xref: /original-bsd/sys/deprecated/netimp/if_imp.c (revision f662c168)
1 /*	if_imp.c	4.17	82/03/19	*/
2 
3 #include "imp.h"
4 #if NIMP > 0
5 /*
6  * ARPAnet IMP interface driver.
7  *
8  * The IMP-host protocol is handled here, leaving
9  * hardware specifics to the lower level interface driver.
10  *
11  * TODO:
12  *	rethink coupling between this module and device driver
13  *	pass more error indications up to protocol modules
14  */
15 #include "../h/param.h"
16 #include "../h/systm.h"
17 #include "../h/mbuf.h"
18 #include "../h/pte.h"
19 #include "../h/buf.h"
20 #include "../h/protosw.h"
21 #include "../h/socket.h"
22 #include "../h/ubareg.h"
23 #include "../h/ubavar.h"
24 #include "../h/cpu.h"
25 #include "../h/mtpr.h"
26 #include "../h/vmmac.h"
27 #include "../net/in.h"
28 #include "../net/in_systm.h"
29 #include "../net/if.h"
30 #include "../net/if_imp.h"
31 #include "../net/if_imphost.h"
32 #include "../net/ip.h"
33 #include "../net/ip_var.h"
34 
35 /*
36  * IMP software status per interface.
37  * (partially shared with the hardware specific module)
38  *
39  * Each interface is referenced by a network interface structure,
40  * imp_if, which the routing code uses to locate the interface.
41  * This structure contains the output queue for the interface, its
42  * address, ...  IMP specific structures used in connecting the
43  * IMP software modules to the hardware specific interface routines
44  * are stored here.  The common structures are made visible to the
45  * interface driver by passing a pointer to the hardware routine
46  * at "attach" time.
47  *
48  * NOTE: imp_if and imp_cb are assumed adjacent in hardware code.
49  */
50 struct imp_softc {
51 	struct	ifnet imp_if;		/* network visible interface */
52 	struct	impcb imp_cb;		/* hooks to hardware module */
53 	u_char	imp_state;		/* current state of IMP */
54 	char	imp_dropcnt;		/* used during initialization */
55 } imp_softc[NIMP];
56 
57 /*
58  * Messages from IMP regarding why
59  * it's going down.
60  */
61 static char *impmessage[] = {
62 	"in 30 seconds",
63 	"for hardware PM",
64 	"to reload software",
65 	"for emergency reset"
66 };
67 
68 int	impdown(), impinit(), impoutput();
69 
70 /*
71  * IMP attach routine.  Called from hardware device attach routine
72  * at configuration time with a pointer to the UNIBUS device structure.
73  * Sets up local state and returns pointer to base of ifnet+impcb
74  * structures.  This is then used by the device's attach routine
75  * set up its back pointers.
76  */
77 impattach(ui)
78 	struct uba_device *ui;
79 {
80 	struct imp_softc *sc = &imp_softc[ui->ui_unit];
81 	register struct ifnet *ifp = &sc->imp_if;
82 
83 COUNT(IMPATTACH);
84 	/* UNIT COULD BE AMBIGUOUS */
85 	ifp->if_unit = ui->ui_unit;
86 	ifp->if_name = "imp";
87 	ifp->if_mtu = IMP_MTU - sizeof (struct imp_leader);
88 	ifp->if_net = ui->ui_flags;
89 	/* the host and imp fields will be filled in by the imp */
90 	ifp->if_addr = if_makeaddr(ifp->if_net, 0);
91 	ifp->if_init = impinit;
92 	ifp->if_output = impoutput;
93 	/* reset is handled at the hardware level */
94 	if_attach(ifp);
95 	/* kludge to hand pointers back to hardware attach routine */
96 	return ((int)&sc->imp_if);
97 }
98 
99 #ifdef notdef
100 /*
101  * Timer routine to keep priming the IMP until it sends
102  * us the noops we need.  Since we depend on the host and
103  * imp values returned in the noop messages, we must wait
104  * for them before we allow any outgoing traffic.
105  */
106 imptimer(sc)
107 	register struct imp_softc *sc;
108 {
109 	int s = splimp();
110 
111 	if (sc->imp_state != IMPS_INIT) {
112 		splx(s);
113 		return;
114 	}
115 	sc->imp_dropcnt = IMP_DROPCNT;
116 	impnoops(sc);
117 	timeout(imptimer, (caddr_t)sc, 30 * hz);
118 	splx(s);
119 }
120 #endif
121 
122 /*
123  * IMP initialization routine: call hardware module to
124  * setup UNIBUS resources, init state and get ready for
125  * NOOPs the IMP should send us, and that we want to drop.
