2 * ppp_tty.c - Point-to-Point Protocol (PPP) driver for asynchronous
5 * Copyright (c) 1989 Carnegie Mellon University.
8 * Redistribution and use in source and binary forms are permitted
9 * provided that the above copyright notice and this paragraph are
10 * duplicated in all such forms and that any documentation,
11 * advertising materials, and other materials related to such
12 * distribution and use acknowledge that the software was developed
13 * by Carnegie Mellon University. The name of the
14 * University may not be used to endorse or promote products derived
15 * from this software without specific prior written permission.
16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
18 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
21 * Carnegie Mellon University
23 * Pittsburgh, PA 15213
28 * @(#)if_sl.c 7.6.1.2 (Berkeley) 2/15/89
30 * Copyright (c) 1987 Regents of the University of California.
31 * All rights reserved.
33 * Redistribution and use in source and binary forms are permitted
34 * provided that the above copyright notice and this paragraph are
35 * duplicated in all such forms and that any documentation,
36 * advertising materials, and other materials related to such
37 * distribution and use acknowledge that the software was developed
38 * by the University of California, Berkeley. The name of the
39 * University may not be used to endorse or promote products derived
40 * from this software without specific prior written permission.
41 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
42 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
43 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
45 * Serial Line interface
48 * Center for Seismic Studies
49 * 1300 N 17th Street, Suite 1450
50 * Arlington, Virginia 22209
55 * Pounded on heavily by Chris Torek (chris@mimsy.umd.edu, umcp-cs!chris).
56 * Converted to 4.3BSD Beta by Chris Torek.
57 * Other changes made at Berkeley, based in part on code by Kirk Smith.
59 * Converted to 4.3BSD+ 386BSD by Brad Parker (brad@cayman.com)
60 * Added VJ tcp header compression; more unified ioctls
62 * Extensively modified by Paul Mackerras (paulus@cs.anu.edu.au).
63 * Cleaned up a lot of the mbuf-related code to fix bugs that
64 * caused system crashes and packet corruption. Changed pppstart
65 * so that it doesn't just give up with a "collision" if the whole
66 * packet doesn't fit in the output ring buffer.
68 * Added priority queueing for interactive IP packets, following
69 * the model of if_sl.c, plus hooks for bpf.
70 * Paul Mackerras (paulus@cs.anu.edu.au).
73 /* $FreeBSD: src/sys/net/ppp_tty.c,v 1.43.2.1 2002/02/13 00:43:11 dillon Exp $ */
74 /* $DragonFly: src/sys/net/ppp_layer/ppp_tty.c,v 1.25 2008/05/14 11:59:23 sephe Exp $ */
76 #include "opt_ppp.h" /* XXX for ppp_defs.h */
78 #define VJC /* XXX for ppp_defs.h */
80 #include <sys/param.h>
81 #include <sys/systm.h>
84 #include <sys/dkstat.h>
85 #include <sys/socket.h>
86 #include <sys/fcntl.h>
87 #include <sys/thread2.h>
91 #include <sys/vnode.h>
94 #include <net/ifq_var.h>
99 #include <net/ppp/if_ppp.h>
100 #include <net/ppp/if_pppvar.h>
102 static int pppopen (cdev_t dev, struct tty *tp);
103 static int pppclose (struct tty *tp, int flag);
104 static int pppread (struct tty *tp, struct uio *uio, int flag);
105 static int pppwrite (struct tty *tp, struct uio *uio, int flag);
106 static int ppptioctl (struct tty *tp, u_long cmd, caddr_t data,
107 int flag, struct ucred *);
108 static int pppinput (int c, struct tty *tp);
109 static int pppstart (struct tty *tp);
111 static u_short pppfcs (u_short fcs, u_char *cp, int len);
112 static void pppasyncstart (struct ppp_softc *);
113 static void pppasyncctlp (struct ppp_softc *);
114 static void pppasyncrelinq (struct ppp_softc *);
115 static void pppasyncsetmtu (struct ppp_softc *);
116 static void ppp_timeout (void *);
117 static void pppgetm (struct ppp_softc *sc);
118 static void ppplogchar (struct ppp_softc *, int);
120 /* XXX called from if_ppp.c - layering violation */
121 void pppasyncattach (void *);
124 * Some useful mbuf macros not in mbuf.h.
