ip_carp.h

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/*      $FreeBSD$       */
/*      $OpenBSD: ip_carp.h,v 1.8 2004/07/29 22:12:15 mcbride Exp $     */
 
/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2002 Michael Shalayeff. All rights reserved.
 * Copyright (c) 2003 Ryan McBride. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR OR HIS RELATIVES BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */
 
#ifndef _IP_CARP_H
#define _IP_CARP_H
 
/*
 * The CARP header layout is as follows:
 *
 *     0                   1                   2                   3
 *     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
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *    |Version| Type  | VirtualHostID |    AdvSkew    |    Auth Len   |
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *    |   Reserved    |     AdvBase   |          Checksum             |
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *    |                         Counter (1)                           |
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *    |                         Counter (2)                           |
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *    |                        SHA-1 HMAC (1)                         |
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *    |                        SHA-1 HMAC (2)                         |
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *    |                        SHA-1 HMAC (3)                         |
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *    |                        SHA-1 HMAC (4)                         |
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *    |                        SHA-1 HMAC (5)                         |
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 */
 
struct carp_header {
#if BYTE_ORDER == LITTLE_ENDIAN
        u_int8_t        carp_type:4,
                        carp_version:4;
#endif
#if BYTE_ORDER == BIG_ENDIAN
        u_int8_t        carp_version:4,
                        carp_type:4;
#endif
        u_int8_t        carp_vhid;      /* virtual host id */
        u_int8_t        carp_advskew;   /* advertisement skew */
        u_int8_t        carp_authlen;   /* size of counter+md, 32bit chunks */
        u_int8_t        carp_pad1;      /* reserved */
        u_int8_t        carp_advbase;   /* advertisement interval */
        u_int16_t       carp_cksum;
        u_int32_t       carp_counter[2];
        unsigned char   carp_md[20];    /* SHA1 HMAC */
} __packed;
 
#ifdef CTASSERT
CTASSERT(sizeof(struct carp_header) == 36);
#endif
 
#define CARP_DFLTTL             255
 
/* carp_version */
#define CARP_VERSION            2
 
/* carp_type */
#define CARP_ADVERTISEMENT      0x01
 
#define CARP_KEY_LEN            20      /* a sha1 hash of a passphrase */
 
/* carp_advbase */
#define CARP_DFLTINTV           1
 
/*
 * Statistics.
 */
struct carpstats {
        uint64_t        carps_ipackets;         /* total input packets, IPv4 */
        uint64_t        carps_ipackets6;        /* total input packets, IPv6 */
        uint64_t        carps_badif;            /* wrong interface */
        uint64_t        carps_badttl;           /* TTL is not CARP_DFLTTL */
        uint64_t        carps_hdrops;           /* packets shorter than hdr */
        uint64_t        carps_badsum;           /* bad checksum */
        uint64_t        carps_badver;           /* bad (incl unsupp) version */
        uint64_t        carps_badlen;           /* data length does not match */
        uint64_t        carps_badauth;          /* bad authentication */
        uint64_t        carps_badvhid;          /* bad VHID */
        uint64_t        carps_badaddrs;         /* bad address list */
 
        uint64_t        carps_opackets;         /* total output packets, IPv4 */
        uint64_t        carps_opackets6;        /* total output packets, IPv6 */
        uint64_t        carps_onomem;           /* no memory for an mbuf */
        uint64_t        carps_ostates;          /* total state updates sent */
 
        uint64_t        carps_preempt;          /* if enabled, preemptions */
};
 
/*
 * Configuration structure for SIOCSVH SIOCGVH
 */
struct carpreq {
        int             carpr_count;
        int             carpr_vhid;
#define CARP_MAXVHID    255
        int             carpr_state;
#define CARP_STATES     "INIT", "BACKUP", "MASTER"
#define CARP_MAXSTATE   2
        int             carpr_advskew;
#define CARP_MAXSKEW    240
        int             carpr_advbase;
        unsigned char   carpr_key[CARP_KEY_LEN];
};
#define SIOCSVH _IOWR('i', 245, struct ifreq)
#define SIOCGVH _IOWR('i', 246, struct ifreq)
 
#ifdef _KERNEL
int             carp_ioctl(struct ifreq *, u_long, struct thread *);
int             carp_attach(struct ifaddr *, int);
void            carp_detach(struct ifaddr *, bool);
void            carp_carpdev_state(struct ifnet *);
int             carp_input(struct mbuf **, int *, int);
int             carp6_input (struct mbuf **, int *, int);
int             carp_output (struct ifnet *, struct mbuf *,
                    const struct sockaddr *);
int             carp_master(struct ifaddr *);
int             carp_iamatch(struct ifaddr *, uint8_t **);
struct ifaddr   *carp_iamatch6(struct ifnet *, struct in6_addr *);
char *          carp_macmatch6(struct ifnet *, struct mbuf *, const struct in6_addr *);
int             carp_forus(struct ifnet *, u_char *);
 
/* These are external networking stack hooks for CARP */
/* net/if.c */
extern int (*carp_ioctl_p)(struct ifreq *, u_long, struct thread *);
extern int (*carp_attach_p)(struct ifaddr *, int);
extern void (*carp_detach_p)(struct ifaddr *, bool);
extern void (*carp_linkstate_p)(struct ifnet *);
extern void (*carp_demote_adj_p)(int, char *);
extern int (*carp_master_p)(struct ifaddr *);
/* net/if_bridge.c net/if_ethersubr.c */
extern int (*carp_forus_p)(struct ifnet *, u_char *);
/* net/if_ethersubr.c */
extern int (*carp_output_p)(struct ifnet *, struct mbuf *,
    const struct sockaddr *);
/* net/rtsock.c */
extern int (*carp_get_vhid_p)(struct ifaddr *);
#ifdef INET
/* netinet/if_ether.c */
extern int (*carp_iamatch_p)(struct ifaddr *, uint8_t **);
#endif
#ifdef INET6
/* netinet6/nd6_nbr.c */
extern struct ifaddr *(*carp_iamatch6_p)(struct ifnet *, struct in6_addr *);
extern char * (*carp_macmatch6_p)(struct ifnet *, struct mbuf *,
    const struct in6_addr *);
#endif
#endif
#endif /* _IP_CARP_H */