Bochs/bochs/iodev/eth_tuntap.cc
Christophe Bothamy 980364868d - added a script directive in ne2k options of .bochsrc
- added the script directive management for ne2k options
- added the execution of the script (if defined and not 'none') after init of the tun device
2002-05-02 07:54:22 +00:00

424 lines
13 KiB
C++

/////////////////////////////////////////////////////////////////////////
// $Id: eth_tuntap.cc,v 1.3 2002-05-02 07:54:22 cbothamy Exp $
/////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2001 MandrakeSoft S.A.
//
// MandrakeSoft S.A.
// 43, rue d'Aboukir
// 75002 Paris - France
// http://www.linux-mandrake.com/
// http://www.mandrakesoft.com/
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
// eth_tuntap.cc - TUN/TAP interface by Renzo Davoli <renzo@cs.unibo.it>
//
// WARNING: These instructions were written for ethertap, not TUN/TAP.
//
// Here's how to get this working. On the host machine:
// $ su root
// # /sbin/insmod ethertap
// Using /lib/modules/2.2.14-5.0/net/ethertap.o
// # mknod /dev/tap0 c 36 16 # if not already there
// # /sbin/ifconfig tap0 10.0.0.1
// # /sbin/route add -host 10.0.0.2 gw 10.0.0.1
//
// Now you have a tap0 device which you can on the ifconfig output. The
// tap0 interface has the IP address of 10.0.0.1. The bochs machine will have
// the IP address 10.0.0.2.
//
// Compile a bochs version from March 8, 2002 or later with --enable-ne2000.
// Add this ne2k line to your .bochsrc to activate the tap device.
// ne2k: ioaddr=0x280, irq=9, mac=fe:fd:00:00:00:01, ethmod=tap, ethdev=tap0
// Don't change the mac or ethmod!
//
// Boot up DLX Linux in Bochs. Log in as root and then type the following
// commands to set up networking:
// # ifconfig eth0 10.0.0.2
// # route add -net 10.0.0.0
// # route add default gw 10.0.0.1
// Now you should be able to ping from guest OS to your host machine, if
// you give its IP number. I'm still having trouble with pings from the
// host machine to the guest, so something is still not right. Symptoms: I
// ping from the host to the guest's IP address 10.0.0.2. With tcpdump I can
// see the ping going to Bochs, and then the ping reply coming from Bochs.
// But the ping program itself does not see the responses....well every
// once in a while it does, like 1 in 60 pings.
//
// host$ ping 10.0.0.2
// PING 10.0.0.2 (10.0.0.2) from 10.0.0.1 : 56(84) bytes of data.
//
// Netstat output:
// 20:29:59.018776 fe:fd:0:0:0:0 fe:fd:0:0:0:1 0800 98: 10.0.0.1 > 10.0.0.2: icmp: echo request
// 4500 0054 2800 0000 4001 3ea7 0a00 0001
// 0a00 0002 0800 09d3 a53e 0400 9765 893c
// 3949 0000 0809 0a0b 0c0d 0e0f 1011 1213
// 1415 1617 1819
// 20:29:59.023017 fe:fd:0:0:0:1 fe:fd:0:0:0:0 0800 98: 10.0.0.2 > 10.0.0.1: icmp: echo reply
// 4500 0054 004a 0000 4001 665d 0a00 0002
// 0a00 0001 0000 11d3 a53e 0400 9765 893c
// 3949 0000 0809 0a0b 0c0d 0e0f 1011 1213
// 1415 1617 1819
//
// I suspect it may be related to the fact that ping 10.0.0.1 from the
// host also doesn't work. Why wouldn't the host respond to its own IP
// address on the tap0 device?
//
// Theoretically, if you set up packet forwarding (with masquerading) on the
// host, you should be able to get Bochs talking to anyone on the internet.
//
#include "bochs.h"
#define LOG_THIS bx_ne2k.