126 #define M_IS_CLUSTER(m) ((m)->m_flags & M_EXT)
128 #define M_DATASTART(m) \
129 (M_IS_CLUSTER(m) ? (m)->m_ext.ext_buf : \
130 (m)->m_flags & M_PKTHDR ? (m)->m_pktdat : (m)->m_dat)
132 #define M_DATASIZE(m) \
133 (M_IS_CLUSTER(m) ? (m)->m_ext.ext_size : \
134 (m)->m_flags & M_PKTHDR ? MHLEN: MLEN)
137 * Does c need to be escaped?
139 #define ESCAPE_P(c) (sc->sc_asyncmap[(c) >> 5] & (1 << ((c) & 0x1F)))
142 * Procedures for using an async tty interface for PPP.
145 /* This is a FreeBSD-2.X kernel. */
146 #define CCOUNT(q) ((q)->c_cc)
147 #define PPP_LOWAT 100 /* Process more output when < LOWAT on queue */
148 #define PPP_HIWAT 400 /* Don't start a new packet if HIWAT on que */
151 * Define the PPP line discipline.
154 static struct linesw pppdisc = {
155 pppopen, pppclose, pppread, pppwrite,
156 ppptioctl, pppinput, pppstart, ttymodem,
161 pppasyncattach(void *dummy)
163 /* register line discipline */
164 linesw[PPPDISC] = pppdisc;
168 * Line specific open routine for async tty devices.
169 * Attach the given tty to the first available ppp unit.
170 * Called from device open routine or ttioctl() at >= splsofttty()
174 pppopen(cdev_t dev, struct tty *tp)
176 struct thread *td = curthread; /* XXX */
177 struct ppp_softc *sc;
180 if ((error = suser(td)) != 0)
185 if (tp->t_line == PPPDISC) {
186 sc = (struct ppp_softc *) tp->t_sc;
187 if (sc != NULL && sc->sc_devp == (void *) tp) {
193 if ((sc = pppalloc(td)) == NULL) {
199 (*sc->sc_relinq)(sc); /* get previous owner to relinquish the unit */
203 bzero(sc->sc_asyncmap, sizeof(sc->sc_asyncmap));
204 sc->sc_asyncmap[0] = 0xffffffff;
205 sc->sc_asyncmap[3] = 0x60000000;
206 sc->sc_rasyncmap = 0;
207 sc->sc_devp = (void *) tp;
208 sc->sc_start = pppasyncstart;
209 sc->sc_ctlp = pppasyncctlp;
210 sc->sc_relinq = pppasyncrelinq;
211 sc->sc_setmtu = pppasyncsetmtu;
214 sc->sc_if.if_flags |= IFF_RUNNING;
215 getmicrotime(&sc->sc_if.if_lastchange);
216 sc->sc_if.if_baudrate = tp->t_ospeed;
218 tp->t_sc = (caddr_t) sc;
219 ttyflush(tp, FREAD | FWRITE);
222 * Pre-allocate cblocks to the "just right" amount. The 1 byte t_canq
223 * allocation helps avoid the need for select and/or FIONREAD.
224 * We also pass 1 byte tokens through t_canq...
226 clist_alloc_cblocks(&tp->t_canq, 1, 1);
227 clist_alloc_cblocks(&tp->t_outq, sc->sc_if.if_mtu + PPP_HIWAT,
228 sc->sc_if.if_mtu + PPP_HIWAT);
229 clist_alloc_cblocks(&tp->t_rawq, 0, 0);
237 * Line specific close routine, called from device close routine
238 * and from ttioctl at >= splsofttty().
239 * Detach the tty from the ppp unit.
240 * Mimics part of ttyclose().
243 pppclose(struct tty *tp, int flag)
245 struct ppp_softc *sc;
248 ttyflush(tp, FREAD | FWRITE);
249 clist_free_cblocks(&tp->t_canq);
250 clist_free_cblocks(&tp->t_outq);
252 sc = (struct ppp_softc *) tp->t_sc;
255 if (tp == (struct tty *) sc->sc_devp) {
265 * Relinquish the interface unit to another device.
