///////////////////////////////////////////////////////////////////////// // $Id: eth_tuntap.cc,v 1.9 2003-04-26 14:48:45 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 // // 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. // // Define BX_PLUGGABLE in files that can be compiled into plugins. For // platforms that require a special tag on exported symbols, BX_PLUGGABLE // is used to know when we are exporting symbols and when we are importing. #define BX_PLUGGABLE #include "bochs.h" #if BX_NE2K_SUPPORT #define LOG_THIS bx_devices.pluginNE2kDevice-> #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #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); // // 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; if (strncmp (netif, "tun", 3) != 0) { BX_PANIC (("eth_tuntap: interface name (%s) must be tun", netif)); } #ifdef NEVERDEF char filename[BX_PATHNAME_LEN]; 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, "eth_tuntap"); // 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; n0) 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; n0) 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; } #endif /* if BX_NE2K_SUPPORT */