Hack The Sec-Leading Resource Of Linux Tutorial: SSH

COPY PUTTY (SSH) SESSIONS TO NEW OR OTHER COMPUTER

<p> <b><u><span style="font-size: large;">COPY PUTTY (SSH) SESSIONS TO NEW/OTHER COMPUTER</span></u></b></p><p><span face="Lato, sans-serif" style="color: #2b2b2b; font-size: 16px;"><br /></span></p><p><span face="Lato, sans-serif" style="color: #2b2b2b; font-size: 16px;">I’m a huge fan of putty – available for download at:</span><span face="Lato, sans-serif" style="color: #2b2b2b; font-size: 16px;"> </span><a href="https://www.chiark.greenend.org.uk/~sgtatham/putty/latest.html" style="border: 0px; color: #24890d; font-family: inherit; font-size: 16px; font-style: inherit; font-weight: inherit; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Download PuTTY: latest release (0.78) (greenend.org.uk)</a></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhiw6DmAPtJ_KtkLaWWcNiyFLTjlTgHEIc21VnBrMUjL4BZtlyMXXsjeMU7lBX91pK0N-blwlF02TCDRhaXA2kdojQFqOetYjidlc-nMYXzFoU0oEdkVFLeucqFLMuaSfVlD0vEDBxPMAyvMiUsAvzqiBgxZB5pLGhr-TZEhRWzMV5rTqYtpkVz92M/s1200/PuTTY_Icon_upstream.svg.png" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;"><img border="0" data-original-height="1200" data-original-width="1200" height="212" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhiw6DmAPtJ_KtkLaWWcNiyFLTjlTgHEIc21VnBrMUjL4BZtlyMXXsjeMU7lBX91pK0N-blwlF02TCDRhaXA2kdojQFqOetYjidlc-nMYXzFoU0oEdkVFLeucqFLMuaSfVlD0vEDBxPMAyvMiUsAvzqiBgxZB5pLGhr-TZEhRWzMV5rTqYtpkVz92M/w212-h212/PuTTY_Icon_upstream.svg.png" width="212" /></a></div><br /><p><br /></p><p style="border: 0px; color: #2b2b2b; font-family: Lato, sans-serif; font-size: 16px; margin: 0px 0px 24px; outline: 0px; padding: 0px; vertical-align: baseline;">Over time, I tend to accumulate a large number of saved “sessions” that I find it useful to either move to a new computer, or save/backup. He</p><p style="border: 0px; color: #2b2b2b; font-family: Lato, sans-serif; font-size: 16px; margin: 0px 0px 24px; outline: 0px; padding: 0px; vertical-align: baseline;"><code style="border: 0px; font-family: monospace, serif; font-size: 15px; font-style: inherit; font-weight: inherit; hyphens: none; line-height: 1.6; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">regedit /ea c:\Users\mark\dropbox\_mark\puttycopy.reg HKEY_CURRENT_USER\Software\SimonTatham\PuTTY</code></p><p style="border: 0px; color: #2b2b2b; font-family: Lato, sans-serif; font-size: 16px; margin: 0px 0px 24px; outline: 0px; padding: 0px; vertical-align: baseline;">Copied that puttycopy.reg to the new drive/computer.</p><p style="border: 0px; color: #2b2b2b; font-family: Lato, sans-serif; font-size: 16px; margin: 0px 0px 24px; outline: 0px; padding: 0px; vertical-align: baseline;">To add the saved sessions, just double clicked on that .reg file on the new computer.</p>

COPY PUTTY (SSH) SESSIONS TO NEW OR OTHER COMPUTER

COPY PUTTY (SSH) SESSIONS TO NEW/OTHER COMPUTER I’m a huge fan of putty – available for download at: Download PuTTY: latest release (0.7...

Reverse SSH Tunneling

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<u><span style="color: #990000;">Reverse SSH Tunneling</span></u></h1>
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<span style="color: #333333; font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">In this tutorial we will covering how to bypass these restrictions using a technique called Rerverse SSH Tunneling.</span></span></div>
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<span style="color: red; font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">Note: This tutorial assumes you are using <a href="http://www.hackthesec.co.in/search/label/Ubuntu">Ubuntu</a>. The steps however are expected to work for other Linux distribution.</span></span></div>
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<b><span style="color: #0b5394;"><u>Prerequisites:</u></span></b></div>
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<ul style="font-family: verdana, geneva, sans-serif; font-size: 15px; line-height: 26px; text-align: left;">
<li>An Ubuntu server instance.</li>
<li>A SSH Client on your local machine.</li>
</ul>
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<span style="font-size: 15px; line-height: 26px;"><b><u><span style="color: #0b5394;">Step 1: Configuring SSH daemon on your server:</span></u></b></span></div>
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<span style="font-size: 15px; line-height: 26px;">By default, <a href="http://www.hackthesec.co.in/search/label/SSH">SSH </a>daemon is only listening on <span style="color: red;">127.0.0.1</span>, so we won’t be able to access to our forwarded ports from outside. To get it listen on the interface connected to Internet we must enable <span style="color: red;">GatewayPorts </span>option in <a href="http://www.hackthesec.co.in/search/label/SSH">SSH </a>server's configuration.</span></div>
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<span style="font-size: 15px; line-height: 26px;">Open <b>/etc/ssh/sshd_config</b> using your favorite text editor.</span></div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-size: large;"><span style="line-height: 20.8px;">nano /etc/ssh/sshd_config</span></span></pre>
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<span style="font-size: 15px; line-height: 26px;">Then add <b><span style="color: red;">GatewayPorts yes</span></b> at the bottom of the file.</span></div>
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<span style="font-size: 15px; line-height: 26px;">After saving the file, restart the SSH daemon:</span></div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-size: large;"><span style="line-height: 20.8px;">service ssh restart</span></span></pre>
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<span style="color: #0b5394; font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;"><b><u>Step 2: Tunneling:</u></b></span></span></div>
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<span style="font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">If your home computer runs Linux, you’ll need to use the ssh command as follows:</span></span></div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-size: large;"><span style="line-height: 20.8px;">ssh -R [Port to forward to on your VPS]:localhost:[Port to forward on your local machine] [VPS IP]</span></span></pre>
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<span style="font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">Or if you have installed Microsoft Windows on your machine then you have to install <a href="http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html">plink</a> and connect as shows below:</span></span></div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-size: large;"><span style="line-height: 20.8px;">plink -R [Port to forward to on your VPS]:localhost:[Port to forward on your local machine] [VPS IP]</span></span></pre>
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<span style="font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">In this example, we’re forwarding port <b>19132</b> which is open on your at-home machine to port <b>80 </b>on your remote server (assuming your server's IP Address is <b>192.168.0.1</b>).</span></span></div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-size: large;"><span style="line-height: 20.8px;">ssh -R 80:localhost:19132 192.168.0.1</span></span></pre>
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<span style="font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">This will allow you to access your at-home machine from a remote location by connecting to <b>192.168.0.1:80</b></span></span></div>
<div style="font-family: verdana, geneva, sans-serif; font-size: 15px; line-height: 26px;">
<a href="http://www.hackthesec.co.in/">www.hackthesec.co.in</a></div>
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</div>

Reverse SSH Tunneling

Reverse SSH Tunneling In this tutorial we will covering how to bypass these restrictions using a technique called Rerverse SSH Tunneling...

