freebsd-dev/sys/netinet/ip_carp.c
Robert Watson acd3428b7d Sweep kernel replacing suser(9) calls with priv(9) calls, assigning
specific privilege names to a broad range of privileges.  These may
require some future tweaking.

Sponsored by:           nCircle Network Security, Inc.
Obtained from:          TrustedBSD Project
Discussed on:           arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
                        Alex Lyashkov <umka at sevcity dot net>,
                        Skip Ford <skip dot ford at verizon dot net>,
                        Antoine Brodin <antoine dot brodin at laposte dot net>
2006-11-06 13:42:10 +00:00

2197 lines
52 KiB
C

/* $FreeBSD$ */
/*
* 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.
*/
#include "opt_carp.h"
#include "opt_bpf.h"
#include "opt_inet.h"
#include "opt_inet6.h"
#include <sys/types.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/kernel.h>
#include <sys/limits.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/module.h>
#include <sys/time.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/sysctl.h>
#include <sys/syslog.h>
#include <sys/signalvar.h>
#include <sys/filio.h>
#include <sys/sockio.h>
#include <sys/socket.h>
#include <sys/vnode.h>
#include <machine/stdarg.h>
#include <net/bpf.h>
#include <net/ethernet.h>
#include <net/fddi.h>
#include <net/iso88025.h>
#include <net/if.h>
#include <net/if_clone.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/route.h>
#ifdef INET
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/if_ether.h>
#include <machine/in_cksum.h>
#endif
#ifdef INET6
#include <netinet/icmp6.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/scope6_var.h>
#include <netinet6/nd6.h>
#endif
#include <crypto/sha1.h>
#include <netinet/ip_carp.h>
#define CARP_IFNAME "carp"
static MALLOC_DEFINE(M_CARP, "CARP", "CARP interfaces");
SYSCTL_DECL(_net_inet_carp);
struct carp_softc {
struct ifnet *sc_ifp; /* Interface clue */
struct ifnet *sc_carpdev; /* Pointer to parent interface */
struct in_ifaddr *sc_ia; /* primary iface address */
struct ip_moptions sc_imo;
#ifdef INET6
struct in6_ifaddr *sc_ia6; /* primary iface address v6 */
struct ip6_moptions sc_im6o;
#endif /* INET6 */
TAILQ_ENTRY(carp_softc) sc_list;
enum { INIT = 0, BACKUP, MASTER } sc_state;
int sc_flags_backup;
int sc_suppress;
int sc_sendad_errors;
#define CARP_SENDAD_MAX_ERRORS 3
int sc_sendad_success;
#define CARP_SENDAD_MIN_SUCCESS 3
int sc_vhid;
int sc_advskew;
int sc_naddrs;
int sc_naddrs6;
int sc_advbase; /* seconds */
int sc_init_counter;
u_int64_t sc_counter;
/* authentication */
#define CARP_HMAC_PAD 64
unsigned char sc_key[CARP_KEY_LEN];
unsigned char sc_pad[CARP_HMAC_PAD];
SHA1_CTX sc_sha1;
struct callout sc_ad_tmo; /* advertisement timeout */
struct callout sc_md_tmo; /* master down timeout */
struct callout sc_md6_tmo; /* master down timeout */
LIST_ENTRY(carp_softc) sc_next; /* Interface clue */
};
#define SC2IFP(sc) ((sc)->sc_ifp)
int carp_suppress_preempt = 0;
int carp_opts[CARPCTL_MAXID] = { 0, 1, 0, 1, 0, 0 }; /* XXX for now */
SYSCTL_INT(_net_inet_carp, CARPCTL_ALLOW, allow, CTLFLAG_RW,
&carp_opts[CARPCTL_ALLOW], 0, "Accept incoming CARP packets");
SYSCTL_INT(_net_inet_carp, CARPCTL_PREEMPT, preempt, CTLFLAG_RW,
&carp_opts[CARPCTL_PREEMPT], 0, "high-priority backup preemption mode");
SYSCTL_INT(_net_inet_carp, CARPCTL_LOG, log, CTLFLAG_RW,
&carp_opts[CARPCTL_LOG], 0, "log bad carp packets");
SYSCTL_INT(_net_inet_carp, CARPCTL_ARPBALANCE, arpbalance, CTLFLAG_RW,
&carp_opts[CARPCTL_ARPBALANCE], 0, "balance arp responses");
SYSCTL_INT(_net_inet_carp, OID_AUTO, suppress_preempt, CTLFLAG_RD,
&carp_suppress_preempt, 0, "Preemption is suppressed");
struct carpstats carpstats;
SYSCTL_STRUCT(_net_inet_carp, CARPCTL_STATS, stats, CTLFLAG_RW,
&carpstats, carpstats,
"CARP statistics (struct carpstats, netinet/ip_carp.h)");
struct carp_if {
TAILQ_HEAD(, carp_softc) vhif_vrs;
int vhif_nvrs;
struct ifnet *vhif_ifp;
struct mtx vhif_mtx;
};
/* Get carp_if from softc. Valid after carp_set_addr{,6}. */
#define SC2CIF(sc) ((struct carp_if *)(sc)->sc_carpdev->if_carp)
/* lock per carp_if queue */
#define CARP_LOCK_INIT(cif) mtx_init(&(cif)->vhif_mtx, "carp_if", \
NULL, MTX_DEF)
#define CARP_LOCK_DESTROY(cif) mtx_destroy(&(cif)->vhif_mtx)
#define CARP_LOCK_ASSERT(cif) mtx_assert(&(cif)->vhif_mtx, MA_OWNED)
#define CARP_LOCK(cif) mtx_lock(&(cif)->vhif_mtx)
#define CARP_UNLOCK(cif) mtx_unlock(&(cif)->vhif_mtx)
#define CARP_SCLOCK(sc) mtx_lock(&SC2CIF(sc)->vhif_mtx)
#define CARP_SCUNLOCK(sc) mtx_unlock(&SC2CIF(sc)->vhif_mtx)
#define CARP_SCLOCK_ASSERT(sc) mtx_assert(&SC2CIF(sc)->vhif_mtx, MA_OWNED)
#define CARP_LOG(...) do { \
if (carp_opts[CARPCTL_LOG] > 0) \
log(LOG_INFO, __VA_ARGS__); \
} while (0)
#define CARP_DEBUG(...) do { \
if (carp_opts[CARPCTL_LOG] > 1) \
log(LOG_DEBUG, __VA_ARGS__); \
} while (0)
static void carp_hmac_prepare(struct carp_softc *);
static void carp_hmac_generate(struct carp_softc *, u_int32_t *,
unsigned char *);
static int carp_hmac_verify(struct carp_softc *, u_int32_t *,
unsigned char *);
static void carp_setroute(struct carp_softc *, int);
static void carp_input_c(struct mbuf *, struct carp_header *, sa_family_t);
static int carp_clone_create(struct if_clone *, int, caddr_t);
static void carp_clone_destroy(struct ifnet *);
static void carpdetach(struct carp_softc *);
static int carp_prepare_ad(struct mbuf *, struct carp_softc *,
struct carp_header *);
static void carp_send_ad_all(void);
static void carp_send_ad(void *);
static void carp_send_ad_locked(struct carp_softc *);
static void carp_send_arp(struct carp_softc *);
static void carp_master_down(void *);
static void carp_master_down_locked(struct carp_softc *);
static int carp_ioctl(struct ifnet *, u_long, caddr_t);
static int carp_looutput(struct ifnet *, struct mbuf *, struct sockaddr *,
struct rtentry *);
static void carp_start(struct ifnet *);
static void carp_setrun(struct carp_softc *, sa_family_t);
static void carp_set_state(struct carp_softc *, int);
static int carp_addrcount(struct carp_if *, struct in_ifaddr *, int);
enum { CARP_COUNT_MASTER, CARP_COUNT_RUNNING };
static void carp_multicast_cleanup(struct carp_softc *);
static int carp_set_addr(struct carp_softc *, struct sockaddr_in *);
static int carp_del_addr(struct carp_softc *, struct sockaddr_in *);
