----- Original Message ----- From: "Denis Vlasenko" <vda@xxxxxxxxxxxxx> To: "fooler" <fooler@xxxxxxxxxxx>; <squid-users@xxxxxxxxxxxxxxx>; "Niels" <zorglub_olsen@xxxxxxxxxxx> Sent: Friday, May 13, 2005 4:57 PM Subject: Re: [squid-users] Re: RE: How do I hide port 3128? > > the simple logic and attack of nmap is that, it send a *tcp syn* to the > > target host... if the the target host reply a *tcp syn/ack*... then nmap > > will display that port is *open* otherwise nmap will assumed that port is > > *filtered*... therefore, filtering thru packet filter, binding to > > localhost, whatever trick you gonna do... it will give you the same results > > from nmap... > > Not entirely correct info. > > Filtering with -DROP will make host NOT answer SYNs to 3128 at all, > thus nmap will show this port as 'filtered'. your explanation is the same as mine... so what is incorrect in there? > Binding squid to 127.0.0.1:3128 will make host reply with RSTs > ("I don't have this port open, go away"), nmap will show 'closed'. yes it will display *closed* when the target host reply with a RST packet... but my statement above is only about when a target host replies either tcp syn/ack or not at all.... fooler.