126  */
127 impinit(unit)
128 	int unit;
129 {
130 	register struct imp_softc *sc = &imp_softc[unit];
131 
132 	if ((*sc->imp_cb.ic_init)(unit) == 0) {
133 		sc->imp_state = IMPS_DOWN;
134 		return;
135 	}
136 	sc->imp_state = IMPS_INIT;
137 #ifdef notdef
138 	imptimer(sc);
139 #else
140 	sc->imp_dropcnt = IMP_DROPCNT;
141 	impnoops(sc);
142 #endif
143 }
144 
145 struct sockproto impproto = { PF_IMPLINK };
146 struct sockaddr_in impdst = { AF_IMPLINK };
147 struct sockaddr_in impsrc = { AF_IMPLINK };
148 
149 /*
150  * ARPAnet 1822 input routine.
151  * Called from hardware input interrupt routine to handle 1822
152  * IMP-host messages.  Type 0 messages (non-control) are
153  * passed to higher level protocol processors on the basis
154  * of link number.  Other type messages (control) are handled here.
155  */
156 impinput(unit, m)
157 	int unit;
158 	register struct mbuf *m;
159 {
160 	register struct imp_leader *ip;
161 	register struct imp_softc *sc = &imp_softc[unit];
162 	register struct host *hp;
163 	register struct ifqueue *inq;
164 	struct control_leader *cp;
165 	struct in_addr addr;
166 	struct mbuf *next;
167 
168 COUNT(IMPINPUT);
169 	/* verify leader length. */
170 	if (m->m_len < sizeof(struct control_leader) &&
171 	    (m = m_pullup(m, sizeof(struct control_leader))) == 0)
172 		return;
173 	cp = mtod(m, struct control_leader *);
174 	if (cp->dl_mtype == IMPTYPE_DATA)
175 		if (m->m_len < sizeof(struct imp_leader) &&
176 		    (m = m_pullup(m, sizeof(struct imp_leader))) == 0)
177 			return;
178 	ip = mtod(m, struct imp_leader *);
179 
180 	/* check leader type */
181 	if (ip->il_format != IMP_NFF) {
182 		sc->imp_if.if_collisions++;	/* XXX */
183 		goto drop;
184 	}
185 
186 	/*
187 	 * Certain messages require a host structure.
188 	 * Do this in one shot here.
189 	 */
190 	switch (ip->il_mtype) {
191 
192 	case IMPTYPE_RFNM:
193 	case IMPTYPE_INCOMPLETE:
194 	case IMPTYPE_HOSTDEAD:
195 	case IMPTYPE_HOSTUNREACH:
196 	case IMPTYPE_BADDATA:
197 #ifdef notdef
198 		addr.s_net = ip->il_network;
199 #else
200 		addr.s_net = 0;
201 #endif
202 		addr.s_imp = ip->il_imp;
203 		addr.s_host = ip->il_host;
204 		hp = hostlookup(addr);
205 		break;
206 	}
207 
208 	switch (ip->il_mtype) {
209 
210 	case IMPTYPE_DATA:
211 		break;
212 
213 	/*
214 	 * IMP leader error.  Reset the IMP and discard the packet.
215 	 */
216 	case IMPTYPE_BADLEADER:
217 		/*
218 		 * According to 1822 document, this message
219 		 * will be generated in response to the
220 		 * first noop sent to the IMP after
221 		 * the host resets the IMP interface.
222 		 */
223 		if (sc->imp_state != IMPS_INIT) {
224 			impmsg(sc, "leader error");
225 			hostreset(sc->imp_if.if_net);	/* XXX */
226 			impnoops(sc);
227 		}
228 		goto rawlinkin;
229 
230 	/*
231 	 * IMP going down.  Print message, and if not immediate,
232 	 * set off a timer to insure things will be reset at the
233 	 * appropriate time.
234 	 */
235 	case IMPTYPE_DOWN:
236 		if ((ip->il_link & IMP_DMASK) == 0) {
237 			sc->imp_state = IMPS_GOINGDOWN;
238 			timeout(impdown, (caddr_t)sc, 30 * hz);
239 		}
240 		impmsg(sc, "going down %s",
241 			(u_int)impmessage[ip->il_link&IMP_DMASK]);
242 		goto rawlinkin;
243 
244 	/*
245 	 * A NOP usually seen during the initialization sequence.
