xref: /netbsd-src/sys/net/if_ppp.c (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
1 /*	$NetBSD: if_ppp.c,v 1.149 2015/08/24 22:21:26 pooka Exp $	*/
2 /*	Id: if_ppp.c,v 1.6 1997/03/04 03:33:00 paulus Exp 	*/
3 
4 /*
5  * if_ppp.c - Point-to-Point Protocol (PPP) Asynchronous driver.
6  *
7  * Copyright (c) 1984-2000 Carnegie Mellon University. All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  *
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in
18  *    the documentation and/or other materials provided with the
19  *    distribution.
20  *
21  * 3. The name "Carnegie Mellon University" must not be used to
22  *    endorse or promote products derived from this software without
23  *    prior written permission. For permission or any legal
24  *    details, please contact
25  *      Office of Technology Transfer
26  *      Carnegie Mellon University
27  *      5000 Forbes Avenue
28  *      Pittsburgh, PA  15213-3890
29  *      (412) 268-4387, fax: (412) 268-7395
30  *      tech-transfer@andrew.cmu.edu
31  *
32  * 4. Redistributions of any form whatsoever must retain the following
33  *    acknowledgment:
34  *    "This product includes software developed by Computing Services
35  *     at Carnegie Mellon University (http://www.cmu.edu/computing/)."
36  *
37  * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
38  * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
39  * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
40  * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
41  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
42  * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
43  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
44  *
45  * Based on:
46  *	@(#)if_sl.c	7.6.1.2 (Berkeley) 2/15/89
47  *
48  * Copyright (c) 1987 Regents of the University of California.
49  * All rights reserved.
50  *
51  * Redistribution and use in source and binary forms are permitted
52  * provided that the above copyright notice and this paragraph are
53  * duplicated in all such forms and that any documentation,
54  * advertising materials, and other materials related to such
55  * distribution and use acknowledge that the software was developed
56  * by the University of California, Berkeley.  The name of the
57  * University may not be used to endorse or promote products derived
58  * from this software without specific prior written permission.
59  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
60  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
61  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
62  *
63  * Serial Line interface
64  *
65  * Rick Adams
66  * Center for Seismic Studies
67  * 1300 N 17th Street, Suite 1450
68  * Arlington, Virginia 22209
69  * (703)276-7900
70  * rick@seismo.ARPA
71  * seismo!rick
72  *
73  * Pounded on heavily by Chris Torek (chris@mimsy.umd.edu, umcp-cs!chris).
74  * Converted to 4.3BSD Beta by Chris Torek.
75  * Other changes made at Berkeley, based in part on code by Kirk Smith.
76  *
77  * Converted to 4.3BSD+ 386BSD by Brad Parker (brad@cayman.com)
78  * Added VJ tcp header compression; more unified ioctls
79  *
80  * Extensively modified by Paul Mackerras (paulus@cs.anu.edu.au).
81  * Cleaned up a lot of the mbuf-related code to fix bugs that
82  * caused system crashes and packet corruption.  Changed pppstart
83  * so that it doesn't just give up with a collision if the whole
84  * packet doesn't fit in the output ring buffer.
85  *
86  * Added priority queueing for interactive IP packets, following
87  * the model of if_sl.c, plus hooks for bpf.
88  * Paul Mackerras (paulus@cs.anu.edu.au).
89  */
90 
91 /* from if_sl.c,v 1.11 84/10/04 12:54:47 rick Exp */
92 /* from NetBSD: if_ppp.c,v 1.15.2.2 1994/07/28 05:17:58 cgd Exp */
93 
94 /*
95  * XXX IMP ME HARDER
96  *
97  * This is an explanation of that comment.  This code used to use
98  * splimp() to block both network and tty interrupts.  However,
99  * that call is deprecated.  So, we have replaced the uses of
100  * splimp() with splhigh() in order to applomplish what it needs
101  * to accomplish, and added that happy little comment.
102  */
103 
104 #include <sys/cdefs.h>
105 __KERNEL_RCSID(0, "$NetBSD: if_ppp.c,v 1.149 2015/08/24 22:21:26 pooka Exp $");
106 
107 #include "ppp.h"
108 
109 #ifdef _KERNEL_OPT
110 #include "opt_inet.h"
111 #include "opt_gateway.h"
112 #include "opt_ppp.h"
113 #endif
114 
115 #ifdef INET
116 #define VJC
117 #endif
118 #define PPP_COMPRESS
119 
120 #include <sys/param.h>
121 #include <sys/proc.h>
122 #include <sys/mbuf.h>
123 #include <sys/socket.h>
124 #include <sys/ioctl.h>
125 #include <sys/kernel.h>
126 #include <sys/systm.h>
127 #include <sys/time.h>
128 #include <sys/malloc.h>
129 #include <sys/module.h>
130 #include <sys/mutex.h>
131 #include <sys/once.h>
132 #include <sys/conf.h>
133 #include <sys/kauth.h>
134 #include <sys/intr.h>
135 #include <sys/socketvar.h>
136 
137 #include <net/if.h>
138 #include <net/if_types.h>
139 #include <net/netisr.h>
140 #include <net/route.h>
141 #ifdef PPP_FILTER
142 #include <net/bpf.h>
143 #endif
144 
145 #include <netinet/in.h>
146 #include <netinet/in_systm.h>
147 #include <netinet/in_var.h>
148 #ifdef INET
149 #include <netinet/ip.h>
150 #endif
151 
152 #include <net/bpf.h>
153 
154 #include <net/slip.h>
155 
156 #ifdef VJC
157 #include <net/slcompress.h>
158 #endif
159 
160 #include <net/ppp_defs.h>
161 #include <net/if_ppp.h>
162 #include <net/if_pppvar.h>
163 #include <sys/cpu.h>
164 
165 #ifdef PPP_COMPRESS
166 #define PACKETPTR	struct mbuf *
167 #include <net/ppp-comp.h>
168 #endif
169 
170 #include "ioconf.h"
171 
172 static int	pppsioctl(struct ifnet *, u_long, void *);
173 static void	ppp_requeue(struct ppp_softc *);
174 static void	ppp_ccp(struct ppp_softc *, struct mbuf *m, int rcvd);
175 static void	ppp_ccp_closed(struct ppp_softc *);
176 static void	ppp_inproc(struct ppp_softc *, struct mbuf *);
177 static void	pppdumpm(struct mbuf *m0);
178 #ifdef ALTQ
179 static void	ppp_ifstart(struct ifnet *ifp);
180 #endif
181 
182 static void	pppintr(void *);
183 
184 /*
185  * Some useful mbuf macros not in mbuf.h.
186  */
187 #define M_IS_CLUSTER(m)	((m)->m_flags & M_EXT)
188 
189 #define M_DATASTART(m)							\
190 	(M_IS_CLUSTER(m) ? (m)->m_ext.ext_buf :				\
191 	    (m)->m_flags & M_PKTHDR ? (m)->m_pktdat : (m)->m_dat)
192 
193 #define M_DATASIZE(m)							\
194 	(M_IS_CLUSTER(m) ? (m)->m_ext.ext_size :			\
195 	    (m)->m_flags & M_PKTHDR ? MHLEN: MLEN)
196 
197 /*
198  * We define two link layer specific mbuf flags, to mark high-priority
199  * packets for output, and received packets following lost/corrupted
200  * packets.
201  */
202 #define	M_HIGHPRI	M_LINK0	/* output packet for sc_fastq */
203 #define	M_ERRMARK	M_LINK1	/* rx packet following lost/corrupted pkt */
204 
205 static int ppp_clone_create(struct if_clone *, int);
206 static int ppp_clone_destroy(struct ifnet *);
207 
208 static struct ppp_softc *ppp_create(const char *, int);
209 
210 static LIST_HEAD(, ppp_softc) ppp_softc_list;
211 static kmutex_t ppp_list_lock;
212 
213 struct if_clone ppp_cloner =
214     IF_CLONE_INITIALIZER("ppp", ppp_clone_create, ppp_clone_destroy);
215 
216 #ifdef PPP_COMPRESS
217 ONCE_DECL(ppp_compressor_mtx_init);
218 static LIST_HEAD(, compressor) ppp_compressors = { NULL };
219 static kmutex_t ppp_compressors_mtx;
220 
221 static int ppp_compressor_init(void);
222 static struct compressor *ppp_get_compressor(uint8_t);
223 static void ppp_compressor_rele(struct compressor *);
224 #endif /* PPP_COMPRESS */
225 
226 
227 /*
228  * Called from boot code to establish ppp interfaces.
