sunrpc/auth_des.c

   1 /*
   2  * Copyright (c) 2010, Oracle America, Inc.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions are
   6  * met:
   7  *
   8  *     * Redistributions of source code must retain the above copyright
   9  *       notice, this list of conditions and the following disclaimer.
  10  *     * Redistributions in binary form must reproduce the above
  11  *       copyright notice, this list of conditions and the following
  12  *       disclaimer in the documentation and/or other materials
  13  *       provided with the distribution.
  14  *     * Neither the name of the "Oracle America, Inc." nor the names of its
  15  *       contributors may be used to endorse or promote products derived
  16  *       from this software without specific prior written permission.
  17  *
  18  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  19  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  20  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  21  *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  22  *   COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
  23  *   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  *   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  25  *   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  27  *   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  28  *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  29  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30  */
  31 /*
  32  * auth_des.c, client-side implementation of DES authentication
  33  */
  34
  35 #include <string.h>
  36 #include <stdint.h>
  37 #include <rpc/des_crypt.h>
  38 #include <rpc/types.h>
  39 #include <rpc/auth.h>
  40 #include <rpc/auth_des.h>
  41 #include <rpc/xdr.h>
  42 #include <netinet/in.h>         /* XXX: just to get htonl() and ntohl() */
  43 #include <sys/socket.h>
  44 #include <shlib-compat.h>
  45
  46 #define MILLION         1000000L
  47 #define RTIME_TIMEOUT 5         /* seconds to wait for sync */
  48
  49 #define AUTH_PRIVATE(auth)      (struct ad_private *) auth->ah_private
  50 #define ALLOC(object_type)      (object_type *) mem_alloc(sizeof(object_type))
  51 #define FREE(ptr, size)         mem_free((char *)(ptr), (int) size)
  52 #define ATTEMPT(xdr_op)         if (!(xdr_op)) return (FALSE)
  53
  54 #define debug(msg)              /* printf("%s\n", msg) */
  55
  56
  57 /*
  58  * DES authenticator operations vector
  59  */
  60 static void authdes_nextverf (AUTH *);
  61 static bool_t authdes_marshal (AUTH *, XDR *);
  62 static bool_t authdes_validate (AUTH *, struct opaque_auth *);
  63 static bool_t authdes_refresh (AUTH *);
  64 static void authdes_destroy (AUTH *);
  65 static bool_t synchronize (struct sockaddr *, struct rpc_timeval *)
  66      internal_function;
  67
  68 static const struct auth_ops authdes_ops = {
  69   authdes_nextverf,
  70   authdes_marshal,
  71   authdes_validate,
  72   authdes_refresh,
  73   authdes_destroy
  74 };
  75
  76
  77 /*
  78  * This struct is pointed to by the ah_private field of an "AUTH *"
  79  */
  80 struct ad_private {
  81   char *ad_fullname;            /* client's full name */
  82   u_int ad_fullnamelen;         /* length of name, rounded up */
  83   char *ad_servername;          /* server's full name */
  84   u_int ad_servernamelen;       /* length of name, rounded up */
  85   uint32_t ad_window;           /* client specified window */
  86   bool_t ad_dosync;             /* synchronize? */
  87   struct sockaddr ad_syncaddr;  /* remote host to synch with */
  88   struct rpc_timeval ad_timediff;       /* server's time - client's time */
  89   uint32_t ad_nickname;         /* server's nickname for client */
