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

   1 /*
   2  * Copyright (c) 2015 Ritesh Ranjan (r.ranjan789@gmail.com)
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. The name of the author may not be used to endorse or promote products
  14  *    derived from this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  18  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  19  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
  20  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  22  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  24  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  25  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  26  * POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 /* \summary: - Locator/Identifier Separation Protocol (LISP) printer */
  30
  31 /*
  32  * specification: RFC 6830
  33  *
  34  *
  35  * The Map-Register message format is:
  36  *
  37  *       0                   1                   2                   3
  38  *       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
  39  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  40  *      |Type=3 |P|S|I|R|      Reserved               |M| Record Count  |
  41  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  42  *      |                         Nonce . . .                           |
  43  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  44  *      |                         . . . Nonce                           |
  45  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  46  *      |            Key ID             |  Authentication Data Length   |
  47  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  48  *      ~                     Authentication Data                       ~
  49  *  +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  50  *  |   |                          Record TTL                           |
  51  *  |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  52  *  R   | Locator Count | EID mask-len  | ACT |A|      Reserved         |
  53  *  e   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  54  *  c   | Rsvd  |  Map-Version Number   |        EID-Prefix-AFI         |
  55  *  o   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  56  *  r   |                          EID-Prefix                           |
  57  *  d   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  58  *  |  /|    Priority   |    Weight     |  M Priority   |   M Weight    |
  59  *  | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  60  *  | o |        Unused Flags     |L|p|R|           Loc-AFI             |
  61  *  | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  62  *  |  \|                             Locator                           |
  63  *  +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  64  *
  65  *
  66  * The Map-Notify message format is:
  67  *
  68  *       0                   1                   2                   3
  69  *       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
  70  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  71  *      |Type=4 |I|R|          Reserved                 | Record Count  |
  72  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  73  *      |                         Nonce . . .                           |
  74  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  75  *      |                         . . . Nonce                           |
  76  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  77  *      |            Key ID             |  Authentication Data Length   |
  78  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  79  *      ~                     Authentication Data                       ~
  80  *  +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  81  *  |   |                          Record TTL                           |
  82  *  |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  83  *  R   | Locator Count | EID mask-len  | ACT |A|      Reserved         |
  84  *  e   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  85  *  c   | Rsvd  |  Map-Version Number   |         EID-Prefix-AFI        |
  86  *  o   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  87  *  r   |                          EID-Prefix                           |
  88  *  d   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  89  *  |  /|    Priority   |    Weight     |  M Priority   |   M Weight    |
  90  *  | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  91  *  | o |        Unused Flags     |L|p|R|           Loc-AFI             |
  92  *  | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  93  *  |  \|                             Locator                           |
  94  *  +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  95  */
  96
  97 #ifdef HAVE_CONFIG_H
  98 #include "config.h"
  99 #endif
 100
 101 #include <netdissect-stdinc.h>
 102 #include "netdissect.h"
 103 #include <string.h>
 104 #include <stdlib.h>
 105
 106 #include "ip.h"
 107 #include "ip6.h"
 108
 109 #include "extract.h"
 110 #include "addrtoname.h"
 111
 112 static const char tstr[] = " [|LISP]";
 113
 114 #define IPv4_AFI                        1
 115 #define IPv6_AFI                        2
 116 #define TYPE_INDEX                      4
 117 #define LISP_MAP_NOTIFY_IBIT_MASK       8
 118 #define LISP_MAP_REGISTER_IBIT_MASK     2
 119
 120 enum {
 121         LISP_MAP_REQUEST = 1,
 122         LISP_MAP_REPLY,
 123         LISP_MAP_REGISTER,
 124         LISP_MAP_NOTIFY,
 125         LISP_ENCAPSULATED_CONTROL_MESSAGE = 8
 126 };
 127
 128 enum {
 129         LISP_AUTH_NONE,
 130         LISP_AUTH_SHA1,
 131         LISP_AUTH_SHA256
 132 };
 133
 134 static const struct tok lisp_type [] = {
 135         { 0, "LISP-Reserved"                    },
 136         { 1, "LISP-Map-Request"                 },
 137         { 2, "LISP-Map-Reply"                   },
 138         { 3, "LISP-Map-Register"                },
 139         { 4, "LISP-Map-Notify"                  },
 140         { 8, "LISP-Encapsulated-Contol-Message" },
 141         { 0, NULL }
 142 };
 143
 144 /*
 145  * P-Bit : Request for Proxy Map-Reply from the MS/MR
 146  * S-Bit : Security Enhancement. ETR is LISP-SEC enabled. draft-ietf-lisp-sec
 147  * I-Bit : 128 bit xTR-ID and 64 bit Site-ID present.
 148  *         xTR-ID and Site-ID help in differentiation of xTRs in multi xTR
 149  *         and multi Site deployment scenarios.
