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 <rpc/des_crypt.h>
  37 #include <rpc/types.h>
  38 #include <rpc/auth.h>
  39 #include <rpc/auth_des.h>
  40 #include <rpc/xdr.h>
  41 #include <netinet/in.h>         /* XXX: just to get htonl() and ntohl() */
  42 #include <sys/socket.h>
  43
  44 #define MILLION         1000000L
  45 #define RTIME_TIMEOUT 5         /* seconds to wait for sync */
  46
  47 #define AUTH_PRIVATE(auth)      (struct ad_private *) auth->ah_private
  48 #define ALLOC(object_type)      (object_type *) mem_alloc(sizeof(object_type))
  49 #define FREE(ptr, size)         mem_free((char *)(ptr), (int) size)
  50 #define ATTEMPT(xdr_op)         if (!(xdr_op)) return (FALSE)
  51
  52 #define debug(msg)              /* printf("%s\n", msg) */
  53
  54
  55 /*
  56  * DES authenticator operations vector
  57  */
  58 static void authdes_nextverf (AUTH *);
  59 static bool_t authdes_marshal (AUTH *, XDR *);
  60 static bool_t authdes_validate (AUTH *, struct opaque_auth *);
  61 static bool_t authdes_refresh (AUTH *);
  62 static void authdes_destroy (AUTH *);
  63 static bool_t synchronize (struct sockaddr *, struct rpc_timeval *)
  64      internal_function;
  65
  66 static const struct auth_ops authdes_ops = {
  67   authdes_nextverf,
  68   authdes_marshal,
  69   authdes_validate,
  70   authdes_refresh,
  71   authdes_destroy
  72 };
  73
  74
  75 /*
  76  * This struct is pointed to by the ah_private field of an "AUTH *"
  77  */
  78 struct ad_private {
  79   char *ad_fullname;            /* client's full name */
  80   u_int ad_fullnamelen;         /* length of name, rounded up */
  81   char *ad_servername;          /* server's full name */
  82   u_int ad_servernamelen;       /* length of name, rounded up */
  83   uint32_t ad_window;           /* client specified window */
  84   bool_t ad_dosync;             /* synchronize? */
  85   struct sockaddr ad_syncaddr;  /* remote host to synch with */
  86   struct rpc_timeval ad_timediff;       /* server's time - client's time */
  87   uint32_t ad_nickname;         /* server's nickname for client */
  88   struct authdes_cred ad_cred;  /* storage for credential */
  89   struct authdes_verf ad_verf;  /* storage for verifier */
  90   struct rpc_timeval ad_timestamp;      /* timestamp sent */
  91   des_block ad_xkey;            /* encrypted conversation key */
  92   u_char ad_pkey[1024];         /* Servers actual public key */
  93 };
  94
  95
  96 /*
  97  * Create the client des authentication object
  98  */
  99 AUTH *
 100 authdes_create (const char *servername, u_int window,
 101                 struct sockaddr *syncaddr, des_block *ckey)
 102   /* servername - network name of server */
 103   /* window     - time to live */
 104   /* syncaddr   - optional addr of host to sync with */
 105   /* ckey       - optional conversation key to use */
 106 {
 107   char pkey_data[1024];
 108   netobj pkey;
 109
 110   if (!getpublickey (servername, pkey_data))
 111     return NULL;
 112
 113   pkey.n_bytes = pkey_data;
 114   pkey.n_len = strlen (pkey_data) + 1;
 115   return authdes_pk_create (servername, &pkey, window, syncaddr, ckey);
 116 }
 117 #ifdef EXPORT_RPC_SYMBOLS
 118 libc_hidden_def (authdes_create)
 119 #else
 120 libc_hidden_nolink (authdes_create, GLIBC_2_1)
 121 #endif
 122
 123 AUTH *
 124 authdes_pk_create (const char *servername, netobj *pkey, u_int window,
 125                    struct sockaddr *syncaddr, des_block *ckey)
 126 {
 127   AUTH *auth;
 128   struct ad_private *ad;
 129   char namebuf[MAXNETNAMELEN + 1];
 130
 131   /*
 132    * Allocate everything now
 133    */
 134   auth = ALLOC (AUTH);
