libmcrypt/lib/mcrypt_modules.c

/*
 * Copyright (C) 1998,1999,2000,2001 Nikos Mavroyanopoulos
 *
 * This library is free software; you can redistribute it and/or modify it 
 * under the terms of the GNU Library General Public License as published 
 * by the Free Software Foundation; either version 2 of the License, or 
 * (at your option) any later version.
 *
 * This library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#ifndef LIBDEFS_H
#define LIBDEFS_H
#include <libdefs.h>
#endif
#include <bzero.h>
#include <mcrypt_internal.h>
#include <xmemory.h>

#ifndef DEBUG
# define fputs(x, y) 
#endif

extern const mcrypt_preloaded mps[];

#define MAX_MOD_SIZE 1024

static int mcrypt_strcmp( const char* str1, const char* str2) {
int i;
int len;
        if (strlen(str1)!=strlen(str2)) return -1;
        len = strlen(str1);

        for (i=0;i<len;i++) {
                if (str1[i]=='_' && str2[i]=='-') continue;
                if (str2[i]=='_' && str1[i]=='-') continue;
                if (str1[i]!=str2[i]) return -1;
        }
        
        return 0;
}

lt_ptr _mcrypt_search_symlist_lib(const char* name) {
int i=0;

        while( mps[i].name!=0 || mps[i].address!=0) {
                if (mps[i].name!=NULL && mps[i].address==NULL) {
                        if (mcrypt_strcmp(name, mps[i].name)==0) {
                                 return (void*) -1;
                        }
                }
                i++;
        }
        return NULL;
}

lt_ptr _mcrypt_search_symlist_sym(mcrypt_dlhandle handle, const char* _name) {
int i=0;
char name[MAX_MOD_SIZE];

        strcpy(name, handle.name);
        
        strcat( name, "_LTX_");
        strcat( name, _name);
        
        while( mps[i].name!=0 || mps[i].address!=0) {
                if (mps[i].name!=NULL) {
                        if (mcrypt_strcmp(name, mps[i].name)==0) {
                                 return mps[i].address;
                        }
                }
                i++;
        }
        return NULL;
}

void mcrypt_dlclose( mcrypt_dlhandle handle) {
void* mod = handle.handle;

        if (mod!=MCRYPT_INTERNAL_HANDLER && mod!=NULL)
                lt_dlclose(mod);
        handle.handle = NULL;
}

lt_ptr mcrypt_dlsym( mcrypt_dlhandle handle, char* str) {
void* mod;

        mod = handle.handle;
        
        if (mod!=MCRYPT_INTERNAL_HANDLER)
                return lt_dlsym(mod, str);
        else
                return _mcrypt_search_symlist_sym(handle, str);

}

WIN32DLL_DEFINE
int mcrypt_module_close(MCRYPT td)
{
        if (td==NULL) return MCRYPT_UNKNOWN_ERROR;
        
        mcrypt_dlclose(td->algorithm_handle);
        mcrypt_dlclose(td->mode_handle);
        if (lt_dlexit() != 0) {
                return MCRYPT_UNKNOWN_ERROR;
        }

        td->m_encrypt = NULL;
        td->a_encrypt = NULL;
        td->a_decrypt = NULL;
        td->m_decrypt = NULL;

        free(td);
        
        return 0;
}


WIN32DLL_DEFINE
void* mcrypt_dlopen ( mcrypt_dlhandle* handle, const char* a_directory, const char *m_directory, const char *filename) {
        
        char paths[1526];

        if (strlen(filename) >= sizeof( handle->name))
                return MCRYPT_FAILED;
        else
                strcpy( handle->name, filename);
                        
        if (_mcrypt_search_symlist_lib(filename)!=NULL) {
                handle->handle = MCRYPT_INTERNAL_HANDLER;
                return handle->handle;
        }

        memset( paths, 0, 1024);
        if (a_directory != NULL) {
                strncat( paths, a_directory, 512);
                strcat( paths, ":");
        }
        if (m_directory != NULL) {
                strncat( paths, m_directory, 512);
                strcat( paths, ":");
        }
        strncat( paths, LIBDIR, 512);

        lt_dlsetsearchpath(paths);

        handle->handle = lt_dlopenext(filename);

        return handle->handle;

