server/handle.c

   1 /*
   2  * Server-side handle management
   3  *
   4  * Copyright (C) 1998 Alexandre Julliard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  */
  20
  21 #include "config.h"
  22 #include "wine/port.h"
  23
  24 #include <assert.h>
  25 #include <limits.h>
  26 #include <string.h>
  27 #include <stdarg.h>
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30
  31 #include "ntstatus.h"
  32 #define WIN32_NO_STATUS
  33 #include "windef.h"
  34 #include "winternl.h"
  35
  36 #include "handle.h"
  37 #include "process.h"
  38 #include "thread.h"
  39 #include "security.h"
  40 #include "request.h"
  41
  42 struct handle_entry
  43 {
  44     struct object *ptr;       /* object */
  45     unsigned int   access;    /* access rights */
  46 };
  47
  48 struct handle_table
  49 {
  50     struct object        obj;         /* object header */
  51     struct process      *process;     /* process owning this table */
  52     int                  count;       /* number of allocated entries */
  53     int                  last;        /* last used entry */
  54     int                  free;        /* first entry that may be free */
  55     struct handle_entry *entries;     /* handle entries */
  56 };
  57
  58 static struct handle_table *global_table;
  59
  60 /* reserved handle access rights */
  61 #define RESERVED_SHIFT         26
  62 #define RESERVED_INHERIT       (HANDLE_FLAG_INHERIT << RESERVED_SHIFT)
  63 #define RESERVED_CLOSE_PROTECT (HANDLE_FLAG_PROTECT_FROM_CLOSE << RESERVED_SHIFT)
  64 #define RESERVED_ALL           (RESERVED_INHERIT | RESERVED_CLOSE_PROTECT)
  65
  66 #define MIN_HANDLE_ENTRIES  32
  67
  68
  69 /* handle to table index conversion */
  70
  71 /* handles are a multiple of 4 under NT; handle 0 is not used */
  72 static inline obj_handle_t index_to_handle( int index )
  73 {
  74     return (obj_handle_t)((unsigned long)(index + 1) << 2);
  75 }
  76 static inline int handle_to_index( obj_handle_t handle )
  77 {
  78     return ((unsigned long)handle >> 2) - 1;
  79 }
  80
  81 /* global handle conversion */
  82
  83 #define HANDLE_OBFUSCATOR 0x544a4def
  84
  85 static inline int handle_is_global( obj_handle_t handle)
  86 {
  87     return ((unsigned long)handle ^ HANDLE_OBFUSCATOR) < 0x10000;
  88 }
  89 static inline obj_handle_t handle_local_to_global( obj_handle_t handle )
  90 {
  91     if (!handle) return 0;
  92     return (obj_handle_t)((unsigned long)handle ^ HANDLE_OBFUSCATOR);
  93 }
  94 static inline obj_handle_t handle_global_to_local( obj_handle_t handle )
  95 {
  96     return (obj_handle_t)((unsigned long)handle ^ HANDLE_OBFUSCATOR);
  97 }
  98
  99
 100 static void handle_table_dump( struct object *obj, int verbose );
 101 static void handle_table_destroy( struct object *obj );
 102
 103 static const struct object_ops handle_table_ops =
 104 {
 105     sizeof(struct handle_table),     /* size */
 106     handle_table_dump,               /* dump */
 107     no_get_type,                     /* get_type */
 108     no_add_queue,                    /* add_queue */
 109     NULL,                            /* remove_queue */
 110     NULL,                            /* signaled */
 111     NULL,                            /* satisfied */
 112     no_signal,                       /* signal */
 113     no_get_fd,                       /* get_fd */
 114     no_map_access,                   /* map_access */
 115     default_get_sd,                  /* get_sd */
 116     default_set_sd,                  /* set_sd */
 117     no_lookup_name,                  /* lookup_name */
 118     no_open_file,                    /* open_file */
 119     no_close_handle,                 /* close_handle */
 120     handle_table_destroy             /* destroy */
 121 };
 122
 123 /* dump a handle table */
 124 static void handle_table_dump( struct object *obj, int verbose )
 125 {
 126     int i;
 127     struct handle_table *table = (struct handle_table *)obj;
 128     struct handle_entry *entry = table->entries;
 129
 130     assert( obj->ops == &handle_table_ops );
 131
 132     fprintf( stderr, "Handle table last=%d count=%d process=%p\n",
 133              table->last, table->count, table->process );
