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 1.9 2024/09/02 16:15:31 christos Exp $"); 27 #endif 28 29 /* \summary: Kerberos printer */ 30 31 #include <config.h> 32 33 #include "netdissect-stdinc.h" 34 35 #include "netdissect.h" 36 #include "extract.h" 37 38 /* 39 * Kerberos 4: 40 * 41 * Athena Technical Plan 42 * Section E.2.1 43 * Kerberos Authentication and Authorization System 44 * by S. P. Miller, B. C. Neuman, J. I. Schiller, and J. H. Saltzer 45 * 46 * https://web.mit.edu/Saltzer/www/publications/athenaplan/e.2.1.pdf 47 * 48 * 7. Appendix I Design Specifications 49 * 50 * Kerberos 5: 51 * 52 * RFC 1510, RFC 2630, etc. 53 */ 54 55 56 static const u_char *c_print(netdissect_options *, const u_char *, const u_char *); 57 static const u_char *krb4_print_hdr(netdissect_options *, const u_char *); 58 static void krb4_print(netdissect_options *, const u_char *); 59 60 #define AUTH_MSG_KDC_REQUEST 1<<1 61 #define AUTH_MSG_KDC_REPLY 2<<1 62 #define AUTH_MSG_APPL_REQUEST 3<<1 63 #define AUTH_MSG_APPL_REQUEST_MUTUAL 4<<1 64 #define AUTH_MSG_ERR_REPLY 5<<1 65 #define AUTH_MSG_PRIVATE 6<<1 66 #define AUTH_MSG_SAFE 7<<1 67 #define AUTH_MSG_APPL_ERR 8<<1 68 #define AUTH_MSG_DIE 63<<1 69 70 #define KERB_ERR_OK 0 71 #define KERB_ERR_NAME_EXP 1 72 #define KERB_ERR_SERVICE_EXP 2 73 #define KERB_ERR_AUTH_EXP 3 74 #define KERB_ERR_PKT_VER 4 75 #define KERB_ERR_NAME_MAST_KEY_VER 5 76 #define KERB_ERR_SERV_MAST_KEY_VER 6 77 #define KERB_ERR_BYTE_ORDER 7 78 #define KERB_ERR_PRINCIPAL_UNKNOWN 8 79 #define KERB_ERR_PRINCIPAL_NOT_UNIQUE 9 80 #define KERB_ERR_NULL_KEY 10 81 82 struct krb { 83 nd_uint8_t pvno; /* Protocol Version */ 84 nd_uint8_t type; /* Type+B */ 85 }; 86 87 static const struct tok type2str[] = { 88 { AUTH_MSG_KDC_REQUEST, "KDC_REQUEST" }, 89 { AUTH_MSG_KDC_REPLY, "KDC_REPLY" }, 90 { AUTH_MSG_APPL_REQUEST, "APPL_REQUEST" }, 91 { AUTH_MSG_APPL_REQUEST_MUTUAL, "APPL_REQUEST_MUTUAL" }, 92 { AUTH_MSG_ERR_REPLY, "ERR_REPLY" }, 93 { AUTH_MSG_PRIVATE, "PRIVATE" }, 94 { AUTH_MSG_SAFE, "SAFE" }, 95 { AUTH_MSG_APPL_ERR, "APPL_ERR" }, 96 { AUTH_MSG_DIE, "DIE" }, 97 { 0, NULL } 98 }; 99 100 static const struct tok kerr2str[] = { 101 { KERB_ERR_OK, "OK" }, 102 { KERB_ERR_NAME_EXP, "NAME_EXP" }, 103 { KERB_ERR_SERVICE_EXP, "SERVICE_EXP" }, 104 { KERB_ERR_AUTH_EXP, "AUTH_EXP" }, 105 { KERB_ERR_PKT_VER, "PKT_VER" }, 106 { KERB_ERR_NAME_MAST_KEY_VER, "NAME_MAST_KEY_VER" }, 107 { KERB_ERR_SERV_MAST_KEY_VER, "SERV_MAST_KEY_VER" }, 108 { KERB_ERR_BYTE_ORDER, "BYTE_ORDER" }, 109 { KERB_ERR_PRINCIPAL_UNKNOWN, "PRINCIPAL_UNKNOWN" }, 110 { KERB_ERR_PRINCIPAL_NOT_UNIQUE,"PRINCIPAL_NOT_UNIQUE" }, 111 { KERB_ERR_NULL_KEY, "NULL_KEY"}, 112 { 0, NULL} 113 }; 114 115 static const u_char * 116 c_print(netdissect_options *ndo, 117 const u_char *s, const u_char *ep) 118 { 119 u_char c; 120 int flag; 121 122 flag = 1; 123 while (s < ep) { 124 c = GET_U_1(s); 125 s++; 126 if (c == '\0') { 127 flag = 0; 128 break; 129 } 130 fn_print_char(ndo, c); 131 } 132 if (flag) 133 return NULL; 134 return (s); 135 } 136 137 static const u_char * 138 krb4_print_hdr(netdissect_options *ndo, 139 const u_char *cp) 140 { 141 cp += 2; 142 143 #define PRINT if ((cp = c_print(ndo, cp, ndo->ndo_snapend)) == NULL) goto trunc 144 145 PRINT; 146 ND_PRINT("."); 147 PRINT; 148 ND_PRINT("@"); 149 PRINT; 150 return (cp); 151 152 trunc: 153 nd_print_trunc(ndo); 154 return (NULL); 155 156 #undef PRINT 157 } 158 159 static void 160 krb4_print(netdissect_options *ndo, 161 const u_char *cp) 162 { 163 const struct krb *kp; 164 u_char type; 165 u_short len; 166 167 #define PRINT if ((cp = c_print(ndo, cp, ndo->ndo_snapend)) == NULL) goto trunc 168 /* True if struct krb is little endian */ 169 #define IS_LENDIAN(kp) ((GET_U_1((kp)->type) & 0x01) != 0) 170 #define KTOHSP(kp, cp) (IS_LENDIAN(kp) ? GET_LE_U_2(cp) : GET_BE_U_2(cp)) 171 172 kp = (const struct krb *)cp; 173 174 type = GET_U_1(kp->type) & (0xFF << 1); 175 176 ND_PRINT(" %s %s: ", 177 IS_LENDIAN(kp) ? "le" : "be", tok2str(type2str, NULL, type)); 178 179 switch (type) { 180 181 case AUTH_MSG_KDC_REQUEST: 182 if ((cp = krb4_print_hdr(ndo, cp)) == NULL) 183 return; 184 cp += 4; /* ctime */ 185 ND_PRINT(" %umin ", GET_U_1(cp) * 5); 186 cp++; 187 PRINT; 188 ND_PRINT("."); 189 PRINT; 190 break; 191 192 case AUTH_MSG_APPL_REQUEST: 193 cp += 2; 194 ND_PRINT("v%u ", GET_U_1(cp)); 195 cp++; 196 PRINT; 197 ND_PRINT(" (%u)", GET_U_1(cp)); 198 cp++; 199 ND_PRINT(" (%u)", GET_U_1(cp)); 200 break; 201 202 case AUTH_MSG_KDC_REPLY: 203 if ((cp = krb4_print_hdr(ndo, cp)) == NULL) 204 return; 205 cp += 10; /* timestamp + n + exp + kvno */ 206 len = KTOHSP(kp, cp); 207 ND_PRINT(" (%u)", len); 208 break; 209 210 case AUTH_MSG_ERR_REPLY: 211 if ((cp = krb4_print_hdr(ndo, cp)) == NULL) 212 return; 213 cp += 4; /* timestamp */ 214 ND_PRINT(" %s ", tok2str(kerr2str, NULL, KTOHSP(kp, cp))); 215 cp += 4; 216 PRINT; 217 break; 218 219 default: 220 ND_PRINT("(unknown)"); 221 break; 222 } 223 224 return; 225 trunc: 226 nd_print_trunc(ndo); 227 } 228 229 void 230 krb_print(netdissect_options *ndo, 231 const u_char *dat) 232 { 233 const struct krb *kp; 234 235 ndo->ndo_protocol = "kerberos"; 236 nd_print_protocol(ndo); 237 238 kp = (const struct krb *)dat; 239 240 switch (GET_U_1(kp->pvno)) { 241 242 case 1: 243 case 2: 244 case 3: 245 ND_PRINT(" v%u", GET_U_1(kp->pvno)); 246 break; 247 248 case 4: 249 ND_PRINT(" v%u", GET_U_1(kp->pvno)); 250 krb4_print(ndo, (const u_char *)kp); 251 break; 252 253 case 106: 254 case 107: 255 ND_PRINT(" v5"); 256 /* Decode ASN.1 here "someday" */ 257 break; 258 } 259 } 260