268 pppasyncrelinq(struct ppp_softc *sc)
273 m_freem(sc->sc_outm);
280 if (sc->sc_flags & SC_TIMEOUT) {
281 callout_stop(&sc->sc_timeout);
282 sc->sc_flags &= ~SC_TIMEOUT;
289 * This gets called from the upper layer to notify a mtu change
292 pppasyncsetmtu(struct ppp_softc *sc)
294 struct tty *tp = (struct tty *) sc->sc_devp;
298 clist_alloc_cblocks(&tp->t_outq, sc->sc_if.if_mtu + PPP_HIWAT,
299 sc->sc_if.if_mtu + PPP_HIWAT);
304 * Line specific (tty) read routine.
305 * called at zero spl from the device driver in the response to user-level
306 * reads on the tty file descriptor (ie: pppd).
309 pppread(struct tty *tp, struct uio *uio, int flag)
311 struct ppp_softc *sc = (struct ppp_softc *)tp->t_sc;
318 * Loop waiting for input, checking that nothing disasterous
319 * happens in the meantime.
323 if (tp != (struct tty *) sc->sc_devp || tp->t_line != PPPDISC) {
327 if (sc->sc_inq.ifq_head != NULL)
329 if ((tp->t_state & TS_CONNECTED) == 0) {
331 return 0; /* end of file */
333 if (tp->t_state & TS_ASYNC || flag & IO_NDELAY) {
335 return (EWOULDBLOCK);
337 error = ttysleep(tp, TSA_HUP_OR_INPUT(tp), PCATCH, "pppin", 0);
344 /* Pull place-holder byte out of canonical queue */
345 clist_getc(&tp->t_canq);
347 /* Get the packet from the input queue */
348 IF_DEQUEUE(&sc->sc_inq, m0);
351 for (m = m0; m && uio->uio_resid; m = m->m_next)
352 if ((error = uiomove(mtod(m, u_char *), m->m_len, uio)) != 0)
359 * Line specific (tty) write routine.
360 * called at zero spl from the device driver in the response to user-level
361 * writes on the tty file descriptor (ie: pppd).
364 pppwrite(struct tty *tp, struct uio *uio, int flag)
366 struct ppp_softc *sc = (struct ppp_softc *)tp->t_sc;
367 struct mbuf *m, *m0, **mp;
371 if ((tp->t_state & TS_CONNECTED) == 0)
372 return 0; /* wrote 0 bytes */
373 if (tp->t_line != PPPDISC)
375 if (sc == NULL || tp != (struct tty *) sc->sc_devp)
377 if (uio->uio_resid > sc->sc_if.if_mtu + PPP_HDRLEN ||
378 uio->uio_resid < PPP_HDRLEN)
382 for (mp = &m0; uio->uio_resid; mp = &m->m_next) {
384 MGETHDR(m, MB_WAIT, MT_DATA);
385 m->m_pkthdr.len = uio->uio_resid - PPP_HDRLEN;
386 m->m_pkthdr.rcvif = NULL;
388 MGET(m, MB_WAIT, MT_DATA);
390 if ((*mp = m) == NULL) {
396 if (uio->uio_resid >= MCLBYTES / 2)
397 MCLGET(m, MB_DONTWAIT);
398 len = M_TRAILINGSPACE(m);
399 if (len > uio->uio_resid)
400 len = uio->uio_resid;
401 if ((error = uiomove(mtod(m, u_char *), len, uio)) != 0) {
408 dst.sa_family = AF_UNSPEC;
409 bcopy(mtod(m0, u_char *), dst.sa_data, PPP_HDRLEN);
410 m0->m_data += PPP_HDRLEN;
411 m0->m_len -= PPP_HDRLEN;
413 /* call the upper layer to "transmit" it... */
414 error = pppoutput(&sc->sc_if, m0, &dst, (struct rtentry *)0);
420 * Line specific (tty) ioctl routine.
