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 static void authdes_nextverf (AUTH *);
  66 static bool_t authdes_marshal (AUTH *, XDR *);
  67 static bool_t authdes_validate (AUTH *, struct opaque_auth *);
  68 static bool_t authdes_refresh (AUTH *);
  69 static void authdes_destroy (AUTH *);
  70 static bool_t synchronize (struct sockaddr *, struct timeval *)
  71      internal_function;
  72
  73 static struct auth_ops authdes_ops =
  74 {
  75   authdes_nextverf,
  76   authdes_marshal,
  77   authdes_validate,
  78   authdes_refresh,
  79   authdes_destroy
  80 };
  81
  82
  83 /*
  84  * This struct is pointed to by the ah_private field of an "AUTH *"
  85  */
  86 struct ad_private
  87   {
  88     char *ad_fullname;          /* client's full name */
  89     u_int ad_fullnamelen;       /* length of name, rounded up */
  90     char *ad_servername;        /* server's full name */
  91     u_int ad_servernamelen;     /* length of name, rounded up */
  92     u_int ad_window;            /* client specified window */
  93     bool_t ad_dosync;           /* synchronize? */
  94     struct sockaddr ad_syncaddr;        /* remote host to synch with */
  95     struct timeval ad_timediff; /* server's time - client's time */
  96     u_long ad_nickname;         /* server's nickname for client */
  97     struct authdes_cred ad_cred;        /* storage for credential */
  98     struct authdes_verf ad_verf;        /* storage for verifier */
  99     struct timeval ad_timestamp;        /* timestamp sent */
 100     des_block ad_xkey;          /* encrypted conversation key */
 101     u_char ad_pkey[1024];       /* Servers actual public key */
 102   };
 103
 104
 105 /*
 106  * Create the client des authentication object
 107  */
 108 AUTH *
 109 authdes_create (const char *servername, u_int window,
 110                 struct sockaddr *syncaddr, des_block *ckey)
 111   /* servername - network name of server */
 112   /* window     - time to live */
 113   /* syncaddr   - optional addr of host to sync with */
 114   /* ckey       - optional conversation key to use */
 115 {
 116   u_char pkey_data[1024];
 117   netobj pkey;
 118
 119   if (!getpublickey (servername, pkey_data))
 120     return (NULL);
 121
 122   pkey.n_bytes = (char *) pkey_data;
 123   pkey.n_len = strlen ((char *) pkey_data) + 1;
 124   return authdes_pk_create (servername, &pkey, window, syncaddr, ckey);
 125 }
 126
 127 AUTH *
 128 authdes_pk_create (const char *servername, netobj *pkey, u_int window,
 129                    struct sockaddr *syncaddr, des_block *ckey)
 130 {
 131   AUTH *auth;
 132   struct ad_private *ad;
 133   char namebuf[MAXNETNAMELEN + 1];
 134
 135   /*
 136    * Allocate everything now
 137    */
 138   auth = ALLOC (AUTH);
 139   ad = ALLOC (struct ad_private);
 140   memset (ad, 0, sizeof (struct ad_private));
 141   memcpy (ad->ad_pkey, pkey->n_bytes, pkey->n_len);
 142   if (!getnetname (namebuf))
 143     goto failed;
 144   ad->ad_fullnamelen = RNDUP (strlen (namebuf));
