#ifndef __X509_SERIAL_H
#define __X509_SERIAL_H
class X509_sn
{
public:
	static BIGNUM * Load_Serial ( const char * serialfile, bool create, ASN1_INTEGER ** retai );
	static int Save_Serial ( const char * serialfile, const char * suffix, BIGNUM * bn, ASN1_INTEGER ** retai );
};
//從序列文件中讀取序列號
inline
BIGNUM * X509_sn::Load_Serial ( const char * serialfile,
							   bool create,
							   ASN1_INTEGER ** retai )
{
	BIGNUM * bnret = 0;
	BIO    * bin   = 0;
	ASN1_INTEGER * ai = 0;
	char buf[BUFSIZZ] = {0};

	if ( serialfile == 0 ) goto end;
	if ( ( ai = ASN1_INTEGER_new () ) == NULL ) goto end;
	if ( ( bin = BIO_new ( BIO_s_file () ) ) == NULL ) goto end;
	if ( BIO_read_filename ( bin, serialfile ) <= 0 )
	{
		if ( create )
		{
			//新建
			ASN1_INTEGER_set ( ai, 1 );
			bnret = BN_new ( );
			if ( bnret )
				BN_one ( bnret );
		}
	}
	else
	{
		//讀取
		if ( !a2i_ASN1_INTEGER ( bin, ai, buf, BUFSIZZ ) )
		{
			CError::Interface()->Handle_Error ( 0, "讀取序列號失敗:%s", serialfile );
			goto end;
		}
		//轉換
		if ( ( bnret = ASN1_INTEGER_to_BN ( ai, NULL) ) == NULL )
		{
			CError::Interface()->Handle_Error ( 0, "數據轉換失敗(BIN->BIGNUM)" );
			goto end;
		}
	}
	if ( bnret && retai )
	{
		*retai = ai;
		ai = NULL;
	}
end:
	if ( bin ) BIO_free ( bin );
	if ( ai ) ASN1_INTEGER_free ( ai );
	return bnret;
}
//保存序列號到序列號文件
inline 
int X509_sn::Save_Serial ( const char * serialfile,
						  const char * suffix,
						  BIGNUM * bnsn, ASN1_INTEGER ** retai )
{
	BIO * bout = 0;
	ASN1_INTEGER * ai = 0;
	char buf[BUFSIZZ] = {0};
	int ret = -1, filelen;

	if ( serialfile == 0 ) return ret;
	//判斷文件長度
	filelen = strlen ( serialfile );
	if ( suffix )
		filelen += strlen ( suffix );
	if ( filelen > BUFSIZZ )
	{
		CError::Interface()->Handle_Error ( 0, "序列號文件過長:%s", serialfile );
		goto end;
	}
	//增加后綴
	BUF_strlcpy ( buf, serialfile, BUFSIZZ );
	if ( suffix )
		BIO_snprintf ( buf, sizeof buf, "%s.%s", serialfile, suffix );

	//生成IO
	if ( ! ( bout = BIO_new ( BIO_s_file () ) ) == NULL ) goto end;
	if ( BIO_write_filename ( bout, buf ) <= 0 )
	{
		CError::Interface()->Handle_Error ( 0, "寫文件失敗:%s", buf );
		goto end;
	}
	if ( (ai = BN_to_ASN1_INTEGER ( bnsn, NULL ) ) == NULL )
	{
		CError::Interface()->Handle_Error ( 0, "轉換格式失敗(序列號->ASN.1)" );
		goto end;
	}
	i2a_ASN1_INTEGER ( bout, ai );
	if ( retai )
	{
		*retai = ai;
		ai = 0;
	}
	ret = 0;
end:
	if ( bout ) BIO_free ( bout );
	if ( ai ) ASN1_INTEGER_free ( ai );
	return ret;
}
#endif