#include <signal.h>
#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/poll.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <asm/types.h>
#include <sys/socket.h>
#include <sys/uio.h>
#include <sys/wait.h>
#include <linux/netlink.h>
#include <linux/if.h>
#include <linux/if_tun.h>
#include <assert.h>
#include <fcntl.h>
#include <errno.h>
#define TUNTAP_VIRTUAL_HW_ADDR 0xDEADBEEF
#define BX_ETH_TUNTAP_LOGGING 0
#define BX_PACKET_BUFSIZ 2048 // Enough for an ether frame
int tun_alloc(char *dev);
int execute_script(char *name, char* arg1);
//
// Define the class. This is private to this module
//
class bx_tuntap_pktmover_c : public eth_pktmover_c {
public:
bx_tuntap_pktmover_c(const char *netif, const char *macaddr,
eth_rx_handler_t rxh,
void *rxarg);
void sendpkt(void *buf, unsigned io_len);
private:
int fd;
int rx_timer_index;
static void rx_timer_handler(void *);
void rx_timer ();
FILE *txlog, *txlog_txt, *rxlog, *rxlog_txt;
};
//
// Define the static class that registers the derived pktmover class,
// and allocates one on request.
//
class bx_tuntap_locator_c : public eth_locator_c {
public:
bx_tuntap_locator_c(void) : eth_locator_c("tuntap") {}
protected:
eth_pktmover_c *allocate(const char *netif, const char *macaddr,
eth_rx_handler_t rxh,
void *rxarg) {
return (new bx_tuntap_pktmover_c(netif, macaddr, rxh, rxarg));
}
} bx_tuntap_match;
//
// Define the methods for the bx_tuntap_pktmover derived class
//
// the constructor
bx_tuntap_pktmover_c::bx_tuntap_pktmover_c(const char *netif,
const char *macaddr,
eth_rx_handler_t rxh,
void *rxarg)
{
int flags;
char filename[BX_PATHNAME_LEN];
if (strncmp (netif, "tun", 3) != 0) {
BX_PANIC (("eth_tuntap: interface name (%s) must be tun", netif));
}
#ifdef NEVERDEF
sprintf (filename, "/dev/net/%s", netif);
// check if the TUN/TAP devices is running, and turn on ARP. This is based
// on code from the Mac-On-Linux project. http://http://www.maconlinux.org/
int sock = socket( AF_INET, SOCK_DGRAM, 0 );
if (sock < 0) {
BX_PANIC (("socket creation: %s", strerror(errno)));
return;
}
struct ifreq ifr;
memset( &ifr, 0, sizeof(ifr) );
strncpy( ifr.ifr_name, netif, sizeof(ifr.ifr_name) );
if( ioctl( sock, SIOCGIFFLAGS, &ifr ) < 0 ){
BX_PANIC (("SIOCGIFFLAGS on %s: %s", netif, strerror (errno)));
close(sock);
return;
}
if( !(ifr.ifr_flags & IFF_RUNNING ) ){
BX_PANIC (("%s device is not running", netif));
close(sock);
return;
}
if( (ifr.ifr_flags & IFF_NOARP ) ){
BX_INFO (("turn on ARP for %s device", netif));
ifr.ifr_flags &= ~IFF_NOARP;
if( ioctl( sock, SIOCSIFFLAGS, &ifr ) < 0 ) {
BX_PANIC (("SIOCSIFFLAGS: %s", strerror(errno)));
close(sock);
return;
}
}
close(sock);
fd = open (filename, O_RDWR);
#endif
char intname[IFNAMSIZ];
strcpy(intname,netif);
fd=tun_alloc(intname);
if (fd < 0) {
BX_PANIC (("open failed on %s: %s", netif, strerror (errno)));
return;
}
/* set O_ASYNC flag so that we can poll with read() */
if ((flags = fcntl( fd, F_GETFL)) < 0) {
BX_PANIC (("getflags on tun device: %s", strerror (errno)));
}
flags |= O_NONBLOCK;
if (fcntl( fd, F_SETFL, flags ) < 0) {
BX_PANIC (("set tun device flags: %s", strerror (errno)));
}
BX_INFO (("eth_tuntap: opened %s device", netif));
/* Execute the configuration script */
char *scriptname=bx_options.ne2k.Oscript->getptr();
if((scriptname != NULL)
&&(strcmp(scriptname, "") != 0)
&&(strcmp(scriptname, "none") != 0)) {
if (execute_script(scriptname, intname) < 0)
BX_ERROR (("execute script '%s' on %s failed", scriptname, intname));
}
// Start the rx poll
this->rx_timer_index =
bx_pc_system.register_timer(this, this->rx_timer_handler, 1000,
1, 1); // continuous, active
this->rxh = rxh;
this->rxarg = rxarg;
#if BX_ETH_TUNTAP_LOGGING
// eventually Bryce wants txlog to dump in pcap format so that
// tcpdump -r FILE can read it and interpret packets.
