sunrpc/xdr.c

   1 /*
   2  * xdr.c, Generic XDR routines implementation.
   3  *
   4  * Copyright (c) 2010, Oracle America, Inc.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions are
   8  * met:
   9  *
  10  *     * Redistributions of source code must retain the above copyright
  11  *       notice, this list of conditions and the following disclaimer.
  12  *     * Redistributions in binary form must reproduce the above
  13  *       copyright notice, this list of conditions and the following
  14  *       disclaimer in the documentation and/or other materials
  15  *       provided with the distribution.
  16  *     * Neither the name of the "Oracle America, Inc." nor the names of its
  17  *       contributors may be used to endorse or promote products derived
  18  *       from this software without specific prior written permission.
  19  *
  20  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  23  *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  24  *   COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
  25  *   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  *   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  27  *   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  28  *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  29  *   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  30  *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  *
  33  * These are the "generic" xdr routines used to serialize and de-serialize
  34  * most common data items.  See xdr.h for more info on the interface to
  35  * xdr.
  36  */
  37
  38 #include <stdio.h>
  39 #include <limits.h>
  40 #include <string.h>
  41 #include <libintl.h>
  42 #include <wchar.h>
  43 #include <stdint.h>
  44
  45 #include <rpc/types.h>
  46 #include <rpc/xdr.h>
  47
  48
  49 /*
  50  * constants specific to the xdr "protocol"
  51  */
  52 #define XDR_FALSE       ((long) 0)
  53 #define XDR_TRUE        ((long) 1)
  54 #define LASTUNSIGNED    ((u_int) 0-1)
  55
  56 /*
  57  * for unit alignment
  58  */
  59 static const char xdr_zero[BYTES_PER_XDR_UNIT] = {0, 0, 0, 0};
  60
  61 /*
  62  * Free a data structure using XDR
  63  * Not a filter, but a convenient utility nonetheless
  64  */
  65 void
  66 xdr_free (xdrproc_t proc, char *objp)
  67 {
  68   XDR x;
  69
  70   x.x_op = XDR_FREE;
  71   (*proc) (&x, objp);
  72 }
  73 #ifdef EXPORT_RPC_SYMBOLS
  74 libc_hidden_def (xdr_free)
  75 #else
  76 libc_hidden_nolink_sunrpc (xdr_free, GLIBC_2_0)
  77 #endif
  78
  79 /*
  80  * XDR nothing
  81  */
  82 bool_t
  83 xdr_void (void)
  84 {
  85   return TRUE;
  86 }
  87 #ifdef EXPORT_RPC_SYMBOLS
  88 libc_hidden_def (xdr_void)
  89 #else
  90 libc_hidden_nolink_sunrpc (xdr_void, GLIBC_2_0)
  91 #endif
  92
  93 /*
  94  * XDR integers
  95  */
  96 bool_t
  97 xdr_int (XDR *xdrs, int *ip)
  98 {
  99
 100 #if INT_MAX < LONG_MAX
 101   long l;
 102
 103   switch (xdrs->x_op)
 104     {
 105     case XDR_ENCODE:
 106       l = (long) *ip;
 107       return XDR_PUTLONG (xdrs, &l);
 108
 109     case XDR_DECODE:
 110       if (!XDR_GETLONG (xdrs, &l))
 111         {
 112           return FALSE;
 113         }
 114       *ip = (int) l;
 115     case XDR_FREE:
 116       return TRUE;
 117     }
 118   return FALSE;
 119 #elif INT_MAX == LONG_MAX
 120   return xdr_long (xdrs, (long *) ip);
 121 #elif INT_MAX == SHRT_MAX
 122   return xdr_short (xdrs, (short *) ip);
 123 #else
 124 #error unexpected integer sizes in_xdr_int()
 125 #endif
 126 }
 127 #ifdef EXPORT_RPC_SYMBOLS
 128 libc_hidden_def (xdr_int)
 129 #else
 130 libc_hidden_nolink_sunrpc (xdr_int, GLIBC_2_0)
 131 #endif
 132
 133 /*
 134  * XDR unsigned integers
 135  */
 136 bool_t
 137 xdr_u_int (XDR *xdrs, u_int *up)
 138 {
 139 #if UINT_MAX < ULONG_MAX
 140   long l;
 141
 142   switch (xdrs->x_op)
 143     {
 144     case XDR_ENCODE:
 145       l = (u_long) * up;
 146       return XDR_PUTLONG (xdrs, &l);
 147
 148     case XDR_DECODE:
 149       if (!XDR_GETLONG (xdrs, &l))
 150         {
 151           return FALSE;
 152         }
 153       *up = (u_int) (u_long) l;
 154     case XDR_FREE:
 155       return TRUE;
 156     }
 157   return FALSE;
 158 #elif UINT_MAX == ULONG_MAX
 159   return xdr_u_long (xdrs, (u_long *) up);
 160 #elif UINT_MAX == USHRT_MAX
 161   return xdr_short (xdrs, (short *) up);
 162 #else
 163 #error unexpected integer sizes in_xdr_u_int()
 164 #endif
 165 }
 166 #ifdef EXPORT_RPC_SYMBOLS
 167 libc_hidden_def (xdr_u_int)
 168 #else
 169 libc_hidden_nolink_sunrpc (xdr_u_int, GLIBC_2_0)
 170 #endif
 171
 172 /*
 173  * XDR long integers
 174  * The definition of xdr_long() is kept for backward
 175  * compatibility. Instead xdr_int() should be used.
