X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fsubnet.c;h=d7b9f470bffe3d68c2e3c2383504d008a716badd;hp=48ac45e272a26e3884965cb3ce7d5cf54b8648f9;hb=fb5588856fa4dd6f140c72f7360302fe85b20c75;hpb=82e383710980534d38bb9a8ef22f20677cd85861

diff --git a/src/subnet.c b/src/subnet.c
index 48ac45e2..d7b9f470 100644
--- a/src/subnet.c
+++ b/src/subnet.c
@@ -1,7 +1,7 @@
 /*
     subnet.c -- handle subnet lookups and lists
-    Copyright (C) 2000,2001 Guus Sliepen <guus@sliepen.warande.net>,
-                  2000,2001 Ivo Timmermans <itimmermans@bigfoot.com>
+    Copyright (C) 2000-2010 Guus Sliepen <guus@tinc-vpn.org>,
+                  2000-2005 Ivo Timmermans
 
     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
@@ -13,345 +13,595 @@
     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: subnet.c,v 1.1.2.25 2001/10/27 12:13:17 guus Exp $
+    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 "config.h"
-
-#include <stdio.h>
-#include <syslog.h>
-#include <string.h>
+#include "system.h"
 
-#include "conf.h"
+#include "avl_tree.h"
+#include "device.h"
+#include "logger.h"
 #include "net.h"
+#include "netutl.h"
 #include "node.h"
+#include "process.h"
 #include "subnet.h"
-#include "system.h"
-
-#include <utils.h>
-#include <xalloc.h>
-#include <avl_tree.h>
+#include "utils.h"
+#include "xalloc.h"
 
 /* lists type of subnet */
 
 avl_tree_t *subnet_tree;
 
-void init_subnets(void)
-{
-cp
-  subnet_tree = avl_alloc_tree((avl_compare_t)subnet_compare, (avl_action_t)free_subnet);
-cp
+/* Subnet lookup cache */
+
+static ipv4_t cache_ipv4_address[2];
+static subnet_t *cache_ipv4_subnet[2];
+static bool cache_ipv4_valid[2];
+static int cache_ipv4_slot;
+
+static ipv6_t cache_ipv6_address[2];
+static subnet_t *cache_ipv6_subnet[2];
+static bool cache_ipv6_valid[2];
+static int cache_ipv6_slot;
+
+static mac_t cache_mac_address[2];
+static subnet_t *cache_mac_subnet[2];
+static bool cache_mac_valid[2];
+static int cache_mac_slot;
+
+void subnet_cache_flush(void) {
+	cache_ipv4_valid[0] = cache_ipv4_valid[1] = false;
+	cache_ipv6_valid[0] = cache_ipv6_valid[1] = false;
+	cache_mac_valid[0] = cache_mac_valid[1] = false;
 }
 
 /* Subnet comparison */
 
-int subnet_compare_mac(subnet_t *a, subnet_t *b)
-{
-  int result;
-cp
-  result = memcmp(&a->net.mac.address, &b->net.mac.address, sizeof(mac_t));
-  
-  if(result)
-    return result;
+static int subnet_compare_mac(const subnet_t *a, const subnet_t *b) {
+	int result;
+
+	result = memcmp(&a->net.mac.address, &b->net.mac.address, sizeof(mac_t));
+
+	if(result)
+		return result;
+	
+	result = a->weight - b->weight;
+
+	if(result || !a->owner || !b->owner)
+		return result;
 
-  return strcmp(a->owner->name, b->owner->name);
+	return strcmp(a->owner->name, b->owner->name);
 }
 
-int subnet_compare_ipv4(subnet_t *a, subnet_t *b)
-{
-cp
-  /* We compare as if a subnet is a number that equals (address << 32 + netmask). */
-   
-  if(a->net.ipv4.address < b->net.ipv4.address)
-    return -1;
-  else if(a->net.ipv4.address > b->net.ipv4.address)
-    return 1;
-
-  if(a->net.ipv4.mask < b->net.ipv4.mask)
-    return -1;
-  else if(a->net.ipv4.mask > b->net.ipv4.mask)
-    return 1;
-
-  return strcmp(a->owner->name, b->owner->name);
+static int subnet_compare_ipv4(const subnet_t *a, const subnet_t *b) {
+	int result;
+
+	result = b->net.ipv4.prefixlength - a->net.ipv4.prefixlength;
+
+	if(result)
+		return result;
+
+	result = memcmp(&a->net.ipv4.address, &b->net.ipv4.address, sizeof(ipv4_t));
+
+	if(result)
+		return result;
+	
+	result = a->weight - b->weight;
+
+	if(result || !a->owner || !b->owner)
+		return result;
+
+	return strcmp(a->owner->name, b->owner->name);
 }
 
