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1.1 nbrk 1: /* $OpenBSD: if_sl.c,v 1.32 2006/03/25 22:41:47 djm Exp $ */
2: /* $NetBSD: if_sl.c,v 1.39.4.1 1996/06/02 16:26:31 thorpej Exp $ */
3:
4: /*
5: * Copyright (c) 1987, 1989, 1992, 1993
6: * The Regents of the University of California. All rights reserved.
7: *
8: * Redistribution and use in source and binary forms, with or without
9: * modification, are permitted provided that the following conditions
10: * are met:
11: * 1. Redistributions of source code must retain the above copyright
12: * notice, this list of conditions and the following disclaimer.
13: * 2. Redistributions in binary form must reproduce the above copyright
14: * notice, this list of conditions and the following disclaimer in the
15: * documentation and/or other materials provided with the distribution.
16: * 3. Neither the name of the University nor the names of its contributors
17: * may be used to endorse or promote products derived from this software
18: * without specific prior written permission.
19: *
20: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30: * SUCH DAMAGE.
31: *
32: * @(#)if_sl.c 8.6 (Berkeley) 2/1/94
33: */
34:
35: /*
36: * Serial Line interface
37: *
38: * Rick Adams
39: * Center for Seismic Studies
40: * 1300 N 17th Street, Suite 1450
41: * Arlington, Virginia 22209
42: * (703)276-7900
43: * rick@seismo.ARPA
44: * seismo!rick
45: *
46: * Pounded on heavily by Chris Torek (chris@mimsy.umd.edu, umcp-cs!chris).
47: * N.B.: this belongs in netinet, not net, the way it stands now.
48: * Should have a link-layer type designation, but wouldn't be
49: * backwards-compatible.
50: *
51: * Converted to 4.3BSD Beta by Chris Torek.
52: * Other changes made at Berkeley, based in part on code by Kirk Smith.
53: * W. Jolitz added slip abort.
54: *
55: * Hacked almost beyond recognition by Van Jacobson (van@helios.ee.lbl.gov).
56: * Added priority queuing for "interactive" traffic; hooks for TCP
57: * header compression; ICMP filtering (at 2400 baud, some cretin
58: * pinging you can use up all your bandwidth). Made low clist behavior
59: * more robust and slightly less likely to hang serial line.
60: * Sped up a bunch of things.
61: */
62:
63: #include "bpfilter.h"
64:
65: #include <sys/param.h>
66: #include <sys/proc.h>
67: #include <sys/mbuf.h>
68: #include <sys/dkstat.h>
69: #include <sys/socket.h>
70: #include <sys/ioctl.h>
71: #include <sys/file.h>
72: #include <sys/tty.h>
73: #include <sys/kernel.h>
74: #include <sys/conf.h>
75: #if defined(__NetBSD__) || defined(__OpenBSD__)
76: #include <sys/systm.h>
77: #endif
78:
79: #include <machine/cpu.h>
80:
81: #include <net/if.h>
82: #include <net/if_types.h>
83: #include <net/netisr.h>
84: #include <net/route.h>
85:
86: #if INET
87: #include <netinet/in.h>
88: #include <netinet/in_systm.h>
89: #include <netinet/in_var.h>
90: #include <netinet/ip.h>
91: #else
92: #error Huh? Slip without inet?
93: #endif
94:
95: #include <net/slcompress.h>
96: #include <net/if_slvar.h>
97: #include <net/slip.h>
98:
99: #if NBPFILTER > 0
100: #include <sys/time.h>
101: #include <net/bpf.h>
102: #endif
103:
104: /*
105: * SLMAX is a hard limit on input packet size. To simplify the code
106: * and improve performance, we require that packets fit in an mbuf
107: * cluster, and if we get a compressed packet, there's enough extra
108: * room to expand the header into a max length tcp/ip header (128
109: * bytes). So, SLMAX can be at most
110: * MCLBYTES - 128
111: *
112: * SLMTU is a hard limit on output packet size. To insure good
113: * interactive response, SLMTU wants to be the smallest size that
114: * amortizes the header cost. (Remember that even with
115: * type-of-service queuing, we have to wait for any in-progress
116: * packet to finish. I.e., we wait, on the average, 1/2 * mtu /
117: * cps, where cps is the line speed in characters per second.
