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 #ifndef lint
  35 /*
  36 static char sccsid[] = "@(#)if.c        8.3 (Berkeley) 4/28/95";
  37 */
  38 static const char rcsid[] =
  39   "$FreeBSD: src/usr.bin/netstat/if.c,v 1.32.2.9 2001/09/17 14:35:46 ru Exp $";
  40 #endif /* not lint */
  41
  42 #include <sys/types.h>
  43 #include <sys/protosw.h>
  44 #include <sys/socket.h>
  45 #include <sys/sysctl.h>
  46 #include <sys/time.h>
  47
  48 #include <net/if.h>
  49 #include <net/if_var.h>
  50 #include <net/if_dl.h>
  51 #include <net/if_types.h>
  52 #include <net/bridge.h>
  53 #include <net/ethernet.h>
  54 #include <netinet/in.h>
  55 #include <netinet/in_var.h>
  56 #include <netipx/ipx.h>
  57 #include <netipx/ipx_if.h>
  58 #ifdef NS
  59 #include <netns/ns.h>
  60 #include <netns/ns_if.h>
  61 #endif
  62 #ifdef ISO
  63 #include <netiso/iso.h>
  64 #include <netiso/iso_var.h>
  65 #endif
  66 #include <arpa/inet.h>
  67
  68 #include <signal.h>
  69 #include <stdio.h>
  70 #include <stdlib.h>
  71 #include <string.h>
  72 #include <unistd.h>
  73
  74 #include "netstat.h"
  75
  76 #define YES     1
  77 #define NO      0
  78
  79 static void sidewaysintpr (u_int, u_long);
  80 static void catchalarm (int);
  81
  82 #ifdef INET6
  83 char *netname6 (struct sockaddr_in6 *, struct in6_addr *);
  84 static char ntop_buf[INET6_ADDRSTRLEN];         /* for inet_ntop() */
  85 static int bdg_done;
  86 #endif
  87
  88 /* print bridge statistics */
  89 void
  90 bdg_stats(u_long dummy __unused, char *name, int af __unused)
  91 {
  92     int i;
  93     size_t slen ;
  94     struct bdg_stats s ;
  95     int mib[4] ;
  96
  97     slen = sizeof(s);
  98
  99     mib[0] = CTL_NET ;
 100     mib[1] = PF_LINK ;
 101     mib[2] = IFT_ETHER ;
 102     mib[3] = PF_BDG ;
 103     if (sysctl(mib,4, &s,&slen,NULL,0)==-1)
 104         return ; /* no bridging */
 105 #ifdef INET6
 106     if (bdg_done != 0)
 107         return;
 108     else
 109         bdg_done = 1;
 110 #endif
 111     printf("-- Bridging statistics (%s) --\n", name) ;
 112     printf(
 113 "Name          In      Out  Forward     Drop    Bcast    Mcast    Local  Unknown\n");
 114     for (i = 0 ; i < 16 ; i++) {
 115         if (s.s[i].name[0])
 116         printf("%-6s %9ld%9ld%9ld%9ld%9ld%9ld%9ld%9ld\n",
 117           s.s[i].name,
 118           s.s[i].p_in[(int)BDG_IN],
 119           s.s[i].p_in[(int)BDG_OUT],
 120           s.s[i].p_in[(int)BDG_FORWARD],
 121           s.s[i].p_in[(int)BDG_DROP],
 122           s.s[i].p_in[(int)BDG_BCAST],
 123           s.s[i].p_in[(int)BDG_MCAST],
 124           s.s[i].p_in[(int)BDG_LOCAL],
 125           s.s[i].p_in[(int)BDG_UNKNOWN] );
 126     }
 127 }
 128
 129
 130
 131
 132 /*
 133  * Display a formatted value, or a '-' in the same space.
 134  */
 135 static void
 136 show_stat(const char *fmt, int width, u_long value, short showvalue)
 137 {
 138         char newfmt[32];
 139
 140         /* Construct the format string */
 141         if (showvalue) {
 142                 sprintf(newfmt, "%%%d%s", width, fmt);
 143                 printf(newfmt, value);
 144         } else {
 145                 sprintf(newfmt, "%%%ds", width);
 146                 printf(newfmt, "-");
 147         }
 148 }
 149
 150
 151
 152 /*
 153  * Print a description of the network interfaces.
