xref: /freebsd/usr.bin/netstat/if.c (revision 4f29da19bd44f0e99f021510460a81bf754c21d2)
1 /*
2  * Copyright (c) 1983, 1988, 1993
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 the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #if 0
35 #ifndef lint
36 static char sccsid[] = "@(#)if.c	8.3 (Berkeley) 4/28/95";
37 #endif /* not lint */
38 #endif
39 
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD$");
42 
43 #include <sys/types.h>
44 #include <sys/protosw.h>
45 #include <sys/socket.h>
46 #include <sys/sysctl.h>
47 #include <sys/time.h>
48 
49 #include <net/if.h>
50 #include <net/if_var.h>
51 #include <net/if_dl.h>
52 #include <net/if_types.h>
53 #include <net/ethernet.h>
54 #include <net/pfvar.h>
55 #include <net/if_pfsync.h>
56 #include <netinet/in.h>
57 #include <netinet/in_var.h>
58 #include <netipx/ipx.h>
59 #include <netipx/ipx_if.h>
60 #include <arpa/inet.h>
61 
62 #include <err.h>
63 #include <errno.h>
64 #include <libutil.h>
65 #include <signal.h>
66 #include <stdio.h>
67 #include <stdlib.h>
68 #include <string.h>
69 #include <unistd.h>
70 
71 #include "netstat.h"
72 
73 #define	YES	1
74 #define	NO	0
75 
76 static void sidewaysintpr (u_int, u_long);
77 static void catchalarm (int);
78 
79 #ifdef INET6
80 static char ntop_buf[INET6_ADDRSTRLEN];		/* for inet_ntop() */
81 #endif
82 
83 /*
84  * Dump pfsync statistics structure.
85  */
86 void
87 pfsync_stats(u_long off __unused, const char *name, int af1 __unused)
88 {
89 	struct pfsyncstats pfsyncstat, zerostat;
90 	size_t len = sizeof(struct pfsyncstats);
91 
92 	if (zflag)
93 		memset(&zerostat, 0, len);
94 	if (sysctlbyname("net.inet.pfsync.stats", &pfsyncstat, &len,
95 	    zflag ? &zerostat : NULL, zflag ? len : 0) < 0) {
96 		if (errno != ENOENT)
97 			warn("sysctl: net.inet.pfsync.stats");
98 		return;
99 	}
100 
101 	printf("%s:\n", name);
102 
103 #define p(f, m) if (pfsyncstat.f || sflag <= 1) \
104 	printf(m, (unsigned long long)pfsyncstat.f, plural(pfsyncstat.f))
105 #define p2(f, m) if (pfsyncstat.f || sflag <= 1) \
106 	printf(m, (unsigned long long)pfsyncstat.f)
107 
108 	p(pfsyncs_ipackets, "\t%llu packet%s received (IPv4)\n");
109 	p(pfsyncs_ipackets6, "\t%llu packet%s received (IPv6)\n");
110 	p(pfsyncs_badif, "\t\t%llu packet%s discarded for bad interface\n");
111 	p(pfsyncs_badttl, "\t\t%llu packet%s discarded for bad ttl\n");
112 	p(pfsyncs_hdrops, "\t\t%llu packet%s shorter than header\n");
113 	p(pfsyncs_badver, "\t\t%llu packet%s discarded for bad version\n");
114 	p(pfsyncs_badauth, "\t\t%llu packet%s discarded for bad HMAC\n");
115 	p(pfsyncs_badact,"\t\t%llu packet%s discarded for bad action\n");
116 	p(pfsyncs_badlen, "\t\t%llu packet%s discarded for short packet\n");
117 	p(pfsyncs_badval, "\t\t%llu state%s discarded for bad values\n");
118 	p(pfsyncs_stale, "\t\t%llu stale state%s\n");
119 	p(pfsyncs_badstate, "\t\t%llu failed state lookup/insert%s\n");
120 	p(pfsyncs_opackets, "\t%llu packet%s sent (IPv4)\n");
121 	p(pfsyncs_opackets6, "\t%llu packet%s sent (IPv6)\n");
122 	p2(pfsyncs_onomem, "\t\t%llu send failed due to mbuf memory error\n");
123 	p2(pfsyncs_oerrors, "\t\t%llu send error\n");
124 #undef p
125 #undef p2
126 }
127 
128 /*
129  * Display a formatted value, or a '-' in the same space.
