server/file.c

   1 /*
   2  * Server-side file 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 <fcntl.h>
  26 #include <stdarg.h>
  27 #include <stdio.h>
  28 #include <string.h>
  29 #include <stdlib.h>
  30 #include <errno.h>
  31 #ifdef HAVE_SYS_ERRNO_H
  32 #include <sys/errno.h>
  33 #endif
  34 #include <sys/stat.h>
  35 #include <sys/time.h>
  36 #include <sys/types.h>
  37 #include <time.h>
  38 #include <unistd.h>
  39 #ifdef HAVE_UTIME_H
  40 #include <utime.h>
  41 #endif
  42 #ifdef HAVE_POLL_H
  43 #include <poll.h>
  44 #endif
  45
  46 #include "ntstatus.h"
  47 #define WIN32_NO_STATUS
  48 #include "windef.h"
  49 #include "winternl.h"
  50
  51 #include "file.h"
  52 #include "handle.h"
  53 #include "thread.h"
  54 #include "request.h"
  55 #include "process.h"
  56 #include "security.h"
  57
  58 struct file
  59 {
  60     struct object       obj;        /* object header */
  61     struct fd          *fd;         /* file descriptor for this file */
  62     unsigned int        access;     /* file access (FILE_READ_DATA etc.) */
  63     mode_t              mode;       /* file stat.st_mode */
  64     uid_t               uid;        /* file stat.st_uid */
  65 };
  66
  67 static unsigned int generic_file_map_access( unsigned int access );
  68
  69 static void file_dump( struct object *obj, int verbose );
  70 static struct fd *file_get_fd( struct object *obj );
  71 static struct security_descriptor *file_get_sd( struct object *obj );
  72 static int file_set_sd( struct object *obj, const struct security_descriptor *sd, unsigned int set_info );
  73 static void file_destroy( struct object *obj );
  74
  75 static int file_get_poll_events( struct fd *fd );
  76 static void file_flush( struct fd *fd, struct event **event );
  77 static enum server_fd_type file_get_fd_type( struct fd *fd );
  78
  79 static const struct object_ops file_ops =
  80 {
  81     sizeof(struct file),          /* size */
  82     file_dump,                    /* dump */
  83     no_get_type,                  /* get_type */
  84     add_queue,                    /* add_queue */
  85     remove_queue,                 /* remove_queue */
  86     default_fd_signaled,          /* signaled */
  87     no_satisfied,                 /* satisfied */
  88     no_signal,                    /* signal */
  89     file_get_fd,                  /* get_fd */
  90     default_fd_map_access,        /* map_access */
  91     file_get_sd,                  /* get_sd */
  92     file_set_sd,                  /* set_sd */
  93     no_lookup_name,               /* lookup_name */
  94     no_open_file,                 /* open_file */
  95     fd_close_handle,              /* close_handle */
  96     file_destroy                  /* destroy */
  97 };
  98
  99 static const struct fd_ops file_fd_ops =
 100 {
 101     file_get_poll_events,         /* get_poll_events */
 102     default_poll_event,           /* poll_event */
 103     file_flush,                   /* flush */
 104     file_get_fd_type,             /* get_fd_type */
 105     default_fd_ioctl,             /* ioctl */
 106     default_fd_queue_async,       /* queue_async */
 107     default_fd_reselect_async,    /* reselect_async */
 108     default_fd_cancel_async       /* cancel_async */
 109 };
 110
 111 static inline int is_overlapped( const struct file *file )
 112 {
 113     return !(get_fd_options( file->fd ) & (FILE_SYNCHRONOUS_IO_ALERT | FILE_SYNCHRONOUS_IO_NONALERT));