static void carp_carpdev_state_locked(struct carp_if *);
static void carp_sc_state_locked(struct carp_softc *);
#ifdef INET6
static void carp_send_na(struct carp_softc *);
static int carp_set_addr6(struct carp_softc *, struct sockaddr_in6 *);
static int carp_del_addr6(struct carp_softc *, struct sockaddr_in6 *);
#endif
static LIST_HEAD(, carp_softc) carpif_list;
static struct mtx carp_mtx;
IFC_SIMPLE_DECLARE(carp, 0);
static eventhandler_tag if_detach_event_tag;
static __inline u_int16_t
carp_cksum(struct mbuf *m, int len)
{
return (in_cksum(m, len));
}
static void
carp_hmac_prepare(struct carp_softc *sc)
{
u_int8_t version = CARP_VERSION, type = CARP_ADVERTISEMENT;
u_int8_t vhid = sc->sc_vhid & 0xff;
struct ifaddr *ifa;
int i;
#ifdef INET6
struct in6_addr in6;
#endif
if (sc->sc_carpdev)
CARP_SCLOCK(sc);
/* XXX: possible race here */
/* compute ipad from key */
bzero(sc->sc_pad, sizeof(sc->sc_pad));
bcopy(sc->sc_key, sc->sc_pad, sizeof(sc->sc_key));
for (i = 0; i < sizeof(sc->sc_pad); i++)
sc->sc_pad[i] ^= 0x36;
/* precompute first part of inner hash */
SHA1Init(&sc->sc_sha1);
SHA1Update(&sc->sc_sha1, sc->sc_pad, sizeof(sc->sc_pad));
SHA1Update(&sc->sc_sha1, (void *)&version, sizeof(version));
SHA1Update(&sc->sc_sha1, (void *)&type, sizeof(type));
SHA1Update(&sc->sc_sha1, (void *)&vhid, sizeof(vhid));
#ifdef INET
TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) {
if (ifa->ifa_addr->sa_family == AF_INET)
SHA1Update(&sc->sc_sha1,
(void *)&ifatoia(ifa)->ia_addr.sin_addr.s_addr,
sizeof(struct in_addr));
}
#endif /* INET */
#ifdef INET6
TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) {
if (ifa->ifa_addr->sa_family == AF_INET6) {
in6 = ifatoia6(ifa)->ia_addr.sin6_addr;
in6_clearscope(&in6);
SHA1Update(&sc->sc_sha1, (void *)&in6, sizeof(in6));
}
}
#endif /* INET6 */
/* convert ipad to opad */
for (i = 0; i < sizeof(sc->sc_pad); i++)
sc->sc_pad[i] ^= 0x36 ^ 0x5c;
if (sc->sc_carpdev)
CARP_SCUNLOCK(sc);
}
static void
carp_hmac_generate(struct carp_softc *sc, u_int32_t counter[2],
unsigned char md[20])
{
SHA1_CTX sha1ctx;
/* fetch first half of inner hash */
bcopy(&sc->sc_sha1, &sha1ctx, sizeof(sha1ctx));
SHA1Update(&sha1ctx, (void *)counter, sizeof(sc->sc_counter));
SHA1Final(md, &sha1ctx);
/* outer hash */
SHA1Init(&sha1ctx);
SHA1Update(&sha1ctx, sc->sc_pad, sizeof(sc->sc_pad));
SHA1Update(&sha1ctx, md, 20);
SHA1Final(md, &sha1ctx);
}
static int
carp_hmac_verify(struct carp_softc *sc, u_int32_t counter[2],
unsigned char md[20])
{
unsigned char md2[20];
CARP_SCLOCK_ASSERT(sc);
carp_hmac_generate(sc, counter, md2);
return (bcmp(md, md2, sizeof(md2)));
}
static void
carp_setroute(struct carp_softc *sc, int cmd)
{
struct ifaddr *ifa;
int s;
if (sc->sc_carpdev)
CARP_SCLOCK_ASSERT(sc);
s = splnet();
TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) {
if (ifa->ifa_addr->sa_family == AF_INET &&
sc->sc_carpdev != NULL) {
int count = carp_addrcount(
(struct carp_if *)sc->sc_carpdev->if_carp,
ifatoia(ifa), CARP_COUNT_MASTER);
if ((cmd == RTM_ADD && count == 1) ||
(cmd == RTM_DELETE && count == 0))
rtinit(ifa, cmd, RTF_UP | RTF_HOST);
}
#ifdef INET6
if (ifa->ifa_addr->sa_family == AF_INET6) {
if (cmd == RTM_ADD)
in6_ifaddloop(ifa);
else
in6_ifremloop(ifa);
}
#endif /* INET6 */
}
splx(s);
}
static int
carp_clone_create(struct if_clone *ifc, int unit, caddr_t params)
{
struct carp_softc *sc;
struct ifnet *ifp;
MALLOC(sc, struct carp_softc *, sizeof(*sc), M_CARP, M_WAITOK|M_ZERO);
ifp = SC2IFP(sc) = if_alloc(IFT_ETHER);
if (ifp == NULL) {
FREE(sc, M_CARP);
return (ENOSPC);
}
sc->sc_flags_backup = 0;
sc->sc_suppress = 0;
sc->sc_advbase = CARP_DFLTINTV;
sc->sc_vhid = -1; /* required setting */
sc->sc_advskew = 0;
sc->sc_init_counter = 1;
sc->sc_naddrs = sc->sc_naddrs6 = 0; /* M_ZERO? */
#ifdef INET6
sc->sc_im6o.im6o_multicast_hlim = CARP_DFLTTL;
#endif
sc->sc_imo.imo_membership = (struct in_multi **)malloc(
(sizeof(struct in_multi *) * IP_MIN_MEMBERSHIPS), M_CARP,
M_WAITOK);
sc->sc_imo.imo_max_memberships = IP_MIN_MEMBERSHIPS;
sc->sc_imo.imo_multicast_vif = -1;
callout_init(&sc->sc_ad_tmo, NET_CALLOUT_MPSAFE);
callout_init(&sc->sc_md_tmo, NET_CALLOUT_MPSAFE);
callout_init(&sc->sc_md6_tmo, NET_CALLOUT_MPSAFE);
ifp->if_softc = sc;
if_initname(ifp, CARP_IFNAME, unit);
ifp->if_mtu = ETHERMTU;
ifp->if_flags = IFF_LOOPBACK;
ifp->if_ioctl = carp_ioctl;
ifp->if_output = carp_looutput;
ifp->if_start = carp_start;
ifp->if_type = IFT_CARP;
ifp->if_snd.ifq_maxlen = ifqmaxlen;
ifp->if_hdrlen = 0;
if_attach(ifp);
bpfattach(SC2IFP(sc), DLT_NULL, sizeof(u_int32_t));
mtx_lock(&carp_mtx);
LIST_INSERT_HEAD(&carpif_list, sc, sc_next);
mtx_unlock(&carp_mtx);
return (0);
}
static void
carp_clone_destroy(struct ifnet *ifp)
{
struct carp_softc *sc = ifp->if_softc;
if (sc->sc_carpdev)
CARP_SCLOCK(sc);
carpdetach(sc);
if (sc->sc_carpdev)
CARP_SCUNLOCK(sc);
mtx_lock(&carp_mtx);
LIST_REMOVE(sc, sc_next);
mtx_unlock(&carp_mtx);
bpfdetach(ifp);
if_detach(ifp);
if_free_type(ifp, IFT_ETHER);
free(sc->sc_imo.imo_membership, M_CARP);
free(sc, M_CARP);
}
static void
carpdetach(struct carp_softc *sc)
{
struct carp_if *cif;
callout_stop(&sc->sc_ad_tmo);
callout_stop(&sc->sc_md_tmo);
callout_stop(&sc->sc_md6_tmo);
if (sc->sc_suppress)
carp_suppress_preempt--;
sc->sc_suppress = 0;
if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS)
carp_suppress_preempt--;
sc->sc_sendad_errors = 0;
carp_set_state(sc, INIT);
SC2IFP(sc)->if_flags &= ~IFF_UP;
carp_setrun(sc, 0);
carp_multicast_cleanup(sc);
if (sc->sc_carpdev != NULL) {
cif = (struct carp_if *)sc->sc_carpdev->if_carp;
CARP_LOCK_ASSERT(cif);
TAILQ_REMOVE(&cif->vhif_vrs, sc, sc_list);
if (!--cif->vhif_nvrs) {
ifpromisc(sc->sc_carpdev, 0);
sc->sc_carpdev->if_carp = NULL;
CARP_LOCK_DESTROY(cif);
FREE(cif, M_IFADDR);
}
}
sc->sc_carpdev = NULL;
}
/* Detach an interface from the carp. */
static void
carp_ifdetach(void *arg __unused, struct ifnet *ifp)
{
struct carp_if *cif = (struct carp_if *)ifp->if_carp;
struct carp_softc *sc, *nextsc;
if (cif == NULL)
return;
/*
* XXX: At the end of for() cycle the lock will be destroyed.
*/
CARP_LOCK(cif);
for (sc = TAILQ_FIRST(&cif->vhif_vrs); sc; sc = nextsc) {
nextsc = TAILQ_NEXT(sc, sc_list);
carpdetach(sc);
}
}
/*
* process input packet.
* we have rearranged checks order compared to the rfc,
* but it seems more efficient this way or not possible otherwise.
