xref: /netbsd-src/sys/net/if_ppp.c (revision e5548b402ae4c44fb816de42c7bba9581ce23ef5)
1 /*	$NetBSD: if_ppp.c,v 1.103 2005/12/11 23:05:25 thorpej 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 1.103 2005/12/11 23:05:25 thorpej Exp $");
106 
107 #include "ppp.h"
108 
109 #include "opt_inet.h"
110 #include "opt_gateway.h"
111 #include "opt_ppp.h"
112 
113 #ifdef INET
114 #define VJC
115 #endif
116 #define PPP_COMPRESS
117 
118 #include <sys/param.h>
119 #include <sys/proc.h>
120 #include <sys/mbuf.h>
121 #include <sys/socket.h>
122 #include <sys/ioctl.h>
123 #include <sys/kernel.h>
124 #include <sys/systm.h>
125 #include <sys/time.h>
126 #include <sys/malloc.h>
127 #include <sys/conf.h>
128 
129 #include <net/if.h>
130 #include <net/if_types.h>
131 #include <net/netisr.h>
132 #include <net/route.h>
133 #ifdef PPP_FILTER
134 #include <net/bpf.h>
135 #endif
136 
137 #include <machine/intr.h>
138 
139 #include <netinet/in.h>
140 #include <netinet/in_systm.h>
141 #include <netinet/in_var.h>
142 #ifdef INET
143 #include <netinet/ip.h>
144 #endif
145 
146 #include "bpfilter.h"
147 #if NBPFILTER > 0
148 #include <sys/time.h>
149 #include <net/bpf.h>
150 #endif
151 
152 #if defined(PPP_FILTER) || NBPFILTER > 0
153 #include <net/slip.h>
154 #endif
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 <machine/cpu.h>
164 
165 #ifdef PPP_COMPRESS
166 #define PACKETPTR	struct mbuf *
167 #include <net/ppp-comp.h>
168 #endif
169 
170 static int	pppsioctl(struct ifnet *, u_long, caddr_t);
171 static void	ppp_requeue(struct ppp_softc *);
172 static void	ppp_ccp(struct ppp_softc *, struct mbuf *m, int rcvd);
173 static void	ppp_ccp_closed(struct ppp_softc *);
174 static void	ppp_inproc(struct ppp_softc *, struct mbuf *);
175 static void	pppdumpm(struct mbuf *m0);
176 #ifdef ALTQ
177 static void	ppp_ifstart(struct ifnet *ifp);
178 #endif
179 
180 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS
181 void		pppnetisr(void);
182 #endif
183 static void	pppintr(void *);
184 
185 /*
186  * Some useful mbuf macros not in mbuf.h.
187  */
188 #define M_IS_CLUSTER(m)	((m)->m_flags & M_EXT)
189 
190 #define M_DATASTART(m)	\
191 	(M_IS_CLUSTER(m) ? (m)->m_ext.ext_buf : \
192 	    (m)->m_flags & M_PKTHDR ? (m)->m_pktdat : (m)->m_dat)
193 
194 #define M_DATASIZE(m)	\
195 	(M_IS_CLUSTER(m) ? (m)->m_ext.ext_size : \
196 	    (m)->m_flags & M_PKTHDR ? MHLEN: MLEN)
197 
198 /*
199  * We define two link layer specific mbuf flags, to mark high-priority
200  * packets for output, and received packets following lost/corrupted
201  * packets.
202  */
203 #define	M_HIGHPRI	M_LINK0	/* output packet for sc_fastq */
204 #define	M_ERRMARK	M_LINK1	/* rx packet following lost/corrupted pkt */
205 
206 static int		ppp_clone_create(struct if_clone *, int);
207 static int		ppp_clone_destroy(struct ifnet *);
208 
209 static struct ppp_softc *ppp_create(const char *, int);
210 
211 static LIST_HEAD(, ppp_softc) ppp_softc_list;
212 
213 struct if_clone ppp_cloner =
214     IF_CLONE_INITIALIZER("ppp", ppp_clone_create, ppp_clone_destroy);
215 
216 static struct simplelock ppp_list_mutex = SIMPLELOCK_INITIALIZER;
217 
218 #ifdef PPP_COMPRESS
219 /*
220  * List of compressors we know about.
221  * We leave some space so maybe we can modload compressors.
222  */
223 
224 extern struct compressor ppp_bsd_compress;
225 extern struct compressor ppp_deflate, ppp_deflate_draft;
226 
227 struct compressor *ppp_compressors[PPP_COMPRESSORS_MAX] = {
228 #if DO_BSD_COMPRESS && defined(PPP_BSDCOMP)
229     &ppp_bsd_compress,
230 #endif
231 #if DO_DEFLATE && defined(PPP_DEFLATE)
232     &ppp_deflate,
233     &ppp_deflate_draft,
234 #endif
235     NULL
236 };
237 #endif /* PPP_COMPRESS */
238 
239 
240 /*
241  * Called from boot code to establish ppp interfaces.
242  */
243 void
244 pppattach(void)
245 {
246     extern struct linesw ppp_disc;
247 
248     if (ttyldisc_attach(&ppp_disc) != 0)
249     	panic("pppattach");
250     LIST_INIT(&ppp_softc_list);
251     if_clone_attach(&ppp_cloner);
252 }
253 
254 static struct ppp_softc *
255 ppp_create(const char *name, int unit)
256 {
257     struct ppp_softc *sc, *sci, *scl = NULL;
258 
259     MALLOC(sc, struct ppp_softc *, sizeof(*sc), M_DEVBUF, M_WAIT|M_ZERO);
260 
261     simple_lock(&ppp_list_mutex);
262     if (unit == -1) {
263 	int i = 0;
264 	LIST_FOREACH(sci, &ppp_softc_list, sc_iflist) {
265 	    scl = sci;
266 	    if (i < sci->sc_unit) {
267 		unit = i;
268 		break;
269 	    } else {
270 #ifdef DIAGNOSTIC
271 		KASSERT(i == sci->sc_unit);
272 #endif
273 		i++;
274 	    }
275 	}
276 	if (unit == -1)
277 	    unit = i;
278     } else {
279 	LIST_FOREACH(sci, &ppp_softc_list, sc_iflist) {
280 	    scl = sci;
281 	    if (unit < sci->sc_unit)
282 		break;
283 	    else if (unit == sci->sc_unit) {
284 		FREE(sc, M_DEVBUF);
285 		return NULL;
286 	    }
287 	}
288     }
289 
290     if (sci != NULL)
291 	LIST_INSERT_BEFORE(sci, sc, sc_iflist);
292     else if (scl != NULL)
293 	LIST_INSERT_AFTER(scl, sc, sc_iflist);
294     else
295 	LIST_INSERT_HEAD(&ppp_softc_list, sc, sc_iflist);
296 
297     simple_unlock(&ppp_list_mutex);
298 
299     (void)snprintf(sc->sc_if.if_xname, sizeof(sc->sc_if.if_xname), "%s%d",
300 	name, sc->sc_unit = unit);
301     callout_init(&sc->sc_timo_ch);
302     sc->sc_if.if_softc = sc;
303     sc->sc_if.if_mtu = PPP_MTU;
304     sc->sc_if.if_flags = IFF_POINTOPOINT | IFF_MULTICAST;
305     sc->sc_if.if_type = IFT_PPP;
306     sc->sc_if.if_hdrlen = PPP_HDRLEN;
307     sc->sc_if.if_dlt = DLT_NULL;
308     sc->sc_if.if_ioctl = pppsioctl;
309     sc->sc_if.if_output = pppoutput;
310 #ifdef ALTQ
311     sc->sc_if.if_start = ppp_ifstart;
312 #endif
313     IFQ_SET_MAXLEN(&sc->sc_if.if_snd, IFQ_MAXLEN);
314     sc->sc_inq.ifq_maxlen = IFQ_MAXLEN;
315     sc->sc_fastq.ifq_maxlen = IFQ_MAXLEN;
316     sc->sc_rawq.ifq_maxlen = IFQ_MAXLEN;
317     IFQ_SET_READY(&sc->sc_if.if_snd);
318     if_attach(&sc->sc_if);
319     if_alloc_sadl(&sc->sc_if);
320 #if NBPFILTER > 0
321     bpfattach(&sc->sc_if, DLT_NULL, 0);
322 #endif
323     return sc;
324 }
325 
326 static int
327 ppp_clone_create(struct if_clone *ifc, int unit)
328 {
329     return ppp_create(ifc->ifc_name, unit) == NULL ? EEXIST : 0;
330 }
331 
332 static int
333 ppp_clone_destroy(struct ifnet *ifp)
334 {
335     struct ppp_softc *sc = (struct ppp_softc *)ifp->if_softc;
336 
337     if (sc->sc_devp != NULL)
338 	return EBUSY; /* Not removing it */
339 
340     simple_lock(&ppp_list_mutex);
341     LIST_REMOVE(sc, sc_iflist);
342     simple_unlock(&ppp_list_mutex);
343 
344 #if NBPFILTER > 0
345     bpfdetach(ifp);
346 #endif
347     if_detach(ifp);
348 
349     FREE(sc, M_DEVBUF);
350     return 0;
351 }
352 
353 /*
354  * Allocate a ppp interface unit and initialize it.
