blob: e0bcf9e842737427e8dc6d8f5e1be57f92252933 [file] [log] [blame]
Simon Wunderliche19f9752014-01-04 18:04:25 +01001/* Copyright (C) 2009-2014 B.A.T.M.A.N. contributors:
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +00002 *
3 * Marek Lindner
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of version 2 of the GNU General Public
7 * License as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
Antonio Quartulliebf38fb2013-11-03 20:40:48 +010015 * along with this program; if not, see <http://www.gnu.org/licenses/>.
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000016 */
17
18#include "main.h"
Sven Eckelmannb706b132012-06-10 23:58:51 +020019#include "sysfs.h"
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000020#include "gateway_client.h"
21#include "gateway_common.h"
22#include "hard-interface.h"
Linus Lüssing57f0c072011-03-14 22:43:33 +000023#include "originator.h"
Marek Lindnerbe7af5c2011-09-08 13:12:53 +020024#include "translation-table.h"
Antonio Quartulli43676ab52011-04-26 21:31:45 +020025#include "routing.h"
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000026#include <linux/ip.h>
27#include <linux/ipv6.h>
28#include <linux/udp.h>
29#include <linux/if_vlan.h>
30
Antonio Quartulli6c413b12013-11-05 19:31:08 +010031/* These are the offsets of the "hw type" and "hw address length" in the dhcp
32 * packet starting at the beginning of the dhcp header
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +020033 */
Antonio Quartulli6c413b12013-11-05 19:31:08 +010034#define BATADV_DHCP_HTYPE_OFFSET 1
35#define BATADV_DHCP_HLEN_OFFSET 2
36/* Value of htype representing Ethernet */
37#define BATADV_DHCP_HTYPE_ETHERNET 0x01
38/* This is the offset of the "chaddr" field in the dhcp packet starting at the
39 * beginning of the dhcp header
40 */
41#define BATADV_DHCP_CHADDR_OFFSET 28
Antonio Quartulli43676ab52011-04-26 21:31:45 +020042
Sven Eckelmann56303d32012-06-05 22:31:31 +020043static void batadv_gw_node_free_ref(struct batadv_gw_node *gw_node)
Marek Lindner25b6d3c2011-02-10 14:33:49 +000044{
Antonio Quartulli377fe0f2014-05-02 01:35:13 +020045 if (atomic_dec_and_test(&gw_node->refcount)) {
46 batadv_orig_node_free_ref(gw_node->orig_node);
Paul E. McKenneyeb340b22011-05-01 23:25:02 -070047 kfree_rcu(gw_node, rcu);
Antonio Quartulli377fe0f2014-05-02 01:35:13 +020048 }
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000049}
50
Sven Eckelmann56303d32012-06-05 22:31:31 +020051static struct batadv_gw_node *
52batadv_gw_get_selected_gw_node(struct batadv_priv *bat_priv)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000053{
Sven Eckelmann56303d32012-06-05 22:31:31 +020054 struct batadv_gw_node *gw_node;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000055
Linus Lüssing5d02b3c2011-02-13 21:13:02 +000056 rcu_read_lock();
Sven Eckelmann807736f2012-07-15 22:26:51 +020057 gw_node = rcu_dereference(bat_priv->gw.curr_gw);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010058 if (!gw_node)
Linus Lüssing5d02b3c2011-02-13 21:13:02 +000059 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000060
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010061 if (!atomic_inc_not_zero(&gw_node->refcount))
62 gw_node = NULL;
63
64out:
65 rcu_read_unlock();
66 return gw_node;
67}
68
Sven Eckelmann56303d32012-06-05 22:31:31 +020069struct batadv_orig_node *
70batadv_gw_get_selected_orig(struct batadv_priv *bat_priv)
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010071{
Sven Eckelmann56303d32012-06-05 22:31:31 +020072 struct batadv_gw_node *gw_node;
73 struct batadv_orig_node *orig_node = NULL;
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010074
Sven Eckelmann1409a832012-05-12 18:33:55 +020075 gw_node = batadv_gw_get_selected_gw_node(bat_priv);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010076 if (!gw_node)
Marek Lindner7b36e8e2011-02-18 12:28:10 +000077 goto out;
Linus Lüssing5d02b3c2011-02-13 21:13:02 +000078
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010079 rcu_read_lock();
80 orig_node = gw_node->orig_node;
81 if (!orig_node)
82 goto unlock;
83
Marek Lindner7b36e8e2011-02-18 12:28:10 +000084 if (!atomic_inc_not_zero(&orig_node->refcount))
85 orig_node = NULL;
Linus Lüssing43c70ad2011-02-13 21:13:04 +000086
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010087unlock:
Linus Lüssing5d02b3c2011-02-13 21:13:02 +000088 rcu_read_unlock();
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010089out:
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000090 if (gw_node)
Sven Eckelmann1409a832012-05-12 18:33:55 +020091 batadv_gw_node_free_ref(gw_node);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010092 return orig_node;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000093}
94
Sven Eckelmann56303d32012-06-05 22:31:31 +020095static void batadv_gw_select(struct batadv_priv *bat_priv,
96 struct batadv_gw_node *new_gw_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000097{
Sven Eckelmann56303d32012-06-05 22:31:31 +020098 struct batadv_gw_node *curr_gw_node;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000099
Sven Eckelmann807736f2012-07-15 22:26:51 +0200100 spin_lock_bh(&bat_priv->gw.list_lock);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100101
Marek Lindner25b6d3c2011-02-10 14:33:49 +0000102 if (new_gw_node && !atomic_inc_not_zero(&new_gw_node->refcount))
103 new_gw_node = NULL;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000104
Sven Eckelmann807736f2012-07-15 22:26:51 +0200105 curr_gw_node = rcu_dereference_protected(bat_priv->gw.curr_gw, 1);
106 rcu_assign_pointer(bat_priv->gw.curr_gw, new_gw_node);
Marek Lindner25b6d3c2011-02-10 14:33:49 +0000107
108 if (curr_gw_node)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200109 batadv_gw_node_free_ref(curr_gw_node);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100110
Sven Eckelmann807736f2012-07-15 22:26:51 +0200111 spin_unlock_bh(&bat_priv->gw.list_lock);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100112}
113
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100114/**
115 * batadv_gw_reselect - force a gateway reselection
116 * @bat_priv: the bat priv with all the soft interface information
117 *
118 * Set a flag to remind the GW component to perform a new gateway reselection.
