mirror of
https://github.com/freebsd/freebsd-src.git
synced 2024-11-29 19:43:41 +00:00
Program which implements "nos" alias "ka9q" alias "IP-IP" tunnels.
PR: 1154 Reviewed by: phk Manpage by: phk Submitted by: Nickolay N. Dudorov nnd@itfs.nsk.su
This commit is contained in:
Poul-Henning Kamp
parent
a2481bbe8e
commit
e66dbdb6c0
Notes:
svn2git
2020-12-20 02:59:44 +00:00
svn path=/head/; revision=35137
6
sbin/noc-tun/Makefile
Normal file
6
sbin/noc-tun/Makefile
Normal file
@ -0,0 +1,6 @@
|
||||
|
||||
PROG=nos-tun
|
||||
MAN8=nos-tun.8
|
||||
|
||||
.include <bsd.prog.mk>
|
||||
|
||||
73
sbin/noc-tun/nos-tun.8
Normal file
73
sbin/noc-tun/nos-tun.8
Normal file
@ -0,0 +1,73 @@
|
||||
.\"
|
||||
.\" ----------------------------------------------------------------------------
|
||||
.\" "THE BEER-WARE LICENSE" (Revision 42):
|
||||
.\" <phk@FreeBSD.org> wrote this file. As long as you retain this notice you
|
||||
.\" can do whatever you want with this stuff. If we meet some day, and you think
|
||||
.\" this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
|
||||
.\" ----------------------------------------------------------------------------
|
||||
.\"
|
||||
.\" $Id$
|
||||
.\"
|
||||
.Dd April 11, 1998
|
||||
.Dt NOS-TUN 8
|
||||
.Os FreeBSD 3.0
|
||||
.Sh NAME
|
||||
.Nm nos-tun
|
||||
.Nd Implement ``nos'' or ``ka9q'' style IP over IP tunnel
|
||||
.Sh SYNOPSIS
|
||||
.Nm nos-tun
|
||||
.Fl t
|
||||
.Ar tunnel
|
||||
.Fl s
|
||||
.Ar source
|
||||
.Fl d
|
||||
.Ar destination
|
||||
.Ar target
|
||||
.Sh DESCRIPTION
|
||||
.Nm
|
||||
is used to establish an
|
||||
.Em nos
|
||||
style tunnel, (also known as
|
||||
.Em ka9q
|
||||
or
|
||||
.Em IP-IP
|
||||
tunnel) using a
|
||||
.Xr tun 4
|
||||
kernel interface.
|
||||
.Pp
|
||||
.Ar tunnel
|
||||
is the name of the tunnel device
|
||||
.Dq /dev/tun0
|
||||
for example.
|
||||
.Pp
|
||||
.Ar source
|
||||
and
|
||||
.Ar destination
|
||||
are the addresses used on the tunnel device.
|
||||
If you configure the tunnel against a cisco router, use a netmask of
|
||||
.Dq 255.255.255.252
|
||||
on the cisco. This is because the tunnel is a point-to-point interface
|
||||
in the FreeBSD end, a concept cisco doesn't really implement.
|
||||
.Pp
|
||||
.Ar target
|
||||
is the address of the remote tunnel device, this must match the source
|
||||
address set on the remote end.
|
||||
.Sh EXAMPLES
|
||||
This end, a FreeBSD box on address 192.168.59.34:
|
||||
.Bd -literal -offset indent 4m
|
||||
nos-tun -t /dev/tun0 -s 192.168.61.1 -d 192.168.61.2 192.168.56.45
|
||||
.Ed
|
||||
.Pp
|
||||
Remote cisco on address 192.168.56.45:
|
||||
.Bd -literal -offset indent 4m
|
||||
interface tunnel 0
|
||||
ip address 192.168.61.2 255.255.255.252
|
||||
tunnel mode nos
|
||||
tunnel destination 192.168.59.34
|
||||
tunnel source 192.168.56.45
|
||||
.Ed
|
||||
.Sh BUGS
|
||||
We don't allow for setting our source address for multihomed machines.
|
||||
.Sh AUTHOR
|
||||
Nickolay N. Dudorov <nnd@itfs.nsk.su> wrote the program,
|
||||
Poul-Henning Kamp <phk@FreeBSD.org> wrote the man-page.
|
||||
345
sbin/noc-tun/nos-tun.c
Normal file
345
sbin/noc-tun/nos-tun.c
Normal file
@ -0,0 +1,345 @@
|
||||
/*
|
||||
* Copyright (c) 1996, Nickolay Dudorov
|
||||
* All rights reserved.
