xref: /freebsd/contrib/tcpdump/print-atalk.c (revision 5e3190f700637fcfc1a52daeaa4a031fdd2557c7)
1 /*
2  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that: (1) source code distributions
7  * retain the above copyright notice and this paragraph in its entirety, (2)
8  * distributions including binary code include the above copyright notice and
9  * this paragraph in its entirety in the documentation or other materials
10  * provided with the distribution, and (3) all advertising materials mentioning
11  * features or use of this software display the following acknowledgement:
12  * ``This product includes software developed by the University of California,
13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14  * the University nor the names of its contributors may be used to endorse
15  * or promote products derived from this software without specific prior
16  * written permission.
17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20  */
21 
22 /* \summary: AppleTalk printer */
23 
24 #ifdef HAVE_CONFIG_H
25 #include <config.h>
26 #endif
27 
28 #include "netdissect-stdinc.h"
29 
30 #include <stdio.h>
31 #include <string.h>
32 
33 #include "netdissect.h"
34 #include "addrtoname.h"
35 #include "ethertype.h"
36 #include "extract.h"
37 #include "appletalk.h"
38 
39 
40 static const struct tok type2str[] = {
41 	{ ddpRTMP,		"rtmp" },
42 	{ ddpRTMPrequest,	"rtmpReq" },
43 	{ ddpECHO,		"echo" },
44 	{ ddpIP,		"IP" },
45 	{ ddpARP,		"ARP" },
46 	{ ddpKLAP,		"KLAP" },
47 	{ 0,			NULL }
48 };
49 
50 struct aarp {
51 	nd_uint16_t	htype, ptype;
52 	nd_uint8_t	halen, palen;
53 	nd_uint16_t	op;
54 	nd_mac_addr	hsaddr;
55 	uint8_t		psaddr[4];
56 	nd_mac_addr	hdaddr;
57 	uint8_t		pdaddr[4];
58 };
59 
60 static void atp_print(netdissect_options *, const struct atATP *, u_int);
61 static void atp_bitmap_print(netdissect_options *, u_char);
62 static void nbp_print(netdissect_options *, const struct atNBP *, u_int, u_short, u_char, u_char);
63 static const struct atNBPtuple *nbp_tuple_print(netdissect_options *ndo, const struct atNBPtuple *,
64 						const u_char *,
65 						u_short, u_char, u_char);
66 static const struct atNBPtuple *nbp_name_print(netdissect_options *, const struct atNBPtuple *,
67 					       const u_char *);
68 static const char *ataddr_string(netdissect_options *, u_short, u_char);
69 static void ddp_print(netdissect_options *, const u_char *, u_int, u_int, u_short, u_char, u_char);
70 static const char *ddpskt_string(netdissect_options *, u_int);
71 
72 /*
73  * Print LLAP packets received on a physical LocalTalk interface.
74  */
75 void
76 ltalk_if_print(netdissect_options *ndo,
77                const struct pcap_pkthdr *h, const u_char *p)
78 {
79 	u_int hdrlen;
80 
81 	ndo->ndo_protocol = "ltalk";
82 	hdrlen = llap_print(ndo, p, h->len);
83 	if (hdrlen == 0) {
84 		/* Cut short by the snapshot length. */
85 		ndo->ndo_ll_hdr_len += h->caplen;
86 		return;
87 	}
88 	ndo->ndo_ll_hdr_len += hdrlen;
89 }
90 
91 /*
92  * Print AppleTalk LLAP packets.
