The Tcpdump Group git mirrors - tcpdump/blob - addrtoname.c

   1 /*
   2  * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
   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: (1) source code distributions
   7  * retain the above copyright notice and this paragraph in its entirety, (2)
   8  * distributions including binary code include the above copyright notice and
   9  * this paragraph in its entirety in the documentation or other materials
  10  * provided with the distribution, and (3) all advertising materials mentioning
  11  * features or use of this software display the following acknowledgement:
  12  * ``This product includes software developed by the University of California,
  13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  14  * the University nor the names of its contributors may be used to endorse
  15  * or promote products derived from this software without specific prior
  16  * written permission.
  17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  20  *
  21  *  Internet, ethernet, port, and protocol string to address
  22  *  and address to string conversion routines
  23  */
  24 #ifndef lint
  25 static const char rcsid[] =
  26     "@(#) $Header: /tcpdump/master/tcpdump/addrtoname.c,v 1.67 2000-01-19 05:24:16 itojun Exp $ (LBL)";
  27 #endif
  28
  29 #ifdef HAVE_CONFIG_H
  30 #include "config.h"
  31 #endif
  32
  33 #include <sys/types.h>
  34 #include <sys/socket.h>
  35 #include <sys/time.h>
  36
  37 #if __STDC__
  38 struct mbuf;
  39 struct rtentry;
  40 #endif
  41 #include <net/if.h>
  42
  43 #include <netinet/in.h>
  44 #include <netinet/if_ether.h>
  45
  46 #ifdef INET6
  47 #include <netinet/ip6.h>
  48 #endif
  49
  50 #include <arpa/inet.h>
  51
  52 #include <ctype.h>
  53 #include <netdb.h>
  54 #include <pcap.h>
  55 #include <pcap-namedb.h>
  56 #ifdef HAVE_MALLOC_H
  57 #include <malloc.h>
  58 #endif
  59 #ifdef HAVE_MEMORY_H
  60 #include <memory.h>
  61 #endif
  62 #include <signal.h>
  63 #include <stdio.h>
  64 #include <string.h>
  65 #include <stdlib.h>
  66 #include <unistd.h>
  67
  68 #include "interface.h"
  69 #include "addrtoname.h"
  70 #include "llc.h"
  71 #include "savestr.h"
  72 #include "setsignal.h"
  73
  74 /* Forwards */
  75 static RETSIGTYPE nohostname(int);
  76
  77 /*
  78  * hash tables for whatever-to-name translations
  79  */
  80
  81 #define HASHNAMESIZE 4096
  82
  83 struct hnamemem {
  84         u_int32_t addr;
  85         char *name;
  86         struct hnamemem *nxt;
  87 };
  88
  89 struct hnamemem hnametable[HASHNAMESIZE];
  90 struct hnamemem tporttable[HASHNAMESIZE];
  91 struct hnamemem uporttable[HASHNAMESIZE];
  92 struct hnamemem eprototable[HASHNAMESIZE];
  93 struct hnamemem dnaddrtable[HASHNAMESIZE];
  94 struct hnamemem llcsaptable[HASHNAMESIZE];
  95
  96 #ifdef INET6
  97 struct h6namemem {
  98         struct in6_addr addr;
  99         char *name;
 100         struct h6namemem *nxt;
 101 };
 102
 103 struct h6namemem h6nametable[HASHNAMESIZE];
 104 #endif /* INET6 */
 105
 106 struct enamemem {
 107         u_short e_addr0;
 108         u_short e_addr1;
 109         u_short e_addr2;
 110         char *e_name;
 111         u_char *e_nsap;                 /* used only for nsaptable[] */
 112         struct enamemem *e_nxt;
 113 };
 114
 115 struct enamemem enametable[HASHNAMESIZE];
 116 struct enamemem nsaptable[HASHNAMESIZE];
 117
 118 struct protoidmem {
 119         u_int32_t p_oui;
 120         u_short p_proto;
 121         char *p_name;
 122         struct protoidmem *p_nxt;
 123 };
 124
 125 struct protoidmem protoidtable[HASHNAMESIZE];
 126
 127 /*
 128  * A faster replacement for inet_ntoa().
