Imported Upstream version 5.0.1

1 files changed, 1216 insertions, 496 deletions

diff --git a/src/libhydra/plugins/kernel_netlink/kernel_netlink_net.c b/src/libhydra/plugins/kernel_netlink/kernel_netlink_net.c
index cce0ff402..3f63a8496 100644
--- a/src/libhydra/plugins/kernel_netlink/kernel_netlink_net.c
+++ b/src/libhydra/plugins/kernel_netlink/kernel_netlink_net.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2008 Tobias Brunner
+ * Copyright (C) 2008-2012 Tobias Brunner
  * Copyright (C) 2005-2008 Martin Willi
  * Hochschule fuer Technik Rapperswil
  *
@@ -38,6 +38,7 @@
  */
 
 #include <sys/socket.h>
+#include <sys/utsname.h>
 #include <linux/netlink.h>
 #include <linux/rtnetlink.h>
 #include <unistd.h>
@@ -50,32 +51,38 @@
 #include <hydra.h>
 #include <debug.h>
 #include <threading/thread.h>
-#include <threading/condvar.h>
 #include <threading/mutex.h>
+#include <threading/rwlock.h>
+#include <threading/rwlock_condvar.h>
+#include <threading/spinlock.h>
+#include <utils/hashtable.h>
 #include <utils/linked_list.h>
 #include <processing/jobs/callback_job.h>
 
 /** delay before firing roam events (ms) */
 #define ROAM_DELAY 100
 
+/** delay before reinstalling routes (ms) */
+#define ROUTE_DELAY 100
+
 typedef struct addr_entry_t addr_entry_t;
 
 /**
- * IP address in an inface_entry_t
+ * IP address in an iface_entry_t
  */
 struct addr_entry_t {
 
-	/** The ip address */
+	/** the ip address */
 	host_t *ip;
 
-	/** virtual IP managed by us */
-	bool virtual;
-
 	/** scope of the address */
 	u_char scope;
 
-	/** Number of times this IP is used, if virtual */
+	/** number of times this IP is used, if virtual (i.e. managed by us) */
 	u_int refcount;
+
+	/** TRUE once it is installed, if virtual */
+	bool installed;
 };
 
 /**
@@ -105,6 +112,9 @@ struct iface_entry_t {
 
 	/** list of addresses as host_t */
 	linked_list_t *addrs;
+
+	/** TRUE if usable by config */
+	bool usable;
 };
 
 /**
@@ -116,6 +126,208 @@ static void iface_entry_destroy(iface_entry_t *this)
 	free(this);
 }
 
+/**
+ * find an interface entry by index
+ */
+static bool iface_entry_by_index(iface_entry_t *this, int *ifindex)
+{
+	return this->ifindex == *ifindex;
+}
+
+/**
+ * find an interface entry by name
+ */
+static bool iface_entry_by_name(iface_entry_t *this, char *ifname)
+{
+	return streq(this->ifname, ifname);
+}
+
+/**
+ * check if an interface is up
+ */
+static inline bool iface_entry_up(iface_entry_t *iface)
+{
+	return (iface->flags & IFF_UP) == IFF_UP;
+}
+
+/**
+ * check if an interface is up and usable
+ */
+static inline bool iface_entry_up_and_usable(iface_entry_t *iface)
+{
+	return iface->usable && iface_entry_up(iface);
+}
+
+typedef struct addr_map_entry_t addr_map_entry_t;
+
+/**
+ * Entry that maps an IP address to an interface entry
+ */
+struct addr_map_entry_t {
+	/** The IP address */
+	host_t *ip;
+
+	/** The address entry for this IP address */
+	addr_entry_t *addr;
+
+	/** The interface this address is installed on */
+	iface_entry_t *iface;
+};
+
+/**
+ * Hash a addr_map_entry_t object, all entries with the same IP address
+ * are stored in the same bucket
+ */
+static u_int addr_map_entry_hash(addr_map_entry_t *this)
+{
+	return chunk_hash(this->ip->get_address(this->ip));
+}
+
+/**
+ * Compare two addr_map_entry_t objects, two entries are equal if they are
+ * installed on the same interface
+ */
+static bool addr_map_entry_equals(addr_map_entry_t *a, addr_map_entry_t *b)
+{
+	return a->iface->ifindex == b->iface->ifindex &&
+		   a->ip->ip_equals(a->ip, b->ip);
+}
+
+/**
+ * Used with get_match this finds an address entry if it is installed on
+ * an up and usable interface
+ */
+static bool addr_map_entry_match_up_and_usable(addr_map_entry_t *a,
+											   addr_map_entry_t *b)
+{
+	return iface_entry_up_and_usable(b->iface) &&
+		   a->ip->ip_equals(a->ip, b->ip);
+}
+
+/**
+ * Used with get_match this finds an address entry if it is installed on
+ * any active local interface
+ */
+static bool addr_map_entry_match_up(addr_map_entry_t *a, addr_map_entry_t *b)
+{
+	return iface_entry_up(b->iface) && a->ip->ip_equals(a->ip, b->ip);
+}
+
+/**
+ * Used with get_match this finds an address entry if it is installed on
+ * any local interface
+ */
+static bool addr_map_entry_match(addr_map_entry_t *a, addr_map_entry_t *b)
+{
+	return a->ip->ip_equals(a->ip, b->ip);
+}
+
+typedef struct route_entry_t route_entry_t;
+
+/**
+ * Installed routing entry
+ */
+struct route_entry_t {
+	/** Name of the interface the route is bound to */
+	char *if_name;
+
+	/** Source ip of the route */
+	host_t *src_ip;
+
+	/** Gateway for this route */
+	host_t *gateway;
+
+	/** Destination net */
+	chunk_t dst_net;
+
+	/** Destination net prefixlen */
+	u_int8_t prefixlen;
+};
+
+/**
+ * Clone a route_entry_t object.
+ */
+static route_entry_t *route_entry_clone(route_entry_t *this)
+{
+	route_entry_t *route;
+
+	INIT(route,
+		.if_name = strdup(this->if_name),
+		.src_ip = this->src_ip->clone(this->src_ip),
+		.gateway = this->gateway->clone(this->gateway),
+		.dst_net = chunk_clone(this->dst_net),
+		.prefixlen = this->prefixlen,
+	);
+	return route;
+}
+
+/**
+ * Destroy a route_entry_t object
+ */
+static void route_entry_destroy(route_entry_t *this)
+{
+	free(this->if_name);
+	DESTROY_IF(this->src_ip);
+	DESTROY_IF(this->gateway);
+	chunk_free(&this->dst_net);
+	free(this);
+}
+
+/**
+ * Hash a route_entry_t object
+ */
+static u_int route_entry_hash(route_entry_t *this)
+{
+	return chunk_hash_inc(chunk_from_thing(this->prefixlen),
+						  chunk_hash(this->dst_net));
+}
+
+/**
+ * Compare two route_entry_t objects
+ */
+static bool route_entry_equals(route_entry_t *a, route_entry_t *b)
+{
+	return a->if_name && b->if_name && streq(a->if_name, b->if_name) &&
+		   a->src_ip->ip_equals(a->src_ip, b->src_ip) &&
+		   a->gateway->ip_equals(a->gateway, b->gateway) &&
+		   chunk_equals(a->dst_net, b->dst_net) && a->prefixlen == b->prefixlen;
+}
+
+typedef struct net_change_t net_change_t;
+
+/**
+ * Queued network changes
+ */
+struct net_change_t {
+	/** Name of the interface that got activated (or an IP appeared on) */
+	char *if_name;
+};
+
+/**
+ * Destroy a net_change_t object
+ */
+static void net_change_destroy(net_change_t *this)
+{
+	free(this->if_name);
+	free(this);
+}
+
+/**
+ * Hash a net_change_t object
+ */
+static u_int net_change_hash(net_change_t *this)
+{
+	return chunk_hash(chunk_create(this->if_name, strlen(this->if_name)));
+}
+
+/**
+ * Compare two net_change_t objects
+ */
+static bool net_change_equals(net_change_t *a, net_change_t *b)
+{
+	return streq(a->if_name, b->if_name);
+}
+
 typedef struct private_kernel_netlink_net_t private_kernel_netlink_net_t;
 
 /**
@@ -128,14 +340,14 @@ struct private_kernel_netlink_net_t {
 	kernel_netlink_net_t public;
 
 	/**
-	 * mutex to lock access to various lists
+	 * lock to access various lists and maps
 	 */
-	mutex_t *mutex;
+	rwlock_t *lock;
 
 	/**
 	 * condition variable to signal virtual IP add/removal
 	 */
-	condvar_t *condvar;
+	rwlock_condvar_t *condvar;
 
 	/**
 	 * Cached list of interfaces and its addresses (iface_entry_t)
@@ -143,9 +355,14 @@ struct private_kernel_netlink_net_t {
 	linked_list_t *ifaces;
 
 	/**
-	 * job receiving netlink events
+	 * Map for IP addresses to iface_entry_t objects (addr_map_entry_t)
 	 */
-	callback_job_t *job;
+	hashtable_t *addrs;
+
+	/**
+	 * Map for virtual IP addresses to iface_entry_t objects (addr_map_entry_t)
+	 */
+	hashtable_t *vips;
 
 	/**
 	 * netlink rt socket (routing)
@@ -158,9 +375,14 @@ struct private_kernel_netlink_net_t {
 	int socket_events;
 
 	/**
-	 * time of the last roam event
+	 * earliest time of the next roam event
+	 */
+	timeval_t next_roam;
+
+	/**
+	 * lock to check and update roam event time
 	 */
-	timeval_t last_roam;
+	spinlock_t *roam_lock;
 
 	/**
 	 * routing table to install routes
@@ -173,6 +395,31 @@ struct private_kernel_netlink_net_t {
 	int routing_table_prio;
 
