X-Git-Url: http://git.meshlink.io/?p=meshlink;a=blobdiff_plain;f=src%2Froute.c;h=ee36a9bfe4b17c8289d85053312a7d44ed2692c3;hp=f18bd268305a520cc3ba7c1d22e6aacf7fa2c15b;hb=963c5055505f2fc117cd5efa06eaa02c9b2bf85d;hpb=103543aa2c15d9f1e2aa313a2e593a7524cce484

diff --git a/src/route.c b/src/route.c
index f18bd268..ee36a9bf 100644
--- a/src/route.c
+++ b/src/route.c
@@ -1,7 +1,6 @@
 /*
     route.c -- routing
-    Copyright (C) 2000-2005 Ivo Timmermans,
-                  2000-2010 Guus Sliepen <guus@tinc-vpn.org>
+    Copyright (C) 2014 Guus Sliepen <guus@meshlink.io>
 
     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
@@ -20,883 +19,74 @@
 
 #include "system.h"
 
-#include "splay_tree.h"
-#include "connection.h"
-#include "ethernet.h"
-#include "ipv4.h"
-#include "ipv6.h"
 #include "logger.h"
+#include "meshlink_internal.h"
 #include "net.h"
-#include "protocol.h"
 #include "route.h"
-#include "subnet.h"
 #include "utils.h"
 
-rmode_t routing_mode = RMODE_ROUTER;
-fmode_t forwarding_mode = FMODE_INTERNAL;
-bool directonly = false;
-bool priorityinheritance = false;
-int macexpire = 600;
-bool overwrite_mac = false;
-mac_t mymac = {{0xFE, 0xFD, 0, 0, 0, 0}};
+static bool checklength(node_t *source, vpn_packet_t *packet, uint16_t length) {
+	assert(length);
 