 129  */
 130 char *
 131 intoa(u_int32_t addr)
 132 {
 133         register char *cp;
 134         register u_int byte;
 135         register int n;
 136         static char buf[sizeof(".xxx.xxx.xxx.xxx")];
 137
 138         NTOHL(addr);
 139         cp = &buf[sizeof buf];
 140         *--cp = '\0';
 141
 142         n = 4;
 143         do {
 144                 byte = addr & 0xff;
 145                 *--cp = byte % 10 + '0';
 146                 byte /= 10;
 147                 if (byte > 0) {
 148                         *--cp = byte % 10 + '0';
 149                         byte /= 10;
 150                         if (byte > 0)
 151                                 *--cp = byte + '0';
 152                 }
 153                 *--cp = '.';
 154                 addr >>= 8;
 155         } while (--n > 0);
 156
 157         return cp + 1;
 158 }
 159
 160 static u_int32_t f_netmask;
 161 static u_int32_t f_localnet;
 162 static u_int32_t netmask;
 163
 164 /*
 165  * "getname" is written in this atrocious way to make sure we don't
 166  * wait forever while trying to get hostnames from yp.
 167  */
 168 #include <setjmp.h>
 169
 170 jmp_buf getname_env;
 171
 172 static RETSIGTYPE
 173 nohostname(int signo)
 174 {
 175         longjmp(getname_env, 1);
 176 }
 177
 178 /*
 179  * Return a name for the IP address pointed to by ap.  This address
 180  * is assumed to be in network byte order.
 181  */
 182 char *
 183 getname(const u_char *ap)
 184 {
 185         register struct hostent *hp;
 186         u_int32_t addr;
 187         static struct hnamemem *p;              /* static for longjmp() */
 188
 189 #ifndef LBL_ALIGN
 190         addr = *(const u_int32_t *)ap;
 191 #else
 192         memcpy(&addr, ap, sizeof(addr));
 193 #endif
 194         p = &hnametable[addr & (HASHNAMESIZE-1)];
 195         for (; p->nxt; p = p->nxt) {
 196                 if (p->addr == addr)
 197                         return (p->name);
 198         }
 199         p->addr = addr;
 200         p->nxt = newhnamemem();
 201
 202         /*
 203          * Only print names when:
 204          *      (1) -n was not given.
 205          *      (2) Address is foreign and -f was given. (If -f was not
 206          *          give, f_netmask and f_local are 0 and the test
 207          *          evaluates to true)
 208          *      (3) -a was given or the host portion is not all ones
 209          *          nor all zeros (i.e. not a network or broadcast address)
 210          */
 211         if (!nflag &&
 212             (addr & f_netmask) == f_localnet &&
 213             (aflag ||
 214             !((addr & ~netmask) == 0 || (addr | netmask) == 0xffffffff))) {
 215                 if (!setjmp(getname_env)) {
 216                         (void)setsignal(SIGALRM, nohostname);
 217                         (void)alarm(20);
 218                         hp = gethostbyaddr((char *)&addr, 4, AF_INET);
 219                         (void)alarm(0);
 220                         if (hp) {
 221                                 char *dotp;
 222
 223                                 p->name = savestr(hp->h_name);
 224                                 if (Nflag) {
 225                                         /* Remove domain qualifications */
 226                                         dotp = strchr(p->name, '.');
 227                                         if (dotp)
 228                                                 *dotp = '\0';
 229                                 }
 230                                 return (p->name);
 231                         }
 232                 }
 233         }
 234         p->name = savestr(intoa(addr));
 235         return (p->name);
 236 }
 237
 238 #ifdef INET6
 239 /*
 240  * Return a name for the IP6 address pointed to by ap.  This address
 241  * is assumed to be in network byte order.
 242  */
 243 char *
 244 getname6(const u_char *ap)
 245 {
 246         register struct hostent *hp;
 247         struct in6_addr addr;
 248         static struct h6namemem *p;             /* static for longjmp() */
 249         register char *cp;
 250         char ntop_buf[INET6_ADDRSTRLEN];
 251
 252         memcpy(&addr, ap, sizeof(addr));
 253         p = &h6nametable[*(u_int16_t *)&addr.s6_addr[14] & (HASHNAMESIZE-1)];
 254         for (; p->nxt; p = p->nxt) {
 255                 if (memcmp(&p->addr, &addr, sizeof(addr)) == 0)
 256                         return (p->name);
 257         }
 258         p->addr = addr;
 259         p->nxt = newh6namemem();
 260
 261         /*
 262          * Only print names when:
 263          *      (1) -n was not given.
