/*
route.c -- routing
- Copyright (C) 2000-2002 Ivo Timmermans <itimmermans@bigfoot.com>,
- 2000-2002 Guus Sliepen <guus@sliepen.warande.net>
+ Copyright (C) 2000-2002 Ivo Timmermans <ivo@o2w.nl>,
+ 2000-2002 Guus Sliepen <guus@sliepen.eu.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- $Id: route.c,v 1.1.2.31 2002/03/11 13:56:00 guus Exp $
+ $Id: route.c,v 1.1.2.43 2002/06/21 10:11:33 guus Exp $
*/
#include "config.h"
-#if defined(HAVE_FREEBSD) || defined(HAVE_OPENBSD)
+#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#include <sys/socket.h>
#include <netinet/in.h>
-#if defined(HAVE_SOLARIS) || defined(HAVE_OPENBSD)
+#ifdef HAVE_NET_IF_H
#include <net/if.h>
- #define ETHER_ADDR_LEN 6
-#else
+#endif
+#ifdef HAVE_NET_ETHERNET_H
#include <net/ethernet.h>
#endif
+#ifdef HAVE_NETINET_IN_SYSTM_H
+ #include <netinet/in_systm.h>
+#endif
#include <netinet/ip6.h>
#include <netinet/icmp6.h>
#include <netinet/if_ether.h>
#include <xalloc.h>
#include <syslog.h>
#include <string.h>
+#ifdef HAVE_INTTYPES_H
+ #include <inttypes.h>
+#endif
#include <avl_tree.h>
#include "system.h"
+#ifndef ETHER_ADDR_LEN
+ #define ETHER_ADDR_LEN 6
+#endif
+
int routing_mode = RMODE_ROUTER;
int priorityinheritance = 0;
int macexpire = 600;
subnet_t mymac;
-#ifdef HAVE_FREEBSD
-#define s6_addr16 __u6_addr.__u6_addr16
-#endif
-
void learn_mac(mac_t *address)
{
subnet_t *subnet;
if(debug_lvl >= DEBUG_TRAFFIC)
{
syslog(LOG_WARNING, _("Cannot route packet: unknown IPv6 destination address %hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx"),
- ntohs(*(short unsigned int *)&packet->data[38]),
- ntohs(*(short unsigned int *)&packet->data[40]),
- ntohs(*(short unsigned int *)&packet->data[42]),
- ntohs(*(short unsigned int *)&packet->data[44]),
- ntohs(*(short unsigned int *)&packet->data[46]),
- ntohs(*(short unsigned int *)&packet->data[48]),
- ntohs(*(short unsigned int *)&packet->data[50]),
- ntohs(*(short unsigned int *)&packet->data[52]));
+ ntohs(*(uint16_t *)&packet->data[38]),
+ ntohs(*(uint16_t *)&packet->data[40]),
+ ntohs(*(uint16_t *)&packet->data[42]),
+ ntohs(*(uint16_t *)&packet->data[44]),
+ ntohs(*(uint16_t *)&packet->data[46]),
+ ntohs(*(uint16_t *)&packet->data[48]),
+ ntohs(*(uint16_t *)&packet->data[50]),
+ ntohs(*(uint16_t *)&packet->data[52]));
}
return NULL;
return subnet->owner;
}
-node_t *route_neighborsol(vpn_packet_t *packet)
+uint16_t inet_checksum(uint16_t *data, int len, uint16_t prevsum)
+{
+ uint32_t checksum = prevsum ^ 0xFFFF;
+
+ while(len--)
+ checksum += ntohs(*data++);
+
+ while(checksum >> 16)
+ checksum = (checksum & 0xFFFF) + (checksum >> 16);
+
+ return checksum ^ 0xFFFF;
+}
+
+void route_neighborsol(vpn_packet_t *packet)
{
struct ip6_hdr *hdr;