119 * However this function does not ensure that the current gateway is going to be
120 * deselected. The reselection mechanism may elect the same gateway once again.
121 *
122 * This means that invoking batadv_gw_reselect() does not guarantee a gateway
123 * change and therefore a uevent is not necessarily expected.
124 */
125void batadv_gw_reselect(struct batadv_priv *bat_priv)
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100126{
Sven Eckelmann807736f2012-07-15 22:26:51 +0200127 atomic_set(&bat_priv->gw.reselect, 1);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000128}
129
Sven Eckelmann56303d32012-06-05 22:31:31 +0200130static struct batadv_gw_node *
131batadv_gw_get_best_gw_node(struct batadv_priv *bat_priv)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000132{
Sven Eckelmann56303d32012-06-05 22:31:31 +0200133 struct batadv_neigh_node *router;
Simon Wunderlich89652332013-11-13 19:14:46 +0100134 struct batadv_neigh_ifinfo *router_ifinfo;
Sven Eckelmann56303d32012-06-05 22:31:31 +0200135 struct batadv_gw_node *gw_node, *curr_gw = NULL;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000136 uint32_t max_gw_factor = 0, tmp_gw_factor = 0;
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200137 uint32_t gw_divisor;
Antonio Quartulli2265c142011-04-27 00:22:00 +0200138 uint8_t max_tq = 0;
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200139 uint8_t tq_avg;
Sven Eckelmann56303d32012-06-05 22:31:31 +0200140 struct batadv_orig_node *orig_node;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000141
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200142 gw_divisor = BATADV_TQ_LOCAL_WINDOW_SIZE * BATADV_TQ_LOCAL_WINDOW_SIZE;
143 gw_divisor *= 64;
144
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000145 rcu_read_lock();
Sasha Levinb67bfe02013-02-27 17:06:00 -0800146 hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000147 if (gw_node->deleted)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000148 continue;
149
Sven Eckelmann84d5e5e2012-05-12 02:09:30 +0200150 orig_node = gw_node->orig_node;
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100151 router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000152 if (!router)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000153 continue;
154
Simon Wunderlich89652332013-11-13 19:14:46 +0100155 router_ifinfo = batadv_neigh_ifinfo_get(router,
156 BATADV_IF_DEFAULT);
157 if (!router_ifinfo)
158 goto next;
159
Antonio Quartulli2265c142011-04-27 00:22:00 +0200160 if (!atomic_inc_not_zero(&gw_node->refcount))
161 goto next;
162
Simon Wunderlich89652332013-11-13 19:14:46 +0100163 tq_avg = router_ifinfo->bat_iv.tq_avg;
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200164
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000165 switch (atomic_read(&bat_priv->gw_sel_class)) {
166 case 1: /* fast connection */
Marek Lindner414254e2013-04-23 21:39:58 +0800167 tmp_gw_factor = tq_avg * tq_avg;
168 tmp_gw_factor *= gw_node->bandwidth_down;
169 tmp_gw_factor *= 100 * 100;
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200170 tmp_gw_factor /= gw_divisor;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000171
172 if ((tmp_gw_factor > max_gw_factor) ||
173 ((tmp_gw_factor == max_gw_factor) &&
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200174 (tq_avg > max_tq))) {
Antonio Quartulli2265c142011-04-27 00:22:00 +0200175 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200176 batadv_gw_node_free_ref(curr_gw);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200177 curr_gw = gw_node;
178 atomic_inc(&curr_gw->refcount);
179 }
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000180 break;
181
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200182 default: /* 2: stable connection (use best statistic)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000183 * 3: fast-switch (use best statistic but change as
184 * soon as a better gateway appears)
185 * XX: late-switch (use best statistic but change as
186 * soon as a better gateway appears which has
187 * $routing_class more tq points)
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200188 */
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200189 if (tq_avg > max_tq) {
Antonio Quartulli2265c142011-04-27 00:22:00 +0200190 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200191 batadv_gw_node_free_ref(curr_gw);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200192 curr_gw = gw_node;
193 atomic_inc(&curr_gw->refcount);
194 }
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000195 break;
196 }
197
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200198 if (tq_avg > max_tq)
199 max_tq = tq_avg;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000200
201 if (tmp_gw_factor > max_gw_factor)
202 max_gw_factor = tmp_gw_factor;
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000203
Sven Eckelmann1409a832012-05-12 18:33:55 +0200204 batadv_gw_node_free_ref(gw_node);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200205
206next:
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200207 batadv_neigh_node_free_ref(router);
Simon Wunderlich89652332013-11-13 19:14:46 +0100208 if (router_ifinfo)
209 batadv_neigh_ifinfo_free_ref(router_ifinfo);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000210 }
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000211 rcu_read_unlock();
Antonio Quartulli2265c142011-04-27 00:22:00 +0200212
213 return curr_gw;
214}
215
Antonio Quartullic6eaa3f2013-07-13 00:06:00 +0200216/**
217 * batadv_gw_check_client_stop - check if client mode has been switched off
218 * @bat_priv: the bat priv with all the soft interface information
219 *
220 * This function assumes the caller has checked that the gw state *is actually
221 * changing*. This function is not supposed to be called when there is no state
222 * change.