 134     if (!verbose) return;
 135     entry = table->entries;
 136     for (i = 0; i <= table->last; i++, entry++)
 137     {
 138         if (!entry->ptr) continue;
 139         fprintf( stderr, "    %p: %p %08x ",
 140                  index_to_handle(i), entry->ptr, entry->access );
 141         entry->ptr->ops->dump( entry->ptr, 0 );
 142     }
 143 }
 144
 145 /* destroy a handle table */
 146 static void handle_table_destroy( struct object *obj )
 147 {
 148     int i;
 149     struct handle_table *table = (struct handle_table *)obj;
 150     struct handle_entry *entry;
 151
 152     assert( obj->ops == &handle_table_ops );
 153
 154     /* first notify all objects that handles are being closed */
 155     if (table->process)
 156     {
 157         for (i = 0, entry = table->entries; i <= table->last; i++, entry++)
 158         {
 159             struct object *obj = entry->ptr;
 160             if (obj) obj->ops->close_handle( obj, table->process, index_to_handle(i) );
 161         }
 162     }
 163
 164     for (i = 0, entry = table->entries; i <= table->last; i++, entry++)
 165     {
 166         struct object *obj = entry->ptr;
 167         entry->ptr = NULL;
 168         if (obj) release_object( obj );
 169     }
 170     free( table->entries );
 171 }
 172
 173 /* allocate a new handle table */
 174 struct handle_table *alloc_handle_table( struct process *process, int count )
 175 {
 176     struct handle_table *table;
 177
 178     if (count < MIN_HANDLE_ENTRIES) count = MIN_HANDLE_ENTRIES;
 179     if (!(table = alloc_object( &handle_table_ops )))
 180         return NULL;
 181     table->process = process;
 182     table->count   = count;
 183     table->last    = -1;
 184     table->free    = 0;
 185     if ((table->entries = mem_alloc( count * sizeof(*table->entries) ))) return table;
 186     release_object( table );
 187     return NULL;
 188 }
 189
 190 /* grow a handle table */
 191 static int grow_handle_table( struct handle_table *table )
 192 {
 193     struct handle_entry *new_entries;
 194     int count = table->count;
 195
 196     if (count >= INT_MAX / 2) return 0;
 197     count *= 2;
 198     if (!(new_entries = realloc( table->entries, count * sizeof(struct handle_entry) )))
 199     {
 200         set_error( STATUS_NO_MEMORY );
 201         return 0;
 202     }
 203     table->entries = new_entries;
 204     table->count   = count;
 205     return 1;
 206 }
 207
 208 /* allocate the first free entry in the handle table */
 209 static obj_handle_t alloc_entry( struct handle_table *table, void *obj, unsigned int access )
 210 {
 211     struct handle_entry *entry = table->entries + table->free;
 212     int i;
 213
 214     for (i = table->free; i <= table->last; i++, entry++) if (!entry->ptr) goto found;
 215     if (i >= table->count)
 216     {
 217         if (!grow_handle_table( table )) return 0;
 218         entry = table->entries + i;  /* the entries may have moved */
 219     }
 220     table->last = i;
 221  found:
 222     table->free = i + 1;
 223     entry->ptr    = grab_object( obj );
 224     entry->access = access;
 225     return index_to_handle(i);
 226 }
 227
 228 /* allocate a handle for an object, incrementing its refcount */
 229 /* return the handle, or 0 on error */
 230 obj_handle_t alloc_handle_no_access_check( struct process *process, void *ptr, unsigned int access, unsigned int attr )
 231 {
 232     struct object *obj = ptr;
 233
 234     access &= ~RESERVED_ALL;
 235     if (attr & OBJ_INHERIT) access |= RESERVED_INHERIT;
 236     if (!process->handles)
 237     {
 238         set_error( STATUS_NO_MEMORY );
 239         return 0;
 240     }
 241     return alloc_entry( process->handles, obj, access );
 242 }
 243
 244 /* allocate a handle for an object, checking the dacl allows the process to */
 245 /* access it and incrementing its refcount */
 246 /* return the handle, or 0 on error */
 247 obj_handle_t alloc_handle( struct process *process, void *ptr, unsigned int access, unsigned int attr )
 248 {
 249     struct object *obj = ptr;
 250     access = obj->ops->map_access( obj, access );
 251     if (access && !check_object_access( obj, &access )) return 0;
