nd6_rtr.c

eCos/RedBoot for勤研ARM AnywhereII(4510) 含全部源代码

						      IN6_IFF_NOTREADY|
						      IN6_IFF_ANYCAST);
	if (ifa == NULL) {
		/* XXX: freebsd does not have ifa_ifwithaf */
#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
		for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
#elif defined(__FreeBSD__) && __FreeBSD__ >= 4
		TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
#else
		for (ifa = ifp->if_addrlist.tqh_first;
		     ifa;
		     ifa = ifa->ifa_list.tqe_next)
#endif
		{
			if (ifa->ifa_addr->sa_family == AF_INET6)
				break;
		}
		/* should we care about ia6_flags? */
	}
	if (ifa == NULL) {
		/*
		 * This can still happen, when, for example, we receive an RA
		 * containing a prefix with the L bit set and the A bit clear,
		 * after removing all IPv6 addresses on the receiving
		 * interface.  This should, of course, be rare though.
		 */
		nd6log((LOG_NOTICE,
		    "nd6_prefix_onlink: failed to find any ifaddr"
		    " to add route for a prefix(%s/%d) on %s\n",
		    ip6_sprintf(&pr->ndpr_prefix.sin6_addr),
		    pr->ndpr_plen, if_name(ifp)));
		return(0);
	}

	/*
	 * in6_ifinit() sets nd6_rtrequest to ifa_rtrequest for all ifaddrs.
	 * ifa->ifa_rtrequest = nd6_rtrequest;
	 */
	bzero(&mask6, sizeof(mask6));
	mask6.sin6_len = sizeof(mask6);
	mask6.sin6_addr = pr->ndpr_mask;
	/* rtrequest() will probably set RTF_UP, but we're not sure. */
	rtflags = ifa->ifa_flags | RTF_UP;
	if (nd6_need_cache(ifp)) {
		/* explicitly set in case ifa_flags does not set the flag. */
		rtflags |= RTF_CLONING;
	} else {
		/*
		 * explicitly clear the cloning bit in case ifa_flags sets it.
		 */
		rtflags &= ~RTF_CLONING;
	}
	error = rtrequest(RTM_ADD, (struct sockaddr *)&pr->ndpr_prefix,
			  ifa->ifa_addr, (struct sockaddr *)&mask6,
			  rtflags, &rt);
	if (error == 0) {
		if (rt != NULL) /* this should be non NULL, though */
			nd6_rtmsg(RTM_ADD, rt);
		pr->ndpr_stateflags |= NDPRF_ONLINK;
	}
	else {
		nd6log((LOG_ERR, "nd6_prefix_onlink: failed to add route for a"
		    " prefix (%s/%d) on %s, gw=%s, mask=%s, flags=%lx "
		    "errno = %d\n",
		    ip6_sprintf(&pr->ndpr_prefix.sin6_addr),
		    pr->ndpr_plen, if_name(ifp),
		    ip6_sprintf(&((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr),
		    ip6_sprintf(&mask6.sin6_addr), rtflags, error));
	}

	if (rt != NULL)
		rt->rt_refcnt--;

	return(error);
}

int
nd6_prefix_offlink(pr)
	struct nd_prefix *pr;
{
	int error = 0;
	struct ifnet *ifp = pr->ndpr_ifp;
	struct nd_prefix *opr;
	struct sockaddr_in6 sa6, mask6;
	struct rtentry *rt = NULL;

	/* sanity check */
	if ((pr->ndpr_stateflags & NDPRF_ONLINK) == 0) {
		nd6log((LOG_ERR,
		    "nd6_prefix_offlink: %s/%d is already off-link\n",
		    ip6_sprintf(&pr->ndpr_prefix.sin6_addr), pr->ndpr_plen));
		return(EEXIST);
	}

	bzero(&sa6, sizeof(sa6));
	sa6.sin6_family = AF_INET6;
	sa6.sin6_len = sizeof(sa6);
	bcopy(&pr->ndpr_prefix.sin6_addr, &sa6.sin6_addr,
	      sizeof(struct in6_addr));
	bzero(&mask6, sizeof(mask6));
	mask6.sin6_family = AF_INET6;
	mask6.sin6_len = sizeof(sa6);
	bcopy(&pr->ndpr_mask, &mask6.sin6_addr, sizeof(struct in6_addr));
	error = rtrequest(RTM_DELETE, (struct sockaddr *)&sa6, NULL,
			  (struct sockaddr *)&mask6, 0, &rt);
	if (error == 0) {
		pr->ndpr_stateflags &= ~NDPRF_ONLINK;