 145   ad->ad_fullname = mem_alloc (ad->ad_fullnamelen + 1);
 146
 147   ad->ad_servernamelen = strlen (servername);
 148   ad->ad_servername = mem_alloc (ad->ad_servernamelen + 1);
 149
 150   if (auth == NULL || ad == NULL || ad->ad_fullname == NULL ||
 151       ad->ad_servername == NULL)
 152     {
 153       debug ("authdes_create: out of memory");
 154       goto failed;
 155     }
 156
 157   /*
 158    * Set up private data
 159    */
 160   bcopy (namebuf, ad->ad_fullname, ad->ad_fullnamelen + 1);
 161   bcopy (servername, ad->ad_servername, ad->ad_servernamelen + 1);
 162   ad->ad_timediff.tv_sec = ad->ad_timediff.tv_usec = 0;
 163   if (syncaddr != NULL)
 164     {
 165       ad->ad_syncaddr = *syncaddr;
 166       ad->ad_dosync = TRUE;
 167     }
 168   else
 169     ad->ad_dosync = FALSE;
 170
 171   ad->ad_window = window;
 172   if (ckey == NULL)
 173     {
 174       if (key_gendes (&auth->ah_key) < 0)
 175         {
 176           debug ("authdes_create: unable to gen conversation key");
 177           return (NULL);
 178         }
 179     }
 180   else
 181     auth->ah_key = *ckey;
 182
 183   /*
 184    * Set up auth handle
 185    */
 186   auth->ah_cred.oa_flavor = AUTH_DES;
 187   auth->ah_verf.oa_flavor = AUTH_DES;
 188   auth->ah_ops = &authdes_ops;
 189   auth->ah_private = (caddr_t) ad;
 190
 191   if (!authdes_refresh (auth))
 192     goto failed;
 193
 194   return (auth);
 195
 196 failed:
 197   if (auth != NULL)
 198     FREE (auth, sizeof (AUTH));
 199   if (ad != NULL)
 200     {
 201       if (ad->ad_fullname != NULL)
 202         FREE (ad->ad_fullname, ad->ad_fullnamelen + 1);
 203       if (ad->ad_servername != NULL)
 204         FREE (ad->ad_servername, ad->ad_servernamelen + 1);
 205       FREE (ad, sizeof (struct ad_private));
 206     }
 207   return (NULL);
 208 }
 209
 210 /*
 211  * Implement the five authentication operations
 212  */
 213
 214
 215 /*
 216  * 1. Next Verifier
 217  */
 218 /*ARGSUSED */
 219 static void
 220 authdes_nextverf (AUTH * auth)
 221 {
 222   /* what the heck am I supposed to do??? */
 223 }
 224
 225
 226
 227 /*
 228  * 2. Marshal
 229  */
 230 static bool_t
 231 authdes_marshal (AUTH * auth, XDR * xdrs)
 232 {
 233   struct ad_private *ad = AUTH_PRIVATE (auth);
 234   struct authdes_cred *cred = &ad->ad_cred;
 235   struct authdes_verf *verf = &ad->ad_verf;
 236   des_block cryptbuf[2];
 237   des_block ivec;
 238   int status;
 239   int len;
 240   register long *ixdr;
 241
 242   /*
 243    * Figure out the "time", accounting for any time difference
 244    * with the server if necessary.
 245    */
 246   __gettimeofday (&ad->ad_timestamp, (struct timezone *) NULL);
 247   ad->ad_timestamp.tv_sec += ad->ad_timediff.tv_sec;
 248   ad->ad_timestamp.tv_usec += ad->ad_timediff.tv_usec;
 249   if (ad->ad_timestamp.tv_usec >= MILLION)
 250     {
 251       ad->ad_timestamp.tv_usec -= MILLION;
 252       ad->ad_timestamp.tv_sec += 1;
 253     }
 254
 255   /*
 256    * XDR the timestamp and possibly some other things, then
 257    * encrypt them.
