Abstract: A processor is configured to assess the state of a first component of a computing system, and then control whether a second component can access a third component based on the state of the first component to, e.g., mitigate malicious attacks that would exploit changes to the third component. In one example, the computing system includes multiple central processing units (CPUs), at least one of which is equipped to operate in a secure mode for executing secure code that may access sensitive information such as cryptographic keys. In the example, non-secure code is blocked and/or delayed from accessing clock or voltage control registers when any of the CPUs of the system is running secure code. This prevents non-secure code from causing transient faults when secure code is running In some examples, the registers are locked using a global secure-side lock. The lockable registers are referred to herein as grey-list registers.

Abstract: Embodiments of an invention for using dark bits to reduce physically unclonable function (PUF) error rates are disclosed. In one embodiment, an integrated circuit includes a PUF cell array and dark bit logic. The PUF cell array is to provide a raw PUF value. The dark bit logic is to select PUF cells to mark as dark bits and to generate a dark bit mask based on repeated testing of the PUF cell array.

Abstract: Embodiments of an invention for using dark bits to reduce physically unclonable function (PUF) error rates are disclosed. In one embodiment, an integrated circuit includes a PUF cell array and dark bit logic. The PUF cell array is to provide a raw PUF value. The dark bit logic is to select PUF cells to mark as dark bits and to generate a dark bit mask based on repeated testing of the PUF cell array.

Abstract: A cryptographic circuit with voltage island-based tamper detection and response is disclosed. The circuit includes a voltage island having at least one monitoring circuit and a first storage area for security parameters. The circuit also includes a second storage area for key storage and management logic to tamper the security parameters upon detection of an environmental failure.

Abstract: A physically secure processing assembly is provided that includes dies mounted on a substrate so as to sandwich the electrical contacts of the dies between the dies and the substrate. The substrate is provided with substrate contacts and conductive pathways that are electrically coupled to the die contacts and extend through the substrate. Electrical conductors surround the conductive pathways. A monitoring circuit detects a break in continuity of one or more of the electrical conductors, and preferably renders the assembly inoperable. Preferably, an epoxy encapsulation is provided to prevent probing tools from being able to reach the die or substrate contacts.

Abstract: A method for embedding tamper proof layers and discrete components into a printed circuit board stack-up is disclosed. According to this method, a plating mask is applied on a base substrate to cover partially one of its faces. Conductive ink is then spread on this face so as to fill the gap formed by the plating mask. To obtain a uniform distribution of the conductive ink and then gel it, the conductive ink is preferably heated. A dielectric layer is applied on the conductive ink layer and the polymerization process is ended to obtain a strong adhesion between these two layers. In a preferred embodiment, conductive tracks are simultaneously designed on the other face of the base substrate to reduce thermo-mechanical strains and deformations.