ip_carp.h revision 211157 
1/*	$FreeBSD: head/sys/netinet/ip_carp.h 211157 2010-08-11 00:51:50Z will $	*/
2/*	$OpenBSD: ip_carp.h,v 1.8 2004/07/29 22:12:15 mcbride Exp $	*/
3
4/*
5 * Copyright (c) 2002 Michael Shalayeff. All rights reserved.
6 * Copyright (c) 2003 Ryan McBride. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR OR HIS RELATIVES BE LIABLE FOR ANY DIRECT,
21 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
23 * SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
25 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
26 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
27 * THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30#ifndef _IP_CARP_H
31#define	_IP_CARP_H
32
33/*
34 * The CARP header layout is as follows:
35 *
36 *     0                   1                   2                   3
37 *     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
38 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
39 *    |Version| Type  | VirtualHostID |    AdvSkew    |    Auth Len   |
40 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
41 *    |   Reserved    |     AdvBase   |          Checksum             |
42 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
43 *    |                         Counter (1)                           |
44 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
45 *    |                         Counter (2)                           |
46 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
47 *    |                        SHA-1 HMAC (1)                         |
48 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
49 *    |                        SHA-1 HMAC (2)                         |
50 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
51 *    |                        SHA-1 HMAC (3)                         |
52 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
53 *    |                        SHA-1 HMAC (4)                         |
54 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
55 *    |                        SHA-1 HMAC (5)                         |
56 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
57 *
58 */
59
60struct carp_header {
61#if BYTE_ORDER == LITTLE_ENDIAN
62	u_int8_t	carp_type:4,
63			carp_version:4;
64#endif
65#if BYTE_ORDER == BIG_ENDIAN
66	u_int8_t	carp_version:4,
67			carp_type:4;
68#endif
69	u_int8_t	carp_vhid;	/* virtual host id */
70	u_int8_t	carp_advskew;	/* advertisement skew */
71	u_int8_t	carp_authlen;   /* size of counter+md, 32bit chunks */
72	u_int8_t	carp_pad1;	/* reserved */
73	u_int8_t	carp_advbase;	/* advertisement interval */
74	u_int16_t	carp_cksum;
75	u_int32_t	carp_counter[2];
76	unsigned char	carp_md[20];	/* SHA1 HMAC */
77} __packed;
78
79#ifdef CTASSERT
80CTASSERT(sizeof(struct carp_header) == 36);
81#endif
82
83#define	CARP_DFLTTL		255
84
85/* carp_version */
86#define	CARP_VERSION		2
87
88/* carp_type */
89#define	CARP_ADVERTISEMENT	0x01
90
91#define	CARP_KEY_LEN		20	/* a sha1 hash of a passphrase */
92
93/* carp_advbase */
94#define	CARP_DFLTINTV		1
95
96/*
97 * Statistics.
98 */
99struct carpstats {
100	uint64_t	carps_ipackets;		/* total input packets, IPv4 */
101	uint64_t	carps_ipackets6;	/* total input packets, IPv6 */
102	uint64_t	carps_badif;		/* wrong interface */
103	uint64_t	carps_badttl;		/* TTL is not CARP_DFLTTL */
104	uint64_t	carps_hdrops;		/* packets shorter than hdr */
105	uint64_t	carps_badsum;		/* bad checksum */
106	uint64_t	carps_badver;		/* bad (incl unsupp) version */
107	uint64_t	carps_badlen;		/* data length does not match */
108	uint64_t	carps_badauth;		/* bad authentication */
109	uint64_t	carps_badvhid;		/* bad VHID */
110	uint64_t	carps_badaddrs;		/* bad address list */
111
112	uint64_t	carps_opackets;		/* total output packets, IPv4 */
113	uint64_t	carps_opackets6;	/* total output packets, IPv6 */
114	uint64_t	carps_onomem;		/* no memory for an mbuf */
115	uint64_t	carps_ostates;		/* total state updates sent */
116
117	uint64_t	carps_preempt;		/* if enabled, preemptions */
118};
119
120#ifdef _KERNEL
121#define	CARPSTATS_ADD(name, val)	carpstats.name += (val)
122#define	CARPSTATS_INC(name)		CARPSTATS_ADD(name, 1)
123#endif
124
125/*
126 * Configuration structure for SIOCSVH SIOCGVH
127 */
128struct carpreq {
129	int		carpr_state;
130#define	CARP_STATES	"INIT", "BACKUP", "MASTER"
131#define	CARP_MAXSTATE	2
132	int		carpr_vhid;
133	int		carpr_advskew;
134	int		carpr_advbase;
135	unsigned char	carpr_key[CARP_KEY_LEN];
136};
137#define	SIOCSVH	_IOWR('i', 245, struct ifreq)
138#define	SIOCGVH	_IOWR('i', 246, struct ifreq)
139
140/*
141 * Names for CARP sysctl objects
142 */
143#define	CARPCTL_ALLOW		1	/* accept incoming CARP packets */
144#define	CARPCTL_PREEMPT		2	/* high-pri backup preemption mode */
145#define	CARPCTL_LOG		3	/* log bad packets */
146#define	CARPCTL_STATS		4	/* statistics (read-only) */
147#define	CARPCTL_ARPBALANCE	5	/* balance arp responses */
148#define	CARPCTL_MAXID		6
149
150#define	CARPCTL_NAMES { \
151	{ 0, 0 }, \
152	{ "allow", CTLTYPE_INT }, \
153	{ "preempt", CTLTYPE_INT }, \
154	{ "log", CTLTYPE_INT }, \
155	{ "stats", CTLTYPE_STRUCT }, \
156	{ "arpbalance", CTLTYPE_INT }, \
157}
158
159#ifdef _KERNEL
160void		 carp_carpdev_state(struct ifnet *);
161void		 carp_input (struct mbuf *, int);
162int		 carp6_input (struct mbuf **, int *, int);
163int		 carp_output (struct ifnet *, struct mbuf *, struct sockaddr *,
164		     struct rtentry *);
165int		 carp_iamatch (struct ifnet *, struct in_ifaddr *, struct in_addr *,
166		     u_int8_t **);
167struct ifaddr	*carp_iamatch6(struct ifnet *, struct in6_addr *);
168caddr_t		carp_macmatch6(struct ifnet *, struct mbuf *, const struct in6_addr *);
169struct	ifnet	*carp_forus (struct ifnet *, u_char *);
170#endif
171#endif /* _IP_CARP_H */
172