xref: /illumos-gate/usr/src/uts/common/io/ppp/sppp/sppp.c (revision 7c478bd9)
1 /*
2  * sppp.c - Solaris STREAMS PPP multiplexing pseudo-driver
3  *
4  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
5  * Use is subject to license terms.
6  *
7  * Permission to use, copy, modify, and distribute this software and its
8  * documentation is hereby granted, provided that the above copyright
9  * notice appears in all copies.
10  *
11  * SUN MAKES NO REPRESENTATION OR WARRANTIES ABOUT THE SUITABILITY OF
12  * THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
13  * TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
14  * PARTICULAR PURPOSE, OR NON-INFRINGEMENT.  SUN SHALL NOT BE LIABLE FOR
15  * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
16  * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES
17  *
18  * Copyright (c) 1994 The Australian National University.
19  * All rights reserved.
20  *
21  * Permission to use, copy, modify, and distribute this software and its
22  * documentation is hereby granted, provided that the above copyright
23  * notice appears in all copies.  This software is provided without any
24  * warranty, express or implied. The Australian National University
25  * makes no representations about the suitability of this software for
26  * any purpose.
27  *
28  * IN NO EVENT SHALL THE AUSTRALIAN NATIONAL UNIVERSITY BE LIABLE TO ANY
29  * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
30  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
31  * THE AUSTRALIAN NATIONAL UNIVERSITY HAS BEEN ADVISED OF THE POSSIBILITY
32  * OF SUCH DAMAGE.
33  *
34  * THE AUSTRALIAN NATIONAL UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES,
35  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
36  * AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
37  * ON AN "AS IS" BASIS, AND THE AUSTRALIAN NATIONAL UNIVERSITY HAS NO
38  * OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS,
39  * OR MODIFICATIONS.
40  *
41  * This driver is derived from the original SVR4 STREAMS PPP driver
42  * originally written by Paul Mackerras <paul.mackerras@cs.anu.edu.au>.
43  *
44  * Adi Masputra <adi.masputra@sun.com> rewrote and restructured the code
45  * for improved performance and scalability.
46  */
47 
48 #pragma ident	"%Z%%M%	%I%	%E% SMI"
49 #define	RCSID	"$Id: sppp.c,v 1.0 2000/05/08 01:10:12 masputra Exp $"
50 
51 #include <sys/types.h>
52 #include <sys/debug.h>
53 #include <sys/param.h>
54 #include <sys/stat.h>
55 #include <sys/stream.h>
56 #include <sys/stropts.h>
57 #include <sys/sysmacros.h>
58 #include <sys/errno.h>
59 #include <sys/time.h>
60 #include <sys/cmn_err.h>
61 #include <sys/kmem.h>
62 #include <sys/conf.h>
63 #include <sys/dlpi.h>
64 #include <sys/ddi.h>
65 #include <sys/kstat.h>
66 #include <sys/strsun.h>
67 #include <sys/ethernet.h>
68 #include <sys/policy.h>
69 #include <net/ppp_defs.h>
70 #include <net/pppio.h>
71 #include "sppp.h"
72 #include "s_common.h"
73 
74 /*
75  * This is used to tag official Solaris sources.  Please do not define
76  * "INTERNAL_BUILD" when building this software outside of Sun Microsystems.
77  */
78 #ifdef INTERNAL_BUILD
79 /* MODINFO is limited to 32 characters. */
80 const char sppp_module_description[] = "PPP 4.0 mux v%I%";
81 #else /* INTERNAL_BUILD */
82 const char sppp_module_description[] = "ANU PPP mux $Revision: 1.0$";
83 
84 /* LINTED */
85 static const char buildtime[] = "Built " __DATE__ " at " __TIME__
86 #ifdef DEBUG
87 " DEBUG"
88 #endif
89 "\n";
90 #endif /* INTERNAL_BUILD */
91 
92 static void	sppp_inner_ioctl(queue_t *, mblk_t *);
93 static void	sppp_outer_ioctl(queue_t *, mblk_t *);
94 static queue_t	*sppp_send(queue_t *, mblk_t **, spppstr_t *);
95 static queue_t	*sppp_recv(queue_t *, mblk_t **, spppstr_t *);
96 static void	sppp_recv_nondata(queue_t *, mblk_t *, spppstr_t *);
97 static queue_t	*sppp_outpkt(queue_t *, mblk_t **, int, spppstr_t *);
98 static spppstr_t *sppp_inpkt(queue_t *, mblk_t *, spppstr_t *);
99 static int	sppp_kstat_update(kstat_t *, int);
100 static void 	sppp_release_pkts(sppa_t *, uint16_t);
101 
102 /*
103  * sps_list contains the list of active per-stream instance state structures
104  * ordered on the minor device number (see sppp.h for details). All streams
105  * opened to this driver are threaded together in this list.
106  */
107 static spppstr_t *sps_list = NULL;
108 /*
109  * ppa_list contains the list of active per-attachment instance state
110  * structures ordered on the ppa id number (see sppp.h for details). All of
111  * the ppa structures created once per PPPIO_NEWPPA ioctl are threaded together
112  * in this list. There is exactly one ppa structure for a given PPP interface,
113  * and multiple sps streams (upper streams) may share a ppa by performing
114  * an attachment explicitly (PPPIO_ATTACH) or implicitly (DL_ATTACH_REQ).
115  */
116 static sppa_t *ppa_list = NULL;
117 
118 static const char *kstats_names[] = { SPPP_KSTATS_NAMES };
119 static const char *kstats64_names[] = { SPPP_KSTATS64_NAMES };
120 
121 /*
122  * map proto (which is an IANA defined ppp network protocol) to
123  * a bit position indicated by NP_* in ppa_npflag
124  */
125 static uint32_t
126 sppp_ppp2np(uint16_t proto)
127 {
128 	if (proto > 0x7fff)
129 		return (0);
130 	switch (proto) {
131 	case PPP_IP:
132 		return (NP_IP);
133 	case PPP_IPV6:
134 		return (NP_IPV6);
135 	default:
136 		printf("sppp: unknown protocol 0x%x\n", proto);
137 		return (0);
138 	}
139 }
140 
141 /*
142  * sppp_open()
143  *
144  * MT-Perimeters:
145  *    exclusive inner, exclusive outer.
146  *
147  * Description:
148  *    Common open procedure for module.
149  */
150 /* ARGSUSED */
151 int
152 sppp_open(queue_t *q, dev_t *devp, int oflag, int sflag, cred_t *credp)
153 {
154 	spppstr_t	*sps;
155 	spppstr_t	**nextmn;
156 	minor_t		mn;
157 
158 	ASSERT(q != NULL && devp != NULL);
159 	ASSERT(sflag != MODOPEN);
160 
161 	if (q->q_ptr != NULL) {
162 		return (0);		/* already open */
163 	}
164 	if (sflag != CLONEOPEN) {
165 		return (OPENFAIL);
166 	}
167 	/*
168 	 * The sps list is sorted using the minor number as the key. The
169 	 * following code walks the list to find the lowest valued minor
170 	 * number available to be used.
171 	 */
172 	mn = 0;
173 	for (nextmn = &sps_list; (sps = *nextmn) != NULL;
174 	    nextmn = &sps->sps_nextmn) {
175 		if (sps->sps_mn_id != mn) {
176 			break;
177 		}
178 		++mn;
179 	}
180 	sps = (spppstr_t *)kmem_zalloc(sizeof (spppstr_t), KM_SLEEP);
181 	ASSERT(sps != NULL);		/* KM_SLEEP must never return NULL */
182 	sps->sps_nextmn = *nextmn;	/* insert stream in global list */
183 	*nextmn = sps;
184 	sps->sps_mn_id = mn;		/* save minor id for this stream */
185 	sps->sps_rq = q;		/* save read queue pointer */
186 	sps->sps_sap = -1;		/* no sap bound to stream */
187 	sps->sps_dlstate = DL_UNATTACHED; /* dlpi state is unattached */
188 	sps->sps_npmode = NPMODE_DROP;	/* drop all packets initially */
189 	q->q_ptr = WR(q)->q_ptr = (caddr_t)sps;
190 	/*
191 	 * We explicitly disable the automatic queue scheduling for the
192 	 * write-side to obtain complete control over queuing during transmit.
193 	 * Packets will be queued at the upper write queue and the service
194 	 * routine will not be called until it gets scheduled by having the
195 	 * lower write service routine call the qenable(WR(uq)) for all streams
196 	 * attached to the same ppa instance.
197 	 */
198 	noenable(WR(q));
199 	*devp = makedevice(getmajor(*devp), mn);
200 	qprocson(q);
201 	return (0);
202 }
203 
204 /*
205  * Free storage used by a PPA.  This is not called until the last PPA
206  * user closes his connection or reattaches to a different PPA.
207  */
208 static void
209 sppp_free_ppa(sppa_t *ppa)
210 {
211 	sppa_t **nextppa;
212 
213 	ASSERT(ppa->ppa_refcnt == 1);
214 	if (ppa->ppa_kstats != NULL) {
215 		kstat_delete(ppa->ppa_kstats);
216 		ppa->ppa_kstats = NULL;
217 	}
218 	mutex_destroy(&ppa->ppa_sta_lock);
219 	mutex_destroy(&ppa->ppa_npmutex);
220 	rw_destroy(&ppa->ppa_sib_lock);
221 	nextppa = &ppa_list;
222 	while (*nextppa != NULL) {
223 		if (*nextppa == ppa) {
224 			*nextppa = ppa->ppa_nextppa;
225 			break;
226 		}
227 		nextppa = &(*nextppa)->ppa_nextppa;
228 	}
229 	kmem_free(ppa, sizeof (*ppa));
230 }
231 
232 /*
233  * Create a new PPA.  Caller must be exclusive on outer perimeter.
234  */
235 sppa_t *
236 sppp_create_ppa(uint32_t ppa_id)
237 {
238 	sppa_t *ppa;
239 	sppa_t *curppa;
240 	sppa_t **availppa;
241 	char unit[32];		/* Unit name */
242 	const char **cpp;
243 	kstat_t *ksp;
244 	kstat_named_t *knt;
245 
246 	/*
247 	 * NOTE: unit *must* be named for the driver
248 	 * name plus the ppa number so that netstat
249 	 * can find the statistics.
250 	 */
251 	(void) sprintf(unit, "%s%d", PPP_DRV_NAME, ppa_id);
252 	/*
253 	 * Make sure we can allocate a buffer to
254 	 * contain the ppa to be sent upstream, as
255 	 * well as the actual ppa structure and its
256 	 * associated kstat structure.
257 	 */
258 	ppa = (sppa_t *)kmem_zalloc(sizeof (sppa_t),
259 	    KM_NOSLEEP);
260 	ksp = kstat_create(PPP_DRV_NAME, ppa_id, unit, "net", KSTAT_TYPE_NAMED,
261 	    sizeof (sppp_kstats_t) / sizeof (kstat_named_t), 0);
262 
263 	if (ppa == NULL || ksp == NULL) {
264 		if (ppa != NULL) {
265 			kmem_free(ppa, sizeof (sppa_t));
266 		}
267 		if (ksp != NULL) {
268 			kstat_delete(ksp);
269 		}
270 		return (NULL);
271 	}
272 	ppa->ppa_kstats = ksp;		/* chain kstat structure */
273 	ppa->ppa_ppa_id = ppa_id;	/* record ppa id */
274 	ppa->ppa_mtu = PPP_MAXMTU;	/* 65535-(PPP_HDRLEN+PPP_FCSLEN) */
275 	ppa->ppa_mru = PPP_MAXMRU;	/* 65000 */
276 
277 	mutex_init(&ppa->ppa_sta_lock, NULL, MUTEX_DRIVER, NULL);
278 	mutex_init(&ppa->ppa_npmutex, NULL, MUTEX_DRIVER, NULL);
279 	rw_init(&ppa->ppa_sib_lock, NULL, RW_DRIVER, NULL);
280 
281 	/*
282 	 * Prepare and install kstat counters.  Note that for netstat
283 	 * -i to work, there needs to be "ipackets", "opackets",
284 	 * "ierrors", and "oerrors" kstat named variables.
