[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 <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/udp.h>
#include <linux/if_vlan.h>

static void gw_node_free_ref(struct kref *refcount)
{
	struct gw_node *gw_node;

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

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

	gw_node = container_of(rcu, struct gw_node, rcu);
	kref_put(&gw_node->refcount, gw_node_free_ref);
}

void *gw_get_selected(struct bat_priv *bat_priv)
{
	struct gw_node *curr_gateway_tmp = bat_priv->curr_gw;

	if (!curr_gateway_tmp)
		return NULL;

	return curr_gateway_tmp->orig_node;
}

void gw_deselect(struct bat_priv *bat_priv)
{
	struct gw_node *gw_node = bat_priv->curr_gw;

	bat_priv->curr_gw = NULL;

	if (gw_node)
		kref_put(&gw_node->refcount, gw_node_free_ref);
}

static struct gw_node *gw_select(struct bat_priv *bat_priv,
			  struct gw_node *new_gw_node)
{
	struct gw_node *curr_gw_node = bat_priv->curr_gw;

	if (new_gw_node)
		kref_get(&new_gw_node->refcount);

	bat_priv->curr_gw = new_gw_node;
	return curr_gw_node;
}

void gw_election(struct bat_priv *bat_priv)
{
	struct hlist_node *node;
	struct gw_node *gw_node, *curr_gw_tmp = NULL, *old_gw_node = NULL;
	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;

	if (bat_priv->curr_gw)
		return;

	rcu_read_lock();
	if (hlist_empty(&bat_priv->gw_list)) {
		rcu_read_unlock();

		if (bat_priv->curr_gw) {
			bat_dbg(DBG_BATMAN, bat_priv,
				"Removing selected gateway - "
				"no gateway in range\n");
			gw_deselect(bat_priv);
		}

		return;
	}

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

		if (gw_node->deleted)
			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 = (gw_node->orig_node->router->tq_avg *
					 gw_node->orig_node->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) &&
			     (gw_node->orig_node->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 (gw_node->orig_node->router->tq_avg > max_tq)
				curr_gw_tmp = gw_node;
			break;
		}

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

		if (tmp_gw_factor > max_gw_factor)
			max_gw_factor = tmp_gw_factor;
	}

	if (bat_priv->curr_gw != curr_gw_tmp) {
		if ((bat_priv->curr_gw) && (!curr_gw_tmp))
			bat_dbg(DBG_BATMAN, bat_priv,
				"Removing selected gateway - "
				"no gateway in range\n");
		else if ((!bat_priv->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,
				curr_gw_tmp->orig_node->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,
				curr_gw_tmp->orig_node->router->tq_avg);

		old_gw_node = gw_select(bat_priv, curr_gw_tmp);
	}

	rcu_read_unlock();

	/* the kfree() has to be outside of the rcu lock */
	if (old_gw_node)
		kref_put(&old_gw_node->refcount, gw_node_free_ref);
}

void gw_check_election(struct bat_priv *bat_priv, struct orig_node *orig_node)
{
	struct gw_node *curr_gateway_tmp = bat_priv->curr_gw;
	uint8_t gw_tq_avg, orig_tq_avg;

	if (!curr_gateway_tmp)
		return;

	if (!curr_gateway_tmp->orig_node)
		goto deselect;

	if (!curr_gateway_tmp->orig_node->router)
		goto deselect;

	/* this node already is the gateway */
	if (curr_gateway_tmp->orig_node == orig_node)
		return;

	if (!orig_node->router)
		return;

	gw_tq_avg = curr_gateway_tmp->orig_node->router->tq_avg;
	orig_tq_avg = orig_node->router->tq_avg;

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

	/**
	 * 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)))
		return;

	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);
}

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;
	kref_init(&gw_node->refcount);

	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;

	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 == bat_priv->curr_gw) {
				rcu_read_unlock();
				gw_deselect(bat_priv);
				return;
			}
		}

		rcu_read_unlock();
		return;
	}
	rcu_read_unlock();

	if (new_gwflags == 0)
		return;

	gw_node_add(bat_priv, orig_node, new_gwflags);
}

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;
	struct hlist_node *node, *node_tmp;
	unsigned long timeout = 2 * PURGE_TIMEOUT * HZ;

	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 (bat_priv->curr_gw == gw_node)
			gw_deselect(bat_priv);

		hlist_del_rcu(&gw_node->list);
		call_rcu(&gw_node->rcu, gw_node_free_rcu);
	}


	spin_unlock_bh(&bat_priv->gw_list_lock);
}

static int _write_buffer_text(struct bat_priv *bat_priv,
			      struct seq_file *seq, struct gw_node *gw_node)
{
	int down, up;

