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dpavlin |
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/* |
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dpavlin |
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* Copyright (C) 2004-2007 Anders Gavare. All rights reserved. |
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dpavlin |
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* |
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* Redistribution and use in source and binary forms, with or without |
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* modification, are permitted provided that the following conditions are met: |
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* |
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* 1. Redistributions of source code must retain the above copyright |
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* notice, this list of conditions and the following disclaimer. |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in the |
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* documentation and/or other materials provided with the distribution. |
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* 3. The name of the author may not be used to endorse or promote products |
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* derived from this software without specific prior written permission. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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* SUCH DAMAGE. |
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* |
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* |
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dpavlin |
34 |
* $Id: net.c,v 1.7 2006/12/30 13:31:02 debug Exp $ |
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dpavlin |
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* |
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* Emulated network. |
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* |
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* (Read the README file in this directory for more details.) |
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* |
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* |
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* NOTE: The 'extra' argument used in many functions in this file is a pointer |
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* to something unique for each NIC (i.e. the NIC itself :-), so that if |
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* multiple NICs are emulated concurrently, they will not get packets that |
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* are meant for some other controller. |
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*/ |
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#include <stdio.h> |
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#include <stdlib.h> |
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#include <string.h> |
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#include <unistd.h> |
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#include <errno.h> |
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#include <sys/types.h> |
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#include <sys/socket.h> |
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#include <netinet/in.h> |
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#include <arpa/inet.h> |
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#include <netdb.h> |
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#include <fcntl.h> |
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#include <signal.h> |
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#include "machine.h" |
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#include "misc.h" |
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#include "net.h" |
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/* #define debug fatal */ |
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61 |
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/* |
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* net_allocate_ethernet_packet_link(): |
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* |
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* This routine allocates an ethernet_packet_link struct, and adds it at |
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* the end of the packet chain. A data buffer is allocated, and the data, |
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* extra, and len fields of the link are set. |
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* |
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* Note: The data buffer is not zeroed. |
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* |
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* Return value is a pointer to the link on success. It doesn't return on |
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* failure. |
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*/ |
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struct ethernet_packet_link *net_allocate_ethernet_packet_link( |
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struct net *net, void *extra, size_t len) |
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{ |
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struct ethernet_packet_link *lp; |
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lp = malloc(sizeof(struct ethernet_packet_link)); |
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if (lp == NULL) |
