xref: /freebsd/usr.bin/netstat/if.c (revision 2da066ef6d85d3f7cd8aaec14369d66254836536)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2013 Gleb Smirnoff <glebius@FreeBSD.org>
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/param.h>
34 #include <sys/protosw.h>
35 #include <sys/socket.h>
36 #include <sys/socketvar.h>
37 #include <sys/time.h>
38 
39 #include <net/if.h>
40 #include <net/if_dl.h>
41 #include <net/if_types.h>
42 #include <net/ethernet.h>
43 #include <netinet/in.h>
44 #include <netinet/in_var.h>
45 #include <arpa/inet.h>
46 #ifdef PF
47 #include <net/pfvar.h>
48 #include <net/pflow.h>
49 #include <net/if_pfsync.h>
50 #endif
51 
52 #include <err.h>
53 #include <errno.h>
54 #include <ifaddrs.h>
55 #include <libutil.h>
56 #ifdef INET6
57 #include <netdb.h>
58 #endif
59 #include <signal.h>
60 #include <stdbool.h>
61 #include <stdint.h>
62 #include <stdio.h>
63 #include <stdlib.h>
64 #include <string.h>
65 #include <sysexits.h>
66 #include <unistd.h>
67 #include <libxo/xo.h>
68 
69 #include "netstat.h"
70 
71 static void sidewaysintpr(void);
72 
73 #ifdef PF
74 static const char* pfsyncacts[] = {
75 	/* PFSYNC_ACT_CLR */		"clear all request",
76 	/* PFSYNC_ACT_INS_1301 */	"13.1 state insert",
77 	/* PFSYNC_ACT_INS_ACK */	"state inserted ack",
78 	/* PFSYNC_ACT_UPD_1301 */	"13.1 state update",
79 	/* PFSYNC_ACT_UPD_C */		"compressed state update",
80 	/* PFSYNC_ACT_UPD_REQ */	"uncompressed state request",
81 	/* PFSYNC_ACT_DEL */		"state delete",
82 	/* PFSYNC_ACT_DEL_C */		"compressed state delete",
83 	/* PFSYNC_ACT_INS_F */		"fragment insert",
84 	/* PFSYNC_ACT_DEL_F */		"fragment delete",
85 	/* PFSYNC_ACT_BUS */		"bulk update mark",
86 	/* PFSYNC_ACT_TDB */		"TDB replay counter update",
87 	/* PFSYNC_ACT_EOF */		"end of frame mark",
88 	/* PFSYNC_ACT_INS_1400 */	"state insert",
89 	/* PFSYNC_ACT_UPD_1400 */	"state update",
90 };
91 
92 static const char* pfsyncacts_name[] = {
93 	/* PFSYNC_ACT_CLR */		"clear-all-request",
94 	/* PFSYNC_ACT_INS_1301 */	"state-insert-1301",
95 	/* PFSYNC_ACT_INS_ACK */	"state-inserted-ack",
96 	/* PFSYNC_ACT_UPD_1301 */	"state-update-1301",
97 	/* PFSYNC_ACT_UPD_C */		"compressed-state-update",
98 	/* PFSYNC_ACT_UPD_REQ */	"uncompressed-state-request",
99 	/* PFSYNC_ACT_DEL */		"state-delete",
100 	/* PFSYNC_ACT_DEL_C */		"compressed-state-delete",
101 	/* PFSYNC_ACT_INS_F */		"fragment-insert",
102 	/* PFSYNC_ACT_DEL_F */		"fragment-delete",
103 	/* PFSYNC_ACT_BUS */		"bulk-update-mark",
104 	/* PFSYNC_ACT_TDB */		"TDB-replay-counter-update",
105 	/* PFSYNC_ACT_EOF */		"end-of-frame-mark",
106 	/* PFSYNC_ACT_INS_1400 */	"state-insert",
107 	/* PFSYNC_ACT_UPD_1400 */	"state-update",
108 };
109 
110 static void
111 pfsync_acts_stats(const char *list, const char *desc, uint64_t *a)
112 {
113 	int i;
114 
115 	xo_open_list(list);
116 	for (i = 0; i < PFSYNC_ACT_MAX; i++, a++) {
117 		if (*a || sflag <= 1) {
118 			xo_open_instance(list);
119 			xo_emit("\t\t{e:name}{:count/%ju} {N:/%s%s %s}\n",
120 			    pfsyncacts_name[i], (uintmax_t)(*a),
121 			    pfsyncacts[i], plural(*a), desc);
122 			xo_close_instance(list);
123 		}
124 	}
125 	xo_close_list(list);
126 }
127 
128 /*
129  * Dump pfsync statistics structure.
