The Tcpdump Group git mirrors - tcpdump/blob - print-atalk.c

   1 /*
   2  * Copyright (c) 1988, 1989, 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
  22 /* \summary: AppleTalk printer */
  23
  24 #include <config.h>
  25
  26 #include "netdissect-stdinc.h"
  27
  28 #include <stdio.h>
  29 #include <string.h>
  30
  31 #define ND_LONGJMP_FROM_TCHECK
  32 #include "netdissect.h"
  33 #include "addrtoname.h"
  34 #include "ethertype.h"
  35 #include "extract.h"
  36 #include "appletalk.h"
  37
  38 /* Datagram Delivery Protocol */
  39
  40 struct atDDP {
  41         nd_uint16_t     length;
  42         nd_uint16_t     checksum;
  43         nd_uint16_t     dstNet;
  44         nd_uint16_t     srcNet;
  45         nd_uint8_t      dstNode;
  46         nd_uint8_t      srcNode;
  47         nd_uint8_t      dstSkt;
  48         nd_uint8_t      srcSkt;
  49         nd_uint8_t      type;
  50 };
  51 #define ddpSize         13
  52
  53 struct atShortDDP {
  54         nd_uint16_t     length;
  55         nd_uint8_t      dstSkt;
  56         nd_uint8_t      srcSkt;
  57         nd_uint8_t      type;
  58 };
  59 #define ddpSSize        5
  60
  61 /* AppleTalk Transaction Protocol */
  62
  63 struct atATP {
  64         nd_uint8_t      control;
  65         nd_uint8_t      bitmap;
  66         nd_uint16_t     transID;
  67         nd_uint32_t     userData;
  68 };
  69
  70 #define atpReqCode      0x40
  71 #define atpRspCode      0x80
  72 #define atpRelCode      0xC0
  73 #define atpXO           0x20
  74 #define atpEOM          0x10
  75 #define atpSTS          0x08
  76
  77 /* Name Binding Protocol */
  78
  79 struct atNBP {
  80         nd_uint8_t      control;
  81         nd_uint8_t      id;
  82 };
  83 #define nbpHeaderSize   2
  84
  85 struct atNBPtuple {
  86         nd_uint16_t     net;
  87         nd_uint8_t      node;
  88         nd_uint8_t      skt;
  89         nd_uint8_t      enumerator;
  90 };
  91 #define nbpTupleSize    5
  92
  93 #define nbpBrRq         0x10
  94 #define nbpLkUp         0x20
  95 #define nbpLkUpReply    0x30
  96 static const struct tok nbp_str[] = {
  97         { nbpBrRq,      "brRq"  },
  98         { nbpLkUp,      "lkup"  },
  99         { nbpLkUpReply, "reply" },
 100         { 0, NULL }
 101 };
 102
 103 #define ddpRTMP         1       /* RTMP type */
 104 #define ddpNBP          2       /* NBP type */
 105 #define ddpATP          3       /* ATP type */
 106 #define ddpECHO         4       /* ECHO type */
 107 #define ddpRTMPrequest  5       /* RTMP request type */
 108 #define ddpIP           22      /* IP type */
 109 #define ddpARP          23      /* ARP type */
 110 #define ddpKLAP         0x4b    /* Kinetics KLAP type */
 111 #define ddpEIGRP        88      /* EIGRP over Appletalk */
 112 static const struct tok type2str[] = {
 113         { ddpRTMP,              "rtmp" },
 114         { ddpRTMPrequest,       "rtmpReq" },
 115         { ddpECHO,              "echo" },
 116         { ddpIP,                "IP" },
 117         { ddpARP,               "ARP" },
 118         { ddpKLAP,              "KLAP" },
 119         { 0,                    NULL }
 120 };
 121
 122 struct aarp {
 123         nd_uint16_t     htype, ptype;
 124         nd_uint8_t      halen, palen;
 125         nd_uint16_t     op;
 126         nd_mac48        hsaddr;
 127         nd_byte         psaddr[4];
 128         nd_mac48        hdaddr;
 129         nd_byte         pdaddr[4];
 130 };
 131
 132 static void atp_print(netdissect_options *, const struct atATP *, u_int);
 133 static void atp_bitmap_print(netdissect_options *, u_char);
 134 static void nbp_print(netdissect_options *, const struct atNBP *, u_int, u_short, u_char, u_char);
 135 static const struct atNBPtuple *nbp_tuple_print(netdissect_options *ndo, const struct atNBPtuple *,
 136                                                 u_short, u_char, u_char);
 137 static const struct atNBPtuple *nbp_name_print(netdissect_options *, const struct atNBPtuple *);
 138 static const char *ataddr_string(netdissect_options *, u_short, u_char);
 139 static void ddp_print(netdissect_options *, const u_char *, u_int, u_int, u_short, u_char, u_char);
 140 static const char *ddpskt_string(netdissect_options *, u_int);
 141
 142 /*
 143  * Print LLAP packets received on a physical LocalTalk interface.