118: * E.g., 533ms wait for a 1024 byte MTU on a 9600 baud line. The
119: * average compressed header size is 6-8 bytes so any MTU > 90
120: * bytes will give us 90% of the line bandwidth. A 100ms wait is
121: * tolerable (500ms is not), so want an MTU around 296. (Since TCP
122: * will send 256 byte segments (to allow for 40 byte headers), the
123: * typical packet size on the wire will be around 260 bytes). In
124: * 4.3tahoe+ systems, we can set an MTU in a route so we do that &
125: * leave the interface MTU relatively high (so we don't IP fragment
126: * when acting as a gateway to someone using a stupid MTU).
127: *
128: * Similar considerations apply to SLIP_HIWAT: It's the amount of
129: * data that will be queued 'downstream' of us (i.e., in clists
130: * waiting to be picked up by the tty output interrupt). If we
131: * queue a lot of data downstream, it's immune to our t.o.s. queuing.
132: * E.g., if SLIP_HIWAT is 1024, the interactive traffic in mixed
133: * telnet/ftp will see a 1 sec wait, independent of the mtu (the
134: * wait is dependent on the ftp window size but that's typically
135: * 1k - 4k). So, we want SLIP_HIWAT just big enough to amortize
136: * the cost (in idle time on the wire) of the tty driver running
137: * off the end of its clists & having to call back slstart for a
138: * new packet. For a tty interface with any buffering at all, this
139: * cost will be zero. Even with a totally brain dead interface (like
140: * the one on a typical workstation), the cost will be <= 1 character
141: * time. So, setting SLIP_HIWAT to ~100 guarantees that we'll lose
142: * at most 1% while maintaining good interactive response.
143: */
144: #if NBPFILTER > 0
145: #define BUFOFFSET (128+sizeof(struct ifnet **)+SLIP_HDRLEN)
146: #else
147: #define BUFOFFSET (128+sizeof(struct ifnet **))
148: #endif
149: #define SLMAX (MCLBYTES - BUFOFFSET)
150: #define SLBUFSIZE (SLMAX + BUFOFFSET)
151: #ifndef SLMTU
152: #define SLMTU 296
153: #endif
154: #if (SLMTU < 3)
155: #error Huh? SLMTU way too small.
156: #endif
157: #define SLIP_HIWAT roundup(50,CBSIZE)
158: #if !(defined(__NetBSD__) || defined(__OpenBSD__)) /* XXX - cgd */
159: #define CLISTRESERVE 1024 /* Can't let clists get too low */
160: #endif /* !NetBSD */
161:
162: /*
163: * SLIP ABORT ESCAPE MECHANISM:
164: * (inspired by HAYES modem escape arrangement)
165: * 1sec escape 1sec escape 1sec escape { 1sec escape 1sec escape }
166: * within window time signals a "soft" exit from slip mode by remote end
167: * if the IFF_DEBUG flag is on.
168: */
169: #define ABT_ESC '\033' /* can't be t_intr - distant host must know it*/
170: #define ABT_IDLE 1 /* in seconds - idle before an escape */
171: #define ABT_COUNT 3 /* count of escapes for abort */
172: #define ABT_WINDOW (ABT_COUNT*2+2) /* in seconds - time to count */
173:
174:
175: #define FRAME_END 0xc0 /* Frame End */
176: #define FRAME_ESCAPE 0xdb /* Frame Esc */
177: #define TRANS_FRAME_END 0xdc /* transposed frame end */
178: #define TRANS_FRAME_ESCAPE 0xdd /* transposed frame esc */
179:
180: static int slinit(struct sl_softc *);
181: static struct mbuf *sl_btom(struct sl_softc *, int);
182:
183: int sl_clone_create(struct if_clone *, int);
184: int sl_clone_destroy(struct ifnet *);
185:
186: LIST_HEAD(, sl_softc) sl_softc_list;
187: struct if_clone sl_cloner =
188: IF_CLONE_INITIALIZER("sl", sl_clone_create, sl_clone_destroy);
189:
190: /*
191: * Called from boot code to establish sl interfaces.