Setup SFTP-only User Accounts on CentOS 7

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<span style="color: #990000; font-size: large;"><u>Setup SFTP-only User Accounts on CentOS</u></span></h1>
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<span style="color: #333333; font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">The SSH File Transfer Protocol (also Secure File Transfer Protocol, or SFTP) is a network protocol that provides file access, file transfer, and file management over any reliable data stream. It was designed by the Internet Engineering Task Force (IETF) as an extension of the Secure Shell protocol (<a href="http://www.hackthesec.co.in/search/label/SSH">SSH</a>) version 2.0 to provide secure file </span></span></div>
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<span style="color: #333333; font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">transfer capabilities. The IETF Internet Draft states that, even though this protocol is described in the context of the SSH-2 protocol, it could be used in a number of different applications, such as secure file transfer over Transport Layer Security (TLS) and transfer of management information in <a href="http://www.hackthesec.co.in/search/label/VPN">VPN </a>applications.</span></span></div>
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<span style="color: #0b5394; font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;"><b><u>Step 1: Create a dedicated sFTP group and a dedicated sFTP user</u></b></span></span></div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="font-size: large;"><span style="line-height: 20.8px;"><span style="color: white;">groupadd sftpusers
</span><span style="color: orange;">useradd -G sftpusers -s /sbin/nologin user1
</span><span style="color: white;">passwd user1</span></span></span></pre>
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<span style="color: #333333; font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">Here, the group <b>sftpusers </b>is a dedicated sFTP group, the user <b>user1 </b>is a dedicated sFTP user which is forbidden to log in using SSH.</span></span></div>
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<span style="color: #0b5394; font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;"><b><u>Step 2: Modify the configuration of the sshd service</u></b></span></span></div>
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<span style="color: #333333; font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">Open the configuration file of the sshd service:</span></span></div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-size: large;"><span style="line-height: 20.8px;">vi /etc/ssh/sshd_config</span></span></pre>
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<span style="color: #333333; font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">Find the line:</span></span></div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: orange; font-size: large;"><span style="line-height: 20.8px;">Subsystem sftp /usr/libexec/openssh/sftp-server</span></span></pre>
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<span style="color: #333333; font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">Replace it with:</span></span></div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="font-size: large;"><span style="line-height: 20.8px;"><span style="color: white;">Subsystem </span><span style="color: orange;">sftp internal-sftp</span></span></span></pre>
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<span style="color: #333333; font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">Append the following lines to the end of the file. The group name <b>sftpusers </b>should be the same as the one you specified earlier.</span></span></div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="font-size: large;"><span style="line-height: 20.8px;"><span style="color: white;">Match Group sftpusers
X11Forwarding no
AllowTcpForwarding no
</span><span style="color: orange;">ChrootDirectory %h
</span><span style="color: white;">ForceCommand internal-sftp</span></span></span></pre>
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<span style="color: #333333; font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">Save and quit: use :wq</span></span></div>
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<span style="color: #333333; font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">Restart the sshd service to put your changes into effect.</span></span></div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="font-size: large;"><span style="line-height: 20.8px;"><span style="color: white;">systemctl </span><span style="color: orange;">restart sshd.service</span></span></span></pre>
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<b><u><span style="color: #0b5394;">Step 3: Create a dedicated directory for the sFTP-only user</span></u></b></div>
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You need to specify a directory for the sFTP-only user and make sure that this user can only play around in this directory:</div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="font-size: large;"><span style="line-height: 20.8px;"><span style="color: white;">chown -R root /home/user1
chmod -R 755 /home/user1
</span><span style="color: orange;">mkdir /home/user1/files
</span><span style="color: white;">chown user1. /home/user1/files</span></span></span></pre>
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<span style="color: #333333; font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">Now, the user <b>user1 </b>can only upload and/or download files in the directory <b>/home/user1/files</b>, he or she can never touch other users' files.</span></span></div>
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<span style="font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;"><div>
<b><u><span style="color: #0b5394;">Step 4: Create more sFTP-only users</span></u></b></div>
<div style="color: #333333;">
If you need more sFTP-only users, you can create them in the same fashion:</div>
</span></span></div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="font-size: large;"><span style="line-height: 20.8px;"><span style="color: orange;">useradd -G sftpusers -s /sbin/nologin user2
passwd user2</span><span style="color: white;">
chown -R root /home/user2
chmod -R 755 /home/user2
mkdir /home/user2/files
chown user2. /home/user2/files</span></span></span></pre>
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<span style="color: #333333; font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">That's it. Each user account created in this fashion will be denied if you use it to log in the system. These user accounts can be used only in sFTP programs.</span></span></div>
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<span style="color: #333333; font-family: verdana, geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;"><a href="http://www.hackthesec.co.in/">www.hackthesec.co.in</a></span></span></div>
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Setup SFTP-only User Accounts on CentOS 7

Setup SFTP-only User Accounts on CentOS The SSH File Transfer Protocol (also Secure File Transfer Protocol, or SFTP) is a network protoc...

How To Setup SSH Keys

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<span style="color: red; font-size: x-large;"><u>Setup SSH Keys</u></span></h1>
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<span style="color: #222222; font-family: Verdana, Geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">SSH keys are by far the most secure way of logging into your cloud server via SSH. Passwords can be eventually cracked using brute-force attacks if they are too easy. If they are complex passwords, they become very hard to remember and writing them down defeats the purpose of a password.</span></span></div>
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<span style="color: #222222; font-family: Verdana, Geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;"><b>SSH </b>keys are nearly impossible to decipher using a brute force attack. If you generate an <a href="http://www.hackthesec.co.in/search/label/SSH">SSH key</a>, you will get a pair of two very long string of characters: a public and private key.</span></span></div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgB-K6lGsBayShpawfyJUyK-w_T51_O2aLcOec6JqeyVBVxXPjj0nI2Cip35_7ga-VRAx8sR10WxPBTb8_CEk1t46cedsUG3ZEc_I2G9EWYzmQ6TFMYjhoxyy9cXPxzdseba1rHUiD4DX9H/s1600/ssh_keys_setup-www.hackthesec.co.in.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgB-K6lGsBayShpawfyJUyK-w_T51_O2aLcOec6JqeyVBVxXPjj0nI2Cip35_7ga-VRAx8sR10WxPBTb8_CEk1t46cedsUG3ZEc_I2G9EWYzmQ6TFMYjhoxyy9cXPxzdseba1rHUiD4DX9H/s1600/ssh_keys_setup-www.hackthesec.co.in.jpg" /></a></div>
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<span style="color: #222222; font-family: Verdana, Geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;"><br /></span></span></div>
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<span style="color: #222222; font-family: Verdana, Geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">Public keys are stored on the server that you’re trying to login to, the only possible tool which could unlock this public key is the private key which will be stored with you. SSH uses this to verify your identity by making sure that your private key can unlock the public key installed on the server.</span></span></div>
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<span style="font-family: Verdana, Geneva, sans-serif;"><span style="line-height: 26px;"><div>
<b><u><span style="color: #0b5394; font-size: large;">Create the <a href="http://www.hackthesec.co.in/search/label/SSH">SSH</a> key pairs</span></u></b></div>
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The first step is to generate the combination of the public and private key. This can easily be done by opening a terminal window on the machine you will be using to access the remote server (most likely your own workstation).</div>
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In this example, we will be using RSA keys. The default values should be the correct ones, so you can simply just press enter to accept the default values. However, you may choose to add a passphrase for additional protection.</div>
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The passphrase is a password which unlocks your private key, which means that in order for someone to gain access, they must have both the private key and your passphrase. You can opt to not using a passphrase if you do not want to type a password each time.</div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; text-align: left; vertical-align: baseline;"><div style="text-align: justify;">
<span style="color: lime; font-family: Courier New, Courier, monospace; font-size: large;"><span style="line-height: 15.6px;">[root@hackthesec]# ssh-keygen -t rsa</span></span></div>
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<span style="color: white; font-family: Courier New, Courier, monospace; font-size: large;"><span style="line-height: 15.6px;">Generating public/private rsa key pair.</span></span></div>
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<span style="color: white; font-family: Courier New, Courier, monospace; font-size: large;"><span style="line-height: 15.6px;">Enter file in which to save the key (/Users/user/.ssh/id_rsa): test</span></span></div>
<span style="color: white; font-family: Courier New, Courier, monospace; font-size: large;"><span style="line-height: 15.6px;">Enter passphrase (empty for no passphrase):
</span></span><div style="text-align: justify;">
<span style="color: white; font-family: Courier New, Courier, monospace; font-size: large;"><span style="line-height: 15.6px;">Your identification has been saved in /Users/user/.ssh/id_rsa.</span></span></div>
<span style="color: white; font-family: Courier New, Courier, monospace; font-size: large;"><span style="line-height: 15.6px;">Enter same passphrase again:
</span></span><div style="text-align: justify;">
<span style="color: lime; font-family: Courier New, Courier, monospace; font-size: large;"><span style="line-height: 15.6px;">Your public key has been saved in /Users/user/.ssh/id_rsa.pub.</span></span></div>
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<span style="color: #222222; font-family: Verdana, Geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">As you see by the results of the command, we now have an <b>id_rsa</b> and <b>id_rsa.pub</b> file which contain your private and public key respectively. We can now distribute this public key to servers where we would like to use public key authentication.</span></span></div>
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<span style="font-family: Verdana, Geneva, sans-serif;"><span style="line-height: 26px;"><div>
<b><u><span style="color: #0b5394; font-size: large;">Installing Public Key</span></u></b></div>
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The SSH software stack comes with a useful little program called ssh-copy-id which facilitates the installation of <b>SSH keys</b> on your target server. All you have to do is run the following, replacing user and host by the appropriate information for your remote host.</div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; text-align: left; vertical-align: baseline;"><div style="text-align: justify;">
<span style="font-size: large;"><span style="color: white; font-family: Courier New, Courier, monospace;"><span style="line-height: 15.6px;">[root@hackthesec]# </span></span><span style="line-height: 15.6px; text-align: left;"><span style="color: lime; font-family: Courier New, Courier, monospace;">ssh-copy-id</span><span style="color: white; font-family: Courier New, Courier, monospace;"> user@host</span></span></span></div>
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<span style="color: #222222; font-family: Verdana, Geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">If your operating system does not have that command included, you can run the following command instead. If you get an error about your<b> .ssh</b> folder not existing, you should login to your server and create that folder by running <b>mkdir ~/.ssh.</b></span></span></div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; text-align: left; vertical-align: baseline;"><div style="text-align: left;">
<span style="font-size: large;"><span style="color: white; font-family: Courier New, Courier, monospace;"><span style="line-height: 15.6px;">[root@hackthesec]# </span></span><span style="line-height: 15.6px; text-align: left;"><span style="color: lime; font-family: Courier New, Courier, monospace;">cat /Users/user/.ssh/id_rsa.pub</span><span style="color: white; font-family: Courier New, Courier, monospace;"> | ssh user@host "cat >> ~/.ssh/authorized_keys"</span></span></span></div>
</pre>
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<span style="color: #222222; font-family: Verdana, Geneva, sans-serif;"><span style="font-size: 15px; line-height: 26px;">From now on, you can SSH to the server and you will note that your server will not ask for any passwords at all. The only thing it may ask for is your passphrase if you have configured one for your private key.</span></span></div>
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<a href="http://www.hackthesec.co.in/">hackthesec.co.in</a></div>
</div>

How To Setup SSH Keys

Setup SSH Keys SSH keys are by far the most secure way of logging into your cloud server via SSH. Passwords can be eventually cracked u...

