print-egp.c revision 1.7
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 1.7 2023/08/17 20:19:40 christos Exp $"); 24 #endif 25 26 /* \summary: Exterior Gateway Protocol (EGP) printer */ 27 28 /* specification: RFC 827 */ 29 30 #ifdef HAVE_CONFIG_H 31 #include <config.h> 32 #endif 33 34 #include "netdissect-stdinc.h" 35 36 #include "netdissect.h" 37 #include "addrtoname.h" 38 #include "extract.h" 39 40 struct egp_packet { 41 nd_uint8_t egp_version; 42 #define EGP_VERSION 2 43 nd_uint8_t egp_type; 44 #define EGPT_ACQUIRE 3 45 #define EGPT_REACH 5 46 #define EGPT_POLL 2 47 #define EGPT_UPDATE 1 48 #define EGPT_ERROR 8 49 nd_uint8_t egp_code; 50 #define EGPC_REQUEST 0 51 #define EGPC_CONFIRM 1 52 #define EGPC_REFUSE 2 53 #define EGPC_CEASE 3 54 #define EGPC_CEASEACK 4 55 #define EGPC_HELLO 0 56 #define EGPC_HEARDU 1 57 nd_uint8_t egp_status; 58 #define EGPS_UNSPEC 0 59 #define EGPS_ACTIVE 1 60 #define EGPS_PASSIVE 2 61 #define EGPS_NORES 3 62 #define EGPS_ADMIN 4 63 #define EGPS_GODOWN 5 64 #define EGPS_PARAM 6 65 #define EGPS_PROTO 7 66 #define EGPS_INDET 0 67 #define EGPS_UP 1 68 #define EGPS_DOWN 2 69 #define EGPS_UNSOL 0x80 70 nd_uint16_t egp_checksum; 71 nd_uint16_t egp_as; 72 nd_uint16_t egp_sequence; 73 union { 74 nd_uint16_t egpu_hello; 75 nd_uint8_t egpu_gws[2]; 76 nd_uint16_t egpu_reason; 77 #define EGPR_UNSPEC 0 78 #define EGPR_BADHEAD 1 79 #define EGPR_BADDATA 2 80 #define EGPR_NOREACH 3 81 #define EGPR_XSPOLL 4 82 #define EGPR_NORESP 5 83 #define EGPR_UVERSION 6 84 } egp_handg; 85 #define egp_hello egp_handg.egpu_hello 86 #define egp_intgw egp_handg.egpu_gws[0] 87 #define egp_extgw egp_handg.egpu_gws[1] 88 #define egp_reason egp_handg.egpu_reason 89 union { 90 nd_uint16_t egpu_poll; 91 nd_ipv4 egpu_sourcenet; 92 } egp_pands; 93 #define egp_poll egp_pands.egpu_poll 94 #define egp_sourcenet egp_pands.egpu_sourcenet 95 }; 96 97 static const char *egp_acquire_codes[] = { 98 "request", 99 "confirm", 100 "refuse", 101 "cease", 102 "cease_ack" 103 }; 104 105 static const char *egp_acquire_status[] = { 106 "unspecified", 107 "active_mode", 108 "passive_mode", 109 "insufficient_resources", 110 "administratively_prohibited", 111 "going_down", 112 "parameter_violation", 113 "protocol_violation" 114 }; 115 116 static const char *egp_reach_codes[] = { 117 "hello", 118 "i-h-u" 119 }; 120 121 static const char *egp_status_updown[] = { 122 "indeterminate", 123 "up", 124 "down" 125 }; 126 127 static const char *egp_reasons[] = { 128 "unspecified", 129 "bad_EGP_header_format", 130 "bad_EGP_data_field_format", 131 "reachability_info_unavailable", 132 "excessive_polling_rate", 133 "no_response", 134 "unsupported_version" 135 }; 136 137 static void 138 egpnr_print(netdissect_options *ndo, 139 const struct egp_packet *egp, u_int length) 140 { 141 const uint8_t *cp; 142 uint32_t addr; 143 uint32_t net; 144 u_int netlen; 145 u_int gateways, distances, networks; 