The Tcpdump Group git mirrors - tcpdump/blob - print-ip.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: IP printer */
  23
  24 #ifdef HAVE_CONFIG_H
  25 #include "config.h"
  26 #endif
  27
  28 #include <netdissect-stdinc.h>
  29
  30 #include <string.h>
  31
  32 #include "netdissect.h"
  33 #include "addrtoname.h"
  34 #include "extract.h"
  35
  36 #include "ip.h"
  37 #include "ipproto.h"
  38
  39 static const char tstr[] = "[|ip]";
  40
  41 static const struct tok ip_option_values[] = {
  42     { IPOPT_EOL, "EOL" },
  43     { IPOPT_NOP, "NOP" },
  44     { IPOPT_TS, "timestamp" },
  45     { IPOPT_SECURITY, "security" },
  46     { IPOPT_RR, "RR" },
  47     { IPOPT_SSRR, "SSRR" },
  48     { IPOPT_LSRR, "LSRR" },
  49     { IPOPT_RA, "RA" },
  50     { IPOPT_RFC1393, "traceroute" },
  51     { 0, NULL }
  52 };
  53
  54 /*
  55  * print the recorded route in an IP RR, LSRR or SSRR option.
  56  */
  57 static int
  58 ip_printroute(netdissect_options *ndo,
  59               register const u_char *cp, u_int length)
  60 {
  61         register u_int ptr;
  62         register u_int len;
  63
  64         if (length < 3) {
  65                 ND_PRINT((ndo, " [bad length %u]", length));
  66                 return (0);
  67         }
  68         if ((length + 1) & 3)
  69                 ND_PRINT((ndo, " [bad length %u]", length));
  70         ND_TCHECK_1(cp + 2);
  71         ptr = EXTRACT_U_1(cp + 2) - 1;
  72         if (ptr < 3 || ((ptr + 1) & 3) || ptr > length + 1)
  73                 ND_PRINT((ndo, " [bad ptr %u]", EXTRACT_U_1(cp + 2)));
  74
  75         for (len = 3; len < length; len += 4) {
  76                 ND_TCHECK_4(cp + len);
  77                 ND_PRINT((ndo, " %s", ipaddr_string(ndo, cp + len)));
  78                 if (ptr > len)
  79                         ND_PRINT((ndo, ","));
  80         }
  81         return (0);
  82
  83 trunc:
  84         return (-1);
  85 }
  86
  87 /*
  88  * If source-routing is present and valid, return the final destination.
  89  * Otherwise, return IP destination.
  90  *
  91  * This is used for UDP and TCP pseudo-header in the checksum
  92  * calculation.
  93  */
  94 static uint32_t
  95 ip_finddst(netdissect_options *ndo,
  96            const struct ip *ip)
  97 {
  98         int length;
  99         int len;
 100         const u_char *cp;
 101         uint32_t retval;
 102
 103         cp = (const u_char *)(ip + 1);
 104         length = (IP_HL(ip) << 2) - sizeof(struct ip);
 105
 106         for (; length > 0; cp += len, length -= len) {
 107                 int tt;
 108
 109                 ND_TCHECK_1(cp);
 110                 tt = EXTRACT_U_1(cp);
 111                 if (tt == IPOPT_EOL)
 112                         break;
 113                 else if (tt == IPOPT_NOP)
 114                         len = 1;
 115                 else {
 116                         ND_TCHECK_1(cp + 1);
 117                         len = EXTRACT_U_1(cp + 1);
 118                         if (len < 2)
 119                                 break;
 120                 }
 121                 ND_TCHECK2(*cp, len);
 122                 switch (tt) {
 123
 124                 case IPOPT_SSRR:
 125                 case IPOPT_LSRR:
 126                         if (len < 7)
 127                                 break;
 128                         UNALIGNED_MEMCPY(&retval, cp + len - 4, 4);
 129                         return retval;
 130                 }
 131         }
 132 trunc:
 133         UNALIGNED_MEMCPY(&retval, &ip->ip_dst, sizeof(uint32_t));
 134         return retval;
 135 }
 136
 137 /*
 138  * Compute a V4-style checksum by building a pseudoheader.
