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 };
  81
  82 static char z_buf[256];
  83
  84 static const char *
  85 parse_field(netdissect_options *ndo, const char **pptr, int *len)
  86 {
  87     const char *s;
  88
  89     if (*len <= 0 || !pptr || !*pptr)
  90         return NULL;
  91     if (*pptr > (const char *) ndo->ndo_snapend)
  92         return NULL;
  93
  94     s = *pptr;
  95     while (*pptr <= (const char *) ndo->ndo_snapend && *len >= 0 && **pptr) {
  96         (*pptr)++;
  97         (*len)--;
  98     }
  99     (*pptr)++;
 100     (*len)--;
 101     if (*len < 0 || *pptr > (const char *) ndo->ndo_snapend)
 102         return NULL;
 103     return s;
 104 }
 105
 106 static const char *
 107 z_triple(const char *class, const char *inst, const char *recipient)
 108 {
 109     if (!*recipient)
 110         recipient = "*";
 111     snprintf(z_buf, sizeof(z_buf), "<%s,%s,%s>", class, inst, recipient);
 112     z_buf[sizeof(z_buf)-1] = '\0';
 113     return z_buf;
 114 }
 115
 116 static const char *
 117 str_to_lower(const char *string)
 118 {
 119     char *zb_string;
 120
 121     strncpy(z_buf, string, sizeof(z_buf));
 122     z_buf[sizeof(z_buf)-1] = '\0';
 123
 124     zb_string = z_buf;
 125     while (*zb_string) {
 126         *zb_string = tolower((unsigned char)(*zb_string));
 127         zb_string++;
 128     }
 129
 130     return z_buf;
 131 }
 132
 133 void
 134 zephyr_print(netdissect_options *ndo, const u_char *cp, int length)
 135 {
 136     struct z_packet z;
 137     const char *parse = (const char *) cp;
 138     int parselen = length;
 139     const char *s;
 140     int lose = 0;
 141
 142     /* squelch compiler warnings */
 143
 144     z.kind = 0;
 145     z.class = 0;
 146     z.inst = 0;
 147     z.opcode = 0;
 148     z.sender = 0;
 149     z.recipient = 0;
 150
 151 #define PARSE_STRING                            \
 152         s = parse_field(ndo, &parse, &parselen);        \
 153         if (!s) lose = 1;
 154
 155 #define PARSE_FIELD_INT(field)                  \
 156         PARSE_STRING                            \
 157         if (!lose) field = strtol(s, 0, 16);
 158
 159 #define PARSE_FIELD_STR(field)                  \
 160         PARSE_STRING                            \
 161         if (!lose) field = s;
 162
 163     PARSE_FIELD_STR(z.version);
 164     if (lose) return;
 165     if (strncmp(z.version, "ZEPH", 4))
 166         return;
 167
 168     PARSE_FIELD_INT(z.numfields);
 169     PARSE_FIELD_INT(z.kind);
 170     PARSE_FIELD_STR(z.uid);
 171     PARSE_FIELD_INT(z.port);
 172     PARSE_FIELD_INT(z.auth);
 173     PARSE_FIELD_INT(z.authlen);
 174     PARSE_FIELD_STR(z.authdata);
 175     PARSE_FIELD_STR(z.class);
 176     PARSE_FIELD_STR(z.inst);
 177     PARSE_FIELD_STR(z.opcode);
 178     PARSE_FIELD_STR(z.sender);
 179     PARSE_FIELD_STR(z.recipient);
 180     PARSE_FIELD_STR(z.format);
 181     PARSE_FIELD_INT(z.cksum);
 182     PARSE_FIELD_INT(z.multi);
 183     PARSE_FIELD_STR(z.multi_uid);
 184
 185     if (lose) {
 186         ND_PRINT((ndo, " [|zephyr] (%d)", length));
 187         return;
 188     }
 189
 190     ND_PRINT((ndo, " zephyr"));
 191     if (strncmp(z.version+4, "0.2", 3)) {
 192         ND_PRINT((ndo, " v%s", z.version+4));
 193         return;
 194     }
 195
 196     ND_PRINT((ndo, " %s", tok2str(z_types, "type %d", z.kind)));
 197     if (z.kind == Z_PACKET_SERVACK) {
 198         /* Initialization to silence warnings */
 199         const char *ackdata = NULL;
 200         PARSE_FIELD_STR(ackdata);
 201         if (!lose && strcmp(ackdata, "SENT"))
 202             ND_PRINT((ndo, "/%s", str_to_lower(ackdata)));
 203     }
 204     if (*z.sender) ND_PRINT((ndo, " %s", z.sender));
 205
 206     if (!strcmp(z.class, "USER_LOCATE")) {
 207         if (!strcmp(z.opcode, "USER_HIDE"))
 208             ND_PRINT((ndo, " hide"));
 209         else if (!strcmp(z.opcode, "USER_UNHIDE"))
 210             ND_PRINT((ndo, " unhide"));
 211         else
