if_sl.c revision 1.95.6.2 1 /* $NetBSD: if_sl.c,v 1.95.6.2 2006/04/22 11:40:06 simonb Exp $ */
2
3 /*
4 * Copyright (c) 1987, 1989, 1992, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * @(#)if_sl.c 8.9 (Berkeley) 1/9/95
32 */
33
34 /*
35 * Serial Line interface
36 *
37 * Rick Adams
38 * Center for Seismic Studies
39 * 1300 N 17th Street, Suite 1450
40 * Arlington, Virginia 22209
41 * (703)276-7900
42 * rick (at) seismo.ARPA
43 * seismo!rick
44 *
45 * Pounded on heavily by Chris Torek (chris (at) mimsy.umd.edu, umcp-cs!chris).
46 * N.B.: this belongs in netinet, not net, the way it stands now.
47 * Should have a link-layer type designation, but wouldn't be
48 * backwards-compatible.
49 *
50 * Converted to 4.3BSD Beta by Chris Torek.
51 * Other changes made at Berkeley, based in part on code by Kirk Smith.
52 * W. Jolitz added slip abort.
53 *
54 * Hacked almost beyond recognition by Van Jacobson (van (at) helios.ee.lbl.gov).
55 * Added priority queuing for "interactive" traffic; hooks for TCP
56 * header compression; ICMP filtering (at 2400 baud, some cretin
57 * pinging you can use up all your bandwidth). Made low clist behavior
58 * more robust and slightly less likely to hang serial line.
59 * Sped up a bunch of things.
60 */
61
62 #include <sys/cdefs.h>
63 __KERNEL_RCSID(0, "$NetBSD: if_sl.c,v 1.95.6.2 2006/04/22 11:40:06 simonb Exp $");
64
65 #include "opt_inet.h"
66 #include "bpfilter.h"
67
68 #include <sys/param.h>
69 #include <sys/proc.h>
70 #include <sys/malloc.h>
71 #include <sys/mbuf.h>
72 #include <sys/buf.h>
73 #include <sys/dkstat.h>
74 #include <sys/socket.h>
75 #include <sys/ioctl.h>
76 #include <sys/file.h>
77 #include <sys/conf.h>
78 #include <sys/tty.h>
79 #include <sys/kernel.h>
80 #if __NetBSD__
81 #include <sys/systm.h>
82 #endif
83
84 #include <machine/cpu.h>
85 #include <machine/intr.h>
86
87 #include <net/if.h>
88 #include <net/if_types.h>
89 #include <net/netisr.h>
90 #include <net/route.h>
91
92 #ifdef INET
93 #include <netinet/in.h>
94 #include <netinet/in_systm.h>
95 #include <netinet/in_var.h>
96 #include <netinet/ip.h>
97 #endif
98
99 #include <net/slcompress.h>
100 #include <net/if_slvar.h>
101 #include <net/slip.h>
102 #include <net/ppp_defs.h>
103 #include <net/if_ppp.h>
104
105 #if NBPFILTER > 0
106 #include <sys/time.h>
107 #include <net/bpf.h>
108 #endif
109
110 /*
111 * SLMAX is a hard limit on input packet size. To simplify the code
112 * and improve performance, we require that packets fit in an mbuf
113 * cluster, and if we get a compressed packet, there's enough extra
114 * room to expand the header into a max length tcp/ip header (128
115 * bytes). So, SLMAX can be at most
116 * MCLBYTES - 128
117 *
118 * SLMTU is a hard limit on output packet size. To insure good
119 * interactive response, SLMTU wants to be the smallest size that
120 * amortizes the header cost. (Remember that even with
121 * type-of-service queuing, we have to wait for any in-progress
122 * packet to finish. I.e., we wait, on the average, 1/2 * mtu /
123 * cps, where cps is the line speed in characters per second.
124 * E.g., 533ms wait for a 1024 byte MTU on a 9600 baud line. The
125 * average compressed header size is 6-8 bytes so any MTU > 90
126 * bytes will give us 90% of the line bandwidth. A 100ms wait is
127 * tolerable (500ms is not), so want an MTU around 296. (Since TCP
128 * will send 256 byte segments (to allow for 40 byte headers), the
129 * typical packet size on the wire will be around 260 bytes). In
130 * 4.3tahoe+ systems, we can set an MTU in a route so we do that &
131 * leave the interface MTU relatively high (so we don't IP fragment
132 * when acting as a gateway to someone using a stupid MTU).
