xref: /openbsd-src/usr.bin/netstat/show.c (revision 46035553bfdd96e63c94e32da0210227ec2e3cf1)
1 /*	$OpenBSD: show.c,v 1.56 2020/09/15 20:28:27 pamela Exp $	*/
2 /*	$NetBSD: show.c,v 1.1 1996/11/15 18:01:41 gwr Exp $	*/
3 
4 /*
5  * Copyright (c) 1983, 1988, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/socket.h>
34 #include <sys/sysctl.h>
35 
36 #include <net/if.h>
37 #include <net/if_dl.h>
38 #include <net/if_types.h>
39 #include <net/route.h>
40 #include <netinet/in.h>
41 #include <netinet/if_ether.h>
42 #include <netmpls/mpls.h>
43 #include <arpa/inet.h>
44 
45 #include <err.h>
46 #include <errno.h>
47 #include <netdb.h>
48 #include <stdio.h>
49 #include <stddef.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <unistd.h>
53 #include <limits.h>
54 
55 #include "netstat.h"
56 
57 char	*any_ntoa(const struct sockaddr *);
58 char	*link_print(struct sockaddr *);
59 char	*label_print(struct sockaddr *);
60 
61 #define ROUNDUP(a) \
62 	((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
63 #define ADVANCE(x, n) (x += ROUNDUP((n)->sa_len))
64 
65 /*
66  * Definitions for showing gateway flags.
67  */
68 struct bits {
69 	int	b_mask;
70 	char	b_val;
71 };
72 static const struct bits bits[] = {
73 	{ RTF_UP,	'U' },
74 	{ RTF_GATEWAY,	'G' },
75 	{ RTF_HOST,	'H' },
76 	{ RTF_REJECT,	'R' },
77 	{ RTF_DYNAMIC,	'D' },
78 	{ RTF_MODIFIED,	'M' },
79 	{ RTF_DONE,	'd' }, /* Completed -- for routing messages only */
80 	{ RTF_CLONING,	'C' },
81 	{ RTF_MULTICAST,'m' },
82 	{ RTF_LLINFO,	'L' },
83 	{ RTF_STATIC,	'S' },
84 	{ RTF_BLACKHOLE,'B' },
85 	{ RTF_PROTO3,	'3' },
86 	{ RTF_PROTO2,	'2' },
87 	{ RTF_PROTO1,	'1' },
88 	{ RTF_CLONED,	'c' },
89 	{ RTF_CACHED,	'h' },
90 	{ RTF_MPATH,	'P' },
91 	{ RTF_MPLS,	'T' },
92 	{ RTF_LOCAL,	'l' },
93 	{ RTF_BFD,	'F' },
94 	{ RTF_BROADCAST,'b' },
95 	{ RTF_CONNECTED,'n' },
96 	{ 0 }
97 };
98 
99 int	 WID_DST(int);
100 void	 p_rtentry(struct rt_msghdr *);
101 void	 pr_family(int);
102 void	 p_sockaddr(struct sockaddr *, struct sockaddr *, int, int);
103 void	 p_sockaddr_mpls(struct sockaddr *, struct sockaddr *, int, int);
104 void	 p_flags(int, char *);
105 char	*routename4(in_addr_t);
106 char	*routename6(struct sockaddr_in6 *);
107 
108 size_t
109 get_sysctl(const int *mib, u_int mcnt, char **buf)
110 {
111 	size_t needed;
112 
113 	while (1) {
114 		if (sysctl(mib, mcnt, NULL, &needed, NULL, 0) == -1)
115 			err(1, "sysctl-estimate");
116 		if (needed == 0)
117 			break;
118 		if ((*buf = realloc(*buf, needed)) == NULL)
119 			err(1, NULL);
120 		if (sysctl(mib, mcnt, *buf, &needed, NULL, 0) == -1) {
121 			if (errno == ENOMEM)
122 				continue;
123 			err(1, "sysctl");
124 		}
125 		break;
126 	}
127 
128 	return needed;
129 }
130 
131 /*
132  * Print routing tables.
