Method and system for encryption of file characteristics of .ZIP files

• US 20090144562A9
• Filed: 09/20/2004
• Published: 06/04/2009
• Est. Priority Date: 03/09/2000
• Status: Active Grant

• Current Assignee: PKWARE, Inc. (PKW Holdings, Inc.)
• Original Assignee: PKWARE, Inc. (PKW Holdings, Inc.)
• Inventors: Peterson, James
• Granted Patent: US 7,793,099 B2
• Time in Patent Office: Days
• US Class Current: 713/193
• 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 protecting at least one file characteristic of a data file in a .Zip file format data container, said method including:

receiving a data file;

receiving at least one file characteristic associated with said data file;

encrypting said at least one file characteristic; and

placing said at least one file characteristic in a data container, wherein said data container is constructed in accordance with a .Zip file format.

2. The method of claim 1 further including placing said data file in said data container.

3. The method of claim 1 wherein said at least one file characteristic is symmetrically encrypted using a symmetric key.

4. The method of claim 3 wherein at least part of said symmetric key is composed of random data.

5. The method of claim 3 wherein at least part of said symmetric key is input by a user

6. The method of claim 5 wherein said at least part of said symmetric key is a password.

7. The method of claim 3 wherein said symmetric key has a key length of at least 128 bits.

8. The method of claim 3 wherein said symmetric key has a key length of at least 192 bits.

9. The method of claim 3 wherein said symmetric key has a key length of at least 256 bits.

10. The method of claim 3 wherein said at least one file characteristic is symmetrically encrypted using an AES encryption encoding.

11. The method of claim 3 wherein said at least one file characteristic is symmetrically encrypted using a 3DES encryption encoding.

12. The method of claim 1 wherein said at least one file characteristic is asymmetrically encrypted.

13. The method of claim 12 wherein said asymmetric encryption employs a public key.

14. The method of claim 12 wherein said asymmetric encryption employs a X.509 digital certificate.

15. The method of claim 1 including a plurality of file characteristics.

16. The method of claim 15 wherein not all of said plurality of file characteristics are encrypted.

17. The method of claim 15 wherein at least one of said plurality of file characteristics is encrypted using a first type of encryption and at least one of said plurality of file characteristics is encrypted using a second type of encryption.

18. The method of claim 17 wherein a first of said plurality of file characteristics is encrypted using a first symmetric encryption and a second of said plurality of file characteristics is encrypted using a second symmetric encryption different from said first symmetric encryption.

19. The method of claim 18 wherein said first symmetric encryption employs a key having a first key length and said second symmetric encryption employs a key having a second key length different from said first key length.

20. The method of claim 17 wherein a first of said plurality of file characteristics is encrypted using a first asymmetric encryption and a second of said plurality of file characteristics is encrypted using a second asymmetric encryption different from said first asymmetric encryption.

21. The method of claim 1 wherein said at least one file characteristic includes the name of said data file.

22. The method of claim 1 wherein said at least one file characteristic includes the size of said data file.

23. The method of claim 1 wherein said at least one file characteristic includes the creation date of said data file

24. The method of claim 1 wherein said at least one file characteristic includes the creation time of said data file.

25. The method of claim 2 wherein said data file is compressed before said data file is placed in the data container.

26. The method of claim 25 wherein said data file is encrypted after said data file is compressed and before said data file is placed in said data container using a symmetric encryption.

27. The method of claim 25 wherein said data file is encrypted after said data file is compressed and before said data file is placed in said data container using an asymmetric encryption.

28. The method of claim 25 wherein said data file has been compressed using a Lempel-Ziv (LZ)-type data compression algorithm.

29. The method of claim 25 wherein said data file has been compressed using a Deflate-type data compression algorithm.

30. The method of claim 25 wherein said data file has been compressed using a Burrows-Wheeler Transform (BWT)-type data compression algorithm.

