1 /*	if_imp.c	4.20	82/03/28	*/
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 
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 	register struct imp_softc *sc = &imp_softc[unit];
109 
110 	if ((*sc->imp_cb.ic_init)(unit) == 0) {
111 		sc->imp_state = IMPS_DOWN;
112 		sc->imp_if.if_flags &= ~IFF_UP;
113 		return;
114 	}
115 	sc->imp_state = IMPS_INIT;
116 	sc->imp_dropcnt = IMP_DROPCNT;
117 	impnoops(sc);
118 }
119 
120 struct sockproto impproto = { PF_IMPLINK };
121 struct sockaddr_in impdst = { AF_IMPLINK };
122 struct sockaddr_in impsrc = { AF_IMPLINK };
123 
124 /*
125  * ARPAnet 1822 input routine.
126  * Called from hardware input interrupt routine to handle 1822
127  * IMP-host messages.  Type 0 messages (non-control) are
128  * passed to higher level protocol processors on the basis
129  * of link number.  Other type messages (control) are handled here.
130  */
131 impinput(unit, m)
132 	int unit;
133 	register struct mbuf *m;
134 {
135 	register struct imp_leader *ip;
136 	register struct imp_softc *sc = &imp_softc[unit];
137 	register struct host *hp;
138 	register struct ifqueue *inq;
139 	struct control_leader *cp;
140 	struct in_addr addr;
141 	struct mbuf *next;
142 	struct sockaddr_in *sin;
143 
144 COUNT(IMPINPUT);
145 	/* verify leader length. */
146 	if (m->m_len < sizeof(struct control_leader) &&
147 	    (m = m_pullup(m, sizeof(struct control_leader))) == 0)
148 		return;
149 	cp = mtod(m, struct control_leader *);
150 	if (cp->dl_mtype == IMPTYPE_DATA)
151 		if (m->m_len < sizeof(struct imp_leader) &&
152 		    (m = m_pullup(m, sizeof(struct imp_leader))) == 0)
153 			return;
154 	ip = mtod(m, struct imp_leader *);
155 
156 	/* check leader type */
157 	if (ip->il_format != IMP_NFF) {
158 		sc->imp_if.if_collisions++;	/* XXX */
159 		goto drop;
160 	}
161 
162 	/*
163 	 * Certain messages require a host structure.
164 	 * Do this in one shot here.
165 	 */
166 	switch (ip->il_mtype) {
167 
168 	case IMPTYPE_RFNM:
169 	case IMPTYPE_INCOMPLETE:
170 	case IMPTYPE_HOSTDEAD:
171 	case IMPTYPE_HOSTUNREACH:
172 	case IMPTYPE_BADDATA:
173 #ifdef notdef
174 		addr.s_net = ip->il_network;
175 #else
176 		addr.s_net = 0;
177 #endif
178 		addr.s_imp = ip->il_imp;
179 		addr.s_host = ip->il_host;
180 		hp = hostlookup(addr);
181 		break;
182 	}
183 
184 	switch (ip->il_mtype) {
185 
186 	case IMPTYPE_DATA:
187 		break;
188 
189 	/*
190 	 * IMP leader error.  Reset the IMP and discard the packet.
191 	 */
192 	case IMPTYPE_BADLEADER:
193 		/*
194 		 * According to 1822 document, this message
195 		 * will be generated in response to the
196 		 * first noop sent to the IMP after
197 		 * the host resets the IMP interface.
198 		 */
199 		if (sc->imp_state != IMPS_INIT) {
200 			impmsg(sc, "leader error");
201 			hostreset(sc->imp_if.if_net);	/* XXX */
202 			impnoops(sc);
203 		}
204 		goto rawlinkin;
205 
206 	/*
207 	 * IMP going down.  Print message, and if not immediate,
208 	 * set off a timer to insure things will be reset at the
209 	 * appropriate time.
210 	 */
211 	case IMPTYPE_DOWN:
212 		if ((ip->il_link & IMP_DMASK) == 0) {
213 			sc->imp_state = IMPS_GOINGDOWN;
214 			timeout(impdown, (caddr_t)sc, 30 * hz);
215 		}
216 		impmsg(sc, "going down %s",
217 			(u_int)impmessage[ip->il_link&IMP_DMASK]);
218 		goto rawlinkin;
219 
220 	/*
221 	 * A NOP usually seen during the initialization sequence.
