/*

 OLSR MDNS plugin.

 Written by Saverio Proto <zioproto@gmail.com> and Claudio Pisa <clauz@ninux.org>.

     This file is part of OLSR MDNS PLUGIN.

     The OLSR MDNS PLUGIN is free software: you can redistribute it and/or modify

     it under the terms of the GNU General Public License as published by

     the Free Software Foundation, either version 3 of the License, or

     (at your option) any later version.

     The OLSR MDNS PLUGIN is distributed in the hope that it will be useful,

     but WITHOUT ANY WARRANTY; without even the implied warranty of

     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

     GNU General Public License for more details.

     You should have received a copy of the GNU General Public License

     along with Foobar.  If not, see <http://www.gnu.org/licenses/>.

  */

 #ifndef _MDNS_PACKET_H

 #define _MDNS_PACKET_H

 /* System includes */

 #include <net/if.h> /* IFNAMSIZ, IFHWADDRLEN */

 #include <sys/types.h> /* u_int8_t, u_int16_t */

 /* BMF-encapsulated packets are Ethernet-IP-UDP packets, which start

  * with a 8-bytes BMF header (struct TEncapHeader), followed by the

  * encapsulated Ethernet-IP packet itself */

 struct TEncapHeader

 {

   /* Use a standard Type-Length-Value (TLV) element */

   u_int8_t type;

   u_int8_t len;

   u_int16_t reserved; /* Always 0 */

   u_int32_t crc32;

 } __attribute__((__packed__));

 #define ENCAP_HDR_LEN ((int)sizeof(struct TEncapHeader))

 #define BMF_ENCAP_TYPE 1

 #define BMF_ENCAP_LEN 6

 struct TSaveTtl

 {

   u_int8_t ttl;

   u_int16_t check;

 } __attribute__((__packed__));

 int IsIpFragment(unsigned char* ipPacket);

 u_int16_t GetIpTotalLength(unsigned char* ipPacket);

 unsigned int GetIpHeaderLength(unsigned char* ipPacket);

 u_int8_t GetTtl(unsigned char* ipPacket);

 void SaveTtlAndChecksum(unsigned char* ipPacket, struct TSaveTtl* sttl);

 void RestoreTtlAndChecksum(unsigned char* ipPacket, struct TSaveTtl* sttl);

 void DecreaseTtlAndUpdateHeaderChecksum(unsigned char* ipPacket);

 struct ip* GetIpHeader(unsigned char* encapsulationUdpData);

 unsigned char* GetIpPacket(unsigned char* encapsulationUdpData);

 #endif /* _MDNS_PACKET_H */