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  * @(#)if.c     8.3 (Berkeley) 4/28/95
  34  * $FreeBSD: src/usr.bin/netstat/if.c,v 1.32.2.9 2001/09/17 14:35:46 ru Exp $
  35  * $DragonFly: src/usr.bin/netstat/if.c,v 1.6 2004/08/19 23:35:45 joerg Exp $
  36  */
  37
  38 #include <sys/param.h>
  39 #include <sys/protosw.h>
  40 #include <sys/socket.h>
  41 #include <sys/sysctl.h>
  42 #include <sys/time.h>
  43
  44 #include <net/if.h>
  45 #include <net/if_var.h>
  46 #include <net/if_dl.h>
  47 #include <net/if_types.h>
  48 #include <net/bridge/bridge.h>
  49 #include <net/ethernet.h>
  50 #include <netinet/in.h>
  51 #include <netinet/in_var.h>
  52 #include <netproto/ipx/ipx.h>
  53 #include <netproto/ipx/ipx_if.h>
  54 #ifdef NS
  55 #include <netproto/ns/ns.h>
  56 #include <netproto/ns/ns_if.h>
  57 #endif
  58 #ifdef ISO
  59 #include <netiso/iso.h>
  60 #include <netiso/iso_var.h>
  61 #endif
  62 #include <arpa/inet.h>
  63
  64 #include <signal.h>
  65 #include <stdio.h>
  66 #include <stdlib.h>
  67 #include <string.h>
  68 #include <unistd.h>
  69
  70 #include "netstat.h"
  71
  72 #define YES     1
  73 #define NO      0
  74
  75 static void sidewaysintpr (u_int, u_long);
  76 static void catchalarm (int);
  77
  78 #ifdef INET6
  79 char *netname6 (struct sockaddr_in6 *, struct in6_addr *);
  80 static char ntop_buf[INET6_ADDRSTRLEN];         /* for inet_ntop() */
  81 static int bdg_done;
  82 #endif
  83
  84 /* print bridge statistics */
  85 void
  86 bdg_stats(u_long dummy __unused, char *name, int af __unused)
  87 {
  88     int i;
  89     size_t slen ;
  90     struct bdg_stats s ;
  91     int mib[4] ;
  92
  93     slen = sizeof(s);
  94
  95     mib[0] = CTL_NET ;
  96     mib[1] = PF_LINK ;
  97     mib[2] = IFT_ETHER ;
  98     mib[3] = PF_BDG ;
  99     if (sysctl(mib,4, &s,&slen,NULL,0)==-1)
 100         return ; /* no bridging */
 101 #ifdef INET6
 102     if (bdg_done != 0)
 103         return;
 104     else
 105         bdg_done = 1;
 106 #endif
 107     printf("-- Bridging statistics (%s) --\n", name) ;
 108     printf(
 109 "Name          In      Out  Forward     Drop    Bcast    Mcast    Local  Unknown\n");
 110     for (i = 0 ; i < 16 ; i++) {
 111         if (s.s[i].name[0])
 112         printf("%-6s %9ld%9ld%9ld%9ld%9ld%9ld%9ld%9ld\n",
 113           s.s[i].name,
 114           s.s[i].p_in[(int)BDG_IN],
 115           s.s[i].p_in[(int)BDG_OUT],
 116           s.s[i].p_in[(int)BDG_FORWARD],
 117           s.s[i].p_in[(int)BDG_DROP],
 118           s.s[i].p_in[(int)BDG_BCAST],
 119           s.s[i].p_in[(int)BDG_MCAST],
 120           s.s[i].p_in[(int)BDG_LOCAL],
 121           s.s[i].p_in[(int)BDG_UNKNOWN] );
 122     }
 123 }
 124
 125
 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         /* Construct the format string */
 137         if (showvalue) {
 138                 sprintf(newfmt, "%%%d%s", width, fmt);
 139                 printf(newfmt, value);
 140         } else {
 141                 sprintf(newfmt, "%%%ds", width);
 142                 printf(newfmt, "-");
 143         }
 144 }
 145
 146
 147
 148 /*
 149  * Print a description of the network interfaces.
