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 * @(#)rsaencpwd.c 8.3 (Berkeley) 5/30/95 34 * $FreeBSD: src/crypto/telnet/libtelnet/rsaencpwd.c,v 1.1.1.1.8.1 2002/04/13 10:59:07 markm Exp $ 35 * $DragonFly: src/crypto/telnet/libtelnet/rsaencpwd.c,v 1.2 2003/06/17 04:24:37 dillon Exp $ 36 */ 37 38 #ifdef RSA_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 <arpa/telnet.h> 74 #include <pwd.h> 75 #include <stdio.h> 76 #include <stdlib.h> 77 #include <string.h> 78 79 #include "encrypt.h" 80 #include "auth.h" 81 #include "misc.h" 82 #include "cdc.h" 83 84 extern auth_debug_mode; 85 86 static unsigned char str_data[1024] = { IAC, SB, TELOPT_AUTHENTICATION, 0, 87 AUTHTYPE_RSA_ENCPWD, }; 88 static unsigned char str_name[1024] = { IAC, SB, TELOPT_AUTHENTICATION, 89 TELQUAL_NAME, }; 90 91 #define RSA_ENCPWD_AUTH 0 /* Authentication data follows */ 92 #define RSA_ENCPWD_REJECT 1 /* Rejected (reason might follow) */ 93 #define RSA_ENCPWD_ACCEPT 2 /* Accepted */ 94 #define RSA_ENCPWD_CHALLENGEKEY 3 /* Challenge and public key */ 95 96 #define NAME_SZ 40 97 #define CHAL_SZ 20 98 #define PWD_SZ 40 99 100 static KTEXT_ST auth; 101 static char name[NAME_SZ]; 102 static char user_passwd[PWD_SZ]; 103 static char key_file[2*NAME_SZ]; 104 static char lhostname[NAME_SZ]; 105 static char challenge[CHAL_SZ]; 106 static int challenge_len; 107 108 static int 109 Data(ap, type, d, c) 110 Authenticator *ap; 111 int type; 112 void *d; 113 int c; 114 { 115 unsigned char *p = str_data + 4; 116 unsigned char *cd = (unsigned char *)d; 117 118 if (c == -1) 119 c = strlen((char *)cd); 120 121 if (0) { 122 printf("%s:%d: [%d] (%d)", 123 str_data[3] == TELQUAL_IS ? ">>>IS" : ">>>REPLY", 124 str_data[3], 125 type, c); 126 printd(d, c); 127 printf("\r\n"); 128 } 129 *p++ = ap->type; 130 *p++ = ap->way; 131 if (type != NULL) *p++ = type; 132 while (c-- > 0) { 133 if ((*p++ = *cd++) == IAC) 134 *p++ = IAC; 135 } 136 *p++ = IAC; 137 *p++ = SE; 138 if (str_data[3] == TELQUAL_IS) 139 printsub('>', &str_data[2], p - (&str_data[2])); 140 return(net_write(str_data, p - str_data)); 141 } 142 143 int 144 rsaencpwd_init(ap, server) 145 Authenticator *ap; 146 int server; 147 { 148 char *cp; 149 FILE *fp; 150 151 if (server) { 152 str_data[3] = TELQUAL_REPLY; 153 memset(key_file, 0, sizeof(key_file)); 154 gethostname(lhostname, sizeof(lhostname)); 155 if ((cp = strchr(lhostname, '.')) != 0) *cp = '\0'; 156 strcpy(key_file, "/etc/."); 157 strcat(key_file, lhostname); 158 strcat(key_file, "_privkey"); 159 if ((fp=fopen(key_file, "r"))==NULL) return(0); 160 fclose(fp); 161 } else { 162 str_data[3] = TELQUAL_IS; 163 } 164 return(1); 165 } 166 167 int 168 rsaencpwd_send(ap) 169 Authenticator *ap; 170 { 171 172 printf("[ Trying RSAENCPWD ... ]\n"); 173 if (!UserNameRequested) { 174 return(0); 175 } 176 if (!auth_sendname(UserNameRequested, strlen(UserNameRequested))) { 177 return(0); 178 } 179 if (!Data(ap, NULL, (void *)NULL, 0)) { 180 return(0); 181 } 182 183 184 return(1); 185 } 186 187 void 188 rsaencpwd_is(ap, data, cnt) 189 Authenticator *ap; 190 unsigned char *data; 191 int cnt; 192 { 193 Session_Key skey; 194 Block datablock; 195 char r_passwd[PWD_SZ], r_user[NAME_SZ]; 196 char *cp, key[160]; 197 char chalkey[160], *ptr; 198 FILE *fp; 199 int r, i, j, chalkey_len, len; 200 time_t