Key ceremony of a security system forming part of a host computer for cryptographic transactions

• US 9,735,958 B2
• Filed: 05/19/2015
• Issued: 08/15/2017
• Est. Priority Date: 05/19/2015
• Status: Active Grant

• Current Assignee: Coinbase, Inc.
• Original Assignee: Coinbase, Inc.
• Inventors: Alness, Andrew E., Hudon, James Bradley
• Primary Examiner(s): GRACIA, GARY S
• Application Number:
  US14/716,100
• Publication Number:
  US 20160344543A1
• Time in Patent Office: 819 Days
• Field of Search: 713170, 713171, 713175, 713168, 380227, 380282
• CPC Class Codes: G06Q 20/065 using e-cash
• CPC Class Codes: G06Q 20/3823 combining multiple encryption tools for a transaction
• CPC Class Codes: H04L 63/00 Network architectures or network communication protocols for network security cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00; network architectures or network communication protocols for wireless network security H04W12/00; security arrangements for protecting computers or computer systems against unauthorised activity G06F21/00
• CPC Class Codes: H04L 63/06 for supporting key management in a packet data network cryptographic mechanisms or cryptographic arrangements for key management H04L9/08
• CPC Class Codes: H04L 63/166 at the transport layer
• CPC Class Codes: H04L 9/0819 Key transport or distribution, i.e. key establishment techniques where one party creates or otherwise obtains a secret value, and securely transfers it to the other(s) network architectures or network communication protocols for key distribution in a packet data network H04L63/062
• CPC Class Codes: H04L 9/0822 using key encryption key
• CPC Class Codes: H04L 9/085 Secret sharing or secret splitting, e.g. threshold schemes
• CPC Class Codes: H04L 9/0863 involving passwords or one-time passwords network architectures or network communication protocols for using one-time keys in a packet data network H04L63/067

Abstract

A key ceremony application creates bundles for custodians encrypted with their passphrases. Each bundle includes master key share. The master key shares are combined to store an operational master key. The operational master key is used for private key encryption during a checkout process. The operational private key is used for private key decryption for transaction signing in a payment process. The bundles further include TLS keys for authenticated requests to create an API key for a web application to communicate with a service and to unfreeze the system after it has been frozen by an administrator.

Claims

1. A host computer system comprising:

a key ceremony application associated with a computing device comprising a memory

creates a for-distribution master key,

store the for-distribution master key in the memory connected to the key ceremony application,

split the for-distribution master key into N shares,

create a plurality of custodian transport layer security (TLS) keys that are different from one another,

create a certificate authority that creates a service TLS key,

create N bundles, each bundle including a respective one of the N shares, a respective one of the different custodian TLS keys and the service TLS key;

distribute the respective shares among N custodians, each custodian being associated with a respective computing device, and

clear the for-distribution master key, custodian TLS keys and the service TLS key from the memory of the computing device associated with the key ceremony application;

a service associated with a different computing device comprising a different memory separate from the key ceremony application performs operations to;

communicate over a communication network with respective computing devices of M of the N custodians to receive at least M of the N shares, where M is equal to or less than N,

derive an operational master key from the M shares, and

store the operational master key in memory connected to the service; and

a web application associated with a computing device

communicates over the communication network with a customer computer system to execute a checkout process only after the operational master key is stored in the memory connected to the service over the communication network.

2. The host computer system of claim 1, wherein the key ceremony application is configured to receive a passphrase from each custodian, and encrypt each bundle with a respective passphrase of a respective custodian.

3. A method of distributing security data to custodians comprising:

creating, by a key ceremony application associated with a computing device comprising a memory, a for-distribution master key;

storing, by the key ceremony application, the for-distribution master key in memory connected to the key ceremony application;

splitting, by the key ceremony application, the for-distribution master key into N shares;

creating, by the key ceremony application, a plurality of custodian transport layer security (TLS) keys that are different from one another;

creating, by the key ceremony application, a certificate authority that creates a service TLS key;

creating, by the key ceremony application, N bundles, each bundle including a respective one of the N shares, a respective one of the different custodian TLS keys and the service TLS key;

distributing, by the key ceremony application, the respective shares among N custodians, each custodian being associated with a respective computing device;

clearing, by the key ceremony application, the for-distribution master key, custodian TLS keys and the service TLS key from the memory of the computing device associated with the key ceremony application;

communicating, by a master key loader of a service associated with a different computing device comprising a different memory separate from the key ceremony application, over a communication network with respective computing devices of M of N custodians to receive at least M of the N shares, where M is equal to or less than N; and

deriving, by the master key loader, the operational master key from the M shares before storing the operational master key in the memory

storing, by the master key loader, the operational master key in memory connected to the service; and

communicating, using a web application configured associated with a computing device, over the communication network with a customer computer system, to execute a checkout process only after the operational master key is stored in the memory connected to the service over the communication network.

4. The method of claim 3, further comprising:

receiving a passphrase from each custodian; and

encrypting each bundle with a respective passphrase of a respective custodian.

5. A non-transitory computer-readable medium having stored thereon a set of instructions that, when executed by a processor of a computer carries out a method of distributing security data to custodians comprising:

creating, by a key ceremony application associated with a computing device comprising a memory, a for-distribution master key;

storing, by the key ceremony application, the for-distribution master key in memory connected to the key ceremony application;

splitting, by the key ceremony application, the for-distribution master key into N shares;

creating, by the key ceremony application, a plurality of custodian transport layer security (TLS) keys that are different from one another;

creating, by the key ceremony application, a certificate authority that creates a service TLS key;

creating, by the key ceremony application, N bundles, each bundle including a respective one of the N shares, a respective one of the different custodian TLS keys and the service TLS key;

distributing, by the key ceremony application, the respective shares among N custodians, each custodian being associated with a respective computing device;

clearing, by the key ceremony application, the for-distribution master key, custodian TLS keys and the service TLS key from the memory of the computing device associated with the key ceremony application;

communicating, by a master key loader of a service associated with a different computing device comprising a different memory separate from the key ceremony application, over a communication network with respective computing devices of M of N custodians to receive at least M of the N shares, where M is equal to or less than N; and

deriving, by the master key loader, the operational master key from the M shares before storing the operational master key in the memory

storing, by the master key loader, the operational master key in memory connected to the service; and

communicating, using a web application associated with a computing device, over the communication network with a customer computer system, to execute a checkout process only after the operational master key is stored in the memory connected to the service over the communication network.