 150  */
 151 void
 152 intpr(int interval, u_long ifnetaddr, void (*pfunc)(char *))
 153 {
 154         struct ifnet ifnet;
 155         struct ifnethead ifnethead;
 156         union {
 157                 struct ifaddr ifa;
 158                 struct in_ifaddr in;
 159 #ifdef INET6
 160                 struct in6_ifaddr in6;
 161 #endif
 162                 struct ipx_ifaddr ipx;
 163 #ifdef NS
 164                 struct ns_ifaddr ns;
 165 #endif
 166 #ifdef ISO
 167                 struct iso_ifaddr iso;
 168 #endif
 169         } ifaddr;
 170         u_long ifaddraddr;
 171         u_long ifaddrfound;
 172         u_long ifnetfound;
 173         u_long opackets;
 174         u_long ipackets;
 175         u_long obytes;
 176         u_long ibytes;
 177         u_long oerrors;
 178         u_long ierrors;
 179         u_long collisions;
 180         short timer;
 181         int drops;
 182         struct sockaddr *sa = NULL;
 183         char name[IFNAMSIZ];
 184         short network_layer;
 185         short link_layer;
 186
 187         if (ifnetaddr == 0) {
 188                 printf("ifnet: symbol not defined\n");
 189                 return;
 190         }
 191         if (interval) {
 192                 sidewaysintpr((unsigned)interval, ifnetaddr);
 193                 return;
 194         }
 195         if (kread(ifnetaddr, (char *)&ifnethead, sizeof ifnethead))
 196                 return;
 197         ifnetaddr = (u_long)TAILQ_FIRST(&ifnethead);
 198         if (kread(ifnetaddr, (char *)&ifnet, sizeof ifnet))
 199                 return;
 200
 201         if (!pfunc) {
 202                 printf("%-7.7s %-5.5s %-13.13s %-15.15s %8.8s %5.5s",
 203                        "Name", "Mtu", "Network", "Address", "Ipkts", "Ierrs");
 204                 if (bflag)
 205                         printf(" %10.10s","Ibytes");
 206                 printf(" %8.8s %5.5s", "Opkts", "Oerrs");
 207                 if (bflag)
 208                         printf(" %10.10s","Obytes");
 209                 printf(" %5s", "Coll");
 210                 if (tflag)
 211                         printf(" %s", "Time");
 212                 if (dflag)
 213                         printf(" %s", "Drop");
 214                 putchar('\n');
 215         }
 216         ifaddraddr = 0;
 217         while (ifnetaddr || ifaddraddr) {
 218                 struct sockaddr_in *sin;
 219 #ifdef INET6
 220                 struct sockaddr_in6 *sin6;
 221 #endif
 222                 register char *cp;
 223                 int n, m;
 224
 225                 network_layer = 0;
 226                 link_layer = 0;
 227
 228                 if (ifaddraddr == 0) {
 229                         ifnetfound = ifnetaddr;
 230                         if (kread(ifnetaddr, (char *)&ifnet, sizeof ifnet))
 231                                 return;
 232                         strlcpy(name, ifnet.if_xname, sizeof(name));
 233                         ifnetaddr = (u_long)TAILQ_NEXT(&ifnet, if_link);
 234                         if (interface != 0 && (strcmp(name, interface) != 0))
 235                                 continue;
 236                         cp = index(name, '\0');
 237
 238                         if (pfunc) {
 239                                 (*pfunc)(name);
 240                                 continue;
 241                         }
 242
 243                         if ((ifnet.if_flags&IFF_UP) == 0)
 244                                 *cp++ = '*';
 245                         *cp = '\0';
 246                         ifaddraddr = (u_long)TAILQ_FIRST(&ifnet.if_addrhead);
 247                 }
 248                 ifaddrfound = ifaddraddr;
 249
 250                 /*
 251                  * Get the interface stats.  These may get
 252                  * overriden below on a per-interface basis.