-/* Sizes of various headers */
-
-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);
-#define max(a, b) ((a) > (b) ? (a) : (b))
-
-static struct event age_subnets_event;
-
-/* 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 += *(uint8_t *)p;
-
-	while(checksum >> 16)
-		checksum = (checksum & 0xFFFF) + (checksum >> 16);
-
-	return ~checksum;
-}
-
-static bool ratelimit(int frequency) {
-	static time_t lasttime = 0;
-	static int count = 0;
-	time_t now = time(NULL);
-	
-	if(lasttime == now) {
-		if(++count > frequency)
-			return true;
-	} else {
-		lasttime = now;
-		count = 0;
-	}
-
-	return false;
-}
-
-static bool checklength(node_t *source, vpn_packet_t *packet, length_t length) {
 	if(packet->len < length) {
-		ifdebug(TRAFFIC) logger(LOG_WARNING, "Got too short packet from %s (%s)", source->name, source->hostname);
+		logger(source->mesh, MESHLINK_WARNING, "Got too short packet from %s", source->name);
 		return false;
-	} else
-		return true;
-}
-
-static void clamp_mss(const node_t *source, const node_t *via, vpn_packet_t *packet) {
-	if(!source || !via || !(via->options & OPTION_CLAMP_MSS))
-		return;
-
-	uint16_t mtu = source->mtu;
-	if(via != myself && via->mtu < mtu)
-		mtu = via->mtu;
-
-	/* Find TCP header */
-	int start = 0;
-	uint16_t type = packet->data[12] << 8 | packet->data[13];
-
-	if(type == ETH_P_IP && packet->data[23] == 6)
-		start = 14 + (packet->data[14] & 0xf) * 4;
-	else if(type == ETH_P_IPV6 && packet->data[20] == 6)
-		start = 14 + 40;
-
-	if(!start || packet->len <= start + 20)
-		return;
-
-	/* Use data offset field to calculate length of options field */
-	int len = ((packet->data[start + 12] >> 4) - 5) * 4;
-
-	if(packet->len < start + 20 + len)
-		return;
-
-	/* Search for MSS option header */
-	for(int i = 0; i < len;) {
-		if(packet->data[start + 20 + i] == 0)
-			break;
-
-		if(packet->data[start + 20 + i] == 1) {
-			i++;
-			continue;
-		}
-
-		if(i > len - 2 || i > len - packet->data[start + 21 + i])
-			break;
-
-		if(packet->data[start + 20 + i] != 2) {
-			if(packet->data[start + 21 + i] < 2)
-				break;
-			i += packet->data[start + 21 + i];
-			continue;
-		}
-
-		if(packet->data[start + 21] != 4)
-			break;
-
-		/* Found it */
-		uint16_t oldmss = packet->data[start + 22 + i] << 8 | packet->data[start + 23 + i];
-		uint16_t newmss = mtu - start - 20;
-		uint16_t csum = packet->data[start + 16] << 8 | packet->data[start + 17];
-
-		if(oldmss <= newmss)
-			break;
-		
-		ifdebug(TRAFFIC) logger(LOG_INFO, "Clamping MSS of packet from %s to %s to %d", source->name, via->name, newmss);
-
-		/* Update the MSS value and the checksum */
-		packet->data[start + 22 + i] = newmss >> 8;
-		packet->data[start + 23 + i] = newmss & 0xff;
-		csum ^= 0xffff;
-		csum -= oldmss;
-		csum += newmss;
-		csum ^= 0xffff;
-		packet->data[start + 16] = csum >> 8;
-		packet->data[start + 17] = csum & 0xff;
-		break;
-	}
-}
-
-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 age_subnets(int fd, short events, void *data) {
-	subnet_t *s;
-	connection_t *c;
-	splay_node_t *node, *next, *node2;
-	bool left = false;
-	time_t now = time(NULL);
-
-	for(node = myself->subnet_tree->head; node; node = next) {
-		next = node->next;
-		s = node->data;
-		if(s->expires && s->expires < now) {
-			ifdebug(TRAFFIC) {
-				char netstr[MAXNETSTR];
-				if(net2str(netstr, sizeof netstr, s))
-					logger(LOG_INFO, "Subnet %s expired", netstr);
-			}
-
-			for(node2 = connection_tree->head; node2; node2 = node2->next) {
-				c = node2->data;
-				if(c->status.active)
-					send_del_subnet(c, s);
-			}
-
-			subnet_del(myself, s);
-		} else {
-			if(s->expires)
-				left = true;
-		}
-	}
-
-	if(left)
-		event_add(&age_subnets_event, &(struct timeval){10, 0});
-}
-
-static void learn_mac(mac_t *address) {
-	subnet_t *subnet;
-	splay_node_t *node;
-	connection_t *c;
-
-	subnet = lookup_subnet_mac(myself, address);
-
-	/* If we don't know this MAC address yet, store it */
-
-	if(!subnet) {
-		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]);
-
-		subnet = new_subnet();
-		subnet->type = SUBNET_MAC;
-		subnet->expires = time(NULL) + macexpire;
-		subnet->net.mac.address = *address;
-		subnet->weight = 10;
-		subnet_add(myself, subnet);
-		subnet_update(myself, subnet, true);
-
-		/* And tell all other tinc daemons it's our MAC */
-
-		for(node = connection_tree->head; node; node = node->next) {
-			c = node->data;
-			if(c->status.active)
-				send_add_subnet(c, subnet);
-		}
-
-		if(!timeout_initialized(&age_subnets_event))
-			timeout_set(&age_subnets_event, age_subnets, NULL);
-		event_add(&age_subnets_event, &(struct timeval){10, 0});
 	} else {
-		if(subnet->expires)
-			subnet->expires = time(NULL) + macexpire;
+		return true;
 	}
 }
 
-/* RFC 792 */
-
-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};
-	
-	struct in_addr ip_src;
-	struct in_addr ip_dst;
-	uint32_t oldlen;
-
-	if(ratelimit(3))
-		return;
-	
-	/* 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);
-
-	/* Remember original source and destination */
-	
-	ip_src = ip.ip_src;
-	ip_dst = ip.ip_dst;
-
-	oldlen = packet->len - ether_size;
-
-	if(type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED)
-		icmp.icmp_nextmtu = htons(packet->len - ether_size);
-
-	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(packet->data + ether_size + ip_size + icmp_size, packet->data + ether_size, oldlen);
-
-	/* Fill in IPv4 header */
-	
-	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;
-	ip.ip_src = ip_dst;
-	ip.ip_dst = ip_src;
-
-	ip.ip_sum = inet_checksum(&ip, ip_size, ~0);
-	
-	/* Fill in ICMP header */
-	
-	icmp.icmp_type = type;
-	icmp.icmp_code = code;
-	icmp.icmp_cksum = 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 = ether_size + ip_size + icmp_size + oldlen;
-
-	send_packet(source, packet);
-}
-
-/* RFC 791 */
+void route(meshlink_handle_t *mesh, node_t *source, vpn_packet_t *packet) {
+	assert(source);
 
