source3/smbd/mangle.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Name mangling interface
   4    Copyright (C) Andrew Tridgell 2002
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program 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
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21 #include "includes.h"
  22
  23 static struct mangle_fns *mangle_fns;
  24
  25 /* this allows us to add more mangling backends */
  26 static const struct {
  27         const char *name;
  28         struct mangle_fns *(*init_fn)(void);
  29 } mangle_backends[] = {
  30         { "hash", mangle_hash_init },
  31         { "hash2", mangle_hash2_init },
  32         { "posix", posix_mangle_init },
  33         /*{ "tdb", mangle_tdb_init }, */
  34         { NULL, NULL }
  35 };
  36
  37 /*
  38   initialise the mangling subsystem
  39 */
  40 static void mangle_init(void)
  41 {
  42         int i;
  43         const char *method;
  44
  45         if (mangle_fns)
  46                 return;
  47
  48         method = lp_mangling_method();
  49
  50         /* find the first mangling method that manages to initialise and
  51            matches the "mangling method" parameter */
  52         for (i=0; mangle_backends[i].name && !mangle_fns; i++) {
  53                 if (!method || !*method || strcmp(method, mangle_backends[i].name) == 0) {
  54                         mangle_fns = mangle_backends[i].init_fn();
  55                 }
  56         }
  57
  58         if (!mangle_fns) {
  59                 DEBUG(0,("Failed to initialise mangling system '%s'\n", method));
  60                 exit_server("mangling init failed");
  61         }
  62 }
  63
  64
  65 /*
  66   reset the cache. This is called when smb.conf has been reloaded
  67 */
  68 void mangle_reset_cache(void)
  69 {
  70         mangle_init();
  71         mangle_fns->reset();
  72 }
  73
  74 void mangle_change_to_posix(void)
  75 {
  76         mangle_fns = NULL;
  77         lp_set_mangling_method("posix");
  78         mangle_reset_cache();
  79 }
  80
  81 /*
  82   see if a filename has come out of our mangling code
  83 */
  84 BOOL mangle_is_mangled(const char *s, int snum)
  85 {
  86         return mangle_fns->is_mangled(s, snum);
  87 }
  88
  89 /*
  90   see if a filename matches the rules of a 8.3 filename
  91 */
  92 BOOL mangle_is_8_3(const char *fname, BOOL check_case, int snum)
  93 {
  94         return mangle_fns->is_8_3(fname, check_case, False, snum);
  95 }
  96
  97 BOOL mangle_is_8_3_wildcards(const char *fname, BOOL check_case, int snum)
  98 {
  99         return mangle_fns->is_8_3(fname, check_case, True, snum);
 100 }
 101
 102 /*
 103   try to reverse map a 8.3 name to the original filename. This doesn't have to
 104   always succeed, as the directory handling code in smbd will scan the directory
 105   looking for a matching name if it doesn't. It should succeed most of the time
 106   or there will be a huge performance penalty
 107 */
 108 BOOL mangle_check_cache(char *s, size_t maxlen, int snum)
 109 {
 110         return mangle_fns->check_cache(s, maxlen, snum);
 111 }
 112
 113 /*
 114    map a long filename to a 8.3 name.
 115  */
 116
 117 void mangle_map(pstring OutName, BOOL need83, BOOL cache83, int snum)
 118 {
 119         /* name mangling can be disabled for speed, in which case
 120            we just truncate the string */
 121         if (!lp_manglednames(snum)) {
 122                 if (need83) {
 123                         string_truncate(OutName, 12);
 124                 }
 125                 return;
 126         }
 127
 128         /* invoke the inane "mangled map" code */
 129         mangle_map_filename(OutName, snum);
 130         mangle_fns->name_map(OutName, need83, cache83, lp_defaultcase(snum), snum);
 131 }