[deliverable/linux.git] / net / batman-adv / gateway_client.c

/*
 * Copyright (C) 2009-2011 B.A.T.M.A.N. contributors:
 *
 * Marek Lindner
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA
 *
 */

#include "main.h"
#include "gateway_client.h"
#include "gateway_common.h"
#include "hard-interface.h"
#include "originator.h"
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/udp.h>
#include <linux/if_vlan.h>

static void gw_node_free_rcu(struct rcu_head *rcu)
{
	struct gw_node *gw_node;

	gw_node = container_of(rcu, struct gw_node, rcu);
	kfree(gw_node);
}

static void gw_node_free_ref(struct gw_node *gw_node)
{
	if (atomic_dec_and_test(&gw_node->refcount))
		call_rcu(&gw_node->rcu, gw_node_free_rcu);
}

static struct gw_node *gw_get_selected_gw_node(struct bat_priv *bat_priv)
{
	struct gw_node *gw_node;

	rcu_read_lock();
	gw_node = rcu_dereference(bat_priv->curr_gw);
	if (!gw_node)
		goto out;

	if (!atomic_inc_not_zero(&gw_node->refcount))
		gw_node = NULL;

out:
	rcu_read_unlock();
	return gw_node;
}

struct orig_node *gw_get_selected_orig(struct bat_priv *bat_priv)
{
	struct gw_node *gw_node;
	struct orig_node *orig_node = NULL;

	gw_node = gw_get_selected_gw_node(bat_priv);
	if (!gw_node)
		goto out;

	rcu_read_lock();
	orig_node = gw_node->orig_node;
	if (!orig_node)
		goto unlock;

	if (!atomic_inc_not_zero(&orig_node->refcount))
		orig_node = NULL;

unlock:
	rcu_read_unlock();
out:
	if (gw_node)
		gw_node_free_ref(gw_node);
	return orig_node;
}

static void gw_select(struct bat_priv *bat_priv, struct gw_node *new_gw_node)
{
	struct gw_node *curr_gw_node;

	spin_lock_bh(&bat_priv->gw_list_lock);

	if (new_gw_node && !atomic_inc_not_zero(&new_gw_node->refcount))
		new_gw_node = NULL;

	curr_gw_node = bat_priv->curr_gw;
	rcu_assign_pointer(bat_priv->curr_gw, new_gw_node);

	if (curr_gw_node)
		gw_node_free_ref(curr_gw_node);

	spin_unlock_bh(&bat_priv->gw_list_lock);
}

void gw_deselect(struct bat_priv *bat_priv)
{
	gw_select(bat_priv, NULL);
}

void gw_election(struct bat_priv *bat_priv)
{
	struct hlist_node *node;
	struct gw_node *gw_node, *curr_gw = NULL, *curr_gw_tmp = NULL;
	struct neigh_node *router;
	uint8_t max_tq = 0;
	uint32_t max_gw_factor = 0, tmp_gw_factor = 0;
	int down, up;

	/**
	 * The batman daemon checks here if we already passed a full originator
	 * cycle in order to make sure we don't choose the first gateway we
	 * hear about. This check is based on the daemon's uptime which we
	 * don't have.
	 **/
	if (atomic_read(&bat_priv->gw_mode) != GW_MODE_CLIENT)
		return;

	curr_gw = gw_get_selected_gw_node(bat_priv);
	if (curr_gw)
		goto out;

	rcu_read_lock();
	if (hlist_empty(&bat_priv->gw_list)) {
		bat_dbg(DBG_BATMAN, bat_priv,
			"Removing selected gateway - "
			"no gateway in range\n");
		gw_deselect(bat_priv);
		goto unlock;
	}

	hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw_list, list) {
		if (gw_node->deleted)
			continue;

		router = orig_node_get_router(gw_node->orig_node);
		if (!router)
			continue;

		switch (atomic_read(&bat_priv->gw_sel_class)) {
		case 1: /* fast connection */
			gw_bandwidth_to_kbit(gw_node->orig_node->gw_flags,
					     &down, &up);

			tmp_gw_factor = (router->tq_avg * router->tq_avg *
					 down * 100 * 100) /
					 (TQ_LOCAL_WINDOW_SIZE *
					 TQ_LOCAL_WINDOW_SIZE * 64);

			if ((tmp_gw_factor > max_gw_factor) ||
			    ((tmp_gw_factor == max_gw_factor) &&
			     (router->tq_avg > max_tq)))
				curr_gw_tmp = gw_node;
			break;

		default: /**
			  * 2:  stable connection (use best statistic)
			  * 3:  fast-switch (use best statistic but change as
			  *     soon as a better gateway appears)
			  * XX: late-switch (use best statistic but change as
			  *     soon as a better gateway appears which has
			  *     $routing_class more tq points)
			  **/
			if (router->tq_avg > max_tq)
				curr_gw_tmp = gw_node;
			break;
		}

		if (router->tq_avg > max_tq)
			max_tq = router->tq_avg;

		if (tmp_gw_factor > max_gw_factor)
			max_gw_factor = tmp_gw_factor;

		neigh_node_free_ref(router);
	}

	if (curr_gw != curr_gw_tmp) {
		router = orig_node_get_router(curr_gw_tmp->orig_node);
		if (!router)
			goto unlock;