-static void fragment_ipv4_packet(node_t *dest, vpn_packet_t *packet) {
-	struct ip ip;
-	vpn_packet_t fragment;
-	int len, maxlen, todo;
-	uint8_t *offset;
-	uint16_t ip_off, origf;
-	
-	memcpy(&ip, packet->data + ether_size, ip_size);
-	fragment.priority = packet->priority;
+	// TODO: route on name or key
 
-	if(ip.ip_hl != ip_size / 4)
-		return;
-	
-	todo = ntohs(ip.ip_len) - ip_size;
+	meshlink_packethdr_t *hdr = (meshlink_packethdr_t *) packet->data;
+	node_t *dest = lookup_node(mesh, (char *)hdr->destination);
+	logger(mesh, MESHLINK_DEBUG, "Routing packet from \"%s\" to \"%s\"\n", hdr->source, hdr->destination);
 
-	if(ether_size + ip_size + todo != packet->len) {
-		ifdebug(TRAFFIC) logger(LOG_WARNING, "Length of packet (%d) doesn't match length in IPv4 header (%zd)", packet->len, ether_size + ip_size + todo);
+	//Check Length
+	if(!checklength(source, packet, sizeof(*hdr))) {
 		return;
 	}
 
-	ifdebug(TRAFFIC) logger(LOG_INFO, "Fragmenting packet of %d bytes to %s (%s)", packet->len, dest->name, dest->hostname);
-
-	offset = packet->data + ether_size + ip_size;
-	maxlen = (dest->mtu - ether_size - ip_size) & ~0x7;
-	ip_off = ntohs(ip.ip_off);
-	origf = ip_off & ~IP_OFFMASK;
-	ip_off &= IP_OFFMASK;
-	
-	while(todo) {
-		len = todo > maxlen ? maxlen : todo;
-		memcpy(fragment.data + ether_size + ip_size, offset, len);
-		todo -= len;
-		offset += len;
-
-		ip.ip_len = htons(ip_size + len);
-		ip.ip_off = htons(ip_off | origf | (todo ? IP_MF : 0));
-		ip.ip_sum = 0;
-		ip.ip_sum = inet_checksum(&ip, ip_size, ~0);
-		memcpy(fragment.data, packet->data, ether_size);
-		memcpy(fragment.data + ether_size, &ip, ip_size);
-		fragment.len = ether_size + ip_size + len;
-
-		send_packet(dest, &fragment);
-
-		ip_off += len / 8;
-	}	
-}
-
-static void route_ipv4_unicast(node_t *source, vpn_packet_t *packet) {
-	subnet_t *subnet;
-	node_t *via;
-	ipv4_t dest;
-
-	memcpy(&dest, &packet->data[30], sizeof dest);
-	subnet = lookup_subnet_ipv4(&dest);
-
-	if(!subnet) {
-		ifdebug(TRAFFIC) logger(LOG_WARNING, "Cannot route packet from %s (%s): unknown IPv4 destination address %d.%d.%d.%d",
-				source->name, source->hostname,
-				dest.x[0],
-				dest.x[1],
-				dest.x[2],
-				dest.x[3]);
-
-		route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_NET_UNKNOWN);
-		return;
-	}
-	
-	if(subnet->owner == source) {
-		ifdebug(TRAFFIC) logger(LOG_WARNING, "Packet looping back to %s (%s)!", source->name, source->hostname);
+	if(dest == NULL) {
+		//Lookup failed
+		logger(mesh, MESHLINK_WARNING, "Can't lookup the destination of a packet in the route() function. This should never happen!\n");
+		logger(mesh, MESHLINK_WARNING, "Destination was: %s\n", hdr->destination);
 		return;
 	}
 
-	if(!subnet->owner->status.reachable)
-		return route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_NET_UNREACH);
+	if(dest == mesh->self) {
+		const void *payload = packet->data + sizeof(*hdr);
+		size_t len = packet->len - sizeof(*hdr);
 
-	if(forwarding_mode == FMODE_OFF && source != myself && subnet->owner != myself)
-		return route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_NET_ANO);
+		char hex[len * 2 + 1];
 
-	if(priorityinheritance)
-		packet->priority = packet->data[15];
-
-	via = (subnet->owner->via == myself) ? subnet->owner->nexthop : subnet->owner->via;
-	
-	if(directonly && subnet->owner != via)
-		return route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_NET_ANO);
-
-	if(via && packet->len > max(via->mtu, 590) && 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);
-		if(packet->data[20] & 0x40) {
-			packet->len = max(via->mtu, 590);
-			route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED);
-		} else {
-			fragment_ipv4_packet(via, packet);
+		if(mesh->log_level <= MESHLINK_DEBUG) {
+			bin2hex(payload, hex, len);        // don't do this unless it's going to be logged
 		}
 
