/*
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 1.1.2.26 2002/03/01 14:09:31 guus Exp $
+ $Id: route.c,v 1.1.2.56 2003/07/07 11:11:33 guus Exp $
*/
#include "config.h"
-#if defined(HAVE_FREEBSD) || defined(HAVE_OPENBSD)
- #include <sys/param.h>
+#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)
- #include <net/if.h>
- #define ETHER_ADDR_LEN 6
-#else
- #include <net/ethernet.h>
+#ifdef HAVE_NET_IF_H
+#include <net/if.h>
+#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/ip.h>
+#include <netinet/ip_icmp.h>
+#ifdef HAVE_NETINET_IP6_H
+#include <netinet/ip6.h>
+#include <netinet/icmp6.h>
#endif
#include <netinet/if_ether.h>
#include <utils.h>
#include <xalloc.h>
-#include <syslog.h>
#include <string.h>
+#ifdef HAVE_INTTYPES_H
+#include <inttypes.h>
+#endif
#include <avl_tree.h>
#include "route.h"
#include "protocol.h"
#include "device.h"
+#include "logger.h"
#include "system.h"
+/* Missing definitions */
+
+#ifndef ETHER_ADDR_LEN
+#define ETHER_ADDR_LEN 6
+#endif
+
+#ifndef ICMP_DEST_UNREACH
+#define ICMP_DEST_UNREACH 3
+#endif
+
+#ifndef ICMP_NET_UNKNOWN
+#define ICMP_NET_UNKNOWN 6
+#endif
+
+#ifndef ICMP_NET_UNREACH
+#define ICMP_NET_UNREACH 0
+#endif
+
int routing_mode = RMODE_ROUTER;
int priorityinheritance = 0;
int macexpire = 600;
-subnet_t mymac;
+int overwrite_mac = 0;
+static mac_t mymac = {{0xFE, 0xFD, 0, 0, 0, 0}};
+
+/* RFC 1071 */
+
+static uint16_t inet_checksum(void *data, int len, uint16_t prevsum)
+{
+ uint16_t *p = data;
+ uint32_t checksum = prevsum ^ 0xFFFF;
+
+ while(len >= 2) {
+ checksum += *p++;
+ len -= 2;
+ }
+
+ if(len)
+ checksum += *(unsigned char *)p;
+
+ while(checksum >> 16)
+ checksum = (checksum & 0xFFFF) + (checksum >> 16);
-void learn_mac(mac_t *address)
+ return ~checksum;
+}
+
+static int ratelimit(void) {
+ static time_t lasttime = 0;
+
+ if(lasttime == now)
+ return 1;
+
+ lasttime = now;
+ return 0;
+}
+
+static void learn_mac(mac_t *address)
{
- subnet_t *subnet;
- avl_node_t *node;
- connection_t *c;
-cp
- subnet = lookup_subnet_mac(address);
-
- /* If we don't know this MAC address yet, store it */
-
- if(!subnet || subnet->owner!=myself)
- {
- if(debug_lvl >= DEBUG_TRAFFIC)
- syslog(LOG_INFO, _("Learned new MAC address %hx:%hx:%hx:%hx:%hx:%hx"),
- address->x[0], address->x[1], address->x[2], address->x[3], address->x[4], address->x[5]);
-
- subnet = new_subnet();
- subnet->type = SUBNET_MAC;
- memcpy(&subnet->net.mac.address, address, sizeof(mac_t));
- subnet_add(myself, subnet);
-
- /* And tell all other tinc daemons it's our MAC */
-
- for(node = connection_tree->head; node; node = node->next)
- {
- c = (connection_t *)node->data;
- if(c->status.active)
- send_add_subnet(c, subnet);
- }
- }
-
- subnet->net.mac.lastseen = now;
+ subnet_t *subnet;
+ avl_node_t *node;
+ connection_t *c;
+
+ cp();
+
+ subnet = lookup_subnet_mac(address);
+
+ /* If we don't know this MAC address yet, store it */
+
+ if(!subnet || subnet->owner != myself) {
+ logger(DEBUG_TRAFFIC, LOG_INFO, _("Learned new MAC address %hx:%hx:%hx:%hx:%hx:%hx"),
+ address->x[0], address->x[1], address->x[2], address->x[3],
