From 94f4274e8f863ebe2e3e5b96b8d5cff4828a4ead Mon Sep 17 00:00:00 2001 From: Nico Schottelius Date: Thu, 7 Nov 2019 19:04:52 +0100 Subject: [PATCH] +ports --- .../contents.lr | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/content/u/blog/nftables-magic-redirect-all-ports-to-one-port/contents.lr b/content/u/blog/nftables-magic-redirect-all-ports-to-one-port/contents.lr index 96c131c..9c2f7d0 100644 --- a/content/u/blog/nftables-magic-redirect-all-ports-to-one-port/contents.lr +++ b/content/u/blog/nftables-magic-redirect-all-ports-to-one-port/contents.lr @@ -92,6 +92,22 @@ restrict the ports to be used for ssh. You can either use **sets** tcp dport {23, 25, 80, 443 } redirect to :ssh ``` +(just replace the *tcp dport != ...* line above)! + +## "Good ports" + +Over time you will see that there are some ports which are more likely +to be open, even if the network filters your traffic. Some well known +ports for this are: + +* 80: regular http traffic +* 53: DNS, uses UDP by default, but TCP is also part of the standard +* 443: usually has encrypted https traffic +* 783: smtp submission port for sending out emails + +Of course, if the filtering uses deep packet inspection, this will +fail, but then there are other solutions for that... stay tuned!! + ## More of it? If you are interested in more of this, we invite you to join our