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/* |
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* Copyright (C) 2004-2006 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 1.89 2006/02/09 22:40:26 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: |
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* 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/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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* |
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* TODO 2: The following comments are old! Fix this. |
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* |
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* |
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* The emulated NIC has a MAC address of (for example) 10:20:30:00:00:10. |
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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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macbuf[0] = 0x10; |
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macbuf[1] = 0x20; |
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macbuf[2] = 0x30; |
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macbuf[3] = 0; |
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macbuf[4] = 0; |
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/* NOTE/TODO: This only allows 8 nics per machine! */ |
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macbuf[5] = (machine->serial_nr << 4) + (machine->nr_of_nics << 1); |
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|
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if (macbuf[0] & 1 || macbuf[5] & 1) { |
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fatal("Internal error in net_generate_unique_mac().\n"); |
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exit(1); |
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} |
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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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} |
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|
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|
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/* |
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* tcp_closeconnection(): |
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* |
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* Helper function which closes down a TCP connection completely. |
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*/ |
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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(): |
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* |
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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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*/ |
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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) |
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{ |
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struct ethernet_packet_link *lp; |
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int tcp_length, ip_len, option_len = 20; |
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|
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if (connecting) |
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net->tcp_connections[con_id].outside_acknr = |
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net->tcp_connections[con_id].inside_seqnr + 1; |
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|
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net->tcp_connections[con_id].tcp_id ++; |
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tcp_length = 20 + option_len + datalen; |
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ip_len = 20 + tcp_length; |
418 |
lp = net_allocate_packet_link(net, extra, 14 + ip_len); |
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|
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/* Ethernet header: */ |
421 |
memcpy(lp->data + 0, net->tcp_connections[con_id].ethernet_address, 6); |
422 |
memcpy(lp->data + 6, net->gateway_ethernet_addr, 6); |
423 |
lp->data[12] = 0x08; /* IP = 0x0800 */ |
424 |
lp->data[13] = 0x00; |
425 |
|
426 |
/* IP header: */ |
427 |
lp->data[14] = 0x45; /* ver */ |
428 |
lp->data[15] = 0x10; /* tos */ |
429 |
lp->data[16] = ip_len >> 8; |
430 |
lp->data[17] = ip_len & 0xff; |
431 |
lp->data[18] = net->tcp_connections[con_id].tcp_id >> 8; |
432 |
lp->data[19] = net->tcp_connections[con_id].tcp_id & 0xff; |
433 |
lp->data[20] = 0x40; /* don't fragment */ |
434 |
lp->data[21] = 0x00; |
435 |
lp->data[22] = 0x40; /* ttl */ |
436 |
lp->data[23] = 6; /* p = TCP */ |
437 |
memcpy(lp->data + 26, net->tcp_connections[con_id]. |
438 |
outside_ip_address, 4); |
439 |
memcpy(lp->data + 30, net->tcp_connections[con_id]. |
440 |
inside_ip_address, 4); |
441 |
net_ip_checksum(lp->data + 14, 10, 20); |
442 |
|
443 |
/* TCP header and options at offset 34: */ |
444 |
lp->data[34] = net->tcp_connections[con_id].outside_tcp_port >> 8; |
445 |
lp->data[35] = net->tcp_connections[con_id].outside_tcp_port & 0xff; |
446 |
lp->data[36] = net->tcp_connections[con_id].inside_tcp_port >> 8; |
447 |
lp->data[37] = net->tcp_connections[con_id].inside_tcp_port & 0xff; |
448 |
lp->data[38] = (net->tcp_connections[con_id]. |
449 |
outside_seqnr >> 24) & 0xff; |
450 |
lp->data[39] = (net->tcp_connections[con_id]. |
451 |
outside_seqnr >> 16) & 0xff; |
452 |
lp->data[40] = (net->tcp_connections[con_id]. |
453 |
outside_seqnr >> 8) & 0xff; |
454 |
lp->data[41] = net->tcp_connections[con_id]. |
455 |
outside_seqnr & 0xff; |
456 |
lp->data[42] = (net->tcp_connections[con_id]. |
457 |
outside_acknr >> 24) & 0xff; |
458 |
lp->data[43] = (net->tcp_connections[con_id]. |
459 |
outside_acknr >> 16) & 0xff; |
460 |
lp->data[44] = (net->tcp_connections[con_id]. |
461 |
outside_acknr >> 8) & 0xff; |
462 |
lp->data[45] = net->tcp_connections[con_id].outside_acknr & 0xff; |
463 |
|
464 |
/* Control */ |
465 |
lp->data[46] = (option_len + 20) / 4 * 0x10; |
466 |
lp->data[47] = 0x10; /* ACK */ |
467 |
if (connecting) |
468 |
lp->data[47] |= 0x02; /* SYN */ |
469 |
if (net->tcp_connections[con_id].state == TCP_OUTSIDE_CONNECTED) |
470 |
lp->data[47] |= 0x08; /* PSH */ |
471 |
if (rst) |
472 |
lp->data[47] |= 0x04; /* RST */ |
473 |
if (net->tcp_connections[con_id].state >= TCP_OUTSIDE_DISCONNECTED) |
474 |
lp->data[47] |= 0x01; /* FIN */ |
475 |
|
476 |
/* Window */ |
477 |
lp->data[48] = 0x10; |
478 |
lp->data[49] = 0x00; |
479 |
|
480 |
/* no urgent ptr */ |
481 |
|
482 |
/* options */ |
483 |
/* TODO: HAHA, this is ugly */ |
484 |
lp->data[54] = 0x02; |
485 |
lp->data[55] = 0x04; |
486 |
lp->data[56] = 0x05; |
487 |
lp->data[57] = 0xb4; |
488 |
lp->data[58] = 0x01; |
489 |
lp->data[59] = 0x03; |
490 |
lp->data[60] = 0x03; |
491 |
lp->data[61] = 0x00; |
492 |
lp->data[62] = 0x01; |
493 |
lp->data[63] = 0x01; |
494 |
lp->data[64] = 0x08; |
495 |
lp->data[65] = 0x0a; |
496 |
lp->data[66] = (net->timestamp >> 24) & 0xff; |
497 |
lp->data[67] = (net->timestamp >> 16) & 0xff; |
498 |
lp->data[68] = (net->timestamp >> 8) & 0xff; |
499 |
lp->data[69] = net->timestamp & 0xff; |
500 |
lp->data[70] = (net->tcp_connections[con_id]. |
501 |
inside_timestamp >> 24) & 0xff; |
502 |
lp->data[71] = (net->tcp_connections[con_id]. |
503 |
inside_timestamp >> 16) & 0xff; |
504 |
lp->data[72] = (net->tcp_connections[con_id]. |
505 |
inside_timestamp >> 8) & 0xff; |
506 |
lp->data[73] = net->tcp_connections[con_id]. |
507 |
inside_timestamp & 0xff; |
508 |
|
509 |
/* data: */ |
510 |
if (data != NULL) { |
511 |
memcpy(lp->data + 74, data, datalen); |
512 |
net->tcp_connections[con_id].outside_seqnr += datalen; |
513 |
} |
514 |
|
515 |
/* Checksum: */ |
516 |
net_ip_tcp_checksum(lp->data + 34, 16, tcp_length, |
517 |
lp->data + 26, lp->data + 30, 0); |
518 |
|
519 |
#if 0 |
520 |
{ |
521 |
int i; |
522 |
fatal("[ net_ip_tcp_connectionreply(%i): ", connecting); |
523 |
for (i=0; i<ip_len+14; i++) |
524 |
fatal("%02x", lp->data[i]); |
525 |
fatal(" ]\n"); |
526 |
} |
527 |
#endif |
528 |
|
529 |
if (connecting) |
530 |
net->tcp_connections[con_id].outside_seqnr ++; |
531 |
} |
532 |
|
533 |
|
534 |
/* |
535 |
* net_ip_tcp(): |
536 |
* |
537 |
* Handle a TCP packet comming from the emulated OS. |
538 |
* |
539 |
* The IP header (at offset 14) could look something like |
540 |
* |
541 |
* ver=45 tos=00 len=003c id=0006 ofs=0000 ttl=40 p=11 sum=b798 |
542 |
* src=0a000001 dst=c1abcdef |
543 |
* |
544 |
* TCP header, at offset 34: |
545 |
* |
546 |
* srcport=fffe dstport=0015 seqnr=af419a1d acknr=00000000 |
547 |
* control=a002 window=4000 checksum=fe58 urgent=0000 |
548 |
* and then "options and padding" and then data. |
549 |
* (020405b4010303000101080a0000000000000000) |
550 |
* |
551 |
* See the following URLs for good descriptions of TCP: |
552 |
* |
553 |
* http://www.networksorcery.com/enp/protocol/tcp.htm |
554 |
