source/smbd/filename.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    filename handling routines
   4    Copyright (C) Andrew Tridgell 1992-1998
   5    Copyright (C) Jeremy Allison 1999-2004
   6    Copyright (C) Ying Chen 2000
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21 */
  22
  23 /*
  24  * New hash table stat cache code added by Ying Chen.
  25  */
  26
  27 #include "includes.h"
  28
  29 static BOOL scan_directory(connection_struct *conn, const char *path, char *name,size_t maxlength);
  30
  31 /****************************************************************************
  32  Check if two filenames are equal.
  33  This needs to be careful about whether we are case sensitive.
  34 ****************************************************************************/
  35
  36 static BOOL fname_equal(const char *name1, const char *name2, BOOL case_sensitive)
  37 {
  38         /* Normal filename handling */
  39         if (case_sensitive)
  40                 return(strcmp(name1,name2) == 0);
  41
  42         return(strequal(name1,name2));
  43 }
  44
  45 /****************************************************************************
  46  Mangle the 2nd name and check if it is then equal to the first name.
  47 ****************************************************************************/
  48
  49 static BOOL mangled_equal(const char *name1, const char *name2,
  50                           const struct share_params *p)
  51 {
  52         pstring tmpname;
  53
  54         pstrcpy(tmpname, name2);
  55         mangle_map(tmpname, True, False, p);
  56         return strequal(name1, tmpname);
  57 }
  58
  59 /****************************************************************************
  60 This routine is called to convert names from the dos namespace to unix
  61 namespace. It needs to handle any case conversions, mangling, format
  62 changes etc.
  63
  64 We assume that we have already done a chdir() to the right "root" directory
  65 for this service.
  66
  67 The function will return False if some part of the name except for the last
  68 part cannot be resolved
  69
  70 If the saved_last_component != 0, then the unmodified last component
  71 of the pathname is returned there. This is used in an exceptional
  72 case in reply_mv (so far). If saved_last_component == 0 then nothing
  73 is returned there.
  74
  75 The bad_path arg is set to True if the filename walk failed. This is
  76 used to pick the correct error code to return between ENOENT and ENOTDIR
  77 as Windows applications depend on ERRbadpath being returned if a component
  78 of a pathname does not exist.
  79
  80 On exit from unix_convert, if *pst was not null, then the file stat
  81 struct will be returned if the file exists and was found, if not this
  82 stat struct will be filled with zeros (and this can be detected by checking
  83 for nlinks = 0, which can never be true for any file).
  84 ****************************************************************************/
  85
  86 BOOL unix_convert(pstring name,connection_struct *conn,char *saved_last_component,
  87                   BOOL *bad_path, SMB_STRUCT_STAT *pst)
  88 {
  89         SMB_STRUCT_STAT st;
  90         char *start, *end;
  91         pstring dirpath;
  92         pstring orig_path;
  93         BOOL component_was_mangled = False;
  94         BOOL name_has_wildcard = False;
  95
  96         SET_STAT_INVALID(*pst);
  97
  98         *dirpath = 0;
  99         *bad_path = False;
 100         if(saved_last_component)
 101                 *saved_last_component = 0;
 102
 103         if (conn->printer) {
 104                 /* we don't ever use the filenames on a printer share as a
 105                         filename - so don't convert them */
 106                 return True;
 107         }
 108
 109         DEBUG(5, ("unix_convert called on file \"%s\"\n", name));
 110
 111         /*
 112          * Conversion to basic unix format is already done in check_path_syntax().
 113          */
 114
 115         /*
 116          * Names must be relative to the root of the service - any leading /.
 117          * and trailing /'s should have been trimmed by check_path_syntax().
 118          */
 119
 120 #ifdef DEVELOPER
 121         SMB_ASSERT(*name != '/');
 122 #endif
 123
 124         /*
 125          * If we trimmed down to a single '\0' character
 126          * then we should use the "." directory to avoid
 127          * searching the cache, but not if we are in a
 128          * printing share.
 129          * As we know this is valid we can return true here.
 130          */
 131
 132         if (!*name) {
 133                 name[0] = '.';
 134                 name[1] = '\0';
 135                 if (SMB_VFS_STAT(conn,name,&st) == 0) {
 136                         *pst = st;
 137                 }
 138                 DEBUG(5,("conversion finished \"\" -> %s\n",name));
 139                 return(True);
 140         }
 141
 142         /*
 143          * Ensure saved_last_component is valid even if file exists.
