Saving and retrieving data based on public key encryption

• US 8,621,243 B2
• Filed: 01/27/2011
• Issued: 12/31/2013
• Est. Priority Date: 04/17/2002
• Status: Expired due to Fees

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: England, Paul, Peinado, Marcus
• Primary Examiner(s): Parthasarathy, Pramila
• Application Number:
  US13/015,402
• Publication Number:
  US 20110119501A1
• Time in Patent Office: 1,069 Days
• Field of Search: None
• US Class Current: 713/193
• CPC Class Codes: G06F 21/6218 to a system of files or objects, e.g. local or distributed file system or database

Abstract

In accordance with certain aspects, data is received from a calling program. Ciphertext that includes the data is generated, using public key encryption, in a manner that allows the data to be obtained from the ciphertext only if one or more conditions are satisfied. In accordance with another aspect, a bit string is received from a calling program. Data in the bit string is decrypted using public key decryption and returned to the calling program only if one or more conditions included in the bit string are satisfied.

Claims

1. A computing device having one or more components implemented at least in part in hardware and that perform acts comprising:

obtaining data to be sealed and one or more conditions that are to be satisfied in order for the data to be unsealed;

sealing the data in response to a request by a caller by encrypting, in the computing device and using public key encryption, both the data and the one or more conditions to generate a ciphertext that includes both the encrypted data and the encrypted one or more conditions, the data not being unsealed if the one or more conditions are not satisfied, the one or more conditions including a program to be executed and the one or more conditions being satisfied only if execution of the program returns an indication of true; and

returning the ciphertext to the caller.

2. A computing device as recited in claim 1, the data comprising a cryptographic key.

3. A computing device as recited in claim 1, the obtaining the data comprising receiving the data as part of a PKSeal operation.

4. A computing device as recited in claim 1, the program having been written in a scripting language.

5. A computing device as recited in claim 1, the program comprising a set of computer-executable instructions written in a programming language.

6. A method comprising:

invoking, in a device, an operation of a guard to seal data; and

receiving, in response to invoking the operation, a ciphertext generated by the guard when sealing the data, the ciphertext including both the data and one or more conditions that are to be satisfied in order for the data to be unsealed, the one or more conditions including a program to be executed and the one or more conditions being satisfied only if execution of the program returns an indication of true, the data not being unsealed if the one or more conditions are not satisfied, the data and the one or more conditions having been encrypted using public key encryption.

7. A method as recited in claim 6, the operation comprising a PKSeal operation.

8. A method as recited in claim 6, the invoking the operation comprising passing the data as an input to the operation.

9. A method as recited in claim 6, the invoking the operation comprising passing at least one of the one or more conditions as an input to the operation.

10. A method as recited in claim 6, the data comprising a cryptographic key.

11. A method as recited in claim 6, the program having been written in a scripting language.

12. A method as recited in claim 6, the program comprising a set of computer readable instructions written in a programming language.

13. A method comprising:

invoking, in a device, an operation of a guard to have ciphertext decrypted; and

receiving from the guard, in response to invoking the operation, decrypted data from the ciphertext only if one or more conditions included in the ciphertext are satisfied, the one or more conditions including a program and the one or more conditions being satisfied only if execution of the program returns an indication of true, the ciphertext being decrypted using public key decryption.

14. A method as recited in claim 13, the operation comprising a PKUnseal operation.

15. A method as recited in claim 13, the invoking the operation comprising passing the ciphertext as an input to the operation.

16. A method as recited in claim 13, the invoking the operation comprising passing a pointer to the ciphertext as an input to the operation.

17. A method as recited in claim 13, the data comprising a cryptographic key.

18. A method as recited in claim 13, the program having been written in a scripting language.

19. A method as recited in claim 13, the program comprising a set of computer readable instructions written in a programming language.