SSH Management Console Script

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<h1 class="entry-title" style="background-color: white; box-sizing: border-box; font-family: Roboto, sans-serif; font-size: 40px; font-weight: 400; line-height: 50px; margin: 0px 0px 7px; word-wrap: break-word;">
<u><i><span style="color: red;">SSH Management Console Script</span></i></u></h1>
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SSH Management Console Script naming “sshc” is a simple program that you can use it instead of putty connection manager , securecrt , PAC manager or any SSH manager that installed on linux distributions .</div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjU9lD35mRjdk0vQoKaKF-uY7WWInVznmVen5dWzVP4LSGbddeQO3ZuWYJ_oNUzIM6G3khTOMXUlTljDQepBqgXWi5w2CK0Lw8sKuWa-iL7oo2x-2YsYTPQCWfnlg_qbXjtDs6k3XeWNm31/s1600/ssh_management_console_www.hackthesec.co.in.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjU9lD35mRjdk0vQoKaKF-uY7WWInVznmVen5dWzVP4LSGbddeQO3ZuWYJ_oNUzIM6G3khTOMXUlTljDQepBqgXWi5w2CK0Lw8sKuWa-iL7oo2x-2YsYTPQCWfnlg_qbXjtDs6k3XeWNm31/s1600/ssh_management_console_www.hackthesec.co.in.jpg" /></a></div>
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This program is so simple, secure and accessible from shell . I mean You can install it on your server for connection to another servers from a linux server .</div>
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<strong style="box-sizing: border-box;"><span style="box-sizing: border-box; color: red;">How Can I Install this Program on My Server ?</span></strong></div>
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At the First We Must Wget sshc on our server . ( in this case my operating system is centos 6.7 )</div>
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At The Next Step According to README file We Should install <span class="short_text" id="result_box" lang="en" style="box-sizing: border-box;">Prerequisite</span>s that listed Bellow :</div>
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0. openssl<br style="box-sizing: border-box;" />1. sshpass<br style="box-sizing: border-box;" />2. mkdir<br style="box-sizing: border-box;" />3. cp<br style="box-sizing: border-box;" />4. rm<br style="box-sizing: border-box;" />5. whoami<br style="box-sizing: border-box;" />6. ping<br style="box-sizing: border-box;" />7. curl<br style="box-sizing: border-box;" />8. ssh<br style="box-sizing: border-box;" />9. echo<br style="box-sizing: border-box;" />10. cat<br style="box-sizing: border-box;" />11. joe</div>
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<u><span style="color: #0b5394;">Install dependency tools </span></u></div>
<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: #333333; font-size: medium; line-height: 19.2px;"><span style="background-color: transparent; line-height: 15.6px;"><span style="color: white; font-family: 'courier new', courier, monospace;">[root@server /]#</span></span><span style="color: white; font-family: 'courier new', courier, monospace;"><span style="line-height: 15.6px;"> </span></span></span><span style="background-color: transparent; line-height: 15.6px;"><span style="color: white; font-family: courier new, courier, monospace; font-size: medium;">yum -y install openssl sshpass curl ssh joe</span></span></pre>
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Then We Must install sshc with install.sh :</div>
<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-family: courier new, courier, monospace; font-size: medium;"><span style="line-height: 15.6px;">[root@server sshc-master]# chmod +x install.sh
[root@server sshc-master]# ./install.sh
</span></span><span style="color: white;">Usage:
        sudo ./install.sh -i [for install program]
        sudo ./install.sh -u [for uninstall program]
        sudo ./install.sh -c [check dependencies on system]</span>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgFg9MHVorfIuWqLR5DRw1IhqwF9618cxXjUj5S0qo22BjnZcpFELcMJOgEe4M3tNociiVchA9U63nFxP8WaZLKwY6U25KwI72ZjiRuVAPa8NsAAHcB8I8dUt_bnCdJidK-3w48dT4Jp-MU/s1600/installation_www.hackthesec.co.in.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgFg9MHVorfIuWqLR5DRw1IhqwF9618cxXjUj5S0qo22BjnZcpFELcMJOgEe4M3tNociiVchA9U63nFxP8WaZLKwY6U25KwI72ZjiRuVAPa8NsAAHcB8I8dUt_bnCdJidK-3w48dT4Jp-MU/s1600/installation_www.hackthesec.co.in.png" /></a></div>
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<strong style="box-sizing: border-box;"><span style="box-sizing: border-box; color: red;"><u>Checking Dependencies</u></span></strong></div>
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We can Check Dependencies with -c switch :</div>
<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-family: courier new, courier, monospace; font-size: medium;"><span style="line-height: 15.6px;">[root@server sshc-master]# ./install.sh -c
[+] ------------------------------------------------ [+]
[+] check dependencies on system:
[+] whoami found
[+] sleep found
[+] cat found
[+] head found
[+] tail found
[+] cut found
[+] expr found
[+] curl found
[+] nano found
[+] openssl found
[+] sshpass found
[+] ------------------------------------------------ [+]
[root@server sshc-master]#
</span></span></pre>
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<span style="color: white; font-family: courier new, courier, monospace; font-size: medium;"><span style="line-height: 15.6px;"><br /></span></span></div>
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<span style="background-color: white; color: #222222; font-family: Verdana, Geneva, sans-serif; font-size: 15px; line-height: 26px;">after install We Should Run “sshc” command to complete sshc database (defaul password is ‘sshc’)</span></div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEifDaxK4qEy_MiJJxmz3miOZsxlLitZo1YgioTm-ZevwppmYJtIoAXUlw-dVss6IEs4RL1_f99GbImVDGMElGM73uIyC0vh4szBFKv9uVZRDrpG5Gs0piAMLf_OX8PeXTI-KN5SW6TPR2vv/s1600/sshc_setup_www.hackthesec.co.in.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEifDaxK4qEy_MiJJxmz3miOZsxlLitZo1YgioTm-ZevwppmYJtIoAXUlw-dVss6IEs4RL1_f99GbImVDGMElGM73uIyC0vh4szBFKv9uVZRDrpG5Gs0piAMLf_OX8PeXTI-KN5SW6TPR2vv/s1600/sshc_setup_www.hackthesec.co.in.png" /></a></div>
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<span style="background-color: white; color: #222222; font-family: Verdana, Geneva, sans-serif; font-size: 15px; line-height: 26px;">after typing password we must select 0 for editing database :</span></div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-family: courier new, courier, monospace; font-size: medium;"><span style="line-height: 15.6px;">[+] Enter password:
 0) Edite Database
[+] Select your server/option or type quit for exit:0
</span></span></pre>
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<span style="background-color: white; color: #222222; font-family: Verdana, Geneva, sans-serif; font-size: 15px; line-height: 26px;">default editor of sshc database is joe , for saving settings we should press ctrl+k+x</span></div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjMJ0b0pBBjEqd_Q2guLBBS6aNMnme3jJGopZ_HE9lWmwlFud1PahThXMGl9u0upu3YkUW-z8PSprWl2EhMUdxoxySTAoQD1DC92Jy4GYqQ24IMRr7YSsX6yFDs6VPlgRuNlRpNA-KlTPpU/s1600/sshc_database.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjMJ0b0pBBjEqd_Q2guLBBS6aNMnme3jJGopZ_HE9lWmwlFud1PahThXMGl9u0upu3YkUW-z8PSprWl2EhMUdxoxySTAoQD1DC92Jy4GYqQ24IMRr7YSsX6yFDs6VPlgRuNlRpNA-KlTPpU/s1600/sshc_database.png" /></a></div>
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Note : Add Your Servers According to the above Example .</div>
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After Save, Console shows it :</div>
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<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-family: courier new, courier, monospace; font-size: medium;"><span style="line-height: 15.6px;">[+] ------------------------------------------------------------------- [+]
[+] Programming and idea by : E2MA3N [Iman Homayouni]
[+] License : GPL v3.0
[+] sshc v4.0

[+] Enter password:

0) Edite Database

[+] Select your server/option or type quit for exit: 0
[+] encrypt new database, Please type your password:
[+] Done, New database saved and encrypted
[+] ------------------------------------------------------------------- [+]
[root@server ~]#
</span></span></pre>
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<span style="background-color: white; color: #222222; font-family: Verdana, Geneva, sans-serif; font-size: 15px; line-height: 26px;">The program requests default password for encrypting database file . lets run again sshc for connecting our server :</span></div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjbYJ2wTnZNFGJQMMxsRlmi9U5RNVjjV0upFvcoYqi1qUn9K-lCuh_yRKZzBa-FxfcNAHt-jOORnkw_QOISaRZKC44jIsDrgSGUovzZStOA5gYaHIvecomqCgyZsBgarYXEYlzIzACvdb7l/s1600/sshc_connection_check_www.hackthesec.co.in.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjbYJ2wTnZNFGJQMMxsRlmi9U5RNVjjV0upFvcoYqi1qUn9K-lCuh_yRKZzBa-FxfcNAHt-jOORnkw_QOISaRZKC44jIsDrgSGUovzZStOA5gYaHIvecomqCgyZsBgarYXEYlzIzACvdb7l/s1600/sshc_connection_check_www.hackthesec.co.in.png" /></a></div>
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<span style="background-color: white; color: #222222; font-family: Verdana, Geneva, sans-serif; font-size: 15px; line-height: 26px;">We Have 3 Options for Direct Connection to server or Accept our public ip on server firewall ( iptables ) or 1 and 2 options in 3 </span></div>
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<span style="background-color: white; color: #222222; font-family: Verdana, Geneva, sans-serif; font-size: 15px; line-height: 26px;">This is Encrypted Database File :</span></div>
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<pre style="background-color: #f1f1f1; border-radius: 0px; border: none; box-sizing: border-box; color: #222222; font-family: monospace, monospace; font-size: 15px; line-height: 26px; margin-top: 24px; overflow: auto; padding: 4px 10px;">[root@server sshc-master]# cat /etc/sshc/sshc.database.en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[root@server sshc-master]#</pre>
</div>
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<span style="font-size: large;"><a href="https://github.com/e2ma3n/sshc" target="_blank">Download The Script From Here</a></span></div>
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<a href="http://www.hackthesec.co.in/">www.hackthesec.co.in</a></div>
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<br /></div>
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<span style="font-size: medium;"><span style="color: white; font-family: 'courier new', courier, monospace;"><span style="line-height: 15.6px;"><br /></span></span></span></div>
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SSH Management Console Script

SSH Management Console Script SSH Management Console Script naming “sshc” is a simple program that you can use it instead of putty conne...

How To Deploy a Hugo Site to Production with Git Hooks on Ubuntu 14.04

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<h1 class="entry-title" itemprop="headline" style="background-color: #fdfdfd; box-sizing: border-box; color: #333333; font-family: proxima-nova, 'Helvetica Neue', Helvetica, Arial, sans-serif; line-height: 1.1; margin: 21px 0px 0px;">
<span style="font-size: x-large;"><u><i>Deploy a Hugo Site to Production with Git Hooks on Ubuntu</i></u></span></h1>
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<span style="background-color: #fdfdfd; font-size: 18px; line-height: 28px;"><span style="font-family: Georgia, Times New Roman, serif;">Hugo is an open source static site generator. Static site generators build a web page the moment you’re creating or editing new content. It comes with a watch mode which automatically refreshes web pages when editing them. Hugo was started as a side project by Steve Francia and today its community has more than 165 contributions, 35 themes and thousands of users. The biggest advantage of using static is that the websites are incredibly fast especially when compared to sites that carry all the burden of a heavyweight content management system.</span></span></div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjVj0jjZ5vB5_gji1LGruqcLJmNWshZ8sPw6nrMR7b1zLRvB8VLjqXA_VVwViOdyoDkReYoJPrClZUFhpQPdGhCcmAAAGFKNCzsyFb8cKwt4RK7wVWjFU0g4K0uzPcg6WoDLmAvb1SrEtGR/s1600/hugo_www.hackthesec.co.in.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjVj0jjZ5vB5_gji1LGruqcLJmNWshZ8sPw6nrMR7b1zLRvB8VLjqXA_VVwViOdyoDkReYoJPrClZUFhpQPdGhCcmAAAGFKNCzsyFb8cKwt4RK7wVWjFU0g4K0uzPcg6WoDLmAvb1SrEtGR/s1600/hugo_www.hackthesec.co.in.jpg" /></a></div>
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<span style="background-color: #fdfdfd; font-size: 18px; line-height: 28px;"><span style="font-family: Georgia, Times New Roman, serif;"><br /></span></span></div>
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<h2 style="background-color: #fdfdfd; box-sizing: border-box; font-family: proxima-nova, 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 32px; font-weight: 500; line-height: 1.1; margin-bottom: 10.5px; margin-top: 21px;">
<span style="box-sizing: border-box;"><span style="color: #0b5394;"><u>Pre-requisites</u></span></span></h2>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">In order to deploy Hugo site on production, you must first setup your development server with Hugo on <a href="http://www.hackthesec.co.in/search/label/ubuntu-14.04" target="_blank">Ubuntu 14.04</a>. Then build a new production server with <a href="http://www.hackthesec.co.in/search/label/Ubuntu" target="_blank">Ubuntu</a> 14.04 installed. Once you have access to both development and production servers, perform the following tasks to achieve your target deployment on Hugo Site with Git Hooks.</span></span></div>
<h2 style="background-color: #fdfdfd; box-sizing: border-box; font-family: proxima-nova, 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 32px; font-weight: 500; line-height: 1.1; margin-bottom: 10.5px; margin-top: 21px;">
<span style="box-sizing: border-box;"><u><span style="color: #0b5394;">SSH Key Authentication</span></u></span></h2>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">First of all we are going to setup a <a href="http://www.hackthesec.co.in/search/label/SSH" target="_blank">SSH </a>key authentication between development server (on which we have already installed Hugo) and the product server on which we will be setting up the production site with <a href="http://www.hackthesec.co.in/search/label/git" target="_blank">Git Hooks</a>.</span></span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Let’s run the command below to check if there’s already a key pair placed or not.</span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;"><span style="line-height: 1.42857;">root@ubuntu</span>:~$ ls ~/.ssh/id_rsa</span></pre>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">If it shows no such file on directory, run the command below to generate a new ssh key.</span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;"><span style="line-height: 1.42857;">root@ubuntu</span>:~$ ssh-keygen</span></pre>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Choose the file where you wish to save the key other than the default location. Then use the command below to copy this key to your production server.</span></span></div>
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<span style="font-family: Georgia, Times New Roman, serif;"><span style="box-sizing: border-box;"></span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;"><span style="line-height: 1.42857;">root@ubuntu</span>:~$ ssh-copy-id ubuntu@production_server_ip </span></pre>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">After providing the right user credentials you will see the following output.</span></span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; color: #333333; font-family: proxima-nova, 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<code style="background-color: #f9f2f4; border-radius: 4px; box-sizing: border-box; color: #c7254e; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 16.2px; padding: 2px 4px;">Number of key(s) added: 1</code></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="font-family: Georgia, Times New Roman, serif;">Now try logging into the machine, with:<br style="box-sizing: border-box;" />“ssh ‘ubuntu@12.23.55.21′”<br style="box-sizing: border-box;" />and check to make sure that only the key(s) you wanted were added.</span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Let’s run the command on your production server from the development server.</span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;"><span style="line-height: 1.42857;">root@ubuntu</span>:~$ ssh ubuntu@162.253.55.241 hostname</span></pre>
<h2 style="background-color: #fdfdfd; box-sizing: border-box; font-family: proxima-nova, 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 32px; font-weight: 500; line-height: 1.1; margin-bottom: 10.5px; margin-top: 21px;">
<span style="box-sizing: border-box;"><u><span style="color: #0b5394;">Initial Git Repo Transfer</span></u></span></h2>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">In order to setup the ‘post-receive’ hook on the production server in the near future, we need to transfer an initial clone of our Hugo repository to the production server. To do this, first we will create a bare repository from our main Hugo repository in the ‘/tmp’ directory. Bare repository is a special ‘git’ repository with no working directory. So, to create this copy we will use the ‘git clone’ command using the ‘–enable’ option as shown.</span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;"><span style="line-height: 1.42857;">root@ubuntu</span>:~$ git clone --bare ~/hugo_web /tmp/hugo_web.git </span></pre>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Then copy this bare repo to the home directory of your Production server user using the command as shown below.</span></span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="font-family: Georgia, Times New Roman, serif;"><span style="box-sizing: border-box;"></span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;"><span style="line-height: 1.42857;">root@ubuntu</span>:~$ scp -r /tmp/hugo_web.git ubuntu@prod-server_ip:</span></pre>
<h2 style="background-color: #fdfdfd; box-sizing: border-box; font-family: proxima-nova, 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 32px; font-weight: 500; line-height: 1.1; margin-bottom: 10.5px; margin-top: 21px;">
<span style="box-sizing: border-box;"><u><span style="color: #0b5394;">Adding Git Remote For Production</span></u></span></h2>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Let’s add the git to the remote production server as a tracked remote repository using its bare repo. This will allow us to push new content to our production server easily.</span></span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Now change your directory to Hugo website and then run the command to give name to the remote as ‘prod’ and specify the connection information and location to the bare repository on the remote system.</span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;"><span style="line-height: 1.42857;">root@ubuntu</span>:~$ cd hugo_web/</span>
<span style="box-sizing: border-box;"><span style="line-height: 1.42857;">root@ubuntu</span>:~/hugo_web$ git remote add prod ubuntu@prod_server_ip:hugo_web.git</span></pre>
<h2 style="background-color: #fdfdfd; box-sizing: border-box; font-family: proxima-nova, 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 32px; font-weight: 500; line-height: 1.1; margin-bottom: 10.5px; margin-top: 21px;">
<span style="box-sizing: border-box;"><u><span style="color: #0b5394;">Setup Production Server</span></u></span></h2>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">So far we have successfully configured our development server, now we are going to setup our production server by following some steps to install a few basic packages. Hugo installation then will create ‘post-receive’ script to deploy new content pushed to our repository.</span></span></div>
<h2 style="background-color: #fdfdfd; box-sizing: border-box; font-family: proxima-nova, 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 32px; font-weight: 500; line-height: 1.1; margin-bottom: 10.5px; margin-top: 21px;">
<span style="box-sizing: border-box;"><u><span style="color: #0b5394;">Installing Packages on Production Server</span></u></span></h2>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">We need to install Git, Pygments and <a href="http://www.hackthesec.co.in/search/label/NGINX" target="_blank">Nginx </a>server packages on our production server. The ‘Git’ software will be used to receive pushes and to execute our deployment script. Then we need to install ‘Pygments’ for syntaxt highlighting and ‘<a href="http://www.hackthesec.co.in/search/label/NGINX" target="_blank">Nginx</a>’ as the web server that will make your contents available for the visitors.</span></span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Let’s run the following command to update your Ubuntu server with the latest updates and patches.</span></span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="font-family: Georgia, Times New Roman, serif;"><span style="box-sizing: border-box;"></span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;">$ sudo apt-get update</span></pre>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Then run this command to install ‘git’, ‘nginx’ and ‘python-pip’ packages.</span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;">$ sudo apt-get install git nginx python-pip</span></pre>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Press ‘Y’ key to proceed with the installation process. Once these packages are installed, execute the command below to install Pygments using ‘pip’ command.</span></span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="font-family: Georgia, Times New Roman, serif;"><span style="box-sizing: border-box;"></span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;">$ sudo pip install Pygments</span></pre>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEikePEYPcCnqtyBU90w7UQ-zWcg-uIt2V12_Qec-tr6jIuu9KYhl9HCEXk42agYx_Pq08yNwSvfW8CdSeTRol18QpytUBj6Fxj6rcZPyTkzgsAcCjkiVWpGhPojrvVA7JvTJLRsQsoc3Nlx/s1600/pip-installation_www.hackthesec.co.in.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEikePEYPcCnqtyBU90w7UQ-zWcg-uIt2V12_Qec-tr6jIuu9KYhl9HCEXk42agYx_Pq08yNwSvfW8CdSeTRol18QpytUBj6Fxj6rcZPyTkzgsAcCjkiVWpGhPojrvVA7JvTJLRsQsoc3Nlx/s1600/pip-installation_www.hackthesec.co.in.png" /></a></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">The pakages have been installed. Now we can test if we have setup the remote repository correctly on our pre-prod development machine using the following command in the Hugo project directory.</span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;"><span style="line-height: 1.42857;">root@ubuntu</span>:~/hugo_web$ git ls-remote prod</span></pre>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"></span></div>
<h2 style="background-color: #fdfdfd; box-sizing: border-box; font-family: proxima-nova, 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 32px; font-weight: 500; line-height: 1.1; margin-bottom: 10.5px; margin-top: 21px;">
<span style="box-sizing: border-box;"><span style="color: #0b5394;"><u>Installing Hugo on Production</u></span></span></h2>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Run the following command to download the latest hugo package and then install using ‘<b>dpkg</b>’ command as shown in the image.</span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;">$ wget https://github.com/spf13/hugo/releases/download/v0.15/hugo_0.15_amd64.deb</span>
<span style="box-sizing: border-box;">$ sudo dpkg -i hugo_0.15_amd64.deb</span></pre>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">For confirmation run the command below to check the version of your Hugo installation.</span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;">$ hugo version</span></pre>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Now clone Hugo themes directly from Github into your home directory by executing the command below.</span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;">$ git clone --recursive https://github.com/spf13/hugoThemes ~/themes</span></pre>
<h2 style="background-color: #fdfdfd; box-sizing: border-box; font-family: proxima-nova, 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 32px; font-weight: 500; line-height: 1.1; margin-bottom: 10.5px; margin-top: 21px;">
<span style="box-sizing: border-box;"><u><span style="color: #0b5394;">Nginx Configuration to Serve Production Files</span></u></span></h2>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Here we will be configuring the Nginx <a href="http://www.hackthesec.co.in/search/label/Linux-Server" target="_blank">web server</a> to serve the files produced during the deployment. To do so we will create a new directory in our user’s home and then configure the default configuration file of Nginx to make a few adjustments.</span></span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="font-family: Georgia, Times New Roman, serif;"><span style="box-sizing: border-box;"></span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;">$ mkdir ~/public_html</span>
<span style="box-sizing: border-box;">$ sudo vim /etc/nginx/sites-available/default</span></pre>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhV9SIKfpXV6bLg_JroksDY1_yuyspJjZZbF6IvGI3L-48kGc4DHAwBbWzYoGxTnPcXiFeuOJhWaaQjWg0VQaXWm0DPrsNRZHs3bKi2GGkI1wpNmlD-3d-ru7luYj0IDacnSzQKQhPZZwVR/s1600/hugo_configuration_www.hackthesec.co.in.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhV9SIKfpXV6bLg_JroksDY1_yuyspJjZZbF6IvGI3L-48kGc4DHAwBbWzYoGxTnPcXiFeuOJhWaaQjWg0VQaXWm0DPrsNRZHs3bKi2GGkI1wpNmlD-3d-ru7luYj0IDacnSzQKQhPZZwVR/s1600/hugo_configuration_www.hackthesec.co.in.png" /></a></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Make sure that you have changed the document root path and server name according to your server IP address or domain name.</span></span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Then restart Nginx services, so that the changes will be applied.</span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;">$ sudo service nginx restart</span></pre>
<h2 style="background-color: #fdfdfd; box-sizing: border-box; font-family: proxima-nova, 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 32px; font-weight: 500; line-height: 1.1; margin-bottom: 10.5px; margin-top: 21px;">
<span style="box-sizing: border-box;"><u><span style="color: #0b5394;">Creating Post-Receive Hook to Deploy Hugo Site</span></u></span></h2>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">In this step we will be ready to work on post-receive hook deployment scripts by creating a new file in the ‘hooks’ directory present in the bare directory of our production server.</span></span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Change your directory to the ‘hooks’ and create a new file and put the following contents in it as shown below.</span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;">$ cd hugo_web.git/hooks/
<span style="box-sizing: border-box;"><span style="line-height: 1.42857;">root@ubuntu</span>:~/hugo_web.git/hooks$ vim post-receive

