contrib/tcpdump/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 /* \summary: Kerberos printer */
  25
  26 #ifdef HAVE_CONFIG_H
  27 #include "config.h"
  28 #endif
  29
  30 #include <netdissect-stdinc.h>
  31
  32 #include "netdissect.h"
  33 #include "extract.h"
  34
  35 static const char tstr[] = " [|kerberos]";
  36
  37 static const u_char *c_print(netdissect_options *, register const u_char *, register const u_char *);
  38 static const u_char *krb4_print_hdr(netdissect_options *, const u_char *);
  39 static void krb4_print(netdissect_options *, const u_char *);
  40
  41 #define AUTH_MSG_KDC_REQUEST                    1<<1
  42 #define AUTH_MSG_KDC_REPLY                      2<<1
  43 #define AUTH_MSG_APPL_REQUEST                   3<<1
  44 #define AUTH_MSG_APPL_REQUEST_MUTUAL            4<<1
  45 #define AUTH_MSG_ERR_REPLY                      5<<1
  46 #define AUTH_MSG_PRIVATE                        6<<1
  47 #define AUTH_MSG_SAFE                           7<<1
  48 #define AUTH_MSG_APPL_ERR                       8<<1
  49 #define AUTH_MSG_DIE                            63<<1
  50
  51 #define KERB_ERR_OK                             0
  52 #define KERB_ERR_NAME_EXP                       1
  53 #define KERB_ERR_SERVICE_EXP                    2
  54 #define KERB_ERR_AUTH_EXP                       3
  55 #define KERB_ERR_PKT_VER                        4
  56 #define KERB_ERR_NAME_MAST_KEY_VER              5
  57 #define KERB_ERR_SERV_MAST_KEY_VER              6
  58 #define KERB_ERR_BYTE_ORDER                     7
  59 #define KERB_ERR_PRINCIPAL_UNKNOWN              8
  60 #define KERB_ERR_PRINCIPAL_NOT_UNIQUE           9
  61 #define KERB_ERR_NULL_KEY                       10
  62
  63 struct krb {
  64         uint8_t pvno;           /* Protocol Version */
  65         uint8_t type;           /* Type+B */
  66 };
  67
  68 static const struct tok type2str[] = {
  69         { AUTH_MSG_KDC_REQUEST,         "KDC_REQUEST" },
  70         { AUTH_MSG_KDC_REPLY,           "KDC_REPLY" },
  71         { AUTH_MSG_APPL_REQUEST,        "APPL_REQUEST" },
  72         { AUTH_MSG_APPL_REQUEST_MUTUAL, "APPL_REQUEST_MUTUAL" },
  73         { AUTH_MSG_ERR_REPLY,           "ERR_REPLY" },
  74         { AUTH_MSG_PRIVATE,             "PRIVATE" },
  75         { AUTH_MSG_SAFE,                "SAFE" },
  76         { AUTH_MSG_APPL_ERR,            "APPL_ERR" },
  77         { AUTH_MSG_DIE,                 "DIE" },
  78         { 0,                            NULL }
  79 };
  80
  81 static const struct tok kerr2str[] = {
  82         { KERB_ERR_OK,                  "OK" },
  83         { KERB_ERR_NAME_EXP,            "NAME_EXP" },
  84         { KERB_ERR_SERVICE_EXP,         "SERVICE_EXP" },
  85         { KERB_ERR_AUTH_EXP,            "AUTH_EXP" },
  86         { KERB_ERR_PKT_VER,             "PKT_VER" },
  87         { KERB_ERR_NAME_MAST_KEY_VER,   "NAME_MAST_KEY_VER" },
  88         { KERB_ERR_SERV_MAST_KEY_VER,   "SERV_MAST_KEY_VER" },
  89         { KERB_ERR_BYTE_ORDER,          "BYTE_ORDER" },
  90         { KERB_ERR_PRINCIPAL_UNKNOWN,   "PRINCIPAL_UNKNOWN" },
  91         { KERB_ERR_PRINCIPAL_NOT_UNIQUE,"PRINCIPAL_NOT_UNIQUE" },
  92         { KERB_ERR_NULL_KEY,            "NULL_KEY"},
  93         { 0,                            NULL}
  94 };
  95
  96 static const u_char *
  97 c_print(netdissect_options *ndo,
  98         register const u_char *s, register const u_char *ep)
  99 {
 100         register u_char c;
 101         register int flag;
 102
 103         flag = 1;
 104         while (s < ep) {
 105                 c = *s++;
 106                 if (c == '\0') {
 107                         flag = 0;
 108                         break;
 109                 }
 110                 if (!ND_ISASCII(c)) {
 111                         c = ND_TOASCII(c);
 112                         ND_PRINT((ndo, "M-"));
 113                 }
 114                 if (!ND_ISPRINT(c)) {
 115                         c ^= 0x40;      /* DEL to ?, others to alpha */
 116                         ND_PRINT((ndo, "^"));
 117                 }
 118                 ND_PRINT((ndo, "%c", c));
 119         }
 120         if (flag)
 121                 return NULL;
