Reliable Field Programmable Gate Arrays

Abstract

An approach to creating a tamper-resistant field programmable gate array (FPGA) and remotely reprogramming the tamper-resistant FPGA. In one aspect, determining whether a cryptographic key is stored in a physically unclonable function (PUF) of the FPGA. Further, in response to the cryptographic key not being stored in the PUF, writing the cryptographic key to a tamper-resistant memory associated with the back-end of line (BEOL) of the FPGA. In another aspect, writing a program key and a look-up table (LUT) to the tamper-resistant memory.

Description

[Technical Field]

[0001] The present invention relates generally to Field Programmable Gate Arrays (FPGAs), and more particularly to securing cryptographic circuits in FPGAs. [Background technology]

[0002] FPGAs consist of bit files stored in flash memory or on flash cards, typically downloaded over a network connection. Even if the bit files are typically encrypted, the encryption key used to secure the bit files can be discovered through side-channel attacks on the FPGA or techniques such as picosecond imaging circuit analysis (PICA) because the encryption key is stored in static random access memory (SRAM) or embedded flash. Once the encryption key is discovered, the bit files can be modified and / or reverse-engineered. The consequences of this security breach are equivalent to introducing unauthorized chips and code into the system. Summary of the Invention

[0003] According to one aspect of the present invention, a computer-implemented method for creating a tamper-resistant field programmable gate array (FPGA) is provided, the computer-implemented method including: determining, by one or more processors, whether a cryptographic key is stored in a physical unclonable function (PUF) of the FPGA; and, in response to the cryptographic key not being stored in the PUF, writing, by the one or more processors, the cryptographic key to tamper-resistant memory associated with a back end of the line (BEOL) of the FPGA; writing, by the one or more processors, a program key to the tamper-resistant memory; and writing, by the one or more processors, a look-up table (LUT) to the tamper-resistant memory.

[0004] According to another aspect of the present invention, a computer-implemented method for tamper-resistant remote reprogramming of a field programmable gate array (FPGA) is provided, the computer-implemented method including receiving, by one or more processors, a reprogramming request from a remote FPGA; generating, by the one or more processors, a random initialization vector; encrypting, by the one or more processors, a programming key and a bit file with an encryption key shared with the remote FPGA; and sending, by the one or more processors, the random initialization vector, the encrypted programming key, and the encrypted bit file to the FPGA.

[0005] According to another aspect of the present invention, there is provided a computer system for producing a tamper-resistant field programmable gate array (FPGA), the computer system comprising: one or more computer processors; one or more computer-readable storage media; and program instructions stored on the one or more computer-readable storage media for execution by at least one of the one or more processors, the program instructions including: program instructions for determining whether a cryptographic key is stored in a physically unclonable function (PUF) of the FPGA; in response to the cryptographic key not being stored in the PUF, program instructions for writing the cryptographic key to a tamper-resistant memory associated with a back-end of line (BEOL) of the FPGA; program instructions for writing the program key to the tamper-resistant memory; and program instructions for writing a look-up table (LUT) to the tamper-resistant memory.

[0006] Other aspects and embodiments of the present invention will become apparent from the following detailed description, which, when taken in conjunction with the drawings, illustrate by way of example the principles of the invention. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a diagram of a cloud computing environment according to an embodiment of the present invention. [Figure 2] FIG. 2 is a diagram of abstraction model layers, according to an embodiment of the present invention. [Figure 3] FIG. 1 is a diagram of a high-level architecture according to an embodiment of the present invention. [Figure 4] FIG. 2 is a diagram of an exemplary detailed architecture according to an embodiment of the present invention. [Figure 5] FIG. 2 is a diagram of an exemplary detailed architecture according to an embodiment of the present invention. [Figure 6A] 1 is a flowchart of a method according to an embodiment of the present invention. [Figure 6B] 1 is a flowchart of a method according to an embodiment of the present invention. [Figure 7]1 is a block diagram of internal and external components of a data processing system in which embodiments described herein may be implemented, in accordance with an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0008] The following description is made for the purpose of illustrating the general principles of the present invention and is not intended to limit the inventive concepts claimed herein. Moreover, particular features described herein can be used in combination with other described features, in each of the various possible combinations and permutations.

[0009] Unless otherwise specifically defined herein, all terms are to be given their broadest possible interpretation, including the meaning implied by this specification and the meaning understood by a person skilled in the art or as defined in dictionaries, treatises, etc., or both.

[0010] It should also be noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless otherwise specified. It will be further understood that the terms "comprises" and / or "comprising," as used herein, specify the presence of stated features, integers, steps, operations, elements, or components, or combinations thereof, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or groups thereof, or combinations thereof.

[0011] The following description discloses several embodiments of fabricating and reprogramming a reliable field programmable gate array (FPGA). Note that the term software as used herein includes any type of computer instructions, including but not limited to firmware, microcode, etc.