-int subnet_compare_ipv6(subnet_t *a, subnet_t *b)
-{
-  int result;
-cp
-  /* Same as ipv4 case, but with nasty 128 bit addresses */
-  
-  result = memcmp(a->net.ipv6.address.x, b->net.ipv6.address.x, sizeof(ipv6_t));
-  
-  if(result)
-    return result;
-
-  result = memcmp(a->net.ipv6.mask.x, b->net.ipv6.mask.x, sizeof(ipv6_t));
-  
-  if(result)
-    return result;
-
-  return strcmp(a->owner->name, b->owner->name);
+static int subnet_compare_ipv6(const subnet_t *a, const subnet_t *b) {
+	int result;
+
+	result = b->net.ipv6.prefixlength - a->net.ipv6.prefixlength;
+
+	if(result)
+		return result;
+	
+	result = memcmp(&a->net.ipv6.address, &b->net.ipv6.address, sizeof(ipv6_t));
+
+	if(result)
+		return result;
+	
+	result = a->weight - b->weight;
+
+	if(result || !a->owner || !b->owner)
+		return result;
+
+	return strcmp(a->owner->name, b->owner->name);
 }
 
-int subnet_compare(subnet_t *a, subnet_t *b)
-{
-  int x;
-cp  
-  x = a->type - b->type;
-  if(x)
-    return x;
-    
-  switch(a->type)
-    {
-      case SUBNET_MAC:
-        return subnet_compare_mac(a, b);
-      case SUBNET_IPV4:
-        return subnet_compare_ipv4(a, b);
-      case SUBNET_IPV6:
-        return subnet_compare_ipv6(a, b);
-      default:
-        syslog(LOG_ERR, _("subnet_compare() was called with unknown subnet type %d, restarting!"), a->type);
-        sighup = 1;
-        return 0;
-    }
+int subnet_compare(const subnet_t *a, const subnet_t *b) {
+	int result;
+
+	result = a->type - b->type;
+
+	if(result)
+		return result;
+
+	switch (a->type) {
+	case SUBNET_MAC:
+		return subnet_compare_mac(a, b);
+	case SUBNET_IPV4:
+		return subnet_compare_ipv4(a, b);
+	case SUBNET_IPV6:
+		return subnet_compare_ipv6(a, b);
+	default:
+		logger(LOG_ERR, "subnet_compare() was called with unknown subnet type %d, exitting!",
+			   a->type);
+		exit(0);
+	}
+
+	return 0;
+}
+
+/* Initialising trees */
+
+void init_subnets(void) {
+	subnet_tree = avl_alloc_tree((avl_compare_t) subnet_compare, (avl_action_t) free_subnet);
+
+	subnet_cache_flush();
+}
+
+void exit_subnets(void) {
+	avl_delete_tree(subnet_tree);
+}
+
+avl_tree_t *new_subnet_tree(void) {
+	return avl_alloc_tree((avl_compare_t) subnet_compare, NULL);
+}
+
+void free_subnet_tree(avl_tree_t *subnet_tree) {
+	avl_delete_tree(subnet_tree);
 }
 
 /* Allocating and freeing space for subnets */
 
-subnet_t *new_subnet(void)
-{
-cp
-  return (subnet_t *)xmalloc(sizeof(subnet_t));
+subnet_t *new_subnet(void) {
+	return xmalloc_and_zero(sizeof(subnet_t));
 }
 
-void free_subnet(subnet_t *subnet)
-{
-cp
-  free(subnet);
+void free_subnet(subnet_t *subnet) {
+	free(subnet);
 }
 
-/* Linked list management */
+/* Adding and removing subnets */
+
+void subnet_add(node_t *n, subnet_t *subnet) {
+	subnet->owner = n;
 
