/*
route.c -- routing
- Copyright (C) 2000-2002 Ivo Timmermans <ivo@o2w.nl>,
- 2000-2002 Guus Sliepen <guus@sliepen.eu.org>
+ Copyright (C) 2000-2003 Ivo Timmermans <ivo@o2w.nl>,
+ 2000-2003 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 1.1.2.47 2003/03/29 21:51:21 guus Exp $
+ $Id: route.c,v 1.1.2.68 2003/10/06 13:57:12 guus Exp $
*/
-#include "config.h"
+#include "system.h"
-#ifdef HAVE_SYS_PARAM_H
-#include <sys/param.h>
-#endif
-#include <sys/socket.h>
-#include <netinet/in.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>
+#ifdef HAVE_NET_IF_ARP_H
+#include <net/if_arp.h>
#endif
-#include <netinet/ip.h>
+#ifdef HAVE_NETINET_IP_ICMP_H
#include <netinet/ip_icmp.h>
-#include <netinet/ip6.h>
+#endif
+#ifdef HAVE_NETINET_ICMP6_H
#include <netinet/icmp6.h>
+#endif
+#ifdef HAVE_NETINET_IF_ETHER_H
#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 "net.h"
+#include "avl_tree.h"
#include "connection.h"
-#include "subnet.h"
-#include "route.h"
-#include "protocol.h"
#include "device.h"
+#include "ethernet.h"
+#include "ipv4.h"
+#include "ipv6.h"
+#include "logger.h"
+#include "net.h"
+#include "protocol.h"
+#include "route.h"
+#include "subnet.h"
+#include "utils.h"
-#include "system.h"
+rmode_t routing_mode = RMODE_ROUTER;
+bool priorityinheritance = false;
+int macexpire = 600;
+bool overwrite_mac = false;
+mac_t mymac = {{0xFE, 0xFD, 0, 0, 0, 0}};
-#ifndef ETHER_ADDR_LEN
-#define ETHER_ADDR_LEN 6
-#endif
+/* Sizes of various headers */
-int routing_mode = RMODE_ROUTER;
-int priorityinheritance = 0;
-int macexpire = 600;
-subnet_t mymac;
+static const size_t ether_size = sizeof(struct ether_header);
+static const size_t arp_size = sizeof(struct ether_arp);
+static const size_t ip_size = sizeof(struct ip);
+static const size_t icmp_size = sizeof(struct icmp) - sizeof(struct ip);
+static const size_t ip6_size = sizeof(struct ip6_hdr);
+static const size_t icmp6_size = sizeof(struct icmp6_hdr);
+static const size_t ns_size = sizeof(struct nd_neighbor_solicit);
+static const size_t opt_size = sizeof(struct nd_opt_hdr);
/* RFC 1071 */
-uint16_t inet_checksum(void *data, int len, uint16_t prevsum)
+static uint16_t inet_checksum(void *data, int len, uint16_t prevsum)
{
uint16_t *p = data;
uint32_t checksum = prevsum ^ 0xFFFF;
- len /= 2;
-
- while(len--)
+ while(len >= 2) {
checksum += *p++;
+ len -= 2;
+ }
+
+ if(len)
+ checksum += *(unsigned char *)p;
while(checksum >> 16)
checksum = (checksum & 0xFFFF) + (checksum >> 16);
return ~checksum;
}
-int ratelimit(void) {
+static bool ratelimit(int frequency) {
static time_t lasttime = 0;
+ static int count = 0;
- if(lasttime == now)
- return 1;
+ if(lasttime == now) {
+ if(++count > frequency)
+ return true;
+ } else {
+ lasttime = now;
+ count = 0;
+ }
- lasttime = now;
- return 0;
+ return false;
}
-void learn_mac(mac_t *address)
+static void learn_mac(mac_t *address)
{
subnet_t *subnet;
avl_node_t *node;
/* 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"),
+ ifdebug(TRAFFIC) logger(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]);
