summaryrefslogtreecommitdiff
path: root/sys/netccitt/if_x25subr.c
blob: 42b15f0621c974723cf2f590a2f86741b7d4a749 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
/*	$NetBSD: if_x25subr.c,v 1.11 1995/06/15 22:38:20 cgd Exp $	*/

/*
 * Copyright (c) 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)if_x25subr.c	8.1 (Berkeley) 6/10/93
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/ioctl.h>
#include <sys/errno.h>
#include <sys/syslog.h>

#include <net/if.h>
#include <net/if_types.h>
#include <net/netisr.h>
#include <net/route.h>

#include <netccitt/x25.h>
#include <netccitt/x25err.h>
#include <netccitt/pk.h>
#include <netccitt/pk_var.h>

#ifdef INET
#include <netinet/in.h>
#include <netinet/in_var.h>
#endif

#ifdef NS
#include <netns/ns.h>
#include <netns/ns_if.h>
#endif

#ifdef ISO
int tp_incoming();
#include <netiso/argo_debug.h>
#include <netiso/iso.h>
#include <netiso/iso_var.h>
#endif

LIST_HEAD(, llinfo_x25) llinfo_x25;
#ifndef _offsetof
#define _offsetof(t, m) ((int)((caddr_t)&((t *)0)->m))
#endif
struct sockaddr *x25_dgram_sockmask;
struct sockaddr_x25 x25_dgmask = {
 _offsetof(struct sockaddr_x25, x25_udata[1]),			/* _len */
 0,								/* _family */
 0,								/* _net */
 { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1}, /* _addr */
 {0},								/* opts */
 -1,								/* _udlen */
 {-1}								/* _udata */
};
 
struct if_x25stats {
	int	ifx_wrongplen;
	int	ifx_nophdr;
} if_x25stats;
int x25_autoconnect = 0;

#define senderr(x) {error = x; goto bad;}
/*
 * Ancillary routines
 */
static struct llinfo_x25 *
x25_lxalloc(rt)
register struct rtentry *rt;
{
	register struct llinfo_x25 *lx;
	register struct sockaddr *dst = rt_key(rt);
	register struct ifaddr *ifa;

	MALLOC(lx, struct llinfo_x25 *, sizeof (*lx), M_PCB, M_NOWAIT);
	if (lx == 0)
		return lx;
	Bzero(lx, sizeof(*lx));
	lx->lx_rt = rt;
	lx->lx_family = dst->sa_family;
	rt->rt_refcnt++;
	if (rt->rt_llinfo) {
		LIST_INSERT_AFTER(
		    (struct llinfo_x25 *)rt->rt_llinfo, lx, lx_list);
	} else {
		rt->rt_llinfo = (caddr_t)lx;
		LIST_INSERT_HEAD(&llinfo_x25, lx, lx_list);
	}
	for (ifa = rt->rt_ifp->if_addrlist.tqh_first; ifa != 0;
	    ifa = ifa->ifa_list.tqe_next) {
		if (ifa->ifa_addr->sa_family == AF_CCITT)
			lx->lx_ia = (struct x25_ifaddr *)ifa;
	}
	return lx;
}
x25_lxfree(lx)
register struct llinfo_x25 *lx;
{
	register struct rtentry *rt = lx->lx_rt;
	register struct pklcd *lcp = lx->lx_lcd;

	if (lcp) {
		lcp->lcd_upper = 0;
		pk_disconnect(lcp);
	}
	if ((rt->rt_llinfo == (caddr_t)lx) && (lx->lx_list.le_next->lx_rt == rt))
		rt->rt_llinfo = (caddr_t)lx->lx_list.le_next;
	else
		rt->rt_llinfo = 0;
	RTFREE(rt);
	LIST_REMOVE(lx, lx_list);
	FREE(lx, M_PCB);
}
/*
 * Process a x25 packet as datagram;
 */
x25_ifinput(lcp, m)
struct pklcd *lcp;
register struct mbuf *m;
{
	struct llinfo_x25 *lx = (struct llinfo_x25 *)lcp->lcd_upnext;
	register struct ifnet *ifp;
	struct ifqueue *inq;
	extern struct timeval time;
	int s, len, isr;
 