192: */
193: void
194: slattach(n)
195: int n;
196: {
197: LIST_INIT(&sl_softc_list);
198: if_clone_attach(&sl_cloner);
199: }
200:
201: int
202: sl_clone_create(ifc, unit)
203: struct if_clone *ifc;
204: int unit;
205: {
206: struct sl_softc *sc;
207: int s;
208:
209: sc = malloc(sizeof(*sc), M_DEVBUF, M_NOWAIT);
210: if (!sc)
211: return (ENOMEM);
212: bzero(sc, sizeof(*sc));
213:
214: sc->sc_unit = unit; /* XXX */
215: snprintf(sc->sc_if.if_xname, sizeof sc->sc_if.if_xname, "%s%d",
216: ifc->ifc_name, unit);
217: sc->sc_if.if_softc = sc;
218: sc->sc_if.if_mtu = SLMTU;
219: sc->sc_if.if_flags =
220: IFF_POINTOPOINT | SC_AUTOCOMP | IFF_MULTICAST;
221: sc->sc_if.if_type = IFT_SLIP;
222: sc->sc_if.if_ioctl = slioctl;
223: sc->sc_if.if_output = sloutput;
224: IFQ_SET_MAXLEN(&sc->sc_if.if_snd, 50);
225: sc->sc_fastq.ifq_maxlen = 32;
226: IFQ_SET_READY(&sc->sc_if.if_snd);
227: if_attach(&sc->sc_if);
228: if_alloc_sadl(&sc->sc_if);
229: #if NBPFILTER > 0
230: bpfattach(&sc->sc_bpf, &sc->sc_if, DLT_SLIP, SLIP_HDRLEN);
231: #endif
232: s = splnet();
233: LIST_INSERT_HEAD(&sl_softc_list, sc, sc_list);
234: splx(s);
235:
236: return (0);
237: }
238:
239: int
240: sl_clone_destroy(ifp)
241: struct ifnet *ifp;
242: {
243: struct sl_softc *sc = ifp->if_softc;
244: int s;
245:
246: if (sc->sc_ttyp != NULL)
247: return (EBUSY);
248:
249: s = splnet();
250: LIST_REMOVE(sc, sc_list);
251: splx(s);
252:
253: if_detach(ifp);
254:
255: free(sc, M_DEVBUF);
256: return (0);
257: }
258:
259: static int
260: slinit(sc)
261: struct sl_softc *sc;
262: {
263: if (sc->sc_ep == (u_char *) 0) {
264: MGETHDR(sc->sc_mbuf, M_WAIT, MT_DATA);
265: if (sc->sc_mbuf)
266: MCLGET(sc->sc_mbuf, M_WAIT);
267: if (sc->sc_mbuf == NULL || sc->sc_mbuf->m_ext.ext_buf == NULL) {
268: printf("sl%d: can't allocate buffer\n", sc->sc_unit);
269: sc->sc_if.if_flags &= ~IFF_UP;
270: return (0);
271: }
272: }
273: sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf +
274: sc->sc_mbuf->m_ext.ext_size;
275: sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf +
276: BUFOFFSET;
277:
278: sl_compress_init(&sc->sc_comp);
279:
280: return (1);
281: }
282:
283: /*
284: * Line specific open routine.
285: * Attach the given tty to the first available sl unit.
286: */
287: /* ARGSUSED */
288: int
289: slopen(dev, tp)
290: dev_t dev;
291: struct tty *tp;
292: {
293: struct proc *p = curproc; /* XXX */
294: struct sl_softc *sc;
295: int error, s;
296:
297: if ((error = suser(p, 0)) != 0)
298: return (error);
299:
300: if (tp->t_line == SLIPDISC)
301: return (0);
302:
303: LIST_FOREACH(sc, &sl_softc_list, sc_list)
304: if (sc->sc_ttyp == NULL) {
305: if (slinit(sc) == 0)
306: return (ENOBUFS);
307: tp->t_sc = (caddr_t)sc;
308: sc->sc_ttyp = tp;
309: sc->sc_if.if_baudrate = tp->t_ospeed;
310: s = spltty();
311: tp->t_state |= TS_ISOPEN | TS_XCLUDE;
312: splx(s);
313: ttyflush(tp, FREAD | FWRITE);
314: #if defined(__NetBSD__) || defined(__OpenBSD__)
315: /*
316: * make sure tty output queue is large enough
317: * to hold a full-sized packet (including frame
318: * end, and a possible extra frame end). full-sized
319: * packet occupies a max of 2*SLMTU bytes (because
320: * of possible escapes), and add two on for frame
321: * ends.