130  */
131 void
132 pfsync_stats(u_long off, const char *name, int af1 __unused, int proto __unused)
133 {
134 	struct pfsyncstats pfsyncstat;
135 
136 	if (fetch_stats("net.pfsync.stats", off, &pfsyncstat,
137 	    sizeof(pfsyncstat), kread) != 0)
138 		return;
139 
140 	xo_emit("{T:/%s}:\n", name);
141 	xo_open_container(name);
142 
143 #define	p(f, m) if (pfsyncstat.f || sflag <= 1) \
144 	xo_emit(m, (uintmax_t)pfsyncstat.f, plural(pfsyncstat.f))
145 
146 	p(pfsyncs_ipackets, "\t{:received-inet-packets/%ju} "
147 	    "{N:/packet%s received (IPv4)}\n");
148 	p(pfsyncs_ipackets6, "\t{:received-inet6-packets/%ju} "
149 	    "{N:/packet%s received (IPv6)}\n");
150 	pfsync_acts_stats("input-histogram", "received",
151 	    &pfsyncstat.pfsyncs_iacts[0]);
152 	p(pfsyncs_badif, "\t\t{:dropped-bad-interface/%ju} "
153 	    "{N:/packet%s discarded for bad interface}\n");
154 	p(pfsyncs_badttl, "\t\t{:dropped-bad-ttl/%ju} "
155 	    "{N:/packet%s discarded for bad ttl}\n");
156 	p(pfsyncs_hdrops, "\t\t{:dropped-short-header/%ju} "
157 	    "{N:/packet%s shorter than header}\n");
158 	p(pfsyncs_badver, "\t\t{:dropped-bad-version/%ju} "
159 	    "{N:/packet%s discarded for bad version}\n");
160 	p(pfsyncs_badauth, "\t\t{:dropped-bad-auth/%ju} "
161 	    "{N:/packet%s discarded for bad HMAC}\n");
162 	p(pfsyncs_badact,"\t\t{:dropped-bad-action/%ju} "
163 	    "{N:/packet%s discarded for bad action}\n");
164 	p(pfsyncs_badlen, "\t\t{:dropped-short/%ju} "
165 	    "{N:/packet%s discarded for short packet}\n");
166 	p(pfsyncs_badval, "\t\t{:dropped-bad-values/%ju} "
167 	    "{N:/state%s discarded for bad values}\n");
168 	p(pfsyncs_stale, "\t\t{:dropped-stale-state/%ju} "
169 	    "{N:/stale state%s}\n");
170 	p(pfsyncs_badstate, "\t\t{:dropped-failed-lookup/%ju} "
171 	    "{N:/failed state lookup\\/insert%s}\n");
172 	p(pfsyncs_opackets, "\t{:sent-inet-packets/%ju} "
173 	    "{N:/packet%s sent (IPv4})\n");
174 	p(pfsyncs_opackets6, "\t{:send-inet6-packets/%ju} "
175 	    "{N:/packet%s sent (IPv6})\n");
176 	pfsync_acts_stats("output-histogram", "sent",
177 	    &pfsyncstat.pfsyncs_oacts[0]);
178 	p(pfsyncs_onomem, "\t\t{:discarded-no-memory/%ju} "
179 	    "{N:/failure%s due to mbuf memory error}\n");
180 	p(pfsyncs_oerrors, "\t\t{:send-errors/%ju} "
181 	    "{N:/send error%s}\n");
182 #undef p
183 	xo_close_container(name);
184 }
185 
186 void
187 pflow_stats(u_long off, const char *name, int af1 __unused, int proto __unused)
188 {
189 	struct pflowstats pflowstat;
190 
191 	if (fetch_stats("net.pflow.stats", off, &pflowstat,
192 	    sizeof(pflowstat), kread) != 0)
193 		return;
194 
195 	xo_emit("{T:/%s}:\n", name);
196 	xo_open_container(name);
197 
198 #define	p(f, m) if (pflowstat.f || sflag <= 1) \
199 	xo_emit(m, (uintmax_t)pflowstat.f, plural(pflowstat.f))
200 
201 	p(pflow_flows, "\t{:flows/%ju} {N:/flow%s sent}\n");
202 	p(pflow_packets, "\t{:packets/%ju} {N:/packet%s sent}\n");
203 	p(pflow_onomem, "\t{:nomem/%ju} "
204 	    "{N:/send failed due to mbuf memory error}\n");
205 	p(pflow_oerrors, "\t{:send-error/%ju} {N:/send error}\n");
206 #undef p
207 
208 	xo_close_container(name);
209 }
210 #endif /* PF */
211 
212 /*
213  * Display a formatted value, or a '-' in the same space.