421 * This discipline requires that tty device drivers call
422 * the line specific l_ioctl routine from their ioctl routines.
426 ppptioctl(struct tty *tp, u_long cmd, caddr_t data, int flag, struct ucred *cr)
428 struct ppp_softc *sc = (struct ppp_softc *) tp->t_sc;
431 if (sc == NULL || tp != (struct tty *) sc->sc_devp)
436 case PPPIOCSASYNCMAP:
437 if ((error = suser_cred(cr, 0)) != 0)
439 sc->sc_asyncmap[0] = *(u_int *)data;
442 case PPPIOCGASYNCMAP:
443 *(u_int *)data = sc->sc_asyncmap[0];
446 case PPPIOCSRASYNCMAP:
447 if ((error = suser_cred(cr, 0)) != 0)
449 sc->sc_rasyncmap = *(u_int *)data;
452 case PPPIOCGRASYNCMAP:
453 *(u_int *)data = sc->sc_rasyncmap;
456 case PPPIOCSXASYNCMAP:
457 if ((error = suser_cred(cr, 0)) != 0)
460 bcopy(data, sc->sc_asyncmap, sizeof(sc->sc_asyncmap));
461 sc->sc_asyncmap[1] = 0; /* mustn't escape 0x20 - 0x3f */
462 sc->sc_asyncmap[2] &= ~0x40000000; /* mustn't escape 0x5e */
463 sc->sc_asyncmap[3] |= 0x60000000; /* must escape 0x7d, 0x7e */
467 case PPPIOCGXASYNCMAP:
468 bcopy(sc->sc_asyncmap, data, sizeof(sc->sc_asyncmap));
472 error = pppioctl(sc, cmd, data, flag, cr);
473 if (error == 0 && cmd == PPPIOCSMRU)
481 * FCS lookup table as calculated by genfcstab.
483 static u_short fcstab[256] = {
484 0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
485 0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
486 0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
487 0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876,
488 0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd,
489 0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5,
490 0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c,
491 0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974,
492 0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb,
493 0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3,
494 0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a,
495 0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72,
496 0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9,
497 0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1,
498 0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738,
499 0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70,
500 0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7,
501 0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff,
502 0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036,
503 0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e,
504 0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5,
505 0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd,
506 0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134,
507 0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c,
508 0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3,
509 0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb,
510 0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232,
511 0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a,
512 0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1,
513 0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9,
514 0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
515 0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78
519 * Calculate a new FCS given the current FCS and the new data.
522 pppfcs(u_short fcs, u_char *cp, int len)
525 fcs = PPP_FCS(fcs, *cp++);
530 * This gets called at splsoftnet from if_ppp.c at various times
531 * when there is data ready to be sent.
534 pppasyncstart(struct ppp_softc *sc)
536 struct tty *tp = (struct tty *) sc->sc_devp;
539 u_char *start, *stop, *cp;
540 int n, ndone, done, idle;
543 /* XXX assumes atomic access to *tp although we're not at spltty(). */
544 while (CCOUNT(&tp->t_outq) < PPP_HIWAT) {
546 * See if we have an existing packet partly sent.
547 * If not, get a new packet and start sending it.
552 * Get another packet to be sent.
561 * The extra PPP_FLAG will start up a new packet, and thus
562 * will flush any accumulated garbage. We do this whenever
563 * the line may have been idle for some time.
566 if (CCOUNT(&tp->t_outq) == 0) {
567 ++sc->sc_stats.ppp_obytes;
568 clist_putc(PPP_FLAG, &tp->t_outq);
571 /* Calculate the FCS for the first mbuf's worth. */
572 sc->sc_outfcs = pppfcs(PPP_INITFCS, mtod(m, u_char *), m->m_len);
573 getmicrotime(&sc->sc_if.if_lastchange);
577 start = mtod(m, u_char *);
582 * Find out how many bytes in the string we can
583 * handle without doing something special.
585 for (cp = start; cp < stop; cp++)
590 /* NetBSD (0.9 or later), 4.3-Reno or similar. */
591 ndone = n - b_to_q(start, n, &tp->t_outq);
594 sc->sc_stats.ppp_obytes += ndone;
597 break; /* packet doesn't fit */
600 * If there are characters left in the mbuf,
601 * the first one must be special.