*/
void
carp_input(struct mbuf *m, int hlen)
{
struct ip *ip = mtod(m, struct ip *);
struct carp_header *ch;
int iplen, len;
carpstats.carps_ipackets++;
if (!carp_opts[CARPCTL_ALLOW]) {
m_freem(m);
return;
}
/* check if received on a valid carp interface */
if (m->m_pkthdr.rcvif->if_carp == NULL) {
carpstats.carps_badif++;
CARP_LOG("carp_input: packet received on non-carp "
"interface: %s\n",
m->m_pkthdr.rcvif->if_xname);
m_freem(m);
return;
}
/* verify that the IP TTL is 255. */
if (ip->ip_ttl != CARP_DFLTTL) {
carpstats.carps_badttl++;
CARP_LOG("carp_input: received ttl %d != 255i on %s\n",
ip->ip_ttl,
m->m_pkthdr.rcvif->if_xname);
m_freem(m);
return;
}
iplen = ip->ip_hl << 2;
if (m->m_pkthdr.len < iplen + sizeof(*ch)) {
carpstats.carps_badlen++;
CARP_LOG("carp_input: received len %zd < "
"sizeof(struct carp_header)\n",
m->m_len - sizeof(struct ip));
m_freem(m);
return;
}
if (iplen + sizeof(*ch) < m->m_len) {
if ((m = m_pullup(m, iplen + sizeof(*ch))) == NULL) {
carpstats.carps_hdrops++;
CARP_LOG("carp_input: pullup failed\n");
return;
}
ip = mtod(m, struct ip *);
}
ch = (struct carp_header *)((char *)ip + iplen);
/*
* verify that the received packet length is
* equal to the CARP header
*/
len = iplen + sizeof(*ch);
if (len > m->m_pkthdr.len) {
carpstats.carps_badlen++;
CARP_LOG("carp_input: packet too short %d on %s\n",
m->m_pkthdr.len,
m->m_pkthdr.rcvif->if_xname);
m_freem(m);
return;
}
if ((m = m_pullup(m, len)) == NULL) {
carpstats.carps_hdrops++;
return;
}
ip = mtod(m, struct ip *);
ch = (struct carp_header *)((char *)ip + iplen);
/* verify the CARP checksum */
m->m_data += iplen;
if (carp_cksum(m, len - iplen)) {
carpstats.carps_badsum++;
CARP_LOG("carp_input: checksum failed on %s\n",
m->m_pkthdr.rcvif->if_xname);
m_freem(m);
return;
}
m->m_data -= iplen;
carp_input_c(m, ch, AF_INET);
}
#ifdef INET6
int
carp6_input(struct mbuf **mp, int *offp, int proto)
{
struct mbuf *m = *mp;
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
struct carp_header *ch;
u_int len;
carpstats.carps_ipackets6++;
if (!carp_opts[CARPCTL_ALLOW]) {
m_freem(m);
return (IPPROTO_DONE);
}
/* check if received on a valid carp interface */
if (m->m_pkthdr.rcvif->if_carp == NULL) {
carpstats.carps_badif++;
CARP_LOG("carp6_input: packet received on non-carp "
"interface: %s\n",
m->m_pkthdr.rcvif->if_xname);
m_freem(m);
return (IPPROTO_DONE);
}
/* verify that the IP TTL is 255 */
if (ip6->ip6_hlim != CARP_DFLTTL) {
carpstats.carps_badttl++;
CARP_LOG("carp6_input: received ttl %d != 255 on %s\n",
ip6->ip6_hlim,
m->m_pkthdr.rcvif->if_xname);
m_freem(m);
return (IPPROTO_DONE);
}
/* verify that we have a complete carp packet */
len = m->m_len;
IP6_EXTHDR_GET(ch, struct carp_header *, m, *offp, sizeof(*ch));
if (ch == NULL) {
carpstats.carps_badlen++;
CARP_LOG("carp6_input: packet size %u too small\n", len);
return (IPPROTO_DONE);
}
/* verify the CARP checksum */
m->m_data += *offp;
if (carp_cksum(m, sizeof(*ch))) {
carpstats.carps_badsum++;
CARP_LOG("carp6_input: checksum failed, on %s\n",
m->m_pkthdr.rcvif->if_xname);
m_freem(m);
return (IPPROTO_DONE);
}
m->m_data -= *offp;
carp_input_c(m, ch, AF_INET6);
return (IPPROTO_DONE);
}
#endif /* INET6 */
static void
carp_input_c(struct mbuf *m, struct carp_header *ch, sa_family_t af)
{
struct ifnet *ifp = m->m_pkthdr.rcvif;
struct carp_softc *sc;
u_int64_t tmp_counter;
struct timeval sc_tv, ch_tv;
/* verify that the VHID is valid on the receiving interface */
CARP_LOCK(ifp->if_carp);
TAILQ_FOREACH(sc, &((struct carp_if *)ifp->if_carp)->vhif_vrs, sc_list)
if (sc->sc_vhid == ch->carp_vhid)
break;
if (!sc || !((SC2IFP(sc)->if_flags & IFF_UP) &&
(SC2IFP(sc)->if_drv_flags & IFF_DRV_RUNNING))) {
carpstats.carps_badvhid++;
CARP_UNLOCK(ifp->if_carp);
m_freem(m);
return;
}
getmicrotime(&SC2IFP(sc)->if_lastchange);
SC2IFP(sc)->if_ipackets++;
SC2IFP(sc)->if_ibytes += m->m_pkthdr.len;
if (bpf_peers_present(SC2IFP(sc)->if_bpf)) {
struct ip *ip = mtod(m, struct ip *);
uint32_t af1 = af;
/* BPF wants net byte order */
ip->ip_len = htons(ip->ip_len + (ip->ip_hl << 2));
ip->ip_off = htons(ip->ip_off);
bpf_mtap2(SC2IFP(sc)->if_bpf, &af1, sizeof(af1), m);
}
/* verify the CARP version. */
if (ch->carp_version != CARP_VERSION) {
carpstats.carps_badver++;
SC2IFP(sc)->if_ierrors++;
CARP_UNLOCK(ifp->if_carp);
CARP_LOG("%s; invalid version %d\n",
SC2IFP(sc)->if_xname,
ch->carp_version);
m_freem(m);
return;
}
/* verify the hash */
if (carp_hmac_verify(sc, ch->carp_counter, ch->carp_md)) {
carpstats.carps_badauth++;
SC2IFP(sc)->if_ierrors++;
CARP_UNLOCK(ifp->if_carp);
CARP_LOG("%s: incorrect hash\n", SC2IFP(sc)->if_xname);
m_freem(m);
return;
}
tmp_counter = ntohl(ch->carp_counter[0]);
tmp_counter = tmp_counter<<32;
tmp_counter += ntohl(ch->carp_counter[1]);
/* XXX Replay protection goes here */
sc->sc_init_counter = 0;
sc->sc_counter = tmp_counter;
sc_tv.tv_sec = sc->sc_advbase;
if (carp_suppress_preempt && sc->sc_advskew < 240)
sc_tv.tv_usec = 240 * 1000000 / 256;
else
sc_tv.tv_usec = sc->sc_advskew * 1000000 / 256;
ch_tv.tv_sec = ch->carp_advbase;
ch_tv.tv_usec = ch->carp_advskew * 1000000 / 256;
switch (sc->sc_state) {
case INIT:
break;
case MASTER:
/*
* If we receive an advertisement from a master who's going to
* be more frequent than us, go into BACKUP state.
*/
if (timevalcmp(&sc_tv, &ch_tv, >) ||
timevalcmp(&sc_tv, &ch_tv, ==)) {
callout_stop(&sc->sc_ad_tmo);
CARP_DEBUG("%s: MASTER -> BACKUP "
"(more frequent advertisement received)\n",
SC2IFP(sc)->if_xname);
carp_set_state(sc, BACKUP);
carp_setrun(sc, 0);
carp_setroute(sc, RTM_DELETE);
}
break;
case BACKUP:
/*
* If we're pre-empting masters who advertise slower than us,
* and this one claims to be slower, treat him as down.
*/
if (carp_opts[CARPCTL_PREEMPT] &&
timevalcmp(&sc_tv, &ch_tv, <)) {
CARP_DEBUG("%s: BACKUP -> MASTER "
"(preempting a slower master)\n",
SC2IFP(sc)->if_xname);
carp_master_down_locked(sc);
break;
}
/*
* If the master is going to advertise at such a low frequency
* that he's guaranteed to time out, we'd might as well just
* treat him as timed out now.
*/
sc_tv.tv_sec = sc->sc_advbase * 3;
if (timevalcmp(&sc_tv, &ch_tv, <)) {
CARP_DEBUG("%s: BACKUP -> MASTER "
"(master timed out)\n",
SC2IFP(sc)->if_xname);
carp_master_down_locked(sc);
break;
}
/*
* Otherwise, we reset the counter and wait for the next
* advertisement.
