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   authdes_nextverf,
  75   authdes_marshal,
  76   authdes_validate,
  77   authdes_refresh,
  78   authdes_destroy
  79 };
  80
  81
  82 /*
  83  * This struct is pointed to by the ah_private field of an "AUTH *"
  84  */
  85 struct ad_private {
  86   char *ad_fullname;            /* client's full name */
  87   u_int ad_fullnamelen;         /* length of name, rounded up */
  88   char *ad_servername;          /* server's full name */
  89   u_int ad_servernamelen;       /* length of name, rounded up */
  90   uint32_t ad_window;           /* client specified window */
  91   bool_t ad_dosync;             /* synchronize? */
  92   struct sockaddr ad_syncaddr;  /* remote host to synch with */
  93   struct timeval ad_timediff;   /* server's time - client's time */
  94   u_long ad_nickname;           /* server's nickname for client */
  95   struct authdes_cred ad_cred;  /* storage for credential */
  96   struct authdes_verf ad_verf;  /* storage for verifier */
  97   struct timeval ad_timestamp;  /* timestamp sent */
  98   des_block ad_xkey;            /* encrypted conversation key */
  99   u_char ad_pkey[1024];         /* Servers actual public key */
 100 };
 101
 102
 103 /*
 104  * Create the client des authentication object
 105  */
 106 AUTH *
 107 authdes_create (const char *servername, u_int window,
 108                 struct sockaddr *syncaddr, des_block *ckey)
 109   /* servername - network name of server */
 110   /* window     - time to live */
 111   /* syncaddr   - optional addr of host to sync with */
 112   /* ckey       - optional conversation key to use */
 113 {
 114   u_char pkey_data[1024];
 115   netobj pkey;
 116
 117   if (!getpublickey (servername, pkey_data))
 118     return (NULL);
 119
 120   pkey.n_bytes = (char *) pkey_data;
 121   pkey.n_len = strlen ((char *) pkey_data) + 1;
 122   return authdes_pk_create (servername, &pkey, window, syncaddr, ckey);
 123 }
 124
 125 AUTH *
 126 authdes_pk_create (const char *servername, netobj *pkey, u_int window,
 127                    struct sockaddr *syncaddr, des_block *ckey)
 128 {
 129   AUTH *auth;
 130   struct ad_private *ad;
 131   char namebuf[MAXNETNAMELEN + 1];
 132
 133   /*
 134    * Allocate everything now
 135    */
 136   auth = ALLOC (AUTH);
 137   ad = ALLOC (struct ad_private);
 138   memset (ad, 0, sizeof (struct ad_private));
 139   memcpy (ad->ad_pkey, pkey->n_bytes, pkey->n_len);
 140   if (!getnetname (namebuf))
 141     goto failed;
 142   ad->ad_fullnamelen = RNDUP (strlen (namebuf));
 143   ad->ad_fullname = mem_alloc (ad->ad_fullnamelen + 1);
 144
 145   ad->ad_servernamelen = strlen (servername);
 146   ad->ad_servername = mem_alloc (ad->ad_servernamelen + 1);
 147
 148   if (auth == NULL || ad == NULL || ad->ad_fullname == NULL ||
 149       ad->ad_servername == NULL)
 150     {
 151       debug ("authdes_create: out of memory");
 152       goto failed;
 153     }
 154
 155   /*
 156    * Set up private data
 157    */
 158   bcopy (namebuf, ad->ad_fullname, ad->ad_fullnamelen + 1);
 159   bcopy (servername, ad->ad_servername, ad->ad_servernamelen + 1);
 160   ad->ad_timediff.tv_sec = ad->ad_timediff.tv_usec = 0;
 161   if (syncaddr != NULL)
 162     {
 163       ad->ad_syncaddr = *syncaddr;
 164       ad->ad_dosync = TRUE;
 165     }
 166   else
 167     ad->ad_dosync = FALSE;
 168
 169   ad->ad_window = window;
 170   if (ckey == NULL)
 171     {
 172       if (key_gendes (&auth->ah_key) < 0)
 173         {
 174           debug ("authdes_create: unable to gen conversation key");
 175           return (NULL);
 176         }
 177     }
 178   else
 179     auth->ah_key = *ckey;
 180
 181   /*
 182    * Set up auth handle
 183    */
 184   auth->ah_cred.oa_flavor = AUTH_DES;
 185   auth->ah_verf.oa_flavor = AUTH_DES;
 186   auth->ah_ops = &authdes_ops;
 187   auth->ah_private = (caddr_t) ad;
 188
 189   if (!authdes_refresh (auth))
 190     goto failed;
 191
 192   return (auth);
 193
 194 failed:
 195   if (auth != NULL)
 196     FREE (auth, sizeof (AUTH));
 197   if (ad != NULL)
 198     {
 199       if (ad->ad_fullname != NULL)
 200         FREE (ad->ad_fullname, ad->ad_fullnamelen + 1);
 201       if (ad->ad_servername != NULL)
 202         FREE (ad->ad_servername, ad->ad_servernamelen + 1);
 203       FREE (ad, sizeof (struct ad_private));
 204     }
 205   return (NULL);
 206 }
 207
 208 /*
 209  * Implement the five authentication operations
 210  */
 211
 212
 213 /*
 214  * 1. Next Verifier
 215  */
 216 /*ARGSUSED */
 217 static void
 218 authdes_nextverf (AUTH * auth)
 219 {
 220   /* what the heck am I supposed to do??? */
 221 }
 222
 223
 224
 225 /*
 226  * 2. Marshal
 227  */
 228 static bool_t
 229 authdes_marshal (AUTH * auth, XDR * xdrs)
 230 {
 231   struct ad_private *ad = AUTH_PRIVATE (auth);
 232   struct authdes_cred *cred = &ad->ad_cred;
 233   struct authdes_verf *verf = &ad->ad_verf;
 234   des_block cryptbuf[2];
 235   des_block ivec;
 236   int status;
 237   unsigned int len;
 238   register long *ixdr;
 239
 240   /*
 241    * Figure out the "time", accounting for any time difference
 242    * with the server if necessary.
