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

   1 /*
   2  * Copyright (C) Arnaldo Carvalho de Melo 2004
   3  * Copyright (C) Ian McDonald 2005
   4  * Copyright (C) Yoshifumi Nishida 2005
   5  *
   6  * This software may be distributed either under the terms of the
   7  * BSD-style license that accompanies tcpdump or the GNU GPL version 2
   8  */
   9
  10 #ifdef HAVE_CONFIG_H
  11 #include "config.h"
  12 #endif
  13
  14 #include <netdissect-stdinc.h>
  15
  16 #include <stdio.h>
  17 #include <string.h>
  18
  19 #include "netdissect.h"
  20 #include "addrtoname.h"
  21 #include "extract.h"
  22 #include "ip.h"
  23 #include "ip6.h"
  24 #include "ipproto.h"
  25
  26 /* RFC4340: Datagram Congestion Control Protocol (DCCP) */
  27
  28 /**
  29  * struct dccp_hdr - generic part of DCCP packet header, with a 24-bit
  30  * sequence number
  31  *
  32  * @dccph_sport - Relevant port on the endpoint that sent this packet
  33  * @dccph_dport - Relevant port on the other endpoint
  34  * @dccph_doff - Data Offset from the start of the DCCP header, in 32-bit words
  35  * @dccph_ccval - Used by the HC-Sender CCID
  36  * @dccph_cscov - Parts of the packet that are covered by the Checksum field
  37  * @dccph_checksum - Internet checksum, depends on dccph_cscov
  38  * @dccph_x - 0 = 24 bit sequence number, 1 = 48
  39  * @dccph_type - packet type, see DCCP_PKT_ prefixed macros
  40  * @dccph_seq - 24-bit sequence number
  41  */
  42 struct dccp_hdr {
  43         uint16_t        dccph_sport,
  44                         dccph_dport;
  45         uint8_t         dccph_doff;
  46         uint8_t         dccph_ccval_cscov;
  47         uint16_t        dccph_checksum;
  48         uint8_t         dccph_xtr;
  49         uint8_t         dccph_seq[3];
  50 } UNALIGNED;
  51
  52 /**
  53  * struct dccp_hdr_ext - generic part of DCCP packet header, with a 48-bit
  54  * sequence number
  55  *
  56  * @dccph_sport - Relevant port on the endpoint that sent this packet
  57  * @dccph_dport - Relevant port on the other endpoint
  58  * @dccph_doff - Data Offset from the start of the DCCP header, in 32-bit words
  59  * @dccph_ccval - Used by the HC-Sender CCID
  60  * @dccph_cscov - Parts of the packet that are covered by the Checksum field
  61  * @dccph_checksum - Internet checksum, depends on dccph_cscov
  62  * @dccph_x - 0 = 24 bit sequence number, 1 = 48
  63  * @dccph_type - packet type, see DCCP_PKT_ prefixed macros
  64  * @dccph_seq - 48-bit sequence number
  65  */
  66 struct dccp_hdr_ext {
  67         uint16_t        dccph_sport,
  68                         dccph_dport;
  69         uint8_t         dccph_doff;
  70         uint8_t         dccph_ccval_cscov;
  71         uint16_t        dccph_checksum;
  72         uint8_t         dccph_xtr;
  73         uint8_t         reserved;
  74         uint8_t         dccph_seq[6];
  75 } UNALIGNED;
  76
  77 #define DCCPH_CCVAL(dh) (((dh)->dccph_ccval_cscov >> 4) & 0xF)
  78 #define DCCPH_CSCOV(dh) (((dh)->dccph_ccval_cscov) & 0xF)
  79
  80 #define DCCPH_X(dh)     ((dh)->dccph_xtr & 1)
  81 #define DCCPH_TYPE(dh)  (((dh)->dccph_xtr >> 1) & 0xF)
  82
  83 /**
  84  * struct dccp_hdr_request - Conection initiation request header
  85  *
  86  * @dccph_req_service - Service to which the client app wants to connect
  87  */
  88 struct dccp_hdr_request {
  89         uint32_t        dccph_req_service;
  90 } UNALIGNED;
  91
  92 /**
  93  * struct dccp_hdr_response - Conection initiation response header
  94  *
  95  * @dccph_resp_ack - 48 bit ack number, contains GSR
  96  * @dccph_resp_service - Echoes the Service Code on a received DCCP-Request
  97  */
  98 struct dccp_hdr_response {
  99         uint8_t                         dccph_resp_ack[8];      /* always 8 bytes */
 100         uint32_t                        dccph_resp_service;
