diff --git a/sbin/ifconfig/Makefile b/sbin/ifconfig/Makefile --- a/sbin/ifconfig/Makefile +++ b/sbin/ifconfig/Makefile @@ -24,6 +24,7 @@ .endif .if ${MK_INET6_SUPPORT} != "no" SRCS+= af_nd6.c # ND6 support +SRCS+= ifstf.c # STF configuration options .endif SRCS+= ifclone.c # clone device support diff --git a/sbin/ifconfig/ifstf.c b/sbin/ifconfig/ifstf.c new file mode 100644 --- /dev/null +++ b/sbin/ifconfig/ifstf.c @@ -0,0 +1,152 @@ +/*- + * Copyright 2013 Ermal Luci + * 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 WASABI SYSTEMS, INC. ``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 WASABI SYSTEMS, INC + * 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 +#include +#include +#include + +#include +#include + +#include +#include +#include + +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include +#include + +#include "ifconfig.h" + +static int +do_cmd(int sock, u_long op, void *arg, size_t argsize, int set) +{ + struct ifdrv ifd; + + memset(&ifd, 0, sizeof(ifd)); + + strlcpy(ifd.ifd_name, ifr.ifr_name, sizeof(ifd.ifd_name)); + ifd.ifd_cmd = op; + ifd.ifd_len = argsize; + ifd.ifd_data = arg; + + return (ioctl(sock, set ? SIOCSDRVSPEC : SIOCGDRVSPEC, &ifd)); +} + +static void +stf_status(int s) +{ + struct stfv4args param; + + if (do_cmd(s, STF6RD_GV4NET, ¶m, sizeof(param), 0) < 0) + return; + + printf("\tv4net %s/%d -> ", inet_ntoa(param.srcv4_addr), + param.v4_prefixlen ? param.v4_prefixlen : 32); + printf("tv4br %s\n", inet_ntoa(param.braddr)); +} + +static void +setstf_br(const char *val, int d, int s, const struct afswtch *afp) +{ + struct stfv4args req; + struct sockaddr_in sin; + + memset(&req, 0, sizeof(req)); + + sin.sin_len = sizeof(sin); + sin.sin_family = AF_INET; + + if (!inet_aton(val, &sin.sin_addr)) + errx(1, "%s: bad value", val); + + req.braddr = sin.sin_addr; + if (do_cmd(s, STF6RD_SBR, &req, sizeof(req), 1) < 0) + err(1, "STF6RD_SBR%s", val); +} + +static void +setstf_set(const char *val, int d, int s, const struct afswtch *afp) +{ + struct stfv4args req; + struct sockaddr_in sin; + const char *errstr; + char *p = NULL; + + memset(&req, 0, sizeof(req)); + + sin.sin_len = sizeof(sin); + sin.sin_family = AF_INET; + + p = strrchr(val, '/'); + if (p == NULL) + errx(2, "Wrong argument given"); + + *p = '\0'; + req.v4_prefixlen = (int)strtonum(p + 1, 0, 32, &errstr); + if (errstr != NULL || req.v4_prefixlen == 0) { + *p = '/'; + errx(1, "%s: bad value (prefix length %s)", val, errstr); + } + + if (!inet_aton(val, &sin.sin_addr)) + errx(1, "%s: bad value", val); + + memcpy(&req.srcv4_addr, &sin.sin_addr, sizeof(req.srcv4_addr)); + if (do_cmd(s, STF6RD_SV4NET, &req, sizeof(req), 1) < 0) + err(1, "STF6RD_SV4NET %s", val); +} + +static struct cmd stf_cmds[] = { + DEF_CMD_ARG("stfv4net", setstf_set), + DEF_CMD_ARG("stfv4br", setstf_br), +}; + +static struct afswtch af_stf = { + .af_name = "af_stf", + .af_af = AF_UNSPEC, + .af_other_status = stf_status, +}; + +static __constructor void +stf_ctor(void) +{ + int i; + + for (i = 0; i < nitems(stf_cmds); i++) + cmd_register(&stf_cmds[i]); + af_register(&af_stf); +} diff --git a/sys/net/if_stf.h b/sys/net/if_stf.h new file mode 100644 --- /dev/null +++ b/sys/net/if_stf.h @@ -0,0 +1,46 @@ +/*- + * Copyright (C) 2000 