System and method for detecting replay attack

1. A computer-implemented method for detecting replay attack, comprising:

obtaining, from a user terminal, at least one transaction for adding to a blockchain;

adding a timestamp to the at least one transaction to obtain at least one candidate transaction for adding to the blockchain, wherein the at least one candidate transaction comprises the timestamp and transaction information;

determining a hash value based at least on the timestamp and the transaction information, the hash value serving as an identification of the candidate transaction;

verifying if the timestamp is within a validation range and if the identification of the candidate transaction exists in an identification database, the identification database comprising a plurality of identifications within the validation range; and

in response to determining that the timestamp is within the validation range and the identification does not exist in the identification database, determining that the candidate transaction is not associated with a replay attack.

2. A computer-implemented method for detecting replay attack, comprising:

obtaining, from a user terminal, at least one transaction for adding to a blockchain;

adding a timestamp to the at least one transaction to obtain at least one candidate transaction for adding to the blockchain, wherein the candidate transaction comprises the timestamp, transaction information, and a hash value determined based at least on the timestamp and the transaction information, the hash value serving as an identification;

verifying the identification by verifying the hash value based at least on the timestamp and the transaction information;

verifying if the timestamp is within a validation range and if the identification of the candidate transaction exists in an identification database, the identification database comprising a plurality of identifications within the validation range; and

in response to determining that the timestamp is within the validation range and the identification does not exist in the identification database, determining that the candidate transaction is not associated with a replay attack.

3. The method of claim 1 , further comprising:

in response to determining that the timestamp is within the validation range and the identification does not exist in the identification database, adding the identification to the identification database.

4. The method of claim 1 , further comprising:

in response to determining that the timestamp is within the validation range and the identification does not exist in the identification database, adding the candidate transaction to a cache for storing candidate transactions.

5. The method of claim 1 , further comprising:

in response to determining that the timestamp is not within the validation range, returning an error message to a computing device that submitted the candidate transaction.

6. The method of claim 1 , further comprising:

in response to determining that the identification exists in the identification database, determining that the candidate transaction is associated with the replay attack.

7. The method of claim 1 , further comprising:

performing consensus verification, wherein the candidate transaction is included in the consensus verification if the candidate transaction is determined not to be associated with the replay attack.

8. The method of claim 7 , further comprising:

synchronizing the identification database with one or more blockchain nodes;

verifying if the timestamp is within the validation range and if the identification of the candidate transaction exists in the synchronized identification database;

if the timestamp is within the validation range and the identification does not exist in the synchronized identification database, determining that the candidate transaction is not associated with the replay attack; and

if the identification exists in the synchronized identification database, determining that the candidate transaction is associated with the replay attack.

9. The method of claim 1 , before obtaining the at least one candidate transaction, further comprising:

synchronizing the identification database with one or more blockchain nodes.

10. The method of claim 1 , wherein:

the identification database comprises information of transactions with timestamps within a recent time period corresponding to the validation range.

11. The method of claim 1 , wherein:

the validation range is based on another timestamp of a latest block of the blockchain; and

the validation range is included in a genesis block of the blockchain.

12. A system for detecting replay attack, comprising one or more processors and one or more non-transitory computer-readable memories coupled to the one or more processors and configured with instructions executable by the one or more processors to cause the system to perform operations comprising:

obtaining, from a user terminal, at least one transaction for adding to a blockchain;

adding a timestamp to the at least one transaction to obtain at least one candidate transaction for adding to the blockchain, wherein the at least one candidate transaction comprises the timestamp and transaction information;

determining a hash value based at least on the timestamp and the transaction information, the hash value serving as an identification of the candidate transaction;

verifying if the timestamp is within a validation range and if the identification of the candidate transaction exists in an identification database, the identification database comprising a plurality of identifications within the validation range; and

in response to determining that the timestamp is within the validation range and the identification does not exist in the identification database, determining that the candidate transaction is not associated with a replay attack.

13. The system of claim 12 , wherein the operations further comprise:

in response to determining that the timestamp is within the validation range and the identification does not exist in the identification database, adding the identification to the identification database.

14. A non-transitory computer-readable storage medium configured with instructions executable by one or more processors to cause the one or more processors to perform operations comprising:

obtaining, from a user terminal, at least one transaction for adding to a blockchain;

adding a timestamp to the at least one transaction to obtain at least one candidate transaction for adding to the blockchain, wherein the at least one candidate transaction comprises the timestamp and transaction information;

determining a hash value based at least on the timestamp and the transaction information, the hash value serving as an identification of the candidate transaction;

verifying if the timestamp is within a validation range and if the identification of the candidate transaction exists in an identification database, the identification database comprising a plurality of identifications within the validation range; and

in response to determining that the timestamp is within the validation range and the identification does not exist in the identification database, determining that the candidate transaction is not associated with a replay attack.

15. A non-transitory computer-readable storage medium configured with instructions executable by one or more processors to cause the one or more processors to perform operations comprising:

obtaining, from a user terminal, at least one transaction for adding to a blockchain;

adding a timestamp to the at least one transaction to obtain at least one candidate transaction for adding to the blockchain, wherein the candidate transaction comprises the timestamp, transaction information, and a hash value determined based at least on the timestamp and the transaction information, the hash value serving as an identification;

verifying the identification by verifying the hash value based at least on the timestamp and the transaction information;

verifying if the timestamp is within a validation range and if the identification of the candidate transaction exists in an identification database, the identification database comprising a plurality of identifications within the validation range; and

in response to determining that the timestamp is within the validation range and the identification does not exist in the identification database, determining that the candidate transaction is not associated with a replay attack.

16. The storage medium of claim 14 , wherein the operations further comprise:

in response to determining that the timestamp is within the validation range and the identification does not exist in the identification database, adding the identification to the identification database.