[0012] In one embodiment of the present invention, a manufacturing configuration is provided that allows programmable logic to be integrated into an FPGA in a two-step manufacturing process. In the first step, an "untrusted" semiconductor foundry can perform front-end of line (FEOL) manufacturing and application of the first metal layer. In the second step, a "trusted" semiconductor foundry can perform back-end of line (BEOL) manufacturing and memory configuration. Note that "trusted" versus "untrusted" refers to a specific manufacturer and its access to the logic associated with the FPGA's purpose. For example, access to the physical unclonable function (PUF), look-up table (LUT) data, and / or logic bit file should be reserved for the "trusted" semiconductor foundry.

[0013] In one embodiment, the BEOL memory can be designed to be tamper-resistant against attacks such as, but not limited to, side channel attacks, picosecond imaging circuit analysis (PICA) attacks, delaying attacks, and measurement attacks. In another embodiment, the BEOL memory can be used to design a PUF.

[0014] Advantages of the embodiments disclosed herein include space savings due to memory being stacked on top of the logic rather than being integrated into the FEOL, no external flash memory required, energy savings due to there being no bit files to load once the LUT is loaded, i.e. energy savings, and better performance due to FPGA "instant on" capability, i.e. no time required to load a bit file.

[0015] In one general embodiment, a computer-implemented method for producing a tamper-resistant field programmable gate array (FPGA) is provided. In one example, the computer-implemented method can write an encryption key to the tamper-resistant memory at the end of a trusted manufacturing process. The encryption key can also be stored in a cloud trusted database. In another example, the computer-implemented method can read an encryption key from a physically unclonable function (PUF), which is randomly generated based on manufacturing variations in the tamper-resistant memory, at the end of the trusted manufacturing process and store the encryption key in a cloud trusted database.

[0016] In another general embodiment, a computer-implemented method for tamper-proof remote reprogramming of a field programmable gate array (FPGA). The computer-implemented method can receive a reprogramming request for the remote FPGA. For example, the request can be generated by an application in a cloud environment responsible for software updates. Generating a random initialization vector and encrypting, by one or more processors, a programming key and a bit file with an encryption key shared with the remote FPGA. Sending, by the one or more processors, the random initialization vector, the encrypted programming key, and the encrypted bit file to the FPGA.

[0017] In another general embodiment, a computer program product for creating a tamper-resistant field programmable gate array (FPGA) includes a computer-readable storage medium embodying program instructions that are executable by a computer to cause the computer to perform the aforementioned computer-implemented method.

[0018] Although this disclosure includes detailed descriptions of cloud computing, it should be understood that implementations of the teachings recited herein are not limited to cloud computing environments. Rather, embodiments of the present invention are capable of being implemented in conjunction with any other type of computing environment now known or later developed.

[0019] Cloud computing is a service delivery model that enables convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, network bandwidth, servers, processing, memory, storage, applications, virtual machines, and services) that can be rapidly provisioned and released with minimal management effort or interaction with the service provider. This cloud model may include at least five characteristics, at least three service models, and at least four deployment models.

[0020] The characteristics are as follows:

[0021] On-demand self-service: Cloud users can unilaterally provide computing power, such as server time and network storage, automatically as needed, without the need for human interaction with the service provider.

[0022] Broad Network Access: Capabilities are available over the network and accessed through standard mechanisms that facilitate use by heterogeneous thin or thick client platforms (e.g., mobile phones, laptops, and PDAs).

[0023] Resource Pooling: A provider's computing resources are pooled to serve multiple consumers using a multi-tenant model, with dynamic allocation and reallocation of various physical and virtual resources according to demand. Location independence is meant in that consumers generally have no control or knowledge of the exact location of the resources provided, but may specify location at a higher level of abstraction (e.g., country, state, or data center).

[0024] Rapid Elasticity: Capacity can be provisioned quickly and elastically, sometimes automatically, to quickly scale out, and can be released quickly to quickly scale in. To the consumer, the capacity available for provisioning often appears unlimited, and can be purchased at any time in any amount.

[0025] Metered Services: Cloud systems automatically control and optimize resource utilization by leveraging metering capabilities at several levels of abstraction appropriate to the type of service (e.g., storage, processing, bandwidth, and active user accounts). Resource utilization can be monitored, controlled, and reported, providing transparency to both providers and consumers of the services used.

[0026] The service model is as follows:

[0027] Software as a Service (SaaS): The consumer is provided with the ability to use a provider's applications running on a cloud infrastructure. The applications are accessible from a variety of client devices through a thin-client interface, such as a web browser (e.g., web-based email). The consumer does not manage or control the underlying cloud infrastructure, including the network, servers, operating systems, storage, or possibly individual application capabilities, with the possible exception of limited user-specific application configuration settings.

