1 /*- 2 * Copyright (c) 1992, 1993 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 the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #ifndef lint 38 static char sccsid[] = "@(#)krb4encpwd.c 8.3 (Berkeley) 5/30/95"; 39 #endif /* not lint */ 40 41 42 #ifdef KRB4_ENCPWD 43 /* 44 * COPYRIGHT (C) 1990 DIGITAL EQUIPMENT CORPORATION 45 * ALL RIGHTS RESERVED 46 * 47 * "Digital Equipment Corporation authorizes the reproduction, 48 * distribution and modification of this software subject to the following 49 * restrictions: 50 * 51 * 1. Any partial or whole copy of this software, or any modification 52 * thereof, must include this copyright notice in its entirety. 53 * 54 * 2. This software is supplied "as is" with no warranty of any kind, 55 * expressed or implied, for any purpose, including any warranty of fitness 56 * or merchantibility. DIGITAL assumes no responsibility for the use or 57 * reliability of this software, nor promises to provide any form of 58 * support for it on any basis. 59 * 60 * 3. Distribution of this software is authorized only if no profit or 61 * remuneration of any kind is received in exchange for such distribution. 62 * 63 * 4. This software produces public key authentication certificates 64 * bearing an expiration date established by DIGITAL and RSA Data 65 * Security, Inc. It may cease to generate certificates after the expiration 66 * date. Any modification of this software that changes or defeats 67 * the expiration date or its effect is unauthorized. 68 * 69 * 5. Software that will renew or extend the expiration date of 70 * authentication certificates produced by this software may be obtained 71 * from RSA Data Security, Inc., 10 Twin Dolphin Drive, Redwood City, CA 72 * 94065, (415)595-8782, or from DIGITAL" 73 * 74 */ 75 76 #include <sys/types.h> 77 #include <arpa/telnet.h> 78 #include <pwd.h> 79 #include <stdio.h> 80 81 #include <openssl/des.h> 82 #include <krb.h> 83 #ifdef __STDC__ 84 #include <stdlib.h> 85 #endif 86 #ifdef NO_STRING_H 87 #include <strings.h> 88 #else 89 #include <string.h> 90 #endif 91 92 #include "encrypt.h" 93 #include "auth.h" 94 #include "misc.h" 95 96 int krb_mk_encpwd_req P((KTEXT, char *, char *, char *, char *, char *, char *)); 97 int krb_rd_encpwd_req P((KTEXT, char *, char *, u_long, AUTH_DAT *, char *, char *, char *, char *)); 98 99 extern auth_debug_mode; 100 101 static unsigned char str_data[1024] = { IAC, SB, TELOPT_AUTHENTICATION, 0, 102 AUTHTYPE_KRB4_ENCPWD, }; 103 static unsigned char str_name[1024] = { IAC, SB, TELOPT_AUTHENTICATION, 104 TELQUAL_NAME, }; 105 106 #define KRB4_ENCPWD_AUTH 0 /* Authentication data follows */ 107 #define KRB4_ENCPWD_REJECT 1 /* Rejected (reason might follow) */ 108 #define KRB4_ENCPWD_ACCEPT 2 /* Accepted */ 109 #define KRB4_ENCPWD_CHALLENGE 3 /* Challenge for mutual auth. */ 110 #define KRB4_ENCPWD_ACK 4 /* Acknowledge */ 111 112 #define KRB_SERVICE_NAME "rcmd" 113 114 static KTEXT_ST auth; 115 static char name[ANAME_SZ]; 116 static char user_passwd[ANAME_SZ]; 117 static AUTH_DAT adat = { 0 }; 118 #ifdef ENCRYPTION 119 static Block session_key = { 0 }; 120 #endif /* ENCRYPTION */ 121 static char challenge[REALM_SZ]; 122 123 static int 124 Data(ap, type, d, c) 125 Authenticator *ap; 126 int type; 127 void *d; 128 int c; 129 { 130 unsigned char *p = str_data + 4; 131 unsigned char *cd = (unsigned char *)d; 132 133 if (c == -1) 134 c = strlen((char *)cd); 135 136 if (0) { 137 printf("%s:%d: [%d] (%d)", 138 str_data[3] == TELQUAL_IS ? ">>>IS" : ">>>REPLY", 139 str_data[3], 140 type, c); 141 printd(d, c); 142 printf("\r\n"); 143 } 144 *p++ = ap->type; 145 *p++ = ap->way; 146 *p++ = type; 147 while (c-- > 0) { 148 if ((*p++ = *cd++) == IAC) 149 *p++ = IAC; 150 } 151 *p++ = IAC; 152 *p++ = SE; 153 if (str_data[3] == TELQUAL_IS) 154 printsub('>', &str_data[2], p - (&str_data[2])); 155 return(net_write(str_data, p - str_data)); 156 } 157 158 int 159 krb4encpwd_init(ap, server) 160 Authenticator *ap; 161 int server; 162 { 163 char hostname[80], *cp, *realm; 164 C_Block skey; 165 166 if (server) { 167 str_data[3] = TELQUAL_REPLY; 168 } else { 169 str_data[3] = TELQUAL_IS; 170 gethostname(hostname, sizeof(hostname)); 171 realm = krb_realmofhost(hostname); 172 cp = strchr(hostname, '.'); 173 if (*cp != NULL) *cp = NULL; 174 if (read_service_key(KRB_SERVICE_NAME, hostname, realm, 0, 175 KEYFILE, (char *)skey)) { 176 return(0); 177 } 178 } 179 return(1); 180 } 181 182 int 183 krb4encpwd_send(ap) 184 Authenticator *ap; 185 { 186 187 printf("[ Trying KRB4ENCPWD ... ]\n"); 188 if (!UserNameRequested) { 189 return(0); 190 } 191 if (!auth_sendname(UserNameRequested, strlen(UserNameRequested))) { 192 return(0); 193 } 194 195 if (!Data(ap, KRB4_ENCPWD_ACK, (void *)NULL, 0)) { 196 return(0); 197 } 198 199 return(1); 200 } 201 202 void 203 krb4encpwd_is(ap, data, cnt) 204 Authenticator *ap; 205 unsigned char *data; 206 int cnt; 207 { 208 Session_Key skey; 209 Block datablock; 210 char r_passwd[ANAME_SZ], r_user[ANAME_SZ]; 211 char lhostname[ANAME_SZ], *cp; 212 int r; 213 time_t now; 214 215 if (cnt-- < 1) 216 return; 217 switch (*data++) { 218 case KRB4_ENCPWD_AUTH: 219 memmove((void *)auth.dat, (void *)data, auth.length = cnt); 220 221 gethostname(lhostname, sizeof(lhostname)); 222 if ((cp = strchr(lhostname, '.')) != 0) *cp = '\0'; 223 224 if (r = krb_rd_encpwd_req(&auth, KRB_SERVICE_NAME, lhostname, 0, &adat, NULL, challenge, r_user, r_passwd)) { 225 Data(ap, KRB4_ENCPWD_REJECT, (void *)"Auth failed", -1); 226 auth_finished(ap, AUTH_REJECT); 227 return; 228 } 229 auth_encrypt_userpwd(r_passwd); 230 if (passwdok(UserNameRequested, UserPassword) == 0) { 231 /* 232 * illegal username and password 233 */ 234 Data(ap, KRB4_ENCPWD_REJECT, (void *)"Illegal password", -1); 235 auth_finished(ap, AUTH_REJECT); 236 return; 237 } 238 239 memmove((void *)session_key, (void *)adat.session, sizeof(Block)); 240 Data(ap, KRB4_ENCPWD_ACCEPT, (void *)0, 0); 241 auth_finished(ap, AUTH_USER); 242 break; 243 244 case KRB4_ENCPWD_CHALLENGE: 245 /* 246 * Take the received random challenge text and save 247 * for future authentication. 248 */ 249 memmove((void *)challenge, (void *)data, sizeof(Block)); 250 break; 251 252 253 case KRB4_ENCPWD_ACK: 254 /* 255 * Receive ack, if mutual then send random challenge 256 */ 257 258 /* 259 * If we are doing mutual authentication, get set up to send 260 * the challenge, and verify it when the response comes back. 261 */ 262 263 if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) { 264 register int i; 265 266 time(&now); 267 sprintf(challenge, "%x", now); 268 Data(ap, KRB4_ENCPWD_CHALLENGE, (void *)challenge, strlen(challenge)); 269 } 270 break; 271 272 default: 273 Data(ap, KRB4_ENCPWD_REJECT, 0, 0); 274 break; 275 } 276 } 277 278 279 void 280 krb4encpwd_reply(ap, data, cnt) 281 Authenticator *ap; 282 unsigned char *data; 283 int cnt; 284 { 285 Session_Key skey; 286 KTEXT_ST krb_token; 287 Block enckey; 288 CREDENTIALS cred; 289 int r; 290 char randchal[REALM_SZ], instance[ANAME_SZ], *cp; 291 char hostname[80], *realm; 292 293 if (cnt-- < 1) 294 return; 295 switch (*data++) { 296 case KRB4_ENCPWD_REJECT: 297 if (cnt > 0) { 298 printf("[ KRB4_ENCPWD refuses authentication because %.