[squid-users] Using a Baltimore root certificate in transparent ssl proxying

Antony Stone Antony.Stone at squid.open.source.it
Tue Apr 28 08:42:27 UTC 2020

On Monday 27 April 2020 at 23:44:41, Lei Wen wrote:

> The issue we are having right now is the certificate installed on the
> container is a self signed cert, we were trying to migrate this cert to a
> real trusted CA cert, or a Baltimore root cert.

That will not work for an intercepting ("transparent") proxy.

> I do notice that it is illegal for a trusted CA to issue official cert to
> squid because squid itself is man-in-the-middle, so Squid can only accept
> self signed cert and squid as root CA?

This is correct.

Squid is acting as a man-in-the-middle for *any* web request your users choose 
to pass through it, therefore it has to present a certificate to their browser 
which is valid for whatever domain they have requested.

In effect, it would need a wildcard certificate for the entire Internet.

No CA is going to give you that.



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