1 /*	if_imp.c	4.23	82/04/10	*/
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  *	pass more error indications up to protocol modules
13  */
14 #include "../h/param.h"
15 #include "../h/systm.h"
16 #include "../h/mbuf.h"
17 #include "../h/pte.h"
18 #include "../h/buf.h"
19 #include "../h/protosw.h"
20 #include "../h/socket.h"
21 #include "../h/ubareg.h"
22 #include "../h/ubavar.h"
23 #include "../h/cpu.h"
24 #include "../h/mtpr.h"
25 #include "../h/vmmac.h"
26 #include "../net/in.h"
27 #include "../net/in_systm.h"
28 #include "../net/if.h"
29 #include "../net/if_imp.h"
30 #include "../net/if_imphost.h"
31 #include "../net/ip.h"
32 #include "../net/ip_var.h"
33 #include "../net/route.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 	struct sockaddr_in *sin;
83 
84 COUNT(IMPATTACH);
85 	/* UNIT COULD BE AMBIGUOUS */
86 	ifp->if_unit = ui->ui_unit;
87 	ifp->if_name = "imp";
88 	ifp->if_mtu = IMPMTU - sizeof(struct imp_leader);
89 	ifp->if_net = ui->ui_flags;
90 	/* the host and imp fields will be filled in by the imp */
91 	sin = (struct sockaddr_in *)&ifp->if_addr;
92 	sin->sin_family = AF_INET;
93 	sin->sin_addr = if_makeaddr(ifp->if_net, 0);
94 	ifp->if_init = impinit;
95 	ifp->if_output = impoutput;
96 	/* reset is handled at the hardware level */
97 	if_attach(ifp);
98 	return ((int)&sc->imp_if);
99 }
100 
101 /*
102  * IMP initialization routine: call hardware module to
103  * setup UNIBUS resources, init state and get ready for
104  * NOOPs the IMP should send us, and that we want to drop.
105  */
106 impinit(unit)
107 	int unit;
108 {
109 	int s = splimp();
110 	register struct imp_softc *sc = &imp_softc[unit];
111 
112 COUNT(IMPINIT);
113 	if ((*sc->imp_cb.ic_init)(unit) == 0) {
114 		sc->imp_state = IMPS_DOWN;
115 		sc->imp_if.if_flags &= ~IFF_UP;
116 		splx(s);
117 		return;
118 	}
119 	sc->imp_state = IMPS_INIT;
120 	impnoops(sc);
121 	if_rtinit(&sc->imp_if, RTF_DIRECT|RTF_UP);
122 	splx(s);
123 }
124 
125 struct sockproto impproto = { PF_IMPLINK };
126 struct sockaddr_in impdst = { AF_IMPLINK };
127 struct sockaddr_in impsrc = { AF_IMPLINK };
128 
129 /*
130  * ARPAnet 1822 input routine.
131  * Called from hardware input interrupt routine to handle 1822
132  * IMP-host messages.  Type 0 messages (non-control) are
133  * passed to higher level protocol processors on the basis
134  * of link number.  Other type messages (control) are handled here.
135  */
136 impinput(unit, m)
137 	int unit;
138 	register struct mbuf *m;
139 {
140 	register struct imp_leader *ip;
141 	register struct imp_softc *sc = &imp_softc[unit];
142 	register struct host *hp;
143 	register struct ifqueue *inq;
144 	struct control_leader *cp;
145 	struct in_addr addr;
146 	struct mbuf *next;
147 	struct sockaddr_in *sin;
148 
149 COUNT(IMPINPUT);
150 	/* verify leader length. */
151 	if (m->m_len < sizeof(struct control_leader) &&
152 	    (m = m_pullup(m, sizeof(struct control_leader))) == 0)
153 		return;
154 	cp = mtod(m, struct control_leader *);
155 	if (cp->dl_mtype == IMPTYPE_DATA)
156 		if (m->m_len < sizeof(struct imp_leader) &&
157 		    (m = m_pullup(m, sizeof(struct imp_leader))) == 0)
158 			return;
159 	ip = mtod(m, struct imp_leader *);
160 
161 	/* check leader type */
162 	if (ip->il_format != IMP_NFF) {
163 		sc->imp_if.if_collisions++;	/* XXX */
164 		goto drop;
165 	}
166 
167 	/*
168 	 * Certain messages require a host structure.