[0028] Platform as a Service (PaaS): The ability provided to a consumer is to deploy consumer-created or acquired applications, created using provider-supported programming languages ​​and tools, onto a cloud infrastructure. The consumer does not manage or control the underlying cloud infrastructure, including the network, servers, operating systems, or storage, but does have control over the deployed applications and, in some cases, the configuration of the environment that hosts the applications.

[0029] Infrastructure as a Service (IaaS): The capability provided to a customer is the provision of processing, storage, networking, and other basic computing resources on which the customer can deploy and run any software, which may include operating systems and applications. The customer does not manage or control the underlying cloud infrastructure, but does have control over the operating system, storage, deployed applications, and in some cases, limited control over the selection of networking components (e.g., host firewalls).

[0030] The deployment model is as follows:

[0031] Private Cloud: The cloud infrastructure is operated solely for the organization. The cloud infrastructure may be managed by the organization or a third party and may be on-site or off-site.

[0032] Community Cloud: Cloud infrastructure is shared by several organizations and supports a unique community of shared concerns (e.g., mission, security requirements, policies, and compliance considerations). The cloud infrastructure may be managed by the organization or a third party and may be on-site or off-site.

[0033] Public Cloud: Cloud infrastructure is available to the general public or large industry organizations and is owned by organizations that sell cloud services.

[0034] Hybrid Cloud: A cloud infrastructure is a composition of two or more clouds (private, community, or public) that remain unique entities but are tied together by standard or proprietary technologies that enable data and application portability (e.g., cloud bursting for load balancing between clouds).

[0035] A cloud computing environment is service-oriented, with a focus on statelessness, loose coupling, modularity, and semantic interoperability. At the heart of cloud computing is an infrastructure that includes a network of interconnected nodes.

[0036] Referring now to FIG. 1, an illustrative cloud computing environment 50 is depicted. As shown, the cloud computing environment 50 includes one or more cloud computing nodes 10 with which local computing devices used by cloud users, such as, for example, a personal digital assistant (PDA) or cellular phone 54A, a desktop computer 54B, a laptop computer 54C, or an automobile computer system 54N, or combinations thereof, may communicate. The nodes 10 may also communicate with each other. The nodes 10 may be physically or virtually grouped in one or more networks (not shown), such as private, community, public, or hybrid clouds, or combinations thereof, as described below. This enables the cloud computing environment 50 to provide infrastructure, platform, and / or software as a service without the need for cloud users to maintain resources on their local computing devices. The types of computing devices 54A-N shown in FIG. 1 are intended to be illustrative only, and it is understood that computing node 10 and cloud computing environment 50 can communicate with any type of computerized device over any type of network and / or network-addressable connection (e.g., using a web browser).

[0037] Referring now to Figure 2, a set of functional abstraction layers provided by cloud computing environment 50 (Figure 1) is shown. It should be understood in advance that the components, layers, and functions shown in Figure 2 are intended to be illustrative only, and embodiments of the present invention are not limited thereto. As depicted, the following layers and corresponding functions are provided:

[0038] Hardware and software layer 60 includes hardware and software components. Examples of hardware components include mainframe 61, RISC (reduced instruction set computer) architecture-based servers 62, servers 63, blade servers 64, storage devices 65, and network and networking components 66. In some embodiments, software components include network application server software 67 and database software 68.

[0039] The virtualization layer 70 provides an abstraction layer within which examples of virtual entities can be provided: virtual servers 71, virtual storage 72, virtual networks including virtual private networks 73, virtual applications and operating systems 74, and virtual clients 75.

[0040] In one example, management layer 80 may provide the functions described below. Resource provisioning 81 dynamically procures computing and other resources utilized to perform tasks within the cloud computing environment. Metering and pricing 82 tracks costs as resources are utilized within the cloud computing environment and bills or invoices for the usage of these resources. In one example, these resources may include application software licenses. Security verifies the identity of cloud users and tasks and protects data and other resources. User portal 83 provides users and system administrators with access to the cloud computing environment. Service level management 84 allocates and manages cloud computing resources to meet required service levels. Service level agreement (SLA) planning and fulfillment 85 pre-provisions and procures cloud computing resources to anticipate future requirements according to SLAs.

[0041] The workload layer 90 provides examples of functions for which a cloud computing environment may be utilized. Examples of workloads and functions that may be provided from this layer include mapping and navigation 91, software development and lifecycle management 92, virtual classroom instruction delivery 93, data analytics processing 94, transaction processing 95, and reliable FPGA reprogramming 96.

[0042] It should be noted that embodiments of the present invention may operate with user permission. Any data may be collected, stored, analyzed, etc., with the user's consent. As will be understood by those skilled in the art upon reading this disclosure, in various configurations, at least some of the embodiments of the present invention are implemented as opt-in applications, plug-ins, etc.