229  */
230 void
231 pppattach(int n __unused)
232 {
233 	extern struct linesw ppp_disc;
234 
235 	if (ttyldisc_attach(&ppp_disc) != 0)
236 		panic("pppattach");
237 
238 	mutex_init(&ppp_list_lock, MUTEX_DEFAULT, IPL_NONE);
239 	LIST_INIT(&ppp_softc_list);
240 	if_clone_attach(&ppp_cloner);
241 	RUN_ONCE(&ppp_compressor_mtx_init, ppp_compressor_init);
242 }
243 
244 static struct ppp_softc *
245 ppp_create(const char *name, int unit)
246 {
247 	struct ppp_softc *sc, *sci, *scl = NULL;
248 
249 	sc = malloc(sizeof(*sc), M_DEVBUF, M_WAIT|M_ZERO);
250 
251 	mutex_enter(&ppp_list_lock);
252 	if (unit == -1) {
253 		int i = 0;
254 		LIST_FOREACH(sci, &ppp_softc_list, sc_iflist) {
255 			scl = sci;
256 			if (i < sci->sc_unit) {
257 				unit = i;
258 				break;
259 			} else {
260 #ifdef DIAGNOSTIC
261 				KASSERT(i == sci->sc_unit);
262 #endif
263 				i++;
264 			}
265 		}
266 		if (unit == -1)
267 			unit = i;
268 	} else {
269 		LIST_FOREACH(sci, &ppp_softc_list, sc_iflist) {
270 			scl = sci;
271 			if (unit < sci->sc_unit)
272 				break;
273 			else if (unit == sci->sc_unit) {
274 				free(sc, M_DEVBUF);
275 				return NULL;
276 			}
277 		}
278 	}
279 
280 	if (sci != NULL)
281 		LIST_INSERT_BEFORE(sci, sc, sc_iflist);
282 	else if (scl != NULL)
283 		LIST_INSERT_AFTER(scl, sc, sc_iflist);
284 	else
285 		LIST_INSERT_HEAD(&ppp_softc_list, sc, sc_iflist);
286 
287 	mutex_exit(&ppp_list_lock);
288 
289 	if_initname(&sc->sc_if, name, sc->sc_unit = unit);
290 	callout_init(&sc->sc_timo_ch, 0);
291 	sc->sc_if.if_softc = sc;
292 	sc->sc_if.if_mtu = PPP_MTU;
293 	sc->sc_if.if_flags = IFF_POINTOPOINT | IFF_MULTICAST;
294 	sc->sc_if.if_type = IFT_PPP;
295 	sc->sc_if.if_hdrlen = PPP_HDRLEN;
296 	sc->sc_if.if_dlt = DLT_NULL;
297 	sc->sc_if.if_ioctl = pppsioctl;
298 	sc->sc_if.if_output = pppoutput;
299 #ifdef ALTQ
300 	sc->sc_if.if_start = ppp_ifstart;
301 #endif
302 	IFQ_SET_MAXLEN(&sc->sc_if.if_snd, IFQ_MAXLEN);
303 	sc->sc_inq.ifq_maxlen = IFQ_MAXLEN;
304 	sc->sc_fastq.ifq_maxlen = IFQ_MAXLEN;
305 	sc->sc_rawq.ifq_maxlen = IFQ_MAXLEN;
306 	/* Ratio of 1:2 packets between the regular and the fast queue */
307 	sc->sc_maxfastq = 2;
308 	IFQ_SET_READY(&sc->sc_if.if_snd);
309 	if_attach(&sc->sc_if);
310 	if_alloc_sadl(&sc->sc_if);
311 	bpf_attach(&sc->sc_if, DLT_NULL, 0);
312 	return sc;
313 }
314 
315 static int
316 ppp_clone_create(struct if_clone *ifc, int unit)
317 {
318 	return ppp_create(ifc->ifc_name, unit) == NULL ? EEXIST : 0;
319 }
320 
321 static int
322 ppp_clone_destroy(struct ifnet *ifp)
323 {
324 	struct ppp_softc *sc = (struct ppp_softc *)ifp->if_softc;
325 
326 	if (sc->sc_devp != NULL)
327 		return EBUSY; /* Not removing it */
328 
329 	mutex_enter(&ppp_list_lock);
330 	LIST_REMOVE(sc, sc_iflist);
331 	mutex_exit(&ppp_list_lock);
332 
333 	bpf_detach(ifp);
334 	if_detach(ifp);
335 
336 	free(sc, M_DEVBUF);
337 	return 0;
338 }
339 
340 /*
341  * Allocate a ppp interface unit and initialize it.
342  */
343 struct ppp_softc *
344 pppalloc(pid_t pid)
345 {
346 	struct ppp_softc *sc = NULL, *scf;
347 	int i;
348 
349 	mutex_enter(&ppp_list_lock);
350 	LIST_FOREACH(scf, &ppp_softc_list, sc_iflist) {
351 		if (scf->sc_xfer == pid) {
352 			scf->sc_xfer = 0;
353 			mutex_exit(&ppp_list_lock);
354 			return scf;
355 		}
356 		if (scf->sc_devp == NULL && sc == NULL)
357 			sc = scf;
358 	}
359 	mutex_exit(&ppp_list_lock);
360 
361 	if (sc == NULL)
362 		sc = ppp_create(ppp_cloner.ifc_name, -1);
363 
364 	sc->sc_si = softint_establish(SOFTINT_NET, pppintr, sc);
365 	if (sc->sc_si == NULL) {
366 		printf("%s: unable to establish softintr\n",
367 		    sc->sc_if.if_xname);
368 		return (NULL);
369 	}
370 	sc->sc_flags = 0;
371 	sc->sc_mru = PPP_MRU;
372 	sc->sc_relinq = NULL;
373 	(void)memset(&sc->sc_stats, 0, sizeof(sc->sc_stats));
374 #ifdef VJC
375 	sc->sc_comp = malloc(sizeof(struct slcompress), M_DEVBUF, M_NOWAIT);
376 	if (sc->sc_comp)
377 		sl_compress_init(sc->sc_comp);
378 #endif
379 #ifdef PPP_COMPRESS
380 	sc->sc_xc_state = NULL;
381 	sc->sc_rc_state = NULL;
382 #endif /* PPP_COMPRESS */
383 	for (i = 0; i < NUM_NP; ++i)
384 		sc->sc_npmode[i] = NPMODE_ERROR;
385 	sc->sc_npqueue = NULL;
386 	sc->sc_npqtail = &sc->sc_npqueue;
387 	sc->sc_last_sent = sc->sc_last_recv = time_second;
388 
389 	return sc;
390 }
391 
392 /*
393  * Deallocate a ppp unit.  Must be called at splsoftnet or higher.
394  */
395 void
396 pppdealloc(struct ppp_softc *sc)
397 {
398 	struct mbuf *m;
399 
400 	softint_disestablish(sc->sc_si);
401 	if_down(&sc->sc_if);
402 	sc->sc_if.if_flags &= ~(IFF_UP|IFF_RUNNING);
403 	sc->sc_devp = NULL;
404 	sc->sc_xfer = 0;
405 	for (;;) {
406 		IF_DEQUEUE(&sc->sc_rawq, m);
407 		if (m == NULL)
408 			break;
409 		m_freem(m);
410 	}
411 	for (;;) {
412 		IF_DEQUEUE(&sc->sc_inq, m);
413 		if (m == NULL)
414 			break;
415 		m_freem(m);
416 	}
417 	for (;;) {
418 		IF_DEQUEUE(&sc->sc_fastq, m);
419 		if (m == NULL)
420 			break;
421 		m_freem(m);
422 	}
423 	while ((m = sc->sc_npqueue) != NULL) {
424 		sc->sc_npqueue = m->m_nextpkt;
425 		m_freem(m);
426 	}
427 	if (sc->sc_togo != NULL) {
428 		m_freem(sc->sc_togo);
429 		sc->sc_togo = NULL;
430 	}
431 #ifdef PPP_COMPRESS
432 	ppp_ccp_closed(sc);
433 	sc->sc_xc_state = NULL;
434 	sc->sc_rc_state = NULL;
435 #endif /* PPP_COMPRESS */
436 #ifdef PPP_FILTER
437 	if (sc->sc_pass_filt_in.bf_insns != 0) {
438 		free(sc->sc_pass_filt_in.bf_insns, M_DEVBUF);
439 		sc->sc_pass_filt_in.bf_insns = 0;
440 		sc->sc_pass_filt_in.bf_len = 0;
441 	}
442 	if (sc->sc_pass_filt_out.bf_insns != 0) {
443 		free(sc->sc_pass_filt_out.bf_insns, M_DEVBUF);
444 		sc->sc_pass_filt_out.bf_insns = 0;
445 		sc->sc_pass_filt_out.bf_len = 0;
446 	}
447 	if (sc->sc_active_filt_in.bf_insns != 0) {
448 		free(sc->sc_active_filt_in.bf_insns, M_DEVBUF);
449 		sc->sc_active_filt_in.bf_insns = 0;
450 		sc->sc_active_filt_in.bf_len = 0;
451 	}
452 	if (sc->sc_active_filt_out.bf_insns != 0) {
453 		free(sc->sc_active_filt_out.bf_insns, M_DEVBUF);
454 		sc->sc_active_filt_out.bf_insns = 0;
455 		sc->sc_active_filt_out.bf_len = 0;
456 	}
457 #endif /* PPP_FILTER */
458 #ifdef VJC
459 	if (sc->sc_comp != 0) {
460 		free(sc->sc_comp, M_DEVBUF);
461 		sc->sc_comp = 0;
462 	}
463 #endif
464 	(void)ppp_clone_destroy(&sc->sc_if);
465 }
466 
467 /*
468  * Ioctl routine for generic ppp devices.