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

	return seq_printf(seq, "%s %pM (%3i) %pM [%10s]: %3i - %i%s/%i%s\n",
		       (bat_priv->curr_gw == gw_node ? "=>" : "  "),
		       gw_node->orig_node->orig,
		       gw_node->orig_node->router->tq_avg,
		       gw_node->orig_node->router->addr,
		       gw_node->orig_node->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"));
}

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 gw_node *gw_node;
	struct hlist_node *node;
	int gw_count = 0;

	if (!bat_priv->primary_if) {

		return seq_printf(seq, "BATMAN mesh %s disabled - please "
				  "specify interfaces to enable it\n",
				  net_dev->name);
	}

	if (bat_priv->primary_if->if_status != IF_ACTIVE) {

		return seq_printf(seq, "BATMAN mesh %s disabled - "
				       "primary interface not active\n",
				       net_dev->name);
	}

	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,
		   bat_priv->primary_if->net_dev->name,
		   bat_priv->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;

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

		_write_buffer_text(bat_priv, seq, gw_node);
		gw_count++;
	}
	rcu_read_unlock();

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

	return 0;
}

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;
	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;

	if (!bat_priv->curr_gw)
		return 0;

	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"
	26	#include <linux/ip.h>
	27	#include <linux/ipv6.h>
	28	#include <linux/udp.h>
	29	#include <linux/if_vlan.h>
	30
	31	static void gw_node_free_ref(struct kref *refcount)
	32	{
	33	struct gw_node *gw_node;
	34
	35	gw_node = container_of(refcount, struct gw_node, refcount);
	36	kfree(gw_node);
	37	}
	38
	39	static void gw_node_free_rcu(struct rcu_head *rcu)
	40	{
	41	struct gw_node *gw_node;
	42
	43	gw_node = container_of(rcu, struct gw_node, rcu);
	44	kref_put(&gw_node->refcount, gw_node_free_ref);
	45	}
	46
	47	void gw_get_selected(struct bat_priv bat_priv)
	48	{
	49	struct gw_node *curr_gateway_tmp = bat_priv->curr_gw;
	50
	51	if (!curr_gateway_tmp)
	52	return NULL;
	53
	54	return curr_gateway_tmp->orig_node;
	55	}
	56
	57	void gw_deselect(struct bat_priv *bat_priv)
	58	{
	59	struct gw_node *gw_node = bat_priv->curr_gw;
	60
	61	bat_priv->curr_gw = NULL;
	62
	63	if (gw_node)
	64	kref_put(&gw_node->refcount, gw_node_free_ref);
	65	}
	66
67	static struct gw_node gw_select(struct bat_priv bat_priv,
68	struct gw_node *new_gw_node)
69	{
70	struct gw_node *curr_gw_node = bat_priv->curr_gw;
71
72	if (new_gw_node)
73	kref_get(&new_gw_node->refcount);
74
75	bat_priv->curr_gw = new_gw_node;
76	return curr_gw_node;
77	}
78
79	void gw_election(struct bat_priv *bat_priv)
80	{
81	struct hlist_node *node;
82	struct gw_node gw_node, curr_gw_tmp = NULL, *old_gw_node = NULL;
83	uint8_t max_tq = 0;
84	uint32_t max_gw_factor = 0, tmp_gw_factor = 0;
85	int down, up;
86
87	/**
88	* The batman daemon checks here if we already passed a full originator
89	* cycle in order to make sure we don't choose the first gateway we
90	* hear about. This check is based on the daemon's uptime which we
91	* don't have.
92	**/
93	if (atomic_read(&bat_priv->gw_mode) != GW_MODE_CLIENT)
94	return;
95
96	if (bat_priv->curr_gw)
97	return;
98
99	rcu_read_lock();
100	if (hlist_empty(&bat_priv->gw_list)) {
101	rcu_read_unlock();
102
103	if (bat_priv->curr_gw) {
104	bat_dbg(DBG_BATMAN, bat_priv,