 114 }
 115
 116 /* create a file from a file descriptor */
 117 /* if the function fails the fd is closed */
 118 struct file *create_file_for_fd( int fd, unsigned int access, unsigned int sharing )
 119 {
 120     struct file *file;
 121     struct stat st;
 122
 123     if (fstat( fd, &st ) == -1)
 124     {
 125         file_set_error();
 126         return NULL;
 127     }
 128
 129     if ((file = alloc_object( &file_ops )))
 130     {
 131         file->mode = st.st_mode;
 132         file->access = default_fd_map_access( &file->obj, access );
 133         if (!(file->fd = create_anonymous_fd( &file_fd_ops, fd, &file->obj,
 134                                               FILE_SYNCHRONOUS_IO_NONALERT )))
 135         {
 136             release_object( file );
 137             return NULL;
 138         }
 139         allow_fd_caching( file->fd );
 140     }
 141     return file;
 142 }
 143
 144 /* create a file by duplicating an fd object */
 145 struct file *create_file_for_fd_obj( struct fd *fd, unsigned int access, unsigned int sharing )
 146 {
 147     struct file *file;
 148     struct stat st;
 149
 150     if (fstat( get_unix_fd(fd), &st ) == -1)
 151     {
 152         file_set_error();
 153         return NULL;
 154     }
 155
 156     if ((file = alloc_object( &file_ops )))
 157     {
 158         file->mode = st.st_mode;
 159         file->access = default_fd_map_access( &file->obj, access );
 160         if (!(file->fd = dup_fd_object( fd, access, sharing, FILE_SYNCHRONOUS_IO_NONALERT )))
 161         {
 162             release_object( file );
 163             return NULL;
 164         }
 165         set_fd_user( file->fd, &file_fd_ops, &file->obj );
 166     }
 167     return file;
 168 }
 169
 170 static struct object *create_file_obj( struct fd *fd, unsigned int access, mode_t mode )
 171 {
 172     struct file *file = alloc_object( &file_ops );
 173
 174     if (!file) return NULL;
 175     file->access  = access;
 176     file->mode    = mode;
 177     file->uid     = ~(uid_t)0;
 178     file->fd      = fd;
 179     grab_object( fd );
 180     set_fd_user( fd, &file_fd_ops, &file->obj );
 181     return &file->obj;
 182 }
 183
 184 static struct object *create_file( struct fd *root, const char *nameptr, data_size_t len,
 185                                    unsigned int access, unsigned int sharing, int create,
 186                                    unsigned int options, unsigned int attrs,
 187                                    const struct security_descriptor *sd )
 188 {
 189     struct object *obj = NULL;
 190     struct fd *fd;
 191     int flags;
 192     char *name;
 193     mode_t mode;
 194
 195     if (!len || ((nameptr[0] == '/') ^ !root))
 196     {
 197         set_error( STATUS_OBJECT_PATH_SYNTAX_BAD );
 198         return NULL;
 199     }
 200     if (!(name = mem_alloc( len + 1 ))) return NULL;
 201     memcpy( name, nameptr, len );
 202     name[len] = 0;
 203
 204     switch(create)
 205     {
 206     case FILE_CREATE:       flags = O_CREAT | O_EXCL; break;
 207     case FILE_OVERWRITE_IF: /* FIXME: the difference is whether we trash existing attr or not */
 208                             access |= FILE_WRITE_ATTRIBUTES;
 209     case FILE_SUPERSEDE:    flags = O_CREAT | O_TRUNC; break;
 210     case FILE_OPEN:         flags = 0; break;
 211     case FILE_OPEN_IF:      flags = O_CREAT; break;
 212     case FILE_OVERWRITE:    flags = O_TRUNC;