* http://www.tcpipguide.com/free/t_TCPIPTransmissionControlProtocolTCP.htm |
555 |
*/ |
556 |
static void net_ip_tcp(struct net *net, void *extra, |
557 |
unsigned char *packet, int len) |
558 |
{ |
559 |
int con_id, free_con_id, i, res; |
560 |
int srcport, dstport, data_offset, window, checksum, urgptr; |
561 |
int syn, ack, psh, rst, urg, fin; |
562 |
uint32_t seqnr, acknr; |
563 |
struct sockaddr_in remote_ip; |
564 |
fd_set rfds; |
565 |
struct timeval tv; |
566 |
int send_ofs; |
567 |
|
568 |
#if 0 |
569 |
fatal("[ net: TCP: "); |
570 |
for (i=0; i<26; i++) |
571 |
fatal("%02x", packet[i]); |
572 |
fatal(" "); |
573 |
#endif |
574 |
|
575 |
srcport = (packet[34] << 8) + packet[35]; |
576 |
dstport = (packet[36] << 8) + packet[37]; |
577 |
|
578 |
seqnr = (packet[38] << 24) + (packet[39] << 16) |
579 |
+ (packet[40] << 8) + packet[41]; |
580 |
acknr = (packet[42] << 24) + (packet[43] << 16) |
581 |
+ (packet[44] << 8) + packet[45]; |
582 |
|
583 |
#if 0 |
584 |
fatal("%i.%i.%i.%i:%i -> %i.%i.%i.%i:%i, seqnr=%lli acknr=%lli ", |
585 |
packet[26], packet[27], packet[28], packet[29], srcport, |
586 |
packet[30], packet[31], packet[32], packet[33], dstport, |
587 |
(long long)seqnr, (long long)acknr); |
588 |
#endif |
589 |
|
590 |
data_offset = (packet[46] >> 4) * 4 + 34; |
591 |
/* data_offset is now data offset within packet :-) */ |
592 |
|
593 |
urg = packet[47] & 32; |
594 |
ack = packet[47] & 16; |
595 |
psh = packet[47] & 8; |
596 |
rst = packet[47] & 4; |
597 |
syn = packet[47] & 2; |
598 |
fin = packet[47] & 1; |
599 |
window = (packet[48] << 8) + packet[49]; |
600 |
checksum = (packet[50] << 8) + packet[51]; |
601 |
urgptr = (packet[52] << 8) + packet[53]; |
602 |
|
603 |
#if 0 |
604 |
fatal(urg? "URG " : ""); |
605 |
fatal(ack? "ACK " : ""); |
606 |
fatal(psh? "PSH " : ""); |
607 |
fatal(rst? "RST " : ""); |
608 |
fatal(syn? "SYN " : ""); |
609 |
fatal(fin? "FIN " : ""); |
610 |
|
611 |
fatal("window=0x%04x checksum=0x%04x urgptr=0x%04x ", |
612 |
window, checksum, urgptr); |
613 |
|
614 |
fatal("options="); |
615 |
for (i=34+20; i<data_offset; i++) |
616 |
fatal("%02x", packet[i]); |
617 |
|
618 |
fatal(" data="); |
619 |
for (i=data_offset; i<len; i++) |
620 |
fatal("%02x", packet[i]); |
621 |
|
622 |
fatal(" ]\n"); |
623 |
#endif |
624 |
|
625 |
net_ip_tcp_checksum(packet + 34, 16, len - 34, |
626 |
packet + 26, packet + 30, 0); |
627 |
if (packet[50] * 256 + packet[51] != checksum) { |
628 |
debug("TCP: dropping packet because of checksum mismatch " |
629 |
"(0x%04x != 0x%04x)\n", packet[50] * 256 + packet[51], |
630 |
checksum); |
631 |
|
632 |
return; |
633 |
} |
634 |
|
635 |
/* Does this packet belong to a current connection? */ |
636 |
con_id = free_con_id = -1; |
637 |
for (i=0; i<MAX_TCP_CONNECTIONS; i++) { |
638 |
if (!net->tcp_connections[i].in_use) |
639 |
free_con_id = i; |
640 |
if (net->tcp_connections[i].in_use && |
641 |
net->tcp_connections[i].inside_tcp_port == srcport && |
642 |
net->tcp_connections[i].outside_tcp_port == dstport && |
643 |
memcmp(net->tcp_connections[i].inside_ip_address, |
644 |
packet + 26, 4) == 0 && |
645 |
memcmp(net->tcp_connections[i].outside_ip_address, |
646 |
packet + 30, 4) == 0) { |
647 |
con_id = i; |
648 |
break; |
649 |
} |
650 |
} |
651 |
|
652 |
/* |
653 |
* Unknown connection, and not SYN? Then drop the packet. |
654 |
* TODO: Send back RST? |
655 |
*/ |
656 |
if (con_id < 0 && !syn) { |
657 |
debug("[ net: TCP: dropping packet from unknown connection," |
658 |
" %i.%i.%i.%i:%i -> %i.%i.%i.%i:%i %s%s%s%s%s]\n", |
659 |
packet[26], packet[27], packet[28], packet[29], srcport, |
660 |
packet[30], packet[31], packet[32], packet[33], dstport, |
661 |
fin? "FIN ": "", syn? "SYN ": "", ack? "ACK ": "", |
662 |
psh? "PSH ": "", rst? "RST ": ""); |
663 |
return; |
664 |
} |
665 |
|
666 |
/* Known connection, and SYN? Then ignore the packet. */ |
667 |
if (con_id >= 0 && syn) { |
668 |
debug("[ net: TCP: ignoring redundant SYN packet from known" |
669 |
" connection, %i.%i.%i.%i:%i -> %i.%i.%i.%i:%i ]\n", |
670 |
packet[26], packet[27], packet[28], packet[29], srcport, |
671 |
packet[30], packet[31], packet[32], packet[33], dstport); |
672 |
return; |
673 |
} |
674 |
|
675 |
/* |
676 |
* A new outgoing connection? |
677 |
*/ |
678 |
if (con_id < 0 && syn) { |
679 |
debug("[ net: TCP: new outgoing connection, %i.%i.%i.%i:%i" |
680 |
" -> %i.%i.%i.%i:%i ]\n", |
681 |
packet[26], packet[27], packet[28], packet[29], srcport, |
682 |
packet[30], packet[31], packet[32], packet[33], dstport); |
683 |
|
684 |
/* Find a free connection id to use: */ |
685 |
if (free_con_id < 0) { |
686 |
#if 1 |
687 |
/* |
688 |
* TODO: Reuse the oldest one currently in use, or |
689 |
* just drop the new connection attempt? Drop for now. |
690 |
*/ |
691 |
fatal("[ TOO MANY TCP CONNECTIONS IN USE! " |
692 |
"Increase MAX_TCP_CONNECTIONS! ]\n"); |
693 |
return; |
694 |
#else |
695 |
int i; |
696 |
int64_t oldest = net-> |
697 |
tcp_connections[0].last_used_timestamp; |
698 |
free_con_id = 0; |
699 |
|
700 |
fatal("[ NO FREE TCP SLOTS, REUSING OLDEST ONE ]\n"); |
701 |
for (i=0; i<MAX_TCP_CONNECTIONS; i++) |
702 |
if (net->tcp_connections[i]. |
703 |
last_used_timestamp < oldest) { |
704 |
oldest = net->tcp_connections[i]. |
705 |
last_used_timestamp; |
706 |
free_con_id = i; |
707 |
} |
708 |
tcp_closeconnection(net, free_con_id); |
709 |
#endif |
710 |
} |
711 |
|
712 |
con_id = free_con_id; |
713 |
memset(&net->tcp_connections[con_id], 0, |
714 |
sizeof(struct tcp_connection)); |
715 |
|
716 |
memcpy(net->tcp_connections[con_id].ethernet_address, |
717 |
packet + 6, 6); |
718 |
memcpy(net->tcp_connections[con_id].inside_ip_address, |
719 |
packet + 26, 4); |
720 |
net->tcp_connections[con_id].inside_tcp_port = srcport; |
721 |
memcpy(net->tcp_connections[con_id].outside_ip_address, |
722 |
packet + 30, 4); |
723 |
net->tcp_connections[con_id].outside_tcp_port = dstport; |
724 |
|
725 |
net->tcp_connections[con_id].socket = |
726 |
socket(AF_INET, SOCK_STREAM, 0); |
727 |
if (net->tcp_connections[con_id].socket < 0) { |
728 |
fatal("[ net: TCP: socket() returned %i ]\n", |
729 |
net->tcp_connections[con_id].socket); |
730 |
return; |
731 |
} |
732 |
|
733 |
debug("[ new tcp outgoing socket=%i ]\n", |
734 |
net->tcp_connections[con_id].socket); |
735 |
|
736 |
net->tcp_connections[con_id].in_use = 1; |
737 |
|
738 |
/* Set the socket to non-blocking: */ |
739 |
res = fcntl(net->tcp_connections[con_id].socket, F_GETFL); |
740 |
fcntl(net->tcp_connections[con_id].socket, F_SETFL, |
741 |
res | O_NONBLOCK); |
742 |
|
743 |
remote_ip.sin_family = AF_INET; |
744 |
memcpy((unsigned char *)&remote_ip.sin_addr, |
745 |
net->tcp_connections[con_id].outside_ip_address, 4); |
746 |
remote_ip.sin_port = htons( |
747 |
net->tcp_connections[con_id].outside_tcp_port); |
748 |
|
749 |
res = connect(net->tcp_connections[con_id].socket, |
750 |
(struct sockaddr *)&remote_ip, sizeof(remote_ip)); |
751 |
|
752 |
/* connect can return -1, and errno = EINPROGRESS |
753 |
as we might not have connected right away. */ |
754 |
|
755 |
net->tcp_connections[con_id].state = |
756 |
TCP_OUTSIDE_TRYINGTOCONNECT; |
757 |
|
758 |
net->tcp_connections[con_id].outside_acknr = 0; |
759 |
net->tcp_connections[con_id].outside_seqnr = |
760 |
((random() & 0xffff) << 16) + (random() & 0xffff); |
761 |
} |
762 |
|
763 |
if (rst) { |
764 |
debug("[ 'rst': disconnecting TCP connection %i ]\n", con_id); |
765 |
net_ip_tcp_connectionreply(net, extra, con_id, 0, NULL, 0, 1); |
766 |
tcp_closeconnection(net, con_id); |
767 |
return; |
768 |
} |
769 |
|
770 |
if (ack && net->tcp_connections[con_id].state |
771 |
== TCP_OUTSIDE_DISCONNECTED2) { |
772 |
debug("[ 'ack': guestOS's final termination of TCP " |
773 |
"connection %i ]\n", con_id); |
774 |
|
775 |
/* Send an RST? (TODO, this is wrong...) */ |
776 |
net_ip_tcp_connectionreply(net, extra, con_id, 0, NULL, 0, 1); |
777 |
|
778 |
/* ... and forget about this connection: */ |
779 |
tcp_closeconnection(net, con_id); |
780 |
return; |
781 |
} |
782 |
|
783 |
if (fin && net->tcp_connections[con_id].state |
784 |
== TCP_OUTSIDE_DISCONNECTED) { |
785 |
debug("[ 'fin': response to outside's disconnection of " |
786 |
"TCP connection %i ]\n", con_id); |
787 |
|
788 |
/* Send an ACK: */ |
789 |
net->tcp_connections[con_id].state = TCP_OUTSIDE_CONNECTED; |
790 |
net_ip_tcp_connectionreply(net, extra, con_id, 0, NULL, 0, 0); |
791 |
net->tcp_connections[con_id].state = TCP_OUTSIDE_DISCONNECTED2; |
792 |
return; |
793 |
} |
794 |
|
795 |
if (fin) { |
796 |
debug("[ 'fin': guestOS disconnecting TCP connection %i ]\n", |
797 |
con_id); |
798 |
|
799 |
/* Send ACK: */ |
800 |
net_ip_tcp_connectionreply(net, extra, con_id, 0, NULL, 0, 0); |
801 |
net->tcp_connections[con_id].state = TCP_OUTSIDE_DISCONNECTED2; |
802 |
|
803 |
/* Return and send FIN: */ |
804 |
goto ret; |
805 |
} |
806 |
|
807 |
if (ack) { |
808 |
debug("ACK %i bytes, inside_acknr=%u outside_seqnr=%u\n", |
809 |
net->tcp_connections[con_id].incoming_buf_len, |
810 |
net->tcp_connections[con_id].inside_acknr, |
