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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include "config.h"
  22
  23 #include <assert.h>
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <unistd.h>
  27
  28 #include "winnt.h"
  29 #include "winbase.h"
  30
  31 #include "handle.h"
  32 #include "thread.h"
  33 #include "request.h"
  34
  35 struct mapping
  36 {
  37     struct object   obj;             /* object header */
  38     int             size_high;       /* mapping size */
  39     int             size_low;        /* mapping size */
  40     int             protect;         /* protection flags */
  41     struct file    *file;            /* file mapped */
  42     int             header_size;     /* size of headers (for PE image mapping) */
  43     void           *base;            /* default base addr (for PE image mapping) */
  44     struct file    *shared_file;     /* temp file for shared PE mapping */
  45     int             shared_size;     /* shared mapping total size */
  46     struct mapping *shared_next;     /* next in shared PE mapping list */
  47     struct mapping *shared_prev;     /* prev in shared PE mapping list */
  48 };
  49
  50 static int mapping_get_fd( struct object *obj );
  51 static int mapping_get_info( struct object *obj, struct get_file_info_reply *reply, int *flags );
  52 static void mapping_dump( struct object *obj, int verbose );
  53 static void mapping_destroy( struct object *obj );
  54
  55 static const struct object_ops mapping_ops =
  56 {
  57     sizeof(struct mapping),      /* size */
  58     mapping_dump,                /* dump */
  59     no_add_queue,                /* add_queue */
  60     NULL,                        /* remove_queue */
  61     NULL,                        /* signaled */
  62     NULL,                        /* satisfied */
  63     NULL,                        /* get_poll_events */
  64     NULL,                        /* poll_event */
  65     mapping_get_fd,              /* get_fd */
  66     no_flush,                    /* flush */
  67     mapping_get_info,            /* get_file_info */
  68     NULL,                        /* queue_async */
  69     mapping_destroy              /* destroy */
  70 };
  71
  72 static struct mapping *shared_first;
  73
  74 #ifdef __i386__
  75
  76 /* These are always the same on an i386, and it will be faster this way */
  77 # define page_mask  0xfff
  78 # define page_shift 12
  79 # define init_page_size() do { /* nothing */ } while(0)
  80
  81 #else  /* __i386__ */
  82
  83 static int page_shift, page_mask;
  84
  85 static void init_page_size(void)
  86 {
  87     int page_size;
  88 # ifdef HAVE_GETPAGESIZE
  89     page_size = getpagesize();
  90 # else
  91 #  ifdef __svr4__
  92     page_size = sysconf(_SC_PAGESIZE);
  93 #  else
  94 #   error Cannot get the page size on this platform
  95 #  endif
  96 # endif
  97     page_mask = page_size - 1;
  98     /* Make sure we have a power of 2 */
  99     assert( !(page_size & page_mask) );
 100     page_shift = 0;
 101     while ((1 << page_shift) != page_size) page_shift++;
 102 }
 103 #endif  /* __i386__ */
 104
 105 #define ROUND_ADDR(addr) \
 106    ((int)(addr) & ~page_mask)
 107
 108 #define ROUND_SIZE(addr,size) \
 109    (((int)(size) + ((int)(addr) & page_mask) + page_mask) & ~page_mask)
 110
 111 /* get the fd to use for mmaping a file */
 112 inline static int get_mmap_fd( struct file *file )
 113 {
 114     struct object *obj;
 115     if (!(obj = (struct object *)file))
 116     {
 117         set_error( STATUS_INVALID_HANDLE );
 118         return -1;
 119     }
 120     return obj->ops->get_fd( obj );
 121 }
 122