133  */
134 void
135 p_rttables(int af, u_int tableid)
136 {
137 	struct rt_msghdr *rtm;
138 	char *buf = NULL, *next, *lim = NULL;
139 	size_t needed;
140 	int mib[7], mcnt;
141 
142 	mib[0] = CTL_NET;
143 	mib[1] = PF_ROUTE;
144 	mib[2] = 0;
145 	mib[3] = af;
146 	mib[4] = NET_RT_DUMP;
147 	mib[5] = 0;
148 	mib[6] = tableid;
149 	mcnt = 7;
150 
151 	needed = get_sysctl(mib, mcnt, &buf);
152 	lim = buf + needed;
153 
154 	printf("Routing tables\n");
155 
156 	if (buf) {
157 		for (next = buf; next < lim; next += rtm->rtm_msglen) {
158 			rtm = (struct rt_msghdr *)next;
159 			if (rtm->rtm_version != RTM_VERSION)
160 				continue;
161 			p_rtentry(rtm);
162 		}
163 	}
164 	free(buf);
165 }
166 
167 /*
168  * column widths; each followed by one space
169  * width of destination/gateway column
170  * strlen("fe80::aaaa:bbbb:cccc:dddd@gif0") == 30, strlen("/128") == 4
171  */
172 #define	WID_GW(af)	((af) == AF_INET6 ? 30 : 18)
173 
174 int
175 WID_DST(int af)
176 {
177 
178 	switch (af) {
179 	case AF_MPLS:
180 		return 9;
181 	case AF_INET6:
182 		return 34;
183 	default:
184 		return 18;
185 	}
186 }
187 
188 /*
189  * Print header for routing table columns.
190  */
191 void
192 pr_rthdr(int af, int Aflag)
193 {
194 	if (Aflag)
195 		printf("%-*.*s ", PLEN, PLEN, "Address");
196 	switch (af) {
197 	case PF_KEY:
198 		printf("%-18s %-5s %-18s %-5s %-5s %-22s\n",
199 		    "Source", "Port", "Destination",
200 		    "Port", "Proto", "SA(Address/Proto/Type/Direction)");
201 		break;
202 	case PF_MPLS:
203 		printf("%-9s %-9s %-6s %-18s %-6.6s %5.5s %8.8s %5.5s  %4.4s %s\n",
204 		    "In label", "Out label", "Op", "Gateway",
205 		    "Flags", "Refs", "Use", "Mtu", "Prio", "Interface");
206 		break;
207 	default:
208 		printf("%-*.*s %-*.*s %-6.6s %5.5s %8.8s %5.5s  %4.4s %s",
209 		    WID_DST(af), WID_DST(af), "Destination",
210 		    WID_GW(af), WID_GW(af), "Gateway",
211 		    "Flags", "Refs", "Use", "Mtu", "Prio", "Iface");
212 		if (vflag && !Aflag)
213 			printf(" %s", "Label");
214 		putchar('\n');
215 		break;
216 	}
217 }
218 
219 static void
220 get_rtaddrs(int addrs, struct sockaddr *sa, struct sockaddr **rti_info)
221 {
222 	int	i;
223 
224 	for (i = 0; i < RTAX_MAX; i++) {
225 		if (addrs & (1 << i)) {
226 			rti_info[i] = sa;
227 			sa = (struct sockaddr *)((char *)(sa) +
228 			    ROUNDUP(sa->sa_len));
229 		} else
230 			rti_info[i] = NULL;
231 	}
232 }
233 
234 /*
235  * Print a routing table entry.
