xref: /titanic_51/usr/src/uts/common/inet/ip/ipclassifier.c (revision 63251bc7f1ca38259078c48e316fee4ed66d4e93)
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  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /*
27  * IP PACKET CLASSIFIER
28  *
29  * The IP packet classifier provides mapping between IP packets and persistent
30  * connection state for connection-oriented protocols. It also provides
31  * interface for managing connection states.
32  *
33  * The connection state is kept in conn_t data structure and contains, among
34  * other things:
35  *
36  *	o local/remote address and ports
37  *	o Transport protocol
38  *	o squeue for the connection (for TCP only)
39  *	o reference counter
40  *	o Connection state
41  *	o hash table linkage
42  *	o interface/ire information
43  *	o credentials
44  *	o ipsec policy
45  *	o send and receive functions.
46  *	o mutex lock.
47  *
48  * Connections use a reference counting scheme. They are freed when the
49  * reference counter drops to zero. A reference is incremented when connection
50  * is placed in a list or table, when incoming packet for the connection arrives
51  * and when connection is processed via squeue (squeue processing may be
52  * asynchronous and the reference protects the connection from being destroyed
53  * before its processing is finished).
54  *
55  * send and receive functions are currently used for TCP only. The send function
56  * determines the IP entry point for the packet once it leaves TCP to be sent to
57  * the destination address. The receive function is used by IP when the packet
58  * should be passed for TCP processing. When a new connection is created these
59  * are set to ip_output() and tcp_input() respectively. During the lifetime of
60  * the connection the send and receive functions may change depending on the
61  * changes in the connection state. For example, Once the connection is bound to
62  * an addresse, the receive function for this connection is set to
63  * tcp_conn_request().  This allows incoming SYNs to go directly into the
64  * listener SYN processing function without going to tcp_input() first.
65  *
66  * Classifier uses several hash tables:
67  *
68  * 	ipcl_conn_fanout:	contains all TCP connections in CONNECTED state
69  *	ipcl_bind_fanout:	contains all connections in BOUND state
70  *	ipcl_proto_fanout:	IPv4 protocol fanout
71  *	ipcl_proto_fanout_v6:	IPv6 protocol fanout
72  *	ipcl_udp_fanout:	contains all UDP connections
73  *	ipcl_globalhash_fanout:	contains all connections
74  *
75  * The ipcl_globalhash_fanout is used for any walkers (like snmp and Clustering)
76  * which need to view all existing connections.
77  *
78  * All tables are protected by per-bucket locks. When both per-bucket lock and
79  * connection lock need to be held, the per-bucket lock should be acquired
80  * first, followed by the connection lock.
81  *
82  * All functions doing search in one of these tables increment a reference
83  * counter on the connection found (if any). This reference should be dropped
84  * when the caller has finished processing the connection.
85  *
86  *
87  * INTERFACES:
88  * ===========
89  *
90  * Connection Lookup:
91  * ------------------
92  *
93  * conn_t *ipcl_classify_v4(mp, protocol, hdr_len, zoneid, ip_stack)
94  * conn_t *ipcl_classify_v6(mp, protocol, hdr_len, zoneid, ip_stack)
95  *
96  * Finds connection for an incoming IPv4 or IPv6 packet. Returns NULL if
97  * it can't find any associated connection. If the connection is found, its
98  * reference counter is incremented.
99  *
100  *	mp:	mblock, containing packet header. The full header should fit
101  *		into a single mblock. It should also contain at least full IP
102  *		and TCP or UDP header.
103  *
104  *	protocol: Either IPPROTO_TCP or IPPROTO_UDP.
105  *
106  *	hdr_len: The size of IP header. It is used to find TCP or UDP header in
107  *		 the packet.
108  *
109  * 	zoneid: The zone in which the returned connection must be; the zoneid
110  *		corresponding to the ire_zoneid on the IRE located for the
111  *		packet's destination address.
112  *
113  *	For TCP connections, the lookup order is as follows:
114  *		5-tuple {src, dst, protocol, local port, remote port}
115  *			lookup in ipcl_conn_fanout table.
116  *		3-tuple {dst, remote port, protocol} lookup in
117  *			ipcl_bind_fanout table.
118  *
119  *	For UDP connections, a 5-tuple {src, dst, protocol, local port,
120  *	remote port} lookup is done on ipcl_udp_fanout. Note that,
121  *	these interfaces do not handle cases where a packets belongs
122  *	to multiple UDP clients, which is handled in IP itself.
123  *
124  * If the destination IRE is ALL_ZONES (indicated by zoneid), then we must
125  * determine which actual zone gets the segment.  This is used only in a
126  * labeled environment.  The matching rules are:
127  *
128  *	- If it's not a multilevel port, then the label on the packet selects
129  *	  the zone.  Unlabeled packets are delivered to the global zone.
130  *
131  *	- If it's a multilevel port, then only the zone registered to receive
132  *	  packets on that port matches.
133  *
134  * Also, in a labeled environment, packet labels need to be checked.  For fully
135  * bound TCP connections, we can assume that the packet label was checked
136  * during connection establishment, and doesn't need to be checked on each
137  * packet.  For others, though, we need to check for strict equality or, for
138  * multilevel ports, membership in the range or set.  This part currently does
139  * a tnrh lookup on each packet, but could be optimized to use cached results
140  * if that were necessary.  (SCTP doesn't come through here, but if it did,
141  * we would apply the same rules as TCP.)
142  *
143  * An implication of the above is that fully-bound TCP sockets must always use
144  * distinct 4-tuples; they can't be discriminated by label alone.
145  *
146  * Note that we cannot trust labels on packets sent to fully-bound UDP sockets,
147  * as there's no connection set-up handshake and no shared state.
148  *
149  * Labels on looped-back packets within a single zone do not need to be
150  * checked, as all processes in the same zone have the same label.
151  *
152  * Finally, for unlabeled packets received by a labeled system, special rules
153  * apply.  We consider only the MLP if there is one.  Otherwise, we prefer a
154  * socket in the zone whose label matches the default label of the sender, if
155  * any.  In any event, the receiving socket must have SO_MAC_EXEMPT set and the
156  * receiver's label must dominate the sender's default label.
157  *
158  * conn_t *ipcl_tcp_lookup_reversed_ipv4(ipha_t *, tcph_t *, int, ip_stack);
159  * conn_t *ipcl_tcp_lookup_reversed_ipv6(ip6_t *, tcpha_t *, int, uint_t,
160  *					 ip_stack);
161  *
162  *	Lookup routine to find a exact match for {src, dst, local port,
163  *	remote port) for TCP connections in ipcl_conn_fanout. The address and
164  *	ports are read from the IP and TCP header respectively.
165  *
166  * conn_t	*ipcl_lookup_listener_v4(lport, laddr, protocol,
167  *					 zoneid, ip_stack);
168  * conn_t	*ipcl_lookup_listener_v6(lport, laddr, protocol, ifindex,
169  *					 zoneid, ip_stack);
170  *
171  * 	Lookup routine to find a listener with the tuple {lport, laddr,
172  * 	protocol} in the ipcl_bind_fanout table. For IPv6, an additional
173  * 	parameter interface index is also compared.
174  *
175  * void ipcl_walk(func, arg, ip_stack)
176  *
177  * 	Apply 'func' to every connection available. The 'func' is called as
178  *	(*func)(connp, arg). The walk is non-atomic so connections may be
179  *	created and destroyed during the walk. The CONN_CONDEMNED and
180  *	CONN_INCIPIENT flags ensure that connections which are newly created
181  *	or being destroyed are not selected by the walker.
182  *
183  * Table Updates
184  * -------------
185  *
186  * int ipcl_conn_insert(connp, protocol, src, dst, ports)
187  * int ipcl_conn_insert_v6(connp, protocol, src, dst, ports, ifindex)
188  *
189  *	Insert 'connp' in the ipcl_conn_fanout.
190  *	Arguements :
191  *		connp		conn_t to be inserted
192  *		protocol	connection protocol
193  *		src		source address
194  *		dst		destination address
195  *		ports		local and remote port
196  *		ifindex		interface index for IPv6 connections
197  *
198  *	Return value :
199  *		0		if connp was inserted
200  *		EADDRINUSE	if the connection with the same tuple
201  *				already exists.
202  *
203  * int ipcl_bind_insert(connp, protocol, src, lport);
204  * int ipcl_bind_insert_v6(connp, protocol, src, lport);
205  *
206  * 	Insert 'connp' in ipcl_bind_fanout.
207  * 	Arguements :
208  * 		connp		conn_t to be inserted
209  * 		protocol	connection protocol
210  * 		src		source address connection wants
211  * 				to bind to
212  * 		lport		local port connection wants to
213  * 				bind to
214  *
215  *
216  * void ipcl_hash_remove(connp);
217  *
218  * 	Removes the 'connp' from the connection fanout table.
219  *
220  * Connection Creation/Destruction
221  * -------------------------------
222  *
223  * conn_t *ipcl_conn_create(type, sleep, netstack_t *)
224  *
225  * 	Creates a new conn based on the type flag, inserts it into
226  * 	globalhash table.
227  *
228  *	type:	This flag determines the type of conn_t which needs to be
229  *		created i.e., which kmem_cache it comes from.
230  *		IPCL_TCPCONN	indicates a TCP connection
231  *		IPCL_SCTPCONN	indicates a SCTP connection
232  *		IPCL_UDPCONN	indicates a UDP conn_t.
233  *		IPCL_RAWIPCONN	indicates a RAWIP/ICMP conn_t.
234  *		IPCL_RTSCONN	indicates a RTS conn_t.
235  *		IPCL_IPCCONN	indicates all other connections.
236  *
237  * void ipcl_conn_destroy(connp)
238  *
239  * 	Destroys the connection state, removes it from the global
240  * 	connection hash table and frees its memory.
241  */
242 
243 #include <sys/types.h>
244 #include <sys/stream.h>
245 #include <sys/stropts.h>
246 #include <sys/sysmacros.h>
247 #include <sys/strsubr.h>
248 #include <sys/strsun.h>
249 #define	_SUN_TPI_VERSION 2
250 #include <sys/ddi.h>
251 #include <sys/cmn_err.h>
252 #include <sys/debug.h>
253 
254 #include <sys/systm.h>
255 #include <sys/param.h>
256 #include <sys/kmem.h>
257 #include <sys/isa_defs.h>
258 #include <inet/common.h>
259 #include <netinet/ip6.h>
260 #include <netinet/icmp6.h>
261 
262 #include <inet/ip.h>
263 #include <inet/ip6.h>
264 #include <inet/ip_ndp.h>
265 #include <inet/ip_impl.h>
266 #include <inet/udp_impl.h>
267 #include <inet/sctp_ip.h>
268 #include <inet/sctp/sctp_impl.h>
269 #include <inet/rawip_impl.h>
270 #include <inet/rts_impl.h>
271 
272 #include <sys/cpuvar.h>
273 
274 #include <inet/ipclassifier.h>
275 #include <inet/tcp.h>
276 #include <inet/ipsec_impl.h>
277 
278 #include <sys/tsol/tnet.h>
279 #include <sys/sockio.h>
280 
281 #ifdef DEBUG
282 #define	IPCL_DEBUG
283 #else
284 #undef	IPCL_DEBUG
285 #endif
286 
287 #ifdef	IPCL_DEBUG
288 int	ipcl_debug_level = 0;
289 #define	IPCL_DEBUG_LVL(level, args)	\
290 	if (ipcl_debug_level  & level) { printf args; }
291 #else
292 #define	IPCL_DEBUG_LVL(level, args) {; }
293 #endif
294 /* Old value for compatibility. Setable in /etc/system */
295 uint_t tcp_conn_hash_size = 0;
296 
297 /* New value. Zero means choose automatically.  Setable in /etc/system */
298 uint_t ipcl_conn_hash_size = 0;
299 uint_t ipcl_conn_hash_memfactor = 8192;
300 uint_t ipcl_conn_hash_maxsize = 82500;
301 
302 /* bind/udp fanout table size */
303 uint_t ipcl_bind_fanout_size = 512;
304 uint_t ipcl_udp_fanout_size = 16384;
305 
306 /* Raw socket fanout size.  Must be a power of 2. */
307 uint_t ipcl_raw_fanout_size = 256;
308 
309 /*
310  * Power of 2^N Primes useful for hashing for N of 0-28,
311  * these primes are the nearest prime <= 2^N - 2^(N-2).
312  */
313 
314 #define	P2Ps() {0, 0, 0, 5, 11, 23, 47, 89, 191, 383, 761, 1531, 3067,	\
315 		6143, 12281, 24571, 49139, 98299, 196597, 393209,	\
316 		786431, 1572853, 3145721, 6291449, 12582893, 25165813,	\
317 		50331599, 100663291, 201326557, 0}
318 
319 /*
320  * wrapper structure to ensure that conn and what follows it (tcp_t, etc)
321  * are aligned on cache lines.
322  */
323 typedef union itc_s {
324 	conn_t	itc_conn;
325 	char	itcu_filler[CACHE_ALIGN(conn_s)];
326 } itc_t;
327 
328 struct kmem_cache  *tcp_conn_cache;
329 struct kmem_cache  *ip_conn_cache;
330 struct kmem_cache  *ip_helper_stream_cache;
331 extern struct kmem_cache  *sctp_conn_cache;
332 extern struct kmem_cache  *tcp_sack_info_cache;
333 extern struct kmem_cache  *tcp_iphc_cache;
334 struct kmem_cache  *udp_conn_cache;
335 struct kmem_cache  *rawip_conn_cache;
336 struct kmem_cache  *rts_conn_cache;
337 
338 extern void	tcp_timermp_free(tcp_t *);
339 extern mblk_t	*tcp_timermp_alloc(int);
340 
341 static int	ip_conn_constructor(void *, void *, int);
342 static void	ip_conn_destructor(void *, void *);
343 
344 static int	tcp_conn_constructor(void *, void *, int);
345 static void	tcp_conn_destructor(void *, void *);
346 
347 static int	udp_conn_constructor(void *, void *, int);
348 static void	udp_conn_destructor(void *, void *);
349 
350 static int	rawip_conn_constructor(void *, void *, int);
351 static void	rawip_conn_destructor(void *, void *);
352 
353 static int	rts_conn_constructor(void *, void *, int);
354 static void	rts_conn_destructor(void *, void *);
355 
356 static int	ip_helper_stream_constructor(void *, void *, int);
357 static void	ip_helper_stream_destructor(void *, void *);
358 
359 boolean_t	ip_use_helper_cache = B_TRUE;
360 
361 /*
362  * Hook functions to enable cluster networking
363  * On non-clustered systems these vectors must always be NULL.