355  */
356 struct ppp_softc *
357 pppalloc(pid_t pid)
358 {
359     struct ppp_softc *sc = NULL, *scf;
360     int i;
361 
362     simple_lock(&ppp_list_mutex);
363     for (scf = LIST_FIRST(&ppp_softc_list); scf != NULL;
364 	scf = LIST_NEXT(scf, sc_iflist)) {
365 	if (scf->sc_xfer == pid) {
366 	    scf->sc_xfer = 0;
367 	    simple_unlock(&ppp_list_mutex);
368 	    return scf;
369 	}
370 	if (scf->sc_devp == NULL && sc == NULL)
371 	    sc = scf;
372     }
373     simple_unlock(&ppp_list_mutex);
374 
375     if (sc == NULL)
376 	sc = ppp_create(ppp_cloner.ifc_name, -1);
377 
378 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
379     sc->sc_si = softintr_establish(IPL_SOFTNET, pppintr, sc);
380     if (sc->sc_si == NULL) {
381 	printf("%s: unable to establish softintr\n", sc->sc_if.if_xname);
382 	return (NULL);
383     }
384 #endif
385     sc->sc_flags = 0;
386     sc->sc_mru = PPP_MRU;
387     sc->sc_relinq = NULL;
388     (void)memset(&sc->sc_stats, 0, sizeof(sc->sc_stats));
389 #ifdef VJC
390     MALLOC(sc->sc_comp, struct slcompress *, sizeof(struct slcompress),
391 	   M_DEVBUF, M_NOWAIT);
392     if (sc->sc_comp)
393 	sl_compress_init(sc->sc_comp);
394 #endif
395 #ifdef PPP_COMPRESS
396     sc->sc_xc_state = NULL;
397     sc->sc_rc_state = NULL;
398 #endif /* PPP_COMPRESS */
399     for (i = 0; i < NUM_NP; ++i)
400 	sc->sc_npmode[i] = NPMODE_ERROR;
401     sc->sc_npqueue = NULL;
402     sc->sc_npqtail = &sc->sc_npqueue;
403     sc->sc_last_sent = sc->sc_last_recv = time.tv_sec;
404 
405     return sc;
406 }
407 
408 /*
409  * Deallocate a ppp unit.  Must be called at splsoftnet or higher.
410  */
411 void
412 pppdealloc(struct ppp_softc *sc)
413 {
414     struct mbuf *m;
415 
416 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
417     softintr_disestablish(sc->sc_si);
418 #endif
419     if_down(&sc->sc_if);
420     sc->sc_if.if_flags &= ~(IFF_UP|IFF_RUNNING);
421     sc->sc_devp = NULL;
422     sc->sc_xfer = 0;
423     for (;;) {
424 	IF_DEQUEUE(&sc->sc_rawq, m);
425 	if (m == NULL)
426 	    break;
427 	m_freem(m);
428     }
429     for (;;) {
430 	IF_DEQUEUE(&sc->sc_inq, m);
431 	if (m == NULL)
432 	    break;
433 	m_freem(m);
434     }
435     for (;;) {
436 	IF_DEQUEUE(&sc->sc_fastq, m);
437 	if (m == NULL)
438 	    break;
439 	m_freem(m);
440     }
441     while ((m = sc->sc_npqueue) != NULL) {
442 	sc->sc_npqueue = m->m_nextpkt;
443 	m_freem(m);
444     }
445     if (sc->sc_togo != NULL) {
446 	m_freem(sc->sc_togo);
447 	sc->sc_togo = NULL;
448     }
449 #ifdef PPP_COMPRESS
450     ppp_ccp_closed(sc);
451     sc->sc_xc_state = NULL;
452     sc->sc_rc_state = NULL;
453 #endif /* PPP_COMPRESS */
454 #ifdef PPP_FILTER
455     if (sc->sc_pass_filt_in.bf_insns != 0) {
456 	FREE(sc->sc_pass_filt_in.bf_insns, M_DEVBUF);
457 	sc->sc_pass_filt_in.bf_insns = 0;
458 	sc->sc_pass_filt_in.bf_len = 0;
459     }
460     if (sc->sc_pass_filt_out.bf_insns != 0) {
461 	FREE(sc->sc_pass_filt_out.bf_insns, M_DEVBUF);
462 	sc->sc_pass_filt_out.bf_insns = 0;
463 	sc->sc_pass_filt_out.bf_len = 0;
464     }
465     if (sc->sc_active_filt_in.bf_insns != 0) {
466 	FREE(sc->sc_active_filt_in.bf_insns, M_DEVBUF);
467 	sc->sc_active_filt_in.bf_insns = 0;
468 	sc->sc_active_filt_in.bf_len = 0;
469     }
470     if (sc->sc_active_filt_out.bf_insns != 0) {
471 	FREE(sc->sc_active_filt_out.bf_insns, M_DEVBUF);
472 	sc->sc_active_filt_out.bf_insns = 0;
473 	sc->sc_active_filt_out.bf_len = 0;
474     }
475 #endif /* PPP_FILTER */
476 #ifdef VJC
477     if (sc->sc_comp != 0) {
478 	FREE(sc->sc_comp, M_DEVBUF);
479 	sc->sc_comp = 0;
480     }
481 #endif
482     (void)ppp_clone_destroy(&sc->sc_if);
483 }
484 
485 /*
486  * Ioctl routine for generic ppp devices.