285 	 */
286 	knt = (kstat_named_t *)ksp->ks_data;
287 	for (cpp = kstats_names; cpp < kstats_names + Dim(kstats_names);
288 	    cpp++) {
289 		kstat_named_init(knt, (char *)*cpp, KSTAT_DATA_UINT32);
290 		knt++;
291 	}
292 	for (cpp = kstats64_names; cpp < kstats64_names + Dim(kstats64_names);
293 	    cpp++) {
294 		kstat_named_init(knt, (char *)*cpp, KSTAT_DATA_UINT64);
295 		knt++;
296 	}
297 	ksp->ks_update = sppp_kstat_update;
298 	ksp->ks_private = (void *)ppa;
299 	kstat_install(ksp);
300 
301 	/* link to the next ppa and insert into global list */
302 	availppa = &ppa_list;
303 	while ((curppa = *availppa) != NULL) {
304 		if (ppa_id < curppa->ppa_ppa_id)
305 			break;
306 		availppa = &curppa->ppa_nextppa;
307 	}
308 	ppa->ppa_nextppa = *availppa;
309 	*availppa = ppa;
310 	return (ppa);
311 }
312 
313 /*
314  * sppp_close()
315  *
316  * MT-Perimeters:
317  *    exclusive inner, exclusive outer.
318  *
319  * Description:
320  *    Common close procedure for module.
321  */
322 int
323 sppp_close(queue_t *q)
324 {
325 	spppstr_t	*sps;
326 	spppstr_t	**nextmn;
327 	spppstr_t	*sib;
328 	sppa_t		*ppa;
329 	mblk_t		*mp;
330 
331 	ASSERT(q != NULL && q->q_ptr != NULL);
332 	sps = (spppstr_t *)q->q_ptr;
333 	qprocsoff(q);
334 
335 	ppa = sps->sps_ppa;
336 	if (ppa == NULL) {
337 		ASSERT(!IS_SPS_CONTROL(sps));
338 		goto close_unattached;
339 	}
340 	if (IS_SPS_CONTROL(sps)) {
341 		uint32_t	cnt = 0;
342 
343 		ASSERT(ppa != NULL);
344 		ASSERT(ppa->ppa_ctl == sps);
345 		ppa->ppa_ctl = NULL;
346 		/*
347 		 * STREAMS framework always issues I_UNLINK prior to close,
348 		 * since we only allow I_LINK under the control stream.
349 		 * A given ppa structure has at most one lower stream pointed
350 		 * by the ppa_lower_wq field, because we only allow a single
351 		 * linkage (I_LINK) to be done on the control stream.
352 		 */
353 		ASSERT(ppa->ppa_lower_wq == NULL);
354 		/*
355 		 * Walk through all of sibling streams attached to this ppa,
356 		 * and remove all references to this ppa. We have exclusive
357 		 * access for the entire driver here, so there's no need
358 		 * to hold ppa_sib_lock.
359 		 */
360 		cnt++;
361 		sib = ppa->ppa_streams;
362 		while (sib != NULL) {
363 			ASSERT(ppa == sib->sps_ppa);
364 			sib->sps_npmode = NPMODE_DROP;
365 			sib->sps_flags &= ~(SPS_PIOATTACH | SPS_CACHED);
366 			/*
367 			 * There should be a preallocated hangup
368 			 * message here.  Fetch it and send it up to
369 			 * the stream head.  This will cause IP to
370 			 * mark the interface as "down."
371 			 */
372 			if ((mp = sib->sps_hangup) != NULL) {
373 				sib->sps_hangup = NULL;
374 				/*
375 				 * M_HANGUP works with IP, but snoop
376 				 * is lame and requires M_ERROR.  Send
377 				 * up a clean error code instead.
378 				 *
379 				 * XXX if snoop is fixed, fix this, too.
380 				 */
381 				MTYPE(mp) = M_ERROR;
382 				*mp->b_wptr++ = ENXIO;
383 				putnext(sib->sps_rq, mp);
384 			}
385 			qenable(WR(sib->sps_rq));
386 			cnt++;
387 			sib = sib->sps_nextsib;
388 		}
389 		ASSERT(ppa->ppa_refcnt == cnt);
390 	} else {
391 		ASSERT(ppa->ppa_streams != NULL);
392 		ASSERT(ppa->ppa_ctl != sps);
393 		mp = NULL;
394 		if (sps->sps_sap == PPP_IP) {
395 			ppa->ppa_ip_cache = NULL;
396 			mp = create_lsmsg(PPP_LINKSTAT_IPV4_UNBOUND);
397 		} else if (sps->sps_sap == PPP_IPV6) {
398 			ppa->ppa_ip6_cache = NULL;
399 			mp = create_lsmsg(PPP_LINKSTAT_IPV6_UNBOUND);
400 		}
401 		/* Tell the daemon the bad news. */
402 		if (mp != NULL && ppa->ppa_ctl != NULL &&
403 		    (sps->sps_npmode == NPMODE_PASS ||
404 		    sps->sps_npmode == NPMODE_QUEUE)) {
405 			putnext(ppa->ppa_ctl->sps_rq, mp);
406 		} else {
407 			freemsg(mp);
408 		}
409 		/*
410 		 * Walk through all of sibling streams attached to the
411 		 * same ppa, and remove this stream from the sibling
412 		 * streams list. We have exclusive access for the
413 		 * entire driver here, so there's no need to hold
414 		 * ppa_sib_lock.
415 		 */
416 		sib = ppa->ppa_streams;
417 		if (sib == sps) {
418 			ppa->ppa_streams = sps->sps_nextsib;
419 		} else {
420 			while (sib->sps_nextsib != NULL) {
421 				if (sib->sps_nextsib == sps) {
422 					sib->sps_nextsib = sps->sps_nextsib;
423 					break;
424 				}
425 				sib = sib->sps_nextsib;
426 			}
427 		}
428 		sps->sps_nextsib = NULL;
429 		freemsg(sps->sps_hangup);
430 		sps->sps_hangup = NULL;
431 		/*
432 		 * Check if this is a promiscous stream. If the SPS_PROMISC bit
433 		 * is still set, it means that the stream is closed without
434 		 * ever having issued DL_DETACH_REQ or DL_PROMISCOFF_REQ.
435 		 * In this case, we simply decrement the promiscous counter,
436 		 * and it's safe to do it without holding ppa_sib_lock since
437 		 * we're exclusive (inner and outer) at this point.
438 		 */
439 		if (IS_SPS_PROMISC(sps)) {
440 			ASSERT(ppa->ppa_promicnt > 0);
441 			ppa->ppa_promicnt--;
442 		}
443 	}
444 	/* If we're the only one left, then delete now. */
445 	if (ppa->ppa_refcnt <= 1)
446 		sppp_free_ppa(ppa);
447 	else
448 		ppa->ppa_refcnt--;
449 close_unattached:
450 	q->q_ptr = WR(q)->q_ptr = NULL;
451 	for (nextmn = &sps_list; *nextmn != NULL;
452 	    nextmn = &(*nextmn)->sps_nextmn) {
453 		if (*nextmn == sps) {
454 			*nextmn = sps->sps_nextmn;
455 			break;
456 		}
457 	}
458 	kmem_free(sps, sizeof (spppstr_t));
459 	return (0);
460 }
461 
462 static void
463 sppp_ioctl(struct queue *q, mblk_t *mp)
464 {
465 	spppstr_t	*sps;
466 	spppstr_t	*nextsib;
467 	sppa_t		*ppa;
468 	struct iocblk	*iop;
469 	mblk_t		*nmp;
470 	enum NPmode	npmode;
471 	struct ppp_idle	*pip;
472 	struct ppp_stats64 *psp;
473 	struct ppp_comp_stats *pcsp;
474 	hrtime_t	hrtime;
475 	int		sap;
476 	int		count = 0;
477 	int		error = EINVAL;
478 
479 	sps = (spppstr_t *)q->q_ptr;
480 	ppa = sps->sps_ppa;
481 
482 	iop = (struct iocblk *)mp->b_rptr;
483 	switch (iop->ioc_cmd) {
484 	case PPPIO_NPMODE:
485 		if (!IS_SPS_CONTROL(sps)) {
486 			break;		/* return EINVAL */
487 		} else if (iop->ioc_count != 2 * sizeof (uint32_t) ||
488 		    (mp->b_cont == NULL)) {
489 			error = EPROTO;
490 			break;
491 		}
492 		ASSERT(ppa != NULL);
493 		ASSERT(mp->b_cont->b_rptr != NULL);
494 		ASSERT(sps->sps_npmode == NPMODE_PASS);
495 		sap = ((uint32_t *)mp->b_cont->b_rptr)[0];
496 		npmode = (enum NPmode)((uint32_t *)mp->b_cont->b_rptr)[1];
497 		/*
498 		 * Walk the sibling streams which belong to the same
499 		 * ppa, and try to find a stream with matching sap
500 		 * number.
501 		 */
502 		rw_enter(&ppa->ppa_sib_lock, RW_WRITER);
503 		for (nextsib = ppa->ppa_streams; nextsib != NULL;
504 		    nextsib = nextsib->sps_nextsib) {
505 			if (nextsib->sps_sap == sap) {
506 				break;	/* found it */
507 			}
508 		}
509 		if (nextsib == NULL) {
510 			rw_exit(&ppa->ppa_sib_lock);
511 			break;		/* return EINVAL */
512 		} else {
513 			nextsib->sps_npmode = npmode;
514 			if ((nextsib->sps_npmode != NPMODE_QUEUE) &&
515 			    (WR(nextsib->sps_rq)->q_first != NULL)) {
516 				qenable(WR(nextsib->sps_rq));
517 			}
518 		}
519 		rw_exit(&ppa->ppa_sib_lock);
520 		error = 0;	/* return success */
521 		break;
522 	case PPPIO_GIDLE:
523 		if (ppa == NULL) {
524 			ASSERT(!IS_SPS_CONTROL(sps));
525 			error = ENOLINK;
526 			break;
527 		} else if (!IS_PPA_TIMESTAMP(ppa)) {
528 			break;		/* return EINVAL */
529 		}
530 		if ((nmp = allocb(sizeof (struct ppp_idle),
531 		    BPRI_MED)) == NULL) {
532 			mutex_enter(&ppa->ppa_sta_lock);
533 			ppa->ppa_allocbfail++;
534 			mutex_exit(&ppa->ppa_sta_lock);
535 			error = ENOSR;
536 			break;
537 		}
538 		if (mp->b_cont != NULL) {
539 			freemsg(mp->b_cont);
540 		}
541 		mp->b_cont = nmp;
542 		pip = (struct ppp_idle *)nmp->b_wptr;
543 		nmp->b_wptr += sizeof (struct ppp_idle);
544 		/*
545 		 * Get current timestamp and subtract the tx and rx
546 		 * timestamps to get the actual idle time to be
547 		 * returned.
548 		 */
549 		hrtime = gethrtime();
550 		pip->xmit_idle = (hrtime - ppa->ppa_lasttx) / 1000000000ul;
551 		pip->recv_idle = (hrtime - ppa->ppa_lastrx) / 1000000000ul;
552 		count = msgsize(nmp);
553 		error = 0;
554 		break;		/* return success (error is 0) */
555 	case PPPIO_GTYPE:
556 		nmp = allocb(sizeof (uint32_t), BPRI_MED);
557 		if (nmp == NULL) {
558 			error = ENOSR;
559 			break;
560 		}
561 		if (mp->b_cont != NULL) {
562 			freemsg(mp->b_cont);
563 		}
564 		mp->b_cont = nmp;
565 		/*
566 		 * Let the requestor know that we are the PPP
567 		 * multiplexer (PPPTYP_MUX).
568 		 */
569 		*(uint32_t *)nmp->b_wptr = PPPTYP_MUX;
570 		nmp->b_wptr += sizeof (uint32_t);
571 		count = msgsize(nmp);
572 		error = 0;		/* return success */
573 		break;
574 	case PPPIO_GETSTAT64:
575 		if (ppa == NULL) {
576 			break;		/* return EINVAL */
577 		} else if ((ppa->ppa_lower_wq != NULL) &&
578 		    !IS_PPA_LASTMOD(ppa)) {
579 			mutex_enter(&ppa->ppa_sta_lock);
580 			ppa->ppa_ioctlsfwd++;
581 			mutex_exit(&ppa->ppa_sta_lock);
582 			/*
583 			 * Record the ioctl CMD & ID - this will be
584 			 * used to check the ACK or NAK responses
585 			 * coming from below.