}

WIN32DLL_DEFINE
MCRYPT mcrypt_module_open(const char *algorithm,
                          const char *a_directory, const char *mode, 
                          const char *m_directory)
{
        MCRYPT td;
        const char* err;
        void *ret;
        
        td = calloc(1, sizeof(CRYPT_STREAM));
        if (td==NULL) return MCRYPT_FAILED;

        if (lt_dlinit() != 0) {
                return MCRYPT_FAILED;
        }

        ret = mcrypt_dlopen( &td->algorithm_handle, a_directory, m_directory, algorithm);
        if (ret == NULL) {
                err=lt_dlerror();
                if (err!=NULL) {
                        fputs( err, stderr);
                        fputs("\n", stderr);
                }
                free(td);
                lt_dlexit();
                return MCRYPT_FAILED;
        }

        ret = mcrypt_dlopen( &td->mode_handle, a_directory, m_directory, mode);

        if (ret == NULL) {
                err=lt_dlerror();
                if (err!=NULL) {
                        fputs( err, stderr);
                        fputs( "\n", stderr);
                }
                mcrypt_dlclose(td->algorithm_handle);
                free(td);
                lt_dlexit();
                return MCRYPT_FAILED;
        }

        td->a_encrypt = mcrypt_dlsym(td->algorithm_handle, "_mcrypt_encrypt");
        td->a_decrypt = mcrypt_dlsym(td->algorithm_handle, "_mcrypt_decrypt");
        td->m_encrypt = mcrypt_dlsym(td->mode_handle, "_mcrypt");
        td->m_decrypt = mcrypt_dlsym(td->mode_handle, "_mdecrypt");
        td->a_block_size =
            mcrypt_dlsym(td->algorithm_handle, "_mcrypt_get_block_size");

        if (td->a_encrypt == NULL || td->a_decrypt == NULL|| td->m_encrypt == NULL||
                td->m_decrypt == NULL|| td->a_block_size == NULL) {
                err=lt_dlerror();
                if (err!=NULL) {
                        fputs( err, stderr);
                        fputs( "\n", stderr);
                }
                mcrypt_dlclose(td->algorithm_handle);
                free(td);
                lt_dlexit();
                return MCRYPT_FAILED;
        }

        if (mcrypt_enc_is_block_algorithm_mode(td) !=
            mcrypt_enc_is_block_algorithm(td)) {
                mcrypt_module_close(td);
                return MCRYPT_FAILED;
        }

        return td;
}


/* Modules' frontends */

WIN32DLL_DEFINE
int mcrypt_get_size(MCRYPT td)
{
        int (*_mcrypt_get_size) (void);

        const char *error;

        _mcrypt_get_size = mcrypt_dlsym(td->algorithm_handle, "_mcrypt_get_size");
        if (_mcrypt_get_size == NULL) {
                error = lt_dlerror();
                if (error!=NULL) {
                        fputs(error, stderr);
                        fputs("\n", stderr);
                }
                return MCRYPT_UNKNOWN_ERROR;
        }
        return _mcrypt_get_size();
}

WIN32DLL_DEFINE
int mcrypt_mode_get_size(MCRYPT td)
{
        int (*_mcrypt_get_size) (void);

        const char *error;

        _mcrypt_get_size = mcrypt_dlsym(td->mode_handle, "_mcrypt_mode_get_size");
        if (_mcrypt_get_size == NULL) {
                error = lt_dlerror();
                if (error!=NULL) {
                        fputs(error, stderr);
                        fputs("\n", stderr);
                }
                return MCRYPT_UNKNOWN_ERROR;
        }
        return _mcrypt_get_size();
}

WIN32DLL_DEFINE
int mcrypt_set_key(MCRYPT td, void *a, const void *key, int keysize, const void *iv, int e)
{
        int (*__mcrypt_set_key_stream) (void *, const void *, int, const void *, int);
        int (*__mcrypt_set_key_block) (void *, const void *, int);
        const char *error;

        if (mcrypt_enc_is_block_algorithm(td) == 0) {
                /* stream */
                __mcrypt_set_key_stream = mcrypt_dlsym(td->algorithm_handle, "_mcrypt_set_key");
                if (__mcrypt_set_key_stream == NULL) {
                        error = lt_dlerror();
                        if (error!=NULL) {
                                fputs(error, stderr);
                                fputs("\n", stderr);
                        }
                        return -2;
                }
                return __mcrypt_set_key_stream(a, key, keysize, iv, e);
        } else {
                __mcrypt_set_key_block = mcrypt_dlsym(td->algorithm_handle, "_mcrypt_set_key");
                if (__mcrypt_set_key_block == NULL) {
                        error = lt_dlerror();
                        if (error!=NULL) {
                                fputs(error, stderr);
                                fputs("\n", stderr);
                        }
                        return -2;
                }
                return __mcrypt_set_key_block(a, key, keysize);
        }
}

