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 26static const char rcsid[] _U_ = 27 "@(#) $Header: /tcpdump/master/tcpdump/print-llc.c,v 1.61.2.9 2006/01/17 17:44:46 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 47static 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 66static 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 78static 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 89static const struct tok llc_ig_flag_values[] = { 90 { 0, "Individual" }, 91 { LLC_IG, "Group" }, 92 { 0, NULL } 93}; 94 95 96static const struct tok llc_supervisory_values[] = { 97 { 0, "Receiver Ready" }, 98 { 1, "Receiver not Ready" }, 99 { 2, "Reject" }, 100 { 0, NULL } 101}; 102 103 104static const struct tok cisco_values[] = { 105 { PID_CISCO_CDP, "CDP" }, 106 { 0, NULL } 107}; 108 109static const struct tok bridged_values[] = { 110 { PID_RFC2684_ETH_FCS, "Ethernet + FCS" }, 111 { PID_RFC2684_ETH_NOFCS, "Ethernet w/o FCS" }, 112 { PID_RFC2684_802_4_FCS, "802.4 + FCS" }, 113 { PID_RFC2684_802_4_NOFCS, "802.4 w/o FCS" }, 114 { PID_RFC2684_802_5_FCS, "Token Ring + FCS" }, 115 { PID_RFC2684_802_5_NOFCS, "Token Ring w/o FCS" }, 116 { PID_RFC2684_FDDI_FCS, "FDDI + FCS" }, 117 { PID_RFC2684_FDDI_NOFCS, "FDDI w/o FCS" }, 118 { PID_RFC2684_802_6_FCS, "802.6 + FCS" }, 119 { PID_RFC2684_802_6_NOFCS, "802.6 w/o FCS" }, 120 { PID_RFC2684_BPDU, "BPDU" }, 121 { 0, NULL }, 122}; 123 124static const struct tok null_values[] = { 125 { 0, NULL } 126}; 127 128struct oui_tok { 129 u_int32_t oui; 130 const struct tok *tok; 131}; 132 133static const struct oui_tok oui_to_tok[] = { 134 { OUI_ENCAP_ETHER, ethertype_values }, 135 { OUI_CISCO_90, ethertype_values }, /* uses some Ethertype values */ 136 { OUI_APPLETALK, ethertype_values }, /* uses some Ethertype values */ 137 { OUI_CISCO, cisco_values }, 138 { OUI_RFC2684, bridged_values }, /* bridged, RFC 2427 FR or RFC 2864 ATM */ 139 { 0, NULL } 140}; 141 142/* 143 * Returns non-zero IFF it succeeds in printing the header 144 */ 145int 146llc_print(const u_char *p, u_int length, u_int caplen, 147 const u_char *esrc, const u_char *edst, u_short *extracted_ethertype) 148{ 149 u_int8_t dsap_field, dsap, ssap_field, ssap; 150 u_int16_t control; 151 int is_u; 152 register int ret; 153 154 *extracted_ethertype = 0; 155 156 if (caplen < 3) { 157 (void)printf("[|llc]"); 158 default_print((u_char *)p, caplen); 159 return(0); 160 } 161 162 dsap_field = *p; 163 ssap_field = *(p + 1); 164 165 /* 166 * OK, what type of LLC frame is this? The length 167 * of the control field depends on that - I frames 168 * have a two-byte control field, and U frames have 169 * a one-byte control field. 170 */ 171 control = *(p + 2); 172 if ((control & LLC_U_FMT) == LLC_U_FMT) { 173 /* 174 * U frame. 175 */ 176 is_u = 1; 177 } else { 178 /* 179 * The control field in I and S frames is 180 * 2 bytes... 181 */ 182 if (caplen < 4) { 183 (void)printf("[|llc]"); 184 default_print((u_char *)p, caplen); 185 return(0); 186 } 187 188 /* 189 * ...and is little-endian. 190 */ 191 control = EXTRACT_LE_16BITS(p + 2); 192 is_u = 0; 193 } 194 195 if (ssap_field == LLCSAP_GLOBAL && dsap_field == LLCSAP_GLOBAL) { 196 /* 197 * This is an Ethernet_802.3 IPX frame; it has an 198 * 802.3 header (i.e., an Ethernet header where the 199 * type/length field is <= ETHERMTU, i.e. it's a length 200 * field, not a type field), but has no 802.2 header - 201 * the IPX packet starts right after the Ethernet header, 202 * with a signature of two bytes of 0xFF (which is 203 * LLCSAP_GLOBAL). 