print-egp.c revision 1.1.1.7
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 /* \summary: Exterior Gateway Protocol (EGP) printer */ 22 23 /* specification: RFC 827 */ 24 25 #include <config.h> 26 27 #include "netdissect-stdinc.h" 28 29 #include "netdissect.h" 30 #include "addrtoname.h" 31 #include "extract.h" 32 33 struct egp_packet { 34 nd_uint8_t egp_version; 35 #define EGP_VERSION 2 36 nd_uint8_t egp_type; 37 #define EGPT_ACQUIRE 3 38 #define EGPT_REACH 5 39 #define EGPT_POLL 2 40 #define EGPT_UPDATE 1 41 #define EGPT_ERROR 8 42 nd_uint8_t egp_code; 43 #define EGPC_REQUEST 0 44 #define EGPC_CONFIRM 1 45 #define EGPC_REFUSE 2 46 #define EGPC_CEASE 3 47 #define EGPC_CEASEACK 4 48 #define EGPC_HELLO 0 49 #define EGPC_HEARDU 1 50 nd_uint8_t egp_status; 51 #define EGPS_UNSPEC 0 52 #define EGPS_ACTIVE 1 53 #define EGPS_PASSIVE 2 54 #define EGPS_NORES 3 55 #define EGPS_ADMIN 4 56 #define EGPS_GODOWN 5 57 #define EGPS_PARAM 6 58 #define EGPS_PROTO 7 59 #define EGPS_INDET 0 60 #define EGPS_UP 1 61 #define EGPS_DOWN 2 62 #define EGPS_UNSOL 0x80 63 nd_uint16_t egp_checksum; 64 nd_uint16_t egp_as; 65 nd_uint16_t egp_sequence; 66 union { 67 nd_uint16_t egpu_hello; 68 nd_uint8_t egpu_gws[2]; 69 nd_uint16_t egpu_reason; 70 #define EGPR_UNSPEC 0 71 #define EGPR_BADHEAD 1 72 #define EGPR_BADDATA 2 73 #define EGPR_NOREACH 3 74 #define EGPR_XSPOLL 4 75 #define EGPR_NORESP 5 76 #define EGPR_UVERSION 6 77 } egp_handg; 78 #define egp_hello egp_handg.egpu_hello 79 #define egp_intgw egp_handg.egpu_gws[0] 80 #define egp_extgw egp_handg.egpu_gws[1] 81 #define egp_reason egp_handg.egpu_reason 82 union { 83 nd_uint16_t egpu_poll; 84 nd_ipv4 egpu_sourcenet; 85 } egp_pands; 86 #define egp_poll egp_pands.egpu_poll 87 #define egp_sourcenet egp_pands.egpu_sourcenet 88 }; 89 90 static const char *egp_acquire_codes[] = { 91 "request", 92 "confirm", 93 "refuse", 94 "cease", 95 "cease_ack" 96 }; 97 98 static const char *egp_acquire_status[] = { 99 "unspecified", 100 "active_mode", 101 "passive_mode", 102 "insufficient_resources", 103 "administratively_prohibited", 104 "going_down", 105 "parameter_violation", 106 "protocol_violation" 107 }; 108 109 static const char *egp_reach_codes[] = { 110 "hello", 111 "i-h-u" 112 }; 113 114 static const char *egp_status_updown[] = { 115 "indeterminate", 116 "up", 117 "down" 118 }; 119 120 static const char *egp_reasons[] = { 121 "unspecified", 122 "bad_EGP_header_format", 123 "bad_EGP_data_field_format", 124 "reachability_info_unavailable", 125 "excessive_polling_rate", 126 "no_response", 127 "unsupported_version" 128 }; 129 130 static void 131 egpnr_print(netdissect_options *ndo, 132 const struct egp_packet *egp, u_int length) 133 { 134 const uint8_t *cp; 135 uint32_t addr; 136 uint32_t net; 137 u_int netlen; 138 u_int gateways, distances, networks; 139 u_int intgw, extgw, t_gateways; 140 const char *comma; 