now; 201 202 cnt--; 203 switch (*data++) { 204 case RSA_ENCPWD_AUTH: 205 memmove((void *)auth.dat, (void *)data, auth.length = cnt); 206 207 if ((fp=fopen(key_file, "r"))==NULL) { 208 Data(ap, RSA_ENCPWD_REJECT, (void *)"Auth failed", -1); 209 auth_finished(ap, AUTH_REJECT); 210 return; 211 } 212 /* 213 * get privkey 214 */ 215 fscanf(fp, "%x;", &len); 216 for (i=0;i<len;i++) { 217 j = getc(fp); key[i]=j; 218 } 219 fclose(fp); 220 221 r = accept_rsa_encpwd(&auth, key, challenge, 222 challenge_len, r_passwd); 223 if (r < 0) { 224 Data(ap, RSA_ENCPWD_REJECT, (void *)"Auth failed", -1); 225 auth_finished(ap, AUTH_REJECT); 226 return; 227 } 228 auth_encrypt_userpwd(r_passwd); 229 if (rsaencpwd_passwdok(UserNameRequested, UserPassword) == 0) { 230 /* 231 * illegal username and password 232 */ 233 Data(ap, RSA_ENCPWD_REJECT, (void *)"Illegal password", -1); 234 auth_finished(ap, AUTH_REJECT); 235 return; 236 } 237 238 Data(ap, RSA_ENCPWD_ACCEPT, (void *)0, 0); 239 auth_finished(ap, AUTH_USER); 240 break; 241 242 243 case IAC: 244 245 /* 246 * If we are doing mutual authentication, get set up to send 247 * the challenge, and verify it when the response comes back. 248 */ 249 if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_ONE_WAY) { 250 register int i; 251 252 253 time(&now); 254 if ((now % 2) == 0) { 255 sprintf(challenge, "%x", now); 256 challenge_len = strlen(challenge); 257 } else { 258 strcpy(challenge, "randchal"); 259 challenge_len = 8; 260 } 261 262 if ((fp=fopen(key_file, "r"))==NULL) { 263 Data(ap, RSA_ENCPWD_REJECT, (void *)"Auth failed", -1); 264 auth_finished(ap, AUTH_REJECT); 265 return; 266 } 267 /* 268 * skip privkey 269 */ 270 fscanf(fp, "%x;", &len); 271 for (i=0;i<len;i++) { 272 j = getc(fp); 273 } 274 /* 275 * get pubkey 276 */ 277 fscanf(fp, "%x;", &len); 278 for (i=0;i<len;i++) { 279 j = getc(fp); key[i]=j; 280 } 281 fclose(fp); 282 chalkey[0] = 0x30; 283 ptr = (char *) &chalkey[1]; 284 chalkey_len = 1+NumEncodeLengthOctets(i)+i+1+NumEncodeLengthOctets(challenge_len)+challenge_len; 285 EncodeLength(ptr, chalkey_len); 286 ptr +=NumEncodeLengthOctets(chalkey_len); 287 *ptr++ = 0x04; /* OCTET STRING */ 288 *ptr++ = challenge_len; 289 memmove(ptr, challenge, challenge_len); 290 ptr += challenge_len; 291 *ptr++ = 0x04; /* OCTET STRING */ 292 EncodeLength(ptr, i); 293 ptr += NumEncodeLengthOctets(i); 294 memmove(ptr, key, i); 295 chalkey_len = 1+NumEncodeLengthOctets(chalkey_len)+chalkey_len; 296 Data(ap, RSA_ENCPWD_CHALLENGEKEY, (void *)chalkey, chalkey_len); 297 } 298 break; 299 300 default: 301 Data(ap, RSA_ENCPWD_REJECT, 0, 0); 302 break; 303 } 304 } 305 306 307 void 308 rsaencpwd_reply(ap, data, cnt) 309 Authenticator *ap; 310 unsigned char *data; 311 int cnt; 312 { 313 Session_Key skey; 314 KTEXT_ST token; 315 Block enckey; 316 int r, pubkey_len; 317 char randchal[CHAL_SZ], *cp; 318 char chalkey[160], pubkey[128], *ptr; 319 320 if (cnt-- < 1) 321 return; 322 switch (*data++) { 323 case RSA_ENCPWD_REJECT: 324 if (cnt > 0) { 325 printf("[ RSA_ENCPWD refuses authentication because %.*s ]\r\n", 326 cnt, data); 327 } else 328 printf("[ RSA_ENCPWD refuses authentication ]\r\n"); 329 auth_send_retry(); 330 return; 331 case RSA_ENCPWD_ACCEPT: 332 printf("[ RSA_ENCPWD accepts you ]\n"); 333 auth_finished(ap, AUTH_USER); 334 return; 335 case RSA_ENCPWD_CHALLENGEKEY: 336 /* 337 * Verify that the response to the challenge is correct. 