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->ops      = ops;
 211         obj->name     = NULL;
 212         obj->sd       = NULL;
 213         list_init( &obj->wait_queue );
 214 #ifdef DEBUG_OBJECTS
 215         list_add_head( &object_list, &obj->obj_list );
 216 #endif
 217         return obj;
 218     }
 219     return NULL;
 220 }
 221
 222 void *create_object( struct namespace *namespace, const struct object_ops *ops,
 223                      const struct unicode_str *name, struct object *parent )
 224 {
 225     struct object *obj;
 226     struct object_name *name_ptr;
 227
 228     if (!(name_ptr = alloc_name( name ))) return NULL;
 229     if ((obj = alloc_object( ops )))
 230     {
 231         set_object_name( namespace, obj, name_ptr );
 232         if (parent) name_ptr->parent = grab_object( parent );
 233     }
 234     else
 235         free( name_ptr );
 236     return obj;
 237 }
 238
 239 void *create_named_object( struct namespace *namespace, const struct object_ops *ops,
 240                            const struct unicode_str *name, unsigned int attributes )
 241 {
 242     struct object *obj;
 243
 244     if (!name || !name->len) return alloc_object( ops );
 245
 246     if ((obj = find_object( namespace, name, attributes )))
 247     {
 248         if (attributes & OBJ_OPENIF && obj->ops == ops)
 249             set_error( STATUS_OBJECT_NAME_EXISTS );
 250         else
 251         {
 252             release_object( obj );
 253             obj = NULL;
 254             if (attributes & OBJ_OPENIF)
 255                 set_error( STATUS_OBJECT_TYPE_MISMATCH );
 256             else
 257                 set_error( STATUS_OBJECT_NAME_COLLISION );
 258         }
 259         return obj;
 260     }
 261     if ((obj = create_object( namespace, ops, name, NULL ))) clear_error();
 262     return obj;
 263 }
 264
 265 /* dump the name of an object to stderr */
 266 void dump_object_name( struct object *obj )
 267 {
 268     if (!obj->name) fprintf( stderr, "name=\"\"" );
 269     else
 270     {
 271         fprintf( stderr, "name=L\"" );
 272         dump_strW( obj->name->name, obj->name->len/sizeof(WCHAR), stderr, "\"\"" );
 273         fputc( '\"', stderr );
 274     }
 275 }
 276
 277 /* unlink a named object from its namespace, without freeing the object itself */
 278 void unlink_named_object( struct object *obj )
 279 {
 280     if (obj->name) free_name( obj );
 281     obj->name = NULL;
 282 }
 283
 284 /* mark an object as being stored statically, i.e. only released at shutdown */
 285 void make_object_static( struct object *obj )
 286 {
 287 #ifdef DEBUG_OBJECTS
 288     list_remove( &obj->obj_list );
 289     list_add_head( &static_object_list, &obj->obj_list );
 290 #endif
 291 }
 292
 293 /* grab an object (i.e. increment its refcount) and return the object */
 294 struct object *grab_object( void *ptr )
 295 {
 296     struct object *obj = (struct object *)ptr;
 297     assert( obj->refcount < INT_MAX );
 298     obj->refcount++;
 299     return obj;
 300 }
 301
 302 /* release an object (i.e. decrement its refcount) */
 303 void release_object( void *ptr )
 304 {
 305     struct object *obj = (struct object *)ptr;
 306     assert( obj->refcount );
 307     if (!--obj->refcount)
 308     {
 309         /* if the refcount is 0, nobody can be in the wait queue */
 310         assert( list_empty( &obj->wait_queue ));
 311         obj->ops->destroy( obj );
 312         if (obj->name) free_name( obj );
 313         free( obj->sd );
 314 #ifdef DEBUG_OBJECTS
 315         list_remove( &obj->obj_list );
 316         memset( obj, 0xaa, obj->ops->size );
 317 #endif
