Key data processing method and apparatus, and server

1. A computer-implemented method for managing shared ownership in a block chain network, the method comprising:

obtaining a parent cryptographic key associated with a blockchain object and one or more assets owned by a number of parties; and

responsive to detecting a change in the number of parties that own the one or more assets,

generating N child cryptographic keys based on the parent cryptographic key by applying a predetermined algorithm to the parent cryptographic key, wherein N is an integer greater than or equal to 2 corresponding to a current number of parties that own the one or more assets;

wherein applying the predetermined algorithm to the parent cryptographic key comprises generating N−1 random numbers having bit-lengths equal to a bit-length of the parent cryptographic key and performing a series of bitwise XOR operations between the parent cryptographic key and a first random number of the N−1 random numbers to generate a first output then sequentially performing XOR operations between an output of a previous XOR operation and a random number not previously used to generate an XOR child cryptographic key and obtain the N child cryptographic keys, wherein the N child cryptographic keys include the XOR child cryptographic key and the N−1 random numbers;

receiving a plurality of cryptographic keys comprising the XOR child cryptographic key and the N−1 random numbers;

determining a number of the received plurality of cryptographic keys is equal to the number of parties sharing control over the blockchain object; and

in response to determining that the number of the received plurality of cryptographic keys is equal to the number of parties sharing control over the blockchain object, reconstructing the parent cryptographic key by performing a series of bitwise XOR operations, sequentially, on the received plurality of cryptographic keys and referencing third party auxiliary data.

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

transmitting the N child cryptographic keys to corresponding parties; and

deleting the parent cryptographic key.

3. The computer-implemented method of claim 1 , wherein applying the predetermined algorithm to the parent cryptographic key comprises:

modifying the parent cryptographic key based on a randomly generated character string.

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

obtaining a parent cryptographic key associated with a blockchain object and one or more assets owned by a number of parties; and

responsive to detecting a change in the number of parties that own the one or more assets,

generating N child cryptographic keys based on the parent cryptographic key by applying a predetermined algorithm to the parent cryptographic key, wherein N is an integer greater than or equal to 2 corresponding to a current number of parties that own the one or more assets;

wherein applying the predetermined algorithm to the parent cryptographic key comprises generating N−1 random numbers having bit-lengths equal to a bit-length of the parent cryptographic key and performing a series of bitwise XOR operations between the parent cryptographic key and a first random number of the N−1 random numbers to generate a first output then sequentially performing XOR operations between an output of a previous XOR operation and a random number not previously used to generate an XOR child cryptographic key and obtain the N child cryptographic keys, wherein the N child cryptographic keys include the XOR child cryptographic key and the N−1 random numbers;

receiving a plurality of cryptographic keys comprising the XOR child cryptographic key and the N−1 random numbers;

determining a number of the received plurality of cryptographic keys is equal to the number of parties sharing control over the blockchain object; and

in response to determining that the number of the received plurality of cryptographic keys is equal to the number of parties sharing control over the blockchain object, reconstructing the parent cryptographic key by performing a series of bitwise XOR operations, sequentially, on the received plurality of cryptographic keys and referencing third party auxiliary data.

5. The non-transitory, computer-readable medium of claim 4 , wherein the operations further comprise:

transmitting the N child cryptographic keys to corresponding parties; and

deleting the parent cryptographic key.

6. The non-transitory, computer-readable medium of claim 4 , wherein applying the predetermined algorithm to the parent cryptographic key comprises:

modifying the parent cryptographic key based on a randomly generated character string.

7. 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:

obtaining a parent cryptographic key associated with a blockchain object and one or more assets owned by a number of parties; and

responsive to detecting a change in the number of parties that own the one or more assets,

generating N child cryptographic keys based on the parent cryptographic key by applying a predetermined algorithm to the parent cryptographic key, wherein N is an integer greater than or equal to 2 corresponding to a current number of parties that own the one or more assets;

wherein applying the predetermined algorithm to the parent cryptographic key comprises generating N−1 random numbers having bit-lengths equal to a bit-length of the parent cryptographic key and performing a series of bitwise XOR operations between the parent cryptographic key and a first random number of the N−1 random numbers to generate a first output then sequentially performing XOR operations between an output of a previous XOR operation and a random number not previously used to generate an XOR child cryptographic key and obtain the N child cryptographic keys, wherein the N child cryptographic keys include the XOR child cryptographic key and the N−1 random numbers;

receiving a plurality of cryptographic keys comprising the XOR child cryptographic key and the N−1 random numbers;

determining a number of the received plurality of cryptographic keys is equal to the number of parties sharing control over the blockchain object; and

in response to determining that the number of the received plurality of cryptographic keys is equal to the number of parties sharing control over the blockchain object, reconstructing the parent cryptographic key by performing a series of bitwise XOR operations, sequentially, on the received plurality of cryptographic keys and referencing third party auxiliary data.

8. The computer-implemented system of claim 7 , wherein the operations further comprise:

transmitting the N child cryptographic keys to corresponding parties; and

deleting the parent cryptographic key.

9. The computer-implemented system of claim 7 , wherein applying the predetermined algorithm to the parent cryptographic key comprises:

modifying the parent cryptographic key based on a randomly generated character string.