X-Git-Url: https://git.librecmc.org/?p=oweals%2Ftinc.git;a=blobdiff_plain;f=src%2Froute.c;h=8f238e2cca36ad356206b338490cdbe3b5512ba4;hp=6d391cdf4a232fab65f7108ced4c84655b1e9007;hb=aebc97a77f37ec63fbd36721f9b284c975e54270;hpb=5a1406adefd8b51981af0da5ac0ebec830eb43b4

diff --git a/src/route.c b/src/route.c
index 6d391cd..8f238e2 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 1.1.2.70 2003/12/12 19:52:25 guus Exp $
+    $Id: route.c,v 1.1.2.75 2003/12/24 10:48:15 guus Exp $
 */
 
 #include "system.h"
@@ -53,7 +53,6 @@
 rmode_t routing_mode = RMODE_ROUTER;
 bool priorityinheritance = false;
 int macexpire = 600;
-int multicastexpire = 375;
 bool overwrite_mac = false;
 mac_t mymac = {{0xFE, 0xFD, 0, 0, 0, 0}};
 
@@ -70,7 +69,7 @@ static const size_t opt_size = sizeof(struct nd_opt_hdr);
 
 /* RFC 1071 */
 
-static uint16_t inet_checksum(void *data, int len, uint16_t prevsum)
+static __inline__ uint16_t inet_checksum(void *data, int len, uint16_t prevsum)
 {
 	uint16_t *p = data;
 	uint32_t checksum = prevsum ^ 0xFFFF;
@@ -89,7 +88,7 @@ static uint16_t inet_checksum(void *data, int len, uint16_t prevsum)
 	return ~checksum;
 }
 
-static bool ratelimit(int frequency) {
+static __inline__ bool ratelimit(int frequency) {
 	static time_t lasttime = 0;
 	static int count = 0;
 	
@@ -104,7 +103,7 @@ static bool ratelimit(int frequency) {
 	return false;
 }
 
-static bool checklength(node_t *source, vpn_packet_t *packet, length_t length) {
+static __inline__ 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);
 		return false;
@@ -112,7 +111,7 @@ static bool checklength(node_t *source, vpn_packet_t *packet, length_t length) {
 		return true;
 }
 	
-static void learn_mac(mac_t *address)
+static __inline__ void learn_mac(mac_t *address)
 {
 	subnet_t *subnet;
 	avl_node_t *node;
@@ -177,7 +176,7 @@ void age_subnets(void)
 	}
 }
 
-static void route_mac(node_t *source, vpn_packet_t *packet)
+static __inline__ void route_mac(node_t *source, vpn_packet_t *packet)
 {
 	subnet_t *subnet;
 
@@ -207,7 +206,7 @@ static void route_mac(node_t *source, vpn_packet_t *packet)
 
 /* RFC 792 */
 
-static void route_ipv4_unreachable(node_t *source, vpn_packet_t *packet, 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};
@@ -232,6 +231,9 @@ static void route_ipv4_unreachable(node_t *source, vpn_packet_t *packet, uint8_t
 
 	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;
 	
@@ -257,7 +259,7 @@ static void route_ipv4_unreachable(node_t *source, vpn_packet_t *packet, uint8_t
 	
 	/* Fill in ICMP header */
 	
-	icmp.icmp_type = ICMP_DEST_UNREACH;
+	icmp.icmp_type = type;
 	icmp.icmp_code = code;
 	icmp.icmp_cksum = 0;
 	
@@ -270,13 +272,66 @@ static void route_ipv4_unreachable(node_t *source, vpn_packet_t *packet, uint8_t
 	memcpy(packet->data + ether_size + ip_size, &icmp, icmp_size);
 	
 	packet->len = ether_size + ip_size + icmp_size + oldlen;
-	
+
 	send_packet(source, packet);
 }
 
-static void route_ipv4_unicast(node_t *source, vpn_packet_t *packet)
+/* RFC 791 */
+
+static __inline__ 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;
+	
+	cp();
+
+	memcpy(&ip, packet->data + ether_size, ip_size);
+	fragment.priority = packet->priority;
+
+	if(ip.ip_hl != ip_size / 4)
+		return;
+	
+	todo = ntohs(ip.ip_len) - ip_size;
+
+	if(ether_size + ip_size + todo != packet->len) {
+		ifdebug(TRAFFIC) logger(LOG_WARNING, _("Length of packet (%d) doesn't match length in IPv4 header (%d)"), packet->len, ether_size + ip_size + todo);
+		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 __inline__ void route_ipv4_unicast(node_t *source, vpn_packet_t *packet)
 {
 	subnet_t *subnet;
+	node_t *via;
 
 	cp();
 
