Thresholds on scripts executable by unified extensible firmware interface systems

• US 10,587,422 B2
• Filed: 01/28/2016
• Issued: 03/10/2020
• Est. Priority Date: 01/28/2016
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Dias Correa, Rodrigo, Cagnini Ciocari, Juliano Francisco, Cardoso Novaes, Reynaldo, Santos, Anellena, Mayer, Karyne
• Primary Examiner(s): Plecha, Thaddeus J
• Application Number:
  US15/763,020
• Publication Number:
  US 20190089545A1
• Time in Patent Office: 1,503 Days
• CPC Class Codes: G06F 21/51 at application loading time, e.g. accepting, rejecting, starting or inhibiting executable software based on integrity or source reliability
• CPC Class Codes: G06F 21/53 by executing in a restricted environment, e.g. sandbox or secure virtual machine
• CPC Class Codes: G06F 21/57 Certifying or maintaining trusted computer platforms, e.g. secure boots or power-downs, version controls, system software checks, secure updates or assessing vulnerabilities
• CPC Class Codes: G06F 21/575 Secure boot
• CPC Class Codes: G06F 2221/034 Test or assess a computer or a system
• CPC Class Codes: G06F 9/4401 Bootstrapping security arrangements therefor G06F21/57
• CPC Class Codes: G06F 9/45512 Command shells
• CPC Class Codes: H04L 63/0823 using certificates cryptographic mechanisms or cryptographic arrangements for entity authentication involving certificates H04L9/3263
• CPC Class Codes: H04L 63/126 the source of the received data
• CPC Class Codes: H04L 9/30 Public key, i.e. encryption algorithm being computationally infeasible to invert or user's encryption keys not requiring secrecy
• CPC Class Codes: H04L 9/3268 using certificate validation, registration, distribution or revocation, e.g. certificate revocation list [CRL]

Abstract

In an example, an apparatus compatible with a unified extensible firmware interface (UEFI) system includes a processor resource and a computer-readable storage device with a set of instructions stored thereon. In that example, the instructions are executable to cause the UEFI system to verify an integrity status of a script file and an authenticity status of the script file, analyze contents of the script file in response to a determination that the script is authentic, establish a threshold on execution of the script file based on the analysis of the contents, and execute a control program concurrent with execution of the script to implement the threshold.

Claims

1. A system comprising:

an authentication engine comprising circuitry to determine a source of a script and an integrity level of the script;

a primitives engine comprising circuitry to enable a plurality of primitives to use with the script, the plurality of primitives to define functionalities available via a unified extensible firmware interface (UEFI) system; and

an environment engine comprising circuitry to;

enable execution of the script during initialization of a target device in response to a determination that the script is authenticated based on the source and the integrity level; and

establish execution parameters of the script by the UEFI system based on thresholds defined by a plurality of control programs.

2. The system of claim 1, wherein:

the authentication engine is to download the script from a server repository; and

the environment engine is to restrict execution of the script to the functionalities of the plurality of primitives.

3. The system of claim 2, wherein the authentication engine is to:

provide a first interface to designate a uniform resource identifier of the server repository; and

provide a second interface to designate a non-volatile memory resource to store the script.

4. The system of claim 1, wherein the environment engine further comprises:

an interpreter engine comprising circuitry to analyze script content; and

an execution engine comprising circuitry to execute the script in a runtime environment with the plurality of control programs executing to check operation of the script during runtime to be within resource usage parameters represented by the thresholds.

5. The system of claim 4, wherein:

the interpreter engine is to identify a function call that is not a functionality of the plurality of primitives; and

the execution engine is to forbid execution of the script in response to a determination that the script contains the function call.

15. The apparatus of claim 1, wherein the set of instructions is executable by the processor resource to cause the UEFI system to:

enable the language interpreter to access a UEFI application programming interface; and

execute the language interpreter to identify whether a set of actions of the script file match a device profile of the apparatus.

6. A non-transitory computer-readable storage medium comprising a set of instructions executable by a processor resource to:

authenticate a script source against a digital certificate;

interpret a script to run on a set of primitives, the set of primitives to represent functionalities available via a unified extensible firmware interface (UEFI) system;

execute the script via the UEFI system according to a plurality of thresholds associated with the set of primitives in response to a determination that the script achieves an integrity level; and

check, via the UEFI system, events produced by execution of the script to identify that the script is executing within limits defined by the plurality of thresholds.

7. The medium of claim 6, wherein the set of instructions is executable by the processor resource to:

determine a uniform resource locator (URL) from a statically-defined identifier or a user-provided identifier; and

download the script from a server repository via the URL.

8. The medium of claim 7, wherein the set of instructions is executable by the processor resource to:

select the script to download from the server repository based on a target device profile, the target device profile containing a configuration identifier of a target device;

check the script source by using a public encryption key against the digital certificate; and

cancel a download operation of the script in response to a determination that the script source is not authenticated.

9. The medium of claim 6, wherein the set of instructions is executable by the processor resource to:

terminate, via the UEFI system, execution of the script in response to a determination that an event occurred that indicates a functionality is requested to perform beyond the thresholds.

10. The medium of claim 6, wherein the set of instructions is executable by the processor resource to:

identify a function call of the script to be performed in response to a particular UEFI event; and

execute the function call in response to the particular UEFI event.

11. An apparatus compatible with a unified extensible firmware interface (UEFI) system comprising:

a processor resource;

a non-transitory computer readable storage device comprising a set of instructions executable by the processor resource to cause the UEFI system to;

verify an integrity status of a script file and authenticity status of the script file using a public encryption key, the script file representing a script executable on the UEFI system;

analyze, via a language interpreter, contents of the script file in response to a determination that the script file is authentic;

establish a threshold on execution of the script file based on the analysis of the contents; and

execute a control program concurrent with execution of the script, the control program to implement the threshold.

12. The apparatus of claim 11, wherein the set of instructions is executable by the processor resource to cause the UEFI system to:

check whether a uniform resource locator (URL) to a remotely located repository exists on the apparatus; and

retrieve a script file from the repository at the URL using a transfer protocol.

13. The apparatus of claim 11, wherein the set of instructions is executable by the processor resource to cause the UEFI system to:

determine whether a file hash of the script is authentic; and

prevent the apparatus from executing the script in response to a determination that the file hash is not authentic.

14. The apparatus of claim 11, wherein the set of instructions is executable by the processor resource to cause the UEFI system to:

deny execution of an operation of the script file in response to a determination that the operation is to perform outside a parameter of execution; and

deny execution of the operation of the script file in response to a comparison of the operation to a list of primitives allowable by the UEFI system.