*/
carp_setrun(sc, af);
break;
}
CARP_UNLOCK(ifp->if_carp);
m_freem(m);
return;
}
static int
carp_prepare_ad(struct mbuf *m, struct carp_softc *sc, struct carp_header *ch)
{
struct m_tag *mtag;
struct ifnet *ifp = SC2IFP(sc);
if (sc->sc_init_counter) {
/* this could also be seconds since unix epoch */
sc->sc_counter = arc4random();
sc->sc_counter = sc->sc_counter << 32;
sc->sc_counter += arc4random();
} else
sc->sc_counter++;
ch->carp_counter[0] = htonl((sc->sc_counter>>32)&0xffffffff);
ch->carp_counter[1] = htonl(sc->sc_counter&0xffffffff);
carp_hmac_generate(sc, ch->carp_counter, ch->carp_md);
/* Tag packet for carp_output */
mtag = m_tag_get(PACKET_TAG_CARP, sizeof(struct ifnet *), M_NOWAIT);
if (mtag == NULL) {
m_freem(m);
SC2IFP(sc)->if_oerrors++;
return (ENOMEM);
}
bcopy(&ifp, (caddr_t)(mtag + 1), sizeof(struct ifnet *));
m_tag_prepend(m, mtag);
return (0);
}
static void
carp_send_ad_all(void)
{
struct carp_softc *sc;
mtx_lock(&carp_mtx);
LIST_FOREACH(sc, &carpif_list, sc_next) {
if (sc->sc_carpdev == NULL)
continue;
CARP_SCLOCK(sc);
if ((SC2IFP(sc)->if_flags & IFF_UP) &&
(SC2IFP(sc)->if_drv_flags & IFF_DRV_RUNNING) &&
sc->sc_state == MASTER)
carp_send_ad_locked(sc);
CARP_SCUNLOCK(sc);
}
mtx_unlock(&carp_mtx);
}
static void
carp_send_ad(void *v)
{
struct carp_softc *sc = v;
CARP_SCLOCK(sc);
carp_send_ad_locked(sc);
CARP_SCUNLOCK(sc);
}
static void
carp_send_ad_locked(struct carp_softc *sc)
{
struct carp_header ch;
struct timeval tv;
struct carp_header *ch_ptr;
struct mbuf *m;
int len, advbase, advskew;
CARP_SCLOCK_ASSERT(sc);
/* bow out if we've lost our UPness or RUNNINGuiness */
if (!((SC2IFP(sc)->if_flags & IFF_UP) &&
(SC2IFP(sc)->if_drv_flags & IFF_DRV_RUNNING))) {
advbase = 255;
advskew = 255;
} else {
advbase = sc->sc_advbase;
if (!carp_suppress_preempt || sc->sc_advskew > 240)
advskew = sc->sc_advskew;
else
advskew = 240;
tv.tv_sec = advbase;
tv.tv_usec = advskew * 1000000 / 256;
}
ch.carp_version = CARP_VERSION;
ch.carp_type = CARP_ADVERTISEMENT;
ch.carp_vhid = sc->sc_vhid;
ch.carp_advbase = advbase;
ch.carp_advskew = advskew;
ch.carp_authlen = 7; /* XXX DEFINE */
ch.carp_pad1 = 0; /* must be zero */
ch.carp_cksum = 0;
#ifdef INET
if (sc->sc_ia) {
struct ip *ip;
MGETHDR(m, M_DONTWAIT, MT_HEADER);
if (m == NULL) {
SC2IFP(sc)->if_oerrors++;
carpstats.carps_onomem++;
/* XXX maybe less ? */
if (advbase != 255 || advskew != 255)
callout_reset(&sc->sc_ad_tmo, tvtohz(&tv),
carp_send_ad, sc);
return;
}
len = sizeof(*ip) + sizeof(ch);
m->m_pkthdr.len = len;
m->m_pkthdr.rcvif = NULL;
m->m_len = len;
MH_ALIGN(m, m->m_len);
m->m_flags |= M_MCAST;
ip = mtod(m, struct ip *);
ip->ip_v = IPVERSION;
ip->ip_hl = sizeof(*ip) >> 2;
ip->ip_tos = IPTOS_LOWDELAY;
ip->ip_len = len;
ip->ip_id = ip_newid();
ip->ip_off = IP_DF;
ip->ip_ttl = CARP_DFLTTL;
ip->ip_p = IPPROTO_CARP;
ip->ip_sum = 0;
ip->ip_src.s_addr = sc->sc_ia->ia_addr.sin_addr.s_addr;
ip->ip_dst.s_addr = htonl(INADDR_CARP_GROUP);
ch_ptr = (struct carp_header *)(&ip[1]);
bcopy(&ch, ch_ptr, sizeof(ch));
if (carp_prepare_ad(m, sc, ch_ptr))
return;
m->m_data += sizeof(*ip);
ch_ptr->carp_cksum = carp_cksum(m, len - sizeof(*ip));
m->m_data -= sizeof(*ip);
getmicrotime(&SC2IFP(sc)->if_lastchange);
SC2IFP(sc)->if_opackets++;
SC2IFP(sc)->if_obytes += len;
carpstats.carps_opackets++;
if (ip_output(m, NULL, NULL, IP_RAWOUTPUT, &sc->sc_imo, NULL)) {
SC2IFP(sc)->if_oerrors++;
if (sc->sc_sendad_errors < INT_MAX)
sc->sc_sendad_errors++;
if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) {
carp_suppress_preempt++;
if (carp_suppress_preempt == 1) {
CARP_SCUNLOCK(sc);
carp_send_ad_all();
CARP_SCLOCK(sc);
}
}
sc->sc_sendad_success = 0;
} else {
if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS) {
if (++sc->sc_sendad_success >=
CARP_SENDAD_MIN_SUCCESS) {
carp_suppress_preempt--;
sc->sc_sendad_errors = 0;
}
} else
sc->sc_sendad_errors = 0;
}
}
#endif /* INET */
#ifdef INET6
if (sc->sc_ia6) {
struct ip6_hdr *ip6;
MGETHDR(m, M_DONTWAIT, MT_HEADER);
if (m == NULL) {
SC2IFP(sc)->if_oerrors++;
carpstats.carps_onomem++;
/* XXX maybe less ? */
if (advbase != 255 || advskew != 255)
callout_reset(&sc->sc_ad_tmo, tvtohz(&tv),
carp_send_ad, sc);
return;
}
len = sizeof(*ip6) + sizeof(ch);
m->m_pkthdr.len = len;
m->m_pkthdr.rcvif = NULL;
m->m_len = len;
MH_ALIGN(m, m->m_len);
m->m_flags |= M_MCAST;
ip6 = mtod(m, struct ip6_hdr *);
bzero(ip6, sizeof(*ip6));
ip6->ip6_vfc |= IPV6_VERSION;
ip6->ip6_hlim = CARP_DFLTTL;
ip6->ip6_nxt = IPPROTO_CARP;
bcopy(&sc->sc_ia6->ia_addr.sin6_addr, &ip6->ip6_src,
sizeof(struct in6_addr));
/* set the multicast destination */
ip6->ip6_dst.s6_addr16[0] = htons(0xff02);
ip6->ip6_dst.s6_addr8[15] = 0x12;
if (in6_setscope(&ip6->ip6_dst, sc->sc_carpdev, NULL) != 0) {
SC2IFP(sc)->if_oerrors++;
m_freem(m);
CARP_LOG("%s: in6_setscope failed\n", __func__);
return;
}
ch_ptr = (struct carp_header *)(&ip6[1]);
bcopy(&ch, ch_ptr, sizeof(ch));
if (carp_prepare_ad(m, sc, ch_ptr))
return;
m->m_data += sizeof(*ip6);
ch_ptr->carp_cksum = carp_cksum(m, len - sizeof(*ip6));
m->m_data -= sizeof(*ip6);
getmicrotime(&SC2IFP(sc)->if_lastchange);
SC2IFP(sc)->if_opackets++;
SC2IFP(sc)->if_obytes += len;
carpstats.carps_opackets6++;
if (ip6_output(m, NULL, NULL, 0, &sc->sc_im6o, NULL, NULL)) {
SC2IFP(sc)->if_oerrors++;
if (sc->sc_sendad_errors < INT_MAX)
sc->sc_sendad_errors++;
if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) {
carp_suppress_preempt++;
if (carp_suppress_preempt == 1) {
CARP_SCUNLOCK(sc);
carp_send_ad_all();
CARP_SCLOCK(sc);
}
}
sc->sc_sendad_success = 0;
} else {
if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS) {
if (++sc->sc_sendad_success >=
CARP_SENDAD_MIN_SUCCESS) {
carp_suppress_preempt--;
sc->sc_sendad_errors = 0;
}
} else
sc->sc_sendad_errors = 0;
}
}
#endif /* INET6 */
if (advbase != 255 || advskew != 255)
callout_reset(&sc->sc_ad_tmo, tvtohz(&tv),
carp_send_ad, sc);
}
/*
* Broadcast a gratuitous ARP request containing
* the virtual router MAC address for each IP address
* associated with the virtual router.
