Method for selective encryption within documents

• US 20050235163A1
• Filed: 04/15/2004
• Published: 10/20/2005
• Est. Priority Date: 04/15/2004
• Status: Active Grant

• Current Assignee: Kyndryl Incorporated (Kyndryl Holdings, Inc.)
• Original Assignee: International Business Machines Corporation
• Inventors: Forlenza, Randolph Michael, Berstis, Viktors
• Granted Patent: US 7,484,107 B2
• Time in Patent Office: Days
• US Class Current: 713/193
• CPC Class Codes: G06F 21/6209 to a single file or object, e.g. in a secure envelope, encrypted and accessed using a key, or with access control rules appended to the object itself
• CPC Class Codes: G06F 2221/2107 File encryption
• CPC Class Codes: G06F 2221/2113 Multi-level security, e.g. mandatory access control
• CPC Class Codes: G06F 2221/2149 Restricted operating environment
• CPC Class Codes: H04L 2209/60 Digital content management, e.g. content distribution
• CPC Class Codes: H04L 9/088 Usage controlling of secret information, e.g. techniques for restricting cryptographic keys to pre-authorized uses, different access levels, validity of crypto-period, different key- or password length, or different strong and weak cryptographic algorithms network architectures or network communication protocols for using time-dependent keys in a packet data network H04L63/068
• CPC Class Codes: H04L 9/14 using a plurality of keys or algorithms

Abstract

The present invention allows the user (author or creator) of a document to specify that certain portions of a document be selected for encryption while other portions of the document remain displayed as created. In addition, each encrypted section could have multiple encryption keys such that some viewers can review certain parts of the document while other viewers will not have that same access. The user could employ a standard word processing editor technique to highlight (or swipe) portions of a document that the user desires to be encrypted. The highlighted portion would then be ‘tagged’ with a surrounding attribute indicating to the word processor that this highlighted portion of the document is to be encrypted. The highlighted sections would also have encryption keys associated with the highlighted and encrypted section. Any one of the encryption keys for that section would decrypt that section. With proper authorization, any encrypted portion of a document would be displayed as part of the document. Without proper authorization, the display of the document would only contain the unencrypted portions of the document.

Claims

1. A method for selective encryption within a document comprising the steps of:

detecting a first section of a document selected and marked for encryption;

detecting at least one additional section of the document selected and marked for encryption; and

encrypting at least one of said detected document section copies with at least two different encryption keys.

2. The method as described in claim 1 further comprising after said encrypting step, the step of displaying the document with the selected portions of the document encrypted.

3. The method as described in claim 2 wherein the encrypted portions are displayed in a random unintelligible format until a proper decryption key is entered.

4. The method as described in claim 2 further comprising after said displaying step, the step of repeating said detecting and encrypting steps for another selective portion of the document.

5. The method as described in claim 2 further comprising after said displaying step, the step of storing the document with the selected portions encrypted.

6. The method as described in claim 5 further comprising after said storing step, the steps of:

detecting an attempt to access an encrypted portion of the document; and

determining whether the accessor is authorized to access the encrypted portion of the document.

7. The method as described in claim 6 wherein said authorization-determining step further comprises matching the encryption supplied by the accessor with at least one of the encryption keys for the document section for which access is attempted.

8. The method as described in claim 7 further comprising the step of displaying the document with any previously encrypted portions decrypted when the determination is that the accessor has the authority to access the encrypted portion of the document.

9. The method as described in claim 2 further comprising after said displaying step, the step of transmitting the document across a computing network to an identified destination.

10. The method as described in claim 1 wherein each encrypted section of the document has one encryption key that is used in more than one the encryption sections of the document.

11. The method as described in claim 1 wherein said detecting step further comprises identifying a selected portion of a document that is marked by swiping a peripheral apparatus that interfaces with a computing device over the portion of the document for which encryption is desired.

24. The method as described in claim 1 further comprising the step of encrypting at least one of other section of the document with at least one encryption key.

12. A computer program product in a computer readable medium for selective encryption within a document comprising:

instructions for detecting a first section of a document selected and marked for encryption;

instructions for detecting at least one additional section of the document selected and marked for encryption;

instructions for encrypting at least one of said detected document sections with at least two different encryption keys; and

encrypting at least one of other said section with at least one encryption key.

13. The computer program product as described in claim 12 further comprising after said encrypting instructions, instructions for displaying the document with the selected portions of the document encrypted.

14. The computer program product as described in claim 13 wherein the encrypted portions are displayed in a random unintelligible format until a proper decryption key is entered.

15. The computer program product as described in claim 12 further comprising after said displaying instructions, instructions for repeating said detecting and encrypting instructions for another selective portion of the document.

16. The computer program product as described in claim 12 further comprising after said displaying instructions, instructions for storing the document with the selected portions encrypted.

17. The method as described in claim 16 further comprising after said storing instructions, instructions for:

detecting an attempt to access an encrypted portion of the document; and

determining whether the accessor is authorized to access the encrypted portion of the document.

18. The computer program product as described in claim 17 wherein said authorization-determining instructions further comprise matching the encryption supplied by the accessor with at least one of the encryption keys for the document section for which access is attempted.

19. The method as described in claim 18 further comprising instructions for displaying the document with any previously encrypted portions decrypted when the determination is that the accessor has the authority to access the encrypted portion of the document.

20. The computer program product as described in claim 12 further comprising after said displaying instructions, instructions for transmitting the document across a computing network to an identified destination.

21. The computer program product described in claim 12 wherein each encrypted section of the document has one encryption key that is used in more than one of the encryption sections of the document.

22. A method for selective encryption within a document comprising the steps of:

detecting a first section of a document selected and marked for encryption;

detecting at least one additional section of the document selected and marked for encryption;

adding a character string to the text of a section of the document selected for encryption; and

encrypting a selected section of the document with at least two different encryption keys.

23. The method as described in claim 22 further comprising the step of encrypting at least one of other section of the document with at least one encryption key.