487  */
488 int
489 pppioctl(struct ppp_softc *sc, u_long cmd, caddr_t data, int flag,
490          struct proc *p)
491 {
492     int s, error, flags, mru, npx;
493     u_int nb;
494     struct ppp_option_data *odp;
495     struct compressor **cp;
496     struct npioctl *npi;
497     time_t t;
498 #ifdef PPP_FILTER
499     struct bpf_program *bp, *nbp;
500     struct bpf_insn *newcode, *oldcode;
501     int newcodelen;
502 #endif /* PPP_FILTER */
503 #ifdef	PPP_COMPRESS
504     u_char ccp_option[CCP_MAX_OPTION_LENGTH];
505 #endif
506 
507     switch (cmd) {
508     case FIONREAD:
509 	*(int *)data = sc->sc_inq.ifq_len;
510 	break;
511 
512     case PPPIOCGUNIT:
513 	*(int *)data = sc->sc_unit;
514 	break;
515 
516     case PPPIOCGFLAGS:
517 	*(u_int *)data = sc->sc_flags;
518 	break;
519 
520     case PPPIOCGRAWIN:
521 	{
522 	    struct ppp_rawin *rwin = (struct ppp_rawin *)data;
523 	    u_char c, q = 0;
524 
525 	    for (c = sc->sc_rawin_start; c < sizeof(sc->sc_rawin.buf);)
526 		rwin->buf[q++] = sc->sc_rawin.buf[c++];
527 
528 	    for (c = 0; c < sc->sc_rawin_start;)
529 		rwin->buf[q++] = sc->sc_rawin.buf[c++];
530 
531 	    rwin->count = sc->sc_rawin.count;
532 	}
533 	break;
534 
535     case PPPIOCSFLAGS:
536 	if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
537 	    return (error);
538 	flags = *(int *)data & SC_MASK;
539 	s = splsoftnet();
540 #ifdef PPP_COMPRESS
541 	if (sc->sc_flags & SC_CCP_OPEN && !(flags & SC_CCP_OPEN))
542 	    ppp_ccp_closed(sc);
543 #endif
544 	splhigh();	/* XXX IMP ME HARDER */
545 	sc->sc_flags = (sc->sc_flags & ~SC_MASK) | flags;
546 	splx(s);
547 	break;
548 
549     case PPPIOCSMRU:
550 	if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
551 	    return (error);
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 ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
564 	    return (error);
565 	if (sc->sc_comp) {
566 	    s = splsoftnet();
567 	    sl_compress_setup(sc->sc_comp, *(int *)data);
568 	    splx(s);
569 	}
570 	break;
571 #endif
572 
573     case PPPIOCXFERUNIT:
574 	if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
575 	    return (error);
576 	sc->sc_xfer = p->p_pid;
577 	break;
578 
579 #ifdef PPP_COMPRESS
580     case PPPIOCSCOMPRESS:
581 	if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
582 	    return (error);
583 	odp = (struct ppp_option_data *) data;
584 	nb = odp->length;
585 	if (nb > sizeof(ccp_option))
586 	    nb = sizeof(ccp_option);
587 	if ((error = copyin(odp->ptr, ccp_option, nb)) != 0)
588 	    return (error);
589 	if (ccp_option[1] < 2)	/* preliminary check on the length byte */
590 	    return (EINVAL);
591 	for (cp = ppp_compressors; *cp != NULL; ++cp)
592 	    if ((*cp)->compress_proto == ccp_option[0]) {
593 		/*
594 		 * Found a handler for the protocol - try to allocate
595 		 * a compressor or decompressor.
596 		 */
597 		error = 0;
598 		if (odp->transmit) {
599 		    s = splsoftnet();
600 		    if (sc->sc_xc_state != NULL)
601 			(*sc->sc_xcomp->comp_free)(sc->sc_xc_state);
602 		    sc->sc_xcomp = *cp;
603 		    sc->sc_xc_state = (*cp)->comp_alloc(ccp_option, nb);
604 		    if (sc->sc_xc_state == NULL) {
605 			if (sc->sc_flags & SC_DEBUG)
606 			    printf("%s: comp_alloc failed\n",
607 				sc->sc_if.if_xname);
608 			error = ENOBUFS;
609 		    }
610 		    splhigh();	/* XXX IMP ME HARDER */
611 		    sc->sc_flags &= ~SC_COMP_RUN;
612 		    splx(s);
613 		} else {
614 		    s = splsoftnet();
615 		    if (sc->sc_rc_state != NULL)
616 			(*sc->sc_rcomp->decomp_free)(sc->sc_rc_state);
617 		    sc->sc_rcomp = *cp;
618 		    sc->sc_rc_state = (*cp)->decomp_alloc(ccp_option, nb);
619 		    if (sc->sc_rc_state == NULL) {
620 			if (sc->sc_flags & SC_DEBUG)
621 			    printf("%s: decomp_alloc failed\n",
622 				sc->sc_if.if_xname);
623 			error = ENOBUFS;
624 		    }
625 		    splhigh();	/* XXX IMP ME HARDER */
626 		    sc->sc_flags &= ~SC_DECOMP_RUN;
627 		    splx(s);
628 		}
629 		return (error);
630 	    }
631 	if (sc->sc_flags & SC_DEBUG)
632 	    printf("%s: no compressor for [%x %x %x], %x\n",
633 		sc->sc_if.if_xname, ccp_option[0], ccp_option[1],
634 		ccp_option[2], nb);
635 	return (EINVAL);	/* no handler found */
636 #endif /* PPP_COMPRESS */
637 
638     case PPPIOCGNPMODE:
639     case PPPIOCSNPMODE:
640 	npi = (struct npioctl *) data;
641 	switch (npi->protocol) {
642 	case PPP_IP:
643 	    npx = NP_IP;
644 	    break;
645 	case PPP_IPV6:
646 	    npx = NP_IPV6;
647 	    break;
648 	default:
649 	    return EINVAL;
650 	}
651 	if (cmd == PPPIOCGNPMODE) {
652 	    npi->mode = sc->sc_npmode[npx];
653 	} else {
654 	    if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
655 		return (error);
656 	    if (npi->mode != sc->sc_npmode[npx]) {
657 		s = splnet();
658 		sc->sc_npmode[npx] = npi->mode;
659 		if (npi->mode != NPMODE_QUEUE) {
660 		    ppp_requeue(sc);
661 		    ppp_restart(sc);
662 		}
663 		splx(s);
664 	    }
665 	}
666 	break;
667 
668     case PPPIOCGIDLE:
669 	s = splsoftnet();
670 	t = time.tv_sec;
671 	((struct ppp_idle *)data)->xmit_idle = t - sc->sc_last_sent;
672 	((struct ppp_idle *)data)->recv_idle = t - sc->sc_last_recv;
673 	splx(s);
674 	break;
675 
676 #ifdef PPP_FILTER
677     case PPPIOCSPASS:
678     case PPPIOCSACTIVE:
679 	/* These are no longer supported. */
680 	return EOPNOTSUPP;
681 
682     case PPPIOCSIPASS:
683     case PPPIOCSOPASS:
684     case PPPIOCSIACTIVE:
685     case PPPIOCSOACTIVE:
686 	nbp = (struct bpf_program *) data;
687 	if ((unsigned) nbp->bf_len > BPF_MAXINSNS)
688 	    return EINVAL;
689 	newcodelen = nbp->bf_len * sizeof(struct bpf_insn);
690 	if (newcodelen != 0) {
691 	    newcode = malloc(newcodelen, M_DEVBUF, M_WAITOK);
692 	    /* WAITOK -- malloc() never fails. */
693 	    if ((error = copyin((caddr_t)nbp->bf_insns, (caddr_t)newcode,
694 			       newcodelen)) != 0) {
695 		free(newcode, M_DEVBUF);
696 		return error;
697 	    }
698 	    if (!bpf_validate(newcode, nbp->bf_len)) {
699 		free(newcode, M_DEVBUF);
700 		return EINVAL;
701 	    }
702 	} else
703 	    newcode = 0;
704 	switch (cmd) {
705 	case PPPIOCSIPASS:
706 	    bp = &sc->sc_pass_filt_in;
707 	    break;
708 
709 	case PPPIOCSOPASS:
710 	    bp = &sc->sc_pass_filt_out;
711 	    break;
712 
713 	case PPPIOCSIACTIVE:
714 	    bp = &sc->sc_active_filt_in;
715 	    break;
716 
717 	case PPPIOCSOACTIVE:
718 	    bp = &sc->sc_active_filt_out;
719 	    break;
720 	default:
721 	    free(newcode, M_DEVBUF);
722 	    return (EPASSTHROUGH);
723 	}
724 	oldcode = bp->bf_insns;
725 	s = splnet();
726 	bp->bf_len = nbp->bf_len;
727 	bp->bf_insns = newcode;
728 	splx(s);
729 	if (oldcode != 0)
730 	    free(oldcode, M_DEVBUF);
731 	break;
732 #endif /* PPP_FILTER */
733 
734     default:
735 	return (EPASSTHROUGH);
736     }
737     return (0);
738 }
739 
740 /*
741  * Process an ioctl request to the ppp network interface.
