1 /*	if_imp.c	4.36	82/06/15	*/
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 #include "../h/param.h"
12 #include "../h/systm.h"
13 #include "../h/mbuf.h"
14 #include "../h/pte.h"
15 #include "../h/buf.h"
16 #include "../h/protosw.h"
17 #include "../h/socket.h"
18 #include "../h/ubareg.h"
19 #include "../h/ubavar.h"
20 #include "../h/cpu.h"
21 #include "../h/mtpr.h"
22 #include "../h/vmmac.h"
23 #include "../net/in.h"
24 #include "../net/in_systm.h"
25 #include "../net/if.h"
26 /* define IMPLEADERS here to get leader printing code */
27 #include "../net/if_imp.h"
28 #include "../net/if_imphost.h"
29 #include "../net/ip.h"
30 #include "../net/ip_var.h"
31 #include "../net/route.h"
32 #include <errno.h>
33 
34 /*
35  * IMP software status per interface.
36  * (partially shared with the hardware specific module)
37  *
38  * Each interface is referenced by a network interface structure,
39  * imp_if, which the routing code uses to locate the interface.
40  * This structure contains the output queue for the interface, its
41  * address, ...  IMP specific structures used in connecting the
42  * IMP software modules to the hardware specific interface routines
43  * are stored here.  The common structures are made visible to the
44  * interface driver by passing a pointer to the hardware routine
45  * at "attach" time.
46  *
47  * NOTE: imp_if and imp_cb are assumed adjacent in hardware code.
48  */
49 struct imp_softc {
50 	struct	ifnet imp_if;		/* network visible interface */
51 	struct	impcb imp_cb;		/* hooks to hardware module */
52 	u_char	imp_state;		/* current state of IMP */
53 	char	imp_dropcnt;		/* used during initialization */
54 } imp_softc[NIMP];
55 
56 /*
57  * Messages from IMP regarding why
58  * it's going down.
59  */
60 static char *impmessage[] = {
61 	"in 30 seconds",
62 	"for hardware PM",
63 	"to reload software",
64 	"for emergency reset"
65 };
66 
67 int	impdown(), impinit(), impoutput();
68 
69 /*
70  * IMP attach routine.  Called from hardware device attach routine
71  * at configuration time with a pointer to the UNIBUS device structure.
72  * Sets up local state and returns pointer to base of ifnet+impcb
73  * structures.  This is then used by the device's attach routine
74  * set up its back pointers.
75  */
76 impattach(ui)
77 	struct uba_device *ui;
78 {
79 	struct imp_softc *sc = &imp_softc[ui->ui_unit];
80 	register struct ifnet *ifp = &sc->imp_if;
81 	struct sockaddr_in *sin;
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 = IMPMTU - 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 	sin = (struct sockaddr_in *)&ifp->if_addr;
91 	sin->sin_family = AF_INET;
92 	sin->sin_addr = if_makeaddr(ifp->if_net, 0);
93 	ifp->if_init = impinit;
94 	ifp->if_output = impoutput;
95 	/* reset is handled at the hardware level */
96 	if_attach(ifp);
97 	return ((int)&sc->imp_if);
98 }
99 
100 /*
101  * IMP initialization routine: call hardware module to
102  * setup UNIBUS resources, init state and get ready for
103  * NOOPs the IMP should send us, and that we want to drop.
104  */
105 impinit(unit)
106 	int unit;
107 {
108 	int s = splimp();
109 	register struct imp_softc *sc = &imp_softc[unit];
110 
111 COUNT(IMPINIT);
112 	if ((*sc->imp_cb.ic_init)(unit) == 0) {
113 		sc->imp_state = IMPS_DOWN;
114 		sc->imp_if.if_flags &= ~IFF_UP;
115 		splx(s);
116 		return;
117 	}
118 	sc->imp_state = IMPS_INIT;
119 	impnoops(sc);
120 	splx(s);
121 }
122 
123 struct sockproto impproto = { PF_IMPLINK };
124 struct sockaddr_in impdst = { AF_IMPLINK };
125 struct sockaddr_in impsrc = { AF_IMPLINK };
126 #ifdef IMPLEADERS
127 int	impprintfs = 0;
128 #endif
129 
130 /*
131  * ARPAnet 1822 input routine.
132  * Called from hardware input interrupt routine to handle 1822
133  * IMP-host messages.  Type 0 messages (non-control) are
134  * passed to higher level protocol processors on the basis
135  * of link number.  Other type messages (control) are handled here.