 252     return alloc_handle_no_access_check( process, ptr, access, attr );
 253 }
 254
 255 /* allocate a global handle for an object, incrementing its refcount */
 256 /* return the handle, or 0 on error */
 257 static obj_handle_t alloc_global_handle_no_access_check( void *obj, unsigned int access )
 258 {
 259     if (!global_table)
 260     {
 261         if (!(global_table = (struct handle_table *)alloc_handle_table( NULL, 0 )))
 262             return 0;
 263         make_object_static( &global_table->obj );
 264     }
 265     return handle_local_to_global( alloc_entry( global_table, obj, access ));
 266 }
 267
 268 /* allocate a global handle for an object, checking the dacl allows the */
 269 /* process to access it and incrementing its refcount and incrementing its refcount */
 270 /* return the handle, or 0 on error */
 271 static obj_handle_t alloc_global_handle( void *obj, unsigned int access )
 272 {
 273     if (access && !check_object_access( obj, &access )) return 0;
 274     return alloc_global_handle_no_access_check( obj, access );
 275 }
 276
 277 /* return a handle entry, or NULL if the handle is invalid */
 278 static struct handle_entry *get_handle( struct process *process, obj_handle_t handle )
 279 {
 280     struct handle_table *table = process->handles;
 281     struct handle_entry *entry;
 282     int index;
 283
 284     if (handle_is_global(handle))
 285     {
 286         handle = handle_global_to_local(handle);
 287         table = global_table;
 288     }
 289     if (!table) goto error;
 290     index = handle_to_index( handle );
 291     if (index < 0) goto error;
 292     if (index > table->last) goto error;
 293     entry = table->entries + index;
 294     if (!entry->ptr) goto error;
 295     return entry;
 296
 297  error:
 298     set_error( STATUS_INVALID_HANDLE );
 299     return NULL;
 300 }
 301
 302 /* attempt to shrink a table */
 303 static void shrink_handle_table( struct handle_table *table )
 304 {
 305     struct handle_entry *entry = table->entries + table->last;
 306     struct handle_entry *new_entries;
 307     int count = table->count;
 308
 309     while (table->last >= 0)
 310     {
 311         if (entry->ptr) break;
 312         table->last--;
 313         entry--;
 314     }
 315     if (table->last >= count / 4) return;  /* no need to shrink */
 316     if (count < MIN_HANDLE_ENTRIES * 2) return;  /* too small to shrink */
 317     count /= 2;
 318     if (!(new_entries = realloc( table->entries, count * sizeof(*new_entries) ))) return;
 319     table->count   = count;
 320     table->entries = new_entries;
 321 }
 322
 323 /* copy the handle table of the parent process */
 324 /* return 1 if OK, 0 on error */
 325 struct handle_table *copy_handle_table( struct process *process, struct process *parent )
 326 {
 327     struct handle_table *parent_table = parent->handles;
 328     struct handle_table *table;
 329     int i;
 330
 331     assert( parent_table );
 332     assert( parent_table->obj.ops == &handle_table_ops );
 333
 334     if (!(table = (struct handle_table *)alloc_handle_table( process, parent_table->count )))
 335         return NULL;
 336
 337     if ((table->last = parent_table->last) >= 0)
 338     {
 339         struct handle_entry *ptr = table->entries;
 340         memcpy( ptr, parent_table->entries, (table->last + 1) * sizeof(struct handle_entry) );
 341         for (i = 0; i <= table->last; i++, ptr++)
 342         {
 343             if (!ptr->ptr) continue;
 344             if (ptr->access & RESERVED_INHERIT) grab_object( ptr->ptr );
 345             else ptr->ptr = NULL; /* don't inherit this entry */
 346         }
 347     }
 348     /* attempt to shrink the table */
 349     shrink_handle_table( table );
 350     return table;
 351 }
 352
 353 /* close a handle and decrement the refcount of the associated object */
 354 /* return 1 if OK, 0 on error */
 355 int close_handle( struct process *process, obj_handle_t handle )
 356 {
 357     struct handle_table *table;
 358     struct handle_entry *entry;
 359     struct object *obj;
 360
 361     if (!(entry = get_handle( process, handle ))) return 0;
 362     if (entry->access & RESERVED_CLOSE_PROTECT)
 363     {