222 	 * Compare the local address with that in the message.
223 	 * Reset the local address notion if it doesn't match.
224 	 */
225 	case IMPTYPE_NOOP:
226 		if (sc->imp_state == IMPS_DOWN) {
227 			sc->imp_state = IMPS_INIT;
228 			sc->imp_dropcnt = IMP_DROPCNT;
229 		}
230 		if (sc->imp_state != IMPS_INIT || --sc->imp_dropcnt > 0)
231 			goto drop;
232 		sc->imp_state = IMPS_UP;
233 		sc->imp_if.if_flags |= IFF_UP;
234 		sin = (struct sockaddr_in *)&sc->imp_if.if_addr;
235 		sc->imp_if.if_host[0] = 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 		/* restart output in case something was q'd */
240 		(*sc->imp_cb.ic_start)(sc->imp_if.if_unit);
241 		goto drop;
242 
243 	/*
244 	 * RFNM or INCOMPLETE message, record in
245 	 * host table and prime output routine.
246 	 *
247 	 * SHOULD NOTIFY PROTOCOL ABOUT INCOMPLETES.
248 	 */
249 	case IMPTYPE_RFNM:
250 	case IMPTYPE_INCOMPLETE:
251 		if (hp && hp->h_rfnm)
252 			if (next = hostdeque(hp))
253 				(void) impsnd(&sc->imp_if, next);
254 		goto drop;
255 
256 	/*
257 	 * Host or IMP can't be reached.  Flush any packets
258 	 * awaiting transmission and release the host structure.
259 	 *
260 	 * TODO: NOTIFY THE PROTOCOL
261 	 */
262 	case IMPTYPE_HOSTDEAD:
263 		impmsg(sc, "host dead");	/* XXX */
264 		goto common;			/* XXX */
265 
266 	/* SHOULD SIGNAL ROUTING DAEMON */
267 	case IMPTYPE_HOSTUNREACH:
268 		impmsg(sc, "host unreachable");	/* XXX */
269 	common:
270 		if (hp)
271 			hostfree(hp);		/* won't work right */
272 		goto rawlinkin;
273 
274 	/*
275 	 * Error in data.  Clear RFNM status for this host and send
276 	 * noops to the IMP to clear the interface.
277 	 */
278 	case IMPTYPE_BADDATA:
279 		impmsg(sc, "data error");
280 		if (hp)
281 			hp->h_rfnm = 0;
282 		impnoops(sc);
283 		goto rawlinkin;
284 
285 	/*
286 	 * Interface reset.
287 	 */
288 	case IMPTYPE_RESET:
289 		impmsg(sc, "interface reset");
290 		impnoops(sc);
291 		goto rawlinkin;
292 
293 	default:
294 		sc->imp_if.if_collisions++;		/* XXX */
295 		goto rawlinkin;
296 	}
297 
298 	/*
299 	 * Data for a protocol.  Dispatch to the appropriate
300 	 * protocol routine (running at software interrupt).
301 	 * If this isn't a raw interface, advance pointer
302 	 * into mbuf past leader.
303 	 */
304 	switch (ip->il_link) {
305 
306 #ifdef INET
307 	case IMPLINK_IP:
308 		m->m_len -= sizeof(struct imp_leader);
309 		m->m_off += sizeof(struct imp_leader);
310 		schednetisr(NETISR_IP);
311 		inq = &ipintrq;
312 		break;
313 #endif
314 
315 	default:
316 	rawlinkin:
317 		impproto.sp_protocol = ip->il_link;
318 		sin = (struct sockaddr_in *)&sc->imp_if.if_addr;
319 		impdst.sin_addr = sin->sin_addr;;
320 		impsrc.sin_addr.s_net = ip->il_network;
321 		impsrc.sin_addr.s_host = ip->il_host;
322 		impsrc.sin_addr.s_imp = ip->il_imp;
323 		raw_input(m, &impproto, (struct sockaddr *)&impdst,
324 		  (struct sockaddr *)&impsrc);
325 		return;
326 	}
327 	if (IF_QFULL(inq)) {
328 		IF_DROP(inq);
329 		goto drop;
330 	}
331 	IF_ENQUEUE(inq, m);
332 	return;
333 
334 drop:
335 	m_freem(m);
336 }
337 
338 /*
339  * Bring the IMP down after notification.
