xref: /illumos-gate/usr/src/uts/common/inet/ip/ip6_input.c (revision 2a93c3751513f2cec775a429a244bec6f0f0a635)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved
24  */
25 /* Copyright (c) 1990 Mentat Inc. */
26 
27 #include <sys/types.h>
28 #include <sys/stream.h>
29 #include <sys/dlpi.h>
30 #include <sys/stropts.h>
31 #include <sys/sysmacros.h>
32 #include <sys/strsubr.h>
33 #include <sys/strlog.h>
34 #include <sys/strsun.h>
35 #include <sys/zone.h>
36 #define	_SUN_TPI_VERSION 2
37 #include <sys/tihdr.h>
38 #include <sys/xti_inet.h>
39 #include <sys/ddi.h>
40 #include <sys/sunddi.h>
41 #include <sys/cmn_err.h>
42 #include <sys/debug.h>
43 #include <sys/kobj.h>
44 #include <sys/modctl.h>
45 #include <sys/atomic.h>
46 #include <sys/policy.h>
47 #include <sys/priv.h>
48 
49 #include <sys/systm.h>
50 #include <sys/param.h>
51 #include <sys/kmem.h>
52 #include <sys/sdt.h>
53 #include <sys/socket.h>
54 #include <sys/vtrace.h>
55 #include <sys/isa_defs.h>
56 #include <sys/mac.h>
57 #include <net/if.h>
58 #include <net/if_arp.h>
59 #include <net/route.h>
60 #include <sys/sockio.h>
61 #include <netinet/in.h>
62 #include <net/if_dl.h>
63 
64 #include <inet/common.h>
65 #include <inet/mi.h>
66 #include <inet/mib2.h>
67 #include <inet/nd.h>
68 #include <inet/arp.h>
69 #include <inet/snmpcom.h>
70 #include <inet/kstatcom.h>
71 
72 #include <netinet/igmp_var.h>
73 #include <netinet/ip6.h>
74 #include <netinet/icmp6.h>
75 #include <netinet/sctp.h>
76 
77 #include <inet/ip.h>
78 #include <inet/ip_impl.h>
79 #include <inet/ip6.h>
80 #include <inet/ip6_asp.h>
81 #include <inet/optcom.h>
82 #include <inet/tcp.h>
83 #include <inet/tcp_impl.h>
84 #include <inet/ip_multi.h>
85 #include <inet/ip_if.h>
86 #include <inet/ip_ire.h>
87 #include <inet/ip_ftable.h>
88 #include <inet/ip_rts.h>
89 #include <inet/ip_ndp.h>
90 #include <inet/ip_listutils.h>
91 #include <netinet/igmp.h>
92 #include <netinet/ip_mroute.h>
93 #include <inet/ipp_common.h>
94 
95 #include <net/pfkeyv2.h>
96 #include <inet/sadb.h>
97 #include <inet/ipsec_impl.h>
98 #include <inet/ipdrop.h>
99 #include <inet/ip_netinfo.h>
100 #include <inet/ilb_ip.h>
101 #include <sys/squeue_impl.h>
102 #include <sys/squeue.h>
103 
104 #include <sys/ethernet.h>
105 #include <net/if_types.h>
106 #include <sys/cpuvar.h>
107 
108 #include <ipp/ipp.h>
109 #include <ipp/ipp_impl.h>
110 #include <ipp/ipgpc/ipgpc.h>
111 
112 #include <sys/pattr.h>
113 #include <inet/ipclassifier.h>
114 #include <inet/sctp_ip.h>
115 #include <inet/sctp/sctp_impl.h>
116 #include <inet/udp_impl.h>
117 #include <sys/sunddi.h>
118 
119 #include <sys/tsol/label.h>
120 #include <sys/tsol/tnet.h>
121 
122 #include <sys/clock_impl.h>	/* For LBOLT_FASTPATH{,64} */
123 
124 #ifdef	DEBUG
125 extern boolean_t skip_sctp_cksum;
126 #endif
127 
128 static void	ip_input_local_v6(ire_t *, mblk_t *, ip6_t *, ip_recv_attr_t *);
129 
130 static void	ip_input_multicast_v6(ire_t *, mblk_t *, ip6_t *,
131     ip_recv_attr_t *);
132 
133 #pragma inline(ip_input_common_v6, ip_input_local_v6, ip_forward_xmit_v6)
134 
135 /*
136  * Direct read side procedure capable of dealing with chains. GLDv3 based
137  * drivers call this function directly with mblk chains while STREAMS
138  * read side procedure ip_rput() calls this for single packet with ip_ring
139  * set to NULL to process one packet at a time.
140  *
141  * The ill will always be valid if this function is called directly from
142  * the driver.
143  *
144  * If ip_input_v6() is called from GLDv3:
145  *
146  *   - This must be a non-VLAN IP stream.
147  *   - 'mp' is either an untagged or a special priority-tagged packet.
148  *   - Any VLAN tag that was in the MAC header has been stripped.
149  *
150  * If the IP header in packet is not 32-bit aligned, every message in the
151  * chain will be aligned before further operations. This is required on SPARC
152  * platform.
153  */
154 void
155 ip_input_v6(ill_t *ill, ill_rx_ring_t *ip_ring, mblk_t *mp_chain,
156     struct mac_header_info_s *mhip)
157 {
158 	(void) ip_input_common_v6(ill, ip_ring, mp_chain, mhip, NULL, NULL,
159 	    NULL);
160 }
161 
162 /*
163  * ip_accept_tcp_v6() - This function is called by the squeue when it retrieves
164  * a chain of packets in the poll mode. The packets have gone through the
165  * data link processing but not IP processing. For performance and latency
166  * reasons, the squeue wants to process the chain in line instead of feeding
167  * it back via ip_input path.
168  *
169  * We set up the ip_recv_attr_t with IRAF_TARGET_SQP to that ip_fanout_v6
170  * will pass back any TCP packets matching the target sqp to
171  * ip_input_common_v6 using ira_target_sqp_mp. Other packets are handled by
172  * ip_input_v6 and ip_fanout_v6 as normal.
173  * The TCP packets that match the target squeue are returned to the caller
174  * as a b_next chain after each packet has been prepend with an mblk
175  * from ip_recv_attr_to_mblk.
176  */
177 mblk_t *
178 ip_accept_tcp_v6(ill_t *ill, ill_rx_ring_t *ip_ring, squeue_t *target_sqp,
179     mblk_t *mp_chain, mblk_t **last, uint_t *cnt)
180 {
181 	return (ip_input_common_v6(ill, ip_ring, mp_chain, NULL, target_sqp,
182 	    last, cnt));
183 }
184 
185 /*
186  * Used by ip_input_v6 and ip_accept_tcp_v6
187  * The last three arguments are only used by ip_accept_tcp_v6, and mhip is
188  * only used by ip_input_v6.
189  */
190 mblk_t *
191 ip_input_common_v6(ill_t *ill, ill_rx_ring_t *ip_ring, mblk_t *mp_chain,
192     struct mac_header_info_s *mhip, squeue_t *target_sqp,
193     mblk_t **last, uint_t *cnt)
194 {
195 	mblk_t		*mp;
196 	ip6_t		*ip6h;
197 	ip_recv_attr_t	iras;	/* Receive attributes */
198 	rtc_t		rtc;
199 	iaflags_t	chain_flags = 0;	/* Fixed for chain */
200 	mblk_t 		*ahead = NULL;	/* Accepted head */
201 	mblk_t		*atail = NULL;	/* Accepted tail */
202 	uint_t		acnt = 0;	/* Accepted count */
203 
204 	ASSERT(mp_chain != NULL);
205 	ASSERT(ill != NULL);
206 
207 	/* These ones do not change as we loop over packets */
208 	iras.ira_ill = iras.ira_rill = ill;
209 	iras.ira_ruifindex = ill->ill_phyint->phyint_ifindex;
210 	iras.ira_rifindex = iras.ira_ruifindex;
211 	iras.ira_sqp = NULL;
212 	iras.ira_ring = ip_ring;
213 	/* For ECMP and outbound transmit ring selection */
214 	iras.ira_xmit_hint = ILL_RING_TO_XMIT_HINT(ip_ring);
215 
216 	iras.ira_target_sqp = target_sqp;
217 	iras.ira_target_sqp_mp = NULL;
218 	if (target_sqp != NULL)
219 		chain_flags |= IRAF_TARGET_SQP;
220 
221 	/*
222 	 * We try to have a mhip pointer when possible, but
223 	 * it might be NULL in some cases. In those cases we
224 	 * have to assume unicast.
225 	 */
226 	iras.ira_mhip = mhip;
227 	iras.ira_flags = 0;
228 	if (mhip != NULL) {
229 		switch (mhip->mhi_dsttype) {
230 		case MAC_ADDRTYPE_MULTICAST :
231 			chain_flags |= IRAF_L2DST_MULTICAST;
232 			break;
233 		case MAC_ADDRTYPE_BROADCAST :
234 			chain_flags |= IRAF_L2DST_BROADCAST;
235 			break;
236 		}
237 	}
238 
239 	/*
240 	 * Initialize the one-element route cache.
241 	 *
242 	 * We do ire caching from one iteration to
243 	 * another. In the event the packet chain contains
244 	 * all packets from the same dst, this caching saves
245 	 * an ire_route_recursive for each of the succeeding
246 	 * packets in a packet chain.
247 	 */
248 	rtc.rtc_ire = NULL;
249 	rtc.rtc_ip6addr = ipv6_all_zeros;
250 
251 	/* Loop over b_next */
252 	for (mp = mp_chain; mp != NULL; mp = mp_chain) {
253 		mp_chain = mp->b_next;
254 		mp->b_next = NULL;
255 
256 		/*
257 		 * if db_ref > 1 then copymsg and free original. Packet
258 		 * may be changed and we do not want the other entity
259 		 * who has a reference to this message to trip over the
260 		 * changes. This is a blind change because trying to
261 		 * catch all places that might change the packet is too
262 		 * difficult.
263 		 *
264 		 * This corresponds to the fast path case, where we have
265 		 * a chain of M_DATA mblks.  We check the db_ref count
266 		 * of only the 1st data block in the mblk chain. There
267 		 * doesn't seem to be a reason why a device driver would
268 		 * send up data with varying db_ref counts in the mblk
269 		 * chain. In any case the Fast path is a private
270 		 * interface, and our drivers don't do such a thing.
271 		 * Given the above assumption, there is no need to walk
272 		 * down the entire mblk chain (which could have a
273 		 * potential performance problem)
274 		 *
275 		 * The "(DB_REF(mp) > 1)" check was moved from ip_rput()
276 		 * to here because of exclusive ip stacks and vnics.
277 		 * Packets transmitted from exclusive stack over vnic
278 		 * can have db_ref > 1 and when it gets looped back to
279 		 * another vnic in a different zone, you have ip_input()
280 		 * getting dblks with db_ref > 1. So if someone
281 		 * complains of TCP performance under this scenario,
282 		 * take a serious look here on the impact of copymsg().
283 		 */
284 		if (DB_REF(mp) > 1) {
285 			if ((mp = ip_fix_dbref(mp, &iras)) == NULL)
286 				continue;
287 		}
288 
289 		/*
290 		 * IP header ptr not aligned?
291 		 * OR IP header not complete in first mblk
292 		 */
293 		ip6h = (ip6_t *)mp->b_rptr;
294 		if (!OK_32PTR(ip6h) || MBLKL(mp) < IPV6_HDR_LEN) {
295 			mp = ip_check_and_align_header(mp, IPV6_HDR_LEN, &iras);
296 			if (mp == NULL)
297 				continue;
298 			ip6h = (ip6_t *)mp->b_rptr;
299 		}
300 
301 		/* Protect against a mix of Ethertypes and IP versions */
302 		if (IPH_HDR_VERSION(ip6h) != IPV6_VERSION) {
303 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsInHdrErrors);
304 			ip_drop_input("ipIfStatsInHdrErrors", mp, ill);
305 			freemsg(mp);
306 			/* mhip might point into 1st packet in the chain. */
307 			iras.ira_mhip = NULL;
308 			continue;
309 		}
310 
311 		/*
312 		 * Check for Martian addrs; we have to explicitly
313 		 * test for for zero dst since this is also used as
314 		 * an indication that the rtc is not used.
315 		 */
316 		if (IN6_IS_ADDR_UNSPECIFIED(&ip6h->ip6_dst)) {
317 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsInAddrErrors);
318 			ip_drop_input("ipIfStatsInAddrErrors", mp, ill);
319 			freemsg(mp);
320 			/* mhip might point into 1st packet in the chain. */
321 			iras.ira_mhip = NULL;
322 			continue;
323 		}
324 		/*
325 		 * Keep L2SRC from a previous packet in chain since mhip
326 		 * might point into an earlier packet in the chain.
327 		 */
328 		chain_flags |= (iras.ira_flags & IRAF_L2SRC_SET);
329 
330 		iras.ira_flags = IRAF_VERIFY_ULP_CKSUM | chain_flags;
331 		iras.ira_free_flags = 0;
332 		iras.ira_cred = NULL;
333 		iras.ira_cpid = NOPID;
334 		iras.ira_tsl = NULL;
335 		iras.ira_zoneid = ALL_ZONES;	/* Default for forwarding */
336 
337 		/*
338 		 * We must count all incoming packets, even if they end
339 		 * up being dropped later on. Defer counting bytes until
340 		 * we have the whole IP header in first mblk.
341 		 */
342 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsHCInReceives);
343 
344 		iras.ira_pktlen = ntohs(ip6h->ip6_plen) + IPV6_HDR_LEN;
345 		UPDATE_MIB(ill->ill_ip_mib, ipIfStatsHCInOctets,
346 		    iras.ira_pktlen);
347 
348 		/*
349 		 * Call one of:
350 		 * 	ill_input_full_v6
351 		 *	ill_input_short_v6
352 		 * The former is used in the case of TX. See ill_set_inputfn().
353 		 */
354 		(*ill->ill_inputfn)(mp, ip6h, &ip6h->ip6_dst, &iras, &rtc);
355 
356 		/* Any references to clean up? No hold on ira_ill */
357 		if (iras.ira_flags & (IRAF_IPSEC_SECURE|IRAF_SYSTEM_LABELED))
358 			ira_cleanup(&iras, B_FALSE);
359 
360 		if (iras.ira_target_sqp_mp != NULL) {
361 			/* Better be called from ip_accept_tcp */
362 			ASSERT(target_sqp != NULL);
363 
364 			/* Found one packet to accept */
365 			mp = iras.ira_target_sqp_mp;
366 			iras.ira_target_sqp_mp = NULL;
367 			ASSERT(ip_recv_attr_is_mblk(mp));
368 
369 			if (atail != NULL)
370 				atail->b_next = mp;
371 			else
372 				ahead = mp;
373 			atail = mp;
374 			acnt++;
375 			mp = NULL;
376 		}
377 		/* mhip might point into 1st packet in the chain. */
378 		iras.ira_mhip = NULL;
379 	}
380 	/* Any remaining references to the route cache? */
381 	if (rtc.rtc_ire != NULL) {
382 		ASSERT(!IN6_IS_ADDR_UNSPECIFIED(&rtc.rtc_ip6addr));
383 		ire_refrele(rtc.rtc_ire);
384 	}
385 
386 	if (ahead != NULL) {
387 		/* Better be called from ip_accept_tcp */
388 		ASSERT(target_sqp != NULL);
389 		*last = atail;
390 		*cnt = acnt;
391 		return (ahead);
392 	}
393 
394 	return (NULL);
395 }
396 
397 /*
398  * This input function is used when
399  *  - is_system_labeled()
400  *
401  * Note that for IPv6 CGTP filtering is handled only when receiving fragment
402  * headers, and RSVP uses router alert options, thus we don't need anything
403  * extra for them.
