Securely recovering a computing device

• US 10,142,104 B2
• Filed: 06/09/2017
• Issued: 11/27/2018
• Est. Priority Date: 01/07/2007
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: De Atley, Dallas Blake, De Cesare, Joshua, Smith, Michael, Reda, Matthew, Sen, Shantonu, Wright, John Andrew
• Primary Examiner(s): Brown, Anthony D
• Assistant Examiner(s): Anderson, Michael D
• Application Number:
  US15/619,276
• Publication Number:
  US 20170346631A1
• Time in Patent Office: 536 Days
• Field of Search: 713187
• CPC Class Codes: G06F 11/1417 Boot up procedures
• 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 21/572 Secure firmware programming, e.g. of basic input output system [BIOS]
• CPC Class Codes: G06F 21/575 Secure boot
• CPC Class Codes: G06F 21/64 Protecting data integrity, e.g. using checksums, certificates or signatures
• CPC Class Codes: H04L 63/06 for supporting key management in a packet data network cryptographic mechanisms or cryptographic arrangements for key management H04L9/08
• CPC Class Codes: H04L 63/08 for authentication of entities cryptographic mechanisms or cryptographic arrangements for entity authentication H04L9/32
• CPC Class Codes: H04L 9/14 using a plurality of keys or algorithms
• CPC Class Codes: H04L 9/302 involving the integer factorization problem, e.g. RSA or quadratic sieve [QS] schemes
• CPC Class Codes: H04L 9/3239 involving non-keyed hash functions, e.g. modification detection codes [MDCs], MD5, SHA or RIPEMD
• CPC Class Codes: H04L 9/3247 involving digital signatures
• CPC Class Codes: H04L 9/3249 using RSA or related signature schemes, e.g. Rabin scheme

Abstract

A method and an apparatus for establishing an operating environment by certifying a code image received from a host over a communication link are described. The code image may be digitally signed through a central authority server. Certification of the code image may be determined by a fingerprint embedded within a secure storage area such as a ROM (read only memory) of the portable device based on a public key certification process. A certified code image may be assigned a hash signature to be stored in a storage of the portable device. An operating environment of the portable device may be established after executing the certified code.

Claims

1. A method for updating an application established at a file system of a client device, the method comprising, at the client device:

providing a request to a computing device to update the application, wherein the request includes a version identifier associated with the application;

loading a code image that is received from the computing device into a storage device of the client device, wherein the code image is (i) digitally signed by a signature, (ii) associated with an application package, and (iii) based on the version identifier;

verifying that the code image is trusted by certifying a fingerprint stored in a secure memory of the client device, wherein the fingerprint is associated with a unique device identifier of the client device; and

in response to determining that the code image is trusted;

verifying that an integrity of one or more files of the application package is not compromised, and

establishing the one or more files at the file system by executing the code image; and

in response to determining that the code image is not trusted;

disabling access to the unique device identifier such as to prevent access to user data associated with the client device, and

removing the code image from the storage device.

2. The method of claim 1, wherein, subsequent to establishing the one or more files at the file system, the method further comprises:

rebooting an operating system of the client device.

3. The method of claim 1, wherein, in response to determining that the integrity of the one or more files is compromised, the method further comprises:

preventing the one or more files from being established at the file system.

4. The method of claim 1, wherein determining that the code image is trusted further comprises:

verifying the signature of the code image by using the fingerprint.

5. The method of claim 1, wherein, in response to determining that the code image is not trusted, the method further comprises:

entering a Device Firmware Upgrade (DFU) mode to perform system management tasks.

6. The method of claim 1, wherein the client device derives a hash value from the code image that is based on the unique device identifier.

7. The method of claim 1, wherein the fingerprint is based on a public key.

8. The method of claim 1, wherein, subsequent to determining that the code image is not trusted, the method further comprises:

determining whether the unique device identifier is active; and

in response to determining that the unique device identifier is inactive;

preventing access to device hardware associated with the client device.

9. A system for updating an application, the system comprising:

at least one processor; and

at least one memory storing instructions, that when executed by the at least one processor, cause the system to;

provide a request to a computing device to update the application, wherein the request includes a version identifier associated with the application;

load a code image that is received from the computing device into a storage device of the system, wherein the code image is (i) digitally signed by a signature, (ii) associated with an application package, and (iii) based on the version identifier;

verify that the code image is trusted by certifying a fingerprint stored in a secure memory of the system, wherein the fingerprint is associated with a unique device identifier of the system; and

in response to determining that the code image is trusted;

verify that an integrity of one or more files of the application package is not compromised, and

establish the one or more files at a file system of the system by executing the code image; and

in response to determining that the code image is not trusted;

disable access to the unique device identifier such as to prevent access to user data associated with the system, and

remove the code image from the storage device.

10. The system of claim 9, wherein, subsequent to establishing the one or more files at the file system, the at least one processor further causes the system to:

reboot an operating system of the system.

11. The system of claim 9, wherein, in response to determining that the integrity of the one or more files is compromised, the at least one processor further causes the system to:

prevent the one or more files from being established at the file system.

12. The system of claim 9, wherein determining that the code image is trusted further comprises:

verifying the signature of the code image by using the fingerprint.

13. The system of claim 9, wherein, in response to determining that the code image is not trusted, the at least one processor further causes the system to:

enter a Device Firmware Upgrade (DFU) mode to perform system management tasks.

14. The system of claim 9, wherein the system derives a hash value from the code image that is based on the unique device identifier.

15. The system of claim 9, wherein, subsequent to determining that the code image is not trusted, the at least one processor further causes the system to:

determine whether the unique device identifier is active; and

in response to determining that the unique device identifier is inactive;

prevent access to device hardware associated with the system.

16. At least one non-transitory computer readable storage medium configured to store instructions that, when executed by at least one processor included in a computing device, cause the computing device to:

provide a request to a host computing device to update an application established at a file system of the computing device, wherein the request includes a version identifier associated with the application;

load a code image that is received from the host computing device into a storage device of the computing device, wherein the code image is (i) digitally signed by a signature, (ii) associated with an application package, and (iii) based on the version identifier;

verify that the code image is trusted by certifying a fingerprint stored in a secure memory of the computing device, wherein the fingerprint is associated with a unique device identifier of the computing device; and

in response to determining that the code image is trusted;

verify that an integrity of one or more files of the application package is not compromised, and

establish the one or more files at the file system by executing the code image; and

in response to determining that the code image is not trusted;

disable access to the unique device identifier such as to prevent access to user data associated with the file system, and

remove the code image from the storage device.

17. The at least one non-transitory computer readable storage medium of claim 16, wherein, subsequent to establishing the one or more files at the file system, the at least one processor further causes the computing device to:

reboot an operating system of the computing device.

18. The at least one non-transitory computer readable storage medium of claim 16, wherein, in response to determining that the integrity of the one or more files is compromised, the at least one processor further causes the computing device to:

prevent the one or more files from being established at the file system.

19. The at least one non-transitory computer readable storage medium of claim 16, wherein determining that the code image is trusted further comprises:

verifying the signature of the code image by using the fingerprint.

20. The at least one non-transitory computer readable storage medium of claim 16, wherein the fingerprint is based on a public key.