	if (m == 0 || lcp->lcd_state != DATA_TRANSFER) {
		x25_connect_callback(lcp, 0);
		return;
	}
	pk_flowcontrol(lcp, 0, 1); /* Generate RR */
	ifp = m->m_pkthdr.rcvif;
	ifp->if_lastchange = time;
	switch (m->m_type) {
	default:
		if (m)
			m_freem(m);
		return;

	case MT_DATA:
		/* FALLTHROUGH */;
	}
	switch (lx->lx_family) {
#ifdef INET
	case AF_INET:
		isr = NETISR_IP;
		inq = &ipintrq;
		break;

#endif
#ifdef NS
	case AF_NS:
		isr = NETISR_NS;
		inq = &nsintrq;
		break;

#endif
#ifdef	ISO
	case AF_ISO:
		isr = NETISR_ISO;
		inq = &clnlintrq;
		break;
#endif
	default:
		m_freem(m);
		ifp->if_noproto++;
		return;
	}
	s = splimp();
	schednetisr(isr);
	if (IF_QFULL(inq)) {
		IF_DROP(inq);
		m_freem(m);
	} else {
		IF_ENQUEUE(inq, m);
		ifp->if_ibytes += m->m_pkthdr.len;
	}
	splx(s);
}
x25_connect_callback(lcp, m)
register struct pklcd *lcp;
register struct mbuf *m;
{
	register struct llinfo_x25 *lx = (struct llinfo_x25 *)lcp->lcd_upnext;
	int do_clear = 1;
	if (m == 0)
		goto refused;
	if (m->m_type != MT_CONTROL) {
		printf("x25_connect_callback: should panic\n");
		goto refused;
	}
	switch (pk_decode(mtod(m, struct x25_packet *))) {
	case CALL_ACCEPTED:
		lcp->lcd_upper = x25_ifinput;
		if (lcp->lcd_sb.sb_mb)
			lcp->lcd_send(lcp); /* XXX start queued packets */
		return;
	default:
		do_clear = 0;
	refused:
		lcp->lcd_upper = 0;
		lx->lx_lcd = 0;
		if (do_clear)
			pk_disconnect(lcp);
		return;
	}
}
#define SA(p) ((struct sockaddr *)(p))
#define RT(p) ((struct rtentry *)(p))

x25_dgram_incoming(lcp, m0)
register struct pklcd *lcp;
struct mbuf *m0;
{
	register struct rtentry *rt, *nrt;
	register struct mbuf *m = m0->m_next; /* m0 has calling sockaddr_x25 */
	void x25_rtrequest();

	rt = rtalloc1(SA(&lcp->lcd_faddr), 0);
	if (rt == 0) {
refuse: 	lcp->lcd_upper = 0;
		pk_close(lcp);
		return;
	}
	rt->rt_refcnt--;
	if ((nrt = RT(rt->rt_llinfo)) == 0 || rt_mask(rt) != x25_dgram_sockmask)
		goto refuse;
	if ((nrt->rt_flags & RTF_UP) == 0) {
		rt->rt_llinfo = (caddr_t)rtalloc1(rt->rt_gateway, 0);
		rtfree(nrt);
		if ((nrt = RT(rt->rt_llinfo)) == 0)
			goto refuse;
		nrt->rt_refcnt--;
	}
	if (nrt->rt_ifa == 0 || nrt->rt_ifa->ifa_rtrequest != x25_rtrequest)
		goto refuse;
	lcp->lcd_send(lcp); /* confirm call */
	x25_rtattach(lcp, nrt);
	m_freem(m);
}