204 * 205 * (It might also have been an Ethernet_802.3 IPX at 206 * one time, but got bridged onto another network, 207 * such as an 802.11 network; this has appeared in at 208 * least one capture file.) 209 */ 210 211 if (eflag) 212 printf("IPX 802.3: "); 213 214 ipx_print(p, length); 215 return (1); 216 } 217 218 dsap = dsap_field & ~LLC_IG; 219 ssap = ssap_field & ~LLC_GSAP; 220 221 if (eflag) { 222 printf("LLC, dsap %s (0x%02x) %s, ssap %s (0x%02x) %s", 223 tok2str(llc_values, "Unknown", dsap), 224 dsap, 225 tok2str(llc_ig_flag_values, "Unknown", dsap_field & LLC_IG), 226 tok2str(llc_values, "Unknown", ssap), 227 ssap, 228 tok2str(llc_flag_values, "Unknown", ssap_field & LLC_GSAP)); 229 230 if (is_u) { 231 printf(", ctrl 0x%02x: ", control); 232 } else { 233 printf(", ctrl 0x%04x: ", control); 234 } 235 } 236 237 if (ssap == LLCSAP_8021D && dsap == LLCSAP_8021D && 238 control == LLC_UI) { 239 stp_print(p+3, length-3); 240 return (1); 241 } 242 243 if (ssap == LLCSAP_IP && dsap == LLCSAP_IP && 244 control == LLC_UI) { 245 ip_print(gndo, p+4, length-4); 246 return (1); 247 } 248 249 if (ssap == LLCSAP_IPX && dsap == LLCSAP_IPX && 250 control == LLC_UI) { 251 /* 252 * This is an Ethernet_802.2 IPX frame, with an 802.3 253 * header and an 802.2 LLC header with the source and 254 * destination SAPs being the IPX SAP. 255 * 256 * Skip DSAP, LSAP, and control field. 257 */ 258 if (eflag) 259 printf("IPX 802.2: "); 260 261 ipx_print(p+3, length-3); 262 return (1); 263 } 264 265#ifdef TCPDUMP_DO_SMB 266 if (ssap == LLCSAP_NETBEUI && dsap == LLCSAP_NETBEUI 267 && (!(control & LLC_S_FMT) || control == LLC_U_FMT)) { 268 /* 269 * we don't actually have a full netbeui parser yet, but the 270 * smb parser can handle many smb-in-netbeui packets, which 271 * is very useful, so we call that 272 * 273 * We don't call it for S frames, however, just I frames 274 * (which are frames that don't have the low-order bit, 275 * LLC_S_FMT, set in the first byte of the control field) 276 * and UI frames (whose control field is just 3, LLC_U_FMT). 277 */ 278 279 /* 280 * Skip the LLC header. 281 */ 282 if (is_u) { 283 p += 3; 284 length -= 3; 285 caplen -= 3; 286 } else { 287 p += 4; 288 length -= 4; 289 caplen -= 4; 290 } 291 netbeui_print(control, p, length); 292 return (1); 293 } 294#endif 295 if (ssap == LLCSAP_ISONS && dsap == LLCSAP_ISONS 296 && control == LLC_UI) { 297 isoclns_print(p + 3, length - 3, caplen - 3); 298 return (1); 299 } 300 301 if (ssap == LLCSAP_SNAP && dsap == LLCSAP_SNAP 302 && control == LLC_UI) { 303 /* 304 * XXX - what *is* the right bridge pad value here? 305 * Does anybody ever bridge one form of LAN traffic 306 * over a networking type that uses 802.2 LLC? 307 */ 308 ret = snap_print(p+3, length-3, caplen-3, extracted_ethertype, 309 2); 310 if (ret) 311 return (ret); 312 } 313 314 if (!eflag) { 315 if (ssap == dsap) { 316 if (esrc == NULL || edst == NULL) 317 (void)printf("%s ", tok2str(llc_values, "Unknown DSAP 0x%02x", dsap)); 318 else 319 (void)printf("%s > %s %s ", 320 etheraddr_string(esrc), 321 etheraddr_string(edst), 322 tok2str(llc_values, "Unknown DSAP 0x%02x", dsap)); 323 } else { 324 if (esrc == NULL || edst == NULL) 325 (void)printf("%s > %s ", 326 tok2str(llc_values, "Unknown SSAP 0x%02x", ssap), 327 tok2str(llc_values, "Unknown DSAP 0x%02x", dsap)); 328 else 329 (void)printf("%s %s > %s %s ", 330 etheraddr_string(esrc), 331 tok2str(llc_values, "Unknown SSAP 0x%02x", ssap), 332 etheraddr_string(edst), 333 tok2str(llc_values, "Unknown DSAP 0x%02x", dsap)); 334 } 335 } 336 337 if (is_u) { 338 printf("Unnumbered, %s, Flags [%s], length %u", 339 tok2str(llc_cmd_values, "%02x", LLC_U_CMD(control)), 340 tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_U_POLL)), 341 length); 342 343 p += 3; 344 length -= 3; 345 caplen -= 3; 346 347 if ((control & ~LLC_U_POLL) == LLC_XID) { 348 if (*p == LLC_XID_FI) { 349 printf(": %02x %02x", p[1], p[2]); 350 p += 3; 351 length -= 3; 352 caplen -= 3; 353 } 354 } 355 } else { 356 if ((control & LLC_S_FMT) == LLC_S_FMT) { 357 (void)printf("Supervisory, %s, rcv