 213                             access |= FILE_WRITE_ATTRIBUTES; break;
 214     default:                set_error( STATUS_INVALID_PARAMETER ); goto done;
 215     }
 216
 217     if (sd)
 218     {
 219         const SID *owner = sd_get_owner( sd );
 220         if (!owner)
 221             owner = token_get_user( current->process->token );
 222         mode = sd_to_mode( sd, owner );
 223     }
 224     else
 225         mode = (attrs & FILE_ATTRIBUTE_READONLY) ? 0444 : 0666;
 226
 227     if (len >= 4 &&
 228         (!strcasecmp( name + len - 4, ".exe" ) || !strcasecmp( name + len - 4, ".com" )))
 229     {
 230         if (mode & S_IRUSR)
 231             mode |= S_IXUSR;
 232         if (mode & S_IRGRP)
 233             mode |= S_IXGRP;
 234         if (mode & S_IROTH)
 235             mode |= S_IXOTH;
 236     }
 237
 238     access = generic_file_map_access( access );
 239
 240     /* FIXME: should set error to STATUS_OBJECT_NAME_COLLISION if file existed before */
 241     fd = open_fd( root, name, flags | O_NONBLOCK | O_LARGEFILE, &mode, access, sharing, options );
 242     if (!fd) goto done;
 243
 244     if (S_ISDIR(mode))
 245         obj = create_dir_obj( fd, access, mode );
 246     else if (S_ISCHR(mode) && is_serial_fd( fd ))
 247         obj = create_serial( fd );
 248     else
 249         obj = create_file_obj( fd, access, mode );
 250
 251     release_object( fd );
 252
 253 done:
 254     free( name );
 255     return obj;
 256 }
 257
 258 /* check if two file objects point to the same file */
 259 int is_same_file( struct file *file1, struct file *file2 )
 260 {
 261     return is_same_file_fd( file1->fd, file2->fd );
 262 }
 263
 264 static void file_dump( struct object *obj, int verbose )
 265 {
 266     struct file *file = (struct file *)obj;
 267     assert( obj->ops == &file_ops );
 268     fprintf( stderr, "File fd=%p\n", file->fd );
 269 }
 270
 271 static int file_get_poll_events( struct fd *fd )
 272 {
 273     struct file *file = get_fd_user( fd );
 274     int events = 0;
 275     assert( file->obj.ops == &file_ops );
 276     if (file->access & FILE_UNIX_READ_ACCESS) events |= POLLIN;
 277     if (file->access & FILE_UNIX_WRITE_ACCESS) events |= POLLOUT;
 278     return events;
 279 }
 280
 281 static void file_flush( struct fd *fd, struct event **event )
 282 {
 283     int unix_fd = get_unix_fd( fd );
 284     if (unix_fd != -1 && fsync( unix_fd ) == -1) file_set_error();
 285 }
 286
 287 static enum server_fd_type file_get_fd_type( struct fd *fd )
 288 {
 289     struct file *file = get_fd_user( fd );
 290
 291     if (S_ISREG(file->mode) || S_ISBLK(file->mode)) return FD_TYPE_FILE;
 292     if (S_ISDIR(file->mode)) return FD_TYPE_DIR;
 293     return FD_TYPE_CHAR;
 294 }
 295
 296 static struct fd *file_get_fd( struct object *obj )
 297 {
 298     struct file *file = (struct file *)obj;
 299     assert( obj->ops == &file_ops );
 300     return (struct fd *)grab_object( file->fd );
 301 }
 302
 303 static unsigned int generic_file_map_access( unsigned int access )
 304 {
 305     if (access & GENERIC_READ)    access |= FILE_GENERIC_READ;
 306     if (access & GENERIC_WRITE)   access |= FILE_GENERIC_WRITE;
 307     if (access & GENERIC_EXECUTE) access |= FILE_GENERIC_EXECUTE;
 308     if (access & GENERIC_ALL)     access |= FILE_ALL_ACCESS;
 309     return access & ~(GENERIC_READ | GENERIC_WRITE | GENERIC_EXECUTE | GENERIC_ALL);
 310 }
 311
