blob: e6c8382c79ba86dfea5078a37f692f74ebffb01c [file] [log] [blame]
Sven Eckelmann9f6446c2015-04-23 13:16:35 +02001/* Copyright (C) 2009-2015 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
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000018#include "gateway_client.h"
Sven Eckelmann1e2c2a42015-04-17 19:40:28 +020019#include "main.h"
20
21#include <linux/atomic.h>
22#include <linux/byteorder/generic.h>
23#include <linux/etherdevice.h>
24#include <linux/fs.h>
25#include <linux/if_ether.h>
26#include <linux/if_vlan.h>
27#include <linux/in.h>
28#include <linux/ip.h>
29#include <linux/ipv6.h>
Sven Eckelmann1e2c2a42015-04-17 19:40:28 +020030#include <linux/kernel.h>
31#include <linux/list.h>
32#include <linux/netdevice.h>
33#include <linux/rculist.h>
34#include <linux/rcupdate.h>
35#include <linux/seq_file.h>
36#include <linux/skbuff.h>
37#include <linux/slab.h>
38#include <linux/spinlock.h>
39#include <linux/stddef.h>
40#include <linux/udp.h>
41
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000042#include "gateway_common.h"
43#include "hard-interface.h"
Linus Lüssing57f0c072011-03-14 22:43:33 +000044#include "originator.h"
Sven Eckelmann1e2c2a42015-04-17 19:40:28 +020045#include "packet.h"
Antonio Quartulli43676ab2011-04-26 21:31:45 +020046#include "routing.h"
Sven Eckelmann1e2c2a42015-04-17 19:40:28 +020047#include "sysfs.h"
48#include "translation-table.h"
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000049
Antonio Quartulli6c413b12013-11-05 19:31:08 +010050/* These are the offsets of the "hw type" and "hw address length" in the dhcp
51 * packet starting at the beginning of the dhcp header
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +020052 */
Antonio Quartulli6c413b12013-11-05 19:31:08 +010053#define BATADV_DHCP_HTYPE_OFFSET 1
54#define BATADV_DHCP_HLEN_OFFSET 2
55/* Value of htype representing Ethernet */
56#define BATADV_DHCP_HTYPE_ETHERNET 0x01
57/* This is the offset of the "chaddr" field in the dhcp packet starting at the
58 * beginning of the dhcp header
59 */
60#define BATADV_DHCP_CHADDR_OFFSET 28
Antonio Quartulli43676ab2011-04-26 21:31:45 +020061
Sven Eckelmann56303d32012-06-05 22:31:31 +020062static void batadv_gw_node_free_ref(struct batadv_gw_node *gw_node)
Marek Lindner25b6d3c2011-02-10 14:33:49 +000063{
Antonio Quartulli377fe0f2014-05-02 01:35:13 +020064 if (atomic_dec_and_test(&gw_node->refcount)) {
65 batadv_orig_node_free_ref(gw_node->orig_node);
Paul E. McKenneyeb340b22011-05-01 23:25:02 -070066 kfree_rcu(gw_node, rcu);
Antonio Quartulli377fe0f2014-05-02 01:35:13 +020067 }
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000068}
69
Sven Eckelmann56303d32012-06-05 22:31:31 +020070static struct batadv_gw_node *
71batadv_gw_get_selected_gw_node(struct batadv_priv *bat_priv)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000072{
Sven Eckelmann56303d32012-06-05 22:31:31 +020073 struct batadv_gw_node *gw_node;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000074
Linus Lüssing5d02b3c2011-02-13 21:13:02 +000075 rcu_read_lock();
Sven Eckelmann807736f2012-07-15 22:26:51 +020076 gw_node = rcu_dereference(bat_priv->gw.curr_gw);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010077 if (!gw_node)
Linus Lüssing5d02b3c2011-02-13 21:13:02 +000078 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000079
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010080 if (!atomic_inc_not_zero(&gw_node->refcount))
81 gw_node = NULL;
82
83out:
84 rcu_read_unlock();
85 return gw_node;
86}
87
Sven Eckelmann56303d32012-06-05 22:31:31 +020088struct batadv_orig_node *
89batadv_gw_get_selected_orig(struct batadv_priv *bat_priv)
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010090{
Sven Eckelmann56303d32012-06-05 22:31:31 +020091 struct batadv_gw_node *gw_node;
92 struct batadv_orig_node *orig_node = NULL;
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010093
Sven Eckelmann1409a832012-05-12 18:33:55 +020094 gw_node = batadv_gw_get_selected_gw_node(bat_priv);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010095 if (!gw_node)
Marek Lindner7b36e8e2011-02-18 12:28:10 +000096 goto out;
Linus Lüssing5d02b3c2011-02-13 21:13:02 +000097
Marek Lindnerc4aac1a2011-03-23 11:24:34 +010098 rcu_read_lock();
99 orig_node = gw_node->orig_node;
100 if (!orig_node)
101 goto unlock;
102
Marek Lindner7b36e8e2011-02-18 12:28:10 +0000103 if (!atomic_inc_not_zero(&orig_node->refcount))
104 orig_node = NULL;
Linus Lüssing43c70ad2011-02-13 21:13:04 +0000105
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100106unlock:
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000107 rcu_read_unlock();
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100108out:
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000109 if (gw_node)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200110 batadv_gw_node_free_ref(gw_node);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100111 return orig_node;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000112}
113
Sven Eckelmann56303d32012-06-05 22:31:31 +0200114static void batadv_gw_select(struct batadv_priv *bat_priv,
115 struct batadv_gw_node *new_gw_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000116{
Sven Eckelmann56303d32012-06-05 22:31:31 +0200117 struct batadv_gw_node *curr_gw_node;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000118
Sven Eckelmann807736f2012-07-15 22:26:51 +0200119 spin_lock_bh(&bat_priv->gw.list_lock);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100120
Marek Lindner25b6d3c2011-02-10 14:33:49 +0000121 if (new_gw_node && !atomic_inc_not_zero(&new_gw_node->refcount))
122 new_gw_node = NULL;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000123
Sven Eckelmann807736f2012-07-15 22:26:51 +0200124 curr_gw_node = rcu_dereference_protected(bat_priv->gw.curr_gw, 1);
125 rcu_assign_pointer(bat_priv->gw.curr_gw, new_gw_node);
Marek Lindner25b6d3c2011-02-10 14:33:49 +0000126
127 if (curr_gw_node)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200128 batadv_gw_node_free_ref(curr_gw_node);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100129
Sven Eckelmann807736f2012-07-15 22:26:51 +0200130 spin_unlock_bh(&bat_priv->gw.list_lock);
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100131}
132
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100133/**
134 * batadv_gw_reselect - force a gateway reselection
135 * @bat_priv: the bat priv with all the soft interface information
136 *
137 * Set a flag to remind the GW component to perform a new gateway reselection.