 318         free( obj );
 319     }
 320 }
 321
 322 /* find an object by its name; the refcount is incremented */
 323 struct object *find_object( const struct namespace *namespace, const struct unicode_str *name,
 324                             unsigned int attributes )
 325 {
 326     const struct list *list;
 327     struct list *p;
 328
 329     if (!name || !name->len) return NULL;
 330
 331     list = &namespace->names[ get_name_hash( namespace, name->str, name->len ) ];
 332     LIST_FOR_EACH( p, list )
 333     {
 334         const struct object_name *ptr = LIST_ENTRY( p, struct object_name, entry );
 335         if (ptr->len != name->len) continue;
 336         if (attributes & OBJ_CASE_INSENSITIVE)
 337         {
 338             if (!strncmpiW( ptr->name, name->str, name->len/sizeof(WCHAR) ))
 339                 return grab_object( ptr->obj );
 340         }
 341         else
 342         {
 343             if (!memcmp( ptr->name, name->str, name->len ))
 344                 return grab_object( ptr->obj );
 345         }
 346     }
 347     return NULL;
 348 }
 349
 350 /* find an object by its index; the refcount is incremented */
 351 struct object *find_object_index( const struct namespace *namespace, unsigned int index )
 352 {
 353     unsigned int i;
 354
 355     /* FIXME: not efficient at all */
 356     for (i = 0; i < namespace->hash_size; i++)
 357     {
 358         const struct object_name *ptr;
 359         LIST_FOR_EACH_ENTRY( ptr, &namespace->names[i], const struct object_name, entry )
 360         {
 361             if (!index--) return grab_object( ptr->obj );
 362         }
 363     }
 364     set_error( STATUS_NO_MORE_ENTRIES );
 365     return NULL;
 366 }
 367
 368 /* allocate a namespace */
 369 struct namespace *create_namespace( unsigned int hash_size )
 370 {
 371     struct namespace *namespace;
 372     unsigned int i;
 373
 374     namespace = mem_alloc( sizeof(*namespace) + (hash_size - 1) * sizeof(namespace->names[0]) );
 375     if (namespace)
 376     {
 377         namespace->hash_size      = hash_size;
 378         for (i = 0; i < hash_size; i++) list_init( &namespace->names[i] );
 379     }
 380     return namespace;
 381 }
 382
 383 /* functions for unimplemented/default object operations */
 384
 385 struct object_type *no_get_type( struct object *obj )
 386 {
 387     return NULL;
 388 }
 389
 390 int no_add_queue( struct object *obj, struct wait_queue_entry *entry )
 391 {
 392     set_error( STATUS_OBJECT_TYPE_MISMATCH );
 393     return 0;
 394 }
 395
 396 void no_satisfied( struct object *obj, struct wait_queue_entry *entry )
 397 {
 398 }
 399
 400 int no_signal( struct object *obj, unsigned int access )
 401 {
 402     set_error( STATUS_OBJECT_TYPE_MISMATCH );
 403     return 0;
 404 }
 405
 406 struct fd *no_get_fd( struct object *obj )
 407 {
 408     set_error( STATUS_OBJECT_TYPE_MISMATCH );
 409     return NULL;
 410 }
 411
 412 unsigned int no_map_access( struct object *obj, unsigned int access )
 413 {
 414     if (access & GENERIC_READ)    access |= STANDARD_RIGHTS_READ;
 415     if (access & GENERIC_WRITE)   access |= STANDARD_RIGHTS_WRITE;
 416     if (access & GENERIC_EXECUTE) access |= STANDARD_RIGHTS_EXECUTE;
 417     if (access & GENERIC_ALL)     access |= STANDARD_RIGHTS_ALL;
 418     return access & ~(GENERIC_READ | GENERIC_WRITE | GENERIC_EXECUTE | GENERIC_ALL);
 419 }
 420
 421 struct security_descriptor *default_get_sd( struct object *obj )
 422 {
 423     return obj->sd;
 424 }
 425
 426 int default_set_sd( struct object *obj, const struct security_descriptor *sd,
 427                     unsigned int set_info )
 428 {