214  */
215 static void
216 show_stat(const char *fmt, int width, const char *name,
217     u_long value, short showvalue, int div1000)
218 {
219 	const char *lsep, *rsep;
220 	char newfmt[64];
221 
222 	lsep = "";
223 	if (strncmp(fmt, "LS", 2) == 0) {
224 		lsep = " ";
225 		fmt += 2;
226 	}
227 	rsep = " ";
228 	if (strncmp(fmt, "NRS", 3) == 0) {
229 		rsep = "";
230 		fmt += 3;
231 	}
232 	if (showvalue == 0) {
233 		/* Print just dash. */
234 		xo_emit("{P:/%s}{D:/%*s}{P:/%s}", lsep, width, "-", rsep);
235 		return;
236 	}
237 
238 	/*
239 	 * XXX: workaround {P:} modifier can't be empty and doesn't seem to
240 	 * take args... so we need to conditionally include it in the format.
241 	 */
242 #define maybe_pad(pad)	do {						    \
243 	if (strlen(pad)) {						    \
244 		snprintf(newfmt, sizeof(newfmt), "{P:%s}", pad);	    \
245 		xo_emit(newfmt);					    \
246 	}								    \
247 } while (0)
248 
249 	if (hflag) {
250 		char buf[5];
251 
252 		/* Format in human readable form. */
253 		humanize_number(buf, sizeof(buf), (int64_t)value, "",
254 		    HN_AUTOSCALE, HN_NOSPACE | HN_DECIMAL | \
255 		    ((div1000) ? HN_DIVISOR_1000 : 0));
256 		maybe_pad(lsep);
257 		snprintf(newfmt, sizeof(newfmt), "{:%s/%%%ds}", name, width);
258 		xo_emit(newfmt, buf);
259 		maybe_pad(rsep);
260 	} else {
261 		/* Construct the format string. */
262 		maybe_pad(lsep);
263 		snprintf(newfmt, sizeof(newfmt), "{:%s/%%%d%s}",
264 		    name, width, fmt);
265 		xo_emit(newfmt, value);
266 		maybe_pad(rsep);
267 	}
268 }
269 
270 /*
271  * Find next multiaddr for a given interface name.
272  */
273 static struct ifmaddrs *
274 next_ifma(struct ifmaddrs *ifma, const char *name, const sa_family_t family)
275 {
276 
277 	for(; ifma != NULL; ifma = ifma->ifma_next) {
278 		struct sockaddr_dl *sdl;
279 
280 		sdl = (struct sockaddr_dl *)ifma->ifma_name;
281 		if (ifma->ifma_addr->sa_family == family &&
282 		    strcmp(sdl->sdl_data, name) == 0)
283 			break;
284 	}
285 
286 	return (ifma);
287 }
288 
289 enum process_op { MEASURE, EMIT };
290 
291 static void
292 process_ifa_addr(enum process_op op, struct ifaddrs *ifa, int *max_net_len,
293     int *max_addr_len, bool *network, bool *link)
294 {
295 	int net_len, addr_len;
296 	const char *nn, *rn;
297 
298 	if (op == EMIT) {
299 		net_len = *max_net_len;
300 		addr_len = *max_addr_len;
301 	}
302 
303 	switch (ifa->ifa_addr->sa_family) {
304 	case AF_UNSPEC:
305 		if (op == MEASURE) {
306 			net_len = strlen("none");
307 			addr_len = strlen("none");
308 		} else {
309 			xo_emit("{:network/%-*.*s}  ", net_len, net_len,
310 			    "none");
311 			xo_emit("{:address/%-*.*s} ", addr_len, addr_len,
312 			    "none");
313 		}
314 		break;
315 	case AF_INET:
316 #ifdef INET6
317 	case AF_INET6:
318 #endif /* INET6 */
319 		nn = netname(ifa->ifa_addr, ifa->ifa_netmask);
320 		rn = routename(ifa->ifa_addr, numeric_addr);
321 		if (op == MEASURE) {
322 			net_len = strlen(nn);
323 			addr_len = strlen(rn);
324 		} else {
325 			xo_emit("{t:network/%-*s}  ", net_len, nn);
326 			xo_emit("{t:address/%-*s} ", addr_len, rn);
