xref: /titanic_44/usr/src/uts/common/inet/sctp/sctp_cookie.c (revision 164c0dd6f561db19bdaf1d0b7f2a8dec44355b69)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/types.h>
30 #include <sys/systm.h>
31 #include <sys/stream.h>
32 #include <sys/cmn_err.h>
33 #include <sys/md5.h>
34 #include <sys/kmem.h>
35 #include <sys/strsubr.h>
36 #include <sys/random.h>
37 #include <sys/tsol/tnet.h>
38 
39 #include <netinet/in.h>
40 #include <netinet/ip6.h>
41 
42 #include <inet/common.h>
43 #include <inet/ip.h>
44 #include <inet/ip6.h>
45 #include <inet/sctp_ip.h>
46 #include <inet/ipclassifier.h>
47 #include "sctp_impl.h"
48 
49 /*
50  * Helper function for SunCluster (PSARC/2005/602) to get the original source
51  * address from the COOKIE
52  */
53 int cl_sctp_cookie_paddr(sctp_chunk_hdr_t *, in6_addr_t *);
54 
55 /*
56  * From RFC 2104. This should probably go into libmd5 (and while
57  * we're at it, maybe we should make a libdigest so we can later
58  * add SHA1 and others, esp. since some weaknesses have been found
59  * with MD5).
60  *
61  * text		IN			pointer to data stream
62  * text_len	IN			length of data stream
63  * key		IN			pointer to authentication key
64  * key_len	IN			length of authentication key
65  * digest	OUT			caller digest to be filled in
66  */
67 static void
68 hmac_md5(uchar_t *text, size_t text_len, uchar_t *key, size_t key_len,
69     uchar_t *digest)
70 {
71 	MD5_CTX context;
72 	uchar_t k_ipad[65];	/* inner padding - key XORd with ipad */
73 	uchar_t k_opad[65];	/* outer padding - key XORd with opad */
74 	uchar_t tk[16];
75 	int i;
76 
77 	/* if key is longer than 64 bytes reset it to key=MD5(key) */
78 	if (key_len > 64) {
79 		MD5_CTX tctx;
80 
81 		MD5Init(&tctx);
82 		MD5Update(&tctx, key, key_len);
83 		MD5Final(tk, &tctx);
84 
85 		key = tk;
86 		key_len = 16;
87 	}
88 
89 	/*
90 	 * the HMAC_MD5 transform looks like:
91 	 *
92 	 * MD5(K XOR opad, MD5(K XOR ipad, text))
93 	 *
94 	 * where K is an n byte key
95 	 * ipad is the byte 0x36 repeated 64 times
96 	 * opad is the byte 0x5c repeated 64 times
97 	 * and text is the data being protected
98 	 */
99 
100 	/* start out by storing key in pads */
101 	bzero(k_ipad, sizeof (k_ipad));
102 	bzero(k_opad, sizeof (k_opad));
103 	bcopy(key, k_ipad, key_len);
104 	bcopy(key, k_opad, key_len);
105 
106 	/* XOR key with ipad and opad values */
107 	for (i = 0; i < 64; i++) {
108 		k_ipad[i] ^= 0x36;
109 		k_opad[i] ^= 0x5c;
110 	}
111 	/*
112 	 * perform inner MD5
113 	 */
114 	MD5Init(&context);			/* init context for 1st */
115 						/* pass */
116 	MD5Update(&context, k_ipad, 64);	/* start with inner pad */
117 	MD5Update(&context, text, text_len);	/* then text of datagram */
118 	MD5Final(digest, &context);		/* finish up 1st pass */
119 	/*
120 	 * perform outer MD5
121 	 */
122 	MD5Init(&context);			/* init context for 2nd */
123 						/* pass */
124 	MD5Update(&context, k_opad, 64);	/* start with outer pad */
125 	MD5Update(&context, digest, 16);	/* then results of 1st */
126 						/* hash */
127 	MD5Final(digest, &context);		/* finish up 2nd pass */
128 }
129 
130 /*
131  * If inmp is non-NULL, and we need to abort, it will use the IP/SCTP
132  * info in initmp to send the abort. Otherwise, no abort will be sent.
133  * If errmp is non-NULL, a chain of unrecognized parameters will
134  * be created and returned via *errmp.
135  *
136  * Returns 1 if the parameters are OK (or there are no parameters), or
137  * 0 if not.
138  */
139 static int
140 validate_init_params(sctp_t *sctp, sctp_chunk_hdr_t *ch,
141     sctp_init_chunk_t *init, mblk_t *inmp, sctp_parm_hdr_t **want_cookie,
142     mblk_t **errmp, int *supp_af, uint_t *sctp_options)
143 {
144 	sctp_parm_hdr_t		*cph;
145 	sctp_init_chunk_t	*ic;
146 	ssize_t			remaining;
147 	uint16_t		serror = 0;
148 	char			*details = NULL;
149 	size_t			errlen = 0;
150 	boolean_t		got_cookie = B_FALSE;
151 	uint16_t		ptype;
152 
153 	if (sctp_options != NULL)
154 		*sctp_options = 0;
155 
156 	/* First validate stream parameters */
157 	if (init->sic_instr == 0 || init->sic_outstr == 0) {
158 		serror = SCTP_ERR_BAD_MANDPARM;
159 		dprint(1,
160 		    ("validate_init_params: bad sid, is=%d os=%d\n",
161 			htons(init->sic_instr), htons(init->sic_outstr)));
162 		goto abort;
163 	}
164 	if (ntohl(init->sic_inittag) == 0) {
165 		serror = SCTP_ERR_BAD_MANDPARM;
166 		dprint(1, ("validate_init_params: inittag = 0\n"));
167 		goto abort;
168 	}
169 
170 	remaining = ntohs(ch->sch_len) - sizeof (*ch);
171 	ic = (sctp_init_chunk_t *)(ch + 1);
172 	remaining -= sizeof (*ic);
173 	if (remaining < sizeof (*cph)) {
174 		/* Nothing to validate */
175 		if (want_cookie != NULL)
176 			goto cookie_abort;
177 		return (1);
178 	}
179 
180 	cph = (sctp_parm_hdr_t *)(ic + 1);
181 
182 	while (cph != NULL) {
183 		ptype = ntohs(cph->sph_type);
184 		switch (ptype) {
185 		case PARM_HBINFO:
186 		case PARM_UNRECOGNIZED:
187 		case PARM_ECN:
188 			/* just ignore them */
189 			break;
190 		case PARM_FORWARD_TSN:
191 			if (sctp_options != NULL)
192 				*sctp_options |= SCTP_PRSCTP_OPTION;
193 			break;
194 		case PARM_COOKIE:
195 			got_cookie = B_TRUE;
196 			if (want_cookie != NULL) {
197 				*want_cookie = cph;
198 			}
199 			break;
200 		case PARM_ADDR4:
201 			*supp_af |= PARM_SUPP_V4;
202 			break;
203 		case PARM_ADDR6:
204 			*supp_af |= PARM_SUPP_V6;
205 			break;
206 		case PARM_COOKIE_PRESERVE:
207 		case PARM_ADAPT_LAYER_IND:
208 			/* These are OK */
209 			break;
210 		case PARM_ADDR_HOST_NAME:
211 			/* Don't support this; abort the association */
212 			serror = SCTP_ERR_BAD_ADDR;
213 			details = (char *)cph;
214 			errlen = ntohs(cph->sph_len);
215 			dprint(1, ("sctp:validate_init_params: host addr\n"));
216 			goto abort;
217 		case PARM_SUPP_ADDRS: {
218 			/* Make sure we have a supported addr intersection */
219 			uint16_t *p, addrtype;
220 			int plen;
221 
222 			plen = ntohs(cph->sph_len);
223 			p = (uint16_t *)(cph + 1);
224 			while (plen > 0) {
225 				addrtype = ntohs(*p);
226 				switch (addrtype) {
227 				case PARM_ADDR6:
228 					*supp_af |= PARM_SUPP_V6;
229 					break;
230 				case PARM_ADDR4:
231 					*supp_af |= PARM_SUPP_V4;
232 					break;
233 				default:
234 					/*
235 					 * Do nothing, silently ignore hostname
236 					 * address.