		/* report the route deletion to the routing socket. */
		if (rt != NULL)
			nd6_rtmsg(RTM_DELETE, rt);

		/*
		 * There might be the same prefix on another interface,
		 * the prefix which could not be on-link just because we have
		 * the interface route (see comments in nd6_prefix_onlink).
		 * If there's one, try to make the prefix on-link on the
		 * interface.
		 */
		for (opr = nd_prefix.lh_first; opr; opr = opr->ndpr_next) {
			if (opr == pr)
				continue;

			if ((opr->ndpr_stateflags & NDPRF_ONLINK) != 0)
				continue;

			/*
			 * KAME specific: detached prefixes should not be
			 * on-link.
			 */
			if ((opr->ndpr_stateflags & NDPRF_DETACHED) != 0)
				continue;

			if (opr->ndpr_plen == pr->ndpr_plen &&
			    in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr,
						 &opr->ndpr_prefix.sin6_addr,
						 pr->ndpr_plen)) {
				int e;

				if ((e = nd6_prefix_onlink(opr)) != 0) {
					nd6log((LOG_ERR,
					    "nd6_prefix_offlink: failed to "
					    "recover a prefix %s/%d from %s "
					    "to %s (errno = %d)\n",
					    ip6_sprintf(&opr->ndpr_prefix.sin6_addr),
					    opr->ndpr_plen, if_name(ifp),
					    if_name(opr->ndpr_ifp), e));
				}
			}
		}
	}
	else {
		/* XXX: can we still set the NDPRF_ONLINK flag? */
		nd6log((LOG_ERR,
		    "nd6_prefix_offlink: failed to delete route: "
		    "%s/%d on %s (errno = %d)\n",
		    ip6_sprintf(&sa6.sin6_addr), pr->ndpr_plen, if_name(ifp),
		    error));
	}

	if (rt != NULL) {
		if (rt->rt_refcnt <= 0) {
			/* XXX: we should free the entry ourselves. */
			rt->rt_refcnt++;
			rtfree(rt);
		}
	}

	return(error);
}

static struct in6_ifaddr *
in6_ifadd(pr)
	struct nd_prefix *pr;
{
	struct ifnet *ifp = pr->ndpr_ifp;
	struct ifaddr *ifa;
	struct in6_aliasreq ifra;
	struct in6_ifaddr *ia, *ib;
	int error, plen0;
	struct in6_addr mask;
	int prefixlen = pr->ndpr_plen;

	in6_prefixlen2mask(&mask, prefixlen);

	/*
	 * find a link-local address (will be interface ID).
	 * Is it really mandatory? Theoretically, a global or a site-local
	 * address can be configured without a link-local address, if we
	 * have a unique interface identifier...
	 *
	 * it is not mandatory to have a link-local address, we can generate
	 * interface identifier on the fly.  we do this because:
	 * (1) it should be the easiest way to find interface identifier.
	 * (2) RFC2462 5.4 suggesting the use of the same interface identifier
	 * for multiple addresses on a single interface, and possible shortcut
	 * of DAD.  we omitted DAD for this reason in the past.
	 * (3) a user can prevent autoconfiguration of global address 
	 * by removing link-local address by hand (this is partly because we
	 * don't have other way to control the use of IPv6 on a interface.
	 * this has been our design choice - cf. NRL's "ifconfig auto").
	 * (4) it is easier to manage when an interface has addresses
	 * with the same interface identifier, than to have multiple addresses
	 * with different interface identifiers.
	 */
	ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 0); /* 0 is OK? */
	if (ifa)
		ib = (struct in6_ifaddr *)ifa;
	else
		return NULL;

#if 0 /* don't care link local addr state, and always do DAD */
	/* if link-local address is not eligible, do not autoconfigure. */
	if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_NOTREADY) {
		printf("in6_ifadd: link-local address not ready\n");
		return NULL;
	}
#endif

	/* prefixlen + ifidlen must be equal to 128 */
	plen0 = in6_mask2len(&ib->ia_prefixmask.sin6_addr, NULL);
	if (prefixlen != plen0) {
		nd6log((LOG_INFO, "in6_ifadd: wrong prefixlen for %s "
		    "(prefix=%d ifid=%d)\n",
		    if_name(ifp), prefixlen, 128 - plen0));
		return NULL;
	}