93  */
94 u_int
95 llap_print(netdissect_options *ndo,
96            const u_char *bp, u_int length)
97 {
98 	const struct LAP *lp;
99 	const struct atDDP *dp;
100 	const struct atShortDDP *sdp;
101 	u_short snet;
102 	u_int hdrlen;
103 
104 	ndo->ndo_protocol = "llap";
105 	if (length < sizeof(*lp)) {
106 		ND_PRINT(" [|llap %u]", length);
107 		return (length);
108 	}
109 	if (!ND_TTEST_LEN(bp, sizeof(*lp))) {
110 		nd_print_trunc(ndo);
111 		return (0);	/* cut short by the snapshot length */
112 	}
113 	lp = (const struct LAP *)bp;
114 	bp += sizeof(*lp);
115 	length -= sizeof(*lp);
116 	hdrlen = sizeof(*lp);
117 	switch (GET_U_1(lp->type)) {
118 
119 	case lapShortDDP:
120 		if (length < ddpSSize) {
121 			ND_PRINT(" [|sddp %u]", length);
122 			return (length);
123 		}
124 		if (!ND_TTEST_LEN(bp, ddpSSize)) {
125 			ND_PRINT(" [|sddp]");
126 			return (0);	/* cut short by the snapshot length */
127 		}
128 		sdp = (const struct atShortDDP *)bp;
129 		ND_PRINT("%s.%s",
130 		    ataddr_string(ndo, 0, GET_U_1(lp->src)),
131 		    ddpskt_string(ndo, GET_U_1(sdp->srcSkt)));
132 		ND_PRINT(" > %s.%s:",
133 		    ataddr_string(ndo, 0, GET_U_1(lp->dst)),
134 		    ddpskt_string(ndo, GET_U_1(sdp->dstSkt)));
135 		bp += ddpSSize;
136 		length -= ddpSSize;
137 		hdrlen += ddpSSize;
138 		ddp_print(ndo, bp, length, GET_U_1(sdp->type), 0,
139 			  GET_U_1(lp->src), GET_U_1(sdp->srcSkt));
140 		break;
141 
142 	case lapDDP:
143 		if (length < ddpSize) {
144 			ND_PRINT(" [|ddp %u]", length);
145 			return (length);
146 		}
147 		if (!ND_TTEST_LEN(bp, ddpSize)) {
148 			ND_PRINT(" [|ddp]");
149 			return (0);	/* cut short by the snapshot length */
150 		}
151 		dp = (const struct atDDP *)bp;
152 		snet = GET_BE_U_2(dp->srcNet);
153 		ND_PRINT("%s.%s",
154 			 ataddr_string(ndo, snet, GET_U_1(dp->srcNode)),
155 			 ddpskt_string(ndo, GET_U_1(dp->srcSkt)));
156 		ND_PRINT(" > %s.%s:",
157 		    ataddr_string(ndo, GET_BE_U_2(dp->dstNet), GET_U_1(dp->dstNode)),
158 		    ddpskt_string(ndo, GET_U_1(dp->dstSkt)));
159 		bp += ddpSize;
160 		length -= ddpSize;
161 		hdrlen += ddpSize;
162 		ddp_print(ndo, bp, length, GET_U_1(dp->type), snet,
163 			  GET_U_1(dp->srcNode), GET_U_1(dp->srcSkt));
164 		break;
165 
166 #ifdef notdef
167 	case lapKLAP:
168 		klap_print(bp, length);
169 		break;
170 #endif
171 
172 	default:
173 		ND_PRINT("%u > %u at-lap#%u %u",
174 		    GET_U_1(lp->src), GET_U_1(lp->dst), GET_U_1(lp->type),
175 		    length);
176 		break;
177 	}
178 	return (hdrlen);
179 }
180 
181 /*
182  * Print EtherTalk/TokenTalk packets (or FDDITalk, or whatever it's called
183  * when it runs over FDDI; yes, I've seen FDDI captures with AppleTalk
184  * packets in them).
185  */
186 void
187 atalk_print(netdissect_options *ndo,
188             const u_char *bp, u_int length)
189 {
190 	const struct atDDP *dp;
191 	u_short snet;
192 
193 	ndo->ndo_protocol = "atalk";
194         if(!ndo->ndo_eflag)
195             ND_PRINT("AT ");
196 
197 	if (length < ddpSize) {
198 		ND_PRINT(" [|ddp %u]", length);
199 		return;
200 	}
201 	if (!ND_TTEST_LEN(bp, ddpSize)) {
202 		ND_PRINT(" [|ddp]");
203 		return;
204 	}
205 	dp = (const struct atDDP *)bp;
206 	snet = GET_BE_U_2(dp->srcNet);
207 	ND_PRINT("%s.%s", ataddr_string(ndo, snet, GET_U_1(dp->srcNode)),
208 		 ddpskt_string(ndo, GET_U_1(dp->srcSkt)));
209 	ND_PRINT(" > %s.%s: ",