404  */
405 void
406 ill_input_full_v6(mblk_t *mp, void *iph_arg, void *nexthop_arg,
407     ip_recv_attr_t *ira, rtc_t *rtc)
408 {
409 	ip6_t		*ip6h = (ip6_t *)iph_arg;
410 	in6_addr_t	*nexthop = (in6_addr_t *)nexthop_arg;
411 	ill_t		*ill = ira->ira_ill;
412 
413 	ASSERT(ira->ira_tsl == NULL);
414 
415 	/*
416 	 * Attach any necessary label information to
417 	 * this packet
418 	 */
419 	if (is_system_labeled()) {
420 		ira->ira_flags |= IRAF_SYSTEM_LABELED;
421 
422 		/*
423 		 * This updates ira_cred, ira_tsl and ira_free_flags based
424 		 * on the label.
425 		 */
426 		if (!tsol_get_pkt_label(mp, IPV6_VERSION, ira)) {
427 			if (ip6opt_ls != 0)
428 				ip0dbg(("tsol_get_pkt_label v6 failed\n"));
429 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsInDiscards);
430 			ip_drop_input("ipIfStatsInDiscards", mp, ill);
431 			freemsg(mp);
432 			return;
433 		}
434 		/* Note that ira_tsl can be NULL here. */
435 
436 		/* tsol_get_pkt_label sometimes does pullupmsg */
437 		ip6h = (ip6_t *)mp->b_rptr;
438 	}
439 	ill_input_short_v6(mp, ip6h, nexthop, ira, rtc);
440 }
441 
442 /*
443  * Check for IPv6 addresses that should not appear on the wire
444  * as either source or destination.
445  * If we ever implement Stateless IPv6 Translators (SIIT) we'd have
446  * to revisit the IPv4-mapped part.
447  */
448 static boolean_t
449 ip6_bad_address(in6_addr_t *addr, boolean_t is_src)
450 {
451 	if (IN6_IS_ADDR_V4MAPPED(addr)) {
452 		ip1dbg(("ip_input_v6: pkt with IPv4-mapped addr"));
453 		return (B_TRUE);
454 	}
455 	if (IN6_IS_ADDR_LOOPBACK(addr)) {
456 		ip1dbg(("ip_input_v6: pkt with loopback addr"));
457 		return (B_TRUE);
458 	}
459 	if (!is_src && IN6_IS_ADDR_UNSPECIFIED(addr)) {
460 		/*
461 		 * having :: in the src is ok: it's used for DAD.
462 		 */
463 		ip1dbg(("ip_input_v6: pkt with unspecified addr"));
464 		return (B_TRUE);
465 	}
466 	return (B_FALSE);
467 }
468 
469 /*
470  * Routing lookup for IPv6 link-locals.
471  * First we look on the inbound interface, then we check for IPMP and
472  * look on the upper interface.
473  * We update ira_ruifindex if we find the IRE on the upper interface.
474  */
475 static ire_t *
476 ire_linklocal(const in6_addr_t *nexthop, ill_t *ill, ip_recv_attr_t *ira,
477     uint_t irr_flags, ip_stack_t *ipst)
478 {
479 	int match_flags = MATCH_IRE_SECATTR | MATCH_IRE_ILL;
480 	ire_t *ire;
481 
482 	ASSERT(IN6_IS_ADDR_LINKLOCAL(nexthop));
483 	ire = ire_route_recursive_v6(nexthop, 0, ill, ALL_ZONES, ira->ira_tsl,
484 	    match_flags, irr_flags, ira->ira_xmit_hint, ipst, NULL, NULL, NULL);
485 	if (!(ire->ire_flags & (RTF_REJECT|RTF_BLACKHOLE)) ||
486 	    !IS_UNDER_IPMP(ill))
487 		return (ire);
488 
489 	/*
490 	 * When we are using IMP we need to look for an IRE on both the
491 	 * under and upper interfaces since there are different
492 	 * link-local addresses for the under and upper.
493 	 */
494 	ill = ipmp_ill_hold_ipmp_ill(ill);
495 	if (ill == NULL)
496 		return (ire);
497 
498 	ira->ira_ruifindex = ill->ill_phyint->phyint_ifindex;
499 
500 	ire_refrele(ire);
501 	ire = ire_route_recursive_v6(nexthop, 0, ill, ALL_ZONES, ira->ira_tsl,
502 	    match_flags, irr_flags, ira->ira_xmit_hint, ipst, NULL, NULL, NULL);
503 	ill_refrele(ill);
504 	return (ire);
505 }
506 
507 /*
508  * This is the tail-end of the full receive side packet handling.
509  * It can be used directly when the configuration is simple.
510  */
511 void
512 ill_input_short_v6(mblk_t *mp, void *iph_arg, void *nexthop_arg,
513     ip_recv_attr_t *ira, rtc_t *rtc)
514 {
515 	ire_t		*ire;
516 	ill_t		*ill = ira->ira_ill;
517 	ip_stack_t	*ipst = ill->ill_ipst;
518 	uint_t		pkt_len;
519 	ssize_t 	len;
520 	ip6_t		*ip6h = (ip6_t *)iph_arg;
521 	in6_addr_t	nexthop = *(in6_addr_t *)nexthop_arg;
522 	ilb_stack_t	*ilbs = ipst->ips_netstack->netstack_ilb;
523 	uint_t		irr_flags;
524 #define	rptr	((uchar_t *)ip6h)
525 
526 	ASSERT(DB_TYPE(mp) == M_DATA);
527 
528 	/*
529 	 * Check for source/dest being a bad address: loopback, any, or
530 	 * v4mapped. All of them start with a 64 bits of zero.
531 	 */
532 	if (ip6h->ip6_src.s6_addr32[0] == 0 &&
533 	    ip6h->ip6_src.s6_addr32[1] == 0) {
534 		if (ip6_bad_address(&ip6h->ip6_src, B_TRUE)) {
535 			ip1dbg(("ip_input_v6: pkt with bad src addr\n"));
536 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsInAddrErrors);
537 			ip_drop_input("ipIfStatsInAddrErrors", mp, ill);
538 			freemsg(mp);
539 			return;
540 		}
541 	}
542 	if (ip6h->ip6_dst.s6_addr32[0] == 0 &&
543 	    ip6h->ip6_dst.s6_addr32[1] == 0) {
544 		if (ip6_bad_address(&ip6h->ip6_dst, B_FALSE)) {
545 			ip1dbg(("ip_input_v6: pkt with bad dst addr\n"));
546 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsInAddrErrors);
547 			ip_drop_input("ipIfStatsInAddrErrors", mp, ill);
548 			freemsg(mp);
549 			return;
550 		}
551 	}
552 
553 	len = mp->b_wptr - rptr;
554 	pkt_len = ira->ira_pktlen;
555 
556 	/* multiple mblk or too short */
557 	len -= pkt_len;
558 	if (len != 0) {
559 		mp = ip_check_length(mp, rptr, len, pkt_len, IPV6_HDR_LEN, ira);
560 		if (mp == NULL)
561 			return;
562 		ip6h = (ip6_t *)mp->b_rptr;
563 	}
564 
565 	DTRACE_IP7(receive, mblk_t *, mp, conn_t *, NULL, void_ip_t *,
566 	    ip6h, __dtrace_ipsr_ill_t *, ill, ipha_t *, NULL, ip6_t *, ip6h,
567 	    int, 0);
568 	/*
569 	 * The event for packets being received from a 'physical'
570 	 * interface is placed after validation of the source and/or
571 	 * destination address as being local so that packets can be
572 	 * redirected to loopback addresses using ipnat.
573 	 */
574 	DTRACE_PROBE4(ip6__physical__in__start,
575 	    ill_t *, ill, ill_t *, NULL,
576 	    ip6_t *, ip6h, mblk_t *, mp);
577 
578 	if (HOOKS6_INTERESTED_PHYSICAL_IN(ipst)) {
579 		int	ll_multicast = 0;
580 		int	error;
581 		in6_addr_t orig_dst = ip6h->ip6_dst;
582 
583 		if (ira->ira_flags & IRAF_L2DST_MULTICAST)
584 			ll_multicast = HPE_MULTICAST;
585 		else if (ira->ira_flags & IRAF_L2DST_BROADCAST)
586 			ll_multicast = HPE_BROADCAST;
587 
588 		FW_HOOKS6(ipst->ips_ip6_physical_in_event,
589 		    ipst->ips_ipv6firewall_physical_in,
590 		    ill, NULL, ip6h, mp, mp, ll_multicast, ipst, error);
591 
592 		DTRACE_PROBE1(ip6__physical__in__end, mblk_t *, mp);
593 
594 		if (mp == NULL)
595 			return;
596 
597 		/* The length could have changed */
598 		ip6h = (ip6_t *)mp->b_rptr;
599 		ira->ira_pktlen = ntohs(ip6h->ip6_plen) + IPV6_HDR_LEN;
600 		pkt_len = ira->ira_pktlen;
601 
602 		/*
603 		 * In case the destination changed we override any previous
604 		 * change to nexthop.
605 		 */
606 		if (!IN6_ARE_ADDR_EQUAL(&orig_dst, &ip6h->ip6_dst))
607 			nexthop = ip6h->ip6_dst;
608 
609 		if (IN6_IS_ADDR_UNSPECIFIED(&nexthop)) {
610 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsInAddrErrors);
611 			ip_drop_input("ipIfStatsInAddrErrors", mp, ill);
612 			freemsg(mp);
613 			return;
614 		}
615 
616 	}
617 
618 	if (ipst->ips_ip6_observe.he_interested) {
619 		zoneid_t dzone;
620 
621 		/*
622 		 * On the inbound path the src zone will be unknown as
623 		 * this packet has come from the wire.
624 		 */
625 		dzone = ip_get_zoneid_v6(&nexthop, mp, ill, ira, ALL_ZONES);
626 		ipobs_hook(mp, IPOBS_HOOK_INBOUND, ALL_ZONES, dzone, ill, ipst);
627 	}
628 
629 	if ((ip6h->ip6_vcf & IPV6_VERS_AND_FLOW_MASK) !=
630 	    IPV6_DEFAULT_VERS_AND_FLOW) {
631 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsInHdrErrors);
632 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsInWrongIPVersion);
633 		ip_drop_input("ipIfStatsInWrongIPVersion", mp, ill);
634 		freemsg(mp);
635 		return;
636 	}
637 
638 	/*
639 	 * For IPv6 we update ira_ip_hdr_length and ira_protocol as
640 	 * we parse the headers, starting with the hop-by-hop options header.
641 	 */
642 	ira->ira_ip_hdr_length = IPV6_HDR_LEN;
643 	if ((ira->ira_protocol = ip6h->ip6_nxt) == IPPROTO_HOPOPTS) {
644 		ip6_hbh_t	*hbhhdr;
645 		uint_t		ehdrlen;
646 		uint8_t		*optptr;
647 
648 		if (pkt_len < IPV6_HDR_LEN + MIN_EHDR_LEN) {
649 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsInTruncatedPkts);
650 			ip_drop_input("ipIfStatsInTruncatedPkts", mp, ill);
651 			freemsg(mp);
652 			return;
653 		}
654 		if (mp->b_cont != NULL &&
655 		    rptr + IPV6_HDR_LEN + MIN_EHDR_LEN > mp->b_wptr) {
656 			ip6h = ip_pullup(mp, IPV6_HDR_LEN + MIN_EHDR_LEN, ira);
657 			if (ip6h == NULL) {
658 				BUMP_MIB(ill->ill_ip_mib, ipIfStatsInDiscards);
659 				ip_drop_input("ipIfStatsInDiscards", mp, ill);
660 				freemsg(mp);
661 				return;
662 			}
663 		}
664 		hbhhdr = (ip6_hbh_t *)&ip6h[1];
665 		ehdrlen = 8 * (hbhhdr->ip6h_len + 1);
666 
667 		if (pkt_len < IPV6_HDR_LEN + ehdrlen) {
668 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsInTruncatedPkts);
669 			ip_drop_input("ipIfStatsInTruncatedPkts", mp, ill);
670 			freemsg(mp);
671 			return;
672 		}
673 		if (mp->b_cont != NULL &&
674 		    rptr + IPV6_HDR_LEN + ehdrlen > mp->b_wptr) {
675 			ip6h = ip_pullup(mp, IPV6_HDR_LEN + ehdrlen, ira);
676 			if (ip6h == NULL) {
677 				BUMP_MIB(ill->ill_ip_mib, ipIfStatsInDiscards);
678 				ip_drop_input("ipIfStatsInDiscards", mp, ill);
679 				freemsg(mp);
680 				return;
681 			}
682 			hbhhdr = (ip6_hbh_t *)&ip6h[1];
683 		}
684 
685 		/*
686 		 * Update ira_ip_hdr_length to skip the hop-by-hop header
687 		 * once we get to ip_fanout_v6
688 		 */
689 		ira->ira_ip_hdr_length += ehdrlen;
690 		ira->ira_protocol = hbhhdr->ip6h_nxt;
691 
692 		optptr = (uint8_t *)&hbhhdr[1];
693 		switch (ip_process_options_v6(mp, ip6h, optptr,
694 		    ehdrlen - 2, IPPROTO_HOPOPTS, ira)) {
695 		case -1:
696 			/*
697 			 * Packet has been consumed and any
698 			 * needed ICMP messages sent.
699 			 */
700 			return;
701 		case 0:
702 			/* no action needed */
703 			break;
704 		case 1:
705 			/*
706 			 * Known router alert. Make use handle it as local
707 			 * by setting the nexthop to be the all-host multicast
708 			 * address, and skip multicast membership filter by
709 			 * marking as a router alert.
710 			 */
711 			ira->ira_flags |= IRAF_ROUTER_ALERT;
712 			nexthop = ipv6_all_hosts_mcast;
713 			break;
714 		}
715 	}
716 
717 	/*
718 	 * Here we check to see if we machine is setup as
719 	 * L3 loadbalancer and if the incoming packet is for a VIP
720 	 *
721 	 * Check the following:
722 	 * - there is at least a rule
723 	 * - protocol of the packet is supported
724 	 *
725 	 * We don't load balance IPv6 link-locals.