-void subnet_add(node_t *n, subnet_t *subnet)
-{
-cp
-  subnet->owner = n;
+	avl_insert(subnet_tree, subnet);
+	avl_insert(n->subnet_tree, subnet);
 
-  avl_insert(subnet_tree, subnet);
-cp
-  avl_insert(n->subnet_tree, subnet);
-cp
+	subnet_cache_flush();
 }
 
-void subnet_del(node_t *n, subnet_t *subnet)
-{
-cp
-  avl_delete(n->subnet_tree, subnet);
-cp
-  avl_delete(subnet_tree, subnet);
-cp
+void subnet_del(node_t *n, subnet_t *subnet) {
+	avl_delete(n->subnet_tree, subnet);
+	avl_delete(subnet_tree, subnet);
+
+	subnet_cache_flush();
 }
 
 /* Ascii representation of subnets */
 
-subnet_t *str2net(char *subnetstr)
-{
-  int type;
-  subnet_t *subnet;
-cp
-  if(sscanf(subnetstr, "%d,", &type) != 1)
-    return NULL;
-cp
-  subnet = new_subnet();
-cp
-  switch(type)
-    {
-      case SUBNET_MAC:
-        if(sscanf(subnetstr, "%d,%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", &subnet->type,
-                   &subnet->net.mac.address.x[0],
-                   &subnet->net.mac.address.x[1],
-                   &subnet->net.mac.address.x[2],
-                   &subnet->net.mac.address.x[3],
-                   &subnet->net.mac.address.x[4],
-                   &subnet->net.mac.address.x[5]) != 7)
-          {
-            free_subnet(subnet);
-            return NULL;
-          }
-        break;
-      case SUBNET_IPV4:
-        if(sscanf(subnetstr, "%d,%lx/%lx", &subnet->type, &subnet->net.ipv4.address, &subnet->net.ipv4.mask) != 3)
-          {
-            free_subnet(subnet);
-            return NULL;
-          }
-        break;
-      case SUBNET_IPV6:
-        if(sscanf(subnetstr, "%d,%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx", &subnet->type,
-                   &subnet->net.ipv6.address.x[0],
-                   &subnet->net.ipv6.address.x[1],
-                   &subnet->net.ipv6.address.x[2],
-                   &subnet->net.ipv6.address.x[3],
-                   &subnet->net.ipv6.address.x[4],
-                   &subnet->net.ipv6.address.x[5],
-                   &subnet->net.ipv6.address.x[6],
-                   &subnet->net.ipv6.address.x[7],
-                   &subnet->net.ipv6.mask.x[0],
-                   &subnet->net.ipv6.mask.x[1],
-                   &subnet->net.ipv6.mask.x[2],
-                   &subnet->net.ipv6.mask.x[3],
-                   &subnet->net.ipv6.mask.x[4],
-                   &subnet->net.ipv6.mask.x[5],
-                   &subnet->net.ipv6.mask.x[6],
-                   &subnet->net.ipv6.mask.x[7]) != 17)
-          {
-            free_subnet(subnet);
-            return NULL;
-          }
-        break;
-      default:
-        free_subnet(subnet);
-        return NULL;
-    }
-cp
-  return subnet;
+bool str2net(subnet_t *subnet, const char *subnetstr) {
+	int i, l;
+	uint16_t x[8];
+	int weight = 10;
+
+	if(sscanf(subnetstr, "%hu.%hu.%hu.%hu/%d#%d",
+			  &x[0], &x[1], &x[2], &x[3], &l, &weight) >= 5) {
+		if(l < 0 || l > 32)
+			return false;
+
+		subnet->type = SUBNET_IPV4;
+		subnet->net.ipv4.prefixlength = l;
+		subnet->weight = weight;
+
+		for(i = 0; i < 4; i++) {
+			if(x[i] > 255)
+				return false;
+			subnet->net.ipv4.address.x[i] = x[i];
+		}
+
+		return true;
+	}
+
+	if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%d#%d",
+			  &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7],
+			  &l, &weight) >= 9) {
+		if(l < 0 || l > 128)
+			return false;
+
+		subnet->type = SUBNET_IPV6;
+		subnet->net.ipv6.prefixlength = l;
+		subnet->weight = weight;
+
+		for(i = 0; i < 8; i++)
+			subnet->net.ipv6.address.x[i] = htons(x[i]);
+
+		return true;
+	}
+
+	if(sscanf(subnetstr, "%hu.%hu.%hu.%hu#%d", &x[0], &x[1], &x[2], &x[3], &weight) >= 4) {
+		subnet->type = SUBNET_IPV4;
+		subnet->net.ipv4.prefixlength = 32;
+		subnet->weight = weight;
+
+		for(i = 0; i < 4; i++) {
+			if(x[i] > 255)
+				return false;
+			subnet->net.ipv4.address.x[i] = x[i];
+		}
+
+		return true;
+	}
+
+	if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx#%d",
+			  &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7], &weight) >= 8) {
+		subnet->type = SUBNET_IPV6;
+		subnet->net.ipv6.prefixlength = 128;
+		subnet->weight = weight;
+
+		for(i = 0; i < 8; i++)
+			subnet->net.ipv6.address.x[i] = htons(x[i]);
+
+		return true;
+	}
+
+	if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx#%d",
+			  &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &weight) >= 6) {
+		subnet->type = SUBNET_MAC;
+		subnet->weight = weight;
+
+		for(i = 0; i < 6; i++)
+			subnet->net.mac.address.x[i] = x[i];
+
+		return true;
+	}
+
+	// IPv6 short form
+	if(strstr(subnetstr, "::")) {
+		const char *p;
+		char *q;
+		int colons = 0;
+
+		// Count number of colons
+		for(p = subnetstr; *p; p++)
+			if(*p == ':')
+				colons++;
+
+		if(colons > 7)
+			return false;
+
+		// Scan numbers before the double colon
+		p = subnetstr;
+		for(i = 0; i < colons; i++) {
+			if(*p == ':')
+				break;
+			x[i] = strtoul(p, &q, 0x10);
+			if(!q || p == q || *q != ':')
+				return false;
+			p = ++q;
+		}
+
+		p++;
+		colons -= i;
+		if(!i) {
+			p++;
+			colons--;
+		}
+
+		if(!*p || *p == '/' || *p == '#')
+			colons--;
+
+		// Fill in the blanks
+		for(; i < 8 - colons; i++)
+			x[i] = 0;
+
+		// Scan the remaining numbers
+		for(; i < 8; i++) {
+			x[i] = strtoul(p, &q, 0x10);
+			if(!q || p == q)
+				return false;
+			if(i == 7) {
+				p = q;
+				break;
+			}
+			if(*q != ':')
+				return false;
+			p = ++q;
+		}
+
+		l = 128;
+		if(*p == '/')
+			sscanf(p, "/%d#%d", &l, &weight);
+		else if(*p == '#')
+			sscanf(p, "#%d", &weight);
+
+		if(l < 0 || l > 128)
+			return false;
+
+		subnet->type = SUBNET_IPV6;
+		subnet->net.ipv6.prefixlength = l;
+		subnet->weight = weight;
+
+		for(i = 0; i < 8; i++)
+			subnet->net.ipv6.address.x[i] = htons(x[i]);
+
+		return true;
+	}
+
+	return false;
 }
 