322: */
323: s = spltty();
324: if (tp->t_outq.c_cn < 2*SLMTU+2) {
325: sc->sc_oldbufsize = tp->t_outq.c_cn;
326: sc->sc_oldbufquot = tp->t_outq.c_cq != 0;
327:
328: clfree(&tp->t_outq);
329: error = clalloc(&tp->t_outq, 3*SLMTU, 0);
330: if (error) {
331: splx(s);
332: return (error);
333: }
334: } else
335: sc->sc_oldbufsize = sc->sc_oldbufquot = 0;
336: splx(s);
337: #endif /* NetBSD */
338: return (0);
339: }
340: return (ENXIO);
341: }
342:
343: /*
344: * Line specific close routine.
345: * Detach the tty from the sl unit.
346: */
347: void
348: slclose(tp)
349: struct tty *tp;
350: {
351: struct sl_softc *sc;
352: int s;
353:
354: ttywflush(tp);
355: tp->t_line = 0;
356: sc = (struct sl_softc *)tp->t_sc;
357: if (sc != NULL) {
358: s = spltty();
359:
360: if_down(&sc->sc_if);
361: sc->sc_ttyp = NULL;
362: tp->t_sc = NULL;
363:
364: m_freem(sc->sc_mbuf);
365: sc->sc_mbuf = NULL;
366: sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL;
367:
368: #if defined(__NetBSD__) || defined(__OpenBSD__)
369: /* if necessary, install a new outq buffer of the appropriate size */
370: if (sc->sc_oldbufsize != 0) {
371: clfree(&tp->t_outq);
372: clalloc(&tp->t_outq, sc->sc_oldbufsize, sc->sc_oldbufquot);
373: }
374: #endif
375: splx(s);
376: }
377: }
378:
379: /*
380: * Line specific (tty) ioctl routine.
381: * Provide a way to get the sl unit number.
382: */
383: /* ARGSUSED */
384: int
385: sltioctl(tp, cmd, data, flag)
386: struct tty *tp;
387: u_long cmd;
388: caddr_t data;
389: int flag;
390: {
391: struct sl_softc *sc = (struct sl_softc *)tp->t_sc;
392:
393: switch (cmd) {
394: case SLIOCGUNIT:
395: *(int *)data = sc->sc_unit; /* XXX */
396: break;
397:
398: default:
399: return (-1);
400: }
401: return (0);
402: }
403:
404: /*
405: * Queue a packet. Start transmission if not active.
406: * Compression happens in slstart; if we do it here, IP TOS
407: * will cause us to not compress "background" packets, because
408: * ordering gets trashed. It can be done for all packets in slstart.
409: */
410: int
411: sloutput(ifp, m, dst, rtp)
412: struct ifnet *ifp;
413: struct mbuf *m;
414: struct sockaddr *dst;
415: struct rtentry *rtp;
416: {
417: struct sl_softc *sc = ifp->if_softc;
418: struct ip *ip;
419: int s, error;
420:
421: /*
422: * `Cannot happen' (see slioctl). Someday we will extend
423: * the line protocol to support other address families.
424: */
425: if (dst->sa_family != AF_INET) {
426: printf("%s: af%d not supported\n", sc->sc_if.if_xname,
427: dst->sa_family);
428: m_freem(m);
429: sc->sc_if.if_noproto++;
430: return (EAFNOSUPPORT);
431: }
432:
433: if (sc->sc_ttyp == NULL) {
434: m_freem(m);
435: return (ENETDOWN); /* sort of */
436: }
437: if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 &&
438: (sc->sc_ttyp->t_cflag & CLOCAL) == 0) {
439: m_freem(m);
440: return (EHOSTUNREACH);
441: }
442: ip = mtod(m, struct ip *);
443: if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) {
444: m_freem(m);
445: return (ENETRESET); /* XXX ? */
446: }
447: s = spltty();
448: if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) {
449: struct timeval tv, tm;
450:
451: getmicrotime(&tm);
452: /* if output's been stalled for too long, and restart */
453: timersub(&tm, &sc->sc_lastpacket, &tv);
454: if (tv.tv_sec > 0) {
455: sc->sc_otimeout++;
456: slstart(sc->sc_ttyp);
457: }
458: }
459:
460: (void) splnet();
461: IFQ_ENQUEUE(&sc->sc_if.if_snd, m, NULL, error);
462: if (error) {
463: splx(s);
464: sc->sc_if.if_oerrors++;
465: return (error);
466: }
467:
468: (void) spltty();
469: getmicrotime(&sc->sc_lastpacket);
470: if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0)
471: slstart(sc->sc_ttyp);
472: splx(s);
473: return (0);
474: }
475:
476: /*
477: * Start output on interface. Get another datagram
478: * to send from the interface queue and map it to
479: * the interface before starting output.
