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 * @(#)krb4encpwd.c 8.3 (Berkeley) 5/30/95 34 * $FreeBSD: src/crypto/telnet/libtelnet/krb4encpwd.c,v 1.3.2.1 2002/04/13 10:59:07 markm Exp $ 35 * $DragonFly: src/crypto/telnet/libtelnet/krb4encpwd.c,v 1.2 2003/06/17 04:24:37 dillon Exp $ 36 */ 37 38 #ifdef KRB4_ENCPWD 39 /* 40 * COPYRIGHT (C) 1990 DIGITAL EQUIPMENT CORPORATION 41 * ALL RIGHTS RESERVED 42 * 43 * "Digital Equipment Corporation authorizes the reproduction, 44 * distribution and modification of this software subject to the following 45 * restrictions: 46 * 47 * 1. Any partial or whole copy of this software, or any modification 48 * thereof, must include this copyright notice in its entirety. 49 * 50 * 2. This software is supplied "as is" with no warranty of any kind, 51 * expressed or implied, for any purpose, including any warranty of fitness 52 * or merchantibility. DIGITAL assumes no responsibility for the use or 53 * reliability of this software, nor promises to provide any form of 54 * support for it on any basis. 55 * 56 * 3. Distribution of this software is authorized only if no profit or 57 * remuneration of any kind is received in exchange for such distribution. 58 * 59 * 4. This software produces public key authentication certificates 60 * bearing an expiration date established by DIGITAL and RSA Data 61 * Security, Inc. It may cease to generate certificates after the expiration 62 * date. Any modification of this software that changes or defeats 63 * the expiration date or its effect is unauthorized. 64 * 65 * 5. Software that will renew or extend the expiration date of 66 * authentication certificates produced by this software may be obtained 67 * from RSA Data Security, Inc., 10 Twin Dolphin Drive, Redwood City, CA 68 * 94065, (415)595-8782, or from DIGITAL" 69 * 70 */ 71 72 #include <sys/types.h> 73 #include <openssl/des.h> 74 #include <arpa/telnet.h> 75 #include <krb.h> 76 #include <pwd.h> 77 #include <stdio.h> 78 #include <stdlib.h> 79 #include <string.h> 80 81 #include "encrypt.h" 82 #include "auth.h" 83 #include "misc.h" 84 85 int krb_mk_encpwd_req(KTEXT, char *, char *, char *, char *, char *, char *); 86 int krb_rd_encpwd_req(KTEXT, char *, char *, u_long, AUTH_DAT *, char *, char *, char *, char *); 87 88 extern auth_debug_mode; 89 90 static unsigned char str_data[1024] = { IAC, SB, TELOPT_AUTHENTICATION, 0, 91 AUTHTYPE_KRB4_ENCPWD, }; 92 static unsigned char str_name[1024] = { IAC, SB, TELOPT_AUTHENTICATION, 93 TELQUAL_NAME, }; 94 95 #define KRB4_ENCPWD_AUTH 0 /* Authentication data follows */ 96 #define KRB4_ENCPWD_REJECT 1 /* Rejected (reason might follow) */ 97 #define KRB4_ENCPWD_ACCEPT 2 /* Accepted */ 98 #define KRB4_ENCPWD_CHALLENGE 3 /* Challenge for mutual auth. */ 99 #define KRB4_ENCPWD_ACK 4 /* Acknowledge */ 100 101 #define KRB_SERVICE_NAME "rcmd" 102 103 static KTEXT_ST auth; 104 static char name[ANAME_SZ]; 105 static char user_passwd[ANAME_SZ]; 106 static AUTH_DAT adat = { 0 }; 107 #ifdef ENCRYPTION 108 static Block session_key = { 0 }; 109 #endif /* ENCRYPTION */ 110 static char challenge[REALM_SZ]; 111 112 static int 113 Data(ap, type, d, c) 114 Authenticator *ap; 115 int type; 116 void *d; 117 int c; 118 { 119 unsigned char *p = str_data + 4; 120 unsigned char *cd = (unsigned char *)d; 121 122 if (c == -1) 123 c = strlen((char *)cd); 124 125 if (0) { 126 printf("%s:%d: [%d] (%d)", 127 str_data[3] == TELQUAL_IS ? ">>>IS" : ">>>REPLY", 128 str_data[3], 129 type, c); 130 printd(d, c); 131 