blob: 55cf2260d295b6f4002d438ed34b52382ed7eeea [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{
45 if (atomic_dec_and_test(&gw_node->refcount))
Paul E. McKenneyeb340b22011-05-01 23:25:02 -070046 kfree_rcu(gw_node, rcu);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000047}
48
Sven Eckelmann56303d32012-06-05 22:31:31 +020049static struct batadv_gw_node *
50batadv_gw_get_selected_gw_node(struct batadv_priv *bat_priv)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000051{
Sven Eckelmann56303d32012-06-05 22:31:31 +020052 struct batadv_gw_node *gw_node;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000053
Linus Lüssing5d02b3c2011-02-13 21:13:02 +000054 rcu_read_lock();
Sven Eckelmann807736f2012-07-15 22:26:51 +020055 gw_node = rcu_dereference(bat_priv->gw.curr_gw);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010056 if (!gw_node)
Linus Lüssing5d02b3c2011-02-13 21:13:02 +000057 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000058
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010059 if (!atomic_inc_not_zero(&gw_node->refcount))
60 gw_node = NULL;
61
62out:
63 rcu_read_unlock();
64 return gw_node;
65}
66
Sven Eckelmann56303d32012-06-05 22:31:31 +020067struct batadv_orig_node *
68batadv_gw_get_selected_orig(struct batadv_priv *bat_priv)
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010069{
Sven Eckelmann56303d32012-06-05 22:31:31 +020070 struct batadv_gw_node *gw_node;
71 struct batadv_orig_node *orig_node = NULL;
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010072
Sven Eckelmann1409a832012-05-12 18:33:55 +020073 gw_node = batadv_gw_get_selected_gw_node(bat_priv);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010074 if (!gw_node)
Marek Lindner7b36e8e2011-02-18 12:28:10 +000075 goto out;
Linus Lüssing5d02b3c2011-02-13 21:13:02 +000076
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010077 rcu_read_lock();
78 orig_node = gw_node->orig_node;
79 if (!orig_node)
80 goto unlock;
81
Marek Lindner7b36e8e2011-02-18 12:28:10 +000082 if (!atomic_inc_not_zero(&orig_node->refcount))
83 orig_node = NULL;
Linus Lüssing43c70ad2011-02-13 21:13:04 +000084
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010085unlock:
Linus Lüssing5d02b3c2011-02-13 21:13:02 +000086 rcu_read_unlock();
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010087out:
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000088 if (gw_node)
Sven Eckelmann1409a832012-05-12 18:33:55 +020089 batadv_gw_node_free_ref(gw_node);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010090 return orig_node;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000091}
92
Sven Eckelmann56303d32012-06-05 22:31:31 +020093static void batadv_gw_select(struct batadv_priv *bat_priv,
94 struct batadv_gw_node *new_gw_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000095{
Sven Eckelmann56303d32012-06-05 22:31:31 +020096 struct batadv_gw_node *curr_gw_node;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000097
Sven Eckelmann807736f2012-07-15 22:26:51 +020098 spin_lock_bh(&bat_priv->gw.list_lock);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010099
Marek Lindner25b6d3c2011-02-10 14:33:49 +0000100 if (new_gw_node && !atomic_inc_not_zero(&new_gw_node->refcount))
101 new_gw_node = NULL;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000102
Sven Eckelmann807736f2012-07-15 22:26:51 +0200103 curr_gw_node = rcu_dereference_protected(bat_priv->gw.curr_gw, 1);
104 rcu_assign_pointer(bat_priv->gw.curr_gw, new_gw_node);
Marek Lindner25b6d3c2011-02-10 14:33:49 +0000105
106 if (curr_gw_node)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200107 batadv_gw_node_free_ref(curr_gw_node);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100108
Sven Eckelmann807736f2012-07-15 22:26:51 +0200109 spin_unlock_bh(&bat_priv->gw.list_lock);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100110}
111
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100112/**
113 * batadv_gw_reselect - force a gateway reselection
114 * @bat_priv: the bat priv with all the soft interface information
115 *
116 * Set a flag to remind the GW component to perform a new gateway reselection.
117 * However this function does not ensure that the current gateway is going to be
118 * deselected. The reselection mechanism may elect the same gateway once again.
119 *
120 * This means that invoking batadv_gw_reselect() does not guarantee a gateway
121 * change and therefore a uevent is not necessarily expected.