811 |
net->tcp_connections[con_id].outside_seqnr); |
812 |
net->tcp_connections[con_id].inside_acknr = acknr; |
813 |
if (net->tcp_connections[con_id].inside_acknr == |
814 |
net->tcp_connections[con_id].outside_seqnr && |
815 |
net->tcp_connections[con_id].incoming_buf_len != 0) { |
816 |
debug(" all acked\n"); |
817 |
net->tcp_connections[con_id].incoming_buf_len = 0; |
818 |
} |
819 |
} |
820 |
|
821 |
net->tcp_connections[con_id].inside_seqnr = seqnr; |
822 |
|
823 |
/* TODO: This is hardcoded for a specific NetBSD packet: */ |
824 |
if (packet[34 + 30] == 0x08 && packet[34 + 31] == 0x0a) |
825 |
net->tcp_connections[con_id].inside_timestamp = |
826 |
(packet[34 + 32 + 0] << 24) + |
827 |
(packet[34 + 32 + 1] << 16) + |
828 |
(packet[34 + 32 + 2] << 8) + |
829 |
(packet[34 + 32 + 3] << 0); |
830 |
|
831 |
|
832 |
net->timestamp ++; |
833 |
net->tcp_connections[con_id].last_used_timestamp = net->timestamp; |
834 |
|
835 |
|
836 |
if (net->tcp_connections[con_id].state != TCP_OUTSIDE_CONNECTED) { |
837 |
debug("[ not connected to outside ]\n"); |
838 |
return; |
839 |
} |
840 |
|
841 |
|
842 |
if (data_offset >= len) |
843 |
return; |
844 |
|
845 |
|
846 |
/* |
847 |
* We are here if this is a known connection, and data is to be |
848 |
* transmitted to the outside world. |
849 |
*/ |
850 |
|
851 |
send_ofs = data_offset; |
852 |
send_ofs += ((int32_t)net->tcp_connections[con_id].outside_acknr |
853 |
- (int32_t)seqnr); |
854 |
#if 1 |
855 |
debug("[ %i bytes of tcp data to be sent, beginning at seqnr %u, ", |
856 |
len - data_offset, seqnr); |
857 |
debug("outside is at acknr %u ==> %i actual bytes to be sent ]\n", |
858 |
net->tcp_connections[con_id].outside_acknr, len - send_ofs); |
859 |
#endif |
860 |
|
861 |
/* Drop outgoing packet if the guest OS' seqnr is not |
862 |
the same as we have acked. (We have missed something, perhaps.) */ |
863 |
if (seqnr != net->tcp_connections[con_id].outside_acknr) { |
864 |
debug("!! outgoing TCP packet dropped (seqnr = %u, " |
865 |
"outside_acknr = %u)\n", seqnr, |
866 |
net->tcp_connections[con_id].outside_acknr); |
867 |
goto ret; |
868 |
} |
869 |
|
870 |
if (len - send_ofs > 0) { |
871 |
/* Is the socket available for output? */ |
872 |
FD_ZERO(&rfds); /* write */ |
873 |
FD_SET(net->tcp_connections[con_id].socket, &rfds); |
874 |
tv.tv_sec = tv.tv_usec = 0; |
875 |
errno = 0; |
876 |
res = select(net->tcp_connections[con_id].socket+1, |
877 |
NULL, &rfds, NULL, &tv); |
878 |
if (res < 1) { |
879 |
net->tcp_connections[con_id].state = |
880 |
TCP_OUTSIDE_DISCONNECTED; |
881 |
debug("[ TCP: disconnect on select for writing ]\n"); |
882 |
goto ret; |
883 |
} |
884 |
|
885 |
res = write(net->tcp_connections[con_id].socket, |
886 |
packet + send_ofs, len - send_ofs); |
887 |
|
888 |
if (res > 0) { |
889 |
net->tcp_connections[con_id].outside_acknr += res; |
890 |
} else if (errno == EAGAIN) { |
891 |
/* Just ignore this attempt. */ |
892 |
return; |
893 |
} else { |
894 |
debug("[ error writing %i bytes to TCP connection %i:" |
895 |
" errno = %i ]\n", len - send_ofs, con_id, errno); |
896 |
net->tcp_connections[con_id].state = |
897 |
TCP_OUTSIDE_DISCONNECTED; |
898 |
debug("[ TCP: disconnect on write() ]\n"); |
899 |
goto ret; |
900 |
} |
901 |
} |
902 |
|
903 |
ret: |
904 |
/* Send an ACK (or FIN) to the guest OS: */ |
905 |
net_ip_tcp_connectionreply(net, extra, con_id, 0, NULL, 0, 0); |
906 |
} |
907 |
|
908 |
|
909 |
/* |
910 |
* net_ip_udp(): |
911 |
* |
912 |
* Handle a UDP packet. |
913 |
* |
914 |
* (See http://www.networksorcery.com/enp/protocol/udp.htm.) |
915 |
* |
916 |
* The IP header (at offset 14) could look something like |
917 |
* |
918 |
* ver=45 tos=00 len=003c id=0006 ofs=0000 ttl=40 p=11 sum=b798 |
919 |
* src=0a000001 dst=c1abcdef |
920 |
* |
921 |
* and the UDP data (beginning at offset 34): |
922 |
* |
923 |
* srcport=fffc dstport=0035 length=0028 chksum=76b6 |
924 |
* 43e20100000100000000000003667470066e6574627364036f726700001c0001 |
925 |
*/ |
926 |
static void net_ip_udp(struct net *net, void *extra, |
927 |
unsigned char *packet, int len) |
928 |
{ |
929 |
int con_id, free_con_id, i, srcport, dstport, udp_len; |
930 |
ssize_t res; |
931 |
struct sockaddr_in remote_ip; |
932 |
|
933 |
if ((packet[20] & 0x3f) != 0) { |
934 |
fatal("[ net_ip_udp(): WARNING! fragmented UDP " |
935 |
"packet, TODO ]\n"); |
936 |
return; |
937 |
} |
938 |
|
939 |
srcport = (packet[34] << 8) + packet[35]; |
940 |
dstport = (packet[36] << 8) + packet[37]; |
941 |
udp_len = (packet[38] << 8) + packet[39]; |
942 |
/* chksum at offset 40 and 41 */ |
943 |
|
944 |
debug("[ net: UDP: "); |
945 |
debug("srcport=%i dstport=%i len=%i ", srcport, dstport, udp_len); |
946 |
for (i=42; i<len; i++) { |
947 |
if (packet[i] >= ' ' && packet[i] < 127) |
948 |
debug("%c", packet[i]); |
949 |
else |
950 |
debug("[%02x]", packet[i]); |
951 |
} |
952 |
debug(" ]\n"); |
953 |
|
954 |
/* Is this "connection" new, or a currently ongoing one? */ |
955 |
con_id = free_con_id = -1; |
956 |
for (i=0; i<MAX_UDP_CONNECTIONS; i++) { |
957 |
if (!net->udp_connections[i].in_use) |
958 |
free_con_id = i; |
959 |
if (net->udp_connections[i].in_use && |
960 |
net->udp_connections[i].inside_udp_port == srcport && |
961 |
net->udp_connections[i].outside_udp_port == dstport && |
962 |
memcmp(net->udp_connections[i].inside_ip_address, |
963 |
packet + 26, 4) == 0 && |
964 |
memcmp(net->udp_connections[i].outside_ip_address, |
965 |
packet + 30, 4) == 0) { |
966 |
con_id = i; |
967 |
break; |
968 |
} |
969 |
} |
970 |
|
971 |
debug("&& UDP connection is "); |
972 |
if (con_id >= 0) |
973 |
debug("ONGOING"); |
974 |
else { |
975 |
debug("NEW"); |
976 |
if (free_con_id < 0) { |
977 |
int i; |
978 |
int64_t oldest = net-> |
979 |
udp_connections[0].last_used_timestamp; |
980 |
free_con_id = 0; |
981 |
|
982 |
debug(", NO FREE SLOTS, REUSING OLDEST ONE"); |
983 |
for (i=0; i<MAX_UDP_CONNECTIONS; i++) |
984 |
if (net->udp_connections[i]. |
985 |
last_used_timestamp < oldest) { |
986 |
oldest = net->udp_connections[i]. |
987 |
last_used_timestamp; |
988 |
free_con_id = i; |
989 |
} |
990 |
close(net->udp_connections[free_con_id].socket); |
991 |
} |
992 |
con_id = free_con_id; |
993 |
memset(&net->udp_connections[con_id], 0, |
994 |
sizeof(struct udp_connection)); |
995 |
|
996 |
memcpy(net->udp_connections[con_id].ethernet_address, |
997 |
packet + 6, 6); |
998 |
memcpy(net->udp_connections[con_id].inside_ip_address, |
999 |
packet + 26, 4); |
1000 |
net->udp_connections[con_id].inside_udp_port = srcport; |
1001 |
memcpy(net->udp_connections[con_id].outside_ip_address, |
1002 |
packet + 30, 4); |
1003 |
net->udp_connections[con_id].outside_udp_port = dstport; |
1004 |
|
1005 |
net->udp_connections[con_id].socket = socket(AF_INET, |
1006 |
SOCK_DGRAM, 0); |
1007 |
if (net->udp_connections[con_id].socket < 0) { |
1008 |
fatal("[ net: UDP: socket() returned %i ]\n", |
1009 |
net->udp_connections[con_id].socket); |
1010 |
return; |
1011 |
} |
1012 |
|
1013 |
debug(" {socket=%i}", net->udp_connections[con_id].socket); |
1014 |
|
1015 |
net->udp_connections[con_id].in_use = 1; |
1016 |
|
1017 |
/* Set the socket to non-blocking: */ |
1018 |
res = fcntl(net->udp_connections[con_id].socket, F_GETFL); |
1019 |
fcntl(net->udp_connections[con_id].socket, F_SETFL, |
1020 |
res | O_NONBLOCK); |
1021 |
} |
1022 |
|
1023 |
debug(", connection id %i\n", con_id); |
1024 |
|
1025 |
net->timestamp ++; |
1026 |
net->udp_connections[con_id].last_used_timestamp = net->timestamp; |
1027 |
|
1028 |
remote_ip.sin_family = AF_INET; |
1029 |
memcpy((unsigned char *)&remote_ip.sin_addr, |
1030 |
net->udp_connections[con_id].outside_ip_address, 4); |
1031 |
|
1032 |
/* |
1033 |
* Special case for the nameserver: If a UDP packet is sent to |
1034 |
* the gateway, it will be forwarded to the nameserver, if it is |
1035 |
* known. |
1036 |
*/ |
1037 |
if (net->nameserver_known && |
1038 |
memcmp(net->udp_connections[con_id].outside_ip_address, |
1039 |
&net->gateway_ipv4_addr[0], 4) == 0) { |
1040 |
memcpy((unsigned char *)&remote_ip.sin_addr, |
1041 |
&net->nameserver_ipv4, 4); |
1042 |
net->udp_connections[con_id].fake_ns = 1; |
1043 |
} |
1044 |
|
1045 |
remote_ip.sin_port = htons( |
1046 |
net->udp_connections[con_id].outside_udp_port); |
1047 |
|
1048 |
res = sendto(net->udp_connections[con_id].socket, packet + 42, |
1049 |
len - 42, 0, (const struct sockaddr *)&remote_ip, |
1050 |
sizeof(remote_ip)); |
1051 |
|
1052 |
if (res != len-42) |
1053 |
debug("[ net: UDP: unable to send %i bytes ]\n", len-42); |
1054 |
else |
1055 |
debug("[ net: UDP: OK!!! ]\n"); |
1056 |
} |
1057 |
|
1058 |
|
1059 |
/* |
1060 |
* net_ip(): |
1061 |
* |
1062 |
* Handle an IP packet, coming from the emulated NIC. |
1063 |
*/ |
1064 |
static void net_ip(struct net *net, void *extra, |
1065 |
unsigned char *packet, int len) |
1066 |
{ |
1067 |
#if 1 |
1068 |
int i; |
1069 |
|
1070 |
debug("[ net: IP: "); |
1071 |
debug("ver=%02x ", packet[14]); |
1072 |
debug("tos=%02x ", packet[15]); |
1073 |
