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 #ifdef HAVE_CONFIG_H
  24 #include "config.h"
  25 #endif
  26
  27 #include <netdissect-stdinc.h>
  28
  29 #include <stdio.h>
  30 #include <string.h>
  31 #include <stdlib.h>
  32
  33 #include "netdissect.h"
  34
  35 struct z_packet {
  36     const char *version;
  37     int numfields;
  38     int kind;
  39     const char *uid;
  40     int port;
  41     int auth;
  42     int authlen;
  43     const char *authdata;
  44     const char *class;
  45     const char *inst;
  46     const char *opcode;
  47     const char *sender;
  48     const char *recipient;
  49     const char *format;
  50     int cksum;
  51     int multi;
  52     const char *multi_uid;
  53     /* Other fields follow here.. */
  54 };
  55
  56 enum z_packet_type {
  57     Z_PACKET_UNSAFE = 0,
  58     Z_PACKET_UNACKED,
  59     Z_PACKET_ACKED,
  60     Z_PACKET_HMACK,
  61     Z_PACKET_HMCTL,
  62     Z_PACKET_SERVACK,
  63     Z_PACKET_SERVNAK,
  64     Z_PACKET_CLIENTACK,
  65     Z_PACKET_STAT
  66 };
  67
  68 static const struct tok z_types[] = {
  69     { Z_PACKET_UNSAFE,          "unsafe" },
  70     { Z_PACKET_UNACKED,         "unacked" },
  71     { Z_PACKET_ACKED,           "acked" },
  72     { Z_PACKET_HMACK,           "hm-ack" },
  73     { Z_PACKET_HMCTL,           "hm-ctl" },
  74     { Z_PACKET_SERVACK,         "serv-ack" },
  75     { Z_PACKET_SERVNAK,         "serv-nak" },
  76     { Z_PACKET_CLIENTACK,       "client-ack" },
  77     { Z_PACKET_STAT,            "stat" }
  78 };
  79
  80 static char z_buf[256];
  81
  82 static const char *
  83 parse_field(netdissect_options *ndo, const char **pptr, int *len)
  84 {
  85     const char *s;
  86
  87     if (*len <= 0 || !pptr || !*pptr)
  88         return NULL;
  89     if (*pptr > (const char *) ndo->ndo_snapend)
  90         return NULL;
  91
  92     s = *pptr;
  93     while (*pptr <= (const char *) ndo->ndo_snapend && *len >= 0 && **pptr) {
  94         (*pptr)++;
  95         (*len)--;
  96     }
  97     (*pptr)++;
  98     (*len)--;
  99     if (*len < 0 || *pptr > (const char *) ndo->ndo_snapend)
 100         return NULL;
 101     return s;
 102 }
 103
 104 static const char *
 105 z_triple(const char *class, const char *inst, const char *recipient)
 106 {
 107     if (!*recipient)
 108         recipient = "*";
 109     snprintf(z_buf, sizeof(z_buf), "<%s,%s,%s>", class, inst, recipient);
 110     z_buf[sizeof(z_buf)-1] = '\0';
 111     return z_buf;
 112 }
 113
 114 static const char *
 115 str_to_lower(const char *string)
 116 {
 117     char *zb_string;
 118
 119     strncpy(z_buf, string, sizeof(z_buf));
 120     z_buf[sizeof(z_buf)-1] = '\0';
 121
 122     zb_string = z_buf;
 123     while (*zb_string) {
 124         *zb_string = tolower((unsigned char)(*zb_string));
 125         zb_string++;
 126     }
 127
 128     return z_buf;
 129 }
 130
 131 void
 132 zephyr_print(netdissect_options *ndo, const u_char *cp, int length)
 133 {
 134     struct z_packet z;
 135     const char *parse = (const char *) cp;
 136     int parselen = length;
 137     const char *s;
 138     int lose = 0;
