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VERY URGENT! Firewall Rules HELP (IPTABLES) Redhat 9

Kyle Abrahams
on
2,542 Views
Last Modified: 2013-11-16
NOTE:
192.168.4.1 = webserver  (windows Machine)
192.168.4.2 = Local side address of firewall.
192.168.3.2 = Internet side of address of firewall.


Chain INPUT (policy DROP)
target     prot opt source               destination        
ACCEPT     all  --  anywhere             anywhere          
bad_packets  all  --  anywhere             anywhere          
ACCEPT     all  --  192.168.4.0/24       anywhere          
ACCEPT     all  --  anywhere             192.168.4.255      
ACCEPT     all  --  anywhere             anywhere           state RELATED,ESTABLISHED
tcp_inbound  tcp  --  anywhere             anywhere          
udp_inbound  udp  --  anywhere             anywhere          
icmp_packets  icmp --  anywhere             anywhere          

Chain FORWARD (policy DROP)
target     prot opt source               destination        
bad_packets  all  --  anywhere             anywhere          
tcp_outbound  tcp  --  anywhere             anywhere          
udp_outbound  udp  --  anywhere             anywhere          
ACCEPT     all  --  anywhere             anywhere          
ACCEPT     all  --  anywhere             anywhere           state RELATED,ESTABLISHED
ACCEPT     tcp  --  anywhere             192.168.4.1        tcp dpt:http
LOG        all  --  anywhere             anywhere           limit: avg 3/min burst 3 LOG level warning prefix `FORWARD packet died: '

Chain OUTPUT (policy DROP)
target     prot opt source               destination        
DROP       icmp --  anywhere             anywhere           state INVALID
ACCEPT     all  --  192.168.4.2          anywhere          
ACCEPT     all  --  anywhere             anywhere          
ACCEPT     all  --  Linux-Firewall       anywhere          
ACCEPT     all  --  anywhere             anywhere          
ACCEPT     all  --  anywhere             anywhere          
LOG        all  --  anywhere             anywhere           limit: avg 3/min burst 3 LOG level warning prefix `OUTPUT packet died: '

Chain bad_packets (2 references)
target     prot opt source               destination        
LOG        all  --  anywhere             anywhere           state INVALID LOG level warning prefix `Invalid packet: '
DROP       all  --  anywhere             anywhere           state INVALID
bad_tcp_packets  tcp  --  anywhere             anywhere          
RETURN     all  --  anywhere             anywhere          

Chain bad_tcp_packets (1 references)
target     prot opt source               destination        
RETURN     tcp  --  anywhere             anywhere          
LOG        tcp  --  anywhere             anywhere           state NEW tcp flags:!SYN,RST,ACK/SYN LOG level warning prefix `New not syn:'
DROP       tcp  --  anywhere             anywhere           state NEW tcp flags:!SYN,RST,ACK/SYN
RETURN     tcp  --  anywhere             anywhere          

Chain icmp_packets (1 references)
target     prot opt source               destination        
ACCEPT     icmp --  anywhere             anywhere           icmp time-exceeded
RETURN     icmp --  anywhere             anywhere          

Chain icmp_pakets (0 references)
target     prot opt source               destination        

Chain tcp_inbound (1 references)
target     prot opt source               destination        
ACCEPT     tcp  --  anywhere             anywhere           tcp dpt:http
ACCEPT     tcp  --  anywhere             anywhere           tcp dpt:https
#35 shouldn't be in here, I need to remove.
ACCEPT     tcp  --  anywhere             anywhere           tcp dpt:35  
ACCEPT     tcp  --  anywhere             anywhere           tcp dpt:smtp
ACCEPT     tcp  --  anywhere             anywhere           tcp dpt:pop3
ACCEPT     tcp  --  anywhere             anywhere           tcp dpt:imap
ACCEPT     tcp  --  anywhere             anywhere           tcp dpt:ssh
RETURN     tcp  --  anywhere             anywhere          

Chain tcp_outbound (1 references)
target     prot opt source               destination        
REJECT     tcp  --  anywhere             anywhere           tcp dpt:irc reject-with icmp-port-unreachable
REJECT     tcp  --  anywhere             anywhere           tcp dpt:telnet reject-with icmp-port-unreachable
REJECT     tcp  --  anywhere             anywhere           tcp dpt:nntp reject-with icmp-port-unreachable
REJECT     tcp  --  anywhere             anywhere           tcp dpt:ftp reject-with icmp-port-unreachable
REJECT     tcp  --  anywhere             anywhere           tcp dpt:ftp-data reject-with icmp-port-unreachable
#5190 AIM, 4443 Yahoo, 1863 MSN
REJECT     tcp  --  anywhere             anywhere           tcp dpt:5190 reject-with icmp-port-unreachable
REJECT     tcp  --  anywhere             anywhere           tcp dpt:4443 reject-with icmp-port-unreachable
REJECT     tcp  --  anywhere             anywhere           tcp dpt:1863 reject-with icmp-port-unreachable
ACCEPT     tcp  --  anywhere             anywhere          

Chain udp_inbound (1 references)
target     prot opt source               destination        
#drop netbios noise.
DROP       udp  --  anywhere             anywhere           udp dpt:netbios-ns
DROP       udp  --  anywhere             anywhere           udp dpt:netbios-dgm
RETURN     udp  --  anywhere             anywhere          

Chain udp_outbound (1 references)
target     prot opt source               destination        
REJECT     udp  --  anywhere             anywhere           udp dpt:4000 reject-with icmp-port-unreachable
ACCEPT     udp  --  anywhere             anywhere          

 
checking logs:

"New Not Syn: " In=eth0 (192.168.3.2.),   out=eth0, SRC= 192.168.4.1, dst = 192.168.3.1(machine I'm trying to access from),
LEN = 48 TOS=0x00 TTL = 127 ID = 1527 DF PROTO = TCP SPT = 80 DPT = 3492 WINDOW = 64240 RES=0x00 ACK SYN URGP

This is coming from the bad_tcp_packets chain.  It looks like the ACK and SYN flags are set, so why is it dropping this packet?

VERY URGENT any and all help greatly appreciated.

Thanks.

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