236  */
237 void
238 p_rtentry(struct rt_msghdr *rtm)
239 {
240 	static int	 old_af = -1;
241 	struct sockaddr	*sa = (struct sockaddr *)((char *)rtm + rtm->rtm_hdrlen);
242 	struct sockaddr	*mask, *rti_info[RTAX_MAX];
243 	char		 ifbuf[IF_NAMESIZE];
244 
245 	if (sa->sa_family == AF_KEY)
246 		return;
247 
248 	get_rtaddrs(rtm->rtm_addrs, sa, rti_info);
249 
250 	if (Fflag && rti_info[RTAX_GATEWAY]->sa_family != sa->sa_family) {
251 		return;
252 	}
253 	if (old_af != sa->sa_family) {
254 		old_af = sa->sa_family;
255 		pr_family(sa->sa_family);
256 		pr_rthdr(sa->sa_family, 0);
257 	}
258 
259 	mask = rti_info[RTAX_NETMASK];
260 	if ((sa = rti_info[RTAX_DST]) == NULL)
261 		return;
262 
263 	p_sockaddr(sa, mask, rtm->rtm_flags, WID_DST(sa->sa_family));
264 	p_sockaddr_mpls(sa, rti_info[RTAX_SRC], rtm->rtm_mpls,
265 	    WID_DST(sa->sa_family));
266 
267 	p_sockaddr(rti_info[RTAX_GATEWAY], NULL, RTF_HOST,
268 	    WID_GW(sa->sa_family));
269 
270 	p_flags(rtm->rtm_flags, "%-6.6s ");
271 	printf("%5u %8llu ", rtm->rtm_rmx.rmx_refcnt,
272 	    rtm->rtm_rmx.rmx_pksent);
273 	if (rtm->rtm_rmx.rmx_mtu)
274 		printf("%5u ", rtm->rtm_rmx.rmx_mtu);
275 	else
276 		printf("%5s ", "-");
277 	putchar((rtm->rtm_rmx.rmx_locks & RTV_MTU) ? 'L' : ' ');
278 	printf("  %2d %-5.16s", rtm->rtm_priority,
279 	    if_indextoname(rtm->rtm_index, ifbuf));
280 	if (vflag && rti_info[RTAX_LABEL])
281 		printf(" %s", ((struct sockaddr_rtlabel *)
282 		    rti_info[RTAX_LABEL])->sr_label);
283 	putchar('\n');
284 }
285 
286 /*
287  * Print address family header before a section of the routing table.
288  */
289 void
290 pr_family(int af)
291 {
292 	char *afname;
293 
294 	switch (af) {
295 	case AF_INET:
296 		afname = "Internet";
297 		break;
298 	case AF_INET6:
299 		afname = "Internet6";
300 		break;
301 	case PF_KEY:
302 		afname = "Encap";
303 		break;
304 	case AF_MPLS:
305 		afname = "MPLS";
306 		break;
307 	default:
308 		afname = NULL;
309 		break;
310 	}
311 	if (afname)
312 		printf("\n%s:\n", afname);
313 	else
314 		printf("\nProtocol Family %d:\n", af);
315 }
316 
317 void
318 p_addr(struct sockaddr *sa, struct sockaddr *mask, int flags)
319 {
320 	p_sockaddr(sa, mask, flags, WID_DST(sa->sa_family));
321 }
322 
323 void
324 p_gwaddr(struct sockaddr *sa, int af)
325 {
326 	p_sockaddr(sa, 0, RTF_HOST, WID_GW(af));
327 }
328 
329 void
330 p_sockaddr(struct sockaddr *sa, struct sockaddr *mask, int flags, int width)
331 {
332 	char *cp;
333 
334 	switch (sa->sa_family) {
335 	case AF_INET6:
336 	    {
337 		struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)sa;
338 		struct in6_addr *in6 = &sa6->sin6_addr;
339 
340 		/*
341 		 * XXX: This is a special workaround for KAME kernels.
342 		 * sin6_scope_id field of SA should be set in the future.
