Integrated circuit configured to carry out symmetric encryption operations without secret key transmission

A method for decrypting encrypted binary data in a secure hardware environment, comprising:

• receiving a key number;
• generating a secret key from the key number and a unique key;
• generating a signature associated with the key number;
• receiving said encrypted binary data;
• receiving an authentication signature;
• decrypting said encrypted binary data by using said secret key if the signature generated is identical to the authentication signature;
• delivering decrypted binary data outside the secure hardware environment.

A method for encrypting binary data in a secure hardware environment, comprising:

• receiving a key number;
• generating a secret key from the key number and a unique key;
• non-reversibly generating a signature associated with the key number;
• receiving said binary data;
• encrypting said binary data by using the secret key;
• delivering outside the secure hardware environment encrypted binary data;
• and
• delivering the signature associated with the key number outside the secure hardware environment, said signature being adapted for being used as an authentication signature in a decryption method.