strongSwan

h1. PT-TLS SWIMA Server

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h2. Installing the strongSwan TNC Software

First we have to install some additional Ubuntu packages needed for the strongSwan TNC build

<pre>

 sudo apt install libsystemd-dev libssl-dev libcurl4-openssl-dev sqlite3 libsqlite3-dev libjson0-dev

</pre>

Download the lastest strongSwan tarball

<pre>

wget https://download.strongswan.org/strongswan-5.6.0dr1.tar.bz2

</pre>

Unpack the tarball

<pre>

tar xf strongswan-5.6.0dr1.tar.bz2

</pre>

and change into the strongSwan build directory

<pre>

cd strongswan-5.6.0dr1

</pre>

Configure strongSwan with the following options

<pre>

./configure --prefix=/usr --sysconfdir=/etc --disable-gmp --enable-openssl --enable-tnc-imv --enable-tnc-pdp --enable-tnccs-20 --enable-imv-os --enable-imv-swima --enable-sqlite --enable-curl --disable-stroke --enable-swanctl --enable-systemd

</pre>

Build and install strongSwan with the commands

<pre>

make; sudo make install

</pre>

The following TNC server options have to be configured in */etc/strongswan.conf*

<pre>

charon-systemd {

  journal {

    default = 1

    tnc = 2

    imv = 3

    pts = 2

  }

  syslog {

    auth {

      default = 0

    }

  }

  plugins {

    tnccs-20 {

      max_batch_size = 131056

      max_message_size = 131024

    }

    tnc-pdp {

      server = tnc.example.org

      pt_tls {

        enable = yes

      }

      radius {

        enable = no

      }

    }

  }

}

libtls {

  suites = TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256

}

libimcv {

  database = sqlite:///etc/pts/config.db

  policy_script = ipsec imv_policy_manager

  plugins {

    imv-swima {

      rest_api {

        uri = https://admin-user:ietf99hackathon@tnc.example.com/api/

        timeout = 360

      }

    }

  }

}

</pre>

The */etc/tnc_config* file defines which Integrity Measurement Collectors (IMVs) are loaded by the TNC server

<pre>

#IMV-Configuration

IMV "OS"        /usr/lib/ipsec/imcvs/imv-os.so

IMV "SWIMA"     /usr/lib/ipsec/imcvs/imv-swima.so

</pre>

h2. Setting up a CA using the strongSwan "pki" Tool

The strongSwan *pki* tool is very powerful and easy to use. First we create a directory where all keys and certificates are going to be stored

<pre>

  sudo -s

  mkdir /etc/pts

  mkdir /etc/pts/pki

  cd /etc/pts/pki

</pre>

Then we generate an ECC public key pair for the Root CA and a matching self-signed CA certificate

<pre>

pki --gen --type ecdsa --size 256 --outform pem > caKey.pem

pki --self --ca --in caKey.pem --type ecdsa --dn "C=CZ, O=IETF, OU=SACM, CN=IETF 99 Prague Hackathon CA" --lifetime 3652 --outform pem > caCert.pem

</pre>

The CA certificate can be listed with the following command

<pre>

pki --print --in caCert.pem

  subject:  "C=CZ, O=IETF, OU=SACM, CN=IETF 99 Prague Hackathon CA"

  issuer:   "C=CZ, O=IETF, OU=SACM, CN=IETF 99 Prague Hackathon CA"

  validity:  not before Jul 07 08:19:08 2017, ok

             not after  Jul 07 08:19:08 2027, ok (expires in 3651 days)

  serial:    3a:98:52:2e:75:a5:a5:8b

  flags:     CA CRLSign self-signed

  subjkeyId: 81:44:64:84:26:5f:f6:08:80:4a:c9:77:32:0e:b2:78:d0:8f:e5:84

  pubkey:    ECDSA 256 bits

  keyid:     85:94:42:42:d7:40:83:17:98:72:7f:d7:6b:4a:08:51:e8:5b:e0:63

  subjkey:   81:44:64:84:26:5f:f6:08:80:4a:c9:77:32:0e:b2:78:d0:8f:e5:84

</pre>

<pre>

pki --req --in serverKey.pem --type ecdsa --dn "C=CZ, O=IETF, OU=SACM, CN=TNC Server" --san "tnc.example.com" --outform pem > serverReq.pem

