Integrity of communications between blockchain networks and external data sources

1. A computer-implemented method for retrieving data from a data source that is external to a blockchain network, the method comprising:

generating, by a user computing device, a request for data from the data source, the request comprising a first portion and a second portion, the first portion comprising plaintext data and the second portion comprising encrypted data, the encrypted data comprising a concatenated data element encrypted using a public key of a relay system component, the concatenated data element comprising access data that is concatenated to a first hash value of the plaintext data;

transmitting, by the user computing device, the request to the relay system component through the blockchain network; and

receiving, by the user computing device, result data from the relay system component through the blockchain network, the result data being retrieved using the access data and digitally signed using a private key of the relay system component.

2. The computer-implemented method of claim 1 , wherein the request is configured to cause the relay system component to:

decrypt the encrypted data using a private key of the relay system component to provide the first hash value;

calculate a second hash value based on the plaintext data included in the request;

compare the first hash value to the second hash value to determine that the first hash value is identical to the second hash value; and

transmit a result responsive to determining that the first hash value is identical to the second hash value, the result comprising the result data.

3. The computer-implemented method of claim 2 , wherein the result further comprises a third hash value, and wherein the third hash value is generated based on the result data.

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

verifying, by the user computing device, an integrity of the result based on the public key of the relay system component, a digital signature of the result, and the third hash value.

5. The method of claim 1 , wherein the relay system component comprises a relay system node that receives the request from a relay system smart contract executing within the blockchain network.

6. The method of claim 1 , wherein the plaintext data comprises a uniform resource locator (URL) of the data source.

7. The method of claim 1 , wherein the relay system component executes a trusted execution environment (TEE), and wherein the private key and the public key of the relay system component are provisioned during an attestation process of the TEE.

8. A non-transitory, computer-readable storage medium storing instructions executable by a computer system and that upon such execution cause the computer system to perform operations for retrieving data from a data source that is external to a blockchain network, the operations comprising:

generating a request for data from the data source, the request comprising a first portion and a second portion, the first portion comprising plaintext data and the second portion comprising encrypted data, the encrypted data comprising a concatenated data element encrypted using a public key of a relay system component, the concatenated data element comprising access data that is concatenated to a first hash value of the plaintext data;

transmitting the request to the relay system component through the blockchain network; and

receiving result data from the relay system component through the blockchain network, the result data being retrieved using the access data and digitally signed using a private key of the relay system component.

9. The non-transitory, computer-readable storage medium of claim 8 , wherein the request is configured to cause the relay system component to:

decrypt the encrypted data using a private key of the relay system component to provide the first hash value;

calculate a second hash value based on the plaintext data included in the request;

compare the first hash value to the second hash value to determine that the first hash value is identical to the second hash value; and

transmit a result responsive to determining that the first hash value is identical to the second hash value, the result comprising the result data.

10. The non-transitory, computer-readable storage medium of claim 9 , wherein the result further comprises a third hash value, and wherein the third hash value is generated based on the result data.

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

verifying an integrity of the result based on the public key of the relay system component, a digital signature of the result, and the third hash value.

12. The non-transitory, computer-readable storage medium of claim 8 , wherein the relay system component comprises a relay system node that receives the request from a relay system smart contract executing within the blockchain network.

13. The non-transitory, computer-readable storage medium of claim 8 , wherein the plaintext data comprises a uniform resource locator (URL) of the data source.

14. The non-transitory, computer-readable storage medium of claim 8 , wherein the relay system component executes a trusted execution environment (TEE), and wherein the private key and the public key of the relay system component are provisioned during an attestation process of the TEE.

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 instructions that, when executed by the one or more computers, cause the one or more computers to perform operations for retrieving data from a data source that is external to a blockchain network, the operations comprising:

generating a request for data from the data source, the request comprising a first portion and a second portion, the first portion comprising plaintext data and the second portion comprising encrypted data, the encrypted data comprising a concatenated data element encrypted using a public key of a relay system component, the concatenated data element comprising access data that is concatenated to a first hash value of the plaintext data;

transmitting the request to the relay system component through the blockchain network; and

receiving result data from the relay system component through the blockchain network, the result data being retrieved using the access data and digitally signed using a private key of the relay system component.

16. The computer-implemented system of claim 15 , wherein the request is configured to cause the relay system component to:

decrypt the encrypted data using a private key of the relay system component to provide the first hash value;

calculate a second hash value based on the plaintext data included in the request;

compare the first hash value to the second hash value to determine that the first hash value is identical to the second hash value; and

transmit a result responsive to determining that the first hash value is identical to the second hash value, the result comprising the result data.

17. The computer-implemented system of claim 16 , wherein the result further comprises a third hash value, and wherein the third hash value is generated based on the result data.

18. The computer-implemented system of claim 17 , wherein the operations further comprise:

verifying an integrity of the result based on the public key of the relay system component, a digital signature of the result, and the third hash value.

19. The computer-implemented system of claim 15 , wherein the relay system component comprises a relay system node that receives the request from a relay system smart contract executing within the blockchain network.

20. The computer-implemented system of claim 15 , wherein the plaintext data comprises a uniform resource locator (URL) of the data source.