source/rpc_parse/parse_prs.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    Samba memory buffer functions
   5    Copyright (C) Andrew Tridgell              1992-1997
   6    Copyright (C) Luke Kenneth Casson Leighton 1996-1997
   7    Copyright (C) Jeremy Allison 1999.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 2 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22 */
  23
  24 extern int DEBUGLEVEL;
  25
  26 #include "includes.h"
  27
  28
  29 /*******************************************************************
  30 dump a prs to a file
  31  ********************************************************************/
  32 void prs_dump(char *name, int v, prs_struct *ps)
  33 {
  34         int fd, i;
  35         pstring fname;
  36         if (DEBUGLEVEL < 50) return;
  37         for (i=1;i<100;i++) {
  38                 if (v != -1) {
  39                         slprintf(fname,sizeof(fname), "/tmp/%s_%d.%d.prs", name, v, i);
  40                 } else {
  41                         slprintf(fname,sizeof(fname), "/tmp/%s.%d.prs", name, i);
  42                 }
  43                 fd = open(fname, O_WRONLY|O_CREAT|O_EXCL, 0644);
  44                 if (fd != -1 || errno != EEXIST) break;
  45         }
  46         if (fd != -1) {
  47                 write(fd, ps->data_p + ps->data_offset, ps->grow_size - ps->data_offset);
  48                 close(fd);
  49                 DEBUG(0,("created %s\n", fname));
  50         }
  51 }
  52
  53
  54
  55 /*******************************************************************
  56  debug output for parsing info.
  57
  58  XXXX side-effect of this function is to increase the debug depth XXXX
  59
  60  ********************************************************************/
  61 void prs_debug(prs_struct *ps, int depth, char *desc, char *fn_name)
  62 {
  63         DEBUG(5+depth, ("%s%06x %s %s\n", tab_depth(depth), ps->data_offset, fn_name, desc));
  64 }
  65
  66
  67 /*******************************************************************
  68  Initialise a parse structure - malloc the data if requested.
  69  ********************************************************************/
  70 BOOL prs_init(prs_struct *ps, uint32 size, uint8 align, BOOL io)
  71 {
  72         ZERO_STRUCTP(ps);
  73         ps->io = io;
  74         ps->bigendian_data = False;
  75         ps->align = align;
  76         ps->is_dynamic = False;
  77         ps->data_offset = 0;
  78         ps->buffer_size = 0;
  79         ps->data_p = NULL;
  80
  81         if (size != 0) {
  82                 ps->buffer_size = size;
  83                 if((ps->data_p = (char *)malloc((size_t)size)) == NULL) {
  84                         DEBUG(0,("prs_init: malloc fail for %u bytes.\n", (unsigned int)size));
  85                         return False;
  86                 }
  87                 ps->is_dynamic = True; /* We own this memory. */
  88         }
  89
  90         return True;
  91 }
  92
  93 /*******************************************************************
  94  read from a socket into memory.
  95  ********************************************************************/
  96 BOOL prs_read(prs_struct *ps, int fd, size_t len, int timeout)
  97 {
  98         BOOL ok;
  99         size_t prev_size = ps->buffer_size;
 100         if (!prs_grow(ps, len))
 101         {
 102                 return False;
 103         }
 104
 105         if (timeout > 0)
 106         {
 107                 ok = (read_with_timeout(fd, &ps->data_p[prev_size],
 108                                             len, len,timeout) == len);
 109         }
 110         else
 111         {
 112                 ok = (read_data(fd, &ps->data_p[prev_size], len) == len);
 113         }
 114         return ok;
 115 }
 116
 117 /*******************************************************************
 118  Delete the memory in a parse structure - if we own it.
 119  ********************************************************************/
 120
 121 void prs_mem_free(prs_struct *ps)
 122 {
 123         if(ps->is_dynamic && (ps->data_p != NULL))
 124                 free(ps->data_p);
 125         ps->is_dynamic = False;
 126         ps->data_p = NULL;
 127         ps->buffer_size = 0;
 128         ps->data_offset = 0;