debug("len=%02x%02x ", packet[16], packet[17]); |
1074 |
debug("id=%02x%02x ", packet[18], packet[19]); |
1075 |
debug("ofs=%02x%02x ", packet[20], packet[21]); |
1076 |
debug("ttl=%02x ", packet[22]); |
1077 |
debug("p=%02x ", packet[23]); |
1078 |
debug("sum=%02x%02x ", packet[24], packet[25]); |
1079 |
debug("src=%02x%02x%02x%02x ", |
1080 |
packet[26], packet[27], packet[28], packet[29]); |
1081 |
debug("dst=%02x%02x%02x%02x ", |
1082 |
packet[30], packet[31], packet[32], packet[33]); |
1083 |
for (i=34; i<len; i++) |
1084 |
debug("%02x", packet[i]); |
1085 |
debug(" ]\n"); |
1086 |
#endif |
1087 |
|
1088 |
/* Cut off overflowing tail data: */ |
1089 |
if (len > 14 + packet[16]*256 + packet[17]) |
1090 |
len = 14 + packet[16]*256 + packet[17]; |
1091 |
|
1092 |
if (packet[14] == 0x45) { |
1093 |
/* IPv4: */ |
1094 |
switch (packet[23]) { |
1095 |
case 1: /* ICMP */ |
1096 |
net_ip_icmp(net, extra, packet, len); |
1097 |
break; |
1098 |
case 6: /* TCP */ |
1099 |
net_ip_tcp(net, extra, packet, len); |
1100 |
break; |
1101 |
case 17:/* UDP */ |
1102 |
net_ip_udp(net, extra, packet, len); |
1103 |
break; |
1104 |
default: |
1105 |
fatal("[ net: IP: UNIMPLEMENTED protocol %i ]\n", |
1106 |
packet[23]); |
1107 |
} |
1108 |
} else |
1109 |
fatal("[ net: IP: UNIMPLEMENTED ip, first byte = 0x%02x ]\n", |
1110 |
packet[14]); |
1111 |
} |
1112 |
|
1113 |
|
1114 |
/* |
1115 |
* net_ip_broadcast_dhcp(): |
1116 |
* |
1117 |
* Handle an IPv4 DHCP broadcast packet, coming from the emulated NIC. |
1118 |
* |
1119 |
* Read http://www.ietf.org/rfc/rfc2131.txt for details on DHCP. |
1120 |
* (And http://users.telenet.be/mydotcom/library/network/dhcp.htm.) |
1121 |
*/ |
1122 |
static void net_ip_broadcast_dhcp(struct net *net, void *extra, |
1123 |
unsigned char *packet, int len) |
1124 |
{ |
1125 |
/* |
1126 |
* TODO |
1127 |
*/ |
1128 |
#if 0 |
1129 |
struct ethernet_packet_link *lp; |
1130 |
int i; |
1131 |
|
1132 |
fatal("[ net: IPv4 DHCP: "); |
1133 |
#if 0 |
1134 |
fatal("ver=%02x ", packet[14]); |
1135 |
fatal("tos=%02x ", packet[15]); |
1136 |
fatal("len=%02x%02x ", packet[16], packet[17]); |
1137 |
fatal("id=%02x%02x ", packet[18], packet[19]); |
1138 |
fatal("ofs=%02x%02x ", packet[20], packet[21]); |
1139 |
fatal("ttl=%02x ", packet[22]); |
1140 |
fatal("p=%02x ", packet[23]); |
1141 |
fatal("sum=%02x%02x ", packet[24], packet[25]); |
1142 |
#endif |
1143 |
fatal("src=%02x%02x%02x%02x ", |
1144 |
packet[26], packet[27], packet[28], packet[29]); |
1145 |
fatal("dst=%02x%02x%02x%02x ", |
1146 |
packet[30], packet[31], packet[32], packet[33]); |
1147 |
#if 0 |
1148 |
for (i=34; i<len; i++) |
1149 |
fatal("%02x", packet[i]); |
1150 |
#endif |
1151 |
|
1152 |
if (len < 34 + 8 + 236) { |
1153 |
fatal("[ DHCP packet too short? Len=%i ]\n", len); |
1154 |
return; |
1155 |
} |
1156 |
|
1157 |
/* |
1158 |
* UDP data (at offset 34): |
1159 |
* |
1160 |
* srcport=0044 dstport=0043 length=0134 chksum=a973 |
1161 |
* data = 01010600d116d276000000000000000000000000000000 |
1162 |
* 0000000000102030405060...0000...638253633501...000 |
1163 |
*/ |
1164 |
|
1165 |
fatal("op=%02x ", packet[42]); |
1166 |
fatal("htype=%02x ", packet[43]); |
1167 |
fatal("hlen=%02x ", packet[44]); |
1168 |
fatal("hops=%02x ", packet[45]); |
1169 |
fatal("xid=%02x%02x%02x%02x ", packet[46], packet[47], |
1170 |
packet[48], packet[49]); |
1171 |
fatal("secs=%02x%02x ", packet[50], packet[51]); |
1172 |
fatal("flags=%02x%02x ", packet[52], packet[53]); |
1173 |
fatal("ciaddr=%02x%02x%02x%02x ", packet[54], packet[55], |
1174 |
packet[56], packet[57]); |
1175 |
fatal("yiaddr=%02x%02x%02x%02x ", packet[58], packet[59], |
1176 |
packet[60], packet[61]); |
1177 |
fatal("siaddr=%02x%02x%02x%02x ", packet[62], packet[63], |
1178 |
packet[64], packet[65]); |
1179 |
fatal("giaddr=%02x%02x%02x%02x ", packet[66], packet[67], |
1180 |
packet[68], packet[69]); |
1181 |
fatal("chaddr="); |
1182 |
for (i=70; i<70+16; i++) |
1183 |
fatal("%02x", packet[i]); |
1184 |
/* |
1185 |
| sname (64) | |
1186 |
| file (128) | |
1187 |
*/ |
1188 |
fatal(" ]\n"); |
1189 |
|
1190 |
lp = net_allocate_packet_link(net, extra, len); |
1191 |
|
1192 |
/* Copy the old packet first: */ |
1193 |
memcpy(lp->data, packet, len); |
1194 |
|
1195 |
/* We are sending to the client, from the gateway: */ |
1196 |
memcpy(lp->data + 0, packet + 6, 6); |
1197 |
memcpy(lp->data + 6, net->gateway_ethernet_addr, 6); |
1198 |
|
1199 |
memcpy(lp->data + 26, &net->gateway_ipv4_addr[0], 4); |
1200 |
lp->data[30] = 0xff; |
1201 |
lp->data[31] = 0xff; |
1202 |
lp->data[32] = 0xff; |
1203 |
lp->data[33] = 0xff; |
1204 |
|
1205 |
/* Switch src and dst ports: */ |
1206 |
memcpy(lp->data + 34, packet + 36, 2); |
1207 |
memcpy(lp->data + 36, packet + 34, 2); |
1208 |
|
1209 |
/* Client's (yiaddr) IPv4 address: */ |
1210 |
lp->data[58] = 10; |
1211 |
lp->data[59] = 0; |
1212 |
lp->data[60] = 0; |
1213 |
lp->data[61] = 1; |
1214 |
|
1215 |
/* Server's IPv4 address: (giaddr) */ |
1216 |
memcpy(lp->data + 66, &net->gateway_ipv4_addr[0], 4); |
1217 |
|
1218 |
/* This is a Reply: */ |
1219 |
lp->data[42] = 0x02; |
1220 |
|
1221 |
snprintf(lp->data + 70+16+64, 8, "gxemul"); |
1222 |
|
1223 |
/* Recalculate IP header checksum: */ |
1224 |
net_ip_checksum(lp->data + 14, 10, 20); |
1225 |
|
1226 |
/* ... and the UDP checksum: */ |
1227 |
net_ip_tcp_checksum(lp->data + 34, 6, len - 34 - 8, |
1228 |
lp->data + 26, lp->data + 30, 1); |
1229 |
|
1230 |
|
1231 |
/* Debug dump: */ |
1232 |
packet = lp->data; |
1233 |
fatal("[ net: IPv4 DHCP REPLY: "); |
1234 |
for (i=0; i<14; i++) |
1235 |
fatal("%02x", packet[i]); |
1236 |
fatal("ver=%02x ", packet[14]); |
1237 |
fatal("tos=%02x ", packet[15]); |
1238 |
fatal("len=%02x%02x ", packet[16], packet[17]); |
1239 |
fatal("id=%02x%02x ", packet[18], packet[19]); |
1240 |
fatal("ofs=%02x%02x ", packet[20], packet[21]); |
1241 |
fatal("ttl=%02x ", packet[22]); |
1242 |
fatal("p=%02x ", packet[23]); |
1243 |
fatal("sum=%02x%02x ", packet[24], packet[25]); |
1244 |
fatal("src=%02x%02x%02x%02x ", |
1245 |
packet[26], packet[27], packet[28], packet[29]); |
1246 |
fatal("dst=%02x%02x%02x%02x ", |
1247 |
packet[30], packet[31], packet[32], packet[33]); |
1248 |
fatal("op=%02x ", packet[42]); |
1249 |
fatal("htype=%02x ", packet[43]); |
1250 |
fatal("hlen=%02x ", packet[44]); |
1251 |
fatal("hops=%02x ", packet[45]); |
1252 |
fatal("xid=%02x%02x%02x%02x ", packet[46], packet[47], |
1253 |
packet[48], packet[49]); |
1254 |
fatal("secs=%02x%02x ", packet[50], packet[51]); |
1255 |
fatal("flags=%02x%02x ", packet[52], packet[53]); |
1256 |
fatal("ciaddr=%02x%02x%02x%02x ", packet[54], packet[55], |
1257 |
packet[56], packet[57]); |
1258 |
fatal("yiaddr=%02x%02x%02x%02x ", packet[58], packet[59], |
1259 |
packet[60], packet[61]); |
1260 |
fatal("siaddr=%02x%02x%02x%02x ", packet[62], packet[63], |
1261 |
packet[64], packet[65]); |
1262 |
fatal("giaddr=%02x%02x%02x%02x ", packet[66], packet[67], |
1263 |
packet[68], packet[69]); |
1264 |
fatal("chaddr="); |
1265 |
for (i=70; i<70+16; i++) |
1266 |
fatal("%02x", packet[i]); |
1267 |
fatal(" ]\n"); |
1268 |
|
1269 |
#endif |
1270 |
} |
1271 |
|
1272 |
|
1273 |
/* |
1274 |
* net_ip_broadcast(): |
1275 |
* |
1276 |
* Handle an IP broadcast packet, coming from the emulated NIC. |
1277 |
* (This is usually a DHCP request, or similar.) |
1278 |
*/ |
1279 |
static void net_ip_broadcast(struct net *net, void *extra, |
1280 |
unsigned char *packet, int len) |
1281 |
{ |
1282 |
unsigned char *p = (void *) &net->netmask_ipv4; |
1283 |
uint32_t x, y; |
1284 |
int i, xl, warning = 0, match = 0; |
1285 |
|
1286 |
#if 0 |
1287 |
fatal("[ net: IP BROADCAST: "); |
1288 |
fatal("ver=%02x ", packet[14]); |
1289 |
fatal("tos=%02x ", packet[15]); |
1290 |
fatal("len=%02x%02x ", packet[16], packet[17]); |
1291 |
fatal("id=%02x%02x ", packet[18], packet[19]); |
1292 |
fatal("ofs=%02x%02x ", packet[20], packet[21]); |
1293 |
fatal("ttl=%02x ", packet[22]); |
1294 |
fatal("p=%02x ", packet[23]); |
1295 |
fatal("sum=%02x%02x ", packet[24], packet[25]); |
1296 |
fatal("src=%02x%02x%02x%02x ", |
1297 |
packet[26], packet[27], packet[28], packet[29]); |
1298 |
fatal("dst=%02x%02x%02x%02x ", |
1299 |
packet[30], packet[31], packet[32], packet[33]); |
1300 |
for (i=34; i<len; i++) |
1301 |
fatal("%02x", packet[i]); |
1302 |
fatal(" ]\n"); |
1303 |
#endif |
1304 |
|
1305 |
/* Check for 10.0.0.255 first, maybe some guest OSes think that |
1306 |
it's a /24 network, regardless of what it actually is. */ |
1307 |
y = (packet[30] << 24) + (packet[31] << 16) + |
1308 |
(packet[32] << 8) + packet[33]; |
1309 |
|
1310 |
x = (p[0] << 24) + (p[1] << 16) + (p[2] << 8) + p[3]; |
1311 |
/* Example: x = 10.0.0.0 */ |
1312 |
x |= 255; |
1313 |
|
1314 |
if (x == y) { |
1315 |
warning = 1; |
1316 |
match = 1; |
1317 |
} |
1318 |
|
1319 |
xl = 32 - net->netmask_ipv4_len; |
1320 |
x |= (1 << xl) - 1; |
1321 |
/* x = 10.255.255.255 */ |
1322 |
|
1323 |
if (x == y) |
1324 |
match = 1; |
1325 |
if (y == 0xffffffff) |
1326 |
match = 1; |
1327 |
|
1328 |
if (warning) |
1329 |
fatal("[ net_ip_broadcast(): warning: broadcast to " |
