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 static mode_t sd_to_mode( const struct security_descriptor *sd, const SID *owner );
  79
  80 static const struct object_ops file_ops =
  81 {
  82     sizeof(struct file),          /* size */
  83     file_dump,                    /* dump */
  84     no_get_type,                  /* get_type */
  85     add_queue,                    /* add_queue */
  86     remove_queue,                 /* remove_queue */
  87     default_fd_signaled,          /* signaled */
  88     no_satisfied,                 /* satisfied */
  89     no_signal,                    /* signal */
  90     file_get_fd,                  /* get_fd */
  91     default_fd_map_access,        /* map_access */
  92     file_get_sd,                  /* get_sd */
  93     file_set_sd,                  /* set_sd */
  94     no_lookup_name,               /* lookup_name */
  95     no_open_file,                 /* open_file */
  96     fd_close_handle,              /* close_handle */
  97     file_destroy                  /* destroy */
  98 };
  99
 100 static const struct fd_ops file_fd_ops =
 101 {
 102     file_get_poll_events,         /* get_poll_events */
 103     default_poll_event,           /* poll_event */
 104     file_flush,                   /* flush */
 105     file_get_fd_type,             /* get_fd_type */
 106     default_fd_ioctl,             /* ioctl */
 107     default_fd_queue_async,       /* queue_async */
 108     default_fd_reselect_async,    /* reselect_async */
 109     default_fd_cancel_async       /* cancel_async */
 110 };
 111
 112 static inline int is_overlapped( const struct file *file )
 113 {
 114     return !(get_fd_options( file->fd ) & (FILE_SYNCHRONOUS_IO_ALERT | FILE_SYNCHRONOUS_IO_NONALERT));
 115 }
 116
 117 /* create a file from a file descriptor */
 118 /* if the function fails the fd is closed */
 119 static struct file *create_file_for_fd( int fd, unsigned int access, unsigned int sharing )
 120 {
 121     struct file *file;
 122     struct stat st;
 123
 124     if (fstat( fd, &st ) == -1)
 125     {
 126         file_set_error();
 127         return NULL;
 128     }
 129
 130     if ((file = alloc_object( &file_ops )))
 131     {
 132         file->mode = st.st_mode;
 133         file->access = default_fd_map_access( &file->obj, access );
 134         if (!(file->fd = create_anonymous_fd( &file_fd_ops, fd, &file->obj,
 135                                               FILE_SYNCHRONOUS_IO_NONALERT )))
 136         {
 137             release_object( file );
 138             return NULL;
 139         }
 140     }
 141     return file;
 142 }
 143
 144 static struct object *create_file_obj( struct fd *fd, unsigned int access, mode_t mode )
 145 {
 146     struct file *file = alloc_object( &file_ops );
 147
 148     if (!file) return NULL;
 149     file->access  = access;
 150     file->mode    = mode;
 151     file->fd      = fd;
 152     grab_object( fd );
 153     set_fd_user( fd, &file_fd_ops, &file->obj );
 154     return &file->obj;
 155 }
 156
 157 static struct object *create_file( const char *nameptr, data_size_t len, unsigned int access,
 158                                    unsigned int sharing, int create, unsigned int options,
 159                                    unsigned int attrs, const struct security_descriptor *sd )
 160 {
 161     struct object *obj = NULL;
 162     struct fd *fd;
 163     int flags;
 164     char *name;
 165     mode_t mode;
 166
 167     if (!(name = mem_alloc( len + 1 ))) return NULL;
 168     memcpy( name, nameptr, len );
 169     name[len] = 0;
 170
 171     switch(create)
 172     {
 173     case FILE_CREATE:       flags = O_CREAT | O_EXCL; break;
 174     case FILE_OVERWRITE_IF: /* FIXME: the difference is whether we trash existing attr or not */
