crypto/dist/heimdal/appl/telnet/libtelnet/rsaencpwd.c

   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 <config.h>
  35
  36 __RCSID("$Heimdal: rsaencpwd.c 22071 2007-11-14 20:04:50Z lha $"
  37         "$NetBSD$");
  38
  39 #ifdef  RSA_ENCPWD
  40 /*
  41  * COPYRIGHT (C) 1990 DIGITAL EQUIPMENT CORPORATION
  42  * ALL RIGHTS RESERVED
  43  *
  44  * "Digital Equipment Corporation authorizes the reproduction,
  45  * distribution and modification of this software subject to the following
  46  * restrictions:
  47  *
  48  * 1.  Any partial or whole copy of this software, or any modification
  49  * thereof, must include this copyright notice in its entirety.
  50  *
  51  * 2.  This software is supplied "as is" with no warranty of any kind,
  52  * expressed or implied, for any purpose, including any warranty of fitness
  53  * or merchantibility.  DIGITAL assumes no responsibility for the use or
  54  * reliability of this software, nor promises to provide any form of
  55  * support for it on any basis.
  56  *
  57  * 3.  Distribution of this software is authorized only if no profit or
  58  * remuneration of any kind is received in exchange for such distribution.
  59  *
  60  * 4.  This software produces public key authentication certificates
  61  * bearing an expiration date established by DIGITAL and RSA Data
  62  * Security, Inc.  It may cease to generate certificates after the expiration
  63  * date.  Any modification of this software that changes or defeats
  64  * the expiration date or its effect is unauthorized.
  65  *
  66  * 5.  Software that will renew or extend the expiration date of
  67  * authentication certificates produced by this software may be obtained
  68  * from RSA Data Security, Inc., 10 Twin Dolphin Drive, Redwood City, CA
  69  * 94065, (415)595-8782, or from DIGITAL"
  70  *
  71  */
  72
  73 #include <sys/types.h>
  74 #ifdef HAVE_ARPA_TELNET_H
  75 #include <arpa/telnet.h>
  76 #endif
  77 #include <pwd.h>
  78 #include <stdio.h>
  79
  80 #include <stdlib.h>
  81 #include <string.h>
  82 #ifdef SOCKS
  83 #include <socks.h>
  84 #endif
  85
  86 #include "encrypt.h"
  87 #include "auth.h"
  88 #include "misc.h"
  89 #include "cdc.h"
  90
  91 extern auth_debug_mode;
  92
  93 static unsigned char str_data[1024] = { IAC, SB, TELOPT_AUTHENTICATION, 0,
  94                                         AUTHTYPE_RSA_ENCPWD, };
  95 static unsigned char str_name[1024] = { IAC, SB, TELOPT_AUTHENTICATION,
  96                                         TELQUAL_NAME, };
  97
  98 #define RSA_ENCPWD_AUTH 0       /* Authentication data follows */
  99 #define RSA_ENCPWD_REJECT       1       /* Rejected (reason might follow) */
 100 #define RSA_ENCPWD_ACCEPT       2       /* Accepted */
 101 #define RSA_ENCPWD_CHALLENGEKEY 3       /* Challenge and public key */
 102
 103 #define NAME_SZ   40
 104 #define CHAL_SZ   20
 105 #define PWD_SZ    40
 106
 107 static  KTEXT_ST auth;
 108 static  char name[NAME_SZ];
 109 static  char user_passwd[PWD_SZ];
 110 static  char key_file[2*NAME_SZ];
 111 static  char lhostname[NAME_SZ];
 112 static char  challenge[CHAL_SZ];
 113 static int   challenge_len;
 114
 115         static int
 116 Data(ap, type, d, c)
 117         Authenticator *ap;
 118         int type;
 119         void *d;
 120         int c;
 121 {
 122         unsigned char *p = str_data + 4;
 123         unsigned char *cd = (unsigned char *)d;
 124
 125         if (c == -1)
 126                 c = strlen((char *)cd);
 127
 128         if (0) {
 129                 printf("%s:%d: [%d] (%d)",
 130                         str_data[3] == TELQUAL_IS ? ">>>IS" : ">>>REPLY",
 131                         str_data[3],
 132                         type, c);
 133                 printd(d, c);
 134                 printf("\r\n");
 135         }
 136         *p++ = ap->type;
 137         *p++ = ap->way;
 138         if (type != NULL) *p++ = type;