GIT_REPO=$HOME/hugo_web.git
WORKING_DIRECTORY=$HOME/hugo_web-working
PUBLIC_WWW=$HOME/public_html
BACKUP_WWW=$HOME/backup_html
MY_DOMAIN=162.253.55.241

set -e

rm -rf $WORKING_DIRECTORY
rsync -aqz $PUBLIC_WWW/ $BACKUP_WWW
trap "echo 'An issue has been occurred.  Reverting to backup.'; rsync -aqz --del $BACKUP_WWW/ $PUBLIC_WWW; rm -rf $WORKING_DIRECTORY" EXIT

git clone $GIT_REPO $WORKING_DIRECTORY
rm -rf $PUBLIC_WWW/*
/usr/bin/hugo -s $WORKING_DIRECTORY -d $PUBLIC_WWW -b "http://${MY_DOMAIN}"
rm -rf $WORKING_DIRECTORY
trap – EXIT</code></span></span></pre>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">In this file, after indicating the bash script, we have setup the ‘git_repo’ to our bare repository. Then, mention the ‘Working_Directory’ to clone this bare repository, while the ‘<b>Public_www</b>’ variable and backup web folder will be kept accessible through the ‘<b>Backup_www</b>’ variable.</span></span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">One thing that you should keep in mind is to change ‘My_Domain’ parameter with your production server’s IP. In the second part of the script, use a bash command, ‘set -e’ to exit immediately in case of any error.</span></span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="font-family: Georgia, Times New Roman, serif;"><span style="box-sizing: border-box;"></span></span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">In the last part of our script we have used the ‘trap’ command, so that in case of deployment failure the trap command will restore our backup copy to the web document root directory.</span></span></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhW24K7bWVwmrWS4uW2gMlADMNQIiWuO4Ff3sRhzr8ekMChQf9kAh22eyeTybzzgMjvrFQO-IwnJmS9HaVOPcSnkBXbLvEFB5V6rwqPP5W3L8iECG_hm-v84PhSa6sjFudLTDUY6lLJ-8GO/s1600/Post-Receive-Hook-to-Deploy-Hugo-Site_www.hackthesec.co.in.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhW24K7bWVwmrWS4uW2gMlADMNQIiWuO4Ff3sRhzr8ekMChQf9kAh22eyeTybzzgMjvrFQO-IwnJmS9HaVOPcSnkBXbLvEFB5V6rwqPP5W3L8iECG_hm-v84PhSa6sjFudLTDUY6lLJ-8GO/s1600/Post-Receive-Hook-to-Deploy-Hugo-Site_www.hackthesec.co.in.png" /></a></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">After completing the file configuration, use below command to give it executable permissions.</span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;"><span style="line-height: 1.42857;">root@ubuntu</span>:~/hugo_web.git/hooks$ chmod +x post-receive</span></pre>
<h2 style="background-color: #fdfdfd; box-sizing: border-box; font-family: proxima-nova, 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 32px; font-weight: 500; line-height: 1.1; margin-bottom: 10.5px; margin-top: 21px;">
<span style="box-sizing: border-box;"><u><span style="color: #0b5394;">Testing Deployment System</span></u></span></h2>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">This is the last step to test our production deployment system after completing the configurations. To do so, simply execute the bash script that we created in the previous step.</span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;"><span style="line-height: 1.42857;">root@ubuntu</span>:~/hugo_web.git/hooks$ bash post-receive</span>

