Data interaction method and device, and offline credit payment method and device

1. A computer-implemented method, comprising:

scanning, by a point-of-sale (POS) machine while offline, a two-dimensional code presented on a mobile computing device;

parsing, by the POS machine while offline, the two-dimensional code to identify a credit payment code for making a payment associated with the credit payment code;

decrypting, by the POS machine while offline, the credit payment code based on asymmetric key decryption to obtain a credit payment token, wherein at least part of the credit payment token is signed by a private key generated for an user account, and wherein the credit payment token comprises user identity information that is encrypted using a public key;

parsing, by the POS machine while offline, the credit payment token to obtain security content included in the credit payment token, wherein the security content comprises transaction information, the user identity information that is encrypted using the public key, and one or more random numbers corresponding to the credit payment token;

determining, by the POS machine while offline, that the payment associated with the credit payment code satisfies the security content, comprising determining that the one or more random numbers have not been included in previous payments and recorded by the POS machine;

in response to determining that the payment associated with the credit payment code satisfies the security content, accepting, by the POS machine, the payment offline; and

after accepting the payment offline, connecting, by the POS machine, to a server for verification and execution of the payment by the server at a predetermined time.

2. The computer-implemented method of claim 1 , wherein the transaction information includes at least one of a generation time of the credit payment token, a predetermined time duration the credit payment code is valid, payment account information, or authorized payee information.

3. The computer-implemented method of claim 2 , wherein the user identity information is encrypted using the public key different from a second public key that decrypts the credit payment token, and wherein the transaction information is encrypted using the private key, and wherein decrypting, by the POS machine while offline, the credit payment code based on the asymmetric key decryption to obtain the credit payment token comprises decrypting the transaction information using the second public key and keeping the user identity information encrypted.

4. The computer-implemented method of claim 1 , wherein determining that the payment associated with the credit payment code satisfies the security content further includes determining the credit payment code is obtained at a point-in-time within a predetermined time duration, and wherein the predetermined time duration begins at generation of the credit payment token.

5. The computer-implemented method of claim 1 , wherein the two- dimensional code is valid for offline payment use for a predetermined number of times.

6. The computer-implemented method of claim 1 , further comprising:

registering the POS machine to the server before obtaining the credit payment code; and

receiving the public key from the server for decrypting the credit payment code.

7. The computer-implemented method of claim 3 , further comprising

recording a credit payment after determining that the payment associated with the credit payment code satisfies the security content;

recording information associated with the decrypted transaction information and the encrypted user identity information; and

sending the recorded information to the server.

8. A non-transitory, computer-readable medium storing one or more instructions executable by a computer system to perform operations comprising:

scanning, by a point-of-sale (POS) machine while offline, a two-dimensional code presented on a mobile computing device;

parsing, by the POS machine while offline, the two-dimensional code to identify a credit payment code for making a payment associated with the credit payment code;

decrypting, by the POS machine while offline, the credit payment code based on asymmetric key decryption to obtain a credit payment token, wherein at least part of the credit payment token is signed by a private key generated for an user account, and wherein the credit payment token comprises user identity information that is encrypted using a public key;

parsing, by the POS machine while offline, the credit payment token to obtain security content included in the credit payment token, wherein the security content comprises transaction information, the user identity information that is encrypted using the public key, and one or more random numbers corresponding to the credit payment token;

determining, by the POS machine while offline, that the payment associated with the credit payment code satisfies the security content, comprising determining that the one or more random numbers have not been included in previous payments and recorded by the POS machine;

in response to determining that the payment associated with the credit payment code satisfies the security content, accepting, by the POS machine, the payment offline; and

after accepting the payment offline, connecting, by the POS machine, to a server for verification and execution of the payment by the server at a predetermined time.

9. The non-transitory, computer-readable medium of claim 8 , wherein the transaction information includes at least one of a generation time of the credit payment token, a predetermined time duration the credit payment code is valid, payment account information, or authorized payee information.

10. The non-transitory, computer-readable medium of claim 9 , wherein the user identity information is encrypted using the public key different from a second public key that decrypts the credit payment token, and wherein the transaction information is encrypted using the private key, and wherein decrypting, by the POS machine while offline, the credit payment code based on the asymmetric key decryption to obtain the credit payment token comprises decrypting the transaction information using the second public key and keeping the user identity information encrypted.

11. The non-transitory, computer-readable medium of claim 8 , wherein determining that the payment associated with the credit payment code satisfies the security content further includes determining the credit payment code is obtained at a point-in-time within a predetermined time duration, and wherein the predetermined time duration begins at generation of the credit payment token.

12. The non-transitory, computer-readable medium of claim 8 , wherein the two-dimensional code is valid for offline payment use for a predetermined number of times.

13. The non-transitory, computer-readable medium of claim 8 , wherein the operations further comprise:

registering the POS machine to the server before obtaining the credit payment code; and

receiving the public key from the server for decrypting the credit payment code.

14. The non-transitory, computer-readable medium of claim 10 , wherein the operations further comprise:

recording a credit payment after determining that the payment associated with the credit payment code satisfies the security content;

recording information associated with the decrypted transaction information and the encrypted user identity information; and

sending the recorded information to the server.

15. A computer-implemented system, comprising:

one or more computers; and

one or more computer memory devices interoperably coupled with the one or more computers and having tangible, non-transitory, machine-readable media storing one or more instructions that, when executed by the one or more computers, perform one or more operations comprising:

scanning, by a point-of-sale (POS) machine while offline, a two-dimensional code presented on a mobile computing device;

parsing, by the POS machine while offline, the two-dimensional code to identify a credit payment code for making a payment associated with the credit payment code;

decrypting, by the POS machine while offline, the credit payment code based on asymmetric key decryption to obtain a credit payment token, wherein at least part of the credit payment token is signed by a private key generated for an user account, and wherein the credit payment token comprises user identity information that is encrypted using a public key;

parsing, by the POS machine while offline, the credit payment token to obtain security content included in the credit payment token, wherein the security content comprises transaction information, the user identity information that is encrypted using the public key, and one or more random numbers corresponding to the credit payment token;

determining, by the POS machine while offline, that the payment associated with the credit payment code satisfies the security content, comprising determining that the one or more random numbers have not been included in previous payments and recorded by the POS machine;

in response to determining that the payment associated with the credit payment code satisfies the security content, accepting, by the POS machine, the payment offline; and

after accepting the payment offline, connecting, by the POS machine, to a server for verification and execution of the payment by the server at a predetermined time.

16. The computer-implemented system of claim 15 , wherein the transaction information includes at least one of a generation time of the credit payment token, a predetermined time duration the credit payment code is valid, payment account information, or authorized payee information.

17. The computer-implemented system of claim 16 , wherein the user identity information is encrypted using the public key different from a second public key that decrypts the credit payment token, and wherein the transaction information is encrypted using the private key.

18. The computer-implemented system of claim 15 , wherein determining that the payment associated with the credit payment code satisfies the security content further includes determining the credit payment code is obtained at a point-in-time within a predetermined time duration, and wherein the predetermined time duration begins at generation of the credit payment token.

19. The computer-implemented system of claim 15 , wherein the two-dimensional code is valid for offline payment use for a predetermined number of times.

20. The computer-implemented system of claim 15 , wherein the one or more operations further comprise:

registering the POS machine to the server before obtaining the credit payment code; and

receiving the public key from the server for decrypting the credit payment code.