340  */
341 impdown(sc)
342 	struct imp_softc *sc;
343 {
344 
345 	sc->imp_state = IMPS_DOWN;
346 	sc->imp_if.if_flags &= ~IFF_UP;
347 	impmsg(sc, "marked down");
348 	/* notify protocols with messages waiting? */
349 }
350 
351 /*VARARGS*/
352 impmsg(sc, fmt, a1, a2)
353 	struct imp_softc *sc;
354 	char *fmt;
355 	u_int a1;
356 {
357 
358 	printf("imp%d: ", sc->imp_if.if_unit);
359 	printf(fmt, a1, a2);
360 	printf("\n");
361 }
362 
363 /*
364  * ARPAnet 1822 output routine.
365  * Called from higher level protocol routines to set up messages for
366  * transmission to the imp.  Sets up the header and calls impsnd to
367  * enqueue the message for this IMP's hardware driver.
368  */
369 impoutput(ifp, m0, dst)
370 	register struct ifnet *ifp;
371 	struct mbuf *m0;
372 	struct sockaddr *dst;
373 {
374 	register struct imp_leader *imp;
375 	register struct mbuf *m = m0;
376 	int x, dhost, dimp, dlink, len, dnet;
377 
378 COUNT(IMPOUTPUT);
379 	/*
380 	 * Don't even try if the IMP is unavailable.
381 	 */
382 	x = imp_softc[ifp->if_unit].imp_state;
383 	if (x == IMPS_DOWN || x == IMPS_GOINGDOWN)
384 		goto drop;
385 
386 	switch (dst->sa_family) {
387 
388 #ifdef INET
389 	case AF_INET: {
390 		struct ip *ip = mtod(m0, struct ip *);
391 		struct sockaddr_in *sin = (struct sockaddr_in *)dst;
392 
393 		dhost = sin->sin_addr.s_host;
394 		dimp = sin->sin_addr.s_impno;
395 		dlink = IMPLINK_IP;
396 		dnet = 0;
397 		len = ntohs((u_short)ip->ip_len);
398 		break;
399 	}
400 #endif
401 	case AF_IMPLINK:
402 		goto leaderexists;
403 
404 	default:
405 		printf("imp%d: can't handle af%d\n", ifp->if_unit,
406 			dst->sa_family);
407 		goto drop;
408 	}
409 
410 	/*
411 	 * Add IMP leader.  If there's not enough space in the
412 	 * first mbuf, allocate another.  If that should fail, we
413 	 * drop this sucker.
414 	 */
415 	if (m->m_off > MMAXOFF ||
416 	    MMINOFF + sizeof(struct imp_leader) > m->m_off) {
417 		m = m_get(M_DONTWAIT);
418 		if (m == 0)
419 			goto drop;
420 		m->m_next = m0;
421 		m->m_off = MMINOFF;
422 		m->m_len = sizeof(struct imp_leader);
423 	} else {
424 		m->m_off -= sizeof(struct imp_leader);
425 		m->m_len += sizeof(struct imp_leader);
426 	}
427 	imp = mtod(m, struct imp_leader *);
428 	imp->il_format = IMP_NFF;
429 	imp->il_mtype = IMPTYPE_DATA;
430 	imp->il_network = dnet;
431 	imp->il_host = dhost;
432 	imp->il_imp = htons((u_short)dimp);
433 	imp->il_length =
434 		htons((u_short)(len + sizeof(struct imp_leader)) << 3);
435 	imp->il_link = dlink;
436 	imp->il_flags = imp->il_htype = imp->il_subtype = 0;
437 
438 leaderexists:
439 	/*
440 	 * Hand message to impsnd to perform RFNM counting
441 	 * and eventual transmission.
442 	 */
443 	return (impsnd(ifp, m));
444 drop:
445 	m_freem(m0);
446 	return (0);
447 }
448 
449 /*
450  * Put a message on an interface's output queue.
451  * Perform RFNM counting: no more than 8 message may be
452  * in flight to any one host.