 129 }
 130
 131 /*******************************************************************
 132  Hand some already allocated memory to a prs_struct.
 133  ********************************************************************/
 134
 135 void prs_give_memory(prs_struct *ps, char *buf, uint32 size, BOOL is_dynamic)
 136 {
 137         ps->is_dynamic = is_dynamic;
 138         ps->data_p = buf;
 139         ps->buffer_size = size;
 140 }
 141
 142 /*******************************************************************
 143  Take some memory back from a prs_struct.
 144  ********************************************************************/
 145
 146 char *prs_take_memory(prs_struct *ps, uint32 *psize)
 147 {
 148         char *ret = ps->data_p;
 149         if(psize)
 150                 *psize = ps->buffer_size;
 151         ps->is_dynamic = False;
 152         prs_mem_free(ps);
 153         return ret;
 154 }
 155
 156 /*******************************************************************
 157  Set a prs_struct to exactly a given size. Will grow or tuncate if neccessary.
 158  ********************************************************************/
 159
 160 BOOL prs_set_buffer_size(prs_struct *ps, uint32 newsize)
 161 {
 162         if (newsize > ps->buffer_size)
 163                 return prs_force_grow(ps, newsize - ps->buffer_size);
 164
 165         if (newsize < ps->buffer_size) {
 166                 char *new_data_p = Realloc(ps->data_p, newsize);
 167                 /* if newsize is zero, Realloc acts like free() & returns NULL*/
 168                 if (new_data_p == NULL && newsize != 0) {
 169                         DEBUG(0,("prs_set_buffer_size: Realloc failure for size %u.\n",
 170                                 (unsigned int)newsize));
 171                         DEBUG(0,("prs_set_buffer_size: Reason %s\n",strerror(errno)));
 172                         return False;
 173                 }
 174                 ps->data_p = new_data_p;
 175                 ps->buffer_size = newsize;
 176         }
 177
 178         return True;
 179 }
 180
 181 /*******************************************************************
 182  Attempt, if needed, to grow a data buffer.
 183  Also depends on the data stream mode (io).
 184  ********************************************************************/
 185
 186 BOOL prs_grow(prs_struct *ps, uint32 extra_space)
 187 {
 188         uint32 new_size;
 189         char *new_data;
 190
 191         ps->grow_size = MAX(ps->grow_size, ps->data_offset + extra_space);
 192
 193         if(ps->data_offset + extra_space <= ps->buffer_size)
 194                 return True;
 195
 196         /*
 197          * We cannot grow the buffer if we're not reading
 198          * into the prs_struct, or if we don't own the memory.
 199          */
 200
 201         if(UNMARSHALLING(ps) || !ps->is_dynamic) {
 202                 DEBUG(0,("prs_grow: Buffer overflow - unable to expand buffer by %u bytes.\n",
 203                                 (unsigned int)extra_space));
 204                 return False;
 205         }
 206
 207         /*
 208          * Decide how much extra space we really need.
 209          */
 210
 211         extra_space -= (ps->buffer_size - ps->data_offset);
 212         if(ps->buffer_size == 0) {
 213                 /*
 214                  * Ensure we have at least a PDU's length, or extra_space, whichever
 215                  * is greater.
 216                  */
 217
 218                 new_size = MAX(MAX_PDU_FRAG_LEN,extra_space);
 219
 220                 if((new_data = malloc(new_size)) == NULL) {
 221                         DEBUG(0,("prs_grow: Malloc failure for size %u.\n", (unsigned int)new_size));
 222                         return False;
 223                 }
 224                 memset(new_data, '\0', new_size );
 225         } else {
 226                 /*
 227                  * If the current buffer size is bigger than the space needed, just
 228                  * double it, else add extra_space.
 229                  */
 230                 new_size = MAX(ps->buffer_size*2, ps->buffer_size + extra_space);
 231
 232                 if ((new_data = Realloc(ps->data_p, new_size)) == NULL) {
 233                         DEBUG(0,("prs_grow: Realloc failure for size %u.\n",
 234                                 (unsigned int)new_size));
 235                         return False;
 236                 }
 237
 238                 memset(&new_data[ps->buffer_size], '\0', new_size - ps->buffer_size);
 239         }
 240         ps->buffer_size = new_size;
 241         ps->data_p = new_data;
 242
 243         return True;
 244 }
 245
 246 /*******************************************************************
 247  Attempt to force a data buffer to grow by len bytes.
 248  This is only used when appending more data onto a prs_struct
 249  when reading an rpc reply, before unmarshalling it.