 312 struct security_descriptor *mode_to_sd( mode_t mode, const SID *user, const SID *group )
 313 {
 314     struct security_descriptor *sd;
 315     size_t dacl_size;
 316     ACE_HEADER *current_ace;
 317     ACCESS_ALLOWED_ACE *aaa;
 318     ACL *dacl;
 319     SID *sid;
 320     char *ptr;
 321     const SID *world_sid = security_world_sid;
 322     const SID *local_system_sid = security_local_system_sid;
 323
 324     dacl_size = sizeof(ACL) + FIELD_OFFSET(ACCESS_ALLOWED_ACE, SidStart) +
 325         FIELD_OFFSET(SID, SubAuthority[local_system_sid->SubAuthorityCount]);
 326     if (mode & S_IRWXU)
 327         dacl_size += FIELD_OFFSET(ACCESS_ALLOWED_ACE, SidStart) +
 328             FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]);
 329     if ((!(mode & S_IRUSR) && (mode & (S_IRGRP|S_IROTH))) ||
 330         (!(mode & S_IWUSR) && (mode & (S_IWGRP|S_IWOTH))) ||
 331         (!(mode & S_IXUSR) && (mode & (S_IXGRP|S_IXOTH))))
 332         dacl_size += FIELD_OFFSET(ACCESS_DENIED_ACE, SidStart) +
 333             FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]);
 334     if (mode & S_IRWXO)
 335         dacl_size += FIELD_OFFSET(ACCESS_ALLOWED_ACE, SidStart) +
 336             FIELD_OFFSET(SID, SubAuthority[world_sid->SubAuthorityCount]);
 337
 338     sd = mem_alloc( sizeof(struct security_descriptor) +
 339                     FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]) +
 340                     FIELD_OFFSET(SID, SubAuthority[group->SubAuthorityCount]) +
 341                     dacl_size );
 342     if (!sd) return sd;
 343
 344     sd->control = SE_DACL_PRESENT;
 345     sd->owner_len = FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]);
 346     sd->group_len = FIELD_OFFSET(SID, SubAuthority[group->SubAuthorityCount]);
 347     sd->sacl_len = 0;
 348     sd->dacl_len = dacl_size;
 349
 350     ptr = (char *)(sd + 1);
 351     memcpy( ptr, user, sd->owner_len );
 352     ptr += sd->owner_len;
 353     memcpy( ptr, group, sd->group_len );
 354     ptr += sd->group_len;
 355
 356     dacl = (ACL *)ptr;
 357     dacl->AclRevision = ACL_REVISION;
 358     dacl->Sbz1 = 0;
 359     dacl->AclSize = dacl_size;
 360     dacl->AceCount = 1 + (mode & S_IRWXU ? 1 : 0) + (mode & S_IRWXO ? 1 : 0);
 361     if ((!(mode & S_IRUSR) && (mode & (S_IRGRP|S_IROTH))) ||
 362         (!(mode & S_IWUSR) && (mode & (S_IWGRP|S_IWOTH))) ||
 363         (!(mode & S_IXUSR) && (mode & (S_IXGRP|S_IXOTH))))
 364         dacl->AceCount++;
 365     dacl->Sbz2 = 0;
 366
 367     /* always give FILE_ALL_ACCESS for Local System */
 368     aaa = (ACCESS_ALLOWED_ACE *)(dacl + 1);
 369     current_ace = &aaa->Header;
 370     aaa->Header.AceType = ACCESS_ALLOWED_ACE_TYPE;
 371     aaa->Header.AceFlags = 0;
 372     aaa->Header.AceSize = FIELD_OFFSET(ACCESS_ALLOWED_ACE, SidStart) +
 373         FIELD_OFFSET(SID, SubAuthority[local_system_sid->SubAuthorityCount]);
 374     aaa->Mask = FILE_ALL_ACCESS;
 375     sid = (SID *)&aaa->SidStart;
 376     memcpy( sid, local_system_sid, FIELD_OFFSET(SID, SubAuthority[local_system_sid->SubAuthorityCount]) );
 377
 378     if (mode & S_IRWXU)
 379     {
 380         /* appropriate access rights for the user */
 381         aaa = (ACCESS_ALLOWED_ACE *)ace_next( current_ace );
 382         current_ace = &aaa->Header;
 383         aaa->Header.AceType = ACCESS_ALLOWED_ACE_TYPE;
 384         aaa->Header.AceFlags = 0;
 385         aaa->Header.AceSize = FIELD_OFFSET(ACCESS_ALLOWED_ACE, SidStart) +
