sign & verify test ...
signing text 'some text to sign' using private key rsa_M1MIPS7478.key
signature is 'brpTWbhntX5D6uHjUUKATjRbcwzANpnims4cJyYSVXFsJhgyQwmNl4txT1jbLup51yJjt2SKO0H7ioN1MjSrUKhCU9Gxv9EYRXYFfAV+EeEP9i8w8HbUoeWD8ZZc0OA3yeoDzRK9AwgDGOXXM+V3Z70aAbk967m7AfLFJjplJjcBR/w1KRrW8FnExYCtavf8lZM4+/cHOPYBIo3ONhT6fyyiZo7V3cV3Uf26lolEPWXuKCdoaLkfnEe143cbng7afx+3HpFdRchzC5FSrYK7o2uO4fXGDzNP2D8mBdtqfGfWwklBVZZDD/fnlv7SCqXwGg2NS4dNZVAkjH41+GnpwQ=='
verifying signature using public key rsa_M1MIPS7478.pub
verify result: ok