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/* |
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* Copyright (C) 2004-2005 Anders Gavare. All rights reserved. |
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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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* $Id: net.c,v 1.72 2005/03/14 19:14:05 debug Exp $ |
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* |
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* Emulated (ethernet / internet) network support. |
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* |
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* |
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* NOTE: This is just an ugly hack, and just barely enough to get some |
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* Internet networking up and running for the guest OS. |
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* |
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* TODO: o) TCP: fin/ack stuff, and connection time-outs and |
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* connection refused (reset on connect?), resend |
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* data to the guest OS if no ack has arrived for |
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* some time (? buffers?) |
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* http://www.tcpipguide.com/free/ |
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* t_TCPConnectionTermination-2.htm |
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* o) remove the netbsd-specific options in the tcp header (?) |
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* o) Outgoing UDP packet fragment support. |
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* o) IPv6 (outgoing, incoming, and the nameserver/gateway) |
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* o) Incoming connections |
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* o) if multiple NICs are connected to the same network, |
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* they should be able to see each other's packets, and |
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* they should have different MAC addresses! |
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* |
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* |
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* The emulated NIC has a MAC address of (for example) 10:20:30:40:50:60. |
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* From the emulated environment, the only other machine existing on the |
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* network is a "gateway" or "firewall", which has an address of |
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* 60:50:40:30:20:10. This module (net.c) contains the emulation of that |
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* gateway. It works like a NAT firewall, but emulated in userland software. |
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* |
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* The gateway uses IPv4 address 10.0.0.254, the guest OS (inside the |
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* emulator) could use any 10.x.x.x address, except 10.0.0.254. A suitable |
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* choice is, for example 10.0.0.1. |
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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 controller, so that if multiple controllers |
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* are emulated concurrently, they will not get packets that aren't meant |
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* for some other controller. |
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* |
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* |
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* <------------------ a network ------------------------------> |
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* ^ ^ ^ |
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* | | | |
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* a NIC connected another NIC the gateway |
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* to the network | |
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* v |
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* outside |
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* world |
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* |
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* The gateway isn't connected as a NIC, but is an "implicit" machine on the |
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* network. |
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* |
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* (See http://www.sinclair.org.au/keith/networking/vendor.html for a list |
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* of ethernet MAC assignments.) |
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*/ |
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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/time.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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|
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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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|
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|
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/* #define debug fatal */ |
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|
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|
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#define ADDR_IPV4 1 |
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#define ADDR_IPV6 2 |
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#define ADDR_ETHERNET 3 |
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|
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|
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/* |
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* net_debugaddr(): |
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* |
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* Print an address using debug(). |
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*/ |
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static void net_debugaddr(void *ipv4_addr, int type) |
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{ |
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int i; |
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unsigned char *p = ipv4_addr; |
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|
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switch (type) { |
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case ADDR_IPV4: |
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for (i=0; i<4; i++) |
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debug("%s%i", i? "." : "", p[i]); |
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break; |
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case ADDR_IPV6: |
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for (i=0; i<16; i+=2) |
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debug("%s%4x", i? ":" : "", p[i] * 256 + p[i+1]); |
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break; |
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case ADDR_ETHERNET: |
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for (i=0; i<6; i++) |
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debug("%s%02x", i? ":" : "", p[i]); |
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break; |
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default: |
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fatal("( net_debugaddr(): UNIMPLEMTED type %i )\n", type); |
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} |
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} |
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|
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|
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/* |
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* net_generate_unique_mac(): |
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* |
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* Generate a "unique" serial number for a machine. The machine's serial |
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* number is combined with the machine's current number of NICs to form a |
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* more-or-less valid MAC address. |
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* |
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* The return value (6 bytes) are written to macbuf. |
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*/ |
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void net_generate_unique_mac(struct machine *machine, unsigned char *macbuf) |
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{ |
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int x, y; |
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|
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if (macbuf == NULL || machine == NULL) { |
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fatal("**\n** net_generate_unique_mac(): NULL ptr\n**\n"); |
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return; |
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} |
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|
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x = machine->serial_nr; |
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y = machine->nr_of_nics; |
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|
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/* |
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* TODO: What is a good starting value? Right now, it looks like this: |
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* |
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* +-----------+-------------------+-------------+-------------+ |
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* | 16 bits | 16 bits machine | 12 bits | 4 bits of | |
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* | fixed | serial nr | NIC nr(*) | zeroes | |
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* +-----------+-------------------+-------------+-------------+ |
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* |
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* (*) = almost |
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*/ |
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macbuf[0] = 0x10; |
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macbuf[1] = 0x20; |
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macbuf[2] = x >> 8; |
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macbuf[3] = x & 255; |
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macbuf[4] = y / 15; |
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macbuf[5] = (y % 15) * 0x10 + 0x10; |
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|
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/* TODO: Remember the mac addresses somewhere? */ |
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machine->nr_of_nics ++; |
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} |
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|
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|