130  */
131 static void
132 show_stat(const char *fmt, int width, u_long value, short showvalue)
133 {
134 	char newfmt[32];
135 
136 	if (showvalue == 0) {
137 		/* Print just dash. */
138 		sprintf(newfmt, "%%%ds ", width);
139 		printf(newfmt, "-");
140 		return;
141 	}
142 
143 	if (hflag) {
144 		char buf[5];
145 
146 		/* Format in human readable form. */
147 		humanize_number(buf, sizeof(buf), (int64_t)value, "",
148 		    HN_AUTOSCALE, HN_NOSPACE | HN_DECIMAL);
149 		sprintf(newfmt, "%%%ds ", width);
150 		printf(newfmt, buf);
151 	} else {
152 		/* Construct the format string. */
153 		sprintf(newfmt, "%%%d%s ", width, fmt);
154 		printf(newfmt, value);
155 	}
156 }
157 
158 /*
159  * Print a description of the network interfaces.
160  */
161 void
162 intpr(int _interval, u_long ifnetaddr, void (*pfunc)(char *))
163 {
164 	struct ifnet ifnet;
165 	struct ifnethead ifnethead;
166 	union {
167 		struct ifaddr ifa;
168 		struct in_ifaddr in;
169 #ifdef INET6
170 		struct in6_ifaddr in6;
171 #endif
172 		struct ipx_ifaddr ipx;
173 	} ifaddr;
174 	u_long ifaddraddr;
175 	u_long ifaddrfound;
176 	u_long ifnetfound;
177 	u_long opackets;
178 	u_long ipackets;
179 	u_long obytes;
180 	u_long ibytes;
181 	u_long omcasts;
182 	u_long imcasts;
183 	u_long oerrors;
184 	u_long ierrors;
185 	u_long collisions;
186 	short timer;
187 	int drops;
188 	struct sockaddr *sa = NULL;
189 	char name[IFNAMSIZ];
190 	short network_layer;
191 	short link_layer;
192 
193 	if (ifnetaddr == 0) {
194 		printf("ifnet: symbol not defined\n");
195 		return;
196 	}
197 	if (_interval) {
198 		sidewaysintpr((unsigned)_interval, ifnetaddr);
199 		return;
200 	}
201 	if (kread(ifnetaddr, (char *)&ifnethead, sizeof ifnethead))
202 		return;
203 	ifnetaddr = (u_long)TAILQ_FIRST(&ifnethead);
204 	if (kread(ifnetaddr, (char *)&ifnet, sizeof ifnet))
205 		return;
206 
207 	if (!pfunc) {
208 		if (Wflag)
209 			printf("%-7.7s", "Name");
210 		else
211 			printf("%-5.5s", "Name");
212 		printf(" %5.5s %-13.13s %-17.17s %8.8s %5.5s",
213 		    "Mtu", "Network", "Address", "Ipkts", "Ierrs");
214 		if (bflag)
215 			printf(" %10.10s","Ibytes");
216 		printf(" %8.8s %5.5s", "Opkts", "Oerrs");
217 		if (bflag)
218 			printf(" %10.10s","Obytes");
219 		printf(" %5s", "Coll");
220 		if (tflag)
221 			printf(" %s", "Time");
222 		if (dflag)
223 			printf(" %s", "Drop");
224 		putchar('\n');
225 	}
226 	ifaddraddr = 0;
227 	while (ifnetaddr || ifaddraddr) {
228 		struct sockaddr_in *sockin;
229 #ifdef INET6
230 		struct sockaddr_in6 *sockin6;
231 #endif
232 		char *cp;
233 		int n, m;
234 
235 		network_layer = 0;
236 		link_layer = 0;
237 
238 		if (ifaddraddr == 0) {
239 			ifnetfound = ifnetaddr;
240 			if (kread(ifnetaddr, (char *)&ifnet, sizeof ifnet))
241 				return;
242 			strlcpy(name, ifnet.if_xname, sizeof(name));
243 			ifnetaddr = (u_long)TAILQ_NEXT(&ifnet, if_link);
244 			if (interface != 0 && (strcmp(name, interface) != 0))
245 				continue;
246 			cp = index(name, '\0');
247 
248 			if (pfunc) {
249 				(*pfunc)(name);
250 				continue;
251 			}
252 
253 			if ((ifnet.if_flags&IFF_UP) == 0)
254 				*cp++ = '*';
255 			*cp = '\0';
256 			ifaddraddr = (u_long)TAILQ_FIRST(&ifnet.if_addrhead);
257 		}
258 		ifaddrfound = ifaddraddr;
259 
260 		/*
261 		 * Get the interface stats.  These may get
262 		 * overriden below on a per-interface basis.