 175     case FILE_SUPERSEDE:    flags = O_CREAT | O_TRUNC; break;
 176     case FILE_OPEN:         flags = 0; break;
 177     case FILE_OPEN_IF:      flags = O_CREAT; break;
 178     case FILE_OVERWRITE:    flags = O_TRUNC; break;
 179     default:                set_error( STATUS_INVALID_PARAMETER ); goto done;
 180     }
 181
 182     if (sd)
 183     {
 184         const SID *owner = sd_get_owner( sd );
 185         if (!owner)
 186             owner = token_get_user( current->process->token );
 187         mode = sd_to_mode( sd, owner );
 188     }
 189     else
 190         mode = (attrs & FILE_ATTRIBUTE_READONLY) ? 0444 : 0666;
 191
 192     if (len >= 4 &&
 193         (!strcasecmp( name + len - 4, ".exe" ) || !strcasecmp( name + len - 4, ".com" )))
 194     {
 195         if (mode & S_IRUSR)
 196             mode |= S_IXUSR;
 197         if (mode & S_IRGRP)
 198             mode |= S_IXGRP;
 199         if (mode & S_IROTH)
 200             mode |= S_IXOTH;
 201     }
 202
 203     access = generic_file_map_access( access );
 204
 205     /* FIXME: should set error to STATUS_OBJECT_NAME_COLLISION if file existed before */
 206     fd = open_fd( name, flags | O_NONBLOCK | O_LARGEFILE, &mode, access, sharing, options );
 207     if (!fd) goto done;
 208
 209     if (S_ISDIR(mode))
 210         obj = create_dir_obj( fd );
 211     else if (S_ISCHR(mode) && is_serial_fd( fd ))
 212         obj = create_serial( fd );
 213     else
 214         obj = create_file_obj( fd, access, mode );
 215
 216     release_object( fd );
 217
 218 done:
 219     free( name );
 220     return obj;
 221 }
 222
 223 /* check if two file objects point to the same file */
 224 int is_same_file( struct file *file1, struct file *file2 )
 225 {
 226     return is_same_file_fd( file1->fd, file2->fd );
 227 }
 228
 229 /* create a temp file for anonymous mappings */
 230 struct file *create_temp_file( int access )
 231 {
 232     char tmpfn[16];
 233     int fd;
 234
 235     sprintf( tmpfn, "anonmap.XXXXXX" );  /* create it in the server directory */
 236     fd = mkstemps( tmpfn, 0 );
 237     if (fd == -1)
 238     {
 239         file_set_error();
 240         return NULL;
 241     }
 242     unlink( tmpfn );
 243     return create_file_for_fd( fd, access, 0 );
 244 }
 245
 246 static void file_dump( struct object *obj, int verbose )
 247 {
 248     struct file *file = (struct file *)obj;
 249     assert( obj->ops == &file_ops );
 250     fprintf( stderr, "File fd=%p\n", file->fd );
 251 }
 252
 253 static int file_get_poll_events( struct fd *fd )
 254 {
 255     struct file *file = get_fd_user( fd );
 256     int events = 0;
 257     assert( file->obj.ops == &file_ops );
 258     if (file->access & FILE_UNIX_READ_ACCESS) events |= POLLIN;
 259     if (file->access & FILE_UNIX_WRITE_ACCESS) events |= POLLOUT;
 260     return events;
 261 }
 262
 263 static void file_flush( struct fd *fd, struct event **event )
 264 {
 265     int unix_fd = get_unix_fd( fd );
 266     if (unix_fd != -1 && fsync( unix_fd ) == -1) file_set_error();
 267 }
 268
 269 static enum server_fd_type file_get_fd_type( struct fd *fd )
 270 {
 271     struct file *file = get_fd_user( fd );
 272
 273     if (S_ISREG(file->mode) || S_ISBLK(file->mode)) return FD_TYPE_FILE;
 274     if (S_ISDIR(file->mode)) return FD_TYPE_DIR;
 275     return FD_TYPE_CHAR;
 276 }
 277
 278 static struct fd *file_get_fd( struct object *obj )
 279 {
 280     struct file *file = (struct file *)obj;
 281     assert( obj->ops == &file_ops );
 282     return (struct fd *)grab_object( file->fd );
 283 }
 284
 285 static unsigned int generic_file_map_access( unsigned int access )
 286 {
 287     if (access & GENERIC_READ)    access |= FILE_GENERIC_READ;
 288     if (access & GENERIC_WRITE)   access |= FILE_GENERIC_WRITE;
 289     if (access & GENERIC_EXECUTE) access |= FILE_GENERIC_EXECUTE;
