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 3 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, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "includes.h"
  21 #include "smbd/globals.h"
  22
  23 /* this allows us to add more mangling backends */
  24 static const struct {
  25         const char *name;
  26         const struct mangle_fns *(*init_fn)(void);
  27 } mangle_backends[] = {
  28         { "hash", mangle_hash_init },
  29         { "hash2", mangle_hash2_init },
  30         { "posix", posix_mangle_init },
  31         /*{ "tdb", mangle_tdb_init }, */
  32         { NULL, NULL }
  33 };
  34
  35 /*
  36   initialise the mangling subsystem
  37 */
  38 static void mangle_init(void)
  39 {
  40         int i;
  41         const 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         mangle_fns->reset();
  70 }
  71
  72 void mangle_change_to_posix(void)
  73 {
  74         mangle_fns = NULL;
  75         lp_set_mangling_method("posix");
  76         mangle_reset_cache();
  77 }
  78
  79 /*
  80   see if a filename has come out of our mangling code
  81 */
  82 bool mangle_is_mangled(const char *s, const struct share_params *p)
  83 {
  84         return mangle_fns->is_mangled(s, p);
  85 }
  86
  87 /*
  88   see if a filename matches the rules of a 8.3 filename
  89 */
  90 bool mangle_is_8_3(const char *fname, bool check_case,
  91                    const struct share_params *p)
  92 {
  93         return mangle_fns->is_8_3(fname, check_case, False, p);
  94 }
  95
  96 bool mangle_is_8_3_wildcards(const char *fname, bool check_case,
  97                              const struct share_params *p)
  98 {
  99         return mangle_fns->is_8_3(fname, check_case, True, p);
 100 }
 101
 102 bool mangle_must_mangle(const char *fname,
 103                    const struct share_params *p)
 104 {
 105         if (!lp_manglednames(p)) {
 106                 return False;
 107         }
 108         return mangle_fns->must_mangle(fname, p);
 109 }
 110
 111 /*
 112   try to reverse map a 8.3 name to the original filename. This doesn't have to
 113   always succeed, as the directory handling code in smbd will scan the directory
 114   looking for a matching name if it doesn't. It should succeed most of the time
 115   or there will be a huge performance penalty
 116 */
 117 bool mangle_lookup_name_from_8_3(TALLOC_CTX *ctx,
 118                         const char *in,
 119                         char **out, /* talloced on the given context. */
 120                         const struct share_params *p)
 121 {
 122         return mangle_fns->lookup_name_from_8_3(ctx, in, out, p);
 123 }
 124
 125 /*
 126    mangle a long filename to a 8.3 name.
 127    Return True if we did mangle the name (ie. out is filled in).
 128    False on error.
 129    JRA.
 130  */
 131
 132 bool name_to_8_3(const char *in,
 133                 char out[13],
 134                 bool cache83,
 135                 const struct share_params *p)
 136 {
 137         memset(out,'\0',13);
 138
 139         /* name mangling can be disabled for speed, in which case
 140            we just truncate the string */
 141         if (!lp_manglednames(p)) {
 142                 strlcpy(out, in, 13);
 143                 return True;
 144         }
 145
 146         return mangle_fns->name_to_8_3(in,
 147                                 out,
 148                                 cache83,
 149                                 lp_defaultcase(p->service),
 150                                 p);
 151 }