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
  45 #define MILLION         1000000L
  46 #define RTIME_TIMEOUT 5         /* seconds to wait for sync */
  47
  48 #define AUTH_PRIVATE(auth)      (struct ad_private *) auth->ah_private
  49 #define ALLOC(object_type)      (object_type *) mem_alloc(sizeof(object_type))
  50 #define FREE(ptr, size)         mem_free((char *)(ptr), (int) size)
  51 #define ATTEMPT(xdr_op)         if (!(xdr_op)) return (FALSE)
  52
  53 #define debug(msg)              /* printf("%s\n", msg) */
  54
  55
  56 /*
  57  * DES authenticator operations vector
  58  */
  59 static void authdes_nextverf (AUTH *);
  60 static bool_t authdes_marshal (AUTH *, XDR *);
  61 static bool_t authdes_validate (AUTH *, struct opaque_auth *);
  62 static bool_t authdes_refresh (AUTH *);
  63 static void authdes_destroy (AUTH *);
  64 static bool_t synchronize (struct sockaddr *, struct rpc_timeval *)
  65      internal_function;
  66
  67 static const struct auth_ops authdes_ops = {
  68   authdes_nextverf,
  69   authdes_marshal,
  70   authdes_validate,
  71   authdes_refresh,
  72   authdes_destroy
  73 };
  74
  75
  76 /*
  77  * This struct is pointed to by the ah_private field of an "AUTH *"
  78  */
  79 struct ad_private {
  80   char *ad_fullname;            /* client's full name */
  81   u_int ad_fullnamelen;         /* length of name, rounded up */
  82   char *ad_servername;          /* server's full name */
  83   u_int ad_servernamelen;       /* length of name, rounded up */
  84   uint32_t ad_window;           /* client specified window */
  85   bool_t ad_dosync;             /* synchronize? */
  86   struct sockaddr ad_syncaddr;  /* remote host to synch with */
  87   struct rpc_timeval ad_timediff;       /* server's time - client's time */
  88   uint32_t ad_nickname;         /* server's nickname for client */
  89   struct authdes_cred ad_cred;  /* storage for credential */
  90   struct authdes_verf ad_verf;  /* storage for verifier */
  91   struct rpc_timeval ad_timestamp;      /* timestamp sent */
  92   des_block ad_xkey;            /* encrypted conversation key */
  93   u_char ad_pkey[1024];         /* Servers actual public key */
  94 };
  95
  96
  97 /*
  98  * Create the client des authentication object
  99  */
 100 AUTH *
 101 authdes_create (const char *servername, u_int window,
 102                 struct sockaddr *syncaddr, des_block *ckey)
 103   /* servername - network name of server */
 104   /* window     - time to live */
 105   /* syncaddr   - optional addr of host to sync with */
 106   /* ckey       - optional conversation key to use */
 107 {
 108   char pkey_data[1024];
 109   netobj pkey;
 110
 111   if (!getpublickey (servername, pkey_data))
 112     return NULL;
 113
 114   pkey.n_bytes = pkey_data;
 115   pkey.n_len = strlen (pkey_data) + 1;
 116   return authdes_pk_create (servername, &pkey, window, syncaddr, ckey);
 117 }
 118 #ifdef EXPORT_RPC_SYMBOLS
 119 libc_hidden_def (authdes_create)
 120 #else
 121 libc_hidden_nolink_sunrpc (authdes_create, GLIBC_2_1)
 122 #endif
 123
 124 AUTH *
 125 authdes_pk_create (const char *servername, netobj *pkey, u_int window,
 126                    struct sockaddr *syncaddr, des_block *ckey)
 127 {
 128   AUTH *auth;
 129   struct ad_private *ad;
 130   char namebuf[MAXNETNAMELEN + 1];
 131
 132   /*
 133    * Allocate everything now