-char *net2str(subnet_t *subnet)
-{
-  char *netstr;
-cp
-  switch(subnet->type)
-    {
-      case SUBNET_MAC:
-        asprintf(&netstr, "%d,%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", subnet->type,
-                   subnet->net.mac.address.x[0],
-                   subnet->net.mac.address.x[1],
-                   subnet->net.mac.address.x[2],
-                   subnet->net.mac.address.x[3],
-                   subnet->net.mac.address.x[4],
-                   subnet->net.mac.address.x[5]);
-        break;
-      case SUBNET_IPV4:
-        asprintf(&netstr, "%d,%lx/%lx", subnet->type, subnet->net.ipv4.address, subnet->net.ipv4.mask);
-        break;
-      case SUBNET_IPV6:
-        asprintf(&netstr, "%d,%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx", subnet->type,
-                   subnet->net.ipv6.address.x[0],
-                   subnet->net.ipv6.address.x[1],
-                   subnet->net.ipv6.address.x[2],
-                   subnet->net.ipv6.address.x[3],
-                   subnet->net.ipv6.address.x[4],
-                   subnet->net.ipv6.address.x[5],
-                   subnet->net.ipv6.address.x[6],
-                   subnet->net.ipv6.address.x[7],
-                   subnet->net.ipv6.mask.x[0],
-                   subnet->net.ipv6.mask.x[1],
-                   subnet->net.ipv6.mask.x[2],
-                   subnet->net.ipv6.mask.x[3],
-                   subnet->net.ipv6.mask.x[4],
-                   subnet->net.ipv6.mask.x[5],
-                   subnet->net.ipv6.mask.x[6],
-                   subnet->net.ipv6.mask.x[7]);
-        break;
-      default:
-        asprintf(&netstr, _("unknown subnet type"));
-    }
-cp
-  return netstr;
+bool net2str(char *netstr, int len, const subnet_t *subnet) {
+	if(!netstr || !subnet) {
+		logger(LOG_ERR, "net2str() was called with netstr=%p, subnet=%p!", netstr, subnet);
+		return false;
+	}
+
+	switch (subnet->type) {
+		case SUBNET_MAC:
+			snprintf(netstr, len, "%hx:%hx:%hx:%hx:%hx:%hx#%d",
+					 subnet->net.mac.address.x[0],
+					 subnet->net.mac.address.x[1],
+					 subnet->net.mac.address.x[2],
+					 subnet->net.mac.address.x[3],
+					 subnet->net.mac.address.x[4],
+					 subnet->net.mac.address.x[5],
+					 subnet->weight);
+			break;
+
+		case SUBNET_IPV4:
+			snprintf(netstr, len, "%hu.%hu.%hu.%hu/%d#%d",
+					 subnet->net.ipv4.address.x[0],
+					 subnet->net.ipv4.address.x[1],
+					 subnet->net.ipv4.address.x[2],
+					 subnet->net.ipv4.address.x[3],
+					 subnet->net.ipv4.prefixlength,
+					 subnet->weight);
+			break;
+
+		case SUBNET_IPV6:
+			snprintf(netstr, len, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%d#%d",
+					 ntohs(subnet->net.ipv6.address.x[0]),
+					 ntohs(subnet->net.ipv6.address.x[1]),
+					 ntohs(subnet->net.ipv6.address.x[2]),
+					 ntohs(subnet->net.ipv6.address.x[3]),
+					 ntohs(subnet->net.ipv6.address.x[4]),
+					 ntohs(subnet->net.ipv6.address.x[5]),
+					 ntohs(subnet->net.ipv6.address.x[6]),
+					 ntohs(subnet->net.ipv6.address.x[7]),
+					 subnet->net.ipv6.prefixlength,
+					 subnet->weight);
+			break;
+
+		default:
+			logger(LOG_ERR,
+				   "net2str() was called with unknown subnet type %d, exiting!",
+				   subnet->type);
+			exit(0);
+	}
+
+	return true;
 }
 