printf("\r\n"); 132 } 133 *p++ = ap->type; 134 *p++ = ap->way; 135 *p++ = type; 136 while (c-- > 0) { 137 if ((*p++ = *cd++) == IAC) 138 *p++ = IAC; 139 } 140 *p++ = IAC; 141 *p++ = SE; 142 if (str_data[3] == TELQUAL_IS) 143 printsub('>', &str_data[2], p - (&str_data[2])); 144 return(net_write(str_data, p - str_data)); 145 } 146 147 int 148 krb4encpwd_init(ap, server) 149 Authenticator *ap; 150 int server; 151 { 152 char hostname[80], *cp, *realm; 153 C_Block skey; 154 155 if (server) { 156 str_data[3] = TELQUAL_REPLY; 157 } else { 158 str_data[3] = TELQUAL_IS; 159 gethostname(hostname, sizeof(hostname)); 160 realm = krb_realmofhost(hostname); 161 cp = strchr(hostname, '.'); 162 if (*cp != NULL) *cp = NULL; 163 if (read_service_key(KRB_SERVICE_NAME, hostname, realm, 0, 164 KEYFILE, (char *)skey)) { 165 return(0); 166 } 167 } 168 return(1); 169 } 170 171 int 172 krb4encpwd_send(ap) 173 Authenticator *ap; 174 { 175 176 printf("[ Trying KRB4ENCPWD ... ]\n"); 177 if (!UserNameRequested) { 178 return(0); 179 } 180 if (!auth_sendname(UserNameRequested, strlen(UserNameRequested))) { 181 return(0); 182 } 183 184 if (!Data(ap, KRB4_ENCPWD_ACK, (void *)NULL, 0)) { 185 return(0); 186 } 187 188 return(1); 189 } 190 191 void 192 krb4encpwd_is(ap, data, cnt) 193 Authenticator *ap; 194 unsigned char *data; 195 int cnt; 196 { 197 Session_Key skey; 198 Block datablock; 199 char r_passwd[ANAME_SZ], r_user[ANAME_SZ]; 200 char lhostname[ANAME_SZ], *cp; 201 int r; 202 time_t now; 203 204 if (cnt-- < 1) 205 return; 206 switch (*data++) { 207 case KRB4_ENCPWD_AUTH: 208 memmove((void *)auth.dat, (void *)data, auth.length = cnt); 209 210 gethostname(lhostname, sizeof(lhostname)); 211 if ((cp = strchr(lhostname, '.')) != 0) *cp = '\0'; 212 213 if (r = krb_rd_encpwd_req(&auth, KRB_SERVICE_NAME, lhostname, 0, &adat, NULL, challenge, r_user, r_passwd)) { 214 Data(ap, KRB4_ENCPWD_REJECT, (void *)"Auth failed", -1); 215 auth_finished(ap, AUTH_REJECT); 216 return; 217 } 218 auth_encrypt_userpwd(r_passwd); 219 if (passwdok(UserNameRequested, UserPassword) == 0) { 220 /* 221 * illegal username and password 222 */ 223 Data(ap, KRB4_ENCPWD_REJECT, (void *)"Illegal password", -1); 224 auth_finished(ap, AUTH_REJECT); 225 return; 226 } 227 228 memmove((void *)session_key, (void *)adat.session, sizeof(Block)); 229 Data(ap, KRB4_ENCPWD_ACCEPT, (void *)0, 0); 230 auth_finished(ap, AUTH_USER); 231 break; 232 233 case KRB4_ENCPWD_CHALLENGE: 234 /* 235 * Take the received random challenge text and save 236 * for future authentication. 237 */ 238 memmove((void *)challenge, (void *)data, sizeof(Block)); 239 break; 240 241 242 case KRB4_ENCPWD_ACK: 243 /* 244 * Receive ack, if mutual then send random challenge 245 */ 246 247 /* 248 * If we are doing mutual authentication, get set up to send 249 * the challenge, and verify it when the response comes back. 250 */ 251 252 if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) { 253 register int i; 254 255 time(&now); 256 sprintf(challenge, "%x", now); 257 Data(ap, KRB4_ENCPWD_CHALLENGE, (void *)challenge, strlen(challenge)); 258 } 259 break; 260 261 default: 262 Data(ap, KRB4_ENCPWD_REJECT, 0, 0); 263 break; 264 } 265 } 266 267 268 void 269 krb4encpwd_reply(ap, data, cnt) 270 Authenticator *ap; 271 unsigned char *data; 272 int cnt; 273 { 274 Session_Key skey; 275 KTEXT_ST krb_token; 276 Block enckey; 277 CREDENTIALS cred; 278 int r; 279 char randchal[REALM_SZ], instance[ANAME_SZ], *cp; 280 char hostname[80], *realm; 281 282 if (cnt-- < 1) 283 return; 284 switch (*data++) { 285 case KRB4_ENCPWD_REJECT: 286 if (cnt > 0) { 287 printf("[ KRB4_ENCPWD refuses authentication because %.