seq %u, Flags [%s], length %u", 358 tok2str(llc_supervisory_values,"?",LLC_S_CMD(control)), 359 LLC_IS_NR(control), 360 tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_IS_POLL)), 361 length); 362 } else { 363 (void)printf("Information, send seq %u, rcv seq %u, Flags [%s], length %u", 364 LLC_I_NS(control), 365 LLC_IS_NR(control), 366 tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_IS_POLL)), 367 length); 368 } 369 p += 4; 370 length -= 4; 371 caplen -= 4; 372 } 373 return(1); 374} 375 376int 377snap_print(const u_char *p, u_int length, u_int caplen, 378 u_short *extracted_ethertype, u_int bridge_pad) 379{ 380 u_int32_t orgcode; 381 register u_short et; 382 register int ret; 383 384 TCHECK2(*p, 5); 385 orgcode = EXTRACT_24BITS(p); 386 et = EXTRACT_16BITS(p + 3); 387 388 if (eflag) { 389 const struct tok *tok = null_values; 390 const struct oui_tok *otp; 391 392 for (otp = &oui_to_tok[0]; otp->tok != NULL; otp++) { 393 if (otp->oui == orgcode) { 394 tok = otp->tok; 395 break; 396 } 397 } 398 (void)printf("oui %s (0x%06x), %s %s (0x%04x): ", 399 tok2str(oui_values, "Unknown", orgcode), 400 orgcode, 401 (orgcode == 0x000000 ? "ethertype" : "pid"), 402 tok2str(tok, "Unknown", et), 403 et); 404 } 405 p += 5; 406 length -= 5; 407 caplen -= 5; 408 409 switch (orgcode) { 410 case OUI_ENCAP_ETHER: 411 case OUI_CISCO_90: 412 /* 413 * This is an encapsulated Ethernet packet, 414 * or a packet bridged by some piece of 415 * Cisco hardware; the protocol ID is 416 * an Ethernet protocol type. 417 */ 418 ret = ether_encap_print(et, p, length, caplen, 419 extracted_ethertype); 420 if (ret) 421 return (ret); 422 break; 423 424 case OUI_APPLETALK: 425 if (et == ETHERTYPE_ATALK) { 426 /* 427 * No, I have no idea why Apple used one 428 * of their own OUIs, rather than 429 * 0x000000, and an Ethernet packet 430 * type, for Appletalk data packets, 431 * but used 0x000000 and an Ethernet 432 * packet type for AARP packets. 433 */ 434 ret = ether_encap_print(et, p, length, caplen, 435 extracted_ethertype); 436 if (ret) 437 return (ret); 438 } 439 break; 440 441 case OUI_CISCO: 442 if (et == PID_CISCO_CDP) { 443 cdp_print(p, length, caplen); 444 return (1); 445 } 446 break; 447 448 case OUI_RFC2684: 449 switch (et) { 450 451 case PID_RFC2684_ETH_FCS: 452 case PID_RFC2684_ETH_NOFCS: 453 /* 454 * XXX - remove the last two bytes for 455 * PID_RFC2684_ETH_FCS? 456 */ 457 /* 458 * Skip the padding. 459 */ 460 TCHECK2(*p, bridge_pad); 461 caplen -= bridge_pad; 462 length -= bridge_pad; 463 p += bridge_pad; 464 465 /* 466 * What remains is an Ethernet packet. 467 */ 468 ether_print(p, length, caplen); 469 return (1); 470 471 case PID_RFC2684_802_5_FCS: 472 case PID_RFC2684_802_5_NOFCS: 473 /* 474 * XXX - remove the last two bytes for 475 * PID_RFC2684_ETH_FCS? 476 */ 477 /* 478 * Skip the padding, but not the Access 479 * Control field. 480 */ 481 TCHECK2(*p, bridge_pad); 482 caplen -= bridge_pad; 483 length -= bridge_pad; 484 p += bridge_pad; 485 486 /* 487 * What remains is an 802.5 Token Ring 488 * packet. 489 */ 490 token_print(p, length, caplen); 491 return (1); 492 493 case PID_RFC2684_FDDI_FCS: 494 case PID_RFC2684_FDDI_NOFCS: 495 /* 496 * XXX - remove the last two bytes for 497 * PID_RFC2684_ETH_FCS? 498 */ 499 /* 500 * Skip the padding. 501 */ 502 TCHECK2(*p, bridge_pad + 1); 503 caplen -= bridge_pad + 1; 504 length -= bridge_pad + 1; 505 p += bridge_pad + 1; 506 507 /* 508 * What remains is an FDDI packet. 509 */ 510 fddi_print(p, length, caplen); 511 return (1); 512 513 case PID_RFC2684_BPDU: 514 stp_print(p, length); 515 return (1); 516 } 517 } 518 return (0); 519 520trunc: 521 (void)printf("[|snap]"); 522 return (1); 523} 524 525 526/* 527 * Local Variables: 528 * c-style: whitesmith 529 * c-basic-offset: 8 530 * End: 531 */ 532