Method and system for establishing the identity of an originator of computer transactions

• US 8,234,699 B2
• Filed: 12/22/2004
• Issued: 07/31/2012
• Est. Priority Date: 12/31/2003
• Status: Active Grant

• Current Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Original Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Inventors: Pollutro, Dennis Vance, Almquist, Andrew A.
• Primary Examiner(s): Flynn, Nathan
• Assistant Examiner(s): WRIGHT, BRYAN F
• Application Number:
  US10/583,578
• Publication Number:
  US 20070283141A1
• Time in Patent Office: 2,778 Days
• Field of Search: 713/186
• US Class Current: 726/7
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 63/126 the source of the received data

Abstract

A method of identifying the originator of a message transmitted between a client and a server system is provided. The method includes modifying a message to be transmitted between a client and a server system to include a session identification flag and/or a session identifier 500 (e.g., at an end of the message). The method optionally includes one or more of the steps of re-computing a control portion of the message to reflect the inclusion of the session identification flag and the session identifier 502, transmitting the message between the client and the server system 504, and checking the transmitted message for the session identification flag 506, reading the session identifier of the transmitted message to determine the originator of the message 508, removing the session identification flag and/or the session identifier from the transmitted message 510, and re-computing the control portion of the message to reflect the removal of the session identification flag and/or the session identifier 512.

Claims

1. A method of identifying the originator of a message transmitted between a client and a server system, said method comprising the steps of:

modifying a message to be transmitted during a session between a client and a server system to include a session identification flag and a session identifier corresponding to an originator of the session on the server system and allowing the originator of the session to be uniquely identified among originators of sessions on the server system;

transmitting the message between the client and the server system;

checking the transmitted message for the session identification flag;

determining, in response to matching the session identification flag with a predefined value, that a valid session identifier has been included as a new portion of the transmitted message during the modification, the new portion available for extraction at a pre-established location within the transmitted message; and

extracting the session identifier of the transmitted message at the pre-established location to determine the originator of the message,

wherein if the appended session identifier in the transmitted message is not valid, processing the transmitted communication packet according to one or more predetermined rules for transmitted packets without valid session identifiers.

2. The method according to claim 1, wherein the step of modifying the message comprises the step of re-computing a control portion of the message to reflect the inclusion of the session identification flag and the session identifier.

3. The method according to claim 2, further comprising the steps of:

removing the session identification flag and the session identifier from the transmitted message; and

re-computing the control portion of the message to reflect the removal of the session identification flag and the session identifier.

4. The method according to claim 1, wherein the step of modifying the message comprises appending the session identification flag and the session identifier at an end of the message.

5. The method according to claim 1, wherein the step of modifying the message further comprises at least one of changing the session identifier for each communication or changing the session identifier at a predetermined interval.

6. A method of identifying the originator of a communication packet transmitted between a client and a server in a client/server system, said method comprising the steps of:

appending a session identifier and a security tag to the communication packet, the session identifier uniquely identifying the client in the client/server system;

determining, in response to matching the security tag with a predefined value, that a valid session identifier has been appended to form a new portion of the communication packet, the session identifier available for extraction at a pre-established location within the communication packet ; and

extracting the session identifier from the pre-established location to determine the originator of the transmitted communication packet,

wherein if the session identifier in the transmitted message is not valid, processing the transmitted communication packet according to one or more predetermined rules for transmitted packets without valid session identifiers.

7. The method according to claim 6, further comprising the step of:

establishing a common security tag in the client and server, wherein the step of appending the session identifier includes appending the common security tag to the communication packet to be transmitted between the client and the server such that a presence of the common security tag in the transmitted communication packet indicates that the session identifier is valid.

8. The method according to claim 6, wherein the step of appending the session identifier and the common security tag to the communication packet comprises the step of re-computing a control portion of the communication packet to be transmitted to reflect the inclusion of the common security tag and the session identifier, the method further comprising the steps of:

removing the common security tag and the session identifier from the transmitted communication packet; and

re-computing the control portion of the transmitted communication packet to reflect the removal of the common security tag and the session identifier.

9. The method according to claim 8, further comprising the steps of:

encrypting the communication packet to be transmitted after the step of appending the session identifier and the common security tag; and

decrypting the transmitted communication packet prior to the steps of determining the originator of the transmitted communication packet, removing the common security tag and the session identifier, and re-computing the control portion of the transmitted communication packet.

