linux/net/batman-adv/packet.h
Antonio Quartulli cc47f66e6b batman-adv: improved roaming mechanism
With the current client announcement implementation, in case of roaming,
an update is triggered on the new AP serving the client. At that point
the new information is spread around by means of the OGM broadcasting
mechanism. Until this operations is not executed, no node is able to
correctly route traffic towards the client. This obviously causes packet
drops and introduces a delay in the time needed by the client to recover
its connections.

A new packet type called ROAMING_ADVERTISEMENT is added to account this
issue.

This message is sent in case of roaming from the new AP serving the
client to the old one and will contain the client MAC address. In this
way an out-of-OGM update is immediately committed, so that the old node
can update its global translation table. Traffic reaching this node will
then be redirected to the correct destination utilising the fresher
information. Thus reducing the packet drops and the connection recovery
delay.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-06-20 11:37:27 +02:00

214 lines
5.1 KiB
C

/*
* Copyright (C) 2007-2011 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, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA
*
*/
#ifndef _NET_BATMAN_ADV_PACKET_H_
#define _NET_BATMAN_ADV_PACKET_H_
#define ETH_P_BATMAN 0x4305 /* unofficial/not registered Ethertype */
enum bat_packettype {
BAT_PACKET = 0x01,
BAT_ICMP = 0x02,
BAT_UNICAST = 0x03,
BAT_BCAST = 0x04,
BAT_VIS = 0x05,
BAT_UNICAST_FRAG = 0x06,
BAT_TT_QUERY = 0x07,
BAT_ROAM_ADV = 0x08
};
/* this file is included by batctl which needs these defines */
#define COMPAT_VERSION 14
enum batman_flags {
PRIMARIES_FIRST_HOP = 1 << 4,
VIS_SERVER = 1 << 5,
DIRECTLINK = 1 << 6
};
/* ICMP message types */
enum icmp_packettype {
ECHO_REPLY = 0,
DESTINATION_UNREACHABLE = 3,
ECHO_REQUEST = 8,
TTL_EXCEEDED = 11,
PARAMETER_PROBLEM = 12
};
/* vis defines */
enum vis_packettype {
VIS_TYPE_SERVER_SYNC = 0,
VIS_TYPE_CLIENT_UPDATE = 1
};
/* fragmentation defines */
enum unicast_frag_flags {
UNI_FRAG_HEAD = 1 << 0,
UNI_FRAG_LARGETAIL = 1 << 1
};
/* TT_QUERY subtypes */
#define TT_QUERY_TYPE_MASK 0x3
enum tt_query_packettype {
TT_REQUEST = 0,
TT_RESPONSE = 1
};
/* TT_QUERY flags */
enum tt_query_flags {
TT_FULL_TABLE = 1 << 2
};
/* TT_CHANGE flags */
enum tt_change_flags {
TT_CHANGE_DEL = 0x01,
TT_CLIENT_ROAM = 0x02
};
struct batman_packet {
uint8_t packet_type;
uint8_t version; /* batman version field */
uint8_t ttl;
uint8_t flags; /* 0x40: DIRECTLINK flag, 0x20 VIS_SERVER flag... */
uint32_t seqno;
uint8_t orig[6];
uint8_t prev_sender[6];
uint8_t gw_flags; /* flags related to gateway class */
uint8_t tq;
uint8_t tt_num_changes;
uint8_t ttvn; /* translation table version number */
uint16_t tt_crc;
} __packed;
#define BAT_PACKET_LEN sizeof(struct batman_packet)
struct icmp_packet {
uint8_t packet_type;
uint8_t version; /* batman version field */
uint8_t ttl;
uint8_t msg_type; /* see ICMP message types above */
uint8_t dst[6];
uint8_t orig[6];
uint16_t seqno;
uint8_t uid;
uint8_t reserved;
} __packed;
#define BAT_RR_LEN 16
/* icmp_packet_rr must start with all fields from imcp_packet
* as this is assumed by code that handles ICMP packets */
struct icmp_packet_rr {
uint8_t packet_type;
uint8_t version; /* batman version field */
uint8_t ttl;
uint8_t msg_type; /* see ICMP message types above */
uint8_t dst[6];
uint8_t orig[6];
uint16_t seqno;
uint8_t uid;
uint8_t rr_cur;
uint8_t rr[BAT_RR_LEN][ETH_ALEN];
} __packed;
struct unicast_packet {
uint8_t packet_type;
uint8_t version; /* batman version field */
uint8_t ttl;
uint8_t ttvn; /* destination translation table version number */
uint8_t dest[6];
} __packed;
struct unicast_frag_packet {
uint8_t packet_type;
uint8_t version; /* batman version field */
uint8_t ttl;
uint8_t ttvn; /* destination translation table version number */
uint8_t dest[6];
uint8_t flags;
uint8_t align;
uint8_t orig[6];
uint16_t seqno;
} __packed;
struct bcast_packet {
uint8_t packet_type;
uint8_t version; /* batman version field */
uint8_t ttl;
uint8_t reserved;
uint32_t seqno;
uint8_t orig[6];
} __packed;
struct vis_packet {
uint8_t packet_type;
uint8_t version; /* batman version field */
uint8_t ttl; /* TTL */
uint8_t vis_type; /* which type of vis-participant sent this? */
uint32_t seqno; /* sequence number */
uint8_t entries; /* number of entries behind this struct */
uint8_t reserved;
uint8_t vis_orig[6]; /* originator that announces its neighbors */
uint8_t target_orig[6]; /* who should receive this packet */
uint8_t sender_orig[6]; /* who sent or rebroadcasted this packet */
} __packed;
struct tt_query_packet {
uint8_t packet_type;
uint8_t version; /* batman version field */
uint8_t ttl;
/* the flag field is a combination of:
* - TT_REQUEST or TT_RESPONSE
* - TT_FULL_TABLE */
uint8_t flags;
uint8_t dst[ETH_ALEN];
uint8_t src[ETH_ALEN];
/* the ttvn field is:
* if TT_REQUEST: ttvn that triggered the
* request
* if TT_RESPONSE: new ttvn for the src
* orig_node */
uint8_t ttvn;
/* tt_data field is:
* if TT_REQUEST: crc associated with the
* ttvn
* if TT_RESPONSE: table_size */
uint16_t tt_data;
} __packed;
struct roam_adv_packet {
uint8_t packet_type;
uint8_t version;
uint8_t ttl;
uint8_t reserved;
uint8_t dst[ETH_ALEN];
uint8_t src[ETH_ALEN];
uint8_t client[ETH_ALEN];
} __packed;
struct tt_change {
uint8_t flags;
uint8_t addr[ETH_ALEN];
} __packed;
#endif /* _NET_BATMAN_ADV_PACKET_H_ */