 135   ad = ALLOC (struct ad_private);
 136
 137   if (auth == NULL || ad == NULL)
 138     {
 139       debug ("authdes_create: out of memory");
 140       goto failed;
 141     }
 142
 143   memset (ad, 0, sizeof (struct ad_private));
 144   memcpy (ad->ad_pkey, pkey->n_bytes, pkey->n_len);
 145   if (!getnetname (namebuf))
 146     goto failed;
 147   ad->ad_fullnamelen = RNDUP (strlen (namebuf));
 148   ad->ad_fullname = mem_alloc (ad->ad_fullnamelen + 1);
 149
 150   ad->ad_servernamelen = strlen (servername);
 151   ad->ad_servername = mem_alloc (ad->ad_servernamelen + 1);
 152
 153   if (ad->ad_fullname == NULL || ad->ad_servername == NULL)
 154     {
 155       debug ("authdes_create: out of memory");
 156       goto failed;
 157     }
 158
 159   /*
 160    * Set up private data
 161    */
 162   memcpy (ad->ad_fullname, namebuf, ad->ad_fullnamelen + 1);
 163   memcpy (ad->ad_servername, servername, ad->ad_servernamelen + 1);
 164   ad->ad_timediff.tv_sec = ad->ad_timediff.tv_usec = 0;
 165   if (syncaddr != NULL)
 166     {
 167       ad->ad_syncaddr = *syncaddr;
 168       ad->ad_dosync = TRUE;
 169     }
 170   else
 171     ad->ad_dosync = FALSE;
 172
 173   ad->ad_window = window;
 174   if (ckey == NULL)
 175     {
 176       if (key_gendes (&auth->ah_key) < 0)
 177         {
 178           debug ("authdes_create: unable to gen conversation key");
 179           goto failed;
 180         }
 181     }
 182   else
 183     auth->ah_key = *ckey;
 184
 185   /*
 186    * Set up auth handle
 187    */
 188   auth->ah_cred.oa_flavor = AUTH_DES;
 189   auth->ah_verf.oa_flavor = AUTH_DES;
 190   auth->ah_ops = (struct auth_ops *) &authdes_ops;
 191   auth->ah_private = (caddr_t) ad;
 192
 193   if (!authdes_refresh (auth))
 194     goto failed;
 195
 196   return auth;
 197
 198 failed:
 199   if (auth != NULL)
 200     FREE (auth, sizeof (AUTH));
 201   if (ad != NULL)
 202     {
 203       if (ad->ad_fullname != NULL)
 204         FREE (ad->ad_fullname, ad->ad_fullnamelen + 1);
 205       if (ad->ad_servername != NULL)
 206         FREE (ad->ad_servername, ad->ad_servernamelen + 1);
 207       FREE (ad, sizeof (struct ad_private));
 208     }
 209   return NULL;
 210 }
 211 #ifdef EXPORT_RPC_SYMBOLS
 212 libc_hidden_def (authdes_pk_create)
 213 #else
 214 libc_hidden_nolink (authdes_pk_create, GLIBC_2_1)
 215 #endif
 216
 217 /*
 218  * Implement the five authentication operations
 219  */
 220
 221
 222 /*
 223  * 1. Next Verifier
 224  */
 225 /*ARGSUSED */
 226 static void
 227 authdes_nextverf (AUTH *auth)
 228 {
 229   /* what the heck am I supposed to do??? */
 230 }
 231
 232
 233
 234 /*
 235  * 2. Marshal
 236  */
 237 static bool_t
 238 authdes_marshal (AUTH *auth, XDR *xdrs)
 239 {
 240   struct ad_private *ad = AUTH_PRIVATE (auth);
 241   struct authdes_cred *cred = &ad->ad_cred;
 242   struct authdes_verf *verf = &ad->ad_verf;
 243   des_block cryptbuf[2];
 244   des_block ivec;
 245   int status;
 246   int len;
 247   register int32_t *ixdr;
 248   struct timeval tval;
 249
 250   /*
 251    * Figure out the "time", accounting for any time difference
 252    * with the server if necessary.
 253    */
 254   __gettimeofday (&tval, (struct timezone *) NULL);
 255   ad->ad_timestamp.tv_sec = tval.tv_sec + ad->ad_timediff.tv_sec;
 256   ad->ad_timestamp.tv_usec = tval.tv_usec + ad->ad_timediff.tv_usec;
 257   if (ad->ad_timestamp.tv_usec >= MILLION)
 258     {
 259       ad->ad_timestamp.tv_usec -= MILLION;
 260       ad->ad_timestamp.tv_sec += 1;
 261     }
 262
 263   /*
 264    * XDR the timestamp and possibly some other things, then
 265    * encrypt them.
 266    * XXX We have a real Year 2038 problem here.