453  */
454 impsnd(ifp, m)
455 	struct ifnet *ifp;
456 	struct mbuf *m;
457 {
458 	register struct imp_leader *ip;
459 	register struct host *hp;
460 	struct impcb *icp;
461 	int x;
462 
463 COUNT(IMPSND);
464 	ip = mtod(m, struct imp_leader *);
465 
466 	/*
467 	 * Do RFNM counting for data messages
468 	 * (no more than 8 outstanding to any host)
469 	 */
470 	x = splimp();
471 	if (ip->il_mtype == IMPTYPE_DATA) {
472 		struct in_addr addr;
473 
474 #ifdef notdef
475                 addr.s_net = ip->il_network;
476 #else
477 		addr.s_net = 0;
478 #endif
479                 addr.s_host = ip->il_host;
480                 addr.s_imp = ip->il_imp;
481 		if ((hp = hostlookup(addr)) == 0)
482 			hp = hostenter(addr);
483 
484 		/*
485 		 * If IMP would block, queue until RFNM
486 		 */
487 		if (hp) {
488 			if (hp->h_rfnm < 8) {
489 				hp->h_rfnm++;
490 				goto enque;
491 			}
492 			if (hp->h_qcnt < 8) {	/* high water mark */
493 				HOST_ENQUE(hp, m);
494 				goto start;
495 			}
496 		}
497 		m_freem(m);
498 		splx(x);
499 		return (0);
500 	}
501 enque:
502 	if (IF_QFULL(&ifp->if_snd)) {
503 		IF_DROP(&ifp->if_snd);
504 		m_freem(m);
505 		splx(x);
506 		return (0);
507 	}
508 	IF_ENQUEUE(&ifp->if_snd, m);
509 start:
510 	splx(x);
511 	icp = &imp_softc[ifp->if_unit].imp_cb;
512 	if (icp->ic_oactive == 0)
513 		(*icp->ic_start)(ifp->if_unit);
514 	return (1);
515 }
516 
517 /*
518  * Put three 1822 NOOPs at the head of the output queue.
519  * Part of host-IMP initialization procedure.
520  * (Should return success/failure, but noone knows
521  * what to do with this, so why bother?)
522  */
523 impnoops(sc)
524 	register struct imp_softc *sc;
525 {
526 	register i;
527 	register struct mbuf *m;
528 	register struct control_leader *cp;
529 	int x;
530 
531 COUNT(IMPNOOPS);
532 	sc->imp_state = IMPS_INIT;
533 	sc->imp_dropcnt = IMP_DROPCNT;
534 	for (i = 0; i < IMP_DROPCNT + 1; i++ ) {
535 		if ((m = m_getclr(M_DONTWAIT)) == 0)
536 			return;
537 		m->m_off = MMINOFF;
538 		m->m_len = sizeof(struct control_leader);
539 		cp = mtod(m, struct control_leader *);
540 		cp->dl_format = IMP_NFF;
541                 cp->dl_link = i;
542                 cp->dl_mtype = IMPTYPE_NOOP;
543 		x = splimp();
544 		IF_PREPEND(&sc->imp_if.if_snd, m);
545 		splx(x);
546 	}
547 	if (sc->imp_cb.ic_oactive == 0)
548 		(*sc->imp_cb.ic_start)(sc->imp_if.if_unit);
549 }
550 
551 #ifdef IMPLEADERS
552 printleader(routine, ip)
553 	char *routine;
554 	register struct imp_leader *ip;
555 {
556 	printf("%s: ", routine);
557 	printbyte((char *)ip, 12);
558 	printf("<fmt=%x,net=%x,flags=%x,mtype=", ip->il_format, ip->il_network,
559 		ip->il_flags);
560 	if (ip->il_mtype <= IMPTYPE_READY)
561 		printf("%s,", impleaders[ip->il_mtype]);
562 	else
563 		printf("%x,", ip->il_mtype);
564 	printf("htype=%x,host=%x,imp=%x,link=", ip->il_htype, ip->il_host,
565 		ntohs(ip->il_imp));
566 	if (ip->il_link == IMPLINK_IP)
567 		printf("ip,");
568 	else
569 		printf("%x,", ip->il_link);
570 	printf("subtype=%x,len=%x>\n",ip->il_subtype,ntohs(ip->il_length)>>3);
571 }
572 
573 printbyte(cp, n)
574 	register char *cp;
575 	int n;
576 {
577 	register i, j, c;
578 
579 	for (i=0; i<n; i++) {
580 		c = *cp++;
581 		for (j=0; j<2; j++)
582 			putchar("0123456789abcdef"[(c>>((1-j)*4))&0xf]);
583 		putchar(' ');
584 	}
585 	putchar('\n');
586 }
587 #endif
588 #endif
589