 	/**
+	 * installed routes
+	 */
+	hashtable_t *routes;
+
+	/**
+	 * mutex for routes
+	 */
+	mutex_t *routes_lock;
+
+	/**
+	 * interface changes which may trigger route reinstallation
+	 */
+	hashtable_t *net_changes;
+
+	/**
+	 * mutex for route reinstallation triggers
+	 */
+	mutex_t *net_changes_lock;
+
+	/**
+	 * time of last route reinstallation
+	 */
+	timeval_t last_route_reinstall;
+
+	/**
 	 * whether to react to RTM_NEWROUTE or RTM_DELROUTE events
 	 */
 	bool process_route;
@@ -183,79 +430,253 @@ struct private_kernel_netlink_net_t {
 	bool install_virtual_ip;
 
 	/**
+	 * the name of the interface virtual IP addresses are installed on
+	 */
+	char *install_virtual_ip_on;
+
+	/**
+	 * whether preferred source addresses can be specified for IPv6 routes
+	 */
+	bool rta_prefsrc_for_ipv6;
+
+	/**
 	 * list with routing tables to be excluded from route lookup
 	 */
 	linked_list_t *rt_exclude;
 };
 
 /**
- * get the refcount of a virtual ip
+ * Forward declaration
+ */
+static status_t manage_srcroute(private_kernel_netlink_net_t *this,
+								int nlmsg_type, int flags, chunk_t dst_net,
+								u_int8_t prefixlen, host_t *gateway,
+								host_t *src_ip, char *if_name);
+
+/**
+ * Clear the queued network changes.
  */
-static int get_vip_refcount(private_kernel_netlink_net_t *this, host_t* ip)
+static void net_changes_clear(private_kernel_netlink_net_t *this)
 {
-	enumerator_t *ifaces, *addrs;
-	iface_entry_t *iface;
-	addr_entry_t *addr;
-	int refcount = 0;
+	enumerator_t *enumerator;
+	net_change_t *change;
 
-	ifaces = this->ifaces->create_enumerator(this->ifaces);
-	while (ifaces->enumerate(ifaces, (void**)&iface))
+	enumerator = this->net_changes->create_enumerator(this->net_changes);
+	while (enumerator->enumerate(enumerator, NULL, (void**)&change))
 	{
-		addrs = iface->addrs->create_enumerator(iface->addrs);
-		while (addrs->enumerate(addrs, (void**)&addr))
-		{
-			if (addr->virtual && (iface->flags & IFF_UP) &&
-				ip->ip_equals(ip, addr->ip))
+		this->net_changes->remove_at(this->net_changes, enumerator);
+		net_change_destroy(change);
+	}
+	enumerator->destroy(enumerator);
+}
+
+/**
+ * Act upon queued network changes.
+ */
+static job_requeue_t reinstall_routes(private_kernel_netlink_net_t *this)
+{
+	enumerator_t *enumerator;
+	route_entry_t *route;
+
+	this->net_changes_lock->lock(this->net_changes_lock);
+	this->routes_lock->lock(this->routes_lock);
+
+	enumerator = this->routes->create_enumerator(this->routes);
+	while (enumerator->enumerate(enumerator, NULL, (void**)&route))
+	{
+		net_change_t *change, lookup = {
+			.if_name = route->if_name,
+		};
+		/* check if a change for the outgoing interface is queued */
+		change = this->net_changes->get(this->net_changes, &lookup);
+		if (!change)
+		{	/* in case src_ip is not on the outgoing interface */
+			if (this->public.interface.get_interface(&this->public.interface,
+												route->src_ip, &lookup.if_name))
 			{
-				refcount = addr->refcount;
-				break;
+				if (!streq(lookup.if_name, route->if_name))
+				{
+					change = this->net_changes->get(this->net_changes, &lookup);
+				}
+				free(lookup.if_name);
 			}
 		}
-		addrs->destroy(addrs);
-		if (refcount)
+		if (change)
 		{
-			break;
+			manage_srcroute(this, RTM_NEWROUTE, NLM_F_CREATE | NLM_F_EXCL,
+							route->dst_net, route->prefixlen, route->gateway,
+							route->src_ip, route->if_name);
 		}
 	}
-	ifaces->destroy(ifaces);
+	enumerator->destroy(enumerator);
+	this->routes_lock->unlock(this->routes_lock);
+
+	net_changes_clear(this);
+	this->net_changes_lock->unlock(this->net_changes_lock);
+	return JOB_REQUEUE_NONE;
+}
+
+/**
+ * Queue route reinstallation caused by network changes for a given interface.
+ *
+ * The route reinstallation is delayed for a while and only done once for
+ * several calls during this delay, in order to avoid doing it too often.
+ * The interface name is freed.
+ */
+static void queue_route_reinstall(private_kernel_netlink_net_t *this,
+								  char *if_name)
+{
+	net_change_t *update, *found;
+	timeval_t now;
+	job_t *job;
+
+	INIT(update,
+		.if_name = if_name
+	);
+
+	this->net_changes_lock->lock(this->net_changes_lock);
+	found = this->net_changes->put(this->net_changes, update, update);
+	if (found)
+	{
+		net_change_destroy(found);
+	}
+	time_monotonic(&now);
+	if (timercmp(&now, &this->last_route_reinstall, >))
+	{
+		now.tv_usec += ROUTE_DELAY * 1000;
+		while (now.tv_usec > 1000000)
+		{
+			now.tv_sec++;
+			now.tv_usec -= 1000000;
+		}
+		this->last_route_reinstall = now;
+
+		job = (job_t*)callback_job_create((callback_job_cb_t)reinstall_routes,
+										  this, NULL, NULL);
+		lib->scheduler->schedule_job_ms(lib->scheduler, job, ROUTE_DELAY);
+	}
+	this->net_changes_lock->unlock(this->net_changes_lock);
+}
 
-	return refcount;
+/**
+ * check if the given IP is known as virtual IP and currently installed
+ *
+ * this function will also return TRUE if the virtual IP entry disappeared.
+ * in that case the returned entry will be NULL.
+ *
+ * this->lock must be held when calling this function
+ */
+static bool is_vip_installed_or_gone(private_kernel_netlink_net_t *this,
+									 host_t *ip, addr_map_entry_t **entry)
+{
+	addr_map_entry_t lookup = {
+		.ip = ip,
+	};
+
+	*entry = this->vips->get_match(this->vips, &lookup,
+								  (void*)addr_map_entry_match);
+	if (*entry == NULL)
+	{	/* the virtual IP disappeared */
+		return TRUE;
+	}
+	return (*entry)->addr->installed;
+}
+
+/**
+ * check if the given IP is known as virtual IP
+ *
+ * this->lock must be held when calling this function
+ */
+static bool is_known_vip(private_kernel_netlink_net_t *this, host_t *ip)
+{
+	addr_map_entry_t lookup = {
+		.ip = ip,
+	};
+
+	return this->vips->get_match(this->vips, &lookup,
+								(void*)addr_map_entry_match) != NULL;
+}
+
+/**
+ * Add an address map entry
+ */
+static void addr_map_entry_add(hashtable_t *map, addr_entry_t *addr,
+							   iface_entry_t *iface)
+{
+	addr_map_entry_t *entry;
+
+	INIT(entry,
+		.ip = addr->ip,
+		.addr = addr,
+		.iface = iface,
+	);
+	entry = map->put(map, entry, entry);
+	free(entry);
+}
+
+/**
+ * Remove an address map entry
+ */
+static void addr_map_entry_remove(hashtable_t *map, addr_entry_t *addr,
+								  iface_entry_t *iface)
+{
+	addr_map_entry_t *entry, lookup = {
+		.ip = addr->ip,
+		.addr = addr,
+		.iface = iface,
+	};
+
+	entry = map->remove(map, &lookup);
+	free(entry);
 }
 
 /**
  * get the first non-virtual ip address on the given interface.
+ * if a candidate address is given, we first search for that address and if not
+ * found return the address as above.
  * returned host is a clone, has to be freed by caller.
+ *
+ * this->lock must be held when calling this function
  */
 static host_t *get_interface_address(private_kernel_netlink_net_t *this,
-									 int ifindex, int family)
+									 int ifindex, int family, host_t *candidate)
 {
-	enumerator_t *ifaces, *addrs;
 	iface_entry_t *iface;
+	enumerator_t *addrs;
 	addr_entry_t *addr;
 	host_t *ip = NULL;
 
-	this->mutex->lock(this->mutex);
-	ifaces = this->ifaces->create_enumerator(this->ifaces);
-	while (ifaces->enumerate(ifaces, &iface))
+	if (this->ifaces->find_first(this->ifaces, (void*)iface_entry_by_index,
+								 (void**)&iface, &ifindex) == SUCCESS)
 	{
-		if (iface->ifindex == ifindex)
-		{
+		if (iface->usable)
+		{	/* only use interfaces not excluded by config */
 			addrs = iface->addrs->create_enumerator(iface->addrs);
 			while (addrs->enumerate(addrs, &addr))
 			{
-				if (!addr->virtual && addr->ip->get_family(addr->ip) == family)
+				if (addr->refcount)
+				{	/* ignore virtual IP addresses */
+					continue;
+				}
+				if (addr->ip->get_family(addr->ip) == family)
 				{
-					ip = addr->ip->clone(addr->ip);
-					break;
+					if (!candidate || candidate->ip_equals(candidate, addr->ip))
+					{	/* stop at the first address if we don't search for a
+						 * candidate or if the candidate matches */
+						ip = addr->ip;
+						break;
+					}
+					else if (!ip)
+					{	/* store the first address as fallback if candidate is
+						 * not found */
+						ip = addr->ip;
+					}
 				}
 			}
 			addrs->destroy(addrs);
-			break;
 		}
 	}
-	ifaces->destroy(ifaces);
-	this->mutex->unlock(this->mutex);
-	return ip;
+	return ip ? ip->clone(ip) : NULL;
 }
 