364  */
365 extern void	(*cl_inet_listen)(netstackid_t, uint8_t, sa_family_t,
366 		    uint8_t *, in_port_t, void *);
367 extern void	(*cl_inet_unlisten)(netstackid_t, uint8_t, sa_family_t,
368 		    uint8_t *, in_port_t, void *);
369 
370 #ifdef	IPCL_DEBUG
371 #define	INET_NTOA_BUFSIZE	18
372 
373 static char *
374 inet_ntoa_r(uint32_t in, char *b)
375 {
376 	unsigned char	*p;
377 
378 	p = (unsigned char *)&in;
379 	(void) sprintf(b, "%d.%d.%d.%d", p[0], p[1], p[2], p[3]);
380 	return (b);
381 }
382 #endif
383 
384 /*
385  * Global (for all stack instances) init routine
386  */
387 void
388 ipcl_g_init(void)
389 {
390 	ip_conn_cache = kmem_cache_create("ip_conn_cache",
391 	    sizeof (conn_t), CACHE_ALIGN_SIZE,
392 	    ip_conn_constructor, ip_conn_destructor,
393 	    NULL, NULL, NULL, 0);
394 
395 	tcp_conn_cache = kmem_cache_create("tcp_conn_cache",
396 	    sizeof (itc_t) + sizeof (tcp_t), CACHE_ALIGN_SIZE,
397 	    tcp_conn_constructor, tcp_conn_destructor,
398 	    NULL, NULL, NULL, 0);
399 
400 	udp_conn_cache = kmem_cache_create("udp_conn_cache",
401 	    sizeof (itc_t) + sizeof (udp_t), CACHE_ALIGN_SIZE,
402 	    udp_conn_constructor, udp_conn_destructor,
403 	    NULL, NULL, NULL, 0);
404 
405 	rawip_conn_cache = kmem_cache_create("rawip_conn_cache",
406 	    sizeof (itc_t) + sizeof (icmp_t), CACHE_ALIGN_SIZE,
407 	    rawip_conn_constructor, rawip_conn_destructor,
408 	    NULL, NULL, NULL, 0);
409 
410 	rts_conn_cache = kmem_cache_create("rts_conn_cache",
411 	    sizeof (itc_t) + sizeof (rts_t), CACHE_ALIGN_SIZE,
412 	    rts_conn_constructor, rts_conn_destructor,
413 	    NULL, NULL, NULL, 0);
414 
415 	if (ip_use_helper_cache) {
416 		ip_helper_stream_cache = kmem_cache_create
417 		    ("ip_helper_stream_cache", sizeof (ip_helper_stream_info_t),
418 		    CACHE_ALIGN_SIZE, ip_helper_stream_constructor,
419 		    ip_helper_stream_destructor, NULL, NULL, NULL, 0);
420 	} else {
421 		ip_helper_stream_cache = NULL;
422 	}
423 }
424 
425 /*
426  * ipclassifier intialization routine, sets up hash tables.
427  */
428 void
429 ipcl_init(ip_stack_t *ipst)
430 {
431 	int i;
432 	int sizes[] = P2Ps();
433 
434 	/*
435 	 * Calculate size of conn fanout table from /etc/system settings
436 	 */
437 	if (ipcl_conn_hash_size != 0) {
438 		ipst->ips_ipcl_conn_fanout_size = ipcl_conn_hash_size;
439 	} else if (tcp_conn_hash_size != 0) {
440 		ipst->ips_ipcl_conn_fanout_size = tcp_conn_hash_size;
441 	} else {
442 		extern pgcnt_t freemem;
443 
444 		ipst->ips_ipcl_conn_fanout_size =
445 		    (freemem * PAGESIZE) / ipcl_conn_hash_memfactor;
446 
447 		if (ipst->ips_ipcl_conn_fanout_size > ipcl_conn_hash_maxsize) {
448 			ipst->ips_ipcl_conn_fanout_size =
449 			    ipcl_conn_hash_maxsize;
450 		}
451 	}
452 
453 	for (i = 9; i < sizeof (sizes) / sizeof (*sizes) - 1; i++) {
454 		if (sizes[i] >= ipst->ips_ipcl_conn_fanout_size) {
455 			break;
456 		}
457 	}
458 	if ((ipst->ips_ipcl_conn_fanout_size = sizes[i]) == 0) {
459 		/* Out of range, use the 2^16 value */
460 		ipst->ips_ipcl_conn_fanout_size = sizes[16];
461 	}
462 
463 	/* Take values from /etc/system */
464 	ipst->ips_ipcl_bind_fanout_size = ipcl_bind_fanout_size;
465 	ipst->ips_ipcl_udp_fanout_size = ipcl_udp_fanout_size;
466 	ipst->ips_ipcl_raw_fanout_size = ipcl_raw_fanout_size;
467 
468 	ASSERT(ipst->ips_ipcl_conn_fanout == NULL);
469 
470 	ipst->ips_ipcl_conn_fanout = kmem_zalloc(
471 	    ipst->ips_ipcl_conn_fanout_size * sizeof (connf_t), KM_SLEEP);
472 
473 	for (i = 0; i < ipst->ips_ipcl_conn_fanout_size; i++) {
474 		mutex_init(&ipst->ips_ipcl_conn_fanout[i].connf_lock, NULL,
475 		    MUTEX_DEFAULT, NULL);
476 	}
477 
478 	ipst->ips_ipcl_bind_fanout = kmem_zalloc(
479 	    ipst->ips_ipcl_bind_fanout_size * sizeof (connf_t), KM_SLEEP);
480 
481 	for (i = 0; i < ipst->ips_ipcl_bind_fanout_size; i++) {
482 		mutex_init(&ipst->ips_ipcl_bind_fanout[i].connf_lock, NULL,
483 		    MUTEX_DEFAULT, NULL);
484 	}
485 
486 	ipst->ips_ipcl_proto_fanout = kmem_zalloc(IPPROTO_MAX *
487 	    sizeof (connf_t), KM_SLEEP);
488 	for (i = 0; i < IPPROTO_MAX; i++) {
489 		mutex_init(&ipst->ips_ipcl_proto_fanout[i].connf_lock, NULL,
490 		    MUTEX_DEFAULT, NULL);
491 	}
492 
493 	ipst->ips_ipcl_proto_fanout_v6 = kmem_zalloc(IPPROTO_MAX *
494 	    sizeof (connf_t), KM_SLEEP);
495 	for (i = 0; i < IPPROTO_MAX; i++) {
496 		mutex_init(&ipst->ips_ipcl_proto_fanout_v6[i].connf_lock, NULL,
497 		    MUTEX_DEFAULT, NULL);
498 	}
499 
500 	ipst->ips_rts_clients = kmem_zalloc(sizeof (connf_t), KM_SLEEP);
501 	mutex_init(&ipst->ips_rts_clients->connf_lock,
502 	    NULL, MUTEX_DEFAULT, NULL);
503 
504 	ipst->ips_ipcl_udp_fanout = kmem_zalloc(
505 	    ipst->ips_ipcl_udp_fanout_size * sizeof (connf_t), KM_SLEEP);
506 	for (i = 0; i < ipst->ips_ipcl_udp_fanout_size; i++) {
507 		mutex_init(&ipst->ips_ipcl_udp_fanout[i].connf_lock, NULL,
508 		    MUTEX_DEFAULT, NULL);
509 	}
510 
511 	ipst->ips_ipcl_raw_fanout = kmem_zalloc(
512 	    ipst->ips_ipcl_raw_fanout_size * sizeof (connf_t), KM_SLEEP);
513 	for (i = 0; i < ipst->ips_ipcl_raw_fanout_size; i++) {
514 		mutex_init(&ipst->ips_ipcl_raw_fanout[i].connf_lock, NULL,
515 		    MUTEX_DEFAULT, NULL);
516 	}
517 
518 	ipst->ips_ipcl_globalhash_fanout = kmem_zalloc(
519 	    sizeof (connf_t) * CONN_G_HASH_SIZE, KM_SLEEP);
520 	for (i = 0; i < CONN_G_HASH_SIZE; i++) {
521 		mutex_init(&ipst->ips_ipcl_globalhash_fanout[i].connf_lock,
522 		    NULL, MUTEX_DEFAULT, NULL);
523 	}
524 }
525 
526 void
527 ipcl_g_destroy(void)
528 {
529 	kmem_cache_destroy(ip_conn_cache);
530 	kmem_cache_destroy(tcp_conn_cache);
531 	kmem_cache_destroy(udp_conn_cache);
532 	kmem_cache_destroy(rawip_conn_cache);
533 	kmem_cache_destroy(rts_conn_cache);
534 }
535 
536 /*
537  * All user-level and kernel use of the stack must be gone
538  * by now.
539  */
540 void
541 ipcl_destroy(ip_stack_t *ipst)
542 {
543 	int i;
544 
545 	for (i = 0; i < ipst->ips_ipcl_conn_fanout_size; i++) {
546 		ASSERT(ipst->ips_ipcl_conn_fanout[i].connf_head == NULL);
547 		mutex_destroy(&ipst->ips_ipcl_conn_fanout[i].connf_lock);
548 	}
549 	kmem_free(ipst->ips_ipcl_conn_fanout, ipst->ips_ipcl_conn_fanout_size *
550 	    sizeof (connf_t));
551 	ipst->ips_ipcl_conn_fanout = NULL;
552 
553 	for (i = 0; i < ipst->ips_ipcl_bind_fanout_size; i++) {
554 		ASSERT(ipst->ips_ipcl_bind_fanout[i].connf_head == NULL);
555 		mutex_destroy(&ipst->ips_ipcl_bind_fanout[i].connf_lock);
556 	}
557 	kmem_free(ipst->ips_ipcl_bind_fanout, ipst->ips_ipcl_bind_fanout_size *
558 	    sizeof (connf_t));
559 	ipst->ips_ipcl_bind_fanout = NULL;
560 
561 	for (i = 0; i < IPPROTO_MAX; i++) {
562 		ASSERT(ipst->ips_ipcl_proto_fanout[i].connf_head == NULL);
563 		mutex_destroy(&ipst->ips_ipcl_proto_fanout[i].connf_lock);
564 	}
565 	kmem_free(ipst->ips_ipcl_proto_fanout, IPPROTO_MAX * sizeof (connf_t));
566 	ipst->ips_ipcl_proto_fanout = NULL;
567 
568 	for (i = 0; i < IPPROTO_MAX; i++) {
569 		ASSERT(ipst->ips_ipcl_proto_fanout_v6[i].connf_head == NULL);
570 		mutex_destroy(&ipst->ips_ipcl_proto_fanout_v6[i].connf_lock);
571 	}
572 	kmem_free(ipst->ips_ipcl_proto_fanout_v6,
573 	    IPPROTO_MAX * sizeof (connf_t));
574 	ipst->ips_ipcl_proto_fanout_v6 = NULL;
575 
576 	for (i = 0; i < ipst->ips_ipcl_udp_fanout_size; i++) {
577 		ASSERT(ipst->ips_ipcl_udp_fanout[i].connf_head == NULL);
578 		mutex_destroy(&ipst->ips_ipcl_udp_fanout[i].connf_lock);
579 	}
580 	kmem_free(ipst->ips_ipcl_udp_fanout, ipst->ips_ipcl_udp_fanout_size *
581 	    sizeof (connf_t));
582 	ipst->ips_ipcl_udp_fanout = NULL;
583 
584 	for (i = 0; i < ipst->ips_ipcl_raw_fanout_size; i++) {
585 		ASSERT(ipst->ips_ipcl_raw_fanout[i].connf_head == NULL);
586 		mutex_destroy(&ipst->ips_ipcl_raw_fanout[i].connf_lock);
587 	}
588 	kmem_free(ipst->ips_ipcl_raw_fanout, ipst->ips_ipcl_raw_fanout_size *
589 	    sizeof (connf_t));
590 	ipst->ips_ipcl_raw_fanout = NULL;
591 
592 	for (i = 0; i < CONN_G_HASH_SIZE; i++) {
593 		ASSERT(ipst->ips_ipcl_globalhash_fanout[i].connf_head == NULL);
594 		mutex_destroy(&ipst->ips_ipcl_globalhash_fanout[i].connf_lock);
595 	}
596 	kmem_free(ipst->ips_ipcl_globalhash_fanout,
597 	    sizeof (connf_t) * CONN_G_HASH_SIZE);
598 	ipst->ips_ipcl_globalhash_fanout = NULL;
599 
600 	ASSERT(ipst->ips_rts_clients->connf_head == NULL);
601 	mutex_destroy(&ipst->ips_rts_clients->connf_lock);
602 	kmem_free(ipst->ips_rts_clients, sizeof (connf_t));
603 	ipst->ips_rts_clients = NULL;
604 }
605 
606 /*
607  * conn creation routine. initialize the conn, sets the reference
608  * and inserts it in the global hash table.
609  */
610 conn_t *
611 ipcl_conn_create(uint32_t type, int sleep, netstack_t *ns)
612 {
613 	conn_t	*connp;
614 	sctp_stack_t *sctps;
615 	struct kmem_cache *conn_cache;
616 
617 	switch (type) {
618 	case IPCL_SCTPCONN:
619 		if ((connp = kmem_cache_alloc(sctp_conn_cache, sleep)) == NULL)
620 			return (NULL);
621 		sctp_conn_init(connp);
622 		sctps = ns->netstack_sctp;
623 		SCTP_G_Q_REFHOLD(sctps);
624 		netstack_hold(ns);
625 		connp->conn_netstack = ns;
626 		return (connp);
627 
628 	case IPCL_TCPCONN:
629 		conn_cache = tcp_conn_cache;
630 		break;
631 
632 	case IPCL_UDPCONN:
633 		conn_cache = udp_conn_cache;
634 		break;
635 
636 	case IPCL_RAWIPCONN:
637 		conn_cache = rawip_conn_cache;
638 		break;
639 
640 	case IPCL_RTSCONN:
641 		conn_cache = rts_conn_cache;
642 		break;
643 
644 	case IPCL_IPCCONN:
645 		conn_cache = ip_conn_cache;
646 		break;
647 
648 	default:
649 		connp = NULL;
650 		ASSERT(0);
651 	}
652 
653 	if ((connp = kmem_cache_alloc(conn_cache, sleep)) == NULL)
654 		return (NULL);
655 
656 	connp->conn_ref = 1;
657 	netstack_hold(ns);
658 	connp->conn_netstack = ns;
659 	ipcl_globalhash_insert(connp);
660 	return (connp);
661 }
662 
663 void
664 ipcl_conn_destroy(conn_t *connp)
665 {
666 	mblk_t	*mp;
667 	netstack_t	*ns = connp->conn_netstack;
668 
669 	ASSERT(!MUTEX_HELD(&connp->conn_lock));
670 	ASSERT(connp->conn_ref == 0);
671 	ASSERT(connp->conn_ire_cache == NULL);
672 
673 	DTRACE_PROBE1(conn__destroy, conn_t *, connp);
674 
675 	if (connp->conn_peercred != NULL) {
676 		crfree(connp->conn_peercred);
677 		connp->conn_peercred = NULL;
678 	}
679 
680 	if (connp->conn_cred != NULL) {
681 		crfree(connp->conn_cred);
682 		connp->conn_cred = NULL;
683 	}
684 
685 	ipcl_globalhash_remove(connp);
686 
687 	/* FIXME: add separate tcp_conn_free()? */
688 	if (connp->conn_flags & IPCL_TCPCONN) {
689 		tcp_t	*tcp = connp->conn_tcp;
690 		tcp_stack_t *tcps;
691 
692 		ASSERT(tcp != NULL);
693 		tcps = tcp->tcp_tcps;
694 		if (tcps != NULL) {
695 			if (connp->conn_latch != NULL) {
696 				IPLATCH_REFRELE(connp->conn_latch, ns);
697 				connp->conn_latch = NULL;
698 			}
699 			if (connp->conn_policy != NULL) {
700 				IPPH_REFRELE(connp->conn_policy, ns);
701 				connp->conn_policy = NULL;
702 			}
703 			tcp->tcp_tcps = NULL;
704 			TCPS_REFRELE(tcps);
705 		}
706 
707 		tcp_free(tcp);
708 		mp = tcp->tcp_timercache;
709 		tcp->tcp_cred = NULL;
710 
711 		if (tcp->tcp_sack_info != NULL) {
712 			bzero(tcp->tcp_sack_info, sizeof (tcp_sack_info_t));
713 			kmem_cache_free(tcp_sack_info_cache,
714 			    tcp->tcp_sack_info);
715 		}
716 		if (tcp->tcp_iphc != NULL) {
717 			if (tcp->tcp_hdr_grown) {
718 				kmem_free(tcp->tcp_iphc, tcp->tcp_iphc_len);
719 			} else {
720 				bzero(tcp->tcp_iphc, tcp->tcp_iphc_len);
721 				kmem_cache_free(tcp_iphc_cache, tcp->tcp_iphc);
722 			}
723 			tcp->tcp_iphc_len = 0;
724 		}
725 		ASSERT(tcp->tcp_iphc_len == 0);
726 
727 		/*
728 		 * tcp_rsrv_mp can be NULL if tcp_get_conn() fails to allocate
729 		 * the mblk.