 386                               FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]);
 387         aaa->Mask = WRITE_DAC | WRITE_OWNER;
 388         if (mode & S_IRUSR)
 389             aaa->Mask |= FILE_GENERIC_READ | FILE_GENERIC_EXECUTE;
 390         if (mode & S_IWUSR)
 391             aaa->Mask |= FILE_GENERIC_WRITE | DELETE | FILE_DELETE_CHILD;
 392         sid = (SID *)&aaa->SidStart;
 393         memcpy( sid, user, FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]) );
 394     }
 395     if ((!(mode & S_IRUSR) && (mode & (S_IRGRP|S_IROTH))) ||
 396         (!(mode & S_IWUSR) && (mode & (S_IWGRP|S_IWOTH))) ||
 397         (!(mode & S_IXUSR) && (mode & (S_IXGRP|S_IXOTH))))
 398     {
 399         /* deny just in case the user is a member of the group */
 400         ACCESS_DENIED_ACE *ada = (ACCESS_DENIED_ACE *)ace_next( current_ace );
 401         current_ace = &ada->Header;
 402         ada->Header.AceType = ACCESS_DENIED_ACE_TYPE;
 403         ada->Header.AceFlags = 0;
 404         ada->Header.AceSize = FIELD_OFFSET(ACCESS_DENIED_ACE, SidStart) +
 405                               FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]);
 406         ada->Mask = 0;
 407         if (!(mode & S_IRUSR) && (mode & (S_IRGRP|S_IROTH)))
 408             ada->Mask |= FILE_GENERIC_READ | FILE_GENERIC_EXECUTE;
 409         if (!(mode & S_IWUSR) && (mode & (S_IWGRP|S_IROTH)))
 410             ada->Mask |= FILE_GENERIC_WRITE | DELETE | FILE_DELETE_CHILD;
 411         ada->Mask &= ~STANDARD_RIGHTS_ALL; /* never deny standard rights */
 412         sid = (SID *)&ada->SidStart;
 413         memcpy( sid, user, FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]) );
 414     }
 415     if (mode & S_IRWXO)
 416     {
 417         /* appropriate access rights for Everyone */
 418         aaa = (ACCESS_ALLOWED_ACE *)ace_next( current_ace );
 419         current_ace = &aaa->Header;
 420         aaa->Header.AceType = ACCESS_ALLOWED_ACE_TYPE;
 421         aaa->Header.AceFlags = 0;
 422         aaa->Header.AceSize = FIELD_OFFSET(ACCESS_ALLOWED_ACE, SidStart) +
 423                              FIELD_OFFSET(SID, SubAuthority[world_sid->SubAuthorityCount]);
 424         aaa->Mask = 0;
 425         if (mode & S_IROTH)
 426             aaa->Mask |= FILE_GENERIC_READ | FILE_GENERIC_EXECUTE;
 427         if (mode & S_IWOTH)
 428             aaa->Mask |= FILE_GENERIC_WRITE | DELETE | FILE_DELETE_CHILD;
 429         sid = (SID *)&aaa->SidStart;
 430         memcpy( sid, world_sid, FIELD_OFFSET(SID, SubAuthority[world_sid->SubAuthorityCount]) );
 431     }
 432
 433     return sd;
 434 }
 435
 436 static struct security_descriptor *file_get_sd( struct object *obj )
 437 {
 438     struct file *file = (struct file *)obj;
 439     struct stat st;
 440     int unix_fd;
 441     struct security_descriptor *sd;
 442
 443     assert( obj->ops == &file_ops );
 444
 445     unix_fd = get_file_unix_fd( file );
 446
 447     if (unix_fd == -1 || fstat( unix_fd, &st ) == -1)
 448         return obj->sd;
 449
 450     /* mode and uid the same? if so, no need to re-generate security descriptor */
 451     if (obj->sd && (st.st_mode & (S_IRWXU|S_IRWXO)) == (file->mode & (S_IRWXU|S_IRWXO)) &&
 452         (st.st_uid == file->uid))
 453         return obj->sd;
 454
 455     sd = mode_to_sd( st.st_mode,
 456                      security_unix_uid_to_sid( st.st_uid ),
