server/mapping.c

   1 /*
   2  * Server-side file mapping management
   3  *
   4  * Copyright (C) 1999 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 <stdarg.h>
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <sys/stat.h>
  29 #include <unistd.h>
  30
  31 #include "ntstatus.h"
  32 #define WIN32_NO_STATUS
  33 #include "windef.h"
  34 #include "winternl.h"
  35
  36 #include "file.h"
  37 #include "handle.h"
  38 #include "thread.h"
  39 #include "request.h"
  40 #include "security.h"
  41
  42 struct mapping
  43 {
  44     struct object   obj;             /* object header */
  45     file_pos_t      size;            /* mapping size */
  46     int             protect;         /* protection flags */
  47     struct file    *file;            /* file mapped */
  48     int             header_size;     /* size of headers (for PE image mapping) */
  49     void           *base;            /* default base addr (for PE image mapping) */
  50     struct file    *shared_file;     /* temp file for shared PE mapping */
  51     struct list     shared_entry;    /* entry in global shared PE mappings list */
  52 };
  53
  54 static void mapping_dump( struct object *obj, int verbose );
  55 static struct object_type *mapping_get_type( struct object *obj );
  56 static struct fd *mapping_get_fd( struct object *obj );
  57 static unsigned int mapping_map_access( struct object *obj, unsigned int access );
  58 static void mapping_destroy( struct object *obj );
  59
  60 static const struct object_ops mapping_ops =
  61 {
  62     sizeof(struct mapping),      /* size */
  63     mapping_dump,                /* dump */
  64     mapping_get_type,            /* get_type */
  65     no_add_queue,                /* add_queue */
  66     NULL,                        /* remove_queue */
  67     NULL,                        /* signaled */
  68     NULL,                        /* satisfied */
  69     no_signal,                   /* signal */
  70     mapping_get_fd,              /* get_fd */
  71     mapping_map_access,          /* map_access */
  72     default_get_sd,              /* get_sd */
  73     default_set_sd,              /* set_sd */
  74     no_lookup_name,              /* lookup_name */
  75     no_open_file,                /* open_file */
  76     fd_close_handle,             /* close_handle */
  77     mapping_destroy              /* destroy */
  78 };
  79
  80 static struct list shared_list = LIST_INIT(shared_list);
  81
  82 #ifdef __i386__
  83
  84 /* These are always the same on an i386, and it will be faster this way */
  85 # define page_mask  0xfff
  86 # define page_shift 12
  87 # define init_page_size() do { /* nothing */ } while(0)
  88
  89 #else  /* __i386__ */
  90
  91 static int page_shift, page_mask;
  92
  93 static void init_page_size(void)
  94 {
  95     int page_size;
  96 # ifdef HAVE_GETPAGESIZE
  97     page_size = getpagesize();
  98 # else
  99 #  ifdef __svr4__
 100     page_size = sysconf(_SC_PAGESIZE);
 101 #  else
 102 #   error Cannot get the page size on this platform
 103 #  endif
 104 # endif
 105     page_mask = page_size - 1;
 106     /* Make sure we have a power of 2 */
 107     assert( !(page_size & page_mask) );
 108     page_shift = 0;
 109     while ((1 << page_shift) != page_size) page_shift++;
 110 }
 111 #endif  /* __i386__ */
 112
 113 #define ROUND_SIZE(size)  (((size) + page_mask) & ~page_mask)
 114
 115
 116 /* find the shared PE mapping for a given mapping */
 117 static struct file *get_shared_file( struct mapping *mapping )
 118 {
 119     struct mapping *ptr;
 120
 121     LIST_FOR_EACH_ENTRY( ptr, &shared_list, struct mapping, shared_entry )
 122         if (is_same_file( ptr->file, mapping->file ))
 123             return (struct file *)grab_object( ptr->shared_file );
 124     return NULL;
 125 }
 126
 127 /* return the size of the memory mapping and file range of a given section */
 128 static inline void get_section_sizes( const IMAGE_SECTION_HEADER *sec, size_t *map_size,
 129                                       off_t *file_start, size_t *file_size )
 130 {
 131     static const unsigned int sector_align = 0x1ff;
 132
 133     if (!sec->Misc.VirtualSize) *map_size = ROUND_SIZE( sec->SizeOfRawData );
 134     else *map_size = ROUND_SIZE( sec->Misc.VirtualSize );
 135
 136     *file_start = sec->PointerToRawData & ~sector_align;
 137     *file_size = (sec->SizeOfRawData + (sec->PointerToRawData & sector_align) + sector_align) & ~sector_align;
 138     if (*file_size > *map_size) *file_size = *map_size;