|
||||
*
|
||||
* Redistribution and use in source and binary forms, with or without
|
||||
* modification, are permitted provided that the following conditions
|
||||
* are met:
|
||||
* 1. Redistributions of source code must retain the above copyright
|
||||
* notice unmodified, this list of conditions, and the following
|
||||
* disclaimer.
|
||||
* 2. Redistributions in binary form must reproduce the above copyright
|
||||
* notice, this list of conditions and the following disclaimer in the
|
||||
* documentation and/or other materials provided with the distribution.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
||||
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||||
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
||||
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
||||
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
||||
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
||||
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
||||
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
||||
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
||||
* SUCH DAMAGE.
|
||||
*
|
||||
*/
|
||||
|
||||
/*
|
||||
* 'nos_tun' program configure tunN interface as a point-to-point
|
||||
* connection with two "pseudo"-addresses between this host and
|
||||
* 'target'.
|
||||
*
|
||||
* It uses Ip-over-Ip incapsulation ( protocol number 94 - IPIP)
|
||||
* (known as NOS-incapsulation in CISCO-routers' terminology).
|
||||
*
|
||||
* 'nos_tun' can works with itself and CISCO-routers.
|
||||
* (It may also work with Linux 'nos_tun's, but
|
||||
* I have no Linux system here to test with).
|
||||
*
|
||||
* BUGS (or features ?):
|
||||
* - you must specify ONE of the target host's addresses
|
||||
* ( nos_tun sends and accepts packets only to/from this
|
||||
* address )
|
||||
* - there can be only ONE tunnel between two hosts,
|
||||
* more precisely - between given host and (one of)
|
||||
* target hosts' address(es)
|
||||
* (and why do you want more ?)
|
||||
*/
|
||||
|
||||
|
||||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
#include <unistd.h>
|
||||
#include <string.h>
|
||||
#include <fcntl.h>
|
||||
#include <netdb.h>
|
||||
#include <syslog.h>
|
||||
#include <sys/param.h>
|
||||
#include <sys/socket.h>
|
||||
#include <sys/ioctl.h>
|
||||
#include <sys/signal.h>
|
||||
#include <sys/time.h>
|
||||
#include <netinet/in.h>
|
||||
#include <netinet/in_systm.h>
|
||||
#include <netinet/ip.h>
|
||||
#include <net/if.h>
|
||||
#include <arpa/inet.h>
|
||||
|
||||
|
||||
/* Tunnel interface configuration stuff */
|
||||
static struct ifaliasreq ifra;
|
||||
static struct ifreq ifrq;
|
||||
|
||||
/* Global descriptors */
|
||||
int net; /* socket descriptor */
|
||||
int tun; /* tunnel descriptor */
|
||||
|
||||
int Set_address(char *addr, struct sockaddr_in *sin)
|
||||
{
|
||||
struct hostent *hp;
|
||||
|
||||
bzero((char *)sin, sizeof(struct sockaddr));
|
||||
sin->sin_family = AF_INET;
|
||||
if((sin->sin_addr.s_addr = inet_addr(addr)) == (u_long)-1) {
|
||||
hp = gethostbyname(addr);
|
||||
if (!hp) {
|
||||
syslog(LOG_ERR,"Unknown host %s\n", addr);
|
||||
return 1;
|
||||
}
|
||||
sin->sin_family = hp->h_addrtype;
|
||||
bcopy(hp->h_addr, (caddr_t)&sin->sin_addr, hp->h_length);
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
int tun_open(char *devname, struct sockaddr *ouraddr, char *theiraddr)
|
||||
{
|
||||
int s;
|
||||
struct sockaddr_in *sin;
|
||||
|
||||
/* Open tun device */
|
||||
tun = open (devname, O_RDWR);
|
||||
if (tun < 0) {
|
||||
syslog(LOG_ERR,"Can't open %s - %m",devname);
|
||||
return(1);
|
||||
}
|
||||
|
||||
/*
|
||||
* At first, name the interface.