+ address->x[4], address->x[5]);
+
+ subnet = new_subnet();
+ subnet->type = SUBNET_MAC;
+ memcpy(&subnet->net.mac.address, address, sizeof(mac_t));
+ subnet_add(myself, subnet);
+
+ /* And tell all other tinc daemons it's our MAC */
+
+ for(node = connection_tree->head; node; node = node->next) {
+ c = (connection_t *) node->data;
+ if(c->status.active)
+ send_add_subnet(c, subnet);
+ }
+ }
+
+ subnet->net.mac.lastseen = now;
}
void age_mac(void)
{
- subnet_t *s;
- connection_t *c;
- avl_node_t *node, *next, *node2;
-cp
- for(node = myself->subnet_tree->head; node; node = next)
- {
- s = (subnet_t *)node->data;
- if(s->type == SUBNET_MAC && s->net.mac.lastseen && s->net.mac.lastseen + macexpire < now)
- {
- for(node2 = connection_tree->head; node2; node2 = node2->next)
- {
- c = (connection_t *)node2->data;
- if(c->status.active)
- send_del_subnet(c, s);
- }
- subnet_del(myself, s);
+ subnet_t *s;
+ connection_t *c;
+ avl_node_t *node, *next, *node2;
+
+ cp();
+
+ for(node = myself->subnet_tree->head; node; node = next) {
+ next = node->next;
+ s = (subnet_t *) node->data;
+ if(s->type == SUBNET_MAC && s->net.mac.lastseen && s->net.mac.lastseen + macexpire < now) {
+ logger(DEBUG_TRAFFIC, LOG_INFO, _("MAC address %hx:%hx:%hx:%hx:%hx:%hx expired"),
+ s->net.mac.address.x[0], s->net.mac.address.x[1],
+ s->net.mac.address.x[2], s->net.mac.address.x[3],
+ s->net.mac.address.x[4], s->net.mac.address.x[5]);
+
+ for(node2 = connection_tree->head; node2; node2 = node2->next) {
+ c = (connection_t *) node2->data;
+ if(c->status.active)
+ send_del_subnet(c, s);
+ }
+
+ subnet_del(myself, s);
+ }
}
- }
-cp
}
-node_t *route_mac(vpn_packet_t *packet)
+static node_t *route_mac(vpn_packet_t *packet)
{
- subnet_t *subnet;
-cp
- /* Learn source address */
-
- learn_mac((mac_t *)(&packet->data[6]));
-
- /* Lookup destination address */
-
- subnet = lookup_subnet_mac((mac_t *)(&packet->data[0]));
-
- if(subnet)
- return subnet->owner;
- else
- return NULL;
+ subnet_t *subnet;
+
+ cp();
+
+ /* Learn source address */
+
+ learn_mac((mac_t *)(&packet->data[6]));
+
+ /* Lookup destination address */
+
+ subnet = lookup_subnet_mac((mac_t *)(&packet->data[0]));
+
+ if(subnet)
+ return subnet->owner;
+ else
+ return NULL;
}
-node_t *route_ipv4(vpn_packet_t *packet)
+/* RFC 792 */
+
+static void route_ipv4_unreachable(vpn_packet_t *packet, uint8_t code)
{
- subnet_t *subnet;
-cp
- if(priorityinheritance)
- packet->priority = packet->data[15];
-
- subnet = lookup_subnet_ipv4((ipv4_t *)&packet->data[30]);
-cp
- if(!subnet)
- {
- if(debug_lvl >= DEBUG_TRAFFIC)
- {
- syslog(LOG_WARNING, _("Cannot route packet: unknown IPv4 destination address %d.%d.%d.%d"),
- packet->data[30], packet->data[31], packet->data[32], packet->data[33]);
- }
-
- return NULL;
- }
-cp
- return subnet->owner;
+ struct ip *hdr;
+ struct icmp *icmp;
+
+ struct in_addr ip_src;
+ struct in_addr ip_dst;
+ uint32_t oldlen;
+
+ if(ratelimit())
+ return;
+
+ cp();
+
+ hdr = (struct ip *)(packet->data + 14);
+ icmp = (struct icmp *)(packet->data + 14 + 20);
+
+ /* Remember original source and destination */