 258    */
 259   ixdr = (long *) cryptbuf;
 260   IXDR_PUT_LONG (ixdr, ad->ad_timestamp.tv_sec);
 261   IXDR_PUT_LONG (ixdr, ad->ad_timestamp.tv_usec);
 262   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 263     {
 264       IXDR_PUT_U_LONG (ixdr, ad->ad_window);
 265       IXDR_PUT_U_LONG (ixdr, ad->ad_window - 1);
 266       ivec.key.high = ivec.key.low = 0;
 267       status = cbc_crypt ((char *) &auth->ah_key, (char *) cryptbuf,
 268               2 * sizeof (des_block), DES_ENCRYPT | DES_HW, (char *) &ivec);
 269     }
 270   else
 271     {
 272       status = ecb_crypt ((char *) &auth->ah_key, (char *) cryptbuf,
 273                           sizeof (des_block), DES_ENCRYPT | DES_HW);
 274     }
 275   if (DES_FAILED (status))
 276     {
 277       debug ("authdes_marshal: DES encryption failure");
 278       return (FALSE);
 279     }
 280   ad->ad_verf.adv_xtimestamp = cryptbuf[0];
 281   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 282     {
 283       ad->ad_cred.adc_fullname.window = cryptbuf[1].key.high;
 284       ad->ad_verf.adv_winverf = cryptbuf[1].key.low;
 285     }
 286   else
 287     {
 288       ad->ad_cred.adc_nickname = ad->ad_nickname;
 289       ad->ad_verf.adv_winverf = 0;
 290     }
 291
 292   /*
 293    * Serialize the credential and verifier into opaque
 294    * authentication data.
 295    */
 296   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 297     {
 298       len = ((1 + 1 + 2 + 1) * BYTES_PER_XDR_UNIT + ad->ad_fullnamelen);
 299     }
 300   else
 301     {
 302       len = (1 + 1) * BYTES_PER_XDR_UNIT;
 303     }
 304
 305   if ((ixdr = xdr_inline (xdrs, 2 * BYTES_PER_XDR_UNIT)) != NULL)
 306     {
 307       IXDR_PUT_LONG (ixdr, AUTH_DES);
 308       IXDR_PUT_LONG (ixdr, len);
 309     }
 310   else
 311     {
 312       ATTEMPT (xdr_putlong (xdrs, (long *)&auth->ah_cred.oa_flavor));
 313       ATTEMPT (xdr_putlong (xdrs, (long *)&len));
 314     }
 315   ATTEMPT (xdr_authdes_cred (xdrs, cred));
 316
 317   len = (2 + 1) * BYTES_PER_XDR_UNIT;
 318   if ((ixdr = xdr_inline (xdrs, 2 * BYTES_PER_XDR_UNIT)) != NULL)
 319     {
 320       IXDR_PUT_LONG (ixdr, AUTH_DES);
 321       IXDR_PUT_LONG (ixdr, len);
 322     }
 323   else
 324     {
 325       ATTEMPT (xdr_putlong (xdrs, (long *)&auth->ah_verf.oa_flavor));
 326       ATTEMPT (xdr_putlong (xdrs, (long *)&len));
 327     }
 328   ATTEMPT (xdr_authdes_verf (xdrs, verf));
 329   return (TRUE);
 330 }
 331
 332
 333 /*
 334  * 3. Validate
 335  */
 336 static bool_t
 337 authdes_validate (AUTH * auth, struct opaque_auth *rverf)
 338 {
 339   struct ad_private *ad = AUTH_PRIVATE (auth);
 340   struct authdes_verf verf;
 341   int status;
 342   register u_long *ixdr;
 343
 344   if (rverf->oa_length != (2 + 1) * BYTES_PER_XDR_UNIT)
 345     return (FALSE);
 346
 347   ixdr = (u_long *) rverf->oa_base;
 348   verf.adv_xtimestamp.key.high = (u_long) * ixdr++;
 349   verf.adv_xtimestamp.key.low = (u_long) * ixdr++;
 350   verf.adv_int_u = (u_long) * ixdr++;   /* nickname not XDR'd ! */
 351
 352   /*
 353    * Decrypt the timestamp
 354    */
 355   status = ecb_crypt ((char *) &auth->ah_key, (char *) &verf.adv_xtimestamp,
