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NetBSD/sys/netinet6/nd6_nbr.c

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/* $NetBSD: nd6_nbr.c,v 1.183 2023/03/29 13:01:44 kardel Exp $ */
/* $KAME: nd6_nbr.c,v 1.61 2001/02/10 16:06:14 jinmei Exp $ */
/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* 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.
* 3. Neither the name of the project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``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 PROJECT OR CONTRIBUTORS 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 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 <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: nd6_nbr.c,v 1.183 2023/03/29 13:01:44 kardel Exp $");
#ifdef _KERNEL_OPT
#include "opt_inet.h"
#include "opt_net_mpsafe.h"
#endif
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kmem.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sockio.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/errno.h>
#include <sys/ioctl.h>
#include <sys/syslog.h>
#include <sys/queue.h>
#include <sys/callout.h>
#include <sys/cprng.h>
#include <net/if.h>
#include <net/if_types.h>
#include <net/if_dl.h>
#include <net/if_llatbl.h>
#include <net/nd.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet6/in6_var.h>
#include <netinet6/in6_ifattach.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/scope6_var.h>
#include <netinet6/nd6.h>
#include <netinet/icmp6.h>
#include <netinet6/icmp6_private.h>
#include "carp.h"
#if NCARP > 0
#include <netinet/ip_carp.h>
#endif
struct dadq;
static struct dadq *nd6_dad_find(struct ifaddr *, struct nd_opt_nonce *, bool *);
static bool nd6_dad_ownnonce(struct ifaddr *, struct nd_opt_nonce *nonce);
static void nd6_dad_starttimer(struct dadq *, int);
static void nd6_dad_destroytimer(struct dadq *);
static void nd6_dad_timer(struct dadq *);
static void nd6_dad_ns_output(struct dadq *, struct ifaddr *);
static void nd6_dad_input(struct ifaddr *, struct nd_opt_nonce *,
const struct sockaddr_dl *);
static void nd6_dad_duplicated(struct ifaddr *, struct dadq *,
const struct sockaddr_dl *);
static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */
/*
* Input a Neighbor Solicitation Message.
*
* Based on RFC 2461
* Based on RFC 2462 (duplicate address detection)
*/
void
nd6_ns_input(struct mbuf *m, int off, int icmp6len)
{
struct ifnet *ifp, *ifpc;
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
struct nd_neighbor_solicit *nd_ns;
struct in6_addr saddr6 = ip6->ip6_src;
struct in6_addr daddr6 = ip6->ip6_dst;
struct in6_addr taddr6;
struct in6_addr myaddr6;
char *lladdr = NULL;
struct ifaddr *ifa = NULL;
int lladdrlen = 0;
int anycast = 0, proxy = 0, tentative = 0;
int router = ip6_forwarding;
int tlladdr;
union nd_opts ndopts;
const struct sockaddr_dl *proxydl = NULL;
struct psref psref;
struct psref psref_c;
struct psref psref_ia;
char ip6buf[INET6_ADDRSTRLEN], ip6buf2[INET6_ADDRSTRLEN];
ifp = ifpc = m_get_rcvif_psref(m, &psref);
if (ifp == NULL)
goto freeit;
IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len);
if (nd_ns == NULL) {
ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
m_put_rcvif_psref(ifp, &psref);
return;
}
ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */
taddr6 = nd_ns->nd_ns_target;
if (in6_setscope(&taddr6, ifp, NULL) != 0)
goto bad;
if (ip6->ip6_hlim != 255) {
nd6log(LOG_ERR, "invalid hlim (%d) from %s to %s on %s\n",
ip6->ip6_hlim, IN6_PRINT(ip6buf, &ip6->ip6_src),
IN6_PRINT(ip6buf2, &ip6->ip6_dst), if_name(ifp));
goto bad;
}
if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
/* dst has to be a solicited node multicast address. */
/* don't check ifindex portion */
if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL &&
daddr6.s6_addr32[1] == 0 &&
daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE &&
daddr6.s6_addr8[12] == 0xff) {
; /* good */
} else {
nd6log(LOG_INFO, "bad DAD packet (wrong ip6 dst)\n");
goto bad;
}
} else {
struct sockaddr_in6 ssin6;
/*
* Make sure the source address is from a neighbor's address.
*/
sockaddr_in6_init(&ssin6, &saddr6, 0, 0, 0);
if (nd6_is_addr_neighbor(&ssin6, ifp) == 0) {
nd6log(LOG_INFO,
"NS packet from non-neighbor %s on %s\n",
IN6_PRINT(ip6buf, &saddr6), if_name(ifp));
goto bad;
}
}
if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
nd6log(LOG_INFO, "bad NS target (multicast)\n");
goto bad;
}
icmp6len -= sizeof(*nd_ns);
nd6_option_init(nd_ns + 1, icmp6len, &ndopts);
if (nd6_options(&ndopts) < 0) {
nd6log(LOG_INFO, "invalid ND option, ignored\n");
/* nd6_options have incremented stats */
goto freeit;
}
if (ndopts.nd_opts_src_lladdr) {
lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
}
if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) {
nd6log(LOG_INFO,
"bad DAD packet (link-layer address option)\n");
goto bad;
}
/*
* Attaching target link-layer address to the NA?
* (RFC 2461 7.2.4)
*
* NS IP dst is multicast MUST add
* Otherwise MAY be omitted
*
* In this implementation, we omit the target link-layer address
* in the "MAY" case.
*/
#if 0 /* too much! */
ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6);
if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST))
tlladdr = 0;
else
#endif
if (!IN6_IS_ADDR_MULTICAST(&daddr6))
tlladdr = 0;
else
tlladdr = 1;
/*
* Target address (taddr6) must be either:
* (1) Valid unicast/anycast address for my receiving interface,
* (2) Unicast address for which I'm offering proxy service, or
* (3) "tentative" address on which DAD is being performed.