 139  */
 140 int
 141 nextproto4_cksum(netdissect_options *ndo,
 142                  const struct ip *ip, const uint8_t *data,
 143                  u_int len, u_int covlen, u_int next_proto)
 144 {
 145         struct phdr {
 146                 uint32_t src;
 147                 uint32_t dst;
 148                 u_char mbz;
 149                 u_char proto;
 150                 uint16_t len;
 151         } ph;
 152         struct cksum_vec vec[2];
 153
 154         /* pseudo-header.. */
 155         ph.len = htons((uint16_t)len);
 156         ph.mbz = 0;
 157         ph.proto = next_proto;
 158         UNALIGNED_MEMCPY(&ph.src, &ip->ip_src, sizeof(uint32_t));
 159         if (IP_HL(ip) == 5)
 160                 UNALIGNED_MEMCPY(&ph.dst, &ip->ip_dst, sizeof(uint32_t));
 161         else
 162                 ph.dst = ip_finddst(ndo, ip);
 163
 164         vec[0].ptr = (const uint8_t *)(void *)&ph;
 165         vec[0].len = sizeof(ph);
 166         vec[1].ptr = data;
 167         vec[1].len = covlen;
 168         return (in_cksum(vec, 2));
 169 }
 170
 171 static int
 172 ip_printts(netdissect_options *ndo,
 173            register const u_char *cp, u_int length)
 174 {
 175         register u_int ptr;
 176         register u_int len;
 177         int hoplen;
 178         const char *type;
 179
 180         if (length < 4) {
 181                 ND_PRINT((ndo, "[bad length %u]", length));
 182                 return (0);
 183         }
 184         ND_PRINT((ndo, " TS{"));
 185         ND_TCHECK_1(cp + 3);
 186         hoplen = ((EXTRACT_U_1(cp + 3) & 0xF) != IPOPT_TS_TSONLY) ? 8 : 4;
 187         if ((length - 4) & (hoplen-1))
 188                 ND_PRINT((ndo, "[bad length %u]", length));
 189         ND_TCHECK_1(cp + 2);
 190         ptr = EXTRACT_U_1(cp + 2) - 1;
 191         len = 0;
 192         if (ptr < 4 || ((ptr - 4) & (hoplen-1)) || ptr > length + 1)
 193                 ND_PRINT((ndo, "[bad ptr %u]", EXTRACT_U_1(cp + 2)));
 194         ND_TCHECK_1(cp + 3);
 195         switch (EXTRACT_U_1(cp + 3)&0xF) {
 196         case IPOPT_TS_TSONLY:
 197                 ND_PRINT((ndo, "TSONLY"));
 198                 break;
 199         case IPOPT_TS_TSANDADDR:
 200                 ND_PRINT((ndo, "TS+ADDR"));
 201                 break;
 202         /*
 203          * prespecified should really be 3, but some ones might send 2
 204          * instead, and the IPOPT_TS_PRESPEC constant can apparently
 205          * have both values, so we have to hard-code it here.
 206          */
 207
 208         case 2:
 209                 ND_PRINT((ndo, "PRESPEC2.0"));
 210                 break;
 211         case 3:                 /* IPOPT_TS_PRESPEC */
 212                 ND_PRINT((ndo, "PRESPEC"));
 213                 break;
 214         default:
 215                 ND_PRINT((ndo, "[bad ts type %d]", EXTRACT_U_1(cp + 3)&0xF));
 216                 goto done;
 217         }
 218
 219         type = " ";
 220         for (len = 4; len < length; len += hoplen) {
 221                 if (ptr == len)
 222                         type = " ^ ";
 223                 ND_TCHECK2(cp[len], hoplen);
 224                 ND_PRINT((ndo, "%s%d@%s", type, EXTRACT_BE_U_4(cp + len + hoplen - 4),
 225                           hoplen!=8 ? "" : ipaddr_string(ndo, cp + len)));
 226                 type = " ";
 227         }
 228
 229 done:
 230         ND_PRINT((ndo, "%s", ptr == len ? " ^ " : ""));
 231
 232         if (EXTRACT_U_1(cp + 3) >> 4)
 233                 ND_PRINT((ndo, " [%d hops not recorded]} ", EXTRACT_U_1(cp + 3)>>4));
 234         else
 235                 ND_PRINT((ndo, "}"));
 236         return (0);
 237
 238 trunc:
 239         return (-1);
 240 }
 241
 242 /*
 243  * print IP options.