 253                  */
 254                 opackets = ifnet.if_opackets;
 255                 ipackets = ifnet.if_ipackets;
 256                 obytes = ifnet.if_obytes;
 257                 ibytes = ifnet.if_ibytes;
 258                 oerrors = ifnet.if_oerrors;
 259                 ierrors = ifnet.if_ierrors;
 260                 collisions = ifnet.if_collisions;
 261                 timer = ifnet.if_timer;
 262                 drops = ifnet.if_snd.ifq_drops;
 263
 264                 if (ifaddraddr == 0) {
 265                         printf("%-7.7s %-5lu ", name, ifnet.if_mtu);
 266                         printf("%-13.13s ", "none");
 267                         printf("%-15.15s ", "none");
 268                 } else {
 269                         if (kread(ifaddraddr, (char *)&ifaddr, sizeof ifaddr)) {
 270                                 ifaddraddr = 0;
 271                                 continue;
 272                         }
 273 #define CP(x) ((char *)(x))
 274                         cp = (CP(ifaddr.ifa.ifa_addr) - CP(ifaddraddr)) +
 275                                 CP(&ifaddr);
 276                         sa = (struct sockaddr *)cp;
 277                         if (af != AF_UNSPEC && sa->sa_family != af) {
 278                                 ifaddraddr =
 279                                     (u_long)TAILQ_NEXT(&ifaddr.ifa, ifa_link);
 280                                 continue;
 281                         }
 282                         printf("%-7.7s %-5lu ", name, ifnet.if_mtu);
 283                         switch (sa->sa_family) {
 284                         case AF_UNSPEC:
 285                                 printf("%-13.13s ", "none");
 286                                 printf("%-15.15s ", "none");
 287                                 break;
 288                         case AF_INET:
 289                                 sin = (struct sockaddr_in *)sa;
 290 #ifdef notdef
 291                                 /* can't use inet_makeaddr because kernel
 292                                  * keeps nets unshifted.
 293                                  */
 294                                 in = inet_makeaddr(ifaddr.in.ia_subnet,
 295                                         INADDR_ANY);
 296                                 printf("%-13.13s ", netname(in.s_addr,
 297                                     ifaddr.in.ia_subnetmask));
 298 #else
 299                                 printf("%-13.13s ",
 300                                     netname(htonl(ifaddr.in.ia_subnet),
 301                                     ifaddr.in.ia_subnetmask));
 302 #endif
 303                                 printf("%-15.15s ",
 304                                     routename(sin->sin_addr.s_addr));
 305
 306                                 network_layer = 1;
 307                                 break;
 308 #ifdef INET6
 309                         case AF_INET6:
 310                                 sin6 = (struct sockaddr_in6 *)sa;
 311                                 printf("%-11.11s ",
 312                                        netname6(&ifaddr.in6.ia_addr,
 313                                                 &ifaddr.in6.ia_prefixmask.sin6_addr));
 314                                 printf("%-17.17s ",
 315                                     (char *)inet_ntop(AF_INET6,
 316                                         &sin6->sin6_addr,
 317                                         ntop_buf, sizeof(ntop_buf)));
 318
 319                                 network_layer = 1;
 320                                 break;
 321 #endif /*INET6*/
 322                         case AF_IPX:
 323                                 {
 324                                 struct sockaddr_ipx *sipx =
 325                                         (struct sockaddr_ipx *)sa;
 326                                 u_long net;
 327                                 char netnum[10];
 328
 329                                 *(union ipx_net *) &net = sipx->sipx_addr.x_net;
 330                                 sprintf(netnum, "%lx", (u_long)ntohl(net));
 331                                 printf("ipx:%-8s  ", netnum);
 332 /*                              printf("ipx:%-8s ", netname(net, 0L)); */
 333                                 printf("%-15s ",
 334                                     ipx_phost((struct sockaddr *)sipx));
 335                                 }
 336                                 break;
 337
 338                         case AF_APPLETALK:
 339                                 printf("atalk:%-12.12s ",atalk_print(sa,0x10) );
 340                                 printf("%-9.9s  ",atalk_print(sa,0x0b) );
 341                                 break;
 342 #ifdef NS
 343                         case AF_NS:
 344                                 {
 345                                 struct sockaddr_ns *sns =
 346                                         (struct sockaddr_ns *)sa;
 347                                 u_long net;
 348                                 char netnum[10];
 349
