Commit | Line | Data |
---|---|---|
59d051cb | 1 | /* @(#)if_sl.c 5.5 (Berkeley) %G% */ |
7c2732d1 | 2 | |
41b6e003 MK |
3 | /* |
4 | * Serial Line interface | |
5 | * | |
6 | * Rick Adams | |
7 | * Center for Seismic Studies | |
8 | * 1300 N 17th Street, Suite 1450 | |
9 | * Arlington, Virginia 22209 | |
10 | * (703)276-7900 | |
11 | * rick@seismo.ARPA | |
12 | * seismo!rick | |
13 | * | |
41b6e003 | 14 | * Pounded on heavily by Chris Torek (chris@mimsy.umd.edu, umcp-cs!chris). |
8011f5df | 15 | * N.B.: this belongs in netinet, not net, the way it stands now. |
7c2732d1 MK |
16 | * Should have a link-layer type designation, but wouldn't be |
17 | * backwards-compatible. | |
41b6e003 MK |
18 | * |
19 | * Converted to 4.3BSD Beta by Chris Torek. | |
8011f5df | 20 | * Other changes made at Berkeley, based in part on code by Kirk Smith. |
41b6e003 MK |
21 | */ |
22 | ||
23 | /* $Header: if_sl.c,v 1.12 85/12/20 21:54:55 chris Exp $ */ | |
24 | /* from if_sl.c,v 1.11 84/10/04 12:54:47 rick Exp */ | |
25 | ||
26 | #include "sl.h" | |
27 | #if NSL > 0 | |
28 | ||
29 | #include "param.h" | |
30 | #include "mbuf.h" | |
31 | #include "buf.h" | |
8011f5df | 32 | #include "dk.h" |
41b6e003 MK |
33 | #include "socket.h" |
34 | #include "ioctl.h" | |
8011f5df | 35 | #include "file.h" |
41b6e003 MK |
36 | #include "tty.h" |
37 | #include "errno.h" | |
38 | ||
8011f5df MK |
39 | #include "if.h" |
40 | #include "netisr.h" | |
41 | #include "route.h" | |
42 | #if INET | |
41b6e003 MK |
43 | #include "../netinet/in.h" |
44 | #include "../netinet/in_systm.h" | |
45 | #include "../netinet/ip.h" | |
46 | #include "../netinet/ip_var.h" | |
8011f5df | 47 | #endif |
41b6e003 MK |
48 | |
49 | #ifdef vax | |
50 | #include "../vax/mtpr.h" | |
51 | #endif vax | |
52 | ||
53 | /* | |
8011f5df MK |
54 | * N.B.: SLMTU is now a hard limit on input packet size. |
55 | * SLMTU must be <= CLBYTES - sizeof(struct ifnet *). | |
41b6e003 MK |
56 | */ |
57 | #define SLMTU 1006 | |
8011f5df MK |
58 | #define SLIP_HIWAT 1000 /* don't start a new packet if HIWAT on queue */ |
59 | #define CLISTRESERVE 1000 /* Can't let clists get too low */ | |
41b6e003 MK |
60 | |
61 | struct sl_softc { | |
62 | struct ifnet sc_if; /* network-visible interface */ | |
63 | short sc_flags; /* see below */ | |
64 | short sc_ilen; /* length of input-packet-so-far */ | |
65 | struct tty *sc_ttyp; /* pointer to tty structure */ | |
66 | char *sc_mp; /* pointer to next available buf char */ | |
8011f5df | 67 | char *sc_buf; /* input buffer */ |
41b6e003 MK |
68 | } sl_softc[NSL]; |
69 | ||
70 | /* flags */ | |
71 | #define SC_ESCAPED 0x0001 /* saw a FRAME_ESCAPE */ | |
72 | #define SC_OACTIVE 0x0002 /* output tty is active */ | |
73 | ||
74 | #define FRAME_END 0300 /* Frame End */ | |
75 | #define FRAME_ESCAPE 0333 /* Frame Esc */ | |
76 | #define TRANS_FRAME_END 0334 /* transposed frame end */ | |
77 | #define TRANS_FRAME_ESCAPE 0335 /* transposed frame esc */ | |
78 | ||
79 | #define t_sc T_LINEP | |
80 | ||
81 | int sloutput(), slioctl(), ttrstrt(); | |
82 | ||
83 | /* | |
84 | * Called from boot code to establish sl interfaces. | |
85 | */ | |
86 | slattach() | |
87 | { | |
88 | register struct sl_softc *sc; | |
89 | register int i = 0; | |
90 | ||
91 | for (sc = sl_softc; i < NSL; sc++) { | |
