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

   1 /*
   2  * Decode and print Zephyr packets.
   3  *
   4  *      https://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-ctype.h"
  36
  37 #include "netdissect.h"
  38 #include "extract.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     { 0,                        NULL }
  84 };
  85
  86 static char z_buf[256];
  87
  88 static const char *
  89 parse_field(netdissect_options *ndo, const char **pptr, int *len)
  90 {
  91     const char *s;
  92
  93     /* Start of string */
  94     s = *pptr;
  95     /* Scan for the NUL terminator */
  96     for (;;) {
  97         if (*len == 0) {
  98             /* Ran out of packet data without finding it */
  99             return NULL;
 100         }
 101         if (GET_U_1(*pptr) == '\0') {
 102             /* Found it */
 103             break;
 104         }
 105         /* Keep scanning */
 106         (*pptr)++;
 107         (*len)--;
 108     }
 109     /* Skip the NUL terminator */
 110     (*pptr)++;
 111     (*len)--;
 112     return s;
 113 }
 114
 115 static const char *
 116 z_triple(const char *class, const char *inst, const char *recipient)
 117 {
 118     if (!*recipient)
 119         recipient = "*";
 120     snprintf(z_buf, sizeof(z_buf), "<%s,%s,%s>", class, inst, recipient);
 121     z_buf[sizeof(z_buf)-1] = '\0';
 122     return z_buf;
 123 }
 124
 125 static const char *
 126 str_to_lower(const char *string)
 127 {
 128     char *zb_string;
 129
 130     strncpy(z_buf, string, sizeof(z_buf));
 131     z_buf[sizeof(z_buf)-1] = '\0';
 132
 133     zb_string = z_buf;
 134     while (*zb_string) {
 135         *zb_string = ND_ASCII_TOLOWER(*zb_string);
 136         zb_string++;
 137     }
 138
 139     return z_buf;
 140 }
 141
 142 void
 143 zephyr_print(netdissect_options *ndo, const u_char *cp, u_int length)
 144 {
 145     struct z_packet z = {
 146         NULL,   /* version */
 147         0,      /* numfields */
 148         0,      /* kind */
 149         NULL,   /* uid */
 150         0,      /* port */
 151         0,      /* auth */
 152         0,      /* authlen */
 153         NULL,   /* authdata */
 154         NULL,   /* class */
 155         NULL,   /* inst */
 156         NULL,   /* opcode */
 157         NULL,   /* sender */
 158         NULL,   /* recipient */
 159         NULL,   /* format */
 160         0,      /* cksum */
 161         0,      /* multi */
 162         NULL    /* multi_uid */
 163     };
 164     const char *parse = (const char *) cp;
 165     int parselen = length;
 166     const char *s;
 167     int lose = 0;
 168
 169     ndo->ndo_protocol = "zephyr";
 170     /* squelch compiler warnings */
 171
 172 #define PARSE_STRING                                            \
 173         s = parse_field(ndo, &parse, &parselen);        \
 174         if (!s) lose = 1;
 175
 176 #define PARSE_FIELD_INT(field)                  \
 177         PARSE_STRING                            \
 178         if (!lose) field = strtol(s, 0, 16);
 179
 180 #define PARSE_FIELD_STR(field)                  \
 181         PARSE_STRING                            \
 182         if (!lose) field = s;
 183
 184     PARSE_FIELD_STR(z.version);
 185     if (lose)
 186         goto invalid;
 187
 188     if (strncmp(z.version, "ZEPH", 4))
 189         return;
 190
 191     PARSE_FIELD_INT(z.numfields);
 192     PARSE_FIELD_INT(z.kind);
 193     PARSE_FIELD_STR(z.uid);
 194     PARSE_FIELD_INT(z.port);
 195     PARSE_FIELD_INT(z.auth);
 196     PARSE_FIELD_INT(z.authlen);
 197     PARSE_FIELD_STR(z.authdata);
 198     PARSE_FIELD_STR(z.class);
 199     PARSE_FIELD_STR(z.inst);
 200     PARSE_FIELD_STR(z.opcode);
 201     PARSE_FIELD_STR(z.sender);
 202     PARSE_FIELD_STR(z.recipient);
 203     PARSE_FIELD_STR(z.format);
 204     PARSE_FIELD_INT(z.cksum);
 205     PARSE_FIELD_INT(z.multi);
 206     PARSE_FIELD_STR(z.multi_uid);
 207
 208     if (lose)
 209         goto invalid;
 210
 211     ND_PRINT(" zephyr");
 212     if (strncmp(z.version+4, "0.2", 3)) {
 213         ND_PRINT(" v%s", z.version+4);
 214         return;
 215     }
 216
 217     ND_PRINT(" %s", tok2str(z_types, "type %d", z.kind));
 218     if (z.kind == Z_PACKET_SERVACK) {
 219         /* Initialization to silence warnings */
 220         const char *ackdata = NULL;
 221         PARSE_FIELD_STR(ackdata);