WIN32DLL_DEFINE
int mcrypt_enc_set_state(MCRYPT td, const void *iv, int size)
{
        int (*__mcrypt_set_state) (void *, const void *, int);
        const char *error;

        __mcrypt_set_state = mcrypt_dlsym(td->mode_handle, "_mcrypt_set_state");
        if (__mcrypt_set_state==NULL) {
                error = lt_dlerror();
                if (error!=NULL) {
                        fputs(error, stderr);
                        fputs("\n", stderr);
                }
                return MCRYPT_UNKNOWN_ERROR;
        }
        return __mcrypt_set_state(td->abuf, iv, size);
}

WIN32DLL_DEFINE
int mcrypt_enc_get_state(MCRYPT td, void *iv, int *size)
{
        int (*__mcrypt_get_state) (void *, void *, int*);
        const char *error;

        __mcrypt_get_state = mcrypt_dlsym(td->mode_handle, "_mcrypt_get_state");
        if (__mcrypt_get_state==NULL) {
                error = lt_dlerror();
                if (error!=NULL) {
                        fputs(error, stderr);
                        fputs("\n", stderr);
                }
                return MCRYPT_UNKNOWN_ERROR;
        }
        return __mcrypt_get_state(td->abuf, iv, size);
}


WIN32DLL_DEFINE
int mcrypt_enc_get_block_size(MCRYPT td)
{
        int (*_mcrypt_get_block_size) (void);

        _mcrypt_get_block_size = td->a_block_size;
        return _mcrypt_get_block_size();
}

WIN32DLL_DEFINE
int mcrypt_get_algo_iv_size(MCRYPT td)
{
        const char* error;
        int (*_mcrypt_get_algo_iv_size) (void);

        _mcrypt_get_algo_iv_size = mcrypt_dlsym(td->algorithm_handle, "_mcrypt_get_algo_iv_size");
        if (_mcrypt_get_algo_iv_size == NULL) {
                error = lt_dlerror();
                if (error!=NULL) {
                        fputs(error, stderr);
                        fputs("\n", stderr);
                }
                return MCRYPT_UNKNOWN_ERROR;
        }
        return _mcrypt_get_algo_iv_size();
}

WIN32DLL_DEFINE
int mcrypt_enc_get_iv_size(MCRYPT td)
{
        if (mcrypt_enc_is_block_algorithm_mode(td) == 1) {
                return mcrypt_enc_get_block_size(td);
        } else {
                return mcrypt_get_algo_iv_size(td);
        }
}

WIN32DLL_DEFINE
int mcrypt_enc_get_key_size(MCRYPT td)
{
        const char* error;
        int (*_mcrypt_get_key_size) (void);

        _mcrypt_get_key_size = mcrypt_dlsym(td->algorithm_handle, "_mcrypt_get_key_size");
        if (_mcrypt_get_key_size == NULL) {
                error = lt_dlerror();
                if (error!=NULL) {
                        fputs(error, stderr);
                        fputs("\n", stderr);
                }
                return MCRYPT_UNKNOWN_ERROR;
        }
        return _mcrypt_get_key_size();
}

WIN32DLL_DEFINE
int *mcrypt_enc_get_supported_key_sizes(MCRYPT td, int *len)
{
        int *(*_mcrypt_get_key_sizes) (int *);
        int *size, *ret;
        const char* error;

        _mcrypt_get_key_sizes =
            mcrypt_dlsym(td->algorithm_handle, "_mcrypt_get_supported_key_sizes");
        if (_mcrypt_get_key_sizes == NULL) {
                error = lt_dlerror();
                if (error!=NULL) {
                        fputs(error, stderr);
                        fputs("\n", stderr);
                }
                *len = 0;
                return NULL;
        }

        size = _mcrypt_get_key_sizes(len);
        
        ret = NULL;
        if (size!=NULL && (*len) != 0) {
                ret = malloc( sizeof(int)*(*len));
                if (ret==NULL) return NULL;
                memcpy( ret, size, sizeof(int)*(*len));
        }
        return ret;
}

WIN32DLL_DEFINE
int mcrypt_enc_is_block_algorithm(MCRYPT td)
{
        int (*_is_block_algorithm) (void);
        const char* error;

        _is_block_algorithm = mcrypt_dlsym(td->algorithm_handle, "_is_block_algorithm");
        if (_is_block_algorithm == NULL) {
                error = lt_dlerror();
                if (error!=NULL) {
                        fputs(error, stderr);
                        fputs("\n", stderr);
                }
                return MCRYPT_UNKNOWN_ERROR;
        }

        return _is_block_algorithm();
}

WIN32DLL_DEFINE
char *mcrypt_enc_get_algorithms_name(MCRYPT td)
{
        const char *(*_mcrypt_get_algorithms_name) (void);
        const char* error;

        _mcrypt_get_algorithms_name =
            mcrypt_dlsym(td->algorithm_handle, "_mcrypt_get_algorithms_name");
        if (_mcrypt_get_algorithms_name == NULL) {
                error = lt_dlerror();
                if (error!=NULL) {
                        fputs(error, stderr);
                        fputs("\n", stderr);
                }
                return NULL;
        }

        return strdup(_mcrypt_get_algorithms_name());
}

WIN32DLL_DEFINE
int init_mcrypt(MCRYPT td, void *buf, const void *key, int keysize, const void *iv)
{
        int (*_init_mcrypt) (void *, const void *, int, const void *, int);
        const char* error;

        _init_mcrypt = mcrypt_dlsym(td->mode_handle, "_init_mcrypt");
        if (_init_mcrypt == NULL) {
                error = lt_dlerror();
                if (error!=NULL) {
                        fputs(error, stderr);
                        fputs("\n", stderr);
                }
                return MCRYPT_UNKNOWN_ERROR;
        }

        return _init_mcrypt(buf, key, keysize, iv, mcrypt_enc_get_block_size(td));
}

WIN32DLL_DEFINE
int end_mcrypt(MCRYPT td, void *buf)
{
        int (*_end_mcrypt) (void *);
        const char* error;

        _end_mcrypt = mcrypt_dlsym(td->mode_handle, "_end_mcrypt");
        if (_end_mcrypt == NULL) {
                error = lt_dlerror();
                if (error!=NULL) {
                        fputs(error, stderr);
                        fputs("\n", stderr);
                }
                return MCRYPT_UNKNOWN_ERROR;
        }

        return _end_mcrypt(buf);
}

WIN32DLL_DEFINE
int mcrypt(MCRYPT td, void *buf, void *a, int b)
{
        int (*_mcrypt) (void *, void *, int, int, void *, void *, void*);
        _mcrypt = td->m_encrypt;

        return _mcrypt(buf, a, b, mcrypt_enc_get_block_size(td), td->akey,
                       td->a_encrypt, td->a_decrypt);
}

WIN32DLL_DEFINE
int mdecrypt(MCRYPT td, void *buf, void *a, int b)
{
        int (*_mdecrypt) (void *, void *, int, int, void *, void *, void*);

        _mdecrypt = td->m_decrypt;
        return _mdecrypt(buf, a, b, mcrypt_enc_get_block_size(td),
                         td->akey, td->a_encrypt, td->a_decrypt);
}

WIN32DLL_DEFINE
char *mcrypt_enc_get_modes_name(MCRYPT td)
{
        const char *(*_mcrypt_get_modes_name) (void);
        const char* error;

        _mcrypt_get_modes_name = mcrypt_dlsym(td->mode_handle, "_mcrypt_get_modes_name");
        if (_mcrypt_get_modes_name == NULL) {
                error = lt_dlerror();
                if (error!=NULL) {
                        fputs(error, stderr);
                        fputs("\n", stderr);
                }
                return NULL;
        }

        return strdup(_mcrypt_get_modes_name());
}

WIN32DLL_DEFINE
int mcrypt_enc_is_block_mode(MCRYPT td)
{
        int (*_is_block_mode) (void);
        const char* error;
        