263 		 */
264 		opackets = ifnet.if_opackets;
265 		ipackets = ifnet.if_ipackets;
266 		obytes = ifnet.if_obytes;
267 		ibytes = ifnet.if_ibytes;
268 		omcasts = ifnet.if_omcasts;
269 		imcasts = ifnet.if_imcasts;
270 		oerrors = ifnet.if_oerrors;
271 		ierrors = ifnet.if_ierrors;
272 		collisions = ifnet.if_collisions;
273 		timer = ifnet.if_timer;
274 		drops = ifnet.if_snd.ifq_drops;
275 
276 		if (ifaddraddr == 0) {
277 			if (Wflag)
278 				printf("%-7.7s", name);
279 			else
280 				printf("%-5.5s", name);
281 			printf(" %5lu ", ifnet.if_mtu);
282 			printf("%-13.13s ", "none");
283 			printf("%-17.17s ", "none");
284 		} else {
285 			if (kread(ifaddraddr, (char *)&ifaddr, sizeof ifaddr)) {
286 				ifaddraddr = 0;
287 				continue;
288 			}
289 #define CP(x) ((char *)(x))
290 			cp = (CP(ifaddr.ifa.ifa_addr) - CP(ifaddraddr)) +
291 				CP(&ifaddr);
292 			sa = (struct sockaddr *)cp;
293 			if (af != AF_UNSPEC && sa->sa_family != af) {
294 				ifaddraddr =
295 				    (u_long)TAILQ_NEXT(&ifaddr.ifa, ifa_link);
296 				continue;
297 			}
298 			if (Wflag)
299 				printf("%-7.7s", name);
300 			else
301 				printf("%-5.5s", name);
302 			printf(" %5lu ", ifnet.if_mtu);
303 			switch (sa->sa_family) {
304 			case AF_UNSPEC:
305 				printf("%-13.13s ", "none");
306 				printf("%-15.15s ", "none");
307 				break;
308 			case AF_INET:
309 				sockin = (struct sockaddr_in *)sa;
310 #ifdef notdef
311 				/* can't use inet_makeaddr because kernel
312 				 * keeps nets unshifted.
313 				 */
314 				in = inet_makeaddr(ifaddr.in.ia_subnet,
315 					INADDR_ANY);
316 				printf("%-13.13s ", netname(in.s_addr,
317 				    ifaddr.in.ia_subnetmask));
318 #else
319 				printf("%-13.13s ",
320 				    netname(htonl(ifaddr.in.ia_subnet),
321 				    ifaddr.in.ia_subnetmask));
322 #endif
323 				printf("%-17.17s ",
324 				    routename(sockin->sin_addr.s_addr));
325 
326 				network_layer = 1;
327 				break;
328 #ifdef INET6
329 			case AF_INET6:
330 				sockin6 = (struct sockaddr_in6 *)sa;
331 				printf("%-13.13s ",
332 				       netname6(&ifaddr.in6.ia_addr,
333 						&ifaddr.in6.ia_prefixmask.sin6_addr));
334 				printf("%-17.17s ",
335 				    inet_ntop(AF_INET6,
336 					&sockin6->sin6_addr,
337 					ntop_buf, sizeof(ntop_buf)));
338 
339 				network_layer = 1;
340 				break;
341 #endif /*INET6*/
342 			case AF_IPX:
343 				{
344 				struct sockaddr_ipx *sipx =
345 					(struct sockaddr_ipx *)sa;
346 				u_long net;
347 				char netnum[10];
348 
349 				*(union ipx_net *) &net = sipx->sipx_addr.x_net;
350 				sprintf(netnum, "%lx", (u_long)ntohl(net));
351 				printf("ipx:%-8s  ", netnum);
352 /*				printf("ipx:%-8s ", netname(net, 0L)); */
353 				printf("%-17s ",
354 				    ipx_phost((struct sockaddr *)sipx));
355 				}
356 
357 				network_layer = 1;
358 				break;
359 
360 			case AF_APPLETALK:
361 				printf("atalk:%-12.12s ",atalk_print(sa,0x10) );
362 				printf("%-11.11s  ",atalk_print(sa,0x0b) );
363 				break;
364 			case AF_LINK:
365 				{
366 				struct sockaddr_dl *sdl =
367 					(struct sockaddr_dl *)sa;
368 				char linknum[10];
369 				cp = (char *)LLADDR(sdl);
370 				n = sdl->sdl_alen;
371 				sprintf(linknum, "<Link#%d>", sdl->sdl_index);
372 				m = printf("%-13.13s ", linknum);
373 				}
374 				goto hexprint;
375 			default:
376 				m = printf("(%d)", sa->sa_family);
377 				for (cp = sa->sa_len + (char *)sa;
378 					--cp > sa->sa_data && (*cp == 0);) {}
379 				n = cp - sa->sa_data + 1;
380 				cp = sa->sa_data;
381 			hexprint:
382 				while (--n >= 0)
383 					m += printf("%02x%c", *cp++ & 0xff,
