File encrypting apparatus, file decrypting apparatus, system and program
AssigneeFinalCode, Inc.
InventorsToshio DOGU, Noriyuki TAKAHASHI, Takuya MATSUMOTO
Life of this patent
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Abstract
A file encrypting apparatus includes: an encryption key acquiring unit that acquires one or more encryption keys determined for respective ones of one or more users permitted to access an electronic file; a file encrypting unit that encrypts the electronic file; a supplementary information encrypting unit that encrypts, by using the one or more encryption keys, supplementary information including a file decryption key required for decryption of the encrypted electronic file; and an output unit that outputs the encrypted supplementary information in association with the encrypted electronic file.
Claims18
A file encrypting apparatus comprising:
- an encryption key acquiring unit that acquires one or more encryption keys determined for respective ones of one or more users permitted to access an electronic file;
- a file encrypting unit that encrypts the electronic file;
- a supplementary information encrypting unit that encrypts, by using the one or more encryption keys, supplementary information including a file decryption key required for decryption of the encrypted electronic file;
- and
- an output unit that outputs the encrypted supplementary information in association with the encrypted electronic file.
A file decrypting apparatus that decrypts an encrypted electronic file in which:
- encrypted supplementary information including a file decryption key required for decryption of an encrypted electronic file;
- and user identification information identifying respective ones of one or more users permitted to access the electronic file are associated with each other, the file decrypting apparatus comprising:
- a supplementary information decrypting unit that decrypts the encrypted supplementary information using a supplementary information decryption key predetermined for a user of the file decrypting apparatus if user identification information of the user of the file decrypting apparatus is associated with the electronic file;
- and
- a file decrypting unit that decrypts the encrypted electronic file using the file decryption key included in the supplementary information if the user identification information of the user of the file decrypting apparatus is associated with the electronic file.
Dependencies are inferred from the claim text.