122 */
123void batadv_gw_reselect(struct batadv_priv *bat_priv)
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100124{
Sven Eckelmann807736f2012-07-15 22:26:51 +0200125 atomic_set(&bat_priv->gw.reselect, 1);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000126}
127
Sven Eckelmann56303d32012-06-05 22:31:31 +0200128static struct batadv_gw_node *
129batadv_gw_get_best_gw_node(struct batadv_priv *bat_priv)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000130{
Sven Eckelmann56303d32012-06-05 22:31:31 +0200131 struct batadv_neigh_node *router;
Simon Wunderlich89652332013-11-13 19:14:46 +0100132 struct batadv_neigh_ifinfo *router_ifinfo;
Sven Eckelmann56303d32012-06-05 22:31:31 +0200133 struct batadv_gw_node *gw_node, *curr_gw = NULL;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000134 uint32_t max_gw_factor = 0, tmp_gw_factor = 0;
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200135 uint32_t gw_divisor;
Antonio Quartulli2265c142011-04-27 00:22:00 +0200136 uint8_t max_tq = 0;
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200137 uint8_t tq_avg;
Sven Eckelmann56303d32012-06-05 22:31:31 +0200138 struct batadv_orig_node *orig_node;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000139
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200140 gw_divisor = BATADV_TQ_LOCAL_WINDOW_SIZE * BATADV_TQ_LOCAL_WINDOW_SIZE;
141 gw_divisor *= 64;
142
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000143 rcu_read_lock();
Sasha Levinb67bfe02013-02-27 17:06:00 -0800144 hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000145 if (gw_node->deleted)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000146 continue;
147
Sven Eckelmann84d5e5e2012-05-12 02:09:30 +0200148 orig_node = gw_node->orig_node;
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100149 router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000150 if (!router)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000151 continue;
152
Simon Wunderlich89652332013-11-13 19:14:46 +0100153 router_ifinfo = batadv_neigh_ifinfo_get(router,
154 BATADV_IF_DEFAULT);
155 if (!router_ifinfo)
156 goto next;
157
Antonio Quartulli2265c142011-04-27 00:22:00 +0200158 if (!atomic_inc_not_zero(&gw_node->refcount))
159 goto next;
160
Simon Wunderlich89652332013-11-13 19:14:46 +0100161 tq_avg = router_ifinfo->bat_iv.tq_avg;
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200162
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000163 switch (atomic_read(&bat_priv->gw_sel_class)) {
164 case 1: /* fast connection */
Marek Lindner414254e2013-04-23 21:39:58 +0800165 tmp_gw_factor = tq_avg * tq_avg;
166 tmp_gw_factor *= gw_node->bandwidth_down;
167 tmp_gw_factor *= 100 * 100;
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200168 tmp_gw_factor /= gw_divisor;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000169
170 if ((tmp_gw_factor > max_gw_factor) ||
171 ((tmp_gw_factor == max_gw_factor) &&
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200172 (tq_avg > max_tq))) {
Antonio Quartulli2265c142011-04-27 00:22:00 +0200173 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200174 batadv_gw_node_free_ref(curr_gw);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200175 curr_gw = gw_node;
176 atomic_inc(&curr_gw->refcount);
177 }
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000178 break;
179
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200180 default: /* 2: stable connection (use best statistic)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000181 * 3: fast-switch (use best statistic but change as
182 * soon as a better gateway appears)
183 * XX: late-switch (use best statistic but change as
184 * soon as a better gateway appears which has
185 * $routing_class more tq points)
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200186 */
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200187 if (tq_avg > max_tq) {
Antonio Quartulli2265c142011-04-27 00:22:00 +0200188 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200189 batadv_gw_node_free_ref(curr_gw);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200190 curr_gw = gw_node;
191 atomic_inc(&curr_gw->refcount);
192 }
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000193 break;
194 }
195
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200196 if (tq_avg > max_tq)
197 max_tq = tq_avg;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000198
199 if (tmp_gw_factor > max_gw_factor)
200 max_gw_factor = tmp_gw_factor;
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000201
Sven Eckelmann1409a832012-05-12 18:33:55 +0200202 batadv_gw_node_free_ref(gw_node);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200203
204next:
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200205 batadv_neigh_node_free_ref(router);
Simon Wunderlich89652332013-11-13 19:14:46 +0100206 if (router_ifinfo)
207 batadv_neigh_ifinfo_free_ref(router_ifinfo);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000208 }
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000209 rcu_read_unlock();
Antonio Quartulli2265c142011-04-27 00:22:00 +0200210
211 return curr_gw;
212}
213
Antonio Quartullic6eaa3f2013-07-13 00:06:00 +0200214/**
215 * batadv_gw_check_client_stop - check if client mode has been switched off
216 * @bat_priv: the bat priv with all the soft interface information
217 *
218 * This function assumes the caller has checked that the gw state *is actually
219 * changing*. This function is not supposed to be called when there is no state
220 * change.