92 | sc->sc_if.if_name = "sl"; | |
93 | sc->sc_if.if_unit = i++; | |
94 | sc->sc_if.if_mtu = SLMTU; | |
95 | sc->sc_if.if_flags = IFF_POINTOPOINT; | |
96 | sc->sc_if.if_ioctl = slioctl; | |
97 | sc->sc_if.if_output = sloutput; | |
98 | sc->sc_if.if_snd.ifq_maxlen = IFQ_MAXLEN; | |
99 | if_attach(&sc->sc_if); | |
100 | } | |
101 | } | |
102 | ||
103 | /* | |
104 | * Line specific open routine. | |
105 | * Attach the given tty to the first available sl unit. | |
106 | */ | |
8011f5df | 107 | /* ARGSUSED */ |
41b6e003 MK |
108 | slopen(dev, tp) |
109 | dev_t dev; | |
110 | register struct tty *tp; | |
111 | { | |
112 | register struct sl_softc *sc; | |
113 | register int nsl; | |
114 | ||
8011f5df MK |
115 | if (!suser()) |
116 | return (EPERM); | |
117 | if (tp->t_line == SLIPDISC) | |
41b6e003 MK |
118 | return (EBUSY); |
119 | ||
120 | for (nsl = 0, sc = sl_softc; nsl < NSL; nsl++, sc++) | |
121 | if (sc->sc_ttyp == NULL) { | |
122 | sc->sc_flags = 0; | |
123 | sc->sc_ilen = 0; | |
8011f5df MK |
124 | if (slinit(sc) == 0) |
125 | return (ENOBUFS); | |
41b6e003 MK |
126 | tp->t_sc = (caddr_t)sc; |
127 | sc->sc_ttyp = tp; | |
8011f5df | 128 | ttyflush(tp, FREAD | FWRITE); |
41b6e003 MK |
129 | return (0); |
130 | } | |
131 | ||
8011f5df | 132 | return (ENXIO); |
41b6e003 MK |
133 | } |
134 | ||
135 | /* | |
136 | * Line specific close routine. | |
137 | * Detach the tty from the sl unit. | |
138 | * Mimics part of ttyclose(). | |
139 | */ | |
140 | slclose(tp) | |
141 | struct tty *tp; | |
142 | { | |
143 | register struct sl_softc *sc; | |
144 | int s; | |
145 | ||
146 | ttywflush(tp); | |
147 | tp->t_line = 0; | |
148 | s = splimp(); /* paranoid; splnet probably ok */ | |
149 | sc = (struct sl_softc *)tp->t_sc; | |
150 | if (sc != NULL) { | |
151 | if_down(&sc->sc_if); | |
152 | sc->sc_ttyp = NULL; | |
153 | tp->t_sc = NULL; | |
8011f5df MK |
154 | MCLFREE((struct mbuf *)sc->sc_buf); |
155 | sc->sc_buf = 0; | |
41b6e003 MK |
156 | } |
157 | splx(s); | |
158 | } | |
159 | ||
160 | /* | |
161 | * Line specific (tty) ioctl routine. | |
162 | * Provide a way to get the sl unit number. | |
163 | */ | |
8011f5df | 164 | /* ARGSUSED */ |
41b6e003 MK |
165 | sltioctl(tp, cmd, data, flag) |
166 | struct tty *tp; | |
167 | caddr_t data; | |
168 | { | |
169 | ||
170 | if (cmd == TIOCGETD) { | |
171 | *(int *)data = ((struct sl_softc *)tp->t_sc)->sc_if.if_unit; | |
172 | return (0); | |
173 | } | |
174 | return (-1); | |
175 | } | |
176 | ||
177 | /* | |
178 | * Queue a packet. Start transmission if not active. | |
179 | */ | |
180 | sloutput(ifp, m, dst) | |
181 | register struct ifnet *ifp; | |
182 | register struct mbuf *m; | |
183 | struct sockaddr *dst; | |
184 | { | |
185 | register struct sl_softc *sc; | |
186 | int s; | |
187 | ||
188 | /* | |
189 | * `Cannot happen' (see slioctl). Someday we will extend | |
190 | * the line protocol to support other address families. | |
191 | */ | |
192 | if (dst->sa_family != AF_INET) { | |
193 | printf("sl%d: af%d not supported\n", ifp->if_unit, | |
194 | dst->sa_family); | |
195 | m_freem(m); | |
196 | return (EAFNOSUPPORT); | |
197 | } | |
198 | ||
199 | sc = &sl_softc[ifp->if_unit]; | |
200 | if (sc->sc_ttyp == NULL) { | |
201 | m_freem(m); | |
202 | return (ENETDOWN); /* sort of */ | |
203 | } | |
eadd9817 MK |