 144  */
 145 void
 146 ltalk_if_print(netdissect_options *ndo,
 147                const struct pcap_pkthdr *h, const u_char *p)
 148 {
 149         ndo->ndo_protocol = "ltalk";
 150         ndo->ndo_ll_hdr_len += llap_print(ndo, p, h->len);
 151 }
 152
 153 /*
 154  * Print AppleTalk LLAP packets.
 155  */
 156 u_int
 157 llap_print(netdissect_options *ndo,
 158            const u_char *bp, u_int length)
 159 {
 160         const struct LAP *lp;
 161         const struct atDDP *dp;
 162         const struct atShortDDP *sdp;
 163         u_short snet;
 164         u_int hdrlen;
 165
 166         ndo->ndo_protocol = "llap";
 167         ND_ICHECKMSG_ZU("LLAP length", length, <, sizeof(*lp));
 168         lp = (const struct LAP *)bp;
 169         bp += sizeof(*lp);
 170         length -= sizeof(*lp);
 171         hdrlen = sizeof(*lp);
 172         switch (GET_U_1(lp->type)) {
 173
 174         case lapShortDDP:
 175                 ndo->ndo_protocol = "sddp";
 176                 ND_ICHECKMSG_U("SDDP length", length, <, ddpSSize);
 177                 sdp = (const struct atShortDDP *)bp;
 178                 ND_PRINT("%s.%s",
 179                     ataddr_string(ndo, 0, GET_U_1(lp->src)),
 180                     ddpskt_string(ndo, GET_U_1(sdp->srcSkt)));
 181                 ND_PRINT(" > %s.%s:",
 182                     ataddr_string(ndo, 0, GET_U_1(lp->dst)),
 183                     ddpskt_string(ndo, GET_U_1(sdp->dstSkt)));
 184                 bp += ddpSSize;
 185                 length -= ddpSSize;
 186                 hdrlen += ddpSSize;
 187                 ddp_print(ndo, bp, length, GET_U_1(sdp->type), 0,
 188                           GET_U_1(lp->src), GET_U_1(sdp->srcSkt));
 189                 break;
 190
 191         case lapDDP:
 192                 ndo->ndo_protocol = "ddp";
 193                 ND_ICHECKMSG_U("DDP length", length, <, ddpSize);
 194                 dp = (const struct atDDP *)bp;
 195                 snet = GET_BE_U_2(dp->srcNet);
 196                 ND_PRINT("%s.%s",
 197                          ataddr_string(ndo, snet, GET_U_1(dp->srcNode)),
 198                          ddpskt_string(ndo, GET_U_1(dp->srcSkt)));
 199                 ND_PRINT(" > %s.%s:",
 200                     ataddr_string(ndo, GET_BE_U_2(dp->dstNet), GET_U_1(dp->dstNode)),
 201                     ddpskt_string(ndo, GET_U_1(dp->dstSkt)));
 202                 bp += ddpSize;
 203                 length -= ddpSize;
 204                 hdrlen += ddpSize;
 205                 ddp_print(ndo, bp, length, GET_U_1(dp->type), snet,
 206                           GET_U_1(dp->srcNode), GET_U_1(dp->srcSkt));
 207                 break;
 208
 209         default:
 210                 ND_PRINT("%u > %u at-lap#%u %u",
 211                     GET_U_1(lp->src), GET_U_1(lp->dst), GET_U_1(lp->type),
 212                     length);
 213                 break;
 214         }
 215         return (hdrlen);
 216 invalid:
 217         nd_print_invalid(ndo);
 218         return length;
 219 }
 220
 221 /*
 222  * Print EtherTalk/TokenTalk packets (or FDDITalk, or whatever it's called
 223  * when it runs over FDDI; yes, I've seen FDDI captures with AppleTalk
 224  * packets in them).