221 */
222void batadv_gw_check_client_stop(struct batadv_priv *bat_priv)
223{
224 struct batadv_gw_node *curr_gw;
225
226 if (atomic_read(&bat_priv->gw_mode) != BATADV_GW_MODE_CLIENT)
227 return;
228
229 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
230 if (!curr_gw)
231 return;
232
Antonio Quartullif3163182013-11-04 20:59:40 +0100233 /* deselect the current gateway so that next time that client mode is
234 * enabled a proper GW_ADD event can be sent
235 */
236 batadv_gw_select(bat_priv, NULL);
237
Antonio Quartullic6eaa3f2013-07-13 00:06:00 +0200238 /* if batman-adv is switching the gw client mode off and a gateway was
239 * already selected, send a DEL uevent
240 */
241 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_DEL, NULL);
242
243 batadv_gw_node_free_ref(curr_gw);
244}
245
Sven Eckelmann56303d32012-06-05 22:31:31 +0200246void batadv_gw_election(struct batadv_priv *bat_priv)
Antonio Quartulli2265c142011-04-27 00:22:00 +0200247{
Sven Eckelmann56303d32012-06-05 22:31:31 +0200248 struct batadv_gw_node *curr_gw = NULL, *next_gw = NULL;
249 struct batadv_neigh_node *router = NULL;
Simon Wunderlich89652332013-11-13 19:14:46 +0100250 struct batadv_neigh_ifinfo *router_ifinfo = NULL;
Antonio Quartulli19595e02011-06-12 11:58:58 +0200251 char gw_addr[18] = { '\0' };
Antonio Quartulli2265c142011-04-27 00:22:00 +0200252
Sven Eckelmanncd646ab2012-06-03 22:19:18 +0200253 if (atomic_read(&bat_priv->gw_mode) != BATADV_GW_MODE_CLIENT)
Antonio Quartulli2265c142011-04-27 00:22:00 +0200254 goto out;
255
Sven Eckelmann1409a832012-05-12 18:33:55 +0200256 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200257
Sven Eckelmann807736f2012-07-15 22:26:51 +0200258 if (!batadv_atomic_dec_not_zero(&bat_priv->gw.reselect) && curr_gw)
Marek Lindnercaa0bf62012-08-04 04:13:26 +0000259 goto out;
260
Sven Eckelmann1409a832012-05-12 18:33:55 +0200261 next_gw = batadv_gw_get_best_gw_node(bat_priv);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200262
263 if (curr_gw == next_gw)
264 goto out;
265
266 if (next_gw) {
Antonio Quartulli19595e02011-06-12 11:58:58 +0200267 sprintf(gw_addr, "%pM", next_gw->orig_node->orig);
268
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100269 router = batadv_orig_router_get(next_gw->orig_node,
270 BATADV_IF_DEFAULT);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200271 if (!router) {
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100272 batadv_gw_reselect(bat_priv);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200273 goto out;
274 }
Simon Wunderlich89652332013-11-13 19:14:46 +0100275
276 router_ifinfo = batadv_neigh_ifinfo_get(router,
277 BATADV_IF_DEFAULT);
278 if (!router_ifinfo) {
279 batadv_gw_reselect(bat_priv);
280 goto out;
281 }
Antonio Quartulli2265c142011-04-27 00:22:00 +0200282 }
283
284 if ((curr_gw) && (!next_gw)) {
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200285 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
Sven Eckelmann1eda58b2012-05-12 13:48:58 +0200286 "Removing selected gateway - no gateway in range\n");
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200287 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_DEL,
288 NULL);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200289 } else if ((!curr_gw) && (next_gw)) {
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200290 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
Marek Lindner414254e2013-04-23 21:39:58 +0800291 "Adding route to gateway %pM (bandwidth: %u.%u/%u.%u MBit, tq: %i)\n",
Sven Eckelmann1eda58b2012-05-12 13:48:58 +0200292 next_gw->orig_node->orig,
Marek Lindner414254e2013-04-23 21:39:58 +0800293 next_gw->bandwidth_down / 10,
294 next_gw->bandwidth_down % 10,
295 next_gw->bandwidth_up / 10,
Simon Wunderlich89652332013-11-13 19:14:46 +0100296 next_gw->bandwidth_up % 10,
297 router_ifinfo->bat_iv.tq_avg);
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200298 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_ADD,
299 gw_addr);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200300 } else {
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200301 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
Marek Lindner414254e2013-04-23 21:39:58 +0800302 "Changing route to gateway %pM (bandwidth: %u.%u/%u.%u MBit, tq: %i)\n",
Sven Eckelmann1eda58b2012-05-12 13:48:58 +0200303 next_gw->orig_node->orig,
Marek Lindner414254e2013-04-23 21:39:58 +0800304 next_gw->bandwidth_down / 10,
305 next_gw->bandwidth_down % 10,
306 next_gw->bandwidth_up / 10,
Simon Wunderlich89652332013-11-13 19:14:46 +0100307 next_gw->bandwidth_up % 10,
308 router_ifinfo->bat_iv.tq_avg);
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200309 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_CHANGE,
310 gw_addr);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200311 }
312
Sven Eckelmann1409a832012-05-12 18:33:55 +0200313 batadv_gw_select(bat_priv, next_gw);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200314
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100315out:
316 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200317 batadv_gw_node_free_ref(curr_gw);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200318 if (next_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200319 batadv_gw_node_free_ref(next_gw);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200320 if (router)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200321 batadv_neigh_node_free_ref(router);
Simon Wunderlich89652332013-11-13 19:14:46 +0100322 if (router_ifinfo)
323 batadv_neigh_ifinfo_free_ref(router_ifinfo);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000324}
325
Sven Eckelmann56303d32012-06-05 22:31:31 +0200326void batadv_gw_check_election(struct batadv_priv *bat_priv,
327 struct batadv_orig_node *orig_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000328{
