Jörg Harmuth wrote:
Can anyone offer some pointers here? I imagine more of my narc.conf
and/or iptables' output would be helpful, but rather than me attaching
the whole thing right now, just ask if you want me to post any of that.
Yes, please do "iptables-save > <filename>" and paste the content of the
file into your posting, after changing information that must not be
public (if any). Some other info like kernel version, interfaces (if
more than one)and iptables version may be useful too.
I only have one network interface (not counting lo). Here's the rest of
that info:
# uname -a
Linux box1 2.6.8-2-686-smp #1 SMP Thu May 19 17:27:55 JST 2005 i686 GNU/Linux
# iptables --version
iptables v1.3.1
# iptables-save
# Generated by iptables-save v1.3.1 on Wed Aug 10 13:21:27 2005
*mangle
:PREROUTING ACCEPT [3810743:1593668883]
:INPUT ACCEPT [3810723:1593667323]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [5229526:6297115310]
:POSTROUTING ACCEPT [5233616:6298102388]
-A PREROUTING -d 0.0.0.0/255.0.0.0 -i eth0 -m state --state NEW -j DROP
-A PREROUTING -d 255.255.255.255 -i eth0 -m state --state NEW -j DROP
-A PREROUTING -d 224.0.0.0/240.0.0.0 -i eth0 -m state --state NEW -j DROP
-A PREROUTING -d 0.0.0.0/255.0.0.0 -i eth0 -m state --state NEW -j DROP
-A PREROUTING -d 255.255.255.255 -i eth0 -m state --state NEW -j DROP
-A PREROUTING -d 224.0.0.0/240.0.0.0 -i eth0 -m state --state NEW -j DROP
COMMIT
# Completed on Wed Aug 10 13:21:27 2005
# Generated by iptables-save v1.3.1 on Wed Aug 10 13:21:27 2005
*nat
:PREROUTING ACCEPT [253511:23814701]
:POSTROUTING ACCEPT [23451:1825798]
:OUTPUT ACCEPT [23451:1825798]
COMMIT
# Completed on Wed Aug 10 13:21:27 2005
# Generated by iptables-save v1.3.1 on Wed Aug 10 13:21:27 2005
*filter
:CUST_LOG - [0:0]
:ICMP_CHK - [0:0]
:INPUT DROP [5:272]
:FORWARD DROP [0:0]
:OUTPUT ACCEPT [60966:44974754]
:SANITY_CHK - [0:0]
:SPOOF_CHK - [0:0]
:STATE_CHK - [0:0]
:TCP_CHK - [0:0]
:UDP_CHK - [0:0]
-A CUST_LOG -s 127.0.0.0/255.0.0.0 -i eth0 -j LOG --log-prefix "SPOOF "
--log-level 7 --log-tcp-options --log-ip-options
-A CUST_LOG -s 240.0.0.0/248.0.0.0 -i eth0 -j LOG --log-prefix "SPOOF "
--log-level 7 --log-tcp-options --log-ip-options
-A CUST_LOG -s 248.0.0.0/248.0.0.0 -i eth0 -j LOG --log-prefix "SPOOF "
--log-level 7 --log-tcp-options --log-ip-options
-A CUST_LOG -s 172.16.0.0/255.240.0.0 -i eth0 -j LOG --log-prefix "SPOOF "
--log-level 7 --log-tcp-options --log-ip-options
-A CUST_LOG -s 192.168.0.0/255.255.0.0 -i eth0 -j LOG --log-prefix "SPOOF "
--log-level 7 --log-tcp-options --log-ip-options
-A CUST_LOG -s 10.0.0.12 -i eth0 -j LOG --log-prefix "SPOOF " --log-level 7
--log-tcp-options --log-ip-options
-A CUST_LOG -p tcp -m multiport --dports
23,81,111,123,161,445,515,555,1234,1241,1243,1433,1494,2049,3306 -j LOG
--log-prefix "PROBE " --log-level 7 --log-tcp-options --log-ip-options
-A CUST_LOG -p tcp -m multiport --dports
3128,3389,5631,5632,6635,8080,9055,12345,24452,27374,27573,31337,42484 -j
LOG --log-prefix "PROBE " --log-level 7 --log-tcp-options --log-ip-options
-A CUST_LOG -p udp -m multiport --dports
22,161,1025,3283,5634,5882,28431,31337,31789 -j LOG --log-prefix "PROBE "
--log-level 7 --log-ip-options
-A CUST_LOG -j DROP