469  */
470 int
471 pppioctl(struct ppp_softc *sc, u_long cmd, void *data, int flag,
472     struct lwp *l)
473 {
474 	int s, error, flags, mru, npx;
475 	u_int nb;
476 	struct ppp_option_data *odp;
477 	struct compressor *cp;
478 	struct npioctl *npi;
479 	time_t t;
480 #ifdef PPP_FILTER
481 	struct bpf_program *bp, *nbp;
482 	struct bpf_insn *newcode, *oldcode;
483 	int newcodelen;
484 #endif /* PPP_FILTER */
485 #ifdef	PPP_COMPRESS
486 	u_char ccp_option[CCP_MAX_OPTION_LENGTH];
487 #endif
488 
489 	switch (cmd) {
490 	case PPPIOCSFLAGS:
491 	case PPPIOCSMRU:
492 	case PPPIOCSMAXCID:
493 	case PPPIOCSCOMPRESS:
494 	case PPPIOCSNPMODE:
495 		if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE,
496 			KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, &sc->sc_if,
497 			KAUTH_ARG(cmd), NULL) != 0)
498 			return (EPERM);
499 		break;
500 	case PPPIOCXFERUNIT:
501 		/* XXX: Why is this privileged?! */
502 		if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE,
503 			KAUTH_REQ_NETWORK_INTERFACE_GETPRIV, &sc->sc_if,
504 			KAUTH_ARG(cmd), NULL) != 0)
505 			return (EPERM);
506 		break;
507 	default:
508 		break;
509 	}
510 
511 	switch (cmd) {
512 	case FIONREAD:
513 		*(int *)data = sc->sc_inq.ifq_len;
514 		break;
515 
516 	case PPPIOCGUNIT:
517 		*(int *)data = sc->sc_unit;
518 		break;
519 
520 	case PPPIOCGFLAGS:
521 		*(u_int *)data = sc->sc_flags;
522 		break;
523 
524 	case PPPIOCGRAWIN:
525 	{
526 		struct ppp_rawin *rwin = (struct ppp_rawin *)data;
527 		u_char c, q = 0;
528 
529 		for (c = sc->sc_rawin_start; c < sizeof(sc->sc_rawin.buf);)
530 			rwin->buf[q++] = sc->sc_rawin.buf[c++];
531 
532 		for (c = 0; c < sc->sc_rawin_start;)
533 			rwin->buf[q++] = sc->sc_rawin.buf[c++];
534 
535 		rwin->count = sc->sc_rawin.count;
536 	}
537 	break;
538 
539 	case PPPIOCSFLAGS:
540 		flags = *(int *)data & SC_MASK;
541 		s = splsoftnet();
542 #ifdef PPP_COMPRESS
543 		if (sc->sc_flags & SC_CCP_OPEN && !(flags & SC_CCP_OPEN))
544 			ppp_ccp_closed(sc);
545 #endif
546 		splhigh();	/* XXX IMP ME HARDER */
547 		sc->sc_flags = (sc->sc_flags & ~SC_MASK) | flags;
548 		splx(s);
549 		break;
550 
551 	case PPPIOCSMRU:
552 		mru = *(int *)data;
553 		if (mru >= PPP_MINMRU && mru <= PPP_MAXMRU)
554 			sc->sc_mru = mru;
555 		break;
556 
557 	case PPPIOCGMRU:
558 		*(int *)data = sc->sc_mru;
559 		break;
560 
561 #ifdef VJC
562 	case PPPIOCSMAXCID:
563 		if (sc->sc_comp) {
564 			s = splsoftnet();
565 			sl_compress_setup(sc->sc_comp, *(int *)data);
566 			splx(s);
567 		}
568 		break;
569 #endif
570 
571 	case PPPIOCXFERUNIT:
572 		sc->sc_xfer = l->l_proc->p_pid;
573 		break;
574 
575 #ifdef PPP_COMPRESS
576 	case PPPIOCSCOMPRESS:
577 		odp = (struct ppp_option_data *) data;
578 		nb = odp->length;
579 		if (nb > sizeof(ccp_option))
580 			nb = sizeof(ccp_option);
581 		if ((error = copyin(odp->ptr, ccp_option, nb)) != 0)
582 			return (error);
583 		/* preliminary check on the length byte */
584 		if (ccp_option[1] < 2)
585 			return (EINVAL);
586 		cp = ppp_get_compressor(ccp_option[0]);
587 		if (cp == NULL) {
588 			if (sc->sc_flags & SC_DEBUG)
589 				printf("%s: no compressor for [%x %x %x], %x\n",
590 				    sc->sc_if.if_xname, ccp_option[0],
591 				    ccp_option[1], ccp_option[2], nb);
592 			return (EINVAL);	/* no handler found */
593 		}
594 		/*
595 		 * Found a handler for the protocol - try to allocate
596 		 * a compressor or decompressor.
597 		 */
598 		error = 0;
599 		if (odp->transmit) {
600 			s = splsoftnet();
601 			if (sc->sc_xc_state != NULL) {
602 				(*sc->sc_xcomp->comp_free)(sc->sc_xc_state);
603 				ppp_compressor_rele(sc->sc_xcomp);
604 			}
605 			sc->sc_xcomp = cp;
606 			sc->sc_xc_state = cp->comp_alloc(ccp_option, nb);
607 			if (sc->sc_xc_state == NULL) {
608 				if (sc->sc_flags & SC_DEBUG)
609 					printf("%s: comp_alloc failed\n",
610 					    sc->sc_if.if_xname);
611 				error = ENOBUFS;
612 			}
613 			splhigh();	/* XXX IMP ME HARDER */
614 			sc->sc_flags &= ~SC_COMP_RUN;
615 			splx(s);
616 		} else {
617 			s = splsoftnet();
618 			if (sc->sc_rc_state != NULL) {
619 				(*sc->sc_rcomp->decomp_free)(sc->sc_rc_state);
620 				ppp_compressor_rele(sc->sc_rcomp);
621 			}
622 			sc->sc_rcomp = cp;
623 			sc->sc_rc_state = cp->decomp_alloc(ccp_option, nb);
624 			if (sc->sc_rc_state == NULL) {
625 				if (sc->sc_flags & SC_DEBUG)
626 					printf("%s: decomp_alloc failed\n",
627 					    sc->sc_if.if_xname);
628 				error = ENOBUFS;
629 			}
630 			splhigh();	/* XXX IMP ME HARDER */
631 			sc->sc_flags &= ~SC_DECOMP_RUN;
632 			splx(s);
633 		}
634 		return (error);
635 #endif /* PPP_COMPRESS */
636 
637 	case PPPIOCGNPMODE:
638 	case PPPIOCSNPMODE:
639 		npi = (struct npioctl *) data;
640 		switch (npi->protocol) {
641 		case PPP_IP:
642 			npx = NP_IP;
643 			break;
644 		case PPP_IPV6:
645 			npx = NP_IPV6;
646 			break;
647 		default:
648 			return EINVAL;
649 		}
650 		if (cmd == PPPIOCGNPMODE) {
651 			npi->mode = sc->sc_npmode[npx];
652 		} else {
653 			if (npi->mode != sc->sc_npmode[npx]) {
654 				s = splnet();
655 				sc->sc_npmode[npx] = npi->mode;
656 				if (npi->mode != NPMODE_QUEUE) {
657 					ppp_requeue(sc);
658 					ppp_restart(sc);
659 				}
660 				splx(s);
661 			}
662 		}
663 		break;
664 
665 	case PPPIOCGIDLE:
666 		s = splsoftnet();
667 		t = time_second;
668 		((struct ppp_idle *)data)->xmit_idle = t - sc->sc_last_sent;
669 		((struct ppp_idle *)data)->recv_idle = t - sc->sc_last_recv;
670 		splx(s);
671 		break;
672 
673 #ifdef PPP_FILTER
674 	case PPPIOCSPASS:
675 	case PPPIOCSACTIVE:
676 		/* These are no longer supported. */
677 		return EOPNOTSUPP;
678 
679 	case PPPIOCSIPASS:
680 	case PPPIOCSOPASS:
681 	case PPPIOCSIACTIVE:
682 	case PPPIOCSOACTIVE:
683 		nbp = (struct bpf_program *) data;
684 		if ((unsigned) nbp->bf_len > BPF_MAXINSNS)
685 			return EINVAL;
686 		newcodelen = nbp->bf_len * sizeof(struct bpf_insn);
687 		if (newcodelen != 0) {
688 			newcode = malloc(newcodelen, M_DEVBUF, M_WAITOK);
689 			/* WAITOK -- malloc() never fails. */
690 			if ((error = copyin((void *)nbp->bf_insns,
691 				    (void *)newcode, newcodelen)) != 0) {
692 				free(newcode, M_DEVBUF);
693 				return error;
694 			}
695 			if (!bpf_validate(newcode, nbp->bf_len)) {
696 				free(newcode, M_DEVBUF);
697 				return EINVAL;
698 			}
699 		} else
700 			newcode = 0;
701 		switch (cmd) {
702 		case PPPIOCSIPASS:
703 			bp = &sc->sc_pass_filt_in;
704 			break;
705 
706 		case PPPIOCSOPASS:
707 			bp = &sc->sc_pass_filt_out;
708 			break;
709 
710 		case PPPIOCSIACTIVE:
711 			bp = &sc->sc_active_filt_in;
712 			break;
713 
714 		case PPPIOCSOACTIVE:
715 			bp = &sc->sc_active_filt_out;
716 			break;
717 		default:
718 			free(newcode, M_DEVBUF);
719 			return (EPASSTHROUGH);
720 		}
721 		oldcode = bp->bf_insns;
722 		s = splnet();
723 		bp->bf_len = nbp->bf_len;
724 		bp->bf_insns = newcode;
725 		splx(s);
726 		if (oldcode != 0)
727 			free(oldcode, M_DEVBUF);
728 		break;
729 #endif /* PPP_FILTER */
730 
731 	default:
732 		return (EPASSTHROUGH);
733 	}
734 	return (0);
735 }
736 
737 /*
738  * Process an ioctl request to the ppp network interface.