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/* |
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* net_ip_checksum(): |
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* |
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* Fill in an IP header checksum. (This works for ICMP too.) |
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* chksumoffset should be 10 for IP headers, and len = 20. |
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* For ICMP packets, chksumoffset = 2 and len = length of the ICMP packet. |
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*/ |
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void net_ip_checksum(unsigned char *ip_header, int chksumoffset, int len) |
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{ |
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int i; |
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uint32_t sum = 0; |
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|
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for (i=0; i<len; i+=2) |
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if (i != chksumoffset) { |
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uint16_t w = (ip_header[i] << 8) + ip_header[i+1]; |
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sum += w; |
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while (sum > 65535) { |
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int to_add = sum >> 16; |
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sum = (sum & 0xffff) + to_add; |
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} |
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} |
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|
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sum ^= 0xffff; |
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ip_header[chksumoffset + 0] = sum >> 8; |
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ip_header[chksumoffset + 1] = sum & 0xff; |
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} |
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|
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|
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/* |
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* net_ip_tcp_checksum(): |
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* |
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* Fill in a TCP header checksum. This differs slightly from the IP |
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* checksum. The checksum is calculated on a pseudo header, the actual |
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* TCP header, and the data. This is what the pseudo header looks like: |
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* |
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* uint32_t srcaddr; |
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* uint32_t dstaddr; |
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* uint16_t protocol; (= 6 for tcp) |
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* uint16_t tcp_len; |
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* |
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* tcp_len is length of header PLUS data. The psedo header is created |
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* internally here, and does not need to be supplied by the caller. |
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*/ |
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static void net_ip_tcp_checksum(unsigned char *tcp_header, int chksumoffset, |
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int tcp_len, unsigned char *srcaddr, unsigned char *dstaddr, |
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int udpflag) |
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{ |
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int i, pad = 0; |
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unsigned char pseudoh[12]; |
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uint32_t sum = 0; |
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|
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memcpy(pseudoh + 0, srcaddr, 4); |
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memcpy(pseudoh + 4, dstaddr, 4); |
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pseudoh[8] = 0x00; |
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pseudoh[9] = udpflag? 17 : 6; |
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pseudoh[10] = tcp_len >> 8; |
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pseudoh[11] = tcp_len & 255; |
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|
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for (i=0; i<12; i+=2) { |
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uint16_t w = (pseudoh[i] << 8) + pseudoh[i+1]; |
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sum += w; |
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while (sum > 65535) { |
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int to_add = sum >> 16; |
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sum = (sum & 0xffff) + to_add; |
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} |
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} |
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|
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if (tcp_len & 1) { |
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tcp_len ++; |
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pad = 1; |
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} |
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|
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for (i=0; i<tcp_len; i+=2) |
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if (i != chksumoffset) { |
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uint16_t w; |
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if (!pad || i < tcp_len-2) |
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w = (tcp_header[i] << 8) + tcp_header[i+1]; |
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else |
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w = (tcp_header[i] << 8) + 0x00; |
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sum += w; |
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while (sum > 65535) { |
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int to_add = sum >> 16; |
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sum = (sum & 0xffff) + to_add; |
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} |
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} |
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|
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sum ^= 0xffff; |
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tcp_header[chksumoffset + 0] = sum >> 8; |
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tcp_header[chksumoffset + 1] = sum & 0xff; |
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} |
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|
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|
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/* |
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* net_allocate_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 zeroed), |
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* and the data, extra, and len fields of the link are set. |
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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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static struct ethernet_packet_link *net_allocate_packet_link( |
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struct net *net, void *extra, int len) |
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{ |
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struct ethernet_packet_link *lp; |
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|
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lp = malloc(sizeof(struct ethernet_packet_link)); |
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if (lp == NULL) { |
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fprintf(stderr, "net_allocate_packet_link(): out of memory\n"); |
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exit(1); |
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} |
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|
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/* memset(lp, 0, sizeof(struct ethernet_packet_link)); */ |
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|
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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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fprintf(stderr, "net_allocate_packet_link(): out of memory\n"); |
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exit(1); |
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} |
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lp->next = NULL; |
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|
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/* TODO: maybe this is not necessary: */ |
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memset(lp->data, 0, len); |
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|
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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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|
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return lp; |
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} |
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|
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|
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/* |
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* net_ip_icmp(): |
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* |
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* Handle an ICMP packet. |
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* |
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* The IP header (at offset 14) could look something like |
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* |
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* ver=45 tos=00 len=0054 id=001a ofs=0000 ttl=ff p=01 sum=a87e |
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* src=0a000005 dst=03050607 |
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* |
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* and the ICMP specific data (beginning at offset 34): |
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* |
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* type=08 code=00 chksum=b8bf |
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* 000c0008d5cee94089190c0008090a0b |
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* 0c0d0e0f101112131415161718191a1b |
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* 1c1d1e1f202122232425262728292a2b |
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* 2c2d2e2f3031323334353637 |
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*/ |
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static void net_ip_icmp(struct net *net, void *extra, |
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unsigned char *packet, int len) |
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{ |
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int type; |
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struct ethernet_packet_link *lp; |