237 					 */
238 					break;
239 				}
240 				p++;
241 				plen -= sizeof (*p);
242 			}
243 			break;
244 		}
245 		default:
246 			/* Unrecognized param; check the high order bits */
247 			if ((ptype & 0xc000) == 0xc000) {
248 				/*
249 				 * report unrecognized param, and
250 				 * keep processing
251 				 */
252 				if (errmp != NULL) {
253 					if (want_cookie != NULL) {
254 						*errmp = sctp_make_err(sctp,
255 						    PARM_UNRECOGNIZED,
256 						    (void *)cph,
257 						    ntohs(cph->sph_len));
258 					} else {
259 						sctp_add_unrec_parm(cph, errmp);
260 					}
261 				}
262 				break;
263 			}
264 			if (ptype & 0x4000) {
265 				/*
266 				 * Stop processing and drop; report
267 				 * unrecognized param
268 				 */
269 				serror = SCTP_ERR_UNREC_PARM;
270 				details = (char *)cph;
271 				errlen = ntohs(cph->sph_len);
272 				goto abort;
273 			}
274 			if (ptype & 0x8000) {
275 				/* skip and continue processing */
276 				break;
277 			}
278 
279 			/*
280 			 * 2 high bits are clear; stop processing and
281 			 * drop packet
282 			 */
283 			return (0);
284 		}
285 
286 		cph = sctp_next_parm(cph, &remaining);
287 	}
288 	/*
289 	 * Some sanity checks.  The following should not fail unless the
290 	 * other side is broken.
291 	 *
292 	 * 1. If this is a V4 endpoint but V4 address is not
293 	 * supported, abort.
294 	 * 2. If this is a V6 only endpoint but V6 address is
295 	 * not supported, abort.  This assumes that a V6
296 	 * endpoint can use both V4 and V6 addresses.
297 	 * We only care about supp_af when processing INIT, i.e want_cookie
298 	 * is NULL.
299 	 */
300 	if (want_cookie == NULL &&
301 	    ((sctp->sctp_family == AF_INET && !(*supp_af & PARM_SUPP_V4)) ||
302 	    (sctp->sctp_family == AF_INET6 && !(*supp_af & PARM_SUPP_V6) &&
303 	    sctp->sctp_connp->conn_ipv6_v6only))) {
304 		dprint(1, ("sctp:validate_init_params: supp addr\n"));
305 		serror = SCTP_ERR_BAD_ADDR;
306 		goto abort;
307 	}
308 
309 	if (want_cookie != NULL && !got_cookie) {
310 cookie_abort:
311 		dprint(1, ("validate_init_params: cookie absent\n"));
312 		sctp_send_abort(sctp, sctp_init2vtag(ch), SCTP_ERR_MISSING_PARM,
313 		    details, errlen, inmp, 0, B_FALSE);
314 		return (0);
315 	}
316 
317 	/* OK */
318 	return (1);
319 
320 abort:
321 	if (want_cookie != NULL)
322 		return (0);
323 
324 	sctp_send_abort(sctp, sctp_init2vtag(ch), serror, details,
325 	    errlen, inmp, 0, B_FALSE);
326 	return (0);
327 }
328 
329 /*
330  * Initialize params from the INIT and INIT-ACK when the assoc. is
331  * established.
332  */
333 boolean_t
334 sctp_initialize_params(sctp_t *sctp, sctp_init_chunk_t *init,
335     sctp_init_chunk_t *iack)
336 {
337 	/* Get initial TSN */
338 	sctp->sctp_ftsn = ntohl(init->sic_inittsn);
339 	sctp->sctp_lastacked = sctp->sctp_ftsn - 1;
340 
341 	/* Serial number is initialized to the same value as the TSN */
342 	sctp->sctp_fcsn = sctp->sctp_lastacked;
343 
344 	/*
345 	 * Get verification tags; no byteordering is necessary, since
346 	 * verfication tags are never processed except for byte-by-byte
347 	 * comparisons.
348 	 */
349 	sctp->sctp_fvtag = init->sic_inittag;
350 	sctp->sctp_sctph->sh_verf = init->sic_inittag;
351 	sctp->sctp_sctph6->sh_verf = init->sic_inittag;
352 	sctp->sctp_lvtag = iack->sic_inittag;
353 
354 	/* Get the peer's rwnd */
355 	sctp->sctp_frwnd = ntohl(init->sic_a_rwnd);
356 
357 	/* Allocate the in/out-stream counters */
358 	sctp->sctp_num_ostr = iack->sic_outstr;
359 	sctp->sctp_ostrcntrs = kmem_zalloc(sizeof (uint16_t) *
360 	    sctp->sctp_num_ostr, KM_NOSLEEP);
361 	if (sctp->sctp_ostrcntrs == NULL)
362 		return (B_FALSE);
363 
364 	sctp->sctp_num_istr = iack->sic_instr;
365 	sctp->sctp_instr = kmem_zalloc(sizeof (*sctp->sctp_instr) *
366 	    sctp->sctp_num_istr, KM_NOSLEEP);
367 	if (sctp->sctp_instr == NULL) {
368 		kmem_free(sctp->sctp_ostrcntrs, sizeof (uint16_t) *
369 		    sctp->sctp_num_ostr);
370 		sctp->sctp_ostrcntrs = NULL;
371 		return (B_FALSE);
372 	}
373 	return (B_TRUE);
374 }
375 
376 /*
377  * Copy the peer's original source address into addr. This relies on the
378  * following format (see sctp_send_initack() below):
379  * 	relative timestamp for the cookie (int64_t) +
380  * 	cookie lifetime (uint32_t) +
381  * 	local tie-tag (uint32_t) +  peer tie-tag (uint32_t) +
382  * 	Peer's original src ...
