/**********************************************************************
 *                        gost_ctl.c                                  *
 *             Copyright (c) 2005-2006 Cryptocom LTD                  *
 *       This file is distributed under the same license as OpenSSL   *
 *                                                                    *
 *        Implementation of control commands for GOST engine          *
 *            OpenSSL 0.9.9 libraries required                        *
 **********************************************************************/            
#include <stdlib.h>
#include <string.h>
#include <openssl/crypto.h>
#include <openssl/err.h>
#include <openssl/engine.h>
#include <openssl/buffer.h>
#include "gost_lcl.h"

static char *gost_params[GOST_PARAM_MAX+1]={NULL};
static const char *gost_envnames[]={"CRYPT_PARAMS"};
const ENGINE_CMD_DEFN gost_cmds[]=
	{
/*	{ GOST_CTRL_RNG,
	"RNG",
	"Type of random number generator to use",
	ENGINE_CMD_FLAG_STRING
	},
	{ GOST_CTRL_RNG_PARAMS,
	"RNG_PARAMS",
	"Parameter for random number generator",
	ENGINE_CMD_FLAG_STRING
	},
*/	  { GOST_CTRL_CRYPT_PARAMS,
		"CRYPT_PARAMS",
		"OID of default GOST 28147-89 parameters",
		ENGINE_CMD_FLAG_STRING
			},
{0,NULL,NULL,0}
	};

void gost_param_free() 
{
	int i;
	for (i=0;i<=GOST_PARAM_MAX;i++) 
		if (gost_params[i]!=NULL) 
			{
			OPENSSL_free(gost_params[i]);
			gost_params[i]=NULL;
			}
		
}

int gost_control_func(ENGINE *e,int cmd,long i, void *p, void (*f)(void))
	{
	int param = cmd-ENGINE_CMD_BASE;
	int ret=0;
	if (param <0 || param >GOST_PARAM_MAX) return -1;
	ret=gost_set_default_param(param,p);
	return ret;
	}

const char *get_gost_engine_param(int param) 
	{
	char *tmp;
	if (param <0 || param >GOST_PARAM_MAX) return NULL;
	if (gost_params[param]!=NULL) 
		{
		return gost_params[param];
		}
	tmp = getenv(gost_envnames[param]);
	if (tmp) 
		{
		if (gost_params[param]) OPENSSL_free(gost_params[param]);
		gost_params[param] = BUF_strdup(tmp);
		return gost_params[param];
		}	
	return NULL;
	}	

int gost_set_default_param(int param, const char *value) 
	{
	const char *tmp;
	if (param <0 || param >GOST_PARAM_MAX) return 0;
	tmp = getenv(gost_envnames[param]);
	/* if there is value in the environment, use it, else -passed string * */
	if (!tmp) tmp=value;
	if (gost_params[param]) OPENSSL_free(gost_params[param]);
	gost_params[param] = BUF_strdup(tmp);

	return 1;
	}