 150  * R-Bit : Built for a Reencapsulating-Tunnel-Router. Used in Traffic
 151  *         Engineering and Service Chaining
 152  */
 153 static const struct tok map_register_hdr_flag[] = {
 154         { 0x08000000, "P-Proxy-Map-Reply"  },
 155         { 0x04000000, "S-LISP-SEC-Capable" },
 156         { 0x02000000, "I-xTR-ID-Present"   },
 157         { 0x01000000, "R-Build-For-RTR"    },
 158         { 0x00000100, "M-Want-Map-Notify"  },
 159         { 0, NULL }
 160 };
 161
 162 static const struct tok map_notify_hdr_flag[] = {
 163         { 0x08000000, "I-xTR-ID-Present"   },
 164         { 0x04000000, "R-Build-For-RTR"    },
 165         { 0, NULL }
 166 };
 167
 168 static const struct tok auth_type[] = {
 169         { LISP_AUTH_NONE,   "None"   },
 170         { LISP_AUTH_SHA1,   "SHA1"   },
 171         { LISP_AUTH_SHA256, "SHA256" },
 172         { 0, NULL}
 173 };
 174
 175 static const struct tok lisp_eid_action[] = {
 176         { 0, "No-Action"        },
 177         { 1, "Natively-Forward" },
 178         { 2, "Send-Map-Request" },
 179         { 3, "Drop"             },
 180         { 0, NULL}
 181 };
 182
 183 static const struct tok lisp_loc_flag[] = {
 184         { 0x0004, "Local-Locator" },
 185         { 0x0002, "RLoc-Probed"   },
 186         { 0x0001, "Reachable"     },
 187         { 0, NULL }
 188 };
 189
 190 typedef struct map_register_hdr {
 191         nd_uint8_t type_and_flag;
 192         nd_uint8_t reserved;
 193         nd_uint8_t reserved_and_flag2;
 194         nd_uint8_t record_count;
 195         nd_uint64_t nonce;
 196         nd_uint16_t key_id;
 197         nd_uint16_t auth_data_len;
 198 } lisp_map_register_hdr;
 199
 200 #define MAP_REGISTER_HDR_LEN sizeof(lisp_map_register_hdr)
 201
 202 typedef struct map_register_eid {
 203         nd_uint32_t ttl;
 204         nd_uint8_t locator_count;
 205         nd_uint8_t eid_prefix_mask_length;
 206         nd_uint8_t act_auth_inc_res;
 207         nd_uint8_t reserved;
 208         nd_uint8_t reserved_version_hi;
 209         nd_uint8_t version_low;
 210         nd_uint16_t eid_prefix_afi;
 211 } lisp_map_register_eid;
 212
 213 #define MAP_REGISTER_EID_LEN sizeof(lisp_map_register_eid)
 214
 215 typedef struct map_register_loc {
 216         nd_uint8_t priority;
 217         nd_uint8_t weight;
 218         nd_uint8_t m_priority;
 219         nd_uint8_t m_weight;
 220         nd_uint16_t unused_and_flag;
 221         nd_uint16_t locator_afi;
 222 } lisp_map_register_loc;
 223
 224 #define MAP_REGISTER_LOC_LEN sizeof(lisp_map_register_loc)
 225
 226 static inline uint8_t extract_lisp_type(uint8_t);
 227 static inline uint8_t is_xtr_data_present(uint8_t , uint8_t);
 228 static void lisp_hdr_flag(netdissect_options *, const lisp_map_register_hdr *);
 229 static void action_flag(netdissect_options *, uint8_t);
 230 static void loc_hdr_flag(netdissect_options *, uint16_t);
 231
 232 void lisp_print(netdissect_options *ndo, const u_char *bp, u_int length)
 233 {
 234         uint8_t type;
 235         uint8_t mask_len;
 236         uint8_t loc_count;
 237         uint8_t xtr_present;
 238         uint8_t record_count;
 239         uint16_t key_id;
 240         uint16_t eid_afi;
 241         uint16_t loc_afi;
 242         uint16_t map_version;
 243         uint16_t packet_offset;
 244         uint16_t auth_data_len;
 245         uint32_t ttl;
 246         const u_char *packet_iterator;
 247         const u_char *loc_ip_pointer;
 248         const lisp_map_register_hdr *lisp_hdr;
 249         const lisp_map_register_eid *lisp_eid;
 250         const lisp_map_register_loc *lisp_loc;
 251
 252         /* Check if enough bytes for header are available */
 253         ND_TCHECK2(*bp, MAP_REGISTER_HDR_LEN);
 254         lisp_hdr = (const lisp_map_register_hdr *) bp;
 255         lisp_hdr_flag(ndo, lisp_hdr);
 256         /* Supporting only MAP NOTIFY and MAP REGISTER LISP packets */
 257         type = extract_lisp_type(lisp_hdr->type_and_flag);
 258         if ((type != LISP_MAP_REGISTER) && (type != LISP_MAP_NOTIFY))
 259                 return;
 260
 261         /* Find if the packet contains xTR and Site-ID data */
 262         xtr_present = is_xtr_data_present(type, lisp_hdr->type_and_flag);
 263
 264         /* Extract the number of EID records present */
 265         auth_data_len = EXTRACT_16BITS(&lisp_hdr->auth_data_len);
 266         packet_iterator = (const u_char *)(lisp_hdr);
 267         packet_offset = MAP_REGISTER_HDR_LEN;
 268         record_count = lisp_hdr->record_count;
 269
 270         if (ndo->ndo_vflag) {
 271                 key_id = EXTRACT_16BITS(&lisp_hdr->key_id);
 272                 ND_PRINT((ndo, "\n    %u record(s), ", record_count));
 273                 ND_PRINT((ndo, "Authentication %s,",
 274                         tok2str(auth_type, "unknown-type", key_id)));