383  */
384 int
385 cl_sctp_cookie_paddr(sctp_chunk_hdr_t *ch, in6_addr_t *addr)
386 {
387 	uchar_t	*off;
388 
389 	ASSERT(addr != NULL);
390 
391 	if (ch->sch_id != CHUNK_COOKIE)
392 		return (EINVAL);
393 
394 	off = (uchar_t *)ch + sizeof (*ch) + sizeof (int64_t) +
395 	    sizeof (uint32_t) + sizeof (uint32_t) + sizeof (uint32_t);
396 
397 	bcopy(off, addr, sizeof (*addr));
398 
399 	return (0);
400 }
401 
402 #define	SCTP_CALC_COOKIE_LEN(initcp) \
403 	sizeof (int64_t) +		/* timestamp */			\
404 	sizeof (uint32_t) +		/* cookie lifetime */		\
405 	sizeof (sctp_init_chunk_t) +	/* INIT ACK */			\
406 	sizeof (in6_addr_t) +		/* peer's original source */ 	\
407 	ntohs((initcp)->sch_len) +	/* peer's INIT */		\
408 	sizeof (uint32_t) +		/* local tie-tag */		\
409 	sizeof (uint32_t) +		/* peer tie-tag */		\
410 	sizeof (sctp_parm_hdr_t) +	/* param header */		\
411 	16				/* MD5 hash */
412 
413 void
414 sctp_send_initack(sctp_t *sctp, sctp_chunk_hdr_t *ch, mblk_t *initmp)
415 {
416 	ipha_t			*initiph;
417 	ip6_t			*initip6h;
418 	ipha_t			*iackiph;
419 	ip6_t			*iackip6h;
420 	sctp_chunk_hdr_t	*iack_ch;
421 	sctp_init_chunk_t	*iack;
422 	sctp_init_chunk_t	*init;
423 	sctp_hdr_t		*iacksh;
424 	sctp_hdr_t		*initsh;
425 	size_t			cookielen;
426 	size_t			iacklen;
427 	size_t			ipsctplen;
428 	size_t			errlen = 0;
429 	sctp_parm_hdr_t		*cookieph;
430 	mblk_t			*iackmp;
431 	uint32_t		itag;
432 	uint32_t		itsn;
433 	int64_t			*now;
434 	int64_t			nowt;
435 	uint32_t		*lifetime;
436 	char			*p;
437 	boolean_t		 isv4;
438 	int			supp_af = 0;
439 	uint_t			sctp_options;
440 	uint32_t		*ttag;
441 	int			pad;
442 	mblk_t			*errmp = NULL;
443 	boolean_t		initcollision = B_FALSE;
444 	boolean_t		linklocal = B_FALSE;
445 	cred_t			*cr;
446 
447 	BUMP_LOCAL(sctp->sctp_ibchunks);
448 	isv4 = (IPH_HDR_VERSION(initmp->b_rptr) == IPV4_VERSION);
449 
450 	/* Extract the INIT chunk */
451 	if (isv4) {
452 		initiph = (ipha_t *)initmp->b_rptr;
453 		initsh = (sctp_hdr_t *)((char *)initiph +
454 		    IPH_HDR_LENGTH(initmp->b_rptr));
455 		ipsctplen = sctp->sctp_ip_hdr_len;
456 		supp_af |= PARM_SUPP_V4;
457 	} else {
458 		initip6h = (ip6_t *)initmp->b_rptr;
459 		initsh = (sctp_hdr_t *)(initip6h + 1);
460 		ipsctplen = sctp->sctp_ip_hdr6_len;
461 		if (IN6_IS_ADDR_LINKLOCAL(&initip6h->ip6_src))
462 			linklocal = B_TRUE;
463 		supp_af |= PARM_SUPP_V6;
464 	}
465 	ASSERT(OK_32PTR(initsh));
466 	init = (sctp_init_chunk_t *)((char *)(initsh + 1) + sizeof (*iack_ch));
467 
468 	/* Make sure we like the peer's parameters */
469 	if (validate_init_params(sctp, ch, init, initmp, NULL, &errmp,
470 		&supp_af, &sctp_options) == 0) {
471 		return;
472 	}
473 	if (errmp != NULL)
474 		errlen = msgdsize(errmp);
475 	if (sctp->sctp_family == AF_INET) {
476 		/*
477 		 * Irregardless of the supported address in the INIT, v4
478 		 * must be supported.
479 		 */
480 		supp_af = PARM_SUPP_V4;
481 	}
482 	if (sctp->sctp_state <= SCTPS_LISTEN) {
483 		/* normal, expected INIT: generate new vtag and itsn */
484 		(void) random_get_pseudo_bytes((uint8_t *)&itag, sizeof (itag));
485 		if (itag == 0)
486 			itag = (uint32_t)gethrtime();
487 		itsn = itag + 1;
488 		itag = htonl(itag);
489 	} else if (sctp->sctp_state == SCTPS_COOKIE_WAIT ||
490 	    sctp->sctp_state == SCTPS_COOKIE_ECHOED) {
491 		/* init collision; copy vtag and itsn from sctp */
492 		itag = sctp->sctp_lvtag;
493 		itsn = sctp->sctp_ltsn;
494 		/*
495 		 * In addition we need to send all the params that was sent
496 		 * in our INIT chunk. Essentially, it is only the supported
497 		 * address params that we need to add.
498 		 */
499 		initcollision = B_TRUE;
500 		/*
501 		 * When we sent the INIT, we should have set linklocal in
502 		 * the sctp which should be good enough.
503 		 */
504 		if (linklocal)
505 			linklocal = B_FALSE;
506 	} else {
507 		/* peer restart; generate new vtag but keep everything else */
508 		(void) random_get_pseudo_bytes((uint8_t *)&itag, sizeof (itag));
509 		if (itag == 0)
510 			itag = (uint32_t)gethrtime();
511 		itag = htonl(itag);
512 		itsn = sctp->sctp_ltsn;
513 	}
514 
515 	/*
516 	 * Allocate a mblk for the INIT ACK, consisting of the link layer
517 	 * header, the IP header, the SCTP common header, and INIT ACK chunk,
518 	 * and finally the COOKIE parameter.
519 	 */
520 	cookielen = SCTP_CALC_COOKIE_LEN(ch);
521 	iacklen = sizeof (*iack_ch) + sizeof (*iack) + cookielen;
522 	if (sctp->sctp_send_adaption)
523 		iacklen += (sizeof (sctp_parm_hdr_t) + sizeof (uint32_t));
524 	if (((sctp_options & SCTP_PRSCTP_OPTION) || initcollision) &&
525 	    sctp->sctp_prsctp_aware && sctp_prsctp_enabled) {
526 		iacklen += sctp_options_param_len(sctp, SCTP_PRSCTP_OPTION);
527 	}
528 	if (initcollision)
529 		iacklen += sctp_supaddr_param_len(sctp);
530 	if (!linklocal)
531 		iacklen += sctp_addr_params_len(sctp, supp_af, B_FALSE);
532 	ipsctplen += sizeof (*iacksh) + iacklen;
533 	iacklen += errlen;
534 	if ((pad = ipsctplen % 4) != 0) {
535 		pad = 4 - pad;
536 		ipsctplen += pad;
537 	}
538 	iackmp = allocb_cred(ipsctplen + sctp_wroff_xtra,
539 	    CONN_CRED(sctp->sctp_connp));
540 	if (iackmp == NULL) {
541 		sctp_send_abort(sctp, sctp_init2vtag(ch),
542 		    SCTP_ERR_NO_RESOURCES, NULL, 0, initmp, 0, B_FALSE);
543 		return;
544 	}
545 
546 	/* Copy in the [imcomplete] IP/SCTP composite header */
547 	p = (char *)(iackmp->b_rptr + sctp_wroff_xtra);
548 	iackmp->b_rptr = (uchar_t *)p;
549 	if (isv4) {
550 		bcopy(sctp->sctp_iphc, p, sctp->sctp_hdr_len);
551 		iackiph = (ipha_t *)p;
552 
553 		/* Copy the peer's IP addr */
554 		iackiph->ipha_dst = initiph->ipha_src;
555 		iackiph->ipha_src = initiph->ipha_dst;
556 		iackiph->ipha_length = htons(ipsctplen + errlen);
557 		iacksh = (sctp_hdr_t *)(p + sctp->sctp_ip_hdr_len);
558 	} else {
559 		bcopy(sctp->sctp_iphc6, p, sctp->sctp_hdr6_len);
560 		iackip6h = (ip6_t *)p;
561 
562 		/* Copy the peer's IP addr */
563 		iackip6h->ip6_dst = initip6h->ip6_src;
564 		iackip6h->ip6_src = initip6h->ip6_dst;
565 		iackip6h->ip6_plen = htons(ipsctplen - sizeof (*iackip6h) +
566 		    errlen);
567 		iacksh = (sctp_hdr_t *)(p + sctp->sctp_ip_hdr6_len);
568 	}
569 	ASSERT(OK_32PTR(iacksh));
570 
571 	/* Fill in the holes in the SCTP common header */
572 	iacksh->sh_sport = initsh->sh_dport;
573 	iacksh->sh_dport = initsh->sh_sport;
574 	iacksh->sh_verf = init->sic_inittag;
575 
576 	/* INIT ACK chunk header */
577 	iack_ch = (sctp_chunk_hdr_t *)(iacksh + 1);
578 	iack_ch->sch_id = CHUNK_INIT_ACK;
579 	iack_ch->sch_flags = 0;
580 	iack_ch->sch_len = htons(iacklen);
581 
582 	/* The INIT ACK itself */
583 	iack = (sctp_init_chunk_t *)(iack_ch + 1);
584 	iack->sic_inittag = itag;	/* already in network byteorder */
585 	iack->sic_inittsn = htonl(itsn);
586 
587 	iack->sic_a_rwnd = htonl(sctp->sctp_rwnd);
588 	/* Advertise what we would want to have as stream #'s */
589 	iack->sic_outstr = htons(MIN(sctp->sctp_num_ostr,
590 	    ntohs(init->sic_instr)));
591 	iack->sic_instr = htons(sctp->sctp_num_istr);
592 
593 	p = (char *)(iack + 1);
594 	p += sctp_adaption_code_param(sctp, (uchar_t *)p);
595 	if (initcollision)
596 		p += sctp_supaddr_param(sctp, (uchar_t *)p);
597 	if (!linklocal)
598 		p += sctp_addr_params(sctp, supp_af, (uchar_t *)p);
599 	if (((sctp_options & SCTP_PRSCTP_OPTION) || initcollision) &&
600 	    sctp->sctp_prsctp_aware && sctp_prsctp_enabled) {
601 		p += sctp_options_param(sctp, p, SCTP_PRSCTP_OPTION);
602 	}
603 	/*
604 	 * Generate and lay in the COOKIE parameter.