 /* Subnet lookup routines */
 
-subnet_t *lookup_subnet(node_t *owner, subnet_t *subnet)
-{
-cp  
-  return avl_search(owner->subnet_tree, subnet);
+subnet_t *lookup_subnet(const node_t *owner, const subnet_t *subnet) {
+	return avl_search(owner->subnet_tree, subnet);
+}
+
+subnet_t *lookup_subnet_mac(const node_t *owner, const mac_t *address) {
+	subnet_t *p, *r = NULL;
+	avl_node_t *n;
+	int i;
+
+	// Check if this address is cached
+
+	for(i = 0; i < 2; i++) {
+		if(!cache_mac_valid[i])
+			continue;
+		if(owner && cache_mac_subnet[i] && cache_mac_subnet[i]->owner != owner)
+			continue;
+		if(!memcmp(address, &cache_mac_address[i], sizeof *address))
+			return cache_mac_subnet[i];
+	}
+
+	// Search all subnets for a matching one
+
+	for(n = owner ? owner->subnet_tree->head : subnet_tree->head; n; n = n->next) {
+		p = n->data;
+		
+		if(!p || p->type != SUBNET_MAC)
+			continue;
+
+		if(!memcmp(address, &p->net.mac.address, sizeof *address)) {
+			r = p;
+			if(p->owner->status.reachable)
+				break;
+		}
+	}
+
+	// Cache the result
+
+	cache_mac_slot = !cache_mac_slot;
+	memcpy(&cache_mac_address[cache_mac_slot], address, sizeof *address);
+	cache_mac_subnet[cache_mac_slot] = r;
+	cache_mac_valid[cache_mac_slot] = true;
+
+	return r;
 }
 