 /**
@@ -277,21 +698,60 @@ static void fire_roam_event(private_kernel_netlink_net_t *this, bool address)
 	job_t *job;
 
 	time_monotonic(&now);
-	if (timercmp(&now, &this->last_roam, >))
+	this->roam_lock->lock(this->roam_lock);
+	if (!timercmp(&now, &this->next_roam, >))
 	{
-		now.tv_usec += ROAM_DELAY * 1000;
-		while (now.tv_usec > 1000000)
-		{
-			now.tv_sec++;
-			now.tv_usec -= 1000000;
-		}
-		this->last_roam = now;
+		this->roam_lock->unlock(this->roam_lock);
+		return;
+	}
+	now.tv_usec += ROAM_DELAY * 1000;
+	while (now.tv_usec > 1000000)
+	{
+		now.tv_sec++;
+		now.tv_usec -= 1000000;
+	}
+	this->next_roam = now;
+	this->roam_lock->unlock(this->roam_lock);
+
+	job = (job_t*)callback_job_create((callback_job_cb_t)roam_event,
+									  (void*)(uintptr_t)(address ? 1 : 0),
+									   NULL, NULL);
+	lib->scheduler->schedule_job_ms(lib->scheduler, job, ROAM_DELAY);
+}
 
-		job = (job_t*)callback_job_create((callback_job_cb_t)roam_event,
-										  (void*)(uintptr_t)(address ? 1 : 0),
-										  NULL, NULL);
-		lib->scheduler->schedule_job_ms(lib->scheduler, job, ROAM_DELAY);
+/**
+ * check if an interface with a given index is up and usable
+ *
+ * this->lock must be locked when calling this function
+ */
+static bool is_interface_up_and_usable(private_kernel_netlink_net_t *this,
+									   int index)
+{
+	iface_entry_t *iface;
+
+	if (this->ifaces->find_first(this->ifaces, (void*)iface_entry_by_index,
+								 (void**)&iface, &index) == SUCCESS)
+	{
+		return iface_entry_up_and_usable(iface);
+	}
+	return FALSE;
+}
+
+/**
+ * unregister the current addr_entry_t from the hashtable it is stored in
+ *
+ * this->lock must be locked when calling this function
+ */
+static void addr_entry_unregister(addr_entry_t *addr, iface_entry_t *iface,
+								  private_kernel_netlink_net_t *this)
+{
+	if (addr->refcount)
+	{
+		addr_map_entry_remove(this->vips, addr, iface);
+		this->condvar->broadcast(this->condvar);
+		return;
 	}
+	addr_map_entry_remove(this->addrs, addr, iface);
 }
 
 /**
@@ -306,9 +766,9 @@ static void process_link(private_kernel_netlink_net_t *this,
 	enumerator_t *enumerator;
 	iface_entry_t *current, *entry = NULL;
 	char *name = NULL;
-	bool update = FALSE;
+	bool update = FALSE, update_routes = FALSE;
 
-	while(RTA_OK(rta, rtasize))
+	while (RTA_OK(rta, rtasize))
 	{
 		switch (rta->rta_type)
 		{
@@ -323,40 +783,30 @@ static void process_link(private_kernel_netlink_net_t *this,
 		name = "(unknown)";
 	}
 
-	this->mutex->lock(this->mutex);
+	this->lock->write_lock(this->lock);
 	switch (hdr->nlmsg_type)
 	{
 		case RTM_NEWLINK:
 		{
-			if (msg->ifi_flags & IFF_LOOPBACK)
-			{	/* ignore loopback interfaces */
-				break;
-			}
-			enumerator = this->ifaces->create_enumerator(this->ifaces);
-			while (enumerator->enumerate(enumerator, &current))
-			{
-				if (current->ifindex == msg->ifi_index)
-				{
-					entry = current;
-					break;
-				}
-			}
-			enumerator->destroy(enumerator);
-			if (!entry)
+			if (this->ifaces->find_first(this->ifaces,
+									(void*)iface_entry_by_index, (void**)&entry,
+									&msg->ifi_index) != SUCCESS)
 			{
-				entry = malloc_thing(iface_entry_t);
-				entry->ifindex = msg->ifi_index;
-				entry->flags = 0;
-				entry->addrs = linked_list_create();
+				INIT(entry,
+					.ifindex = msg->ifi_index,
+					.addrs = linked_list_create(),
+					.usable = hydra->kernel_interface->is_interface_usable(
+												hydra->kernel_interface, name),
+				);
 				this->ifaces->insert_last(this->ifaces, entry);
 			}
 			strncpy(entry->ifname, name, IFNAMSIZ);
 			entry->ifname[IFNAMSIZ-1] = '\0';
-			if (event)
+			if (event && entry->usable)
 			{
 				if (!(entry->flags & IFF_UP) && (msg->ifi_flags & IFF_UP))
 				{
-					update = TRUE;
+					update = update_routes = TRUE;
 					DBG1(DBG_KNL, "interface %s activated", name);
 				}
 				if ((entry->flags & IFF_UP) && !(msg->ifi_flags & IFF_UP))
@@ -375,12 +825,16 @@ static void process_link(private_kernel_netlink_net_t *this,
 			{
 				if (current->ifindex == msg->ifi_index)
 				{
-					if (event)
+					if (event && current->usable)
 					{
 						update = TRUE;
 						DBG1(DBG_KNL, "interface %s deleted", current->ifname);
 					}
+					/* TODO: move virtual IPs installed on this interface to
+					 * another interface? */
 					this->ifaces->remove_at(this->ifaces, enumerator);
+					current->addrs->invoke_function(current->addrs,
+								(void*)addr_entry_unregister, current, this);
 					iface_entry_destroy(current);
 					break;
 				}
@@ -389,9 +843,13 @@ static void process_link(private_kernel_netlink_net_t *this,
 			break;
 		}
 	}
-	this->mutex->unlock(this->mutex);
+	this->lock->unlock(this->lock);
+
+	if (update_routes && event)
+	{
+		queue_route_reinstall(this, strdup(name));
+	}
 
-	/* send an update to all IKE_SAs */
 	if (update && event)
 	{
 		fire_roam_event(this, TRUE);
@@ -408,13 +866,12 @@ static void process_addr(private_kernel_netlink_net_t *this,
 	struct rtattr *rta = IFA_RTA(msg);
 	size_t rtasize = IFA_PAYLOAD (hdr);
 	host_t *host = NULL;
-	enumerator_t *ifaces, *addrs;
 	iface_entry_t *iface;
-	addr_entry_t *addr;
 	chunk_t local = chunk_empty, address = chunk_empty;
+	char *route_ifname = NULL;
 	bool update = FALSE, found = FALSE, changed = FALSE;
 
-	while(RTA_OK(rta, rtasize))
+	while (RTA_OK(rta, rtasize))
 	{
 		switch (rta->rta_type)
 		{
@@ -447,65 +904,92 @@ static void process_addr(private_kernel_netlink_net_t *this,
 		return;
 	}
 
-	this->mutex->lock(this->mutex);
-	ifaces = this->ifaces->create_enumerator(this->ifaces);
-	while (ifaces->enumerate(ifaces, &iface))
+	this->lock->write_lock(this->lock);
+	if (this->ifaces->find_first(this->ifaces, (void*)iface_entry_by_index,
+								 (void**)&iface, &msg->ifa_index) == SUCCESS)
 	{
-		if (iface->ifindex == msg->ifa_index)
+		addr_map_entry_t *entry, lookup = {
+			.ip = host,
+			.iface = iface,
+		};
+		addr_entry_t *addr;
+
+		entry = this->vips->get(this->vips, &lookup);
+		if (entry)
 		{
-			addrs = iface->addrs->create_enumerator(iface->addrs);
-			while (addrs->enumerate(addrs, &addr))
+			if (hdr->nlmsg_type == RTM_NEWADDR)
+			{	/* mark as installed and signal waiting threads */
+				entry->addr->installed = TRUE;
+			}
+			else
+			{	/* the address was already marked as uninstalled */
+				addr = entry->addr;
+				iface->addrs->remove(iface->addrs, addr, NULL);
+				addr_map_entry_remove(this->vips, addr, iface);
+				addr_entry_destroy(addr);
+			}
+			/* no roam events etc. for virtual IPs */
+			this->condvar->broadcast(this->condvar);
+			this->lock->unlock(this->lock);
+			host->destroy(host);
+			return;
+		}
+		entry = this->addrs->get(this->addrs, &lookup);
+		if (entry)
+		{
+			if (hdr->nlmsg_type == RTM_DELADDR)
 			{
-				if (host->ip_equals(host, addr->ip))
+				found = TRUE;
+				addr = entry->addr;
+				iface->addrs->remove(iface->addrs, addr, NULL);
+				if (iface->usable)
 				{
-					found = TRUE;
-					if (hdr->nlmsg_type == RTM_DELADDR)
-					{
-						iface->addrs->remove_at(iface->addrs, addrs);
-						if (!addr->virtual)
-						{
-							changed = TRUE;
-							DBG1(DBG_KNL, "%H disappeared from %s",
-								 host, iface->ifname);
-						}
-						addr_entry_destroy(addr);
-					}
-					else if (hdr->nlmsg_type == RTM_NEWADDR && addr->virtual)
-					{
-						addr->refcount = 1;
-					}
+					changed = TRUE;
+					DBG1(DBG_KNL, "%H disappeared from %s", host,
+						 iface->ifname);
 				}
+				addr_map_entry_remove(this->addrs, addr, iface);
+				addr_entry_destroy(addr);
 			}
-			addrs->destroy(addrs);
-
+		}
+		else
+		{
 			if (hdr->nlmsg_type == RTM_NEWADDR)
 			{
-				if (!found)
+				found = TRUE;
+				changed = TRUE;
+				route_ifname = strdup(iface->ifname);
+				INIT(addr,
+					.ip = host->clone(host),
+					.scope = msg->ifa_scope,
+				);
+				iface->addrs->insert_last(iface->addrs, addr);
+				addr_map_entry_add(this->addrs, addr, iface);
+				if (event && iface->usable)
 				{
-					found = TRUE;
-					changed = TRUE;
-					addr = malloc_thing(addr_entry_t);
-					addr->ip = host->clone(host);
-					addr->virtual = FALSE;
-					addr->refcount = 1;
-					addr->scope = msg->ifa_scope;
-
-					iface->addrs->insert_last(iface->addrs, addr);
-					if (event)
-					{
-						DBG1(DBG_KNL, "%H appeared on %s", host, iface->ifname);
-					}
+					DBG1(DBG_KNL, "%H appeared on %s", host, iface->ifname);
 				}
 			}
-			if (found && (iface->flags & IFF_UP))
-			{
-				update = TRUE;
-			}
-			break;
+		}
+		if (found && (iface->flags & IFF_UP))
+		{
+			update = TRUE;
+		}
+		if (!iface->usable)
+		{	/* ignore events for interfaces excluded by config */
+			update = changed = FALSE;
 		}
 	}
-	ifaces->destroy(ifaces);
-	this->mutex->unlock(this->mutex);
+	this->lock->unlock(this->lock);
+
+	if (update && event && route_ifname)
+	{
+		queue_route_reinstall(this, route_ifname);
+	}
+	else
+	{
+		free(route_ifname);
+	}
 	host->destroy(host);
 