+
+ memcpy(&ip_src, &hdr->ip_src, 4);
+ memcpy(&ip_dst, &hdr->ip_dst, 4);
+ oldlen = packet->len - 14;
+
+ if(oldlen >= IP_MSS - sizeof(*hdr) - sizeof(*icmp))
+ oldlen = IP_MSS - sizeof(*hdr) - sizeof(*icmp);
+
+ /* Copy first part of original contents to ICMP message */
+
+ memmove(&icmp->icmp_ip, hdr, oldlen);
+
+ /* Fill in IPv4 header */
+
+ hdr->ip_v = 4;
+ hdr->ip_hl = sizeof(*hdr) / 4;
+ hdr->ip_tos = 0;
+ hdr->ip_len = htons(20 + 8 + oldlen);
+ hdr->ip_id = 0;
+ hdr->ip_off = 0;
+ hdr->ip_ttl = 255;
+ hdr->ip_p = IPPROTO_ICMP;
+ hdr->ip_sum = 0;
+ memcpy(&hdr->ip_src, &ip_dst, 4);
+ memcpy(&hdr->ip_dst, &ip_src, 4);
+
+ hdr->ip_sum = inet_checksum(hdr, 20, ~0);
+
+ /* Fill in ICMP header */
+
+ icmp->icmp_type = ICMP_DEST_UNREACH;
+ icmp->icmp_code = code;
+ icmp->icmp_cksum = 0;
+
+ icmp->icmp_cksum = inet_checksum(icmp, 8 + oldlen, ~0);
+
+ packet->len = 14 + 20 + 8 + oldlen;
+
+ write_packet(packet);
+}
+
+static node_t *route_ipv4(vpn_packet_t *packet)
+{
+ subnet_t *subnet;
+
+ cp();
+
+ if(priorityinheritance)
+ packet->priority = packet->data[15];
+
+ subnet = lookup_subnet_ipv4((ipv4_t *) & packet->data[30]);
+
+ if(!subnet) {
+ logger(DEBUG_TRAFFIC, LOG_WARNING, _("Cannot route packet: unknown IPv4 destination address %d.%d.%d.%d"),
+ packet->data[30], packet->data[31], packet->data[32],
+ packet->data[33]);
+
+ route_ipv4_unreachable(packet, ICMP_NET_UNKNOWN);
+ return NULL;
+ }
+
+ if(!subnet->owner->status.reachable)
+ route_ipv4_unreachable(packet, ICMP_NET_UNREACH);
+
+ return subnet->owner;
}
-node_t *route_ipv6(vpn_packet_t *packet)
+/* RFC 2463 */
+
+static void route_ipv6_unreachable(vpn_packet_t *packet, uint8_t code)
{
- subnet_t *subnet;
-cp
- subnet = lookup_subnet_ipv6((ipv6_t *)&packet->data[38]);
-cp
- if(!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]));
- }
-
- return NULL;
- }
-cp
- return subnet->owner;
+ struct ip6_hdr *hdr;
+ struct icmp6_hdr *icmp;
+ uint16_t checksum;
+
+ struct {
+ struct in6_addr ip6_src; /* source address */
+ struct in6_addr ip6_dst; /* destination address */
+ uint32_t length;
+ uint32_t next;
+ } pseudo;
+
+ if(ratelimit())
+ return;
+
+ cp();
+
+ hdr = (struct ip6_hdr *)(packet->data + 14);
+ icmp = (struct icmp6_hdr *)(packet->data + 14 + sizeof(*hdr));
+
+ /* Remember original source and destination */
+
+ memcpy(&pseudo.ip6_src, &hdr->ip6_dst, 16);
+ memcpy(&pseudo.ip6_dst, &hdr->ip6_src, 16);
+ pseudo.length = ntohs(hdr->ip6_plen) + sizeof(*hdr);
+
+ if(pseudo.length >= IP_MSS - sizeof(*hdr) - sizeof(*icmp))
+ pseudo.length = IP_MSS - sizeof(*hdr) - sizeof(*icmp);
+
+ /* Copy first part of original contents to ICMP message */
+
+ memmove(((char *)icmp) + sizeof(*icmp), hdr, pseudo.length);
+
+ /* Fill in IPv6 header */
+
+ hdr->ip6_flow = htonl(0x60000000UL);
+ hdr->ip6_plen = htons(sizeof(*icmp) + pseudo.length);
+ hdr->ip6_nxt = IPPROTO_ICMPV6;
+ hdr->ip6_hlim = 255;
+ memcpy(&hdr->ip6_dst, &pseudo.ip6_dst, 16);
+ memcpy(&hdr->ip6_src, &pseudo.ip6_src, 16);
+
+ /* Fill in ICMP header */
+
+ icmp->icmp6_type = ICMP6_DST_UNREACH;
+ icmp->icmp6_code = code;