739  */
740 static int
741 pppsioctl(struct ifnet *ifp, u_long cmd, void *data)
742 {
743 	struct ppp_softc *sc = ifp->if_softc;
744 	struct ifaddr *ifa = (struct ifaddr *)data;
745 	struct ifreq *ifr = (struct ifreq *)data;
746 	struct ppp_stats *psp;
747 #ifdef	PPP_COMPRESS
748 	struct ppp_comp_stats *pcp;
749 #endif
750 	int s = splnet(), error = 0;
751 
752 	switch (cmd) {
753 	case SIOCSIFFLAGS:
754 		if ((error = ifioctl_common(ifp, cmd, data)) != 0)
755 			break;
756 		if ((ifp->if_flags & IFF_RUNNING) == 0)
757 			ifp->if_flags &= ~IFF_UP;
758 		break;
759 
760 	case SIOCINITIFADDR:
761 		switch (ifa->ifa_addr->sa_family) {
762 #ifdef INET
763 		case AF_INET:
764 			break;
765 #endif
766 #ifdef INET6
767 		case AF_INET6:
768 			break;
769 #endif
770 		default:
771 			error = EAFNOSUPPORT;
772 			break;
773 		}
774 		ifa->ifa_rtrequest = p2p_rtrequest;
775 		break;
776 
777 	case SIOCADDMULTI:
778 	case SIOCDELMULTI:
779 		if (ifr == NULL) {
780 			error = EAFNOSUPPORT;
781 			break;
782 		}
783 		switch (ifreq_getaddr(cmd, ifr)->sa_family) {
784 #ifdef INET
785 		case AF_INET:
786 			break;
787 #endif
788 #ifdef INET6
789 		case AF_INET6:
790 			break;
791 #endif
792 		default:
793 			error = EAFNOSUPPORT;
794 			break;
795 		}
796 		break;
797 
798 	case SIOCGPPPSTATS:
799 		psp = &((struct ifpppstatsreq *) data)->stats;
800 		memset(psp, 0, sizeof(*psp));
801 		psp->p = sc->sc_stats;
802 #if defined(VJC) && !defined(SL_NO_STATS)
803 		if (sc->sc_comp) {
804 			psp->vj.vjs_packets = sc->sc_comp->sls_packets;
805 			psp->vj.vjs_compressed = sc->sc_comp->sls_compressed;
806 			psp->vj.vjs_searches = sc->sc_comp->sls_searches;
807 			psp->vj.vjs_misses = sc->sc_comp->sls_misses;
808 			psp->vj.vjs_uncompressedin = sc->sc_comp->sls_uncompressedin;
809 			psp->vj.vjs_compressedin = sc->sc_comp->sls_compressedin;
810 			psp->vj.vjs_errorin = sc->sc_comp->sls_errorin;
811 			psp->vj.vjs_tossed = sc->sc_comp->sls_tossed;
812 		}
813 #endif /* VJC */
814 		break;
815 
816 #ifdef PPP_COMPRESS
817 	case SIOCGPPPCSTATS:
818 		pcp = &((struct ifpppcstatsreq *) data)->stats;
819 		memset(pcp, 0, sizeof(*pcp));
820 		if (sc->sc_xc_state != NULL)
821 			(*sc->sc_xcomp->comp_stat)(sc->sc_xc_state, &pcp->c);
822 		if (sc->sc_rc_state != NULL)
823 			(*sc->sc_rcomp->decomp_stat)(sc->sc_rc_state, &pcp->d);
824 		break;
825 #endif /* PPP_COMPRESS */
826 
827 	default:
828 		if ((error = ifioctl_common(&sc->sc_if, cmd, data)) == ENETRESET)
829 			error = 0;
830 		break;
831 	}
832 	splx(s);
833 	return (error);
834 }
835 
836 /*
837  * Queue a packet.  Start transmission if not active.
838  * Packet is placed in Information field of PPP frame.
839  */
840 int
841 pppoutput(struct ifnet *ifp, struct mbuf *m0, const struct sockaddr *dst,
842     struct rtentry *rtp)
843 {
844 	struct ppp_softc *sc = ifp->if_softc;
845 	int protocol, address, control;
846 	u_char *cp;
847 	int s, error;
848 #ifdef INET
849 	struct ip *ip;
850 #endif
851 	struct ifqueue *ifq;
852 	enum NPmode mode;
853 	int len;
854 	ALTQ_DECL(struct altq_pktattr pktattr;)
855 
856 	    if (sc->sc_devp == NULL || (ifp->if_flags & IFF_RUNNING) == 0
857 		|| ((ifp->if_flags & IFF_UP) == 0 && dst->sa_family != AF_UNSPEC)) {
858 		    error = ENETDOWN;	/* sort of */
859 		    goto bad;
860 	    }
861 
862 	IFQ_CLASSIFY(&ifp->if_snd, m0, dst->sa_family, &pktattr);
863 
864 	/*
865 	 * Compute PPP header.
866 	 */
867 	m0->m_flags &= ~M_HIGHPRI;
868 	switch (dst->sa_family) {
869 #ifdef INET
870 	case AF_INET:
871 		address = PPP_ALLSTATIONS;
872 		control = PPP_UI;
873 		protocol = PPP_IP;
874 		mode = sc->sc_npmode[NP_IP];
875 
876 		/*
877 		 * If this packet has the "low delay" bit set in the IP header,
878 		 * put it on the fastq instead.
879 		 */
880 		ip = mtod(m0, struct ip *);
881 		if (ip->ip_tos & IPTOS_LOWDELAY)
882 			m0->m_flags |= M_HIGHPRI;
883 		break;
884 #endif
885 #ifdef INET6
886 	case AF_INET6:
887 		address = PPP_ALLSTATIONS;	/*XXX*/
888 		control = PPP_UI;		/*XXX*/
889 		protocol = PPP_IPV6;
890 		mode = sc->sc_npmode[NP_IPV6];
891 
892 #if 0	/* XXX flowinfo/traffic class, maybe? */
893 	/*
894 	 * If this packet has the "low delay" bit set in the IP header,
895 	 * put it on the fastq instead.
896 	 */
897 		ip = mtod(m0, struct ip *);
898 		if (ip->ip_tos & IPTOS_LOWDELAY)
899 			m0->m_flags |= M_HIGHPRI;
900 #endif
901 		break;
902 #endif
903 	case AF_UNSPEC:
904 		address = PPP_ADDRESS(dst->sa_data);
905 		control = PPP_CONTROL(dst->sa_data);
906 		protocol = PPP_PROTOCOL(dst->sa_data);
907 		mode = NPMODE_PASS;
908 		break;
909 	default:
910 		printf("%s: af%d not supported\n", ifp->if_xname,
911 		    dst->sa_family);
912 		error = EAFNOSUPPORT;
913 		goto bad;
914 	}
915 
916 	/*
917 	 * Drop this packet, or return an error, if necessary.
918 	 */
919 	if (mode == NPMODE_ERROR) {
920 		error = ENETDOWN;
921 		goto bad;
922 	}
923 	if (mode == NPMODE_DROP) {
924 		error = 0;
925 		goto bad;
926 	}
927 
928 	/*
929 	 * Add PPP header.
930 	 */
931 	M_PREPEND(m0, PPP_HDRLEN, M_DONTWAIT);
932 	if (m0 == NULL) {
933 		error = ENOBUFS;
934 		goto bad;
935 	}
936 
937 	cp = mtod(m0, u_char *);
938 	*cp++ = address;
939 	*cp++ = control;
940 	*cp++ = protocol >> 8;
941 	*cp++ = protocol & 0xff;
942 
943 	len = m_length(m0);
944 
945 	if (sc->sc_flags & SC_LOG_OUTPKT) {
946 		printf("%s output: ", ifp->if_xname);
947 		pppdumpm(m0);
948 	}
949 
950 	if ((protocol & 0x8000) == 0) {
951 #ifdef PPP_FILTER
952 		/*
953 		 * Apply the pass and active filters to the packet,
954 		 * but only if it is a data packet.
955 		 */
956 		if (sc->sc_pass_filt_out.bf_insns != 0
957 		    && bpf_filter(sc->sc_pass_filt_out.bf_insns,
958 			(u_char *)m0, len, 0) == 0) {
959 			error = 0;		/* drop this packet */
960 			goto bad;
961 		}
962 
963 		/*
964 		 * Update the time we sent the most recent packet.