 139         while (c-- > 0) {
 140                 if ((*p++ = *cd++) == IAC)
 141                         *p++ = IAC;
 142         }
 143         *p++ = IAC;
 144         *p++ = SE;
 145         if (str_data[3] == TELQUAL_IS)
 146                 printsub('>', &str_data[2], p - (&str_data[2]));
 147         return(telnet_net_write(str_data, p - str_data));
 148 }
 149
 150         int
 151 rsaencpwd_init(ap, server)
 152         Authenticator *ap;
 153         int server;
 154 {
 155         char  *cp;
 156         FILE  *fp;
 157
 158         if (server) {
 159                 str_data[3] = TELQUAL_REPLY;
 160                 memset(key_file, 0, sizeof(key_file));
 161                 gethostname(lhostname, sizeof(lhostname));
 162                 if ((cp = strchr(lhostname, '.')) != 0)  *cp = '\0';
 163                 snprintf(key_file, sizeof(key_file),
 164                          SYSCONFDIR "/.%s_privkey", lhostname);
 165                 if ((fp=fopen(key_file, "r"))==NULL) return(0);
 166                 fclose(fp);
 167         } else {
 168                 str_data[3] = TELQUAL_IS;
 169         }
 170         return(1);
 171 }
 172
 173         int
 174 rsaencpwd_send(ap)
 175         Authenticator *ap;
 176 {
 177
 178         printf("[ Trying RSAENCPWD ... ]\r\n");
 179         if (!UserNameRequested) {
 180                 return(0);
 181         }
 182         if (!auth_sendname(UserNameRequested, strlen(UserNameRequested))) {
 183                 return(0);
 184         }
 185         if (!Data(ap, NULL, NULL, 0)) {
 186                 return(0);
 187         }
 188
 189
 190         return(1);
 191 }
 192
 193         void
 194 rsaencpwd_is(ap, data, cnt)
 195         Authenticator *ap;
 196         unsigned char *data;
 197         int cnt;
 198 {
 199         Session_Key skey;
 200         des_cblock datablock;
 201         char  r_passwd[PWD_SZ], r_user[NAME_SZ];
 202         char  *cp, key[160];
 203         char  chalkey[160], *ptr;
 204         FILE  *fp;
 205         int r, i, j, chalkey_len, len;
 206         time_t now;
 207
 208         cnt--;
 209         switch (*data++) {
 210         case RSA_ENCPWD_AUTH:
 211                 memmove(auth.dat, data, auth.length = cnt);
 212
 213                 if ((fp=fopen(key_file, "r"))==NULL) {
 214                   Data(ap, RSA_ENCPWD_REJECT, "Auth failed", -1);
 215                   auth_finished(ap, AUTH_REJECT);
 216                   return;
 217                 }
 218                 /*
 219                  *  get privkey
 220                  */
 221                 fscanf(fp, "%x;", &len);
 222                 for (i=0;i<len;i++) {
 223                   j = getc(fp);  key[i]=j;
 224                 }
 225                 fclose(fp);
 226
 227                 r = accept_rsa_encpwd(&auth, key, challenge,
 228                                       challenge_len, r_passwd);
 229                 if (r < 0) {
 230                   Data(ap, RSA_ENCPWD_REJECT, "Auth failed", -1);
 231                   auth_finished(ap, AUTH_REJECT);
 232                   return;
 233                 }
 234                 auth_encrypt_userpwd(r_passwd);
 235                 if (rsaencpwd_passwdok(UserNameRequested, UserPassword) == 0) {
 236                   /*
 237                    *  illegal username and password
 238                    */
 239                   Data(ap, RSA_ENCPWD_REJECT, "Illegal password", -1);
 240                   auth_finished(ap, AUTH_REJECT);
 241                   return;
 242                 }
 243
 244                 Data(ap, RSA_ENCPWD_ACCEPT, 0, 0);
 245                 auth_finished(ap, AUTH_USER);
 246                 break;
 247
 248
 249         case IAC:
 250
 251                 /*
 252                  * If we are doing mutual authentication, get set up to send
 253                  * the challenge, and verify it when the response comes back.