133 *
134 * Similar considerations apply to SLIP_HIWAT: It's the amount of
135 * data that will be queued 'downstream' of us (i.e., in clists
136 * waiting to be picked up by the tty output interrupt). If we
137 * queue a lot of data downstream, it's immune to our t.o.s. queuing.
138 * E.g., if SLIP_HIWAT is 1024, the interactive traffic in mixed
139 * telnet/ftp will see a 1 sec wait, independent of the mtu (the
140 * wait is dependent on the ftp window size but that's typically
141 * 1k - 4k). So, we want SLIP_HIWAT just big enough to amortize
142 * the cost (in idle time on the wire) of the tty driver running
143 * off the end of its clists & having to call back slstart for a
144 * new packet. For a tty interface with any buffering at all, this
145 * cost will be zero. Even with a totally brain dead interface (like
146 * the one on a typical workstation), the cost will be <= 1 character
147 * time. So, setting SLIP_HIWAT to ~100 guarantees that we'll lose
148 * at most 1% while maintaining good interactive response.
149 */
150 #define BUFOFFSET (128+sizeof(struct ifnet **)+SLIP_HDRLEN)
151 #define SLMAX (MCLBYTES - BUFOFFSET)
152 #define SLBUFSIZE (SLMAX + BUFOFFSET)
153 #ifndef SLMTU
154 #define SLMTU 296
155 #endif
156 #if (SLMTU < 3)
157 #error SLMTU way too small.
158 #endif
159 #define SLIP_HIWAT roundup(50,CBSIZE)
160 #ifndef __NetBSD__ /* XXX - cgd */
161 #define CLISTRESERVE 1024 /* Can't let clists get too low */
162 #endif /* !__NetBSD__ */
163
164 /*
165 * SLIP ABORT ESCAPE MECHANISM:
166 * (inspired by HAYES modem escape arrangement)
167 * 1sec escape 1sec escape 1sec escape { 1sec escape 1sec escape }
168 * within window time signals a "soft" exit from slip mode by remote end
169 * if the IFF_DEBUG flag is on.
170 */
171 #define ABT_ESC '\033' /* can't be t_intr - distant host must know it*/
172 #define ABT_IDLE 1 /* in seconds - idle before an escape */
173 #define ABT_COUNT 3 /* count of escapes for abort */
174 #define ABT_WINDOW (ABT_COUNT*2+2) /* in seconds - time to count */
175
176 static int sl_clone_create(struct if_clone *, int);
177 static int sl_clone_destroy(struct ifnet *);
178
179 static LIST_HEAD(, sl_softc) sl_softc_list;
180
181 struct if_clone sl_cloner =
182 IF_CLONE_INITIALIZER("sl", sl_clone_create, sl_clone_destroy);
183
184 #define FRAME_END 0xc0 /* Frame End */
185 #define FRAME_ESCAPE 0xdb /* Frame Esc */
186 #define TRANS_FRAME_END 0xdc /* transposed frame end */
187 #define TRANS_FRAME_ESCAPE 0xdd /* transposed frame esc */
188
189 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS
190 void slnetisr(void);
191 #endif
192 static void slintr(void *);
193
194 static int slinit(struct sl_softc *);
195 static struct mbuf *sl_btom(struct sl_softc *, int);
196
197 static int slclose(struct tty *, int);
198 static int slinput(int, struct tty *);
199 static int slioctl(struct ifnet *, u_long, caddr_t);
200 static int slopen(dev_t, struct tty *);
201 static int sloutput(struct ifnet *, struct mbuf *, struct sockaddr *,
202 struct rtentry *);
203 static int slstart(struct tty *);
204 static int sltioctl(struct tty *, u_long, caddr_t, int, struct lwp *);
205
206 static struct linesw slip_disc = {
207 .l_name = "slip",
208 .l_open = slopen,
209 .l_close = slclose,
210 .l_read = ttyerrio,
211 .l_write = ttyerrio,
212 .l_ioctl = sltioctl,
213 .l_rint = slinput,
214 .l_start = slstart,
215 .l_modem = nullmodem,
216 .l_poll = ttyerrpoll
217 };
218
219 void slattach(void);
220
221 void
222 slattach(void)
223 {
224 if (ttyldisc_attach(&slip_disc) != 0)
225 panic("slattach");
226 LIST_INIT(&sl_softc_list);
227 if_clone_attach(&sl_cloner);
228 }
229
230 static int