223 */
224void batadv_gw_check_client_stop(struct batadv_priv *bat_priv)
225{
226 struct batadv_gw_node *curr_gw;
227
228 if (atomic_read(&bat_priv->gw_mode) != BATADV_GW_MODE_CLIENT)
229 return;
230
231 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
232 if (!curr_gw)
233 return;
234
Antonio Quartullif3163182013-11-04 20:59:40 +0100235 /* deselect the current gateway so that next time that client mode is
236 * enabled a proper GW_ADD event can be sent
237 */
238 batadv_gw_select(bat_priv, NULL);
239
Antonio Quartullic6eaa3f2013-07-13 00:06:00 +0200240 /* if batman-adv is switching the gw client mode off and a gateway was
241 * already selected, send a DEL uevent
242 */
243 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_DEL, NULL);
244
245 batadv_gw_node_free_ref(curr_gw);
246}
247
Sven Eckelmann56303d32012-06-05 22:31:31 +0200248void batadv_gw_election(struct batadv_priv *bat_priv)
Antonio Quartulli2265c142011-04-27 00:22:00 +0200249{
Sven Eckelmann56303d32012-06-05 22:31:31 +0200250 struct batadv_gw_node *curr_gw = NULL, *next_gw = NULL;
251 struct batadv_neigh_node *router = NULL;
Simon Wunderlich89652332013-11-13 19:14:46 +0100252 struct batadv_neigh_ifinfo *router_ifinfo = NULL;
Antonio Quartulli19595e02011-06-12 11:58:58 +0200253 char gw_addr[18] = { '\0' };
Antonio Quartulli2265c142011-04-27 00:22:00 +0200254
Sven Eckelmanncd646ab2012-06-03 22:19:18 +0200255 if (atomic_read(&bat_priv->gw_mode) != BATADV_GW_MODE_CLIENT)
Antonio Quartulli2265c142011-04-27 00:22:00 +0200256 goto out;
257
Sven Eckelmann1409a832012-05-12 18:33:55 +0200258 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200259
Sven Eckelmann807736f2012-07-15 22:26:51 +0200260 if (!batadv_atomic_dec_not_zero(&bat_priv->gw.reselect) && curr_gw)
Marek Lindnercaa0bf62012-08-04 04:13:26 +0000261 goto out;
262
Sven Eckelmann1409a832012-05-12 18:33:55 +0200263 next_gw = batadv_gw_get_best_gw_node(bat_priv);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200264
265 if (curr_gw == next_gw)
266 goto out;
267
268 if (next_gw) {
Antonio Quartulli19595e02011-06-12 11:58:58 +0200269 sprintf(gw_addr, "%pM", next_gw->orig_node->orig);
270
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100271 router = batadv_orig_router_get(next_gw->orig_node,
272 BATADV_IF_DEFAULT);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200273 if (!router) {
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100274 batadv_gw_reselect(bat_priv);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200275 goto out;
276 }
Simon Wunderlich89652332013-11-13 19:14:46 +0100277
278 router_ifinfo = batadv_neigh_ifinfo_get(router,
279 BATADV_IF_DEFAULT);
280 if (!router_ifinfo) {
281 batadv_gw_reselect(bat_priv);
282 goto out;
283 }
Antonio Quartulli2265c142011-04-27 00:22:00 +0200284 }
285
286 if ((curr_gw) && (!next_gw)) {
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200287 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
Sven Eckelmann1eda58b2012-05-12 13:48:58 +0200288 "Removing selected gateway - no gateway in range\n");
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200289 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_DEL,
290 NULL);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200291 } else if ((!curr_gw) && (next_gw)) {
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200292 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
Marek Lindner414254e2013-04-23 21:39:58 +0800293 "Adding route to gateway %pM (bandwidth: %u.%u/%u.%u MBit, tq: %i)\n",
Sven Eckelmann1eda58b2012-05-12 13:48:58 +0200294 next_gw->orig_node->orig,
Marek Lindner414254e2013-04-23 21:39:58 +0800295 next_gw->bandwidth_down / 10,
296 next_gw->bandwidth_down % 10,
297 next_gw->bandwidth_up / 10,
Simon Wunderlich89652332013-11-13 19:14:46 +0100298 next_gw->bandwidth_up % 10,
299 router_ifinfo->bat_iv.tq_avg);
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200300 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_ADD,
301 gw_addr);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200302 } else {
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200303 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
Marek Lindner414254e2013-04-23 21:39:58 +0800304 "Changing route to gateway %pM (bandwidth: %u.%u/%u.%u MBit, tq: %i)\n",
Sven Eckelmann1eda58b2012-05-12 13:48:58 +0200305 next_gw->orig_node->orig,
Marek Lindner414254e2013-04-23 21:39:58 +0800306 next_gw->bandwidth_down / 10,
307 next_gw->bandwidth_down % 10,
308 next_gw->bandwidth_up / 10,
Simon Wunderlich89652332013-11-13 19:14:46 +0100309 next_gw->bandwidth_up % 10,
310 router_ifinfo->bat_iv.tq_avg);
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200311 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_CHANGE,
312 gw_addr);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200313 }
314
Sven Eckelmann1409a832012-05-12 18:33:55 +0200315 batadv_gw_select(bat_priv, next_gw);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200316
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100317out:
318 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200319 batadv_gw_node_free_ref(curr_gw);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200320 if (next_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200321 batadv_gw_node_free_ref(next_gw);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200322 if (router)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200323 batadv_neigh_node_free_ref(router);
Simon Wunderlich89652332013-11-13 19:14:46 +0100324 if (router_ifinfo)
325 batadv_neigh_ifinfo_free_ref(router_ifinfo);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000326}
327
Sven Eckelmann56303d32012-06-05 22:31:31 +0200328void batadv_gw_check_election(struct batadv_priv *bat_priv,
329 struct batadv_orig_node *orig_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000330{
Simon Wunderlich89652332013-11-13 19:14:46 +0100331 struct batadv_neigh_ifinfo *router_orig_tq = NULL;
332 struct batadv_neigh_ifinfo *router_gw_tq = NULL;
Sven Eckelmann56303d32012-06-05 22:31:31 +0200333 struct batadv_orig_node *curr_gw_orig;
334 struct batadv_neigh_node *router_gw = NULL, *router_orig = NULL;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000335 uint8_t gw_tq_avg, orig_tq_avg;
336