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goto fail; |
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lp->len = len; |
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lp->extra = extra; |
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lp->data = malloc(len); |
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if (lp->data == NULL) |
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goto fail; |
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lp->next = NULL; |
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/* Add last in the link chain: */ |
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lp->prev = net->last_ethernet_packet; |
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if (lp->prev != NULL) |
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lp->prev->next = lp; |
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else |
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net->first_ethernet_packet = lp; |
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net->last_ethernet_packet = lp; |
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return lp; |
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fail: |
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fprintf(stderr, "net_allocate_ethernet_packet_link(): out of memory\n"); |
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exit(1); |
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} |
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/* |
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* net_arp(): |
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* |
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* Handle an ARP (or RARP) packet, coming from the emulated NIC. |
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* |
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* An ARP packet might look like this: |
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* |
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* ARP header: |
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* ARP hardware addr family: 0001 |
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* ARP protocol addr family: 0800 |
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* ARP addr lengths: 06 04 |
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* ARP request: 0001 |
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* ARP from: 112233445566 01020304 |
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* ARP to: 000000000000 01020301 |
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* |
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* An ARP request with a 'to' IP value of the gateway should cause an |
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* ARP response packet to be created. |
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* |
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* An ARP request with the same from and to IP addresses should be ignored. |
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* (This would be a host testing to see if there is an IP collision.) |
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*/ |
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static void net_arp(struct net *net, void *extra, |
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unsigned char *packet, int len, int reverse) |
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{ |
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int q; |
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int i; |
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/* TODO: This debug dump assumes ethernet->IPv4 translation: */ |
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if (reverse) |
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debug("[ net: RARP: "); |
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else |
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debug("[ net: ARP: "); |
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for (i=0; i<2; i++) |
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debug("%02x", packet[i]); |
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debug(" "); |
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for (i=2; i<4; i++) |
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debug("%02x", packet[i]); |
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debug(" "); |
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debug("%02x", packet[4]); |
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debug(" "); |
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debug("%02x", packet[5]); |
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debug(" req="); |
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debug("%02x", packet[6]); /* Request type */ |
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debug("%02x", packet[7]); |
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debug(" from="); |
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for (i=8; i<18; i++) |
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debug("%02x", packet[i]); |
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debug(" to="); |
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for (i=18; i<28; i++) |
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debug("%02x", packet[i]); |
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debug(" ]\n"); |
158 |
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if (packet[0] == 0x00 && packet[1] == 0x01 && |
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packet[2] == 0x08 && packet[3] == 0x00 && |
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packet[4] == 0x06 && packet[5] == 0x04) { |