 275                 hex_print(ndo, "\n    Authentication-Data: ", packet_iterator +
 276                                                 packet_offset, auth_data_len);
 277         } else {
 278                 ND_PRINT((ndo, " %u record(s),", record_count));
 279         }
 280         packet_offset += auth_data_len;
 281
 282         if (record_count == 0)
 283                 goto invalid;
 284
 285         /* Print all the EID records */
 286         while ((length > packet_offset) && (record_count--)) {
 287
 288                 ND_TCHECK2(*(packet_iterator + packet_offset), MAP_REGISTER_EID_LEN);
 289                 ND_PRINT((ndo, "\n"));
 290                 lisp_eid = (const lisp_map_register_eid *)
 291                                 ((const u_char *)lisp_hdr + packet_offset);
 292                 packet_offset += MAP_REGISTER_EID_LEN;
 293                 mask_len = lisp_eid->eid_prefix_mask_length;
 294                 eid_afi = EXTRACT_16BITS(&lisp_eid->eid_prefix_afi);
 295                 loc_count = lisp_eid->locator_count;
 296
 297                 if (ndo->ndo_vflag) {
 298                         ttl = EXTRACT_32BITS(&lisp_eid->ttl);
 299                         ND_PRINT((ndo, "      Record TTL %u,", ttl));
 300                         action_flag(ndo, lisp_eid->act_auth_inc_res);
 301                         map_version = (((lisp_eid->reserved_version_hi) & 15 ) * 255) +
 302                                         lisp_eid->version_low;
 303                         ND_PRINT((ndo, " Map Version: %u,", map_version));
 304                 }
 305
 306                 switch (eid_afi) {
 307                 case IPv4_AFI:
 308                         ND_TCHECK2(*(packet_iterator + packet_offset), 4);
 309                         ND_PRINT((ndo, " EID %s/%u,", ipaddr_string(ndo,
 310                                 packet_iterator + packet_offset), mask_len));
 311                         packet_offset += 4;
 312                         break;
 313                 case IPv6_AFI:
 314                         ND_TCHECK2(*(packet_iterator + packet_offset), 16);
 315                         ND_PRINT((ndo, " EID %s/%u,", ip6addr_string(ndo,
 316                                 packet_iterator + packet_offset), mask_len));
 317                         packet_offset += 16;
 318                         break;
 319                 default:
 320                         /*
 321                          * No support for LCAF right now.
 322                          */
 323                         return;
 324                         break;
 325                 }
 326
 327                 ND_PRINT((ndo, " %u locator(s)", loc_count));
 328
 329                 while (loc_count--) {
 330                         ND_TCHECK2(*(packet_iterator + packet_offset), MAP_REGISTER_LOC_LEN);
 331                         lisp_loc = (const lisp_map_register_loc *) (packet_iterator + packet_offset);
 332                         loc_ip_pointer = (const u_char *) (lisp_loc + 1);
 333                         packet_offset += MAP_REGISTER_LOC_LEN;
 334                         loc_afi = EXTRACT_16BITS(&lisp_loc->locator_afi);
 335
 336                         if (ndo->ndo_vflag)
 337                                 ND_PRINT((ndo, "\n       "));
 338
 339                         switch (loc_afi) {
 340                         case IPv4_AFI:
 341                                 ND_TCHECK2(*(packet_iterator + packet_offset), 4);
 342                                 ND_PRINT((ndo, " LOC %s", ipaddr_string(ndo, loc_ip_pointer)));
 343                                 packet_offset += 4;
 344                                 break;
 345                         case IPv6_AFI:
 346                                 ND_TCHECK2(*(packet_iterator + packet_offset), 16);
 347                                 ND_PRINT((ndo, " LOC %s", ip6addr_string(ndo, loc_ip_pointer)));
 348                                 packet_offset += 16;
 349                                 break;
 350                         default:
 351                                 break;
 352                         }
 353                         if (ndo->ndo_vflag) {
 354                                 ND_PRINT((ndo, "\n          Priority/Weight %u/%u,"
 355                                                 " Multicast Priority/Weight %u/%u,",
 356                                                 lisp_loc->priority, lisp_loc->weight,
 357                                                 lisp_loc->m_priority, lisp_loc->m_weight));
 358                                 loc_hdr_flag(ndo, EXTRACT_16BITS(&lisp_loc->unused_and_flag));
 359                         }
 360                 }
 361         }
 362
 363         /*
 364          * Print xTR and Site ID. Handle the fact that the packet could be invalid.