204 | if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0) { |
205 | m_freem(m); | |
206 | return (EHOSTUNREACH); | |
207 | } | |
41b6e003 MK |
208 | s = splimp(); |
209 | if (IF_QFULL(&ifp->if_snd)) { | |
210 | IF_DROP(&ifp->if_snd); | |
211 | splx(s); | |
212 | m_freem(m); | |
8011f5df | 213 | sc->sc_if.if_oerrors++; |
41b6e003 MK |
214 | return (ENOBUFS); |
215 | } | |
216 | IF_ENQUEUE(&ifp->if_snd, m); | |
217 | if ((sc->sc_flags & SC_OACTIVE) == 0) { | |
218 | splx(s); | |
219 | slstart(sc->sc_ttyp); | |
220 | } else | |
221 | splx(s); | |
222 | return (0); | |
223 | } | |
224 | ||
225 | /* | |
226 | * Start output on interface. Get another datagram | |
227 | * to send from the interface queue and map it to | |
228 | * the interface before starting output. | |
229 | */ | |
230 | slstart(tp) | |
231 | register struct tty *tp; | |
232 | { | |
233 | register struct sl_softc *sc = (struct sl_softc *)tp->t_sc; | |
234 | register struct mbuf *m; | |
8011f5df MK |
235 | register int len; |
236 | register u_char *cp; | |
237 | int flush, nd, np, n, s; | |
238 | struct mbuf *m2; | |
239 | extern int cfreecount; | |
41b6e003 | 240 | |
8011f5df MK |
241 | for (;;) { |
242 | /* | |
243 | * If there is more in the output queue, just send it now. | |
244 | * We are being called in lieu of ttstart and must do what | |
245 | * it would. | |
246 | */ | |
247 | if (tp->t_outq.c_cc > 0) | |
248 | ttstart(tp); | |
249 | if (tp->t_outq.c_cc > SLIP_HIWAT) | |
250 | return; | |
41b6e003 | 251 | |
8011f5df MK |
252 | /* |
253 | * This happens briefly when the line shuts down. | |
254 | */ | |
255 | if (sc == NULL) | |
256 | return; | |
41b6e003 | 257 | |
8011f5df MK |
258 | /* |
259 | * If system is getting low on clists | |
260 | * and we have something running already, stop here. | |
261 | */ | |
262 | if (cfreecount < CLISTRESERVE + SLMTU && | |
263 | sc->sc_flags & SC_OACTIVE) | |
264 | return; | |
41b6e003 | 265 | |
8011f5df MK |
266 | /* |
267 | * Get a packet and send it to the interface. | |
268 | */ | |
269 | s = splimp(); | |
270 | IF_DEQUEUE(&sc->sc_if.if_snd, m); | |
271 | if (m == NULL) { | |
272 | if (tp->t_outq.c_cc == 0) | |
273 | sc->sc_flags &= ~SC_OACTIVE; | |
274 | splx(s); | |
275 | return; | |
41b6e003 | 276 | } |
8011f5df MK |
277 | flush = !(sc->sc_flags & SC_OACTIVE); |
278 | sc->sc_flags |= SC_OACTIVE; | |
279 | splx(s); | |
41b6e003 | 280 | |
41b6e003 | 281 | /* |
8011f5df MK |
282 | * The extra FRAME_END will start up a new packet, and thus |
283 | * will flush any accumulated garbage. We do this whenever | |
284 | * the line may have been idle for some time. | |
41b6e003 | 285 | */ |
8011f5df MK |
286 | if (flush) |
287 | (void) putc(FRAME_END, &tp->t_outq); | |
288 | ||
289 | while (m) { | |
290 | cp = mtod(m, u_char *); | |
291 | len = m->m_len; | |
292 | while (len > 0) { | |
293 | /* | |
294 | * Find out how many bytes in the string we can | |
295 | * handle without doing something special. | |
296 | */ | |
297 | nd = locc(FRAME_ESCAPE, len, cp); | |
298 | np = locc(FRAME_END, len, cp); | |
299 | n = len - MAX(nd, np); | |
300 | if (n) { | |
301 | /* | |
302 | * Put n characters at once | |
303 | * into the tty output queue. | |
304 | */ | |
305 | if (b_to_q((char *)cp, n, &tp->t_outq)) | |
306 | break; | |
59d051cb KM |