 176  */
 177 bool_t
 178 xdr_long (XDR *xdrs, long *lp)
 179 {
 180
 181   if (xdrs->x_op == XDR_ENCODE
 182       && (sizeof (int32_t) == sizeof (long)
 183           || (int32_t) *lp == *lp))
 184     return XDR_PUTLONG (xdrs, lp);
 185
 186   if (xdrs->x_op == XDR_DECODE)
 187     return XDR_GETLONG (xdrs, lp);
 188
 189   if (xdrs->x_op == XDR_FREE)
 190     return TRUE;
 191
 192   return FALSE;
 193 }
 194 #ifdef EXPORT_RPC_SYMBOLS
 195 libc_hidden_def (xdr_long)
 196 #else
 197 libc_hidden_nolink_sunrpc (xdr_long, GLIBC_2_0)
 198 #endif
 199
 200 /*
 201  * XDR unsigned long integers
 202  * The definition of xdr_u_long() is kept for backward
 203  * compatibility. Instead xdr_u_int() should be used.
 204  */
 205 bool_t
 206 xdr_u_long (XDR *xdrs, u_long *ulp)
 207 {
 208   switch (xdrs->x_op)
 209     {
 210     case XDR_DECODE:
 211       {
 212         long int tmp;
 213
 214         if (XDR_GETLONG (xdrs, &tmp) == FALSE)
 215           return FALSE;
 216
 217         *ulp = (uint32_t) tmp;
 218         return TRUE;
 219       }
 220
 221     case XDR_ENCODE:
 222       if (sizeof (uint32_t) != sizeof (u_long)
 223           && (uint32_t) *ulp != *ulp)
 224         return FALSE;
 225
 226       return XDR_PUTLONG (xdrs, (long *) ulp);
 227
 228     case XDR_FREE:
 229       return TRUE;
 230     }
 231   return FALSE;
 232 }
 233 #ifdef EXPORT_RPC_SYMBOLS
 234 libc_hidden_def (xdr_u_long)
 235 #else
 236 libc_hidden_nolink_sunrpc (xdr_u_long, GLIBC_2_0)
 237 #endif
 238
 239 /*
 240  * XDR hyper integers
 241  * same as xdr_u_hyper - open coded to save a proc call!
 242  */
 243 bool_t
 244 xdr_hyper (XDR *xdrs, quad_t *llp)
 245 {
 246   long int t1, t2;
 247
 248   if (xdrs->x_op == XDR_ENCODE)
 249     {
 250       t1 = (long) ((*llp) >> 32);
 251       t2 = (long) (*llp);
 252       return (XDR_PUTLONG(xdrs, &t1) && XDR_PUTLONG(xdrs, &t2));
 253     }
 254
 255   if (xdrs->x_op == XDR_DECODE)
 256     {
 257       if (!XDR_GETLONG(xdrs, &t1) || !XDR_GETLONG(xdrs, &t2))
 258         return FALSE;
 259       *llp = ((quad_t) t1) << 32;
 260       *llp |= (uint32_t) t2;
 261       return TRUE;
 262     }
 263
 264   if (xdrs->x_op == XDR_FREE)
 265     return TRUE;
 266
 267   return FALSE;
 268 }
 269 #ifdef EXPORT_RPC_SYMBOLS
 270 libc_hidden_def (xdr_hyper)
 271 #else
 272 libc_hidden_nolink_sunrpc (xdr_hyper, GLIBC_2_1_1)
 273 #endif
 274
 275 /*
 276  * XDR hyper integers
 277  * same as xdr_hyper - open coded to save a proc call!
