1 /*	if_imp.c	4.27	82/04/25	*/
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 #include "../net/if_imp.h"
27 #include "../net/if_imphost.h"
28 #include "../net/ip.h"
29 #include "../net/ip_var.h"
30 #include "../net/route.h"
31 #include <errno.h>
32 
33 /*
34  * IMP software status per interface.
35  * (partially shared with the hardware specific module)
36  *
37  * Each interface is referenced by a network interface structure,
38  * imp_if, which the routing code uses to locate the interface.
39  * This structure contains the output queue for the interface, its
40  * address, ...  IMP specific structures used in connecting the
41  * IMP software modules to the hardware specific interface routines
42  * are stored here.  The common structures are made visible to the
43  * interface driver by passing a pointer to the hardware routine
44  * at "attach" time.
45  *
46  * NOTE: imp_if and imp_cb are assumed adjacent in hardware code.
47  */
48 struct imp_softc {
49 	struct	ifnet imp_if;		/* network visible interface */
50 	struct	impcb imp_cb;		/* hooks to hardware module */
51 	u_char	imp_state;		/* current state of IMP */
52 	char	imp_dropcnt;		/* used during initialization */
53 } imp_softc[NIMP];
54 
55 /*
56  * Messages from IMP regarding why
57  * it's going down.
58  */
59 static char *impmessage[] = {
60 	"in 30 seconds",
61 	"for hardware PM",
62 	"to reload software",
63 	"for emergency reset"
64 };
65 
66 int	impdown(), impinit(), impoutput();
67 
68 /*
69  * IMP attach routine.  Called from hardware device attach routine
70  * at configuration time with a pointer to the UNIBUS device structure.
71  * Sets up local state and returns pointer to base of ifnet+impcb
72  * structures.  This is then used by the device's attach routine
73  * set up its back pointers.
74  */
75 impattach(ui)
76 	struct uba_device *ui;
77 {
78 	struct imp_softc *sc = &imp_softc[ui->ui_unit];
79 	register struct ifnet *ifp = &sc->imp_if;
80 	struct sockaddr_in *sin;
81 
82 COUNT(IMPATTACH);
83 	/* UNIT COULD BE AMBIGUOUS */
84 	ifp->if_unit = ui->ui_unit;
85 	ifp->if_name = "imp";
86 	ifp->if_mtu = IMPMTU - sizeof(struct imp_leader);
87 	ifp->if_net = ui->ui_flags;
88 	/* the host and imp fields will be filled in by the imp */
89 	sin = (struct sockaddr_in *)&ifp->if_addr;
90 	sin->sin_family = AF_INET;
91 	sin->sin_addr = if_makeaddr(ifp->if_net, 0);
92 	ifp->if_init = impinit;
93 	ifp->if_output = impoutput;
94 	/* reset is handled at the hardware level */
95 	if_attach(ifp);
96 	return ((int)&sc->imp_if);
97 }
98 
99 /*
100  * IMP initialization routine: call hardware module to
101  * setup UNIBUS resources, init state and get ready for
102  * NOOPs the IMP should send us, and that we want to drop.
103  */
104 impinit(unit)
105 	int unit;
106 {
107 	int s = splimp();
108 	register struct imp_softc *sc = &imp_softc[unit];
109 
110 COUNT(IMPINIT);
111 	if ((*sc->imp_cb.ic_init)(unit) == 0) {
112 		sc->imp_state = IMPS_DOWN;
113 		sc->imp_if.if_flags &= ~IFF_UP;
114 		splx(s);
115 		return;
116 	}
117 	sc->imp_state = IMPS_INIT;
118 	impnoops(sc);
119 	if_rtinit(&sc->imp_if, RTF_DIRECT|RTF_UP);
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 
127 /*
128  * ARPAnet 1822 input routine.
129  * Called from hardware input interrupt routine to handle 1822
130  * IMP-host messages.  Type 0 messages (non-control) are
131  * passed to higher level protocol processors on the basis
132  * of link number.  Other type messages (control) are handled here.
