/* Copyright (C) 2007-2014 B.A.T.M.A.N. contributors:
   *
   * Marek Lindner, Simon Wunderlich
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of version 2 of the GNU General Public
   * License as published by the Free Software Foundation.
   *
   * This program 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 this program; if not, see <http://www.gnu.org/licenses/>.
   */
  
  #ifndef _NET_BATMAN_ADV_PACKET_H_
  #define _NET_BATMAN_ADV_PACKET_H_
  
  /**
   * enum batadv_packettype - types for batman-adv encapsulated packets
   * @BATADV_IV_OGM: originator messages for B.A.T.M.A.N. IV
   * @BATADV_BCAST: broadcast packets carrying broadcast payload
   * @BATADV_CODED: network coded packets
   *
   * @BATADV_UNICAST: unicast packets carrying unicast payload traffic
   * @BATADV_UNICAST_FRAG: unicast packets carrying a fragment of the original
   *     payload packet
   * @BATADV_UNICAST_4ADDR: unicast packet including the originator address of
   *     the sender
   * @BATADV_ICMP: unicast packet like IP ICMP used for ping or traceroute
   * @BATADV_UNICAST_TVLV: unicast packet carrying TVLV containers
   */
  enum batadv_packettype {
  	/* 0x00 - 0x3f: local packets or special rules for handling */
  	BATADV_IV_OGM           = 0x00,
  	BATADV_BCAST            = 0x01,
  	BATADV_CODED            = 0x02,
  	/* 0x40 - 0x7f: unicast */
  #define BATADV_UNICAST_MIN     0x40
  	BATADV_UNICAST          = 0x40,
  	BATADV_UNICAST_FRAG     = 0x41,
  	BATADV_UNICAST_4ADDR    = 0x42,
  	BATADV_ICMP             = 0x43,
  	BATADV_UNICAST_TVLV     = 0x44,
  #define BATADV_UNICAST_MAX     0x7f
  	/* 0x80 - 0xff: reserved */
  };
  
  /**
   * enum batadv_subtype - packet subtype for unicast4addr
   * @BATADV_P_DATA: user payload
   * @BATADV_P_DAT_DHT_GET: DHT request message
   * @BATADV_P_DAT_DHT_PUT: DHT store message
   * @BATADV_P_DAT_CACHE_REPLY: ARP reply generated by DAT
   */
  enum batadv_subtype {
  	BATADV_P_DATA			= 0x01,
  	BATADV_P_DAT_DHT_GET		= 0x02,
  	BATADV_P_DAT_DHT_PUT		= 0x03,
  	BATADV_P_DAT_CACHE_REPLY	= 0x04,
  };
  
  /* this file is included by batctl which needs these defines */
  #define BATADV_COMPAT_VERSION 15
  
  /**
   * enum batadv_iv_flags - flags used in B.A.T.M.A.N. IV OGM packets
   * @BATADV_NOT_BEST_NEXT_HOP: flag is set when ogm packet is forwarded and was
   *     previously received from someone else than the best neighbor.
   * @BATADV_PRIMARIES_FIRST_HOP: flag is set when the primary interface address
   *     is used, and the packet travels its first hop.
   * @BATADV_DIRECTLINK: flag is for the first hop or if rebroadcasted from a
   *     one hop neighbor on the interface where it was originally received.
   */
  enum batadv_iv_flags {
  	BATADV_NOT_BEST_NEXT_HOP   = BIT(0),
  	BATADV_PRIMARIES_FIRST_HOP = BIT(1),
  	BATADV_DIRECTLINK          = BIT(2),
  };
  
  /* ICMP message types */
  enum batadv_icmp_packettype {
  	BATADV_ECHO_REPLY	       = 0,
  	BATADV_DESTINATION_UNREACHABLE = 3,
  	BATADV_ECHO_REQUEST	       = 8,
  	BATADV_TTL_EXCEEDED	       = 11,
  	BATADV_PARAMETER_PROBLEM       = 12,
  };
  