307 | len -= n; |
308 | cp += n; | |
8011f5df MK |
309 | } |
310 | /* | |
311 | * If there are characters left in the mbuf, | |
312 | * the first one must be special.. | |
313 | * Put it out in a different form. | |
314 | */ | |
315 | if (len) { | |
316 | if (putc(FRAME_ESCAPE, &tp->t_outq)) | |
317 | break; | |
318 | if (putc(*cp == FRAME_ESCAPE ? | |
319 | TRANS_FRAME_ESCAPE : TRANS_FRAME_END, | |
320 | &tp->t_outq)) { | |
321 | (void) unputc(&tp->t_outq); | |
322 | break; | |
323 | } | |
324 | cp++; | |
325 | len--; | |
326 | } | |
327 | } | |
328 | MFREE(m, m2); | |
329 | m = m2; | |
330 | } | |
41b6e003 | 331 | |
8011f5df MK |
332 | if (putc(FRAME_END, &tp->t_outq)) { |
333 | /* | |
334 | * Not enough room. Remove a char to make room | |
335 | * and end the packet normally. | |
336 | * If you get many collisions (more than one or two | |
337 | * a day) you probably do not have enough clists | |
338 | * and you should increase "nclist" in param.c. | |
339 | */ | |
340 | (void) unputc(&tp->t_outq); | |
341 | (void) putc(FRAME_END, &tp->t_outq); | |
342 | sc->sc_if.if_collisions++; | |
343 | } else | |
344 | sc->sc_if.if_opackets++; | |
345 | } | |
346 | } | |
347 | ||
348 | slinit(sc) | |
349 | register struct sl_softc *sc; | |
350 | { | |
351 | struct mbuf *p; | |
352 | ||
353 | if (sc->sc_buf == (char *) 0) { | |
354 | MCLALLOC(p, 1); | |
355 | if (p) { | |
356 | sc->sc_buf = (char *)p; | |
357 | sc->sc_mp = sc->sc_buf + sizeof(struct ifnet *); | |
358 | } else { | |
359 | printf("sl%d: can't allocate buffer\n", sc - sl_softc); | |
360 | sc->sc_if.if_flags &= ~IFF_UP; | |
361 | return (0); | |
362 | } | |
363 | } | |
364 | return (1); | |
41b6e003 MK |
365 | } |
366 | ||
367 | /* | |
368 | * Copy data buffer to mbuf chain; add ifnet pointer ifp. | |
369 | */ | |
370 | struct mbuf * | |
8011f5df MK |
371 | sl_btom(sc, len, ifp) |
372 | struct sl_softc *sc; | |
41b6e003 MK |
373 | register int len; |
374 | struct ifnet *ifp; | |
375 | { | |
8011f5df | 376 | register caddr_t cp; |
41b6e003 | 377 | register struct mbuf *m, **mp; |
8011f5df | 378 | register unsigned count; |
41b6e003 MK |
379 | struct mbuf *top = NULL; |
380 | ||
8011f5df | 381 | cp = sc->sc_buf + sizeof(struct ifnet *); |
41b6e003 MK |
382 | mp = ⊤ |
383 | while (len > 0) { | |
384 | MGET(m, M_DONTWAIT, MT_DATA); | |
385 | if ((*mp = m) == NULL) { | |
386 | m_freem(top); | |
387 | return (NULL); | |
388 | } | |
8011f5df | 389 | if (ifp) |
41b6e003 | 390 | m->m_off += sizeof(ifp); |
8011f5df MK |
391 | /* |
392 | * If we have at least NBPG bytes, | |
393 | * allocate a new page. Swap the current buffer page | |
394 | * with the new one. We depend on having a space | |
395 | * left at the beginning of the buffer | |
396 | * for the interface pointer. | |
397 | */ | |
398 | if (len >= NBPG) { | |
399 | MCLGET(m); | |
400 | if (m->m_len == CLBYTES) { | |
401 | cp = mtod(m, char *); | |
402 | m->m_off = (int)sc->sc_buf - (int)m; | |
403 | sc->sc_buf = mtod(m, char *); | |
404 | if (ifp) { | |
405 | m->m_off += sizeof(ifp); | |
406 | count = MIN(len, | |
407 | CLBYTES - sizeof(struct ifnet *)); | |
41b6e003 | 408 | } else |
8011f5df MK |
409 | count = MIN(len, CLBYTES); |
410 | goto nocopy; | |
411 | } | |
41b6e003 | 412 | } |
8011f5df MK |
413 | if (ifp) |
