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 /* allocate and initialize an object */
 175 void *alloc_object( const struct object_ops *ops )
 176 {
 177     struct object *obj = mem_alloc( ops->size );
 178     if (obj)
 179     {
 180         obj->refcount = 1;
 181         obj->ops      = ops;
 182         obj->name     = NULL;
 183         obj->sd       = NULL;
 184         list_init( &obj->wait_queue );
 185 #ifdef DEBUG_OBJECTS
 186         list_add_head( &object_list, &obj->obj_list );
 187 #endif
 188         return obj;
 189     }
 190     return NULL;
 191 }
 192
 193 void *create_object( struct namespace *namespace, const struct object_ops *ops,
 194                      const struct unicode_str *name, struct object *parent )
 195 {
 196     struct object *obj;
 197     struct object_name *name_ptr;
 198
 199     if (!(name_ptr = alloc_name( name ))) return NULL;
 200     if ((obj = alloc_object( ops )))
 201     {
 202         set_object_name( namespace, obj, name_ptr );
 203         if (parent) name_ptr->parent = grab_object( parent );
 204     }
 205     else
 206         free( name_ptr );
 207     return obj;
 208 }
 209
 210 void *create_named_object( struct namespace *namespace, const struct object_ops *ops,
 211                            const struct unicode_str *name, unsigned int attributes )
 212 {
 213     struct object *obj;
 214
 215     if (!name || !name->len) return alloc_object( ops );
 216
 217     if ((obj = find_object( namespace, name, attributes )))
 218     {
 219         if (attributes & OBJ_OPENIF && obj->ops == ops)
 220             set_error( STATUS_OBJECT_NAME_EXISTS );
 221         else
 222         {
 223             release_object( obj );
 224             obj = NULL;
 225             if (attributes & OBJ_OPENIF)
 226                 set_error( STATUS_OBJECT_TYPE_MISMATCH );
 227             else
 228                 set_error( STATUS_OBJECT_NAME_COLLISION );
 229         }
 230         return obj;
 231     }
 232     if ((obj = create_object( namespace, ops, name, NULL ))) clear_error();
 233     return obj;
 234 }
 235
 236 /* dump the name of an object to stderr */
 237 void dump_object_name( struct object *obj )
 238 {
 239     if (!obj->name) fprintf( stderr, "name=\"\"" );
 240     else
 241     {
 242         fprintf( stderr, "name=L\"" );
 243         dump_strW( obj->name->name, obj->name->len/sizeof(WCHAR), stderr, "\"\"" );
 244         fputc( '\"', stderr );
 245     }
 246 }
 247
 248 /* unlink a named object from its namespace, without freeing the object itself */
 249 void unlink_named_object( struct object *obj )
 250 {
 251     if (obj->name) free_name( obj );
 252     obj->name = NULL;
 253 }
 254
 255 /* mark an object as being stored statically, i.e. only released at shutdown */
 256 void make_object_static( struct object *obj )
 257 {
 258 #ifdef DEBUG_OBJECTS
 259     list_remove( &obj->obj_list );
 260     list_add_head( &static_object_list, &obj->obj_list );
 261 #endif
 262 }
 263
 264 /* grab an object (i.e. increment its refcount) and return the object */
 265 struct object *grab_object( void *ptr )
 266 {
 267     struct object *obj = (struct object *)ptr;
 268     assert( obj->refcount < INT_MAX );
 269     obj->refcount++;
 270     return obj;
 271 }
 272
 273 /* release an object (i.e. decrement its refcount) */
 274 void release_object( void *ptr )
 275 {
 276     struct object *obj = (struct object *)ptr;
 277     assert( obj->refcount );
 278     if (!--obj->refcount)
 279     {
 280         /* if the refcount is 0, nobody can be in the wait queue */
 281         assert( list_empty( &obj->wait_queue ));
 282         obj->ops->destroy( obj );
 283         if (obj->name) free_name( obj );