327 		}
328 
329 		if (network != NULL)
330 			*network = true;
331 		break;
332 	case AF_LINK:
333 	    {
334 		struct sockaddr_dl *sdl;
335 		char linknum[sizeof("<Link#32767>")];
336 
337 		sdl = (struct sockaddr_dl *)ifa->ifa_addr;
338 		snprintf(linknum, sizeof(linknum), "<Link#%d>", sdl->sdl_index);
339 		if (op == MEASURE) {
340 			net_len = strlen(linknum);
341 			if (sdl->sdl_nlen == 0 &&
342 			    sdl->sdl_alen == 0 &&
343 			    sdl->sdl_slen == 0)
344 				addr_len = 1;
345 			else
346 				addr_len = strlen(routename(ifa->ifa_addr, 1));
347 		} else {
348 			xo_emit("{t:network/%-*.*s}  ", net_len, net_len,
349 			    linknum);
350 			if (sdl->sdl_nlen == 0 &&
351 			    sdl->sdl_alen == 0 &&
352 			    sdl->sdl_slen == 0)
353 				xo_emit("{P:/%*s} ", addr_len, "");
354 			else
355 				xo_emit("{t:address/%-*.*s} ", addr_len,
356 				    addr_len, routename(ifa->ifa_addr, 1));
357 		}
358 		if (link != NULL)
359 			*link = true;
360 		break;
361 	    }
362 	}
363 
364 	if (op == MEASURE) {
365 		if (net_len > *max_net_len)
366 			*max_net_len = net_len;
367 		if (addr_len > *max_addr_len)
368 			*max_addr_len = addr_len;
369 	}
370 }
371 
372 static int
373 max_num_len(int max_len, u_long num)
374 {
375 	int len = 2;		/* include space */
376 
377 	for (; num > 10; len++)
378 		num /= 10;
379 	return (MAX(max_len, len));
380 }
381 
382 /*
383  * Print a description of the network interfaces.
384  */
385 void
386 intpr(void (*pfunc)(char *), int af)
387 {
388 	struct ifaddrs *ifap, *ifa;
389 	struct ifmaddrs *ifmap, *ifma;
390 	u_int ifn_len_max = 5, ifn_len;
391 	u_int net_len = strlen("Network "), addr_len = strlen("Address ");
392 	u_int npkt_len = 8, nbyte_len = 10, nerr_len = 5;
393 
394 	if (interval)
395 		return sidewaysintpr();
396 
397 	if (getifaddrs(&ifap) != 0)
398 		err(EX_OSERR, "getifaddrs");
399 	if (aflag && getifmaddrs(&ifmap) != 0)
400 		err(EX_OSERR, "getifmaddrs");
401 
402 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
403 		if (interface != NULL &&
404 		    strcmp(ifa->ifa_name, interface) != 0)
405 			continue;
406 		if (af != AF_UNSPEC && ifa->ifa_addr->sa_family != af)
407 			continue;
408 		ifn_len = strlen(ifa->ifa_name);
409 		if ((ifa->ifa_flags & IFF_UP) == 0)
410 			++ifn_len;
411 		ifn_len_max = MAX(ifn_len_max, ifn_len);
412 		process_ifa_addr(MEASURE, ifa, &net_len, &addr_len,
413 		    NULL, NULL);
414 
415 #define	IFA_STAT(s)	(((struct if_data *)ifa->ifa_data)->ifi_ ## s)
416 		if (!hflag) {
417 			npkt_len = max_num_len(npkt_len, IFA_STAT(ipackets));
418 			npkt_len = max_num_len(npkt_len, IFA_STAT(opackets));
419 			nerr_len = max_num_len(nerr_len, IFA_STAT(ierrors));
420 			nerr_len = max_num_len(nerr_len, IFA_STAT(iqdrops));
421 			nerr_len = max_num_len(nerr_len, IFA_STAT(collisions));
422 			if (dflag)
423 				nerr_len = max_num_len(nerr_len,
424 				    IFA_STAT(oqdrops));
425 			if (bflag) {
426 				nbyte_len = max_num_len(nbyte_len,
427 				    IFA_STAT(ibytes));
428 				nbyte_len = max_num_len(nbyte_len,
429 				    IFA_STAT(obytes));
430 			}
431 		}
432 	}
433 
434 	xo_open_list("interface");