586 			 */
587 			sps->sps_ioc_id = iop->ioc_id;
588 			putnext(ppa->ppa_lower_wq, mp);
589 			return;	/* don't ack or nak the request */
590 		}
591 		nmp = allocb(sizeof (*psp), BPRI_MED);
592 		if (nmp == NULL) {
593 			mutex_enter(&ppa->ppa_sta_lock);
594 			ppa->ppa_allocbfail++;
595 			mutex_exit(&ppa->ppa_sta_lock);
596 			error = ENOSR;
597 			break;
598 		}
599 		if (mp->b_cont != NULL) {
600 			freemsg(mp->b_cont);
601 		}
602 		mp->b_cont = nmp;
603 		psp = (struct ppp_stats64 *)nmp->b_wptr;
604 		/*
605 		 * Copy the contents of ppp_stats64 structure for this
606 		 * ppa and return them to the caller.
607 		 */
608 		mutex_enter(&ppa->ppa_sta_lock);
609 		bcopy(&ppa->ppa_stats, psp, sizeof (*psp));
610 		mutex_exit(&ppa->ppa_sta_lock);
611 		nmp->b_wptr += sizeof (*psp);
612 		count = sizeof (*psp);
613 		error = 0;		/* return success */
614 		break;
615 	case PPPIO_GETCSTAT:
616 		if (ppa == NULL) {
617 			break;		/* return EINVAL */
618 		} else if ((ppa->ppa_lower_wq != NULL) &&
619 		    !IS_PPA_LASTMOD(ppa)) {
620 			mutex_enter(&ppa->ppa_sta_lock);
621 			ppa->ppa_ioctlsfwd++;
622 			mutex_exit(&ppa->ppa_sta_lock);
623 			/*
624 			 * Record the ioctl CMD & ID - this will be
625 			 * used to check the ACK or NAK responses
626 			 * coming from below.
627 			 */
628 			sps->sps_ioc_id = iop->ioc_id;
629 			putnext(ppa->ppa_lower_wq, mp);
630 			return;	/* don't ack or nak the request */
631 		}
632 		nmp = allocb(sizeof (struct ppp_comp_stats), BPRI_MED);
633 		if (nmp == NULL) {
634 			mutex_enter(&ppa->ppa_sta_lock);
635 			ppa->ppa_allocbfail++;
636 			mutex_exit(&ppa->ppa_sta_lock);
637 			error = ENOSR;
638 			break;
639 		}
640 		if (mp->b_cont != NULL) {
641 			freemsg(mp->b_cont);
642 		}
643 		mp->b_cont = nmp;
644 		pcsp = (struct ppp_comp_stats *)nmp->b_wptr;
645 		nmp->b_wptr += sizeof (struct ppp_comp_stats);
646 		bzero((caddr_t)pcsp, sizeof (struct ppp_comp_stats));
647 		count = msgsize(nmp);
648 		error = 0;		/* return success */
649 		break;
650 	}
651 
652 	if (error == 0) {
653 		/* Success; tell the user. */
654 		miocack(q, mp, count, 0);
655 	} else {
656 		/* Failure; send error back upstream. */
657 		miocnak(q, mp, 0, error);
658 	}
659 }
660 
661 /*
662  * sppp_uwput()
663  *
664  * MT-Perimeters:
665  *    shared inner, shared outer.
666  *
667  * Description:
668  *    Upper write-side put procedure. Messages from above arrive here.
669  */
670 int
671 sppp_uwput(queue_t *q, mblk_t *mp)
672 {
673 	queue_t		*nextq;
674 	spppstr_t	*sps;
675 	sppa_t		*ppa;
676 	struct iocblk	*iop;
677 	int		error;
678 
679 	ASSERT(q != NULL && q->q_ptr != NULL);
680 	ASSERT(mp != NULL && mp->b_rptr != NULL);
681 	sps = (spppstr_t *)q->q_ptr;
682 	ppa = sps->sps_ppa;
683 
684 	switch (MTYPE(mp)) {
685 	case M_PCPROTO:
686 	case M_PROTO:
687 		if (IS_SPS_CONTROL(sps)) {
688 			ASSERT(ppa != NULL);
689 			/*
690 			 * Intentionally change this to a high priority
691 			 * message so it doesn't get queued up. M_PROTO is
692 			 * specifically used for signalling between pppd and its
693 			 * kernel-level component(s), such as ppptun, so we
694 			 * make sure that it doesn't get queued up behind
695 			 * data messages.
696 			 */
697 			MTYPE(mp) = M_PCPROTO;
698 			if ((ppa->ppa_lower_wq != NULL) &&
699 			    canputnext(ppa->ppa_lower_wq)) {
700 				mutex_enter(&ppa->ppa_sta_lock);
701 				ppa->ppa_mctlsfwd++;
702 				mutex_exit(&ppa->ppa_sta_lock);
703 				putnext(ppa->ppa_lower_wq, mp);
704 			} else {
705 				mutex_enter(&ppa->ppa_sta_lock);
706 				ppa->ppa_mctlsfwderr++;
707 				mutex_exit(&ppa->ppa_sta_lock);
708 				freemsg(mp);
709 			}
710 		} else {
711 			return (sppp_mproto(q, mp, sps));
712 		}
713 		break;
714 	case M_DATA:
715 		if ((nextq = sppp_send(q, &mp, sps)) != NULL)
716 			putnext(nextq, mp);
717 		break;
718 	case M_IOCTL:
719 		error = EINVAL;
720 		iop = (struct iocblk *)mp->b_rptr;
721 		switch (iop->ioc_cmd) {
722 		case DLIOCRAW:
723 		case DL_IOC_HDR_INFO:
724 		case PPPIO_ATTACH:
725 		case PPPIO_DEBUG:
726 		case PPPIO_DETACH:
727 		case PPPIO_LASTMOD:
728 		case PPPIO_MRU:
729 		case PPPIO_MTU:
730 		case PPPIO_USETIMESTAMP:
731 		case PPPIO_BLOCKNP:
732 		case PPPIO_UNBLOCKNP:
733 			qwriter(q, mp, sppp_inner_ioctl, PERIM_INNER);
734 			return (0);
735 		case I_LINK:
736 		case I_UNLINK:
737 		case PPPIO_NEWPPA:
738 			qwriter(q, mp, sppp_outer_ioctl, PERIM_OUTER);
739 			return (0);
740 		case PPPIO_NPMODE:
741 		case PPPIO_GIDLE:
742 		case PPPIO_GTYPE:
743 		case PPPIO_GETSTAT64:
744 		case PPPIO_GETCSTAT:
745 			/*
746 			 * These require additional auto variables to
747 			 * handle, so (for optimization reasons)
748 			 * they're moved off to a separate function.
749 			 */
750 			sppp_ioctl(q, mp);
751 			return (0);
752 		case PPPIO_GETSTAT:
753 			break;			/* 32 bit interface gone */
754 		default:
755 			if (iop->ioc_cr == NULL ||
756 			    secpolicy_net_config(iop->ioc_cr, B_FALSE) != 0) {
757 				error = EPERM;
758 				break;
759 			} else if ((ppa == NULL) ||
760 			    (ppa->ppa_lower_wq == NULL)) {
761 				break;		/* return EINVAL */
762 			}
763 			mutex_enter(&ppa->ppa_sta_lock);
764 			ppa->ppa_ioctlsfwd++;
765 			mutex_exit(&ppa->ppa_sta_lock);
766 			/*
767 			 * Record the ioctl CMD & ID - this will be used to
768 			 * check the ACK or NAK responses coming from below.
769 			 */
770 			sps->sps_ioc_id = iop->ioc_id;
771 			putnext(ppa->ppa_lower_wq, mp);
772 			return (0);	/* don't ack or nak the request */
773 		}
774 		/* Failure; send error back upstream. */
775 		miocnak(q, mp, 0, error);
776 		break;
777 	case M_FLUSH:
778 		if (*mp->b_rptr & FLUSHW) {
779 			flushq(q, FLUSHDATA);
780 		}
781 		if (*mp->b_rptr & FLUSHR) {
782 			*mp->b_rptr &= ~FLUSHW;
783 			qreply(q, mp);
784 		} else {
785 			freemsg(mp);
786 		}
787 		break;
788 	default:
789 		freemsg(mp);
790 		break;
791 	}
792 	return (0);
793 }
794 
795 /*
796  * sppp_uwsrv()
797  *
798  * MT-Perimeters:
799  *    exclusive inner, shared outer.
800  *
801  * Description:
802  *    Upper write-side service procedure. Note that this procedure does
803  *    not get called when a message is placed on our write-side queue, since
804  *    automatic queue scheduling has been turned off by noenable() when
805  *    the queue was opened. We do this on purpose, as we explicitly control
806  *    the write-side queue. Therefore, this procedure gets called when
807  *    the lower write service procedure qenable() the upper write stream queue.
808  */
809 int
810 sppp_uwsrv(queue_t *q)
811 {
812 	spppstr_t	*sps;
813 	mblk_t		*mp;
814 	queue_t		*nextq;
815 
816 	ASSERT(q != NULL && q->q_ptr != NULL);
817 	sps = (spppstr_t *)q->q_ptr;
818 	while ((mp = getq(q)) != NULL) {
819 		if ((nextq = sppp_outpkt(q, &mp, msgdsize(mp), sps)) == NULL) {
820 			if (mp != NULL) {
821 				if (putbq(q, mp) == 0)
822 					freemsg(mp);
823 				break;
824 			}
825 		} else {
826 			putnext(nextq, mp);
827 		}
828 	}
829 	return (0);
830 }
831 
832 void
833 sppp_remove_ppa(spppstr_t *sps)
834 {
835 	spppstr_t *nextsib;
836 	sppa_t *ppa = sps->sps_ppa;
837 
838 	rw_enter(&ppa->ppa_sib_lock, RW_WRITER);
839 	if (ppa->ppa_refcnt <= 1) {
840 		rw_exit(&ppa->ppa_sib_lock);
841 		sppp_free_ppa(ppa);
842 	} else {
843 		nextsib = ppa->ppa_streams;
844 		if (nextsib == sps) {
845 			ppa->ppa_streams = sps->sps_nextsib;
846 		} else {
847 			while (nextsib->sps_nextsib != NULL) {
848 				if (nextsib->sps_nextsib == sps) {
849 					nextsib->sps_nextsib =
850 					    sps->sps_nextsib;
851 					break;
852 				}
853 				nextsib = nextsib->sps_nextsib;
854 			}
855 		}
856 		ppa->ppa_refcnt--;
857 		/*
858 		 * And if this stream was marked as promiscuous
859 		 * (SPS_PROMISC), then we need to update the
860 		 * promiscuous streams count. This should only happen
861 		 * when DL_DETACH_REQ is issued prior to marking the
862 		 * stream as non-promiscuous, through
863 		 * DL_PROMISCOFF_REQ request.
864 		 */
865 		if (IS_SPS_PROMISC(sps)) {
866 			ASSERT(ppa->ppa_promicnt > 0);
867 			ppa->ppa_promicnt--;
868 		}
869 		rw_exit(&ppa->ppa_sib_lock);
870 	}
871 	sps->sps_nextsib = NULL;
872 	sps->sps_ppa = NULL;
873 	freemsg(sps->sps_hangup);
874 	sps->sps_hangup = NULL;
875 }
876 
877 sppa_t *
878 sppp_find_ppa(uint32_t ppa_id)
879 {
880 	sppa_t *ppa;
881 
882 	for (ppa = ppa_list; ppa != NULL; ppa = ppa->ppa_nextppa) {
883 		if (ppa->ppa_ppa_id == ppa_id) {
884 			break;	/* found the ppa */
885 		}
886 	}
887 	return (ppa);
888 }
889 
890 /*
891  * sppp_inner_ioctl()
892  *
893  * MT-Perimeters:
894  *    exclusive inner, shared outer
895  *
896  * Description:
897  *    Called by sppp_uwput as a result of receiving ioctls which require
898  *    an exclusive access at the inner perimeter.