 350                                 *(union ns_net *) &net = sns->sns_addr.x_net;
 351                                 sprintf(netnum, "%lxH", ntohl(net));
 352                                 upHex(netnum);
 353                                 printf("ns:%-8s ", netnum);
 354                                 printf("%-15s ",
 355                                     ns_phost((struct sockaddr *)sns));
 356                                 }
 357                                 break;
 358 #endif
 359                         case AF_LINK:
 360                                 {
 361                                 struct sockaddr_dl *sdl =
 362                                         (struct sockaddr_dl *)sa;
 363                                 char linknum[10];
 364                                 cp = (char *)LLADDR(sdl);
 365                                 n = sdl->sdl_alen;
 366                                 sprintf(linknum, "<Link#%d>", sdl->sdl_index);
 367                                 m = printf("%-11.11s ", linknum);
 368                                 }
 369                                 goto hexprint;
 370                         default:
 371                                 m = printf("(%d)", sa->sa_family);
 372                                 for (cp = sa->sa_len + (char *)sa;
 373                                         --cp > sa->sa_data && (*cp == 0);) {}
 374                                 n = cp - sa->sa_data + 1;
 375                                 cp = sa->sa_data;
 376                         hexprint:
 377                                 while (--n >= 0)
 378                                         m += printf("%02x%c", *cp++ & 0xff,
 379                                                     n > 0 ? ':' : ' ');
 380                                 m = 30 - m;
 381                                 while (m-- > 0)
 382                                         putchar(' ');
 383
 384                                 link_layer = 1;
 385                                 break;
 386                         }
 387
 388                         /*
 389                          * Fixup the statistics for interfaces that
 390                          * update stats for their network addresses
 391                          */
 392                         if (network_layer) {
 393                                 opackets = ifaddr.in.ia_ifa.if_opackets;
 394                                 ipackets = ifaddr.in.ia_ifa.if_ipackets;
 395                                 obytes = ifaddr.in.ia_ifa.if_obytes;
 396                                 ibytes = ifaddr.in.ia_ifa.if_ibytes;
 397                         }
 398
 399                         ifaddraddr = (u_long)TAILQ_NEXT(&ifaddr.ifa, ifa_link);
 400                 }
 401
 402                 show_stat("lu", 8, ipackets, link_layer|network_layer);
 403                 printf(" ");
 404                 show_stat("lu", 5, ierrors, link_layer);
 405                 printf(" ");
 406                 if (bflag) {
 407                         show_stat("lu", 10, ibytes, link_layer|network_layer);
 408                         printf(" ");
 409                 }
 410                 show_stat("lu", 8, opackets, link_layer|network_layer);
 411                 printf(" ");
 412                 show_stat("lu", 5, oerrors, link_layer);
 413                 printf(" ");
 414                 if (bflag) {
 415                         show_stat("lu", 10, obytes, link_layer|network_layer);
 416                         printf(" ");
 417                 }
 418                 show_stat("lu", 5, collisions, link_layer);
 419                 if (tflag) {
 420                         printf(" ");
 421                         show_stat("d", 3, timer, link_layer);
 422                 }
 423                 if (dflag) {
 424                         printf(" ");
 425                         show_stat("d", 3, drops, link_layer);
 426                 }
 427                 putchar('\n');
 428                 if (aflag && ifaddrfound) {
 429                         /*
 430                          * Print family's multicast addresses
 431                          */
 432                         u_long multiaddr;
 433                         struct ifmultiaddr ifma;
 434                         union {
 435                                 struct sockaddr sa;
 436                                 struct sockaddr_in in;
 437 #ifdef INET6
 438                                 struct sockaddr_in6 in6;
 439 #endif /* INET6 */
 440                                 struct sockaddr_dl dl;
 441                         } msa;
 442                         const char *fmt;
 443
 444                         for(multiaddr = (u_long)ifnet.if_multiaddrs.lh_first;
 445                             multiaddr;
 446                             multiaddr = (u_long)ifma.ifma_link.le_next) {
 447                                 if (kread(multiaddr, (char *)&ifma,
 448                                           sizeof ifma))
 449                                         break;
 450                                 if (kread((u_long)ifma.ifma_addr, (char *)&msa,
