Method and system for caching virus-free file certificates

• US 20010020272A1
• Filed: 12/04/2000
• Published: 09/06/2001
• Est. Priority Date: 01/06/2000
• Status: Active Grant

• Current Assignee: Akara Corp. (Ciena Corporation), Trend Micro Inc.
• Original Assignee: Akara Corp. (Ciena Corporation)
• Inventors: Hericourt, Olivier, Le Pennec, Jean-Francois
• Granted Patent: US 6,892,303 B2
• Time in Patent Office: Days
• US Class Current: 713/200
• CPC Class Codes: G06F 21/00 Security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
• CPC Class Codes: G06F 21/566 Dynamic detection, i.e. detection performed at run-time, e.g. emulation, suspicious activities
• CPC Class Codes: G06F 21/645 using a third party

Abstract

The present invention relates to computer viruses and more particularly to a method and system, for use in a virus-free certificate cache (106), of caching one or multiple virus-free certificates (200), each virus-free certificate certifying that a file is virus-free. The method comprises the steps of:

receiving (601) a virus-free certificate request for a file;

identifying (602) the file in a cache table (501), the cache table (501) comprising for each identified file (502) one or a plurality of virus-free certificates (509);

selecting in the cache table (501) one virus-free certificate (509) for the identified file (502), using one or a plurality of anti-virus criteria;

retrieving (602) from the cache table (501) the selected virus-free certificate (509);

sending back (606) in response to the virus-free certificate request the retrieved virus-free certificate.

Claims

1. A method, for use in a virus-free certificate cache, of caching one or multiple virus-free certificates, each virus-free certificate certifying that a file is virus-free, said method comprising the steps of:

receiving a virus-free certificate request for a file;

identifying the file in a cache table, said cache table comprising for each identified file one or a plurality of virus-free certificates;

selecting in the cache table one virus-free certificate for the identified file, using one or a plurality of anti-virus criteria;

retrieving from the cache table said selected virus-free certificate;

sending back in response to the virus-free certificate request the retrieved virus-free certificate.

2. The method according to

claim 1

wherein the virus-free certificate request comprises:

a list of one or a plurality of anti-virus programs to execute on the file to determine whether the file is virus-free or not.

3. The method according to

claim 1

wherein the virus-free certificate request further comprises:

an identification of the file.

4. The method according to the

claim 1

wherein the virus-free certificate request further comprises:

an identification of a virus-free certificate authority, said virus-free certificate authority having authority to generate virus-free certificates.

5. The method according to

claim 1

wherein the virus-free certificate comprises:

the list of the one or plurality of anti-virus programs that have been executed on the file.

6. The method according to

claim 1

wherein the virus-free certificate further comprises:

a virus-free certificate authority identification.

7. The method according to

claim 1

wherein the step of selecting in the cache table one virus-free certificate for the identified file using one or a plurality of anti-virus criteria comprises the further steps of:

comparing the list of one or a plurality of anti-virus programs comprised in each virus-free certificate associated with the identified file in the cache table with the list of one of a plurality of anti-virus programs comprised in the received virus-free/certificate request;

and where the list of one of a plurality of anti-virus programs comprised in a virus-free certificate associated with the identified file includes the list of one or a p lurality of anti-virus programs comprised in the received virus-free certificate request;

selecting said virus-free certificate.

8. The method according to

claim 1

wherein the step of selecting in the cache table one virus-free certificate for the identified file using one or a plurality anti-virus criteria comprises the further steps of:

comparing the virus-free certificate authority identification comprised in each virus-free certificate associated with the identified file in the cache table, and the virus-free certificate authority identification comprised in the received virus-free certificate request;

and where the virus-free certificate authority identification comprised in a virus-free certificate associated with the identified file is identical to the virus-free certificate authority identification comprised in the received virus-free certificate request;

selecting said virus-free certificate.

9. The method according to

claim 1

wherein the step of identifying the file in a cache table comprises the further steps of:

If the file is not identified in said cache table;

forwarding the received virus-free certificate request to another virus-free certificate cache;

receiving a virus-free certificate in response to said forwarded virus-free certificate request;

sending back in response to the received virus-free certificate request, said received virus-free certificate.

10. The method according to

claim 1

comprising the further step of:

receiving a request to update the cache table, said request comprising a virus-free certificate;

storing said virus-free certificate in the cache table.

11. The method according to

claim 10

wherein the step of receiving a request to update the cache table comprises the further step of:

forwarding said request to another virus-free certificate cache.

12. The method according to

claim 1

comprising the further step of:

discarding from the cache table the virus-free certificate which are no more valid.

13. The method according to

claim 1

comprising the further steps of:

selecting in the cache table one or a plurality of virus-free certificates, using an information indicating for each virus-free certificate the date of the latest virus-free certificate request which has been received for said virus-free certificate;

discarding from the cache table said one or plurality of selected virus-free certificate.

14. The method according to

claim 1

comprising the further steps of:

selecting in the cache table one or a plurality of virus-free certificate, using an information indicating for each virus-free certificate the number of virus-free certificate request which have been received for said virus-free certificate;

discarding from the cache table said one or a plurality of selected virus-free certificate Comprises.

15. The method according to

claim 1

wherein the generated virus-free certificate comprises:

a file signature for certifying that the file is declared a virus-free by the selected virus-free certificate authority.

16. The method according to

claim 1

wherein the virus-free-certificate further comprises:

a file identification;

a public key for decrypting the file signature;

a certificate signature for authenticating the virus-free certificate;

an indication of the virus-free certificate validity.

17. A system for caching one or more virus-free certificates within a LAN/WAN network, each virus-free certificate certifying that a file to be downloaded to a client is virus-free, said system comprising:

a mechanism for receiving a request for a virus-free certificate associated with a file to be downloaded to said client;

cache table device for storing one or more virus-free certificates for files, said cache table device including look-up mechanism for identifying one or more virus-free certificates associated with a requested file in a cache table;

said look-up mechanism enabling selection of one virus-free certificate for the identified file using one or a plurality of anti-virus criteria; and

,

mechanism for retrieving from a cache table said selected virus-free certificate; and

, in response to said request, returning a retrieved virus-free certificate with said file.

18. A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform method steps for caching one or more virus-free certificates within a LAN/WAN network, each virus-free certificate certifying that a file to be downloaded to a client is virus-free, said method steps comprising:

a) receiving a virus-free certificate request for a file;

b) identifying the file in a cache table, said cache table comprising for each identified file one or plurality of virus-free certificates;

c) selecting in the cache table one virus-free certificate for the identified file using one or a plurality of anti virus criteria; and

,

d) retrieving from the cache table said selected virus-free certificate and returning a retrieved virus-free certificate with said file.