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. + */ + +#ifndef _NET_IF_STF_H_ +#define _NET_IF_STF_H_ + +struct stfv4args { + struct in_addr srcv4_addr; /* Our IPv4 src/WAN address */ + struct in_addr braddr; /* The border relay IPv4 address */ + int v4_prefixlen; /* The length of the IPv4 prefix. (I.e. + the number of bits of the IPv4 + address not encoded in the IPv6 + address. */ +}; + +#define STF6RD_SV4NET 1 +#define STF6RD_GV4NET 2 +#define STF6RD_SBR 3 + +#endif /* _NET_IF_STF_H_ */ diff --git a/sys/net/if_stf.c b/sys/net/if_stf.c --- a/sys/net/if_stf.c +++ b/sys/net/if_stf.c @@ -5,6 +5,9 @@ * SPDX-License-Identifier: BSD-3-Clause * * Copyright (C) 2000 WIDE Project. + * Copyright (c) 2010 Hiroki Sato + * Copyright (c) 2013 Ermal Luci + * Copyright (c) 2017-2021 Rubicon Communications, LLC (Netgate) * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -81,10 +84,12 @@ #include #include #include +#include #include #include #include #include +#include #include #include #include @@ -98,6 +103,7 @@ #include #include #include +#include #include #include @@ -109,6 +115,7 @@ #include #include +#include #include #include #include @@ -141,7 +148,10 @@ struct stf_softc { struct ifnet *sc_ifp; - u_int sc_fibnum; + in_addr_t braddr; /* Border relay IPv4 address */ + in_addr_t srcv4_addr; /* Our IPv4 WAN address */ + u_int v4prefixlen; /* How much of the v4 address to include in our address. */ + u_int sc_fibnum; const struct encaptab *encap_cookie; }; #define STF2IFP(sc) ((sc)->sc_ifp) @@ -164,6 +174,11 @@ struct ifnet *); static int stf_checkaddr6(struct stf_softc *, struct in6_addr *, struct ifnet *); +static struct sockaddr_in *stf_getin4addr_in6(struct stf_softc *, + struct sockaddr_in *, struct in6_addr, struct in6_addr, + struct in6_addr); +static struct sockaddr_in *stf_getin4addr(struct stf_softc *, + struct sockaddr_in *, struct in6_addr, struct in6_addr); static int stf_ioctl(struct ifnet *, u_long, caddr_t); static int stf_clone_match(struct if_clone *, const char *); @@ -324,14 +339,15 @@ }; DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); +MODULE_VERSION(if_stf, 2); static int stf_encapcheck(const struct mbuf *m, int off, int proto, void *arg) { struct ip ip; struct stf_softc *sc; - struct in_addr a, b, mask; struct in6_addr addr6, mask6; + struct sockaddr_in sin4addr, sin4mask; sc = (struct stf_softc *)arg; if (sc == NULL) @@ -355,29 +371,43 @@ if (stf_getsrcifa6(STF2IFP(sc), &addr6, &mask6) != 0) return (0); - /* - * check if IPv4 dst matches the IPv4 address derived from the - * local 6to4 address. - * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... - */ - if (bcmp(GET_V4(&addr6), &ip.ip_dst, sizeof(ip.ip_dst)) != 0) - return (0); + if (sc->srcv4_addr != INADDR_ANY) { + sin4addr.sin_addr.s_addr = sc->srcv4_addr; + sin4addr.sin_family = AF_INET; + } else + if (stf_getin4addr(sc, &sin4addr, addr6, mask6) == NULL) + return (0); - /* - * check if IPv4 src matches the IPv4 address derived from the - * local 6to4 address masked by prefixmask. - * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 - * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 - */ - bzero(&a, sizeof(a)); - bcopy(GET_V4(&addr6), &a, sizeof(a)); - bcopy(GET_V4(&mask6), &mask, sizeof(mask)); - a.s_addr &= mask.s_addr; - b = ip.ip_src; - b.s_addr &= mask.s_addr; - if (a.s_addr != b.s_addr) + if (sin4addr.sin_addr.s_addr != ip.ip_dst.s_addr) return (0); + if (IN6_IS_ADDR_6TO4(&addr6)) { + /* + * 6to4 (RFC 3056). + * Check if IPv4 src matches the IPv4 address derived + * from the local 6to4 address masked by prefixmask. + * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 + * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 + */ + memcpy(&sin4mask.sin_addr, GET_V4(&mask6), + sizeof(sin4mask.sin_addr)); + if ((sin4addr.sin_addr.s_addr & sin4mask.sin_addr.s_addr) != + (ip.ip_src.s_addr & sin4mask.sin_addr.s_addr)) + return (0); + } else { + /* 6rd (RFC 5569) */ + /* + * No restriction on the src address in the case of + * 6rd because the stf(4) interface always has a + * prefix which covers whole of IPv4 src address + * range. So, stf_output() will catch all of + * 6rd-capsuled IPv4 traffic with suspicious inner dst + * IPv4 address (i.e. the IPv6 destination address is + * one the admin does not like to route to outside), + * and then it discard them silently. + */ + } + /* stf interface makes single side match only */ return (32); } @@ -387,30 +417,38 @@ { struct ifaddr *ia; struct in_ifaddr *ia4; - struct in6_ifaddr *ia6; - struct sockaddr_in6 *sin6; + struct in6_addr addr6, mask6; + struct sockaddr_in sin4; + struct stf_softc *sc; struct in_addr in; NET_EPOCH_ASSERT(); + sc = ifp->if_softc; + CK_STAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) { if (ia->ifa_addr->sa_family != AF_INET6) continue; - sin6 = (struct sockaddr_in6 *)ia->ifa_addr; - if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) - continue; - bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); + addr6 = *IFA_IN6(ia); + mask6 = *IFA_MASKIN6(ia); + if (sc->srcv4_addr != INADDR_ANY) + bcopy(&sc->srcv4_addr, &in, sizeof(in)); + else { + if (stf_getin4addr(sc, &sin4, addr6, mask6) == NULL) + continue; + bcopy(&sin4.sin_addr, &in, sizeof(in)); + } + CK_LIST_FOREACH(ia4, INADDR_HASH(in.s_addr), ia_hash) if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) break; if (ia4 == NULL) continue; - ia6 = (struct in6_ifaddr *)ia; + *addr = addr6; + *mask = mask6; - *addr = sin6->sin6_addr; - *mask = ia6->ia_prefixmask.sin6_addr; return (0); } @@ -423,8 +461,7 @@ { struct stf_softc *sc; const struct sockaddr_in6 *dst6; - struct in_addr in4; - const void *ptr; + struct sockaddr_in dst4, src4; u_int8_t tos; struct ip *ip; struct ip6_hdr *ip6; @@ -474,17 +511,17 @@ * Pickup the right outer dst addr from the list of candidates. * ip6_dst has priority as it may be able to give us shorter IPv4 hops. */ - ptr = NULL; - if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) - ptr = GET_V4(&ip6->ip6_dst); - else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) - ptr = GET_V4(&dst6->sin6_addr); - else { - m_freem(m); - if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); - return (ENETUNREACH); + if (stf_getin4addr_in6(sc, &dst4, addr6, mask6, + ip6->ip6_dst) == NULL) { + if (sc->braddr != INADDR_ANY) + dst4.sin_addr.s_addr = sc->braddr; + else if (stf_getin4addr_in6(sc, &dst4, addr6, mask6, + dst6->sin6_addr) == NULL) { + m_freem(m); + if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); + return (ENETUNREACH); + } } - bcopy(ptr, &in4, sizeof(in4)); if (bpf_peers_present(ifp->if_bpf)) { /* @@ -507,8 +544,16 @@ bzero(ip, sizeof(*ip)); - bcopy(GET_V4(&addr6), &ip->ip_src, sizeof(ip->ip_src)); - bcopy(&in4, &ip->ip_dst, sizeof(ip->ip_dst)); + if (sc->srcv4_addr != INADDR_ANY) + src4.sin_addr.s_addr = sc->srcv4_addr; + else if (stf_getin4addr(sc, &src4, addr6, mask6) == NULL) { + m_freem(m); + if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); + return (ENETUNREACH); + } + bcopy(&src4.sin_addr, &ip->ip_src, sizeof(ip->ip_src)); + bcopy(&dst4.sin_addr, &ip->ip_dst, sizeof(ip->ip_dst)); + ip->ip_p = IPPROTO_IPV6; ip->ip_ttl = ip_stf_ttl; ip->ip_len = htons(m->m_pkthdr.len); @@ -556,13 +601,6 @@ return (-1); } - /* - * reject packets with private address range. - * (requirement from RFC3056 section 2 1st paragraph) - */ - if (isrfc1918addr(in)) - return (-1); - /* * reject packets with broadcast */ @@ -624,6 +662,7 @@ struct ip6_hdr *ip6; u_int8_t otos, itos; struct ifnet *ifp; + struct nhop_object *nh; NET_EPOCH_ASSERT(); @@ -674,6 +713,32 @@ return (IPPROTO_DONE); } + /* + * reject packets with private address range. + * (requirement from RFC3056 section 2 1st paragraph) + */ + if ((IN6_IS_ADDR_6TO4(&ip6->ip6_src) && isrfc1918addr(&ip->ip_src)) || + (IN6_IS_ADDR_6TO4(&ip6->ip6_dst) && isrfc1918addr(&ip->ip_dst))) { + m_freem(m); + return (IPPROTO_DONE); + } + + /* + * Ignore if the destination is the same stf interface because + * all of valid IPv6 outgoing traffic should go interfaces + * except for it. + */ + nh = fib6_lookup(sc->sc_fibnum, &ip6->ip6_dst, 0, 0, 0); + if (nh == NULL) { + m_free(m); + return (IPPROTO_DONE); + } + if ((nh->nh_ifp == ifp) && + (!IN6_ARE_ADDR_EQUAL(&ip6->ip6_src, &nh->gw6_sa.sin6_addr))) { + m_free(m); + return (IPPROTO_DONE); + } + itos = IPV6_TRAFFIC_CLASS(ip6); if ((ifp->if_flags & IFF_LINK1) != 0) ip_ecn_egress(ECN_ALLOWED, &otos, &itos); @@ -709,34 +774,159 @@ return (IPPROTO_DONE); } +static struct sockaddr_in * +stf_getin4addr_in6(struct stf_softc *sc, struct sockaddr_in *sin, + struct in6_addr addr6, struct in6_addr mask6, struct in6_addr in6) +{ + int i; + + /* + * When (src addr & src mask) != (in6 & src mask), + * the dst is not in the 6rd domain. The IPv4 address must + * not be used. + */ + for (i = 0; i < sizeof(addr6); i++) { + if ((((u_char *)&addr6)[i] & ((u_char *)&mask6)[i]) != + (((u_char *)&in6)[i] & ((u_char *)&mask6)[i])) + return (NULL); + } + + /* After the mask check, use in6 instead of addr6. */ + return (stf_getin4addr(sc, sin, in6, mask6)); +} + +static struct sockaddr_in * +stf_getin4addr(struct stf_softc *sc, struct sockaddr_in *sin, + struct in6_addr addr6, struct in6_addr mask6) +{ + struct in_addr *in; + + memset(sin, 0, sizeof(*sin)); + in = &sin->sin_addr; + if (IN6_IS_ADDR_6TO4(&addr6)) { + /* 6to4 (RFC 3056) */ + bcopy(GET_V4(&addr6), in, sizeof(*in)); + if (isrfc1918addr(in)) + return (NULL); + } else { + /* 6rd (RFC 5569) */ + in_addr_t v4prefix; + uint8_t *v6 = (uint8_t*)&addr6; + uint64_t v6prefix; + u_int plen; + u_int v4suffixlen; + + v4prefix = 0; + if (sc->v4prefixlen < 32) { + v4suffixlen = 32 - sc->v4prefixlen; + v4prefix = ntohl(sc->srcv4_addr) & + (0xffffffffU << v4suffixlen); + } else { + MPASS(sc->v4prefixlen == 32); + v4suffixlen = 