  90   struct authdes_cred ad_cred;  /* storage for credential */
  91   struct authdes_verf ad_verf;  /* storage for verifier */
  92   struct rpc_timeval ad_timestamp;      /* timestamp sent */
  93   des_block ad_xkey;            /* encrypted conversation key */
  94   u_char ad_pkey[1024];         /* Servers actual public key */
  95 };
  96
  97
  98 /*
  99  * Create the client des authentication object
 100  */
 101 AUTH *
 102 authdes_create (const char *servername, u_int window,
 103                 struct sockaddr *syncaddr, des_block *ckey)
 104   /* servername - network name of server */
 105   /* window     - time to live */
 106   /* syncaddr   - optional addr of host to sync with */
 107   /* ckey       - optional conversation key to use */
 108 {
 109   char pkey_data[1024];
 110   netobj pkey;
 111
 112   if (!getpublickey (servername, pkey_data))
 113     return NULL;
 114
 115   pkey.n_bytes = pkey_data;
 116   pkey.n_len = strlen (pkey_data) + 1;
 117   return authdes_pk_create (servername, &pkey, window, syncaddr, ckey);
 118 }
 119 #ifdef EXPORT_RPC_SYMBOLS
 120 libc_hidden_def (authdes_create)
 121 #else
 122 libc_hidden_nolink_sunrpc (authdes_create, GLIBC_2_1)
 123 #endif
 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
 139   if (auth == NULL || ad == NULL)
 140     {
 141       debug ("authdes_create: out of memory");
 142       goto failed;
 143     }
 144
 145   memset (ad, 0, sizeof (struct ad_private));
 146   memcpy (ad->ad_pkey, pkey->n_bytes, pkey->n_len);
 147   if (!getnetname (namebuf))
 148     goto failed;
 149   ad->ad_fullnamelen = RNDUP (strlen (namebuf));
 150   ad->ad_fullname = mem_alloc (ad->ad_fullnamelen + 1);
 151
 152   ad->ad_servernamelen = strlen (servername);
 153   ad->ad_servername = mem_alloc (ad->ad_servernamelen + 1);
 154
 155   if (ad->ad_fullname == NULL || 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   memcpy (ad->ad_fullname, namebuf, ad->ad_fullnamelen + 1);
 165   memcpy (ad->ad_servername, 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           goto failed;
 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 = (struct auth_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 #ifdef EXPORT_RPC_SYMBOLS
 214 libc_hidden_def (authdes_pk_create)
 215 #else
 216 libc_hidden_nolink_sunrpc (authdes_pk_create, GLIBC_2_1)
 217 #endif
 218
 219 /*
 220  * Implement the five authentication operations
 221  */
 222
 223
 224 /*
 225  * 1. Next Verifier
 226  */
 227 /*ARGSUSED */
 228 static void
 229 authdes_nextverf (AUTH *auth)
 230 {
 231   /* what the heck am I supposed to do??? */
 232 }
 233
 234
 235
 236 /*
 237  * 2. Marshal
 238  */
 239 static bool_t
 240 authdes_marshal (AUTH *auth, XDR *xdrs)
 241 {
 242   struct ad_private *ad = AUTH_PRIVATE (auth);
 243   struct authdes_cred *cred = &ad->ad_cred;
 244   struct authdes_verf *verf = &ad->ad_verf;
 245   des_block cryptbuf[2];
 246   des_block ivec;
 247   int status;
 248   int len;
 249   register int32_t *ixdr;
 250   struct timeval tval;
 251
 252   /*
 253    * Figure out the "time", accounting for any time difference
 254    * with the server if necessary.
 255    */
 256   __gettimeofday (&tval, (struct timezone *) NULL);
 257   ad->ad_timestamp.tv_sec = tval.tv_sec + ad->ad_timediff.tv_sec;
 258   ad->ad_timestamp.tv_usec = tval.tv_usec + ad->ad_timediff.tv_usec;
 259   if (ad->ad_timestamp.tv_usec >= MILLION)
 260     {
 261       ad->ad_timestamp.tv_usec -= MILLION;
 262       ad->ad_timestamp.tv_sec += 1;
 263     }
 264
 265   /*
 266    * XDR the timestamp and possibly some other things, then
 267    * encrypt them.
 268    * XXX We have a real Year 2038 problem here.