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|
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type = packet[34]; |
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|
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switch (type) { |
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case 8: /* ECHO request */ |
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debug("[ ICMP echo ]\n"); |
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lp = net_allocate_packet_link(net, extra, len); |
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|
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/* Copy the old packet first: */ |
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memcpy(lp->data, packet, len); |
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|
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/* Switch to and from ethernet addresses: */ |
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memcpy(lp->data + 0, packet + 6, 6); |
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memcpy(lp->data + 6, packet + 0, 6); |
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|
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/* Switch to and from IP addresses: */ |
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memcpy(lp->data + 26, packet + 30, 4); |
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memcpy(lp->data + 30, packet + 26, 4); |
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|
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/* Change from echo REQUEST to echo REPLY: */ |
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lp->data[34] = 0x00; |
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|
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/* Decrease the TTL to a low value: */ |
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lp->data[22] = 2; |
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|
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/* Recalculate ICMP checksum: */ |
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net_ip_checksum(lp->data + 34, 2, len - 34); |
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|
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/* Recalculate IP header checksum: */ |
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net_ip_checksum(lp->data + 14, 10, 20); |
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|
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break; |
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default: |
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fatal("[ net: ICMP type %i not yet implemented ]\n", type); |
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} |
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} |
381 |
|
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|
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/* |
384 |
* tcp_closeconnection(): |
385 |
* |
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* Helper function which closes down a TCP connection completely. |
387 |
*/ |
388 |
static void tcp_closeconnection(struct net *net, int con_id) |
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{ |
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close(net->tcp_connections[con_id].socket); |
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net->tcp_connections[con_id].state = TCP_OUTSIDE_DISCONNECTED; |
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net->tcp_connections[con_id].in_use = 0; |
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net->tcp_connections[con_id].incoming_buf_len = 0; |
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} |
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|
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|
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/* |
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* net_ip_tcp_connectionreply(): |
399 |
* |
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* When changing from state _TRYINGTOCONNECT to _CONNECTED, then this |
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* function should be called with connecting set to 1. |
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* |
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* To send a generic ack reply, set connecting to 0. |
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* |
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* To send data (PSH), set data to non-NULL and datalen to the length. |
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* |
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* This creates an ethernet packet for the guest OS with an ACK to the |
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* initial SYN packet. |
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*/ |
410 |
static void net_ip_tcp_connectionreply(struct net *net, void *extra, |
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int con_id, int connecting, unsigned char *data, int datalen, int rst) |
412 |
{ |
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struct ethernet_packet_link *lp; |
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int tcp_length, ip_len, option_len = 20; |
415 |
|
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if (connecting) |
417 |
net->tcp_connections[con_id].outside_acknr = |
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net->tcp_connections[con_id].inside_seqnr + 1; |
419 |
|
420 |
net->tcp_connections[con_id].tcp_id ++; |
421 |
tcp_length = 20 + option_len + datalen; |
422 |
ip_len = 20 + tcp_length; |
423 |
lp = net_allocate_packet_link(net, extra, 14 + ip_len); |
424 |
|
425 |
/* Ethernet header: */ |
426 |
memcpy(lp->data + 0, net->tcp_connections[con_id].ethernet_address, 6); |
427 |
memcpy(lp->data + 6, net->gateway_ethernet_addr, 6); |
428 |
lp->data[12] = 0x08; /* IP = 0x0800 */ |
429 |
lp->data[13] = 0x00; |
430 |
|
431 |
/* IP header: */ |
432 |
lp->data[14] = 0x45; /* ver */ |
433 |
lp->data[15] = 0x10; /* tos */ |
434 |
lp->data[16] = ip_len >> 8; |
435 |
lp->data[17] = ip_len & 0xff; |
436 |
lp->data[18] = net->tcp_connections[con_id].tcp_id >> 8; |
437 |
lp->data[19] = net->tcp_connections[con_id].tcp_id & 0xff; |
438 |
lp->data[20] = 0x40; /* don't fragment */ |
439 |
lp->data[21] = 0x00; |
440 |
lp->data[22] = 0x40; /* ttl */ |
441 |
lp->data[23] = 6; /* p = TCP */ |
442 |
memcpy(lp->data + 26, net->tcp_connections[con_id]. |
443 |
outside_ip_address, 4); |
444 |
memcpy(lp->data + 30, net->tcp_connections[con_id]. |
445 |
inside_ip_address, 4); |
446 |
net_ip_checksum(lp->data + 14, 10, 20); |
447 |
|
448 |
/* TCP header and options at offset 34: */ |
449 |
lp->data[34] = net->tcp_connections[con_id].outside_tcp_port >> 8; |
450 |
lp->data[35] = net->tcp_connections[con_id].outside_tcp_port & 0xff; |
451 |
lp->data[36] = net->tcp_connections[con_id].inside_tcp_port >> 8; |
452 |
lp->data[37] = net->tcp_connections[con_id].inside_tcp_port & 0xff; |
453 |
lp->data[38] = (net->tcp_connections[con_id]. |
454 |
outside_seqnr >> 24) & 0xff; |
455 |
lp->data[39] = (net->tcp_connections[con_id]. |
456 |
outside_seqnr >> 16) & 0xff; |
457 |
lp->data[40] = (net->tcp_connections[con_id]. |
458 |
outside_seqnr >> 8) & 0xff; |
459 |
lp->data[41] = net->tcp_connections[con_id]. |
460 |
outside_seqnr & 0xff; |
461 |
lp->data[42] = (net->tcp_connections[con_id]. |
462 |
outside_acknr >> 24) & 0xff; |
463 |
lp->data[43] = (net->tcp_connections[con_id]. |
464 |
outside_acknr >> 16) & 0xff; |
465 |
lp->data[44] = (net->tcp_connections[con_id]. |
466 |
outside_acknr >> 8) & 0xff; |
467 |
lp->data[45] = net->tcp_connections[con_id].outside_acknr & 0xff; |
468 |
|
469 |
/* Control */ |
470 |
lp->data[46] = (option_len + 20) / 4 * 0x10; |
471 |
lp->data[47] = 0x10; /* ACK */ |
472 |
if (connecting) |
473 |
lp->data[47] |= 0x02; /* SYN */ |
474 |
if (net->tcp_connections[con_id].state == TCP_OUTSIDE_CONNECTED) |
475 |
lp->data[47] |= 0x08; /* PSH */ |
476 |
if (rst) |
477 |
lp->data[47] |= 0x04; /* RST */ |
478 |
if (net->tcp_connections[con_id].state >= TCP_OUTSIDE_DISCONNECTED) |
479 |
lp->data[47] |= 0x01; /* FIN */ |
480 |
|
481 |
/* Window */ |
482 |
lp->data[48] = 0x10; |
483 |
lp->data[49] = 0x00; |
484 |
|
485 |
/* no urgent ptr */ |
486 |
|
487 |
/* options */ |
488 |
/* TODO: HAHA, this is ugly */ |
489 |
lp->data[54] = 0x02; |
490 |
lp->data[55] = 0x04; |
491 |
lp->data[56] = 0x05; |
492 |
lp->data[57] = 0xb4; |
493 |
lp->data[58] = 0x01; |
494 |
lp->data[59] = 0x03; |
495 |
lp->data[60] = 0x03; |
496 |
lp->data[61] = 0x00; |
497 |
lp->data[62] = 0x01; |
498 |
lp->data[63] = 0x01; |
499 |
lp->data[64] = 0x08; |
500 |
lp->data[65] = 0x0a; |
501 |
lp->data[66] = (net->timestamp >> 24) & 0xff; |
502 |
lp->data[67] = (net->timestamp >> 16) & 0xff; |
503 |
lp->data[68] = (net->timestamp >> 8) & 0xff; |
504 |
lp->data[69] = net->timestamp & 0xff; |
505 |
lp->data[70] = (net->tcp_connections[con_id]. |
506 |
inside_timestamp >> 24) & 0xff; |
507 |
lp->data[71] = (net->tcp_connections[con_id]. |
508 |
inside_timestamp >> 16) & 0xff; |
509 |
lp->data[72] = (net->tcp_connections[con_id]. |
510 |
inside_timestamp >> 8) & 0xff; |
511 |
lp->data[73] = net->tcp_connections[con_id]. |
512 |
inside_timestamp & 0xff; |
513 |
|
514 |
/* data: */ |
515 |
if (data != NULL) { |
516 |
memcpy(lp->data + 74, data, datalen); |
517 |
net->tcp_connections[con_id].outside_seqnr += datalen; |
518 |
} |
519 |
|
520 |
/* Checksum: */ |
521 |
net_ip_tcp_checksum(lp->data + 34, 16, tcp_length, |
522 |
lp->data + 26, lp->data + 30, 0); |
523 |
|
524 |
#if 0 |
525 |
{ |
526 |
int i; |
527 |
fatal("[ net_ip_tcp_connectionreply(%i): ", connecting); |
528 |
for (i=0; i<ip_len+14; i++) |
529 |
fatal("%02x", lp->data[i]); |
530 |
fatal(" ]\n"); |
531 |
} |
532 |
#endif |
533 |
|
534 |
if (connecting) |
535 |
net->tcp_connections[con_id].outside_seqnr ++; |
536 |
} |
537 |
|
538 |
|
539 |
/* |
540 |
* net_ip_tcp(): |
541 |
* |
542 |
* Handle a TCP packet comming from the emulated OS. |
543 |
* |
544 |
* The IP header (at offset 14) could look something like |
545 |
* |
546 |
* ver=45 tos=00 len=003c id=0006 ofs=0000 ttl=40 p=11 sum=b798 |
547 |
* src=0a000001 dst=c1abcdef |
548 |
* |
549 |
* TCP header, at offset 34: |
550 |
* |
551 |
* srcport=fffe dstport=0015 seqnr=af419a1d acknr=00000000 |
552 |
* control=a002 window=4000 checksum=fe58 urgent=0000 |
553 |
* and then "options and padding" and then data. |
554 |
* (020405b4010303000101080a0000000000000000) |
555 |
* |
556 |
* See the following URLs for good descriptions of TCP: |
557 |
* |
558 |
* http://www.networksorcery.com/enp/protocol/tcp.htm |
559 |
* http://www.tcpipguide.com/free/t_TCPIPTransmissionControlProtocolTCP.htm |
560 |
*/ |
561 |
static void net_ip_tcp(struct net *net, void *extra, |
562 |
unsigned char *packet, int len) |
563 |
{ |
564 |
int con_id, free_con_id, i, res; |
565 |
int srcport, dstport, data_offset, window, checksum, urgptr; |
566 |
int syn, ack, psh, rst, urg, fin; |
567 |
uint32_t seqnr, acknr; |
568 |
struct sockaddr_in remote_ip; |
569 |
fd_set rfds; |
570 |
struct timeval tv; |
571 |
int send_ofs; |
572 |
|
573 |
#if 0 |
574 |
fatal("[ net: TCP: "); |
575 |
for (i=0; i<26; i++) |
576 |
fatal("%02x", packet[i]); |
577 |
fatal(" "); |
578 |
#endif |
579 |
|
580 |
srcport = (packet[34] << 8) + packet[35]; |
581 |
dstport = (packet[36] << 8) + packet[37]; |
582 |
|
583 |
seqnr = (packet[38] << 24) + (packet[39] << 16) |
584 |
+ (packet[40] << 8) + packet[41]; |
585 |