 212             ND_PRINT((ndo, " locate %s", z.inst));
 213         return;
 214     }
 215
 216     if (!strcmp(z.class, "ZEPHYR_ADMIN")) {
 217         ND_PRINT((ndo, " zephyr-admin %s", str_to_lower(z.opcode)));
 218         return;
 219     }
 220
 221     if (!strcmp(z.class, "ZEPHYR_CTL")) {
 222         if (!strcmp(z.inst, "CLIENT")) {
 223             if (!strcmp(z.opcode, "SUBSCRIBE") ||
 224                 !strcmp(z.opcode, "SUBSCRIBE_NODEFS") ||
 225                 !strcmp(z.opcode, "UNSUBSCRIBE")) {
 226
 227                 ND_PRINT((ndo, " %ssub%s", strcmp(z.opcode, "SUBSCRIBE") ? "un" : "",
 228                                    strcmp(z.opcode, "SUBSCRIBE_NODEFS") ? "" :
 229                                                                    "-nodefs"));
 230                 if (z.kind != Z_PACKET_SERVACK) {
 231                     /* Initialization to silence warnings */
 232                     const char *c = NULL, *i = NULL, *r = NULL;
 233                     PARSE_FIELD_STR(c);
 234                     PARSE_FIELD_STR(i);
 235                     PARSE_FIELD_STR(r);
 236                     if (!lose) ND_PRINT((ndo, " %s", z_triple(c, i, r)));
 237                 }
 238                 return;
 239             }
 240
 241             if (!strcmp(z.opcode, "GIMME")) {
 242                 ND_PRINT((ndo, " ret"));
 243                 return;
 244             }
 245
 246             if (!strcmp(z.opcode, "GIMMEDEFS")) {
 247                 ND_PRINT((ndo, " gimme-defs"));
 248                 return;
 249             }
 250
 251             if (!strcmp(z.opcode, "CLEARSUB")) {
 252                 ND_PRINT((ndo, " clear-subs"));
 253                 return;
 254             }
 255
 256             ND_PRINT((ndo, " %s", str_to_lower(z.opcode)));
 257             return;
 258         }
 259
 260         if (!strcmp(z.inst, "HM")) {
 261             ND_PRINT((ndo, " %s", str_to_lower(z.opcode)));
 262             return;
 263         }
 264
 265         if (!strcmp(z.inst, "REALM")) {
 266             if (!strcmp(z.opcode, "ADD_SUBSCRIBE"))
 267                 ND_PRINT((ndo, " realm add-subs"));
 268             if (!strcmp(z.opcode, "REQ_SUBSCRIBE"))
 269                 ND_PRINT((ndo, " realm req-subs"));
 270             if (!strcmp(z.opcode, "RLM_SUBSCRIBE"))
 271                 ND_PRINT((ndo, " realm rlm-sub"));
 272             if (!strcmp(z.opcode, "RLM_UNSUBSCRIBE"))
 273                 ND_PRINT((ndo, " realm rlm-unsub"));
 274             return;
 275         }
 276     }
 277
 278     if (!strcmp(z.class, "HM_CTL")) {
 279         ND_PRINT((ndo, " hm_ctl %s", str_to_lower(z.inst)));
 280         ND_PRINT((ndo, " %s", str_to_lower(z.opcode)));
 281         return;
 282     }
 283
 284     if (!strcmp(z.class, "HM_STAT")) {
 285         if (!strcmp(z.inst, "HMST_CLIENT") && !strcmp(z.opcode, "GIMMESTATS")) {
 286             ND_PRINT((ndo, " get-client-stats"));
 287             return;
 288         }
 289     }
 290
 291     if (!strcmp(z.class, "WG_CTL")) {
 292         ND_PRINT((ndo, " wg_ctl %s", str_to_lower(z.inst)));
 293         ND_PRINT((ndo, " %s", str_to_lower(z.opcode)));
 294         return;
 295     }
 296
 297     if (!strcmp(z.class, "LOGIN")) {
 298         if (!strcmp(z.opcode, "USER_FLUSH")) {
 299             ND_PRINT((ndo, " flush_locs"));
 300             return;
 301         }
 302
 303         if (!strcmp(z.opcode, "NONE") ||
 304             !strcmp(z.opcode, "OPSTAFF") ||
 305             !strcmp(z.opcode, "REALM-VISIBLE") ||
 306             !strcmp(z.opcode, "REALM-ANNOUNCED") ||
 307             !strcmp(z.opcode, "NET-VISIBLE") ||
 308             !strcmp(z.opcode, "NET-ANNOUNCED")) {
 309             ND_PRINT((ndo, " set-exposure %s", str_to_lower(z.opcode)));
 310             return;
 311         }
 312     }
 313
 314     if (!*z.recipient)
 315         z.recipient = "*";
 316
 317     ND_PRINT((ndo, " to %s", z_triple(z.class, z.inst, z.recipient)));
 318     if (*z.opcode)
 319         ND_PRINT((ndo, " op %s", z.opcode));
 320 }