31. The method of claim 2 wherein said data file is placed in the data container without compressing said data file.

32. The method of claim 2 wherein said data file is encrypted before said data file is placed in said data container.

33. The method of claim 25 wherein said data file is encrypted after said data file is compressed and before said data file is placed in said data container.

34. The method of claim 1 further including compressing said at least one file characteristic before encrypting said at least one file characteristic.

35. A .Zip file format data container including:

a data file; and

at least one file characteristic relating to said data file,

wherein at least one of said at least one file characteristic is encrypted,

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

36. The .Zip file format data container of claim 35 further including said data file.

37. The .Zip file format data container of claim 35 wherein said at least one file characteristic is symmetrically encrypted using a symmetric key.

38. The .Zip file format data container of claim 37 wherein at least part of said symmetric key is composed of random data.

39. The .Zip file format data container of claim 37 wherein at least part of said symmetric key is input by a user

40. The .Zip file format data container of claim 39 wherein said at least part of said symmetric key is a password.

41. The .Zip file format data container of claim 37 wherein said symmetric key has a key length of at least 128 bits.

42. The .Zip file format data container of claim 37 wherein said symmetric key has a key length of at least 192 bits.

43. The .Zip file format data container of claim 37 wherein said symmetric key has a key length of at least 256 bits.

44. The .Zip file format data container of claim 37 wherein said at least one file characteristic is symmetrically encrypted using an AES encryption encoding.

45. The .Zip file format data container of claim 37 wherein said at least one file characteristic is symmetrically encrypted using a 3DES encryption encoding.

46. The .Zip file format data container of claim 35 wherein said at least one file characteristic is asymmetrically encrypted.

47. The .Zip file format data container of claim 46 wherein said asymmetric encryption employs a public key.

48. The .Zip file format data container of claim 46 wherein said asymmetric encryption employs a X.509 digital certificate.

49. The .Zip file format data container of claim 35 including a plurality of file characteristics.

50. The .Zip file format data container of claim 49 wherein not all of said plurality of file characteristics are encrypted.

51. The .Zip file format data container of claim 49 wherein at least one of said plurality of file characteristics is encrypted using a first type of encryption and at least one of said plurality of file characteristics is encrypted using a second type of encryption.

52. The .Zip file format data container of claim 51 wherein a first of said plurality of file characteristics is encrypted using a first symmetric encryption and a second of said plurality of file characteristics is encrypted using a second symmetric encryption different from said first symmetric encryption.

53. The .Zip file format data container of claim 52 wherein said first symmetric encryption employs a key having a first key length and said second symmetric encryption employs a key having a second key length different from said first key length.

54. The .Zip file format data container of claim 49 wherein a first of said plurality of file characteristics is encrypted using a first asymmetric encryption and a second of said plurality of file characteristics is encrypted using a second asymmetric encryption different from said first asymmetric encryption.

55. The .Zip file format data container of claim 35 wherein said at least one file characteristic includes the name of said data file.

56. The .Zip file format data container of claim 35 wherein said at least one file characteristic includes the size of said data file.

57. The .Zip file format data container of claim 35 wherein said at least one file characteristic includes the creation date of said data file

58. The .Zip file format data container of claim 35 wherein said at least one file characteristic includes the creation time of said data file.

59. The .Zip file format data container of claim 36 wherein said data file is compressed before said data file is placed in the data container.

60. The .Zip file format data container of claim 59 wherein said data file is encrypted after said data file is compressed and before said data file is placed in said data container using a symmetric encryption.

61. The .Zip file format data container of claim 59 wherein said data file is encrypted after said data file is compressed and before said data file is placed in said data container using an asymmetric encryption.

62. The .Zip file format data container of claim 59 wherein said data file has been compressed using a Lempel-Ziv (LZ)-type data compression algorithm.

63. The .Zip file format data container of claim 59 wherein said data file has been compressed using a Deflate-type data compression algorithm.

64. The .Zip file format data container of claim 59 wherein said data file has been compressed using a Burrows-Wheeler Transform (BWT)-type data compression algorithm.

65. The .Zip file format data container of claim 36 wherein said data file is placed in the data container without compressing said data file.

66. The .Zip file format data container of claim 36 wherein said at least one file characteristic is compressed before said at least one file characteristic is encrypted.

67. The .Zip file format data container of claim 59 wherein said data file is encrypted after said data file is compressed and before said data file is placed in said data container.

68. The .Zip file format data container of claim 35 wherein said at least one file characteristics is compressed before said at least one file characteristic is encrypted.

69. A method of protecting at least one file characteristic of a data file, said method including:

receiving a data file;

receiving at least one file characteristic associated with said data file;

encrypting said at least one file characteristic; and

placing said at least one file characteristic in a data container designed for compressed files.

70. The method of claim 69 further including placing said data file in said data container.

71. The method of claim 69 wherein said at least one file characteristic is symmetrically encrypted using a symmetric key.

72. The method of claim 71 wherein at least part of said symmetric key is composed of random data.

73. The method of claim 71 wherein at least part of said symmetric key is input by a user

74. The method of claim 73 wherein said at least part of said symmetric key is a password.

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

76. The method of claim 71 wherein said symmetric key has a key length of at least 192 bits.

77. The method of claim 71 wherein said symmetric key has a key length of at least 256 bits.

78. The method of claim 71 wherein said at least one file characteristic is symmetrically encrypted using an AES encryption encoding.

79. The method of claim 71 wherein said at least one file characteristic is symmetrically encrypted using a 3DES encryption encoding.

80. The method of claim 69 wherein said at least one file characteristic is asymmetrically encrypted.

81. The method of claim 80 wherein said asymmetric encryption employs a public key.

82. The method of claim 80 wherein said asymmetric encryption employs a X.509 digital certificate.

83. The method of claim 69 including a plurality of file characteristics.

84. The method of claim 83 wherein not all of said plurality of file characteristics are encrypted.

85. The method of claim 83 wherein at least one of said plurality of file characteristics is encrypted using a first type of encryption and at least one of said plurality of file characteristics is encrypted using a second type of encryption.

86. The method of claim 85 wherein a first of said plurality of file characteristics is encrypted using a first symmetric encryption and a second of said plurality of file characteristics is encrypted using a second symmetric encryption different from said first symmetric encryption.

87. The method of claim 86 wherein said first symmetric encryption employs a key having a first key length and said second symmetric encryption employs a key having a second key length different from said first key length.

88. The method of claim 85 wherein a first of said plurality of file characteristics is encrypted using a first asymmetric encryption and a second of said plurality of file characteristics is encrypted using a second asymmetric encryption different from said first asymmetric encryption.

89. The method of claim 69 wherein said at least one file characteristic includes the name of said data file.

90. The method of claim 69 wherein said at least one file characteristic includes the size of said data file.

91. The method of claim 69 wherein said at least one file characteristic includes the creation date of said data file

92. The method of claim 69 wherein said at least one file characteristic includes the creation time of said data file.

93. The method of claim 70 wherein said data file is compressed before said data file is placed in the data container.

94. The method of claim 93 wherein said data file is encrypted after said data file is compressed and before said data file is placed in said data container using a symmetric encryption.

95. The method of claim 93 wherein said data file is encrypted after said data file is compressed and before said data file is placed in said data container using an asymmetric encryption.

96. The method of claim 93 wherein said data file has been compressed using a Lempel-Ziv (LZ)-type data compression algorithm.

97. The method of claim 93 wherein said data file has been compressed using a Deflate-type data compression algorithm.

98. The method of claim 93 wherein said data file has been compressed using a Burrows-Wheeler Transform (BWT)-type data compression algorithm.

99. The method of claim 70 wherein said data file is placed in the data container without compressing said data file.

100. The method of claim 70 wherein said data file is encrypted before said data file is placed in said data container.

101. The method of claim 93 wherein said data file is encrypted after said data file is compressed and before said data file is placed in said data container.