602 * Put it out in a different form.
606 if (clist_putc(PPP_ESCAPE, &tp->t_outq)) {
610 if (clist_putc(*start ^ PPP_TRANS, &tp->t_outq)) {
611 clist_unputc(&tp->t_outq);
616 sc->sc_stats.ppp_obytes += 2;
623 * If we didn't empty this mbuf, remember where we're up to.
624 * If we emptied the last mbuf, try to add the FCS and closing
625 * flag, and if we can't, leave sc_outm pointing to m, but with
626 * m->m_len == 0, to remind us to output the FCS and flag later.
629 if (done && m->m_next == NULL) {
635 * We may have to escape the bytes in the FCS.
638 c = ~sc->sc_outfcs & 0xFF;
641 *p++ = c ^ PPP_TRANS;
644 c = (~sc->sc_outfcs >> 8) & 0xFF;
647 *p++ = c ^ PPP_TRANS;
653 * Try to output the FCS and flag. If the bytes
654 * don't all fit, back out.
657 for (q = endseq; q < p; ++q)
658 if (clist_putc(*q, &tp->t_outq)) {
660 for (; q > endseq; --q)
661 clist_unputc(&tp->t_outq);
666 sc->sc_stats.ppp_obytes += q - endseq;
670 /* remember where we got to */
676 /* Finished with this mbuf; free it and move on. */
679 /* Finished a packet */
682 sc->sc_outfcs = pppfcs(sc->sc_outfcs, mtod(m, u_char *), m->m_len);
686 * If m == NULL, we have finished a packet.
687 * If m != NULL, we've either done as much work this time
688 * as we need to, or else we've filled up the output queue.
695 /* Call pppstart to start output again if necessary. */
700 * This timeout is needed for operation on a pseudo-tty,
701 * because the pty code doesn't call pppstart after it has
702 * drained the t_outq.
704 if (!idle && (sc->sc_flags & SC_TIMEOUT) == 0) {
705 callout_reset(&sc->sc_timeout, 1, ppp_timeout, sc);
706 sc->sc_flags |= SC_TIMEOUT;
713 * This gets called when a received packet is placed on
714 * the inq, at splsoftnet. The pppd daemon is to be woken up to do a read().
717 pppasyncctlp(struct ppp_softc *sc)
721 /* Put a placeholder byte in canq for ttselect()/ttnread(). */
723 tp = (struct tty *) sc->sc_devp;
724 clist_putc(0, &tp->t_canq);
730 * Start output on async tty interface. If the transmit queue
731 * has drained sufficiently, arrange for pppasyncstart to be
732 * called later at splsoftnet.
733 * Called at spltty or higher.
736 pppstart(struct tty *tp)
738 struct ppp_softc *sc = (struct ppp_softc *) tp->t_sc;
741 * Call output process whether or not there is any output.
742 * We are being called in lieu of ttstart and must do what it would.
744 if (tp->t_oproc != NULL)
748 * If ALTQ is enabled, don't invoke NETISR_PPP.
749 * pppintr() could loop without doing anything useful
750 * under rate-limiting.
752 if (ifq_is_enabled(&sc->sc_if.if_snd))
756 * If the transmit queue has drained and the tty has not hung up
757 * or been disconnected from the ppp unit, then tell if_ppp.c that
758 * we need more output.
760 if (CCOUNT(&tp->t_outq) < PPP_LOWAT
761 && !((tp->t_state & TS_CONNECTED) == 0)
762 && sc != NULL && tp == (struct tty *) sc->sc_devp) {
770 * Timeout routine - try to start some more output.
775 struct ppp_softc *sc = (struct ppp_softc *) x;
776 struct tty *tp = (struct tty *) sc->sc_devp;
779 sc->sc_flags &= ~SC_TIMEOUT;
785 * Allocate enough mbuf to handle current MRU.