730 		 */
731 		if (tcp->tcp_rsrv_mp != NULL) {
732 			freeb(tcp->tcp_rsrv_mp);
733 			tcp->tcp_rsrv_mp = NULL;
734 			mutex_destroy(&tcp->tcp_rsrv_mp_lock);
735 		}
736 
737 		ASSERT(connp->conn_latch == NULL);
738 		ASSERT(connp->conn_policy == NULL);
739 
740 		if (ns != NULL) {
741 			ASSERT(tcp->tcp_tcps == NULL);
742 			connp->conn_netstack = NULL;
743 			netstack_rele(ns);
744 		}
745 
746 		ipcl_conn_cleanup(connp);
747 		connp->conn_flags = IPCL_TCPCONN;
748 		bzero(tcp, sizeof (tcp_t));
749 
750 		tcp->tcp_timercache = mp;
751 		tcp->tcp_connp = connp;
752 		kmem_cache_free(tcp_conn_cache, connp);
753 		return;
754 	}
755 	if (connp->conn_latch != NULL) {
756 		IPLATCH_REFRELE(connp->conn_latch, connp->conn_netstack);
757 		connp->conn_latch = NULL;
758 	}
759 	if (connp->conn_policy != NULL) {
760 		IPPH_REFRELE(connp->conn_policy, connp->conn_netstack);
761 		connp->conn_policy = NULL;
762 	}
763 	if (connp->conn_ipsec_opt_mp != NULL) {
764 		freemsg(connp->conn_ipsec_opt_mp);
765 		connp->conn_ipsec_opt_mp = NULL;
766 	}
767 
768 	if (connp->conn_flags & IPCL_SCTPCONN) {
769 		ASSERT(ns != NULL);
770 		sctp_free(connp);
771 		return;
772 	}
773 
774 	if (ns != NULL) {
775 		connp->conn_netstack = NULL;
776 		netstack_rele(ns);
777 	}
778 
779 	ipcl_conn_cleanup(connp);
780 
781 	/* leave conn_priv aka conn_udp, conn_icmp, etc in place. */
782 	if (connp->conn_flags & IPCL_UDPCONN) {
783 		connp->conn_flags = IPCL_UDPCONN;
784 		kmem_cache_free(udp_conn_cache, connp);
785 	} else if (connp->conn_flags & IPCL_RAWIPCONN) {
786 
787 		connp->conn_flags = IPCL_RAWIPCONN;
788 		connp->conn_ulp = IPPROTO_ICMP;
789 		kmem_cache_free(rawip_conn_cache, connp);
790 	} else if (connp->conn_flags & IPCL_RTSCONN) {
791 		connp->conn_flags = IPCL_RTSCONN;
792 		kmem_cache_free(rts_conn_cache, connp);
793 	} else {
794 		connp->conn_flags = IPCL_IPCCONN;
795 		ASSERT(connp->conn_flags & IPCL_IPCCONN);
796 		ASSERT(connp->conn_priv == NULL);
797 		kmem_cache_free(ip_conn_cache, connp);
798 	}
799 }
800 
801 /*
802  * Running in cluster mode - deregister listener information
803  */
804 
805 static void
806 ipcl_conn_unlisten(conn_t *connp)
807 {
808 	ASSERT((connp->conn_flags & IPCL_CL_LISTENER) != 0);
809 	ASSERT(connp->conn_lport != 0);
810 
811 	if (cl_inet_unlisten != NULL) {
812 		sa_family_t	addr_family;
813 		uint8_t		*laddrp;
814 
815 		if (connp->conn_pkt_isv6) {
816 			addr_family = AF_INET6;
817 			laddrp = (uint8_t *)&connp->conn_bound_source_v6;
818 		} else {
819 			addr_family = AF_INET;
820 			laddrp = (uint8_t *)&connp->conn_bound_source;
821 		}
822 		(*cl_inet_unlisten)(connp->conn_netstack->netstack_stackid,
823 		    IPPROTO_TCP, addr_family, laddrp, connp->conn_lport, NULL);
824 	}
825 	connp->conn_flags &= ~IPCL_CL_LISTENER;
826 }
827 
828 /*
829  * We set the IPCL_REMOVED flag (instead of clearing the flag indicating
830  * which table the conn belonged to). So for debugging we can see which hash
831  * table this connection was in.
832  */
833 #define	IPCL_HASH_REMOVE(connp)	{					\
834 	connf_t	*connfp = (connp)->conn_fanout;				\
835 	ASSERT(!MUTEX_HELD(&((connp)->conn_lock)));			\
836 	if (connfp != NULL) {						\
837 		IPCL_DEBUG_LVL(4, ("IPCL_HASH_REMOVE: connp %p",	\
838 		    (void *)(connp)));					\
839 		mutex_enter(&connfp->connf_lock);			\
840 		if ((connp)->conn_next != NULL)				\
841 			(connp)->conn_next->conn_prev =			\
842 			    (connp)->conn_prev;				\
843 		if ((connp)->conn_prev != NULL)				\
844 			(connp)->conn_prev->conn_next =			\
845 			    (connp)->conn_next;				\
846 		else							\
847 			connfp->connf_head = (connp)->conn_next;	\
848 		(connp)->conn_fanout = NULL;				\
849 		(connp)->conn_next = NULL;				\
850 		(connp)->conn_prev = NULL;				\
851 		(connp)->conn_flags |= IPCL_REMOVED;			\
852 		if (((connp)->conn_flags & IPCL_CL_LISTENER) != 0)	\
853 			ipcl_conn_unlisten((connp));			\
854 		CONN_DEC_REF((connp));					\
855 		mutex_exit(&connfp->connf_lock);			\
856 	}								\
857 }
858 
859 void
860 ipcl_hash_remove(conn_t *connp)
861 {
862 	IPCL_HASH_REMOVE(connp);
863 }
864 
865 /*
866  * The whole purpose of this function is allow removal of
867  * a conn_t from the connected hash for timewait reclaim.
868  * This is essentially a TW reclaim fastpath where timewait
869  * collector checks under fanout lock (so no one else can
870  * get access to the conn_t) that refcnt is 2 i.e. one for
871  * TCP and one for the classifier hash list. If ref count
872  * is indeed 2, we can just remove the conn under lock and
873  * avoid cleaning up the conn under squeue. This gives us
874  * improved performance.
875  */
876 void
877 ipcl_hash_remove_locked(conn_t *connp, connf_t	*connfp)
878 {
879 	ASSERT(MUTEX_HELD(&connfp->connf_lock));
880 	ASSERT(MUTEX_HELD(&connp->conn_lock));
881 	ASSERT((connp->conn_flags & IPCL_CL_LISTENER) == 0);
882 
883 	if ((connp)->conn_next != NULL) {
884 		(connp)->conn_next->conn_prev = (connp)->conn_prev;
885 	}
886 	if ((connp)->conn_prev != NULL) {
887 		(connp)->conn_prev->conn_next = (connp)->conn_next;
888 	} else {
889 		connfp->connf_head = (connp)->conn_next;
890 	}
891 	(connp)->conn_fanout = NULL;
892 	(connp)->conn_next = NULL;
893 	(connp)->conn_prev = NULL;
894 	(connp)->conn_flags |= IPCL_REMOVED;
895 	ASSERT((connp)->conn_ref == 2);
896 	(connp)->conn_ref--;
897 }
898 
899 #define	IPCL_HASH_INSERT_CONNECTED_LOCKED(connfp, connp) {		\
900 	ASSERT((connp)->conn_fanout == NULL);				\
901 	ASSERT((connp)->conn_next == NULL);				\
902 	ASSERT((connp)->conn_prev == NULL);				\
903 	if ((connfp)->connf_head != NULL) {				\
904 		(connfp)->connf_head->conn_prev = (connp);		\
905 		(connp)->conn_next = (connfp)->connf_head;		\
906 	}								\
907 	(connp)->conn_fanout = (connfp);				\
908 	(connfp)->connf_head = (connp);					\
909 	(connp)->conn_flags = ((connp)->conn_flags & ~IPCL_REMOVED) |	\
910 	    IPCL_CONNECTED;						\
911 	CONN_INC_REF(connp);						\
912 }
913 
914 #define	IPCL_HASH_INSERT_CONNECTED(connfp, connp) {			\
915 	IPCL_DEBUG_LVL(8, ("IPCL_HASH_INSERT_CONNECTED: connfp %p "	\
916 	    "connp %p", (void *)(connfp), (void *)(connp)));		\
917 	IPCL_HASH_REMOVE((connp));					\
918 	mutex_enter(&(connfp)->connf_lock);				\
919 	IPCL_HASH_INSERT_CONNECTED_LOCKED(connfp, connp);		\
920 	mutex_exit(&(connfp)->connf_lock);				\
921 }
922 
923 #define	IPCL_HASH_INSERT_BOUND(connfp, connp) {				\
924 	conn_t *pconnp = NULL, *nconnp;					\
925 	IPCL_DEBUG_LVL(32, ("IPCL_HASH_INSERT_BOUND: connfp %p "	\
926 	    "connp %p", (void *)connfp, (void *)(connp)));		\
927 	IPCL_HASH_REMOVE((connp));					\
928 	mutex_enter(&(connfp)->connf_lock);				\
929 	nconnp = (connfp)->connf_head;					\
930 	while (nconnp != NULL &&					\
931 	    !_IPCL_V4_MATCH_ANY(nconnp->conn_srcv6)) {			\
932 		pconnp = nconnp;					\
933 		nconnp = nconnp->conn_next;				\
934 	}								\
935 	if (pconnp != NULL) {						\
936 		pconnp->conn_next = (connp);				\
937 		(connp)->conn_prev = pconnp;				\
938 	} else {							\
939 		(connfp)->connf_head = (connp);				\
940 	}								\
941 	if (nconnp != NULL) {						\
942 		(connp)->conn_next = nconnp;				\
943 		nconnp->conn_prev = (connp);				\
944 	}								\
945 	(connp)->conn_fanout = (connfp);				\
946 	(connp)->conn_flags = ((connp)->conn_flags & ~IPCL_REMOVED) |	\
947 	    IPCL_BOUND;							\
948 	CONN_INC_REF(connp);						\
949 	mutex_exit(&(connfp)->connf_lock);				\
950 }
951 
952 #define	IPCL_HASH_INSERT_WILDCARD(connfp, connp) {			\
953 	conn_t **list, *prev, *next;					\
954 	boolean_t isv4mapped =						\
955 	    IN6_IS_ADDR_V4MAPPED(&(connp)->conn_srcv6);			\
956 	IPCL_DEBUG_LVL(32, ("IPCL_HASH_INSERT_WILDCARD: connfp %p "	\
957 	    "connp %p", (void *)(connfp), (void *)(connp)));		\
958 	IPCL_HASH_REMOVE((connp));					\
959 	mutex_enter(&(connfp)->connf_lock);				\
960 	list = &(connfp)->connf_head;					\
961 	prev = NULL;							\
962 	while ((next = *list) != NULL) {				\
963 		if (isv4mapped &&					\
964 		    IN6_IS_ADDR_UNSPECIFIED(&next->conn_srcv6) &&	\
965 		    connp->conn_zoneid == next->conn_zoneid) {		\
966 			(connp)->conn_next = next;			\
967 			if (prev != NULL)				\
968 				prev = next->conn_prev;			\
969 			next->conn_prev = (connp);			\
970 			break;						\
971 		}							\
972 		list = &next->conn_next;				\
973 		prev = next;						\
974 	}								\
975 	(connp)->conn_prev = prev;					\
976 	*list = (connp);						\
977 	(connp)->conn_fanout = (connfp);				\
978 	(connp)->conn_flags = ((connp)->conn_flags & ~IPCL_REMOVED) |	\
979 	    IPCL_BOUND;							\
980 	CONN_INC_REF((connp));						\
981 	mutex_exit(&(connfp)->connf_lock);				\
982 }
983 
984 void
985 ipcl_hash_insert_wildcard(connf_t *connfp, conn_t *connp)
986 {
987 	IPCL_HASH_INSERT_WILDCARD(connfp, connp);
988 }
989 
990 void
991 ipcl_proto_insert(conn_t *connp, uint8_t protocol)
992 {
993 	connf_t	*connfp;
994 	ip_stack_t	*ipst = connp->conn_netstack->netstack_ip;
995 
996 	ASSERT(connp != NULL);
997 	ASSERT(!connp->conn_mac_exempt || protocol == IPPROTO_AH ||
998 	    protocol == IPPROTO_ESP);
999 
1000 	connp->conn_ulp = protocol;
1001 
1002 	/* Insert it in the protocol hash */
1003 	connfp = &ipst->ips_ipcl_proto_fanout[protocol];
1004 	IPCL_HASH_INSERT_WILDCARD(connfp, connp);
1005 }
1006 
1007 void
1008 ipcl_proto_insert_v6(conn_t *connp, uint8_t protocol)
1009 {
1010 	connf_t	*connfp;
1011 	ip_stack_t	*ipst = connp->conn_netstack->netstack_ip;
1012 
1013 	ASSERT(connp != NULL);
1014 	ASSERT(!connp->conn_mac_exempt || protocol == IPPROTO_AH ||
1015 	    protocol == IPPROTO_ESP);
1016 
1017 	connp->conn_ulp = protocol;
1018 
1019 	/* Insert it in the Bind Hash */
1020 	connfp = &ipst->ips_ipcl_proto_fanout_v6[protocol];
1021 	IPCL_HASH_INSERT_WILDCARD(connfp, connp);
1022 }
1023 
1024 /*
1025  * This function is used only for inserting SCTP raw socket now.
1026  * This may change later.
1027  *
1028  * Note that only one raw socket can be bound to a port.  The param
1029  * lport is in network byte order.
1030  */
1031 static int
1032 ipcl_sctp_hash_insert(conn_t *connp, in_port_t lport)
1033 {
1034 	connf_t	*connfp;
1035 	conn_t	*oconnp;
1036 	ip_stack_t	*ipst = connp->conn_netstack->netstack_ip;
1037 
1038 	connfp = &ipst->ips_ipcl_raw_fanout[IPCL_RAW_HASH(ntohs(lport), ipst)];
1039 
1040 	/* Check for existing raw socket already bound to the port. */
1041 	mutex_enter(&connfp->connf_lock);
1042 	for (oconnp = connfp->connf_head; oconnp != NULL;
1043 	    oconnp = oconnp->conn_next) {
1044 		if (oconnp->conn_lport == lport &&
1045 		    oconnp->conn_zoneid == connp->conn_zoneid &&
1046 		    oconnp->conn_af_isv6 == connp->conn_af_isv6 &&
1047 		    ((IN6_IS_ADDR_UNSPECIFIED(&connp->conn_srcv6) ||
1048 		    IN6_IS_ADDR_UNSPECIFIED(&oconnp->conn_srcv6) ||
1049 		    IN6_IS_ADDR_V4MAPPED_ANY(&connp->conn_srcv6) ||
1050 		    IN6_IS_ADDR_V4MAPPED_ANY(&oconnp->conn_srcv6)) ||
1051 		    IN6_ARE_ADDR_EQUAL(&oconnp->conn_srcv6,
1052 		    &connp->conn_srcv6))) {
1053 			break;
1054 		}
1055 	}
1056 	mutex_exit(&connfp->connf_lock);
1057 	if (oconnp != NULL)
1058 		return (EADDRNOTAVAIL);
1059 
1060 	if (IN6_IS_ADDR_UNSPECIFIED(&connp->conn_remv6) ||
1061 	    IN6_IS_ADDR_V4MAPPED_ANY(&connp->conn_remv6)) {
1062 		if (IN6_IS_ADDR_UNSPECIFIED(&connp->conn_srcv6) ||
1063 		    IN6_IS_ADDR_V4MAPPED_ANY(&connp->conn_srcv6)) {
1064 			IPCL_HASH_INSERT_WILDCARD(connfp, connp);
1065 		} else {
1066 			IPCL_HASH_INSERT_BOUND(connfp, connp);
1067 		}
1068 	} else {
1069 		IPCL_HASH_INSERT_CONNECTED(connfp, connp);
1070 	}
1071 	return (0);
1072 }
1073 
1074 /*
1075  * Check for a MAC exemption conflict on a labeled system.  Note that for
1076  * protocols that use port numbers (UDP, TCP, SCTP), we do this check up in the
1077  * transport layer.  This check is for binding all other protocols.