 144          */
 145
 146         if(saved_last_component) {
 147                 end = strrchr_m(name, '/');
 148                 if(end)
 149                         pstrcpy(saved_last_component, end + 1);
 150                 else
 151                         pstrcpy(saved_last_component, name);
 152         }
 153
 154         /*
 155          * Large directory fix normalization. If we're case sensitive, and
 156          * the case preserving parameters are set to "no", normalize the case of
 157          * the incoming filename from the client WHETHER IT EXISTS OR NOT !
 158          * This is in conflict with the current (3.0.20) man page, but is
 159          * what people expect from the "large directory howto". I'll update
 160          * the man page. Thanks to jht@samba.org for finding this. JRA.
 161          */
 162
 163         if (conn->case_sensitive && !conn->case_preserve && !conn->short_case_preserve) {
 164                 strnorm(name, lp_defaultcase(SNUM(conn)));
 165         }
 166
 167         start = name;
 168         pstrcpy(orig_path, name);
 169
 170         if(!conn->case_sensitive && stat_cache_lookup(conn, name, dirpath, &start, &st)) {
 171                 *pst = st;
 172                 return True;
 173         }
 174
 175         /*
 176          * stat the name - if it exists then we are all done!
 177          */
 178
 179         if (SMB_VFS_STAT(conn,name,&st) == 0) {
 180                 stat_cache_add(orig_path, name, conn->case_sensitive);
 181                 DEBUG(5,("conversion finished %s -> %s\n",orig_path, name));
 182                 *pst = st;
 183                 return(True);
 184         }
 185
 186         DEBUG(5,("unix_convert begin: name = %s, dirpath = %s, start = %s\n", name, dirpath, start));
 187
 188         /*
 189          * A special case - if we don't have any mangling chars and are case
 190          * sensitive then searching won't help.
 191          */
 192
 193         if (conn->case_sensitive && !mangle_is_mangled(name, conn->params) &&
 194             !*lp_mangled_map(conn->params))
 195                 return(False);
 196
 197         name_has_wildcard = ms_has_wild(start);
 198
 199         /*
 200          * is_mangled() was changed to look at an entire pathname, not
 201          * just a component. JRA.
 202          */
 203
 204         if (mangle_is_mangled(start, conn->params))
 205                 component_was_mangled = True;
 206
 207         /*
 208          * Now we need to recursively match the name against the real
 209          * directory structure.
 210          */
 211
 212         /*
 213          * Match each part of the path name separately, trying the names
 214          * as is first, then trying to scan the directory for matching names.
 215          */
 216
 217         for (; start ; start = (end?end+1:(char *)NULL)) {
 218                 /*
 219                  * Pinpoint the end of this section of the filename.
 220                  */
 221                 end = strchr_m(start, '/');
 222
 223                 /*
 224                  * Chop the name at this point.
 225                  */
 226                 if (end)
 227                         *end = 0;
 228
 229                 if(saved_last_component != 0)
 230                         pstrcpy(saved_last_component, end ? end + 1 : start);
 231
 232                 /*
 233                  * Check if the name exists up to this point.
 234                  */
 235
 236                 if (SMB_VFS_STAT(conn,name, &st) == 0) {
 237                         /*
 238                          * It exists. it must either be a directory or this must be
 239                          * the last part of the path for it to be OK.
 240                          */
 241                         if (end && !(st.st_mode & S_IFDIR)) {
 242                                 /*
 243                                  * An intermediate part of the name isn't a directory.
 244                                  */
 245                                 DEBUG(5,("Not a dir %s\n",start));
 246                                 *end = '/';
 247                                 /*
 248                                  * We need to return the fact that the intermediate
 249                                  * name resolution failed. This is used to return an
 250                                  * error of ERRbadpath rather than ERRbadfile. Some
 251                                  * Windows applications depend on the difference between
 252                                  * these two errors.
 253                                  */
 254                                 errno = ENOTDIR;
 255                                 *bad_path = True;
 256                                 return(False);
 257                         }
 258
 259                         if (!end) {
 260                                 /*
 261                                  * We just scanned for, and found the end of the path.
 262                                  * We must return the valid stat struct.