246 	 * Compare the local address with that in the message.
247 	 * Reset the local address notion if it doesn't match.
248 	 */
249 	case IMPTYPE_NOOP: {
250 		register struct in_addr *sin;
251 
252 		if (sc->imp_state == IMPS_DOWN) {
253 			sc->imp_state = IMPS_INIT;
254 			sc->imp_dropcnt = IMP_DROPCNT;
255 		}
256 		if (sc->imp_state != IMPS_INIT || --sc->imp_dropcnt > 0)
257 			goto rawlinkin;
258 		sc->imp_state = IMPS_UP;
259 		sin = &sc->imp_if.if_addr;
260 		sc->imp_if.if_host[0] = sin->s_host = ip->il_host;
261 		sin->s_imp = ip->il_imp;
262 		impmsg(sc, "reset (host %d/imp %d)", (u_int)ip->il_host,
263 			ntohs(ip->il_imp));
264 		/* restart output in case something was q'd */
265 		(*sc->imp_cb.ic_start)(sc->imp_if.if_unit);
266 		goto rawlinkin;
267 	}
268 
269 	/*
270 	 * RFNM or INCOMPLETE message, record in
271 	 * host table and prime output routine.
272 	 *
273 	 * SHOULD NOTIFY PROTOCOL ABOUT INCOMPLETES.
274 	 */
275 	case IMPTYPE_RFNM:
276 	case IMPTYPE_INCOMPLETE:
277 		if (hp && hp->h_rfnm)
278 			if (next = hostdeque(hp))
279 				(void) impsnd(&sc->imp_if, next);
280 		goto rawlinkin;
281 
282 	/*
283 	 * Host or IMP can't be reached.  Flush any packets
284 	 * awaiting transmission and release the host structure.
285 	 *
286 	 * TODO: NOTIFY THE PROTOCOL
287 	 */
288 	case IMPTYPE_HOSTDEAD:
289 		impmsg(sc, "host dead");	/* XXX */
290 		goto common;			/* XXX */
291 
292 	/* SHOULD SIGNAL ROUTING DAEMON */
293 	case IMPTYPE_HOSTUNREACH:
294 		impmsg(sc, "host unreachable");	/* XXX */
295 	common:
296 		if (hp)
297 			hostfree(hp);		/* won't work right */
298 		goto rawlinkin;
299 
300 	/*
301 	 * Error in data.  Clear RFNM status for this host and send
302 	 * noops to the IMP to clear the interface.
303 	 */
304 	case IMPTYPE_BADDATA:
305 		impmsg(sc, "data error");
306 		if (hp)
307 			hp->h_rfnm = 0;
308 		impnoops(sc);
309 		goto rawlinkin;
310 
311 	/*
312 	 * Interface reset.
313 	 */
314 	case IMPTYPE_RESET:
315 		impmsg(sc, "interface reset");
316 		impnoops(sc);
317 		goto rawlinkin;
318 
319 	default:
320 		sc->imp_if.if_collisions++;		/* XXX */
321 		goto rawlinkin;
322 	}
323 
324 	/*
325 	 * Data for a protocol.  Dispatch to the appropriate
326 	 * protocol routine (running at software interrupt).
327 	 * If this isn't a raw interface, advance pointer
328 	 * into mbuf past leader.
329 	 */
330 	switch (ip->il_link) {
331 
332 #ifdef INET
333 	case IMPLINK_IP:
334 		m->m_len -= sizeof(struct imp_leader);
335 		m->m_off += sizeof(struct imp_leader);
336 		setipintr();
337 		inq = &ipintrq;
338 		break;
339 #endif
340 
341 	default:
342 	rawlinkin:
343 		impproto.sp_protocol = ip->il_link;
344 		impdst.sin_addr = sc->imp_if.if_addr;
345 		impsrc.sin_addr.s_net = ip->il_network;
346 		impsrc.sin_addr.s_host = ip->il_host;
347 		impsrc.sin_addr.s_imp = ip->il_imp;
348 		raw_input(m, &impproto, (struct sockaddr *)&impdst,
349 		  (struct sockaddr *)&impsrc);
350 		return;
351 	}
352 	if (IF_QFULL(inq)) {
353 		IF_DROP(inq);
354 		goto drop;
355 	}
356 	IF_ENQUEUE(inq, m);
357 	return;
358 
359 drop:
360 	m_freem(m);
361 }
362 
363 /*
364  * Bring the IMP down after notification.
