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On Thursday 27 October 2005 07:53, James wrote: |
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> Well, there are lot's of ways to 'skin the cat' here. |
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> |
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> Here's a good overview of some of the tools tools that you could use: |
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> http://www.gentoo.org/doc/en/security/ |
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> security-handbook.xml?part=1&chap=12#doc_chap1 |
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> The section on Squid would apply particularly to you. |
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> |
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> <snip> |
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> In this case, my policy states: |
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> * Surfing (HTTP/HTTPS) is allowed during work hours (mon-fri 8-17 and |
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> sat 8-13), but if employees are here late they should work, not surf |
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> * Downloading files is not allowed (.exe, .com, .arj, .zip, .asf, .avi, |
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> .mpg, .mpeg, etc) |
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> * We do not like banners, so they are filtered and replaced with a |
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> transparent gif (this is where you get creative!). |
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> * All other connections to and from the Internet are denied. |
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> <snip> |
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would it be possible to see an example of the squid config that does this? |
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> |
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> You'll most likely need a good firewall and an Aplication Level Gateway |
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> (ALG) to get roboust control of your networks. |
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> |
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> On the firewall side of things, I have taken the 'painful' but superior |
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> route to learning/testing/reading/test/reading_some_more/testing..... |
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> to use raw ipfilter/netfilter to achieve fine grain control of networks. |
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> |
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> Others will recommend you use a 'canned firewall' technology, such as |
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> shorewall, fwbuilder (etc) along with various packages that create |
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> your ALG. |
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> |
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> Learning raw ipfilter/netfilter is a very time consuming process, but, |
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> well worth the effort, in my experience. With the help of this list, |
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> you can achieve robust control over your networks, but, it |
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> does take time. The good thing about investing the time in a linux |
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> setting, is once you have a network management system in place, it's |
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> very straight forward to maintain, you do not have to spend money |
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> or waste time on vendors, and you learn how to *TEST* what you have |
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> to verify it works properly. Using a vendor, makes you subjectively |
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> vulnerable to the vendor's financial goals and technical limitations. |
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> You'll not likely be able to afford a company that has 1/10th the |
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> security expertise, that this list offers for free. |
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> |
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> Regardless of the path you choose, you have to test, modify and test |
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> your network again, with a variety of tools, to ensure robust content |
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> control and sufficient security. |
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> |
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> I'll assume you want the easy, minimal_pain route to controlling your |
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> networks, so I'll let the others pitch easy solutions, that allow |
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> use of software package such as shorewall + squid etc. |
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> |
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> If you want some more links to read about raw ipfilters, just let me know. |
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> |
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> HTH, |
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> James |
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|
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-- |
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John Jolet |
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Your On-Demand IT Department |
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512-762-0729 |
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www.jolet.net |
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john@×××××.net |
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-- |
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