|
||||
*/
|
||||
bzero((char *)&ifra, sizeof(ifra));
|
||||
bzero((char *)&ifrq, sizeof(ifrq));
|
||||
|
||||
strncpy(ifrq.ifr_name, devname+5, IFNAMSIZ);
|
||||
strncpy(ifra.ifra_name, devname+5, IFNAMSIZ);
|
||||
|
||||
s = socket(AF_INET, SOCK_DGRAM, 0);
|
||||
if (s < 0) {
|
||||
syslog(LOG_ERR,"Can't open socket - %M");
|
||||
goto tunc_return;
|
||||
}
|
||||
|
||||
/*
|
||||
* Delete (previous) adresses for interface
|
||||
*
|
||||
* !!!!
|
||||
* On FreeBSD this ioctl returns error
|
||||
* when tunN have no addresses, so - log and ignore it.
|
||||
*
|
||||
*/
|
||||
if (ioctl(s, SIOCDIFADDR, &ifra) < 0) {
|
||||
syslog(LOG_ERR,"SIOCDIFADDR - %m");
|
||||
}
|
||||
|
||||
/*
|
||||
* Set interface address
|
||||
*/
|
||||
sin = (struct sockaddr_in *)&(ifra.ifra_addr);
|
||||
bcopy(ouraddr, sin, sizeof(struct sockaddr_in));
|
||||
sin->sin_len = sizeof(*sin);
|
||||
|
||||
/*
|
||||
* Set destination address
|
||||
*/
|
||||
sin = (struct sockaddr_in *)&(ifra.ifra_broadaddr);
|
||||
if(Set_address(theiraddr,sin)) {
|
||||
syslog(LOG_ERR,"Bad destination address:%s\n",theiraddr);
|
||||
goto stunc_return;
|
||||
}
|
||||
sin->sin_len = sizeof(*sin);
|
||||
|
||||
if (ioctl(s, SIOCAIFADDR, &ifra) < 0) {
|
||||
syslog(LOG_ERR,"Can't set interface address - %m");
|
||||
goto stunc_return;
|
||||
}
|
||||
|
||||
/*
|
||||
* Now, bring up the interface.
|
||||
*/
|
||||
if (ioctl(s, SIOCGIFFLAGS, &ifrq) < 0) {
|
||||
syslog(LOG_ERR,"Can't get interface flags - %m");
|
||||
goto stunc_return;
|
||||
}
|
||||
|
||||
ifrq.ifr_flags |= IFF_UP;
|
||||
if (!(ioctl(s, SIOCSIFFLAGS, &ifrq) < 0)) {
|
||||
close(s);
|
||||
return(0);
|
||||
}
|
||||
syslog(LOG_ERR,"Can't set interface UP - %m");
|
||||
stunc_return:
|
||||
close(s);
|
||||
tunc_return:
|
||||
close(tun);
|
||||
return(1);
|
||||
}
|
||||
|
||||
void Finish(int signum)
|
||||
{
|
||||
int s;
|
||||
|
||||
syslog(LOG_INFO,"Exiting");
|
||||
|
||||
close(net);
|
||||
|
||||
s = socket(AF_INET, SOCK_DGRAM, 0);
|
||||
if (s < 0) {
|
||||
syslog(LOG_ERR,"Can't open socket - %m");
|
||||
goto closing_tun;
|
||||
}
|
||||
|
||||
/*
|
||||
* Shut down interface.
|
||||
*/
|
||||
if (ioctl(s, SIOCGIFFLAGS, &ifrq) < 0) {
|
||||
syslog(LOG_ERR,"Can't get interface flags - %m");
|
||||
goto closing_fds;
|
||||
}
|
||||
|
||||
ifrq.ifr_flags &= ~(IFF_UP|IFF_RUNNING);
|
||||
if (ioctl(s, SIOCSIFFLAGS, &ifrq) < 0) {
|
||||
syslog(LOG_ERR,"Can't set interface DOWN - %m");
|
||||
goto closing_fds;
|
||||
}
|
||||
|
||||
/*
|
||||
* Delete adresses for interface
|
||||
*/
|
||||
bzero(&ifra.ifra_addr, sizeof(ifra.ifra_addr));
|
||||
bzero(&ifra.ifra_broadaddr, sizeof(ifra.ifra_addr));
|
||||
bzero(&ifra.ifra_mask, sizeof(ifra.ifra_addr));
|
||||
if (ioctl(s, SIOCDIFADDR, &ifra) < 0) {
|
||||
syslog(LOG_ERR,"Can't delete interface's addresses - %m");
|
||||
}
|
||||
closing_fds:
|
||||
close(s);
|
||||
closing_tun:
|
||||
close(tun);
|
||||
closelog();
|
||||
exit(signum);
|
||||
}
|
||||
|
||||
int main (int argc, char **argv)
|
||||
{
|
||||
