blob: d021055ad26224c347e8d8e9eb02e5119a965eb3 [file] [log] [blame]
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +02001/* Copyright (C) 2010-2012 B.A.T.M.A.N. contributors:
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +00002 *
3 * Andreas Langer
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
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17 * 02110-1301, USA
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000018 */
19
20#include "main.h"
21#include "unicast.h"
22#include "send.h"
23#include "soft-interface.h"
24#include "gateway_client.h"
25#include "originator.h"
26#include "hash.h"
27#include "translation-table.h"
28#include "routing.h"
29#include "hard-interface.h"
30
31
32static struct sk_buff *frag_merge_packet(struct list_head *head,
33 struct frag_packet_list_entry *tfp,
34 struct sk_buff *skb)
35{
36 struct unicast_frag_packet *up =
37 (struct unicast_frag_packet *)skb->data;
38 struct sk_buff *tmp_skb;
39 struct unicast_packet *unicast_packet;
Sven Eckelmann704509b2011-05-14 23:14:54 +020040 int hdr_len = sizeof(*unicast_packet);
41 int uni_diff = sizeof(*up) - hdr_len;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000042
43 /* set skb to the first part and tmp_skb to the second part */
44 if (up->flags & UNI_FRAG_HEAD) {
45 tmp_skb = tfp->skb;
46 } else {
47 tmp_skb = skb;
48 skb = tfp->skb;
49 }
50
Sven Eckelmann531c9da2011-02-06 23:26:43 +000051 if (skb_linearize(skb) < 0 || skb_linearize(tmp_skb) < 0)
52 goto err;
53
Sven Eckelmann704509b2011-05-14 23:14:54 +020054 skb_pull(tmp_skb, sizeof(*up));
Sven Eckelmann531c9da2011-02-06 23:26:43 +000055 if (pskb_expand_head(skb, 0, tmp_skb->len, GFP_ATOMIC) < 0)
56 goto err;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000057
58 /* move free entry to end */
59 tfp->skb = NULL;
60 tfp->seqno = 0;
61 list_move_tail(&tfp->list, head);
62
63 memcpy(skb_put(skb, tmp_skb->len), tmp_skb->data, tmp_skb->len);
64 kfree_skb(tmp_skb);
65
66 memmove(skb->data + uni_diff, skb->data, hdr_len);
Sven Eckelmann40e0c4f2012-03-07 09:07:48 +010067 unicast_packet = (struct unicast_packet *)skb_pull(skb, uni_diff);
Sven Eckelmann76543d12011-11-20 15:47:38 +010068 unicast_packet->header.packet_type = BAT_UNICAST;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000069
70 return skb;
Sven Eckelmann531c9da2011-02-06 23:26:43 +000071
72err:
73 /* free buffered skb, skb will be freed later */
74 kfree_skb(tfp->skb);
75 return NULL;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +000076}
77
78static void frag_create_entry(struct list_head *head, struct sk_buff *skb)
79{
80 struct frag_packet_list_entry *tfp;
81 struct unicast_frag_packet *up =
82 (struct unicast_frag_packet *)skb->data;
83
84 /* free and oldest packets stand at the end */
85 tfp = list_entry((head)->prev, typeof(*tfp), list);
86 kfree_skb(tfp->skb);
87
88 tfp->seqno = ntohs(up->seqno);
89 tfp->skb = skb;
90 list_move(&tfp->list, head);
91 return;
92}
93
94static int frag_create_buffer(struct list_head *head)
95{
96 int i;
97 struct frag_packet_list_entry *tfp;
98
99 for (i = 0; i < FRAG_BUFFER_SIZE; i++) {
Sven Eckelmann704509b2011-05-14 23:14:54 +0200100 tfp = kmalloc(sizeof(*tfp), GFP_ATOMIC);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000101 if (!tfp) {
Sven Eckelmann88ed1e772012-05-12 02:09:40 +0200102 batadv_frag_list_free(head);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000103 return -ENOMEM;
104 }
105 tfp->skb = NULL;
106 tfp->seqno = 0;
107 INIT_LIST_HEAD(&tfp->list);
108 list_add(&tfp->list, head);
109 }
110
111 return 0;
112}
113
114static struct frag_packet_list_entry *frag_search_packet(struct list_head *head,
Sven Eckelmann747e4222011-05-14 23:14:50 +0200115 const struct unicast_frag_packet *up)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000116{
117 struct frag_packet_list_entry *tfp;
118 struct unicast_frag_packet *tmp_up = NULL;
119 uint16_t search_seqno;
120
121 if (up->flags & UNI_FRAG_HEAD)
122 search_seqno = ntohs(up->seqno)+1;
123 else
124 search_seqno = ntohs(up->seqno)-1;
125