 278  */
 279 bool_t
 280 xdr_u_hyper (XDR *xdrs, u_quad_t *ullp)
 281 {
 282   long int t1, t2;
 283
 284   if (xdrs->x_op == XDR_ENCODE)
 285     {
 286       t1 = (unsigned long) ((*ullp) >> 32);
 287       t2 = (unsigned long) (*ullp);
 288       return (XDR_PUTLONG(xdrs, &t1) && XDR_PUTLONG(xdrs, &t2));
 289     }
 290
 291   if (xdrs->x_op == XDR_DECODE)
 292     {
 293       if (!XDR_GETLONG(xdrs, &t1) || !XDR_GETLONG(xdrs, &t2))
 294         return FALSE;
 295       *ullp = ((u_quad_t) t1) << 32;
 296       *ullp |= (uint32_t) t2;
 297       return TRUE;
 298     }
 299
 300   if (xdrs->x_op == XDR_FREE)
 301     return TRUE;
 302
 303   return FALSE;
 304 }
 305 #ifdef EXPORT_RPC_SYMBOLS
 306 libc_hidden_def (xdr_u_hyper)
 307 #else
 308 libc_hidden_nolink_sunrpc (xdr_u_hyper, GLIBC_2_1_1)
 309 #endif
 310
 311 bool_t
 312 xdr_longlong_t (XDR *xdrs, quad_t *llp)
 313 {
 314   return xdr_hyper (xdrs, llp);
 315 }
 316 #ifdef EXPORT_RPC_SYMBOLS
 317 libc_hidden_def (xdr_longlong_t)
 318 #else
 319 libc_hidden_nolink_sunrpc (xdr_longlong_t, GLIBC_2_1_1)
 320 #endif
 321
 322 bool_t
 323 xdr_u_longlong_t (XDR *xdrs, u_quad_t *ullp)
 324 {
 325   return xdr_u_hyper (xdrs, ullp);
 326 }
 327 #ifdef EXPORT_RPC_SYMBOLS
 328 libc_hidden_def (xdr_u_longlong_t)
 329 #else
 330 libc_hidden_nolink_sunrpc (xdr_u_longlong_t, GLIBC_2_1_1)
 331 #endif
 332
 333 /*
 334  * XDR short integers
 335  */
 336 bool_t
 337 xdr_short (XDR *xdrs, short *sp)
 338 {
 339   long l;
 340
 341   switch (xdrs->x_op)
 342     {
 343     case XDR_ENCODE:
 344       l = (long) *sp;
 345       return XDR_PUTLONG (xdrs, &l);
 346
 347     case XDR_DECODE:
 348       if (!XDR_GETLONG (xdrs, &l))
 349         {
 350           return FALSE;
 351         }
 352       *sp = (short) l;
 353       return TRUE;
 354
 355     case XDR_FREE:
 356       return TRUE;
 357     }
 358   return FALSE;
 359 }
 360 #ifdef EXPORT_RPC_SYMBOLS
 361 libc_hidden_def (xdr_short)
 362 #else
 363 libc_hidden_nolink_sunrpc (xdr_short, GLIBC_2_0)
 364 #endif
 365
 366 /*
 367  * XDR unsigned short integers
 368  */
 369 bool_t
 370 xdr_u_short (XDR *xdrs, u_short *usp)
 371 {
 372   long l;
 373
 374   switch (xdrs->x_op)
 375     {
 376     case XDR_ENCODE:
 377       l = (u_long) * usp;
 378       return XDR_PUTLONG (xdrs, &l);
 379
 380     case XDR_DECODE:
 381       if (!XDR_GETLONG (xdrs, &l))
 382         {
 383           return FALSE;
 384         }
 385       *usp = (u_short) (u_long) l;
 386       return TRUE;
 387
 388     case XDR_FREE:
 389       return TRUE;
 390     }
 391   return FALSE;
 392 }
 393 #ifdef EXPORT_RPC_SYMBOLS
 394 libc_hidden_def (xdr_u_short)
 395 #else
 396 libc_hidden_nolink_sunrpc (xdr_u_short, GLIBC_2_0)
 397 #endif
 398
 399
 400 /*
 401  * XDR a char
 402  */
 403 bool_t
 404 xdr_char (XDR *xdrs, char *cp)
