You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

750 lines
16 KiB

/*
* Copyright (c) 2001, Adam Dunkels.
* Copyright (c) 2009, Joakim Eriksson, Niclas Finne.
* 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, 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.
* 3. The name of the author may not be used to endorse or promote
* products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
*
* This file is part of the uIP TCP/IP stack.
*
*
*/
/* for cfmakeraw on Linux */
#define _BSD_SOURCE 1
#define _DEFAULT_SOURCE 1
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <time.h>
#include <sys/types.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <termios.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <err.h>
in_addr_t giaddr;
in_addr_t netaddr;
in_addr_t circuit_addr;
int ssystem(const char *fmt, ...) __attribute__((__format__(__printf__, 1, 2)));
void write_to_serial(int outfd, void *inbuf, int len);
//#define PROGRESS(s) fprintf(stderr, s)
#define PROGRESS(s) do { } while (0)
#define USAGE_STRING "usage: tapslip6 [-B baudrate] [-s siodev] [-t tundev] ipaddress netmask"
char tundev[1024] = { "tap0" };
int
ssystem(const char *fmt, ...) __attribute__((__format__(__printf__, 1, 2)));
int
ssystem(const char *fmt, ...)
{
char cmd[128];
va_list ap;
va_start(ap, fmt);
vsnprintf(cmd, sizeof(cmd), fmt, ap);
va_end(ap);
printf("%s\n", cmd);
fflush(stdout);
return system(cmd);
}
#define SLIP_END 0300
#define SLIP_ESC 0333
#define SLIP_ESC_END 0334
#define SLIP_ESC_ESC 0335
static void
print_packet(u_int8_t *p, int len)
{
int i;
for (i = 0; i < len; i++) {
printf("%02x", p[i]);
if ((i & 3) == 3) {
printf(" ");
}
if ((i & 15) == 15) {
printf("\n");
}
}
printf("\n");
}
int
is_sensible_string(const unsigned char *s, int len)
{
int i;
for (i = 1; i < len; i++) {
if (s[i] == 0 || s[i] == '\r' || s[i] == '\n' || s[i] == '\t') {
continue;
}
else if (s[i] < ' ' || '~' < s[i]) {
return 0;
}
}
return 1;
}
/*
* Read from serial, when we have a packet write it to tun. No output
* buffering, input buffered by stdio.
*/
void
serial_to_tun(FILE *inslip, int outfd)
{
static union {
unsigned char inbuf[2000];
} uip;
static int inbufptr = 0;
int ret;
unsigned char c;
#ifdef __linux__
ret = fread(&c, 1, 1, inslip);
if (ret == -1 || ret == 0) {
err(1, "serial_to_tun: read");
}
goto after_fread;
#endif
read_more:
if (inbufptr >= sizeof(uip.inbuf)) {
inbufptr = 0;
}
ret = fread(&c, 1, 1, inslip);
#ifdef __linux__
after_fread:
#endif
if (ret == -1) {
err(1, "serial_to_tun: read");
}
if (ret == 0) {
clearerr(inslip);
fprintf(stderr, "serial_to_tun: EOF\n");
exit(1);
}
/* fprintf(stderr, ".");*/
switch (c) {
case SLIP_END:
if (inbufptr > 0) {
if (uip.inbuf[0] == '!') {
if (uip.inbuf[1] == 'M') {
/* Read gateway MAC address and autoconfigure tap0 interface */
char macs[24];
int i, pos;
for (i = 0, pos = 0; i < 16; i++) {
macs[pos++] = uip.inbuf[2 + i];
if ((i & 1) == 1 && i < 14) {