169 	 * Do this in one shot here.
170 	 */
171 	switch (ip->il_mtype) {
172 
173 	case IMPTYPE_RFNM:
174 	case IMPTYPE_INCOMPLETE:
175 	case IMPTYPE_HOSTDEAD:
176 	case IMPTYPE_HOSTUNREACH:
177 	case IMPTYPE_BADDATA:
178 #ifdef notdef
179 		addr.s_net = ip->il_network;
180 #else
181 		addr.s_net = 0;
182 #endif
183 		addr.s_imp = ip->il_imp;
184 		addr.s_host = ip->il_host;
185 		hp = hostlookup(addr);
186 		break;
187 	}
188 
189 	switch (ip->il_mtype) {
190 
191 	case IMPTYPE_DATA:
192 		break;
193 
194 	/*
195 	 * IMP leader error.  Reset the IMP and discard the packet.
196 	 */
197 	case IMPTYPE_BADLEADER:
198 		/*
199 		 * According to 1822 document, this message
200 		 * will be generated in response to the
201 		 * first noop sent to the IMP after
202 		 * the host resets the IMP interface.
203 		 */
204 		if (sc->imp_state != IMPS_INIT) {
205 			impmsg(sc, "leader error");
206 			hostreset(sc->imp_if.if_net);	/* XXX */
207 			impnoops(sc);
208 		}
209 		goto rawlinkin;
210 
211 	/*
212 	 * IMP going down.  Print message, and if not immediate,
213 	 * set off a timer to insure things will be reset at the
214 	 * appropriate time.
215 	 */
216 	case IMPTYPE_DOWN:
217 		if ((ip->il_link & IMP_DMASK) == 0) {
218 			sc->imp_state = IMPS_GOINGDOWN;
219 			timeout(impdown, (caddr_t)sc, 30 * hz);
220 		}
221 		impmsg(sc, "going down %s",
222 			(u_int)impmessage[ip->il_link&IMP_DMASK]);
223 		goto rawlinkin;
224 
225 	/*
226 	 * A NOP usually seen during the initialization sequence.
227 	 * Compare the local address with that in the message.
228 	 * Reset the local address notion if it doesn't match.
229 	 */
230 	case IMPTYPE_NOOP:
231 		if (sc->imp_state == IMPS_DOWN) {
232 			sc->imp_state = IMPS_INIT;
233 			sc->imp_dropcnt = IMP_DROPCNT;
234 		}
235 		if (sc->imp_state == IMPS_INIT && --sc->imp_dropcnt > 0)
236 			goto drop;
237 		sin = (struct sockaddr_in *)&sc->imp_if.if_addr;
238 		if (sin->sin_addr.s_host != ip->il_host ||
239 		    sin->sin_addr.s_imp != ip->il_imp) {
240 			sc->imp_if.if_host[0] =
241 				sin->sin_addr.s_host = ip->il_host;
242 			sin->sin_addr.s_imp = ip->il_imp;
243 			impmsg(sc, "reset (host %d/imp %d)", (u_int)ip->il_host,
244 				ntohs(ip->il_imp));
245 		}
246 		sc->imp_state = IMPS_UP;
247 		sc->imp_if.if_flags |= IFF_UP;
248 		/* restart output in case something was q'd */
249 		(*sc->imp_cb.ic_start)(sc->imp_if.if_unit);
250 		goto drop;
251 
252 	/*
253 	 * RFNM or INCOMPLETE message, record in
254 	 * host table and prime output routine.
255 	 *
256 	 * SHOULD NOTIFY PROTOCOL ABOUT INCOMPLETES.
