1 /* Copyright (C) 2010-2012 B.A.T.M.A.N. contributors:
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.
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.
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
23 #include "soft-interface.h"
24 #include "gateway_client.h"
25 #include "originator.h"
27 #include "translation-table.h"
29 #include "hard-interface.h"
32 static struct sk_buff
*
33 batadv_frag_merge_packet(struct list_head
*head
,
34 struct batadv_frag_packet_list_entry
*tfp
,
37 struct batadv_unicast_frag_packet
*up
;
38 struct sk_buff
*tmp_skb
;
39 struct batadv_unicast_packet
*unicast_packet
;
40 int hdr_len
= sizeof(*unicast_packet
);
41 int uni_diff
= sizeof(*up
) - hdr_len
;
43 up
= (struct batadv_unicast_frag_packet
*)skb
->data
;
44 /* set skb to the first part and tmp_skb to the second part */
45 if (up
->flags
& BATADV_UNI_FRAG_HEAD
) {
52 if (skb_linearize(skb
) < 0 || skb_linearize(tmp_skb
) < 0)
55 skb_pull(tmp_skb
, sizeof(*up
));
56 if (pskb_expand_head(skb
, 0, tmp_skb
->len
, GFP_ATOMIC
) < 0)
59 /* move free entry to end */
62 list_move_tail(&tfp
->list
, head
);
64 memcpy(skb_put(skb
, tmp_skb
->len
), tmp_skb
->data
, tmp_skb
->len
);
67 memmove(skb
->data
+ uni_diff
, skb
->data
, hdr_len
);
68 unicast_packet
= (struct batadv_unicast_packet
*)skb_pull(skb
,
70 unicast_packet
->header
.packet_type
= BATADV_UNICAST
;
75 /* free buffered skb, skb will be freed later */
80 static void batadv_frag_create_entry(struct list_head
*head
,
83 struct batadv_frag_packet_list_entry
*tfp
;
84 struct batadv_unicast_frag_packet
*up
;
86 up
= (struct batadv_unicast_frag_packet
*)skb
->data
;
88 /* free and oldest packets stand at the end */
89 tfp
= list_entry((head
)->prev
, typeof(*tfp
), list
);
92 tfp
->seqno
= ntohs(up
->seqno
);
94 list_move(&tfp
->list
, head
);
98 static int batadv_frag_create_buffer(struct list_head
*head
)
101 struct batadv_frag_packet_list_entry
*tfp
;
103 for (i
= 0; i
< BATADV_FRAG_BUFFER_SIZE
; i
++) {
104 tfp
= kmalloc(sizeof(*tfp
), GFP_ATOMIC
);
106 batadv_frag_list_free(head
);
111 INIT_LIST_HEAD(&tfp
->list
);
112 list_add(&tfp
->list
, head
);
118 static struct batadv_frag_packet_list_entry
*
119 batadv_frag_search_packet(struct list_head
*head
,
120 const struct batadv_unicast_frag_packet
*up
)
122 struct batadv_frag_packet_list_entry
*tfp
;
123 struct batadv_unicast_frag_packet
*tmp_up
= NULL
;
124 uint16_t search_seqno
;
126 if (up
->flags
& BATADV_UNI_FRAG_HEAD
)
127 search_seqno
= ntohs(up
->seqno
)+1;
129 search_seqno
= ntohs(up
->seqno
)-1;
131 list_for_each_entry(tfp
, head
, list
) {
136 if (tfp
->seqno
== ntohs(up
->seqno
))
139 tmp_up
= (struct batadv_unicast_frag_packet
*)tfp
->skb
->data
;
141 if (tfp
->seqno
== search_seqno
) {
143 if ((tmp_up
->flags
& BATADV_UNI_FRAG_HEAD
) !=
144 (up
->flags
& BATADV_UNI_FRAG_HEAD
))
153 list_move_tail(&tfp
->list
, head
);
157 void batadv_frag_list_free(struct list_head
*head
)
159 struct batadv_frag_packet_list_entry
*pf
, *tmp_pf
;
161 if (!list_empty(head
)) {
163 list_for_each_entry_safe(pf
, tmp_pf
, head
, list
) {
172 /* frag_reassemble_skb():
173 * returns NET_RX_DROP if the operation failed - skb is left intact
174 * returns NET_RX_SUCCESS if the fragment was buffered (skb_new will be NULL)
175 * or the skb could be reassembled (skb_new will point to the new packet and
178 int batadv_frag_reassemble_skb(struct sk_buff
*skb
,
179 struct batadv_priv
*bat_priv
,
180 struct sk_buff
**new_skb
)
182 struct batadv_orig_node
*orig_node
;
183 struct batadv_frag_packet_list_entry
*tmp_frag_entry
;
184 int ret
= NET_RX_DROP
;
185 struct batadv_unicast_frag_packet
*unicast_packet
;
187 unicast_packet
= (struct batadv_unicast_frag_packet
*)skb
->data
;
190 orig_node
= batadv_orig_hash_find(bat_priv
, unicast_packet
->orig
);
194 orig_node
->last_frag_packet
= jiffies
;
196 if (list_empty(&orig_node
->frag_list
) &&
197 batadv_frag_create_buffer(&orig_node
->frag_list
)) {
198 pr_debug("couldn't create frag buffer\n");
202 tmp_frag_entry
= batadv_frag_search_packet(&orig_node
->frag_list
,
205 if (!tmp_frag_entry
) {
206 batadv_frag_create_entry(&orig_node
->frag_list
, skb
);
207 ret
= NET_RX_SUCCESS
;
211 *new_skb
= batadv_frag_merge_packet(&orig_node
->frag_list
,
