Sharing Encrypted Documents Within and Outside an Organization

• US 20200136812A1
• Filed: 12/30/2019
• Published: 04/30/2020
• Est. Priority Date: 08/10/2016
• Status: Active Grant

• Current Assignee: Nextlabs
• Original Assignee: Nextlabs
• Inventors: Lim, Keng, Fung, Poon
• Granted Patent: US 10,911,223 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 21/602 Providing cryptographic facilities or services
• CPC Class Codes: G06F 21/6218 to a system of files or objects, e.g. local or distributed file system or database
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 63/0442 wherein the sending and receiving network entities apply asymmetric encryption, i.e. different keys for encryption and decryption cryptographic mechanisms or cryptographic arrangements for public-key encryption H04L9/30
• CPC Class Codes: H04L 63/061 for key exchange, e.g. in peer-to-peer networks cryptographic mechanisms or cryptographic arrangements for key agreement H04L9/0838
• CPC Class Codes: H04L 63/062 for key distribution, e.g. centrally by trusted party cryptographic mechanisms or cryptographic arrangements for key distribution involving a central third party H04L9/0819
• CPC Class Codes: H04L 63/12 Applying verification of the received information cryptographic mechanisms or cryptographic arrangements for data integrity or data verification H04L9/32
• CPC Class Codes: H04L 9/08 Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords network architectures or network communication protocols for supporting key management in a packet data network H04L63/06
• CPC Class Codes: H04L 9/0822 using key encryption key
• CPC Class Codes: H04L 9/0866 involving user or device identifiers, e.g. serial number, physical or biometrical information, DNA, hand-signature or measurable physical characteristics
• CPC Class Codes: H04L 9/0894 Escrow, recovery or storing of secret information, e.g. secret key escrow or cryptographic key storage

Abstract

A method and system of creating and managing encryption keys that facilitates sharing of encrypted content. The system may include an information management system with a key management server and a computing device having an encryption service module. The encryption service module detects operations at the computing device and encrypts a document with an encryption key created using user information and a secret.

Claims

1. A method comprises:

providing an information management system having a key management server, a first computing device and a second computing device;

providing the key management server having a first secret and a first seed token;

providing the first computing device having a first encryption service module, wherein the first encryption service module having a second secret and a second seed token;

providing the second computing device having a second encryption service module;

detecting a file save operation on a document by the first encryption service module;

at the first encryption service module, collecting user information;

at the first encryption service module, creating a document identifier for the document;

at the first encryption service module, creating a first encryption key with the document identifier, the user information, the second seed token and the second secret;

at the first encryption service module, creating a second encryption key;

at the first encryption service module, encrypting the document with the second encryption key to produce encrypted content;

at the first encryption service module, encrypting the second encryption key with the first encryption key to produce an encrypted second encryption key;

at the first encryption service module, storing the document identifier, the user information, the first seed token, the second seed token, the encrypted second encryption key and the encrypted content in an encrypted document;

detecting a file open operation on the encrypted document by the second encryption service module;

at the second encryption service module, retrieving the document identifier, the user information and the first seed token in the encrypted document;

at the second encryption service module, sending the document identifier, the user information and the first seed token to the key management server;

at the key management server, creating a third encryption key with the document identifier, the user information, the first seed token and the first secret;

at the second encryption service module, receiving the third encryption key from the key management server;

at the second encryption service module, decrypting encrypted second encryption key in the encrypted document with the third encryption key to produce a fourth encryption key; and

at the second encryption service module, decrypting encrypted content in the encrypted document with the fourth encryption key to produce unencrypted content.

2. The method of claim 1 wherein the first secret and the second secret are symmetric keys.

3. The method of claim 1 wherein the first seed token and the second seed token are different.

4. The method of claim 1 wherein the first secret and the second secret are different.

5. The method of claim 1 wherein the first encryption key and the third encryption key are identical.

6. The method of claim 1 wherein the first encryption key is not stored on the key management server.

7. The method of claim 1 wherein the second encryption key is a symmetric key.

8. The method of claim 1 wherein the second encryption key and the fourth encryption key are identical.

9. The method of claim 1 wherein the detecting a file save operation on a document by the first encryption service module is performed using code injection.

10. The method of claim 1 wherein the detecting a file save operation on a document by the first encryption service module occurs in a process of an application program, wherein the application program invokes the file save operation.

11. The method of claim 1 wherein the user information comprises a digital certificate.

12. The method of claim 1 wherein the document identifier is a universally unique identifier.

13. The method of claim 1 wherein the detecting a file open operation on a document by the second encryption service module is performed using code injection.

14. The method of claim 1 wherein the detecting a file open operation on a document by the second encryption service module occurs in a process of an application program, wherein the application program invokes the file open operation.

15. A method comprises:

providing an information management system having a key management server and a computing device, wherein a user has logged on to the computing device;

providing the key management server having a first secret and a first seed token;

providing the computing device having an encryption service module, wherein the encryption service module having a second secret and a second seed token;

detecting a file save operation on a document by the encryption service module;

at the encryption service module, collecting user information;

at the encryption service module, creating a document identifier for the document;

at the encryption service module, creating a first encryption key with the document identifier, the user information, the second seed token and the second secret;

at the encryption service module, creating a second encryption key;

at the encryption service module, encrypting the document with the second encryption key to produce encrypted content;

at the encryption service module, encrypting the second encryption key with the first encryption key to produce an encrypted second encryption key;

at the encryption service module, storing the document identifier, the user information, the first seed token, the second seed token, the encrypted second encryption key and the encrypted content in an encrypted document;

detecting a file open operation on the encrypted document by the encryption service module;

at the encryption service module, retrieving the document identifier, the user information, the first seed token and the second seed token in the encrypted document;

at the encryption service module, if the user information identifies the user, creating a third encryption key with the document identifier, the user information, the second seed token and the second secret;

at the encryption service module, if the user information does not identify the user, sending the document identifier, the user information and the first seed token to the key management server;

at the key management server, creating a third encryption key with the document identifier, the user information, the first seed token and the first secret;

at the encryption service module, if the user information does not identify the user, receiving the third encryption key from the key management server;

at the encryption service module, decrypting encrypted second encryption key in the encrypted document with the third encryption key to produce a fourth encryption key; and

at the encryption service module, decrypting encrypted content in the encrypted document with the fourth encryption key to produce unencrypted content.

16. The method of claim 15 wherein the first secret and the second secret are symmetric keys.

17. The method of claim 15 wherein the first secret and the second secret are different.

18. The method of claim 15 wherein the first seed token and the second seed token are different.

19. The method of claim 15 wherein the first encryption key and the third encryption key are identical.

20. The method of claim 15 wherein the first encryption key is not stored on the key management server.

21. The method of claim 15 wherein the second encryption key is a symmetric key.

22. The method of claim 15 wherein the second encryption key and the fourth encryption key are identical.

23. The method of claim 15 wherein the detecting a file save operation on a document by the encryption service module is performed using code injection.

24. The method of claim 15 wherein the detecting a file save operation on a document by the encryption service module occurs in a process of an application program, wherein the application program invokes the file save operation.

25. The method of claim 15 wherein the user information comprises a digital certificate.

26. The method of claim 15 wherein the document identifier is a universally unique identifier.

27. The method of claim 15 wherein the detecting a file open operation on a document by the encryption service module is performed using code injection.

28. The method of claim 15 wherein the detecting a file open operation on a document by the encryption service module occurs in a process of an application program, wherein the application program invokes the file open operation.