*/
static void
carp_send_arp(struct carp_softc *sc)
{
struct ifaddr *ifa;
TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) {
if (ifa->ifa_addr->sa_family != AF_INET)
continue;
/* arprequest(sc->sc_carpdev, &in, &in, IF_LLADDR(sc->sc_ifp)); */
arp_ifinit2(sc->sc_carpdev, ifa, IF_LLADDR(sc->sc_ifp));
DELAY(1000); /* XXX */
}
}
#ifdef INET6
static void
carp_send_na(struct carp_softc *sc)
{
struct ifaddr *ifa;
struct in6_addr *in6;
static struct in6_addr mcast = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) {
if (ifa->ifa_addr->sa_family != AF_INET6)
continue;
in6 = &ifatoia6(ifa)->ia_addr.sin6_addr;
nd6_na_output(sc->sc_carpdev, &mcast, in6,
ND_NA_FLAG_OVERRIDE, 1, NULL);
DELAY(1000); /* XXX */
}
}
#endif /* INET6 */
static int
carp_addrcount(struct carp_if *cif, struct in_ifaddr *ia, int type)
{
struct carp_softc *vh;
struct ifaddr *ifa;
int count = 0;
CARP_LOCK_ASSERT(cif);
TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) {
if ((type == CARP_COUNT_RUNNING &&
(SC2IFP(vh)->if_flags & IFF_UP) &&
(SC2IFP(vh)->if_drv_flags & IFF_DRV_RUNNING)) ||
(type == CARP_COUNT_MASTER && vh->sc_state == MASTER)) {
TAILQ_FOREACH(ifa, &SC2IFP(vh)->if_addrlist,
ifa_list) {
if (ifa->ifa_addr->sa_family == AF_INET &&
ia->ia_addr.sin_addr.s_addr ==
ifatoia(ifa)->ia_addr.sin_addr.s_addr)
count++;
}
}
}
return (count);
}
int
carp_iamatch(void *v, struct in_ifaddr *ia,
struct in_addr *isaddr, u_int8_t **enaddr)
{
struct carp_if *cif = v;
struct carp_softc *vh;
int index, count = 0;
struct ifaddr *ifa;
CARP_LOCK(cif);
if (carp_opts[CARPCTL_ARPBALANCE]) {
/*
* XXX proof of concept implementation.
* We use the source ip to decide which virtual host should
* handle the request. If we're master of that virtual host,
* then we respond, otherwise, just drop the arp packet on
* the floor.
*/
count = carp_addrcount(cif, ia, CARP_COUNT_RUNNING);
if (count == 0) {
/* should never reach this */
CARP_UNLOCK(cif);
return (0);
}
/* this should be a hash, like pf_hash() */
index = ntohl(isaddr->s_addr) % count;
count = 0;
TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) {
if ((SC2IFP(vh)->if_flags & IFF_UP) &&
(SC2IFP(vh)->if_drv_flags & IFF_DRV_RUNNING)) {
TAILQ_FOREACH(ifa, &SC2IFP(vh)->if_addrlist,
ifa_list) {
if (ifa->ifa_addr->sa_family ==
AF_INET &&
ia->ia_addr.sin_addr.s_addr ==
ifatoia(ifa)->ia_addr.sin_addr.s_addr) {
if (count == index) {
if (vh->sc_state ==
MASTER) {
*enaddr = IF_LLADDR(vh->sc_ifp);
CARP_UNLOCK(cif);
return (1);
} else {
CARP_UNLOCK(cif);
return (0);
}
}
count++;
}
}
}
}
} else {
TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) {
if ((SC2IFP(vh)->if_flags & IFF_UP) &&
(SC2IFP(vh)->if_drv_flags & IFF_DRV_RUNNING) &&
ia->ia_ifp == SC2IFP(vh) &&
vh->sc_state == MASTER) {
*enaddr = IF_LLADDR(vh->sc_ifp);
CARP_UNLOCK(cif);
return (1);
}
}
}
CARP_UNLOCK(cif);
return (0);
}
#ifdef INET6
struct ifaddr *
carp_iamatch6(void *v, struct in6_addr *taddr)
{
struct carp_if *cif = v;
struct carp_softc *vh;
struct ifaddr *ifa;
CARP_LOCK(cif);
TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) {
TAILQ_FOREACH(ifa, &SC2IFP(vh)->if_addrlist, ifa_list) {
if (IN6_ARE_ADDR_EQUAL(taddr,
&ifatoia6(ifa)->ia_addr.sin6_addr) &&
(SC2IFP(vh)->if_flags & IFF_UP) &&
(SC2IFP(vh)->if_drv_flags & IFF_DRV_RUNNING) &&
vh->sc_state == MASTER) {
CARP_UNLOCK(cif);
return (ifa);
}
}
}
CARP_UNLOCK(cif);
return (NULL);
}
void *
carp_macmatch6(void *v, struct mbuf *m, const struct in6_addr *taddr)
{
struct m_tag *mtag;
struct carp_if *cif = v;
struct carp_softc *sc;
struct ifaddr *ifa;
CARP_LOCK(cif);
TAILQ_FOREACH(sc, &cif->vhif_vrs, sc_list) {
TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) {
if (IN6_ARE_ADDR_EQUAL(taddr,
&ifatoia6(ifa)->ia_addr.sin6_addr) &&
(SC2IFP(sc)->if_flags & IFF_UP) &&
(SC2IFP(sc)->if_drv_flags & IFF_DRV_RUNNING)) {
struct ifnet *ifp = SC2IFP(sc);
mtag = m_tag_get(PACKET_TAG_CARP,
sizeof(struct ifnet *), M_NOWAIT);
if (mtag == NULL) {
/* better a bit than nothing */
CARP_UNLOCK(cif);
return (IF_LLADDR(sc->sc_ifp));
}
bcopy(&ifp, (caddr_t)(mtag + 1),
sizeof(struct ifnet *));
m_tag_prepend(m, mtag);
CARP_UNLOCK(cif);
return (IF_LLADDR(sc->sc_ifp));
}
}
}
CARP_UNLOCK(cif);
return (NULL);
}
#endif
struct ifnet *
carp_forus(void *v, void *dhost)
{
struct carp_if *cif = v;
struct carp_softc *vh;
u_int8_t *ena = dhost;
if (ena[0] || ena[1] || ena[2] != 0x5e || ena[3] || ena[4] != 1)
return (NULL);
CARP_LOCK(cif);
TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list)
if ((SC2IFP(vh)->if_flags & IFF_UP) &&
(SC2IFP(vh)->if_drv_flags & IFF_DRV_RUNNING) &&
vh->sc_state == MASTER &&
!bcmp(dhost, IF_LLADDR(vh->sc_ifp), ETHER_ADDR_LEN)) {
CARP_UNLOCK(cif);
return (SC2IFP(vh));
}
CARP_UNLOCK(cif);
return (NULL);
}
static void
carp_master_down(void *v)
{
struct carp_softc *sc = v;
CARP_SCLOCK(sc);
carp_master_down_locked(sc);
CARP_SCUNLOCK(sc);
}
static void
carp_master_down_locked(struct carp_softc *sc)
{
if (sc->sc_carpdev)
CARP_SCLOCK_ASSERT(sc);
switch (sc->sc_state) {
case INIT:
printf("%s: master_down event in INIT state\n",
SC2IFP(sc)->if_xname);
break;
case MASTER:
break;
case BACKUP:
carp_set_state(sc, MASTER);
carp_send_ad_locked(sc);
carp_send_arp(sc);
#ifdef INET6
carp_send_na(sc);
#endif /* INET6 */
carp_setrun(sc, 0);
carp_setroute(sc, RTM_ADD);
break;
}
}
/*
* When in backup state, af indicates whether to reset the master down timer
* for v4 or v6. If it's set to zero, reset the ones which are already pending.