384 						    n > 0 ? ':' : ' ');
385 				m = 32 - m;
386 				while (m-- > 0)
387 					putchar(' ');
388 
389 				link_layer = 1;
390 				break;
391 			}
392 
393 			/*
394 			 * Fixup the statistics for interfaces that
395 			 * update stats for their network addresses
396 			 */
397 			if (network_layer) {
398 				opackets = ifaddr.in.ia_ifa.if_opackets;
399 				ipackets = ifaddr.in.ia_ifa.if_ipackets;
400 				obytes = ifaddr.in.ia_ifa.if_obytes;
401 				ibytes = ifaddr.in.ia_ifa.if_ibytes;
402 			}
403 
404 			ifaddraddr = (u_long)TAILQ_NEXT(&ifaddr.ifa, ifa_link);
405 		}
406 
407 		show_stat("lu", 8, ipackets, link_layer|network_layer);
408 		show_stat("lu", 5, ierrors, link_layer);
409 		if (bflag)
410 			show_stat("lu", 10, ibytes, link_layer|network_layer);
411 
412 		show_stat("lu", 8, opackets, link_layer|network_layer);
413 		show_stat("lu", 5, oerrors, link_layer);
414 		if (bflag)
415 			show_stat("lu", 10, obytes, link_layer|network_layer);
416 
417 		show_stat("lu", 5, collisions, link_layer);
418 		if (tflag)
419 			show_stat("d", 4, timer, link_layer);
420 
421 		if (dflag)
422 			show_stat("d", 4, drops, link_layer);
423 
424 		putchar('\n');
425 		if (aflag && ifaddrfound) {
426 			/*
427 			 * Print family's multicast addresses
428 			 */
429 			struct ifmultiaddr *multiaddr;
430 			struct ifmultiaddr ifma;
431 			union {
432 				struct sockaddr sa;
433 				struct sockaddr_in in;
434 #ifdef INET6
435 				struct sockaddr_in6 in6;
436 #endif /* INET6 */
437 				struct sockaddr_dl dl;
438 			} msa;
439 			const char *fmt;
440 
441 			TAILQ_FOREACH(multiaddr, &ifnet.if_multiaddrs, ifma_link) {
442 				if (kread((u_long)multiaddr, (char *)&ifma,
443 					  sizeof ifma))
444 					break;
445 				multiaddr = &ifma;
446 				if (kread((u_long)ifma.ifma_addr, (char *)&msa,
447 					  sizeof msa))
448 					break;
449 				if (msa.sa.sa_family != sa->sa_family)
450 					continue;
451 
452 				fmt = 0;
453 				switch (msa.sa.sa_family) {
454 				case AF_INET:
455 					fmt = routename(msa.in.sin_addr.s_addr);
456 					break;
457 #ifdef INET6
458 				case AF_INET6:
459 					printf("%*s %-19.19s(refs: %d)\n",
460 					       Wflag ? 27 : 25, "",
461 					       inet_ntop(AF_INET6,
462 							 &msa.in6.sin6_addr,
463 							 ntop_buf,
464 							 sizeof(ntop_buf)),
465 					       ifma.ifma_refcount);
466 					break;
467 #endif /* INET6 */
468 				case AF_LINK:
469 					switch (msa.dl.sdl_type) {
470 					case IFT_ETHER:
471 					case IFT_FDDI:
472 						fmt = ether_ntoa(
473 							(struct ether_addr *)
474 							LLADDR(&msa.dl));
475 						break;
476 					}
477 					break;
478 				}
479 				if (fmt) {
480 					printf("%*s %-17.17s",
481 					    Wflag ? 27 : 25, "", fmt);
482 					if (msa.sa.sa_family == AF_LINK) {
483 						printf(" %8lu", imcasts);
484 						printf("%*s",
485 						    bflag ? 17 : 6, "");
486 						printf(" %8lu", omcasts);
487 					}
488 					putchar('\n');
489 				}
490 			}
491 		}
492 	}
493 }
494 
495 struct	iftot {
496 	SLIST_ENTRY(iftot) chain;
497 	char	ift_name[IFNAMSIZ];	/* interface name */
498 	u_long	ift_ip;			/* input packets */
499 	u_long	ift_ie;			/* input errors */
500 	u_long	ift_op;			/* output packets */
501 	u_long	ift_oe;			/* output errors */
502 	u_long	ift_co;			/* collisions */
503 	u_int	ift_dr;			/* drops */
504 	u_long	ift_ib;			/* input bytes */
505 	u_long	ift_ob;			/* output bytes */
506 };
507 
508 u_char	signalled;			/* set if alarm goes off "early" */
509 
510 /*
511  * Print a running summary of interface statistics.