 139 }
 140
 141 /* allocate and fill the temp file for a shared PE image mapping */
 142 static int build_shared_mapping( struct mapping *mapping, int fd,
 143                                  IMAGE_SECTION_HEADER *sec, unsigned int nb_sec )
 144 {
 145     unsigned int i;
 146     file_pos_t total_size;
 147     size_t file_size, map_size, max_size;
 148     off_t shared_pos, read_pos, write_pos;
 149     char *buffer = NULL;
 150     int shared_fd;
 151     long toread;
 152
 153     /* compute the total size of the shared mapping */
 154
 155     total_size = max_size = 0;
 156     for (i = 0; i < nb_sec; i++)
 157     {
 158         if ((sec[i].Characteristics & IMAGE_SCN_MEM_SHARED) &&
 159             (sec[i].Characteristics & IMAGE_SCN_MEM_WRITE))
 160         {
 161             get_section_sizes( &sec[i], &map_size, &read_pos, &file_size );
 162             if (file_size > max_size) max_size = file_size;
 163             total_size += map_size;
 164         }
 165     }
 166     if (!total_size) return 1;  /* nothing to do */
 167
 168     if ((mapping->shared_file = get_shared_file( mapping ))) return 1;
 169
 170     /* create a temp file for the mapping */
 171
 172     if (!(mapping->shared_file = create_temp_file( FILE_GENERIC_READ|FILE_GENERIC_WRITE ))) return 0;
 173     if (!grow_file( mapping->shared_file, total_size )) goto error;
 174     if ((shared_fd = get_file_unix_fd( mapping->shared_file )) == -1) goto error;
 175
 176     if (!(buffer = malloc( max_size ))) goto error;
 177
 178     /* copy the shared sections data into the temp file */
 179
 180     shared_pos = 0;
 181     for (i = 0; i < nb_sec; i++)
 182     {
 183         if (!(sec[i].Characteristics & IMAGE_SCN_MEM_SHARED)) continue;
 184         if (!(sec[i].Characteristics & IMAGE_SCN_MEM_WRITE)) continue;
 185         get_section_sizes( &sec[i], &map_size, &read_pos, &file_size );
 186         write_pos = shared_pos;
 187         shared_pos += map_size;
 188         if (!sec[i].PointerToRawData || !file_size) continue;
 189         toread = file_size;
 190         while (toread)
 191         {
 192             long res = pread( fd, buffer + file_size - toread, toread, read_pos );
 193             if (!res && toread < 0x200)  /* partial sector at EOF is not an error */
 194             {
 195                 file_size -= toread;
 196                 break;
 197             }
 198             if (res <= 0) goto error;
 199             toread -= res;
 200             read_pos += res;
 201         }
 202         if (pwrite( shared_fd, buffer, file_size, write_pos ) != file_size) goto error;
 203     }
 204     free( buffer );
 205     return 1;
 206
 207  error:
 208     release_object( mapping->shared_file );
 209     mapping->shared_file = NULL;
 210     free( buffer );
 211     return 0;
 212 }
 213
 214 /* retrieve the mapping parameters for an executable (PE) image */
 215 static int get_image_params( struct mapping *mapping )
 216 {
 217     IMAGE_DOS_HEADER dos;
 218     IMAGE_NT_HEADERS nt;
 219     IMAGE_SECTION_HEADER *sec = NULL;
 220     struct fd *fd;
 221     off_t pos;
 222     int unix_fd, size, toread;
 223
 224     /* load the headers */
 225
 226     if (!(fd = mapping_get_fd( &mapping->obj ))) return 0;
 227     if ((unix_fd = get_unix_fd( fd )) == -1) goto error;
 228     if (pread( unix_fd, &dos, sizeof(dos), 0 ) != sizeof(dos)) goto error;
 229     if (dos.e_magic != IMAGE_DOS_SIGNATURE) goto error;
 230     pos = dos.e_lfanew;
 231
 232     if (pread( unix_fd, &nt.Signature, sizeof(nt.Signature), pos ) != sizeof(nt.Signature))
 233         goto error;
 234     pos += sizeof(nt.Signature);
 235     if (nt.Signature != IMAGE_NT_SIGNATURE) goto error;
 236     if (pread( unix_fd, &nt.FileHeader, sizeof(nt.FileHeader), pos ) != sizeof(nt.FileHeader))
 237         goto error;
 238     pos += sizeof(nt.FileHeader);
 239     /* zero out Optional header in the case it's not present or partial */
 240     memset(&nt.OptionalHeader, 0, sizeof(nt.OptionalHeader));
 241     toread = min( sizeof(nt.OptionalHeader), nt.FileHeader.SizeOfOptionalHeader );
 242     if (pread( unix_fd, &nt.OptionalHeader, toread, pos ) != toread) goto error;
 243     pos += nt.FileHeader.SizeOfOptionalHeader;
 244
 245     /* load the section headers */
 246
 247     size = sizeof(*sec) * nt.FileHeader.NumberOfSections;
 248     if (!(sec = malloc( size ))) goto error;
 249     if (pread( unix_fd, sec, size, pos ) != size) goto error;
 250