[0043] Figure 3 is a high-level architecture for performing the various operations of Figure 5, according to various embodiments. Architecture 300 may be implemented in accordance with the present invention, in various embodiments, particularly in any of the environments depicted in Figures 1-4. Of course, more or fewer elements than those specifically illustrated in Figure 3 may be included in architecture 300, as would be understood by one of ordinary skill in the art upon reading this description.

[0044] Each of the steps of method 500 (described in further detail below) may be implemented in any suitable component of architecture 300. A processor, preferably implemented in hardware and / or software and having at least one hardware component, such as a processing circuit, chip, or module, or a combination thereof, may be utilized in any device to perform one or more steps of method 500 in architecture 300. Exemplary processors include, but are not limited to, a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or the like, combinations thereof, or any other suitable computing device known in the art.

[0045] Architecture 300 includes a block diagram illustrating an exemplary processing system for a manufacturing environment for programming FPGA devices or an environment for field reprogramming of FPGA devices to which the principles of the present invention may be applied. Architecture 300 includes a client computer 302, an FPGA programming component 308 operable on a server computer 304, and a network 306 supporting communication between client computer 302 and server computer 304.

[0046] Client computer 302 can be any computing device on which software for which an update is desired or required is installed. Client computer 302 can be a standalone computing device, an administrative server, a web server, a mobile computing device, or any other electronic device or computing system capable of receiving, sending, and processing data. In other embodiments, client computer 302 can represent a server computing system that utilizes multiple computers as a server system. In another embodiment, client computer 302 can be a laptop computer, a tablet computer, a netbook computer, a personal computer, a desktop computer, or any programmable electronic device capable of communicating with other computing devices (not shown) in a user persona generation environment via network 306.

[0047] In another embodiment, client computer 302 represents a computing system utilizing clustered computers and components (e.g., database server computers, application server computers, etc.) that function as a single pool of seamless resources when accessed within the install-time validation environment of architecture 300. Client computer 302 may include internal and external hardware components, as depicted and described in further detail with reference to FIG.

[0048] Server computer 304 can be a standalone computing device, an administrative server, a web server, a mobile computing device, or any other electronic device or computing system capable of receiving, sending, and processing data. In other embodiments, server computer 304 can represent a server computing system that utilizes multiple computers as a server system. In another embodiment, server computer 304 can be a laptop computer, a tablet computer, a netbook computer, a personal computer, a desktop computer, or any programmable electronic device capable of communicating with other computing devices (not shown) in the install-time activation environment of architecture 300 via network 306.

[0049] The network 306 may be, for example, a local area network (LAN), a wide area network (WAN) such as the Internet, or a combination of the two, and may include wired, wireless, or fiber optic connections. In general, the network 306 may be any combination of connections and protocols that support communication between the client computer 302 and the server computer 304.

[0050] In one aspect, the FPGA programming component 308 operable on the server computer 304 can program the FPGA based on a bifurcated manufacturing process. The FPGA programming component 308 can incorporate an untrusted manufacturing process and a trusted manufacturing process. In the untrusted manufacturing process, the FPGA programming component 308 can allow the substrate step (FEOL) and first metal layer portions of the FPGA to be manufactured by an untrusted manufacturer. The untrusted portion of the manufacturing does not expose any security keys or bit files to any untrusted personnel. Note that the bit file can be data associated with a look-up table (LUT) and its execution logic.

[0051] In another aspect, FPGA programming component 308 operable on server computer 304 can reprogram the FPGA in the field when needed, for example, when updated logic is available for the FPGA. FPGA programming component 308 can reprogram the FPGA using symmetric encryption over an untrusted channel and from one of two devices.

[0052] In one non-limiting example, FPGAs can be used in cloud centers as programmable hardware accelerators for artificial intelligence (AI) or other tasks in a cloud-based environment. The FPGA programming component 308 (which can be a dedicated server) can access a secure database with encryption keys and securely reprogram one or more FPGAs by encrypting and uploading new bit files. Note that a single or multiple encryption keys can be used to encrypt bit files and distribute them over a network to FPGA workers, i.e., processor and FPGA combination boards that are part of the cloud.

[0053] Note that two types of encryption keys can be employed. In one case, the encryption key can be written after trusted manufacturing is complete and then stored in a trusted database. The advantage of this approach is that multiple FPGAs can use the same encryption key, which simplifies encryption key management, bit file encryption, and distribution, thus reducing costs. The disadvantage is that if the encryption key is broken, all FPGAs that share the same encryption key are at risk.

[0054] In another case, the encryption key can be generated by a PUF function. In this case, the encryption key is generated randomly once for each FPGA based on manufacturing variations. Therefore, FPGAs have different encryption keys, with at least a very high probability that no two encryption keys are identical. The advantage is that the key does not need to be written into the FPGA. The disadvantage is that many encryption keys must be managed.