133  */
134 impinput(unit, m)
135 	int unit;
136 	register struct mbuf *m;
137 {
138 	register struct imp_leader *ip;
139 	register struct imp_softc *sc = &imp_softc[unit];
140 	register struct host *hp;
141 	register struct ifqueue *inq;
142 	struct control_leader *cp;
143 	struct in_addr addr;
144 	struct mbuf *next;
145 	struct sockaddr_in *sin;
146 
147 COUNT(IMPINPUT);
148 	/* verify leader length. */
149 	if (m->m_len < sizeof(struct control_leader) &&
150 	    (m = m_pullup(m, sizeof(struct control_leader))) == 0)
151 		return;
152 	cp = mtod(m, struct control_leader *);
153 	if (cp->dl_mtype == IMPTYPE_DATA)
154 		if (m->m_len < sizeof(struct imp_leader) &&
155 		    (m = m_pullup(m, sizeof(struct imp_leader))) == 0)
156 			return;
157 	ip = mtod(m, struct imp_leader *);
158 
159 	/* check leader type */
160 	if (ip->il_format != IMP_NFF) {
161 		sc->imp_if.if_collisions++;	/* XXX */
162 		goto drop;
163 	}
164 
165 	if (ip->il_mtype != IMPTYPE_DATA) {
166 #ifdef notdef
167 		addr.s_net = ip->il_network;
168 #else
169 		addr.s_net = sc->imp_if.if_net;
170 #endif
171 		addr.s_imp = ip->il_imp;
172 		addr.s_host = ip->il_host;
173 	}
174 	switch (ip->il_mtype) {
175 
176 	case IMPTYPE_DATA:
177 		break;
178 
179 	/*
180 	 * IMP leader error.  Reset the IMP and discard the packet.
181 	 */
182 	case IMPTYPE_BADLEADER:
183 		/*
184 		 * According to 1822 document, this message
185 		 * will be generated in response to the
186 		 * first noop sent to the IMP after
187 		 * the host resets the IMP interface.
188 		 */
189 		if (sc->imp_state != IMPS_INIT) {
190 			impmsg(sc, "leader error");
191 			hostreset(sc->imp_if.if_net);
192 			impnoops(sc);
193 		}
194 		goto drop;
195 
196 	/*
197 	 * IMP going down.  Print message, and if not immediate,
198 	 * set off a timer to insure things will be reset at the
199 	 * appropriate time.
200 	 */
201 	case IMPTYPE_DOWN:
202 		if ((ip->il_link & IMP_DMASK) == 0) {
203 			sc->imp_state = IMPS_GOINGDOWN;
204 			timeout(impdown, (caddr_t)sc, 30 * hz);
205 		}
206 		impmsg(sc, "going down %s",
207 			(u_int)impmessage[ip->il_link&IMP_DMASK]);
208 		goto drop;
209 
210 	/*
211 	 * A NOP usually seen during the initialization sequence.
212 	 * Compare the local address with that in the message.
213 	 * Reset the local address notion if it doesn't match.
214 	 */
215 	case IMPTYPE_NOOP:
216 		if (sc->imp_state == IMPS_DOWN) {
217 			sc->imp_state = IMPS_INIT;
218 			sc->imp_dropcnt = IMP_DROPCNT;
219 		}
220 		if (sc->imp_state == IMPS_INIT && --sc->imp_dropcnt > 0)
221 			goto drop;
222 		sin = (struct sockaddr_in *)&sc->imp_if.if_addr;
223 		if (sin->sin_addr.s_host != ip->il_host ||
224 		    sin->sin_addr.s_imp != ip->il_imp) {
225 			sc->imp_if.if_host[0] =
226 				sin->sin_addr.s_host = ip->il_host;
227 			sin->sin_addr.s_imp = ip->il_imp;
228 			impmsg(sc, "reset (host %d/imp %d)", (u_int)ip->il_host,
229 				ntohs(ip->il_imp));
230 		}
231 		sc->imp_state = IMPS_UP;
232 		sc->imp_if.if_flags |= IFF_UP;
233 		/* restart output in case something was q'd */
234 		(*sc->imp_cb.ic_start)(sc->imp_if.if_unit);
235 		goto drop;
236 
237 	/*
238 	 * RFNM or INCOMPLETE message, send next
239 	 * message on the q.  We could pass incomplete's
240 	 * up to the next level, but this currently isn't
241 	 * needed.