343 		 */
344 		if (IN6_IS_ADDR_LINKLOCAL(in6) ||
345 		    IN6_IS_ADDR_MC_LINKLOCAL(in6) ||
346 		    IN6_IS_ADDR_MC_INTFACELOCAL(in6)) {
347 			/* XXX: override is ok? */
348 			sa6->sin6_scope_id = (u_int32_t)ntohs(*(u_short *)
349 			    &in6->s6_addr[2]);
350 			*(u_short *)&in6->s6_addr[2] = 0;
351 		}
352 		if (flags & RTF_HOST)
353 			cp = routename((struct sockaddr *)sa6);
354 		else
355 			cp = netname((struct sockaddr *)sa6, mask);
356 		break;
357 	    }
358 	case AF_MPLS:
359 		return;
360 	default:
361 		if ((flags & RTF_HOST) || mask == NULL)
362 			cp = routename(sa);
363 		else
364 			cp = netname(sa, mask);
365 		break;
366 	}
367 	if (width < 0)
368 		printf("%s", cp);
369 	else {
370 		if (nflag)
371 			printf("%-*s ", width, cp);
372 		else
373 			printf("%-*.*s ", width, width, cp);
374 	}
375 }
376 
377 static char line[HOST_NAME_MAX+1];
378 static char domain[HOST_NAME_MAX+1];
379 
380 void
381 p_sockaddr_mpls(struct sockaddr *in, struct sockaddr *out, int flags, int width)
382 {
383 	if (in->sa_family != AF_MPLS)
384 		return;
385 
386 	if (flags & MPLS_OP_POP || flags == MPLS_OP_LOCAL) {
387 		printf("%-*s ", width, label_print(in));
388 		printf("%-*s ", width, label_print(NULL));
389 	} else {
390 		printf("%-*s ", width, label_print(in));
391 		printf("%-*s ", width, label_print(out));
392 	}
393 
394 	printf("%-6s ", mpls_op(flags));
395 }
396 
397 void
398 p_flags(int f, char *format)
399 {
400 	char name[33], *flags;
401 	const struct bits *p = bits;
402 
403 	for (flags = name; p->b_mask && flags < &name[sizeof(name) - 2]; p++)
404 		if (p->b_mask & f)
405 			*flags++ = p->b_val;
406 	*flags = '\0';
407 	printf(format, name);
408 }
409 
410 char *
411 routename(struct sockaddr *sa)
412 {
413 	char *cp = NULL;
414 	static int first = 1;
415 
416 	if (first) {
417 		first = 0;
418 		if (gethostname(domain, sizeof(domain)) == 0 &&
419 		    (cp = strchr(domain, '.')))
420 			(void)strlcpy(domain, cp + 1, sizeof(domain));
421 		else
422 			domain[0] = '\0';
423 		cp = NULL;
424 	}
425 
426 	if (sa->sa_len == 0) {
427 		(void)strlcpy(line, "default", sizeof(line));
428 		return (line);
429 	}
430 
431 	switch (sa->sa_family) {
432 	case AF_INET:
433 		return
434 		    (routename4(((struct sockaddr_in *)sa)->sin_addr.s_addr));
435 
436 	case AF_INET6:
437 	    {
438 		struct sockaddr_in6 sin6;
439 
440 		memset(&sin6, 0, sizeof(sin6));
441 		memcpy(&sin6, sa, sa->sa_len);
442 		sin6.sin6_family = AF_INET6;
443 		if (sa->sa_len == sizeof(struct sockaddr_in6) &&
444 		    (IN6_IS_ADDR_LINKLOCAL(&sin6.sin6_addr) ||
445 		     IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr) ||
446 		     IN6_IS_ADDR_MC_INTFACELOCAL(&sin6.sin6_addr)) &&
447 		    sin6.sin6_scope_id == 0) {
448 			sin6.sin6_scope_id =
449 			    ntohs(*(u_int16_t *)&sin6.sin6_addr.s6_addr[2]);
450 			sin6.sin6_addr.s6_addr[2] = 0;
451 			sin6.sin6_addr.s6_addr[3] = 0;
452 		}
453 		return (routename6(&sin6));
454 	    }
455 
456 	case AF_LINK:
457 		return (link_print(sa));
458 	case AF_MPLS:
459 		return (label_print(sa));
460 	case AF_UNSPEC:
461 		if (sa->sa_len == sizeof(struct sockaddr_rtlabel)) {
462 			static char name[RTLABEL_LEN];
463 			struct sockaddr_rtlabel *sr;
464 
465 			sr = (struct sockaddr_rtlabel *)sa;
466 			(void)strlcpy(name, sr->sr_label, sizeof(name));
467 			return (name);
468 		}
469 		/* FALLTHROUGH */
470 	default:
471 		(void)snprintf(line, sizeof(line), "(%d) %s",
472 		    sa->sa_family, any_ntoa(sa));
473 		break;
474 	}
475 	return (line);
476 }
477 
478 char *
479 routename4(in_addr_t in)
480 {
481 	char		*cp = NULL;
482 	struct in_addr	 ina;
483 	struct hostent	*hp;
484 
485 	if (!cp && !nflag) {
486 		if ((hp = gethostbyaddr((char *)&in,
487 		    sizeof(in), AF_INET)) != NULL) {
488 			if ((cp = strchr(hp->h_name, '.')) &&
489 			    !strcmp(cp + 1, domain))
490 				*cp = '\0';
491 			cp = hp->h_name;
492 		}
493 	}
494 	ina.s_addr = in;
495 	strlcpy(line, cp ? cp : inet_ntoa(ina), sizeof(line));
496 
497 	return (line);
498 }
499 
500 char *
501 routename6(struct sockaddr_in6 *sin6)
502 {
503 	int	 niflags = 0;
504 
505 	if (nflag)
506 		niflags |= NI_NUMERICHOST;
507 	else
508 		niflags |= NI_NOFQDN;
509 
510 	if (getnameinfo((struct sockaddr *)sin6, sizeof(*sin6),
511 	    line, sizeof(line), NULL, 0, niflags) != 0)
512 		strncpy(line, "invalid", sizeof(line));
513 
514 	return (line);
515 }
516 
517 /*
518  * Return the name of the network whose address is given.
