Re: Shorewall 5.2.3.2 Events - Port Knocking

Jean-Francois Bogaerts <[email protected]>
Newsgroups gmane.comp.security.shorewall
Message-ID <[email protected]>
Hi,

If I comment out

#REJECT  net     fw      tcp     8123


This port is permanently open whatever I knock 1600 or 1599


JF Bogaerts
------------------------------------------------------------------------
On 5/12/21 18:22, Justin Pryzby wrote:
> On Sun, Dec 05, 2021 at 05:50:44PM +0100, Jean-Francois Bogaerts wrote:
>> Using command "shorewall show events" I can see the event was triggered but
>> the relevant port action is not taked into account
>>
>>  From the log I can see ACCEPT and REJECT actions
>> Dec  5 17:22:46 nltsystem1 kernel: [436257.294886] SSHKnock ACCEPT IN=eth1 OUT= MAC=00:1e:10:1f:00:00:00:10:20:30:40:50:08:00 SRC=95.182.129.33 DST=192.168.8.100 LEN=60 TOS=0x00 PREC=0x00 TTL=48 ID=8083 DF PROTO=TCP SPT=48364 DPT=1600 WINDOW=64240 RES=0x00 SYN URGP=0
>> Dec  5 17:22:57 nltsystem1 kernel: [436268.464919] SSHKnock REJECT IN=eth1 OUT= MAC=00:1e:10:1f:00:00:00:10:20:30:40:50:08:00 SRC=95.182.129.33 DST=192.168.8.100 LEN=60 TOS=0x00 PREC=0x00 TTL=48 ID=7950 DF PROTO=TCP SPT=39338 DPT=1599 WINDOW=64240 RES=0x00 SYN URGP=0
>> I'm using the bare sample except that I want to open or close TCP port 8123
>> REJECT  net     fw      tcp     8123
>> SSHKnock:info   net               fw            tcp 8123,1599-1601
> The first rule is hit first, so you're always rejecting 8123, rather than
> conditionally allowing it.
>
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.