1 /*
2  * Copyright (C) 2010-2012 B.A.T.M.A.N. contributors:
3  *
4  * Andreas Langer
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of version 2 of the GNU General Public
8  * License as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  * General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
18  * 02110-1301, USA
19  *
20  */
21 
22 #ifndef _NET_BATMAN_ADV_UNICAST_H_
23 #define _NET_BATMAN_ADV_UNICAST_H_
24 
25 #include "packet.h"
26 
27 #define FRAG_TIMEOUT 10000	/* purge frag list entries after time in ms */
28 #define FRAG_BUFFER_SIZE 6	/* number of list elements in buffer */
29 
30 int frag_reassemble_skb(struct sk_buff *skb, struct bat_priv *bat_priv,
31 			struct sk_buff **new_skb);
32 void frag_list_free(struct list_head *head);
33 int unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv);
34 int frag_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv,
35 		  struct hard_iface *hard_iface, const uint8_t dstaddr[]);
36 
frag_can_reassemble(const struct sk_buff * skb,int mtu)37 static inline int frag_can_reassemble(const struct sk_buff *skb, int mtu)
38 {
39 	const struct unicast_frag_packet *unicast_packet;
40 	int uneven_correction = 0;
41 	unsigned int merged_size;
42 
43 	unicast_packet = (struct unicast_frag_packet *)skb->data;
44 
45 	if (unicast_packet->flags & UNI_FRAG_LARGETAIL) {
46 		if (unicast_packet->flags & UNI_FRAG_HEAD)
47 			uneven_correction = 1;
48 		else
49 			uneven_correction = -1;
50 	}
51 
52 	merged_size = (skb->len - sizeof(*unicast_packet)) * 2;
53 	merged_size += sizeof(struct unicast_packet) + uneven_correction;
54 
55 	return merged_size <= mtu;
56 }
57 
58 #endif /* _NET_BATMAN_ADV_UNICAST_H_ */
59