nd6.c

eCos操作系统源码

			}
		}
		break;

	case RTM_DELETE:
		if (!ln)
			break;
		/* leave from solicited node multicast for proxy ND */
		if ((rt->rt_flags & RTF_ANNOUNCE) != 0 &&
		    (ifp->if_flags & IFF_MULTICAST) != 0) {
			struct in6_addr llsol;
			struct in6_multi *in6m;

			llsol = SIN6(rt_key(rt))->sin6_addr;
			llsol.s6_addr16[0] = htons(0xff02);
			llsol.s6_addr16[1] = htons(ifp->if_index);
			llsol.s6_addr32[1] = 0;
			llsol.s6_addr32[2] = htonl(1);
			llsol.s6_addr8[12] = 0xff;

			IN6_LOOKUP_MULTI(llsol, ifp, in6m);
			if (in6m)
				in6_delmulti(in6m);
		}
		nd6_inuse--;
		ln->ln_next->ln_prev = ln->ln_prev;
		ln->ln_prev->ln_next = ln->ln_next;
		ln->ln_prev = NULL;
		rt->rt_llinfo = 0;
		rt->rt_flags &= ~RTF_LLINFO;
		if (ln->ln_hold)
			m_freem(ln->ln_hold);
		Free((caddr_t)ln);
	}
}

int
nd6_ioctl(cmd, data, ifp)
	u_long cmd;
	caddr_t	data;
	struct ifnet *ifp;
{
	struct in6_drlist *drl = (struct in6_drlist *)data;
	struct in6_oprlist *oprl = (struct in6_oprlist *)data;
	struct in6_ndireq *ndi = (struct in6_ndireq *)data;
	struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data;
	struct in6_ndifreq *ndif = (struct in6_ndifreq *)data;
	struct nd_defrouter *dr;
	struct nd_prefix *pr;
	struct rtentry *rt;
	int i = 0, error = 0;
	int s;

	switch (cmd) {
	case SIOCGDRLST_IN6:
		/*
		 * obsolete API, use sysctl under net.inet6.icmp6
		 */
		bzero(drl, sizeof(*drl));
#ifdef __NetBSD__
		s = splsoftnet();
#else
		s = splnet();
#endif
		dr = TAILQ_FIRST(&nd_defrouter);
		while (dr && i < DRLSTSIZ) {
			drl->defrouter[i].rtaddr = dr->rtaddr;
			if (IN6_IS_ADDR_LINKLOCAL(&drl->defrouter[i].rtaddr)) {
				/* XXX: need to this hack for KAME stack */
				drl->defrouter[i].rtaddr.s6_addr16[1] = 0;
			} else
				log(LOG_ERR,
				    "default router list contains a "
				    "non-linklocal address(%s)\n",
				    ip6_sprintf(&drl->defrouter[i].rtaddr));

			drl->defrouter[i].flags = dr->flags;
			drl->defrouter[i].rtlifetime = dr->rtlifetime;
			drl->defrouter[i].expire = dr->expire;
			drl->defrouter[i].if_index = dr->ifp->if_index;
			i++;
			dr = TAILQ_NEXT(dr, dr_entry);
		}
		splx(s);
		break;
	case SIOCGPRLST_IN6:
		/*
		 * obsolete API, use sysctl under net.inet6.icmp6
		 *
		 * XXX the structure in6_prlist was changed in backward-
		 * incompatible manner.  in6_oprlist is used for SIOCGPRLST_IN6,
		 * in6_prlist is used for nd6_sysctl() - fill_prlist().
		 */
		/*
		 * XXX meaning of fields, especialy "raflags", is very
		 * differnet between RA prefix list and RR/static prefix list.
		 * how about separating ioctls into two?
		 */
		bzero(oprl, sizeof(*oprl));
#ifdef __NetBSD__
		s = splsoftnet();
#else
		s = splnet();
#endif
		pr = nd_prefix.lh_first;
		while (pr && i < PRLSTSIZ) {
			struct nd_pfxrouter *pfr;
			int j;

			(void)in6_embedscope(&oprl->prefix[i].prefix,
					     &pr->ndpr_prefix);
			oprl->prefix[i].raflags = pr->ndpr_raf;
			oprl->prefix[i].prefixlen = pr->ndpr_plen;
			oprl->prefix[i].vltime = pr->ndpr_vltime;
			oprl->prefix[i].pltime = pr->ndpr_pltime;
			oprl->prefix[i].if_index = pr->ndpr_ifp->if_index;
			if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME)
				oprl->prefix[i].expire = 0;
			else {
				time_t maxexpire;