*/
/* (1) and (3) check. */
#if NCARP > 0
if (ifp->if_carp && ifp->if_type != IFT_CARP) {
int s = pserialize_read_enter();
ifa = carp_iamatch6(ifp->if_carp, &taddr6);
if (ifa != NULL) {
ifa_acquire(ifa, &psref_ia);
if (ifa->ifa_ifp && ifa->ifa_ifp != ifp) {
ifpc = ifa->ifa_ifp;
if_acquire(ifpc, &psref_c);
}
}
pserialize_read_exit(s);
} else
ifa = NULL;
if (!ifa)
ifa = (struct ifaddr *)in6ifa_ifpwithaddr_psref(ifp, &taddr6,
&psref_ia);
#else
ifa = (struct ifaddr *)in6ifa_ifpwithaddr_psref(ifp, &taddr6,
&psref_ia);
#endif
/* (2) check. */
if (ifa == NULL) {
struct rtentry *rt;
struct sockaddr_in6 tsin6;
sockaddr_in6_init(&tsin6, &taddr6, 0, 0, 0);
rt = rtalloc1(sin6tosa(&tsin6), 0);
if (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 &&
rt->rt_gateway->sa_family == AF_LINK) {
/*
* proxy NDP for single entry
*/
ifa = (struct ifaddr *)in6ifa_ifpforlinklocal_psref(ifp,
IN6_IFF_NOTREADY|IN6_IFF_ANYCAST, &psref_ia);
if (ifa) {
proxy = 1;
proxydl = satocsdl(rt->rt_gateway);
router = 0; /* XXX */
}
}
if (rt)
rt_unref(rt);
}
if (ifa == NULL) {
/*
* We've got an NS packet, and we don't have that address
* assigned for us. We MUST silently ignore it.
* See RFC2461 7.2.3.
*/
goto freeit;
}
myaddr6 = *IFA_IN6(ifa);
anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST;
tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE;
if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED)
goto freeit;
if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
nd6log(LOG_INFO, "lladdrlen mismatch for %s "
"(if %d, NS packet %d)\n",
IN6_PRINT(ip6buf, &taddr6),
ifp->if_addrlen, lladdrlen - 2);
goto bad;
}
if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) {
nd6log(LOG_INFO, "duplicate IP6 address %s\n",
IN6_PRINT(ip6buf, &saddr6));
goto freeit;
}
/*
* We have neighbor solicitation packet, with target address equals to
* one of my tentative address.
*
* src addr how to process?
* --- ---
* multicast of course, invalid (rejected in ip6_input)
* unicast somebody is doing address resolution -> ignore
* unspec dup address detection
*
* The processing is defined in RFC 2462.
*/
if (tentative) {
/*
* If source address is unspecified address, it is for
* duplicate address detection.
*
* If not, the packet is for address resolution;
* silently ignore it.
*/
if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
struct sockaddr_dl sdl, *sdlp;
if (lladdr != NULL)
sdlp = sockaddr_dl_init(&sdl, sizeof(sdl),
ifp->if_index, ifp->if_type,
NULL, 0, lladdr, lladdrlen);
else
sdlp = NULL;
nd6_dad_input(ifa, ndopts.nd_opts_nonce, sdlp);
}
goto freeit;
}
/*
* It looks that sender is performing DAD.
* Check that the nonce is not being used by the same address
* on another interface.
*/
if (IN6_IS_ADDR_UNSPECIFIED(&saddr6) && ndopts.nd_opts_nonce != NULL) {
if (nd6_dad_ownnonce(ifa, ndopts.nd_opts_nonce))
goto freeit;
}
ifa_release(ifa, &psref_ia);
ifa = NULL;
/*
* If the source address is unspecified address, entries must not
* be created or updated.
* It looks that sender is performing DAD. Output NA toward
* all-node multicast address, to tell the sender that I'm using
* the address.
* S bit ("solicited") must be zero.
*/
if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) {
struct in6_addr in6_all;
in6_all = in6addr_linklocal_allnodes;
if (in6_setscope(&in6_all, ifp, NULL) != 0)
goto bad;
nd6_na_output(ifpc, &in6_all, &taddr6,
((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
(ip6_forwarding ? ND_NA_FLAG_ROUTER : 0),
tlladdr, (const struct sockaddr *)proxydl);
goto freeit;
}
nd6_cache_lladdr(ifpc, &saddr6, lladdr, lladdrlen, ND_NEIGHBOR_SOLICIT, 0);
nd6_na_output(ifp, &saddr6, &taddr6,
((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) |
(router ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED,
tlladdr, (const struct sockaddr *)proxydl);
freeit:
ifa_release(ifa, &psref_ia);
m_put_rcvif_psref(ifp, &psref);
if (ifp != ifpc)
if_put(ifpc, &psref_c);
m_freem(m);
return;
bad:
nd6log(LOG_ERR, "src=%s\n", IN6_PRINT(ip6buf, &saddr6));
nd6log(LOG_ERR, "dst=%s\n", IN6_PRINT(ip6buf, &daddr6));
nd6log(LOG_ERR, "tgt=%s\n", IN6_PRINT(ip6buf, &taddr6));
ICMP6_STATINC(ICMP6_STAT_BADNS);
ifa_release(ifa, &psref_ia);
m_put_rcvif_psref(ifp, &psref);
m_freem(m);
}
/*
* Output a Neighbor Solicitation Message. Caller specifies:
* - ICMP6 header source IP6 address
* - ND6 header target IP6 address
* - ND6 header source datalink address
*
* Based on RFC 2461
* Based on RFC 2462 (duplicate address detection)
*/
void
nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6,
const struct in6_addr *taddr6,
const struct in6_addr *hsrc,
const uint8_t *nonce /* duplicate address detection */)
{
struct mbuf *m;
struct ip6_hdr *ip6;
struct nd_neighbor_solicit *nd_ns;
const struct in6_addr *src;
struct in6_addr src_in;
struct ip6_moptions im6o;
int icmp6len;
int maxlen;
const void *mac;
struct route ro;
if (IN6_IS_ADDR_MULTICAST(taddr6))