		if ((curr_gw) && (!curr_gw_tmp))
			bat_dbg(DBG_BATMAN, bat_priv,
				"Removing selected gateway - "
				"no gateway in range\n");
		else if ((!curr_gw) && (curr_gw_tmp))
			bat_dbg(DBG_BATMAN, bat_priv,
				"Adding route to gateway %pM "
				"(gw_flags: %i, tq: %i)\n",
				curr_gw_tmp->orig_node->orig,
				curr_gw_tmp->orig_node->gw_flags,
				router->tq_avg);
		else
			bat_dbg(DBG_BATMAN, bat_priv,
				"Changing route to gateway %pM "
				"(gw_flags: %i, tq: %i)\n",
				curr_gw_tmp->orig_node->orig,
				curr_gw_tmp->orig_node->gw_flags,
				router->tq_avg);

		neigh_node_free_ref(router);
		gw_select(bat_priv, curr_gw_tmp);
	}

unlock:
	rcu_read_unlock();
out:
	if (curr_gw)
		gw_node_free_ref(curr_gw);
}

void gw_check_election(struct bat_priv *bat_priv, struct orig_node *orig_node)
{
	struct orig_node *curr_gw_orig;
	struct neigh_node *router_gw = NULL, *router_orig = NULL;
	uint8_t gw_tq_avg, orig_tq_avg;

	curr_gw_orig = gw_get_selected_orig(bat_priv);
	if (!curr_gw_orig)
		goto deselect;

	router_gw = orig_node_get_router(curr_gw_orig);
	if (!router_gw)
		goto deselect;

	/* this node already is the gateway */
	if (curr_gw_orig == orig_node)
		goto out;

	router_orig = orig_node_get_router(orig_node);
	if (!router_orig)
		goto out;

	gw_tq_avg = router_gw->tq_avg;
	orig_tq_avg = router_orig->tq_avg;

	/* the TQ value has to be better */
	if (orig_tq_avg < gw_tq_avg)
		goto out;

	/**
	 * if the routing class is greater than 3 the value tells us how much
	 * greater the TQ value of the new gateway must be
	 **/
	if ((atomic_read(&bat_priv->gw_sel_class) > 3) &&
	    (orig_tq_avg - gw_tq_avg < atomic_read(&bat_priv->gw_sel_class)))
		goto out;

	bat_dbg(DBG_BATMAN, bat_priv,
		"Restarting gateway selection: better gateway found (tq curr: "
		"%i, tq new: %i)\n",
		gw_tq_avg, orig_tq_avg);

deselect:
	gw_deselect(bat_priv);
out:
	if (curr_gw_orig)
		orig_node_free_ref(curr_gw_orig);
	if (router_gw)
		neigh_node_free_ref(router_gw);
	if (router_orig)
		neigh_node_free_ref(router_orig);

	return;
}

static void gw_node_add(struct bat_priv *bat_priv,
			struct orig_node *orig_node, uint8_t new_gwflags)
{
	struct gw_node *gw_node;
	int down, up;

	gw_node = kmalloc(sizeof(struct gw_node), GFP_ATOMIC);
	if (!gw_node)
		return;

	memset(gw_node, 0, sizeof(struct gw_node));
	INIT_HLIST_NODE(&gw_node->list);
	gw_node->orig_node = orig_node;
	atomic_set(&gw_node->refcount, 1);

	spin_lock_bh(&bat_priv->gw_list_lock);
	hlist_add_head_rcu(&gw_node->list, &bat_priv->gw_list);
	spin_unlock_bh(&bat_priv->gw_list_lock);

	gw_bandwidth_to_kbit(new_gwflags, &down, &up);
	bat_dbg(DBG_BATMAN, bat_priv,
		"Found new gateway %pM -> gw_class: %i - %i%s/%i%s\n",
		orig_node->orig, new_gwflags,
		(down > 2048 ? down / 1024 : down),
		(down > 2048 ? "MBit" : "KBit"),
		(up > 2048 ? up / 1024 : up),
		(up > 2048 ? "MBit" : "KBit"));
}

void gw_node_update(struct bat_priv *bat_priv,
		    struct orig_node *orig_node, uint8_t new_gwflags)
{
	struct hlist_node *node;
	struct gw_node *gw_node, *curr_gw;

	/**
	 * Note: We don't need a NULL check here, since curr_gw never gets
	 * dereferenced. If curr_gw is NULL we also should not exit as we may
	 * have this gateway in our list (duplication check!) even though we
	 * have no currently selected gateway.
	 */
	curr_gw = gw_get_selected_gw_node(bat_priv);

	rcu_read_lock();
	hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw_list, list) {
		if (gw_node->orig_node != orig_node)
			continue;

		bat_dbg(DBG_BATMAN, bat_priv,
			"Gateway class of originator %pM changed from "
			"%i to %i\n",
			orig_node->orig, gw_node->orig_node->gw_flags,
			new_gwflags);

		gw_node->deleted = 0;

		if (new_gwflags == 0) {
			gw_node->deleted = jiffies;
			bat_dbg(DBG_BATMAN, bat_priv,
				"Gateway %pM removed from gateway list\n",
				orig_node->orig);

			if (gw_node == curr_gw)
				goto deselect;
		}

		goto unlock;
	}

	if (new_gwflags == 0)
		goto unlock;

	gw_node_add(bat_priv, orig_node, new_gwflags);
	goto unlock;

deselect:
	gw_deselect(bat_priv);
unlock:
	rcu_read_unlock();

	if (curr_gw)
		gw_node_free_ref(curr_gw);
}

void gw_node_delete(struct bat_priv *bat_priv, struct orig_node *orig_node)
{
	return gw_node_update(bat_priv, orig_node, 0);
}