 263                                  * JRA.
 264                                  */
 265
 266                                 *pst = st;
 267                         }
 268
 269                 } else {
 270                         pstring rest;
 271
 272                         /* Stat failed - ensure we don't use it. */
 273                         SET_STAT_INVALID(st);
 274                         *rest = 0;
 275
 276                         /*
 277                          * Remember the rest of the pathname so it can be restored
 278                          * later.
 279                          */
 280
 281                         if (end)
 282                                 pstrcpy(rest,end+1);
 283
 284                         /* Reset errno so we can detect directory open errors. */
 285                         errno = 0;
 286
 287                         /*
 288                          * Try to find this part of the path in the directory.
 289                          */
 290
 291                         if (ms_has_wild(start) ||
 292                             !scan_directory(conn, dirpath, start, sizeof(pstring) - 1 - (start - name))) {
 293                                 if (end) {
 294                                         /*
 295                                          * An intermediate part of the name can't be found.
 296                                          */
 297                                         DEBUG(5,("Intermediate not found %s\n",start));
 298                                         *end = '/';
 299
 300                                         /*
 301                                          * We need to return the fact that the intermediate
 302                                          * name resolution failed. This is used to return an
 303                                          * error of ERRbadpath rather than ERRbadfile. Some
 304                                          * Windows applications depend on the difference between
 305                                          * these two errors.
 306                                          */
 307                                         *bad_path = True;
 308                                         return(False);
 309                                 }
 310
 311                                 if (errno == ENOTDIR) {
 312                                         *bad_path = True;
 313                                         return(False);
 314                                 }
 315
 316                                 /*
 317                                  * Just the last part of the name doesn't exist.
 318                                  * We need to strupper() or strlower() it as
 319                                  * this conversion may be used for file creation
 320                                  * purposes. Fix inspired by Thomas Neumann <t.neumann@iku-ag.de>.
 321                                  */
 322                                 if (!conn->case_preserve ||
 323                                     (mangle_is_8_3(start, False, conn->params) &&
 324                                                  !conn->short_case_preserve)) {
 325                                         strnorm(start, lp_defaultcase(SNUM(conn)));
 326                                 }
 327
 328                                 /*
 329                                  * check on the mangled stack to see if we can recover the
 330                                  * base of the filename.
 331                                  */
 332
 333                                 if (mangle_is_mangled(start, conn->params)) {
 334                                         mangle_check_cache( start, sizeof(pstring) - 1 - (start - name), conn->params);
 335                                 }
 336
 337                                 DEBUG(5,("New file %s\n",start));
 338                                 return(True);
 339                         }
 340
 341                         /*
 342                          * Restore the rest of the string. If the string was mangled the size
 343                          * may have changed.
 344                          */
 345                         if (end) {
 346                                 end = start + strlen(start);
 347                                 if (!safe_strcat(start, "/", sizeof(pstring) - 1 - (start - name)) ||
 348                                     !safe_strcat(start, rest, sizeof(pstring) - 1 - (start - name))) {
 349                                         return False;
 350                                 }
 351                                 *end = '\0';
 352                         } else {
 353                                 /*
 354                                  * We just scanned for, and found the end of the path.
 355                                  * We must return a valid stat struct if it exists.
 356                                  * JRA.
 357                                  */
 358
 359                                 if (SMB_VFS_STAT(conn,name, &st) == 0) {
 360                                         *pst = st;
 361                                 } else {
 362                                         SET_STAT_INVALID(st);
 363                                 }
 364                         }
 365                 } /* end else */
 366
 367                 /*
 368                  * Add to the dirpath that we have resolved so far.
 369                  */
 370                 if (*dirpath)
 371                         pstrcat(dirpath,"/");
 372
 373                 pstrcat(dirpath,start);
 374
 375                 /*
 376                  * Don't cache a name with mangled or wildcard components
 377                  * as this can change the size.
 378                  */
 379
 380                 if(!component_was_mangled && !name_has_wildcard)
 381                         stat_cache_add(orig_path, dirpath, conn->case_sensitive);
 382
 383                 /*
 384                  * Restore the / that we wiped out earlier.
 385                  */
 386                 if (end)
 387                         *end = '/';
 388         }
 389
 390         /*
 391          * Don't cache a name with mangled or wildcard components
 392          * as this can change the size.
