Note:  There is also an Enterprise level version of DogTag known as the Red Hat Certificate System.

Before we go any further, I need to send a huge call-out to Vivek Santuka who prototyped & pioneered this initiative at work.  Also a call-out to Brian Sak for updating the work that Vivek did.

Note:  It is assumed that you are logged in as “root” to perform the activities in this document.  If not, use the “su –“ command to change your login context to the superuser (root).

[root@atw-dogtag01 ~]# vi /etc/sysconfig/network-scripts/ifcfg-eth0

[root@atw-dogtag01 ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth0

DEVICE=”eth0″

HWADDR=”00:50:56:B8:BC:08″

ONBOOT=”yes”

NM_CONTROLLED=”yes”

BOOTPROTO=none

IPADDR=10.1.100.229

NETMASK=255.255.255.0

USERCTL=yes

TYPE=Ethernet

DNS1=10.1.100.103

GATEWAY=10.1.100.1

[root@atw-dogtag01 ~]# chkconfig network on

[root@atw-dogtag01 ~]# service network restart

Install Packages with yum

Fedora uses a software package manager called “yum” to manage the installed packages within the operating system.  yum provides the advantage of identifying dependencies and helping to manage the installation of the application and all of that applications dependencies.  See http://fedoraproject.org/wiki/Yum for more on yum.

We will use yum to update this Fedora 15 server to the latest packages, as well as install needed applications such as NTP.

Configure Proxy (if needed)

The setup used to write this document required a proxy server to access the Internet.  Therefore this procedure was included.  If your environment does not require a proxy to access the Internet, please go to Procedure 2.

Step 1 Use your favorite text editor to edit the yum configuration file located at /etc/yum.conf

Example 4 – Editing the yum configuration file

Step 2 Add a line for with a field of “proxy=” followed by the URL and Port for your proxy server

Example 5 – Complete yum.conf file

Update system with yum

Step 1 Add a yum plugin to choose the fastest location to download from.  This plugin saved hours during the writing of this paper.

Example 6 – Installing the fastest mirror plugin

 

Step 2 Update all installed packages with the “yum update” command

Example 7 – Updating all installed packages with yum

Install and Configure the NTP Service

Certificates require strict time synchronization.  It’s recommended to use the network time protocol (NTP) to ensure the time is accurate on the Certificate Authority.  The NTP service (aka: NTP daemon) is not installed by default with the minimal installation of Fedora 15, so we will use yum to install it.

1. Install the NTP Service with the “yum install ntp” command
2. Use the “chkconfig ntpd on” command to ensure ntp daemon starts at boot
3. Use the ntpdate ntp_server_ip_address command to sync to an NTP source
4. Ensure the service is started with the “ntpd start” command

Example 8 – Installing, syncing and starting NTP

[root@atw-dogtag01 ~]# yum install ntp

[root@atw-dogtag01 ~]# chkconfig ntpd on

[root@atw-dogtag01 ~]# ntpdate 172.25.73.1

31 Jul 13:47:44 ntpdate[11361]: step time server 172.25.73.1 offset 64.503042 sec

[root@atw-dogtag01 ~]# /etc/init.d/ntpd start

Starting ntpd (via systemctl):                             [  OK  ]

[root@atw-dogtag01 ~]#

 

Install the LDAP server

Dog Tag uses an open source LDAP server called “Directory Server” to store its data.  Before you can install Dog Tag, Directory Server must be installed and prepared. 

Step 1 Install the LDAP server package with the “yum install 389-ds” command

Step 2 Create a new user named “ds389” to be used by the Directory Server

Example 9 – Installing Directory Server and creating the service account

 

Step 3 Launch the Directory Server configuration wizard using the setup-ds.pl script located in /usr/sbing/setup-ds.pl

Example 10 – Launching the setup script

Step 4 Accept the defaults.  Once you reach the portion where the wizard is asking for a System User, you will need to change the default (nobody) to the ds389 user.  Use the ds389 for the group as well, as seen in Example – 11

Example 11 – Setting the System User and Group to ds389

Step 5 Set the password for the Directory Manager

Example 12 – Setting the Directory Manager password and successs message

Install the PHP services

Step 1 Use yum to install php as seen in example 13

Example 13 – installing php with yum

Step 2 Start the apache (httpd) and Directory Server (dirsrv) services and configure them to start on bootup as seen in example 4

Example 14 – Starting the apache and directory server services

Install DogTag

Step 1 Install DogTag with the yum install pki-ca command as seen in Example 15

Example 15 – installing DogTag

Modify the Firewall Rules (IPTables)

In order to connect to the DogTag service on the ports used in procedure 3, you must modify the Linux server’s host-firewall (iptables) to allow the connections.  Since this is not an iptables document, and in order to keep this simple, let’s just turn off iptables.

Step 1 Stop the firewall service with the “service iptables stop” command

Step 2 Keep the firewall from starting when the server is booted with the “chkconfig iptables off” command.

Example 16 – Shutting off the Firewall

Create a new CA Instance

Now that DogDag is installed, you need to create a new Certificate Authority instance. The following is using ports that we have preferred to use.  You may change any of the parameters in the following section to suite the needs of your organization.

Step 1 Create a pki instance using the pkicreate command with the following options:

·       pki_instance_root=/var/lib

#This is setting the root location to store the pki instance.  Based on the settings used in example 17, it will be placed in the following directory: /var/lib/ise-ca.

·       pki_instance_name=ise-ca 

#This is naming the new CA instance “ise-ca”.  you may replace this with another name, to suit the needs of your organization.

