The Tcpdump Group git mirrors - tcpdump/blob - print-zephyr.c

   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 }