105	"Removing selected gateway - "
106	"no gateway in range\n");
107	gw_deselect(bat_priv);
108	}
109
110	return;
111	}
112
113	hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw_list, list) {
114	if (!gw_node->orig_node->router)
115	continue;
116
117	if (gw_node->deleted)
118	continue;
119
120	switch (atomic_read(&bat_priv->gw_sel_class)) {
121	case 1: /* fast connection */
122	gw_bandwidth_to_kbit(gw_node->orig_node->gw_flags,
123	&down, &up);
124
125	tmp_gw_factor = (gw_node->orig_node->router->tq_avg *
126	gw_node->orig_node->router->tq_avg *
127	down * 100 * 100) /
128	(TQ_LOCAL_WINDOW_SIZE *
129	TQ_LOCAL_WINDOW_SIZE * 64);
130
131	if ((tmp_gw_factor > max_gw_factor) \|\|
132	((tmp_gw_factor == max_gw_factor) &&
133	(gw_node->orig_node->router->tq_avg > max_tq)))
134	curr_gw_tmp = gw_node;
135	break;
136
137	default: /**
138	* 2: stable connection (use best statistic)
139	* 3: fast-switch (use best statistic but change as
140	* soon as a better gateway appears)
141	* XX: late-switch (use best statistic but change as
142	* soon as a better gateway appears which has
143	* $routing_class more tq points)
144	**/
145	if (gw_node->orig_node->router->tq_avg > max_tq)
146	curr_gw_tmp = gw_node;
147	break;
148	}
149
150	if (gw_node->orig_node->router->tq_avg > max_tq)
151	max_tq = gw_node->orig_node->router->tq_avg;
152
153	if (tmp_gw_factor > max_gw_factor)
154	max_gw_factor = tmp_gw_factor;
155	}
156
157	if (bat_priv->curr_gw != curr_gw_tmp) {
158	if ((bat_priv->curr_gw) && (!curr_gw_tmp))
159	bat_dbg(DBG_BATMAN, bat_priv,
160	"Removing selected gateway - "
161	"no gateway in range\n");
162	else if ((!bat_priv->curr_gw) && (curr_gw_tmp))
163	bat_dbg(DBG_BATMAN, bat_priv,
164	"Adding route to gateway %pM "
165	"(gw_flags: %i, tq: %i)\n",
166	curr_gw_tmp->orig_node->orig,
167	curr_gw_tmp->orig_node->gw_flags,
168	curr_gw_tmp->orig_node->router->tq_avg);
169	else
170	bat_dbg(DBG_BATMAN, bat_priv,
171	"Changing route to gateway %pM "
172	"(gw_flags: %i, tq: %i)\n",
173	curr_gw_tmp->orig_node->orig,
174	curr_gw_tmp->orig_node->gw_flags,
175	curr_gw_tmp->orig_node->router->tq_avg);
176
177	old_gw_node = gw_select(bat_priv, curr_gw_tmp);
178	}
179
180	rcu_read_unlock();
181
182	/* the kfree() has to be outside of the rcu lock */
183	if (old_gw_node)
184	kref_put(&old_gw_node->refcount, gw_node_free_ref);
185	}
186
187	void gw_check_election(struct bat_priv bat_priv, struct orig_node orig_node)
188	{
189	struct gw_node *curr_gateway_tmp = bat_priv->curr_gw;
190	uint8_t gw_tq_avg, orig_tq_avg;
191
192	if (!curr_gateway_tmp)
193	return;
194
195	if (!curr_gateway_tmp->orig_node)
196	goto deselect;
197
198	if (!curr_gateway_tmp->orig_node->router)
199	goto deselect;
200
201	/* this node already is the gateway */
202	if (curr_gateway_tmp->orig_node == orig_node)
203	return;
204
205	if (!orig_node->router)
206	return;
207
208	gw_tq_avg = curr_gateway_tmp->orig_node->router->tq_avg;
209	orig_tq_avg = orig_node->router->tq_avg;
210
211	/* the TQ value has to be better */
212	if (orig_tq_avg < gw_tq_avg)
213	return;
214
215	/**
216	* if the routing class is greater than 3 the value tells us how much
217	* greater the TQ value of the new gateway must be
218	**/
219	if ((atomic_read(&bat_priv->gw_sel_class) > 3) &&
220	(orig_tq_avg - gw_tq_avg < atomic_read(&bat_priv->gw_sel_class)))
221	return;
222
223	bat_dbg(DBG_BATMAN, bat_priv,
224	"Restarting gateway selection: better gateway found (tq curr: "