231 sl_clone_create(struct if_clone *ifc, int unit)
232 {
233 struct sl_softc *sc;
234
235 MALLOC(sc, struct sl_softc *, sizeof(*sc), M_DEVBUF, M_WAIT|M_ZERO);
236 sc->sc_unit = unit;
237 (void)snprintf(sc->sc_if.if_xname, sizeof(sc->sc_if.if_xname),
238 "%s%d", ifc->ifc_name, unit);
239 sc->sc_if.if_softc = sc;
240 sc->sc_if.if_mtu = SLMTU;
241 sc->sc_if.if_flags = IFF_POINTOPOINT | SC_AUTOCOMP | IFF_MULTICAST;
242 sc->sc_if.if_type = IFT_SLIP;
243 sc->sc_if.if_ioctl = slioctl;
244 sc->sc_if.if_output = sloutput;
245 sc->sc_if.if_dlt = DLT_SLIP;
246 sc->sc_fastq.ifq_maxlen = 32;
247 IFQ_SET_READY(&sc->sc_if.if_snd);
248 if_attach(&sc->sc_if);
249 if_alloc_sadl(&sc->sc_if);
250 #if NBPFILTER > 0
251 bpfattach(&sc->sc_if, DLT_SLIP, SLIP_HDRLEN);
252 #endif
253 LIST_INSERT_HEAD(&sl_softc_list, sc, sc_iflist);
254 return 0;
255 }
256
257 static int
258 sl_clone_destroy(struct ifnet *ifp)
259 {
260 struct sl_softc *sc = (struct sl_softc *)ifp->if_softc;
261
262 if (sc->sc_ttyp != NULL)
263 return EBUSY; /* Not removing it */
264
265 LIST_REMOVE(sc, sc_iflist);
266
267 #if NBPFILTER > 0
268 bpfdetach(ifp);
269 #endif
270 if_detach(ifp);
271
272 FREE(sc, M_DEVBUF);
273 return 0;
274 }
275
276 static int
277 slinit(struct sl_softc *sc)
278 {
279
280 if (sc->sc_mbuf == NULL) {
281 sc->sc_mbuf = m_gethdr(M_WAIT, MT_DATA);
282 m_clget(sc->sc_mbuf, M_WAIT);
283 }
284 sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf +
285 sc->sc_mbuf->m_ext.ext_size;
286 sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf +
287 BUFOFFSET;
288
289 #ifdef INET
290 sl_compress_init(&sc->sc_comp);
291 #endif
292
293 return (1);
294 }
295
296 /*
297 * Line specific open routine.
298 * Attach the given tty to the first available sl unit.
299 */
300 /* ARGSUSED */
301 static int
302 slopen(dev_t dev, struct tty *tp)
303 {
304 struct proc *p = curproc; /* XXX */
305 struct sl_softc *sc;
306 int error;
307 int s;
308
309 if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
310 return (error);
311
312 if (tp->t_linesw == &slip_disc)
313 return (0);
314
315 LIST_FOREACH(sc, &sl_softc_list, sc_iflist)
316 if (sc->sc_ttyp == NULL) {
317 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
318 sc->sc_si = softintr_establish(IPL_SOFTNET,
319 slintr, sc);
320 if (sc->sc_si == NULL)
321 return (ENOMEM);
322 #endif
323 if (slinit(sc) == 0) {
324 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
325 softintr_disestablish(sc->sc_si);
326 #endif
327 return (ENOBUFS);
328 }
329 tp->t_sc = (caddr_t)sc;
330 sc->sc_ttyp = tp;
331 sc->sc_if.if_baudrate = tp->t_ospeed;
332 s = spltty();
333 tp->t_state |= TS_ISOPEN | TS_XCLUDE;
334 splx(s);
335 ttyflush(tp, FREAD | FWRITE);
336 #ifdef __NetBSD__
337 /*
338 * make sure tty output queue is large enough
339 * to hold a full-sized packet (including frame
340 * end, and a possible extra frame end). full-sized
341 * packet occupies a max of 2*SLMAX bytes (because
342 * of possible escapes), and add two on for frame
343 * ends.
344 */
345 s = spltty();
346 if (tp->t_outq.c_cn < 2*SLMAX+2) {
347 sc->sc_oldbufsize = tp->t_outq.c_cn;
348 sc->sc_oldbufquot = tp->t_outq.c_cq != 0;
349
350 clfree(&tp->t_outq);
351 error = clalloc(&tp->t_outq, 2*SLMAX+2, 0);
352 if (error) {
353 splx(s);
354 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
355 softintr_disestablish(sc->sc_si);
356 #endif
357 /*
358 * clalloc() might return -1 which
359 * is no good, so we need to return
360 * something else.
361 */
362 return (ENOMEM); /* XXX ?! */
363 }
364 } else
365 sc->sc_oldbufsize = sc->sc_oldbufquot = 0;
366 splx(s);
367 #endif /* __NetBSD__ */
368 return (0);
369 }
370 return (ENXIO);
371 }
372
373 /*
374 * Line specific close routine.