macs[pos++] = ':';
}
}
macs[pos] = '\0';
printf("*** Gateway's MAC address: %s\n", macs);
ssystem("ifconfig %s down", tundev);
ssystem("ifconfig %s hw ether %s", tundev, &macs[6]);
ssystem("ifconfig %s up", tundev);
}
#define DEBUG_LINE_MARKER '\r'
}
else if (uip.inbuf[0] == DEBUG_LINE_MARKER) {
fwrite(uip.inbuf + 1, inbufptr - 1, 1, stdout);
}
else if (is_sensible_string(uip.inbuf, inbufptr)) {
fwrite(uip.inbuf, inbufptr, 1, stdout);
}
else {
printf("Writing to tun len: %d\n", inbufptr);
/* print_packet(uip.inbuf, inbufptr);*/
if (write(outfd, uip.inbuf, inbufptr) != inbufptr) {
err(1, "serial_to_tun: write");
}
}
inbufptr = 0;
}
break;
case SLIP_ESC:
if (fread(&c, 1, 1, inslip) != 1) {
clearerr(inslip);
/* Put ESC back and give up! */
ungetc(SLIP_ESC, inslip);
return;
}
switch (c) {
case SLIP_ESC_END:
c = SLIP_END;
break;
case SLIP_ESC_ESC:
c = SLIP_ESC;
break;
}
/* FALLTHROUGH */
default:
uip.inbuf[inbufptr++] = c;
break;
}
goto read_more;
}
unsigned char slip_buf[2000];
int slip_end, slip_begin;
void
slip_send(int fd, unsigned char c)
{
if (slip_end >= sizeof(slip_buf)) {
err(1, "slip_send overflow");
}
slip_buf[slip_end] = c;
slip_end++;
}
int
slip_empty()
{
return slip_end == 0;
}
void
slip_flushbuf(int fd)
{
int n;
if (slip_empty()) {
return;
}
n = write(fd, slip_buf + slip_begin, (slip_end - slip_begin));
if (n == -1 && errno != EAGAIN) {
err(1, "slip_flushbuf write failed");
}
else if (n == -1) {
PROGRESS("Q"); /* Outqueueis full! */
}
else {
slip_begin += n;
if (slip_begin == slip_end) {
slip_begin = slip_end = 0;
}
}
}
void
write_to_serial(int outfd, void *inbuf, int len)
{
u_int8_t *p = inbuf;
int i;
/* printf("Got packet of length %d - write SLIP\n", len);*/
/* print_packet(p, len);*/
/* It would be ``nice'' to send a SLIP_END here but it's not
* really necessary.
*/
/* slip_send(outfd, SLIP_END); */
/* printf("writing packet to serial!!!%d\n", len);*/
for (i = 0; i < len; i++) {
switch (p[i]) {
case SLIP_END:
slip_send(outfd, SLIP_ESC);
slip_send(outfd, SLIP_ESC_END);
break;
case SLIP_ESC:
slip_send(outfd, SLIP_ESC);
slip_send(outfd, SLIP_ESC_ESC);
break;
default:
slip_send(outfd, p[i]);
break;
}
}
slip_send(outfd, SLIP_END);
PROGRESS("t");
}
/*
* Read from tun, write to slip.
*/
void
tun_to_serial(int infd, int outfd)
{
struct {
unsigned char inbuf[2000];
} uip;
int size;
if ((size = read(infd, uip.inbuf, 2000)) == -1) {
err(1, "tun_to_serial: read");
}
write_to_serial(outfd, uip.inbuf, size);
}
#ifndef BAUDRATE
#define BAUDRATE B115200
#endif
speed_t b_rate = BAUDRATE;
void
stty_telos(int fd)
{
struct termios tty;
speed_t speed = b_rate;
int i;
if (tcflush(fd, TCIOFLUSH) == -1) {
err(1, "tcflush");
}
if (tcgetattr(fd, &tty) == -1) {
err(1, "tcgetattr");
}
cfmakeraw(&tty);
/* Nonblocking read. */
tty.c_cc[VTIME] = 0;
tty.c_cc[VMIN] = 0;
tty.c_cflag &= ~CRTSCTS;
tty.c_cflag &= ~HUPCL;
tty.c_cflag &= ~CLOCAL;
cfsetispeed(&tty, speed);