 123 /* find the shared PE mapping for a given mapping */
 124 static struct file *get_shared_file( struct mapping *mapping )
 125 {
 126     struct mapping *ptr;
 127
 128     for (ptr = shared_first; ptr; ptr = ptr->shared_next)
 129         if (is_same_file( ptr->file, mapping->file ))
 130             return (struct file *)grab_object( ptr->shared_file );
 131     return NULL;
 132 }
 133
 134 /* allocate and fill the temp file for a shared PE image mapping */
 135 static int build_shared_mapping( struct mapping *mapping, int fd,
 136                                  IMAGE_SECTION_HEADER *sec, int nb_sec )
 137 {
 138     int i, max_size, total_size, pos;
 139     char *buffer = NULL;
 140     int shared_fd;
 141     long toread;
 142
 143     /* compute the total size of the shared mapping */
 144
 145     total_size = max_size = 0;
 146     for (i = 0; i < nb_sec; i++)
 147     {
 148         if ((sec[i].Characteristics & IMAGE_SCN_MEM_SHARED) &&
 149             (sec[i].Characteristics & IMAGE_SCN_MEM_WRITE))
 150         {
 151             int size = ROUND_SIZE( 0, sec[i].Misc.VirtualSize );
 152             if (size > max_size) max_size = size;
 153             total_size += size;
 154         }
 155     }
 156     if (!(mapping->shared_size = total_size)) return 1;  /* nothing to do */
 157
 158     if ((mapping->shared_file = get_shared_file( mapping ))) return 1;
 159
 160     /* create a temp file for the mapping */
 161
 162     if (!(mapping->shared_file = create_temp_file( GENERIC_READ|GENERIC_WRITE ))) goto error;
 163     if (!grow_file( mapping->shared_file, 0, total_size )) goto error;
 164     if ((shared_fd = get_mmap_fd( mapping->shared_file )) == -1) goto error;
 165
 166     if (!(buffer = malloc( max_size ))) goto error;
 167
 168     /* copy the shared sections data into the temp file */
 169
 170     for (i = pos = 0; i < nb_sec; i++)
 171     {
 172         if (!(sec[i].Characteristics & IMAGE_SCN_MEM_SHARED)) continue;
 173         if (!(sec[i].Characteristics & IMAGE_SCN_MEM_WRITE)) continue;
 174         if (lseek( shared_fd, pos, SEEK_SET ) != pos) goto error;
 175         pos += ROUND_SIZE( 0, sec[i].Misc.VirtualSize );
 176         if (sec[i].Characteristics & IMAGE_SCN_CNT_UNINITIALIZED_DATA) continue;
 177         if (!sec[i].PointerToRawData || !sec[i].SizeOfRawData) continue;
 178         if (lseek( fd, sec[i].PointerToRawData, SEEK_SET ) != sec[i].PointerToRawData) goto error;
 179         toread = sec[i].SizeOfRawData;
 180         while (toread)
 181         {
 182             long res = read( fd, buffer + sec[i].SizeOfRawData - toread, toread );
 183             if (res <= 0) goto error;
 184             toread -= res;
 185         }
 186         if (write( shared_fd, buffer, sec[i].SizeOfRawData ) != sec[i].SizeOfRawData) goto error;
 187     }
 188     free( buffer );
 189     return 1;
 190
 191  error:
 192     if (buffer) free( buffer );
 193     return 0;
 194 }
 195
 196 /* retrieve the mapping parameters for an executable (PE) image */
 197 static int get_image_params( struct mapping *mapping )
 198 {
 199     IMAGE_DOS_HEADER dos;
 200     IMAGE_NT_HEADERS nt;
 201     IMAGE_SECTION_HEADER *sec = NULL;
 202     int fd, filepos, size;
 203
 204     /* load the headers */
 205
 206     if ((fd = get_mmap_fd( mapping->file )) == -1) return 0;
 207     filepos = lseek( fd, 0, SEEK_SET );
 208     if (read( fd, &dos, sizeof(dos) ) != sizeof(dos)) goto error;
 209     if (dos.e_magic != IMAGE_DOS_SIGNATURE) goto error;
 210     if (lseek( fd, dos.e_lfanew, SEEK_SET ) == -1) goto error;
 211     if (read( fd, &nt, sizeof(nt) ) != sizeof(nt)) goto error;
 212     if (nt.Signature != IMAGE_NT_SIGNATURE) goto error;