 290     if (access & GENERIC_ALL)     access |= FILE_ALL_ACCESS;
 291     return access & ~(GENERIC_READ | GENERIC_WRITE | GENERIC_EXECUTE | GENERIC_ALL);
 292 }
 293
 294 static struct security_descriptor *file_get_sd( struct object *obj )
 295 {
 296     struct file *file = (struct file *)obj;
 297     struct stat st;
 298     int unix_fd;
 299     struct security_descriptor *sd;
 300     const SID *user;
 301     const SID *group;
 302     size_t dacl_size;
 303     ACE_HEADER *current_ace;
 304     ACCESS_ALLOWED_ACE *aaa;
 305     ACL *dacl;
 306     SID *sid;
 307     char *ptr;
 308     const SID *world_sid = security_world_sid;
 309     const SID *local_system_sid = security_local_system_sid;
 310
 311     assert( obj->ops == &file_ops );
 312
 313     unix_fd = get_file_unix_fd( file );
 314
 315     if (unix_fd == -1) return obj->sd;
 316
 317     if (fstat( unix_fd, &st ) == -1)
 318         return obj->sd;
 319
 320     /* mode and uid the same? if so, no need to re-generate security descriptor */
 321     if (obj->sd && (st.st_mode & (S_IRWXU|S_IRWXO)) == (file->mode & (S_IRWXU|S_IRWXO)) &&
 322         (st.st_uid == file->uid))
 323         return obj->sd;
 324
 325     user = security_unix_uid_to_sid( st.st_uid );
 326     group = token_get_primary_group( current->process->token );
 327
 328     dacl_size = sizeof(ACL) + FIELD_OFFSET(ACCESS_ALLOWED_ACE, SidStart) +
 329         FIELD_OFFSET(SID, SubAuthority[local_system_sid->SubAuthorityCount]);
 330     if (st.st_mode & S_IRWXU)
 331         dacl_size += FIELD_OFFSET(ACCESS_ALLOWED_ACE, SidStart) +
 332             FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]);
 333     if ((!(st.st_mode & S_IRUSR) && (st.st_mode & (S_IRGRP|S_IROTH))) ||
 334         (!(st.st_mode & S_IWUSR) && (st.st_mode & (S_IWGRP|S_IWOTH))) ||
 335         (!(st.st_mode & S_IXUSR) && (st.st_mode & (S_IXGRP|S_IXOTH))))
 336         dacl_size += FIELD_OFFSET(ACCESS_DENIED_ACE, SidStart) +
 337             FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]);
 338     if (st.st_mode & S_IRWXO)
 339         dacl_size += FIELD_OFFSET(ACCESS_ALLOWED_ACE, SidStart) +
 340             FIELD_OFFSET(SID, SubAuthority[world_sid->SubAuthorityCount]);
 341
 342     sd = mem_alloc( sizeof(struct security_descriptor) +
 343                     FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]) +
 344                     FIELD_OFFSET(SID, SubAuthority[group->SubAuthorityCount]) +
 345                     dacl_size );
 346     if (!sd) return obj->sd;
 347
 348     sd->control = SE_DACL_PRESENT;
 349     sd->owner_len = FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]);
 350     sd->group_len = FIELD_OFFSET(SID, SubAuthority[group->SubAuthorityCount]);
 351     sd->sacl_len = 0;
 352     sd->dacl_len = dacl_size;
 353
 354     ptr = (char *)(sd + 1);
 355     memcpy( ptr, user, sd->owner_len );
 356     ptr += sd->owner_len;
 357     memcpy( ptr, group, sd->group_len );
 358     ptr += sd->group_len;
 359
 360     dacl = (ACL *)ptr;
 361     dacl->AclRevision = ACL_REVISION;
 362     dacl->Sbz1 = 0;
 363     dacl->AclSize = dacl_size;
 364     dacl->AceCount = 1 + (st.st_mode & S_IRWXU ? 1 : 0) + (st.st_mode & S_IRWXO ? 1 : 0);
 365     if ((!(st.st_mode & S_IRUSR) && (st.st_mode & (S_IRGRP|S_IROTH))) ||
 366         (!(st.st_mode & S_IWUSR) && (st.st_mode & (S_IWGRP|S_IWOTH))) ||
 367         (!(st.st_mode & S_IXUSR) && (st.st_mode & (S_IXGRP|S_IXOTH))))
 368         dacl->AceCount++;
 369     dacl->Sbz2 = 0;
 370
 371     /* always give FILE_ALL_ACCESS for Local System */
 372     aaa = (ACCESS_ALLOWED_ACE *)(dacl + 1);
 373     current_ace = &aaa->Header;
 374     aaa->Header.AceType = ACCESS_ALLOWED_ACE_TYPE;
 375     aaa->Header.AceFlags = 0;
 376     aaa->Header.AceSize = FIELD_OFFSET(ACCESS_ALLOWED_ACE, SidStart) +