	/* make ifaddr */

	bzero(&ifra, sizeof(ifra));
	/*
	 * in6_update_ifa() does not use ifra_name, but we accurately set it
	 * for safety.
	 */
	strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
	ifra.ifra_addr.sin6_family = AF_INET6;
	ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6);
	/* prefix */
	bcopy(&pr->ndpr_prefix.sin6_addr, &ifra.ifra_addr.sin6_addr,
	      sizeof(ifra.ifra_addr.sin6_addr));
	ifra.ifra_addr.sin6_addr.s6_addr32[0] &= mask.s6_addr32[0];
	ifra.ifra_addr.sin6_addr.s6_addr32[1] &= mask.s6_addr32[1];
	ifra.ifra_addr.sin6_addr.s6_addr32[2] &= mask.s6_addr32[2];
	ifra.ifra_addr.sin6_addr.s6_addr32[3] &= mask.s6_addr32[3];

	/* interface ID */
	ifra.ifra_addr.sin6_addr.s6_addr32[0] |=
	    (ib->ia_addr.sin6_addr.s6_addr32[0] & ~mask.s6_addr32[0]);
	ifra.ifra_addr.sin6_addr.s6_addr32[1] |=
	    (ib->ia_addr.sin6_addr.s6_addr32[1] & ~mask.s6_addr32[1]);
	ifra.ifra_addr.sin6_addr.s6_addr32[2] |=
	    (ib->ia_addr.sin6_addr.s6_addr32[2] & ~mask.s6_addr32[2]);
	ifra.ifra_addr.sin6_addr.s6_addr32[3] |=
	    (ib->ia_addr.sin6_addr.s6_addr32[3] & ~mask.s6_addr32[3]);
	    
	/* new prefix mask. */
	ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
	ifra.ifra_prefixmask.sin6_family = AF_INET6;
	bcopy(&mask, &ifra.ifra_prefixmask.sin6_addr,
	      sizeof(ifra.ifra_prefixmask.sin6_addr));

	/*
	 * lifetime.
	 * XXX: in6_init_address_ltimes would override these values later.
	 * We should reconsider this logic. 
	 */
	ifra.ifra_lifetime.ia6t_vltime = pr->ndpr_vltime;
	ifra.ifra_lifetime.ia6t_pltime = pr->ndpr_pltime;

	/* XXX: scope zone ID? */

	ifra.ifra_flags |= IN6_IFF_AUTOCONF; /* obey autoconf */

	/* allocate ifaddr structure, link into chain, etc. */
	if ((error = in6_update_ifa(ifp, &ifra, NULL)) != 0) {
		nd6log((LOG_ERR,
		    "in6_ifadd: failed to make ifaddr %s on %s (errno=%d)\n",
		    ip6_sprintf(&ifra.ifra_addr.sin6_addr), if_name(ifp),
		    error));
		return(NULL);	/* ifaddr must not have been allocated. */
	}

	ia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr);

	return(ia);		/* this is always non-NULL */
}

int
in6_tmpifadd(ia0, forcegen)
	const struct in6_ifaddr *ia0; /* corresponding public address */
	int forcegen;
{
	struct ifnet *ifp = ia0->ia_ifa.ifa_ifp;
	struct in6_ifaddr *newia, *ia;
	struct in6_aliasreq ifra;
	int i, error;
	int trylimit = 3;	/* XXX: adhoc value */
	u_int32_t randid[2];
	u_int32_t vltime0, pltime0;
#if !(defined(__FreeBSD__) && __FreeBSD__ >= 3)
	time_t time_second = (time_t)time.tv_sec;
#endif

	bzero(&ifra, sizeof(ifra));
	strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
	ifra.ifra_addr = ia0->ia_addr;
	/* copy prefix mask */
	ifra.ifra_prefixmask = ia0->ia_prefixmask;
	/* clear the old IFID */
	for (i = 0; i < 4; i++) {
		ifra.ifra_addr.sin6_addr.s6_addr32[i]
			&= ifra.ifra_prefixmask.sin6_addr.s6_addr32[i];
	}

  again:
	if (in6_get_tmpifid(ifp, (u_int8_t *)randid,
			    (const u_int8_t *)&ia0->ia_addr.sin6_addr.s6_addr[8],
			    forcegen)) {
		nd6log((LOG_NOTICE, "in6_tmpifadd: failed to find a good "
			"random IFID\n"));
		return(EINVAL);
	}
	ifra.ifra_addr.sin6_addr.s6_addr32[2]
		|= (randid[0] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[2]));
	ifra.ifra_addr.sin6_addr.s6_addr32[3]
		|= (randid[1] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[3]));