[0055] In another non-limiting example, FPGAs can be used as programmable hardware accelerators for AI or other tasks in a micro-cloud center environment. Micro-clouds enable the deployment of low-latency local services, for example, for fifth-generation (5G) cellular communication services. Thus, the FPGA programming component 308 can manage FPGA bit file updates over the network using encryption keys stored in a secure database in the cloud. The secure database and bit file repository can be managed by a private cloud. Bit files can be deployed by the private cloud to a public cloud where FPGA accelerators are deployed based on a hybrid cloud architecture.

[0056] In another non-limiting embodiment, the FPGA can be used as a programmable hardware accelerator for AI or other tasks in an Internet of Things (IoT) environment. The IoT device can be a machine, a transportation device, or any device that uses local computing. An IoT device using the embodiments described herein can be securely programmed (or reprogrammed) by the FPGA programming component 308 in a cloud environment based on the use of a cryptographic key stored in a secure database in the cloud. Note that the environment can also be an edge computing environment.

[0057] Figure 4 is an exemplary detailed architecture for performing the various operations of Figure 5, according to various embodiments. Architecture 400 may be implemented in accordance with the present invention, in various embodiments, particularly in any of the environments depicted in Figures 1-3 and 5. Of course, more or fewer elements than specifically illustrated in Figure 4 may be included in architecture 400, as would be understood by one of ordinary skill in the art upon reading this description.

[0058] Each of the steps of method 500 (described in further detail below) may be implemented in any suitable component of architecture 400. A processor, preferably implemented in hardware and / or software and having at least one hardware component, such as a processing circuit, chip, or module, or a combination thereof, may be utilized in any device to perform one or more steps of method 500 in architecture 400. Exemplary processors include, but are not limited to, a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or the like, combinations thereof, or any other suitable computing device known in the art.

[0059] Architecture 400 provides a detailed view of at least some of the modules of architecture 300. Architecture 400 can include FPGA programming component 308, which further includes manufacturing programming component 402 and field reprogramming component 404.

[0060] The manufacturing programming component 402 can program an FPGA that is partially manufactured by an untrusted manufacturer and partially manufactured by a trusted manufacturer.

[0061] The untrusted manufacturer can provide a partially fabricated FPGA, for example, the FEOL and lower level metal layers, to the manufacturing programming component 402. The trusted manufacturer can add the remaining back-end interconnect (BEOL) and upper level metal layers, including resistive random access memory (RRAM), and any non-volatile memory integrated in the BEOL, such as, but not limited to, magnetoresistive random access memory (MRAM), spin transfer (ST) MRAM, and spin transfer torque (STT) MRAM, to operate on the partially fabricated FPGA.

[0062] The manufacturing programming component 402 can embed the encryption key in a physical unclonable function (PUF) or write the encryption key to a tamper-resistant memory, such as, for example, an RRAM at a selected location in the metal layer of the back-end logic. The manufacturing programming component 402 can write the program key to a tamper-resistant memory, such as, for example, an RRAM as specified above, and write the associated LUT to the tamper-resistant memory. It should be noted that the manufacturing programming component 402 can use the LUT and the RRAM to perform any Boolean function.

[0063] For example, an 8-bit RRAM and seven 2:1 multiplexers can be used to synthesize three inputs and one output. In this example, the 2:1 multiplexers can be fabricated in the FEOL and lower-level metal by an untrusted manufacturer, and the 8-bit tamper-proof RRAM memory for the LUT can be fabricated in the upper-level metal by a trusted manufacturer.

[0064] The field reprogramming component 404 can prevent attacks such as, but not limited to, "man-in-the-middle," chip misrepresentation, and cloud misrepresentation. The field reprogramming component 404 can secure FPGA reprogramming when the communication link is unsecure, the chip is untrusted, or the server is untrusted. The field reprogramming component 404 can prevent the PUF, program key, and encryption key from being compromised even when the communication link is untrusted, the chip, or the server is untrusted.

[0065] The field reprogramming component 404 can use an untrusted channel and one of two devices, the chip or the server, as the untrusted one and securely program the FPGA using symmetric encryption. The field reprogramming component 404 can randomly generate an initialization vector before each transmission, so the bit file will be different after each encryption. Note that the encrypted programming key and bit file are unusable even if intercepted by a man-in-the-middle. Furthermore, a rogue FPGA cannot use the bit file without access to the encryption key and programming key, and a rogue cloud system cannot program the FPGA without access to the encryption key and programming key.