 154  */
 155 void
 156 intpr(int interval, u_long ifnetaddr, void (*pfunc)(char *))
 157 {
 158         struct ifnet ifnet;
 159         struct ifnethead ifnethead;
 160         union {
 161                 struct ifaddr ifa;
 162                 struct in_ifaddr in;
 163 #ifdef INET6
 164                 struct in6_ifaddr in6;
 165 #endif
 166                 struct ipx_ifaddr ipx;
 167 #ifdef NS
 168                 struct ns_ifaddr ns;
 169 #endif
 170 #ifdef ISO
 171                 struct iso_ifaddr iso;
 172 #endif
 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 oerrors;
 182         u_long ierrors;
 183         u_long collisions;
 184         short timer;
 185         int drops;
 186         struct sockaddr *sa = NULL;
 187         char name[32], tname[16];
 188         short network_layer;
 189         short link_layer;
 190
 191         if (ifnetaddr == 0) {
 192                 printf("ifnet: symbol not defined\n");
 193                 return;
 194         }
 195         if (interval) {
 196                 sidewaysintpr((unsigned)interval, ifnetaddr);
 197                 return;
 198         }
 199         if (kread(ifnetaddr, (char *)&ifnethead, sizeof ifnethead))
 200                 return;
 201         ifnetaddr = (u_long)TAILQ_FIRST(&ifnethead);
 202         if (kread(ifnetaddr, (char *)&ifnet, sizeof ifnet))
 203                 return;
 204
 205         if (!pfunc) {
 206                 printf("%-5.5s %-5.5s %-13.13s %-15.15s %8.8s %5.5s",
 207                        "Name", "Mtu", "Network", "Address", "Ipkts", "Ierrs");
 208                 if (bflag)
 209                         printf(" %10.10s","Ibytes");
 210                 printf(" %8.8s %5.5s", "Opkts", "Oerrs");
 211                 if (bflag)
 212                         printf(" %10.10s","Obytes");
 213                 printf(" %5s", "Coll");
 214                 if (tflag)
 215                         printf(" %s", "Time");
 216                 if (dflag)
 217                         printf(" %s", "Drop");
 218                 putchar('\n');
 219         }
 220         ifaddraddr = 0;
 221         while (ifnetaddr || ifaddraddr) {
 222                 struct sockaddr_in *sin;
 223 #ifdef INET6
 224                 struct sockaddr_in6 *sin6;
 225 #endif
 226                 register char *cp;
 227                 int n, m;
 228
 229                 network_layer = 0;
 230                 link_layer = 0;
 231
 232                 if (ifaddraddr == 0) {
 233                         ifnetfound = ifnetaddr;
 234                         if (kread(ifnetaddr, (char *)&ifnet, sizeof ifnet) ||
 235                             kread((u_long)ifnet.if_name, tname, 16))
 236                                 return;
 237                         tname[15] = '\0';
 238                         ifnetaddr = (u_long)TAILQ_NEXT(&ifnet, if_link);
 239                         snprintf(name, 32, "%s%d", tname, ifnet.if_unit);
 240                         if (interface != 0 && (strcmp(name, interface) != 0))
 241                                 continue;
 242                         cp = index(name, '\0');
 243
 244                         if (pfunc) {
 245                                 (*pfunc)(name);
 246                                 continue;
 247                         }
 248
 249                         if ((ifnet.if_flags&IFF_UP) == 0)
 250                                 *cp++ = '*';
 251                         *cp = '\0';
 252                         ifaddraddr = (u_long)TAILQ_FIRST(&ifnet.if_addrhead);
 253                 }
 254                 ifaddrfound = ifaddraddr;
 255
 256                 /*
 257                  * Get the interface stats.  These may get
 258                  * overriden below on a per-interface basis.