return;
memset(&ro, 0, sizeof(ro));
/* estimate the size of message */
maxlen = sizeof(*ip6) + sizeof(*nd_ns);
maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
KASSERTMSG(max_linkhdr + maxlen <= MCLBYTES,
"max_linkhdr + maxlen > MCLBYTES (%d + %d > %d)",
max_linkhdr, maxlen, MCLBYTES);
MGETHDR(m, M_DONTWAIT, MT_DATA);
if (m && max_linkhdr + maxlen >= MHLEN) {
MCLGET(m, M_DONTWAIT);
if ((m->m_flags & M_EXT) == 0) {
m_free(m);
m = NULL;
}
}
if (m == NULL)
return;
m_reset_rcvif(m);
if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) {
m->m_flags |= M_MCAST;
im6o.im6o_multicast_if_index = if_get_index(ifp);
im6o.im6o_multicast_hlim = 255;
im6o.im6o_multicast_loop = 0;
}
icmp6len = sizeof(*nd_ns);
m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len;
m->m_data += max_linkhdr; /* or m_align() equivalent? */
/* fill neighbor solicitation packet */
ip6 = mtod(m, struct ip6_hdr *);
ip6->ip6_flow = 0;
ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
ip6->ip6_vfc |= IPV6_VERSION;
/* ip6->ip6_plen will be set later */
ip6->ip6_nxt = IPPROTO_ICMPV6;
ip6->ip6_hlim = 255;
if (daddr6)
ip6->ip6_dst = *daddr6;
else {
ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
ip6->ip6_dst.s6_addr16[1] = 0;
ip6->ip6_dst.s6_addr32[1] = 0;
ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE;
ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3];
ip6->ip6_dst.s6_addr8[12] = 0xff;
if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0)
goto bad;
}
if (nonce == NULL) {
int s;
/*
* RFC2461 7.2.2:
* "If the source address of the packet prompting the
* solicitation is the same as one of the addresses assigned
* to the outgoing interface, that address SHOULD be placed
* in the IP Source Address of the outgoing solicitation.
* Otherwise, any one of the addresses assigned to the
* interface should be used."
*
* We use the source address for the prompting packet
* (hsrc), if:
* - hsrc is given from the caller (by giving "ln"), and
* - hsrc belongs to the outgoing interface.
* Otherwise, we perform the source address selection as usual.
*/
s = pserialize_read_enter();
if (hsrc && in6ifa_ifpwithaddr(ifp, hsrc)) {
pserialize_read_exit(s);
src = hsrc;
} else {
int error;
struct sockaddr_in6 dst_sa;
pserialize_read_exit(s);
sockaddr_in6_init(&dst_sa, &ip6->ip6_dst, 0, 0, 0);
error = in6_selectsrc(&dst_sa, NULL,
NULL, &ro, NULL, NULL, NULL, &src_in);
if (error != 0) {
char ip6buf[INET6_ADDRSTRLEN];
nd6log(LOG_DEBUG, "source can't be "
"determined: dst=%s, error=%d\n",
IN6_PRINT(ip6buf, &dst_sa.sin6_addr),
error);
goto bad;
}
src = &src_in;
}
} else {
/*
* Source address for DAD packet must always be IPv6
* unspecified address. (0::0)
* We actually don't have to 0-clear the address (we did it
* above), but we do so here explicitly to make the intention
* clearer.
*/
memset(&src_in, 0, sizeof(src_in));
src = &src_in;
}
ip6->ip6_src = *src;
nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1);
nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT;
nd_ns->nd_ns_code = 0;
nd_ns->nd_ns_reserved = 0;
nd_ns->nd_ns_target = *taddr6;
in6_clearscope(&nd_ns->nd_ns_target); /* XXX */
/*
* Add source link-layer address option.
*
* spec implementation
* --- ---
* DAD packet MUST NOT do not add the option
* there's no link layer address:
* impossible do not add the option
* there's link layer address:
* Multicast NS MUST add one add the option
* Unicast NS SHOULD add one add the option
*/
if (nonce == NULL && (mac = nd6_ifptomac(ifp))) {
int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
/* 8 byte alignments... */
optlen = (optlen + 7) & ~7;
m->m_pkthdr.len += optlen;
m->m_len += optlen;
icmp6len += optlen;
memset((void *)nd_opt, 0, optlen);
nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR;
nd_opt->nd_opt_len = optlen >> 3;
memcpy((void *)(nd_opt + 1), mac, ifp->if_addrlen);
}
/* Add a nonce option (RFC 3971) to detect looped back NS messages.
* This behavior is documented in RFC 7527. */
if (nonce != NULL) {
int optlen = sizeof(struct nd_opt_hdr) + ND_OPT_NONCE_LEN;
struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1);
/* 8-byte alignment is required. */
optlen = (optlen + 7) & ~7;
m->m_pkthdr.len += optlen;
m->m_len += optlen;
icmp6len += optlen;
memset(nd_opt, 0, optlen);
nd_opt->nd_opt_type = ND_OPT_NONCE;
nd_opt->nd_opt_len = optlen >> 3;
memcpy(nd_opt + 1, nonce, ND_OPT_NONCE_LEN);
}
ip6->ip6_plen = htons((u_int16_t)icmp6len);
nd_ns->nd_ns_cksum = 0;
nd_ns->nd_ns_cksum =
in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len);
ip6_output(m, NULL, &ro, nonce != NULL ? IPV6_UNSPECSRC : 0,
&im6o, NULL, NULL);
icmp6_ifstat_inc(ifp, ifs6_out_msg);
icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit);
ICMP6_STATINC(ICMP6_STAT_OUTHIST + ND_NEIGHBOR_SOLICIT);
rtcache_free(&ro);
return;
bad:
rtcache_free(&ro);
m_freem(m);
return;
}
/*
* Neighbor advertisement input handling.