int c, len, ipoff;
|
||||
|
||||
char *devname = NULL;
|
||||
char *point_to = NULL;
|
||||
char *to_point = NULL;
|
||||
char *target;
|
||||
|
||||
struct sockaddr t_laddr; /* Source address of tunnel */
|
||||
struct sockaddr whereto; /* Destination of tunnel */
|
||||
struct sockaddr_in *to;
|
||||
|
||||
char buf[0x2000]; /* Packets buffer */
|
||||
struct ip *ip = (struct ip *)buf;
|
||||
|
||||
fd_set rfds, wfds, efds; /* File descriptors for select() */
|
||||
int nfds; /* Return from select() */
|
||||
|
||||
|
||||
while ((c = getopt(argc, argv, "d:s:t:")) != EOF) {
|
||||
switch (c) {
|
||||
case 'd':
|
||||
to_point = optarg;
|
||||
break;
|
||||
case 's':
|
||||
point_to = optarg;
|
||||
break;
|
||||
case 't':
|
||||
devname = optarg;
|
||||
break;
|
||||
}
|
||||
}
|
||||
argc -= optind;
|
||||
argv += optind;
|
||||
|
||||
if (argc != 1 || (devname == NULL) ||
|
||||
(point_to == NULL) || (to_point == NULL)) {
|
||||
fprintf(stderr,
|
||||
"Usage: nos_tun -t <tun_name> -s <source_addr> -d <dest_addr> <target_addr>\n");
|
||||
exit(1);
|
||||
}
|
||||
|
||||
target = *argv;
|
||||
|
||||
/* Establish logging through 'syslog' */
|
||||
openlog("nos_tun", LOG_PID, LOG_DAEMON);
|
||||
|
||||
if(Set_address(point_to, (struct sockaddr_in *)&t_laddr)) {
|
||||
closelog();
|
||||
exit(2);
|
||||
}
|
||||
|
||||
if(tun_open(devname, &t_laddr, to_point)) {
|
||||
closelog();
|
||||
exit(3);
|
||||
}
|
||||
|
||||
to = (struct sockaddr_in *)&whereto;
|
||||
if(Set_address(target, to))
|
||||
Finish(4);
|
||||
|
||||
if ((net = socket(AF_INET, SOCK_RAW, 94)) < 0) {
|
||||
syslog(LOG_ERR,"Can't open socket - %m");
|
||||
Finish(5);
|
||||
}
|
||||
|
||||
if (connect(net,&whereto,sizeof(struct sockaddr_in)) < 0 ) {
|
||||
syslog(LOG_ERR,"Can't connect to target - %m");
|
||||
close(net);
|
||||
Finish(6);
|
||||
}
|
||||
|
||||
/* Demonize it */
|
||||
daemon(0,0);
|
||||
|
||||
/* Install signal handlers */
|
||||
(void)signal(SIGHUP,Finish);
|
||||
(void)signal(SIGINT,Finish);
|
||||
(void)signal(SIGTERM,Finish);
|
||||
|
||||
for (;;) {
|
||||
/* Set file descriptors for select() */
|
||||
FD_ZERO(&rfds); FD_ZERO(&wfds); FD_ZERO(&efds);
|
||||
FD_SET(tun,&rfds); FD_SET(net,&rfds);
|
||||
|
||||
nfds = select(net+10,&rfds,&wfds,&efds,NULL);
|
||||
if(nfds < 0) {
|
||||
syslog(LOG_ERR,"Interrupted select");
|
||||
close(net);
|
||||
Finish(7);
|
||||
}
|
||||
if(nfds == 0) { /* Impossible ? */
|
||||
syslog(LOG_ERR,"Timeout in select");
|
||||
close(net);
|
||||
Finish(8);
|
||||
}
|
||||
|
||||
|
||||
if(FD_ISSET(net,&rfds)) {
|
||||
/* Read from socket ... */
|
||||
len = read(net, buf, sizeof(buf));
|
||||
/* Check if this is "our" packet */
|
||||
if((ip->ip_src).s_addr == (to->sin_addr).s_addr) {
|
||||
/* ... skip encapsulation headers ... */
|
||||
ipoff = (ip->ip_hl << 2);
|
||||
/* ... and write to tun-device */
|
||||
write(tun,buf+ipoff,len-ipoff);
|
||||
}
|
||||
}
|
||||
|
||||
if(FD_ISSET(tun,&rfds)) {
|
||||
/* Read from tun ... */
|
||||
len = read(tun, buf, sizeof(buf));
