sunrpc/xdr.c

   1 /* @(#)xdr.c    2.1 88/07/29 4.0 RPCSRC */
   2 /*
   3  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
   4  * unrestricted use provided that this legend is included on all tape
   5  * media and as a part of the software program in whole or part.  Users
   6  * may copy or modify Sun RPC without charge, but are not authorized
   7  * to license or distribute it to anyone else except as part of a product or
   8  * program developed by the user.
   9  *
  10  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  11  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  12  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  13  *
  14  * Sun RPC is provided with no support and without any obligation on the
  15  * part of Sun Microsystems, Inc. to assist in its use, correction,
  16  * modification or enhancement.
  17  *
  18  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  19  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  20  * OR ANY PART THEREOF.
  21  *
  22  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  23  * or profits or other special, indirect and consequential damages, even if
  24  * Sun has been advised of the possibility of such damages.
  25  *
  26  * Sun Microsystems, Inc.
  27  * 2550 Garcia Avenue
  28  * Mountain View, California  94043
  29  */
  30 #if !defined(lint) && defined(SCCSIDS)
  31 static char sccsid[] = "@(#)xdr.c 1.35 87/08/12";
  32 #endif
  33
  34 /*
  35  * xdr.c, Generic XDR routines implementation.
  36  *
  37  * Copyright (C) 1986, Sun Microsystems, Inc.
  38  *
  39  * These are the "generic" xdr routines used to serialize and de-serialize
  40  * most common data items.  See xdr.h for more info on the interface to
  41  * xdr.
  42  */
  43
  44 #include <stdio.h>
  45 #include <limits.h>
  46 #include <string.h>
  47
  48 #include <rpc/types.h>
  49 #include <rpc/xdr.h>
  50
  51 /*
  52  * constants specific to the xdr "protocol"
  53  */
  54 #define XDR_FALSE       ((long) 0)
  55 #define XDR_TRUE        ((long) 1)
  56 #define LASTUNSIGNED    ((u_int) 0-1)
  57
  58 /*
  59  * for unit alignment
  60  */
  61 static const char xdr_zero[BYTES_PER_XDR_UNIT] = {0, 0, 0, 0};
  62
  63 /*
  64  * Free a data structure using XDR
  65  * Not a filter, but a convenient utility nonetheless
  66  */
  67 void
  68 xdr_free (xdrproc_t proc, char *objp)
  69 {
  70   XDR x;
  71
  72   x.x_op = XDR_FREE;
  73   (*proc) (&x, objp);
  74 }
  75
  76 /*
  77  * XDR nothing
  78  */
  79 bool_t
  80 xdr_void (void)
  81 {
  82   return TRUE;
  83 }
  84
  85 /*
  86  * XDR integers
  87  */
  88 bool_t
  89 xdr_int (XDR *xdrs, int *ip)
  90 {
  91
  92 #if INT_MAX < LONG_MAX
  93   long l;
  94
  95   switch (xdrs->x_op)
  96     {
  97     case XDR_ENCODE:
  98       l = (long) *ip;
  99       return XDR_PUTLONG (xdrs, &l);
 100
 101     case XDR_DECODE:
 102       if (!XDR_GETLONG (xdrs, &l))
 103         {
 104           return FALSE;
 105         }
 106       *ip = (int) l;
 107     case XDR_FREE:
 108       return TRUE;
 109     }
 110   return FALSE;
 111 #elif INT_MAX == LONG_MAX