138 * However this function does not ensure that the current gateway is going to be
139 * deselected. The reselection mechanism may elect the same gateway once again.
140 *
141 * This means that invoking batadv_gw_reselect() does not guarantee a gateway
142 * change and therefore a uevent is not necessarily expected.
143 */
144void batadv_gw_reselect(struct batadv_priv *bat_priv)
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100145{
Sven Eckelmann807736f2012-07-15 22:26:51 +0200146 atomic_set(&bat_priv->gw.reselect, 1);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000147}
148
Sven Eckelmann56303d32012-06-05 22:31:31 +0200149static struct batadv_gw_node *
150batadv_gw_get_best_gw_node(struct batadv_priv *bat_priv)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000151{
Sven Eckelmann56303d32012-06-05 22:31:31 +0200152 struct batadv_neigh_node *router;
Simon Wunderlich89652332013-11-13 19:14:46 +0100153 struct batadv_neigh_ifinfo *router_ifinfo;
Sven Eckelmann56303d32012-06-05 22:31:31 +0200154 struct batadv_gw_node *gw_node, *curr_gw = NULL;
Sven Eckelmann4f248cf2015-06-09 20:50:49 +0200155 u64 max_gw_factor = 0;
156 u64 tmp_gw_factor = 0;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200157 u8 max_tq = 0;
158 u8 tq_avg;
Sven Eckelmann56303d32012-06-05 22:31:31 +0200159 struct batadv_orig_node *orig_node;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000160
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000161 rcu_read_lock();
Sasha Levinb67bfe02013-02-27 17:06:00 -0800162 hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
Sven Eckelmann84d5e5e2012-05-12 02:09:30 +0200163 orig_node = gw_node->orig_node;
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100164 router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000165 if (!router)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000166 continue;
167
Simon Wunderlich89652332013-11-13 19:14:46 +0100168 router_ifinfo = batadv_neigh_ifinfo_get(router,
169 BATADV_IF_DEFAULT);
170 if (!router_ifinfo)
171 goto next;
172
Antonio Quartulli2265c142011-04-27 00:22:00 +0200173 if (!atomic_inc_not_zero(&gw_node->refcount))
174 goto next;
175
Simon Wunderlich89652332013-11-13 19:14:46 +0100176 tq_avg = router_ifinfo->bat_iv.tq_avg;
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200177
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000178 switch (atomic_read(&bat_priv->gw_sel_class)) {
179 case 1: /* fast connection */
Marek Lindner414254e2013-04-23 21:39:58 +0800180 tmp_gw_factor = tq_avg * tq_avg;
181 tmp_gw_factor *= gw_node->bandwidth_down;
182 tmp_gw_factor *= 100 * 100;
Sven Eckelmanne071d932015-06-22 09:13:23 +0200183 tmp_gw_factor >>= 18;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000184
185 if ((tmp_gw_factor > max_gw_factor) ||
186 ((tmp_gw_factor == max_gw_factor) &&
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200187 (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
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200195 default: /* 2: stable connection (use best statistic)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000196 * 3: fast-switch (use best statistic but change as
197 * soon as a better gateway appears)
198 * XX: late-switch (use best statistic but change as
199 * soon as a better gateway appears which has
200 * $routing_class more tq points)
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200201 */
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200202 if (tq_avg > max_tq) {
Antonio Quartulli2265c142011-04-27 00:22:00 +0200203 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200204 batadv_gw_node_free_ref(curr_gw);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200205 curr_gw = gw_node;
206 atomic_inc(&curr_gw->refcount);
207 }
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000208 break;
209 }
210
Sven Eckelmannc67893d2012-07-08 18:33:51 +0200211 if (tq_avg > max_tq)
212 max_tq = tq_avg;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000213
214 if (tmp_gw_factor > max_gw_factor)
215 max_gw_factor = tmp_gw_factor;
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000216
Sven Eckelmann1409a832012-05-12 18:33:55 +0200217 batadv_gw_node_free_ref(gw_node);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200218
219next:
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200220 batadv_neigh_node_free_ref(router);
Simon Wunderlich89652332013-11-13 19:14:46 +0100221 if (router_ifinfo)
222 batadv_neigh_ifinfo_free_ref(router_ifinfo);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000223 }
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000224 rcu_read_unlock();
Antonio Quartulli2265c142011-04-27 00:22:00 +0200225
226 return curr_gw;
227}
228
Antonio Quartullic6eaa3f2013-07-13 00:06:00 +0200229/**
230 * batadv_gw_check_client_stop - check if client mode has been switched off
231 * @bat_priv: the bat priv with all the soft interface information
232 *
233 * This function assumes the caller has checked that the gw state *is actually
234 * changing*. This function is not supposed to be called when there is no state
235 * change.