Simon Wunderlich89652332013-11-13 19:14:46 +0100329 struct batadv_neigh_ifinfo *router_orig_tq = NULL;
330 struct batadv_neigh_ifinfo *router_gw_tq = NULL;
Sven Eckelmann56303d32012-06-05 22:31:31 +0200331 struct batadv_orig_node *curr_gw_orig;
332 struct batadv_neigh_node *router_gw = NULL, *router_orig = NULL;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000333 uint8_t gw_tq_avg, orig_tq_avg;
334
Sven Eckelmann7cf06bc2012-05-12 02:09:29 +0200335 curr_gw_orig = batadv_gw_get_selected_orig(bat_priv);
Linus Lüssing57f0c072011-03-14 22:43:33 +0000336 if (!curr_gw_orig)
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100337 goto reselect;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000338
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100339 router_gw = batadv_orig_router_get(curr_gw_orig, BATADV_IF_DEFAULT);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000340 if (!router_gw)
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100341 goto reselect;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000342
Simon Wunderlich89652332013-11-13 19:14:46 +0100343 router_gw_tq = batadv_neigh_ifinfo_get(router_gw,
344 BATADV_IF_DEFAULT);
345 if (!router_gw_tq)
346 goto reselect;
347
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000348 /* this node already is the gateway */
Linus Lüssing57f0c072011-03-14 22:43:33 +0000349 if (curr_gw_orig == orig_node)
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000350 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000351
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100352 router_orig = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000353 if (!router_orig)
354 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000355
Simon Wunderlich89652332013-11-13 19:14:46 +0100356 router_orig_tq = batadv_neigh_ifinfo_get(router_orig,
357 BATADV_IF_DEFAULT);
358 if (!router_orig_tq)
359 goto out;
360
361 gw_tq_avg = router_gw_tq->bat_iv.tq_avg;
362 orig_tq_avg = router_orig_tq->bat_iv.tq_avg;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000363
364 /* the TQ value has to be better */
365 if (orig_tq_avg < gw_tq_avg)
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000366 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000367
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200368 /* if the routing class is greater than 3 the value tells us how much
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000369 * greater the TQ value of the new gateway must be
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200370 */
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000371 if ((atomic_read(&bat_priv->gw_sel_class) > 3) &&
372 (orig_tq_avg - gw_tq_avg < atomic_read(&bat_priv->gw_sel_class)))
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000373 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000374
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200375 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
Sven Eckelmann1eda58b2012-05-12 13:48:58 +0200376 "Restarting gateway selection: better gateway found (tq curr: %i, tq new: %i)\n",
377 gw_tq_avg, orig_tq_avg);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000378
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100379reselect:
380 batadv_gw_reselect(bat_priv);
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000381out:
Linus Lüssing57f0c072011-03-14 22:43:33 +0000382 if (curr_gw_orig)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200383 batadv_orig_node_free_ref(curr_gw_orig);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000384 if (router_gw)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200385 batadv_neigh_node_free_ref(router_gw);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000386 if (router_orig)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200387 batadv_neigh_node_free_ref(router_orig);
Simon Wunderlich89652332013-11-13 19:14:46 +0100388 if (router_gw_tq)
389 batadv_neigh_ifinfo_free_ref(router_gw_tq);
390 if (router_orig_tq)
391 batadv_neigh_ifinfo_free_ref(router_orig_tq);
Linus Lüssing57f0c072011-03-14 22:43:33 +0000392
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000393 return;
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
Sven Eckelmann704509b2011-05-14 23:14:54 +0200411 gw_node = kzalloc(sizeof(*gw_node), GFP_ATOMIC);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000412 if (!gw_node)
413 return;
414
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000415 INIT_HLIST_NODE(&gw_node->list);
416 gw_node->orig_node = orig_node;
Marek Lindner25b6d3c2011-02-10 14:33:49 +0000417 atomic_set(&gw_node->refcount, 1);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000418
Sven Eckelmann807736f2012-07-15 22:26:51 +0200419 spin_lock_bh(&bat_priv->gw.list_lock);
420 hlist_add_head_rcu(&gw_node->list, &bat_priv->gw.list);
421 spin_unlock_bh(&bat_priv->gw.list_lock);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000422
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200423 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
Marek Lindner414254e2013-04-23 21:39:58 +0800424 "Found new gateway %pM -> gw bandwidth: %u.%u/%u.%u MBit\n",
425 orig_node->orig,
426 ntohl(gateway->bandwidth_down) / 10,
427 ntohl(gateway->bandwidth_down) % 10,
428 ntohl(gateway->bandwidth_up) / 10,
429 ntohl(gateway->bandwidth_up) % 10);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000430}
431
Marek Lindner414254e2013-04-23 21:39:58 +0800432/**
433 * batadv_gw_node_get - retrieve gateway node from list of available gateways
434 * @bat_priv: the bat priv with all the soft interface information
435 * @orig_node: originator announcing gateway capabilities
436 *
437 * Returns gateway node if found or NULL otherwise.