/*
 * X.25 output routine.
 */
x25_ifoutput(ifp, m0, dst, rt)
struct	ifnet *ifp;
struct	mbuf *m0;
struct	sockaddr *dst;
register struct	rtentry *rt;
{
	register struct	mbuf *m = m0;
	register struct	llinfo_x25 *lx;
	struct pklcd *lcp;
	int             s, error = 0;

int plen;
for (plen = 0; m; m = m->m_next)
	plen += m->m_len;
m = m0;

	if ((ifp->if_flags & IFF_UP) == 0)
		senderr(ENETDOWN);
	while (rt == 0 || (rt->rt_flags & RTF_GATEWAY)) {
		if (rt) {
			if (rt->rt_llinfo) {
				rt = (struct rtentry *)rt->rt_llinfo;
				continue;
			}
			dst = rt->rt_gateway;
		}
		if ((rt = rtalloc1(dst, 1)) == 0)
			senderr(EHOSTUNREACH);
		rt->rt_refcnt--;
	}
	/*
	 * Sanity checks.
	 */
	if ((rt->rt_ifp != ifp) ||
	    (rt->rt_flags & (RTF_CLONING | RTF_GATEWAY)) ||
	    ((lx = (struct llinfo_x25 *)rt->rt_llinfo) == 0)) {
		senderr(ENETUNREACH);
	}
if ((m->m_flags & M_PKTHDR) == 0) {
	if_x25stats.ifx_nophdr++;
	m = m_gethdr(M_NOWAIT, MT_HEADER);
	if (m == 0)
		senderr(ENOBUFS);
	m->m_pkthdr.len = plen;
	m->m_next = m0;
}
if (plen != m->m_pkthdr.len) {
	if_x25stats.ifx_wrongplen++;
	m->m_pkthdr.len = plen;
}
next_circuit:
	lcp = lx->lx_lcd;
	if (lcp == 0) {
		lx->lx_lcd = lcp = pk_attach((struct socket *)0);
		if (lcp == 0)
			senderr(ENOBUFS);
		lcp->lcd_upper = x25_connect_callback;
		lcp->lcd_upnext = (caddr_t)lx;
		lcp->lcd_packetsize = lx->lx_ia->ia_xc.xc_psize;
		lcp->lcd_flags = X25_MBS_HOLD;
	}
	switch (lcp->lcd_state) {
	case READY:
		if (dst->sa_family == AF_INET &&
		    ifp->if_type == IFT_X25DDN &&
		    rt->rt_gateway->sa_family != AF_CCITT)
			x25_ddnip_to_ccitt(dst, rt);
		if (rt->rt_gateway->sa_family != AF_CCITT) {
			if ((rt->rt_flags & RTF_XRESOLVE) == 0)
				senderr(EHOSTUNREACH);
		} else if (x25_autoconnect)
			error = pk_connect(lcp,
					(struct sockaddr_x25 *)rt->rt_gateway);
		if (error)
			senderr(error);
		/* FALLTHROUGH */
	case SENT_CALL:
	case DATA_TRANSFER:
		if (sbspace(&lcp->lcd_sb) < 0) {
			lx = lx->lx_list.le_next;
			if (lx->lx_rt != rt)
				senderr(ENOSPC);
			goto next_circuit;
		}
		if (lx->lx_ia)
			lcp->lcd_dg_timer =
				       lx->lx_ia->ia_xc.xc_dg_idletimo;
		pk_send(lcp, m);
		break;
	default:
		/*
		 * We count on the timer routine to close idle
		 * connections, if there are not enough circuits to go
		 * around.
		 *
		 * So throw away data for now.
		 * After we get it all working, we'll rewrite to handle
		 * actively closing connections (other than by timers),
		 * when circuits get tight.
		 *
		 * In the DDN case, the imp itself closes connections
		 * under heavy load.
		 */
		error = ENOBUFS;
	bad:
		if (m)
			m_freem(m);
	}
	return (error);
}

