Processor authentication method through signed instruction

1. A method, comprising:

decoding a first opcode into a decoded instruction and a plurality of decoded operands;

receiving, on a first terminal of an arithmetic and logic unit of a processor, a decoded operand of the plurality of decoded operands;

generating a first instruction by combining the decoded instruction with signature data, the signature data being an output data of the arithmetic and logic unit prior to the generating the first instruction;

receiving, on a second terminal of the arithmetic and logic unit, the first instruction; and

authenticating the processor based on a result of the arithmetic and logic unit processing the first instruction.

2. The method of claim 1 , wherein the output data of the arithmetic and logic unit is stored in a register bank, the register bank configured to operate as one of a linear feedback shift register and a shift register where last stored information is the first information to be removed.

3. The method of claim 2 , wherein the register bank is configured to generate the signature data based on the output data and wherein the output data includes at least one calculation result of the arithmetic and logic unit prior to the generating the first instruction.

4. The method of claim 3 , wherein the output data of the arithmetic and logic unit is a processing result of the arithmetic and logic unit with respect to a second opcode.

5. The method of claim 1 , wherein the generating the first instruction is conducted by a combination circuit.

6. The method of claim 1 , comprising processing, by the arithmetic and logic unit, the first instruction with respect to the decoded operand of the plurality of decoded operands.

7. The method of claim 1 , wherein the signature data also corresponds to a second opcode executed by the processor prior to the generating the first instruction.

8. A processor, comprising:

a combination circuit that operates to generate a first instruction by combining a second instruction of a first opcode with signature data; and

an arithmetic and logic unit having a first terminal and a second terminal, the first terminal being configured to receive a first operand of the first opcode, and the second terminal being configured to receive the first instruction;

wherein the signature data is a processing result of the arithmetic and logic unit with respect to a second opcode that is received by the processor before the first opcode; and

wherein the processor is configured to be authenticated based on a result of the arithmetic and logic unit processing the first instruction.

9. The processor of claim 8 , wherein the combination circuit is configured to be controlled by an operand of the first opcode.

10. The processor of claim 8 , wherein the combination circuit is configured to combine the second instruction with at least a part of the second opcode.

11. The processor of claim 8 , further comprising a result register bank configured to store the processing result of the arithmetic and logic unit with respect to the second opcode.

12. The processor of claim 8 , wherein the arithmetic and logic unit is configured to process the first instruction received on its second terminal with respect to the first operand received on its first terminal.

13. The processor of claim 8 , wherein the combination circuit operates to generate the first instruction by combining the second instruction of the first opcode with at least a part of a third opcode that has already been processed by the arithmetic and logic unit.

14. The processor of claim 8 , further comprising a decoding circuit configured to decode the first opcode into the second instruction and a plurality of operands including the first operand.

15. The processor of claim 14 , further comprising a multiplexer configured to receive the plurality of operands, to select the first operand among the plurality of operands, and to deliver the first operand to the first terminal of the arithmetic and logic unit.

16. An integrated circuit, comprising:

a decoding circuitry that operates to decode a first opcode into a decoded instruction and a plurality of decoded operands;

a multiplexer circuitry that operates to select a first decoded operand from the plurality of decoded operands;

a combination circuitry that operates to generate a signed instruction by combining the decoded instruction and signature data; and

an arithmetic and logic circuitry that operates to calculate a first result based on the first decoded operand and the signed instruction;

wherein the signature data includes a second result calculated by the arithmetic and logic circuitry prior to the first result; and

wherein the first result is configured to authenticate the integrated circuit.

17. The integrated circuit of claim 16 , wherein the second result is calculated by the arithmetic and logic circuitry with respect to a second opcode that is different from the first opcode.

18. The integrated circuit of claim 16 , wherein the multiplexer circuitry operates to deliver a second decoded operand of the plurality of decoded operands to the combination circuitry, the second decoded operand controlling the combination circuitry in generating the signed instruction.

19. The integrated circuit of claim 16 , further comprising a register bank configured to store the second result.

20. The integrated circuit of claim 19 , wherein the register bank is configured to store a second opcode that is different from the first opcode and is configured to generate the signature data at least partially based on the second opcode.