@@ -290,7 +345,7 @@ static void route_ipv4_unicast(node_t *source, vpn_packet_t *packet)
 				packet->data[32],
 				packet->data[33]);
 
-		route_ipv4_unreachable(source, packet, ICMP_NET_UNKNOWN);
+		route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_NET_UNKNOWN);
 		return;
 	}
 	
@@ -300,34 +355,41 @@ static void route_ipv4_unicast(node_t *source, vpn_packet_t *packet)
 	}
 
 	if(!subnet->owner->status.reachable)
-		route_ipv4_unreachable(source, packet, ICMP_NET_UNREACH);
+		route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_NET_UNREACH);
 
 	if(priorityinheritance)
 		packet->priority = packet->data[15];
 
+	via = (subnet->owner->via == myself) ? subnet->owner->nexthop : subnet->owner->via;
+	
+	if(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);
+		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;
+	}
+
 	send_packet(subnet->owner, packet);
 }
 
-static void route_ipv4(node_t *source, vpn_packet_t *packet)
+static __inline__ void route_ipv4(node_t *source, vpn_packet_t *packet)
 {
 	cp();
 
 	if(!checklength(source, packet, ether_size + ip_size))
 		return;
 
-#if 0
-	if(packet->data[30] & 0xf0 == 0xe0) {
-		route_ipv4_multicast(source, packet);
-		return;
-	}
-#endif
-
 	route_ipv4_unicast(source, packet);
 }
 
 /* RFC 2463 */
 
-static void route_ipv6_unreachable(node_t *source, vpn_packet_t *packet, 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};
@@ -355,6 +417,9 @@ static void route_ipv6_unreachable(node_t *source, vpn_packet_t *packet, uint8_t
 	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;
@@ -374,7 +439,7 @@ static void route_ipv6_unreachable(node_t *source, vpn_packet_t *packet, uint8_t
 
 	/* Fill in ICMP header */
 	
-	icmp6.icmp6_type = ICMP6_DST_UNREACH;
+	icmp6.icmp6_type = type;
 	icmp6.icmp6_code = code;
 	icmp6.icmp6_cksum = 0;
 
@@ -401,9 +466,10 @@ static void route_ipv6_unreachable(node_t *source, vpn_packet_t *packet, uint8_t
 	send_packet(source, packet);
 }
 
-static void route_ipv6_unicast(node_t *source, vpn_packet_t *packet)
+static __inline__ void route_ipv6_unicast(node_t *source, vpn_packet_t *packet)
 {
 	subnet_t *subnet;
+	node_t *via;
 
 	cp();
 
@@ -421,7 +487,7 @@ static void route_ipv6_unicast(node_t *source, vpn_packet_t *packet)
 				ntohs(*(uint16_t *) &packet->data[50]),
 				ntohs(*(uint16_t *) &packet->data[52]));
 
-		route_ipv6_unreachable(source, packet, ICMP6_DST_UNREACH_ADDR);
+		route_ipv6_unreachable(source, packet, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_ADDR);
 		return;
 	}
 
@@ -431,37 +497,19 @@ static void route_ipv6_unicast(node_t *source, vpn_packet_t *packet)
 	}
 
 	if(!subnet->owner->status.reachable)
-		route_ipv6_unreachable(source, packet, ICMP6_DST_UNREACH_NOROUTE);
-	
-	send_packet(subnet->owner, packet);
-}
+		route_ipv6_unreachable(source, packet, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOROUTE);
 
-#ifdef ENABLE_MULTICAST
-static void route_ipv6_multicast(node_t *source, vpn_packet_t *packet)
-{
-	avl_node_t *node;
-	subnet_t *subnet, search = {0};
-
-	cp();
-
-	search.type = SUBNET_IPV6;
-	search.net.ipv6.address = *(ipv6_t *)(packet->data + ether_size + ip6_size + icmp6_size);
-	search.net.ipv6.prefixlength = 128;
-	search.owner = NULL;
-
-	ifdebug(TRAFFIC) logger(LOG_INFO, _("Multicasting packet of %d bytes from %s (%s)"), packet->len, source->name, source->hostname);
-
-	for(node = avl_search_closest_smaller_node(myself->subnet_tree, &search); node; node = node->next) {
-		subnet = node->data;
-		
-		if(subnet->type != SUBNET_IPV6 || memcmp(&subnet->net.ipv6.address, packet->data + ether_size + ip6_size + icmp6_size, sizeof(ipv6_t)))
-			break;
-		
-		if(subnet->owner != source)
-			send_packet(subnet->owner, packet);
+	via = (subnet->owner->via == myself) ? subnet->owner->nexthop : subnet->owner->via;
+	
+	if(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);
+		packet->len = via->mtu;
+		route_ipv6_unreachable(source, packet, ICMP6_PACKET_TOO_BIG, 0);
+		return;
 	}
+
+	send_packet(subnet->owner, packet);
 }
-#endif
 
