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 1.1.2.32 2002/03/12 14:25:04 guus Exp $
*/
#include "config.h"
#else
#include <net/ethernet.h>
#endif
+#ifdef NEIGHBORSOL
#include <netinet/ip6.h>
#include <netinet/icmp6.h>
+#endif
#include <netinet/if_ether.h>
#include <utils.h>
#include <xalloc.h>
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;
return subnet->owner;
}
-node_t *route_neighborsol(vpn_packet_t *packet)
+#ifdef NEIGHBORSOL
+unsigned short int ipv6_cksum(short int *data, int len, unsigned short int cksum)
+{
+ while(len--)
+ {
+ cksum += ntohs(*data++);
+ }
+ return cksum;
+}
+
+void route_neighborsol(vpn_packet_t *packet)
{
struct ip6_hdr *hdr;
struct nd_neighbor_solicit *ns;
+ struct nd_opt_hdr *opt;
subnet_t *subnet;
+ short int cksum;
+
+ 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));
+ opt = (struct nd_opt_hdr *)(packet->data + 14 + sizeof(struct ip6_hdr) + sizeof(struct nd_neighbor_solicit));
/* 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)
{
}
/* Check if the IPv6 address exists on the VPN */
-
+#if 0
subnet = lookup_subnet_ipv6((ipv6_t *)&ns->nd_ns_target);
if(!subnet)
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]));
}
- return NULL;
+ return;
}
/* Check if it is for our own subnet */
if(subnet->owner == myself)
- return NULL; /* silently ignore */
+ return; /* silently ignore */
+#endif
+
+ syslog(LOG_DEBUG, "Neighbor solicitation request with checksum %hx", ntohs(ns->nd_ns_hdr.icmp6_cksum));
+
+ /* Create pseudo header */
+
+ memcpy(&pseudo.ip6_src, &hdr->ip6_src, 16);
+ memcpy(&pseudo.ip6_dst, &hdr->ip6_dst, 16);
+ pseudo.length = htonl(sizeof(*ns));
+ pseudo.junk[0] = pseudo.junk[1] = pseudo.junk[2] = 0;
+ pseudo.junk[3] = IPPROTO_ICMPV6;
+
+ /* Generate checksum */
+
+ ns->nd_ns_hdr.icmp6_cksum = 0;
+
+ cksum = ipv6_cksum((short int *)&pseudo, sizeof(pseudo)/2, 0);
+
+ syslog(LOG_DEBUG, "Our checksum %hx", cksum);
- /* Forward to destination */
+ cksum = ipv6_cksum((short int *)ns, sizeof(*ns)/2, cksum);
- return subnet->owner;
+ syslog(LOG_DEBUG, "Our checksum %hx", cksum);
+
+ cksum = ipv6_cksum((short int *)opt, sizeof(*opt)/2, cksum);
+
+ syslog(LOG_DEBUG, "Our checksum %hx", cksum);
+
+ /* 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 */
+
+ memcpy(&hdr->ip6_dst, &hdr->ip6_src, 16); /* swap destination and source protocol address */
+ memcpy(&hdr->ip6_src, &ns->nd_ns_target, 16); /* ... */
+
+ 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;
+ 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(struct icmp6_hdr));
+ pseudo.junk[0] = pseudo.junk[1] = pseudo.junk[2] = 0;
+ pseudo.junk[3] = IPPROTO_ICMPV6;
+
+ /* Generate checksum */
+
+ cksum = ipv6_cksum((short int *)&pseudo, sizeof(pseudo)/2, 0);
+ cksum = ipv6_cksum((short int *)ns, sizeof(*ns)/2, cksum);
+
+ ns->nd_ns_hdr.icmp6_cksum = htons(cksum);
+
+ write_packet(packet);
cp
}
+#endif
void route_arp(vpn_packet_t *packet)
{
break;
case 0x86DD:
n = route_ipv6(packet);
+#ifdef NEIGHBORSOL
if(!n && packet->data[0] == 0x33 && packet->data[1] == 0x33 && packet->data[2] == 0xff)
- n = route_neighborsol(packet);
+ {
+ route_neighborsol(packet);
+ return;
+ }
+#endif
break;
case 0x0806:
route_arp(packet);