| /* |
| * Copyright (c) 2001, 2002 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 <string.h> |
| #include <unistd.h> |
| #include <sys/types.h> |
| #include <sys/uio.h> |
| #include <sys/socket.h> |
| |
| |
| #include "lwip/debug.h" |
| |
| #include "lwip/opt.h" |
| #include "lwip/def.h" |
| #include "lwip/ip.h" |
| #include "lwip/mem.h" |
| #include "lwip/netif.h" |
| #include "lwip/pbuf.h" |
| #include "lwip/sys.h" |
| |
| |
| #define IFNAME0 't' |
| #define IFNAME1 'n' |
| |
| struct tunif { |
| /* Add whatever per-interface state that is needed here. */ |
| int fd; |
| }; |
| |
| /* Forward declarations. */ |
| static void tunif_input(struct netif *netif); |
| static err_t tunif_output(struct netif *netif, struct pbuf *p, |
| struct ip_addr *ipaddr); |
| |
| static void tunif_thread(void *data); |
| |
| /*-----------------------------------------------------------------------------------*/ |
| static void |
| low_level_init(struct netif *netif) |
| { |
| struct tunif *tunif; |
| char buf[100]; |
| |
| tunif = netif->state; |
| |
| /* Obtain MAC address from network interface. */ |
| |
| /* Do whatever else is needed to initialize interface. */ |
| |
| tunif->fd = open("/dev/tun0", O_RDWR); |
| DEBUGF(TUNIF_DEBUG, ("tunif_init: fd %d\n", tunif->fd)); |
| if(tunif->fd == -1) { |
| perror("tunif_init"); |
| exit(1); |
| } |
| snprintf(buf, sizeof(buf), "ifconfig tun0 inet %d.%d.%d.%d %d.%d.%d.%d", |
| ip4_addr1(&(netif->gw)), |
| ip4_addr2(&(netif->gw)), |
| ip4_addr3(&(netif->gw)), |
| ip4_addr4(&(netif->gw)), |
| ip4_addr1(&(netif->ip_addr)), |
| ip4_addr2(&(netif->ip_addr)), |
| ip4_addr3(&(netif->ip_addr)), |
| ip4_addr4(&(netif->ip_addr))); |
| |
| DEBUGF(TUNIF_DEBUG, ("tunif_init: system(\"%s\");\n", buf)); |
| system(buf); |
| sys_thread_new(tunif_thread, netif); |
| |
| } |
| /*-----------------------------------------------------------------------------------*/ |
| /* |
| * 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 tunif *tunif, struct pbuf *p) |
| { |
| struct pbuf *q; |
| char buf[1500]; |
| char *bufptr; |
| |
| /* initiate transfer(); */ |
| |
| if(((double)rand()/(double)RAND_MAX) < 0.4) { |
| printf("drop\n"); |
| return ERR_OK; |
| } |
| |
| |
| bufptr = &buf[0]; |
| |
| for(q = p; q != NULL; q = q->next) { |
| /* Send the data from the pbuf to the interface, one pbuf at a |
| time. The size of the data in each pbuf is kept in the ->len |
| variable. */ |
| /* send data from(q->payload, q->len); */ |
| bcopy(q->payload, bufptr, q->len); |
| bufptr += q->len; |
| } |
| |
| /* signal that packet should be sent(); */ |
| if(write(tunif->fd, buf, p->tot_len) == -1) { |
| perror("tunif: write"); |
| } |
| 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 tunif *tunif) |
| { |
| struct pbuf *p, *q; |
| u16_t len; |
| char buf[1500]; |
| char *bufptr; |
| |
| /* Obtain the size of the packet and put it into the "len" |
| variable. */ |
| len = read(tunif->fd, buf, sizeof(buf)); |
| |
| /* if(((double)rand()/(double)RAND_MAX) < 0.1) { |
| printf("drop\n"); |
| return NULL; |
| }*/ |
| |
| |
| /* We allocate a pbuf chain of pbufs from the pool. */ |
| p = pbuf_alloc(PBUF_LINK, len, PBUF_POOL); |
| |
| if(p != NULL) { |
| /* We iterate over the pbuf chain until we have read the entire |
| packet into the pbuf. */ |
| bufptr = &buf[0]; |
| for(q = p; q != NULL; q = q->next) { |
| /* Read enough bytes to fill this pbuf in the chain. The |
| avaliable data in the pbuf is given by the q->len |
| variable. */ |
| /* read data into(q->payload, q->len); */ |
| bcopy(bufptr, q->payload, q->len); |
| bufptr += q->len; |
| } |
| /* acknowledge that packet has been read(); */ |
| } else { |
| /* drop packet(); */ |
| } |
| |
| return p; |
| } |
| /*-----------------------------------------------------------------------------------*/ |
| static void |
| tunif_thread(void *arg) |
| { |
| struct netif *netif; |
| struct tunif *tunif; |
| fd_set fdset; |
| int ret; |
| |
| netif = arg; |
| tunif = netif->state; |
| |
| while(1) { |
| FD_ZERO(&fdset); |
| FD_SET(tunif->fd, &fdset); |
| |
| /* Wait for a packet to arrive. */ |
| ret = select(tunif->fd + 1, &fdset, NULL, NULL, NULL); |
| |
| if(ret == 1) { |
| /* Handle incoming packet. */ |
| tunif_input(netif); |
| } else if(ret == -1) { |
| perror("tunif_thread: select"); |
| } |
| } |
| } |
| /*-----------------------------------------------------------------------------------*/ |
| /* |
| * tunif_output(): |
| * |
| * This function is called by the TCP/IP stack when an IP packet |
| * should be sent. It calls the function called low_level_output() to |
| * do the actuall transmission of the packet. |
| * |
| */ |
| /*-----------------------------------------------------------------------------------*/ |
| static err_t |
| tunif_output(struct netif *netif, struct pbuf *p, |
| struct ip_addr *ipaddr) |
| { |
| struct tunif *tunif; |
| |
| tunif = netif->state; |
| |
| return low_level_output(tunif, p); |
| |
| } |
| /*-----------------------------------------------------------------------------------*/ |
| /* |
| * tunif_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 |
| tunif_input(struct netif *netif) |
| { |
| struct tunif *tunif; |
| struct pbuf *p; |
| |
| |
| tunif = netif->state; |
| |
| p = low_level_input(tunif); |
| |
| if(p == NULL) { |
| DEBUGF(TUNIF_DEBUG, ("tunif_input: low_level_input returned NULL\n")); |
| return; |
| } |
| |
| if(ip_lookup(p->payload, netif)) { |
| netif->input(p, netif); |
| } |
| } |
| /*-----------------------------------------------------------------------------------*/ |
| /* |
| * tunif_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. |
| * |
| */ |
| /*-----------------------------------------------------------------------------------*/ |
| void |
| tunif_init(struct netif *netif) |
| { |
| struct tunif *tunif; |
| |
| tunif = mem_malloc(sizeof(struct tunif)); |
| netif->state = tunif; |
| netif->name[0] = IFNAME0; |
| netif->name[1] = IFNAME1; |
| netif->output = tunif_output; |
| |
| |
| low_level_init(netif); |
| } |
| /*-----------------------------------------------------------------------------------*/ |