|
||||
/* ... and send to network */
|
||||
if(send(net, buf, len,0) <= 0) {
|
||||
syslog(LOG_ERR,"Can't send - %m");
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
6
sbin/nos-tun/Makefile
Normal file
6
sbin/nos-tun/Makefile
Normal file
@ -0,0 +1,6 @@
|
||||
|
||||
PROG=nos-tun
|
||||
MAN8=nos-tun.8
|
||||
|
||||
.include <bsd.prog.mk>
|
||||
|
||||
73
sbin/nos-tun/nos-tun.8
Normal file
73
sbin/nos-tun/nos-tun.8
Normal file
@ -0,0 +1,73 @@
|
||||
.\"
|
||||
.\" ----------------------------------------------------------------------------
|
||||
.\" "THE BEER-WARE LICENSE" (Revision 42):
|
||||
.\" <phk@FreeBSD.org> wrote this file. As long as you retain this notice you
|
||||
.\" can do whatever you want with this stuff. If we meet some day, and you think
|
||||
.\" this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
|
||||
.\" ----------------------------------------------------------------------------
|
||||
.\"
|
||||
.\" $Id$
|
||||
.\"
|
||||
.Dd April 11, 1998
|
||||
.Dt NOS-TUN 8
|
||||
.Os FreeBSD 3.0
|
||||
.Sh NAME
|
||||
.Nm nos-tun
|
||||
.Nd Implement ``nos'' or ``ka9q'' style IP over IP tunnel
|
||||
.Sh SYNOPSIS
|
||||
.Nm nos-tun
|
||||
.Fl t
|
||||
.Ar tunnel
|
||||
.Fl s
|
||||
.Ar source
|
||||
.Fl d
|
||||
.Ar destination
|
||||
.Ar target
|
||||
.Sh DESCRIPTION
|
||||
.Nm
|
||||
is used to establish an
|
||||
.Em nos
|
||||
style tunnel, (also known as
|
||||
.Em ka9q
|
||||
or
|
||||
.Em IP-IP
|
||||
tunnel) using a
|
||||
.Xr tun 4
|
||||
kernel interface.
|
||||
.Pp
|
||||
.Ar tunnel
|
||||
is the name of the tunnel device
|
||||
.Dq /dev/tun0
|
||||
for example.
|
||||
.Pp
|
||||
.Ar source
|
||||
and
|
||||
.Ar destination
|
||||
are the addresses used on the tunnel device.
|
||||
If you configure the tunnel against a cisco router, use a netmask of
|
||||
.Dq 255.255.255.252
|
||||
on the cisco. This is because the tunnel is a point-to-point interface
|
||||
in the FreeBSD end, a concept cisco doesn't really implement.
|
||||
.Pp
|
||||
.Ar target
|
||||
is the address of the remote tunnel device, this must match the source
|
||||
address set on the remote end.
|
||||
.Sh EXAMPLES
|
||||
This end, a FreeBSD box on address 192.168.59.34:
|
||||
.Bd -literal -offset indent 4m
|
||||
nos-tun -t /dev/tun0 -s 192.168.61.1 -d 192.168.61.2 192.168.56.45
|
||||
.Ed
|
||||
.Pp
|
||||
Remote cisco on address 192.168.56.45:
|
||||
.Bd -literal -offset indent 4m
|
||||
interface tunnel 0
|
||||
ip address 192.168.61.2 255.255.255.252
|
||||
tunnel mode nos
|
||||
tunnel destination 192.168.59.34
|
||||
tunnel source 192.168.56.45
|
||||
.Ed
|
||||
.Sh BUGS
|
||||
We don't allow for setting our source address for multihomed machines.
|
||||
.Sh AUTHOR
|
||||
Nickolay N. Dudorov <nnd@itfs.nsk.su> wrote the program,
|
||||
Poul-Henning Kamp <phk@FreeBSD.org> wrote the man-page.
|
||||
345
sbin/nos-tun/nos-tun.c
Normal file
345
sbin/nos-tun/nos-tun.c
Normal file
@ -0,0 +1,345 @@
|
||||
/*
|
||||
* Copyright (c) 1996, Nickolay Dudorov
|
||||
* All rights reserved.