1078  *
1079  * Returns true if there's a conflict.
1080  */
1081 static boolean_t
1082 check_exempt_conflict_v4(conn_t *connp, ip_stack_t *ipst)
1083 {
1084 	connf_t	*connfp;
1085 	conn_t *tconn;
1086 
1087 	connfp = &ipst->ips_ipcl_proto_fanout[connp->conn_ulp];
1088 	mutex_enter(&connfp->connf_lock);
1089 	for (tconn = connfp->connf_head; tconn != NULL;
1090 	    tconn = tconn->conn_next) {
1091 		/* We don't allow v4 fallback for v6 raw socket */
1092 		if (connp->conn_af_isv6 != tconn->conn_af_isv6)
1093 			continue;
1094 		/* If neither is exempt, then there's no conflict */
1095 		if (!connp->conn_mac_exempt && !tconn->conn_mac_exempt)
1096 			continue;
1097 		/* If both are bound to different specific addrs, ok */
1098 		if (connp->conn_src != INADDR_ANY &&
1099 		    tconn->conn_src != INADDR_ANY &&
1100 		    connp->conn_src != tconn->conn_src)
1101 			continue;
1102 		/* These two conflict; fail */
1103 		break;
1104 	}
1105 	mutex_exit(&connfp->connf_lock);
1106 	return (tconn != NULL);
1107 }
1108 
1109 static boolean_t
1110 check_exempt_conflict_v6(conn_t *connp, ip_stack_t *ipst)
1111 {
1112 	connf_t	*connfp;
1113 	conn_t *tconn;
1114 
1115 	connfp = &ipst->ips_ipcl_proto_fanout[connp->conn_ulp];
1116 	mutex_enter(&connfp->connf_lock);
1117 	for (tconn = connfp->connf_head; tconn != NULL;
1118 	    tconn = tconn->conn_next) {
1119 		/* We don't allow v4 fallback for v6 raw socket */
1120 		if (connp->conn_af_isv6 != tconn->conn_af_isv6)
1121 			continue;
1122 		/* If neither is exempt, then there's no conflict */
1123 		if (!connp->conn_mac_exempt && !tconn->conn_mac_exempt)
1124 			continue;
1125 		/* If both are bound to different addrs, ok */
1126 		if (!IN6_IS_ADDR_UNSPECIFIED(&connp->conn_srcv6) &&
1127 		    !IN6_IS_ADDR_UNSPECIFIED(&tconn->conn_srcv6) &&
1128 		    !IN6_ARE_ADDR_EQUAL(&connp->conn_srcv6, &tconn->conn_srcv6))
1129 			continue;
1130 		/* These two conflict; fail */
1131 		break;
1132 	}
1133 	mutex_exit(&connfp->connf_lock);
1134 	return (tconn != NULL);
1135 }
1136 
1137 /*
1138  * (v4, v6) bind hash insertion routines
1139  */
1140 int
1141 ipcl_bind_insert(conn_t *connp, uint8_t protocol, ipaddr_t src, uint16_t lport)
1142 {
1143 	connf_t	*connfp;
1144 #ifdef	IPCL_DEBUG
1145 	char	buf[INET_NTOA_BUFSIZE];
1146 #endif
1147 	int	ret = 0;
1148 	ip_stack_t	*ipst = connp->conn_netstack->netstack_ip;
1149 
1150 	ASSERT(connp);
1151 
1152 	IPCL_DEBUG_LVL(64, ("ipcl_bind_insert: connp %p, src = %s, "
1153 	    "port = %d\n", (void *)connp, inet_ntoa_r(src, buf), lport));
1154 
1155 	connp->conn_ulp = protocol;
1156 	IN6_IPADDR_TO_V4MAPPED(src, &connp->conn_srcv6);
1157 	connp->conn_lport = lport;
1158 
1159 	switch (protocol) {
1160 	default:
1161 		if (is_system_labeled() &&
1162 		    check_exempt_conflict_v4(connp, ipst))
1163 			return (EADDRINUSE);
1164 		/* FALLTHROUGH */
1165 	case IPPROTO_UDP:
1166 		if (protocol == IPPROTO_UDP) {
1167 			IPCL_DEBUG_LVL(64,
1168 			    ("ipcl_bind_insert: connp %p - udp\n",
1169 			    (void *)connp));
1170 			connfp = &ipst->ips_ipcl_udp_fanout[
1171 			    IPCL_UDP_HASH(lport, ipst)];
1172 		} else {
1173 			IPCL_DEBUG_LVL(64,
1174 			    ("ipcl_bind_insert: connp %p - protocol\n",
1175 			    (void *)connp));
1176 			connfp = &ipst->ips_ipcl_proto_fanout[protocol];
1177 		}
1178 
1179 		if (connp->conn_rem != INADDR_ANY) {
1180 			IPCL_HASH_INSERT_CONNECTED(connfp, connp);
1181 		} else if (connp->conn_src != INADDR_ANY) {
1182 			IPCL_HASH_INSERT_BOUND(connfp, connp);
1183 		} else {
1184 			IPCL_HASH_INSERT_WILDCARD(connfp, connp);
1185 		}
1186 		break;
1187 
1188 	case IPPROTO_TCP:
1189 
1190 		/* Insert it in the Bind Hash */
1191 		ASSERT(connp->conn_zoneid != ALL_ZONES);
1192 		connfp = &ipst->ips_ipcl_bind_fanout[
1193 		    IPCL_BIND_HASH(lport, ipst)];
1194 		if (connp->conn_src != INADDR_ANY) {
1195 			IPCL_HASH_INSERT_BOUND(connfp, connp);
1196 		} else {
1197 			IPCL_HASH_INSERT_WILDCARD(connfp, connp);
1198 		}
1199 		if (cl_inet_listen != NULL) {
1200 			ASSERT(!connp->conn_pkt_isv6);
1201 			connp->conn_flags |= IPCL_CL_LISTENER;
1202 			(*cl_inet_listen)(
1203 			    connp->conn_netstack->netstack_stackid,
1204 			    IPPROTO_TCP, AF_INET,
1205 			    (uint8_t *)&connp->conn_bound_source, lport, NULL);
1206 		}
1207 		break;
1208 
1209 	case IPPROTO_SCTP:
1210 		ret = ipcl_sctp_hash_insert(connp, lport);
1211 		break;
1212 	}
1213 
1214 	return (ret);
1215 }
1216 
1217 int
1218 ipcl_bind_insert_v6(conn_t *connp, uint8_t protocol, const in6_addr_t *src,
1219     uint16_t lport)
1220 {
1221 	connf_t	*connfp;
1222 	int	ret = 0;
1223 	ip_stack_t	*ipst = connp->conn_netstack->netstack_ip;
1224 
1225 	ASSERT(connp);
1226 
1227 	connp->conn_ulp = protocol;
1228 	connp->conn_srcv6 = *src;
1229 	connp->conn_lport = lport;
1230 
1231 	switch (protocol) {
1232 	default:
1233 		if (is_system_labeled() &&
1234 		    check_exempt_conflict_v6(connp, ipst))
1235 			return (EADDRINUSE);
1236 		/* FALLTHROUGH */
1237 	case IPPROTO_UDP:
1238 		if (protocol == IPPROTO_UDP) {
1239 			IPCL_DEBUG_LVL(128,
1240 			    ("ipcl_bind_insert_v6: connp %p - udp\n",
1241 			    (void *)connp));
1242 			connfp = &ipst->ips_ipcl_udp_fanout[
1243 			    IPCL_UDP_HASH(lport, ipst)];
1244 		} else {
1245 			IPCL_DEBUG_LVL(128,
1246 			    ("ipcl_bind_insert_v6: connp %p - protocol\n",
1247 			    (void *)connp));
1248 			connfp = &ipst->ips_ipcl_proto_fanout_v6[protocol];
1249 		}
1250 
1251 		if (!IN6_IS_ADDR_UNSPECIFIED(&connp->conn_remv6)) {
1252 			IPCL_HASH_INSERT_CONNECTED(connfp, connp);
1253 		} else if (!IN6_IS_ADDR_UNSPECIFIED(&connp->conn_srcv6)) {
1254 			IPCL_HASH_INSERT_BOUND(connfp, connp);
1255 		} else {
1256 			IPCL_HASH_INSERT_WILDCARD(connfp, connp);
1257 		}
1258 		break;
1259 
1260 	case IPPROTO_TCP:
1261 		/* XXX - Need a separate table for IN6_IS_ADDR_UNSPECIFIED? */
1262 
1263 		/* Insert it in the Bind Hash */
1264 		ASSERT(connp->conn_zoneid != ALL_ZONES);
1265 		connfp = &ipst->ips_ipcl_bind_fanout[
1266 		    IPCL_BIND_HASH(lport, ipst)];
1267 		if (!IN6_IS_ADDR_UNSPECIFIED(&connp->conn_srcv6)) {
1268 			IPCL_HASH_INSERT_BOUND(connfp, connp);
1269 		} else {
1270 			IPCL_HASH_INSERT_WILDCARD(connfp, connp);
1271 		}
1272 		if (cl_inet_listen != NULL) {
1273 			sa_family_t	addr_family;
1274 			uint8_t		*laddrp;
1275 
1276 			if (connp->conn_pkt_isv6) {
1277 				addr_family = AF_INET6;
1278 				laddrp =
1279 				    (uint8_t *)&connp->conn_bound_source_v6;
1280 			} else {
1281 				addr_family = AF_INET;
1282 				laddrp = (uint8_t *)&connp->conn_bound_source;
1283 			}
1284 			connp->conn_flags |= IPCL_CL_LISTENER;
1285 			(*cl_inet_listen)(
1286 			    connp->conn_netstack->netstack_stackid,
1287 			    IPPROTO_TCP, addr_family, laddrp, lport, NULL);
1288 		}
1289 		break;
1290 
1291 	case IPPROTO_SCTP:
1292 		ret = ipcl_sctp_hash_insert(connp, lport);
1293 		break;
1294 	}
1295 
1296 	return (ret);
1297 }
1298 
1299 /*
1300  * ipcl_conn_hash insertion routines.
1301  */
1302 int
1303 ipcl_conn_insert(conn_t *connp, uint8_t protocol, ipaddr_t src,
1304     ipaddr_t rem, uint32_t ports)
1305 {
1306 	connf_t		*connfp;
1307 	uint16_t	*up;
1308 	conn_t		*tconnp;
1309 #ifdef	IPCL_DEBUG
1310 	char	sbuf[INET_NTOA_BUFSIZE], rbuf[INET_NTOA_BUFSIZE];
1311 #endif
1312 	in_port_t	lport;
1313 	int		ret = 0;
1314 	ip_stack_t	*ipst = connp->conn_netstack->netstack_ip;
1315 
1316 	IPCL_DEBUG_LVL(256, ("ipcl_conn_insert: connp %p, src = %s, "
1317 	    "dst = %s, ports = %x, protocol = %x", (void *)connp,
1318 	    inet_ntoa_r(src, sbuf), inet_ntoa_r(rem, rbuf),
1319 	    ports, protocol));
1320 
1321 	switch (protocol) {
1322 	case IPPROTO_TCP:
1323 		if (!(connp->conn_flags & IPCL_EAGER)) {
1324 			/*
1325 			 * for a eager connection, i.e connections which
1326 			 * have just been created, the initialization is
1327 			 * already done in ip at conn_creation time, so
1328 			 * we can skip the checks here.
1329 			 */
1330 			IPCL_CONN_INIT(connp, protocol, src, rem, ports);
1331 		}
1332 
1333 		/*
1334 		 * For tcp, we check whether the connection tuple already
1335 		 * exists before allowing the connection to proceed.  We
1336 		 * also allow indexing on the zoneid. This is to allow
1337 		 * multiple shared stack zones to have the same tcp
1338 		 * connection tuple. In practice this only happens for
1339 		 * INADDR_LOOPBACK as it's the only local address which
1340 		 * doesn't have to be unique.
1341 		 */
1342 		connfp = &ipst->ips_ipcl_conn_fanout[
1343 		    IPCL_CONN_HASH(connp->conn_rem,
1344 		    connp->conn_ports, ipst)];
1345 		mutex_enter(&connfp->connf_lock);
1346 		for (tconnp = connfp->connf_head; tconnp != NULL;
1347 		    tconnp = tconnp->conn_next) {
1348 			if ((IPCL_CONN_MATCH(tconnp, connp->conn_ulp,
1349 			    connp->conn_rem, connp->conn_src,
1350 			    connp->conn_ports)) &&
1351 			    (IPCL_ZONE_MATCH(tconnp, connp->conn_zoneid))) {
1352 
1353 				/* Already have a conn. bail out */
1354 				mutex_exit(&connfp->connf_lock);
1355 				return (EADDRINUSE);
1356 			}
1357 		}
1358 		if (connp->conn_fanout != NULL) {
1359 			/*
1360 			 * Probably a XTI/TLI application trying to do a
1361 			 * rebind. Let it happen.
1362 			 */
1363 			mutex_exit(&connfp->connf_lock);
1364 			IPCL_HASH_REMOVE(connp);
1365 			mutex_enter(&connfp->connf_lock);
1366 		}
1367 
1368 		ASSERT(connp->conn_recv != NULL);
1369 
1370 		IPCL_HASH_INSERT_CONNECTED_LOCKED(connfp, connp);
1371 		mutex_exit(&connfp->connf_lock);
1372 		break;
1373 
1374 	case IPPROTO_SCTP:
1375 		/*
1376 		 * The raw socket may have already been bound, remove it
1377 		 * from the hash first.
1378 		 */
1379 		IPCL_HASH_REMOVE(connp);
1380 		lport = htons((uint16_t)(ntohl(ports) & 0xFFFF));
1381 		ret = ipcl_sctp_hash_insert(connp, lport);
1382 		break;
1383 
1384 	default:
1385 		/*
1386 		 * Check for conflicts among MAC exempt bindings.  For
1387 		 * transports with port numbers, this is done by the upper
1388 		 * level per-transport binding logic.  For all others, it's
1389 		 * done here.
1390 		 */
1391 		if (is_system_labeled() &&
1392 		    check_exempt_conflict_v4(connp, ipst))
1393 			return (EADDRINUSE);
1394 		/* FALLTHROUGH */
1395 
1396 	case IPPROTO_UDP:
1397 		up = (uint16_t *)&ports;
1398 		IPCL_CONN_INIT(connp, protocol, src, rem, ports);
1399 		if (protocol == IPPROTO_UDP) {
1400 			connfp = &ipst->ips_ipcl_udp_fanout[
1401 			    IPCL_UDP_HASH(up[1], ipst)];
1402 		} else {
1403 			connfp = &ipst->ips_ipcl_proto_fanout[protocol];
1404 		}
1405 
1406 		if (connp->conn_rem != INADDR_ANY) {
1407 			IPCL_HASH_INSERT_CONNECTED(connfp, connp);
1408 		} else if (connp->conn_src != INADDR_ANY) {
1409 			IPCL_HASH_INSERT_BOUND(connfp, connp);
1410 		} else {
1411 			IPCL_HASH_INSERT_WILDCARD(connfp, connp);
1412 		}
1413 		break;
1414 	}
1415 
1416 	return (ret);
1417 }
1418 
1419 int
1420 ipcl_conn_insert_v6(conn_t *connp, uint8_t protocol, const in6_addr_t *src,
1421     const in6_addr_t *rem, uint32_t ports, uint_t ifindex)
1422 {
1423 	connf_t		*connfp;
1424 	uint16_t	*up;
1425 	conn_t		*tconnp;
1426 	in_port_t	lport;
1427 	int		ret = 0;
1428 	ip_stack_t	*ipst = connp->conn_netstack->netstack_ip;
1429 
1430 	switch (protocol) {
1431 	case IPPROTO_TCP:
1432 		/* Just need to insert a conn struct */
1433 		if (!(connp->conn_flags & IPCL_EAGER)) {
1434 			IPCL_CONN_INIT_V6(connp, protocol, *src, *rem, ports);
1435 		}
1436 
1437 		/*
1438 		 * For tcp, we check whether the connection tuple already
1439 		 * exists before allowing the connection to proceed.  We
1440 		 * also allow indexing on the zoneid. This is to allow
1441 		 * multiple shared stack zones to have the same tcp
1442 		 * connection tuple. In practice this only happens for
1443 		 * ipv6_loopback as it's the only local address which
1444 		 * doesn't have to be unique.
