1 /* $OpenBSD: ip_carp.h,v 1.8 2004/07/29 22:12:15 mcbride Exp $ */ 2 3 /*- 4 * SPDX-License-Identifier: BSD-2-Clause 5 * 6 * Copyright (c) 2002 Michael Shalayeff. All rights reserved. 7 * Copyright (c) 2003 Ryan McBride. All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR OR HIS RELATIVES BE LIABLE FOR ANY DIRECT, 22 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 23 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 24 * SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 26 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 27 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 28 * THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #ifndef _IP_CARP_H 32 #define _IP_CARP_H 33 34 #ifdef _KERNEL 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 CTASSERT(sizeof(struct carp_header) == 36); 82 83 /* 84 * The VRRPv3 header layout is as follows: 85 * See RFC9568, 5.1. VRRP Packet Format 86 * 87 * 0 1 2 3 88 * 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 89 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 90 * |Version| Type | Virtual Rtr ID| Priority |Count IPvX Addr| 91 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 92 * |(rsvd) | Max Adver Int | Checksum | 93 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 94 * | | 95 * + + 96 * | IPvX Address(es) | 97 * + + 98 * + + 99 * + + 100 * + + 101 * | | 102 * + + 103 * | | 104 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 105 * 106 */ 107 108 struct vrrpv3_header { 109 #if BYTE_ORDER == LITTLE_ENDIAN 110 uint8_t vrrp_type:4, 111 vrrp_version:4; 112 #endif 113 #if BYTE_ORDER == BIG_ENDIAN 114 uint8_t vrrp_version:4, 115 vrrp_type:4; 116 #endif 117 uint8_t vrrp_vrtid; 118 uint8_t vrrp_priority; 119 uint8_t vrrp_count_addr; 120 uint16_t vrrp_max_adver_int; 121 uint16_t vrrp_checksum; 122 } __packed; 123 124 CTASSERT(sizeof(struct vrrpv3_header) == 8); 125 #endif /* _KERNEL */ 126 127 #define CARP_DFLTTL 255 128 129 /* carp_type */ 130 #define CARP_ADVERTISEMENT 0x01 131 132 #define CARP_KEY_LEN 20 /* a sha1 hash of a passphrase */ 133 134 /* carp_advbase */ 135 #define CARP_DFLTINTV 1 136 137 #define VRRP_TYPE_ADVERTISEMENT 0x01 138 #define VRRP_MAX_INTERVAL (0x1000 - 1) 139 /* 140 * Statistics. 141 */ 142 struct carpstats { 143 uint64_t carps_ipackets; /* total input packets, IPv4 */ 144 uint64_t carps_ipackets6; /* total input packets, IPv6 */ 145 uint64_t carps_badif; /* wrong interface */ 146 uint64_t carps_badttl; /* TTL is not CARP_DFLTTL */ 147 uint64_t carps_hdrops; /* packets shorter than hdr */ 148 uint64_t carps_badsum; /* bad checksum */ 149 uint64_t carps_badver; /* bad (incl unsupp) version */ 150 uint64_t carps_badlen; /* data length does not match */ 151 uint64_t carps_badauth; /* bad authentication */ 152 uint64_t carps_badvhid; /* bad VHID */ 153 uint64_t carps_badaddrs; /* bad address list */ 154 155 uint64_t carps_opackets; /* total output packets, IPv4 */ 156 uint64_t carps_opackets6; /* total output packets, IPv6 */ 157 uint64_t carps_onomem; /* no memory for an mbuf */ 158 uint64_t carps_ostates; /* total state updates sent */ 159 160 uint64_t carps_preempt; /* if enabled, preemptions */ 161 }; 162 163 #define CARP_MAXVHID 255 164 #define CARP_STATES "INIT", "BACKUP", "MASTER" 165 #define CARP_MAXSTATE 2 166 #define CARP_MAXSKEW 240 167 168 typedef enum carp_version { 169 CARP_VERSION_CARP = 2, 170 CARP_VERSION_VRRPv3 = 3, 171 } carp_version_t; 172 173 #ifdef _KERNEL 174 int carp_attach(struct ifaddr *, int); 175 void carp_detach(struct ifaddr *, bool); 176 void carp_carpdev_state(struct ifnet *); 177 int carp_output (struct ifnet *, struct mbuf *, 178 const struct sockaddr *); 179 int carp_master(struct ifaddr *); 180 int carp_iamatch(struct ifaddr *, uint8_t **); 181 struct ifaddr *carp_iamatch6(struct ifnet *, struct in6_addr *); 182 char * carp_macmatch6(struct ifnet *, struct mbuf *, const struct in6_addr *); 183 int carp_forus(struct ifnet *, u_char *); 184 185 /* These are external networking stack hooks for CARP */ 186 /* net/if.c */ 187 extern int (*carp_attach_p)(struct ifaddr *, int); 188 extern void (*carp_detach_p)(struct ifaddr *, bool); 189 extern void (*carp_linkstate_p)(struct ifnet *); 190 extern void (*carp_demote_adj_p)(int, char *); 191 extern int (*carp_master_p)(struct ifaddr *); 192 /* net/if_bridge.c net/if_ethersubr.c */ 193 extern int (*carp_forus_p)(struct ifnet *, u_char *); 194 /* net/if_ethersubr.c */ 195 extern int (*carp_output_p)(struct ifnet *, struct mbuf *, 196 const struct sockaddr *); 197 /* net/rtsock.c */ 198 extern int (*carp_get_vhid_p)(struct ifaddr *); 199 #ifdef INET 200 /* netinet/if_ether.c */ 201 extern int (*carp_iamatch_p)(struct ifaddr *, uint8_t **); 202 #endif 203 #ifdef INET6 204 /* netinet6/nd6_nbr.c */ 205 extern struct ifaddr *(*carp_iamatch6_p)(struct ifnet *, struct in6_addr *); 206 extern char * (*carp_macmatch6_p)(struct ifnet *, struct mbuf *, 207 const struct in6_addr *); 208 #endif 209 #endif 210 #endif /* _IP_CARP_H */ 211