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int r = (packet[6] << 8) + packet[7]; |
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struct ethernet_packet_link *lp; |
164 |
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switch (r) { |
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case 1: /* Request */ |
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/* Only create a reply if this was meant for the |
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gateway: */ |
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if (memcmp(packet+24, net->gateway_ipv4_addr, 4) != 0) |
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break; |
171 |
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lp = net_allocate_ethernet_packet_link( |
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net, extra, 60 + 14); |
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/* Copy the old packet first: */ |
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memset(lp->data, 0, 60 + 14); |
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memcpy(lp->data + 14, packet, len); |
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/* Add ethernet ARP header: */ |
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memcpy(lp->data + 0, lp->data + 8 + 14, 6); |
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memcpy(lp->data + 6, net->gateway_ethernet_addr, 6); |
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lp->data[12] = 0x08; lp->data[13] = 0x06; |
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/* Address of the emulated machine: */ |
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memcpy(lp->data + 18 + 14, lp->data + 8 + 14, 10); |
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/* Address of the gateway: */ |
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memcpy(lp->data + 8 + 14, net->gateway_ethernet_addr, |
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6); |
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memcpy(lp->data + 14 + 14, net->gateway_ipv4_addr, 4); |
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/* This is a Reply: */ |
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lp->data[6 + 14] = 0x00; lp->data[7 + 14] = 0x02; |
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break; |
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case 3: /* Reverse Request */ |
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lp = net_allocate_ethernet_packet_link( |
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net, extra, 60 + 14); |
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/* Copy the old packet first: */ |
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memset(lp->data, 0, 60 + 14); |
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memcpy(lp->data + 14, packet, len); |
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/* Add ethernet RARP header: */ |
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memcpy(lp->data + 0, packet + 8, 6); |
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memcpy(lp->data + 6, net->gateway_ethernet_addr, 6); |
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lp->data[12] = 0x80; lp->data[13] = 0x35; |
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/* This is a RARP reply: */ |
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lp->data[6 + 14] = 0x00; lp->data[7 + 14] = 0x04; |
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/* Address of the gateway: */ |
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memcpy(lp->data + 8 + 14, net->gateway_ethernet_addr, |
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6); |
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memcpy(lp->data + 14 + 14, net->gateway_ipv4_addr, 4); |
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217 |
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/* MAC address of emulated machine: */ |
218 |
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memcpy(lp->data + 18 + 14, packet + 8, 6); |
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220 |
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/* |
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* IP address of the emulated machine: Automagically |
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* generated from the MAC address. :-) |
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* |
224 |
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* packet+8 points to the client's mac address, |
225 |
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* for example 10:20:30:00:00:z0, where z is 0..15. |
226 |
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* 10:20:30:00:00:10 results in 10.0.0.1. |
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*/ |
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/* q = (packet[8 + 3]) >> 4; */ |
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/* q = q*15 + ((packet[8 + 4]) >> 4); */ |
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q = (packet[8 + 5]) >> 4; |
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lp->data[24 + 14] = 10; |
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lp->data[25 + 14] = 0; |
233 |
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lp->data[26 + 14] = 0; |
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lp->data[27 + 14] = q; |
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break; |
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case 2: /* Reply */ |
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case 4: /* Reverse Reply */ |
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default: |