 377         FIELD_OFFSET(SID, SubAuthority[local_system_sid->SubAuthorityCount]);
 378     aaa->Mask = FILE_ALL_ACCESS;
 379     sid = (SID *)&aaa->SidStart;
 380     memcpy( sid, local_system_sid, FIELD_OFFSET(SID, SubAuthority[local_system_sid->SubAuthorityCount]) );
 381
 382     if (st.st_mode & S_IRWXU)
 383     {
 384         /* appropriate access rights for the user */
 385         aaa = (ACCESS_ALLOWED_ACE *)ace_next( current_ace );
 386         current_ace = &aaa->Header;
 387         aaa->Header.AceType = ACCESS_ALLOWED_ACE_TYPE;
 388         aaa->Header.AceFlags = 0;
 389         aaa->Header.AceSize = FIELD_OFFSET(ACCESS_ALLOWED_ACE, SidStart) +
 390                               FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]);
 391         aaa->Mask = WRITE_DAC | WRITE_OWNER;
 392         if (st.st_mode & S_IRUSR)
 393             aaa->Mask |= FILE_GENERIC_READ;
 394         if (st.st_mode & S_IWUSR)
 395             aaa->Mask |= FILE_GENERIC_WRITE | DELETE;
 396         if (st.st_mode & S_IXUSR)
 397             aaa->Mask |= FILE_GENERIC_EXECUTE;
 398         sid = (SID *)&aaa->SidStart;
 399         memcpy( sid, user, FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]) );
 400     }
 401     if ((!(st.st_mode & S_IRUSR) && (st.st_mode & (S_IRGRP|S_IROTH))) ||
 402         (!(st.st_mode & S_IWUSR) && (st.st_mode & (S_IWGRP|S_IWOTH))) ||
 403         (!(st.st_mode & S_IXUSR) && (st.st_mode & (S_IXGRP|S_IXOTH))))
 404     {
 405         /* deny just in case the user is a member of the group */
 406         ACCESS_DENIED_ACE *ada = (ACCESS_DENIED_ACE *)ace_next( current_ace );
 407         current_ace = &ada->Header;
 408         ada->Header.AceType = ACCESS_DENIED_ACE_TYPE;
 409         ada->Header.AceFlags = 0;
 410         ada->Header.AceSize = FIELD_OFFSET(ACCESS_DENIED_ACE, SidStart) +
 411                               FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]);
 412         ada->Mask = 0;
 413         if (!(st.st_mode & S_IRUSR) && (st.st_mode & (S_IRGRP|S_IROTH)))
 414             ada->Mask |= FILE_GENERIC_READ;
 415         if (!(st.st_mode & S_IWUSR) && (st.st_mode & (S_IWGRP|S_IROTH)))
 416             ada->Mask |= FILE_GENERIC_WRITE | DELETE;
 417         if (!(st.st_mode & S_IXUSR) && (st.st_mode & (S_IXGRP|S_IXOTH)))
 418             ada->Mask |= FILE_GENERIC_EXECUTE;
 419         ada->Mask &= ~STANDARD_RIGHTS_ALL; /* never deny standard rights */
 420         sid = (SID *)&ada->SidStart;
 421         memcpy( sid, user, FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]) );
 422     }
 423     if (st.st_mode & S_IRWXO)
 424     {
 425         /* appropriate access rights for Everyone */
 426         aaa = (ACCESS_ALLOWED_ACE *)ace_next( current_ace );
 427         current_ace = &aaa->Header;
 428         aaa->Header.AceType = ACCESS_ALLOWED_ACE_TYPE;
 429         aaa->Header.AceFlags = 0;
 430         aaa->Header.AceSize = FIELD_OFFSET(ACCESS_ALLOWED_ACE, SidStart) +
 431                              FIELD_OFFSET(SID, SubAuthority[world_sid->SubAuthorityCount]);
 432         aaa->Mask = 0;
 433         if (st.st_mode & S_IROTH)
 434             aaa->Mask |= FILE_GENERIC_READ;
 435         if (st.st_mode & S_IWOTH)
 436             aaa->Mask |= FILE_GENERIC_WRITE | DELETE;
 437         if (st.st_mode & S_IXOTH)
 438             aaa->Mask |= FILE_GENERIC_EXECUTE;
 439         sid = (SID *)&aaa->SidStart;
 440         memcpy( sid, world_sid, FIELD_OFFSET(SID, SubAuthority[world_sid->SubAuthorityCount]) );
 441     }
 442
 443     file->mode = st.st_mode;
 444     file->uid = st.st_uid;
 445     free( obj->sd );
 446     obj->sd = sd;
 447     return sd;
 448 }
 449
 450 static mode_t sd_to_mode( const struct security_descriptor *sd, const SID *owner )
 451 {
 452     mode_t new_mode = 0;
 453     mode_t denied_mode = 0;