*
* Based on RFC 2461
* Based on RFC 2462 (duplicate address detection)
*
* the following items are not implemented yet:
* - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
* - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
*/
void
nd6_na_input(struct mbuf *m, int off, int icmp6len)
{
struct ifnet *ifp;
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
struct nd_neighbor_advert *nd_na;
struct in6_addr saddr6 = ip6->ip6_src;
struct in6_addr daddr6 = ip6->ip6_dst;
struct in6_addr taddr6;
int flags;
int is_router;
int is_solicited;
int is_override;
int rt_cmd;
char *lladdr = NULL;
int lladdrlen = 0;
struct ifaddr *ifa;
struct llentry *ln = NULL;
union nd_opts ndopts;
struct sockaddr_in6 ssin6;
struct psref psref;
struct psref psref_ia;
char ip6buf[INET6_ADDRSTRLEN], ip6buf2[INET6_ADDRSTRLEN];
ifp = m_get_rcvif_psref(m, &psref);
if (ifp == NULL)
goto freeit;
if (ip6->ip6_hlim != 255) {
nd6log(LOG_ERR,
"invalid hlim (%d) from %s to %s on %s\n",
ip6->ip6_hlim, IN6_PRINT(ip6buf, &ip6->ip6_src),
IN6_PRINT(ip6buf2, &ip6->ip6_dst), if_name(ifp));
goto bad;
}
IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len);
if (nd_na == NULL) {
m_put_rcvif_psref(ifp, &psref);
ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
return;
}
flags = nd_na->nd_na_flags_reserved;
is_router = ((flags & ND_NA_FLAG_ROUTER) != 0);
is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0);
is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0);
taddr6 = nd_na->nd_na_target;
if (in6_setscope(&taddr6, ifp, NULL)) {
goto bad;
}
if (IN6_IS_ADDR_MULTICAST(&taddr6)) {
nd6log(LOG_ERR, "invalid target address %s\n",
IN6_PRINT(ip6buf, &taddr6));
goto bad;
}
if (is_solicited && IN6_IS_ADDR_MULTICAST(&daddr6)) {
nd6log(LOG_ERR, "a solicited adv is multicasted\n");
goto bad;
}
icmp6len -= sizeof(*nd_na);
nd6_option_init(nd_na + 1, icmp6len, &ndopts);
if (nd6_options(&ndopts) < 0) {
nd6log(LOG_INFO, "invalid ND option, ignored\n");
/* nd6_options have incremented stats */
goto freeit;
}
if (ndopts.nd_opts_tgt_lladdr != NULL) {
struct ifnet *ifp_ll;
struct psref psref_ll;
lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
nd6log(LOG_INFO, "lladdrlen mismatch for %s "
"(if %d, NA packet %d)\n", IN6_PRINT(ip6buf, &taddr6),
ifp->if_addrlen, lladdrlen - 2);
goto bad;
}
ifp_ll = if_get_bylla(lladdr, ifp->if_addrlen, &psref_ll);
if (ifp_ll != NULL) {
/* it's from me, ignore it. */
if_put(ifp_ll, &psref_ll);
goto freeit;
}
}
ifa = (struct ifaddr *)in6ifa_ifpwithaddr_psref(ifp, &taddr6, &psref_ia);
/*
* Target address matches one of my interface address.
*
* If my address is tentative, this means that there's somebody
* already using the same address as mine. This indicates DAD failure.
* This is defined in RFC 2462.
*
* Otherwise, process as defined in RFC 2461.
*/
if (ifa) {
if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE) {
struct sockaddr_dl sdl, *sdlp;
if (lladdr != NULL)
sdlp = sockaddr_dl_init(&sdl, sizeof(sdl),
ifp->if_index, ifp->if_type,
NULL, 0, lladdr, lladdrlen);
else
sdlp = NULL;
nd6_dad_input(ifa, NULL, sdlp);
} else
log(LOG_ERR,
"nd6_na_input: duplicate IP6 address %s\n",
IN6_PRINT(ip6buf, &taddr6));
ifa_release(ifa, &psref_ia);
ifa = NULL;
goto freeit;
}
/*
* Make sure the source address is from a neighbor's address.
*/
sockaddr_in6_init(&ssin6, &saddr6, 0, 0, 0);
if (nd6_is_addr_neighbor(&ssin6, ifp) == 0) {
nd6log(LOG_INFO, "ND packet from non-neighbor %s on %s\n",
IN6_PRINT(ip6buf, &saddr6), if_name(ifp));
goto bad;
}
/*
* If no neighbor cache entry is found, NA SHOULD silently be
* discarded.
*/
ln = nd6_lookup(&taddr6, ifp, true);
if (ln == NULL)
goto freeit;
rt_cmd = 0;
if (ln->ln_state <= ND_LLINFO_INCOMPLETE) {
/*
* If the link-layer has address, and no lladdr option came,
* discard the packet.
*/
if (ifp->if_addrlen && !lladdr)
goto freeit;
/*
* Record link-layer address, and update the state.
