LXR linux/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 BATADV_FRAG_TIMEOUT 10000 /* purge frag list entries after time in ms */
  26#define BATADV_FRAG_BUFFER_SIZE 6 /* number of list elements in buffer */
  27
  28int batadv_frag_reassemble_skb(struct sk_buff *skb,
  29                               struct batadv_priv *bat_priv,
  30                               struct sk_buff **new_skb);
  31void batadv_frag_list_free(struct list_head *head);
  32int batadv_unicast_send_skb(struct sk_buff *skb, struct batadv_priv *bat_priv);
  33int batadv_frag_send_skb(struct sk_buff *skb, struct batadv_priv *bat_priv,
  34                         struct batadv_hard_iface *hard_iface,
  35                         const uint8_t dstaddr[]);
  36
  37static inline int batadv_frag_can_reassemble(const struct sk_buff *skb, int mtu)
  38{
  39        const struct batadv_unicast_frag_packet *unicast_packet;
  40        int uneven_correction = 0;
  41        unsigned int merged_size;
  42
  43        unicast_packet = (struct batadv_unicast_frag_packet *)skb->data;
  44
  45        if (unicast_packet->flags & BATADV_UNI_FRAG_LARGETAIL) {
  46                if (unicast_packet->flags & BATADV_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 batadv_unicast_packet) + uneven_correction;
  54
  55        return merged_size <= mtu;
  56}
  57
  58#endif /* _NET_BATMAN_ADV_UNICAST_H_ */
  59