 250  ********************************************************************/
 251
 252 BOOL prs_force_grow(prs_struct *ps, uint32 extra_space)
 253 {
 254         uint32 new_size = ps->buffer_size + extra_space;
 255         char *new_data;
 256
 257         if(!UNMARSHALLING(ps) || !ps->is_dynamic) {
 258                 DEBUG(0,("prs_force_grow: Buffer overflow - unable to expand buffer by %u bytes.\n",
 259                                 (unsigned int)extra_space));
 260                 return False;
 261         }
 262
 263         if((new_data = Realloc(ps->data_p, new_size)) == NULL) {
 264                 DEBUG(0,("prs_force_grow: Realloc failure for size %u.\n",
 265                         (unsigned int)new_size));
 266                 return False;
 267         }
 268
 269         memset(&new_data[ps->buffer_size], '\0', new_size - ps->buffer_size);
 270
 271         ps->buffer_size = new_size;
 272         ps->data_p = new_data;
 273
 274         return True;
 275 }
 276
 277 /*******************************************************************
 278  Get the data pointer (external interface).
 279  ********************************************************************/
 280
 281 char *prs_data_p(prs_struct *ps)
 282 {
 283         return ps->data_p;
 284 }
 285
 286 /*******************************************************************
 287  Get the current data size (external interface).
 288  ********************************************************************/
 289
 290 uint32 prs_data_size(prs_struct *ps)
 291 {
 292         return ps->buffer_size;
 293 }
 294
 295 /*******************************************************************
 296  Fetch the current offset (external interface).
 297  ********************************************************************/
 298
 299 uint32 prs_offset(prs_struct *ps)
 300 {
 301         return ps->data_offset;
 302 }
 303
 304 /*******************************************************************
 305  Set the current offset (external interface).
 306  ********************************************************************/
 307
 308 BOOL prs_set_offset(prs_struct *ps, uint32 offset)
 309 {
 310         if(offset <= ps->data_offset) {
 311                 ps->data_offset = offset;
 312                 return True;
 313         }
 314
 315         if(!prs_grow(ps, offset - ps->data_offset))
 316                 return False;
 317
 318         ps->data_offset = offset;
 319         return True;
 320 }
 321
 322 /*******************************************************************
 323  Append the data from one parse_struct into another.
 324  ********************************************************************/
 325
 326 BOOL prs_append_prs_data(prs_struct *dst, prs_struct *src)
 327 {
 328         if(!prs_grow(dst, prs_offset(src)))
 329                 return False;
 330
 331         memcpy(&dst->data_p[dst->data_offset], prs_data_p(src), (size_t)prs_offset(src));
 332         dst->data_offset += prs_offset(src);
 333
 334         return True;
 335 }
 336
 337 /*******************************************************************
 338  Append some data from one parse_struct into another.
 339  ********************************************************************/
 340
 341 BOOL prs_append_some_prs_data(prs_struct *dst, prs_struct *src, int32 start, uint32 len)
 342 {
 343         if (len == 0)
 344                 return True;
 345
 346         if(!prs_grow(dst, len))
 347                 return False;
 348
 349         memcpy(&dst->data_p[dst->data_offset], prs_data_p(src)+start, (size_t)len);
 350         dst->data_offset += len;
 351
 352         return True;
 353 }
 354
 355 /*******************************************************************
 356  Append the data from a buffer into a parse_struct.
 357  ********************************************************************/
 358
 359 BOOL prs_append_data(prs_struct *dst, char *src, uint32 len)
 360 {
 361         if(!prs_grow(dst, len))
 362                 return False;
 363
 364         memcpy(&dst->data_p[dst->data_offset], src, (size_t)len);
 365         dst->data_offset += len;
 366
 367         return True;
 368 }
 369
 370 /*******************************************************************
 371  Set the data as big-endian (external interface).
 372  ********************************************************************/
 373
 374 void prs_set_bigendian_data(prs_struct *ps)
 375 {
 376         ps->bigendian_data = True;
 377 }
 378
 379 /*******************************************************************
 380  Align a the data_len to a multiple of align bytes - filling with
 381  zeros.