438 */
439static struct batadv_gw_node *
440batadv_gw_node_get(struct batadv_priv *bat_priv,
441 struct batadv_orig_node *orig_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000442{
Marek Lindner414254e2013-04-23 21:39:58 +0800443 struct batadv_gw_node *gw_node_tmp, *gw_node = NULL;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000444
445 rcu_read_lock();
Marek Lindner414254e2013-04-23 21:39:58 +0800446 hlist_for_each_entry_rcu(gw_node_tmp, &bat_priv->gw.list, list) {
447 if (gw_node_tmp->orig_node != orig_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000448 continue;
449
Marek Lindner414254e2013-04-23 21:39:58 +0800450 if (gw_node_tmp->deleted)
451 continue;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000452
Marek Lindner414254e2013-04-23 21:39:58 +0800453 if (!atomic_inc_not_zero(&gw_node_tmp->refcount))
454 continue;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000455
Marek Lindner414254e2013-04-23 21:39:58 +0800456 gw_node = gw_node_tmp;
457 break;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000458 }
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100459 rcu_read_unlock();
Antonio Quartulli71e4aa92011-04-25 22:44:32 +0200460
Marek Lindner414254e2013-04-23 21:39:58 +0800461 return gw_node;
462}
463
464/**
465 * batadv_gw_node_update - update list of available gateways with changed
466 * bandwidth information
467 * @bat_priv: the bat priv with all the soft interface information
468 * @orig_node: originator announcing gateway capabilities
469 * @gateway: announced bandwidth information
470 */
471void batadv_gw_node_update(struct batadv_priv *bat_priv,
472 struct batadv_orig_node *orig_node,
473 struct batadv_tvlv_gateway_data *gateway)
474{
475 struct batadv_gw_node *gw_node, *curr_gw = NULL;
476
477 gw_node = batadv_gw_node_get(bat_priv, orig_node);
478 if (!gw_node) {
479 batadv_gw_node_add(bat_priv, orig_node, gateway);
480 goto out;
481 }
482
483 if ((gw_node->bandwidth_down == ntohl(gateway->bandwidth_down)) &&
484 (gw_node->bandwidth_up == ntohl(gateway->bandwidth_up)))
485 goto out;
486
487 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
488 "Gateway bandwidth of originator %pM changed from %u.%u/%u.%u MBit to %u.%u/%u.%u MBit\n",
489 orig_node->orig,
490 gw_node->bandwidth_down / 10,
491 gw_node->bandwidth_down % 10,
492 gw_node->bandwidth_up / 10,
493 gw_node->bandwidth_up % 10,
494 ntohl(gateway->bandwidth_down) / 10,
495 ntohl(gateway->bandwidth_down) % 10,
496 ntohl(gateway->bandwidth_up) / 10,
497 ntohl(gateway->bandwidth_up) % 10);
498
499 gw_node->bandwidth_down = ntohl(gateway->bandwidth_down);
500 gw_node->bandwidth_up = ntohl(gateway->bandwidth_up);
501
502 gw_node->deleted = 0;
503 if (ntohl(gateway->bandwidth_down) == 0) {
504 gw_node->deleted = jiffies;
505 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
506 "Gateway %pM removed from gateway list\n",
507 orig_node->orig);
508
509 /* Note: We don't need a NULL check here, since curr_gw never
510 * gets dereferenced.
511 */
512 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
513 if (gw_node == curr_gw)
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100514 batadv_gw_reselect(bat_priv);
Marek Lindner414254e2013-04-23 21:39:58 +0800515 }
516
517out:
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100518 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200519 batadv_gw_node_free_ref(curr_gw);
Marek Lindner414254e2013-04-23 21:39:58 +0800520 if (gw_node)
521 batadv_gw_node_free_ref(gw_node);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000522}
523
Sven Eckelmann56303d32012-06-05 22:31:31 +0200524void batadv_gw_node_delete(struct batadv_priv *bat_priv,
525 struct batadv_orig_node *orig_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000526{
Marek Lindner414254e2013-04-23 21:39:58 +0800527 struct batadv_tvlv_gateway_data gateway;
528
529 gateway.bandwidth_down = 0;
530 gateway.bandwidth_up = 0;
531
532 batadv_gw_node_update(bat_priv, orig_node, &gateway);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000533}
534
Sven Eckelmann56303d32012-06-05 22:31:31 +0200535void batadv_gw_node_purge(struct batadv_priv *bat_priv)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000536{
Sven Eckelmann56303d32012-06-05 22:31:31 +0200537 struct batadv_gw_node *gw_node, *curr_gw;
Sasha Levinb67bfe02013-02-27 17:06:00 -0800538 struct hlist_node *node_tmp;
Sven Eckelmann42d0b042012-06-03 22:19:17 +0200539 unsigned long timeout = msecs_to_jiffies(2 * BATADV_PURGE_TIMEOUT);
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100540 int do_reselect = 0;
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100541
Sven Eckelmann1409a832012-05-12 18:33:55 +0200542 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000543
Sven Eckelmann807736f2012-07-15 22:26:51 +0200544 spin_lock_bh(&bat_priv->gw.list_lock);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000545
Sasha Levinb67bfe02013-02-27 17:06:00 -0800546 hlist_for_each_entry_safe(gw_node, node_tmp,
Sven Eckelmann807736f2012-07-15 22:26:51 +0200547 &bat_priv->gw.list, list) {
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000548 if (((!gw_node->deleted) ||
549 (time_before(jiffies, gw_node->deleted + timeout))) &&
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200550 atomic_read(&bat_priv->mesh_state) == BATADV_MESH_ACTIVE)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000551 continue;
552
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100553 if (curr_gw == gw_node)
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100554 do_reselect = 1;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000555
556 hlist_del_rcu(&gw_node->list);
Sven Eckelmann1409a832012-05-12 18:33:55 +0200557 batadv_gw_node_free_ref(gw_node);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000558 }
559