 225  */
 226 void
 227 atalk_print(netdissect_options *ndo,
 228             const u_char *bp, u_int length)
 229 {
 230         const struct atDDP *dp;
 231         u_short snet;
 232
 233         ndo->ndo_protocol = "atalk";
 234         if(!ndo->ndo_eflag)
 235             ND_PRINT("AT ");
 236
 237         ND_ICHECK_U(length, <, ddpSize);
 238         dp = (const struct atDDP *)bp;
 239         snet = GET_BE_U_2(dp->srcNet);
 240         ND_PRINT("%s.%s", ataddr_string(ndo, snet, GET_U_1(dp->srcNode)),
 241                  ddpskt_string(ndo, GET_U_1(dp->srcSkt)));
 242         ND_PRINT(" > %s.%s: ",
 243                ataddr_string(ndo, GET_BE_U_2(dp->dstNet), GET_U_1(dp->dstNode)),
 244                ddpskt_string(ndo, GET_U_1(dp->dstSkt)));
 245         bp += ddpSize;
 246         length -= ddpSize;
 247         ddp_print(ndo, bp, length, GET_U_1(dp->type), snet,
 248                   GET_U_1(dp->srcNode), GET_U_1(dp->srcSkt));
 249         return;
 250 invalid:
 251         nd_print_invalid(ndo);
 252 }
 253
 254 /* XXX should probably pass in the snap header and do checks like arp_print() */
 255 void
 256 aarp_print(netdissect_options *ndo,
 257            const u_char *bp, u_int length)
 258 {
 259         const struct aarp *ap;
 260
 261 #define AT(member) ataddr_string(ndo, \
 262         (GET_U_1(&ap->member[1])<<8)|GET_U_1(&ap->member[2]), \
 263         GET_U_1(&ap->member[3]))
 264
 265         ndo->ndo_protocol = "aarp";
 266         ND_PRINT("aarp ");
 267         ap = (const struct aarp *)bp;
 268         ND_ICHECK_ZU(length, <, sizeof(*ap));
 269         ND_TCHECK_SIZE(ap);
 270         if (GET_BE_U_2(ap->htype) == 1 &&
 271             GET_BE_U_2(ap->ptype) == ETHERTYPE_ATALK &&
 272             GET_U_1(ap->halen) == MAC48_LEN && GET_U_1(ap->palen) == 4)
 273                 switch (GET_BE_U_2(ap->op)) {
 274
 275                 case 1:                         /* request */
 276                         ND_PRINT("who-has %s tell %s", AT(pdaddr), AT(psaddr));
 277                         return;
 278
 279                 case 2:                         /* response */
 280                         ND_PRINT("reply %s is-at %s", AT(psaddr), GET_MAC48_STRING(ap->hsaddr));
 281                         return;
 282
 283                 case 3:                         /* probe (oy!) */
 284                         ND_PRINT("probe %s tell %s", AT(pdaddr), AT(psaddr));
 285                         return;
 286                 }
 287         ND_PRINT("len %u op %u htype %u ptype %#x halen %u palen %u",
 288             length, GET_BE_U_2(ap->op), GET_BE_U_2(ap->htype),
 289             GET_BE_U_2(ap->ptype), GET_U_1(ap->halen), GET_U_1(ap->palen));
 290         return;
 291 invalid:
 292         nd_print_invalid(ndo);
 293 }
 294
 295 /*
 296  * Print AppleTalk Datagram Delivery Protocol packets.
