Systems and Methods Using Cryptography to Protect Secure Computing Environments

• US 20100023761A1
• Filed: 07/20/2007
• Published: 01/28/2010
• Est. Priority Date: 08/12/1996
• Status: Abandoned Application

• Current Assignee: Intertrust Technologies Corporation (Fidelio Acquisition Co LLC)
• Original Assignee: Intertrust Technologies Corporation (Fidelio Acquisition Co LLC)
• Inventors: Shear, Victor H., Sibert, W. Olin, Van Wie, David M.
• Application Number:
  US11/781,062
• Publication Number:
  US 20100023761A1
• Time in Patent Office: Days
• US Class Current: 713/166
• CPC Class Codes: G06F 12/1483 using an access-table, e.g. matrix or list
• CPC Class Codes: G06F 21/10 Protecting distributed programs or content, e.g. vending or licensing of copyrighted material protection in video systems or pay television H04N7/16 ; Digital rights management [DRM]
• CPC Class Codes: G06F 21/51 at application loading time, e.g. accepting, rejecting, starting or inhibiting executable software based on integrity or source reliability
• CPC Class Codes: G06F 2211/007 Encryption, En-/decode, En-/decipher, En-/decypher, Scramble, (De-)compress
• CPC Class Codes: G06Q 20/02 involving a neutral party, e.g. certification authority, notary or trusted third party [TTP]
• CPC Class Codes: G06Q 20/085 involving remote charge determination or related payment systems
• CPC Class Codes: G06Q 20/12 specially adapted for electronic shopping systems
• CPC Class Codes: G06Q 20/24 Credit schemes, i.e. "pay after"
• CPC Class Codes: G06Q 20/3674 involving authentication
• CPC Class Codes: G06Q 20/3823 combining multiple encryption tools for a transaction
• CPC Class Codes: G06Q 20/3825 Use of electronic signatures
• CPC Class Codes: G06Q 20/401 Transaction verification
• CPC Class Codes: G11B 20/00086 Circuits for prevention of unauthorised reproduction or copying, e.g. piracy indicating unauthorised use of record carriers in general G11B23/28; scrambling for television signal recording H04N5/913; network architectures or network protocols for network security H04L63/00; cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00
• CPC Class Codes: G11B 20/00159 Parental control systems
• CPC Class Codes: G11B 20/00173 wherein the origin of the content is checked, e.g. determining whether the content has originally been retrieved from a legal disc copy or another trusted source
• CPC Class Codes: G11B 20/00188 involving measures which result in a restriction to authorised devices recording or reproducing contents to/from a record carrier
• CPC Class Codes: G11B 20/00195 using a device identifier associated with the player or recorder, e.g. serial numbers of playback apparatuses or MAC addresses
• CPC Class Codes: G11B 20/0021 involving encryption or decryption of contents recorded on or reproduced from a record carrier
• CPC Class Codes: G11B 20/00543 wherein external data is encrypted, e.g. for secure communication with an external device or for encrypting content on a separate record carrier
• CPC Class Codes: G11B 20/00557 wherein further management data is encrypted, e.g. sector headers, TOC or the lead-in or lead-out areas
• CPC Class Codes: G11B 20/00688 : said measures preventing that a usable copy of recorded data can be made on another medium
• CPC Class Codes: G11B 20/0071 : involving a purchase action
• CPC Class Codes: G11B 20/00768 : wherein copy control information is used, e.g. for indicating whether a content may be copied freely, no more, once, or never, by setting CGMS, SCMS, or CCI flags
• CPC Class Codes: G11B 2220/216 : Rewritable discs
• CPC Class Codes: G11B 2220/218 : Write-once discs
• CPC Class Codes: G11B 2220/2562 : DVDs [digital versatile discs]; Digital video discs; MMCDs; HDCDs
• CPC Class Codes: G11B 2220/2575 : DVD-RAMs
• CPC Class Codes: G11B 27/031 : Electronic editing of digitised analogue information signals, e.g. audio or video signals
• CPC Class Codes: G11B 27/329 : on a disc [VTOC]
• CPC Class Codes: H04L 12/40104 : Security; Encryption; Content protection cryptographic protocols H04L9/00; protocols for network security H04L63/00
• CPC Class Codes: H04L 12/40117 : Interconnection of audio or video/imaging devices home automation networks H04L12/2803; bitstream network arrangements specially adapted for distribution of digital video signals H04N7/24

Abstract

Secure computation environments are protected from bogus or rogue load modules, executables and other data elements through use of digital signatures, seals and certificates issued by a verifying authority. A verifying authority—which may be a trusted independent third party—tests the load modules or other executables to verify that their corresponding specifications are accurate and complete, and then digitally signs the load module or other executable based on tamper resistance work factor classification. Secure computation environments with different tamper resistance work factors use different verification digital signature authentication techniques (e.g., different signature algorithms and/or signature verification keys)—allowing one tamper resistance work factor environment to protect itself against load modules from another, different tamper resistance work factor environment. Several dissimilar digital signature algorithms may be used to reduce vulnerability from algorithm compromise, and subsets of multiple digital signatures may be used to reduce the scope of any specific compromise.

Claims

1. A method comprising:

associating a first digital certificate with a first piece of software, the first digital certificate designating the first piece of software for use in a first class of computing environments;

associating a second digital certificate with a second piece of software, the second digital certificate designating the second piece of software for use in a second class of computing environments having a security level that is higher than that of a security level of the first class of computing environments;

wherein a computing environment in the second class is operable to evaluate the first digital certificate and refuse to execute the first piece of software; and

wherein the computing environment in the second class is further operable to evaluate the second digital certificate and allow execution of the second piece of software.

2. The method of claim 1, further including the step of conditionally executing, based at least in part on evaluating the first digital certificate, the first piece of software in a first computing environment within the first class of computing environments.

3. The method of claim 2, further including the step of conditionally executing, based at least in part on evaluating the second digital certificate, the second piece of software in a second computing environment different from the first computing environment, the second computing environment being within the second class of computing environments.

4. The method of claim 1, in which the first class of computing environments comprises personal computers having a first security level, and in which the second class of computing environments comprises personal computers having a second security level.

5. A method of distinguishing between trusted and untrusted piece of software, the method comprising:

receiving a piece of software at a computer system;

determining whether the piece of software has an associated digital certificate;

if the piece of software has an associated digital certificate, evaluating the digital certificate using at least one key, the key being protected, at least in part, from being replaced by a user of the computer system; and

conditionally executing the piece of software based at least in part on results of the evaluating step.

6. The method of claim 5, in which the key is secured behind a tamper resistant barrier.

7. The method of claim 5, in which the key'"'"'s value is protected, at least in part, from being disclosed to a user of the computer system.

8. The method of claim 5, in which the key'"'"'s value is not kept secret from users of the computer system.

9. A method for protecting a first computing environment, the first computing environment having a first security level, the method including:

preventing the first computing environment from using a piece of software accessible by a second computing environment having a second security level different from the first security level.

10. The method of claim 9, in which the preventing step includes:

evaluating at least one digital certificate associated with the first computing environment.

11. The method of claim 9, in which the preventing step includes:

evaluating at least one digital certificate associated with the piece of software.