 454     int present;
 455     const ACL *dacl = sd_get_dacl( sd, &present );
 456     if (present && dacl)
 457     {
 458         const ACE_HEADER *ace = (const ACE_HEADER *)(dacl + 1);
 459         ULONG i;
 460         for (i = 0; i < dacl->AceCount; i++, ace = ace_next( ace ))
 461         {
 462             const ACCESS_ALLOWED_ACE *aa_ace;
 463             const ACCESS_DENIED_ACE *ad_ace;
 464             const SID *sid;
 465
 466             if (ace->AceFlags & INHERIT_ONLY_ACE) continue;
 467
 468             switch (ace->AceType)
 469             {
 470                 case ACCESS_DENIED_ACE_TYPE:
 471                     ad_ace = (const ACCESS_DENIED_ACE *)ace;
 472                     sid = (const SID *)&ad_ace->SidStart;
 473                     if (security_equal_sid( sid, security_world_sid ))
 474                     {
 475                         unsigned int access = generic_file_map_access( ad_ace->Mask );
 476                         if (access & FILE_READ_DATA)
 477                             denied_mode |= S_IRUSR|S_IRGRP|S_IROTH;
 478                         if (access & FILE_WRITE_DATA)
 479                             denied_mode |= S_IWUSR|S_IWGRP|S_IWOTH;
 480                         if (access & FILE_EXECUTE)
 481                             denied_mode |= S_IXUSR|S_IXGRP|S_IXOTH;
 482                     }
 483                     else if (security_equal_sid( sid, owner ))
 484                     {
 485                         unsigned int access = generic_file_map_access( ad_ace->Mask );
 486                         if (access & FILE_READ_DATA)
 487                             denied_mode |= S_IRUSR;
 488                         if (access & FILE_WRITE_DATA)
 489                             denied_mode |= S_IWUSR;
 490                         if (access & FILE_EXECUTE)
 491                             denied_mode |= S_IXUSR;
 492                     }
 493                     break;
 494                 case ACCESS_ALLOWED_ACE_TYPE:
 495                     aa_ace = (const ACCESS_ALLOWED_ACE *)ace;
 496                     sid = (const SID *)&aa_ace->SidStart;
 497                     if (security_equal_sid( sid, security_world_sid ))
 498                     {
 499                         unsigned int access = generic_file_map_access( aa_ace->Mask );
 500                         if (access & FILE_READ_DATA)
 501                             new_mode |= S_IRUSR|S_IRGRP|S_IROTH;
 502                         if (access & FILE_WRITE_DATA)
 503                             new_mode |= S_IWUSR|S_IWGRP|S_IWOTH;
 504                         if (access & FILE_EXECUTE)
 505                             new_mode |= S_IXUSR|S_IXGRP|S_IXOTH;
 506                     }
 507                     else if (security_equal_sid( sid, owner ))
 508                     {
 509                         unsigned int access = generic_file_map_access( aa_ace->Mask );
 510                         if (access & FILE_READ_DATA)
 511                             new_mode |= S_IRUSR;
 512                         if (access & FILE_WRITE_DATA)
 513                             new_mode |= S_IWUSR;
 514                         if (access & FILE_EXECUTE)
 515                             new_mode |= S_IXUSR;
 516                     }
 517                     break;
 518             }
 519         }
 520     }
 521     else
 522         /* no ACL means full access rights to anyone */
 523         new_mode = S_IRWXU | S_IRWXO;
 524
 525     return new_mode & ~denied_mode;
 526 }
 527
 528 static int file_set_sd( struct object *obj, const struct security_descriptor *sd,
 529                         unsigned int set_info )
 530 {
 531     struct file *file = (struct file *)obj;
 532     const SID *owner;
 533     mode_t mode;
 534     int unix_fd;
 535