236 */
237void batadv_gw_check_client_stop(struct batadv_priv *bat_priv)
238{
239 struct batadv_gw_node *curr_gw;
240
241 if (atomic_read(&bat_priv->gw_mode) != BATADV_GW_MODE_CLIENT)
242 return;
243
244 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
245 if (!curr_gw)
246 return;
247
Antonio Quartullif3163182013-11-04 20:59:40 +0100248 /* deselect the current gateway so that next time that client mode is
249 * enabled a proper GW_ADD event can be sent
250 */
251 batadv_gw_select(bat_priv, NULL);
252
Antonio Quartullic6eaa3f2013-07-13 00:06:00 +0200253 /* if batman-adv is switching the gw client mode off and a gateway was
254 * already selected, send a DEL uevent
255 */
256 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_DEL, NULL);
257
258 batadv_gw_node_free_ref(curr_gw);
259}
260
Sven Eckelmann56303d32012-06-05 22:31:31 +0200261void batadv_gw_election(struct batadv_priv *bat_priv)
Antonio Quartulli2265c142011-04-27 00:22:00 +0200262{
Sven Eckelmann4f248cf2015-06-09 20:50:49 +0200263 struct batadv_gw_node *curr_gw = NULL;
264 struct batadv_gw_node *next_gw = NULL;
Sven Eckelmann56303d32012-06-05 22:31:31 +0200265 struct batadv_neigh_node *router = NULL;
Simon Wunderlich89652332013-11-13 19:14:46 +0100266 struct batadv_neigh_ifinfo *router_ifinfo = NULL;
Antonio Quartulli19595e02011-06-12 11:58:58 +0200267 char gw_addr[18] = { '\0' };
Antonio Quartulli2265c142011-04-27 00:22:00 +0200268
Sven Eckelmanncd646ab2012-06-03 22:19:18 +0200269 if (atomic_read(&bat_priv->gw_mode) != BATADV_GW_MODE_CLIENT)
Antonio Quartulli2265c142011-04-27 00:22:00 +0200270 goto out;
271
Sven Eckelmann1409a832012-05-12 18:33:55 +0200272 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200273
Sven Eckelmann807736f2012-07-15 22:26:51 +0200274 if (!batadv_atomic_dec_not_zero(&bat_priv->gw.reselect) && curr_gw)
Marek Lindnercaa0bf62012-08-04 04:13:26 +0000275 goto out;
276
Sven Eckelmann1409a832012-05-12 18:33:55 +0200277 next_gw = batadv_gw_get_best_gw_node(bat_priv);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200278
279 if (curr_gw == next_gw)
280 goto out;
281
282 if (next_gw) {
Antonio Quartulli19595e02011-06-12 11:58:58 +0200283 sprintf(gw_addr, "%pM", next_gw->orig_node->orig);
284
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100285 router = batadv_orig_router_get(next_gw->orig_node,
286 BATADV_IF_DEFAULT);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200287 if (!router) {
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100288 batadv_gw_reselect(bat_priv);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200289 goto out;
290 }
Simon Wunderlich89652332013-11-13 19:14:46 +0100291
292 router_ifinfo = batadv_neigh_ifinfo_get(router,
293 BATADV_IF_DEFAULT);
294 if (!router_ifinfo) {
295 batadv_gw_reselect(bat_priv);
296 goto out;
297 }
Antonio Quartulli2265c142011-04-27 00:22:00 +0200298 }
299
300 if ((curr_gw) && (!next_gw)) {
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200301 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
Sven Eckelmann1eda58b2012-05-12 13:48:58 +0200302 "Removing selected gateway - no gateway in range\n");
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200303 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_DEL,
304 NULL);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200305 } else if ((!curr_gw) && (next_gw)) {
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200306 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
Marek Lindner414254e2013-04-23 21:39:58 +0800307 "Adding route to gateway %pM (bandwidth: %u.%u/%u.%u MBit, tq: %i)\n",
Sven Eckelmann1eda58b2012-05-12 13:48:58 +0200308 next_gw->orig_node->orig,
Marek Lindner414254e2013-04-23 21:39:58 +0800309 next_gw->bandwidth_down / 10,
310 next_gw->bandwidth_down % 10,
311 next_gw->bandwidth_up / 10,
Simon Wunderlich89652332013-11-13 19:14:46 +0100312 next_gw->bandwidth_up % 10,
313 router_ifinfo->bat_iv.tq_avg);
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200314 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_ADD,
315 gw_addr);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200316 } else {
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200317 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
Marek Lindner414254e2013-04-23 21:39:58 +0800318 "Changing route to gateway %pM (bandwidth: %u.%u/%u.%u MBit, tq: %i)\n",
Sven Eckelmann1eda58b2012-05-12 13:48:58 +0200319 next_gw->orig_node->orig,
Marek Lindner414254e2013-04-23 21:39:58 +0800320 next_gw->bandwidth_down / 10,
321 next_gw->bandwidth_down % 10,
322 next_gw->bandwidth_up / 10,
Simon Wunderlich89652332013-11-13 19:14:46 +0100323 next_gw->bandwidth_up % 10,
324 router_ifinfo->bat_iv.tq_avg);
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200325 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_CHANGE,
326 gw_addr);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200327 }
328
Sven Eckelmann1409a832012-05-12 18:33:55 +0200329 batadv_gw_select(bat_priv, next_gw);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200330
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100331out:
332 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200333 batadv_gw_node_free_ref(curr_gw);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200334 if (next_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200335 batadv_gw_node_free_ref(next_gw);
Antonio Quartulli2265c142011-04-27 00:22:00 +0200336 if (router)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200337 batadv_neigh_node_free_ref(router);
Simon Wunderlich89652332013-11-13 19:14:46 +0100338 if (router_ifinfo)
339 batadv_neigh_ifinfo_free_ref(router_ifinfo);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000340}
341
Sven Eckelmann56303d32012-06-05 22:31:31 +0200342void batadv_gw_check_election(struct batadv_priv *bat_priv,
343 struct batadv_orig_node *orig_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000344{
Simon Wunderlich89652332013-11-13 19:14:46 +0100345 struct batadv_neigh_ifinfo *router_orig_tq = NULL;
346 struct batadv_neigh_ifinfo *router_gw_tq = NULL;
Sven Eckelmann56303d32012-06-05 22:31:31 +0200347 struct batadv_orig_node *curr_gw_orig;
Sven Eckelmann4f248cf2015-06-09 20:50:49 +0200348 struct batadv_neigh_node *router_gw = NULL;
349 struct batadv_neigh_node *router_orig = NULL;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200350 u8 gw_tq_avg, orig_tq_avg;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000351
