1 /* 2 * Decode and print Zephyr packets. 3 * 4 * http://web.mit.edu/zephyr/doc/protocol 5 * 6 * Copyright (c) 2001 Nickolai Zeldovich <kolya@MIT.EDU> 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that: (1) source code 11 * distributions retain the above copyright notice and this paragraph 12 * in its entirety, and (2) distributions including binary code include 13 * the above copyright notice and this paragraph in its entirety in 14 * the documentation or other materials provided with the distribution. 15 * The name of the author(s) may not be used to endorse or promote 16 * products derived from this software without specific prior written 17 * permission. THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY 18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 20 * PURPOSE. 21 */ 22 23 /* \summary: Zephyr printer */ 24 25 #ifdef HAVE_CONFIG_H 26 #include "config.h" 27 #endif 28 29 #include <netdissect-stdinc.h> 30 31 #include <stdio.h> 32 #include <string.h> 33 #include <stdlib.h> 34 35 #include "netdissect.h" 36 37 struct z_packet { 38 const char *version; 39 int numfields; 40 int kind; 41 const char *uid; 42 int port; 43 int auth; 44 int authlen; 45 const char *authdata; 46 const char *class; 47 const char *inst; 48 const char *opcode; 49 const char *sender; 50 const char *recipient; 51 const char *format; 52 int cksum; 53 int multi; 54 const char *multi_uid; 55 /* Other fields follow here.. */ 56 }; 57 58 enum z_packet_type { 59 Z_PACKET_UNSAFE = 0, 60 Z_PACKET_UNACKED, 61 Z_PACKET_ACKED, 62 Z_PACKET_HMACK, 63 Z_PACKET_HMCTL, 64 Z_PACKET_SERVACK, 65 Z_PACKET_SERVNAK, 66 Z_PACKET_CLIENTACK, 67 Z_PACKET_STAT 68 }; 69 70 static const struct tok z_types[] = { 71 { Z_PACKET_UNSAFE, "unsafe" }, 72 { Z_PACKET_UNACKED, "unacked" }, 73 { Z_PACKET_ACKED, "acked" }, 74 { Z_PACKET_HMACK, "hm-ack" }, 75 { Z_PACKET_HMCTL, "hm-ctl" }, 76 { Z_PACKET_SERVACK, "serv-ack" }, 77 { Z_PACKET_SERVNAK, "serv-nak" }, 78 { Z_PACKET_CLIENTACK, "client-ack" }, 79 { Z_PACKET_STAT, "stat" }, 80 { 0, NULL } 81 }; 82 83 static char z_buf[256]; 84 85 static const char * 86 parse_field(netdissect_options *ndo, const char **pptr, int *len, int *truncated) 87 { 88 const char *s; 89 90 /* Start of string */ 91 s = *pptr; 92 /* Scan for the NUL terminator */ 93 for (;;) { 94 if (*len == 0) { 95 /* Ran out of packet data without finding it */ 96 return NULL; 97 } 98 if (!ND_TTEST(**pptr)) { 99 /* Ran out of captured data without finding it */ 100 *truncated = 1; 101 return NULL; 102 } 103 if (**pptr == '\0') { 104 /* Found it */ 105 break; 106 } 107 /* Keep scanning */ 108 (*pptr)++; 109 (*len)--; 110 } 111 /* Skip the NUL terminator */ 112 (*pptr)++; 113 (*len)--; 114 return s; 115 } 116 117 static const char * 118 z_triple(const char *class, const char *inst, const char *recipient) 119 { 120 if (!