1330 |
"0x%08x, expecting broadcast to 0x%08x or " |
1331 |
"0xffffffff ]\n", y, x); |
1332 |
|
1333 |
/* Cut off overflowing tail data: */ |
1334 |
if (len > 14 + packet[16]*256 + packet[17]) |
1335 |
len = 14 + packet[16]*256 + packet[17]; |
1336 |
|
1337 |
/* Check for known packets: */ |
1338 |
if (packet[14] == 0x45 && /* IPv4 */ |
1339 |
packet[23] == 0x11 && /* UDP */ |
1340 |
packet[34] == 0 && packet[35] == 68 && /* DHCP client */ |
1341 |
packet[36] == 0 && packet[37] == 67) { /* DHCP server */ |
1342 |
net_ip_broadcast_dhcp(net, extra, packet, len); |
1343 |
return; |
1344 |
} |
1345 |
|
1346 |
/* Unknown packet: */ |
1347 |
fatal("[ net: UNIMPLEMENTED IP BROADCAST: "); |
1348 |
fatal("ver=%02x ", packet[14]); |
1349 |
fatal("tos=%02x ", packet[15]); |
1350 |
fatal("len=%02x%02x ", packet[16], packet[17]); |
1351 |
fatal("id=%02x%02x ", packet[18], packet[19]); |
1352 |
fatal("ofs=%02x%02x ", packet[20], packet[21]); |
1353 |
fatal("ttl=%02x ", packet[22]); |
1354 |
fatal("p=%02x ", packet[23]); |
1355 |
fatal("sum=%02x%02x ", packet[24], packet[25]); |
1356 |
fatal("src=%02x%02x%02x%02x ", |
1357 |
packet[26], packet[27], packet[28], packet[29]); |
1358 |
fatal("dst=%02x%02x%02x%02x ", |
1359 |
packet[30], packet[31], packet[32], packet[33]); |
1360 |
for (i=34; i<len; i++) |
1361 |
fatal("%02x", packet[i]); |
1362 |
fatal(" ]\n"); |
1363 |
} |
1364 |
|
1365 |
|
1366 |
/* |
1367 |
* net_arp(): |
1368 |
* |
1369 |
* Handle an ARP (or RARP) packet, coming from the emulated NIC. |
1370 |
* |
1371 |
* An ARP packet might look like this: |
1372 |
* |
1373 |
* ARP header: |
1374 |
* ARP hardware addr family: 0001 |
1375 |
* ARP protocol addr family: 0800 |
1376 |
* ARP addr lengths: 06 04 |
1377 |
* ARP request: 0001 |
1378 |
* ARP from: 112233445566 01020304 |
1379 |
* ARP to: 000000000000 01020301 |
1380 |
* |
1381 |
* An ARP request with a 'to' IP value of the gateway should cause an |
1382 |
* ARP response packet to be created. |
1383 |
* |
1384 |
* An ARP request with the same from and to IP addresses should be ignored. |
1385 |
* (This would be a host testing to see if there is an IP collision.) |
1386 |
*/ |
1387 |
static void net_arp(struct net *net, void *extra, |
1388 |
unsigned char *packet, int len, int reverse) |
1389 |
{ |
1390 |
int q; |
1391 |
int i; |
1392 |
|
1393 |
/* TODO: This debug dump assumes ethernet->IPv4 translation: */ |
1394 |
if (reverse) |
1395 |
debug("[ net: RARP: "); |
1396 |
else |
1397 |
debug("[ net: ARP: "); |
1398 |
for (i=0; i<2; i++) |
1399 |
debug("%02x", packet[i]); |
1400 |
debug(" "); |
1401 |
for (i=2; i<4; i++) |
1402 |
debug("%02x", packet[i]); |
1403 |
debug(" "); |
1404 |
debug("%02x", packet[4]); |
1405 |
debug(" "); |
1406 |
debug("%02x", packet[5]); |
1407 |
debug(" req="); |
1408 |
debug("%02x", packet[6]); /* Request type */ |
1409 |
debug("%02x", packet[7]); |
1410 |
debug(" from="); |
1411 |
for (i=8; i<18; i++) |
1412 |
debug("%02x", packet[i]); |
1413 |
debug(" to="); |
1414 |
for (i=18; i<28; i++) |
1415 |
debug("%02x", packet[i]); |
1416 |
debug(" ]\n"); |
1417 |
|
1418 |
if (packet[0] == 0x00 && packet[1] == 0x01 && |
1419 |
packet[2] == 0x08 && packet[3] == 0x00 && |
1420 |
packet[4] == 0x06 && packet[5] == 0x04) { |
1421 |
int r = (packet[6] << 8) + packet[7]; |
1422 |
struct ethernet_packet_link *lp; |
1423 |
|
1424 |
switch (r) { |
1425 |
case 1: /* Request */ |
1426 |
/* Only create a reply if this was meant for the |
1427 |
gateway: */ |
1428 |
if (memcmp(packet+24, net->gateway_ipv4_addr, 4) != 0) |
1429 |
break; |
1430 |
|
1431 |
lp = net_allocate_packet_link(net, extra, 60 + 14); |
1432 |
|
1433 |
/* Copy the old packet first: */ |
1434 |
memset(lp->data, 0, 60 + 14); |
1435 |
memcpy(lp->data + 14, packet, len); |
1436 |
|
1437 |
/* Add ethernet ARP header: */ |
1438 |
memcpy(lp->data + 0, lp->data + 8 + 14, 6); |
1439 |
memcpy(lp->data + 6, net->gateway_ethernet_addr, 6); |
1440 |
lp->data[12] = 0x08; lp->data[13] = 0x06; |
1441 |
|
1442 |
/* Address of the emulated machine: */ |
1443 |
memcpy(lp->data + 18 + 14, lp->data + 8 + 14, 10); |
1444 |
|
1445 |
/* Address of the gateway: */ |
1446 |
memcpy(lp->data + 8 + 14, net->gateway_ethernet_addr, |
1447 |
6); |
1448 |
memcpy(lp->data + 14 + 14, net->gateway_ipv4_addr, 4); |
1449 |
|
1450 |
/* This is a Reply: */ |
1451 |
lp->data[6 + 14] = 0x00; lp->data[7 + 14] = 0x02; |
1452 |
|
1453 |
break; |
1454 |
case 3: /* Reverse Request */ |
1455 |
lp = net_allocate_packet_link(net, extra, 60 + 14); |
1456 |
|
1457 |
/* Copy the old packet first: */ |
1458 |
memset(lp->data, 0, 60 + 14); |
1459 |
memcpy(lp->data + 14, packet, len); |
1460 |
|
1461 |
/* Add ethernet RARP header: */ |
1462 |
memcpy(lp->data + 0, packet + 8, 6); |
1463 |
memcpy(lp->data + 6, net->gateway_ethernet_addr, 6); |
1464 |
lp->data[12] = 0x80; lp->data[13] = 0x35; |
1465 |
|
1466 |
/* This is a RARP reply: */ |
1467 |
lp->data[6 + 14] = 0x00; lp->data[7 + 14] = 0x04; |
1468 |
|
1469 |
/* Address of the gateway: */ |
1470 |
memcpy(lp->data + 8 + 14, net->gateway_ethernet_addr, |
1471 |
6); |
1472 |
memcpy(lp->data + 14 + 14, net->gateway_ipv4_addr, 4); |
1473 |
|
1474 |
/* MAC address of emulated machine: */ |
1475 |
memcpy(lp->data + 18 + 14, packet + 8, 6); |
1476 |
|
1477 |
/* |
1478 |
* IP address of the emulated machine: Automagically |
1479 |
* generated from the MAC address. :-) |
1480 |
* |
1481 |
* packet+8 points to the client's mac address, |
1482 |
* for example 10:20:30:00:00:z0, where z is 0..15. |
1483 |
* 10:20:30:00:00:10 results in 10.0.0.1. |
1484 |
*/ |
1485 |
/* q = (packet[8 + 3]) >> 4; */ |
1486 |
/* q = q*15 + ((packet[8 + 4]) >> 4); */ |
1487 |
q = (packet[8 + 5]) >> 4; |
1488 |
lp->data[24 + 14] = 10; |
1489 |
lp->data[25 + 14] = 0; |
1490 |
lp->data[26 + 14] = 0; |
1491 |
lp->data[27 + 14] = q; |
1492 |
break; |
1493 |
case 2: /* Reply */ |
1494 |
case 4: /* Reverse Reply */ |
1495 |
default: |
1496 |
fatal("[ net: ARP: UNIMPLEMENTED request type " |
1497 |
"0x%04x ]\n", r); |
1498 |
} |
1499 |
} else { |
1500 |
fatal("[ net: ARP: UNIMPLEMENTED arp packet type: "); |
1501 |
for (i=0; i<len; i++) |
1502 |
fatal("%02x", packet[i]); |
1503 |
fatal(" ]\n"); |
1504 |
} |
1505 |
} |
1506 |
|
1507 |
|
1508 |
/* |
1509 |
* net_ethernet_rx_avail(): |
1510 |
* |
1511 |
* Return 1 if there is a packet available for this 'extra' pointer, otherwise |
1512 |
* return 0. |
1513 |
* |
1514 |
* Appart from actually checking for incoming packets from the outside world, |
1515 |
* this function basically works like net_ethernet_rx() but it only receives |
1516 |
* a return value telling us whether there is a packet or not, we don't |
1517 |
* actually get the packet. |
1518 |
*/ |
1519 |
int net_ethernet_rx_avail(struct net *net, void *extra) |
1520 |
{ |
1521 |
int received_packets_this_tick = 0; |
1522 |
int max_packets_this_tick = 200; |
1523 |
int con_id; |
1524 |
|
1525 |
if (net == NULL) |
1526 |
return 0; |
1527 |
|
1528 |
/* |
1529 |
* If the network is distributed across multiple emulator processes, |
1530 |
* then receive incoming packets from those processes. |
1531 |
*/ |
1532 |
if (net->local_port != 0) { |
1533 |
struct sockaddr_in si; |
1534 |
socklen_t si_len = sizeof(si); |
1535 |
int res, i; |
1536 |
unsigned char buf[60000]; |
1537 |
|
1538 |
if ((res = recvfrom(net->local_port_socket, buf, sizeof(buf), 0, |
1539 |
(struct sockaddr *)&si, &si_len)) != -1) { |
1540 |
/* fatal("DISTRIBUTED packet, %i bytes from %s:%d\n", |
1541 |
res, inet_ntoa(si.sin_addr), ntohs(si.sin_port)); */ |
1542 |
for (i=0; i<net->n_nics; i++) { |
1543 |
struct ethernet_packet_link *lp; |
1544 |
lp = net_allocate_packet_link(net, |
1545 |
net->nic_extra[i], res); |
1546 |
memcpy(lp->data, buf, res); |
1547 |
} |
1548 |
} |
1549 |
} |
1550 |
|
1551 |
/* |
1552 |
* UDP: |
1553 |
*/ |
1554 |
for (con_id=0; con_id<MAX_UDP_CONNECTIONS; con_id++) { |
1555 |
ssize_t res; |
1556 |
unsigned char buf[66000]; |
1557 |
unsigned char udp_data[66008]; |
1558 |
struct sockaddr_in from; |
1559 |
socklen_t from_len = sizeof(from); |
1560 |
int ip_len, udp_len; |
1561 |
struct ethernet_packet_link *lp; |
1562 |
int max_per_packet; |
1563 |
int bytes_converted = 0; |
1564 |
int this_packets_data_length; |
1565 |
int fragment_ofs = 0; |
1566 |
|
1567 |
if (received_packets_this_tick > max_packets_this_tick) |
1568 |
break; |
1569 |
|
1570 |
if (!net->udp_connections[con_id].in_use) |
1571 |
continue; |
1572 |
|
1573 |
if (net->udp_connections[con_id].socket < 0) { |
1574 |
fatal("INTERNAL ERROR in net.c, udp socket < 0 " |
1575 |
"but in use?\n"); |
1576 |
continue; |
1577 |
} |
1578 |
|
1579 |
res = recvfrom(net->udp_connections[con_id].socket, buf, |
1580 |
sizeof(buf), 0, (struct sockaddr *)&from, &from_len); |
1581 |
|
1582 |
/* No more incoming UDP on this connection? */ |
1583 |
if (res < 0) |
1584 |
continue; |
1585 |
|
1586 |
net->timestamp ++; |
1587 |
net->udp_connections[con_id].last_used_timestamp = |
1588 |
net->timestamp; |
1589 |
|
1590 |
net->udp_connections[con_id].udp_id ++; |
