iptables: How to read this OPT string?
- by alex
I have a simple INPUT rule for iptables that logs any new connections to a logfile.
--log-tcp-options and --log-ip-options flags are both set and I get the appropriate OPT output.
One line of my log looks something like this:
Nov 29 17:00:00 IN=venet0 OUT= MAC= SRC=x.x.x.x DST=x.x.x.x LEN=64
TOS=0x00 PREC=0x00 TTL=53 ID=37898 DF PROTO=TCP SPT=57755 DPT=8888
WINDOW=65535 RES=0x00 SYN URGP=0 OPT
(0204057D010303010101080A3E521D4D0000000004020000)
I would like to understand how to interpret the OPT string (bold).
Is there some documentation available on what it actually means?
How could I make it human-readable?