+ icmp->icmp6_cksum = 0;
+
+ /* Create pseudo header */
+
+ pseudo.length = htonl(sizeof(*icmp) + pseudo.length);
+ pseudo.next = htonl(IPPROTO_ICMPV6);
+
+ /* Generate checksum */
+
+ checksum = inet_checksum(&pseudo, sizeof(pseudo), ~0);
+ checksum = inet_checksum(icmp, ntohl(pseudo.length), checksum);
+
+ icmp->icmp6_cksum = checksum;
+
+ packet->len = 14 + sizeof(*hdr) + ntohl(pseudo.length);
+
+ write_packet(packet);
}
-void route_arp(vpn_packet_t *packet)
+static node_t *route_ipv6(vpn_packet_t *packet)
{
- struct ether_arp *arp;
- subnet_t *subnet;
- unsigned char ipbuf[4];
-cp
- /* First, snatch the source address from the ARP packet */
-
- memcpy(mymac.net.mac.address.x, packet->data + 6, 6);
-
- /* This routine generates replies to ARP requests.
- You don't need to set NOARP flag on the interface anymore (which is broken on FreeBSD).
- Most of the code here is taken from choparp.c by Takamichi Tateoka (tree@mma.club.uec.ac.jp)
- */
-
- arp = (struct ether_arp *)(packet->data + 14);
-
- /* Check if this is a valid ARP request */
-
- 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 ||
- ntohs(arp->arp_op) != ARPOP_REQUEST )
- {
- if(debug_lvl > DEBUG_TRAFFIC)
- {
- syslog(LOG_WARNING, _("Cannot route packet: received unknown type ARP request"));
- }
- return;
- }
-
- /* Check if the IP address exists on the VPN */
-
- subnet = lookup_subnet_ipv4((ipv4_t *)arp->arp_tpa);
-
- if(!subnet)
- {
- if(debug_lvl >= DEBUG_TRAFFIC)
- {
- syslog(LOG_WARNING, _("Cannot route packet: ARP request for unknown address %d.%d.%d.%d"),
- arp->arp_tpa[0], arp->arp_tpa[1], arp->arp_tpa[2], arp->arp_tpa[3]);
- }
-
- return;
- }
-
- /* Check if it is for our own subnet */
-
- if(subnet->owner == myself)
- return; /* silently ignore */
-
- 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(ipbuf, arp->arp_tpa, 4); /* save protocol addr */
- memcpy(arp->arp_tpa, arp->arp_spa, 4); /* swap destination and source protocol address */
- memcpy(arp->arp_spa, ipbuf, 4); /* ... */
-
- memcpy(arp->arp_tha, arp->arp_sha, 10); /* set target hard/proto addr */
- memcpy(arp->arp_sha, packet->data + ETHER_ADDR_LEN, ETHER_ADDR_LEN); /* add fake source hard addr */
- arp->arp_op = htons(ARPOP_REPLY);
-
- write_packet(packet);
-cp
+ subnet_t *subnet;
+
+ cp();
+
+ subnet = lookup_subnet_ipv6((ipv6_t *) & packet->data[38]);
+
+ if(!subnet) {
+ logger(DEBUG_TRAFFIC, LOG_WARNING, _("Cannot route packet: unknown IPv6 destination address %hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx"),
+ 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]));
+ route_ipv6_unreachable(packet, ICMP6_DST_UNREACH_ADDR);
+
+ return NULL;
+ }
+
+ if(!subnet->owner->status.reachable)
+ route_ipv6_unreachable(packet, ICMP6_DST_UNREACH_NOROUTE);
+
+ return subnet->owner;
+}
+
+/* RFC 2461 */
+
+static 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;
+ uint32_t next;
+ } pseudo;
+
+ cp();
+
+ hdr = (struct ip6_hdr *)(packet->data + 14);
+ 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 */
+
+ if(overwrite_mac)
+ memcpy(mymac.x, packet->data + 6, 6);
+
