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Don't link the client against Catacomb.
[tripe] / tun-bsd.c
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fd528bde 1/* -*-c-*-
2 *
3 * $Id: tun-bsd.c,v 1.1 2001/02/05 19:48:18 mdw Exp $
4 *
5 * Tunnel interface for 4.4BSD-derived systems
6 *
7 * (c) 2001 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
29/*----- Revision history --------------------------------------------------*
30 *
31 * $Log: tun-bsd.c,v $
32 * Revision 1.1 2001/02/05 19:48:18 mdw
33 * Initial support for BSD tunnel devices.
34 *
35 */
36
37/*----- Header files ------------------------------------------------------*/
38
39#include "tripe.h"
40
41/*----- Main code ---------------------------------------------------------*/
42
43#if TUN_TYPE != TUN_BSD
44# error "Tunnel type mismatch: fix the Makefile"
45#endif
46
47/* --- @t_read@ --- *
48 *
49 * Arguments: @int fd@ = file descriptor to read
50 * @unsigned mode@ = what's happened
51 * @void *v@ = pointer to tunnel block
52 *
53 * Returns: ---
54 *
55 * Use: Reads data from the tunnel.
56 */
57
58void t_read(int fd, unsigned mode, void *v)
59{
60 tunnel *t = v;
61 ssize_t n;
62 buf b;
63
64 n = read(fd, buf_i, sizeof(buf_i));
65 if (n < 0) {
66 a_warn("tunnel read failed (%s): %s", tun_ifname(t), strerror(errno));
67 return;
68 }
69 IF_TRACING(T_TUNNEL, {
70 trace(T_TUNNEL, "tunnel: packet arrived");
71 trace_block(T_PACKET, "tunnel: packet contents", buf_i, n);
72 })
73 buf_init(&b, buf_i, n);
74 p_tun(t->p, &b);
75}
76
77/* --- @tun_init@ --- *
78 *
79 * Arguments: ---
80 *
81 * Returns: ---
82 *
83 * Use: Initializes the tunneling system. Maybe this will require
84 * opening file descriptors or something.
85 */
86
87void tun_init(void)
88{
89 return;
90}
91
92/* --- @tun_create@ --- *
93 *
94 * Arguments: @tunnel *t@ = pointer to tunnel block
95 * @peer *p@ = pointer to peer block
96 *
97 * Returns: Zero if it worked, nonzero on failure.
98 *
99 * Use: Initializes a new tunnel.
100 */
101
102int tun_create(tunnel *t, peer *p)
103{
104 int fd;
105 unsigned n;
106 char buf[16];
107
108 n = 0;
109 for (;;) {
110 sprintf(buf, "/dev/tun%u", n);
111 if ((fd = open("/dev/unet", O_RDWR)) >= 0)
112 break;
113 switch (errno) {
114 case EBUSY:
115 T( trace(T_TUNNEL, "tunnel device %u busy: skipping", n); )
116 break;
117 case ENOENT:
118 a_warn("no suitable tunnel devices found");
119 return (-1);
120 default:
121 a_warn("error opening `%s': %s (skipping)", buf, strerror(errno));
122 break;
123 }
124 n++;
125 }
126
127 fdflags(fd, O_NONBLOCK, O_NONBLOCK, FD_CLOEXEC, FD_CLOEXEC);
128 t->p = p;
129 t->n = n;
130 sel_initfile(&sel, &t->f, fd, SEL_READ, t_read, t);
131 sel_addfile(&t->f);
132 T( trace(T_TUNNEL, "tunnel: attached interface %s to peer `%s'",
133 tun_ifname(t), p_name(p)); )
134 return (0);
135}
136
137/* --- @tun_ifname@ --- *
138 *
139 * Arguments: @tunnel *t@ = pointer to tunnel block
140 *
141 * Returns: A pointer to the tunnel's interface name.
142 */
143
144const char *tun_ifname(tunnel *t)
145{
146 static char buf[8];
147 sprintf(buf, "tun%u", t->n);
148 return (buf);
149}
150
151/* --- @tun_inject@ --- *
152 *
153 * Arguments: @tunnel *t@ = pointer to tunnel block
154 * @buf *b@ = buffer to send
155 *
156 * Returns: ---
157 *
158 * Use: Injects a packet into the local network stack.
159 */
160
161void tun_inject(tunnel *t, buf *b)
162{
163 IF_TRACING(T_TUNNEL, {
164 trace(T_TUNNEL, "tunnel: inject decrypted packet");
165 trace_block(T_PACKET, "tunnel: packet contents", BBASE(b), BLEN(b));
166 })
167 write(t->f.fd, BBASE(b), BLEN(b));
168}
169
170/* --- @tun_destroy@ --- *
171 *
172 * Arguments: @tunnel *t@ = pointer to tunnel block
173 *
174 * Returns: ---
175 *
176 * Use: Destroys a tunnel.
177 */
178
179void tun_destroy(tunnel *t)
180{
181 sel_rmfile(&t->f);
182 close(t->f.fd);
183}
184
185/*----- That's all, folks -------------------------------------------------*/