M6 block cipher system and method for encoding content and authenticating a device

• US 7,613,296 B2
• Filed: 10/26/2005
• Issued: 11/03/2009
• Est. Priority Date: 11/26/2004
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Choi, Hong-Mook, Noh, Mi-Jung
• Primary Examiner(s): Colin; Carl
• Assistant Examiner(s): SHEHNI, GHAZAL B
• Application Number:
  US11/258,059
• Publication Number:
  US 20060126834A1
• Time in Patent Office: 1,469 Days
• Field of Search: 380 28- 29, 380/37, 380249-255, 380/262
• US Class Current: 380/37
• CPC Class Codes: H04L 2209/08 Randomization, e.g. dummy operations or using noise
• CPC Class Codes: H04L 2209/12 Details relating to cryptographic hardware or logic circuitry
• CPC Class Codes: H04L 9/0625 with splitting of the data block into left and right halves, e.g. Feistel based algorithms, DES, FEAL, IDEA or KASUMI

Abstract

An M6 block cipher system and method for encoding content and authenticating a device may use an M6 core. The M6 block cipher system may include a rotate constant selector selecting one or more rotate constants from a plurality of input rotate constants for output based on a selection signal input thereto, a rotate constant ordering device ordering the selected rotate constants and a common rotate constant input thereto based on a received ordering signal and an M6 core generating one or more of an output signal, a validity signal and a round number based on the ordered rotate constants and a plurality of input signals. The system may include a rotate constant scheduler outputting the ordering signal to the rotate constant ordering device in response to the selection signal and the round number.

Claims

1. An M6 block cipher system, comprising:

a rotate constant selector device selecting one or more rotate constants from a plurality of input rotate constants for output based on a selection signal input thereto,

a rotate constant ordering device ordering the selected rotate constants and a common rotate constant input thereto based on a received ordering signal,

an M6 core device generating one or more of an output signal, a validity signal and a round number based on the ordered rotate constants and a plurality of input signals, and

a rotate constant scheduler device outputting the ordering signal to the rotate constant ordering device in response to the selection signal and the round number.

2. The system of claim 1, wherein the selection signal determines whether to encode content or to generate a random number and create an exchange key for device authentication.

3. The system of claim 1, wherein the plurality of rotate constants input to the rotate constant selector includes two rotate constants used to encode content, and two rotate constants used to generate the random number and create an exchange key for device authentication.

4. The system of claim 1, wherein the ordering signal indicates the order of the selected rotate constants to be used for a round operation.

5. The system of claim 1, wherein the common rotate constant is used to encode content and for device authentication.

6. The system of claim 1, wherein the input signals to the M6 core include one or more of an input text signal, a key signal, an operation start signal and a mode selection signal.

7. The system of claim 1, wherein the input signals to the M6 core include each of a key signal, an operation start signal, a mode selection signal and an input text signal.

8. The system of claim 7, wherein the operation start signal instructs the M6 core to start operation,

the key signal is used to create two round operation keys, one key for each round of operation of the M6 core, and

the mode selection signal instructs the M6 core as to whether to encode or decode a given input text signal.

9. The system of claim 8, wherein

if the given input text signal is plain text, the mode selection signal instructs the M6 core to encode the input plain text signal, else

if the given input text signal is cipher text, the mode selection signal instructs the M6 core to decode the input cipher text signal.

10. The system of claim 1, wherein the M6 core outputs each of an output signal, a validity signal and a round number based on the ordered rotate constants and plurality of input signals.

11. The system of claim 10, wherein

the round number contains information on a present round operation,

the output signal is generated by encoding or decoding the one a given input text signal contained in the input signals to the M6 core, and

the validity signal indicates an end of encoding and decoding and the validity of an encoded or decoded value in response to a given rotate constant.

12. The system of claim 1, wherein the M6 block cipher system performs a single round during a single clock cycle.

13. The system of claim 1, wherein the M6 core comprises:

a first multiplexer which, in a first round operation, selects one of the input signals and a round output signal for output, in response to a first control signal,

an M6 core controller generating the first control signal that instructs the first multiplexer to select a given input signal in the first round operation, the round output signal in another round operation, and the validity signal in response to the round number,

a round key generator generating first and second round operation keys in response to a key signal used to create the two round operation keys, one key for each round of operation of the M6 core, and

a Pi function generating the round output signal by performing a round operation on an output signal of the first multiplexer and outputting the round output signal and the round number in response to the ordered rotate constants, the first and second operation keys, and a mode selection signal to instruct the M6 core as to whether to encode or decode a given one of the input signals.

14. The system of claim 13, wherein the M6 core further receives a first operation start signal that instructs the M6 core to start operating, and the M6 core controller operates in response to the first operating start signal.