141 142 addr = GET_IPV4_TO_NETWORK_ORDER(egp->egp_sourcenet); 143 if (IN_CLASSA(addr)) { 144 net = addr & IN_CLASSA_NET; 145 netlen = 1; 146 } else if (IN_CLASSB(addr)) { 147 net = addr & IN_CLASSB_NET; 148 netlen = 2; 149 } else if (IN_CLASSC(addr)) { 150 net = addr & IN_CLASSC_NET; 151 netlen = 3; 152 } else { 153 net = 0; 154 netlen = 0; 155 } 156 cp = (const uint8_t *)(egp + 1); 157 length -= sizeof(*egp); 158 159 intgw = GET_U_1(egp->egp_intgw); 160 extgw = GET_U_1(egp->egp_extgw); 161 t_gateways = intgw + extgw; 162 for (gateways = 0; gateways < t_gateways; ++gateways) { 163 /* Pickup host part of gateway address */ 164 addr = 0; 165 if (length < 4 - netlen) 166 goto trunc; 167 ND_TCHECK_LEN(cp, 4 - netlen); 168 switch (netlen) { 169 170 case 1: 171 addr = GET_U_1(cp); 172 cp++; 173 /* fall through */ 174 case 2: 175 addr = (addr << 8) | GET_U_1(cp); 176 cp++; 177 /* fall through */ 178 case 3: 179 addr = (addr << 8) | GET_U_1(cp); 180 cp++; 181 break; 182 } 183 addr |= net; 184 length -= 4 - netlen; 185 if (length < 1) 186 goto trunc; 187 distances = GET_U_1(cp); 188 cp++; 189 length--; 190 ND_PRINT(" %s %s ", 191 gateways < intgw ? "int" : "ext", 192 ipaddr_string(ndo, (const u_char *)&addr)); /* local buffer, not packet data; don't use GET_IPADDR_STRING() */ 193 194 comma = ""; 195 ND_PRINT("("); 196 while (distances != 0) { 197 if (length < 2) 198 goto trunc; 199 ND_PRINT("%sd%u:", comma, GET_U_1(cp)); 200 cp++; 201 comma = ", "; 202 networks = GET_U_1(cp); 203 cp++; 204 length -= 2; 205 while (networks != 0) { 206 /* Pickup network number */ 207 if (length < 1) 208 goto trunc; 209 addr = ((uint32_t) GET_U_1(cp)) << 24; 210 cp++; 211 length--; 212 if (IN_CLASSB(addr)) { 213 if (length < 1) 214 goto trunc; 215 addr |= ((uint32_t) GET_U_1(cp)) << 16; 216 cp++; 217 length--; 218 } else if (!IN_CLASSA(addr)) { 219 if (length < 2) 220 goto trunc; 221 addr |= ((uint32_t) GET_U_1(cp)) << 16; 222 cp++; 223 addr |= ((uint32_t) GET_U_1(cp)) << 8; 224 cp++; 225 length -= 2; 226 } 227 ND_PRINT(" %s", ipaddr_string(ndo, (const u_char *)&addr)); /* local buffer, not packet data; don't use GET_IPADDR_STRING() */ 228 networks--; 229 } 230 distances--; 231 } 232 ND_PRINT(")"); 233 } 234 return; 235 trunc: 236 nd_print_trunc(ndo); 237 } 238 239 void 240 egp_print(netdissect_options *ndo, 241 const uint8_t *bp, u_int length) 242 { 243 const struct egp_packet *egp; 244 u_int version; 245 u_int type; 246 u_int code; 247 u_int status; 248 249 ndo->ndo_protocol = "egp"; 250 egp = (const struct egp_packet *)bp; 251 if (length < sizeof(*egp) || !ND_TTEST_SIZE(egp)) { 252 nd_print_trunc(ndo); 253 return; 254 } 255 256 version = GET_U_1(egp->egp_version); 257 if (!ndo->ndo_vflag) { 258 ND_PRINT("EGPv%u, AS %u, seq %u, length %u", 259 version, 260 GET_BE_U_2(egp->egp_as), 261 GET_BE_U_2(egp->egp_sequence), 262 length); 263 return; 264 } else 