 457                      token_get_primary_group( current->process->token ));
 458     if (!sd) return obj->sd;
 459
 460     file->mode = st.st_mode;
 461     file->uid = st.st_uid;
 462     free( obj->sd );
 463     obj->sd = sd;
 464     return sd;
 465 }
 466
 467 static mode_t file_access_to_mode( unsigned int access )
 468 {
 469     mode_t mode = 0;
 470
 471     access = generic_file_map_access( access );
 472     if (access & FILE_READ_DATA)  mode |= 4;
 473     if (access & FILE_WRITE_DATA) mode |= 2;
 474     if (access & FILE_EXECUTE)    mode |= 1;
 475     return mode;
 476 }
 477
 478 mode_t sd_to_mode( const struct security_descriptor *sd, const SID *owner )
 479 {
 480     mode_t new_mode = 0;
 481     mode_t denied_mode = 0;
 482     mode_t mode;
 483     int present;
 484     const ACL *dacl = sd_get_dacl( sd, &present );
 485     const SID *user = token_get_user( current->process->token );
 486     if (present && dacl)
 487     {
 488         const ACE_HEADER *ace = (const ACE_HEADER *)(dacl + 1);
 489         ULONG i;
 490         for (i = 0; i < dacl->AceCount; i++, ace = ace_next( ace ))
 491         {
 492             const ACCESS_ALLOWED_ACE *aa_ace;
 493             const ACCESS_DENIED_ACE *ad_ace;
 494             const SID *sid;
 495
 496             if (ace->AceFlags & INHERIT_ONLY_ACE) continue;
 497
 498             switch (ace->AceType)
 499             {
 500                 case ACCESS_DENIED_ACE_TYPE:
 501                     ad_ace = (const ACCESS_DENIED_ACE *)ace;
 502                     sid = (const SID *)&ad_ace->SidStart;
 503                     mode = file_access_to_mode( ad_ace->Mask );
 504                     if (security_equal_sid( sid, security_world_sid ))
 505                     {
 506                         denied_mode |= (mode << 6) | (mode << 3) | mode; /* all */
 507                     }
 508                     else if (security_equal_sid( sid, owner ))
 509                     {
 510                         denied_mode |= (mode << 6);  /* user only */
 511                     }
 512                     else if ((security_equal_sid( user, owner ) &&
 513                               token_sid_present( current->process->token, sid, TRUE )))
 514                     {
 515                         denied_mode |= (mode << 6) | (mode << 3);  /* user + group */
 516                     }
 517                     break;
 518                 case ACCESS_ALLOWED_ACE_TYPE:
 519                     aa_ace = (const ACCESS_ALLOWED_ACE *)ace;
 520                     sid = (const SID *)&aa_ace->SidStart;
 521                     mode = file_access_to_mode( aa_ace->Mask );
 522                     if (security_equal_sid( sid, security_world_sid ))
 523                     {
 524                         new_mode |= (mode << 6) | (mode << 3) | mode;  /* all */
 525                     }
 526                     else if (security_equal_sid( sid, owner ))
 527                     {
 528                         new_mode |= (mode << 6);  /* user only */
 529                     }
 530                     else if ((security_equal_sid( user, owner ) &&
 531                               token_sid_present( current->process->token, sid, FALSE )))
 532                     {
 533                         new_mode |= (mode << 6) | (mode << 3);  /* user + group */
 534                     }
 535                     break;
 536             }
 537         }
 538     }
 539     else