/* And tell all other tinc daemons it's our MAC */
for(node = connection_tree->head; node; node = node->next) {
- c = (connection_t *) node->data;
+ c = node->data;
if(c->status.active)
send_add_subnet(c, subnet);
}
for(node = myself->subnet_tree->head; node; node = next) {
next = node->next;
- s = (subnet_t *) node->data;
+ s = node->data;
if(s->type == SUBNET_MAC && s->net.mac.lastseen && s->net.mac.lastseen + macexpire < now) {
- if(debug_lvl >= DEBUG_TRAFFIC)
- syslog(LOG_INFO, _("MAC address %hx:%hx:%hx:%hx:%hx:%hx expired"),
+ ifdebug(TRAFFIC) logger(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;
+ c = node2->data;
if(c->status.active)
send_del_subnet(c, s);
}
}
}
-node_t *route_mac(vpn_packet_t *packet)
+static node_t *route_mac(vpn_packet_t *packet)
{
subnet_t *subnet;
/* RFC 792 */
-void route_ipv4_unreachable(vpn_packet_t *packet, uint8_t code)
+static void route_ipv4_unreachable(vpn_packet_t *packet, uint8_t code)
{
- struct ip *hdr;
- struct icmp *icmp;
+ struct ip ip;
+ struct icmp icmp;
struct in_addr ip_src;
struct in_addr ip_dst;
uint32_t oldlen;
- if(ratelimit())
+ if(ratelimit(3))
return;
cp();
- hdr = (struct ip *)(packet->data + 14);
- icmp = (struct icmp *)(packet->data + 14 + 20);
+ /* Copy headers from packet into properly aligned structs on the stack */
+
+ memcpy(&ip, packet->data + ether_size, ip_size);
+ memcpy(&icmp, packet->data + ether_size + ip_size, icmp_size);
/* Remember original source and destination */
- memcpy(&ip_src, &hdr->ip_src, 4);
- memcpy(&ip_dst, &hdr->ip_dst, 4);
- oldlen = packet->len - 14;
+ memcpy(&ip_src, &ip.ip_src, sizeof(ip_src));
+ memcpy(&ip_dst, &ip.ip_dst, sizeof(ip_dst));
+
+ oldlen = packet->len - ether_size;
- if(oldlen >= IP_MSS - sizeof(*hdr) - sizeof(struct icmphdr))
- oldlen = IP_MSS - sizeof(*hdr) - sizeof(struct icmphdr);
+ if(oldlen >= IP_MSS - ip_size - icmp_size)
+ oldlen = IP_MSS - ip_size - icmp_size;
/* Copy first part of original contents to ICMP message */
- memmove(&icmp->icmp_ip, hdr, oldlen);
+ memmove(packet->data + ether_size + ip_size + icmp_size, packet->data + ether_size, 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);
+ ip.ip_v = 4;
+ ip.ip_hl = ip_size / 4;
+ ip.ip_tos = 0;
+ ip.ip_len = htons(ip_size + icmp_size + oldlen);
+ ip.ip_id = 0;
+ ip.ip_off = 0;
+ ip.ip_ttl = 255;
+ ip.ip_p = IPPROTO_ICMP;
+ ip.ip_sum = 0;
+ memcpy(&ip.ip_src, &ip_dst, sizeof(ip_src));
+ memcpy(&ip.ip_dst, &ip_src, sizeof(ip_dst));
+
+ ip.ip_sum = inet_checksum(&ip, ip_size, ~0);
/* Fill in ICMP header */
- icmp->icmp_type = ICMP_DEST_UNREACH;
- icmp->icmp_code = code;
- icmp->icmp_cksum = 0;
+ icmp.icmp_type = ICMP_DEST_UNREACH;
+ icmp.icmp_code = code;
+ icmp.icmp_cksum = 0;
- icmp->icmp_cksum = inet_checksum(icmp, 8 + oldlen, ~0);
+ icmp.icmp_cksum = inet_checksum(&icmp, icmp_size, ~0);
+ icmp.icmp_cksum = inet_checksum(packet->data + ether_size + ip_size + icmp_size, oldlen, icmp.icmp_cksum);
+
+ /* Copy structs on stack back to packet */
+
+ memcpy(packet->data + ether_size, &ip, ip_size);