acknr = (packet[42] << 24) + (packet[43] << 16) |
586 |
+ (packet[44] << 8) + packet[45]; |
587 |
|
588 |
#if 0 |
589 |
fatal("%i.%i.%i.%i:%i -> %i.%i.%i.%i:%i, seqnr=%lli acknr=%lli ", |
590 |
packet[26], packet[27], packet[28], packet[29], srcport, |
591 |
packet[30], packet[31], packet[32], packet[33], dstport, |
592 |
(long long)seqnr, (long long)acknr); |
593 |
#endif |
594 |
|
595 |
data_offset = (packet[46] >> 4) * 4 + 34; |
596 |
/* data_offset is now data offset within packet :-) */ |
597 |
|
598 |
urg = packet[47] & 32; |
599 |
ack = packet[47] & 16; |
600 |
psh = packet[47] & 8; |
601 |
rst = packet[47] & 4; |
602 |
syn = packet[47] & 2; |
603 |
fin = packet[47] & 1; |
604 |
window = (packet[48] << 8) + packet[49]; |
605 |
checksum = (packet[50] << 8) + packet[51]; |
606 |
urgptr = (packet[52] << 8) + packet[53]; |
607 |
|
608 |
#if 0 |
609 |
fatal(urg? "URG " : ""); |
610 |
fatal(ack? "ACK " : ""); |
611 |
fatal(psh? "PSH " : ""); |
612 |
fatal(rst? "RST " : ""); |
613 |
fatal(syn? "SYN " : ""); |
614 |
fatal(fin? "FIN " : ""); |
615 |
|
616 |
fatal("window=0x%04x checksum=0x%04x urgptr=0x%04x ", |
617 |
window, checksum, urgptr); |
618 |
|
619 |
fatal("options="); |
620 |
for (i=34+20; i<data_offset; i++) |
621 |
fatal("%02x", packet[i]); |
622 |
|
623 |
fatal(" data="); |
624 |
for (i=data_offset; i<len; i++) |
625 |
fatal("%02x", packet[i]); |
626 |
|
627 |
fatal(" ]\n"); |
628 |
#endif |
629 |
|
630 |
net_ip_tcp_checksum(packet + 34, 16, len - 34, |
631 |
packet + 26, packet + 30, 0); |
632 |
if (packet[50] * 256 + packet[51] != checksum) { |
633 |
debug("TCP: dropping packet because of checksum mismatch " |
634 |
"(0x%04x != 0x%04x)\n", packet[50] * 256 + packet[51], |
635 |
checksum); |
636 |
|
637 |
return; |
638 |
} |
639 |
|
640 |
/* Does this packet belong to a current connection? */ |
641 |
con_id = free_con_id = -1; |
642 |
for (i=0; i<MAX_TCP_CONNECTIONS; i++) { |
643 |
if (!net->tcp_connections[i].in_use) |
644 |
free_con_id = i; |
645 |
if (net->tcp_connections[i].in_use && |
646 |
net->tcp_connections[i].inside_tcp_port == srcport && |
647 |
net->tcp_connections[i].outside_tcp_port == dstport && |
648 |
memcmp(net->tcp_connections[i].inside_ip_address, |
649 |
packet + 26, 4) == 0 && |
650 |
memcmp(net->tcp_connections[i].outside_ip_address, |
651 |
packet + 30, 4) == 0) { |
652 |
con_id = i; |
653 |
break; |
654 |
} |
655 |
} |
656 |
|
657 |
/* |
658 |
* Unknown connection, and not SYN? Then drop the packet. |
659 |
* TODO: Send back RST? |
660 |
*/ |
661 |
if (con_id < 0 && !syn) { |
662 |
debug("[ net: TCP: dropping packet from unknown connection," |
663 |
" %i.%i.%i.%i:%i -> %i.%i.%i.%i:%i %s%s%s%s%s]\n", |
664 |
packet[26], packet[27], packet[28], packet[29], srcport, |
665 |
packet[30], packet[31], packet[32], packet[33], dstport, |
666 |
fin? "FIN ": "", syn? "SYN ": "", ack? "ACK ": "", |
667 |
psh? "PSH ": "", rst? "RST ": ""); |
668 |
return; |
669 |
} |
670 |
|
671 |
/* Known connection, and SYN? Then ignore the packet. */ |
672 |
if (con_id >= 0 && syn) { |
673 |
debug("[ net: TCP: ignoring redundant SYN packet from known" |
674 |
" connection, %i.%i.%i.%i:%i -> %i.%i.%i.%i:%i ]\n", |
675 |
packet[26], packet[27], packet[28], packet[29], srcport, |
676 |
packet[30], packet[31], packet[32], packet[33], dstport); |
677 |
return; |
678 |
} |
679 |
|
680 |
/* |
681 |
* A new outgoing connection? |
682 |
*/ |
683 |
if (con_id < 0 && syn) { |
684 |
debug("[ net: TCP: new outgoing connection, %i.%i.%i.%i:%i" |
685 |
" -> %i.%i.%i.%i:%i ]\n", |
686 |
packet[26], packet[27], packet[28], packet[29], srcport, |
687 |
packet[30], packet[31], packet[32], packet[33], dstport); |
688 |
|
689 |
/* Find a free connection id to use: */ |
690 |
if (free_con_id < 0) { |
691 |
#if 1 |
692 |
/* |
693 |
* TODO: Reuse the oldest one currently in use, or |
694 |
* just drop the new connection attempt? Drop for now. |
695 |
*/ |
696 |
fatal("[ TOO MANY TCP CONNECTIONS IN USE! " |
697 |
"Increase MAX_TCP_CONNECTIONS! ]\n"); |
698 |
return; |
699 |
#else |
700 |
int i; |
701 |
int64_t oldest = net-> |
702 |
tcp_connections[0].last_used_timestamp; |
703 |
free_con_id = 0; |
704 |
|
705 |
fatal("[ NO FREE TCP SLOTS, REUSING OLDEST ONE ]\n"); |
706 |
for (i=0; i<MAX_TCP_CONNECTIONS; i++) |
707 |
if (net->tcp_connections[i]. |
708 |
last_used_timestamp < oldest) { |
709 |
oldest = net->tcp_connections[i]. |
710 |
last_used_timestamp; |
711 |
free_con_id = i; |
712 |
} |
713 |
tcp_closeconnection(net, free_con_id); |
714 |
#endif |
715 |
} |
716 |
|
717 |
con_id = free_con_id; |
718 |
memset(&net->tcp_connections[con_id], 0, |
719 |
sizeof(struct tcp_connection)); |
720 |
|
721 |
memcpy(net->tcp_connections[con_id].ethernet_address, |
722 |
packet + 6, 6); |
723 |
memcpy(net->tcp_connections[con_id].inside_ip_address, |
724 |
packet + 26, 4); |
725 |
net->tcp_connections[con_id].inside_tcp_port = srcport; |
726 |
memcpy(net->tcp_connections[con_id].outside_ip_address, |
727 |
packet + 30, 4); |
728 |
net->tcp_connections[con_id].outside_tcp_port = dstport; |
729 |
|
730 |
net->tcp_connections[con_id].socket = |
731 |
socket(AF_INET, SOCK_STREAM, 0); |
732 |
if (net->tcp_connections[con_id].socket < 0) { |
733 |
fatal("[ net: TCP: socket() returned %i ]\n", |
734 |
net->tcp_connections[con_id].socket); |
735 |
return; |
736 |
} |
737 |
|
738 |
debug("[ new tcp outgoing socket=%i ]\n", |
739 |
net->tcp_connections[con_id].socket); |
740 |
|
741 |
net->tcp_connections[con_id].in_use = 1; |
742 |
|
743 |
/* Set the socket to non-blocking: */ |
744 |
res = fcntl(net->tcp_connections[con_id].socket, F_GETFL); |
745 |
fcntl(net->tcp_connections[con_id].socket, F_SETFL, |
746 |
res | O_NONBLOCK); |
747 |
|
748 |
remote_ip.sin_family = AF_INET; |
749 |
memcpy((unsigned char *)&remote_ip.sin_addr, |
750 |
net->tcp_connections[con_id].outside_ip_address, 4); |
751 |
remote_ip.sin_port = htons( |
752 |
net->tcp_connections[con_id].outside_tcp_port); |
753 |
|
754 |
res = connect(net->tcp_connections[con_id].socket, |
755 |
(struct sockaddr *)&remote_ip, sizeof(remote_ip)); |
756 |
|
757 |
/* connect can return -1, and errno = EINPROGRESS |
758 |
as we might not have connected right away. */ |
759 |
|
760 |
net->tcp_connections[con_id].state = |
761 |
TCP_OUTSIDE_TRYINGTOCONNECT; |
762 |
|
763 |
net->tcp_connections[con_id].outside_acknr = 0; |
764 |
net->tcp_connections[con_id].outside_seqnr = |
765 |
((random() & 0xffff) << 16) + (random() & 0xffff); |
766 |
} |
767 |
|
768 |
if (rst) { |
769 |
debug("[ 'rst': disconnecting TCP connection %i ]\n", con_id); |
770 |
net_ip_tcp_connectionreply(net, extra, con_id, 0, NULL, 0, 1); |
771 |
tcp_closeconnection(net, con_id); |
772 |
return; |
773 |
} |
774 |
|
775 |
if (ack && net->tcp_connections[con_id].state |
776 |
== TCP_OUTSIDE_DISCONNECTED2) { |
777 |
debug("[ 'ack': guestOS's final termination of TCP " |
778 |
"connection %i ]\n", con_id); |
779 |
|
780 |
/* Send an RST? (TODO, this is wrong...) */ |
781 |
net_ip_tcp_connectionreply(net, extra, con_id, 0, NULL, 0, 1); |
782 |
|
783 |
/* ... and forget about this connection: */ |
784 |
tcp_closeconnection(net, con_id); |
785 |
return; |
786 |
} |
787 |
|
788 |
if (fin && net->tcp_connections[con_id].state |
789 |
== TCP_OUTSIDE_DISCONNECTED) { |
790 |
debug("[ 'fin': response to outside's disconnection of " |
791 |
"TCP connection %i ]\n", con_id); |
792 |
|
793 |
/* Send an ACK: */ |
794 |
net->tcp_connections[con_id].state = TCP_OUTSIDE_CONNECTED; |
795 |
net_ip_tcp_connectionreply(net, extra, con_id, 0, NULL, 0, 0); |
796 |
net->tcp_connections[con_id].state = TCP_OUTSIDE_DISCONNECTED2; |
797 |
return; |
798 |
} |
799 |
|
800 |
if (fin) { |
801 |
debug("[ 'fin': guestOS disconnecting TCP connection %i ]\n", |
802 |
con_id); |
803 |
|
804 |
/* Send ACK: */ |
805 |
net_ip_tcp_connectionreply(net, extra, con_id, 0, NULL, 0, 0); |
806 |
net->tcp_connections[con_id].state = TCP_OUTSIDE_DISCONNECTED2; |
807 |
|
808 |
/* Return and send FIN: */ |
809 |
goto ret; |
810 |
} |
811 |
|
812 |
if (ack) { |
813 |
debug("ACK %i bytes, inside_acknr=%u outside_seqnr=%u\n", |
814 |
net->tcp_connections[con_id].incoming_buf_len, |
815 |
net->tcp_connections[con_id].inside_acknr, |
816 |
net->tcp_connections[con_id].outside_seqnr); |
817 |
net->tcp_connections[con_id].inside_acknr = acknr; |
818 |
if (net->tcp_connections[con_id].inside_acknr == |
819 |
net->tcp_connections[con_id].outside_seqnr && |
820 |
net->tcp_connections[con_id].incoming_buf_len != 0) { |
821 |
debug(" all acked\n"); |
822 |
net->tcp_connections[con_id].incoming_buf_len = 0; |
823 |
} |
824 |
} |
825 |
|
826 |
net->tcp_connections[con_id].inside_seqnr = seqnr; |
827 |
|
828 |
/* TODO: This is hardcoded for a specific NetBSD packet: */ |
829 |
if (packet[34 + 30] == 0x08 && packet[34 + 31] == 0x0a) |
830 |
net->tcp_connections[con_id].inside_timestamp = |
831 |
(packet[34 + 32 + 0] << 24) + |
832 |
(packet[34 + 32 + 1] << 16) + |
833 |
(packet[34 + 32 + 2] << 8) + |
834 |
(packet[34 + 32 + 3] << 0); |
835 |
|
836 |
|
837 |
net->timestamp ++; |
838 |
net->tcp_connections[con_id].last_used_timestamp = net->timestamp; |
839 |
|
840 |
|
841 |
if (net->tcp_connections[con_id].state != TCP_OUTSIDE_CONNECTED) { |
842 |
debug("[ not connected to outside ]\n"); |
843 |
return; |
844 |
} |
845 |
|
846 |
|
847 |
if (data_offset >= len) |
848 |
return; |
849 |
|
850 |
|
851 |
/* |
852 |
* We are here if this is a known connection, and data is to be |
853 |
* transmitted to the outside world. |
854 |
*/ |
855 |
|
856 |
send_ofs = data_offset; |
857 |
send_ofs += ((int32_t)net->tcp_connections[con_id].outside_acknr |
858 |
- (int32_t)seqnr); |
859 |
#if 1 |
860 |
debug("[ %i bytes of tcp data to be sent, beginning at seqnr %u, ", |
861 |
len - data_offset, seqnr); |
862 |
debug("outside is at acknr %u ==> %i actual bytes to be sent ]\n", |
863 |
net->tcp_connections[con_id].outside_acknr, len - send_ofs); |
864 |
#endif |
865 |
|
866 |
/* Drop outgoing packet if the guest OS' seqnr is not |
867 |
the same as we have acked. (We have missed something, perhaps.) */ |
868 |
if (seqnr != net->tcp_connections[con_id].outside_acknr) { |
869 |
debug("!! outgoing TCP packet dropped (seqnr = %u, " |
870 |
"outside_acknr = %u)\n", seqnr, |
871 |
net->tcp_connections[con_id].outside_acknr); |
872 |
goto ret; |
873 |
} |
874 |
|
875 |
if (len - send_ofs > 0) { |
876 |
/* Is the socket available for output? */ |
877 |
FD_ZERO(&rfds); /* write */ |
878 |
FD_SET(net->tcp_connections[con_id].socket, &rfds); |
879 |
tv.tv_sec = tv.tv_usec = 0; |
880 |
errno = 0; |
881 |
res = select(net->tcp_connections[con_id].socket+1, |
882 |
NULL, &rfds, NULL, &tv); |
883 |
if (res < 1) { |
884 |
net->tcp_connections[con_id].state = |
885 |
TCP_OUTSIDE_DISCONNECTED; |
886 |
debug("[ TCP: disconnect on select for writing ]\n"); |
887 |
goto ret; |
888 |
} |
889 |
|
890 |
res = write(net->tcp_connections[con_id].socket, |
891 |
packet + send_ofs, len - send_ofs); |
892 |
|
893 |
if (res > 0) { |
894 |
net->tcp_connections[con_id].outside_acknr += res; |
895 |
} else if (errno == EAGAIN) { |
896 |
/* Just ignore this attempt. */ |
897 |
return; |
898 |
} else { |
899 |
debug("[ error writing %i bytes to TCP connection %i:" |
900 |
" errno = %i ]\n", len - send_ofs, con_id, errno); |
901 |
net->tcp_connections[con_id].state = |
902 |
TCP_OUTSIDE_DISCONNECTED; |
903 |
debug("[ TCP: disconnect on write() ]\n"); |
904 |
goto ret; |
905 |
} |
906 |
} |
907 |
|
908 |
ret: |
909 |
/* Send an ACK (or FIN) to the guest OS: */ |