Sven Eckelmann7cf06bc2012-05-12 02:09:29 +0200337 curr_gw_orig = batadv_gw_get_selected_orig(bat_priv);
Linus Lüssing57f0c072011-03-14 22:43:33 +0000338 if (!curr_gw_orig)
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100339 goto reselect;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000340
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100341 router_gw = batadv_orig_router_get(curr_gw_orig, BATADV_IF_DEFAULT);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000342 if (!router_gw)
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100343 goto reselect;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000344
Simon Wunderlich89652332013-11-13 19:14:46 +0100345 router_gw_tq = batadv_neigh_ifinfo_get(router_gw,
346 BATADV_IF_DEFAULT);
347 if (!router_gw_tq)
348 goto reselect;
349
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000350 /* this node already is the gateway */
Linus Lüssing57f0c072011-03-14 22:43:33 +0000351 if (curr_gw_orig == orig_node)
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000352 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000353
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100354 router_orig = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000355 if (!router_orig)
356 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000357
Simon Wunderlich89652332013-11-13 19:14:46 +0100358 router_orig_tq = batadv_neigh_ifinfo_get(router_orig,
359 BATADV_IF_DEFAULT);
360 if (!router_orig_tq)
361 goto out;
362
363 gw_tq_avg = router_gw_tq->bat_iv.tq_avg;
364 orig_tq_avg = router_orig_tq->bat_iv.tq_avg;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000365
366 /* the TQ value has to be better */
367 if (orig_tq_avg < gw_tq_avg)
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000368 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000369
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200370 /* if the routing class is greater than 3 the value tells us how much
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000371 * greater the TQ value of the new gateway must be
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200372 */
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000373 if ((atomic_read(&bat_priv->gw_sel_class) > 3) &&
374 (orig_tq_avg - gw_tq_avg < atomic_read(&bat_priv->gw_sel_class)))
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000375 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000376
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200377 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
Sven Eckelmann1eda58b2012-05-12 13:48:58 +0200378 "Restarting gateway selection: better gateway found (tq curr: %i, tq new: %i)\n",
379 gw_tq_avg, orig_tq_avg);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000380
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100381reselect:
382 batadv_gw_reselect(bat_priv);
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000383out:
Linus Lüssing57f0c072011-03-14 22:43:33 +0000384 if (curr_gw_orig)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200385 batadv_orig_node_free_ref(curr_gw_orig);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000386 if (router_gw)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200387 batadv_neigh_node_free_ref(router_gw);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000388 if (router_orig)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200389 batadv_neigh_node_free_ref(router_orig);
Simon Wunderlich89652332013-11-13 19:14:46 +0100390 if (router_gw_tq)
391 batadv_neigh_ifinfo_free_ref(router_gw_tq);
392 if (router_orig_tq)
393 batadv_neigh_ifinfo_free_ref(router_orig_tq);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000394}
395
Marek Lindner414254e2013-04-23 21:39:58 +0800396/**
397 * batadv_gw_node_add - add gateway node to list of available gateways
398 * @bat_priv: the bat priv with all the soft interface information
399 * @orig_node: originator announcing gateway capabilities
400 * @gateway: announced bandwidth information
401 */
Sven Eckelmann56303d32012-06-05 22:31:31 +0200402static void batadv_gw_node_add(struct batadv_priv *bat_priv,
403 struct batadv_orig_node *orig_node,
Marek Lindner414254e2013-04-23 21:39:58 +0800404 struct batadv_tvlv_gateway_data *gateway)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000405{
Sven Eckelmann56303d32012-06-05 22:31:31 +0200406 struct batadv_gw_node *gw_node;
Marek Lindner414254e2013-04-23 21:39:58 +0800407
408 if (gateway->bandwidth_down == 0)
409 return;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000410
Antonio Quartulli377fe0f2014-05-02 01:35:13 +0200411 if (!atomic_inc_not_zero(&orig_node->refcount))
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000412 return;
413
Antonio Quartulli377fe0f2014-05-02 01:35:13 +0200414 gw_node = kzalloc(sizeof(*gw_node), GFP_ATOMIC);
415 if (!gw_node) {
416 batadv_orig_node_free_ref(orig_node);
417 return;
418 }
419
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000420 INIT_HLIST_NODE(&gw_node->list);
421 gw_node->orig_node = orig_node;
Marek Lindner25b6d3c2011-02-10 14:33:49 +0000422 atomic_set(&gw_node->refcount, 1);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000423
Sven Eckelmann807736f2012-07-15 22:26:51 +0200424 spin_lock_bh(&bat_priv->gw.list_lock);
425 hlist_add_head_rcu(&gw_node->list, &bat_priv->gw.list);
426 spin_unlock_bh(&bat_priv->gw.list_lock);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000427
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200428 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
Marek Lindner414254e2013-04-23 21:39:58 +0800429 "Found new gateway %pM -> gw bandwidth: %u.%u/%u.%u MBit\n",
430 orig_node->orig,
431 ntohl(gateway->bandwidth_down) / 10,
432 ntohl(gateway->bandwidth_down) % 10,
433 ntohl(gateway->bandwidth_up) / 10,
434 ntohl(gateway->bandwidth_up) % 10);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000435}
436
Marek Lindner414254e2013-04-23 21:39:58 +0800437/**
438 * batadv_gw_node_get - retrieve gateway node from list of available gateways
439 * @bat_priv: the bat priv with all the soft interface information
440 * @orig_node: originator announcing gateway capabilities
441 *
442 * Returns gateway node if found or NULL otherwise.