480: */
481: void
482: slstart(tp)
483: struct tty *tp;
484: {
485: struct sl_softc *sc = (struct sl_softc *)tp->t_sc;
486: struct mbuf *m;
487: u_char *cp;
488: struct ip *ip;
489: int s;
490: struct mbuf *m2;
491: #if NBPFILTER > 0
492: u_char bpfbuf[SLMTU + SLIP_HDRLEN];
493: int len = 0;
494: #endif
495: #if !(defined(__NetBSD__) || defined(__OpenBSD__)) /* XXX - cgd */
496: extern int cfreecount;
497: #endif
498:
499: for (;;) {
500: /*
501: * If there is more in the output queue, just send it now.
502: * We are being called in lieu of ttstart and must do what
503: * it would.
504: */
505: if (tp->t_outq.c_cc != 0) {
506: (*tp->t_oproc)(tp);
507: if (tp->t_outq.c_cc > SLIP_HIWAT)
508: return;
509: }
510: /*
511: * This happens briefly when the line shuts down.
512: */
513: if (sc == NULL)
514: return;
515:
516: #if defined(__NetBSD__) || defined(__OpenBSD__) /* XXX - cgd */
517: /*
518: * Do not remove the packet from the IP queue if it
519: * doesn't look like the packet will fit into the
520: * current serial output queue, with a packet full of
521: * escapes this could be as bad as SLMTU*2+2.
522: */
523: if (tp->t_outq.c_cn - tp->t_outq.c_cc < 2*SLMTU+2)
524: return;
525: #endif /* NetBSD */
526:
527: /*
528: * Get a packet and send it to the interface.
529: */
530: s = splnet();
531: IF_DEQUEUE(&sc->sc_fastq, m);
532: if (m)
533: sc->sc_if.if_omcasts++; /* XXX */
534: else
535: IFQ_DEQUEUE(&sc->sc_if.if_snd, m);
536: splx(s);
537: if (m == NULL)
538: return;
539:
540: /*
541: * We do the header compression here rather than in sloutput
542: * because the packets will be out of order if we are using TOS
543: * queueing, and the connection id compression will get
544: * munged when this happens.
545: */
546: #if NBPFILTER > 0
547: if (sc->sc_bpf) {
548: /*
549: * We need to save the TCP/IP header before it's
550: * compressed. To avoid complicated code, we just
551: * copy the entire packet into a stack buffer (since
552: * this is a serial line, packets should be short
553: * and/or the copy should be negligible cost compared
554: * to the packet transmission time).
555: */
556: struct mbuf *m1 = m;
557: u_char *cp = bpfbuf + SLIP_HDRLEN;
558:
559: len = 0;
560: do {
561: int mlen = m1->m_len;
562:
563: bcopy(mtod(m1, caddr_t), cp, mlen);
564: cp += mlen;
565: len += mlen;
566: } while ((m1 = m1->m_next) != NULL);
567: }
568: #endif
569: if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) {
570: if (sc->sc_if.if_flags & SC_COMPRESS)
571: *mtod(m, u_char *) |= sl_compress_tcp(m, ip,
572: &sc->sc_comp, 1);
573: }
574: #if NBPFILTER > 0
575: if (sc->sc_bpf) {
576: /*
577: * Put the SLIP pseudo-"link header" in place. The
578: * compressed header is now at the beginning of the
579: * mbuf.
580: */
581: bpfbuf[SLX_DIR] = SLIPDIR_OUT;
582: bcopy(mtod(m, caddr_t), &bpfbuf[SLX_CHDR], CHDR_LEN);
583: bpf_tap(sc->sc_bpf, bpfbuf, len + SLIP_HDRLEN,
584: BPF_DIRECTION_OUT);
585: }
586: #endif
587: getmicrotime(&sc->sc_lastpacket);
588:
589: #if !(defined(__NetBSD__) || defined(__OpenBSD__)) /* XXX - cgd */
590: /*
591: * If system is getting low on clists, just flush our
592: * output queue (if the stuff was important, it'll get
593: * retransmitted).