365  */
366 impdown(sc)
367 	struct imp_softc *sc;
368 {
369 
370 	sc->imp_state = IMPS_DOWN;
371 	impmsg(sc, "marked down");
372 	/* notify protocols with messages waiting? */
373 }
374 
375 /*VARARGS*/
376 impmsg(sc, fmt, a1, a2)
377 	struct imp_softc *sc;
378 	char *fmt;
379 	u_int a1;
380 {
381 
382 	printf("imp%d: ", sc->imp_if.if_unit);
383 	printf(fmt, a1, a2);
384 	printf("\n");
385 }
386 
387 /*
388  * ARPAnet 1822 output routine.
389  * Called from higher level protocol routines to set up messages for
390  * transmission to the imp.  Sets up the header and calls impsnd to
391  * enqueue the message for this IMP's hardware driver.
392  */
393 impoutput(ifp, m0, pf)
394 	register struct ifnet *ifp;
395 	struct mbuf *m0;
396 {
397 	register struct imp_leader *imp;
398 	register struct mbuf *m = m0;
399 	int x, dhost, dimp, dlink, len, dnet;
400 
401 COUNT(IMPOUTPUT);
402 	/*
403 	 * Don't even try if the IMP is unavailable.
404 	 */
405 	x = imp_softc[ifp->if_unit].imp_state;
406 	if (x == IMPS_DOWN || x == IMPS_GOINGDOWN)
407 		goto drop;
408 
409 	switch (pf) {
410 
411 #ifdef INET
412 	case PF_INET: {
413 		register struct ip *ip = mtod(m0, struct ip *);
414 
415 		dhost = ip->ip_dst.s_host;
416 		dimp = ip->ip_dst.s_impno;
417 		dlink = IMPLINK_IP;
418 		dnet = 0;
419 		len = ntohs((u_short)ip->ip_len);
420 		break;
421 	}
422 #endif
423 	case PF_IMPLINK:
424 		goto leaderexists;
425 
426 	default:
427 		printf("imp%d: can't encapsulate pf%d\n", ifp->if_unit, pf);
428 		goto drop;
429 	}
430 
431 	/*
432 	 * Add IMP leader.  If there's not enough space in the
433 	 * first mbuf, allocate another.  If that should fail, we
434 	 * drop this sucker.
435 	 */
436 	if (m->m_off > MMAXOFF ||
437 	    MMINOFF + sizeof(struct imp_leader) > m->m_off) {
438 		m = m_get(M_DONTWAIT);
439 		if (m == 0)
440 			goto drop;
441 		m->m_next = m0;
442 		m->m_off = MMINOFF;
443 		m->m_len = sizeof(struct imp_leader);
444 	} else {
445 		m->m_off -= sizeof(struct imp_leader);
446 		m->m_len += sizeof(struct imp_leader);
447 	}
448 	imp = mtod(m, struct imp_leader *);
449 	imp->il_format = IMP_NFF;
450 	imp->il_mtype = IMPTYPE_DATA;
451 	imp->il_network = dnet;
452 	imp->il_host = dhost;
453 	imp->il_imp = htons((u_short)dimp);
454 	imp->il_length =
455 		htons((u_short)(len + sizeof(struct imp_leader)) << 3);
456 	imp->il_link = dlink;
457 	imp->il_flags = imp->il_htype = imp->il_subtype = 0;
458 
459 leaderexists:
460 	/*
461 	 * Hand message to impsnd to perform RFNM counting
462 	 * and eventual transmission.
463 	 */
464 	return (impsnd(ifp, m));
465 drop:
466 	m_freem(m0);
467 	return (0);
468 }
469 
470 /*
471  * Put a message on an interface's output queue.
472  * Perform RFNM counting: no more than 8 message may be
473  * in flight to any one host.
