Back to the beginning of this guide
Table of contents for step 1
Install pre-requisites
Install required (and used, throughout this documentation) packages, possibly replacing vim with your $EDITOR of choice (e.g. emacs-nox or nano, both of which also support syntax highlighting, which helps when editing XML files) and stop the automatically started tomcat until we've completed more configuration performed below:
apt install --no-install-recommends default-jdk-headless tomcat9 \ vim less openssl unzip curl expat multitail gnupg net-tools systemctl stop tomcat9
Post-install fix-ups
Redirect requests to Tomcat's web root ("/") to a URL of your choice, e.g. your institution's home page, replacing "www.example.edu" in the command below. The Shibboleth IDP application by default will run at /idp, allowing you to easily add and update other content outside of /idp, e.g. logos or CSS stylesheets without having them to integrate them with the "idp" context/application. The document root for that is in /var/lib/tomcat9/webapps/ROOT/ and nothing in the Shibboleth IDP software (or during use of SAML) by default links to / of the server, so you can use that for locally hosted content without interfering with the IDP application. For example, you will want to add a robots.txt file to avoid unnecessary scanning by well-behaved search bots.
rm /var/lib/tomcat9/webapps/ROOT/index.html
echo '<% response.sendRedirect("https://www.example.edu"); %>' > /var/lib/tomcat9/webapps/ROOT/index.jsp
echo -e "User-agent: *\nDisallow: /" > /var/lib/tomcat9/webapps/ROOT/robots.txt
Set JAVA_HOME for the current (and future) shell(s):
eval $(echo "export JAVA_HOME=/usr" | tee /etc/profile.d/java.sh)
Enable TLS/SSL
Create keypair and certificate chain
Do not use an existing wildcard certificate (if one is available that would also cover your IDP webserver) – just do the work as described below and create another certificate for your IDP. Under ACOnet's TCS agreement you can get unlimited globally valid commercial certificates at no cost to you. (Alternatively, though not recommended for your eduID.at IDP, there's always letsencrypt.) So there should be no excuse to promiscuously share an existing TLS key pair across unrelated servers and services.
First, create and note down a random passphrase to use for protecting/encrypting the private key at rest. (Use this passphrase in all the steps below when asked for a key passphrase or import/export password.)
openssl rand -hex 16
On the IDP server create an RSA private key of at least 2048 bits size and the CSR for the web server's TLS certificate, supplying the necessary data (at least the subject) on the command line or by entering any data interactively when being prompted for it (when not adding -subj to the command):
openssl req -new -newkey rsa:2048 -out webserver.csr -keyout webserver.key -subj "/CN=WEBSERVER-FQDN"
When asked to "Enter pass phrase for webserver.key" provide the passphrase from the previous step.
Renewing an existing TLS certificate?
In case you're replacing an expiring TLS certificate where the matching private key is still considered to be secure and of sufficient strength (in 2021 for RSA keys that means a key size of at least 2048 bits) you may want to keep using the existing private key (and PKCS#12 keystore passphrase) and generate the CSR from that key.
To do that first extract the private key from your keystore (instead of generating a new one):
openssl pkcs12 -in /etc/tomcat9/webserver.p12 -nocerts | tail +5 > webserver.key
When asked to "Enter Import Password" supply the existing keystorePass for the port="443" Connector from your /etc/tomcat9/server.xml configuration file.
When asked to "Enter PEM pass phrase" simply enter/paste that same passphrase again.
And yet again, when asked to "Verifying - Enter PEM pass phrase".
Then generate a CSR from the extracted private key, either by supplying the necessary data (at least the subject) on the command line or by entering any data interactively when being prompted for it (when not adding -subj to the command):
openssl req -new -key webserver.key -out webserver.csr -subj "/CN=WEBSERVER-FQDN"
When asked to "Enter pass phrase for webserver.key" again provide the passphrase from the previous steps.
The content of webserver.csr is what you provide to your CA then, e.g. via cat webserver.csr and pasting the result into the CA's web interface.
Equipped with the CSR you can now request a TLS certificate based from your CA, e.g. using the ACOnet TCS supplier. Once the certificate has been issued copy it to the IDP server as webserver.crt.
You'll also need to copy any intermediate Certificate Authority (CA) certificates to the IDP server.
In case of ACOnet TCS, Sectigo and an RSA OV certificate the only intermediate CA certificate you'll need is the one with the subject "C = NL, O = GEANT Vereniging, CN = GEANT OV RSA CA 4", referenced as file GEANT-OV-RSA-CA-4.crt below.
Convert the TLS/SSL keypair into PKCS12
Copy the private key, new TLS certificate and any intermediate CA certificates into a PKCS#12 keystore file:
openssl pkcs12 -export -in webserver.crt -inkey webserver.key -certfile GEANT-OV-RSA-CA-4.crt -name "webserver" -out webserver.p12
When asked to "Enter pass phrase for webserver.key" provide the passphrase generated earlier.
Again when asked to "Enter Export Password".
And yet again, when asked to "Verifying - Enter Export Password".
Move the newly created keystore to its final location (we're chosing Tomcat's config directory) and set strict file system permissions on it:
[[ -f /etc/tomcat9/webserver.p12 ]] && cp -a /etc/tomcat9/webserver.p12 /etc/tomcat9/webserver.p12.`date -u +%Y%m%d` mv webserver.p12 /etc/tomcat9/ chown root:tomcat /etc/tomcat9/webserver.p12 chmod 640 /etc/tomcat9/webserver.p12
Configure Tomcat Connector
Remove or comment out all other Connectors in /etc/tomcat9/server.xml, then add the two Connectors as per below, replacing keystorePass with the password generated earlier:
If you still need to support clients that can only speak TLS 1.0 or TLS 1.1 you will have to amend the sslEnabledProtocols parameter below!