 243    */
 244   __gettimeofday (&ad->ad_timestamp, (struct timezone *) NULL);
 245   ad->ad_timestamp.tv_sec += ad->ad_timediff.tv_sec;
 246   ad->ad_timestamp.tv_usec += ad->ad_timediff.tv_usec;
 247   if (ad->ad_timestamp.tv_usec >= MILLION)
 248     {
 249       ad->ad_timestamp.tv_usec -= MILLION;
 250       ad->ad_timestamp.tv_sec += 1;
 251     }
 252
 253   /*
 254    * XDR the timestamp and possibly some other things, then
 255    * encrypt them.
 256    * XXX We have a real Year 2038 problem here.
 257    */
 258   ixdr = (long *) cryptbuf;
 259   IXDR_PUT_LONG (ixdr, ad->ad_timestamp.tv_sec);
 260   IXDR_PUT_LONG (ixdr, ad->ad_timestamp.tv_usec);
 261   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 262     {
 263       IXDR_PUT_U_INT32 (ixdr, ad->ad_window);
 264       IXDR_PUT_U_INT32 (ixdr, ad->ad_window - 1);
 265       ivec.key.high = ivec.key.low = 0;
 266       status = cbc_crypt ((char *) &auth->ah_key, (char *) cryptbuf,
 267               2 * sizeof (des_block), DES_ENCRYPT | DES_HW, (char *) &ivec);
 268     }
 269   else
 270     {
 271       status = ecb_crypt ((char *) &auth->ah_key, (char *) cryptbuf,
 272                           sizeof (des_block), DES_ENCRYPT | DES_HW);
 273     }
 274   if (DES_FAILED (status))
 275     {
 276       debug ("authdes_marshal: DES encryption failure");
 277       return (FALSE);
 278     }
 279   ad->ad_verf.adv_xtimestamp = cryptbuf[0];
 280   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 281     {
 282       ad->ad_cred.adc_fullname.window = cryptbuf[1].key.high;
 283       ad->ad_verf.adv_winverf = cryptbuf[1].key.low;
 284     }
 285   else
 286     {
 287       ad->ad_cred.adc_nickname = ad->ad_nickname;
 288       ad->ad_verf.adv_winverf = 0;
 289     }
 290
 291   /*
 292    * Serialize the credential and verifier into opaque
 293    * authentication data.
 294    */
 295   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 296     {
 297       len = ((1 + 1 + 2 + 1) * BYTES_PER_XDR_UNIT + ad->ad_fullnamelen);
 298     }
 299   else
 300     {
 301       len = (1 + 1) * BYTES_PER_XDR_UNIT;
 302     }
 303
 304   if ((ixdr = xdr_inline (xdrs, 2 * BYTES_PER_XDR_UNIT)) != NULL)
 305     {
 306       IXDR_PUT_INT32 (ixdr, AUTH_DES);
 307       IXDR_PUT_U_INT32 (ixdr, len);
 308     }
 309   else
 310     {
 311       ATTEMPT (xdr_putint32 (xdrs, &auth->ah_cred.oa_flavor));
 312       ATTEMPT (xdr_putint32 (xdrs, &len));
 313     }
 314   ATTEMPT (xdr_authdes_cred (xdrs, cred));
 315
 316   len = (2 + 1) * BYTES_PER_XDR_UNIT;
 317   if ((ixdr = xdr_inline (xdrs, 2 * BYTES_PER_XDR_UNIT)) != NULL)
 318     {
 319       IXDR_PUT_INT32 (ixdr, AUTH_DES);
 320       IXDR_PUT_U_INT32 (ixdr, len);
 321     }
 322   else
 323     {
 324       ATTEMPT (xdr_putint32 (xdrs, &auth->ah_verf.oa_flavor));
 325       ATTEMPT (xdr_putint32 (xdrs, &len));
 326     }
 327   ATTEMPT (xdr_authdes_verf (xdrs, verf));
 328   return TRUE;
 329 }
 330
 331
 332 /*
 333  * 3. Validate
 334  */
 335 static bool_t
 336 authdes_validate (AUTH *auth, struct opaque_auth *rverf)
 337 {
 338   struct ad_private *ad = AUTH_PRIVATE (auth);
 339   struct authdes_verf verf;
 340   int status;
 341   register u_long *ixdr;
 342
 343   if (rverf->oa_length != (2 + 1) * BYTES_PER_XDR_UNIT)
 344     return (FALSE);
 345
 346   ixdr = (u_long *) rverf->oa_base;
 347   verf.adv_xtimestamp.key.high = (u_long) * ixdr++;