  /* tt data subtypes */
  #define BATADV_TT_DATA_TYPE_MASK 0x0F
  
  /**
   * enum batadv_tt_data_flags - flags for tt data tvlv
   * @BATADV_TT_OGM_DIFF: TT diff propagated through OGM
   * @BATADV_TT_REQUEST: TT request message
   * @BATADV_TT_RESPONSE: TT response message
   * @BATADV_TT_FULL_TABLE: contains full table to replace existing table
   */
  enum batadv_tt_data_flags {
  	BATADV_TT_OGM_DIFF   = BIT(0),
  	BATADV_TT_REQUEST    = BIT(1),
  	BATADV_TT_RESPONSE   = BIT(2),
  	BATADV_TT_FULL_TABLE = BIT(4),
  };
  
  /* BATADV_TT_CLIENT flags.
   * Flags from BIT(0) to BIT(7) are sent on the wire, while flags from BIT(8) to
   * BIT(15) are used for local computation only.
   * Flags from BIT(4) to BIT(7) are kept in sync with the rest of the network.
   */
  enum batadv_tt_client_flags {
  	BATADV_TT_CLIENT_DEL     = BIT(0),
  	BATADV_TT_CLIENT_ROAM    = BIT(1),
  	BATADV_TT_CLIENT_WIFI    = BIT(4),
  	BATADV_TT_CLIENT_ISOLA	 = BIT(5),
  	BATADV_TT_CLIENT_NOPURGE = BIT(8),
  	BATADV_TT_CLIENT_NEW     = BIT(9),
  	BATADV_TT_CLIENT_PENDING = BIT(10),
  	BATADV_TT_CLIENT_TEMP	 = BIT(11),
  };
  
  /**
   * batadv_vlan_flags - flags for the four MSB of any vlan ID field
   * @BATADV_VLAN_HAS_TAG: whether the field contains a valid vlan tag or not
   */
  enum batadv_vlan_flags {
  	BATADV_VLAN_HAS_TAG	= BIT(15),
  };
  
  /* claim frame types for the bridge loop avoidance */
  enum batadv_bla_claimframe {
  	BATADV_CLAIM_TYPE_CLAIM		= 0x00,
  	BATADV_CLAIM_TYPE_UNCLAIM	= 0x01,
  	BATADV_CLAIM_TYPE_ANNOUNCE	= 0x02,
  	BATADV_CLAIM_TYPE_REQUEST	= 0x03,
  };
  
  /**
   * enum batadv_tvlv_type - tvlv type definitions
   * @BATADV_TVLV_GW: gateway tvlv
   * @BATADV_TVLV_DAT: distributed arp table tvlv
   * @BATADV_TVLV_NC: network coding tvlv
   * @BATADV_TVLV_TT: translation table tvlv
   * @BATADV_TVLV_ROAM: roaming advertisement tvlv
   */
  enum batadv_tvlv_type {
  	BATADV_TVLV_GW		= 0x01,
  	BATADV_TVLV_DAT		= 0x02,
  	BATADV_TVLV_NC		= 0x03,
  	BATADV_TVLV_TT		= 0x04,
  	BATADV_TVLV_ROAM	= 0x05,
  };
  
  #pragma pack(2)
  /* the destination hardware field in the ARP frame is used to
   * transport the claim type and the group id
   */
  struct batadv_bla_claim_dst {
  	uint8_t magic[3];	/* FF:43:05 */
  	uint8_t type;		/* bla_claimframe */
  	__be16 group;		/* group id */
  };
  #pragma pack()
  
  /**
   * struct batadv_ogm_packet - ogm (routing protocol) packet
   * @packet_type: batman-adv packet type, part of the general header
   * @version: batman-adv protocol version, part of the genereal header
   * @ttl: time to live for this packet, part of the genereal header
   * @flags: contains routing relevant flags - see enum batadv_iv_flags
   * @tvlv_len: length of tvlv data following the ogm header
   */
  struct batadv_ogm_packet {
  	uint8_t  packet_type;
  	uint8_t  version;
  	uint8_t  ttl;
  	uint8_t  flags;
  	__be32   seqno;
  	uint8_t  orig[ETH_ALEN];
  	uint8_t  prev_sender[ETH_ALEN];
  	uint8_t  reserved;
  	uint8_t  tq;
  	__be16   tvlv_len;
  	/* __packed is not needed as the struct size is divisible by 4,
  	 * and the largest data type in this struct has a size of 4.
  	 */
  };
  