 393          */
 394
 395         if(!component_was_mangled && !name_has_wildcard)
 396                 stat_cache_add(orig_path, name, conn->case_sensitive);
 397
 398         /*
 399          * The name has been resolved.
 400          */
 401
 402         DEBUG(5,("conversion finished %s -> %s\n",orig_path, name));
 403         return(True);
 404 }
 405
 406 /****************************************************************************
 407  Check a filename - possibly caling reducename.
 408  This is called by every routine before it allows an operation on a filename.
 409  It does any final confirmation necessary to ensure that the filename is
 410  a valid one for the user to access.
 411 ****************************************************************************/
 412
 413 BOOL check_name(const pstring name,connection_struct *conn)
 414 {
 415         BOOL ret = True;
 416
 417         if (IS_VETO_PATH(conn, name))  {
 418                 /* Is it not dot or dot dot. */
 419                 if (!((name[0] == '.') && (!name[1] || (name[1] == '.' && !name[2])))) {
 420                         DEBUG(5,("file path name %s vetoed\n",name));
 421                         errno = ENOENT;
 422                         return False;
 423                 }
 424         }
 425
 426         if (!lp_widelinks(SNUM(conn)) || !lp_symlinks(SNUM(conn))) {
 427                 ret = reduce_name(conn,name);
 428         }
 429
 430         if (!ret) {
 431                 DEBUG(5,("check_name on %s failed\n",name));
 432         }
 433
 434         return(ret);
 435 }
 436
 437 /****************************************************************************
 438  Scan a directory to find a filename, matching without case sensitivity.
 439  If the name looks like a mangled name then try via the mangling functions
 440 ****************************************************************************/
 441
 442 static BOOL scan_directory(connection_struct *conn, const char *path, char *name, size_t maxlength)
 443 {
 444         struct smb_Dir *cur_dir;
 445         const char *dname;
 446         BOOL mangled;
 447         long curpos;
 448
 449         mangled = mangle_is_mangled(name, conn->params);
 450
 451         /* handle null paths */
 452         if (*path == 0)
 453                 path = ".";
 454
 455         /*
 456          * The incoming name can be mangled, and if we de-mangle it
 457          * here it will not compare correctly against the filename (name2)
 458          * read from the directory and then mangled by the mangle_map()
 459          * call. We need to mangle both names or neither.
 460          * (JRA).
 461          *
 462          * Fix for bug found by Dina Fine. If in case sensitive mode then
 463          * the mangle cache is no good (3 letter extension could be wrong
 464          * case - so don't demangle in this case - leave as mangled and
 465          * allow the mangling of the directory entry read (which is done
 466          * case insensitively) to match instead. This will lead to more
 467          * false positive matches but we fail completely without it. JRA.
 468          */
 469
 470         if (mangled && !conn->case_sensitive) {
 471                 mangled = !mangle_check_cache( name, maxlength, conn->params);
 472         }
 473
 474         /* open the directory */
 475         if (!(cur_dir = OpenDir(conn, path, NULL, 0))) {
 476                 DEBUG(3,("scan dir didn't open dir [%s]\n",path));
 477                 return(False);
 478         }
 479
 480         /* now scan for matching names */
 481         curpos = 0;
 482         while ((dname = ReadDirName(cur_dir, &curpos))) {
 483
 484                 /* Is it dot or dot dot. */
 485                 if ((dname[0] == '.') && (!dname[1] || (dname[1] == '.' && !dname[2]))) {
 486                         continue;
 487                 }
 488
 489                 /*
 490                  * At this point dname is the unmangled name.
 491                  * name is either mangled or not, depending on the state of the "mangled"
 492                  * variable. JRA.
 493                  */
 494
 495                 /*
 496                  * Check mangled name against mangled name, or unmangled name
 497                  * against unmangled name.
 498                  */
 499
 500                 if ((mangled && mangled_equal(name,dname,conn->params)) || fname_equal(name, dname, conn->case_sensitive)) {
 501                         /* we've found the file, change it's name and return */
 502                         safe_strcpy(name, dname, maxlength);
 503                         CloseDir(cur_dir);
 504                         return(True);
 505                 }
 506         }
 507
 508         CloseDir(cur_dir);
 509         errno = ENOENT;
 510         return(False);
 511 }