338 */ 339 340 memmove((void *)chalkey, (void *)data, cnt); 341 ptr = (char *) &chalkey[0]; 342 ptr += DecodeHeaderLength(chalkey); 343 if (*ptr != 0x04) { 344 return; 345 } 346 *ptr++; 347 challenge_len = DecodeValueLength(ptr); 348 ptr += NumEncodeLengthOctets(challenge_len); 349 memmove(challenge, ptr, challenge_len); 350 ptr += challenge_len; 351 if (*ptr != 0x04) { 352 return; 353 } 354 *ptr++; 355 pubkey_len = DecodeValueLength(ptr); 356 ptr += NumEncodeLengthOctets(pubkey_len); 357 memmove(pubkey, ptr, pubkey_len); 358 memset(user_passwd, 0, sizeof(user_passwd)); 359 local_des_read_pw_string(user_passwd, sizeof(user_passwd)-1, "Password: ", 0); 360 UserPassword = user_passwd; 361 Challenge = challenge; 362 r = init_rsa_encpwd(&token, user_passwd, challenge, challenge_len, pubkey); 363 if (r < 0) { 364 token.length = 1; 365 } 366 367 if (!Data(ap, RSA_ENCPWD_AUTH, (void *)token.dat, token.length)) { 368 return; 369 } 370 371 break; 372 373 default: 374 return; 375 } 376 } 377 378 int 379 rsaencpwd_status(ap, name, level) 380 Authenticator *ap; 381 char *name; 382 int level; 383 { 384 385 if (level < AUTH_USER) 386 return(level); 387 388 if (UserNameRequested && rsaencpwd_passwdok(UserNameRequested, UserPassword)) { 389 strcpy(name, UserNameRequested); 390 return(AUTH_VALID); 391 } else { 392 return(AUTH_USER); 393 } 394 } 395 396 #define BUMP(buf, len) while (*(buf)) {++(buf), --(len);} 397 #define ADDC(buf, len, c) if ((len) > 0) {*(buf)++ = (c); --(len);} 398 399 void 400 rsaencpwd_printsub(data, cnt, buf, buflen) 401 unsigned char *data, *buf; 402 int cnt, buflen; 403 { 404 char lbuf[32]; 405 register int i; 406 407 buf[buflen-1] = '\0'; /* make sure its NULL terminated */ 408 buflen -= 1; 409 410 switch(data[3]) { 411 case RSA_ENCPWD_REJECT: /* Rejected (reason might follow) */ 412 strncpy((char *)buf, " REJECT ", buflen); 413 goto common; 414 415 case RSA_ENCPWD_ACCEPT: /* Accepted (name might follow) */ 416 strncpy((char *)buf, " ACCEPT ", buflen); 417 common: 418 BUMP(buf, buflen); 419 if (cnt <= 4) 420 break; 421 ADDC(buf, buflen, '"'); 422 for (i = 4; i < cnt; i++) 423 ADDC(buf, buflen, data[i]); 424 ADDC(buf, buflen, '"'); 425 ADDC(buf, buflen, '\0'); 426 break; 427 428 case RSA_ENCPWD_AUTH: /* Authentication data follows */ 429 strncpy((char *)buf, " AUTH", buflen); 430 goto common2; 431 432 case RSA_ENCPWD_CHALLENGEKEY: 433 strncpy((char *)buf, " CHALLENGEKEY", buflen); 434 goto common2; 435 436 default: 437 sprintf(lbuf, " %d (unknown)", data[3]); 438 strncpy((char *)buf, lbuf, buflen); 439 common2: 440 BUMP(buf, buflen); 441 for (i = 4; i < cnt; i++) { 442 sprintf(lbuf, " %d", data[i]); 443 strncpy((char *)buf, lbuf, buflen); 444 BUMP(buf, buflen); 445 } 446 break; 447 } 448 } 449 450 int rsaencpwd_passwdok(name, passwd) 451 char *name, *passwd; 452 { 453 char *crypt(); 454 char *salt, *p; 455 struct passwd *pwd; 456 int passwdok_status = 0; 457 458 if (pwd = getpwnam(name)) 459 salt = pwd->pw_passwd; 460 else salt = "xx"; 461 462 p = crypt(passwd, salt); 463 464 if (pwd && !strcmp(p, pwd->pw_passwd)) { 465 passwdok_status = 1; 466 } else passwdok_status = 0; 467 return(passwdok_status); 468 } 469 470 #endif 471