  #define BATADV_OGM_HLEN sizeof(struct batadv_ogm_packet)
  
  /**
   * batadv_icmp_header - common members among all the ICMP packets
   * @packet_type: batman-adv packet type, part of the general header
   * @version: batman-adv protocol version, part of the genereal header
   * @ttl: time to live for this packet, part of the genereal header
   * @msg_type: ICMP packet type
   * @dst: address of the destination node
   * @orig: address of the source node
   * @uid: local ICMP socket identifier
   * @align: not used - useful for alignment purposes only
   *
   * This structure is used for ICMP packets parsing only and it is never sent
   * over the wire. The alignment field at the end is there to ensure that
   * members are padded the same way as they are in real packets.
   */
  struct batadv_icmp_header {
  	uint8_t  packet_type;
  	uint8_t  version;
  	uint8_t  ttl;
  	uint8_t  msg_type; /* see ICMP message types above */
  	uint8_t  dst[ETH_ALEN];
  	uint8_t  orig[ETH_ALEN];
  	uint8_t  uid;
  	uint8_t  align[3];
  };
  
  /**
   * batadv_icmp_packet - ICMP packet
   * @packet_type: batman-adv packet type, part of the general header
   * @version: batman-adv protocol version, part of the genereal header
   * @ttl: time to live for this packet, part of the genereal header
   * @msg_type: ICMP packet type
   * @dst: address of the destination node
   * @orig: address of the source node
   * @uid: local ICMP socket identifier
   * @reserved: not used - useful for alignment
   * @seqno: ICMP sequence number
   */
  struct batadv_icmp_packet {
  	uint8_t  packet_type;
  	uint8_t  version;
  	uint8_t  ttl;
  	uint8_t  msg_type; /* see ICMP message types above */
  	uint8_t  dst[ETH_ALEN];
  	uint8_t  orig[ETH_ALEN];
  	uint8_t  uid;
  	uint8_t  reserved;
  	__be16   seqno;
  };
  
  #define BATADV_RR_LEN 16
  
  /**
   * batadv_icmp_packet_rr - ICMP RouteRecord packet
   * @packet_type: batman-adv packet type, part of the general header
   * @version: batman-adv protocol version, part of the genereal header
   * @ttl: time to live for this packet, part of the genereal header
   * @msg_type: ICMP packet type
   * @dst: address of the destination node
   * @orig: address of the source node
   * @uid: local ICMP socket identifier
   * @rr_cur: number of entries the rr array
   * @seqno: ICMP sequence number
   * @rr: route record array
   */
  struct batadv_icmp_packet_rr {
  	uint8_t  packet_type;
  	uint8_t  version;
  	uint8_t  ttl;
  	uint8_t  msg_type; /* see ICMP message types above */
  	uint8_t  dst[ETH_ALEN];
  	uint8_t  orig[ETH_ALEN];
  	uint8_t  uid;
  	uint8_t  rr_cur;
  	__be16   seqno;
  	uint8_t  rr[BATADV_RR_LEN][ETH_ALEN];
  };
  
  #define BATADV_ICMP_MAX_PACKET_SIZE	sizeof(struct batadv_icmp_packet_rr)
  
  /* All packet headers in front of an ethernet header have to be completely
   * divisible by 2 but not by 4 to make the payload after the ethernet
   * header again 4 bytes boundary aligned.
   *
   * A packing of 2 is necessary to avoid extra padding at the end of the struct
   * caused by a structure member which is larger than two bytes. Otherwise
   * the structure would not fulfill the previously mentioned rule to avoid the
   * misalignment of the payload after the ethernet header. It may also lead to
   * leakage of information when the padding it not initialized before sending.
   */
  #pragma pack(2)
  