 	/* send an update to all IKE_SAs */
@@ -532,6 +1016,10 @@ static void process_route(private_kernel_netlink_net_t *this, struct nlmsghdr *h
 	{
 		return;
 	}
+	else if (msg->rtm_flags & RTM_F_CLONED)
+	{	/* ignore cached routes, seem to be created a lot for IPv6 */
+		return;
+	}
 
 	while (RTA_OK(rta, rtasize))
 	{
@@ -551,20 +1039,26 @@ static void process_route(private_kernel_netlink_net_t *this, struct nlmsghdr *h
 		}
 		rta = RTA_NEXT(rta, rtasize);
 	}
+	this->lock->read_lock(this->lock);
+	if (rta_oif && !is_interface_up_and_usable(this, rta_oif))
+	{	/* ignore route changes for interfaces that are ignored or down */
+		this->lock->unlock(this->lock);
+		DESTROY_IF(host);
+		return;
+	}
 	if (!host && rta_oif)
 	{
-		host = get_interface_address(this, rta_oif, msg->rtm_family);
+		host = get_interface_address(this, rta_oif, msg->rtm_family, NULL);
 	}
-	if (host)
-	{
-		this->mutex->lock(this->mutex);
-		if (!get_vip_refcount(this, host))
-		{	/* ignore routes added for virtual IPs */
-			fire_roam_event(this, FALSE);
-		}
-		this->mutex->unlock(this->mutex);
-		host->destroy(host);
+	if (!host || is_known_vip(this, host))
+	{	/* ignore routes added for virtual IPs */
+		this->lock->unlock(this->lock);
+		DESTROY_IF(host);
+		return;
 	}
+	this->lock->unlock(this->lock);
+	fire_roam_event(this, FALSE);
+	host->destroy(host);
 }
 
 /**
@@ -614,12 +1108,10 @@ static job_requeue_t receive_events(private_kernel_netlink_net_t *this)
 			case RTM_NEWADDR:
 			case RTM_DELADDR:
 				process_addr(this, hdr, TRUE);
-				this->condvar->broadcast(this->condvar);
 				break;
 			case RTM_NEWLINK:
 			case RTM_DELLINK:
 				process_link(this, hdr, TRUE);
-				this->condvar->broadcast(this->condvar);
 				break;
 			case RTM_NEWROUTE:
 			case RTM_DELROUTE:
@@ -639,10 +1131,8 @@ static job_requeue_t receive_events(private_kernel_netlink_net_t *this)
 /** enumerator over addresses */
 typedef struct {
 	private_kernel_netlink_net_t* this;
-	/** whether to enumerate down interfaces */
-	bool include_down_ifaces;
-	/** whether to enumerate virtual ip addresses */
-	bool include_virtual_ips;
+	/** which addresses to enumerate */
+	kernel_address_type_t which;
 } address_enumerator_t;
 
 /**
@@ -650,7 +1140,7 @@ typedef struct {
  */
 static void address_enumerator_destroy(address_enumerator_t *data)
 {
-	data->this->mutex->unlock(data->this->mutex);
+	data->this->lock->unlock(data->this->lock);
 	free(data);
 }
 
@@ -660,7 +1150,7 @@ static void address_enumerator_destroy(address_enumerator_t *data)
 static bool filter_addresses(address_enumerator_t *data,
 							 addr_entry_t** in, host_t** out)
 {
-	if (!data->include_virtual_ips && (*in)->virtual)
+	if (!(data->which & ADDR_TYPE_VIRTUAL) && (*in)->refcount)
 	{	/* skip virtual interfaces added by us */
 		return FALSE;
 	}
@@ -689,7 +1179,15 @@ static enumerator_t *create_iface_enumerator(iface_entry_t *iface,
 static bool filter_interfaces(address_enumerator_t *data, iface_entry_t** in,
 							  iface_entry_t** out)
 {
-	if (!data->include_down_ifaces && !((*in)->flags & IFF_UP))
+	if (!(data->which & ADDR_TYPE_IGNORED) && !(*in)->usable)
+	{	/* skip interfaces excluded by config */
+		return FALSE;
+	}
+	if (!(data->which & ADDR_TYPE_LOOPBACK) && ((*in)->flags & IFF_LOOPBACK))
+	{	/* ignore loopback devices */
+		return FALSE;
+	}
+	if (!(data->which & ADDR_TYPE_DOWN) && !((*in)->flags & IFF_UP))
 	{	/* skip interfaces not up */
 		return FALSE;
 	}
@@ -698,15 +1196,13 @@ static bool filter_interfaces(address_enumerator_t *data, iface_entry_t** in,
 }
 
 METHOD(kernel_net_t, create_address_enumerator, enumerator_t*,
-	private_kernel_netlink_net_t *this,
-	bool include_down_ifaces, bool include_virtual_ips)
+	private_kernel_netlink_net_t *this, kernel_address_type_t which)
 {
 	address_enumerator_t *data = malloc_thing(address_enumerator_t);
 	data->this = this;
-	data->include_down_ifaces = include_down_ifaces;
-	data->include_virtual_ips = include_virtual_ips;
+	data->which = which;
 
-	this->mutex->lock(this->mutex);
+	this->lock->read_lock(this->lock);
 	return enumerator_create_nested(
 				enumerator_create_filter(
 					this->ifaces->create_enumerator(this->ifaces),
@@ -715,47 +1211,40 @@ METHOD(kernel_net_t, create_address_enumerator, enumerator_t*,
 				(void*)address_enumerator_destroy);
 }
 
-METHOD(kernel_net_t, get_interface_name, char*,
-	private_kernel_netlink_net_t *this, host_t* ip)
+METHOD(kernel_net_t, get_interface_name, bool,
+	private_kernel_netlink_net_t *this, host_t* ip, char **name)
 {
-	enumerator_t *ifaces, *addrs;
-	iface_entry_t *iface;
-	addr_entry_t *addr;
-	char *name = NULL;
+	addr_map_entry_t *entry, lookup = {
+		.ip = ip,
+	};
 
-	DBG2(DBG_KNL, "getting interface name for %H", ip);
-
-	this->mutex->lock(this->mutex);
-	ifaces = this->ifaces->create_enumerator(this->ifaces);
-	while (ifaces->enumerate(ifaces, &iface))
+	if (ip->is_anyaddr(ip))
+	{
+		return FALSE;
+	}
+	this->lock->read_lock(this->lock);
+	/* first try to find it on an up and usable interface */
+	entry = this->addrs->get_match(this->addrs, &lookup,
+								  (void*)addr_map_entry_match_up_and_usable);
+	if (entry)
 	{
-		addrs = iface->addrs->create_enumerator(iface->addrs);
-		while (addrs->enumerate(addrs, &addr))
-		{
-			if (ip->ip_equals(ip, addr->ip))
-			{
-				name = strdup(iface->ifname);
-				break;
-			}
-		}
-		addrs->destroy(addrs);
 		if (name)
 		{
-			break;
+			*name = strdup(entry->iface->ifname);
+			DBG2(DBG_KNL, "%H is on interface %s", ip, *name);
 		}
+		this->lock->unlock(this->lock);
+		return TRUE;
 	}
-	ifaces->destroy(ifaces);
-	this->mutex->unlock(this->mutex);
-
-	if (name)
-	{
-		DBG2(DBG_KNL, "%H is on interface %s", ip, name);
-	}
-	else
+	/* maybe it is installed on an ignored interface */
+	entry = this->addrs->get_match(this->addrs, &lookup,
+								  (void*)addr_map_entry_match_up);
+	if (!entry)
 	{
-		DBG2(DBG_KNL, "%H is not a local address", ip);
+		DBG2(DBG_KNL, "%H is not a local address or the interface is down", ip);
 	}
-	return name;
+	this->lock->unlock(this->lock);
+	return FALSE;
 }
 
 /**
@@ -763,24 +1252,18 @@ METHOD(kernel_net_t, get_interface_name, char*,
  */
 static int get_interface_index(private_kernel_netlink_net_t *this, char* name)
 {
-	enumerator_t *ifaces;
 	iface_entry_t *iface;
 	int ifindex = 0;
 
 	DBG2(DBG_KNL, "getting iface index for %s", name);
 
-	this->mutex->lock(this->mutex);
-	ifaces = this->ifaces->create_enumerator(this->ifaces);
-	while (ifaces->enumerate(ifaces, &iface))
+	this->lock->read_lock(this->lock);
+	if (this->ifaces->find_first(this->ifaces, (void*)iface_entry_by_name,
+								(void**)&iface, name) == SUCCESS)
 	{
-		if (streq(name, iface->ifname))
-		{
-			ifindex = iface->ifindex;
-			break;
-		}
+		ifindex = iface->ifindex;
 	}
-	ifaces->destroy(ifaces);
-	this->mutex->unlock(this->mutex);
+	this->lock->unlock(this->lock);
 
 	if (ifindex == 0)
 	{
@@ -790,29 +1273,6 @@ static int get_interface_index(private_kernel_netlink_net_t *this, char* name)
 }
 
