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 #include <sys/cdefs.h> 24 #ifndef lint 25 __RCSID("$NetBSD: print-zephyr.c,v 1.8 2017/09/08 14:01:13 christos Exp $"); 26 #endif 27 28 /* \summary: Zephyr printer */ 29 30 #ifdef HAVE_CONFIG_H 31 #include "config.h" 32 #endif 33 34 #include <netdissect-stdinc.h> 35 36 #include <stdio.h> 37 #include <string.h> 38 #include <stdlib.h> 39 40 #include "netdissect.h" 41 42 struct z_packet { 43 const char *version; 44 int numfields; 45 int kind; 46 const char *uid; 47 int port; 48 int auth; 49 int authlen; 50 const char *authdata; 51 const char *class; 52 const char *inst; 53 const char *opcode; 54 const char *sender; 55 const char *recipient; 56 const char *format; 57 int cksum; 58 int multi; 59 const char *multi_uid; 60 /* Other fields follow here.. */ 61 }; 62 63 enum z_packet_type { 64 Z_PACKET_UNSAFE = 0, 65 Z_PACKET_UNACKED, 66 Z_PACKET_ACKED, 67 Z_PACKET_HMACK, 68 Z_PACKET_HMCTL, 69 Z_PACKET_SERVACK, 70 Z_PACKET_SERVNAK, 71 Z_PACKET_CLIENTACK, 72 Z_PACKET_STAT 73 }; 74 75 static const struct tok z_types[] = { 76 { Z_PACKET_UNSAFE, "unsafe" }, 77 { Z_PACKET_UNACKED, "unacked" }, 78 { Z_PACKET_ACKED, "acked" }, 79 { Z_PACKET_HMACK, "hm-ack" }, 80 { Z_PACKET_HMCTL, "hm-ctl" }, 81 { Z_PACKET_SERVACK, "serv-ack" }, 82 { Z_PACKET_SERVNAK, "serv-nak" }, 83 { Z_PACKET_CLIENTACK, "client-ack" }, 84 { Z_PACKET_STAT, "stat" }, 85 { 0, NULL } 86 }; 87 88 static char z_buf[256]; 89 90 static const char * 91 parse_field(netdissect_options *ndo, const char **pptr, int *len, int *truncated) 92 { 93 const char *s; 94 95 /* Start of string */ 96 s = *pptr; 97 /* Scan for the NUL terminator */ 98 for (;;) { 99 if (*len == 0) { 100 /* Ran out of packet data without finding it */ 101 return NULL; 102 } 103 if (!ND_TTEST(**pptr)) { 104 /* Ran out of captured data without finding it */ 105 *truncated = 1; 106 return NULL; 107 } 108 if (**pptr == '\0') { 109 /* Found it */ 110 break; 111 } 112 /* Keep scanning */ 113 (*pptr)++; 114 (*len)--; 115 } 116 /* Skip the NUL terminator */ 117 (*pptr)++; 118 (*len)--; 119 return s; 120 } 121 122 static const char * 123 z_triple(const char *class, const char *inst, const char *recipient) 124 { 125 if (!*recipient) 126 recipient = "*"; 127 snprintf(z_buf, sizeof(z_buf), "<%s,%s,%s>", class, inst, recipient); 128 z_buf[sizeof(z_buf)-1] = '\0'; 129 return z_buf; 130 } 131 132 static const char * 133 str_to_lower(const char *string) 134 { 135 char *zb_string; 136 137 strncpy(z_buf, string, sizeof(z_buf)); 138 z_buf[sizeof(z_buf)-1] = '\0'; 139 140 zb_string = z_buf; 141 while (*zb_string) { 