910 |
net_ip_tcp_connectionreply(net, extra, con_id, 0, NULL, 0, 0); |
911 |
} |
912 |
|
913 |
|
914 |
/* |
915 |
* net_ip_udp(): |
916 |
* |
917 |
* Handle a UDP packet. |
918 |
* |
919 |
* (See http://www.networksorcery.com/enp/protocol/udp.htm.) |
920 |
* |
921 |
* The IP header (at offset 14) could look something like |
922 |
* |
923 |
* ver=45 tos=00 len=003c id=0006 ofs=0000 ttl=40 p=11 sum=b798 |
924 |
* src=0a000001 dst=c1abcdef |
925 |
* |
926 |
* and the UDP data (beginning at offset 34): |
927 |
* |
928 |
* srcport=fffc dstport=0035 length=0028 chksum=76b6 |
929 |
* 43e20100000100000000000003667470066e6574627364036f726700001c0001 |
930 |
*/ |
931 |
static void net_ip_udp(struct net *net, void *extra, |
932 |
unsigned char *packet, int len) |
933 |
{ |
934 |
int con_id, free_con_id, i, srcport, dstport, udp_len; |
935 |
ssize_t res; |
936 |
struct sockaddr_in remote_ip; |
937 |
|
938 |
if ((packet[20] & 0x3f) != 0) { |
939 |
fatal("[ net_ip_udp(): WARNING! fragmented UDP " |
940 |
"packet, TODO ]\n"); |
941 |
return; |
942 |
} |
943 |
|
944 |
srcport = (packet[34] << 8) + packet[35]; |
945 |
dstport = (packet[36] << 8) + packet[37]; |
946 |
udp_len = (packet[38] << 8) + packet[39]; |
947 |
/* chksum at offset 40 and 41 */ |
948 |
|
949 |
debug("[ net: UDP: "); |
950 |
debug("srcport=%i dstport=%i len=%i ", srcport, dstport, udp_len); |
951 |
for (i=42; i<len; i++) { |
952 |
if (packet[i] >= ' ' && packet[i] < 127) |
953 |
debug("%c", packet[i]); |
954 |
else |
955 |
debug("[%02x]", packet[i]); |
956 |
} |
957 |
debug(" ]\n"); |
958 |
|
959 |
/* Is this "connection" new, or a currently ongoing one? */ |
960 |
con_id = free_con_id = -1; |
961 |
for (i=0; i<MAX_UDP_CONNECTIONS; i++) { |
962 |
if (!net->udp_connections[i].in_use) |
963 |
free_con_id = i; |
964 |
if (net->udp_connections[i].in_use && |
965 |
net->udp_connections[i].inside_udp_port == srcport && |
966 |
net->udp_connections[i].outside_udp_port == dstport && |
967 |
memcmp(net->udp_connections[i].inside_ip_address, |
968 |
packet + 26, 4) == 0 && |
969 |
memcmp(net->udp_connections[i].outside_ip_address, |
970 |
packet + 30, 4) == 0) { |
971 |
con_id = i; |
972 |
break; |
973 |
} |
974 |
} |
975 |
|
976 |
debug("&& UDP connection is "); |
977 |
if (con_id >= 0) |
978 |
debug("ONGOING"); |
979 |
else { |
980 |
debug("NEW"); |
981 |
if (free_con_id < 0) { |
982 |
int i; |
983 |
int64_t oldest = net-> |
984 |
udp_connections[0].last_used_timestamp; |
985 |
free_con_id = 0; |
986 |
|
987 |
debug(", NO FREE SLOTS, REUSING OLDEST ONE"); |
988 |
for (i=0; i<MAX_UDP_CONNECTIONS; i++) |
989 |
if (net->udp_connections[i]. |
990 |
last_used_timestamp < oldest) { |
991 |
oldest = net->udp_connections[i]. |
992 |
last_used_timestamp; |
993 |
free_con_id = i; |
994 |
} |
995 |
close(net->udp_connections[free_con_id].socket); |
996 |
} |
997 |
con_id = free_con_id; |
998 |
memset(&net->udp_connections[con_id], 0, |
999 |
sizeof(struct udp_connection)); |
1000 |
|
1001 |
memcpy(net->udp_connections[con_id].ethernet_address, |
1002 |
packet + 6, 6); |
1003 |
memcpy(net->udp_connections[con_id].inside_ip_address, |
1004 |
packet + 26, 4); |
1005 |
net->udp_connections[con_id].inside_udp_port = srcport; |
1006 |
memcpy(net->udp_connections[con_id].outside_ip_address, |
1007 |
packet + 30, 4); |
1008 |
net->udp_connections[con_id].outside_udp_port = dstport; |
1009 |
|
1010 |
net->udp_connections[con_id].socket = socket(AF_INET, |
1011 |
SOCK_DGRAM, 0); |
1012 |
if (net->udp_connections[con_id].socket < 0) { |
1013 |
fatal("[ net: UDP: socket() returned %i ]\n", |
1014 |
net->udp_connections[con_id].socket); |
1015 |
return; |
1016 |
} |
1017 |
|
1018 |
debug(" {socket=%i}", net->udp_connections[con_id].socket); |
1019 |
|
1020 |
net->udp_connections[con_id].in_use = 1; |
1021 |
|
1022 |
/* Set the socket to non-blocking: */ |
1023 |
res = fcntl(net->udp_connections[con_id].socket, F_GETFL); |
1024 |
fcntl(net->udp_connections[con_id].socket, F_SETFL, |
1025 |
res | O_NONBLOCK); |
1026 |
} |
1027 |
|
1028 |
debug(", connection id %i\n", con_id); |
1029 |
|
1030 |
net->timestamp ++; |
1031 |
net->udp_connections[con_id].last_used_timestamp = net->timestamp; |
1032 |
|
1033 |
remote_ip.sin_family = AF_INET; |
1034 |
memcpy((unsigned char *)&remote_ip.sin_addr, |
1035 |
net->udp_connections[con_id].outside_ip_address, 4); |
1036 |
|
1037 |
/* |
1038 |
* Special case for the nameserver: If a UDP packet is sent to |
1039 |
* the gateway, it will be forwarded to the nameserver, if it is |
1040 |
* known. |
1041 |
*/ |
1042 |
if (net->nameserver_known && |
1043 |
memcmp(net->udp_connections[con_id].outside_ip_address, |
1044 |
&net->gateway_ipv4_addr[0], 4) == 0) { |
1045 |
memcpy((unsigned char *)&remote_ip.sin_addr, |
1046 |
&net->nameserver_ipv4, 4); |
1047 |
net->udp_connections[con_id].fake_ns = 1; |
1048 |
} |
1049 |
|
1050 |
remote_ip.sin_port = htons( |
1051 |
net->udp_connections[con_id].outside_udp_port); |
1052 |
|
1053 |
res = sendto(net->udp_connections[con_id].socket, packet + 42, |
1054 |
len - 42, 0, (const struct sockaddr *)&remote_ip, |
1055 |
sizeof(remote_ip)); |
1056 |
|
1057 |
if (res != len-42) |
1058 |
debug("[ net: UDP: unable to send %i bytes ]\n", len-42); |
1059 |
else |
1060 |
debug("[ net: UDP: OK!!! ]\n"); |
1061 |
} |
1062 |
|
1063 |
|
1064 |
/* |
1065 |
* net_ip(): |
1066 |
* |
1067 |
* Handle an IP packet, coming from the emulated NIC. |
1068 |
*/ |
1069 |
static void net_ip(struct net *net, void *extra, |
1070 |
unsigned char *packet, int len) |
1071 |
{ |
1072 |
#if 1 |
1073 |
int i; |
1074 |
|
1075 |
debug("[ net: IP: "); |
1076 |
debug("ver=%02x ", packet[14]); |
1077 |
debug("tos=%02x ", packet[15]); |
1078 |
debug("len=%02x%02x ", packet[16], packet[17]); |
1079 |
debug("id=%02x%02x ", packet[18], packet[19]); |
1080 |
debug("ofs=%02x%02x ", packet[20], packet[21]); |
1081 |
debug("ttl=%02x ", packet[22]); |
1082 |
debug("p=%02x ", packet[23]); |
1083 |
debug("sum=%02x%02x ", packet[24], packet[25]); |
1084 |
debug("src=%02x%02x%02x%02x ", |
1085 |
packet[26], packet[27], packet[28], packet[29]); |
1086 |
debug("dst=%02x%02x%02x%02x ", |
1087 |
packet[30], packet[31], packet[32], packet[33]); |
1088 |
for (i=34; i<len; i++) |
1089 |
debug("%02x", packet[i]); |
1090 |
debug(" ]\n"); |
1091 |
#endif |
1092 |
|
1093 |
/* Cut off overflowing tail data: */ |
1094 |
if (len > 14 + packet[16]*256 + packet[17]) |
1095 |
len = 14 + packet[16]*256 + packet[17]; |
1096 |
|
1097 |
if (packet[14] == 0x45) { |
1098 |
/* IPv4: */ |
1099 |
switch (packet[23]) { |
1100 |
case 1: /* ICMP */ |
1101 |
net_ip_icmp(net, extra, packet, len); |
1102 |
break; |
1103 |
case 6: /* TCP */ |
1104 |
net_ip_tcp(net, extra, packet, len); |
1105 |
break; |
1106 |
case 17:/* UDP */ |
1107 |
net_ip_udp(net, extra, packet, len); |
1108 |
break; |
1109 |
default: |
1110 |
fatal("[ net: IP: UNIMPLEMENTED protocol %i ]\n", |
1111 |
packet[23]); |
1112 |
} |
1113 |
} else |
1114 |
fatal("[ net: IP: UNIMPLEMENTED ip, first byte = 0x%02x ]\n", |
1115 |
packet[14]); |
1116 |
} |
1117 |
|
1118 |
|
1119 |
/* |
1120 |
* net_ip_broadcast_dhcp(): |
1121 |
* |
1122 |
* Handle an IPv4 DHCP broadcast packet, coming from the emulated NIC. |
1123 |
* |
1124 |
* Read http://www.ietf.org/rfc/rfc2131.txt for details on DHCP. |
1125 |
* (And http://users.telenet.be/mydotcom/library/network/dhcp.htm.) |
1126 |
*/ |
1127 |
static void net_ip_broadcast_dhcp(struct net *net, void *extra, |
1128 |
unsigned char *packet, int len) |
1129 |
{ |
1130 |
/* |
1131 |
* TODO |
1132 |
*/ |
1133 |
#if 0 |
1134 |
struct ethernet_packet_link *lp; |
1135 |
int i; |
1136 |
|
1137 |
fatal("[ net: IPv4 DHCP: "); |
1138 |
#if 0 |
1139 |
fatal("ver=%02x ", packet[14]); |
1140 |
fatal("tos=%02x ", packet[15]); |
1141 |
fatal("len=%02x%02x ", packet[16], packet[17]); |
1142 |
fatal("id=%02x%02x ", packet[18], packet[19]); |
1143 |
fatal("ofs=%02x%02x ", packet[20], packet[21]); |
1144 |
fatal("ttl=%02x ", packet[22]); |
1145 |
fatal("p=%02x ", packet[23]); |
1146 |
fatal("sum=%02x%02x ", packet[24], packet[25]); |
1147 |
#endif |
1148 |
fatal("src=%02x%02x%02x%02x ", |
1149 |
packet[26], packet[27], packet[28], packet[29]); |
1150 |
fatal("dst=%02x%02x%02x%02x ", |
1151 |
packet[30], packet[31], packet[32], packet[33]); |
1152 |
#if 0 |
1153 |
for (i=34; i<len; i++) |
1154 |
fatal("%02x", packet[i]); |
1155 |
#endif |
1156 |
|
1157 |
if (len < 34 + 8 + 236) { |
1158 |
fatal("[ DHCP packet too short? Len=%i ]\n", len); |
1159 |
return; |
1160 |
} |
1161 |
|
1162 |
/* |
1163 |
* UDP data (at offset 34): |
1164 |
* |
1165 |
* srcport=0044 dstport=0043 length=0134 chksum=a973 |
1166 |
* data = 01010600d116d276000000000000000000000000000000 |
1167 |
* 0000000000102030405060...0000...638253633501...000 |
1168 |
*/ |
1169 |
|
1170 |
fatal("op=%02x ", packet[42]); |
1171 |
fatal("htype=%02x ", packet[43]); |
1172 |
fatal("hlen=%02x ", packet[44]); |
1173 |
fatal("hops=%02x ", packet[45]); |
1174 |
fatal("xid=%02x%02x%02x%02x ", packet[46], packet[47], |
1175 |
packet[48], packet[49]); |
1176 |
fatal("secs=%02x%02x ", packet[50], packet[51]); |
1177 |
fatal("flags=%02x%02x ", packet[52], packet[53]); |
1178 |
fatal("ciaddr=%02x%02x%02x%02x ", packet[54], packet[55], |
1179 |
packet[56], packet[57]); |
1180 |
fatal("yiaddr=%02x%02x%02x%02x ", packet[58], packet[59], |
1181 |
packet[60], packet[61]); |
1182 |
fatal("siaddr=%02x%02x%02x%02x ", packet[62], packet[63], |
1183 |
packet[64], packet[65]); |
1184 |
fatal("giaddr=%02x%02x%02x%02x ", packet[66], packet[67], |
1185 |
packet[68], packet[69]); |
1186 |
fatal("chaddr="); |
1187 |
for (i=70; i<70+16; i++) |
1188 |
fatal("%02x", packet[i]); |
1189 |
/* |
1190 |
| sname (64) | |
1191 |
| file (128) | |
1192 |
*/ |
1193 |
fatal(" ]\n"); |
1194 |
|
1195 |
lp = net_allocate_packet_link(net, extra, len); |
1196 |
|
1197 |
/* Copy the old packet first: */ |
1198 |
memcpy(lp->data, packet, len); |
1199 |
|
1200 |
/* We are sending to the client, from the gateway: */ |
1201 |
memcpy(lp->data + 0, packet + 6, 6); |
1202 |
memcpy(lp->data + 6, net->gateway_ethernet_addr, 6); |
1203 |
|
1204 |
memcpy(lp->data + 26, &net->gateway_ipv4_addr[0], 4); |
1205 |
lp->data[30] = 0xff; |
1206 |
lp->data[31] = 0xff; |
1207 |
lp->data[32] = 0xff; |
1208 |
lp->data[33] = 0xff; |
1209 |
|
1210 |
/* Switch src and dst ports: */ |
1211 |
memcpy(lp->data + 34, packet + 36, 2); |
1212 |
memcpy(lp->data + 36, packet + 34, 2); |
1213 |
|
1214 |
/* Client's (yiaddr) IPv4 address: */ |
1215 |
lp->data[58] = 10; |
1216 |
lp->data[59] = 0; |
1217 |
lp->data[60] = 0; |
1218 |
lp->data[61] = 1; |
1219 |
|
1220 |
/* Server's IPv4 address: (giaddr) */ |
1221 |
memcpy(lp->data + 66, &net->gateway_ipv4_addr[0], 4); |
1222 |
|
1223 |
/* This is a Reply: */ |
1224 |
lp->data[42] = 0x02; |
1225 |
|
1226 |
sprintf(lp->data + 70+16+64, "gxemul"); |
1227 |
|
1228 |
/* Recalculate IP header checksum: */ |
1229 |
net_ip_checksum(lp->data + 14, 10, 20); |
1230 |
|
1231 |
/* ... and the UDP checksum: */ |
1232 |
net_ip_tcp_checksum(lp->data + 34, 6, len - 34 - 8, |
1233 |
lp->data + 26, lp->data + 30, 1); |
1234 |
|
1235 |
|
1236 |
/* Debug dump: */ |
1237 |
packet = lp->data; |
1238 |
fatal("[ net: IPv4 DHCP REPLY: "); |
1239 |
for (i=0; i<14; i++) |
1240 |
fatal("%02x", packet[i]); |
1241 |
fatal("ver=%02x ", packet[14]); |
1242 |
fatal("tos=%02x ", packet[15]); |
1243 |
fatal("len=%02x%02x ", packet[16], packet[17]); |
1244 |
fatal("id=%02x%02x ", packet[18], packet[19]); |
1245 |
fatal("ofs=%02x%02x ", packet[20], packet[21]); |