435 	if (!pfunc) {
436 		xo_emit("{T:/%-*.*s}", ifn_len_max, ifn_len_max, "Name");
437 		xo_emit(" {T:/%5.5s} {T:/%-*.*s}  {T:/%-*.*s} {T:/%*.*s} "
438 		    "{T:/%*.*s} {T:/%*.*s}",
439 		    "Mtu", net_len, net_len, "Network", addr_len, addr_len,
440 		    "Address", npkt_len, npkt_len, "Ipkts",
441 		    nerr_len, nerr_len, "Ierrs", nerr_len, nerr_len, "Idrop");
442 		if (bflag)
443 			xo_emit(" {T:/%*.*s}", nbyte_len, nbyte_len, "Ibytes");
444 		xo_emit(" {T:/%*.*s} {T:/%*.*s}", npkt_len, npkt_len, "Opkts",
445 		    nerr_len, nerr_len, "Oerrs");
446 		if (bflag)
447 			xo_emit(" {T:/%*.*s}", nbyte_len, nbyte_len, "Obytes");
448 		xo_emit(" {T:/%*s}", nerr_len, "Coll");
449 		if (dflag)
450 			xo_emit(" {T:/%*.*s}", nerr_len, nerr_len, "Drop");
451 		xo_emit("\n");
452 	}
453 
454 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
455 		bool network = false, link = false;
456 		char *name, *xname, buf[IFNAMSIZ+1];
457 
458 		if (interface != NULL && strcmp(ifa->ifa_name, interface) != 0)
459 			continue;
460 
461 		name = ifa->ifa_name;
462 
463 		if (pfunc) {
464 
465 			(*pfunc)(name);
466 
467 			/*
468 			 * Skip all ifaddrs belonging to same interface.
469 			 */
470 			while(ifa->ifa_next != NULL &&
471 			    (strcmp(ifa->ifa_next->ifa_name, name) == 0)) {
472 				ifa = ifa->ifa_next;
473 			}
474 			continue;
475 		}
476 
477 		if (af != AF_UNSPEC && ifa->ifa_addr->sa_family != af)
478 			continue;
479 
480 		xo_open_instance("interface");
481 
482 		if ((ifa->ifa_flags & IFF_UP) == 0) {
483 			xname = stpcpy(buf, name);
484 			*xname++ = '*';
485 			*xname = '\0';
486 			xname = buf;
487 		} else
488 			xname = name;
489 
490 		xo_emit("{d:/%-*.*s}{etk:name}{eq:flags/0x%x}",
491 		    ifn_len_max, ifn_len_max, xname, name, ifa->ifa_flags);
492 
493 #define IFA_MTU(ifa)	(((struct if_data *)(ifa)->ifa_data)->ifi_mtu)
494 		show_stat("lu", 6, "mtu", IFA_MTU(ifa), IFA_MTU(ifa), 0);
495 #undef IFA_MTU
496 
497 		process_ifa_addr(EMIT, ifa, &net_len, &addr_len,
498 		    &network, &link);
499 
500 		show_stat("lu", npkt_len, "received-packets",
501 		    IFA_STAT(ipackets), link|network, 1);
502 		show_stat("lu", nerr_len, "received-errors", IFA_STAT(ierrors),
503 		    link, 1);
504 		show_stat("lu", nerr_len, "dropped-packets", IFA_STAT(iqdrops),
505 		    link, 1);
506 		if (bflag)
507 			show_stat("lu", nbyte_len, "received-bytes",
508 			    IFA_STAT(ibytes), link|network, 0);
509 		show_stat("lu", npkt_len, "sent-packets", IFA_STAT(opackets),
510 		    link|network, 1);
511 		show_stat("lu", nerr_len, "send-errors", IFA_STAT(oerrors),
512 		    link, 1);
513 		if (bflag)
514 			show_stat("lu", nbyte_len, "sent-bytes",
515 			    IFA_STAT(obytes), link|network, 0);
516 		show_stat("NRSlu", nerr_len, "collisions", IFA_STAT(collisions),
517 		    link, 1);
518 		if (dflag)
519 			show_stat("LSlu", nerr_len, "dropped-packets",
520 			    IFA_STAT(oqdrops), link, 1);
521 		xo_emit("\n");
522 
523 		if (!aflag) {
524 			xo_close_instance("interface");
525 			continue;
526 		}
527 
528 		/*
529 		 * Print family's multicast addresses.