+ /* Check if this is a valid neighbor solicitation request */
+
+ if(ns->nd_ns_hdr.icmp6_type != ND_NEIGHBOR_SOLICIT ||
+ opt->nd_opt_type != ND_OPT_SOURCE_LINKADDR) {
+ logger(DEBUG_TRAFFIC, LOG_WARNING, _("Cannot route packet: received unknown type neighbor solicitation request"));
+ 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.next = htonl(IPPROTO_ICMPV6);
+
+ /* Generate checksum */
+
+ checksum = inet_checksum(&pseudo, sizeof(pseudo), ~0);
+ checksum = inet_checksum(ns, sizeof(*ns) + 8, checksum);
+
+ if(checksum) {
+ logger(DEBUG_TRAFFIC, 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(!subnet) {
+ logger(DEBUG_TRAFFIC, LOG_WARNING, _("Cannot route packet: neighbor solicitation request for unknown address %hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx"),
+ 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;
+ }
+
+ /* Check if it is for our own subnet */
+
+ if(subnet->owner == myself)
+ 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 */
+
+ 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;
+ 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.next = htonl(IPPROTO_ICMPV6);
+
+ /* Generate checksum */
+
+ checksum = inet_checksum(&pseudo, sizeof(pseudo), ~0);
+ checksum = inet_checksum(ns, sizeof(*ns) + 8, checksum);
+
+ ns->nd_ns_hdr.icmp6_cksum = checksum;
+
+ write_packet(packet);
+}
+
+/* RFC 826 */
+
+static void route_arp(vpn_packet_t *packet)
+{
+ struct ether_arp *arp;
+ subnet_t *subnet;
+ uint8_t ipbuf[4];
+
+ cp();
+
+ /* First, snatch the source address from the ARP packet */
+
+ if(overwrite_mac)
+ memcpy(mymac.x, packet->data + 6, 6);
+
+ /* This routine generates replies to ARP requests.
+ You don't need to set NOARP flag on the interface anymore (which is broken on FreeBSD).
+ Most of the code here is taken from choparp.c by Takamichi Tateoka (tree@mma.club.uec.ac.jp)
+ */
+
+ arp = (struct ether_arp *)(packet->data + 14);
+
+ /* Check if this is a valid ARP request */
+
+ if(ntohs(arp->arp_hrd) != ARPHRD_ETHER || ntohs(arp->arp_pro) != ETHERTYPE_IP ||
+ arp->arp_hln != ETHER_ADDR_LEN || arp->arp_pln != 4 || ntohs(arp->arp_op) != ARPOP_REQUEST) {
+ logger(DEBUG_TRAFFIC, LOG_WARNING, _("Cannot route packet: received unknown type ARP request"));
+ return;
+ }
+
+ /* Check if the IPv4 address exists on the VPN */
+
+ subnet = lookup_subnet_ipv4((ipv4_t *) arp->arp_tpa);
+
+ if(!subnet) {
+ logger(DEBUG_TRAFFIC, LOG_WARNING, _("Cannot route packet: ARP request for unknown address %d.%d.%d.%d"),
+ arp->arp_tpa[0], arp->arp_tpa[1], arp->arp_tpa[2],
+ arp->arp_tpa[3]);
+ return;
+ }
+
+ /* Check if it is for our own subnet */
+
+ if(subnet->owner == myself)
+ return; /* silently ignore */
+
+ 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(ipbuf, arp->arp_tpa, 4); /* save protocol addr */
+ memcpy(arp->arp_tpa, arp->arp_spa, 4); /* swap destination and source protocol address */
+ memcpy(arp->arp_spa, ipbuf, 4); /* ... */
+
+ memcpy(arp->arp_tha, arp->arp_sha, 10); /* set target hard/proto addr */
+ memcpy(arp->arp_sha, packet->data + ETHER_ADDR_LEN, ETHER_ADDR_LEN); /* add fake source hard addr */