899  */
900 static void
901 sppp_inner_ioctl(queue_t *q, mblk_t *mp)
902 {
903 	spppstr_t	*sps;
904 	sppa_t		*ppa;
905 	struct iocblk	*iop;
906 	mblk_t		*nmp;
907 	int		error = EINVAL;
908 	int		count = 0;
909 	int		dbgcmd;
910 	int		mru, mtu;
911 	uint32_t	ppa_id;
912 	hrtime_t	hrtime;
913 	uint16_t	proto;
914 
915 	ASSERT(q != NULL && q->q_ptr != NULL);
916 	ASSERT(mp != NULL && mp->b_rptr != NULL);
917 
918 	sps = (spppstr_t *)q->q_ptr;
919 	ppa = sps->sps_ppa;
920 	iop = (struct iocblk *)mp->b_rptr;
921 	switch (iop->ioc_cmd) {
922 	case DLIOCRAW:
923 		if (IS_SPS_CONTROL(sps)) {
924 			break;		/* return EINVAL */
925 		}
926 		sps->sps_flags |= SPS_RAWDATA;
927 		error = 0;		/* return success */
928 		break;
929 	case DL_IOC_HDR_INFO:
930 		if (IS_SPS_CONTROL(sps)) {
931 			break;		/* return EINVAL */
932 		} else if ((mp->b_cont == NULL) ||
933 		    *((t_uscalar_t *)mp->b_cont->b_rptr) != DL_UNITDATA_REQ ||
934 		    (MBLKL(mp->b_cont) < (sizeof (dl_unitdata_req_t) +
935 			SPPP_ADDRL))) {
936 			error = EPROTO;
937 			break;
938 		} else if (ppa == NULL) {
939 			error = ENOLINK;
940 			break;
941 		}
942 		if ((nmp = allocb(PPP_HDRLEN, BPRI_MED)) == NULL) {
943 			mutex_enter(&ppa->ppa_sta_lock);
944 			ppa->ppa_allocbfail++;
945 			mutex_exit(&ppa->ppa_sta_lock);
946 			error = ENOMEM;
947 			break;
948 		}
949 		*(uchar_t *)nmp->b_wptr++ = PPP_ALLSTATIONS;
950 		*(uchar_t *)nmp->b_wptr++ = PPP_UI;
951 		*(uchar_t *)nmp->b_wptr++ = sps->sps_sap >> 8;
952 		*(uchar_t *)nmp->b_wptr++ = sps->sps_sap & 0xff;
953 		ASSERT(MBLKL(nmp) == PPP_HDRLEN);
954 
955 		linkb(mp, nmp);
956 		sps->sps_flags |= SPS_FASTPATH;
957 		error = 0;		/* return success */
958 		count = msgsize(nmp);
959 		break;
960 	case PPPIO_ATTACH:
961 		if (IS_SPS_CONTROL(sps) || IS_SPS_PIOATTACH(sps) ||
962 		    (sps->sps_dlstate != DL_UNATTACHED) ||
963 		    (iop->ioc_count != sizeof (uint32_t))) {
964 			break;		/* return EINVAL */
965 		} else if (mp->b_cont == NULL) {
966 			error = EPROTO;
967 			break;
968 		}
969 		ASSERT(mp->b_cont->b_rptr != NULL);
970 		/* If there's something here, it's detached. */
971 		if (ppa != NULL) {
972 			sppp_remove_ppa(sps);
973 		}
974 		ppa_id = *(uint32_t *)mp->b_cont->b_rptr;
975 		ppa = sppp_find_ppa(ppa_id);
976 		/*
977 		 * If we can't find it, then it's either because the requestor
978 		 * has supplied a wrong ppa_id to be attached to, or because
979 		 * the control stream for the specified ppa_id has been closed
980 		 * before we get here.
981 		 */
982 		if (ppa == NULL) {
983 			error = ENOENT;
984 			break;
985 		}
986 		/*
987 		 * Preallocate the hangup message so that we're always
988 		 * able to send this upstream in the event of a
989 		 * catastrophic failure.
990 		 */
991 		if ((sps->sps_hangup = allocb(1, BPRI_MED)) == NULL) {
992 			error = ENOSR;
993 			break;
994 		}
995 		/*
996 		 * There are two ways to attach a stream to a ppa: one is
997 		 * through DLPI (DL_ATTACH_REQ) and the other is through
998 		 * PPPIO_ATTACH. This is why we need to distinguish whether or
999 		 * not a stream was allocated via PPPIO_ATTACH, so that we can
1000 		 * properly detach it when we receive PPPIO_DETACH ioctl
1001 		 * request.
1002 		 */
1003 		sps->sps_flags |= SPS_PIOATTACH;
1004 		sps->sps_ppa = ppa;
1005 		/*
1006 		 * Add this stream to the head of the list of sibling streams
1007 		 * which belong to the same ppa as specified.
1008 		 */
1009 		rw_enter(&ppa->ppa_sib_lock, RW_WRITER);
1010 		ppa->ppa_refcnt++;
1011 		sps->sps_nextsib = ppa->ppa_streams;
1012 		ppa->ppa_streams = sps;
1013 		rw_exit(&ppa->ppa_sib_lock);
1014 		error = 0;		/* return success */
1015 		break;
1016 	case PPPIO_BLOCKNP:
1017 	case PPPIO_UNBLOCKNP:
1018 		if (iop->ioc_cr == NULL ||
1019 		    secpolicy_net_config(iop->ioc_cr, B_FALSE) != 0) {
1020 			error = EPERM;
1021 			break;
1022 		}
1023 		error = miocpullup(mp, sizeof (uint16_t));
1024 		if (error != 0)
1025 			break;
1026 		ASSERT(mp->b_cont->b_rptr != NULL);
1027 		proto = *(uint16_t *)mp->b_cont->b_rptr;
1028 		if (iop->ioc_cmd == PPPIO_BLOCKNP) {
1029 			uint32_t npflagpos = sppp_ppp2np(proto);
1030 			/*
1031 			 * Mark proto as blocked in ppa_npflag until the
1032 			 * corresponding queues for proto have been plumbed.
1033 			 */
1034 			if (npflagpos != 0) {
1035 				mutex_enter(&ppa->ppa_npmutex);
1036 				ppa->ppa_npflag |= (1 << npflagpos);
1037 				mutex_exit(&ppa->ppa_npmutex);
1038 			} else {
1039 				error = EINVAL;
1040 			}
1041 		} else {
1042 			/*
1043 			 * reset ppa_npflag and release proto
1044 			 * packets that were being held in control queue.
1045 			 */
1046 			sppp_release_pkts(ppa, proto);
1047 		}
1048 		break;
1049 	case PPPIO_DEBUG:
1050 		if (iop->ioc_cr == NULL ||
1051 		    secpolicy_net_config(iop->ioc_cr, B_FALSE) != 0) {
1052 			error = EPERM;
1053 			break;
1054 		} else if (iop->ioc_count != sizeof (uint32_t)) {
1055 			break;		/* return EINVAL */
1056 		} else if (mp->b_cont == NULL) {
1057 			error = EPROTO;
1058 			break;
1059 		}
1060 		ASSERT(mp->b_cont->b_rptr != NULL);
1061 		dbgcmd = *(uint32_t *)mp->b_cont->b_rptr;
1062 		/*
1063 		 * We accept PPPDBG_LOG + PPPDBG_DRIVER value as an indication
1064 		 * that SPS_KDEBUG needs to be enabled for this upper stream.
1065 		 */
1066 		if (dbgcmd == PPPDBG_LOG + PPPDBG_DRIVER) {
1067 			sps->sps_flags |= SPS_KDEBUG;
1068 			error = 0;	/* return success */
1069 			break;
1070 		}
1071 		/*
1072 		 * Otherwise, for any other values, we send them down only if
1073 		 * there is an attachment and if the attachment has something
1074 		 * linked underneath it.
1075 		 */
1076 		if ((ppa == NULL) || (ppa->ppa_lower_wq == NULL)) {
1077 			error = ENOLINK;
1078 			break;
1079 		}
1080 		mutex_enter(&ppa->ppa_sta_lock);
1081 		ppa->ppa_ioctlsfwd++;
1082 		mutex_exit(&ppa->ppa_sta_lock);
1083 		/*
1084 		 * Record the ioctl CMD & ID - this will be used to check the
1085 		 * ACK or NAK responses coming from below.
1086 		 */
1087 		sps->sps_ioc_id = iop->ioc_id;
1088 		putnext(ppa->ppa_lower_wq, mp);
1089 		return;			/* don't ack or nak the request */
1090 	case PPPIO_DETACH:
1091 		if (!IS_SPS_PIOATTACH(sps)) {
1092 			break;		/* return EINVAL */
1093 		}
1094 		/*
1095 		 * The SPS_PIOATTACH flag set on the stream tells us that
1096 		 * the ppa field is still valid. In the event that the control
1097 		 * stream be closed prior to this stream's detachment, the
1098 		 * SPS_PIOATTACH flag would have been cleared from this stream
1099 		 * during close; in that case we won't get here.
1100 		 */
1101 		ASSERT(ppa != NULL);
1102 		ASSERT(ppa->ppa_ctl != sps);
1103 		ASSERT(sps->sps_dlstate == DL_UNATTACHED);
1104 
1105 		/*
1106 		 * We don't actually detach anything until the stream is
1107 		 * closed or reattached.
1108 		 */
1109 
1110 		sps->sps_flags &= ~SPS_PIOATTACH;
1111 		error = 0;		/* return success */
1112 		break;
1113 	case PPPIO_LASTMOD:
1114 		if (!IS_SPS_CONTROL(sps)) {
1115 			break;		/* return EINVAL */
1116 		}
1117 		ASSERT(ppa != NULL);
1118 		ppa->ppa_flags |= PPA_LASTMOD;
1119 		error = 0;		/* return success */
1120 		break;
1121 	case PPPIO_MRU:
1122 		if (!IS_SPS_CONTROL(sps) ||
1123 		    (iop->ioc_count != sizeof (uint32_t))) {
1124 			break;		/* return EINVAL */
1125 		} else if (mp->b_cont == NULL) {
1126 			error = EPROTO;
1127 			break;
1128 		}
1129 		ASSERT(ppa != NULL);
1130 		ASSERT(mp->b_cont->b_rptr != NULL);
1131 		mru = *(uint32_t *)mp->b_cont->b_rptr;
1132 		if ((mru <= 0) || (mru > PPP_MAXMRU)) {
1133 			error = EPROTO;
1134 			break;
1135 		}
1136 		if (mru < PPP_MRU) {
1137 			mru = PPP_MRU;
1138 		}
1139 		ppa->ppa_mru = (uint16_t)mru;
1140 		/*
1141 		 * If there's something beneath this driver for the ppa, then
1142 		 * inform it (or them) of the MRU size. Only do this is we
1143 		 * are not the last PPP module on the stream.
1144 		 */
1145 		if (!IS_PPA_LASTMOD(ppa) && (ppa->ppa_lower_wq != NULL)) {
1146 			(void) putctl4(ppa->ppa_lower_wq, M_CTL, PPPCTL_MRU,
1147 			    mru);
1148 		}
1149 		error = 0;		/* return success */
1150 		break;
1151 	case PPPIO_MTU:
1152 		if (!IS_SPS_CONTROL(sps) ||
1153 		    (iop->ioc_count != sizeof (uint32_t))) {
1154 			break;		/* return EINVAL */
1155 		} else if (mp->b_cont == NULL) {
1156 			error = EPROTO;
1157 			break;
1158 		}
1159 		ASSERT(ppa != NULL);
1160 		ASSERT(mp->b_cont->b_rptr != NULL);
1161 		mtu = *(uint32_t *)mp->b_cont->b_rptr;
1162 		if ((mtu <= 0) || (mtu > PPP_MAXMTU)) {
1163 			error = EPROTO;
1164 			break;
1165 		}
1166 		ppa->ppa_mtu = (uint16_t)mtu;
1167 		/*
1168 		 * If there's something beneath this driver for the ppa, then
1169 		 * inform it (or them) of the MTU size. Only do this if we
1170 		 * are not the last PPP module on the stream.