|
||||
*
|
||||
* Redistribution and use in source and binary forms, with or without
|
||||
* modification, are permitted provided that the following conditions
|
||||
* are met:
|
||||
* 1. Redistributions of source code must retain the above copyright
|
||||
* notice unmodified, this list of conditions, and the following
|
||||
* disclaimer.
|
||||
* 2. Redistributions in binary form must reproduce the above copyright
|
||||
* notice, this list of conditions and the following disclaimer in the
|
||||
* documentation and/or other materials provided with the distribution.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
||||
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||||
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
||||
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
||||
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
||||
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
||||
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
||||
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
||||
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
||||
* SUCH DAMAGE.
|
||||
*
|
||||
*/
|
||||
|
||||
/*
|
||||
* 'nos_tun' program configure tunN interface as a point-to-point
|
||||
* connection with two "pseudo"-addresses between this host and
|
||||
* 'target'.
|
||||
*
|
||||
* It uses Ip-over-Ip incapsulation ( protocol number 94 - IPIP)
|
||||
* (known as NOS-incapsulation in CISCO-routers' terminology).
|
||||
*
|
||||
* 'nos_tun' can works with itself and CISCO-routers.
|
||||
* (It may also work with Linux 'nos_tun's, but
|
||||
* I have no Linux system here to test with).
|
||||
*
|
||||
* BUGS (or features ?):
|
||||
* - you must specify ONE of the target host's addresses
|
||||
* ( nos_tun sends and accepts packets only to/from this
|
||||
* address )
|
||||
* - there can be only ONE tunnel between two hosts,
|
||||
* more precisely - between given host and (one of)
|
||||
* target hosts' address(es)
|
||||
* (and why do you want more ?)
|
||||
*/
|
||||
|
||||
|
||||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
#include <unistd.h>
|
||||
#include <string.h>
|
||||
#include <fcntl.h>
|
||||
#include <netdb.h>
|
||||
#include <syslog.h>
|
||||
#include <sys/param.h>
|
||||
#include <sys/socket.h>
|
||||
#include <sys/ioctl.h>
|
||||
#include <sys/signal.h>
|
||||
#include <sys/time.h>
|
||||
#include <netinet/in.h>
|
||||
#include <netinet/in_systm.h>
|
||||
#include <netinet/ip.h>
|
||||
#include <net/if.h>
|
||||
#include <arpa/inet.h>
|
||||
|
||||
|
||||
/* Tunnel interface configuration stuff */
|
||||
static struct ifaliasreq ifra;
|
||||
static struct ifreq ifrq;
|
||||
|
||||
/* Global descriptors */
|
||||
int net; /* socket descriptor */
|
||||
int tun; /* tunnel descriptor */
|
||||
|
||||
int Set_address(char *addr, struct sockaddr_in *sin)
|
||||
{
|
||||
struct hostent *hp;
|
||||
|
||||
bzero((char *)sin, sizeof(struct sockaddr));
|
||||
sin->sin_family = AF_INET;
|
||||
if((sin->sin_addr.s_addr = inet_addr(addr)) == (u_long)-1) {
|
||||
hp = gethostbyname(addr);
|
||||
if (!hp) {
|
||||
syslog(LOG_ERR,"Unknown host %s\n", addr);
|
||||
return 1;
|
||||
}
|
||||
sin->sin_family = hp->h_addrtype;
|
||||
bcopy(hp->h_addr, (caddr_t)&sin->sin_addr, hp->h_length);
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
int tun_open(char *devname, struct sockaddr *ouraddr, char *theiraddr)
|
||||
{
|
||||
int s;
|
||||
struct sockaddr_in *sin;
|
||||
|
||||
/* Open tun device */
|
||||
tun = open (devname, O_RDWR);
|
||||
if (tun < 0) {
|
||||
syslog(LOG_ERR,"Can't open %s - %m",devname);
|
||||
return(1);
|
||||
}
|
||||
|
||||
/*
|
||||
* At first, name the interface.
|
||||
*/
|
||||
bzero((char *)&ifra, sizeof(ifra));
|
||||
bzero((char *)&ifrq, sizeof(ifrq));
|
||||
|
||||
strncpy(ifrq.ifr_name, devname+5, IFNAMSIZ);
|
||||
strncpy(ifra.ifra_name, devname+5, IFNAMSIZ);
|
||||
|
||||
s = socket(AF_INET, SOCK_DGRAM, 0);
|
||||
if (s < 0) {
|
||||
syslog(LOG_ERR,"Can't open socket - %M");
|
||||
goto tunc_return;
|
||||
}
|
||||
|
||||
/*
|
||||
* Delete (previous) adresses for interface
|
||||
*
|
||||
* !!!!
