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 1.6 2017/01/24 23:29:14 christos Exp $"); 26 #endif 27 28 #ifdef HAVE_CONFIG_H 29 #include "config.h" 30 #endif 31 32 #include <netdissect-stdinc.h> 33 34 #include <stdio.h> 35 #include <string.h> 36 #include <stdlib.h> 37 38 #include "netdissect.h" 39 40 struct z_packet { 41 const char *version; 42 int numfields; 43 int kind; 44 const char *uid; 45 int port; 46 int auth; 47 int authlen; 48 const char *authdata; 49 const char *class; 50 const char *inst; 51 const char *opcode; 52 const char *sender; 53 const char *recipient; 54 const char *format; 55 int cksum; 56 int multi; 57 const char *multi_uid; 58 /* Other fields follow here.. */ 59 }; 60 61 enum z_packet_type { 62 Z_PACKET_UNSAFE = 0, 63 Z_PACKET_UNACKED, 64 Z_PACKET_ACKED, 65 Z_PACKET_HMACK, 66 Z_PACKET_HMCTL, 67 Z_PACKET_SERVACK, 68 Z_PACKET_SERVNAK, 69 Z_PACKET_CLIENTACK, 70 Z_PACKET_STAT 71 }; 72 73 static const struct tok z_types[] = { 74 { Z_PACKET_UNSAFE, "unsafe" }, 75 { Z_PACKET_UNACKED, "unacked" }, 76 { Z_PACKET_ACKED, "acked" }, 77 { Z_PACKET_HMACK, "hm-ack" }, 78 { Z_PACKET_HMCTL, "hm-ctl" }, 79 { Z_PACKET_SERVACK, "serv-ack" }, 80 { Z_PACKET_SERVNAK, "serv-nak" }, 81 { Z_PACKET_CLIENTACK, "client-ack" }, 82 { Z_PACKET_STAT, "stat" } 83 }; 84 85 static char z_buf[256]; 86 87 static const char * 88 parse_field(netdissect_options *ndo, const char **pptr, int *len) 89 { 90 const char *s; 91 92 if (*len <= 0 || !pptr || !*pptr) 93 return NULL; 94 if (*pptr > (const char *) ndo->ndo_snapend) 95 return NULL; 96 97 s = *pptr; 98 while (*pptr <= (const char *) ndo->ndo_snapend && *len >= 0 && **pptr) { 99 (*pptr)++; 100 (*len)--; 101 } 102 (*pptr)++; 103 (*len)--; 104 if (*len < 0 || *pptr > (const char *) ndo->ndo_snapend) 105 return NULL; 106 return s; 107 } 108 109 static const char * 110 z_triple(const char *class, const char *inst, const char *recipient) 111 { 112 if (!*recipient) 113 recipient = "*"; 114 snprintf(z_buf, sizeof(z_buf), "<%s,%s,%s>", class, inst, recipient); 115 z_buf[sizeof(z_buf)-1] = '\0'; 116 return z_buf; 117 } 118 119 static const char * 120 str_to_lower(const char *string) 121 { 122 char *zb_string; 123 124 strncpy(z_buf, string, sizeof(z_buf)); 125 z_buf[sizeof(z_buf)-1] = '\0'; 126 127 zb_string = z_buf; 128 while (*zb_string) { 129 *zb_string = tolower((unsigned char)(*zb_string)); 130 zb_string++; 131 } 132 133 return z_buf; 134 } 135 136 void 137 zephyr_print(netdissect_options *ndo, const u_char *cp, int length) 138 { 139 struct z_packet z; 140 const char *parse = (const char *) cp; 141 int parselen = length; 142 const char *s; 143 int lose = 0; 144 145 /* squelch compiler warnings */ 146 147 z.kind = 0; 148 z.class = 0; 149 z.inst = 0; 150 z.opcode = 0; 151 z.sender = 0; 152 z.recipient = 0; 153 154 memset(&z, 0, sizeof(z)); /* XXX gcc */ 155 156 #define PARSE_STRING \ 157 s = parse_field(ndo, &parse, &parselen); \ 158 if (!s) lose = 1; 159 160 #define PARSE_FIELD_INT(field) \ 161 PARSE_STRING \ 162 if (!lose) field = strtol(s, 0, 16); 163 164 #define PARSE_FIELD_STR(field) \ 165 PARSE_STRING \ 166 if (!lose) field = s; 167 168 PARSE_FIELD_STR(z.version); 169 if (lose) return; 170 if (strncmp(z.version, "ZEPH", 4)) 171 return; 172 173 PARSE_FIELD_INT(z.numfields); 174 PARSE_FIELD_INT(z.kind); 175 PARSE_FIELD_STR(z.uid); 176 PARSE_FIELD_INT(z.port); 177 PARSE_FIELD_INT(z.auth); 178 PARSE_FIELD_INT(z.authlen); 179 PARSE_FIELD_STR(z.authdata); 180 PARSE_FIELD_STR(z.class); 181 PARSE_FIELD_STR(z.inst); 182 PARSE_FIELD_STR(z.opcode); 183 PARSE_FIELD_STR(z.sender); 184 PARSE_FIELD_STR(z.recipient); 185 PARSE_FIELD_STR(z.format); 186 PARSE_FIELD_INT(z.cksum); 