MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-
- $Id$
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "system.h"
/* RFC 1071 */
-static 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;
} else
return true;
}
+
+static void swap_mac_addresses(vpn_packet_t *packet) {
+ mac_t tmp;
+ memcpy(&tmp, &packet->data[0], sizeof tmp);
+ memcpy(&packet->data[0], &packet->data[6], sizeof tmp);
+ memcpy(&packet->data[6], &tmp, sizeof tmp);
+}
-static void learn_mac(mac_t *address)
-{
+static void learn_mac(mac_t *address) {
subnet_t *subnet;
avl_node_t *node;
connection_t *c;
subnet->expires = now + macexpire;
}
-void age_subnets(void)
-{
+void age_subnets(void) {
subnet_t *s;
connection_t *c;
avl_node_t *node, *next, *node2;
}
}
-static void route_mac(node_t *source, vpn_packet_t *packet)
-{
- subnet_t *subnet;
- mac_t dest;
-
- cp();
-
-
- /* Learn source address */
-
- if(source == myself) {
- mac_t src;
- memcpy(&src, &packet->data[6], sizeof src);
- learn_mac(&src);
- }
-
- /* Lookup destination address */
-
- memcpy(&dest, &packet->data[0], sizeof dest);
- subnet = lookup_subnet_mac(&dest);
-
- if(!subnet) {
- broadcast_packet(source, packet);
- return;
- }
-
- if(subnet->owner == source) {
- ifdebug(TRAFFIC) logger(LOG_WARNING, _("Packet looping back to %s (%s)!"), source->name, source->hostname);
- return;
- }
-
- send_packet(subnet->owner, packet);
-}
-
/* RFC 792 */
-static void route_ipv4_unreachable(node_t *source, vpn_packet_t *packet, uint8_t type, uint8_t code)
-{
+static void route_ipv4_unreachable(node_t *source, vpn_packet_t *packet, uint8_t type, uint8_t code) {
struct ip ip = {0};
struct icmp icmp = {0};
cp();
+ /* Swap Ethernet source and destination addresses */
+
+ swap_mac_addresses(packet);
+
/* Copy headers from packet into properly aligned structs on the stack */
memcpy(&ip, packet->data + ether_size, ip_size);
}
}
-static void route_ipv4_unicast(node_t *source, vpn_packet_t *packet)
-{
+static void route_ipv4_unicast(node_t *source, vpn_packet_t *packet) {
subnet_t *subnet;
node_t *via;
ipv4_t dest;
send_packet(subnet->owner, packet);
}
-static void route_ipv4(node_t *source, vpn_packet_t *packet)
-{
+static void route_ipv4(node_t *source, vpn_packet_t *packet) {
cp();
if(!checklength(source, packet, ether_size + ip_size))
/* RFC 2463 */
-static void route_ipv6_unreachable(node_t *source, vpn_packet_t *packet, uint8_t type, uint8_t code)
-{
+static void route_ipv6_unreachable(node_t *source, vpn_packet_t *packet, uint8_t type, uint8_t code) {
struct ip6_hdr ip6;
struct icmp6_hdr icmp6 = {0};
uint16_t checksum;
cp();
+ /* Swap Ethernet source and destination addresses */
+
+ swap_mac_addresses(packet);
+
/* Copy headers from packet to structs on the stack */
memcpy(&ip6, packet->data + ether_size, ip6_size);
send_packet(source, packet);
}
-static void route_ipv6_unicast(node_t *source, vpn_packet_t *packet)
-{
+static void route_ipv6_unicast(node_t *source, vpn_packet_t *packet) {
subnet_t *subnet;
node_t *via;
ipv6_t dest;
/* RFC 2461 */
-static void route_neighborsol(node_t *source, vpn_packet_t *packet)
-{
+static void route_neighborsol(node_t *source, vpn_packet_t *packet) {
struct ip6_hdr ip6;
struct nd_neighbor_solicit ns;
struct nd_opt_hdr opt;
send_packet(source, packet);
}
-static void route_ipv6(node_t *source, vpn_packet_t *packet)
-{
+static void route_ipv6(node_t *source, vpn_packet_t *packet) {
cp();
if(!checklength(source, packet, ether_size + ip6_size))
/* RFC 826 */
-static void route_arp(node_t *source, vpn_packet_t *packet)
-{
+static void route_arp(node_t *source, vpn_packet_t *packet) {
struct ether_arp arp;
subnet_t *subnet;
struct in_addr addr;
send_packet(source, packet);
}
-void route(node_t *source, vpn_packet_t *packet)
-{
+static void route_mac(node_t *source, vpn_packet_t *packet) {
+ subnet_t *subnet;
+ mac_t dest;
+
+ cp();
+
+
+ /* Learn source address */
+
+ if(source == myself) {
+ mac_t src;
+ memcpy(&src, &packet->data[6], sizeof src);
+ learn_mac(&src);
+ }
+
+ /* Lookup destination address */
+
+ memcpy(&dest, &packet->data[0], sizeof dest);
+ subnet = lookup_subnet_mac(&dest);
+
+ if(!subnet) {
+ broadcast_packet(source, packet);
+ return;
+ }
+
+ if(subnet->owner == source) {
+ ifdebug(TRAFFIC) logger(LOG_WARNING, _("Packet looping back to %s (%s)!"), source->name, source->hostname);
+ return;
+ }
+
+ // Handle packets larger than PMTU
+
+ node_t *via = (subnet->owner->via == myself) ? subnet->owner->nexthop : subnet->owner->via;
+
+ if(via && packet->len > via->mtu && via != myself) {
+ ifdebug(TRAFFIC) logger(LOG_INFO, _("Packet for %s (%s) length %d larger than MTU %d"), subnet->owner->name, subnet->owner->hostname, packet->len, via->mtu);
+ uint16_t type = packet->data[12] << 8 | packet->data[13];
+ if(type == ETH_P_IP) {
+ if(packet->data[20] & 0x40) {
+ packet->len = via->mtu;
+ route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED);
+ } else {
+ fragment_ipv4_packet(via, packet);
+ }
+ return;
+ } else if(type == ETH_P_IPV6) {
+ packet->len = via->mtu;
+ route_ipv6_unreachable(source, packet, ICMP6_PACKET_TOO_BIG, 0);
+ return;
+ }
+ }
+
+ send_packet(subnet->owner, packet);
+}
+
+
+void route(node_t *source, vpn_packet_t *packet) {
cp();
if(!checklength(source, packet, ether_size))
switch (routing_mode) {
case RMODE_ROUTER:
{
- uint16_t type;
+ uint16_t type = packet->data[12] << 8 | packet->data[13];
- type = ntohs(*((uint16_t *)(&packet->data[12])));
switch (type) {
case ETH_P_ARP:
route_arp(source, packet);
projects / oweals / tinc.git / blobdiff