 244  */
 245 static void
 246 ip_optprint(netdissect_options *ndo,
 247             register const u_char *cp, u_int length)
 248 {
 249         register u_int option_len;
 250         const char *sep = "";
 251
 252         for (; length > 0; cp += option_len, length -= option_len) {
 253                 u_int option_code;
 254
 255                 ND_PRINT((ndo, "%s", sep));
 256                 sep = ",";
 257
 258                 ND_TCHECK_1(cp);
 259                 option_code = EXTRACT_U_1(cp);
 260
 261                 ND_PRINT((ndo, "%s",
 262                           tok2str(ip_option_values,"unknown %u",option_code)));
 263
 264                 if (option_code == IPOPT_NOP ||
 265                     option_code == IPOPT_EOL)
 266                         option_len = 1;
 267
 268                 else {
 269                         ND_TCHECK_1(cp + 1);
 270                         option_len = EXTRACT_U_1(cp + 1);
 271                         if (option_len < 2) {
 272                                 ND_PRINT((ndo, " [bad length %u]", option_len));
 273                                 return;
 274                         }
 275                 }
 276
 277                 if (option_len > length) {
 278                         ND_PRINT((ndo, " [bad length %u]", option_len));
 279                         return;
 280                 }
 281
 282                 ND_TCHECK2(*cp, option_len);
 283
 284                 switch (option_code) {
 285                 case IPOPT_EOL:
 286                         return;
 287
 288                 case IPOPT_TS:
 289                         if (ip_printts(ndo, cp, option_len) == -1)
 290                                 goto trunc;
 291                         break;
 292
 293                 case IPOPT_RR:       /* fall through */
 294                 case IPOPT_SSRR:
 295                 case IPOPT_LSRR:
 296                         if (ip_printroute(ndo, cp, option_len) == -1)
 297                                 goto trunc;
 298                         break;
 299
 300                 case IPOPT_RA:
 301                         if (option_len < 4) {
 302                                 ND_PRINT((ndo, " [bad length %u]", option_len));
 303                                 break;
 304                         }
 305                         ND_TCHECK_1(cp + 3);
 306                         if (EXTRACT_BE_U_2(cp + 2) != 0)
 307                                 ND_PRINT((ndo, " value %u", EXTRACT_BE_U_2(cp + 2)));
 308                         break;
 309
 310                 case IPOPT_NOP:       /* nothing to print - fall through */
 311                 case IPOPT_SECURITY:
 312                 default:
 313                         break;
 314                 }
 315         }
 316         return;
 317
 318 trunc:
 319         ND_PRINT((ndo, "%s", tstr));
 320 }
 321
 322 #define IP_RES 0x8000
 323
 324 static const struct tok ip_frag_values[] = {
 325         { IP_MF,        "+" },
 326         { IP_DF,        "DF" },
 327         { IP_RES,       "rsvd" }, /* The RFC3514 evil ;-) bit */
 328         { 0,            NULL }
 329 };
 330
 331 struct ip_print_demux_state {
 332         const struct ip *ip;
 333         const u_char *cp;
 334         u_int   len, off;
 335         u_char  nh;
 336         int     advance;
 337 };
 338
 339 static void
 340 ip_print_demux(netdissect_options *ndo,
 341                struct ip_print_demux_state *ipds)
 342 {
 343         const char *p_name;