1445 		 */
1446 		connfp = &ipst->ips_ipcl_conn_fanout[
1447 		    IPCL_CONN_HASH_V6(connp->conn_remv6, connp->conn_ports,
1448 		    ipst)];
1449 		mutex_enter(&connfp->connf_lock);
1450 		for (tconnp = connfp->connf_head; tconnp != NULL;
1451 		    tconnp = tconnp->conn_next) {
1452 			if (IPCL_CONN_MATCH_V6(tconnp, connp->conn_ulp,
1453 			    connp->conn_remv6, connp->conn_srcv6,
1454 			    connp->conn_ports) &&
1455 			    (tconnp->conn_tcp->tcp_bound_if == 0 ||
1456 			    tconnp->conn_tcp->tcp_bound_if == ifindex) &&
1457 			    (IPCL_ZONE_MATCH(tconnp, connp->conn_zoneid))) {
1458 				/* Already have a conn. bail out */
1459 				mutex_exit(&connfp->connf_lock);
1460 				return (EADDRINUSE);
1461 			}
1462 		}
1463 		if (connp->conn_fanout != NULL) {
1464 			/*
1465 			 * Probably a XTI/TLI application trying to do a
1466 			 * rebind. Let it happen.
1467 			 */
1468 			mutex_exit(&connfp->connf_lock);
1469 			IPCL_HASH_REMOVE(connp);
1470 			mutex_enter(&connfp->connf_lock);
1471 		}
1472 		IPCL_HASH_INSERT_CONNECTED_LOCKED(connfp, connp);
1473 		mutex_exit(&connfp->connf_lock);
1474 		break;
1475 
1476 	case IPPROTO_SCTP:
1477 		IPCL_HASH_REMOVE(connp);
1478 		lport = htons((uint16_t)(ntohl(ports) & 0xFFFF));
1479 		ret = ipcl_sctp_hash_insert(connp, lport);
1480 		break;
1481 
1482 	default:
1483 		if (is_system_labeled() &&
1484 		    check_exempt_conflict_v6(connp, ipst))
1485 			return (EADDRINUSE);
1486 		/* FALLTHROUGH */
1487 	case IPPROTO_UDP:
1488 		up = (uint16_t *)&ports;
1489 		IPCL_CONN_INIT_V6(connp, protocol, *src, *rem, ports);
1490 		if (protocol == IPPROTO_UDP) {
1491 			connfp = &ipst->ips_ipcl_udp_fanout[
1492 			    IPCL_UDP_HASH(up[1], ipst)];
1493 		} else {
1494 			connfp = &ipst->ips_ipcl_proto_fanout_v6[protocol];
1495 		}
1496 
1497 		if (!IN6_IS_ADDR_UNSPECIFIED(&connp->conn_remv6)) {
1498 			IPCL_HASH_INSERT_CONNECTED(connfp, connp);
1499 		} else if (!IN6_IS_ADDR_UNSPECIFIED(&connp->conn_srcv6)) {
1500 			IPCL_HASH_INSERT_BOUND(connfp, connp);
1501 		} else {
1502 			IPCL_HASH_INSERT_WILDCARD(connfp, connp);
1503 		}
1504 		break;
1505 	}
1506 
1507 	return (ret);
1508 }
1509 
1510 /*
1511  * v4 packet classifying function. looks up the fanout table to
1512  * find the conn, the packet belongs to. returns the conn with
1513  * the reference held, null otherwise.
1514  *
1515  * If zoneid is ALL_ZONES, then the search rules described in the "Connection
1516  * Lookup" comment block are applied.  Labels are also checked as described
1517  * above.  If the packet is from the inside (looped back), and is from the same
1518  * zone, then label checks are omitted.
1519  */
1520 conn_t *
1521 ipcl_classify_v4(mblk_t *mp, uint8_t protocol, uint_t hdr_len, zoneid_t zoneid,
1522     ip_stack_t *ipst)
1523 {
1524 	ipha_t	*ipha;
1525 	connf_t	*connfp, *bind_connfp;
1526 	uint16_t lport;
1527 	uint16_t fport;
1528 	uint32_t ports;
1529 	conn_t	*connp;
1530 	uint16_t  *up;
1531 	boolean_t shared_addr;
1532 	boolean_t unlabeled;
1533 
1534 	ipha = (ipha_t *)mp->b_rptr;
1535 	up = (uint16_t *)((uchar_t *)ipha + hdr_len + TCP_PORTS_OFFSET);
1536 
1537 	switch (protocol) {
1538 	case IPPROTO_TCP:
1539 		ports = *(uint32_t *)up;
1540 		connfp =
1541 		    &ipst->ips_ipcl_conn_fanout[IPCL_CONN_HASH(ipha->ipha_src,
1542 		    ports, ipst)];
1543 		mutex_enter(&connfp->connf_lock);
1544 		for (connp = connfp->connf_head; connp != NULL;
1545 		    connp = connp->conn_next) {
1546 			if ((IPCL_CONN_MATCH(connp, protocol,
1547 			    ipha->ipha_src, ipha->ipha_dst, ports)) &&
1548 			    (IPCL_ZONE_MATCH(connp, zoneid))) {
1549 				break;
1550 			}
1551 		}
1552 
1553 		if (connp != NULL) {
1554 			/*
1555 			 * We have a fully-bound TCP connection.
1556 			 *
1557 			 * For labeled systems, there's no need to check the
1558 			 * label here.  It's known to be good as we checked
1559 			 * before allowing the connection to become bound.
1560 			 */
1561 			CONN_INC_REF(connp);
1562 			mutex_exit(&connfp->connf_lock);
1563 			return (connp);
1564 		}
1565 
1566 		mutex_exit(&connfp->connf_lock);
1567 
1568 		lport = up[1];
1569 		unlabeled = B_FALSE;
1570 		/* Cred cannot be null on IPv4 */
1571 		if (is_system_labeled()) {
1572 			cred_t *cr = msg_getcred(mp, NULL);
1573 			ASSERT(cr != NULL);
1574 			unlabeled = (crgetlabel(cr)->tsl_flags &
1575 			    TSLF_UNLABELED) != 0;
1576 		}
1577 		shared_addr = (zoneid == ALL_ZONES);
1578 		if (shared_addr) {
1579 			/*
1580 			 * No need to handle exclusive-stack zones since
1581 			 * ALL_ZONES only applies to the shared stack.
1582 			 */
1583 			zoneid = tsol_mlp_findzone(protocol, lport);
1584 			/*
1585 			 * If no shared MLP is found, tsol_mlp_findzone returns
1586 			 * ALL_ZONES.  In that case, we assume it's SLP, and
1587 			 * search for the zone based on the packet label.
1588 			 *
1589 			 * If there is such a zone, we prefer to find a
1590 			 * connection in it.  Otherwise, we look for a
1591 			 * MAC-exempt connection in any zone whose label
1592 			 * dominates the default label on the packet.
1593 			 */
1594 			if (zoneid == ALL_ZONES)
1595 				zoneid = tsol_packet_to_zoneid(mp);
1596 			else
1597 				unlabeled = B_FALSE;
1598 		}
1599 
1600 		bind_connfp =
1601 		    &ipst->ips_ipcl_bind_fanout[IPCL_BIND_HASH(lport, ipst)];
1602 		mutex_enter(&bind_connfp->connf_lock);
1603 		for (connp = bind_connfp->connf_head; connp != NULL;
1604 		    connp = connp->conn_next) {
1605 			if (IPCL_BIND_MATCH(connp, protocol, ipha->ipha_dst,
1606 			    lport) && (IPCL_ZONE_MATCH(connp, zoneid) ||
1607 			    (unlabeled && connp->conn_mac_exempt)))
1608 				break;
1609 		}
1610 
1611 		/*
1612 		 * If the matching connection is SLP on a private address, then
1613 		 * the label on the packet must match the local zone's label.
1614 		 * Otherwise, it must be in the label range defined by tnrh.
1615 		 * This is ensured by tsol_receive_label.
1616 		 */
1617 		if (connp != NULL && is_system_labeled() &&
1618 		    !tsol_receive_local(mp, &ipha->ipha_dst, IPV4_VERSION,
1619 		    shared_addr, connp)) {
1620 				DTRACE_PROBE3(
1621 				    tx__ip__log__info__classify__tcp,
1622 				    char *,
1623 				    "connp(1) could not receive mp(2)",
1624 				    conn_t *, connp, mblk_t *, mp);
1625 			connp = NULL;
1626 		}
1627 
1628 		if (connp != NULL) {
1629 			/* Have a listener at least */
1630 			CONN_INC_REF(connp);
1631 			mutex_exit(&bind_connfp->connf_lock);
1632 			return (connp);
1633 		}
1634 
1635 		mutex_exit(&bind_connfp->connf_lock);
1636 
1637 		IPCL_DEBUG_LVL(512,
1638 		    ("ipcl_classify: couldn't classify mp = %p\n",
1639 		    (void *)mp));
1640 		break;
1641 
1642 	case IPPROTO_UDP:
1643 		lport = up[1];
1644 		unlabeled = B_FALSE;
1645 		/* Cred cannot be null on IPv4 */
1646 		if (is_system_labeled()) {
1647 			cred_t *cr = msg_getcred(mp, NULL);
1648 			ASSERT(cr != NULL);
1649 			unlabeled = (crgetlabel(cr)->tsl_flags &
1650 			    TSLF_UNLABELED) != 0;
1651 		}
1652 		shared_addr = (zoneid == ALL_ZONES);
1653 		if (shared_addr) {
1654 			/*
1655 			 * No need to handle exclusive-stack zones since
1656 			 * ALL_ZONES only applies to the shared stack.
1657 			 */
1658 			zoneid = tsol_mlp_findzone(protocol, lport);
1659 			/*
1660 			 * If no shared MLP is found, tsol_mlp_findzone returns
1661 			 * ALL_ZONES.  In that case, we assume it's SLP, and
1662 			 * search for the zone based on the packet label.
1663 			 *
1664 			 * If there is such a zone, we prefer to find a
1665 			 * connection in it.  Otherwise, we look for a
1666 			 * MAC-exempt connection in any zone whose label
1667 			 * dominates the default label on the packet.
1668 			 */
1669 			if (zoneid == ALL_ZONES)
1670 				zoneid = tsol_packet_to_zoneid(mp);
1671 			else
1672 				unlabeled = B_FALSE;
1673 		}
1674 		fport = up[0];
1675 		IPCL_DEBUG_LVL(512, ("ipcl_udp_classify %x %x", lport, fport));
1676 		connfp = &ipst->ips_ipcl_udp_fanout[IPCL_UDP_HASH(lport, ipst)];
1677 		mutex_enter(&connfp->connf_lock);
1678 		for (connp = connfp->connf_head; connp != NULL;
1679 		    connp = connp->conn_next) {
1680 			if (IPCL_UDP_MATCH(connp, lport, ipha->ipha_dst,
1681 			    fport, ipha->ipha_src) &&
1682 			    (IPCL_ZONE_MATCH(connp, zoneid) ||
1683 			    (unlabeled && connp->conn_mac_exempt)))
1684 				break;
1685 		}
1686 
1687 		if (connp != NULL && is_system_labeled() &&
1688 		    !tsol_receive_local(mp, &ipha->ipha_dst, IPV4_VERSION,
1689 		    shared_addr, connp)) {
1690 			DTRACE_PROBE3(tx__ip__log__info__classify__udp,
1691 			    char *, "connp(1) could not receive mp(2)",
1692 			    conn_t *, connp, mblk_t *, mp);
1693 			connp = NULL;
1694 		}
1695 
1696 		if (connp != NULL) {
1697 			CONN_INC_REF(connp);
1698 			mutex_exit(&connfp->connf_lock);
1699 			return (connp);
1700 		}
1701 
1702 		/*
1703 		 * We shouldn't come here for multicast/broadcast packets
1704 		 */
1705 		mutex_exit(&connfp->connf_lock);
1706 		IPCL_DEBUG_LVL(512,
1707 		    ("ipcl_classify: cant find udp conn_t for ports : %x %x",
1708 		    lport, fport));
1709 		break;
1710 	}
1711 
1712 	return (NULL);
1713 }
1714 
1715 conn_t *
1716 ipcl_classify_v6(mblk_t *mp, uint8_t protocol, uint_t hdr_len, zoneid_t zoneid,
1717     ip_stack_t *ipst)
1718 {
1719 	ip6_t		*ip6h;
1720 	connf_t		*connfp, *bind_connfp;
1721 	uint16_t	lport;
1722 	uint16_t	fport;
1723 	tcph_t		*tcph;
1724 	uint32_t	ports;
1725 	conn_t		*connp;
1726 	uint16_t	*up;
1727 	boolean_t	shared_addr;
1728 	boolean_t	unlabeled;
1729 
1730 	ip6h = (ip6_t *)mp->b_rptr;
1731 
1732 	switch (protocol) {
1733 	case IPPROTO_TCP:
1734 		tcph = (tcph_t *)&mp->b_rptr[hdr_len];
1735 		up = (uint16_t *)tcph->th_lport;
1736 		ports = *(uint32_t *)up;
1737 
1738 		connfp =
1739 		    &ipst->ips_ipcl_conn_fanout[IPCL_CONN_HASH_V6(ip6h->ip6_src,
1740 		    ports, ipst)];
1741 		mutex_enter(&connfp->connf_lock);
1742 		for (connp = connfp->connf_head; connp != NULL;
1743 		    connp = connp->conn_next) {
1744 			if ((IPCL_CONN_MATCH_V6(connp, protocol,
1745 			    ip6h->ip6_src, ip6h->ip6_dst, ports)) &&
1746 			    (IPCL_ZONE_MATCH(connp, zoneid))) {
1747 				break;
1748 			}
1749 		}
1750 
1751 		if (connp != NULL) {
1752 			/*
1753 			 * We have a fully-bound TCP connection.
1754 			 *
1755 			 * For labeled systems, there's no need to check the
1756 			 * label here.  It's known to be good as we checked
1757 			 * before allowing the connection to become bound.
1758 			 */
1759 			CONN_INC_REF(connp);
1760 			mutex_exit(&connfp->connf_lock);
1761 			return (connp);
1762 		}
1763 
1764 		mutex_exit(&connfp->connf_lock);
1765 
1766 		lport = up[1];
1767 		unlabeled = B_FALSE;
1768 		/* Cred can be null on IPv6 */
1769 		if (is_system_labeled()) {
1770 			cred_t *cr = msg_getcred(mp, NULL);
1771 
1772 			unlabeled = (cr != NULL &&
1773 			    crgetlabel(cr)->tsl_flags & TSLF_UNLABELED) != 0;
1774 		}
1775 		shared_addr = (zoneid == ALL_ZONES);
1776 		if (shared_addr) {
1777 			/*
1778 			 * No need to handle exclusive-stack zones since
1779 			 * ALL_ZONES only applies to the shared stack.