 284         free( obj->sd );
 285 #ifdef DEBUG_OBJECTS
 286         list_remove( &obj->obj_list );
 287         memset( obj, 0xaa, obj->ops->size );
 288 #endif
 289         free( obj );
 290     }
 291 }
 292
 293 /* find an object by its name; the refcount is incremented */
 294 struct object *find_object( const struct namespace *namespace, const struct unicode_str *name,
 295                             unsigned int attributes )
 296 {
 297     const struct list *list;
 298     struct list *p;
 299
 300     if (!name || !name->len) return NULL;
 301
 302     list = &namespace->names[ get_name_hash( namespace, name->str, name->len ) ];
 303     LIST_FOR_EACH( p, list )
 304     {
 305         const struct object_name *ptr = LIST_ENTRY( p, struct object_name, entry );
 306         if (ptr->len != name->len) continue;
 307         if (attributes & OBJ_CASE_INSENSITIVE)
 308         {
 309             if (!strncmpiW( ptr->name, name->str, name->len/sizeof(WCHAR) ))
 310                 return grab_object( ptr->obj );
 311         }
 312         else
 313         {
 314             if (!memcmp( ptr->name, name->str, name->len ))
 315                 return grab_object( ptr->obj );
 316         }
 317     }
 318     return NULL;
 319 }
 320
 321 /* find an object by its index; the refcount is incremented */
 322 struct object *find_object_index( const struct namespace *namespace, unsigned int index )
 323 {
 324     unsigned int i;
 325
 326     /* FIXME: not efficient at all */
 327     for (i = 0; i < namespace->hash_size; i++)
 328     {
 329         const struct object_name *ptr;
 330         LIST_FOR_EACH_ENTRY( ptr, &namespace->names[i], const struct object_name, entry )
 331         {
 332             if (!index--) return grab_object( ptr->obj );
 333         }
 334     }
 335     set_error( STATUS_NO_MORE_ENTRIES );
 336     return NULL;
 337 }
 338
 339 /* allocate a namespace */
 340 struct namespace *create_namespace( unsigned int hash_size )
 341 {
 342     struct namespace *namespace;
 343     unsigned int i;
 344
 345     namespace = mem_alloc( sizeof(*namespace) + (hash_size - 1) * sizeof(namespace->names[0]) );
 346     if (namespace)
 347     {
 348         namespace->hash_size      = hash_size;
 349         for (i = 0; i < hash_size; i++) list_init( &namespace->names[i] );
 350     }
 351     return namespace;
 352 }
 353
 354 /* functions for unimplemented/default object operations */
 355
 356 struct object_type *no_get_type( struct object *obj )
 357 {
 358     return NULL;
 359 }
 360
 361 int no_add_queue( struct object *obj, struct wait_queue_entry *entry )
 362 {
 363     set_error( STATUS_OBJECT_TYPE_MISMATCH );
 364     return 0;
 365 }
 366
 367 int no_satisfied( struct object *obj, struct thread *thread )
 368 {
 369     return 0;  /* not abandoned */
 370 }
 371
 372 int no_signal( struct object *obj, unsigned int access )
 373 {
 374     set_error( STATUS_OBJECT_TYPE_MISMATCH );
 375     return 0;
 376 }
 377
 378 struct fd *no_get_fd( struct object *obj )
 379 {
 380     set_error( STATUS_OBJECT_TYPE_MISMATCH );
 381     return NULL;
 382 }
 383
 384 unsigned int no_map_access( struct object *obj, unsigned int access )
 385 {
 386     if (access & GENERIC_READ)    access |= STANDARD_RIGHTS_READ;
 387     if (access & GENERIC_WRITE)   access |= STANDARD_RIGHTS_WRITE;
 388     if (access & GENERIC_EXECUTE) access |= STANDARD_RIGHTS_EXECUTE;
 389     if (access & GENERIC_ALL)     access |= STANDARD_RIGHTS_ALL;
 390     return access & ~(GENERIC_READ | GENERIC_WRITE | GENERIC_EXECUTE | GENERIC_ALL);
 391 }
 392
 393 struct security_descriptor *default_get_sd( struct object *obj )
 394 {
 395     return obj->sd;
