Selfhosted

38707 readers

677 users here now

A place to share alternatives to popular online services that can be self-hosted without giving up privacy or locking you into a service you don't control.

Rules:

Be civil: we're here to support and learn from one another. Insults won't be tolerated. Flame wars are frowned upon.
No spam posting.
Posts have to be centered around self-hosting. There are other communities for discussing hardware or home computing. If it's not obvious why your post topic revolves around selfhosting, please include details to make it clear.
Don't duplicate the full text of your blog or github here. Just post the link for folks to click.
Submission headline should match the article title (don’t cherry-pick information from the title to fit your agenda).
No trolling.

Resources:

Any issues on the community? Report it using the report flag.

Questions? DM the mods!

founded 1 year ago

MODERATORS

[email protected]

Could someone explain the networking behind transparent proxies and MiTM snooping using certificates to me? (lemmy.world)

submitted 11 months ago by [email protected] to c/[email protected]

27 comments fedilink hide all child comments

Hi everyone, I've been trying to understand how MiTM setups like a transparent proxy work.

Obviously, the use-case here is in a personal scope: I'd like to inspect the traffic of some of my machines. I am aware that Squid can be a transparent proxy, and some might use the Burp Suite to analyse network traffic.

Could someone explain the basic networking and the concept of certificates in this scenario? I feel like I don't understand how certificates are used well enough.

For example: I realise that if someone inserts a root certificate in the certificate store of an OS, the machine trusts said CA, thus allowing encrypted traffic from the machine to be decrypted. However, say the machine was trying to access Amazon; won't Amazon have its own certificate? I don't know how I'm confused about such a simple matter. Would really appreciate your help!

you are viewing a single comment's thread
view the rest of the comments

[–] [email protected] 1 points 11 months ago (1 children)

Ah, I see. I suppose I got a bit confused, and wanted to confirm how encryption would work for outbound traffic. Just to be sure: when an application wants to send encrypted data to a website/service on the Internet, it will use the respective certificate for said website. However, if one runs a transparent proxy in the middle and inserts a root certificate in the certificate store of the application, said certificate becomes valid (and the de-facto pick) for all websites, and this is what the client begins to use for everything.

Is that how it works?

[–] [email protected] 1 points 11 months ago (1 children)

Not quite. This might be a better explanation than I'm providing: https://chat.openai.com/share/c77fc7ed-9d68-4076-ab70-e953a3896bb6

[–] [email protected] 1 points 11 months ago

Indeed, that is what I meant to say. Thanks for the link. I'm assuming that transparent proxies have some sort of certificate store in them, since they connect as the user to different websites?