<code style="background-color: transparent; border-radius: 0px; box-sizing: border-box; color: inherit; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: inherit; padding: 0px; white-space: pre-wrap;">Cloning into '/home/ubuntu/hugo_web-working'...
done.
0 of 2 drafts rendered
0 future content
2 pages created
0 paginator pages created
0 tags created
0 categories created
in 17 ms</code></pre>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Now you can open your web browser by giving the IP or FQDN of your production server to see the same contents you have configured in your pre-prod server.</span></span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">If you wish to add some more content, go back to your development server and run the command below to add a new post.</span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;"><span style="line-height: 1.42857;">root@ubuntu</span>:~/hugo_web$ hugo new post/Testing-Deployment.md</span></pre>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="font-family: Georgia, Times New Roman, serif;">A new file will be opened in your default editor, so put some new contents and close the file after saving the changes. Then run the following commands to add the contents to git and commit the changes.</span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;">root@ubuntu:~/hugo_web$ git add .</span>
<span style="box-sizing: border-box;">root@ubuntu:~/hugo_web$ git commit -m 'Deployment test'</span></pre>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Now run the following command to deploy the new contents on the pre-prod to the production server.</span></span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="font-family: Georgia, Times New Roman, serif;"><span style="box-sizing: border-box;"></span></span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: 14px; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><span style="box-sizing: border-box;"><span style="line-height: 1.42857;">root@ubuntu</span>:~/hugo_web$ git push prod master</span></pre>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="box-sizing: border-box;"><span style="font-family: Georgia, Times New Roman, serif;">Now visit your production server’s IP address in your web browser. You will be glad to see your new content in your web browser.</span></span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<a href="http://www.hackthesec.co.in/" target="_blank">www.hackthesec.co.in</a><br /><a href="http://www.hackthesec.co.in/" target="_blank">Hackthesec</a></div>
</div>
</div>

How To Deploy a Hugo Site to Production with Git Hooks on Ubuntu 14.04

Deploy a Hugo Site to Production with Git Hooks on Ubuntu Hugo is an open source static site generator. Static site generators build a w...

How to protect your SSH server with Fail2Ban on Ubuntu

<div dir="ltr" style="text-align: left;" trbidi="on">
<h1 class="entry-title" itemprop="headline" style="background-color: #fdfdfd; box-sizing: border-box; font-family: proxima-nova, 'Helvetica Neue', Helvetica, Arial, sans-serif; font-weight: 500; line-height: 1.1; margin: 21px 0px 0px;">
<span style="color: red; font-size: x-large;"><u><i>Protect your SSH server with Fail2Ban on Ubuntu</i></u></span></h1>
<div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="font-family: Georgia, Times New Roman, serif;">The most suitable application for this purpose is <a href="http://www.hackthesec.co.in/search/label/fail2ban" target="_blank">Fail2ban</a>. It is an intrusion prevention framework written in the Python programming language. It is able to run on servers that have an interface to a packet-control system or firewall installed locally. </span></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg_4cJIHMGOWul32IjKw2UHT3plp2cfuBxHMY7xFOQn3stZVpLEMarRug4jdQoFnKOtnQlH0Kr_lploQv_re2tP7msBLfE9WnJY18x5OiRKH12pqZMMiA_R0LCFsuAnMTxPffsoA6WjiHso/s1600/fail2ban_www.hackthesec.co.in.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg_4cJIHMGOWul32IjKw2UHT3plp2cfuBxHMY7xFOQn3stZVpLEMarRug4jdQoFnKOtnQlH0Kr_lploQv_re2tP7msBLfE9WnJY18x5OiRKH12pqZMMiA_R0LCFsuAnMTxPffsoA6WjiHso/s1600/fail2ban_www.hackthesec.co.in.jpg" /></a></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="font-family: Georgia, Times New Roman, serif;"><br /></span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="font-family: Georgia, Times New Roman, serif;">It scans log files and bans IPs that show the malicious signs — too many password failures, seeking for exploits, etc. In order to install <a href="http://www.hackthesec.co.in/search/label/fail2ban" target="_blank">fail2ban</a>, make sure your repositories are up to date and simply install it:</span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<strong style="background-color: white; color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.2px;"><span style="color: #0e0e0e; font-family: Open Sans, serif, sans-serif;"><span style="display: block; font-size: 18px; line-height: 1.4em; max-height: 200px;"></span></span></strong></div>
<ul style="text-align: left;">
<li><strong style="background-color: white; color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.2px;"><span style="color: #0e0e0e; font-family: Open Sans, serif, sans-serif;"><strong style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.2px;"><span style="color: #0e0e0e; font-family: Open Sans, serif, sans-serif;"><span style="font-size: 18px; line-height: 1.4em; max-height: 200px;"><a href="http://www.hackthesec.co.in/2016/01/how-to-protect-sshftp-using-fail2ban-on.html" target="_blank">How To Protect SSH/FTP using Fail2ban on CentOS/RHEL</a></span></span></strong></span></strong></li>
</ul>
<br />
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><code style="background-color: transparent; border-radius: 0px; box-sizing: border-box; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; padding: 0px; white-space: pre-wrap;"><span style="font-size: large;"># apt-get update
# apt-get install fail2ban</span></code><code style="background-color: transparent; border-radius: 0px; box-sizing: border-box; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: inherit; padding: 0px; white-space: pre-wrap;">
</code></pre>
<div style="background-color: #fdfdfd; box-sizing: border-box; font-size: 18px; line-height: 28px; margin-bottom: 10.5px;">
<span style="font-family: Georgia, Times New Roman, serif;">Once it is installed, it puts sample configuration file in <code style="background-color: #f9f2f4; border-radius: 4px; box-sizing: border-box; font-size: 16.2px; padding: 2px 4px;"><b>/etc/fail2ban/jail.conf</b></code>. We should copy the sample configuration file in <code style="background-color: #f9f2f4; border-radius: 4px; box-sizing: border-box; font-size: 16.2px; padding: 2px 4px;"><b>/etc/fail2ban/jail.local</b></code> and then, open file for editing using our favorite text editor. A lot of the possible services that we need to protect are already inside the sample file in their own section and there is DEFAULT section in the configuration file. Some of the important settings in this file are:</span></div>
<div style="background-color: #fdfdfd; box-sizing: border-box; margin-bottom: 10.5px;">
</div>
<ul style="text-align: left;">
<li><span style="font-family: Georgia, 'Times New Roman', serif; font-size: 18px; line-height: 28px;"><b>ignoreip</b>: We can use single IP, mask or a host name. IP addresses listed here will be excluded and will always be allowed to access the server</span></li>
<li><span style="font-family: Georgia, 'Times New Roman', serif; font-size: 18px; line-height: 28px;"><b>bantime</b>: The time (in seconds) that a host would be blocked from the server if they are found to be in violation of any of the defined rules. The default is set for 600 (10 minutes) but it should be increased to at least 30 minutes or more.</span></li>
<li><span style="font-family: Georgia, 'Times New Roman', serif; font-size: 18px; line-height: 28px;"><b>maxrwtry</b>: This is the number of incorrect login attempts allowed for a client before they get restricted to access the server. The default is 3.</span></li>
<li><span style="font-family: Georgia, 'Times New Roman', serif; font-size: 18px; line-height: 28px;"><b>backend</b>: specifies the backend used to get files modification. It should be set to “auto”</span></li>
<li><span style="font-family: Georgia, 'Times New Roman', serif; font-size: 18px; line-height: 28px;"><b>destemail</b>: We can specify email address where we want to get notifications when IP address is banned.</span></li>
</ul>
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<span style="font-family: Georgia, Times New Roman, serif;">Another important section is the ACTION section. Important lines here line describe that fail2ban will use the system iptables in order to ban suspicious IP address and specify the protocol that fail2ban will monitor which can be TCP or UDP.</span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><code style="background-color: transparent; border-radius: 0px; box-sizing: border-box; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; padding: 0px; white-space: pre-wrap;"><span style="font-size: large;">banaction = iptables-multiport
protocol = tcp</span></code><code style="background-color: transparent; border-radius: 0px; box-sizing: border-box; color: inherit; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: inherit; padding: 0px; white-space: pre-wrap;">
</code></pre>
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<span style="font-family: Georgia, Times New Roman, serif;">After we are done with the default settings and actions, we should setup our <a href="http://www.hackthesec.co.in/search/label/SSH" target="_blank">SSH </a>section which will make sure that the SSH access to our server is secured. Here is how the <a href="http://www.hackthesec.co.in/search/label/SSH" target="_blank">SSH </a>section should look inside the configuration file:</span></div>
<pre style="background-color: whitesmoke; border-radius: 4px; border: 1px solid rgb(204, 204, 204); box-sizing: border-box; color: #333333; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; line-height: 1.42857; margin-bottom: 10.5px; overflow: auto; padding: 10px; word-break: break-all; word-wrap: break-word;"><code style="background-color: transparent; border-radius: 0px; box-sizing: border-box; color: inherit; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; padding: 0px; white-space: pre-wrap;"><span style="font-size: large;">[ssh]

