1 /* 2 * Copyright (c) 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 * Code by Matt Thomas, Digital Equipment Corporation 22 * with an awful lot of hacking by Jeffrey Mogul, DECWRL 23 */ 24 25 #ifndef lint 26 static const char rcsid[] _U_ = 27 "@(#) $Header: /tcpdump/master/tcpdump/print-llc.c,v 1.75 2007-04-13 09:43:11 hannes Exp $"; 28 #endif 29 30 #ifdef HAVE_CONFIG_H 31 #include "config.h" 32 #endif 33 34 #include <tcpdump-stdinc.h> 35 36 #include <stdio.h> 37 #include <string.h> 38 39 #include "interface.h" 40 #include "addrtoname.h" 41 #include "extract.h" /* must come after interface.h */ 42 43 #include "llc.h" 44 #include "ethertype.h" 45 #include "oui.h" 46 47 static const struct tok llc_values[] = { 48 { LLCSAP_NULL, "Null" }, 49 { LLCSAP_GLOBAL, "Global" }, 50 { LLCSAP_8021B_I, "802.1B I" }, 51 { LLCSAP_8021B_G, "802.1B G" }, 52 { LLCSAP_IP, "IP" }, 53 { LLCSAP_SNA, "SNA" }, 54 { LLCSAP_PROWAYNM, "ProWay NM" }, 55 { LLCSAP_8021D, "STP" }, 56 { LLCSAP_RS511, "RS511" }, 57 { LLCSAP_ISO8208, "ISO8208" }, 58 { LLCSAP_PROWAY, "ProWay" }, 59 { LLCSAP_SNAP, "SNAP" }, 60 { LLCSAP_IPX, "IPX" }, 61 { LLCSAP_NETBEUI, "NetBeui" }, 62 { LLCSAP_ISONS, "OSI" }, 63 { 0, NULL }, 64 }; 65 66 static const struct tok llc_cmd_values[] = { 67 { LLC_UI, "ui" }, 68 { LLC_TEST, "test" }, 69 { LLC_XID, "xid" }, 70 { LLC_UA, "ua" }, 71 { LLC_DISC, "disc" }, 72 { LLC_DM, "dm" }, 73 { LLC_SABME, "sabme" }, 74 { LLC_FRMR, "frmr" }, 75 { 0, NULL } 76 }; 77 78 static const struct tok llc_flag_values[] = { 79 { 0, "Command" }, 80 { LLC_GSAP, "Response" }, 81 { LLC_U_POLL, "Poll" }, 82 { LLC_GSAP|LLC_U_POLL, "Final" }, 83 { LLC_IS_POLL, "Poll" }, 84 { LLC_GSAP|LLC_IS_POLL, "Final" }, 85 { 0, NULL } 86 }; 87 88 89 static const struct tok llc_ig_flag_values[] = { 90 { 0, "Individual" }, 91 { LLC_IG, "Group" }, 92 { 0, NULL } 93 }; 94 95 96 static const struct tok llc_supervisory_values[] = { 97 { 0, "Receiver Ready" }, 98 { 1, "Receiver not Ready" }, 99 { 2, "Reject" }, 100 { 0, NULL } 101 }; 102 103 104 static const struct tok cisco_values[] = { 105 { PID_CISCO_CDP, "CDP" }, 106 { PID_CISCO_VTP, "VTP" }, 107 { PID_CISCO_DTP, "DTP" }, 108 { PID_CISCO_UDLD, "UDLD" }, 109 { PID_CISCO_PVST, "PVST" }, 110 { PID_CISCO_VLANBRIDGE, "VLAN Bridge" }, 111 { 0, NULL } 112 }; 113 114 static const struct tok bridged_values[] = { 115 { PID_RFC2684_ETH_FCS, "Ethernet + FCS" }, 116 { PID_RFC2684_ETH_NOFCS, "Ethernet w/o FCS" }, 117 { PID_RFC2684_802_4_FCS, "802.4 + FCS" }, 118 { PID_RFC2684_802_4_NOFCS, "802.4 w/o FCS" }, 119 { PID_RFC2684_802_5_FCS, "Token Ring + FCS" }, 120 { PID_RFC2684_802_5_NOFCS, "Token Ring w/o FCS" }, 121 { PID_RFC2684_FDDI_FCS, "FDDI + FCS" }, 122 { PID_RFC2684_FDDI_NOFCS, "FDDI w/o FCS" }, 123 { PID_RFC2684_802_6_FCS, "802.6 + FCS" }, 124 { PID_RFC2684_802_6_NOFCS, "802.6 w/o FCS" }, 125 { PID_RFC2684_BPDU, "BPDU" }, 126 { 0, NULL }, 127 }; 128 129 static const struct tok null_values[] = { 130 { 0, NULL } 131 }; 132 133 struct oui_tok { 134 u_int32_t oui; 135 const struct tok *tok; 136 }; 137 138 static const struct oui_tok oui_to_tok[] = { 139 { OUI_ENCAP_ETHER, ethertype_values }, 140 { OUI_CISCO_90, ethertype_values }, /* uses some Ethertype values */ 141 { OUI_APPLETALK, ethertype_values }, /* uses some Ethertype values */ 142 { OUI_CISCO, cisco_values }, 143 { OUI_RFC2684, bridged_values }, /* bridged, RFC 2427 FR or RFC 2864 ATM */ 144 { 0, NULL } 145 }; 146 147 /* 148 * Returns non-zero IFF it succeeds in printing the header 149 */ 150 int 151 llc_print(const u_char *p, u_int length, u_int caplen, 152 const u_char *esrc, const u_char *edst, u_short *extracted_ethertype) 153 { 154 u_int8_t dsap_field, dsap, ssap_field, ssap; 155 u_int16_t control; 156 int is_u; 157 register int ret; 158 159 *extracted_ethertype = 0; 160 161 if (caplen < 3) { 162 (void)printf("[|llc]"); 163 default_print((u_char *)p, caplen); 164 return(0); 165 } 166 167 dsap_field = *p; 168 ssap_field = *(p + 1); 169 170 /* 171 * OK, what type of LLC frame is this? The length 172 * of the control field depends on that - I frames 173 * have a two-byte control field, and U frames have 174 * a one-byte control field. 175 */ 176 control = *(p + 2); 177 if ((control & LLC_U_FMT) == LLC_U_FMT) { 178 /* 179 * U frame. 180 */ 181 is_u = 1; 182 } else { 183 /* 184 * The control field in I and S frames is 185 * 2 bytes... 186 */ 187 if (caplen < 4) { 188 (void)printf("[|llc]"); 189 default_print((u_char *)p, caplen); 190 return(0); 191 } 192 193 /* 194 * ...and is little-endian. 195 */ 196 control = EXTRACT_LE_16BITS(p + 2); 197 is_u = 0; 198 } 199 200 if (ssap_field == LLCSAP_GLOBAL && dsap_field == LLCSAP_GLOBAL) { 201 /* 202 * This is an Ethernet_802.3 IPX frame; it has an 203 * 802.3 header (i.e., an Ethernet header where the 204 * type/length field is <= ETHERMTU, i.e. it's a length 205 * field, not a type field), but has no 802.2 header - 206 * the IPX packet starts right after the Ethernet header, 207 * with a signature of two bytes of 0xFF (which is 208 * LLCSAP_GLOBAL). 209 * 210 * (It might also have been an Ethernet_802.3 IPX at 211 * one time, but got bridged onto another network, 212 * such as an 802.11 network; this has appeared in at 213 * least one capture file.) 214 */ 215 216 if (eflag) 217 printf("IPX 802.3: "); 218 219 ipx_print(p, length); 220 return (1); 221 } 222 223 dsap = dsap_field & ~LLC_IG; 224 ssap = ssap_field & ~LLC_GSAP; 225 226 if (eflag) { 227 printf("LLC, dsap %s (0x%02x) %s, ssap %s (0x%02x) %s", 228 tok2str(llc_values, "Unknown", dsap), 229 dsap, 230 tok2str(llc_ig_flag_values, "Unknown", dsap_field & LLC_IG), 231 tok2str(llc_values, "Unknown", ssap), 232 ssap, 233 tok2str(llc_flag_values, "Unknown", ssap_field & LLC_GSAP)); 234 235 if (is_u) { 236 printf(", ctrl 0x%02x: ", control); 237 } else { 238 printf(", ctrl 0x%04x: ", control); 239 } 240 } 241 242 if (ssap == LLCSAP_8021D && dsap == LLCSAP_8021D && 243 control == LLC_UI) { 244 stp_print(p+3, length-3); 245 return (1); 246 } 247 248 if (ssap == LLCSAP_IP && dsap == LLCSAP_IP && 249 control == LLC_UI) { 250 ip_print(gndo, p+4, length-4); 251 return (1); 252 } 253 254 if (ssap == LLCSAP_IPX && dsap == LLCSAP_IPX && 255 control == LLC_UI) { 256 /* 257 * This is an Ethernet_802.2 IPX frame, with an 802.3 258 * header and an 802.2 LLC header with the source and 259 * destination SAPs being the IPX SAP. 260 * 261 * Skip DSAP, LSAP, and control field. 262 */ 263 if (eflag) 264 printf("IPX 802.2: "); 265 266 ipx_print(p+3, length-3); 267 return (1); 268 } 269 270 #ifdef TCPDUMP_DO_SMB 271 if (ssap == LLCSAP_NETBEUI && dsap == LLCSAP_NETBEUI 272 && (!