void gw_node_purge(struct bat_priv *bat_priv)
{
	struct gw_node *gw_node, *curr_gw;
	struct hlist_node *node, *node_tmp;
	unsigned long timeout = 2 * PURGE_TIMEOUT * HZ;
	char do_deselect = 0;

	curr_gw = gw_get_selected_gw_node(bat_priv);

	spin_lock_bh(&bat_priv->gw_list_lock);

	hlist_for_each_entry_safe(gw_node, node, node_tmp,
				  &bat_priv->gw_list, list) {
		if (((!gw_node->deleted) ||
		     (time_before(jiffies, gw_node->deleted + timeout))) &&
		    atomic_read(&bat_priv->mesh_state) == MESH_ACTIVE)
			continue;

		if (curr_gw == gw_node)
			do_deselect = 1;

		hlist_del_rcu(&gw_node->list);
		gw_node_free_ref(gw_node);
	}

	spin_unlock_bh(&bat_priv->gw_list_lock);

	/* gw_deselect() needs to acquire the gw_list_lock */
	if (do_deselect)
		gw_deselect(bat_priv);

	if (curr_gw)
		gw_node_free_ref(curr_gw);
}

/**
 * fails if orig_node has no router
 */
static int _write_buffer_text(struct bat_priv *bat_priv,
			      struct seq_file *seq, struct gw_node *gw_node)
{
	struct gw_node *curr_gw;
	struct neigh_node *router;
	int down, up, ret = -1;

	gw_bandwidth_to_kbit(gw_node->orig_node->gw_flags, &down, &up);

	router = orig_node_get_router(gw_node->orig_node);
	if (!router)
		goto out;

	curr_gw = gw_get_selected_gw_node(bat_priv);

	ret = seq_printf(seq, "%s %pM (%3i) %pM [%10s]: %3i - %i%s/%i%s\n",
			 (curr_gw == gw_node ? "=>" : "  "),
			 gw_node->orig_node->orig,
			 router->tq_avg, router->addr,
			 router->if_incoming->net_dev->name,
			 gw_node->orig_node->gw_flags,
			 (down > 2048 ? down / 1024 : down),
			 (down > 2048 ? "MBit" : "KBit"),
			 (up > 2048 ? up / 1024 : up),
			 (up > 2048 ? "MBit" : "KBit"));

	neigh_node_free_ref(router);
	if (curr_gw)
		gw_node_free_ref(curr_gw);
out:
	return ret;
}

int gw_client_seq_print_text(struct seq_file *seq, void *offset)
{
	struct net_device *net_dev = (struct net_device *)seq->private;
	struct bat_priv *bat_priv = netdev_priv(net_dev);
	struct hard_iface *primary_if;
	struct gw_node *gw_node;
	struct hlist_node *node;
	int gw_count = 0, ret = 0;

	primary_if = primary_if_get_selected(bat_priv);
	if (!primary_if) {
		ret = seq_printf(seq, "BATMAN mesh %s disabled - please "
				 "specify interfaces to enable it\n",
				 net_dev->name);
		goto out;
	}

	if (primary_if->if_status != IF_ACTIVE) {
		ret = seq_printf(seq, "BATMAN mesh %s disabled - "
				 "primary interface not active\n",
				 net_dev->name);
		goto out;
	}

	seq_printf(seq, "      %-12s (%s/%i) %17s [%10s]: gw_class ... "
		   "[B.A.T.M.A.N. adv %s%s, MainIF/MAC: %s/%pM (%s)]\n",
		   "Gateway", "#", TQ_MAX_VALUE, "Nexthop",
		   "outgoingIF", SOURCE_VERSION, REVISION_VERSION_STR,
		   primary_if->net_dev->name,
		   primary_if->net_dev->dev_addr, net_dev->name);

	rcu_read_lock();
	hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw_list, list) {
		if (gw_node->deleted)
			continue;

		/* fails if orig_node has no router */
		if (_write_buffer_text(bat_priv, seq, gw_node) < 0)
			continue;

		gw_count++;
	}
	rcu_read_unlock();

	if (gw_count == 0)
		seq_printf(seq, "No gateways in range ...\n");

out:
	if (primary_if)
		hardif_free_ref(primary_if);
	return ret;
}

int gw_is_target(struct bat_priv *bat_priv, struct sk_buff *skb)
{
	struct ethhdr *ethhdr;
	struct iphdr *iphdr;
	struct ipv6hdr *ipv6hdr;
	struct udphdr *udphdr;
	struct gw_node *curr_gw;
	unsigned int header_len = 0;

	if (atomic_read(&bat_priv->gw_mode) == GW_MODE_OFF)
		return 0;

	/* check for ethernet header */
	if (!pskb_may_pull(skb, header_len + ETH_HLEN))
		return 0;
	ethhdr = (struct ethhdr *)skb->data;
	header_len += ETH_HLEN;

	/* check for initial vlan header */
	if (ntohs(ethhdr->h_proto) == ETH_P_8021Q) {
		if (!pskb_may_pull(skb, header_len + VLAN_HLEN))
			return 0;
		ethhdr = (struct ethhdr *)(skb->data + VLAN_HLEN);
		header_len += VLAN_HLEN;
	}

	/* check for ip header */
	switch (ntohs(ethhdr->h_proto)) {
	case ETH_P_IP:
		if (!pskb_may_pull(skb, header_len + sizeof(struct iphdr)))
			return 0;
		iphdr = (struct iphdr *)(skb->data + header_len);
		header_len += iphdr->ihl * 4;