210 	       ataddr_string(ndo, GET_BE_U_2(dp->dstNet), GET_U_1(dp->dstNode)),
211 	       ddpskt_string(ndo, GET_U_1(dp->dstSkt)));
212 	bp += ddpSize;
213 	length -= ddpSize;
214 	ddp_print(ndo, bp, length, GET_U_1(dp->type), snet,
215 		  GET_U_1(dp->srcNode), GET_U_1(dp->srcSkt));
216 }
217 
218 /* XXX should probably pass in the snap header and do checks like arp_print() */
219 void
220 aarp_print(netdissect_options *ndo,
221            const u_char *bp, u_int length)
222 {
223 	const struct aarp *ap;
224 
225 #define AT(member) ataddr_string(ndo, (ap->member[1]<<8)|ap->member[2],ap->member[3])
226 
227 	ndo->ndo_protocol = "aarp";
228 	ND_PRINT("aarp ");
229 	ap = (const struct aarp *)bp;
230 	if (!ND_TTEST_SIZE(ap)) {
231 		/* Just bail if we don't have the whole chunk. */
232 		nd_print_trunc(ndo);
233 		return;
234 	}
235 	if (length < sizeof(*ap)) {
236 		ND_PRINT(" [|aarp %u]", length);
237 		return;
238 	}
239 	if (GET_BE_U_2(ap->htype) == 1 &&
240 	    GET_BE_U_2(ap->ptype) == ETHERTYPE_ATALK &&
241 	    GET_U_1(ap->halen) == MAC_ADDR_LEN && GET_U_1(ap->palen) == 4)
242 		switch (GET_BE_U_2(ap->op)) {
243 
244 		case 1:				/* request */
245 			ND_PRINT("who-has %s tell %s", AT(pdaddr), AT(psaddr));
246 			return;
247 
248 		case 2:				/* response */
249 			ND_PRINT("reply %s is-at %s", AT(psaddr), GET_ETHERADDR_STRING(ap->hsaddr));
250 			return;
251 
252 		case 3:				/* probe (oy!) */
253 			ND_PRINT("probe %s tell %s", AT(pdaddr), AT(psaddr));
254 			return;
255 		}
256 	ND_PRINT("len %u op %u htype %u ptype %#x halen %u palen %u",
257 	    length, GET_BE_U_2(ap->op), GET_BE_U_2(ap->htype),
258 	    GET_BE_U_2(ap->ptype), GET_U_1(ap->halen), GET_U_1(ap->palen));
259 }
260 
261 /*
262  * Print AppleTalk Datagram Delivery Protocol packets.
263  */
264 static void
265 ddp_print(netdissect_options *ndo,
266           const u_char *bp, u_int length, u_int t,
267           u_short snet, u_char snode, u_char skt)
268 {
269 
270 	switch (t) {
271 
272 	case ddpNBP:
273 		nbp_print(ndo, (const struct atNBP *)bp, length, snet, snode, skt);
274 		break;
275 
276 	case ddpATP:
277 		atp_print(ndo, (const struct atATP *)bp, length);
278 		break;
279 
280 	case ddpEIGRP:
281 		eigrp_print(ndo, bp, length);
282 		break;
283 
284 	default:
285 		ND_PRINT(" at-%s %u", tok2str(type2str, NULL, t), length);
286 		break;
287 	}
288 }
289 
290 static void
291 atp_print(netdissect_options *ndo,
292           const struct atATP *ap, u_int length)
293 {
294 	uint8_t control;
295 	uint32_t data;
296 
297 	if ((const u_char *)(ap + 1) > ndo->ndo_snapend) {
298 		/* Just bail if we don't have the whole chunk. */
299 		nd_print_trunc(ndo);
300 		return;
301 	}
302 	if (length < sizeof(*ap)) {
303 		ND_PRINT(" [|atp %u]", length);
304 		return;
305 	}
306 	length -= sizeof(*ap);
307 	control = GET_U_1(ap->control);
308 	switch (control & 0xc0) {
309 
310 	case atpReqCode:
311 		ND_PRINT(" atp-req%s %u",
312 			     control & atpXO? " " : "*",
313 			     GET_BE_U_2(ap->transID));
314 
315 		atp_bitmap_print(ndo, GET_U_1(ap->bitmap));
316 
317 		if (length != 0)
318 			ND_PRINT(" [len=%u]", length);
319 
320 		switch (control & (atpEOM|atpSTS)) {
321 		case atpEOM:
322 			ND_PRINT(" [EOM]");
323 			break;
324 		case atpSTS:
325 			ND_PRINT(" [STS]");
326 			break;
327 		case atpEOM|atpSTS:
328 			ND_PRINT(" [EOM,STS]");