Sven Eckelmann807736f2012-07-15 22:26:51 +0200560 spin_unlock_bh(&bat_priv->gw.list_lock);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100561
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100562 /* gw_reselect() needs to acquire the gw_list_lock */
563 if (do_reselect)
564 batadv_gw_reselect(bat_priv);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100565
566 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200567 batadv_gw_node_free_ref(curr_gw);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000568}
569
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200570/* fails if orig_node has no router */
Sven Eckelmann56303d32012-06-05 22:31:31 +0200571static int batadv_write_buffer_text(struct batadv_priv *bat_priv,
572 struct seq_file *seq,
573 const struct batadv_gw_node *gw_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000574{
Sven Eckelmann56303d32012-06-05 22:31:31 +0200575 struct batadv_gw_node *curr_gw;
576 struct batadv_neigh_node *router;
Simon Wunderlich89652332013-11-13 19:14:46 +0100577 struct batadv_neigh_ifinfo *router_ifinfo = NULL;
Marek Lindner414254e2013-04-23 21:39:58 +0800578 int ret = -1;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000579
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100580 router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000581 if (!router)
582 goto out;
583
Simon Wunderlich89652332013-11-13 19:14:46 +0100584 router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
585 if (!router_ifinfo)
586 goto out;
587
Sven Eckelmann1409a832012-05-12 18:33:55 +0200588 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000589
Marek Lindner414254e2013-04-23 21:39:58 +0800590 ret = seq_printf(seq, "%s %pM (%3i) %pM [%10s]: %u.%u/%u.%u MBit\n",
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100591 (curr_gw == gw_node ? "=>" : " "),
592 gw_node->orig_node->orig,
Simon Wunderlich89652332013-11-13 19:14:46 +0100593 router_ifinfo->bat_iv.tq_avg, router->addr,
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100594 router->if_incoming->net_dev->name,
Marek Lindner414254e2013-04-23 21:39:58 +0800595 gw_node->bandwidth_down / 10,
596 gw_node->bandwidth_down % 10,
597 gw_node->bandwidth_up / 10,
598 gw_node->bandwidth_up % 10);
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000599
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100600 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200601 batadv_gw_node_free_ref(curr_gw);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000602out:
Simon Wunderlich89652332013-11-13 19:14:46 +0100603 if (router_ifinfo)
604 batadv_neigh_ifinfo_free_ref(router_ifinfo);
605 if (router)
606 batadv_neigh_node_free_ref(router);
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000607 return ret;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000608}
609
Sven Eckelmann7cf06bc2012-05-12 02:09:29 +0200610int batadv_gw_client_seq_print_text(struct seq_file *seq, void *offset)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000611{
612 struct net_device *net_dev = (struct net_device *)seq->private;
Sven Eckelmann56303d32012-06-05 22:31:31 +0200613 struct batadv_priv *bat_priv = netdev_priv(net_dev);
614 struct batadv_hard_iface *primary_if;
615 struct batadv_gw_node *gw_node;
Marek Lindner30da63a2012-08-03 17:15:46 +0200616 int gw_count = 0;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000617
Marek Lindner30da63a2012-08-03 17:15:46 +0200618 primary_if = batadv_seq_print_text_primary_if_get(seq);
619 if (!primary_if)
Marek Lindner32ae9b22011-04-20 15:40:58 +0200620 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000621
Sven Eckelmann86ceb362012-03-07 09:07:45 +0100622 seq_printf(seq,
Marek Lindner414254e2013-04-23 21:39:58 +0800623 " %-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 +0200624 "Gateway", "#", BATADV_TQ_MAX_VALUE, "Nexthop", "outgoingIF",
625 BATADV_SOURCE_VERSION, primary_if->net_dev->name,
Marek Lindner32ae9b22011-04-20 15:40:58 +0200626 primary_if->net_dev->dev_addr, net_dev->name);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000627
628 rcu_read_lock();
Sasha Levinb67bfe02013-02-27 17:06:00 -0800629 hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000630 if (gw_node->deleted)
631 continue;
632
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000633 /* fails if orig_node has no router */
Sven Eckelmann1409a832012-05-12 18:33:55 +0200634 if (batadv_write_buffer_text(bat_priv, seq, gw_node) < 0)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000635 continue;
636
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000637 gw_count++;
638 }
639 rcu_read_unlock();
640
641 if (gw_count == 0)
Antonio Quartulli0c814652013-03-21 09:23:29 +0100642 seq_puts(seq, "No gateways in range ...\n");
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000643
Marek Lindner32ae9b22011-04-20 15:40:58 +0200644out:
645 if (primary_if)
Sven Eckelmanne5d89252012-05-12 13:48:54 +0200646 batadv_hardif_free_ref(primary_if);
Marek Lindner30da63a2012-08-03 17:15:46 +0200647 return 0;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000648}
649
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100650/**
651 * batadv_gw_dhcp_recipient_get - check if a packet is a DHCP message
652 * @skb: the packet to check
653 * @header_len: a pointer to the batman-adv header size
654 * @chaddr: buffer where the client address will be stored. Valid
655 * only if the function returns BATADV_DHCP_TO_CLIENT
656 *
657 * Returns:
658 * - BATADV_DHCP_NO if the packet is not a dhcp message or if there was an error
659 * while parsing it
660 * - BATADV_DHCP_TO_SERVER if this is a message going to the DHCP server
661 * - BATADV_DHCP_TO_CLIENT if this is a message going to a DHCP client
662 *
663 * This function may re-allocate the data buffer of the skb passed as argument.
