diff options
Diffstat (limited to 'contrib/ports/unix/port/netif/tapif.c')
| -rw-r--r-- | contrib/ports/unix/port/netif/tapif.c | 432 |
1 files changed, 432 insertions, 0 deletions
diff --git a/contrib/ports/unix/port/netif/tapif.c b/contrib/ports/unix/port/netif/tapif.c new file mode 100644 index 00000000000..cff078382bc --- /dev/null +++ b/contrib/ports/unix/port/netif/tapif.c @@ -0,0 +1,432 @@ +/* + * Copyright (c) 2001-2003 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. 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 lwIP TCP/IP stack. + * + * Author: Adam Dunkels <adam@sics.se> + * + */ + +#include <fcntl.h> +#include <stdlib.h> +#include <stdio.h> +#include <unistd.h> +#include <string.h> +#include <sys/ioctl.h> +#include <sys/socket.h> +#include <sys/types.h> +#include <sys/time.h> +#include <sys/uio.h> +#include <sys/socket.h> + +#include "lwip/opt.h" + +#include "lwip/debug.h" +#include "lwip/def.h" +#include "lwip/ip.h" +#include "lwip/mem.h" +#include "lwip/stats.h" +#include "lwip/snmp.h" +#include "lwip/pbuf.h" +#include "lwip/sys.h" +#include "lwip/timeouts.h" +#include "netif/etharp.h" +#include "lwip/ethip6.h" + +#include "netif/tapif.h" + +#define IFCONFIG_BIN "/sbin/ifconfig " + +#if defined(LWIP_UNIX_LINUX) +#include <sys/ioctl.h> +#include <linux/if.h> +#include <linux/if_tun.h> +/* + * Creating a tap interface requires special privileges. If the interfaces + * is created in advance with `tunctl -u <user>` it can be opened as a regular + * user. The network must already be configured. If DEVTAP_IF is defined it + * will be opened instead of creating a new tap device. + * + * You can also use PRECONFIGURED_TAPIF environment variable to do so. + */ +#ifndef DEVTAP_DEFAULT_IF +#define DEVTAP_DEFAULT_IF "tap0" +#endif +#ifndef DEVTAP +#define DEVTAP "/dev/net/tun" +#endif +#define NETMASK_ARGS "netmask %d.%d.%d.%d" +#define IFCONFIG_ARGS "tap0 inet %d.%d.%d.%d " NETMASK_ARGS +#elif defined(LWIP_UNIX_OPENBSD) +#define DEVTAP "/dev/tun0" +#define NETMASK_ARGS "netmask %d.%d.%d.%d" +#define IFCONFIG_ARGS "tun0 inet %d.%d.%d.%d " NETMASK_ARGS " link0" +#else /* others */ +#define DEVTAP "/dev/tap0" +#define NETMASK_ARGS "netmask %d.%d.%d.%d" +#define IFCONFIG_ARGS "tap0 inet %d.%d.%d.%d " NETMASK_ARGS +#endif + +/* Define those to better describe your network interface. */ +#define IFNAME0 't' +#define IFNAME1 'p' + +#ifndef TAPIF_DEBUG +#define TAPIF_DEBUG LWIP_DBG_OFF +#endif + +struct tapif { + /* Add whatever per-interface state that is needed here. */ + int fd; +}; + +/* Forward declarations. */ +static void tapif_input(struct netif *netif); +#if !NO_SYS +static void tapif_thread(void *arg); +#endif /* !NO_SYS */ + +/*-----------------------------------------------------------------------------------*/ +static void +low_level_init(struct netif *netif) +{ + struct tapif *tapif; +#if LWIP_IPV4 + int ret; + char buf[1024]; +#endif /* LWIP_IPV4 */ + char *preconfigured_tapif = getenv("PRECONFIGURED_TAPIF"); + + tapif = (struct tapif *)netif->state; + + /* Obtain MAC address from network interface. */ + + /* (We just fake an address...) */ + netif->hwaddr[0] = 0x02; + netif->hwaddr[1] = 0x12; + netif->hwaddr[2] = 0x34; + netif->hwaddr[3] = 0x56; + netif->hwaddr[4] = 0x78; + netif->hwaddr[5] = 0xab; + netif->hwaddr_len = 6; + + /* device capabilities */ + netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_IGMP; + + tapif->fd = open(DEVTAP, O_RDWR); + LWIP_DEBUGF(TAPIF_DEBUG, ("tapif_init: fd %d\n", tapif->fd)); + if (tapif->fd == -1) { +#ifdef LWIP_UNIX_LINUX + perror("tapif_init: try running \"modprobe tun\" or rebuilding your kernel