742  */
743 static int
744 pppsioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
745 {
746     struct proc *p = curproc;	/* XXX */
747     struct ppp_softc *sc = ifp->if_softc;
748     struct ifaddr *ifa = (struct ifaddr *)data;
749     struct ifreq *ifr = (struct ifreq *)data;
750     struct ppp_stats *psp;
751 #ifdef	PPP_COMPRESS
752     struct ppp_comp_stats *pcp;
753 #endif
754     int s = splnet(), error = 0;
755 
756     switch (cmd) {
757     case SIOCSIFFLAGS:
758 	if ((ifp->if_flags & IFF_RUNNING) == 0)
759 	    ifp->if_flags &= ~IFF_UP;
760 	break;
761 
762     case SIOCSIFADDR:
763 	switch (ifa->ifa_addr->sa_family) {
764 #ifdef INET
765 	case AF_INET:
766 	    break;
767 #endif
768 #ifdef INET6
769 	case AF_INET6:
770 	    break;
771 #endif
772 	default:
773 	    error = EAFNOSUPPORT;
774 	    break;
775 	}
776 	break;
777 
778     case SIOCSIFDSTADDR:
779 	switch (ifa->ifa_addr->sa_family) {
780 #ifdef INET
781 	case AF_INET:
782 	    break;
783 #endif
784 #ifdef INET6
785 	case AF_INET6:
786 	    break;
787 #endif
788 	default:
789 	    error = EAFNOSUPPORT;
790 	    break;
791 	}
792 	break;
793 
794     case SIOCSIFMTU:
795 	if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
796 	    break;
797 	sc->sc_if.if_mtu = ifr->ifr_mtu;
798 	break;
799 
800     case SIOCGIFMTU:
801 	ifr->ifr_mtu = sc->sc_if.if_mtu;
802 	break;
803 
804     case SIOCADDMULTI:
805     case SIOCDELMULTI:
806 	if (ifr == 0) {
807 	    error = EAFNOSUPPORT;
808 	    break;
809 	}
810 	switch (ifr->ifr_addr.sa_family) {
811 #ifdef INET
812 	case AF_INET:
813 	    break;
814 #endif
815 #ifdef INET6
816 	case AF_INET6:
817 	    break;
818 #endif
819 	default:
820 	    error = EAFNOSUPPORT;
821 	    break;
822 	}
823 	break;
824 
825     case SIOCGPPPSTATS:
826 	psp = &((struct ifpppstatsreq *) data)->stats;
827 	memset(psp, 0, sizeof(*psp));
828 	psp->p = sc->sc_stats;
829 #if defined(VJC) && !defined(SL_NO_STATS)
830 	if (sc->sc_comp) {
831 	    psp->vj.vjs_packets = sc->sc_comp->sls_packets;
832 	    psp->vj.vjs_compressed = sc->sc_comp->sls_compressed;
833 	    psp->vj.vjs_searches = sc->sc_comp->sls_searches;
834 	    psp->vj.vjs_misses = sc->sc_comp->sls_misses;
835 	    psp->vj.vjs_uncompressedin = sc->sc_comp->sls_uncompressedin;
836 	    psp->vj.vjs_compressedin = sc->sc_comp->sls_compressedin;
837 	    psp->vj.vjs_errorin = sc->sc_comp->sls_errorin;
838 	    psp->vj.vjs_tossed = sc->sc_comp->sls_tossed;
839 	}
840 #endif /* VJC */
841 	break;
842 
843 #ifdef PPP_COMPRESS
844     case SIOCGPPPCSTATS:
845 	pcp = &((struct ifpppcstatsreq *) data)->stats;
846 	memset(pcp, 0, sizeof(*pcp));
847 	if (sc->sc_xc_state != NULL)
848 	    (*sc->sc_xcomp->comp_stat)(sc->sc_xc_state, &pcp->c);
849 	if (sc->sc_rc_state != NULL)
850 	    (*sc->sc_rcomp->decomp_stat)(sc->sc_rc_state, &pcp->d);
851 	break;
852 #endif /* PPP_COMPRESS */
853 
854     default:
855 	error = EINVAL;
856     }
857     splx(s);
858     return (error);
859 }
860 
861 /*
862  * Queue a packet.  Start transmission if not active.
863  * Packet is placed in Information field of PPP frame.
864  */
865 int
866 pppoutput(struct ifnet *ifp, struct mbuf *m0, struct sockaddr *dst,
867           struct rtentry *rtp)
868 {
869     struct ppp_softc *sc = ifp->if_softc;
870     int protocol, address, control;
871     u_char *cp;
872     int s, error;
873 #ifdef INET
874     struct ip *ip;
875 #endif
876     struct ifqueue *ifq;
877     enum NPmode mode;
878     int len;
879     ALTQ_DECL(struct altq_pktattr pktattr;)
880 
881     if (sc->sc_devp == NULL || (ifp->if_flags & IFF_RUNNING) == 0
882 	|| ((ifp->if_flags & IFF_UP) == 0 && dst->sa_family != AF_UNSPEC)) {
883 	error = ENETDOWN;	/* sort of */
884 	goto bad;
885     }
886 
887     IFQ_CLASSIFY(&ifp->if_snd, m0, dst->sa_family, &pktattr);
888 
889     /*
890      * Compute PPP header.
891      */
892     m0->m_flags &= ~M_HIGHPRI;
893     switch (dst->sa_family) {
894 #ifdef INET
895     case AF_INET:
896 	address = PPP_ALLSTATIONS;
897 	control = PPP_UI;
898 	protocol = PPP_IP;
899 	mode = sc->sc_npmode[NP_IP];
900 
901 	/*
902 	 * If this packet has the "low delay" bit set in the IP header,
903 	 * put it on the fastq instead.
904 	 */
905 	ip = mtod(m0, struct ip *);
906 	if (ip->ip_tos & IPTOS_LOWDELAY)
907 	    m0->m_flags |= M_HIGHPRI;
908 	break;
909 #endif
910 #ifdef INET6
911     case AF_INET6:
912 	address = PPP_ALLSTATIONS;	/*XXX*/
913 	control = PPP_UI;		/*XXX*/
914 	protocol = PPP_IPV6;
915 	mode = sc->sc_npmode[NP_IPV6];
916 
917 #if 0	/* XXX flowinfo/traffic class, maybe? */
918 	/*
919 	 * If this packet has the "low delay" bit set in the IP header,
920 	 * put it on the fastq instead.
921 	 */
922 	ip = mtod(m0, struct ip *);
923 	if (ip->ip_tos & IPTOS_LOWDELAY)
924 	    m0->m_flags |= M_HIGHPRI;
925 #endif
926 	break;
927 #endif
928     case AF_UNSPEC:
929 	address = PPP_ADDRESS(dst->sa_data);
930 	control = PPP_CONTROL(dst->sa_data);
931 	protocol = PPP_PROTOCOL(dst->sa_data);
932 	mode = NPMODE_PASS;
933 	break;
934     default:
935 	printf("%s: af%d not supported\n", ifp->if_xname, dst->sa_family);
936 	error = EAFNOSUPPORT;
937 	goto bad;
938     }
939 
940     /*
941      * Drop this packet, or return an error, if necessary.
942      */
943     if (mode == NPMODE_ERROR) {
944 	error = ENETDOWN;
945 	goto bad;
946     }
947     if (mode == NPMODE_DROP) {
948 	error = 0;
949 	goto bad;
950     }
951 
952     /*
953      * Add PPP header.
954      */
955     M_PREPEND(m0, PPP_HDRLEN, M_DONTWAIT);
956     if (m0 == NULL) {
957 	error = ENOBUFS;
958 	goto bad;
959     }
960 
961     cp = mtod(m0, u_char *);
962     *cp++ = address;
963     *cp++ = control;
964     *cp++ = protocol >> 8;
965     *cp++ = protocol & 0xff;
966 
967     len = m_length(m0);
968 
969     if (sc->sc_flags & SC_LOG_OUTPKT) {
970 	printf("%s output: ", ifp->if_xname);
971 	pppdumpm(m0);
972     }
973 
974     if ((protocol & 0x8000) == 0) {
975 #ifdef PPP_FILTER
976 	/*
977 	 * Apply the pass and active filters to the packet,
978 	 * but only if it is a data packet.