726 	 */
727 	if (ilb_has_rules(ilbs) && ILB_SUPP_L4(ira->ira_protocol) &&
728 	    !IN6_IS_ADDR_LINKLOCAL(&nexthop)) {
729 		in6_addr_t	lb_dst;
730 		int		lb_ret;
731 
732 		/* For convenience, we just pull up the mblk. */
733 		if (mp->b_cont != NULL) {
734 			if (pullupmsg(mp, -1) == 0) {
735 				BUMP_MIB(ill->ill_ip_mib, ipIfStatsInDiscards);
736 				ip_drop_input("ipIfStatsInDiscards - pullupmsg",
737 				    mp, ill);
738 				freemsg(mp);
739 				return;
740 			}
741 			ip6h = (ip6_t *)mp->b_rptr;
742 		}
743 		lb_ret = ilb_check_v6(ilbs, ill, mp, ip6h, ira->ira_protocol,
744 		    (uint8_t *)ip6h + ira->ira_ip_hdr_length, &lb_dst);
745 		if (lb_ret == ILB_DROPPED) {
746 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsInDiscards);
747 			ip_drop_input("ILB_DROPPED", mp, ill);
748 			freemsg(mp);
749 			return;
750 		}
751 		if (lb_ret == ILB_BALANCED) {
752 			/* Set the dst to that of the chosen server */
753 			nexthop = lb_dst;
754 			DB_CKSUMFLAGS(mp) = 0;
755 		}
756 	}
757 
758 	if (ill->ill_flags & ILLF_ROUTER)
759 		irr_flags = IRR_ALLOCATE;
760 	else
761 		irr_flags = IRR_NONE;
762 
763 	/* Can not use route cache with TX since the labels can differ */
764 	if (ira->ira_flags & IRAF_SYSTEM_LABELED) {
765 		if (IN6_IS_ADDR_MULTICAST(&nexthop)) {
766 			ire = ire_multicast(ill);
767 		} else if (IN6_IS_ADDR_LINKLOCAL(&nexthop)) {
768 			ire = ire_linklocal(&nexthop, ill, ira, irr_flags,
769 			    ipst);
770 		} else {
771 			/* Match destination and label */
772 			ire = ire_route_recursive_v6(&nexthop, 0, NULL,
773 			    ALL_ZONES, ira->ira_tsl, MATCH_IRE_SECATTR,
774 			    irr_flags, ira->ira_xmit_hint, ipst, NULL, NULL,
775 			    NULL);
776 		}
777 		/* Update the route cache so we do the ire_refrele */
778 		ASSERT(ire != NULL);
779 		if (rtc->rtc_ire != NULL)
780 			ire_refrele(rtc->rtc_ire);
781 		rtc->rtc_ire = ire;
782 		rtc->rtc_ip6addr = nexthop;
783 	} else if (IN6_ARE_ADDR_EQUAL(&nexthop, &rtc->rtc_ip6addr)) {
784 		/* Use the route cache */
785 		ASSERT(rtc->rtc_ire != NULL);
786 		ire = rtc->rtc_ire;
787 	} else {
788 		/* Update the route cache */
789 		if (IN6_IS_ADDR_MULTICAST(&nexthop)) {
790 			ire = ire_multicast(ill);
791 		} else if (IN6_IS_ADDR_LINKLOCAL(&nexthop)) {
792 			ire = ire_linklocal(&nexthop, ill, ira, irr_flags,
793 			    ipst);
794 		} else {
795 			ire = ire_route_recursive_dstonly_v6(&nexthop,
796 			    irr_flags, ira->ira_xmit_hint, ipst);
797 		}
798 		ASSERT(ire != NULL);
799 		if (rtc->rtc_ire != NULL)
800 			ire_refrele(rtc->rtc_ire);
801 		rtc->rtc_ire = ire;
802 		rtc->rtc_ip6addr = nexthop;
803 	}
804 
805 	ire->ire_ib_pkt_count++;
806 
807 	/*
808 	 * Based on ire_type and ire_flags call one of:
809 	 *	ire_recv_local_v6 - for IRE_LOCAL
810 	 *	ire_recv_loopback_v6 - for IRE_LOOPBACK
811 	 *	ire_recv_multirt_v6 - if RTF_MULTIRT
812 	 *	ire_recv_noroute_v6 - if RTF_REJECT or RTF_BLACHOLE
813 	 *	ire_recv_multicast_v6 - for IRE_MULTICAST
814 	 *	ire_recv_noaccept_v6 - for ire_noaccept ones
815 	 *	ire_recv_forward_v6 - for the rest.
816 	 */
817 
818 	(*ire->ire_recvfn)(ire, mp, ip6h, ira);
819 }
820 #undef rptr
821 
822 /*
823  * ire_recvfn for IREs that need forwarding
824  */
825 void
826 ire_recv_forward_v6(ire_t *ire, mblk_t *mp, void *iph_arg, ip_recv_attr_t *ira)
827 {
828 	ip6_t		*ip6h = (ip6_t *)iph_arg;
829 	ill_t		*ill = ira->ira_ill;
830 	ip_stack_t	*ipst = ill->ill_ipst;
831 	iaflags_t	iraflags = ira->ira_flags;
832 	ill_t		*dst_ill;
833 	nce_t		*nce;
834 	uint32_t	added_tx_len;
835 	uint32_t	mtu, iremtu;
836 
837 	if (iraflags & (IRAF_L2DST_MULTICAST|IRAF_L2DST_BROADCAST)) {
838 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsForwProhibits);
839 		ip_drop_input("l2 multicast not forwarded", mp, ill);
840 		freemsg(mp);
841 		return;
842 	}
843 
844 	if (!(ill->ill_flags & ILLF_ROUTER)) {
845 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsForwProhibits);
846 		ip_drop_input("ipIfStatsForwProhibits", mp, ill);
847 		freemsg(mp);
848 		return;
849 	}
850 
851 	/*
852 	 * Either ire_nce_capable or ire_dep_parent would be set for the IRE
853 	 * when it is found by ire_route_recursive, but that some other thread
854 	 * could have changed the routes with the effect of clearing
855 	 * ire_dep_parent. In that case we'd end up dropping the packet, or
856 	 * finding a new nce below.
857 	 * Get, allocate, or update the nce.
858 	 * We get a refhold on ire_nce_cache as a result of this to avoid races
859 	 * where ire_nce_cache is deleted.
860 	 *
861 	 * This ensures that we don't forward if the interface is down since
862 	 * ipif_down removes all the nces.
863 	 */
864 	mutex_enter(&ire->ire_lock);
865 	nce = ire->ire_nce_cache;
866 	if (nce == NULL) {
867 		/* Not yet set up - try to set one up */
868 		mutex_exit(&ire->ire_lock);
869 		(void) ire_revalidate_nce(ire);
870 		mutex_enter(&ire->ire_lock);
871 		nce = ire->ire_nce_cache;
872 		if (nce == NULL) {
873 			mutex_exit(&ire->ire_lock);
874 			/* The ire_dep_parent chain went bad, or no memory */
875 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsInDiscards);
876 			ip_drop_input("No ire_dep_parent", mp, ill);
877 			freemsg(mp);
878 			return;
879 		}
880 	}
881 	nce_refhold(nce);
882 	mutex_exit(&ire->ire_lock);
883 
884 	if (nce->nce_is_condemned) {
885 		nce_t *nce1;
886 
887 		nce1 = ire_handle_condemned_nce(nce, ire, NULL, ip6h, B_FALSE);
888 		nce_refrele(nce);
889 		if (nce1 == NULL) {
890 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsInDiscards);
891 			ip_drop_input("No nce", mp, ill);
892 			freemsg(mp);
893 			return;
894 		}
895 		nce = nce1;
896 	}
897 	dst_ill = nce->nce_ill;
898 
899 	/*
900 	 * Unless we are forwarding, drop the packet.
901 	 * Unlike IPv4 we don't allow source routed packets out the same
902 	 * interface when we are not a router.
903 	 * Note that ill_forward_set() will set the ILLF_ROUTER on
904 	 * all the group members when it gets an ipmp-ill or under-ill.
905 	 */
906 	if (!(dst_ill->ill_flags & ILLF_ROUTER)) {
907 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsForwProhibits);
908 		ip_drop_input("ipIfStatsForwProhibits", mp, ill);
909 		freemsg(mp);
910 		nce_refrele(nce);
911 		return;
912 	}
913 
914 	if (ire->ire_zoneid != GLOBAL_ZONEID && ire->ire_zoneid != ALL_ZONES) {
915 		ire->ire_ib_pkt_count--;
916 		/*
917 		 * Should only use IREs that are visible from the
918 		 * global zone for forwarding.
919 		 * For IPv6 any source route would have already been
920 		 * advanced in ip_fanout_v6
921 		 */
922 		ire = ire_route_recursive_v6(&ip6h->ip6_dst, 0, NULL,
923 		    GLOBAL_ZONEID, ira->ira_tsl, MATCH_IRE_SECATTR,
924 		    (ill->ill_flags & ILLF_ROUTER) ? IRR_ALLOCATE : IRR_NONE,
925 		    ira->ira_xmit_hint, ipst, NULL, NULL, NULL);
926 		ire->ire_ib_pkt_count++;
927 		(*ire->ire_recvfn)(ire, mp, ip6h, ira);
928 		ire_refrele(ire);
929 		nce_refrele(nce);
930 		return;
931 	}
932 	/*
933 	 * ipIfStatsHCInForwDatagrams should only be increment if there
934 	 * will be an attempt to forward the packet, which is why we
935 	 * increment after the above condition has been checked.
936 	 */
937 	BUMP_MIB(ill->ill_ip_mib, ipIfStatsHCInForwDatagrams);
938 
939 	/* Initiate Read side IPPF processing */
940 	if (IPP_ENABLED(IPP_FWD_IN, ipst)) {
941 		/* ip_process translates an IS_UNDER_IPMP */
942 		mp = ip_process(IPP_FWD_IN, mp, ill, ill);
943 		if (mp == NULL) {
944 			/* ip_drop_packet and MIB done */
945 			ip2dbg(("ire_recv_forward_v6: pkt dropped/deferred "
946 			    "during IPPF processing\n"));
947 			nce_refrele(nce);
948 			return;
949 		}
950 	}
951 
952 	DTRACE_PROBE4(ip6__forwarding__start,
953 	    ill_t *, ill, ill_t *, dst_ill, ip6_t *, ip6h, mblk_t *, mp);
954 
955 	if (HOOKS6_INTERESTED_FORWARDING(ipst)) {
956 		int	error;
957 
958 		FW_HOOKS(ipst->ips_ip6_forwarding_event,
959 		    ipst->ips_ipv6firewall_forwarding,
960 		    ill, dst_ill, ip6h, mp, mp, 0, ipst, error);
961 
962 		DTRACE_PROBE1(ip6__forwarding__end, mblk_t *, mp);
963 
964 		if (mp == NULL) {
965 			nce_refrele(nce);
966 			return;
967 		}
968 		/*
969 		 * Even if the destination was changed by the filter we use the
970 		 * forwarding decision that was made based on the address
971 		 * in ip_input.
972 		 */
973 
974 		/* Might have changed */
975 		ip6h = (ip6_t *)mp->b_rptr;
976 		ira->ira_pktlen = ntohs(ip6h->ip6_plen) + IPV6_HDR_LEN;
977 	}
978 
979 	/* Packet is being forwarded. Turning off hwcksum flag. */
980 	DB_CKSUMFLAGS(mp) = 0;
981 
982 	/*
983 	 * Per RFC 3513 section 2.5.2, we must not forward packets with
984 	 * an unspecified source address.
985 	 * The loopback address check for both src and dst has already
986 	 * been checked in ip_input_v6
987 	 * In the future one can envision adding RPF checks using number 3.
988 	 */
989 	switch (ipst->ips_src_check) {
990 	case 0:
991 		break;
992 	case 1:
993 	case 2:
994 		if (IN6_IS_ADDR_UNSPECIFIED(&ip6h->ip6_src) ||
995 		    IN6_IS_ADDR_MULTICAST(&ip6h->ip6_src)) {
996 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsForwProhibits);
997 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsInAddrErrors);
998 			ip_drop_input("ipIfStatsInAddrErrors", mp, ill);
999 			nce_refrele(nce);
1000 			freemsg(mp);
1001 			return;
1002 		}
1003 		break;
1004 	}
1005 
1006 	/*
1007 	 * Check to see if we're forwarding the packet to a
1008 	 * different link from which it came.  If so, check the
1009 	 * source and destination addresses since routers must not
1010 	 * forward any packets with link-local source or
1011 	 * destination addresses to other links.  Otherwise (if
1012 	 * we're forwarding onto the same link), conditionally send
1013 	 * a redirect message.
1014 	 */
1015 	if (!IS_ON_SAME_LAN(dst_ill, ill)) {
1016 		if (IN6_IS_ADDR_LINKLOCAL(&ip6h->ip6_dst) ||
1017 		    IN6_IS_ADDR_LINKLOCAL(&ip6h->ip6_src)) {
1018 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsInAddrErrors);
1019 			ip_drop_input("ipIfStatsInAddrErrors", mp, ill);
1020 			freemsg(mp);
1021 			nce_refrele(nce);
1022 			return;
1023 		}
1024 		/* TBD add site-local check at site boundary? */
1025 	} else if (ipst->ips_ipv6_send_redirects) {
1026 		ip_send_potential_redirect_v6(mp, ip6h, ire, ira);
1027 	}
1028 
1029 	added_tx_len = 0;
1030 	if (iraflags & IRAF_SYSTEM_LABELED) {
1031 		mblk_t		*mp1;
1032 		uint32_t	old_pkt_len = ira->ira_pktlen;
1033 
1034 		/*
1035 		 * Check if it can be forwarded and add/remove
1036 		 * CIPSO options as needed.
1037 		 */
1038 		if ((mp1 = tsol_ip_forward(ire, mp, ira)) == NULL) {
1039 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsForwProhibits);
1040 			ip_drop_input("tsol_ip_forward", mp, ill);
1041 			freemsg(mp);
1042 			nce_refrele(nce);
1043 			return;
1044 		}
1045 		/*
1046 		 * Size may have changed. Remember amount added in case
1047 		 * ip_fragment needs to send an ICMP too big.
1048 		 */
1049 		mp = mp1;
1050 		ip6h = (ip6_t *)mp->b_rptr;
1051 		ira->ira_pktlen = ntohs(ip6h->ip6_plen) + IPV6_HDR_LEN;
1052 		ira->ira_ip_hdr_length = IPV6_HDR_LEN;
1053 		if (ira->ira_pktlen > old_pkt_len)
1054 			added_tx_len = ira->ira_pktlen - old_pkt_len;
1055 	}
1056 
1057 	mtu = dst_ill->ill_mtu;
1058 	if ((iremtu = ire->ire_metrics.iulp_mtu) != 0 && iremtu < mtu)
1059 		mtu = iremtu;
1060 	ip_forward_xmit_v6(nce, mp, ip6h, ira, mtu, added_tx_len);
1061 	nce_refrele(nce);
1062 	return;
1063 
1064 }
1065 
1066 /*
1067  * Used for sending out unicast and multicast packets that are
1068  * forwarded.
