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 long integers
 156  * same as xdr_u_long - open coded to save a proc call!
 157  */
 158 bool_t
 159 xdr_long (XDR *xdrs, long *lp)
 160 {
 161
 162   if (xdrs->x_op == XDR_ENCODE)
 163     return XDR_PUTLONG (xdrs, lp);
 164
 165   if (xdrs->x_op == XDR_DECODE)
 166     return XDR_GETLONG (xdrs, lp);
 167
 168   if (xdrs->x_op == XDR_FREE)
 169     return TRUE;
 170
 171   return FALSE;
 172 }
 173
 174 /*
 175  * XDR unsigned long integers
 176  * same as xdr_long - open coded to save a proc call!
 177  */
 178 bool_t
 179 xdr_u_long (XDR *xdrs, u_long *ulp)
 180 {
 181   switch (xdrs->x_op)
 182     {
 183     case XDR_DECODE:
 184       return XDR_GETLONG (xdrs, (long *) ulp);
 185
 186     case XDR_ENCODE:
 187       return XDR_PUTLONG (xdrs, (long *) ulp);
 188
 189     case XDR_FREE:
 190       return TRUE;
 191     }
 192   return FALSE;
 193 }
 194
 195 /*
 196  * XDR hyper integers
 197  * same as xdr_u_hyper - open coded to save a proc call!
 198  */
 199 bool_t
 200 xdr_hyper (XDR *xdrs, quad_t *llp)
 201 {
 202   long t1;
 203   long t2;
 204
 205   if (xdrs->x_op == XDR_ENCODE)
 206     {
 207       t1 = (long) ((*llp) >> 32);
 208       t2 = (long) (*llp);
 209       return (XDR_PUTLONG(xdrs, &t1) && XDR_PUTLONG(xdrs, &t2));
 210     }
 211
 212   if (xdrs->x_op == XDR_DECODE)
 213     {
 214       if (!XDR_GETLONG(xdrs, &t1) || !XDR_GETLONG(xdrs, &t2))
 215         return FALSE;
 216       *llp = ((quad_t) t1) << 32;
 217       *llp |= t2;
 218       return TRUE;
 219     }
 220
 221   if (xdrs->x_op == XDR_FREE)
 222     return TRUE;
 223
 224   return FALSE;
 225 }
 226
 227
 228 /*
 229  * XDR hyper integers
 230  * same as xdr_hyper - open coded to save a proc call!
 231  */
 232 bool_t
 233 xdr_u_hyper (XDR *xdrs, u_quad_t *ullp)
 234 {
 235   unsigned long t1;
 236   unsigned long t2;
 237
 238   if (xdrs->x_op == XDR_ENCODE)
 239     {
 240       t1 = (unsigned long) ((*ullp) >> 32);
 241       t2 = (unsigned long) (*ullp);
 242       return (XDR_PUTLONG(xdrs, &t1) && XDR_PUTLONG(xdrs, &t2));
 243     }
 244
 245   if (xdrs->x_op == XDR_DECODE)
 246     {
 247       if (!XDR_GETLONG(xdrs, &t1) || !XDR_GETLONG(xdrs, &t2))
 248         return FALSE;
 249       *ullp = ((u_quad_t) t1) << 32;
 250       *ullp |= t2;
 251       return TRUE;
 252     }
 253
 254   if (xdrs->x_op == XDR_FREE)
 255     return TRUE;
 256
 257   return FALSE;
 258 }
 259
 260 bool_t
 261 xdr_longlong_t (XDR *xdrs, quad_t *llp)
 262 {
 263   return xdr_hyper (xdrs, llp);
 264 }
 265
 266 bool_t
 267 xdr_u_longlong_t (XDR *xdrs, u_quad_t *ullp)
 268 {
 269   return xdr_u_hyper (xdrs, ullp);
 270 }
 271
 272 /*
 273  * XDR short integers
 274  */
 275 bool_t
 276 xdr_short (XDR *xdrs, short *sp)
 277 {
 278   long l;
 279
 280   switch (xdrs->x_op)
 281     {
 282     case XDR_ENCODE:
 283       l = (long) *sp;
 284       return XDR_PUTLONG (xdrs, &l);
 285
 286     case XDR_DECODE:
 287       if (!XDR_GETLONG (xdrs, &l))
 288         {
 289           return FALSE;
 290         }