257 	 */
258 	case IMPTYPE_RFNM:
259 	case IMPTYPE_INCOMPLETE:
260 		if (hp && hp->h_rfnm)
261 			if (next = hostdeque(hp))
262 				(void) impsnd(&sc->imp_if, next);
263 		goto drop;
264 
265 	/*
266 	 * Host or IMP can't be reached.  Flush any packets
267 	 * awaiting transmission and release the host structure.
268 	 *
269 	 * TODO: NOTIFY THE PROTOCOL
270 	 */
271 	case IMPTYPE_HOSTDEAD:
272 		impmsg(sc, "host dead");	/* XXX */
273 		goto common;			/* XXX */
274 
275 	/* SHOULD SIGNAL ROUTING DAEMON */
276 	case IMPTYPE_HOSTUNREACH:
277 		impmsg(sc, "host unreachable");	/* XXX */
278 	common:
279 		if (hp)
280 			hostfree(hp);		/* won't work right */
281 		goto rawlinkin;
282 
283 	/*
284 	 * Error in data.  Clear RFNM status for this host and send
285 	 * noops to the IMP to clear the interface.
286 	 */
287 	case IMPTYPE_BADDATA:
288 		impmsg(sc, "data error");
289 		if (hp)
290 			hp->h_rfnm = 0;
291 		impnoops(sc);
292 		goto rawlinkin;
293 
294 	/*
295 	 * Interface reset.
296 	 */
297 	case IMPTYPE_RESET:
298 		impmsg(sc, "interface reset");
299 		impnoops(sc);
300 		goto rawlinkin;
301 
302 	default:
303 		sc->imp_if.if_collisions++;		/* XXX */
304 		goto rawlinkin;
305 	}
306 
307 	/*
308 	 * Data for a protocol.  Dispatch to the appropriate
309 	 * protocol routine (running at software interrupt).
310 	 * If this isn't a raw interface, advance pointer
311 	 * into mbuf past leader.
312 	 */
313 	switch (ip->il_link) {
314 
315 #ifdef INET
316 	case IMPLINK_IP:
317 		m->m_len -= sizeof(struct imp_leader);
318 		m->m_off += sizeof(struct imp_leader);
319 		schednetisr(NETISR_IP);
320 		inq = &ipintrq;
321 		break;
322 #endif
323 
324 	default:
325 	rawlinkin:
326 		impproto.sp_protocol = ip->il_link;
327 		sin = (struct sockaddr_in *)&sc->imp_if.if_addr;
328 		impdst.sin_addr = sin->sin_addr;;
329 		impsrc.sin_addr.s_net = ip->il_network;
330 		impsrc.sin_addr.s_host = ip->il_host;
331 		impsrc.sin_addr.s_imp = ip->il_imp;
332 		raw_input(m, &impproto, (struct sockaddr *)&impdst,
333 		  (struct sockaddr *)&impsrc);
334 		return;
335 	}
336 	if (IF_QFULL(inq)) {
337 		IF_DROP(inq);
338 		goto drop;
339 	}
340 	IF_ENQUEUE(inq, m);
341 	return;
342 
343 drop:
344 	m_freem(m);
345 }
346 
347 /*
348  * Bring the IMP down after notification.
349  */
350 impdown(sc)
351 	struct imp_softc *sc;
352 {
353 
354 	sc->imp_state = IMPS_DOWN;
355 	sc->imp_if.if_flags &= ~IFF_UP;
356 	impmsg(sc, "marked down");
357 	/* notify protocols with messages waiting? */
358 }
359 
360 /*VARARGS*/
361 impmsg(sc, fmt, a1, a2)
362 	struct imp_softc *sc;
363 	char *fmt;
364 	u_int a1;
365 {
366 
367 	printf("imp%d: ", sc->imp_if.if_unit);
368 	printf(fmt, a1, a2);
369 	printf("\n");
370 }
371 
372 /*
373  * ARPAnet 1822 output routine.