594: */
595: if (cfreecount < CLISTRESERVE + SLMTU) {
596: m_freem(m);
597: sc->sc_if.if_collisions++;
598: continue;
599: }
600: #endif /* !__NetBSD__ */
601: /*
602: * The extra FRAME_END will start up a new packet, and thus
603: * will flush any accumulated garbage. We do this whenever
604: * the line may have been idle for some time.
605: */
606: if (tp->t_outq.c_cc == 0) {
607: ++sc->sc_if.if_obytes;
608: (void) putc(FRAME_END, &tp->t_outq);
609: }
610:
611: while (m) {
612: u_char *ep;
613:
614: cp = mtod(m, u_char *); ep = cp + m->m_len;
615: while (cp < ep) {
616: /*
617: * Find out how many bytes in the string we can
618: * handle without doing something special.
619: */
620: u_char *bp = cp;
621:
622: while (cp < ep) {
623: switch (*cp++) {
624: case FRAME_ESCAPE:
625: case FRAME_END:
626: --cp;
627: goto out;
628: }
629: }
630: out:
631: if (cp > bp) {
632: /*
633: * Put n characters at once
634: * into the tty output queue.
635: */
636: #if defined(__NetBSD__) || defined(__OpenBSD__) /* XXX - cgd */
637: if (b_to_q((u_char *)bp, cp - bp,
638: #else
639: if (b_to_q((char *)bp, cp - bp,
640: #endif
641: &tp->t_outq))
642: break;
643: sc->sc_if.if_obytes += cp - bp;
644: }
645: /*
646: * If there are characters left in the mbuf,
647: * the first one must be special..
648: * Put it out in a different form.
649: */
650: if (cp < ep) {
651: if (putc(FRAME_ESCAPE, &tp->t_outq))
652: break;
653: if (putc(*cp++ == FRAME_ESCAPE ?
654: TRANS_FRAME_ESCAPE : TRANS_FRAME_END,
655: &tp->t_outq)) {
656: (void) unputc(&tp->t_outq);
657: break;
658: }
659: sc->sc_if.if_obytes += 2;
660: }
661: }
662: MFREE(m, m2);
663: m = m2;
664: }
665:
666: if (putc(FRAME_END, &tp->t_outq)) {
667: /*
668: * Not enough room. Remove a char to make room
669: * and end the packet normally.
670: * If you get many collisions (more than one or two
671: * a day) you probably do not have enough clists
672: * and you should increase "nclist" in param.c.
673: */
674: (void) unputc(&tp->t_outq);
675: (void) putc(FRAME_END, &tp->t_outq);
676: sc->sc_if.if_collisions++;
677: } else {
678: ++sc->sc_if.if_obytes;
679: sc->sc_if.if_opackets++;
680: }
681: }
682: }
683:
684: /*
685: * Copy data buffer to mbuf chain; add ifnet pointer.
686: */
687: static struct mbuf *
688: sl_btom(sc, len)
689: struct sl_softc *sc;
690: int len;
691: {
692: struct mbuf *m;
693:
694: /*
695: * Allocate a new input buffer and swap.
696: */
697: m = sc->sc_mbuf;
698: MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA);
699: if (sc->sc_mbuf == NULL) {
700: sc->sc_mbuf = m;
701: return (NULL);
702: }
703: MCLGET(sc->sc_mbuf, M_DONTWAIT);
704: if ((sc->sc_mbuf->m_flags & M_EXT) == 0) {
705: /*
706: * we couldn't get a cluster - if memory's this
707: * low, it's time to start dropping packets.
708: */
709: m_freem(sc->sc_mbuf);
710: sc->sc_mbuf = m;
711: return (NULL);
712: }
713: sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf +
714: sc->sc_mbuf->m_ext.ext_size;
715:
716: m->m_data = sc->sc_pktstart;
717:
718: m->m_len = len;
719: m->m_pkthdr.len = len;
720: m->m_pkthdr.rcvif = &sc->sc_if;
721: return (m);
722: }
723:
724: /*
725: * tty interface receiver interrupt.