146 u_int intgw, extgw, t_gateways; 147 const char *comma; 148 149 addr = GET_IPV4_TO_NETWORK_ORDER(egp->egp_sourcenet); 150 if (IN_CLASSA(addr)) { 151 net = addr & IN_CLASSA_NET; 152 netlen = 1; 153 } else if (IN_CLASSB(addr)) { 154 net = addr & IN_CLASSB_NET; 155 netlen = 2; 156 } else if (IN_CLASSC(addr)) { 157 net = addr & IN_CLASSC_NET; 158 netlen = 3; 159 } else { 160 net = 0; 161 netlen = 0; 162 } 163 cp = (const uint8_t *)(egp + 1); 164 length -= sizeof(*egp); 165 166 intgw = GET_U_1(egp->egp_intgw); 167 extgw = GET_U_1(egp->egp_extgw); 168 t_gateways = intgw + extgw; 169 for (gateways = 0; gateways < t_gateways; ++gateways) { 170 /* Pickup host part of gateway address */ 171 addr = 0; 172 if (length < 4 - netlen) 173 goto trunc; 174 ND_TCHECK_LEN(cp, 4 - netlen); 175 switch (netlen) { 176 177 case 1: 178 addr = GET_U_1(cp); 179 cp++; 180 /* fall through */ 181 case 2: 182 addr = (addr << 8) | GET_U_1(cp); 183 cp++; 184 /* fall through */ 185 case 3: 186 addr = (addr << 8) | GET_U_1(cp); 187 cp++; 188 break; 189 } 190 addr |= net; 191 length -= 4 - netlen; 192 if (length < 1) 193 goto trunc; 194 distances = GET_U_1(cp); 195 cp++; 196 length--; 197 ND_PRINT(" %s %s ", 198 gateways < intgw ? "int" : "ext", 199 ipaddr_string(ndo, (const u_char *)&addr)); /* local buffer, not packet data; don't use GET_IPADDR_STRING() */ 200 201 comma = ""; 202 ND_PRINT("("); 203 while (distances != 0) { 204 if (length < 2) 205 goto trunc; 206 ND_PRINT("%sd%u:", comma, GET_U_1(cp)); 207 cp++; 208 comma = ", "; 209 networks = GET_U_1(cp); 210 cp++; 211 length -= 2; 212 while (networks != 0) { 213 /* Pickup network number */ 214 if (length < 1) 215 goto trunc; 216 addr = ((uint32_t) GET_U_1(cp)) << 24; 217 cp++; 218 length--; 219 if (IN_CLASSB(addr)) { 220 if (length < 1) 221 goto trunc; 222 addr |= ((uint32_t) GET_U_1(cp)) << 16; 223 cp++; 224 length--; 225 } else if (!IN_CLASSA(addr)) { 226 if (length < 2) 227 goto trunc; 228 addr |= ((uint32_t) GET_U_1(cp)) << 16; 229 cp++; 230 addr |= ((uint32_t) GET_U_1(cp)) << 8; 231 cp++; 232 length -= 2; 233 } 234 ND_PRINT(" %s", ipaddr_string(ndo, (const u_char *)&addr)); /* local buffer, not packet data; don't use GET_IPADDR_STRING() */ 235 networks--; 236 } 237 distances--; 238 } 239 ND_PRINT(")"); 240 } 241 return; 242 trunc: 243 nd_print_trunc(ndo); 244 } 245 246 void 247 egp_print(netdissect_options *ndo, 248 const uint8_t *bp, u_int length) 249 { 250 const struct egp_packet *egp; 251 u_int version; 252 u_int type; 253 u_int code; 254 u_int status; 255 256 ndo->ndo_protocol = "egp"; 257 egp = (const struct egp_packet *)bp; 258 if (length < sizeof(*egp) || !ND_TTEST_SIZE(egp)) { 259 nd_print_trunc(ndo); 260 return; 261 } 262 263 version = GET_U_1(egp->egp_version); 264 if (!ndo->ndo_vflag) { 265 ND_PRINT("EGPv%u, AS %u, seq %u, length %u", 266 version, 267 GET_BE_U_2(egp->egp_as), 268 GET_BE_U_2(egp->egp_sequence), 