1780 			 */
1781 			zoneid = tsol_mlp_findzone(protocol, lport);
1782 			/*
1783 			 * If no shared MLP is found, tsol_mlp_findzone returns
1784 			 * ALL_ZONES.  In that case, we assume it's SLP, and
1785 			 * search for the zone based on the packet label.
1786 			 *
1787 			 * If there is such a zone, we prefer to find a
1788 			 * connection in it.  Otherwise, we look for a
1789 			 * MAC-exempt connection in any zone whose label
1790 			 * dominates the default label on the packet.
1791 			 */
1792 			if (zoneid == ALL_ZONES)
1793 				zoneid = tsol_packet_to_zoneid(mp);
1794 			else
1795 				unlabeled = B_FALSE;
1796 		}
1797 
1798 		bind_connfp =
1799 		    &ipst->ips_ipcl_bind_fanout[IPCL_BIND_HASH(lport, ipst)];
1800 		mutex_enter(&bind_connfp->connf_lock);
1801 		for (connp = bind_connfp->connf_head; connp != NULL;
1802 		    connp = connp->conn_next) {
1803 			if (IPCL_BIND_MATCH_V6(connp, protocol,
1804 			    ip6h->ip6_dst, lport) &&
1805 			    (IPCL_ZONE_MATCH(connp, zoneid) ||
1806 			    (unlabeled && connp->conn_mac_exempt)))
1807 				break;
1808 		}
1809 
1810 		if (connp != NULL && is_system_labeled() &&
1811 		    !tsol_receive_local(mp, &ip6h->ip6_dst, IPV6_VERSION,
1812 		    shared_addr, connp)) {
1813 			DTRACE_PROBE3(tx__ip__log__info__classify__tcp6,
1814 			    char *, "connp(1) could not receive mp(2)",
1815 			    conn_t *, connp, mblk_t *, mp);
1816 			connp = NULL;
1817 		}
1818 
1819 		if (connp != NULL) {
1820 			/* Have a listner at least */
1821 			CONN_INC_REF(connp);
1822 			mutex_exit(&bind_connfp->connf_lock);
1823 			IPCL_DEBUG_LVL(512,
1824 			    ("ipcl_classify_v6: found listner "
1825 			    "connp = %p\n", (void *)connp));
1826 
1827 			return (connp);
1828 		}
1829 
1830 		mutex_exit(&bind_connfp->connf_lock);
1831 
1832 		IPCL_DEBUG_LVL(512,
1833 		    ("ipcl_classify_v6: couldn't classify mp = %p\n",
1834 		    (void *)mp));
1835 		break;
1836 
1837 	case IPPROTO_UDP:
1838 		up = (uint16_t *)&mp->b_rptr[hdr_len];
1839 		lport = up[1];
1840 		unlabeled = B_FALSE;
1841 		/* Cred can be null on IPv6 */
1842 		if (is_system_labeled()) {
1843 			cred_t *cr = msg_getcred(mp, NULL);
1844 
1845 			unlabeled = (cr != NULL &&
1846 			    crgetlabel(cr)->tsl_flags & TSLF_UNLABELED) != 0;
1847 		}
1848 		shared_addr = (zoneid == ALL_ZONES);
1849 		if (shared_addr) {
1850 			/*
1851 			 * No need to handle exclusive-stack zones since
1852 			 * ALL_ZONES only applies to the shared stack.
1853 			 */
1854 			zoneid = tsol_mlp_findzone(protocol, lport);
1855 			/*
1856 			 * If no shared MLP is found, tsol_mlp_findzone returns
1857 			 * ALL_ZONES.  In that case, we assume it's SLP, and
1858 			 * search for the zone based on the packet label.
1859 			 *
1860 			 * If there is such a zone, we prefer to find a
1861 			 * connection in it.  Otherwise, we look for a
1862 			 * MAC-exempt connection in any zone whose label
1863 			 * dominates the default label on the packet.
1864 			 */
1865 			if (zoneid == ALL_ZONES)
1866 				zoneid = tsol_packet_to_zoneid(mp);
1867 			else
1868 				unlabeled = B_FALSE;
1869 		}
1870 
1871 		fport = up[0];
1872 		IPCL_DEBUG_LVL(512, ("ipcl_udp_classify_v6 %x %x", lport,
1873 		    fport));
1874 		connfp = &ipst->ips_ipcl_udp_fanout[IPCL_UDP_HASH(lport, ipst)];
1875 		mutex_enter(&connfp->connf_lock);
1876 		for (connp = connfp->connf_head; connp != NULL;
1877 		    connp = connp->conn_next) {
1878 			if (IPCL_UDP_MATCH_V6(connp, lport, ip6h->ip6_dst,
1879 			    fport, ip6h->ip6_src) &&
1880 			    (IPCL_ZONE_MATCH(connp, zoneid) ||
1881 			    (unlabeled && connp->conn_mac_exempt)))
1882 				break;
1883 		}
1884 
1885 		if (connp != NULL && is_system_labeled() &&
1886 		    !tsol_receive_local(mp, &ip6h->ip6_dst, IPV6_VERSION,
1887 		    shared_addr, connp)) {
1888 			DTRACE_PROBE3(tx__ip__log__info__classify__udp6,
1889 			    char *, "connp(1) could not receive mp(2)",
1890 			    conn_t *, connp, mblk_t *, mp);
1891 			connp = NULL;
1892 		}
1893 
1894 		if (connp != NULL) {
1895 			CONN_INC_REF(connp);
1896 			mutex_exit(&connfp->connf_lock);
1897 			return (connp);
1898 		}
1899 
1900 		/*
1901 		 * We shouldn't come here for multicast/broadcast packets
1902 		 */
1903 		mutex_exit(&connfp->connf_lock);
1904 		IPCL_DEBUG_LVL(512,
1905 		    ("ipcl_classify_v6: cant find udp conn_t for ports : %x %x",
1906 		    lport, fport));
1907 		break;
1908 	}
1909 
1910 	return (NULL);
1911 }
1912 
1913 /*
1914  * wrapper around ipcl_classify_(v4,v6) routines.
1915  */
1916 conn_t *
1917 ipcl_classify(mblk_t *mp, zoneid_t zoneid, ip_stack_t *ipst)
1918 {
1919 	uint16_t	hdr_len;
1920 	ipha_t		*ipha;
1921 	uint8_t		*nexthdrp;
1922 
1923 	if (MBLKL(mp) < sizeof (ipha_t))
1924 		return (NULL);
1925 
1926 	switch (IPH_HDR_VERSION(mp->b_rptr)) {
1927 	case IPV4_VERSION:
1928 		ipha = (ipha_t *)mp->b_rptr;
1929 		hdr_len = IPH_HDR_LENGTH(ipha);
1930 		return (ipcl_classify_v4(mp, ipha->ipha_protocol, hdr_len,
1931 		    zoneid, ipst));
1932 	case IPV6_VERSION:
1933 		if (!ip_hdr_length_nexthdr_v6(mp, (ip6_t *)mp->b_rptr,
1934 		    &hdr_len, &nexthdrp))
1935 			return (NULL);
1936 
1937 		return (ipcl_classify_v6(mp, *nexthdrp, hdr_len, zoneid, ipst));
1938 	}
1939 
1940 	return (NULL);
1941 }
1942 
1943 conn_t *
1944 ipcl_classify_raw(mblk_t *mp, uint8_t protocol, zoneid_t zoneid,
1945     uint32_t ports, ipha_t *hdr, ip_stack_t *ipst)
1946 {
1947 	connf_t		*connfp;
1948 	conn_t		*connp;
1949 	in_port_t	lport;
1950 	int		af;
1951 	boolean_t	shared_addr;
1952 	boolean_t	unlabeled;
1953 	const void	*dst;
1954 
1955 	lport = ((uint16_t *)&ports)[1];
1956 
1957 	unlabeled = B_FALSE;
1958 	/* Cred can be null on IPv6 */
1959 	if (is_system_labeled()) {
1960 		cred_t *cr = msg_getcred(mp, NULL);
1961 
1962 		unlabeled = (cr != NULL &&
1963 		    crgetlabel(cr)->tsl_flags & TSLF_UNLABELED) != 0;
1964 	}
1965 	shared_addr = (zoneid == ALL_ZONES);
1966 	if (shared_addr) {
1967 		/*
1968 		 * No need to handle exclusive-stack zones since ALL_ZONES
1969 		 * only applies to the shared stack.
1970 		 */
1971 		zoneid = tsol_mlp_findzone(protocol, lport);
1972 		/*
1973 		 * If no shared MLP is found, tsol_mlp_findzone returns
1974 		 * ALL_ZONES.  In that case, we assume it's SLP, and search for
1975 		 * the zone based on the packet label.
1976 		 *
1977 		 * If there is such a zone, we prefer to find a connection in
1978 		 * it.  Otherwise, we look for a MAC-exempt connection in any
1979 		 * zone whose label dominates the default label on the packet.
1980 		 */
1981 		if (zoneid == ALL_ZONES)
1982 			zoneid = tsol_packet_to_zoneid(mp);
1983 		else
1984 			unlabeled = B_FALSE;
1985 	}
1986 
1987 	af = IPH_HDR_VERSION(hdr);
1988 	dst = af == IPV4_VERSION ? (const void *)&hdr->ipha_dst :
1989 	    (const void *)&((ip6_t *)hdr)->ip6_dst;
1990 	connfp = &ipst->ips_ipcl_raw_fanout[IPCL_RAW_HASH(ntohs(lport), ipst)];
1991 
1992 	mutex_enter(&connfp->connf_lock);
1993 	for (connp = connfp->connf_head; connp != NULL;
1994 	    connp = connp->conn_next) {
1995 		/* We don't allow v4 fallback for v6 raw socket. */
1996 		if (af == (connp->conn_af_isv6 ? IPV4_VERSION :
1997 		    IPV6_VERSION))
1998 			continue;
1999 		if (connp->conn_fully_bound) {
2000 			if (af == IPV4_VERSION) {
2001 				if (!IPCL_CONN_MATCH(connp, protocol,
2002 				    hdr->ipha_src, hdr->ipha_dst, ports))
2003 					continue;
2004 			} else {
2005 				if (!IPCL_CONN_MATCH_V6(connp, protocol,
2006 				    ((ip6_t *)hdr)->ip6_src,
2007 				    ((ip6_t *)hdr)->ip6_dst, ports))
2008 					continue;
2009 			}
2010 		} else {
2011 			if (af == IPV4_VERSION) {
2012 				if (!IPCL_BIND_MATCH(connp, protocol,
2013 				    hdr->ipha_dst, lport))
2014 					continue;
2015 			} else {
2016 				if (!IPCL_BIND_MATCH_V6(connp, protocol,
2017 				    ((ip6_t *)hdr)->ip6_dst, lport))
2018 					continue;
2019 			}
2020 		}
2021 
2022 		if (IPCL_ZONE_MATCH(connp, zoneid) ||
2023 		    (unlabeled && connp->conn_mac_exempt))
2024 			break;
2025 	}
2026 	/*
2027 	 * If the connection is fully-bound and connection-oriented (TCP or
2028 	 * SCTP), then we've already validated the remote system's label.
2029 	 * There's no need to do it again for every packet.