-A ICMP_CHK -p icmp -m icmp --icmp-type 0 -m limit --limit 1/sec -j ACCEPT
-A ICMP_CHK -p icmp -m icmp --icmp-type 3/0 -m limit --limit 1/sec -j ACCEPT
-A ICMP_CHK -p icmp -m icmp --icmp-type 3/1 -m limit --limit 1/sec -j ACCEPT
-A ICMP_CHK -p icmp -m icmp --icmp-type 3/3 -m limit --limit 1/sec -j ACCEPT
-A ICMP_CHK -p icmp -m icmp --icmp-type 3/4 -m limit --limit 1/sec -j ACCEPT
-A ICMP_CHK -p icmp -m icmp --icmp-type 11 -m limit --limit 1/sec -j ACCEPT
-A ICMP_CHK -j DROP
-A INPUT -j SPOOF_CHK
-A INPUT -p tcp -j SANITY_CHK
-A INPUT -j STATE_CHK
-A INPUT -s 127.0.0.0/255.255.255.0 -d 127.0.0.0/255.255.255.0 -i lo -m
state --state NEW -j ACCEPT
-A INPUT -p tcp -j TCP_CHK
-A INPUT -p udp -j UDP_CHK
-A INPUT -p icmp -j ICMP_CHK
-A SANITY_CHK -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG FIN,SYN -j DROP
-A SANITY_CHK -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG FIN,PSH -j DROP
-A SANITY_CHK -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG FIN,SYN,ACK
-j DROP
-A SANITY_CHK -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG FIN,SYN,PSH
-j DROP
-A SANITY_CHK -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG FIN,SYN,RST
-j DROP
-A SANITY_CHK -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG
FIN,SYN,RST,PSH -j DROP
-A SANITY_CHK -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG
FIN,SYN,RST,ACK -j DROP
-A SANITY_CHK -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG
FIN,SYN,RST,PSH,ACK -j DROP
-A SANITY_CHK -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG
FIN,SYN,RST,PSH,ACK,URG -j DROP
-A SANITY_CHK -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG FIN -j DROP
-A SANITY_CHK -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG NONE -j DROP
-A SPOOF_CHK -s 127.0.0.0/255.0.0.0 -i eth0 -j CUST_LOG
-A SPOOF_CHK -s 240.0.0.0/248.0.0.0 -i eth0 -j CUST_LOG
-A SPOOF_CHK -s 248.0.0.0/248.0.0.0 -i eth0 -j CUST_LOG
-A SPOOF_CHK -s 172.16.0.0/255.240.0.0 -i eth0 -j CUST_LOG
-A SPOOF_CHK -s 192.168.0.0/255.255.0.0 -i eth0 -j CUST_LOG
-A SPOOF_CHK -s 10.0.0.12 -i eth0 -j CUST_LOG
-A STATE_CHK -m state --state RELATED,ESTABLISHED -j ACCEPT
-A STATE_CHK -m state --state INVALID -j DROP
-A STATE_CHK -p tcp -m state --state NEW -m tcp ! --tcp-flags SYN,RST,ACK
SYN -j DROP
-A TCP_CHK -s 10.0.0.12 -d 10.0.0.12 -p tcp -m tcp --dport 3029:3038 -j ACCEPT
-A TCP_CHK -s 10.0.0.12 -d 10.0.0.12 -p tcp -m tcp --dport 5432 -j ACCEPT
-A TCP_CHK -s 10.0.0.12 -d 10.0.0.12 -p tcp -m tcp --dport 3306 -j ACCEPT
-A TCP_CHK -i eth0 -p tcp -m tcp --dport 113 --tcp-flags SYN,RST,ACK SYN -j
REJECT --reject-with tcp-reset
-A TCP_CHK -i eth0 -p tcp -m tcp --dport 113 --tcp-flags SYN,RST,ACK SYN -j
REJECT --reject-with tcp-reset
-A TCP_CHK -i eth0 -p tcp -m multiport --dports 22,873,80,9618 -m state
--state NEW -m tcp --tcp-flags SYN,RST,ACK SYN -j ACCEPT
-A TCP_CHK -i eth0 -p tcp -m multiport --dports 22,80,873,9618 -m state
--state NEW -m tcp --tcp-flags SYN,RST,ACK SYN -j ACCEPT
-A TCP_CHK -j CUST_LOG
-A UDP_CHK -j CUST_LOG
-A UDP_CHK -s 10.0.0.12 -d 10.0.0.12 -p udp -m udp --dport 5432 -j ACCEPT
-A UDP_CHK -s 10.0.0.12 -d 10.0.0.12 -p udp -m udp --dport 3306 -j ACCEPT
COMMIT
# Completed on Wed Aug 10 13:21:27 2005
Thanks,
Anthony DiSante
http://encodable.com/
http://nodivisions.com/
