Cryptoasset custodial system with vault-specific rules governing different actions allowed for different vaults

1. A method comprising:

receiving a request to take an action with respect to a vault in a cryptoasset custodial system, wherein the action comprises a change to a policy map associated with the vault, wherein the associated policy map defines vault control rules governing which actions are allowed for the vault;

authenticating, by a hardware security module managing private keys of cryptographic key pairs usable to control access to cryptoassets associated with a customer account of the cryptoasset custodial system, the policy map for the vault on which the action is requested based on a cryptographic key controlled by the hardware security module;

checking, by the hardware security module, the action against the policy map for the vault when the policy map for the vault is authenticated based on the cryptographic key controlled by the hardware security module; and

effecting, by the hardware security module, the action when the action is confirmed to be in accordance with the policy map for the vault by:

generating an updated version of the policy map including the requested change;

digitally signing the updated version of the policy map using the cryptographic key controlled by the hardware security module; and

storing resulting digital signature data for future use by the hardware security module,

wherein the action comprising the change to the policy map includes at least one of: adding a new user to the customer account, removing an existing user from the customer account, updating a user access level of one or more existing users of the customer account, or modifying a threshold number of users of the cryptoasset custodial system required to approve the action.

2. The method of claim 1 , wherein the hardware security module comprises at least one secure storage device and at least one physical computing device coupled to the at least one secure storage device, the at least one physical computing device being configured to provide cryptographic processing to manage, for the customer account, the private keys of the cryptographic key pairs.

3. The method of claim 1 , wherein the vault control rules of the policy map for the vault specify, for the action, a plurality of users of the cryptoasset custodial system and the threshold number of the plurality of users required to approve the action.

4. The method of claim 3 , wherein checking the action against the policy map for the vault comprises:

validating a plurality of endorsement messages from at least a subset of the specified plurality of users, and

confirming that the action is in accordance with the vault control rules of the policy map when the plurality of endorsement messages have been validated for the threshold number of the specified plurality of users.

5. The method of claim 4 , wherein validating the plurality of endorsement messages comprises checking cryptographic digital signatures using public keys corresponding to the subset of the specified plurality of users.

6. The method of claim 1 , wherein effecting the action further comprises transmitting the resulting digital signature data to at least one blockchain.

7. A system comprising:

a hardware security module configured to execute instructions to perform operations comprising:

receiving a request to take an action with respect to a vault in a cryptoasset custodial system, wherein the action comprises a change to a policy map associated with the vault, wherein the associated policy map defines vault control rules governing which actions are allowed for the vault;

authenticating the policy map for the vault on which the action is requested based on a cryptographic key controlled by the hardware security module, the hardware security module managing private keys of cryptographic key pairs usable to control access to cryptoassets associated with a customer account of the cryptoasset custodial system;

checking the action against the policy map for the vault when the policy map for the vault is authenticated based on the cryptographic key controlled by the hardware security module; and

effecting the action when the action is confirmed to be in accordance with the policy map for the vault by:

generating an updated version of the policy map including the requested change;

digitally signing the updated version of the policy map using the cryptographic key controlled by the hardware security module; and

storing resulting digital signature data for future use by the hardware security module,

wherein the action comprising the change to the policy map includes at least one of: adding a new user to the customer account, removing an existing user from the customer account, updating a user access level of one or more existing users of the customer account, or modifying a threshold number of users of the cryptoasset custodial system required to approve the action.

8. The system of claim 7 , wherein the hardware security module comprises at least one secure storage device and at least one physical computing device coupled to the at least one secure storage device, the at least one physical computing device being configured to provide cryptographic processing to manage, for the customer account, the private keys of the cryptographic key pairs.

9. The system of claim 7 , wherein the vault control rules of the policy map for the vault specify, for the action, a plurality of users of the cryptoasset custodial system and the threshold number of the plurality of users required to approve the action.

10. The system of claim 9 , wherein checking the action against the policy map for the vault comprises:

validating a plurality of endorsement messages from at least a subset of the specified plurality of users, and

confirming that the action is in accordance with the vault control rules of the policy map when the plurality of endorsement messages have been validated for the threshold number of the specified plurality of users.

11. The system of claim 10 , wherein validating the plurality of endorsement messages comprises checking cryptographic digital signatures using public keys corresponding to the subset of the specified plurality of users.

12. The system of claim 7 , wherein effecting the action further comprises transmitting the resulting digital signature data to at least one blockchain.

13. A non-transitory computer-readable medium storing computer-executable instructions, which, when executed by a hardware security module, cause the hardware security module to perform operations comprising:

receiving a request to take an action with respect to a vault in a cryptoasset custodial system, wherein the action comprises a change to a policy map associated with the vault, wherein the associated policy map defines vault control rules governing which actions are allowed for the vault;

authenticating the policy map for the vault on which the action is requested based on a cryptographic key controlled by the hardware security module, the hardware security module managing private keys of cryptographic key pairs usable to control access to cryptoassets associated with a customer account of the cryptoasset custodial system;

checking the action against the policy map for the vault when the policy map for the vault is authenticated based on the cryptographic key controlled by the hardware security module; and

effecting the action when the action is confirmed to be in accordance with the policy map for the vault by:

generating an updated version of the policy map including the requested change;

digitally signing the updated version of the policy map using the cryptographic key controlled by the hardware security module; and

storing resulting digital signature data for future use by the hardware security module,

wherein the action comprising the change to the policy map includes at least one of: adding a new user to the customer account, removing an existing user from the customer account, updating a user access level of one or more existing users of the customer account, or modifying a threshold number of users of the cryptoasset custodial system required to approve the action.

14. The computer-readable medium of claim 13 , wherein the hardware security module comprises at least one secure storage device and at least one physical computing device coupled to the at least one secure storage device, the at least one physical computing device being configured to provide cryptographic processing to manage, for the customer account, the private keys of the cryptographic key pairs.

15. The computer-readable medium of claim 14 , wherein the vault control rules of the policy map for the vault specify, for the action, a plurality of users of the cryptoasset custodial system and the threshold number of the plurality of users required to approve the action.

16. The computer-readable medium of claim 15 , wherein checking the action against the policy map for the vault comprises:

validating a plurality of endorsement messages from at least a subset of the specified plurality of users, and

confirming that the action is in accordance with the vault control rules of the policy map when the plurality of endorsement messages have been validated for the threshold number of the specified plurality of users.

17. The computer-readable medium of claim 16 , wherein validating the plurality of endorsement messages comprises checking cryptographic digital signatures using public keys corresponding to the subset of the specified plurality of users.