COMMUNICATION CHANNEL ACCESS BASED ON CHANNEL IDENTIFIER AND USE POLICY

• US 20100211792A1
• Filed: 02/17/2009
• Published: 08/19/2010
• Est. Priority Date: 02/17/2009
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Vinayak, Sai, Ureche, Octavian T., Semenko, Alex M., Ellison, Carl M.
• Granted Patent: US 8,296,564 B2
• Time in Patent Office: Days
• US Class Current: 713/176
• CPC Class Codes: H04L 63/102 Entity profiles
• CPC Class Codes: H04L 63/126 the source of the received data
• CPC Class Codes: H04L 9/3247 involving digital signatures

Abstract

A communication channel has an associated channel authenticator that includes a channel identifier, a use policy identifying how an owner of the communication channel indicates the communication channel is used, and a digital signature over the channel identifier and use policy. The identifier of the communication channel and the use policy can be verified by a computing device, and a check made as to whether a current security policy of the computing device is satisfied by the use policy. An access that the computing device is allowed to have to the communication channel is determined based at least in part on both whether the current security policy is satisfied by the use policy and whether the identifier of the communication channel and the use policy are verified.

Claims

1. A method implemented in a computing device, the method comprising:

obtaining an identifier of a communication channel;

obtaining a use policy identifying how an owner of the communication channel indicates the communication channel is used;

generating, using a private key of a public/private key pair of the owner, a digital signature over the identifier and the use policy; and

associating the identifier, the use policy, and the digital signature with the communication channel.

2. A method as recited in claim 1, wherein the communication channel comprises a removable storage device.

3. A method as recited in claim 2, wherein the use policy identifies how the owner indicates data stored on the removable storage device will be used.

4. A method as recited in claim 2, wherein the use policy identifies an entity that originated protection of the removable storage device.

5. A method as recited in claim 2, the associating comprising storing the use policy and the digital signature on the removable storage device.

6. A method as recited in claim 1, the obtaining comprising obtaining the identifier from the communication channel.

7. A method as recited in claim 1, the associating comprising storing the identifier, the use policy, and the digital signature on the communication channel.

8. A method as recited in claim 1, wherein the communication channel comprises a communication conduit.

9. A method as recited in claim 1, further comprising:

retrieving, from a communication channel authenticator of an additional communication channel, an additional channel identifier of the additional communication channel and an additional use policy identifying how an owner of the additional communication channel indicates the additional communication channel is used;

verifying the additional identifier and the additional use policy;

checking whether a current security policy of the computing device is satisfied by the additional use policy; and

determining, based at least in part on both whether the current security policy is satisfied by the additional use policy and whether the additional identifier and the additional use policy are verified, an access that the computing device is allowed to have to the additional communication channel.

10. A method as recited in claim 9, wherein the additional communication channel comprises a removable storage device, and wherein the determining comprises allowing read-write access to the removable storage device only if an entity that originated protection of the removable storage device is a same entity as an entity that implements a security policy protecting the computing device, the entity that originated protection of the removable storage device being identified in the additional use policy

11. A method implemented in a computing device, the method comprising:

retrieving, from a communication channel authenticator of a communication channel, an identifier of the communication channel and a use policy identifying how an owner of the communication channel indicates the communication channel is used;

verifying the identifier of the communication channel and the use policy;

checking whether a current security policy of the computing device is satisfied by the use policy; and

determining, based at least in part on both whether the current security policy is satisfied by the use policy and whether the identifier of the communication channel and the use policy are verified, an access that the computing device is allowed to have to the communication channel.

12. A method as recited in claim 11, wherein the communication channel comprises a removable storage device.

13. A method as recited in claim 12, the determining comprising allowing read-write access to the removable storage device only if an entity that originated protection of the removable storage device is a same entity as an entity that implements a security policy protecting the computing device, the entity that originated protection of the removable storage device being identified in the use policy.

14. A method as recited in claim 11, wherein the access is read-only access if one or more of the current security policy is not satisfied, the identifier of the communication channel is not verified, or the use policy is not verified.

15. A method as recited in claim 14, wherein the access is read-write access if the current security policy is satisfied, the identifier of the communication channel is verified, and the use policy is verified.

16. A method as recited in claim 11, the verifying comprising using a digital signature in the communication channel authenticator to verify that the identifier and the use policy have not been changed since the digital signature was generated.

17. A method as recited in claim 16, the determining being further based at least in part on a trust level that the computing device has for the owner.

18. A method as recited in claim 11, wherein the communication channel comprises a communication conduit.

19. One or more computer storage media having stored thereon multiple instructions that, when executed by one or more processors of a computing device, cause the one or more processors to:

obtain, from an authenticator of a removable storage device, a first identifier of the removable storage device;

obtain, from the authenticator, a second identifier of an entity that originated protection of the removable storage device;

verify a digital signature over the first identifier and the second identifier to confirm that the first identifier and the second identifier have not been changed since the digital signature was generated;

check whether the entity that enabled protection of the removable storage device is a same entity as implements a security policy protecting the computing device; and

allow the computing device read-write access to the removable storage device if the entity that enabled protection of the removable storage device is the same entity as implements the security policy protecting the computing device, otherwise allow the computing device read-only access to the removable storage device.

20. One or more computer storage media as recited in claim 19, the multiple instructions further causing the one or more processors to allow the computing device to have read-only access to the removable storage device if the digital signature is not verified.