 344
 345 again:
 346         switch (ipds->nh) {
 347
 348         case IPPROTO_AH:
 349                 if (!ND_TTEST(*ipds->cp)) {
 350                         ND_PRINT((ndo, "[|AH]"));
 351                         break;
 352                 }
 353                 ipds->nh = EXTRACT_U_1(ipds->cp);
 354                 ipds->advance = ah_print(ndo, ipds->cp);
 355                 if (ipds->advance <= 0)
 356                         break;
 357                 ipds->cp += ipds->advance;
 358                 ipds->len -= ipds->advance;
 359                 goto again;
 360
 361         case IPPROTO_ESP:
 362         {
 363                 u_int enh, padlen;
 364                 ipds->advance = esp_print(ndo, ipds->cp, ipds->len,
 365                                     (const u_char *)ipds->ip,
 366                                     &enh, &padlen);
 367                 if (ipds->advance <= 0)
 368                         break;
 369                 ipds->cp += ipds->advance;
 370                 ipds->len -= ipds->advance + padlen;
 371                 ipds->nh = enh & 0xff;
 372                 goto again;
 373         }
 374
 375         case IPPROTO_IPCOMP:
 376         {
 377                 ipcomp_print(ndo, ipds->cp);
 378                 /*
 379                  * Either this has decompressed the payload and
 380                  * printed it, in which case there's nothing more
 381                  * to do, or it hasn't, in which case there's
 382                  * nothing more to do.
 383                  */
 384                 break;
 385         }
 386
 387         case IPPROTO_SCTP:
 388                 sctp_print(ndo, ipds->cp, (const u_char *)ipds->ip, ipds->len);
 389                 break;
 390
 391         case IPPROTO_DCCP:
 392                 dccp_print(ndo, ipds->cp, (const u_char *)ipds->ip, ipds->len);
 393                 break;
 394
 395         case IPPROTO_TCP:
 396                 /* pass on the MF bit plus the offset to detect fragments */
 397                 tcp_print(ndo, ipds->cp, ipds->len, (const u_char *)ipds->ip,
 398                           ipds->off & (IP_MF|IP_OFFMASK));
 399                 break;
 400
 401         case IPPROTO_UDP:
 402                 /* pass on the MF bit plus the offset to detect fragments */
 403                 udp_print(ndo, ipds->cp, ipds->len, (const u_char *)ipds->ip,
 404                           ipds->off & (IP_MF|IP_OFFMASK));
 405                 break;
 406
 407         case IPPROTO_ICMP:
 408                 /* pass on the MF bit plus the offset to detect fragments */
 409                 icmp_print(ndo, ipds->cp, ipds->len, (const u_char *)ipds->ip,
 410                            ipds->off & (IP_MF|IP_OFFMASK));
 411                 break;
 412
 413         case IPPROTO_PIGP:
 414                 /*
 415                  * XXX - the current IANA protocol number assignments
 416                  * page lists 9 as "any private interior gateway
 417                  * (used by Cisco for their IGRP)" and 88 as
 418                  * "EIGRP" from Cisco.
 419                  *
 420                  * Recent BSD <netinet/in.h> headers define
 421                  * IP_PROTO_PIGP as 9 and IP_PROTO_IGRP as 88.
 422                  * We define IP_PROTO_PIGP as 9 and
 423                  * IP_PROTO_EIGRP as 88; those names better
 424                  * match was the current protocol number
 425                  * assignments say.
