5 * Tunnel interface for 4.4BSD-derived systems
7 * (c) 2001 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 /*----- Main code ---------------------------------------------------------*/
35 #if TUN_TYPE != TUN_BSD
36 # error "Tunnel type mismatch: fix the Makefile"
41 * Arguments: @int fd@ = file descriptor to read
42 * @unsigned mode@ = what's happened
43 * @void *v@ = pointer to tunnel block
47 * Use: Reads data from the tunnel.
50 void t_read(int fd
, unsigned mode
, void *v
)
56 n
= read(fd
, buf_i
, sizeof(buf_i
));
58 a_warn("TUN %s read-error -- %s", tun_ifname(t
), strerror(errno
));
61 IF_TRACING(T_TUNNEL
, {
62 trace(T_TUNNEL
, "tunnel: packet arrived");
63 trace_block(T_PACKET
, "tunnel: packet contents", buf_i
, n
);
65 buf_init(&b
, buf_i
, n
);
69 /* --- @tun_init@ --- *
75 * Use: Initializes the tunneling system. Maybe this will require
76 * opening file descriptors or something.
84 /* --- @tun_create@ --- *
86 * Arguments: @tunnel *t@ = pointer to tunnel block
87 * @peer *p@ = pointer to peer block
89 * Returns: Zero if it worked, nonzero on failure.
91 * Use: Initializes a new tunnel.
94 int tun_create(tunnel
*t
, peer
*p
)
102 sprintf(buf
, "/dev/tun%u", n
);
103 if ((fd
= open(buf
, O_RDWR
)) >= 0)
107 T( trace(T_TUNNEL
, "tunnel device %u busy: skipping", n
); )
110 a_warn("TUN - bsd no-tunnel-devices");
113 a_warn("TUN - open-error %s -- %s", buf
, strerror(errno
));
119 fdflags(fd
, O_NONBLOCK
, O_NONBLOCK
, FD_CLOEXEC
, FD_CLOEXEC
);
122 sel_initfile(&sel
, &t
->f
, fd
, SEL_READ
, t_read
, t
);
124 T( trace(T_TUNNEL
, "tunnel: attached interface %s to peer `%s'",
125 tun_ifname(t
), p_name(p
)); )
129 /* --- @tun_ifname@ --- *
131 * Arguments: @tunnel *t@ = pointer to tunnel block
133 * Returns: A pointer to the tunnel's interface name.
136 const char *tun_ifname(tunnel
*t
)
139 sprintf(buf
, "tun%u", t
->n
);
143 /* --- @tun_inject@ --- *
145 * Arguments: @tunnel *t@ = pointer to tunnel block
146 * @buf *b@ = buffer to send
150 * Use: Injects a packet into the local network stack.
153 void tun_inject(tunnel
*t
, buf
*b
)
155 IF_TRACING(T_TUNNEL
, {
156 trace(T_TUNNEL
, "tunnel: inject decrypted packet");
157 trace_block(T_PACKET
, "tunnel: packet contents", BBASE(b
), BLEN(b
));
159 write(t
->f
.fd
, BBASE(b
), BLEN(b
));
162 /* --- @tun_destroy@ --- *
164 * Arguments: @tunnel *t@ = pointer to tunnel block
168 * Use: Destroys a tunnel.
171 void tun_destroy(tunnel
*t
)
177 /*----- That's all, folks -------------------------------------------------*/