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

   1 /*
   2  * Copyright (c) 1995, 1996, 1997
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that: (1) source code distributions
   7  * retain the above copyright notice and this paragraph in its entirety, (2)
   8  * distributions including binary code include the above copyright notice and
   9  * this paragraph in its entirety in the documentation or other materials
  10  * provided with the distribution, and (3) all advertising materials mentioning
  11  * features or use of this software display the following acknowledgement:
  12  * ``This product includes software developed by the University of California,
  13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  14  * the University nor the names of its contributors may be used to endorse
  15  * or promote products derived from this software without specific prior
  16  * written permission.
  17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  20  *
  21  * Initial contribution from John Hawkinson (jhawk@mit.edu).
  22  */
  23
  24 #define NETDISSECT_REWORKED
  25 #ifdef HAVE_CONFIG_H
  26 #include "config.h"
  27 #endif
  28
  29 #include <tcpdump-stdinc.h>
  30
  31 #include "interface.h"
  32 #include "extract.h"
  33
  34 static const char tstr[] = " [|kerberos]";
  35
  36 static const u_char *c_print(netdissect_options *, register const u_char *, register const u_char *);
  37 static const u_char *krb4_print_hdr(netdissect_options *, const u_char *);
  38 static void krb4_print(netdissect_options *, const u_char *);
  39
  40 #define AUTH_MSG_KDC_REQUEST                    1<<1
  41 #define AUTH_MSG_KDC_REPLY                      2<<1
  42 #define AUTH_MSG_APPL_REQUEST                   3<<1
  43 #define AUTH_MSG_APPL_REQUEST_MUTUAL            4<<1
  44 #define AUTH_MSG_ERR_REPLY                      5<<1
  45 #define AUTH_MSG_PRIVATE                        6<<1
  46 #define AUTH_MSG_SAFE                           7<<1
  47 #define AUTH_MSG_APPL_ERR                       8<<1
  48 #define AUTH_MSG_DIE                            63<<1
  49
  50 #define KERB_ERR_OK                             0
  51 #define KERB_ERR_NAME_EXP                       1
  52 #define KERB_ERR_SERVICE_EXP                    2
  53 #define KERB_ERR_AUTH_EXP                       3
  54 #define KERB_ERR_PKT_VER                        4
  55 #define KERB_ERR_NAME_MAST_KEY_VER              5
  56 #define KERB_ERR_SERV_MAST_KEY_VER              6
  57 #define KERB_ERR_BYTE_ORDER                     7
  58 #define KERB_ERR_PRINCIPAL_UNKNOWN              8
  59 #define KERB_ERR_PRINCIPAL_NOT_UNIQUE           9
  60 #define KERB_ERR_NULL_KEY                       10
  61
  62 struct krb {
  63         uint8_t pvno;           /* Protocol Version */
  64         uint8_t type;           /* Type+B */
  65 };
  66
  67 static const struct tok type2str[] = {
  68         { AUTH_MSG_KDC_REQUEST,         "KDC_REQUEST" },
  69         { AUTH_MSG_KDC_REPLY,           "KDC_REPLY" },
  70         { AUTH_MSG_APPL_REQUEST,        "APPL_REQUEST" },
  71         { AUTH_MSG_APPL_REQUEST_MUTUAL, "APPL_REQUEST_MUTUAL" },
  72         { AUTH_MSG_ERR_REPLY,           "ERR_REPLY" },
  73         { AUTH_MSG_PRIVATE,             "PRIVATE" },
  74         { AUTH_MSG_SAFE,                "SAFE" },
  75         { AUTH_MSG_APPL_ERR,            "APPL_ERR" },
  76         { AUTH_MSG_DIE,                 "DIE" },
  77         { 0,                            NULL }
  78 };
  79
  80 static const struct tok kerr2str[] = {
  81         { KERB_ERR_OK,                  "OK" },
  82         { KERB_ERR_NAME_EXP,            "NAME_EXP" },
  83         { KERB_ERR_SERVICE_EXP,         "SERVICE_EXP" },
  84         { KERB_ERR_AUTH_EXP,            "AUTH_EXP" },
  85         { KERB_ERR_PKT_VER,             "PKT_VER" },
  86         { KERB_ERR_NAME_MAST_KEY_VER,   "NAME_MAST_KEY_VER" },
  87         { KERB_ERR_SERV_MAST_KEY_VER,   "SERV_MAST_KEY_VER" },
  88         { KERB_ERR_BYTE_ORDER,          "BYTE_ORDER" },
  89         { KERB_ERR_PRINCIPAL_UNKNOWN,   "PRINCIPAL_UNKNOWN" },
  90         { KERB_ERR_PRINCIPAL_NOT_UNIQUE,"PRINCIPAL_NOT_UNIQUE" },
  91         { KERB_ERR_NULL_KEY,            "NULL_KEY"},
  92         { 0,                            NULL}
  93 };
  94
  95 static const u_char *
  96 c_print(netdissect_options *ndo,
  97         register const u_char *s, register const u_char *ep)
  98 {
  99         register u_char c;
 100         register int flag;
 101
 102         flag = 1;
 103         while (s < ep) {
 104                 c = *s++;
 105                 if (c == '\0') {
 106                         flag = 0;
 107                         break;