Sven Eckelmann7cf06bc2012-05-12 02:09:29 +0200352 curr_gw_orig = batadv_gw_get_selected_orig(bat_priv);
Linus Lüssing57f0c072011-03-14 22:43:33 +0000353 if (!curr_gw_orig)
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100354 goto reselect;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000355
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100356 router_gw = batadv_orig_router_get(curr_gw_orig, BATADV_IF_DEFAULT);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000357 if (!router_gw)
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100358 goto reselect;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000359
Simon Wunderlich89652332013-11-13 19:14:46 +0100360 router_gw_tq = batadv_neigh_ifinfo_get(router_gw,
361 BATADV_IF_DEFAULT);
362 if (!router_gw_tq)
363 goto reselect;
364
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000365 /* this node already is the gateway */
Linus Lüssing57f0c072011-03-14 22:43:33 +0000366 if (curr_gw_orig == orig_node)
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000367 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000368
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100369 router_orig = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000370 if (!router_orig)
371 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000372
Simon Wunderlich89652332013-11-13 19:14:46 +0100373 router_orig_tq = batadv_neigh_ifinfo_get(router_orig,
374 BATADV_IF_DEFAULT);
375 if (!router_orig_tq)
376 goto out;
377
378 gw_tq_avg = router_gw_tq->bat_iv.tq_avg;
379 orig_tq_avg = router_orig_tq->bat_iv.tq_avg;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000380
381 /* the TQ value has to be better */
382 if (orig_tq_avg < gw_tq_avg)
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000383 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000384
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200385 /* if the routing class is greater than 3 the value tells us how much
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000386 * greater the TQ value of the new gateway must be
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200387 */
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000388 if ((atomic_read(&bat_priv->gw_sel_class) > 3) &&
389 (orig_tq_avg - gw_tq_avg < atomic_read(&bat_priv->gw_sel_class)))
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000390 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000391
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200392 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
Sven Eckelmann1eda58b2012-05-12 13:48:58 +0200393 "Restarting gateway selection: better gateway found (tq curr: %i, tq new: %i)\n",
394 gw_tq_avg, orig_tq_avg);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000395
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100396reselect:
397 batadv_gw_reselect(bat_priv);
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000398out:
Linus Lüssing57f0c072011-03-14 22:43:33 +0000399 if (curr_gw_orig)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200400 batadv_orig_node_free_ref(curr_gw_orig);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000401 if (router_gw)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200402 batadv_neigh_node_free_ref(router_gw);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000403 if (router_orig)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200404 batadv_neigh_node_free_ref(router_orig);
Simon Wunderlich89652332013-11-13 19:14:46 +0100405 if (router_gw_tq)
406 batadv_neigh_ifinfo_free_ref(router_gw_tq);
407 if (router_orig_tq)
408 batadv_neigh_ifinfo_free_ref(router_orig_tq);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000409}
410
Marek Lindner414254e2013-04-23 21:39:58 +0800411/**
412 * batadv_gw_node_add - add gateway node to list of available gateways
413 * @bat_priv: the bat priv with all the soft interface information
414 * @orig_node: originator announcing gateway capabilities
415 * @gateway: announced bandwidth information
416 */
Sven Eckelmann56303d32012-06-05 22:31:31 +0200417static void batadv_gw_node_add(struct batadv_priv *bat_priv,
418 struct batadv_orig_node *orig_node,
Marek Lindner414254e2013-04-23 21:39:58 +0800419 struct batadv_tvlv_gateway_data *gateway)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000420{
Sven Eckelmann56303d32012-06-05 22:31:31 +0200421 struct batadv_gw_node *gw_node;
Marek Lindner414254e2013-04-23 21:39:58 +0800422
423 if (gateway->bandwidth_down == 0)
424 return;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000425
Antonio Quartulli377fe0f2014-05-02 01:35:13 +0200426 if (!atomic_inc_not_zero(&orig_node->refcount))
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000427 return;
428
Antonio Quartulli377fe0f2014-05-02 01:35:13 +0200429 gw_node = kzalloc(sizeof(*gw_node), GFP_ATOMIC);
430 if (!gw_node) {
431 batadv_orig_node_free_ref(orig_node);
432 return;
433 }
434
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000435 INIT_HLIST_NODE(&gw_node->list);
436 gw_node->orig_node = orig_node;
Simon Wunderlich27a4d5e2015-06-24 14:50:19 +0200437 gw_node->bandwidth_down = ntohl(gateway->bandwidth_down);
438 gw_node->bandwidth_up = ntohl(gateway->bandwidth_up);
Marek Lindner25b6d3c2011-02-10 14:33:49 +0000439 atomic_set(&gw_node->refcount, 1);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000440
Sven Eckelmann807736f2012-07-15 22:26:51 +0200441 spin_lock_bh(&bat_priv->gw.list_lock);
442 hlist_add_head_rcu(&gw_node->list, &bat_priv->gw.list);
443 spin_unlock_bh(&bat_priv->gw.list_lock);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000444
Sven Eckelmann39c75a52012-06-03 22:19:22 +0200445 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
Marek Lindner414254e2013-04-23 21:39:58 +0800446 "Found new gateway %pM -> gw bandwidth: %u.%u/%u.%u MBit\n",
447 orig_node->orig,
448 ntohl(gateway->bandwidth_down) / 10,
449 ntohl(gateway->bandwidth_down) % 10,
450 ntohl(gateway->bandwidth_up) / 10,
451 ntohl(gateway->bandwidth_up) % 10);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000452}
453
Marek Lindner414254e2013-04-23 21:39:58 +0800454/**
455 * batadv_gw_node_get - retrieve gateway node from list of available gateways
456 * @bat_priv: the bat priv with all the soft interface information
457 * @orig_node: originator announcing gateway capabilities
458 *
459 * Returns gateway node if found or NULL otherwise.