 291       *sp = (short) l;
 292       return TRUE;
 293
 294     case XDR_FREE:
 295       return TRUE;
 296     }
 297   return FALSE;
 298 }
 299
 300 /*
 301  * XDR unsigned short integers
 302  */
 303 bool_t
 304 xdr_u_short (XDR *xdrs, u_short *usp)
 305 {
 306   u_long l;
 307
 308   switch (xdrs->x_op)
 309     {
 310     case XDR_ENCODE:
 311       l = (u_long) * usp;
 312       return XDR_PUTLONG (xdrs, &l);
 313
 314     case XDR_DECODE:
 315       if (!XDR_GETLONG (xdrs, &l))
 316         {
 317           return FALSE;
 318         }
 319       *usp = (u_short) l;
 320       return TRUE;
 321
 322     case XDR_FREE:
 323       return TRUE;
 324     }
 325   return FALSE;
 326 }
 327
 328
 329 /*
 330  * XDR a char
 331  */
 332 bool_t
 333 xdr_char (XDR *xdrs, char *cp)
 334 {
 335   int i;
 336
 337   i = (*cp);
 338   if (!xdr_int (xdrs, &i))
 339     {
 340       return FALSE;
 341     }
 342   *cp = i;
 343   return TRUE;
 344 }
 345
 346 /*
 347  * XDR an unsigned char
 348  */
 349 bool_t
 350 xdr_u_char (XDR *xdrs, u_char *cp)
 351 {
 352   u_int u;
 353
 354   u = (*cp);
 355   if (!xdr_u_int (xdrs, &u))
 356     {
 357       return FALSE;
 358     }
 359   *cp = u;
 360   return TRUE;
 361 }
 362
 363 /*
 364  * XDR booleans
 365  */
 366 bool_t
 367 xdr_bool (XDR *xdrs, bool_t *bp)
 368 {
 369   long lb;
 370
 371   switch (xdrs->x_op)
 372     {
 373     case XDR_ENCODE:
 374       lb = *bp ? XDR_TRUE : XDR_FALSE;
 375       return XDR_PUTLONG (xdrs, &lb);
 376
 377     case XDR_DECODE:
 378       if (!XDR_GETLONG (xdrs, &lb))
 379         {
 380           return FALSE;
 381         }
 382       *bp = (lb == XDR_FALSE) ? FALSE : TRUE;
 383       return TRUE;
 384
 385     case XDR_FREE:
 386       return TRUE;
 387     }
 388   return FALSE;
 389 }
 390
 391 /*
 392  * XDR enumerations
 393  */
 394 bool_t
 395 xdr_enum (XDR *xdrs, enum_t *ep)
 396 {
 397   enum sizecheck
 398     {
 399       SIZEVAL
 400     };                          /* used to find the size of an enum */
 401
 402   /*
 403    * enums are treated as ints
 404    */
 405   if (sizeof (enum sizecheck) == 4)
 406     {
 407 #if INT_MAX < LONG_MAX
 408       long l;
 409
 410       switch (xdrs->x_op)
 411         {
 412         case XDR_ENCODE:
 413           l = *ep;
 414           return XDR_PUTLONG (xdrs, &l);
 415
 416         case XDR_DECODE:
 417           if (!XDR_GETLONG (xdrs, &l))
 418             {
 419               return FALSE;
 420             }
 421           *ep = l;
 422         case XDR_FREE:
 423           return TRUE;
 424
 425         }
 426       return FALSE;
 427 #else
 428       return xdr_long (xdrs, (long *) ep);
 429 #endif
 430     }
 431   else if (sizeof (enum sizecheck) == sizeof (short))
 432     {
 433       return xdr_short (xdrs, (short *) ep);
 434     }
 435   else
 436     {
 437       return FALSE;
 438     }
 439 }
 440
 441 /*
 442  * XDR opaque data
 443  * Allows the specification of a fixed size sequence of opaque bytes.
 444  * cp points to the opaque object and cnt gives the byte length.