1069  */
1070 void
1071 ip_forward_xmit_v6(nce_t *nce, mblk_t *mp, ip6_t *ip6h, ip_recv_attr_t *ira,
1072     uint32_t mtu, uint32_t added_tx_len)
1073 {
1074 	ill_t		*dst_ill = nce->nce_ill;
1075 	uint32_t	pkt_len;
1076 	iaflags_t	iraflags = ira->ira_flags;
1077 	ip_stack_t	*ipst = dst_ill->ill_ipst;
1078 
1079 	if (ip6h->ip6_hops-- <= 1) {
1080 		BUMP_MIB(ira->ira_ill->ill_ip_mib, ipIfStatsInDiscards);
1081 		ip_drop_input("ICMP6_TIME_EXCEED_TRANSIT", mp, ira->ira_ill);
1082 		icmp_time_exceeded_v6(mp, ICMP6_TIME_EXCEED_TRANSIT, B_FALSE,
1083 		    ira);
1084 		return;
1085 	}
1086 
1087 	/* Initiate Write side IPPF processing before any fragmentation */
1088 	if (IPP_ENABLED(IPP_FWD_OUT, ipst)) {
1089 		/* ip_process translates an IS_UNDER_IPMP */
1090 		mp = ip_process(IPP_FWD_OUT, mp, dst_ill, dst_ill);
1091 		if (mp == NULL) {
1092 			/* ip_drop_packet and MIB done */
1093 			ip2dbg(("ire_recv_forward_v6: pkt dropped/deferred" \
1094 			    " during IPPF processing\n"));
1095 			return;
1096 		}
1097 	}
1098 
1099 	pkt_len = ira->ira_pktlen;
1100 
1101 	BUMP_MIB(dst_ill->ill_ip_mib, ipIfStatsHCOutForwDatagrams);
1102 
1103 	if (pkt_len > mtu) {
1104 		BUMP_MIB(dst_ill->ill_ip_mib, ipIfStatsOutFragFails);
1105 		ip_drop_output("ipIfStatsOutFragFails", mp, dst_ill);
1106 		if (iraflags & IRAF_SYSTEM_LABELED) {
1107 			/*
1108 			 * Remove any CIPSO option added by
1109 			 * tsol_ip_forward, and make sure we report
1110 			 * a path MTU so that there
1111 			 * is room to add such a CIPSO option for future
1112 			 * packets.
1113 			 */
1114 			mtu = tsol_pmtu_adjust(mp, mtu, added_tx_len, AF_INET6);
1115 		}
1116 		icmp_pkt2big_v6(mp, mtu, B_TRUE, ira);
1117 		return;
1118 	}
1119 
1120 	ASSERT(pkt_len ==
1121 	    ntohs(((ip6_t *)mp->b_rptr)->ip6_plen) + IPV6_HDR_LEN);
1122 
1123 	if (iraflags & IRAF_LOOPBACK_COPY) {
1124 		/*
1125 		 * IXAF_NO_LOOP_ZONEID is not set hence 6th arg
1126 		 * is don't care
1127 		 */
1128 		(void) ip_postfrag_loopcheck(mp, nce,
1129 		    (IXAF_LOOPBACK_COPY | IXAF_NO_DEV_FLOW_CTL),
1130 		    pkt_len, ira->ira_xmit_hint, GLOBAL_ZONEID, 0, NULL);
1131 	} else {
1132 		(void) ip_xmit(mp, nce, IXAF_NO_DEV_FLOW_CTL,
1133 		    pkt_len, ira->ira_xmit_hint, GLOBAL_ZONEID, 0, NULL);
1134 	}
1135 }
1136 
1137 /*
1138  * ire_recvfn for RTF_REJECT and RTF_BLACKHOLE routes, including IRE_NOROUTE,
1139  * which is what ire_route_recursive returns when there is no matching ire.
1140  * Send ICMP unreachable unless blackhole.
1141  */
1142 void
1143 ire_recv_noroute_v6(ire_t *ire, mblk_t *mp, void *iph_arg, ip_recv_attr_t *ira)
1144 {
1145 	ip6_t		*ip6h = (ip6_t *)iph_arg;
1146 	ill_t		*ill = ira->ira_ill;
1147 	ip_stack_t	*ipst = ill->ill_ipst;
1148 
1149 	/* Would we have forwarded this packet if we had a route? */
1150 	if (ira->ira_flags & (IRAF_L2DST_MULTICAST|IRAF_L2DST_BROADCAST)) {
1151 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsForwProhibits);
1152 		ip_drop_input("l2 multicast not forwarded", mp, ill);
1153 		freemsg(mp);
1154 		return;
1155 	}
1156 
1157 	if (!(ill->ill_flags & ILLF_ROUTER)) {
1158 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsForwProhibits);
1159 		ip_drop_input("ipIfStatsForwProhibits", mp, ill);
1160 		freemsg(mp);
1161 		return;
1162 	}
1163 	/*
1164 	 * If we had a route this could have been forwarded. Count as such.
1165 	 *
1166 	 * ipIfStatsHCInForwDatagrams should only be increment if there
1167 	 * will be an attempt to forward the packet, which is why we
1168 	 * increment after the above condition has been checked.
1169 	 */
1170 	BUMP_MIB(ill->ill_ip_mib, ipIfStatsHCInForwDatagrams);
1171 
1172 	BUMP_MIB(ill->ill_ip_mib, ipIfStatsInNoRoutes);
1173 
1174 	ip_rts_change_v6(RTM_MISS, &ip6h->ip6_dst, 0, 0, 0, 0, 0, 0, RTA_DST,
1175 	    ipst);
1176 
1177 	if (ire->ire_flags & RTF_BLACKHOLE) {
1178 		ip_drop_input("ipIfStatsInNoRoutes RTF_BLACKHOLE", mp, ill);
1179 		freemsg(mp);
1180 	} else {
1181 		ip_drop_input("ipIfStatsInNoRoutes RTF_REJECT", mp, ill);
1182 
1183 		icmp_unreachable_v6(mp, ICMP6_DST_UNREACH_NOROUTE, B_FALSE,
1184 		    ira);
1185 	}
1186 }
1187 
1188 /*
1189  * ire_recvfn for IRE_LOCALs marked with ire_noaccept. Such IREs are used for
1190  * VRRP when in noaccept mode.
1191  * We silently drop packets except for Neighbor Solicitations and
1192  * Neighbor Advertisements.
1193  */
1194 void
1195 ire_recv_noaccept_v6(ire_t *ire, mblk_t *mp, void *iph_arg,
1196     ip_recv_attr_t *ira)
1197 {
1198 	ip6_t		*ip6h = (ip6_t *)iph_arg;
1199 	ill_t		*ill = ira->ira_ill;
1200 	icmp6_t		*icmp6;
1201 	int		ip_hdr_length;
1202 
1203 	if (ip6h->ip6_nxt != IPPROTO_ICMPV6) {
1204 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsInDiscards);
1205 		ip_drop_input("ipIfStatsInDiscards - noaccept", mp, ill);
1206 		freemsg(mp);
1207 		return;
1208 	}
1209 	ip_hdr_length = ira->ira_ip_hdr_length;
1210 	if ((mp->b_wptr - mp->b_rptr) < (ip_hdr_length + ICMP6_MINLEN)) {
1211 		if (ira->ira_pktlen < (ip_hdr_length + ICMP6_MINLEN)) {
1212 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsInTruncatedPkts);
1213 			ip_drop_input("ipIfStatsInTruncatedPkts", mp, ill);
1214 			freemsg(mp);
1215 			return;
1216 		}
1217 		ip6h = ip_pullup(mp, ip_hdr_length + ICMP6_MINLEN, ira);
1218 		if (ip6h == NULL) {
1219 			BUMP_MIB(ill->ill_icmp6_mib, ipv6IfIcmpInErrors);
1220 			freemsg(mp);
1221 			return;
1222 		}
1223 	}
1224 	icmp6 = (icmp6_t *)(&mp->b_rptr[ip_hdr_length]);
1225 
1226 	if (icmp6->icmp6_type != ND_NEIGHBOR_SOLICIT &&
1227 	    icmp6->icmp6_type != ND_NEIGHBOR_ADVERT) {
1228 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsInDiscards);
1229 		ip_drop_input("ipIfStatsInDiscards - noaccept", mp, ill);
1230 		freemsg(mp);
1231 		return;
1232 	}
1233 	ire_recv_local_v6(ire, mp, ip6h, ira);
1234 }
1235 
1236 /*
1237  * ire_recvfn for IRE_MULTICAST.
1238  */
1239 void
1240 ire_recv_multicast_v6(ire_t *ire, mblk_t *mp, void *iph_arg,
1241     ip_recv_attr_t *ira)
1242 {
1243 	ip6_t		*ip6h = (ip6_t *)iph_arg;
1244 	ill_t		*ill = ira->ira_ill;
1245 
1246 	ASSERT(ire->ire_ill == ira->ira_ill);
1247 
1248 	BUMP_MIB(ill->ill_ip_mib, ipIfStatsHCInMcastPkts);
1249 	UPDATE_MIB(ill->ill_ip_mib, ipIfStatsHCInMcastOctets, ira->ira_pktlen);
1250 
1251 	/* Tag for higher-level protocols */
1252 	ira->ira_flags |= IRAF_MULTICAST;
1253 
1254 	/*
1255 	 * So that we don't end up with dups, only one ill an IPMP group is
1256 	 * nominated to receive multicast traffic.
1257 	 * If we have no cast_ill we are liberal and accept everything.
1258 	 */
1259 	if (IS_UNDER_IPMP(ill)) {
1260 		ip_stack_t	*ipst = ill->ill_ipst;
1261 
1262 		/* For an under ill_grp can change under lock */
1263 		rw_enter(&ipst->ips_ill_g_lock, RW_READER);
1264 		if (!ill->ill_nom_cast && ill->ill_grp != NULL &&
1265 		    ill->ill_grp->ig_cast_ill != NULL) {
1266 			rw_exit(&ipst->ips_ill_g_lock);
1267 			ip_drop_input("not on cast ill", mp, ill);
1268 			freemsg(mp);
1269 			return;
1270 		}
1271 		rw_exit(&ipst->ips_ill_g_lock);
1272 		/*
1273 		 * We switch to the upper ill so that mrouter and hasmembers
1274 		 * can operate on upper here and in ip_input_multicast.
1275 		 */
1276 		ill = ipmp_ill_hold_ipmp_ill(ill);
1277 		if (ill != NULL) {
1278 			ASSERT(ill != ira->ira_ill);
1279 			ASSERT(ire->ire_ill == ira->ira_ill);
1280 			ira->ira_ill = ill;
1281 			ira->ira_ruifindex = ill->ill_phyint->phyint_ifindex;
1282 		} else {
1283 			ill = ira->ira_ill;
1284 		}
1285 	}
1286 
1287 #ifdef notdef
1288 	/*
1289 	 * Check if we are a multicast router - send ip_mforward a copy of
1290 	 * the packet.
1291 	 * Due to mroute_decap tunnels we consider forwarding packets even if
1292 	 * mrouted has not joined the allmulti group on this interface.
1293 	 */
1294 	if (ipst->ips_ip_g_mrouter) {
1295 		int retval;
1296 
1297 		/*
1298 		 * Clear the indication that this may have hardware
1299 		 * checksum as we are not using it for forwarding.
1300 		 */
1301 		DB_CKSUMFLAGS(mp) = 0;
1302 
1303 		/*
1304 		 * ip_mforward helps us make these distinctions: If received
1305 		 * on tunnel and not IGMP, then drop.
1306 		 * If IGMP packet, then don't check membership
1307 		 * If received on a phyint and IGMP or PIM, then
1308 		 * don't check membership
1309 		 */
1310 		retval = ip_mforward_v6(mp, ira);
1311 		/* ip_mforward updates mib variables if needed */
1312 
1313 		switch (retval) {
1314 		case 0:
1315 			/*
1316 			 * pkt is okay and arrived on phyint.
1317 			 */
1318 			break;
1319 		case -1:
1320 			/* pkt is mal-formed, toss it */
1321 			freemsg(mp);
1322 			goto done;
1323 		case 1:
1324 			/*
1325 			 * pkt is okay and arrived on a tunnel
1326 			 *
1327 			 * If we are running a multicast router
1328 			 * we need to see all mld packets, which
1329 			 * are marked with router alerts.
1330 			 */
1331 			if (ira->ira_flags & IRAF_ROUTER_ALERT)
1332 				goto forus;
1333 			ip_drop_input("Multicast on tunnel ignored", mp, ill);
1334 			freemsg(mp);
1335 			goto done;
1336 		}
1337 	}
1338 #endif /* notdef */
1339 
1340 	/*
1341 	 * If this was a router alert we skip the group membership check.
1342 	 */
1343 	if (ira->ira_flags & IRAF_ROUTER_ALERT)
1344 		goto forus;
1345 
1346 	/*
1347 	 * Check if we have members on this ill. This is not necessary for
1348 	 * correctness because even if the NIC/GLD had a leaky filter, we
1349 	 * filter before passing to each conn_t.
1350 	 */
1351 	if (!ill_hasmembers_v6(ill, &ip6h->ip6_dst)) {
1352 		/*
1353 		 * Nobody interested
1354 		 *
1355 		 * This might just be caused by the fact that
1356 		 * multiple IP Multicast addresses map to the same
1357 		 * link layer multicast - no need to increment counter!
1358 		 */
1359 		ip_drop_input("Multicast with no members", mp, ill);
1360 		freemsg(mp);
1361 		goto done;
1362 	}
1363 forus:
1364 	ip2dbg(("ire_recv_multicast_v6: multicast for us\n"));
1365 
1366 	/*
1367 	 * After reassembly and IPsec we will need to duplicate the
1368 	 * multicast packet for all matching zones on the ill.
1369 	 */
1370 	ira->ira_zoneid = ALL_ZONES;
1371 
1372 	/* Reassemble on the ill on which the packet arrived */
1373 	ip_input_local_v6(ire, mp, ip6h, ira);
1374 done:
1375 	if (ill != ire->ire_ill) {
1376 		ill_refrele(ill);
1377 		ira->ira_ill = ire->ire_ill;
1378 		ira->ira_ruifindex = ira->ira_ill->ill_phyint->phyint_ifindex;
1379 	}
1380 }
1381 
1382 /*
1383  * ire_recvfn for IRE_OFFLINK with RTF_MULTIRT.
1384  * Drop packets since we don't forward out multirt routes.
1385  */
1386 /* ARGSUSED */
1387 void
1388 ire_recv_multirt_v6(ire_t *ire, mblk_t *mp, void *iph_arg, ip_recv_attr_t *ira)
1389 {
1390 	ill_t		*ill = ira->ira_ill;
1391 
1392 	BUMP_MIB(ill->ill_ip_mib, ipIfStatsInNoRoutes);
1393 	ip_drop_input("Not forwarding out MULTIRT", mp, ill);
1394 	freemsg(mp);
1395 }
1396 
1397 /*
1398  * ire_recvfn for IRE_LOOPBACK. This is only used when a FW_HOOK
1399  * has rewritten the packet to have a loopback destination address (We
1400  * filter out packet with a loopback destination from arriving over the wire).