102. The method of claim 69 further including compressing said at least one file characteristic before encrypting said at least one file characteristic.

103. The method of claim 69 wherein said data container is constructed in accordance with a .Zip file format.

104. A data container including:

a data file; and

at least one file characteristic relating to said data file,

wherein at least one of said at least one file characteristic is encrypted,

wherein said data container is designed for containing compressed files

105. The data container of claim 104 further including said data file.

106. The data container of claim 104 wherein said at least one file characteristic is symmetrically encrypted using a symmetric key.

107. The data container of claim 106 wherein at least part of said symmetric key is composed of random data.

108. The data container of claim 106 wherein at least part of said symmetric key is input by a user

109. The data container of claim 108 wherein said at least part of said symmetric key is a password.

110. The data container of claim 106 wherein said symmetric key has a key length of at least 128 bits.

111. The data container of claim 106 wherein said symmetric key has a key length of at least 192 bits.

112. The data container of claim 106 wherein said symmetric key has a key length of at least 256 bits.

113. The data container of claim 106 wherein said at least one file characteristic is symmetrically encrypted using an AES encryption encoding.

114. The data container of claim 106 wherein said at least one file characteristic is symmetrically encrypted using a 3DES encryption encoding.

115. The data container of claim 104 wherein said at least one file characteristic is asymmetrically encrypted.

116. The data container of claim 115 wherein said asymmetric encryption employs a public key.

117. The data container of claim 115 wherein said asymmetric encryption employs a X.509 digital certificate.

118. The data container of claim 104 including a plurality of file characteristics.

119. The data container of claim 118 wherein not all of said plurality of file characteristics are encrypted.

120. The data container of claim 118 wherein at least one of said plurality of file characteristics is encrypted using a first type of encryption and at least one of said plurality of file characteristics is encrypted using a second type of encryption.

121. The data container of claim 120 wherein a first of said plurality of file characteristics is encrypted using a first symmetric encryption and a second of said plurality of file characteristics is encrypted using a second symmetric encryption different from said first symmetric encryption.

122. The data container of claim 121 wherein said first symmetric encryption employs a key having a first key length and said second symmetric encryption employs a key having a second key length different from said first key length.

123. The data container of claim 118 wherein a first of said plurality of file characteristics is encrypted using a first asymmetric encryption and a second of said plurality of file characteristics is encrypted using a second asymmetric encryption different from said first asymmetric encryption.

124. The data container of claim 104 wherein said at least one file characteristic includes the name of said data file.

125. The data container of claim 104 wherein said at least one file characteristic includes the size of said data file.

126. The data container of claim 104 wherein said at least one file characteristic includes the creation date of said data file

127. The data container of claim 104 wherein said at least one file characteristic includes the creation time of said data file.

128. The data container of claim 105 wherein said data file is compressed before said data file is placed in the data container.

129. The data container of claim 128 wherein said data file is encrypted after said data file is compressed and before said data file is placed in said data container using a symmetric encryption.

130. The data container of claim 128 wherein said data file is encrypted after said data file is compressed and before said data file is placed in said data container using an asymmetric encryption.

131. The data container of claim 128 wherein said data file has been compressed using a Lempel-Ziv (LZ)-type data compression algorithm.

132. The data container of claim 128 wherein said data file has been compressed using a Deflate-type data compression algorithm.

133. The data container of claim 128 wherein said data file has been compressed using a Burrows-Wheeler Transform (BWT)-type data compression algorithm.

134. The data container of claim 105 wherein said data file is placed in the data container without compressing said data file.

135. The data container of claim 105 wherein said at least one file characteristic is compressed before said at least one file characteristic is encrypted.

136. The data container of claim 128 wherein said data file is encrypted after said data file is compressed and before said data file is placed in said data container.

137. The data container of claim 104 wherein said at least one file characteristics is compressed before said at least one file characteristic is encrypted.

138. The data container of claim 104 wherein said data container is constructed in accordance with a .Zip file format.