sunrpc/auth_des.c

   1 #if defined(LIBC_SCCS) && !defined(lint)
   2 static char sccsid[] = "@(#)auth_des.c  2.2 88/07/29 4.0 RPCSRC; from 1.9 88/02/08 SMI";
   3 #endif
   4 /*
   5  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
   6  * unrestricted use provided that this legend is included on all tape
   7  * media and as a part of the software program in whole or part.  Users
   8  * may copy or modify Sun RPC without charge, but are not authorized
   9  * to license or distribute it to anyone else except as part of a product or
  10  * program developed by the user.
  11  *
  12  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  13  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  14  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  15  *
  16  * Sun RPC is provided with no support and without any obligation on the
  17  * part of Sun Microsystems, Inc. to assist in its use, correction,
  18  * modification or enhancement.
  19  *
  20  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  21  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  22  * OR ANY PART THEREOF.
  23  *
  24  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  25  * or profits or other special, indirect and consequential damages, even if
  26  * Sun has been advised of the possibility of such damages.
  27  *
  28  * Sun Microsystems, Inc.
  29  * 2550 Garcia Avenue
  30  * Mountain View, California  94043
  31  */
  32 /*
  33  * Copyright (c) 1988 by Sun Microsystems, Inc.
  34  */
  35 /*
  36  * auth_des.c, client-side implementation of DES authentication
  37  */
  38
  39 #include <string.h>
  40 #include <rpc/des_crypt.h>
  41 #include <rpc/types.h>
  42 #include <rpc/auth.h>
  43 #include <rpc/auth_des.h>
  44 #include <rpc/xdr.h>
  45 #include <netinet/in.h>         /* XXX: just to get htonl() and ntohl() */
  46 #include <sys/socket.h>
  47
  48 #define MILLION         1000000L
  49 #define RTIME_TIMEOUT 5         /* seconds to wait for sync */
  50
  51 #define AUTH_PRIVATE(auth)      (struct ad_private *) auth->ah_private
  52 #define ALLOC(object_type)      (object_type *) mem_alloc(sizeof(object_type))
  53 #define FREE(ptr, size)         mem_free((char *)(ptr), (int) size)
  54 #define ATTEMPT(xdr_op)         if (!(xdr_op)) return (FALSE)
  55
  56 #define debug(msg)              /* printf("%s\n", msg) */
  57
  58 extern int rtime (struct sockaddr_in *, struct timeval *, struct timeval *);
  59 extern bool_t xdr_authdes_cred (XDR *, struct authdes_cred *);
  60 extern bool_t xdr_authdes_verf (XDR *, struct authdes_verf *);
  61
  62 /*
  63  * DES authenticator operations vector
  64  */
  65 AUTH *authdes_create (const char *, u_int, struct sockaddr *,
  66                       des_block *);
  67 AUTH *authdes_pk_create (const char *, netobj *, u_int,
  68                          struct sockaddr *, des_block *);
  69 static void authdes_nextverf (AUTH *);
  70 static bool_t authdes_marshal (AUTH *, XDR *);
  71 static bool_t authdes_validate (AUTH *, struct opaque_auth *);
  72 static bool_t authdes_refresh (AUTH *);
  73 static void authdes_destroy (AUTH *);
  74 static bool_t synchronize (struct sockaddr *, struct timeval *)
  75      internal_function;
  76
  77 static struct auth_ops authdes_ops =
  78 {
  79   authdes_nextverf,
  80   authdes_marshal,
  81   authdes_validate,
  82   authdes_refresh,
  83   authdes_destroy
  84 };
  85
  86
  87 /*
  88  * This struct is pointed to by the ah_private field of an "AUTH *"
  89  */
  90 struct ad_private
  91   {
  92     char *ad_fullname;          /* client's full name */
  93     u_int ad_fullnamelen;       /* length of name, rounded up */
  94     char *ad_servername;        /* server's full name */
  95     u_int ad_servernamelen;     /* length of name, rounded up */
  96     u_int ad_window;            /* client specified window */
  97     bool_t ad_dosync;           /* synchronize? */
  98     struct sockaddr ad_syncaddr;        /* remote host to synch with */
  99     struct timeval ad_timediff; /* server's time - client's time */
 100     u_long ad_nickname;         /* server's nickname for client */
 101     struct authdes_cred ad_cred;        /* storage for credential */