 134    */
 135   auth = ALLOC (AUTH);
 136   ad = ALLOC (struct ad_private);
 137
 138   if (auth == NULL || ad == NULL)
 139     {
 140       debug ("authdes_create: out of memory");
 141       goto failed;
 142     }
 143
 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 (ad->ad_fullname == NULL || ad->ad_servername == NULL)
 155     {
 156       debug ("authdes_create: out of memory");
 157       goto failed;
 158     }
 159
 160   /*
 161    * Set up private data
 162    */
 163   memcpy (ad->ad_fullname, namebuf, ad->ad_fullnamelen + 1);
 164   memcpy (ad->ad_servername, servername, ad->ad_servernamelen + 1);
 165   ad->ad_timediff.tv_sec = ad->ad_timediff.tv_usec = 0;
 166   if (syncaddr != NULL)
 167     {
 168       ad->ad_syncaddr = *syncaddr;
 169       ad->ad_dosync = TRUE;
 170     }
 171   else
 172     ad->ad_dosync = FALSE;
 173
 174   ad->ad_window = window;
 175   if (ckey == NULL)
 176     {
 177       if (key_gendes (&auth->ah_key) < 0)
 178         {
 179           debug ("authdes_create: unable to gen conversation key");
 180           goto failed;
 181         }
 182     }
 183   else
 184     auth->ah_key = *ckey;
 185
 186   /*
 187    * Set up auth handle
 188    */
 189   auth->ah_cred.oa_flavor = AUTH_DES;
 190   auth->ah_verf.oa_flavor = AUTH_DES;
 191   auth->ah_ops = (struct auth_ops *) &authdes_ops;
 192   auth->ah_private = (caddr_t) ad;
 193
 194   if (!authdes_refresh (auth))
 195     goto failed;
 196
 197   return auth;
 198
 199 failed:
 200   if (auth != NULL)
 201     FREE (auth, sizeof (AUTH));
 202   if (ad != NULL)
 203     {
 204       if (ad->ad_fullname != NULL)
 205         FREE (ad->ad_fullname, ad->ad_fullnamelen + 1);
 206       if (ad->ad_servername != NULL)
 207         FREE (ad->ad_servername, ad->ad_servernamelen + 1);
 208       FREE (ad, sizeof (struct ad_private));
 209     }
 210   return NULL;
 211 }
 212 #ifdef EXPORT_RPC_SYMBOLS
 213 libc_hidden_def (authdes_pk_create)
 214 #else
 215 libc_hidden_nolink_sunrpc (authdes_pk_create, GLIBC_2_1)
 216 #endif
 217
 218 /*
 219  * Implement the five authentication operations
 220  */
 221
 222
 223 /*
 224  * 1. Next Verifier
 225  */
 226 /*ARGSUSED */
 227 static void
 228 authdes_nextverf (AUTH *auth)
 229 {
 230   /* what the heck am I supposed to do??? */
 231 }
 232
 233
 234
 235 /*
 236  * 2. Marshal
 237  */
 238 static bool_t
 239 authdes_marshal (AUTH *auth, XDR *xdrs)
 240 {
 241   struct ad_private *ad = AUTH_PRIVATE (auth);
 242   struct authdes_cred *cred = &ad->ad_cred;
 243   struct authdes_verf *verf = &ad->ad_verf;
 244   des_block cryptbuf[2];
 245   des_block ivec;
 246   int status;
 247   int len;
 248   register int32_t *ixdr;
 249   struct timeval tval;
 250
 251   /*
 252    * Figure out the "time", accounting for any time difference
 253    * with the server if necessary.
 254    */
 255   __gettimeofday (&tval, (struct timezone *) NULL);
 256   ad->ad_timestamp.tv_sec = tval.tv_sec + ad->ad_timediff.tv_sec;
 257   ad->ad_timestamp.tv_usec = tval.tv_usec + ad->ad_timediff.tv_usec;
 258   if (ad->ad_timestamp.tv_usec >= MILLION)
 259     {
 260       ad->ad_timestamp.tv_usec -= MILLION;
 261       ad->ad_timestamp.tv_sec += 1;
 262     }
 263
 264   /*
 265    * XDR the timestamp and possibly some other things, then
 266    * encrypt them.
 267    * XXX We have a real Year 2038 problem here.