 264          *      (2) Address is foreign and -f was given. (If -f was not
 265          *          give, f_netmask and f_local are 0 and the test
 266          *          evaluates to true)
 267          *      (3) -a was given or the host portion is not all ones
 268          *          nor all zeros (i.e. not a network or broadcast address)
 269          */
 270         if (!nflag
 271 #if 0
 272         &&
 273             (addr & f_netmask) == f_localnet &&
 274             (aflag ||
 275             !((addr & ~netmask) == 0 || (addr | netmask) == 0xffffffff))
 276 #endif
 277             ) {
 278                 if (!setjmp(getname_env)) {
 279                         (void)setsignal(SIGALRM, nohostname);
 280                         (void)alarm(20);
 281                         hp = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET6);
 282                         (void)alarm(0);
 283                         if (hp) {
 284                                 char *dotp;
 285
 286                                 p->name = savestr(hp->h_name);
 287                                 if (Nflag) {
 288                                         /* Remove domain qualifications */
 289                                         dotp = strchr(p->name, '.');
 290                                         if (dotp)
 291                                                 *dotp = '\0';
 292                                 }
 293                                 return (p->name);
 294                         }
 295                 }
 296         }
 297         cp = (char *)inet_ntop(AF_INET6, &addr, ntop_buf, sizeof(ntop_buf));
 298         p->name = savestr(cp);
 299         return (p->name);
 300 }
 301 #endif /* INET6 */
 302
 303 static char hex[] = "0123456789abcdef";
 304
 305
 306 /* Find the hash node that corresponds the ether address 'ep' */
 307
 308 static inline struct enamemem *
 309 lookup_emem(const u_char *ep)
 310 {
 311         register u_int i, j, k;
 312         struct enamemem *tp;
 313
 314         k = (ep[0] << 8) | ep[1];
 315         j = (ep[2] << 8) | ep[3];
 316         i = (ep[4] << 8) | ep[5];
 317
 318         tp = &enametable[(i ^ j) & (HASHNAMESIZE-1)];
 319         while (tp->e_nxt)
 320                 if (tp->e_addr0 == i &&
 321                     tp->e_addr1 == j &&
 322                     tp->e_addr2 == k)
 323                         return tp;
 324                 else
 325                         tp = tp->e_nxt;
 326         tp->e_addr0 = i;
 327         tp->e_addr1 = j;
 328         tp->e_addr2 = k;
 329         tp->e_nxt = (struct enamemem *)calloc(1, sizeof(*tp));
 330         if (tp->e_nxt == NULL)
 331                 error("lookup_emem: calloc");
 332
 333         return tp;
 334 }
 335
 336 /* Find the hash node that corresponds the NSAP 'nsap' */
 337
 338 static inline struct enamemem *
 339 lookup_nsap(register const u_char *nsap)
 340 {
 341         register u_int i, j, k;
 342         int nlen = *nsap;
 343         struct enamemem *tp;
 344         const u_char *ensap = nsap + nlen - 6;
 345
 346         if (nlen > 6) {
 347                 k = (ensap[0] << 8) | ensap[1];
 348                 j = (ensap[2] << 8) | ensap[3];
 349                 i = (ensap[4] << 8) | ensap[5];
 350         }
 351         else
 352                 i = j = k = 0;
 353
 354         tp = &nsaptable[(i ^ j) & (HASHNAMESIZE-1)];
 355         while (tp->e_nxt)
 356                 if (tp->e_addr0 == i &&
 357                     tp->e_addr1 == j &&
 358                     tp->e_addr2 == k &&
 359                     tp->e_nsap[0] == nlen &&
 360                     memcmp((char *)&(nsap[1]),
 361                         (char *)&(tp->e_nsap[1]), nlen) == 0)
 362                         return tp;
 363                 else
 364                         tp = tp->e_nxt;
 365         tp->e_addr0 = i;
 366         tp->e_addr1 = j;
 367         tp->e_addr2 = k;
 368         tp->e_nsap = (u_char *)malloc(nlen + 1);
 369         if (tp->e_nsap == NULL)
 370                 error("lookup_nsap: malloc");
 371         memcpy((char *)tp->e_nsap, (char *)nsap, nlen + 1);