struct nd_neighbor_solicit *ns;
+ struct nd_opt_hdr *opt;
subnet_t *subnet;
+ uint16_t checksum;
+
+ struct {
+ struct in6_addr ip6_src; /* source address */
+ struct in6_addr ip6_dst; /* destination address */
+ uint32_t length;
+ uint8_t junk[4];
+ } pseudo;
+
cp
hdr = (struct ip6_hdr *)(packet->data + 14);
- ns = (struct nd_neighbor_solicit *)(packet->data + 14 + sizeof(struct ip6_hdr));
+ ns = (struct nd_neighbor_solicit *)(packet->data + 14 + sizeof(*hdr));
+ opt = (struct nd_opt_hdr *)(packet->data + 14 + sizeof(*hdr) + sizeof(*ns));
/* First, snatch the source address from the neighbor solicitation packet */
/* Check if this is a valid neighbor solicitation request */
- if(ns->nd_ns_hdr.icmp6_type != ND_NEIGHBOR_SOLICIT)
+ if(ns->nd_ns_hdr.icmp6_type != ND_NEIGHBOR_SOLICIT ||
+ opt->nd_opt_type != ND_OPT_SOURCE_LINKADDR)
{
if(debug_lvl > DEBUG_TRAFFIC)
{
return;
}
+ /* Create pseudo header */
+
+ memcpy(&pseudo.ip6_src, &hdr->ip6_src, 16);
+ memcpy(&pseudo.ip6_dst, &hdr->ip6_dst, 16);
+ pseudo.length = htonl(sizeof(*ns) + sizeof(*opt) + 6);
+ pseudo.junk[0] = pseudo.junk[1] = pseudo.junk[2] = 0;
+ pseudo.junk[3] = IPPROTO_ICMPV6;
+
+ /* Generate checksum */
+
+ checksum = inet_checksum((uint16_t *)&pseudo, sizeof(pseudo)/2, ~0);
+ checksum = inet_checksum((uint16_t *)ns, sizeof(*ns)/2 + 4, checksum);
+
+ if(checksum)
+ {
+ if(debug_lvl >= DEBUG_TRAFFIC)
+ syslog(LOG_WARNING, _("Cannot route packet: checksum error for neighbor solicitation request"));
+ return;
+ }
+
/* Check if the IPv6 address exists on the VPN */
subnet = lookup_subnet_ipv6((ipv6_t *)&ns->nd_ns_target);
if(debug_lvl >= DEBUG_TRAFFIC)
{
syslog(LOG_WARNING, _("Cannot route packet: neighbor solicitation request for unknown address %hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx"),
- ntohs(ns->nd_ns_target.s6_addr16[0]), ntohs(ns->nd_ns_target.s6_addr16[1]), ntohs(ns->nd_ns_target.s6_addr16[2]), ntohs(ns->nd_ns_target.s6_addr16[3]),
- ntohs(ns->nd_ns_target.s6_addr16[4]), ntohs(ns->nd_ns_target.s6_addr16[5]), ntohs(ns->nd_ns_target.s6_addr16[6]), ntohs(ns->nd_ns_target.s6_addr16[7]));
+ ntohs(((uint16_t *)&ns->nd_ns_target)[0]), ntohs(((uint16_t *)&ns->nd_ns_target)[1]), ntohs(((uint16_t *)&ns->nd_ns_target)[2]), ntohs(((uint16_t *)&ns->nd_ns_target)[3]),
+ ntohs(((uint16_t *)&ns->nd_ns_target)[4]), ntohs(((uint16_t *)&ns->nd_ns_target)[5]), ntohs(((uint16_t *)&ns->nd_ns_target)[6]), ntohs(((uint16_t *)&ns->nd_ns_target)[7]));
}
- return NULL;
+ return;
}
/* Check if it is for our own subnet */
if(subnet->owner == myself)
- return NULL; /* silently ignore */
+ return; /* silently ignore */
+
+ /* Create neighbor advertation reply */
+