269 length); 270 return; 271 } else 272 ND_PRINT("EGPv%u, length %u", 273 version, 274 length); 275 276 if (version != EGP_VERSION) { 277 ND_PRINT("[version %u]", version); 278 return; 279 } 280 281 type = GET_U_1(egp->egp_type); 282 code = GET_U_1(egp->egp_code); 283 status = GET_U_1(egp->egp_status); 284 285 switch (type) { 286 case EGPT_ACQUIRE: 287 ND_PRINT(" acquire"); 288 switch (code) { 289 case EGPC_REQUEST: 290 case EGPC_CONFIRM: 291 ND_PRINT(" %s", egp_acquire_codes[code]); 292 switch (status) { 293 case EGPS_UNSPEC: 294 case EGPS_ACTIVE: 295 case EGPS_PASSIVE: 296 ND_PRINT(" %s", egp_acquire_status[status]); 297 break; 298 299 default: 300 ND_PRINT(" [status %u]", status); 301 break; 302 } 303 ND_PRINT(" hello:%u poll:%u", 304 GET_BE_U_2(egp->egp_hello), 305 GET_BE_U_2(egp->egp_poll)); 306 break; 307 308 case EGPC_REFUSE: 309 case EGPC_CEASE: 310 case EGPC_CEASEACK: 311 ND_PRINT(" %s", egp_acquire_codes[code]); 312 switch (status ) { 313 case EGPS_UNSPEC: 314 case EGPS_NORES: 315 case EGPS_ADMIN: 316 case EGPS_GODOWN: 317 case EGPS_PARAM: 318 case EGPS_PROTO: 319 ND_PRINT(" %s", egp_acquire_status[status]); 320 break; 321 322 default: 323 ND_PRINT("[status %u]", status); 324 break; 325 } 326 break; 327 328 default: 329 ND_PRINT("[code %u]", code); 330 break; 331 } 332 break; 333 334 case EGPT_REACH: 335 switch (code) { 336 337 case EGPC_HELLO: 338 case EGPC_HEARDU: 339 ND_PRINT(" %s", egp_reach_codes[code]); 340 if (status <= EGPS_DOWN) 341 ND_PRINT(" state:%s", egp_status_updown[status]); 342 else 343 ND_PRINT(" [status %u]", status); 344 break; 345 346 default: 347 ND_PRINT("[reach code %u]", code); 348 break; 349 } 350 break; 351 352 case EGPT_POLL: 353 ND_PRINT(" poll"); 354 if (status <= EGPS_DOWN) 355 ND_PRINT(" state:%s", egp_status_updown[status]); 356 else 357 ND_PRINT(" [status %u]", status); 358 ND_PRINT(" net:%s", GET_IPADDR_STRING(egp->egp_sourcenet)); 359 break; 360 361 case EGPT_UPDATE: 362 ND_PRINT(" update"); 363 if (status & EGPS_UNSOL) { 364 status &= ~EGPS_UNSOL; 365 ND_PRINT(" unsolicited"); 366 } 367 if (status <= EGPS_DOWN) 368 ND_PRINT(" state:%s", egp_status_updown[status]); 369 else 370 ND_PRINT(" [status %u]", status); 371 ND_PRINT(" %s int %u ext %u", 372 GET_IPADDR_STRING(egp->egp_sourcenet), 373 GET_U_1(egp->egp_intgw), 374 GET_U_1(egp->egp_extgw)); 375 if (ndo->ndo_vflag) 376 egpnr_print(ndo, egp, length); 377 break; 378 379 case EGPT_ERROR: 380 ND_PRINT(" error"); 381 if (status <= EGPS_DOWN) 382 ND_PRINT(" state:%s", egp_status_updown[status]); 383 else 384 ND_PRINT(" [status %u]", status); 385 386 if (GET_BE_U_2(egp->egp_reason) <= EGPR_UVERSION) 387 ND_PRINT(" %s", 388 egp_reasons[GET_BE_U_2(egp->egp_reason)]); 389 else 390 ND_PRINT(" [reason %u]", GET_BE_U_2(egp->egp_reason)); 391 break; 392 393 default: 394 ND_PRINT("[type %u]", type); 395 break; 396 } 397 } 398
Indexes created Wed Aug 19 00:25:20 UTC 2026