 364         set_error( STATUS_HANDLE_NOT_CLOSABLE );
 365         return 0;
 366     }
 367     obj = entry->ptr;
 368     if (!obj->ops->close_handle( obj, process, handle ))
 369     {
 370         set_error( STATUS_HANDLE_NOT_CLOSABLE );
 371         return 0;
 372     }
 373     entry->ptr = NULL;
 374     table = handle_is_global(handle) ? global_table : process->handles;
 375     if (entry < table->entries + table->free) table->free = entry - table->entries;
 376     if (entry == table->entries + table->last) shrink_handle_table( table );
 377     release_object( obj );
 378     return 1;
 379 }
 380
 381 /* retrieve the object corresponding to one of the magic pseudo-handles */
 382 static inline struct object *get_magic_handle( obj_handle_t handle )
 383 {
 384     switch((unsigned long)handle)
 385     {
 386         case 0xfffffffe:  /* current thread pseudo-handle */
 387             return &current->obj;
 388         case 0x7fffffff:  /* current process pseudo-handle */
 389         case 0xffffffff:  /* current process pseudo-handle */
 390             return (struct object *)current->process;
 391         default:
 392             return NULL;
 393     }
 394 }
 395
 396 /* retrieve the object corresponding to a handle, incrementing its refcount */
 397 struct object *get_handle_obj( struct process *process, obj_handle_t handle,
 398                                unsigned int access, const struct object_ops *ops )
 399 {
 400     struct handle_entry *entry;
 401     struct object *obj;
 402
 403     if (!(obj = get_magic_handle( handle )))
 404     {
 405         if (!(entry = get_handle( process, handle ))) return NULL;
 406         if ((entry->access & access) != access)
 407         {
 408             set_error( STATUS_ACCESS_DENIED );
 409             return NULL;
 410         }
 411         obj = entry->ptr;
 412     }
 413     if (ops && (obj->ops != ops))
 414     {
 415         set_error( STATUS_OBJECT_TYPE_MISMATCH );  /* not the right type */
 416         return NULL;
 417     }
 418     return grab_object( obj );
 419 }
 420
 421 /* retrieve the access rights of a given handle */
 422 unsigned int get_handle_access( struct process *process, obj_handle_t handle )
 423 {
 424     struct handle_entry *entry;
 425
 426     if (get_magic_handle( handle )) return ~RESERVED_ALL;  /* magic handles have all access rights */
 427     if (!(entry = get_handle( process, handle ))) return 0;
 428     return entry->access & ~RESERVED_ALL;
 429 }
 430
 431 /* find the first inherited handle of the given type */
 432 /* this is needed for window stations and desktops (don't ask...) */
 433 obj_handle_t find_inherited_handle( struct process *process, const struct object_ops *ops )
 434 {
 435     struct handle_table *table = process->handles;
 436     struct handle_entry *ptr;
 437     int i;
 438
 439     if (!table) return 0;
 440
 441     for (i = 0, ptr = table->entries; i <= table->last; i++, ptr++)
 442     {
 443         if (!ptr->ptr) continue;
 444         if (ptr->ptr->ops != ops) continue;
 445         if (ptr->access & RESERVED_INHERIT) return index_to_handle(i);
 446     }
 447     return 0;
 448 }
 449
 450 /* enumerate handles of a given type */
 451 /* this is needed for window stations and desktops */
 452 obj_handle_t enumerate_handles( struct process *process, const struct object_ops *ops,
 453                                 unsigned int *index )
 454 {
 455     struct handle_table *table = process->handles;
 456     unsigned int i;
 457     struct handle_entry *entry;
 458
 459     if (!table) return 0;
 460
 461     for (i = *index, entry = &table->entries[i]; i <= table->last; i++, entry++)
 462     {
 463         if (!entry->ptr) continue;
 464         if (entry->ptr->ops != ops) continue;
 465         *index = i + 1;
 466         return index_to_handle(i);
 467     }
 468     return 0;
 469 }
 470
 471 /* get/set the handle reserved flags */
 472 /* return the old flags (or -1 on error) */
 473 static int set_handle_flags( struct process *process, obj_handle_t handle, int mask, int flags )
 474 {
 475     struct handle_entry *entry;
 476     unsigned int old_access;
 477
 478     if (get_magic_handle( handle ))
 479     {