1246 |
fatal("ttl=%02x ", packet[22]); |
1247 |
fatal("p=%02x ", packet[23]); |
1248 |
fatal("sum=%02x%02x ", packet[24], packet[25]); |
1249 |
fatal("src=%02x%02x%02x%02x ", |
1250 |
packet[26], packet[27], packet[28], packet[29]); |
1251 |
fatal("dst=%02x%02x%02x%02x ", |
1252 |
packet[30], packet[31], packet[32], packet[33]); |
1253 |
fatal("op=%02x ", packet[42]); |
1254 |
fatal("htype=%02x ", packet[43]); |
1255 |
fatal("hlen=%02x ", packet[44]); |
1256 |
fatal("hops=%02x ", packet[45]); |
1257 |
fatal("xid=%02x%02x%02x%02x ", packet[46], packet[47], |
1258 |
packet[48], packet[49]); |
1259 |
fatal("secs=%02x%02x ", packet[50], packet[51]); |
1260 |
fatal("flags=%02x%02x ", packet[52], packet[53]); |
1261 |
fatal("ciaddr=%02x%02x%02x%02x ", packet[54], packet[55], |
1262 |
packet[56], packet[57]); |
1263 |
fatal("yiaddr=%02x%02x%02x%02x ", packet[58], packet[59], |
1264 |
packet[60], packet[61]); |
1265 |
fatal("siaddr=%02x%02x%02x%02x ", packet[62], packet[63], |
1266 |
packet[64], packet[65]); |
1267 |
fatal("giaddr=%02x%02x%02x%02x ", packet[66], packet[67], |
1268 |
packet[68], packet[69]); |
1269 |
fatal("chaddr="); |
1270 |
for (i=70; i<70+16; i++) |
1271 |
fatal("%02x", packet[i]); |
1272 |
fatal(" ]\n"); |
1273 |
|
1274 |
#endif |
1275 |
} |
1276 |
|
1277 |
|
1278 |
/* |
1279 |
* net_ip_broadcast(): |
1280 |
* |
1281 |
* Handle an IP broadcast packet, coming from the emulated NIC. |
1282 |
* (This is usually a DHCP request, or similar.) |
1283 |
*/ |
1284 |
static void net_ip_broadcast(struct net *net, void *extra, |
1285 |
unsigned char *packet, int len) |
1286 |
{ |
1287 |
unsigned char *p = (void *) &net->netmask_ipv4; |
1288 |
uint32_t x, y; |
1289 |
int i, xl, warning = 0, match = 0; |
1290 |
|
1291 |
#if 0 |
1292 |
fatal("[ net: IP BROADCAST: "); |
1293 |
fatal("ver=%02x ", packet[14]); |
1294 |
fatal("tos=%02x ", packet[15]); |
1295 |
fatal("len=%02x%02x ", packet[16], packet[17]); |
1296 |
fatal("id=%02x%02x ", packet[18], packet[19]); |
1297 |
fatal("ofs=%02x%02x ", packet[20], packet[21]); |
1298 |
fatal("ttl=%02x ", packet[22]); |
1299 |
fatal("p=%02x ", packet[23]); |
1300 |
fatal("sum=%02x%02x ", packet[24], packet[25]); |
1301 |
fatal("src=%02x%02x%02x%02x ", |
1302 |
packet[26], packet[27], packet[28], packet[29]); |
1303 |
fatal("dst=%02x%02x%02x%02x ", |
1304 |
packet[30], packet[31], packet[32], packet[33]); |
1305 |
for (i=34; i<len; i++) |
1306 |
fatal("%02x", packet[i]); |
1307 |
fatal(" ]\n"); |
1308 |
#endif |
1309 |
|
1310 |
/* Check for 10.0.0.255 first, maybe some guest OSes think that |
1311 |
it's a /24 network, regardless of what it actually is. */ |
1312 |
y = (packet[30] << 24) + (packet[31] << 16) + |
1313 |
(packet[32] << 8) + packet[33]; |
1314 |
|
1315 |
x = (p[0] << 24) + (p[1] << 16) + (p[2] << 8) + p[3]; |
1316 |
/* Example: x = 10.0.0.0 */ |
1317 |
x |= 255; |
1318 |
|
1319 |
if (x == y) { |
1320 |
warning = 1; |
1321 |
match = 1; |
1322 |
} |
1323 |
|
1324 |
xl = 32 - net->netmask_ipv4_len; |
1325 |
x |= (1 << xl) - 1; |
1326 |
/* x = 10.255.255.255 */ |
1327 |
|
1328 |
if (x == y) |
1329 |
match = 1; |
1330 |
if (y == 0xffffffff) |
1331 |
match = 1; |
1332 |
|
1333 |
if (warning) |
1334 |
fatal("[ net_ip_broadcast(): warning: broadcast to " |
1335 |
"0x%08x, expecting broadcast to 0x%08x or " |
1336 |
"0xffffffff ]\n", y, x); |
1337 |
|
1338 |
/* Cut off overflowing tail data: */ |
1339 |
if (len > 14 + packet[16]*256 + packet[17]) |
1340 |
len = 14 + packet[16]*256 + packet[17]; |
1341 |
|
1342 |
/* Check for known packets: */ |
1343 |
if (packet[14] == 0x45 && /* IPv4 */ |
1344 |
packet[23] == 0x11 && /* UDP */ |
1345 |
packet[34] == 0 && packet[35] == 68 && /* DHCP client */ |
1346 |
packet[36] == 0 && packet[37] == 67) { /* DHCP server */ |
1347 |
net_ip_broadcast_dhcp(net, extra, packet, len); |
1348 |
return; |
1349 |
} |
1350 |
|
1351 |
/* Unknown packet: */ |
1352 |
fatal("[ net: UNIMPLEMENTED IP BROADCAST: "); |
1353 |
fatal("ver=%02x ", packet[14]); |
1354 |
fatal("tos=%02x ", packet[15]); |
1355 |
fatal("len=%02x%02x ", packet[16], packet[17]); |
1356 |
fatal("id=%02x%02x ", packet[18], packet[19]); |
1357 |
fatal("ofs=%02x%02x ", packet[20], packet[21]); |
1358 |
fatal("ttl=%02x ", packet[22]); |
1359 |
fatal("p=%02x ", packet[23]); |
1360 |
fatal("sum=%02x%02x ", packet[24], packet[25]); |
1361 |
fatal("src=%02x%02x%02x%02x ", |
1362 |
packet[26], packet[27], packet[28], packet[29]); |
1363 |
fatal("dst=%02x%02x%02x%02x ", |
1364 |
packet[30], packet[31], packet[32], packet[33]); |
1365 |
for (i=34; i<len; i++) |
1366 |
fatal("%02x", packet[i]); |
1367 |
fatal(" ]\n"); |
1368 |
} |
1369 |
|
1370 |
|
1371 |
/* |
1372 |
* net_arp(): |
1373 |
* |
1374 |
* Handle an ARP (or RARP) packet, coming from the emulated NIC. |
1375 |
* |
1376 |
* An ARP packet might look like this: |
1377 |
* |
1378 |
* ARP header: |
1379 |
* ARP hardware addr family: 0001 |
1380 |
* ARP protocol addr family: 0800 |
1381 |
* ARP addr lengths: 06 04 |
1382 |
* ARP request: 0001 |
1383 |
* ARP from: 112233445566 01020304 |
1384 |
* ARP to: 000000000000 01020301 |
1385 |
* |
1386 |
* An ARP request with a 'to' IP value of the gateway should cause an |
1387 |
* ARP response packet to be created. |
1388 |
* |
1389 |
* An ARP request with the same from and to IP addresses should be ignored. |
1390 |
* (This would be a host testing to see if there is an IP collision.) |
1391 |
*/ |
1392 |
static void net_arp(struct net *net, void *extra, |
1393 |
unsigned char *packet, int len, int reverse) |
1394 |
{ |
1395 |
int q; |
1396 |
int i; |
1397 |
|
1398 |
/* TODO: This debug dump assumes ethernet->IPv4 translation: */ |
1399 |
if (reverse) |
1400 |
debug("[ net: RARP: "); |
1401 |
else |
1402 |
debug("[ net: ARP: "); |
1403 |
for (i=0; i<2; i++) |
1404 |
debug("%02x", packet[i]); |
1405 |
debug(" "); |
1406 |
for (i=2; i<4; i++) |
1407 |
debug("%02x", packet[i]); |
1408 |
debug(" "); |
1409 |
debug("%02x", packet[4]); |
1410 |
debug(" "); |
1411 |
debug("%02x", packet[5]); |
1412 |
debug(" req="); |
1413 |
debug("%02x", packet[6]); /* Request type */ |
1414 |
debug("%02x", packet[7]); |
1415 |
debug(" from="); |
1416 |
for (i=8; i<18; i++) |
1417 |
debug("%02x", packet[i]); |
1418 |
debug(" to="); |
1419 |
for (i=18; i<28; i++) |
1420 |
debug("%02x", packet[i]); |
1421 |
debug(" ]\n"); |
1422 |
|
1423 |
if (packet[0] == 0x00 && packet[1] == 0x01 && |
1424 |
packet[2] == 0x08 && packet[3] == 0x00 && |
1425 |
packet[4] == 0x06 && packet[5] == 0x04) { |
1426 |
int r = (packet[6] << 8) + packet[7]; |
1427 |
struct ethernet_packet_link *lp; |
1428 |
|
1429 |
switch (r) { |
1430 |
case 1: /* Request */ |
1431 |
/* Only create a reply if this was meant for the |
1432 |
gateway: */ |
1433 |
if (memcmp(packet+24, net->gateway_ipv4_addr, 4) != 0) |
1434 |
break; |
1435 |
|
1436 |
lp = net_allocate_packet_link(net, extra, len + 14); |
1437 |
|
1438 |
/* Copy the old packet first: */ |
1439 |
memcpy(lp->data + 14, packet, len); |
1440 |
|
1441 |
/* Add ethernet ARP header: */ |
1442 |
memcpy(lp->data + 0, lp->data + 8 + 14, 6); |
1443 |
memcpy(lp->data + 6, net->gateway_ethernet_addr, 6); |
1444 |
lp->data[12] = 0x08; lp->data[13] = 0x06; |
1445 |
|
1446 |
/* Address of the emulated machine: */ |
1447 |
memcpy(lp->data + 18 + 14, lp->data + 8 + 14, 10); |
1448 |
|
1449 |
/* Address of the gateway: */ |
1450 |
memcpy(lp->data + 8 + 14, net->gateway_ethernet_addr, |
1451 |
6); |
1452 |
memcpy(lp->data + 14 + 14, net->gateway_ipv4_addr, 4); |
1453 |
|
1454 |
/* This is a Reply: */ |
1455 |
lp->data[6 + 14] = 0x00; lp->data[7 + 14] = 0x02; |
1456 |
|
1457 |
break; |
1458 |
case 3: /* Reverse Request */ |
1459 |
lp = net_allocate_packet_link(net, extra, len + 14); |
1460 |
|
1461 |
/* Copy the old packet first: */ |
1462 |
memcpy(lp->data + 14, packet, len); |
1463 |
|
1464 |
/* Add ethernet RARP header: */ |
1465 |
memcpy(lp->data + 0, packet + 8, 6); |
1466 |
memcpy(lp->data + 6, net->gateway_ethernet_addr, 6); |
1467 |
lp->data[12] = 0x80; lp->data[13] = 0x35; |
1468 |
|
1469 |
/* This is a RARP reply: */ |
1470 |
lp->data[6 + 14] = 0x00; lp->data[7 + 14] = 0x04; |
1471 |
|
1472 |
/* Address of the gateway: */ |
1473 |
memcpy(lp->data + 8 + 14, net->gateway_ethernet_addr, |
1474 |
6); |
1475 |
memcpy(lp->data + 14 + 14, net->gateway_ipv4_addr, 4); |
1476 |
|
1477 |
/* MAC address of emulated machine: */ |
1478 |
memcpy(lp->data + 18 + 14, packet + 8, 6); |
1479 |
|
1480 |
/* |
1481 |
* IP address of the emulated machine: Automagically |
1482 |
* generated from the MAC address. :-) |
1483 |
* |
1484 |
* packet+8 points to the client's mac address, |
1485 |
* for example 10:20:30:x0:y0:z0, where x,y,z are |
1486 |
* 1..15. |
1487 |
* 10:20:30:10:10:10 results in 10.0.0.1. |
1488 |
*/ |
1489 |
q = (((packet[8 + 3]) >> 4) - 1); |
1490 |
q = q*15 + (((packet[8 + 4]) >> 4) - 1); |
1491 |
q = q*15 + (((packet[8 + 5]) >> 4) - 1); |
1492 |
lp->data[24 + 14] = 10; |
1493 |
lp->data[25 + 14] = q / 225; q /= 15; |
1494 |
lp->data[26 + 14] = q / 15; q /= 15; |
1495 |
lp->data[27 + 14] = q + 1; |
1496 |
|
1497 |
break; |
1498 |
case 2: /* Reply */ |
1499 |
case 4: /* Reverse Reply */ |
1500 |
default: |
1501 |
fatal("[ net: ARP: UNIMPLEMENTED request type " |
1502 |
"0x%04x ]\n", r); |
1503 |
} |
1504 |
} else { |
1505 |
fatal("[ net: ARP: UNIMPLEMENTED arp packet type: "); |
1506 |
for (i=0; i<len; i++) |
1507 |
fatal("%02x", packet[i]); |
1508 |
fatal(" ]\n"); |
1509 |
} |
1510 |
} |
1511 |
|
1512 |
|
1513 |
/* |
1514 |
* net_ethernet_rx_avail(): |
1515 |
* |
1516 |
* Return 1 if there is a packet available for this 'extra' pointer, otherwise |
1517 |
* return 0. |
1518 |
* |
1519 |
* Appart from actually checking for incoming packets from the outside world, |
1520 |
* this function basically works like net_ethernet_rx() but it only receives |
1521 |
* a return value telling us whether there is a packet or not, we don't |
1522 |
* actually get the packet. |
1523 |
*/ |
1524 |
int net_ethernet_rx_avail(struct net *net, void *extra) |
1525 |
{ |
1526 |
int received_packets_this_tick = 0; |
1527 |
int max_packets_this_tick = 200; |
1528 |
int con_id; |
1529 |
|
1530 |
if (net == NULL) |
1531 |
return 0; |
1532 |
|
1533 |
/* |
1534 |
* UDP: |
1535 |
*/ |
1536 |
for (con_id=0; con_id<MAX_UDP_CONNECTIONS; con_id++) { |
1537 |
ssize_t res; |
1538 |
unsigned char buf[66000]; |
1539 |
unsigned char udp_data[66008]; |
1540 |
struct sockaddr_in from; |
1541 |
socklen_t from_len = sizeof(from); |
1542 |
int ip_len, udp_len; |
1543 |
struct ethernet_packet_link *lp; |
1544 |
int max_per_packet; |
1545 |
int bytes_converted = 0; |
1546 |
int this_packets_data_length; |
1547 |
int fragment_ofs = 0; |
1548 |
|
1549 |
if (received_packets_this_tick > max_packets_this_tick) |
1550 |
break; |
1551 |
|
1552 |
if (!net->udp_connections[con_id].in_use) |
1553 |
continue; |
1554 |
|
1555 |
if (net->udp_connections[con_id].socket < 0) { |
1556 |
fatal("INTERNAL ERROR in net.c, udp socket < 0 " |
1557 |
"but in use?\n"); |
1558 |
continue; |
1559 |
} |
1560 |
|
1561 |
res = recvfrom(net->udp_connections[con_id].socket, buf, |
1562 |
sizeof(buf), 0, (struct sockaddr *)&from, &from_len); |
1563 |
|
1564 |
/* No more incoming UDP on this connection? */ |
1565 |
if (res < 0) |
1566 |
continue; |
1567 |
|
1568 |
net->timestamp ++; |
1569 |
net->udp_connections[con_id].last_used_timestamp = |
1570 |
net->timestamp; |
1571 |
|
1572 |
net->udp_connections[con_id].udp_id ++; |
1573 |
|
1574 |
/* |
1575 |
