1 /*	$OpenBSD: ip_carp.h,v 1.7 2004/05/05 01:20:12 mcbride Exp $	*/
2 
3 /*
4  * Copyright (c) 2002 Michael Shalayeff. All rights reserved.
5  * Copyright (c) 2003 Ryan McBride. All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR OR HIS RELATIVES BE LIABLE FOR ANY DIRECT,
20  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22  * SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
24  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
25  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
26  * THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 struct carp_header {
30 #if BYTE_ORDER == LITTLE_ENDIAN
31 	u_int8_t	carp_type:4,
32 			carp_version:4;
33 #endif
34 #if BYTE_ORDER == BIG_ENDIAN
35 	u_int8_t	carp_version:4,
36 			carp_type:4;
37 #endif
38 	u_int8_t	carp_vhid;	/* virtual host id */
39 	u_int8_t	carp_advskew;	/* advertisement skew */
40 	u_int8_t	carp_authlen;   /* size of counter+md, 32bit chunks */
41 	u_int8_t	carp_pad1;	/* reserved */
42 	u_int8_t	carp_advbase;	/* advertisement interval */
43 	u_int16_t	carp_cksum;
44 	u_int32_t	carp_counter[2];
45 	unsigned char	carp_md[20];	/* sha1 message digest */
46 } __packed;
47 
48 #define	CARP_DFLTTL		255
49 
50 /* carp_version */
51 #define	CARP_VERSION		2
52 
53 /* carp_type */
54 #define	CARP_ADVERTISEMENT	0x01
55 
56 #define	CARP_KEY_LEN		20	/* a sha1 hash of a passphrase */
57 
58 /* carp_advbase */
59 #define	CARP_DFLTINTV		1
60 
61 /*
62  * Statistics.
63  */
64 struct carpstats {
65 	u_int64_t	carps_ipackets;		/* total input packets, IPv4 */
66 	u_int64_t	carps_ipackets6;	/* total input packets, IPv6 */
67 	u_int64_t	carps_badif;		/* wrong interface */
68 	u_int64_t	carps_badttl;		/* TTL is not CARP_DFLTTL */
69 	u_int64_t	carps_hdrops;		/* packets shorter than hdr */
70 	u_int64_t	carps_badsum;		/* bad checksum */
71 	u_int64_t	carps_badver;		/* bad (incl unsupp) version */
72 	u_int64_t	carps_badlen;		/* data length does not match */
73 	u_int64_t	carps_badauth;		/* bad authentication */
74 	u_int64_t	carps_badvhid;		/* bad VHID */
75 	u_int64_t	carps_badaddrs;		/* bad address list */
76 
77 	u_int64_t	carps_opackets;		/* total output packets, IPv4 */
78 	u_int64_t	carps_opackets6;	/* total output packets, IPv6 */
79 	u_int64_t	carps_onomem;		/* no memory for an mbuf */
80 	u_int64_t	carps_ostates;		/* total state updates sent */
81 
82 	u_int64_t	carps_preempt;		/* if enabled, preemptions */
83 };
84 
85 /*
86  * Configuration structure for SIOCSVH SIOCGVH
87  */
88 struct carpreq {
89 	int		carpr_state;
90 #define	CARP_STATES	"INIT", "BACKUP", "MASTER"
91 #define	CARP_MAXSTATE	2
92 	int		carpr_vhid;
93 	int		carpr_advskew;
94 	int		carpr_advbase;
95 	unsigned char	carpr_key[CARP_KEY_LEN];
96 };
97 #define	SIOCSVH	_IOWR('i', 245, struct ifreq)
98 #define	SIOCGVH	_IOWR('i', 246, struct ifreq)
99 
100 /*
101  * Names for CARP sysctl objects
102  */
103 #define	CARPCTL_ALLOW		1	/* accept incoming CARP packets */
104 #define	CARPCTL_PREEMPT		2	/* high-pri backup preemption mode */
105 #define	CARPCTL_LOG		3	/* log bad packets */
106 #define	CARPCTL_ARPBALANCE	4	/* balance arp responses */
107 #define	CARPCTL_MAXID		5
108 
109 #define	CARPCTL_NAMES { \
110 	{ 0, 0 }, \
111 	{ "allow", CTLTYPE_INT }, \
112 	{ "preempt", CTLTYPE_INT }, \
113 	{ "log", CTLTYPE_INT }, \
114 	{ "arpbalance", CTLTYPE_INT }, \
115 }
116 
117 #ifdef _KERNEL
118 void		 carp_ifdetach (struct ifnet *);
119 void		 carp_input (struct mbuf *, ...);
120 void		 carp_carpdev_state(void *);
121 int		 carp6_input (struct mbuf **, int *, int);
122 int		 carp_output (struct ifnet *, struct mbuf *, struct sockaddr *,
123 		     struct rtentry *);
124 int		 carp_iamatch (void *, struct in_ifaddr *, struct in_addr *,
125 		     u_int8_t **);
126 struct ifaddr	*carp_iamatch6(void *, struct in6_addr *);
127 void		*carp_macmatch6(void *, struct mbuf *, struct in6_addr *);
128 struct	ifnet	*carp_forus (void *, void *);
129 int		 carp_sysctl (int *, u_int,  void *, size_t *, void *, size_t);
130 #endif
131