 426                  */
 427                 igrp_print(ndo, ipds->cp, ipds->len);
 428                 break;
 429
 430         case IPPROTO_EIGRP:
 431                 eigrp_print(ndo, ipds->cp, ipds->len);
 432                 break;
 433
 434         case IPPROTO_ND:
 435                 ND_PRINT((ndo, " nd %d", ipds->len));
 436                 break;
 437
 438         case IPPROTO_EGP:
 439                 egp_print(ndo, ipds->cp, ipds->len);
 440                 break;
 441
 442         case IPPROTO_OSPF:
 443                 ospf_print(ndo, ipds->cp, ipds->len, (const u_char *)ipds->ip);
 444                 break;
 445
 446         case IPPROTO_IGMP:
 447                 igmp_print(ndo, ipds->cp, ipds->len);
 448                 break;
 449
 450         case IPPROTO_IPV4:
 451                 /* DVMRP multicast tunnel (ip-in-ip encapsulation) */
 452                 ip_print(ndo, ipds->cp, ipds->len);
 453                 if (! ndo->ndo_vflag) {
 454                         ND_PRINT((ndo, " (ipip-proto-4)"));
 455                         return;
 456                 }
 457                 break;
 458
 459         case IPPROTO_IPV6:
 460                 /* ip6-in-ip encapsulation */
 461                 ip6_print(ndo, ipds->cp, ipds->len);
 462                 break;
 463
 464         case IPPROTO_RSVP:
 465                 rsvp_print(ndo, ipds->cp, ipds->len);
 466                 break;
 467
 468         case IPPROTO_GRE:
 469                 /* do it */
 470                 gre_print(ndo, ipds->cp, ipds->len);
 471                 break;
 472
 473         case IPPROTO_MOBILE:
 474                 mobile_print(ndo, ipds->cp, ipds->len);
 475                 break;
 476
 477         case IPPROTO_PIM:
 478                 pim_print(ndo, ipds->cp, ipds->len, (const u_char *)ipds->ip);
 479                 break;
 480
 481         case IPPROTO_VRRP:
 482                 if (ndo->ndo_packettype == PT_CARP) {
 483                         if (ndo->ndo_vflag)
 484                                 ND_PRINT((ndo, "carp %s > %s: ",
 485                                              ipaddr_string(ndo, &ipds->ip->ip_src),
 486                                              ipaddr_string(ndo, &ipds->ip->ip_dst)));
 487                         carp_print(ndo, ipds->cp, ipds->len,
 488                                 EXTRACT_U_1(ipds->ip->ip_ttl));
 489                 } else {
 490                         if (ndo->ndo_vflag)
 491                                 ND_PRINT((ndo, "vrrp %s > %s: ",
 492                                              ipaddr_string(ndo, &ipds->ip->ip_src),
 493                                              ipaddr_string(ndo, &ipds->ip->ip_dst)));
 494                         vrrp_print(ndo, ipds->cp, ipds->len,
 495                                 (const u_char *)ipds->ip,
 496                                 EXTRACT_U_1(ipds->ip->ip_ttl));
 497                 }
 498                 break;
 499
 500         case IPPROTO_PGM:
 501                 pgm_print(ndo, ipds->cp, ipds->len, (const u_char *)ipds->ip);
 502                 break;
 503
 504         default:
 505                 if (ndo->ndo_nflag==0 && (p_name = netdb_protoname(ipds->nh)) != NULL)
 506                         ND_PRINT((ndo, " %s", p_name));
 507                 else
 508                         ND_PRINT((ndo, " ip-proto-%d", ipds->nh));
 509                 ND_PRINT((ndo, " %d", ipds->len));
 510                 break;
 511         }
 512 }
 513
 514 void
 515 ip_print_inner(netdissect_options *ndo,
 516                const u_char *bp,
 517                u_int length, u_int nh,
 518                const u_char *bp2)
 519 {
 520         struct ip_print_demux_state  ipd;
 521
 522         ipd.ip = (const struct ip *)bp2;
 523         ipd.cp = bp;
 524         ipd.len  = length;
 525         ipd.off  = 0;
 526         ipd.nh   = nh;
 527         ipd.advance = 0;
 528
 529         ip_print_demux(ndo, &ipd);
 530 }
 531
 532
 533 /*
 534  * print an IP datagram.