474  */
475 impsnd(ifp, m)
476 	struct ifnet *ifp;
477 	struct mbuf *m;
478 {
479 	register struct imp_leader *ip;
480 	register struct host *hp;
481 	struct impcb *icp;
482 	int x;
483 
484 COUNT(IMPSND);
485 	ip = mtod(m, struct imp_leader *);
486 
487 	/*
488 	 * Do RFNM counting for data messages
489 	 * (no more than 8 outstanding to any host)
490 	 */
491 	x = splimp();
492 	if (ip->il_mtype == IMPTYPE_DATA) {
493 		struct in_addr addr;
494 
495 #ifdef notdef
496                 addr.s_net = ip->il_network;
497 #else
498 		addr.s_net = 0;
499 #endif
500                 addr.s_host = ip->il_host;
501                 addr.s_imp = ip->il_imp;
502 		if ((hp = hostlookup(addr)) == 0)
503 			hp = hostenter(addr);
504 
505 		/*
506 		 * If IMP would block, queue until RFNM
507 		 */
508 		if (hp) {
509 			if (hp->h_rfnm < 8) {
510 				hp->h_rfnm++;
511 				goto enque;
512 			}
513 			if (hp->h_qcnt < 8) {	/* high water mark */
514 				HOST_ENQUE(hp, m);
515 				goto start;
516 			}
517 		}
518 		m_freem(m);
519 		splx(x);
520 		return (0);
521 	}
522 enque:
523 	if (IF_QFULL(&ifp->if_snd)) {
524 		IF_DROP(&ifp->if_snd);
525 		m_freem(m);
526 		splx(x);
527 		return (0);
528 	}
529 	IF_ENQUEUE(&ifp->if_snd, m);
530 start:
531 	splx(x);
532 	icp = &imp_softc[ifp->if_unit].imp_cb;
533 	if (icp->ic_oactive == 0)
534 		(*icp->ic_start)(ifp->if_unit);
535 	return (1);
536 }
537 
538 /*
539  * Put three 1822 NOOPs at the head of the output queue.
540  * Part of host-IMP initialization procedure.
541  * (Should return success/failure, but noone knows
542  * what to do with this, so why bother?)
543  */
544 impnoops(sc)
545 	register struct imp_softc *sc;
546 {
547 	register i;
548 	register struct mbuf *m;
549 	register struct control_leader *cp;
550 	int x;
551 
552 COUNT(IMPNOOPS);
553 	sc->imp_state = IMPS_INIT;
554 	sc->imp_dropcnt = IMP_DROPCNT;
555 	for (i = 0; i < IMP_DROPCNT + 1; i++ ) {
556 		if ((m = m_getclr(M_DONTWAIT)) == 0)
557 			return;
558 		m->m_off = MMINOFF;
559 		m->m_len = sizeof(struct control_leader);
560 		cp = mtod(m, struct control_leader *);
561 		cp->dl_format = IMP_NFF;
562                 cp->dl_link = i;
563                 cp->dl_mtype = IMPTYPE_NOOP;
564 		x = splimp();
565 		IF_PREPEND(&sc->imp_if.if_snd, m);
566 		splx(x);
567 	}
568 	if (sc->imp_cb.ic_oactive == 0)
569 		(*sc->imp_cb.ic_start)(sc->imp_if.if_unit);
570 }
571 
572 #ifdef IMPLEADERS
573 printleader(routine, ip)
574 	char *routine;
575 	register struct imp_leader *ip;
576 {
577 	printf("%s: ", routine);
578 	printbyte((char *)ip, 12);
579 	printf("<fmt=%x,net=%x,flags=%x,mtype=", ip->il_format, ip->il_network,
580 		ip->il_flags);
581 	if (ip->il_mtype <= IMPTYPE_READY)
582 		printf("%s,", impleaders[ip->il_mtype]);
583 	else
584 		printf("%x,", ip->il_mtype);
585 	printf("htype=%x,host=%x,imp=%x,link=", ip->il_htype, ip->il_host,
586 		ntohs(ip->il_imp));
587 	if (ip->il_link == IMPLINK_IP)
588 		printf("ip,");
589 	else
590 		printf("%x,", ip->il_link);
591 	printf("subtype=%x,len=%x>\n",ip->il_subtype,ntohs(ip->il_length)>>3);
592 }
593 
594 printbyte(cp, n)
595 	register char *cp;
596 	int n;
597 {
598 	register i, j, c;
599 
600 	for (i=0; i<n; i++) {
601 		c = *cp++;
602 		for (j=0; j<2; j++)
603 			putchar("0123456789abcdef"[(c>>((1-j)*4))&0xf]);
604 		putchar(' ');
605 	}
606 	putchar('\n');
607 }
608 #endif
609 #endif
610