1591 |
|
1592 |
/* |
1593 |
* Special case for the nameserver: If a UDP packet is |
1594 |
* received from the nameserver (if the nameserver's IP is |
1595 |
* known), fake it so that it comes from the gateway instead. |
1596 |
*/ |
1597 |
if (net->udp_connections[con_id].fake_ns) |
1598 |
memcpy(((unsigned char *)(&from))+4, |
1599 |
&net->gateway_ipv4_addr[0], 4); |
1600 |
|
1601 |
/* |
1602 |
* We now have a UDP packet of size 'res' which we need |
1603 |
* turn into one or more ethernet packets for the emulated |
1604 |
* operating system. Ethernet packets are at most 1518 |
1605 |
* bytes long. With some margin, that means we can have |
1606 |
* about 1500 bytes per packet. |
1607 |
* |
1608 |
* Ethernet = 14 bytes |
1609 |
* IP = 20 bytes |
1610 |
* (UDP = 8 bytes + data) |
1611 |
* |
1612 |
* So data can be at most max_per_packet - 34. For UDP |
1613 |
* fragments, each multiple should (?) be a multiple of |
1614 |
* 8 bytes, except the last which doesn't have any such |
1615 |
* restriction. |
1616 |
*/ |
1617 |
max_per_packet = 1500; |
1618 |
|
1619 |
/* UDP: */ |
1620 |
udp_len = res + 8; |
1621 |
/* from[2..3] = outside_udp_port */ |
1622 |
udp_data[0] = ((unsigned char *)&from)[2]; |
1623 |
udp_data[1] = ((unsigned char *)&from)[3]; |
1624 |
udp_data[2] = (net->udp_connections[con_id]. |
1625 |
inside_udp_port >> 8) & 0xff; |
1626 |
udp_data[3] = net->udp_connections[con_id]. |
1627 |
inside_udp_port & 0xff; |
1628 |
udp_data[4] = udp_len >> 8; |
1629 |
udp_data[5] = udp_len & 0xff; |
1630 |
udp_data[6] = 0; |
1631 |
udp_data[7] = 0; |
1632 |
memcpy(udp_data + 8, buf, res); |
1633 |
/* |
1634 |
* TODO: UDP checksum, if necessary. At least NetBSD |
1635 |
* and OpenBSD accept UDP packets with 0x0000 in the |
1636 |
* checksum field anyway. |
1637 |
*/ |
1638 |
|
1639 |
while (bytes_converted < udp_len) { |
1640 |
this_packets_data_length = udp_len - bytes_converted; |
1641 |
|
1642 |
/* Do we need to fragment? */ |
1643 |
if (this_packets_data_length > max_per_packet-34) { |
1644 |
this_packets_data_length = |
1645 |
max_per_packet - 34; |
1646 |
while (this_packets_data_length & 7) |
1647 |
this_packets_data_length --; |
1648 |
} |
1649 |
|
1650 |
ip_len = 20 + this_packets_data_length; |
1651 |
|
1652 |
lp = net_allocate_packet_link(net, extra, |
1653 |
14 + 20 + this_packets_data_length); |
1654 |
|
1655 |
/* Ethernet header: */ |
1656 |
memcpy(lp->data + 0, net->udp_connections[con_id]. |
1657 |
ethernet_address, 6); |
1658 |
memcpy(lp->data + 6, net->gateway_ethernet_addr, 6); |
1659 |
lp->data[12] = 0x08; /* IP = 0x0800 */ |
1660 |
lp->data[13] = 0x00; |
1661 |
|
1662 |
/* IP header: */ |
1663 |
lp->data[14] = 0x45; /* ver */ |
1664 |
lp->data[15] = 0x00; /* tos */ |
1665 |
lp->data[16] = ip_len >> 8; |
1666 |
lp->data[17] = ip_len & 0xff; |
1667 |
lp->data[18] = net->udp_connections[con_id].udp_id >> 8; |
1668 |
lp->data[19] = net->udp_connections[con_id].udp_id |
1669 |
& 0xff; |
1670 |
lp->data[20] = (fragment_ofs >> 8); |
1671 |
if (bytes_converted + this_packets_data_length |
1672 |
< udp_len) |
1673 |
lp->data[20] |= 0x20; /* More fragments */ |
1674 |
lp->data[21] = fragment_ofs & 0xff; |
1675 |
lp->data[22] = 0x40; /* ttl */ |
1676 |
lp->data[23] = 17; /* p = UDP */ |
1677 |
lp->data[26] = ((unsigned char *)&from)[4]; |
1678 |
lp->data[27] = ((unsigned char *)&from)[5]; |
1679 |
lp->data[28] = ((unsigned char *)&from)[6]; |
1680 |
lp->data[29] = ((unsigned char *)&from)[7]; |
1681 |
memcpy(lp->data + 30, net->udp_connections[con_id]. |
1682 |
inside_ip_address, 4); |
1683 |
net_ip_checksum(lp->data + 14, 10, 20); |
1684 |
|
1685 |
memcpy(lp->data+34, udp_data + bytes_converted, |
1686 |
this_packets_data_length); |
1687 |
|
1688 |
bytes_converted += this_packets_data_length; |
1689 |
fragment_ofs = bytes_converted / 8; |
1690 |
|
1691 |
received_packets_this_tick ++; |
1692 |
} |
1693 |
|
1694 |
/* This makes sure we check this connection AGAIN |
1695 |
for more incoming UDP packets, before moving to the |
1696 |
next connection: */ |
1697 |
con_id --; |
1698 |
} |
1699 |
|
1700 |
/* |
1701 |
* TCP: |
1702 |
*/ |
1703 |
for (con_id=0; con_id<MAX_TCP_CONNECTIONS; con_id++) { |
1704 |
unsigned char buf[66000]; |
1705 |
ssize_t res, res2; |
1706 |
fd_set rfds; |
1707 |
struct timeval tv; |
1708 |
|
1709 |
if (received_packets_this_tick > max_packets_this_tick) |
1710 |
break; |
1711 |
|
1712 |
if (!net->tcp_connections[con_id].in_use) |
1713 |
continue; |
1714 |
|
1715 |
if (net->tcp_connections[con_id].socket < 0) { |
1716 |
fatal("INTERNAL ERROR in net.c, tcp socket < 0" |
1717 |
" but in use?\n"); |
1718 |
continue; |
1719 |
} |
1720 |
|
1721 |
if (net->tcp_connections[con_id].incoming_buf == NULL) { |
1722 |
net->tcp_connections[con_id].incoming_buf = |
1723 |
malloc(TCP_INCOMING_BUF_LEN); |
1724 |
if (net->tcp_connections[con_id].incoming_buf == NULL) { |
1725 |
printf("out of memory allocating " |
1726 |
"incoming_buf for con_id %i\n", con_id); |
1727 |
exit(1); |
1728 |
} |
1729 |
} |
1730 |
|
1731 |
if (net->tcp_connections[con_id].state >= |
1732 |
TCP_OUTSIDE_DISCONNECTED) |
1733 |
continue; |
1734 |
|
1735 |
/* Is the socket available for output? */ |
1736 |
FD_ZERO(&rfds); /* write */ |
1737 |
FD_SET(net->tcp_connections[con_id].socket, &rfds); |
1738 |
tv.tv_sec = tv.tv_usec = 0; |
1739 |
errno = 0; |
1740 |
res = select(net->tcp_connections[con_id].socket+1, |
1741 |
NULL, &rfds, NULL, &tv); |
1742 |
|
1743 |
if (errno == ECONNREFUSED) { |
1744 |
fatal("[ ECONNREFUSED: TODO ]\n"); |
1745 |
net->tcp_connections[con_id].state = |
1746 |
TCP_OUTSIDE_DISCONNECTED; |
1747 |
fatal("CHANGING TO TCP_OUTSIDE_DISCONNECTED " |
1748 |
"(refused connection)\n"); |
1749 |
continue; |
1750 |
} |
1751 |
|
1752 |
if (errno == ETIMEDOUT) { |
1753 |
fatal("[ ETIMEDOUT: TODO ]\n"); |
1754 |
/* TODO */ |
1755 |
net->tcp_connections[con_id].state = |
1756 |
TCP_OUTSIDE_DISCONNECTED; |
1757 |
fatal("CHANGING TO TCP_OUTSIDE_DISCONNECTED " |
1758 |
"(timeout)\n"); |
1759 |
continue; |
1760 |
} |
1761 |
|
1762 |
if (net->tcp_connections[con_id].state == |
1763 |
TCP_OUTSIDE_TRYINGTOCONNECT && res > 0) { |
1764 |
net->tcp_connections[con_id].state = |
1765 |
TCP_OUTSIDE_CONNECTED; |
1766 |
debug("CHANGING TO TCP_OUTSIDE_CONNECTED\n"); |
1767 |
net_ip_tcp_connectionreply(net, extra, con_id, 1, |
1768 |
NULL, 0, 0); |
1769 |
} |
1770 |
|
1771 |
if (net->tcp_connections[con_id].state == |
1772 |
TCP_OUTSIDE_CONNECTED && res < 1) { |
1773 |
continue; |
1774 |
} |
1775 |
|
1776 |
/* |
1777 |
* Does this connection have unacknowledged data? Then, if |
1778 |
* enough number of rounds have passed, try to resend it using |
1779 |
* the old value of seqnr. |
1780 |
*/ |
1781 |
if (net->tcp_connections[con_id].incoming_buf_len != 0) { |
1782 |
net->tcp_connections[con_id].incoming_buf_rounds ++; |
1783 |
if (net->tcp_connections[con_id].incoming_buf_rounds > |
1784 |
10000) { |
1785 |
debug(" at seqnr %u but backing back to %u," |
1786 |
" resending %i bytes\n", |
1787 |
net->tcp_connections[con_id].outside_seqnr, |
1788 |
net->tcp_connections[con_id]. |
1789 |
incoming_buf_seqnr, |
1790 |
net->tcp_connections[con_id]. |
1791 |
incoming_buf_len); |
1792 |
|
1793 |
net->tcp_connections[con_id]. |
1794 |
incoming_buf_rounds = 0; |
1795 |
net->tcp_connections[con_id].outside_seqnr = |
1796 |
net->tcp_connections[con_id]. |
1797 |
incoming_buf_seqnr; |
1798 |
|
1799 |
net_ip_tcp_connectionreply(net, extra, con_id, |
1800 |
0, net->tcp_connections[con_id]. |
1801 |
incoming_buf, |
1802 |
net->tcp_connections[con_id]. |
1803 |
incoming_buf_len, 0); |
1804 |
} |
1805 |
continue; |
1806 |
} |
1807 |
|
1808 |
/* Don't receive unless the guest OS is ready! */ |
1809 |
if (((int32_t)net->tcp_connections[con_id].outside_seqnr - |
1810 |
(int32_t)net->tcp_connections[con_id].inside_acknr) > 0) { |
1811 |
/* fatal("YOYO 1! outside_seqnr - inside_acknr = %i\n", |
1812 |
net->tcp_connections[con_id].outside_seqnr - |
1813 |
net->tcp_connections[con_id].inside_acknr); */ |
1814 |
continue; |
1815 |
} |
1816 |
|
1817 |
/* Is there incoming data available on the socket? */ |
1818 |
FD_ZERO(&rfds); /* read */ |
1819 |
FD_SET(net->tcp_connections[con_id].socket, &rfds); |
1820 |
tv.tv_sec = tv.tv_usec = 0; |
1821 |
res2 = select(net->tcp_connections[con_id].socket+1, &rfds, |
1822 |
NULL, NULL, &tv); |
1823 |
|
1824 |
/* No more incoming TCP data on this connection? */ |
1825 |
if (res2 < 1) |
1826 |
continue; |
1827 |
|
1828 |
res = read(net->tcp_connections[con_id].socket, buf, 1400); |
1829 |
if (res > 0) { |
1830 |
/* debug("\n -{- %lli -}-\n", (long long)res); */ |
1831 |
net->tcp_connections[con_id].incoming_buf_len = res; |
1832 |
net->tcp_connections[con_id].incoming_buf_rounds = 0; |
1833 |
net->tcp_connections[con_id].incoming_buf_seqnr = |
1834 |
net->tcp_connections[con_id].outside_seqnr; |
1835 |
debug(" putting %i bytes (seqnr %u) in the incoming " |
1836 |
"buf\n", res, net->tcp_connections[con_id]. |
1837 |
incoming_buf_seqnr); |
1838 |
memcpy(net->tcp_connections[con_id].incoming_buf, |
1839 |