242 	 */
243 	case IMPTYPE_RFNM:
244 	case IMPTYPE_INCOMPLETE:
245 		if (hp = hostlookup(addr)) {
246 			if (hp->h_rfnm == 0)
247 				hp->h_flags &= ~HF_INUSE;
248 			else if (next = hostdeque(hp))
249 				(void) impsnd(&sc->imp_if, next);
250 		}
251 		goto drop;
252 
253 	/*
254 	 * Host or IMP can't be reached.  Flush any packets
255 	 * awaiting transmission and release the host structure.
256 	 */
257 	case IMPTYPE_HOSTDEAD:
258 	case IMPTYPE_HOSTUNREACH: {
259 		int s = splnet();
260 		impnotify(ip->il_mtype, ip, hostlookup(addr));
261 		splx(s);
262 		goto rawlinkin;
263 	}
264 
265 	/*
266 	 * Error in data.  Clear RFNM status for this host and send
267 	 * noops to the IMP to clear the interface.
268 	 */
269 	case IMPTYPE_BADDATA: {
270 		int s;
271 
272 		impmsg(sc, "data error");
273 		s = splnet();
274 		if (hp = hostlookup(addr))
275 			hp->h_rfnm = 0;
276 		splx(s);
277 		impnoops(sc);
278 		goto drop;
279 	}
280 
281 	/*
282 	 * Interface reset.
283 	 */
284 	case IMPTYPE_RESET:
285 		impmsg(sc, "interface reset");
286 		impnoops(sc);
287 		goto drop;
288 
289 	default:
290 		sc->imp_if.if_collisions++;		/* XXX */
291 		goto drop;
292 	}
293 
294 	/*
295 	 * Data for a protocol.  Dispatch to the appropriate
296 	 * protocol routine (running at software interrupt).
297 	 * If this isn't a raw interface, advance pointer
298 	 * into mbuf past leader.
299 	 */
300 	switch (ip->il_link) {
301 
302 #ifdef INET
303 	case IMPLINK_IP:
304 		m->m_len -= sizeof(struct imp_leader);
305 		m->m_off += sizeof(struct imp_leader);
306 		schednetisr(NETISR_IP);
307 		inq = &ipintrq;
308 		break;
309 #endif
310 
311 	default:
312 	rawlinkin:
313 		impproto.sp_protocol = ip->il_link;
314 		sin = (struct sockaddr_in *)&sc->imp_if.if_addr;
315 		impdst.sin_addr = sin->sin_addr;;
316 		impsrc.sin_addr.s_net = ip->il_network;
317 		impsrc.sin_addr.s_host = ip->il_host;
318 		impsrc.sin_addr.s_imp = ip->il_imp;
319 		raw_input(m, &impproto, (struct sockaddr *)&impsrc,
320 		  (struct sockaddr *)&impdst);
321 		return;
322 	}
323 	if (IF_QFULL(inq)) {
324 		IF_DROP(inq);
325 		goto drop;
326 	}
327 	IF_ENQUEUE(inq, m);
328 	return;
329 
330 drop:
331 	m_freem(m);
332 }
333 
334 /*
335  * Bring the IMP down after notification.
336  */
337 impdown(sc)
338 	struct imp_softc *sc;
339 {
340 
341 COUNT(IMPDOWN);
342 	sc->imp_state = IMPS_DOWN;
343 	impmsg(sc, "marked down");
344 	hostreset(sc->imp_if.if_net);
345 	if_down(&sc->imp_if);
346 }
347 
348 /*VARARGS*/
349 impmsg(sc, fmt, a1, a2)
350 	struct imp_softc *sc;
351 	char *fmt;
352 	u_int a1;
353 {
354 
355 COUNT(IMPMSG);
356 	printf("imp%d: ", sc->imp_if.if_unit);
357 	printf(fmt, a1, a2);
358 	printf("\n");
359 }
360 
361 /*
362  * Process an IMP "error" message, passing this
363  * up to the higher level protocol.