* Special case for the nameserver: If a UDP packet is |
1576 |
* received from the nameserver (if the nameserver's IP is |
1577 |
* known), fake it so that it comes from the gateway instead. |
1578 |
*/ |
1579 |
if (net->udp_connections[con_id].fake_ns) |
1580 |
memcpy(((unsigned char *)(&from))+4, |
1581 |
&net->gateway_ipv4_addr[0], 4); |
1582 |
|
1583 |
/* |
1584 |
* We now have a UDP packet of size 'res' which we need |
1585 |
* turn into one or more ethernet packets for the emulated |
1586 |
* operating system. Ethernet packets are at most 1518 |
1587 |
* bytes long. With some margin, that means we can have |
1588 |
* about 1500 bytes per packet. |
1589 |
* |
1590 |
* Ethernet = 14 bytes |
1591 |
* IP = 20 bytes |
1592 |
* (UDP = 8 bytes + data) |
1593 |
* |
1594 |
* So data can be at most max_per_packet - 34. For UDP |
1595 |
* fragments, each multiple should (?) be a multiple of |
1596 |
* 8 bytes, except the last which doesn't have any such |
1597 |
* restriction. |
1598 |
*/ |
1599 |
max_per_packet = 1500; |
1600 |
|
1601 |
/* UDP: */ |
1602 |
udp_len = res + 8; |
1603 |
/* from[2..3] = outside_udp_port */ |
1604 |
udp_data[0] = ((unsigned char *)&from)[2]; |
1605 |
udp_data[1] = ((unsigned char *)&from)[3]; |
1606 |
udp_data[2] = (net->udp_connections[con_id]. |
1607 |
inside_udp_port >> 8) & 0xff; |
1608 |
udp_data[3] = net->udp_connections[con_id]. |
1609 |
inside_udp_port & 0xff; |
1610 |
udp_data[4] = udp_len >> 8; |
1611 |
udp_data[5] = udp_len & 0xff; |
1612 |
udp_data[6] = 0; |
1613 |
udp_data[7] = 0; |
1614 |
memcpy(udp_data + 8, buf, res); |
1615 |
/* |
1616 |
* TODO: UDP checksum, if necessary. At least NetBSD |
1617 |
* and OpenBSD accept UDP packets with 0x0000 in the |
1618 |
* checksum field anyway. |
1619 |
*/ |
1620 |
|
1621 |
while (bytes_converted < udp_len) { |
1622 |
this_packets_data_length = udp_len - bytes_converted; |
1623 |
|
1624 |
/* Do we need to fragment? */ |
1625 |
if (this_packets_data_length > max_per_packet-34) { |
1626 |
this_packets_data_length = |
1627 |
max_per_packet - 34; |
1628 |
while (this_packets_data_length & 7) |
1629 |
this_packets_data_length --; |
1630 |
} |
1631 |
|
1632 |
ip_len = 20 + this_packets_data_length; |
1633 |
|
1634 |
lp = net_allocate_packet_link(net, extra, |
1635 |
14 + 20 + this_packets_data_length); |
1636 |
|
1637 |
/* Ethernet header: */ |
1638 |
memcpy(lp->data + 0, net->udp_connections[con_id]. |
1639 |
ethernet_address, 6); |
1640 |
memcpy(lp->data + 6, net->gateway_ethernet_addr, 6); |
1641 |
lp->data[12] = 0x08; /* IP = 0x0800 */ |
1642 |
lp->data[13] = 0x00; |
1643 |
|
1644 |
/* IP header: */ |
1645 |
lp->data[14] = 0x45; /* ver */ |
1646 |
lp->data[15] = 0x00; /* tos */ |
1647 |
lp->data[16] = ip_len >> 8; |
1648 |
lp->data[17] = ip_len & 0xff; |
1649 |
lp->data[18] = net->udp_connections[con_id].udp_id >> 8; |
1650 |
lp->data[19] = net->udp_connections[con_id].udp_id |
1651 |
& 0xff; |
1652 |
lp->data[20] = (fragment_ofs >> 8); |
1653 |
if (bytes_converted + this_packets_data_length |
1654 |
< udp_len) |
1655 |
lp->data[20] |= 0x20; /* More fragments */ |
1656 |
lp->data[21] = fragment_ofs & 0xff; |
1657 |
lp->data[22] = 0x40; /* ttl */ |
1658 |
lp->data[23] = 17; /* p = UDP */ |
1659 |
lp->data[26] = ((unsigned char *)&from)[4]; |
1660 |
lp->data[27] = ((unsigned char *)&from)[5]; |
1661 |
lp->data[28] = ((unsigned char *)&from)[6]; |
1662 |
lp->data[29] = ((unsigned char *)&from)[7]; |
1663 |
memcpy(lp->data + 30, net->udp_connections[con_id]. |
1664 |
inside_ip_address, 4); |
1665 |
net_ip_checksum(lp->data + 14, 10, 20); |
1666 |
|
1667 |
memcpy(lp->data+34, udp_data + bytes_converted, |
1668 |
this_packets_data_length); |
1669 |
|
1670 |
bytes_converted += this_packets_data_length; |
1671 |
fragment_ofs = bytes_converted / 8; |
1672 |
|
1673 |
received_packets_this_tick ++; |
1674 |
} |
1675 |
|
1676 |
/* This makes sure we check this connection AGAIN |
1677 |
for more incoming UDP packets, before moving to the |
1678 |
next connection: */ |
1679 |
con_id --; |
1680 |
} |
1681 |
|
1682 |
/* |
1683 |
* TCP: |
1684 |
*/ |
1685 |
for (con_id=0; con_id<MAX_TCP_CONNECTIONS; con_id++) { |
1686 |
unsigned char buf[66000]; |
1687 |
ssize_t res, res2; |
1688 |
fd_set rfds; |
1689 |
struct timeval tv; |
1690 |
|
1691 |
if (received_packets_this_tick > max_packets_this_tick) |
1692 |
break; |
1693 |
|
1694 |
if (!net->tcp_connections[con_id].in_use) |
1695 |
continue; |
1696 |
|
1697 |
if (net->tcp_connections[con_id].socket < 0) { |
1698 |
fatal("INTERNAL ERROR in net.c, tcp socket < 0" |
1699 |
" but in use?\n"); |
1700 |
continue; |
1701 |
} |
1702 |
|
1703 |
if (net->tcp_connections[con_id].incoming_buf == NULL) { |
1704 |
net->tcp_connections[con_id].incoming_buf = |
1705 |
malloc(TCP_INCOMING_BUF_LEN); |
1706 |
if (net->tcp_connections[con_id].incoming_buf == NULL) { |
1707 |
printf("out of memory allocating " |
1708 |
"incoming_buf for con_id %i\n", con_id); |
1709 |
exit(1); |
1710 |
} |
1711 |
} |
1712 |
|
1713 |
if (net->tcp_connections[con_id].state >= |
1714 |
TCP_OUTSIDE_DISCONNECTED) |
1715 |
continue; |
1716 |
|
1717 |
/* Is the socket available for output? */ |
1718 |
FD_ZERO(&rfds); /* write */ |
1719 |
FD_SET(net->tcp_connections[con_id].socket, &rfds); |
1720 |
tv.tv_sec = tv.tv_usec = 0; |
1721 |
errno = 0; |
1722 |
res = select(net->tcp_connections[con_id].socket+1, |
1723 |
NULL, &rfds, NULL, &tv); |
1724 |
|
1725 |
if (errno == ECONNREFUSED) { |
1726 |
fatal("[ ECONNREFUSED: TODO ]\n"); |
1727 |
net->tcp_connections[con_id].state = |
1728 |
TCP_OUTSIDE_DISCONNECTED; |
1729 |
fatal("CHANGING TO TCP_OUTSIDE_DISCONNECTED " |
1730 |
"(refused connection)\n"); |
1731 |
continue; |
1732 |
} |
1733 |
|
1734 |
if (errno == ETIMEDOUT) { |
1735 |
fatal("[ ETIMEDOUT: TODO ]\n"); |
1736 |
/* TODO */ |
1737 |
net->tcp_connections[con_id].state = |
1738 |
TCP_OUTSIDE_DISCONNECTED; |
1739 |
fatal("CHANGING TO TCP_OUTSIDE_DISCONNECTED " |
1740 |
"(timeout)\n"); |
1741 |
continue; |
1742 |
} |
1743 |
|
1744 |
if (net->tcp_connections[con_id].state == |
1745 |
TCP_OUTSIDE_TRYINGTOCONNECT && res > 0) { |
1746 |
net->tcp_connections[con_id].state = |
1747 |
TCP_OUTSIDE_CONNECTED; |
1748 |
debug("CHANGING TO TCP_OUTSIDE_CONNECTED\n"); |
1749 |
net_ip_tcp_connectionreply(net, extra, con_id, 1, |
1750 |
NULL, 0, 0); |
1751 |
} |
1752 |
|
1753 |
if (net->tcp_connections[con_id].state == |
1754 |
TCP_OUTSIDE_CONNECTED && res < 1) { |
1755 |
continue; |
1756 |
} |
1757 |
|
1758 |
/* |
1759 |
* Does this connection have unacknowledged data? Then, if |
1760 |
* enough number of rounds have passed, try to resend it using |
1761 |
* the old value of seqnr. |
1762 |
*/ |
1763 |
if (net->tcp_connections[con_id].incoming_buf_len != 0) { |
1764 |
net->tcp_connections[con_id].incoming_buf_rounds ++; |
1765 |
if (net->tcp_connections[con_id].incoming_buf_rounds > |
1766 |
10000) { |
1767 |
debug(" at seqnr %u but backing back to %u," |
1768 |
" resending %i bytes\n", |
1769 |
net->tcp_connections[con_id].outside_seqnr, |
1770 |
net->tcp_connections[con_id]. |
1771 |
incoming_buf_seqnr, |
1772 |
net->tcp_connections[con_id]. |
1773 |
incoming_buf_len); |
1774 |
|
1775 |
net->tcp_connections[con_id]. |
1776 |
incoming_buf_rounds = 0; |
1777 |
net->tcp_connections[con_id].outside_seqnr = |
1778 |
net->tcp_connections[con_id]. |
1779 |
incoming_buf_seqnr; |
1780 |
|
1781 |
net_ip_tcp_connectionreply(net, extra, con_id, |
1782 |
0, net->tcp_connections[con_id]. |
1783 |
incoming_buf, |
1784 |
net->tcp_connections[con_id]. |
1785 |
incoming_buf_len, 0); |
1786 |
} |
1787 |
continue; |
1788 |
} |
1789 |
|
1790 |
/* Don't receive unless the guest OS is ready! */ |
1791 |
if (((int32_t)net->tcp_connections[con_id].outside_seqnr - |
1792 |
(int32_t)net->tcp_connections[con_id].inside_acknr) > 0) { |
1793 |
/* fatal("YOYO 1! outside_seqnr - inside_acknr = %i\n", |
1794 |
net->tcp_connections[con_id].outside_seqnr - |
1795 |
net->tcp_connections[con_id].inside_acknr); */ |
1796 |
continue; |
1797 |
} |
1798 |
|
1799 |
/* Is there incoming data available on the socket? */ |
1800 |
FD_ZERO(&rfds); /* read */ |
1801 |
FD_SET(net->tcp_connections[con_id].socket, &rfds); |
1802 |
tv.tv_sec = tv.tv_usec = 0; |
1803 |
res2 = select(net->tcp_connections[con_id].socket+1, &rfds, |
1804 |
NULL, NULL, &tv); |
1805 |
|
1806 |
/* No more incoming TCP data on this connection? */ |
1807 |
if (res2 < 1) |
1808 |
continue; |
1809 |
|
1810 |
res = read(net->tcp_connections[con_id].socket, buf, 1400); |
1811 |
if (res > 0) { |
1812 |
/* debug("\n -{- %lli -}-\n", (long long)res); */ |
1813 |
net->tcp_connections[con_id].incoming_buf_len = res; |
1814 |
net->tcp_connections[con_id].incoming_buf_rounds = 0; |
1815 |
net->tcp_connections[con_id].incoming_buf_seqnr = |
1816 |
net->tcp_connections[con_id].outside_seqnr; |
1817 |
debug(" putting %i bytes (seqnr %u) in the incoming " |
1818 |
"buf\n", res, net->tcp_connections[con_id]. |
1819 |
incoming_buf_seqnr); |
1820 |
memcpy(net->tcp_connections[con_id].incoming_buf, |
1821 |
buf, res); |
1822 |
|
1823 |
net_ip_tcp_connectionreply(net, extra, con_id, 0, |
1824 |
buf, res, 0); |
1825 |
} else if (res == 0) { |
1826 |
net->tcp_connections[con_id].state = |
1827 |
TCP_OUTSIDE_DISCONNECTED; |
1828 |
debug("CHANGING TO TCP_OUTSIDE_DISCONNECTED, read" |
1829 |
" res=0\n"); |
1830 |
net_ip_tcp_connectionreply(net, extra, con_id, 0, |
1831 |
NULL, 0, 0); |
1832 |
} else { |
1833 |
net->tcp_connections[con_id].state = |
1834 |
TCP_OUTSIDE_DISCONNECTED; |
1835 |
fatal("CHANGING TO TCP_OUTSIDE_DISCONNECTED, " |
1836 |
"read res<=0, errno = %i\n", errno); |
1837 |
net_ip_tcp_connectionreply(net, extra, con_id, 0, |
1838 |
NULL, 0, 0); |
1839 |
} |
1840 |
|
1841 |
net->timestamp ++; |
1842 |
net->tcp_connections[con_id].last_used_timestamp = |
1843 |
net->timestamp; |
1844 |
} |
1845 |
|
1846 |
return net_ethernet_rx(net, extra, NULL, NULL); |
1847 |
} |
1848 |
|
1849 |
|
1850 |
/* |
1851 |
* net_ethernet_rx(): |
1852 |
* |
1853 |
* Receive an ethernet packet. (This means handing over an already prepared |
1854 |
* packet from this module (net.c) to a specific ethernet controller device.) |
1855 |
* |
1856 |
* Return value is 1 if there was a packet available. *packetp and *lenp |
1857 |
* will be set to the packet's data pointer and length, respectively, and |
1858 |
* the packet will be removed from the linked list). If there was no packet |
1859 |
* available, 0 is returned. |
1860 |
* |
1861 |
* If packetp is NULL, then the search is aborted as soon as a packet with |
1862 |
* the correct 'extra' field is found, and a 1 is returned, but as packetp |
1863 |
* is NULL we can't return the actual packet. (This is the internal form |
1864 |
* if net_ethernet_rx_avail().) |
1865 |
*/ |
1866 |
int net_ethernet_rx(struct net *net, void *extra, |
1867 |
unsigned char **packetp, int *lenp) |
1868 |
{ |
1869 |
struct ethernet_packet_link *lp, *prev; |
1870 |
|
1871 |
if (net == NULL) |
1872 |
return 0; |
1873 |
|
1874 |
/* Find the first packet which has the right 'extra' field. */ |
1875 |
|
1876 |
lp = net->first_ethernet_packet; |
1877 |
prev = NULL; |
1878 |
while (lp != NULL) { |
1879 |
if (lp->extra == extra) { |
1880 |
/* We found a packet for this controller! */ |
1881 |
if (packetp == NULL || lenp == NULL) |
1882 |
return 1; |
1883 |
|
1884 |
/* Let's return it: */ |
1885 |
(*packetp) = lp->data; |
1886 |
(*lenp) = lp->len; |
1887 |
|
1888 |
/* Remove this link from the linked list: */ |
1889 |
if (prev == NULL) |
1890 |
net->first_ethernet_packet = lp->next; |