443 */
444static struct batadv_gw_node *
445batadv_gw_node_get(struct batadv_priv *bat_priv,
446 struct batadv_orig_node *orig_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000447{
Marek Lindner414254e2013-04-23 21:39:58 +0800448 struct batadv_gw_node *gw_node_tmp, *gw_node = NULL;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000449
450 rcu_read_lock();
Marek Lindner414254e2013-04-23 21:39:58 +0800451 hlist_for_each_entry_rcu(gw_node_tmp, &bat_priv->gw.list, list) {
452 if (gw_node_tmp->orig_node != orig_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000453 continue;
454
Marek Lindner414254e2013-04-23 21:39:58 +0800455 if (gw_node_tmp->deleted)
456 continue;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000457
Marek Lindner414254e2013-04-23 21:39:58 +0800458 if (!atomic_inc_not_zero(&gw_node_tmp->refcount))
459 continue;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000460
Marek Lindner414254e2013-04-23 21:39:58 +0800461 gw_node = gw_node_tmp;
462 break;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000463 }
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100464 rcu_read_unlock();
Antonio Quartulli71e4aa92011-04-25 22:44:32 +0200465
Marek Lindner414254e2013-04-23 21:39:58 +0800466 return gw_node;
467}
468
469/**
470 * batadv_gw_node_update - update list of available gateways with changed
471 * bandwidth information
472 * @bat_priv: the bat priv with all the soft interface information
473 * @orig_node: originator announcing gateway capabilities
474 * @gateway: announced bandwidth information
475 */
476void batadv_gw_node_update(struct batadv_priv *bat_priv,
477 struct batadv_orig_node *orig_node,
478 struct batadv_tvlv_gateway_data *gateway)
479{
480 struct batadv_gw_node *gw_node, *curr_gw = NULL;
481
482 gw_node = batadv_gw_node_get(bat_priv, orig_node);
483 if (!gw_node) {
484 batadv_gw_node_add(bat_priv, orig_node, gateway);
485 goto out;
486 }
487
488 if ((gw_node->bandwidth_down == ntohl(gateway->bandwidth_down)) &&
489 (gw_node->bandwidth_up == ntohl(gateway->bandwidth_up)))
490 goto out;
491
492 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
493 "Gateway bandwidth of originator %pM changed from %u.%u/%u.%u MBit to %u.%u/%u.%u MBit\n",
494 orig_node->orig,
495 gw_node->bandwidth_down / 10,
496 gw_node->bandwidth_down % 10,
497 gw_node->bandwidth_up / 10,
498 gw_node->bandwidth_up % 10,
499 ntohl(gateway->bandwidth_down) / 10,
500 ntohl(gateway->bandwidth_down) % 10,
501 ntohl(gateway->bandwidth_up) / 10,
502 ntohl(gateway->bandwidth_up) % 10);
503
504 gw_node->bandwidth_down = ntohl(gateway->bandwidth_down);
505 gw_node->bandwidth_up = ntohl(gateway->bandwidth_up);
506
507 gw_node->deleted = 0;
508 if (ntohl(gateway->bandwidth_down) == 0) {
509 gw_node->deleted = jiffies;
510 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
511 "Gateway %pM removed from gateway list\n",
512 orig_node->orig);
513
514 /* Note: We don't need a NULL check here, since curr_gw never
515 * gets dereferenced.
516 */
517 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
518 if (gw_node == curr_gw)
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100519 batadv_gw_reselect(bat_priv);
Marek Lindner414254e2013-04-23 21:39:58 +0800520 }
521
522out:
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100523 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200524 batadv_gw_node_free_ref(curr_gw);
Marek Lindner414254e2013-04-23 21:39:58 +0800525 if (gw_node)
526 batadv_gw_node_free_ref(gw_node);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000527}
528
Sven Eckelmann56303d32012-06-05 22:31:31 +0200529void batadv_gw_node_delete(struct batadv_priv *bat_priv,
530 struct batadv_orig_node *orig_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000531{
Marek Lindner414254e2013-04-23 21:39:58 +0800532 struct batadv_tvlv_gateway_data gateway;
533
534 gateway.bandwidth_down = 0;
535 gateway.bandwidth_up = 0;
536
537 batadv_gw_node_update(bat_priv, orig_node, &gateway);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000538}
539
Sven Eckelmann56303d32012-06-05 22:31:31 +0200540void batadv_gw_node_purge(struct batadv_priv *bat_priv)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000541{
Sven Eckelmann56303d32012-06-05 22:31:31 +0200542 struct batadv_gw_node *gw_node, *curr_gw;
Sasha Levinb67bfe02013-02-27 17:06:00 -0800543 struct hlist_node *node_tmp;
Sven Eckelmann42d0b042012-06-03 22:19:17 +0200544 unsigned long timeout = msecs_to_jiffies(2 * BATADV_PURGE_TIMEOUT);
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100545 int do_reselect = 0;
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100546
Sven Eckelmann1409a832012-05-12 18:33:55 +0200547 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000548
Sven Eckelmann807736f2012-07-15 22:26:51 +0200549 spin_lock_bh(&bat_priv->gw.list_lock);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000550
Sasha Levinb67bfe02013-02-27 17:06:00 -0800551 hlist_for_each_entry_safe(gw_node, node_tmp,
Sven Eckelmann807736f2012-07-15 22:26:51 +0200552 &bat_priv->gw.list, list) {
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000553 if (((!gw_node->deleted) ||
554 (time_before(jiffies, gw_node->deleted + timeout))) &&
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200555 atomic_read(&bat_priv->mesh_state) == BATADV_MESH_ACTIVE)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000556 continue;
557
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100558 if (curr_gw == gw_node)
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100559 do_reselect = 1;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000560
561 hlist_del_rcu(&gw_node->list);
Sven Eckelmann1409a832012-05-12 18:33:55 +0200562 batadv_gw_node_free_ref(gw_node);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000563 }
564