726: */
727: void
728: slinput(c, tp)
729: int c;
730: struct tty *tp;
731: {
732: struct sl_softc *sc;
733: struct mbuf *m;
734: int len;
735: int s;
736: #if NBPFILTER > 0
737: u_char chdr[CHDR_LEN];
738: #endif
739:
740: tk_nin++;
741: sc = (struct sl_softc *)tp->t_sc;
742: if (sc == NULL)
743: return;
744: if (c & TTY_ERRORMASK || ((tp->t_state & TS_CARR_ON) == 0 &&
745: (tp->t_cflag & CLOCAL) == 0)) {
746: sc->sc_flags |= SC_ERROR;
747: return;
748: }
749: c &= TTY_CHARMASK;
750:
751: ++sc->sc_if.if_ibytes;
752:
753: if (sc->sc_if.if_flags & IFF_DEBUG) {
754: if (c == ABT_ESC) {
755: /*
756: * If we have a previous abort, see whether
757: * this one is within the time limit.
758: */
759: if (sc->sc_abortcount &&
760: time_second >= sc->sc_starttime + ABT_WINDOW)
761: sc->sc_abortcount = 0;
762: /*
763: * If we see an abort after "idle" time, count it;
764: * record when the first abort escape arrived.
765: */
766: if (time_second >= sc->sc_lasttime + ABT_IDLE) {
767: if (++sc->sc_abortcount == 1)
768: sc->sc_starttime = time_second;
769: if (sc->sc_abortcount >= ABT_COUNT) {
770: slclose(tp);
771: return;
772: }
773: }
774: } else
775: sc->sc_abortcount = 0;
776: sc->sc_lasttime = time_second;
777: }
778:
779: switch (c) {
780:
781: case TRANS_FRAME_ESCAPE:
782: if (sc->sc_escape)
783: c = FRAME_ESCAPE;
784: break;
785:
786: case TRANS_FRAME_END:
787: if (sc->sc_escape)
788: c = FRAME_END;
789: break;
790:
791: case FRAME_ESCAPE:
792: sc->sc_escape = 1;
793: return;
794:
795: case FRAME_END:
796: if(sc->sc_flags & SC_ERROR) {
797: sc->sc_flags &= ~SC_ERROR;
798: goto newpack;
799: }
800: len = sc->sc_mp - sc->sc_pktstart;
801: if (len < 3)
802: /* less than min length packet - ignore */
803: goto newpack;
804:
805: #if NBPFILTER > 0
806: if (sc->sc_bpf) {
807: /*
808: * Save the compressed header, so we
809: * can tack it on later. Note that we
810: * will end up copying garbage in some
811: * cases but this is okay. We remember
812: * where the buffer started so we can
813: * compute the new header length.
814: */
815: bcopy(sc->sc_pktstart, chdr, CHDR_LEN);
816: }
817: #endif
818:
819: if ((c = (*sc->sc_pktstart & 0xf0)) != (IPVERSION << 4)) {
820: if (c & 0x80)
821: c = TYPE_COMPRESSED_TCP;
822: else if (c == TYPE_UNCOMPRESSED_TCP)
823: *sc->sc_pktstart &= 0x4f; /* XXX */
824: /*
825: * We've got something that's not an IP packet.
826: * If compression is enabled, try to decompress it.
827: * Otherwise, if `auto-enable' compression is on and
828: * it's a reasonable packet, decompress it and then
829: * enable compression. Otherwise, drop it.
830: */
831: if (sc->sc_if.if_flags & SC_COMPRESS) {
832: len = sl_uncompress_tcp(&sc->sc_pktstart, len,
833: (u_int)c, &sc->sc_comp);
834: if (len <= 0)
835: goto error;
836: } else if ((sc->sc_if.if_flags & SC_AUTOCOMP) &&
837: c == TYPE_UNCOMPRESSED_TCP && len >= 40) {
838: len = sl_uncompress_tcp(&sc->sc_pktstart, len,
839: (u_int)c, &sc->sc_comp);
840: if (len <= 0)
841: goto error;
842: sc->sc_if.if_flags |= SC_COMPRESS;
843: } else
844: goto error;
845: }
846:
847: m = sl_btom(sc, len);
848: if (m == NULL)
849: goto error;
850:
851: #if NBPFILTER > 0
852: if (sc->sc_bpf) {
853: /*
854: * Put the SLIP pseudo-"link header" in place.
855: * Note this M_PREPEND() should bever fail,
856: * since we know we always have enough space
857: * in the input buffer.