 259                  */
 260                 opackets = ifnet.if_opackets;
 261                 ipackets = ifnet.if_ipackets;
 262                 obytes = ifnet.if_obytes;
 263                 ibytes = ifnet.if_ibytes;
 264                 oerrors = ifnet.if_oerrors;
 265                 ierrors = ifnet.if_ierrors;
 266                 collisions = ifnet.if_collisions;
 267                 timer = ifnet.if_timer;
 268                 drops = ifnet.if_snd.ifq_drops;
 269
 270                 if (ifaddraddr == 0) {
 271                         printf("%-5.5s %-5lu ", name, ifnet.if_mtu);
 272                         printf("%-13.13s ", "none");
 273                         printf("%-15.15s ", "none");
 274                 } else {
 275                         if (kread(ifaddraddr, (char *)&ifaddr, sizeof ifaddr)) {
 276                                 ifaddraddr = 0;
 277                                 continue;
 278                         }
 279 #define CP(x) ((char *)(x))
 280                         cp = (CP(ifaddr.ifa.ifa_addr) - CP(ifaddraddr)) +
 281                                 CP(&ifaddr);
 282                         sa = (struct sockaddr *)cp;
 283                         if (af != AF_UNSPEC && sa->sa_family != af) {
 284                                 ifaddraddr =
 285                                     (u_long)TAILQ_NEXT(&ifaddr.ifa, ifa_link);
 286                                 continue;
 287                         }
 288                         printf("%-5.5s %-5lu ", name, ifnet.if_mtu);
 289                         switch (sa->sa_family) {
 290                         case AF_UNSPEC:
 291                                 printf("%-13.13s ", "none");
 292                                 printf("%-15.15s ", "none");
 293                                 break;
 294                         case AF_INET:
 295                                 sin = (struct sockaddr_in *)sa;
 296 #ifdef notdef
 297                                 /* can't use inet_makeaddr because kernel
 298                                  * keeps nets unshifted.
 299                                  */
 300                                 in = inet_makeaddr(ifaddr.in.ia_subnet,
 301                                         INADDR_ANY);
 302                                 printf("%-13.13s ", netname(in.s_addr,
 303                                     ifaddr.in.ia_subnetmask));
 304 #else
 305                                 printf("%-13.13s ",
 306                                     netname(htonl(ifaddr.in.ia_subnet),
 307                                     ifaddr.in.ia_subnetmask));
 308 #endif
 309                                 printf("%-15.15s ",
 310                                     routename(sin->sin_addr.s_addr));
 311
 312                                 network_layer = 1;
 313                                 break;
 314 #ifdef INET6
 315                         case AF_INET6:
 316                                 sin6 = (struct sockaddr_in6 *)sa;
 317                                 printf("%-11.11s ",
 318                                        netname6(&ifaddr.in6.ia_addr,
 319                                                 &ifaddr.in6.ia_prefixmask.sin6_addr));
 320                                 printf("%-17.17s ",
 321                                     (char *)inet_ntop(AF_INET6,
 322                                         &sin6->sin6_addr,
 323                                         ntop_buf, sizeof(ntop_buf)));
 324
 325                                 network_layer = 1;
 326                                 break;
 327 #endif /*INET6*/
 328                         case AF_IPX:
 329                                 {
 330                                 struct sockaddr_ipx *sipx =
 331                                         (struct sockaddr_ipx *)sa;
 332                                 u_long net;
 333                                 char netnum[10];
 334
 335                                 *(union ipx_net *) &net = sipx->sipx_addr.x_net;
 336                                 sprintf(netnum, "%lx", (u_long)ntohl(net));
 337                                 printf("ipx:%-8s  ", netnum);
 338 /*                              printf("ipx:%-8s ", netname(net, 0L)); */
 339                                 printf("%-15s ",
 340                                     ipx_phost((struct sockaddr *)sipx));
 341                                 }
 342                                 break;
 343
 344                         case AF_APPLETALK:
 345                                 printf("atalk:%-12.12s ",atalk_print(sa,0x10) );
 346                                 printf("%-9.9s  ",atalk_print(sa,0x0b) );
 347                                 break;