		/* check for udp header */
		if (iphdr->protocol != IPPROTO_UDP)
			return 0;

		break;
	case ETH_P_IPV6:
		if (!pskb_may_pull(skb, header_len + sizeof(struct ipv6hdr)))
			return 0;
		ipv6hdr = (struct ipv6hdr *)(skb->data + header_len);
		header_len += sizeof(struct ipv6hdr);

		/* check for udp header */
		if (ipv6hdr->nexthdr != IPPROTO_UDP)
			return 0;

		break;
	default:
		return 0;
	}

	if (!pskb_may_pull(skb, header_len + sizeof(struct udphdr)))
		return 0;
	udphdr = (struct udphdr *)(skb->data + header_len);
	header_len += sizeof(struct udphdr);

	/* check for bootp port */
	if ((ntohs(ethhdr->h_proto) == ETH_P_IP) &&
	     (ntohs(udphdr->dest) != 67))
		return 0;

	if ((ntohs(ethhdr->h_proto) == ETH_P_IPV6) &&
	    (ntohs(udphdr->dest) != 547))
		return 0;

	if (atomic_read(&bat_priv->gw_mode) == GW_MODE_SERVER)
		return -1;

	curr_gw = gw_get_selected_gw_node(bat_priv);
	if (!curr_gw)
		return 0;