15. The system of claim 13, wherein the M6 core controller further outputs a second operation start signal that instructs the Pi function to perform the round operation.

16. The system of claim 13, wherein

an output signal of the first multiplexer is divided into consecutive first and second data streams, and

the Pi function comprises:

a first basic operation device performing a basic operation using the first round operation key and the first data stream,

a first rotate function rotating an output signal of the first basic operation device a number of positions equal to the value of a first ordered rotate constant of the ordered rotate constants,

a second basic operation device performing the basic operation using an output signal of the first rotate function, the output signal of the first basic operation device, and a constant “

1”

,

a second rotate function rotating an output signal of the second basic operation device a number of positions equal to the value of a second ordered rotate constant of the rotate constants,

a third basic operation device performing the basic operation using the output signal of the second basic operation device, an output signal of the second rotate function, and the second round operation key,

a third rotate function rotating an output signal of the third basic operation device a number of positions equal to the value of a third ordered rotate constant of the rotate constants, and

a fourth basic operation device performing the basic operation using the mode selection signal, the output signal of the third basic operation device, an output signal of the third rotate function, and the second data stream, and

wherein the basic operation is selected from one of an addition operation, a subtraction operation, and an operation of the locations of the basic operation devices.

17. The system of claim 16, wherein the output signal of the first multiplexer contains 64 bits, and each of the first data stream and the second data stream includes 32 bits.

18. An M6 block cipher system that performs a plurality of round operations in order to authenticate a device for receiving/transmitting content and encoding content, in which each of the plurality of round operations includes a plurality of sub round operations, the system comprising:

a rotate constant selector device selecting one or more rotate constants from a plurality of input rotate constants for output based on a selection signal input thereto,

a rotate constant ordering device ordering, for output, each of the selected rotate constants, a separately received common rotate constant and a separately received non-common rotate constant, in response to the rotate constant selection signal,

an M6 core device generating one or more of an output signal, a validity signal, a round number and a sub round number based on the ordered rotate constants and a plurality of input signals, and

a rotate constant scheduler device outputting the ordering signal to the rotate constant ordering device in response to the selection signal, the round number and the sub round number.

19. The system of claim 18, wherein the selection signal determines whether to encode content or to generate a random number and create an exchange key for device authentication.

20. The system of claim 18, wherein the plurality of rotate constants input to the rotate constant selector includes two rotate constants used to encode content, and two rotate constants used to generate the random number and create an exchange key for device authentication.

21. The system of claim 18, wherein the ordering signal indicates the order of the selected rotate constants to be used for a round operation.

22. The system of claim 18, wherein

the common rotate constant is used to encode content and for device authentication, and

the non-common rotate constant is used when an output signal is not rotated.

23. The system of claim 18, wherein the input signals to the M6 core include one or more of an input text signal, a key signal, an operation start signal and a mode selection signal.

24. The system of claim 18, wherein the input signals to the M6 core include each if a key signal, an operation start signal, a mode selection signal and an input text signal.

25. The system of claim 24, wherein

the operation start signal instructs the M6 core to start operation,

the key signal is used to create two round operation keys, one key for each round of operation of the M6 core, and

the mode selection signal instructs the M6 core as to whether to encode or decode a given input text signal.

26. The system of claim 25, wherein

if the given input text signal is plain text, the mode selection signal instructs the M6 core to encode the input plain text signal, else

if the given input text signal is cipher text, the mode selection signal instructs the M6 core to decode the input cipher text signal.

27. The system of claim 18, wherein the M6 core outputs each of an output signal, a validity signal, a round number and a sub round number based on the ordered rotate constants and plurality of input signals.

28. The system of claim 27, wherein

the round number generated by the M6 core contains information on a present round operation,

the sub round number contains information on a present sub round operation performed in the present round,

the output signal is generated by encoding or decoding one of an input plain text or an input cipher text signal which are contained in the input signals to the M6 core, and

the validity signal indicates an end of encoding and decoding and the validity of an encoded or decoded value in response to the given ordered rotate constant.

29. The system of claim 18, wherein the M6 block cipher system performs a single round during a single clock cycle.

30. The system of claim 18, wherein the M6 core comprises:

a first multiplexer which, in a first round operation, selects one of the input signals and a round output signal in response to a first control signal,

an M6 core controller generating a second operation start signal that indicates that a round operation is to be performed, the first control signal which instructs the first multiplexer to select a given input signal in the first round operation, the round output signal in another round operation and the validity signal, in response to the round number, the sub round number, and a first operation start signal,

a round key generator generating first and second round operation keys in response to a key signal used to create the two round operation keys, one key for each round of operation of the M6 core, and

a Pi function outputting the round number, the sub round number, and the round output signal obtained by performing a round operation on an output signal of the first multiplexer in response to the ordered rotate constants, the first and second round operation keys, and a mode selection signal to instruct the M6 core as to whether to encode or decode a given one of the input signals.

