Nuvoton Technology Corporation

Dan Morav

Ziv Hershman

Moshe Alon

Oren Tanami

Ilan Margalit

Nir Tasher

Einat Luko

Nimrod Peled

Avraham Fishman

Eyal Cohen

Yossef Talmi

Yossi Talmi

Uri Trichter

A device including a network interface, a memory and a processor. The network interface is configured to communicate with a verifier over a communication network. The memory is configured to store multiple layers of mutable code, the layers identifiable by respective measurements. The processor is configured to generate, for a given boot cycle, a nonce associated uniquely with the given boot cycle, to receive a challenge from the verifier for attestation of a given layer of the mutable code, to calculate an attestation key based on (i) a Unique Device Secret (UDS) stored securely in the device, (ii) a measurement of the given layer taken by another layer, and (iii) the nonce generated for the given boot cycle, to calculate a response for the challenge, by signing the challenge using the attestation key, and to send the response to the verifier for verification of the given layer.

Device attestation including attestation-key modification following boot event

A method for provisioning an electronic device includes providing a semiconductor wafer on which multiple integrated circuit (IC) chips have been fabricated. Each chip includes a secure memory and programmable logic, which is configured to store at least two keys in the secure memory and to compute digital signatures over data using the at least two keys. A respective first key is provisioned into the secure memory of each of the chips via electrical probes applied to contact pads on the semiconductor wafer. After dicing of the wafer, a respective second key is provisioned into the secure memory of each of the chips via contact pins of the chips. A respective provisioning report is received from each of the chips with a digital signature computed by the logic using both of the respective first and second keys. The provisioning is verified based on the digital signature.

Multi-stage provisioning of secret data

A computer system includes one or more memory devices, non-resettable memory elements and a processor. The first memory device is configured to store in the one or more memory devices (i) a first version of a multi-stage bootstrap program for bootstrapping the computer system, the bootstrap program including a self-test program that tests the bootstrap program, and (ii) a second version of the bootstrap program known to be trustworthy. The non-resettable memory elements are configured to store non-resettable indicators including at least a self-test-request indicator and a self-test-passed indicator. The processor is configured to retrieve the first version of the bootstrap program, and, if the first version is at least as recent as the trustworthy second version, to bootstrap the computer system securely using the first version and the non-resettable indicators.

Secure firmware management with hierarchical boot sequence using last known good firmware

An Integrated Circuit (IC) includes functional circuitry and protection circuitry. The protection circuitry is configured to maintain a counter value, which is indicative of a cumulative amount of hostile attacking attempted on the functional circuitry over a lifetime of the IC, to detect events indicative of suspected hostile attacks on the functional circuitry, to decide, responsively to a detected event, on an update of the counter value depending on a time difference between the detected event and a most recent power-up in the IC, and update the counter value in accordance with the decided update, and to disable at least part of the IC in response to the counter value crossing a threshold.

Secure IC with soft security countermeasures

A method for initializing a computer system, which includes a Central Processing Unit (CPU), a Trusted Root Device and a Trusted Platform Module (TPM), includes authenticating a boot code of the CPU using the Trusted Root Device, and booting the CPU using the authenticated boot code. A challenge-response transaction, in which the TPM authenticates the Trusted Root Device, is initiated by the CPU following booting of the CPU. Only in response to successful authentication of the Trusted Root Device using the challenge-response transaction, a resource used in operating the computer system is released from the TPM.

Binding of TPM and root device

A controller includes a host interface and a processor. The host interface is configured for communicating with a host. The processor is configured to receive from the host, via the host interface, instructions for execution in a Non-Volatile Memory (NVM), to identify among the instructions an instruction, which pertains to a secure monotonic counter and is intended for execution in an NVM having a secure monotonic counter embedded therein, and to execute the identified instruction, and respond to the host responsively to the instruction, instead of the NVM.

RPMC flash emulation

A secured device includes an interface and a processor. The interface is configured to connect to a bus, to which a host and a second device are coupled. At least the second device operates over the bus in a slave mode, and the host operates on the bus as a bus master that initiates transactions on the bus, at least on behalf of the secured device. The processor is configured to request the host to initiate, for the secured device, a transaction that accesses the second device over the bus, to monitor one or more signals on the bus, at least within a period during which the host accesses the second device over the bus in performing the requested transaction, and to identify, based on the monitored signals, whether a security violation occurred in performing the requested transaction.