cfsetospeed(&tty, speed);
if (tcsetattr(fd, TCSAFLUSH, &tty) == -1) {
err(1, "tcsetattr");
}
#if 1
/* Nonblocking read and write. */
/* if (fcntl(fd, F_SETFL, O_NONBLOCK) == -1) err(1, "fcntl"); */
tty.c_cflag |= CLOCAL;
if (tcsetattr(fd, TCSAFLUSH, &tty) == -1) {
err(1, "tcsetattr");
}
i = TIOCM_DTR;
if (ioctl(fd, TIOCMBIS, &i) == -1) {
err(1, "ioctl");
}
#endif
usleep(10 * 1000); /* Wait for hardware 10ms. */
/* Flush input and output buffers. */
if (tcflush(fd, TCIOFLUSH) == -1) {
err(1, "tcflush");
}
}
int
devopen(const char *dev, int flags)
{
char t[1024];
strcpy(t, "/dev/");
strcat(t, dev);
return open(t, flags);
}
#ifdef __linux__
#include <linux/if.h>
#include <linux/if_tun.h>
int
tun_alloc(char *dev)
{
struct ifreq ifr;
int fd, err;
if ((fd = open("/dev/net/tun", O_RDWR)) < 0) {
return -1;
}
memset(&ifr, 0, sizeof(ifr));
/* Flags: IFF_TUN - TUN device (no Ethernet headers)
* IFF_TAP - TAP device
*
* IFF_NO_PI - Do not provide packet information
*/
ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
if (*dev != 0) {
strncpy(ifr.ifr_name, dev, IFNAMSIZ);
}
if ((err = ioctl(fd, TUNSETIFF, (void *) &ifr)) < 0) {
close(fd);
return err;
}
strcpy(dev, ifr.ifr_name);
return fd;
}
#else
int
tun_alloc(char *dev)
{
return devopen(dev, O_RDWR);
}
#endif
const char *ipaddr;
const char *netmask;
void
cleanup(void)
{
ssystem("ifconfig %s down", tundev);
#ifndef __linux__
ssystem("sysctl -w net.ipv6.conf.all.forwarding=1");
#endif
/* ssystem("arp -d %s", ipaddr); */
ssystem("netstat -nr"
" | awk '{ if ($2 == \"%s\") print \"route delete -net \"$1; }'"
" | sh",
tundev);
}
void
sigcleanup(int signo)
{
fprintf(stderr, "signal %d\n", signo);
exit(0); /* exit(0) will call cleanup() */
}
static int got_sigalarm;
static int request_mac;
void
sigalarm(int signo)
{
got_sigalarm = 1;
return;
}
void
sigalarm_reset()
{
#ifdef __linux__
#define TIMEOUT (997*1000)
#else
#define TIMEOUT (2451*1000)
#endif
ualarm(TIMEOUT, TIMEOUT);
got_sigalarm = 0;
}
void
ifconf(const char *tundev, const char *ipaddr, const char *netmask)
{
struct in_addr netname;
netname.s_addr = inet_addr(ipaddr) & inet_addr(netmask);
#ifdef __linux__
ssystem("ifconfig %s inet `hostname` up", tundev);
if (strcmp(ipaddr, "0.0.0.0") != 0) {
ssystem("route add -net %s netmask %s dev %s",
inet_ntoa(netname), netmask, tundev);
}
#else
ssystem("ifconfig %s inet `hostname` %s up", tundev, ipaddr);
if (strcmp(ipaddr, "0.0.0.0") != 0) {
ssystem("route add -net %s -netmask %s -interface %s",
inet_ntoa(netname), netmask, tundev);
}
ssystem("sysctl -w net.inet.ip.forwarding=1");
#endif /* !linux */
ssystem("ifconfig %s\n", tundev);
}
int
main(int argc, char **argv)
{
int c;
int tunfd, slipfd;
fd_set rset, wset;
FILE *inslip;
const char *siodev = NULL;
int baudrate = -2;
request_mac = 1;
setvbuf(stdout, NULL, _IOLBF, 0); /* Line buffered output. */
while ((c = getopt(argc, argv, "B:D:hs:t:")) != -1) {
switch (c) {
case 'B':