31. The system of claim 30, wherein the M6 core further receives a first operation start signal which instructs the M6 core to start operating, and the M6 core controller operates in response to the first operation start signal.

32. The system of claim 30, wherein the second operation start signal instructs the Pi function to start operating.

33. The system of claim 30, wherein

an output signal of the first multiplexer is divided into consecutive first and second data streams, and

the Pi function comprises:

a first basic operation device performing a basic operation using the first and second round operation keys, a constant “

1”

, and the first data stream,

a rotate function rotating an output signal of the first basic operation device a number of positions equal to the value of the ordered rotate constant, and

a second basic operation device performing the basic operation using an output signal of the rotate function, the output signal of the first basic operation device, and the second data stream, and

wherein the first basic operation device and the second basic operation device operate in response to the mode selection signal and the sub round number, the first and second basic operations selected from one of an addition operation, a subtraction operation and an operation of the locations of the basic operating devices.

34. The system of claim 33, wherein the first basic operation device performs the basic operation using:

the first round operation key and the first data stream L during a first sub round of each round,

the output signal of the second basic operation device and the constant “

1”

during each of a second sub round through a round before a final sub round of each round, and

the second round operation key and the output signal of the second basic operation device during the final sub round.

35. The system of claim 33, wherein the second basic operation device uses the second data stream during a final sub round of each round.

36. The system of claim 30, wherein the output signal of the first multiplexer contains 64 bits, and the first data stream and the second data stream includes 32 bits.

37. The system of claim 18, wherein the number of sub rounds is one of three, four or six sub rounds.

38. A method of encoding content and performing authenticating of a device, comprising:

selecting one or more rotate constants from a plurality of input rotate constants for output based on a selection signal configured to determine whether to encode content or to generate a random number and create an exchange key for device authentication,

ordering the selected rotate constants and one or both of a separate common rotate constant used to encode content and for device authentication, and a separate non-common rotate constant used when an output signal is not rotated, based on an ordering signal, and

generating, in an M6 core device, one or more of an output signal, a validity signal and at least one of a round number and a sub round number based on the ordered rotate constants and a plurality of input signals, wherein the ordering signal is generated based on the selection signal and one or both of the round number and sub round number.

39. The method of claim 38, wherein the input signals include a key signal, a operation start signal a mode selection signal and one of an input plain text signal or an input cipher text signal, and

the operation start signal instructs a start of operation,

the key signal is used to create two round operation keys, one key for each round of operation, and

the mode selection signal indicates whether to encode or decode a given one of the input signals.

40. The method of claim 39, wherein

if the given input signal is plain text, the mode selection signal represents an instruction to encode the input plain text signal, else

if the given input signal is cipher text, the mode selection signal represents an. instruction to decode the input cipher text signal.

41. The method of claim 38, wherein

the round number contains information on a present round operation,

the sub round number contains information on a present sub round operation performed in the present round,

the output signal is generated by encoding or decoding one of an input plain text or an input cipher text signal which are contained in the input signals to the M6 core, and

the validity signal indicates an end of encoding and decoding and the validity of an encoded or decoded value in response to the given ordered rotate constant.

42. An M6 block cipher system, comprising:

a rotate constant selector device selecting one or more rotate constants from a plurality of input rotate constants for output based on a selection signal input thereto,

a rotate constant ordering device ordering the selected rotate constants and a common rotate constant input thereto based on a received ordering signal,

an M6 core device generating one or more of an output signal, a validity signal and a round number based on the ordered rotate constants and a plurality of input signals, and

a rotate constant scheduler device outputting the ordering signal to the rotate constant ordering device in response to the selection signal and the round number,

wherein the system is configured to encode content and perform authentication of a device in accordance with the method of claim 38.

43. An M6 block cipher system that performs a plurality of round operations in order to authenticate devices for receiving/transmitting content and encode content, in which each of the plurality of round operations includes a plurality of sub round operations, the system comprising:

a rotate constant selector device selecting one or more rotate constants from a plurality of input rotate constants for output based on a selection signal input thereto,

a rotate constant ordering device ordering the selected rotate constants, a separately received common rotate constant and a separately received non- common rotate constant ordering the selected rotate constants, and outputting in response to the rotate constant selection signal,

an M6 core device generating one or more of an output signal, a validity signal, a round number and a sub round number based on the ordered rotate constants and a plurality of input signals, and

a rotate constant scheduler device outputting the ordering signal to the rotate constant ordering device in response to the selection signal, the round number and the sub round number,

wherein the system is configured to encode content and perform authentication of a device in accordance with the method of claim 39.