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 #include <sys/cdefs.h> 25 #ifndef lint 26 __RCSID("$NetBSD: print-krb.c,v 1.8 2023/08/17 20:19:40 christos Exp $"); 27 #endif 28 29 /* \summary: Kerberos printer */ 30 31 #ifdef HAVE_CONFIG_H 32 #include <config.h> 33 #endif 34 35 #include "netdissect-stdinc.h" 36 37 #include "netdissect.h" 38 #include "extract.h" 39 40 /* 41 * Kerberos 4: 42 * 43 * Athena Technical Plan 44 * Section E.2.1 45 * Kerberos Authentication and Authorization System 46 * by S. P. Miller, B. C. Neuman, J. I. Schiller, and J. H. Saltzer 47 * 48 * https://web.mit.edu/Saltzer/www/publications/athenaplan/e.2.1.pdf 49 * 50 * 7. Appendix I Design Specifications 51 * 52 * Kerberos 5: 53 * 54 * RFC 1510, RFC 2630, etc. 55 */ 56 57 58 static const u_char *c_print(netdissect_options *, const u_char *, const u_char *); 59 static const u_char *krb4_print_hdr(netdissect_options *, const u_char *); 60 static void krb4_print(netdissect_options *, const u_char *); 61 62 #define AUTH_MSG_KDC_REQUEST 1<<1 63 #define AUTH_MSG_KDC_REPLY 2<<1 64 #define AUTH_MSG_APPL_REQUEST 3<<1 65 #define AUTH_MSG_APPL_REQUEST_MUTUAL 4<<1 66 #define AUTH_MSG_ERR_REPLY 5<<1 67 #define AUTH_MSG_PRIVATE 6<<1 68 #define AUTH_MSG_SAFE 7<<1 69 #define AUTH_MSG_APPL_ERR 8<<1 70 #define AUTH_MSG_DIE 63<<1 71 72 #define KERB_ERR_OK 0 73 #define KERB_ERR_NAME_EXP 1 74 #define KERB_ERR_SERVICE_EXP 2 75 #define KERB_ERR_AUTH_EXP 3 76 #define KERB_ERR_PKT_VER 4 77 #define KERB_ERR_NAME_MAST_KEY_VER 5 78 #define KERB_ERR_SERV_MAST_KEY_VER 6 79 #define KERB_ERR_BYTE_ORDER 7 80 #define KERB_ERR_PRINCIPAL_UNKNOWN 8 81 #define KERB_ERR_PRINCIPAL_NOT_UNIQUE 9 82 #define KERB_ERR_NULL_KEY 10 83 84 struct krb { 85 nd_uint8_t pvno; /* Protocol Version */ 86 nd_uint8_t type; /* Type+B */ 87 }; 88 89 static const struct tok type2str[] = { 90 { AUTH_MSG_KDC_REQUEST, "KDC_REQUEST" }, 91 { AUTH_MSG_KDC_REPLY, "KDC_REPLY" }, 92 { AUTH_MSG_APPL_REQUEST, "APPL_REQUEST" }, 93 { AUTH_MSG_APPL_REQUEST_MUTUAL, "APPL_REQUEST_MUTUAL" }, 94 { AUTH_MSG_ERR_REPLY, "ERR_REPLY" }, 95 { AUTH_MSG_PRIVATE, "PRIVATE" }, 96 { AUTH_MSG_SAFE, "SAFE" }, 97 { AUTH_MSG_APPL_ERR, "APPL_ERR" }, 98 { AUTH_MSG_DIE, "DIE" }, 99 { 0, NULL } 100 }; 101 102 static const struct tok kerr2str[] = { 103 { KERB_ERR_OK, "OK" }, 104 { KERB_ERR_NAME_EXP, "NAME_EXP" }, 105 { KERB_ERR_SERVICE_EXP, "SERVICE_EXP" }, 106 { KERB_ERR_AUTH_EXP, "AUTH_EXP" }, 107 { KERB_ERR_PKT_VER, "PKT_VER" }, 108 { KERB_ERR_NAME_MAST_KEY_VER, "NAME_MAST_KEY_VER" }, 109 { KERB_ERR_SERV_MAST_KEY_VER, "SERV_MAST_KEY_VER" }, 110 { KERB_ERR_BYTE_ORDER, "BYTE_ORDER" }, 111 { KERB_ERR_PRINCIPAL_UNKNOWN, "PRINCIPAL_UNKNOWN" }, 112 { KERB_ERR_PRINCIPAL_NOT_UNIQUE,"PRINCIPAL_NOT_UNIQUE" }, 113 { KERB_ERR_NULL_KEY, "NULL_KEY"}, 114 { 0, NULL} 115 }; 116 117 static const u_char * 118 c_print(netdissect_options *ndo, 119 