Key updating method and apparatus, file sharing method and apparatus, device, and computer storage medium

1. A key updating method, comprising:

acquiring a target root key and an auxiliary target root key;

acquiring identity information of a data owner of target data;

acquiring a target timestamp when the target data is encrypted;

acquiring a key generation parameter and an auxiliary key that are generated at a timestamp previous to the target timestamp; and

generating a target private key of the data owner based on the key generation parameter at the timestamp previous to the target timestamp, the auxiliary key at the timestamp previous to the target timestamp, the identity information and the target timestamp, wherein the key generation parameter generated at a timestamp previous to a starting timestamp is the target root key; and the auxiliary key generated at the timestamp previous to the starting timestamp is the auxiliary target root key;

wherein the generating a target private key of the data owner based on the key generation parameter at the timestamp previous to the target timestamp, the auxiliary key at the timestamp previous to the target timestamp, the identity information and the target timestamp comprises:

generating key metadata at the target timestamp by performing a Hash operation on the key generation parameter generated at the timestamp previous to the target timestamp and the auxiliary key generated at the timestamp previous to the target timestamp;

generating the auxiliary key at the target timestamp by performing a Hash operation on the auxiliary key generated at the timestamp previous to the target timestamp and the target timestamp; and

generating the target private key of the data owner based on a first half of the key metadata at the target timestamp, the auxiliary key at the target timestamp, the identity information and the target timestamp,

wherein the key generation parameter generated at the timestamp previous to the target timestamp is a second half of the key metadata generated at the timestamp previous to the target timestamp.

2. The method according to claim 1 , wherein the generating the target private key of the data owner based on a first half of the key metadata at the target timestamp, the auxiliary key at the target timestamp, the identity information and the target timestamp comprises:

calculating a Hash value of the identity information and the target timestamp;

calculating a product value of the auxiliary key at the target timestamp and the Hash value; and

using a sum of the first half of the key metadata at the target timestamp and the product value as the target private key of the data owner.

3. The method according to claim 2 , wherein types of the target private key comprise a target symmetric key, and a target asymmetric private key, wherein

in response to the target private key being the target symmetric key, the target root key is a target symmetric root key, and the auxiliary target root key is an auxiliary symmetric root key; and in response to the target private key being the target asymmetric private key, the target root key is a target asymmetric root key, and the auxiliary target root key is an auxiliary asymmetric root key.

4. The method according to claim 3 , wherein after the generating a target private key of the data owner based on the key generation parameter at the timestamp previous to the target timestamp, the auxiliary key at the timestamp previous to the target timestamp, the identity information and the target timestamp, the method further comprises:

in response to the target private key being the target asymmetric private key, generating a target asymmetric public key based on the target asymmetric private key.

5. An electronic device, comprising:

a memory, configured to store a computer program therein; and

a processor, configured to execute the computer program to implement operations of:

acquiring a target root key and an auxiliary target root key;

acquiring identity information of a data owner of target data;

acquiring a target timestamp when the target data is encrypted;

acquiring a key generation parameter and an auxiliary key that are generated at a timestamp previous to the target timestamp; and

generating a target private key of the data owner based on the key generation parameter at the timestamp previous to the target timestamp, the auxiliary key at the timestamp previous to the target timestamp, the identity information and the target timestamp,

wherein the key generation parameter generated at a timestamp previous to a starting timestamp is the target root key; and the auxiliary key generated at the timestamp previous to the starting timestamp is the auxiliary target root key;

wherein the generating a target private key of the data owner based on the key generation parameter at the timestamp previous to the target timestamp, the auxiliary key at the timestamp previous to the target timestamp, the identity information and the target timestamp comprises:

generating key metadata at the target timestamp by performing a Hash operation on the key generation parameter generated at the timestamp previous to the target timestamp and the auxiliary key generated at the timestamp previous to the target timestamp;

generating the auxiliary key at the target timestamp by performing a Hash operation on the auxiliary key generated at the timestamp previous to the target timestamp and the target timestamp; and

generating the target private key of the data owner based on a first half of the key metadata at the target timestamp, the auxiliary key at the target timestamp, the identity information and the target timestamp,

wherein the key generation parameter generated at the timestamp previous to the target timestamp is a second half of the key metadata generated at the timestamp previous to the target timestamp.

6. A non-transient computer-readable storage medium storing a computer program that, when being executed by a processor, implements steps of the method according to claim 1 .

7. The electronic device according to claim 5 , wherein the processor is further configured to perform operations of:

calculating a Hash value of the identity information and the target timestamp;

calculating a product value of the auxiliary key at the target timestamp and the Hash value; and

using a sum of the first half of the key metadata at the target timestamp and the product value as the target private key of the data owner.

8. The electronic device according to claim 7 , wherein types of the target private key comprise a target symmetric key, and a target asymmetric private key, wherein

in response to the target private key being the target symmetric key, the target root key is a target symmetric root key, and the auxiliary target root key is an auxiliary symmetric root key; and in response to the target private key being the target asymmetric private key, the target root key is a target asymmetric root key, and the auxiliary target root key is an auxiliary asymmetric root key.

9. The electronic device according to claim 8 , wherein the processor is further configured to perform operations of:

in response to the target private key being the target asymmetric private key, generating a target asymmetric public key based on the target asymmetric private key.

10. The electronic device according to claim 5 , wherein the identity information is the data user's ID or ID number.

11. The method according to claim 1 , wherein the identity information is the data user's ID or ID number.