32; + } + + plen = in6_mask2len(&mask6, NULL); + if (plen > 64) + return (NULL); + + /* To make this simple we do not support prefixes longer than + * 64 bits. RFC5969 says "a 6rd delegated prefix SHOULD be /64 + * or shorter." so this is a moderately safe assumption. */ + v6prefix = be64toh(*(uint64_t *)v6); + + /* Shift away the v6 prefix itself. */ + v6prefix <<= plen; + v6prefix >>= plen; + + /* Now shift away everything after the v4 address. */ + v6prefix >>= 64 - plen - v4suffixlen; + + sin->sin_addr.s_addr = htonl(v4prefix | (uint32_t)v6prefix); + } + + return (sin); +} + static int stf_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) { struct ifaddr *ifa; + struct ifdrv *ifd; struct ifreq *ifr; - struct sockaddr_in6 *sin6; - struct in_addr addr; + struct sockaddr_in sin4; + struct stf_softc *sc_cur; + struct stfv4args args; int error, mtu; error = 0; + sc_cur = ifp->if_softc; + switch (cmd) { + case SIOCSDRVSPEC: + ifd = (struct ifdrv *)data; + error = priv_check(curthread, PRIV_NET_ADDIFADDR); + if (error) + break; + if (ifd->ifd_cmd == STF6RD_SV4NET) { + if (ifd->ifd_len != sizeof(args)) { + error = EINVAL; + break; + } + bzero(&args, sizeof(args)); + error = copyin(ifd->ifd_data, &args, ifd->ifd_len); + if (error) + break; + + if (args.v4_prefixlen < 1 || args.v4_prefixlen > 32) { + error = EINVAL; + break; + } + + bcopy(&args.srcv4_addr, &sc_cur->srcv4_addr, + sizeof(sc_cur->srcv4_addr)); + sc_cur->v4prefixlen = args.v4_prefixlen; + } else if (ifd->ifd_cmd == STF6RD_SBR) { + if (ifd->ifd_len != sizeof(args)) { + error = EINVAL; + break; + } + bzero(&args, sizeof(args)); + error = copyin(ifd->ifd_data, &args, ifd->ifd_len); + if (error) + break; + sc_cur->braddr = args.braddr.s_addr; + } else + error = EINVAL; + break; + case SIOCGDRVSPEC: + ifd = (struct ifdrv *)data; + if (ifd->ifd_cmd != STF6RD_GV4NET) { + error = EINVAL; + break; + } + if (ifd->ifd_len != sizeof(args)) { + error = EINVAL; + break; + } + bzero(&args, sizeof(args)); + args.srcv4_addr.s_addr = sc_cur->srcv4_addr; + args.braddr.s_addr = sc_cur->braddr; + args.v4_prefixlen = sc_cur->v4prefixlen; + error = copyout(&args, ifd->ifd_data, ifd->ifd_len); + break; case SIOCSIFADDR: ifa = (struct ifaddr *)data; if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { error = EAFNOSUPPORT; break; } - sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; - if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { + if (stf_getin4addr(sc_cur, &sin4, + satosin6(ifa->ifa_addr)->sin6_addr, + satosin6(ifa->ifa_netmask)->sin6_addr) == NULL) { error = EINVAL; break; } - bcopy(GET_V4(&sin6->sin6_addr), &addr, sizeof(addr)); - if (isrfc1918addr(&addr)) { - error = EINVAL; - break; - } - ifp->if_flags |= IFF_UP; ifp->if_drv_flags |= IFF_DRV_RUNNING; break; diff --git a/sys/netinet6/in6_var.h b/sys/netinet6/in6_var.h --- a/sys/netinet6/in6_var.h +++ b/sys/netinet6/in6_var.h @@ -407,6 +407,7 @@ #define IA6_DSTSIN6(ia) (&((ia)->ia_dstaddr)) #define IFA_IN6(x) (&((struct sockaddr_in6 *)((x)->ifa_addr))->sin6_addr) #define IFA_DSTIN6(x) (&((struct sockaddr_in6 *)((x)->ifa_dstaddr))->sin6_addr) +#define IFA_MASKIN6(x) (&((struct sockaddr_in6 *)((x)->ifa_netmask))->sin6_addr) #define IFPR_IN6(x) (&((struct sockaddr_in6 *)((x)->ifpr_prefix))->sin6_addr)