 480         /* we can retrieve but not set info for magic handles */
 481         if (mask) set_error( STATUS_ACCESS_DENIED );
 482         return 0;
 483     }
 484     if (!(entry = get_handle( process, handle ))) return -1;
 485     old_access = entry->access;
 486     mask  = (mask << RESERVED_SHIFT) & RESERVED_ALL;
 487     flags = (flags << RESERVED_SHIFT) & mask;
 488     entry->access = (entry->access & ~mask) | flags;
 489     return (old_access & RESERVED_ALL) >> RESERVED_SHIFT;
 490 }
 491
 492 /* duplicate a handle */
 493 obj_handle_t duplicate_handle( struct process *src, obj_handle_t src_handle, struct process *dst,
 494                                unsigned int access, unsigned int attr, unsigned int options )
 495 {
 496     obj_handle_t res;
 497     struct handle_entry *entry;
 498     unsigned int src_access;
 499     struct object *obj = get_handle_obj( src, src_handle, 0, NULL );
 500
 501     if (!obj) return 0;
 502     if ((entry = get_handle( src, src_handle )))
 503         src_access = entry->access;
 504     else  /* pseudo-handle, give it full access */
 505     {
 506         src_access = obj->ops->map_access( obj, GENERIC_ALL );
 507         clear_error();
 508     }
 509     src_access &= ~RESERVED_ALL;
 510
 511     if (options & DUP_HANDLE_SAME_ACCESS)
 512         access = src_access;
 513     else
 514         access = obj->ops->map_access( obj, access ) & ~RESERVED_ALL;
 515
 516     /* asking for the more access rights than src_access? */
 517     if (access & ~src_access)
 518     {
 519         if (options & DUP_HANDLE_MAKE_GLOBAL)
 520             res = alloc_global_handle( obj, access );
 521         else
 522             res = alloc_handle( dst, obj, access, attr );
 523     }
 524     else
 525     {
 526         if (options & DUP_HANDLE_MAKE_GLOBAL)
 527             res = alloc_global_handle_no_access_check( obj, access );
 528         else
 529             res = alloc_handle_no_access_check( dst, obj, access, attr );
 530     }
 531
 532     release_object( obj );
 533     return res;
 534 }
 535
 536 /* open a new handle to an existing object */
 537 obj_handle_t open_object( const struct namespace *namespace, const struct unicode_str *name,
 538                           const struct object_ops *ops, unsigned int access, unsigned int attr )
 539 {
 540     obj_handle_t handle = 0;
 541     struct object *obj = find_object( namespace, name, attr );
 542     if (obj)
 543     {
 544         if (ops && obj->ops != ops)
 545             set_error( STATUS_OBJECT_TYPE_MISMATCH );
 546         else
 547             handle = alloc_handle( current->process, obj, access, attr );
 548         release_object( obj );
 549     }
 550     else
 551         set_error( STATUS_OBJECT_NAME_NOT_FOUND );
 552     return handle;
 553 }
 554
 555 /* return the size of the handle table of a given process */
 556 unsigned int get_handle_table_count( struct process *process )
 557 {
 558     if (!process->handles) return 0;
 559     return process->handles->count;
 560 }
 561
 562 /* close a handle */
 563 DECL_HANDLER(close_handle)
 564 {
 565     close_handle( current->process, req->handle );
 566 }
 567
 568 /* set a handle information */
 569 DECL_HANDLER(set_handle_info)
 570 {
 571     reply->old_flags = set_handle_flags( current->process, req->handle, req->mask, req->flags );
 572 }
 573
 574 /* duplicate a handle */
 575 DECL_HANDLER(dup_handle)
 576 {
 577     struct process *src, *dst;
 578
 579     reply->handle = 0;
 580     if ((src = get_process_from_handle( req->src_process, PROCESS_DUP_HANDLE )))
 581     {
 582         if (req->options & DUP_HANDLE_MAKE_GLOBAL)
 583         {
 584             reply->handle = duplicate_handle( src, req->src_handle, NULL,
 585                                               req->access, req->attributes, req->options );
 586         }
 587         else if ((dst = get_process_from_handle( req->dst_process, PROCESS_DUP_HANDLE )))
 588         {
 589             reply->handle = duplicate_handle( src, req->src_handle, dst,
 590                                               req->access, req->attributes, req->options );
 591             release_object( dst );
 592         }
