Nonvolatile memory device having authentication, and methods of operation and manufacture thereof
A memory device package encloses two separate die, one being a standard nonvolatile memory integrated circuit (“IC”) die, and the other being any suitable authentication IC die. Either die may be stacked upon the other, or the die may be placed side-by-side. The external contacts may correspond to the power and signal requirements of the standard nonvolatile memory IC die so that the pin-out of the memory device package may present a standard pinout. The power and signal requirements of the authentication IC die may be satisfied with some or all of the pins for the nonvolatile memory integrated circuit die, or with other unused pins of the device package. One or more additional external contacts may be added exclusively for the authentication integrated circuit die. One or more signals may be dedicated as between the standard nonvolatile memory IC die and the authentication IC die.
1. A method of authenticating a nonvolatile memory integrated circuit die contained in a package body having a plurality of contacts extending from or disposed on the package body, the nonvolatile memory integrated circuit die having a first interface electrically coupled to at least some of the contacts, comprising:
storing a root key in a nonvolatile memory array of an authentication integrated circuit die contained in the package body, the authentication integrated circuit die further comprising a second interface and an authentication engine coupled to the second interface, the nonvolatile memory array being coupled to the authentication engine and to the second interface;
maintaining a monotonic count within the nonvolatile memory array of the authentication integrated circuit die;
encrypting the monotonic count within the authentication engine to generate an encrypted count; and
furnishing the encrypted count from the authentication engine to one of the contacts via the second interface, the second interface being electrically coupled to at least some of the contacts.
2. The method of claim 1 wherein the authentication integrated circuit die comprises a volatile memory register coupled to the authentication engine, further comprising storing a session key in the volatile memory register of the authentication integrated circuit die, and wherein the encrypting step comprises encrypting the count with the session key.
3. A method of authenticating a nonvolatile memory integrated circuit die contained in a package body having a plurality of contacts extending from or disposed on the package body, the nonvolatile memory integrated circuit die having a first interface electrically coupled to at least some of the contacts, comprising:
storing a root key in a nonvolatile memory array of an authentication integrated circuit die contained in the package body, the authentication integrated circuit die further comprising a second interface, an authentication engine coupled to the second interface, and a volatile memory register coupled to the authentication engine, the nonvolatile memory array being coupled to the authentication engine and to the second interface;
maintaining a monotonic count within the nonvolatile memory array of the authentication integrated circuit die;
receiving, by the authentication integrated circuit die, a request associated with a keyed-HMAC for providing the monotonic count;
furnishing the monotonic count from the authentication engine to one of the contacts via the second interface, the second interface being electrically coupled to at least some of the contacts;
receiving, by the authentication integrated circuit die, a request associated with the keyed-HMAC for incrementing the monotonic count; and
incrementing the monotonic count in the authentication integrated circuit die.
4. The method of claim 3 further comprising:
computing a derived key based upon session data and the root key; and
storing the derived key in the volatile memory register;
wherein the keyed-HMAC is based upon the derived key.