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    21.
    发明专利
    未知

    公开(公告)号：DE69328334T2

    公开(公告)日：2000-10-19

    申请号：DE69328334

    申请日：1993-09-08

    Applicant: IBM

    Inventor： ELANDER ROBERT C ,  HOLLOWAY CHRISTOPHER J ,  JOHNSON DONALD B ,  KELLY MICHAEL J ,  LE AN V ,  LUBOLD PAUL G ,  MATYAS STEPHEN M ,  RANDALL JAMES D ,  WILKINS JOHN D

    IPC: G09C1/00 ,  H04L9/06 ,  H04L9/08

    Abstract: A method and system are disclosed for the implementation of a weakened privacy channel. This is achieved through use of a weakened symmetric cryptographic algorithm called commercial data masking. The masked text is created from clear text at one system and may to transported electronically to another system where the masked text may be unmasked to produce the clear text. The reason to use the commercial data masking algorithm for data privacy is that it is exportable to organizations to which products which contain the Data Encryption Algorithm when used for data privacy are not exportable. In addition, a method and system is disclosed by which the key when used for commercial data masking may be transformed into a key that may be used with the Data Encryption Algorithm.

    CRYPTOGRAPHIC KEY RECOVERY SYSTEM
    23.
    发明专利
    CRYPTOGRAPHIC KEY RECOVERY SYSTEM 未知

    公开(公告)号：CA2197915A1

    公开(公告)日：1997-10-11

    申请号：CA2197915

    申请日：1997-02-05

    Applicant: IBM

    Inventor： JOHNSON DONALD B ,  KARGER PAUL A ,  KAUFMAN CHARLES W JR ,  MATYAS STEPHEN M JR ,  YUNG MARCEL M ,  ZUNIC NEVENKO

    IPC: H04L9/08 ,  H04L9/10 ,  H04L9/14

    Abstract: A cryptographic key recovery system for generating a cryptographic key for use by a pair of communicating parties while simultaneously providing for its recovery using one or more key recover agents. A plurality of m-bit shared key parts (P, Q) are generated which are shared with respective key recovery agents, while an n-bit nonshared key part (R) is generated that is not shared with any key recovery agent. The shared key parts (P, Q) are combined to generate an m-bit value which is concatenated with the nonshared key part (R) to generate an (m + n)-bit value from which an encryption key is generated. The cryptographic system has the effective work factor of an n-bit key to all of the key recovery agents acting in concert, but has the effective work factor of an (m + n)-bit to any other combination of third parties. The quantity n is selected to make authorized key recovery feasible, but not so trivial as to permit routine decryption of intercepted communications, while the quantity m is selected to make decryption by unauthorized third parties infeasible. Means are provided for verifying that the shared key parts have been shared with the key recovery agents before permitting encrypted communications using the thus generated key.

    24.
    发明专利
    未知

    公开(公告)号：DE69217428D1

    公开(公告)日：1997-03-27

    申请号：DE69217428

    申请日：1992-07-10

    Applicant: IBM

    Inventor： MATYAS STEPHEN M ,  JOHNSON DONALD B ,  LE AN V ,  MARTIN WILLIAM C ,  PRYMAK ROSTISLAW ,  ROHLAND WILLIAM S ,  WILKINS JOHN D

    IPC: G06F21/20 ,  G06F9/30 ,  G09C1/00 ,  H04L9/08

    Abstract: The patent describes a method and apparatus for securely distributing an initial Data Encryption Algorithm (DEA) key-encrypting key by encrypting a key record (consisting of the key-encrypting key and control information associated with that key-encrypting key) using a public key algorithm and a public key belonging to the intended recipient of the key record. The patent further describes a method and apparatus for securely recovering the distributed key-encrypting key by the recipient by decrypting the received key record using the same public key algorithm and private key associated with the public key and re-encrypting the key-encrypting key under a key formed by arithmetically combining the recipient's master key with a control vector contained in the control information of the received key record. Thus the type and usage attributes assigned by the originator of the key-encrypting key in the form of a control vector are cryptographically coupled to the key-encrypting key such that the recipient may only use the received key-encrypting key in a manner defined by the key originator. The patent further describes a method and apparatus to improve the integrity of the key distribution process by applying a digital signature to the key record and by including identifying information (i.e., an originator identifier) in the control information of the key record. The integrity of the distribution process is enhanced by verifying the digital signature and originator identifier at the recipient node.

