System and method for information protection

1. A non-transitory computer-readable storage medium of a recipient node associated with a recipient of a transaction, the storage medium storing instructions that, when executed by a processor, cause the processor to perform operations comprising:

obtaining a transaction amount t of the transaction from a sender node associated with a sender of the transaction, a transaction blinding factor r_t, and a transaction commitment value T;

verifying the transaction by verifying the obtained transaction commitment value T based on the obtained transaction amount t and the obtained transaction blinding factor r_t;

in response to successfully verifying the transaction, generating an encrypted combination by encrypting the transaction blinding factor r_t and the transaction amount t with a public key PK_B of the recipient; and

transmitting the encrypted combination to the sender node.

2. The storage medium of claim 1 , wherein encrypting the transaction blinding factor r_t and the transaction amount t with the public key PK_B of the recipient comprises:

encrypting a concatenation of the transaction blinding factor r_t and the transaction amount t with the public key PK_B of the recipient.

3. The storage medium of claim 1 , wherein:

the transaction commitment value T is generated by the sender node according to a commitment scheme; and

the commitment scheme comprises a Pedersen commitment based at least on the transaction blinding factor r_t and with the transaction amount t being a committed value.

4. The storage medium of claim 3 , wherein verifying the transaction comprises:

in response to determining that the obtained transaction commitment value T does not match a result of committing the transaction amount t based on the transaction blinding factor r_t according to the commitment scheme, rejecting the transaction; or

in response to determining that the obtained transaction commitment value T matches the result of committing the transaction amount t based on the transaction blinding factor r_t according to the commitment scheme, approving the transaction.

5. The storage medium of claim 4 , wherein approving the transaction comprises:

generating a recipient signature SIGB by signing the transaction with a private key SK_B of the recipient.

6. The storage medium of claim 5 , wherein the operations further comprise:

transmitting the recipient signature SIGB to the sender node.

7. The storage medium of claim 5 , wherein:

the recipient signature SIGB is added to an updated version of the transaction before the updated version of the transaction is added to a blockchain.

8. A computer-implemented method for information protection, performed by a recipient node associated with a recipient of a transaction, comprising:

obtaining a transaction amount t of the transaction from a sender node associated with a sender of the transaction, a transaction blinding factor r_t, and a transaction commitment value T;

verifying the transaction by verifying the obtained transaction commitment value T based on the obtained transaction amount t and the obtained transaction blinding factor r_t;

in response to successfully verifying the transaction, generating an encrypted combination by encrypting the transaction blinding factor r_t and the transaction amount t with a public key PK_B of the recipient; and

transmitting the encrypted combination to the sender node.

9. The method of claim 8 , wherein encrypting the transaction blinding factor r_t and the transaction amount t with the public key PK_B of the recipient comprises:

encrypting a concatenation of the transaction blinding factor r_t and the transaction amount t with the public key PK_B of the recipient.

10. The method of claim 8 , wherein:

the transaction commitment value T is generated by the sender node according to a commitment scheme; and

the commitment scheme comprises a Pedersen commitment based at least on the transaction blinding factor r_t and with the transaction amount t being a committed value.

11. The method of claim 10 , wherein verifying the transaction comprises:

in response to determining that the obtained transaction commitment value T does not match a result of committing the transaction amount t based on the transaction blinding factor r_t according to the commitment scheme, rejecting the transaction; or

in response to determining that the obtained transaction commitment value T matches the result of committing the transaction amount t based on the transaction blinding factor r_t according to the commitment scheme, approving the transaction.

12. The method of claim 11 , wherein approving the transaction comprises:

generating a recipient signature SIGB by signing the transaction with a private key SK_B of the recipient.

13. The method of claim 12 , further comprising:

transmitting the recipient signature SIGB to the sender node.

14. The method of claim 12 , wherein:

the recipient signature SIGB is added to an updated version of the transaction before the updated version of the transaction is added to a blockchain.

15. A system comprising a processor and a non-transitory computer-readable storage medium of a recipient node associated with a recipient of a transaction, the storage medium storing instructions that, when executed by the processor, cause the processor to perform operations comprising:

obtaining a transaction amount t of the transaction from a sender node associated with a sender of the transaction, a transaction blinding factor r_t, and a transaction commitment value T;

verifying the transaction by verifying the obtained transaction commitment value T based on the obtained transaction amount t and the obtained transaction blinding factor r_t;

in response to successfully verifying the transaction, generating an encrypted combination by encrypting the transaction blinding factor r_t and the transaction amount t with a public key PK_B of the recipient; and

transmitting the encrypted combination to the sender node.

16. The system of claim 15 , wherein encrypting the transaction blinding factor r_t and the transaction amount t with the public key PK_B of the recipient comprises:

encrypting a concatenation of the transaction blinding factor r_t and the transaction amount t with the public key PK_B of the recipient.

17. The system of claim 15 , wherein:

the transaction commitment value T is generated by the sender node according to a commitment scheme; and

the commitment scheme comprises a Pedersen commitment based at least on the transaction blinding factor r_t and with the transaction amount t being a committed value.

18. The system of claim 17 , wherein verifying the transaction comprises:

in response to determining that the obtained transaction commitment value T does not match a result of committing the transaction amount t based on the transaction blinding factor r_t according to the commitment scheme, rejecting the transaction; or

in response to determining that the obtained transaction commitment value T matches the result of committing the transaction amount t based on the transaction blinding factor r_t according to the commitment scheme, approving the transaction.

19. The system of claim 18 , wherein approving the transaction comprises:

generating a recipient signature SIGB by signing the transaction with a private key SK_B of the recipient.

20. The system of claim 19 , wherein the operations further comprise:

transmitting the recipient signature SIGB to the sender node.