965 		 */
966 		if (sc->sc_active_filt_out.bf_insns == 0
967 		    || bpf_filter(sc->sc_active_filt_out.bf_insns,
968 			(u_char *)m0, len, 0))
969 			sc->sc_last_sent = time_second;
970 #else
971 		/*
972 		 * Update the time we sent the most recent packet.
973 		 */
974 		sc->sc_last_sent = time_second;
975 #endif /* PPP_FILTER */
976 	}
977 
978 	/*
979 	 * See if bpf wants to look at the packet.
980 	 */
981 	bpf_mtap(&sc->sc_if, m0);
982 
983 	/*
984 	 * Put the packet on the appropriate queue.
985 	 */
986 	s = splnet();
987 	if (mode == NPMODE_QUEUE) {
988 		/* XXX we should limit the number of packets on this queue */
989 		*sc->sc_npqtail = m0;
990 		m0->m_nextpkt = NULL;
991 		sc->sc_npqtail = &m0->m_nextpkt;
992 	} else {
993 		ifq = (m0->m_flags & M_HIGHPRI) ? &sc->sc_fastq : NULL;
994 		if ((error = ifq_enqueue2(&sc->sc_if, ifq, m0
995 			    ALTQ_COMMA ALTQ_DECL(&pktattr))) != 0) {
996 			splx(s);
997 			sc->sc_if.if_oerrors++;
998 			sc->sc_stats.ppp_oerrors++;
999 			return (error);
1000 		}
1001 		ppp_restart(sc);
1002 	}
1003 	ifp->if_opackets++;
1004 	ifp->if_obytes += len;
1005 
1006 	splx(s);
1007 	return (0);
1008 
1009 bad:
1010 	m_freem(m0);
1011 	return (error);
1012 }
1013 
1014 /*
1015  * After a change in the NPmode for some NP, move packets from the
1016  * npqueue to the send queue or the fast queue as appropriate.
1017  * Should be called at splnet, since we muck with the queues.
1018  */
1019 static void
1020 ppp_requeue(struct ppp_softc *sc)
1021 {
1022 	struct mbuf *m, **mpp;
1023 	struct ifqueue *ifq;
1024 	enum NPmode mode;
1025 	int error;
1026 
1027 	for (mpp = &sc->sc_npqueue; (m = *mpp) != NULL; ) {
1028 		switch (PPP_PROTOCOL(mtod(m, u_char *))) {
1029 		case PPP_IP:
1030 			mode = sc->sc_npmode[NP_IP];
1031 			break;
1032 		case PPP_IPV6:
1033 			mode = sc->sc_npmode[NP_IPV6];
1034 			break;
1035 		default:
1036 			mode = NPMODE_PASS;
1037 		}
1038 
1039 		switch (mode) {
1040 		case NPMODE_PASS:
1041 			/*
1042 			 * This packet can now go on one of the queues to
1043 			 * be sent.
1044 			 */
1045 			*mpp = m->m_nextpkt;
1046 			m->m_nextpkt = NULL;
1047 			ifq = (m->m_flags & M_HIGHPRI) ? &sc->sc_fastq : NULL;
1048 			if ((error = ifq_enqueue2(&sc->sc_if, ifq, m ALTQ_COMMA
1049 				    ALTQ_DECL(NULL))) != 0) {
1050 				sc->sc_if.if_oerrors++;
1051 				sc->sc_stats.ppp_oerrors++;
1052 			}
1053 			break;
1054 
1055 		case NPMODE_DROP:
1056 		case NPMODE_ERROR:
1057 			*mpp = m->m_nextpkt;
1058 			m_freem(m);
1059 			break;
1060 
1061 		case NPMODE_QUEUE:
1062 			mpp = &m->m_nextpkt;
1063 			break;
1064 		}
1065 	}
1066 	sc->sc_npqtail = mpp;
1067 }
1068 
1069 /*
1070  * Transmitter has finished outputting some stuff;
1071  * remember to call sc->sc_start later at splsoftnet.
1072  */
1073 void
1074 ppp_restart(struct ppp_softc *sc)
1075 {
1076 	int s = splhigh();	/* XXX IMP ME HARDER */
1077 
1078 	sc->sc_flags &= ~SC_TBUSY;
1079 	softint_schedule(sc->sc_si);
1080 	splx(s);
1081 }
1082 
1083 /*
1084  * Get a packet to send.  This procedure is intended to be called at
1085  * splsoftnet, since it may involve time-consuming operations such as
1086  * applying VJ compression, packet compression, address/control and/or
1087  * protocol field compression to the packet.
1088  */
1089 struct mbuf *
1090 ppp_dequeue(struct ppp_softc *sc)
1091 {
1092 	struct mbuf *m, *mp;
1093 	u_char *cp;
1094 	int address, control, protocol;
1095 	int s;
1096 
1097 	/*
1098 	 * Grab a packet to send: first try the fast queue, then the
1099 	 * normal queue.
1100 	 */
1101 	s = splnet();
1102 	if (sc->sc_nfastq < sc->sc_maxfastq) {
1103 		IF_DEQUEUE(&sc->sc_fastq, m);
1104 		if (m != NULL)
1105 			sc->sc_nfastq++;
1106 		else
1107 			IFQ_DEQUEUE(&sc->sc_if.if_snd, m);
1108 	} else {
1109 		sc->sc_nfastq = 0;
1110 		IFQ_DEQUEUE(&sc->sc_if.if_snd, m);
1111 		if (m == NULL) {
1112 			IF_DEQUEUE(&sc->sc_fastq, m);
1113 			if (m != NULL)
1114 				sc->sc_nfastq++;
1115 		}
1116 	}
1117 	splx(s);
1118 
1119 	if (m == NULL)
1120 		return NULL;
1121 
1122 	++sc->sc_stats.ppp_opackets;
1123 
1124 	/*
1125 	 * Extract the ppp header of the new packet.
1126 	 * The ppp header will be in one mbuf.
1127 	 */
1128 	cp = mtod(m, u_char *);
1129 	address = PPP_ADDRESS(cp);
1130 	control = PPP_CONTROL(cp);
1131 	protocol = PPP_PROTOCOL(cp);
1132 
1133 	switch (protocol) {
1134 	case PPP_IP:
1135 #ifdef VJC
1136 		/*
1137 		 * If the packet is a TCP/IP packet, see if we can compress it.
1138 		 */
1139 		if ((sc->sc_flags & SC_COMP_TCP) && sc->sc_comp != NULL) {
1140 			struct ip *ip;
1141 			int type;
1142 
1143 			mp = m;
1144 			ip = (struct ip *) (cp + PPP_HDRLEN);
1145 			if (mp->m_len <= PPP_HDRLEN) {
1146 				mp = mp->m_next;
1147 				if (mp == NULL)
1148 					break;
1149 				ip = mtod(mp, struct ip *);
1150 			}
1151 			/*
1152 			 * This code assumes the IP/TCP header is in one
1153 			 * non-shared mbuf
1154 			 */
1155 			if (ip->ip_p == IPPROTO_TCP) {
1156 				type = sl_compress_tcp(mp, ip, sc->sc_comp,
1157 				    !(sc->sc_flags & SC_NO_TCP_CCID));
1158 				switch (type) {
1159 				case TYPE_UNCOMPRESSED_TCP:
1160 					protocol = PPP_VJC_UNCOMP;
1161 					break;
1162 				case TYPE_COMPRESSED_TCP:
1163 					protocol = PPP_VJC_COMP;
1164 					cp = mtod(m, u_char *);
1165 					cp[0] = address; /* Header has moved */
1166 					cp[1] = control;
1167 					cp[2] = 0;
1168 					break;
1169 				}
1170 				/* Update protocol in PPP header */
1171 				cp[3] = protocol;
1172 			}
1173 		}
1174 #endif	/* VJC */
1175 		break;
1176 
1177 #ifdef PPP_COMPRESS
1178 	case PPP_CCP:
1179 		ppp_ccp(sc, m, 0);
1180 		break;
1181 #endif	/* PPP_COMPRESS */
1182 	}
1183 
1184 #ifdef PPP_COMPRESS
1185 	if (protocol != PPP_LCP && protocol != PPP_CCP
1186 	    && sc->sc_xc_state && (sc->sc_flags & SC_COMP_RUN)) {
1187 		struct mbuf *mcomp = NULL;
1188 		int slen;
1189 
1190 		slen = 0;
1191 		for (mp = m; mp != NULL; mp = mp->m_next)
1192 			slen += mp->m_len;
1193 		(*sc->sc_xcomp->compress)
1194 		    (sc->sc_xc_state, &mcomp, m, slen, sc->sc_if.if_mtu + PPP_HDRLEN);
1195 		if (mcomp != NULL) {
1196 			if (sc->sc_flags & SC_CCP_UP) {
1197 				/*
1198 				 * Send the compressed packet instead of the
1199 				 * original.
1200 				 */
1201 				m_freem(m);
1202 				m = mcomp;
1203 				cp = mtod(m, u_char *);
1204 				protocol = cp[3];
1205 			} else {
1206 				/*
1207 				 * Can't transmit compressed packets until CCP
1208 				 * is up.
1209 				 */
1210 				m_freem(mcomp);
1211 			}
1212 		}
1213 	}
1214 #endif	/* PPP_COMPRESS */
1215 
1216 	/*
1217 	 * Compress the address/control and protocol, if possible.
