nes-proj/arch/cpu/native/net/tun6-net.c
Niclas Finne 5c6117e698 Platform native: Avoid trying to use the tun when the tun is not available.
This allows a native platform application to run without network.
2017-11-02 01:32:51 +01:00

324 lines
8.1 KiB
C

/*
* Copyright (c) 2011, Swedish Institute of Computer Science.
* 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. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE 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 INSTITUTE 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.
*/
/**
* \author
* Niclas Finne <nfi@sics.se>
* Joakim Eriksson <joakime@sics.se>
*/
#include "net/ipv6/uip.h"
#include "net/ipv6/uip-ds6.h"
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <sys/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>
/* Log configuration */
#include "sys/log.h"
#define LOG_MODULE "Tun6"
#define LOG_LEVEL LOG_LEVEL_WARN
#ifdef linux
#include <linux/if.h>
#include <linux/if_tun.h>
#endif
#include <err.h>
#include "net/netstack.h"
#include "net/packetbuf.h"
static const char *config_ipaddr = "fd00::1/64";
/* Allocate some bytes in RAM and copy the string */
static char config_tundev[64] = "tun0";
#ifndef __CYGWIN__
static int tunfd = -1;
static int set_fd(fd_set *rset, fd_set *wset);
static void handle_fd(fd_set *rset, fd_set *wset);
static const struct select_callback tun_select_callback = {
set_fd,
handle_fd
};
#endif /* __CYGWIN__ */
static int ssystem(const char *fmt, ...)
__attribute__((__format__ (__printf__, 1, 2)));
static int
ssystem(const char *fmt, ...) __attribute__((__format__ (__printf__, 1, 2)));
int
static ssystem(const char *fmt, ...)
{
char cmd[128];
va_list ap;
va_start(ap, fmt);
vsnprintf(cmd, sizeof(cmd), fmt, ap);
va_end(ap);
LOG_INFO("%s\n", cmd);
fflush(stdout);
return system(cmd);
}
/*---------------------------------------------------------------------------*/
static void
cleanup(void)
{
ssystem("ifconfig %s down", config_tundev);
#ifndef linux
ssystem("sysctl -w net.ipv6.conf.all.forwarding=1");
#endif
ssystem("netstat -nr"
" | awk '{ if ($2 == \"%s\") print \"route delete -net \"$1; }'"
" | sh",
config_tundev);
}
/*---------------------------------------------------------------------------*/
static void
sigcleanup(int signo)
{
fprintf(stderr, "signal %d\n", signo);
exit(0); /* exit(0) will call cleanup() */
}
/*---------------------------------------------------------------------------*/
static void
ifconf(const char *tundev, const char *ipaddr)
{
#ifdef linux
ssystem("ifconfig %s inet `hostname` up", tundev);
ssystem("ifconfig %s add %s", tundev, ipaddr);
#elif defined(__APPLE__)
ssystem("ifconfig %s inet6 %s up", tundev, ipaddr);
ssystem("sysctl -w net.inet.ip.forwarding=1");
#else
ssystem("ifconfig %s inet `hostname` %s up", tundev, ipaddr);
ssystem("sysctl -w net.inet.ip.forwarding=1");
#endif /* !linux */
/* Print the configuration to the console. */
ssystem("ifconfig %s\n", tundev);
}
/*---------------------------------------------------------------------------*/
#ifdef linux
static int
tun_alloc(char *dev)
{
struct ifreq ifr;
int fd, err;
LOG_INFO("Opening: %s\n", dev);
if( (fd = open("/dev/net/tun", O_RDWR)) < 0 ) {
/* Error message handled by caller */
return -1;
}
memset(&ifr, 0, sizeof(ifr));
/* Flags: IFF_TUN - TUN device (no Ethernet headers)
* IFF_NO_PI - Do not provide packet information
*/