 593         /* close the handle no matter what happened */
 594         if (req->options & DUP_HANDLE_CLOSE_SOURCE)
 595         {
 596             unsigned int err = get_error();  /* don't overwrite error from the above calls */
 597             reply->closed = close_handle( src, req->src_handle );
 598             set_error( err );
 599         }
 600         reply->self = (src == current->process);
 601         release_object( src );
 602     }
 603 }
 604
 605 DECL_HANDLER(get_object_info)
 606 {
 607     struct object *obj;
 608
 609     if (!(obj = get_handle_obj( current->process, req->handle, 0, NULL ))) return;
 610
 611     reply->access = get_handle_access( current->process, req->handle );
 612     reply->ref_count = obj->refcount;
 613     release_object( obj );
 614 }
 615
 616 DECL_HANDLER(set_security_object)
 617 {
 618     data_size_t sd_size = get_req_data_size();
 619     const struct security_descriptor *sd = get_req_data();
 620     struct object *obj;
 621     unsigned int access = 0;
 622
 623     if (!sd_is_valid( sd, sd_size ))
 624     {
 625         set_error( STATUS_ACCESS_VIOLATION );
 626         return;
 627     }
 628
 629     if (req->security_info & OWNER_SECURITY_INFORMATION ||
 630         req->security_info & GROUP_SECURITY_INFORMATION)
 631         access |= WRITE_OWNER;
 632     if (req->security_info & SACL_SECURITY_INFORMATION)
 633         access |= ACCESS_SYSTEM_SECURITY;
 634     if (req->security_info & DACL_SECURITY_INFORMATION)
 635         access |= WRITE_DAC;
 636
 637     if (!(obj = get_handle_obj( current->process, req->handle, access, NULL ))) return;
 638
 639     obj->ops->set_sd( obj, sd, req->security_info );
 640     release_object( obj );
 641 }
 642
 643 DECL_HANDLER(get_security_object)
 644 {
 645     const struct security_descriptor *sd;
 646     struct object *obj;
 647     unsigned int access = READ_CONTROL;
 648     struct security_descriptor req_sd;
 649     int present;
 650     const SID *owner, *group;
 651     const ACL *sacl, *dacl;
 652
 653     if (req->security_info & SACL_SECURITY_INFORMATION)
 654         access |= ACCESS_SYSTEM_SECURITY;
 655
 656     if (!(obj = get_handle_obj( current->process, req->handle, access, NULL ))) return;
 657
 658     sd = obj->ops->get_sd( obj );
 659     if (sd)
 660     {
 661         req_sd.control = sd->control & ~SE_SELF_RELATIVE;
 662
 663         owner = sd_get_owner( sd );
 664         if (req->security_info & OWNER_SECURITY_INFORMATION)
 665             req_sd.owner_len = sd->owner_len;
 666         else
 667             req_sd.owner_len = 0;
 668
 669         group = sd_get_group( sd );
 670         if (req->security_info & GROUP_SECURITY_INFORMATION)
 671             req_sd.group_len = sd->group_len;
 672         else
 673             req_sd.group_len = 0;
 674
 675         req_sd.control |= SE_SACL_PRESENT;
 676         sacl = sd_get_sacl( sd, &present );
 677         if (req->security_info & SACL_SECURITY_INFORMATION && present)
 678             req_sd.sacl_len = sd->sacl_len;
 679         else
 680             req_sd.sacl_len = 0;
 681
 682         req_sd.control |= SE_DACL_PRESENT;
 683         dacl = sd_get_dacl( sd, &present );
 684         if (req->security_info & DACL_SECURITY_INFORMATION && present)
 685             req_sd.dacl_len = sd->dacl_len;
 686         else
 687             req_sd.dacl_len = 0;
 688
 689         reply->sd_len = sizeof(req_sd) + req_sd.owner_len + req_sd.group_len +
 690             req_sd.sacl_len + req_sd.dacl_len;
 691         if (reply->sd_len <= get_reply_max_size())
 692         {
 693             char *ptr = set_reply_data_size(reply->sd_len);
 694
 695             memcpy( ptr, &req_sd, sizeof(req_sd) );
 696             ptr += sizeof(req_sd);
 697             memcpy( ptr, owner, req_sd.owner_len );
 698             ptr += req_sd.owner_len;
 699             memcpy( ptr, group, req_sd.group_len );
 700             ptr += req_sd.group_len;
 701             memcpy( ptr, sacl, req_sd.sacl_len );
 702             ptr += req_sd.sacl_len;
 703             memcpy( ptr, dacl, req_sd.dacl_len );
 704         }
 705         else
 706             set_error(STATUS_BUFFER_TOO_SMALL);
 707     }
 708
 709     release_object( obj );
 710 }