329 			break;
330 		}
331 		break;
332 
333 	case atpRspCode:
334 		ND_PRINT(" atp-resp%s%u:%u (%u)",
335 			     control & atpEOM? "*" : " ",
336 			     GET_BE_U_2(ap->transID), GET_U_1(ap->bitmap),
337 			     length);
338 		switch (control & (atpXO|atpSTS)) {
339 		case atpXO:
340 			ND_PRINT(" [XO]");
341 			break;
342 		case atpSTS:
343 			ND_PRINT(" [STS]");
344 			break;
345 		case atpXO|atpSTS:
346 			ND_PRINT(" [XO,STS]");
347 			break;
348 		}
349 		break;
350 
351 	case atpRelCode:
352 		ND_PRINT(" atp-rel  %u", GET_BE_U_2(ap->transID));
353 
354 		atp_bitmap_print(ndo, GET_U_1(ap->bitmap));
355 
356 		/* length should be zero */
357 		if (length)
358 			ND_PRINT(" [len=%u]", length);
359 
360 		/* there shouldn't be any control flags */
361 		if (control & (atpXO|atpEOM|atpSTS)) {
362 			char c = '[';
363 			if (control & atpXO) {
364 				ND_PRINT("%cXO", c);
365 				c = ',';
366 			}
367 			if (control & atpEOM) {
368 				ND_PRINT("%cEOM", c);
369 				c = ',';
370 			}
371 			if (control & atpSTS) {
372 				ND_PRINT("%cSTS", c);
373 			}
374 			ND_PRINT("]");
375 		}
376 		break;
377 
378 	default:
379 		ND_PRINT(" atp-0x%x  %u (%u)", control,
380 			     GET_BE_U_2(ap->transID), length);
381 		break;
382 	}
383 	data = GET_BE_U_4(ap->userData);
384 	if (data != 0)
385 		ND_PRINT(" 0x%x", data);
386 }
387 
388 static void
389 atp_bitmap_print(netdissect_options *ndo,
390                  u_char bm)
391 {
392 	u_int i;
393 
394 	/*
395 	 * The '& 0xff' below is needed for compilers that want to sign
396 	 * extend a u_char, which is the case with the Ultrix compiler.
397 	 * (gcc is smart enough to eliminate it, at least on the Sparc).
398 	 */
399 	if ((bm + 1) & (bm & 0xff)) {
400 		char c = '<';
401 		for (i = 0; bm; ++i) {
402 			if (bm & 1) {
403 				ND_PRINT("%c%u", c, i);
404 				c = ',';
405 			}
406 			bm >>= 1;
407 		}
408 		ND_PRINT(">");
409 	} else {
410 		for (i = 0; bm; ++i)
411 			bm >>= 1;
412 		if (i > 1)
413 			ND_PRINT("<0-%u>", i - 1);
414 		else
415 			ND_PRINT("<0>");
416 	}
417 }
418 
419 static void
420 nbp_print(netdissect_options *ndo,
421           const struct atNBP *np, u_int length, u_short snet,
422           u_char snode, u_char skt)
423 {
424 	const struct atNBPtuple *tp =
425 		(const struct atNBPtuple *)((const u_char *)np + nbpHeaderSize);
426 	uint8_t control;
427 	u_int i;
428 	const u_char *ep;
429 
430 	if (length < nbpHeaderSize) {
431 		ND_PRINT(" truncated-nbp %u", length);
432 		return;
433 	}
434 
435 	length -= nbpHeaderSize;
436 	if (length < 8) {
437 		/* must be room for at least one tuple */
438 		ND_PRINT(" truncated-nbp %u", length + nbpHeaderSize);
439 		return;
440 	}
441 	/* ep points to end of available data */
442 	ep = ndo->ndo_snapend;
443 	if ((const u_char *)tp > ep) {
444 		nd_print_trunc(ndo);
445 		return;
446 	}
447 	control = GET_U_1(np->control);
448 	switch (i = (control & 0xf0)) {
449 
450 	case nbpBrRq:
451 	case nbpLkUp:
452 		ND_PRINT(i == nbpLkUp? " nbp-lkup %u:":" nbp-brRq %u:",
453 			 GET_U_1(np->id));
454 		if ((const u_char *)(tp + 1) > ep) {
455 			nd_print_trunc(ndo);
456 			return;
457 		}
458 		(void)nbp_name_print(ndo, tp, ep);
459 		/*
460 		 * look for anomalies: the spec says there can only
461 		 * be one tuple, the address must match the source
462 		 * address and the enumerator should be zero.