-subnet_t *lookup_subnet_mac(mac_t *address)
-{
-  subnet_t subnet, *p;
-cp
-  subnet.type = SUBNET_MAC;
-  memcpy(&subnet.net.mac.address, address, sizeof(mac_t));
+subnet_t *lookup_subnet_ipv4(const ipv4_t *address) {
+	subnet_t *p, *r = NULL;
+	avl_node_t *n;
+	int i;
+
+	// Check if this address is cached
+
+	for(i = 0; i < 2; i++) {
+		if(!cache_ipv4_valid[i])
+			continue;
+		if(!memcmp(address, &cache_ipv4_address[i], sizeof *address))
+			return cache_ipv4_subnet[i];
+	}
+
+	// Search all subnets for a matching one
+
+	for(n = subnet_tree->head; n; n = n->next) {
+		p = n->data;
+		
+		if(!p || p->type != SUBNET_IPV4)
+			continue;
 
-  p = (subnet_t *)avl_search(subnet_tree, &subnet);
-cp
-  return p;
+		if(!maskcmp(address, &p->net.ipv4.address, p->net.ipv4.prefixlength)) {
+			r = p;
+			if(p->owner->status.reachable)
+				break;
+		}
+	}
+
+	// Cache the result
+
+	cache_ipv4_slot = !cache_ipv4_slot;
+	memcpy(&cache_ipv4_address[cache_ipv4_slot], address, sizeof *address);
+	cache_ipv4_subnet[cache_ipv4_slot] = r;
+	cache_ipv4_valid[cache_ipv4_slot] = true;
+
+	return r;
 }
 
-subnet_t *lookup_subnet_ipv4(ipv4_t *address)
-{
-  subnet_t subnet, *p;
-cp
-  subnet.type = SUBNET_IPV4;
-  subnet.net.ipv4.address = *address;
-  subnet.net.ipv4.mask = 0xFFFFFFFF;
-
-  do
-  {
-    /* Go find subnet */
-  
-    p = (subnet_t *)avl_search_closest_smaller(subnet_tree, &subnet);
-
-  /* Check if the found subnet REALLY matches */
-cp
-    if(p)
-      {
-        if ((*address & p->net.ipv4.mask) == p->net.ipv4.address)
-          break;
-        else
-          {
-            /* Otherwise, see if there is a bigger enclosing subnet */
-
-            subnet.net.ipv4.mask = p->net.ipv4.mask << 1;
-            subnet.net.ipv4.address = p->net.ipv4.address & subnet.net.ipv4.mask;
-          }
-      }
-   } while (p);
-   
-   return p;
+subnet_t *lookup_subnet_ipv6(const ipv6_t *address) {
+	subnet_t *p, *r = NULL;
+	avl_node_t *n;
+	int i;
+
+	// Check if this address is cached
+
+	for(i = 0; i < 2; i++) {
+		if(!cache_ipv6_valid[i])
+			continue;
+		if(!memcmp(address, &cache_ipv6_address[i], sizeof *address))
+			return cache_ipv6_subnet[i];
+	}
+
+	// Search all subnets for a matching one
+
+	for(n = subnet_tree->head; n; n = n->next) {
+		p = n->data;
+		
+		if(!p || p->type != SUBNET_IPV6)
+			continue;
+
+		if(!maskcmp(address, &p->net.ipv6.address, p->net.ipv6.prefixlength)) {
+			r = p;
+			if(p->owner->status.reachable)
+				break;
+		}
+	}
+
+	// Cache the result
+
+	cache_ipv6_slot = !cache_ipv6_slot;
+	memcpy(&cache_ipv6_address[cache_ipv6_slot], address, sizeof *address);
+	cache_ipv6_subnet[cache_ipv6_slot] = r;
+	cache_ipv6_valid[cache_ipv6_slot] = true;
+
+	return r;
 }
 