/*
 * Simpleminded timer routine.
 */
x25_iftimeout(ifp)
struct ifnet *ifp;
{
	register struct pkcb *pkcb = 0;
	register struct pklcd **lcpp, *lcp;
	int s = splimp();

	FOR_ALL_PKCBS(pkcb)
	    if (pkcb->pk_ia->ia_ifp == ifp)
		for (lcpp = pkcb->pk_chan + pkcb->pk_maxlcn;
		     --lcpp > pkcb->pk_chan;)
			if ((lcp = *lcpp) &&
			    lcp->lcd_state == DATA_TRANSFER &&
			    (lcp->lcd_flags & X25_DG_CIRCUIT) &&
			    (lcp->lcd_dg_timer && --lcp->lcd_dg_timer == 0)) {
				lcp->lcd_upper(lcp, 0);
			}
	splx(s);
}
/*
 * This routine gets called when validating additions of new routes
 * or deletions of old ones.
 */
void
x25_rtrequest(cmd, rt, dst)
	register struct rtentry *rt;
	struct sockaddr *dst;
{
	register struct llinfo_x25 *lx = (struct llinfo_x25 *)rt->rt_llinfo;
	register struct sockaddr_x25 *sa =(struct sockaddr_x25 *)rt->rt_gateway;
	register struct pklcd *lcp;

	/* would put this pk_init, except routing table doesn't
	   exist yet. */
	if (x25_dgram_sockmask == 0) {
		struct radix_node *rn_addmask();
		x25_dgram_sockmask =
			SA(rn_addmask((caddr_t)&x25_dgmask, 0, 4)->rn_key);
	}
	if (rt->rt_flags & RTF_GATEWAY) {
		if (rt->rt_llinfo)
			RTFREE((struct rtentry *)rt->rt_llinfo);
		rt->rt_llinfo = (cmd == RTM_ADD) ? 
			(caddr_t)rtalloc1(rt->rt_gateway, 1) : 0;
		return;
	}
	if ((rt->rt_flags & RTF_HOST) == 0)
		return;
	if (cmd == RTM_DELETE) {
		while (rt->rt_llinfo)
			x25_lxfree((struct llinfo *)rt->rt_llinfo);
		x25_rtinvert(RTM_DELETE, rt->rt_gateway, rt);
		return;
	}
	if (lx == 0 && (lx = x25_lxalloc(rt)) == 0)
		return;
	if ((lcp = lx->lx_lcd) && lcp->lcd_state != READY) {
		/*
		 * This can only happen on a RTM_CHANGE operation
		 * though cmd will be RTM_ADD.
		 */
		if (lcp->lcd_ceaddr &&
		    Bcmp(rt->rt_gateway, lcp->lcd_ceaddr,
					 lcp->lcd_ceaddr->x25_len) != 0) {
			x25_rtinvert(RTM_DELETE, lcp->lcd_ceaddr, rt);
			lcp->lcd_upper = 0;
			pk_disconnect(lcp);
		}
		lcp = 0;
	}
	x25_rtinvert(RTM_ADD, rt->rt_gateway, rt);
}

int x25_dont_rtinvert = 0;

x25_rtinvert(cmd, sa, rt)
register struct sockaddr *sa;
register struct rtentry *rt;
{
	struct rtentry *rt2 = 0;
	/*
	 * rt_gateway contains PID indicating which proto
	 * family on the other end, so will be different
	 * from general host route via X.25.
	 */
	if (rt->rt_ifp->if_type == IFT_X25DDN || x25_dont_rtinvert)
		return;
	if (sa->sa_family != AF_CCITT)
		return;
	if (cmd != RTM_DELETE) {
		rtrequest(RTM_ADD, sa, rt_key(rt), x25_dgram_sockmask,
				RTF_PROTO2, &rt2);
		if (rt2) {
			rt2->rt_llinfo = (caddr_t) rt;
			rt->rt_refcnt++;
		}
		return;
	}
	rt2 = rt;
	if ((rt = rtalloc1(sa, 0)) == 0 ||
	    (rt->rt_flags & RTF_PROTO2) == 0 ||
	    rt->rt_llinfo != (caddr_t)rt2) {
		printf("x25_rtchange: inverse route screwup\n");
		return;
	} else
		rt2->rt_refcnt--;
	rtrequest(RTM_DELETE, sa, rt_key(rt2), x25_dgram_sockmask,
				0, (struct rtentry **) 0);
}