788 pppgetm(struct ppp_softc *sc)
790 struct mbuf *m, **mp;
794 for (len = sc->sc_mru + PPP_HDRLEN + PPP_FCSLEN; len > 0; ){
795 if ((m = *mp) == NULL) {
796 MGETHDR(m, MB_DONTWAIT, MT_DATA);
800 MCLGET(m, MB_DONTWAIT);
802 len -= M_DATASIZE(m);
808 * tty interface receiver interrupt.
810 static unsigned paritytab[8] = {
811 0x96696996, 0x69969669, 0x69969669, 0x96696996,
812 0x69969669, 0x96696996, 0x96696996, 0x69969669
816 * Called when character is available from device driver.
817 * Only guaranteed to be at splsofttty() or spltty()
818 * This is safe to be called while the upper half's netisr is preempted.
821 pppinput(int c, struct tty *tp)
823 struct ppp_softc *sc;
827 sc = (struct ppp_softc *) tp->t_sc;
828 if (sc == NULL || tp != (struct tty *) sc->sc_devp)
832 ++sc->sc_stats.ppp_ibytes;
834 if ((tp->t_state & TS_CONNECTED) == 0) {
835 if (sc->sc_flags & SC_DEBUG)
836 kprintf("%s: no carrier\n", sc->sc_if.if_xname);
840 if (c & TTY_ERRORMASK) {
841 /* framing error or overrun on this char - abort packet */
842 if (sc->sc_flags & SC_DEBUG)
843 kprintf("%s: line error %x\n", sc->sc_if.if_xname,
851 * Handle software flow control of output.
853 if (tp->t_iflag & IXON) {
854 if (c == tp->t_cc[VSTOP] && tp->t_cc[VSTOP] != _POSIX_VDISABLE) {
855 if ((tp->t_state & TS_TTSTOP) == 0) {
856 tp->t_state |= TS_TTSTOP;
861 if (c == tp->t_cc[VSTART] && tp->t_cc[VSTART] != _POSIX_VDISABLE) {
862 tp->t_state &= ~TS_TTSTOP;
863 if (tp->t_oproc != NULL)
871 sc->sc_flags |= SC_RCV_B7_1;
873 sc->sc_flags |= SC_RCV_B7_0;
874 if (paritytab[c >> 5] & (1 << (c & 0x1F)))
875 sc->sc_flags |= SC_RCV_ODDP;
877 sc->sc_flags |= SC_RCV_EVNP;
880 if (sc->sc_flags & SC_LOG_RAWIN)
887 if (sc->sc_rawin_count > 0)
891 * If SC_ESCAPED is set, then we've seen the packet
892 * abort sequence "}~".
894 if (sc->sc_flags & (SC_FLUSH | SC_ESCAPED)
895 || (ilen > 0 && sc->sc_fcs != PPP_GOODFCS)) {
897 sc->sc_flags |= SC_PKTLOST; /* note the dropped packet */
898 if ((sc->sc_flags & (SC_FLUSH | SC_ESCAPED)) == 0){
899 if (sc->sc_flags & SC_DEBUG)
900 kprintf("%s: bad fcs %x, pkt len %d\n",
901 sc->sc_if.if_xname, sc->sc_fcs, ilen);
902 sc->sc_if.if_ierrors++;
903 sc->sc_stats.ppp_ierrors++;
905 sc->sc_flags &= ~(SC_FLUSH | SC_ESCAPED);
910 if (ilen < PPP_HDRLEN + PPP_FCSLEN) {
912 if (sc->sc_flags & SC_DEBUG)
913 kprintf("%s: too short (%d)\n", sc->sc_if.if_xname, ilen);
915 sc->sc_if.if_ierrors++;
916 sc->sc_stats.ppp_ierrors++;
917 sc->sc_flags |= SC_PKTLOST;
924 * Remove FCS trailer. Somewhat painful...
