Encryption data integrity check with dual parallel encryption engines

• US 8,171,282 B2
• Filed: 11/15/2007
• Issued: 05/01/2012
• Est. Priority Date: 11/15/2007
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Amann, Stefan, Banzhaf, Gerhard, Boyd, Kenneth W., Casper, Daniel F., Flanagan, John R., Palm, Jeffrey W., Yudenfriend, Harry M.
• Primary Examiner(s): Shiferaw, Eleni
• Assistant Examiner(s): FIELDS, COURTNEY D
• Application Number:
  US11/940,496
• Publication Number:
  US 20090132802A1
• Time in Patent Office: 1,629 Days
• Field of Search: 713/150, 713/193, 714/49, 380/44, 380/37
• US Class Current: 713/150
• CPC Class Codes: H04L 2209/125 Parallelization or pipelining, e.g. for accelerating processing of cryptographic operations
• CPC Class Codes: H04L 9/004 for fault attacks
• CPC Class Codes: H04L 9/0643 Hash functions, e.g. MD5, SHA, HMAC or f9 MAC

Abstract

An encryption method encrypts a clear text twice using a first encryption engine to produce a first cipher text and a second encryption engine to produce a second cipher text. The method compares the first cipher text with the second cipher text, or compares a checksum of the first cipher text with a checksum of the second cipher text. If the comparison succeeds, the method transmits the data. In some embodiments, the method uses a first instance of an encryption key to produce the first cipher text and a second instance of the encryption key to produce the second cipher text.

Claims

1. A method of providing integrity checks during data encryption, the method comprising:

encrypting a clear text by a first encryption engine using a first instance of an encryption key provided by a key manager to produce a first cipher text;

encrypting said clear text by a second encryption engine using a second, different instance of said encryption key to produce a second cipher text, wherein the second, different intance is provided by the key manager independent of the first instance of the encryption key;

determining whether the first instance of the encryption key and the second, different instance of the encryption key are identical and valid by comparing said first cipher text with said second cipher text; and

in response to the first cipher text and the second cipher text matching, indicating that the encryption keys are identical and valid and that no errors have occurred during encryption of said clear text, generating a cipher text checksum and appending the cipher text checksum to one of the first cipher text and the second cipher text.

2. The method as claimed in claim 1, further comprising:

transmitting said one of said first cipher text and said second cipher text to which the cipher text checksum is appended; and

storing one of said first cipher texts and said second cipher text if said cipher text matches said second cipher text.

5. The method as claimed in claim 1, wherein said comparing comprises:

generating a first checksum of said first cipher text;

generating a second checksum of said second cipher text; and

comparing said first and second checksums.

3. The method as claimed in 2, further comprising:

generating a first checksum on said clear text prior to said encrypting steps, wherein said first checksum is generated using a hash function;

reading said stored cipher text;

decrypting the cipher text that is read; and

checking said first checksum after said decrypting step.

4. The method as claimed in claim 3, further comprising:

generating the cipher text checksum as a second checksum for said one of said first cipher text and said second cipher text prior to said transmitting step; and

checking said second checksum to ensure data integrity of the cipher text prior storing the cipher text.

6. A method of encrypting data, the method comprising:

encrypting a clear text by a first encryption engine using a first instance of an encryption key to produce a first cipher text;

encrypting said clear text by a second encryption engine using a second instance of said encryption key to produce a second cipher text, wherein the second instance is provided independent of the first instance of the encryption key;

determining (a) whether the first instance of the encryption key and the second, different instance of the encryption key are identical and valid and (b) whether the encryption engines did not produce any errors during encryption of the clear text by comparing said first cipher text with said second cipher text; and

storing one of said cipher texts if said first cipher text matches said second cipher text, which indicates that the encryption keys are identical and valid and that the encryption engines did not produce any errors during encryption.

7. The method as claimed in claim 6, further comprising:

reading said stored cipher text; and

decrypting said read cipher text.

11. The method as claimed in claim 6, wherein said comparing comprises:

generating a first checksum of said first cipher text;

generating a second checksum of said second cipher text; and

comparing said checksum of said first cipher text with said checksum of said second cipher text to ensure encryption integrity, wherein encryption integrity is verified when the first checksum matches the second checksum.

8. The method as claimed in 7, further comprising:

generating a first checksum on said clear text prior to said encrypting steps; and

checking said first checksum after said decrypting step to ensure data integrity.

9. The method as claimed in claim 8, further comprising:

transmitting said one of said cipher texts prior to said storing step.

10. The method as claimed in claim 9, further comprising:

generating a second checksum on said one of said cipher texts prior to said transmitting step; and

checking said second checksum prior to said storing step to ensure data integrity.

12. An encryption method, which comprises:

encrypting a clear text by a first encryption engine using a first instance of an encryption key to produce a first cipher text;

encrypting said clear text by a second encryption engine using a second instance of said encryption key to produce a second cipher text, wherein the second, different instance is provided by a key manager independent of the first instance of the encryption key;

determining (a) whether the first instance of the encryption key and the second, different instance of the encryption key are identical and valid and (b) whether the encryption engines did not produce any errors during encryption of the clear text by comparing said first cipher text with said second cipher text;

in response to the first cipher text and the second cipher text matching, indicating that the encryption keys are identical and valid and that no errors have occurred during encryption of said clear text, generating a cipher text checksum and appending the cipher text checksum to one of the first cipher text and the second cipher text;

and transmitting one of said cipher texts if said first cipher text and said second cipher text match.

13. The method as claimed in claim 12, wherein said comparing comprises:

generating a checksum of said first cipher text;

generating a checksum of said second cipher text;

and comparing said checksum of said first cipher text with said checksum of said second cipher text.

14. The method as claimed in claim 13, wherein said transmitting comprises:

transmitting one of said cipher texts if said checksum of said first cipher text and said checksum of said second cipher text match.

15. The method as claimed in claim 12, wherein said comparing comprises:

generating a checksum of said first cipher text;

generating a checksum of said second cipher text; and

comparing said checksum of said first cipher text with said checksum of said second cipher text.

16. The method as claimed in claim 15, wherein said transmitting comprises:

transmitting one of said cipher texts if said checksum of said first cipher text and said checksum of said second cipher text match.