212 tmp_frag_entry
, skb
);
213 /* if not, merge failed */
215 ret
= NET_RX_SUCCESS
;
219 batadv_orig_node_free_ref(orig_node
);
223 int batadv_frag_send_skb(struct sk_buff
*skb
, struct batadv_priv
*bat_priv
,
224 struct batadv_hard_iface
*hard_iface
,
225 const uint8_t dstaddr
[])
227 struct batadv_unicast_packet tmp_uc
, *unicast_packet
;
228 struct batadv_hard_iface
*primary_if
;
229 struct sk_buff
*frag_skb
;
230 struct batadv_unicast_frag_packet
*frag1
, *frag2
;
231 int uc_hdr_len
= sizeof(*unicast_packet
);
232 int ucf_hdr_len
= sizeof(*frag1
);
233 int data_len
= skb
->len
- uc_hdr_len
;
234 int large_tail
= 0, ret
= NET_RX_DROP
;
237 primary_if
= batadv_primary_if_get_selected(bat_priv
);
241 frag_skb
= dev_alloc_skb(data_len
- (data_len
/ 2) + ucf_hdr_len
);
244 skb_reserve(frag_skb
, ucf_hdr_len
);
246 unicast_packet
= (struct batadv_unicast_packet
*)skb
->data
;
247 memcpy(&tmp_uc
, unicast_packet
, uc_hdr_len
);
248 skb_split(skb
, frag_skb
, data_len
/ 2 + uc_hdr_len
);
250 if (batadv_skb_head_push(skb
, ucf_hdr_len
- uc_hdr_len
) < 0 ||
251 batadv_skb_head_push(frag_skb
, ucf_hdr_len
) < 0)
254 frag1
= (struct batadv_unicast_frag_packet
*)skb
->data
;
255 frag2
= (struct batadv_unicast_frag_packet
*)frag_skb
->data
;
257 memcpy(frag1
, &tmp_uc
, sizeof(tmp_uc
));
260 frag1
->header
.version
= BATADV_COMPAT_VERSION
;
261 frag1
->header
.packet_type
= BATADV_UNICAST_FRAG
;
263 memcpy(frag1
->orig
, primary_if
->net_dev
->dev_addr
, ETH_ALEN
);
264 memcpy(frag2
, frag1
, sizeof(*frag2
));
267 large_tail
= BATADV_UNI_FRAG_LARGETAIL
;
269 frag1
->flags
= BATADV_UNI_FRAG_HEAD
| large_tail
;
270 frag2
->flags
= large_tail
;
272 seqno
= atomic_add_return(2, &hard_iface
->frag_seqno
);
273 frag1
->seqno
= htons(seqno
- 1);
274 frag2
->seqno
= htons(seqno
);
276 batadv_send_skb_packet(skb
, hard_iface
, dstaddr
);
277 batadv_send_skb_packet(frag_skb
, hard_iface
, dstaddr
);
278 ret
= NET_RX_SUCCESS
;
287 batadv_hardif_free_ref(primary_if
);
291 int batadv_unicast_send_skb(struct sk_buff
*skb
, struct batadv_priv
*bat_priv
)
293 struct ethhdr
*ethhdr
= (struct ethhdr
*)skb
->data
;
294 struct batadv_unicast_packet
*unicast_packet
;
295 struct batadv_orig_node
*orig_node
;
296 struct batadv_neigh_node
*neigh_node
;
297 int data_len
= skb
->len
;
299 unsigned int dev_mtu
;
301 /* get routing information */
302 if (is_multicast_ether_addr(ethhdr
->h_dest
)) {
303 orig_node
= batadv_gw_get_selected_orig(bat_priv
);
308 /* check for tt host - increases orig_node refcount.
309 * returns NULL in case of AP isolation
311 orig_node
= batadv_transtable_search(bat_priv
, ethhdr
->h_source
,
316 * - if orig_node is NULL it returns NULL
317 * - increases neigh_nodes refcount if found.
319 neigh_node
= batadv_find_router(bat_priv
, orig_node
, NULL
);
324 if (batadv_skb_head_push(skb
, sizeof(*unicast_packet
)) < 0)
327 unicast_packet
= (struct batadv_unicast_packet
*)skb
->data
;
329 unicast_packet
->header
.version
= BATADV_COMPAT_VERSION
;
330 /* batman packet type: unicast */
331 unicast_packet
->header
.packet_type
= BATADV_UNICAST
;
332 /* set unicast ttl */
333 unicast_packet
->header
.ttl
= BATADV_TTL
;
334 /* copy the destination for faster routing */
335 memcpy(unicast_packet
->dest
, orig_node
->orig
, ETH_ALEN
);
336 /* set the destination tt version number */
337 unicast_packet
->ttvn
=
338 (uint8_t)atomic_read(&orig_node
->last_ttvn
);
340 /* inform the destination node that we are still missing a correct route
341 * for this client. The destination will receive this packet and will
342 * try to reroute it because the ttvn contained in the header is less
343 * than the current one
345 if (batadv_tt_global_client_is_roaming(bat_priv
, ethhdr
->h_dest
))
346 unicast_packet
->ttvn
= unicast_packet
->ttvn
- 1;
348 dev_mtu
= neigh_node
->if_incoming
->net_dev
->mtu
;
349 if (atomic_read(&bat_priv
->fragmentation
) &&
350 data_len
+ sizeof(*unicast_packet
) > dev_mtu
) {
351 /* send frag skb decreases ttl */
352 unicast_packet
->header
.ttl
++;
353 ret
= batadv_frag_send_skb(skb
, bat_priv
,
354 neigh_node
->if_incoming
,
359 batadv_send_skb_packet(skb
, neigh_node
->if_incoming
, neigh_node
->addr
);
365 batadv_neigh_node_free_ref(neigh_node
);
367 batadv_orig_node_free_ref(orig_node
);