ifr.ifr_flags = IFF_TUN | IFF_NO_PI;
if(*dev != 0) {
strncpy(ifr.ifr_name, dev, IFNAMSIZ);
}
if((err = ioctl(fd, TUNSETIFF, (void *) &ifr)) < 0 ) {
/* Error message handled by caller */
close(fd);
return err;
}
LOG_INFO("Using '%s' vs '%s'\n", dev, ifr.ifr_name);
strncpy(dev, ifr.ifr_name, strlen(dev));
LOG_INFO("Using %s\n", dev);
return fd;
}
#else
static int
devopen(const char *dev, int flags)
{
char t[32];
strcpy(t, "/dev/");
strncat(t, dev, sizeof(t) - 5);
return open(t, flags);
}
/*---------------------------------------------------------------------------*/
static int
tun_alloc(char *dev)
{
LOG_INFO("Opening: %s\n", dev);
return devopen(dev, O_RDWR);
}
#endif
#ifdef __CYGWIN__
/*wpcap process is used to connect to host interface */
static void
tun_init()
{
setvbuf(stdout, NULL, _IOLBF, 0); /* Line buffered output. */
}
#else
/*---------------------------------------------------------------------------*/
static void
tun_init()
{
setvbuf(stdout, NULL, _IOLBF, 0); /* Line buffered output. */
LOG_INFO("Initializing tun interface\n");
tunfd = tun_alloc(config_tundev);
if(tunfd == -1) {
LOG_WARN("Failed to open tun device (you may be lacking permission). Running without network.\n");
/* err(1, "failed to allocate tun device ``%s''", config_tundev); */
return;
}
LOG_INFO("Tun open:%d\n", tunfd);
select_set_callback(tunfd, &tun_select_callback);
fprintf(stderr, "opened %s device ``/dev/%s''\n",
"tun", config_tundev);
atexit(cleanup);
signal(SIGHUP, sigcleanup);
signal(SIGTERM, sigcleanup);
signal(SIGINT, sigcleanup);
ifconf(config_tundev, config_ipaddr);
}
/*---------------------------------------------------------------------------*/
static int
tun_output(uint8_t *data, int len)
{
/* fprintf(stderr, "*** Writing to tun...%d\n", len); */
if(tunfd != -1 && write(tunfd, data, len) != len) {
err(1, "serial_to_tun: write");
return -1;
}
return 0;
}
/*---------------------------------------------------------------------------*/
static int
tun_input(unsigned char *data, int maxlen)
{
int size;
if(tunfd == -1) {
/* tun is not open */
return 0;
}
if((size = read(tunfd, data, maxlen)) == -1) {
err(1, "tun_input: read");
}
return size;
}
/*---------------------------------------------------------------------------*/
static uint8_t
output(const linkaddr_t *localdest)
{
LOG_DBG("SUT: %u\n", uip_len);
if(uip_len > 0) {
return tun_output(&uip_buf[UIP_LLH_LEN], uip_len);
}
return 0;
}
/*---------------------------------------------------------------------------*/
/* tun and slip select callback */
/*---------------------------------------------------------------------------*/
static int
set_fd(fd_set *rset, fd_set *wset)
{
if(tunfd == -1) {
return 0;
}
FD_SET(tunfd, rset);
return 1;
}
/*---------------------------------------------------------------------------*/
static void
handle_fd(fd_set *rset, fd_set *wset)
{
int size;
if(tunfd == -1) {
/* tun is not open */
return;
}
LOG_INFO("Tun6-handle FD\n");
if(FD_ISSET(tunfd, rset)) {
size = tun_input(&uip_buf[UIP_LLH_LEN], sizeof(uip_buf));
LOG_DBG("TUN data incoming read:%d\n", size);
uip_len = size;
tcpip_input();
}
}
#endif /* __CYGWIN_ */
static void input(void)
{
/* should not happen */
LOG_DBG("Tun6 - input\n");
}
const struct network_driver tun6_net_driver ={
"tun6",
tun_init,
input,
output
};
/*---------------------------------------------------------------------------*/