 535  */
 536 void
 537 ip_print(netdissect_options *ndo,
 538          const u_char *bp,
 539          u_int length)
 540 {
 541         struct ip_print_demux_state  ipd;
 542         struct ip_print_demux_state *ipds=&ipd;
 543         const u_char *ipend;
 544         u_int hlen;
 545         struct cksum_vec vec[1];
 546         uint8_t ip_tos, ip_ttl, ip_proto;
 547         uint16_t sum, ip_sum;
 548         const char *p_name;
 549
 550         ipds->ip = (const struct ip *)bp;
 551         ND_TCHECK(ipds->ip->ip_vhl);
 552         if (IP_V(ipds->ip) != 4) { /* print version and fail if != 4 */
 553             if (IP_V(ipds->ip) == 6)
 554               ND_PRINT((ndo, "IP6, wrong link-layer encapsulation "));
 555             else
 556               ND_PRINT((ndo, "IP%u ", IP_V(ipds->ip)));
 557             return;
 558         }
 559         if (!ndo->ndo_eflag)
 560                 ND_PRINT((ndo, "IP "));
 561
 562         ND_TCHECK(*ipds->ip);
 563         if (length < sizeof (struct ip)) {
 564                 ND_PRINT((ndo, "truncated-ip %u", length));
 565                 return;
 566         }
 567         hlen = IP_HL(ipds->ip) * 4;
 568         if (hlen < sizeof (struct ip)) {
 569                 ND_PRINT((ndo, "bad-hlen %u", hlen));
 570                 return;
 571         }
 572
 573         ipds->len = EXTRACT_BE_U_2(&ipds->ip->ip_len);
 574         if (length < ipds->len)
 575                 ND_PRINT((ndo, "truncated-ip - %u bytes missing! ",
 576                         ipds->len - length));
 577         if (ipds->len < hlen) {
 578 #ifdef GUESS_TSO
 579             if (ipds->len) {
 580                 ND_PRINT((ndo, "bad-len %u", ipds->len));
 581                 return;
 582             }
 583             else {
 584                 /* we guess that it is a TSO send */
 585                 ipds->len = length;
 586             }
 587 #else
 588             ND_PRINT((ndo, "bad-len %u", ipds->len));
 589             return;
 590 #endif /* GUESS_TSO */
 591         }
 592
 593         /*
 594          * Cut off the snapshot length to the end of the IP payload.
 595          */
 596         ipend = bp + ipds->len;
 597         if (ipend < ndo->ndo_snapend)
 598                 ndo->ndo_snapend = ipend;
 599
 600         ipds->len -= hlen;
 601
 602         ipds->off = EXTRACT_BE_U_2(&ipds->ip->ip_off);
 603
 604         ip_proto = EXTRACT_U_1(ipds->ip->ip_p);
 605
 606         if (ndo->ndo_vflag) {
 607             ip_tos = EXTRACT_U_1(ipds->ip->ip_tos);
 608             ND_PRINT((ndo, "(tos 0x%x", ip_tos));
 609             /* ECN bits */
 610             switch (ip_tos & 0x03) {
 611
 612             case 0:
 613                 break;
 614
 615             case 1:
 616                 ND_PRINT((ndo, ",ECT(1)"));
 617                 break;
 618
 619             case 2:
 620                 ND_PRINT((ndo, ",ECT(0)"));
 621                 break;
 622
 623             case 3:
 624                 ND_PRINT((ndo, ",CE"));
 625                 break;
 626             }
 627
 628             ip_ttl = EXTRACT_U_1(ipds->ip->ip_ttl);
 629             if (ip_ttl >= 1)
 630                 ND_PRINT((ndo, ", ttl %u", ip_ttl));
 631
 632             /*
 633              * for the firewall guys, print id, offset.
 634              * On all but the last stick a "+" in the flags portion.
 635              * For unfragmented datagrams, note the don't fragment flag.
