net/batman-adv/unicast.h

   1 /* Copyright (C) 2010-2012 B.A.T.M.A.N. contributors:
   2  *
   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
  18  */
  19
  20 #ifndef _NET_BATMAN_ADV_UNICAST_H_
  21 #define _NET_BATMAN_ADV_UNICAST_H_
  22
  23 #include "packet.h"
  24
  25 #define FRAG_TIMEOUT 10000      /* purge frag list entries after time in ms */
  26 #define FRAG_BUFFER_SIZE 6      /* number of list elements in buffer */
  27
  28 int batadv_frag_reassemble_skb(struct sk_buff *skb, struct bat_priv *bat_priv,
  29                                struct sk_buff **new_skb);
  30 void batadv_frag_list_free(struct list_head *head);
  31 int batadv_unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv);
  32 int batadv_frag_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv,
  33                          struct hard_iface *hard_iface,
  34                          const uint8_t dstaddr[]);
  35
  36 static inline int frag_can_reassemble(const struct sk_buff *skb, int mtu)
  37 {
  38         const struct unicast_frag_packet *unicast_packet;
  39         int uneven_correction = 0;
  40         unsigned int merged_size;
  41
  42         unicast_packet = (struct unicast_frag_packet *)skb->data;
  43
  44         if (unicast_packet->flags & UNI_FRAG_LARGETAIL) {
  45                 if (unicast_packet->flags & UNI_FRAG_HEAD)
  46                         uneven_correction = 1;
  47                 else
  48                         uneven_correction = -1;
  49         }
  50
  51         merged_size = (skb->len - sizeof(*unicast_packet)) * 2;
  52         merged_size += sizeof(struct unicast_packet) + uneven_correction;
  53
  54         return merged_size <= mtu;
  55 }
  56
  57 #endif /* _NET_BATMAN_ADV_UNICAST_H_ */