 445  */
 446 bool_t
 447 xdr_opaque (XDR *xdrs, caddr_t cp, u_int cnt)
 448 {
 449   u_int rndup;
 450   static char crud[BYTES_PER_XDR_UNIT];
 451
 452   /*
 453    * if no data we are done
 454    */
 455   if (cnt == 0)
 456     return TRUE;
 457
 458   /*
 459    * round byte count to full xdr units
 460    */
 461   rndup = cnt % BYTES_PER_XDR_UNIT;
 462   if (rndup > 0)
 463     rndup = BYTES_PER_XDR_UNIT - rndup;
 464
 465   switch (xdrs->x_op)
 466     {
 467     case XDR_DECODE:
 468       if (!XDR_GETBYTES (xdrs, cp, cnt))
 469         {
 470           return FALSE;
 471         }
 472       if (rndup == 0)
 473         return TRUE;
 474       return XDR_GETBYTES (xdrs, (caddr_t)crud, rndup);
 475
 476     case XDR_ENCODE:
 477       if (!XDR_PUTBYTES (xdrs, cp, cnt))
 478         {
 479           return FALSE;
 480         }
 481       if (rndup == 0)
 482         return TRUE;
 483       return XDR_PUTBYTES (xdrs, xdr_zero, rndup);
 484
 485     case XDR_FREE:
 486       return TRUE;
 487     }
 488   return FALSE;
 489 }
 490
 491 /*
 492  * XDR counted bytes
 493  * *cpp is a pointer to the bytes, *sizep is the count.
 494  * If *cpp is NULL maxsize bytes are allocated
 495  */
 496 bool_t
 497 xdr_bytes (xdrs, cpp, sizep, maxsize)
 498      XDR *xdrs;
 499      char **cpp;
 500      u_int *sizep;
 501      u_int maxsize;
 502 {
 503   char *sp = *cpp;      /* sp is the actual string pointer */
 504   u_int nodesize;
 505
 506   /*
 507    * first deal with the length since xdr bytes are counted
 508    */
 509   if (!xdr_u_int (xdrs, sizep))
 510     {
 511       return FALSE;
 512     }
 513   nodesize = *sizep;
 514   if ((nodesize > maxsize) && (xdrs->x_op != XDR_FREE))
 515     {
 516       return FALSE;
 517     }
 518
 519   /*
 520    * now deal with the actual bytes
 521    */
 522   switch (xdrs->x_op)
 523     {
 524     case XDR_DECODE:
 525       if (nodesize == 0)
 526         {
 527           return TRUE;
 528         }
 529       if (sp == NULL)
 530         {
 531           *cpp = sp = (char *) mem_alloc (nodesize);
 532         }
 533       if (sp == NULL)
 534         {
 535           (void) fprintf (stderr, "xdr_bytes: out of memory\n");
 536           return FALSE;
 537         }
 538       /* fall into ... */
 539
 540     case XDR_ENCODE:
 541       return xdr_opaque (xdrs, sp, nodesize);
 542
 543     case XDR_FREE:
 544       if (sp != NULL)
 545         {
 546           mem_free (sp, nodesize);
 547           *cpp = NULL;
 548         }
 549       return TRUE;
 550     }
 551   return FALSE;
 552 }
 553
 554 /*
 555  * Implemented here due to commonality of the object.
 556  */
 557 bool_t
 558 xdr_netobj (xdrs, np)
 559      XDR *xdrs;
 560      struct netobj *np;
 561 {
 562
 563   return xdr_bytes (xdrs, &np->n_bytes, &np->n_len, MAX_NETOBJ_SZ);
 564 }
 565
 566 /*
 567  * XDR a discriminated union
 568  * Support routine for discriminated unions.
 569  * You create an array of xdrdiscrim structures, terminated with
 570  * an entry with a null procedure pointer.  The routine gets
 571  * the discriminant value and then searches the array of xdrdiscrims
 572  * looking for that value.  It calls the procedure given in the xdrdiscrim
 573  * to handle the discriminant.  If there is no specific routine a default
 574  * routine may be called.
 575  * If there is no specific or default routine an error is returned.