 356                       sizeof (des_block), DES_DECRYPT | DES_HW);
 357
 358   if (DES_FAILED (status))
 359     {
 360       debug ("authdes_validate: DES decryption failure");
 361       return (FALSE);
 362     }
 363
 364   /*
 365    * xdr the decrypted timestamp
 366    */
 367   ixdr = (u_long *) verf.adv_xtimestamp.c;
 368   verf.adv_timestamp.tv_sec = IXDR_GET_LONG (ixdr) + 1;
 369   verf.adv_timestamp.tv_usec = IXDR_GET_LONG (ixdr);
 370
 371   /*
 372    * validate
 373    */
 374   if (memcmp ((char *) &ad->ad_timestamp, (char *) &verf.adv_timestamp,
 375               sizeof (struct timeval)) != 0)
 376     {
 377       debug ("authdes_validate: verifier mismatch\n");
 378       return (FALSE);
 379     }
 380
 381   /*
 382    * We have a nickname now, let's use it
 383    */
 384   ad->ad_nickname = verf.adv_nickname;
 385   ad->ad_cred.adc_namekind = ADN_NICKNAME;
 386   return (TRUE);
 387 }
 388
 389 /*
 390  * 4. Refresh
 391  */
 392 static bool_t
 393 authdes_refresh (AUTH * auth)
 394 {
 395   netobj pkey;
 396   struct ad_private *ad = AUTH_PRIVATE (auth);
 397   struct authdes_cred *cred = &ad->ad_cred;
 398
 399   if (ad->ad_dosync &&
 400       !synchronize (&ad->ad_syncaddr, &ad->ad_timediff))
 401     {
 402       /*
 403        * Hope the clocks are synced!
 404        */
 405       ad->ad_timediff.tv_sec = ad->ad_timediff.tv_usec = 0;
 406       debug ("authdes_refresh: unable to synchronize with server");
 407     }
 408   ad->ad_xkey = auth->ah_key;
 409   pkey.n_bytes = (char *) (ad->ad_pkey);
 410   pkey.n_len = strlen ((char *) ad->ad_pkey) + 1;
 411   if (key_encryptsession_pk (ad->ad_servername, &pkey, &ad->ad_xkey) < 0)
 412     {
 413       debug ("authdes_create: unable to encrypt conversation key");
 414       return (FALSE);
 415     }
 416   cred->adc_fullname.key = ad->ad_xkey;
 417   cred->adc_namekind = ADN_FULLNAME;
 418   cred->adc_fullname.name = ad->ad_fullname;
 419   return (TRUE);
 420 }
 421
 422 /*
 423  * 5. Destroy
 424  */
 425 static void
 426 authdes_destroy (AUTH * auth)
 427 {
 428   struct ad_private *ad = AUTH_PRIVATE (auth);
 429
 430   FREE (ad->ad_fullname, ad->ad_fullnamelen + 1);
 431   FREE (ad->ad_servername, ad->ad_servernamelen + 1);
 432   FREE (ad, sizeof (struct ad_private));
 433   FREE (auth, sizeof (AUTH));
 434 }
 435
 436 /*
 437  * Synchronize with the server at the given address, that is,
 438  * adjust timep to reflect the delta between our clocks
 439  */
 440 static bool_t
 441 internal_function
 442 synchronize (struct sockaddr *syncaddr, struct timeval *timep)
 443 {
 444   struct timeval mytime;
 445   struct timeval timeout;
 446
 447   timeout.tv_sec = RTIME_TIMEOUT;
 448   timeout.tv_usec = 0;
 449   if (rtime ((struct sockaddr_in *) syncaddr, timep, &timeout) < 0)
 450     return (FALSE);
 451
 452   __gettimeofday (&mytime, (struct timezone *) NULL);
 453   timep->tv_sec -= mytime.tv_sec;
 454   if (mytime.tv_usec > timep->tv_usec)
 455     {
 456       timep->tv_sec -= 1;
 457       timep->tv_usec += MILLION;
 458     }
 459   timep->tv_usec -= mytime.tv_usec;
 460   return (TRUE);
 461 }