979 	 */
980 	if (sc->sc_pass_filt_out.bf_insns != 0
981 	    && bpf_filter(sc->sc_pass_filt_out.bf_insns, (u_char *) m0,
982 			  len, 0) == 0) {
983 	    error = 0;		/* drop this packet */
984 	    goto bad;
985 	}
986 
987 	/*
988 	 * Update the time we sent the most recent packet.
989 	 */
990 	if (sc->sc_active_filt_out.bf_insns == 0
991 	    || bpf_filter(sc->sc_active_filt_out.bf_insns, (u_char *) m0,
992 	    		  len, 0))
993 	    sc->sc_last_sent = time.tv_sec;
994 #else
995 	/*
996 	 * Update the time we sent the most recent packet.
997 	 */
998 	sc->sc_last_sent = time.tv_sec;
999 #endif /* PPP_FILTER */
1000     }
1001 
1002 #if NBPFILTER > 0
1003     /*
1004      * See if bpf wants to look at the packet.
1005      */
1006     if (sc->sc_if.if_bpf)
1007 	bpf_mtap(sc->sc_if.if_bpf, m0);
1008 #endif
1009 
1010     /*
1011      * Put the packet on the appropriate queue.
1012      */
1013     s = splnet();
1014     if (mode == NPMODE_QUEUE) {
1015 	/* XXX we should limit the number of packets on this queue */
1016 	*sc->sc_npqtail = m0;
1017 	m0->m_nextpkt = NULL;
1018 	sc->sc_npqtail = &m0->m_nextpkt;
1019     } else {
1020 	ifq = (m0->m_flags & M_HIGHPRI) ? &sc->sc_fastq : NULL;
1021 	if ((error = ifq_enqueue2(&sc->sc_if, ifq, m0
1022 		ALTQ_COMMA ALTQ_DECL(&pktattr))) != 0) {
1023 	    splx(s);
1024 	    sc->sc_if.if_oerrors++;
1025 	    sc->sc_stats.ppp_oerrors++;
1026 	    return (error);
1027 	}
1028 	ppp_restart(sc);
1029     }
1030     ifp->if_opackets++;
1031     ifp->if_obytes += len;
1032 
1033     splx(s);
1034     return (0);
1035 
1036 bad:
1037     m_freem(m0);
1038     return (error);
1039 }
1040 
1041 /*
1042  * After a change in the NPmode for some NP, move packets from the
1043  * npqueue to the send queue or the fast queue as appropriate.
1044  * Should be called at splnet, since we muck with the queues.
1045  */
1046 static void
1047 ppp_requeue(struct ppp_softc *sc)
1048 {
1049     struct mbuf *m, **mpp;
1050     struct ifqueue *ifq;
1051     enum NPmode mode;
1052     int error;
1053 
1054     for (mpp = &sc->sc_npqueue; (m = *mpp) != NULL; ) {
1055 	switch (PPP_PROTOCOL(mtod(m, u_char *))) {
1056 	case PPP_IP:
1057 	    mode = sc->sc_npmode[NP_IP];
1058 	    break;
1059 	case PPP_IPV6:
1060 	    mode = sc->sc_npmode[NP_IPV6];
1061 	    break;
1062 	default:
1063 	    mode = NPMODE_PASS;
1064 	}
1065 
1066 	switch (mode) {
1067 	case NPMODE_PASS:
1068 	    /*
1069 	     * This packet can now go on one of the queues to be sent.
1070 	     */
1071 	    *mpp = m->m_nextpkt;
1072 	    m->m_nextpkt = NULL;
1073 	    ifq = (m->m_flags & M_HIGHPRI) ? &sc->sc_fastq : NULL;
1074 	    if ((error = ifq_enqueue2(&sc->sc_if, ifq, m ALTQ_COMMA
1075 		ALTQ_DECL(NULL))) != 0) {
1076 		sc->sc_if.if_oerrors++;
1077 		sc->sc_stats.ppp_oerrors++;
1078 	    }
1079 	    break;
1080 
1081 	case NPMODE_DROP:
1082 	case NPMODE_ERROR:
1083 	    *mpp = m->m_nextpkt;
1084 	    m_freem(m);
1085 	    break;
1086 
1087 	case NPMODE_QUEUE:
1088 	    mpp = &m->m_nextpkt;
1089 	    break;
1090 	}
1091     }
1092     sc->sc_npqtail = mpp;
1093 }
1094 
1095 /*
1096  * Transmitter has finished outputting some stuff;
1097  * remember to call sc->sc_start later at splsoftnet.
1098  */
1099 void
1100 ppp_restart(struct ppp_softc *sc)
1101 {
1102     int s = splhigh();	/* XXX IMP ME HARDER */
1103 
1104     sc->sc_flags &= ~SC_TBUSY;
1105 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
1106     softintr_schedule(sc->sc_si);
1107 #else
1108     schednetisr(NETISR_PPP);
1109 #endif
1110     splx(s);
1111 }
1112 
1113 /*
1114  * Get a packet to send.  This procedure is intended to be called at
1115  * splsoftnet, since it may involve time-consuming operations such as
1116  * applying VJ compression, packet compression, address/control and/or
1117  * protocol field compression to the packet.
1118  */
1119 struct mbuf *
1120 ppp_dequeue(struct ppp_softc *sc)
1121 {
1122     struct mbuf *m, *mp;
1123     u_char *cp;
1124     int address, control, protocol;
1125     int s;
1126 
1127     /*
1128      * Grab a packet to send: first try the fast queue, then the
1129      * normal queue.
1130      */
1131     s = splnet();
1132     IF_DEQUEUE(&sc->sc_fastq, m);
1133     if (m == NULL)
1134 	IFQ_DEQUEUE(&sc->sc_if.if_snd, m);
1135     splx(s);
1136 
1137     if (m == NULL)
1138 	return NULL;
1139 
1140     ++sc->sc_stats.ppp_opackets;
1141 
1142     /*
1143      * Extract the ppp header of the new packet.
1144      * The ppp header will be in one mbuf.
1145      */
1146     cp = mtod(m, u_char *);
1147     address = PPP_ADDRESS(cp);
1148     control = PPP_CONTROL(cp);
1149     protocol = PPP_PROTOCOL(cp);
1150 
1151     switch (protocol) {
1152     case PPP_IP:
1153 #ifdef VJC
1154 	/*
1155 	 * If the packet is a TCP/IP packet, see if we can compress it.
1156 	 */
1157 	if ((sc->sc_flags & SC_COMP_TCP) && sc->sc_comp != NULL) {
1158 	    struct ip *ip;
1159 	    int type;
1160 
1161 	    mp = m;
1162 	    ip = (struct ip *) (cp + PPP_HDRLEN);
1163 	    if (mp->m_len <= PPP_HDRLEN) {
1164 		mp = mp->m_next;
1165 		if (mp == NULL)
1166 		    break;
1167 		ip = mtod(mp, struct ip *);
1168 	    }
1169 	    /* this code assumes the IP/TCP header is in one non-shared mbuf */
1170 	    if (ip->ip_p == IPPROTO_TCP) {
1171 		type = sl_compress_tcp(mp, ip, sc->sc_comp,
1172 				       !(sc->sc_flags & SC_NO_TCP_CCID));
1173 		switch (type) {
1174 		case TYPE_UNCOMPRESSED_TCP:
1175 		    protocol = PPP_VJC_UNCOMP;
1176 		    break;
1177 		case TYPE_COMPRESSED_TCP:
1178 		    protocol = PPP_VJC_COMP;
1179 		    cp = mtod(m, u_char *);
1180 		    cp[0] = address;	/* header has moved */
1181 		    cp[1] = control;
1182 		    cp[2] = 0;
1183 		    break;
1184 		}
1185 		cp[3] = protocol;	/* update protocol in PPP header */
1186 	    }
1187 	}
1188 #endif	/* VJC */
1189 	break;
1190 
1191 #ifdef PPP_COMPRESS
1192     case PPP_CCP:
1193 	ppp_ccp(sc, m, 0);
1194 	break;
1195 #endif	/* PPP_COMPRESS */
1196     }
1197 
1198 #ifdef PPP_COMPRESS
1199     if (protocol != PPP_LCP && protocol != PPP_CCP
1200 	&& sc->sc_xc_state && (sc->sc_flags & SC_COMP_RUN)) {
1201 	struct mbuf *mcomp = NULL;
1202 	int slen;
1203 
1204 	slen = 0;
1205 	for (mp = m; mp != NULL; mp = mp->m_next)
1206 	    slen += mp->m_len;
1207 	(*sc->sc_xcomp->compress)
1208 	    (sc->sc_xc_state, &mcomp, m, slen, sc->sc_if.if_mtu + PPP_HDRLEN);
1209 	if (mcomp != NULL) {
1210 	    if (sc->sc_flags & SC_CCP_UP) {
1211 		/* Send the compressed packet instead of the original. */
1212 		m_freem(m);
1213 		m = mcomp;
1214 		cp = mtod(m, u_char *);
1215 		protocol = cp[3];
1216 	    } else {
1217 		/* Can't transmit compressed packets until CCP is up. */
1218 		m_freem(mcomp);
1219 	    }
1220 	}
1221     }
1222 #endif	/* PPP_COMPRESS */
1223 
1224     /*
1225      * Compress the address/control and protocol, if possible.