 348 #ifdef NS
 349                         case AF_NS:
 350                                 {
 351                                 struct sockaddr_ns *sns =
 352                                         (struct sockaddr_ns *)sa;
 353                                 u_long net;
 354                                 char netnum[10];
 355
 356                                 *(union ns_net *) &net = sns->sns_addr.x_net;
 357                                 sprintf(netnum, "%lxH", ntohl(net));
 358                                 upHex(netnum);
 359                                 printf("ns:%-8s ", netnum);
 360                                 printf("%-15s ",
 361                                     ns_phost((struct sockaddr *)sns));
 362                                 }
 363                                 break;
 364 #endif
 365                         case AF_LINK:
 366                                 {
 367                                 struct sockaddr_dl *sdl =
 368                                         (struct sockaddr_dl *)sa;
 369                                 char linknum[10];
 370                                 cp = (char *)LLADDR(sdl);
 371                                 n = sdl->sdl_alen;
 372                                 sprintf(linknum, "<Link#%d>", sdl->sdl_index);
 373                                 m = printf("%-11.11s ", linknum);
 374                                 }
 375                                 goto hexprint;
 376                         default:
 377                                 m = printf("(%d)", sa->sa_family);
 378                                 for (cp = sa->sa_len + (char *)sa;
 379                                         --cp > sa->sa_data && (*cp == 0);) {}
 380                                 n = cp - sa->sa_data + 1;
 381                                 cp = sa->sa_data;
 382                         hexprint:
 383                                 while (--n >= 0)
 384                                         m += printf("%02x%c", *cp++ & 0xff,
 385                                                     n > 0 ? ':' : ' ');
 386                                 m = 30 - m;
 387                                 while (m-- > 0)
 388                                         putchar(' ');
 389
 390                                 link_layer = 1;
 391                                 break;
 392                         }
 393
 394                         /*
 395                          * Fixup the statistics for interfaces that
 396                          * update stats for their network addresses
 397                          */
 398                         if (network_layer) {
 399                                 opackets = ifaddr.in.ia_ifa.if_opackets;
 400                                 ipackets = ifaddr.in.ia_ifa.if_ipackets;
 401                                 obytes = ifaddr.in.ia_ifa.if_obytes;
 402                                 ibytes = ifaddr.in.ia_ifa.if_ibytes;
 403                         }
 404
 405                         ifaddraddr = (u_long)TAILQ_NEXT(&ifaddr.ifa, ifa_link);
 406                 }
 407
 408                 show_stat("lu", 8, ipackets, link_layer|network_layer);
 409                 printf(" ");
 410                 show_stat("lu", 5, ierrors, link_layer);
 411                 printf(" ");
 412                 if (bflag) {
 413                         show_stat("lu", 10, ibytes, link_layer|network_layer);
 414                         printf(" ");
 415                 }
 416                 show_stat("lu", 8, opackets, link_layer|network_layer);
 417                 printf(" ");
 418                 show_stat("lu", 5, oerrors, link_layer);
 419                 printf(" ");
 420                 if (bflag) {
 421                         show_stat("lu", 10, obytes, link_layer|network_layer);
 422                         printf(" ");
 423                 }
 424                 show_stat("lu", 5, collisions, link_layer);
 425                 if (tflag) {
 426                         printf(" ");
 427                         show_stat("d", 3, timer, link_layer);
 428                 }
 429                 if (dflag) {
 430                         printf(" ");
 431                         show_stat("d", 3, drops, link_layer);
 432                 }
 433                 putchar('\n');
 434                 if (aflag && ifaddrfound) {
 435                         /*
 436                          * Print family's multicast addresses
 437                          */
 438                         u_long multiaddr;
 439                         struct ifmultiaddr ifma;
 440                         union {
 441                                 struct sockaddr sa;