375 * Detach the tty from the sl unit.
376 */
377 static int
378 slclose(struct tty *tp, int flag)
379 {
380 struct sl_softc *sc;
381 int s;
382
383 ttywflush(tp);
384 sc = tp->t_sc;
385
386 if (sc != NULL) {
387 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
388 softintr_disestablish(sc->sc_si);
389 #endif
390 s = splnet();
391 if_down(&sc->sc_if);
392 IF_PURGE(&sc->sc_fastq);
393 splx(s);
394
395 s = spltty();
396 ttyldisc_release(tp->t_linesw);
397 tp->t_linesw = ttyldisc_default();
398 tp->t_state = 0;
399
400 sc->sc_ttyp = NULL;
401 tp->t_sc = NULL;
402
403 m_freem(sc->sc_mbuf);
404 sc->sc_mbuf = NULL;
405 sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL;
406 IF_PURGE(&sc->sc_inq);
407
408 /*
409 * If necessary, install a new outq buffer of the
410 * appropriate size.
411 */
412 if (sc->sc_oldbufsize != 0) {
413 clfree(&tp->t_outq);
414 clalloc(&tp->t_outq, sc->sc_oldbufsize,
415 sc->sc_oldbufquot);
416 }
417 splx(s);
418 }
419
420 return (0);
421 }
422
423 /*
424 * Line specific (tty) ioctl routine.
425 * Provide a way to get the sl unit number.
426 */
427 /* ARGSUSED */
428 static int
429 sltioctl(struct tty *tp, u_long cmd, caddr_t data, int flag, struct lwp *l)
430 {
431 struct sl_softc *sc = (struct sl_softc *)tp->t_sc;
432
433 switch (cmd) {
434 case SLIOCGUNIT:
435 *(int *)data = sc->sc_unit; /* XXX */
436 break;
437
438 default:
439 return (EPASSTHROUGH);
440 }
441 return (0);
442 }
443
444 /*
445 * Queue a packet. Start transmission if not active.
446 * Compression happens in slintr(); if we do it here, IP TOS
447 * will cause us to not compress "background" packets, because
448 * ordering gets trashed. It can be done for all packets in slintr().
449 */
450 static int
451 sloutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
452 struct rtentry *rtp)
453 {
454 struct sl_softc *sc = ifp->if_softc;
455 struct ip *ip;
456 struct ifqueue *ifq = NULL;
457 int s, error;
458 ALTQ_DECL(struct altq_pktattr pktattr;)
459
460 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr);
461
462 /*
463 * `Cannot happen' (see slioctl). Someday we will extend
464 * the line protocol to support other address families.
465 */
466 if (dst->sa_family != AF_INET) {
467 printf("%s: af%d not supported\n", sc->sc_if.if_xname,
468 dst->sa_family);
469 m_freem(m);
470 sc->sc_if.if_noproto++;
471 return (EAFNOSUPPORT);
472 }
473
474 if (sc->sc_ttyp == NULL) {
475 m_freem(m);
476 return (ENETDOWN); /* sort of */
477 }
478 if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 &&
479 (sc->sc_ttyp->t_cflag & CLOCAL) == 0) {
480 m_freem(m);
481 printf("%s: no carrier and not local\n", sc->sc_if.if_xname);
482 return (EHOSTUNREACH);
483 }
484 ip = mtod(m, struct ip *);
485 #ifdef INET
486 if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) {
487 m_freem(m);
488 return (ENETRESET); /* XXX ? */
489 }
490 #endif
491
492 s = spltty();
493 if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) {
494 struct bintime bt;
495
496 /* if output's been stalled for too long, and restart */
497 getbinuptime(&bt);
498 bintime_sub(&bt, &sc->sc_lastpacket);
499 if (bt.sec > 0) {
500 sc->sc_otimeout++;
501 slstart(sc->sc_ttyp);
502 }
503 }
504 splx(s);
505
506 s = splnet();
507 #ifdef INET
508 if ((ip->ip_tos & IPTOS_LOWDELAY) != 0)
509 ifq = &sc->sc_fastq;
510 #endif
511 if ((error = ifq_enqueue2(ifp, ifq, m ALTQ_COMMA
512 ALTQ_DECL(&pktattr))) != 0) {
513 splx(s);
514 return error;
515 }
516 getbinuptime(&sc->sc_lastpacket);
517 splx(s);
518
519 s = spltty();
520 if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0)
521 slstart(sc->sc_ttyp);
522 splx(s);
523
524 return (0);
525 }
526
527 /*
528 * Start output on interface. Get another datagram
529 * to send from the interface queue and map it to
530 * the interface before starting output.