Sven Eckelmann807736f2012-07-15 22:26:51 +0200565 spin_unlock_bh(&bat_priv->gw.list_lock);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100566
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100567 /* gw_reselect() needs to acquire the gw_list_lock */
568 if (do_reselect)
569 batadv_gw_reselect(bat_priv);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100570
571 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200572 batadv_gw_node_free_ref(curr_gw);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000573}
574
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200575/* fails if orig_node has no router */
Sven Eckelmann56303d32012-06-05 22:31:31 +0200576static int batadv_write_buffer_text(struct batadv_priv *bat_priv,
577 struct seq_file *seq,
578 const struct batadv_gw_node *gw_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000579{
Sven Eckelmann56303d32012-06-05 22:31:31 +0200580 struct batadv_gw_node *curr_gw;
581 struct batadv_neigh_node *router;
Simon Wunderlich89652332013-11-13 19:14:46 +0100582 struct batadv_neigh_ifinfo *router_ifinfo = NULL;
Marek Lindner414254e2013-04-23 21:39:58 +0800583 int ret = -1;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000584
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100585 router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000586 if (!router)
587 goto out;
588
Simon Wunderlich89652332013-11-13 19:14:46 +0100589 router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
590 if (!router_ifinfo)
591 goto out;
592
Sven Eckelmann1409a832012-05-12 18:33:55 +0200593 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000594
Marek Lindner414254e2013-04-23 21:39:58 +0800595 ret = seq_printf(seq, "%s %pM (%3i) %pM [%10s]: %u.%u/%u.%u MBit\n",
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100596 (curr_gw == gw_node ? "=>" : " "),
597 gw_node->orig_node->orig,
Simon Wunderlich89652332013-11-13 19:14:46 +0100598 router_ifinfo->bat_iv.tq_avg, router->addr,
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100599 router->if_incoming->net_dev->name,
Marek Lindner414254e2013-04-23 21:39:58 +0800600 gw_node->bandwidth_down / 10,
601 gw_node->bandwidth_down % 10,
602 gw_node->bandwidth_up / 10,
603 gw_node->bandwidth_up % 10);
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000604
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100605 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200606 batadv_gw_node_free_ref(curr_gw);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000607out:
Simon Wunderlich89652332013-11-13 19:14:46 +0100608 if (router_ifinfo)
609 batadv_neigh_ifinfo_free_ref(router_ifinfo);
610 if (router)
611 batadv_neigh_node_free_ref(router);
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000612 return ret;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000613}
614
Sven Eckelmann7cf06bc2012-05-12 02:09:29 +0200615int batadv_gw_client_seq_print_text(struct seq_file *seq, void *offset)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000616{
617 struct net_device *net_dev = (struct net_device *)seq->private;
Sven Eckelmann56303d32012-06-05 22:31:31 +0200618 struct batadv_priv *bat_priv = netdev_priv(net_dev);
619 struct batadv_hard_iface *primary_if;
620 struct batadv_gw_node *gw_node;
Marek Lindner30da63a2012-08-03 17:15:46 +0200621 int gw_count = 0;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000622
Marek Lindner30da63a2012-08-03 17:15:46 +0200623 primary_if = batadv_seq_print_text_primary_if_get(seq);
624 if (!primary_if)
Marek Lindner32ae9b22011-04-20 15:40:58 +0200625 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000626
Sven Eckelmann86ceb362012-03-07 09:07:45 +0100627 seq_printf(seq,
Marek Lindner414254e2013-04-23 21:39:58 +0800628 " %-12s (%s/%i) %17s [%10s]: advertised uplink bandwidth ... [B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s)]\n",
Sven Eckelmann42d0b042012-06-03 22:19:17 +0200629 "Gateway", "#", BATADV_TQ_MAX_VALUE, "Nexthop", "outgoingIF",
630 BATADV_SOURCE_VERSION, primary_if->net_dev->name,
Marek Lindner32ae9b22011-04-20 15:40:58 +0200631 primary_if->net_dev->dev_addr, net_dev->name);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000632
633 rcu_read_lock();
Sasha Levinb67bfe02013-02-27 17:06:00 -0800634 hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000635 if (gw_node->deleted)
636 continue;
637
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000638 /* fails if orig_node has no router */
Sven Eckelmann1409a832012-05-12 18:33:55 +0200639 if (batadv_write_buffer_text(bat_priv, seq, gw_node) < 0)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000640 continue;
641
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000642 gw_count++;
643 }
644 rcu_read_unlock();
645
646 if (gw_count == 0)
Antonio Quartulli0c814652013-03-21 09:23:29 +0100647 seq_puts(seq, "No gateways in range ...\n");
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000648
Marek Lindner32ae9b22011-04-20 15:40:58 +0200649out:
650 if (primary_if)
Sven Eckelmanne5d89252012-05-12 13:48:54 +0200651 batadv_hardif_free_ref(primary_if);
Marek Lindner30da63a2012-08-03 17:15:46 +0200652 return 0;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000653}
654
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100655/**
656 * batadv_gw_dhcp_recipient_get - check if a packet is a DHCP message
657 * @skb: the packet to check
658 * @header_len: a pointer to the batman-adv header size
659 * @chaddr: buffer where the client address will be stored. Valid
660 * only if the function returns BATADV_DHCP_TO_CLIENT
661 *
662 * Returns:
663 * - BATADV_DHCP_NO if the packet is not a dhcp message or if there was an error
664 * while parsing it
665 * - BATADV_DHCP_TO_SERVER if this is a message going to the DHCP server
666 * - BATADV_DHCP_TO_CLIENT if this is a message going to a DHCP client
667 *
668 * This function may re-allocate the data buffer of the skb passed as argument.