 268    */
 269   ixdr = (int32_t *) cryptbuf;
 270   IXDR_PUT_INT32 (ixdr, ad->ad_timestamp.tv_sec);
 271   IXDR_PUT_INT32 (ixdr, ad->ad_timestamp.tv_usec);
 272   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 273     {
 274       IXDR_PUT_U_INT32 (ixdr, ad->ad_window);
 275       IXDR_PUT_U_INT32 (ixdr, ad->ad_window - 1);
 276       ivec.key.high = ivec.key.low = 0;
 277       status = cbc_crypt ((char *) &auth->ah_key, (char *) cryptbuf,
 278               2 * sizeof (des_block), DES_ENCRYPT | DES_HW, (char *) &ivec);
 279     }
 280   else
 281     status = ecb_crypt ((char *) &auth->ah_key, (char *) cryptbuf,
 282                         sizeof (des_block), DES_ENCRYPT | DES_HW);
 283
 284   if (DES_FAILED (status))
 285     {
 286       debug ("authdes_marshal: DES encryption failure");
 287       return FALSE;
 288     }
 289   ad->ad_verf.adv_xtimestamp = cryptbuf[0];
 290   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 291     {
 292       ad->ad_cred.adc_fullname.window = cryptbuf[1].key.high;
 293       ad->ad_verf.adv_winverf = cryptbuf[1].key.low;
 294     }
 295   else
 296     {
 297       ad->ad_cred.adc_nickname = ad->ad_nickname;
 298       ad->ad_verf.adv_winverf = 0;
 299     }
 300
 301   /*
 302    * Serialize the credential and verifier into opaque
 303    * authentication data.
 304    */
 305   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 306     len = ((1 + 1 + 2 + 1) * BYTES_PER_XDR_UNIT + ad->ad_fullnamelen);
 307   else
 308     len = (1 + 1) * BYTES_PER_XDR_UNIT;
 309
 310   if ((ixdr = xdr_inline (xdrs, 2 * BYTES_PER_XDR_UNIT)) != NULL)
 311     {
 312       IXDR_PUT_INT32 (ixdr, AUTH_DES);
 313       IXDR_PUT_U_INT32 (ixdr, len);
 314     }
 315   else
 316     {
 317       ATTEMPT (xdr_putint32 (xdrs, &auth->ah_cred.oa_flavor));
 318       ATTEMPT (xdr_putint32 (xdrs, &len));
 319     }
 320   ATTEMPT (xdr_authdes_cred (xdrs, cred));
 321
 322   len = (2 + 1) * BYTES_PER_XDR_UNIT;
 323   if ((ixdr = xdr_inline (xdrs, 2 * BYTES_PER_XDR_UNIT)) != NULL)
 324     {
 325       IXDR_PUT_INT32 (ixdr, AUTH_DES);
 326       IXDR_PUT_U_INT32 (ixdr, len);
 327     }
 328   else
 329     {
 330       ATTEMPT (xdr_putint32 (xdrs, &auth->ah_verf.oa_flavor));
 331       ATTEMPT (xdr_putint32 (xdrs, &len));
 332     }
 333   ATTEMPT (xdr_authdes_verf (xdrs, verf));
 334
 335   return TRUE;
 336 }
 337
 338
 339 /*
 340  * 3. Validate
 341  */
 342 static bool_t
 343 authdes_validate (AUTH *auth, struct opaque_auth *rverf)
 344 {
 345   struct ad_private *ad = AUTH_PRIVATE (auth);
 346   struct authdes_verf verf;
 347   int status;
 348   register uint32_t *ixdr;
 349
 350   if (rverf->oa_length != (2 + 1) * BYTES_PER_XDR_UNIT)
 351     return FALSE;
 352
 353   ixdr = (uint32_t *) rverf->oa_base;
 354   verf.adv_xtimestamp.key.high = *ixdr++;
 355   verf.adv_xtimestamp.key.low = *ixdr++;
 356   verf.adv_int_u = *ixdr++;     /* nickname not XDR'd ! */
 357
 358   /*
 359    * Decrypt the timestamp
 360    */
 361   status = ecb_crypt ((char *) &auth->ah_key, (char *) &verf.adv_xtimestamp,