 /**
- * Check if an interface with a given index is up
- */
-static bool is_interface_up(private_kernel_netlink_net_t *this, int index)
-{
-	enumerator_t *ifaces;
-	iface_entry_t *iface;
-	/* default to TRUE for interface we do not monitor (e.g. lo) */
-	bool up = TRUE;
-
-	ifaces = this->ifaces->create_enumerator(this->ifaces);
-	while (ifaces->enumerate(ifaces, &iface))
-	{
-		if (iface->ifindex == index)
-		{
-			up = iface->flags & IFF_UP;
-			break;
-		}
-	}
-	ifaces->destroy(ifaces);
-	return up;
-}
-
-/**
  * check if an address (chunk) addr is in subnet (net with net_len net bits)
  */
 static bool addr_in_subnet(chunk_t addr, chunk_t net, int net_len)
@@ -849,6 +1309,94 @@ static bool addr_in_subnet(chunk_t addr, chunk_t net, int net_len)
 }
 
 /**
+ * Store information about a route retrieved via RTNETLINK
+ */
+typedef struct {
+	chunk_t gtw;
+	chunk_t src;
+	chunk_t dst;
+	host_t *src_host;
+	u_int8_t dst_len;
+	u_int32_t table;
+	u_int32_t oif;
+} rt_entry_t;
+
+/**
+ * Free a route entry
+ */
+static void rt_entry_destroy(rt_entry_t *this)
+{
+	DESTROY_IF(this->src_host);
+	free(this);
+}
+
+/**
+ * Parse route received with RTM_NEWROUTE. The given rt_entry_t object will be
+ * reused if not NULL.
+ *
+ * Returned chunks point to internal data of the Netlink message.
+ */
+static rt_entry_t *parse_route(struct nlmsghdr *hdr, rt_entry_t *route)
+{
+	struct rtattr *rta;
+	struct rtmsg *msg;
+	size_t rtasize;
+
+	msg = (struct rtmsg*)(NLMSG_DATA(hdr));
+	rta = RTM_RTA(msg);
+	rtasize = RTM_PAYLOAD(hdr);
+
+	if (route)
+	{
+		route->gtw = chunk_empty;
+		route->src = chunk_empty;
+		route->dst = chunk_empty;
+		route->dst_len = msg->rtm_dst_len;
+		route->table = msg->rtm_table;
+		route->oif = 0;
+	}
+	else
+	{
+		INIT(route,
+			.dst_len = msg->rtm_dst_len,
+			.table = msg->rtm_table,
+		);
+	}
+
+	while (RTA_OK(rta, rtasize))
+	{
+		switch (rta->rta_type)
+		{
+			case RTA_PREFSRC:
+				route->src = chunk_create(RTA_DATA(rta), RTA_PAYLOAD(rta));
+				break;
+			case RTA_GATEWAY:
+				route->gtw = chunk_create(RTA_DATA(rta), RTA_PAYLOAD(rta));
+				break;
+			case RTA_DST:
+				route->dst = chunk_create(RTA_DATA(rta), RTA_PAYLOAD(rta));
+				break;
+			case RTA_OIF:
+				if (RTA_PAYLOAD(rta) == sizeof(route->oif))
+				{
+					route->oif = *(u_int32_t*)RTA_DATA(rta);
+				}
+				break;
+#ifdef HAVE_RTA_TABLE
+			case RTA_TABLE:
+				if (RTA_PAYLOAD(rta) == sizeof(route->table))
+				{
+					route->table = *(u_int32_t*)RTA_DATA(rta);
+				}
+				break;
+#endif /* HAVE_RTA_TABLE*/
+		}
+		rta = RTA_NEXT(rta, rtasize);
+	}
+	return route;
+}
+
+/**
  * Get a route: If "nexthop", the nexthop is returned. source addr otherwise.
  */
 static host_t *get_route(private_kernel_netlink_net_t *this, host_t *dest,
@@ -859,22 +1407,21 @@ static host_t *get_route(private_kernel_netlink_net_t *this, host_t *dest,
 	struct rtmsg *msg;
 	chunk_t chunk;
 	size_t len;
-	int best = -1;
+	linked_list_t *routes;
+	rt_entry_t *route = NULL, *best = NULL;
 	enumerator_t *enumerator;
-	host_t *src = NULL, *gtw = NULL;
-
-	DBG2(DBG_KNL, "getting address to reach %H", dest);
+	host_t *addr = NULL;
 
 	memset(&request, 0, sizeof(request));
 
 	hdr = (struct nlmsghdr*)request;
 	hdr->nlmsg_flags = NLM_F_REQUEST;
-	if (dest->get_family(dest) == AF_INET)
-	{
-		/* We dump all addresses for IPv4, as we want to ignore IPsec specific
-		 * routes installed by us. But the kernel does not return source
-		 * addresses in a IPv6 dump, so fall back to get() for v6 routes. */
-		hdr->nlmsg_flags |= NLM_F_ROOT | NLM_F_DUMP;
+	if (dest->get_family(dest) == AF_INET || this->rta_prefsrc_for_ipv6 ||
+		this->routing_table)
+	{	/* kernels prior to 3.0 do not support RTA_PREFSRC for IPv6 routes.
+		 * as we want to ignore routes with virtual IPs we cannot use DUMP
+		 * if these routes are not installed in a separate table */
+		hdr->nlmsg_flags |= NLM_F_DUMP;
 	}
 	hdr->nlmsg_type = RTM_GETROUTE;
 	hdr->nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
@@ -891,10 +1438,12 @@ static host_t *get_route(private_kernel_netlink_net_t *this, host_t *dest,
 
 	if (this->socket->send(this->socket, hdr, &out, &len) != SUCCESS)
 	{
-		DBG1(DBG_KNL, "getting address to %H failed", dest);
+		DBG2(DBG_KNL, "getting %s to reach %H failed",
+			 nexthop ? "nexthop" : "address", dest);
 		return NULL;
 	}
-	this->mutex->lock(this->mutex);
+	routes = linked_list_create();
+	this->lock->read_lock(this->lock);
 
 	for (current = out; NLMSG_OK(current, len);
 		 current = NLMSG_NEXT(current, len))
@@ -905,132 +1454,53 @@ static host_t *get_route(private_kernel_netlink_net_t *this, host_t *dest,
 				break;
 			case RTM_NEWROUTE:
 			{
-				struct rtattr *rta;
-				size_t rtasize;
-				chunk_t rta_gtw, rta_src, rta_dst;
-				u_int32_t rta_oif = 0, rta_table;
-				host_t *new_src, *new_gtw;
-				bool cont = FALSE;
+				rt_entry_t *other;
 				uintptr_t table;
 