 297  */
 298 static void
 299 ddp_print(netdissect_options *ndo,
 300           const u_char *bp, u_int length, u_int t,
 301           u_short snet, u_char snode, u_char skt)
 302 {
 303
 304         switch (t) {
 305
 306         case ddpNBP:
 307                 nbp_print(ndo, (const struct atNBP *)bp, length, snet, snode, skt);
 308                 break;
 309
 310         case ddpATP:
 311                 atp_print(ndo, (const struct atATP *)bp, length);
 312                 break;
 313
 314         case ddpEIGRP:
 315                 eigrp_print(ndo, bp, length);
 316                 break;
 317
 318         default:
 319                 ND_PRINT(" at-%s %u", tok2str(type2str, NULL, t), length);
 320                 break;
 321         }
 322 }
 323
 324 static void
 325 atp_print(netdissect_options *ndo,
 326           const struct atATP *ap, u_int length)
 327 {
 328         uint8_t control;
 329         uint32_t data;
 330
 331         ndo->ndo_protocol = "atp";
 332         ND_ICHECKMSG_ZU("ATP length", length, <, sizeof(*ap));
 333         length -= sizeof(*ap);
 334         control = GET_U_1(ap->control);
 335         switch (control & 0xc0) {
 336
 337         case atpReqCode:
 338                 ND_PRINT(" atp-req%s %u",
 339                              control & atpXO? " " : "*",
 340                              GET_BE_U_2(ap->transID));
 341
 342                 atp_bitmap_print(ndo, GET_U_1(ap->bitmap));
 343
 344                 if (length != 0)
 345                         ND_PRINT(" [len=%u]", length);
 346
 347                 switch (control & (atpEOM|atpSTS)) {
 348                 case atpEOM:
 349                         ND_PRINT(" [EOM]");
 350                         break;
 351                 case atpSTS:
 352                         ND_PRINT(" [STS]");
 353                         break;
 354                 case atpEOM|atpSTS:
 355                         ND_PRINT(" [EOM,STS]");
 356                         break;
 357                 }
 358                 break;
 359
 360         case atpRspCode:
 361                 ND_PRINT(" atp-resp%s%u:%u (%u)",
 362                              control & atpEOM? "*" : " ",
 363                              GET_BE_U_2(ap->transID), GET_U_1(ap->bitmap),
 364                              length);
 365                 switch (control & (atpXO|atpSTS)) {
 366                 case atpXO:
 367                         ND_PRINT(" [XO]");
 368                         break;
 369                 case atpSTS:
 370                         ND_PRINT(" [STS]");
 371                         break;
 372                 case atpXO|atpSTS:
 373                         ND_PRINT(" [XO,STS]");
 374                         break;
 375                 }
 376                 break;
 377
 378         case atpRelCode:
 379                 ND_PRINT(" atp-rel  %u", GET_BE_U_2(ap->transID));
 380
 381                 atp_bitmap_print(ndo, GET_U_1(ap->bitmap));
 382
 383                 /* length should be zero */
 384                 if (length)
 385                         ND_PRINT(" [len=%u]", length);
 386
 387                 /* there shouldn't be any control flags */
 388                 if (control & (atpXO|atpEOM|atpSTS)) {
 389                         char c = '[';
 390                         if (control & atpXO) {
 391                                 ND_PRINT("%cXO", c);
 392                                 c = ',';
 393                         }
 394                         if (control & atpEOM) {
 395                                 ND_PRINT("%cEOM", c);
 396                                 c = ',';
 397                         }
 398                         if (control & atpSTS) {
 399                                 ND_PRINT("%cSTS", c);
 400                         }
 401                         ND_PRINT("]");
 402                 }
 403                 break;
 404
 405         default:
 406                 ND_PRINT(" atp-0x%x  %u (%u)", control,
 407                              GET_BE_U_2(ap->transID), length);
 408                 break;
 409         }
 410         data = GET_BE_U_4(ap->userData);
 411         if (data != 0)
 412                 ND_PRINT(" 0x%x", data);
 413         return;
 414 invalid:
 415         nd_print_invalid(ndo);
 416 }
 417
 418 static void
 419 atp_bitmap_print(netdissect_options *ndo,
 420                  u_char bm)
 421 {
 422         u_int i;
 423
 424         /*
 425          * The '& 0xff' below is needed for compilers that want to sign
 426          * extend a u_char, which is the case with the Ultrix compiler.