519  * The address is assumed to be that of a net or subnet, not a host.
520  */
521 char *
522 netname4(in_addr_t in, in_addr_t mask)
523 {
524 	int mbits;
525 
526 	in = ntohl(in);
527 	mask = ntohl(mask);
528 	mbits = mask ? 33 - ffs(mask) : 0;
529 	if (in == INADDR_ANY && mask == INADDR_ANY)
530 		strlcpy(line, "default", sizeof(line));
531 #define C(x)	((x) & 0xff)
532 	else if (mbits < 9)
533 		snprintf(line, sizeof(line), "%u/%d", C(in >> 24), mbits);
534 	else if (mbits < 17)
535 		snprintf(line, sizeof(line), "%u.%u/%d",
536 		    C(in >> 24) , C(in >> 16), mbits);
537 	else if (mbits < 25)
538 		snprintf(line, sizeof(line), "%u.%u.%u/%d",
539 		    C(in >> 24), C(in >> 16), C(in >> 8), mbits);
540 	else
541 		snprintf(line, sizeof(line), "%u.%u.%u.%u/%d", C(in >> 24),
542 		    C(in >> 16), C(in >> 8), C(in), mbits);
543 #undef C
544 	return (line);
545 }
546 
547 char *
548 netname6(struct sockaddr_in6 *sa6, struct sockaddr_in6 *mask)
549 {
550 	struct sockaddr_in6 sin6;
551 	u_char *p;
552 	int masklen, final = 0, illegal = 0;
553 	int i, lim, flag, error;
554 	char hbuf[NI_MAXHOST];
555 
556 	sin6 = *sa6;
557 
558 	flag = 0;
559 	masklen = 0;
560 	if (mask) {
561 		lim = mask->sin6_len - offsetof(struct sockaddr_in6, sin6_addr);
562 		lim = lim < (int)sizeof(struct in6_addr) ?
563 		    lim : (int)sizeof(struct in6_addr);
564 		for (p = (u_char *)&mask->sin6_addr, i = 0; i < lim; p++) {
565 			if (final && *p) {
566 				illegal++;
567 				sin6.sin6_addr.s6_addr[i++] = 0x00;
568 				continue;
569 			}
570 
571 			switch (*p & 0xff) {
572 			case 0xff:
573 				masklen += 8;
574 				break;
575 			case 0xfe:
576 				masklen += 7;
577 				final++;
578 				break;
579 			case 0xfc:
580 				masklen += 6;
581 				final++;
582 				break;
583 			case 0xf8:
584 				masklen += 5;
585 				final++;
586 				break;
587 			case 0xf0:
588 				masklen += 4;
589 				final++;
590 				break;
591 			case 0xe0:
592 				masklen += 3;
593 				final++;
594 				break;
595 			case 0xc0:
596 				masklen += 2;
597 				final++;
598 				break;
599 			case 0x80:
600 				masklen += 1;
601 				final++;
602 				break;
603 			case 0x00:
604 				final++;
605 				break;
606 			default:
607 				final++;
608 				illegal++;
609 				break;
610 			}
611 
612 			if (!illegal)
613 				sin6.sin6_addr.s6_addr[i++] &= *p;
614 			else
615 				sin6.sin6_addr.s6_addr[i++] = 0x00;
616 		}
617 		while (i < (int)sizeof(struct in6_addr))
618 			sin6.sin6_addr.s6_addr[i++] = 0x00;
619 	} else
620 		masklen = 128;
621 
622 	if (masklen == 0 && IN6_IS_ADDR_UNSPECIFIED(&sin6.sin6_addr))
623 		return ("default");
624 
625 	if (illegal)
626 		warnx("illegal prefixlen");
627 
628 	if (nflag)
629 		flag |= NI_NUMERICHOST;
630 	error = getnameinfo((struct sockaddr *)&sin6, sizeof(sin6),
631 	    hbuf, sizeof(hbuf), NULL, 0, flag);
632 	if (error)
633 		snprintf(hbuf, sizeof(hbuf), "invalid");
634 
635 	snprintf(line, sizeof(line), "%s/%d", hbuf, masklen);
636 	return (line);
637 }
638 
639 /*
640  * Return the name of the network whose address is given.