enabled  = true
port     = ssh
filter   = sshd
logpath  = /var/log/auth.log
maxretry = 4</span></code><code style="background-color: transparent; border-radius: 0px; box-sizing: border-box; color: inherit; font-family: Menlo, Monaco, Consolas, 'Courier New', monospace; font-size: inherit; padding: 0px; white-space: pre-wrap;">
</code></pre>
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<span style="font-family: Georgia, Times New Roman, serif;">This section makes <a href="http://www.hackthesec.co.in/search/label/SSH_Security" target="_blank">SSH monitoring active</a>, it listens on the SSH port for the ssh dameon, using the log file location <code style="background-color: #f9f2f4; border-radius: 4px; box-sizing: border-box; font-size: 16.2px; padding: 2px 4px;"><b>/var/log/auth.log</b></code> and bans the IP address of the user that will have 4 failed login attempts.</span></div>
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<span style="font-family: Georgia, Times New Roman, serif;">After all settings are made, we need to restart fail2ban and it will start monitoring the log files according to our settings, you can also check which rules are currently applied with the following <b><code style="background-color: #f9f2f4; border-radius: 4px; box-sizing: border-box; font-size: 16.2px; padding: 2px 4px;">iptables</code> </b>command.</span></div>
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<span style="font-family: Georgia, Times New Roman, serif;">Fail2ban is one of the most widely used applications when it comes to server security. It is very simple and effective, so you shouldn’t think twice in order to decide to install it on your server. It is a must have application.</span></div>
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<span style="font-family: Georgia, Times New Roman, serif;"><a href="http://www.hackthesec.co.in/">www.hackthesec.co.in</a></span></div>
</div>
</div>

How to protect your SSH server with Fail2Ban on Ubuntu

Protect your SSH server with Fail2Ban on Ubuntu The most suitable application for this purpose is Fail2ban . It is an intrusion prevent...