2030 	 */
2031 	if (connp != NULL && is_system_labeled() && (!connp->conn_fully_bound ||
2032 	    !(connp->conn_flags & (IPCL_TCP|IPCL_SCTPCONN))) &&
2033 	    !tsol_receive_local(mp, dst, af, shared_addr, connp)) {
2034 		DTRACE_PROBE3(tx__ip__log__info__classify__rawip,
2035 		    char *, "connp(1) could not receive mp(2)",
2036 		    conn_t *, connp, mblk_t *, mp);
2037 		connp = NULL;
2038 	}
2039 
2040 	if (connp != NULL)
2041 		goto found;
2042 	mutex_exit(&connfp->connf_lock);
2043 
2044 	/* Try to look for a wildcard match. */
2045 	connfp = &ipst->ips_ipcl_raw_fanout[IPCL_RAW_HASH(0, ipst)];
2046 	mutex_enter(&connfp->connf_lock);
2047 	for (connp = connfp->connf_head; connp != NULL;
2048 	    connp = connp->conn_next) {
2049 		/* We don't allow v4 fallback for v6 raw socket. */
2050 		if ((af == (connp->conn_af_isv6 ? IPV4_VERSION :
2051 		    IPV6_VERSION)) || !IPCL_ZONE_MATCH(connp, zoneid)) {
2052 			continue;
2053 		}
2054 		if (af == IPV4_VERSION) {
2055 			if (IPCL_RAW_MATCH(connp, protocol, hdr->ipha_dst))
2056 				break;
2057 		} else {
2058 			if (IPCL_RAW_MATCH_V6(connp, protocol,
2059 			    ((ip6_t *)hdr)->ip6_dst)) {
2060 				break;
2061 			}
2062 		}
2063 	}
2064 
2065 	if (connp != NULL)
2066 		goto found;
2067 
2068 	mutex_exit(&connfp->connf_lock);
2069 	return (NULL);
2070 
2071 found:
2072 	ASSERT(connp != NULL);
2073 	CONN_INC_REF(connp);
2074 	mutex_exit(&connfp->connf_lock);
2075 	return (connp);
2076 }
2077 
2078 /* ARGSUSED */
2079 static int
2080 tcp_conn_constructor(void *buf, void *cdrarg, int kmflags)
2081 {
2082 	itc_t	*itc = (itc_t *)buf;
2083 	conn_t 	*connp = &itc->itc_conn;
2084 	tcp_t	*tcp = (tcp_t *)&itc[1];
2085 
2086 	bzero(connp, sizeof (conn_t));
2087 	bzero(tcp, sizeof (tcp_t));
2088 
2089 	mutex_init(&connp->conn_lock, NULL, MUTEX_DEFAULT, NULL);
2090 	cv_init(&connp->conn_cv, NULL, CV_DEFAULT, NULL);
2091 	cv_init(&connp->conn_sq_cv, NULL, CV_DEFAULT, NULL);
2092 	tcp->tcp_timercache = tcp_timermp_alloc(KM_NOSLEEP);
2093 	connp->conn_tcp = tcp;
2094 	connp->conn_flags = IPCL_TCPCONN;
2095 	connp->conn_ulp = IPPROTO_TCP;
2096 	tcp->tcp_connp = connp;
2097 	return (0);
2098 }
2099 
2100 /* ARGSUSED */
2101 static void
2102 tcp_conn_destructor(void *buf, void *cdrarg)
2103 {
2104 	itc_t	*itc = (itc_t *)buf;
2105 	conn_t 	*connp = &itc->itc_conn;
2106 	tcp_t	*tcp = (tcp_t *)&itc[1];
2107 
2108 	ASSERT(connp->conn_flags & IPCL_TCPCONN);
2109 	ASSERT(tcp->tcp_connp == connp);
2110 	ASSERT(connp->conn_tcp == tcp);
2111 	tcp_timermp_free(tcp);
2112 	mutex_destroy(&connp->conn_lock);
2113 	cv_destroy(&connp->conn_cv);
2114 	cv_destroy(&connp->conn_sq_cv);
2115 }
2116 
2117 /* ARGSUSED */
2118 static int
2119 ip_conn_constructor(void *buf, void *cdrarg, int kmflags)
2120 {
2121 	itc_t	*itc = (itc_t *)buf;
2122 	conn_t 	*connp = &itc->itc_conn;
2123 
2124 	bzero(connp, sizeof (conn_t));
2125 	mutex_init(&connp->conn_lock, NULL, MUTEX_DEFAULT, NULL);
2126 	cv_init(&connp->conn_cv, NULL, CV_DEFAULT, NULL);
2127 	connp->conn_flags = IPCL_IPCCONN;
2128 
2129 	return (0);
2130 }
2131 
2132 /* ARGSUSED */
2133 static void
2134 ip_conn_destructor(void *buf, void *cdrarg)
2135 {
2136 	itc_t	*itc = (itc_t *)buf;
2137 	conn_t 	*connp = &itc->itc_conn;
2138 
2139 	ASSERT(connp->conn_flags & IPCL_IPCCONN);
2140 	ASSERT(connp->conn_priv == NULL);
2141 	mutex_destroy(&connp->conn_lock);
2142 	cv_destroy(&connp->conn_cv);
2143 }
2144 
2145 /* ARGSUSED */
2146 static int
2147 udp_conn_constructor(void *buf, void *cdrarg, int kmflags)
2148 {
2149 	itc_t	*itc = (itc_t *)buf;
2150 	conn_t 	*connp = &itc->itc_conn;
2151 	udp_t	*udp = (udp_t *)&itc[1];
2152 
2153 	bzero(connp, sizeof (conn_t));
2154 	bzero(udp, sizeof (udp_t));
2155 
2156 	mutex_init(&connp->conn_lock, NULL, MUTEX_DEFAULT, NULL);
2157 	cv_init(&connp->conn_cv, NULL, CV_DEFAULT, NULL);
2158 	connp->conn_udp = udp;
2159 	connp->conn_flags = IPCL_UDPCONN;
2160 	connp->conn_ulp = IPPROTO_UDP;
2161 	udp->udp_connp = connp;
2162 	return (0);
2163 }
2164 
2165 /* ARGSUSED */
2166 static void
2167 udp_conn_destructor(void *buf, void *cdrarg)
2168 {
2169 	itc_t	*itc = (itc_t *)buf;
2170 	conn_t 	*connp = &itc->itc_conn;
2171 	udp_t	*udp = (udp_t *)&itc[1];
2172 
2173 	ASSERT(connp->conn_flags & IPCL_UDPCONN);
2174 	ASSERT(udp->udp_connp == connp);
2175 	ASSERT(connp->conn_udp == udp);
2176 	mutex_destroy(&connp->conn_lock);
2177 	cv_destroy(&connp->conn_cv);
2178 }
2179 
2180 /* ARGSUSED */
2181 static int
2182 rawip_conn_constructor(void *buf, void *cdrarg, int kmflags)
2183 {
2184 	itc_t	*itc = (itc_t *)buf;
2185 	conn_t 	*connp = &itc->itc_conn;
2186 	icmp_t	*icmp = (icmp_t *)&itc[1];
2187 
2188 	bzero(connp, sizeof (conn_t));
2189 	bzero(icmp, sizeof (icmp_t));
2190 
2191 	mutex_init(&connp->conn_lock, NULL, MUTEX_DEFAULT, NULL);
2192 	cv_init(&connp->conn_cv, NULL, CV_DEFAULT, NULL);
2193 	connp->conn_icmp = icmp;
2194 	connp->conn_flags = IPCL_RAWIPCONN;
2195 	connp->conn_ulp = IPPROTO_ICMP;
2196 	icmp->icmp_connp = connp;
2197 	return (0);
2198 }
2199 
2200 /* ARGSUSED */
2201 static void
2202 rawip_conn_destructor(void *buf, void *cdrarg)
2203 {
2204 	itc_t	*itc = (itc_t *)buf;
2205 	conn_t 	*connp = &itc->itc_conn;
2206 	icmp_t	*icmp = (icmp_t *)&itc[1];
2207 
2208 	ASSERT(connp->conn_flags & IPCL_RAWIPCONN);
2209 	ASSERT(icmp->icmp_connp == connp);
2210 	ASSERT(connp->conn_icmp == icmp);
2211 	mutex_destroy(&connp->conn_lock);
2212 	cv_destroy(&connp->conn_cv);
2213 }
2214 
2215 /* ARGSUSED */
2216 static int
2217 rts_conn_constructor(void *buf, void *cdrarg, int kmflags)
2218 {
2219 	itc_t	*itc = (itc_t *)buf;
2220 	conn_t 	*connp = &itc->itc_conn;
2221 	rts_t	*rts = (rts_t *)&itc[1];
2222 
2223 	bzero(connp, sizeof (conn_t));
2224 	bzero(rts, sizeof (rts_t));
2225 
2226 	mutex_init(&connp->conn_lock, NULL, MUTEX_DEFAULT, NULL);
2227 	cv_init(&connp->conn_cv, NULL, CV_DEFAULT, NULL);
2228 	connp->conn_rts = rts;
2229 	connp->conn_flags = IPCL_RTSCONN;
2230 	rts->rts_connp = connp;
2231 	return (0);
2232 }
2233 
2234 /* ARGSUSED */
2235 static void
2236 rts_conn_destructor(void *buf, void *cdrarg)
2237 {
2238 	itc_t	*itc = (itc_t *)buf;
2239 	conn_t 	*connp = &itc->itc_conn;
2240 	rts_t	*rts = (rts_t *)&itc[1];
2241 
2242 	ASSERT(connp->conn_flags & IPCL_RTSCONN);
2243 	ASSERT(rts->rts_connp == connp);
2244 	ASSERT(connp->conn_rts == rts);
2245 	mutex_destroy(&connp->conn_lock);
2246 	cv_destroy(&connp->conn_cv);
2247 }
2248 
2249 /* ARGSUSED */
2250 int
2251 ip_helper_stream_constructor(void *buf, void *cdrarg, int kmflags)
2252 {
2253 	int error;
2254 	netstack_t	*ns;
2255 	int		ret;
2256 	tcp_stack_t	*tcps;
2257 	ip_helper_stream_info_t	*ip_helper_str;
2258 	ip_stack_t	*ipst;
2259 
2260 	ns = netstack_find_by_cred(kcred);
2261 	ASSERT(ns != NULL);
2262 	tcps = ns->netstack_tcp;
2263 	ipst = ns->netstack_ip;
2264 	ASSERT(tcps != NULL);
2265 	ip_helper_str = (ip_helper_stream_info_t *)buf;
2266 
2267 	do {
2268 		error = ldi_open_by_name(DEV_IP, IP_HELPER_STR, kcred,
2269 		    &ip_helper_str->iphs_handle, ipst->ips_ldi_ident);
2270 	} while (error == EINTR);
2271 
2272 	if (error == 0) {
2273 		do {
2274 			error = ldi_ioctl(
2275 			    ip_helper_str->iphs_handle, SIOCSQPTR,
2276 			    (intptr_t)buf, FKIOCTL, kcred, &ret);
2277 		} while (error == EINTR);
2278 
2279 		if (error != 0) {
2280 			(void) ldi_close(
2281 			    ip_helper_str->iphs_handle, 0, kcred);
2282 		}
2283 	}
2284 
2285 	netstack_rele(ipst->ips_netstack);
2286 
2287 	return (error);
2288 }
2289 
2290 /* ARGSUSED */
2291 static void
2292 ip_helper_stream_destructor(void *buf, void *cdrarg)
2293 {
2294 	ip_helper_stream_info_t *ip_helper_str = (ip_helper_stream_info_t *)buf;
2295 
2296 	ip_helper_str->iphs_rq->q_ptr =
2297 	    ip_helper_str->iphs_wq->q_ptr =
2298 	    ip_helper_str->iphs_minfo;
2299 	(void) ldi_close(ip_helper_str->iphs_handle, 0, kcred);
2300 }
2301 
2302 
2303 /*
2304  * Called as part of ipcl_conn_destroy to assert and clear any pointers
2305  * in the conn_t.
2306  */
2307 void
2308 ipcl_conn_cleanup(conn_t *connp)
2309 {
2310 	ASSERT(connp->conn_ire_cache == NULL);
2311 	ASSERT(connp->conn_latch == NULL);
2312 #ifdef notdef
2313 	ASSERT(connp->conn_rq == NULL);
2314 	ASSERT(connp->conn_wq == NULL);
2315 #endif
2316 	ASSERT(connp->conn_cred == NULL);
2317 	ASSERT(connp->conn_g_fanout == NULL);
2318 	ASSERT(connp->conn_g_next == NULL);
2319 	ASSERT(connp->conn_g_prev == NULL);
2320 	ASSERT(connp->conn_policy == NULL);
2321 	ASSERT(connp->conn_fanout == NULL);
2322 	ASSERT(connp->conn_next == NULL);
2323 	ASSERT(connp->conn_prev == NULL);
2324 #ifdef notdef
2325 	/*
2326 	 * The ill and ipif pointers are not cleared before the conn_t
2327 	 * goes away since they do not hold a reference on the ill/ipif.
2328 	 * We should replace these pointers with ifindex/ipaddr_t to
2329 	 * make the code less complex.
2330 	 */
2331 	ASSERT(connp->conn_outgoing_ill == NULL);
2332 	ASSERT(connp->conn_incoming_ill == NULL);
2333 	ASSERT(connp->conn_multicast_ipif == NULL);
2334 	ASSERT(connp->conn_multicast_ill == NULL);
2335 #endif
2336 	ASSERT(connp->conn_oper_pending_ill == NULL);
2337 	ASSERT(connp->conn_ilg == NULL);
2338 	ASSERT(connp->conn_drain_next == NULL);
2339 	ASSERT(connp->conn_drain_prev == NULL);
2340 #ifdef notdef
2341 	/* conn_idl is not cleared when removed from idl list */
2342 	ASSERT(connp->conn_idl == NULL);
2343 #endif
2344 	ASSERT(connp->conn_ipsec_opt_mp == NULL);
2345 	ASSERT(connp->conn_peercred == NULL);
2346 	ASSERT(connp->conn_netstack == NULL);
2347 
2348 	ASSERT(connp->conn_helper_info == NULL);
2349 	/* Clear out the conn_t fields that are not preserved */
2350 	bzero(&connp->conn_start_clr,
2351 	    sizeof (conn_t) -
2352 	    ((uchar_t *)&connp->conn_start_clr - (uchar_t *)connp));
2353 }
2354 
2355 /*
2356  * All conns are inserted in a global multi-list for the benefit of
2357  * walkers. The walk is guaranteed to walk all open conns at the time
2358  * of the start of the walk exactly once. This property is needed to
2359  * achieve some cleanups during unplumb of interfaces. This is achieved
2360  * as follows.
2361  *
2362  * ipcl_conn_create and ipcl_conn_destroy are the only functions that
2363  * call the insert and delete functions below at creation and deletion
2364  * time respectively. The conn never moves or changes its position in this
2365  * multi-list during its lifetime. CONN_CONDEMNED ensures that the refcnt
2366  * won't increase due to walkers, once the conn deletion has started. Note
2367  * that we can't remove the conn from the global list and then wait for
2368  * the refcnt to drop to zero, since walkers would then see a truncated
2369  * list. CONN_INCIPIENT ensures that walkers don't start looking at
2370  * conns until ip_open is ready to make them globally visible.
2371  * The global round robin multi-list locks are held only to get the
2372  * next member/insertion/deletion and contention should be negligible
2373  * if the multi-list is much greater than the number of cpus.
2374  */
2375 void
2376 ipcl_globalhash_insert(conn_t *connp)
2377 {
2378 	int	index;
2379 	struct connf_s	*connfp;
2380 	ip_stack_t	*ipst = connp->conn_netstack->netstack_ip;
2381 
2382 	/*
2383 	 * No need for atomic here. Approximate even distribution
2384 	 * in the global lists is sufficient.
2385 	 */
2386 	ipst->ips_conn_g_index++;
2387 	index = ipst->ips_conn_g_index & (CONN_G_HASH_SIZE - 1);
2388 
2389 	connp->conn_g_prev = NULL;
2390 	/*
2391 	 * Mark as INCIPIENT, so that walkers will ignore this
2392 	 * for now, till ip_open is ready to make it visible globally.
2393 	 */
2394 	connp->conn_state_flags |= CONN_INCIPIENT;
2395 
2396 	connfp = &ipst->ips_ipcl_globalhash_fanout[index];
2397 	/* Insert at the head of the list */
2398 	mutex_enter(&connfp->connf_lock);
2399 	connp->conn_g_next = connfp->connf_head;
2400 	if (connp->conn_g_next != NULL)
2401 		connp->conn_g_next->conn_g_prev = connp;
2402 	connfp->connf_head = connp;
2403 
2404 	/* The fanout bucket this conn points to */
2405 	connp->conn_g_fanout = connfp;
2406 
2407 	mutex_exit(&connfp->connf_lock);
2408 }
2409 
2410 void
2411 ipcl_globalhash_remove(conn_t *connp)
2412 {
2413 	struct connf_s	*connfp;
2414 
2415 	/*
2416 	 * We were never inserted in the global multi list.
2417 	 * IPCL_NONE variety is never inserted in the global multilist
2418 	 * since it is presumed to not need any cleanup and is transient.
2419 	 */
2420 	if (connp->conn_g_fanout == NULL)
2421 		return;
2422 
2423 	connfp = connp->conn_g_fanout;
2424 	mutex_enter(&connfp->connf_lock);
2425 	if (connp->conn_g_prev != NULL)
2426 		connp->conn_g_prev->conn_g_next = connp->conn_g_next;
2427 	else
2428 		connfp->connf_head = connp->conn_g_next;
2429 	if (connp->conn_g_next != NULL)
2430 		connp->conn_g_next->conn_g_prev = connp->conn_g_prev;
2431 	mutex_exit(&connfp->connf_lock);
2432 
2433 	/* Better to stumble on a null pointer than to corrupt memory */
2434 	connp->conn_g_next = NULL;
2435 	connp->conn_g_prev = NULL;
2436 	connp->conn_g_fanout = NULL;
2437 }
2438 
2439 /*
2440  * Walk the list of all conn_t's in the system, calling the function provided
2441  * with the specified argument for each.
2442  * Applies to both IPv4 and IPv6.
2443  *
2444  * IPCs may hold pointers to ipif/ill. To guard against stale pointers
2445  * ipcl_walk() is called to cleanup the conn_t's, typically when an interface is
2446  * unplumbed or removed. New conn_t's that are created while we are walking
2447  * may be missed by this walk, because they are not necessarily inserted
2448  * at the tail of the list. They are new conn_t's and thus don't have any
2449  * stale pointers. The CONN_CLOSING flag ensures that no new reference
2450  * is created to the struct that is going away.
2451  */
2452 void
2453 ipcl_walk(pfv_t func, void *arg, ip_stack_t *ipst)
2454 {
2455 	int	i;
2456 	conn_t	*connp;
2457 	conn_t	*prev_connp;
2458 
2459 	for (i = 0; i < CONN_G_HASH_SIZE; i++) {
2460 		mutex_enter(&ipst->ips_ipcl_globalhash_fanout[i].connf_lock);
2461 		prev_connp = NULL;
2462 		connp = ipst->ips_ipcl_globalhash_fanout[i].connf_head;
2463 		while (connp != NULL) {
2464 			mutex_enter(&connp->conn_lock);
2465 			if (connp->conn_state_flags &
2466 			    (CONN_CONDEMNED | CONN_INCIPIENT)) {
2467 				mutex_exit(&connp->conn_lock);
2468 				connp = connp->conn_g_next;
2469 				continue;
2470 			}
2471 			CONN_INC_REF_LOCKED(connp);
2472 			mutex_exit(&connp->conn_lock);
2473 			mutex_exit(
2474 			    &ipst->ips_ipcl_globalhash_fanout[i].connf_lock);
2475 			(*func)(connp, arg);
2476 			if (prev_connp != NULL)
2477 				CONN_DEC_REF(prev_connp);
2478 			mutex_enter(
2479 			    &ipst->ips_ipcl_globalhash_fanout[i].connf_lock);
2480 			prev_connp = connp;
2481 			connp = connp->conn_g_next;
2482 		}
2483 		mutex_exit(&ipst->ips_ipcl_globalhash_fanout[i].connf_lock);
2484 		if (prev_connp != NULL)
2485 			CONN_DEC_REF(prev_connp);
2486 	}
2487 }
2488 
2489 /*
2490  * Search for a peer TCP/IPv4 loopback conn by doing a reverse lookup on
2491  * the {src, dst, lport, fport} quadruplet.  Returns with conn reference
2492  * held; caller must call CONN_DEC_REF.  Only checks for connected entries
2493  * (peer tcp in ESTABLISHED state).