 576  */
 577 bool_t
 578 xdr_union (xdrs, dscmp, unp, choices, dfault)
 579      XDR *xdrs;
 580      enum_t *dscmp;             /* enum to decide which arm to work on */
 581      char *unp;                 /* the union itself */
 582      const struct xdr_discrim *choices; /* [value, xdr proc] for each arm */
 583      xdrproc_t dfault;          /* default xdr routine */
 584 {
 585   enum_t dscm;
 586
 587   /*
 588    * we deal with the discriminator;  it's an enum
 589    */
 590   if (!xdr_enum (xdrs, dscmp))
 591     {
 592       return FALSE;
 593     }
 594   dscm = *dscmp;
 595
 596   /*
 597    * search choices for a value that matches the discriminator.
 598    * if we find one, execute the xdr routine for that value.
 599    */
 600   for (; choices->proc != NULL_xdrproc_t; choices++)
 601     {
 602       if (choices->value == dscm)
 603         return (*(choices->proc)) (xdrs, unp, LASTUNSIGNED);
 604     }
 605
 606   /*
 607    * no match - execute the default xdr routine if there is one
 608    */
 609   return ((dfault == NULL_xdrproc_t) ? FALSE :
 610           (*dfault) (xdrs, unp, LASTUNSIGNED));
 611 }
 612
 613
 614 /*
 615  * Non-portable xdr primitives.
 616  * Care should be taken when moving these routines to new architectures.
 617  */
 618
 619
 620 /*
 621  * XDR null terminated ASCII strings
 622  * xdr_string deals with "C strings" - arrays of bytes that are
 623  * terminated by a NULL character.  The parameter cpp references a
 624  * pointer to storage; If the pointer is null, then the necessary
 625  * storage is allocated.  The last parameter is the max allowed length
 626  * of the string as specified by a protocol.
 627  */
 628 bool_t
 629 xdr_string (xdrs, cpp, maxsize)
 630      XDR *xdrs;
 631      char **cpp;
 632      u_int maxsize;
 633 {
 634   char *sp = *cpp;      /* sp is the actual string pointer */
 635   u_int size;
 636   u_int nodesize;
 637
 638   /*
 639    * first deal with the length since xdr strings are counted-strings
 640    */
 641   switch (xdrs->x_op)
 642     {
 643     case XDR_FREE:
 644       if (sp == NULL)
 645         {
 646           return TRUE;          /* already free */
 647         }
 648       /* fall through... */
 649     case XDR_ENCODE:
 650       if (sp == NULL)
 651         return FALSE;
 652       size = strlen (sp);
 653       break;
 654     case XDR_DECODE:
 655       break;
 656     }
 657   if (!xdr_u_int (xdrs, &size))
 658     {
 659       return FALSE;
 660     }
 661   if (size > maxsize)
 662     {
 663       return FALSE;
 664     }
 665   nodesize = size + 1;
 666
 667   /*
 668    * now deal with the actual bytes
 669    */
 670   switch (xdrs->x_op)
 671     {
 672     case XDR_DECODE:
 673       if (nodesize == 0)
 674         {
 675           return TRUE;
 676         }
 677       if (sp == NULL)
 678         *cpp = sp = (char *) mem_alloc (nodesize);
 679       if (sp == NULL)
 680         {
 681           (void) fprintf (stderr, "xdr_string: out of memory\n");
 682           return FALSE;
 683         }
 684       sp[size] = 0;
 685       /* fall into ... */
 686
 687     case XDR_ENCODE:
 688       return xdr_opaque (xdrs, sp, size);
 689
 690     case XDR_FREE:
 691       mem_free (sp, nodesize);
 692       *cpp = NULL;
 693       return TRUE;
 694     }
 695   return FALSE;
 696 }
 697
 698 /*
 699  * Wrapper for xdr_string that can be called directly from
 700  * routines like clnt_call
 701  */
 702 bool_t
 703 xdr_wrapstring (xdrs, cpp)
 704      XDR *xdrs;
 705      char **cpp;
 706 {
 707   if (xdr_string (xdrs, cpp, LASTUNSIGNED))
 708     {
 709       return TRUE;
 710     }
 711   return FALSE;
 712 }