Secured master-mediated transactions between slave devices using bus monitoring

A security device includes an interface and a processor. The interface is configured for connecting to a bus that serves a host device and a non-volatile memory (NVM) device. The processor is connected to the bus in addition to the host device and the NVM device. The processor is configured to detect on the bus a boot process, in which the host device retrieves boot code from the NVM device, and to ascertain a security of the boot process, based on an authentic copy of at least part of the boot code of the host device.

Secure system boot monitor

A system for improving utilization of a nonvolatile flash memory device which has pages whose guaranteed per-cycle erase time and guaranteed number of cycles are known, the system comprising erase time determination functionality for individual pages; de-facto total erase-time accumulation functionality incrementing, for each erase cycle to which an individual page is subjected, by the individual page's de facto erase time per cycle as provided by the erase time measurement functionality; and flash memory page usage monitoring functionality operative to control usage of pages in flash memory including selecting at least one individual flash memory page depending on a comparison between the individual flash memory page's de facto total erase time and a guaranteed erase time computed as a product of the guaranteed per-cycle erase time and of the guaranteed number of cycles.

System and methods for increasing useful lifetime of a flash memory device

A security device includes an interface and a processor. The interface is configured for connecting to a bus that serves one or more peripheral devices. The bus includes (i) one or more dedicated signals that are each dedicated to a respective one of the peripheral devices, and (ii) one or more shared signals that are shared among the peripheral devices served by the bus. The processor is connected to the bus as an additional device in addition to the peripheral devices, and is configured to disrupt on the bus a transaction in which a bus-master device attempts to access a given peripheral device, by disrupting a dedicated signal associated with the given peripheral device.

Secure access to peripheral devices over a bus

An apparatus includes a memory, an interface and read restriction logic. The read restriction logic is configured to receive via the interface a request to read a data value from a specified address of the memory, to retrieve the data value from the specified address, to check, upon finding that the specified address falls in an address range that is predefined as restricted, whether the retrieved data value belongs to a predefined set of permitted data values, to respond to the request with the retrieved data value when the retrieved data value belongs to the set of permitted data values, and, otherwise, when the retrieved data value does not belong to the set of permitted data values, to respond to the request with a dummy data value.

Secure memory access using memory read restriction

A method in a security device that provides a security service to a host includes receiving a security command from an application program running on the host. The security command is executed by accessing a Non-Volatile Memory (NVM) device external to the security device transparently to the application program via a dedicated device driver, which runs on the host and mediates between the NVM device and the security device.

Security device having indirect access to external non-volatile memory

An apparatus includes a Non-Volatile Memory (NVM) and a controller. The controller is configured to store in the NVM a state array, which includes multiple words. In each word, one or more bits are designated as lock-bits. The controller is further configured to set an operational state for the apparatus based on the lock-bits of the state array, by (i) deciding whether each word in the state array is locked or unlocked by comparing the lock-bits of that word to respective expected lock values, (ii) if all the words in the state array are found locked, setting the apparatus to a locked state, (iii) if all the words in the state array are found unlocked, setting the apparatus to an unlocked state, and (iv) if one or more of the words are found locked and one or more other words are found unlocked, setting the apparatus to an error state.

Secure integrated-circuit state management

An apparatus includes an interface and a processor. The interface is configured for communicating over a bus. The processor is configured to disrupt on the bus a transaction in which a bus-master device attempts to access a peripheral device without authorization, by forcing one or more dummy values on at least one line of the bus in parallel to at least a part of the transaction.

Methods and systems for Basic Input/Output System BIOS processing such as hashing are disclosed. In one embodiment, there is a direct interface between a security module and a non-volatile memory storing the BIOS in a computing system so that the security module may directly access the BIOS without using the central processing unit CPU as an intermediary. In one embodiment, the security module is powered by standby power and therefore can begin BIOS processing even if the computing system has not yet been turned on.

Growing community of inventors

Herzliya, Israel

Dan Morav