 540         /* no ACL means full access rights to anyone */
 541         new_mode = S_IRWXU | S_IRWXG | S_IRWXO;
 542
 543     return new_mode & ~denied_mode;
 544 }
 545
 546 static int file_set_sd( struct object *obj, const struct security_descriptor *sd,
 547                         unsigned int set_info )
 548 {
 549     struct file *file = (struct file *)obj;
 550     const SID *owner;
 551     struct stat st;
 552     mode_t mode;
 553     int unix_fd;
 554
 555     assert( obj->ops == &file_ops );
 556
 557     unix_fd = get_file_unix_fd( file );
 558
 559     if (unix_fd == -1 || fstat( unix_fd, &st ) == -1) return 1;
 560
 561     if (set_info & OWNER_SECURITY_INFORMATION)
 562     {
 563         owner = sd_get_owner( sd );
 564         if (!owner)
 565         {
 566             set_error( STATUS_INVALID_SECURITY_DESCR );
 567             return 0;
 568         }
 569         if (!obj->sd || !security_equal_sid( owner, sd_get_owner( obj->sd ) ))
 570         {
 571             /* FIXME: get Unix uid and call fchown */
 572         }
 573     }
 574     else if (obj->sd)
 575         owner = sd_get_owner( obj->sd );
 576     else
 577         owner = token_get_user( current->process->token );
 578
 579     /* group and sacl not supported */
 580
 581     if (set_info & DACL_SECURITY_INFORMATION)
 582     {
 583         /* keep the bits that we don't map to access rights in the ACL */
 584         mode = st.st_mode & (S_ISUID|S_ISGID|S_ISVTX);
 585         mode |= sd_to_mode( sd, owner );
 586
 587         if (((st.st_mode ^ mode) & (S_IRWXU|S_IRWXG|S_IRWXO)) && fchmod( unix_fd, mode ) == -1)
 588         {
 589             file_set_error();
 590             return 0;
 591         }
 592     }
 593     return 1;
 594 }
 595
 596 static void file_destroy( struct object *obj )
 597 {
 598     struct file *file = (struct file *)obj;
 599     assert( obj->ops == &file_ops );
 600
 601     if (file->fd) release_object( file->fd );
 602 }
 603
 604 /* set the last error depending on errno */
 605 void file_set_error(void)
 606 {
 607     switch (errno)
 608     {
 609     case ETXTBSY:
 610     case EAGAIN:    set_error( STATUS_SHARING_VIOLATION ); break;
 611     case EBADF:     set_error( STATUS_INVALID_HANDLE ); break;
 612     case ENOSPC:    set_error( STATUS_DISK_FULL ); break;
 613     case EACCES:
 614     case ESRCH:
 615     case EROFS:
 616     case EPERM:     set_error( STATUS_ACCESS_DENIED ); break;
 617     case EBUSY:     set_error( STATUS_FILE_LOCK_CONFLICT ); break;
 618     case ENOENT:    set_error( STATUS_NO_SUCH_FILE ); break;
 619     case EISDIR:    set_error( STATUS_FILE_IS_A_DIRECTORY ); break;
 620     case ENFILE:
 621     case EMFILE:    set_error( STATUS_TOO_MANY_OPENED_FILES ); break;
 622     case EEXIST:    set_error( STATUS_OBJECT_NAME_COLLISION ); break;
 623     case EINVAL:    set_error( STATUS_INVALID_PARAMETER ); break;
 624     case ESPIPE:    set_error( STATUS_ILLEGAL_FUNCTION ); break;
 625     case ENOTEMPTY: set_error( STATUS_DIRECTORY_NOT_EMPTY ); break;
 626     case EIO:       set_error( STATUS_ACCESS_VIOLATION ); break;
 627     case ENOTDIR:   set_error( STATUS_NOT_A_DIRECTORY ); break;
 628     case EFBIG:     set_error( STATUS_SECTION_TOO_BIG ); break;
 629     case ENODEV:    set_error( STATUS_NO_SUCH_DEVICE ); break;
 630     case ENXIO:     set_error( STATUS_NO_SUCH_DEVICE ); break;
 631 #ifdef EOVERFLOW
 632     case EOVERFLOW: set_error( STATUS_INVALID_PARAMETER ); break;
