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 frag_packet_list_entry *tfp,
37 struct unicast_frag_packet *up =
38 (struct unicast_frag_packet *)skb->data;
39 struct sk_buff *tmp_skb;
40 struct unicast_packet *unicast_packet;
41 int hdr_len = sizeof(*unicast_packet);
42 int uni_diff = sizeof(*up) - hdr_len;
44 /* set skb to the first part and tmp_skb to the second part */
45 if (up->flags & 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 unicast_packet *)skb_pull(skb, uni_diff);
69 unicast_packet->header.packet_type = BAT_UNICAST;
74 /* free buffered skb, skb will be freed later */
79 static void batadv_frag_create_entry(struct list_head *head,
82 struct frag_packet_list_entry *tfp;
83 struct unicast_frag_packet *up =
84 (struct unicast_frag_packet *)skb->data;
86 /* free and oldest packets stand at the end */
87 tfp = list_entry((head)->prev, typeof(*tfp), list);
90 tfp->seqno = ntohs(up->seqno);
92 list_move(&tfp->list, head);
96 static int batadv_frag_create_buffer(struct list_head *head)
99 struct frag_packet_list_entry *tfp;
101 for (i = 0; i < BATADV_FRAG_BUFFER_SIZE; i++) {
102 tfp = kmalloc(sizeof(*tfp), GFP_ATOMIC);
104 batadv_frag_list_free(head);
109 INIT_LIST_HEAD(&tfp->list);
110 list_add(&tfp->list, head);
116 static struct frag_packet_list_entry *
117 batadv_frag_search_packet(struct list_head *head,
118 const struct unicast_frag_packet *up)
120 struct frag_packet_list_entry *tfp;
121 struct unicast_frag_packet *tmp_up = NULL;
122 uint16_t search_seqno;
124 if (up->flags & UNI_FRAG_HEAD)
125 search_seqno = ntohs(up->seqno)+1;
127 search_seqno = ntohs(up->seqno)-1;
129 list_for_each_entry(tfp, head, list) {
134 if (tfp->seqno == ntohs(up->seqno))
137 tmp_up = (struct unicast_frag_packet *)tfp->skb->data;
139 if (tfp->seqno == search_seqno) {
141 if ((tmp_up->flags & UNI_FRAG_HEAD) !=
142 (up->flags & UNI_FRAG_HEAD))
151 list_move_tail(&tfp->list, head);
155 void batadv_frag_list_free(struct list_head *head)
157 struct frag_packet_list_entry *pf, *tmp_pf;
159 if (!list_empty(head)) {
161 list_for_each_entry_safe(pf, tmp_pf, head, list) {
170 /* frag_reassemble_skb():
171 * returns NET_RX_DROP if the operation failed - skb is left intact
172 * returns NET_RX_SUCCESS if the fragment was buffered (skb_new will be NULL)
173 * or the skb could be reassembled (skb_new will point to the new packet and
176 int batadv_frag_reassemble_skb(struct sk_buff *skb, struct bat_priv *bat_priv,
177 struct sk_buff **new_skb)
179 struct orig_node *orig_node;
180 struct frag_packet_list_entry *tmp_frag_entry;
181 int ret = NET_RX_DROP;
182 struct unicast_frag_packet *unicast_packet =
183 (struct unicast_frag_packet *)skb->data;
187 orig_node = batadv_orig_hash_find(bat_priv, unicast_packet->orig);
191 orig_node->last_frag_packet = jiffies;
193 if (list_empty(&orig_node->frag_list) &&
194 batadv_frag_create_buffer(&orig_node->frag_list)) {
195 pr_debug("couldn't create frag buffer\n");
199 tmp_frag_entry = batadv_frag_search_packet(&orig_node->frag_list,
202 if (!tmp_frag_entry) {
203 batadv_frag_create_entry(&orig_node->frag_list, skb);
204 ret = NET_RX_SUCCESS;
208 *new_skb = batadv_frag_merge_packet(&orig_node->frag_list,
209 tmp_frag_entry, skb);
210 /* if not, merge failed */
212 ret = NET_RX_SUCCESS;
216 batadv_orig_node_free_ref(orig_node);
220 int batadv_frag_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv,
221 struct hard_iface *hard_iface, const uint8_t dstaddr[])
223 struct unicast_packet tmp_uc, *unicast_packet;
224 struct hard_iface *primary_if;
225 struct sk_buff *frag_skb;
