Encrypting keypad module
View Patent ↗An encrypting keypad module ( 30 ) comprising a keypad ( 40 ) and an encryption unit ( 42 ) is described. The encryption unit ( 42 ) includes an interpreter ( 56 ) for receiving a file ( 150 ) containing data and instructions for processing the data. The encryption unit ( 42 ) is operable to process the data in the file ( 150 ) by interpreting the instructions in the file ( 150 ). This enables a file ( 150 ) to be used to instruct the encryption unit ( 42 ) about the data that is to be operated on and the type of operations to be performed on the data.
1. A method of deriving a new encryption key for use in an encrypting keypad module, the method comprising:
receiving a file containing (i) input data, (ii) a first command indicating an algorithm, (iii) a second command indicating an encryption key which is already stored at the encrypting keypad module, and (iv) instructions for making a new encryption key;
using the indicated algorithm and the indicated encryption key to decrypt the input data; and
executing the instructions to direct how the decrypted input data is to be operated on to produce a new encryption key which is different from the encryption key which is already stored at the encrypting keypad module.
2. A method according to claim 1 , further comprising:
storing the new encryption key in the encrypting keypad module.
3. A method according to claim 1 , wherein the file has a structure comprising tagged commands and data.
4. A method of operating an encrypting keypad module having a first encryption key which is already stored at the encrypting keypad module, the method comprising:
receiving a file containing (i) input data, (ii) a command indicating an algorithm, and (iii) instructions for making a new encryption key which is different from the first encryption key;
using the indicated algorithm and the first encryption key to decrypt the input data;
executing the instructions to direct how the decrypted input data is to be operated on to produce a second encryption key which is different from the first encryption key which is already stored at the encrypting keypad module; and
storing the second encryption key in the encrypting keypad module.
5. A method according to claim 4 , wherein the file has a structure comprising tagged commands and data.