Encryption algorithm with randomized buffer

• US 9,059,838 B2
• Filed: 03/30/2007
• Issued: 06/16/2015
• Est. Priority Date: 03/30/2007
• Status: Active Grant

• Current Assignee: Verizon Patent and Licensing Incorporated (Verizon Communications Inc.)
• Original Assignee: Verizon Patent and Licensing Incorporated (Verizon Communications Inc.)
• Inventors: Coomer, Brad
• Primary Examiner(s): Khoshnoodi, Nadia
• Application Number:
  US11/694,041
• Publication Number:
  US 20110182419A1
• Time in Patent Office: 3,000 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: H04L 2209/20 Manipulating the length of blocks of bits, e.g. padding or block truncation
• CPC Class Codes: H04L 9/0656 Pseudorandom key sequence combined element-for-element with data sequence, e.g. one-time-pad [OTP] or Vernam's cipher
• CPC Class Codes: H04L 9/0662 with particular pseudorandom sequence generator
• CPC Class Codes: H04L 9/0891 Revocation or update of secret information, e.g. encryption key update or rekeying

Abstract

A system obtains a key and first and second plaintext, where the first plaintext is identical to the second plaintext. The system uses the key to encrypt the first plaintext to a first ciphertext and the second plaintext to a second ciphertext using a same encryption algorithm, where the first ciphertext is different than the second ciphertext.

Claims

1. A method, comprising:

obtaining, by a device, a first item of plaintext, a second item of plaintext, and an encryption key,

the second item of plaintext being identical to the first item of plaintext;

appending, by the device, first randomized data to an end of the first item of plaintext and second randomized data to an end of the second item of plaintext;

encrypting, by the device, the first item of plaintext, including the appended first randomized data, using an encryption algorithm and the encryption key to produce first ciphertext,

the encrypting the first item of plaintext including iteratively encrypting a plurality of data segments of the first item of plaintext,

an iteration of encrypting a data segment of the plurality of data segments including;

determining a first value based on the encryption key and the data segment of the first item of plaintext, determining whether the first value comprises more than a threshold quantity of bits,

reducing the first value to comprise the threshold quantity of bits when the first value comprises more than the threshold quantity of bits to form a second value,

adding a predetermined value, to the first value, to obtain a third value when the first value does not comprise more than the threshold quantity of bits,

determining whether the third value comprises more than the threshold quantity of bits, and

reducing the third value to comprise the threshold quantity of bits to obtain a fourth value when the third value comprises more than the threshold quantity of bits,

the first ciphertext including a cypher value for the data segment, the cypher value comprising;

 

the second value when the first value comprises more than the threshold quantity of bits,

 

the third value when the third value does not comprise more than the threshold quantity of bits, or

 

the fourth value when the third value comprises more than the threshold quantity of bits; and

encrypting, by the device, the second item of plaintext, including the appended second randomized data, using the encryption algorithm and the encryption key to produce second ciphertext,

the second ciphertext being different than the first ciphertext.

2. The method of claim 1, further comprising:

decrypting the first ciphertext and the second ciphertext using a same decryption algorithm to produce the first item of plaintext and the second item of plaintext.

3. The method of claim 1, where encrypting the first item of plaintext further includes:

segmenting the first item of plaintext into the plurality of data segments based on a number of bits associated with the first item of plaintext, and

encrypting each data segment, of the plurality of data segments, using the encryption algorithm and the encryption key.

4. The method claim 1, further comprising:

generating the first randomized data based on a time at which the first randomized data is generated; and

generating the second randomized data based on a time at which the second randomized data is generated,

where the time at which the second randomized data is generated is different from the time at which the first randomized data is generated.

5. The method of claim 4, where encrypting the first item of plaintext includes:

segmenting the first item of plaintext, including the appended first randomized data, into the plurality of data segments;

altering the encryption key to obtain a different key value for each data segment of the plurality of data segments of the first item of plaintext; and

determining a different cipher value for each data segment of the plurality of data segments of the first item of plaintext based on the different key value.

6. The method of claim 5, where the first ciphertext is based on the different cipher value determined for each data segment of the plurality of data segments of the first item of plaintext.

7. The method of claim 1, where the plurality of data segments of the first item of plaintext are a plurality of first data segments,

where encrypting the second item of plaintext includes:

segmenting the second item of plaintext into a second plurality of data segments;

altering the encryption key to obtain a different key value for each second data segment, of the plurality of second data segments, of the second item of plaintext; and

determining a different cipher value for each second data segment of the plurality of second data segments, of the second item of plaintext, based on the different key value.

8. The method of claim 7, where the second ciphertext is based on the different cipher value determined for each second data segment of the plurality of second data segments of the second item of plaintext.