858: */
859: u_char *hp;
860:
861: M_PREPEND(m, SLIP_HDRLEN, M_DONTWAIT);
862: if (m == NULL)
863: goto error;
864:
865: hp = mtod(m, u_char *);
866: hp[SLX_DIR] = SLIPDIR_IN;
867: memcpy(&hp[SLX_CHDR], chdr, CHDR_LEN);
868:
869: s = splnet();
870: bpf_mtap(sc->sc_bpf, m, BPF_DIRECTION_IN);
871: splx(s);
872:
873: m_adj(m, SLIP_HDRLEN);
874: }
875: #endif
876:
877: sc->sc_if.if_ipackets++;
878: getmicrotime(&sc->sc_lastpacket);
879: s = splnet();
880: if (IF_QFULL(&ipintrq)) {
881: IF_DROP(&ipintrq);
882: sc->sc_if.if_ierrors++;
883: sc->sc_if.if_iqdrops++;
884: m_freem(m);
885: if (!ipintrq.ifq_congestion)
886: if_congestion(&ipintrq);
887: } else {
888: IF_ENQUEUE(&ipintrq, m);
889: schednetisr(NETISR_IP);
890: }
891: splx(s);
892: goto newpack;
893: }
894: if (sc->sc_mp < sc->sc_ep) {
895: *sc->sc_mp++ = c;
896: sc->sc_escape = 0;
897: return;
898: }
899:
900: /* can't put lower; would miss an extra frame */
901: sc->sc_flags |= SC_ERROR;
902:
903: error:
904: sc->sc_if.if_ierrors++;
905: newpack:
906: sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf +
907: BUFOFFSET;
908: sc->sc_escape = 0;
909: }
910:
911: /*
912: * Process an ioctl request.
913: */
914: int
915: slioctl(ifp, cmd, data)
916: struct ifnet *ifp;
917: u_long cmd;
918: caddr_t data;
919: {
920: struct sl_softc *sc = ifp->if_softc;
921: struct ifaddr *ifa = (struct ifaddr *)data;
922: struct ifreq *ifr;
923: int s = splnet(), error = 0;
924: struct sl_stats *slsp;
925:
926: switch (cmd) {
927:
928: case SIOCSIFADDR:
929: if (ifa->ifa_addr->sa_family == AF_INET)
930: ifp->if_flags |= IFF_UP;
931: else
932: error = EAFNOSUPPORT;
933: break;
934:
935: case SIOCSIFDSTADDR:
936: if (ifa->ifa_addr->sa_family != AF_INET)
937: error = EAFNOSUPPORT;
938: break;
939:
940: case SIOCADDMULTI:
941: case SIOCDELMULTI:
942: ifr = (struct ifreq *)data;
943: if (ifr == 0) {
944: error = EAFNOSUPPORT; /* XXX */
945: break;
946: }
947: switch (ifr->ifr_addr.sa_family) {
948:
949: #ifdef INET
950: case AF_INET:
951: break;
952: #endif
953:
954: default:
955: error = EAFNOSUPPORT;
956: break;
957: }
958: break;
959:
960: case SIOCGSLSTATS:
961: slsp = &((struct ifslstatsreq *) data)->stats;
962: bzero(slsp, sizeof(*slsp));
963: /* slsp->sl = sc->sc_stats; */
964: slsp->sl.sl_ibytes = sc->sc_if.if_ibytes;
965: slsp->sl.sl_obytes = sc->sc_if.if_obytes;
966: slsp->sl.sl_ipackets = sc->sc_if.if_ipackets;
967: slsp->sl.sl_opackets = sc->sc_if.if_opackets;
968: #ifdef INET
969: slsp->vj.vjs_packets = sc->sc_comp.sls_packets;
970: slsp->vj.vjs_compressed = sc->sc_comp.sls_compressed;
971: slsp->vj.vjs_searches = sc->sc_comp.sls_searches;
972: slsp->vj.vjs_misses = sc->sc_comp.sls_misses;
973: slsp->vj.vjs_uncompressedin = sc->sc_comp.sls_uncompressedin;
974: slsp->vj.vjs_compressedin = sc->sc_comp.sls_compressedin;
975: slsp->vj.vjs_errorin = sc->sc_comp.sls_errorin;
976: slsp->vj.vjs_tossed = sc->sc_comp.sls_tossed;
977: #endif /* INET */
978: break;
979:
980: default:
981: error = EINVAL;
982: }
983: splx(s);
984: return (error);
985: }