server/object.c

   1 /*
   2  * Server-side objects
   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 <stdlib.h>
  27 #include <stdio.h>
  28 #include <string.h>
  29 #include <unistd.h>
  30 #include <stdarg.h>
  31
  32 #include "ntstatus.h"
  33 #define WIN32_NO_STATUS
  34 #include "winternl.h"
  35
  36 #include "file.h"
  37 #include "process.h"
  38 #include "thread.h"
  39 #include "unicode.h"
  40 #include "security.h"
  41
  42
  43 struct object_name
  44 {
  45     struct list         entry;           /* entry in the hash list */
  46     struct object      *obj;             /* object owning this name */
  47     struct object      *parent;          /* parent object */
  48     data_size_t         len;             /* name length in bytes */
  49     WCHAR               name[1];
  50 };
  51
  52 struct namespace
  53 {
  54     unsigned int        hash_size;       /* size of hash table */
  55     struct list         names[1];        /* array of hash entry lists */
  56 };
  57
  58
  59 #ifdef DEBUG_OBJECTS
  60 static struct list object_list = LIST_INIT(object_list);
  61 static struct list static_object_list = LIST_INIT(static_object_list);
  62
  63 void dump_objects(void)
  64 {
  65     struct list *p;
  66
  67     LIST_FOR_EACH( p, &static_object_list )
  68     {
  69         struct object *ptr = LIST_ENTRY( p, struct object, obj_list );
  70         fprintf( stderr, "%p:%d: ", ptr, ptr->refcount );
  71         ptr->ops->dump( ptr, 1 );
  72     }
  73     LIST_FOR_EACH( p, &object_list )
  74     {
  75         struct object *ptr = LIST_ENTRY( p, struct object, obj_list );
  76         fprintf( stderr, "%p:%d: ", ptr, ptr->refcount );
  77         ptr->ops->dump( ptr, 1 );
  78     }
  79 }
  80
  81 void close_objects(void)
  82 {
  83     struct list *ptr;
  84
  85     /* release the static objects */
  86     while ((ptr = list_head( &static_object_list )))
  87     {
  88         struct object *obj = LIST_ENTRY( ptr, struct object, obj_list );
  89         /* move it back to the standard list before freeing */
  90         list_remove( &obj->obj_list );
  91         list_add_head( &object_list, &obj->obj_list );
  92         release_object( obj );
  93     }
  94
  95     dump_objects();  /* dump any remaining objects */
  96 }
  97
  98 #endif  /* DEBUG_OBJECTS */
  99
 100 /*****************************************************************/
 101
 102 /* malloc replacement */
 103 void *mem_alloc( size_t size )
 104 {
 105     void *ptr = malloc( size );
 106     if (ptr) memset( ptr, 0x55, size );
 107     else set_error( STATUS_NO_MEMORY );
 108     return ptr;
 109 }
 110
 111 /* duplicate a block of memory */
 112 void *memdup( const void *data, size_t len )
 113 {
 114     void *ptr = malloc( len );
 115     if (ptr) memcpy( ptr, data, len );
 116     else set_error( STATUS_NO_MEMORY );
 117     return ptr;
 118 }
 119
 120
 121 /*****************************************************************/
 122
 123 static int get_name_hash( const struct namespace *namespace, const WCHAR *name, data_size_t len )
 124 {
 125     WCHAR hash = 0;
 126     len /= sizeof(WCHAR);
 127     while (len--) hash ^= tolowerW(*name++);
 128     return hash % namespace->hash_size;
 129 }
 130
 131 /* allocate a name for an object */
 132 static struct object_name *alloc_name( const struct unicode_str *name )
 133 {
 134     struct object_name *ptr;
 135
 136     if ((ptr = mem_alloc( sizeof(*ptr) + name->len - sizeof(ptr->name) )))
 137     {
 138         ptr->len = name->len;
 139         ptr->parent = NULL;
 140         memcpy( ptr->name, name->str, name->len );
 141     }
 142     return ptr;
 143 }
 144
 145 /* free the name of an object */
 146 static void free_name( struct object *obj )
 147 {
 148     struct object_name *ptr = obj->name;
 149     list_remove( &ptr->entry );
 150     if (ptr->parent) release_object( ptr->parent );
 151     free( ptr );
 152 }
 153
 154 /* set the name of an existing object */
 155 static void set_object_name( struct namespace *namespace,
 156                              struct object *obj, struct object_name *ptr )
 157 {
 158     int hash = get_name_hash( namespace, ptr->name, ptr->len );
 159
 160     list_add_head( &namespace->names[hash], &ptr->entry );
 161     ptr->obj = obj;
 162     obj->name = ptr;
 163 }
