xref: /freebsd/sys/netinet/ip_carp.h (revision adf376485712c8fffbf3be330d505a969647f479)
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 
62 struct 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
82 CTASSERT(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  */
101 struct 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  */
125 struct 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
141 int		carp_ioctl(struct ifreq *, u_long, struct thread *);
142 int		carp_attach(struct ifaddr *, int);
143 void		carp_detach(struct ifaddr *, bool);
144 void		carp_carpdev_state(struct ifnet *);
145 int		carp_output (struct ifnet *, struct mbuf *,
146 		    const struct sockaddr *);
147 int		carp_master(struct ifaddr *);
148 int		carp_iamatch(struct ifaddr *, uint8_t **);
149 struct ifaddr	*carp_iamatch6(struct ifnet *, struct in6_addr *);
150 char *		carp_macmatch6(struct ifnet *, struct mbuf *, const struct in6_addr *);
151 int		carp_forus(struct ifnet *, u_char *);
152 
153 /* These are external networking stack hooks for CARP */
154 /* net/if.c */
155 extern int (*carp_ioctl_p)(struct ifreq *, u_long, struct thread *);
156 extern int (*carp_attach_p)(struct ifaddr *, int);
157 extern void (*carp_detach_p)(struct ifaddr *, bool);
158 extern void (*carp_linkstate_p)(struct ifnet *);
159 extern void (*carp_demote_adj_p)(int, char *);
160 extern int (*carp_master_p)(struct ifaddr *);
161 /* net/if_bridge.c net/if_ethersubr.c */
162 extern int (*carp_forus_p)(struct ifnet *, u_char *);
163 /* net/if_ethersubr.c */
164 extern int (*carp_output_p)(struct ifnet *, struct mbuf *,
165     const struct sockaddr *);
166 /* net/rtsock.c */
167 extern int (*carp_get_vhid_p)(struct ifaddr *);
168 #ifdef INET
169 /* netinet/if_ether.c */
170 extern int (*carp_iamatch_p)(struct ifaddr *, uint8_t **);
171 #endif
172 #ifdef INET6
173 /* netinet6/nd6_nbr.c */
174 extern struct ifaddr *(*carp_iamatch6_p)(struct ifnet *, struct in6_addr *);
175 extern char * (*carp_macmatch6_p)(struct ifnet *, struct mbuf *,
176     const struct in6_addr *);
177 #endif
178 #endif
179 #endif /* _IP_CARP_H */
180