2494  */
2495 conn_t *
2496 ipcl_conn_tcp_lookup_reversed_ipv4(conn_t *connp, ipha_t *ipha, tcph_t *tcph,
2497     ip_stack_t *ipst)
2498 {
2499 	uint32_t ports;
2500 	uint16_t *pports = (uint16_t *)&ports;
2501 	connf_t	*connfp;
2502 	conn_t	*tconnp;
2503 	boolean_t zone_chk;
2504 
2505 	/*
2506 	 * If either the source of destination address is loopback, then
2507 	 * both endpoints must be in the same Zone.  Otherwise, both of
2508 	 * the addresses are system-wide unique (tcp is in ESTABLISHED
2509 	 * state) and the endpoints may reside in different Zones.
2510 	 */
2511 	zone_chk = (ipha->ipha_src == htonl(INADDR_LOOPBACK) ||
2512 	    ipha->ipha_dst == htonl(INADDR_LOOPBACK));
2513 
2514 	bcopy(tcph->th_fport, &pports[0], sizeof (uint16_t));
2515 	bcopy(tcph->th_lport, &pports[1], sizeof (uint16_t));
2516 
2517 	connfp = &ipst->ips_ipcl_conn_fanout[IPCL_CONN_HASH(ipha->ipha_dst,
2518 	    ports, ipst)];
2519 
2520 	mutex_enter(&connfp->connf_lock);
2521 	for (tconnp = connfp->connf_head; tconnp != NULL;
2522 	    tconnp = tconnp->conn_next) {
2523 
2524 		if (IPCL_CONN_MATCH(tconnp, IPPROTO_TCP,
2525 		    ipha->ipha_dst, ipha->ipha_src, ports) &&
2526 		    tconnp->conn_tcp->tcp_state == TCPS_ESTABLISHED &&
2527 		    (!zone_chk || tconnp->conn_zoneid == connp->conn_zoneid)) {
2528 
2529 			ASSERT(tconnp != connp);
2530 			CONN_INC_REF(tconnp);
2531 			mutex_exit(&connfp->connf_lock);
2532 			return (tconnp);
2533 		}
2534 	}
2535 	mutex_exit(&connfp->connf_lock);
2536 	return (NULL);
2537 }
2538 
2539 /*
2540  * Search for a peer TCP/IPv6 loopback conn by doing a reverse lookup on
2541  * the {src, dst, lport, fport} quadruplet.  Returns with conn reference
2542  * held; caller must call CONN_DEC_REF.  Only checks for connected entries
2543  * (peer tcp in ESTABLISHED state).
2544  */
2545 conn_t *
2546 ipcl_conn_tcp_lookup_reversed_ipv6(conn_t *connp, ip6_t *ip6h, tcph_t *tcph,
2547     ip_stack_t *ipst)
2548 {
2549 	uint32_t ports;
2550 	uint16_t *pports = (uint16_t *)&ports;
2551 	connf_t	*connfp;
2552 	conn_t	*tconnp;
2553 	boolean_t zone_chk;
2554 
2555 	/*
2556 	 * If either the source of destination address is loopback, then
2557 	 * both endpoints must be in the same Zone.  Otherwise, both of
2558 	 * the addresses are system-wide unique (tcp is in ESTABLISHED
2559 	 * state) and the endpoints may reside in different Zones.  We
2560 	 * don't do Zone check for link local address(es) because the
2561 	 * current Zone implementation treats each link local address as
2562 	 * being unique per system node, i.e. they belong to global Zone.
2563 	 */
2564 	zone_chk = (IN6_IS_ADDR_LOOPBACK(&ip6h->ip6_src) ||
2565 	    IN6_IS_ADDR_LOOPBACK(&ip6h->ip6_dst));
2566 
2567 	bcopy(tcph->th_fport, &pports[0], sizeof (uint16_t));
2568 	bcopy(tcph->th_lport, &pports[1], sizeof (uint16_t));
2569 
2570 	connfp = &ipst->ips_ipcl_conn_fanout[IPCL_CONN_HASH_V6(ip6h->ip6_dst,
2571 	    ports, ipst)];
2572 
2573 	mutex_enter(&connfp->connf_lock);
2574 	for (tconnp = connfp->connf_head; tconnp != NULL;
2575 	    tconnp = tconnp->conn_next) {
2576 
2577 		/* We skip tcp_bound_if check here as this is loopback tcp */
2578 		if (IPCL_CONN_MATCH_V6(tconnp, IPPROTO_TCP,
2579 		    ip6h->ip6_dst, ip6h->ip6_src, ports) &&
2580 		    tconnp->conn_tcp->tcp_state == TCPS_ESTABLISHED &&
2581 		    (!zone_chk || tconnp->conn_zoneid == connp->conn_zoneid)) {
2582 
2583 			ASSERT(tconnp != connp);
2584 			CONN_INC_REF(tconnp);
2585 			mutex_exit(&connfp->connf_lock);
2586 			return (tconnp);
2587 		}
2588 	}
2589 	mutex_exit(&connfp->connf_lock);
2590 	return (NULL);
2591 }
2592 
2593 /*
2594  * Find an exact {src, dst, lport, fport} match for a bounced datagram.
2595  * Returns with conn reference held. Caller must call CONN_DEC_REF.
2596  * Only checks for connected entries i.e. no INADDR_ANY checks.
2597  */
2598 conn_t *
2599 ipcl_tcp_lookup_reversed_ipv4(ipha_t *ipha, tcph_t *tcph, int min_state,
2600     ip_stack_t *ipst)
2601 {
2602 	uint32_t ports;
2603 	uint16_t *pports;
2604 	connf_t	*connfp;
2605 	conn_t	*tconnp;
2606 
2607 	pports = (uint16_t *)&ports;
2608 	bcopy(tcph->th_fport, &pports[0], sizeof (uint16_t));
2609 	bcopy(tcph->th_lport, &pports[1], sizeof (uint16_t));
2610 
2611 	connfp = &ipst->ips_ipcl_conn_fanout[IPCL_CONN_HASH(ipha->ipha_dst,
2612 	    ports, ipst)];
2613 
2614 	mutex_enter(&connfp->connf_lock);
2615 	for (tconnp = connfp->connf_head; tconnp != NULL;
2616 	    tconnp = tconnp->conn_next) {
2617 
2618 		if (IPCL_CONN_MATCH(tconnp, IPPROTO_TCP,
2619 		    ipha->ipha_dst, ipha->ipha_src, ports) &&
2620 		    tconnp->conn_tcp->tcp_state >= min_state) {
2621 
2622 			CONN_INC_REF(tconnp);
2623 			mutex_exit(&connfp->connf_lock);
2624 			return (tconnp);
2625 		}
2626 	}
2627 	mutex_exit(&connfp->connf_lock);
2628 	return (NULL);
2629 }
2630 
2631 /*
2632  * Find an exact {src, dst, lport, fport} match for a bounced datagram.
2633  * Returns with conn reference held. Caller must call CONN_DEC_REF.
2634  * Only checks for connected entries i.e. no INADDR_ANY checks.
2635  * Match on ifindex in addition to addresses.
2636  */
2637 conn_t *
2638 ipcl_tcp_lookup_reversed_ipv6(ip6_t *ip6h, tcpha_t *tcpha, int min_state,
2639     uint_t ifindex, ip_stack_t *ipst)
2640 {
2641 	tcp_t	*tcp;
2642 	uint32_t ports;
2643 	uint16_t *pports;
2644 	connf_t	*connfp;
2645 	conn_t	*tconnp;
2646 
2647 	pports = (uint16_t *)&ports;
2648 	pports[0] = tcpha->tha_fport;
2649 	pports[1] = tcpha->tha_lport;
2650 
2651 	connfp = &ipst->ips_ipcl_conn_fanout[IPCL_CONN_HASH_V6(ip6h->ip6_dst,
2652 	    ports, ipst)];
2653 
2654 	mutex_enter(&connfp->connf_lock);
2655 	for (tconnp = connfp->connf_head; tconnp != NULL;
2656 	    tconnp = tconnp->conn_next) {
2657 
2658 		tcp = tconnp->conn_tcp;
2659 		if (IPCL_CONN_MATCH_V6(tconnp, IPPROTO_TCP,
2660 		    ip6h->ip6_dst, ip6h->ip6_src, ports) &&
2661 		    tcp->tcp_state >= min_state &&
2662 		    (tcp->tcp_bound_if == 0 ||
2663 		    tcp->tcp_bound_if == ifindex)) {
2664 
2665 			CONN_INC_REF(tconnp);
2666 			mutex_exit(&connfp->connf_lock);
2667 			return (tconnp);
2668 		}
2669 	}
2670 	mutex_exit(&connfp->connf_lock);
2671 	return (NULL);
2672 }
2673 
2674 /*
2675  * Finds a TCP/IPv4 listening connection; called by tcp_disconnect to locate
2676  * a listener when changing state.
2677  */
2678 conn_t *
2679 ipcl_lookup_listener_v4(uint16_t lport, ipaddr_t laddr, zoneid_t zoneid,
2680     ip_stack_t *ipst)
2681 {
2682 	connf_t		*bind_connfp;
2683 	conn_t		*connp;
2684 	tcp_t		*tcp;
2685 
2686 	/*
2687 	 * Avoid false matches for packets sent to an IP destination of
2688 	 * all zeros.
2689 	 */
2690 	if (laddr == 0)
2691 		return (NULL);
2692 
2693 	ASSERT(zoneid != ALL_ZONES);
2694 
2695 	bind_connfp = &ipst->ips_ipcl_bind_fanout[IPCL_BIND_HASH(lport, ipst)];
2696 	mutex_enter(&bind_connfp->connf_lock);
2697 	for (connp = bind_connfp->connf_head; connp != NULL;
2698 	    connp = connp->conn_next) {
2699 		tcp = connp->conn_tcp;
2700 		if (IPCL_BIND_MATCH(connp, IPPROTO_TCP, laddr, lport) &&
2701 		    IPCL_ZONE_MATCH(connp, zoneid) &&
2702 		    (tcp->tcp_listener == NULL)) {
2703 			CONN_INC_REF(connp);
2704 			mutex_exit(&bind_connfp->connf_lock);
2705 			return (connp);
2706 		}
2707 	}
2708 	mutex_exit(&bind_connfp->connf_lock);
2709 	return (NULL);
2710 }
2711 
2712 /*
2713  * Finds a TCP/IPv6 listening connection; called by tcp_disconnect to locate
2714  * a listener when changing state.
2715  */
2716 conn_t *
2717 ipcl_lookup_listener_v6(uint16_t lport, in6_addr_t *laddr, uint_t ifindex,
2718     zoneid_t zoneid, ip_stack_t *ipst)
2719 {
2720 	connf_t		*bind_connfp;
2721 	conn_t		*connp = NULL;
2722 	tcp_t		*tcp;
2723 
2724 	/*
2725 	 * Avoid false matches for packets sent to an IP destination of
2726 	 * all zeros.
2727 	 */
2728 	if (IN6_IS_ADDR_UNSPECIFIED(laddr))
2729 		return (NULL);
2730 
2731 	ASSERT(zoneid != ALL_ZONES);
2732 
2733 	bind_connfp = &ipst->ips_ipcl_bind_fanout[IPCL_BIND_HASH(lport, ipst)];
2734 	mutex_enter(&bind_connfp->connf_lock);
2735 	for (connp = bind_connfp->connf_head; connp != NULL;
2736 	    connp = connp->conn_next) {
2737 		tcp = connp->conn_tcp;
2738 		if (IPCL_BIND_MATCH_V6(connp, IPPROTO_TCP, *laddr, lport) &&
2739 		    IPCL_ZONE_MATCH(connp, zoneid) &&
2740 		    (tcp->tcp_bound_if == 0 ||
2741 		    tcp->tcp_bound_if == ifindex) &&
2742 		    tcp->tcp_listener == NULL) {
2743 			CONN_INC_REF(connp);
2744 			mutex_exit(&bind_connfp->connf_lock);
2745 			return (connp);
2746 		}
2747 	}
2748 	mutex_exit(&bind_connfp->connf_lock);
2749 	return (NULL);
2750 }
2751 
2752 /*
2753  * ipcl_get_next_conn
2754  *	get the next entry in the conn global list
2755  *	and put a reference on the next_conn.
2756  *	decrement the reference on the current conn.
2757  *
2758  * This is an iterator based walker function that also provides for
2759  * some selection by the caller. It walks through the conn_hash bucket
2760  * searching for the next valid connp in the list, and selects connections
2761  * that are neither closed nor condemned. It also REFHOLDS the conn
2762  * thus ensuring that the conn exists when the caller uses the conn.
2763  */
2764 conn_t *
2765 ipcl_get_next_conn(connf_t *connfp, conn_t *connp, uint32_t conn_flags)
2766 {
2767 	conn_t	*next_connp;
2768 
2769 	if (connfp == NULL)
2770 		return (NULL);
2771 
2772 	mutex_enter(&connfp->connf_lock);
2773 
2774 	next_connp = (connp == NULL) ?
2775 	    connfp->connf_head : connp->conn_g_next;
2776 
2777 	while (next_connp != NULL) {
2778 		mutex_enter(&next_connp->conn_lock);
2779 		if (!(next_connp->conn_flags & conn_flags) ||
2780 		    (next_connp->conn_state_flags &
2781 		    (CONN_CONDEMNED | CONN_INCIPIENT))) {
2782 			/*
2783 			 * This conn has been condemned or
2784 			 * is closing, or the flags don't match
2785 			 */
2786 			mutex_exit(&next_connp->conn_lock);
2787 			next_connp = next_connp->conn_g_next;
2788 			continue;
2789 		}
2790 		CONN_INC_REF_LOCKED(next_connp);
2791 		mutex_exit(&next_connp->conn_lock);
2792 		break;
2793 	}
2794 
2795 	mutex_exit(&connfp->connf_lock);
2796 
2797 	if (connp != NULL)
2798 		CONN_DEC_REF(connp);
2799 
2800 	return (next_connp);
2801 }
2802 
2803 #ifdef CONN_DEBUG
2804 /*
2805  * Trace of the last NBUF refhold/refrele
2806  */
2807 int
2808 conn_trace_ref(conn_t *connp)
2809 {
2810 	int	last;
2811 	conn_trace_t	*ctb;
2812 
2813 	ASSERT(MUTEX_HELD(&connp->conn_lock));
2814 	last = connp->conn_trace_last;
2815 	last++;
2816 	if (last == CONN_TRACE_MAX)
2817 		last = 0;
2818 
2819 	ctb = &connp->conn_trace_buf[last];
2820 	ctb->ctb_depth = getpcstack(ctb->ctb_stack, CONN_STACK_DEPTH);
2821 	connp->conn_trace_last = last;
2822 	return (1);
2823 }
2824 
2825 int
2826 conn_untrace_ref(conn_t *connp)
2827 {
2828 	int	last;
2829 	conn_trace_t	*ctb;
2830 
2831 	ASSERT(MUTEX_HELD(&connp->conn_lock));
2832 	last = connp->conn_trace_last;
2833 	last++;
2834 	if (last == CONN_TRACE_MAX)
2835 		last = 0;
2836 
2837 	ctb = &connp->conn_trace_buf[last];
2838 	ctb->ctb_depth = getpcstack(ctb->ctb_stack, CONN_STACK_DEPTH);
2839 	connp->conn_trace_last = last;
2840 	return (1);
2841 }
2842 #endif
2843