605 	 *
606 	 * Any change here that results in a change of location for
607 	 * the peer's orig source address must be propagated to the fn
608 	 * cl_sctp_cookie_paddr() above.
609 	 *
610 	 * The cookie consists of:
611 	 * 1. The relative timestamp for the cookie (lbolt64)
612 	 * 2. The cookie lifetime (uint32_t) in tick
613 	 * 3. The local tie-tag
614 	 * 4. The peer tie-tag
615 	 * 5. Peer's original src, used to confirm the validity of address.
616 	 * 6. Our INIT ACK chunk, less any parameters
617 	 * 7. The INIT chunk (may contain parameters)
618 	 * 8. 128-bit MD5 signature.
619 	 *
620 	 * Since the timestamp values will only be evaluated locally, we
621 	 * don't need to worry about byte-ordering them.
622 	 */
623 	cookieph = (sctp_parm_hdr_t *)p;
624 	cookieph->sph_type = htons(PARM_COOKIE);
625 	cookieph->sph_len = htons(cookielen);
626 
627 	/* timestamp */
628 	now = (int64_t *)(cookieph + 1);
629 	nowt = lbolt64;
630 	bcopy(&nowt, now, sizeof (*now));
631 
632 	/* cookie lifetime -- need configuration */
633 	lifetime = (uint32_t *)(now + 1);
634 	*lifetime = sctp->sctp_cookie_lifetime;
635 
636 	/* Set the tie-tags */
637 	ttag = (uint32_t *)(lifetime + 1);
638 	if (sctp->sctp_state <= SCTPS_COOKIE_WAIT) {
639 		*ttag = 0;
640 		ttag++;
641 		*ttag = 0;
642 		ttag++;
643 	} else {
644 		/* local tie-tag (network byte-order) */
645 		*ttag = sctp->sctp_lvtag;
646 		ttag++;
647 		/* peer tie-tag (network byte-order) */
648 		*ttag = sctp->sctp_fvtag;
649 		ttag++;
650 	}
651 	/*
652 	 * Copy in peer's original source address so that we can confirm
653 	 * the reachability later.
654 	 */
655 	p = (char *)ttag;
656 	if (isv4) {
657 		in6_addr_t peer_addr;
658 
659 		IN6_IPADDR_TO_V4MAPPED(iackiph->ipha_dst, &peer_addr);
660 		bcopy(&peer_addr, p, sizeof (in6_addr_t));
661 	} else {
662 		bcopy(&iackip6h->ip6_dst, p, sizeof (in6_addr_t));
663 	}
664 	p += sizeof (in6_addr_t);
665 	/* Copy in our INIT ACK chunk */
666 	bcopy(iack, p, sizeof (*iack));
667 	iack = (sctp_init_chunk_t *)p;
668 	/* Set the # of streams we'll end up using */
669 	iack->sic_outstr = MIN(sctp->sctp_num_ostr, ntohs(init->sic_instr));
670 	iack->sic_instr = MIN(sctp->sctp_num_istr, ntohs(init->sic_outstr));
671 	p += sizeof (*iack);
672 
673 	/* Copy in the peer's INIT chunk */
674 	bcopy(ch, p, ntohs(ch->sch_len));
675 	p += ntohs(ch->sch_len);
676 
677 	/*
678 	 * Calculate the HMAC ICV into the digest slot in buf.
679 	 * First, generate a new secret if the current secret is
680 	 * older than the new secret lifetime parameter permits,
681 	 * copying the current secret to sctp_old_secret.
682 	 */
683 	if (sctp_new_secret_interval > 0 &&
684 	    (sctp->sctp_last_secret_update +
685 	    MSEC_TO_TICK(sctp_new_secret_interval)) <= nowt) {
686 		bcopy(sctp->sctp_secret, sctp->sctp_old_secret,
687 		    SCTP_SECRET_LEN);
688 		(void) random_get_pseudo_bytes(sctp->sctp_secret,
689 		    SCTP_SECRET_LEN);
690 		sctp->sctp_last_secret_update = nowt;
691 	}
692 
693 	hmac_md5((uchar_t *)now, cookielen - sizeof (*cookieph) - 16,
694 	    (uchar_t *)sctp->sctp_secret, SCTP_SECRET_LEN, (uchar_t *)p);
695 
696 	iackmp->b_wptr = iackmp->b_rptr + ipsctplen;
697 	iackmp->b_cont = errmp;		/*  OK if NULL */
698 
699 	if (is_system_labeled() && (cr = DB_CRED(initmp)) != NULL &&
700 	    crgetlabel(cr) != NULL) {
701 		conn_t *connp = sctp->sctp_connp;
702 		int err, adjust;
703 
704 		if (isv4)
705 			err = tsol_check_label(cr, &iackmp, &adjust,
706 			    connp->conn_mac_exempt);
707 		else
708 			err = tsol_check_label_v6(cr, &iackmp, &adjust,
709 			    connp->conn_mac_exempt);
710 		if (err != 0) {
711 			sctp_send_abort(sctp, sctp_init2vtag(ch),
712 			    SCTP_ERR_AUTH_ERR, NULL, 0, initmp, 0, B_FALSE);
713 			freemsg(iackmp);
714 			return;
715 		}
716 		if (isv4) {
717 			iackiph = (ipha_t *)iackmp->b_rptr;
718 			adjust += ntohs(iackiph->ipha_length);
719 			iackiph->ipha_length = htons(adjust);
720 		}
721 	}
722 
723 	/*
724 	 * Stash the conn ptr info. for IP only as e don't have any
725 	 * cached IRE.