with CONFIG_TUN; cannot open "DEVTAP); +#else /* LWIP_UNIX_LINUX */ + perror("tapif_init: cannot open "DEVTAP); +#endif /* LWIP_UNIX_LINUX */ + exit(1); + } + +#ifdef LWIP_UNIX_LINUX + { + struct ifreq ifr; + memset(&ifr, 0, sizeof(ifr)); + + if (preconfigured_tapif) { + strncpy(ifr.ifr_name, preconfigured_tapif, sizeof(ifr.ifr_name) - 1); + } else { + strncpy(ifr.ifr_name, DEVTAP_DEFAULT_IF, sizeof(ifr.ifr_name) - 1); + } + ifr.ifr_name[sizeof(ifr.ifr_name)-1] = 0; /* ensure \0 termination */ + + ifr.ifr_flags = IFF_TAP|IFF_NO_PI; + if (ioctl(tapif->fd, TUNSETIFF, (void *) &ifr) < 0) { + perror("tapif_init: "DEVTAP" ioctl TUNSETIFF"); + exit(1); + } + } +#endif /* LWIP_UNIX_LINUX */ + + netif_set_link_up(netif); + + if (preconfigured_tapif == NULL) { +#if LWIP_IPV4 + snprintf(buf, 1024, IFCONFIG_BIN IFCONFIG_ARGS, + ip4_addr1(netif_ip4_gw(netif)), + ip4_addr2(netif_ip4_gw(netif)), + ip4_addr3(netif_ip4_gw(netif)), + ip4_addr4(netif_ip4_gw(netif)) +#ifdef NETMASK_ARGS + , + ip4_addr1(netif_ip4_netmask(netif)), + ip4_addr2(netif_ip4_netmask(netif)), + ip4_addr3(netif_ip4_netmask(netif)), + ip4_addr4(netif_ip4_netmask(netif)) +#endif /* NETMASK_ARGS */ + ); + + LWIP_DEBUGF(TAPIF_DEBUG, ("tapif_init: system(\"%s\");\n", buf)); + ret = system(buf); + if (ret < 0) { + perror("ifconfig failed"); + exit(1); + } + if (ret != 0) { + printf("ifconfig returned %d\n", ret); + } +#else /* LWIP_IPV4 */ + perror("todo: support IPv6 support for non-preconfigured tapif"); + exit(1); +#endif /* LWIP_IPV4 */ + } + +#if !NO_SYS + sys_thread_new("tapif_thread", tapif_thread, netif, DEFAULT_THREAD_STACKSIZE, DEFAULT_THREAD_PRIO); +#endif /* !NO_SYS */ +} +/*-----------------------------------------------------------------------------------*/ +/* + * low_level_output(): + * + * Should do the actual transmission of the packet. The packet is + * contained in the pbuf that is passed to the function. This pbuf + * might be chained. + * + */ +/*-----------------------------------------------------------------------------------*/ + +static err_t +low_level_output(struct netif *netif, struct pbuf *p) +{ + struct tapif *tapif = (struct tapif *)netif->state; + char buf[1518]; /* max packet size including VLAN excluding CRC */ + ssize_t written; + +#if 0 + if (((double)rand()/(double)RAND_MAX) < 0.2) { + printf("drop output\n"); + return ERR_OK; /* ERR_OK because we simulate packet loss on cable */ + } +#endif + + if (p->tot_len > sizeof(buf)) { + MIB2_STATS_NETIF_INC(netif, ifoutdiscards); + perror("tapif: packet too large"); + return ERR_IF; + } + + /* initiate transfer(); */ + pbuf_copy_partial(p, buf, p->tot_len, 0); + + /* signal that packet should be sent(); */ + written = write(tapif->fd, buf, p->tot_len); + if (written < p->tot_len) { + MIB2_STATS_NETIF_INC(netif, ifoutdiscards); + perror("tapif: write"); + return ERR_IF; + } else { + MIB2_STATS_NETIF_ADD(netif, ifoutoctets, (u32_t)written); + return ERR_OK; + } +} +/*-----------------------------------------------------------------------------------*/ +/* + * low_level_input(): + * + * Should allocate a pbuf and transfer the bytes of the incoming + * packet from the interface into the pbuf. + * + */ +/*-----------------------------------------------------------------------------------*/ +static struct pbuf * +low_level_input(struct netif *netif) +{ + struct pbuf *p; + u16_t len; + ssize_t readlen; + char buf[1518]; /* max packet size including VLAN excluding CRC */ + struct tapif *tapif = (struct tapif *)netif->state; + + /* Obtain the size of the packet and put it into the "len" + variable. */ + readlen = read(tapif->fd, buf, sizeof(buf)); + if (readlen < 0) { + perror("read returned -1"); + exit(1); + } + len = (u16_t)readlen; + + MIB2_STATS_NETIF_ADD(netif, ifinoctets, len); + +#if 0 + if (((double)rand()/(double)RAND_MAX) < 0.2) { + printf("drop\n"); + return NULL; + } +#endif + + /* We allocate a pbuf chain of pbufs from the pool. */ + p = pbuf_alloc(PBUF_RAW, len, PBUF_POOL); + if (p != NULL) { + pbuf_take(p, buf, len); + /* acknowledge that packet has been read(); */ + } else { + /* drop packet(); */ + MIB2_STATS_NETIF_INC(netif, ifindiscards); + LWIP_DEBUGF(NETIF_DEBUG, ("tapif_input: could not allocate pbuf\n")); + } + + return p; +} + +/*-----------------------------------------------------------------------------------*/ +/* + * tapif_input(): + * + * This function should be called when a packet is ready to be read + * from the interface. It uses the function low_level_input() that + * should handle the actual reception of bytes from the network + * interface. + * + */ +/*-----------------------------------------------------------------------------------*/ +static void +tapif_input(struct netif *netif) +{ + struct pbuf *p = low_level_input(netif); + + if (p == NULL) { +#if LINK_STATS + LINK_STATS_INC(link.recv); +#endif /* LINK_STATS */ + LWIP_DEBUGF(TAPIF_DEBUG, ("tapif_input: low_level_input returned NULL\n")); + return; + } + + if (netif->input(p, netif) != ERR_OK) { + LWIP_DEBUGF(NETIF_DEBUG, ("tapif_input: netif input error\n")); + pbuf_free(p); + } +} +/*-----------------------------------------------------------------------------------*/ +/* + * tapif_init(): + * + * Should be called at the beginning of the program to set up the + * network interface. It calls the function low_level_init() to do the + * actual setup of the hardware. + * + */ +/*-----------------------------------------------------------------------------------*/ +err_t +tapif_init(struct netif *netif) +{ + struct tapif *tapif = (struct tapif *)mem_malloc(sizeof(struct tapif)); + + if (tapif == NULL) { + LWIP_DEBUGF(NETIF_DEBUG, ("tapif_init: out of memory for tapif\n")); + return ERR_MEM; + } + netif->state = tapif; + MIB2_INIT_NETIF(netif, snmp_ifType_other, 100000000); + + netif->name[0] = IFNAME0; + netif->name[1] = IFNAME1; +#if LWIP_IPV4 + netif->output = etharp_output; +#endif /* LWIP_IPV4 */ +#if LWIP_IPV6 + netif->output_ip6 = ethip6_output; +#endif /* LWIP_IPV6 */ + netif->linkoutput = low_level_output; + netif->mtu = 1500; + + low_level_init(netif); + + return ERR_OK; +} + + +/*-----------------------------------------------------------------------------------*/ +void +tapif_poll(struct netif *netif) +{ + tapif_input(netif); +} + +#if NO_SYS + +int +tapif_select(struct netif *netif) +{ + fd_set fdset; + int ret; + struct timeval tv; + struct tapif *tapif; + u32_t msecs = sys_timeouts_sleeptime(); + + tapif = (struct tapif *)netif->state; + + tv.tv_sec = msecs / 1000; + tv.tv_usec = (msecs % 1000) * 1000; + + FD_ZERO(&fdset); + FD_SET(tapif->fd, &fdset); + + ret = select(tapif->fd + 1, &fdset, NULL, NULL, &tv); + if (ret > 0) { + tapif_input(netif); + } + return ret; +} + +#else /* NO_SYS */ + +static void +tapif_thread(void *arg) +{ + struct netif *netif; + struct tapif *tapif; + fd_set fdset; + int ret; + + netif = (struct netif *)arg; + tapif = (struct tapif *)netif->state; + + while(1) { + FD_ZERO(&fdset); + FD_SET(tapif->fd, &fdset); + + /* Wait for a packet to arrive. */ + ret = select(tapif->fd + 1, &fdset, NULL, NULL, NULL); + + if(ret == 1) { + /* Handle incoming packet. */ + tapif_input(netif); + } else if(ret == -1) { + perror("tapif_thread: select"); + } + } +} + +#endif /* NO_SYS */ |