The Certified Geek

Sometimes Linux administrator/owners wants to restrict access to the Samba server to specific IP addresses since user authentication is not enabled (because of so reasons). Here is a bash script to use iptables to restrict specific hosts via loop statement.


# Define the interface where Samba listens
IF_INT=eth0
# Define the list of host allowed to connect to the server separate by space and note the /32 subnet
HOSTS="192.168.1.100/32 192.168.1.200/32 192.168.1.201/32"

# This is the FOR loop
for SOURCE in $HOSTS;
do
iptables -A INPUT -i $IF_INT -s $SOURCE -p tcp --dport 445 -j ACCEPT
iptables -A INPUT -i $IF_INT -s $SOURCE -p tcp --dport 139 -j ACCEPT
iptables -A INPUT -i $IF_INT -s $SOURCE -p udp --dport 137 -j ACCEPT
iptables -A INPUT -i $IF_INT -s $SOURCE -p udp --dport 138 -j ACCEPT
done;


Add this to your existing iptables script and your good to go.

I have always been scratching my head whenever I used sudo and the environment variables (env) keep on changing. In my case, I have learned there are two ways to keep/preserve the environment or retain some them when moving into a privilege account (sudo -s).

First method, run

#sudo -s -E

where the -E parameter is meant to presserve the environment.

Second method, save all necessary variables in the current user (not root) shells profile (i.e. for bash its ~/.bashrc) and save these environment variables.

#vi ~/.bashrc
export param1=value1
export param2=value2
#

That’s all to it.

While updating my knowledge with security tools, I manage to stumble upon this “Hackvertor”. It kinda sounded like a convertor in a more hacker term.

For you guys to appreciate this, you should try doing this challenge manually from the Spanner. Then try watching the this video in order to appreciate how it is done with the Hackvertor. Enjoy!