1 /* $OpenBSD: print-llc.c,v 1.17 2007/10/07 16:41:05 deraadt Exp $ */ 2 3 /* 4 * Copyright (c) 1992, 1993, 1994, 1995, 1996, 1997 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that: (1) source code distributions 9 * retain the above copyright notice and this paragraph in its entirety, (2) 10 * distributions including binary code include the above copyright notice and 11 * this paragraph in its entirety in the documentation or other materials 12 * provided with the distribution, and (3) all advertising materials mentioning 13 * features or use of this software display the following acknowledgement: 14 * ``This product includes software developed by the University of California, 15 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of 16 * the University nor the names of its contributors may be used to endorse 17 * or promote products derived from this software without specific prior 18 * written permission. 19 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 20 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 21 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 22 * 23 * Code by Matt Thomas, Digital Equipment Corporation 24 * with an awful lot of hacking by Jeffrey Mogul, DECWRL 25 */ 26 27 #ifndef lint 28 static const char rcsid[] = 29 "@(#) $Id: print-llc.c,v 1.17 2007/10/07 16:41:05 deraadt Exp $"; 30 #endif 31 32 #include <sys/param.h> 33 #include <sys/time.h> 34 35 #include <netinet/in.h> 36 37 #include <ctype.h> 38 #include <netdb.h> 39 #include <signal.h> 40 #include <stdio.h> 41 #include <string.h> 42 43 #include "interface.h" 44 #include "addrtoname.h" 45 #include "extract.h" /* must come after interface.h */ 46 #include "ethertype.h" 47 48 #include "llc.h" 49 50 static struct tok cmd2str[] = { 51 { LLC_UI, "ui" }, 52 { LLC_TEST, "test" }, 53 { LLC_XID, "xid" }, 54 { LLC_UA, "ua" }, 55 { LLC_DISC, "disc" }, 56 { LLC_DM, "dm" }, 57 { LLC_SABME, "sabme" }, 58 { LLC_FRMR, "frmr" }, 59 { 0, NULL } 60 }; 61 62 /* 63 * Returns non-zero IFF it succeeds in printing the header 64 */ 65 int 66 llc_print(const u_char *p, u_int length, u_int caplen, 67 const u_char *esrc, const u_char *edst) 68 { 69 struct llc llc; 70 register u_short et; 71 #if 0 72 u_short control; 73 #endif 74 register int ret; 75 76 if (caplen < 3) { 77 (void)printf("[|llc]"); 78 default_print((u_char *)p, caplen); 79 return(0); 80 } 81 82 /* Watch out for possible alignment problems */ 83 memcpy((char *)&llc, (char *)p, min(caplen, sizeof(llc))); 84 85 if (llc.ssap == LLCSAP_GLOBAL && llc.dsap == LLCSAP_GLOBAL) { 86 ipx_print(p, length); 87 return (1); 88 } 89 #ifdef notyet 90 else if (p[0] == 0xf0 && p[1] == 0xf0) 91 netbios_print(p, length); 92 #endif 93 if (llc.ssap == LLCSAP_ISONS && llc.dsap == LLCSAP_ISONS 94 && llc.llcui == LLC_UI) { 95 isoclns_print(p + 3, length - 3, caplen - 3, esrc, edst); 96 return (1); 97 } 98 99 if (llc.ssap == LLCSAP_SNAP && llc.dsap == LLCSAP_SNAP 100 && llc.llcui == LLC_UI) { 101 if (caplen < sizeof(llc)) { 102 (void)printf("[|llc-snap]"); 103 default_print((u_char *)p, caplen); 104 return (0); 105 } 106 107 /* Cisco Discovery Protocol - SNAP & ether type 0x2000 */ 108 if (llc.ethertype[0] == 0x20 && llc.ethertype[1] == 0x00) { 109 cdp_print(p, length, caplen, esrc, edst); 110 return (1); 111 } 112 /* Shared Spanning Tree Protocol - SNAP & ether type 0x010b */ 113 if (llc.ethertype[0] == 0x01 && llc.ethertype[1] == 0x0b) { 114 stp_print(p, length); 115 return (1); 116 } 117 118 if (vflag) 119 (void)printf("snap %s ", protoid_string(llc.llcpi)); 120 121 caplen -= sizeof(llc); 122 length -= sizeof(llc); 123 p += sizeof(llc); 124 125 /* This is an encapsulated Ethernet packet */ 126 et = EXTRACT_16BITS(&llc.ethertype[0]); 127 128 /* 129 * Some protocols