 139
 140     /* squelch compiler warnings */
 141
 142     z.kind = 0;
 143     z.class = 0;
 144     z.inst = 0;
 145     z.opcode = 0;
 146     z.sender = 0;
 147     z.recipient = 0;
 148
 149 #define PARSE_STRING                            \
 150         s = parse_field(ndo, &parse, &parselen);        \
 151         if (!s) lose = 1;
 152
 153 #define PARSE_FIELD_INT(field)                  \
 154         PARSE_STRING                            \
 155         if (!lose) field = strtol(s, 0, 16);
 156
 157 #define PARSE_FIELD_STR(field)                  \
 158         PARSE_STRING                            \
 159         if (!lose) field = s;
 160
 161     PARSE_FIELD_STR(z.version);
 162     if (lose) return;
 163     if (strncmp(z.version, "ZEPH", 4))
 164         return;
 165
 166     PARSE_FIELD_INT(z.numfields);
 167     PARSE_FIELD_INT(z.kind);
 168     PARSE_FIELD_STR(z.uid);
 169     PARSE_FIELD_INT(z.port);
 170     PARSE_FIELD_INT(z.auth);
 171     PARSE_FIELD_INT(z.authlen);
 172     PARSE_FIELD_STR(z.authdata);
 173     PARSE_FIELD_STR(z.class);
 174     PARSE_FIELD_STR(z.inst);
 175     PARSE_FIELD_STR(z.opcode);
 176     PARSE_FIELD_STR(z.sender);
 177     PARSE_FIELD_STR(z.recipient);
 178     PARSE_FIELD_STR(z.format);
 179     PARSE_FIELD_INT(z.cksum);
 180     PARSE_FIELD_INT(z.multi);
 181     PARSE_FIELD_STR(z.multi_uid);
 182
 183     if (lose) {
 184         ND_PRINT((ndo, " [|zephyr] (%d)", length));
 185         return;
 186     }
 187
 188     ND_PRINT((ndo, " zephyr"));
 189     if (strncmp(z.version+4, "0.2", 3)) {
 190         ND_PRINT((ndo, " v%s", z.version+4));
 191         return;
 192     }
 193
 194     ND_PRINT((ndo, " %s", tok2str(z_types, "type %d", z.kind)));
 195     if (z.kind == Z_PACKET_SERVACK) {
 196         /* Initialization to silence warnings */
 197         const char *ackdata = NULL;
 198         PARSE_FIELD_STR(ackdata);
 199         if (!lose && strcmp(ackdata, "SENT"))
 200             ND_PRINT((ndo, "/%s", str_to_lower(ackdata)));
 201     }
 202     if (*z.sender) ND_PRINT((ndo, " %s", z.sender));
 203
 204     if (!strcmp(z.class, "USER_LOCATE")) {
 205         if (!strcmp(z.opcode, "USER_HIDE"))
 206             ND_PRINT((ndo, " hide"));
 207         else if (!strcmp(z.opcode, "USER_UNHIDE"))
 208             ND_PRINT((ndo, " unhide"));
 209         else
 210             ND_PRINT((ndo, " locate %s", z.inst));
 211         return;
 212     }
 213
 214     if (!strcmp(z.class, "ZEPHYR_ADMIN")) {
 215         ND_PRINT((ndo, " zephyr-admin %s", str_to_lower(z.opcode)));
 216         return;
 217     }
 218
 219     if (!strcmp(z.class, "ZEPHYR_CTL")) {
 220         if (!strcmp(z.inst, "CLIENT")) {
 221             if (!strcmp(z.opcode, "SUBSCRIBE") ||
 222                 !strcmp(z.opcode, "SUBSCRIBE_NODEFS") ||
 223                 !strcmp(z.opcode, "UNSUBSCRIBE")) {
 224
 225                 ND_PRINT((ndo, " %ssub%s", strcmp(z.opcode, "SUBSCRIBE") ? "un" : "",
 226                                    strcmp(z.opcode, "SUBSCRIBE_NODEFS") ? "" :
 227                                                                    "-nodefs"));