        _is_block_mode = mcrypt_dlsym(td->mode_handle, "_is_block_mode");
        if (_is_block_mode == NULL) {
                error = lt_dlerror();
                if (error!=NULL) {
                        fputs(error, stderr);
                        fputs("\n", stderr);
                }
                return MCRYPT_UNKNOWN_ERROR;
        }

        return _is_block_mode();
}

WIN32DLL_DEFINE
int mcrypt_enc_mode_has_iv(MCRYPT td)
{
        int (*_has_iv) (void);
        const char* error;

        _has_iv = mcrypt_dlsym(td->mode_handle, "_has_iv");
        if (_has_iv == NULL) {
                error = lt_dlerror();
                if (error!=NULL) {
                        fputs(error, stderr);
                        fputs("\n", stderr);
                }
                return MCRYPT_UNKNOWN_ERROR;
        }

        return _has_iv();
}

WIN32DLL_DEFINE
int mcrypt_enc_is_block_algorithm_mode(MCRYPT td)
{
        int (*_is_a_block_mode) (void);
        const char* error;

        _is_a_block_mode = mcrypt_dlsym(td->mode_handle, "_is_block_algorithm_mode");
        if (_is_a_block_mode == NULL) {
                error = lt_dlerror();
                if (error!=NULL) {
                        fputs(error, stderr);
                        fputs("\n", stderr);
                }
                return MCRYPT_UNKNOWN_ERROR;
        }

        return _is_a_block_mode();
}

WIN32DLL_DEFINE
int mcrypt_enc_self_test(MCRYPT td)
{
        int (*_self_test) (void);
        const char* error;

        _self_test = mcrypt_dlsym(td->algorithm_handle, "_mcrypt_self_test");
        if (_self_test == NULL) {
                error = lt_dlerror();
                if (error!=NULL) {
                        fputs(error, stderr);
                        fputs("\n", stderr);
                }
                return MCRYPT_UNKNOWN_ERROR;
        }

        return _self_test();
}

WIN32DLL_DEFINE
int mcrypt_module_self_test(const char *algorithm, const char *a_directory)
{
        int i;
        void* rr;
        mcrypt_dlhandle _handle;
        int (*_self_test) (void);
        const char* error;

        if (lt_dlinit() != 0) {
                return MCRYPT_UNKNOWN_ERROR;
        }

        rr = mcrypt_dlopen(&_handle, a_directory, NULL, algorithm);

        if (!rr) {
                error=lt_dlerror();
                if (error!=NULL) {
                        fputs( error, stderr);
                        fputs("\n", stderr);
                }
                lt_dlexit();
                return MCRYPT_UNKNOWN_ERROR;
        }

        _self_test = mcrypt_dlsym(_handle, "_mcrypt_self_test");
        if (_self_test == NULL) {
                mcrypt_dlclose(_handle);
                lt_dlexit();
                return MCRYPT_UNKNOWN_ERROR;
        }
        
        i = _self_test();

        mcrypt_dlclose(_handle);
        if (lt_dlexit() != 0) {
                return MCRYPT_UNKNOWN_ERROR;
        }

        return i;
}

WIN32DLL_DEFINE
int mcrypt_module_algorithm_version(const char *algorithm, const char *a_directory)
{
        int i;
        mcrypt_dlhandle _handle;
        int (*_version) (void);
        const char* error;
        void* rr;
        
        if (lt_dlinit() != 0) {
                return MCRYPT_UNKNOWN_ERROR;
        }

        rr = mcrypt_dlopen(&_handle, a_directory, NULL, algorithm);
        if (!rr) {
                error=lt_dlerror();
                if (error!=NULL) {
                        fputs( error, stderr);
                        fputs("\n", stderr);
                }
                lt_dlexit();
                return MCRYPT_UNKNOWN_ERROR;
        }

