From f219f156cf13fd30369d7cd4632c406ffd6ff628 Mon Sep 17 00:00:00 2001 From: Guus Sliepen Date: Tue, 12 Mar 2002 14:25:04 +0000 Subject: [PATCH 1/1] Put #ifdef NEIGHBORSOL around corresponding code. --- src/route.c | 106 +++++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 93 insertions(+), 13 deletions(-) diff --git a/src/route.c b/src/route.c index bd4341da..0799c48c 100644 --- a/src/route.c +++ b/src/route.c @@ -17,7 +17,7 @@ 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" @@ -33,8 +33,10 @@ #else #include #endif +#ifdef NEIGHBORSOL #include #include +#endif #include #include #include @@ -57,10 +59,6 @@ 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; @@ -190,14 +188,35 @@ cp 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 */ @@ -205,7 +224,8 @@ cp /* 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) { @@ -215,7 +235,7 @@ cp } /* Check if the IPv6 address exists on the VPN */ - +#if 0 subnet = lookup_subnet_ipv6((ipv6_t *)&ns->nd_ns_target); if(!subnet) @@ -227,19 +247,74 @@ cp 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) { @@ -326,8 +401,13 @@ cp 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); -- 2.20.1