 228                 if (z.kind != Z_PACKET_SERVACK) {
 229                     /* Initialization to silence warnings */
 230                     const char *c = NULL, *i = NULL, *r = NULL;
 231                     PARSE_FIELD_STR(c);
 232                     PARSE_FIELD_STR(i);
 233                     PARSE_FIELD_STR(r);
 234                     if (!lose) ND_PRINT((ndo, " %s", z_triple(c, i, r)));
 235                 }
 236                 return;
 237             }
 238
 239             if (!strcmp(z.opcode, "GIMME")) {
 240                 ND_PRINT((ndo, " ret"));
 241                 return;
 242             }
 243
 244             if (!strcmp(z.opcode, "GIMMEDEFS")) {
 245                 ND_PRINT((ndo, " gimme-defs"));
 246                 return;
 247             }
 248
 249             if (!strcmp(z.opcode, "CLEARSUB")) {
 250                 ND_PRINT((ndo, " clear-subs"));
 251                 return;
 252             }
 253
 254             ND_PRINT((ndo, " %s", str_to_lower(z.opcode)));
 255             return;
 256         }
 257
 258         if (!strcmp(z.inst, "HM")) {
 259             ND_PRINT((ndo, " %s", str_to_lower(z.opcode)));
 260             return;
 261         }
 262
 263         if (!strcmp(z.inst, "REALM")) {
 264             if (!strcmp(z.opcode, "ADD_SUBSCRIBE"))
 265                 ND_PRINT((ndo, " realm add-subs"));
 266             if (!strcmp(z.opcode, "REQ_SUBSCRIBE"))
 267                 ND_PRINT((ndo, " realm req-subs"));
 268             if (!strcmp(z.opcode, "RLM_SUBSCRIBE"))
 269                 ND_PRINT((ndo, " realm rlm-sub"));
 270             if (!strcmp(z.opcode, "RLM_UNSUBSCRIBE"))
 271                 ND_PRINT((ndo, " realm rlm-unsub"));
 272             return;
 273         }
 274     }
 275
 276     if (!strcmp(z.class, "HM_CTL")) {
 277         ND_PRINT((ndo, " hm_ctl %s", str_to_lower(z.inst)));
 278         ND_PRINT((ndo, " %s", str_to_lower(z.opcode)));
 279         return;
 280     }
 281
 282     if (!strcmp(z.class, "HM_STAT")) {
 283         if (!strcmp(z.inst, "HMST_CLIENT") && !strcmp(z.opcode, "GIMMESTATS")) {
 284             ND_PRINT((ndo, " get-client-stats"));
 285             return;
 286         }
 287     }
 288
 289     if (!strcmp(z.class, "WG_CTL")) {
 290         ND_PRINT((ndo, " wg_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, "LOGIN")) {
 296         if (!strcmp(z.opcode, "USER_FLUSH")) {
 297             ND_PRINT((ndo, " flush_locs"));
 298             return;
 299         }
 300
 301         if (!strcmp(z.opcode, "NONE") ||
 302             !strcmp(z.opcode, "OPSTAFF") ||
 303             !strcmp(z.opcode, "REALM-VISIBLE") ||
 304             !strcmp(z.opcode, "REALM-ANNOUNCED") ||
 305             !strcmp(z.opcode, "NET-VISIBLE") ||
 306             !strcmp(z.opcode, "NET-ANNOUNCED")) {
 307             ND_PRINT((ndo, " set-exposure %s", str_to_lower(z.opcode)));
 308             return;
 309         }
 310     }
 311
 312     if (!*z.recipient)
 313         z.recipient = "*";
 314
 315     ND_PRINT((ndo, " to %s", z_triple(z.class, z.inst, z.recipient)));
 316     if (*z.opcode)
 317         ND_PRINT((ndo, " op %s", z.opcode));
 318 }