530 		 */
531 		xo_open_list("multicast-address");
532 		for (ifma = next_ifma(ifmap, ifa->ifa_name,
533 		    ifa->ifa_addr->sa_family);
534 		    ifma != NULL;
535 		    ifma = next_ifma(ifma, ifa->ifa_name,
536 		    ifa->ifa_addr->sa_family)) {
537 			const char *fmt = NULL;
538 
539 			xo_open_instance("multicast-address");
540 			switch (ifma->ifma_addr->sa_family) {
541 			case AF_LINK:
542 			    {
543 				struct sockaddr_dl *sdl;
544 
545 				sdl = (struct sockaddr_dl *)ifma->ifma_addr;
546 				if (sdl->sdl_type != IFT_ETHER &&
547 				    sdl->sdl_type != IFT_FDDI)
548 					break;
549 			    }
550 				/* FALLTHROUGH */
551 			case AF_INET:
552 #ifdef INET6
553 			case AF_INET6:
554 #endif /* INET6 */
555 				fmt = routename(ifma->ifma_addr, numeric_addr);
556 				break;
557 			}
558 			if (fmt) {
559 				if (Wflag)
560 					xo_emit("{P:/%27s }"
561 					    "{t:address/%-17s/}", "", fmt);
562 				else
563 					xo_emit("{P:/%25s }"
564 					    "{t:address/%-17.17s/}", "", fmt);
565 				if (ifma->ifma_addr->sa_family == AF_LINK) {
566 					xo_emit(" {:received-packets/%8lu}",
567 					    IFA_STAT(imcasts));
568 					xo_emit("{P:/%*s}", bflag? 17 : 6, "");
569 					xo_emit(" {:sent-packets/%8lu}",
570 					    IFA_STAT(omcasts));
571  				}
572 				xo_emit("\n");
573 			}
574 			xo_close_instance("multicast-address");
575 			ifma = ifma->ifma_next;
576 		}
577 		xo_close_list("multicast-address");
578 		xo_close_instance("interface");
579 	}
580 	xo_close_list("interface");
581 
582 	freeifaddrs(ifap);
583 	if (aflag)
584 		freeifmaddrs(ifmap);
585 }
586 
587 struct iftot {
588 	u_long	ift_ip;			/* input packets */
589 	u_long	ift_ie;			/* input errors */
590 	u_long	ift_id;			/* input drops */
591 	u_long	ift_op;			/* output packets */
592 	u_long	ift_oe;			/* output errors */
593 	u_long	ift_od;			/* output drops */
594 	u_long	ift_co;			/* collisions */
595 	u_long	ift_ib;			/* input bytes */
596 	u_long	ift_ob;			/* output bytes */
597 };
598 
599 /*
600  * Obtain stats for interface(s).
601  */
602 static void
603 fill_iftot(struct iftot *st)
604 {
605 	struct ifaddrs *ifap, *ifa;
606 	bool found = false;
607 
608 	if (getifaddrs(&ifap) != 0)
609 		xo_err(EX_OSERR, "getifaddrs");
610 
611 	bzero(st, sizeof(*st));
612 
613 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
614 		if (ifa->ifa_addr->sa_family != AF_LINK)
615 			continue;
616 		if (interface) {
617 			if (strcmp(ifa->ifa_name, interface) == 0)
618 				found = true;
619 			else
620 				continue;
621 		}
622 
623 		st->ift_ip += IFA_STAT(ipackets);
624 		st->ift_ie += IFA_STAT(ierrors);
625 		st->ift_id += IFA_STAT(iqdrops);
626 		st->ift_ib += IFA_STAT(ibytes);
627 		st->ift_op += IFA_STAT(opackets);
628 		st->ift_oe += IFA_STAT(oerrors);
629 		st->ift_od += IFA_STAT(oqdrops);
630 		st->ift_ob += IFA_STAT(obytes);
631  		st->ift_co += IFA_STAT(collisions);
632 	}
633 
634 	if (interface && found == false)
635 		xo_err(EX_DATAERR, "interface %s not found", interface);
636 
637 	freeifaddrs(ifap);
638 }
639 
640 /*
641  * Set a flag to indicate that a signal from the periodic itimer has been
642  * caught.