512  * Repeat display every interval seconds, showing statistics
513  * collected over that interval.  Assumes that interval is non-zero.
514  * First line printed at top of screen is always cumulative.
515  * XXX - should be rewritten to use ifmib(4).
516  */
517 static void
518 sidewaysintpr(unsigned interval1, u_long off)
519 {
520 	struct ifnet ifnet;
521 	u_long firstifnet;
522 	struct ifnethead ifnethead;
523 	struct iftot *iftot, *ip, *ipn, *total, *sum, *interesting;
524 	int line;
525 	int oldmask, first;
526 	u_long interesting_off;
527 
528 	if (kread(off, (char *)&ifnethead, sizeof ifnethead))
529 		return;
530 	firstifnet = (u_long)TAILQ_FIRST(&ifnethead);
531 
532 	if ((iftot = malloc(sizeof(struct iftot))) == NULL) {
533 		printf("malloc failed\n");
534 		exit(1);
535 	}
536 	memset(iftot, 0, sizeof(struct iftot));
537 
538 	interesting = NULL;
539 	interesting_off = 0;
540 	for (off = firstifnet, ip = iftot; off;) {
541 		char name[IFNAMSIZ];
542 
543 		if (kread(off, (char *)&ifnet, sizeof ifnet))
544 			break;
545 		strlcpy(name, ifnet.if_xname, sizeof(name));
546 		if (interface && strcmp(name, interface) == 0) {
547 			interesting = ip;
548 			interesting_off = off;
549 		}
550 		snprintf(ip->ift_name, sizeof(ip->ift_name), "(%s)", name);;
551 		if ((ipn = malloc(sizeof(struct iftot))) == NULL) {
552 			printf("malloc failed\n");
553 			exit(1);
554 		}
555 		memset(ipn, 0, sizeof(struct iftot));
556 		SLIST_NEXT(ip, chain) = ipn;
557 		ip = ipn;
558 		off = (u_long)TAILQ_NEXT(&ifnet, if_link);
559 	}
560 	if (interface && interesting == NULL)
561 		errx(1, "%s: unknown interface", interface);
562 	if ((total = malloc(sizeof(struct iftot))) == NULL) {
563 		printf("malloc failed\n");
564 		exit(1);
565 	}
566 	memset(total, 0, sizeof(struct iftot));
567 	if ((sum = malloc(sizeof(struct iftot))) == NULL) {
568 		printf("malloc failed\n");
569 		exit(1);
570 	}
571 	memset(sum, 0, sizeof(struct iftot));
572 
573 	(void)signal(SIGALRM, catchalarm);
574 	signalled = NO;
575 	(void)alarm(interval1);
576 	first = 1;
577 banner:
578 	printf("%17s %14s %16s", "input",
579 	    interesting ? interesting->ift_name : "(Total)", "output");
580 	putchar('\n');
581 	printf("%10s %5s %10s %10s %5s %10s %5s",
582 	    "packets", "errs", "bytes", "packets", "errs", "bytes", "colls");
583 	if (dflag)
584 		printf(" %5.5s", "drops");
585 	putchar('\n');
586 	fflush(stdout);
587 	line = 0;
588 loop:
589 	if (interesting != NULL) {
590 		ip = interesting;
591 		if (kread(interesting_off, (char *)&ifnet, sizeof ifnet)) {
592 			printf("???\n");
593 			exit(1);
594 		};
595 		if (!first) {
596 			show_stat("lu", 10, ifnet.if_ipackets - ip->ift_ip, 1);