 427          * (gcc is smart enough to eliminate it, at least on the Sparc).
 428          *
 429          * FIXME: If this problem no longer exists, this workaround should be
 430          * removed.  Otherwise the problem should be consistently detected and
 431          * handled, perhaps at build time.
 432          */
 433         if ((bm + 1) & (bm & 0xff)) {
 434                 char c = '<';
 435                 for (i = 0; bm; ++i) {
 436                         if (bm & 1) {
 437                                 ND_PRINT("%c%u", c, i);
 438                                 c = ',';
 439                         }
 440                         bm >>= 1;
 441                 }
 442                 ND_PRINT(">");
 443         } else {
 444                 for (i = 0; bm; ++i)
 445                         bm >>= 1;
 446                 if (i > 1)
 447                         ND_PRINT("<0-%u>", i - 1);
 448                 else
 449                         ND_PRINT("<0>");
 450         }
 451 }
 452
 453 static void
 454 nbp_print(netdissect_options *ndo,
 455           const struct atNBP *np, u_int length, u_short snet,
 456           u_char snode, u_char skt)
 457 {
 458         const struct atNBPtuple *tp =
 459                 (const struct atNBPtuple *)((const u_char *)np + nbpHeaderSize);
 460         uint8_t control;
 461         u_int i;
 462
 463         /* must be room for at least one tuple */
 464         ND_ICHECKMSG_U("undersized-nbp", length, <, nbpHeaderSize + 8);
 465         length -= nbpHeaderSize;
 466         control = GET_U_1(np->control);
 467         ND_PRINT(" nbp-%s", tok2str(nbp_str, "0x%x", control & 0xf0));
 468         ND_PRINT(" %u", GET_U_1(np->id));
 469         switch (control & 0xf0) {
 470
 471         case nbpBrRq:
 472         case nbpLkUp:
 473                 ND_PRINT(":");
 474                 (void)nbp_name_print(ndo, tp);
 475                 /*
 476                  * look for anomalies: the spec says there can only
 477                  * be one tuple, the address must match the source
 478                  * address and the enumerator should be zero.