226 struct unicast_frag_packet *frag1, *frag2;
227 int uc_hdr_len = sizeof(*unicast_packet);
228 int ucf_hdr_len = sizeof(*frag1);
229 int data_len = skb->len - uc_hdr_len;
230 int large_tail = 0, ret = NET_RX_DROP;
233 primary_if = batadv_primary_if_get_selected(bat_priv);
237 frag_skb = dev_alloc_skb(data_len - (data_len / 2) + ucf_hdr_len);
240 skb_reserve(frag_skb, ucf_hdr_len);
242 unicast_packet = (struct unicast_packet *)skb->data;
243 memcpy(&tmp_uc, unicast_packet, uc_hdr_len);
244 skb_split(skb, frag_skb, data_len / 2 + uc_hdr_len);
246 if (batadv_skb_head_push(skb, ucf_hdr_len - uc_hdr_len) < 0 ||
247 batadv_skb_head_push(frag_skb, ucf_hdr_len) < 0)
250 frag1 = (struct unicast_frag_packet *)skb->data;
251 frag2 = (struct unicast_frag_packet *)frag_skb->data;
253 memcpy(frag1, &tmp_uc, sizeof(tmp_uc));
256 frag1->header.version = BATADV_COMPAT_VERSION;
257 frag1->header.packet_type = BAT_UNICAST_FRAG;
259 memcpy(frag1->orig, primary_if->net_dev->dev_addr, ETH_ALEN);
260 memcpy(frag2, frag1, sizeof(*frag2));
263 large_tail = UNI_FRAG_LARGETAIL;
265 frag1->flags = UNI_FRAG_HEAD | large_tail;
266 frag2->flags = large_tail;
268 seqno = atomic_add_return(2, &hard_iface->frag_seqno);
269 frag1->seqno = htons(seqno - 1);
270 frag2->seqno = htons(seqno);
272 batadv_send_skb_packet(skb, hard_iface, dstaddr);
273 batadv_send_skb_packet(frag_skb, hard_iface, dstaddr);
274 ret = NET_RX_SUCCESS;
283 batadv_hardif_free_ref(primary_if);
287 int batadv_unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv)
289 struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
290 struct unicast_packet *unicast_packet;
291 struct orig_node *orig_node;
292 struct neigh_node *neigh_node;
293 int data_len = skb->len;
296 /* get routing information */
297 if (is_multicast_ether_addr(ethhdr->h_dest)) {
298 orig_node = batadv_gw_get_selected_orig(bat_priv);
303 /* check for tt host - increases orig_node refcount.
304 * returns NULL in case of AP isolation
306 orig_node = batadv_transtable_search(bat_priv, ethhdr->h_source,
310 * - if orig_node is NULL it returns NULL
311 * - increases neigh_nodes refcount if found.
313 neigh_node = batadv_find_router(bat_priv, orig_node, NULL);
317 if (batadv_skb_head_push(skb, sizeof(*unicast_packet)) < 0)
320 unicast_packet = (struct unicast_packet *)skb->data;
322 unicast_packet->header.version = BATADV_COMPAT_VERSION;
323 /* batman packet type: unicast */
324 unicast_packet->header.packet_type = BAT_UNICAST;
325 /* set unicast ttl */
326 unicast_packet->header.ttl = BATADV_TTL;
327 /* copy the destination for faster routing */
328 memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN);
329 /* set the destination tt version number */
330 unicast_packet->ttvn =
331 (uint8_t)atomic_read(&orig_node->last_ttvn);
333 /* inform the destination node that we are still missing a correct route
334 * for this client. The destination will receive this packet and will
335 * try to reroute it because the ttvn contained in the header is less
336 * than the current one
338 if (batadv_tt_global_client_is_roaming(bat_priv, ethhdr->h_dest))
339 unicast_packet->ttvn = unicast_packet->ttvn - 1;
341 if (atomic_read(&bat_priv->fragmentation) &&
342 data_len + sizeof(*unicast_packet) >
343 neigh_node->if_incoming->net_dev->mtu) {
344 /* send frag skb decreases ttl */
345 unicast_packet->header.ttl++;
346 ret = batadv_frag_send_skb(skb, bat_priv,
347 neigh_node->if_incoming,
352 batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
358 batadv_neigh_node_free_ref(neigh_node);
360 batadv_orig_node_free_ref(orig_node);