  /**
   * struct batadv_unicast_packet - unicast packet for network payload
   * @packet_type: batman-adv packet type, part of the general header
   * @version: batman-adv protocol version, part of the genereal header
   * @ttl: time to live for this packet, part of the genereal header
   * @ttvn: translation table version number
   * @dest: originator destination of the unicast packet
   */
  struct batadv_unicast_packet {
  	uint8_t  packet_type;
  	uint8_t  version;
  	uint8_t  ttl;
  	uint8_t  ttvn; /* destination translation table version number */
  	uint8_t  dest[ETH_ALEN];
  	/* "4 bytes boundary + 2 bytes" long to make the payload after the
  	 * following ethernet header again 4 bytes boundary aligned
  	 */
  };
  
  /**
   * struct batadv_unicast_4addr_packet - extended unicast packet
   * @u: common unicast packet header
   * @src: address of the source
   * @subtype: packet subtype
   */
  struct batadv_unicast_4addr_packet {
  	struct batadv_unicast_packet u;
  	uint8_t src[ETH_ALEN];
  	uint8_t subtype;
  	uint8_t reserved;
  	/* "4 bytes boundary + 2 bytes" long to make the payload after the
  	 * following ethernet header again 4 bytes boundary aligned
  	 */
  };
  
  /**
   * struct batadv_frag_packet - fragmented packet
   * @packet_type: batman-adv packet type, part of the general header
   * @version: batman-adv protocol version, part of the genereal header
   * @ttl: time to live for this packet, part of the genereal header
   * @dest: final destination used when routing fragments
   * @orig: originator of the fragment used when merging the packet
   * @no: fragment number within this sequence
   * @reserved: reserved byte for alignment
   * @seqno: sequence identification
   * @total_size: size of the merged packet
   */
  struct batadv_frag_packet {
  	uint8_t packet_type;
  	uint8_t version;  /* batman version field */
  	uint8_t ttl;
  #if defined(__BIG_ENDIAN_BITFIELD)
  	uint8_t no:4;
  	uint8_t reserved:4;
  #elif defined(__LITTLE_ENDIAN_BITFIELD)
  	uint8_t reserved:4;
  	uint8_t no:4;
  #else
  #error "unknown bitfield endianess"
  #endif
  	uint8_t dest[ETH_ALEN];
  	uint8_t orig[ETH_ALEN];
  	__be16  seqno;
  	__be16  total_size;
  };
  
  /**
   * struct batadv_bcast_packet - broadcast packet for network payload
   * @packet_type: batman-adv packet type, part of the general header
   * @version: batman-adv protocol version, part of the genereal header
   * @ttl: time to live for this packet, part of the genereal header
   * @reserved: reserved byte for alignment
   * @seqno: sequence identification
   * @orig: originator of the broadcast packet
   */
  struct batadv_bcast_packet {
  	uint8_t  packet_type;
  	uint8_t  version;  /* batman version field */
  	uint8_t  ttl;
  	uint8_t  reserved;
  	__be32   seqno;
  	uint8_t  orig[ETH_ALEN];
  	/* "4 bytes boundary + 2 bytes" long to make the payload after the
  	 * following ethernet header again 4 bytes boundary aligned
  	 */
  };
  
  /**
   * struct batadv_coded_packet - network coded packet
   * @packet_type: batman-adv packet type, part of the general header
   * @version: batman-adv protocol version, part of the genereal header
   * @ttl: time to live for this packet, part of the genereal header
   * @reserved: Align following fields to 2-byte boundaries
   * @first_source: original source of first included packet
   * @first_orig_dest: original destinal of first included packet
   * @first_crc: checksum of first included packet
   * @first_ttvn: tt-version number of first included packet
   * @second_ttl: ttl of second packet
   * @second_dest: second receiver of this coded packet
   * @second_source: original source of second included packet
   * @second_orig_dest: original destination of second included packet
   * @second_crc: checksum of second included packet
   * @second_ttvn: tt version number of second included packet
   * @coded_len: length of network coded part of the payload
   */
  struct batadv_coded_packet {
  	uint8_t  packet_type;
  	uint8_t  version;  /* batman version field */
  	uint8_t  ttl;
  	uint8_t  first_ttvn;
  	/* uint8_t  first_dest[ETH_ALEN]; - saved in mac header destination */
  	uint8_t  first_source[ETH_ALEN];
  	uint8_t  first_orig_dest[ETH_ALEN];
  	__be32   first_crc;
  	uint8_t  second_ttl;
  	uint8_t  second_ttvn;
  	uint8_t  second_dest[ETH_ALEN];
  	uint8_t  second_source[ETH_ALEN];
  	uint8_t  second_orig_dest[ETH_ALEN];
  	__be32   second_crc;
  	__be16   coded_len;
  };
  