 479                  */
 480                 if ((control & 0xf) != 1)
 481                         ND_PRINT(" [ntup=%u]", control & 0xf);
 482                 if (GET_U_1(tp->enumerator))
 483                         ND_PRINT(" [enum=%u]", GET_U_1(tp->enumerator));
 484                 if (GET_BE_U_2(tp->net) != snet ||
 485                     GET_U_1(tp->node) != snode ||
 486                     GET_U_1(tp->skt) != skt)
 487                         ND_PRINT(" [addr=%s.%u]",
 488                             ataddr_string(ndo, GET_BE_U_2(tp->net),
 489                                           GET_U_1(tp->node)),
 490                             GET_U_1(tp->skt));
 491                 break;
 492
 493         case nbpLkUpReply:
 494                 ND_PRINT(":");
 495
 496                 /* print each of the tuples in the reply */
 497                 for (i = control & 0xf; i != 0 && tp; i--)
 498                         tp = nbp_tuple_print(ndo, tp, snet, snode, skt);
 499                 break;
 500
 501         default:
 502                 ND_PRINT("  (%u)", length);
 503                 break;
 504         }
 505         return;
 506 invalid:
 507         nd_print_invalid(ndo);
 508 }
 509
 510 /* print a counted string */
 511 static const u_char *
 512 print_cstring(netdissect_options *ndo,
 513               const u_char *cp)
 514 {
 515         u_int length;
 516
 517         length = GET_U_1(cp);
 518         cp++;
 519
 520         /* Spec says string can be at most 32 bytes long */
 521         if (length > 32) {
 522                 ND_PRINT("[len=%u]", length);
 523                 ND_TCHECK_LEN(cp, length);
 524                 return NULL;
 525         }
 526         nd_printjn(ndo, cp, length);
 527         return cp + length;
 528 }
 529
 530 static const struct atNBPtuple *
 531 nbp_tuple_print(netdissect_options *ndo,
 532                 const struct atNBPtuple *tp,
 533                 u_short snet, u_char snode, u_char skt)
 534 {
 535         const struct atNBPtuple *tpn;
 536
 537         tpn = nbp_name_print(ndo, tp);
 538
 539         /* if the enumerator isn't 1, print it */
 540         if (GET_U_1(tp->enumerator) != 1)
 541                 ND_PRINT("(%u)", GET_U_1(tp->enumerator));
 542
 543         /* if the socket doesn't match the src socket, print it */
 544         if (GET_U_1(tp->skt) != skt)
 545                 ND_PRINT(" %u", GET_U_1(tp->skt));
 546
 547         /* if the address doesn't match the src address, it's an anomaly */
 548         if (GET_BE_U_2(tp->net) != snet ||
 549             GET_U_1(tp->node) != snode)
 550                 ND_PRINT(" [addr=%s]",
 551                     ataddr_string(ndo, GET_BE_U_2(tp->net), GET_U_1(tp->node)));
 552
 553         return (tpn);
 554 }
 555
 556 static const struct atNBPtuple *
 557 nbp_name_print(netdissect_options *ndo,
 558                const struct atNBPtuple *tp)
 559 {
 560         const u_char *cp = (const u_char *)tp + nbpTupleSize;
 561
 562         ND_PRINT(" ");
 563
 564         /* Object */
 565         ND_PRINT("\"");
 566         if ((cp = print_cstring(ndo, cp)) != NULL) {
 567                 /* Type */
 568                 ND_PRINT(":");
 569                 if ((cp = print_cstring(ndo, cp)) != NULL) {
 570                         /* Zone */
 571                         ND_PRINT("@");
 572                         if ((cp = print_cstring(ndo, cp)) != NULL)
 573                                 ND_PRINT("\"");
 574                 }
 575         }
 576         return ((const struct atNBPtuple *)cp);
 577 }
 578
 579
 580 #define HASHNAMESIZE 4096
 581
 582 struct hnamemem {
 583         u_int addr;
 584         char *name;
 585         struct hnamemem *nxt;
 586 };
 587
 588 static struct hnamemem hnametable[HASHNAMESIZE];
 589
 590 static const char *
 591 ataddr_string(netdissect_options *ndo,
 592               u_short atnet, u_char athost)
 593 {
 594         struct hnamemem *tp, *tp2;
 595         u_int i = (atnet << 8) | athost;
 596         char nambuf[256+1];
 597         static int first = 1;
 598         FILE *fp;
 599
 600         /*
 601          * Are we doing address to name resolution?
 602          */
 603         if (!ndo->ndo_nflag) {
 604                 /*
 605                  * Yes.  Have we tried to open and read an AppleTalk
 606                  * number to name map file?
 607                  */
 608                 if (!first) {
 609                         /*
 610                          * No; try to do so.