1891 |
else |
1892 |
prev->next = lp->next; |
1893 |
|
1894 |
if (lp->next == NULL) |
1895 |
net->last_ethernet_packet = prev; |
1896 |
else |
1897 |
lp->next->prev = prev; |
1898 |
|
1899 |
free(lp); |
1900 |
|
1901 |
/* ... and return successfully: */ |
1902 |
return 1; |
1903 |
} |
1904 |
|
1905 |
prev = lp; |
1906 |
lp = lp->next; |
1907 |
} |
1908 |
|
1909 |
/* No packet found. :-( */ |
1910 |
return 0; |
1911 |
} |
1912 |
|
1913 |
|
1914 |
/* |
1915 |
* net_ethernet_tx(): |
1916 |
* |
1917 |
* Transmit an ethernet packet, as seen from the emulated ethernet controller. |
1918 |
* If the packet can be handled here, it will not necessarily be transmitted |
1919 |
* to the outside world. |
1920 |
*/ |
1921 |
void net_ethernet_tx(struct net *net, void *extra, |
1922 |
unsigned char *packet, int len) |
1923 |
{ |
1924 |
int i, n; |
1925 |
|
1926 |
if (net == NULL) |
1927 |
return; |
1928 |
|
1929 |
/* Drop too small packets: */ |
1930 |
if (len < 20) |
1931 |
return; |
1932 |
|
1933 |
/* Copy this packet to all other NICs on this network: */ |
1934 |
if (extra != NULL && net->n_nics > 0) { |
1935 |
for (i=0; i<net->n_nics; i++) |
1936 |
if (extra != net->nic_extra[i]) { |
1937 |
struct ethernet_packet_link *lp; |
1938 |
lp = net_allocate_packet_link(net, |
1939 |
net->nic_extra[i], len); |
1940 |
|
1941 |
/* Copy the entire packet: */ |
1942 |
memcpy(lp->data, packet, len); |
1943 |
} |
1944 |
} |
1945 |
|
1946 |
/* Drop packets that are not destined for the gateway: */ |
1947 |
if (memcmp(packet, net->gateway_ethernet_addr, 6) != 0 |
1948 |
&& packet[0] != 0xff && packet[0] != 0x00) |
1949 |
return; |
1950 |
|
1951 |
#if 0 |
1952 |
fatal("[ net: ethernet: "); |
1953 |
for (i=0; i<6; i++) |
1954 |
fatal("%02x", packet[i]); |
1955 |
fatal(" "); |
1956 |
for (i=6; i<12; i++) |
1957 |
fatal("%02x", packet[i]); |
1958 |
fatal(" "); |
1959 |
for (i=12; i<14; i++) |
1960 |
fatal("%02x", packet[i]); |
1961 |
fatal(" "); |
1962 |
for (i=14; i<len; i++) |
1963 |
fatal("%02x", packet[i]); |
1964 |
fatal(" ]\n"); |
1965 |
#endif |
1966 |
|
1967 |
/* Sprite: */ |
1968 |
if (packet[12] == 0x05 && packet[13] == 0x00) { |
1969 |
/* TODO. */ |
1970 |
fatal("[ net: TX: UNIMPLEMENTED Sprite packet ]\n"); |
1971 |
return; |
1972 |
} |
1973 |
|
1974 |
/* IP: */ |
1975 |
if (packet[12] == 0x08 && packet[13] == 0x00) { |
1976 |
/* Routed via the gateway? */ |
1977 |
if (memcmp(packet+0, net->gateway_ethernet_addr, 6) == 0) { |
1978 |
net_ip(net, extra, packet, len); |
1979 |
return; |
1980 |
} |
1981 |
|
1982 |
/* Broadcast? (DHCP does this.) */ |
1983 |
n = 0; |
1984 |
for (i=0; i<6; i++) |
1985 |
if (packet[i] == 0xff) |
1986 |
n++; |
1987 |
if (n == 6) { |
1988 |
net_ip_broadcast(net, extra, packet, len); |
1989 |
return; |
1990 |
} |
1991 |
|
1992 |
if (net->n_nics < 2) { |
1993 |
fatal("[ net: TX: IP packet not for gateway, " |
1994 |
"and not broadcast: "); |
1995 |
for (i=0; i<14; i++) |
1996 |
fatal("%02x", packet[i]); |
1997 |
fatal(" ]\n"); |
1998 |
} |
1999 |
return; |
2000 |
} |
2001 |
|
2002 |
/* ARP: */ |
2003 |
if (packet[12] == 0x08 && packet[13] == 0x06) { |
2004 |
if (len != 60) |
2005 |
fatal("[ net_ethernet_tx: WARNING! unusual " |
2006 |
"ARP len (%i) ]\n", len); |
2007 |
net_arp(net, extra, packet + 14, len - 14, 0); |
2008 |
return; |
2009 |
} |
2010 |
|
2011 |
/* RARP: */ |
2012 |
if (packet[12] == 0x80 && packet[13] == 0x35) { |
2013 |
net_arp(net, extra, packet + 14, len - 14, 1); |
2014 |
return; |
2015 |
} |
2016 |
|
2017 |
/* IPv6: */ |
2018 |
if (packet[12] == 0x86 && packet[13] == 0xdd) { |
2019 |
/* TODO. */ |
2020 |
fatal("[ net: TX: UNIMPLEMENTED IPv6 packet ]\n"); |
2021 |
return; |
2022 |
} |
2023 |
|
2024 |
fatal("[ net: TX: UNIMPLEMENTED ethernet packet type 0x%02x%02x! ]\n", |
2025 |
packet[12], packet[13]); |
2026 |
} |
2027 |
|
2028 |
|
2029 |
/* |
2030 |
* parse_resolvconf(): |
2031 |
* |
2032 |
* This function parses "/etc/resolv.conf" to figure out the nameserver |
2033 |
* and domain used by the host. |
2034 |
*/ |
2035 |
static void parse_resolvconf(struct net *net) |
2036 |
{ |
2037 |
FILE *f; |
2038 |
char buf[8000]; |
2039 |
size_t len; |
2040 |
int res; |
2041 |
unsigned int i, start; |
2042 |
|
2043 |
/* |
2044 |
* This is a very ugly hack, which tries to figure out which |
2045 |
* nameserver the host uses by looking for the string 'nameserver' |
2046 |
* in /etc/resolv.conf. |
2047 |
* |
2048 |
* This can later on be used for DHCP autoconfiguration. (TODO) |
2049 |
* |
2050 |
* TODO: This is hardcoded to use /etc/resolv.conf. Not all |
2051 |
* operating systems use that filename. |
2052 |
* |
2053 |
* TODO: This is hardcoded for AF_INET (that is, IPv4). |
2054 |
* |
2055 |
* TODO: This assumes that the first nameserver listed is the |
2056 |
* one to use. |
2057 |
*/ |
2058 |
f = fopen("/etc/resolv.conf", "r"); |
2059 |
if (f == NULL) |
2060 |
return; |
2061 |
|
2062 |
/* TODO: get rid of the hardcoded values */ |
2063 |
memset(buf, 0, sizeof(buf)); |
2064 |
len = fread(buf, 1, sizeof(buf) - 100, f); |
2065 |
fclose(f); |
2066 |
buf[sizeof(buf) - 1] = '\0'; |
2067 |
|
2068 |
for (i=0; i<len; i++) |
2069 |
if (strncmp(buf+i, "nameserver", 10) == 0) { |
2070 |
char *p; |
2071 |
|
2072 |
/* |
2073 |
* "nameserver" (1 or more whitespace) |
2074 |
* "x.y.z.w" (non-digit) |
2075 |
*/ |
2076 |
|
2077 |
/* debug("found nameserver at offset %i\n", i); */ |
2078 |
i += 10; |
2079 |
while (i<len && (buf[i]==' ' || buf[i]=='\t')) |
2080 |
i++; |
2081 |
if (i >= len) |
2082 |
break; |
2083 |
start = i; |
2084 |
|
2085 |
p = buf+start; |
2086 |
while ((*p >= '0' && *p <= '9') || *p == '.') |
2087 |
p++; |
2088 |
*p = '\0'; |
2089 |
|
2090 |
#ifdef HAVE_INET_PTON |
2091 |
res = inet_pton(AF_INET, buf + start, |
2092 |
&net->nameserver_ipv4); |
2093 |
#else |
2094 |
res = inet_aton(buf + start, &net->nameserver_ipv4); |
2095 |
#endif |
2096 |
if (res < 1) |
2097 |
break; |
2098 |
|
2099 |
net->nameserver_known = 1; |
2100 |
break; |
2101 |
} |
2102 |
|
2103 |
for (i=0; i<len; i++) |
2104 |
if (strncmp(buf+i, "domain", 6) == 0) { |
2105 |
/* "domain" (1 or more whitespace) domain_name */ |
2106 |
i += 6; |
2107 |
while (i<len && (buf[i]==' ' || buf[i]=='\t')) |
2108 |
i++; |
2109 |
if (i >= len) |
2110 |
break; |
2111 |
|
2112 |
start = i; |
2113 |
while (i<len && buf[i]!='\n' && buf[i]!='\r') |
2114 |
i++; |
2115 |
if (i < len) |
2116 |
buf[i] = '\0'; |
2117 |
/* fatal("DOMAIN='%s'\n", buf + start); */ |
2118 |
net->domain_name = strdup(buf + start); |
2119 |
break; |
2120 |
} |
2121 |
} |
2122 |
|
2123 |
|
2124 |
/* |
2125 |
* net_add_nic(): |
2126 |
* |
2127 |
* Add a NIC to a network. (All NICs on a network will see each other's |
2128 |
* packets.) |
2129 |
*/ |
2130 |
void net_add_nic(struct net *net, void *extra, unsigned char *macaddr) |
2131 |
{ |
2132 |
if (net == NULL) |
2133 |
return; |
2134 |
|
2135 |
if (extra == NULL) { |
2136 |
fprintf(stderr, "net_add_nic(): extra = NULL\n"); |
2137 |
exit(1); |
2138 |
} |
2139 |
|
2140 |
net->n_nics ++; |
2141 |
net->nic_extra = realloc(net->nic_extra, sizeof(void *) |
2142 |
* net->n_nics); |
2143 |
if (net->nic_extra == NULL) { |
2144 |
fprintf(stderr, "net_add_nic(): out of memory\n"); |
2145 |
exit(1); |
2146 |
} |
2147 |
|
2148 |
net->nic_extra[net->n_nics - 1] = extra; |
2149 |
} |
2150 |
|
2151 |
|
2152 |
/* |
2153 |
* net_gateway_init(): |
2154 |
* |
2155 |
* This function creates a "gateway" machine (for example at IPv4 address |
2156 |
* 10.0.0.254, if the net is 10.0.0.0/8), which acts as a gateway/router/ |
2157 |
* nameserver etc. |
2158 |
*/ |
2159 |
static void net_gateway_init(struct net *net) |
2160 |
{ |
2161 |
unsigned char *p = (void *) &net->netmask_ipv4; |
2162 |
uint32_t x; |
2163 |
int xl; |
2164 |
|
2165 |
x = (p[0] << 24) + (p[1] << 16) + (p[2] << 8) + p[3]; |
2166 |
xl = 32 - net->netmask_ipv4_len; |
2167 |
if (xl > 8) |
2168 |
xl = 8; |
2169 |
x |= ((1 << xl) - 1) & ~1; |
2170 |
|
2171 |
net->gateway_ipv4_addr[0] = x >> 24; |
2172 |
net->gateway_ipv4_addr[1] = x >> 16; |
2173 |
net->gateway_ipv4_addr[2] = x >> 8; |
2174 |
net->gateway_ipv4_addr[3] = x; |
2175 |
|
2176 |
net->gateway_ethernet_addr[0] = 0x60; |
2177 |
net->gateway_ethernet_addr[1] = 0x50; |
2178 |
net->gateway_ethernet_addr[2] = 0x40; |
2179 |
net->gateway_ethernet_addr[3] = 0x30; |
2180 |
net->gateway_ethernet_addr[4] = 0x20; |
2181 |
net->gateway_ethernet_addr[5] = 0x10; |
2182 |
} |
2183 |
|
2184 |
|
2185 |
/* |
2186 |
* net_dumpinfo(): |
2187 |
* |
2188 |
* Called from the debugger's "machine" command, to print some info about |
2189 |
* a network. |
2190 |
*/ |
2191 |
void net_dumpinfo(struct net *net) |
2192 |
{ |
2193 |
int iadd = 4; |
2194 |
|
2195 |
debug("net: "); |
2196 |
|
2197 |
net_debugaddr(&net->netmask_ipv4, ADDR_IPV4); |
2198 |
debug("/%i", net->netmask_ipv4_len); |
2199 |
|
2200 |
debug(" (max outgoing: TCP=%i, UDP=%i)\n", |
2201 |
MAX_TCP_CONNECTIONS, MAX_UDP_CONNECTIONS); |
2202 |
|
2203 |
debug_indentation(iadd); |
2204 |
|
2205 |
debug("gateway: "); |
2206 |
net_debugaddr(&net->gateway_ipv4_addr, ADDR_IPV4); |
2207 |
debug(" ("); |
2208 |
net_debugaddr(&net->gateway_ethernet_addr, ADDR_ETHERNET); |
2209 |
debug(")\n"); |
2210 |
|
2211 |
debug_indentation(iadd); |
2212 |
if (net->domain_name != NULL && net->domain_name[0]) |
2213 |
debug("domain \"%s\", ", net->domain_name); |
2214 |
if (!net->nameserver_known) { |
2215 |
debug("(could not determine nameserver)"); |
2216 |
} else { |
2217 |
debug("nameserver "); |
2218 |
net_debugaddr(&net->nameserver_ipv4, ADDR_IPV4); |
2219 |
} |
2220 |
debug("\n"); |
2221 |
debug_indentation(-iadd); |
2222 |
|
2223 |
debug_indentation(-iadd); |
2224 |
} |
2225 |
|
2226 |
|
2227 |
/* |
2228 |
* net_init(): |
2229 |
* |
2230 |
* This function creates a network, and returns a pointer to it. |
2231 |
* Example: ipv4addr should be something like "10.0.0.0", netipv4len = 8. |
2232 |
* |
2233 |
* (On failure, exit() is called.) |
2234 |
*/ |
2235 |
struct net *net_init(struct emul *emul, int init_flags, |
2236 |
char *ipv4addr, int netipv4len) |
2237 |
{ |
2238 |
struct net *net; |
2239 |
int res; |
2240 |
|
2241 |
net = malloc(sizeof(struct net)); |
2242 |
if (net == NULL) { |
2243 |
fprintf(stderr, "net_init(): out of memory\n"); |
2244 |
exit(1); |
2245 |
} |
2246 |
|
2247 |
memset(net, 0, sizeof(struct net)); |
2248 |
|
2249 |
/* Set the back pointer: */ |
2250 |
net->emul = emul; |
2251 |
|
2252 |
/* Sane defaults: */ |
2253 |
net->timestamp = 0; |
2254 |
net->first_ethernet_packet = net->last_ethernet_packet = NULL; |
2255 |
|
2256 |
#ifdef HAVE_INET_PTON |
2257 |
res = inet_pton(AF_INET, ipv4addr, &net->netmask_ipv4); |
2258 |
#else |
2259 |
res = inet_aton(ipv4addr, &net->netmask_ipv4); |
2260 |
#endif |
2261 |
if (res < 1) { |
2262 |
fprintf(stderr, "net_init(): could not parse IPv4 address" |
2263 |
" '%s'\n", ipv4addr); |
2264 |
exit(1); |
2265 |
} |
2266 |
|
2267 |
if (netipv4len < 1 || netipv4len > 30) { |
2268 |
fprintf(stderr, "net_init(): extremely weird ipv4 " |
2269 |
"network length (%i)\n", netipv4len); |
2270 |
exit(1); |
2271 |
} |
2272 |
net->netmask_ipv4_len = netipv4len; |
2273 |
|
2274 |
net->nameserver_known = 0; |
2275 |
net->domain_name = ""; |
2276 |
parse_resolvconf(net); |
2277 |
|
2278 |
if (init_flags & NET_INIT_FLAG_GATEWAY) |
2279 |
net_gateway_init(net); |
2280 |
|
2281 |
net_dumpinfo(net); |
2282 |
|
2283 |
/* This is neccessary when using the real network: */ |
2284 |
signal(SIGPIPE, SIG_IGN); |
2285 |
|
2286 |
return net; |
2287 |
} |
2288 |
|