 33#ifdef TUN_LINUX
34# include <sys/ioctl.h>
35# include <linux/if.h>
36# include <linux/if_tun.h>
37#endif
37075862 38
39/*----- Main code ---------------------------------------------------------*/
40
42da2a58 41#ifdef TUN_LINUX
42
43struct tunnel {
44 const tunnel_ops *ops; /* Pointer to operations */
45 sel_file f; /* Selector for TUN/TAP device */
46 struct peer *p; /* Pointer to my peer */
e04c2d50 47};
37075862 48
49/* --- @t_read@ --- *
50 *
51 * Arguments: @int fd@ = file descriptor to read
52 * @unsigned mode@ = what's happened
53 * @void *v@ = pointer to tunnel block
54 *
55 * Returns: ---
56 *
57 * Use: Reads data from the tunnel.
58 */
59
60static void t_read(int fd, unsigned mode, void *v)
61{
62 tunnel *t = v;
63 ssize_t n;
64 buf b;
65
66 n = read(fd, buf_i, sizeof(buf_i));
67 if (n < 0) {
b476642f
MW
68 a_warn("TUN", "%s", p_ifname(t->p), "linux",
69 "read-error", "?ERRNO", A_END);
37075862 70 return;
71 }
72 IF_TRACING(T_TUNNEL, {
060ca767 73 trace(T_TUNNEL, "tun-linux: packet arrived");
74 trace_block(T_PACKET, "tun-linux: packet contents", buf_i, n);
37075862 75 })
76 buf_init(&b, buf_i, n);
77 p_tun(t->p, &b);
78}
79
42da2a58 80/* --- @t_init@ --- *
37075862 81 *
82 * Arguments: ---
83 *
84 * Returns: ---
85 *
86 * Use: Initializes the tunneling system. Maybe this will require
87 * opening file descriptors or something.
88 */
89
42da2a58 90static void t_init(void) { return; }
37075862 91
eb5f3fea
MW
92/* --- @t_create@ --- *
93 *
94 * Arguments: @peer *p@ = pointer to peer block
95 * @int fd@ = file descriptor of tunnel device
96 * @char **ifn@ = where to put the interface name
97 *
98 * Returns: A tunnel block if it worked, or null on failure.
99 *
100 * Use: Initializes a new tunnel.
101 */
102
103static tunnel *t_create(peer *p, int fd, char **ifn)
104{
105 tunnel *t;
106
107 fdflags(fd, O_NONBLOCK, O_NONBLOCK, FD_CLOEXEC, FD_CLOEXEC);
42da2a58 108 t = CREATE(tunnel);
109 t->ops = &tun_linux;
37075862 110 t->p = p;
111 sel_initfile(&sel, &t->f, fd, SEL_READ, t_read, t);
112 sel_addfile(&t->f);
42da2a58 113 return (t);
37075862 114}
115
42da2a58 116/* --- @t_inject@ --- *
37075862 117 *
118 * Arguments: @tunnel *t@ = pointer to tunnel block
119 * @buf *b@ = buffer to send
120 *
121 * Returns: ---
122 *
123 * Use: Injects a packet into the local network stack.
124 */
125
42da2a58 126static void t_inject(tunnel *t, buf *b)
37075862 127{
128 IF_TRACING(T_TUNNEL, {
060ca767 129 trace(T_TUNNEL, "tun-linux: inject decrypted packet");
37075862 130 trace_block(T_PACKET, "tunnel: packet contents", BBASE(b), BLEN(b));
131 })
23df0e5b 132 IGNORE(write(t->f.fd, BBASE(b), BLEN(b)));
37075862 133}
134
42da2a58 135/* --- @t_destroy@ --- *
37075862 136 *
137 * Arguments: @tunnel *t@ = pointer to tunnel block
138 *
139 * Returns: ---
140 *
141 * Use: Destroys a tunnel.
142 */
143
42da2a58 144static void t_destroy(tunnel *t)
6047fbac 145 { sel_rmfile(&t->f); close(t->f.fd); DESTROY(t); }
37075862 146
42da2a58 147const tunnel_ops tun_linux = {
148 "linux",
388e0319 149 TUNF_PRIVOPEN,
42da2a58 150 t_init,
151 t_create,
72917fe7 152 0,
42da2a58 153 t_inject,
154 t_destroy
155};
156
157#endif
158
37075862 159/*----- That's all, folks -------------------------------------------------*/