 102     struct authdes_verf ad_verf;        /* storage for verifier */
 103     struct timeval ad_timestamp;        /* timestamp sent */
 104     des_block ad_xkey;          /* encrypted conversation key */
 105     u_char ad_pkey[1024];       /* Servers actual public key */
 106   };
 107
 108
 109 /*
 110  * Create the client des authentication object
 111  */
 112 AUTH *
 113 authdes_create (const char *servername, u_int window,
 114                 struct sockaddr *syncaddr, des_block * ckey)
 115   /* servername - network name of server */
 116   /* window     - time to live */
 117   /* syncaddr   - optional addr of host to sync with */
 118   /* ckey       - optional conversation key to use */
 119 {
 120   u_char pkey_data[1024];
 121   netobj pkey;
 122
 123   if (!getpublickey (servername, pkey_data))
 124     return (NULL);
 125
 126   pkey.n_bytes = (char *) pkey_data;
 127   pkey.n_len = strlen ((char *) pkey_data) + 1;
 128   return authdes_pk_create (servername, &pkey, window, syncaddr, ckey);
 129 }
 130
 131 AUTH *
 132 authdes_pk_create (const char *servername, netobj * pkey, u_int window,
 133                    struct sockaddr * syncaddr, des_block * ckey)
 134 {
 135   AUTH *auth;
 136   struct ad_private *ad;
 137   char namebuf[MAXNETNAMELEN + 1];
 138
 139   /*
 140    * Allocate everything now
 141    */
 142   auth = ALLOC (AUTH);
 143   ad = ALLOC (struct ad_private);
 144   memset (ad, 0, sizeof (struct ad_private));
 145   memcpy (ad->ad_pkey, pkey->n_bytes, pkey->n_len);
 146   if (!getnetname (namebuf))
 147     goto failed;
 148   ad->ad_fullnamelen = RNDUP (strlen (namebuf));
 149   ad->ad_fullname = mem_alloc (ad->ad_fullnamelen + 1);
 150
 151   ad->ad_servernamelen = strlen (servername);
 152   ad->ad_servername = mem_alloc (ad->ad_servernamelen + 1);
 153
 154   if (auth == NULL || ad == NULL || ad->ad_fullname == NULL ||
 155       ad->ad_servername == NULL)
 156     {
 157       debug ("authdes_create: out of memory");
 158       goto failed;
 159     }
 160
 161   /*
 162    * Set up private data
 163    */
 164   bcopy (namebuf, ad->ad_fullname, ad->ad_fullnamelen + 1);
 165   bcopy (servername, ad->ad_servername, ad->ad_servernamelen + 1);
 166   ad->ad_timediff.tv_sec = ad->ad_timediff.tv_usec = 0;
 167   if (syncaddr != NULL)
 168     {
 169       ad->ad_syncaddr = *syncaddr;
 170       ad->ad_dosync = TRUE;
 171     }
 172   else
 173     ad->ad_dosync = FALSE;
 174
 175   ad->ad_window = window;
 176   if (ckey == NULL)
 177     {
 178       if (key_gendes (&auth->ah_key) < 0)
 179         {
 180           debug ("authdes_create: unable to gen conversation key");
 181           return (NULL);
 182         }
 183     }
 184   else
 185     auth->ah_key = *ckey;
 186
 187   /*
 188    * Set up auth handle
 189    */
 190   auth->ah_cred.oa_flavor = AUTH_DES;
 191   auth->ah_verf.oa_flavor = AUTH_DES;
 192   auth->ah_ops = &authdes_ops;
 193   auth->ah_private = (caddr_t) ad;
 194
 195   if (!authdes_refresh (auth))
 196     goto failed;
 197
 198   return (auth);
 199
 200 failed:
 201   if (auth != NULL)
 202     FREE (auth, sizeof (AUTH));
 203   if (ad != NULL)
 204     {
 205       if (ad->ad_fullname != NULL)
 206         FREE (ad->ad_fullname, ad->ad_fullnamelen + 1);
 207       if (ad->ad_servername != NULL)
 208         FREE (ad->ad_servername, ad->ad_servernamelen + 1);
 209       FREE (ad, sizeof (struct ad_private));
 210     }
 211   return (NULL);
 212 }
 213
 214 /*
 215  * Implement the five authentication operations
 216  */
 217
 218
 219 /*
 220  * 1. Next Verifier
 221  */
 222 /*ARGSUSED */
 223 static void
 224 authdes_nextverf (AUTH * auth)
 225 {
 226   /* what the heck am I supposed to do??? */
 227 }
 228
 229
 230
 231 /*
 232  * 2. Marshal
 233  */
 234 static bool_t
 235 authdes_marshal (AUTH * auth, XDR * xdrs)
 236 {
 237   struct ad_private *ad = AUTH_PRIVATE (auth);
 238   struct authdes_cred *cred = &ad->ad_cred;
 239   struct authdes_verf *verf = &ad->ad_verf;
 240   des_block cryptbuf[2];
 241   des_block ivec;
 242   int status;
 243   int len;
 244   register long *ixdr;
 245
 246   /*
 247    * Figure out the "time", accounting for any time difference
 248    * with the server if necessary.