 636              */
 637             ND_PRINT((ndo, ", id %u, offset %u, flags [%s], proto %s (%u)",
 638                          EXTRACT_BE_U_2(&ipds->ip->ip_id),
 639                          (ipds->off & 0x1fff) * 8,
 640                          bittok2str(ip_frag_values, "none", ipds->off&0xe000),
 641                          tok2str(ipproto_values, "unknown", ip_proto),
 642                          ip_proto));
 643
 644             ND_PRINT((ndo, ", length %u", EXTRACT_BE_U_2(ipds->ip->ip_len)));
 645
 646             if ((hlen - sizeof(struct ip)) > 0) {
 647                 ND_PRINT((ndo, ", options ("));
 648                 ip_optprint(ndo, (const u_char *)(ipds->ip + 1), hlen - sizeof(struct ip));
 649                 ND_PRINT((ndo, ")"));
 650             }
 651
 652             if (!ndo->ndo_Kflag && (const u_char *)ipds->ip + hlen <= ndo->ndo_snapend) {
 653                 vec[0].ptr = (const uint8_t *)(const void *)ipds->ip;
 654                 vec[0].len = hlen;
 655                 sum = in_cksum(vec, 1);
 656                 if (sum != 0) {
 657                     ip_sum = EXTRACT_BE_U_2(ipds->ip->ip_sum);
 658                     ND_PRINT((ndo, ", bad cksum %x (->%x)!", ip_sum,
 659                              in_cksum_shouldbe(ip_sum, sum)));
 660                 }
 661             }
 662
 663             ND_PRINT((ndo, ")\n    "));
 664         }
 665
 666         /*
 667          * If this is fragment zero, hand it to the next higher
 668          * level protocol.
 669          */
 670         if ((ipds->off & 0x1fff) == 0) {
 671                 ipds->cp = (const u_char *)ipds->ip + hlen;
 672                 ipds->nh = EXTRACT_U_1(ipds->ip->ip_p);
 673
 674                 if (ipds->nh != IPPROTO_TCP && ipds->nh != IPPROTO_UDP &&
 675                     ipds->nh != IPPROTO_SCTP && ipds->nh != IPPROTO_DCCP) {
 676                         ND_PRINT((ndo, "%s > %s: ",
 677                                      ipaddr_string(ndo, &ipds->ip->ip_src),
 678                                      ipaddr_string(ndo, &ipds->ip->ip_dst)));
 679                 }
 680                 ip_print_demux(ndo, ipds);
 681         } else {
 682                 /*
 683                  * Ultra quiet now means that all this stuff should be
 684                  * suppressed.
 685                  */
 686                 if (ndo->ndo_qflag > 1)
 687                         return;
 688
 689                 /*
 690                  * This isn't the first frag, so we're missing the
 691                  * next level protocol header.  print the ip addr
 692                  * and the protocol.
 693                  */
 694                 ND_PRINT((ndo, "%s > %s:", ipaddr_string(ndo, &ipds->ip->ip_src),
 695                           ipaddr_string(ndo, &ipds->ip->ip_dst)));
 696                 if (!ndo->ndo_nflag && (p_name = netdb_protoname(ip_proto)) != NULL)
 697                         ND_PRINT((ndo, " %s", p_name));
 698                 else
 699                         ND_PRINT((ndo, " ip-proto-%u", ip_proto));
 700         }
 701         return;
 702
 703 trunc:
 704         ND_PRINT((ndo, "%s", tstr));
 705         return;
 706 }
 707
 708 void
 709 ipN_print(netdissect_options *ndo, register const u_char *bp, register u_int length)
 710 {
 711         if (length < 1) {
 712                 ND_PRINT((ndo, "truncated-ip %d", length));
 713                 return;
 714         }
 715
 716         ND_TCHECK_1(bp);
 717         switch (EXTRACT_U_1(bp) & 0xF0) {
 718         case 0x40:
 719                 ip_print (ndo, bp, length);
 720                 break;
 721         case 0x60:
 722                 ip6_print (ndo, bp, length);
 723                 break;
 724         default:
 725                 ND_PRINT((ndo, "unknown ip %u", (EXTRACT_U_1(bp) & 0xF0) >> 4));
 726                 break;
 727         }
 728         return;
 729
 730 trunc:
 731         ND_PRINT((ndo, "%s", tstr));
 732         return;
 733 }
 734
 735 /*
 736  * Local Variables:
 737  * c-style: whitesmith
 738  * c-basic-offset: 8
 739  * End:
 740  */
 741
 742