 108                 }
 109                 if (!ND_ISASCII(c)) {
 110                         c = ND_TOASCII(c);
 111                         ND_PRINT((ndo, "M-"));
 112                 }
 113                 if (!ND_ISPRINT(c)) {
 114                         c ^= 0x40;      /* DEL to ?, others to alpha */
 115                         ND_PRINT((ndo, "^"));
 116                 }
 117                 ND_PRINT((ndo, "%c", c));
 118         }
 119         if (flag)
 120                 return NULL;
 121         return (s);
 122 }
 123
 124 static const u_char *
 125 krb4_print_hdr(netdissect_options *ndo,
 126                const u_char *cp)
 127 {
 128         cp += 2;
 129
 130 #define PRINT           if ((cp = c_print(ndo, cp, ndo->ndo_snapend)) == NULL) goto trunc
 131
 132         PRINT;
 133         ND_PRINT((ndo, "."));
 134         PRINT;
 135         ND_PRINT((ndo, "@"));
 136         PRINT;
 137         return (cp);
 138
 139 trunc:
 140         ND_PRINT((ndo, "%s", tstr));
 141         return (NULL);
 142
 143 #undef PRINT
 144 }
 145
 146 static void
 147 krb4_print(netdissect_options *ndo,
 148            const u_char *cp)
 149 {
 150         register const struct krb *kp;
 151         u_char type;
 152         u_short len;
 153
 154 #define PRINT           if ((cp = c_print(ndo, cp, ndo->ndo_snapend)) == NULL) goto trunc
 155 /*  True if struct krb is little endian */
 156 #define IS_LENDIAN(kp)  (((kp)->type & 0x01) != 0)
 157 #define KTOHSP(kp, cp)  (IS_LENDIAN(kp) ? EXTRACT_LE_16BITS(cp) : EXTRACT_16BITS(cp))
 158
 159         kp = (struct krb *)cp;
 160
 161         if ((&kp->type) >= ndo->ndo_snapend) {
 162                 ND_PRINT((ndo, "%s", tstr));
 163                 return;
 164         }
 165
 166         type = kp->type & (0xFF << 1);
 167
 168         ND_PRINT((ndo, " %s %s: ",
 169             IS_LENDIAN(kp) ? "le" : "be", tok2str(type2str, NULL, type)));
 170
 171         switch (type) {
 172
 173         case AUTH_MSG_KDC_REQUEST:
 174                 if ((cp = krb4_print_hdr(ndo, cp)) == NULL)
 175                         return;
 176                 cp += 4;        /* ctime */
 177                 ND_TCHECK(*cp);
 178                 ND_PRINT((ndo, " %dmin ", *cp++ * 5));
 179                 PRINT;
 180                 ND_PRINT((ndo, "."));
 181                 PRINT;
 182                 break;
 183
 184         case AUTH_MSG_APPL_REQUEST:
 185                 cp += 2;
 186                 ND_TCHECK(*cp);
 187                 ND_PRINT((ndo, "v%d ", *cp++));
 188                 PRINT;
 189                 ND_TCHECK(*cp);
 190                 ND_PRINT((ndo, " (%d)", *cp++));
 191                 ND_TCHECK(*cp);
 192                 ND_PRINT((ndo, " (%d)", *cp));
 193                 break;
 194
 195         case AUTH_MSG_KDC_REPLY:
 196                 if ((cp = krb4_print_hdr(ndo, cp)) == NULL)
 197                         return;
 198                 cp += 10;       /* timestamp + n + exp + kvno */
 199                 ND_TCHECK2(*cp, sizeof(short));
 200                 len = KTOHSP(kp, cp);
 201                 ND_PRINT((ndo, " (%d)", len));
 202                 break;
 203
 204         case AUTH_MSG_ERR_REPLY:
 205                 if ((cp = krb4_print_hdr(ndo, cp)) == NULL)
 206                         return;
 207                 cp += 4;          /* timestamp */
 208                 ND_TCHECK2(*cp, sizeof(short));
 209                 ND_PRINT((ndo, " %s ", tok2str(kerr2str, NULL, KTOHSP(kp, cp))));
 210                 cp += 4;
 211                 PRINT;
 212                 break;
 213
 214         default:
 215                 ND_PRINT((ndo, "(unknown)"));
 216                 break;
 217         }
 218
 219         return;
 220 trunc:
 221         ND_PRINT((ndo, "%s", tstr));
 222 }
 223
 224 void
 225 krb_print(netdissect_options *ndo,
 226           const u_char *dat)
 227 {
 228         register const struct krb *kp;
 229
 230         kp = (struct krb *)dat;
 231
 232         if (dat >= ndo->ndo_snapend) {
 233                 ND_PRINT((ndo, "%s", tstr));
 234                 return;
 235         }
 236
 237         switch (kp->pvno) {
 238
 239         case 1:
 240         case 2:
 241         case 3:
 242                 ND_PRINT((ndo, " v%d", kp->pvno));
 243                 break;
 244
 245         case 4:
 246                 ND_PRINT((ndo, " v%d", kp->pvno));
 247                 krb4_print(ndo, (const u_char *)kp);
 248                 break;
 249
 250         case 106:
 251         case 107:
 252                 ND_PRINT((ndo, " v5"));
 253                 /* Decode ASN.1 here "someday" */
 254                 break;
 255         }
 256         return;
 257 }