(control & LLC_S_FMT) || control == LLC_U_FMT)) { 273 /* 274 * we don't actually have a full netbeui parser yet, but the 275 * smb parser can handle many smb-in-netbeui packets, which 276 * is very useful, so we call that 277 * 278 * We don't call it for S frames, however, just I frames 279 * (which are frames that don't have the low-order bit, 280 * LLC_S_FMT, set in the first byte of the control field) 281 * and UI frames (whose control field is just 3, LLC_U_FMT). 282 */ 283 284 /* 285 * Skip the LLC header. 286 */ 287 if (is_u) { 288 p += 3; 289 length -= 3; 290 caplen -= 3; 291 } else { 292 p += 4; 293 length -= 4; 294 caplen -= 4; 295 } 296 netbeui_print(control, p, length); 297 return (1); 298 } 299 #endif 300 if (ssap == LLCSAP_ISONS && dsap == LLCSAP_ISONS 301 && control == LLC_UI) { 302 isoclns_print(p + 3, length - 3, caplen - 3); 303 return (1); 304 } 305 306 if (ssap == LLCSAP_SNAP && dsap == LLCSAP_SNAP 307 && control == LLC_UI) { 308 /* 309 * XXX - what *is* the right bridge pad value here? 310 * Does anybody ever bridge one form of LAN traffic 311 * over a networking type that uses 802.2 LLC? 312 */ 313 ret = snap_print(p+3, length-3, caplen-3, 2); 314 if (ret) 315 return (ret); 316 } 317 318 if (!eflag) { 319 if (ssap == dsap) { 320 if (esrc == NULL || edst == NULL) 321 (void)printf("%s ", tok2str(llc_values, "Unknown DSAP 0x%02x", dsap)); 322 else 323 (void)printf("%s > %s %s ", 324 etheraddr_string(esrc), 325 etheraddr_string(edst), 326 tok2str(llc_values, "Unknown DSAP 0x%02x", dsap)); 327 } else { 328 if (esrc == NULL || edst == NULL) 329 (void)printf("%s > %s ", 330 tok2str(llc_values, "Unknown SSAP 0x%02x", ssap), 331 tok2str(llc_values, "Unknown DSAP 0x%02x", dsap)); 332 else 333 (void)printf("%s %s > %s %s ", 334 etheraddr_string(esrc), 335 tok2str(llc_values, "Unknown SSAP 0x%02x", ssap), 336 etheraddr_string(edst), 337 tok2str(llc_values, "Unknown DSAP 0x%02x", dsap)); 338 } 339 } 340 341 if (is_u) { 342 printf("Unnumbered, %s, Flags [%s], length %u", 343 tok2str(llc_cmd_values, "%02x", LLC_U_CMD(control)), 344 tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_U_POLL)), 345 length); 346 347 p += 3; 348 length -= 3; 349 caplen -= 3; 350 351 if ((control & ~LLC_U_POLL) == LLC_XID) { 352 if (*p == LLC_XID_FI) { 353 printf(": %02x %02x", p[1], p[2]); 354 p += 3; 355 length -= 3; 356 caplen -= 3; 357 } 358 } 359 } else { 360 if ((control & LLC_S_FMT) == LLC_S_FMT) { 361 (void)printf("Supervisory, %s, rcv seq %u, Flags [%s], length %u", 362 tok2str(llc_supervisory_values,"?",LLC_S_CMD(control)), 363 LLC_IS_NR(control), 364 tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_IS_POLL)), 365 length); 366 } else { 367 (void)printf("Information, send seq %u, rcv seq %u, Flags [%s], length %u", 368 LLC_I_NS(control), 369 LLC_IS_NR(control), 370 tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_IS_POLL)), 371 length); 372 } 373 p += 4; 374 length -= 4; 375 caplen -= 4; 376 } 377 return(1); 378 } 379 380 int 381 snap_print(const u_char *p, u_int length, u_int caplen, u_int bridge_pad) 382 { 383 u_int32_t orgcode; 384 register u_short et; 385 register int ret; 386 387 TCHECK2(*p, 5); 388 orgcode = EXTRACT_24BITS(p); 389 et = EXTRACT_16BITS(p + 3); 390 391 if (eflag) { 