 372         tp->e_nxt = (struct enamemem *)calloc(1, sizeof(*tp));
 373         if (tp->e_nxt == NULL)
 374                 error("lookup_nsap: calloc");
 375
 376         return tp;
 377 }
 378
 379 /* Find the hash node that corresponds the protoid 'pi'. */
 380
 381 static inline struct protoidmem *
 382 lookup_protoid(const u_char *pi)
 383 {
 384         register u_int i, j;
 385         struct protoidmem *tp;
 386
 387         /* 5 octets won't be aligned */
 388         i = (((pi[0] << 8) + pi[1]) << 8) + pi[2];
 389         j =   (pi[3] << 8) + pi[4];
 390         /* XXX should be endian-insensitive, but do big-endian testing  XXX */
 391
 392         tp = &protoidtable[(i ^ j) & (HASHNAMESIZE-1)];
 393         while (tp->p_nxt)
 394                 if (tp->p_oui == i && tp->p_proto == j)
 395                         return tp;
 396                 else
 397                         tp = tp->p_nxt;
 398         tp->p_oui = i;
 399         tp->p_proto = j;
 400         tp->p_nxt = (struct protoidmem *)calloc(1, sizeof(*tp));
 401         if (tp->p_nxt == NULL)
 402                 error("lookup_protoid: calloc");
 403
 404         return tp;
 405 }
 406
 407 char *
 408 etheraddr_string(register const u_char *ep)
 409 {
 410         register u_int i, j;
 411         register char *cp;
 412         register struct enamemem *tp;
 413         char buf[sizeof("00:00:00:00:00:00")];
 414
 415         tp = lookup_emem(ep);
 416         if (tp->e_name)
 417                 return (tp->e_name);
 418 #ifdef HAVE_ETHER_NTOHOST
 419         if (!nflag) {
 420                 char buf[128];
 421                 if (ether_ntohost(buf, (struct ether_addr *)ep) == 0) {
 422                         tp->e_name = savestr(buf);
 423                         return (tp->e_name);
 424                 }
 425         }
 426 #endif
 427         cp = buf;
 428         if ((j = *ep >> 4) != 0)
 429                 *cp++ = hex[j];
 430         *cp++ = hex[*ep++ & 0xf];
 431         for (i = 5; (int)--i >= 0;) {
 432                 *cp++ = ':';
 433                 if ((j = *ep >> 4) != 0)
 434                         *cp++ = hex[j];
 435                 *cp++ = hex[*ep++ & 0xf];
 436         }
 437         *cp = '\0';
 438         tp->e_name = savestr(buf);
 439         return (tp->e_name);
 440 }
 441
 442 char *
 443 etherproto_string(u_short port)
 444 {
 445         register char *cp;
 446         register struct hnamemem *tp;
 447         register u_int32_t i = port;
 448         char buf[sizeof("0000")];
 449
 450         for (tp = &eprototable[i & (HASHNAMESIZE-1)]; tp->nxt; tp = tp->nxt)
 451                 if (tp->addr == i)
 452                         return (tp->name);
 453
 454         tp->addr = i;
 455         tp->nxt = newhnamemem();
 456
 457         cp = buf;
 458         NTOHS(port);
 459         *cp++ = hex[port >> 12 & 0xf];
 460         *cp++ = hex[port >> 8 & 0xf];
 461         *cp++ = hex[port >> 4 & 0xf];
 462         *cp++ = hex[port & 0xf];
 463         *cp++ = '\0';
 464         tp->name = savestr(buf);
 465         return (tp->name);
 466 }
 467
 468 char *
 469 protoid_string(register const u_char *pi)
 470 {
 471         register u_int i, j;
 472         register char *cp;
 473         register struct protoidmem *tp;
 474         char buf[sizeof("00:00:00:00:00")];
 475
 476         tp = lookup_protoid(pi);
 477         if (tp->p_name)
 478                 return tp->p_name;
 479
 480         cp = buf;
 481         if ((j = *pi >> 4) != 0)
 482                 *cp++ = hex[j];
 483         *cp++ = hex[*pi++ & 0xf];
 484         for (i = 4; (int)--i >= 0;) {
 485                 *cp++ = ':';
 486                 if ((j = *pi >> 4) != 0)
 487                         *cp++ = hex[j];
 488                 *cp++ = hex[*pi++ & 0xf];
 489         }
 490         *cp = '\0';
 491         tp->p_name = savestr(buf);
 492         return (tp->p_name);
 493 }
 494
 495 char *
 496 llcsap_string(u_char sap)
 497 {
 498         register struct hnamemem *tp;
 499         register u_int32_t i = sap;
 500         char buf[sizeof("sap 00")];
 501
 502         for (tp = &llcsaptable[i & (HASHNAMESIZE-1)]; tp->nxt; tp = tp->nxt)