				/* XXX: we assume time_t is signed. */
				maxexpire = (-1) &
					~(1 << ((sizeof(maxexpire) * 8) - 1));
				if (pr->ndpr_vltime <
				    maxexpire - pr->ndpr_lastupdate) {
					oprl->prefix[i].expire =
						 pr->ndpr_lastupdate +
						pr->ndpr_vltime;
				} else
					oprl->prefix[i].expire = maxexpire;
			}
			pfr = pr->ndpr_advrtrs.lh_first;
			j = 0;
			while (pfr) {
				if (j < DRLSTSIZ) {
#define RTRADDR oprl->prefix[i].advrtr[j]
					RTRADDR = pfr->router->rtaddr;
					if (IN6_IS_ADDR_LINKLOCAL(&RTRADDR)) {
						/* XXX: hack for KAME */
						RTRADDR.s6_addr16[1] = 0;
					} else
						log(LOG_ERR,
						    "a router(%s) advertises "
						    "a prefix with "
						    "non-link local address\n",
						    ip6_sprintf(&RTRADDR));
#undef RTRADDR
				}
				j++;
				pfr = pfr->pfr_next;
			}
			oprl->prefix[i].advrtrs = j;
			oprl->prefix[i].origin = PR_ORIG_RA;

			i++;
			pr = pr->ndpr_next;
		}
		splx(s);

		break;
	case OSIOCGIFINFO_IN6:
		if (!nd_ifinfo || i >= nd_ifinfo_indexlim) {
			error = EINVAL;
			break;
		}
		ndi->ndi.linkmtu = nd_ifinfo[ifp->if_index].linkmtu;
		ndi->ndi.maxmtu = nd_ifinfo[ifp->if_index].maxmtu;
		ndi->ndi.basereachable =
		    nd_ifinfo[ifp->if_index].basereachable;
		ndi->ndi.reachable = nd_ifinfo[ifp->if_index].reachable;
		ndi->ndi.retrans = nd_ifinfo[ifp->if_index].retrans;
		ndi->ndi.flags = nd_ifinfo[ifp->if_index].flags;
		ndi->ndi.recalctm = nd_ifinfo[ifp->if_index].recalctm;
		ndi->ndi.chlim = nd_ifinfo[ifp->if_index].chlim;
		ndi->ndi.receivedra = nd_ifinfo[ifp->if_index].receivedra;
		break;
	case SIOCGIFINFO_IN6:
		if (!nd_ifinfo || i >= nd_ifinfo_indexlim) {
			error = EINVAL;
			break;
		}
		ndi->ndi = nd_ifinfo[ifp->if_index];
		break;
	case SIOCSIFINFO_FLAGS:
		/* XXX: almost all other fields of ndi->ndi is unused */
		if (!nd_ifinfo || i >= nd_ifinfo_indexlim) {
			error = EINVAL;
			break;
		}
		nd_ifinfo[ifp->if_index].flags = ndi->ndi.flags;
		break;
	case SIOCSNDFLUSH_IN6:	/* XXX: the ioctl name is confusing... */
		/* sync kernel routing table with the default router list */
		defrouter_reset();
		defrouter_select();
		break;
	case SIOCSPFXFLUSH_IN6:
	    {
		/* flush all the prefix advertised by routers */
		struct nd_prefix *pr, *next;

#ifdef __NetBSD__
		s = splsoftnet();
#else
		s = splnet();
#endif
		for (pr = nd_prefix.lh_first; pr; pr = next) {
			struct in6_ifaddr *ia, *ia_next;

			next = pr->ndpr_next;

			if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr))
				continue; /* XXX */

			/* do we really have to remove addresses as well? */
			for (ia = in6_ifaddr; ia; ia = ia_next) {
				/* ia might be removed.  keep the next ptr. */
				ia_next = ia->ia_next;

				if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0)
					continue;

				if (ia->ia6_ndpr == pr)
					in6_purgeaddr(&ia->ia_ifa);
			}
			prelist_remove(pr);
		}
		splx(s);
		break;
	    }
	case SIOCSRTRFLUSH_IN6:
	    {
		/* flush all the default routers */
		struct nd_defrouter *dr, *next;