374  * Called from higher level protocol routines to set up messages for
375  * transmission to the imp.  Sets up the header and calls impsnd to
376  * enqueue the message for this IMP's hardware driver.
377  */
378 impoutput(ifp, m0, dst)
379 	register struct ifnet *ifp;
380 	struct mbuf *m0;
381 	struct sockaddr *dst;
382 {
383 	register struct imp_leader *imp;
384 	register struct mbuf *m = m0;
385 	int x, dhost, dimp, dlink, len, dnet;
386 
387 COUNT(IMPOUTPUT);
388 	/*
389 	 * Don't even try if the IMP is unavailable.
390 	 */
391 	if (imp_softc[ifp->if_unit].imp_state != IMPS_UP)
392 		goto drop;
393 
394 	switch (dst->sa_family) {
395 
396 #ifdef INET
397 	case AF_INET: {
398 		struct ip *ip = mtod(m0, struct ip *);
399 		struct sockaddr_in *sin = (struct sockaddr_in *)dst;
400 
401 		dhost = sin->sin_addr.s_host;
402 		dimp = sin->sin_addr.s_impno;
403 		dlink = IMPLINK_IP;
404 		dnet = 0;
405 		len = ntohs((u_short)ip->ip_len);
406 		break;
407 	}
408 #endif
409 	case AF_IMPLINK:
410 		goto leaderexists;
411 
412 	default:
413 		printf("imp%d: can't handle af%d\n", ifp->if_unit,
414 			dst->sa_family);
415 		goto drop;
416 	}
417 
418 	/*
419 	 * Add IMP leader.  If there's not enough space in the
420 	 * first mbuf, allocate another.  If that should fail, we
421 	 * drop this sucker.
422 	 */
423 	if (m->m_off > MMAXOFF ||
424 	    MMINOFF + sizeof(struct imp_leader) > m->m_off) {
425 		m = m_get(M_DONTWAIT);
426 		if (m == 0)
427 			goto drop;
428 		m->m_next = m0;
429 		m->m_off = MMINOFF;
430 		m->m_len = sizeof(struct imp_leader);
431 	} else {
432 		m->m_off -= sizeof(struct imp_leader);
433 		m->m_len += sizeof(struct imp_leader);
434 	}
435 	imp = mtod(m, struct imp_leader *);
436 	imp->il_format = IMP_NFF;
437 	imp->il_mtype = IMPTYPE_DATA;
438 	imp->il_network = dnet;
439 	imp->il_host = dhost;
440 	imp->il_imp = htons((u_short)dimp);
441 	imp->il_length =
442 		htons((u_short)(len + sizeof(struct imp_leader)) << 3);
443 	imp->il_link = dlink;
444 	imp->il_flags = imp->il_htype = imp->il_subtype = 0;
445 
446 leaderexists:
447 	/*
448 	 * Hand message to impsnd to perform RFNM counting
449 	 * and eventual transmission.
450 	 */
451 	return (impsnd(ifp, m));
452 drop:
453 	m_freem(m0);
454 	return (0);
455 }
456 
457 /*
458  * Put a message on an interface's output queue.
459  * Perform RFNM counting: no more than 8 message may be
460  * in flight to any one host.
