/**************************************************************************** * arch/sim/src/up_tapdev.c * * Copyright (C) 2007-2009, 2011, 2016 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Based on code from uIP which also has a BSD-like license: * * Copyright (c) 2001, Adam Dunkels. * 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 NuttX 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 COPYRIGHT HOLDERS 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 * COPYRIGHT OWNER 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. * ****************************************************************************/ #ifndef __CYGWIN__ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include #include #ifdef CONFIG_SIM_NET_HOST_ROUTE # include #endif #include #include #include #include #include /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ //#define TAPDEV_DEBUG 1 #define DEVTAP "/dev/net/tun" /* Syslog priority (must match definitions in nuttx/include/syslog.h) */ #define LOG_INFO 1 /* Informational message */ #define LOG_ERR 4 /* Error conditions */ /**************************************************************************** * Private Types ****************************************************************************/ /* Warning: This is very much Linux version specific! */ struct sel_arg_struct { unsigned long n; fd_set *inp; fd_set *outp; fd_set *exp; struct timeval *tvp; }; /**************************************************************************** * NuttX Domain Public Function Prototypes ****************************************************************************/ int syslog(int priority, const char *format, ...); int netdriver_setmacaddr(unsigned char *macaddr); /**************************************************************************** * Private Data ****************************************************************************/ #ifdef TAPDEV_DEBUG static int gdrop = 0; #endif static int gtapdevfd; static char gdevname[IFNAMSIZ]; #ifdef CONFIG_SIM_NET_HOST_ROUTE static struct rtentry ghostroute; #endif /**************************************************************************** * Private Functions ****************************************************************************/ #ifdef TAPDEV_DEBUG static inline void dump_ethhdr(const char *msg, unsigned char *buf, int buflen) { syslog(LOG_INFO, "TAPDEV: %s %d bytes\n", msg, buflen); syslog(LOG_INFO, " %02x:%02x:%02x:%02x:%02x:%02x %02x:%02x:%02x:%02x:%02x:%02x %02x%02x\n", buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6], buf[7], buf[8], buf[9], buf[10], buf[11], #ifdef CONFIG_ENDIAN_BIG buf[13], buf[12]); #else buf[12], buf[13]); #endif } #else # define dump_ethhdr(m,b,l) #endif static int up_setmacaddr(void) { unsigned char mac[7]; int ret = -1; /* Assign a random locally-created MAC address. * * This previously took the address from the TAP interface; that was * incorrect, as that hardware address belongs to the host system. Packets * destined for the application aren't guaranteed to reach it if you do * that, as the host may handle them at its discretion. * * With a unique MAC address, we get ALL the packets. * * TODO: The generated MAC address should be checked to see if it * conflicts with something else on the network. */ srand(time(NULL)); mac[0] = 0x42; mac[1] = rand() % 256; mac[2] = rand() % 256; mac[3] = rand() % 256; mac[4] = rand() % 256; mac[5] = rand() % 256; mac[6] = 0; ret = netdriver_setmacaddr(mac); return ret; } /**************************************************************************** * Public Functions ****************************************************************************/ void tapdev_init(void) { struct ifreq ifr; int ret; #ifdef CONFIG_SIM_NET_BRIDGE int sockfd; #endif /* Open the tap device */ gtapdevfd = open(DEVTAP, O_RDWR, 0644); if (gtapdevfd < 0) { syslog(LOG_ERR, "TAPDEV: open failed: %d\n", -gtapdevfd); return; } /* Configure the tap device */ memset(&ifr, 0, sizeof(ifr)); ifr.ifr_flags = IFF_TAP | IFF_NO_PI; ret = ioctl(gtapdevfd, TUNSETIFF, (unsigned long) &ifr); if (ret < 0) { syslog(LOG_ERR, "TAPDEV: ioctl failed: %d\n", -ret); return; } /* Save the tap device name */ strncpy(gdevname, ifr.ifr_name, IFNAMSIZ); #ifdef CONFIG_SIM_NET_BRIDGE /* Get a socket with which to manipulate the tap device; the remaining * ioctl calls unfortunately won't work on the tap device fd. */ sockfd = socket(AF_INET, SOCK_DGRAM, 0); if (sockfd < 0) { syslog(LOG_ERR, "TAPDEV: Can't open socket: %d\n", -sockfd); return; } /* Assign the tap device to a bridge */ memset(&ifr, 0, sizeof(ifr)); strncpy(ifr.ifr_name, CONFIG_SIM_NET_BRIDGE_DEVICE, IFNAMSIZ); ifr.ifr_ifindex = if_nametoindex(gdevname); ret = ioctl(sockfd, SIOCBRADDIF, &ifr); if (ret < 0) { syslog(LOG_ERR, "TAPDEV: ioctl failed (can't add interface %s to bridge %s): %d\n", gdevname, CONFIG_SIM_NET_BRIDGE_DEVICE, -ret); } close(sockfd); #endif /* Set the MAC address */ up_setmacaddr(); } unsigned int tapdev_read(unsigned char *buf, unsigned int buflen) { fd_set fdset; struct timeval tv; int ret; /* We can't do anything if we failed to open the tap device */ if (gtapdevfd < 0) { return 0; } /* Wait for data on the tap device (or a timeout) */ tv.tv_sec = 0; tv.tv_usec = 1000; FD_ZERO(&fdset); FD_SET(gtapdevfd, &fdset); ret = select(gtapdevfd + 1, &fdset, NULL, NULL, &tv); if (ret == 0) { return 0; } ret = read(gtapdevfd, buf, buflen); if (ret < 0) { syslog(LOG_ERR, "TAPDEV: read failed: %d\n", -ret); return 0; } dump_ethhdr("read", buf, ret); return ret; } void tapdev_send(unsigned char *buf, unsigned int buflen) { int ret; #ifdef TAPDEV_DEBUG syslog(LOG_INFO, "tapdev_send: sending %d bytes\n", buflen); gdrop++; if (gdrop % 8 == 7) { syslog(LOG_ERR, "TAPDEV: Dropped a packet!\n"); return; } #endif ret = write(gtapdevfd, buf, buflen); if (ret < 0) { syslog(LOG_ERR, "TAPDEV: write failed: %d", -ret); exit(1); } dump_ethhdr("write", buf, buflen); } void tapdev_ifup(in_addr_t ifaddr) { struct ifreq ifr; int sockfd; int ret; #ifdef CONFIG_SIM_NET_HOST_ROUTE struct sockaddr_in *addr; #endif /* Get a socket with which to manipulate the tap device */ sockfd = socket(AF_INET, SOCK_DGRAM, 0); if (sockfd < 0) { syslog(LOG_ERR, "TAPDEV: Can't open socket: %d\n", -sockfd); return; } /* Bring the TAP interface up */ strncpy(ifr.ifr_name, gdevname, IFNAMSIZ); ret = ioctl(sockfd, SIOCGIFFLAGS, (unsigned long)&ifr); if (ret < 0) { syslog(LOG_ERR, "TAPDEV: ioctl failed (can't get interface flags): %d\n", -ret); close(sockfd); return; } ifr.ifr_flags |= IFF_UP; ret = ioctl(sockfd, SIOCSIFFLAGS, (unsigned long)&ifr); if (ret < 0) { syslog(LOG_ERR, "TAPDEV: ioctl failed (can't set interface flags): %d\n", -ret); close(sockfd); return; } #ifdef CONFIG_SIM_NET_HOST_ROUTE /* Add host route */ memset(&ghostroute, 0, sizeof(ghostroute)); addr = (struct sockaddr_in *)&ghostroute.rt_dst; addr->sin_family = AF_INET; addr->sin_addr.s_addr = ifaddr; ghostroute.rt_dev = gdevname; ghostroute.rt_flags = RTF_UP | RTF_HOST; ghostroute.rt_metric = 0; ret = ioctl(sockfd, SIOCADDRT, (unsigned long)&ghostroute); if (ret < 0) { syslog(LOG_ERR, "TAPDEV: ioctl failed (can't add host route): %d\n", -ret); close(sockfd); return; } #endif close(sockfd); } void tapdev_ifdown(void) { #ifdef CONFIG_SIM_NET_HOST_ROUTE int sockfd; int ret; if (((struct sockaddr_in *)&ghostroute.rt_dst)->sin_addr.s_addr != 0) { /* Get a socket with which to manipulate the tap device */ sockfd = socket(AF_INET, SOCK_DGRAM, 0); if (sockfd < 0) { syslog(LOG_ERR, "TAPDEV: Can't open socket: %d\n", -sockfd); return; } ret = ioctl(sockfd, SIOCDELRT, (unsigned long)&ghostroute); if (ret < 0) { syslog(LOG_ERR, "TAPDEV: ioctl failed (can't delete host route): %d\n", -ret); } close(sockfd); } #endif } #endif /* !__CYGWIN__ */