 269    */
 270   ixdr = (int32_t *) cryptbuf;
 271   IXDR_PUT_INT32 (ixdr, ad->ad_timestamp.tv_sec);
 272   IXDR_PUT_INT32 (ixdr, ad->ad_timestamp.tv_usec);
 273   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 274     {
 275       IXDR_PUT_U_INT32 (ixdr, ad->ad_window);
 276       IXDR_PUT_U_INT32 (ixdr, ad->ad_window - 1);
 277       ivec.key.high = ivec.key.low = 0;
 278       status = cbc_crypt ((char *) &auth->ah_key, (char *) cryptbuf,
 279               2 * sizeof (des_block), DES_ENCRYPT | DES_HW, (char *) &ivec);
 280     }
 281   else
 282     status = ecb_crypt ((char *) &auth->ah_key, (char *) cryptbuf,
 283                         sizeof (des_block), DES_ENCRYPT | DES_HW);
 284
 285   if (DES_FAILED (status))
 286     {
 287       debug ("authdes_marshal: DES encryption failure");
 288       return FALSE;
 289     }
 290   ad->ad_verf.adv_xtimestamp = cryptbuf[0];
 291   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 292     {
 293       ad->ad_cred.adc_fullname.window = cryptbuf[1].key.high;
 294       ad->ad_verf.adv_winverf = cryptbuf[1].key.low;
 295     }
 296   else
 297     {
 298       ad->ad_cred.adc_nickname = ad->ad_nickname;
 299       ad->ad_verf.adv_winverf = 0;
 300     }
 301
 302   /*
 303    * Serialize the credential and verifier into opaque
 304    * authentication data.
 305    */
 306   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 307     len = ((1 + 1 + 2 + 1) * BYTES_PER_XDR_UNIT + ad->ad_fullnamelen);
 308   else
 309     len = (1 + 1) * BYTES_PER_XDR_UNIT;
 310
 311   if ((ixdr = xdr_inline (xdrs, 2 * BYTES_PER_XDR_UNIT)) != NULL)
 312     {
 313       IXDR_PUT_INT32 (ixdr, AUTH_DES);
 314       IXDR_PUT_U_INT32 (ixdr, len);
 315     }
 316   else
 317     {
 318       ATTEMPT (xdr_putint32 (xdrs, &auth->ah_cred.oa_flavor));
 319       ATTEMPT (xdr_putint32 (xdrs, &len));
 320     }
 321   ATTEMPT (xdr_authdes_cred (xdrs, cred));
 322
 323   len = (2 + 1) * BYTES_PER_XDR_UNIT;
 324   if ((ixdr = xdr_inline (xdrs, 2 * BYTES_PER_XDR_UNIT)) != NULL)
 325     {
 326       IXDR_PUT_INT32 (ixdr, AUTH_DES);
 327       IXDR_PUT_U_INT32 (ixdr, len);
 328     }
 329   else
 330     {
 331       ATTEMPT (xdr_putint32 (xdrs, &auth->ah_verf.oa_flavor));
 332       ATTEMPT (xdr_putint32 (xdrs, &len));
 333     }
 334   ATTEMPT (xdr_authdes_verf (xdrs, verf));
 335
 336   return TRUE;
 337 }
 338
 339
 340 /*
 341  * 3. Validate
 342  */
 343 static bool_t
 344 authdes_validate (AUTH *auth, struct opaque_auth *rverf)
 345 {
 346   struct ad_private *ad = AUTH_PRIVATE (auth);
 347   struct authdes_verf verf;
 348   int status;
 349   register uint32_t *ixdr;
 350
 351   if (rverf->oa_length != (2 + 1) * BYTES_PER_XDR_UNIT)
 352     return FALSE;
 353
 354   ixdr = (uint32_t *) rverf->oa_base;
 355   verf.adv_xtimestamp.key.high = *ixdr++;
 356   verf.adv_xtimestamp.key.low = *ixdr++;
 357   verf.adv_int_u = *ixdr++;     /* nickname not XDR'd ! */
 358
 359   /*
 360    * Decrypt the timestamp
 361    */
 362   status = ecb_crypt ((char *) &auth->ah_key, (char *) &verf.adv_xtimestamp,