142 *zb_string = tolower((unsigned char)(*zb_string)); 143 zb_string++; 144 } 145 146 return z_buf; 147 } 148 149 void 150 zephyr_print(netdissect_options *ndo, const u_char *cp, int length) 151 { 152 struct z_packet z; 153 const char *parse = (const char *) cp; 154 int parselen = length; 155 const char *s; 156 int lose = 0; 157 int truncated = 0; 158 159 /* squelch compiler warnings */ 160 161 z.kind = 0; 162 z.class = 0; 163 z.inst = 0; 164 z.opcode = 0; 165 z.sender = 0; 166 z.recipient = 0; 167 168 memset(&z, 0, sizeof(z)); /* XXX gcc */ 169 170 #define PARSE_STRING \ 171 s = parse_field(ndo, &parse, &parselen, &truncated); \ 172 if (truncated) goto trunc; \ 173 if (!s) lose = 1; 174 175 #define PARSE_FIELD_INT(field) \ 176 PARSE_STRING \ 177 if (!lose) field = strtol(s, 0, 16); 178 179 #define PARSE_FIELD_STR(field) \ 180 PARSE_STRING \ 181 if (!lose) field = s; 182 183 PARSE_FIELD_STR(z.version); 184 if (lose) return; 185 if (strncmp(z.version, "ZEPH", 4)) 186 return; 187 188 PARSE_FIELD_INT(z.numfields); 189 PARSE_FIELD_INT(z.kind); 190 PARSE_FIELD_STR(z.uid); 191 PARSE_FIELD_INT(z.port); 192 PARSE_FIELD_INT(z.auth); 193 PARSE_FIELD_INT(z.authlen); 194 PARSE_FIELD_STR(z.authdata); 195 PARSE_FIELD_STR(z.class); 196 PARSE_FIELD_STR(z.inst); 197 PARSE_FIELD_STR(z.opcode); 198 PARSE_FIELD_STR(z.sender); 199 PARSE_FIELD_STR(z.recipient); 200 PARSE_FIELD_STR(z.format); 201 PARSE_FIELD_INT(z.cksum); 202 PARSE_FIELD_INT(z.multi); 203 PARSE_FIELD_STR(z.multi_uid); 204 205 if (lose) 206 goto trunc; 207 208 ND_PRINT((ndo, " zephyr")); 209 if (strncmp(z.version+4, "0.2", 3)) { 210 ND_PRINT((ndo, " v%s", z.version+4)); 211 return; 212 } 213 214 ND_PRINT((ndo, " %s", tok2str(z_types, "type %d", z.kind))); 215 if (z.kind == Z_PACKET_SERVACK) { 216 /* Initialization to silence warnings */ 217 const char *ackdata = NULL; 218 PARSE_FIELD_STR(ackdata); 219 if (!lose && strcmp(ackdata, "SENT")) 220 ND_PRINT((ndo, "/%s", str_to_lower(ackdata))); 221 } 222 if (*z.sender) ND_PRINT((ndo, " %s", z.sender)); 223 224 if (!strcmp(z.class, "USER_LOCATE")) { 225 if (!strcmp(z.opcode, "USER_HIDE")) 226 ND_PRINT((ndo, " hide")); 227 else if (!strcmp(z.opcode, "USER_UNHIDE")) 228 ND_PRINT((ndo, " unhide")); 229 else 230 ND_PRINT((ndo, " locate %s", z.inst)); 231 return; 232 } 233 234 if (!strcmp(z.class, "ZEPHYR_ADMIN")) { 235 ND_PRINT((ndo, " zephyr-admin %s", str_to_lower(z.opcode))); 236 return; 237 } 238 239 if (!strcmp(z.class, "ZEPHYR_CTL")) { 240 if (!strcmp(z.inst, "CLIENT")) { 241 if (!strcmp(z.opcode, "SUBSCRIBE") || 242 !strcmp(z.opcode, "SUBSCRIBE_NODEFS") || 243 !strcmp(z.opcode, "UNSUBSCRIBE")) { 244 245 ND_PRINT((ndo, " %ssub%s", strcmp(z.opcode, "SUBSCRIBE") ? "un" : "", 246 strcmp(z.opcode, "SUBSCRIBE_NODEFS") ? "" : 247 "-nodefs")); 248 if (z.kind != Z_PACKET_SERVACK) { 249 /* Initialization to silence warnings */ 250 const char *c = NULL, *i = NULL, *r = NULL; 251 PARSE_FIELD_STR(c); 252 PARSE_FIELD_STR(i); 253 PARSE_FIELD_STR(r); 254 if (!lose) ND_PRINT((ndo, " %s", z_triple(c, i, r))); 255 } 256 return; 257 } 258 259 if (!strcmp(z.opcode, "GIMME")) { 260 ND_PRINT((ndo, " ret")); 261 return; 262 } 263 264 if (!strcmp(z.opcode, "GIMMEDEFS")) { 265 ND_PRINT((ndo, " gimme-defs")); 266 return; 267 } 268 269 if (!strcmp(z.opcode, "CLEARSUB")) { 270 ND_PRINT((ndo, " clear-subs")); 271 return; 272 } 273 274 ND_PRINT((ndo, " %s", str_to_lower(z.opcode))); 275 return; 276 } 277 278 if (!strcmp(z.inst, "HM")) { 279 ND_PRINT((ndo, " %s", str_to_lower(z.opcode))); 280 return; 281 } 282 283 if (!strcmp(z.inst, "REALM")) { 284 if (!strcmp(z.opcode, "ADD_SUBSCRIBE")) 285 ND_PRINT((ndo, " realm add-subs")); 286 if (!strcmp(z.opcode, "REQ_SUBSCRIBE")) 287 ND_PRINT((ndo, " realm req-subs")); 288 if (!strcmp(z.opcode, "RLM_SUBSCRIBE")) 289 ND_PRINT((ndo, " realm rlm-sub")); 290 if (!strcmp(z.opcode, "RLM_UNSUBSCRIBE")) 291 ND_PRINT((ndo, " realm rlm-unsub")); 292 return; 293 } 294 } 295 296 if (!strcmp(z.class, "HM_CTL")) { 297 ND_PRINT((ndo, " hm_ctl %s", str_to_lower(z.inst))); 298 ND_PRINT((ndo, " %s", str_to_lower(z.opcode))); 299 return; 300 } 301 302 if (!strcmp(z.class, "HM_STAT")) { 303 if (!strcmp(z.inst, "HMST_CLIENT") && !strcmp(z.opcode, "GIMMESTATS")) { 304 ND_PRINT((ndo, " get-client-stats")); 305 return; 306 } 307 } 308 309 if (!strcmp(z.class, "WG_CTL")) { 310 ND_PRINT((ndo, " wg_ctl %s", str_to_lower(z.inst))); 311 ND_PRINT((ndo, " %s", str_to_lower(z.opcode))); 312 return; 313 } 314 315 if (!strcmp(z.class, "LOGIN")) { 316 if (!strcmp(z.opcode, "USER_FLUSH")) { 317 ND_PRINT((ndo, " flush_locs")); 318 return; 319 } 320 321 if (!strcmp(z.opcode, "NONE") || 322 !strcmp(z.opcode, "OPSTAFF") || 323 !strcmp(z.opcode, "REALM-VISIBLE") || 324 !strcmp(z.opcode, "REALM-ANNOUNCED") || 325 !strcmp(z.opcode, "NET-VISIBLE") || 326 !strcmp(z.opcode, "NET-ANNOUNCED")) { 327 ND_PRINT((ndo, " set-exposure %s", str_to_lower(z.opcode))); 328 return; 329 } 330 } 331 332 if (!*z.recipient) 333 z.recipient = "*"; 334 335 ND_PRINT((ndo, " to %s", z_triple(z.class, z.inst, z.recipient))); 336 if (*z.opcode) 337 ND_PRINT((ndo, " op %s", z.opcode)); 338 return; 339 340 trunc: 341 ND_PRINT((ndo, " [|zephyr] (%d)", length)); 342 return; 343 } 344