Method and system for authentication information decryption for .ZIP files

• US 20050097113A1
• Filed: 09/20/2004
• Published: 05/05/2005
• Est. Priority Date: 07/16/2003
• Status: Abandoned Application

• Current Assignee: PKWARE, Inc. (PKW Holdings, Inc.)
• Original Assignee: PKWARE, Inc. (PKW Holdings, Inc.)
• Inventors: Peterson, James C.
• Application Number:
  US10/946,454
• Publication Number:
  US 20050097113A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/1744 using compression, e.g. sparse files
• 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 21/6218 to a system of files or objects, e.g. local or distributed file system or database
• CPC Class Codes: G06F 2221/2107 File encryption
• CPC Class Codes: G06F 2221/2153 Using hardware token as a secondary aspect
• CPC Class Codes: H04L 2209/30 Compression, e.g. Merkle-Damgard construction
• CPC Class Codes: H04L 9/0819 Key transport or distribution, i.e. key establishment techniques where one party creates or otherwise obtains a secret value, and securely transfers it to the other(s) network architectures or network communication protocols for key distribution in a packet data network H04L63/062
• 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

Abstract

The present invention provides a method of integrating existing strong encryption methods into the processing of a .ZIP file to provide a highly secure data container which provides flexibility in the use of symmetric and asymmetric encryption technology. The present invention adapts the well established .ZIP file format to support higher levels of security and multiple methods of data encryption and key management, thereby producing a highly secure and flexible digital container for electronically storing and transferring confidential data.

Claims

1. A method of authenticating a data file in a .Zip file format data container, said method including:

receiving a data container constructed in accordance with a .Zip file format, said data container including;

a data file; and

authentication information with regard to said data file;

using said authentication information to authenticate at least one of the originator of said data file and the integrity of said data file.

2. The method of claim 1 wherein said authentication information is asymmetrically decrypted using an asymmetric key before said authentication information is used.

3. The method of claim 1 wherein said asymmetric decryption employs a public key.

4. The method of claim 1 wherein said asymmetric decryption employs a X.509 digital certificate.

5. The method of claim 1 wherein said data file is an encrypted data file further including decrypting said encrypted data file to form a decrypted data file.

6. The method of claim 5 wherein said data file is decrypted using symmetric decryption.

7. The method of claim 5 wherein said data file is decrypted using asymmetric decryption.

8. The method of claim 5 further including decompressing said decrypted data file after decrypting.

9. The method of claim 8 wherein said data file is decompressed using a Lempel-Ziv (LZ)-type data decompression algorithm.

10. The method of claim 8 wherein said data file is decompressed using a Deflate-type data decompression algorithm.

11. The method of claim 8 wherein said data file is decompressed using a Burrows-Wheeler Transform (BWT)-type data decompression algorithm.

12. The method of claim 5 wherein said data file is not decompressed.

13. The method of claim 1 wherein said authentication information includes a time stamp representing the time at which authentication information was associated with said data file.

14. The method of claim 1 wherein said authentication information is based on a hash calculated for said data file.

15. The method of claim 1 wherein said authentication information is based on a cryptographic checksum.

16. The method of claim 1 wherein said authentication information is based on hash data that is asymmetrically decryptable using a public key.

17. A method of authenticating a data file in a data container, said method including:

receiving a data container designed for containing compressed files, said data container including;

a data file; and

authentication information with regard to said data file;

using said authentication information to authenticate at least one of the originator of said data file and the integrity of said data file.

18. The method of claim 17 wherein said authentication information is asymmetrically decrypted using an asymmetric key before said authentication information is used.

19. The method of claim 18 wherein said asymmetric decryption employs a public key.

20. The method of claim 18 wherein said asymmetric decryption employs a X.509 digital certificate.

21. The method of claim 17 wherein said data file is an encrypted data file, further including decrypting said encrypted data file to form a decrypted data file.

22. The method of claim 21 wherein said data file is decrypted using symmetric decryption.

23. The method of claim 21 wherein said data file is decrypted using asymmetric decryption.

24. The method of claim 21 further including decompressing said decrypted data file after decrypting.

25. The method of claim 24 wherein said data file is decompressed using a Lempel-Ziv (LZ)-type data decompression algorithm.

26. The method of claim 24 wherein said data file is decompressed using a Deflate-type data decompression algorithm.

27. The method of claim 24 wherein said data file is decompressed using a Burrows-Wheeler Transform (BWT)-type data decompression algorithm.

28. The method of claim 21 wherein said data file is not decompressed.

29. The method of claim 17 wherein said authentication information includes a time stamp representing the time at which authentication information was associated with said data file.

30. The method of claim 17 wherein said authentication information is based on a hash calculated for said data file.

31. The method of claim 17 wherein said authentication information is based on a cryptographic checksum.

32. The method of claim 17 wherein said authentication information is based on hash data that is asymmetrically decryptable using a public key.

33. The method of claim 17 wherein said data container is constructed in accordance with a .Zip file format.