 222         if (!lose && strcmp(ackdata, "SENT"))
 223             ND_PRINT("/%s", str_to_lower(ackdata));
 224     }
 225     if (*z.sender) ND_PRINT(" %s", z.sender);
 226
 227     if (!strcmp(z.class, "USER_LOCATE")) {
 228         if (!strcmp(z.opcode, "USER_HIDE"))
 229             ND_PRINT(" hide");
 230         else if (!strcmp(z.opcode, "USER_UNHIDE"))
 231             ND_PRINT(" unhide");
 232         else
 233             ND_PRINT(" locate %s", z.inst);
 234         return;
 235     }
 236
 237     if (!strcmp(z.class, "ZEPHYR_ADMIN")) {
 238         ND_PRINT(" zephyr-admin %s", str_to_lower(z.opcode));
 239         return;
 240     }
 241
 242     if (!strcmp(z.class, "ZEPHYR_CTL")) {
 243         if (!strcmp(z.inst, "CLIENT")) {
 244             if (!strcmp(z.opcode, "SUBSCRIBE") ||
 245                 !strcmp(z.opcode, "SUBSCRIBE_NODEFS") ||
 246                 !strcmp(z.opcode, "UNSUBSCRIBE")) {
 247
 248                 ND_PRINT(" %ssub%s", strcmp(z.opcode, "SUBSCRIBE") ? "un" : "",
 249                                    strcmp(z.opcode, "SUBSCRIBE_NODEFS") ? "" :
 250                                                                    "-nodefs");
 251                 if (z.kind != Z_PACKET_SERVACK) {
 252                     /* Initialization to silence warnings */
 253                     const char *c = NULL, *i = NULL, *r = NULL;
 254                     PARSE_FIELD_STR(c);
 255                     PARSE_FIELD_STR(i);
 256                     PARSE_FIELD_STR(r);
 257                     if (!lose) ND_PRINT(" %s", z_triple(c, i, r));
 258                 }
 259                 return;
 260             }
 261
 262             if (!strcmp(z.opcode, "GIMME")) {
 263                 ND_PRINT(" ret");
 264                 return;
 265             }
 266
 267             if (!strcmp(z.opcode, "GIMMEDEFS")) {
 268                 ND_PRINT(" gimme-defs");
 269                 return;
 270             }
 271
 272             if (!strcmp(z.opcode, "CLEARSUB")) {
 273                 ND_PRINT(" clear-subs");
 274                 return;
 275             }
 276
 277             ND_PRINT(" %s", str_to_lower(z.opcode));
 278             return;
 279         }
 280
 281         if (!strcmp(z.inst, "HM")) {
 282             ND_PRINT(" %s", str_to_lower(z.opcode));
 283             return;
 284         }
 285
 286         if (!strcmp(z.inst, "REALM")) {
 287             if (!strcmp(z.opcode, "ADD_SUBSCRIBE"))
 288                 ND_PRINT(" realm add-subs");
 289             if (!strcmp(z.opcode, "REQ_SUBSCRIBE"))
 290                 ND_PRINT(" realm req-subs");
 291             if (!strcmp(z.opcode, "RLM_SUBSCRIBE"))
 292                 ND_PRINT(" realm rlm-sub");
 293             if (!strcmp(z.opcode, "RLM_UNSUBSCRIBE"))
 294                 ND_PRINT(" realm rlm-unsub");
 295             return;
 296         }
 297     }
 298
 299     if (!strcmp(z.class, "HM_CTL")) {
 300         ND_PRINT(" hm_ctl %s", str_to_lower(z.inst));
 301         ND_PRINT(" %s", str_to_lower(z.opcode));
 302         return;
 303     }
 304
 305     if (!strcmp(z.class, "HM_STAT")) {
 306         if (!strcmp(z.inst, "HMST_CLIENT") && !strcmp(z.opcode, "GIMMESTATS")) {
 307             ND_PRINT(" get-client-stats");
 308             return;
 309         }
 310     }
 311
 312     if (!strcmp(z.class, "WG_CTL")) {
 313         ND_PRINT(" wg_ctl %s", str_to_lower(z.inst));
 314         ND_PRINT(" %s", str_to_lower(z.opcode));
 315         return;
 316     }
 317
 318     if (!strcmp(z.class, "LOGIN")) {
 319         if (!strcmp(z.opcode, "USER_FLUSH")) {
 320             ND_PRINT(" flush_locs");
 321             return;
 322         }
 323
 324         if (!strcmp(z.opcode, "NONE") ||
 325             !strcmp(z.opcode, "OPSTAFF") ||
 326             !strcmp(z.opcode, "REALM-VISIBLE") ||
 327             !strcmp(z.opcode, "REALM-ANNOUNCED") ||
 328             !strcmp(z.opcode, "NET-VISIBLE") ||
 329             !strcmp(z.opcode, "NET-ANNOUNCED")) {
 330             ND_PRINT(" set-exposure %s", str_to_lower(z.opcode));
 331             return;
 332         }
 333     }
 334
 335     if (!*z.recipient)
 336         z.recipient = "*";
 337
 338     ND_PRINT(" to %s", z_triple(z.class, z.inst, z.recipient));
 339     if (*z.opcode)
 340         ND_PRINT(" op %s", z.opcode);
 341     return;
 342
 343 invalid:
 344     nd_print_invalid(ndo);
 345 }