*/
static void
carp_setrun(struct carp_softc *sc, sa_family_t af)
{
struct timeval tv;
if (sc->sc_carpdev == NULL) {
SC2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING;
carp_set_state(sc, INIT);
return;
} else
CARP_SCLOCK_ASSERT(sc);
if (SC2IFP(sc)->if_flags & IFF_UP &&
sc->sc_vhid > 0 && (sc->sc_naddrs || sc->sc_naddrs6))
SC2IFP(sc)->if_drv_flags |= IFF_DRV_RUNNING;
else {
SC2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING;
carp_setroute(sc, RTM_DELETE);
return;
}
switch (sc->sc_state) {
case INIT:
if (carp_opts[CARPCTL_PREEMPT] && !carp_suppress_preempt) {
carp_send_ad_locked(sc);
carp_send_arp(sc);
#ifdef INET6
carp_send_na(sc);
#endif /* INET6 */
CARP_DEBUG("%s: INIT -> MASTER (preempting)\n",
SC2IFP(sc)->if_xname);
carp_set_state(sc, MASTER);
carp_setroute(sc, RTM_ADD);
} else {
CARP_DEBUG("%s: INIT -> BACKUP\n", SC2IFP(sc)->if_xname);
carp_set_state(sc, BACKUP);
carp_setroute(sc, RTM_DELETE);
carp_setrun(sc, 0);
}
break;
case BACKUP:
callout_stop(&sc->sc_ad_tmo);
tv.tv_sec = 3 * sc->sc_advbase;
tv.tv_usec = sc->sc_advskew * 1000000 / 256;
switch (af) {
#ifdef INET
case AF_INET:
callout_reset(&sc->sc_md_tmo, tvtohz(&tv),
carp_master_down, sc);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
callout_reset(&sc->sc_md6_tmo, tvtohz(&tv),
carp_master_down, sc);
break;
#endif /* INET6 */
default:
if (sc->sc_naddrs)
callout_reset(&sc->sc_md_tmo, tvtohz(&tv),
carp_master_down, sc);
if (sc->sc_naddrs6)
callout_reset(&sc->sc_md6_tmo, tvtohz(&tv),
carp_master_down, sc);
break;
}
break;
case MASTER:
tv.tv_sec = sc->sc_advbase;
tv.tv_usec = sc->sc_advskew * 1000000 / 256;
callout_reset(&sc->sc_ad_tmo, tvtohz(&tv),
carp_send_ad, sc);
break;
}
}
void
carp_multicast_cleanup(struct carp_softc *sc)
{
struct ip_moptions *imo = &sc->sc_imo;
#ifdef INET6
struct ip6_moptions *im6o = &sc->sc_im6o;
#endif
u_int16_t n = imo->imo_num_memberships;
/* Clean up our own multicast memberships */
while (n-- > 0) {
if (imo->imo_membership[n] != NULL) {
in_delmulti(imo->imo_membership[n]);
imo->imo_membership[n] = NULL;
}
}
imo->imo_num_memberships = 0;
imo->imo_multicast_ifp = NULL;
#ifdef INET6
while (!LIST_EMPTY(&im6o->im6o_memberships)) {
struct in6_multi_mship *imm =
LIST_FIRST(&im6o->im6o_memberships);
LIST_REMOVE(imm, i6mm_chain);
in6_leavegroup(imm);
}
im6o->im6o_multicast_ifp = NULL;
#endif
}
static int
carp_set_addr(struct carp_softc *sc, struct sockaddr_in *sin)
{
struct ifnet *ifp;
struct carp_if *cif;
struct in_ifaddr *ia, *ia_if;
struct ip_moptions *imo = &sc->sc_imo;
struct in_addr addr;
u_long iaddr = htonl(sin->sin_addr.s_addr);
int own, error;
if (sin->sin_addr.s_addr == 0) {
if (!(SC2IFP(sc)->if_flags & IFF_UP))
carp_set_state(sc, INIT);
if (sc->sc_naddrs)
SC2IFP(sc)->if_flags |= IFF_UP;
carp_setrun(sc, 0);
return (0);
}
/* we have to do it by hands to check we won't match on us */
ia_if = NULL; own = 0;
TAILQ_FOREACH(ia, &in_ifaddrhead, ia_link) {
/* and, yeah, we need a multicast-capable iface too */
if (ia->ia_ifp != SC2IFP(sc) &&
(ia->ia_ifp->if_flags & IFF_MULTICAST) &&
(iaddr & ia->ia_subnetmask) == ia->ia_subnet) {
if (!ia_if)
ia_if = ia;
if (sin->sin_addr.s_addr ==
ia->ia_addr.sin_addr.s_addr)
own++;
}
}
if (!ia_if)
return (EADDRNOTAVAIL);
ia = ia_if;
ifp = ia->ia_ifp;
if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0 ||
(imo->imo_multicast_ifp && imo->imo_multicast_ifp != ifp))
return (EADDRNOTAVAIL);
if (imo->imo_num_memberships == 0) {
addr.s_addr = htonl(INADDR_CARP_GROUP);
if ((imo->imo_membership[0] = in_addmulti(&addr, ifp)) == NULL)
return (ENOBUFS);
imo->imo_num_memberships++;
imo->imo_multicast_ifp = ifp;
imo->imo_multicast_ttl = CARP_DFLTTL;
imo->imo_multicast_loop = 0;
}
if (!ifp->if_carp) {
MALLOC(cif, struct carp_if *, sizeof(*cif), M_CARP,
M_WAITOK|M_ZERO);
if (!cif) {
error = ENOBUFS;
goto cleanup;
}
if ((error = ifpromisc(ifp, 1))) {
FREE(cif, M_CARP);
goto cleanup;
}
CARP_LOCK_INIT(cif);
CARP_LOCK(cif);
cif->vhif_ifp = ifp;
TAILQ_INIT(&cif->vhif_vrs);
ifp->if_carp = cif;
} else {
struct carp_softc *vr;
cif = (struct carp_if *)ifp->if_carp;
CARP_LOCK(cif);
TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list)
if (vr != sc && vr->sc_vhid == sc->sc_vhid) {
CARP_UNLOCK(cif);
error = EINVAL;
goto cleanup;
}
}
sc->sc_ia = ia;
sc->sc_carpdev = ifp;
{ /* XXX prevent endless loop if already in queue */
struct carp_softc *vr, *after = NULL;
int myself = 0;
cif = (struct carp_if *)ifp->if_carp;
/* XXX: cif should not change, right? So we still hold the lock */
CARP_LOCK_ASSERT(cif);
TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list) {
if (vr == sc)
myself = 1;
if (vr->sc_vhid < sc->sc_vhid)
after = vr;
}
if (!myself) {
/* We're trying to keep things in order */
if (after == NULL) {
TAILQ_INSERT_TAIL(&cif->vhif_vrs, sc, sc_list);
} else {
TAILQ_INSERT_AFTER(&cif->vhif_vrs, after, sc, sc_list);
}
cif->vhif_nvrs++;
}
}
sc->sc_naddrs++;
SC2IFP(sc)->if_flags |= IFF_UP;
if (own)
sc->sc_advskew = 0;
carp_sc_state_locked(sc);
carp_setrun(sc, 0);
CARP_UNLOCK(cif);
return (0);
cleanup:
in_delmulti(imo->imo_membership[--imo->imo_num_memberships]);
return (error);
}
static int
carp_del_addr(struct carp_softc *sc, struct sockaddr_in *sin)
{
int error = 0;
if (!--sc->sc_naddrs) {
struct carp_if *cif = (struct carp_if *)sc->sc_carpdev->if_carp;
struct ip_moptions *imo = &sc->sc_imo;
CARP_LOCK(cif);
callout_stop(&sc->sc_ad_tmo);
SC2IFP(sc)->if_flags &= ~IFF_UP;
SC2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING;
sc->sc_vhid = -1;
in_delmulti(imo->imo_membership[--imo->imo_num_memberships]);
imo->imo_multicast_ifp = NULL;
TAILQ_REMOVE(&cif->vhif_vrs, sc, sc_list);
if (!--cif->vhif_nvrs) {
sc->sc_carpdev->if_carp = NULL;
CARP_LOCK_DESTROY(cif);
FREE(cif, M_IFADDR);
} else {
CARP_UNLOCK(cif);
}
}
return (error);
}
#ifdef INET6
static int
carp_set_addr6(struct carp_softc *sc, struct sockaddr_in6 *sin6)
{
struct ifnet *ifp;
struct carp_if *cif;
struct in6_ifaddr *ia, *ia_if;
struct ip6_moptions *im6o = &sc->sc_im6o;
struct in6_multi_mship *imm;
struct in6_addr in6;
int own, error;
if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
if (!(SC2IFP(sc)->if_flags & IFF_UP))
carp_set_state(sc, INIT);
if (sc->sc_naddrs6)
SC2IFP(sc)->if_flags |= IFF_UP;
carp_setrun(sc, 0);
return (0);
}
/* we have to do it by hands to check we won't match on us */
ia_if = NULL; own = 0;
for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
int i;
for (i = 0; i < 4; i++) {
if ((sin6->sin6_addr.s6_addr32[i] &
ia->ia_prefixmask.sin6_addr.s6_addr32[i]) !=
(ia->ia_addr.sin6_addr.s6_addr32[i] &
ia->ia_prefixmask.sin6_addr.s6_addr32[i]))
break;
}
/* and, yeah, we need a multicast-capable iface too */
if (ia->ia_ifp != SC2IFP(sc) &&
(ia->ia_ifp->if_flags & IFF_MULTICAST) &&
(i == 4)) {
if (!ia_if)
ia_if = ia;
if (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr,
&ia->ia_addr.sin6_addr))
own++;
}
}
if (!ia_if)
return (EADDRNOTAVAIL);
ia = ia_if;
ifp = ia->ia_ifp;
if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0 ||
(im6o->im6o_multicast_ifp && im6o->im6o_multicast_ifp != ifp))
return (EADDRNOTAVAIL);