static struct sockaddr_x25 blank_x25 = {sizeof blank_x25, AF_CCITT};
/*
 * IP to X25 address routine copyright ACC, used by permission.
 */
union imp_addr {
	struct in_addr  ip;
	struct imp {
		u_char		s_net;
		u_char		s_host;
		u_char		s_lh;
		u_char		s_impno;
	}		    imp;
};

/*
 * The following is totally bogus and here only to preserve
 * the IP to X.25 translation.
 */
x25_ddnip_to_ccitt(src, rt)
struct sockaddr_in *src;
register struct rtentry *rt;
{
	register struct sockaddr_x25 *dst = (struct sockaddr_x25 *)rt->rt_gateway;
	union imp_addr imp_addr;
	int             imp_no, imp_port, temp;
	char *x25addr = dst->x25_addr;


	imp_addr.ip = src->sin_addr;
	*dst = blank_x25;
	if ((imp_addr.imp.s_net & 0x80) == 0x00) {	/* class A */
	    imp_no = imp_addr.imp.s_impno;
	    imp_port = imp_addr.imp.s_host;
	} else if ((imp_addr.imp.s_net & 0xc0) == 0x80) {	/* class B */
	    imp_no = imp_addr.imp.s_impno;
	    imp_port = imp_addr.imp.s_lh;
	} else {		/* class C */
	    imp_no = imp_addr.imp.s_impno / 32;
	    imp_port = imp_addr.imp.s_impno % 32;
	}

	x25addr[0] = 12; /* length */
	/* DNIC is cleared by struct copy above */

	if (imp_port < 64) {	/* Physical:  0000 0 IIIHH00 [SS] *//* s_impno
				 *  -> III, s_host -> HH */
	    x25addr[5] = 0;	/* set flag bit */
	    x25addr[6] = imp_no / 100;
	    x25addr[7] = (imp_no % 100) / 10;
	    x25addr[8] = imp_no % 10;
	    x25addr[9] = imp_port / 10;
	    x25addr[10] = imp_port % 10;
	} else {		/* Logical:   0000 1 RRRRR00 [SS]	 *//* s
				 * _host * 256 + s_impno -> RRRRR */
	    temp = (imp_port << 8) + imp_no;
	    x25addr[5] = 1;
	    x25addr[6] = temp / 10000;
	    x25addr[7] = (temp % 10000) / 1000;
	    x25addr[8] = (temp % 1000) / 100;
	    x25addr[9] = (temp % 100) / 10;
	    x25addr[10] = temp % 10;
	}
}

/*
 * This routine is a sketch and is not to be believed!!!!!
 *
 * This is a utility routine to be called by x25 devices when a
 * call request is honored with the intent of starting datagram forwarding.
 */
x25_dg_rtinit(dst, ia, af)
struct sockaddr_x25 *dst;
register struct x25_ifaddr *ia;
{
	struct sockaddr *sa = 0;
	struct rtentry *rt;
	struct in_addr my_addr;
	static struct sockaddr_in sin = {sizeof(sin), AF_INET};

	if (ia->ia_ifp->if_type == IFT_X25DDN && af == AF_INET) {
	/*
	 * Inverse X25 to IP mapping copyright and courtesy ACC.
	 */
		int             imp_no, imp_port, temp;
		union imp_addr imp_addr;
	    {
		/*
		 * First determine our IP addr for network
		 */
		register struct in_ifaddr *ina;