 405 {
 406   int i;
 407
 408   i = (*cp);
 409   if (!xdr_int (xdrs, &i))
 410     {
 411       return FALSE;
 412     }
 413   *cp = i;
 414   return TRUE;
 415 }
 416 #ifdef EXPORT_RPC_SYMBOLS
 417 libc_hidden_def (xdr_char)
 418 #else
 419 libc_hidden_nolink_sunrpc (xdr_char, GLIBC_2_0)
 420 #endif
 421
 422 /*
 423  * XDR an unsigned char
 424  */
 425 bool_t
 426 xdr_u_char (XDR *xdrs, u_char *cp)
 427 {
 428   u_int u;
 429
 430   u = (*cp);
 431   if (!xdr_u_int (xdrs, &u))
 432     {
 433       return FALSE;
 434     }
 435   *cp = u;
 436   return TRUE;
 437 }
 438 #ifdef EXPORT_RPC_SYMBOLS
 439 libc_hidden_def (xdr_u_char)
 440 #else
 441 libc_hidden_nolink_sunrpc (xdr_u_char, GLIBC_2_0)
 442 #endif
 443
 444 /*
 445  * XDR booleans
 446  */
 447 bool_t
 448 xdr_bool (XDR *xdrs, bool_t *bp)
 449 {
 450   long lb;
 451
 452   switch (xdrs->x_op)
 453     {
 454     case XDR_ENCODE:
 455       lb = *bp ? XDR_TRUE : XDR_FALSE;
 456       return XDR_PUTLONG (xdrs, &lb);
 457
 458     case XDR_DECODE:
 459       if (!XDR_GETLONG (xdrs, &lb))
 460         {
 461           return FALSE;
 462         }
 463       *bp = (lb == XDR_FALSE) ? FALSE : TRUE;
 464       return TRUE;
 465
 466     case XDR_FREE:
 467       return TRUE;
 468     }
 469   return FALSE;
 470 }
 471 #ifdef EXPORT_RPC_SYMBOLS
 472 libc_hidden_def (xdr_bool)
 473 #else
 474 libc_hidden_nolink_sunrpc (xdr_bool, GLIBC_2_0)
 475 #endif
 476
 477 /*
 478  * XDR enumerations
 479  */
 480 bool_t
 481 xdr_enum (XDR *xdrs, enum_t *ep)
 482 {
 483   enum sizecheck
 484     {
 485       SIZEVAL
 486     };                          /* used to find the size of an enum */
 487
 488   /*
 489    * enums are treated as ints
 490    */
 491   if (sizeof (enum sizecheck) == 4)
 492     {
 493 #if INT_MAX < LONG_MAX
 494       long l;
 495
 496       switch (xdrs->x_op)
 497         {
 498         case XDR_ENCODE:
 499           l = *ep;
 500           return XDR_PUTLONG (xdrs, &l);
 501
 502         case XDR_DECODE:
 503           if (!XDR_GETLONG (xdrs, &l))
 504             {
 505               return FALSE;
 506             }
 507           *ep = l;
 508         case XDR_FREE:
 509           return TRUE;
 510
 511         }
 512       return FALSE;
 513 #else
 514       return xdr_long (xdrs, (long *) ep);
 515 #endif
 516     }
 517   else if (sizeof (enum sizecheck) == sizeof (short))
 518     {
 519       return xdr_short (xdrs, (short *) ep);
 520     }
 521   else
 522     {
 523       return FALSE;
 524     }
 525 }
 526 #ifdef EXPORT_RPC_SYMBOLS
 527 libc_hidden_def (xdr_enum)
 528 #else
 529 libc_hidden_nolink_sunrpc (xdr_enum, GLIBC_2_0)
 530 #endif
 531
 532 /*
 533  * XDR opaque data
 534  * Allows the specification of a fixed size sequence of opaque bytes.
 535  * cp points to the opaque object and cnt gives the byte length.