-				rta_gtw = rta_src = rta_dst = chunk_empty;
-				msg = (struct rtmsg*)(NLMSG_DATA(current));
-				rta = RTM_RTA(msg);
-				rtasize = RTM_PAYLOAD(current);
-				rta_table = msg->rtm_table;
-				while (RTA_OK(rta, rtasize))
-				{
-					switch (rta->rta_type)
-					{
-						case RTA_PREFSRC:
-							rta_src = chunk_create(RTA_DATA(rta), RTA_PAYLOAD(rta));
-							break;
-						case RTA_GATEWAY:
-							rta_gtw = chunk_create(RTA_DATA(rta), RTA_PAYLOAD(rta));
-							break;
-						case RTA_DST:
-							rta_dst = chunk_create(RTA_DATA(rta), RTA_PAYLOAD(rta));
-							break;
-						case RTA_OIF:
-							if (RTA_PAYLOAD(rta) == sizeof(rta_oif))
-							{
-								rta_oif = *(u_int32_t*)RTA_DATA(rta);
-							}
-							break;
-#ifdef HAVE_RTA_TABLE
-						case RTA_TABLE:
-							if (RTA_PAYLOAD(rta) == sizeof(rta_table))
-							{
-								rta_table = *(u_int32_t*)RTA_DATA(rta);
-							}
-							break;
-#endif /* HAVE_RTA_TABLE*/
-					}
-					rta = RTA_NEXT(rta, rtasize);
-				}
-				if (msg->rtm_dst_len <= best)
-				{	/* not better than a previous one */
-					continue;
-				}
-				enumerator = this->rt_exclude->create_enumerator(this->rt_exclude);
-				while (enumerator->enumerate(enumerator, &table))
-				{
-					if (table == rta_table)
-					{
-						cont = TRUE;
-						break;
-					}
-				}
-				enumerator->destroy(enumerator);
-				if (cont)
-				{
+				route = parse_route(current, route);
+
+				table = (uintptr_t)route->table;
+				if (this->rt_exclude->find_first(this->rt_exclude, NULL,
+												 (void**)&table) == SUCCESS)
+				{	/* route is from an excluded routing table */
 					continue;
 				}
 				if (this->routing_table != 0 &&
-					rta_table == this->routing_table)
+					route->table == this->routing_table)
 				{	/* route is from our own ipsec routing table */
 					continue;
 				}
-				if (rta_oif && !is_interface_up(this, rta_oif))
+				if (route->oif && !is_interface_up_and_usable(this, route->oif))
 				{	/* interface is down */
 					continue;
 				}
-				if (!addr_in_subnet(chunk, rta_dst, msg->rtm_dst_len))
+				if (!addr_in_subnet(chunk, route->dst, route->dst_len))
 				{	/* route destination does not contain dest */
 					continue;
 				}
-
-				if (nexthop)
-				{
-					/* nexthop lookup, return gateway if any */
-					DESTROY_IF(gtw);
-					gtw = host_create_from_chunk(msg->rtm_family, rta_gtw, 0);
-					best = msg->rtm_dst_len;
-					continue;
-				}
-				if (rta_src.ptr)
-				{	/* got a source address */
-					new_src = host_create_from_chunk(msg->rtm_family, rta_src, 0);
-					if (new_src)
-					{
-						if (get_vip_refcount(this, new_src))
-						{	/* skip source address if it is installed by us */
-							new_src->destroy(new_src);
-						}
-						else
-						{
-							DESTROY_IF(src);
-							src = new_src;
-							best = msg->rtm_dst_len;
-						}
-					}
-					continue;
-				}
-				if (rta_oif)
-				{	/* no src or gtw, but an interface. Get address from it. */
-					new_src = get_interface_address(this, rta_oif,
-													msg->rtm_family);
-					if (new_src)
-					{
-						DESTROY_IF(src);
-						src = new_src;
-						best = msg->rtm_dst_len;
+				if (route->src.ptr)
+				{	/* verify source address, if any */
+					host_t *src = host_create_from_chunk(msg->rtm_family,
+														 route->src, 0);
+					if (src && is_known_vip(this, src))
+					{	/* ignore routes installed by us */
+						src->destroy(src);
+						continue;
 					}
-					continue;
+					route->src_host = src;
 				}
-				if (rta_gtw.ptr)
-				{	/* no source, but a gateway. Lookup source to reach gtw. */
-					new_gtw = host_create_from_chunk(msg->rtm_family, rta_gtw, 0);
-					new_src = get_route(this, new_gtw, FALSE, candidate);
-					new_gtw->destroy(new_gtw);
-					if (new_src)
+				/* insert route, sorted by decreasing network prefix */
+				enumerator = routes->create_enumerator(routes);
+				while (enumerator->enumerate(enumerator, &other))
+				{
+					if (route->dst_len > other->dst_len)
 					{
-						DESTROY_IF(src);
-						src = new_src;
-						best = msg->rtm_dst_len;
+						break;
 					}
-					continue;
 				}
+				routes->insert_before(routes, enumerator, route);
+				enumerator->destroy(enumerator);
+				route = NULL;
 				continue;
 			}
 			default:
@@ -1038,18 +1508,111 @@ static host_t *get_route(private_kernel_netlink_net_t *this, host_t *dest,
 		}
 		break;
 	}
-	free(out);
-	this->mutex->unlock(this->mutex);
+	if (route)
+	{
+		rt_entry_destroy(route);
+	}
+
+	/* now we have a list of routes matching dest, sorted by net prefix.
+	 * we will look for source addresses for these routes and select the one
+	 * with the preferred source address, if possible */
+	enumerator = routes->create_enumerator(routes);
+	while (enumerator->enumerate(enumerator, &route))
+	{
+		if (route->src_host)
+		{	/* got a source address with the route, if no preferred source
+			 * is given or it matches we are done, as this is the best route */
+			if (!candidate || candidate->ip_equals(candidate, route->src_host))
+			{
+				best = route;
+				break;
+			}
+			else if (route->oif)
+			{	/* no match yet, maybe it is assigned to the same interface */
+				host_t *src = get_interface_address(this, route->oif,
+													msg->rtm_family, candidate);
+				if (src && src->ip_equals(src, candidate))
+				{
+					route->src_host->destroy(route->src_host);
+					route->src_host = src;
+					best = route;
+					break;
+				}
+				DESTROY_IF(src);
+			}
+			/* no luck yet with the source address. if this is the best (first)
+			 * route we store it as fallback in case we don't find a route with
+			 * the preferred source */
+			best = best ?: route;
+			continue;
+		}
+		if (route->oif)
+		{	/* no src, but an interface - get address from it */
+			route->src_host = get_interface_address(this, route->oif,
+													msg->rtm_family, candidate);
+			if (route->src_host)
+			{	/* we handle this address the same as the one above */
+				if (!candidate ||
+					 candidate->ip_equals(candidate, route->src_host))
+				{
+					best = route;
+					break;
+				}
+				best = best ?: route;
+				continue;
+			}
+		}
+		if (route->gtw.ptr)
+		{	/* no src, no iface, but a gateway - lookup src to reach gtw */
+			host_t *gtw;
+
+			gtw = host_create_from_chunk(msg->rtm_family, route->gtw, 0);
+			route->src_host = get_route(this, gtw, FALSE, candidate);
+			gtw->destroy(gtw);
+			if (route->src_host)
+			{	/* more of the same */
+				if (!candidate ||
+					 candidate->ip_equals(candidate, route->src_host))
+				{
+					best = route;
+					break;
+				}
+				best = best ?: route;
+			}
+		}
+	}
+	enumerator->destroy(enumerator);
 
 	if (nexthop)
+	{	/* nexthop lookup, return gateway if any */
+		if (best || routes->get_first(routes, (void**)&best) == SUCCESS)
+		{
+			addr = host_create_from_chunk(msg->rtm_family, best->gtw, 0);
+		}
+		addr = addr ?: dest->clone(dest);
+	}
+	else
 	{
-		if (gtw)
+		if (best)
 		{
-			return gtw;
+			addr = best->src_host->clone(best->src_host);
 		}
-		return dest->clone(dest);
 	}
-	return src;
+	this->lock->unlock(this->lock);
+	routes->destroy_function(routes, (void*)rt_entry_destroy);
+	free(out);
+
+	if (addr)
+	{
+		DBG2(DBG_KNL, "using %H as %s to reach %H", addr,
+			 nexthop ? "nexthop" : "address", dest);
+	}
+	else
+	{
+		DBG2(DBG_KNL, "no %s found to reach %H",
+			 nexthop ? "nexthop" : "address", dest);
+	}
+	return addr;
 }
 
 METHOD(kernel_net_t, get_source_addr, host_t*,
@@ -1059,9 +1622,9 @@ METHOD(kernel_net_t, get_source_addr, host_t*,
 }
 
 METHOD(kernel_net_t, get_nexthop, host_t*,
-	private_kernel_netlink_net_t *this, host_t *dest)
+	private_kernel_netlink_net_t *this, host_t *dest, host_t *src)
 {
-	return get_route(this, dest, TRUE, NULL);
+	return get_route(this, dest, TRUE, src);
 }
 
 /**
@@ -1100,87 +1663,109 @@ static status_t manage_ipaddr(private_kernel_netlink_net_t *this, int nlmsg_type
 METHOD(kernel_net_t, add_ip, status_t,
 	private_kernel_netlink_net_t *this, host_t *virtual_ip, host_t *iface_ip)
 {
-	iface_entry_t *iface;
-	addr_entry_t *addr;
-	enumerator_t *addrs, *ifaces;
-	int ifindex;
+	addr_map_entry_t *entry, lookup = {
+		.ip = virtual_ip,
+	};
+	iface_entry_t *iface = NULL;
 
 	if (!this->install_virtual_ip)
 	{	/* disabled by config */
 		return SUCCESS;
 	}
 
-	DBG2(DBG_KNL, "adding virtual IP %H", virtual_ip);
-
-	this->mutex->lock(this->mutex);
-	ifaces = this->ifaces->create_enumerator(this->ifaces);
-	while (ifaces->enumerate(ifaces, &iface))
-	{
-		bool iface_found = FALSE;
-
-		addrs = iface->addrs->create_enumerator(iface->addrs);
-		while (addrs->enumerate(addrs, &addr))
-		{
-			if (iface_ip->ip_equals(iface_ip, addr->ip))
+	this->lock->write_lock(this->lock);
+	/* the virtual IP might actually be installed as regular IP, in which case
+	 * we don't track it as virtual IP */
+	entry = this->addrs->get_match(this->addrs, &lookup,
+								  (void*)addr_map_entry_match);
+	if (!entry)
+	{	/* otherwise it might already be installed as virtual IP */
+		entry = this->vips->get_match(this->vips, &lookup,
+									 (void*)addr_map_entry_match);
+		if (entry)
+		{	/* the vip we found can be in one of three states: 1) installed and
+			 * ready, 2) just added by another thread, but not yet confirmed to
+			 * be installed by the kernel, 3) just deleted, but not yet gone.
+			 * Then while we wait below, several things could happen (as we
+			 * release the lock).  For instance, the interface could disappear,
+			 * or the IP is finally deleted, and it reappears on a different
+			 * interface. All these cases are handled by the call below. */
+			while (!is_vip_installed_or_gone(this, virtual_ip, &entry))
 			{
-				iface_found = TRUE;
+				this->condvar->wait(this->condvar, this->lock);
 			}
-			else if (virtual_ip->ip_equals(virtual_ip, addr->ip))
+			if (entry)
 			{
-				addr->refcount++;
-				DBG2(DBG_KNL, "virtual IP %H already installed on %s",
-					 virtual_ip, iface->ifname);
-				addrs->destroy(addrs);
-				ifaces->destroy(ifaces);
-				this->mutex->unlock(this->mutex);
-				return SUCCESS;
+				entry->addr->refcount++;
 			}
 		}
-		addrs->destroy(addrs);
-
-		if (iface_found)
+	}
+	if (entry)
+	{
+		DBG2(DBG_KNL, "virtual IP %H is already installed on %s", virtual_ip,
+			 entry->iface->ifname);
+		this->lock->unlock(this->lock);
+		return SUCCESS;
+	}
+	/* try to find the target interface, either by config or via src ip */
+	if (!this->install_virtual_ip_on ||
+		 this->ifaces->find_first(this->ifaces, (void*)iface_entry_by_name,
+						(void**)&iface, this->install_virtual_ip_on) != SUCCESS)
+	{
+		lookup.ip = iface_ip;
+		entry = this->addrs->get_match(this->addrs, &lookup,
+									  (void*)addr_map_entry_match);
+		if (!entry)
+		{	/* if we don't find the requested interface we just use the first */
+			this->ifaces->get_first(this->ifaces, (void**)&iface);
+		}
+		else
 		{
-			ifindex = iface->ifindex;
-			addr = malloc_thing(addr_entry_t);
-			addr->ip = virtual_ip->clone(virtual_ip);
-			addr->refcount = 0;
-			addr->virtual = TRUE;
-			addr->scope = RT_SCOPE_UNIVERSE;
-			iface->addrs->insert_last(iface->addrs, addr);
-
-			if (manage_ipaddr(this, RTM_NEWADDR, NLM_F_CREATE | NLM_F_EXCL,
-							  ifindex, virtual_ip) == SUCCESS)
-			{
-				while (get_vip_refcount(this, virtual_ip) == 0)
-				{	/* wait until address appears */
-					this->condvar->wait(this->condvar, this->mutex);
-				}
-				ifaces->destroy(ifaces);
-				this->mutex->unlock(this->mutex);
+			iface = entry->iface;
+		}
+	}
+	if (iface)
+	{
+		addr_entry_t *addr;
+
+		INIT(addr,
+			.ip = virtual_ip->clone(virtual_ip),
+			.refcount = 1,
+			.scope = RT_SCOPE_UNIVERSE,
+		);
+		iface->addrs->insert_last(iface->addrs, addr);
+		addr_map_entry_add(this->vips, addr, iface);
+		if (manage_ipaddr(this, RTM_NEWADDR, NLM_F_CREATE | NLM_F_EXCL,
+						  iface->ifindex, virtual_ip) == SUCCESS)
+		{
+			while (!is_vip_installed_or_gone(this, virtual_ip, &entry))
+			{	/* wait until address appears */
+				this->condvar->wait(this->condvar, this->lock);
+			}
+			if (entry)
+			{	/* we fail if the interface got deleted in the meantime */
+				DBG2(DBG_KNL, "virtual IP %H installed on %s", virtual_ip,
+					 entry->iface->ifname);
+				this->lock->unlock(this->lock);
 				return SUCCESS;
 			}
-			ifaces->destroy(ifaces);
-			this->mutex->unlock(this->mutex);
-			DBG1(DBG_KNL, "adding virtual IP %H failed", virtual_ip);
-			return FAILED;
 		}
+		this->lock->unlock(this->lock);
+		DBG1(DBG_KNL, "adding virtual IP %H failed", virtual_ip);
+		return FAILED;
 	}
-	ifaces->destroy(ifaces);
-	this->mutex->unlock(this->mutex);
-
-	DBG1(DBG_KNL, "interface address %H not found, unable to install"
-		 "virtual IP %H", iface_ip, virtual_ip);
+	this->lock->unlock(this->lock);
+	DBG1(DBG_KNL, "no interface available, unable to install virtual IP %H",
+		 virtual_ip);
 	return FAILED;
 }
 