225	"%i, tq new: %i)\n",
226	gw_tq_avg, orig_tq_avg);
227
228	deselect:
229	gw_deselect(bat_priv);
230	}
231
232	static void gw_node_add(struct bat_priv *bat_priv,
233	struct orig_node *orig_node, uint8_t new_gwflags)
234	{
235	struct gw_node *gw_node;
236	int down, up;
237
238	gw_node = kmalloc(sizeof(struct gw_node), GFP_ATOMIC);
239	if (!gw_node)
240	return;
241
242	memset(gw_node, 0, sizeof(struct gw_node));
243	INIT_HLIST_NODE(&gw_node->list);
244	gw_node->orig_node = orig_node;
245	kref_init(&gw_node->refcount);
246
247	spin_lock_bh(&bat_priv->gw_list_lock);
248	hlist_add_head_rcu(&gw_node->list, &bat_priv->gw_list);
249	spin_unlock_bh(&bat_priv->gw_list_lock);
250
251	gw_bandwidth_to_kbit(new_gwflags, &down, &up);
252	bat_dbg(DBG_BATMAN, bat_priv,
253	"Found new gateway %pM -> gw_class: %i - %i%s/%i%s\n",
254	orig_node->orig, new_gwflags,
255	(down > 2048 ? down / 1024 : down),
256	(down > 2048 ? "MBit" : "KBit"),
257	(up > 2048 ? up / 1024 : up),
258	(up > 2048 ? "MBit" : "KBit"));
259	}
260
261	void gw_node_update(struct bat_priv *bat_priv,
262	struct orig_node *orig_node, uint8_t new_gwflags)
263	{
264	struct hlist_node *node;
265	struct gw_node *gw_node;
266
267	rcu_read_lock();
268	hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw_list, list) {
269	if (gw_node->orig_node != orig_node)
270	continue;
271
272	bat_dbg(DBG_BATMAN, bat_priv,
273	"Gateway class of originator %pM changed from "
274	"%i to %i\n",
275	orig_node->orig, gw_node->orig_node->gw_flags,
276	new_gwflags);
277
278	gw_node->deleted = 0;
279
280	if (new_gwflags == 0) {
281	gw_node->deleted = jiffies;
282	bat_dbg(DBG_BATMAN, bat_priv,
283	"Gateway %pM removed from gateway list\n",
284	orig_node->orig);
285
286	if (gw_node == bat_priv->curr_gw) {
287	rcu_read_unlock();
288	gw_deselect(bat_priv);
289	return;
290	}
291	}
292
293	rcu_read_unlock();
294	return;
295	}
296	rcu_read_unlock();
297
298	if (new_gwflags == 0)
299	return;
300
301	gw_node_add(bat_priv, orig_node, new_gwflags);
302	}
303
304	void gw_node_delete(struct bat_priv bat_priv, struct orig_node orig_node)
305	{
306	return gw_node_update(bat_priv, orig_node, 0);
307	}
308
309	void gw_node_purge(struct bat_priv *bat_priv)
310	{
311	struct gw_node *gw_node;
312	struct hlist_node node, node_tmp;
313	unsigned long timeout = 2 * PURGE_TIMEOUT * HZ;
314
315	spin_lock_bh(&bat_priv->gw_list_lock);
316
317	hlist_for_each_entry_safe(gw_node, node, node_tmp,
318	&bat_priv->gw_list, list) {
319	if (((!gw_node->deleted) \|\|
320	(time_before(jiffies, gw_node->deleted + timeout))) &&
321	atomic_read(&bat_priv->mesh_state) == MESH_ACTIVE)
322	continue;
323
324	if (bat_priv->curr_gw == gw_node)
325	gw_deselect(bat_priv);
326
327	hlist_del_rcu(&gw_node->list);
328	call_rcu(&gw_node->rcu, gw_node_free_rcu);
329	}
330
331
332	spin_unlock_bh(&bat_priv->gw_list_lock);
333	}
334
335	static int _write_buffer_text(struct bat_priv *bat_priv,
336	struct seq_file seq, struct gw_node gw_node)
337	{
338	int down, up;
339
340	gw_bandwidth_to_kbit(gw_node->orig_node->gw_flags, &down, &up);
341
342	return seq_printf(seq, "%s %pM (%3i) %pM [%10s]: %3i - %i%s/%i%s\n",
343	(bat_priv->curr_gw == gw_node ? "=>" : " "),
344	gw_node->orig_node->orig,
345	gw_node->orig_node->router->tq_avg,
346	gw_node->orig_node->router->addr,
347	gw_node->orig_node->router->if_incoming->net_dev->name,
348	gw_node->orig_node->gw_flags,
349	(down > 2048 ? down / 1024 : down),