</pre>

<pre>

pki --issue --cakey caKey.pem --cacert caCert.pem --in serverReq.pem --type pkcs10 --flag serverAuth --lifetime 1461 --outform pem > serverCert.pem

</pre>

<pre>

pki --print --in serverCert.pem

  subject:  "C=CZ, O=IETF, OU=SACM, CN=TNC Server"

  issuer:   "C=CZ, O=IETF, OU=SACM, CN=IETF 99 Prague Hackathon CA"

  validity:  not before Jul 07 09:07:31 2017, ok

             not after  Jul 07 09:07:31 2021, ok (expires in 1460 days)

  serial:    40:53:6a:88:f5:52:50:3b

  altNames:  tnc.example.com

  flags:     serverAuth

  authkeyId: 81:44:64:84:26:5f:f6:08:80:4a:c9:77:32:0e:b2:78:d0:8f:e5:84

  subjkeyId: 9c:83:b7:e9:0a:7d:dd:08:1f:2d:c5:c6:cc:63:c0:3f:96:57:a2:ce

  pubkey:    ECDSA 256 bits

  keyid:     15:91:40:5f:55:58:1f:9c:18:c1:89:6d:47:7c:bd:50:3d:b4:90:a1

  subjkey:   9c:83:b7:e9:0a:7d:dd:08:1f:2d:c5:c6:cc:63:c0:3f:96:57:a2:ce

</pre>

The server key and the server and CA certificates are needed by the strongSwan TNC server and are therefore copied to the default locations.

<pre>

cp caCert.pem /etc/swanctl/x509ca

cp serverCert.pem /etc/swanctl/x509

cp serverKey.pem /etc/swanctl/ecdsa

</pre>

Right after installation the strongSwan TNC daemon has to be enabled and started as a systemd service with the following commands

<pre>

sudo systemctl enable strongswan-swanctl

sudo systemctl start strongswan-swanctl

</pre>

In all subsequent reboots the *strongswan-swanctl* service will be started automatically. The following *swanctl* command shows that the service is running and that the certificates and keys have been loaded

<pre>

 swanctl --list-certs

List of X.509 End Entity Certificates

  subject:  "C=CZ, O=IETF, OU=SACM, CN=TNC Server"

  issuer:   "C=CZ, O=IETF, OU=SACM, CN=IETF 99 Prague Hackathon CA"

  validity:  not before Jul 07 09:07:31 2017, ok

             not after  Jul 07 09:07:31 2021, ok (expires in 1460 days)

  serial:    40:53:6a:88:f5:52:50:3b

  altNames:  tnc.example.com

  flags:     serverAuth

  authkeyId: 81:44:64:84:26:5f:f6:08:80:4a:c9:77:32:0e:b2:78:d0:8f:e5:84

  subjkeyId: 9c:83:b7:e9:0a:7d:dd:08:1f:2d:c5:c6:cc:63:c0:3f:96:57:a2:ce

  pubkey:    ECDSA 256 bits, has private key

  keyid:     15:91:40:5f:55:58:1f:9c:18:c1:89:6d:47:7c:bd:50:3d:b4:90:a1

  subjkey:   9c:83:b7:e9:0a:7d:dd:08:1f:2d:c5:c6:cc:63:c0:3f:96:57:a2:ce

List of X.509 CA Certificates

  subject:  "C=CZ, O=IETF, OU=SACM, CN=IETF 99 Prague Hackathon CA"

  issuer:   "C=CZ, O=IETF, OU=SACM, CN=IETF 99 Prague Hackathon CA"

  validity:  not before Jul 07 08:19:08 2017, ok

             not after  Jul 07 08:19:08 2027, ok (expires in 3651 days)

  serial:    3a:98:52:2e:75:a5:a5:8b

  flags:     CA CRLSign self-signed

  subjkeyId: 81:44:64:84:26:5f:f6:08:80:4a:c9:77:32:0e:b2:78:d0:8f:e5:84

  pubkey:    ECDSA 256 bits

  keyid:     85:94:42:42:d7:40:83:17:98:72:7f:d7:6b:4a:08:51:e8:5b:e0:63

  subjkey:   81:44:64:84:26:5f:f6:08:80:4a:c9:77:32:0e:b2:78:d0:8f:e5:84

</pre>

h2. Install Apache Web Server

An Apache web server equipped with a *Web Server Gateway Interface (WSGI)* module is installed on Ubuntu by the single command

