Ensuring information fairness and input privacy using a blockchain in a competitive scenario governed by a smart contract

1. A method, comprising:

initializing a smart contract and appending it to a blockchain;

registering each of a plurality of participants as a party to the smart contract;

generating a system-wide public/private key pair and storing the generated system-wide public key in a genesis block of the blockchain;

calculating a unique share of the system-wide private key for each participant who provided a confidential input commitment, and encrypting the unique share using the public key of one of the participants;

sending each of the encrypted unique shares to the participant having the private key corresponding to the public key used to encrypt the share;

opening a bidding window for the plurality of participants and begin counting block events that occur on the blockchain;

receiving from at least some of the participants an encrypted confidential input commitment during the open bidding window, each encrypted confidential input being encrypted with the system-wide public key;

terminating, via the smart contract, the open bidding window when the counting reaches a predetermined threshold and denying any other encrypted input commitments received after the termination of the open bidding window via the smart contract;

appending the encrypted input commitments to the blockchain;

recovering the private key based on decrypted unique shares of the system-wide private key that are shared by a predetermined number of participants;

decrypting the encrypted input commitments based on the recovered private key and storing the decrypted input commitments on the blockchain;

executing, by the smart contract, at least one business rule using the decrypted input commitments to obtain a business rule result; and

identifying a prevailing participant based at least in part on the business rule result.

2. The method of claim 1 , wherein:

parameters for initializing the smart contract are obtained from a dealer;

the terms of the smart contract pertain to the plurality of participants and the dealer, each of which controls their own computing environment; and

the blockchain is implemented at least in part on the computing environments.

3. The method of claim 1 , wherein the registering of each of the plurality of participants includes:

receiving identification information of a participant;

obtaining a public key of a public/private key pair for which the participant has the corresponding private key; and

storing the public key in association with identification information of the participant.

4. The method of claim 1 , further comprising:

generating a message including information for identifying the prevailing participant of a bidding process;

encrypting the message using the system-wide public key; and

making the encrypted message available to the plurality of participants.

5. The method of claim 1 , wherein the recovering comprises:

receiving decrypted unique shares from at least a predetermined threshold number of the plurality of participants using their respective private keys; and

combining the decrypted unique shares to reconstruct the system-wide private key.

6. The method of claim 5 , further comprising:

calculating a string PROOF D that can be used to prove the shares of the system-wide private key are valid, sending the string PROOF D with each of the encrypted shares, and appending the string PROOF D to the blockchain.

7. A system, comprising:

a processor configured to:

initialize a smart contract and append it to a blockchain;

register each of a plurality of participants as a party to the smart contract;

generate a system-wide public/private key pair and storing the generated system- wide public key in a genesis block of the blockchain;

calculate a unique share of the system-wide private key for each participant who provided a confidential input commitment, and encrypting the unique share using the public key of one of the participants;

send each of the encrypted unique shares to the participant having the private key corresponding to the public key used to encrypt the share;

open a bidding window for the plurality of participants and begin counting block events that occur on the blockchain;

receive from at least some of the participants an encrypted confidential input commitment during the open bidding window, each encrypted confidential input being encrypted with the system-wide public key;

terminate, via the smart contract, the open bidding window when the counting reaches a predetermined threshold and deny any other encrypted input commitments received after the termination of the open bidding window via the smart contract;

append the encrypted input commitments to the blockchain;

recover the private key based on decrypted unique shares of the system-wide private key that are shared by a predetermined number of participants;

decrypt the encrypted input commitments based on the recovered private key and storing the decrypted input commitments on the blockchain;

execute, by the smart contract, at least one business rule based on the decrypted input commitments to obtain a business rule result; and

identify a prevailing participant based at least in part on the business rule result.

8. The system of claim 7 , wherein:

parameters to initialize the smart contract are obtained from a dealer;

terms of the smart contract pertain to the plurality of participants and the dealer, each of which controls their own computing environment; and

the blockchain is implemented at least in part on the computing environments.

9. The system of claim 7 , wherein the processor is further configured to:

receive identification information of a participant;

obtain a public key of a public/private key pair for which the participant has the private key; and

store the public key in association with identification information of the participant.

10. The system of claim 7 , wherein the processor is further configured to:

generate a message that includes information that identifies a prevailing participant of a bidding process;

encrypt the message based on the system-wide public key; and

make the encrypted message available to the plurality of participants.

11. The system of claim 7 , wherein the processor is further configured to:

receive decrypted unique shares from at least a predetermined threshold number of the plurality of participants based on their respective private keys; and

combine the decrypted unique shares to reconstruct the system-wide private key.

12. The system of claim 11 , wherein the processor is further configured to:

calculate a string PROOF D that can be used to prove the shares of the system-wide private key are valid, send the string PROOF D with each of the encrypted shares, and append the string PROOF D to the blockchain.

13. A computer program product comprising a non-transitory computer readable medium and instructions stored on the non-transitory computer readable medium which when executed by a processor cause a computer to perform a method comprising:

initializing a smart contract and appending it to a blockchain;

registering each of a plurality of participants as a party to the smart contract;

generating a system-wide public/private key pair and storing the generated system-wide public key in a genesis block of the blockchain;

calculating a unique share of the system-wide private key for each participant who provided a confidential input commitment, and encrypting the unique share using the public key of one of the participants;

sending each of the encrypted unique shares to the participant having the private key corresponding to the public key used to encrypt the share;

opening a bidding window for the plurality of participants and begin counting block events that occur on the blockchain;

receiving from at least some of the participants an encrypted confidential input commitment during the open bidding window, each encrypted confidential input being encrypted with the system-wide public key;

terminating, via the smart contract, the open bidding window when the counting reaches a predetermined threshold and denying any other encrypted input commitments received after the termination of the open bidding window via the smart contract;

appending the encrypted input commitments to the blockchain;

recovering the private key based on decrypted unique shares of the system-wide private key that are shared by a predetermined number of participants;

decrypting the encrypted input commitments based on the recovered private key and storing the decrypted input commitments on the blockchain;

executing by the smart contract, at least one business rule using the decrypted input commitments to obtain a business rule result.

14. The computer program product of claim 13 , wherein:

parameters for initializing the smart contract are obtained from a dealer;

the terms of the smart contract pertain to the plurality of participants and the dealer, each of which controls their own computing environment; and

the blockchain is implemented at least in part on the computing environments.

15. The computer program product of claim 13 , wherein the registering of each of the plurality of participants includes:

receiving identification information of a participant;

obtaining a public key of a public/private key pair for which the participant has the corresponding private key; and

storing the public key in association with identification information of the participant.

16. The computer program product of claim 13 , wherein the method further comprises:

generating a message including information for identifying a prevailing participant of a bidding process;

encrypting the message using the system-wide public key; and

making the encrypted message available to the plurality of participants.

17. The computer program product of claim 13 , wherein the recovering comprises:

receiving decrypted unique shares from at least a predetermined threshold number of the plurality of participants using their respective private keys; and

combining the decrypted shares to reconstruct the system-wide private key.