 112   return xdr_long (xdrs, (long *) ip);
 113 #elif INT_MAX == SHRT_MAX
 114   return xdr_short (xdrs, (short *) ip);
 115 #else
 116 #error unexpected integer sizes in_xdr_int()
 117 #endif
 118 }
 119
 120 /*
 121  * XDR unsigned integers
 122  */
 123 bool_t
 124 xdr_u_int (XDR *xdrs, u_int *up)
 125 {
 126 #if UINT_MAX < ULONG_MAX
 127   u_long l;
 128
 129   switch (xdrs->x_op)
 130     {
 131     case XDR_ENCODE:
 132       l = (u_long) * up;
 133       return XDR_PUTLONG (xdrs, &l);
 134
 135     case XDR_DECODE:
 136       if (!XDR_GETLONG (xdrs, &l))
 137         {
 138           return FALSE;
 139         }
 140       *up = (u_int) l;
 141     case XDR_FREE:
 142       return TRUE;
 143     }
 144   return FALSE;
 145 #elif UINT_MAX == ULONG_MAX
 146   return xdr_u_long (xdrs, (u_long *) up);
 147 #elif UINT_MAX == USHRT_MAX
 148   return xdr_short (xdrs, (short *) up);
 149 #else
 150 #error unexpected integer sizes in_xdr_u_int()
 151 #endif
 152 }
 153
 154 /*
 155  * XDR 32bit integers
 156  */
 157 bool_t
 158 xdr_int32_t (XDR *xdrs, int32_t *lp)
 159 {
 160
 161   if (xdrs->x_op == XDR_ENCODE)
 162     return XDR_PUTINT32 (xdrs, lp);
 163
 164   if (xdrs->x_op == XDR_DECODE)
 165     return XDR_GETINT32 (xdrs, lp);
 166
 167   if (xdrs->x_op == XDR_FREE)
 168     return TRUE;
 169
 170   return FALSE;
 171 }
 172
 173 /*
 174  * XDR 32bit unsigned integers
 175  */
 176 bool_t
 177 xdr_uint32_t (XDR *xdrs, uint32_t *ulp)
 178 {
 179   switch (xdrs->x_op)
 180     {
 181     case XDR_DECODE:
 182       return XDR_GETINT32 (xdrs, (uint32_t *) ulp);
 183
 184     case XDR_ENCODE:
 185       return XDR_PUTINT32 (xdrs, (uint32_t *) ulp);
 186
 187     case XDR_FREE:
 188       return TRUE;
 189     }
 190   return FALSE;
 191 }
 192
 193 /*
 194  * XDR long integers
 195  * same as xdr_u_long - open coded to save a proc call!
 196  */
 197 bool_t
 198 xdr_long (XDR *xdrs, long *lp)
 199 {
 200
 201   if (xdrs->x_op == XDR_ENCODE)
 202     return XDR_PUTLONG (xdrs, lp);
 203
 204   if (xdrs->x_op == XDR_DECODE)
 205     return XDR_GETLONG (xdrs, lp);
 206
 207   if (xdrs->x_op == XDR_FREE)
 208     return TRUE;
 209
 210   return FALSE;
 211 }
 212
 213 /*
 214  * XDR unsigned long integers
 215  * same as xdr_long - open coded to save a proc call!
 216  */
 217 bool_t
 218 xdr_u_long (XDR *xdrs, u_long *ulp)
 219 {
 220   switch (xdrs->x_op)
 221     {
 222     case XDR_DECODE:
 223       return XDR_GETLONG (xdrs, (long *) ulp);
 224
 225     case XDR_ENCODE:
 226       return XDR_PUTLONG (xdrs, (long *) ulp);
 227
 228     case XDR_FREE:
 229       return TRUE;
 230     }
 231   return FALSE;
 232 }
 233
 234 /*
 235  * XDR short integers
 236  */
 237 bool_t
 238 xdr_short (xdrs, sp)
 239      XDR *xdrs;
 240      short *sp;
 241 {
 242   long l;
 243
 244   switch (xdrs->x_op)
 245     {
 246     case XDR_ENCODE:
 247       l = (long) *sp;
 248       return XDR_PUTLONG (xdrs, &l);
 249
 250     case XDR_DECODE:
 251       if (!XDR_GETLONG (xdrs, &l))
 252         {
 253           return FALSE;
 254         }
 255       *sp = (short) l;
 256       return TRUE;
 257
 258     case XDR_FREE:
 259       return TRUE;
 260     }
 261   return FALSE;
 262 }
 263
 264 /*
 265  * XDR unsigned short integers
 266  */
 267 bool_t
 268 xdr_u_short (xdrs, usp)
 269      XDR *xdrs;
 270      u_short *usp;
 271 {
 272   u_long l;
 273
 274   switch (xdrs->x_op)
 275     {
 276     case XDR_ENCODE:
 277       l = (u_long) * usp;
 278       return XDR_PUTLONG (xdrs, &l);
 279
 280     case XDR_DECODE:
 281       if (!XDR_GETLONG (xdrs, &l))
 282         {
 283           return FALSE;
 284         }
 285       *usp = (u_short) l;
 286       return TRUE;
 287
 288     case XDR_FREE:
 289       return TRUE;
 290     }
 291   return FALSE;
 292 }
 293
 294
 295 /*
 296  * XDR a char
 297  */
 298 bool_t
 299 xdr_char (xdrs, cp)
 300      XDR *xdrs;
 301      char *cp;
 302 {
 303   int i;
 304
 305   i = (*cp);
 306   if (!xdr_int (xdrs, &i))
 307     {
 308       return FALSE;
 309     }
 310   *cp = i;
 311   return TRUE;
 312 }
 313
 314 /*
 315  * XDR an unsigned char
 316  */
 317 bool_t
 318 xdr_u_char (xdrs, cp)
 319      XDR *xdrs;
 320      u_char *cp;
 321 {
 322   u_int u;
 323
 324   u = (*cp);
 325   if (!xdr_u_int (xdrs, &u))
 326     {
 327       return FALSE;
 328     }
 329   *cp = u;
 330   return TRUE;
 331 }
 332
 333 /*
 334  * XDR booleans
 335  */
 336 bool_t
 337 xdr_bool (xdrs, bp)
 338      XDR *xdrs;
 339      bool_t *bp;
 340 {
 341   long lb;
 342
 343   switch (xdrs->x_op)
 344     {
 345     case XDR_ENCODE:
 346       lb = *bp ? XDR_TRUE : XDR_FALSE;
 347       return XDR_PUTLONG (xdrs, &lb);
 348
 349     case XDR_DECODE:
 350       if (!XDR_GETLONG (xdrs, &lb))
 351         {
 352           return FALSE;
 353         }
 354       *bp = (lb == XDR_FALSE) ? FALSE : TRUE;
 355       return TRUE;
 356
 357     case XDR_FREE:
 358       return TRUE;
 359     }
 360   return FALSE;
 361 }
 362
 363 /*
 364  * XDR enumerations
 365  */
 366 bool_t
 367 xdr_enum (xdrs, ep)
 368      XDR *xdrs;
 369      enum_t *ep;
 370 {
 371   enum sizecheck
 372     {
 373       SIZEVAL
 374     };                          /* used to find the size of an enum */
 375
 376   /*
 377    * enums are treated as ints
 378    */
 379   if (sizeof (enum sizecheck) == 4)
 380     {
 381 #if INT_MAX < LONG_MAX
 382       long l;
 383
 384       switch (xdrs->x_op)
 385         {
 386         case XDR_ENCODE:
 387           l = *ep;
 388           return XDR_PUTLONG (xdrs, &l);
 389
 390         case XDR_DECODE:
 391           if (!XDR_GETLONG (xdrs, &l))
 392             {
 393               return FALSE;
 394             }
 395           *ep = l;
 396         case XDR_FREE:
 397           return TRUE;
 398
 399         }
 400       return FALSE;
 401 #else
 402       return xdr_long (xdrs, (long *) ep);
 403 #endif
 404     }
 405   else if (sizeof (enum sizecheck) == sizeof (short))
 406     {
 407       return xdr_short (xdrs, (short *) ep);
 408     }
 409   else
 410     {
 411       return FALSE;
 412     }
 413 }
 414
 415 /*
 416  * XDR opaque data
 417  * Allows the specification of a fixed size sequence of opaque bytes.
 418  * cp points to the opaque object and cnt gives the byte length.
