4 * uAnytun is a tiny implementation of SATP. Unlike Anytun which is a full
5 * featured implementation uAnytun has no support for multiple connections
6 * or synchronisation. It is a small single threaded implementation intended
7 * to act as a client on small platforms.
8 * The secure anycast tunneling protocol (satp) defines a protocol used
9 * for communication between any combination of unicast and anycast
10 * tunnel endpoints. It has less protocol overhead than IPSec in Tunnel
11 * mode and allows tunneling of every ETHER TYPE protocol (e.g.
12 * ethernet, ip, arp ...). satp directly includes cryptography and
13 * message authentication based on the methods used by SRTP. It is
14 * intended to deliver a generic, scaleable and secure solution for
15 * tunneling and relaying of packets of any protocol.
18 * Copyright (C) 2007-2014 Christian Pointner <equinox@anytun.org>
20 * This file is part of uAnytun.
22 * uAnytun is free software: you can redistribute it and/or modify
23 * it under the terms of the GNU General Public License as published by
24 * the Free Software Foundation, either version 3 of the License, or
27 * uAnytun is distributed in the hope that it will be useful,
28 * but WITHOUT ANY WARRANTY; without even the implied warranty of
29 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
30 * GNU General Public License for more details.
32 * You should have received a copy of the GNU General Public License
33 * along with uAnytun. If not, see <http://www.gnu.org/licenses/>.
35 * In addition, as a special exception, the copyright holders give
36 * permission to link the code of portions of this program with the
37 * OpenSSL library under certain conditions as described in each
38 * individual source file, and distribute linked combinations
40 * You must obey the GNU General Public License in all respects
41 * for all of the code used other than OpenSSL. If you modify
42 * file(s) with this exception, you may extend this exception to your
43 * version of the file(s), but you are not obligated to do so. If you
44 * do not wish to do so, delete this exception statement from your
45 * version. If you delete this exception statement from all source
46 * files in the program, then also delete it here.
52 #include "datatypes.h"
56 #include "tun_helper.h"
62 #include <sys/ioctl.h>
63 #include <arpa/inet.h>
67 #include <linux/if_ether.h>
68 #include <linux/if_tun.h>
69 #define DEFAULT_DEVICE "/dev/net/tun"
74 int tun_init(tun_device_t* dev, const char* dev_name, const char* dev_type, const char* ifcfg_addr, u_int16_t ifcfg_prefix){
78 tun_conf(dev, dev_name, dev_type, ifcfg_addr, ifcfg_prefix, 1400);
79 dev->actual_name_ = NULL;
81 dev->fd_ = open(DEFAULT_DEVICE, O_RDWR);
83 log_printf(ERROR, "can't open device file (%s): %s", DEFAULT_DEVICE, strerror(errno));
89 memset(&ifr, 0, sizeof(ifr));
91 if(dev->type_ == TYPE_TUN) {
92 ifr.ifr_flags = IFF_TUN;
95 else if(dev->type_ == TYPE_TAP) {
96 ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
100 log_printf(ERROR, "unable to recognize type of device (tun or tap)");
106 strncpy(ifr.ifr_name, dev_name, IFNAMSIZ);
108 if(!ioctl(dev->fd_, TUNSETIFF, &ifr)) {
109 dev->actual_name_ = strdup(ifr.ifr_name);
110 } else if(!ioctl(dev->fd_, (('T' << 8) | 202), &ifr)) {
111 dev->actual_name_ = strdup(ifr.ifr_name);
113 log_printf(ERROR, "tun/tap device ioctl failed: %s", strerror(errno));
118 if(!dev->actual_name_) {
119 log_printf(ERROR, "can't open device file: memory error");
125 tun_do_ifconfig(dev);
130 int tun_init_post(tun_device_t* dev)
136 void tun_close(tun_device_t* dev)
144 if(dev->actual_name_)
145 free(dev->actual_name_);
148 free(dev->net_addr_);
151 free(dev->net_mask_);
154 int tun_read(tun_device_t* dev, u_int8_t* buf, u_int32_t len)
156 if(!dev || dev->fd_ < 0)
164 iov[0].iov_base = &tpi;
165 iov[0].iov_len = sizeof(tpi);
166 iov[1].iov_base = buf;
167 iov[1].iov_len = len;
168 return(tun_fix_return(readv(dev->fd_, iov, 2), sizeof(tpi)));
171 return(read(dev->fd_, buf, len));
174 int tun_write(tun_device_t* dev, u_int8_t* buf, u_int32_t len)
176 if(!dev || dev->fd_ < 0)
186 struct iphdr *hdr = (struct iphdr *)buf;
189 if(hdr->version == 4)
190 tpi.proto = htons(ETH_P_IP);
192 tpi.proto = htons(ETH_P_IPV6);
194 iov[0].iov_base = &tpi;
195 iov[0].iov_len = sizeof(tpi);
196 iov[1].iov_base = buf;
197 iov[1].iov_len = len;
198 return(tun_fix_return(writev(dev->fd_, iov, 2), sizeof(tpi)));
201 return(write(dev->fd_, buf, len));
204 void tun_do_ifconfig(tun_device_t* dev)
206 if(!dev || !dev->actual_name_ || !dev->net_addr_ || !dev->net_mask_)
209 char* mtu_str = NULL;
210 int len = asprintf(&mtu_str, "%d", dev->mtu_);
212 log_printf(ERROR, "Execution of ifconfig failed");
216 char* const argv[] = { "/sbin/ifconfig", dev->actual_name_, dev->net_addr_, "netmask", dev->net_mask_, "mtu", mtu_str, NULL };
217 char* const evp[] = { NULL };
218 uanytun_exec("/sbin/ifconfig", argv, evp);