  #pragma pack()
  
  /**
   * struct batadv_unicast_tvlv - generic unicast packet with tvlv payload
   * @packet_type: batman-adv packet type, part of the general header
   * @version: batman-adv protocol version, part of the genereal header
   * @ttl: time to live for this packet, part of the genereal header
   * @reserved: reserved field (for packet alignment)
   * @src: address of the source
   * @dst: address of the destination
   * @tvlv_len: length of tvlv data following the unicast tvlv header
   * @align: 2 bytes to align the header to a 4 byte boundry
   */
  struct batadv_unicast_tvlv_packet {
  	uint8_t  packet_type;
  	uint8_t  version;  /* batman version field */
  	uint8_t  ttl;
  	uint8_t  reserved;
  	uint8_t  dst[ETH_ALEN];
  	uint8_t  src[ETH_ALEN];
  	__be16   tvlv_len;
  	uint16_t align;
  };
  
  /**
   * struct batadv_tvlv_hdr - base tvlv header struct
   * @type: tvlv container type (see batadv_tvlv_type)
   * @version: tvlv container version
   * @len: tvlv container length
   */
  struct batadv_tvlv_hdr {
  	uint8_t type;
  	uint8_t version;
  	__be16  len;
  };
  
  /**
   * struct batadv_tvlv_gateway_data - gateway data propagated through gw tvlv
   *  container
   * @bandwidth_down: advertised uplink download bandwidth
   * @bandwidth_up: advertised uplink upload bandwidth
   */
  struct batadv_tvlv_gateway_data {
  	__be32 bandwidth_down;
  	__be32 bandwidth_up;
  };
  
  /**
   * struct batadv_tvlv_tt_data - tt data propagated through the tt tvlv container
   * @flags: translation table flags (see batadv_tt_data_flags)
   * @ttvn: translation table version number
   * @vlan_num: number of announced VLANs. In the TVLV this struct is followed by
   *  one batadv_tvlv_tt_vlan_data object per announced vlan
   */
  struct batadv_tvlv_tt_data {
  	uint8_t flags;
  	uint8_t ttvn;
  	__be16  num_vlan;
  };
  
  /**
   * struct batadv_tvlv_tt_vlan_data - vlan specific tt data propagated through
   *  the tt tvlv container
   * @crc: crc32 checksum of the entries belonging to this vlan
   * @vid: vlan identifier
   * @reserved: unused, useful for alignment purposes
   */
  struct batadv_tvlv_tt_vlan_data {
  	__be32	crc;
  	__be16	vid;
  	uint16_t reserved;
  };
  
  /**
   * struct batadv_tvlv_tt_change - translation table diff data
   * @flags: status indicators concerning the non-mesh client (see
   *  batadv_tt_client_flags)
   * @reserved: reserved field - useful for alignment purposes only
   * @addr: mac address of non-mesh client that triggered this tt change
   * @vid: VLAN identifier
   */
  struct batadv_tvlv_tt_change {
  	uint8_t flags;
  	uint8_t reserved[3];
  	uint8_t addr[ETH_ALEN];
  	__be16 vid;
  };
  
  /**
   * struct batadv_tvlv_roam_adv - roaming advertisement
   * @client: mac address of roaming client
   * @vid: VLAN identifier
   */
  struct batadv_tvlv_roam_adv {
  	uint8_t  client[ETH_ALEN];
  	__be16 vid;
  };
  
  #endif /* _NET_BATMAN_ADV_PACKET_H_ */