265 ND_PRINT("EGPv%u, length %u", 266 version, 267 length); 268 269 if (version != EGP_VERSION) { 270 ND_PRINT("[version %u]", version); 271 return; 272 } 273 274 type = GET_U_1(egp->egp_type); 275 code = GET_U_1(egp->egp_code); 276 status = GET_U_1(egp->egp_status); 277 278 switch (type) { 279 case EGPT_ACQUIRE: 280 ND_PRINT(" acquire"); 281 switch (code) { 282 case EGPC_REQUEST: 283 case EGPC_CONFIRM: 284 ND_PRINT(" %s", egp_acquire_codes[code]); 285 switch (status) { 286 case EGPS_UNSPEC: 287 case EGPS_ACTIVE: 288 case EGPS_PASSIVE: 289 ND_PRINT(" %s", egp_acquire_status[status]); 290 break; 291 292 default: 293 ND_PRINT(" [status %u]", status); 294 break; 295 } 296 ND_PRINT(" hello:%u poll:%u", 297 GET_BE_U_2(egp->egp_hello), 298 GET_BE_U_2(egp->egp_poll)); 299 break; 300 301 case EGPC_REFUSE: 302 case EGPC_CEASE: 303 case EGPC_CEASEACK: 304 ND_PRINT(" %s", egp_acquire_codes[code]); 305 switch (status ) { 306 case EGPS_UNSPEC: 307 case EGPS_NORES: 308 case EGPS_ADMIN: 309 case EGPS_GODOWN: 310 case EGPS_PARAM: 311 case EGPS_PROTO: 312 ND_PRINT(" %s", egp_acquire_status[status]); 313 break; 314 315 default: 316 ND_PRINT("[status %u]", status); 317 break; 318 } 319 break; 320 321 default: 322 ND_PRINT("[code %u]", code); 323 break; 324 } 325 break; 326 327 case EGPT_REACH: 328 switch (code) { 329 330 case EGPC_HELLO: 331 case EGPC_HEARDU: 332 ND_PRINT(" %s", egp_reach_codes[code]); 333 if (status <= EGPS_DOWN) 334 ND_PRINT(" state:%s", egp_status_updown[status]); 335 else 336 ND_PRINT(" [status %u]", status); 337 break; 338 339 default: 340 ND_PRINT("[reach code %u]", code); 341 break; 342 } 343 break; 344 345 case EGPT_POLL: 346 ND_PRINT(" poll"); 347 if (status <= EGPS_DOWN) 348 ND_PRINT(" state:%s", egp_status_updown[status]); 349 else 350 ND_PRINT(" [status %u]", status); 351 ND_PRINT(" net:%s", GET_IPADDR_STRING(egp->egp_sourcenet)); 352 break; 353 354 case EGPT_UPDATE: 355 ND_PRINT(" update"); 356 if (status & EGPS_UNSOL) { 357 status &= ~EGPS_UNSOL; 358 ND_PRINT(" unsolicited"); 359 } 360 if (status <= EGPS_DOWN) 361 ND_PRINT(" state:%s", egp_status_updown[status]); 362 else 363 ND_PRINT(" [status %u]", status); 364 ND_PRINT(" %s int %u ext %u", 365 GET_IPADDR_STRING(egp->egp_sourcenet), 366 GET_U_1(egp->egp_intgw), 367 GET_U_1(egp->egp_extgw)); 368 if (ndo->ndo_vflag) 369 egpnr_print(ndo, egp, length); 370 break; 371 372 case EGPT_ERROR: 373 ND_PRINT(" error"); 374 if (status <= EGPS_DOWN) 375 ND_PRINT(" state:%s", egp_status_updown[status]); 376 else 377 ND_PRINT(" [status %u]", status); 378 379 if (GET_BE_U_2(egp->egp_reason) <= EGPR_UVERSION) 380 ND_PRINT(" %s", 381 egp_reasons[GET_BE_U_2(egp->egp_reason)]); 382 else 383 ND_PRINT(" [reason %u]", GET_BE_U_2(egp->egp_reason)); 384 break; 385 386 default: 387 ND_PRINT("[type %u]", type); 388 break; 389 } 390 } 391
Indexes created Wed Aug 19 00:25:20 UTC 2026