126 list_for_each_entry(tfp, head, list) {
127
128 if (!tfp->skb)
129 continue;
130
131 if (tfp->seqno == ntohs(up->seqno))
132 goto mov_tail;
133
134 tmp_up = (struct unicast_frag_packet *)tfp->skb->data;
135
136 if (tfp->seqno == search_seqno) {
137
138 if ((tmp_up->flags & UNI_FRAG_HEAD) !=
139 (up->flags & UNI_FRAG_HEAD))
140 return tfp;
141 else
142 goto mov_tail;
143 }
144 }
145 return NULL;
146
147mov_tail:
148 list_move_tail(&tfp->list, head);
149 return NULL;
150}
151
Sven Eckelmann88ed1e772012-05-12 02:09:40 +0200152void batadv_frag_list_free(struct list_head *head)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000153{
154 struct frag_packet_list_entry *pf, *tmp_pf;
155
156 if (!list_empty(head)) {
157
158 list_for_each_entry_safe(pf, tmp_pf, head, list) {
159 kfree_skb(pf->skb);
160 list_del(&pf->list);
161 kfree(pf);
162 }
163 }
164 return;
165}
166
167/* frag_reassemble_skb():
168 * returns NET_RX_DROP if the operation failed - skb is left intact
169 * returns NET_RX_SUCCESS if the fragment was buffered (skb_new will be NULL)
170 * or the skb could be reassembled (skb_new will point to the new packet and
171 * skb was freed)
172 */
Sven Eckelmann88ed1e772012-05-12 02:09:40 +0200173int batadv_frag_reassemble_skb(struct sk_buff *skb, struct bat_priv *bat_priv,
174 struct sk_buff **new_skb)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000175{
176 struct orig_node *orig_node;
177 struct frag_packet_list_entry *tmp_frag_entry;
178 int ret = NET_RX_DROP;
179 struct unicast_frag_packet *unicast_packet =
180 (struct unicast_frag_packet *)skb->data;
181
182 *new_skb = NULL;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000183
Sven Eckelmannda641192012-05-12 13:48:56 +0200184 orig_node = batadv_orig_hash_find(bat_priv, unicast_packet->orig);
Marek Lindner7aadf882011-02-18 12:28:09 +0000185 if (!orig_node)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000186 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000187
188 orig_node->last_frag_packet = jiffies;
189
190 if (list_empty(&orig_node->frag_list) &&
191 frag_create_buffer(&orig_node->frag_list)) {
192 pr_debug("couldn't create frag buffer\n");
193 goto out;
194 }
195
196 tmp_frag_entry = frag_search_packet(&orig_node->frag_list,
197 unicast_packet);
198
199 if (!tmp_frag_entry) {
200 frag_create_entry(&orig_node->frag_list, skb);
201 ret = NET_RX_SUCCESS;
202 goto out;
203 }
204
205 *new_skb = frag_merge_packet(&orig_node->frag_list, tmp_frag_entry,
206 skb);
207 /* if not, merge failed */
208 if (*new_skb)
209 ret = NET_RX_SUCCESS;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000210
Marek Lindner7aadf882011-02-18 12:28:09 +0000211out:
212 if (orig_node)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200213 batadv_orig_node_free_ref(orig_node);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000214 return ret;
215}
216
Sven Eckelmann88ed1e772012-05-12 02:09:40 +0200217int batadv_frag_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv,
218 struct hard_iface *hard_iface, const uint8_t dstaddr[])
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000219{
220 struct unicast_packet tmp_uc, *unicast_packet;
Marek Lindner32ae9b22011-04-20 15:40:58 +0200221 struct hard_iface *primary_if;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000222 struct sk_buff *frag_skb;
223 struct unicast_frag_packet *frag1, *frag2;
Sven Eckelmann704509b2011-05-14 23:14:54 +0200224 int uc_hdr_len = sizeof(*unicast_packet);
225 int ucf_hdr_len = sizeof(*frag1);
Sven Eckelmann5c77d8b2011-01-25 21:59:26 +0000226 int data_len = skb->len - uc_hdr_len;
Marek Lindner32ae9b22011-04-20 15:40:58 +0200227 int large_tail = 0, ret = NET_RX_DROP;
Sven Eckelmannc2f7f0e2011-02-10 14:33:56 +0000228 uint16_t seqno;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000229
Sven Eckelmanne5d89252012-05-12 13:48:54 +0200230 primary_if = batadv_primary_if_get_selected(bat_priv);
Marek Lindner32ae9b22011-04-20 15:40:58 +0200231 if (!primary_if)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000232 goto dropped;