9. A system, comprising:

a first data buffer, at least partially implemented in hardware, to store first plaintext and second plaintext,

the first plaintext being identical to the second plaintext; and

an encryption module, at least partially implemented in hardware, to;

append first randomized data to an end of the first item of plaintext and second randomized data to an end of the second item of plaintext;

encrypt the first plaintext, including the appended first randomized data, using a particular encryption algorithm and a key to produce a first ciphertext,

the encrypting the first plaintext including iteratively encrypting a plurality of data segments of the first plaintext,

the encryption module, for an iteration of encrypting a data segment of the plurality of data segments, being to;

determine a first value based on the key and the data segment of the plurality of data segments of the first plaintext,

determine whether the first value comprises more than a threshold number of bits,

reduce the first value to comprise the threshold number of bits when the first value comprises more than the threshold number of bits to form a second value,

add a predetermined value, to the first value, to obtain a third value when the first value does not comprise more than the threshold number of bits,

determine whether the third value comprises more than the threshold number of bits, and

reduce the third value to comprise the threshold number of bits to obtain a fourth value, when the third value comprises more than the threshold number of bits, and

 

the first ciphertext including a cypher value for the data segment, the cypher value comprising;

 

the second value when the first value comprises more than the threshold number of bits,

 

the third value when the third value does not comprise more than the threshold number of bits, or

 

the fourth value when the third value comprises more than the threshold number of bits, and

encrypt the second plaintext, including the appended second randomized data, using the particular algorithm and the key to produce a second ciphertext,

the first ciphertext being different than the second ciphertext.

10. The system of claim 9, comprising:

a second data buffer to store the first ciphertext and the second ciphertext; and

a decryption module to;

use the key and a particular decryption algorithm to;

decrypt the first ciphertext to produce the first plaintext, and

decrypt the second ciphertext to produce the second plaintext.

11. The system of claim 9, further comprising:

a random data generator to produce the first random data and the second random data,

where the first random data is different than the second random data, where the first data buffer is further to;

store the first random data at a first location identified by a first buffer pointer, and

store the second random data at a second location identified by a second buffer pointer; and

where, when encrypting the first plaintext, the encryption module is further to;

segment the first plaintext, including the first random data, into the plurality of data segments,

segmenting the first plaintext being based on the first pointer and a number of bits associated with the first plaintext.

12. The system of claim 9, where the encryption module is further to:

segment the first plaintext into the plurality of data segments,

alter the key to obtain a different key value for each data segment of the plurality of data segments, and

determine a different cipher value for each data segment of the plurality of data segments based on a respective different key value.

13. The system of claim 12, where the encryption module is further to use the key to encrypt the first plaintext to produce the first ciphertext based on the different cipher value determined for each data segment of the of the plurality of data segments.

14. The system of claim 13, where the plurality of data segments are a plurality of first data segments,

where the encryption module is further to:

segment the second plaintext into a plurality of second data segments,

alter the key to obtain a different key value for each second data segment of the plurality of second data segments of the second plaintext, and

determine a different cipher value for each second data segment of the plurality of second data segments of the second plaintext, based on a respective different key value.

15. The system of claim 14, where the encryption module is further to use the key to encrypt the second plaintext to obtain the second ciphertext based on the different cipher value for each second data segment of the plurality of second data segments.

16. A method, comprising:

obtaining, by a device, plaintext and an encryption key;

appending, by the device, randomized data to the plaintext;

encrypting, by the device and based on the encryption key, the plaintext, including the randomized data, to produce ciphertext,

the encrypting the plain text including iteratively encrypting a plurality of data segments of the plaintext,

an iteration of encrypting a data segment of the plurality of data segments including;

determining a first value based on the encryption key and the data segment of the plaintext,

determining whether the first value comprises more than a threshold quantity of bits,

reducing the first value to comprise the threshold quantity of bits when the first value comprises more than the threshold quantity of bits to form a second value,

adding a predetermined value, to the first value, to obtain a third value when the first value does not comprise more than the threshold quantity of bits,

determining whether the third value comprises more than the threshold quantity of bits, and

reducing the third value to comprise the threshold quantity of bits to obtain a fourth value when the third value comprises more than the threshold quantity of bits,

the ciphertext including a cypher value for the data segment, the cypher value comprising;

 

the second value when the first value comprises more than the threshold quantity of bits,

 

the third value when the third value does not comprise more than the threshold quantity of bits, or

 

the fourth value when the third value comprises more than the threshold quantity of bits.

17. The method of claim 16, further comprising:

generating the randomized data based on a time at which the randomized data is generated.

18. The method of claim 16, further comprising:

storing the randomized data at a location identified by a pointer to append the randomized data to an end of the plaintext;

segmenting the plaintext, including the randomized data, into the plurality of data segments based on the pointer and a quantity of bits associated with the plaintext;

altering the encryption key to obtain a different key value for each data segment of the plurality of data segments; and

determining a different cipher value for each data segment, of the plurality of data segments, based on the different key value obtained for the data segment.

19. The method of claim 18, where encrypting the plaintext to produce the ciphertext further comprises:

using the encryption key to encrypt the plurality of data segments based on the different cipher value determined for each data segment of the plurality of data segments.