1171 		 */
1172 		if (!IS_PPA_LASTMOD(ppa) && (ppa->ppa_lower_wq != NULL)) {
1173 			(void) putctl4(ppa->ppa_lower_wq, M_CTL, PPPCTL_MTU,
1174 			    mtu);
1175 		}
1176 		error = 0;		/* return success */
1177 		break;
1178 	case PPPIO_USETIMESTAMP:
1179 		if (!IS_SPS_CONTROL(sps)) {
1180 			break;		/* return EINVAL */
1181 		}
1182 		if (!IS_PPA_TIMESTAMP(ppa)) {
1183 			hrtime = gethrtime();
1184 			ppa->ppa_lasttx = ppa->ppa_lastrx = hrtime;
1185 			ppa->ppa_flags |= PPA_TIMESTAMP;
1186 		}
1187 		error = 0;
1188 		break;
1189 	}
1190 
1191 	if (error == 0) {
1192 		/* Success; tell the user */
1193 		miocack(q, mp, count, 0);
1194 	} else {
1195 		/* Failure; send error back upstream */
1196 		miocnak(q, mp, 0, error);
1197 	}
1198 }
1199 
1200 /*
1201  * sppp_outer_ioctl()
1202  *
1203  * MT-Perimeters:
1204  *    exclusive inner, exclusive outer
1205  *
1206  * Description:
1207  *    Called by sppp_uwput as a result of receiving ioctls which require
1208  *    an exclusive access at the outer perimeter.
1209  */
1210 static void
1211 sppp_outer_ioctl(queue_t *q, mblk_t *mp)
1212 {
1213 	spppstr_t	*sps;
1214 	spppstr_t	*nextsib;
1215 	queue_t		*lwq;
1216 	sppa_t		*ppa;
1217 	struct iocblk	*iop;
1218 	int		error = EINVAL;
1219 	int		count = 0;
1220 	uint32_t	ppa_id;
1221 	mblk_t		*nmp;
1222 
1223 	ASSERT(q != NULL && q->q_ptr != NULL);
1224 	ASSERT(mp != NULL && mp->b_rptr != NULL);
1225 
1226 	sps = (spppstr_t *)q->q_ptr;
1227 	ppa = sps->sps_ppa;
1228 	iop = (struct iocblk *)mp->b_rptr;
1229 	switch (iop->ioc_cmd) {
1230 	case I_LINK:
1231 		if (!IS_SPS_CONTROL(sps)) {
1232 			break;		/* return EINVAL */
1233 		} else if (ppa->ppa_lower_wq != NULL) {
1234 			error = EEXIST;
1235 			break;
1236 		}
1237 		ASSERT(ppa->ppa_ctl != NULL);
1238 		ASSERT(sps->sps_npmode == NPMODE_PASS);
1239 		ASSERT(mp->b_cont != NULL && mp->b_cont->b_rptr != NULL);
1240 
1241 		lwq = ((struct linkblk *)mp->b_cont->b_rptr)->l_qbot;
1242 		ASSERT(lwq != NULL);
1243 
1244 		ppa->ppa_lower_wq = lwq;
1245 		lwq->q_ptr = RD(lwq)->q_ptr = (caddr_t)ppa;
1246 		/*
1247 		 * Unblock upper network streams which now feed this lower
1248 		 * stream. We don't need to hold ppa_sib_lock here, since we
1249 		 * are writer at the outer perimeter.
1250 		 */
1251 		if (WR(sps->sps_rq)->q_first != NULL)
1252 			qenable(WR(sps->sps_rq));
1253 		for (nextsib = ppa->ppa_streams; nextsib != NULL;
1254 		    nextsib = nextsib->sps_nextsib) {
1255 			nextsib->sps_npmode = NPMODE_PASS;
1256 			if (WR(nextsib->sps_rq)->q_first != NULL) {
1257 				qenable(WR(nextsib->sps_rq));
1258 			}
1259 		}
1260 		/*
1261 		 * Send useful information down to the modules which are now
1262 		 * linked below this driver (for this particular ppa). Only
1263 		 * do this if we are not the last PPP module on the stream.
1264 		 */
1265 		if (!IS_PPA_LASTMOD(ppa)) {
1266 			(void) putctl8(lwq, M_CTL, PPPCTL_UNIT,
1267 			    ppa->ppa_ppa_id);
1268 			(void) putctl4(lwq, M_CTL, PPPCTL_MRU, ppa->ppa_mru);
1269 			(void) putctl4(lwq, M_CTL, PPPCTL_MTU, ppa->ppa_mtu);
1270 		}
1271 
1272 		if (IS_SPS_KDEBUG(sps)) {
1273 			SPDEBUG(PPP_DRV_NAME
1274 			    "/%d: I_LINK lwq=0x%p sps=0x%p flags=0x%b ppa=0x%p "
1275 			    "flags=0x%b\n", sps->sps_mn_id,
1276 			    (void *)ppa->ppa_lower_wq, (void *)sps,
1277 			    sps->sps_flags, SPS_FLAGS_STR,
1278 			    (void *)ppa, ppa->ppa_flags,
1279 			    PPA_FLAGS_STR);
1280 		}
1281 		error = 0;		/* return success */
1282 		break;
1283 	case I_UNLINK:
1284 		ASSERT(IS_SPS_CONTROL(sps));
1285 		ASSERT(ppa != NULL);
1286 		lwq = ppa->ppa_lower_wq;
1287 		ASSERT(mp->b_cont != NULL && mp->b_cont->b_rptr != NULL);
1288 		ASSERT(lwq == ((struct linkblk *)mp->b_cont->b_rptr)->l_qbot);
1289 
1290 		if (IS_SPS_KDEBUG(sps)) {
1291 			SPDEBUG(PPP_DRV_NAME
1292 			    "/%d: I_UNLINK lwq=0x%p sps=0x%p flags=0x%b "
1293 			    "ppa=0x%p flags=0x%b\n", sps->sps_mn_id,
1294 			    (void *)lwq, (void *)sps, sps->sps_flags,
1295 			    SPS_FLAGS_STR, (void *)ppa, ppa->ppa_flags,
1296 			    PPA_FLAGS_STR);
1297 		}
1298 		/*
1299 		 * While accessing the outer perimeter exclusively, we
1300 		 * disassociate our ppa's lower_wq from the lower stream linked
1301 		 * beneath us, and we also disassociate our control stream from
1302 		 * the q_ptr of the lower stream.
1303 		 */
1304 		lwq->q_ptr = RD(lwq)->q_ptr = NULL;
1305 		ppa->ppa_lower_wq = NULL;
1306 		/*
1307 		 * Unblock streams which now feed back up the control stream,
1308 		 * and acknowledge the request. We don't need to hold
1309 		 * ppa_sib_lock here, since we are writer at the outer
1310 		 * perimeter.
1311 		 */
1312 		if (WR(sps->sps_rq)->q_first != NULL)
1313 			qenable(WR(sps->sps_rq));
1314 		for (nextsib = ppa->ppa_streams; nextsib != NULL;
1315 		    nextsib = nextsib->sps_nextsib) {
1316 			if (WR(nextsib->sps_rq)->q_first != NULL) {
1317 				qenable(WR(nextsib->sps_rq));
1318 			}
1319 		}
1320 		error = 0;		/* return success */
1321 		break;
1322 	case PPPIO_NEWPPA:
1323 		/*
1324 		 * Do sanity check to ensure that we don't accept PPPIO_NEWPPA
1325 		 * on a stream which DLPI is used (since certain DLPI messages
1326 		 * will cause state transition reflected in sps_dlstate,
1327 		 * changing it from its default DL_UNATTACHED value). In other
1328 		 * words, we won't allow a network/snoop stream to become
1329 		 * a control stream.
1330 		 */
1331 		if (iop->ioc_cr == NULL ||
1332 		    secpolicy_net_config(iop->ioc_cr, B_FALSE) != 0) {
1333 			error = EPERM;
1334 			break;
1335 		} else if (IS_SPS_CONTROL(sps) || IS_SPS_PIOATTACH(sps) ||
1336 		    (ppa != NULL) || (sps->sps_dlstate != DL_UNATTACHED)) {
1337 			break;		/* return EINVAL */
1338 		}
1339 		/* Get requested unit number (if any) */
1340 		if (iop->ioc_count == sizeof (uint32_t) && mp->b_cont != NULL)
1341 			ppa_id = *(uint32_t *)mp->b_cont->b_rptr;
1342 		else
1343 			ppa_id = 0;
1344 		/* Get mblk to use for response message */
1345 		nmp = allocb(sizeof (uint32_t), BPRI_MED);
1346 		if (nmp == NULL) {
1347 			error = ENOSR;
1348 			break;
1349 		}
1350 		if (mp->b_cont != NULL) {
1351 			freemsg(mp->b_cont);
1352 		}
1353 		mp->b_cont = nmp;		/* chain our response mblk */
1354 		/*
1355 		 * Walk the global ppa list and determine the lowest
1356 		 * available ppa_id number to be used.
1357 		 */
1358 		if (ppa_id == (uint32_t)-1)
1359 			ppa_id = 0;
1360 		for (ppa = ppa_list; ppa != NULL; ppa = ppa->ppa_nextppa) {
1361 			if (ppa_id == (uint32_t)-2) {
1362 				if (ppa->ppa_ctl == NULL)
1363 					break;
1364 			} else {
1365 				if (ppa_id < ppa->ppa_ppa_id)
1366 					break;
1367 				if (ppa_id == ppa->ppa_ppa_id)
1368 					++ppa_id;
1369 			}
1370 		}
1371 		if (ppa_id == (uint32_t)-2) {
1372 			if (ppa == NULL) {
1373 				error = ENXIO;
1374 				break;
1375 			}
1376 			/* Clear timestamp and lastmod flags */
1377 			ppa->ppa_flags = 0;
1378 		} else {
1379 			ppa = sppp_create_ppa(ppa_id);
1380 			if (ppa == NULL) {
1381 				error = ENOMEM;
1382 				break;
1383 			}
1384 		}
1385 
1386 		sps->sps_ppa = ppa;		/* chain the ppa structure */
1387 		sps->sps_npmode = NPMODE_PASS;	/* network packets may travel */
1388 		sps->sps_flags |= SPS_CONTROL;	/* this is the control stream */
1389 
1390 		ppa->ppa_refcnt++;		/* new PPA reference */
1391 		ppa->ppa_ctl = sps;		/* back ptr to upper stream */
1392 		/*
1393 		 * Return the newly created ppa_id to the requestor and
1394 		 * acnowledge the request.
1395 		 */
1396 		*(uint32_t *)nmp->b_wptr = ppa->ppa_ppa_id;
1397 		nmp->b_wptr += sizeof (uint32_t);
1398 
1399 		if (IS_SPS_KDEBUG(sps)) {
1400 			SPDEBUG(PPP_DRV_NAME
1401 			    "/%d: PPPIO_NEWPPA ppa_id=%d sps=0x%p flags=0x%b "
1402 			    "ppa=0x%p flags=0x%b\n", sps->sps_mn_id, ppa_id,
1403 			    (void *)sps, sps->sps_flags, SPS_FLAGS_STR,
1404 			    (void *)ppa, ppa->ppa_flags,
1405 			    PPA_FLAGS_STR);
1406 		}
1407 		count = msgsize(nmp);
1408 		error = 0;
1409 		break;
1410 	}
1411 
1412 	if (error == 0) {
1413 		/* Success; tell the user. */
1414 		miocack(q, mp, count, 0);
1415 	} else {
1416 		/* Failure; send error back upstream. */
1417 		miocnak(q, mp, 0, error);
1418 	}
1419 }
1420 
1421 /*
1422  * sppp_send()
1423  *
1424  * MT-Perimeters:
1425  *    shared inner, shared outer.
1426  *
1427  * Description:
1428  *    Called by sppp_uwput to handle M_DATA message type.  Returns
1429  *    queue_t for putnext, or NULL to mean that the packet was
1430  *    handled internally.