+ memcpy(packet->data + ether_size + ip_size, &icmp, icmp_size);
- packet->len = 14 + 20 + 8 + oldlen;
+ packet->len = ether_size + ip_size + icmp_size + oldlen;
write_packet(packet);
}
-node_t *route_ipv4(vpn_packet_t *packet)
+static node_t *route_ipv4(vpn_packet_t *packet)
{
subnet_t *subnet;
if(priorityinheritance)
packet->priority = packet->data[15];
- subnet = lookup_subnet_ipv4((ipv4_t *) & packet->data[30]);
+ subnet = lookup_subnet_ipv4((ipv4_t *) &packet->data[30]);
if(!subnet) {
- if(debug_lvl >= DEBUG_TRAFFIC) {
- syslog(LOG_WARNING, _("Cannot route packet: unknown IPv4 destination address %d.%d.%d.%d"),
+ ifdebug(TRAFFIC) logger(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;
/* RFC 2463 */
-void route_ipv6_unreachable(vpn_packet_t *packet, uint8_t code)
+static void route_ipv6_unreachable(vpn_packet_t *packet, uint8_t code)
{
- struct ip6_hdr *hdr;
- struct icmp6_hdr *icmp;
+ struct ip6_hdr ip6;
+ struct icmp6_hdr icmp6;
uint16_t checksum;
struct {
uint32_t next;
} pseudo;
- if(ratelimit())
+ if(ratelimit(3))
return;
cp();
- hdr = (struct ip6_hdr *)(packet->data + 14);
- icmp = (struct icmp6_hdr *)(packet->data + 14 + sizeof(*hdr));
+ /* Copy headers from packet to structs on the stack */
+
+ memcpy(&ip6, packet->data + ether_size, ip6_size);
+ memcpy(&icmp6, packet->data + ether_size + ip6_size, icmp6_size);
/* Remember original source and destination */
- memcpy(&pseudo.ip6_src, &hdr->ip6_src, 16);
- memcpy(&pseudo.ip6_dst, &hdr->ip6_dst, 16);
- pseudo.length = ntohs(hdr->ip6_plen) + sizeof(*hdr);
+ memcpy(&pseudo.ip6_src, &ip6.ip6_dst, sizeof(ip6.ip6_src));
+ memcpy(&pseudo.ip6_dst, &ip6.ip6_src, sizeof(ip6.ip6_dst));
+
+ pseudo.length = ntohs(ip6.ip6_plen) + ip6_size;
- if(pseudo.length >= IP_MSS - sizeof(*hdr) - sizeof(*icmp))
- pseudo.length = IP_MSS - sizeof(*hdr) - sizeof(*icmp);
+ if(pseudo.length >= IP_MSS - ip6_size - icmp6_size)
+ pseudo.length = IP_MSS - ip6_size - icmp6_size;
/* Copy first part of original contents to ICMP message */
- memmove(((char *)icmp) + sizeof(*icmp), hdr, pseudo.length);
+ memmove(packet->data + ether_size + ip6_size + icmp6_size, packet->data + ether_size, 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_src, 16);
- memcpy(&hdr->ip6_src, &pseudo.ip6_dst, 16);
+ ip6.ip6_flow = htonl(0x60000000UL);
+ ip6.ip6_plen = htons(icmp6_size + pseudo.length);
+ ip6.ip6_nxt = IPPROTO_ICMPV6;
+ ip6.ip6_hlim = 255;
+ memcpy(&ip6.ip6_src, &pseudo.ip6_src, sizeof(ip6.ip6_src));
+ memcpy(&ip6.ip6_dst, &pseudo.ip6_dst, sizeof(ip6.ip6_dst));
/* Fill in ICMP header */
- icmp->icmp6_type = ICMP6_DST_UNREACH;
- icmp->icmp6_code = code;
- icmp->icmp6_cksum = 0;
+ icmp6.icmp6_type = ICMP6_DST_UNREACH;
+ icmp6.icmp6_code = code;
+ icmp6.icmp6_cksum = 0;
/* Create pseudo header */
- memcpy(&pseudo.ip6_src, &hdr->ip6_src, 16);
- memcpy(&pseudo.ip6_dst, &hdr->ip6_dst, 16);
- pseudo.length = htonl(sizeof(*icmp) + pseudo.length);
+ pseudo.length = htonl(icmp6_size + pseudo.length);
pseudo.next = htonl(IPPROTO_ICMPV6);
