Method and system for multiple asymmetric decryption of .ZIP files

• US 20050091489A1
• Filed: 09/20/2004
• Published: 04/28/2005
• 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:
  US10/946,250
• Publication Number:
  US 20050091489A1
• Time in Patent Office: Days
• US Class Current: 713/165
• 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 providing access to data 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 first set of encrypted data and a second set of encrypted data;

decrypting at least one of said first set of encrypted data and said second set of encrypted data to form decrypted data, wherein said decrypting includes decrypting said encrypted data using asymmetric decryption; and

providing access to said decrypted data.

2. The method of claim 1 wherein said first set of encrypted data is associated with a first data file included in said data container and said second set of encrypted data is associated with a second data file included in said data container.

3. The method of claim 1 wherein both said first set of encrypted data and said second set of encrypted data are associated with a single data file included in said data container.

4. The method of claim 1 wherein said first set of encrypted data includes first asymmetric key data and said second set of encrypted data includes second asymmetric key data.

5. The method of claim 3 wherein said first set of encrypted data includes first asymmetric key data and said second set of encrypted data includes a data file.

6. The method of claim 4 wherein said first asymmetric key data is not identical to said second asymmetric key data.

7. The method of claim 5 wherein at least one of said first asymmetric key data and said second asymmetric key data is used to decrypt said data file.

8. The method of claim 1 wherein at least one of said first asymmetric key data and said second asymmetric key data are derived from a symmetric key used to decrypt a data file.

9. The method of claim 8 wherein said symmetric key has a key length of at least 128 bits.

10. The method of claim 8 wherein said symmetric key has a key length of at least 192 bits.

11. The method of claim 8 wherein said symmetric key has a key length of at least 256 bits.

12. The method of claim 8 wherein said symmetric key is symmetrically decrypted using an AES decryption decoding.

13. The method of claim 8 wherein said symmetric key is symmetrically decrypted using a 3DES decryption decoding.

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

15. The method of claim 14 wherein said data file is decompressed using a Lempel-Ziv (LZ)-type data decompression algorithm.

16. The method of claim 14 wherein said data file is decompressed using a Deflate-type data decompression algorithm.

17. The method of claim 14 wherein said data file is decompressed using a Burrows-Wheeler Transform (BWT)-type data decompression algorithm.

18. The method of claim 8 wherein said data file is not decompressed.

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

receiving a data container including first asymmetric key data, second asymmetric key data, and an encrypted data file,

wherein both said first asymmetric key data and said second asymmetric key data are associated with said encrypted data file,

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

receiving decryption key input;

combining said decryption key input with one of said first asymmetric key data and said second asymmetric key data to form a decryption key when said decryption key input matches an input expected by one of said first asymmetric key data and said second asymmetric key data; and

decrypting said encrypted data file using said decryption key to provide access to said data file.

20. The method of claim 19 wherein said first asymmetric key data is not identical to said second asymmetric key data.

21. The method of claim 19 further including using said decryption key input in decrypting said asymmetric key data to provide an input into a decryption operation to decrypt said encrypted data file.

22. The method of claim 19 wherein said decryption key input is a private key.

23. The method of claim 19 wherein at least one of said first asymmetric key data and said second asymmetric key data are derived from a symmetric key used to decrypt said encrypted data file.

24. The method of claim 23 wherein said symmetric key has a key length of at least 128 bits.

25. The method of claim 23 wherein said symmetric key has a key length of at least 192 bits.

26. The method of claim 23 wherein said symmetric key has a key length of at least 256 bits.

27. The method of claim 23 wherein said symmetric key is symmetrically decrypted using an AES decryption decoding.

28. The method of claim 23 wherein said symmetric key is symmetrically decrypted using a 3DES decryption decoding.

29. The method of claim 23 further including decompressing said encrypted data file after decrypting said data file.

30. The method of claim 29 wherein said data file is decompressed using a Lempel-Ziv (LZ)-type data decompression algorithm.

31. The method of claim 29 wherein said data file is decompressed using a Deflate-type data decompression algorithm.

32. The method of claim 29 wherein said data file is decompressed using a Burrows-Wheeler Transform (BWT)-type data decompression algorithm.

33. The method of claim 23 wherein said data file is not decompressed.

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

receiving a data container including;

first asymmetric key data;

second asymmetric key data; and

an encrypted data file,

wherein said first asymmetric key data is derived from an asymmetric encryption, using a first asymmetric key, of symmetric key data formed from a symmetric key used to encrypt said encrypted data file,

wherein said second asymmetric key data is derived from an asymmetric encryption, using a second asymmetric key, of said symmetric key data formed from said symmetric key used to encrypt said encrypted data file

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

providing the option of;

using said first asymmetric key data to recover said symmetric key to decrypt said encrypted data file when a first desired input is received; and

using said second asymmetric key data to recover said symmetric key to decrypt said encrypted data file when a second desired input is received.

35. The method of claim 34 wherein said decryption key input is a private key.

36. The method of claim 34 wherein said first asymmetric key data is not identical to said second asymmetric key data.

37. The method of claim 34 wherein said symmetric key has a key length of at least 128 bits.

38. The method of claim 34 wherein said symmetric key has a key length of at least 192 bits.

39. The method of claim 34 wherein said symmetric key has a key length of at least 256 bits.

40. The method of claim 34 wherein said symmetric key is symmetrically decrypted using an AES decryption decoding.

41. The method of claim 34 wherein said symmetric key is symmetrically decrypted using a 3DES decryption decoding.

42. The method of claim 34 further including decompressing said data file after said data file is decrypted.

43. The method of claim 42 wherein said data file is decompressed using a Lempel-Ziv (LZ)-type data decompression algorithm.

44. The method of claim 42 wherein said data file is decompressed using a Deflate-type data decompression algorithm.

45. The method of claim 42 wherein said data file is decompressed using a Burrows-Wheeler Transform (BWT)-type data decompression algorithm.

46. The method of claim 34 wherein said data file is not decompressed.

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

receiving a data container designed for containing compressed files, said data container including a first set of encrypted data and a second set of encrypted data;

decrypting at least one of said first set of encrypted data and said second set of encrypted data to form decrypted data, wherein said decrypting includes decrypting said encrypted data using asymmetric decryption; and

providing access to said decrypted data.

48. The method of claim 47 wherein said first set of encrypted data is associated with a first data file included in said data container and said second set of encrypted data is associated with a second data file included in said data container.

49. The method of claim 47 wherein both said first set of encrypted data and said second set of encrypted data are associated with a single data file included in said data container.

50. The method of claim 47 wherein said first set of encrypted data includes first asymmetric key data and said second set of encrypted data includes second asymmetric key data.

51. The method of claim 49 wherein said first set of encrypted data includes first asymmetric key data and said second set of encrypted data includes a data file.

52. The method of claim 50 wherein said first asymmetric key data is not identical to said second asymmetric key data.

53. The method of claim 51 wherein at least one of said first asymmetric key data and said second asymmetric key data is used to decrypt said data file.

54. The method of claim 47 wherein at least one of said first asymmetric key data and said second asymmetric key data are derived from a symmetric key used to decrypt a data file.

55. The method of claim 54 wherein said symmetric key has a key length of at least 128 bits.

56. The method of claim 54 wherein said symmetric key has a key length of at least 192 bits.

57. The method of claim 54 wherein said symmetric key has a key length of at least 256 bits.

58. The method of claim 54 wherein said symmetric key is symmetrically decrypted using an AES decryption decoding.

59. The method of claim 54 wherein said symmetric key is symmetrically decrypted using a 3DES decryption decoding.

60. The method of claim 54 further including decompressing said data file after decrypting said data file.

61. The method of claim 60 wherein said data file is decompressed using a Lempel-Ziv (LZ)-type data decompression algorithm.

62. The method of claim 60 wherein said data file is decompressed using a Deflate-type data decompression algorithm.

63. The method of claim 60 wherein said data file is decompressed using a Burrows-Wheeler Transform (BWT)-type data decompression algorithm.

64. The method of claim 54 wherein said data file is not decompressed.

65. The method of claim 47 wherein said data container is constructed in accordance with a .Zip file format.

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

receiving a data container including first asymmetric key data, second asymmetric key data, and an encrypted data file,

wherein both said first asymmetric key data and said second asymmetric key data are associated with said encrypted data file,

wherein said data container is designed for containing compressed files; and

receiving decryption key input;

combining said decryption key input with one of said first asymmetric key data and said second asymmetric key data to form a decryption key when said decryption key input matches an input expected by one of said first asymmetric key data and said second asymmetric key data; and

decrypting said encrypted data file using said decryption key to provide access to said data file.

67. The method of claim 66 wherein said first asymmetric key data is not identical to said second asymmetric key data.

68. The method of claim 66 further including using said decryption key input in decrypting said asymmetric key data to provide an input into a decryption operation to decrypt said encrypted data file.

69. The method of claim 66 wherein said decryption key input is a private key.

70. The method of claim 66 wherein at least one of said first asymmetric key data and said second asymmetric key data are derived from a symmetric key used to decrypt said encrypted data file.

71. The method of claim 70 wherein said symmetric key has a key length of at least 128 bits.

72. The method of claim 70 wherein said symmetric key has a key length of at least 192 bits.

73. The method of claim 70 wherein said symmetric key has a key length of at least 256 bits.

74. The method of claim 70 wherein said symmetric key is symmetrically decrypted using an AES decryption decoding.

75. The method of claim 70 wherein said symmetric key is symmetrically decrypted using a 3DES decryption decoding.

76. The method of claim 70 further including decompressing said encrypted data file after decrypting said data file.

77. The method of claim 76 wherein said data file is decompressed using a Lempel-Ziv (LZ)-type data decompression algorithm.

78. The method of claim 76 wherein said data file is decompressed using a Deflate-type data decompression algorithm.

79. The method of claim 76 wherein said data file is decompressed using a Burrows-Wheeler Transform (BWT)-type data decompression algorithm.

80. The method of claim 70 wherein said data file is not decompressed.

81. The method of claim 66 wherein said data container is constructed in accordance with a .Zip file format.

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

receiving a data container including;

first asymmetric key data;

second asymmetric key data; and

an encrypted data file,

wherein said first asymmetric key data is derived from an asymmetric encryption, using a first asymmetric key, of symmetric key data formed from a symmetric key used to encrypt said encrypted data file,

wherein said second asymmetric key data is derived from an asymmetric encryption, using a second asymmetric key, of said symmetric key data formed from said symmetric key used to encrypt said encrypted data file

wherein said data container is designed for containing compressed files; and

providing the option of;

using said first asymmetric key data to recover said symmetric key to decrypt said encrypted data file when a first desired input is received; and

using said second asymmetric key data to recover said symmetric key to decrypt said encrypted data file when a second desired input is received.

83. The method of claim 82 wherein said decryption key input is a private key.

84. The method of claim 82 wherein said first asymmetric key data is not identical to said second asymmetric key data.

85. The method of claim 82 wherein said symmetric key has a key length of at least 128 bits.

86. The method of claim 82 wherein said symmetric key has a key length of at least 192 bits.

87. The method of claim 82 wherein said symmetric key has a key length of at least 256 bits.

88. The method of claim 82 wherein said symmetric key is symmetrically decrypted using an AES decryption decoding.

89. The method of claim 82 wherein said symmetric key is symmetrically decrypted using a 3DES decryption decoding.

90. The method of claim 82 further including decompressing said data file after said data file is decrypted.

91. The method of claim 90 wherein said data file is decompressed using a Lempel-Ziv (LZ)-type data decompression algorithm.

92. The method of claim 90 wherein said data file is decompressed using a Deflate-type data decompression algorithm.

93. The method of claim 90 wherein said data file is decompressed using a Burrows-Wheeler Transform (BWT)-type data decompression algorithm.

94. The method of claim 82 wherein said data file is not decompressed.

95. The method of claim 82 wherein said data container is constructed in accordance with a .Zip file format.