        _version = mcrypt_dlsym(_handle, "_mcrypt_algorithm_version");
        if (_version==NULL) {
                mcrypt_dlclose(_handle);
                lt_dlexit();
                return MCRYPT_UNKNOWN_ERROR;
        }

        i = _version();

        mcrypt_dlclose(_handle);
        if (lt_dlexit() != 0) {
                return MCRYPT_UNKNOWN_ERROR;
        }

        return i;
}

WIN32DLL_DEFINE
int mcrypt_module_mode_version(const char *mode, const char *m_directory)
{
        int i;
        mcrypt_dlhandle _handle;
        int (*_version) (void);
        const char* error;
        void * rr;

        if (lt_dlinit() != 0) {
                return MCRYPT_UNKNOWN_ERROR;
        }

        rr = mcrypt_dlopen( &_handle, m_directory, NULL, mode);
        if (!rr) {
                error=lt_dlerror();
                if(error!=NULL) {
                        fputs(error, stderr);
                        fputs("\n", stderr);
                }
                lt_dlexit();
                return MCRYPT_UNKNOWN_ERROR;
        }

        _version = mcrypt_dlsym( _handle, "_mcrypt_mode_version");
        if (_version==NULL) {
                mcrypt_dlclose(_handle);
                lt_dlexit();
                return MCRYPT_UNKNOWN_ERROR;
        }

        i = _version();

        mcrypt_dlclose(_handle);
        if (lt_dlexit() != 0) {
                return MCRYPT_UNKNOWN_ERROR;
        }

        return i;
}

WIN32DLL_DEFINE
int mcrypt_module_is_block_algorithm(const char *algorithm, const char *a_directory)
{
        int i;
        mcrypt_dlhandle _handle;
        int (*_is_block_algorithm) (void);
        const char* error;
        void * rr;
        
        if (lt_dlinit() != 0) {
                return MCRYPT_UNKNOWN_ERROR;
        }

        rr = mcrypt_dlopen( &_handle, a_directory, NULL, algorithm);
        if (!rr) {
                error=lt_dlerror();
                if(error!=NULL) {
                        fputs( error, stderr);
                        fputs("\n", stderr);
                }
                lt_dlexit();
                return MCRYPT_UNKNOWN_ERROR;
        }

        _is_block_algorithm = mcrypt_dlsym(_handle, "_is_block_algorithm");
        if (_is_block_algorithm==NULL) {
                mcrypt_dlclose(_handle);
                lt_dlexit();
                return MCRYPT_UNKNOWN_ERROR;
        }

        i = _is_block_algorithm();

        mcrypt_dlclose(_handle);
        if (lt_dlexit() != 0) {
                return MCRYPT_UNKNOWN_ERROR;
        }

        return i;
}

WIN32DLL_DEFINE
int mcrypt_module_is_block_algorithm_mode(const char *mode, const char *m_directory)
{
        int i;
        mcrypt_dlhandle _handle;
        int (*_is_a_block_mode) (void);
        const char* error;
        void * rr;

        if (lt_dlinit() != 0) {
                return MCRYPT_UNKNOWN_ERROR;
        }

        rr = mcrypt_dlopen( &_handle, m_directory, NULL, mode);
        if (!rr) {
                error=lt_dlerror();
                if(error!=NULL) {
                        fputs( error, stderr);
                        fputs("\n", stderr);
                }
                lt_dlexit();
                return MCRYPT_UNKNOWN_ERROR;
        }

        _is_a_block_mode = mcrypt_dlsym(_handle, "_is_block_algorithm_mode");
        if (_is_a_block_mode==NULL) {
                mcrypt_dlclose(_handle);
                lt_dlexit();
                return MCRYPT_UNKNOWN_ERROR;
        }

        i = _is_a_block_mode();

        mcrypt_dlclose(_handle);
        if (lt_dlexit() != 0) {
                return MCRYPT_UNKNOWN_ERROR;
        }

        return i;
}

WIN32DLL_DEFINE
int mcrypt_module_is_block_mode(const char *mode, const char *m_directory)
{
        void * rr;
        int i;
        mcrypt_dlhandle _handle;
        int (*_is_block_mode) (void);
        const char* error;

        if (lt_dlinit() != 0) {
                return MCRYPT_UNKNOWN_ERROR;
        }

        rr = mcrypt_dlopen( &_handle, m_directory, NULL, mode);
        if (!rr) {
                error=lt_dlerror();
                if(error!=NULL) {
                        fputs( error, stderr);
                        fputs("\n", stderr);
                }
                lt_dlexit();
                return MCRYPT_UNKNOWN_ERROR;
        }