 419  */
 420 bool_t
 421 xdr_opaque (xdrs, cp, cnt)
 422      XDR *xdrs;
 423      caddr_t cp;
 424      u_int cnt;
 425 {
 426   u_int rndup;
 427   static char crud[BYTES_PER_XDR_UNIT];
 428
 429   /*
 430    * if no data we are done
 431    */
 432   if (cnt == 0)
 433     return TRUE;
 434
 435   /*
 436    * round byte count to full xdr units
 437    */
 438   rndup = cnt % BYTES_PER_XDR_UNIT;
 439   if (rndup > 0)
 440     rndup = BYTES_PER_XDR_UNIT - rndup;
 441
 442   switch (xdrs->x_op)
 443     {
 444     case XDR_DECODE:
 445       if (!XDR_GETBYTES (xdrs, cp, cnt))
 446         {
 447           return FALSE;
 448         }
 449       if (rndup == 0)
 450         return TRUE;
 451       return XDR_GETBYTES (xdrs, (caddr_t)crud, rndup);
 452
 453     case XDR_ENCODE:
 454       if (!XDR_PUTBYTES (xdrs, cp, cnt))
 455         {
 456           return FALSE;
 457         }
 458       if (rndup == 0)
 459         return TRUE;
 460       return XDR_PUTBYTES (xdrs, xdr_zero, rndup);
 461
 462     case XDR_FREE:
 463       return TRUE;
 464     }
 465   return FALSE;
 466 }
 467
 468 /*
 469  * XDR counted bytes
 470  * *cpp is a pointer to the bytes, *sizep is the count.
 471  * If *cpp is NULL maxsize bytes are allocated
 472  */
 473 bool_t
 474 xdr_bytes (xdrs, cpp, sizep, maxsize)
 475      XDR *xdrs;
 476      char **cpp;
 477      u_int *sizep;
 478      u_int maxsize;
 479 {
 480   char *sp = *cpp;      /* sp is the actual string pointer */
 481   u_int nodesize;
 482
 483   /*
 484    * first deal with the length since xdr bytes are counted
 485    */
 486   if (!xdr_u_int (xdrs, sizep))
 487     {
 488       return FALSE;
 489     }
 490   nodesize = *sizep;
 491   if ((nodesize > maxsize) && (xdrs->x_op != XDR_FREE))
 492     {
 493       return FALSE;
 494     }
 495
 496   /*
 497    * now deal with the actual bytes
 498    */
 499   switch (xdrs->x_op)
 500     {
 501     case XDR_DECODE:
 502       if (nodesize == 0)
 503         {
 504           return TRUE;
 505         }
 506       if (sp == NULL)
 507         {
 508           *cpp = sp = (char *) mem_alloc (nodesize);
 509         }
 510       if (sp == NULL)
 511         {
 512           (void) fprintf (stderr, "xdr_bytes: out of memory\n");
 513           return FALSE;
 514         }
 515       /* fall into ... */
 516
 517     case XDR_ENCODE:
 518       return xdr_opaque (xdrs, sp, nodesize);
 519
 520     case XDR_FREE:
 521       if (sp != NULL)
 522         {
 523           mem_free (sp, nodesize);
 524           *cpp = NULL;
 525         }
 526       return TRUE;
 527     }
 528   return FALSE;
 529 }
 530
 531 /*
 532  * Implemented here due to commonality of the object.
 533  */
 534 bool_t
 535 xdr_netobj (xdrs, np)
 536      XDR *xdrs;
 537      struct netobj *np;
 538 {
 539
 540   return xdr_bytes (xdrs, &np->n_bytes, &np->n_len, MAX_NETOBJ_SZ);
 541 }
 542
 543 /*
 544  * XDR a discriminated union
 545  * Support routine for discriminated unions.
 546  * You create an array of xdrdiscrim structures, terminated with
 547  * an entry with a null procedure pointer.  The routine gets
 548  * the discriminant value and then searches the array of xdrdiscrims
 549  * looking for that value.  It calls the procedure given in the xdrdiscrim
 550  * to handle the discriminant.  If there is no specific routine a default
 551  * routine may be called.
 552  * If there is no specific or default routine an error is returned.