How to Hide Application Port Using knockd in Linux

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<span style="color: red; font-size: large;"><u><span style="font-family: "arial" , "helvetica" , sans-serif;"><span style="letter-spacing: -1px; line-height: 1.2em;">Hide </span><span style="letter-spacing: -1px; line-height: 38.4px;">Application</span><span style="letter-spacing: -1px; line-height: 1.2em;"> Port Using knockd in Linux</span></span></u></span></h1>
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As a system administrator, we should do everything to secure our server from attackers. As the internet grows, threats to our server is also growing. One of the popular entrances to attack our server is through the port on your server that open. If your SSH server is running on </div>
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your machine, then usually the SSH port is listening. Which means it is open, waiting for the connection.<br />
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Leaving the port open for 24 hours, is not recommended because it is vulnerable. Because we can scan the machine to see the open port. <strong>Nmap</strong> is one of the most popular port scanner that can be used by anyone to scan your machine.</div>
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How if we can open the on demand and close the port when it’s not used? Sounds interesting. Now we can do it using knockd application.</div>
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<span style="color: #0b5394;"><u>What is knockd</u></span></h1>
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Knockd is a port-knock server. It listens to all traffice on an ethernet (or PPP) interface, looking for special “knock” sequences of port-hits. (Source : <a href="http://www.zeroflux.org/projects/knock" style="outline: none; text-decoration: none;" title="knockd">http://www.zeroflux.org/projects/knock</a>)</div>
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<u><span style="color: #0b5394;">How it works</span></u></h1>
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Every application needs a port as a “door” for “listening” requests from other clients. This port usually on open state or close state. There are a lot of ports that available on the server. But there are some ports that agreed by consensus, such as <a href="http://www.hackthesec.co.in/search/label/SSH" target="_blank">SSH </a>(22), Web (80) and <a href="http://www.hackthesec.co.in/search/label/ftp" target="_blank">FTP </a>(21).</div>
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A basic rule of server security is to open only used ports and close the rest. You may have some ports that are sometimes used and sometimes not. Leaving those ports open while is not being used is not recommended.</div>
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When you install knockd, you can let the client “knock” the server with pattern. The knocking sequence can be custom by you. So this knocking pattern will be unique to each other. If the pattern is match, then the port you need will be opened for a period of time and the request can enter your server.</div>
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Once you have done with the application, you can close the port manually or automatically.</div>
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<span style="color: #0b5394;"><u>How to install knockd</u></span></h1>
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On this article, we are using Zorin 9 OS which based on Ubuntu 14.04 LTS. If you are using another distribution please adjust it to the installation method of your distribution.</div>
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Knockd is available on Ubuntu repository. Then we can use <b>apt-get to install knockd</b>.</div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-size: small;"><span style="font-size: large; line-height: 15.6px;"><span style="color: white;">$ sudo </span><span style="color: lime;">apt-get</span><span style="color: white;"> install </span><span style="color: lime;">knockd</span></span></span></pre>
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Just wait for a few minutes, then your knockd is already setup.</div>
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<span style="color: #0b5394;"><u>Configure knockd</u></span></h1>
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Knock configuration file is located in <strong>/etc/knockd.conf</strong><br />
The sample configuration is simple and easy to understand.</div>
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We can see that the configuration is divided into three sections. The <strong>[options]</strong> section, <strong>[openSSH]</strong> section to open SSH port and <strong>[closeSSH]</strong> section to close SSH port.</div>
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By default <strong>[options]</strong> section contain only 1 row. It tell us that the knockd log will be recorded using the operating system log application. On Ubuntu, we will see the log in <strong>/var/log/syslog</strong>; folder.</div>
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Of course we can choose not to use SysLog. We can change it into this line, if we want to use custom log.</div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-size: small;"><span style="font-size: large; line-height: 15.6px;"><span style="color: white;">logfile = /var/log/</span><span style="color: lime;">knockd.log</span></span></span></pre>
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The above line, will put knock log file in <strong>/var/log/knockd.log</strong></div>
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[openSSH] sections has identical commands with [closeSSH] section.</div>
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<strong>sequence = 1200,1300,1400</strong><br />
This is the knock pattern. It will trigger the command below in the section. The value of this parameter is fully customized. We can choose another random number.</div>
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<strong>seq_timeout = 10</strong><br />
This will tell knockd about how long the knock pattern must be completed in.</div>
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<strong>command = /sbin/iptables -I INPUT -s %IP% -p tcp --dport 22 -j ACCEPT</strong><br />
This parameter will open SSH port on port 22</div>
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<strong>tcpflags = syn</strong><br />
This parameter indicates that the Client will sends a TCP SYNchronize packet to the server</div>
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<span style="color: #0b5394;"><u>Setting up the firewall</u></span></h1>
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As we know before, knockd will open particular port temporarily. So we have to make sure firewall is running on the server. Basically, we will close all ports. We are using iptables syntax to do it. Here are the steps.</div>
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The 1st command, will allow the current on-going session through firewall.<br />
The 2nd command, will allow the server is able to ping by another machine.<br />
The 3rd command, will reject every requests.</div>
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To test the knockd service, we expect that our will firewall will drop all ssh connection. Then knockd will open it temporarily on demand.</div>
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<span style="color: #0b5394;"><u>Test the knockd on server side</u></span></h1>
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Once the firewall and knockd are setup, next we can test them.<br />
To test the firewall, try remote the server via SSH from another machine. (<em>on this article, client IP is 10.1.6.14 and server IP 10.0.76.224</em>)</div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-size: small;"><span style="font-size: large; line-height: 15.6px;"><span style="color: white;">$ ssh -l </span><span style="color: lime;">pungki </span><span style="color: white;">10.0.76.224</span></span></span></pre>
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With :<br />
<div style="font-size: 14px;">
<strong>-l</strong> = login name</div>
<div style="font-size: 14px;">
<strong>pungki</strong> = the user name on the destination server</div>
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If the firewall works, then we will get <strong>“Connection refused”</strong> error message.</div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjfRafJqFuFGUE3uaD6U5pfEqKmV8CwgJAc_b6-XdxHSaAoThuavWut-Q8G8Tm590Evw3g9mQkxHS9Zer5iE6Mme7HRMnyKw9fLpuObT6APc5xAgHKO44mQERwZwVKov6nZ-9RU0t_BL04u/s1600/connection_refused_www.hackthesec.co.in.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjfRafJqFuFGUE3uaD6U5pfEqKmV8CwgJAc_b6-XdxHSaAoThuavWut-Q8G8Tm590Evw3g9mQkxHS9Zer5iE6Mme7HRMnyKw9fLpuObT6APc5xAgHKO44mQERwZwVKov6nZ-9RU0t_BL04u/s1600/connection_refused_www.hackthesec.co.in.png" /></a></div>
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The reason we get the error message is the 10.1.6.14 is not allowed to enter the server. If we use this command, we will see no result.</div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-size: small;"><span style="font-size: large; line-height: 15.6px;"><span style="color: white;">$ </span><span style="color: lime;">sudo /sbin/iptables -L</span><span style="color: white;"> -n |grep 10.1.6.14</span></span></span></pre>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhlW_3AQMtYbLz_q36ogYB6i0YJjh4ge86K41UwVbalkoKmgBrhnHVhob46hi21H8dr7xaHH_b1G4gc3LK4fwoWEYVtbPg6LhccN3CDsm2CxXbxQJT3HCRSYXNN36U9COiy7LuHd9-2wmmC/s1600/iptables_before_knock_www.hackthesec.co.in.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhlW_3AQMtYbLz_q36ogYB6i0YJjh4ge86K41UwVbalkoKmgBrhnHVhob46hi21H8dr7xaHH_b1G4gc3LK4fwoWEYVtbPg6LhccN3CDsm2CxXbxQJT3HCRSYXNN36U9COiy7LuHd9-2wmmC/s1600/iptables_before_knock_www.hackthesec.co.in.png" /></a></div>
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Later, we will see the difference after knockd implemented.</div>
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Next step, is to test the knockd service.</div>
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To run knockd, we need to change knockd default file which located in /etc/default/knockd. Change the value of <strong>START_KNOCKD parameter from 0 to 1</strong>.</div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhaZe0IJykHyWEfqgWsgqhoIjObun1UVhtKQaU8RUIYT6aK8Bf6Y0TVRZgvWb1oYiLvL2oMsJq0UJYuFczFGTS83J7Z-zJqdSX5VvoRNYTCfkCNoOFfVhU5m7dTzPWSKiNZij9_HvXRUjhT/s1600/default_knockd_www.hackthesec.co.in.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhaZe0IJykHyWEfqgWsgqhoIjObun1UVhtKQaU8RUIYT6aK8Bf6Y0TVRZgvWb1oYiLvL2oMsJq0UJYuFczFGTS83J7Z-zJqdSX5VvoRNYTCfkCNoOFfVhU5m7dTzPWSKiNZij9_HvXRUjhT/s1600/default_knockd_www.hackthesec.co.in.png" /></a></div>
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Save the file. Then type :</div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-size: small;"><span style="font-size: large; line-height: 15.6px;"><span style="color: white;">$ sudo </span><span style="color: lime;">service knockd</span><span style="color: white;"> start</span></span></span></pre>
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*<em>note : I tried to run the service using /etc/init.d/knockd start , but it always fail to start</em></div>
<h1 style="background-color: white; font-family: Arial, Helvetica, sans-serif; font-size: 20pt; letter-spacing: -1px; line-height: 1.2em; margin: 0px 0px 15px; padding: 0px;">
<span style="color: #0b5394;"><u>Test knockd from Client side</u></span></h1>
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On the client side, we need knock client to “knock” the server. On the client side, we use Centos 5.2. Then we install knock-client from <a href="http://pkgs.repoforge.org/knock/knock-0.5.3.el5.rf.i386.rpm" style="outline: none; text-decoration: none;" title="knock client">http://pkgs.repoforge.org/knock/knock-0.5.3.el5.rf.i386.rpm</a></div>
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Then run the command below to knock the server :</div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-size: small;"><span style="font-size: large; line-height: 15.6px;">$ knock -v 10.0.76.224 1200 1300 1400</span></span></pre>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiT-KXni4C1INDyp91QdgH7yvG91kZqKOEcYMcWhZdz5fsUlTNUldddqAee8sHvviRBFJBgYewr2odXHyNyXjcTQ_5-bCUELvpd05hsNe0CItVvTYgegGHi5rhxYso1PmqIB7Mnxcn_nBYI/s1600/knock_open_www.hackthesec.co.in.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiT-KXni4C1INDyp91QdgH7yvG91kZqKOEcYMcWhZdz5fsUlTNUldddqAee8sHvviRBFJBgYewr2odXHyNyXjcTQ_5-bCUELvpd05hsNe0CItVvTYgegGHi5rhxYso1PmqIB7Mnxcn_nBYI/s1600/knock_open_www.hackthesec.co.in.png" /></a></div>
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<strong>-v</strong> = verbose<br />
<strong>10.0.76.224</strong> = Server IP<br />
<strong>1200 1300 1400</strong> = knock sequence which defined in the knockd configuration</div>
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After knock the server, now we will see that the client IP is now allowed to enter the server.</div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-size: small;"><span style="font-size: large; line-height: 15.6px;"><span style="color: white;">$ sudo /sbin/</span><span style="color: lime;">iptables </span><span style="color: white;">-L -n |grep 10.1.6.14</span></span></span></pre>
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Then we can run SSH to remote the server.</div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjINYEuu7LmyDs7fvdRsVd38bC5K8Z15OTpi7ZNei7wNDzoWW4jSmV9023OiY4aI0ZfDP5XMeFreENSehDFjnRlBCHQCJjj-hoa-5vx_Bk51mmIEIJYJMT5E9phhW3X_GL67zhkaYP9UPtZ/s1600/ssh_success_after_knock_1_www.hackthesec.co.in.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjINYEuu7LmyDs7fvdRsVd38bC5K8Z15OTpi7ZNei7wNDzoWW4jSmV9023OiY4aI0ZfDP5XMeFreENSehDFjnRlBCHQCJjj-hoa-5vx_Bk51mmIEIJYJMT5E9phhW3X_GL67zhkaYP9UPtZ/s1600/ssh_success_after_knock_1_www.hackthesec.co.in.png" /></a></div>
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As we can see on the above image, the host name of are different. After SSH to the remote machine established then the host name is changed from @web01 into @dev-machine.</div>
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<span style="color: #0b5394;"><u>Close the port</u></span></h1>
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After the client done to remote the server, the client need to close the port. To do that, we can use the command below :</div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-size: small;"><span style="font-size: large; line-height: 15.6px;"><span style="color: white;">$ </span><span style="color: lime;">knock </span><span style="color: white;">-v 10.0.76.224 1400 1300 1200</span></span></span></pre>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjseKC2KePBKaJufOpIsrsJfwjiU8L08ZMVOMFPEEGBsIcRr-pUpfbtcDurAkGDY-0XYN_hGxf1JUPlAnPg7hF4wVCI7dG1q3-nnq6sWwkUN_a8IKq3OG3nibdSX93H5a_QdfGOrQILERhP/s1600/knock_close_www.hackthesec.co.in.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjseKC2KePBKaJufOpIsrsJfwjiU8L08ZMVOMFPEEGBsIcRr-pUpfbtcDurAkGDY-0XYN_hGxf1JUPlAnPg7hF4wVCI7dG1q3-nnq6sWwkUN_a8IKq3OG3nibdSX93H5a_QdfGOrQILERhP/s1600/knock_close_www.hackthesec.co.in.png" /></a></div>
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<em><strong>Please be careful</strong>, to close the port, we put the knock sequence in the opposite order.</em></div>
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After knock the server, we will see a prompt again. To check if the knock was success, we use iptables command again. If it was success, we will see that IP 10.1.6.14 will disappeared.</div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg10Hwu4L6yAHomwQ2jSZ3ZCHYjJfWKC431IPW1b-qU2qyrUw3WGasrdHXFk5gvu0rfzXlobAOaA63L9_blX2lc6Dv3dztXyMRuquceOPguOa_G2UD32-rEM-a-Ltt8hKUU8oQZ7BXBB8l-/s1600/iptables_after_knock_closed_www.hackthesec.co.in.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg10Hwu4L6yAHomwQ2jSZ3ZCHYjJfWKC431IPW1b-qU2qyrUw3WGasrdHXFk5gvu0rfzXlobAOaA63L9_blX2lc6Dv3dztXyMRuquceOPguOa_G2UD32-rEM-a-Ltt8hKUU8oQZ7BXBB8l-/s1600/iptables_after_knock_closed_www.hackthesec.co.in.png" /></a></div>
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On the previous one, after knock to open the port, we saw that the client IP Address - 10.1.6.14 - is allowed to enter the server by firewall. Now, after we knock to close the port, if we check with the same iptables command, the rule was deleted.</div>
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<span style="color: #0b5394;"><u>Close the port Automatically</u></span></h1>
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Since the close port activity is triggered by client, we will have the possibility that the client forget to close the port. We don’t want it to happen. So we can configure knockd to close the port automatically.</div>
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In order to do that, <strong>we need to customize</strong> the knockd configuration file. Here is the sample of modified knockd configuration file.</div>
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The command still looks identical. The difference with the previous configuration is we put [openSSH] section and [closeSSH] section in the same block.</div>
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Then we add <strong>cmd_timeout = 10</strong> line to tell the server <strong>to execute the stop_command 10 seconds after start_command is executed</strong>. The port will be automatically closed, but the established connection remain connected.</div>
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How to Hide Application Port Using knockd in Linux

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