664 */
665enum batadv_dhcp_recipient
666batadv_gw_dhcp_recipient_get(struct sk_buff *skb, unsigned int *header_len,
667 uint8_t *chaddr)
Antonio Quartulli43676ab52011-04-26 21:31:45 +0200668{
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100669 enum batadv_dhcp_recipient ret = BATADV_DHCP_NO;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000670 struct ethhdr *ethhdr;
671 struct iphdr *iphdr;
672 struct ipv6hdr *ipv6hdr;
673 struct udphdr *udphdr;
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200674 struct vlan_ethhdr *vhdr;
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100675 int chaddr_offset;
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200676 __be16 proto;
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100677 uint8_t *p;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000678
679 /* check for ethernet header */
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200680 if (!pskb_may_pull(skb, *header_len + ETH_HLEN))
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100681 return BATADV_DHCP_NO;
682
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000683 ethhdr = (struct ethhdr *)skb->data;
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200684 proto = ethhdr->h_proto;
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200685 *header_len += ETH_HLEN;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000686
687 /* check for initial vlan header */
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200688 if (proto == htons(ETH_P_8021Q)) {
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200689 if (!pskb_may_pull(skb, *header_len + VLAN_HLEN))
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100690 return BATADV_DHCP_NO;
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200691
692 vhdr = (struct vlan_ethhdr *)skb->data;
693 proto = vhdr->h_vlan_encapsulated_proto;
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200694 *header_len += VLAN_HLEN;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000695 }
696
697 /* check for ip header */
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200698 switch (proto) {
699 case htons(ETH_P_IP):
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200700 if (!pskb_may_pull(skb, *header_len + sizeof(*iphdr)))
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100701 return BATADV_DHCP_NO;
702
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200703 iphdr = (struct iphdr *)(skb->data + *header_len);
704 *header_len += iphdr->ihl * 4;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000705
706 /* check for udp header */
707 if (iphdr->protocol != IPPROTO_UDP)
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100708 return BATADV_DHCP_NO;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000709
710 break;
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200711 case htons(ETH_P_IPV6):
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200712 if (!pskb_may_pull(skb, *header_len + sizeof(*ipv6hdr)))
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100713 return BATADV_DHCP_NO;
714
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200715 ipv6hdr = (struct ipv6hdr *)(skb->data + *header_len);
716 *header_len += sizeof(*ipv6hdr);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000717
718 /* check for udp header */
719 if (ipv6hdr->nexthdr != IPPROTO_UDP)
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100720 return BATADV_DHCP_NO;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000721
722 break;
723 default:
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100724 return BATADV_DHCP_NO;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000725 }
726
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200727 if (!pskb_may_pull(skb, *header_len + sizeof(*udphdr)))
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100728 return BATADV_DHCP_NO;
Linus Lüssing9d2c9482013-08-06 20:21:15 +0200729
730 /* skb->data might have been reallocated by pskb_may_pull() */
731 ethhdr = (struct ethhdr *)skb->data;
732 if (ntohs(ethhdr->h_proto) == ETH_P_8021Q)
733 ethhdr = (struct ethhdr *)(skb->data + VLAN_HLEN);
734
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200735 udphdr = (struct udphdr *)(skb->data + *header_len);
736 *header_len += sizeof(*udphdr);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000737
738 /* check for bootp port */
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100739 switch (proto) {
740 case htons(ETH_P_IP):
741 if (udphdr->dest == htons(67))
742 ret = BATADV_DHCP_TO_SERVER;
743 else if (udphdr->source == htons(67))
744 ret = BATADV_DHCP_TO_CLIENT;
745 break;
746 case htons(ETH_P_IPV6):
747 if (udphdr->dest == htons(547))
748 ret = BATADV_DHCP_TO_SERVER;
749 else if (udphdr->source == htons(547))
750 ret = BATADV_DHCP_TO_CLIENT;
751 break;
752 }
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000753
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100754 chaddr_offset = *header_len + BATADV_DHCP_CHADDR_OFFSET;
755 /* store the client address if the message is going to a client */
756 if (ret == BATADV_DHCP_TO_CLIENT &&
757 pskb_may_pull(skb, chaddr_offset + ETH_ALEN)) {
758 /* check if the DHCP packet carries an Ethernet DHCP */
759 p = skb->data + *header_len + BATADV_DHCP_HTYPE_OFFSET;
760 if (*p != BATADV_DHCP_HTYPE_ETHERNET)
761 return BATADV_DHCP_NO;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000762
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100763 /* check if the DHCP packet carries a valid Ethernet address */
764 p = skb->data + *header_len + BATADV_DHCP_HLEN_OFFSET;
765 if (*p != ETH_ALEN)
766 return BATADV_DHCP_NO;
767
768 memcpy(chaddr, skb->data + chaddr_offset, ETH_ALEN);
769 }
770
771 return ret;
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200772}
Antonio Quartullibbb877e2013-06-04 12:11:42 +0200773/**
774 * batadv_gw_out_of_range - check if the dhcp request destination is the best gw
775 * @bat_priv: the bat priv with all the soft interface information
776 * @skb: the outgoing packet
777 *
778 * Check if the skb is a DHCP request and if it is sent to the current best GW
779 * server. Due to topology changes it may be the case that the GW server
780 * previously selected is not the best one anymore.
781 *
782 * Returns true if the packet destination is unicast and it is not the best gw,
783 * false otherwise.
784 *
785 * This call might reallocate skb data.