txlog = fopen ("ne2k-tx.log", "wb");
if (!txlog) BX_PANIC (("open ne2k-tx.log failed"));
txlog_txt = fopen ("ne2k-txdump.txt", "wb");
if (!txlog_txt) BX_PANIC (("open ne2k-txdump.txt failed"));
fprintf (txlog_txt, "tuntap packetmover readable log file\n");
fprintf (txlog_txt, "net IF = %s\n", netif);
fprintf (txlog_txt, "MAC address = ");
for (int i=0; i<6; i++)
fprintf (txlog_txt, "%02x%s", 0xff & macaddr[i], i<5?":" : "");
fprintf (txlog_txt, "\n--\n");
fflush (txlog_txt);
rxlog = fopen ("ne2k-rx.log", "wb");
if (!rxlog) BX_PANIC (("open ne2k-rx.log failed"));
rxlog_txt = fopen ("ne2k-rxdump.txt", "wb");
if (!rxlog_txt) BX_PANIC (("open ne2k-rxdump.txt failed"));
fprintf (rxlog_txt, "tuntap packetmover readable log file\n");
fprintf (rxlog_txt, "net IF = %s\n", netif);
fprintf (rxlog_txt, "MAC address = ");
for (int i=0; i<6; i++)
fprintf (rxlog_txt, "%02x%s", 0xff & macaddr[i], i<5?":" : "");
fprintf (rxlog_txt, "\n--\n");
fflush (rxlog_txt);
#endif
}
void
bx_tuntap_pktmover_c::sendpkt(void *buf, unsigned io_len)
{
#ifdef NEVERDEF
Bit8u txbuf[BX_PACKET_BUFSIZ];
txbuf[0] = 0;
txbuf[1] = 0;
memcpy (txbuf+2, buf, io_len);
unsigned int size = write (fd, txbuf, io_len+2);
if (size != io_len+2) {
BX_PANIC (("write on tuntap device: %s", strerror (errno)));
} else {
BX_INFO (("wrote %d bytes + 2 byte pad on tuntap", io_len));
}
#endif
unsigned int size = write (fd, buf, io_len);
if (size != io_len) {
BX_PANIC (("write on tuntap device: %s", strerror (errno)));
} else {
BX_INFO (("wrote %d bytes on tuntap", io_len));
}
#if BX_ETH_TUNTAP_LOGGING
BX_DEBUG (("sendpkt length %u", io_len));
// dump raw bytes to a file, eventually dump in pcap format so that
// tcpdump -r FILE can interpret them for us.