 251     if (!build_shared_mapping( mapping, unix_fd, sec, nt.FileHeader.NumberOfSections )) goto error;
 252
 253     if (mapping->shared_file) list_add_head( &shared_list, &mapping->shared_entry );
 254
 255     mapping->size        = ROUND_SIZE( nt.OptionalHeader.SizeOfImage );
 256     mapping->base        = (void *)nt.OptionalHeader.ImageBase;
 257     mapping->header_size = max( pos + size, nt.OptionalHeader.SizeOfHeaders );
 258     mapping->protect     = VPROT_IMAGE;
 259
 260     /* sanity check */
 261     if (pos + size > mapping->size) goto error;
 262
 263     free( sec );
 264     release_object( fd );
 265     return 1;
 266
 267  error:
 268     free( sec );
 269     release_object( fd );
 270     set_error( STATUS_INVALID_FILE_FOR_SECTION );
 271     return 0;
 272 }
 273
 274 /* get the size of the unix file associated with the mapping */
 275 static inline int get_file_size( struct file *file, file_pos_t *size )
 276 {
 277     struct stat st;
 278     int unix_fd = get_file_unix_fd( file );
 279
 280     if (unix_fd == -1 || fstat( unix_fd, &st ) == -1) return 0;
 281     *size = st.st_size;
 282     return 1;
 283 }
 284
 285 static struct object *create_mapping( struct directory *root, const struct unicode_str *name,
 286                                       unsigned int attr, file_pos_t size, int protect,
 287                                       obj_handle_t handle, const struct security_descriptor *sd )
 288 {
 289     struct mapping *mapping;
 290     int access = 0;
 291
 292     if (!page_mask) init_page_size();
 293
 294     if (!(mapping = create_named_object_dir( root, name, attr, &mapping_ops )))
 295         return NULL;
 296     if (get_error() == STATUS_OBJECT_NAME_EXISTS)
 297         return &mapping->obj;  /* Nothing else to do */
 298
 299     if (sd) default_set_sd( &mapping->obj, sd, OWNER_SECURITY_INFORMATION|
 300                                                GROUP_SECURITY_INFORMATION|
 301                                                DACL_SECURITY_INFORMATION|
 302                                                SACL_SECURITY_INFORMATION );
 303     mapping->header_size = 0;
 304     mapping->base        = NULL;
 305     mapping->shared_file = NULL;
 306
 307     if (protect & VPROT_READ) access |= FILE_READ_DATA;
 308     if (protect & VPROT_WRITE) access |= FILE_WRITE_DATA;
 309
 310     if (handle)
 311     {
 312         if (!(mapping->file = get_file_obj( current->process, handle, access ))) goto error;
 313         if (protect & VPROT_IMAGE)
 314         {
 315             if (!get_image_params( mapping )) goto error;
 316             return &mapping->obj;
 317         }
 318         if (!size)
 319         {
 320             if (!get_file_size( mapping->file, &size )) goto error;
 321             if (!size)
 322             {
 323                 set_error( STATUS_MAPPED_FILE_SIZE_ZERO );
 324                 goto error;
 325             }
 326         }
 327         else
 328         {
 329             if (!grow_file( mapping->file, size )) goto error;
 330         }
 331     }
 332     else  /* Anonymous mapping (no associated file) */
 333     {
 334         if (!size || (protect & VPROT_IMAGE))
 335         {
 336             set_error( STATUS_INVALID_PARAMETER );
 337             mapping->file = NULL;
 338             goto error;
 339         }
 340         if (!(mapping->file = create_temp_file( access ))) goto error;
 341         if (!grow_file( mapping->file, size )) goto error;
 342     }
 343     mapping->size    = (size + page_mask) & ~((file_pos_t)page_mask);
 344     mapping->protect = protect;
 345     return &mapping->obj;
 346
 347  error:
 348     release_object( mapping );
 349     return NULL;
 350 }
 351
 352 static void mapping_dump( struct object *obj, int verbose )
 353 {
 354     struct mapping *mapping = (struct mapping *)obj;
 355     assert( obj->ops == &mapping_ops );
 356     fprintf( stderr, "Mapping size=%08x%08x prot=%08x file=%p header_size=%08x base=%p "
 357              "shared_file=%p ",
 358              (unsigned int)(mapping->size >> 32), (unsigned int)mapping->size,
 359              mapping->protect, mapping->file, mapping->header_size,
 360              mapping->base, mapping->shared_file );
 361     dump_object_name( &mapping->obj );
 362     fputc( '\n', stderr );
 363 }
 364
 365 static struct object_type *mapping_get_type( struct object *obj )
 366 {
 367     static const WCHAR name[] = {'S','e','c','t','i','o','n'};
