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 } 258