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 #include "mangle.h"
  23
  24 /* this allows us to add more mangling backends */
  25 static const struct {
  26         const char *name;
  27         const struct mangle_fns *(*init_fn)(void);
  28 } mangle_backends[] = {
  29         { "hash", mangle_hash_init },
  30         { "hash2", mangle_hash2_init },
  31         { "posix", posix_mangle_init },
  32         /*{ "tdb", mangle_tdb_init }, */
  33         { NULL, NULL }
  34 };
  35
  36 /*
  37   initialise the mangling subsystem
  38 */
  39 static void mangle_init(void)
  40 {
  41         int i;
  42         const char *method;
  43
  44         if (mangle_fns)
  45                 return;
  46
  47         method = lp_mangling_method();
  48
  49         /* find the first mangling method that manages to initialise and
  50            matches the "mangling method" parameter */
  51         for (i=0; mangle_backends[i].name && !mangle_fns; i++) {
  52                 if (!method || !*method || strcmp(method, mangle_backends[i].name) == 0) {
  53                         mangle_fns = mangle_backends[i].init_fn();
  54                 }
  55         }
  56
  57         if (!mangle_fns) {
  58                 DEBUG(0,("Failed to initialise mangling system '%s'\n", method));
  59                 exit_server("mangling init failed");
  60         }
  61 }
  62
  63
  64 /*
  65   reset the cache. This is called when smb.conf has been reloaded
  66 */
  67 void mangle_reset_cache(void)
  68 {
  69         mangle_init();
  70         mangle_fns->reset();
  71 }
  72
  73 void mangle_change_to_posix(void)
  74 {
  75         mangle_fns = NULL;
  76         lp_set_mangling_method("posix");
  77         mangle_reset_cache();
  78 }
  79
  80 /*
  81   see if a filename has come out of our mangling code
  82 */
  83 bool mangle_is_mangled(const char *s, const struct share_params *p)
  84 {
  85         return mangle_fns->is_mangled(s, p);
  86 }
  87
  88 /*
  89   see if a filename matches the rules of a 8.3 filename
  90 */
  91 bool mangle_is_8_3(const char *fname, bool check_case,
  92                    const struct share_params *p)
  93 {
  94         return mangle_fns->is_8_3(fname, check_case, False, p);
  95 }
  96
  97 bool mangle_is_8_3_wildcards(const char *fname, bool check_case,
  98                              const struct share_params *p)
  99 {
 100         return mangle_fns->is_8_3(fname, check_case, True, p);
 101 }
 102
 103 bool mangle_must_mangle(const char *fname,
 104                    const struct share_params *p)
 105 {
 106         if (!lp_manglednames(p)) {
 107                 return False;
 108         }
 109         return mangle_fns->must_mangle(fname, p);
 110 }
 111
 112 /*
 113   try to reverse map a 8.3 name to the original filename. This doesn't have to
 114   always succeed, as the directory handling code in smbd will scan the directory
 115   looking for a matching name if it doesn't. It should succeed most of the time
 116   or there will be a huge performance penalty
 117 */
 118 bool mangle_lookup_name_from_8_3(TALLOC_CTX *ctx,
 119                         const char *in,
 120                         char **out, /* talloced on the given context. */
 121                         const struct share_params *p)
 122 {
 123         return mangle_fns->lookup_name_from_8_3(ctx, in, out, p);
 124 }
 125
 126 /*
 127    mangle a long filename to a 8.3 name.
 128    Return True if we did mangle the name (ie. out is filled in).
 129    False on error.
 130    JRA.
 131  */
 132
 133 bool name_to_8_3(const char *in,
 134                 char out[13],
 135                 bool cache83,
 136                 const struct share_params *p)
 137 {
 138         memset(out,'\0',13);
 139
 140         /* name mangling can be disabled for speed, in which case
 141            we just truncate the string */
 142         if (!lp_manglednames(p)) {
 143                 strlcpy(out, in, 13);
 144                 return True;
 145         }
 146
 147         return mangle_fns->name_to_8_3(in,
 148                                 out,
 149                                 cache83,
 150                                 lp_defaultcase(p->service),
 151                                 p);
 152 }