 442                                 struct sockaddr_in in;
 443 #ifdef INET6
 444                                 struct sockaddr_in6 in6;
 445 #endif /* INET6 */
 446                                 struct sockaddr_dl dl;
 447                         } msa;
 448                         const char *fmt;
 449
 450                         for(multiaddr = (u_long)ifnet.if_multiaddrs.lh_first;
 451                             multiaddr;
 452                             multiaddr = (u_long)ifma.ifma_link.le_next) {
 453                                 if (kread(multiaddr, (char *)&ifma,
 454                                           sizeof ifma))
 455                                         break;
 456                                 if (kread((u_long)ifma.ifma_addr, (char *)&msa,
 457                                           sizeof msa))
 458                                         break;
 459                                 if (msa.sa.sa_family != sa->sa_family)
 460                                         continue;
 461
 462                                 fmt = 0;
 463                                 switch (msa.sa.sa_family) {
 464                                 case AF_INET:
 465                                         fmt = routename(msa.in.sin_addr.s_addr);
 466                                         break;
 467 #ifdef INET6
 468                                 case AF_INET6:
 469                                         printf("%23s %-19.19s(refs: %d)\n", "",
 470                                                inet_ntop(AF_INET6,
 471                                                          &msa.in6.sin6_addr,
 472                                                          ntop_buf,
 473                                                          sizeof(ntop_buf)),
 474                                                ifma.ifma_refcount);
 475                                         break;
 476 #endif /* INET6 */
 477                                 case AF_LINK:
 478                                         switch (msa.dl.sdl_type) {
 479                                         case IFT_ETHER:
 480                                         case IFT_FDDI:
 481                                                 fmt = ether_ntoa(
 482                                                         (struct ether_addr *)
 483                                                         LLADDR(&msa.dl));
 484                                                 break;
 485                                         }
 486                                         break;
 487                                 }
 488                                 if (fmt)
 489                                         printf("%23s %s\n", "", fmt);
 490                         }
 491                 }
 492         }
 493 }
 494
 495 struct  iftot {
 496         SLIST_ENTRY(iftot) chain;
 497         char    ift_name[16];           /* 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 interval, 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         register 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[16], tname[16];
 542
 543                 if (kread(off, (char *)&ifnet, sizeof ifnet))
 544                         break;
 545                 if (kread((u_long)ifnet.if_name, tname, 16))
 546                         break;
 547                 tname[15] = '\0';
 548                 snprintf(name, 16, "%s%d", tname, ifnet.if_unit);
 549                 if (interface && strcmp(name, interface) == 0) {
 550                         interesting = ip;
 551                         interesting_off = off;
 552                 }
 553                 snprintf(ip->ift_name, 16, "(%s)", name);;
 554                 if ((ipn = malloc(sizeof(struct iftot))) == NULL) {
 555                         printf("malloc failed\n");
 556                         exit(1);
 557                 }
 558                 memset(ipn, 0, sizeof(struct iftot));
 559                 SLIST_NEXT(ip, chain) = ipn;
 560                 ip = ipn;
 561                 off = (u_long)TAILQ_NEXT(&ifnet, if_link);
 562         }
 563         if ((total = malloc(sizeof(struct iftot))) == NULL) {
 564                 printf("malloc failed\n");
 565                 exit(1);
 566         }
 567         memset(total, 0, sizeof(struct iftot));
 568         if ((sum = malloc(sizeof(struct iftot))) == NULL) {
 569                 printf("malloc failed\n");
 570                 exit(1);
 571         }
 572         memset(sum, 0, sizeof(struct iftot));
 573
 574
 575         (void)signal(SIGALRM, catchalarm);
 576         signalled = NO;
 577         (void)alarm(interval);
 578         first = 1;
 579 banner:
 580         printf("%17s %14s %16s", "input",
 581             interesting ? interesting->ift_name : "(Total)", "output");
 582         putchar('\n');
 583         printf("%10s %5s %10s %10s %5s %10s %5s",
 584             "packets", "errs", "bytes", "packets", "errs", "bytes", "colls");
 585         if (dflag)
 586                 printf(" %5.5s", "drops");
 587         putchar('\n');
 588         fflush(stdout);
 589         line = 0;
 590 loop:
 591         if (interesting != NULL) {
 592                 ip = interesting;
 593                 if (kread(interesting_off, (char *)&ifnet, sizeof ifnet)) {
 594                         printf("???\n");
 595                         exit(1);
 596                 };
 597                 if (!first) {
 598                         printf("%10lu %5lu %10lu %10lu %5lu %10lu %5lu",
 599                                 ifnet.if_ipackets - ip->ift_ip,
 600                                 ifnet.if_ierrors - ip->ift_ie,
 601                                 ifnet.if_ibytes - ip->ift_ib,
 602                                 ifnet.if_opackets - ip->ift_op,
 603                                 ifnet.if_oerrors - ip->ift_oe,
 604                                 ifnet.if_obytes - ip->ift_ob,
 605                                 ifnet.if_collisions - ip->ift_co);
 606                         if (dflag)
 607                                 printf(" %5u", ifnet.if_snd.ifq_drops - ip->ift_dr);
 608                 }
 609                 ip->ift_ip = ifnet.if_ipackets;
 610                 ip->ift_ie = ifnet.if_ierrors;
 611                 ip->ift_ib = ifnet.if_ibytes;
 612                 ip->ift_op = ifnet.if_opackets;
 613                 ip->ift_oe = ifnet.if_oerrors;
 614                 ip->ift_ob = ifnet.if_obytes;
 615                 ip->ift_co = ifnet.if_collisions;
 616                 ip->ift_dr = ifnet.if_snd.ifq_drops;
 617         } else {
 618                 sum->ift_ip = 0;
 619                 sum->ift_ie = 0;
 620                 sum->ift_ib = 0;
 621                 sum->ift_op = 0;
 622                 sum->ift_oe = 0;
 623                 sum->ift_ob = 0;
 624                 sum->ift_co = 0;
 625                 sum->ift_dr = 0;
 626                 for (off = firstifnet, ip = iftot;
 627                      off && SLIST_NEXT(ip, chain) != NULL;
 628                      ip = SLIST_NEXT(ip, chain)) {
 629                         if (kread(off, (char *)&ifnet, sizeof ifnet)) {
 630                                 off = 0;
 631                                 continue;
 632                         }
 633                         sum->ift_ip += ifnet.if_ipackets;
 634                         sum->ift_ie += ifnet.if_ierrors;
 635                         sum->ift_ib += ifnet.if_ibytes;
 636                         sum->ift_op += ifnet.if_opackets;
 637                         sum->ift_oe += ifnet.if_oerrors;
 638                         sum->ift_ob += ifnet.if_obytes;
 639                         sum->ift_co += ifnet.if_collisions;
 640                         sum->ift_dr += ifnet.if_snd.ifq_drops;
 641                         off = (u_long)TAILQ_NEXT(&ifnet, if_link);
 642                 }
 643                 if (!first) {
 644                         printf("%10lu %5lu %10lu %10lu %5lu %10lu %5lu",
 645                                 sum->ift_ip - total->ift_ip,
 646                                 sum->ift_ie - total->ift_ie,
 647                                 sum->ift_ib - total->ift_ib,
 648                                 sum->ift_op - total->ift_op,
 649                                 sum->ift_oe - total->ift_oe,
 650                                 sum->ift_ob - total->ift_ob,
 651                                 sum->ift_co - total->ift_co);
 652                         if (dflag)
 653                                 printf(" %5u", sum->ift_dr - total->ift_dr);
 654                 }
 655                 *total = *sum;
 656         }
 657         if (!first)
 658                 putchar('\n');
 659         fflush(stdout);
 660         oldmask = sigblock(sigmask(SIGALRM));
 661         if (! signalled) {
 662                 sigpause(0);
 663         }
 664         sigsetmask(oldmask);
 665         signalled = NO;
 666         (void)alarm(interval);
 667         line++;
 668         first = 0;
 669         if (line == 21)
 670                 goto banner;
 671         else
 672                 goto loop;
 673         /*NOTREACHED*/
 674 }
 675
 676 /*
 677  * Called if an interval expires before sidewaysintpr has completed a loop.
 678  * Sets a flag to not wait for the alarm.
 679  */
 680 static void
 681 catchalarm(int signo __unused)
 682 {
 683         signalled = YES;
 684 }