 101 } UNALIGNED;
 102
 103 /**
 104  * struct dccp_hdr_reset - Unconditionally shut down a connection
 105  *
 106  * @dccph_resp_ack - 48 bit ack number
 107  * @dccph_reset_service - Echoes the Service Code on a received DCCP-Request
 108  */
 109 struct dccp_hdr_reset {
 110         uint8_t                         dccph_reset_ack[8];     /* always 8 bytes */
 111         uint8_t                         dccph_reset_code,
 112                                         dccph_reset_data[3];
 113 } UNALIGNED;
 114
 115 enum dccp_pkt_type {
 116         DCCP_PKT_REQUEST = 0,
 117         DCCP_PKT_RESPONSE,
 118         DCCP_PKT_DATA,
 119         DCCP_PKT_ACK,
 120         DCCP_PKT_DATAACK,
 121         DCCP_PKT_CLOSEREQ,
 122         DCCP_PKT_CLOSE,
 123         DCCP_PKT_RESET,
 124         DCCP_PKT_SYNC,
 125         DCCP_PKT_SYNCACK
 126 };
 127
 128 static const struct tok dccp_pkt_type_str[] = {
 129         { DCCP_PKT_REQUEST, "DCCP-Request" },
 130         { DCCP_PKT_RESPONSE, "DCCP-Response" },
 131         { DCCP_PKT_DATA, "DCCP-Data" },
 132         { DCCP_PKT_ACK, "DCCP-Ack" },
 133         { DCCP_PKT_DATAACK, "DCCP-DataAck" },
 134         { DCCP_PKT_CLOSEREQ, "DCCP-CloseReq" },
 135         { DCCP_PKT_CLOSE, "DCCP-Close" },
 136         { DCCP_PKT_RESET, "DCCP-Reset" },
 137         { DCCP_PKT_SYNC, "DCCP-Sync" },
 138         { DCCP_PKT_SYNCACK, "DCCP-SyncAck" },
 139         { 0, NULL}
 140 };
 141
 142 enum dccp_reset_codes {
 143         DCCP_RESET_CODE_UNSPECIFIED = 0,
 144         DCCP_RESET_CODE_CLOSED,
 145         DCCP_RESET_CODE_ABORTED,
 146         DCCP_RESET_CODE_NO_CONNECTION,
 147         DCCP_RESET_CODE_PACKET_ERROR,
 148         DCCP_RESET_CODE_OPTION_ERROR,
 149         DCCP_RESET_CODE_MANDATORY_ERROR,
 150         DCCP_RESET_CODE_CONNECTION_REFUSED,
 151         DCCP_RESET_CODE_BAD_SERVICE_CODE,
 152         DCCP_RESET_CODE_TOO_BUSY,
 153         DCCP_RESET_CODE_BAD_INIT_COOKIE,
 154         DCCP_RESET_CODE_AGGRESSION_PENALTY,
 155         __DCCP_RESET_CODE_LAST
 156 };
 157
 158 static const char tstr[] = "[|dccp]";
 159
 160 static const char *dccp_reset_codes[] = {
 161         "unspecified",
 162         "closed",
 163         "aborted",
 164         "no_connection",
 165         "packet_error",
 166         "option_error",
 167         "mandatory_error",
 168         "connection_refused",
 169         "bad_service_code",
 170         "too_busy",
 171         "bad_init_cookie",
 172         "aggression_penalty",
 173 };
 174
 175 static const char *dccp_feature_nums[] = {
 176         "reserved",
 177         "ccid",
 178         "allow_short_seqno",
 179         "sequence_window",
 180         "ecn_incapable",
 181         "ack_ratio",
 182         "send_ack_vector",
 183         "send_ndp_count",
 184         "minimum checksum coverage",
 185         "check data checksum",
 186 };
 187
 188 static inline u_int dccp_csum_coverage(const struct dccp_hdr* dh, u_int len)
 189 {
 190         u_int cov;
 191
 192         if (DCCPH_CSCOV(dh) == 0)
 193                 return len;
 194         cov = (dh->dccph_doff + DCCPH_CSCOV(dh) - 1) * sizeof(uint32_t);
 195         return (cov > len)? len : cov;
 196 }
 197
 198 static int dccp_cksum(netdissect_options *ndo, const struct ip *ip,
 199         const struct dccp_hdr *dh, u_int len)
 200 {
 201         return nextproto4_cksum(ndo, ip, (const uint8_t *)(const void *)dh, len,
 202                                 dccp_csum_coverage(dh, len), IPPROTO_DCCP);
 203 }
 204
 205 static int dccp6_cksum(netdissect_options *ndo, const struct ip6_hdr *ip6,
 206         const struct dccp_hdr *dh, u_int len)
 207 {
 208         return nextproto6_cksum(ndo, ip6, (const uint8_t *)(const void *)dh, len,
 209                                 dccp_csum_coverage(dh, len), IPPROTO_DCCP);
 210 }
 211
