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Etaoin Shrdlu wrote: |
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> On Tuesday 24 February 2009, 18:21, Florian Philipp wrote: |
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>> Nikos Chantziaras schrieb: |
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>>> Grant wrote: |
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>>>> How can I find out whether I should be specifying TCP, UDP, or both |
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>>>> for iptables (shorewall) config? |
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>>> By knowing the application's protocol for which you write the rules |
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>>> for :P [...] So you have to research a bit to see if the |
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>>> application uses TCP or UDP. |
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>> You can also have a look at /etc/services which lists the more |
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>> common protocols and their ports. |
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> |
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> Or even sniff the traffic and see which protocols are used. |
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> |
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You're going to miss stuff that way. Take for example a DNS server. |
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Normally requests are UDP over port 53. However once your request |
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exceeds 512 bytes TCP is used on port 53. That rarely happens and in |
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fact many ISPs don't seem to be aware that this can happen. |
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Chances are you're going to find almost everything you need at |
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http://www.shorewall.net/Documentation_Index.html which is going to far |
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better than trying to cobble everything together yourself. |
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kashani |
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