669 */
670enum batadv_dhcp_recipient
671batadv_gw_dhcp_recipient_get(struct sk_buff *skb, unsigned int *header_len,
672 uint8_t *chaddr)
Antonio Quartulli43676ab52011-04-26 21:31:45 +0200673{
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100674 enum batadv_dhcp_recipient ret = BATADV_DHCP_NO;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000675 struct ethhdr *ethhdr;
676 struct iphdr *iphdr;
677 struct ipv6hdr *ipv6hdr;
678 struct udphdr *udphdr;
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200679 struct vlan_ethhdr *vhdr;
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100680 int chaddr_offset;
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200681 __be16 proto;
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100682 uint8_t *p;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000683
684 /* check for ethernet header */
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200685 if (!pskb_may_pull(skb, *header_len + ETH_HLEN))
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100686 return BATADV_DHCP_NO;
687
Linus Lüssing927c2ed2014-01-19 22:22:45 +0100688 ethhdr = eth_hdr(skb);
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200689 proto = ethhdr->h_proto;
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200690 *header_len += ETH_HLEN;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000691
692 /* check for initial vlan header */
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200693 if (proto == htons(ETH_P_8021Q)) {
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200694 if (!pskb_may_pull(skb, *header_len + VLAN_HLEN))
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100695 return BATADV_DHCP_NO;
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200696
Linus Lüssing927c2ed2014-01-19 22:22:45 +0100697 vhdr = vlan_eth_hdr(skb);
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200698 proto = vhdr->h_vlan_encapsulated_proto;
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200699 *header_len += VLAN_HLEN;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000700 }
701
702 /* check for ip header */
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200703 switch (proto) {
704 case htons(ETH_P_IP):
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200705 if (!pskb_may_pull(skb, *header_len + sizeof(*iphdr)))
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100706 return BATADV_DHCP_NO;
707
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200708 iphdr = (struct iphdr *)(skb->data + *header_len);
709 *header_len += iphdr->ihl * 4;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000710
711 /* check for udp header */
712 if (iphdr->protocol != IPPROTO_UDP)
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100713 return BATADV_DHCP_NO;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000714
715 break;
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200716 case htons(ETH_P_IPV6):
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200717 if (!pskb_may_pull(skb, *header_len + sizeof(*ipv6hdr)))
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100718 return BATADV_DHCP_NO;
719
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200720 ipv6hdr = (struct ipv6hdr *)(skb->data + *header_len);
721 *header_len += sizeof(*ipv6hdr);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000722
723 /* check for udp header */
724 if (ipv6hdr->nexthdr != IPPROTO_UDP)
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100725 return BATADV_DHCP_NO;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000726
727 break;
728 default:
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100729 return BATADV_DHCP_NO;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000730 }
731
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200732 if (!pskb_may_pull(skb, *header_len + sizeof(*udphdr)))
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100733 return BATADV_DHCP_NO;
Linus Lüssing9d2c9482013-08-06 20:21:15 +0200734
735 /* skb->data might have been reallocated by pskb_may_pull() */
Linus Lüssing927c2ed2014-01-19 22:22:45 +0100736 ethhdr = eth_hdr(skb);
Linus Lüssing9d2c9482013-08-06 20:21:15 +0200737 if (ntohs(ethhdr->h_proto) == ETH_P_8021Q)
738 ethhdr = (struct ethhdr *)(skb->data + VLAN_HLEN);
739
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200740 udphdr = (struct udphdr *)(skb->data + *header_len);
741 *header_len += sizeof(*udphdr);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000742
743 /* check for bootp port */
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100744 switch (proto) {
745 case htons(ETH_P_IP):
746 if (udphdr->dest == htons(67))
747 ret = BATADV_DHCP_TO_SERVER;
748 else if (udphdr->source == htons(67))
749 ret = BATADV_DHCP_TO_CLIENT;
750 break;
751 case htons(ETH_P_IPV6):
752 if (udphdr->dest == htons(547))
753 ret = BATADV_DHCP_TO_SERVER;
754 else if (udphdr->source == htons(547))
755 ret = BATADV_DHCP_TO_CLIENT;
756 break;
757 }
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000758
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100759 chaddr_offset = *header_len + BATADV_DHCP_CHADDR_OFFSET;
760 /* store the client address if the message is going to a client */
761 if (ret == BATADV_DHCP_TO_CLIENT &&
762 pskb_may_pull(skb, chaddr_offset + ETH_ALEN)) {
763 /* check if the DHCP packet carries an Ethernet DHCP */
764 p = skb->data + *header_len + BATADV_DHCP_HTYPE_OFFSET;
765 if (*p != BATADV_DHCP_HTYPE_ETHERNET)
766 return BATADV_DHCP_NO;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000767
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100768 /* check if the DHCP packet carries a valid Ethernet address */
769 p = skb->data + *header_len + BATADV_DHCP_HLEN_OFFSET;
770 if (*p != ETH_ALEN)
771 return BATADV_DHCP_NO;
772
Antonio Quartulli8fdd0152014-01-22 00:42:11 +0100773 ether_addr_copy(chaddr, skb->data + chaddr_offset);
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100774 }
775
776 return ret;
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200777}
Antonio Quartullibbb877e2013-06-04 12:11:42 +0200778/**
779 * batadv_gw_out_of_range - check if the dhcp request destination is the best gw
780 * @bat_priv: the bat priv with all the soft interface information
781 * @skb: the outgoing packet
782 *
783 * Check if the skb is a DHCP request and if it is sent to the current best GW
784 * server. Due to topology changes it may be the case that the GW server
785 * previously selected is not the best one anymore.
