This is not too different from wpa_supplicant used by several operating for key management for wireless networks. The complicated key negotiation and authentication can remain in user space, the encryption of the negotiated key can be done in the kernel (kTLS) or, when eBPF can control both sides, it can even be done without using TLS but encrypting using a network level encapsulation format to it works for non-TCP as well.
This is not too different from wpa_supplicant used by several operating for key management for wireless networks. The complicated key negotiation and authentication can remain in user space, the encryption of the negotiated key can be done in the kernel (kTLS) or, when eBPF can control both sides, it can even be done without using TLS but encrypting using a network level encapsulation format to it works for non-TCP as well.
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