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100786 * Must be invoked only when the DHCP packet is going TO a DHCP SERVER.
Antonio Quartullibbb877e2013-06-04 12:11:42 +0200787 */
Sven Eckelmann56303d32012-06-05 22:31:31 +0200788bool batadv_gw_out_of_range(struct batadv_priv *bat_priv,
Linus Lüssing9d2c9482013-08-06 20:21:15 +0200789 struct sk_buff *skb)
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200790{
Sven Eckelmann56303d32012-06-05 22:31:31 +0200791 struct batadv_neigh_node *neigh_curr = NULL, *neigh_old = NULL;
792 struct batadv_orig_node *orig_dst_node = NULL;
Marek Lindner414254e2013-04-23 21:39:58 +0800793 struct batadv_gw_node *gw_node = NULL, *curr_gw = NULL;
Simon Wunderlich89652332013-11-13 19:14:46 +0100794 struct batadv_neigh_ifinfo *curr_ifinfo, *old_ifinfo;
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100795 struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
796 bool out_of_range = false;
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200797 uint8_t curr_tq_avg;
Antonio Quartullibbb877e2013-06-04 12:11:42 +0200798 unsigned short vid;
799
800 vid = batadv_get_vid(skb, 0);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000801
Sven Eckelmann08c36d32012-05-12 02:09:39 +0200802 orig_dst_node = batadv_transtable_search(bat_priv, ethhdr->h_source,
Antonio Quartullibbb877e2013-06-04 12:11:42 +0200803 ethhdr->h_dest, vid);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200804 if (!orig_dst_node)
805 goto out;
806
Marek Lindner414254e2013-04-23 21:39:58 +0800807 gw_node = batadv_gw_node_get(bat_priv, orig_dst_node);
808 if (!gw_node->bandwidth_down == 0)
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200809 goto out;
810
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200811 switch (atomic_read(&bat_priv->gw_mode)) {
Sven Eckelmanncd646ab2012-06-03 22:19:18 +0200812 case BATADV_GW_MODE_SERVER:
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200813 /* If we are a GW then we are our best GW. We can artificially
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200814 * set the tq towards ourself as the maximum value
815 */
Sven Eckelmann42d0b042012-06-03 22:19:17 +0200816 curr_tq_avg = BATADV_TQ_MAX_VALUE;
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200817 break;
Sven Eckelmanncd646ab2012-06-03 22:19:18 +0200818 case BATADV_GW_MODE_CLIENT:
Sven Eckelmann1409a832012-05-12 18:33:55 +0200819 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200820 if (!curr_gw)
821 goto out;
822
823 /* packet is going to our gateway */
824 if (curr_gw->orig_node == orig_dst_node)
825 goto out;
826
827 /* If the dhcp packet has been sent to a different gw,
828 * we have to evaluate whether the old gw is still
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200829 * reliable enough
830 */
Sven Eckelmann30d3c512012-05-12 02:09:36 +0200831 neigh_curr = batadv_find_router(bat_priv, curr_gw->orig_node,
832 NULL);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200833 if (!neigh_curr)
834 goto out;
835
Simon Wunderlich89652332013-11-13 19:14:46 +0100836 curr_ifinfo = batadv_neigh_ifinfo_get(neigh_curr,
837 BATADV_IF_DEFAULT);
838 if (!curr_ifinfo)
839 goto out;
840
841 curr_tq_avg = curr_ifinfo->bat_iv.tq_avg;
842 batadv_neigh_ifinfo_free_ref(curr_ifinfo);
843
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200844 break;
Sven Eckelmanncd646ab2012-06-03 22:19:18 +0200845 case BATADV_GW_MODE_OFF:
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200846 default:
847 goto out;
Antonio Quartulli43676ab52011-04-26 21:31:45 +0200848 }
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200849
Sven Eckelmann30d3c512012-05-12 02:09:36 +0200850 neigh_old = batadv_find_router(bat_priv, orig_dst_node, NULL);
Dan Carpenter2ef04f42011-11-29 09:09:09 +0300851 if (!neigh_old)
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200852 goto out;
853
Simon Wunderlich89652332013-11-13 19:14:46 +0100854 old_ifinfo = batadv_neigh_ifinfo_get(neigh_old, BATADV_IF_DEFAULT);
855 if (!old_ifinfo)
856 goto out;
857
858 if ((curr_tq_avg - old_ifinfo->bat_iv.tq_avg) > BATADV_GW_THRESHOLD)
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200859 out_of_range = true;
Simon Wunderlich89652332013-11-13 19:14:46 +0100860 batadv_neigh_ifinfo_free_ref(old_ifinfo);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200861
862out:
863 if (orig_dst_node)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200864 batadv_orig_node_free_ref(orig_dst_node);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200865 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200866 batadv_gw_node_free_ref(curr_gw);
Marek Lindner414254e2013-04-23 21:39:58 +0800867 if (gw_node)
868 batadv_gw_node_free_ref(gw_node);
Antonio Quartulli43676ab52011-04-26 21:31:45 +0200869 if (neigh_old)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200870 batadv_neigh_node_free_ref(neigh_old);
Antonio Quartulli43676ab52011-04-26 21:31:45 +0200871 if (neigh_curr)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200872 batadv_neigh_node_free_ref(neigh_curr);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200873 return out_of_range;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000874}