187 PARSE_FIELD_INT(z.multi); 188 PARSE_FIELD_STR(z.multi_uid); 189 190 if (lose) { 191 ND_PRINT((ndo, " [|zephyr] (%d)", length)); 192 return; 193 } 194 195 ND_PRINT((ndo, " zephyr")); 196 if (strncmp(z.version+4, "0.2", 3)) { 197 ND_PRINT((ndo, " v%s", z.version+4)); 198 return; 199 } 200 201 ND_PRINT((ndo, " %s", tok2str(z_types, "type %d", z.kind))); 202 if (z.kind == Z_PACKET_SERVACK) { 203 /* Initialization to silence warnings */ 204 const char *ackdata = NULL; 205 PARSE_FIELD_STR(ackdata); 206 if (!lose && strcmp(ackdata, "SENT")) 207 ND_PRINT((ndo, "/%s", str_to_lower(ackdata))); 208 } 209 if (*z.sender) ND_PRINT((ndo, " %s", z.sender)); 210 211 if (!strcmp(z.class, "USER_LOCATE")) { 212 if (!strcmp(z.opcode, "USER_HIDE")) 213 ND_PRINT((ndo, " hide")); 214 else if (!strcmp(z.opcode, "USER_UNHIDE")) 215 ND_PRINT((ndo, " unhide")); 216 else 217 ND_PRINT((ndo, " locate %s", z.inst)); 218 return; 219 } 220 221 if (!strcmp(z.class, "ZEPHYR_ADMIN")) { 222 ND_PRINT((ndo, " zephyr-admin %s", str_to_lower(z.opcode))); 223 return; 224 } 225 226 if (!strcmp(z.class, "ZEPHYR_CTL")) { 227 if (!strcmp(z.inst, "CLIENT")) { 228 if (!strcmp(z.opcode, "SUBSCRIBE") || 229 !strcmp(z.opcode, "SUBSCRIBE_NODEFS") || 230 !strcmp(z.opcode, "UNSUBSCRIBE")) { 231 232 ND_PRINT((ndo, " %ssub%s", strcmp(z.opcode, "SUBSCRIBE") ? "un" : "", 233 strcmp(z.opcode, "SUBSCRIBE_NODEFS") ? "" : 234 "-nodefs")); 235 if (z.kind != Z_PACKET_SERVACK) { 236 /* Initialization to silence warnings */ 237 const char *c = NULL, *i = NULL, *r = NULL; 238 PARSE_FIELD_STR(c); 239 PARSE_FIELD_STR(i); 240 PARSE_FIELD_STR(r); 241 if (!lose) ND_PRINT((ndo, " %s", z_triple(c, i, r))); 242 } 243 return; 244 } 245 246 if (!strcmp(z.opcode, "GIMME")) { 247 ND_PRINT((ndo, " ret")); 248 return; 249 } 250 251 if (!strcmp(z.opcode, "GIMMEDEFS")) { 252 ND_PRINT((ndo, " gimme-defs")); 253 return; 254 } 255 256 if (!strcmp(z.opcode, "CLEARSUB")) { 257 ND_PRINT((ndo, " clear-subs")); 258 return; 259 } 260 261 ND_PRINT((ndo, " %s", str_to_lower(z.opcode))); 262 return; 263 } 264 265 if (!strcmp(z.inst, "HM")) { 266 ND_PRINT((ndo, " %s", str_to_lower(z.opcode))); 267 return; 268 } 269 270 if (!strcmp(z.inst, "REALM")) { 271 if (!strcmp(z.opcode, "ADD_SUBSCRIBE")) 272 ND_PRINT((ndo, " realm add-subs")); 273 if (!strcmp(z.opcode, "REQ_SUBSCRIBE")) 274 ND_PRINT((ndo, " realm req-subs")); 275 if (!strcmp(z.opcode, "RLM_SUBSCRIBE")) 276 ND_PRINT((ndo, " realm rlm-sub")); 277 if (!strcmp(z.opcode, "RLM_UNSUBSCRIBE")) 278 ND_PRINT((ndo, " realm rlm-unsub")); 279 return; 280 } 281 } 282 283 if (!strcmp(z.class, "HM_CTL")) { 284 ND_PRINT((ndo, " hm_ctl %s", str_to_lower(z.inst))); 285 ND_PRINT((ndo, " %s", str_to_lower(z.opcode))); 286 return; 287 } 288 289 if (!strcmp(z.class, "HM_STAT")) { 290 if (!strcmp(z.inst, "HMST_CLIENT") && !strcmp(z.opcode, "GIMMESTATS")) { 291 ND_PRINT((ndo, " get-client-stats")); 292 return; 293 } 294 } 295 296 if (!strcmp(z.class, "WG_CTL")) { 297 ND_PRINT((ndo, " wg_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, "LOGIN")) { 303 if (!strcmp(z.opcode, "USER_FLUSH")) { 304 ND_PRINT((ndo, " flush_locs")); 305 return; 306 } 307 308 if (!strcmp(z.opcode, "NONE") || 309 !strcmp(z.opcode, "OPSTAFF") || 310 !strcmp(z.opcode, "REALM-VISIBLE") || 311 !strcmp(z.opcode, "REALM-ANNOUNCED") || 312 !strcmp(z.opcode, "NET-VISIBLE") || 313 !strcmp(z.opcode, "NET-ANNOUNCED")) { 314 ND_PRINT((ndo, " set-exposure %s", str_to_lower(z.opcode))); 315 return; 316 } 317 } 318 319 if (!*z.recipient) 320 z.recipient = "*"; 321 322 ND_PRINT((ndo, " to %s", z_triple(z.class, z.inst, z.recipient))); 323 if (*z.opcode) 324 ND_PRINT((ndo, " op %s", z.opcode)); 325 } 326