*/
memcpy(&ln->ll_addr, lladdr, ifp->if_addrlen);
ln->la_flags |= LLE_VALID;
rt_cmd = RTM_ADD;
if (is_solicited) {
ln->ln_state = ND_LLINFO_REACHABLE;
ln->ln_byhint = 0;
if (!ND_IS_LLINFO_PERMANENT(ln))
nd_set_timer(ln, ND_TIMER_REACHABLE);
} else {
ln->ln_state = ND_LLINFO_STALE;
nd_set_timer(ln, ND_TIMER_GC);
}
} else {
bool llchange;
/*
* Check if the link-layer address has changed or not.
*/
if (lladdr == NULL)
llchange = false;
else {
if (ln->la_flags & LLE_VALID) {
if (memcmp(lladdr, &ln->ll_addr, ifp->if_addrlen))
llchange = true;
else
llchange = false;
} else
llchange = true;
}
if (llchange)
rt_cmd = RTM_CHANGE;
/*
* This is VERY complex. Look at it with care.
*
* override solicit lladdr llchange action
* (L: record lladdr)
*
* 0 0 n -- (2c)
* 0 0 y n (2b) L
* 0 0 y y (1) REACHABLE->STALE
* 0 1 n -- (2c) *->REACHABLE
* 0 1 y n (2b) L *->REACHABLE
* 0 1 y y (1) REACHABLE->STALE
* 1 0 n -- (2a)
* 1 0 y n (2a) L
* 1 0 y y (2a) L *->STALE
* 1 1 n -- (2a) *->REACHABLE
* 1 1 y n (2a) L *->REACHABLE
* 1 1 y y (2a) L *->REACHABLE
*/
if (!is_override && lladdr != NULL && llchange) { /* (1) */
/*
* If state is REACHABLE, make it STALE.
* no other updates should be done.
*/
if (ln->ln_state == ND_LLINFO_REACHABLE) {
ln->ln_state = ND_LLINFO_STALE;
nd_set_timer(ln, ND_TIMER_GC);
}
goto freeit;
} else if (is_override /* (2a) */
|| (!is_override && lladdr != NULL && !llchange) /* (2b) */
|| lladdr == NULL) { /* (2c) */
/*
* Update link-local address, if any.
*/
if (lladdr != NULL) {
memcpy(&ln->ll_addr, lladdr, ifp->if_addrlen);
ln->la_flags |= LLE_VALID;
}
/*
* If solicited, make the state REACHABLE.
* If not solicited and the link-layer address was
* changed, make it STALE.
*/
if (is_solicited) {
ln->ln_state = ND_LLINFO_REACHABLE;
ln->ln_byhint = 0;
if (!ND_IS_LLINFO_PERMANENT(ln))
nd_set_timer(ln, ND_TIMER_REACHABLE);
} else {
if (lladdr && llchange) {
ln->ln_state = ND_LLINFO_STALE;
nd_set_timer(ln, ND_TIMER_GC);
}
}
}
ln->ln_router = is_router;
}
/*
* XXX: does this matter?
* rt->rt_flags &= ~RTF_REJECT;
*/
ln->ln_asked = 0;
nd6_llinfo_release_pkts(ln, ifp);
if (rt_cmd != 0) {
struct sockaddr_in6 sin6;
sockaddr_in6_init(&sin6, &ln->r_l3addr.addr6, 0, 0, 0);
rt_clonedmsg(rt_cmd, sin6tosa(&ssin6), sin6tosa(&sin6),
(char *)&ln->ll_addr, ln->lle_tbl->llt_ifp);
}
freeit:
if (ln != NULL)
LLE_WUNLOCK(ln);
m_put_rcvif_psref(ifp, &psref);
m_freem(m);
return;
bad:
if (ln != NULL)
LLE_WUNLOCK(ln);
ICMP6_STATINC(ICMP6_STAT_BADNA);
m_put_rcvif_psref(ifp, &psref);
m_freem(m);
}
/*
* Neighbor advertisement output handling.
*
* Based on RFC 2461
*
* the following items are not implemented yet:
* - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD)
* - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD)
*/
void
nd6_na_output(
struct ifnet *ifp,
const struct in6_addr *daddr6_0,
const struct in6_addr *taddr6,
u_long flags,
int tlladdr, /* 1 if include target link-layer address */
const struct sockaddr *sdl0) /* sockaddr_dl (= proxy NA) or NULL */
{
struct mbuf *m;
struct ip6_hdr *ip6;
struct nd_neighbor_advert *nd_na;
struct ip6_moptions im6o;
struct sockaddr *dst;
union {
struct sockaddr dst;
struct sockaddr_in6 dst6;
} u;
struct in6_addr daddr6;
int icmp6len, maxlen, error;
const void *mac;
struct route ro;
mac = NULL;
memset(&ro, 0, sizeof(ro));
daddr6 = *daddr6_0; /* make a local copy for modification */
/* estimate the size of message */
maxlen = sizeof(*ip6) + sizeof(*nd_na);
maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7;
KASSERTMSG(max_linkhdr + maxlen <= MCLBYTES,
"max_linkhdr + maxlen > MCLBYTES (%d + %d > %d)",
max_linkhdr, maxlen, MCLBYTES);
MGETHDR(m, M_DONTWAIT, MT_DATA);
if (m && max_linkhdr + maxlen >= MHLEN) {
MCLGET(m, M_DONTWAIT);
if ((m->m_flags & M_EXT) == 0) {
m_free(m);
m = NULL;
}
}
if (m == NULL)
return;
m_reset_rcvif(m);
if (IN6_IS_ADDR_MULTICAST(&daddr6)) {
m->m_flags |= M_MCAST;
im6o.im6o_multicast_if_index = if_get_index(ifp);
im6o.im6o_multicast_hlim = 255;
im6o.im6o_multicast_loop = 0;
}
icmp6len = sizeof(*nd_na);
m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len;
m->m_data += max_linkhdr; /* or m_align() equivalent? */
/* fill neighbor advertisement packet */
ip6 = mtod(m, struct ip6_hdr *);
ip6->ip6_flow = 0;
ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
ip6->ip6_vfc |= IPV6_VERSION;
ip6->ip6_nxt = IPPROTO_ICMPV6;
ip6->ip6_hlim = 255;
if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) {
/* reply to DAD */
daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL;
daddr6.s6_addr16[1] = 0;
daddr6.s6_addr32[1] = 0;
daddr6.s6_addr32[2] = 0;
daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE;
if (in6_setscope(&daddr6, ifp, NULL))
goto bad;
flags &= ~ND_NA_FLAG_SOLICITED;
}
ip6->ip6_dst = daddr6;
sockaddr_in6_init(&u.dst6, &daddr6, 0, 0, 0);
dst = &u.dst;
if (rtcache_setdst(&ro, dst) != 0)
goto bad;
/*
* Select a source whose scope is the same as that of the dest.