1226      */
1227     if (sc->sc_flags & SC_COMP_AC && address == PPP_ALLSTATIONS &&
1228 	control == PPP_UI && protocol != PPP_ALLSTATIONS &&
1229 	protocol != PPP_LCP) {
1230 	/* can compress address/control */
1231 	m->m_data += 2;
1232 	m->m_len -= 2;
1233     }
1234     if (sc->sc_flags & SC_COMP_PROT && protocol < 0xFF) {
1235 	/* can compress protocol */
1236 	if (mtod(m, u_char *) == cp) {
1237 	    cp[2] = cp[1];	/* move address/control up */
1238 	    cp[1] = cp[0];
1239 	}
1240 	++m->m_data;
1241 	--m->m_len;
1242     }
1243 
1244     return m;
1245 }
1246 
1247 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS
1248 void
1249 pppnetisr(void)
1250 {
1251 	struct ppp_softc *sc;
1252 
1253 	for (sc = LIST_FIRST(&ppp_softc_list); sc != NULL;
1254 	    sc = LIST_NEXT(sc, sc_iflist))
1255 		pppintr(sc);
1256 }
1257 #endif
1258 
1259 /*
1260  * Software interrupt routine, called at splsoftnet.
1261  */
1262 static void
1263 pppintr(void *arg)
1264 {
1265 	struct ppp_softc *sc = arg;
1266 	struct mbuf *m;
1267 	int s;
1268 
1269 	if (!(sc->sc_flags & SC_TBUSY)
1270 	    && (IFQ_IS_EMPTY(&sc->sc_if.if_snd) == 0 || sc->sc_fastq.ifq_head
1271 		|| sc->sc_outm)) {
1272 		s = splhigh();	/* XXX IMP ME HARDER */
1273 		sc->sc_flags |= SC_TBUSY;
1274 		splx(s);
1275 		(*sc->sc_start)(sc);
1276 	}
1277 	for (;;) {
1278 		s = splnet();
1279 		IF_DEQUEUE(&sc->sc_rawq, m);
1280 		splx(s);
1281 		if (m == NULL)
1282 			break;
1283 		ppp_inproc(sc, m);
1284 	}
1285 }
1286 
1287 #ifdef PPP_COMPRESS
1288 /*
1289  * Handle a CCP packet.  `rcvd' is 1 if the packet was received,
1290  * 0 if it is about to be transmitted.
1291  */
1292 static void
1293 ppp_ccp(struct ppp_softc *sc, struct mbuf *m, int rcvd)
1294 {
1295     u_char *dp, *ep;
1296     struct mbuf *mp;
1297     int slen, s;
1298 
1299     /*
1300      * Get a pointer to the data after the PPP header.
1301      */
1302     if (m->m_len <= PPP_HDRLEN) {
1303 	mp = m->m_next;
1304 	if (mp == NULL)
1305 	    return;
1306 	dp = (mp != NULL)? mtod(mp, u_char *): NULL;
1307     } else {
1308 	mp = m;
1309 	dp = mtod(mp, u_char *) + PPP_HDRLEN;
1310     }
1311 
1312     ep = mtod(mp, u_char *) + mp->m_len;
1313     if (dp + CCP_HDRLEN > ep)
1314 	return;
1315     slen = CCP_LENGTH(dp);
1316     if (dp + slen > ep) {
1317 	if (sc->sc_flags & SC_DEBUG)
1318 	    printf("if_ppp/ccp: not enough data in mbuf (%p+%x > %p+%x)\n",
1319 		dp, slen, mtod(mp, u_char *), mp->m_len);
1320 	return;
1321     }
1322 
1323     switch (CCP_CODE(dp)) {
1324     case CCP_CONFREQ:
1325     case CCP_TERMREQ:
1326     case CCP_TERMACK:
1327 	/* CCP must be going down - disable compression */
1328 	if (sc->sc_flags & SC_CCP_UP) {
1329 	    s = splhigh();	/* XXX IMP ME HARDER */
1330 	    sc->sc_flags &= ~(SC_CCP_UP | SC_COMP_RUN | SC_DECOMP_RUN);
1331 	    splx(s);
1332 	}
1333 	break;
1334 
1335     case CCP_CONFACK:
1336 	if (sc->sc_flags & SC_CCP_OPEN && !(sc->sc_flags & SC_CCP_UP)
1337 	    && slen >= CCP_HDRLEN + CCP_OPT_MINLEN
1338 	    && slen >= CCP_OPT_LENGTH(dp + CCP_HDRLEN) + CCP_HDRLEN) {
1339 	    if (!rcvd) {
1340 		/* we're agreeing to send compressed packets. */
1341 		if (sc->sc_xc_state != NULL
1342 		    && (*sc->sc_xcomp->comp_init)
1343 			(sc->sc_xc_state, dp + CCP_HDRLEN, slen - CCP_HDRLEN,
1344 			 sc->sc_unit, 0, sc->sc_flags & SC_DEBUG)) {
1345 		    s = splhigh();	/* XXX IMP ME HARDER */
1346 		    sc->sc_flags |= SC_COMP_RUN;
1347 		    splx(s);
1348 		}
1349 	    } else {
1350 		/* peer is agreeing to send compressed packets. */
1351 		if (sc->sc_rc_state != NULL
1352 		    && (*sc->sc_rcomp->decomp_init)
1353 			(sc->sc_rc_state, dp + CCP_HDRLEN, slen - CCP_HDRLEN,
1354 			 sc->sc_unit, 0, sc->sc_mru,
1355 			 sc->sc_flags & SC_DEBUG)) {
1356 		    s = splhigh();	/* XXX IMP ME HARDER */
1357 		    sc->sc_flags |= SC_DECOMP_RUN;
1358 		    sc->sc_flags &= ~(SC_DC_ERROR | SC_DC_FERROR);
1359 		    splx(s);
1360 		}
1361 	    }
1362 	}
1363 	break;
1364 
1365     case CCP_RESETACK:
1366 	if (sc->sc_flags & SC_CCP_UP) {
1367 	    if (!rcvd) {
1368 		if (sc->sc_xc_state && (sc->sc_flags & SC_COMP_RUN))
1369 		    (*sc->sc_xcomp->comp_reset)(sc->sc_xc_state);
1370 	    } else {
1371 		if (sc->sc_rc_state && (sc->sc_flags & SC_DECOMP_RUN)) {
1372 		    (*sc->sc_rcomp->decomp_reset)(sc->sc_rc_state);
1373 		    s = splhigh();	/* XXX IMP ME HARDER */
1374 		    sc->sc_flags &= ~SC_DC_ERROR;
1375 		    splx(s);
1376 		}
1377 	    }
1378 	}
1379 	break;
1380     }
1381 }
1382 
1383 /*
1384  * CCP is down; free (de)compressor state if necessary.