[0066] The field reprogramming component 404 can send a reprogramming request to the FPGA. The request can include an initialization vector, an encrypted programming key, and an encrypted bit file. Note that the encryption is performed using an encryption key known to the field reprogramming component 404 and stored in the tamper-resistant memory described above. The FPGA decrypts the programming key using the encryption key from the tamper-resistant memory and compares the decrypted programming key with the programming key stored in the tamper-resistant memory. If the two programming keys match, the FPGA decrypts the bit file and loads it into the LUT portion of the tamper-resistant memory. If the two programming keys do not match, the FPGA either does nothing or performs some random function. Note that in some situations, for example, the FPGA can be deployed before initial programming and request an update or access to the bit file. Furthermore, when an FPGA programming request is initiated by the FPGA, an initialization vector is generated by the FPGA, which requires the integration of a random generator circuit or function on the FPGA to generate the initialization vector, which must be a different number each time it is activated.

[0067] 5 is an example of an FPGA 500 having a BEOL 508 with a FEOL 506, metal layers 502 "m1-m6," and an RRAM 504. Note that the RRAM 504 may be a storage location for LUTs. Note further that the FEOL 506 may include multiplexers and flip-flops.

[0068] In one aspect, programmable logic can be integrated into both the BEOL 508 and the FEOL 506. The RRAM 504 can be designed to be tamper-resistant against side-channel attacks, picosecond imaging circuit analysis (PICA), delaying, and measurement. Additionally, the RRAM 504 can be used to design a PUF. Note that the FEOL 506 can be manufactured in an untrusted semiconductor foundry, while the BEOL 508 can be manufactured in a trusted semiconductor foundry. Another advantage of the embodiments described herein is space savings based on stacking the RRAM 504 above the logic. Embodiments of the invention, based on the use of the RRAM 504, do not require external flash memory. In some embodiments, a bit file is not needed after the LUT is loaded, which saves energy, and the FPGA has "instant-on" capabilities because no bit file loading is required.

[0069] 6A is an example flowchart of a method 600 for creating a tamper-resistant FPGA. In step 602, embodiments may determine, via manufacturing programming component 402, whether an encryption key is stored in the PUF. In step 604, if the encryption key is not stored in the PUF, embodiments may write, via manufacturing programming component 402, the encryption key to a tamper-resistant memory associated with the BEOL of the FPGA. In step 606, embodiments may write, via manufacturing programming component 402, a programming key to the tamper-resistant memory. In step 608, embodiments may write, via manufacturing programming component 402, a LUT to the tamper-resistant memory.

[0070] 6B is an example flowchart of a method 650 for tamper-resistant remote programming of an FPGA. In step 652, an embodiment may receive a reprogramming request from a remote FPGA via the field reprogramming component 404. In step 654, an embodiment may generate a random initialization vector via the field reprogramming component 404. In step 656, an embodiment may encrypt the programming key and bit file with a shared encryption key, i.e., symmetric encryption, via the field reprogramming component 404. In step 658, an embodiment may send the encrypted programming key and bit file to the FPGA via the field reprogramming component 404.

[0071] 7 depicts computer system 700, an example computer system representing client computer 302 and server computer 304. Computer system 700 includes a communications fabric 702 that provides communications between a computer processor 704, memory 706, persistent storage 708, a communications unit 710, and an input / output (I / O) interface 712. Communications fabric 702 can be implemented with any architecture designed to pass data and / or control information between processors (such as microprocessors, communications and network processors), system memory, peripheral devices, and any other hardware components in the system. For example, communications fabric 702 can be implemented with one or more buses.

[0072] Computer system 700 includes a processor 704, a cache 716, memory 706, persistent storage 708, a communication unit 710, an input / output (I / O) interface 712, and a communications fabric 702. Communications fabric 702 provides communication between cache 716, memory 706, persistent storage 708, communication unit 710, and input / output (I / O) interface 712. Communications fabric 702 can be implemented with any architecture designed to pass data and / or control information between processors (such as microprocessors, communication and network processors), system memory, peripheral devices, and any other hardware components in the system. For example, communications fabric 702 can be implemented with one or more buses or crossbar switches.

[0073] Memory 706 and persistent storage 708 are computer-readable storage media. In this embodiment, memory 706 includes random access memory (RAM). In general, memory 706 may include any suitable volatile or non-volatile computer-readable storage medium. Cache 716 is high-speed memory that enhances the performance of processor 704 by holding recently accessed data and near-recently accessed data from memory 706.

[0074] Program instructions and data used to practice embodiments of the present invention may be stored in persistent storage 708 and in memory 706 for execution by one or more of the respective processors 704 via cache 716. In an embodiment, persistent storage 708 includes a magnetic hard disk drive. Alternatively, or in addition to a magnetic hard disk drive, persistent storage 708 may include a solid-state hard drive, a semiconductor storage device, a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, or any other computer-readable storage medium capable of storing program instructions or digital information.