/* Generate checksum */
checksum = inet_checksum(&pseudo, sizeof(pseudo), ~0);
- checksum = inet_checksum(icmp, ntohl(pseudo.length), checksum);
+ checksum = inet_checksum(&icmp6, icmp6_size, checksum);
+ checksum = inet_checksum(packet->data + ether_size + ip6_size + icmp6_size, ntohl(pseudo.length) - icmp6_size, checksum);
+
+ icmp6.icmp6_cksum = checksum;
+
+ /* Copy structs on stack back to packet */
- icmp->icmp6_cksum = checksum;
+ memcpy(packet->data + ether_size, &ip6, ip6_size);
+ memcpy(packet->data + ether_size + ip6_size, &icmp6, icmp6_size);
- packet->len = 14 + sizeof(*hdr) + ntohl(pseudo.length);
+ packet->len = ether_size + ip6_size + ntohl(pseudo.length);
write_packet(packet);
}
-node_t *route_ipv6(vpn_packet_t *packet)
+static node_t *route_ipv6(vpn_packet_t *packet)
{
subnet_t *subnet;
cp();
- subnet = lookup_subnet_ipv6((ipv6_t *) & packet->data[38]);
+ subnet = lookup_subnet_ipv6((ipv6_t *) &packet->data[38]);
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(*(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]));
- }
+ ifdebug(TRAFFIC) logger(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 */
-void route_neighborsol(vpn_packet_t *packet)
+static void route_neighborsol(vpn_packet_t *packet)
{
- struct ip6_hdr *hdr;
- struct nd_neighbor_solicit *ns;
- struct nd_opt_hdr *opt;
+ struct ip6_hdr ip6;
+ struct nd_neighbor_solicit ns;
+ struct nd_opt_hdr opt;
subnet_t *subnet;
uint16_t checksum;
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));
+ /* Copy headers from packet to structs on the stack */
+
+ memcpy(&ip6, packet->data + ether_size, ip6_size);
+ memcpy(&ns, packet->data + ether_size + ip6_size, ns_size);
+ memcpy(&opt, packet->data + ether_size + ip6_size + ns_size, opt_size);
/* First, snatch the source address from the neighbor solicitation packet */
- memcpy(mymac.net.mac.address.x, packet->data + 6, 6);
+ if(overwrite_mac)
+ memcpy(mymac.x, packet->data + ETH_ALEN, ETH_ALEN);
/* 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) {
- if(debug_lvl > DEBUG_TRAFFIC) {
- syslog(LOG_WARNING, _("Cannot route packet: received unknown type neighbor solicitation request"));
- }
+ if(ns.nd_ns_hdr.icmp6_type != ND_NEIGHBOR_SOLICIT ||
+ opt.nd_opt_type != ND_OPT_SOURCE_LINKADDR) {
+ ifdebug(TRAFFIC) logger(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);
+ memcpy(&pseudo.ip6_src, &ip6.ip6_src, sizeof(ip6.ip6_src));
+ memcpy(&pseudo.ip6_dst, &ip6.ip6_dst, sizeof(ip6.ip6_dst));
+ pseudo.length = htonl(ns_size + opt_size + ETH_ALEN);
pseudo.next = htonl(IPPROTO_ICMPV6);
/* Generate checksum */
checksum = inet_checksum(&pseudo, sizeof(pseudo), ~0);
- checksum = inet_checksum(ns, sizeof(*ns) + 8, checksum);
+ checksum = inet_checksum(&ns, ns_size, checksum);
+ checksum = inet_checksum(&opt, opt_size, checksum);
if(checksum) {
- if(debug_lvl >= DEBUG_TRAFFIC)
- syslog(LOG_WARNING, _("Cannot route packet: checksum error for neighbor solicitation request"));
+ ifdebug(TRAFFIC) logger(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);
