Fujitsu Corporation

Souichi Okada

Masahiko Takenaka

Takayuki Hasebe

Naoya Torii

Takashi Yoshioka

Jun Kamada

Kouichi Itoh

Takehiko Hayashi

Bintatsu Noda

Satoru Watanabe

Jun Kakuta

Tomohiro Hayashi

Toshihiro Azami

Tsuneo Katsuyama

Chikahiro Deguchi

Yuji Kijima

Yumi Fujiwara

A common key block encryption apparatus for performing a nonlinear transformation with a multiplication executed in a binary field or a composite field includes a computing unit to execute a computation other than the nonlinear transformation with fixed value masked input data obtained by XORing input data with a fixed mask value, an XOR operation circuit to transform all input data into fixed value masked input data by XORing the input data with a fixed mask value and to transform the data into random value masked input data by XORing the input data with a random mask value in the multiplication, a multiplier to execute a multiplication based on the random value masked input data output from the XOR operation circuit, and a random value mask-to-fixed mask value transformation circuit to again transform the random value masked output data into fixed value masked output data and to output the data.

Encryption apparatus having common key encryption function and embedded apparatus

The first route selection device re-arrays a plurality of extended key mask values at random according to the value of a random number generated by a random number generation device. An extended key operation device generates an exclusive logical OR of a plurality of the re-arrayed extended key mask values, a data string representing extended key and an input data string. The second route selection device re-arrays the data string of the exclusive logical OR by performing a re-array conversely with the first route selection device according to the value of the random number. A non-linear conversion device applies non-linear conversion to the re-arrayed data string and outputs a data string masked by a plurality of non-linear conversion mask values. The third route selection device re-arrays the masked data string by performing the same re-array as the first route selection device according to the value of the random number.

Encrypting apparatus for common key cipher

A first access policy is stored to provide information on a first distributee to which an electronic document is distributed, to which the first distributee is permitted to distribute the electronic document, and use rights that permit the second distributees to use the electronic document. Also stored is a distribution target information indicating the second distributees. When the first distributee requests permission to grant use rights to a specific distributee, the distribution target is consulted to confirm whether or not the specific distributee is included in the second distributees. A second access policy associating the specific distributee with the information on the use rights is then registered. When the specific distributee requests permission to use the electronic document, the second access policy is consulted to permit the specific distributee to use the electronic document.

Computer-readable recording medium storing access rights management program, access rights management apparatus, and access rights management method

A computer program, apparatus, and method for managing access to documents, capable of identifying the exact events of document access on the basis of given access logs even when access policies are modified in the middle of operations. Upon receipt of an access policy setup request from a first client, an access policy manager adds a new access policy to the access policy database or modifies an existing access policy in an access policy database according to the request. A policy log collector then stores the records of such a new access policy or modified existing access policy in a policy log database. Afterwards an access log collector receives an access log for the documentfrom the second clientand saves it in the access log database. When a third client issues a log request with a specific search keyword, a log searcher retrieves relevant policy log records and access log records that match with the specified search keyword.

Method, apparatus, and computer program for managing access to documents

A memory management unit manages a memory that stores a code, and sets that the memory that stores the code to be executed is valid to make a processor execute the code stores a verification key used to verify a validity of the code in a verification-key storing unit. When the code is stored in the memory and ready to be executed by the processor, the memory management unit verifies the validity of the code using the verification key stored in the verification-key storing unit and verification information assigned to the code. The memory management unit controls to set that the memory is valid when the validity is verified by the verifying unit, and not to set that the memory is valid when the validity is not verified by the verifying unit.

Memory management unit, code verifying apparatus, and code decrypting apparatus

An encryption circuit that reduces a scale of circuit and can achieve a certain level of high-speed processing in the implementation of the AES block cipher. A round processing unit comprises: a first Round Key Addition circuit that adds a round key value to input data; an intermediate register/Shift Row transformation circuit that temporarily stores the output of the first Round Key Addition circuit and executes Shift Row transformation; a Byte Sub transformation circuit into which the values of the intermediate register/Shift Row transformation circuit are inputted and which executes Byte Sub transformation; a second Round Key Addition circuit into which the values of the intermediate register/Shift Row transformation circuit are inputted and which adds round key values; a Mix Column transformation circuit that executes Mix Column transformation upon the outputs of the second Round Key Addition circuit; and a second selector that outputs to the second Round Key Addition circuit one of the outputs of a first selector, the intermediate register/Shift Row transformation circuit, the Byte Sub transformation circuit, and the Mix Column transformation circuit.

Encryption circuit

A personal identification terminal includes a plurality of identification means or a plurality of identification levels that are selectable for use, and means for selecting one of the plural identification means or one of the identification levels in accordance with identification means/level setting information that is received from a server every time when receiving a request for identification from the server. The personal identification terminal sends used means/level information that indicates one of the identification means or one of the identification levels that was used for the real identification back to the server in a format that enables detection of an alteration thereof together with a result of the identification.

Personal identification terminal and method having selectable identification means or identification levels

When a user works data required for allowance for the use thereof, the work processing is carried out by utilizing an exclusive work processing device. Thereafter, only the data of work information indicating what kind of working has been made to the original data (for example, differential static image data indicating a difference between the original static image required for allowance for the use and the static image after having been worked) is stored, whereby the use without permission of the data is prevented.

Data protection system, data preparation device, and data working device

An electronic conference support system having a structure in which one main common information processing apparatus having a common display unit having a size sufficiently large for attendants to commonly look and some personal information processing apparatuses for permitting each attendant to exclusively create, display and edit information adjacent to each attendant are connected to one another to form a network communication structure through a data communication passage. When a certain attendant acquires an operation right, an information input space is displayed on the personal display unit of the attendant while permitting the attendant to input information. Information inputted to the information input space is, after completed and as an information object, displayed on the common display unit of the common information processing apparatus and the personal display units of all of the personal information processing apparatuses. The attendant of the conference is enabled to easily input information and other attendants who look the attendant's operation are enabled to be free from adverse stimulus.

Growing community of inventors

Kawasaki, Japan

Souichi Okada