Re: [Ethereal-users] display filters, how do I say OR? and how do I see only the initial connections?

Guy Harris <guy-FrUbXkNCsVf2fBVCVOL8/[email protected]> Thu, 10 Aug 2006 12:30:53 -0700
Newsgroups gmane.network.wireshark.user,gmane.network.ethereal.user
Message-ID <[email protected]>
james hanley wrote:
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> 
> 1)
> how do I say OR ?
> AND is &&
>  
> for example, I want to say 
> tcp.dstport != 3389 "OR" tcp.srcport != 3389

The same way you do in Wireshark, as per the above, so I'm redirecting 
this to the wireshark-users list.

In Wireshark, just as AND is &&, OR is...

...||.

> 2)
> how do I see only the initial connections? and just incoming or just 
> outgoing?
>  
> is there an  easier way than this? (i'm not even sure if this is right)
>  
> my ip is 192.168.0.2
>  
> for incoming-
> tcp.flags.syn == 1 && tcp.flags.ack==0 && ip.src != 192.168.0.2

That's the correct filter to see attempts by other machines to connect 
to your machine - it matches packets that have SYN set and ACK not set 
(so it's the initial SYN) that are not coming from your machine.

> for outgoing-
> tcp.flags.syn == 1 && tcp.flags.ack==0 && ip.src == 192.168.0.2

Ditto.

No, there's no simpler expression (unless somebody's added a new field 
to the TCP dissector while I wasn't watching).