|
||||
* On FreeBSD this ioctl returns error
|
||||
* when tunN have no addresses, so - log and ignore it.
|
||||
*
|
||||
*/
|
||||
if (ioctl(s, SIOCDIFADDR, &ifra) < 0) {
|
||||
syslog(LOG_ERR,"SIOCDIFADDR - %m");
|
||||
}
|
||||
|
||||
/*
|
||||
* Set interface address
|
||||
*/
|
||||
sin = (struct sockaddr_in *)&(ifra.ifra_addr);
|
||||
bcopy(ouraddr, sin, sizeof(struct sockaddr_in));
|
||||
sin->sin_len = sizeof(*sin);
|
||||
|
||||
/*
|
||||
* Set destination address
|
||||
*/
|
||||
sin = (struct sockaddr_in *)&(ifra.ifra_broadaddr);
|
||||
if(Set_address(theiraddr,sin)) {
|
||||
syslog(LOG_ERR,"Bad destination address:%s\n",theiraddr);
|
||||
goto stunc_return;
|
||||
}
|
||||
sin->sin_len = sizeof(*sin);
|
||||
|
||||
if (ioctl(s, SIOCAIFADDR, &ifra) < 0) {
|
||||
syslog(LOG_ERR,"Can't set interface address - %m");
|
||||
goto stunc_return;
|
||||
}
|
||||
|
||||
/*
|
||||
* Now, bring up the interface.
|
||||
*/
|
||||
if (ioctl(s, SIOCGIFFLAGS, &ifrq) < 0) {
|
||||
syslog(LOG_ERR,"Can't get interface flags - %m");
|
||||
goto stunc_return;
|
||||
}
|
||||
|
||||
ifrq.ifr_flags |= IFF_UP;
|
||||
if (!(ioctl(s, SIOCSIFFLAGS, &ifrq) < 0)) {
|
||||
close(s);
|
||||
return(0);
|
||||
}
|
||||
syslog(LOG_ERR,"Can't set interface UP - %m");
|
||||
stunc_return:
|
||||
close(s);
|
||||
tunc_return:
|
||||
close(tun);
|
||||
return(1);
|
||||
}
|
||||
|
||||
void Finish(int signum)
|
||||
{
|
||||
int s;
|
||||
|
||||
syslog(LOG_INFO,"Exiting");
|
||||
|
||||
close(net);
|
||||
|
||||
s = socket(AF_INET, SOCK_DGRAM, 0);
|
||||
if (s < 0) {
|
||||
syslog(LOG_ERR,"Can't open socket - %m");
|
||||
goto closing_tun;
|
||||
}
|
||||
|
||||
/*
|
||||
* Shut down interface.
|
||||
*/
|
||||
if (ioctl(s, SIOCGIFFLAGS, &ifrq) < 0) {
|
||||
syslog(LOG_ERR,"Can't get interface flags - %m");
|
||||
goto closing_fds;
|
||||
}
|
||||
|
||||
ifrq.ifr_flags &= ~(IFF_UP|IFF_RUNNING);
|
||||
if (ioctl(s, SIOCSIFFLAGS, &ifrq) < 0) {
|
||||
syslog(LOG_ERR,"Can't set interface DOWN - %m");
|
||||
goto closing_fds;
|
||||
}
|
||||
|
||||
/*
|
||||
* Delete adresses for interface
|
||||
*/
|
||||
bzero(&ifra.ifra_addr, sizeof(ifra.ifra_addr));
|
||||
bzero(&ifra.ifra_broadaddr, sizeof(ifra.ifra_addr));
|
||||
bzero(&ifra.ifra_mask, sizeof(ifra.ifra_addr));
|
||||
if (ioctl(s, SIOCDIFADDR, &ifra) < 0) {
|
||||
syslog(LOG_ERR,"Can't delete interface's addresses - %m");
|
||||
}
|
||||
closing_fds:
|
||||
close(s);
|
||||
closing_tun:
|
||||
close(tun);
|
||||
closelog();
|
||||
exit(signum);
|
||||
}
|
||||
|
||||
int main (int argc, char **argv)
|
||||
{
|
||||
int c, len, ipoff;
|
||||
|
||||
char *devname = NULL;
|
||||
char *point_to = NULL;
|
||||
char *to_point = NULL;
|
||||
char *target;
|
||||
|
||||
struct sockaddr t_laddr; /* Source address of tunnel */
|
||||
struct sockaddr whereto; /* Destination of tunnel */
|
||||
struct sockaddr_in *to;
|
||||
|
||||