 536  */
 537 bool_t
 538 xdr_opaque (XDR *xdrs, caddr_t cp, u_int cnt)
 539 {
 540   u_int rndup;
 541   static char crud[BYTES_PER_XDR_UNIT];
 542
 543   /*
 544    * if no data we are done
 545    */
 546   if (cnt == 0)
 547     return TRUE;
 548
 549   /*
 550    * round byte count to full xdr units
 551    */
 552   rndup = cnt % BYTES_PER_XDR_UNIT;
 553   if (rndup > 0)
 554     rndup = BYTES_PER_XDR_UNIT - rndup;
 555
 556   switch (xdrs->x_op)
 557     {
 558     case XDR_DECODE:
 559       if (!XDR_GETBYTES (xdrs, cp, cnt))
 560         {
 561           return FALSE;
 562         }
 563       if (rndup == 0)
 564         return TRUE;
 565       return XDR_GETBYTES (xdrs, (caddr_t)crud, rndup);
 566
 567     case XDR_ENCODE:
 568       if (!XDR_PUTBYTES (xdrs, cp, cnt))
 569         {
 570           return FALSE;
 571         }
 572       if (rndup == 0)
 573         return TRUE;
 574       return XDR_PUTBYTES (xdrs, xdr_zero, rndup);
 575
 576     case XDR_FREE:
 577       return TRUE;
 578     }
 579   return FALSE;
 580 }
 581 #ifdef EXPORT_RPC_SYMBOLS
 582 libc_hidden_def (xdr_opaque)
 583 #else
 584 libc_hidden_nolink_sunrpc (xdr_opaque, GLIBC_2_0)
 585 #endif
 586
 587 /*
 588  * XDR counted bytes
 589  * *cpp is a pointer to the bytes, *sizep is the count.
 590  * If *cpp is NULL maxsize bytes are allocated
 591  */
 592 bool_t
 593 xdr_bytes (XDR *xdrs, char **cpp, u_int *sizep, u_int maxsize)
 594 {
 595   char *sp = *cpp;      /* sp is the actual string pointer */
 596   u_int nodesize;
 597
 598   /*
 599    * first deal with the length since xdr bytes are counted
 600    */
 601   if (!xdr_u_int (xdrs, sizep))
 602     {
 603       return FALSE;
 604     }
 605   nodesize = *sizep;
 606   if ((nodesize > maxsize) && (xdrs->x_op != XDR_FREE))
 607     {
 608       return FALSE;
 609     }
 610
 611   /*
 612    * now deal with the actual bytes
 613    */
 614   switch (xdrs->x_op)
 615     {
 616     case XDR_DECODE:
 617       if (nodesize == 0)
 618         {
 619           return TRUE;
 620         }
 621       if (sp == NULL)
 622         {
 623           *cpp = sp = (char *) mem_alloc (nodesize);
 624         }
 625       if (sp == NULL)
 626         {
 627           (void) __fxprintf (NULL, "%s: %s", __func__, _("out of memory\n"));
 628           return FALSE;
 629         }
 630       /* fall into ... */
 631
 632     case XDR_ENCODE:
 633       return xdr_opaque (xdrs, sp, nodesize);
 634
 635     case XDR_FREE:
 636       if (sp != NULL)
 637         {
 638           mem_free (sp, nodesize);
 639           *cpp = NULL;
 640         }
 641       return TRUE;
 642     }
 643   return FALSE;
 644 }
 645 #ifdef EXPORT_RPC_SYMBOLS
 646 libc_hidden_def (xdr_bytes)
 647 #else
 648 libc_hidden_nolink_sunrpc (xdr_bytes, GLIBC_2_0)
 649 #endif
 650
 651 /*
 652  * Implemented here due to commonality of the object.
 653  */
 654 bool_t
 655 xdr_netobj (XDR *xdrs, struct netobj *np)
 656 {
 657
 658   return xdr_bytes (xdrs, &np->n_bytes, &np->n_len, MAX_NETOBJ_SZ);
 659 }
 660 #ifdef EXPORT_RPC_SYMBOLS
 661 libc_hidden_def (xdr_netobj)
 662 #else
 663 libc_hidden_nolink_sunrpc (xdr_netobj, GLIBC_2_0)
 664 #endif
 665
 666 /*
 667  * XDR a discriminated union
 668  * Support routine for discriminated unions.
 669  * You create an array of xdrdiscrim structures, terminated with
 670  * an entry with a null procedure pointer.  The routine gets
 671  * the discriminant value and then searches the array of xdrdiscrims
 672  * looking for that value.  It calls the procedure given in the xdrdiscrim
 673  * to handle the discriminant.  If there is no specific routine a default
 674  * routine may be called.
 675  * If there is no specific or default routine an error is returned.
 676  */
 677 bool_t
 678 xdr_union (xdrs, dscmp, unp, choices, dfault)
 679      XDR *xdrs;
 680      enum_t *dscmp;             /* enum to decide which arm to work on */
 681      char *unp;                 /* the union itself */
 682      const struct xdr_discrim *choices; /* [value, xdr proc] for each arm */
 683      xdrproc_t dfault;          /* default xdr routine */
 684 {
 685   enum_t dscm;
 686
 687   /*
 688    * we deal with the discriminator;  it's an enum
 689    */
 690   if (!xdr_enum (xdrs, dscmp))
 691     {
 692       return FALSE;
 693     }
 694   dscm = *dscmp;
 695
 696   /*
 697    * search choices for a value that matches the discriminator.