 368     static const struct unicode_str str = { name, sizeof(name) };
 369     return get_object_type( &str );
 370 }
 371
 372 static struct fd *mapping_get_fd( struct object *obj )
 373 {
 374     struct mapping *mapping = (struct mapping *)obj;
 375     return get_obj_fd( (struct object *)mapping->file );
 376 }
 377
 378 static unsigned int mapping_map_access( struct object *obj, unsigned int access )
 379 {
 380     if (access & GENERIC_READ)    access |= STANDARD_RIGHTS_READ | SECTION_QUERY | SECTION_MAP_READ;
 381     if (access & GENERIC_WRITE)   access |= STANDARD_RIGHTS_WRITE | SECTION_MAP_WRITE;
 382     if (access & GENERIC_EXECUTE) access |= STANDARD_RIGHTS_EXECUTE | SECTION_MAP_EXECUTE;
 383     if (access & GENERIC_ALL)     access |= SECTION_ALL_ACCESS;
 384     return access & ~(GENERIC_READ | GENERIC_WRITE | GENERIC_EXECUTE | GENERIC_ALL);
 385 }
 386
 387 static void mapping_destroy( struct object *obj )
 388 {
 389     struct mapping *mapping = (struct mapping *)obj;
 390     assert( obj->ops == &mapping_ops );
 391     if (mapping->file) release_object( mapping->file );
 392     if (mapping->shared_file)
 393     {
 394         release_object( mapping->shared_file );
 395         list_remove( &mapping->shared_entry );
 396     }
 397 }
 398
 399 int get_page_size(void)
 400 {
 401     if (!page_mask) init_page_size();
 402     return page_mask + 1;
 403 }
 404
 405 /* create a file mapping */
 406 DECL_HANDLER(create_mapping)
 407 {
 408     struct object *obj;
 409     struct unicode_str name;
 410     struct directory *root = NULL;
 411     const struct object_attributes *objattr = get_req_data();
 412     const struct security_descriptor *sd;
 413
 414     reply->handle = 0;
 415
 416     if (!objattr_is_valid( objattr, get_req_data_size() ))
 417         return;
 418
 419     sd = objattr->sd_len ? (const struct security_descriptor *)(objattr + 1) : NULL;
 420     objattr_get_name( objattr, &name );
 421
 422     if (objattr->rootdir && !(root = get_directory_obj( current->process, objattr->rootdir, 0 )))
 423         return;
 424
 425     if ((obj = create_mapping( root, &name, req->attributes, req->size, req->protect, req->file_handle, sd )))
 426     {
 427         if (get_error() == STATUS_OBJECT_NAME_EXISTS)
 428             reply->handle = alloc_handle( current->process, obj, req->access, req->attributes );
 429         else
 430             reply->handle = alloc_handle_no_access_check( current->process, obj, req->access, req->attributes );
 431         release_object( obj );
 432     }
 433
 434     if (root) release_object( root );
 435 }
 436
 437 /* open a handle to a mapping */
 438 DECL_HANDLER(open_mapping)
 439 {
 440     struct unicode_str name;
 441     struct directory *root = NULL;
 442     struct mapping *mapping;
 443
 444     get_req_unicode_str( &name );
 445     if (req->rootdir && !(root = get_directory_obj( current->process, req->rootdir, 0 )))
 446         return;
 447
 448     if ((mapping = open_object_dir( root, &name, req->attributes, &mapping_ops )))
 449     {
 450         reply->handle = alloc_handle( current->process, &mapping->obj, req->access, req->attributes );
 451         release_object( mapping );
 452     }
 453
 454     if (root) release_object( root );
 455 }
 456
 457 /* get a mapping information */
 458 DECL_HANDLER(get_mapping_info)
 459 {
 460     struct mapping *mapping;
 461     struct fd *fd;
 462
 463     if ((mapping = (struct mapping *)get_handle_obj( current->process, req->handle,
 464                                                      0, &mapping_ops )))
 465     {
 466         reply->size        = mapping->size;
 467         reply->protect     = mapping->protect;
 468         reply->header_size = mapping->header_size;
 469         reply->base        = mapping->base;
 470         reply->shared_file = 0;
 471         if ((fd = get_obj_fd( &mapping->obj )))
 472         {
 473             if (!is_fd_removable(fd))
 474                 reply->mapping = alloc_handle( current->process, mapping, 0, 0 );
 475             release_object( fd );
 476         }
 477         if (mapping->shared_file)
 478         {
 479             if (!(reply->shared_file = alloc_handle( current->process, mapping->shared_file,
 480                                                      GENERIC_READ|GENERIC_WRITE, 0 )))
 481             {
 482                 if (reply->mapping) close_handle( current->process, reply->mapping );
 483             }
 484         }
 485         release_object( mapping );
 486     }
 487 }