 503                 if (tp->addr == i)
 504                         return (tp->name);
 505
 506         tp->addr = i;
 507         tp->nxt = newhnamemem();
 508
 509         snprintf(buf, sizeof(buf), "sap %02x", sap & 0xff);
 510         tp->name = savestr(buf);
 511         return (tp->name);
 512 }
 513
 514 char *
 515 isonsap_string(const u_char *nsap)
 516 {
 517         register u_int i, nlen = nsap[0];
 518         register char *cp;
 519         register struct enamemem *tp;
 520
 521         tp = lookup_nsap(nsap);
 522         if (tp->e_name)
 523                 return tp->e_name;
 524
 525         tp->e_name = cp = (char *)malloc(nlen * 2 + 2);
 526         if (cp == NULL)
 527                 error("isonsap_string: malloc");
 528
 529         nsap++;
 530         *cp++ = '/';
 531         for (i = nlen; (int)--i >= 0;) {
 532                 *cp++ = hex[*nsap >> 4];
 533                 *cp++ = hex[*nsap++ & 0xf];
 534         }
 535         *cp = '\0';
 536         return (tp->e_name);
 537 }
 538
 539 char *
 540 tcpport_string(u_short port)
 541 {
 542         register struct hnamemem *tp;
 543         register u_int32_t i = port;
 544         char buf[sizeof("00000")];
 545
 546         for (tp = &tporttable[i & (HASHNAMESIZE-1)]; tp->nxt; tp = tp->nxt)
 547                 if (tp->addr == i)
 548                         return (tp->name);
 549
 550         tp->addr = i;
 551         tp->nxt = newhnamemem();
 552
 553         (void)snprintf(buf, sizeof(buf), "%u", i);
 554         tp->name = savestr(buf);
 555         return (tp->name);
 556 }
 557
 558 char *
 559 udpport_string(register u_short port)
 560 {
 561         register struct hnamemem *tp;
 562         register u_int32_t i = port;
 563         char buf[sizeof("00000")];
 564
 565         for (tp = &uporttable[i & (HASHNAMESIZE-1)]; tp->nxt; tp = tp->nxt)
 566                 if (tp->addr == i)
 567                         return (tp->name);
 568
 569         tp->addr = i;
 570         tp->nxt = newhnamemem();
 571
 572         (void)snprintf(buf, sizeof(buf), "%u", i);
 573         tp->name = savestr(buf);
 574         return (tp->name);
 575 }
 576
 577 static void
 578 init_servarray(void)
 579 {
 580         struct servent *sv;
 581         register struct hnamemem *table;
 582         register int i;
 583         char buf[sizeof("0000000000")];
 584
 585         while ((sv = getservent()) != NULL) {
 586                 int port = ntohs(sv->s_port);
 587                 i = port & (HASHNAMESIZE-1);
 588                 if (strcmp(sv->s_proto, "tcp") == 0)
 589                         table = &tporttable[i];
 590                 else if (strcmp(sv->s_proto, "udp") == 0)
 591                         table = &uporttable[i];
 592                 else
 593                         continue;
 594
 595                 while (table->name)
 596                         table = table->nxt;
 597                 if (nflag) {
 598                         (void)snprintf(buf, sizeof(buf), "%d", port);
 599                         table->name = savestr(buf);
 600                 } else
 601                         table->name = savestr(sv->s_name);
 602                 table->addr = port;
 603                 table->nxt = newhnamemem();
 604         }
 605         endservent();
 606 }
 607
 608 /*XXX from libbpfc.a */
 609 extern struct eproto {
 610         char *s;
 611         u_short p;
 612 } eproto_db[];
 613
 614 static void
 615 init_eprotoarray(void)
 616 {
 617         register int i;
 618         register struct hnamemem *table;
 619
 620         for (i = 0; eproto_db[i].s; i++) {
 621                 int j = ntohs(eproto_db[i].p) & (HASHNAMESIZE-1);
 622                 table = &eprototable[j];
 623                 while (table->name)
 624                         table = table->nxt;
 625                 table->name = eproto_db[i].s;
 626                 table->addr = ntohs(eproto_db[i].p);
 627                 table->nxt = newhnamemem();
 628         }
 629 }
 630
 631 /*
 632  * SNAP proto IDs with org code 0:0:0 are actually encapsulated Ethernet
 633  * types.