136  */
137 impinput(unit, m)
138 	int unit;
139 	register struct mbuf *m;
140 {
141 	register struct imp_leader *ip;
142 	register struct imp_softc *sc = &imp_softc[unit];
143 	register struct host *hp;
144 	register struct ifqueue *inq;
145 	struct control_leader *cp;
146 	struct in_addr addr;
147 	struct mbuf *next;
148 	struct sockaddr_in *sin;
149 
150 COUNT(IMPINPUT);
151 	/* verify leader length. */
152 	if (m->m_len < sizeof(struct control_leader) &&
153 	    (m = m_pullup(m, sizeof(struct control_leader))) == 0)
154 		return;
155 	cp = mtod(m, struct control_leader *);
156 	if (cp->dl_mtype == IMPTYPE_DATA)
157 		if (m->m_len < sizeof(struct imp_leader) &&
158 		    (m = m_pullup(m, sizeof(struct imp_leader))) == 0)
159 			return;
160 	ip = mtod(m, struct imp_leader *);
161 #ifdef IMPLEADERS
162 	if (impprintfs)
163 		printleader("impinput", ip);
164 #endif
165 
166 	/* check leader type */
167 	if (ip->il_format != IMP_NFF) {
168 		sc->imp_if.if_collisions++;	/* XXX */
169 		goto drop;
170 	}
171 
172 	if (ip->il_mtype != IMPTYPE_DATA) {
173 #ifdef notdef
174 		addr.s_net = ip->il_network;
175 #else
176 		addr.s_net = sc->imp_if.if_net;
177 #endif
178 		addr.s_imp = ip->il_imp;
179 		addr.s_host = ip->il_host;
180 	}
181 	switch (ip->il_mtype) {
182 
183 	case IMPTYPE_DATA:
184 		break;
185 
186 	/*
187 	 * IMP leader error.  Reset the IMP and discard the packet.
188 	 */
189 	case IMPTYPE_BADLEADER:
190 		/*
191 		 * According to 1822 document, this message
192 		 * will be generated in response to the
193 		 * first noop sent to the IMP after
194 		 * the host resets the IMP interface.
195 		 */
196 		if (sc->imp_state != IMPS_INIT) {
197 			impmsg(sc, "leader error");
198 			hostreset(sc->imp_if.if_net);
199 			impnoops(sc);
200 		}
201 		goto drop;
202 
203 	/*
204 	 * IMP going down.  Print message, and if not immediate,
205 	 * set off a timer to insure things will be reset at the
206 	 * appropriate time.
207 	 */
208 	case IMPTYPE_DOWN:
209 		if (sc->imp_state < IMPS_INIT)
210 			goto drop;
211 		if ((ip->il_link & IMP_DMASK) == 0) {
212 			sc->imp_state = IMPS_GOINGDOWN;
213 			timeout(impdown, (caddr_t)sc, 30 * hz);
214 		}
215 		impmsg(sc, "going down %s",
216 			(u_int)impmessage[ip->il_link&IMP_DMASK]);
217 		goto drop;
218 
219 	/*
220 	 * A NOP usually seen during the initialization sequence.
221 	 * Compare the local address with that in the message.
222 	 * Reset the local address notion if it doesn't match.
223 	 */
224 	case IMPTYPE_NOOP:
225 		if (sc->imp_state == IMPS_DOWN) {
226 			sc->imp_state = IMPS_INIT;
227 			sc->imp_dropcnt = IMP_DROPCNT;
228 		}
229 		if (sc->imp_state == IMPS_INIT && --sc->imp_dropcnt > 0)
230 			goto drop;
231 		sin = (struct sockaddr_in *)&sc->imp_if.if_addr;
232 		if (sin->sin_addr.s_host != ip->il_host ||
233 		    sin->sin_addr.s_imp != ip->il_imp) {
234 			sc->imp_if.if_host[0] =
235 				sin->sin_addr.s_host = ip->il_host;
236 			sin->sin_addr.s_imp = ip->il_imp;
237 			impmsg(sc, "reset (host %d/imp %d)", (u_int)ip->il_host,
238 				ntohs(ip->il_imp));
239 		}
240 		sc->imp_state = IMPS_UP;
241 		sc->imp_if.if_flags |= IFF_UP;
242 		if_rtinit(&sc->imp_if, RTF_UP);
243 		goto drop;
244 
245 	/*
246 	 * RFNM or INCOMPLETE message, send next
247 	 * message on the q.  We could pass incomplete's
248 	 * up to the next level, but this currently isn't
249 	 * needed.
