source/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 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         { NULL, NULL }
  33 };
  34
  35 /*
  36   initialise the mangling subsystem
  37 */
  38 static void mangle_init(void)
  39 {
  40         int i;
  41         char *method;
  42
  43         if (mangle_fns)
  44                 return;
  45
  46         method = lp_mangling_method();
  47
  48         /* find the first mangling method that manages to initialise and
  49            matches the "mangling method" parameter */
  50         for (i=0; mangle_backends[i].name && !mangle_fns; i++) {
  51                 if (!method || !*method || strcmp(method, mangle_backends[i].name) == 0) {
  52                         mangle_fns = mangle_backends[i].init_fn();
  53                 }
  54         }
  55
  56         if (!mangle_fns) {
  57                 DEBUG(0,("Failed to initialise mangling system '%s'\n", method));
  58                 exit_server("mangling init failed");
  59         }
  60 }
  61
  62
  63 /*
  64   reset the cache. This is called when smb.conf has been reloaded
  65 */
  66 void mangle_reset_cache(void)
  67 {
  68         mangle_init();
  69
  70         mangle_fns->reset();
  71 }
  72
  73 /*
  74   see if a filename has come out of our mangling code
  75 */
  76 BOOL mangle_is_mangled(const char *s)
  77 {
  78         return mangle_fns->is_mangled(s);
  79 }
  80
  81 /*
  82   see if a filename matches the rules of a 8.3 filename
  83 */
  84 BOOL mangle_is_8_3(const char *fname, BOOL check_case)
  85 {
  86         return mangle_fns->is_8_3(fname, check_case, False);
  87 }
  88
  89 BOOL mangle_is_8_3_wildcards(const char *fname, BOOL check_case)
  90 {
  91         return mangle_fns->is_8_3(fname, check_case, True);
  92 }
  93
  94 /*
  95   try to reverse map a 8.3 name to the original filename. This doesn't have to
  96   always succeed, as the directory handling code in smbd will scan the directory
  97   looking for a matching name if it doesn't. It should succeed most of the time
  98   or there will be a huge performance penalty
  99 */
 100 BOOL mangle_check_cache(char *s)
 101 {
 102         return mangle_fns->check_cache(s);
 103 }
 104
 105 /*
 106    map a long filename to a 8.3 name.
 107  */
 108
 109 void mangle_map(char *OutName, BOOL need83, BOOL cache83, int snum)
 110 {
 111         /* name mangling can be disabled for speed, in which case
 112            we just truncate the string */
 113         if (!lp_manglednames(snum)) {
 114                 if (need83) {
 115                         string_truncate(OutName, 12);
 116                 }
 117                 return;
 118         }
 119
 120         /* invoke the inane "mangled map" code */
 121         mangle_map_filename(OutName, snum);
 122         mangle_fns->name_map(OutName, need83, cache83);
 123 }