+ memcpy(packet->data, packet->data + ETHER_ADDR_LEN, ETHER_ADDR_LEN); /* copy destination address */
+ packet->data[ETHER_ADDR_LEN*2 - 1] ^= 0xFF; /* mangle source address so it looks like it's not from us */
- /* Forward to destination */
+ memcpy(&hdr->ip6_dst, &hdr->ip6_src, 16); /* swap destination and source protocol address */
+ memcpy(&hdr->ip6_src, &ns->nd_ns_target, 16); /* ... */
- return subnet->owner;
+ memcpy((char *)opt + sizeof(*opt), packet->data + ETHER_ADDR_LEN, 6); /* add fake source hard addr */
+
+ ns->nd_ns_hdr.icmp6_cksum = 0;
+ ns->nd_ns_hdr.icmp6_type = ND_NEIGHBOR_ADVERT;
+ ns->nd_ns_hdr.icmp6_dataun.icmp6_un_data8[0] = 0x40; /* Set solicited flag */
+ ns->nd_ns_hdr.icmp6_dataun.icmp6_un_data8[1] = ns->nd_ns_hdr.icmp6_dataun.icmp6_un_data8[2] = ns->nd_ns_hdr.icmp6_dataun.icmp6_un_data8[3] = 0;
+ opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
+
+ /* Create pseudo header */
+
+ memcpy(&pseudo.ip6_src, &hdr->ip6_src, 16);
+ memcpy(&pseudo.ip6_dst, &hdr->ip6_dst, 16);
+ pseudo.length = htonl(sizeof(*ns) + sizeof(*opt) + 6);
+ pseudo.junk[0] = pseudo.junk[1] = pseudo.junk[2] = 0;
+ pseudo.junk[3] = IPPROTO_ICMPV6;
+
+ /* Generate checksum */
+
+ checksum = inet_checksum((uint16_t *)&pseudo, sizeof(pseudo)/2, ~0);
+ checksum = inet_checksum((uint16_t *)ns, sizeof(*ns)/2 + 4, checksum);
+
+ ns->nd_ns_hdr.icmp6_cksum = htons(checksum);
+
+ write_packet(packet);
cp
}
{
struct ether_arp *arp;
subnet_t *subnet;
- unsigned char ipbuf[4];
+ uint8_t ipbuf[4];
cp
/* First, snatch the source address from the ARP packet */
if(ntohs(arp->arp_hrd) != ARPHRD_ETHER ||
ntohs(arp->arp_pro) != ETHERTYPE_IP ||
- (int) (arp->arp_hln) != ETHER_ADDR_LEN ||
- (int) (arp->arp_pln) != 4 ||
+ arp->arp_hln != ETHER_ADDR_LEN ||
+ arp->arp_pln != 4 ||
ntohs(arp->arp_op) != ARPOP_REQUEST )
{
if(debug_lvl > DEBUG_TRAFFIC)
void route_outgoing(vpn_packet_t *packet)
{
- unsigned short int type;
+ uint16_t type;
node_t *n = NULL;
cp
/* FIXME: multicast? */
switch(routing_mode)
{
case RMODE_ROUTER:
- type = ntohs(*((unsigned short*)(&packet->data[12])));
+ type = ntohs(*((uint16_t *)(&packet->data[12])));
switch(type)
{
case 0x0800:
n = route_ipv4(packet);
break;
case 0x86DD:
+ if(packet->data[20] == IPPROTO_ICMPV6 && packet->data[54] == ND_NEIGHBOR_SOLICIT)
+ {
+ route_neighborsol(packet);
+ return;
+ }
n = route_ipv6(packet);
- if(!n && packet->data[0] == 0x33 && packet->data[1] == 0x33 && packet->data[2] == 0xff)
- n = route_neighborsol(packet);
break;
case 0x0806:
route_arp(packet);
case RMODE_ROUTER:
{
node_t *n = NULL;
- unsigned short int type;
+ uint16_t type;
- type = ntohs(*((unsigned short*)(&packet->data[12])));
+ type = ntohs(*((uint16_t *)(&packet->data[12])));
switch(type)
{
case 0x0800: