Method and system for asymmetrically decrypting .ZIP files

• US 20050086474A1
• Filed: 09/20/2004
• Published: 04/21/2005
• 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:
  US10/945,475
• Publication Number:
  US 20050086474A1
• Time in Patent Office: Days
• US Class Current: 713/170
• 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

1-24. -24. (canceled)

25. A method of providing access to data in a .Zip file format data container, said method including:

receiving a data container including encrypted data; and

decrypting said encrypted data to form decrypted data, wherein said decryption includes decrypting said encrypted data using asymmetric decryption,

wherein said data container is constructed in accordance with a .Zip file format.

26. The method of claim 25 wherein said decrypted data is a decrypted data file.

27. The method of claim 26 further including providing access to said decrypted data file.

28. The method of claim 26 further including decompressing said decrypted data file.

29. The method of claim 28 wherein said decompressing employs a Lempel-Ziv (LZ)-type data decompression algorithm.

30. The method of claim 28 wherein said decompressing employs a Deflate-type data decompression algorithm.

31. The method of claim 28 wherein said decompressing employs a Burrows-Wheeler Transform (BWT)-type data decompression algorithm.

32. The method of claim 26 wherein said decrypted data file is not decompressed.

33. The method of claim 26 further including receiving decrypting data from an external input source.

34. The method of claim 33 further including using said decrypting data to decrypt said encrypted data.

35. The method of claim 25 wherein said asymmetric decryption employs a private key.

36. The method of claim 25 wherein said asymmetric decryption employs a X.509 digital certificate.

37. A method of providing access to data in a data container, said method including:

receiving a data container including encrypted data; and

decrypting said encrypted data to form decrypted data, wherein said decryption includes decrypting said encrypted data using asymmetric decryption,

wherein said data container is designed for containing compressed files.

38. The method of claim 37 wherein said decrypted data is a decrypted data file.

39. The method of claim 38 further including providing access to said decrypted data file.

40. The method of claim 38 further including decompressing said decrypted data file.

41. The method of claim 40 wherein said decompressing employs a Lempel-Ziv (LZ)-type data decompression algorithm.

42. The method of claim 40 wherein said decompressing employs a Deflate-type data decompression algorithm.

43. The method of claim 40 wherein said decompressing employs a Burrows-Wheeler Transform (BWT)-type data decompression algorithm.

44. The method of claim 38 wherein said decrypted data file is not decompressed.

45. The method of claim 37 further including receiving decrypting data from an external input source.

46. The method of claim 45 further including using said decrypting data to decrypt said encrypted data.

47. The method of claim 37 wherein said asymmetric decryption employs a private key.

48. The method of claim 37 wherein said asymmetric decryption employs a X.509 digital certificate.

49. The method of claim 41 wherein said data container is constructed in accordance with a .Zip file format.