[0075] The media used by persistent storage 708 may also be removable. For example, a removable hard drive may be used for persistent storage 708. Other examples include optical and magnetic disks, thumb drives, and smart cards that are inserted into a drive for transfer to another computer-readable storage medium that is also part of persistent storage 708.

[0076] Communications unit 710, in these examples, provides for communication with other data processing systems or devices. In these examples, communications unit 710 includes one or more network interface cards. Communications unit 710 may provide communications through the use of either or both physical and wireless communications links. Program instructions and data used to practice embodiments of the present invention may be downloaded to persistent storage 708 via communications unit 710.

[0077] The I / O interface 712 allows for the input and output of data with other devices that may be connected to each computer system. For example, the I / O interface 712 may provide a connection to external devices 718, such as a keyboard, keypad, touch screen, or some other suitable input device, or a combination thereof. The external devices 718 may also include portable computer-readable storage media, such as thumb drives, portable optical or magnetic disks, and memory cards. Software and data used to practice embodiments of the present invention may be stored on such portable computer-readable storage media and loaded into persistent storage 708 via the I / O interface 712. The I / O interface 712 also connects to a display 720.

[0078] Display 720 provides a mechanism for displaying data to a user and may be, for example, a computer monitor.

[0079] Components described herein are identified based on the application in which they are implemented in specific embodiments of the invention. Nevertheless, it should be understood that any particular component terminology herein is used merely for convenience, and thus the invention should not be limited to use solely in any specific application identified and / or suggested by such terminology.

[0080] The present invention may be a system, method, or computer program product, or combination thereof, at any possible level of technical detail of integration. The computer program product may include a computer-readable storage medium (or media) having computer-readable program instructions for causing a processor to carry out aspects of the present invention.

[0081] A computer-readable storage medium can be a tangible device that can hold and store instructions for use by an instruction-execution device. A computer-readable storage medium can be, for example, but is not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. A non-exhaustive list of more specific examples of computer-readable storage media includes portable computer diskettes, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disk read-only memory (CD-ROM), digital versatile disk (DVD), memory sticks, floppy disks, mechanically encoded devices such as punch cards or ridge-in-groove structures having instructions recorded thereon, and any suitable combination of the foregoing. Computer-readable storage media as used herein should not be construed as being signals that are transitory in nature, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through a waveguide or other transmission medium (e.g., light pulses passing through fiber optic cable), or electrical signals transmitted through wires.

[0082] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to each computing / processing device or to an external computer or external storage device over a network, such as the Internet, a local area network, a wide area network, or a wireless network, or a combination thereof. The network may comprise copper transmission cables, optical fiber transmissions, wireless transmissions, routers, firewalls, switches, gateway computers, or edge servers, or a combination thereof. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions for storage on a computer-readable storage medium within the respective computing / processing device.

[0083] Computer-readable program instructions for carrying out operations of the present invention may be source or object code written in any combination of one or more programming languages, including assembler instructions, instruction set architecture (ISA) instructions, machine language instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, configuration data for integrated circuit devices, or object-oriented programming languages ​​such as Smalltalk®, C++, or the like, and procedural programming languages ​​such as the "C" programming language or similar programming languages. The computer-readable program instructions may execute entirely on the user's computer, partially on the user's computer, as a stand-alone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be to an external computer (e.g., through the Internet using an Internet Service Provider). In some embodiments, electronic circuitry including, for example, a programmable logic circuitry, a field programmable gate array (FPGA), or a programmable logic array (PLA) may execute computer readable program instructions by utilizing state information of the computer readable program instructions to individualize the electronic circuitry to implement aspects of the present invention.

[0084] Aspects of the present invention are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0085] These computer-readable program instructions may be provided to a processor of a computer or other programmable data processing apparatus to produce a machine, the instructions of which execute on the processor of the computer or other programmable data processing apparatus to produce means for performing the functions / acts specified in one or more blocks of the flowcharts and / or block diagrams. These computer-readable program instructions may also be stored on a computer-readable storage medium such that the computer-readable storage medium comprises an article of manufacture including instructions for performing aspects of the functions / acts specified in one or more blocks of the flowcharts and / or block diagrams, and may direct a computer, programmable data processing apparatus, or other device, or combination thereof, to function in a particular manner.

[0086] The computer-readable program instructions may also be loaded into a computer, other programmable data processing apparatus, or other device to perform a series of operational steps on the computer, other programmable apparatus, or other device to produce a computer-executed process, the instructions executing on the computer, other programmable apparatus, or other device to perform the functions / acts specified in one or more blocks of the flowcharts and / or block diagrams.

