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winkelman

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I would like to block certain secure HTTPS websites, based on their URL. It says in the manual:

Quote:

Connections must not be encrypted. SSL encrypted traffic (HTTPS and FTPS protocols) cannot be monitored. In this case you can block access to certain servers using traffic rules (see chapter Definition of Custom Traffic Rules).

Note: If the proxy server is used (see chapter Proxy server), It is also possible to filter HTTPS servers (e.g. https://www.kerio.com/). However, it is not possible to filter individual objects at these servers.

(I would rather not use the proxy server, to keep things as simple (and my life as headache free) as possible.)

So now I'm trying to block the sites through Traffic Rules (as suggested in the manual), however, I am unable to get this to work. I want to block the website https://webmail.xs4all.nl/src/login.php so I made a Traffic Rule as follows and placed it ABOVE the rule that allows normal HTTP(S) traffic:

Source: <internal interface> (will later be specific group of users)
Destination: host webmail.xs4all.nl
Service: HTTPS
Action: Deny
Log:
Translation: NAT (default outgoing interface)
Protocol Inspector: Default

This does not work, I can still access the site. Can anybody help? Much appreciated...

More and more of the Internet is getting secure (lot's of webmail sites I want to block for example) and so KWF is losing more and more of it's potential to regulate Internet usage if I am not able do block specific HTTPS sites in an easy way.

I understand KWF cannot look 'into' a HTTPS connection, nonetheless it should be possible to block HTTPS connections to certain URL's. Preferrably in the 'Content Filtering - HTTP Policy' context. Then there would be ONE place for blocking certain websites. The initial DNS requests etc. are not encrypted. So KWF may see someone trying to setup a HTTPS connection to a website which is forbidden and block it. Yes? No? Consider this a feature request...

[Updated on: Fri, 27 May 2005 14:50]

  •  
feite

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Check if the traffic rule is above the traffic rule that allows access to https sites. Rules are checked from top to bottom until a match is found.

You can change the behaviour by blocking all HTTPS unless its allowed:

name: HTTPS (from LAN only)
source: LAN
dest: address group of allowed HTTPS urls
service: HTTPS
action: allow
translation: nat default outgoing interface

name: block HTTPS (for LAN and firewall)
source: LAN, firewall
dest: internet
service: HTTPS
action: deny

This should work fine. Sites that are allowed are added to the address group.
  •  
winkelman

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The traffic rule is above the rule that allows HTTP(S) traffic.

I do not want to restrict access to all HTTPS servers, except some... I want to allow access to HTTPS sites, except some...

(This above is some months ago, I will try it now again with KWF 6.1.1, maybe something changed...)

[Updated on: Mon, 25 July 2005 12:08]

  •  
winkelman

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Follow up:

Well, blocking of HTTPS sites works now Cool. Probably it was just me doing something wrong of course (or mabybe something has changed in recent versions of KWF).

Anyway, I made a rule to block HTTPS traffic to addresses in the address group 'blocked HTTPS sites'. This rule is placed above the rule which allows HTTP(S) traffic in general. When I want to block a certain HTTPS-site, I just add the domain to the address group 'blocked HTTPS sites'.

(There is still the HTTPS issue that people can visit HTTPS sites without being authenticated, even though my setup requires authentication.)
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