 METHOD(kernel_net_t, del_ip, status_t,
 	private_kernel_netlink_net_t *this, host_t *virtual_ip)
 {
-	iface_entry_t *iface;
-	addr_entry_t *addr;
-	enumerator_t *addrs, *ifaces;
-	status_t status;
-	int ifindex;
+	addr_map_entry_t *entry, lookup = {
+		.ip = virtual_ip,
+	};
 
 	if (!this->install_virtual_ip)
 	{	/* disabled by config */
@@ -1189,60 +1774,61 @@ METHOD(kernel_net_t, del_ip, status_t,
 
 	DBG2(DBG_KNL, "deleting virtual IP %H", virtual_ip);
 
-	this->mutex->lock(this->mutex);
-	ifaces = this->ifaces->create_enumerator(this->ifaces);
-	while (ifaces->enumerate(ifaces, &iface))
-	{
-		addrs = iface->addrs->create_enumerator(iface->addrs);
-		while (addrs->enumerate(addrs, &addr))
+	this->lock->write_lock(this->lock);
+	entry = this->vips->get_match(this->vips, &lookup,
+								 (void*)addr_map_entry_match);
+	if (!entry)
+	{	/* we didn't install this IP as virtual IP */
+		entry = this->addrs->get_match(this->addrs, &lookup,
+									  (void*)addr_map_entry_match);
+		if (entry)
 		{
-			if (virtual_ip->ip_equals(virtual_ip, addr->ip))
+			DBG2(DBG_KNL, "not deleting existing IP %H on %s", virtual_ip,
+				 entry->iface->ifname);
+			this->lock->unlock(this->lock);
+			return SUCCESS;
+		}
+		DBG2(DBG_KNL, "virtual IP %H not cached, unable to delete", virtual_ip);
+		this->lock->unlock(this->lock);
+		return FAILED;
+	}
+	if (entry->addr->refcount == 1)
+	{
+		status_t status;
+
+		/* we set this flag so that threads calling add_ip will block and wait
+		 * until the entry is gone, also so we can wait below */
+		entry->addr->installed = FALSE;
+		status = manage_ipaddr(this, RTM_DELADDR, 0, entry->iface->ifindex,
+							   virtual_ip);
+		if (status == SUCCESS)
+		{	/* wait until the address is really gone */
+			while (is_known_vip(this, virtual_ip))
 			{
-				ifindex = iface->ifindex;
-				if (addr->refcount == 1)
-				{
-					status = manage_ipaddr(this, RTM_DELADDR, 0,
-										   ifindex, virtual_ip);
-					if (status == SUCCESS)
-					{	/* wait until the address is really gone */
-						while (get_vip_refcount(this, virtual_ip) > 0)
-						{
-							this->condvar->wait(this->condvar, this->mutex);
-						}
-					}
-					addrs->destroy(addrs);
-					ifaces->destroy(ifaces);
-					this->mutex->unlock(this->mutex);
-					return status;
-				}
-				else
-				{
-					addr->refcount--;
-				}
-				DBG2(DBG_KNL, "virtual IP %H used by other SAs, not deleting",
-					 virtual_ip);
-				addrs->destroy(addrs);
-				ifaces->destroy(ifaces);
-				this->mutex->unlock(this->mutex);
-				return SUCCESS;
+				this->condvar->wait(this->condvar, this->lock);
 			}
 		}
-		addrs->destroy(addrs);
+		this->lock->unlock(this->lock);
+		return status;
 	}
-	ifaces->destroy(ifaces);
-	this->mutex->unlock(this->mutex);
-
-	DBG2(DBG_KNL, "virtual IP %H not cached, unable to delete", virtual_ip);
-	return FAILED;
+	else
+	{
+		entry->addr->refcount--;
+	}
+	DBG2(DBG_KNL, "virtual IP %H used by other SAs, not deleting",
+		 virtual_ip);
+	this->lock->unlock(this->lock);
+	return SUCCESS;
 }
 
 /**
  * Manages source routes in the routing table.
  * By setting the appropriate nlmsg_type, the route gets added or removed.
  */
-static status_t manage_srcroute(private_kernel_netlink_net_t *this, int nlmsg_type,
-								int flags, chunk_t dst_net, u_int8_t prefixlen,
-								host_t *gateway, host_t *src_ip, char *if_name)
+static status_t manage_srcroute(private_kernel_netlink_net_t *this,
+								int nlmsg_type, int flags, chunk_t dst_net,
+								u_int8_t prefixlen, host_t *gateway,
+								host_t *src_ip, char *if_name)
 {
 	netlink_buf_t request;
 	struct nlmsghdr *hdr;
@@ -1306,16 +1892,56 @@ METHOD(kernel_net_t, add_route, status_t,
 	private_kernel_netlink_net_t *this, chunk_t dst_net, u_int8_t prefixlen,
 	host_t *gateway, host_t *src_ip, char *if_name)
 {
-	return manage_srcroute(this, RTM_NEWROUTE, NLM_F_CREATE | NLM_F_EXCL,
-				dst_net, prefixlen, gateway, src_ip, if_name);
+	status_t status;
+	route_entry_t *found, route = {
+		.dst_net = dst_net,
+		.prefixlen = prefixlen,
+		.gateway = gateway,
+		.src_ip = src_ip,
+		.if_name = if_name,
+	};
+
+	this->routes_lock->lock(this->routes_lock);
+	found = this->routes->get(this->routes, &route);
+	if (found)
+	{
+		this->routes_lock->unlock(this->routes_lock);
+		return ALREADY_DONE;
+	}
+	found = route_entry_clone(&route);
+	this->routes->put(this->routes, found, found);
+	status = manage_srcroute(this, RTM_NEWROUTE, NLM_F_CREATE | NLM_F_EXCL,
+							 dst_net, prefixlen, gateway, src_ip, if_name);
+	this->routes_lock->unlock(this->routes_lock);
+	return status;
 }
 
 METHOD(kernel_net_t, del_route, status_t,
 	private_kernel_netlink_net_t *this, chunk_t dst_net, u_int8_t prefixlen,
 	host_t *gateway, host_t *src_ip, char *if_name)
 {
-	return manage_srcroute(this, RTM_DELROUTE, 0, dst_net, prefixlen,
-				gateway, src_ip, if_name);
+	status_t status;
+	route_entry_t *found, route = {
+		.dst_net = dst_net,
+		.prefixlen = prefixlen,
+		.gateway = gateway,
+		.src_ip = src_ip,
+		.if_name = if_name,
+	};
+
+	this->routes_lock->lock(this->routes_lock);
+	found = this->routes->get(this->routes, &route);
+	if (!found)
+	{
+		this->routes_lock->unlock(this->routes_lock);
+		return NOT_FOUND;
+	}
+	this->routes->remove(this->routes, found);
+	route_entry_destroy(found);
+	status = manage_srcroute(this, RTM_DELROUTE, 0, dst_net, prefixlen,
+							 gateway, src_ip, if_name);
+	this->routes_lock->unlock(this->routes_lock);
+	return status;
 }
 
 /**
@@ -1331,7 +1957,7 @@ static status_t init_address_list(private_kernel_netlink_net_t *this)
 	iface_entry_t *iface;
 	addr_entry_t *addr;
 
-	DBG1(DBG_KNL, "listening on interfaces:");
+	DBG2(DBG_KNL, "known interfaces and IP addresses:");
 
 	memset(&request, 0, sizeof(request));
 