 212 static const char *dccp_reset_code(uint8_t code)
 213 {
 214         if (code >= __DCCP_RESET_CODE_LAST)
 215                 return "invalid";
 216         return dccp_reset_codes[code];
 217 }
 218
 219 static uint64_t dccp_seqno(const u_char *bp)
 220 {
 221         const struct dccp_hdr *dh = (const struct dccp_hdr *)bp;
 222         uint64_t seqno;
 223
 224         if (DCCPH_X(dh) != 0) {
 225                 const struct dccp_hdr_ext *dhx = (const struct dccp_hdr_ext *)bp;
 226                 seqno = EXTRACT_48BITS(dhx->dccph_seq);
 227         } else {
 228                 seqno = EXTRACT_24BITS(dh->dccph_seq);
 229         }
 230
 231         return seqno;
 232 }
 233
 234 static inline unsigned int dccp_basic_hdr_len(const struct dccp_hdr *dh)
 235 {
 236         return DCCPH_X(dh) ? sizeof(struct dccp_hdr_ext) : sizeof(struct dccp_hdr);
 237 }
 238
 239 static void dccp_print_ack_no(netdissect_options *ndo, const u_char *bp)
 240 {
 241         const struct dccp_hdr *dh = (const struct dccp_hdr *)bp;
 242         const u_char *ackp = bp + dccp_basic_hdr_len(dh);
 243         uint64_t ackno;
 244
 245         if (DCCPH_X(dh) != 0) {
 246                 ND_TCHECK2(*ackp, 8);
 247                 ackno = EXTRACT_48BITS(ackp + 2);
 248         } else {
 249                 ND_TCHECK2(*ackp, 4);
 250                 ackno = EXTRACT_24BITS(ackp + 1);
 251         }
 252
 253         ND_PRINT((ndo, "(ack=%" PRIu64 ") ", ackno));
 254 trunc:
 255         return;
 256 }
 257
 258 static int dccp_print_option(netdissect_options *, const u_char *, u_int);
 259
 260 /**
 261  * dccp_print - show dccp packet
 262  * @bp - beginning of dccp packet
 263  * @data2 - beginning of enclosing
 264  * @len - lenght of ip packet
 265  */
 266 void dccp_print(netdissect_options *ndo, const u_char *bp, const u_char *data2,
 267                 u_int len)
 268 {
 269         const struct dccp_hdr *dh;
 270         const struct ip *ip;
 271         const struct ip6_hdr *ip6;
 272         const u_char *cp;
 273         u_short sport, dport;
 274         u_int hlen;
 275         u_int fixed_hdrlen;
 276         uint8_t dccph_type;
 277
 278         dh = (const struct dccp_hdr *)bp;
 279
 280         ip = (const struct ip *)data2;
 281         if (IP_V(ip) == 6)
 282                 ip6 = (const struct ip6_hdr *)data2;
 283         else
 284                 ip6 = NULL;
 285
 286         /* make sure we have enough data to look at the X bit */
 287         cp = (const u_char *)(dh + 1);
 288         if (cp > ndo->ndo_snapend) {
 289                 ND_PRINT((ndo, "[Invalid packet|dccp]"));
 290                 return;
 291         }
 292         if (len < sizeof(struct dccp_hdr)) {
 293                 ND_PRINT((ndo, "truncated-dccp - %u bytes missing!",
 294                           len - (u_int)sizeof(struct dccp_hdr)));
 295                 return;
 296         }
 297
 298         /* get the length of the generic header */
 299         fixed_hdrlen = dccp_basic_hdr_len(dh);
 300         if (len < fixed_hdrlen) {
 301                 ND_PRINT((ndo, "truncated-dccp - %u bytes missing!",
 302                           len - fixed_hdrlen));
 303                 return;
 304         }
 305         ND_TCHECK2(*dh, fixed_hdrlen);
 306
 307         sport = EXTRACT_16BITS(&dh->dccph_sport);
 308         dport = EXTRACT_16BITS(&dh->dccph_dport);
 309         hlen = dh->dccph_doff * 4;
 310
 311         if (ip6) {
 312                 ND_PRINT((ndo, "%s.%d > %s.%d: ",
 313                           ip6addr_string(ndo, &ip6->ip6_src), sport,
 314                           ip6addr_string(ndo, &ip6->ip6_dst), dport));
 315         } else {
 316                 ND_PRINT((ndo, "%s.%d > %s.%d: ",
 317                           ipaddr_string(ndo, &ip->ip_src), sport,
 318                           ipaddr_string(ndo, &ip->ip_dst), dport));