1385  */
1386 static void
1387 ppp_ccp_closed(struct ppp_softc *sc)
1388 {
1389     if (sc->sc_xc_state) {
1390 	(*sc->sc_xcomp->comp_free)(sc->sc_xc_state);
1391 	sc->sc_xc_state = NULL;
1392     }
1393     if (sc->sc_rc_state) {
1394 	(*sc->sc_rcomp->decomp_free)(sc->sc_rc_state);
1395 	sc->sc_rc_state = NULL;
1396     }
1397 }
1398 #endif /* PPP_COMPRESS */
1399 
1400 /*
1401  * PPP packet input routine.
1402  * The caller has checked and removed the FCS and has inserted
1403  * the address/control bytes and the protocol high byte if they
1404  * were omitted.
1405  */
1406 void
1407 ppppktin(struct ppp_softc *sc, struct mbuf *m, int lost)
1408 {
1409     int s = splhigh();	/* XXX IMP ME HARDER */
1410 
1411     if (lost)
1412 	m->m_flags |= M_ERRMARK;
1413     IF_ENQUEUE(&sc->sc_rawq, m);
1414 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
1415     softintr_schedule(sc->sc_si);
1416 #else
1417     schednetisr(NETISR_PPP);
1418 #endif
1419     splx(s);
1420 }
1421 
1422 /*
1423  * Process a received PPP packet, doing decompression as necessary.
1424  * Should be called at splsoftnet.
1425  */
1426 #define COMPTYPE(proto)	((proto) == PPP_VJC_COMP? TYPE_COMPRESSED_TCP: \
1427 			 TYPE_UNCOMPRESSED_TCP)
1428 
1429 static void
1430 ppp_inproc(struct ppp_softc *sc, struct mbuf *m)
1431 {
1432     struct ifnet *ifp = &sc->sc_if;
1433     struct ifqueue *inq;
1434     int s, ilen, proto, rv;
1435     u_char *cp, adrs, ctrl;
1436     struct mbuf *mp, *dmp = NULL;
1437 #ifdef VJC
1438     int xlen;
1439     u_char *iphdr;
1440     u_int hlen;
1441 #endif
1442 
1443     sc->sc_stats.ppp_ipackets++;
1444 
1445     if (sc->sc_flags & SC_LOG_INPKT) {
1446 	ilen = 0;
1447 	for (mp = m; mp != NULL; mp = mp->m_next)
1448 	    ilen += mp->m_len;
1449 	printf("%s: got %d bytes\n", ifp->if_xname, ilen);
1450 	pppdumpm(m);
1451     }
1452 
1453     cp = mtod(m, u_char *);
1454     adrs = PPP_ADDRESS(cp);
1455     ctrl = PPP_CONTROL(cp);
1456     proto = PPP_PROTOCOL(cp);
1457 
1458     if (m->m_flags & M_ERRMARK) {
1459 	m->m_flags &= ~M_ERRMARK;
1460 	s = splhigh();	/* XXX IMP ME HARDER */
1461 	sc->sc_flags |= SC_VJ_RESET;
1462 	splx(s);
1463     }
1464 
1465 #ifdef PPP_COMPRESS
1466     /*
1467      * Decompress this packet if necessary, update the receiver's
1468      * dictionary, or take appropriate action on a CCP packet.
1469      */
1470     if (proto == PPP_COMP && sc->sc_rc_state && (sc->sc_flags & SC_DECOMP_RUN)
1471 	&& !(sc->sc_flags & SC_DC_ERROR) && !(sc->sc_flags & SC_DC_FERROR)) {
1472 	/* decompress this packet */
1473 	rv = (*sc->sc_rcomp->decompress)(sc->sc_rc_state, m, &dmp);
1474 	if (rv == DECOMP_OK) {
1475 	    m_freem(m);
1476 	    if (dmp == NULL) {
1477 		/* no error, but no decompressed packet produced */
1478 		return;
1479 	    }
1480 	    m = dmp;
1481 	    cp = mtod(m, u_char *);
1482 	    proto = PPP_PROTOCOL(cp);
1483 
1484 	} else {
1485 	    /*
1486 	     * An error has occurred in decompression.
1487 	     * Pass the compressed packet up to pppd, which may take
1488 	     * CCP down or issue a Reset-Req.
1489 	     */
1490 	    if (sc->sc_flags & SC_DEBUG)
1491 		printf("%s: decompress failed %d\n", ifp->if_xname, rv);
1492 	    s = splhigh();	/* XXX IMP ME HARDER */
1493 	    sc->sc_flags |= SC_VJ_RESET;
1494 	    if (rv == DECOMP_ERROR)
1495 		sc->sc_flags |= SC_DC_ERROR;
1496 	    else
1497 		sc->sc_flags |= SC_DC_FERROR;
1498 	    splx(s);
1499 	}
1500 
1501     } else {
1502 	if (sc->sc_rc_state && (sc->sc_flags & SC_DECOMP_RUN)) {
1503 	    (*sc->sc_rcomp->incomp)(sc->sc_rc_state, m);
1504 	}
1505 	if (proto == PPP_CCP) {
1506 	    ppp_ccp(sc, m, 1);
1507 	}
1508     }
1509 #endif
1510 
1511     ilen = 0;
1512     for (mp = m; mp != NULL; mp = mp->m_next)
1513 	ilen += mp->m_len;
1514 
1515 #ifdef VJC
1516     if (sc->sc_flags & SC_VJ_RESET) {
1517 	/*
1518 	 * If we've missed a packet, we must toss subsequent compressed
1519 	 * packets which don't have an explicit connection ID.
1520 	 */
1521 	if (sc->sc_comp)
1522 	    sl_uncompress_tcp(NULL, 0, TYPE_ERROR, sc->sc_comp);
1523 	s = splhigh();	/* XXX IMP ME HARDER */
1524 	sc->sc_flags &= ~SC_VJ_RESET;
1525 	splx(s);
1526     }
1527 
1528     /*
1529      * See if we have a VJ-compressed packet to uncompress.
1530      */
1531     if (proto == PPP_VJC_COMP) {
1532 	if ((sc->sc_flags & SC_REJ_COMP_TCP) || sc->sc_comp == 0)
1533 	    goto bad;
1534 
1535 	xlen = sl_uncompress_tcp_core(cp + PPP_HDRLEN, m->m_len - PPP_HDRLEN,
1536 				      ilen - PPP_HDRLEN, TYPE_COMPRESSED_TCP,
1537 				      sc->sc_comp, &iphdr, &hlen);
1538 
1539 	if (xlen <= 0) {
1540 	    if (sc->sc_flags & SC_DEBUG)
1541 		printf("%s: VJ uncompress failed on type comp\n",
1542 		    ifp->if_xname);
1543 	    goto bad;
1544 	}
1545 
1546 	/* Copy the PPP and IP headers into a new mbuf. */
1547 	MGETHDR(mp, M_DONTWAIT, MT_DATA);
1548 	if (mp == NULL)
1549 	    goto bad;
1550 	mp->m_len = 0;
1551 	mp->m_next = NULL;
1552 	if (hlen + PPP_HDRLEN > MHLEN) {
1553 	    MCLGET(mp, M_DONTWAIT);
1554 	    if (M_TRAILINGSPACE(mp) < hlen + PPP_HDRLEN) {
1555 		m_freem(mp);
1556 		goto bad;	/* lose if big headers and no clusters */
1557 	    }
1558 	}
1559 	cp = mtod(mp, u_char *);
1560 	cp[0] = adrs;
1561 	cp[1] = ctrl;
1562 	cp[2] = 0;
1563 	cp[3] = PPP_IP;
1564 	proto = PPP_IP;
1565 	bcopy(iphdr, cp + PPP_HDRLEN, hlen);
1566 	mp->m_len = hlen + PPP_HDRLEN;
1567 
1568 	/*
1569 	 * Trim the PPP and VJ headers off the old mbuf
1570 	 * and stick the new and old mbufs together.