250 	 */
251 	case IMPTYPE_RFNM:
252 	case IMPTYPE_INCOMPLETE:
253 		if (hp = hostlookup(addr)) {
254 			if (hp->h_rfnm == 0)
255 				hp->h_flags &= ~HF_INUSE;
256 			else if (next = hostdeque(hp))
257 				(void) impsnd(&sc->imp_if, next);
258 		}
259 		goto drop;
260 
261 	/*
262 	 * Host or IMP can't be reached.  Flush any packets
263 	 * awaiting transmission and release the host structure.
264 	 */
265 	case IMPTYPE_HOSTDEAD:
266 	case IMPTYPE_HOSTUNREACH: {
267 		int s = splnet();
268 		impnotify(ip->il_mtype, ip, hostlookup(addr));
269 		splx(s);
270 		goto rawlinkin;
271 	}
272 
273 	/*
274 	 * Error in data.  Clear RFNM status for this host and send
275 	 * noops to the IMP to clear the interface.
276 	 */
277 	case IMPTYPE_BADDATA: {
278 		int s;
279 
280 		impmsg(sc, "data error");
281 		s = splnet();
282 		if (hp = hostlookup(addr))
283 			hp->h_rfnm = 0;
284 		splx(s);
285 		impnoops(sc);
286 		goto drop;
287 	}
288 
289 	/*
290 	 * Interface reset.
291 	 */
292 	case IMPTYPE_RESET:
293 		impmsg(sc, "interface reset");
294 		impnoops(sc);
295 		goto drop;
296 
297 	default:
298 		sc->imp_if.if_collisions++;		/* XXX */
299 		goto drop;
300 	}
301 
302 	/*
303 	 * Data for a protocol.  Dispatch to the appropriate
304 	 * protocol routine (running at software interrupt).
305 	 * If this isn't a raw interface, advance pointer
306 	 * into mbuf past leader.
307 	 */
308 	switch (ip->il_link) {
309 
310 #ifdef INET
311 	case IMPLINK_IP:
312 		m->m_len -= sizeof(struct imp_leader);
313 		m->m_off += sizeof(struct imp_leader);
314 		schednetisr(NETISR_IP);
315 		inq = &ipintrq;
316 		break;
317 #endif
318 
319 	default:
320 	rawlinkin:
321 		impproto.sp_protocol = ip->il_link;
322 		sin = (struct sockaddr_in *)&sc->imp_if.if_addr;
323 		impdst.sin_addr = sin->sin_addr;;
324 		impsrc.sin_addr.s_net = ip->il_network;
325 		impsrc.sin_addr.s_host = ip->il_host;
326 		impsrc.sin_addr.s_imp = ip->il_imp;
327 		raw_input(m, &impproto, (struct sockaddr *)&impsrc,
328 		  (struct sockaddr *)&impdst);
329 		return;
330 	}
331 	if (IF_QFULL(inq)) {
332 		IF_DROP(inq);
333 		goto drop;
334 	}
335 	IF_ENQUEUE(inq, m);
336 	return;
337 
338 drop:
339 	m_freem(m);
340 }
341 
342 /*
343  * Bring the IMP down after notification.
344  */
345 impdown(sc)
346 	struct imp_softc *sc;
347 {
348 
349 COUNT(IMPDOWN);
350 	sc->imp_state = IMPS_DOWN;
351 	impmsg(sc, "marked down");
352 	hostreset(sc->imp_if.if_net);
353 	if_down(&sc->imp_if);
354 }
355 
356 /*VARARGS*/
357 impmsg(sc, fmt, a1, a2)
358 	struct imp_softc *sc;
359 	char *fmt;
360 	u_int a1;
361 {
362 
363 COUNT(IMPMSG);
364 	printf("imp%d: ", sc->imp_if.if_unit);
365 	printf(fmt, a1, a2);
366 	printf("\n");
367 }
368 
369 /*
370  * Process an IMP "error" message, passing this
371  * up to the higher level protocol.