const u_char *s, const u_char *ep) 120 { 121 u_char c; 122 int flag; 123 124 flag = 1; 125 while (s < ep) { 126 c = GET_U_1(s); 127 s++; 128 if (c == '\0') { 129 flag = 0; 130 break; 131 } 132 fn_print_char(ndo, c); 133 } 134 if (flag) 135 return NULL; 136 return (s); 137 } 138 139 static const u_char * 140 krb4_print_hdr(netdissect_options *ndo, 141 const u_char *cp) 142 { 143 cp += 2; 144 145 #define PRINT if ((cp = c_print(ndo, cp, ndo->ndo_snapend)) == NULL) goto trunc 146 147 PRINT; 148 ND_PRINT("."); 149 PRINT; 150 ND_PRINT("@"); 151 PRINT; 152 return (cp); 153 154 trunc: 155 nd_print_trunc(ndo); 156 return (NULL); 157 158 #undef PRINT 159 } 160 161 static void 162 krb4_print(netdissect_options *ndo, 163 const u_char *cp) 164 { 165 const struct krb *kp; 166 u_char type; 167 u_short len; 168 169 #define PRINT if ((cp = c_print(ndo, cp, ndo->ndo_snapend)) == NULL) goto trunc 170 /* True if struct krb is little endian */ 171 #define IS_LENDIAN(kp) ((GET_U_1((kp)->type) & 0x01) != 0) 172 #define KTOHSP(kp, cp) (IS_LENDIAN(kp) ? GET_LE_U_2(cp) : GET_BE_U_2(cp)) 173 174 kp = (const struct krb *)cp; 175 176 type = GET_U_1(kp->type) & (0xFF << 1); 177 178 ND_PRINT(" %s %s: ", 179 IS_LENDIAN(kp) ? "le" : "be", tok2str(type2str, NULL, type)); 180 181 switch (type) { 182 183 case AUTH_MSG_KDC_REQUEST: 184 if ((cp = krb4_print_hdr(ndo, cp)) == NULL) 185 return; 186 cp += 4; /* ctime */ 187 ND_PRINT(" %umin ", GET_U_1(cp) * 5); 188 cp++; 189 PRINT; 190 ND_PRINT("."); 191 PRINT; 192 break; 193 194 case AUTH_MSG_APPL_REQUEST: 195 cp += 2; 196 ND_PRINT("v%u ", GET_U_1(cp)); 197 cp++; 198 PRINT; 199 ND_PRINT(" (%u)", GET_U_1(cp)); 200 cp++; 201 ND_PRINT(" (%u)", GET_U_1(cp)); 202 break; 203 204 case AUTH_MSG_KDC_REPLY: 205 if ((cp = krb4_print_hdr(ndo, cp)) == NULL) 206 return; 207 cp += 10; /* timestamp + n + exp + kvno */ 208 len = KTOHSP(kp, cp); 209 ND_PRINT(" (%u)", len); 210 break; 211 212 case AUTH_MSG_ERR_REPLY: 213 if ((cp = krb4_print_hdr(ndo, cp)) == NULL) 214 return; 215 cp += 4; /* timestamp */ 216 ND_PRINT(" %s ", tok2str(kerr2str, NULL, KTOHSP(kp, cp))); 217 cp += 4; 218 PRINT; 219 break; 220 221 default: 222 ND_PRINT("(unknown)"); 223 break; 224 } 225 226 return; 227 trunc: 228 nd_print_trunc(ndo); 229 } 230 231 void 232 krb_print(netdissect_options *ndo, 233 const u_char *dat) 234 { 235 const struct krb *kp; 236 237 ndo->ndo_protocol = "krb"; 238 kp = (const struct krb *)dat; 239 240 if (dat >= ndo->ndo_snapend) { 241 nd_print_trunc(ndo); 242 return; 243 } 244 245 switch (GET_U_1(kp->pvno)) { 246 247 case 1: 248 case 2: 249 case 3: 250 ND_PRINT(" v%u", GET_U_1(kp->pvno)); 251 break; 252 253 case 4: 254 ND_PRINT(" v%u", GET_U_1(kp->pvno)); 255 krb4_print(ndo, (const u_char *)kp); 256 break; 257 258 case 106: 259 case 107: 260 ND_PRINT(" v5"); 261 /* Decode ASN.1 here "someday" */ 262 break; 263 } 264 } 265