	if (curr_gw)
		gw_node_free_ref(curr_gw);
	return 1;
}
Commit	Line	Data
c6c8fea2	1	/*
64afe353	2	* Copyright (C) 2009-2011 B.A.T.M.A.N. contributors:
c6c8fea2 SE	3	*
	4	* Marek Lindner
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of version 2 of the GNU General Public
	8	* License as published by the Free Software Foundation.
	9	*
	10	* This program is distributed in the hope that it will be useful, but
	11	* WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	* General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public License
	16	* along with this program; if not, write to the Free Software
	17	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
	18	* 02110-1301, USA
	19	*
	20	*/
	21
	22	#include "main.h"
	23	#include "gateway_client.h"
	24	#include "gateway_common.h"
	25	#include "hard-interface.h"
57f0c07c	26	#include "originator.h"
c6c8fea2 SE	27	#include <linux/ip.h>
	28	#include <linux/ipv6.h>
	29	#include <linux/udp.h>
	30	#include <linux/if_vlan.h>
	31
25b6d3c1	32	static void gw_node_free_rcu(struct rcu_head *rcu)
c6c8fea2 SE	33	{
	34	struct gw_node *gw_node;
	35
25b6d3c1	36	gw_node = container_of(rcu, struct gw_node, rcu);
c6c8fea2 SE	37	kfree(gw_node);
	38	}
	39
25b6d3c1	40	static void gw_node_free_ref(struct gw_node *gw_node)
c6c8fea2	41	{
25b6d3c1 ML	42	if (atomic_dec_and_test(&gw_node->refcount))
25b6d3c1 ML	43	call_rcu(&gw_node->rcu, gw_node_free_rcu);
c6c8fea2 SE	44	}
c6c8fea2 SE	45
c4aac1ab	46	static struct gw_node gw_get_selected_gw_node(struct bat_priv bat_priv)
c6c8fea2	47	{
c4aac1ab	48	struct gw_node *gw_node;
c6c8fea2	49
5d02b3cd	50	rcu_read_lock();
c4aac1ab ML	51	gw_node = rcu_dereference(bat_priv->curr_gw);
c4aac1ab ML	52	if (!gw_node)
7b36e8ee	53	goto out;
c6c8fea2	54
c4aac1ab ML	55	if (!atomic_inc_not_zero(&gw_node->refcount))
c4aac1ab ML	56	gw_node = NULL;
43c70ad5	57
5d02b3cd LL	58	out:
5d02b3cd LL	59	rcu_read_unlock();
c4aac1ab	60	return gw_node;
c6c8fea2 SE	61	}
c6c8fea2 SE	62
c4aac1ab	63	struct orig_node gw_get_selected_orig(struct bat_priv bat_priv)
c6c8fea2	64	{
5d02b3cd	65	struct gw_node *gw_node;
c4aac1ab	66	struct orig_node *orig_node = NULL;
c6c8fea2	67
c4aac1ab ML	68	gw_node = gw_get_selected_gw_node(bat_priv);
	69	if (!gw_node)
	70	goto out;
	71
	72	rcu_read_lock();
	73	orig_node = gw_node->orig_node;
	74	if (!orig_node)
	75	goto unlock;
	76
	77	if (!atomic_inc_not_zero(&orig_node->refcount))
	78	orig_node = NULL;
c6c8fea2	79
c4aac1ab ML	80	unlock:
	81	rcu_read_unlock();
	82	out:
c6c8fea2	83	if (gw_node)
25b6d3c1	84	gw_node_free_ref(gw_node);
c4aac1ab	85	return orig_node;
c6c8fea2 SE	86	}
c6c8fea2 SE	87
25b6d3c1	88	static void gw_select(struct bat_priv bat_priv, struct gw_node new_gw_node)
c6c8fea2	89	{
5d02b3cd	90	struct gw_node *curr_gw_node;
c6c8fea2	91
c4aac1ab ML	92	spin_lock_bh(&bat_priv->gw_list_lock);
c4aac1ab ML	93
25b6d3c1 ML	94	if (new_gw_node && !atomic_inc_not_zero(&new_gw_node->refcount))
25b6d3c1 ML	95	new_gw_node = NULL;
c6c8fea2	96
c4aac1ab	97	curr_gw_node = bat_priv->curr_gw;
5d02b3cd	98	rcu_assign_pointer(bat_priv->curr_gw, new_gw_node);
25b6d3c1 ML	99
	100	if (curr_gw_node)
	101	gw_node_free_ref(curr_gw_node);
c4aac1ab ML	102
	103	spin_unlock_bh(&bat_priv->gw_list_lock);
	104	}
	105
	106	void gw_deselect(struct bat_priv *bat_priv)
	107	{
	108	gw_select(bat_priv, NULL);
c6c8fea2 SE	109	}
	110
	111	void gw_election(struct bat_priv *bat_priv)
	112	{
	113	struct hlist_node *node;
c4aac1ab	114	struct gw_node gw_node, curr_gw = NULL, *curr_gw_tmp = NULL;
e1a5382f	115	struct neigh_node *router;
c6c8fea2 SE	116	uint8_t max_tq = 0;
	117	uint32_t max_gw_factor = 0, tmp_gw_factor = 0;
	118	int down, up;
	119
	120	/**
	121	* The batman daemon checks here if we already passed a full originator
	122	* cycle in order to make sure we don't choose the first gateway we
	123	* hear about. This check is based on the daemon's uptime which we
	124	* don't have.
	125	**/
	126	if (atomic_read(&bat_priv->gw_mode) != GW_MODE_CLIENT)
	127	return;
	128
c4aac1ab	129	curr_gw = gw_get_selected_gw_node(bat_priv);
71e4aa9c	130	if (curr_gw)
c4aac1ab	131	goto out;
c6c8fea2	132
c4aac1ab	133	rcu_read_lock();
c6c8fea2	134	if (hlist_empty(&bat_priv->gw_list)) {
c4aac1ab ML	135	bat_dbg(DBG_BATMAN, bat_priv,
	136	"Removing selected gateway - "
	137	"no gateway in range\n");
	138	gw_deselect(bat_priv);
	139	goto unlock;
c6c8fea2 SE	140	}
	141
	142	hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw_list, list) {
e1a5382f	143	if (gw_node->deleted)
