usr.bin/netstat/if.c

   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 }