 396 }
 397
 398 int default_set_sd( struct object *obj, const struct security_descriptor *sd,
 399                     unsigned int set_info )
 400 {
 401     struct security_descriptor new_sd, *new_sd_ptr;
 402     int present;
 403     const SID *owner, *group;
 404     const ACL *sacl, *dacl;
 405     char *ptr;
 406
 407     if (!set_info) return 1;
 408
 409     new_sd.control = sd->control & ~SE_SELF_RELATIVE;
 410
 411     owner = sd_get_owner( sd );
 412     if (set_info & OWNER_SECURITY_INFORMATION && owner)
 413         new_sd.owner_len = sd->owner_len;
 414     else
 415     {
 416         owner = token_get_user( current->process->token );
 417         new_sd.owner_len = FIELD_OFFSET(SID, SubAuthority[owner->SubAuthorityCount]);
 418         new_sd.control |= SE_OWNER_DEFAULTED;
 419     }
 420
 421     group = sd_get_group( sd );
 422     if (set_info & GROUP_SECURITY_INFORMATION && group)
 423         new_sd.group_len = sd->group_len;
 424     else
 425     {
 426         group = token_get_primary_group( current->process->token );
 427         new_sd.group_len = FIELD_OFFSET(SID, SubAuthority[group->SubAuthorityCount]);
 428         new_sd.control |= SE_GROUP_DEFAULTED;
 429     }
 430
 431     new_sd.control |= SE_SACL_PRESENT;
 432     sacl = sd_get_sacl( sd, &present );
 433     if (set_info & SACL_SECURITY_INFORMATION && present)
 434         new_sd.sacl_len = sd->sacl_len;
 435     else
 436     {
 437         if (obj->sd) sacl = sd_get_sacl( obj->sd, &present );
 438
 439         if (obj->sd && present)
 440             new_sd.sacl_len = obj->sd->sacl_len;
 441         else
 442         {
 443             new_sd.sacl_len = 0;
 444             new_sd.control |= SE_SACL_DEFAULTED;
 445         }
 446     }
 447
 448     new_sd.control |= SE_DACL_PRESENT;
 449     dacl = sd_get_dacl( sd, &present );
 450     if (set_info & DACL_SECURITY_INFORMATION && present)
 451         new_sd.dacl_len = sd->dacl_len;
 452     else
 453     {
 454         if (obj->sd) dacl = sd_get_dacl( obj->sd, &present );
 455
 456         if (obj->sd && present)
 457             new_sd.dacl_len = obj->sd->dacl_len;
 458         else
 459         {
 460             dacl = token_get_default_dacl( current->process->token );
 461             new_sd.dacl_len = dacl->AclSize;
 462             new_sd.control |= SE_DACL_DEFAULTED;
 463         }
 464     }
 465
 466     ptr = mem_alloc( sizeof(new_sd) + new_sd.owner_len + new_sd.group_len +
 467                      new_sd.sacl_len + new_sd.dacl_len );
 468     if (!ptr) return 0;
 469     new_sd_ptr = (struct security_descriptor*)ptr;
 470
 471     memcpy( ptr, &new_sd, sizeof(new_sd) );
 472     ptr += sizeof(new_sd);
 473     memcpy( ptr, owner, new_sd.owner_len );
 474     ptr += new_sd.owner_len;
 475     memcpy( ptr, group, new_sd.group_len );
 476     ptr += new_sd.group_len;
 477     memcpy( ptr, sacl, new_sd.sacl_len );
 478     ptr += new_sd.sacl_len;
 479     memcpy( ptr, dacl, new_sd.dacl_len );
 480
 481     free( obj->sd );
 482     obj->sd = new_sd_ptr;
 483     return 1;
 484 }
 485
 486 struct object *no_lookup_name( struct object *obj, struct unicode_str *name,
 487                                unsigned int attr )
 488 {
 489     return NULL;
 490 }
 491
 492 struct object *no_open_file( struct object *obj, unsigned int access, unsigned int sharing,
 493                              unsigned int options )
 494 {
 495     set_error( STATUS_OBJECT_TYPE_MISMATCH );
 496     return NULL;
 497 }
 498
 499 int no_close_handle( struct object *obj, struct process *process, obj_handle_t handle )
 500 {
 501     return 1;  /* ok to close */
 502 }
 503
 504 void no_destroy( struct object *obj )
 505 {
 506 }