have special handling if they are 802.3 130 * SNAP encapsulated vs vers II encapsulated. Handle 131 * those special protocols here, and hand the rest to 132 * print-ether.c so we don't have to duplicate 133 * all that code here. 134 */ 135 switch (et) { 136 case ETHERTYPE_ATALK: 137 atalk_print(p, length); 138 ret = 1; 139 break; 140 default: 141 ret = ether_encap_print(et, p, length, caplen); 142 break; 143 } 144 145 if (ret) 146 return (ret); 147 } 148 149 if (llc.ssap == LLCSAP_8021D && llc.dsap == LLCSAP_8021D) { 150 stp_print(p, length); 151 return (1); 152 } 153 154 #if 0 155 if (llc.ssap == 0xf0 && llc.dsap == 0xf0) { 156 /* 157 * we don't actually have a full netbeui parser yet, but the 158 * smb parser can handle many smb-in-netbeui packets, which 159 * is very useful, so we call that 160 */ 161 162 /* 163 * Skip the DSAP and LSAP. 164 */ 165 p += 2; 166 length -= 2; 167 caplen -= 2; 168 169 /* 170 * OK, what type of LLC frame is this? The length 171 * of the control field depends on that - S or I 172 * frames have a two-byte control field, and U frames 173 * have a one-byte control field. 174 */ 175 if ((llc.llcu & LLC_U_FMT) == LLC_U_FMT) { 176 control = llc.llcu; 177 p += 1; 178 length -= 1; 179 caplen -= 1; 180 } else { 181 control = llc.llcis; 182 p += 2; 183 length -= 2; 184 caplen -= 2; 185 } 186 187 netbeui_print(control, p, p + min(caplen, length)); 188 return (1); 189 } 190 #endif 191 192 if ((llc.ssap & ~LLC_GSAP) == llc.dsap) { 193 if (eflag) 194 (void)printf("%s ", llcsap_string(llc.dsap)); 195 else 196 (void)printf("%s > %s %s ", 197 etheraddr_string(esrc), 198 etheraddr_string(edst), 199 llcsap_string(llc.dsap)); 200 } else { 201 if (eflag) 202 (void)printf("%s > %s ", 203 llcsap_string(llc.ssap & ~LLC_GSAP), 204 llcsap_string(llc.dsap)); 205 else 206 (void)printf("%s %s > %s %s ", 207 etheraddr_string(esrc), 208 llcsap_string(llc.ssap & ~LLC_GSAP), 209 etheraddr_string(edst), 210 llcsap_string(llc.dsap)); 211 } 212 213 if ((llc.llcu & LLC_U_FMT) == LLC_U_FMT) { 214 const char *m; 215 char f; 216 m = tok2str(cmd2str, "%02x", LLC_U_CMD(llc.llcu)); 217 switch ((llc.ssap & LLC_GSAP) | (llc.llcu & LLC_U_POLL)) { 218 case 0: f = 'C'; break; 219 case LLC_GSAP: f = 'R'; break; 220 case LLC_U_POLL: f = 'P'; break; 221 case LLC_GSAP|LLC_U_POLL: f = 'F'; break; 222 default: f = '?'; break; 223 } 224 225 printf("%s/%c", m, f); 226 227 if (caplen < 6) { 228 default_print_unaligned(p, caplen); 229 return (0); 230 } 231 p += 3; 232 length -= 3; 233 caplen -= 3; 234 235 if ((llc.llcu & ~LLC_U_POLL) == LLC_XID) { 236 if (*p == LLC_XID_FI) { 237 printf(": %02x %02x", p[1], p[2]); 238 p += 3; 239 length -= 3; 240 caplen -= 3; 241 } 242 } 243 244 #if 0 245 if (!strcmp(m,"ui") && f=='C') { 246 /* 247 * we don't have a proper ipx decoder yet, but there 248 * is a partial one in the smb code 249 */ 250 ipx_netbios_print(p,p+min(caplen,length)); 251 } 252 #endif 253 254 } else { 255 char f; 256 if (caplen < 4) { 257 default_print_unaligned(p, caplen); 258 return (0); 259 } 260 llc.llcis = ntohs(llc.llcis); 261 switch ((llc.ssap & LLC_GSAP) | (llc.llcu & LLC_U_POLL)) { 262 case 0: f = 'C'; break; 263 case LLC_GSAP: f = 'R'; break; 264 case LLC_U_POLL: f = 'P'; break; 265 case LLC_GSAP|LLC_U_POLL: f = 'F'; break; 266 default: f = '?'; break; 267 } 268 269 if ((llc.llcu & LLC_S_FMT) == LLC_S_FMT) { 270 static char *llc_s[] = { "rr", "rej", "rnr", "03" }; 271 (void)printf("%s (r=%d,%c)", 272 llc_s[LLC_S_CMD(llc.llcis)], 273 LLC_IS_NR(llc.llcis), 274 f); 275 } else { 276 (void)printf("I (s=%d,r=%d,%c)", 277 LLC_I_NS(llc.llcis), 278 LLC_IS_NR(llc.llcis), 279 f); 280 } 281 p += 4; 282 length -= 4; 283 caplen -= 4; 284 } 285 (void)printf(" len=%d", length); 286 return(1); 287 } 288