baudrate = atoi(optarg);
break;
case 's':
if (strncmp("/dev/", optarg, 5) == 0) {
siodev = optarg + 5;
}
else {
siodev = optarg;
}
break;
case 't':
if (strncmp("/dev/", optarg, 5) == 0) {
strcpy(tundev, optarg + 5);
}
else {
strcpy(tundev, optarg);
}
break;
case '?':
case 'h':
default:
errx(1, USAGE_STRING);
break;
}
}
argc -= (optind - 1);
argv += (optind - 1);
if (argc != 3 && argc != 4) {
errx(1, USAGE_STRING);
}
ipaddr = argv[1];
netmask = argv[2];
circuit_addr = inet_addr(ipaddr);
netaddr = inet_addr(ipaddr) & inet_addr(netmask);
switch (baudrate) {
case -2:
break; /* Use default. */
case 9600:
b_rate = B9600;
break;
case 19200:
b_rate = B19200;
break;
case 38400:
b_rate = B38400;
break;
case 57600:
b_rate = B57600;
break;
case 115200:
b_rate = B115200;
break;
default:
err(1, "unknown baudrate %d", baudrate);
break;
}
if (siodev != NULL) {
slipfd = devopen(siodev, O_RDWR | O_NONBLOCK);
if (slipfd == -1) {
err(1, "can't open siodev ``/dev/%s''", siodev);
}
}
else {
static const char *siodevs[] = {
"ttyUSB0", "cuaU0", "ucom0" /* linux, fbsd6, fbsd5 */
};
int i;
for (i = 0; i < 3; i++) {
siodev = siodevs[i];
slipfd = devopen(siodev, O_RDWR | O_NONBLOCK);
if (slipfd != -1) {
break;
}
}
if (slipfd == -1) {
err(1, "can't open siodev");
}
}
fprintf(stderr, "slip started on ``/dev/%s''\n", siodev);
stty_telos(slipfd);
slip_send(slipfd, SLIP_END);
inslip = fdopen(slipfd, "r");
if (inslip == NULL) {
err(1, "main: fdopen");
}
tunfd = tun_alloc(tundev);
printf("opening: %s", tundev);
if (tunfd == -1) {
err(1, "main: open");
}
fprintf(stderr, "opened device ``/dev/%s''\n", tundev);
atexit(cleanup);
signal(SIGHUP, sigcleanup);
signal(SIGTERM, sigcleanup);
signal(SIGINT, sigcleanup);
signal(SIGALRM, sigalarm);
ifconf(tundev, ipaddr, netmask);
while (1) {
int maxfd = 0;
FD_ZERO(&rset);
FD_ZERO(&wset);
/* request mac address from gateway node for autoconfiguration of
ethernet interface tap0 */
if (request_mac) {
slip_send(slipfd, '?');
slip_send(slipfd, 'M');
slip_send(slipfd, SLIP_END);
request_mac = 0;
}
if (got_sigalarm) {
/* Send "?IPA". */
slip_send(slipfd, '?');
slip_send(slipfd, 'I');
slip_send(slipfd, 'P');
slip_send(slipfd, 'A');
slip_send(slipfd, SLIP_END);
got_sigalarm = 0;
}
if (!slip_empty()) { /* Anything to flush? */
FD_SET(slipfd, &wset);
}
FD_SET(slipfd, &rset); /* Read from slip ASAP! */
if (slipfd > maxfd) {
maxfd = slipfd;
}
/* We only have one packet at a time queued for slip output. */
if (slip_empty()) {
FD_SET(tunfd, &rset);
if (tunfd > maxfd) {
maxfd = tunfd;
}
}
int ret = select(maxfd + 1, &rset, &wset, NULL, NULL);
if (ret == -1 && errno != EINTR) {
err(1, "select");
}
else if (ret > 0) {
if (FD_ISSET(slipfd, &rset)) {
serial_to_tun(inslip, tunfd);
}
if (FD_ISSET(slipfd, &wset)) {
slip_flushbuf(slipfd);
sigalarm_reset();
}
if (slip_empty() && FD_ISSET(tunfd, &rset)) {
tun_to_serial(tunfd, slipfd);
slip_flushbuf(slipfd);
sigalarm_reset();
}
}
}
}