Secure your Ubuntu Server from Flood and Other Attacks Using IPTables and WonderShaper

The following commands use IPTables to prevent common flooding and other miscellaneous malicious attacks. These commands can prevent a Linux server from lagging and spending resources on malformed packets.  Some of these attacks can cause DDoS attacks, so it is best to use these filters and rules.  Use at your own risk. A detailed explanation can be found here.

# Explanations here:
# http://www.cyberciti.biz/tips/linux-iptables-10-how-to-block-common-attack.html
sudo apt-get install iptables
sudo iptables -A INPUT -p tcp ! --syn -m state --state NEW -j DROP
sudo iptables -A INPUT -f -j DROP
sudo iptables -A INPUT -p tcp --tcp-flags ALL ALL -j DROP
sudo iptables -A INPUT -p tcp --tcp-flags ALL NONE -j DROP

If you want to drop ICMP ping requests, click here.

Limiting Download and Upload Speeds / Traffic Globally in Ubuntu

Limiting download and upload speeds globally does not make a server any more secure than before.  However, it can aleviate network lag, which in my opinion ensures availability enhancing security.  In Ubuntu, it's easy to limit the max download and upload speed that can be used on an interface.  It wasn't always this easy, but thanks to a tool called wondershaper, you don't have to worry about any of the complexities.  To install, run the following command:

sudo apt-get install wondershaper  

Now, we need to tell wondershaper to start limiting our max download and upload rate on our particular interface. To see a list of interfaces, type the following command:

ifconfig

To determine what your max download and max upload speed should be, use SpeedTest to run a couple of bandwidth tests using your connection.  With your results, convert the speeds from mbps to kilobits per second.  Use this bandwidth calculator / converter to help you out.  Then, I'd subtract 20-30% of each value, as you want to leave some room between your max speed so that bandwith will still be available to other computers / nodes on the network.

Once you have your speeds, start wondershaper (modifying the example below to fit your needs):

# wondershaper [interface] [max_download_speed_kilobits] [max_upload_speed_kilobits]
sudo wondershaper eth0 8192 2764

Make a backup of the /etc/network/interfaces file:

sudo cp /etc/network/interfaces /etc/network/interfaces.bakup
sudo nano /etc/network/interfaces

To run wondershaper upon boot or startup, edit the /etc/network/interfaces file, and add the following (modify to fit your needs if neccessary):

auto lo
iface lo inet loopback
up /sbin/wondershaper eth0 8192 2764
down /sbin/wondershaper clear eth0

Make sure you change your max download and upload speed in both of the examples.  Settings will now apply when the computer boots into Linux.

Exclude LAN from Speed Limits

WonderShaper does not differentiate between LAN traffic and external traffic by default.  To prevent WonderShaper from limiting LAN network download and upload speeds, install this updated WonderShaper script:

cd ~/Downloads
wget -O wondershaper_exclude_lan.tar.gz www.dinofly.com/files/wondershaper_exclude_lan.tar.gz
tar xzvf wondershaper_exclude_lan.tar.gz
sudo cp -f wondershaper /sbin/wondershaper
sudo chmod +x /sbin/wondershaper
sudo nano /sbin/wondershaper

Find:

#Local Network
LAN_SUBNET=192.168.0.0

Change it to your LAN's main IP address.  For example, if your LAN gateway is 192.168.1.X, change it to:

#Local Network
LAN_SUBNET=192.168.1.0

Another example, if your LAN gateway is 192.168.43.X, change it to:

#Local Network
LAN_SUBNET=192.168.43.0

Save the file and reboot.

Your local area network (LAN) traffic is not filtered, but external traffic is!  Enjoy lag free connections from both the outside and inside while running any type of web server. 

Aspartame and Other Artificial Sweetners in Milk?

The dairy industry is trying to pass a petition to the amend the definition of milk to include artificial sweeteners including Aspartame as ingredients WITHOUT listing them on the label.  How can you possibly even consider redefining the definition of milk?  It's already loaded with hormones that get into the food supply and our bodies.  Haven't you noticed that the next generation continues to grow taller and stronger than previous generations?  I'm pretty sure it's because of the hormones…

Milk should be defined as "the stuff that comes from milking a healthy cow". Nothing else should be added to it.  Thus, I find it disturbing that the dairy industry would even propose such an amendment. 

What's Wrong With Artificial Sweeteners?

Artificial sweeteners have been proven to cause cancer in mice.  New studies also suggest that they cause blood cancers in humans!

What Can We Do To Stop This

Submit a Formal Comment voicing your concerns at the Federal Register using this link:

https://www.federalregister.gov/articles/2013/02/20/2013-03835/flavored-milk-petition-to-amend-the-standard-of-identity-for-milk-and-17-additional-dairy-products

Here's my comment:

“If Aspartame and other artificial sweeteners are used in milk products, I will avoid purchasing these products like the plague and will advise others to do the same. We the people have a fundamental right to know what ingredients have been used in our food products. We are consuming these products, which means we can be affected permanently by what we ingest! We are what we eat, and I don't want to have aspartame or any artificial sweetener in my system. Labels were created to protect consumers from misinformation and ingredients that could cause potential harm to the well-being of people. Therefore, ALL ingredients should be listed on the label including Aspartame and other artificial sweeteners. We have a right to be informed and decide whether or not we want to purchase a product.

Neglecting to list artificial sweeteners as an ingredient raises a red flag. This implies that the safety of artificial sweeteners is controversial and that people would never purchase products containing artificial sweeteners willingly. This is the case, and for once, please do not let the money make the wrong decisions for the people! Passing this amendment could further hurt sales rather than help them. I doubt many people will increase consumption of milk products with the addition of artificial sweeteners. If anything, more people will avoid milk products altogether.

Artificial sweeteners are not natural products and have shown to cause cancer in mice.

Please advise against passing an amendment to the standard identity for milk and 17 additional dairy products.”

Write to your representatives.

We cannot allow this to pass!  If it does, boycott all milk products or be a guinea pig with your health.

Sources:

http://health.yahoo.net/experts/dayinhealth/artificial-sweeteners-milk

https://www.federalregister.gov/articles/2013/02/20/2013-03835/flavored-milk-petition-to-amend-the-standard-of-identity-for-milk-and-17-additional-dairy-products