c6c8fea2 SE	144	continue;
c6c8fea2 SE	145
e1a5382f LL	146	router = orig_node_get_router(gw_node->orig_node);
e1a5382f LL	147	if (!router)
c6c8fea2 SE	148	continue;
	149
	150	switch (atomic_read(&bat_priv->gw_sel_class)) {
	151	case 1: /* fast connection */
	152	gw_bandwidth_to_kbit(gw_node->orig_node->gw_flags,
	153	&down, &up);
	154
e1a5382f	155	tmp_gw_factor = (router->tq_avg * router->tq_avg *
c6c8fea2 SE	156	down * 100 * 100) /
	157	(TQ_LOCAL_WINDOW_SIZE *
	158	TQ_LOCAL_WINDOW_SIZE * 64);
	159
	160	if ((tmp_gw_factor > max_gw_factor) \|\|
	161	((tmp_gw_factor == max_gw_factor) &&
e1a5382f	162	(router->tq_avg > max_tq)))
c6c8fea2 SE	163	curr_gw_tmp = gw_node;
	164	break;
	165
	166	default: /**
	167	* 2: stable connection (use best statistic)
	168	* 3: fast-switch (use best statistic but change as
	169	* soon as a better gateway appears)
	170	* XX: late-switch (use best statistic but change as
	171	* soon as a better gateway appears which has
	172	* $routing_class more tq points)
	173	**/
e1a5382f	174	if (router->tq_avg > max_tq)
c6c8fea2 SE	175	curr_gw_tmp = gw_node;
	176	break;
	177	}
	178
e1a5382f LL	179	if (router->tq_avg > max_tq)
e1a5382f LL	180	max_tq = router->tq_avg;
c6c8fea2 SE	181
	182	if (tmp_gw_factor > max_gw_factor)
	183	max_gw_factor = tmp_gw_factor;
e1a5382f LL	184
e1a5382f LL	185	neigh_node_free_ref(router);
c6c8fea2 SE	186	}
c6c8fea2 SE	187
5d02b3cd	188	if (curr_gw != curr_gw_tmp) {
e1a5382f LL	189	router = orig_node_get_router(curr_gw_tmp->orig_node);
e1a5382f LL	190	if (!router)
c4aac1ab	191	goto unlock;
e1a5382f	192
5d02b3cd	193	if ((curr_gw) && (!curr_gw_tmp))
c6c8fea2 SE	194	bat_dbg(DBG_BATMAN, bat_priv,
	195	"Removing selected gateway - "
	196	"no gateway in range\n");
5d02b3cd	197	else if ((!curr_gw) && (curr_gw_tmp))
c6c8fea2 SE	198	bat_dbg(DBG_BATMAN, bat_priv,
	199	"Adding route to gateway %pM "
	200	"(gw_flags: %i, tq: %i)\n",
	201	curr_gw_tmp->orig_node->orig,
	202	curr_gw_tmp->orig_node->gw_flags,
e1a5382f	203	router->tq_avg);
c6c8fea2 SE	204	else
	205	bat_dbg(DBG_BATMAN, bat_priv,
	206	"Changing route to gateway %pM "
	207	"(gw_flags: %i, tq: %i)\n",
	208	curr_gw_tmp->orig_node->orig,
	209	curr_gw_tmp->orig_node->gw_flags,
e1a5382f	210	router->tq_avg);
c6c8fea2	211
e1a5382f	212	neigh_node_free_ref(router);
25b6d3c1	213	gw_select(bat_priv, curr_gw_tmp);
c6c8fea2 SE	214	}
c6c8fea2 SE	215
c4aac1ab	216	unlock:
c6c8fea2	217	rcu_read_unlock();
c4aac1ab ML	218	out:
	219	if (curr_gw)
	220	gw_node_free_ref(curr_gw);
c6c8fea2 SE	221	}
	222
	223	void gw_check_election(struct bat_priv bat_priv, struct orig_node orig_node)
	224	{
57f0c07c	225	struct orig_node *curr_gw_orig;
e1a5382f	226	struct neigh_node router_gw = NULL, router_orig = NULL;
c6c8fea2 SE	227	uint8_t gw_tq_avg, orig_tq_avg;
c6c8fea2 SE	228
c4aac1ab	229	curr_gw_orig = gw_get_selected_orig(bat_priv);
57f0c07c LL	230	if (!curr_gw_orig)
57f0c07c LL	231	goto deselect;
c6c8fea2	232
e1a5382f LL	233	router_gw = orig_node_get_router(curr_gw_orig);
	234	if (!router_gw)
	235	goto deselect;
c6c8fea2 SE	236
c6c8fea2 SE	237	/* this node already is the gateway */
57f0c07c	238	if (curr_gw_orig == orig_node)
e1a5382f	239	goto out;
c6c8fea2	240
e1a5382f LL	241	router_orig = orig_node_get_router(orig_node);
	242	if (!router_orig)
	243	goto out;
5d02b3cd	244
e1a5382f LL	245	gw_tq_avg = router_gw->tq_avg;
e1a5382f LL	246	orig_tq_avg = router_orig->tq_avg;
c6c8fea2 SE	247
	248	/* the TQ value has to be better */
	249	if (orig_tq_avg < gw_tq_avg)
5d02b3cd	250	goto out;
c6c8fea2 SE	251
	252	/**
	253	* if the routing class is greater than 3 the value tells us how much
	254	* greater the TQ value of the new gateway must be
	255	**/
	256	if ((atomic_read(&bat_priv->gw_sel_class) > 3) &&
	257	(orig_tq_avg - gw_tq_avg < atomic_read(&bat_priv->gw_sel_class)))
5d02b3cd	258	goto out;
c6c8fea2 SE	259
	260	bat_dbg(DBG_BATMAN, bat_priv,
	261	"Restarting gateway selection: better gateway found (tq curr: "
	262	"%i, tq new: %i)\n",
	263	gw_tq_avg, orig_tq_avg);
	264
	265	deselect:
	266	gw_deselect(bat_priv);
5d02b3cd	267	out:
57f0c07c LL	268	if (curr_gw_orig)
57f0c07c LL	269	orig_node_free_ref(curr_gw_orig);
e1a5382f LL	270	if (router_gw)
	271	neigh_node_free_ref(router_gw);
	272	if (router_orig)
	273	neigh_node_free_ref(router_orig);
57f0c07c	274
5d02b3cd	275	return;
c6c8fea2 SE	276	}
	277
	278	static void gw_node_add(struct bat_priv *bat_priv,
	279	struct orig_node *orig_node, uint8_t new_gwflags)
	280	{
	281	struct gw_node *gw_node;
	282	int down, up;