 319         }
 320
 321         ND_PRINT((ndo, "DCCP"));
 322
 323         if (ndo->ndo_qflag) {
 324                 ND_PRINT((ndo, " %d", len - hlen));
 325                 if (hlen > len) {
 326                         ND_PRINT((ndo, " [bad hdr length %u - too long, > %u]",
 327                                   hlen, len));
 328                 }
 329                 return;
 330         }
 331
 332         /* other variables in generic header */
 333         if (ndo->ndo_vflag) {
 334                 ND_PRINT((ndo, " (CCVal %d, CsCov %d, ", DCCPH_CCVAL(dh), DCCPH_CSCOV(dh)));
 335         }
 336
 337         /* checksum calculation */
 338         if (ndo->ndo_vflag && ND_TTEST2(bp[0], len)) {
 339                 uint16_t sum = 0, dccp_sum;
 340
 341                 dccp_sum = EXTRACT_16BITS(&dh->dccph_checksum);
 342                 ND_PRINT((ndo, "cksum 0x%04x ", dccp_sum));
 343                 if (IP_V(ip) == 4)
 344                         sum = dccp_cksum(ndo, ip, dh, len);
 345                 else if (IP_V(ip) == 6)
 346                         sum = dccp6_cksum(ndo, ip6, dh, len);
 347                 if (sum != 0)
 348                         ND_PRINT((ndo, "(incorrect -> 0x%04x)",in_cksum_shouldbe(dccp_sum, sum)));
 349                 else
 350                         ND_PRINT((ndo, "(correct)"));
 351         }
 352
 353         if (ndo->ndo_vflag)
 354                 ND_PRINT((ndo, ")"));
 355         ND_PRINT((ndo, " "));
 356
 357         dccph_type = DCCPH_TYPE(dh);
 358         switch (dccph_type) {
 359         case DCCP_PKT_REQUEST: {
 360                 const struct dccp_hdr_request *dhr =
 361                         (const struct dccp_hdr_request *)(bp + fixed_hdrlen);
 362                 fixed_hdrlen += 4;
 363                 if (len < fixed_hdrlen) {
 364                         ND_PRINT((ndo, "truncated-%s - %u bytes missing!",
 365                                   tok2str(dccp_pkt_type_str, "", dccph_type),
 366                                   len - fixed_hdrlen));
 367                         return;
 368                 }
 369                 ND_TCHECK(*dhr);
 370                 ND_PRINT((ndo, "%s (service=%d) ",
 371                           tok2str(dccp_pkt_type_str, "", dccph_type),
 372                           EXTRACT_32BITS(&dhr->dccph_req_service)));
 373                 break;
 374         }
 375         case DCCP_PKT_RESPONSE: {
 376                 const struct dccp_hdr_response *dhr =
 377                         (const struct dccp_hdr_response *)(bp + fixed_hdrlen);
 378                 fixed_hdrlen += 12;
 379                 if (len < fixed_hdrlen) {
 380                         ND_PRINT((ndo, "truncated-%s - %u bytes missing!",
 381                                   tok2str(dccp_pkt_type_str, "", dccph_type),
 382                                   len - fixed_hdrlen));
 383                         return;
 384                 }
 385                 ND_TCHECK(*dhr);
 386                 ND_PRINT((ndo, "%s (service=%d) ",
 387                           tok2str(dccp_pkt_type_str, "", dccph_type),
 388                           EXTRACT_32BITS(&dhr->dccph_resp_service)));
 389                 break;
 390         }
 391         case DCCP_PKT_DATA:
 392                 ND_PRINT((ndo, "%s ", tok2str(dccp_pkt_type_str, "", dccph_type)));
 393                 break;
 394         case DCCP_PKT_ACK: {
 395                 fixed_hdrlen += 8;
 396                 if (len < fixed_hdrlen) {
 397                         ND_PRINT((ndo, "truncated-%s - %u bytes missing!",
 398                                   tok2str(dccp_pkt_type_str, "", dccph_type),
 399                                   len - fixed_hdrlen));
 400                         return;
 401                 }