233
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000234 frag_skb = dev_alloc_skb(data_len - (data_len / 2) + ucf_hdr_len);
Jesper Juhled7809d2011-01-13 21:53:38 +0100235 if (!frag_skb)
236 goto dropped;
Sven Eckelmann5c77d8b2011-01-25 21:59:26 +0000237 skb_reserve(frag_skb, ucf_hdr_len);
Jesper Juhled7809d2011-01-13 21:53:38 +0100238
Sven Eckelmann40e0c4f2012-03-07 09:07:48 +0100239 unicast_packet = (struct unicast_packet *)skb->data;
Jesper Juhled7809d2011-01-13 21:53:38 +0100240 memcpy(&tmp_uc, unicast_packet, uc_hdr_len);
Sven Eckelmann5c77d8b2011-01-25 21:59:26 +0000241 skb_split(skb, frag_skb, data_len / 2 + uc_hdr_len);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000242
Sven Eckelmann04b482a2012-05-12 02:09:38 +0200243 if (batadv_skb_head_push(skb, ucf_hdr_len - uc_hdr_len) < 0 ||
244 batadv_skb_head_push(frag_skb, ucf_hdr_len) < 0)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000245 goto drop_frag;
246
247 frag1 = (struct unicast_frag_packet *)skb->data;
248 frag2 = (struct unicast_frag_packet *)frag_skb->data;
249
Sven Eckelmann704509b2011-05-14 23:14:54 +0200250 memcpy(frag1, &tmp_uc, sizeof(tmp_uc));
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000251
Sven Eckelmann76543d12011-11-20 15:47:38 +0100252 frag1->header.ttl--;
253 frag1->header.version = COMPAT_VERSION;
254 frag1->header.packet_type = BAT_UNICAST_FRAG;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000255
Marek Lindner32ae9b22011-04-20 15:40:58 +0200256 memcpy(frag1->orig, primary_if->net_dev->dev_addr, ETH_ALEN);
Sven Eckelmann704509b2011-05-14 23:14:54 +0200257 memcpy(frag2, frag1, sizeof(*frag2));
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000258
Sven Eckelmannae361ce2011-01-25 22:02:31 +0000259 if (data_len & 1)
260 large_tail = UNI_FRAG_LARGETAIL;
261
262 frag1->flags = UNI_FRAG_HEAD | large_tail;
263 frag2->flags = large_tail;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000264
Marek Lindnere6c10f42011-02-18 12:33:20 +0000265 seqno = atomic_add_return(2, &hard_iface->frag_seqno);
Sven Eckelmannc2f7f0e2011-02-10 14:33:56 +0000266 frag1->seqno = htons(seqno - 1);
267 frag2->seqno = htons(seqno);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000268
Sven Eckelmann9455e342012-05-12 02:09:37 +0200269 batadv_send_skb_packet(skb, hard_iface, dstaddr);
270 batadv_send_skb_packet(frag_skb, hard_iface, dstaddr);
Marek Lindner32ae9b22011-04-20 15:40:58 +0200271 ret = NET_RX_SUCCESS;
272 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000273
274drop_frag:
275 kfree_skb(frag_skb);
276dropped:
277 kfree_skb(skb);
Marek Lindner32ae9b22011-04-20 15:40:58 +0200278out:
279 if (primary_if)
Sven Eckelmanne5d89252012-05-12 13:48:54 +0200280 batadv_hardif_free_ref(primary_if);
Marek Lindner32ae9b22011-04-20 15:40:58 +0200281 return ret;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000282}
283
Sven Eckelmann88ed1e772012-05-12 02:09:40 +0200284int batadv_unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv)
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000285{
286 struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
287 struct unicast_packet *unicast_packet;
Marek Lindner7b36e8e2011-02-18 12:28:10 +0000288 struct orig_node *orig_node;
Marek Lindner44524fc2011-02-10 14:33:53 +0000289 struct neigh_node *neigh_node;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000290 int data_len = skb->len;
Marek Lindner44524fc2011-02-10 14:33:53 +0000291 int ret = 1;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000292
293 /* get routing information */
Linus Lüssing43c70ad2011-02-13 21:13:04 +0000294 if (is_multicast_ether_addr(ethhdr->h_dest)) {
Sven Eckelmann7cf06bc2012-05-12 02:09:29 +0200295 orig_node = batadv_gw_get_selected_orig(bat_priv);
Linus Lüssing43c70ad2011-02-13 21:13:04 +0000296 if (orig_node)
Marek Lindner44524fc2011-02-10 14:33:53 +0000297 goto find_router;
298 }
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000299
Antonio Quartulli3d393e42011-07-07 15:35:37 +0200300 /* check for tt host - increases orig_node refcount.