 382  ********************************************************************/
 383
 384 BOOL prs_align(prs_struct *ps)
 385 {
 386         uint32 mod = ps->data_offset & (ps->align-1);
 387
 388         if (ps->align != 0 && mod != 0) {
 389                 uint32 extra_space = (ps->align - mod);
 390                 if(!prs_grow(ps, extra_space))
 391                         return False;
 392                 memset(&ps->data_p[ps->data_offset], '\0', (size_t)extra_space);
 393                 ps->data_offset += extra_space;
 394         }
 395
 396         return True;
 397 }
 398
 399 /*******************************************************************
 400  Ensure we can read/write to a given offset.
 401  ********************************************************************/
 402
 403 char *prs_mem_get(prs_struct *ps, uint32 extra_size)
 404 {
 405         if(UNMARSHALLING(ps)) {
 406                 /*
 407                  * If reading, ensure that we can read the requested size item.
 408                  */
 409                 if (ps->data_offset + extra_size > ps->buffer_size) {
 410                         DEBUG(0,("prs_mem_get: reading data of size %u would overrun buffer.\n",
 411                                         (unsigned int)extra_size ));
 412                         return NULL;
 413                 }
 414         } else {
 415                 /*
 416                  * Writing - grow the buffer if needed.
 417                  */
 418                 if(!prs_grow(ps, extra_size))
 419                         return False;
 420         }
 421         return &ps->data_p[ps->data_offset];
 422 }
 423
 424 /*******************************************************************
 425  Change the struct type.
 426  ********************************************************************/
 427
 428 void prs_switch_type(prs_struct *ps, BOOL io)
 429 {
 430         if ((ps->io ^ io) == True)
 431                 ps->io=io;
 432 }
 433
 434 /*******************************************************************
 435  Force a prs_struct to be dynamic even when it's size is 0.
 436  ********************************************************************/
 437
 438 void prs_force_dynamic(prs_struct *ps)
 439 {
 440         ps->is_dynamic=True;
 441 }
 442
 443 /*******************************************************************
 444  Stream a uint8.
 445  ********************************************************************/
 446
 447 BOOL prs_uint8(char *name, prs_struct *ps, int depth, uint8 *data8)
 448 {
 449         char *q = prs_mem_get(ps, sizeof(uint8));
 450         if (q == NULL)
 451                 return False;
 452
 453         DBG_RW_CVAL(name, depth, ps->data_offset, ps->io, q, *data8)
 454         ps->data_offset += sizeof(uint8);
 455
 456         return True;
 457 }
 458
 459 /*******************************************************************
 460  Stream a uint16.
 461  ********************************************************************/
 462
 463 BOOL prs_uint16(char *name, prs_struct *ps, int depth, uint16 *data16)
 464 {
 465         char *q = prs_mem_get(ps, sizeof(uint16));
 466         if (q == NULL)
 467                 return False;
 468
 469         DBG_RW_SVAL(name, depth, ps->data_offset, ps->io, ps->bigendian_data, q, *data16)
 470         ps->data_offset += sizeof(uint16);
 471
 472         return True;
 473 }
 474
 475 /*******************************************************************
 476  Stream a uint32.
 477  ********************************************************************/
 478
 479 BOOL prs_uint32(char *name, prs_struct *ps, int depth, uint32 *data32)
 480 {
 481         char *q = prs_mem_get(ps, sizeof(uint32));
 482         if (q == NULL)
 483                 return False;
 484
 485         DBG_RW_IVAL(name, depth, ps->data_offset, ps->io, ps->bigendian_data, q, *data32)
 486         ps->data_offset += sizeof(uint32);
 487
 488         return True;