531 */
532 static int
533 slstart(struct tty *tp)
534 {
535 struct sl_softc *sc = tp->t_sc;
536
537 /*
538 * If there is more in the output queue, just send it now.
539 * We are being called in lieu of ttstart and must do what
540 * it would.
541 */
542 if (tp->t_outq.c_cc != 0) {
543 (*tp->t_oproc)(tp);
544 if (tp->t_outq.c_cc > SLIP_HIWAT)
545 return (0);
546 }
547
548 /*
549 * This happens briefly when the line shuts down.
550 */
551 if (sc == NULL)
552 return (0);
553 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
554 softintr_schedule(sc->sc_si);
555 #else
556 {
557 int s = splhigh();
558 schednetisr(NETISR_SLIP);
559 splx(s);
560 }
561 #endif
562 return (0);
563 }
564
565 /*
566 * Copy data buffer to mbuf chain; add ifnet pointer.
567 */
568 static struct mbuf *
569 sl_btom(struct sl_softc *sc, int len)
570 {
571 struct mbuf *m;
572
573 /*
574 * Allocate a new input buffer and swap.
575 */
576 m = sc->sc_mbuf;
577 MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA);
578 if (sc->sc_mbuf == NULL) {
579 sc->sc_mbuf = m;
580 return (NULL);
581 }
582 MCLGET(sc->sc_mbuf, M_DONTWAIT);
583 if ((sc->sc_mbuf->m_flags & M_EXT) == 0) {
584 m_freem(sc->sc_mbuf);
585 sc->sc_mbuf = m;
586 return (NULL);
587 }
588 sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf +
589 sc->sc_mbuf->m_ext.ext_size;
590
591 m->m_data = sc->sc_pktstart;
592
593 m->m_pkthdr.len = m->m_len = len;
594 m->m_pkthdr.rcvif = &sc->sc_if;
595 return (m);
596 }
597
598 /*
599 * tty interface receiver interrupt.
600 */
601 static int
602 slinput(int c, struct tty *tp)
603 {
604 struct sl_softc *sc;
605 struct mbuf *m;
606 int len;
607
608 tk_nin++;
609 sc = (struct sl_softc *)tp->t_sc;
610 if (sc == NULL)
611 return (0);
612 if ((c & TTY_ERRORMASK) || ((tp->t_state & TS_CARR_ON) == 0 &&
613 (tp->t_cflag & CLOCAL) == 0)) {
614 sc->sc_flags |= SC_ERROR;
615 return (0);
616 }
617 c &= TTY_CHARMASK;
618
619 ++sc->sc_if.if_ibytes;
620
621 if (sc->sc_if.if_flags & IFF_DEBUG) {
622 if (c == ABT_ESC) {
623 /*
624 * If we have a previous abort, see whether
625 * this one is within the time limit.
626 */
627 if (sc->sc_abortcount &&
628 time_second >= sc->sc_starttime + ABT_WINDOW)
629 sc->sc_abortcount = 0;
630 /*
631 * If we see an abort after "idle" time, count it;
632 * record when the first abort escape arrived.
