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