414 | count = MIN(len, MLEN - sizeof(ifp)); | |
415 | else | |
416 | count = MIN(len, MLEN); | |
417 | bcopy(cp, mtod(m, caddr_t), count); | |
418 | nocopy: | |
41b6e003 MK |
419 | m->m_len = count; |
420 | if (ifp) { | |
421 | m->m_off -= sizeof(ifp); | |
422 | m->m_len += sizeof(ifp); | |
423 | *mtod(m, struct ifnet **) = ifp; | |
424 | ifp = NULL; | |
425 | } | |
8011f5df | 426 | cp += count; |
41b6e003 MK |
427 | len -= count; |
428 | mp = &m->m_next; | |
429 | } | |
430 | return (top); | |
431 | } | |
432 | ||
433 | /* | |
434 | * tty interface receiver interrupt. | |
435 | */ | |
436 | slinput(c, tp) | |
437 | register int c; | |
438 | register struct tty *tp; | |
439 | { | |
440 | register struct sl_softc *sc; | |
441 | register struct mbuf *m; | |
442 | int s; | |
443 | ||
8011f5df | 444 | tk_nin++; |
41b6e003 MK |
445 | sc = (struct sl_softc *)tp->t_sc; |
446 | if (sc == NULL) | |
447 | return; | |
448 | ||
449 | c &= 0xff; | |
450 | if (sc->sc_flags & SC_ESCAPED) { | |
451 | sc->sc_flags &= ~SC_ESCAPED; | |
452 | switch (c) { | |
453 | ||
454 | case TRANS_FRAME_ESCAPE: | |
455 | c = FRAME_ESCAPE; | |
456 | break; | |
457 | ||
458 | case TRANS_FRAME_END: | |
459 | c = FRAME_END; | |
460 | break; | |
461 | ||
462 | default: | |
463 | sc->sc_if.if_ierrors++; | |
8011f5df | 464 | sc->sc_mp = sc->sc_buf + sizeof(struct ifnet *); |
41b6e003 MK |
465 | sc->sc_ilen = 0; |
466 | return; | |
467 | } | |
468 | } else { | |
469 | switch (c) { | |
470 | ||
471 | case FRAME_END: | |
472 | if (sc->sc_ilen == 0) /* ignore */ | |
473 | return; | |
8011f5df | 474 | m = sl_btom(sc, sc->sc_ilen, &sc->sc_if); |
41b6e003 MK |
475 | if (m == NULL) { |
476 | sc->sc_if.if_ierrors++; | |
477 | return; | |
478 | } | |
8011f5df | 479 | sc->sc_mp = sc->sc_buf + sizeof(struct ifnet *); |
41b6e003 MK |
480 | sc->sc_ilen = 0; |
481 | sc->sc_if.if_ipackets++; | |
482 | s = splimp(); | |
483 | if (IF_QFULL(&ipintrq)) { | |
484 | IF_DROP(&ipintrq); | |
485 | sc->sc_if.if_ierrors++; | |
486 | m_freem(m); | |
487 | } else { | |
488 | IF_ENQUEUE(&ipintrq, m); | |
489 | schednetisr(NETISR_IP); | |
490 | } | |
491 | splx(s); | |
492 | return; | |
493 | ||
494 | case FRAME_ESCAPE: | |
495 | sc->sc_flags |= SC_ESCAPED; | |
496 | return; | |
497 | } | |
498 | } | |
499 | if (++sc->sc_ilen >= SLMTU) { | |
500 | sc->sc_if.if_ierrors++; | |
8011f5df | 501 | sc->sc_mp = sc->sc_buf + sizeof(struct ifnet *); |
41b6e003 MK |
502 | sc->sc_ilen = 0; |
503 | return; | |
504 | } | |
505 | *sc->sc_mp++ = c; | |
506 | } | |
507 | ||
508 | /* | |
509 | * Process an ioctl request. | |
510 | */ | |
511 | slioctl(ifp, cmd, data) | |
512 | register struct ifnet *ifp; | |
513 | int cmd; | |
514 | caddr_t data; | |
515 | { | |
516 | register struct ifaddr *ifa = (struct ifaddr *)data; | |
517 | int s = splimp(), error = 0; | |
518 | ||
519 | switch (cmd) { | |
520 | ||
521 | case SIOCSIFADDR: | |
522 | if (ifa->ifa_addr.sa_family == AF_INET) | |
523 | ifp->if_flags |= IFF_UP; | |
524 | else | |
525 | error = EAFNOSUPPORT; | |
526 | break; | |
527 | ||
528 | case SIOCSIFDSTADDR: | |
529 | if (ifa->ifa_addr.sa_family != AF_INET) | |
530 | error = EAFNOSUPPORT; | |
531 | break; | |
532 | ||
533 | default: | |
534 | error = EINVAL; | |
535 | } | |
536 | splx(s); | |
537 | return (error); | |
538 | } | |
539 | #endif |