 402                 ND_PRINT((ndo, "%s ", tok2str(dccp_pkt_type_str, "", dccph_type)));
 403                 break;
 404         }
 405         case DCCP_PKT_DATAACK: {
 406                 fixed_hdrlen += 8;
 407                 if (len < fixed_hdrlen) {
 408                         ND_PRINT((ndo, "truncated-%s - %u bytes missing!",
 409                                   tok2str(dccp_pkt_type_str, "", dccph_type),
 410                                   len - fixed_hdrlen));
 411                         return;
 412                 }
 413                 ND_PRINT((ndo, "%s ", tok2str(dccp_pkt_type_str, "", dccph_type)));
 414                 break;
 415         }
 416         case DCCP_PKT_CLOSEREQ:
 417                 fixed_hdrlen += 8;
 418                 if (len < fixed_hdrlen) {
 419                         ND_PRINT((ndo, "truncated-%s - %u bytes missing!",
 420                                   tok2str(dccp_pkt_type_str, "", dccph_type),
 421                                   len - fixed_hdrlen));
 422                         return;
 423                 }
 424                 ND_PRINT((ndo, "%s ", tok2str(dccp_pkt_type_str, "", dccph_type)));
 425                 break;
 426         case DCCP_PKT_CLOSE:
 427                 fixed_hdrlen += 8;
 428                 if (len < fixed_hdrlen) {
 429                         ND_PRINT((ndo, "truncated-%s - %u bytes missing!",
 430                                   tok2str(dccp_pkt_type_str, "", dccph_type),
 431                                   len - fixed_hdrlen));
 432                         return;
 433                 }
 434                 ND_PRINT((ndo, "%s ", tok2str(dccp_pkt_type_str, "", dccph_type)));
 435                 break;
 436         case DCCP_PKT_RESET: {
 437                 const struct dccp_hdr_reset *dhr =
 438                         (const struct dccp_hdr_reset *)(bp + fixed_hdrlen);
 439                 fixed_hdrlen += 12;
 440                 if (len < fixed_hdrlen) {
 441                         ND_PRINT((ndo, "truncated-%s - %u bytes missing!",
 442                                   tok2str(dccp_pkt_type_str, "", dccph_type),
 443                                   len - fixed_hdrlen));
 444                         return;
 445                 }
 446                 ND_TCHECK(*dhr);
 447                 ND_PRINT((ndo, "%s (code=%s) ",
 448                           tok2str(dccp_pkt_type_str, "", dccph_type),
 449                           dccp_reset_code(dhr->dccph_reset_code)));
 450                 break;
 451         }
 452         case DCCP_PKT_SYNC:
 453                 fixed_hdrlen += 8;
 454                 if (len < fixed_hdrlen) {
 455                         ND_PRINT((ndo, "truncated-%s - %u bytes missing!",
 456                                   tok2str(dccp_pkt_type_str, "", dccph_type),
 457                                   len - fixed_hdrlen));
 458                         return;
 459                 }
 460                 ND_PRINT((ndo, "%s ", tok2str(dccp_pkt_type_str, "", dccph_type)));
 461                 break;
 462         case DCCP_PKT_SYNCACK:
 463                 fixed_hdrlen += 8;
 464                 if (len < fixed_hdrlen) {
 465                         ND_PRINT((ndo, "truncated-%s - %u bytes missing!",
 466                                   tok2str(dccp_pkt_type_str, "", dccph_type),
 467                                   len - fixed_hdrlen));
 468                         return;
 469                 }
 470                 ND_PRINT((ndo, "%s ", tok2str(dccp_pkt_type_str, "", dccph_type)));
 471                 break;
 472         default:
 473                 ND_PRINT((ndo, "%s ", tok2str(dccp_pkt_type_str, "unknown-type-%u", dccph_type)));
 474                 break;
 475         }
 476
 477         if ((DCCPH_TYPE(dh) != DCCP_PKT_DATA) &&
 478                         (DCCPH_TYPE(dh) != DCCP_PKT_REQUEST))