 164
 165 /* get the name of an existing object */
 166 const WCHAR *get_object_name( struct object *obj, data_size_t *len )
 167 {
 168     struct object_name *ptr = obj->name;
 169     if (!ptr) return NULL;
 170     *len = ptr->len;
 171     return ptr->name;
 172 }
 173
 174 /* get the full path name of an existing object */
 175 WCHAR *get_object_full_name( struct object *obj, data_size_t *ret_len )
 176 {
 177     static const WCHAR backslash = '\\';
 178     struct object *ptr = obj;
 179     data_size_t len = 0;
 180     char *ret;
 181
 182     while (ptr && ptr->name)
 183     {
 184         struct object_name *name = ptr->name;
 185         len += name->len + sizeof(WCHAR);
 186         ptr = name->parent;
 187     }
 188     if (!len) return NULL;
 189     if (!(ret = malloc( len ))) return NULL;
 190
 191     *ret_len = len;
 192     while (obj && obj->name)
 193     {
 194         struct object_name *name = obj->name;
 195         memcpy( ret + len - name->len, name->name, name->len );
 196         len -= name->len + sizeof(WCHAR);
 197         memcpy( ret + len, &backslash, sizeof(WCHAR) );
 198         obj = name->parent;
 199     }
 200     return (WCHAR *)ret;
 201 }
 202
 203 /* allocate and initialize an object */
 204 void *alloc_object( const struct object_ops *ops )
 205 {
 206     struct object *obj = mem_alloc( ops->size );
 207     if (obj)
 208     {
 209         obj->refcount     = 1;
 210         obj->handle_count = 0;
 211         obj->ops          = ops;
 212         obj->name         = NULL;
 213         obj->sd           = NULL;
 214         list_init( &obj->wait_queue );
 215 #ifdef DEBUG_OBJECTS
 216         list_add_head( &object_list, &obj->obj_list );
 217 #endif
 218         return obj;
 219     }
 220     return NULL;
 221 }
 222
 223 void *create_object( struct namespace *namespace, const struct object_ops *ops,
 224                      const struct unicode_str *name, struct object *parent )
 225 {
 226     struct object *obj;
 227     struct object_name *name_ptr;
 228
 229     if (!(name_ptr = alloc_name( name ))) return NULL;
 230     if ((obj = alloc_object( ops )))
 231     {
 232         set_object_name( namespace, obj, name_ptr );
 233         if (parent) name_ptr->parent = grab_object( parent );
 234     }
 235     else
 236         free( name_ptr );
 237     return obj;
 238 }
 239
 240 void *create_named_object( struct namespace *namespace, const struct object_ops *ops,
 241                            const struct unicode_str *name, unsigned int attributes )
 242 {
 243     struct object *obj;
 244
 245     if (!name || !name->len)
 246     {
 247         if ((obj = alloc_object( ops ))) clear_error();
 248         return obj;
 249     }
 250
 251     if ((obj = find_object( namespace, name, attributes )))
 252     {
 253         if (attributes & OBJ_OPENIF && obj->ops == ops)
 254             set_error( STATUS_OBJECT_NAME_EXISTS );
 255         else
 256         {
 257             release_object( obj );
 258             obj = NULL;
 259             if (attributes & OBJ_OPENIF)
 260                 set_error( STATUS_OBJECT_TYPE_MISMATCH );
 261             else
 262                 set_error( STATUS_OBJECT_NAME_COLLISION );
 263         }
 264         return obj;
 265     }
 266     if ((obj = create_object( namespace, ops, name, NULL ))) clear_error();
 267     return obj;
 268 }
 269
 270 /* dump the name of an object to stderr */
 271 void dump_object_name( struct object *obj )
 272 {
 273     if (!obj->name) fprintf( stderr, "name=\"\"" );
 274     else
 275     {
 276         fprintf( stderr, "name=L\"" );
 277         dump_strW( obj->name->name, obj->name->len/sizeof(WCHAR), stderr, "\"\"" );
 278         fputc( '\"', stderr );
 279     }
 280 }
 281
 282 /* unlink a named object from its namespace, without freeing the object itself */
 283 void unlink_named_object( struct object *obj )
 284 {
 285     if (obj->name) free_name( obj );
 286     obj->name = NULL;
 287 }
 288
 289 /* mark an object as being stored statically, i.e. only released at shutdown */
 290 void make_object_static( struct object *obj )
 291 {
 292 #ifdef DEBUG_OBJECTS
 293     list_remove( &obj->obj_list );
 294     list_add_head( &static_object_list, &obj->obj_list );
 295 #endif
 296 }
 297
 298 /* grab an object (i.e. increment its refcount) and return the object */