372  */
373 impnotify(what, cp, hp)
374 	int what;
375 	struct control_leader *cp;
376 	struct host *hp;
377 {
378 	struct in_addr in;
379 
380 COUNT(IMPNOTIFY);
381 #ifdef notdef
382 	in.s_net = cp->dl_network;
383 #else
384 	in.s_net = 10;			/* XXX */
385 #endif
386 	in.s_host = cp->dl_host;
387 	in.s_imp = cp->dl_imp;
388 	if (cp->dl_link != IMPLINK_IP)
389 		raw_ctlinput(what, (caddr_t)&in);
390 	else
391 		ip_ctlinput(what, (caddr_t)&in);
392 	if (hp) {
393 		hp->h_flags |= (1 << what);
394 		hostfree(hp);
395 	}
396 }
397 
398 /*
399  * ARPAnet 1822 output routine.
400  * Called from higher level protocol routines to set up messages for
401  * transmission to the imp.  Sets up the header and calls impsnd to
402  * enqueue the message for this IMP's hardware driver.
403  */
404 impoutput(ifp, m0, dst)
405 	register struct ifnet *ifp;
406 	struct mbuf *m0;
407 	struct sockaddr *dst;
408 {
409 	register struct imp_leader *imp;
410 	register struct mbuf *m = m0;
411 	int x, dhost, dimp, dlink, len, dnet;
412 	int error = 0;
413 
414 COUNT(IMPOUTPUT);
415 	/*
416 	 * Don't even try if the IMP is unavailable.
417 	 */
418 	if (imp_softc[ifp->if_unit].imp_state != IMPS_UP) {
419 		error = ENETDOWN;
420 		goto drop;
421 	}
422 
423 	switch (dst->sa_family) {
424 
425 #ifdef INET
426 	case AF_INET: {
427 		struct ip *ip = mtod(m0, struct ip *);
428 		struct sockaddr_in *sin = (struct sockaddr_in *)dst;
429 
430 		dhost = sin->sin_addr.s_host;
431 		dimp = sin->sin_addr.s_impno;
432 		dlink = IMPLINK_IP;
433 		dnet = 0;
434 		len = ntohs((u_short)ip->ip_len);
435 		break;
436 	}
437 #endif
438 	case AF_IMPLINK:
439 		goto leaderexists;
440 
441 	default:
442 		printf("imp%d: can't handle af%d\n", ifp->if_unit,
443 			dst->sa_family);
444 		error = EAFNOSUPPORT;
445 		goto drop;
446 	}
447 
448 	/*
449 	 * Add IMP leader.  If there's not enough space in the
450 	 * first mbuf, allocate another.  If that should fail, we
451 	 * drop this sucker.
452 	 */
453 	if (m->m_off > MMAXOFF ||
454 	    MMINOFF + sizeof(struct imp_leader) > m->m_off) {
455 		m = m_get(M_DONTWAIT);
456 		if (m == 0) {
457 			error = ENOBUFS;
458 			goto drop;
459 		}
460 		m->m_next = m0;
461 		m->m_off = MMINOFF;
462 		m->m_len = sizeof(struct imp_leader);
463 	} else {
464 		m->m_off -= sizeof(struct imp_leader);
465 		m->m_len += sizeof(struct imp_leader);
466 	}
467 	imp = mtod(m, struct imp_leader *);
468 	imp->il_format = IMP_NFF;
469 	imp->il_mtype = IMPTYPE_DATA;
470 	imp->il_network = dnet;
471 	imp->il_host = dhost;
472 	imp->il_imp = htons((u_short)dimp);
473 	imp->il_length =
474 		htons((u_short)(len + sizeof(struct imp_leader)) << 3);
475 	imp->il_link = dlink;
476 	imp->il_flags = imp->il_htype = imp->il_subtype = 0;
477 
478 leaderexists:
479 	return (impsnd(ifp, m));
480 drop:
481 	m_freem(m0);
482 	return (error);
483 }
484 
485 /*
486  * Put a message on an interface's output queue.
487  * Perform RFNM counting: no more than 8 message may be
488  * in flight to any one host.