buf, res); |
1840 |
|
1841 |
net_ip_tcp_connectionreply(net, extra, con_id, 0, |
1842 |
buf, res, 0); |
1843 |
} else if (res == 0) { |
1844 |
net->tcp_connections[con_id].state = |
1845 |
TCP_OUTSIDE_DISCONNECTED; |
1846 |
debug("CHANGING TO TCP_OUTSIDE_DISCONNECTED, read" |
1847 |
" res=0\n"); |
1848 |
net_ip_tcp_connectionreply(net, extra, con_id, 0, |
1849 |
NULL, 0, 0); |
1850 |
} else { |
1851 |
net->tcp_connections[con_id].state = |
1852 |
TCP_OUTSIDE_DISCONNECTED; |
1853 |
fatal("CHANGING TO TCP_OUTSIDE_DISCONNECTED, " |
1854 |
"read res<=0, errno = %i\n", errno); |
1855 |
net_ip_tcp_connectionreply(net, extra, con_id, 0, |
1856 |
NULL, 0, 0); |
1857 |
} |
1858 |
|
1859 |
net->timestamp ++; |
1860 |
net->tcp_connections[con_id].last_used_timestamp = |
1861 |
net->timestamp; |
1862 |
} |
1863 |
|
1864 |
return net_ethernet_rx(net, extra, NULL, NULL); |
1865 |
} |
1866 |
|
1867 |
|
1868 |
/* |
1869 |
* net_ethernet_rx(): |
1870 |
* |
1871 |
* Receive an ethernet packet. (This means handing over an already prepared |
1872 |
* packet from this module (net.c) to a specific ethernet controller device.) |
1873 |
* |
1874 |
* Return value is 1 if there was a packet available. *packetp and *lenp |
1875 |
* will be set to the packet's data pointer and length, respectively, and |
1876 |
* the packet will be removed from the linked list). If there was no packet |
1877 |
* available, 0 is returned. |
1878 |
* |
1879 |
* If packetp is NULL, then the search is aborted as soon as a packet with |
1880 |
* the correct 'extra' field is found, and a 1 is returned, but as packetp |
1881 |
* is NULL we can't return the actual packet. (This is the internal form |
1882 |
* if net_ethernet_rx_avail().) |
1883 |
*/ |
1884 |
int net_ethernet_rx(struct net *net, void *extra, |
1885 |
unsigned char **packetp, int *lenp) |
1886 |
{ |
1887 |
struct ethernet_packet_link *lp, *prev; |
1888 |
|
1889 |
if (net == NULL) |
1890 |
return 0; |
1891 |
|
1892 |
/* Find the first packet which has the right 'extra' field. */ |
1893 |
|
1894 |
lp = net->first_ethernet_packet; |
1895 |
prev = NULL; |
1896 |
while (lp != NULL) { |
1897 |
if (lp->extra == extra) { |
1898 |
/* We found a packet for this controller! */ |
1899 |
if (packetp == NULL || lenp == NULL) |
1900 |
return 1; |
1901 |
|
1902 |
/* Let's return it: */ |
1903 |
(*packetp) = lp->data; |
1904 |
(*lenp) = lp->len; |
1905 |
|
1906 |
/* Remove this link from the linked list: */ |
1907 |
if (prev == NULL) |
1908 |
net->first_ethernet_packet = lp->next; |
1909 |
else |
1910 |
prev->next = lp->next; |
1911 |
|
1912 |
if (lp->next == NULL) |
1913 |
net->last_ethernet_packet = prev; |
1914 |
else |
1915 |
lp->next->prev = prev; |
1916 |
|
1917 |
free(lp); |
1918 |
|
1919 |
/* ... and return successfully: */ |
1920 |
return 1; |
1921 |
} |
1922 |
|
1923 |
prev = lp; |
1924 |
lp = lp->next; |
1925 |
} |
1926 |
|
1927 |
/* No packet found. :-( */ |
1928 |
return 0; |
1929 |
} |
1930 |
|
1931 |
|
1932 |
/* |
1933 |
* send_udp(): |
1934 |
* |
1935 |
* Send a simple UDP packet to some other (real) host. Used for distributed |
1936 |
* network simulations. |
1937 |
*/ |
1938 |
void send_udp(struct in_addr *addrp, int portnr, unsigned char *packet, |
1939 |
size_t len) |
1940 |
{ |
1941 |
int s; |
1942 |
struct sockaddr_in si; |
1943 |
|
1944 |
s = socket(AF_INET, SOCK_DGRAM, 0); |
1945 |
if (s < 0) { |
1946 |
perror("send_udp(): socket"); |
1947 |
return; |
1948 |
} |
1949 |
|
1950 |
/* fatal("send_udp(): sending to port %i\n", portnr); */ |
1951 |
|
1952 |
si.sin_family = AF_INET; |
1953 |
si.sin_addr = *addrp; |
1954 |
si.sin_port = htons(portnr); |
1955 |
|
1956 |
if (sendto(s, packet, len, 0, (struct sockaddr *)&si, |
1957 |
sizeof(si)) != (ssize_t)len) { |
1958 |
perror("send_udp(): sendto"); |
1959 |
} |
1960 |
|
1961 |
close(s); |
1962 |
} |
1963 |
|
1964 |
|
1965 |
/* |
1966 |
* net_ethernet_tx(): |
1967 |
* |
1968 |
* Transmit an ethernet packet, as seen from the emulated ethernet controller. |
1969 |
* If the packet can be handled here, it will not necessarily be transmitted |
1970 |
* to the outside world. |
1971 |
*/ |
1972 |
void net_ethernet_tx(struct net *net, void *extra, |
1973 |
unsigned char *packet, int len) |
1974 |
{ |
1975 |
int i, n; |
1976 |
|
1977 |
if (net == NULL) |
1978 |
return; |
1979 |
|
1980 |
/* Drop too small packets: */ |
1981 |
if (len < 20) |
1982 |
return; |
1983 |
|
1984 |
/* |
1985 |
* Copy this packet to all other NICs on this network: |
1986 |
*/ |
1987 |
if (extra != NULL && net->n_nics > 0) { |
1988 |
for (i=0; i<net->n_nics; i++) |
1989 |
if (extra != net->nic_extra[i]) { |
1990 |
struct ethernet_packet_link *lp; |
1991 |
lp = net_allocate_packet_link(net, |
1992 |
net->nic_extra[i], len); |
1993 |
|
1994 |
/* Copy the entire packet: */ |
1995 |
memcpy(lp->data, packet, len); |
1996 |
} |
1997 |
} |
1998 |
|
1999 |
/* |
2000 |
* If this network is distributed across multiple emulator processes, |
2001 |
* then transmit the packet to those other processes. |
2002 |
*/ |
2003 |
if (net->remote_nets != NULL) { |
2004 |
struct remote_net *rnp = net->remote_nets; |
2005 |
while (rnp != NULL) { |
2006 |
send_udp(&rnp->ipv4_addr, rnp->portnr, packet, len); |
2007 |
rnp = rnp->next; |
2008 |
} |
2009 |
} |
2010 |
|
2011 |
/* Drop packets that are not destined for the gateway: */ |
2012 |
if (memcmp(packet, net->gateway_ethernet_addr, 6) != 0 |
2013 |
&& packet[0] != 0xff && packet[0] != 0x00) |
2014 |
return; |
2015 |
|
2016 |
/* |
2017 |
* The code below simulates the behaviour of a "NAT"-style |
2018 |
* gateway. |
2019 |
*/ |
2020 |
#if 0 |
2021 |
fatal("[ net: ethernet: "); |
2022 |
for (i=0; i<6; i++) fatal("%02x", packet[i]); fatal(" "); |
2023 |
for (i=6; i<12; i++) fatal("%02x", packet[i]); fatal(" "); |
2024 |
for (i=12; i<14; i++) fatal("%02x", packet[i]); fatal(" "); |
2025 |
for (i=14; i<len; i++) fatal("%02x", packet[i]); fatal(" ]\n"); |
2026 |
#endif |
2027 |
|
2028 |
/* Sprite: */ |
2029 |
if (packet[12] == 0x05 && packet[13] == 0x00) { |
2030 |
/* TODO. */ |
2031 |
fatal("[ net: TX: UNIMPLEMENTED Sprite packet ]\n"); |
2032 |
return; |
2033 |
} |
2034 |
|
2035 |
/* IP: */ |
2036 |
if (packet[12] == 0x08 && packet[13] == 0x00) { |
2037 |
/* Routed via the gateway? */ |
2038 |
if (memcmp(packet+0, net->gateway_ethernet_addr, 6) == 0) { |
2039 |
net_ip(net, extra, packet, len); |
2040 |
return; |
2041 |
} |
2042 |
|
2043 |
/* Broadcast? (DHCP does this.) */ |
2044 |
n = 0; |
2045 |
for (i=0; i<6; i++) |
2046 |
if (packet[i] == 0xff) |
2047 |
n++; |
2048 |
if (n == 6) { |
2049 |
net_ip_broadcast(net, extra, packet, len); |
2050 |
return; |
2051 |
} |
2052 |
|
2053 |
if (net->n_nics < 2) { |
2054 |
fatal("[ net: TX: IP packet not for gateway, " |
2055 |
"and not broadcast: "); |
2056 |
for (i=0; i<14; i++) |
2057 |
fatal("%02x", packet[i]); |
2058 |
fatal(" ]\n"); |
2059 |
} |
2060 |
return; |
2061 |
} |
2062 |
|
2063 |
/* ARP: */ |
2064 |
if (packet[12] == 0x08 && packet[13] == 0x06) { |
2065 |
if (len != 42 && len != 60) |
2066 |
fatal("[ net_ethernet_tx: WARNING! unusual " |
2067 |
"ARP len (%i) ]\n", len); |
2068 |
net_arp(net, extra, packet + 14, len - 14, 0); |
2069 |
return; |
2070 |
} |
2071 |
|
2072 |
/* RARP: */ |
2073 |
if (packet[12] == 0x80 && packet[13] == 0x35) { |
2074 |
net_arp(net, extra, packet + 14, len - 14, 1); |
2075 |
return; |
2076 |
} |
2077 |
|
2078 |
/* IPv6: */ |
2079 |
if (packet[12] == 0x86 && packet[13] == 0xdd) { |
2080 |
/* TODO. */ |
2081 |
fatal("[ net: TX: UNIMPLEMENTED IPv6 packet ]\n"); |
2082 |
return; |
2083 |
} |
2084 |
|
2085 |
fatal("[ net: TX: UNIMPLEMENTED ethernet packet type 0x%02x%02x! ]\n", |
2086 |
packet[12], packet[13]); |
2087 |
} |
2088 |
|
2089 |
|
2090 |
/* |
2091 |
* parse_resolvconf(): |
2092 |
* |
2093 |
* This function parses "/etc/resolv.conf" to figure out the nameserver |
2094 |
* and domain used by the host. |
2095 |
*/ |
2096 |
static void parse_resolvconf(struct net *net) |
2097 |
{ |
2098 |
FILE *f; |
2099 |
char buf[8000]; |
2100 |
size_t len; |
2101 |
int res; |
2102 |
unsigned int i, start; |
2103 |
|
2104 |
/* |
2105 |
* This is a very ugly hack, which tries to figure out which |
2106 |
* nameserver the host uses by looking for the string 'nameserver' |
2107 |
* in /etc/resolv.conf. |
2108 |
* |
2109 |
* This can later on be used for DHCP autoconfiguration. (TODO) |
2110 |
* |
2111 |
* TODO: This is hardcoded to use /etc/resolv.conf. Not all |
2112 |
* operating systems use that filename. |
2113 |
* |
2114 |
* TODO: This is hardcoded for AF_INET (that is, IPv4). |
2115 |
* |
2116 |
* TODO: This assumes that the first nameserver listed is the |
2117 |
* one to use. |
2118 |
*/ |
2119 |
f = fopen("/etc/resolv.conf", "r"); |
2120 |
if (f == NULL) |
2121 |
return; |
2122 |
|
2123 |
/* TODO: get rid of the hardcoded values */ |
2124 |
memset(buf, 0, sizeof(buf)); |
2125 |
len = fread(buf, 1, sizeof(buf) - 100, f); |
2126 |
fclose(f); |
2127 |
buf[sizeof(buf) - 1] = '\0'; |
2128 |
|
2129 |
for (i=0; i<len; i++) |
2130 |
if (strncmp(buf+i, "nameserver", 10) == 0) { |