*s ]\r\n", 299 cnt, data); 300 } else 301 printf("[ KRB4_ENCPWD refuses authentication ]\r\n"); 302 auth_send_retry(); 303 return; 304 case KRB4_ENCPWD_ACCEPT: 305 printf("[ KRB4_ENCPWD accepts you ]\n"); 306 auth_finished(ap, AUTH_USER); 307 return; 308 case KRB4_ENCPWD_CHALLENGE: 309 /* 310 * Verify that the response to the challenge is correct. 311 */ 312 313 gethostname(hostname, sizeof(hostname)); 314 realm = krb_realmofhost(hostname); 315 memmove((void *)challenge, (void *)data, cnt); 316 memset(user_passwd, 0, sizeof(user_passwd)); 317 local_des_read_pw_string(user_passwd, sizeof(user_passwd)-1, "Password: ", 0); 318 UserPassword = user_passwd; 319 Challenge = challenge; 320 strcpy(instance, RemoteHostName); 321 if ((cp = strchr(instance, '.')) != 0) *cp = '\0'; 322 323 if (r = krb_mk_encpwd_req(&krb_token, KRB_SERVICE_NAME, instance, realm, Challenge, UserNameRequested, user_passwd)) { 324 krb_token.length = 0; 325 } 326 327 if (!Data(ap, KRB4_ENCPWD_AUTH, (void *)krb_token.dat, krb_token.length)) { 328 return; 329 } 330 331 break; 332 333 default: 334 return; 335 } 336 } 337 338 int 339 krb4encpwd_status(ap, name, level) 340 Authenticator *ap; 341 char *name; 342 int level; 343 { 344 345 if (level < AUTH_USER) 346 return(level); 347 348 if (UserNameRequested && passwdok(UserNameRequested, UserPassword)) { 349 strcpy(name, UserNameRequested); 350 return(AUTH_VALID); 351 } else { 352 return(AUTH_USER); 353 } 354 } 355 356 #define BUMP(buf, len) while (*(buf)) {++(buf), --(len);} 357 #define ADDC(buf, len, c) if ((len) > 0) {*(buf)++ = (c); --(len);} 358 359 void 360 krb4encpwd_printsub(data, cnt, buf, buflen) 361 unsigned char *data, *buf; 362 int cnt, buflen; 363 { 364 char lbuf[32]; 365 register int i; 366 367 buf[buflen-1] = '\0'; /* make sure its NULL terminated */ 368 buflen -= 1; 369 370 switch(data[3]) { 371 case KRB4_ENCPWD_REJECT: /* Rejected (reason might follow) */ 372 strncpy((char *)buf, " REJECT ", buflen); 373 goto common; 374 375 case KRB4_ENCPWD_ACCEPT: /* Accepted (name might follow) */ 376 strncpy((char *)buf, " ACCEPT ", buflen); 377 common: 378 BUMP(buf, buflen); 379 if (cnt <= 4) 380 break; 381 ADDC(buf, buflen, '"'); 382 for (i = 4; i < cnt; i++) 383 ADDC(buf, buflen, data[i]); 384 ADDC(buf, buflen, '"'); 385 ADDC(buf, buflen, '\0'); 386 break; 387 388 case KRB4_ENCPWD_AUTH: /* Authentication data follows */ 389 strncpy((char *)buf, " AUTH", buflen); 390 goto common2; 391 392 case KRB4_ENCPWD_CHALLENGE: 393 strncpy((char *)buf, " CHALLENGE", buflen); 394 goto common2; 395 396 case KRB4_ENCPWD_ACK: 397 strncpy((char *)buf, " ACK", buflen); 398 goto common2; 399 400 default: 401 sprintf(lbuf, " %d (unknown)", data[3]); 402 strncpy((char *)buf, lbuf, buflen); 403 common2: 404 BUMP(buf, buflen); 405 for (i = 4; i < cnt; i++) { 406 sprintf(lbuf, " %d", data[i]); 407 strncpy((char *)buf, lbuf, buflen); 408 BUMP(buf, buflen); 409 } 410 break; 411 } 412 } 413 414 int passwdok(name, passwd) 415 char *name, *passwd; 416 { 417 char *crypt(); 418 char *salt, *p; 419 struct passwd *pwd; 420 int passwdok_status = 0; 421 422 if (pwd = getpwnam(name)) 423 salt = pwd->pw_passwd; 424 else salt = "xx"; 425 426 p = crypt(passwd, salt); 427 428 if (pwd && !strcmp(p, pwd->pw_passwd)) { 429 passwdok_status = 1; 430 } else passwdok_status = 0; 431 return(passwdok_status); 432 } 433 434 #endif 435 436 #ifdef notdef 437 438 prkey(msg, key) 439 char *msg; 440 unsigned char *key; 441 { 442 register int i; 443 printf("%s:", msg); 444 for (i = 0; i < 8; i++) 445 printf(" %3d", key[i]); 446 printf("\r\n"); 447 } 448 #endif 449