1431  */
1432 static queue_t *
1433 sppp_send(queue_t *q, mblk_t **mpp, spppstr_t *sps)
1434 {
1435 	mblk_t	*mp;
1436 	sppa_t	*ppa;
1437 	int	is_promisc;
1438 	int	msize;
1439 	int	error = 0;
1440 	queue_t	*nextq;
1441 
1442 	ASSERT(mpp != NULL);
1443 	mp = *mpp;
1444 	ASSERT(q != NULL && q->q_ptr != NULL);
1445 	ASSERT(mp != NULL && mp->b_rptr != NULL);
1446 	ASSERT(sps != NULL);
1447 	ASSERT(q->q_ptr == sps);
1448 	/*
1449 	 * We only let M_DATA through if the sender is either the control
1450 	 * stream (for PPP control packets) or one of the network streams
1451 	 * (for IP packets) in IP fastpath mode. If this stream is not attached
1452 	 * to any ppas, then discard data coming down through this stream.
1453 	 */
1454 	ppa = sps->sps_ppa;
1455 	if (ppa == NULL) {
1456 		ASSERT(!IS_SPS_CONTROL(sps));
1457 		error = ENOLINK;
1458 	} else if (!IS_SPS_CONTROL(sps) && !IS_SPS_FASTPATH(sps)) {
1459 		error = EPROTO;
1460 	}
1461 	if (error != 0) {
1462 		merror(q, mp, error);
1463 		return (NULL);
1464 	}
1465 	msize = msgdsize(mp);
1466 	if (msize > (ppa->ppa_mtu + PPP_HDRLEN)) {
1467 		/* Log, and send it anyway */
1468 		mutex_enter(&ppa->ppa_sta_lock);
1469 		ppa->ppa_otoolongs++;
1470 		mutex_exit(&ppa->ppa_sta_lock);
1471 	} else if (msize < PPP_HDRLEN) {
1472 		/*
1473 		 * Log, and send it anyway. We log it because we get things
1474 		 * in M_DATA form here, which tells us that the sender is
1475 		 * either IP in fastpath transmission mode, or pppd. In both
1476 		 * cases, they are currently expected to send the 4-bytes
1477 		 * PPP header in front of any possible payloads.
1478 		 */
1479 		mutex_enter(&ppa->ppa_sta_lock);
1480 		ppa->ppa_orunts++;
1481 		mutex_exit(&ppa->ppa_sta_lock);
1482 	}
1483 
1484 	if (IS_SPS_KDEBUG(sps)) {
1485 		SPDEBUG(PPP_DRV_NAME
1486 		    "/%d: M_DATA send (%d bytes) sps=0x%p flags=0x%b "
1487 		    "ppa=0x%p flags=0x%b\n", sps->sps_mn_id, msize,
1488 		    (void *)sps, sps->sps_flags, SPS_FLAGS_STR,
1489 		    (void *)ppa, ppa->ppa_flags, PPA_FLAGS_STR);
1490 	}
1491 	/*
1492 	 * Should there be any promiscuous stream(s), send the data up
1493 	 * for each promiscuous stream that we recognize. Make sure that
1494 	 * for fastpath, we skip the PPP header in the M_DATA mblk. We skip
1495 	 * the control stream as we obviously never allow the control stream
1496 	 * to become promiscous and bind to PPP_ALLSAP.
1497 	 */
1498 	rw_enter(&ppa->ppa_sib_lock, RW_READER);
1499 	is_promisc = sps->sps_ppa->ppa_promicnt;
1500 	if (is_promisc) {
1501 		ASSERT(ppa->ppa_streams != NULL);
1502 		sppp_dlprsendup(ppa->ppa_streams, mp, sps->sps_sap, B_TRUE);
1503 	}
1504 	rw_exit(&ppa->ppa_sib_lock);
1505 	/*
1506 	 * Only time-stamp the packet with hrtime if the upper stream
1507 	 * is configured to do so.  PPP control (negotiation) messages
1508 	 * are never considered link activity; only data is activity.
1509 	 */
1510 	if (!IS_SPS_CONTROL(sps) && IS_PPA_TIMESTAMP(ppa)) {
1511 		ppa->ppa_lasttx = gethrtime();
1512 	}
1513 	/*
1514 	 * If there's already a message in the write-side service queue,
1515 	 * then queue this message there as well, otherwise, try to send
1516 	 * it down to the module immediately below us.
1517 	 */
1518 	if (q->q_first != NULL ||
1519 	    (nextq = sppp_outpkt(q, mpp, msize, sps)) == NULL) {
1520 		mp = *mpp;
1521 		if (mp != NULL && putq(q, mp) == 0) {
1522 			mutex_enter(&ppa->ppa_sta_lock);
1523 			ppa->ppa_oqdropped++;
1524 			mutex_exit(&ppa->ppa_sta_lock);
1525 			freemsg(mp);
1526 		}
1527 		return (NULL);
1528 	}
1529 	return (nextq);
1530 }
1531 
1532 /*
1533  * sppp_outpkt()
1534  *
1535  * MT-Perimeters:
1536  *    shared inner, shared outer (if called from sppp_wput, sppp_dlunitdatareq).
1537  *    exclusive inner, shared outer (if called from sppp_wsrv).
1538  *
1539  * Description:
1540  *    Called from 1) sppp_uwput when processing a M_DATA fastpath message,
1541  *    or 2) sppp_uwsrv when processing the upper write-side service queue.
1542  *    For both cases, it prepares to send the data to the module below
1543  *    this driver if there is a lower stream linked underneath. If none, then
1544  *    the data will be sent upstream via the control channel to pppd.
1545  *
1546  * Returns:
1547  *	Non-NULL queue_t if message should be sent now, otherwise
1548  *	if *mpp == NULL, then message was freed, otherwise put *mpp
1549  *	(back) on the queue.  (Does not do putq/putbq, since it's
1550  *	called both from srv and put procedures.)
1551  */
1552 static queue_t *
1553 sppp_outpkt(queue_t *q, mblk_t **mpp, int msize, spppstr_t *sps)
1554 {
1555 	mblk_t		*mp;
1556 	sppa_t		*ppa;
1557 	enum NPmode	npmode;
1558 	mblk_t		*mpnew;
1559 
1560 	ASSERT(mpp != NULL);
1561 	mp = *mpp;
1562 	ASSERT(q != NULL && q->q_ptr != NULL);
1563 	ASSERT(mp != NULL && mp->b_rptr != NULL);
1564 	ASSERT(sps != NULL);
1565 
1566 	ppa = sps->sps_ppa;
1567 	npmode = sps->sps_npmode;
1568 
1569 	if (npmode == NPMODE_QUEUE) {
1570 		ASSERT(!IS_SPS_CONTROL(sps));
1571 		return (NULL);	/* queue it for later */
1572 	} else if (ppa == NULL || ppa->ppa_ctl == NULL ||
1573 	    npmode == NPMODE_DROP || npmode == NPMODE_ERROR) {
1574 		/*
1575 		 * This can not be the control stream, as it must always have
1576 		 * a valid ppa, and its npmode must always be NPMODE_PASS.
1577 		 */
1578 		ASSERT(!IS_SPS_CONTROL(sps));
1579 		if (npmode == NPMODE_DROP) {
1580 			freemsg(mp);
1581 		} else {
1582 			/*
1583 			 * If we no longer have the control stream, or if the
1584 			 * mode is set to NPMODE_ERROR, then we need to tell IP
1585 			 * that the interface need to be marked as down. In
1586 			 * other words, we tell IP to be quiescent.
1587 			 */
1588 			merror(q, mp, EPROTO);
1589 		}
1590 		*mpp = NULL;
1591 		return (NULL);	/* don't queue it */
1592 	}
1593 	/*
1594 	 * Do we have a driver stream linked underneath ? If not, we need to
1595 	 * notify pppd that the link needs to be brought up and configure
1596 	 * this upper stream to drop subsequent outgoing packets. This is
1597 	 * for demand-dialing, in which case pppd has done the IP plumbing
1598 	 * but hasn't linked the driver stream underneath us. Therefore, when
1599 	 * a packet is sent down the IP interface, a notification message
1600 	 * will be sent up the control stream to pppd in order for it to
1601 	 * establish the physical link. The driver stream is then expected
1602 	 * to be linked underneath after physical link establishment is done.
1603 	 */
1604 	if (ppa->ppa_lower_wq == NULL) {
1605 		ASSERT(ppa->ppa_ctl != NULL);
1606 		ASSERT(ppa->ppa_ctl->sps_rq != NULL);
1607 
1608 		*mpp = NULL;
1609 		mpnew = create_lsmsg(PPP_LINKSTAT_NEEDUP);
1610 		if (mpnew == NULL) {
1611 			freemsg(mp);
1612 			mutex_enter(&ppa->ppa_sta_lock);
1613 			ppa->ppa_allocbfail++;
1614 			mutex_exit(&ppa->ppa_sta_lock);
1615 			return (NULL);	/* don't queue it */
1616 		}
1617 		/* Include the data in the message for logging. */
1618 		mpnew->b_cont = mp;
1619 		mutex_enter(&ppa->ppa_sta_lock);
1620 		ppa->ppa_lsneedup++;
1621 		mutex_exit(&ppa->ppa_sta_lock);
1622 		/*
1623 		 * We need to set the mode to NPMODE_DROP, but should only
1624 		 * do so when this stream is not the control stream.
1625 		 */
1626 		if (!IS_SPS_CONTROL(sps)) {
1627 			sps->sps_npmode = NPMODE_DROP;
1628 		}
1629 		putnext(ppa->ppa_ctl->sps_rq, mpnew);
1630 		return (NULL);	/* don't queue it */
1631 	}
1632 	/*
1633 	 * If so, then try to send it down. The lower queue is only ever
1634 	 * detached while holding an exclusive lock on the whole driver,
1635 	 * so we can be confident that the lower queue is still there.
1636 	 */
1637 	if (bcanputnext(ppa->ppa_lower_wq, mp->b_band)) {
1638 		mutex_enter(&ppa->ppa_sta_lock);
1639 		ppa->ppa_stats.p.ppp_opackets++;
1640 		if (IS_SPS_CONTROL(sps)) {
1641 			ppa->ppa_opkt_ctl++;
1642 		}
1643 		ppa->ppa_stats.p.ppp_obytes += msize;
1644 		mutex_exit(&ppa->ppa_sta_lock);
1645 		return (ppa->ppa_lower_wq);	/* don't queue it */
1646 	}
1647 	return (NULL);	/* queue it for later */
1648 }
1649 
1650 /*
1651  * sppp_lwsrv()
1652  *
1653  * MT-Perimeters:
1654  *    exclusive inner, shared outer.
1655  *
1656  * Description:
1657  *    Lower write-side service procedure. No messages are ever placed on
1658  *    the write queue here, this just back-enables all upper write side
1659  *    service procedures.
1660  */
1661 int
1662 sppp_lwsrv(queue_t *q)
1663 {
1664 	sppa_t		*ppa;
1665 	spppstr_t	*nextsib;
1666 
1667 	ASSERT(q != NULL && q->q_ptr != NULL);
1668 	ppa = (sppa_t *)q->q_ptr;
1669 	ASSERT(ppa != NULL);
1670 
1671 	rw_enter(&ppa->ppa_sib_lock, RW_READER);
1672 	if ((nextsib = ppa->ppa_ctl) != NULL &&
1673 	    WR(nextsib->sps_rq)->q_first != NULL)
1674 		qenable(WR(nextsib->sps_rq));
1675 	for (nextsib = ppa->ppa_streams; nextsib != NULL;
1676 	    nextsib = nextsib->sps_nextsib) {
1677 		if (WR(nextsib->sps_rq)->q_first != NULL) {
1678 			qenable(WR(nextsib->sps_rq));
1679 		}
1680 	}
1681 	rw_exit(&ppa->ppa_sib_lock);
1682 	return (0);
1683 }
1684 
1685 /*
1686  * sppp_lrput()
1687  *
1688  * MT-Perimeters:
1689  *    shared inner, shared outer.
1690  *
1691  * Description:
1692  *    Lower read-side put procedure. Messages from below get here.
1693  *    Data messages are handled separately to limit stack usage
1694  *    going into IP.