1401  * We don't know what zone to use, thus we always use the GLOBAL_ZONEID.
1402  */
1403 void
1404 ire_recv_loopback_v6(ire_t *ire, mblk_t *mp, void *iph_arg, ip_recv_attr_t *ira)
1405 {
1406 	ip6_t		*ip6h = (ip6_t *)iph_arg;
1407 	ill_t		*ill = ira->ira_ill;
1408 	ill_t		*ire_ill = ire->ire_ill;
1409 
1410 	ira->ira_zoneid = GLOBAL_ZONEID;
1411 
1412 	/* Switch to the lo0 ill for further processing  */
1413 	if (ire_ill != ill) {
1414 		/*
1415 		 * Update ira_ill to be the ILL on which the IP address
1416 		 * is hosted.
1417 		 * No need to hold the ill since we have a hold on the ire
1418 		 */
1419 		ASSERT(ira->ira_ill == ira->ira_rill);
1420 		ira->ira_ill = ire_ill;
1421 
1422 		ip_input_local_v6(ire, mp, ip6h, ira);
1423 
1424 		/* Restore */
1425 		ASSERT(ira->ira_ill == ire_ill);
1426 		ira->ira_ill = ill;
1427 		return;
1428 
1429 	}
1430 	ip_input_local_v6(ire, mp, ip6h, ira);
1431 }
1432 
1433 /*
1434  * ire_recvfn for IRE_LOCAL.
1435  */
1436 void
1437 ire_recv_local_v6(ire_t *ire, mblk_t *mp, void *iph_arg, ip_recv_attr_t *ira)
1438 {
1439 	ip6_t		*ip6h = (ip6_t *)iph_arg;
1440 	ill_t		*ill = ira->ira_ill;
1441 	ill_t		*ire_ill = ire->ire_ill;
1442 
1443 	/* Make a note for DAD that this address is in use */
1444 	ire->ire_last_used_time = LBOLT_FASTPATH;
1445 
1446 	/* Only target the IRE_LOCAL with the right zoneid. */
1447 	ira->ira_zoneid = ire->ire_zoneid;
1448 
1449 	/*
1450 	 * If the packet arrived on the wrong ill, we check that
1451 	 * this is ok.
1452 	 * If it is, then we ensure that we do the reassembly on
1453 	 * the ill on which the address is hosted. We keep ira_rill as
1454 	 * the one on which the packet arrived, so that IP_PKTINFO and
1455 	 * friends can report this.
1456 	 */
1457 	if (ire_ill != ill) {
1458 		ire_t *new_ire;
1459 
1460 		new_ire = ip_check_multihome(&ip6h->ip6_dst, ire, ill);
1461 		if (new_ire == NULL) {
1462 			/* Drop packet */
1463 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsForwProhibits);
1464 			ip_drop_input("ipIfStatsInForwProhibits", mp, ill);
1465 			freemsg(mp);
1466 			return;
1467 		}
1468 		/*
1469 		 * Update ira_ill to be the ILL on which the IP address
1470 		 * is hosted. No need to hold the ill since we have a
1471 		 * hold on the ire. Note that we do the switch even if
1472 		 * new_ire == ire (for IPMP, ire would be the one corresponding
1473 		 * to the IPMP ill).
1474 		 */
1475 		ASSERT(ira->ira_ill == ira->ira_rill);
1476 		ira->ira_ill = new_ire->ire_ill;
1477 
1478 		/* ira_ruifindex tracks the upper for ira_rill */
1479 		if (IS_UNDER_IPMP(ill))
1480 			ira->ira_ruifindex = ill_get_upper_ifindex(ill);
1481 
1482 		ip_input_local_v6(new_ire, mp, ip6h, ira);
1483 
1484 		/* Restore */
1485 		ASSERT(ira->ira_ill == new_ire->ire_ill);
1486 		ira->ira_ill = ill;
1487 		ira->ira_ruifindex = ill->ill_phyint->phyint_ifindex;
1488 
1489 		if (new_ire != ire)
1490 			ire_refrele(new_ire);
1491 		return;
1492 	}
1493 
1494 	ip_input_local_v6(ire, mp, ip6h, ira);
1495 }
1496 
1497 /*
1498  * Common function for packets arriving for the host. Handles
1499  * checksum verification, reassembly checks, etc.
1500  */
1501 static void
1502 ip_input_local_v6(ire_t *ire, mblk_t *mp, ip6_t *ip6h, ip_recv_attr_t *ira)
1503 {
1504 	iaflags_t	iraflags = ira->ira_flags;
1505 
1506 	/*
1507 	 * For multicast we need some extra work before
1508 	 * we call ip_fanout_v6(), since in the case of shared-IP zones
1509 	 * we need to pretend that a packet arrived for each zoneid.
1510 	 */
1511 	if (iraflags & IRAF_MULTICAST) {
1512 		ip_input_multicast_v6(ire, mp, ip6h, ira);
1513 		return;
1514 	}
1515 	ip_fanout_v6(mp, ip6h, ira);
1516 }
1517 
1518 /*
1519  * Handle multiple zones which want to receive the same multicast packets
1520  * on this ill by delivering a packet to each of them.
1521  *
1522  * Note that for packets delivered to transports we could instead do this
1523  * as part of the fanout code, but since we need to handle icmp_inbound
1524  * it is simpler to have multicast work the same as IPv4 broadcast.
1525  *
1526  * The ip_fanout matching for multicast matches based on ilm independent of
1527  * zoneid since the zoneid restriction is applied when joining a multicast
1528  * group.
1529  */
1530 /* ARGSUSED */
1531 static void
1532 ip_input_multicast_v6(ire_t *ire, mblk_t *mp, ip6_t *ip6h, ip_recv_attr_t *ira)
1533 {
1534 	ill_t		*ill = ira->ira_ill;
1535 	iaflags_t	iraflags = ira->ira_flags;
1536 	ip_stack_t	*ipst = ill->ill_ipst;
1537 	netstack_t	*ns = ipst->ips_netstack;
1538 	zoneid_t	zoneid;
1539 	mblk_t		*mp1;
1540 	ip6_t		*ip6h1;
1541 	uint_t		ira_pktlen = ira->ira_pktlen;
1542 	uint16_t	ira_ip_hdr_length = ira->ira_ip_hdr_length;
1543 
1544 	/* ire_recv_multicast has switched to the upper ill for IPMP */
1545 	ASSERT(!IS_UNDER_IPMP(ill));
1546 
1547 	/*
1548 	 * If we don't have more than one shared-IP zone, or if
1549 	 * there are no members in anything but the global zone,
1550 	 * then just set the zoneid and proceed.
1551 	 */
1552 	if (ns->netstack_numzones == 1 ||
1553 	    !ill_hasmembers_otherzones_v6(ill, &ip6h->ip6_dst,
1554 	    GLOBAL_ZONEID)) {
1555 		ira->ira_zoneid = GLOBAL_ZONEID;
1556 
1557 		/* If sender didn't want this zone to receive it, drop */
1558 		if ((iraflags & IRAF_NO_LOOP_ZONEID_SET) &&
1559 		    ira->ira_no_loop_zoneid == ira->ira_zoneid) {
1560 			ip_drop_input("Multicast but wrong zoneid", mp, ill);
1561 			freemsg(mp);
1562 			return;
1563 		}
1564 		ip_fanout_v6(mp, ip6h, ira);
1565 		return;
1566 	}
1567 
1568 	/*
1569 	 * Here we loop over all zoneids that have members in the group
1570 	 * and deliver a packet to ip_fanout for each zoneid.
1571 	 *
1572 	 * First find any members in the lowest numeric zoneid by looking for
1573 	 * first zoneid larger than -1 (ALL_ZONES).
1574 	 * We terminate the loop when we receive -1 (ALL_ZONES).
1575 	 */
1576 	zoneid = ill_hasmembers_nextzone_v6(ill, &ip6h->ip6_dst, ALL_ZONES);
1577 	for (; zoneid != ALL_ZONES;
1578 	    zoneid = ill_hasmembers_nextzone_v6(ill, &ip6h->ip6_dst, zoneid)) {
1579 		/*
1580 		 * Avoid an extra copymsg/freemsg by skipping global zone here
1581 		 * and doing that at the end.
1582 		 */
1583 		if (zoneid == GLOBAL_ZONEID)
1584 			continue;
1585 
1586 		ira->ira_zoneid = zoneid;
1587 
1588 		/* If sender didn't want this zone to receive it, skip */
1589 		if ((iraflags & IRAF_NO_LOOP_ZONEID_SET) &&
1590 		    ira->ira_no_loop_zoneid == ira->ira_zoneid)
1591 			continue;
1592 
1593 		mp1 = copymsg(mp);
1594 		if (mp1 == NULL) {
1595 			/* Failed to deliver to one zone */
1596 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsInDiscards);
1597 			ip_drop_input("ipIfStatsInDiscards", mp, ill);
1598 			continue;
1599 		}
1600 		ip6h1 = (ip6_t *)mp1->b_rptr;
1601 		ip_fanout_v6(mp1, ip6h1, ira);
1602 		/*
1603 		 * IPsec might have modified ira_pktlen and ira_ip_hdr_length
1604 		 * so we restore them for a potential next iteration
1605 		 */
1606 		ira->ira_pktlen = ira_pktlen;
1607 		ira->ira_ip_hdr_length = ira_ip_hdr_length;
1608 	}
1609 
1610 	/* Do the main ire */
1611 	ira->ira_zoneid = GLOBAL_ZONEID;
1612 	/* If sender didn't want this zone to receive it, drop */
1613 	if ((iraflags & IRAF_NO_LOOP_ZONEID_SET) &&
1614 	    ira->ira_no_loop_zoneid == ira->ira_zoneid) {
1615 		ip_drop_input("Multicast but wrong zoneid", mp, ill);
1616 		freemsg(mp);
1617 	} else {
1618 		ip_fanout_v6(mp, ip6h, ira);
1619 	}
1620 }
1621 
1622 
1623 /*
1624  * Determine the zoneid and IRAF_TX_MAC_EXEMPTABLE if trusted extensions
1625  * is in use. Updates ira_zoneid and ira_flags as a result.
1626  */
1627 static void
1628 ip_fanout_tx_v6(mblk_t *mp, ip6_t *ip6h, uint8_t protocol, uint_t ip_hdr_length,
1629     ip_recv_attr_t *ira)
1630 {
1631 	uint16_t	*up;
1632 	uint16_t	lport;
1633 	zoneid_t	zoneid;
1634 
1635 	ASSERT(ira->ira_flags & IRAF_SYSTEM_LABELED);
1636 
1637 	/*
1638 	 * If the packet is unlabeled we might allow read-down
1639 	 * for MAC_EXEMPT. Below we clear this if it is a multi-level
1640 	 * port (MLP).
1641 	 * Note that ira_tsl can be NULL here.
1642 	 */
1643 	if (ira->ira_tsl != NULL && ira->ira_tsl->tsl_flags & TSLF_UNLABELED)
1644 		ira->ira_flags |= IRAF_TX_MAC_EXEMPTABLE;
1645 
1646 	if (ira->ira_zoneid != ALL_ZONES)
1647 		return;
1648 
1649 	ira->ira_flags |= IRAF_TX_SHARED_ADDR;
1650 
1651 	up = (uint16_t *)((uchar_t *)ip6h + ip_hdr_length);
1652 	switch (protocol) {
1653 	case IPPROTO_TCP:
1654 	case IPPROTO_SCTP:
1655 	case IPPROTO_UDP:
1656 		/* Caller ensures this */
1657 		ASSERT(((uchar_t *)ip6h) + ip_hdr_length +4 <= mp->b_wptr);
1658 
1659 		/*
1660 		 * Only these transports support MLP.
1661 		 * We know their destination port numbers is in
1662 		 * the same place in the header.
1663 		 */
1664 		lport = up[1];
1665 
1666 		/*
1667 		 * No need to handle exclusive-stack zones
1668 		 * since ALL_ZONES only applies to the shared IP instance.
1669 		 */
1670 		zoneid = tsol_mlp_findzone(protocol, lport);
1671 		/*
1672 		 * If no shared MLP is found, tsol_mlp_findzone returns
1673 		 * ALL_ZONES.  In that case, we assume it's SLP, and
1674 		 * search for the zone based on the packet label.
1675 		 *
1676 		 * If there is such a zone, we prefer to find a
1677 		 * connection in it.  Otherwise, we look for a
1678 		 * MAC-exempt connection in any zone whose label
1679 		 * dominates the default label on the packet.
1680 		 */
1681 		if (zoneid == ALL_ZONES)
1682 			zoneid = tsol_attr_to_zoneid(ira);
1683 		else
1684 			ira->ira_flags &= ~IRAF_TX_MAC_EXEMPTABLE;
1685 		break;
1686 	default:
1687 		/* Handle shared address for other protocols */
1688 		zoneid = tsol_attr_to_zoneid(ira);
1689 		break;
1690 	}
1691 	ira->ira_zoneid = zoneid;
1692 }
1693 
1694 /*
1695  * Increment checksum failure statistics
1696  */
1697 static void
1698 ip_input_cksum_err_v6(uint8_t protocol, uint16_t hck_flags, ill_t *ill)
1699 {
1700 	ip_stack_t	*ipst = ill->ill_ipst;
1701 
1702 	switch (protocol) {
1703 	case IPPROTO_TCP:
1704 		BUMP_MIB(ill->ill_ip_mib, tcpIfStatsInErrs);
1705 
1706 		if (hck_flags & HCK_FULLCKSUM)
1707 			IP6_STAT(ipst, ip6_tcp_in_full_hw_cksum_err);
1708 		else if (hck_flags & HCK_PARTIALCKSUM)
1709 			IP6_STAT(ipst, ip6_tcp_in_part_hw_cksum_err);
1710 		else
1711 			IP6_STAT(ipst, ip6_tcp_in_sw_cksum_err);
1712 		break;
1713 	case IPPROTO_UDP:
1714 		BUMP_MIB(ill->ill_ip_mib, udpIfStatsInCksumErrs);
1715 		if (hck_flags & HCK_FULLCKSUM)
1716 			IP6_STAT(ipst, ip6_udp_in_full_hw_cksum_err);
1717 		else if (hck_flags & HCK_PARTIALCKSUM)
1718 			IP6_STAT(ipst, ip6_udp_in_part_hw_cksum_err);
1719 		else
1720 			IP6_STAT(ipst, ip6_udp_in_sw_cksum_err);
1721 		break;
1722 	case IPPROTO_ICMPV6:
1723 		BUMP_MIB(ill->ill_icmp6_mib, ipv6IfIcmpInMsgs);
1724 		BUMP_MIB(ill->ill_icmp6_mib, ipv6IfIcmpInErrors);
1725 		break;
1726 	default:
1727 		ASSERT(0);
1728 		break;
1729 	}
1730 }
1731 
1732 /* Calculate the IPv6 pseudo-header checksum for TCP, UDP, and ICMPV6 */
1733 uint32_t
1734 ip_input_cksum_pseudo_v6(ip6_t *ip6h, ip_recv_attr_t *ira)
1735 {
1736 	uint_t		ulp_len;
1737 	uint32_t	cksum;
1738 	uint8_t		protocol = ira->ira_protocol;
1739 	uint16_t	ip_hdr_length = ira->ira_ip_hdr_length;
1740 
1741 #define	iphs    ((uint16_t *)ip6h)
1742 
1743 	switch (protocol) {
1744 	case IPPROTO_TCP:
1745 		ulp_len = ira->ira_pktlen - ip_hdr_length;
1746 
1747 		/* Protocol and length */
1748 		cksum = htons(ulp_len) + IP_TCP_CSUM_COMP;
1749 		/* IP addresses */
1750 		cksum += iphs[4] + iphs[5] + iphs[6] + iphs[7] +
1751 		    iphs[8] + iphs[9] + iphs[10] + iphs[11] +
1752 		    iphs[12] + iphs[13] + iphs[14] + iphs[15] +
1753 		    iphs[16] + iphs[17] + iphs[18] + iphs[19];
1754 		break;
1755 
1756 	case IPPROTO_UDP: {
1757 		udpha_t		*udpha;
1758 
1759 		udpha = (udpha_t  *)((uchar_t *)ip6h + ip_hdr_length);
1760 
1761 		/* Protocol and length */
1762 		cksum = udpha->uha_length + IP_UDP_CSUM_COMP;
1763 		/* IP addresses */
1764 		cksum += iphs[4] + iphs[5] + iphs[6] + iphs[7] +
1765 		    iphs[8] + iphs[9] + iphs[10] + iphs[11] +
1766 		    iphs[12] + iphs[13] + iphs[14] + iphs[15] +
1767 		    iphs[16] + iphs[17] + iphs[18] + iphs[19];
1768 		break;
1769 	}
1770 	case IPPROTO_ICMPV6:
1771 		ulp_len = ira->ira_pktlen - ip_hdr_length;
1772 
1773 		/* Protocol and length */
1774 		cksum = htons(ulp_len) + IP_ICMPV6_CSUM_COMP;
1775 		/* IP addresses */
1776 		cksum += iphs[4] + iphs[5] + iphs[6] + iphs[7] +
1777 		    iphs[8] + iphs[9] + iphs[10] + iphs[11] +
1778 		    iphs[12] + iphs[13] + iphs[14] + iphs[15] +
1779 		    iphs[16] + iphs[17] + iphs[18] + iphs[19];
1780 		break;
1781 	default:
1782 		cksum = 0;
1783 		break;
1784 	}
1785 #undef	iphs
1786 	return (cksum);
1787 }
1788 
1789 
1790 /*
1791  * Software verification of the ULP checksums.