 451                                           sizeof msa))
 452                                         break;
 453                                 if (msa.sa.sa_family != sa->sa_family)
 454                                         continue;
 455
 456                                 fmt = 0;
 457                                 switch (msa.sa.sa_family) {
 458                                 case AF_INET:
 459                                         fmt = routename(msa.in.sin_addr.s_addr);
 460                                         break;
 461 #ifdef INET6
 462                                 case AF_INET6:
 463                                         printf("%23s %-19.19s(refs: %d)\n", "",
 464                                                inet_ntop(AF_INET6,
 465                                                          &msa.in6.sin6_addr,
 466                                                          ntop_buf,
 467                                                          sizeof(ntop_buf)),
 468                                                ifma.ifma_refcount);
 469                                         break;
 470 #endif /* INET6 */
 471                                 case AF_LINK:
 472                                         switch (msa.dl.sdl_type) {
 473                                         case IFT_ETHER:
 474                                         case IFT_FDDI:
 475                                                 fmt = ether_ntoa(
 476                                                         (struct ether_addr *)
 477                                                         LLADDR(&msa.dl));
 478                                                 break;
 479                                         }
 480                                         break;
 481                                 }
 482                                 if (fmt)
 483                                         printf("%23s %s\n", "", fmt);
 484                         }
 485                 }
 486         }
 487 }
 488
 489 struct  iftot {
 490         SLIST_ENTRY(iftot) chain;
 491         char    ift_name[IFNAMSIZ];     /* interface name */
 492         u_long  ift_ip;                 /* input packets */
 493         u_long  ift_ie;                 /* input errors */
 494         u_long  ift_op;                 /* output packets */
 495         u_long  ift_oe;                 /* output errors */
 496         u_long  ift_co;                 /* collisions */
 497         u_int   ift_dr;                 /* drops */
 498         u_long  ift_ib;                 /* input bytes */
 499         u_long  ift_ob;                 /* output bytes */
 500 };
 501
 502 u_char  signalled;                      /* set if alarm goes off "early" */
 503
 504 /*
 505  * Print a running summary of interface statistics.
 506  * Repeat display every interval seconds, showing statistics
 507  * collected over that interval.  Assumes that interval is non-zero.
 508  * First line printed at top of screen is always cumulative.
 509  * XXX - should be rewritten to use ifmib(4).
 510  */
 511 static void
 512 sidewaysintpr(unsigned interval, u_long off)
 513 {
 514         struct ifnet ifnet;
 515         u_long firstifnet;
 516         struct ifnethead ifnethead;
 517         struct iftot *iftot, *ip, *ipn, *total, *sum, *interesting;
 518         register int line;
 519         int oldmask, first;
 520         u_long interesting_off;
 521
 522         if (kread(off, (char *)&ifnethead, sizeof ifnethead))
 523                 return;
 524         firstifnet = (u_long)TAILQ_FIRST(&ifnethead);
 525
 526         if ((iftot = malloc(sizeof(struct iftot))) == NULL) {
 527                 printf("malloc failed\n");
 528                 exit(1);
 529         }
 530         memset(iftot, 0, sizeof(struct iftot));
 531
 532         interesting = NULL;
 533         interesting_off = 0;
 534         for (off = firstifnet, ip = iftot; off;) {
 535                 char name[IFNAMSIZ];
 536
 537                 if (kread(off, (char *)&ifnet, sizeof ifnet))
 538                         break;
 539                 strlcpy(name, ifnet.if_xname, sizeof(name));
 540                 if (interface && strcmp(name, interface) == 0) {
 541                         interesting = ip;
 542                         interesting_off = off;
 543                 }
 544                 snprintf(ip->ift_name, 16, "(%s)", name);;
 545                 if ((ipn = malloc(sizeof(struct iftot))) == NULL) {
 546                         printf("malloc failed\n");
 547                         exit(1);
 548                 }
 549                 memset(ipn, 0, sizeof(struct iftot));
 550                 SLIST_NEXT(ip, chain) = ipn;
 551                 ip = ipn;
 552                 off = (u_long)TAILQ_NEXT(&ifnet, if_link);
 553         }
 554         if ((total = malloc(sizeof(struct iftot))) == NULL) {
 555                 printf("malloc failed\n");
 556                 exit(1);
 557         }
 558         memset(total, 0, sizeof(struct iftot));