1695  */
1696 int
1697 sppp_lrput(queue_t *q, mblk_t *mp)
1698 {
1699 	sppa_t		*ppa;
1700 	spppstr_t	*sps;
1701 
1702 	ppa = (sppa_t *)q->q_ptr;
1703 	sps = ppa->ppa_ctl;
1704 
1705 	if (MTYPE(mp) != M_DATA) {
1706 		sppp_recv_nondata(q, mp, sps);
1707 	} else if (sps == NULL) {
1708 		freemsg(mp);
1709 	} else if ((q = sppp_recv(q, &mp, sps)) != NULL) {
1710 		putnext(q, mp);
1711 	}
1712 	return (0);
1713 }
1714 
1715 /*
1716  * sppp_recv_nondata()
1717  *
1718  * MT-Perimeters:
1719  *    shared inner, shared outer.
1720  *
1721  * Description:
1722  *    All received non-data messages come through here.
1723  */
1724 static void
1725 sppp_recv_nondata(queue_t *q, mblk_t *mp, spppstr_t *ctlsps)
1726 {
1727 	sppa_t		*ppa;
1728 	spppstr_t	*destsps;
1729 	struct iocblk	*iop;
1730 
1731 	ppa = (sppa_t *)q->q_ptr;
1732 	ctlsps = ppa->ppa_ctl;
1733 
1734 	switch (MTYPE(mp)) {
1735 	case M_CTL:
1736 		mutex_enter(&ppa->ppa_sta_lock);
1737 		if (*mp->b_rptr == PPPCTL_IERROR) {
1738 			ppa->ppa_stats.p.ppp_ierrors++;
1739 			ppa->ppa_ierr_low++;
1740 			ppa->ppa_mctlsknown++;
1741 		} else if (*mp->b_rptr == PPPCTL_OERROR) {
1742 			ppa->ppa_stats.p.ppp_oerrors++;
1743 			ppa->ppa_oerr_low++;
1744 			ppa->ppa_mctlsknown++;
1745 		} else {
1746 			ppa->ppa_mctlsunknown++;
1747 		}
1748 		mutex_exit(&ppa->ppa_sta_lock);
1749 		freemsg(mp);
1750 		break;
1751 	case M_IOCTL:
1752 		miocnak(q, mp, 0, EINVAL);
1753 		break;
1754 	case M_IOCACK:
1755 	case M_IOCNAK:
1756 		iop = (struct iocblk *)mp->b_rptr;
1757 		ASSERT(iop != NULL);
1758 		/*
1759 		 * Attempt to match up the response with the stream that the
1760 		 * request came from. If ioc_id doesn't match the one that we
1761 		 * recorded, then discard this message.
1762 		 */
1763 		rw_enter(&ppa->ppa_sib_lock, RW_READER);
1764 		if ((destsps = ctlsps) == NULL ||
1765 		    destsps->sps_ioc_id != iop->ioc_id) {
1766 			destsps = ppa->ppa_streams;
1767 			while (destsps != NULL) {
1768 				if (destsps->sps_ioc_id == iop->ioc_id) {
1769 					break;	/* found the upper stream */
1770 				}
1771 				destsps = destsps->sps_nextsib;
1772 			}
1773 		}
1774 		rw_exit(&ppa->ppa_sib_lock);
1775 		if (destsps == NULL) {
1776 			mutex_enter(&ppa->ppa_sta_lock);
1777 			ppa->ppa_ioctlsfwderr++;
1778 			mutex_exit(&ppa->ppa_sta_lock);
1779 			freemsg(mp);
1780 			break;
1781 		}
1782 		mutex_enter(&ppa->ppa_sta_lock);
1783 		ppa->ppa_ioctlsfwdok++;
1784 		mutex_exit(&ppa->ppa_sta_lock);
1785 		putnext(destsps->sps_rq, mp);
1786 		break;
1787 	case M_HANGUP:
1788 		/*
1789 		 * Free the original mblk_t. We don't really want to send
1790 		 * a M_HANGUP message upstream, so we need to translate this
1791 		 * message into something else.
1792 		 */
1793 		freemsg(mp);
1794 		if (ctlsps == NULL)
1795 			break;
1796 		mp = create_lsmsg(PPP_LINKSTAT_HANGUP);
1797 		if (mp == NULL) {
1798 			mutex_enter(&ppa->ppa_sta_lock);
1799 			ppa->ppa_allocbfail++;
1800 			mutex_exit(&ppa->ppa_sta_lock);
1801 			break;
1802 		}
1803 		mutex_enter(&ppa->ppa_sta_lock);
1804 		ppa->ppa_lsdown++;
1805 		mutex_exit(&ppa->ppa_sta_lock);
1806 		putnext(ctlsps->sps_rq, mp);
1807 		break;
1808 	case M_FLUSH:
1809 		if (*mp->b_rptr & FLUSHR) {
1810 			flushq(q, FLUSHDATA);
1811 		}
1812 		if (*mp->b_rptr & FLUSHW) {
1813 			*mp->b_rptr &= ~FLUSHR;
1814 			qreply(q, mp);
1815 		} else {
1816 			freemsg(mp);
1817 		}
1818 		break;
1819 	default:
1820 		if (ctlsps != NULL &&
1821 		    (queclass(mp) == QPCTL) || canputnext(ctlsps->sps_rq)) {
1822 			putnext(ctlsps->sps_rq, mp);
1823 		} else {
1824 			mutex_enter(&ppa->ppa_sta_lock);
1825 			ppa->ppa_iqdropped++;
1826 			mutex_exit(&ppa->ppa_sta_lock);
1827 			freemsg(mp);
1828 		}
1829 		break;
1830 	}
1831 }
1832 
1833 /*
1834  * sppp_recv()
1835  *
1836  * MT-Perimeters:
1837  *    shared inner, shared outer.
1838  *
1839  * Description:
1840  *    Receive function called by sppp_lrput.  Finds appropriate
1841  *    receive stream and does accounting.
1842  */
1843 static queue_t *
1844 sppp_recv(queue_t *q, mblk_t **mpp, spppstr_t *ctlsps)
1845 {
1846 	mblk_t		*mp;
1847 	int		len;
1848 	sppa_t		*ppa;
1849 	spppstr_t	*destsps;
1850 	mblk_t		*zmp;
1851 	uint32_t	npflagpos;
1852 
1853 	ASSERT(mpp != NULL);
1854 	mp = *mpp;
1855 	ASSERT(q != NULL && q->q_ptr != NULL);
1856 	ASSERT(mp != NULL && mp->b_rptr != NULL);
1857 	ASSERT(ctlsps != NULL);
1858 	ASSERT(IS_SPS_CONTROL(ctlsps));
1859 	ppa = ctlsps->sps_ppa;
1860 	ASSERT(ppa != NULL && ppa->ppa_ctl != NULL);
1861 
1862 	len = msgdsize(mp);
1863 	mutex_enter(&ppa->ppa_sta_lock);
1864 	ppa->ppa_stats.p.ppp_ibytes += len;
1865 	mutex_exit(&ppa->ppa_sta_lock);
1866 	/*
1867 	 * If the entire data size of the mblk is less than the length of the
1868 	 * PPP header, then free it. We can't do much with such message anyway,
1869 	 * since we can't really determine what the PPP protocol type is.
1870 	 */
1871 	if (len < PPP_HDRLEN) {
1872 		/* Log, and free it */
1873 		mutex_enter(&ppa->ppa_sta_lock);
1874 		ppa->ppa_irunts++;
1875 		mutex_exit(&ppa->ppa_sta_lock);
1876 		freemsg(mp);
1877 		return (NULL);
1878 	} else if (len > (ppa->ppa_mru + PPP_HDRLEN)) {
1879 		/* Log, and accept it anyway */
1880 		mutex_enter(&ppa->ppa_sta_lock);
1881 		ppa->ppa_itoolongs++;
1882 		mutex_exit(&ppa->ppa_sta_lock);
1883 	}
1884 	/*
1885 	 * We need at least be able to read the PPP protocol from the header,
1886 	 * so if the first message block is too small, then we concatenate the
1887 	 * rest of the following blocks into one message.
1888 	 */
1889 	if (MBLKL(mp) < PPP_HDRLEN) {
1890 		zmp = msgpullup(mp, PPP_HDRLEN);
1891 		freemsg(mp);
1892 		mp = zmp;
1893 		if (mp == NULL) {
1894 			mutex_enter(&ppa->ppa_sta_lock);
1895 			ppa->ppa_allocbfail++;
1896 			mutex_exit(&ppa->ppa_sta_lock);
1897 			return (NULL);
1898 		}
1899 		*mpp = mp;
1900 	}
1901 	/*
1902 	 * Hold this packet in the control-queue until
1903 	 * the matching network-layer upper stream for the PPP protocol (sap)
1904 	 * has not been plumbed and configured
1905 	 */
1906 	npflagpos = sppp_ppp2np(PPP_PROTOCOL(mp->b_rptr));
1907 	mutex_enter(&ppa->ppa_npmutex);
1908 	if (npflagpos != 0 && (ppa->ppa_npflag & (1 << npflagpos))) {
1909 		/*
1910 		 * proto is currently blocked; Hold up to 4 packets
1911 		 * in the kernel.
1912 		 */
1913 		if (ppa->ppa_holdpkts[npflagpos] > 3 ||
1914 		    putq(ctlsps->sps_rq, mp) == 0)
1915 			freemsg(mp);
1916 		else
1917 			ppa->ppa_holdpkts[npflagpos]++;
1918 		mutex_exit(&ppa->ppa_npmutex);
1919 		return (NULL);
1920 	}
1921 	mutex_exit(&ppa->ppa_npmutex);
1922 	/*
1923 	 * Try to find a matching network-layer upper stream for the specified
1924 	 * PPP protocol (sap), and if none is found, send this frame up the
1925 	 * control stream.
1926 	 */
1927 	destsps = sppp_inpkt(q, mp, ctlsps);
1928 	if (destsps == NULL) {
1929 		mutex_enter(&ppa->ppa_sta_lock);
1930 		ppa->ppa_ipkt_ctl++;
1931 		mutex_exit(&ppa->ppa_sta_lock);
1932 		if (canputnext(ctlsps->sps_rq)) {
1933 			if (IS_SPS_KDEBUG(ctlsps)) {
1934 				SPDEBUG(PPP_DRV_NAME
1935 				    "/%d: M_DATA recv (%d bytes) sps=0x%p "
1936 				    "flags=0x%b ppa=0x%p flags=0x%b\n",
1937 				    ctlsps->sps_mn_id, len, (void *)ctlsps,
1938 				    ctlsps->sps_flags, SPS_FLAGS_STR,
1939 				    (void *)ppa, ppa->ppa_flags,
1940 				    PPA_FLAGS_STR);
1941 			}
1942 			return (ctlsps->sps_rq);
1943 		} else {
1944 			mutex_enter(&ppa->ppa_sta_lock);
1945 			ppa->ppa_iqdropped++;
1946 			mutex_exit(&ppa->ppa_sta_lock);
1947 			freemsg(mp);
1948 			return (NULL);
1949 		}
1950 	}
1951 	if (canputnext(destsps->sps_rq)) {
1952 		if (IS_SPS_KDEBUG(destsps)) {
1953 			SPDEBUG(PPP_DRV_NAME
1954 			    "/%d: M_DATA recv (%d bytes) sps=0x%p flags=0x%b "
1955 			    "ppa=0x%p flags=0x%b\n", destsps->sps_mn_id, len,
1956 			    (void *)destsps, destsps->sps_flags,
1957 			    SPS_FLAGS_STR, (void *)ppa, ppa->ppa_flags,
1958 			    PPA_FLAGS_STR);
1959 		}
1960 		/*
1961 		 * If fastpath is enabled on the network-layer stream, then
1962 		 * make sure we skip over the PPP header, otherwise, we wrap
1963 		 * the message in a DLPI message.
