Process for access control to computer-controlled programs usable by several user units at the same time

• US 6,199,101 B1
• Filed: 06/03/1998
• Issued: 03/06/2001
• Est. Priority Date: 12/22/1995
• Status: Expired due to Term

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Pfaff, Oliver
• Primary Examiner(s): Swann, Tod R.
• Assistant Examiner(s): GRECO, MICHAEL
• Application Number:
  US09/077,510
• Time in Patent Office: 1,007 Days
• Field of Search: 713/169, 713/171, 713/176, 713/168, 713/170, 380/285, 380/283, 380/30
• US Class Current: 709/204
• CPC Class Codes: G06F 9/468 Specific access rights for resources, e.g. using capability register

Abstract

A method for access control to computer-controlled programs, which can be used at the same time by a plurality of users. A user sends a request regarding a program to a unit for organizing a data flow. It is checked in this unit whether the user which sent the request, has originally started the program. When the user sending the request has started the program, the request is forwarded to the program. If not, an access control with respect to the request is carried out on the basis of an access control data bank. When it derives from the access control that the request is an allowed request, the request is forwarded to the program. When it derives from the access control that the request represents an unallowed request, the request is not forwarded to the program.

Claims

1. A method for access control to computer-controlled programs that can be simultaneously used by a plurality of user units, comprising the steps of:

sending a request for a program from a user unit;

receiving the request for the program in a data flow organization unit;

performing a check organization in the data flow organization unit to see whether the user unit from which the request was sent had originally started the program;

when the user unit sending the request had started the program, forwarding the request to the program;

when the user unit sending the request had not started the program, implementing an access control for the request on the basis of an access control data bank;

forwarding the request to the program when the access control shows that the request represents an allowed request; and

not forwarding the request to the program when the access control shows that the request represents an unallowed request.

2. The method according to claim 1, wherein before the check whether the user unit had originally started the program, performing a check in the organization unit to see whether the user unit possesses a processing right at the time of transmission of the request;

and

not forwarding the request to the program when the user unit had no processing right.

3. The method according to claim 1, wherein an authentification of the user unit that sent the request or of the request is implemented at a beginning of the method.

4. The method according to claim 3, wherein an initialization phase for the authentification is implemented given a connection setup between a user unit and the program.

5. Method according to claim 1 whereby the access control data bank comprises at least the following information:

a specification of the client to which the entry in the access control data bank refers;

a specification of the window to which the entry in the access control data bank refers;

the user unit;

a specification of a request type whose more detailed properties are specified in further parameters; and

further parameters that the request must comprise in order to be accepted as an allowed request.

6. A method for access control to computer-controlled programs that can be simultaneously used by a plurality of user units, comprising the steps of:

sending a request for a program from a user unit;

receiving the request for the program in a data flow organization unit and authenticating the user unit that sent the request;

implementing an initialization phase for the authentification given a connection setup between the user unit and the program;

providing the organization unit as a multiplexer component;

in the initialization phase, where the user unit has a user certificate and the multiplexer component has a program certificate, performing the following steps;

generating a first random number by the multiplexer component;

with the multiplexer component, sending a first negotiation message to the user unit, said negotiation message comprising at least the following components

a program certificate,

a first random number,

a first proposal, and

a digital signature that is formed at least over the first random number

and the first proposal;

receiving the first negotiation message by the user unit;

checking the program certificate by the user unit;

checking the digital signature by the user unit;

when the check of the program certificate and of the digital signature supplies a positive result, with the user unit checking whether proposed cryptographic algorithms can be subsequently employed;

when the cryptographic algorithms are not supported by the user unit with the user unit forming a second proposal in a second proposal message and sending the second proposal to the multiplexer component, said second proposal message comprising at least the following components;

the user certificate,

a second random number that is generated by the user unit,

a digital signature that is formed at least over the first random number,

the second random number and the further proposal;

when the cryptographic algorithms are supported, forming with the user unit an acknowledgment message and sending it to the multiplexer component, said acknowledgment message comprising at least the following components

a user certificate,

a second random number that is generated by the user unit,

a positive acknowledgment, and

a digital signature that is formed at least over the first random number, the second random number and the positive acknowledgment;

receiving the second negotiation message or the acknowledgment message by the multiplexer component;

checking with the multiplexer component the user certificate;

checking with the multiplexer component the digital signature;

when the check of the user certificate and of the digital signature supplies a positive result and the acknowledgment message was received, generating with the multiplexer component a first session key taking the declared cryptographic algorithms for a following useful data transmission phase into consideration;

when the check of the user certificate and of the digital signature supplies a positive result and the further negotiation message was received, checking with the multiplexer component whether the proposed cryptographic algorithms can be subsequently employed;

when the proposed cryptographic algorithms can be subsequently employed, generating with the multiplexer component a first session key taking the declared cryptographic algorithms for a following useful data transmission phase into consideration;

sending with the multiplexer component a first session key message to the user unit, said first session key message comprising at least the following components;

the first session key encrypted with a public key of the user unit, and

a digital signature formed at least over the first random number, the second random number, and the first session key;

determining with the user unit the first session key upon employment of a private user key;

checking with the user unit the digital signature;

sending with the user unit a second session key message to the program, said second session key message comprising at least the following components;

the second session key encrypted with a public key of the multiplexer component,

a digital signature or hash value formed at least over the first random number, the second random number, and the second session key;

receiving the second session key message with the multiplexer component;

checking the digital signature or the hash value with the multiplexer component; and

beginning the useful data transmission phase when the check supplies a positive result, whereby each entity employs the session key that it itself generated for the sending of data, and whereby the respectively received session key of the collaborating entity is employed exclusively for the reception of transmitted messages;

performing a check organization in the data flow organization unit to see whether the user unit from which the request was sent had originally started the program;

when the user unit sending the request had started the program, forwarding the request to the program;

when the user unit sending the request had not started the program, implementing an access control for the request on the basis of an access control data bank;

forwarding the request to the program when the access control shows that the request represents an allowed request; and

not forwarding the request to the program when the access control shows that the request represents an unallowed request.