@@ -1389,23 +2015,23 @@ static status_t init_address_list(private_kernel_netlink_net_t *this)
 	}
 	free(out);
 
-	this->mutex->lock(this->mutex);
+	this->lock->read_lock(this->lock);
 	ifaces = this->ifaces->create_enumerator(this->ifaces);
 	while (ifaces->enumerate(ifaces, &iface))
 	{
-		if (iface->flags & IFF_UP)
+		if (iface_entry_up_and_usable(iface))
 		{
-			DBG1(DBG_KNL, "  %s", iface->ifname);
+			DBG2(DBG_KNL, "  %s", iface->ifname);
 			addrs = iface->addrs->create_enumerator(iface->addrs);
 			while (addrs->enumerate(addrs, (void**)&addr))
 			{
-				DBG1(DBG_KNL, "    %H", addr->ip);
+				DBG2(DBG_KNL, "    %H", addr->ip);
 			}
 			addrs->destroy(addrs);
 		}
 	}
 	ifaces->destroy(ifaces);
-	this->mutex->unlock(this->mutex);
+	this->lock->unlock(this->lock);
 	return SUCCESS;
 }
 
@@ -1443,9 +2069,59 @@ static status_t manage_rule(private_kernel_netlink_net_t *this, int nlmsg_type,
 	return this->socket->send_ack(this->socket, hdr);
 }
 
+/**
+ * check for kernel features (currently only via version number)
+ */
+static void check_kernel_features(private_kernel_netlink_net_t *this)
+{
+	struct utsname utsname;
+	int a, b, c;
+
+	if (uname(&utsname) == 0)
+	{
+		switch(sscanf(utsname.release, "%d.%d.%d", &a, &b, &c))
+		{
+			case 3:
+				if (a == 2)
+				{
+					DBG2(DBG_KNL, "detected Linux %d.%d.%d, no support for "
+						 "RTA_PREFSRC for IPv6 routes", a, b, c);
+					break;
+				}
+				/* fall-through */
+			case 2:
+				/* only 3.x+ uses two part version numbers */
+				this->rta_prefsrc_for_ipv6 = TRUE;
+				break;
+			default:
+				break;
+		}
+	}
+}
+
+/**
+ * Destroy an address to iface map
+ */
+static void addr_map_destroy(hashtable_t *map)
+{
+	enumerator_t *enumerator;
+	addr_map_entry_t *addr;
+
+	enumerator = map->create_enumerator(map);
+	while (enumerator->enumerate(enumerator, NULL, (void**)&addr))
+	{
+		free(addr);
+	}
+	enumerator->destroy(enumerator);
+	map->destroy(map);
+}
+
 METHOD(kernel_net_t, destroy, void,
 	private_kernel_netlink_net_t *this)
 {
+	enumerator_t *enumerator;
+	route_entry_t *route;
+
 	if (this->routing_table)
 	{
 		manage_rule(this, RTM_DELRULE, AF_INET, this->routing_table,
@@ -1453,19 +2129,34 @@ METHOD(kernel_net_t, destroy, void,
 		manage_rule(this, RTM_DELRULE, AF_INET6, this->routing_table,
 					this->routing_table_prio);
 	}
-	if (this->job)
-	{
-		this->job->cancel(this->job);
-	}
 	if (this->socket_events > 0)
 	{
 		close(this->socket_events);
 	}
+	enumerator = this->routes->create_enumerator(this->routes);
+	while (enumerator->enumerate(enumerator, NULL, (void**)&route))
+	{
+		manage_srcroute(this, RTM_DELROUTE, 0, route->dst_net, route->prefixlen,
+						route->gateway, route->src_ip, route->if_name);
+		route_entry_destroy(route);
+	}
+	enumerator->destroy(enumerator);
+	this->routes->destroy(this->routes);
+	this->routes_lock->destroy(this->routes_lock);
 	DESTROY_IF(this->socket);
+
+	net_changes_clear(this);
+	this->net_changes->destroy(this->net_changes);
+	this->net_changes_lock->destroy(this->net_changes_lock);
+
+	addr_map_destroy(this->addrs);
+	addr_map_destroy(this->vips);
+
 	this->ifaces->destroy_function(this->ifaces, (void*)iface_entry_destroy);
 	this->rt_exclude->destroy(this->rt_exclude);
+	this->roam_lock->destroy(this->roam_lock);
 	this->condvar->destroy(this->condvar);
-	this->mutex->destroy(this->mutex);
+	this->lock->destroy(this->lock);
 	free(this);
 }
 
@@ -1475,8 +2166,8 @@ METHOD(kernel_net_t, destroy, void,
 kernel_netlink_net_t *kernel_netlink_net_create()
 {
 	private_kernel_netlink_net_t *this;
-	struct sockaddr_nl addr;
 	enumerator_t *enumerator;
+	bool register_for_events = TRUE;
 	char *exclude;
 
 	INIT(this,
@@ -1495,9 +2186,22 @@ kernel_netlink_net_t *kernel_netlink_net_create()
 		},
 		.socket = netlink_socket_create(NETLINK_ROUTE),
 		.rt_exclude = linked_list_create(),
+		.routes = hashtable_create((hashtable_hash_t)route_entry_hash,
+								   (hashtable_equals_t)route_entry_equals, 16),
+		.net_changes = hashtable_create(
+								   (hashtable_hash_t)net_change_hash,
+								   (hashtable_equals_t)net_change_equals, 16),
+		.addrs = hashtable_create(
+								(hashtable_hash_t)addr_map_entry_hash,
+								(hashtable_equals_t)addr_map_entry_equals, 16),
+		.vips = hashtable_create((hashtable_hash_t)addr_map_entry_hash,
+								 (hashtable_equals_t)addr_map_entry_equals, 16),
+		.routes_lock = mutex_create(MUTEX_TYPE_DEFAULT),
+		.net_changes_lock = mutex_create(MUTEX_TYPE_DEFAULT),
 		.ifaces = linked_list_create(),
-		.mutex = mutex_create(MUTEX_TYPE_RECURSIVE),
-		.condvar = condvar_create(CONDVAR_TYPE_DEFAULT),
+		.lock = rwlock_create(RWLOCK_TYPE_DEFAULT),
+		.condvar = rwlock_condvar_create(),
+		.roam_lock = spinlock_create(),
 		.routing_table = lib->settings->get_int(lib->settings,
 				"%s.routing_table", ROUTING_TABLE, hydra->daemon),
 		.routing_table_prio = lib->settings->get_int(lib->settings,
@@ -1506,8 +2210,18 @@ kernel_netlink_net_t *kernel_netlink_net_create()
 				"%s.process_route", TRUE, hydra->daemon),
 		.install_virtual_ip = lib->settings->get_bool(lib->settings,
 				"%s.install_virtual_ip", TRUE, hydra->daemon),
+		.install_virtual_ip_on = lib->settings->get_str(lib->settings,
+				"%s.install_virtual_ip_on", NULL, hydra->daemon),
 	);
-	timerclear(&this->last_roam);
+	timerclear(&this->last_route_reinstall);
+	timerclear(&this->next_roam);
+
+	check_kernel_features(this);
+
+	if (streq(hydra->daemon, "starter"))
+	{	/* starter has no threads, so we do not register for kernel events */
+		register_for_events = FALSE;
+	}
 
 	exclude = lib->settings->get_str(lib->settings,
 					"%s.ignore_routing_tables", NULL, hydra->daemon);
@@ -1530,29 +2244,35 @@ kernel_netlink_net_t *kernel_netlink_net_create()
 		enumerator->destroy(enumerator);
 	}
 
-	memset(&addr, 0, sizeof(addr));
-	addr.nl_family = AF_NETLINK;
-
-	/* create and bind RT socket for events (address/interface/route changes) */
-	this->socket_events = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
-	if (this->socket_events < 0)
+	if (register_for_events)
 	{
-		DBG1(DBG_KNL, "unable to create RT event socket");
-		destroy(this);
-		return NULL;
-	}
-	addr.nl_groups = RTMGRP_IPV4_IFADDR | RTMGRP_IPV6_IFADDR |
-					 RTMGRP_IPV4_ROUTE | RTMGRP_IPV6_ROUTE | RTMGRP_LINK;
-	if (bind(this->socket_events, (struct sockaddr*)&addr, sizeof(addr)))
-	{
-		DBG1(DBG_KNL, "unable to bind RT event socket");
-		destroy(this);
-		return NULL;
-	}
+		struct sockaddr_nl addr;
+
+		memset(&addr, 0, sizeof(addr));
+		addr.nl_family = AF_NETLINK;
 
-	this->job = callback_job_create_with_prio((callback_job_cb_t)receive_events,
-										this, NULL, NULL, JOB_PRIO_CRITICAL);
-	lib->processor->queue_job(lib->processor, (job_t*)this->job);
+		/* create and bind RT socket for events (address/interface/route changes) */
+		this->socket_events = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
+		if (this->socket_events < 0)
+		{
+			DBG1(DBG_KNL, "unable to create RT event socket");
+			destroy(this);
+			return NULL;
+		}
+		addr.nl_groups = RTMGRP_IPV4_IFADDR | RTMGRP_IPV6_IFADDR |
+						 RTMGRP_IPV4_ROUTE | RTMGRP_IPV6_ROUTE | RTMGRP_LINK;
+		if (bind(this->socket_events, (struct sockaddr*)&addr, sizeof(addr)))
+		{
+			DBG1(DBG_KNL, "unable to bind RT event socket");
+			destroy(this);
+			return NULL;
+		}
+
+		lib->processor->queue_job(lib->processor,
+			(job_t*)callback_job_create_with_prio(
+					(callback_job_cb_t)receive_events, this, NULL,
+					(callback_job_cancel_t)return_false, JOB_PRIO_CRITICAL));
+	}
 
 	if (init_address_list(this) != SUCCESS)
 	{