Secure removable card having a plurality of integrated circuit dies
A secure removable card has electrical connections for communication therewith. The card comprises a first integrated circuit die, with the first die including a processor. The card has a second integrated circuit die, with the second die including a non-volatile memory for storing a secret key, and a controller for controlling the operation of the non-volatile memory. A bus connects the first die with the second die. The processor can generate a key pair, having a public key portion and a private key portion upon power up, and transfers the public key portion across the bus to the second die. The controller can receive the public key and encrypt the secret key with the public key to generate a first encrypted key, and can transfer the first encrypted key across the bus to the first die. The processor can receive the first encrypted key and can decrypt the first encrypted key to recover the secret key, and can encrypt data with the secret key for communicating along the electrical connections external to the card.
1. A secure removable card having electrical connections for communication therewith, comprising:
a first integrated circuit die, said first die including a processor;
a second integrated circuit die, said second die including a non-volatile memory for storing a secret key, and a controller for controlling the operation of the non-volatile memory;
a bus connecting the first die with the second die;
wherein the processor for generating a key pair, having a public key portion and a private key portion upon power up, with said key pair generated not based upon stored data, and for transferring the public key portion across the bus to the second die;
wherein the controller for receiving the public key and for encrypting the secret key with the public key to generate a first encrypted key, and for transferring the first encrypted key across the bus to the first die; and
wherein the processor for receiving the first encrypted key and for decrypting the first encrypted key to recover the secret key; and for encrypting data with said secret key for communicating along the electrical connections external to the card.
2. The card of claim 1 wherein said first die further includes a volatile memory embedded with said processor;
wherein said volatile memory for storing the secret key.
3. The card of claim 2 wherein said first die further comprising a random number generator, wherein the random number generator generate the public key portion and the private key portion.
4. The card of claim 1 wherein said processor decrypts the first encrypted key using the private key portion.
5. A method of securely communicating with a removable card, said card having electrical connections thereto, and having a first semiconductor die, a second semiconductor die with an electrical bus connecting the first die with the second die, packaged together, said first die having a processor, said second die having a non-volatile memory for storing a secret key, and a controller for controlling the operation of the non-volatile memory, said method comprising:
generating a key pair, upon power up of the processor, having a public key and a private key by the processor, wherein said key pair generated is not based upon stored data;
transferring the public key to the second die via the electrical bus;
encrypting the secret key using the public key by the controller to produce an encrypted key;
transferring the encrypted key to the first die via the electrical bus;
decrypting the encrypted key to extract the secret key by the processor; and
using the secret key to encrypt data to communicate on the electrical connections external to the card.
6. The method of claim 5 wherein said key pair is generated by a random number generator.
7. The method of claim 6 wherein said secret key is stored in a volatile memory embedded in the processor.
8. The method of claim 5 wherein said key pair is generated upon power up.
9. The method of claim 5 wherein said encrypted key is decrypted by using the secret key.