*recipient) 121 recipient = "*"; 122 snprintf(z_buf, sizeof(z_buf), "<%s,%s,%s>", class, inst, recipient); 123 z_buf[sizeof(z_buf)-1] = '\0'; 124 return z_buf; 125 } 126 127 static const char * 128 str_to_lower(const char *string) 129 { 130 char *zb_string; 131 132 strncpy(z_buf, string, sizeof(z_buf)); 133 z_buf[sizeof(z_buf)-1] = '\0'; 134 135 zb_string = z_buf; 136 while (*zb_string) { 137 *zb_string = tolower((unsigned char)(*zb_string)); 138 zb_string++; 139 } 140 141 return z_buf; 142 } 143 144 void 145 zephyr_print(netdissect_options *ndo, const u_char *cp, int length) 146 { 147 struct z_packet z; 148 const char *parse = (const char *) cp; 149 int parselen = length; 150 const char *s; 151 int lose = 0; 152 int truncated = 0; 153 154 /* squelch compiler warnings */ 155 156 z.kind = 0; 157 z.class = 0; 158 z.inst = 0; 159 z.opcode = 0; 160 z.sender = 0; 161 z.recipient = 0; 162 163 #define PARSE_STRING \ 164 s = parse_field(ndo, &parse, &parselen, &truncated); \ 165 if (truncated) goto trunc; \ 166 if (!s) lose = 1; 167 168 #define PARSE_FIELD_INT(field) \ 169 PARSE_STRING \ 170 if (!lose) field = strtol(s, 0, 16); 171 172 #define PARSE_FIELD_STR(field) \ 173 PARSE_STRING \ 174 if (!lose) field = s; 175 176 PARSE_FIELD_STR(z.version); 177 if (lose) return; 178 if (strncmp(z.version, "ZEPH", 4)) 179 return; 180 181 PARSE_FIELD_INT(z.numfields); 182 PARSE_FIELD_INT(z.kind); 183 PARSE_FIELD_STR(z.uid); 184 PARSE_FIELD_INT(z.port); 185 PARSE_FIELD_INT(z.auth); 186 PARSE_FIELD_INT(z.authlen); 187 PARSE_FIELD_STR(z.authdata); 188 PARSE_FIELD_STR(z.class); 189 PARSE_FIELD_STR(z.inst); 190 PARSE_FIELD_STR(z.opcode); 191 PARSE_FIELD_STR(z.sender); 192 PARSE_FIELD_STR(z.recipient); 193 PARSE_FIELD_STR(z.format); 194 PARSE_FIELD_INT(z.cksum); 195 PARSE_FIELD_INT(z.multi); 196 PARSE_FIELD_STR(z.multi_uid); 197 198 if (lose) 199 goto trunc; 200 201 ND_PRINT((ndo, " zephyr")); 202 if (strncmp(z.version+4, "0.2", 3)) { 203 ND_PRINT((ndo, " v%s", z.version+4)); 204 return; 205 } 206 207 ND_PRINT((ndo, " %s", tok2str(z_types, "type %d", z.kind))); 208 if (z.kind == Z_PACKET_SERVACK) { 209 /* Initialization to silence warnings */ 210 const char *ackdata = NULL; 211 PARSE_FIELD_STR(ackdata); 212 if (!lose && strcmp(ackdata, "SENT")) 213 ND_PRINT((ndo, "/%s", str_to_lower(ackdata))); 214 } 215 if (*z.sender) ND_PRINT((ndo, " %s", z.sender)); 216 217 if (!strcmp(z.class, "USER_LOCATE")) { 218 if (!strcmp(z.opcode, "USER_HIDE")) 219 ND_PRINT((ndo, " hide")); 220 else if (!strcmp(z.opcode, "USER_UNHIDE")) 221 ND_PRINT((ndo, " unhide")); 222 else 223 ND_PRINT((ndo, " locate %s", z.inst)); 224 return; 225 } 226 227 if (!strcmp(z.class, "ZEPHYR_ADMIN")) { 228 ND_PRINT((ndo, " zephyr-admin %s", str_to_lower(z.opcode))); 229 return; 