1964 		 */
1965 		if (IS_SPS_FASTPATH(destsps)) {
1966 			mp->b_rptr += PPP_HDRLEN;
1967 			return (destsps->sps_rq);
1968 		} else {
1969 			spppstr_t *uqs = (spppstr_t *)destsps->sps_rq->q_ptr;
1970 			ASSERT(uqs != NULL);
1971 			mp->b_rptr += PPP_HDRLEN;
1972 			mp = sppp_dladdud(uqs, mp, uqs->sps_sap, B_FALSE);
1973 			if (mp != NULL) {
1974 				*mpp = mp;
1975 				return (destsps->sps_rq);
1976 			} else {
1977 				mutex_enter(&ppa->ppa_sta_lock);
1978 				ppa->ppa_allocbfail++;
1979 				mutex_exit(&ppa->ppa_sta_lock);
1980 				/* mp already freed by sppp_dladdud */
1981 				return (NULL);
1982 			}
1983 		}
1984 	} else {
1985 		mutex_enter(&ppa->ppa_sta_lock);
1986 		ppa->ppa_iqdropped++;
1987 		mutex_exit(&ppa->ppa_sta_lock);
1988 		freemsg(mp);
1989 		return (NULL);
1990 	}
1991 }
1992 
1993 /*
1994  * sppp_inpkt()
1995  *
1996  * MT-Perimeters:
1997  *    shared inner, shared outer.
1998  *
1999  * Description:
2000  *    Find the destination upper stream for the received packet, called
2001  *    from sppp_recv.
2002  *
2003  * Returns:
2004  *    ptr to destination upper network stream, or NULL for control stream.
2005  */
2006 /* ARGSUSED */
2007 static spppstr_t *
2008 sppp_inpkt(queue_t *q, mblk_t *mp, spppstr_t *ctlsps)
2009 {
2010 	spppstr_t	*destsps = NULL;
2011 	sppa_t		*ppa;
2012 	uint16_t	proto;
2013 	int		is_promisc;
2014 
2015 	ASSERT(q != NULL && q->q_ptr != NULL);
2016 	ASSERT(mp != NULL && mp->b_rptr != NULL);
2017 	ASSERT(IS_SPS_CONTROL(ctlsps));
2018 	ppa = ctlsps->sps_ppa;
2019 	ASSERT(ppa != NULL);
2020 	/*
2021 	 * From RFC 1661 (Section 2):
2022 	 *
2023 	 * The Protocol field is one or two octets, and its value identifies
2024 	 * the datagram encapsulated in the Information field of the packet.
2025 	 * The field is transmitted and received most significant octet first.
2026 	 *
2027 	 * The structure of this field is consistent with the ISO 3309
2028 	 * extension mechanism for address fields.  All Protocols MUST be odd;
2029 	 * the least significant bit of the least significant octet MUST equal
2030 	 * "1".  Also, all Protocols MUST be assigned such that the least
2031 	 * significant bit of the most significant octet equals "0". Frames
2032 	 * received which don't comply with these rules MUST be treated as
2033 	 * having an unrecognized Protocol.
2034 	 *
2035 	 * Protocol field values in the "0***" to "3***" range identify the
2036 	 * network-layer protocol of specific packets, and values in the
2037 	 * "8***" to "b***" range identify packets belonging to the associated
2038 	 * Network Control Protocols (NCPs), if any.
2039 	 *
2040 	 * Protocol field values in the "4***" to "7***" range are used for
2041 	 * protocols with low volume traffic which have no associated NCP.
2042 	 * Protocol field values in the "c***" to "f***" range identify packets
2043 	 * as link-layer Control Protocols (such as LCP).
2044 	 */
2045 	proto = PPP_PROTOCOL(mp->b_rptr);
2046 	mutex_enter(&ppa->ppa_sta_lock);
2047 	ppa->ppa_stats.p.ppp_ipackets++;
2048 	mutex_exit(&ppa->ppa_sta_lock);
2049 	/*
2050 	 * We check if this is not a network-layer protocol, and if so,
2051 	 * then send this packet up the control stream.
2052 	 */
2053 	if (proto > 0x7fff) {
2054 		goto inpkt_done;	/* send it up the control stream */
2055 	}
2056 	/*
2057 	 * Try to grab the destination upper stream from the network-layer
2058 	 * stream cache for this ppa for PPP_IP (0x0021) or PPP_IPV6 (0x0057)
2059 	 * protocol types. Otherwise, if the type is not known to the cache,
2060 	 * or if its sap can't be matched with any of the upper streams, then
2061 	 * send this packet up the control stream so that it can be rejected.
2062 	 */
2063 	if (proto == PPP_IP) {
2064 		destsps = ppa->ppa_ip_cache;
2065 	} else if (proto == PPP_IPV6) {
2066 		destsps = ppa->ppa_ip6_cache;
2067 	}
2068 	/*
2069 	 * Toss this one away up the control stream if there's no matching sap;
2070 	 * this way the protocol can be rejected (destsps is NULL).
2071 	 */
2072 
2073 inpkt_done:
2074 	/*
2075 	 * Only time-stamp the packet with hrtime if the upper stream
2076 	 * is configured to do so.  PPP control (negotiation) messages
2077 	 * are never considered link activity; only data is activity.
2078 	 */
2079 	if (destsps != NULL && IS_PPA_TIMESTAMP(ppa)) {
2080 		ppa->ppa_lastrx = gethrtime();
2081 	}
2082 	/*
2083 	 * Should there be any promiscuous stream(s), send the data up for
2084 	 * each promiscuous stream that we recognize. We skip the control
2085 	 * stream as we obviously never allow the control stream to become
2086 	 * promiscous and bind to PPP_ALLSAP.
2087 	 */
2088 	rw_enter(&ppa->ppa_sib_lock, RW_READER);
2089 	is_promisc = ppa->ppa_promicnt;
2090 	if (is_promisc) {
2091 		ASSERT(ppa->ppa_streams != NULL);
2092 		sppp_dlprsendup(ppa->ppa_streams, mp, proto, B_TRUE);
2093 	}
2094 	rw_exit(&ppa->ppa_sib_lock);
2095 	return (destsps);
2096 }
2097 
2098 /*
2099  * sppp_kstat_update()
2100  *
2101  * Description:
2102  *    Update per-ppa kstat interface statistics.
2103  */
2104 static int
2105 sppp_kstat_update(kstat_t *ksp, int rw)
2106 {
2107 	register sppa_t		*ppa;
2108 	register sppp_kstats_t	*pppkp;
2109 	register struct pppstat64 *sp;
2110 
2111 	if (rw == KSTAT_WRITE) {
2112 		return (EACCES);
2113 	}
2114 
2115 	ppa = (sppa_t *)ksp->ks_private;
2116 	ASSERT(ppa != NULL);
2117 
2118 	pppkp = (sppp_kstats_t *)ksp->ks_data;
2119 	sp = &ppa->ppa_stats.p;
2120 
2121 	mutex_enter(&ppa->ppa_sta_lock);
2122 	pppkp->allocbfail.value.ui32	= ppa->ppa_allocbfail;
2123 	pppkp->mctlsfwd.value.ui32	= ppa->ppa_mctlsfwd;
2124 	pppkp->mctlsfwderr.value.ui32	= ppa->ppa_mctlsfwderr;
2125 	pppkp->rbytes.value.ui32	= sp->ppp_ibytes;
2126 	pppkp->rbytes64.value.ui64	= sp->ppp_ibytes;
2127 	pppkp->ierrors.value.ui32	= sp->ppp_ierrors;
2128 	pppkp->ierrors_lower.value.ui32	= ppa->ppa_ierr_low;
2129 	pppkp->ioctlsfwd.value.ui32	= ppa->ppa_ioctlsfwd;
2130 	pppkp->ioctlsfwdok.value.ui32	= ppa->ppa_ioctlsfwdok;
2131 	pppkp->ioctlsfwderr.value.ui32	= ppa->ppa_ioctlsfwderr;
2132 	pppkp->ipackets.value.ui32	= sp->ppp_ipackets;
2133 	pppkp->ipackets64.value.ui64	= sp->ppp_ipackets;
2134 	pppkp->ipackets_ctl.value.ui32	= ppa->ppa_ipkt_ctl;
2135 	pppkp->iqdropped.value.ui32	= ppa->ppa_iqdropped;
2136 	pppkp->irunts.value.ui32	= ppa->ppa_irunts;
2137 	pppkp->itoolongs.value.ui32	= ppa->ppa_itoolongs;
2138 	pppkp->lsneedup.value.ui32	= ppa->ppa_lsneedup;
2139 	pppkp->lsdown.value.ui32	= ppa->ppa_lsdown;
2140 	pppkp->mctlsknown.value.ui32	= ppa->ppa_mctlsknown;
2141 	pppkp->mctlsunknown.value.ui32	= ppa->ppa_mctlsunknown;
2142 	pppkp->obytes.value.ui32	= sp->ppp_obytes;
2143 	pppkp->obytes64.value.ui64	= sp->ppp_obytes;
2144 	pppkp->oerrors.value.ui32	= sp->ppp_oerrors;
2145 	pppkp->oerrors_lower.value.ui32	= ppa->ppa_oerr_low;
2146 	pppkp->opackets.value.ui32	= sp->ppp_opackets;
2147 	pppkp->opackets64.value.ui64	= sp->ppp_opackets;
2148 	pppkp->opackets_ctl.value.ui32	= ppa->ppa_opkt_ctl;
2149 	pppkp->oqdropped.value.ui32	= ppa->ppa_oqdropped;
2150 	pppkp->otoolongs.value.ui32	= ppa->ppa_otoolongs;
2151 	pppkp->orunts.value.ui32	= ppa->ppa_orunts;
2152 	mutex_exit(&ppa->ppa_sta_lock);
2153 
2154 	return (0);
2155 }
2156 
2157 /*
2158  * Turn off proto in ppa_npflag to indicate that
2159  * the corresponding network protocol has been plumbed.
2160  * Release proto packets that were being held in the control
2161  * queue in anticipation of this event.
2162  */
2163 static void
2164 sppp_release_pkts(sppa_t *ppa, uint16_t proto)
2165 {
2166 	uint32_t npflagpos = sppp_ppp2np(proto);
2167 	int count;
2168 	mblk_t *mp;
2169 	uint16_t mp_proto;
2170 	queue_t *q;
2171 	spppstr_t *destsps;
2172 
2173 	ASSERT(ppa != NULL);
2174 
2175 	if (npflagpos == 0 || (ppa->ppa_npflag & (1 << npflagpos)) == 0)
2176 		return;
2177 
2178 	mutex_enter(&ppa->ppa_npmutex);
2179 	ppa->ppa_npflag &= ~(1 << npflagpos);
2180 	count = ppa->ppa_holdpkts[npflagpos];
2181 	ppa->ppa_holdpkts[npflagpos] = 0;
2182 	mutex_exit(&ppa->ppa_npmutex);
2183 
2184 	q = ppa->ppa_ctl->sps_rq;
2185 
2186 	while (count > 0) {
2187 		mp = getq(q);
2188 		ASSERT(mp != NULL);
2189 
2190 		mp_proto = PPP_PROTOCOL(mp->b_rptr);
2191 		if (mp_proto !=  proto) {
2192 			(void) putq(q, mp);
2193 			continue;
2194 		}
2195 		count--;
2196 		destsps = NULL;
2197 		if (mp_proto == PPP_IP) {
2198 			destsps = ppa->ppa_ip_cache;
2199 		} else if (mp_proto == PPP_IPV6) {
2200 			destsps = ppa->ppa_ip6_cache;
2201 		}
2202 		ASSERT(destsps != NULL);
2203 
2204 		if (IS_SPS_FASTPATH(destsps)) {
2205 			mp->b_rptr += PPP_HDRLEN;
2206 		} else {
2207 			spppstr_t *uqs = (spppstr_t *)destsps->sps_rq->q_ptr;
2208 			ASSERT(uqs != NULL);
2209 			mp->b_rptr += PPP_HDRLEN;
2210 			mp = sppp_dladdud(uqs, mp, uqs->sps_sap, B_FALSE);
2211 			if (mp == NULL) {
2212 				mutex_enter(&ppa->ppa_sta_lock);
2213 				ppa->ppa_allocbfail++;
2214 				mutex_exit(&ppa->ppa_sta_lock);
2215 				/* mp already freed by sppp_dladdud */
2216 				continue;
2217 			}
2218 		}
2219 
2220 		if (canputnext(destsps->sps_rq)) {
2221 			putnext(destsps->sps_rq, mp);
2222 		} else {
2223 			mutex_enter(&ppa->ppa_sta_lock);
2224 			ppa->ppa_iqdropped++;
2225 			mutex_exit(&ppa->ppa_sta_lock);
2226 			freemsg(mp);
2227 			continue;
2228 		}
2229 	}
2230 }
2231