 536     assert( obj->ops == &file_ops );
 537
 538     unix_fd = get_file_unix_fd( file );
 539
 540     if (unix_fd == -1) return 1;
 541
 542     if (set_info & OWNER_SECURITY_INFORMATION)
 543     {
 544         owner = sd_get_owner( sd );
 545         if (!owner)
 546         {
 547             set_error( STATUS_INVALID_SECURITY_DESCR );
 548             return 0;
 549         }
 550         if (!obj->sd || !security_equal_sid( owner, sd_get_owner( obj->sd ) ))
 551         {
 552             /* FIXME: get Unix uid and call fchown */
 553         }
 554     }
 555     else if (obj->sd)
 556         owner = sd_get_owner( obj->sd );
 557     else
 558         owner = token_get_user( current->process->token );
 559
 560     /* group and sacl not supported */
 561
 562     if (set_info & DACL_SECURITY_INFORMATION)
 563     {
 564         /* keep the bits that we don't map to access rights in the ACL */
 565         mode = file->mode & (S_ISUID|S_ISGID|S_ISVTX|S_IRWXG);
 566         mode |= sd_to_mode( sd, owner );
 567
 568         if (file->mode != mode)
 569         {
 570             if (fchmod( unix_fd, mode ) == -1)
 571             {
 572                 file_set_error();
 573                 return 0;
 574             }
 575
 576             file->mode = mode;
 577         }
 578     }
 579     return 1;
 580 }
 581
 582 static void file_destroy( struct object *obj )
 583 {
 584     struct file *file = (struct file *)obj;
 585     assert( obj->ops == &file_ops );
 586
 587     if (file->fd) release_object( file->fd );
 588 }
 589
 590 /* set the last error depending on errno */
 591 void file_set_error(void)
 592 {
 593     switch (errno)
 594     {
 595     case ETXTBSY:
 596     case EAGAIN:    set_error( STATUS_SHARING_VIOLATION ); break;
 597     case EBADF:     set_error( STATUS_INVALID_HANDLE ); break;
 598     case ENOSPC:    set_error( STATUS_DISK_FULL ); break;
 599     case EACCES:
 600     case ESRCH:
 601     case EPERM:     set_error( STATUS_ACCESS_DENIED ); break;
 602     case EROFS:     set_error( STATUS_MEDIA_WRITE_PROTECTED ); break;
 603     case EBUSY:     set_error( STATUS_FILE_LOCK_CONFLICT ); break;
 604     case ENOENT:    set_error( STATUS_NO_SUCH_FILE ); break;
 605     case EISDIR:    set_error( STATUS_FILE_IS_A_DIRECTORY ); break;
 606     case ENFILE:
 607     case EMFILE:    set_error( STATUS_TOO_MANY_OPENED_FILES ); break;
 608     case EEXIST:    set_error( STATUS_OBJECT_NAME_COLLISION ); break;
 609     case EINVAL:    set_error( STATUS_INVALID_PARAMETER ); break;
 610     case ESPIPE:    set_error( STATUS_ILLEGAL_FUNCTION ); break;
 611     case ENOTEMPTY: set_error( STATUS_DIRECTORY_NOT_EMPTY ); break;
 612     case EIO:       set_error( STATUS_ACCESS_VIOLATION ); break;
 613     case ENOTDIR:   set_error( STATUS_NOT_A_DIRECTORY ); break;
 614     case EFBIG:     set_error( STATUS_SECTION_TOO_BIG ); break;
 615     case ENODEV:    set_error( STATUS_NO_SUCH_DEVICE ); break;
 616     case ENXIO:     set_error( STATUS_NO_SUCH_DEVICE ); break;
 617 #ifdef EOVERFLOW
 618     case EOVERFLOW: set_error( STATUS_INVALID_PARAMETER ); break;
 619 #endif
 620     default:
 621         perror("wineserver: file_set_error() can't map error");
 622         set_error( STATUS_UNSUCCESSFUL );
 623         break;
 624     }
 625 }
 626
 627 struct file *get_file_obj( struct process *process, obj_handle_t handle, unsigned int access )
 628 {
 629     return (struct file *)get_handle_obj( process, handle, access, &file_ops );
 630 }
 631
 632 int get_file_unix_fd( struct file *file )
 633 {
 634     return get_unix_fd( file->fd );
 635 }
 636
 637 struct file *grab_file_unless_removable( struct file *file )
 638 {
 639     if (is_fd_removable( file->fd )) return NULL;
 640     return (struct file *)grab_object( file );
 641 }
 642
 643 /* extend a file beyond the current end of file */