#ifdef __NetBSD__
		s = splsoftnet();
#else
		s = splnet();
#endif
		defrouter_reset();
		for (dr = TAILQ_FIRST(&nd_defrouter); dr; dr = next) {
			next = TAILQ_NEXT(dr, dr_entry);
			defrtrlist_del(dr);
		}
		defrouter_select();
		splx(s);
		break;
	    }
	case SIOCGNBRINFO_IN6:
	    {
		struct llinfo_nd6 *ln;
		struct in6_addr nb_addr = nbi->addr; /* make local for safety */

		/*
		 * XXX: KAME specific hack for scoped addresses
		 *      XXXX: for other scopes than link-local?
		 */
		if (IN6_IS_ADDR_LINKLOCAL(&nbi->addr) ||
		    IN6_IS_ADDR_MC_LINKLOCAL(&nbi->addr)) {
			u_int16_t *idp = (u_int16_t *)&nb_addr.s6_addr[2];

			if (*idp == 0)
				*idp = htons(ifp->if_index);
		}

#ifdef __NetBSD__
		s = splsoftnet();
#else
		s = splnet();
#endif
		if ((rt = nd6_lookup(&nb_addr, 0, ifp)) == NULL ||
		    (ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) {
			error = EINVAL;
			splx(s);
			break;
		}
		nbi->state = ln->ln_state;
		nbi->asked = ln->ln_asked;
		nbi->isrouter = ln->ln_router;
		nbi->expire = ln->ln_expire;
		splx(s);
		
		break;
	    }
	case SIOCGDEFIFACE_IN6:	/* XXX: should be implemented as a sysctl? */
		ndif->ifindex = nd6_defifindex;
		break;
	case SIOCSDEFIFACE_IN6:	/* XXX: should be implemented as a sysctl? */
		return(nd6_setdefaultiface(ndif->ifindex));
		break;
	}
	return(error);
}

/*
 * Create neighbor cache entry and cache link-layer address,
 * on reception of inbound ND6 packets.  (RS/RA/NS/redirect)
 */
struct rtentry *
nd6_cache_lladdr(ifp, from, lladdr, lladdrlen, type, code)
	struct ifnet *ifp;
	struct in6_addr *from;
	char *lladdr;
	int lladdrlen;
	int type;	/* ICMP6 type */
	int code;	/* type dependent information */
{
	struct rtentry *rt = NULL;
	struct llinfo_nd6 *ln = NULL;
	int is_newentry;
	struct sockaddr_dl *sdl = NULL;
	int do_update;
	int olladdr;
	int llchange;
	int newstate = 0;
#if !(defined(__FreeBSD__) && __FreeBSD__ >= 3)
	long time_second = time.tv_sec;
#endif

	if (!ifp)
		panic("ifp == NULL in nd6_cache_lladdr");
	if (!from)
		panic("from == NULL in nd6_cache_lladdr");

	/* nothing must be updated for unspecified address */
	if (IN6_IS_ADDR_UNSPECIFIED(from))
		return NULL;

	/*
	 * Validation about ifp->if_addrlen and lladdrlen must be done in
	 * the caller.
	 *
	 * XXX If the link does not have link-layer adderss, what should
	 * we do? (ifp->if_addrlen == 0)
	 * Spec says nothing in sections for RA, RS and NA.  There's small
	 * description on it in NS section (RFC 2461 7.2.3).
	 */

	rt = nd6_lookup(from, 0, ifp);
	if (!rt) {
#if 0
		/* nothing must be done if there's no lladdr */
		if (!lladdr || !lladdrlen)
			return NULL;
#endif

		rt = nd6_lookup(from, 1, ifp);
		is_newentry = 1;
	} else {
		/* do nothing if static ndp is set */
		if (rt->rt_flags & RTF_STATIC)
			return NULL;
		is_newentry = 0;
	}

	if (!rt)
		return NULL;
	if ((rt->rt_flags & (RTF_GATEWAY | RTF_LLINFO)) != RTF_LLINFO) {
fail:
		(void)nd6_free(rt, 0);
		return NULL;
	}
	ln = (struct llinfo_nd6 *)rt->rt_llinfo;
	if (!ln)
		goto fail;
	if (!rt->rt_gateway)
		goto fail;
	if (rt->rt_gateway->sa_family != AF_LINK)
		goto fail;
	sdl = SDL(rt->rt_gateway);

	olladdr = (sdl->sdl_alen) ? 1 : 0;
	if (olladdr && lladdr) {
		if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen))
			llchange = 1;
		else
			llchange = 0;
	} else
		llchange = 0;