 254                  */
 255                 if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_ONE_WAY) {
 256                   int i;
 257
 258
 259                   time(&now);
 260                   if ((now % 2) == 0) {
 261                     snprintf(challenge, sizeof(challenge), "%x", now);
 262                     challenge_len = strlen(challenge);
 263                   } else {
 264                     strlcpy(challenge, "randchal", sizeof(challenge));
 265                     challenge_len = 8;
 266                   }
 267
 268                   if ((fp=fopen(key_file, "r"))==NULL) {
 269                     Data(ap, RSA_ENCPWD_REJECT, "Auth failed", -1);
 270                     auth_finished(ap, AUTH_REJECT);
 271                     return;
 272                   }
 273                   /*
 274                    *  skip privkey
 275                    */
 276                   fscanf(fp, "%x;", &len);
 277                   for (i=0;i<len;i++) {
 278                     j = getc(fp);
 279                   }
 280                   /*
 281                    * get pubkey
 282                    */
 283                   fscanf(fp, "%x;", &len);
 284                   for (i=0;i<len;i++) {
 285                     j = getc(fp);  key[i]=j;
 286                   }
 287                   fclose(fp);
 288                   chalkey[0] = 0x30;
 289                   ptr = (char *) &chalkey[1];
 290                   chalkey_len = 1+NumEncodeLengthOctets(i)+i+1+NumEncodeLengthOctets(challenge_len)+challenge_len;
 291                   EncodeLength(ptr, chalkey_len);
 292                   ptr +=NumEncodeLengthOctets(chalkey_len);
 293                   *ptr++ = 0x04;  /* OCTET STRING */
 294                   *ptr++ = challenge_len;
 295                   memmove(ptr, challenge, challenge_len);
 296                   ptr += challenge_len;
 297                   *ptr++ = 0x04;  /* OCTET STRING */
 298                   EncodeLength(ptr, i);
 299                   ptr += NumEncodeLengthOctets(i);
 300                   memmove(ptr, key, i);
 301                   chalkey_len = 1+NumEncodeLengthOctets(chalkey_len)+chalkey_len;
 302                   Data(ap, RSA_ENCPWD_CHALLENGEKEY, chalkey, chalkey_len);
 303                 }
 304                 break;
 305
 306         default:
 307                 Data(ap, RSA_ENCPWD_REJECT, 0, 0);
 308                 break;
 309         }
 310 }
 311
 312
 313         void
 314 rsaencpwd_reply(ap, data, cnt)
 315         Authenticator *ap;
 316         unsigned char *data;
 317         int cnt;
 318 {
 319         Session_Key skey;
 320         KTEXT_ST token;
 321         des_cblock enckey;
 322         int r, pubkey_len;
 323         char    randchal[CHAL_SZ], *cp;
 324         char    chalkey[160], pubkey[128], *ptr;
 325
 326         if (cnt-- < 1)
 327                 return;
 328         switch (*data++) {
 329         case RSA_ENCPWD_REJECT:
 330                 if (cnt > 0) {
 331                         printf("[ RSA_ENCPWD refuses authentication because %.*s ]\r\n",
 332                                 cnt, data);
 333                 } else
 334                         printf("[ RSA_ENCPWD refuses authentication ]\r\n");
 335                 auth_send_retry();
 336                 return;
 337         case RSA_ENCPWD_ACCEPT:
 338                 printf("[ RSA_ENCPWD accepts you ]\r\n");
 339                 auth_finished(ap, AUTH_USER);
 340                 return;
 341         case RSA_ENCPWD_CHALLENGEKEY:
 342                 /*
 343                  * Verify that the response to the challenge is correct.