 363                       sizeof (des_block), DES_DECRYPT | DES_HW);
 364
 365   if (DES_FAILED (status))
 366     {
 367       debug ("authdes_validate: DES decryption failure");
 368       return FALSE;
 369     }
 370
 371   /*
 372    * xdr the decrypted timestamp
 373    */
 374   ixdr = (uint32_t *) verf.adv_xtimestamp.c;
 375   verf.adv_timestamp.tv_sec = IXDR_GET_U_INT32 (ixdr) + 1;
 376   verf.adv_timestamp.tv_usec = IXDR_GET_U_INT32 (ixdr);
 377
 378   /*
 379    * validate
 380    */
 381   if (memcmp ((char *) &ad->ad_timestamp, (char *) &verf.adv_timestamp,
 382               sizeof (struct rpc_timeval)) != 0)
 383     {
 384       debug ("authdes_validate: verifier mismatch\n");
 385       return FALSE;
 386     }
 387
 388   /*
 389    * We have a nickname now, let's use it
 390    */
 391   ad->ad_nickname = verf.adv_nickname;
 392   ad->ad_cred.adc_namekind = ADN_NICKNAME;
 393   return TRUE;
 394 }
 395
 396 /*
 397  * 4. Refresh
 398  */
 399 static bool_t
 400 authdes_refresh (AUTH *auth)
 401 {
 402   netobj pkey;
 403   struct ad_private *ad = AUTH_PRIVATE (auth);
 404   struct authdes_cred *cred = &ad->ad_cred;
 405
 406   if (ad->ad_dosync && !synchronize (&ad->ad_syncaddr, &ad->ad_timediff))
 407     {
 408       /*
 409        * Hope the clocks are synced!
 410        */
 411       ad->ad_timediff.tv_sec = ad->ad_timediff.tv_usec = 0;
 412       debug ("authdes_refresh: unable to synchronize with server");
 413     }
 414   ad->ad_xkey = auth->ah_key;
 415   pkey.n_bytes = (char *) (ad->ad_pkey);
 416   pkey.n_len = strlen ((char *) ad->ad_pkey) + 1;
 417   if (key_encryptsession_pk (ad->ad_servername, &pkey, &ad->ad_xkey) < 0)
 418     {
 419       debug ("authdes_create: unable to encrypt conversation key");
 420       return FALSE;
 421     }
 422   cred->adc_fullname.key = ad->ad_xkey;
 423   cred->adc_namekind = ADN_FULLNAME;
 424   cred->adc_fullname.name = ad->ad_fullname;
 425   return TRUE;
 426 }
 427
 428 /*
 429  * 5. Destroy
 430  */
 431 static void
 432 authdes_destroy (AUTH *auth)
 433 {
 434   struct ad_private *ad = AUTH_PRIVATE (auth);
 435
 436   FREE (ad->ad_fullname, ad->ad_fullnamelen + 1);
 437   FREE (ad->ad_servername, ad->ad_servernamelen + 1);
 438   FREE (ad, sizeof (struct ad_private));
 439   FREE (auth, sizeof (AUTH));
 440 }
 441
 442 /*
 443  * Synchronize with the server at the given address, that is,
 444  * adjust timep to reflect the delta between our clocks
 445  */
 446 static bool_t
 447 internal_function
 448 synchronize (struct sockaddr *syncaddr, struct rpc_timeval *timep)
 449 {
 450   struct timeval mytime;
 451   struct rpc_timeval timeout;
 452
 453   timeout.tv_sec = RTIME_TIMEOUT;
 454   timeout.tv_usec = 0;
 455   if (rtime ((struct sockaddr_in *) syncaddr, timep, &timeout) < 0)
 456     return FALSE;
 457
 458   __gettimeofday (&mytime, (struct timezone *) NULL);
 459   timep->tv_sec -= mytime.tv_sec;
 460   if (mytime.tv_usec > timep->tv_usec)
 461     {
 462       timep->tv_sec -= 1;
 463       timep->tv_usec += MILLION;
 464     }
 465   timep->tv_usec -= mytime.tv_usec;
 466   return TRUE;
 467 }