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