641  * The address is assumed to be that of a net or subnet, not a host.
642  */
643 char *
644 netname(struct sockaddr *sa, struct sockaddr *mask)
645 {
646 	switch (sa->sa_family) {
647 	case AF_INET:
648 		return netname4(((struct sockaddr_in *)sa)->sin_addr.s_addr,
649 		    mask->sa_len == 0 ? 0 :
650 		    ((struct sockaddr_in *)mask)->sin_addr.s_addr);
651 	case AF_INET6:
652 		return netname6((struct sockaddr_in6 *)sa,
653 		    (struct sockaddr_in6 *)mask);
654 	case AF_LINK:
655 		return (link_print(sa));
656 	case AF_MPLS:
657 		return (label_print(sa));
658 	default:
659 		snprintf(line, sizeof(line), "af %d: %s",
660 		    sa->sa_family, any_ntoa(sa));
661 		break;
662 	}
663 	return (line);
664 }
665 
666 static const char hexlist[] = "0123456789abcdef";
667 
668 char *
669 any_ntoa(const struct sockaddr *sa)
670 {
671 	static char obuf[240];
672 	const char *in = sa->sa_data;
673 	char *out = obuf;
674 	int len = sa->sa_len - offsetof(struct sockaddr, sa_data);
675 
676 	*out++ = 'Q';
677 	do {
678 		*out++ = hexlist[(*in >> 4) & 15];
679 		*out++ = hexlist[(*in++)    & 15];
680 		*out++ = '.';
681 	} while (--len > 0 && (out + 3) < &obuf[sizeof(obuf) - 1]);
682 	out[-1] = '\0';
683 	return (obuf);
684 }
685 
686 char *
687 link_print(struct sockaddr *sa)
688 {
689 	struct sockaddr_dl	*sdl = (struct sockaddr_dl *)sa;
690 	u_char			*lla = (u_char *)sdl->sdl_data + sdl->sdl_nlen;
691 
692 	if (sdl->sdl_nlen == 0 && sdl->sdl_alen == 0 &&
693 	    sdl->sdl_slen == 0) {
694 		(void)snprintf(line, sizeof(line), "link#%d", sdl->sdl_index);
695 		return (line);
696 	}
697 	switch (sdl->sdl_type) {
698 	case IFT_ETHER:
699 	case IFT_CARP:
700 		return (ether_ntoa((struct ether_addr *)lla));
701 	default:
702 		return (link_ntoa(sdl));
703 	}
704 }
705 
706 char *
707 mpls_op(u_int32_t type)
708 {
709 	switch (type & (MPLS_OP_PUSH | MPLS_OP_POP | MPLS_OP_SWAP)) {
710 	case MPLS_OP_LOCAL:
711 		return ("LOCAL");
712 	case MPLS_OP_POP:
713 		return ("POP");
714 	case MPLS_OP_SWAP:
715 		return ("SWAP");
716 	case MPLS_OP_PUSH:
717 		return ("PUSH");
718 	default:
719 		return ("?");
720 	}
721 }
722 
723 char *
724 label_print(struct sockaddr *sa)
725 {
726 	struct sockaddr_mpls	*smpls = (struct sockaddr_mpls *)sa;
727 
728 	if (smpls)
729 		(void)snprintf(line, sizeof(line), "%u",
730 		    ntohl(smpls->smpls_label) >> MPLS_LABEL_OFFSET);
731 	else
732 		(void)snprintf(line, sizeof(line), "-");
733 
734 	return (line);
735 }
736