239 |
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fatal("[ net: ARP: UNIMPLEMENTED request type " |
240 |
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"0x%04x ]\n", r); |
241 |
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} |
242 |
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} else { |
243 |
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fatal("[ net: ARP: UNIMPLEMENTED arp packet type: "); |
244 |
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for (i=0; i<len; i++) |
245 |
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fatal("%02x", packet[i]); |
246 |
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fatal(" ]\n"); |
247 |
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} |
248 |
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} |
249 |
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250 |
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251 |
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/* |
252 |
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* net_ethernet_rx_avail(): |
253 |
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* |
254 |
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* Return 1 if there is a packet available for this 'extra' pointer, otherwise |
255 |
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* return 0. |
256 |
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* |
257 |
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* Appart from actually checking for incoming packets from the outside world, |
258 |
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* this function basically works like net_ethernet_rx() but it only receives |
259 |
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* a return value telling us whether there is a packet or not, we don't |
260 |
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* actually get the packet. |
261 |
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*/ |
262 |
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int net_ethernet_rx_avail(struct net *net, void *extra) |
263 |
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{ |
264 |
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if (net == NULL) |
265 |
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return 0; |
266 |
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267 |
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/* |
268 |
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* If the network is distributed across multiple emulator processes, |
269 |
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* then receive incoming packets from those processes. |
270 |
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*/ |
271 |
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if (net->local_port != 0) { |
272 |
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struct sockaddr_in si; |
273 |
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socklen_t si_len = sizeof(si); |
274 |
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int res, i, nreceived = 0; |
275 |
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unsigned char buf[60000]; |
276 |
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277 |
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do { |
278 |
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res = recvfrom(net->local_port_socket, buf, |
279 |
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sizeof(buf), 0, (struct sockaddr *)&si, &si_len); |
280 |
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281 |
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if (res != -1) { |
282 |
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nreceived ++; |
283 |
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284 |
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/* fatal("[ incoming DISTRIBUTED packet, %i " |
285 |
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"bytes from %s:%d\n", res, |
286 |
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inet_ntoa(si.sin_addr), |
287 |
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ntohs(si.sin_port)); */ |
288 |
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289 |
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/* Add the packet to all "our" NICs on this |
290 |
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network: */ |
291 |
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for (i=0; i<net->n_nics; i++) { |
292 |
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struct ethernet_packet_link *lp; |
293 |
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lp = net_allocate_ethernet_packet_link( |
294 |
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net, net->nic_extra[i], res); |
295 |
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memcpy(lp->data, buf, res); |
296 |
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} |
297 |
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} |
298 |
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} while (res != -1 && nreceived < 100); |
299 |
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} |
300 |
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301 |
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/* IP protocol specific: */ |
302 |
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net_udp_rx_avail(net, extra); |
303 |
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net_tcp_rx_avail(net, extra); |
304 |
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305 |
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return net_ethernet_rx(net, extra, NULL, NULL); |