461  */
462 impsnd(ifp, m)
463 	struct ifnet *ifp;
464 	struct mbuf *m;
465 {
466 	register struct imp_leader *ip;
467 	register struct host *hp;
468 	struct impcb *icp;
469 	int x;
470 
471 COUNT(IMPSND);
472 	ip = mtod(m, struct imp_leader *);
473 
474 	/*
475 	 * Do RFNM counting for data messages
476 	 * (no more than 8 outstanding to any host)
477 	 */
478 	x = splimp();
479 	if (ip->il_mtype == IMPTYPE_DATA) {
480 		struct in_addr addr;
481 
482 #ifdef notdef
483                 addr.s_net = ip->il_network;
484 #else
485 		addr.s_net = 0;
486 #endif
487                 addr.s_host = ip->il_host;
488                 addr.s_imp = ip->il_imp;
489 		if ((hp = hostlookup(addr)) == 0)
490 			hp = hostenter(addr);
491 
492 		/*
493 		 * If IMP would block, queue until RFNM
494 		 */
495 		if (hp) {
496 			if (hp->h_rfnm < 8) {
497 				hp->h_rfnm++;
498 				goto enque;
499 			}
500 			if (hp->h_qcnt < 8) {	/* high water mark */
501 				HOST_ENQUE(hp, m);
502 				goto start;
503 			}
504 		}
505 		m_freem(m);
506 		splx(x);
507 		return (0);
508 	}
509 enque:
510 	if (IF_QFULL(&ifp->if_snd)) {
511 		IF_DROP(&ifp->if_snd);
512 		m_freem(m);
513 		splx(x);
514 		return (0);
515 	}
516 	IF_ENQUEUE(&ifp->if_snd, m);
517 start:
518 	splx(x);
519 	icp = &imp_softc[ifp->if_unit].imp_cb;
520 	if (icp->ic_oactive == 0)
521 		(*icp->ic_start)(ifp->if_unit);
522 	return (1);
523 }
524 
525 /*
526  * Put three 1822 NOOPs at the head of the output queue.
527  * Part of host-IMP initialization procedure.
528  * (Should return success/failure, but noone knows
529  * what to do with this, so why bother?)
530  */
531 impnoops(sc)
532 	register struct imp_softc *sc;
533 {
534 	register i;
535 	register struct mbuf *m;
536 	register struct control_leader *cp;
537 	int x;
538 
539 COUNT(IMPNOOPS);
540 	sc->imp_dropcnt = IMP_DROPCNT;
541 	for (i = 0; i < IMP_DROPCNT + 1; i++ ) {
542 		if ((m = m_getclr(M_DONTWAIT)) == 0)
543 			return;
544 		m->m_off = MMINOFF;
545 		m->m_len = sizeof(struct control_leader);
546 		cp = mtod(m, struct control_leader *);
547 		cp->dl_format = IMP_NFF;
548                 cp->dl_link = i;
549                 cp->dl_mtype = IMPTYPE_NOOP;
550 		x = splimp();
551 		IF_PREPEND(&sc->imp_if.if_snd, m);
552 		splx(x);
553 	}
554 	if (sc->imp_cb.ic_oactive == 0)
555 		(*sc->imp_cb.ic_start)(sc->imp_if.if_unit);
556 }
557 
558 #ifdef IMPLEADERS
559 printleader(routine, ip)
560 	char *routine;
561 	register struct imp_leader *ip;
562 {
563 	printf("%s: ", routine);
564 	printbyte((char *)ip, 12);
565 	printf("<fmt=%x,net=%x,flags=%x,mtype=", ip->il_format, ip->il_network,
566 		ip->il_flags);
567 	if (ip->il_mtype <= IMPTYPE_READY)
568 		printf("%s,", impleaders[ip->il_mtype]);
569 	else
570 		printf("%x,", ip->il_mtype);
571 	printf("htype=%x,host=%x,imp=%x,link=", ip->il_htype, ip->il_host,
572 		ntohs(ip->il_imp));
573 	if (ip->il_link == IMPLINK_IP)
574 		printf("ip,");
575 	else
576 		printf("%x,", ip->il_link);
577 	printf("subtype=%x,len=%x>\n",ip->il_subtype,ntohs(ip->il_length)>>3);
578 }
579 
580 printbyte(cp, n)
581 	register char *cp;
582 	int n;
583 {
584 	register i, j, c;
585 
586 	for (i=0; i<n; i++) {
587 		c = *cp++;
588 		for (j=0; j<2; j++)
589 			putchar("0123456789abcdef"[(c>>((1-j)*4))&0xf]);
590 		putchar(' ');
591 	}
592 	putchar('\n');
593 }
594 #endif
595 #endif
596