<pre>

sudo apt install apache2 libapache2-mod-wsgi

</pre>

In order to secure the access to the web server we enable TLS

<pre>

a2enmod ssl

</pre>

h3. Configure strongTNC Virtual Web Server

In the */etc/apache2/sites-available* directory create the following configuration file and name it e.g. *tnc*:

<pre>

WSGIPythonPath /var/www/tnc

<VirtualHost *:443>

    ServerName tnc.example.com

    ServerAdmin webmaster@localhost

    DocumentRoot /var/www/tnc

    <Directory /var/www/tnc/config>

        <Files wsgi.py>

            Order deny,allow

            Allow from all

        </Files>

    </Directory>

    WSGIScriptAlias / /var/www/tnc/config/wsgi.py

    WSGIPassAuthorization On

    SSLEngine on

    SSLCertificateFile    /etc/swanctl/x509/serverCert.pem

    SSLCertificateKeyFile /etc/swanctl/ecdsa/serverKey.pem

    ErrorLog ${APACHE_LOG_DIR}/tnc/error.log

    LogLevel warn

    CustomLog ${APACHE_LOG_DIR}/tnc/access.log combined

</VirtualHost>

</pre>

The *tnc* log directory is created with

<pre>

sudo mkdir /var/log/apache2/tnc

</pre>

h2. Initialize PTS Database

I you haven't done so yet during the strongSwan TNC server installation, initialize the PTS SQLite database and give group "www-data" write permission:

<pre>

cd /usr/share/strongswan/templates/database/imv/

sudo cat tables.sql data.sql | sqlite3 /etc/pts/config.db

sudo chgrp www-data /etc/pts /etc/pts/config.db

sudo chmod g+w /etc/pts /etc/pts/config.db

</pre>

h2. Installing the strongTNC Policy Manager

strongTNC is a web application based on the "Django":https://www.djangoproject.com/ framework which itself makes use of the Python scripting language. At least Django 1.8 and Python 2.6.5 are required.  For the following installation and configuration steps we assume an Ubuntu Linux platform but the procedure on other Linux distributions is quite similar.

h3. Install strongTNC

The "strongTNC project":https://github.com/strongswan/strongTNC/ is hosted on GitHub. The latest release can be installed as follows

<pre>

wget https://github.com/strongswan/strongTNC/archive/master.zip

unzip master.zip

sudo mv strongTNC-master /var/www/tnc

sudo chown -R www-data:www-data /var/www/tnc

</pre>

h3. Install Python/Django

If not present yet, install the following Ubuntu packages

<pre>

sudo apt install python-pip python-dev libxml2-dev libxslt1-dev

</pre>

In the */var/www/tnc* directory execute the command

<pre>

sudo pip install -r requirements.txt

</pre>

which updates the Django version if necessary and installs various Python modules.

h3. Configure strongTNC

Copy *config/settings.sample.ini* to */etc/strongTNC/settings.ini* and adapt the settings to your preferences.

<pre>

[debug]

DEBUG = 1

TEMPLATE_DEBUG = 0

SQL_DEBUG = 0

DEBUG_TOOLBAR = 0

[db]

DJANGO_DB_URL = sqlite:////var/www/tnc/django.db

STRONGTNC_DB_URL = sqlite:////etc/pts/config.db

[paths]

STATIC_ROOT = static

[security]

ALLOWED_HOSTS = 127.0.0.1,tnc.example.com

CSRF_COOKIE_SECURE = 1

</pre>

Newer strongTNC versions do not come with a default django.db database where the login passwords are stored. If the database is missing create */var/www/tnc/django.db* with the following command

<pre>

sudo python /var/www/tnc/manage.py migrate --database meta

</pre>

Next set the strongTNC access passwords ("ietf99hackathon" in our example):

<pre>

sudo python /var/www/tnc/manage.py setpassword

--> Please enter a new password for admin-user: ietf99hackathon

--> Granting write_access permission.

Looking for readonly-user in database...

--> Please enter a new password for readonly-user: ietf99hackathon

Passwords updated successfully!

</pre>

In order to get a correct display of the strongTNC web pages you have to execute the following command

<pre>

sudo python /var/www/tnc/manage.py collectstatic

</pre>

h3. Start strongTNC Virtual Web Server

Now enable the virtual web server in the */etc/apache2/sites-enabled* directory and start it:

<pre>

cd /etc/apache2/sites-enabled

sudo ln -s ../sites-available/tnc tnc

sudo systemctl restart apache2

</pre>