 489 }
 490
 491 /******************************************************************
 492  Stream an array of uint8s. Length is number of uint8s.
 493  ********************************************************************/
 494
 495 BOOL prs_uint8s(BOOL charmode, char *name, prs_struct *ps, int depth, uint8 *data8s, int len)
 496 {
 497         char *q = prs_mem_get(ps, len * sizeof(uint8));
 498         if (q == NULL)
 499                 return False;
 500
 501         DBG_RW_PCVAL(charmode, name, depth, ps->data_offset, ps->io, q, data8s, len)
 502         ps->data_offset += (len * sizeof(uint8));
 503
 504         return True;
 505 }
 506
 507 /******************************************************************
 508  Stream an array of uint16s. Length is number of uint16s.
 509  ********************************************************************/
 510
 511 BOOL prs_uint16s(BOOL charmode, char *name, prs_struct *ps, int depth, uint16 *data16s, int len)
 512 {
 513         char *q = prs_mem_get(ps, len * sizeof(uint16));
 514         if (q == NULL)
 515                 return False;
 516
 517         DBG_RW_PSVAL(charmode, name, depth, ps->data_offset, ps->io, ps->bigendian_data, q, data16s, len)
 518         ps->data_offset += (len * sizeof(uint16));
 519
 520         return True;
 521 }
 522
 523 /******************************************************************
 524  Stream an array of uint32s. Length is number of uint32s.
 525  ********************************************************************/
 526
 527 BOOL prs_uint32s(BOOL charmode, char *name, prs_struct *ps, int depth, uint32 *data32s, int len)
 528 {
 529         char *q = prs_mem_get(ps, len * sizeof(uint32));
 530         if (q == NULL)
 531                 return False;
 532
 533         DBG_RW_PIVAL(charmode, name, depth, ps->data_offset, ps->io, ps->bigendian_data, q, data32s, len)
 534         ps->data_offset += (len * sizeof(uint32));
 535
 536         return True;
 537 }
 538
 539 /******************************************************************
 540  Stream a "not" unicode string, length/buffer specified separately,
 541  in byte chars. String is in little-endian format.
 542  ********************************************************************/
 543
 544 BOOL prs_buffer2(BOOL charmode, char *name, prs_struct *ps, int depth, BUFFER2 *str)
 545 {
 546         char *p = (char *)str->buffer;
 547         char *q = prs_mem_get(ps, str->buf_len);
 548         if (q == NULL)
 549                 return False;
 550
 551         /* If we're using big-endian, reverse to get little-endian. */
 552         if(ps->bigendian_data)
 553                 DBG_RW_PSVAL(charmode, name, depth, ps->data_offset, ps->io, ps->bigendian_data, q, p, str->buf_len/2)
 554         else
 555                 DBG_RW_PCVAL(charmode, name, depth, ps->data_offset, ps->io, q, p, str->buf_len)
 556         ps->data_offset += str->buf_len;
 557
 558         return True;
 559 }
 560
 561 /******************************************************************
 562  Stream a string, length/buffer specified separately,
 563  in uint8 chars.
 564  ********************************************************************/
 565
 566 BOOL prs_string2(BOOL charmode, char *name, prs_struct *ps, int depth, STRING2 *str)
 567 {
 568         char *q = prs_mem_get(ps, str->str_str_len * sizeof(uint8));
 569         if (q == NULL)
 570                 return False;
 571
 572         DBG_RW_PCVAL(charmode, name, depth, ps->data_offset, ps->io, q, str->buffer, str->str_max_len)
 573         ps->data_offset += (str->str_str_len * sizeof(uint8));
 574
 575         return True;
 576 }
 577
 578 /******************************************************************
 579  Stream a unicode string, length/buffer specified separately,
 580  in uint16 chars. We use DBG_RW_PCVAL, not DBG_RW_PSVAL here
 581  as the unicode string is already in little-endian format.