 213
 214     /* load the section headers */
 215
 216     size = sizeof(*sec) * nt.FileHeader.NumberOfSections;
 217     if (!(sec = malloc( size ))) goto error;
 218     if (read( fd, sec, size ) != size) goto error;
 219
 220     if (!build_shared_mapping( mapping, fd, sec, nt.FileHeader.NumberOfSections )) goto error;
 221
 222     if (mapping->shared_file)  /* link it in the list */
 223     {
 224         if ((mapping->shared_next = shared_first)) shared_first->shared_prev = mapping;
 225         mapping->shared_prev = NULL;
 226         shared_first = mapping;
 227     }
 228
 229     mapping->size_low    = ROUND_SIZE( 0, nt.OptionalHeader.SizeOfImage );
 230     mapping->size_high   = 0;
 231     mapping->base        = (void *)nt.OptionalHeader.ImageBase;
 232     mapping->header_size = ROUND_SIZE( mapping->base, nt.OptionalHeader.SizeOfHeaders );
 233     mapping->protect     = VPROT_IMAGE;
 234
 235     /* sanity check */
 236     if (mapping->header_size > mapping->size_low) goto error;
 237
 238     lseek( fd, filepos, SEEK_SET );
 239     free( sec );
 240     return 1;
 241
 242  error:
 243     lseek( fd, filepos, SEEK_SET );
 244     if (sec) free( sec );
 245     set_error( STATUS_INVALID_FILE_FOR_SECTION );
 246     return 0;
 247 }
 248
 249
 250 static struct object *create_mapping( int size_high, int size_low, int protect,
 251                                       handle_t handle, const WCHAR *name, size_t len )
 252 {
 253     struct mapping *mapping;
 254     int access = 0;
 255
 256     if (!page_mask) init_page_size();
 257
 258     if (!(mapping = create_named_object( &mapping_ops, name, len )))
 259         return NULL;
 260     if (get_error() == STATUS_OBJECT_NAME_COLLISION)
 261         return &mapping->obj;  /* Nothing else to do */
 262
 263     mapping->header_size = 0;
 264     mapping->base        = NULL;
 265     mapping->shared_file = NULL;
 266     mapping->shared_size = 0;
 267
 268     if (protect & VPROT_READ) access |= GENERIC_READ;
 269     if (protect & VPROT_WRITE) access |= GENERIC_WRITE;
 270
 271     if (handle)
 272     {
 273         if (!(mapping->file = get_file_obj( current->process, handle, access ))) goto error;
 274         if (protect & VPROT_IMAGE)
 275         {
 276             if (!get_image_params( mapping )) goto error;
 277             return &mapping->obj;
 278         }
 279         if (!size_high && !size_low)
 280         {
 281             int flags;
 282             struct get_file_info_reply reply;
 283             struct object *obj = (struct object *)mapping->file;
 284             obj->ops->get_file_info( obj, &reply, &flags );
 285             size_high = reply.size_high;
 286             size_low  = ROUND_SIZE( 0, reply.size_low );
 287         }
 288         else if (!grow_file( mapping->file, size_high, size_low )) goto error;
 289     }
 290     else  /* Anonymous mapping (no associated file) */
 291     {
 292         if ((!size_high && !size_low) || (protect & VPROT_IMAGE))
 293         {
 294             set_error( STATUS_INVALID_PARAMETER );
 295             mapping->file = NULL;
 296             goto error;
 297         }
 298         if (!(mapping->file = create_temp_file( access ))) goto error;
 299         if (!grow_file( mapping->file, size_high, size_low )) goto error;
 300     }
 301     mapping->size_high = size_high;
 302     mapping->size_low  = ROUND_SIZE( 0, size_low );
 303     mapping->protect   = protect;
 304     return &mapping->obj;
 305
 306  error:
 307     release_object( mapping );
 308     return NULL;
 309 }
 310
 311 static void mapping_dump( struct object *obj, int verbose )
 312 {