1792  * Returns B_TRUE if ok.
1793  * Increments statistics of failed.
1794  */
1795 static boolean_t
1796 ip_input_sw_cksum_v6(mblk_t *mp, ip6_t *ip6h, ip_recv_attr_t *ira)
1797 {
1798 	ip_stack_t	*ipst = ira->ira_ill->ill_ipst;
1799 	uint32_t	cksum;
1800 	uint8_t		protocol = ira->ira_protocol;
1801 	uint16_t	ip_hdr_length = ira->ira_ip_hdr_length;
1802 
1803 	IP6_STAT(ipst, ip6_in_sw_cksum);
1804 
1805 	ASSERT(protocol == IPPROTO_TCP || protocol == IPPROTO_UDP ||
1806 	    protocol == IPPROTO_ICMPV6);
1807 
1808 	cksum = ip_input_cksum_pseudo_v6(ip6h, ira);
1809 	cksum = IP_CSUM(mp, ip_hdr_length, cksum);
1810 	if (cksum == 0)
1811 		return (B_TRUE);
1812 
1813 	ip_input_cksum_err_v6(protocol, 0, ira->ira_ill);
1814 	return (B_FALSE);
1815 }
1816 
1817 /*
1818  * Verify the ULP checksums.
1819  * Returns B_TRUE if ok, or if the ULP doesn't have a well-defined checksum
1820  * algorithm.
1821  * Increments statistics if failed.
1822  */
1823 static boolean_t
1824 ip_input_cksum_v6(iaflags_t iraflags, mblk_t *mp, ip6_t *ip6h,
1825     ip_recv_attr_t *ira)
1826 {
1827 	ill_t		*ill = ira->ira_rill;
1828 	uint16_t	hck_flags;
1829 	uint32_t	cksum;
1830 	mblk_t		*mp1;
1831 	uint_t		len;
1832 	uint8_t		protocol = ira->ira_protocol;
1833 	uint16_t	ip_hdr_length = ira->ira_ip_hdr_length;
1834 
1835 
1836 	switch (protocol) {
1837 	case IPPROTO_TCP:
1838 	case IPPROTO_ICMPV6:
1839 		break;
1840 
1841 	case IPPROTO_UDP: {
1842 		udpha_t		*udpha;
1843 
1844 		udpha = (udpha_t  *)((uchar_t *)ip6h + ip_hdr_length);
1845 		/*
1846 		 *  Before going through the regular checksum
1847 		 *  calculation, make sure the received checksum
1848 		 *  is non-zero. RFC 2460 says, a 0x0000 checksum
1849 		 *  in a UDP packet (within IPv6 packet) is invalid
1850 		 *  and should be replaced by 0xffff. This makes
1851 		 *  sense as regular checksum calculation will
1852 		 *  pass for both the cases i.e. 0x0000 and 0xffff.
1853 		 *  Removing one of the case makes error detection
1854 		 *  stronger.
1855 		 */
1856 		if (udpha->uha_checksum == 0) {
1857 			/* 0x0000 checksum is invalid */
1858 			BUMP_MIB(ill->ill_ip_mib, udpIfStatsInCksumErrs);
1859 			return (B_FALSE);
1860 		}
1861 		break;
1862 	}
1863 	case IPPROTO_SCTP: {
1864 		sctp_hdr_t	*sctph;
1865 		uint32_t	pktsum;
1866 
1867 		sctph = (sctp_hdr_t *)((uchar_t *)ip6h + ip_hdr_length);
1868 #ifdef	DEBUG
1869 		if (skip_sctp_cksum)
1870 			return (B_TRUE);
1871 #endif
1872 		pktsum = sctph->sh_chksum;
1873 		sctph->sh_chksum = 0;
1874 		cksum = sctp_cksum(mp, ip_hdr_length);
1875 		sctph->sh_chksum = pktsum;
1876 		if (cksum == pktsum)
1877 			return (B_TRUE);
1878 
1879 		/*
1880 		 * Defer until later whether a bad checksum is ok
1881 		 * in order to allow RAW sockets to use Adler checksum
1882 		 * with SCTP.
1883 		 */
1884 		ira->ira_flags |= IRAF_SCTP_CSUM_ERR;
1885 		return (B_TRUE);
1886 	}
1887 
1888 	default:
1889 		/* No ULP checksum to verify. */
1890 		return (B_TRUE);
1891 	}
1892 
1893 	/*
1894 	 * Revert to software checksum calculation if the interface
1895 	 * isn't capable of checksum offload.
1896 	 * We clear DB_CKSUMFLAGS when going through IPsec in ip_fanout.
1897 	 * Note: IRAF_NO_HW_CKSUM is not currently used.
1898 	 */
1899 	ASSERT(!IS_IPMP(ill));
1900 	if ((iraflags & IRAF_NO_HW_CKSUM) || !ILL_HCKSUM_CAPABLE(ill) ||
1901 	    !dohwcksum) {
1902 		return (ip_input_sw_cksum_v6(mp, ip6h, ira));
1903 	}
1904 
1905 	/*
1906 	 * We apply this for all ULP protocols. Does the HW know to
1907 	 * not set the flags for SCTP and other protocols.
1908 	 */
1909 
1910 	hck_flags = DB_CKSUMFLAGS(mp);
1911 
1912 	if (hck_flags & HCK_FULLCKSUM_OK) {
1913 		/*
1914 		 * Hardware has already verified the checksum.
1915 		 */
1916 		return (B_TRUE);
1917 	}
1918 
1919 	if (hck_flags & HCK_FULLCKSUM) {
1920 		/*
1921 		 * Full checksum has been computed by the hardware
1922 		 * and has been attached.  If the driver wants us to
1923 		 * verify the correctness of the attached value, in
1924 		 * order to protect against faulty hardware, compare
1925 		 * it against -0 (0xFFFF) to see if it's valid.
1926 		 */
1927 		cksum = DB_CKSUM16(mp);
1928 		if (cksum == 0xFFFF)
1929 			return (B_TRUE);
1930 		ip_input_cksum_err_v6(protocol, hck_flags, ira->ira_ill);
1931 		return (B_FALSE);
1932 	}
1933 
1934 	mp1 = mp->b_cont;
1935 	if ((hck_flags & HCK_PARTIALCKSUM) &&
1936 	    (mp1 == NULL || mp1->b_cont == NULL) &&
1937 	    ip_hdr_length >= DB_CKSUMSTART(mp) &&
1938 	    ((len = ip_hdr_length - DB_CKSUMSTART(mp)) & 1) == 0) {
1939 		uint32_t	adj;
1940 		uchar_t		*cksum_start;
1941 
1942 		cksum = ip_input_cksum_pseudo_v6(ip6h, ira);
1943 
1944 		cksum_start = ((uchar_t *)ip6h + DB_CKSUMSTART(mp));
1945 
1946 		/*
1947 		 * Partial checksum has been calculated by hardware
1948 		 * and attached to the packet; in addition, any
1949 		 * prepended extraneous data is even byte aligned,
1950 		 * and there are at most two mblks associated with
1951 		 * the packet.  If any such data exists, we adjust
1952 		 * the checksum; also take care any postpended data.
1953 		 */
1954 		IP_ADJCKSUM_PARTIAL(cksum_start, mp, mp1, len, adj);
1955 		/*
1956 		 * One's complement subtract extraneous checksum
1957 		 */
1958 		cksum += DB_CKSUM16(mp);
1959 		if (adj >= cksum)
1960 			cksum = ~(adj - cksum) & 0xFFFF;
1961 		else
1962 			cksum -= adj;
1963 		cksum = (cksum & 0xFFFF) + ((int)cksum >> 16);
1964 		cksum = (cksum & 0xFFFF) + ((int)cksum >> 16);
1965 		if (!(~cksum & 0xFFFF))
1966 			return (B_TRUE);
1967 
1968 		ip_input_cksum_err_v6(protocol, hck_flags, ira->ira_ill);
1969 		return (B_FALSE);
1970 	}
1971 	return (ip_input_sw_cksum_v6(mp, ip6h, ira));
1972 }
1973 
1974 
1975 /*
1976  * Handle fanout of received packets.
1977  * Unicast packets that are looped back (from ire_send_local_v6) and packets
1978  * from the wire are differentiated by checking IRAF_VERIFY_ULP_CKSUM.
1979  *
1980  * IPQoS Notes
1981  * Before sending it to the client, invoke IPPF processing. Policy processing
1982  * takes place only if the callout_position, IPP_LOCAL_IN, is enabled.
1983  */
1984 void
1985 ip_fanout_v6(mblk_t *mp, ip6_t *ip6h, ip_recv_attr_t *ira)
1986 {
1987 	ill_t		*ill = ira->ira_ill;
1988 	iaflags_t	iraflags = ira->ira_flags;
1989 	ip_stack_t	*ipst = ill->ill_ipst;
1990 	uint8_t		protocol;
1991 	conn_t		*connp;
1992 #define	rptr	((uchar_t *)ip6h)
1993 	uint_t		ip_hdr_length;
1994 	uint_t		min_ulp_header_length;
1995 	int		offset;
1996 	ssize_t		len;
1997 	netstack_t	*ns = ipst->ips_netstack;
1998 	ipsec_stack_t	*ipss = ns->netstack_ipsec;
1999 	ill_t		*rill = ira->ira_rill;
2000 
2001 	ASSERT(ira->ira_pktlen == ntohs(ip6h->ip6_plen) + IPV6_HDR_LEN);
2002 
2003 	/*
2004 	 * We repeat this as we parse over destination options header and
2005 	 * fragment headers (earlier we've handled any hop-by-hop options
2006 	 * header.)
2007 	 * We update ira_protocol and ira_ip_hdr_length as we skip past
2008 	 * the intermediate headers; they already point past any
2009 	 * hop-by-hop header.
2010 	 */
2011 repeat:
2012 	protocol = ira->ira_protocol;
2013 	ip_hdr_length = ira->ira_ip_hdr_length;
2014 
2015 	/*
2016 	 * Time for IPP once we've done reassembly and IPsec.
2017 	 * We skip this for loopback packets since we don't do IPQoS
2018 	 * on loopback.
2019 	 */
2020 	if (IPP_ENABLED(IPP_LOCAL_IN, ipst) &&
2021 	    !(iraflags & IRAF_LOOPBACK) &&
2022 	    (protocol != IPPROTO_ESP || protocol != IPPROTO_AH ||
2023 	    protocol != IPPROTO_DSTOPTS || protocol != IPPROTO_ROUTING ||
2024 	    protocol != IPPROTO_FRAGMENT)) {
2025 		/*
2026 		 * Use the interface on which the packet arrived - not where
2027 		 * the IP address is hosted.
2028 		 */
2029 		/* ip_process translates an IS_UNDER_IPMP */
2030 		mp = ip_process(IPP_LOCAL_IN, mp, rill, ill);
2031 		if (mp == NULL) {
2032 			/* ip_drop_packet and MIB done */
2033 			return;
2034 		}
2035 	}
2036 
2037 	/* Determine the minimum required size of the upper-layer header */
2038 	/* Need to do this for at least the set of ULPs that TX handles. */
2039 	switch (protocol) {
2040 	case IPPROTO_TCP:
2041 		min_ulp_header_length = TCP_MIN_HEADER_LENGTH;
2042 		break;
2043 	case IPPROTO_SCTP:
2044 		min_ulp_header_length = SCTP_COMMON_HDR_LENGTH;
2045 		break;
2046 	case IPPROTO_UDP:
2047 		min_ulp_header_length = UDPH_SIZE;
2048 		break;
2049 	case IPPROTO_ICMP:
2050 	case IPPROTO_ICMPV6:
2051 		min_ulp_header_length = ICMPH_SIZE;
2052 		break;
2053 	case IPPROTO_FRAGMENT:
2054 	case IPPROTO_DSTOPTS:
2055 	case IPPROTO_ROUTING:
2056 		min_ulp_header_length = MIN_EHDR_LEN;
2057 		break;
2058 	default:
2059 		min_ulp_header_length = 0;
2060 		break;
2061 	}
2062 	/* Make sure we have the min ULP header length */
2063 	len = mp->b_wptr - rptr;
2064 	if (len < ip_hdr_length + min_ulp_header_length) {
2065 		if (ira->ira_pktlen < ip_hdr_length + min_ulp_header_length)
2066 			goto pkt_too_short;
2067 
2068 		IP6_STAT(ipst, ip6_recv_pullup);
2069 		ip6h = ip_pullup(mp, ip_hdr_length + min_ulp_header_length,
2070 		    ira);
2071 		if (ip6h == NULL)
2072 			goto discard;
2073 		len = mp->b_wptr - rptr;
2074 	}
2075 
2076 	/*
2077 	 * If trusted extensions then determine the zoneid and TX specific
2078 	 * ira_flags.