 299 struct object *grab_object( void *ptr )
 300 {
 301     struct object *obj = (struct object *)ptr;
 302     assert( obj->refcount < INT_MAX );
 303     obj->refcount++;
 304     return obj;
 305 }
 306
 307 /* release an object (i.e. decrement its refcount) */
 308 void release_object( void *ptr )
 309 {
 310     struct object *obj = (struct object *)ptr;
 311     assert( obj->refcount );
 312     if (!--obj->refcount)
 313     {
 314         assert( !obj->handle_count );
 315         /* if the refcount is 0, nobody can be in the wait queue */
 316         assert( list_empty( &obj->wait_queue ));
 317         obj->ops->destroy( obj );
 318         if (obj->name) free_name( obj );
 319         free( obj->sd );
 320 #ifdef DEBUG_OBJECTS
 321         list_remove( &obj->obj_list );
 322         memset( obj, 0xaa, obj->ops->size );
 323 #endif
 324         free( obj );
 325     }
 326 }
 327
 328 /* find an object by its name; the refcount is incremented */
 329 struct object *find_object( const struct namespace *namespace, const struct unicode_str *name,
 330                             unsigned int attributes )
 331 {
 332     const struct list *list;
 333     struct list *p;
 334
 335     if (!name || !name->len) return NULL;
 336
 337     list = &namespace->names[ get_name_hash( namespace, name->str, name->len ) ];
 338     LIST_FOR_EACH( p, list )
 339     {
 340         const struct object_name *ptr = LIST_ENTRY( p, struct object_name, entry );
 341         if (ptr->len != name->len) continue;
 342         if (attributes & OBJ_CASE_INSENSITIVE)
 343         {
 344             if (!strncmpiW( ptr->name, name->str, name->len/sizeof(WCHAR) ))
 345                 return grab_object( ptr->obj );
 346         }
 347         else
 348         {
 349             if (!memcmp( ptr->name, name->str, name->len ))
 350                 return grab_object( ptr->obj );
 351         }
 352     }
 353     return NULL;
 354 }
 355
 356 /* find an object by its index; the refcount is incremented */
 357 struct object *find_object_index( const struct namespace *namespace, unsigned int index )
 358 {
 359     unsigned int i;
 360
 361     /* FIXME: not efficient at all */
 362     for (i = 0; i < namespace->hash_size; i++)
 363     {
 364         const struct object_name *ptr;
 365         LIST_FOR_EACH_ENTRY( ptr, &namespace->names[i], const struct object_name, entry )
 366         {
 367             if (!index--) return grab_object( ptr->obj );
 368         }
 369     }
 370     set_error( STATUS_NO_MORE_ENTRIES );
 371     return NULL;
 372 }
 373
 374 /* allocate a namespace */
 375 struct namespace *create_namespace( unsigned int hash_size )
 376 {
 377     struct namespace *namespace;
 378     unsigned int i;
 379
 380     namespace = mem_alloc( sizeof(*namespace) + (hash_size - 1) * sizeof(namespace->names[0]) );
 381     if (namespace)
 382     {
 383         namespace->hash_size      = hash_size;
 384         for (i = 0; i < hash_size; i++) list_init( &namespace->names[i] );
 385     }
 386     return namespace;
 387 }
 388
 389 /* functions for unimplemented/default object operations */
 390
 391 struct object_type *no_get_type( struct object *obj )
 392 {
 393     return NULL;
 394 }
 395
 396 int no_add_queue( struct object *obj, struct wait_queue_entry *entry )
 397 {
 398     set_error( STATUS_OBJECT_TYPE_MISMATCH );
 399     return 0;
 400 }
 401
 402 void no_satisfied( struct object *obj, struct wait_queue_entry *entry )
 403 {
 404 }
 405
 406 int no_signal( struct object *obj, unsigned int access )
 407 {
 408     set_error( STATUS_OBJECT_TYPE_MISMATCH );
 409     return 0;
 410 }
 411
 412 struct fd *no_get_fd( struct object *obj )
 413 {
 414     set_error( STATUS_OBJECT_TYPE_MISMATCH );
 415     return NULL;
 416 }
 417
 418 unsigned int no_map_access( struct object *obj, unsigned int access )
 419 {
 420     if (access & GENERIC_READ)    access |= STANDARD_RIGHTS_READ;
 421     if (access & GENERIC_WRITE)   access |= STANDARD_RIGHTS_WRITE;
 422     if (access & GENERIC_EXECUTE) access |= STANDARD_RIGHTS_EXECUTE;
 423     if (access & GENERIC_ALL)     access |= STANDARD_RIGHTS_ALL;
 424     return access & ~(GENERIC_READ | GENERIC_WRITE | GENERIC_EXECUTE | GENERIC_ALL);
 425 }
 426
 427 struct security_descriptor *default_get_sd( struct object *obj )
