Method and apparatus for obtaining input of secure multiparty computation protocol
Privacy protection methods, systems, and apparatus, including computer programs encoded on computer storage media, are provided. One of the methods is performed by a second computing device and includes: receiving a data request for object data from a first computing device, wherein the object data is associated with an object and is stored in the second computing device; performing encryption of the object data using a public key associated with the object based on the data request to generate a first ciphertext; obtaining verification data based on the first ciphertext for verifying whether a ciphertext to be verified corresponds to the object data; and sending the verification data to the first computing device for the first computing device to execute a cryptography protocol with a third computing device based on the verification data.
1. A method, comprising:
obtaining, at a first computing device associated with an authorized organization, a public key associated with an object;
receiving, at the first computing device from a second computing device, a data request for object data associated with the object, wherein the object data is stored in the first computing device;
generating, at the first computing device, a random number;
in response to receiving the data request, performing homomorphic encryption of the object data using the public key and the random number to generate a first ciphertext;
generating, at the first computing device, a digital signature of the authorized organization that endorses the first ciphertext or endorses a hash value of the first ciphertext;
storing in a storage location of a blockchain, using the first computing device, (1) the digital signature and (2) the first ciphertext or the hash value of the first ciphertext;
obtaining, at the first computing device, verification data for verifying whether an unverified ciphertext corresponds to the object data, the verification data comprising the storage location of the blockchain;
sending the random number to the second computing device for the second computing device to also generate the first ciphertext by performing the homomorphic encryption of the object data using the public key and the random number; and
sending the verification data to the second computing device for the second computing device to execute a secure multiparty computation protocol for the object data with a third computing device based on the verification data.
2. The method of claim 1 , further comprising: sending the first ciphertext to the second computing device.
3. The method of claim 1 , wherein the digital signature of the authorized organization endorses the first ciphertext, wherein the method comprises: storing in the storage location of the blockchain, using the first computing device, the digital signature and the first ciphertext.
4. The method of claim 1 , wherein the digital signature of the authorized organization endorses the hash value of the first ciphertext, wherein the method further comprises:
generating, at the first computing device, the hash value based on the first ciphertext; and
storing in the storage location of the blockchain, using the first computing device, the digital signature and the hash value of the first ciphertext.
5. The method of claim 1 , wherein the verification data comprises the digital signature.
6. The method of claim 1 , wherein: sending the verification data to the second computing device comprises: causing the third computing device to verify, based on the verification data, that the unverified ciphertext is equivalent to the first ciphertext and to determine the first ciphertext as an input to the secure multiparty computation protocol in response to determining that the first ciphertext corresponds to the object data.
7. A non-transitory computer-readable storage medium storing instructions that, when executed by a processor, cause the processor to perform a method comprising:
obtaining, at a first computing device associated with an authorized organization, a public key associated with an object;
receiving, at the first computing device from a second computing device, a data request for object data associated with the object, wherein the object data is stored in the first computing device;
generating, at the first computing device, a random number;
in response to receiving the data request, performing homomorphic encryption of the object data using the public key and the random number to generate a first ciphertext;
generating, at the first computing device, a digital signature of the authorized organization that endorses the first ciphertext or endorses a hash value of the first ciphertext;
storing in a storage location of a blockchain, using the first computing device, (1) the digital signature and (2) the first ciphertext or the hash value of the first ciphertext;
obtaining, at the first computing device, verification data for verifying whether an unverified ciphertext corresponds to the object data, the verification data comprising the storage location of the blockchain;
sending the random number to the second computing device for the second computing device to also generate the first ciphertext by performing the homomorphic encryption of the object data using the public key and the random number; and
sending the verification data to the second computing device for the second computing device to execute a secure multiparty computation protocol for the object data with a third computing device based on the verification data.
8. The non-transitory computer-readable storage medium of claim 7 , wherein the method further comprises: sending the first ciphertext to the second computing device.
9. The non-transitory computer-readable storage medium of claim 7 , wherein the digital signature of the authorized organization endorses the first ciphertext, wherein the method comprises: storing in the storage location of the blockchain, using the first computing device, the digital signature and the first ciphertext.
10. The non-transitory computer-readable storage medium of claim 7 , wherein the digital signature of the authorized organization endorses the hash value of the first ciphertext, wherein the method further comprises:
generating, at the first computing device, the hash value based on the first ciphertext; and
storing in the storage location of the blockchain, using the first computing device, the digital signature and the hash value of the first ciphertext.
11. The non-transitory computer-readable storage medium of claim 7 , wherein the verification data comprises the digital signature.
12. A system, comprising:
a processor; and
a non-transitory computer-readable storage medium storing instructions that, when executed by the processor, cause the processor to perform a method comprising:
obtaining, at a first computing device associated with an authorized organization, a public key associated with an object;
receiving, at the first computing device from a second computing device, a data request for object data associated with the object, wherein the object data is stored in the first computing device;
generating, at the first computing device, a random number;
in response to receiving the data request, performing homomorphic encryption of the object data using the public key and the random number to generate a first ciphertext;
generating, at the first computing device, a digital signature of the authorized organization that endorses the first ciphertext or endorses a hash value of the first ciphertext;
storing in a storage location of a blockchain, using the first computing device, (1) the digital signature and (2) the first ciphertext or the hash value of the first ciphertext;
obtaining, at the first computing device, verification data for verifying whether an unverified ciphertext corresponds to the object data, the verification data comprising the storage location of the blockchain;
sending the random number to the second computing device for the second computing device to also generate the first ciphertext by performing the homomorphic encryption of the object data using the public key and the random number; and
sending the verification data to the second computing device for the second computing device to execute a secure multiparty computation protocol for the object data with a third computing device based on the verification data.
13. The system of claim 12 , wherein the method further comprises: sending the first ciphertext to the second computing device.
14. The system of claim 12 , wherein the digital signature of the authorized organization endorses the first ciphertext, wherein the method comprises: storing in the storage location of the blockchain, using the first computing device, the digital signature and the first ciphertext.
15. The system of claim 12 , wherein the digital signature of the authorized organization endorses the hash value of the first ciphertext, wherein the method further comprises:
generating, at the first computing device, the hash value based on the first ciphertext; and
storing in the storage location of the blockchain, using the first computing device, the digital signature and the hash value of the first ciphertext.
16. The system of claim 12 , wherein the verification data comprises the digital signature.