460 */
461static struct batadv_gw_node *
462batadv_gw_node_get(struct batadv_priv *bat_priv,
463 struct batadv_orig_node *orig_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000464{
Marek Lindner414254e2013-04-23 21:39:58 +0800465 struct batadv_gw_node *gw_node_tmp, *gw_node = NULL;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000466
467 rcu_read_lock();
Marek Lindner414254e2013-04-23 21:39:58 +0800468 hlist_for_each_entry_rcu(gw_node_tmp, &bat_priv->gw.list, list) {
469 if (gw_node_tmp->orig_node != orig_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000470 continue;
471
Marek Lindner414254e2013-04-23 21:39:58 +0800472 if (!atomic_inc_not_zero(&gw_node_tmp->refcount))
473 continue;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000474
Marek Lindner414254e2013-04-23 21:39:58 +0800475 gw_node = gw_node_tmp;
476 break;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000477 }
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100478 rcu_read_unlock();
Antonio Quartulli71e4aa92011-04-25 22:44:32 +0200479
Marek Lindner414254e2013-04-23 21:39:58 +0800480 return gw_node;
481}
482
483/**
484 * batadv_gw_node_update - update list of available gateways with changed
485 * bandwidth information
486 * @bat_priv: the bat priv with all the soft interface information
487 * @orig_node: originator announcing gateway capabilities
488 * @gateway: announced bandwidth information
489 */
490void batadv_gw_node_update(struct batadv_priv *bat_priv,
491 struct batadv_orig_node *orig_node,
492 struct batadv_tvlv_gateway_data *gateway)
493{
494 struct batadv_gw_node *gw_node, *curr_gw = NULL;
495
496 gw_node = batadv_gw_node_get(bat_priv, orig_node);
497 if (!gw_node) {
498 batadv_gw_node_add(bat_priv, orig_node, gateway);
499 goto out;
500 }
501
502 if ((gw_node->bandwidth_down == ntohl(gateway->bandwidth_down)) &&
503 (gw_node->bandwidth_up == ntohl(gateway->bandwidth_up)))
504 goto out;
505
506 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
507 "Gateway bandwidth of originator %pM changed from %u.%u/%u.%u MBit to %u.%u/%u.%u MBit\n",
508 orig_node->orig,
509 gw_node->bandwidth_down / 10,
510 gw_node->bandwidth_down % 10,
511 gw_node->bandwidth_up / 10,
512 gw_node->bandwidth_up % 10,
513 ntohl(gateway->bandwidth_down) / 10,
514 ntohl(gateway->bandwidth_down) % 10,
515 ntohl(gateway->bandwidth_up) / 10,
516 ntohl(gateway->bandwidth_up) % 10);
517
518 gw_node->bandwidth_down = ntohl(gateway->bandwidth_down);
519 gw_node->bandwidth_up = ntohl(gateway->bandwidth_up);
520
Marek Lindner414254e2013-04-23 21:39:58 +0800521 if (ntohl(gateway->bandwidth_down) == 0) {
Marek Lindner414254e2013-04-23 21:39:58 +0800522 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
523 "Gateway %pM removed from gateway list\n",
524 orig_node->orig);
525
526 /* Note: We don't need a NULL check here, since curr_gw never
527 * gets dereferenced.