306 |
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} |
307 |
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308 |
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309 |
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/* |
310 |
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* net_ethernet_rx(): |
311 |
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* |
312 |
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* Receive an ethernet packet. (This means handing over an already prepared |
313 |
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* packet from this module to a specific ethernet controller device.) |
314 |
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* |
315 |
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* Return value is 1 if there was a packet available. *packetp and *lenp |
316 |
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* will be set to the packet's data pointer and length, respectively, and |
317 |
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* the packet will be removed from the linked list). If there was no packet |
318 |
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* available, 0 is returned. |
319 |
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* |
320 |
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* If packetp is NULL, then the search is aborted as soon as a packet with |
321 |
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* the correct 'extra' field is found, and a 1 is returned, but as packetp |
322 |
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* is NULL we can't return the actual packet. (This is the internal form |
323 |
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* if net_ethernet_rx_avail().) |
324 |
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*/ |
325 |
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int net_ethernet_rx(struct net *net, void *extra, |
326 |
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unsigned char **packetp, int *lenp) |
327 |
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{ |
328 |
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struct ethernet_packet_link *lp, *prev; |
329 |
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330 |
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if (net == NULL) |
331 |
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return 0; |
332 |
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|
333 |
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/* Find the first packet which has the right 'extra' field. */ |
334 |
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|
335 |
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lp = net->first_ethernet_packet; |
336 |
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prev = NULL; |
337 |
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while (lp != NULL) { |
338 |
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if (lp->extra == extra) { |
339 |
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/* We found a packet for this controller! */ |
340 |
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if (packetp == NULL || lenp == NULL) |
341 |
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return 1; |
342 |
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343 |
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/* Let's return it: */ |
344 |
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(*packetp) = lp->data; |
345 |
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(*lenp) = lp->len; |
346 |
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347 |
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/* Remove this link from the linked list: */ |
348 |
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if (prev == NULL) |
349 |
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net->first_ethernet_packet = lp->next; |
350 |
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else |
351 |
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prev->next = lp->next; |
352 |
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353 |
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if (lp->next == NULL) |
354 |
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net->last_ethernet_packet = prev; |
355 |
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else |
356 |
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lp->next->prev = prev; |
357 |
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358 |
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free(lp); |
359 |
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360 |
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/* ... and return successfully: */ |
361 |
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return 1; |
362 |
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} |
363 |
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364 |
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prev = lp; |
365 |
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lp = lp->next; |
366 |
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} |
367 |
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368 |
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/* No packet found. :-( */ |
369 |
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return 0; |
370 |
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} |
371 |
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|
372 |
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|
373 |
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/* |
374 |
|