 429     struct security_descriptor new_sd, *new_sd_ptr;
 430     int present;
 431     const SID *owner, *group;
 432     const ACL *sacl, *dacl;
 433     char *ptr;
 434
 435     if (!set_info) return 1;
 436
 437     new_sd.control = sd->control & ~SE_SELF_RELATIVE;
 438
 439     if (set_info & OWNER_SECURITY_INFORMATION && sd->owner_len)
 440     {
 441         owner = sd_get_owner( sd );
 442         new_sd.owner_len = sd->owner_len;
 443     }
 444     else if (obj->sd && obj->sd->owner_len)
 445     {
 446         owner = sd_get_owner( obj->sd );
 447         new_sd.owner_len = obj->sd->owner_len;
 448     }
 449     else
 450     {
 451         owner = token_get_user( current->process->token );
 452         new_sd.owner_len = security_sid_len( owner );
 453     }
 454
 455     if (set_info & GROUP_SECURITY_INFORMATION && sd->group_len)
 456     {
 457         group = sd_get_group( sd );
 458         new_sd.group_len = sd->group_len;
 459     }
 460     else if (obj->sd && obj->sd->group_len)
 461     {
 462         group = sd_get_group( obj->sd );
 463         new_sd.group_len = obj->sd->group_len;
 464     }
 465     else
 466     {
 467         group = token_get_primary_group( current->process->token );
 468         new_sd.group_len = security_sid_len( group );
 469     }
 470
 471     new_sd.control |= SE_SACL_PRESENT;
 472     sacl = sd_get_sacl( sd, &present );
 473     if (set_info & SACL_SECURITY_INFORMATION && present)
 474         new_sd.sacl_len = sd->sacl_len;
 475     else
 476     {
 477         if (obj->sd) sacl = sd_get_sacl( obj->sd, &present );
 478
 479         if (obj->sd && present)
 480             new_sd.sacl_len = obj->sd->sacl_len;
 481         else
 482         {
 483             new_sd.sacl_len = 0;
 484         }
 485     }
 486
 487     new_sd.control |= SE_DACL_PRESENT;
 488     dacl = sd_get_dacl( sd, &present );
 489     if (set_info & DACL_SECURITY_INFORMATION && present)
 490         new_sd.dacl_len = sd->dacl_len;
 491     else
 492     {
 493         if (obj->sd) dacl = sd_get_dacl( obj->sd, &present );
 494
 495         if (obj->sd && present)
 496             new_sd.dacl_len = obj->sd->dacl_len;
 497         else
 498         {
 499             dacl = token_get_default_dacl( current->process->token );
 500             new_sd.dacl_len = dacl->AclSize;
 501         }
 502     }
 503
 504     ptr = mem_alloc( sizeof(new_sd) + new_sd.owner_len + new_sd.group_len +
 505                      new_sd.sacl_len + new_sd.dacl_len );
 506     if (!ptr) return 0;
 507     new_sd_ptr = (struct security_descriptor*)ptr;
 508
 509     memcpy( ptr, &new_sd, sizeof(new_sd) );
 510     ptr += sizeof(new_sd);
 511     memcpy( ptr, owner, new_sd.owner_len );
 512     ptr += new_sd.owner_len;
 513     memcpy( ptr, group, new_sd.group_len );
 514     ptr += new_sd.group_len;
 515     memcpy( ptr, sacl, new_sd.sacl_len );
 516     ptr += new_sd.sacl_len;
 517     memcpy( ptr, dacl, new_sd.dacl_len );
 518
 519     free( obj->sd );
 520     obj->sd = new_sd_ptr;
 521     return 1;
 522 }
 523
 524 struct object *no_lookup_name( struct object *obj, struct unicode_str *name,
 525                                unsigned int attr )
 526 {
 527     return NULL;
 528 }
 529
 530 struct object *no_open_file( struct object *obj, unsigned int access, unsigned int sharing,
 531                              unsigned int options )
 532 {
 533     set_error( STATUS_OBJECT_TYPE_MISMATCH );
 534     return NULL;
 535 }
 536
 537 int no_close_handle( struct object *obj, struct process *process, obj_handle_t handle )
 538 {
 539     return 1;  /* ok to close */
 540 }
 541
 542 void no_destroy( struct object *obj )
 543 {
 544 }