		for (ina = in_ifaddr.tqh_first; ina != 0;
		    ina = ina->ia_list.tqe_next)
			if (ina->ia_ifp == ia->ia_ifp) {
				my_addr = ina->ia_addr.sin_addr;
				break;
			}
	    }
	    {

		register char *x25addr = dst->x25_addr;

		switch (x25addr[5] & 0x0f) {
		  case 0:	/* Physical:  0000 0 IIIHH00 [SS]	 */
		    imp_no =
			((int) (x25addr[6] & 0x0f) * 100) +
			((int) (x25addr[7] & 0x0f) * 10) +
			((int) (x25addr[8] & 0x0f));


		    imp_port =
			((int) (x25addr[9] & 0x0f) * 10) +
			((int) (x25addr[10] & 0x0f));
		    break;
		  case 1:	/* Logical:   0000 1 RRRRR00 [SS]	 */
		    temp = ((int) (x25addr[6] & 0x0f) * 10000)
			+ ((int) (x25addr[7] & 0x0f) * 1000)
			+ ((int) (x25addr[8] & 0x0f) * 100)
			+ ((int) (x25addr[9] & 0x0f) * 10)
			+ ((int) (x25addr[10] & 0x0f));

		    imp_port = temp >> 8;
		    imp_no = temp & 0xff;
		    break;
		  default:
		    return (0L);
		}
		imp_addr.ip = my_addr;
		if ((imp_addr.imp.s_net & 0x80) == 0x00) {
		/* class A */
		    imp_addr.imp.s_host = imp_port;
		    imp_addr.imp.s_impno = imp_no;
		    imp_addr.imp.s_lh = 0;
		} else if ((imp_addr.imp.s_net & 0xc0) == 0x80) {
		/* class B */
		    imp_addr.imp.s_lh = imp_port;
		    imp_addr.imp.s_impno = imp_no;
		} else {
		/* class C */
		    imp_addr.imp.s_impno = (imp_no << 5) + imp_port;
		}
	    }
		sin.sin_addr = imp_addr.ip;
		sa = (struct sockaddr *)&sin;
	} else {
		/*
		 * This uses the X25 routing table to do inverse
		 * lookup of x25 address to sockaddr.
		 */
		if (rt = rtalloc1(SA(dst), 0)) {
			sa = rt->rt_gateway;
			rt->rt_refcnt--;
		}
	}
	/* 
	 * Call to rtalloc1 will create rtentry for reverse path
	 * to callee by virtue of cloning magic and will allocate
	 * space for local control block.
	 */
	if (sa && (rt = rtalloc1(sa, 1)))
		rt->rt_refcnt--;
}
int x25_startproto = 1;

pk_init()
{
	/*
	 * warning, sizeof (struct sockaddr_x25) > 32,
	 * but contains no data of interest beyond 32
	 */
	if (x25_startproto) {
		pk_protolisten(0xcc, 1, x25_dgram_incoming);
		pk_protolisten(0x81, 1, x25_dgram_incoming);
	}
}

struct x25_dgproto {
	u_char spi;
	u_char spilen;
	int (*f)();
} x25_dgprototab[] = {
#if defined(ISO) && defined(TPCONS)
{ 0x0, 0, tp_incoming},
#endif
{ 0xcc, 1, x25_dgram_incoming},
{ 0xcd, 1, x25_dgram_incoming},
{ 0x81, 1, x25_dgram_incoming},
};

pk_user_protolisten(info)
register u_char *info;
{
	register struct x25_dgproto *dp = x25_dgprototab
		    + ((sizeof x25_dgprototab) / (sizeof *dp));
	register struct pklcd *lcp;
	
	while (dp > x25_dgprototab)
		if ((--dp)->spi == info[0])
			goto gotspi;
	return ESRCH;

gotspi:	if (info[1])
		return pk_protolisten(dp->spi, dp->spilen, dp->f);
	for (lcp = pk_listenhead; lcp; lcp = lcp->lcd_listen)
		if (lcp->lcd_laddr.x25_udlen == dp->spilen &&
		    Bcmp(&dp->spi, lcp->lcd_laddr.x25_udata, dp->spilen) == 0) {
			pk_disconnect(lcp);
			return 0;
		}
	return ESRCH;
}