        _is_block_mode = mcrypt_dlsym(_handle, "_is_block_mode");
        if (_is_block_mode==NULL) {
                mcrypt_dlclose(_handle);
                lt_dlexit();
                return MCRYPT_UNKNOWN_ERROR;
        }

        i = _is_block_mode();

        mcrypt_dlclose(_handle);
        if (lt_dlexit() != 0) {
                return MCRYPT_UNKNOWN_ERROR;
        }

        return i;
}

WIN32DLL_DEFINE
int mcrypt_module_get_algo_block_size(const char *algorithm, const char *a_directory)
{
        int i;
        mcrypt_dlhandle _handle;
        int (*_get_block_size) (void);
        const char* error;
        void * rr;

        if (lt_dlinit() != 0) {
                return MCRYPT_UNKNOWN_ERROR;
        }

        rr = mcrypt_dlopen( &_handle, a_directory, NULL, algorithm);
        if (!rr) {
                error=lt_dlerror();
                if(error!=NULL) {
                        fputs( error, stderr);
                        fputs("\n", stderr);
                }
                lt_dlexit();
                return MCRYPT_UNKNOWN_ERROR;
        }

        _get_block_size = mcrypt_dlsym(_handle, "_mcrypt_get_block_size");
        if (_get_block_size==NULL) {
                mcrypt_dlclose(_handle);
                lt_dlexit();
                return MCRYPT_UNKNOWN_ERROR;
        }

        i = _get_block_size();

        mcrypt_dlclose(_handle);
        if (lt_dlexit() != 0) {
                return MCRYPT_UNKNOWN_ERROR;
        }

        return i;
}

WIN32DLL_DEFINE
int mcrypt_module_get_algo_key_size(const char *algorithm, const char *a_directory)
{
        int i;
        mcrypt_dlhandle _handle;
        int (*_get_key_size) (void);
        const char* error;
        void * rr;

        if (lt_dlinit() != 0) {
                return MCRYPT_UNKNOWN_ERROR;
        }

        rr = mcrypt_dlopen( &_handle, a_directory, NULL, algorithm);
        if (!rr) {
                error=lt_dlerror();
                if(error!=NULL) {
                        fputs( error, stderr);
                        fputs("\n", stderr);
                }
                lt_dlexit();
                return MCRYPT_UNKNOWN_ERROR;
        }

        _get_key_size = mcrypt_dlsym(_handle, "_mcrypt_get_key_size");
        if (_get_key_size==NULL) {
                mcrypt_dlclose(_handle);
                lt_dlexit();
                return MCRYPT_UNKNOWN_ERROR;
        }

        i = _get_key_size();

        mcrypt_dlclose(_handle);
        if (lt_dlexit() != 0) {
                return MCRYPT_UNKNOWN_ERROR;
        }

        return i;
}

WIN32DLL_DEFINE
int *mcrypt_module_get_algo_supported_key_sizes(const char *algorithm,
                                                const char *a_directory,
                                                int *len)
{
        mcrypt_dlhandle _handle;
        int *(*_mcrypt_get_key_sizes) (int *);
        int *size;
        int * ret_size;
        const char* error;
        void * rr;

        
        if (lt_dlinit() != 0) {
                *len = 0;
                return NULL;
        }

        rr = mcrypt_dlopen( &_handle, a_directory, NULL, algorithm);
        if (!rr) {
                error=lt_dlerror();
                if(error!=NULL) {
                        fputs( error, stderr);
                        fputs("\n", stderr);
                }
                lt_dlexit();
                *len = 0;
                return NULL;
        }

        _mcrypt_get_key_sizes =
            mcrypt_dlsym(_handle, "_mcrypt_get_supported_key_sizes");
        if (_mcrypt_get_key_sizes==NULL) {
                mcrypt_dlclose(_handle);
                lt_dlexit();
                *len = 0;
                return NULL;
        }

        ret_size = NULL;
        size = _mcrypt_get_key_sizes(len);
        if (*len!=0 && size!=NULL) {
                ret_size = malloc( (*len)*sizeof(int));
                if (ret_size!=NULL) {
                        memcpy( ret_size, size, (*len)*sizeof(int));
                }
        } else *len = 0;
        
        mcrypt_dlclose(_handle);
        if (lt_dlexit() != 0) {
                return NULL;
        }

        return ret_size;
}