[0087] The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in the flowcharts or block diagrams may represent a module, segment, or portion of instructions, including one or more executable instructions for performing specified logical functions. In some alternative implementations, the functions noted in the blocks may occur out of the order noted in the figures. For example, two blocks shown in succession may actually be performed as a single step performed concurrently, substantially concurrently, partially, or fully in a time-overlapping manner, or the blocks may sometimes be performed in the reverse order depending on the functionality involved. It is also noted that each block in the block diagrams and / or flowchart diagrams, and combinations of blocks in the block diagrams and / or flowchart diagrams, can be implemented by a dedicated hardware-based system that performs the specified functions or acts or executes a combination of dedicated hardware and computer instructions.

[0088] Additionally, systems according to various embodiments may include a processor and logic integrated with and / or executable by the processor, where the logic is configured to perform one or more of the processing steps enumerated herein. By integrated, it is meant that the processor embeds the logic as hardware logic, such as an application-specific integrated circuit (ASIC), FPGA, etc. By executable by the processor, it is meant that the logic is hardware logic, software logic (such as firmware, part of an operating system, part of an application program), etc., or some combination of hardware and software logic that is accessible by the processor and configured to cause the processor to perform some function when executed by the processor. The software logic may be stored in any memory type, local and / or remote, as known in the art. Any processor known in the art may be used, such as a software processor module and / or a hardware processor (such as an ASIC, FPGA, central processing unit (CPU), integrated circuit (IC), graphics processing unit (GPU), etc.).

[0089] It will be apparent from the description provided above that the various features of the systems and / or methods described above may be combined in any manner to create multiple combinations.

[0090] It will further be appreciated that embodiments of the present invention may be provided in the form of a service installed on behalf of a customer to provide the service on demand.

[0091] The description of various embodiments of the present invention has been presented for purposes of illustration and is not intended to be exhaustive or limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope of the described embodiments. The terminology used herein has been chosen to best explain the principles of the embodiments, practical applications, or technical improvements over technology found in the market, or to enable those skilled in the art to understand the embodiments disclosed herein.

Claims

1. 1. A computer-implemented method for creating a tamper-resistant field programmable gate array (FPGA), the computer-implemented method comprising: determining, by one or more processors, whether a cryptographic key is stored in a physically unclonable function (PUF) of the FPGA; writing, by the one or more processors, a cryptographic key to a tamper-resistant memory associated with a back-end-of-line (BEOL) of the FPGA in response to the cryptographic key not being stored in a PUF; writing, by the one or more processors, a program key to the tamper-resistant memory; writing, by the one or more processors, a look-up table (LUT) into the tamper-resistant memory; 20. A computer-implemented method comprising:

2. 2. The computer-implemented method of claim 1, wherein the tamper-resistant memory is at least one of a resistive random access memory (RRAM), a spin transfer (ST) RRAM, or a spin transfer torque (STT) RRAM.

3. 3. The computer-implemented method of claim 1, wherein a first portion of the FPGA is fabricated at an untrusted semiconductor foundry and a remaining portion is fabricated at a trusted semiconductor foundry.

4. 4. The computer-implemented method of claim 3, wherein the first portion is a substrate end of line (FEOL) of the FPGA and the remaining portion is the BEOL of the FPGA.

5. 5. The computer-implemented method of claim 4, wherein the FPGA further comprises one or more multiplexers in the FEOL for use by the LUT.

6. 5. The computer-implemented method of claim 4, wherein the FPGA further comprises one or more flip-flops in the FEOL for use by the LUT.

7. The computer-implemented method of claim 2 , wherein the PUF is implemented in the tamper-resistant memory.

8. 8. The computer-implemented method of claim 1, wherein the encryption key is stored in a trusted database in a private cloud and written to the FPGA at a trusted facility.

9. 1. A computer system for creating a tamper-resistant field programmable gate array (FPGA), said computer system comprising: one or more computer processors; one or more computer-readable storage media; program instructions stored on the one or more computer-readable storage media for execution by at least one of the one or more processors, the program instructions comprising: program instructions for determining whether a cryptographic key is stored in a physically unclonable function (PUF) of the FPGA; responsive to the cryptographic key not being stored in a PUF, program instructions for writing the cryptographic key to a tamper-resistant memory associated with a back-end-of-line (BEOL) of the FPGA; program instructions for writing a program key to the tamper-resistant memory; and Program instructions for writing a look-up table (LUT) into said tamper-resistant memory. the program instructions including: A computer system comprising:

10. 10. The system of claim 9, wherein the tamper-resistant memory is at least one of a resistive random access memory (RRAM), a spin transfer (ST) RRAM, or a spin transfer torque (STT) RRAM.

11. 10. The system of claim 9, wherein the FPGA's front end of line (FEOL) is fabricated in an untrusted semiconductor foundry and the BEOL is fabricated in a trusted semiconductor foundry.

12. 12. The system of claim 11, wherein the FPGA further comprises one or more multiplexers in the FEOL for use by the LUT and one or more flip-flops in the FEOL for use by the LUT.

13. The system of claim 9 , wherein the PUF is implemented in the tamper-resistant memory.

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