726 	 */
727 	SCTP_STASH_IPINFO(iackmp, (ire_t *)NULL);
728 
729 	/* XXX sctp == sctp_g_q, so using its obchunks is valid */
730 	BUMP_LOCAL(sctp->sctp_opkts);
731 	BUMP_LOCAL(sctp->sctp_obchunks);
732 
733 	/* OK to call IP_PUT() here instead of sctp_add_sendq(). */
734 	CONN_INC_REF(sctp->sctp_connp);
735 	iackmp->b_flag |= MSGHASREF;
736 	IP_PUT(iackmp, sctp->sctp_connp, isv4);
737 }
738 
739 void
740 sctp_send_cookie_ack(sctp_t *sctp)
741 {
742 	sctp_chunk_hdr_t *cach;
743 	mblk_t *camp;
744 
745 	camp = sctp_make_mp(sctp, NULL, sizeof (*cach));
746 	if (camp == NULL) {
747 		/* XXX should abort, but don't have the inmp anymore */
748 		SCTP_KSTAT(sctp_send_cookie_ack_failed);
749 		return;
750 	}
751 
752 	cach = (sctp_chunk_hdr_t *)camp->b_wptr;
753 	camp->b_wptr = (uchar_t *)(cach + 1);
754 	cach->sch_id = CHUNK_COOKIE_ACK;
755 	cach->sch_flags = 0;
756 	cach->sch_len = htons(sizeof (*cach));
757 
758 	sctp_set_iplen(sctp, camp);
759 
760 	BUMP_LOCAL(sctp->sctp_obchunks);
761 
762 	sctp_add_sendq(sctp, camp);
763 }
764 
765 static int
766 sctp_find_al_ind(sctp_parm_hdr_t *sph, ssize_t len, uint32_t *adaption_code)
767 {
768 
769 	if (len < sizeof (*sph))
770 		return (-1);
771 	while (sph != NULL) {
772 		if (sph->sph_type == htons(PARM_ADAPT_LAYER_IND) &&
773 		    ntohs(sph->sph_len) >= (sizeof (*sph) +
774 			sizeof (uint32_t))) {
775 			*adaption_code = *(uint32_t *)(sph + 1);
776 			return (0);
777 		}
778 		sph = sctp_next_parm(sph, &len);
779 	}
780 	return (-1);
781 }
782 
783 void
784 sctp_send_cookie_echo(sctp_t *sctp, sctp_chunk_hdr_t *iackch, mblk_t *iackmp)
785 {
786 	mblk_t			*cemp;
787 	mblk_t			*mp = NULL;
788 	mblk_t			*head;
789 	mblk_t			*meta;
790 	sctp_faddr_t		*fp;
791 	sctp_chunk_hdr_t	*cech;
792 	sctp_init_chunk_t	 *iack;
793 	int32_t			cansend;
794 	int32_t			seglen;
795 	size_t			ceclen;
796 	sctp_parm_hdr_t		*cph;
797 	sctp_data_hdr_t		*sdc;
798 	sctp_tf_t		*tf;
799 	int			pad = 0;
800 	int			hdrlen;
801 	mblk_t			*errmp = NULL;
802 	uint_t			sctp_options;
803 	int			error;
804 	uint16_t		old_num_str;
805 
806 	iack = (sctp_init_chunk_t *)(iackch + 1);
807 
808 	cph = NULL;
809 	if (validate_init_params(sctp, iackch, iack, iackmp, &cph, &errmp,
810 	    &pad, &sctp_options) == 0) { /* result in 'pad' ignored */
811 		BUMP_MIB(&sctp_mib, sctpAborted);
812 		sctp_assoc_event(sctp, SCTP_CANT_STR_ASSOC, 0, NULL);
813 		sctp_clean_death(sctp, ECONNABORTED);
814 		return;
815 	}
816 	ASSERT(cph != NULL);
817 
818 	ASSERT(sctp->sctp_cookie_mp == NULL);
819 
820 	/* Got a cookie to echo back; allocate an mblk */
821 	ceclen = sizeof (*cech) + ntohs(cph->sph_len) - sizeof (*cph);
822 	if ((pad = ceclen & (SCTP_ALIGN - 1)) != 0)
823 		pad = SCTP_ALIGN - pad;
824 
825 	if (IPH_HDR_VERSION(iackmp->b_rptr) == IPV4_VERSION)
826 		hdrlen = sctp->sctp_hdr_len;
827 	else
828 		hdrlen = sctp->sctp_hdr6_len;
829 
830 	cemp = allocb(sctp_wroff_xtra + hdrlen + ceclen + pad, BPRI_MED);
831 	if (cemp == NULL) {
832 		SCTP_FADDR_TIMER_RESTART(sctp, sctp->sctp_current,
833 		    sctp->sctp_current->rto);
834 		if (errmp != NULL)
835 			freeb(errmp);
836 		return;
837 	}
838 	cemp->b_rptr += (sctp_wroff_xtra + hdrlen);
839 
840 	/* Process the INIT ACK */
841 	sctp->sctp_sctph->sh_verf = iack->sic_inittag;
842 	sctp->sctp_sctph6->sh_verf = iack->sic_inittag;
843 	sctp->sctp_fvtag = iack->sic_inittag;
844 	sctp->sctp_ftsn = ntohl(iack->sic_inittsn);
845 	sctp->sctp_lastacked = sctp->sctp_ftsn - 1;
846 	sctp->sctp_fcsn = sctp->sctp_lastacked;
847 	sctp->sctp_frwnd = ntohl(iack->sic_a_rwnd);
848 
849 	/*
850 	 * Populate sctp with addresses given in the INIT ACK or IP header.
851 	 * Need to set the df bit in the current fp as it has been cleared
852 	 * in sctp_connect().
853 	 */
854 	sctp->sctp_current->df = B_TRUE;
855 	/*
856 	 * Since IP uses this info during the fanout process, we need to hold
857 	 * the lock for this hash line while performing this operation.
858 	 */
859 	/* XXX sctp_conn_fanout + SCTP_CONN_HASH(sctp->sctp_ports); */
860 	ASSERT(sctp->sctp_conn_tfp != NULL);
861 	tf = sctp->sctp_conn_tfp;
862 	/* sctp isn't a listener so only need to hold conn fanout lock */
863 	mutex_enter(&tf->tf_lock);
864 	if (sctp_get_addrparams(sctp, NULL, iackmp, iackch, NULL) != 0) {
865 		mutex_exit(&tf->tf_lock);
866 		freeb(cemp);
867 		SCTP_FADDR_TIMER_RESTART(sctp, sctp->sctp_current,
868 		    sctp->sctp_current->rto);
869 		if (errmp != NULL)
870 			freeb(errmp);
871 		return;
872 	}
873 	mutex_exit(&tf->tf_lock);
874 
875 	fp = sctp->sctp_current;
876 
877 	/*
878 	 * There could be a case when we get an INIT-ACK again, if the INIT
879 	 * is re-transmitted, for e.g., which means we would have already
880 	 * allocated this resource earlier (also for sctp_instr). In this
881 	 * case we check and re-allocate, if necessary.
