3 * Tunnel interface for 4.4BSD-derived systems
5 * (c) 2001 Straylight/Edgeware
8 /*----- Licensing notice --------------------------------------------------*
10 * This file is part of Trivial IP Encryption (TrIPE).
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.
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.
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.
27 /*----- Header files ------------------------------------------------------*/
33 /*----- Main code ---------------------------------------------------------*/
38 const tunnel_ops *ops; /* Pointer to operations */
39 sel_file f; /* Selector for tunnel device */
40 struct peer *p; /* Pointer to my peer */
45 * Arguments: @int fd@ = file descriptor to read
46 * @unsigned mode@ = what's happened
47 * @void *v@ = pointer to tunnel block
51 * Use: Reads data from the tunnel.
54 static void t_read(int fd, unsigned mode, void *v)
60 n = read(fd, buf_i, sizeof(buf_i));
62 a_warn("TUN", "%s", p_ifname(t->p), "read-error", "?ERRNO", A_END);
65 IF_TRACING(T_TUNNEL, {
66 trace(T_TUNNEL, "tun-bsd: packet arrived");
67 trace_block(T_PACKET, "tun-bsd: packet contents", buf_i, n);
69 buf_init(&b, buf_i, n);
79 * Use: Initializes the tunneling system. Maybe this will require
80 * opening file descriptors or something.
83 static void t_init(void) { return; }
87 * Arguments: @char **ifn@ = where to put the interface name
89 * Returns: A file descriptor, or @-1@ on failure.
91 * Use: Opens a tunnel device. This will run with root privileges
92 * even if the rest of the server has dropped them.
95 static int t_open(char **ifn)
103 sprintf(buf, "/dev/tun%u", n);
104 if ((fd = open(buf, O_RDWR)) >= 0)
108 T( trace(T_TUNNEL, "tunnel device %u busy: skipping", n); )
111 a_warn("TUN", "-", "bsd", "no-tunnel-devices", A_END);
114 a_warn("TUN", "-", "open-error", "%s", buf, "?ERRNO", A_END);
122 /* --- @t_create@ --- *
124 * Arguments: @peer *p@ = pointer to peer block
125 * @int fd@ = file descriptor of tunnel device
126 * @char **ifn@ = where to put the interface name
128 * Returns: A tunnel block if it worked, or null on failure.
130 * Use: Initializes a new tunnel.
133 static tunnel *t_create(peer *p, int fd, char **ifn)
137 fdflags(fd, O_NONBLOCK, O_NONBLOCK, FD_CLOEXEC, FD_CLOEXEC);
141 sel_initfile(&sel, &t->f, fd, SEL_READ, t_read, t);
146 /* --- @t_inject@ --- *
148 * Arguments: @tunnel *t@ = pointer to tunnel block
149 * @buf *b@ = buffer to send
153 * Use: Injects a packet into the local network stack.
156 static void t_inject(tunnel *t, buf *b)
158 IF_TRACING(T_TUNNEL, {
159 trace(T_TUNNEL, "tun-bsd: inject decrypted packet");
160 trace_block(T_PACKET, "tun-bsd: packet contents", BBASE(b), BLEN(b));
162 write(t->f.fd, BBASE(b), BLEN(b));
165 /* --- @t_destroy@ --- *
167 * Arguments: @tunnel *t@ = pointer to tunnel block
171 * Use: Destroys a tunnel.
174 static void t_destroy(tunnel *t)
175 { sel_rmfile(&t->f); close(t->f.fd); DESTROY(t); }
177 const tunnel_ops tun_bsd = {
189 /*----- That's all, folks -------------------------------------------------*/