 611                          */
 612                         first = 0;
 613                         fp = fopen("/etc/atalk.names", "r");
 614                         if (fp != NULL) {
 615                                 char line[256];
 616                                 u_int i1, i2;
 617
 618                                 while (fgets(line, sizeof(line), fp)) {
 619                                         if (line[0] == '\n' || line[0] == 0 ||
 620                                             line[0] == '#')
 621                                                 continue;
 622                                         if (sscanf(line, "%u.%u %256s", &i1,
 623                                             &i2, nambuf) == 3)
 624                                                 /* got a hostname. */
 625                                                 i2 |= (i1 << 8);
 626                                         else if (sscanf(line, "%u %256s", &i1,
 627                                             nambuf) == 2)
 628                                                 /* got a net name */
 629                                                 i2 = (i1 << 8) | 255;
 630                                         else
 631                                                 continue;
 632
 633                                         for (tp = &hnametable[i2 & (HASHNAMESIZE-1)];
 634                                              tp->nxt; tp = tp->nxt)
 635                                                 ;
 636                                         tp->addr = i2;
 637                                         tp->nxt = newhnamemem(ndo);
 638                                         tp->name = strdup(nambuf);
 639                                         if (tp->name == NULL)
 640                                                 (*ndo->ndo_error)(ndo,
 641                                                     S_ERR_ND_MEM_ALLOC,
 642                                                     "%s: strdup(nambuf)", __func__);
 643                                 }
 644                                 fclose(fp);
 645                         }
 646                 }
 647         }
 648
 649         /*
 650          * Now try to look up the address in the table.
 651          */
 652         for (tp = &hnametable[i & (HASHNAMESIZE-1)]; tp->nxt; tp = tp->nxt)
 653                 if (tp->addr == i)
 654                         return (tp->name);
 655
 656         /* didn't have the node name -- see if we've got the net name */
 657         i |= 255;
 658         for (tp2 = &hnametable[i & (HASHNAMESIZE-1)]; tp2->nxt; tp2 = tp2->nxt)
 659                 if (tp2->addr == i) {
 660                         tp->addr = (atnet << 8) | athost;
 661                         tp->nxt = newhnamemem(ndo);
 662                         (void)snprintf(nambuf, sizeof(nambuf), "%s.%u",
 663                             tp2->name, athost);
 664                         tp->name = strdup(nambuf);
 665                         if (tp->name == NULL)
 666                                 (*ndo->ndo_error)(ndo, S_ERR_ND_MEM_ALLOC,
 667                                         "%s: strdup(nambuf)", __func__);
 668                         return (tp->name);
 669                 }
 670
 671         tp->addr = (atnet << 8) | athost;
 672         tp->nxt = newhnamemem(ndo);
 673         if (athost != 255)
 674                 (void)snprintf(nambuf, sizeof(nambuf), "%u.%u", atnet, athost);
 675         else
 676                 (void)snprintf(nambuf, sizeof(nambuf), "%u", atnet);
 677         tp->name = strdup(nambuf);
 678         if (tp->name == NULL)
 679                 (*ndo->ndo_error)(ndo, S_ERR_ND_MEM_ALLOC,
 680                                   "%s: strdup(nambuf)", __func__);
 681
 682         return (tp->name);
 683 }
 684
 685 #define rtmpSkt 1
 686 #define nbpSkt  2
 687 #define echoSkt 4
 688 #define zipSkt  6
 689 static const struct tok skt2str[] = {
 690         { rtmpSkt,      "rtmp" },       /* routing table maintenance */
 691         { nbpSkt,       "nis" },        /* name info socket */
 692         { echoSkt,      "echo" },       /* AppleTalk echo protocol */
 693         { zipSkt,       "zip" },        /* zone info protocol */
 694         { 0,            NULL }
 695 };
 696
 697 static const char *
 698 ddpskt_string(netdissect_options *ndo,
 699               u_int skt)
 700 {
 701         static char buf[8];
 702
 703         if (ndo->ndo_nflag) {
 704                 (void)snprintf(buf, sizeof(buf), "%u", skt);
 705                 return (buf);
 706         }
 707         return (tok2str(skt2str, "%u", skt));
 708 }