 582  ********************************************************************/
 583
 584 BOOL prs_unistr2(BOOL charmode, char *name, prs_struct *ps, int depth, UNISTR2 *str)
 585 {
 586         char *p = (char *)str->buffer;
 587         char *q = prs_mem_get(ps, str->uni_str_len * sizeof(uint16));
 588         if (q == NULL)
 589                 return False;
 590
 591         /* If we're using big-endian, reverse to get little-endian. */
 592         if(ps->bigendian_data)
 593                 DBG_RW_PSVAL(charmode, name, depth, ps->data_offset, ps->io, ps->bigendian_data, q, p, str->uni_str_len)
 594         else
 595                 DBG_RW_PCVAL(charmode, name, depth, ps->data_offset, ps->io, q, p, str->uni_str_len * 2)
 596         ps->data_offset += (str->uni_str_len * sizeof(uint16));
 597
 598         return True;
 599 }
 600
 601
 602
 603 /******************************************************************
 604  Stream a unicode string, length/buffer specified separately,
 605  in uint16 chars. We use DBG_RW_PCVAL, not DBG_RW_PSVAL here
 606  as the unicode string is already in little-endian format.
 607  ********************************************************************/
 608
 609 BOOL prs_unistr3(BOOL charmode, char *name, UNISTR3 *str, prs_struct *ps, int depth)
 610 {
 611         char *p = (char *)str->str.buffer;
 612         char *q = prs_mem_get(ps, str->uni_str_len * sizeof(uint16));
 613         if (q == NULL)
 614                 return False;
 615
 616         /* If we're using big-endian, reverse to get little-endian. */
 617         if(ps->bigendian_data)
 618                 DBG_RW_PSVAL(charmode, name, depth, ps->data_offset, ps->io, ps->bigendian_data, q, p, str->uni_str_len)
 619         else
 620                 DBG_RW_PCVAL(charmode, name, depth, ps->data_offset, ps->io, q, p, str->uni_str_len * 2)
 621         ps->data_offset += (str->uni_str_len * sizeof(uint16));
 622
 623         return True;
 624 }
 625
 626 /*******************************************************************
 627  Stream a unicode  null-terminated string. As the string is already
 628  in little-endian format then do it as a stream of bytes.
 629  ********************************************************************/
 630
 631 #ifndef RPCCLIENT_TEST
 632 BOOL prs_unistr(char *name, prs_struct *ps, int depth, UNISTR *str)
 633 {
 634         int len = 0;
 635         unsigned char *p = (unsigned char *)str->buffer;
 636         uint8 *start;
 637         char *q;
 638         char zero=0;
 639
 640         for(len = 0; len < (sizeof(str->buffer) / sizeof(str->buffer[0])) &&
 641                            str->buffer[len] != 0; len++)
 642                 ;
 643
 644         q = prs_mem_get(ps, (len+1)*2);
 645         if (q == NULL)
 646                 return False;
 647
 648         start = (uint8*)q;
 649
 650         for(len = 0; len < (sizeof(str->buffer) / sizeof(str->buffer[0])) &&
 651                            str->buffer[len] != 0; len++) {
 652                 if(ps->bigendian_data) {
 653                         RW_SVAL(ps->io, ps->bigendian_data, q, *p, 0);
 654                         p += 2;
 655                         q += 2;
 656                 } else {
 657                         RW_CVAL(ps->io, q, *p, 0);
 658                         p++;
 659                         q++;
 660                         RW_CVAL(ps->io, q, *p, 0);
 661                         p++;
 662                         q++;
 663                 }
 664         }
 665
 666         /*
 667          * even if the string is 'empty' (only an \0 char)
 668          * at this point the leading \0 hasn't been parsed.