1571 	 */
1572 	m->m_data += PPP_HDRLEN + xlen;
1573 	m->m_len -= PPP_HDRLEN + xlen;
1574 	if (m->m_len <= M_TRAILINGSPACE(mp)) {
1575 	    bcopy(mtod(m, u_char *), mtod(mp, u_char *) + mp->m_len, m->m_len);
1576 	    mp->m_len += m->m_len;
1577 	    MFREE(m, mp->m_next);
1578 	} else
1579 	    mp->m_next = m;
1580 	m = mp;
1581 	ilen += hlen - xlen;
1582 
1583     } else if (proto == PPP_VJC_UNCOMP) {
1584 	if ((sc->sc_flags & SC_REJ_COMP_TCP) || sc->sc_comp == 0)
1585 	    goto bad;
1586 
1587 	xlen = sl_uncompress_tcp_core(cp + PPP_HDRLEN, m->m_len - PPP_HDRLEN,
1588 				      ilen - PPP_HDRLEN, TYPE_UNCOMPRESSED_TCP,
1589 				      sc->sc_comp, &iphdr, &hlen);
1590 
1591 	if (xlen < 0) {
1592 	    if (sc->sc_flags & SC_DEBUG)
1593 		printf("%s: VJ uncompress failed on type uncomp\n",
1594 		    ifp->if_xname);
1595 	    goto bad;
1596 	}
1597 
1598 	proto = PPP_IP;
1599 	cp[3] = PPP_IP;
1600     }
1601 #endif /* VJC */
1602 
1603     /*
1604      * If the packet will fit in a header mbuf, don't waste a
1605      * whole cluster on it.
1606      */
1607     if (ilen <= MHLEN && M_IS_CLUSTER(m)) {
1608 	MGETHDR(mp, M_DONTWAIT, MT_DATA);
1609 	if (mp != NULL) {
1610 	    m_copydata(m, 0, ilen, mtod(mp, caddr_t));
1611 	    m_freem(m);
1612 	    m = mp;
1613 	    m->m_len = ilen;
1614 	}
1615     }
1616     m->m_pkthdr.len = ilen;
1617     m->m_pkthdr.rcvif = ifp;
1618 
1619     if ((proto & 0x8000) == 0) {
1620 #ifdef PPP_FILTER
1621 	/*
1622 	 * See whether we want to pass this packet, and
1623 	 * if it counts as link activity.
1624 	 */
1625 	if (sc->sc_pass_filt_in.bf_insns != 0
1626 	    && bpf_filter(sc->sc_pass_filt_in.bf_insns, (u_char *) m,
1627 			  ilen, 0) == 0) {
1628 	    /* drop this packet */
1629 	    m_freem(m);
1630 	    return;
1631 	}
1632 	if (sc->sc_active_filt_in.bf_insns == 0
1633 	    || bpf_filter(sc->sc_active_filt_in.bf_insns, (u_char *) m,
1634 	    		  ilen, 0))
1635 	    sc->sc_last_recv = time.tv_sec;
1636 #else
1637 	/*
1638 	 * Record the time that we received this packet.
1639 	 */
1640 	sc->sc_last_recv = time.tv_sec;
1641 #endif /* PPP_FILTER */
1642     }
1643 
1644 #if NBPFILTER > 0
1645     /* See if bpf wants to look at the packet. */
1646     if (sc->sc_if.if_bpf)
1647 	bpf_mtap(sc->sc_if.if_bpf, m);
1648 #endif
1649 
1650     rv = 0;
1651     switch (proto) {
1652 #ifdef INET
1653     case PPP_IP:
1654 	/*
1655 	 * IP packet - take off the ppp header and pass it up to IP.
1656 	 */
1657 	if ((ifp->if_flags & IFF_UP) == 0
1658 	    || sc->sc_npmode[NP_IP] != NPMODE_PASS) {
1659 	    /* interface is down - drop the packet. */
1660 	    m_freem(m);
1661 	    return;
1662 	}
1663 	m->m_pkthdr.len -= PPP_HDRLEN;
1664 	m->m_data += PPP_HDRLEN;
1665 	m->m_len -= PPP_HDRLEN;
1666 #ifdef GATEWAY
1667 	if (ipflow_fastforward(m))
1668 		return;
1669 #endif
1670 	schednetisr(NETISR_IP);
1671 	inq = &ipintrq;
1672 	break;
1673 #endif
1674 
1675 #ifdef INET6
1676     case PPP_IPV6:
1677 	/*
1678 	 * IPv6 packet - take off the ppp header and pass it up to IPv6.
1679 	 */
1680 	if ((ifp->if_flags & IFF_UP) == 0
1681 	    || sc->sc_npmode[NP_IPV6] != NPMODE_PASS) {
1682 	    /* interface is down - drop the packet. */
1683 	    m_freem(m);
1684 	    return;
1685 	}
1686 	m->m_pkthdr.len -= PPP_HDRLEN;
1687 	m->m_data += PPP_HDRLEN;
1688 	m->m_len -= PPP_HDRLEN;
1689 	schednetisr(NETISR_IPV6);
1690 	inq = &ip6intrq;
1691 	break;
1692 #endif
1693 
1694     default:
1695 	/*
1696 	 * Some other protocol - place on input queue for read().
1697 	 */
1698 	inq = &sc->sc_inq;
1699 	rv = 1;
1700 	break;
1701     }
1702 
1703     /*
1704      * Put the packet on the appropriate input queue.
1705      */
1706     s = splnet();
1707     if (IF_QFULL(inq)) {
1708 	IF_DROP(inq);
1709 	splx(s);
1710 	if (sc->sc_flags & SC_DEBUG)
1711 	    printf("%s: input queue full\n", ifp->if_xname);
1712 	ifp->if_iqdrops++;
1713 	goto bad;
1714     }
1715     IF_ENQUEUE(inq, m);
1716     splx(s);
1717     ifp->if_ipackets++;
1718     ifp->if_ibytes += ilen;
1719 
1720     if (rv)
1721 	(*sc->sc_ctlp)(sc);
1722 
1723     return;
1724 
1725  bad:
1726     m_freem(m);
1727     sc->sc_if.if_ierrors++;
1728     sc->sc_stats.ppp_ierrors++;
1729 }
1730 
1731 #define MAX_DUMP_BYTES	128
1732 
1733 static void
1734 pppdumpm(struct mbuf *m0)
1735 {
1736     char buf[3*MAX_DUMP_BYTES+4];
1737     char *bp = buf;
1738     struct mbuf *m;
1739 
1740     for (m = m0; m; m = m->m_next) {
1741 	int l = m->m_len;
1742 	u_char *rptr = (u_char *)m->m_data;
1743 
1744 	while (l--) {
1745 	    if (bp > buf + sizeof(buf) - 4)
1746 		goto done;
1747 	    *bp++ = hexdigits[*rptr >> 4]; /* convert byte to ascii hex */
1748 	    *bp++ = hexdigits[*rptr++ & 0xf];
1749 	}
1750 
1751 	if (m->m_next) {
1752 	    if (bp > buf + sizeof(buf) - 3)
1753 		goto done;
1754 	    *bp++ = '|';
1755 	} else
1756 	    *bp++ = ' ';
1757     }
1758 done:
1759     if (m)
1760 	*bp++ = '>';
1761     *bp = 0;
1762     printf("%s\n", buf);
1763 }
1764 
1765 #ifdef ALTQ
1766 /*
1767  * a wrapper to transmit a packet from if_start since ALTQ uses
1768  * if_start to send a packet.
1769  */
1770 static void
1771 ppp_ifstart(struct ifnet *ifp)
1772 {
1773 	struct ppp_softc *sc;
1774 
1775 	sc = ifp->if_softc;
1776 	(*sc->sc_start)(sc);
1777 }
1778 #endif
1779