 313     struct mapping *mapping = (struct mapping *)obj;
 314     assert( obj->ops == &mapping_ops );
 315     fprintf( stderr, "Mapping size=%08x%08x prot=%08x file=%p header_size=%08x base=%p "
 316              "shared_file=%p shared_size=%08x ",
 317              mapping->size_high, mapping->size_low, mapping->protect, mapping->file,
 318              mapping->header_size, mapping->base, mapping->shared_file, mapping->shared_size );
 319     dump_object_name( &mapping->obj );
 320     fputc( '\n', stderr );
 321 }
 322
 323 static int mapping_get_fd( struct object *obj )
 324 {
 325     struct mapping *mapping = (struct mapping *)obj;
 326     assert( obj->ops == &mapping_ops );
 327     return get_mmap_fd( mapping->file );
 328 }
 329
 330 static int mapping_get_info( struct object *obj, struct get_file_info_reply *reply, int *flags )
 331 {
 332     struct mapping *mapping = (struct mapping *)obj;
 333     struct object *file = (struct object *)mapping->file;
 334
 335     assert( obj->ops == &mapping_ops );
 336     assert( file );
 337     return file->ops->get_file_info( file, reply, flags );
 338 }
 339
 340 static void mapping_destroy( struct object *obj )
 341 {
 342     struct mapping *mapping = (struct mapping *)obj;
 343     assert( obj->ops == &mapping_ops );
 344     if (mapping->file) release_object( mapping->file );
 345     if (mapping->shared_file)
 346     {
 347         release_object( mapping->shared_file );
 348         if (mapping->shared_next) mapping->shared_next->shared_prev = mapping->shared_prev;
 349         if (mapping->shared_prev) mapping->shared_prev->shared_next = mapping->shared_next;
 350         else shared_first = mapping->shared_next;
 351     }
 352 }
 353
 354 int get_page_size(void)
 355 {
 356     if (!page_mask) init_page_size();
 357     return page_mask + 1;
 358 }
 359
 360 /* create a file mapping */
 361 DECL_HANDLER(create_mapping)
 362 {
 363     struct object *obj;
 364
 365     reply->handle = 0;
 366     if ((obj = create_mapping( req->size_high, req->size_low,
 367                                req->protect, req->file_handle,
 368                                get_req_data(), get_req_data_size() )))
 369     {
 370         int access = FILE_MAP_ALL_ACCESS;
 371         if (!(req->protect & VPROT_WRITE)) access &= ~FILE_MAP_WRITE;
 372         reply->handle = alloc_handle( current->process, obj, access, req->inherit );
 373         release_object( obj );
 374     }
 375 }
 376
 377 /* open a handle to a mapping */
 378 DECL_HANDLER(open_mapping)
 379 {
 380     reply->handle = open_object( get_req_data(), get_req_data_size(),
 381                                  &mapping_ops, req->access, req->inherit );
 382 }
 383
 384 /* get a mapping information */
 385 DECL_HANDLER(get_mapping_info)
 386 {
 387     struct mapping *mapping;
 388
 389     if ((mapping = (struct mapping *)get_handle_obj( current->process, req->handle,
 390                                                      0, &mapping_ops )))
 391     {
 392         reply->size_high   = mapping->size_high;
 393         reply->size_low    = mapping->size_low;
 394         reply->protect     = mapping->protect;
 395         reply->header_size = mapping->header_size;
 396         reply->base        = mapping->base;
 397         reply->shared_file = 0;
 398         reply->shared_size = mapping->shared_size;
 399         reply->drive_type  = get_file_drive_type( mapping->file );
 400         if (mapping->shared_file)
 401             reply->shared_file = alloc_handle( current->process, mapping->shared_file,
 402                                                GENERIC_READ|GENERIC_WRITE, 0 );
 403         release_object( mapping );
 404     }
 405 }