392 const struct tok *tok = null_values; 393 const struct oui_tok *otp; 394 395 for (otp = &oui_to_tok[0]; otp->tok != NULL; otp++) { 396 if (otp->oui == orgcode) { 397 tok = otp->tok; 398 break; 399 } 400 } 401 (void)printf("oui %s (0x%06x), %s %s (0x%04x): ", 402 tok2str(oui_values, "Unknown", orgcode), 403 orgcode, 404 (orgcode == 0x000000 ? "ethertype" : "pid"), 405 tok2str(tok, "Unknown", et), 406 et); 407 } 408 p += 5; 409 length -= 5; 410 caplen -= 5; 411 412 switch (orgcode) { 413 case OUI_ENCAP_ETHER: 414 case OUI_CISCO_90: 415 /* 416 * This is an encapsulated Ethernet packet, 417 * or a packet bridged by some piece of 418 * Cisco hardware; the protocol ID is 419 * an Ethernet protocol type. 420 */ 421 ret = ethertype_print(gndo, et, p, length, caplen); 422 if (ret) 423 return (ret); 424 break; 425 426 case OUI_APPLETALK: 427 if (et == ETHERTYPE_ATALK) { 428 /* 429 * No, I have no idea why Apple used one 430 * of their own OUIs, rather than 431 * 0x000000, and an Ethernet packet 432 * type, for Appletalk data packets, 433 * but used 0x000000 and an Ethernet 434 * packet type for AARP packets. 435 */ 436 ret = ethertype_print(gndo, et, p, length, caplen); 437 if (ret) 438 return (ret); 439 } 440 break; 441 442 case OUI_CISCO: 443 switch (et) { 444 case PID_CISCO_CDP: 445 cdp_print(p, length, caplen); 446 return (1); 447 case PID_CISCO_DTP: 448 dtp_print(p, length); 449 return (1); 450 case PID_CISCO_UDLD: 451 udld_print(p, length); 452 return (1); 453 case PID_CISCO_VTP: 454 vtp_print(p, length); 455 return (1); 456 case PID_CISCO_PVST: 457 case PID_CISCO_VLANBRIDGE: 458 stp_print(p, length); 459 return (1); 460 default: 461 break; 462 } 463 464 case OUI_RFC2684: 465 switch (et) { 466 467 case PID_RFC2684_ETH_FCS: 468 case PID_RFC2684_ETH_NOFCS: 469 /* 470 * XXX - remove the last two bytes for 471 * PID_RFC2684_ETH_FCS? 472 */ 473 /* 474 * Skip the padding. 475 */ 476 TCHECK2(*p, bridge_pad); 477 caplen -= bridge_pad; 478 length -= bridge_pad; 479 p += bridge_pad; 480 481 /* 482 * What remains is an Ethernet packet. 483 */ 484 ether_print(gndo, p, length, caplen, NULL, NULL); 485 return (1); 486 487 case PID_RFC2684_802_5_FCS: 488 case PID_RFC2684_802_5_NOFCS: 489 /* 490 * XXX - remove the last two bytes for 491 * PID_RFC2684_ETH_FCS? 492 */ 493 /* 494 * Skip the padding, but not the Access 495 * Control field. 496 */ 497 TCHECK2(*p, bridge_pad); 498 caplen -= bridge_pad; 499 length -= bridge_pad; 500 p += bridge_pad; 501 502 /* 503 * What remains is an 802.5 Token Ring 504 * packet. 505 */ 506 token_print(p, length, caplen); 507 return (1); 508 509 case PID_RFC2684_FDDI_FCS: 510 case PID_RFC2684_FDDI_NOFCS: 511 /* 512 * XXX - remove the last two bytes for 513 * PID_RFC2684_ETH_FCS? 514 */ 515 /* 516 * Skip the padding. 517 */ 518 TCHECK2(*p, bridge_pad + 1); 519 caplen -= bridge_pad + 1; 520 length -= bridge_pad + 1; 521 p += bridge_pad + 1; 522 523 /* 524 * What remains is an FDDI packet. 525 */ 526 fddi_print(p, length, caplen); 527 return (1); 528 529 case PID_RFC2684_BPDU: 530 stp_print(p, length); 531 return (1); 532 } 533 } 534 return (0); 535 536 trunc: 537 (void)printf("[|snap]"); 538 return (1); 539 } 540 541 542 /* 543 * Local Variables: 544 * c-style: whitesmith 545 * c-basic-offset: 8 546 * End: 547 */ 548