·       subsystem_type=ca 

#Sets the subsystem to be a certificate authority.  Other possible sub-systems are not applicable to this guide.

·       agent_secure_port=9443 

# Agent Services are where an administrator can see what certificate has been provisioned, revoke them, etc.

·       ee_secure_port=9444 

# Sets the SSL port for End-Entities web services. 

·       ee_secure_client_auth_port=9446  

# Sets the SSL port for End-Entities authentication.

·       admin_secure_port=9447 

# This is the default port to use to access the CA Services Page as the administrator.

·       unsecure_port=9180 

# Sets the regular port number. When not specified, it will be randomly generated.

·       tomcat_server_port=9701  #

·       user=pkiuser  #

·       group=pkiuser  #

·       redirect conf=/etc/ise-ca  

# configures the configuration data to be stored in /etc/ise-ca

·       redirect logs=/var/log/ise-ca 

# configures the logs to be in the /var/log/ise-ca directory.

·       verbose 

# sets the install to be in verbose mode, to provide you with as much detail as possible.

Example 17 – Creating the pki instance

Step 2  Proceed with the Graphical Configuration of the DogTag CA

Once the setup script complete running, a message will be displayed with a unique URL to access the DogTag GUI and complete the CA installation, as seen in example 18.

Example 18 – Example of Unique URL to DogTag GUI

Step 3 Click Next from the Welcome Screen

Step 4 Create a “New Security Domain”.  Name it “ISE BYOD Domain” & click Next

Step 5 Name the Subsystem “Certificate Authority” & click Next

Step 6 Make this a Self-Signed Root CA within this new PKI Hierarchy.  Of course this could become a subordinate CA of an existing CA.  However, that is not the focus of this post.

Step 7 The Internal Database is the Directory Server (ds389) that we installed earlier.  All settings should be filled in correctly.  Please add the Directory Manager password created earlier in Example 12.

Step 8 Generate the Keypairs.  The default of RSA w/ SHA256 and a key size of 2048 bits will work fine, then click next.

Step 9 The certificate subject lines can be left at their default values, and click next

Step 10 If there are actions needed, they will be in red.  If not, click Next

Step 11 Provide a password, and export the CA’s key pair.  Store the key pair in a secure location.

Step 12 The new root CA certificate will be imported into your browser or your local certificate store, to ensure your system trusts certificates signed by this new CA.

Step 13  You should now be asked to install an Administrative Certification.  This is a personal certificate to identify you (the admin) to the CA for administrative tasks.  Please ensure you backup and store this key in a secure location, as you will not be able to administer the CA without this identity certificate.

You are finished with the GUI-Based configuration.

Note:  while the GUI Configuration is complete, we are not ready to begin using the CA just yet.  We still need to add a custom script and modify some more configuration files.

Enable and Configure SCEP

Here you will be enabling and configuring Simple Certificate Enrollment Protocol (SCEP) by directly modifying the CS.cfg file.

Step 1 Backup the CS.cfg file before making any changes.

 Example 20 – Backup of the CS.cfg file

Step 2 Open up the CS.cfg file in a text editor.

Example 21 – Edit the CS.cfg file

Step 3 Add the following lines to the bottom of the CS.cfg file and save the changes.

ca.scep.allowedEncryptionAlgorithms=DES3

ca.scep.allowedHashAlgorithms=SHA1,SHA256,SHA512

ca.scep.enable=true

ca.scep.encryptionAlgorithm=DES3

ca.scep.hashAlgorithm=SHA256

ca.scep.nonceSizeLimit=16

Step 4 Backup the caRouterCert.cfg file before making any changes.

Example 22 – Backing up the caRouterCert.cfg file

Step 5 Edit the caRouterCert.cfg file using a text editor.  Delete the value for the variable auth.instance_id and save your changes.  The end result should look like Example 24.

Example 23 – Edit the caRouterCert.cfg file

Example 24 – The final setting for auth.instance_id= field in the caRouterCert.cfg file

Step 6 Restart the CA services with the “service pki-cad restart“command

Example 25 – Restart the CA Services

Prepare Apache

Step 1 Move the Apache Welcome.conf file to disable the default installation

Example 26 – Move the welcome.conf file

Step 2 Create a new file called scepproxy.php at /var/www/html.

Example 27 – Creating the scepproxy.php file

Step 3 Populate the file with the following PHP script and save the file when completed.

 

Step 4 Restart the Apache service to reflect your changes with the “service httpd restart” command

The DogTag installation is complete.  You are ready to add this CA to ISE for BYOD certificate provisioning.

Configure ISE to use the new DogTag CA

This document is assuming your already have your BYOD policies ready, or you will create them afterwards.  In this section, we will focus on the simple task of adding the new DogTag CA to ISE for purposes of SCEP provisioning the BYOD certificates.

For more on configuring ISE for BYOD, please see the BYOD How-To Guides here:  http://www.cisco.com/en/US/solutions/ns340/ns414/ns742/ns744/landing_DesignZone_TrustSec.html

Add DogTag to the SCEP RA Profiles

From the ISE administrative GUI, we will add the DogTag server to the SCEP RA Profiles

Step 1 Navigate to Administration >> System >> Certificates >> SCEP RA Profiles & Click Add

Step 2 Name the RA “DogTag” & Enter a Description

Step 3 Enter the DogTag Server URL of http://<server_name>/scepproxy.php

Step 4 Click “Test Connectivity”

Click Submit.  You are finished & ready to onboard.

Thanks so much for taking the time to read my boring blog posts.  I hope they are useful.  Please feel free to send your comments.