 362                       sizeof (des_block), DES_DECRYPT | DES_HW);
 363
 364   if (DES_FAILED (status))
 365     {
 366       debug ("authdes_validate: DES decryption failure");
 367       return FALSE;
 368     }
 369
 370   /*
 371    * xdr the decrypted timestamp
 372    */
 373   ixdr = (uint32_t *) verf.adv_xtimestamp.c;
 374   verf.adv_timestamp.tv_sec = IXDR_GET_U_INT32 (ixdr) + 1;
 375   verf.adv_timestamp.tv_usec = IXDR_GET_U_INT32 (ixdr);
 376
 377   /*
 378    * validate
 379    */
 380   if (memcmp ((char *) &ad->ad_timestamp, (char *) &verf.adv_timestamp,
 381               sizeof (struct rpc_timeval)) != 0)
 382     {
 383       debug ("authdes_validate: verifier mismatch\n");
 384       return FALSE;
 385     }
 386
 387   /*
 388    * We have a nickname now, let's use it
 389    */
 390   ad->ad_nickname = verf.adv_nickname;
 391   ad->ad_cred.adc_namekind = ADN_NICKNAME;
 392   return TRUE;
 393 }
 394
 395 /*
 396  * 4. Refresh
 397  */
 398 static bool_t
 399 authdes_refresh (AUTH *auth)
 400 {
 401   netobj pkey;
 402   struct ad_private *ad = AUTH_PRIVATE (auth);
 403   struct authdes_cred *cred = &ad->ad_cred;
 404
 405   if (ad->ad_dosync && !synchronize (&ad->ad_syncaddr, &ad->ad_timediff))
 406     {
 407       /*
 408        * Hope the clocks are synced!
 409        */
 410       ad->ad_timediff.tv_sec = ad->ad_timediff.tv_usec = 0;
 411       debug ("authdes_refresh: unable to synchronize with server");
 412     }
 413   ad->ad_xkey = auth->ah_key;
 414   pkey.n_bytes = (char *) (ad->ad_pkey);
 415   pkey.n_len = strlen ((char *) ad->ad_pkey) + 1;
 416   if (key_encryptsession_pk (ad->ad_servername, &pkey, &ad->ad_xkey) < 0)
 417     {
 418       debug ("authdes_create: unable to encrypt conversation key");
 419       return FALSE;
 420     }
 421   cred->adc_fullname.key = ad->ad_xkey;
 422   cred->adc_namekind = ADN_FULLNAME;
 423   cred->adc_fullname.name = ad->ad_fullname;
 424   return TRUE;
 425 }
 426
 427 /*
 428  * 5. Destroy
 429  */
 430 static void
 431 authdes_destroy (AUTH *auth)
 432 {
 433   struct ad_private *ad = AUTH_PRIVATE (auth);
 434
 435   FREE (ad->ad_fullname, ad->ad_fullnamelen + 1);
 436   FREE (ad->ad_servername, ad->ad_servernamelen + 1);
 437   FREE (ad, sizeof (struct ad_private));
 438   FREE (auth, sizeof (AUTH));
 439 }
 440
 441 /*
 442  * Synchronize with the server at the given address, that is,
 443  * adjust timep to reflect the delta between our clocks
 444  */
 445 static bool_t
 446 internal_function
 447 synchronize (struct sockaddr *syncaddr, struct rpc_timeval *timep)
 448 {
 449   struct timeval mytime;
 450   struct rpc_timeval timeout;
 451
 452   timeout.tv_sec = RTIME_TIMEOUT;
 453   timeout.tv_usec = 0;
 454   if (rtime ((struct sockaddr_in *) syncaddr, timep, &timeout) < 0)
 455     return FALSE;
 456
 457   __gettimeofday (&mytime, (struct timezone *) NULL);
 458   timep->tv_sec -= mytime.tv_sec;
 459   if (mytime.tv_usec > timep->tv_usec)
 460     {
 461       timep->tv_sec -= 1;
 462       timep->tv_usec += MILLION;
 463     }
 464   timep->tv_usec -= mytime.tv_usec;
 465   return TRUE;
 466 }