10. The method according to claim 8, further comprising the steps of:

encrypting the communication packet to be transmitted prior to the step of appending the session identifier and the common security tag; and

decrypting the transmitted communication packet after the step of re-computing the control portion of the transmitted communication packet.

11. The method according to claim 7, further comprising the step of:

setting a length of the common security tag greater than a predetermined length to reduce or substantially eliminate falsely authenticated session identifiers.

12. The method according to claim 11, wherein the length of the security tag is set to a length in the range of about 8 to 64 bits long.

13. A computer system for identifying the originator of a message, comprising

a server;

and

a client operationally connected to the server, the client and server being configured to transmit one or more messages there between during a session, each of the messages to be transmitted being modified by one of the client or the server to include a session identification flag and a session identifier. the client and server being further configured such that;

the modified message is transmitted to the remaining one of the client and the server;

the session identification flag of the transmitted message is checked by the remaining one of the client and the server to validate the session identifier;

the remaining one of the client and the server determines, in response to matching the session identification flag with a predefined value, that a valid session identifier has been included as a new portion of the transmitted message during the modification, the new portion available for extraction at a pre-established location within the transmitted message; and

the session identifier of the transmitted message is extracted from the pre-established location to determine the originator of the transmitted message, the session identifier corresponding to an originator of a session on the server system and allowing the originator of the session to be uniquely identified among originators of sessions on the server system,

wherein if the session identifier in the transmitted message is not valid, processing the transmitted communication packet according to one or more predetermined rules for transmitted packets without valid session identifiers.

14. The computer system according to claim 13 further comprising a network gateway disposed operationally between the client and server and providing access to the server such that the server is remotely accessible by the client.

15. The computer system according to claim 14 further comprising:

an encrypting unit disposed on one side of the network gateway to encrypt the message to be transmitted.

16. The computer system according to claim 15, further comprising:

a decrypting unit disposed on another side of the network gateway to decrypt the transmitted message.

17. The computer system according to claim 16, wherein the message is processed sequentially such that either the message to be transmitted is encrypted by the encrypting unit and then modified and the transmitted message is read and then decrypted by the decrypting unit or the message to be transmitted is modified and then encrypted by the encrypting unit and the transmitted message is decrypted by the decrypting unit and then read.

18. The computer system according to claim 14, wherein the network gateway includes a database to validate the session identifier by checking a user identifier, if the session identifier is not valid, the computer system forces the user to log in prior to accessing the server and if the session identifier is valid, the computer system retrieves an associated user identifier and the server processes the transmitted message.

19. A non-transitory computer readable storage medium including computer program instructions which cause a computer system including at least a client and a server to implement a method of identifying the originator of a message transmitted between the client and the server, said method comprising the steps of:

modifying a message to be transmitted during a session between the client and the server to include a session identification flag and a session identifier, the session identifier being assigned corresponding to the originator of the session on the server system and allowing the originator of the session to be uniquely identified among originators of sessions on the server system;

re-computing a control portion of the message to reflect the inclusion of the session identification flag and the session identifier;

transmitting the message between the client and the server;

checking the transmitted message for the session identification flag;

determining, in response to matching the session identification flag with a predefined value, that a valid session identifier has been included as a new portion of the transmitted message during the modification, the new portion available for extraction at a pre-established location within the transmitted message;

extracting the session identifier of the transmitted message from the pre-established location to determine the originator of the message;

removing the session identification flag and the session identifier from the transmitted message; and

re-computing the control portion of the message to reflect the removal of the session identification flag and the session identifier.

20. A method of identifying the originator of a message transmitted between a client and a server, comprising:

modifying, by a processor, a message to be transmitted during a session between a client and a server to include a session identification flag and a session identifier, the session identifier being assigned corresponding to the originator of the session on the server system and allowing the originator of the session to be uniquely identified among originators of sessions on the server system;

re-computing, by the processor, a control portion of the message to reflect the inclusion of the session identification flag and the session identifier;

transmitting the message between the client and the server;

checking the transmitted message for the session identification flag;

determining, in response to matching the session identification flag with a predefined value, that a valid session identifier has been included as a new portion of the transmitted message during the modification, the new portion available for extraction at a pre-established location within the transmitted message;

extracting the session identifier of the transmitted message from the pre-established location to determine the originator of the message;

removing the session identification flag and the session identifier from the transmitted message; and

re-computing, by the processor, the control portion of the message to reflect the removal of the session identification flag and the session identifier.