1/*	$FreeBSD$	*/
2/*	$OpenBSD: ip_carp.h,v 1.8 2004/07/29 22:12:15 mcbride Exp $	*/
3
4/*-
5 * SPDX-License-Identifier: BSD-2-Clause
6 *
7 * Copyright (c) 2002 Michael Shalayeff. All rights reserved.
8 * Copyright (c) 2003 Ryan McBride. All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR OR HIS RELATIVES BE LIABLE FOR ANY DIRECT,
23 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
24 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
25 * SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
27 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
28 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
29 * THE POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#ifndef _IP_CARP_H
33#define	_IP_CARP_H
34
35/*
36 * The CARP header layout is as follows:
37 *
38 *     0                   1                   2                   3
39 *     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
40 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
41 *    |Version| Type  | VirtualHostID |    AdvSkew    |    Auth Len   |
42 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
43 *    |   Reserved    |     AdvBase   |          Checksum             |
44 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
45 *    |                         Counter (1)                           |
46 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
47 *    |                         Counter (2)                           |
48 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
49 *    |                        SHA-1 HMAC (1)                         |
50 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
51 *    |                        SHA-1 HMAC (2)                         |
52 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
53 *    |                        SHA-1 HMAC (3)                         |
54 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
55 *    |                        SHA-1 HMAC (4)                         |
56 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
57 *    |                        SHA-1 HMAC (5)                         |
58 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
59 *
60 */
61
62struct carp_header {
63#if BYTE_ORDER == LITTLE_ENDIAN
64	u_int8_t	carp_type:4,
65			carp_version:4;
66#endif
67#if BYTE_ORDER == BIG_ENDIAN
68	u_int8_t	carp_version:4,
69			carp_type:4;
70#endif
71	u_int8_t	carp_vhid;	/* virtual host id */
72	u_int8_t	carp_advskew;	/* advertisement skew */
73	u_int8_t	carp_authlen;   /* size of counter+md, 32bit chunks */
74	u_int8_t	carp_pad1;	/* reserved */
75	u_int8_t	carp_advbase;	/* advertisement interval */
76	u_int16_t	carp_cksum;
77	u_int32_t	carp_counter[2];
78	unsigned char	carp_md[20];	/* SHA1 HMAC */
79} __packed;
80
81#ifdef CTASSERT
82CTASSERT(sizeof(struct carp_header) == 36);
83#endif
84
85#define	CARP_DFLTTL		255
86
87/* carp_version */
88#define	CARP_VERSION		2
89
90/* carp_type */
91#define	CARP_ADVERTISEMENT	0x01
92
93#define	CARP_KEY_LEN		20	/* a sha1 hash of a passphrase */
94
95/* carp_advbase */
96#define	CARP_DFLTINTV		1
97
98/*
99 * Statistics.
100 */
101struct carpstats {
102	uint64_t	carps_ipackets;		/* total input packets, IPv4 */
103	uint64_t	carps_ipackets6;	/* total input packets, IPv6 */
104	uint64_t	carps_badif;		/* wrong interface */
105	uint64_t	carps_badttl;		/* TTL is not CARP_DFLTTL */
106	uint64_t	carps_hdrops;		/* packets shorter than hdr */
107	uint64_t	carps_badsum;		/* bad checksum */
108	uint64_t	carps_badver;		/* bad (incl unsupp) version */
109	uint64_t	carps_badlen;		/* data length does not match */
110	uint64_t	carps_badauth;		/* bad authentication */
111	uint64_t	carps_badvhid;		/* bad VHID */
112	uint64_t	carps_badaddrs;		/* bad address list */
113
114	uint64_t	carps_opackets;		/* total output packets, IPv4 */
115	uint64_t	carps_opackets6;	/* total output packets, IPv6 */
116	uint64_t	carps_onomem;		/* no memory for an mbuf */
117	uint64_t	carps_ostates;		/* total state updates sent */
118
119	uint64_t	carps_preempt;		/* if enabled, preemptions */
120};
121
122/*
123 * Configuration structure for SIOCSVH SIOCGVH
124 */
125struct carpreq {
126	int		carpr_count;
127	int		carpr_vhid;
128#define	CARP_MAXVHID	255
129	int		carpr_state;
130#define	CARP_STATES	"INIT", "BACKUP", "MASTER"
131#define	CARP_MAXSTATE	2
132	int		carpr_advskew;
133#define	CARP_MAXSKEW	240
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#ifdef _KERNEL
141int		carp_ioctl(struct ifreq *, u_long, struct thread *);
142int		carp_attach(struct ifaddr *, int);
143void		carp_detach(struct ifaddr *, bool);
144void		carp_carpdev_state(struct ifnet *);
145int		carp_input(struct mbuf **, int *, int);
146int		carp6_input (struct mbuf **, int *, int);
147int		carp_output (struct ifnet *, struct mbuf *,
148		    const struct sockaddr *);
149int		carp_master(struct ifaddr *);
150int		carp_iamatch(struct ifaddr *, uint8_t **);
151struct ifaddr	*carp_iamatch6(struct ifnet *, struct in6_addr *);
152char *		carp_macmatch6(struct ifnet *, struct mbuf *, const struct in6_addr *);
153int		carp_forus(struct ifnet *, u_char *);
154
155/* These are external networking stack hooks for CARP */
156/* net/if.c */
157extern int (*carp_ioctl_p)(struct ifreq *, u_long, struct thread *);
158extern int (*carp_attach_p)(struct ifaddr *, int);
159extern void (*carp_detach_p)(struct ifaddr *, bool);
160extern void (*carp_linkstate_p)(struct ifnet *);
161extern void (*carp_demote_adj_p)(int, char *);
162extern int (*carp_master_p)(struct ifaddr *);
163/* net/if_bridge.c net/if_ethersubr.c */
164extern int (*carp_forus_p)(struct ifnet *, u_char *);
165/* net/if_ethersubr.c */
166extern int (*carp_output_p)(struct ifnet *, struct mbuf *,
167    const struct sockaddr *);
168/* net/rtsock.c */
169extern int (*carp_get_vhid_p)(struct ifaddr *);
170#ifdef INET
171/* netinet/if_ether.c */
172extern int (*carp_iamatch_p)(struct ifaddr *, uint8_t **);
173#endif
174#ifdef INET6
175/* netinet6/nd6_nbr.c */
176extern struct ifaddr *(*carp_iamatch6_p)(struct ifnet *, struct in6_addr *);
177extern char * (*carp_macmatch6_p)(struct ifnet *, struct mbuf *,
178    const struct in6_addr *);
179#endif
180#endif
181#endif /* _IP_CARP_H */
182