2079 	 */
2080 	if (iraflags & IRAF_SYSTEM_LABELED) {
2081 		/* This can update ira->ira_flags and ira->ira_zoneid */
2082 		ip_fanout_tx_v6(mp, ip6h, protocol, ip_hdr_length, ira);
2083 		iraflags = ira->ira_flags;
2084 	}
2085 
2086 
2087 	/* Verify ULP checksum. Handles TCP, UDP, and SCTP */
2088 	if (iraflags & IRAF_VERIFY_ULP_CKSUM) {
2089 		if (!ip_input_cksum_v6(iraflags, mp, ip6h, ira)) {
2090 			/* Bad checksum. Stats are already incremented */
2091 			ip_drop_input("Bad ULP checksum", mp, ill);
2092 			freemsg(mp);
2093 			return;
2094 		}
2095 		/* IRAF_SCTP_CSUM_ERR could have been set */
2096 		iraflags = ira->ira_flags;
2097 	}
2098 	switch (protocol) {
2099 	case IPPROTO_TCP:
2100 		/* For TCP, discard multicast packets. */
2101 		if (iraflags & IRAF_MULTIBROADCAST)
2102 			goto discard;
2103 
2104 		/* First mblk contains IP+TCP headers per above check */
2105 		ASSERT(len >= ip_hdr_length + TCP_MIN_HEADER_LENGTH);
2106 
2107 		/* TCP options present? */
2108 		offset = ((uchar_t *)ip6h)[ip_hdr_length + 12] >> 4;
2109 		if (offset != 5) {
2110 			if (offset < 5)
2111 				goto discard;
2112 
2113 			/*
2114 			 * There must be TCP options.
2115 			 * Make sure we can grab them.
2116 			 */
2117 			offset <<= 2;
2118 			offset += ip_hdr_length;
2119 			if (len < offset) {
2120 				if (ira->ira_pktlen < offset)
2121 					goto pkt_too_short;
2122 
2123 				IP6_STAT(ipst, ip6_recv_pullup);
2124 				ip6h = ip_pullup(mp, offset, ira);
2125 				if (ip6h == NULL)
2126 					goto discard;
2127 				len = mp->b_wptr - rptr;
2128 			}
2129 		}
2130 
2131 		/*
2132 		 * Pass up a squeue hint to tcp.
2133 		 * If ira_sqp is already set (this is loopback) we leave it
2134 		 * alone.
2135 		 */
2136 		if (ira->ira_sqp == NULL) {
2137 			ira->ira_sqp = ip_squeue_get(ira->ira_ring);
2138 		}
2139 
2140 		/* Look for AF_INET or AF_INET6 that matches */
2141 		connp = ipcl_classify_v6(mp, IPPROTO_TCP, ip_hdr_length,
2142 		    ira, ipst);
2143 		if (connp == NULL) {
2144 			/* Send the TH_RST */
2145 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsHCInDelivers);
2146 			tcp_xmit_listeners_reset(mp, ira, ipst, NULL);
2147 			return;
2148 		}
2149 		if (connp->conn_incoming_ifindex != 0 &&
2150 		    connp->conn_incoming_ifindex != ira->ira_ruifindex) {
2151 			CONN_DEC_REF(connp);
2152 
2153 			/* Send the TH_RST */
2154 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsHCInDelivers);
2155 			tcp_xmit_listeners_reset(mp, ira, ipst, NULL);
2156 			return;
2157 		}
2158 		if (CONN_INBOUND_POLICY_PRESENT_V6(connp, ipss) ||
2159 		    (iraflags & IRAF_IPSEC_SECURE)) {
2160 			mp = ipsec_check_inbound_policy(mp, connp,
2161 			    NULL, ip6h, ira);
2162 			if (mp == NULL) {
2163 				BUMP_MIB(ill->ill_ip_mib, ipIfStatsInDiscards);
2164 				/* Note that mp is NULL */
2165 				ip_drop_input("ipIfStatsInDiscards", mp, ill);
2166 				CONN_DEC_REF(connp);
2167 				return;
2168 			}
2169 		}
2170 		/* Found a client; up it goes */
2171 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsHCInDelivers);
2172 		ira->ira_ill = ira->ira_rill = NULL;
2173 		if (!IPCL_IS_TCP(connp)) {
2174 			/* Not TCP; must be SOCK_RAW, IPPROTO_TCP */
2175 			(connp->conn_recv)(connp, mp, NULL, ira);
2176 			CONN_DEC_REF(connp);
2177 			ira->ira_ill = ill;
2178 			ira->ira_rill = rill;
2179 			return;
2180 		}
2181 
2182 		/*
2183 		 * We do different processing whether called from
2184 		 * ip_accept_tcp and we match the target, don't match
2185 		 * the target, and when we are called by ip_input.
2186 		 */
2187 		if (iraflags & IRAF_TARGET_SQP) {
2188 			if (ira->ira_target_sqp == connp->conn_sqp) {
2189 				mblk_t	*attrmp;
2190 
2191 				attrmp = ip_recv_attr_to_mblk(ira);
2192 				if (attrmp == NULL) {
2193 					BUMP_MIB(ill->ill_ip_mib,
2194 					    ipIfStatsInDiscards);
2195 					ip_drop_input("ipIfStatsInDiscards",
2196 					    mp, ill);
2197 					freemsg(mp);
2198 					CONN_DEC_REF(connp);
2199 				} else {
2200 					SET_SQUEUE(attrmp, connp->conn_recv,
2201 					    connp);
2202 					attrmp->b_cont = mp;
2203 					ASSERT(ira->ira_target_sqp_mp == NULL);
2204 					ira->ira_target_sqp_mp = attrmp;
2205 					/*
2206 					 * Conn ref release when drained from
2207 					 * the squeue.
2208 					 */
2209 				}
2210 			} else {
2211 				SQUEUE_ENTER_ONE(connp->conn_sqp, mp,
2212 				    connp->conn_recv, connp, ira, SQ_FILL,
2213 				    SQTAG_IP6_TCP_INPUT);
2214 			}
2215 		} else {
2216 			SQUEUE_ENTER_ONE(connp->conn_sqp, mp, connp->conn_recv,
2217 			    connp, ira, ip_squeue_flag, SQTAG_IP6_TCP_INPUT);
2218 		}
2219 		ira->ira_ill = ill;
2220 		ira->ira_rill = rill;
2221 		return;
2222 
2223 	case IPPROTO_SCTP: {
2224 		sctp_hdr_t	*sctph;
2225 		uint32_t	ports;	/* Source and destination ports */
2226 		sctp_stack_t	*sctps = ipst->ips_netstack->netstack_sctp;
2227 
2228 		/* For SCTP, discard multicast packets. */
2229 		if (iraflags & IRAF_MULTIBROADCAST)
2230 			goto discard;
2231 
2232 		/*
2233 		 * Since there is no SCTP h/w cksum support yet, just
2234 		 * clear the flag.
2235 		 */
2236 		DB_CKSUMFLAGS(mp) = 0;
2237 
2238 		/* Length ensured above */
2239 		ASSERT(MBLKL(mp) >= ip_hdr_length + SCTP_COMMON_HDR_LENGTH);
2240 		sctph = (sctp_hdr_t *)(rptr + ip_hdr_length);
2241 
2242 		/* get the ports */
2243 		ports = *(uint32_t *)&sctph->sh_sport;
2244 
2245 		if (iraflags & IRAF_SCTP_CSUM_ERR) {
2246 			/*
2247 			 * No potential sctp checksum errors go to the Sun
2248 			 * sctp stack however they might be Adler-32 summed
2249 			 * packets a userland stack bound to a raw IP socket
2250 			 * could reasonably use. Note though that Adler-32 is
2251 			 * a long deprecated algorithm and customer sctp
2252 			 * networks should eventually migrate to CRC-32 at
2253 			 * which time this facility should be removed.
2254 			 */
2255 			ip_fanout_sctp_raw(mp, NULL, ip6h, ports, ira);
2256 			return;
2257 		}
2258 		connp = sctp_fanout(&ip6h->ip6_src, &ip6h->ip6_dst, ports,
2259 		    ira, mp, sctps, sctph);
2260 		if (connp == NULL) {
2261 			/* Check for raw socket or OOTB handling */
2262 			ip_fanout_sctp_raw(mp, NULL, ip6h, ports, ira);
2263 			return;
2264 		}
2265 		if (connp->conn_incoming_ifindex != 0 &&
2266 		    connp->conn_incoming_ifindex != ira->ira_ruifindex) {
2267 			CONN_DEC_REF(connp);
2268 
2269 			/* Check for raw socket or OOTB handling */
2270 			ip_fanout_sctp_raw(mp, NULL, ip6h, ports, ira);
2271 			return;
2272 		}
2273 
2274 		/* Found a client; up it goes */
2275 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsHCInDelivers);
2276 		sctp_input(connp, NULL, ip6h, mp, ira);
2277 		/* sctp_input does a rele of the sctp_t */
2278 		return;
2279 	}
2280 
2281 	case IPPROTO_UDP:
2282 		/* First mblk contains IP+UDP headers as checked above */
2283 		ASSERT(MBLKL(mp) >= ip_hdr_length + UDPH_SIZE);
2284 
2285 		if (iraflags & IRAF_MULTIBROADCAST) {
2286 			uint16_t *up;	/* Pointer to ports in ULP header */
2287 
2288 			up = (uint16_t *)((uchar_t *)ip6h + ip_hdr_length);
2289 
2290 			ip_fanout_udp_multi_v6(mp, ip6h, up[1], up[0], ira);
2291 			return;
2292 		}
2293 
2294 		/* Look for AF_INET or AF_INET6 that matches */
2295 		connp = ipcl_classify_v6(mp, IPPROTO_UDP, ip_hdr_length,
2296 		    ira, ipst);
2297 		if (connp == NULL) {
2298 	no_udp_match:
2299 			if (ipst->ips_ipcl_proto_fanout_v6[IPPROTO_UDP].
2300 			    connf_head != NULL) {
2301 				ASSERT(ira->ira_protocol == IPPROTO_UDP);
2302 				ip_fanout_proto_v6(mp, ip6h, ira);
2303 			} else {
2304 				ip_fanout_send_icmp_v6(mp, ICMP6_DST_UNREACH,
2305 				    ICMP6_DST_UNREACH_NOPORT, ira);
2306 			}
2307 			return;
2308 
2309 		}
2310 		if (connp->conn_incoming_ifindex != 0 &&
2311 		    connp->conn_incoming_ifindex != ira->ira_ruifindex) {
2312 			CONN_DEC_REF(connp);
2313 			goto no_udp_match;
2314 		}
2315 		if (IPCL_IS_NONSTR(connp) ? connp->conn_flow_cntrld :
2316 		    !canputnext(connp->conn_rq)) {
2317 			CONN_DEC_REF(connp);
2318 			BUMP_MIB(ill->ill_ip_mib, udpIfStatsInOverflows);
2319 			ip_drop_input("udpIfStatsInOverflows", mp, ill);
2320 			freemsg(mp);
2321 			return;
2322 		}
2323 		if (CONN_INBOUND_POLICY_PRESENT_V6(connp, ipss) ||
2324 		    (iraflags & IRAF_IPSEC_SECURE)) {
2325 			mp = ipsec_check_inbound_policy(mp, connp,
2326 			    NULL, ip6h, ira);
2327 			if (mp == NULL) {
2328 				BUMP_MIB(ill->ill_ip_mib, ipIfStatsInDiscards);
2329 				/* Note that mp is NULL */
2330 				ip_drop_input("ipIfStatsInDiscards", mp, ill);
2331 				CONN_DEC_REF(connp);
2332 				return;
2333 			}
2334 		}
2335 
2336 		/* Found a client; up it goes */
2337 		IP6_STAT(ipst, ip6_udp_fannorm);
2338 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsHCInDelivers);
2339 		ira->ira_ill = ira->ira_rill = NULL;
2340 		(connp->conn_recv)(connp, mp, NULL, ira);
2341 		CONN_DEC_REF(connp);
2342 		ira->ira_ill = ill;
2343 		ira->ira_rill = rill;
2344 		return;
2345 	default:
2346 		break;
2347 	}
2348 
2349 	/*
2350 	 * Clear hardware checksumming flag as it is currently only
2351 	 * used by TCP and UDP.
2352 	 */
2353 	DB_CKSUMFLAGS(mp) = 0;
2354 
2355 	switch (protocol) {
2356 	case IPPROTO_ICMPV6:
2357 		BUMP_MIB(ill->ill_icmp6_mib, ipv6IfIcmpInMsgs);
2358 
2359 		/* Check variable for testing applications */
2360 		if (ipst->ips_ipv6_drop_inbound_icmpv6) {
2361 			ip_drop_input("ipv6_drop_inbound_icmpv6", mp, ill);
2362 			freemsg(mp);
2363 			return;
2364 		}
2365 		/*
2366 		 * We need to accomodate icmp messages coming in clear
2367 		 * until we get everything secure from the wire. If
2368 		 * icmp_accept_clear_messages is zero we check with
2369 		 * the global policy and act accordingly. If it is
2370 		 * non-zero, we accept the message without any checks.
2371 		 * But *this does not mean* that this will be delivered
2372 		 * to RAW socket clients. By accepting we might send
2373 		 * replies back, change our MTU value etc.,
2374 		 * but delivery to the ULP/clients depends on their
2375 		 * policy dispositions.
2376 		 */
2377 		if (ipst->ips_icmp_accept_clear_messages == 0) {
2378 			mp = ipsec_check_global_policy(mp, NULL,
2379 			    NULL, ip6h, ira, ns);
2380 			if (mp == NULL)
2381 				return;
2382 		}
2383 
2384 		/*
2385 		 * On a labeled system, we have to check whether the zone
2386 		 * itself is permitted to receive raw traffic.
2387 		 */
2388 		if (ira->ira_flags & IRAF_SYSTEM_LABELED) {
2389 			if (!tsol_can_accept_raw(mp, ira, B_FALSE)) {
2390 				BUMP_MIB(ill->ill_icmp6_mib,
2391 				    ipv6IfIcmpInErrors);
2392 				ip_drop_input("tsol_can_accept_raw", mp, ill);
2393 				freemsg(mp);
2394 				return;
2395 			}
2396 		}
2397 
2398 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsHCInDelivers);
2399 		mp = icmp_inbound_v6(mp, ira);
2400 		if (mp == NULL) {
2401 			/* No need to pass to RAW sockets */
2402 			return;
2403 		}
2404 		break;
2405 
2406 	case IPPROTO_DSTOPTS: {
2407 		ip6_dest_t	*desthdr;
2408 		uint_t		ehdrlen;
2409 		uint8_t		*optptr;
2410 
2411 		/* We already check for MIN_EHDR_LEN above */
2412 
2413 		/* Check if AH is present and needs to be processed. */
2414 		mp = ipsec_early_ah_v6(mp, ira);
2415 		if (mp == NULL)
2416 			return;
2417 
2418 		/*
2419 		 * Reinitialize pointers, as ipsec_early_ah_v6() does
2420 		 * complete pullups.  We don't have to do more pullups
2421 		 * as a result.