 479                 dccp_print_ack_no(ndo, bp);
 480
 481         if (ndo->ndo_vflag < 2)
 482                 return;
 483
 484         ND_PRINT((ndo, "seq %" PRIu64, dccp_seqno(bp)));
 485
 486         /* process options */
 487         if (hlen > fixed_hdrlen){
 488                 u_int optlen;
 489                 cp = bp + fixed_hdrlen;
 490                 ND_PRINT((ndo, " <"));
 491
 492                 hlen -= fixed_hdrlen;
 493                 while(1){
 494                         optlen = dccp_print_option(ndo, cp, hlen);
 495                         if (!optlen)
 496                                 break;
 497                         if (hlen <= optlen)
 498                                 break;
 499                         hlen -= optlen;
 500                         cp += optlen;
 501                         ND_PRINT((ndo, ", "));
 502                 }
 503                 ND_PRINT((ndo, ">"));
 504         }
 505         return;
 506 trunc:
 507         ND_PRINT((ndo, "%s", tstr));
 508         return;
 509 }
 510
 511 static const struct tok dccp_option_values[] = {
 512         { 0, "nop" },
 513         { 1, "mandatory" },
 514         { 2, "slowreceiver" },
 515         { 32, "change_l" },
 516         { 33, "confirm_l" },
 517         { 34, "change_r" },
 518         { 35, "confirm_r" },
 519         { 36, "initcookie" },
 520         { 37, "ndp_count" },
 521         { 38, "ack_vector0" },
 522         { 39, "ack_vector1" },
 523         { 40, "data_dropped" },
 524         { 41, "timestamp" },
 525         { 42, "timestamp_echo" },
 526         { 43, "elapsed_time" },
 527         { 44, "data_checksum" },
 528         { 0, NULL }
 529 };
 530
 531 static int dccp_print_option(netdissect_options *ndo, const u_char *option, u_int hlen)
 532 {
 533         uint8_t optlen, i;
 534
 535         ND_TCHECK(*option);
 536
 537         if (*option >= 32) {
 538                 ND_TCHECK(*(option+1));
 539                 optlen = *(option +1);
 540                 if (optlen < 2) {
 541                         if (*option >= 128)
 542                                 ND_PRINT((ndo, "CCID option %u optlen too short", *option));
 543                         else
 544                                 ND_PRINT((ndo, "%s optlen too short",
 545                                           tok2str(dccp_option_values, "Option %u", *option)));
 546                         return 0;
 547                 }
 548         } else
 549                 optlen = 1;
 550
 551         if (hlen < optlen) {
 552                 if (*option >= 128)
 553                         ND_PRINT((ndo, "CCID option %u optlen goes past header length",
 554                                   *option));
 555                 else
 556                         ND_PRINT((ndo, "%s optlen goes past header length",
 557                                   tok2str(dccp_option_values, "Option %u", *option)));
 558                 return 0;
 559         }
 560         ND_TCHECK2(*option, optlen);
 561
 562         if (*option >= 128) {
 563                 ND_PRINT((ndo, "CCID option %d", *option));
 564                 switch (optlen) {
 565                         case 4:
 566                                 ND_PRINT((ndo, " %u", EXTRACT_16BITS(option + 2)));
 567                                 break;
 568                         case 6:
 569                                 ND_PRINT((ndo, " %u", EXTRACT_32BITS(option + 2)));
 570                                 break;
 571                         default:
 572                                 break;
 573                 }
 574         } else {
 575                 ND_PRINT((ndo, "%s", tok2str(dccp_option_values, "Option %u", *option)));
 576                 switch (*option) {
 577                 case 32:
 578                 case 33:
 579                 case 34:
 580                 case 35:
 581                         if (optlen < 3) {
 582                                 ND_PRINT((ndo, " optlen too short"));
 583                                 return optlen;
 584                         }
 585                         if (*(option + 2) < 10){
 586                                 ND_PRINT((ndo, " %s", dccp_feature_nums[*(option + 2)]));
 587                                 for (i = 0; i < optlen - 3; i++)
 588                                         ND_PRINT((ndo, " %d", *(option + 3 + i)));
 589                         }
 590                         break;
 591                 case 36:
 592                         if (optlen > 2) {
 593                                 ND_PRINT((ndo, " 0x"));
 594                                 for (i = 0; i < optlen - 2; i++)
 595                                         ND_PRINT((ndo, "%02x", *(option + 2 + i)));
 596                         }
 597                         break;
 598                 case 37:
 599                         for (i = 0; i < optlen - 2; i++)
 600                                 ND_PRINT((ndo, " %d", *(option + 2 + i)));
 601                         break;
 602                 case 38:
 603                         if (optlen > 2) {
 604                                 ND_PRINT((ndo, " 0x"));
 605                                 for (i = 0; i < optlen - 2; i++)
 606                                         ND_PRINT((ndo, "%02x", *(option + 2 + i)));
 607                         }
 608                         break;
 609                 case 39:
 610                         if (optlen > 2) {
 611                                 ND_PRINT((ndo, " 0x"));
 612                                 for (i = 0; i < optlen - 2; i++)
 613                                         ND_PRINT((ndo, "%02x", *(option + 2 + i)));
 614                         }
 615                         break;
 616                 case 40:
 617                         if (optlen > 2) {
 618                                 ND_PRINT((ndo, " 0x"));
 619                                 for (i = 0; i < optlen - 2; i++)
 620                                         ND_PRINT((ndo, "%02x", *(option + 2 + i)));
 621                         }
 622                         break;
 623                 case 41:
 624                         if (optlen == 4)
 625                                 ND_PRINT((ndo, " %u", EXTRACT_32BITS(option + 2)));
 626                         else
 627                                 ND_PRINT((ndo, " optlen != 4"));
 628                         break;
 629                 case 42:
 630                         if (optlen == 4)
 631                                 ND_PRINT((ndo, " %u", EXTRACT_32BITS(option + 2)));
 632                         else
 633                                 ND_PRINT((ndo, " optlen != 4"));
 634                         break;
 635                 case 43:
 636                         if (optlen == 6)
 637                                 ND_PRINT((ndo, " %u", EXTRACT_32BITS(option + 2)));
 638                         else if (optlen == 4)
 639                                 ND_PRINT((ndo, " %u", EXTRACT_16BITS(option + 2)));
 640                         else
 641                                 ND_PRINT((ndo, " optlen != 4 or 6"));
 642                         break;
 643                 case 44:
 644                         if (optlen > 2) {
 645                                 ND_PRINT((ndo, " "));
 646                                 for (i = 0; i < optlen - 2; i++)
 647                                         ND_PRINT((ndo, "%02x", *(option + 2 + i)));
 648                         }
 649                         break;
 650                 }
 651         }
 652
 653         return optlen;
 654 trunc:
 655         ND_PRINT((ndo, "%s", tstr));
 656         return 0;
 657 }