/*
 * This routine transfers an X.25 circuit to or from a routing entry.
 * If the supplied circuit is * in DATA_TRANSFER state, it is added to the
 * routing entry.  If freshly allocated, it glues back the vc from
 * the rtentry to the socket.
 */
pk_rtattach(so, m0)
register struct socket *so;
struct mbuf *m0;
{
	register struct pklcd *lcp = (struct pklcd *)so->so_pcb;
	register struct mbuf *m = m0;
	struct sockaddr *dst = mtod(m, struct sockaddr *);
	register struct rtentry *rt = rtalloc1(dst, 0);
	register struct llinfo_x25 *lx;
	caddr_t cp;
#define ROUNDUP(a) \
	((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
#define transfer_sockbuf(s, f, l) \
	while (m = (s)->sb_mb)\
		{(s)->sb_mb = m->m_act; m->m_act = 0; sbfree((s), m); f(l, m);}

	if (rt)
		rt->rt_refcnt--;
	cp = (dst->sa_len < m->m_len) ? ROUNDUP(dst->sa_len) + (caddr_t)dst : 0;
	while (rt &&
	       ((cp == 0 && rt_mask(rt) != 0) ||
		(cp != 0 && (rt_mask(rt) == 0 ||
			     Bcmp(cp, rt_mask(rt), rt_mask(rt)->sa_len)) != 0)))
			rt = (struct rtentry *)rt->rt_nodes->rn_dupedkey;
	if (rt == 0 || (rt->rt_flags & RTF_GATEWAY) ||
	    (lx = (struct llinfo_x25 *)rt->rt_llinfo) == 0)
		return ESRCH;
	if (lcp == 0)
		return ENOTCONN;
	switch (lcp->lcd_state) {
	default:
		return ENOTCONN;

	case READY:
		/* Detach VC from rtentry */
		if (lx->lx_lcd == 0)
			return ENOTCONN;
		lcp->lcd_so = 0;
		pk_close(lcp);
		lcp = lx->lx_lcd;
		if (lx->lx_list.le_next->lx_rt == rt)
			x25_lxfree(lx);
		lcp->lcd_so = so;
		lcp->lcd_upper = 0;
		lcp->lcd_upnext = 0;
		transfer_sockbuf(&lcp->lcd_sb, sbappendrecord, &so->so_snd);
		soisconnected(so);
		return 0;

	case DATA_TRANSFER:
		/* Add VC to rtentry */
		lcp->lcd_so = 0;
		lcp->lcd_sb = so->so_snd; /* structure copy */
		bzero((caddr_t)&so->so_snd, sizeof(so->so_snd)); /* XXXXXX */
		so->so_pcb = 0;
		x25_rtattach(lcp, rt);
		transfer_sockbuf(&so->so_rcv, x25_ifinput, lcp);
		soisdisconnected(so);
	}
	return 0;
}
x25_rtattach(lcp0, rt)
register struct pklcd *lcp0;
struct rtentry *rt;
{
	register struct llinfo_x25 *lx = (struct llinfo_x25 *)rt->rt_llinfo;
	register struct pklcd *lcp;
	register struct mbuf *m;
	if (lcp = lx->lx_lcd) { /* adding an additional VC */
		if (lcp->lcd_state == READY) {
			transfer_sockbuf(&lcp->lcd_sb, pk_output, lcp0);
			lcp->lcd_upper = 0;
			pk_close(lcp);
		} else {
			lx = x25_lxalloc(rt);
			if (lx == 0)
				return ENOBUFS;
		}
	}
	lx->lx_lcd = lcp = lcp0;
	lcp->lcd_upper = x25_ifinput;
	lcp->lcd_upnext = (caddr_t)lx;
}