 365          * If the xTR_ID_Present bit is not set, and we still have data to display,
 366          * show it as hex data.
 367          */
 368         if (xtr_present) {
 369                 if (!ND_TTEST2(*(packet_iterator + packet_offset), 24))
 370                         goto invalid;
 371                 hex_print_with_offset(ndo, "\n    xTR-ID: ", packet_iterator + packet_offset, 16, 0);
 372                 ND_PRINT((ndo, "\n    SITE-ID: %" PRIu64,
 373                         EXTRACT_64BITS(packet_iterator + packet_offset + 16)));
 374         } else {
 375                 /* Check if packet isn't over yet */
 376                 if (packet_iterator + packet_offset < ndo->ndo_snapend) {
 377                         hex_print_with_offset(ndo, "\n    Data: ", packet_iterator + packet_offset,
 378                                 (ndo->ndo_snapend - (packet_iterator + packet_offset)), 0);
 379                 }
 380         }
 381         return;
 382 trunc:
 383         ND_PRINT((ndo, "\n   %s", tstr));
 384         return;
 385 invalid:
 386         ND_PRINT((ndo, "\n   %s", istr));
 387         return;
 388 }
 389
 390 static inline uint8_t extract_lisp_type(uint8_t lisp_hdr_flags)
 391 {
 392         return (lisp_hdr_flags) >> TYPE_INDEX;
 393 }
 394
 395 static inline uint8_t is_xtr_data_present(uint8_t type, uint8_t lisp_hdr_flags)
 396 {
 397         uint8_t xtr_present = 0;
 398
 399         if (type == LISP_MAP_REGISTER)
 400                 xtr_present = (lisp_hdr_flags) & LISP_MAP_REGISTER_IBIT_MASK;
 401         else if (type == LISP_MAP_NOTIFY)
 402                 xtr_present = (lisp_hdr_flags) & LISP_MAP_NOTIFY_IBIT_MASK;
 403
 404         return xtr_present;
 405 }
 406
 407 static void lisp_hdr_flag(netdissect_options *ndo, const lisp_map_register_hdr *lisp_hdr)
 408 {
 409         uint8_t type = extract_lisp_type(lisp_hdr->type_and_flag);
 410
 411         if (!ndo->ndo_vflag) {
 412                 ND_PRINT((ndo, "%s,", tok2str(lisp_type, "unknown-type-%u", type)));
 413                 return;
 414         } else {
 415                 ND_PRINT((ndo, "%s,", tok2str(lisp_type, "unknown-type-%u", type)));
 416         }
 417
 418         if (type == LISP_MAP_REGISTER) {
 419                 ND_PRINT((ndo, " flags [%s],", bittok2str(map_register_hdr_flag,
 420                          "none", EXTRACT_32BITS(lisp_hdr))));
 421         } else if (type == LISP_MAP_NOTIFY) {
 422                 ND_PRINT((ndo, " flags [%s],", bittok2str(map_notify_hdr_flag,
 423                          "none", EXTRACT_32BITS(lisp_hdr))));
 424         }
 425
 426         return;
 427 }
 428
 429 static void action_flag(netdissect_options *ndo, uint8_t act_auth_inc_res)
 430 {
 431         uint8_t action;
 432         uint8_t authoritative;
 433
 434         authoritative  = ((act_auth_inc_res >> 4) & 1);
 435
 436         if (authoritative)
 437                 ND_PRINT((ndo, " Authoritative,"));
 438         else
 439                 ND_PRINT((ndo, " Non-Authoritative,"));
 440
 441         action = act_auth_inc_res >> 5;
 442         ND_PRINT((ndo, " %s,", tok2str(lisp_eid_action, "unknown", action)));
 443 }
 444
 445 static void loc_hdr_flag(netdissect_options *ndo, uint16_t flag)
 446 {
 447         ND_PRINT((ndo, " flags [%s],", bittok2str(lisp_loc_flag, "none", flag)));
 448 }
 449