463 		 */
464 		if ((control & 0xf) != 1)
465 			ND_PRINT(" [ntup=%u]", control & 0xf);
466 		if (GET_U_1(tp->enumerator))
467 			ND_PRINT(" [enum=%u]", GET_U_1(tp->enumerator));
468 		if (GET_BE_U_2(tp->net) != snet ||
469 		    GET_U_1(tp->node) != snode ||
470 		    GET_U_1(tp->skt) != skt)
471 			ND_PRINT(" [addr=%s.%u]",
472 			    ataddr_string(ndo, GET_BE_U_2(tp->net),
473 					  GET_U_1(tp->node)),
474 			    GET_U_1(tp->skt));
475 		break;
476 
477 	case nbpLkUpReply:
478 		ND_PRINT(" nbp-reply %u:", GET_U_1(np->id));
479 
480 		/* print each of the tuples in the reply */
481 		for (i = control & 0xf; i != 0 && tp; i--)
482 			tp = nbp_tuple_print(ndo, tp, ep, snet, snode, skt);
483 		break;
484 
485 	default:
486 		ND_PRINT(" nbp-0x%x  %u (%u)", control, GET_U_1(np->id),
487 			 length);
488 		break;
489 	}
490 }
491 
492 /* print a counted string */
493 static const u_char *
494 print_cstring(netdissect_options *ndo,
495               const u_char *cp, const u_char *ep)
496 {
497 	u_int length;
498 
499 	if (cp >= ep) {
500 		nd_print_trunc(ndo);
501 		return (0);
502 	}
503 	length = GET_U_1(cp);
504 	cp++;
505 
506 	/* Spec says string can be at most 32 bytes long */
507 	if (length > 32) {
508 		ND_PRINT("[len=%u]", length);
509 		return (0);
510 	}
511 	while (length != 0) {
512 		if (cp >= ep) {
513 			nd_print_trunc(ndo);
514 			return (0);
515 		}
516 		fn_print_char(ndo, GET_U_1(cp));
517 		cp++;
518 		length--;
519 	}
520 	return (cp);
521 }
522 
523 static const struct atNBPtuple *
524 nbp_tuple_print(netdissect_options *ndo,
525                 const struct atNBPtuple *tp, const u_char *ep,
526                 u_short snet, u_char snode, u_char skt)
527 {
528 	const struct atNBPtuple *tpn;
529 
530 	if ((const u_char *)(tp + 1) > ep) {
531 		nd_print_trunc(ndo);
532 		return 0;
533 	}
534 	tpn = nbp_name_print(ndo, tp, ep);
535 
536 	/* if the enumerator isn't 1, print it */
537 	if (GET_U_1(tp->enumerator) != 1)
538 		ND_PRINT("(%u)", GET_U_1(tp->enumerator));
539 
540 	/* if the socket doesn't match the src socket, print it */
541 	if (GET_U_1(tp->skt) != skt)
542 		ND_PRINT(" %u", GET_U_1(tp->skt));
543 
544 	/* if the address doesn't match the src address, it's an anomaly */
545 	if (GET_BE_U_2(tp->net) != snet ||
546 	    GET_U_1(tp->node) != snode)
547 		ND_PRINT(" [addr=%s]",
548 		    ataddr_string(ndo, GET_BE_U_2(tp->net), GET_U_1(tp->node)));
549 
550 	return (tpn);
551 }
552 
553 static const struct atNBPtuple *
554 nbp_name_print(netdissect_options *ndo,
555                const struct atNBPtuple *tp, const u_char *ep)
556 {
557 	const u_char *cp = (const u_char *)tp + nbpTupleSize;
558 
559 	ND_PRINT(" ");
560 
561 	/* Object */
562 	ND_PRINT("\"");
563 	if ((cp = print_cstring(ndo, cp, ep)) != NULL) {
564 		/* Type */
565 		ND_PRINT(":");
566 		if ((cp = print_cstring(ndo, cp, ep)) != NULL) {
567 			/* Zone */
568 			ND_PRINT("@");
569 			if ((cp = print_cstring(ndo, cp, ep)) != NULL)
570 				ND_PRINT("\"");
571 		}
572 	}
573 	return ((const struct atNBPtuple *)cp);
574 }
575 
576 
577 #define HASHNAMESIZE 4096
578 
579 struct hnamemem {
580 	u_int addr;
581 	char *name;
582 	struct hnamemem *nxt;
583 };
584 
585 static struct hnamemem hnametable[HASHNAMESIZE];
586 
587 static const char *
588 ataddr_string(netdissect_options *ndo,
589               u_short atnet, u_char athost)
590 {
591 	struct hnamemem *tp, *tp2;
592 	u_int i = (atnet << 8) | athost;
593 	char nambuf[256+1];
594 	static int first = 1;
595 	FILE *fp;
596 
597 	/*
598 	 * Are we doing address to name resolution?