1218 	 */
1219 	if (sc->sc_flags & SC_COMP_AC && address == PPP_ALLSTATIONS &&
1220 	    control == PPP_UI && protocol != PPP_ALLSTATIONS &&
1221 	    protocol != PPP_LCP) {
1222 		/* can compress address/control */
1223 		m->m_data += 2;
1224 		m->m_len -= 2;
1225 	}
1226 	if (sc->sc_flags & SC_COMP_PROT && protocol < 0xFF) {
1227 		/* can compress protocol */
1228 		if (mtod(m, u_char *) == cp) {
1229 			cp[2] = cp[1];	/* move address/control up */
1230 			cp[1] = cp[0];
1231 		}
1232 		++m->m_data;
1233 		--m->m_len;
1234 	}
1235 
1236 	return m;
1237 }
1238 
1239 /*
1240  * Software interrupt routine, called at splsoftnet.
1241  */
1242 static void
1243 pppintr(void *arg)
1244 {
1245 	struct ppp_softc *sc = arg;
1246 	struct mbuf *m;
1247 	int s;
1248 
1249 	mutex_enter(softnet_lock);
1250 	if (!(sc->sc_flags & SC_TBUSY)
1251 	    && (IFQ_IS_EMPTY(&sc->sc_if.if_snd) == 0 || sc->sc_fastq.ifq_head
1252 		|| sc->sc_outm)) {
1253 		s = splhigh();	/* XXX IMP ME HARDER */
1254 		sc->sc_flags |= SC_TBUSY;
1255 		splx(s);
1256 		(*sc->sc_start)(sc);
1257 	}
1258 	for (;;) {
1259 		s = splnet();
1260 		IF_DEQUEUE(&sc->sc_rawq, m);
1261 		splx(s);
1262 		if (m == NULL)
1263 			break;
1264 		ppp_inproc(sc, m);
1265 	}
1266 	mutex_exit(softnet_lock);
1267 }
1268 
1269 #ifdef PPP_COMPRESS
1270 /*
1271  * Handle a CCP packet.	 `rcvd' is 1 if the packet was received,
1272  * 0 if it is about to be transmitted.
1273  */
1274 static void
1275 ppp_ccp(struct ppp_softc *sc, struct mbuf *m, int rcvd)
1276 {
1277 	u_char *dp, *ep;
1278 	struct mbuf *mp;
1279 	int slen, s;
1280 
1281 	/*
1282 	 * Get a pointer to the data after the PPP header.
1283 	 */
1284 	if (m->m_len <= PPP_HDRLEN) {
1285 		mp = m->m_next;
1286 		if (mp == NULL)
1287 			return;
1288 		dp = mtod(mp, u_char *);
1289 	} else {
1290 		mp = m;
1291 		dp = mtod(mp, u_char *) + PPP_HDRLEN;
1292 	}
1293 
1294 	ep = mtod(mp, u_char *) + mp->m_len;
1295 	if (dp + CCP_HDRLEN > ep)
1296 		return;
1297 	slen = CCP_LENGTH(dp);
1298 	if (dp + slen > ep) {
1299 		if (sc->sc_flags & SC_DEBUG)
1300 			printf("if_ppp/ccp: not enough data in mbuf (%p+%x > %p+%x)\n",
1301 			    dp, slen, mtod(mp, u_char *), mp->m_len);
1302 		return;
1303 	}
1304 
1305 	switch (CCP_CODE(dp)) {
1306 	case CCP_CONFREQ:
1307 	case CCP_TERMREQ:
1308 	case CCP_TERMACK:
1309 		/* CCP must be going down - disable compression */
1310 		if (sc->sc_flags & SC_CCP_UP) {
1311 			s = splhigh();	/* XXX IMP ME HARDER */
1312 			sc->sc_flags &= ~(SC_CCP_UP | SC_COMP_RUN | SC_DECOMP_RUN);
1313 			splx(s);
1314 		}
1315 		break;
1316 
1317 	case CCP_CONFACK:
1318 		if (sc->sc_flags & SC_CCP_OPEN && !(sc->sc_flags & SC_CCP_UP)
1319 		    && slen >= CCP_HDRLEN + CCP_OPT_MINLEN
1320 		    && slen >= CCP_OPT_LENGTH(dp + CCP_HDRLEN) + CCP_HDRLEN) {
1321 			if (!rcvd) {
1322 				/* We're agreeing to send compressed packets. */
1323 				if (sc->sc_xc_state != NULL
1324 				    && (*sc->sc_xcomp->comp_init)
1325 				    (sc->sc_xc_state, dp + CCP_HDRLEN,
1326 					slen - CCP_HDRLEN, sc->sc_unit, 0,
1327 					sc->sc_flags & SC_DEBUG)) {
1328 					s = splhigh();	/* XXX IMP ME HARDER */
1329 					sc->sc_flags |= SC_COMP_RUN;
1330 					splx(s);
1331 				}
1332 			} else {
1333 				/*
1334 				 * Peer is agreeing to send compressed
1335 				 * packets.
1336 				 */
1337 				if (sc->sc_rc_state != NULL
1338 				    && (*sc->sc_rcomp->decomp_init)
1339 				    (sc->sc_rc_state, dp + CCP_HDRLEN, slen - CCP_HDRLEN,
1340 					sc->sc_unit, 0, sc->sc_mru,
1341 					sc->sc_flags & SC_DEBUG)) {
1342 					s = splhigh();	/* XXX IMP ME HARDER */
1343 					sc->sc_flags |= SC_DECOMP_RUN;
1344 					sc->sc_flags &= ~(SC_DC_ERROR | SC_DC_FERROR);
1345 					splx(s);
1346 				}
1347 			}
1348 		}
1349 		break;
1350 
1351 	case CCP_RESETACK:
1352 		if (sc->sc_flags & SC_CCP_UP) {
1353 			if (!rcvd) {
1354 				if (sc->sc_xc_state && (sc->sc_flags & SC_COMP_RUN))
1355 					(*sc->sc_xcomp->comp_reset)(sc->sc_xc_state);
1356 			} else {
1357 				if (sc->sc_rc_state && (sc->sc_flags & SC_DECOMP_RUN)) {
1358 					(*sc->sc_rcomp->decomp_reset)(sc->sc_rc_state);
1359 					s = splhigh();	/* XXX IMP ME HARDER */
1360 					sc->sc_flags &= ~SC_DC_ERROR;
1361 					splx(s);
1362 				}
1363 			}
1364 		}
1365 		break;
1366 	}
1367 }
1368 
1369 /*
1370  * CCP is down; free (de)compressor state if necessary.
1371  */
1372 static void
1373 ppp_ccp_closed(struct ppp_softc *sc)
1374 {
1375 	if (sc->sc_xc_state) {
1376 		(*sc->sc_xcomp->comp_free)(sc->sc_xc_state);
1377 		ppp_compressor_rele(sc->sc_xcomp);
1378 		sc->sc_xc_state = NULL;
1379 	}
1380 	if (sc->sc_rc_state) {
1381 		(*sc->sc_rcomp->decomp_free)(sc->sc_rc_state);
1382 		ppp_compressor_rele(sc->sc_rcomp);
1383 		sc->sc_rc_state = NULL;
1384 	}
1385 }
1386 #endif /* PPP_COMPRESS */
1387 
1388 /*
1389  * PPP packet input routine.
1390  * The caller has checked and removed the FCS and has inserted
1391  * the address/control bytes and the protocol high byte if they
1392  * were omitted.
1393  */
1394 void
1395 ppppktin(struct ppp_softc *sc, struct mbuf *m, int lost)
1396 {
1397 	int s = splhigh();	/* XXX IMP ME HARDER */
1398 
1399 	if (lost)
1400 		m->m_flags |= M_ERRMARK;
1401 	IF_ENQUEUE(&sc->sc_rawq, m);
1402 	softint_schedule(sc->sc_si);
1403 	splx(s);
1404 }
1405 
1406 /*
1407  * Process a received PPP packet, doing decompression as necessary.
1408  * Should be called at splsoftnet.
1409  */
1410 #define COMPTYPE(proto)	((proto) == PPP_VJC_COMP ? TYPE_COMPRESSED_TCP:	      \
1411 	    TYPE_UNCOMPRESSED_TCP)
1412 
1413 static void
1414 ppp_inproc(struct ppp_softc *sc, struct mbuf *m)
1415 {
1416 	struct ifnet *ifp = &sc->sc_if;
1417 	pktqueue_t *pktq = NULL;
1418 	struct ifqueue *inq = NULL;
1419 	int s, ilen, proto, rv;
1420 	u_char *cp, adrs, ctrl;
1421 	struct mbuf *mp, *dmp = NULL;
1422 #ifdef VJC
1423 	int xlen;
1424 	u_char *iphdr;
1425 	u_int hlen;
1426 #endif
1427 
1428 	sc->sc_stats.ppp_ipackets++;
1429 
1430 	if (sc->sc_flags & SC_LOG_INPKT) {
1431 		ilen = 0;
1432 		for (mp = m; mp != NULL; mp = mp->m_next)
1433 			ilen += mp->m_len;
1434 		printf("%s: got %d bytes\n", ifp->if_xname, ilen);
1435 		pppdumpm(m);
1436 	}
1437 
1438 	cp = mtod(m, u_char *);
1439 	adrs = PPP_ADDRESS(cp);
1440 	ctrl = PPP_CONTROL(cp);
1441 	proto = PPP_PROTOCOL(cp);
1442 
1443 	if (m->m_flags & M_ERRMARK) {
1444 		m->m_flags &= ~M_ERRMARK;
1445 		s = splhigh();	/* XXX IMP ME HARDER */
1446 		sc->sc_flags |= SC_VJ_RESET;
1447 		splx(s);
1448 	}
1449 
1450 #ifdef PPP_COMPRESS
1451 	/*
1452 	 * Decompress this packet if necessary, update the receiver's
1453 	 * dictionary, or take appropriate action on a CCP packet.