 698    * if we find one, execute the xdr routine for that value.
 699    */
 700   for (; choices->proc != NULL_xdrproc_t; choices++)
 701     {
 702       if (choices->value == dscm)
 703         return (*(choices->proc)) (xdrs, unp, LASTUNSIGNED);
 704     }
 705
 706   /*
 707    * no match - execute the default xdr routine if there is one
 708    */
 709   return ((dfault == NULL_xdrproc_t) ? FALSE :
 710           (*dfault) (xdrs, unp, LASTUNSIGNED));
 711 }
 712 libc_hidden_nolink_sunrpc (xdr_union, GLIBC_2_0)
 713
 714
 715 /*
 716  * Non-portable xdr primitives.
 717  * Care should be taken when moving these routines to new architectures.
 718  */
 719
 720
 721 /*
 722  * XDR null terminated ASCII strings
 723  * xdr_string deals with "C strings" - arrays of bytes that are
 724  * terminated by a NULL character.  The parameter cpp references a
 725  * pointer to storage; If the pointer is null, then the necessary
 726  * storage is allocated.  The last parameter is the max allowed length
 727  * of the string as specified by a protocol.
 728  */
 729 bool_t
 730 xdr_string (XDR *xdrs, char **cpp, u_int maxsize)
 731 {
 732   char *sp = *cpp;      /* sp is the actual string pointer */
 733   /* Initialize to silence the compiler.  It is not really needed because SIZE
 734      never actually gets used without being initialized.  */
 735   u_int size = 0;
 736   u_int nodesize;
 737
 738   /*
 739    * first deal with the length since xdr strings are counted-strings
 740    */
 741   switch (xdrs->x_op)
 742     {
 743     case XDR_FREE:
 744       if (sp == NULL)
 745         {
 746           return TRUE;          /* already free */
 747         }
 748       /* fall through... */
 749     case XDR_ENCODE:
 750       if (sp == NULL)
 751         return FALSE;
 752       size = strlen (sp);
 753       break;
 754     case XDR_DECODE:
 755       break;
 756     }
 757   if (!xdr_u_int (xdrs, &size))
 758     {
 759       return FALSE;
 760     }
 761   if (size > maxsize)
 762     {
 763       return FALSE;
 764     }
 765   nodesize = size + 1;
 766   if (nodesize == 0)
 767     {
 768       /* This means an overflow.  It a bug in the caller which
 769          provided a too large maxsize but nevertheless catch it
 770          here.  */
 771       return FALSE;
 772     }
 773
 774   /*
 775    * now deal with the actual bytes
 776    */
 777   switch (xdrs->x_op)
 778     {
 779     case XDR_DECODE:
 780       if (sp == NULL)
 781         *cpp = sp = (char *) mem_alloc (nodesize);
 782       if (sp == NULL)
 783         {
 784           (void) __fxprintf (NULL, "%s: %s", __func__, _("out of memory\n"));
 785           return FALSE;
 786         }
 787       sp[size] = 0;
 788       /* fall into ... */
 789
 790     case XDR_ENCODE:
 791       return xdr_opaque (xdrs, sp, size);
 792
 793     case XDR_FREE:
 794       mem_free (sp, nodesize);
 795       *cpp = NULL;
 796       return TRUE;
 797     }
 798   return FALSE;
 799 }
 800 #ifdef EXPORT_RPC_SYMBOLS
 801 libc_hidden_def (xdr_string)
 802 #else
 803 libc_hidden_nolink_sunrpc (xdr_string, GLIBC_2_0)
 804 #endif
 805
 806 /*
 807  * Wrapper for xdr_string that can be called directly from
 808  * routines like clnt_call
 809  */
 810 bool_t
 811 xdr_wrapstring (XDR *xdrs, char **cpp)
 812 {
 813   if (xdr_string (xdrs, cpp, LASTUNSIGNED))
 814     {
 815       return TRUE;
 816     }
 817   return FALSE;
 818 }
 819 #ifdef EXPORT_RPC_SYMBOLS
 820 libc_hidden_def (xdr_wrapstring)
 821 #else
 822 libc_hidden_nolink_sunrpc (xdr_wrapstring, GLIBC_2_0)
 823 #endif