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dalek-cryptography / x25519-dalek

X25519 elliptic curve Diffie-Hellman key exchange in pure-Rust, using curve25519-dalek.
BSD 3-Clause "New" or "Revised" License
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Make `SharedSecret` (de)serializable #94

Closed pierre-l closed 1 year ago

pierre-l commented 1 year ago

Hello!

All is in the title: I'd like for SharedSecret to be (de)serializable. Is this fine?

tarcieri commented 1 year ago

It sure seems odd to me for SharedSecret to be serializable. Its purpose is to be established without ever being transmitted over the wire.

I’m not sure what use cases you have in mind, but in pretty much any of them I would think it makes more sense to derive some other value from the SharedSecret first before transmitting it over the wire, which allows it to be bound to a particular application. That’s how e.g. TLS 1.3 session resumption works, for example.

pierre-l commented 1 year ago

To be frank I'm not 100% sure I will need this, but even if I do it will not exactly be transmitted over the wire. I'll get back to you once I get a more expert opinion on the exact use case.

pierre-l commented 1 year ago

I'm closing this until I get more details on the exact use case.