*/
error = in6_selectsrc(satosin6(dst), NULL, NULL, &ro, NULL, NULL, NULL,
&ip6->ip6_src);
if (error != 0) {
char ip6buf[INET6_ADDRSTRLEN];
nd6log(LOG_DEBUG, "source can't be "
"determined: dst=%s, error=%d\n",
IN6_PRINT(ip6buf, &satocsin6(dst)->sin6_addr), error);
goto bad;
}
nd_na = (struct nd_neighbor_advert *)(ip6 + 1);
nd_na->nd_na_type = ND_NEIGHBOR_ADVERT;
nd_na->nd_na_code = 0;
nd_na->nd_na_target = *taddr6;
in6_clearscope(&nd_na->nd_na_target); /* XXX */
/*
* "tlladdr" indicates NS's condition for adding tlladdr or not.
* see nd6_ns_input() for details.
* Basically, if NS packet is sent to unicast/anycast addr,
* target lladdr option SHOULD NOT be included.
*/
if (tlladdr) {
/*
* sdl0 != NULL indicates proxy NA. If we do proxy, use
* lladdr in sdl0. If we are not proxying (sending NA for
* my address) use lladdr configured for the interface.
*/
if (sdl0 == NULL)
mac = nd6_ifptomac(ifp);
else if (sdl0->sa_family == AF_LINK) {
const struct sockaddr_dl *sdl;
sdl = satocsdl(sdl0);
if (sdl->sdl_alen == ifp->if_addrlen)
mac = CLLADDR(sdl);
}
}
if (tlladdr && mac) {
int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen;
struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1);
/* roundup to 8 bytes alignment! */
optlen = (optlen + 7) & ~7;
m->m_pkthdr.len += optlen;
m->m_len += optlen;
icmp6len += optlen;
memset((void *)nd_opt, 0, optlen);
nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
nd_opt->nd_opt_len = optlen >> 3;
memcpy((void *)(nd_opt + 1), mac, ifp->if_addrlen);
} else
flags &= ~ND_NA_FLAG_OVERRIDE;
ip6->ip6_plen = htons((u_int16_t)icmp6len);
nd_na->nd_na_flags_reserved = flags;
nd_na->nd_na_cksum = 0;
nd_na->nd_na_cksum =
in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len);
ip6_output(m, NULL, NULL, 0, &im6o, NULL, NULL);
icmp6_ifstat_inc(ifp, ifs6_out_msg);
icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert);
ICMP6_STATINC(ICMP6_STAT_OUTHIST + ND_NEIGHBOR_ADVERT);
rtcache_free(&ro);
return;
bad:
rtcache_free(&ro);
m_freem(m);
return;
}
const void *
nd6_ifptomac(const struct ifnet *ifp)
{
switch (ifp->if_type) {
case IFT_ARCNET:
case IFT_ETHER:
case IFT_IEEE1394:
case IFT_PROPVIRTUAL:
case IFT_CARP:
case IFT_L2VLAN:
case IFT_IEEE80211:
return CLLADDR(ifp->if_sadl);
default:
return NULL;
}
}
TAILQ_HEAD(dadq_head, dadq);
struct dadq {
TAILQ_ENTRY(dadq) dad_list;
struct ifaddr *dad_ifa;
int dad_count; /* max NS to send */
int dad_ns_tcount; /* # of trials to send NS */
int dad_ns_ocount; /* NS sent so far */
int dad_ns_lcount; /* looped back NS */
struct callout dad_timer_ch;
#define ND_OPT_NONCE_STORE 3 /* dad_count should not exceed this */
/*
* The default ip6_dad_count is 1 as specified by RFC 4862 and
* practically must users won't exceed this.
* A storage of 3 is defaulted to here, in-case the administrator wants
* to match the equivalent behaviour in our ARP implementation.
* This constraint could be removed by sending the on wire nonce as
* hmac(key, dad_ns_ocount), but that would increase the nonce size
* sent on the wire.