 559         if ((sum = malloc(sizeof(struct iftot))) == NULL) {
 560                 printf("malloc failed\n");
 561                 exit(1);
 562         }
 563         memset(sum, 0, sizeof(struct iftot));
 564
 565
 566         (void)signal(SIGALRM, catchalarm);
 567         signalled = NO;
 568         (void)alarm(interval);
 569         first = 1;
 570 banner:
 571         printf("%17s %14s %16s", "input",
 572             interesting ? interesting->ift_name : "(Total)", "output");
 573         putchar('\n');
 574         printf("%10s %5s %10s %10s %5s %10s %5s",
 575             "packets", "errs", "bytes", "packets", "errs", "bytes", "colls");
 576         if (dflag)
 577                 printf(" %5.5s", "drops");
 578         putchar('\n');
 579         fflush(stdout);
 580         line = 0;
 581 loop:
 582         if (interesting != NULL) {
 583                 ip = interesting;
 584                 if (kread(interesting_off, (char *)&ifnet, sizeof ifnet)) {
 585                         printf("???\n");
 586                         exit(1);
 587                 };
 588                 if (!first) {
 589                         printf("%10lu %5lu %10lu %10lu %5lu %10lu %5lu",
 590                                 ifnet.if_ipackets - ip->ift_ip,
 591                                 ifnet.if_ierrors - ip->ift_ie,
 592                                 ifnet.if_ibytes - ip->ift_ib,
 593                                 ifnet.if_opackets - ip->ift_op,
 594                                 ifnet.if_oerrors - ip->ift_oe,
 595                                 ifnet.if_obytes - ip->ift_ob,
 596                                 ifnet.if_collisions - ip->ift_co);
 597                         if (dflag)
 598                                 printf(" %5u", ifnet.if_snd.ifq_drops - ip->ift_dr);
 599                 }
 600                 ip->ift_ip = ifnet.if_ipackets;
 601                 ip->ift_ie = ifnet.if_ierrors;
 602                 ip->ift_ib = ifnet.if_ibytes;
 603                 ip->ift_op = ifnet.if_opackets;
 604                 ip->ift_oe = ifnet.if_oerrors;
 605                 ip->ift_ob = ifnet.if_obytes;
 606                 ip->ift_co = ifnet.if_collisions;
 607                 ip->ift_dr = ifnet.if_snd.ifq_drops;
 608         } else {
 609                 sum->ift_ip = 0;
 610                 sum->ift_ie = 0;
 611                 sum->ift_ib = 0;
 612                 sum->ift_op = 0;
 613                 sum->ift_oe = 0;
 614                 sum->ift_ob = 0;
 615                 sum->ift_co = 0;
 616                 sum->ift_dr = 0;
 617                 for (off = firstifnet, ip = iftot;
 618                      off && SLIST_NEXT(ip, chain) != NULL;
 619                      ip = SLIST_NEXT(ip, chain)) {
 620                         if (kread(off, (char *)&ifnet, sizeof ifnet)) {
 621                                 off = 0;
 622                                 continue;
 623                         }
 624                         sum->ift_ip += ifnet.if_ipackets;
 625                         sum->ift_ie += ifnet.if_ierrors;
 626                         sum->ift_ib += ifnet.if_ibytes;
 627                         sum->ift_op += ifnet.if_opackets;
 628                         sum->ift_oe += ifnet.if_oerrors;
 629                         sum->ift_ob += ifnet.if_obytes;
 630                         sum->ift_co += ifnet.if_collisions;
 631                         sum->ift_dr += ifnet.if_snd.ifq_drops;
 632                         off = (u_long)TAILQ_NEXT(&ifnet, if_link);
 633                 }
 634                 if (!first) {
 635                         printf("%10lu %5lu %10lu %10lu %5lu %10lu %5lu",
 636                                 sum->ift_ip - total->ift_ip,
 637                                 sum->ift_ie - total->ift_ie,
 638                                 sum->ift_ib - total->ift_ib,
 639                                 sum->ift_op - total->ift_op,
 640                                 sum->ift_oe - total->ift_oe,
 641                                 sum->ift_ob - total->ift_ob,
 642                                 sum->ift_co - total->ift_co);
 643                         if (dflag)
 644                                 printf(" %5u", sum->ift_dr - total->ift_dr);
 645                 }
 646                 *total = *sum;
 647         }
 648         if (!first)
 649                 putchar('\n');
 650         fflush(stdout);
 651         oldmask = sigblock(sigmask(SIGALRM));
 652         if (! signalled) {
 653                 sigpause(0);
 654         }
 655         sigsetmask(oldmask);
 656         signalled = NO;
 657         (void)alarm(interval);
 658         line++;
 659         first = 0;
 660         if (line == 21)
 661                 goto banner;
 662         else
 663                 goto loop;
 664         /*NOTREACHED*/
 665 }
 666
 667 /*
 668  * Called if an interval expires before sidewaysintpr has completed a loop.
 669  * Sets a flag to not wait for the alarm.
 670  */
 671 static void
 672 catchalarm(int signo __unused)
 673 {
 674         signalled = YES;
 675 }