-subnet_t *lookup_subnet_ipv6(ipv6_t *address)
-{
-  subnet_t subnet, *p;
-  int i;
-cp
-  subnet.type = SUBNET_IPV6;
-  memcpy(&subnet.net.ipv6.address, address, sizeof(ipv6_t));
-  memset(&subnet.net.ipv6.mask, 0xFF, 16);
-  
-  p = (subnet_t *)avl_search_closest_greater(subnet_tree, &subnet);
-  
-  if(p)
-    for(i=0; i<8; i++)
-      if((address->x[i] & p->net.ipv6.address.x[i]) != p->net.ipv6.address.x[i])
-        return NULL;
-
-  return p;
+void subnet_update(node_t *owner, subnet_t *subnet, bool up) {
+	avl_node_t *node;
+	int i;
+	char *envp[9] = {NULL};
+	char netstr[MAXNETSTR];
+	char *name, *address, *port;
+	char empty[] = "";
+
+	// Prepare environment variables to be passed to the script
+
+	xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
+	xasprintf(&envp[1], "DEVICE=%s", device ? : "");
+	xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
+	xasprintf(&envp[3], "NODE=%s", owner->name);
+
+	if(owner != myself) {
+		sockaddr2str(&owner->address, &address, &port);
+		// 4 and 5 are reserved for SUBNET and WEIGHT
+		xasprintf(&envp[6], "REMOTEADDRESS=%s", address);
+		xasprintf(&envp[7], "REMOTEPORT=%s", port);
+		free(port);
+		free(address);
+	}
+
+	name = up ? "subnet-up" : "subnet-down";
+
+	if(!subnet) {
+		for(node = owner->subnet_tree->head; node; node = node->next) {
+			subnet = node->data;
+			if(!net2str(netstr, sizeof netstr, subnet))
+				continue;
+			// Strip the weight from the subnet, and put it in its own environment variable
+			char *weight = strchr(netstr, '#');
+			if(weight)
+				*weight++ = 0;
+			else
+				weight = empty;
+
+			// Prepare the SUBNET and WEIGHT variables
+			if(envp[4])
+				free(envp[4]);
+			if(envp[5])
+				free(envp[5]);
+			xasprintf(&envp[4], "SUBNET=%s", netstr);
+			xasprintf(&envp[5], "WEIGHT=%s", weight);
+
+			execute_script(name, envp);
+		}
+	} else {
+		if(net2str(netstr, sizeof netstr, subnet)) {
+			// Strip the weight from the subnet, and put it in its own environment variable
+			char *weight = strchr(netstr, '#');
+			if(weight)
+				*weight++ = 0;
+			else
+				weight = empty;
+
+			// Prepare the SUBNET and WEIGHT variables
+			xasprintf(&envp[4], "SUBNET=%s", netstr);
+			xasprintf(&envp[5], "WEIGHT=%s", weight);
+
+			execute_script(name, envp);
+		}
+	}
+
+	for(i = 0; envp[i] && i < 9; i++)
+		free(envp[i]);
 }
 
-void dump_subnet_list(void)
-{
-  char *netstr;
-  subnet_t *subnet;
-  avl_node_t *node;
-cp
-  syslog(LOG_DEBUG, _("Subnet list:"));
-  for(node = subnet_tree->head; node; node = node->next)
-    {
-      subnet = (subnet_t *)node->data;
-      netstr = net2str(subnet);
-      syslog(LOG_DEBUG, " %s owner %s", netstr, subnet->owner->name);
-      free(netstr);
-    }
-  syslog(LOG_DEBUG, _("End of subnet list."));
-cp
+void dump_subnets(void) {
+	char netstr[MAXNETSTR];
+	subnet_t *subnet;
+	avl_node_t *node;
+
+	logger(LOG_DEBUG, "Subnet list:");
+
+	for(node = subnet_tree->head; node; node = node->next) {
+		subnet = node->data;
+		if(!net2str(netstr, sizeof netstr, subnet))
+			continue;
+		logger(LOG_DEBUG, " %s owner %s", netstr, subnet->owner->name);
+	}
+
+	logger(LOG_DEBUG, "End of subnet list.");
 }