 669          * so parse it now
 670          */
 671
 672         RW_CVAL(ps->io, q, zero, 0);
 673         q++;
 674         RW_CVAL(ps->io, q, zero, 0);
 675         q++;
 676
 677         len++;
 678
 679         ps->data_offset += len*2;
 680
 681         dump_data(5+depth, (char *)start, len * 2);
 682
 683         return True;
 684 }
 685 #else
 686 BOOL prs_unistr(char *name, prs_struct *ps, int depth, UNISTR *str)
 687 {
 688         int len = 0;
 689         unsigned char *p = (unsigned char *)str->buffer;
 690         uint8 *start;
 691         char *q;
 692         char zero=0;
 693
 694         if (MARSHALLING(ps)) {
 695
 696                 for(len = 0; len < (sizeof(str->buffer) / sizeof(str->buffer[0])) &&
 697                                    str->buffer[len] != 0; len++)
 698                         ;
 699
 700                 q = prs_mem_get(ps, (len+1)*2);
 701                 if (q == NULL)
 702                         return False;
 703
 704                 start = (uint8*)q;
 705
 706                 for(len = 0; len < (sizeof(str->buffer) / sizeof(str->buffer[0])) &&
 707                                    str->buffer[len] != 0; len++)
 708                 {
 709                         if(ps->bigendian_data)
 710                         {
 711                                 RW_SVAL(ps->io, ps->bigendian_data, q, *p, 0);
 712                                 p += 2;
 713                                 q += 2;
 714                         }
 715                         else
 716                         {
 717                                 RW_CVAL(ps->io, q, *p, 0);
 718                                 p++;
 719                                 q++;
 720                                 RW_CVAL(ps->io, q, *p, 0);
 721                                 p++;
 722                                 q++;
 723                         }
 724                 }
 725
 726                 /*
 727                  * even if the string is 'empty' (only an \0 char)
 728                  * at this point the leading \0 hasn't been parsed.
 729                  * so parse it now
 730                  */
 731
 732                 RW_CVAL(ps->io, q, zero, 0);
 733                 q++;
 734                 RW_CVAL(ps->io, q, zero, 0);
 735                 q++;
 736
 737                 len++;
 738
 739                 dump_data(5+depth, (char *)start, len * 2);
 740         }
 741         else { /* unmarshalling */
 742
 743                 len = -1;
 744                 q = prs_data_p(ps) + prs_offset(ps);
 745
 746                 do
 747                 {
 748                         len++;
 749
 750                         if(ps->bigendian_data)
 751                         {
 752                                 RW_SVAL(ps->io, ps->bigendian_data, q, *p, 0);
 753                                 p += 2;
 754                                 q += 2;
 755                         } else {
 756                                 RW_CVAL(ps->io, q, *p, 0);
 757                                 p++;
 758                                 q++;
 759                                 RW_CVAL(ps->io, q, *p, 0);
 760                                 p++;
 761                                 q++;
 762                         }
 763                 } while (len < (sizeof(str->buffer) / sizeof(str->buffer[0])) &&
 764                                    str->buffer[len] != 0);
 765         }
 766
 767         ps->data_offset += len*2;
 768
 769         return True;
 770 }
 771
 772 #endif  /* RPCCLIENT_TEST */
 773
 774
 775 /*******************************************************************
 776  Stream a null-terminated string.  len is strlen, and therefore does
 777  not include the null-termination character.
 778  ********************************************************************/
 779
 780 BOOL prs_string(char *name, prs_struct *ps, int depth, char *str, int len, int max_buf_size)
 781 {
 782         char *q;
 783         uint8 *start;
 784         int i;
 785
 786         len = MIN(len, (max_buf_size-1));
 787
 788         q = prs_mem_get(ps, len+1);
 789         if (q == NULL)
 790                 return False;
 791
 792         start = (uint8*)q;
 793
 794         for(i = 0; i < len; i++) {
 795                 RW_CVAL(ps->io, q, str[i],0);
 796                 q++;
 797         }
 798
 799         /* The terminating null. */
 800         str[i] = '\0';
 801
 802         if (MARSHALLING(ps)) {
 803                 RW_CVAL(ps->io, q, str[i], 0);
 804         }
 805
 806         ps->data_offset += len+1;
 807
 808         dump_data(5+depth, (char *)start, len);
 809
 810         return True;
 811 }
 812
 813 /*******************************************************************
 814  prs_uint16 wrapper. Call this and it sets up a pointer to where the
 815  uint16 should be stored, or gets the size if reading.
 816  ********************************************************************/
 817
 818 BOOL prs_uint16_pre(char *name, prs_struct *ps, int depth, uint16 *data16, uint32 *offset)
 819 {
 820         (*offset) = ps->data_offset;
 821         if (UNMARSHALLING(ps)) {
 822                 /* reading. */
 823                 return prs_uint16(name, ps, depth, data16);
 824         } else {
 825                 char *q = prs_mem_get(ps, sizeof(uint16));
 826                 if(q ==NULL)
 827                         return False;
 828                 ps->data_offset += sizeof(uint16);
 829         }
 830         return True;
 831 }
 832
 833 /*******************************************************************
 834  prs_uint16 wrapper.  call this and it retrospectively stores the size.