786 *
787 * Returns true if the packet destination is unicast and it is not the best gw,
788 * false otherwise.
789 *
790 * This call might reallocate skb data.
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100791 * Must be invoked only when the DHCP packet is going TO a DHCP SERVER.
Antonio Quartullibbb877e2013-06-04 12:11:42 +0200792 */
Sven Eckelmann56303d32012-06-05 22:31:31 +0200793bool batadv_gw_out_of_range(struct batadv_priv *bat_priv,
Linus Lüssing9d2c9482013-08-06 20:21:15 +0200794 struct sk_buff *skb)
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200795{
Sven Eckelmann56303d32012-06-05 22:31:31 +0200796 struct batadv_neigh_node *neigh_curr = NULL, *neigh_old = NULL;
797 struct batadv_orig_node *orig_dst_node = NULL;
Marek Lindner414254e2013-04-23 21:39:58 +0800798 struct batadv_gw_node *gw_node = NULL, *curr_gw = NULL;
Simon Wunderlich89652332013-11-13 19:14:46 +0100799 struct batadv_neigh_ifinfo *curr_ifinfo, *old_ifinfo;
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100800 struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
801 bool out_of_range = false;
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200802 uint8_t curr_tq_avg;
Antonio Quartullibbb877e2013-06-04 12:11:42 +0200803 unsigned short vid;
804
805 vid = batadv_get_vid(skb, 0);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000806
Sven Eckelmann08c36d32012-05-12 02:09:39 +0200807 orig_dst_node = batadv_transtable_search(bat_priv, ethhdr->h_source,
Antonio Quartullibbb877e2013-06-04 12:11:42 +0200808 ethhdr->h_dest, vid);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200809 if (!orig_dst_node)
810 goto out;
811
Marek Lindner414254e2013-04-23 21:39:58 +0800812 gw_node = batadv_gw_node_get(bat_priv, orig_dst_node);
Antonio Quartulli0d164492014-12-20 13:48:57 +0100813 if (!gw_node)
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200814 goto out;
815
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200816 switch (atomic_read(&bat_priv->gw_mode)) {
Sven Eckelmanncd646ab2012-06-03 22:19:18 +0200817 case BATADV_GW_MODE_SERVER:
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200818 /* If we are a GW then we are our best GW. We can artificially
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200819 * set the tq towards ourself as the maximum value
820 */
Sven Eckelmann42d0b042012-06-03 22:19:17 +0200821 curr_tq_avg = BATADV_TQ_MAX_VALUE;
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200822 break;
Sven Eckelmanncd646ab2012-06-03 22:19:18 +0200823 case BATADV_GW_MODE_CLIENT:
Sven Eckelmann1409a832012-05-12 18:33:55 +0200824 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200825 if (!curr_gw)
826 goto out;
827
828 /* packet is going to our gateway */
829 if (curr_gw->orig_node == orig_dst_node)
830 goto out;
831
832 /* If the dhcp packet has been sent to a different gw,
833 * we have to evaluate whether the old gw is still
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200834 * reliable enough
835 */
Sven Eckelmann30d3c512012-05-12 02:09:36 +0200836 neigh_curr = batadv_find_router(bat_priv, curr_gw->orig_node,
837 NULL);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200838 if (!neigh_curr)
839 goto out;
840
Simon Wunderlich89652332013-11-13 19:14:46 +0100841 curr_ifinfo = batadv_neigh_ifinfo_get(neigh_curr,
842 BATADV_IF_DEFAULT);
843 if (!curr_ifinfo)
844 goto out;
845
846 curr_tq_avg = curr_ifinfo->bat_iv.tq_avg;
847 batadv_neigh_ifinfo_free_ref(curr_ifinfo);
848
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200849 break;
Sven Eckelmanncd646ab2012-06-03 22:19:18 +0200850 case BATADV_GW_MODE_OFF:
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200851 default:
852 goto out;
Antonio Quartulli43676ab52011-04-26 21:31:45 +0200853 }
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200854
Sven Eckelmann30d3c512012-05-12 02:09:36 +0200855 neigh_old = batadv_find_router(bat_priv, orig_dst_node, NULL);
Dan Carpenter2ef04f42011-11-29 09:09:09 +0300856 if (!neigh_old)
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200857 goto out;
858
Simon Wunderlich89652332013-11-13 19:14:46 +0100859 old_ifinfo = batadv_neigh_ifinfo_get(neigh_old, BATADV_IF_DEFAULT);
860 if (!old_ifinfo)
861 goto out;
862
863 if ((curr_tq_avg - old_ifinfo->bat_iv.tq_avg) > BATADV_GW_THRESHOLD)
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200864 out_of_range = true;
Simon Wunderlich89652332013-11-13 19:14:46 +0100865 batadv_neigh_ifinfo_free_ref(old_ifinfo);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200866
867out:
868 if (orig_dst_node)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200869 batadv_orig_node_free_ref(orig_dst_node);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200870 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200871 batadv_gw_node_free_ref(curr_gw);
Marek Lindner414254e2013-04-23 21:39:58 +0800872 if (gw_node)
873 batadv_gw_node_free_ref(gw_node);
Antonio Quartulli43676ab52011-04-26 21:31:45 +0200874 if (neigh_old)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200875 batadv_neigh_node_free_ref(neigh_old);
Antonio Quartulli43676ab52011-04-26 21:31:45 +0200876 if (neigh_curr)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200877 batadv_neigh_node_free_ref(neigh_curr);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200878 return out_of_range;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000879}