643  */
644 static sig_atomic_t signalled;
645 static void
646 catchalarm(int signo __unused)
647 {
648 	signalled = true;
649 }
650 
651 /*
652  * Print a running summary of interface statistics.
653  * Repeat display every interval seconds, showing statistics
654  * collected over that interval.  Assumes that interval is non-zero.
655  * First line printed at top of screen is always cumulative.
656  */
657 static void
658 sidewaysintpr(void)
659 {
660 	struct iftot ift[2], *new, *old;
661 	struct itimerval interval_it;
662 	int oldmask, line;
663 
664 	new = &ift[0];
665 	old = &ift[1];
666 	fill_iftot(old);
667 
668 	(void)signal(SIGALRM, catchalarm);
669 	signalled = false;
670 	interval_it.it_interval.tv_sec = interval;
671 	interval_it.it_interval.tv_usec = 0;
672 	interval_it.it_value = interval_it.it_interval;
673 	setitimer(ITIMER_REAL, &interval_it, NULL);
674 	xo_open_list("interface-statistics");
675 
676 banner:
677 	xo_emit("{T:/%17s} {T:/%14s} {T:/%16s}\n", "input",
678 	    interface != NULL ? interface : "(Total)", "output");
679 	xo_emit("{T:/%10s} {T:/%5s} {T:/%5s} {T:/%10s} {T:/%10s} {T:/%5s} "
680 	    "{T:/%10s} {T:/%5s}",
681 	    "packets", "errs", "idrops", "bytes", "packets", "errs", "bytes",
682 	    "colls");
683 	if (dflag)
684 		xo_emit(" {T:/%5.5s}", "drops");
685 	xo_emit("\n");
686 	xo_flush();
687 	line = 0;
688 
689 loop:
690 	if ((noutputs != 0) && (--noutputs == 0)) {
691 		xo_close_list("interface-statistics");
692 		return;
693 	}
694 	oldmask = sigblock(sigmask(SIGALRM));
695 	while (!signalled)
696 		sigpause(0);
697 	signalled = false;
698 	sigsetmask(oldmask);
699 	line++;
700 
701 	fill_iftot(new);
702 
703 	xo_open_instance("stats");
704 	show_stat("lu", 10, "received-packets",
705 	    new->ift_ip - old->ift_ip, 1, 1);
706 	show_stat("lu", 5, "received-errors",
707 	    new->ift_ie - old->ift_ie, 1, 1);
708 	show_stat("lu", 5, "dropped-packets",
709 	    new->ift_id - old->ift_id, 1, 1);
710 	show_stat("lu", 10, "received-bytes",
711 	    new->ift_ib - old->ift_ib, 1, 0);
712 	show_stat("lu", 10, "sent-packets",
713 	    new->ift_op - old->ift_op, 1, 1);
714 	show_stat("lu", 5, "send-errors",
715 	    new->ift_oe - old->ift_oe, 1, 1);
716 	show_stat("lu", 10, "sent-bytes",
717 	    new->ift_ob - old->ift_ob, 1, 0);
718 	show_stat("NRSlu", 5, "collisions",
719 	    new->ift_co - old->ift_co, 1, 1);
720 	if (dflag)
721 		show_stat("LSlu", 5, "dropped-packets",
722 		    new->ift_od - old->ift_od, 1, 1);
723 	xo_close_instance("stats");
724 	xo_emit("\n");
725 	xo_flush();
726 
727 	if (new == &ift[0]) {
728 		new = &ift[1];
729 		old = &ift[0];
730 	} else {
731 		new = &ift[0];
732 		old = &ift[1];
733 	}
734 
735 	if (line == 21)
736 		goto banner;
737 	else
738 		goto loop;
739 
740 	/* NOTREACHED */
741 }
742