*s ]\r\n", 288 cnt, data); 289 } else 290 printf("[ KRB4_ENCPWD refuses authentication ]\r\n"); 291 auth_send_retry(); 292 return; 293 case KRB4_ENCPWD_ACCEPT: 294 printf("[ KRB4_ENCPWD accepts you ]\n"); 295 auth_finished(ap, AUTH_USER); 296 return; 297 case KRB4_ENCPWD_CHALLENGE: 298 /* 299 * Verify that the response to the challenge is correct. 300 */ 301 302 gethostname(hostname, sizeof(hostname)); 303 realm = krb_realmofhost(hostname); 304 memmove((void *)challenge, (void *)data, cnt); 305 memset(user_passwd, 0, sizeof(user_passwd)); 306 local_des_read_pw_string(user_passwd, sizeof(user_passwd)-1, "Password: ", 0); 307 UserPassword = user_passwd; 308 Challenge = challenge; 309 strcpy(instance, RemoteHostName); 310 if ((cp = strchr(instance, '.')) != 0) *cp = '\0'; 311 312 if (r = krb_mk_encpwd_req(&krb_token, KRB_SERVICE_NAME, instance, realm, Challenge, UserNameRequested, user_passwd)) { 313 krb_token.length = 0; 314 } 315 316 if (!Data(ap, KRB4_ENCPWD_AUTH, (void *)krb_token.dat, krb_token.length)) { 317 return; 318 } 319 320 break; 321 322 default: 323 return; 324 } 325 } 326 327 int 328 krb4encpwd_status(ap, name, level) 329 Authenticator *ap; 330 char *name; 331 int level; 332 { 333 334 if (level < AUTH_USER) 335 return(level); 336 337 if (UserNameRequested && passwdok(UserNameRequested, UserPassword)) { 338 strcpy(name, UserNameRequested); 339 return(AUTH_VALID); 340 } else { 341 return(AUTH_USER); 342 } 343 } 344 345 #define BUMP(buf, len) while (*(buf)) {++(buf), --(len);} 346 #define ADDC(buf, len, c) if ((len) > 0) {*(buf)++ = (c); --(len);} 347 348 void 349 krb4encpwd_printsub(data, cnt, buf, buflen) 350 unsigned char *data, *buf; 351 int cnt, buflen; 352 { 353 char lbuf[32]; 354 register int i; 355 356 buf[buflen-1] = '\0'; /* make sure its NULL terminated */ 357 buflen -= 1; 358 359 switch(data[3]) { 360 case KRB4_ENCPWD_REJECT: /* Rejected (reason might follow) */ 361 strncpy((char *)buf, " REJECT ", buflen); 362 goto common; 363 364 case KRB4_ENCPWD_ACCEPT: /* Accepted (name might follow) */ 365 strncpy((char *)buf, " ACCEPT ", buflen); 366 common: 367 BUMP(buf, buflen); 368 if (cnt <= 4) 369 break; 370 ADDC(buf, buflen, '"'); 371 for (i = 4; i < cnt; i++) 372 ADDC(buf, buflen, data[i]); 373 ADDC(buf, buflen, '"'); 374 ADDC(buf, buflen, '\0'); 375 break; 376 377 case KRB4_ENCPWD_AUTH: /* Authentication data follows */ 378 strncpy((char *)buf, " AUTH", buflen); 379 goto common2; 380 381 case KRB4_ENCPWD_CHALLENGE: 382 strncpy((char *)buf, " CHALLENGE", buflen); 383 goto common2; 384 385 case KRB4_ENCPWD_ACK: 386 strncpy((char *)buf, " ACK", buflen); 387 goto common2; 388 389 default: 390 sprintf(lbuf, " %d (unknown)", data[3]); 391 strncpy((char *)buf, lbuf, buflen); 392 common2: 393 BUMP(buf, buflen); 394 for (i = 4; i < cnt; i++) { 395 sprintf(lbuf, " %d", data[i]); 396 strncpy((char *)buf, lbuf, buflen); 397 BUMP(buf, buflen); 398 } 399 break; 400 } 401 } 402 403 int passwdok(name, passwd) 404 char *name, *passwd; 405 { 406 char *crypt(); 407 char *salt, *p; 408 struct passwd *pwd; 409 int passwdok_status = 0; 410 411 if (pwd = getpwnam(name)) 412 salt = pwd->pw_passwd; 413 else salt = "xx"; 414 415 p = crypt(passwd, salt); 416 417 if (pwd && !strcmp(p, pwd->pw_passwd)) { 418 passwdok_status = 1; 419 } else passwdok_status = 0; 420 return(passwdok_status); 421 } 422 423 #endif 424