489  */
490 impsnd(ifp, m)
491 	struct ifnet *ifp;
492 	struct mbuf *m;
493 {
494 	register struct imp_leader *ip;
495 	register struct host *hp;
496 	struct impcb *icp;
497 	int s, error;
498 
499 COUNT(IMPSND);
500 	ip = mtod(m, struct imp_leader *);
501 
502 	/*
503 	 * Do RFNM counting for data messages
504 	 * (no more than 8 outstanding to any host)
505 	 */
506 	s = splimp();
507 	if (ip->il_mtype == IMPTYPE_DATA) {
508 		struct in_addr addr;
509 
510 #ifdef notdef
511                 addr.s_net = ip->il_network;
512 #else
513 		addr.s_net = ifp->if_net;	/* XXX */
514 #endif
515                 addr.s_host = ip->il_host;
516                 addr.s_imp = ip->il_imp;
517 		if ((hp = hostlookup(addr)) == 0)
518 			hp = hostenter(addr);
519 		if (hp && (hp->h_flags & (HF_DEAD|HF_UNREACH))) {
520 			error = hp->h_flags&HF_DEAD ? EHOSTDOWN : EHOSTUNREACH;
521 			hp->h_timer = HOSTTIMER;
522 			hp->h_flags &= ~HF_INUSE;
523 			goto bad;
524 		}
525 
526 		/*
527 		 * If IMP would block, queue until RFNM
528 		 */
529 		if (hp) {
530 			if (hp->h_rfnm < 8) {
531 				hp->h_rfnm++;
532 				goto enque;
533 			}
534 			if (hp->h_qcnt < 8) {	/* high water mark */
535 				HOST_ENQUE(hp, m);
536 				goto start;
537 			}
538 		}
539 		error = ENOBUFS;
540 		goto bad;
541 	}
542 enque:
543 	if (IF_QFULL(&ifp->if_snd)) {
544 		IF_DROP(&ifp->if_snd);
545 		error = ENOBUFS;
546 bad:
547 		m_freem(m);
548 		splx(s);
549 		return (error);
550 	}
551 	IF_ENQUEUE(&ifp->if_snd, m);
552 start:
553 	icp = &imp_softc[ifp->if_unit].imp_cb;
554 	if (icp->ic_oactive == 0)
555 		(*icp->ic_start)(ifp->if_unit);
556 	splx(s);
557 	return (0);
558 }
559 
560 /*
561  * Put three 1822 NOOPs at the head of the output queue.
562  * Part of host-IMP initialization procedure.
563  * (Should return success/failure, but noone knows
564  * what to do with this, so why bother?)
565  * This routine is always called at splimp, so we don't
566  * protect the call to IF_PREPEND.
567  */
568 impnoops(sc)
569 	register struct imp_softc *sc;
570 {
571 	register i;
572 	register struct mbuf *m;
573 	register struct control_leader *cp;
574 	int x;
575 
576 COUNT(IMPNOOPS);
577 	sc->imp_dropcnt = IMP_DROPCNT;
578 	for (i = 0; i < IMP_DROPCNT + 1; i++ ) {
579 		if ((m = m_getclr(M_DONTWAIT)) == 0)
580 			return;
581 		m->m_off = MMINOFF;
582 		m->m_len = sizeof(struct control_leader);
583 		cp = mtod(m, struct control_leader *);
584 		cp->dl_format = IMP_NFF;
585                 cp->dl_link = i;
586                 cp->dl_mtype = IMPTYPE_NOOP;
587 		IF_PREPEND(&sc->imp_if.if_snd, m);
588 	}
589 	if (sc->imp_cb.ic_oactive == 0)
590 		(*sc->imp_cb.ic_start)(sc->imp_if.if_unit);
591 }
592 
593 #ifdef IMPLEADERS
594 printleader(routine, ip)
595 	char *routine;
596 	register struct imp_leader *ip;
597 {
598 	printf("%s: ", routine);
599 	printbyte((char *)ip, 12);
600 	printf("<fmt=%x,net=%x,flags=%x,mtype=", ip->il_format, ip->il_network,
601 		ip->il_flags);
602 	if (ip->il_mtype <= IMPTYPE_READY)
603 		printf("%s,", impleaders[ip->il_mtype]);
604 	else
605 		printf("%x,", ip->il_mtype);
606 	printf("htype=%x,host=%x,imp=%x,link=", ip->il_htype, ip->il_host,
607 		ntohs(ip->il_imp));
608 	if (ip->il_link == IMPLINK_IP)
609 		printf("ip,");
610 	else
611 		printf("%x,", ip->il_link);
612 	printf("subtype=%x,len=%x>\n",ip->il_subtype,ntohs(ip->il_length)>>3);
613 }
614 
615 printbyte(cp, n)
616 	register char *cp;
617 	int n;
618 {
619 	register i, j, c;
620 
621 	for (i=0; i<n; i++) {
622 		c = *cp++;
623 		for (j=0; j<2; j++)
624 			putchar("0123456789abcdef"[(c>>((1-j)*4))&0xf]);
625 		putchar(' ');
626 	}
627 	putchar('\n');
628 }
629 #endif
630 #endif
631