-		return;
-	}
-
-	clamp_mss(source, via, packet);
- 
-	send_packet(subnet->owner, packet);
-}
-
-static void route_ipv4(node_t *source, vpn_packet_t *packet) {
-	if(!checklength(source, packet, ether_size + ip_size))
-		return;
-
-	if(((packet->data[30] & 0xf0) == 0xe0) || (
-			packet->data[30] == 255 &&
-			packet->data[31] == 255 &&
-			packet->data[32] == 255 &&
-			packet->data[33] == 255))
-		broadcast_packet(source, packet);
-	else
-		route_ipv4_unicast(source, packet);
-}
-
-/* RFC 2463 */
-
-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;	
-
-	struct {
-		struct in6_addr ip6_src;	/* source address */
-		struct in6_addr ip6_dst;	/* destination address */
-		uint32_t length;
-		uint32_t next;
-	} pseudo;
-
-	if(ratelimit(3))
-		return;
-	
-	/* 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);
-
-	/* Remember original source and destination */
-	
-	pseudo.ip6_src = ip6.ip6_dst;
-	pseudo.ip6_dst = ip6.ip6_src;
-
-	pseudo.length = packet->len - ether_size;
-
-	if(type == ICMP6_PACKET_TOO_BIG)
-		icmp6.icmp6_mtu = htonl(pseudo.length);
-	
-	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(packet->data + ether_size + ip6_size + icmp6_size, packet->data + ether_size, pseudo.length);
-
-	/* Fill in IPv6 header */
-	
-	ip6.ip6_flow = htonl(0x60000000UL);
-	ip6.ip6_plen = htons(icmp6_size + pseudo.length);
-	ip6.ip6_nxt = IPPROTO_ICMPV6;
-	ip6.ip6_hlim = 255;
-	ip6.ip6_src = pseudo.ip6_src;
-	ip6.ip6_dst = pseudo.ip6_dst;
-
-	/* Fill in ICMP header */
-	
-	icmp6.icmp6_type = type;
-	icmp6.icmp6_code = code;
-	icmp6.icmp6_cksum = 0;
-
-	/* Create pseudo header */
-		
-	pseudo.length = htonl(icmp6_size + pseudo.length);
-	pseudo.next = htonl(IPPROTO_ICMPV6);
-
-	/* Generate checksum */
-	
-	checksum = inet_checksum(&pseudo, sizeof pseudo, ~0);
-	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 */
-
-	memcpy(packet->data + ether_size, &ip6, ip6_size);
-	memcpy(packet->data + ether_size + ip6_size, &icmp6, icmp6_size);
-	
-	packet->len = ether_size + ip6_size + ntohl(pseudo.length);
-	
-	send_packet(source, packet);
-}
-
-static void route_ipv6_unicast(node_t *source, vpn_packet_t *packet) {
-	subnet_t *subnet;
-	node_t *via;
-	ipv6_t dest;
-
-	memcpy(&dest, &packet->data[38], sizeof dest);
-	subnet = lookup_subnet_ipv6(&dest);
-
-	if(!subnet) {
-		ifdebug(TRAFFIC) logger(LOG_WARNING, "Cannot route packet from %s (%s): unknown IPv6 destination address %hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx",
-				source->name, source->hostname,
-				ntohs(dest.x[0]),
-				ntohs(dest.x[1]),
-				ntohs(dest.x[2]),
-				ntohs(dest.x[3]),
-				ntohs(dest.x[4]),
-				ntohs(dest.x[5]),
-				ntohs(dest.x[6]),
-				ntohs(dest.x[7]));
-
-		route_ipv6_unreachable(source, packet, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_ADDR);
-		return;
-	}
-
-	if(subnet->owner == source) {
-		ifdebug(TRAFFIC) logger(LOG_WARNING, "Packet looping back to %s (%s)!", source->name, source->hostname);
-		return;
-	}
-
-	if(!subnet->owner->status.reachable)
-		return route_ipv6_unreachable(source, packet, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOROUTE);
-
-	if(forwarding_mode == FMODE_OFF && source != myself && subnet->owner != myself)
-		return route_ipv6_unreachable(source, packet, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_ADMIN);
-
-	via = (subnet->owner->via == myself) ? subnet->owner->nexthop : subnet->owner->via;
-	
-	if(directonly && subnet->owner != via)
-		return route_ipv6_unreachable(source, packet, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_ADMIN);
-
-	if(via && packet->len > max(via->mtu, 1294) && 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);
-		packet->len = max(via->mtu, 1294);
-		route_ipv6_unreachable(source, packet, ICMP6_PACKET_TOO_BIG, 0);
-		return;
-	}
-
-	clamp_mss(source, via, packet);
- 
-	send_packet(subnet->owner, packet);
-}
-
-/* RFC 2461 */
-
-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;
-	subnet_t *subnet;
-	uint16_t checksum;
-	bool has_opt;
-
-	struct {
-		struct in6_addr ip6_src;	/* source address */
-		struct in6_addr ip6_dst;	/* destination address */
-		uint32_t length;
-		uint32_t next;
-	} pseudo;
-
-	if(!checklength(source, packet, ether_size + ip6_size + ns_size))
-		return;
-	