597 			show_stat("lu", 5, ifnet.if_ierrors - ip->ift_ie, 1);
598 			show_stat("lu", 10, ifnet.if_ibytes - ip->ift_ib, 1);
599 			show_stat("lu", 10, ifnet.if_opackets - ip->ift_op, 1);
600 			show_stat("lu", 5, ifnet.if_oerrors - ip->ift_oe, 1);
601 			show_stat("lu", 10, ifnet.if_obytes - ip->ift_ob, 1);
602 			show_stat("lu", 5, ifnet.if_collisions - ip->ift_co, 1);
603 			if (dflag)
604 				show_stat("u", 5,
605 				    ifnet.if_snd.ifq_drops - ip->ift_dr, 1);
606 		}
607 		ip->ift_ip = ifnet.if_ipackets;
608 		ip->ift_ie = ifnet.if_ierrors;
609 		ip->ift_ib = ifnet.if_ibytes;
610 		ip->ift_op = ifnet.if_opackets;
611 		ip->ift_oe = ifnet.if_oerrors;
612 		ip->ift_ob = ifnet.if_obytes;
613 		ip->ift_co = ifnet.if_collisions;
614 		ip->ift_dr = ifnet.if_snd.ifq_drops;
615 	} else {
616 		sum->ift_ip = 0;
617 		sum->ift_ie = 0;
618 		sum->ift_ib = 0;
619 		sum->ift_op = 0;
620 		sum->ift_oe = 0;
621 		sum->ift_ob = 0;
622 		sum->ift_co = 0;
623 		sum->ift_dr = 0;
624 		for (off = firstifnet, ip = iftot;
625 		     off && SLIST_NEXT(ip, chain) != NULL;
626 		     ip = SLIST_NEXT(ip, chain)) {
627 			if (kread(off, (char *)&ifnet, sizeof ifnet)) {
628 				off = 0;
629 				continue;
630 			}
631 			sum->ift_ip += ifnet.if_ipackets;
632 			sum->ift_ie += ifnet.if_ierrors;
633 			sum->ift_ib += ifnet.if_ibytes;
634 			sum->ift_op += ifnet.if_opackets;
635 			sum->ift_oe += ifnet.if_oerrors;
636 			sum->ift_ob += ifnet.if_obytes;
637 			sum->ift_co += ifnet.if_collisions;
638 			sum->ift_dr += ifnet.if_snd.ifq_drops;
639 			off = (u_long)TAILQ_NEXT(&ifnet, if_link);
640 		}
641 		if (!first) {
642 			show_stat("lu", 10, sum->ift_ip - total->ift_ip, 1);
643 			show_stat("lu", 5, sum->ift_ie - total->ift_ie, 1);
644 			show_stat("lu", 10, sum->ift_ib - total->ift_ib, 1);
645 			show_stat("lu", 10, sum->ift_op - total->ift_op, 1);
646 			show_stat("lu", 5, sum->ift_oe - total->ift_oe, 1);
647 			show_stat("lu", 10, sum->ift_ob - total->ift_ob, 1);
648 			show_stat("lu", 5, sum->ift_co - total->ift_co, 1);
649 			if (dflag)
650 				show_stat("u", 5,
651 				    sum->ift_dr - total->ift_dr, 1);
652 		}
653 		*total = *sum;
654 	}
655 	if (!first)
656 		putchar('\n');
657 	fflush(stdout);
658 	oldmask = sigblock(sigmask(SIGALRM));
659 	if (! signalled) {
660 		sigpause(0);
661 	}
662 	sigsetmask(oldmask);
663 	signalled = NO;
664 	(void)alarm(interval1);
665 	line++;
666 	first = 0;
667 	if (line == 21)
668 		goto banner;
669 	else
670 		goto loop;
671 	/*NOTREACHED*/
672 }
673 
674 /*
675  * Called if an interval expires before sidewaysintpr has completed a loop.
676  * Sets a flag to not wait for the alarm.
677  */
678 static void
679 catchalarm(int signo __unused)
680 {
681 	signalled = YES;
682 }
683