source: vendor/current/source3/smbd/mangle.c

/*
   Unix SMB/CIFS implementation.
   Name mangling interface
   Copyright (C) Andrew Tridgell 2002

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "includes.h"
#include "smbd/smbd.h"
#include "smbd/globals.h"
#include "mangle.h"

/* this allows us to add more mangling backends */
static const struct {
        const char *name;
        const struct mangle_fns *(*init_fn)(void);
} mangle_backends[] = {
        { "hash", mangle_hash_init },
        { "hash2", mangle_hash2_init },
        { "posix", posix_mangle_init },
        /*{ "tdb", mangle_tdb_init }, */
        { NULL, NULL }
};

/*
  initialise the mangling subsystem
*/
static void mangle_init(void)
{
        int i;
        const char *method;

        if (mangle_fns)
                return;

        method = lp_mangling_method(talloc_tos());

        /* find the first mangling method that manages to initialise and
           matches the "mangling method" parameter */
        for (i=0; mangle_backends[i].name && !mangle_fns; i++) {
                if (!method || !*method || strcmp(method, mangle_backends[i].name) == 0) {
                        mangle_fns = mangle_backends[i].init_fn();
                }
        }

        if (!mangle_fns) {
                DEBUG(0,("Failed to initialise mangling system '%s'\n", method));
                exit_server("mangling init failed");
        }
}


/*
  reset the cache. This is called when smb.conf has been reloaded
*/
void mangle_reset_cache(void)
{
        mangle_init();
        mangle_fns->reset();
}

void mangle_change_to_posix(void)
{
        mangle_fns = NULL;
        lp_set_mangling_method("posix");
        mangle_reset_cache();
}

/*
  see if a filename has come out of our mangling code
*/
bool mangle_is_mangled(const char *s, const struct share_params *p)
{
        return mangle_fns->is_mangled(s, p);
}

/*
  see if a filename matches the rules of a 8.3 filename
*/
bool mangle_is_8_3(const char *fname, bool check_case,
                   const struct share_params *p)
{
        return mangle_fns->is_8_3(fname, check_case, False, p);
}

bool mangle_is_8_3_wildcards(const char *fname, bool check_case,
                             const struct share_params *p)
{
        return mangle_fns->is_8_3(fname, check_case, True, p);
}

bool mangle_must_mangle(const char *fname,
                   const struct share_params *p)
{
        if (!lp_mangled_names(p)) {
                return False;
        }
        return mangle_fns->must_mangle(fname, p);
}

/*
  try to reverse map a 8.3 name to the original filename. This doesn't have to
  always succeed, as the directory handling code in smbd will scan the directory
  looking for a matching name if it doesn't. It should succeed most of the time
  or there will be a huge performance penalty
*/
bool mangle_lookup_name_from_8_3(TALLOC_CTX *ctx,
                        const char *in,
                        char **out, /* talloced on the given context. */
                        const struct share_params *p)
{
        return mangle_fns->lookup_name_from_8_3(ctx, in, out, p);
}

/*
   mangle a long filename to a 8.3 name.
   Return True if we did mangle the name (ie. out is filled in).
   False on error.
   JRA.
 */

bool name_to_8_3(const char *in,
                char out[13],
                bool cache83,
                const struct share_params *p)
{
        memset(out,'\0',13);

        /* name mangling can be disabled for speed, in which case
           we just truncate the string */
        if (!lp_mangled_names(p)) {
                strlcpy(out, in, 13);
                return True;
        }

        return mangle_fns->name_to_8_3(in,
                                out,
                                cache83,
                                lp_default_case(p->service),
                                p);
}