364  */
365 impnotify(what, cp, hp)
366 	int what;
367 	struct control_leader *cp;
368 	struct host *hp;
369 {
370 	struct in_addr in;
371 
372 COUNT(IMPNOTIFY);
373 #ifdef notdef
374 	in.s_net = cp->dl_network;
375 #else
376 	in.s_net = 10;			/* XXX */
377 #endif
378 	in.s_host = cp->dl_host;
379 	in.s_imp = cp->dl_imp;
380 	if (cp->dl_link != IMPLINK_IP)
381 		raw_ctlinput(what, (caddr_t)&in);
382 	else
383 		ip_ctlinput(what, (caddr_t)&in);
384 	if (hp) {
385 		hp->h_flags |= (1 << what);
386 		hostfree(hp);
387 	}
388 }
389 
390 /*
391  * ARPAnet 1822 output routine.
392  * Called from higher level protocol routines to set up messages for
393  * transmission to the imp.  Sets up the header and calls impsnd to
394  * enqueue the message for this IMP's hardware driver.
395  */
396 impoutput(ifp, m0, dst)
397 	register struct ifnet *ifp;
398 	struct mbuf *m0;
399 	struct sockaddr *dst;
400 {
401 	register struct imp_leader *imp;
402 	register struct mbuf *m = m0;
403 	int x, dhost, dimp, dlink, len, dnet;
404 	int error = 0;
405 
406 COUNT(IMPOUTPUT);
407 	/*
408 	 * Don't even try if the IMP is unavailable.
409 	 */
410 	if (imp_softc[ifp->if_unit].imp_state != IMPS_UP) {
411 		error = ENETDOWN;
412 		goto drop;
413 	}
414 
415 	switch (dst->sa_family) {
416 
417 #ifdef INET
418 	case AF_INET: {
419 		struct ip *ip = mtod(m0, struct ip *);
420 		struct sockaddr_in *sin = (struct sockaddr_in *)dst;
421 
422 		dhost = sin->sin_addr.s_host;
423 		dimp = sin->sin_addr.s_impno;
424 		dlink = IMPLINK_IP;
425 		dnet = 0;
426 		len = ntohs((u_short)ip->ip_len);
427 		break;
428 	}
429 #endif
430 	case AF_IMPLINK:
431 		goto leaderexists;
432 
433 	default:
434 		printf("imp%d: can't handle af%d\n", ifp->if_unit,
435 			dst->sa_family);
436 		error = EAFNOSUPPORT;
437 		goto drop;
438 	}
439 
440 	/*
441 	 * Add IMP leader.  If there's not enough space in the
442 	 * first mbuf, allocate another.  If that should fail, we
443 	 * drop this sucker.
444 	 */
445 	if (m->m_off > MMAXOFF ||
446 	    MMINOFF + sizeof(struct imp_leader) > m->m_off) {
447 		m = m_get(M_DONTWAIT);
448 		if (m == 0) {
449 			error = ENOBUFS;
450 			goto drop;
451 		}
452 		m->m_next = m0;
453 		m->m_off = MMINOFF;
454 		m->m_len = sizeof(struct imp_leader);
455 	} else {
456 		m->m_off -= sizeof(struct imp_leader);
457 		m->m_len += sizeof(struct imp_leader);
458 	}
459 	imp = mtod(m, struct imp_leader *);
460 	imp->il_format = IMP_NFF;
461 	imp->il_mtype = IMPTYPE_DATA;
462 	imp->il_network = dnet;
463 	imp->il_host = dhost;
464 	imp->il_imp = htons((u_short)dimp);
465 	imp->il_length =
466 		htons((u_short)(len + sizeof(struct imp_leader)) << 3);
467 	imp->il_link = dlink;
468 	imp->il_flags = imp->il_htype = imp->il_subtype = 0;
469 
470 leaderexists:
471 	return (impsnd(ifp, m));
472 drop:
473 	m_freem(m0);
474 	return (error);
475 }
476 
477 /*
478  * Put a message on an interface's output queue.
