3 * $Id: tun-unet.c,v 1.4 2001/02/19 19:10:45 mdw Exp $
5 * Tunnel interface based on Linux Usernet
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 /*----- Revision history --------------------------------------------------*
31 * $Log: tun-unet.c,v $
32 * Revision 1.4 2001/02/19 19:10:45 mdw
33 * Set unet devices to be point-to-point.
35 * Revision 1.3 2001/02/05 19:55:00 mdw
36 * Guard against inappropriate compilation.
38 * Revision 1.2 2001/02/04 17:10:58 mdw
39 * Make file descriptors be nonblocking and close-on-exec.
41 * Revision 1.1 2001/02/03 20:26:37 mdw
46 /*----- Header files ------------------------------------------------------*/
50 #include <sys/ioctl.h>
54 /*----- Main code ---------------------------------------------------------*/
56 #if TUN_TYPE != TUN_UNET
57 # error "Tunnel type mismatch: fix the Makefile"
62 * Arguments: @int fd@ = file descriptor to read
63 * @unsigned mode@ = what's happened
64 * @void *v@ = pointer to tunnel block
68 * Use: Reads data from the tunnel.
71 void t_read(int fd, unsigned mode, void *v)
77 n = read(fd, buf_i, sizeof(buf_i));
79 a_warn("tunnel read failed (%s): %s", tun_ifname(t), strerror(errno));
82 IF_TRACING(T_TUNNEL, {
83 trace(T_TUNNEL, "tunnel: packet arrived");
84 trace_block(T_PACKET, "tunnel: packet contents", buf_i, n);
86 buf_init(&b, buf_i, n);
90 /* --- @tun_init@ --- *
96 * Use: Initializes the tunneling system. Maybe this will require
97 * opening file descriptors or something.
105 /* --- @tun_create@ --- *
107 * Arguments: @tunnel *t@ = pointer to tunnel block
108 * @peer *p@ = pointer to peer block
110 * Returns: Zero if it worked, nonzero on failure.
112 * Use: Initializes a new tunnel.
115 int tun_create(tunnel *t, peer *p)
120 if ((fd = open("/dev/unet", O_RDWR)) < 0) {
121 a_warn("open `/dev/unet' failed: %s", strerror(errno));
124 fdflags(fd, O_NONBLOCK, O_NONBLOCK, FD_CLOEXEC, FD_CLOEXEC);
125 if ((f = ioctl(fd, UNIOCGIFFLAGS)) < 0 ||
126 ioctl(fd, UNIOCSIFFLAGS, f | IFF_POINTOPOINT)) {
127 a_warn("couldn't set point-to-point flag: %s", strerror(errno));
132 sel_initfile(&sel, &t->f, fd, SEL_READ, t_read, t);
134 T( trace(T_TUNNEL, "tunnel: attached interface %s to peer `%s'",
135 tun_ifname(t), p_name(p)); )
139 /* --- @tun_ifname@ --- *
141 * Arguments: @tunnel *t@ = pointer to tunnel block
143 * Returns: A pointer to the tunnel's interface name.
146 const char *tun_ifname(tunnel *t)
148 static char b[UNET_NAMEMAX];
149 struct unet_info uni;
150 if (ioctl(t->f.fd, UNIOCGINFO, &uni)) {
151 a_warn("ioctl(UNIOCGINFO) failed: %s", strerror(errno));
154 if (strlen(uni.uni_ifname) + 1 > sizeof(b)) {
155 a_warn("interface name too long!");
158 strcpy(b, uni.uni_ifname);
162 /* --- @tun_inject@ --- *
164 * Arguments: @tunnel *t@ = pointer to tunnel block
165 * @buf *b@ = buffer to send
169 * Use: Injects a packet into the local network stack.
172 void tun_inject(tunnel *t, buf *b)
174 IF_TRACING(T_TUNNEL, {
175 trace(T_TUNNEL, "tunnel: inject decrypted packet");
176 trace_block(T_PACKET, "tunnel: packet contents", BBASE(b), BLEN(b));
178 write(t->f.fd, BBASE(b), BLEN(b));
181 /* --- @tun_destroy@ --- *
183 * Arguments: @tunnel *t@ = pointer to tunnel block
187 * Use: Destroys a tunnel.
190 void tun_destroy(tunnel *t)
196 /*----- That's all, folks -------------------------------------------------*/