Oblivious TLS via Multi-party Computation

In this paper, we describe Oblivious TLS: an MPC protocol that we prove UC secure against a majority of actively corrupted parties. The protocol securely implements TLS 1.3. Thus, any party P who runs TLS can communicate securely with a set of servers running Oblivious TLS; P does not need to modify anything, or even be aware that MPC is used.

Applications of this include communication between servers who offer MPC services and clients, to allow the clients to easily and securely provide inputs or receive outputs. Also, an organization could use Oblivious TLS to improve in-house security while seamlessly connecting to external parties.

Our protocol runs in the preprocessing model, and we did a preliminary non-optimized implementation of the on-line phase. In this version, the hand-shake completes in about 1 s. Based on implementation results from other work, performance of the record protocol using the standard AES-GCM can be expected to achieve an online throughput of about 3 MB/s.