-	has_opt = packet->len >= ether_size + ip6_size + ns_size + opt_size + ETH_ALEN;
-	
-	if(source != myself) {
-		ifdebug(TRAFFIC) logger(LOG_WARNING, "Got neighbor solicitation request from %s (%s) while in router mode!", source->name, source->hostname);
-		return;
-	}
-
-	/* 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);
-	if(has_opt)
-		memcpy(&opt, packet->data + ether_size + ip6_size + ns_size, opt_size);
-
-	/* First, snatch the source address from the neighbor solicitation packet */
-
-	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 ||
-	   (has_opt && 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 */
-
-	pseudo.ip6_src = ip6.ip6_src;
-	pseudo.ip6_dst = ip6.ip6_dst;
-	if(has_opt)
-		pseudo.length = htonl(ns_size + opt_size + ETH_ALEN);
-	else
-		pseudo.length = htonl(ns_size);
-	pseudo.next = htonl(IPPROTO_ICMPV6);
-
-	/* Generate checksum */
-
-	checksum = inet_checksum(&pseudo, sizeof pseudo, ~0);
-	checksum = inet_checksum(&ns, ns_size, checksum);
-	if(has_opt) {
-		checksum = inet_checksum(&opt, opt_size, checksum);
-		checksum = inet_checksum(packet->data + ether_size + ip6_size + ns_size + opt_size, ETH_ALEN, checksum);
-	}
-
-	if(checksum) {
-		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);
-
-	if(!subnet) {
-		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;
-	}
-
-	/* Check if it is for our own subnet */
-
-	if(subnet->owner == myself)
-		return;					/* silently ignore */
-
-	/* Create neighbor advertation reply */
-
-	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 */
-
-	ip6.ip6_dst = ip6.ip6_src;			/* swap destination and source protocoll address */
-	ip6.ip6_src = ns.nd_ns_target;
-
-	if(has_opt)
-		memcpy(packet->data + ether_size + ip6_size + ns_size + opt_size, packet->data + ETH_ALEN, ETH_ALEN);	/* add fake source hard addr */
-
-	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 */
-
-	pseudo.ip6_src = ip6.ip6_src;
-	pseudo.ip6_dst = ip6.ip6_dst;
-	if(has_opt)
-		pseudo.length = htonl(ns_size + opt_size + ETH_ALEN);
-	else
-		pseudo.length = htonl(ns_size);
-	pseudo.next = htonl(IPPROTO_ICMPV6);
-
-	/* Generate checksum */
-
-	checksum = inet_checksum(&pseudo, sizeof pseudo, ~0);
-	checksum = inet_checksum(&ns, ns_size, checksum);
-	if(has_opt) {
-		checksum = inet_checksum(&opt, opt_size, checksum);
-		checksum = inet_checksum(packet->data + ether_size + ip6_size + ns_size + opt_size, ETH_ALEN, checksum);
-	}
-
-	ns.nd_ns_hdr.icmp6_cksum = checksum;
-
-	/* Copy structs on stack back to packet */
-
-	memcpy(packet->data + ether_size, &ip6, ip6_size);
-	memcpy(packet->data + ether_size + ip6_size, &ns, ns_size);
-	if(has_opt)
-		memcpy(packet->data + ether_size + ip6_size + ns_size, &opt, opt_size);
-
-	send_packet(source, packet);
-}
-
-static void route_ipv6(node_t *source, vpn_packet_t *packet) {
-	if(!checklength(source, packet, ether_size + ip6_size))
-		return;
-
-	if(packet->data[20] == IPPROTO_ICMPV6 && checklength(source, packet, ether_size + ip6_size + icmp6_size) && packet->data[54] == ND_NEIGHBOR_SOLICIT) {
-		route_neighborsol(source, packet);
-		return;
-	}
-
-	if(packet->data[38] == 255)
-		broadcast_packet(source, packet);
-	else
-		route_ipv6_unicast(source, packet);
-}
-
-/* RFC 826 */
-
-static void route_arp(node_t *source, vpn_packet_t *packet) {
-	struct ether_arp arp;
-	subnet_t *subnet;
-	struct in_addr addr;
-
-	if(!checklength(source, packet, ether_size + arp_size))
-		return;
-
-	if(source != myself) {
-		ifdebug(TRAFFIC) logger(LOG_WARNING, "Got ARP request from %s (%s) while in router mode!", source->name, source->hostname);
-		return;
-	}
-
-	/* First, snatch the source address from the ARP packet */
-
-	if(overwrite_mac)
-		memcpy(mymac.x, packet->data + ETH_ALEN, ETH_ALEN);
-
-	/* Copy headers from packet to structs on the stack */
-
-	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) != 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);
-
-	if(!subnet) {
-		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;
-	}
-
-	/* Check if it is for our own subnet */
-
-	if(subnet->owner == myself)
-		return;					/* silently ignore */
-
-	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);	/* ... */
+		logger(mesh, MESHLINK_DEBUG, "I received a packet for me with payload: %s\n", hex);
 