 122         return (s);
 123 }
 124
 125 static const u_char *
 126 krb4_print_hdr(netdissect_options *ndo,
 127                const u_char *cp)
 128 {
 129         cp += 2;
 130
 131 #define PRINT           if ((cp = c_print(ndo, cp, ndo->ndo_snapend)) == NULL) goto trunc
 132
 133         PRINT;
 134         ND_PRINT((ndo, "."));
 135         PRINT;
 136         ND_PRINT((ndo, "@"));
 137         PRINT;
 138         return (cp);
 139
 140 trunc:
 141         ND_PRINT((ndo, "%s", tstr));
 142         return (NULL);
 143
 144 #undef PRINT
 145 }
 146
 147 static void
 148 krb4_print(netdissect_options *ndo,
 149            const u_char *cp)
 150 {
 151         register const struct krb *kp;
 152         u_char type;
 153         u_short len;
 154
 155 #define PRINT           if ((cp = c_print(ndo, cp, ndo->ndo_snapend)) == NULL) goto trunc
 156 /*  True if struct krb is little endian */
 157 #define IS_LENDIAN(kp)  (((kp)->type & 0x01) != 0)
 158 #define KTOHSP(kp, cp)  (IS_LENDIAN(kp) ? EXTRACT_LE_16BITS(cp) : EXTRACT_16BITS(cp))
 159
 160         kp = (const struct krb *)cp;
 161
 162         if ((&kp->type) >= ndo->ndo_snapend) {
 163                 ND_PRINT((ndo, "%s", tstr));
 164                 return;
 165         }
 166
 167         type = kp->type & (0xFF << 1);
 168
 169         ND_PRINT((ndo, " %s %s: ",
 170             IS_LENDIAN(kp) ? "le" : "be", tok2str(type2str, NULL, type)));
 171
 172         switch (type) {
 173
 174         case AUTH_MSG_KDC_REQUEST:
 175                 if ((cp = krb4_print_hdr(ndo, cp)) == NULL)
 176                         return;
 177                 cp += 4;        /* ctime */
 178                 ND_TCHECK(*cp);
 179                 ND_PRINT((ndo, " %dmin ", *cp++ * 5));
 180                 PRINT;
 181                 ND_PRINT((ndo, "."));
 182                 PRINT;
 183                 break;
 184
 185         case AUTH_MSG_APPL_REQUEST:
 186                 cp += 2;
 187                 ND_TCHECK(*cp);
 188                 ND_PRINT((ndo, "v%d ", *cp++));
 189                 PRINT;
 190                 ND_TCHECK(*cp);
 191                 ND_PRINT((ndo, " (%d)", *cp++));
 192                 ND_TCHECK(*cp);
 193                 ND_PRINT((ndo, " (%d)", *cp));
 194                 break;
 195
 196         case AUTH_MSG_KDC_REPLY:
 197                 if ((cp = krb4_print_hdr(ndo, cp)) == NULL)
 198                         return;
 199                 cp += 10;       /* timestamp + n + exp + kvno */
 200                 ND_TCHECK2(*cp, sizeof(short));
 201                 len = KTOHSP(kp, cp);
 202                 ND_PRINT((ndo, " (%d)", len));
 203                 break;
 204
 205         case AUTH_MSG_ERR_REPLY:
 206                 if ((cp = krb4_print_hdr(ndo, cp)) == NULL)
 207                         return;
 208                 cp += 4;          /* timestamp */
 209                 ND_TCHECK2(*cp, sizeof(short));
 210                 ND_PRINT((ndo, " %s ", tok2str(kerr2str, NULL, KTOHSP(kp, cp))));
 211                 cp += 4;
 212                 PRINT;
 213                 break;
 214
 215         default:
 216                 ND_PRINT((ndo, "(unknown)"));
 217                 break;
 218         }
 219
 220         return;
 221 trunc:
 222         ND_PRINT((ndo, "%s", tstr));
 223 }
 224
 225 void
 226 krb_print(netdissect_options *ndo,
 227           const u_char *dat)
 228 {
 229         register const struct krb *kp;
 230
 231         kp = (const struct krb *)dat;
 232
 233         if (dat >= ndo->ndo_snapend) {
 234                 ND_PRINT((ndo, "%s", tstr));
 235                 return;
 236         }
 237
 238         switch (kp->pvno) {
 239
 240         case 1:
 241         case 2:
 242         case 3:
 243                 ND_PRINT((ndo, " v%d", kp->pvno));
 244                 break;
 245
 246         case 4:
 247                 ND_PRINT((ndo, " v%d", kp->pvno));
 248                 krb4_print(ndo, (const u_char *)kp);
 249                 break;
 250
 251         case 106:
 252         case 107:
 253                 ND_PRINT((ndo, " v5"));
 254                 /* Decode ASN.1 here "someday" */
 255                 break;
 256         }
 257         return;
 258 }