2131 |
char *p; |
2132 |
|
2133 |
/* |
2134 |
* "nameserver" (1 or more whitespace) |
2135 |
* "x.y.z.w" (non-digit) |
2136 |
*/ |
2137 |
|
2138 |
/* debug("found nameserver at offset %i\n", i); */ |
2139 |
i += 10; |
2140 |
while (i<len && (buf[i]==' ' || buf[i]=='\t')) |
2141 |
i++; |
2142 |
if (i >= len) |
2143 |
break; |
2144 |
start = i; |
2145 |
|
2146 |
p = buf+start; |
2147 |
while ((*p >= '0' && *p <= '9') || *p == '.') |
2148 |
p++; |
2149 |
*p = '\0'; |
2150 |
|
2151 |
#ifdef HAVE_INET_PTON |
2152 |
res = inet_pton(AF_INET, buf + start, |
2153 |
&net->nameserver_ipv4); |
2154 |
#else |
2155 |
res = inet_aton(buf + start, &net->nameserver_ipv4); |
2156 |
#endif |
2157 |
if (res < 1) |
2158 |
break; |
2159 |
|
2160 |
net->nameserver_known = 1; |
2161 |
break; |
2162 |
} |
2163 |
|
2164 |
for (i=0; i<len; i++) |
2165 |
if (strncmp(buf+i, "domain", 6) == 0) { |
2166 |
/* "domain" (1 or more whitespace) domain_name */ |
2167 |
i += 6; |
2168 |
while (i<len && (buf[i]==' ' || buf[i]=='\t')) |
2169 |
i++; |
2170 |
if (i >= len) |
2171 |
break; |
2172 |
|
2173 |
start = i; |
2174 |
while (i<len && buf[i]!='\n' && buf[i]!='\r') |
2175 |
i++; |
2176 |
if (i < len) |
2177 |
buf[i] = '\0'; |
2178 |
/* fatal("DOMAIN='%s'\n", buf + start); */ |
2179 |
net->domain_name = strdup(buf + start); |
2180 |
break; |
2181 |
} |
2182 |
} |
2183 |
|
2184 |
|
2185 |
/* |
2186 |
* net_add_nic(): |
2187 |
* |
2188 |
* Add a NIC to a network. (All NICs on a network will see each other's |
2189 |
* packets.) |
2190 |
*/ |
2191 |
void net_add_nic(struct net *net, void *extra, unsigned char *macaddr) |
2192 |
{ |
2193 |
if (net == NULL) |
2194 |
return; |
2195 |
|
2196 |
if (extra == NULL) { |
2197 |
fprintf(stderr, "net_add_nic(): extra = NULL\n"); |
2198 |
exit(1); |
2199 |
} |
2200 |
|
2201 |
net->n_nics ++; |
2202 |
net->nic_extra = realloc(net->nic_extra, sizeof(void *) |
2203 |
* net->n_nics); |
2204 |
if (net->nic_extra == NULL) { |
2205 |
fprintf(stderr, "net_add_nic(): out of memory\n"); |
2206 |
exit(1); |
2207 |
} |
2208 |
|
2209 |
net->nic_extra[net->n_nics - 1] = extra; |
2210 |
} |
2211 |
|
2212 |
|
2213 |
/* |
2214 |
* net_gateway_init(): |
2215 |
* |
2216 |
* This function creates a "gateway" machine (for example at IPv4 address |
2217 |
* 10.0.0.254, if the net is 10.0.0.0/8), which acts as a gateway/router/ |
2218 |
* nameserver etc. |
2219 |
*/ |
2220 |
static void net_gateway_init(struct net *net) |
2221 |
{ |
2222 |
unsigned char *p = (void *) &net->netmask_ipv4; |
2223 |
uint32_t x; |
2224 |
int xl; |
2225 |
|
2226 |
x = (p[0] << 24) + (p[1] << 16) + (p[2] << 8) + p[3]; |
2227 |
xl = 32 - net->netmask_ipv4_len; |
2228 |
if (xl > 8) |
2229 |
xl = 8; |
2230 |
x |= ((1 << xl) - 1) & ~1; |
2231 |
|
2232 |
net->gateway_ipv4_addr[0] = x >> 24; |
2233 |
net->gateway_ipv4_addr[1] = x >> 16; |
2234 |
net->gateway_ipv4_addr[2] = x >> 8; |
2235 |
net->gateway_ipv4_addr[3] = x; |
2236 |
|
2237 |
net->gateway_ethernet_addr[0] = 0x60; |
2238 |
net->gateway_ethernet_addr[1] = 0x50; |
2239 |
net->gateway_ethernet_addr[2] = 0x40; |
2240 |
net->gateway_ethernet_addr[3] = 0x30; |
2241 |
net->gateway_ethernet_addr[4] = 0x20; |
2242 |
net->gateway_ethernet_addr[5] = 0x10; |
2243 |
} |
2244 |
|
2245 |
|
2246 |
/* |
2247 |
* net_dumpinfo(): |
2248 |
* |
2249 |
* Called from the debugger's "machine" command, to print some info about |
2250 |
* a network. |
2251 |
*/ |
2252 |
void net_dumpinfo(struct net *net) |
2253 |
{ |
2254 |
int iadd = DEBUG_INDENTATION; |
2255 |
struct remote_net *rnp; |
2256 |
|
2257 |
debug("net: simulating "); |
2258 |
|
2259 |
net_debugaddr(&net->netmask_ipv4, ADDR_IPV4); |
2260 |
debug("/%i", net->netmask_ipv4_len); |
2261 |
|
2262 |
debug(" (max outgoing: TCP=%i, UDP=%i)\n", |
2263 |
MAX_TCP_CONNECTIONS, MAX_UDP_CONNECTIONS); |
2264 |
|
2265 |
debug_indentation(iadd); |
2266 |
|
2267 |
debug("simulated gateway: "); |
2268 |
net_debugaddr(&net->gateway_ipv4_addr, ADDR_IPV4); |
2269 |
debug(" ("); |
2270 |
net_debugaddr(&net->gateway_ethernet_addr, ADDR_ETHERNET); |
2271 |
debug(")\n"); |
2272 |
|
2273 |
debug_indentation(iadd); |
2274 |
if (!net->nameserver_known) { |
2275 |
debug("(could not determine nameserver)"); |
2276 |
} else { |
2277 |
debug("using nameserver "); |
2278 |
net_debugaddr(&net->nameserver_ipv4, ADDR_IPV4); |
2279 |
} |
2280 |
if (net->domain_name != NULL && net->domain_name[0]) |
2281 |
debug(", domain \"%s\"", net->domain_name); |
2282 |
debug("\n"); |
2283 |
debug_indentation(-iadd); |
2284 |
|
2285 |
rnp = net->remote_nets; |
2286 |
if (net->local_port != 0) |
2287 |
debug("distributed network: local port = %i\n", |
2288 |
net->local_port); |
2289 |
debug_indentation(iadd); |
2290 |
while (rnp != NULL) { |
2291 |
debug("remote \"%s\": ", rnp->name); |
2292 |
net_debugaddr(&rnp->ipv4_addr, ADDR_IPV4); |
2293 |
debug(" port %i\n", rnp->portnr); |
2294 |
rnp = rnp->next; |
2295 |
} |
2296 |
debug_indentation(-iadd); |
2297 |
|
2298 |
debug_indentation(-iadd); |
2299 |
} |
2300 |
|
2301 |
|
2302 |
/* |
2303 |
* net_init(): |
2304 |
* |
2305 |
* This function creates a network, and returns a pointer to it. |
2306 |
* ipv4addr should be something like "10.0.0.0", netipv4len = 8. |
2307 |
* If n_remote is more than zero, remote should be a pointer to an array |
2308 |
* of strings of the following format: "host:portnr". |
2309 |
* |
2310 |
* On failure, exit() is called. |
2311 |
*/ |
2312 |
struct net *net_init(struct emul *emul, int init_flags, |
2313 |
char *ipv4addr, int netipv4len, char **remote, int n_remote, |
2314 |
int local_port) |
2315 |
{ |
2316 |
struct net *net; |
2317 |
int res; |
2318 |
|
2319 |
net = malloc(sizeof(struct net)); |
2320 |
if (net == NULL) { |
2321 |
fprintf(stderr, "net_init(): out of memory\n"); |
2322 |
exit(1); |
2323 |
} |
2324 |
|
2325 |
memset(net, 0, sizeof(struct net)); |
2326 |
|
2327 |
/* Set the back pointer: */ |
2328 |
net->emul = emul; |
2329 |
|
2330 |
/* Sane defaults: */ |
2331 |
net->timestamp = 0; |
2332 |
net->first_ethernet_packet = net->last_ethernet_packet = NULL; |
2333 |
|
2334 |
#ifdef HAVE_INET_PTON |
2335 |
res = inet_pton(AF_INET, ipv4addr, &net->netmask_ipv4); |
2336 |
#else |
2337 |
res = inet_aton(ipv4addr, &net->netmask_ipv4); |
2338 |
#endif |
2339 |
if (res < 1) { |
2340 |
fprintf(stderr, "net_init(): could not parse IPv4 address" |
2341 |
" '%s'\n", ipv4addr); |
2342 |
exit(1); |
2343 |
} |
2344 |
|
2345 |
if (netipv4len < 1 || netipv4len > 30) { |
2346 |
fprintf(stderr, "net_init(): extremely weird ipv4 " |
2347 |
"network length (%i)\n", netipv4len); |
2348 |
exit(1); |
2349 |
} |
2350 |
net->netmask_ipv4_len = netipv4len; |
2351 |
|
2352 |
net->nameserver_known = 0; |
2353 |
net->domain_name = ""; |
2354 |
parse_resolvconf(net); |
2355 |
|
2356 |
/* Distributed network? Then add remote hosts: */ |
2357 |
if (local_port != 0) { |
2358 |
struct sockaddr_in si_self; |
2359 |
|
2360 |
net->local_port = local_port; |
2361 |
net->local_port_socket = socket(AF_INET, SOCK_DGRAM, 0); |
2362 |
if (net->local_port_socket < 0) { |
2363 |
perror("socket"); |
2364 |
exit(1); |
2365 |
} |
2366 |
|
2367 |
memset((char *)&si_self, sizeof(si_self), 0); |
2368 |
si_self.sin_family = AF_INET; |
2369 |
si_self.sin_port = htons(local_port); |
2370 |
si_self.sin_addr.s_addr = htonl(INADDR_ANY); |
2371 |
if (bind(net->local_port_socket, (struct sockaddr *)&si_self, |
2372 |
sizeof(si_self)) < 0) { |
2373 |
perror("bind"); |
2374 |
exit(1); |
2375 |
} |
2376 |
|
2377 |
/* Set the socket to non-blocking: */ |
2378 |
res = fcntl(net->local_port_socket, F_GETFL); |
2379 |
fcntl(net->local_port_socket, F_SETFL, res | O_NONBLOCK); |
2380 |
} |
2381 |
if (n_remote != 0) { |
2382 |
struct remote_net *rnp; |
2383 |
while ((n_remote--) != 0) { |
2384 |
struct hostent *hp; |
2385 |
|
2386 |
/* debug("adding '%s'\n", remote[n_remote]); */ |
2387 |
rnp = malloc(sizeof(struct remote_net)); |
2388 |
memset(rnp, 0, sizeof(struct remote_net)); |
2389 |
|
2390 |
rnp->next = net->remote_nets; |
2391 |
net->remote_nets = rnp; |
2392 |
|
2393 |
rnp->name = strdup(remote[n_remote]); |
2394 |
if (strchr(rnp->name, ':') != NULL) |
2395 |
strchr(rnp->name, ':')[0] = '\0'; |
2396 |
|
2397 |
hp = gethostbyname(rnp->name); |
2398 |
if (hp == NULL) { |
2399 |
fprintf(stderr, "could not resolve '%s'\n", |
2400 |
rnp->name); |
2401 |
exit(1); |
2402 |
} |
2403 |
memcpy(&rnp->ipv4_addr, hp->h_addr, hp->h_length); |
2404 |
free(rnp->name); |
2405 |
|
2406 |
/* And again: */ |
2407 |
rnp->name = strdup(remote[n_remote]); |
2408 |
if (strchr(rnp->name, ':') == NULL) { |
2409 |
fprintf(stderr, "Remote network '%s' is not " |
2410 |
"'host:portnr'?\n", rnp->name); |
2411 |
exit(1); |
2412 |
} |
2413 |
rnp->portnr = atoi(strchr(rnp->name, ':') + 1); |
2414 |
} |
2415 |
} |
2416 |
|
2417 |
if (init_flags & NET_INIT_FLAG_GATEWAY) |
2418 |
net_gateway_init(net); |
2419 |
|
2420 |
net_dumpinfo(net); |
2421 |
|
2422 |
/* This is necessary when using the real network: */ |
2423 |
signal(SIGPIPE, SIG_IGN); |
2424 |
|
2425 |
return net; |
2426 |
} |
2427 |
|