 835  does nothing on reading, as that is already handled by ...._pre()
 836  ********************************************************************/
 837
 838 BOOL prs_uint16_post(char *name, prs_struct *ps, int depth, uint16 *data16,
 839                                 uint32 ptr_uint16, uint32 start_offset)
 840 {
 841         if (MARSHALLING(ps)) {
 842                 /*
 843                  * Writing - temporarily move the offset pointer.
 844                  */
 845                 uint16 data_size = ps->data_offset - start_offset;
 846                 uint32 old_offset = ps->data_offset;
 847
 848                 ps->data_offset = ptr_uint16;
 849                 if(!prs_uint16(name, ps, depth, &data_size)) {
 850                         ps->data_offset = old_offset;
 851                         return False;
 852                 }
 853                 ps->data_offset = old_offset;
 854         } else {
 855                 ps->data_offset = start_offset + (uint32)(*data16);
 856         }
 857         return True;
 858 }
 859
 860 /*******************************************************************
 861  prs_uint32 wrapper. Call this and it sets up a pointer to where the
 862  uint32 should be stored, or gets the size if reading.
 863  ********************************************************************/
 864
 865 BOOL prs_uint32_pre(char *name, prs_struct *ps, int depth, uint32 *data32, uint32 *offset)
 866 {
 867         (*offset) = ps->data_offset;
 868         if (UNMARSHALLING(ps)) {
 869                 /* reading. */
 870                 return prs_uint32(name, ps, depth, data32);
 871         } else {
 872                 ps->data_offset += sizeof(uint32);
 873         }
 874         return True;
 875 }
 876
 877 /*******************************************************************
 878  prs_uint32 wrapper.  call this and it retrospectively stores the size.
 879  does nothing on reading, as that is already handled by ...._pre()
 880  ********************************************************************/
 881
 882 BOOL prs_uint32_post(char *name, prs_struct *ps, int depth, uint32 *data32,
 883                                 uint32 ptr_uint32, uint32 data_size)
 884 {
 885         if (MARSHALLING(ps)) {
 886                 /*
 887                  * Writing - temporarily move the offset pointer.
 888                  */
 889                 uint32 old_offset = ps->data_offset;
 890                 ps->data_offset = ptr_uint32;
 891                 if(!prs_uint32(name, ps, depth, &data_size)) {
 892                         ps->data_offset = old_offset;
 893                         return False;
 894                 }
 895                 ps->data_offset = old_offset;
 896         }
 897         return True;
 898 }
 899
 900 /* useful function to store a structure in rpc wire format */
 901 int tdb_prs_store(TDB_CONTEXT *tdb, char *keystr, prs_struct *ps)
 902 {
 903     TDB_DATA kbuf, dbuf;
 904     kbuf.dptr = keystr;
 905     kbuf.dsize = strlen(keystr)+1;
 906     dbuf.dptr = prs_data_p(ps);
 907     dbuf.dsize = prs_offset(ps);
 908     return tdb_store(tdb, kbuf, dbuf, TDB_REPLACE);
 909 }
 910
 911 /* useful function to fetch a structure into rpc wire format */
 912 int tdb_prs_fetch(TDB_CONTEXT *tdb, char *keystr, prs_struct *ps)
 913 {
 914     TDB_DATA kbuf, dbuf;
 915     kbuf.dptr = keystr;
 916     kbuf.dsize = strlen(keystr)+1;
 917
 918     dbuf = tdb_fetch(tdb, kbuf);
 919     if (!dbuf.dptr) return -1;
 920
 921     ZERO_STRUCTP(ps);
 922     prs_init(ps, 0, 4, UNMARSHALL);
 923     prs_give_memory(ps, dbuf.dptr, dbuf.dsize, True);
 924
 925     return 0;
 926 }