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0 pointsnpteljes1y ago0 comments

This is very nitpicky, and not even valid at that.

First, I think authorization is even more valid than authentication. In this context, it's the authority is what is important, so that only the designated entities can assert control over the system, and not others.

Second, it's very hard to imagine authorization on an open channel like radio, without any sort of encryption. In fact, only the one-time pad comes to mind, although I'm far from being a proper security person. What I see is that authority is usually demonstrated through some encrypted means - even if the message itself is unencrypted, its digital signature is.

>another non authentic but encrypted HTTPS is one such channel. The weakest guarantee of HTTPS is that the comms between the client and the HTTPS terminating server is encrypted, nothing more. HTTPS security can be upgraded to include authenticity information, but it's not mandatory, and it's still very useful even in this weaker form.

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H8crilA1y ago

Authentic channel is a channel typically uses digital signatures, or MACs, or something like the Dragonfly protocol used for example in WPA3. As you may know the padlock and alerts in browsers are exactly for that reason, to show that a channel is authentic. The client doesn't authenticate by default, we use passwords/API keys/oauth/etc for that. Though the client actually can, and some services use that.

> Second, it's very hard to imagine authorization on an open channel like radio, without any sort of encryption.

It's easy: you add digital signatures to sign plaintext packets/messages. And now you know they are authentic, and not generated by some random guy that bought a HackRF last week, and is now testing all firmwares that he can find.

nextaccountic1y ago

I think the point made is that digital signatures are encrypted messages (eg. you may encrypt a hash of the message using your private key)

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Scaevolus1y ago

Authorization can be achieved by authentication with either a preshared key or a key derived using public key cryptography and some PKI.

It's trivial to implement on an open channel, HMAC being a common form. This is how old APIs using HTTP (Flickr, S3) handled authorization despite all communication being cleartext.

Confidentiality and integrity can be achieved with a single authenticated encryption primitive, or done separately with encryption and a hash-based authentication primitive, or exist as one without the other.

radicality1y ago

Didn’t the parent talk about authentication vs encryption, and not authentication vs authorization ?

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