528 */
Simon Wunderlichbd3524c2015-08-03 19:13:58 +0200529 spin_lock_bh(&bat_priv->gw.list_lock);
530 hlist_del_init_rcu(&gw_node->list);
531 spin_unlock_bh(&bat_priv->gw.list_lock);
532
533 batadv_gw_node_free_ref(gw_node);
534
Marek Lindner414254e2013-04-23 21:39:58 +0800535 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
536 if (gw_node == curr_gw)
Antonio Quartulli4e820e72013-11-04 20:59:41 +0100537 batadv_gw_reselect(bat_priv);
Simon Wunderlichbd3524c2015-08-03 19:13:58 +0200538
539 if (curr_gw)
540 batadv_gw_node_free_ref(curr_gw);
Marek Lindner414254e2013-04-23 21:39:58 +0800541 }
542
543out:
Marek Lindner414254e2013-04-23 21:39:58 +0800544 if (gw_node)
545 batadv_gw_node_free_ref(gw_node);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000546}
547
Sven Eckelmann56303d32012-06-05 22:31:31 +0200548void batadv_gw_node_delete(struct batadv_priv *bat_priv,
549 struct batadv_orig_node *orig_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000550{
Marek Lindner414254e2013-04-23 21:39:58 +0800551 struct batadv_tvlv_gateway_data gateway;
552
553 gateway.bandwidth_down = 0;
554 gateway.bandwidth_up = 0;
555
556 batadv_gw_node_update(bat_priv, orig_node, &gateway);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000557}
558
Simon Wunderlichbd3524c2015-08-03 19:13:58 +0200559void batadv_gw_node_free(struct batadv_priv *bat_priv)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000560{
Simon Wunderlichbd3524c2015-08-03 19:13:58 +0200561 struct batadv_gw_node *gw_node;
Sasha Levinb67bfe02013-02-27 17:06:00 -0800562 struct hlist_node *node_tmp;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000563
Sven Eckelmann807736f2012-07-15 22:26:51 +0200564 spin_lock_bh(&bat_priv->gw.list_lock);
Sasha Levinb67bfe02013-02-27 17:06:00 -0800565 hlist_for_each_entry_safe(gw_node, node_tmp,
Sven Eckelmann807736f2012-07-15 22:26:51 +0200566 &bat_priv->gw.list, list) {
Simon Wunderlichbd3524c2015-08-03 19:13:58 +0200567 hlist_del_init_rcu(&gw_node->list);
Sven Eckelmann1409a832012-05-12 18:33:55 +0200568 batadv_gw_node_free_ref(gw_node);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000569 }
Sven Eckelmann807736f2012-07-15 22:26:51 +0200570 spin_unlock_bh(&bat_priv->gw.list_lock);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000571}
572
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200573/* fails if orig_node has no router */
Sven Eckelmann56303d32012-06-05 22:31:31 +0200574static int batadv_write_buffer_text(struct batadv_priv *bat_priv,
575 struct seq_file *seq,
576 const struct batadv_gw_node *gw_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000577{
Sven Eckelmann56303d32012-06-05 22:31:31 +0200578 struct batadv_gw_node *curr_gw;
579 struct batadv_neigh_node *router;
Simon Wunderlich89652332013-11-13 19:14:46 +0100580 struct batadv_neigh_ifinfo *router_ifinfo = NULL;
Marek Lindner414254e2013-04-23 21:39:58 +0800581 int ret = -1;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000582
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100583 router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000584 if (!router)
585 goto out;
586
Simon Wunderlich89652332013-11-13 19:14:46 +0100587 router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
588 if (!router_ifinfo)
589 goto out;
590
Sven Eckelmann1409a832012-05-12 18:33:55 +0200591 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000592
Joe Perches6d911472015-02-16 17:31:39 -0800593 seq_printf(seq, "%s %pM (%3i) %pM [%10s]: %u.%u/%u.%u MBit\n",
594 (curr_gw == gw_node ? "=>" : " "),
595 gw_node->orig_node->orig,
596 router_ifinfo->bat_iv.tq_avg, router->addr,
597 router->if_incoming->net_dev->name,
598 gw_node->bandwidth_down / 10,
599 gw_node->bandwidth_down % 10,
600 gw_node->bandwidth_up / 10,
601 gw_node->bandwidth_up % 10);
Joe Perches92b83912015-02-22 13:47:56 -0800602 ret = seq_has_overflowed(seq) ? -1 : 0;
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000603
Marek Lindnerc4aac1a2011-03-23 11:24:34 +0100604 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200605 batadv_gw_node_free_ref(curr_gw);
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000606out:
Simon Wunderlich89652332013-11-13 19:14:46 +0100607 if (router_ifinfo)
608 batadv_neigh_ifinfo_free_ref(router_ifinfo);
609 if (router)
610 batadv_neigh_node_free_ref(router);
Linus Lüssing5d02b3c2011-02-13 21:13:02 +0000611 return ret;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000612}
613
Sven Eckelmann7cf06bc2012-05-12 02:09:29 +0200614int batadv_gw_client_seq_print_text(struct seq_file *seq, void *offset)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000615{
616 struct net_device *net_dev = (struct net_device *)seq->private;
Sven Eckelmann56303d32012-06-05 22:31:31 +0200617 struct batadv_priv *bat_priv = netdev_priv(net_dev);
618 struct batadv_hard_iface *primary_if;
619 struct batadv_gw_node *gw_node;
Marek Lindner30da63a2012-08-03 17:15:46 +0200620 int gw_count = 0;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000621
Marek Lindner30da63a2012-08-03 17:15:46 +0200622 primary_if = batadv_seq_print_text_primary_if_get(seq);
623 if (!primary_if)
Marek Lindner32ae9b22011-04-20 15:40:58 +0200624 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000625
Sven Eckelmann86ceb362012-03-07 09:07:45 +0100626 seq_printf(seq,
Marek Lindner414254e2013-04-23 21:39:58 +0800627 " %-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 +0200628 "Gateway", "#", BATADV_TQ_MAX_VALUE, "Nexthop", "outgoingIF",
629 BATADV_SOURCE_VERSION, primary_if->net_dev->name,
Marek Lindner32ae9b22011-04-20 15:40:58 +0200630 primary_if->net_dev->dev_addr, net_dev->name);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000631
632 rcu_read_lock();
Sasha Levinb67bfe02013-02-27 17:06:00 -0800633 hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
Linus Lüssinge1a5382f2011-03-14 22:43:37 +0000634 /* fails if orig_node has no router */
Sven Eckelmann1409a832012-05-12 18:33:55 +0200635 if (batadv_write_buffer_text(bat_priv, seq, gw_node) < 0)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000636 continue;
637
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000638 gw_count++;
639 }
640 rcu_read_unlock();
641
642 if (gw_count == 0)
Antonio Quartulli0c814652013-03-21 09:23:29 +0100643 seq_puts(seq, "No gateways in range ...\n");
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000644
Marek Lindner32ae9b22011-04-20 15:40:58 +0200645out:
646 if (primary_if)
Sven Eckelmanne5d89252012-05-12 13:48:54 +0200647 batadv_hardif_free_ref(primary_if);
Marek Lindner30da63a2012-08-03 17:15:46 +0200648 return 0;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000649}
650
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100651/**
652 * batadv_gw_dhcp_recipient_get - check if a packet is a DHCP message
653 * @skb: the packet to check
654 * @header_len: a pointer to the batman-adv header size
655 * @chaddr: buffer where the client address will be stored. Valid
656 * only if the function returns BATADV_DHCP_TO_CLIENT
657 *
658 * Returns:
659 * - BATADV_DHCP_NO if the packet is not a dhcp message or if there was an error
660 * while parsing it
661 * - BATADV_DHCP_TO_SERVER if this is a message going to the DHCP server
662 * - BATADV_DHCP_TO_CLIENT if this is a message going to a DHCP client
663 *
664 * This function may re-allocate the data buffer of the skb passed as argument.