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* net_ethernet_tx(): |
375 |
|
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* |
376 |
|
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* Transmit an ethernet packet, as seen from the emulated ethernet controller. |
377 |
|
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* If the packet can be handled here, it will not necessarily be transmitted |
378 |
|
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* to the outside world. |
379 |
|
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*/ |
380 |
|
|
void net_ethernet_tx(struct net *net, void *extra, |
381 |
|
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unsigned char *packet, int len) |
382 |
|
|
{ |
383 |
|
|
int i, eth_type, for_the_gateway; |
384 |
|
|
|
385 |
|
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if (net == NULL) |
386 |
|
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return; |
387 |
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|
388 |
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for_the_gateway = !memcmp(packet, net->gateway_ethernet_addr, 6); |
389 |
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|
390 |
|
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/* Drop too small packets: */ |
391 |
|
|
if (len < 20) { |
392 |
|
|
fatal("[ net_ethernet_tx: Warning: dropping tiny packet " |
393 |
|
|
"(%i bytes) ]\n", len); |
394 |
|
|
return; |
395 |
|
|
} |
396 |
|
|
|
397 |
|
|
/* |
398 |
|
|
* Copy this packet to all other NICs on this network (except if |
399 |
|
|
* it is aimed specifically at the gateway's ethernet address): |
400 |
|
|
*/ |
401 |
|
|
if (!for_the_gateway && extra != NULL && net->n_nics > 0) { |
402 |
|
|
for (i=0; i<net->n_nics; i++) |
403 |
|
|
if (extra != net->nic_extra[i]) { |
404 |
|
|
struct ethernet_packet_link *lp; |
405 |
|
|
lp = net_allocate_ethernet_packet_link(net, |
406 |
|
|
net->nic_extra[i], len); |
407 |
|
|
|
408 |
|
|
/* Copy the entire packet: */ |
409 |
|
|
memcpy(lp->data, packet, len); |
410 |
|
|
} |
411 |
|
|
} |
412 |
|
|
|
413 |
|
|
/* |
414 |
|
|
* If this network is distributed across multiple emulator processes, |
415 |
|
|
* then transmit the packet to those other processes. |
416 |
|
|
*/ |
417 |
|
|
if (!for_the_gateway && net->remote_nets != NULL) { |
418 |
|
|
struct remote_net *rnp = net->remote_nets; |
419 |
|
|
while (rnp != NULL) { |
420 |
|
|
send_udp(&rnp->ipv4_addr, rnp->portnr, packet, len); |
421 |
|
|
rnp = rnp->next; |
422 |
|
|
} |
423 |
|
|
} |
424 |
|
|
|
425 |
|
|
|
426 |
|
|
/* |
427 |
|
|
* The code below simulates the behaviour of a "NAT"-style gateway. |
428 |
|
|
* |
429 |
|
|
* Packets that are not destined for the gateway are dropped first: |
430 |
|
|
* (DHCP packets are let through, though.) |
431 |
|
|
*/ |
432 |
|
|
|
433 |
|
|
if (!for_the_gateway && packet[0] != 0xff && packet[0] != 0x00) |
434 |
|
|
return; |
435 |
|
|
|
436 |
|
|
#if 0 |
437 |
|
|
fatal("[ net: ethernet: "); |
438 |
|
|
for (i=0; i<6; i++) fatal("%02x", packet[i]); fatal(" "); |
439 |
|
|
for (i=6; i<12; i++) fatal("%02x", packet[i]); fatal(" "); |
440 |
|
|
for (i=12; i<14; i++) fatal("%02x", packet[i]); fatal(" "); |
441 |
|
|
for (i=14; i<len; i++) fatal("%02x", packet[i]); fatal(" ]\n"); |
442 |
|
|
#endif |
443 |
|
|
|
444 |
|
|
eth_type = (packet[12] << 8) + packet[13]; |
445 |
|
|
|
446 |
|
|
/* IP: */ |
447 |
|
|
if (eth_type == ETHERTYPE_IP) { |
448 |
|
|
/* Routed via the gateway? */ |
449 |
|
|
if (for_the_gateway) { |
450 |
|
|
net_ip(net, extra, packet, len); |
451 |
|
|
return; |
452 |
|
|
} |
453 |
|
|
|
454 |
|
|
/* Broadcast? (DHCP does this.) */ |
455 |
|
|
if (packet[0] == 0xff && packet[1] == 0xff && |
456 |
|
|
packet[2] == 0xff && packet[3] == 0xff && |
457 |
|
|
packet[4] == 0xff && packet[5] == 0xff) { |
458 |
|
|
net_ip_broadcast(net, extra, packet, len); |
459 |
|
|
return; |
460 |
|
|
} |
461 |
|
|
|
462 |
|
|
if (net->n_nics < 2) { |
463 |
|
|
fatal("[ net_ethernet_tx: IP packet not for gateway, " |
464 |
|
|
"and not broadcast: "); |
465 |
|
|
for (i=0; i<14; i++) |
466 |
|
|
fatal("%02x", packet[i]); |
467 |
|
|
fatal(" ]\n"); |
468 |
|
|
} |
469 |
|
|
return; |
470 |
|
|
} |
471 |
|
|
|
472 |
|
|
/* ARP: */ |
473 |
|
|
if (eth_type == ETHERTYPE_ARP) { |
474 |
|
|
if (len != 42 && len != 60) |
475 |
|
|
fatal("[ net_ethernet_tx: WARNING! unusual " |
476 |
|
|
"ARP len (%i) ]\n", len); |
477 |
|
|
net_arp(net, extra, packet + 14, len - 14, 0); |
478 |
|
|
return; |
479 |
|
|
} |
480 |
|
|
|
481 |
|
|
/* RARP: */ |
482 |
|
|
if (eth_type == ETHERTYPE_REVARP) { |
483 |
|
|
net_arp(net, extra, packet + 14, len - 14, 1); |
484 |
|
|
return; |
485 |
|
|
} |
486 |
|
|
|
487 |
|
|
/* Sprite: */ |
488 |
|
|
if (eth_type == ETHERTYPE_SPRITE) { |
489 |
|
|
/* TODO. */ |
490 |
|
|
fatal("[ net: TX: UNIMPLEMENTED Sprite packet ]\n"); |
491 |
|
|
return; |
492 |
|
|
} |
493 |
|
|
|
494 |
|
|
/* IPv6: */ |
495 |
|
|
if (eth_type == ETHERTYPE_IPV6) { |
496 |
|
|
/* TODO. */ |
497 |
|
|
fatal("[ net_ethernet_tx: IPv6 is not implemented yet! ]\n"); |
498 |
|
|
return; |
499 |
|
|
} |
500 |
|
|
|
501 |
|
|
fatal("[ net_ethernet_tx: ethernet packet type 0x%04x not yet " |
502 |
|
|
"implemented ]\n", eth_type); |
503 |
|
|
} |
504 |
|
|
|
505 |
|
|
|
506 |
|
|
/* |
507 |
|
|
* parse_resolvconf(): |
508 |
|
|
* |
509 |
|
|
* This function parses "/etc/resolv.conf" to figure out the nameserver |
510 |
|
|
* and domain used by the host. |
511 |
|
|
*/ |
512 |
|
|
static void parse_resolvconf(struct net *net) |
513 |
|
|
{ |
514 |
|
|
FILE *f; |
515 |
|
|
char buf[8000]; |
516 |
|
|
size_t len; |
517 |
|
|
int res; |
518 |
|
|