 267    */
 268   ixdr = (int32_t *) cryptbuf;
 269   IXDR_PUT_INT32 (ixdr, ad->ad_timestamp.tv_sec);
 270   IXDR_PUT_INT32 (ixdr, ad->ad_timestamp.tv_usec);
 271   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 272     {
 273       IXDR_PUT_U_INT32 (ixdr, ad->ad_window);
 274       IXDR_PUT_U_INT32 (ixdr, ad->ad_window - 1);
 275       ivec.key.high = ivec.key.low = 0;
 276       status = cbc_crypt ((char *) &auth->ah_key, (char *) cryptbuf,
 277               2 * sizeof (des_block), DES_ENCRYPT | DES_HW, (char *) &ivec);
 278     }
 279   else
 280     status = ecb_crypt ((char *) &auth->ah_key, (char *) cryptbuf,
 281                         sizeof (des_block), DES_ENCRYPT | DES_HW);
 282
 283   if (DES_FAILED (status))
 284     {
 285       debug ("authdes_marshal: DES encryption failure");
 286       return FALSE;
 287     }
 288   ad->ad_verf.adv_xtimestamp = cryptbuf[0];
 289   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 290     {
 291       ad->ad_cred.adc_fullname.window = cryptbuf[1].key.high;
 292       ad->ad_verf.adv_winverf = cryptbuf[1].key.low;
 293     }
 294   else
 295     {
 296       ad->ad_cred.adc_nickname = ad->ad_nickname;
 297       ad->ad_verf.adv_winverf = 0;
 298     }
 299
 300   /*
 301    * Serialize the credential and verifier into opaque
 302    * authentication data.
 303    */
 304   if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
 305     len = ((1 + 1 + 2 + 1) * BYTES_PER_XDR_UNIT + ad->ad_fullnamelen);
 306   else
 307     len = (1 + 1) * BYTES_PER_XDR_UNIT;
 308
 309   if ((ixdr = xdr_inline (xdrs, 2 * BYTES_PER_XDR_UNIT)) != NULL)
 310     {
 311       IXDR_PUT_INT32 (ixdr, AUTH_DES);
 312       IXDR_PUT_U_INT32 (ixdr, len);
 313     }
 314   else
 315     {
 316       ATTEMPT (xdr_putint32 (xdrs, &auth->ah_cred.oa_flavor));
 317       ATTEMPT (xdr_putint32 (xdrs, &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_INT32 (ixdr, AUTH_DES);
 325       IXDR_PUT_U_INT32 (ixdr, len);
 326     }
 327   else
 328     {
 329       ATTEMPT (xdr_putint32 (xdrs, &auth->ah_verf.oa_flavor));
 330       ATTEMPT (xdr_putint32 (xdrs, &len));
 331     }
 332   ATTEMPT (xdr_authdes_verf (xdrs, verf));
 333
 334   return TRUE;
 335 }
 336
 337
 338 /*
 339  * 3. Validate
 340  */
 341 static bool_t
 342 authdes_validate (AUTH *auth, struct opaque_auth *rverf)
 343 {
 344   struct ad_private *ad = AUTH_PRIVATE (auth);
 345   struct authdes_verf verf;
 346   int status;
 347   register uint32_t *ixdr;
 348
 349   if (rverf->oa_length != (2 + 1) * BYTES_PER_XDR_UNIT)
 350     return FALSE;
 351
 352   ixdr = (uint32_t *) rverf->oa_base;
 353   verf.adv_xtimestamp.key.high = *ixdr++;
 354   verf.adv_xtimestamp.key.low = *ixdr++;
 355   verf.adv_int_u = *ixdr++;     /* nickname not XDR'd ! */
 356
 357   /*
 358    * Decrypt the timestamp
 359    */
 360   status = ecb_crypt ((char *) &auth->ah_key, (char *) &verf.adv_xtimestamp,
 361                       sizeof (des_block), DES_DECRYPT | DES_HW);
 362
 363   if (DES_FAILED (status))
 364     {
 365       debug ("authdes_validate: DES decryption failure");
 366       return FALSE;
 367     }
 368
 369   /*
 370    * xdr the decrypted timestamp
 371    */
 372   ixdr = (uint32_t *) verf.adv_xtimestamp.c;
 373   verf.adv_timestamp.tv_sec = IXDR_GET_U_INT32 (ixdr) + 1;
 374   verf.adv_timestamp.tv_usec = IXDR_GET_U_INT32 (ixdr);
 375
 376   /*
 377    * validate
 378    */
 379   if (memcmp ((char *) &ad->ad_timestamp, (char *) &verf.adv_timestamp,
 380               sizeof (struct rpc_timeval)) != 0)
 381     {
 382       debug ("authdes_validate: verifier mismatch\n");
 383       return FALSE;
 384     }
 385
 386   /*
 387    * We have a nickname now, let's use it
 388    */
 389   ad->ad_nickname = verf.adv_nickname;
 390   ad->ad_cred.adc_namekind = ADN_NICKNAME;
 391   return TRUE;
 392 }
 393
 394 /*
 395  * 4. Refresh
 396  */
 397 static bool_t
 398 authdes_refresh (AUTH *auth)
 399 {
 400   netobj pkey;
 401   struct ad_private *ad = AUTH_PRIVATE (auth);
 402   struct authdes_cred *cred = &ad->ad_cred;
 403
 404   if (ad->ad_dosync && !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 rpc_timeval *timep)
 447 {
 448   struct timeval mytime;
 449   struct rpc_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 }