2422 		 */
2423 		ip6h = (ip6_t *)mp->b_rptr;
2424 
2425 		if (ira->ira_pktlen - ip_hdr_length < MIN_EHDR_LEN)
2426 			goto pkt_too_short;
2427 
2428 		if (mp->b_cont != NULL &&
2429 		    rptr + ip_hdr_length + MIN_EHDR_LEN > mp->b_wptr) {
2430 			ip6h = ip_pullup(mp, ip_hdr_length + MIN_EHDR_LEN, ira);
2431 			if (ip6h == NULL)
2432 				goto discard;
2433 		}
2434 		desthdr = (ip6_dest_t *)(rptr + ip_hdr_length);
2435 		ehdrlen = 8 * (desthdr->ip6d_len + 1);
2436 		if (ira->ira_pktlen - ip_hdr_length < ehdrlen)
2437 			goto pkt_too_short;
2438 		if (mp->b_cont != NULL &&
2439 		    rptr + IPV6_HDR_LEN + ehdrlen > mp->b_wptr) {
2440 			ip6h = ip_pullup(mp, IPV6_HDR_LEN + ehdrlen, ira);
2441 			if (ip6h == NULL)
2442 				goto discard;
2443 
2444 			desthdr = (ip6_dest_t *)(rptr + ip_hdr_length);
2445 		}
2446 		optptr = (uint8_t *)&desthdr[1];
2447 
2448 		/*
2449 		 * Update ira_ip_hdr_length to skip the destination header
2450 		 * when we repeat.
2451 		 */
2452 		ira->ira_ip_hdr_length += ehdrlen;
2453 
2454 		ira->ira_protocol = desthdr->ip6d_nxt;
2455 
2456 		/*
2457 		 * Note: XXX This code does not seem to make
2458 		 * distinction between Destination Options Header
2459 		 * being before/after Routing Header which can
2460 		 * happen if we are at the end of source route.
2461 		 * This may become significant in future.
2462 		 * (No real significant Destination Options are
2463 		 * defined/implemented yet ).
2464 		 */
2465 		switch (ip_process_options_v6(mp, ip6h, optptr,
2466 		    ehdrlen - 2, IPPROTO_DSTOPTS, ira)) {
2467 		case -1:
2468 			/*
2469 			 * Packet has been consumed and any needed
2470 			 * ICMP errors sent.
2471 			 */
2472 			return;
2473 		case 0:
2474 			/* No action needed  continue */
2475 			break;
2476 		case 1:
2477 			/*
2478 			 * Unnexpected return value
2479 			 * (Router alert is a Hop-by-Hop option)
2480 			 */
2481 #ifdef DEBUG
2482 			panic("ip_fanout_v6: router "
2483 			    "alert hbh opt indication in dest opt");
2484 			/*NOTREACHED*/
2485 #else
2486 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsInDiscards);
2487 			ip_drop_input("ipIfStatsInDiscards", mp, ill);
2488 			freemsg(mp);
2489 			return;
2490 #endif
2491 		}
2492 		goto repeat;
2493 	}
2494 	case IPPROTO_FRAGMENT: {
2495 		ip6_frag_t *fraghdr;
2496 
2497 		if (ira->ira_pktlen - ip_hdr_length < sizeof (ip6_frag_t))
2498 			goto pkt_too_short;
2499 
2500 		if (mp->b_cont != NULL &&
2501 		    rptr + ip_hdr_length + sizeof (ip6_frag_t) > mp->b_wptr) {
2502 			ip6h = ip_pullup(mp,
2503 			    ip_hdr_length + sizeof (ip6_frag_t), ira);
2504 			if (ip6h == NULL)
2505 				goto discard;
2506 		}
2507 
2508 		fraghdr = (ip6_frag_t *)(rptr + ip_hdr_length);
2509 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsReasmReqds);
2510 
2511 		/*
2512 		 * Invoke the CGTP (multirouting) filtering module to
2513 		 * process the incoming packet. Packets identified as
2514 		 * duplicates must be discarded. Filtering is active
2515 		 * only if the ip_cgtp_filter ndd variable is
2516 		 * non-zero.
2517 		 */
2518 		if (ipst->ips_ip_cgtp_filter &&
2519 		    ipst->ips_ip_cgtp_filter_ops != NULL) {
2520 			int cgtp_flt_pkt;
2521 			netstackid_t stackid;
2522 
2523 			stackid = ipst->ips_netstack->netstack_stackid;
2524 
2525 			/*
2526 			 * CGTP and IPMP are mutually exclusive so
2527 			 * phyint_ifindex is fine here.
2528 			 */
2529 			cgtp_flt_pkt =
2530 			    ipst->ips_ip_cgtp_filter_ops->cfo_filter_v6(
2531 			    stackid, ill->ill_phyint->phyint_ifindex,
2532 			    ip6h, fraghdr);
2533 			if (cgtp_flt_pkt == CGTP_IP_PKT_DUPLICATE) {
2534 				ip_drop_input("CGTP_IP_PKT_DUPLICATE", mp, ill);
2535 				freemsg(mp);
2536 				return;
2537 			}
2538 		}
2539 
2540 		/*
2541 		 * Update ip_hdr_length to skip the frag header
2542 		 * ip_input_fragment_v6 will determine the extension header
2543 		 * prior to the fragment header and update its nexthdr value,
2544 		 * and also set ira_protocol to the nexthdr that follows the
2545 		 * completed fragment.
2546 		 */
2547 		ip_hdr_length += sizeof (ip6_frag_t);
2548 
2549 		/*
2550 		 * Make sure we have ira_l2src before we loose the original
2551 		 * mblk
2552 		 */
2553 		if (!(ira->ira_flags & IRAF_L2SRC_SET))
2554 			ip_setl2src(mp, ira, ira->ira_rill);
2555 
2556 		mp = ip_input_fragment_v6(mp, ip6h, fraghdr,
2557 		    ira->ira_pktlen - ip_hdr_length, ira);
2558 		if (mp == NULL) {
2559 			/* Reassembly is still pending */
2560 			return;
2561 		}
2562 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsReasmOKs);
2563 
2564 		/*
2565 		 * The mblk chain has the frag header removed and
2566 		 * ira_protocol, ira_pktlen, ira_ip_hdr_length as well as the
2567 		 * IP header has been updated to refleact the result.
2568 		 */
2569 		ip6h = (ip6_t *)mp->b_rptr;
2570 		ip_hdr_length = ira->ira_ip_hdr_length;
2571 		goto repeat;
2572 	}
2573 	case IPPROTO_HOPOPTS:
2574 		/*
2575 		 * Illegal header sequence.
2576 		 * (Hop-by-hop headers are processed above
2577 		 *  and required to immediately follow IPv6 header)
2578 		 */
2579 		ip_drop_input("ICMP_PARAM_PROBLEM", mp, ill);
2580 		icmp_param_problem_nexthdr_v6(mp, B_FALSE, ira);
2581 		return;
2582 
2583 	case IPPROTO_ROUTING: {
2584 		uint_t ehdrlen;
2585 		ip6_rthdr_t *rthdr;
2586 
2587 		/* Check if AH is present and needs to be processed. */
2588 		mp = ipsec_early_ah_v6(mp, ira);
2589 		if (mp == NULL)
2590 			return;
2591 
2592 		/*
2593 		 * Reinitialize pointers, as ipsec_early_ah_v6() does
2594 		 * complete pullups.  We don't have to do more pullups
2595 		 * as a result.
2596 		 */
2597 		ip6h = (ip6_t *)mp->b_rptr;
2598 
2599 		if (ira->ira_pktlen - ip_hdr_length < MIN_EHDR_LEN)
2600 			goto pkt_too_short;
2601 
2602 		if (mp->b_cont != NULL &&
2603 		    rptr + ip_hdr_length + MIN_EHDR_LEN > mp->b_wptr) {
2604 			ip6h = ip_pullup(mp, ip_hdr_length + MIN_EHDR_LEN, ira);
2605 			if (ip6h == NULL)
2606 				goto discard;
2607 		}
2608 		rthdr = (ip6_rthdr_t *)(rptr + ip_hdr_length);
2609 		protocol = ira->ira_protocol = rthdr->ip6r_nxt;
2610 		ehdrlen = 8 * (rthdr->ip6r_len + 1);
2611 		if (ira->ira_pktlen - ip_hdr_length < ehdrlen)
2612 			goto pkt_too_short;
2613 		if (mp->b_cont != NULL &&
2614 		    rptr + IPV6_HDR_LEN + ehdrlen > mp->b_wptr) {
2615 			ip6h = ip_pullup(mp, IPV6_HDR_LEN + ehdrlen, ira);
2616 			if (ip6h == NULL)
2617 				goto discard;
2618 			rthdr = (ip6_rthdr_t *)(rptr + ip_hdr_length);
2619 		}
2620 		if (rthdr->ip6r_segleft != 0) {
2621 			/* Not end of source route */
2622 			if (ira->ira_flags &
2623 			    (IRAF_L2DST_MULTICAST|IRAF_L2DST_BROADCAST)) {
2624 				BUMP_MIB(ill->ill_ip_mib,
2625 				    ipIfStatsForwProhibits);
2626 				ip_drop_input("ipIfStatsInForwProhibits",
2627 				    mp, ill);
2628 				freemsg(mp);
2629 				return;
2630 			}
2631 			ip_process_rthdr(mp, ip6h, rthdr, ira);
2632 			return;
2633 		}
2634 		ira->ira_ip_hdr_length += ehdrlen;
2635 		goto repeat;
2636 	}
2637 
2638 	case IPPROTO_AH:
2639 	case IPPROTO_ESP: {
2640 		/*
2641 		 * Fast path for AH/ESP.
2642 		 */
2643 		netstack_t *ns = ipst->ips_netstack;
2644 		ipsec_stack_t *ipss = ns->netstack_ipsec;
2645 
2646 		IP_STAT(ipst, ipsec_proto_ahesp);
2647 
2648 		if (!ipsec_loaded(ipss)) {
2649 			ip_proto_not_sup(mp, ira);
2650 			return;
2651 		}
2652 
2653 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsHCInDelivers);
2654 		/* select inbound SA and have IPsec process the pkt */
2655 		if (protocol == IPPROTO_ESP) {
2656 			esph_t *esph;
2657 
2658 			mp = ipsec_inbound_esp_sa(mp, ira, &esph);
2659 			if (mp == NULL)
2660 				return;
2661 
2662 			ASSERT(esph != NULL);
2663 			ASSERT(ira->ira_flags & IRAF_IPSEC_SECURE);
2664 			ASSERT(ira->ira_ipsec_esp_sa != NULL);
2665 			ASSERT(ira->ira_ipsec_esp_sa->ipsa_input_func != NULL);
2666 
2667 			mp = ira->ira_ipsec_esp_sa->ipsa_input_func(mp, esph,
2668 			    ira);
2669 		} else {
2670 			ah_t *ah;
2671 
2672 			mp = ipsec_inbound_ah_sa(mp, ira, &ah);
2673 			if (mp == NULL)
2674 				return;
2675 
2676 			ASSERT(ah != NULL);
2677 			ASSERT(ira->ira_flags & IRAF_IPSEC_SECURE);
2678 			ASSERT(ira->ira_ipsec_ah_sa != NULL);
2679 			ASSERT(ira->ira_ipsec_ah_sa->ipsa_input_func != NULL);
2680 			mp = ira->ira_ipsec_ah_sa->ipsa_input_func(mp, ah,
2681 			    ira);
2682 		}
2683 
2684 		if (mp == NULL) {
2685 			/*
2686 			 * Either it failed or is pending. In the former case
2687 			 * ipIfStatsInDiscards was increased.
2688 			 */
2689 			return;
2690 		}
2691 		/* we're done with IPsec processing, send it up */
2692 		ip_input_post_ipsec(mp, ira);
2693 		return;
2694 	}
2695 	case IPPROTO_NONE:
2696 		/* All processing is done. Count as "delivered". */
2697 		freemsg(mp);
2698 		BUMP_MIB(ill->ill_ip_mib, ipIfStatsHCInDelivers);
2699 		return;
2700 
2701 	case IPPROTO_ENCAP:
2702 	case IPPROTO_IPV6:
2703 		/* iptun will verify trusted label */
2704 		connp = ipcl_classify_v6(mp, protocol, ip_hdr_length,
2705 		    ira, ipst);
2706 		if (connp != NULL) {
2707 			BUMP_MIB(ill->ill_ip_mib, ipIfStatsHCInDelivers);
2708 			ira->ira_ill = ira->ira_rill = NULL;
2709 			connp->conn_recv(connp, mp, NULL, ira);
2710 			CONN_DEC_REF(connp);
2711 			ira->ira_ill = ill;
2712 			ira->ira_rill = rill;
2713 			return;
2714 		}
2715 		/* FALLTHRU */
2716 	default:
2717 		/*
2718 		 * On a labeled system, we have to check whether the zone
2719 		 * itself is permitted to receive raw traffic.
2720 		 */
2721 		if (ira->ira_flags & IRAF_SYSTEM_LABELED) {
2722 			if (!tsol_can_accept_raw(mp, ira, B_FALSE)) {
2723 				BUMP_MIB(ill->ill_ip_mib, ipIfStatsInDiscards);
2724 				ip_drop_input("ipIfStatsInDiscards", mp, ill);
2725 				freemsg(mp);
2726 				return;
2727 			}
2728 		}
2729 		break;
2730 	}
2731 
2732 	/*
2733 	 * The above input functions may have returned the pulled up message.
2734 	 * So ip6h need to be reinitialized.
2735 	 */
2736 	ip6h = (ip6_t *)mp->b_rptr;
2737 	ira->ira_protocol = protocol;
2738 	if (ipst->ips_ipcl_proto_fanout_v6[protocol].connf_head == NULL) {
2739 		/* No user-level listener for these packets packets */
2740 		ip_proto_not_sup(mp, ira);
2741 		return;
2742 	}
2743 
2744 	/*
2745 	 * Handle fanout to raw sockets.  There
2746 	 * can be more than one stream bound to a particular
2747 	 * protocol.  When this is the case, each one gets a copy
2748 	 * of any incoming packets.
2749 	 */
2750 	ASSERT(ira->ira_protocol == protocol);
2751 	ip_fanout_proto_v6(mp, ip6h, ira);
2752 	return;
2753 
2754 pkt_too_short:
2755 	BUMP_MIB(ill->ill_ip_mib, ipIfStatsInTruncatedPkts);
2756 	ip_drop_input("ipIfStatsInTruncatedPkts", mp, ill);
2757 	freemsg(mp);
2758 	return;
2759 
2760 discard:
2761 	BUMP_MIB(ill->ill_ip_mib, ipIfStatsInDiscards);
2762 	ip_drop_input("ipIfStatsInDiscards", mp, ill);
2763 	freemsg(mp);
2764 #undef rptr
2765 }
2766