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200301 * returns NULL in case of AP isolation
302 */
Sven Eckelmann08c36d32012-05-12 02:09:39 +0200303 orig_node = batadv_transtable_search(bat_priv, ethhdr->h_source,
304 ethhdr->h_dest);
Marek Lindner44524fc2011-02-10 14:33:53 +0000305find_router:
Sven Eckelmann9cfc7bd2012-05-12 02:09:43 +0200306 /* find_router():
Marek Lindnerd0072602011-01-19 20:01:44 +0000307 * - if orig_node is NULL it returns NULL
308 * - increases neigh_nodes refcount if found.
309 */
Sven Eckelmann30d3c512012-05-12 02:09:36 +0200310 neigh_node = batadv_find_router(bat_priv, orig_node, NULL);
Marek Lindner44524fc2011-02-10 14:33:53 +0000311 if (!neigh_node)
Marek Lindnerd0072602011-01-19 20:01:44 +0000312 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000313
Sven Eckelmann04b482a2012-05-12 02:09:38 +0200314 if (batadv_skb_head_push(skb, sizeof(*unicast_packet)) < 0)
Marek Lindnerd0072602011-01-19 20:01:44 +0000315 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000316
317 unicast_packet = (struct unicast_packet *)skb->data;
318
Sven Eckelmann76543d12011-11-20 15:47:38 +0100319 unicast_packet->header.version = COMPAT_VERSION;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000320 /* batman packet type: unicast */
Sven Eckelmann76543d12011-11-20 15:47:38 +0100321 unicast_packet->header.packet_type = BAT_UNICAST;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000322 /* set unicast ttl */
Sven Eckelmann76543d12011-11-20 15:47:38 +0100323 unicast_packet->header.ttl = TTL;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000324 /* copy the destination for faster routing */
325 memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN);
Antonio Quartullia73105b2011-04-27 14:27:44 +0200326 /* set the destination tt version number */
327 unicast_packet->ttvn =
328 (uint8_t)atomic_read(&orig_node->last_ttvn);
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000329
Antonio Quartulli3275e7c2012-03-16 18:03:28 +0100330 /* inform the destination node that we are still missing a correct route
331 * for this client. The destination will receive this packet and will
332 * try to reroute it because the ttvn contained in the header is less
333 * than the current one
334 */
Sven Eckelmann08c36d32012-05-12 02:09:39 +0200335 if (batadv_tt_global_client_is_roaming(bat_priv, ethhdr->h_dest))
Antonio Quartulli3275e7c2012-03-16 18:03:28 +0100336 unicast_packet->ttvn = unicast_packet->ttvn - 1;
337
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000338 if (atomic_read(&bat_priv->fragmentation) &&
Sven Eckelmann704509b2011-05-14 23:14:54 +0200339 data_len + sizeof(*unicast_packet) >
Marek Lindnerd0072602011-01-19 20:01:44 +0000340 neigh_node->if_incoming->net_dev->mtu) {
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000341 /* send frag skb decreases ttl */
Sven Eckelmann76543d12011-11-20 15:47:38 +0100342 unicast_packet->header.ttl++;
Sven Eckelmann88ed1e772012-05-12 02:09:40 +0200343 ret = batadv_frag_send_skb(skb, bat_priv,
344 neigh_node->if_incoming,
345 neigh_node->addr);
Marek Lindner44524fc2011-02-10 14:33:53 +0000346 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000347 }
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000348
Sven Eckelmann9455e342012-05-12 02:09:37 +0200349 batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
Marek Lindner44524fc2011-02-10 14:33:53 +0000350 ret = 0;
351 goto out;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000352
Marek Lindner44524fc2011-02-10 14:33:53 +0000353out:
354 if (neigh_node)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200355 batadv_neigh_node_free_ref(neigh_node);
Marek Lindner44524fc2011-02-10 14:33:53 +0000356 if (orig_node)
Sven Eckelmann7d211ef2012-05-12 02:09:34 +0200357 batadv_orig_node_free_ref(orig_node);
Marek Lindner44524fc2011-02-10 14:33:53 +0000358 if (ret == 1)
359 kfree_skb(skb);
360 return ret;
Sven Eckelmannc6c8fea2010-12-13 11:19:28 +0000361}