 644 static int extend_file( struct file *file, file_pos_t new_size )
 645 {
 646     static const char zero;
 647     int unix_fd = get_file_unix_fd( file );
 648     off_t size = new_size;
 649
 650     if (unix_fd == -1) return 0;
 651
 652     if (sizeof(new_size) > sizeof(size) && size != new_size)
 653     {
 654         set_error( STATUS_INVALID_PARAMETER );
 655         return 0;
 656     }
 657     /* extend the file one byte beyond the requested size and then truncate it */
 658     /* this should work around ftruncate implementations that can't extend files */
 659     if (pwrite( unix_fd, &zero, 1, size ) != -1)
 660     {
 661         ftruncate( unix_fd, size );
 662         return 1;
 663     }
 664     file_set_error();
 665     return 0;
 666 }
 667
 668 /* try to grow the file to the specified size */
 669 int grow_file( struct file *file, file_pos_t size )
 670 {
 671     struct stat st;
 672     int unix_fd = get_file_unix_fd( file );
 673
 674     if (unix_fd == -1) return 0;
 675
 676     if (fstat( unix_fd, &st ) == -1)
 677     {
 678         file_set_error();
 679         return 0;
 680     }
 681     if (st.st_size >= size) return 1;  /* already large enough */
 682     return extend_file( file, size );
 683 }
 684
 685 /* create a file */
 686 DECL_HANDLER(create_file)
 687 {
 688     struct object *file;
 689     const struct object_attributes *objattr = get_req_data();
 690     const struct security_descriptor *sd;
 691     const char *name;
 692     data_size_t name_len;
 693
 694     reply->handle = 0;
 695
 696     if (!objattr_is_valid( objattr, get_req_data_size() ))
 697         return;
 698     /* name is transferred in the unix codepage outside of the objattr structure */
 699     if (objattr->name_len)
 700     {
 701         set_error( STATUS_INVALID_PARAMETER );
 702         return;
 703     }
 704
 705     sd = objattr->sd_len ? (const struct security_descriptor *)(objattr + 1) : NULL;
 706
 707     name = (const char *)get_req_data() + sizeof(*objattr) + objattr->sd_len;
 708     name_len = get_req_data_size() - sizeof(*objattr) - objattr->sd_len;
 709
 710     reply->handle = 0;
 711     if ((file = create_file( name, name_len, req->access,
 712                              req->sharing, req->create, req->options,
 713                              req->attrs, sd )))
 714     {
 715         reply->handle = alloc_handle( current->process, file, req->access, req->attributes );
 716         release_object( file );
 717     }
 718 }
 719
 720 /* allocate a file handle for a Unix fd */
 721 DECL_HANDLER(alloc_file_handle)
 722 {
 723     struct file *file;
 724     int fd;
 725
 726     reply->handle = 0;
 727     if ((fd = thread_get_inflight_fd( current, req->fd )) == -1)
 728     {
 729         set_error( STATUS_INVALID_HANDLE );
 730         return;
 731     }
 732     if ((file = create_file_for_fd( fd, req->access, FILE_SHARE_READ | FILE_SHARE_WRITE )))
 733     {
 734         reply->handle = alloc_handle( current->process, file, req->access, req->attributes );
 735         release_object( file );
 736     }
 737 }
 738
 739 /* lock a region of a file */
 740 DECL_HANDLER(lock_file)
 741 {
 742     struct file *file;
 743
 744     if ((file = get_file_obj( current->process, req->handle, 0 )))
 745     {
 746         reply->handle = lock_fd( file->fd, req->offset, req->count, req->shared, req->wait );
 747         reply->overlapped = is_overlapped( file );
 748         release_object( file );
 749     }
 750 }
 751
 752 /* unlock a region of a file */
 753 DECL_HANDLER(unlock_file)
 754 {
 755     struct file *file;
 756
 757     if ((file = get_file_obj( current->process, req->handle, 0 )))
 758     {
 759         unlock_fd( file->fd, req->offset, req->count );
 760         release_object( file );
 761     }
 762 }