 249    */
 250   gettimeofday (&ad->ad_timestamp, (struct timezone *) NULL);
 251   ad->ad_timestamp.tv_sec += ad->ad_timediff.tv_sec;
 252   ad->ad_timestamp.tv_usec += ad->ad_timediff.tv_usec;
 253   if (ad->ad_timestamp.tv_usec >= MILLION)
 254     {
 255       ad->ad_timestamp.tv_usec -= MILLION;
 256       ad->ad_timestamp.tv_sec += 1;
 257     }
 258
 259   /*
 260    * XDR the timestamp and possibly some other things, then
 261    * encrypt them.
 262    */
 263   ixdr = (long *) cryptbuf;
 264   IXDR_PUT_LONG (ixdr, ad->ad_timestamp.tv_sec);
 265   IXDR_PUT_LONG (ixdr, ad->ad_timestamp.tv_usec);
 266   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 267     {
 268       IXDR_PUT_U_LONG (ixdr, ad->ad_window);
 269       IXDR_PUT_U_LONG (ixdr, ad->ad_window - 1);
 270       ivec.key.high = ivec.key.low = 0;
 271       status = cbc_crypt ((char *) &auth->ah_key, (char *) cryptbuf,
 272               2 * sizeof (des_block), DES_ENCRYPT | DES_HW, (char *) &ivec);
 273     }
 274   else
 275     {
 276       status = ecb_crypt ((char *) &auth->ah_key, (char *) cryptbuf,
 277                           sizeof (des_block), DES_ENCRYPT | DES_HW);
 278     }
 279   if (DES_FAILED (status))
 280     {
 281       debug ("authdes_marshal: DES encryption failure");
 282       return (FALSE);
 283     }
 284   ad->ad_verf.adv_xtimestamp = cryptbuf[0];
 285   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 286     {
 287       ad->ad_cred.adc_fullname.window = cryptbuf[1].key.high;
 288       ad->ad_verf.adv_winverf = cryptbuf[1].key.low;
 289     }
 290   else
 291     {
 292       ad->ad_cred.adc_nickname = ad->ad_nickname;
 293       ad->ad_verf.adv_winverf = 0;
 294     }
 295
 296   /*
 297    * Serialize the credential and verifier into opaque
 298    * authentication data.
 299    */
 300   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 301     {
 302       len = ((1 + 1 + 2 + 1) * BYTES_PER_XDR_UNIT + ad->ad_fullnamelen);
 303     }
 304   else
 305     {
 306       len = (1 + 1) * BYTES_PER_XDR_UNIT;
 307     }
 308
 309   if ((ixdr = xdr_inline (xdrs, 2 * BYTES_PER_XDR_UNIT)) != NULL)
 310     {
 311       IXDR_PUT_LONG (ixdr, AUTH_DES);
 312       IXDR_PUT_LONG (ixdr, len);
 313     }
 314   else
 315     {
 316       ATTEMPT (xdr_putlong (xdrs, (long *)&auth->ah_cred.oa_flavor));
 317       ATTEMPT (xdr_putlong (xdrs, (long *)&len));
 318     }
 319   ATTEMPT (xdr_authdes_cred (xdrs, cred));
 320
 321   len = (2 + 1) * BYTES_PER_XDR_UNIT;
 322   if ((ixdr = xdr_inline (xdrs, 2 * BYTES_PER_XDR_UNIT)) != NULL)
 323     {
 324       IXDR_PUT_LONG (ixdr, AUTH_DES);
 325       IXDR_PUT_LONG (ixdr, len);
 326     }
 327   else
 328     {
 329       ATTEMPT (xdr_putlong (xdrs, (long *)&auth->ah_verf.oa_flavor));
 330       ATTEMPT (xdr_putlong (xdrs, (long *)&len));
 331     }
 332   ATTEMPT (xdr_authdes_verf (xdrs, verf));
 333   return (TRUE);
 334 }
 335
 336
 337 /*
 338  * 3. Validate
 339  */
 340 static bool_t
 341 authdes_validate (AUTH * auth, struct opaque_auth *rverf)
 342 {
 343   struct ad_private *ad = AUTH_PRIVATE (auth);
 344   struct authdes_verf verf;
 345   int status;
 346   register u_long *ixdr;
 347
 348   if (rverf->oa_length != (2 + 1) * BYTES_PER_XDR_UNIT)
 349     return (FALSE);
 350
 351   ixdr = (u_long *) rverf->oa_base;
 352   verf.adv_xtimestamp.key.high = (u_long) * ixdr++;