 348   verf.adv_xtimestamp.key.low = (u_long) * ixdr++;
 349   verf.adv_int_u = (u_long) * ixdr++;   /* nickname not XDR'd ! */
 350
 351   /*
 352    * Decrypt the timestamp
 353    */
 354   status = ecb_crypt ((char *) &auth->ah_key, (char *) &verf.adv_xtimestamp,
 355                       sizeof (des_block), DES_DECRYPT | DES_HW);
 356
 357   if (DES_FAILED (status))
 358     {
 359       debug ("authdes_validate: DES decryption failure");
 360       return FALSE;
 361     }
 362
 363   /*
 364    * xdr the decrypted timestamp
 365    */
 366   ixdr = (u_long *) verf.adv_xtimestamp.c;
 367   verf.adv_timestamp.tv_sec = IXDR_GET_LONG (ixdr) + 1;
 368   verf.adv_timestamp.tv_usec = IXDR_GET_LONG (ixdr);
 369
 370   /*
 371    * validate
 372    */
 373   if (memcmp ((char *) &ad->ad_timestamp, (char *) &verf.adv_timestamp,
 374               sizeof (struct timeval)) != 0)
 375     {
 376       debug ("authdes_validate: verifier mismatch\n");
 377       return FALSE;
 378     }
 379
 380   /*
 381    * We have a nickname now, let's use it
 382    */
 383   ad->ad_nickname = verf.adv_nickname;
 384   ad->ad_cred.adc_namekind = ADN_NICKNAME;
 385   return TRUE;
 386 }
 387
 388 /*
 389  * 4. Refresh
 390  */
 391 static bool_t
 392 authdes_refresh (AUTH *auth)
 393 {
 394   netobj pkey;
 395   struct ad_private *ad = AUTH_PRIVATE (auth);
 396   struct authdes_cred *cred = &ad->ad_cred;
 397
 398   if (ad->ad_dosync &&
 399       !synchronize (&ad->ad_syncaddr, &ad->ad_timediff))
 400     {
 401       /*
 402        * Hope the clocks are synced!
 403        */
 404       ad->ad_timediff.tv_sec = ad->ad_timediff.tv_usec = 0;
 405       debug ("authdes_refresh: unable to synchronize with server");
 406     }
 407   ad->ad_xkey = auth->ah_key;
 408   pkey.n_bytes = (char *) (ad->ad_pkey);
 409   pkey.n_len = strlen ((char *) ad->ad_pkey) + 1;
 410   if (key_encryptsession_pk (ad->ad_servername, &pkey, &ad->ad_xkey) < 0)
 411     {
 412       debug ("authdes_create: unable to encrypt conversation key");
 413       return FALSE;
 414     }
 415   cred->adc_fullname.key = ad->ad_xkey;
 416   cred->adc_namekind = ADN_FULLNAME;
 417   cred->adc_fullname.name = ad->ad_fullname;
 418   return TRUE;
 419 }
 420
 421 /*
 422  * 5. Destroy
 423  */
 424 static void
 425 authdes_destroy (AUTH *auth)
 426 {
 427   struct ad_private *ad = AUTH_PRIVATE (auth);
 428
 429   FREE (ad->ad_fullname, ad->ad_fullnamelen + 1);
 430   FREE (ad->ad_servername, ad->ad_servernamelen + 1);
 431   FREE (ad, sizeof (struct ad_private));
 432   FREE (auth, sizeof (AUTH));
 433 }
 434
 435 /*
 436  * Synchronize with the server at the given address, that is,
 437  * adjust timep to reflect the delta between our clocks
 438  */
 439 static bool_t
 440 internal_function
 441 synchronize (struct sockaddr *syncaddr, struct timeval *timep)
 442 {
 443   struct timeval mytime;
 444   struct timeval timeout;
 445
 446   timeout.tv_sec = RTIME_TIMEOUT;
 447   timeout.tv_usec = 0;
 448   if (rtime ((struct sockaddr_in *) syncaddr, timep, &timeout) < 0)
 449     return FALSE;
 450
 451   __gettimeofday (&mytime, (struct timezone *) NULL);
 452   timep->tv_sec -= mytime.tv_sec;
 453   if (mytime.tv_usec > timep->tv_usec)
 454     {
 455       timep->tv_sec -= 1;
 456       timep->tv_usec += MILLION;
 457     }
 458   timep->tv_usec -= mytime.tv_usec;
 459   return TRUE;
 460 }