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 #define ZEPHYR_PRINT(str1,str2) \
 143 { ND_PRINT("%s", (str1)); fn_print_str(ndo, (const u_char *)(str2)); }
 144
 145 void
 146 zephyr_print(netdissect_options *ndo, const u_char *cp, u_int length)
 147 {
 148     struct z_packet z = {
 149         NULL,   /* version */
 150         0,      /* numfields */
 151         0,      /* kind */
 152         NULL,   /* uid */
 153         0,      /* port */
 154         0,      /* auth */
 155         0,      /* authlen */
 156         NULL,   /* authdata */
 157         NULL,   /* class */
 158         NULL,   /* inst */
 159         NULL,   /* opcode */
 160         NULL,   /* sender */
 161         NULL,   /* recipient */
 162         NULL,   /* format */
 163         0,      /* cksum */
 164         0,      /* multi */
 165         NULL    /* multi_uid */
 166     };
 167     const char *parse = (const char *) cp;
 168     int parselen = length;
 169     const char *s;
 170     int lose = 0;
 171
 172     ndo->ndo_protocol = "zephyr";
 173     /* squelch compiler warnings */
 174
 175 #define PARSE_STRING                                            \
 176         s = parse_field(ndo, &parse, &parselen);        \
 177         if (!s) lose = 1;
 178
 179 #define PARSE_FIELD_INT(field)                  \
 180         PARSE_STRING                            \
 181         if (!lose) field = strtol(s, 0, 16);
 182
 183 #define PARSE_FIELD_STR(field)                  \
 184         PARSE_STRING                            \
 185         if (!lose) field = s;
 186
 187     PARSE_FIELD_STR(z.version);
 188     if (lose)
 189         goto invalid;
 190
 191     if (strncmp(z.version, "ZEPH", 4))
 192         return;
 193
 194     PARSE_FIELD_INT(z.numfields);
 195     PARSE_FIELD_INT(z.kind);
 196     PARSE_FIELD_STR(z.uid);
 197     PARSE_FIELD_INT(z.port);
 198     PARSE_FIELD_INT(z.auth);
 199     PARSE_FIELD_INT(z.authlen);
 200     PARSE_FIELD_STR(z.authdata);
 201     PARSE_FIELD_STR(z.class);
 202     PARSE_FIELD_STR(z.inst);
 203     PARSE_FIELD_STR(z.opcode);
 204     PARSE_FIELD_STR(z.sender);
 205     PARSE_FIELD_STR(z.recipient);
 206     PARSE_FIELD_STR(z.format);
 207     PARSE_FIELD_INT(z.cksum);
 208     PARSE_FIELD_INT(z.multi);
 209     PARSE_FIELD_STR(z.multi_uid);
 210
 211     if (lose)
 212         goto invalid;
 213
 214     ND_PRINT(" zephyr");
 215     if (strncmp(z.version+4, "0.2", 3)) {
 216         ZEPHYR_PRINT(" v", z.version+4)
 217         return;
 218     }
 219
 220     ND_PRINT(" %s", tok2str(z_types, "type %d", z.kind));
 221     if (z.kind == Z_PACKET_SERVACK) {
 222         /* Initialization to silence warnings */
 223         const char *ackdata = NULL;
 224         PARSE_FIELD_STR(ackdata);
 225         if (!lose && strcmp(ackdata, "SENT"))
 226             ZEPHYR_PRINT("/", str_to_lower(ackdata))
 227     }
 228     if (*z.sender) ZEPHYR_PRINT(" ", z.sender);
 229
 230     if (!strcmp(z.class, "USER_LOCATE")) {
 231         if (!strcmp(z.opcode, "USER_HIDE"))
 232             ND_PRINT(" hide");
 233         else if (!strcmp(z.opcode, "USER_UNHIDE"))
 234             ND_PRINT(" unhide");
 235         else
 236             ZEPHYR_PRINT(" locate ", z.inst);
 237         return;
 238     }
 239
 240     if (!strcmp(z.class, "ZEPHYR_ADMIN")) {
 241         ZEPHYR_PRINT(" zephyr-admin ", str_to_lower(z.opcode));
 242         return;
 243     }
 244
 245     if (!strcmp(z.class, "ZEPHYR_CTL")) {
 246         if (!strcmp(z.inst, "CLIENT")) {
 247             if (!strcmp(z.opcode, "SUBSCRIBE") ||