 634  */
 635 static void
 636 init_protoidarray(void)
 637 {
 638         register int i;
 639         register struct protoidmem *tp;
 640         u_char protoid[5];
 641
 642         protoid[0] = 0;
 643         protoid[1] = 0;
 644         protoid[2] = 0;
 645         for (i = 0; eproto_db[i].s; i++) {
 646                 u_short etype = htons(eproto_db[i].p);
 647
 648                 memcpy((char *)&protoid[3], (char *)&etype, 2);
 649                 tp = lookup_protoid(protoid);
 650                 tp->p_name = savestr(eproto_db[i].s);
 651         }
 652 }
 653
 654 static struct etherlist {
 655         u_char addr[6];
 656         char *name;
 657 } etherlist[] = {
 658         {{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }, "Broadcast" },
 659         {{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, NULL }
 660 };
 661
 662 /*
 663  * Initialize the ethers hash table.  We take two different approaches
 664  * depending on whether or not the system provides the ethers name
 665  * service.  If it does, we just wire in a few names at startup,
 666  * and etheraddr_string() fills in the table on demand.  If it doesn't,
 667  * then we suck in the entire /etc/ethers file at startup.  The idea
 668  * is that parsing the local file will be fast, but spinning through
 669  * all the ethers entries via NIS & next_etherent might be very slow.
 670  *
 671  * XXX pcap_next_etherent doesn't belong in the pcap interface, but
 672  * since the pcap module already does name-to-address translation,
 673  * it's already does most of the work for the ethernet address-to-name
 674  * translation, so we just pcap_next_etherent as a convenience.
 675  */
 676 static void
 677 init_etherarray(void)
 678 {
 679         register struct etherlist *el;
 680         register struct enamemem *tp;
 681 #ifdef HAVE_ETHER_NTOHOST
 682         char name[256];
 683 #else
 684         register struct pcap_etherent *ep;
 685         register FILE *fp;
 686
 687         /* Suck in entire ethers file */
 688         fp = fopen(PCAP_ETHERS_FILE, "r");
 689         if (fp != NULL) {
 690                 while ((ep = pcap_next_etherent(fp)) != NULL) {
 691                         tp = lookup_emem(ep->addr);
 692                         tp->e_name = savestr(ep->name);
 693                 }
 694                 (void)fclose(fp);
 695         }
 696 #endif
 697
 698         /* Hardwire some ethernet names */
 699         for (el = etherlist; el->name != NULL; ++el) {
 700                 tp = lookup_emem(el->addr);
 701                 /* Don't override existing name */
 702                 if (tp->e_name != NULL)
 703                         continue;
 704
 705 #ifdef HAVE_ETHER_NTOHOST
 706                 /* Use yp/nis version of name if available */
 707                 if (ether_ntohost(name, (struct ether_addr *)el->addr) == 0) {
 708                         tp->e_name = savestr(name);
 709                         continue;
 710                 }
 711 #endif
 712                 tp->e_name = el->name;
 713         }
 714 }
 715
 716 static struct tok llcsap_db[] = {
 717         { LLCSAP_NULL,          "null" },
 718         { LLCSAP_8021B_I,       "802.1b-gsap" },
 719         { LLCSAP_8021B_G,       "802.1b-isap" },
 720         { LLCSAP_IP,            "ip-sap" },
 721         { LLCSAP_PROWAYNM,      "proway-nm" },
 722         { LLCSAP_8021D,         "802.1d" },
 723         { LLCSAP_RS511,         "eia-rs511" },