665 */
666enum batadv_dhcp_recipient
667batadv_gw_dhcp_recipient_get(struct sk_buff *skb, unsigned int *header_len,
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200668 u8 *chaddr)
Antonio Quartulli43676ab2011-04-26 21:31:45 +0200669{
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100670 enum batadv_dhcp_recipient ret = BATADV_DHCP_NO;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000671 struct ethhdr *ethhdr;
672 struct iphdr *iphdr;
673 struct ipv6hdr *ipv6hdr;
674 struct udphdr *udphdr;
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200675 struct vlan_ethhdr *vhdr;
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100676 int chaddr_offset;
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200677 __be16 proto;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200678 u8 *p;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000679
680 /* check for ethernet header */
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200681 if (!pskb_may_pull(skb, *header_len + ETH_HLEN))
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100682 return BATADV_DHCP_NO;
683
Linus Lüssing927c2ed2014-01-19 22:22:45 +0100684 ethhdr = eth_hdr(skb);
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200685 proto = ethhdr->h_proto;
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200686 *header_len += ETH_HLEN;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000687
688 /* check for initial vlan header */
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200689 if (proto == htons(ETH_P_8021Q)) {
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200690 if (!pskb_may_pull(skb, *header_len + VLAN_HLEN))
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100691 return BATADV_DHCP_NO;
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200692
Linus Lüssing927c2ed2014-01-19 22:22:45 +0100693 vhdr = vlan_eth_hdr(skb);
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200694 proto = vhdr->h_vlan_encapsulated_proto;
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200695 *header_len += VLAN_HLEN;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000696 }
697
698 /* check for ip header */
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200699 switch (proto) {
700 case htons(ETH_P_IP):
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200701 if (!pskb_may_pull(skb, *header_len + sizeof(*iphdr)))
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100702 return BATADV_DHCP_NO;
703
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200704 iphdr = (struct iphdr *)(skb->data + *header_len);
705 *header_len += iphdr->ihl * 4;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000706
707 /* check for udp header */
708 if (iphdr->protocol != IPPROTO_UDP)
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100709 return BATADV_DHCP_NO;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000710
711 break;
Antonio Quartullif7f8ed52013-05-12 21:51:15 +0200712 case htons(ETH_P_IPV6):
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200713 if (!pskb_may_pull(skb, *header_len + sizeof(*ipv6hdr)))
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100714 return BATADV_DHCP_NO;
715
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200716 ipv6hdr = (struct ipv6hdr *)(skb->data + *header_len);
717 *header_len += sizeof(*ipv6hdr);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000718
719 /* check for udp header */
720 if (ipv6hdr->nexthdr != IPPROTO_UDP)
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100721 return BATADV_DHCP_NO;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000722
723 break;
724 default:
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100725 return BATADV_DHCP_NO;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000726 }
727
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200728 if (!pskb_may_pull(skb, *header_len + sizeof(*udphdr)))
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100729 return BATADV_DHCP_NO;
Linus Lüssing9d2c9482013-08-06 20:21:15 +0200730
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200731 udphdr = (struct udphdr *)(skb->data + *header_len);
732 *header_len += sizeof(*udphdr);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000733
734 /* check for bootp port */
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100735 switch (proto) {
736 case htons(ETH_P_IP):
737 if (udphdr->dest == htons(67))
738 ret = BATADV_DHCP_TO_SERVER;
739 else if (udphdr->source == htons(67))
740 ret = BATADV_DHCP_TO_CLIENT;
741 break;
742 case htons(ETH_P_IPV6):
743 if (udphdr->dest == htons(547))
744 ret = BATADV_DHCP_TO_SERVER;
745 else if (udphdr->source == htons(547))
746 ret = BATADV_DHCP_TO_CLIENT;
747 break;
748 }
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000749
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100750 chaddr_offset = *header_len + BATADV_DHCP_CHADDR_OFFSET;
751 /* store the client address if the message is going to a client */
752 if (ret == BATADV_DHCP_TO_CLIENT &&
753 pskb_may_pull(skb, chaddr_offset + ETH_ALEN)) {
754 /* check if the DHCP packet carries an Ethernet DHCP */
755 p = skb->data + *header_len + BATADV_DHCP_HTYPE_OFFSET;
756 if (*p != BATADV_DHCP_HTYPE_ETHERNET)
757 return BATADV_DHCP_NO;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000758
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100759 /* check if the DHCP packet carries a valid Ethernet address */
760 p = skb->data + *header_len + BATADV_DHCP_HLEN_OFFSET;
761 if (*p != ETH_ALEN)
762 return BATADV_DHCP_NO;
763
Antonio Quartulli8fdd0152014-01-22 00:42:11 +0100764 ether_addr_copy(chaddr, skb->data + chaddr_offset);
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100765 }
766
767 return ret;
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200768}
Antonio Quartulliaa143d22014-09-01 14:37:27 +0200769
Antonio Quartullibbb877e2013-06-04 12:11:42 +0200770/**
771 * batadv_gw_out_of_range - check if the dhcp request destination is the best gw
772 * @bat_priv: the bat priv with all the soft interface information
773 * @skb: the outgoing packet
774 *
775 * Check if the skb is a DHCP request and if it is sent to the current best GW
776 * server. Due to topology changes it may be the case that the GW server
777 * previously selected is not the best one anymore.
778 *
779 * Returns true if the packet destination is unicast and it is not the best gw,
780 * false otherwise.