633 */
634 if (time_second >= sc->sc_lasttime + ABT_IDLE) {
635 if (++sc->sc_abortcount == 1)
636 sc->sc_starttime = time_second;
637 if (sc->sc_abortcount >= ABT_COUNT) {
638 slclose(tp, 0);
639 return (0);
640 }
641 }
642 } else
643 sc->sc_abortcount = 0;
644 sc->sc_lasttime = time_second;
645 }
646
647 switch (c) {
648
649 case TRANS_FRAME_ESCAPE:
650 if (sc->sc_escape)
651 c = FRAME_ESCAPE;
652 break;
653
654 case TRANS_FRAME_END:
655 if (sc->sc_escape)
656 c = FRAME_END;
657 break;
658
659 case FRAME_ESCAPE:
660 sc->sc_escape = 1;
661 return (0);
662
663 case FRAME_END:
664 if(sc->sc_flags & SC_ERROR) {
665 sc->sc_flags &= ~SC_ERROR;
666 goto newpack;
667 }
668 len = sc->sc_mp - sc->sc_pktstart;
669 if (len < 3)
670 /* less than min length packet - ignore */
671 goto newpack;
672
673 m = sl_btom(sc, len);
674 if (m == NULL)
675 goto error;
676
677 IF_ENQUEUE(&sc->sc_inq, m);
678 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
679 softintr_schedule(sc->sc_si);
680 #else
681 {
682 int s = splhigh();
683 schednetisr(NETISR_SLIP);
684 splx(s);
685 }
686 #endif
687 goto newpack;
688 }
689 if (sc->sc_mp < sc->sc_ep) {
690 *sc->sc_mp++ = c;
691 sc->sc_escape = 0;
692 return (0);
693 }
694
695 /* can't put lower; would miss an extra frame */
696 sc->sc_flags |= SC_ERROR;
697
698 error:
699 sc->sc_if.if_ierrors++;
700 newpack:
701 sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf +
702 BUFOFFSET;
703 sc->sc_escape = 0;
704
705 return (0);
706 }
707
708 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS
709 void
710 slnetisr(void)
711 {
712 struct sl_softc *sc;
713
714 LIST_FOREACH(sc, &sl_softc_list, sc_iflist) {
715 if (sc->sc_ttyp == NULL)
716 continue;
717 slintr(sc);
718 }
719 }
720 #endif
721
722 static void
723 slintr(void *arg)
724 {
725 struct sl_softc *sc = arg;
726 struct tty *tp = sc->sc_ttyp;
727 struct mbuf *m;
728 int s, len;
729 u_char *pktstart;
730 #ifdef INET
731 u_char c;
732 #endif
733 #if NBPFILTER > 0
734 u_char chdr[CHDR_LEN];
735 #endif
736
737 KASSERT(tp != NULL);
738
739 /*
740 * Output processing loop.
741 */
742 for (;;) {
743 #ifdef INET
744 struct ip *ip;
745 #endif
746 struct mbuf *m2;
747 #if NBPFILTER > 0
748 struct mbuf *bpf_m;
749 #endif
750
751 /*
752 * Do not remove the packet from the queue if it
753 * doesn't look like it will fit into the current
754 * serial output queue. With a packet full of
755 * escapes, this could be as bad as MTU*2+2.
756 */
757 s = spltty();
758 if (tp->t_outq.c_cn - tp->t_outq.c_cc <
759 2*sc->sc_if.if_mtu+2) {
760 splx(s);
761 break;
762 }
763 splx(s);
764
765 /*
766 * Get a packet and send it to the interface.
767 */
768 s = splnet();
769 IF_DEQUEUE(&sc->sc_fastq, m);
770 if (m)
771 sc->sc_if.if_omcasts++; /* XXX */
772 else
773 IFQ_DEQUEUE(&sc->sc_if.if_snd, m);
774 splx(s);
775
776 if (m == NULL)
777 break;
778
779 /*
780 * We do the header compression here rather than in
781 * sloutput() because the packets will be out of order
782 * if we are using TOS queueing, and the connection
783 * ID compression will get munged when this happens.
784 */
785 #if NBPFILTER > 0
786 if (sc->sc_if.if_bpf) {
787 /*
788 * We need to save the TCP/IP header before
789 * it's compressed. To avoid complicated
790 * code, we just make a deep copy of the
791 * entire packet (since this is a serial
792 * line, packets should be short and/or the
793 * copy should be negligible cost compared
794 * to the packet transmission time).
795 */
796 bpf_m = m_dup(m, 0, M_COPYALL, M_DONTWAIT);
797 } else
798 bpf_m = NULL;
799 #endif
800 #ifdef INET
801 if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) {
802 if (sc->sc_if.if_flags & SC_COMPRESS)
803 *mtod(m, u_char *) |=
804 sl_compress_tcp(m, ip,
805 &sc->sc_comp, 1);
806 }
807 #endif
808 #if NBPFILTER > 0
809 if (sc->sc_if.if_bpf && bpf_m != NULL)
810 bpf_mtap_sl_out(sc->sc_if.if_bpf, mtod(m, u_char *),
811 bpf_m);
812 #endif
813 getbinuptime(&sc->sc_lastpacket);
814
815 s = spltty();
816
817 /*
818 * The extra FRAME_END will start up a new packet,
819 * and thus will flush any accumulated garbage. We
820 * do this whenever the line may have been idle for
821 * some time.
822 */
823 if (tp->t_outq.c_cc == 0) {
824 sc->sc_if.if_obytes++;
825 (void) putc(FRAME_END, &tp->t_outq);
826 }
827
828 while (m) {
829 u_char *bp, *cp, *ep;
830
831 bp = cp = mtod(m, u_char *);
832 ep = cp + m->m_len;
833 while (cp < ep) {
834 /*
835 * Find out how many bytes in the
836 * string we can handle without
837 * doing something special.