*/
uint8_t dad_nonce[ND_OPT_NONCE_STORE][ND_OPT_NONCE_LEN];
};
static struct dadq_head dadq;
static kmutex_t nd6_dad_lock;
void
nd6_nbr_init(void)
{
TAILQ_INIT(&dadq);
mutex_init(&nd6_dad_lock, MUTEX_DEFAULT, IPL_NONE);
}
static struct dadq *
nd6_dad_find(struct ifaddr *ifa, struct nd_opt_nonce *nonce, bool *found_nonce)
{
struct in6_addr *myaddr6, *dadaddr6;
bool match_ifa;
struct dadq *dp;
int i, nonce_max;
KASSERT(mutex_owned(&nd6_dad_lock));
KASSERT(ifa != NULL);
myaddr6 = IFA_IN6(ifa);
if (nonce != NULL &&
nonce->nd_opt_nonce_len != (ND_OPT_NONCE_LEN + 2) / 8)
nonce = NULL;
match_ifa = nonce == NULL || found_nonce == NULL || *found_nonce == false;
if (found_nonce != NULL)
*found_nonce = false;
TAILQ_FOREACH(dp, &dadq, dad_list) {
if (match_ifa) {
if (dp->dad_ifa != ifa)
continue;
} else {
dadaddr6 = IFA_IN6(dp->dad_ifa);
if (!IN6_ARE_ADDR_EQUAL(myaddr6, dadaddr6))
continue;
}
if (nonce == NULL)
break;
nonce_max = MIN(dp->dad_ns_ocount, ND_OPT_NONCE_STORE);
for (i = 0; i < nonce_max; i++) {
if (memcmp(nonce->nd_opt_nonce,
dp->dad_nonce[i],
ND_OPT_NONCE_LEN) == 0)
break;
}
if (i < nonce_max) {
char ip6buf[INET6_ADDRSTRLEN];
*found_nonce = true;
log(LOG_DEBUG,
"%s: detected a looped back NS message for %s\n",
if_name(ifa->ifa_ifp), IN6_PRINT(ip6buf, myaddr6));
dp->dad_ns_lcount++;
continue;
}
break;
}
return dp;
}
static bool
nd6_dad_ownnonce(struct ifaddr *ifa, struct nd_opt_nonce *nonce)
{
bool found_nonce = true;
mutex_enter(&nd6_dad_lock);
nd6_dad_find(ifa, nonce, &found_nonce);
mutex_exit(&nd6_dad_lock);
return found_nonce;
}
static void
nd6_dad_starttimer(struct dadq *dp, int ticks)
{
callout_reset(&dp->dad_timer_ch, ticks,
(void (*)(void *))nd6_dad_timer, dp);
}
static void
nd6_dad_stoptimer(struct dadq *dp)
{
KASSERT(mutex_owned(&nd6_dad_lock));
TAILQ_REMOVE(&dadq, dp, dad_list);
/* Tell the timer that dp is being destroyed. */
dp->dad_ifa = NULL;
callout_halt(&dp->dad_timer_ch, &nd6_dad_lock);
}
static void
nd6_dad_destroytimer(struct dadq *dp)
{
KASSERT(dp->dad_ifa == NULL);
callout_destroy(&dp->dad_timer_ch);
kmem_intr_free(dp, sizeof(*dp));
}
/*
* Start Duplicate Address Detection (DAD) for specified interface address.
*
* Note that callout is used when xtick > 0 and not when xtick == 0.
*
* xtick: minimum delay ticks for IFF_UP event
*/
void
nd6_dad_start(struct ifaddr *ifa, int xtick)
{
struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
struct dadq *dp;
char ip6buf[INET6_ADDRSTRLEN];
/*
* If we don't need DAD, don't do it.
* There are several cases:
* - DAD is disabled
* - the interface address is anycast
*/
if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) {
log(LOG_DEBUG,
"nd6_dad_start: called with non-tentative address "
"%s(%s)\n",
IN6_PRINT(ip6buf, &ia->ia_addr.sin6_addr),
if_name(ifa->ifa_ifp));
return;
}
if (ia->ia6_flags & IN6_IFF_ANYCAST || !ip6_dad_enabled()) {
ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
rt_addrmsg(RTM_NEWADDR, ifa);
return;
}
if (!(ifa->ifa_ifp->if_flags & IFF_UP))
return;
dp = kmem_intr_alloc(sizeof(*dp), KM_NOSLEEP);
mutex_enter(&nd6_dad_lock);
if (nd6_dad_find(ifa, NULL, NULL) != NULL) {
mutex_exit(&nd6_dad_lock);
/* DAD already in progress */
if (dp != NULL)
kmem_intr_free(dp, sizeof(*dp));
return;
}
if (dp == NULL) {
mutex_exit(&nd6_dad_lock);
log(LOG_ERR, "nd6_dad_start: memory allocation failed for "
"%s(%s)\n",
IN6_PRINT(ip6buf, &ia->ia_addr.sin6_addr),
if_name(ifa->ifa_ifp));
return;
}
/*
* Send NS packet for DAD, ip6_dad_count times.
* Note that we must delay the first transmission, if this is the
* first packet to be sent from the interface after interface
* (re)initialization.
*/
callout_init(&dp->dad_timer_ch, CALLOUT_MPSAFE);
dp->dad_ifa = ifa;
ifaref(ifa); /* just for safety */
dp->dad_count = ip6_dad_count;
dp->dad_ns_ocount = dp->dad_ns_tcount = 0;
dp->dad_ns_lcount = 0;
TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list);
nd6log(LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp),
IN6_PRINT(ip6buf, &ia->ia_addr.sin6_addr));
if (xtick == 0) {
nd6_dad_ns_output(dp, ifa);
nd6_dad_starttimer(dp,
(long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
} else
nd6_dad_starttimer(dp, xtick);
mutex_exit(&nd6_dad_lock);
}
/*
* terminate DAD unconditionally. used for address removals.