+ subnet = lookup_subnet_ipv6((ipv6_t *) &ns.nd_ns_target);
if(!subnet) {
- 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(((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]));
- }
+ ifdebug(TRAFFIC) logger(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;
}
/* 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(packet->data, packet->data + ETH_ALEN, ETH_ALEN); /* copy destination address */
+ packet->data[ETH_ALEN * 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(&ip6.ip6_src, &ns.nd_ns_target, sizeof(ip6.ip6_src)); /* swap destination and source protocol address */
+ memcpy(&ip6.ip6_dst, &ip6.ip6_src, sizeof(ip6.ip6_dst)); /* ... */
- memcpy((char *) opt + sizeof(*opt), packet->data + ETHER_ADDR_LEN, 6); /* add fake source hard addr */
+ memcpy(&opt + opt_size, packet->data + ETH_ALEN, ETH_ALEN); /* 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;
+ ns.nd_ns_cksum = 0;
+ ns.nd_ns_type = ND_NEIGHBOR_ADVERT;
+ ns.nd_ns_reserved = htonl(0x40000000UL); /* Set solicited flag */
+ 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);
+ memcpy(&pseudo.ip6_src, &ip6.ip6_src, sizeof(ip6.ip6_src));
+ memcpy(&pseudo.ip6_dst, &ip6.ip6_dst, sizeof(ip6.ip6_dst));
+ pseudo.length = htonl(ns_size + opt_size + ETH_ALEN);
pseudo.next = htonl(IPPROTO_ICMPV6);
/* Generate checksum */
checksum = inet_checksum(&pseudo, sizeof(pseudo), ~0);
- checksum = inet_checksum(ns, sizeof(*ns) + 8, checksum);
+ checksum = inet_checksum(&ns, ns_size, checksum);
+ checksum = inet_checksum(&opt, opt_size, checksum);
+
+ ns.nd_ns_hdr.icmp6_cksum = checksum;
+
+ /* Copy structs on stack back to packet */
- ns->nd_ns_hdr.icmp6_cksum = checksum;
+ memcpy(packet->data + ether_size, &ip6, ip6_size);
+ memcpy(packet->data + ether_size + ip6_size, &ns, ns_size);
+ memcpy(packet->data + ether_size + ip6_size + ns_size, &opt, opt_size);
write_packet(packet);
}
/* RFC 826 */
-void route_arp(vpn_packet_t *packet)
+static void route_arp(vpn_packet_t *packet)
{
- struct ether_arp *arp;
+ struct ether_arp arp;
subnet_t *subnet;
- uint8_t ipbuf[4];
+ struct in_addr addr;
cp();
/* First, snatch the source address from the ARP packet */
- memcpy(mymac.net.mac.address.x, packet->data + 6, 6);
+ if(overwrite_mac)
+ memcpy(mymac.x, packet->data + ETH_ALEN, ETH_ALEN);
- /* 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)
- */
+ /* Copy headers from packet to structs on the stack */
- arp = (struct ether_arp *)(packet->data + 14);
+ memcpy(&arp, packet->data + ether_size, arp_size);
/* 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) {
- if(debug_lvl > DEBUG_TRAFFIC) {
- syslog(LOG_WARNING, _("Cannot route packet: received unknown type ARP request"));
- }
+ if(ntohs(arp.arp_hrd) != ARPHRD_ETHER || ntohs(arp.arp_pro) != ETH_P_IP ||
+ arp.arp_hln != ETH_ALEN || arp.arp_pln != sizeof(addr) || ntohs(arp.arp_op) != ARPOP_REQUEST) {
+ ifdebug(TRAFFIC) logger(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);
+ 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]);
- }
-
