Data system with information provenance
A secure, integrated data system and method users both blockchain and Trusted Execution Environment (TEE) technologies to achieve information provenance for data, particularly, mobile health device data. Using a blockchain to record and enforce data access policies removes the need to trust a single entity with gatekeeping the health data. Instead, participants form a consortium and collectively partake in verifying and enforcing access policies for data stored in private data silos. Data access and computation takes place inside of TEEs, which preserves data confidentiality and provides a verifiable attestation that can be stored on the blockchain for the purpose of information provenance.
1. A system for maintaining information provenance of confidential data, comprising:
a device generating raw data;
a blockchain network storing smart contracts and provenance metadata; and
a trusted execution environment (TEE) network comprising hardware and software for providing secure execution of instructions stored in a computer-readable memory, said TEE network:
storing the raw data by:
receiving the raw data from the device;
encrypting the raw data to produce a new encrypted data;
storing the new encrypted data in a datastore; and
recording a first provenance metadata on the blockchain network, wherein the first provenance metadata comprises (1) a first hash of the raw data, (2) a first address of the new encrypted data in the datastore, (3) a first key encrypted form of a first encryption key that was used to encrypt the raw data, and (4) a first attestation report generated by a first TEE that stored the new encrypted data; and
performing computations on the new encrypted data in the datastore by:
verifying the first provenance metadata of the new encrypted data retrieved from the datastore in response to a computation request, executing confidential computations on the new encrypted data retrieved from the datastore and storing a result encrypted data in the datastore, wherein the result encrypted data comprises a confidential computation result, a second attestation report, and a list of input set data indexes; and
recording a second provenance metadata on the blockchain network, wherein the second provenance metadata comprises (1) a hash of the result encrypted data, (2) an address of the result encrypted data in the datastore, (3) a second key encrypted form of a second key that was used to encrypt the result encrypted data, and (4) a third attestation report generated by the TEE that stored the result encrypted data, for verifying a result of the confidential computations.
2. The system of claim 1 , further comprising a gateway device receiving the raw data from the device, adding a signature, and sending the raw data and the signature to the TEE network.
3. The system of claim 2 , wherein the gateway device further uploads the raw data into batches to send to the TEE network.
4. The system of claim 1 , wherein the blockchain network comprises a plurality of nodes maintained by a consortium.
5. The system of claim 1 , wherein verifying the first provenance metadata of the new encrypted data retrieved from the datastore further comprises:
receiving a request from an application to access the new encrypted data to perform a computation;
requesting the first provenance metadata from a blockchain interface;
checking whether the application has permission to access the new encrypted data and perform the computation;
when an application has the permission, the blockchain network provides the first provenance metadata, an encrypted computation program, and encrypted data keys;
verifying a signature of the application;
retrieving the new encrypted data from the datastore; and
decrypting the first encrypted key with a master data key, then decrypting the new encrypted data and the encrypted computation program using the decrypted first encrypting key and verifying hashes of the decrypted data.
6. The system of claim 1 , wherein the device for generating raw data is a mobile health device that monitors an aspect of a wearer's health during regular activities.
7. The system of claim 6 , wherein the mobile health device is a smart watch, heart rate monitor or glucose monitor.
8. The system of claim 2 , wherein the gateway device is a smart phone, smartwatch, tablet, laptop, or non-mobile device.
9. The system of claim 8 , wherein the signature added to the raw data by the gateway device identifies a wearer of the device.
10. The system of claim 1 , wherein TEE network is a secure computing environment resistant to privileged software attacks and hardware attacks.