    DATA CRYPTOGRAPHY OPERATIONS USING CONTROL VECTORS
    29.
    发明专利
    DATA CRYPTOGRAPHY OPERATIONS USING CONTROL VECTORS 未知

    公开(公告)号：CA1322418C

    公开(公告)日：1993-09-21

    申请号：CA602905

    申请日：1989-06-15

    Applicant: IBM

    Inventor： MATYAS STEPHEN M ,  ABRAHAM DENNIS G ,  JOHNSON DONALD B ,  KARNE RAMESH K ,  LE AN V ,  PRYMAK ROSTISLAW ,  THOMAS JULIAN ,  WILKINS JOHN D ,  YEH PHIL C

    IPC: G09C1/00 ,  H04L9/00 ,  H04L9/08 ,  H04L9/10 ,  H04L9/32

    Abstract: MA9-88-012 DATA CRYPTOGRAPHY OPERATIONS USING CONTROL VECTORS Data cryptography is achieved in an improved manner by associating with the data cryptography key, a control vector which provides the authorization for the uses of the key intended by the originator of the key. Among the uses specified by the control vector are limitations on encryption, decryption, authentication code generation and verification, translation of the user's data. Complex combinations of data manipulation functions are possible using the control vectors, in accordance with the invention. The system administrator can exercise flexibility in changing the implementation of his security policy by selecting appropriate control vectors in accordance with the invention. Complex scenarios such as encrypted mail box, session protection, file protection, ciphertext translation center, peer-to-peer ciphertext translation, message authentication, message authentication with non-repudiation and many others can be easily implemented by a system designer using the control vectors, in accordance with the invention.

    SECURE MANAGEMENT OF KEYS USING EXTENDED CONTROL VECTORS
    30.
    发明专利
    SECURE MANAGEMENT OF KEYS USING EXTENDED CONTROL VECTORS 未知

    公开(公告)号：CA1319198C

    公开(公告)日：1993-06-15

    申请号：CA600674

    申请日：1989-05-25

    Applicant: IBM

    Inventor： MATYAS STEPHEN M ,  ABRAHAM DENNIS G ,  ARNOLD WILLIAM C ,  JOHNSON DONALD B ,  KARNE RAMESH K ,  LE AN V ,  PRYMAK ROSTISLAW ,  WHITE STEVE R ,  WILKINS JOHN D

    IPC: G09C1/00 ,  H04L9/08

    Abstract: MA9-88-023 SECURE MANAGEMENT OF KEYS USING EXTENDED CONTROL VECTORS A method and apparatus are disclosed for use in a data processing system which executes a program which outputs cryptographic service requests for operations with cryptographic keys which are associated with control vectors defining the functions which each key is allowed by its originator to perform. The improved method and apparatus enable the use of control vectors having an arbitrary length. It includes a control vector register having an arbitrary length, for storing a control vector of arbitrary length associated with an N-bit cryptographic key. It further includes a control vector checking means having an input coupled to the control vector register, for checking that the control vector authorizes the cryptographic function which is requested by the cryptographic service request. It further includes a hash function generator having an input coupled to the control vector register and an N-bit output, for mapping the control vector output from the control vector register, into an N-bit hash value. A key register is included for storing the N-bit cryptographic key. It further includes a logic block having a first input coupled to the N-bit output of the hash function generator, and a second input connected to the key register, for forming at the output thereof a product of the N-bit key and the N-bit hash value. Finally, an encryption device is included having a first input for receiving a cleartext data stream and a key input coupled to the output of the logic block, for forming a ciphertext data stream at the output thereof from the cleartext data stream and the product. A decryption device can be substituted for the encryption device to perform decryption operations in a similar manner.

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