chiark / gitweb /
server/keyset.c, server/keymgmt.c: Variable data limits.
[tripe] / server / tun-unet.c
CommitLineData
410c8acf 1/* -*-c-*-
2 *
410c8acf 3 * Tunnel interface based on Linux Usernet
4 *
5 * (c) 2001 Straylight/Edgeware
6 */
7
e04c2d50 8/*----- Licensing notice --------------------------------------------------*
410c8acf 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 *
410c8acf 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 *
410c8acf 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
410c8acf 27/*----- Header files ------------------------------------------------------*/
28
42da2a58 29#define TUN_INTERNALS
30
410c8acf 31#include "tripe.h"
32
42da2a58 33#ifdef TUN_UNET
34# include <sys/ioctl.h>
35# include <net/if.h>
36# include <unet.h>
37#endif
410c8acf 38
39/*----- Main code ---------------------------------------------------------*/
40
42da2a58 41#ifdef TUN_UNET
42
43struct tunnel {
44 const tunnel_ops *ops; /* Pointer to operations */
45 sel_file f; /* Selector for Usernet device */
46 struct peer *p; /* Pointer to my peer */
47};
48
410c8acf 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
60a837d8 60static void t_read(int fd, unsigned mode, void *v)
410c8acf 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) {
72917fe7 68 a_warn("TUN", "%s", p_ifname(t->p), "read-error", "?ERRNO", A_END);
410c8acf 69 return;
70 }
71 IF_TRACING(T_TUNNEL, {
060ca767 72 trace(T_TUNNEL, "tun-unet: packet arrived");
73 trace_block(T_PACKET, "tun-unet: packet contents", buf_i, n);
410c8acf 74 })
75 buf_init(&b, buf_i, n);
76 p_tun(t->p, &b);
77}
78
42da2a58 79/* --- @t_init@ --- *
410c8acf 80 *
81 * Arguments: ---
82 *
83 * Returns: ---
84 *
85 * Use: Initializes the tunneling system. Maybe this will require
86 * opening file descriptors or something.
87 */
88
42da2a58 89static void t_init(void) { return; }
410c8acf 90
42da2a58 91/* --- @t_create@ --- *
410c8acf 92 *
93 * Arguments: @tunnel *t@ = pointer to tunnel block
94 * @peer *p@ = pointer to peer block
72917fe7 95 * @char *ifn@ = where to put the interface name
410c8acf 96 *
42da2a58 97 * Returns: A tunnel block if it worked, or null on failure.
410c8acf 98 *
99 * Use: Initializes a new tunnel.
100 */
101
72917fe7 102static tunnel *t_create(peer *p, char **ifn)
410c8acf 103{
104 int fd;
42da2a58 105 tunnel *t;
a368bfbc 106 int f;
72917fe7 107 struct unet_info uni;
410c8acf 108
109 if ((fd = open("/dev/unet", O_RDWR)) < 0) {
f43df819 110 a_warn("TUN", "-", "unet", "open-error", "/dev/unet", "?ERRNO", A_END);
42da2a58 111 return (0);
410c8acf 112 }
650a6624 113 fdflags(fd, O_NONBLOCK, O_NONBLOCK, FD_CLOEXEC, FD_CLOEXEC);
a368bfbc 114 if ((f = ioctl(fd, UNIOCGIFFLAGS)) < 0 ||
115 ioctl(fd, UNIOCSIFFLAGS, f | IFF_POINTOPOINT)) {
f43df819 116 a_warn("TUN", "-", "unet", "config-error", "?ERRNO", A_END);
a368bfbc 117 close(fd);
42da2a58 118 return (0);
a368bfbc 119 }
42da2a58 120 t = CREATE(tunnel);
121 t->ops = &tun_unet;
410c8acf 122 t->p = p;
123 sel_initfile(&sel, &t->f, fd, SEL_READ, t_read, t);
124 sel_addfile(&t->f);
72917fe7
MW
125
126 if (ioctl(t->f.fd, UNIOCGINFO, &uni)) {
127 a_warn("TUN", "-", "unet", "getinfo-error", "?ERRNO", A_END);
dfc1ab4f 128 return (0);
72917fe7
MW
129 }
130 *ifn = xstrdup(uni.uni_ifname);
060ca767 131 T( trace(T_TUNNEL, "tun-unet: attached interface %s to peer `%s'",
72917fe7 132 *ifn, p_name(p)); )
42da2a58 133 return (t);
410c8acf 134}
135
42da2a58 136/* --- @t_inject@ --- *
410c8acf 137 *
138 * Arguments: @tunnel *t@ = pointer to tunnel block
139 * @buf *b@ = buffer to send
140 *
141 * Returns: ---
142 *
143 * Use: Injects a packet into the local network stack.
144 */
145
42da2a58 146static void t_inject(tunnel *t, buf *b)
410c8acf 147{
148 IF_TRACING(T_TUNNEL, {
060ca767 149 trace(T_TUNNEL, "tun-unet: inject decrypted packet");
150 trace_block(T_PACKET, "tun-unet: packet contents", BBASE(b), BLEN(b));
410c8acf 151 })
152 write(t->f.fd, BBASE(b), BLEN(b));
153}
154
42da2a58 155/* --- @t_destroy@ --- *
410c8acf 156 *
157 * Arguments: @tunnel *t@ = pointer to tunnel block
158 *
159 * Returns: ---
160 *
161 * Use: Destroys a tunnel.
162 */
163
42da2a58 164static void t_destroy(tunnel *t)
6047fbac 165 { sel_rmfile(&t->f); close(t->f.fd); DESTROY(t); }
410c8acf 166
42da2a58 167const tunnel_ops tun_unet = {
168 "unet",
169 t_init,
170 t_create,
72917fe7 171 0,
42da2a58 172 t_inject,
173 t_destroy
174};
175
176#endif
177
410c8acf 178/*----- That's all, folks -------------------------------------------------*/