 /* RFC 2461 */
 
@@ -591,101 +639,7 @@ static void route_neighborsol(node_t *source, vpn_packet_t *packet)
 	send_packet(source, packet);
 }
 
-/* RFC 2710 */
-
-#ifdef ENABLE_MULTICAST
-static void route_membershipreport(node_t *source, vpn_packet_t *packet)
-{
-	struct ip6_hdr ip6;
-	struct icmp6_hdr icmp6;
-	subnet_t *subnet, search = {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;
-
-	cp();
-
-	if(!checklength(source, packet, ether_size + ip6_size + icmp6_size + sizeof(ipv6_t)))
-		return;
-	
-	if(source != myself) {
-		ifdebug(TRAFFIC) logger(LOG_WARNING, _("Got membership report 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(&icmp6, packet->data + ether_size + ip6_size + 8, icmp6_size);
-
-	/* Create pseudo header */
-
-	pseudo.ip6_src = ip6.ip6_src;
-	pseudo.ip6_dst = ip6.ip6_dst;
-	pseudo.length = htonl(icmp6_size + sizeof(ipv6_t));
-	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 + 8 + icmp6_size, sizeof(ipv6_t), checksum);
-
-	if(checksum) {
-		ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: checksum error for membership report"));
-		return;
-	}
-
-	/* Check if the IPv6 address exists on the VPN */
-
-	search.type = SUBNET_IPV6;
-	search.net.ipv6.address = *(ipv6_t *)(packet->data + ether_size + ip6_size + 8 + icmp6_size);
-	search.net.ipv6.prefixlength = 128;
-	search.owner = myself;
-
-	subnet = avl_search(myself->subnet_tree, &search);
-
-	if(!subnet) {
-		avl_node_t *node;
-		connection_t *c;
-
-		ifdebug(TRAFFIC) logger(LOG_WARNING, _("Learned new IPv6 multicast address %hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx"),
-				ntohs(*(uint16_t *) &packet->data[70]),
-				ntohs(*(uint16_t *) &packet->data[72]),
-				ntohs(*(uint16_t *) &packet->data[74]),
-				ntohs(*(uint16_t *) &packet->data[76]),
-				ntohs(*(uint16_t *) &packet->data[78]),
-				ntohs(*(uint16_t *) &packet->data[80]),
-				ntohs(*(uint16_t *) &packet->data[82]),
-				ntohs(*(uint16_t *) &packet->data[84]));
-
-		subnet = new_subnet();
-		subnet->type = SUBNET_IPV6;
-		subnet->net.ipv6.address = *(ipv6_t *)(packet->data + ether_size + ip6_size + 8 + icmp6_size);
-		subnet->net.ipv6.prefixlength = 128;
-		subnet->expires = now + multicastexpire;
-		subnet_add(myself, subnet);
-
-		/* And tell all other tinc daemons it's ours */
-
-		for(node = connection_tree->head; node; node = node->next) {
-			c = node->data;
-			if(c->status.active)
-				send_add_subnet(c, subnet);
-		}
-	}
-
-	if(subnet->expires)
-		subnet->expires = now + multicastexpire;
-}
-#endif
-
-static void route_ipv6(node_t *source, vpn_packet_t *packet)
+static __inline__ void route_ipv6(node_t *source, vpn_packet_t *packet)
 {
 	cp();
 
@@ -697,20 +651,6 @@ static void route_ipv6(node_t *source, vpn_packet_t *packet)
 		return;
 	}
 
-#ifdef ENABLE_MULTICAST 
-	if(packet->data[20] == IPPROTO_HOPOPTS && checklength(source, packet, ether_size + ip6_size + 8)
-			&& packet->data[54] == IPPROTO_ICMPV6 && checklength(source, packet, ether_size + ip6_size + 8 + icmp6_size)
-			&& packet->data[62] == ICMP6_MEMBERSHIP_REPORT) {
-		route_membershipreport(source, packet);
-		return;
-	}
-	
-	if(packet->data[38] == 0xff && packet->data[39] & 0x0c) {
-		route_ipv6_multicast(source, packet);
-		return;
-	}
-#endif
-
 	route_ipv6_unicast(source, packet);
 }