838 */
839 while (cp < ep) {
840 switch (*cp++) {
841 case FRAME_ESCAPE:
842 case FRAME_END:
843 cp--;
844 goto out;
845 }
846 }
847 out:
848 if (cp > bp) {
849 /*
850 * Put N characters at once
851 * into the tty output queue.
852 */
853 if (b_to_q(bp, cp - bp,
854 &tp->t_outq))
855 break;
856 sc->sc_if.if_obytes += cp - bp;
857 }
858 /*
859 * If there are characters left in
860 * the mbuf, the first one must be
861 * special.. Put it out in a different
862 * form.
863 */
864 if (cp < ep) {
865 if (putc(FRAME_ESCAPE,
866 &tp->t_outq))
867 break;
868 if (putc(*cp++ == FRAME_ESCAPE ?
869 TRANS_FRAME_ESCAPE :
870 TRANS_FRAME_END,
871 &tp->t_outq)) {
872 (void)
873 unputc(&tp->t_outq);
874 break;
875 }
876 sc->sc_if.if_obytes += 2;
877 }
878 bp = cp;
879 }
880 MFREE(m, m2);
881 m = m2;
882 }
883
884 if (putc(FRAME_END, &tp->t_outq)) {
885 /*
886 * Not enough room. Remove a char to make
887 * room and end the packet normally. If
888 * you get many collisions (more than one
889 * or two a day), you probably do not have
890 * enough clists and you should increase
891 * "nclist" in param.c
892 */
893 (void) unputc(&tp->t_outq);
894 (void) putc(FRAME_END, &tp->t_outq);
895 sc->sc_if.if_collisions++;
896 } else {
897 sc->sc_if.if_obytes++;
898 sc->sc_if.if_opackets++;
899 }
900
901 /*
902 * We now have characters in the output queue,
903 * kick the serial port.
904 */
905 (*tp->t_oproc)(tp);
906 splx(s);
907 }
908
909 /*
910 * Input processing loop.
911 */
912 for (;;) {
913 s = spltty();
914 IF_DEQUEUE(&sc->sc_inq, m);
915 splx(s);
916 if (m == NULL)
917 break;
918 pktstart = mtod(m, u_char *);
919 len = m->m_pkthdr.len;
920 #if NBPFILTER > 0
921 if (sc->sc_if.if_bpf) {
922 /*
923 * Save the compressed header, so we
924 * can tack it on later. Note that we
925 * will end up copying garbage in some
926 * cases but this is okay. We remember
927 * where the buffer started so we can
928 * compute the new header length.
929 */
930 memcpy(chdr, pktstart, CHDR_LEN);
931 }
932 #endif /* NBPFILTER > 0 */
933 #ifdef INET
934 if ((c = (*pktstart & 0xf0)) != (IPVERSION << 4)) {
935 if (c & 0x80)
936 c = TYPE_COMPRESSED_TCP;
937 else if (c == TYPE_UNCOMPRESSED_TCP)
938 *pktstart &= 0x4f; /* XXX */
939 /*
940 * We've got something that's not an IP
941 * packet. If compression is enabled,
942 * try to decompress it. Otherwise, if
943 * `auto-enable' compression is on and
944 * it's a reasonable packet, decompress
945 * it and then enable compression.
946 * Otherwise, drop it.
947 */
948 if (sc->sc_if.if_flags & SC_COMPRESS) {
949 len = sl_uncompress_tcp(&pktstart, len,
950 (u_int)c, &sc->sc_comp);
951 if (len <= 0) {
952 m_freem(m);
953 continue;
954 }
955 } else if ((sc->sc_if.if_flags & SC_AUTOCOMP) &&
956 c == TYPE_UNCOMPRESSED_TCP && len >= 40) {
957 len = sl_uncompress_tcp(&pktstart, len,
958 (u_int)c, &sc->sc_comp);
959 if (len <= 0) {
960 m_freem(m);
961 continue;
962 }
963 sc->sc_if.if_flags |= SC_COMPRESS;
964 } else {
965 m_freem(m);
966 continue;
967 }
968 }
969 #endif
970 m->m_data = (caddr_t) pktstart;
971 m->m_pkthdr.len = m->m_len = len;
972 #if NBPFILTER > 0
973 if (sc->sc_if.if_bpf) {
974 bpf_mtap_sl_in(sc->sc_if.if_bpf, chdr, &m);
975 if (m == NULL)
976 continue;
977 }
978 #endif /* NBPFILTER > 0 */
979 /*
980 * If the packet will fit into a single
981 * header mbuf, copy it into one, to save
982 * memory.