+ ifdebug(TRAFFIC) logger(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;
}
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(packet->data, packet->data + ETH_ALEN, ETH_ALEN); /* copy destination address */
+ packet->data[ETH_ALEN * 2 - 1] ^= 0xFF; /* mangle source address so it looks like it's not from us */
+
+ memcpy(&addr, arp.arp_tpa, sizeof(addr)); /* save protocol addr */
+ memcpy(arp.arp_tpa, arp.arp_spa, sizeof(addr)); /* swap destination and source protocol address */
+ memcpy(arp.arp_spa, &addr, sizeof(addr)); /* ... */
- 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, ETH_ALEN); /* set target hard/proto addr */
+ memcpy(arp.arp_sha, packet->data + ETH_ALEN, ETH_ALEN); /* add fake source hard addr */
+ arp.arp_op = htons(ARPOP_REPLY);
- 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);
+ /* Copy structs on stack back to packet */
+
+ memcpy(packet->data + ether_size, &arp, arp_size);
write_packet(packet);
}
cp();
+ if(packet->len < ether_size) {
+ ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
+ return;
+ }
+
/* FIXME: multicast? */
switch (routing_mode) {
case RMODE_ROUTER:
type = ntohs(*((uint16_t *)(&packet->data[12])));
switch (type) {
- case 0x0800:
+ case ETH_P_IP:
+ if(packet->len < ether_size + ip_size) {
+ ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
+ return;
+ }
+
n = route_ipv4(packet);
break;
- case 0x86DD:
- if(packet->data[20] == IPPROTO_ICMPV6 && packet->data[54] == ND_NEIGHBOR_SOLICIT) {
+ case ETH_P_IPV6:
+ if(packet->len < ether_size + ip6_size) {
+ ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
+ return;
+ }
+
+ if(packet->data[20] == IPPROTO_ICMPV6 && packet->len >= ether_size + ip6_size + ns_size && packet->data[54] == ND_NEIGHBOR_SOLICIT) {
route_neighborsol(packet);
return;
}
n = route_ipv6(packet);
break;
- case 0x0806:
+ case ETH_P_ARP:
+ if(packet->len < ether_size + arp_size) {
+ ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
+ return;
+ }
+
route_arp(packet);
return;
default:
- if(debug_lvl >= DEBUG_TRAFFIC)
- syslog(LOG_WARNING, _("Cannot route packet: unknown type %hx"), type);
+ ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: unknown type %hx"), type);
return;
}
if(n)
void route_incoming(node_t *source, vpn_packet_t *packet)
{
+ if(packet->len < ether_size) {
+ ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
+ return;
+ }
+
switch (routing_mode) {
case RMODE_ROUTER:
{
type = ntohs(*((uint16_t *)(&packet->data[12])));
switch (type) {
- case 0x0800:
+ case ETH_P_IP:
+ if(packet->len < ether_size + ip_size) {
+ ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
+ return;
+ }
+
n = route_ipv4(packet);
break;
- case 0x86DD:
+ case ETH_P_IPV6:
+ if(packet->len < ether_size + ip6_size) {
+ ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
+ return;
+ }
+
n = route_ipv6(packet);
break;
if(n) {
if(n == myself) {
- memcpy(packet->data, mymac.net.mac.address.x, 6);
+ if(overwrite_mac)
+ memcpy(packet->data, mymac.x, ETH_ALEN);
write_packet(packet);
} else
send_packet(n, packet);