+ arp->arp_op = htons(ARPOP_REPLY);
+
+ write_packet(packet);
}
void route_outgoing(vpn_packet_t *packet)
{
- unsigned short int type;
- node_t *n;
-cp
- /* FIXME: multicast? */
-
- switch(routing_mode)
- {
- case RMODE_ROUTER:
- type = ntohs(*((unsigned short*)(&packet->data[12])));
- switch(type)
- {
- case 0x0800:
- n = route_ipv4(packet);
- break;
- case 0x86DD:
- n = route_ipv6(packet);
- break;
- case 0x0806:
- route_arp(packet);
- return;
- default:
- if(debug_lvl >= DEBUG_TRAFFIC)
- {
- syslog(LOG_WARNING, _("Cannot route packet: unknown type %hx"), type);
- }
- return;
- }
- if(n)
- send_packet(n, packet);
- break;
-
- case RMODE_SWITCH:
- n = route_mac(packet);
- if(n)
- send_packet(n, packet);
- else
- broadcast_packet(myself, packet);
- break;
-
- case RMODE_HUB:
- broadcast_packet(myself, packet);
- break;
- }
+ uint16_t type;
+ node_t *n = NULL;
+
+ cp();
+
+ /* FIXME: multicast? */
+
+ switch (routing_mode) {
+ case RMODE_ROUTER:
+ 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);
+ break;
+
+ case 0x0806:
+ route_arp(packet);
+ return;
+
+ default:
+ logger(DEBUG_TRAFFIC, LOG_WARNING, _("Cannot route packet: unknown type %hx"), type);
+ return;
+ }
+ if(n)
+ send_packet(n, packet);
+ break;
+
+ case RMODE_SWITCH:
+ n = route_mac(packet);
+ if(n)
+ send_packet(n, packet);
+ else
+ broadcast_packet(myself, packet);
+ break;
+
+ case RMODE_HUB:
+ broadcast_packet(myself, packet);
+ break;
+ }
}
void route_incoming(node_t *source, vpn_packet_t *packet)
{
- switch(routing_mode)
- {
- case RMODE_ROUTER:
- {
- node_t *n;
-
- n = route_ipv4(packet);
-
- if(n)
- {
- if(n == myself)
- {
- memcpy(packet->data, mymac.net.mac.address.x, 6);
- write_packet(packet);
- }
- else
- send_packet(n, packet);
- }
- }
- break;
- case RMODE_SWITCH:
- {
- subnet_t *subnet;
-
- subnet = lookup_subnet_mac((mac_t *)(&packet->data[0]));
-
- if(subnet)
- {
- if(subnet->owner == myself)
- write_packet(packet);
- else
- send_packet(subnet->owner, packet);
- }
- else
- {
- broadcast_packet(source, packet);
- write_packet(packet);
- }
- }
- break;
- case RMODE_HUB:
- broadcast_packet(source, packet); /* Spread it on */
- write_packet(packet);
- break;
- }
+ switch (routing_mode) {
+ case RMODE_ROUTER:
+ {
+ node_t *n = NULL;
+ uint16_t type;
+
+ type = ntohs(*((uint16_t *)(&packet->data[12])));
+ switch (type) {
+ case 0x0800:
+ n = route_ipv4(packet);
+ break;
+
+ case 0x86DD:
+ n = route_ipv6(packet);
+ break;
+
+ default:
+ n = myself;
+ break;
+ }
+
+ if(n) {
+ if(n == myself) {
+ if(overwrite_mac)
+ memcpy(packet->data, mymac.x, 6);
+ write_packet(packet);
+ } else
+ send_packet(n, packet);
+ }
+ }
+ break;
+
+ case RMODE_SWITCH:
+ {
+ subnet_t *subnet;
+
+ subnet = lookup_subnet_mac((mac_t *)(&packet->data[0]));
+
+ if(subnet) {
+ if(subnet->owner == myself)
+ write_packet(packet);
+ else
+ send_packet(subnet->owner, packet);
+ } else {
+ broadcast_packet(source, packet);
+ write_packet(packet);
+ }
+ }
+ break;
+
+ case RMODE_HUB:
+ broadcast_packet(source, packet); /* Spread it on */
+ write_packet(packet);
+ break;
+ }
}
projects / tinc / blobdiff