unsigned int i, start; |
519 |
|
|
|
520 |
|
|
/* |
521 |
|
|
* This is a very ugly hack, which tries to figure out which |
522 |
|
|
* nameserver the host uses by looking for the string 'nameserver' |
523 |
|
|
* in /etc/resolv.conf. |
524 |
|
|
* |
525 |
|
|
* This can later on be used for DHCP autoconfiguration. (TODO) |
526 |
|
|
* |
527 |
|
|
* TODO: This is hardcoded to use /etc/resolv.conf. Not all |
528 |
|
|
* operating systems use that filename. |
529 |
|
|
* |
530 |
|
|
* TODO: This is hardcoded for AF_INET (that is, IPv4). |
531 |
|
|
* |
532 |
|
|
* TODO: This assumes that the first nameserver listed is the |
533 |
|
|
* one to use. |
534 |
|
|
*/ |
535 |
|
|
f = fopen("/etc/resolv.conf", "r"); |
536 |
|
|
if (f == NULL) |
537 |
|
|
return; |
538 |
|
|
|
539 |
|
|
/* TODO: get rid of the hardcoded values */ |
540 |
|
|
memset(buf, 0, sizeof(buf)); |
541 |
|
|
len = fread(buf, 1, sizeof(buf) - 100, f); |
542 |
|
|
fclose(f); |
543 |
|
|
buf[sizeof(buf) - 1] = '\0'; |
544 |
|
|
|
545 |
|
|
for (i=0; i<len; i++) |
546 |
|
|
if (strncmp(buf+i, "nameserver", 10) == 0) { |
547 |
|
|
char *p; |
548 |
|
|
|
549 |
|
|
/* |
550 |
|
|
* "nameserver" (1 or more whitespace) |
551 |
|
|
* "x.y.z.w" (non-digit) |
552 |
|
|
*/ |
553 |
|
|
|
554 |
|
|
/* debug("found nameserver at offset %i\n", i); */ |
555 |
|
|
i += 10; |
556 |
|
|
while (i<len && (buf[i]==' ' || buf[i]=='\t')) |
557 |
|
|
i++; |
558 |
|
|
if (i >= len) |
559 |
|
|
break; |
560 |
|
|
start = i; |
561 |
|
|
|
562 |
|
|
p = buf+start; |
563 |
|
|
while ((*p >= '0' && *p <= '9') || *p == '.') |
564 |
|
|
p++; |
565 |
|
|
*p = '\0'; |
566 |
|
|
|
567 |
|
|
#ifdef HAVE_INET_PTON |
568 |
|
|
res = inet_pton(AF_INET, buf + start, |
569 |
|
|
&net->nameserver_ipv4); |
570 |
|
|
#else |
571 |
|
|
res = inet_aton(buf + start, &net->nameserver_ipv4); |
572 |
|
|
#endif |
573 |
|
|
if (res < 1) |
574 |
|
|
break; |
575 |
|
|
|
576 |
|
|
net->nameserver_known = 1; |
577 |
|
|
break; |
578 |
|
|
} |
579 |
|
|
|
580 |
|
|
for (i=0; i<len; i++) |
581 |
|
|
if (strncmp(buf+i, "domain", 6) == 0) { |
582 |
|
|
/* "domain" (1 or more whitespace) domain_name */ |
583 |
|
|
i += 6; |
584 |
|
|
while (i<len && (buf[i]==' ' || buf[i]=='\t')) |
585 |
|
|
i++; |
586 |
|
|
if (i >= len) |
587 |
|
|
break; |
588 |
|
|
|
589 |
|
|
start = i; |
590 |
|
|
while (i<len && buf[i]!='\n' && buf[i]!='\r') |
591 |
|
|
i++; |
592 |
|
|
if (i < len) |
593 |
|
|
buf[i] = '\0'; |
594 |
|
|
/* fatal("DOMAIN='%s'\n", buf + start); */ |
595 |
|
|
net->domain_name = strdup(buf + start); |
596 |
|
|
break; |
597 |
|
|
} |
598 |
|
|
} |
599 |
|
|
|
600 |
|
|
|
601 |
|
|
/* |
602 |
|
|
* net_add_nic(): |
603 |
|
|
* |
604 |
|
|
* Add a NIC to a network. (All NICs on a network will see each other's |
605 |
|
|
* packets.) |
606 |
|
|
*/ |
607 |
|
|
void net_add_nic(struct net *net, void *extra, unsigned char *macaddr) |
608 |
|
|
{ |
609 |
|
|
if (net == NULL) |
610 |
|
|
return; |
611 |
|
|
|
612 |
|
|
if (extra == NULL) { |
613 |
|
|
fprintf(stderr, "net_add_nic(): extra = NULL\n"); |
614 |
|
|
exit(1); |
615 |
|
|
} |
616 |
|
|
|
617 |
|
|
net->n_nics ++; |
618 |
|
|
net->nic_extra = realloc(net->nic_extra, sizeof(void *) |
619 |
|
|
* net->n_nics); |
620 |
|
|
if (net->nic_extra == NULL) { |
621 |
|
|
fprintf(stderr, "net_add_nic(): out of memory\n"); |
622 |
|
|
exit(1); |
623 |
|
|
} |
624 |
|
|
|
625 |
|
|
net->nic_extra[net->n_nics - 1] = extra; |
626 |
|
|
} |
627 |
|
|
|
628 |
|
|
|
629 |
|
|
/* |
630 |
|
|
* net_gateway_init(): |
631 |
|
|
* |
632 |
|
|
* This function creates a "gateway" machine (for example at IPv4 address |
633 |
|
|
* 10.0.0.254, if the net is 10.0.0.0/8), which acts as a gateway/router/ |
634 |
|
|
* nameserver etc. |
635 |
|
|
*/ |
636 |
|
|
static void net_gateway_init(struct net *net) |
637 |
|
|
{ |
638 |
|
|
unsigned char *p = (void *) &net->netmask_ipv4; |
639 |
|
|
uint32_t x; |
640 |
|
|
int xl; |
641 |
|
|
|
642 |
|
|
x = (p[0] << 24) + (p[1] << 16) + (p[2] << 8) + p[3]; |
643 |
|
|
xl = 32 - net->netmask_ipv4_len; |
644 |
|
|
if (xl > 8) |
645 |
|
|
xl = 8; |
646 |
|
|
x |= ((1 << xl) - 1) & ~1; |
647 |
|
|
|
648 |
|
|
net->gateway_ipv4_addr[0] = x >> 24; |
649 |
|
|
net->gateway_ipv4_addr[1] = x >> 16; |
650 |
|
|
net->gateway_ipv4_addr[2] = x >> 8; |
651 |
|
|
net->gateway_ipv4_addr[3] = x; |
652 |
|
|
|
653 |
|
|
net->gateway_ethernet_addr[0] = 0x60; |
654 |
|
|
net->gateway_ethernet_addr[1] = 0x50; |
655 |
|
|
net->gateway_ethernet_addr[2] = 0x40; |
656 |
|
|
net->gateway_ethernet_addr[3] = 0x30; |
657 |
|
|
net->gateway_ethernet_addr[4] = 0x20; |
658 |
|
|
net->gateway_ethernet_addr[5] = 0x10; |
659 |
|
|
} |
660 |
|
|
|
661 |
|
|
|
662 |
|
|
/* |
663 |
|
|
* net_dumpinfo(): |
664 |
|
|
* |
665 |
|
|
* Called from the debugger's "machine" command, to print some info about |
666 |
|
|
* a network. |
667 |
|
|
*/ |
668 |
|
|
void net_dumpinfo(struct net *net) |
669 |
|
|
{ |
670 |
|
|
int iadd = DEBUG_INDENTATION; |
671 |
|
|
struct remote_net *rnp; |
672 |
|
|
|
673 |
|
|
debug("net: simulating "); |
674 |
|
|
|
675 |
|
|
net_debugaddr(&net->netmask_ipv4, NET_ADDR_IPV4); |
676 |
|
|
debug("/%i", net->netmask_ipv4_len); |
677 |
|
|
|
678 |
|
|
debug(" (max outgoing: TCP=%i, UDP=%i)\n", |
679 |
|
|
MAX_TCP_CONNECTIONS, MAX_UDP_CONNECTIONS); |
680 |
|
|
|
681 |
|
|
debug_indentation(iadd); |
682 |
|
|
|
683 |
|
|
debug("simulated gateway: "); |
684 |
|
|
net_debugaddr(&net->gateway_ipv4_addr, NET_ADDR_IPV4); |
685 |
|
|
debug(" ("); |
686 |
|
|
net_debugaddr(&net->gateway_ethernet_addr, NET_ADDR_ETHERNET); |
687 |
|
|
debug(")\n"); |
688 |
|
|
|
689 |
|
|
debug_indentation(iadd); |
690 |
|
|