if (!sc->sc_naddrs6) {
im6o->im6o_multicast_ifp = ifp;
/* join CARP multicast address */
bzero(&in6, sizeof(in6));
in6.s6_addr16[0] = htons(0xff02);
in6.s6_addr8[15] = 0x12;
if (in6_setscope(&in6, ifp, NULL) != 0)
goto cleanup;
if ((imm = in6_joingroup(ifp, &in6, &error, 0)) == NULL)
goto cleanup;
LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain);
/* join solicited multicast address */
bzero(&in6, sizeof(in6));
in6.s6_addr16[0] = htons(0xff02);
in6.s6_addr32[1] = 0;
in6.s6_addr32[2] = htonl(1);
in6.s6_addr32[3] = sin6->sin6_addr.s6_addr32[3];
in6.s6_addr8[12] = 0xff;
if (in6_setscope(&in6, ifp, NULL) != 0)
goto cleanup;
if ((imm = in6_joingroup(ifp, &in6, &error, 0)) == NULL)
goto cleanup;
LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain);
}
if (!ifp->if_carp) {
MALLOC(cif, struct carp_if *, sizeof(*cif), M_CARP,
M_WAITOK|M_ZERO);
if (!cif) {
error = ENOBUFS;
goto cleanup;
}
if ((error = ifpromisc(ifp, 1))) {
FREE(cif, M_CARP);
goto cleanup;
}
CARP_LOCK_INIT(cif);
CARP_LOCK(cif);
cif->vhif_ifp = ifp;
TAILQ_INIT(&cif->vhif_vrs);
ifp->if_carp = cif;
} else {
struct carp_softc *vr;
cif = (struct carp_if *)ifp->if_carp;
CARP_LOCK(cif);
TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list)
if (vr != sc && vr->sc_vhid == sc->sc_vhid) {
CARP_UNLOCK(cif);
error = EINVAL;
goto cleanup;
}
}
sc->sc_ia6 = ia;
sc->sc_carpdev = ifp;
{ /* XXX prevent endless loop if already in queue */
struct carp_softc *vr, *after = NULL;
int myself = 0;
cif = (struct carp_if *)ifp->if_carp;
CARP_LOCK_ASSERT(cif);
TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list) {
if (vr == sc)
myself = 1;
if (vr->sc_vhid < sc->sc_vhid)
after = vr;
}
if (!myself) {
/* We're trying to keep things in order */
if (after == NULL) {
TAILQ_INSERT_TAIL(&cif->vhif_vrs, sc, sc_list);
} else {
TAILQ_INSERT_AFTER(&cif->vhif_vrs, after, sc, sc_list);
}
cif->vhif_nvrs++;
}
}
sc->sc_naddrs6++;
SC2IFP(sc)->if_flags |= IFF_UP;
if (own)
sc->sc_advskew = 0;
carp_sc_state_locked(sc);
carp_setrun(sc, 0);
CARP_UNLOCK(cif);
return (0);
cleanup:
/* clean up multicast memberships */
if (!sc->sc_naddrs6) {
while (!LIST_EMPTY(&im6o->im6o_memberships)) {
imm = LIST_FIRST(&im6o->im6o_memberships);
LIST_REMOVE(imm, i6mm_chain);
in6_leavegroup(imm);
}
}
return (error);
}
static int
carp_del_addr6(struct carp_softc *sc, struct sockaddr_in6 *sin6)
{
int error = 0;
if (!--sc->sc_naddrs6) {
struct carp_if *cif = (struct carp_if *)sc->sc_carpdev->if_carp;
struct ip6_moptions *im6o = &sc->sc_im6o;
CARP_LOCK(cif);
callout_stop(&sc->sc_ad_tmo);
SC2IFP(sc)->if_flags &= ~IFF_UP;
SC2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING;
sc->sc_vhid = -1;
while (!LIST_EMPTY(&im6o->im6o_memberships)) {
struct in6_multi_mship *imm =
LIST_FIRST(&im6o->im6o_memberships);
LIST_REMOVE(imm, i6mm_chain);
in6_leavegroup(imm);
}
im6o->im6o_multicast_ifp = NULL;
TAILQ_REMOVE(&cif->vhif_vrs, sc, sc_list);
if (!--cif->vhif_nvrs) {
CARP_LOCK_DESTROY(cif);
sc->sc_carpdev->if_carp = NULL;
FREE(cif, M_IFADDR);
} else
CARP_UNLOCK(cif);
}
return (error);
}
#endif /* INET6 */
static int
carp_ioctl(struct ifnet *ifp, u_long cmd, caddr_t addr)
{
struct carp_softc *sc = ifp->if_softc, *vr;
struct carpreq carpr;
struct ifaddr *ifa;
struct ifreq *ifr;
struct ifaliasreq *ifra;
int locked = 0, error = 0;
ifa = (struct ifaddr *)addr;
ifra = (struct ifaliasreq *)addr;
ifr = (struct ifreq *)addr;
switch (cmd) {
case SIOCSIFADDR:
switch (ifa->ifa_addr->sa_family) {
#ifdef INET
case AF_INET:
SC2IFP(sc)->if_flags |= IFF_UP;
bcopy(ifa->ifa_addr, ifa->ifa_dstaddr,
sizeof(struct sockaddr));
error = carp_set_addr(sc, satosin(ifa->ifa_addr));
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
SC2IFP(sc)->if_flags |= IFF_UP;
error = carp_set_addr6(sc, satosin6(ifa->ifa_addr));
break;
#endif /* INET6 */
default:
error = EAFNOSUPPORT;
break;
}
break;
case SIOCAIFADDR:
switch (ifa->ifa_addr->sa_family) {
#ifdef INET
case AF_INET:
SC2IFP(sc)->if_flags |= IFF_UP;
bcopy(ifa->ifa_addr, ifa->ifa_dstaddr,
sizeof(struct sockaddr));
error = carp_set_addr(sc, satosin(&ifra->ifra_addr));
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
SC2IFP(sc)->if_flags |= IFF_UP;
error = carp_set_addr6(sc, satosin6(&ifra->ifra_addr));
break;
#endif /* INET6 */
default:
error = EAFNOSUPPORT;
break;
}
break;
case SIOCDIFADDR:
switch (ifa->ifa_addr->sa_family) {
#ifdef INET
case AF_INET:
error = carp_del_addr(sc, satosin(&ifra->ifra_addr));
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
error = carp_del_addr6(sc, satosin6(&ifra->ifra_addr));
break;
#endif /* INET6 */
default:
error = EAFNOSUPPORT;
break;
}
break;
case SIOCSIFFLAGS:
if (sc->sc_carpdev) {
locked = 1;
CARP_SCLOCK(sc);
}
if (sc->sc_state != INIT && !(ifr->ifr_flags & IFF_UP)) {
callout_stop(&sc->sc_ad_tmo);
callout_stop(&sc->sc_md_tmo);
callout_stop(&sc->sc_md6_tmo);
if (sc->sc_state == MASTER)
carp_send_ad_locked(sc);
carp_set_state(sc, INIT);
carp_setrun(sc, 0);
} else if (sc->sc_state == INIT && (ifr->ifr_flags & IFF_UP)) {
SC2IFP(sc)->if_flags |= IFF_UP;
carp_setrun(sc, 0);
}
break;
case SIOCSVH:
error = priv_check(curthread, PRIV_NETINET_CARP);
if (error)
break;
if ((error = copyin(ifr->ifr_data, &carpr, sizeof carpr)))
break;
error = 1;
if (sc->sc_carpdev) {
locked = 1;
CARP_SCLOCK(sc);
}
if (sc->sc_state != INIT && carpr.carpr_state != sc->sc_state) {
switch (carpr.carpr_state) {
case BACKUP:
callout_stop(&sc->sc_ad_tmo);
carp_set_state(sc, BACKUP);
carp_setrun(sc, 0);
carp_setroute(sc, RTM_DELETE);
break;
case MASTER:
carp_master_down_locked(sc);
break;
default:
break;
}
}
if (carpr.carpr_vhid > 0) {
if (carpr.carpr_vhid > 255) {
error = EINVAL;
break;
}
if (sc->sc_carpdev) {
struct carp_if *cif;
cif = (struct carp_if *)sc->sc_carpdev->if_carp;
TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list)
if (vr != sc &&
vr->sc_vhid == carpr.carpr_vhid)
return EEXIST;
}
sc->sc_vhid = carpr.carpr_vhid;
IF_LLADDR(sc->sc_ifp)[0] = 0;
IF_LLADDR(sc->sc_ifp)[1] = 0;
IF_LLADDR(sc->sc_ifp)[2] = 0x5e;
IF_LLADDR(sc->sc_ifp)[3] = 0;
IF_LLADDR(sc->sc_ifp)[4] = 1;
IF_LLADDR(sc->sc_ifp)[5] = sc->sc_vhid;
error--;
}
if (carpr.carpr_advbase > 0 || carpr.carpr_advskew > 0) {
if (carpr.carpr_advskew >= 255) {
error = EINVAL;
break;
}
if (carpr.carpr_advbase > 255) {
error = EINVAL;
break;
}
sc->sc_advbase = carpr.carpr_advbase;
sc->sc_advskew = carpr.carpr_advskew;
error--;
}
bcopy(carpr.carpr_key, sc->sc_key, sizeof(sc->sc_key));
if (error > 0)
error = EINVAL;
else {
error = 0;
carp_setrun(sc, 0);
}
break;
case SIOCGVH:
/* XXX: lockless read */
bzero(&carpr, sizeof(carpr));
carpr.carpr_state = sc->sc_state;
carpr.carpr_vhid = sc->sc_vhid;
carpr.carpr_advbase = sc->sc_advbase;
carpr.carpr_advskew = sc->sc_advskew;
error = priv_check(curthread, PRIV_NETINET_CARP);
if (error == 0)
bcopy(sc->sc_key, carpr.carpr_key,
sizeof(carpr.carpr_key));
error = copyout(&carpr, ifr->ifr_data, sizeof(carpr));
break;
default:
error = EINVAL;
}
if (locked)
CARP_SCUNLOCK(sc);
carp_hmac_prepare(sc);
return (error);
}
/*
* XXX: this is looutput. We should eventually use it from there.