781 *
782 * This call might reallocate skb data.
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100783 * Must be invoked only when the DHCP packet is going TO a DHCP SERVER.
Antonio Quartullibbb877e2013-06-04 12:11:42 +0200784 */
Sven Eckelmann56303d32012-06-05 22:31:31 +0200785bool batadv_gw_out_of_range(struct batadv_priv *bat_priv,
Linus Lüssing9d2c9482013-08-06 20:21:15 +0200786 struct sk_buff *skb)
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200787{
Sven Eckelmann4f248cf2015-06-09 20:50:49 +0200788 struct batadv_neigh_node *neigh_curr = NULL;
789 struct batadv_neigh_node *neigh_old = NULL;
Sven Eckelmann56303d32012-06-05 22:31:31 +0200790 struct batadv_orig_node *orig_dst_node = NULL;
Sven Eckelmann4f248cf2015-06-09 20:50:49 +0200791 struct batadv_gw_node *gw_node = NULL;
792 struct batadv_gw_node *curr_gw = NULL;
Simon Wunderlich89652332013-11-13 19:14:46 +0100793 struct batadv_neigh_ifinfo *curr_ifinfo, *old_ifinfo;
Antonio Quartulli6c413b12013-11-05 19:31:08 +0100794 struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
795 bool out_of_range = false;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200796 u8 curr_tq_avg;
Antonio Quartullibbb877e2013-06-04 12:11:42 +0200797 unsigned short vid;
798
799 vid = batadv_get_vid(skb, 0);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000800
Sven Eckelmann08c36d32012-05-12 02:09:39 +0200801 orig_dst_node = batadv_transtable_search(bat_priv, ethhdr->h_source,
Antonio Quartullibbb877e2013-06-04 12:11:42 +0200802 ethhdr->h_dest, vid);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200803 if (!orig_dst_node)
804 goto out;
805
Marek Lindner414254e2013-04-23 21:39:58 +0800806 gw_node = batadv_gw_node_get(bat_priv, orig_dst_node);
Antonio Quartulli0d164492014-12-20 13:48:57 +0100807 if (!gw_node)
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200808 goto out;
809
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200810 switch (atomic_read(&bat_priv->gw_mode)) {
Sven Eckelmanncd646ab2012-06-03 22:19:18 +0200811 case BATADV_GW_MODE_SERVER:
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200812 /* If we are a GW then we are our best GW. We can artificially
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200813 * set the tq towards ourself as the maximum value
814 */
Sven Eckelmann42d0b042012-06-03 22:19:17 +0200815 curr_tq_avg = BATADV_TQ_MAX_VALUE;
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200816 break;
Sven Eckelmanncd646ab2012-06-03 22:19:18 +0200817 case BATADV_GW_MODE_CLIENT:
Sven Eckelmann1409a832012-05-12 18:33:55 +0200818 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200819 if (!curr_gw)
820 goto out;
821
822 /* packet is going to our gateway */
823 if (curr_gw->orig_node == orig_dst_node)
824 goto out;
825
826 /* If the dhcp packet has been sent to a different gw,
827 * we have to evaluate whether the old gw is still
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200828 * reliable enough
829 */
Sven Eckelmann30d3c512012-05-12 02:09:36 +0200830 neigh_curr = batadv_find_router(bat_priv, curr_gw->orig_node,
831 NULL);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200832 if (!neigh_curr)
833 goto out;
834
Simon Wunderlich89652332013-11-13 19:14:46 +0100835 curr_ifinfo = batadv_neigh_ifinfo_get(neigh_curr,
836 BATADV_IF_DEFAULT);
837 if (!curr_ifinfo)
838 goto out;
839
840 curr_tq_avg = curr_ifinfo->bat_iv.tq_avg;
841 batadv_neigh_ifinfo_free_ref(curr_ifinfo);
842
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200843 break;
Sven Eckelmanncd646ab2012-06-03 22:19:18 +0200844 case BATADV_GW_MODE_OFF:
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200845 default:
846 goto out;
Antonio Quartulli43676ab2011-04-26 21:31:45 +0200847 }
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200848
Sven Eckelmann30d3c512012-05-12 02:09:36 +0200849 neigh_old = batadv_find_router(bat_priv, orig_dst_node, NULL);
Dan Carpenter2ef04f42011-11-29 09:09:09 +0300850 if (!neigh_old)
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200851 goto out;
852
Simon Wunderlich89652332013-11-13 19:14:46 +0100853 old_ifinfo = batadv_neigh_ifinfo_get(neigh_old, BATADV_IF_DEFAULT);
854 if (!old_ifinfo)
855 goto out;
856
857 if ((curr_tq_avg - old_ifinfo->bat_iv.tq_avg) > BATADV_GW_THRESHOLD)
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200858 out_of_range = true;
Simon Wunderlich89652332013-11-13 19:14:46 +0100859 batadv_neigh_ifinfo_free_ref(old_ifinfo);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200860
861out:
862 if (orig_dst_node)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200863 batadv_orig_node_free_ref(orig_dst_node);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200864 if (curr_gw)
Sven Eckelmann1409a832012-05-12 18:33:55 +0200865 batadv_gw_node_free_ref(curr_gw);
Marek Lindner414254e2013-04-23 21:39:58 +0800866 if (gw_node)
867 batadv_gw_node_free_ref(gw_node);
Antonio Quartulli43676ab2011-04-26 21:31:45 +0200868 if (neigh_old)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200869 batadv_neigh_node_free_ref(neigh_old);
Antonio Quartulli43676ab2011-04-26 21:31:45 +0200870 if (neigh_curr)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200871 batadv_neigh_node_free_ref(neigh_curr);
Marek Lindnerbe7af5c2011-09-08 13:12:53 +0200872 return out_of_range;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000873}