882 	 */
883 	old_num_str = sctp->sctp_num_ostr;
884 	if (ntohs(iack->sic_instr) < sctp->sctp_num_ostr)
885 		sctp->sctp_num_ostr = ntohs(iack->sic_instr);
886 	if (sctp->sctp_ostrcntrs == NULL) {
887 		sctp->sctp_ostrcntrs = kmem_zalloc(sizeof (uint16_t) *
888 		    sctp->sctp_num_ostr, KM_NOSLEEP);
889 	} else {
890 		ASSERT(old_num_str > 0);
891 		if (old_num_str != sctp->sctp_num_ostr) {
892 			kmem_free(sctp->sctp_ostrcntrs, sizeof (uint16_t) *
893 			    old_num_str);
894 			sctp->sctp_ostrcntrs = kmem_zalloc(sizeof (uint16_t) *
895 			    sctp->sctp_num_ostr, KM_NOSLEEP);
896 		}
897 	}
898 	if (sctp->sctp_ostrcntrs == NULL) {
899 		freeb(cemp);
900 		SCTP_FADDR_TIMER_RESTART(sctp, fp, fp->rto);
901 		if (errmp != NULL)
902 			freeb(errmp);
903 		return;
904 	}
905 
906 	/*
907 	 * Allocate the in stream tracking array. Comments for sctp_ostrcntrs
908 	 * hold here too.
909 	 */
910 	old_num_str = sctp->sctp_num_istr;
911 	if (ntohs(iack->sic_outstr) < sctp->sctp_num_istr)
912 		sctp->sctp_num_istr = ntohs(iack->sic_outstr);
913 	if (sctp->sctp_instr == NULL) {
914 		sctp->sctp_instr = kmem_zalloc(sizeof (*sctp->sctp_instr) *
915 		    sctp->sctp_num_istr, KM_NOSLEEP);
916 	} else {
917 		ASSERT(old_num_str > 0);
918 		if (old_num_str != sctp->sctp_num_istr) {
919 			kmem_free(sctp->sctp_instr,
920 			    sizeof (*sctp->sctp_instr) * old_num_str);
921 			sctp->sctp_instr = kmem_zalloc(
922 			    sizeof (*sctp->sctp_instr) * sctp->sctp_num_istr,
923 			    KM_NOSLEEP);
924 		}
925 	}
926 	if (sctp->sctp_instr == NULL) {
927 		kmem_free(sctp->sctp_ostrcntrs,
928 		    sizeof (uint16_t) * sctp->sctp_num_ostr);
929 		freeb(cemp);
930 		SCTP_FADDR_TIMER_RESTART(sctp, fp, fp->rto);
931 		if (errmp != NULL)
932 			freeb(errmp);
933 		return;
934 	}
935 
936 	if (!(sctp_options & SCTP_PRSCTP_OPTION) && sctp->sctp_prsctp_aware)
937 		sctp->sctp_prsctp_aware = B_FALSE;
938 
939 	if (sctp_find_al_ind((sctp_parm_hdr_t *)(iack + 1),
940 		ntohs(iackch->sch_len) - (sizeof (*iackch) + sizeof (*iack)),
941 		&sctp->sctp_rx_adaption_code) == 0) {
942 		sctp->sctp_recv_adaption = 1;
943 	}
944 
945 	cech = (sctp_chunk_hdr_t *)cemp->b_rptr;
946 	ASSERT(OK_32PTR(cech));
947 	cech->sch_id = CHUNK_COOKIE;
948 	cech->sch_flags = 0;
949 	cech->sch_len = htons(ceclen);
950 
951 	/* Copy the cookie (less the parm hdr) to the chunk */
952 	bcopy(cph + 1, cech + 1, ceclen - sizeof (*cph));
953 
954 	cemp->b_wptr = cemp->b_rptr + ceclen;
955 
956 	if (sctp->sctp_unsent > 0) {
957 		sctp_msg_hdr_t	*smh;
958 		mblk_t		*prev = NULL;
959 		uint32_t	unsent = 0;
960 
961 		mp = sctp->sctp_xmit_unsent;
962 		do {
963 			smh = (sctp_msg_hdr_t *)mp->b_rptr;
964 			if (smh->smh_sid >= sctp->sctp_num_ostr) {
965 				unsent += smh->smh_msglen;
966 				if (prev != NULL)
967 					prev->b_next = mp->b_next;
968 				else
969 					sctp->sctp_xmit_unsent = mp->b_next;
970 				mp->b_next = NULL;
971 				sctp_sendfail_event(sctp, mp, SCTP_ERR_BAD_SID,
972 				    B_FALSE);
973 				if (prev != NULL)
974 					mp = prev->b_next;
975 				else
976 					mp = sctp->sctp_xmit_unsent;
977 			} else {
978 				prev = mp;
979 				mp = mp->b_next;
980 			}
981 		} while (mp != NULL);
982 		if (unsent > 0) {
983 			ASSERT(sctp->sctp_unsent >= unsent);
984 			sctp->sctp_unsent -= unsent;
985 			/*
986 			 * Update ULP the amount of queued data, which is
987 			 * sent-unack'ed + unsent.
988 			 * This is not necessary, but doesn't harm, we
989 			 * just use unsent instead of sent-unack'ed +
990 			 * unsent, since there won't be any sent-unack'ed
991 			 * here.
992 			 */
993 			if (!SCTP_IS_DETACHED(sctp)) {
994 				sctp->sctp_ulp_xmitted(sctp->sctp_ulpd,
995 				    sctp->sctp_unsent);
996 			}
997 		}
998 		if (sctp->sctp_xmit_unsent == NULL)
999 			sctp->sctp_xmit_unsent_tail = NULL;
1000 	}
1001 	ceclen += pad;
1002 	cansend = MIN(sctp->sctp_unsent, sctp->sctp_frwnd);
1003 	meta = sctp_get_msg_to_send(sctp, &mp, NULL, &error, ceclen,
1004 	    cansend,  NULL);
1005 	/*
1006 	 * The error cannot be anything else since we could have an non-zero
1007 	 * error only if sctp_get_msg_to_send() tries to send a Forward
1008 	 * TSN which will not happen here.
1009 	 */
1010 	ASSERT(error == 0);
1011 	if (meta == NULL)
1012 		goto sendcookie;
1013 	sctp->sctp_xmit_tail = meta;
1014 	sdc = (sctp_data_hdr_t *)mp->b_rptr;
1015 	seglen = ntohs(sdc->sdh_len);
1016 	if ((ceclen + seglen) > fp->sfa_pmss ||
1017 	    (seglen - sizeof (*sdc)) > cansend) {
1018 		goto sendcookie;
1019 	}
1020 	/* OK, if this fails */
1021 	cemp->b_cont = dupmsg(mp);
1022 sendcookie:
1023 	head = sctp_add_proto_hdr(sctp, fp, cemp, 0, NULL);
1024 	if (head == NULL) {
1025 		freemsg(cemp);
1026 		SCTP_FADDR_TIMER_RESTART(sctp, fp, fp->rto);
1027 		if (errmp != NULL)
1028 			freeb(errmp);
1029 		SCTP_KSTAT(sctp_send_cookie_failed);
1030 		return;
1031 	}
1032 	/*
1033 	 * Even if cookie-echo exceeds MTU for one of the hops, it'll
1034 	 * have a chance of getting there.