350	(down > 2048 ? "MBit" : "KBit"),
351	(up > 2048 ? up / 1024 : up),
352	(up > 2048 ? "MBit" : "KBit"));
353	}
354
355	int gw_client_seq_print_text(struct seq_file seq, void offset)
356	{
357	struct net_device net_dev = (struct net_device )seq->private;
358	struct bat_priv *bat_priv = netdev_priv(net_dev);
359	struct gw_node *gw_node;
360	struct hlist_node *node;
361	int gw_count = 0;
362
363	if (!bat_priv->primary_if) {
364
365	return seq_printf(seq, "BATMAN mesh %s disabled - please "
366	"specify interfaces to enable it\n",
367	net_dev->name);
368	}
369
370	if (bat_priv->primary_if->if_status != IF_ACTIVE) {
371
372	return seq_printf(seq, "BATMAN mesh %s disabled - "
373	"primary interface not active\n",
374	net_dev->name);
375	}
376
377	seq_printf(seq, " %-12s (%s/%i) %17s [%10s]: gw_class ... "
378	"[B.A.T.M.A.N. adv %s%s, MainIF/MAC: %s/%pM (%s)]\n",
379	"Gateway", "#", TQ_MAX_VALUE, "Nexthop",
380	"outgoingIF", SOURCE_VERSION, REVISION_VERSION_STR,
381	bat_priv->primary_if->net_dev->name,
382	bat_priv->primary_if->net_dev->dev_addr, net_dev->name);
383
384	rcu_read_lock();
385	hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw_list, list) {
386	if (gw_node->deleted)
387	continue;
388
389	if (!gw_node->orig_node->router)
390	continue;
391
392	_write_buffer_text(bat_priv, seq, gw_node);
393	gw_count++;
394	}
395	rcu_read_unlock();
396
397	if (gw_count == 0)
398	seq_printf(seq, "No gateways in range ...\n");
399
400	return 0;
401	}
402
403	int gw_is_target(struct bat_priv bat_priv, struct sk_buff skb)
404	{
405	struct ethhdr *ethhdr;
406	struct iphdr *iphdr;
407	struct ipv6hdr *ipv6hdr;
408	struct udphdr *udphdr;
409	unsigned int header_len = 0;
410
411	if (atomic_read(&bat_priv->gw_mode) == GW_MODE_OFF)
412	return 0;
413
414	/* check for ethernet header */
415	if (!pskb_may_pull(skb, header_len + ETH_HLEN))
416	return 0;
417	ethhdr = (struct ethhdr *)skb->data;
418	header_len += ETH_HLEN;
419
420	/* check for initial vlan header */
421	if (ntohs(ethhdr->h_proto) == ETH_P_8021Q) {
422	if (!pskb_may_pull(skb, header_len + VLAN_HLEN))
423	return 0;
424	ethhdr = (struct ethhdr *)(skb->data + VLAN_HLEN);
425	header_len += VLAN_HLEN;
426	}
427
428	/* check for ip header */
429	switch (ntohs(ethhdr->h_proto)) {
430	case ETH_P_IP:
431	if (!pskb_may_pull(skb, header_len + sizeof(struct iphdr)))
432	return 0;
433	iphdr = (struct iphdr *)(skb->data + header_len);
434	header_len += iphdr->ihl * 4;
435
436	/* check for udp header */
437	if (iphdr->protocol != IPPROTO_UDP)
438	return 0;
439
440	break;
441	case ETH_P_IPV6:
442	if (!pskb_may_pull(skb, header_len + sizeof(struct ipv6hdr)))
443	return 0;
444	ipv6hdr = (struct ipv6hdr *)(skb->data + header_len);
445	header_len += sizeof(struct ipv6hdr);
446
447	/* check for udp header */
448	if (ipv6hdr->nexthdr != IPPROTO_UDP)
449	return 0;
450
451	break;
452	default:
453	return 0;
454	}
455
456	if (!pskb_may_pull(skb, header_len + sizeof(struct udphdr)))
457	return 0;
458	udphdr = (struct udphdr *)(skb->data + header_len);
459	header_len += sizeof(struct udphdr);
460
461	/* check for bootp port */
462	if ((ntohs(ethhdr->h_proto) == ETH_P_IP) &&
463	(ntohs(udphdr->dest) != 67))
464	return 0;
465
466	if ((ntohs(ethhdr->h_proto) == ETH_P_IPV6) &&
467	(ntohs(udphdr->dest) != 547))
468	return 0;
469
470	if (atomic_read(&bat_priv->gw_mode) == GW_MODE_SERVER)
471	return -1;
472
473	if (!bat_priv->curr_gw)
474	return 0;
475
476	return 1;
477	}