	283
	284	gw_node = kmalloc(sizeof(struct gw_node), GFP_ATOMIC);
	285	if (!gw_node)
	286	return;
	287
	288	memset(gw_node, 0, sizeof(struct gw_node));
	289	INIT_HLIST_NODE(&gw_node->list);
	290	gw_node->orig_node = orig_node;
25b6d3c1	291	atomic_set(&gw_node->refcount, 1);
c6c8fea2 SE	292
	293	spin_lock_bh(&bat_priv->gw_list_lock);
	294	hlist_add_head_rcu(&gw_node->list, &bat_priv->gw_list);
	295	spin_unlock_bh(&bat_priv->gw_list_lock);
	296
	297	gw_bandwidth_to_kbit(new_gwflags, &down, &up);
	298	bat_dbg(DBG_BATMAN, bat_priv,
	299	"Found new gateway %pM -> gw_class: %i - %i%s/%i%s\n",
	300	orig_node->orig, new_gwflags,
	301	(down > 2048 ? down / 1024 : down),
	302	(down > 2048 ? "MBit" : "KBit"),
	303	(up > 2048 ? up / 1024 : up),
	304	(up > 2048 ? "MBit" : "KBit"));
	305	}
	306
	307	void gw_node_update(struct bat_priv *bat_priv,
	308	struct orig_node *orig_node, uint8_t new_gwflags)
	309	{
	310	struct hlist_node *node;
c4aac1ab ML	311	struct gw_node gw_node, curr_gw;
c4aac1ab ML	312
71e4aa9c AQ	313	/**
	314	* Note: We don't need a NULL check here, since curr_gw never gets
	315	* dereferenced. If curr_gw is NULL we also should not exit as we may
	316	* have this gateway in our list (duplication check!) even though we
	317	* have no currently selected gateway.
	318	*/
c4aac1ab	319	curr_gw = gw_get_selected_gw_node(bat_priv);
c6c8fea2 SE	320
	321	rcu_read_lock();
	322	hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw_list, list) {
	323	if (gw_node->orig_node != orig_node)
	324	continue;
	325
	326	bat_dbg(DBG_BATMAN, bat_priv,
	327	"Gateway class of originator %pM changed from "
	328	"%i to %i\n",
	329	orig_node->orig, gw_node->orig_node->gw_flags,
	330	new_gwflags);
	331
	332	gw_node->deleted = 0;
	333
	334	if (new_gwflags == 0) {
	335	gw_node->deleted = jiffies;
	336	bat_dbg(DBG_BATMAN, bat_priv,
	337	"Gateway %pM removed from gateway list\n",
	338	orig_node->orig);
	339
c4aac1ab ML	340	if (gw_node == curr_gw)
c4aac1ab ML	341	goto deselect;
c6c8fea2 SE	342	}
c6c8fea2 SE	343
c4aac1ab	344	goto unlock;
c6c8fea2	345	}
c6c8fea2 SE	346
c6c8fea2 SE	347	if (new_gwflags == 0)
c4aac1ab	348	goto unlock;
c6c8fea2 SE	349
c6c8fea2 SE	350	gw_node_add(bat_priv, orig_node, new_gwflags);
c4aac1ab ML	351	goto unlock;
	352
	353	deselect:
	354	gw_deselect(bat_priv);
	355	unlock:
	356	rcu_read_unlock();
71e4aa9c	357
c4aac1ab ML	358	if (curr_gw)
c4aac1ab ML	359	gw_node_free_ref(curr_gw);
c6c8fea2 SE	360	}
	361
	362	void gw_node_delete(struct bat_priv bat_priv, struct orig_node orig_node)
	363	{
	364	return gw_node_update(bat_priv, orig_node, 0);
	365	}
	366
	367	void gw_node_purge(struct bat_priv *bat_priv)
	368	{
c4aac1ab	369	struct gw_node gw_node, curr_gw;
c6c8fea2 SE	370	struct hlist_node node, node_tmp;
c6c8fea2 SE	371	unsigned long timeout = 2 * PURGE_TIMEOUT * HZ;
c4aac1ab ML	372	char do_deselect = 0;
	373
	374	curr_gw = gw_get_selected_gw_node(bat_priv);
c6c8fea2 SE	375
	376	spin_lock_bh(&bat_priv->gw_list_lock);
	377
	378	hlist_for_each_entry_safe(gw_node, node, node_tmp,
	379	&bat_priv->gw_list, list) {
	380	if (((!gw_node->deleted) \|\|
	381	(time_before(jiffies, gw_node->deleted + timeout))) &&
	382	atomic_read(&bat_priv->mesh_state) == MESH_ACTIVE)
	383	continue;
	384
c4aac1ab ML	385	if (curr_gw == gw_node)
c4aac1ab ML	386	do_deselect = 1;
c6c8fea2 SE	387
c6c8fea2 SE	388	hlist_del_rcu(&gw_node->list);
25b6d3c1	389	gw_node_free_ref(gw_node);
c6c8fea2 SE	390	}
c6c8fea2 SE	391
c6c8fea2	392	spin_unlock_bh(&bat_priv->gw_list_lock);
c4aac1ab ML	393
	394	/* gw_deselect() needs to acquire the gw_list_lock */
	395	if (do_deselect)
	396	gw_deselect(bat_priv);
	397
	398	if (curr_gw)
	399	gw_node_free_ref(curr_gw);
c6c8fea2 SE	400	}
c6c8fea2 SE	401
e1a5382f LL	402	/**
	403	* fails if orig_node has no router
	404	*/
c6c8fea2 SE	405	static int _write_buffer_text(struct bat_priv *bat_priv,
	406	struct seq_file seq, struct gw_node gw_node)
	407	{
5d02b3cd	408	struct gw_node *curr_gw;
e1a5382f LL	409	struct neigh_node *router;
e1a5382f LL	410	int down, up, ret = -1;
c6c8fea2 SE	411
	412	gw_bandwidth_to_kbit(gw_node->orig_node->gw_flags, &down, &up);
	413
e1a5382f LL	414	router = orig_node_get_router(gw_node->orig_node);
	415	if (!router)
	416	goto out;
	417
c4aac1ab	418	curr_gw = gw_get_selected_gw_node(bat_priv);
5d02b3cd LL	419
5d02b3cd LL	420	ret = seq_printf(seq, "%s %pM (%3i) %pM [%10s]: %3i - %i%s/%i%s\n",
c4aac1ab ML	421	(curr_gw == gw_node ? "=>" : " "),
	422	gw_node->orig_node->orig,
	423	router->tq_avg, router->addr,