983 */
984 if (m->m_pkthdr.len < MHLEN) {
985 struct mbuf *n;
986 int pktlen;
987
988 MGETHDR(n, M_DONTWAIT, MT_DATA);
989 pktlen = m->m_pkthdr.len;
990 M_MOVE_PKTHDR(n, m);
991 memcpy(mtod(n, caddr_t), mtod(m, caddr_t), pktlen);
992 n->m_len = m->m_len;
993 m_freem(m);
994 m = n;
995 }
996
997 sc->sc_if.if_ipackets++;
998 getbinuptime(&sc->sc_lastpacket);
999
1000 #ifdef INET
1001 s = splnet();
1002 if (IF_QFULL(&ipintrq)) {
1003 IF_DROP(&ipintrq);
1004 sc->sc_if.if_ierrors++;
1005 sc->sc_if.if_iqdrops++;
1006 m_freem(m);
1007 } else {
1008 IF_ENQUEUE(&ipintrq, m);
1009 schednetisr(NETISR_IP);
1010 }
1011 splx(s);
1012 #endif
1013 }
1014 }
1015
1016 /*
1017 * Process an ioctl request.
1018 */
1019 static int
1020 slioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
1021 {
1022 struct ifaddr *ifa = (struct ifaddr *)data;
1023 struct ifreq *ifr = (struct ifreq *)data;
1024 int s = splnet(), error = 0;
1025 struct sl_softc *sc = ifp->if_softc;
1026 struct ppp_stats *psp;
1027 struct ppp_comp_stats *pcp;
1028
1029 switch (cmd) {
1030
1031 case SIOCSIFADDR:
1032 if (ifa->ifa_addr->sa_family == AF_INET)
1033 ifp->if_flags |= IFF_UP;
1034 else
1035 error = EAFNOSUPPORT;
1036 break;
1037
1038 case SIOCSIFDSTADDR:
1039 if (ifa->ifa_addr->sa_family != AF_INET)
1040 error = EAFNOSUPPORT;
1041 break;
1042
1043 case SIOCSIFMTU:
1044 if ((ifr->ifr_mtu < 3) || (ifr->ifr_mtu > SLMAX)) {
1045 error = EINVAL;
1046 break;
1047 }
1048 sc->sc_if.if_mtu = ifr->ifr_mtu;
1049 break;
1050
1051 case SIOCGIFMTU:
1052 ifr->ifr_mtu = sc->sc_if.if_mtu;
1053 break;
1054
1055 case SIOCADDMULTI:
1056 case SIOCDELMULTI:
1057 if (ifr == 0) {
1058 error = EAFNOSUPPORT; /* XXX */
1059 break;
1060 }
1061 switch (ifr->ifr_addr.sa_family) {
1062
1063 #ifdef INET
1064 case AF_INET:
1065 break;
1066 #endif
1067
1068 default:
1069 error = EAFNOSUPPORT;
1070 break;
1071 }
1072 break;
1073
1074 case SIOCGPPPSTATS:
1075 psp = &((struct ifpppstatsreq *) data)->stats;
1076 (void)memset(psp, 0, sizeof(*psp));
1077 psp->p.ppp_ibytes = sc->sc_if.if_ibytes;
1078 psp->p.ppp_ipackets = sc->sc_if.if_ipackets;
1079 psp->p.ppp_ierrors = sc->sc_if.if_ierrors;
1080 psp->p.ppp_obytes = sc->sc_if.if_obytes;
1081 psp->p.ppp_opackets = sc->sc_if.if_opackets;
1082 psp->p.ppp_oerrors = sc->sc_if.if_oerrors;
1083 #ifdef INET
1084 psp->vj.vjs_packets = sc->sc_comp.sls_packets;
1085 psp->vj.vjs_compressed = sc->sc_comp.sls_compressed;
1086 psp->vj.vjs_searches = sc->sc_comp.sls_searches;
1087 psp->vj.vjs_misses = sc->sc_comp.sls_misses;
1088 psp->vj.vjs_uncompressedin = sc->sc_comp.sls_uncompressedin;
1089 psp->vj.vjs_compressedin = sc->sc_comp.sls_compressedin;
1090 psp->vj.vjs_errorin = sc->sc_comp.sls_errorin;
1091 psp->vj.vjs_tossed = sc->sc_comp.sls_tossed;
1092 #endif
1093 break;
1094
1095 case SIOCGPPPCSTATS:
1096 pcp = &((struct ifpppcstatsreq *) data)->stats;
1097 (void)memset(pcp, 0, sizeof(*pcp));
1098 break;
1099
1100 default:
1101 error = EINVAL;
1102 }
1103 splx(s);
1104 return (error);
1105 }
1106