 428 {
 429     return obj->sd;
 430 }
 431
 432 int set_sd_defaults_from_token( struct object *obj, const struct security_descriptor *sd,
 433                                 unsigned int set_info, struct token *token )
 434 {
 435     struct security_descriptor new_sd, *new_sd_ptr;
 436     int present;
 437     const SID *owner = NULL, *group = NULL;
 438     const ACL *sacl, *dacl;
 439     char *ptr;
 440
 441     if (!set_info) return 1;
 442
 443     new_sd.control = sd->control & ~SE_SELF_RELATIVE;
 444
 445     if (set_info & OWNER_SECURITY_INFORMATION && sd->owner_len)
 446     {
 447         owner = sd_get_owner( sd );
 448         new_sd.owner_len = sd->owner_len;
 449     }
 450     else if (obj->sd && obj->sd->owner_len)
 451     {
 452         owner = sd_get_owner( obj->sd );
 453         new_sd.owner_len = obj->sd->owner_len;
 454     }
 455     else if (token)
 456     {
 457         owner = token_get_user( token );
 458         new_sd.owner_len = security_sid_len( owner );
 459     }
 460     else new_sd.owner_len = 0;
 461
 462     if (set_info & GROUP_SECURITY_INFORMATION && sd->group_len)
 463     {
 464         group = sd_get_group( sd );
 465         new_sd.group_len = sd->group_len;
 466     }
 467     else if (obj->sd && obj->sd->group_len)
 468     {
 469         group = sd_get_group( obj->sd );
 470         new_sd.group_len = obj->sd->group_len;
 471     }
 472     else if (token)
 473     {
 474         group = token_get_primary_group( token );
 475         new_sd.group_len = security_sid_len( group );
 476     }
 477     else new_sd.group_len = 0;
 478
 479     new_sd.control |= SE_SACL_PRESENT;
 480     sacl = sd_get_sacl( sd, &present );
 481     if (set_info & SACL_SECURITY_INFORMATION && present)
 482         new_sd.sacl_len = sd->sacl_len;
 483     else
 484     {
 485         if (obj->sd) sacl = sd_get_sacl( obj->sd, &present );
 486
 487         if (obj->sd && present)
 488             new_sd.sacl_len = obj->sd->sacl_len;
 489         else
 490             new_sd.sacl_len = 0;
 491     }
 492
 493     new_sd.control |= SE_DACL_PRESENT;
 494     dacl = sd_get_dacl( sd, &present );
 495     if (set_info & DACL_SECURITY_INFORMATION && present)
 496         new_sd.dacl_len = sd->dacl_len;
 497     else
 498     {
 499         if (obj->sd) dacl = sd_get_dacl( obj->sd, &present );
 500
 501         if (obj->sd && present)
 502             new_sd.dacl_len = obj->sd->dacl_len;
 503         else if (token)
 504         {
 505             dacl = token_get_default_dacl( token );
 506             new_sd.dacl_len = dacl->AclSize;
 507         }
 508         else new_sd.dacl_len = 0;
 509     }
 510
 511     ptr = mem_alloc( sizeof(new_sd) + new_sd.owner_len + new_sd.group_len +
 512                      new_sd.sacl_len + new_sd.dacl_len );
 513     if (!ptr) return 0;
 514     new_sd_ptr = (struct security_descriptor*)ptr;
 515
 516     memcpy( ptr, &new_sd, sizeof(new_sd) );
 517     ptr += sizeof(new_sd);
 518     memcpy( ptr, owner, new_sd.owner_len );
 519     ptr += new_sd.owner_len;
 520     memcpy( ptr, group, new_sd.group_len );
 521     ptr += new_sd.group_len;
 522     memcpy( ptr, sacl, new_sd.sacl_len );
 523     ptr += new_sd.sacl_len;
 524     memcpy( ptr, dacl, new_sd.dacl_len );
 525
 526     free( obj->sd );
 527     obj->sd = new_sd_ptr;
 528     return 1;
 529 }
 530
 531 /** Set the security descriptor using the current primary token for defaults. */
 532 int default_set_sd( struct object *obj, const struct security_descriptor *sd,
 533                     unsigned int set_info )
 534 {
 535     return set_sd_defaults_from_token( obj, sd, set_info, current->process->token );
 536 }
 537
 538 struct object *no_lookup_name( struct object *obj, struct unicode_str *name,
 539                                unsigned int attr )
 540 {
 541     return NULL;
 542 }
 543
 544 struct object *no_open_file( struct object *obj, unsigned int access, unsigned int sharing,
 545                              unsigned int options )
 546 {
 547     set_error( STATUS_OBJECT_TYPE_MISMATCH );
 548     return NULL;
 549 }
 550
 551 int no_close_handle( struct object *obj, struct process *process, obj_handle_t handle )
 552 {
 553     return 1;  /* ok to close */
 554 }
 555
 556 void no_destroy( struct object *obj )
 557 {
 558 }