599 	 */
600 	if (!ndo->ndo_nflag) {
601 		/*
602 		 * Yes.  Have we tried to open and read an AppleTalk
603 		 * number to name map file?
604 		 */
605 		if (!first) {
606 			/*
607 			 * No; try to do so.
608 			 */
609 			first = 0;
610 			fp = fopen("/etc/atalk.names", "r");
611 			if (fp != NULL) {
612 				char line[256];
613 				u_int i1, i2;
614 
615 				while (fgets(line, sizeof(line), fp)) {
616 					if (line[0] == '\n' || line[0] == 0 ||
617 					    line[0] == '#')
618 						continue;
619 					if (sscanf(line, "%u.%u %256s", &i1,
620 					    &i2, nambuf) == 3)
621 						/* got a hostname. */
622 						i2 |= (i1 << 8);
623 					else if (sscanf(line, "%u %256s", &i1,
624 					    nambuf) == 2)
625 						/* got a net name */
626 						i2 = (i1 << 8) | 255;
627 					else
628 						continue;
629 
630 					for (tp = &hnametable[i2 & (HASHNAMESIZE-1)];
631 					     tp->nxt; tp = tp->nxt)
632 						;
633 					tp->addr = i2;
634 					tp->nxt = newhnamemem(ndo);
635 					tp->name = strdup(nambuf);
636 					if (tp->name == NULL)
637 						(*ndo->ndo_error)(ndo,
638 						    S_ERR_ND_MEM_ALLOC,
639 						    "%s: strdup(nambuf)", __func__);
640 				}
641 				fclose(fp);
642 			}
643 		}
644 	}
645 
646 	/*
647 	 * Now try to look up the address in the table.
648 	 */
649 	for (tp = &hnametable[i & (HASHNAMESIZE-1)]; tp->nxt; tp = tp->nxt)
650 		if (tp->addr == i)
651 			return (tp->name);
652 
653 	/* didn't have the node name -- see if we've got the net name */
654 	i |= 255;
655 	for (tp2 = &hnametable[i & (HASHNAMESIZE-1)]; tp2->nxt; tp2 = tp2->nxt)
656 		if (tp2->addr == i) {
657 			tp->addr = (atnet << 8) | athost;
658 			tp->nxt = newhnamemem(ndo);
659 			(void)snprintf(nambuf, sizeof(nambuf), "%s.%u",
660 			    tp2->name, athost);
661 			tp->name = strdup(nambuf);
662 			if (tp->name == NULL)
663 				(*ndo->ndo_error)(ndo, S_ERR_ND_MEM_ALLOC,
664 					"%s: strdup(nambuf)", __func__);
665 			return (tp->name);
666 		}
667 
668 	tp->addr = (atnet << 8) | athost;
669 	tp->nxt = newhnamemem(ndo);
670 	if (athost != 255)
671 		(void)snprintf(nambuf, sizeof(nambuf), "%u.%u", atnet, athost);
672 	else
673 		(void)snprintf(nambuf, sizeof(nambuf), "%u", atnet);
674 	tp->name = strdup(nambuf);
675 	if (tp->name == NULL)
676 		(*ndo->ndo_error)(ndo, S_ERR_ND_MEM_ALLOC,
677 				  "%s: strdup(nambuf)", __func__);
678 
679 	return (tp->name);
680 }
681 
682 static const struct tok skt2str[] = {
683 	{ rtmpSkt,	"rtmp" },	/* routing table maintenance */
684 	{ nbpSkt,	"nis" },	/* name info socket */
685 	{ echoSkt,	"echo" },	/* AppleTalk echo protocol */
686 	{ zipSkt,	"zip" },	/* zone info protocol */
687 	{ 0,		NULL }
688 };
689 
690 static const char *
691 ddpskt_string(netdissect_options *ndo,
692               u_int skt)
693 {
694 	static char buf[8];
695 
696 	if (ndo->ndo_nflag) {
697 		(void)snprintf(buf, sizeof(buf), "%u", skt);
698 		return (buf);
699 	}
700 	return (tok2str(skt2str, "%u", skt));
701 }
702