927 if (--sc->sc_mc->m_len == 0) {
928 for (m = sc->sc_m; m->m_next != sc->sc_mc; m = m->m_next)
934 /* excise this mbuf chain */
936 sc->sc_m = sc->sc_mc->m_next;
937 sc->sc_mc->m_next = NULL;
939 ppppktin(sc, m, sc->sc_flags & SC_PKTLOST);
940 if (sc->sc_flags & SC_PKTLOST) {
942 sc->sc_flags &= ~SC_PKTLOST;
950 if (sc->sc_flags & SC_FLUSH) {
951 if (sc->sc_flags & SC_LOG_FLUSH)
956 if (c < 0x20 && (sc->sc_rasyncmap & (1 << c)))
960 if (sc->sc_flags & SC_ESCAPED) {
961 sc->sc_flags &= ~SC_ESCAPED;
963 } else if (c == PPP_ESCAPE) {
964 sc->sc_flags |= SC_ESCAPED;
971 * Initialize buffer on first octet received.
972 * First octet could be address or protocol (when compressing
974 * Second octet is control.
975 * Third octet is first or second (when compressing protocol)
977 * Fourth octet is second octet of protocol.
979 if (sc->sc_ilen == 0) {
980 /* reset the first input mbuf */
981 if (sc->sc_m == NULL) {
983 if (sc->sc_m == NULL) {
984 if (sc->sc_flags & SC_DEBUG)
985 kprintf("%s: no input mbufs!\n", sc->sc_if.if_xname);
991 m->m_data = M_DATASTART(sc->sc_m);
993 sc->sc_mp = mtod(m, char *);
994 sc->sc_fcs = PPP_INITFCS;
995 if (c != PPP_ALLSTATIONS) {
996 if (sc->sc_flags & SC_REJ_COMP_AC) {
997 if (sc->sc_flags & SC_DEBUG)
998 kprintf("%s: garbage received: 0x%x (need 0xFF)\n",
999 sc->sc_if.if_xname, c);
1002 *sc->sc_mp++ = PPP_ALLSTATIONS;
1003 *sc->sc_mp++ = PPP_UI;
1008 if (sc->sc_ilen == 1 && c != PPP_UI) {
1009 if (sc->sc_flags & SC_DEBUG)
1010 kprintf("%s: missing UI (0x3), got 0x%x\n",
1011 sc->sc_if.if_xname, c);
1014 if (sc->sc_ilen == 2 && (c & 1) == 1) {
1015 /* a compressed protocol */
1020 if (sc->sc_ilen == 3 && (c & 1) == 0) {
1021 if (sc->sc_flags & SC_DEBUG)
1022 kprintf("%s: bad protocol %x\n", sc->sc_if.if_xname,
1023 (sc->sc_mp[-1] << 8) + c);
1027 /* packet beyond configured mru? */
1028 if (++sc->sc_ilen > sc->sc_mru + PPP_HDRLEN + PPP_FCSLEN) {
1029 if (sc->sc_flags & SC_DEBUG)
1030 kprintf("%s: packet too big\n", sc->sc_if.if_xname);
1034 /* is this mbuf full? */
1036 if (M_TRAILINGSPACE(m) <= 0) {
1037 if (m->m_next == NULL) {
1039 if (m->m_next == NULL) {
1040 if (sc->sc_flags & SC_DEBUG)
1041 kprintf("%s: too few input mbufs!\n", sc->sc_if.if_xname);
1045 sc->sc_mc = m = m->m_next;
1047 m->m_data = M_DATASTART(m);
1048 sc->sc_mp = mtod(m, char *);
1053 sc->sc_fcs = PPP_FCS(sc->sc_fcs, c);
1057 if (!(sc->sc_flags & SC_FLUSH)) {
1059 sc->sc_if.if_ierrors++;
1060 sc->sc_stats.ppp_ierrors++;
1061 sc->sc_flags |= SC_FLUSH;
1063 if (sc->sc_flags & SC_LOG_FLUSH)
1069 #define MAX_DUMP_BYTES 128
1072 ppplogchar(struct ppp_softc *sc, int c)
1075 sc->sc_rawin[sc->sc_rawin_count++] = c;
1076 if (sc->sc_rawin_count >= sizeof(sc->sc_rawin)
1077 || (c < 0 && sc->sc_rawin_count > 0)) {
1078 kprintf("%s input: %*D", sc->sc_if.if_xname,
1079 sc->sc_rawin_count, sc->sc_rawin, " ");
1080 sc->sc_rawin_count = 0;