 724         { LLCSAP_ISO8208,       "x.25/llc2" },
 725         { LLCSAP_PROWAY,        "proway" },
 726         { LLCSAP_ISONS,         "iso-clns" },
 727         { LLCSAP_GLOBAL,        "global" },
 728         { 0,                    NULL }
 729 };
 730
 731 static void
 732 init_llcsaparray(void)
 733 {
 734         register int i;
 735         register struct hnamemem *table;
 736
 737         for (i = 0; llcsap_db[i].s != NULL; i++) {
 738                 table = &llcsaptable[llcsap_db[i].v];
 739                 while (table->name)
 740                         table = table->nxt;
 741                 table->name = llcsap_db[i].s;
 742                 table->addr = llcsap_db[i].v;
 743                 table->nxt = newhnamemem();
 744         }
 745 }
 746
 747 /*
 748  * Initialize the address to name translation machinery.  We map all
 749  * non-local IP addresses to numeric addresses if fflag is true (i.e.,
 750  * to prevent blocking on the nameserver).  localnet is the IP address
 751  * of the local network.  mask is its subnet mask.
 752  */
 753 void
 754 init_addrtoname(u_int32_t localnet, u_int32_t mask)
 755 {
 756         netmask = mask;
 757         if (fflag) {
 758                 f_localnet = localnet;
 759                 f_netmask = mask;
 760         }
 761         if (nflag)
 762                 /*
 763                  * Simplest way to suppress names.
 764                  */
 765                 return;
 766
 767         init_etherarray();
 768         init_servarray();
 769         init_eprotoarray();
 770         init_llcsaparray();
 771         init_protoidarray();
 772 }
 773
 774 char *
 775 dnaddr_string(u_short dnaddr)
 776 {
 777         register struct hnamemem *tp;
 778
 779         for (tp = &dnaddrtable[dnaddr & (HASHNAMESIZE-1)]; tp->nxt != 0;
 780              tp = tp->nxt)
 781                 if (tp->addr == dnaddr)
 782                         return (tp->name);
 783
 784         tp->addr = dnaddr;
 785         tp->nxt = newhnamemem();
 786         if (nflag)
 787                 tp->name = dnnum_string(dnaddr);
 788         else
 789                 tp->name = dnname_string(dnaddr);
 790
 791         return(tp->name);
 792 }
 793
 794 /* Return a zero'ed hnamemem struct and cuts down on calloc() overhead */
 795 struct hnamemem *
 796 newhnamemem(void)
 797 {
 798         register struct hnamemem *p;
 799         static struct hnamemem *ptr = NULL;
 800         static u_int num = 0;
 801
 802         if (num  <= 0) {
 803                 num = 64;
 804                 ptr = (struct hnamemem *)calloc(num, sizeof (*ptr));
 805                 if (ptr == NULL)
 806                         error("newhnamemem: calloc");
 807         }
 808         --num;
 809         p = ptr++;
 810         return (p);
 811 }
 812
 813 #ifdef INET6
 814 /* Return a zero'ed h6namemem struct and cuts down on calloc() overhead */
 815 struct h6namemem *
 816 newh6namemem(void)
 817 {
 818         register struct h6namemem *p;
 819         static struct h6namemem *ptr = NULL;
 820         static u_int num = 0;
 821
 822         if (num  <= 0) {
 823                 num = 64;
 824                 ptr = (struct h6namemem *)calloc(num, sizeof (*ptr));
 825                 if (ptr == NULL)
 826                         error("newh6namemem: calloc");
 827         }
 828         --num;
 829         p = ptr++;
 830         return (p);
 831 }
 832 #endif /* INET6 */