230 } 231 232 if (!strcmp(z.class, "ZEPHYR_CTL")) { 233 if (!strcmp(z.inst, "CLIENT")) { 234 if (!strcmp(z.opcode, "SUBSCRIBE") || 235 !strcmp(z.opcode, "SUBSCRIBE_NODEFS") || 236 !strcmp(z.opcode, "UNSUBSCRIBE")) { 237 238 ND_PRINT((ndo, " %ssub%s", strcmp(z.opcode, "SUBSCRIBE") ? "un" : "", 239 strcmp(z.opcode, "SUBSCRIBE_NODEFS") ? "" : 240 "-nodefs")); 241 if (z.kind != Z_PACKET_SERVACK) { 242 /* Initialization to silence warnings */ 243 const char *c = NULL, *i = NULL, *r = NULL; 244 PARSE_FIELD_STR(c); 245 PARSE_FIELD_STR(i); 246 PARSE_FIELD_STR(r); 247 if (!lose) ND_PRINT((ndo, " %s", z_triple(c, i, r))); 248 } 249 return; 250 } 251 252 if (!strcmp(z.opcode, "GIMME")) { 253 ND_PRINT((ndo, " ret")); 254 return; 255 } 256 257 if (!strcmp(z.opcode, "GIMMEDEFS")) { 258 ND_PRINT((ndo, " gimme-defs")); 259 return; 260 } 261 262 if (!strcmp(z.opcode, "CLEARSUB")) { 263 ND_PRINT((ndo, " clear-subs")); 264 return; 265 } 266 267 ND_PRINT((ndo, " %s", str_to_lower(z.opcode))); 268 return; 269 } 270 271 if (!strcmp(z.inst, "HM")) { 272 ND_PRINT((ndo, " %s", str_to_lower(z.opcode))); 273 return; 274 } 275 276 if (!strcmp(z.inst, "REALM")) { 277 if (!strcmp(z.opcode, "ADD_SUBSCRIBE")) 278 ND_PRINT((ndo, " realm add-subs")); 279 if (!strcmp(z.opcode, "REQ_SUBSCRIBE")) 280 ND_PRINT((ndo, " realm req-subs")); 281 if (!strcmp(z.opcode, "RLM_SUBSCRIBE")) 282 ND_PRINT((ndo, " realm rlm-sub")); 283 if (!strcmp(z.opcode, "RLM_UNSUBSCRIBE")) 284 ND_PRINT((ndo, " realm rlm-unsub")); 285 return; 286 } 287 } 288 289 if (!strcmp(z.class, "HM_CTL")) { 290 ND_PRINT((ndo, " hm_ctl %s", str_to_lower(z.inst))); 291 ND_PRINT((ndo, " %s", str_to_lower(z.opcode))); 292 return; 293 } 294 295 if (!strcmp(z.class, "HM_STAT")) { 296 if (!strcmp(z.inst, "HMST_CLIENT") && !strcmp(z.opcode, "GIMMESTATS")) { 297 ND_PRINT((ndo, " get-client-stats")); 298 return; 299 } 300 } 301 302 if (!strcmp(z.class, "WG_CTL")) { 303 ND_PRINT((ndo, " wg_ctl %s", str_to_lower(z.inst))); 304 ND_PRINT((ndo, " %s", str_to_lower(z.opcode))); 305 return; 306 } 307 308 if (!strcmp(z.class, "LOGIN")) { 309 if (!strcmp(z.opcode, "USER_FLUSH")) { 310 ND_PRINT((ndo, " flush_locs")); 311 return; 312 } 313 314 if (!strcmp(z.opcode, "NONE") || 315 !strcmp(z.opcode, "OPSTAFF") || 316 !strcmp(z.opcode, "REALM-VISIBLE") || 317 !strcmp(z.opcode, "REALM-ANNOUNCED") || 318 !strcmp(z.opcode, "NET-VISIBLE") || 319 !strcmp(z.opcode, "NET-ANNOUNCED")) { 320 ND_PRINT((ndo, " set-exposure %s", str_to_lower(z.opcode))); 321 return; 322 } 323 } 324 325 if (!*z.recipient) 326 z.recipient = "*"; 327 328 ND_PRINT((ndo, " to %s", z_triple(z.class, z.inst, z.recipient))); 329 if (*z.opcode) 330 ND_PRINT((ndo, " op %s", z.opcode)); 331 return; 332 333 trunc: 334 ND_PRINT((ndo, " [|zephyr] (%d)", length)); 335 return; 336 } 337