-	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);
-
-	/* Copy structs on stack back to packet */
-
-	memcpy(packet->data + ether_size, &arp, arp_size);
-
-	send_packet(source, packet);
-}
-
-static void route_mac(node_t *source, vpn_packet_t *packet) {
-	subnet_t *subnet;
-	mac_t dest;
-
-	/* 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(NULL, &dest);
-
-	if(!subnet) {
-		broadcast_packet(source, packet);
-		return;
-	}
+		if(mesh->receive_cb) {
+			mesh->receive_cb(mesh, (meshlink_node_t *)source, payload, len);
+		}
 
-	if(subnet->owner == source) {
-		ifdebug(TRAFFIC) logger(LOG_WARNING, "Packet looping back to %s (%s)!", source->name, source->hostname);
 		return;
 	}
 
-	if(forwarding_mode == FMODE_OFF && source != myself && subnet->owner != myself)
-		return;
-
-	// Handle packets larger than PMTU
-
-	node_t *via = (subnet->owner->via == myself) ? subnet->owner->nexthop : subnet->owner->via;
-
-	if(directonly && subnet->owner != via)
+	if(!dest->status.reachable) {
+		//TODO: check what to do here, not just print a warning
+		logger(mesh, MESHLINK_WARNING, "The destination of a packet in the route() function is unreachable. Dropping packet.\n");
 		return;
-	
-	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 && packet->len > 590) {
-			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 > 1294) {
-			packet->len = via->mtu;
-			route_ipv6_unreachable(source, packet, ICMP6_PACKET_TOO_BIG, 0);
-			return;
-		}
 	}
 
-	clamp_mss(source, via, packet);
- 
-	send_packet(subnet->owner, packet);
-}
-
-void route(node_t *source, vpn_packet_t *packet) {
-	if(forwarding_mode == FMODE_KERNEL && source != myself) {
-		send_packet(myself, packet);
+	if(dest == source) {
+		logger(mesh, MESHLINK_ERROR, "Routing loop for packet from %s!", source->name);
 		return;
 	}
 
-	if(!checklength(source, packet, ether_size))
-		return;
-
-	switch (routing_mode) {
-		case RMODE_ROUTER:
-			{
-				uint16_t type = packet->data[12] << 8 | packet->data[13];
-
-				switch (type) {
-					case ETH_P_ARP:
-						route_arp(source, packet);
-						break;
-
-					case ETH_P_IP:
-						route_ipv4(source, packet);
-						break;
-
-					case ETH_P_IPV6:
-						route_ipv6(source, packet);
-						break;
-
-					default:
-						ifdebug(TRAFFIC) logger(LOG_WARNING, "Cannot route packet from %s (%s): unknown type %hx", source->name, source->hostname, type);
-						break;
-				}
-			}
-			break;
-
-		case RMODE_SWITCH:
-			route_mac(source, packet);
-			break;
-
-		case RMODE_HUB:
-			broadcast_packet(source, packet);
-			break;
-	}
+	send_packet(mesh, dest, packet);
+	return;
 }