int n = fwrite (buf, io_len, 1, txlog);
if (n != 1) BX_ERROR (("fwrite to txlog failed", io_len));
// dump packet in hex into an ascii log file
fprintf (txlog_txt, "NE2K transmitting a packet, length %u\n", io_len);
Bit8u *charbuf = (Bit8u *)buf;
for (n=0; n<io_len; n++) {
if (((n % 16) == 0) && n>0)
fprintf (txlog_txt, "\n");
fprintf (txlog_txt, "%02x ", charbuf[n]);
}
fprintf (txlog_txt, "\n--\n");
// flush log so that we see the packets as they arrive w/o buffering
fflush (txlog);
fflush (txlog_txt);
#endif
}
void bx_tuntap_pktmover_c::rx_timer_handler (void *this_ptr)
{
bx_tuntap_pktmover_c *class_ptr = (bx_tuntap_pktmover_c *) this_ptr;
class_ptr->rx_timer();
}
void bx_tuntap_pktmover_c::rx_timer ()
{
int nbytes;
Bit8u buf[BX_PACKET_BUFSIZ];
Bit8u *rxbuf;
if (fd<0) return;
nbytes = read (fd, buf, sizeof(buf));
#ifdef NEVERDEF
// hack: discard first two bytes
rxbuf = buf+2;
nbytes-=2;
#else
rxbuf=buf;
#endif
// hack: TUN/TAP device likes to create an ethernet header which has
// the same source and destination address FE:FD:00:00:00:00.
// Change the dest address to FE:FD:00:00:00:01.
rxbuf[5] = 1;
if (nbytes>0)
BX_INFO (("tuntap read returned %d bytes", nbytes));
if (nbytes<0) {
if (errno != EAGAIN)
BX_ERROR (("tuntap read error: %s", strerror(errno)));
return;
}
#if BX_ETH_TUNTAP_LOGGING
if (nbytes > 0) {
BX_DEBUG (("receive packet length %u", nbytes));
// dump raw bytes to a file, eventually dump in pcap format so that
// tcpdump -r FILE can interpret them for us.
int n = fwrite (rxbuf, nbytes, 1, rxlog);
if (n != 1) BX_ERROR (("fwrite to rxlog failed", nbytes));
// dump packet in hex into an ascii log file
fprintf (rxlog_txt, "NE2K received a packet, length %u\n", nbytes);
for (n=0; n<nbytes; n++) {
if (((n % 16) == 0) && n>0)
fprintf (rxlog_txt, "\n");
fprintf (rxlog_txt, "%02x ", rxbuf[n]);
}
fprintf (rxlog_txt, "\n--\n");
// flush log so that we see the packets as they arrive w/o buffering
fflush (rxlog);
fflush (rxlog_txt);
}
#endif
BX_DEBUG(("eth_tuntap: got packet: %d bytes, dst=%x:%x:%x:%x:%x:%x, src=%x:%x:%x:%x:%x:%x\n", nbytes, rxbuf[0], rxbuf[1], rxbuf[2], rxbuf[3], rxbuf[4], rxbuf[5], rxbuf[6], rxbuf[7], rxbuf[8], rxbuf[9], rxbuf[10], rxbuf[11]));
if (nbytes < 60) {
BX_INFO (("packet too short (%d), padding to 60", nbytes));
nbytes = 60;
}
(*rxh)(rxarg, rxbuf, nbytes);
}
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 )
strncpy(ifr.ifr_name, dev, IFNAMSIZ);
if( (err = ioctl(fd, TUNSETIFF, (void *) &ifr)) < 0 ){
close(fd);
return err;
}
//strcpy(dev, ifr.ifr_name);
ioctl( fd, TUNSETNOCSUM, 1 );
return fd;
}
int execute_script( char* scriptname, char* arg1 )
{
int pid,status;
if (!(pid=fork())) {
char filename[BX_PATHNAME_LEN];
if ( scriptname[0]=='/' ) {
strcpy (filename, scriptname);
}
else {
getcwd (filename, BX_PATHNAME_LEN);
strcat (filename, "/");
strcat (filename, scriptname);
}
// execute the script
BX_INFO(("Executing script '%s %s'",filename,arg1));
execle(filename, scriptname, arg1, NULL, NULL);
// if we get here there has been a problem
exit(-1);
}
wait (&status);
if (!WIFEXITED(status)) {
return -1;
}
return WEXITSTATUS(status);
}