	/*
	 * newentry olladdr  lladdr  llchange	(*=record)
	 *	0	n	n	--	(1)
	 *	0	y	n	--	(2)
	 *	0	n	y	--	(3) * STALE
	 *	0	y	y	n	(4) *
	 *	0	y	y	y	(5) * STALE
	 *	1	--	n	--	(6)   NOSTATE(= PASSIVE)
	 *	1	--	y	--	(7) * STALE
	 */

	if (lladdr) {		/* (3-5) and (7) */
		/*
		 * Record source link-layer address
		 * XXX is it dependent to ifp->if_type?
		 */
		sdl->sdl_alen = ifp->if_addrlen;
		bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
	}

	if (!is_newentry) {
		if ((!olladdr && lladdr)		/* (3) */
		 || (olladdr && lladdr && llchange)) {	/* (5) */
			do_update = 1;
			newstate = ND6_LLINFO_STALE;
		} else					/* (1-2,4) */
			do_update = 0;
	} else {
		do_update = 1;
		if (!lladdr)				/* (6) */
			newstate = ND6_LLINFO_NOSTATE;
		else					/* (7) */
			newstate = ND6_LLINFO_STALE;
	}

	if (do_update) {
		/*
		 * Update the state of the neighbor cache.
		 */
		ln->ln_state = newstate;

		if (ln->ln_state == ND6_LLINFO_STALE) {
			/*
			 * XXX: since nd6_output() below will cause
			 * state tansition to DELAY and reset the timer,
			 * we must set the timer now, although it is actually
			 * meaningless.
			 */
			ln->ln_expire = time_second + nd6_gctimer;

			if (ln->ln_hold) {
				/*
				 * we assume ifp is not a p2p here, so just
				 * set the 2nd argument as the 1st one.
				 */
				nd6_output(ifp, ifp, ln->ln_hold,
					   (struct sockaddr_in6 *)rt_key(rt),
					   rt);
				ln->ln_hold = NULL;
			}
		} else if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
			/* probe right away */
			ln->ln_expire = time_second;
		}
	}

	/*
	 * ICMP6 type dependent behavior.
	 *
	 * NS: clear IsRouter if new entry
	 * RS: clear IsRouter
	 * RA: set IsRouter if there's lladdr
	 * redir: clear IsRouter if new entry
	 *
	 * RA case, (1):
	 * The spec says that we must set IsRouter in the following cases:
	 * - If lladdr exist, set IsRouter.  This means (1-5).
	 * - If it is old entry (!newentry), set IsRouter.  This means (7).
	 * So, based on the spec, in (1-5) and (7) cases we must set IsRouter.
	 * A quetion arises for (1) case.  (1) case has no lladdr in the
	 * neighbor cache, this is similar to (6).
	 * This case is rare but we figured that we MUST NOT set IsRouter.
	 *
	 * newentry olladdr  lladdr  llchange	    NS  RS  RA	redir
	 *							D R
	 *	0	n	n	--	(1)	c   ?     s
	 *	0	y	n	--	(2)	c   s     s
	 *	0	n	y	--	(3)	c   s     s
	 *	0	y	y	n	(4)	c   s     s
	 *	0	y	y	y	(5)	c   s     s
	 *	1	--	n	--	(6) c	c 	c s
	 *	1	--	y	--	(7) c	c   s	c s
	 *
	 *					(c=clear s=set)
	 */
	switch (type & 0xff) {
	case ND_NEIGHBOR_SOLICIT:
		/*
		 * New entry must have is_router flag cleared.
		 */
		if (is_newentry)	/* (6-7) */
			ln->ln_router = 0;
		break;
	case ND_REDIRECT:
		/*
		 * If the icmp is a redirect to a better router, always set the
		 * is_router flag.  Otherwise, if the entry is newly created,
		 * clear the flag.  [RFC 2461, sec 8.3]
		 */
		if (code == ND_REDIRECT_ROUTER)
			ln->ln_router = 1;
		else if (is_newentry) /* (6-7) */
			ln->ln_router = 0;
		break;
	case ND_ROUTER_SOLICIT:
		/*
		 * is_router flag must always be cleared.