*/
static int
carp_looutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
struct rtentry *rt)
{
u_int32_t af;
M_ASSERTPKTHDR(m); /* check if we have the packet header */
if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
m_freem(m);
return (rt->rt_flags & RTF_BLACKHOLE ? 0 :
rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
}
ifp->if_opackets++;
ifp->if_obytes += m->m_pkthdr.len;
/* BPF writes need to be handled specially. */
if (dst->sa_family == AF_UNSPEC) {
bcopy(dst->sa_data, &af, sizeof(af));
dst->sa_family = af;
}
#if 1 /* XXX */
switch (dst->sa_family) {
case AF_INET:
case AF_INET6:
case AF_IPX:
case AF_APPLETALK:
break;
default:
printf("carp_looutput: af=%d unexpected\n", dst->sa_family);
m_freem(m);
return (EAFNOSUPPORT);
}
#endif
return(if_simloop(ifp, m, dst->sa_family, 0));
}
/*
* Start output on carp interface. This function should never be called.
*/
static void
carp_start(struct ifnet *ifp)
{
#ifdef DEBUG
printf("%s: start called\n", ifp->if_xname);
#endif
}
int
carp_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *sa,
struct rtentry *rt)
{
struct m_tag *mtag;
struct carp_softc *sc;
struct ifnet *carp_ifp;
if (!sa)
return (0);
switch (sa->sa_family) {
#ifdef INET
case AF_INET:
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
break;
#endif /* INET6 */
default:
return (0);
}
mtag = m_tag_find(m, PACKET_TAG_CARP, NULL);
if (mtag == NULL)
return (0);
bcopy(mtag + 1, &carp_ifp, sizeof(struct ifnet *));
sc = carp_ifp->if_softc;
/* Set the source MAC address to Virtual Router MAC Address */
switch (ifp->if_type) {
case IFT_ETHER:
case IFT_L2VLAN: {
struct ether_header *eh;
eh = mtod(m, struct ether_header *);
eh->ether_shost[0] = 0;
eh->ether_shost[1] = 0;
eh->ether_shost[2] = 0x5e;
eh->ether_shost[3] = 0;
eh->ether_shost[4] = 1;
eh->ether_shost[5] = sc->sc_vhid;
}
break;
case IFT_FDDI: {
struct fddi_header *fh;
fh = mtod(m, struct fddi_header *);
fh->fddi_shost[0] = 0;
fh->fddi_shost[1] = 0;
fh->fddi_shost[2] = 0x5e;
fh->fddi_shost[3] = 0;
fh->fddi_shost[4] = 1;
fh->fddi_shost[5] = sc->sc_vhid;
}
break;
case IFT_ISO88025: {
struct iso88025_header *th;
th = mtod(m, struct iso88025_header *);
th->iso88025_shost[0] = 3;
th->iso88025_shost[1] = 0;
th->iso88025_shost[2] = 0x40 >> (sc->sc_vhid - 1);
th->iso88025_shost[3] = 0x40000 >> (sc->sc_vhid - 1);
th->iso88025_shost[4] = 0;
th->iso88025_shost[5] = 0;
}
break;
default:
printf("%s: carp is not supported for this interface type\n",
ifp->if_xname);
return (EOPNOTSUPP);
}
return (0);
}
static void
carp_set_state(struct carp_softc *sc, int state)
{
if (sc->sc_carpdev)
CARP_SCLOCK_ASSERT(sc);
if (sc->sc_state == state)
return;
sc->sc_state = state;
switch (state) {
case BACKUP:
SC2IFP(sc)->if_link_state = LINK_STATE_DOWN;
break;
case MASTER:
SC2IFP(sc)->if_link_state = LINK_STATE_UP;
break;
default:
SC2IFP(sc)->if_link_state = LINK_STATE_UNKNOWN;
break;
}
rt_ifmsg(SC2IFP(sc));
}
void
carp_carpdev_state(void *v)
{
struct carp_if *cif = v;
CARP_LOCK(cif);
carp_carpdev_state_locked(cif);
CARP_UNLOCK(cif);
}
static void
carp_carpdev_state_locked(struct carp_if *cif)
{
struct carp_softc *sc;
TAILQ_FOREACH(sc, &cif->vhif_vrs, sc_list)
carp_sc_state_locked(sc);
}
static void
carp_sc_state_locked(struct carp_softc *sc)
{
CARP_SCLOCK_ASSERT(sc);
if (sc->sc_carpdev->if_link_state != LINK_STATE_UP ||
!(sc->sc_carpdev->if_flags & IFF_UP)) {
sc->sc_flags_backup = SC2IFP(sc)->if_flags;
SC2IFP(sc)->if_flags &= ~IFF_UP;
SC2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING;
callout_stop(&sc->sc_ad_tmo);
callout_stop(&sc->sc_md_tmo);
callout_stop(&sc->sc_md6_tmo);
carp_set_state(sc, INIT);
carp_setrun(sc, 0);
if (!sc->sc_suppress) {
carp_suppress_preempt++;
if (carp_suppress_preempt == 1) {
CARP_SCUNLOCK(sc);
carp_send_ad_all();
CARP_SCLOCK(sc);
}
}
sc->sc_suppress = 1;
} else {
SC2IFP(sc)->if_flags |= sc->sc_flags_backup;
carp_set_state(sc, INIT);
carp_setrun(sc, 0);
if (sc->sc_suppress)
carp_suppress_preempt--;
sc->sc_suppress = 0;
}
return;
}
static int
carp_modevent(module_t mod, int type, void *data)
{
switch (type) {
case MOD_LOAD:
if_detach_event_tag = EVENTHANDLER_REGISTER(ifnet_departure_event,
carp_ifdetach, NULL, EVENTHANDLER_PRI_ANY);
if (if_detach_event_tag == NULL)
return (ENOMEM);
mtx_init(&carp_mtx, "carp_mtx", NULL, MTX_DEF);
LIST_INIT(&carpif_list);
if_clone_attach(&carp_cloner);
break;
case MOD_UNLOAD:
EVENTHANDLER_DEREGISTER(ifnet_departure_event, if_detach_event_tag);
if_clone_detach(&carp_cloner);
mtx_destroy(&carp_mtx);
break;
default:
return (EINVAL);
}
return (0);
}
static moduledata_t carp_mod = {
"carp",
carp_modevent,
0
};
DECLARE_MODULE(carp, carp_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);