 553  */
 554 bool_t
 555 xdr_union (xdrs, dscmp, unp, choices, dfault)
 556      XDR *xdrs;
 557      enum_t *dscmp;             /* enum to decide which arm to work on */
 558      char *unp;                 /* the union itself */
 559      const struct xdr_discrim *choices; /* [value, xdr proc] for each arm */
 560      xdrproc_t dfault;          /* default xdr routine */
 561 {
 562   enum_t dscm;
 563
 564   /*
 565    * we deal with the discriminator;  it's an enum
 566    */
 567   if (!xdr_enum (xdrs, dscmp))
 568     {
 569       return FALSE;
 570     }
 571   dscm = *dscmp;
 572
 573   /*
 574    * search choices for a value that matches the discriminator.
 575    * if we find one, execute the xdr routine for that value.
 576    */
 577   for (; choices->proc != NULL_xdrproc_t; choices++)
 578     {
 579       if (choices->value == dscm)
 580         return (*(choices->proc)) (xdrs, unp, LASTUNSIGNED);
 581     }
 582
 583   /*
 584    * no match - execute the default xdr routine if there is one
 585    */
 586   return ((dfault == NULL_xdrproc_t) ? FALSE :
 587           (*dfault) (xdrs, unp, LASTUNSIGNED));
 588 }
 589
 590
 591 /*
 592  * Non-portable xdr primitives.
 593  * Care should be taken when moving these routines to new architectures.
 594  */
 595
 596
 597 /*
 598  * XDR null terminated ASCII strings
 599  * xdr_string deals with "C strings" - arrays of bytes that are
 600  * terminated by a NULL character.  The parameter cpp references a
 601  * pointer to storage; If the pointer is null, then the necessary
 602  * storage is allocated.  The last parameter is the max allowed length
 603  * of the string as specified by a protocol.
 604  */
 605 bool_t
 606 xdr_string (xdrs, cpp, maxsize)
 607      XDR *xdrs;
 608      char **cpp;
 609      u_int maxsize;
 610 {
 611   char *sp = *cpp;      /* sp is the actual string pointer */
 612   u_int size;
 613   u_int nodesize;
 614
 615   /*
 616    * first deal with the length since xdr strings are counted-strings
 617    */
 618   switch (xdrs->x_op)
 619     {
 620     case XDR_FREE:
 621       if (sp == NULL)
 622         {
 623           return TRUE;          /* already free */
 624         }
 625       /* fall through... */
 626     case XDR_ENCODE:
 627       if (sp == NULL)
 628         return FALSE;
 629       size = strlen (sp);
 630       break;
 631     case XDR_DECODE:
 632       break;
 633     }
 634   if (!xdr_u_int (xdrs, &size))
 635     {
 636       return FALSE;
 637     }
 638   if (size > maxsize)
 639     {
 640       return FALSE;
 641     }
 642   nodesize = size + 1;
 643
 644   /*
 645    * now deal with the actual bytes
 646    */
 647   switch (xdrs->x_op)
 648     {
 649     case XDR_DECODE:
 650       if (nodesize == 0)
 651         {
 652           return TRUE;
 653         }
 654       if (sp == NULL)
 655         *cpp = sp = (char *) mem_alloc (nodesize);
 656       if (sp == NULL)
 657         {
 658           (void) fprintf (stderr, "xdr_string: out of memory\n");
 659           return FALSE;
 660         }
 661       sp[size] = 0;
 662       /* fall into ... */
 663
 664     case XDR_ENCODE:
 665       return xdr_opaque (xdrs, sp, size);
 666
 667     case XDR_FREE:
 668       mem_free (sp, nodesize);
 669       *cpp = NULL;
 670       return TRUE;
 671     }
 672   return FALSE;
 673 }
 674
 675 /*
 676  * Wrapper for xdr_string that can be called directly from
 677  * routines like clnt_call
 678  */
 679 bool_t
 680 xdr_wrapstring (xdrs, cpp)
 681      XDR *xdrs;
 682      char **cpp;
 683 {
 684   if (xdr_string (xdrs, cpp, LASTUNSIGNED))
 685     {
 686       return TRUE;
 687     }
 688   return FALSE;
 689 }