System and method for securely hyperlinking graphic objects

• US 20030110384A1
• Filed: 12/10/2002
• Published: 06/12/2003
• Est. Priority Date: 12/11/2001
• Status: Active Grant

• Current Assignee: X Corp. (f/k/a Twitter, Inc.) (X Holdings Corp.)
• Original Assignee: International Business Machines Corporation
• Inventors: Carro, Fernando Incertis
• Granted Patent: US 7,653,814 B2
• Time in Patent Office: Days
• US Class Current: 713/181
• CPC Class Codes: G06F 21/64 Protecting data integrity, e.g. using checksums, certificates or signatures
• CPC Class Codes: G06F 2221/2119 Authenticating web pages, e.g. with suspicious links
• CPC Class Codes: H04L 9/3242 involving keyed hash functions, e.g. message authentication codes [MACs], CBC-MAC or HMAC

Abstract

Systems and methods and computer programs for verifying the authenticity and integrity of hyperlink addresses and files that are accessible by means of these hyperlink addresses. A system and a method are disclosed for authenticating a file such as an HTML document hyperlinked to a graphic object such as a digital image or to a graphic icon. The hyperlink network address (e.g., the URL of the hyperlink on the Internet) is encoded on a first portion of the graphic object. Checking information such as a MAC digital signature and the hyperlinked file are encoded into a second portion of the same graphic object. In accordance with another aspect of the invention, a system and a method are disclosed for verifying the authenticity and integrity of a hyperlink and a file when this hyperlink is activated.

Claims

1. An authenticated hyperlink for accessing a file using a hyperlink address and for authenticating said hyperlink address and said file when said authenticated hyperlink is activated, said authenticated hyperlink comprising:

a digital image;

a first portion of the digital image comprising an encoded address of a file; and

a second portion of the digital image comprising an encoded message authentication code based on the address of the file and the file.

2. The authenticated hyperlink according to claim 1, wherein said message authentication code is also based on a secret key.

3. The authenticated hyperlink according to claim 1, wherein the message authentication code is computed to fit a predefined number of pixels in the second portion of the digital image.

4. The authenticated hyperlink according to claim 1, wherein the message authentication code is computed using a hash function having as inputs the address of the file, the file, and a secret key K.

5. The authenticated hyperlink according to claim 1, wherein the encoded address and the message authentication code are encoded in the digital image according to a least significant bit insertion method.

6. The authenticated hyperlink according to claim 1, wherein said authenticated hyperlink is embedded in an electronic document.

7. The authenticated hyperlink according to claim 1, wherein the file is located on a server connected to a network.

8. The authenticated hyperlink according to claim 7, wherein:

the network is an internet network;

the file is a Web page; and

the address is an Uniform Resource Locator (URL).

9. A method for creating an authenticated hyperlink to access a file by means of a hyperlink address and to authenticate said hyperlink address and said file when said authenticated hyperlink is activated, said method comprising the steps of:

providing a digital image;

encoding the address of a file in a first portion of said digital image;

computing a message authentication code based on the address of the file and the file; and

encoding the computed message authentication code in a second portion of said digital image.

10. The method according to claim 9, wherein said message authentication code is also based on a secret key.

11. The method according to claim 9, wherein the step of computing a message authentication code comprises the further step of:

specifying a format for the message authentication code to fit a predefined number of pixels in the second portion of the digital image.

12. The method according to claim 9, wherein the message authentication code is computed using a hash function having as inputs the address of the file, the file, and a secret key K.

13. The method according to claim 9, wherein the address and the message authentication code are encoded in the digital image according to a least significant bit insertion method.

14. The method according to claim 9, wherein the step of encoding the computed message authentication code in a second portion of said digital image, comprises the preliminary step of:

defining in said second portion of the digital image, a fixed number of pixels for encoding said message authentication code.

15. The method according to claim 9, further comprising the step of:

embedding the created authenticated hyperlink in an electronic document.

16. The method according to claim 9, wherein the file is located on a server connected to a network.

17. The method according to claim 16, wherein:

the network is an internet network,

the file is a Web page; and

the address is an Uniform Resource Locator (URL).

18. A computer program comprising instructions for carrying out the steps of the method for creating an authenticated hyperlink according to claim 9, when said computer program is executed.

19. A method for activating an authenticated hyperlink, said authenticated hyperlink comprising a digital image, said method comprising the steps of:

extracting from a first portion of said digital image, an encoded address of a file;

decoding said encoded address;

extracting from a second portion of said digital image, an encoded message authentication code;

decoding said encoded message authentication code;

accessing and retrieving the file corresponding to the decoded address;

computing a computed message authentication code by means of a hash function identical to the hash function used to compute the message authentication code encoded in the digital image;

comparing the computed message authentication code with the decoded message authentication code; and

if the computed message authentication code and the decoded message authentication code are identical, processing the file as being an authentic file.

20. A computer program comprising instructions for carrying out the steps of the method for activating an authenticated hyperlink according to claim 19 when said computer program is executed.