 353   verf.adv_xtimestamp.key.low = (u_long) * ixdr++;
 354   verf.adv_int_u = (u_long) * ixdr++;   /* nickname not XDR'd ! */
 355
 356   /*
 357    * Decrypt the timestamp
 358    */
 359   status = ecb_crypt ((char *) &auth->ah_key, (char *) &verf.adv_xtimestamp,
 360                       sizeof (des_block), DES_DECRYPT | DES_HW);
 361
 362   if (DES_FAILED (status))
 363     {
 364       debug ("authdes_validate: DES decryption failure");
 365       return (FALSE);
 366     }
 367
 368   /*
 369    * xdr the decrypted timestamp
 370    */
 371   ixdr = (u_long *) verf.adv_xtimestamp.c;
 372   verf.adv_timestamp.tv_sec = IXDR_GET_LONG (ixdr) + 1;
 373   verf.adv_timestamp.tv_usec = IXDR_GET_LONG (ixdr);
 374
 375   /*
 376    * validate
 377    */
 378   if (bcmp ((char *) &ad->ad_timestamp, (char *) &verf.adv_timestamp,
 379             sizeof (struct timeval)) != 0)
 380     {
 381       debug ("authdes_validate: verifier mismatch\n");
 382       return (FALSE);
 383     }
 384
 385   /*
 386    * We have a nickname now, let's use it
 387    */
 388   ad->ad_nickname = verf.adv_nickname;
 389   ad->ad_cred.adc_namekind = ADN_NICKNAME;
 390   return (TRUE);
 391 }
 392
 393 /*
 394  * 4. Refresh
 395  */
 396 static bool_t
 397 authdes_refresh (AUTH * auth)
 398 {
 399   netobj pkey;
 400   struct ad_private *ad = AUTH_PRIVATE (auth);
 401   struct authdes_cred *cred = &ad->ad_cred;
 402
 403   if (ad->ad_dosync &&
 404       !synchronize (&ad->ad_syncaddr, &ad->ad_timediff))
 405     {
 406       /*
 407        * Hope the clocks are synced!
 408        */
 409       ad->ad_timediff.tv_sec = ad->ad_timediff.tv_usec = 0;
 410       debug ("authdes_refresh: unable to synchronize with server");
 411     }
 412   ad->ad_xkey = auth->ah_key;
 413   pkey.n_bytes = (char *) (ad->ad_pkey);
 414   pkey.n_len = strlen ((char *) ad->ad_pkey) + 1;
 415   if (key_encryptsession_pk (ad->ad_servername, &pkey, &ad->ad_xkey) < 0)
 416     {
 417       debug ("authdes_create: unable to encrypt conversation key");
 418       return (FALSE);
 419     }
 420   cred->adc_fullname.key = ad->ad_xkey;
 421   cred->adc_namekind = ADN_FULLNAME;
 422   cred->adc_fullname.name = ad->ad_fullname;
 423   return (TRUE);
 424 }
 425
 426 /*
 427  * 5. Destroy
 428  */
 429 static void
 430 authdes_destroy (AUTH * auth)
 431 {
 432   struct ad_private *ad = AUTH_PRIVATE (auth);
 433
 434   FREE (ad->ad_fullname, ad->ad_fullnamelen + 1);
 435   FREE (ad->ad_servername, ad->ad_servernamelen + 1);
 436   FREE (ad, sizeof (struct ad_private));
 437   FREE (auth, sizeof (AUTH));
 438 }
 439
 440 /*
 441  * Synchronize with the server at the given address, that is,
 442  * adjust timep to reflect the delta between our clocks
 443  */
 444 static bool_t
 445 internal_function
 446 synchronize (struct sockaddr *syncaddr, struct timeval *timep)
 447 {
 448   struct timeval mytime;
 449   struct timeval timeout;
 450
 451   timeout.tv_sec = RTIME_TIMEOUT;
 452   timeout.tv_usec = 0;
 453   if (rtime ((struct sockaddr_in *) syncaddr, timep, &timeout) < 0)
 454     return (FALSE);
 455
 456   gettimeofday (&mytime, (struct timezone *) NULL);
 457   timep->tv_sec -= mytime.tv_sec;
 458   if (mytime.tv_usec > timep->tv_usec)
 459     {
 460       timep->tv_sec -= 1;
 461       timep->tv_usec += MILLION;
 462     }
 463   timep->tv_usec -= mytime.tv_usec;
 464   return (TRUE);
 465 }