479  * Perform RFNM counting: no more than 8 message may be
480  * in flight to any one host.
481  */
482 impsnd(ifp, m)
483 	struct ifnet *ifp;
484 	struct mbuf *m;
485 {
486 	register struct imp_leader *ip;
487 	register struct host *hp;
488 	struct impcb *icp;
489 	int s, error;
490 
491 COUNT(IMPSND);
492 	ip = mtod(m, struct imp_leader *);
493 
494 	/*
495 	 * Do RFNM counting for data messages
496 	 * (no more than 8 outstanding to any host)
497 	 */
498 	s = splimp();
499 	if (ip->il_mtype == IMPTYPE_DATA) {
500 		struct in_addr addr;
501 
502 #ifdef notdef
503                 addr.s_net = ip->il_network;
504 #else
505 		addr.s_net = ifp->if_net;	/* XXX */
506 #endif
507                 addr.s_host = ip->il_host;
508                 addr.s_imp = ip->il_imp;
509 		if ((hp = hostlookup(addr)) == 0)
510 			hp = hostenter(addr);
511 		if (hp && (hp->h_flags & (HF_DEAD|HF_UNREACH))) {
512 #ifdef notdef
513 			error = hp->h_flags & HF_DEAD ?
514 				EHOSTDEAD : EHOSTUNREACH;
515 #else
516 			error = ENETUNREACH;
517 			hp->h_timer = HOSTTIMER;
518 			hp->h_flags &= ~HF_INUSE;
519 			goto bad;
520 #endif
521 		}
522 
523 		/*
524 		 * If IMP would block, queue until RFNM
525 		 */
526 		if (hp) {
527 			if (hp->h_rfnm < 8) {
528 				hp->h_rfnm++;
529 				goto enque;
530 			}
531 			if (hp->h_qcnt < 8) {	/* high water mark */
532 				HOST_ENQUE(hp, m);
533 				goto start;
534 			}
535 		}
536 		error = ENOBUFS;
537 		goto bad;
538 	}
539 enque:
540 	if (IF_QFULL(&ifp->if_snd)) {
541 		IF_DROP(&ifp->if_snd);
542 		error = ENOBUFS;
543 bad:
544 		m_freem(m);
545 		splx(s);
546 		return (error);
547 	}
548 	IF_ENQUEUE(&ifp->if_snd, m);
549 start:
550 	splx(s);
551 	icp = &imp_softc[ifp->if_unit].imp_cb;
552 	if (icp->ic_oactive == 0)
553 		(*icp->ic_start)(ifp->if_unit);
554 	return (0);
555 }
556 
557 /*
558  * Put three 1822 NOOPs at the head of the output queue.
559  * Part of host-IMP initialization procedure.
560  * (Should return success/failure, but noone knows
561  * what to do with this, so why bother?)
562  */
563 impnoops(sc)
564 	register struct imp_softc *sc;
565 {
566 	register i;
567 	register struct mbuf *m;
568 	register struct control_leader *cp;
569 	int x;
570 
571 COUNT(IMPNOOPS);
572 	sc->imp_dropcnt = IMP_DROPCNT;
573 	for (i = 0; i < IMP_DROPCNT + 1; i++ ) {
574 		if ((m = m_getclr(M_DONTWAIT)) == 0)
575 			return;
576 		m->m_off = MMINOFF;
577 		m->m_len = sizeof(struct control_leader);
578 		cp = mtod(m, struct control_leader *);
579 		cp->dl_format = IMP_NFF;
580                 cp->dl_link = i;
581                 cp->dl_mtype = IMPTYPE_NOOP;
582 		x = splimp();
583 		IF_PREPEND(&sc->imp_if.if_snd, m);
584 		splx(x);
585 	}
586 	if (sc->imp_cb.ic_oactive == 0)
587 		(*sc->imp_cb.ic_start)(sc->imp_if.if_unit);
588 }
589 #endif
590