if (!net->nameserver_known) { |
691 |
|
|
debug("(could not determine nameserver)"); |
692 |
|
|
} else { |
693 |
|
|
debug("using nameserver "); |
694 |
|
|
net_debugaddr(&net->nameserver_ipv4, NET_ADDR_IPV4); |
695 |
|
|
} |
696 |
|
|
if (net->domain_name != NULL && net->domain_name[0]) |
697 |
|
|
debug(", domain \"%s\"", net->domain_name); |
698 |
|
|
debug("\n"); |
699 |
|
|
debug_indentation(-iadd); |
700 |
|
|
|
701 |
|
|
rnp = net->remote_nets; |
702 |
|
|
if (net->local_port != 0) |
703 |
|
|
debug("distributed network: local port = %i\n", |
704 |
|
|
net->local_port); |
705 |
|
|
debug_indentation(iadd); |
706 |
|
|
while (rnp != NULL) { |
707 |
|
|
debug("remote \"%s\": ", rnp->name); |
708 |
|
|
net_debugaddr(&rnp->ipv4_addr, NET_ADDR_IPV4); |
709 |
|
|
debug(" port %i\n", rnp->portnr); |
710 |
|
|
rnp = rnp->next; |
711 |
|
|
} |
712 |
|
|
debug_indentation(-iadd); |
713 |
|
|
|
714 |
|
|
debug_indentation(-iadd); |
715 |
|
|
} |
716 |
|
|
|
717 |
|
|
|
718 |
|
|
/* |
719 |
|
|
* net_init(): |
720 |
|
|
* |
721 |
|
|
* This function creates a network, and returns a pointer to it. |
722 |
|
|
* |
723 |
|
|
* ipv4addr should be something like "10.0.0.0", netipv4len = 8. |
724 |
|
|
* |
725 |
|
|
* If n_remote is more than zero, remote should be a pointer to an array |
726 |
|
|
* of strings of the following format: "host:portnr". |
727 |
|
|
* |
728 |
|
|
* Network settings are registered if settings_prefix is non-NULL. |
729 |
|
|
* (The one calling net_init() is also responsible for calling net_deinit().) |
730 |
|
|
* |
731 |
|
|
* On failure, exit() is called. |
732 |
|
|
*/ |
733 |
|
|
struct net *net_init(struct emul *emul, int init_flags, |
734 |
|
|
const char *ipv4addr, int netipv4len, |
735 |
|
|
char **remote, int n_remote, int local_port, |
736 |
|
|
const char *settings_prefix) |
737 |
|
|
{ |
738 |
|
|
struct net *net; |
739 |
|
|
int res; |
740 |
|
|
|
741 |
|
|
net = malloc(sizeof(struct net)); |
742 |
|
|
if (net == NULL) { |
743 |
|
|
fprintf(stderr, "net_init(): out of memory\n"); |
744 |
|
|
exit(1); |
745 |
|
|
} |
746 |
|
|
|
747 |
|
|
memset(net, 0, sizeof(struct net)); |
748 |
|
|
|
749 |
|
|
/* Set the back pointer: */ |
750 |
|
|
net->emul = emul; |
751 |
|
|
|
752 |
|
|
/* Sane defaults: */ |
753 |
|
|
net->timestamp = 0; |
754 |
|
|
net->first_ethernet_packet = net->last_ethernet_packet = NULL; |
755 |
|
|
|
756 |
|
|
#ifdef HAVE_INET_PTON |
757 |
|
|
res = inet_pton(AF_INET, ipv4addr, &net->netmask_ipv4); |
758 |
|
|
#else |
759 |
|
|
res = inet_aton(ipv4addr, &net->netmask_ipv4); |
760 |
|
|
#endif |
761 |
|
|
if (res < 1) { |
762 |
|
|
fprintf(stderr, "net_init(): could not parse IPv4 address" |
763 |
|
|
" '%s'\n", ipv4addr); |
764 |
|
|
exit(1); |
765 |
|
|
} |
766 |
|
|
|
767 |
|
|
if (netipv4len < 1 || netipv4len > 30) { |
768 |
|
|
fprintf(stderr, "net_init(): extremely weird ipv4 " |
769 |
|
|
"network length (%i)\n", netipv4len); |
770 |
|
|
exit(1); |
771 |
|
|
} |
772 |
|
|
net->netmask_ipv4_len = netipv4len; |
773 |
|
|
|
774 |
|
|
net->nameserver_known = 0; |
775 |
|
|
net->domain_name = ""; |
776 |
|
|
parse_resolvconf(net); |
777 |
|
|
|
778 |
|
|
/* Distributed network? Then add remote hosts: */ |
779 |
|
|
if (local_port != 0) { |
780 |
|
|
struct sockaddr_in si_self; |
781 |
|
|
|
782 |
|
|
net->local_port = local_port; |
783 |
|
|
net->local_port_socket = socket(AF_INET, SOCK_DGRAM, 0); |
784 |
|
|
if (net->local_port_socket < 0) { |
785 |
|
|
perror("socket"); |
786 |
|
|
exit(1); |
787 |
|
|
} |
788 |
|
|
|
789 |
|
|
memset((char *)&si_self, sizeof(si_self), 0); |
790 |
|
|
si_self.sin_family = AF_INET; |
791 |
|
|
si_self.sin_port = htons(local_port); |
792 |
|
|
si_self.sin_addr.s_addr = htonl(INADDR_ANY); |
793 |
|
|
if (bind(net->local_port_socket, (struct sockaddr *)&si_self, |
794 |
|
|
sizeof(si_self)) < 0) { |
795 |
|
|
perror("bind"); |
796 |
|
|
exit(1); |
797 |
|
|
} |
798 |
|
|
|
799 |
|
|
/* Set the socket to non-blocking: */ |
800 |
|
|
res = fcntl(net->local_port_socket, F_GETFL); |
801 |
|
|
fcntl(net->local_port_socket, F_SETFL, res | O_NONBLOCK); |
802 |
|
|
} |
803 |
|
|
if (n_remote != 0) { |
804 |
|
|
struct remote_net *rnp; |
805 |
|
|
while ((n_remote--) != 0) { |
806 |
|
|
struct hostent *hp; |
807 |
|
|
|
808 |
|
|
/* debug("adding '%s'\n", remote[n_remote]); */ |
809 |
|
|
rnp = malloc(sizeof(struct remote_net)); |
810 |
|
|
memset(rnp, 0, sizeof(struct remote_net)); |
811 |
|
|
|
812 |
|
|
rnp->next = net->remote_nets; |
813 |
|
|
net->remote_nets = rnp; |
814 |
|
|
|
815 |
|
|
rnp->name = strdup(remote[n_remote]); |
816 |
|
|
if (strchr(rnp->name, ':') != NULL) |
817 |
|
|
strchr(rnp->name, ':')[0] = '\0'; |
818 |
|
|
|
819 |
|
|
hp = gethostbyname(rnp->name); |
820 |
|
|
if (hp == NULL) { |
821 |
|
|
fprintf(stderr, "could not resolve '%s'\n", |
822 |
|
|
rnp->name); |
823 |
|
|
exit(1); |
824 |
|
|
} |
825 |
|
|
memcpy(&rnp->ipv4_addr, hp->h_addr, hp->h_length); |
826 |
|
|
free(rnp->name); |
827 |
|
|
|
828 |
|
|
/* And again: */ |
829 |
|
|
rnp->name = strdup(remote[n_remote]); |
830 |
|
|
if (strchr(rnp->name, ':') == NULL) { |
831 |
|
|
fprintf(stderr, "Remote network '%s' is not " |
832 |
|
|
"'host:portnr'?\n", rnp->name); |
833 |
|
|
exit(1); |
834 |
|
|
} |
835 |
|
|
rnp->portnr = atoi(strchr(rnp->name, ':') + 1); |
836 |
|
|
} |
837 |
|
|
} |
838 |
|
|
|
839 |
|
|
if (init_flags & NET_INIT_FLAG_GATEWAY) |
840 |
|
|
net_gateway_init(net); |
841 |
|
|
|
842 |
|
|
net_dumpinfo(net); |
843 |
|
|
|
844 |
|
|
/* This is necessary when using the real network: */ |
845 |
|
|
signal(SIGPIPE, SIG_IGN); |
846 |
|
|
|
847 |
|
|
return net; |
848 |
|
|
} |
849 |
|
|
|