1454 	 */
1455 	if (proto == PPP_COMP && sc->sc_rc_state && (sc->sc_flags & SC_DECOMP_RUN)
1456 	    && !(sc->sc_flags & SC_DC_ERROR) && !(sc->sc_flags & SC_DC_FERROR)) {
1457 		/* Decompress this packet */
1458 		rv = (*sc->sc_rcomp->decompress)(sc->sc_rc_state, m, &dmp);
1459 		if (rv == DECOMP_OK) {
1460 			m_freem(m);
1461 			if (dmp == NULL) {
1462 				/*
1463 				 * No error, but no decompressed packet
1464 				 * produced
1465 				 */
1466 				return;
1467 			}
1468 			m = dmp;
1469 			cp = mtod(m, u_char *);
1470 			proto = PPP_PROTOCOL(cp);
1471 
1472 		} else {
1473 			/*
1474 			 * An error has occurred in decompression.
1475 			 * Pass the compressed packet up to pppd, which may
1476 			 * take CCP down or issue a Reset-Req.
1477 			 */
1478 			if (sc->sc_flags & SC_DEBUG)
1479 				printf("%s: decompress failed %d\n",
1480 				    ifp->if_xname, rv);
1481 			s = splhigh();	/* XXX IMP ME HARDER */
1482 			sc->sc_flags |= SC_VJ_RESET;
1483 			if (rv == DECOMP_ERROR)
1484 				sc->sc_flags |= SC_DC_ERROR;
1485 			else
1486 				sc->sc_flags |= SC_DC_FERROR;
1487 			splx(s);
1488 		}
1489 
1490 	} else {
1491 		if (sc->sc_rc_state && (sc->sc_flags & SC_DECOMP_RUN))
1492 			(*sc->sc_rcomp->incomp)(sc->sc_rc_state, m);
1493 		if (proto == PPP_CCP)
1494 			ppp_ccp(sc, m, 1);
1495 	}
1496 #endif
1497 
1498 	ilen = 0;
1499 	for (mp = m; mp != NULL; mp = mp->m_next)
1500 		ilen += mp->m_len;
1501 
1502 #ifdef VJC
1503 	if (sc->sc_flags & SC_VJ_RESET) {
1504 		/*
1505 		 * If we've missed a packet, we must toss subsequent compressed
1506 		 * packets which don't have an explicit connection ID.
1507 		 */
1508 		if (sc->sc_comp)
1509 			sl_uncompress_tcp(NULL, 0, TYPE_ERROR, sc->sc_comp);
1510 		s = splhigh();	/* XXX IMP ME HARDER */
1511 		sc->sc_flags &= ~SC_VJ_RESET;
1512 		splx(s);
1513 	}
1514 
1515 	/*
1516 	 * See if we have a VJ-compressed packet to uncompress.
1517 	 */
1518 	if (proto == PPP_VJC_COMP) {
1519 		if ((sc->sc_flags & SC_REJ_COMP_TCP) || sc->sc_comp == 0)
1520 			goto bad;
1521 
1522 		xlen = sl_uncompress_tcp_core(cp + PPP_HDRLEN,
1523 		    m->m_len - PPP_HDRLEN, ilen - PPP_HDRLEN,
1524 		    TYPE_COMPRESSED_TCP, sc->sc_comp, &iphdr, &hlen);
1525 
1526 		if (xlen <= 0) {
1527 			if (sc->sc_flags & SC_DEBUG)
1528 				printf("%s: VJ uncompress failed on type comp\n",
1529 				    ifp->if_xname);
1530 			goto bad;
1531 		}
1532 
1533 		/* Copy the PPP and IP headers into a new mbuf. */
1534 		MGETHDR(mp, M_DONTWAIT, MT_DATA);
1535 		if (mp == NULL)
1536 			goto bad;
1537 		mp->m_len = 0;
1538 		mp->m_next = NULL;
1539 		if (hlen + PPP_HDRLEN > MHLEN) {
1540 			MCLGET(mp, M_DONTWAIT);
1541 			if (M_TRAILINGSPACE(mp) < hlen + PPP_HDRLEN) {
1542 				/* Lose if big headers and no clusters */
1543 				m_freem(mp);
1544 				goto bad;
1545 			}
1546 		}
1547 		cp = mtod(mp, u_char *);
1548 		cp[0] = adrs;
1549 		cp[1] = ctrl;
1550 		cp[2] = 0;
1551 		cp[3] = PPP_IP;
1552 		proto = PPP_IP;
1553 		bcopy(iphdr, cp + PPP_HDRLEN, hlen);
1554 		mp->m_len = hlen + PPP_HDRLEN;
1555 
1556 		/*
1557 		 * Trim the PPP and VJ headers off the old mbuf
1558 		 * and stick the new and old mbufs together.
1559 		 */
1560 		m->m_data += PPP_HDRLEN + xlen;
1561 		m->m_len -= PPP_HDRLEN + xlen;
1562 		if (m->m_len <= M_TRAILINGSPACE(mp)) {
1563 			bcopy(mtod(m, u_char *),
1564 			    mtod(mp, u_char *) + mp->m_len, m->m_len);
1565 			mp->m_len += m->m_len;
1566 			MFREE(m, mp->m_next);
1567 		} else
1568 			mp->m_next = m;
1569 		m = mp;
1570 		ilen += hlen - xlen;
1571 
1572 	} else if (proto == PPP_VJC_UNCOMP) {
1573 		if ((sc->sc_flags & SC_REJ_COMP_TCP) || sc->sc_comp == 0)
1574 			goto bad;
1575 
1576 		xlen = sl_uncompress_tcp_core(cp + PPP_HDRLEN,
1577 		    m->m_len - PPP_HDRLEN, ilen - PPP_HDRLEN,
1578 		    TYPE_UNCOMPRESSED_TCP, sc->sc_comp, &iphdr, &hlen);
1579 
1580 		if (xlen < 0) {
1581 			if (sc->sc_flags & SC_DEBUG)
1582 				printf("%s: VJ uncompress failed on type uncomp\n",
1583 				    ifp->if_xname);
1584 			goto bad;
1585 		}
1586 
1587 		proto = PPP_IP;
1588 		cp[3] = PPP_IP;
1589 	}
1590 #endif /* VJC */
1591 
1592 	/*
1593 	 * If the packet will fit in a header mbuf, don't waste a
1594 	 * whole cluster on it.
1595 	 */
1596 	if (ilen <= MHLEN && M_IS_CLUSTER(m)) {
1597 		MGETHDR(mp, M_DONTWAIT, MT_DATA);
1598 		if (mp != NULL) {
1599 			m_copydata(m, 0, ilen, mtod(mp, void *));
1600 			m_freem(m);
1601 			m = mp;
1602 			m->m_len = ilen;
1603 		}
1604 	}
1605 	m->m_pkthdr.len = ilen;
1606 	m->m_pkthdr.rcvif = ifp;
1607 
1608 	if ((proto & 0x8000) == 0) {
1609 #ifdef PPP_FILTER
1610 		/*
1611 		 * See whether we want to pass this packet, and
1612 		 * if it counts as link activity.
1613 		 */
1614 		if (sc->sc_pass_filt_in.bf_insns != 0
1615 		    && bpf_filter(sc->sc_pass_filt_in.bf_insns,
1616 			(u_char *)m, ilen, 0) == 0) {
1617 			/* drop this packet */
1618 			m_freem(m);
1619 			return;
1620 		}
1621 		if (sc->sc_active_filt_in.bf_insns == 0
1622 		    || bpf_filter(sc->sc_active_filt_in.bf_insns,
1623 			(u_char *)m, ilen, 0))
1624 			sc->sc_last_recv = time_second;
1625 #else
1626 		/*
1627 		 * Record the time that we received this packet.
1628 		 */
1629 		sc->sc_last_recv = time_second;
1630 #endif /* PPP_FILTER */
1631 	}
1632 
1633 	/* See if bpf wants to look at the packet. */
1634 	bpf_mtap(&sc->sc_if, m);
1635 
1636 	switch (proto) {
1637 #ifdef INET
1638 	case PPP_IP:
1639 		/*
1640 		 * IP packet - take off the ppp header and pass it up to IP.