	/*
	 * in6_get_tmpifid() quite likely provided a unique interface ID.
	 * However, we may still have a chance to see collision, because
	 * there may be a time lag between generation of the ID and generation
	 * of the address.  So, we'll do one more sanity check.
	 */
	for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
		if (SA6_ARE_ADDR_EQUAL(&ia->ia_addr,
				       &ifra.ifra_addr)) {
			if (trylimit-- == 0) {
				/*
				 * Give up.  Something strange should have
				 * happened.
				 */
				nd6log((LOG_NOTICE, "in6_tmpifadd: failed to "
					"find a unique random IFID\n"));
				return(EEXIST);
			}
			forcegen = 1;
			goto again;
		}
	}

	/*
	 * The Valid Lifetime is the lower of the Valid Lifetime of the
         * public address or TEMP_VALID_LIFETIME.
	 * The Preferred Lifetime is the lower of the Preferred Lifetime
         * of the public address or TEMP_PREFERRED_LIFETIME -
         * DESYNC_FACTOR.
	 */
	if (ia0->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
		vltime0 = IFA6_IS_INVALID(ia0) ? 0 :
			(ia0->ia6_lifetime.ia6t_vltime -
			 (time_second - ia0->ia6_updatetime));
		if (vltime0 > ip6_temp_valid_lifetime)
			vltime0 = ip6_temp_valid_lifetime;
	} else
		vltime0 = ip6_temp_valid_lifetime;
	if (ia0->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
		pltime0 = IFA6_IS_DEPRECATED(ia0) ? 0 :
			(ia0->ia6_lifetime.ia6t_pltime -
			 (time_second - ia0->ia6_updatetime));
		if (pltime0 > ip6_temp_preferred_lifetime - ip6_desync_factor){
			pltime0 = ip6_temp_preferred_lifetime -
				ip6_desync_factor;
		}
	} else
		pltime0 = ip6_temp_preferred_lifetime - ip6_desync_factor;
	ifra.ifra_lifetime.ia6t_vltime = vltime0;
	ifra.ifra_lifetime.ia6t_pltime = pltime0;

	/*
	 * A temporary address is created only if this calculated Preferred
	 * Lifetime is greater than REGEN_ADVANCE time units.
	 */
	if (ifra.ifra_lifetime.ia6t_pltime <= ip6_temp_regen_advance)
		return(0);

	/* XXX: scope zone ID? */

	ifra.ifra_flags |= (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY);

	/* allocate ifaddr structure, link into chain, etc. */
	if ((error = in6_update_ifa(ifp, &ifra, NULL)) != 0)
		return(error);

	newia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr);
	if (newia == NULL) {	/* XXX: can it happen? */
		nd6log((LOG_ERR,
		    "in6_tmpifadd: ifa update succeeded, but we got "
		    "no ifaddr\n"));
		return(EINVAL); /* XXX */
	}
	newia->ia6_ndpr = ia0->ia6_ndpr;
	newia->ia6_ndpr->ndpr_refcnt++;

	/*
	 * A newly added address might affect the status of other addresses.
	 * XXX: when the temporary address is generated with a new public
	 * address, the onlink check is redundant.  However, it would be safe
	 * to do the check explicitly everywhere a new address is generated,
	 * and, in fact, we surely need the check when we create a new
	 * temporary address due to deprecation of an old temporary address.
	 */
	pfxlist_onlink_check();

	return(0);
}	    

int
in6_init_prefix_ltimes(struct nd_prefix *ndpr)
{
#if !(defined(__FreeBSD__) && __FreeBSD__ >= 3)
	long time_second = time.tv_sec;
#endif

	/* check if preferred lifetime > valid lifetime.  RFC2462 5.5.3 (c) */
	if (ndpr->ndpr_pltime > ndpr->ndpr_vltime) {
		nd6log((LOG_INFO, "in6_init_prefix_ltimes: preferred lifetime"
		    "(%d) is greater than valid lifetime(%d)\n",
		    (u_int)ndpr->ndpr_pltime, (u_int)ndpr->ndpr_vltime));
		return (EINVAL);
	}
	if (ndpr->ndpr_pltime == ND6_INFINITE_LIFETIME)
		ndpr->ndpr_preferred = 0;
	else
		ndpr->ndpr_preferred = time_second + ndpr->ndpr_pltime;
	if (ndpr->ndpr_vltime == ND6_INFINITE_LIFETIME)
		ndpr->ndpr_expire = 0;
	else
		ndpr->ndpr_expire = time_second + ndpr->ndpr_vltime;

	return 0;
}

static void
in6_init_address_ltimes(struct nd_prefix *new, struct in6_addrlifetime *lt6)
{
#if !(defined(__FreeBSD__) && __FreeBSD__ >= 3)
	long time_second = time.tv_sec;
#endif

	/* Valid lifetime must not be updated unless explicitly specified. */
	/* init ia6t