 633 #endif
 634     default:
 635         perror("wineserver: file_set_error() can't map error");
 636         set_error( STATUS_UNSUCCESSFUL );
 637         break;
 638     }
 639 }
 640
 641 struct file *get_file_obj( struct process *process, obj_handle_t handle, unsigned int access )
 642 {
 643     return (struct file *)get_handle_obj( process, handle, access, &file_ops );
 644 }
 645
 646 int get_file_unix_fd( struct file *file )
 647 {
 648     return get_unix_fd( file->fd );
 649 }
 650
 651 /* create a file */
 652 DECL_HANDLER(create_file)
 653 {
 654     struct object *file;
 655     struct fd *root_fd = NULL;
 656     const struct object_attributes *objattr = get_req_data();
 657     const struct security_descriptor *sd;
 658     const char *name;
 659     data_size_t name_len;
 660
 661     reply->handle = 0;
 662
 663     if (!objattr_is_valid( objattr, get_req_data_size() ))
 664         return;
 665     /* name is transferred in the unix codepage outside of the objattr structure */
 666     if (objattr->name_len)
 667     {
 668         set_error( STATUS_INVALID_PARAMETER );
 669         return;
 670     }
 671
 672     if (objattr->rootdir)
 673     {
 674         struct dir *root;
 675
 676         if (!(root = get_dir_obj( current->process, objattr->rootdir, 0 ))) return;
 677         root_fd = get_obj_fd( (struct object *)root );
 678         release_object( root );
 679         if (!root_fd) return;
 680     }
 681
 682     sd = objattr->sd_len ? (const struct security_descriptor *)(objattr + 1) : NULL;
 683
 684     name = (const char *)get_req_data() + sizeof(*objattr) + objattr->sd_len;
 685     name_len = get_req_data_size() - sizeof(*objattr) - objattr->sd_len;
 686
 687     reply->handle = 0;
 688     if ((file = create_file( root_fd, name, name_len, req->access, req->sharing,
 689                              req->create, req->options, req->attrs, sd )))
 690     {
 691         reply->handle = alloc_handle( current->process, file, req->access, req->attributes );
 692         release_object( file );
 693     }
 694     if (root_fd) release_object( root_fd );
 695 }
 696
 697 /* allocate a file handle for a Unix fd */
 698 DECL_HANDLER(alloc_file_handle)
 699 {
 700     struct file *file;
 701     int fd;
 702
 703     reply->handle = 0;
 704     if ((fd = thread_get_inflight_fd( current, req->fd )) == -1)
 705     {
 706         set_error( STATUS_INVALID_HANDLE );
 707         return;
 708     }
 709     if ((file = create_file_for_fd( fd, req->access, FILE_SHARE_READ | FILE_SHARE_WRITE )))
 710     {
 711         reply->handle = alloc_handle( current->process, file, req->access, req->attributes );
 712         release_object( file );
 713     }
 714 }
 715
 716 /* lock a region of a file */
 717 DECL_HANDLER(lock_file)
 718 {
 719     struct file *file;
 720
 721     if ((file = get_file_obj( current->process, req->handle, 0 )))
 722     {
 723         reply->handle = lock_fd( file->fd, req->offset, req->count, req->shared, req->wait );
 724         reply->overlapped = is_overlapped( file );
 725         release_object( file );
 726     }
 727 }
 728
 729 /* unlock a region of a file */
 730 DECL_HANDLER(unlock_file)
 731 {
 732     struct file *file;
 733
 734     if ((file = get_file_obj( current->process, req->handle, 0 )))
 735     {
 736         unlock_fd( file->fd, req->offset, req->count );
 737         release_object( file );
 738     }
 739 }