 248                 !strcmp(z.opcode, "SUBSCRIBE_NODEFS") ||
 249                 !strcmp(z.opcode, "UNSUBSCRIBE")) {
 250
 251                 ND_PRINT(" %ssub%s", strcmp(z.opcode, "SUBSCRIBE") ? "un" : "",
 252                                    strcmp(z.opcode, "SUBSCRIBE_NODEFS") ? "" :
 253                                                                    "-nodefs");
 254                 if (z.kind != Z_PACKET_SERVACK) {
 255                     /* Initialization to silence warnings */
 256                     const char *c = NULL, *i = NULL, *r = NULL;
 257                     PARSE_FIELD_STR(c);
 258                     PARSE_FIELD_STR(i);
 259                     PARSE_FIELD_STR(r);
 260                     if (!lose) ZEPHYR_PRINT(" ", z_triple(c, i, r));
 261                 }
 262                 return;
 263             }
 264
 265             if (!strcmp(z.opcode, "GIMME")) {
 266                 ND_PRINT(" ret");
 267                 return;
 268             }
 269
 270             if (!strcmp(z.opcode, "GIMMEDEFS")) {
 271                 ND_PRINT(" gimme-defs");
 272                 return;
 273             }
 274
 275             if (!strcmp(z.opcode, "CLEARSUB")) {
 276                 ND_PRINT(" clear-subs");
 277                 return;
 278             }
 279
 280             ZEPHYR_PRINT(" ", str_to_lower(z.opcode));
 281             return;
 282         }
 283
 284         if (!strcmp(z.inst, "HM")) {
 285             ZEPHYR_PRINT(" ", str_to_lower(z.opcode));
 286             return;
 287         }
 288
 289         if (!strcmp(z.inst, "REALM")) {
 290             if (!strcmp(z.opcode, "ADD_SUBSCRIBE"))
 291                 ND_PRINT(" realm add-subs");
 292             if (!strcmp(z.opcode, "REQ_SUBSCRIBE"))
 293                 ND_PRINT(" realm req-subs");
 294             if (!strcmp(z.opcode, "RLM_SUBSCRIBE"))
 295                 ND_PRINT(" realm rlm-sub");
 296             if (!strcmp(z.opcode, "RLM_UNSUBSCRIBE"))
 297                 ND_PRINT(" realm rlm-unsub");
 298             return;
 299         }
 300     }
 301
 302     if (!strcmp(z.class, "HM_CTL")) {
 303         ZEPHYR_PRINT(" hm_ctl ", str_to_lower(z.inst));
 304         ZEPHYR_PRINT(" ", str_to_lower(z.opcode));
 305         return;
 306     }
 307
 308     if (!strcmp(z.class, "HM_STAT")) {
 309         if (!strcmp(z.inst, "HMST_CLIENT") && !strcmp(z.opcode, "GIMMESTATS")) {
 310             ND_PRINT(" get-client-stats");
 311             return;
 312         }
 313     }
 314
 315     if (!strcmp(z.class, "WG_CTL")) {
 316         ZEPHYR_PRINT(" wg_ctl ", str_to_lower(z.inst));
 317         ZEPHYR_PRINT(" ", str_to_lower(z.opcode));
 318         return;
 319     }
 320
 321     if (!strcmp(z.class, "LOGIN")) {
 322         if (!strcmp(z.opcode, "USER_FLUSH")) {
 323             ND_PRINT(" flush_locs");
 324             return;
 325         }
 326
 327         if (!strcmp(z.opcode, "NONE") ||
 328             !strcmp(z.opcode, "OPSTAFF") ||
 329             !strcmp(z.opcode, "REALM-VISIBLE") ||
 330             !strcmp(z.opcode, "REALM-ANNOUNCED") ||
 331             !strcmp(z.opcode, "NET-VISIBLE") ||
 332             !strcmp(z.opcode, "NET-ANNOUNCED")) {
 333             ZEPHYR_PRINT(" set-exposure ", str_to_lower(z.opcode));
 334             return;
 335         }
 336     }
 337
 338     if (!*z.recipient)
 339         z.recipient = "*";
 340
 341     ZEPHYR_PRINT(" to ", z_triple(z.class, z.inst, z.recipient));
 342     if (*z.opcode)
 343         ZEPHYR_PRINT(" op ", z.opcode);
 344     return;
 345
 346 invalid:
 347     nd_print_invalid(ndo);
 348 }