 344                  */
 345
 346                 memmove(chalkey, data, cnt);
 347                 ptr = (char *) &chalkey[0];
 348                 ptr += DecodeHeaderLength(chalkey);
 349                 if (*ptr != 0x04) {
 350                   return;
 351                 }
 352                 *ptr++;
 353                 challenge_len = DecodeValueLength(ptr);
 354                 ptr += NumEncodeLengthOctets(challenge_len);
 355                 memmove(challenge, ptr, challenge_len);
 356                 ptr += challenge_len;
 357                 if (*ptr != 0x04) {
 358                   return;
 359                 }
 360                 *ptr++;
 361                 pubkey_len = DecodeValueLength(ptr);
 362                 ptr += NumEncodeLengthOctets(pubkey_len);
 363                 memmove(pubkey, ptr, pubkey_len);
 364                 memset(user_passwd, 0, sizeof(user_passwd));
 365                 des_read_pw_string(user_passwd, sizeof(user_passwd)-1, "Password: ", 0);
 366                 UserPassword = user_passwd;
 367                 Challenge = challenge;
 368                 r = init_rsa_encpwd(&token, user_passwd, challenge, challenge_len, pubkey);
 369                 if (r < 0) {
 370                   token.length = 1;
 371                 }
 372
 373                 if (!Data(ap, RSA_ENCPWD_AUTH, token.dat, token.length)) {
 374                   return;
 375                 }
 376
 377                 break;
 378
 379         default:
 380                 return;
 381         }
 382 }
 383
 384         int
 385 rsaencpwd_status(ap, name, name_sz, level)
 386         Authenticator *ap;
 387         char *name;
 388         size_t name_sz;
 389         int level;
 390 {
 391
 392         if (level < AUTH_USER)
 393                 return(level);
 394
 395         if (UserNameRequested && rsaencpwd_passwdok(UserNameRequested, UserPassword)) {
 396                 strlcpy(name, UserNameRequested, name_sz);
 397                 return(AUTH_VALID);
 398         } else {
 399                 return(AUTH_USER);
 400         }
 401 }
 402
 403 #define BUMP(buf, len)          while (*(buf)) {++(buf), --(len);}
 404 #define ADDC(buf, len, c)       if ((len) > 0) {*(buf)++ = (c); --(len);}
 405
 406         void
 407 rsaencpwd_printsub(data, cnt, buf, buflen)
 408         unsigned char *data, *buf;
 409         int cnt, buflen;
 410 {
 411         int i;
 412
 413         buf[buflen-1] = '\0';           /* make sure it's NULL terminated */
 414         buflen -= 1;
 415
 416         switch(data[3]) {
 417         case RSA_ENCPWD_REJECT: /* Rejected (reason might follow) */
 418                 strlcpy((char *)buf, " REJECT ", buflen);
 419                 goto common;
 420
 421         case RSA_ENCPWD_ACCEPT: /* Accepted (name might follow) */
 422                 strlcpy((char *)buf, " ACCEPT ", buflen);
 423         common:
 424                 BUMP(buf, buflen);
 425                 if (cnt <= 4)
 426                         break;
 427                 ADDC(buf, buflen, '"');
 428                 for (i = 4; i < cnt; i++)
 429                         ADDC(buf, buflen, data[i]);
 430                 ADDC(buf, buflen, '"');
 431                 ADDC(buf, buflen, '\0');
 432                 break;
 433
 434         case RSA_ENCPWD_AUTH:           /* Authentication data follows */
 435                 strlcpy((char *)buf, " AUTH", buflen);
 436                 goto common2;
 437
 438         case RSA_ENCPWD_CHALLENGEKEY:
 439                 strlcpy((char *)buf, " CHALLENGEKEY", buflen);
 440                 goto common2;
 441
 442         default:
 443                 snprintf(buf, buflen, " %d (unknown)", data[3]);
 444         common2:
 445                 BUMP(buf, buflen);
 446                 for (i = 4; i < cnt; i++) {
 447                         snprintf(buf, buflen, " %d", data[i]);
 448                         BUMP(buf, buflen);
 449                 }
 450                 break;
 451         }
 452 }
 453
 454 int rsaencpwd_passwdok(name, passwd)
 455 char *name, *passwd;
 456 {
 457   char *crypt();
 458   char *salt, *p;
 459   struct passwd *pwd;
 460   int   passwdok_status = 0;
 461
 462   if (pwd = k_getpwnam(name))
 463     salt = pwd->pw_passwd;
 464   else salt = "xx";
 465
 466   p = crypt(passwd, salt);
 467
 468   if (pwd && !strcmp(p, pwd->pw_passwd)) {
 469     passwdok_status = 1;
 470   } else passwdok_status = 0;
 471   return(passwdok_status);
 472 }
 473
 474 #endif
 475
 476 #ifdef notdef
 477
 478 prkey(msg, key)
 479         char *msg;
 480         unsigned char *key;
 481 {
 482         int i;
 483         printf("%s:", msg);
 484         for (i = 0; i < 8; i++)
 485                 printf(" %3d", key[i]);
 486         printf("\r\n");
 487 }
 488 #endif