1035 	 */
1036 	if (fp->isv4) {
1037 		ipha_t *iph = (ipha_t *)head->b_rptr;
1038 		iph->ipha_fragment_offset_and_flags = 0;
1039 	}
1040 	BUMP_LOCAL(sctp->sctp_obchunks);
1041 
1042 	sctp->sctp_cookie_mp = dupmsg(head);
1043 	/* Don't bundle, we will just resend init if this cookie is lost. */
1044 	if (sctp->sctp_cookie_mp == NULL) {
1045 		if (cemp->b_cont != NULL) {
1046 			freemsg(cemp->b_cont);
1047 			cemp->b_cont = NULL;
1048 		}
1049 	} else if (cemp->b_cont != NULL) {
1050 		ASSERT(mp != NULL && mp == meta->b_cont);
1051 		SCTP_CHUNK_CLEAR_FLAGS(cemp->b_cont);
1052 		cemp->b_wptr += pad;
1053 		seglen -= sizeof (*sdc);
1054 		SCTP_CHUNK_SENT(sctp, mp, sdc, fp, seglen, meta);
1055 	}
1056 	if (errmp != NULL)
1057 		linkb(head, errmp);
1058 	sctp->sctp_state = SCTPS_COOKIE_ECHOED;
1059 	SCTP_FADDR_TIMER_RESTART(sctp, fp, fp->rto);
1060 
1061 	sctp_set_iplen(sctp, head);
1062 	sctp_add_sendq(sctp, head);
1063 }
1064 
1065 int
1066 sctp_process_cookie(sctp_t *sctp, sctp_chunk_hdr_t *ch, mblk_t *cmp,
1067     sctp_init_chunk_t **iackpp, sctp_hdr_t *insctph, int *recv_adaption,
1068     in6_addr_t *peer_addr)
1069 {
1070 	int32_t			clen;
1071 	size_t			initplen;
1072 	uchar_t			*p;
1073 	uchar_t			*given_hash;
1074 	uchar_t			needed_hash[16];
1075 	int64_t			ts;
1076 	int64_t			diff;
1077 	uint32_t		*lt;
1078 	sctp_init_chunk_t	*iack;
1079 	sctp_chunk_hdr_t	*initch;
1080 	sctp_init_chunk_t	*init;
1081 	uint32_t		*lttag;
1082 	uint32_t		*fttag;
1083 	uint32_t		ports;
1084 
1085 	BUMP_LOCAL(sctp->sctp_ibchunks);
1086 	/* Verify the ICV */
1087 	clen = ntohs(ch->sch_len) - sizeof (*ch) - 16;
1088 	if (clen < 0) {
1089 		dprint(1, ("invalid cookie chunk length %d\n",
1090 		    ntohs(ch->sch_len)));
1091 
1092 		return (-1);
1093 	}
1094 	p = (uchar_t *)(ch + 1);
1095 
1096 	hmac_md5(p, clen, (uchar_t *)sctp->sctp_secret, SCTP_SECRET_LEN,
1097 	    needed_hash);
1098 
1099 	/* The given hash follows the cookie data */
1100 	given_hash = p + clen;
1101 
1102 	if (bcmp(given_hash, needed_hash, 16) != 0) {
1103 		/* The secret may have changed; try the old secret */
1104 		hmac_md5(p, clen, (uchar_t *)sctp->sctp_old_secret,
1105 		    SCTP_SECRET_LEN, needed_hash);
1106 		if (bcmp(given_hash, needed_hash, 16) != 0) {
1107 			return (-1);
1108 		}
1109 	}
1110 
1111 	/* Timestamp is int64_t, and we only guarantee 32-bit alignment */
1112 	bcopy(p, &ts, sizeof (ts));
1113 	/* Cookie life time, int32_t */
1114 	lt = (uint32_t *)(p + sizeof (ts));
1115 
1116 	/*
1117 	 * To quote PRC, "this is our baby", so let's continue.
1118 	 * We need to pull out the encapsulated INIT ACK and
1119 	 * INIT chunks. Note that we don't process these until
1120 	 * we have verified the timestamp, but we need them before
1121 	 * processing the timestamp since if the time check fails,
1122 	 * we need to get the verification tag from the INIT in order
1123 	 * to send a stale cookie error.
1124 	 */
1125 	lttag = (uint32_t *)(lt + 1);
1126 	fttag = lttag + 1;
1127 	if (peer_addr != NULL)
1128 		bcopy(fttag + 1, peer_addr, sizeof (in6_addr_t));
1129 	iack = (sctp_init_chunk_t *)((char *)(fttag + 1) + sizeof (in6_addr_t));
1130 	initch = (sctp_chunk_hdr_t *)(iack + 1);
1131 	init = (sctp_init_chunk_t *)(initch + 1);
1132 	initplen = ntohs(initch->sch_len) - (sizeof (*init) + sizeof (*initch));
1133 	*iackpp = iack;
1134 	*recv_adaption = 0;
1135 
1136 	/* Check the timestamp */
1137 	diff = lbolt64 - ts;
1138 	if (diff > *lt && (init->sic_inittag != sctp->sctp_fvtag ||
1139 	    iack->sic_inittag != sctp->sctp_lvtag)) {
1140 
1141 		uint32_t staleness;
1142 
1143 		staleness = TICK_TO_USEC(diff);
1144 		staleness = htonl(staleness);
1145 		sctp_send_abort(sctp, init->sic_inittag, SCTP_ERR_STALE_COOKIE,
1146 		    (char *)&staleness, sizeof (staleness), cmp, 1, B_FALSE);
1147 
1148 		dprint(1, ("stale cookie %d\n", staleness));
1149 
1150 		return (-1);
1151 	}
1152 
1153 	/* Check for attack by adding addresses to a restart */
1154 	bcopy(insctph, &ports, sizeof (ports));
1155 	if (sctp_secure_restart_check(cmp, initch, ports, KM_NOSLEEP) != 1) {
1156 		return (-1);
1157 	}
1158 
1159 	/* Look for adaptation code if there any parms in the INIT chunk */
1160 	if ((initplen >= sizeof (sctp_parm_hdr_t)) &&
1161 	    (sctp_find_al_ind((sctp_parm_hdr_t *)(init + 1), initplen,
1162 	    &sctp->sctp_rx_adaption_code) == 0)) {
1163 		*recv_adaption = 1;
1164 	}
1165 
1166 	/* Examine tie-tags */
1167 
1168 	if (sctp->sctp_state >= SCTPS_COOKIE_WAIT) {
1169 		if (sctp->sctp_state == SCTPS_ESTABLISHED &&
1170 		    init->sic_inittag == sctp->sctp_fvtag &&
1171 		    iack->sic_inittag == sctp->sctp_lvtag &&
1172 		    *fttag == 0 && *lttag == 0) {
1173 
1174 			dprint(1, ("duplicate cookie from %x:%x:%x:%x (%d)\n",
1175 			    SCTP_PRINTADDR(sctp->sctp_current->faddr),
1176 			    (int)(sctp->sctp_fport)));
1177 			return (-1);
1178 		}
1179 
1180 		if (init->sic_inittag != sctp->sctp_fvtag &&
1181 		    iack->sic_inittag != sctp->sctp_lvtag &&
1182 		    *fttag == sctp->sctp_fvtag &&
1183 		    *lttag == sctp->sctp_lvtag) {
1184 			int i;
1185 
1186 			/* Section 5.2.4 case A: restart */
1187 			sctp->sctp_fvtag = init->sic_inittag;
1188 			sctp->sctp_lvtag = iack->sic_inittag;
1189 
1190 			sctp->sctp_sctph->sh_verf = init->sic_inittag;
1191 			sctp->sctp_sctph6->sh_verf = init->sic_inittag;
1192 
