print-egp.c revision 1.8
1 /* 2 * Copyright (c) 1991, 1992, 1993, 1994, 1995, 1996 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms are permitted 6 * provided that the above copyright notice and this paragraph are 7 * duplicated in all such forms and that any documentation, 8 * advertising materials, and other materials related to such 9 * distribution and use acknowledge that the software was developed 10 * by the University of California, Lawrence Berkeley Laboratory, 11 * Berkeley, CA. The name of the University may not be used to 12 * endorse or promote products derived from this software without 13 * specific prior written permission. 14 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 16 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 17 * 18 * Initial contribution from Jeff Honig (jch (at) MITCHELL.CIT.CORNELL.EDU). 19 */ 20 21 #include <sys/cdefs.h> 22 #ifndef lint 23 __RCSID("$NetBSD: print-egp.c,v 1.8 2024/09/02 16:15:31 christos Exp $"); 24 #endif 25 26 /* \summary: Exterior Gateway Protocol (EGP) printer */ 27 28 /* specification: RFC 827 */ 29 30 #include <config.h> 31 32 #include "netdissect-stdinc.h" 33 34 #include "netdissect.h" 35 #include "addrtoname.h" 36 #include "extract.h" 37 38 struct egp_packet { 39 nd_uint8_t egp_version; 40 #define EGP_VERSION 2 41 nd_uint8_t egp_type; 42 #define EGPT_ACQUIRE 3 43 #define EGPT_REACH 5 44 #define EGPT_POLL 2 45 #define EGPT_UPDATE 1 46 #define EGPT_ERROR 8 47 nd_uint8_t egp_code; 48 #define EGPC_REQUEST 0 49 #define EGPC_CONFIRM 1 50 #define EGPC_REFUSE 2 51 #define EGPC_CEASE 3 52 #define EGPC_CEASEACK 4 53 #define EGPC_HELLO 0 54 #define EGPC_HEARDU 1 55 nd_uint8_t egp_status; 56 #define EGPS_UNSPEC 0 57 #define EGPS_ACTIVE 1 58 #define EGPS_PASSIVE 2 59 #define EGPS_NORES 3 60 #define EGPS_ADMIN 4 61 #define EGPS_GODOWN 5 62 #define EGPS_PARAM 6 63 #define EGPS_PROTO 7 64 #define EGPS_INDET 0 65 #define EGPS_UP 1 66 #define EGPS_DOWN 2 67 #define EGPS_UNSOL 0x80 68 nd_uint16_t egp_checksum; 69 nd_uint16_t egp_as; 70 nd_uint16_t egp_sequence; 71 union { 72 nd_uint16_t egpu_hello; 73 nd_uint8_t egpu_gws[2]; 74 nd_uint16_t egpu_reason; 75 #define EGPR_UNSPEC 0 76 #define EGPR_BADHEAD 1 77 #define EGPR_BADDATA 2 78 #define EGPR_NOREACH 3 79 #define EGPR_XSPOLL 4 80 #define EGPR_NORESP 5 81 #define EGPR_UVERSION 6 82 } egp_handg; 83 #define egp_hello egp_handg.egpu_hello 84 #define egp_intgw egp_handg.egpu_gws[0] 85 #define egp_extgw egp_handg.egpu_gws[1] 86 #define egp_reason egp_handg.egpu_reason 87 union { 88 nd_uint16_t egpu_poll; 89 nd_ipv4 egpu_sourcenet; 90 } egp_pands; 91 #define egp_poll egp_pands.egpu_poll 92 #define egp_sourcenet egp_pands.egpu_sourcenet 93 }; 94 95 static const char *egp_acquire_codes[] = { 96 "request", 97 "confirm", 98 "refuse", 99 "cease", 100 "cease_ack" 101 }; 102 103 static const char *egp_acquire_status[] = { 104 "unspecified", 105 "active_mode", 106 "passive_mode", 107 "insufficient_resources", 108 "administratively_prohibited", 109 "going_down", 110 "parameter_violation", 111 "protocol_violation" 112 }; 113 114 static const char *egp_reach_codes[] = { 115 "hello", 116 "i-h-u" 117 }; 118 119 static const char *egp_status_updown[] = { 120 "indeterminate", 121 "up", 122 "down" 123 }; 124 125 static const char *egp_reasons[] = { 126 "unspecified", 127 "bad_EGP_header_format", 128 "bad_EGP_data_field_format", 129 "reachability_info_unavailable", 130 "excessive_polling_rate", 131 "no_response", 132 "unsupported_version" 133 }; 134 135 static void 136 egpnr_print(netdissect_options *ndo, 137 const struct egp_packet *egp, u_int length) 138 { 139 const uint8_t *cp; 140 uint32_t addr; 141 uint32_t net; 142 u_int netlen; 143 u_int gateways, distances, networks; 144 u_int intgw, extgw, t_gateways; 145 const char *comma; 146 147 addr = GET_IPV4_TO_NETWORK_ORDER(egp->egp_sourcenet); 148 if (IN_CLASSA(addr)) { 149 net = addr & IN_CLASSA_NET; 150 netlen = 1; 151 } else if (IN_CLASSB(addr)) { 152 net = addr & IN_CLASSB_NET; 153 netlen = 2; 154 } else if (IN_CLASSC(addr)) { 155 net = addr & IN_CLASSC_NET; 156 netlen = 3; 157 } else { 158 net = 0; 159 netlen = 0; 160 } 161 cp = (const uint8_t *)(egp + 1); 162 length -= sizeof(*egp); 163 164 intgw = GET_U_1(egp->egp_intgw); 165 extgw = GET_U_1(egp->egp_extgw); 166 t_gateways = intgw + extgw; 167 for (gateways = 0; gateways < t_gateways; ++gateways) { 168 /* Pickup host part of gateway address */ 169 addr = 0; 170 if (length < 4 - netlen) 171 goto trunc; 172 ND_TCHECK_LEN(cp, 4 - netlen); 173 switch (netlen) { 174 175 case 1: 176 addr = GET_U_1(cp); 177 cp++; 178 /* fall through */ 179 case 2: 180 addr = (addr << 8) | GET_U_1(cp); 181 cp++; 182 /* fall through */ 183 case 3: 184 addr = (addr << 8) | GET_U_1(cp); 185 cp++; 186 break; 187 } 188 addr |= net; 189 length -= 4 - netlen; 190 if (length < 1) 191 goto trunc; 192 distances = GET_U_1(cp); 193 cp++; 194 length--; 195 ND_PRINT(" %s %s ", 196 gateways < intgw ? "int" : "ext", 197 ipaddr_string(ndo, (const u_char *)&addr)); /* local buffer, not packet data; don't use GET_IPADDR_STRING() */ 198 199 comma = ""; 200 ND_PRINT("("); 201 while (distances != 0) { 202 if (length < 2) 203 goto trunc; 204 ND_PRINT("%sd%u:", comma, GET_U_1(cp)); 205 cp++; 206 comma = ", "; 207 networks = GET_U_1(cp); 208 cp++; 209 length -= 2; 210 while (networks != 0) { 211 /* Pickup network number */ 212 if (length < 1) 213 goto trunc; 214 addr = ((uint32_t) GET_U_1(cp)) << 24; 215 cp++; 216 length--; 217 if (IN_CLASSB(addr)) { 218 if (length < 1) 219 goto trunc; 220 addr |= ((uint32_t) GET_U_1(cp)) << 16; 221 cp++; 222 length--; 223 } else if (!IN_CLASSA(addr)) { 224 if (length < 2) 225 goto trunc; 226 addr |= ((uint32_t) GET_U_1(cp)) << 16; 227 cp++; 228 addr |= ((uint32_t) GET_U_1(cp)) << 8; 229 cp++; 230 length -= 2; 231 } 232 ND_PRINT(" %s", ipaddr_string(ndo, (const u_char *)&addr)); /* local buffer, not packet data; don't use GET_IPADDR_STRING() */ 233 networks--; 234 } 235 distances--; 236 } 237 ND_PRINT(")"); 238 } 239 return; 240 trunc: 241 nd_print_trunc(ndo); 242 } 243 244 void 245 egp_print(netdissect_options *ndo, 246 const uint8_t *bp, u_int length) 247 { 248 const struct egp_packet *egp; 249 u_int version; 250 u_int type; 251 u_int code; 252 u_int status; 253 254 ndo->ndo_protocol = "egp"; 255 egp = (const struct egp_packet *)bp; 256 if (length < sizeof(*egp) || !ND_TTEST_SIZE(egp)) { 257 nd_print_trunc(ndo); 258 return; 259 } 260 261 version = GET_U_1(egp->egp_version); 262 if (!ndo->ndo_vflag) { 263 ND_PRINT("EGPv%u, AS %u, seq %u, length %u", 264 version, 265 GET_BE_U_2(egp->egp_as), 266 GET_BE_U_2(egp->egp_sequence), 267 length); 268 return; 269 } else 270 ND_PRINT("EGPv%u, length %u", 271 version, 272 length); 273 274 if (version != EGP_VERSION) { 275 ND_PRINT("[version %u]", version); 276 return; 277 } 278 279 type = GET_U_1(egp->egp_type); 280 code = GET_U_1(egp->egp_code); 281 status = GET_U_1(egp->egp_status); 282 283 switch (type) { 284 case EGPT_ACQUIRE: 285 ND_PRINT(" acquire"); 286 switch (code) { 287 case EGPC_REQUEST: 288 case EGPC_CONFIRM: 289 ND_PRINT(" %s", egp_acquire_codes[code]); 290 switch (status) { 291 case EGPS_UNSPEC: 292 case EGPS_ACTIVE: 293 case EGPS_PASSIVE: 294 ND_PRINT(" %s", egp_acquire_status[status]); 295 break; 296 297 default: 298 ND_PRINT(" [status %u]", status); 299 break; 300 } 301 ND_PRINT(" hello:%u poll:%u", 302 GET_BE_U_2(egp->egp_hello), 303 GET_BE_U_2(egp->egp_poll)); 304 break; 305 306 case EGPC_REFUSE: 307 case EGPC_CEASE: 308 case EGPC_CEASEACK: 309 ND_PRINT(" %s", egp_acquire_codes[code]); 310 switch (status ) { 311 case EGPS_UNSPEC: 312 case EGPS_NORES: 313 case EGPS_ADMIN: 314 case EGPS_GODOWN: 315 case EGPS_PARAM: 316 case EGPS_PROTO: 317 ND_PRINT(" %s", egp_acquire_status[status]); 318 break; 319 320 default: 321 ND_PRINT("[status %u]", status); 322 break; 323 } 324 break; 325 326 default: 327 ND_PRINT("[code %u]", code); 328 break; 329 } 330 break; 331 332 case EGPT_REACH: 333 switch (code) { 334 335 case EGPC_HELLO: 336 case EGPC_HEARDU: 337 ND_PRINT(" %s", egp_reach_codes[code]); 338 if (status <= EGPS_DOWN) 339 ND_PRINT(" state:%s", egp_status_updown[status]); 340 else 341 ND_PRINT(" [status %u]", status); 342 break; 343 344 default: 345 ND_PRINT("[reach code %u]", code); 346 break; 347 } 348 break; 349 350 case EGPT_POLL: 351 ND_PRINT(" poll"); 352 if (status <= EGPS_DOWN) 353 ND_PRINT(" state:%s", egp_status_updown[status]); 354 else 355 ND_PRINT(" [status %u]", status); 356 ND_PRINT(" net:%s", GET_IPADDR_STRING(egp->egp_sourcenet)); 357 break; 358 359 case EGPT_UPDATE: 360 ND_PRINT(" update"); 361 if (status & EGPS_UNSOL) { 362 status &= ~EGPS_UNSOL; 363 ND_PRINT(" unsolicited"); 364 } 365 if (status <= EGPS_DOWN) 366 ND_PRINT(" state:%s", egp_status_updown[status]); 367 else 368 ND_PRINT(" [status %u]", status); 369 ND_PRINT(" %s int %u ext %u", 370 GET_IPADDR_STRING(egp->egp_sourcenet), 371 GET_U_1(egp->egp_intgw), 372 GET_U_1(egp->egp_extgw)); 373 if (ndo->ndo_vflag) 374 egpnr_print(ndo, egp, length); 375 break; 376 377 case EGPT_ERROR: 378 ND_PRINT(" error"); 379 if (status <= EGPS_DOWN) 380 ND_PRINT(" state:%s", egp_status_updown[status]); 381 else 382 ND_PRINT(" [status %u]", status); 383 384 if (GET_BE_U_2(egp->egp_reason) <= EGPR_UVERSION) 385 ND_PRINT(" %s", 386 egp_reasons[GET_BE_U_2(egp->egp_reason)]); 387 else 388 ND_PRINT(" [reason %u]", GET_BE_U_2(egp->egp_reason)); 389 break; 390 391 default: 392 ND_PRINT("[type %u]", type); 393 break; 394 } 395 } 396
Indexes created Wed Aug 19 00:25:20 UTC 2026