If you're new to Shibboleth and need to implement it for web application authentication on Ubuntu Server 10.04 LTS, this guide will walk you through practical steps with concrete examples. Shibboleth is a powerful SAML-based SSO solution, but its learning curve can be steep without proper resources.

Before diving into implementation, here are key resources:

• Official Shibboleth 2 Documentation: https://spaces.internet2.edu/display/SHIB2/Installation
• Shibboleth Consortium Wiki: https://wiki.shibboleth.net
• Internet2 Middleware Initiative: https://www.internet2.edu/products-services/trust-identity-middleware/

Here's a step-by-step installation guide with commands:

# Add the Shibboleth repository
echo "deb http://pkg.shibboleth.net/ubuntu lucid main" | sudo tee /etc/apt/sources.list.d/shibboleth.list

# Import the GPG key
wget -qO - http://pkg.shibboleth.net/ubuntu/bionic/Release.key | sudo apt-key add -

# Update package lists
sudo apt-get update

# Install Shibboleth SP package
sudo apt-get install libapache2-mod-shib2

# Enable the module
sudo a2enmod shib2

After installation, configure your SP by editing /etc/shibboleth/shibboleth2.xml:

<ApplicationDefaults entityID="https://your-sp.example.org/shibboleth"
    REMOTE_USER="eppn persistent-id targeted-id">
    
    <Sessions lifetime="28800" timeout="3600" checkAddress="false"
        handlerSSL="true" cookieProps="https">
        
        <SSO entityID="https://your-idp.example.org/idp/shibboleth">
            SAML2 SAML1
        </SSO>
        
        <Logout>SAML2 Local</Logout>
    </Sessions>
    
    <MetadataProvider type="XML" file="idp-metadata.xml"/>
</ApplicationDefaults>

To protect a specific location in Apache:

<Location /secure>
    AuthType shibboleth
    ShibRequestSetting requireSession true
    Require valid-user
</Location>

Check these log files when debugging:

• /var/log/shibboleth/shibd.log - SP daemon logs
• /var/log/shibboleth/transaction.log - Detailed transaction logs
• /var/log/apache2/error.log - Apache error logs

For production environments, consider these security enhancements:

# In shibboleth2.xml
<Sessions ... handlerSSL="true" cookieProps="; SameSite=Strict; Secure">

# Enable strict metadata checking
<MetadataProvider ... validate="true">
    <MetadataFilter type="RequireValidUntil" maxValidityInterval="2419200"/>
    <MetadataFilter type="Signature" certificate="metadata-cert.pem"/>
</MetadataProvider>

Use these tools to verify your setup:

• Shibboleth SP test page: https://your-server/Shibboleth.sso/Status
• SAML tracer browser extension for debugging assertions
• curl commands to test protected endpoints

---

Shibboleth operates as a SAML-based SSO solution with two primary components: Identity Providers (IdP) and Service Providers (SP). For web application authentication, we'll focus on the SP implementation.

First, ensure your system meets requirements:

sudo apt-get update
sudo apt-get install apache2 libapache2-mod-shib2 opensaml2-tools

Edit the main configuration file:

sudo nano /etc/shibboleth/shibboleth2.xml

Key elements to configure:

<ApplicationDefaults entityID="https://yourdomain.example.org/shibboleth"
    REMOTE_USER="eppn persistent-id targeted-id">
    
<Sessions lifetime="28800" timeout="3600" checkAddress="false"
    handlerSSL="true" cookieProps="https">

Generate your SP metadata:

sudo shib-keygen -f
sudo shibd -t

Exchange metadata with your IdP. A typical metadata file looks like:

<md:EntityDescriptor xmlns:md="urn:oasis:names:tc:SAML:2.0:metadata"
    entityID="https://yourdomain.example.org/shibboleth">
    <md:SPSSODescriptor protocolSupportEnumeration="urn:oasis:names:tc:SAML:2.0:protocol">
        <md:AssertionConsumerService 
            Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST"
            Location="https://yourdomain.example.org/Shibboleth.sso/SAML2/POST"
            index="1"/>
    </md:SPSSODescriptor>
</md:EntityDescriptor>

Configure your virtual host:

<VirtualHost *:443>
    ServerName yourdomain.example.org
    SSLEngine on
    # Your SSL certificate configuration here
    
    <Location /secure>
        AuthType shibboleth
        ShibRequestSetting requireSession 1
        Require valid-user
    </Location>
</VirtualHost>

Create a simple test page to verify attributes:

<?php
require_once('/usr/share/shibboleth/ssp-modules.php');
$attrs = shib_attrs();
echo "<pre>";
print_r($attrs);
echo "</pre>";
?>

Check logs for errors:

tail -f /var/log/shibboleth/shibd.log
tail -f /var/log/apache2/error.log

Common problems include:

• Clock skew between SP and IdP
• Incorrect entityIDs in metadata
• Missing attribute mappings

For more complex scenarios, consider:

<RequestMapper type="XML">
    <RequestMap applicationId="default">
        <Host name="yourdomain.example.org" applicationId="yourApp"/>
    </RequestMap>
</RequestMapper>