1193 			sctp->sctp_ftsn = ntohl(init->sic_inittsn);
1194 			sctp->sctp_lastacked = sctp->sctp_ftsn - 1;
1195 			sctp->sctp_frwnd = ntohl(init->sic_a_rwnd);
1196 			sctp->sctp_fcsn = sctp->sctp_lastacked;
1197 
1198 			if (sctp->sctp_state < SCTPS_ESTABLISHED) {
1199 				sctp->sctp_state = SCTPS_ESTABLISHED;
1200 				sctp->sctp_assoc_start_time = (uint32_t)lbolt;
1201 			}
1202 
1203 			dprint(1, ("sctp peer %x:%x:%x:%x (%d) restarted\n",
1204 			    SCTP_PRINTADDR(sctp->sctp_current->faddr),
1205 			    (int)(sctp->sctp_fport)));
1206 			/* reset parameters */
1207 			sctp_congest_reset(sctp);
1208 
1209 			/* reset stream bookkeeping */
1210 			sctp_instream_cleanup(sctp, B_FALSE);
1211 
1212 			sctp->sctp_istr_nmsgs = 0;
1213 			sctp->sctp_rxqueued = 0;
1214 			for (i = 0; i < sctp->sctp_num_ostr; i++) {
1215 				sctp->sctp_ostrcntrs[i] = 0;
1216 			}
1217 			/* XXX flush xmit_list? */
1218 
1219 			return (0);
1220 		} else if (init->sic_inittag != sctp->sctp_fvtag &&
1221 		    iack->sic_inittag == sctp->sctp_lvtag) {
1222 
1223 			/* Section 5.2.4 case B: INIT collision */
1224 			if (sctp->sctp_state < SCTPS_ESTABLISHED) {
1225 				if (!sctp_initialize_params(sctp, init, iack))
1226 					return (-1);	/* Drop? */
1227 				sctp->sctp_state = SCTPS_ESTABLISHED;
1228 				sctp->sctp_assoc_start_time = (uint32_t)lbolt;
1229 			}
1230 
1231 			dprint(1, ("init collision with %x:%x:%x:%x (%d)\n",
1232 			    SCTP_PRINTADDR(sctp->sctp_current->faddr),
1233 			    (int)(sctp->sctp_fport)));
1234 
1235 			return (0);
1236 		} else if (iack->sic_inittag != sctp->sctp_lvtag &&
1237 		    init->sic_inittag == sctp->sctp_fvtag &&
1238 		    *fttag == 0 && *lttag == 0) {
1239 
1240 			/* Section 5.2.4 case C: late COOKIE */
1241 			dprint(1, ("late cookie from %x:%x:%x:%x (%d)\n",
1242 			    SCTP_PRINTADDR(sctp->sctp_current->faddr),
1243 			    (int)(sctp->sctp_fport)));
1244 			return (-1);
1245 		} else if (init->sic_inittag == sctp->sctp_fvtag &&
1246 		    iack->sic_inittag == sctp->sctp_lvtag) {
1247 
1248 			/*
1249 			 * Section 5.2.4 case D: COOKIE ECHO retransmit
1250 			 * Don't check cookie lifetime
1251 			 */
1252 			dprint(1, ("cookie tags match from %x:%x:%x:%x (%d)\n",
1253 			    SCTP_PRINTADDR(sctp->sctp_current->faddr),
1254 			    (int)(sctp->sctp_fport)));
1255 			if (sctp->sctp_state < SCTPS_ESTABLISHED) {
1256 				if (!sctp_initialize_params(sctp, init, iack))
1257 					return (-1);	/* Drop? */
1258 				sctp->sctp_state = SCTPS_ESTABLISHED;
1259 				sctp->sctp_assoc_start_time = (uint32_t)lbolt;
1260 			}
1261 			return (0);
1262 		} else {
1263 			/* unrecognized case -- silently drop it */
1264 			return (-1);
1265 		}
1266 	}
1267 
1268 	return (0);
1269 }
1270 
1271 /*
1272  * Similar to ip_fanout_sctp, except that the src addr(s) are drawn
1273  * from address parameters in an INIT ACK's address list. This
1274  * function is used when an INIT ACK is received but IP's fanout
1275  * function could not find a sctp via the normal lookup routine.
1276  * This can happen when a host sends an INIT ACK from a different
1277  * address than the INIT was sent to.
1278  *
1279  * Returns the sctp_t if found, or NULL if not found.
1280  */
1281 sctp_t *
1282 sctp_addrlist2sctp(mblk_t *mp, sctp_hdr_t *sctph, sctp_chunk_hdr_t *ich,
1283     uint_t ipif_seqid, zoneid_t zoneid)
1284 {
1285 	int isv4;
1286 	ipha_t *iph;
1287 	ip6_t *ip6h;
1288 	in6_addr_t dst;
1289 	in6_addr_t src;
1290 	sctp_parm_hdr_t *ph;
1291 	ssize_t remaining;
1292 	sctp_init_chunk_t *iack;
1293 	uint32_t ports;
1294 	sctp_t *sctp = NULL;
1295 
1296 	ASSERT(ich->sch_id == CHUNK_INIT_ACK);
1297 
1298 	isv4 = (IPH_HDR_VERSION(mp->b_rptr) == IPV4_VERSION);
1299 	if (isv4) {
1300 		iph = (ipha_t *)mp->b_rptr;
1301 		IN6_IPADDR_TO_V4MAPPED(iph->ipha_dst, &dst);
1302 	} else {
1303 		ip6h = (ip6_t *)mp->b_rptr;
1304 		dst = ip6h->ip6_dst;
1305 	}
1306 
1307 	ports = *(uint32_t *)sctph;
1308 
1309 	dprint(1, ("sctp_addrlist2sctp: ports=%u, dst = %x:%x:%x:%x\n",
1310 	    ports, SCTP_PRINTADDR(dst)));
1311 
1312 	/* pull out any address parameters */
1313 	remaining = ntohs(ich->sch_len) - sizeof (*ich) - sizeof (*iack);
1314 	if (remaining < sizeof (*ph)) {
1315 		return (NULL);
1316 	}
1317 
1318 	iack = (sctp_init_chunk_t *)(ich + 1);
1319 	ph = (sctp_parm_hdr_t *)(iack + 1);
1320 
1321 	while (ph != NULL) {
1322 		/*
1323 		 * params have been put in host byteorder by
1324 		 * sctp_check_input()
1325 		 */
1326 		if (ph->sph_type == PARM_ADDR4) {
1327 			IN6_INADDR_TO_V4MAPPED((struct in_addr *)(ph + 1),
1328 			    &src);
1329 
1330 			sctp = sctp_conn_match(&src, &dst, ports, ipif_seqid,
1331 			    zoneid);
1332 
1333 			dprint(1,
1334 			    ("sctp_addrlist2sctp: src=%x:%x:%x:%x, sctp=%p\n",
1335 			    SCTP_PRINTADDR(src), (void *)sctp));
1336 
1337 
1338 			if (sctp != NULL) {
1339 				return (sctp);
1340 			}
1341 		} else if (ph->sph_type == PARM_ADDR6) {
1342 			src = *(in6_addr_t *)(ph + 1);
1343 			sctp = sctp_conn_match(&src, &dst, ports, ipif_seqid,
1344 			    zoneid);
1345 
1346 			dprint(1,
1347 			    ("sctp_addrlist2sctp: src=%x:%x:%x:%x, sctp=%p\n",
1348 			    SCTP_PRINTADDR(src), (void *)sctp));
1349 
1350 			if (sctp != NULL) {
1351 				return (sctp);
1352 			}
1353 		}
1354 
1355 		ph = sctp_next_parm(ph, &remaining);
1356 	}
1357 
1358 	return (NULL);
1359 }
1360