*/
void
nd6_dad_stop(struct ifaddr *ifa)
{
struct dadq *dp;
mutex_enter(&nd6_dad_lock);
dp = nd6_dad_find(ifa, NULL, NULL);
if (dp == NULL) {
mutex_exit(&nd6_dad_lock);
/* DAD wasn't started yet */
return;
}
/* Prevent the timer from running anymore. */
nd6_dad_stoptimer(dp);
mutex_exit(&nd6_dad_lock);
nd6_dad_destroytimer(dp);
ifafree(ifa);
}
static void
nd6_dad_timer(struct dadq *dp)
{
struct ifaddr *ifa;
struct in6_ifaddr *ia;
char ip6buf[INET6_ADDRSTRLEN];
bool need_free = false;
KERNEL_LOCK_UNLESS_NET_MPSAFE();
mutex_enter(&nd6_dad_lock);
ifa = dp->dad_ifa;
if (ifa == NULL) {
/* dp is being destroyed by someone. Do nothing. */
goto done;
}
ia = (struct in6_ifaddr *)ifa;
if (ia->ia6_flags & IN6_IFF_DUPLICATED) {
log(LOG_ERR, "nd6_dad_timer: called with duplicate address "
"%s(%s)\n",
IN6_PRINT(ip6buf, &ia->ia_addr.sin6_addr),
if_name(ifa->ifa_ifp));
goto done;
}
if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) {
log(LOG_ERR, "nd6_dad_timer: called with non-tentative address "
"%s(%s)\n",
IN6_PRINT(ip6buf, &ia->ia_addr.sin6_addr),
if_name(ifa->ifa_ifp));
goto done;
}
/* timeouted with IFF_{RUNNING,UP} check */
if (dp->dad_ns_tcount > dad_maxtry) {
nd6log(LOG_INFO, "%s: could not run DAD, driver problem?\n",
if_name(ifa->ifa_ifp));
nd6_dad_stoptimer(dp);
need_free = true;
goto done;
}
/* Need more checks? */
if (dp->dad_ns_ocount < dp->dad_count) {
/*
* We have more NS to go. Send NS packet for DAD.
*/
nd6_dad_ns_output(dp, ifa);
nd6_dad_starttimer(dp,
(long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000);
} else {
/*
* We are done with DAD. No NA came, no NS came.
* No duplicate address found.
*/
ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
rt_addrmsg(RTM_NEWADDR, ifa);
nd6log(LOG_DEBUG,
"%s: DAD complete for %s - no duplicates found\n",
if_name(ifa->ifa_ifp),
IN6_PRINT(ip6buf, &ia->ia_addr.sin6_addr));
nd6_dad_stoptimer(dp);
need_free = true;
}
done:
mutex_exit(&nd6_dad_lock);
if (need_free) {
nd6_dad_destroytimer(dp);
KASSERT(ifa != NULL);
ifafree(ifa);
}
KERNEL_UNLOCK_UNLESS_NET_MPSAFE();
}
static void
nd6_dad_duplicated(struct ifaddr *ifa, struct dadq *dp,
const struct sockaddr_dl *from)
{
struct in6_ifaddr *ia;
struct ifnet *ifp;
char ip6buf[INET6_ADDRSTRLEN], llabuf[LLA_ADDRSTRLEN], *llastr;
KASSERT(mutex_owned(&nd6_dad_lock));
KASSERT(ifa != NULL);
ifp = ifa->ifa_ifp;
ia = (struct in6_ifaddr *)ifa;
ia->ia6_flags &= ~IN6_IFF_TENTATIVE;
ia->ia6_flags |= IN6_IFF_DUPLICATED;
if (__predict_false(from == NULL))
llastr = NULL;
else
llastr = lla_snprintf(llabuf, sizeof(llabuf),
CLLADDR(from), from->sdl_alen);
log(LOG_ERR, "%s: DAD duplicate address %s from %s\n",
if_name(ifp), IN6_PRINT(ip6buf, &ia->ia_addr.sin6_addr), llastr);
/* Inform the routing socket that DAD has completed */
rt_addrmsg_src(RTM_NEWADDR, ifa, (const struct sockaddr *)from);
/*
* If the address is a link-local address formed from an interface
* identifier based on the hardware address which is supposed to be
* uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP
* operation on the interface SHOULD be disabled.
* [rfc2462bis-03 Section 5.4.5]
*/
if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) {
struct in6_addr in6;
/*
* To avoid over-reaction, we only apply this logic when we are
* very sure that hardware addresses are supposed to be unique.
*/
switch (ifp->if_type) {
case IFT_ETHER:
case IFT_ATM:
case IFT_IEEE1394:
case IFT_IEEE80211:
in6 = ia->ia_addr.sin6_addr;
if (in6_get_hw_ifid(ifp, &in6) == 0 &&
IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) {
ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED;
log(LOG_ERR, "%s: possible hardware address "
"duplication detected, disable IPv6\n",
if_name(ifp));
}
break;
}
}
}
static void
nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa)
{
struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;
struct ifnet *ifp = ifa->ifa_ifp;
uint8_t *nonce;
dp->dad_ns_tcount++;
if ((ifp->if_flags & IFF_UP) == 0) {
#if 0
printf("%s: interface down?\n", if_name(ifp));
#endif
return;
}
if ((ifp->if_flags & IFF_RUNNING) == 0) {
#if 0
printf("%s: interface not running?\n", if_name(ifp));
#endif
return;
}
dp->dad_ns_tcount = 0;
nonce = dp->dad_nonce[dp->dad_ns_ocount % ND_OPT_NONCE_STORE];
cprng_fast(nonce, ND_OPT_NONCE_LEN);
dp->dad_ns_ocount++;
nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, nonce);
}
static void
nd6_dad_input(struct ifaddr *ifa, struct nd_opt_nonce *nonce,
const struct sockaddr_dl *from)
{
struct dadq *dp;
bool found_nonce = false;
KASSERT(ifa != NULL);
mutex_enter(&nd6_dad_lock);
dp = nd6_dad_find(ifa, nonce, &found_nonce);
if (!found_nonce) {
nd6_dad_duplicated(ifa, dp, from);
if (dp != NULL)
nd6_dad_stoptimer(dp);
}
mutex_exit(&nd6_dad_lock);
if (dp != NULL) {
nd6_dad_destroytimer(dp);
ifafree(ifa);
}
}
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