char buf[0x2000]; /* Packets buffer */
|
||||
struct ip *ip = (struct ip *)buf;
|
||||
|
||||
fd_set rfds, wfds, efds; /* File descriptors for select() */
|
||||
int nfds; /* Return from select() */
|
||||
|
||||
|
||||
while ((c = getopt(argc, argv, "d:s:t:")) != EOF) {
|
||||
switch (c) {
|
||||
case 'd':
|
||||
to_point = optarg;
|
||||
break;
|
||||
case 's':
|
||||
point_to = optarg;
|
||||
break;
|
||||
case 't':
|
||||
devname = optarg;
|
||||
break;
|
||||
}
|
||||
}
|
||||
argc -= optind;
|
||||
argv += optind;
|
||||
|
||||
if (argc != 1 || (devname == NULL) ||
|
||||
(point_to == NULL) || (to_point == NULL)) {
|
||||
fprintf(stderr,
|
||||
"Usage: nos_tun -t <tun_name> -s <source_addr> -d <dest_addr> <target_addr>\n");
|
||||
exit(1);
|
||||
}
|
||||
|
||||
target = *argv;
|
||||
|
||||
/* Establish logging through 'syslog' */
|
||||
openlog("nos_tun", LOG_PID, LOG_DAEMON);
|
||||
|
||||
if(Set_address(point_to, (struct sockaddr_in *)&t_laddr)) {
|
||||
closelog();
|
||||
exit(2);
|
||||
}
|
||||
|
||||
if(tun_open(devname, &t_laddr, to_point)) {
|
||||
closelog();
|
||||
exit(3);
|
||||
}
|
||||
|
||||
to = (struct sockaddr_in *)&whereto;
|
||||
if(Set_address(target, to))
|
||||
Finish(4);
|
||||
|
||||
if ((net = socket(AF_INET, SOCK_RAW, 94)) < 0) {
|
||||
syslog(LOG_ERR,"Can't open socket - %m");
|
||||
Finish(5);
|
||||
}
|
||||
|
||||
if (connect(net,&whereto,sizeof(struct sockaddr_in)) < 0 ) {
|
||||
syslog(LOG_ERR,"Can't connect to target - %m");
|
||||
close(net);
|
||||
Finish(6);
|
||||
}
|
||||
|
||||
/* Demonize it */
|
||||
daemon(0,0);
|
||||
|
||||
/* Install signal handlers */
|
||||
(void)signal(SIGHUP,Finish);
|
||||
(void)signal(SIGINT,Finish);
|
||||
(void)signal(SIGTERM,Finish);
|
||||
|
||||
for (;;) {
|
||||
/* Set file descriptors for select() */
|
||||
FD_ZERO(&rfds); FD_ZERO(&wfds); FD_ZERO(&efds);
|
||||
FD_SET(tun,&rfds); FD_SET(net,&rfds);
|
||||
|
||||
nfds = select(net+10,&rfds,&wfds,&efds,NULL);
|
||||
if(nfds < 0) {
|
||||
syslog(LOG_ERR,"Interrupted select");
|
||||
close(net);
|
||||
Finish(7);
|
||||
}
|
||||
if(nfds == 0) { /* Impossible ? */
|
||||
syslog(LOG_ERR,"Timeout in select");
|
||||
close(net);
|
||||
Finish(8);
|
||||
}
|
||||
|
||||
|
||||
if(FD_ISSET(net,&rfds)) {
|
||||
/* Read from socket ... */
|
||||
len = read(net, buf, sizeof(buf));
|
||||
/* Check if this is "our" packet */
|
||||
if((ip->ip_src).s_addr == (to->sin_addr).s_addr) {
|
||||
/* ... skip encapsulation headers ... */
|
||||
ipoff = (ip->ip_hl << 2);
|
||||
/* ... and write to tun-device */
|
||||
write(tun,buf+ipoff,len-ipoff);
|
||||
}
|
||||
}
|
||||
|
||||
if(FD_ISSET(tun,&rfds)) {
|
||||
/* Read from tun ... */
|
||||
len = read(tun, buf, sizeof(buf));
|
||||
/* ... and send to network */
|
||||
if(send(net, buf, len,0) <= 0) {
|
||||
syslog(LOG_ERR,"Can't send - %m");
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user