Method and system for securely updating firmware in a computing device

A computing device comprising:

• a data interface configured to receive a double-encrypted firmware image from an external firmware source, wherein the double-encrypted firmware image is generated from firmware that is encrypted a first time using a first crypto-key and then encrypted a second time using a second crypto-key, and to receive the second crypto-key from an external key source;
• a host processor configured to execute program code of the firmware;
• a non-volatile memory configured to store an encrypted image of the firmware;
• and
• a secure element located in a data path between the host processor and the non-volatile memory and having a crypto-engine, the crypto-engine being configured to decrypt the double-encrypted firmware image using the second crypto-key to produce an encrypted firmware image and the secure element being configured to provide the encrypted firmware image to the non-volatile memory of the computing device for storage;
• the host processor being configured to read the encrypted firmware image from the non-volatile memory, to decrypt the encrypted firmware image using the first crypto-key to produce the firmware, and to execute program code of the firmware on the computing device;
• wherein the secure element is configured to apply decryption to data addressed to code blocks in the non-volatile memory and to pass without decryption data addressed to data blocks in the non-volatile memory.

A method for confirming the presence of a secure element in a computing device, the computing device including a host processor and a non-volatile memory, the method comprising:

• receiving an encrypted random number at the secure element, wherein the random number is encrypted using a crypto-key;
• receiving the crypto-key from an external key source;
• decrypting the encrypted random number at the secure element using the crypto-key to produce a decrypted random number;
• storing the decrypted random number in the non-volatile memory of the computing device;
• reading the decrypted random number from the non-volatile memory of the computing device;
• comparing the decrypted random number to a stored version of the random number;
• and
• confirming the presence of the element if the decrypted random number matches the stored random number.