1641 		 */
1642 		if ((ifp->if_flags & IFF_UP) == 0
1643 		    || sc->sc_npmode[NP_IP] != NPMODE_PASS) {
1644 			/* Interface is down - drop the packet. */
1645 			m_freem(m);
1646 			return;
1647 		}
1648 		m->m_pkthdr.len -= PPP_HDRLEN;
1649 		m->m_data += PPP_HDRLEN;
1650 		m->m_len -= PPP_HDRLEN;
1651 #ifdef GATEWAY
1652 		if (ipflow_fastforward(m))
1653 			return;
1654 #endif
1655 		pktq = ip_pktq;
1656 		break;
1657 #endif
1658 
1659 #ifdef INET6
1660 	case PPP_IPV6:
1661 		/*
1662 		 * IPv6 packet - take off the ppp header and pass it up to
1663 		 * IPv6.
1664 		 */
1665 		if ((ifp->if_flags & IFF_UP) == 0
1666 		    || sc->sc_npmode[NP_IPV6] != NPMODE_PASS) {
1667 			/* interface is down - drop the packet. */
1668 			m_freem(m);
1669 			return;
1670 		}
1671 		m->m_pkthdr.len -= PPP_HDRLEN;
1672 		m->m_data += PPP_HDRLEN;
1673 		m->m_len -= PPP_HDRLEN;
1674 #ifdef GATEWAY
1675 		if (ip6flow_fastforward(&m))
1676 			return;
1677 #endif
1678 		pktq = ip6_pktq;
1679 		break;
1680 #endif
1681 
1682 	default:
1683 		/*
1684 		 * Some other protocol - place on input queue for read().
1685 		 */
1686 		inq = &sc->sc_inq;
1687 		pktq = NULL;
1688 		break;
1689 	}
1690 
1691 	/*
1692 	 * Put the packet on the appropriate input queue.
1693 	 */
1694 	s = splnet();
1695 
1696 	/* pktq: inet or inet6 cases */
1697 	if (__predict_true(pktq)) {
1698 		if (__predict_false(!pktq_enqueue(pktq, m, 0))) {
1699 			ifp->if_iqdrops++;
1700 			goto bad;
1701 		}
1702 		ifp->if_ipackets++;
1703 		ifp->if_ibytes += ilen;
1704 		splx(s);
1705 		return;
1706 	}
1707 
1708 	/* ifq: other protocol cases */
1709 	if (!inq) {
1710 		goto bad;
1711 	}
1712 	if (IF_QFULL(inq)) {
1713 		IF_DROP(inq);
1714 		splx(s);
1715 		if (sc->sc_flags & SC_DEBUG)
1716 			printf("%s: input queue full\n", ifp->if_xname);
1717 		ifp->if_iqdrops++;
1718 		goto bad;
1719 	}
1720 	IF_ENQUEUE(inq, m);
1721 	splx(s);
1722 	ifp->if_ipackets++;
1723 	ifp->if_ibytes += ilen;
1724 
1725 	(*sc->sc_ctlp)(sc);
1726 
1727 	return;
1728 
1729 bad:
1730 	m_freem(m);
1731 	sc->sc_if.if_ierrors++;
1732 	sc->sc_stats.ppp_ierrors++;
1733 }
1734 
1735 #define MAX_DUMP_BYTES	128
1736 
1737 static void
1738 pppdumpm(struct mbuf *m0)
1739 {
1740 	char buf[3*MAX_DUMP_BYTES+4];
1741 	char *bp = buf;
1742 	struct mbuf *m;
1743 
1744 	for (m = m0; m; m = m->m_next) {
1745 		int l = m->m_len;
1746 		u_char *rptr = (u_char *)m->m_data;
1747 
1748 		while (l--) {
1749 			if (bp > buf + sizeof(buf) - 4)
1750 				goto done;
1751 			/* Convert byte to ascii hex */
1752 			*bp++ = hexdigits[*rptr >> 4];
1753 			*bp++ = hexdigits[*rptr++ & 0xf];
1754 		}
1755 
1756 		if (m->m_next) {
1757 			if (bp > buf + sizeof(buf) - 3)
1758 				goto done;
1759 			*bp++ = '|';
1760 		} else
1761 			*bp++ = ' ';
1762 	}
1763 done:
1764 	if (m)
1765 		*bp++ = '>';
1766 	*bp = 0;
1767 	printf("%s\n", buf);
1768 }
1769 
1770 #ifdef ALTQ
1771 /*
1772  * A wrapper to transmit a packet from if_start since ALTQ uses
1773  * if_start to send a packet.
1774  */
1775 static void
1776 ppp_ifstart(struct ifnet *ifp)
1777 {
1778 	struct ppp_softc *sc;
1779 
1780 	sc = ifp->if_softc;
1781 	(*sc->sc_start)(sc);
1782 }
1783 #endif
1784 
1785 static const struct ppp_known_compressor {
1786 	uint8_t code;
1787 	const char *module;
1788 } ppp_known_compressors[] = {
1789 	{ CI_DEFLATE, "ppp_deflate" },
1790 	{ CI_DEFLATE_DRAFT, "ppp_deflate" },
1791 	{ CI_BSD_COMPRESS, "ppp_bsdcomp" },
1792 	{ CI_MPPE, "ppp_mppe" },
1793 	{ 0, NULL }
1794 };
1795 
1796 static int
1797 ppp_compressor_init(void)
1798 {
1799 
1800 	mutex_init(&ppp_compressors_mtx, MUTEX_DEFAULT, IPL_NONE);
1801 	return 0;
1802 }
1803 
1804 static void
1805 ppp_compressor_rele(struct compressor *cp)
1806 {
1807 
1808 	mutex_enter(&ppp_compressors_mtx);
1809 	--cp->comp_refcnt;
1810 	mutex_exit(&ppp_compressors_mtx);
1811 }
1812 
1813 static struct compressor *
1814 ppp_get_compressor_noload(uint8_t ci, bool hold)
1815 {
1816 	struct compressor *cp;
1817 
1818 	KASSERT(mutex_owned(&ppp_compressors_mtx));
1819 	LIST_FOREACH(cp, &ppp_compressors, comp_list) {
1820 		if (cp->compress_proto == ci) {
1821 			if (hold)
1822 				++cp->comp_refcnt;
1823 			return cp;
1824 		}
1825 	}
1826 
1827 	return NULL;
1828 }
1829 
1830 static struct compressor *
1831 ppp_get_compressor(uint8_t ci)
1832 {
1833 	struct compressor *cp = NULL;
1834 	const struct ppp_known_compressor *pkc;
1835 
1836 	mutex_enter(&ppp_compressors_mtx);
1837 	cp = ppp_get_compressor_noload(ci, true);
1838 	mutex_exit(&ppp_compressors_mtx);
1839 	if (cp != NULL)
1840 		return cp;
1841 
1842 	kernconfig_lock();
1843 	mutex_enter(&ppp_compressors_mtx);
1844 	cp = ppp_get_compressor_noload(ci, true);
1845 	mutex_exit(&ppp_compressors_mtx);
1846 	if (cp == NULL) {
1847 		/* Not found, so try to autoload a module */
1848 		for (pkc = ppp_known_compressors; pkc->module != NULL; pkc++) {
1849 			if (pkc->code == ci) {
1850 				if (module_autoload(pkc->module,
1851 					MODULE_CLASS_MISC) != 0)
1852 					break;
1853 				mutex_enter(&ppp_compressors_mtx);
1854 				cp = ppp_get_compressor_noload(ci, true);
1855 				mutex_exit(&ppp_compressors_mtx);
1856 				break;
1857 			}
1858 		}
1859 	}
1860 	kernconfig_unlock();
1861 
1862 	return cp;
1863 }
1864 
1865 int
1866 ppp_register_compressor(struct compressor *pc, size_t ncomp)
1867 {
1868 	int error = 0;
1869 	size_t i;
1870 
1871 	RUN_ONCE(&ppp_compressor_mtx_init, ppp_compressor_init);
1872 
1873 	mutex_enter(&ppp_compressors_mtx);
1874 	for (i = 0; i < ncomp; i++) {
1875 		if (ppp_get_compressor_noload(pc[i].compress_proto,
1876 			false) != NULL)
1877 			error = EEXIST;
1878 	}
1879 	if (!error) {
1880 		for (i = 0; i < ncomp; i++) {
1881 			pc[i].comp_refcnt = 0;
1882 			LIST_INSERT_HEAD(&ppp_compressors, &pc[i], comp_list);
1883 		}
1884 	}
1885 	mutex_exit(&ppp_compressors_mtx);
1886 
1887 	return error;
1888 }
1889 
1890 int
1891 ppp_unregister_compressor(struct compressor *pc, size_t ncomp)
1892 {
1893 	int error = 0;
1894 	size_t i;
1895 
1896 	mutex_enter(&ppp_compressors_mtx);
1897 	for (i = 0; i < ncomp; i++) {
1898 		if (ppp_get_compressor_noload(pc[i].compress_proto,
1899 			false) != &pc[i])
1900 			error = ENOENT;
1901 		else if (pc[i].comp_refcnt != 0)
1902 			error = EBUSY;
1903 	}
1904 	if (!error) {
1905 		for (i = 0; i < ncomp; i++) {
1906 			LIST_REMOVE(&pc[i], comp_list);
1907 		}
1908 	}
1909 	mutex_exit(&ppp_compressors_mtx);
1910 
1911 	return error;
1912 }
1913