	424	router->if_incoming->net_dev->name,
	425	gw_node->orig_node->gw_flags,
	426	(down > 2048 ? down / 1024 : down),
	427	(down > 2048 ? "MBit" : "KBit"),
	428	(up > 2048 ? up / 1024 : up),
	429	(up > 2048 ? "MBit" : "KBit"));
5d02b3cd	430
e1a5382f	431	neigh_node_free_ref(router);
c4aac1ab ML	432	if (curr_gw)
c4aac1ab ML	433	gw_node_free_ref(curr_gw);
e1a5382f	434	out:
5d02b3cd	435	return ret;
c6c8fea2 SE	436	}
	437
	438	int gw_client_seq_print_text(struct seq_file seq, void offset)
	439	{
	440	struct net_device net_dev = (struct net_device )seq->private;
	441	struct bat_priv *bat_priv = netdev_priv(net_dev);
32ae9b22	442	struct hard_iface *primary_if;
c6c8fea2 SE	443	struct gw_node *gw_node;
c6c8fea2 SE	444	struct hlist_node *node;
32ae9b22	445	int gw_count = 0, ret = 0;
c6c8fea2	446
32ae9b22 ML	447	primary_if = primary_if_get_selected(bat_priv);
	448	if (!primary_if) {
	449	ret = seq_printf(seq, "BATMAN mesh %s disabled - please "
	450	"specify interfaces to enable it\n",
	451	net_dev->name);
	452	goto out;
c6c8fea2 SE	453	}
c6c8fea2 SE	454
32ae9b22 ML	455	if (primary_if->if_status != IF_ACTIVE) {
	456	ret = seq_printf(seq, "BATMAN mesh %s disabled - "
	457	"primary interface not active\n",
	458	net_dev->name);
	459	goto out;
c6c8fea2 SE	460	}
	461
	462	seq_printf(seq, " %-12s (%s/%i) %17s [%10s]: gw_class ... "
	463	"[B.A.T.M.A.N. adv %s%s, MainIF/MAC: %s/%pM (%s)]\n",
	464	"Gateway", "#", TQ_MAX_VALUE, "Nexthop",
	465	"outgoingIF", SOURCE_VERSION, REVISION_VERSION_STR,
32ae9b22 ML	466	primary_if->net_dev->name,
32ae9b22 ML	467	primary_if->net_dev->dev_addr, net_dev->name);
c6c8fea2 SE	468
	469	rcu_read_lock();
	470	hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw_list, list) {
	471	if (gw_node->deleted)
	472	continue;
	473
e1a5382f LL	474	/* fails if orig_node has no router */
e1a5382f LL	475	if (_write_buffer_text(bat_priv, seq, gw_node) < 0)
c6c8fea2 SE	476	continue;
c6c8fea2 SE	477
c6c8fea2 SE	478	gw_count++;
	479	}
	480	rcu_read_unlock();
	481
	482	if (gw_count == 0)
	483	seq_printf(seq, "No gateways in range ...\n");
	484
32ae9b22 ML	485	out:
	486	if (primary_if)
	487	hardif_free_ref(primary_if);
	488	return ret;
c6c8fea2 SE	489	}
	490
	491	int gw_is_target(struct bat_priv bat_priv, struct sk_buff skb)
	492	{
	493	struct ethhdr *ethhdr;
	494	struct iphdr *iphdr;
	495	struct ipv6hdr *ipv6hdr;
	496	struct udphdr *udphdr;
c4aac1ab	497	struct gw_node *curr_gw;
c6c8fea2 SE	498	unsigned int header_len = 0;
	499
	500	if (atomic_read(&bat_priv->gw_mode) == GW_MODE_OFF)
	501	return 0;
	502
	503	/* check for ethernet header */
	504	if (!pskb_may_pull(skb, header_len + ETH_HLEN))
	505	return 0;
	506	ethhdr = (struct ethhdr *)skb->data;
	507	header_len += ETH_HLEN;
	508
	509	/* check for initial vlan header */
	510	if (ntohs(ethhdr->h_proto) == ETH_P_8021Q) {
	511	if (!pskb_may_pull(skb, header_len + VLAN_HLEN))
	512	return 0;
	513	ethhdr = (struct ethhdr *)(skb->data + VLAN_HLEN);
	514	header_len += VLAN_HLEN;
	515	}
	516
	517	/* check for ip header */
	518	switch (ntohs(ethhdr->h_proto)) {
	519	case ETH_P_IP:
	520	if (!pskb_may_pull(skb, header_len + sizeof(struct iphdr)))
	521	return 0;
	522	iphdr = (struct iphdr *)(skb->data + header_len);
	523	header_len += iphdr->ihl * 4;
	524
	525	/* check for udp header */
	526	if (iphdr->protocol != IPPROTO_UDP)
	527	return 0;
	528
	529	break;
	530	case ETH_P_IPV6:
	531	if (!pskb_may_pull(skb, header_len + sizeof(struct ipv6hdr)))
	532	return 0;
	533	ipv6hdr = (struct ipv6hdr *)(skb->data + header_len);
	534	header_len += sizeof(struct ipv6hdr);
	535
	536	/* check for udp header */
	537	if (ipv6hdr->nexthdr != IPPROTO_UDP)
	538	return 0;
	539
	540	break;
	541	default:
	542	return 0;
	543	}
	544
	545	if (!pskb_may_pull(skb, header_len + sizeof(struct udphdr)))
	546	return 0;
	547	udphdr = (struct udphdr *)(skb->data + header_len);
	548	header_len += sizeof(struct udphdr);
	549
	550	/* check for bootp port */
	551	if ((ntohs(ethhdr->h_proto) == ETH_P_IP) &&
	552	(ntohs(udphdr->dest) != 67))
	553	return 0;
	554
	555	if ((ntohs(ethhdr->h_proto) == ETH_P_IPV6) &&
	556	(ntohs(udphdr->dest) != 547))
	557	return 0;
	558
	559	if (atomic_read(&bat_priv->gw_mode) == GW_MODE_SERVER)
	560	return -1;
	561
c4aac1ab ML	562	curr_gw = gw_get_selected_gw_node(bat_priv);
c4aac1ab ML	563	if (!curr_gw)
c6c8fea2 SE	564	return 0;
c6c8fea2 SE	565
c4aac1ab ML	566	if (curr_gw)
c4aac1ab ML	567	gw_node_free_ref(curr_gw);
c6c8fea2 SE	568	return 1;
c6c8fea2 SE	569	}