<!-- Localhost-only connector for IDP command line tools --> <Connector address="127.0.0.1" port="80" /> <!-- https://tomcat.apache.org/tomcat-9.0-doc/ssl-howto.html --> <Connector port="443" protocol="org.apache.coyote.http11.Http11NioProtocol" maxThreads="150" maxPostSize="100000" SSLEnabled="true" scheme="https" secure="true" clientAuth="false" sslProtocol="TLS" sslEnabledProtocols="TLSv1.2,TLSv1.3" keystoreType="pkcs12" keystoreFile="/etc/tomcat9/webserver.p12" keystorePass="see above"> <UpgradeProtocol className="org.apache.coyote.http2.Http2Protocol" /> </Connector>
Start Tomcat, check for listening ports, and access https://webserver-fqdn/foo which should result in an HTTP Status 404 error (since /foo won't exist) but allows you to confirm a hopefully valid TLS/SSL webserver configuration:
systemctl restart tomcat9 netstat -lntp | fgrep java # should show 443, and 80 only on the loopback interface
Verify TLS/SSL
Next validate the TLS/SSL configuration on the system itself with openssl (and quit again with ctrl-c or by typing QUIT into the prompt):
openssl s_client -CApath /etc/ssl/certs/ -connect webserver-fqdn:443 </dev/null
Look for "Certificate chain" in the output from that command, e.g.
openssl s_client -CApath /etc/ssl/certs/ -connect webserver-fqdn:443 2>&1 </dev/null | grep -A8 "^Certificate chain"
and verify that it looks something like the "Certificate chain" presented below. The Subject of cert 0 will obviously differ, and depending on your choice of CA or certificate product the CA or certificate chain may also be different. A correct chain (and therfore PKCS#12 keystore) for TLS usage should contain all the certificates up until but excluding the root CA certificate. I.e, in the example below the certificate with CN=USERTrust RSA Certification Authority is not included in the chain sent from the server (but must be known by the web browser):
Certificate chain 0 s:C = AT, postalCode = 1010, ST = Wien, L = Wien, street = Universitaetsstrasse 7, O = ACOnet, CN = idp.aco.net i:C = NL, O = GEANT Vereniging, CN = GEANT OV RSA CA 4 1 s:C = NL, O = GEANT Vereniging, CN = GEANT OV RSA CA 4 i:C = US, ST = New Jersey, L = Jersey City, O = The USERTRUST Network, CN = USERTrust RSA Certification Authority
In case of errors check the output of "journalctl -u tomcat9 -ef".
If everything works fine and the certificate chain looks as expected you can remove the private key and certificate again (as both can be extracted from the PKCS#12 keystore if needed), keeping the CSR in file webserver.csr around for next time you need to renew that certificate (as long as you still consider the matching private key secure):
rm webserver.{key,crt}
Tune log file creation
IDP logs
You might prefer to have the IDP application write its logs to a more standard file system location in the file system, specifically one outside the application's own directory and on a file system that where data usage is expected to grow dynamically (e.g. on /var). To do that simply set the idp.logfiles property in any of the property files read by the IDP, e.g. within conf/idp.properties:
idp.logfiles=/var/log/shibboleth
We also have to create that directory. And in order for the example commands in this documentation to work with either log directory we'll remove the (still empty) log dir created by the IDP installer and replace it with a symlink to the actual log directory:
install -o tomcat -g root -m 0750 -d /var/log/shibboleth/ cd /opt/shibboleth-idp/ && rmdir logs && ln -s /var/log/shibboleth logs
Tomcat logs
By default Tomcat logs additional (and duplicate) events to /var/log/tomcat9/catalina.$date.log and /var/log/tomcat9/localhost.$date.log, which we don't care for. So let's create a backup copy of Tomcat's logging.properties and replace its content with the minumum needed to get an access log comparable to Apache httpd written to /var/log/tomcat9/access.log. Tomcat's stdout/stderr will go to the systemd journal.
systemctl stop tomcat9 cp -a /etc/tomcat9/logging.properties /etc/tomcat9/logging.properties.orig echo -n 'handlers = org.apache.juli.FileHandler, java.util.logging.ConsoleHandler org.apache.juli.FileHandler.level = SEVERE org.apache.juli.FileHandler.rotatable = false org.apache.juli.FileHandler.directory = /dev org.apache.juli.FileHandler.prefix = null org.apache.juli.FileHandler.suffix = java.util.logging.ConsoleHandler.level = INFO java.util.logging.ConsoleHandler.formatter = java.util.logging.SimpleFormatter org.apache.catalina.core.ContainerBase.[Catalina].[localhost].level = INFO org.apache.catalina.core.ContainerBase.[Catalina].[localhost].handlers = org.apache.juli.FileHandler ' > /etc/tomcat9/logging.properties
Then comment out or delete the whole Valve element at the end of your /etc/tomcat9/server.xml, and replace it with the following one:
<Valve className="org.apache.catalina.valves.AccessLogValve" maxLogMessageBufferSize="320"
prefix="access" suffix=".log" renameOnRotate="true" pattern="combined" />
After deleting all Tomcat logs (only) access.log should be generated in Tomcat's log directory going forward:
rm -f /var/log/tomcat9/* systemctl restart tomcat9 ls -l /var/log/tomcat9/ multitail /var/log/tomcat9/* -l 'journalctl -u tomcat9.service -f' # exit with 'q' systemctl stop tomcat9
Since there's no catalina.log file anymore we can also disable the default logrotate config snippet for it:
sed -i 's/^/#/' /etc/logrotate.d/tomcat9
Systemd service
Debian 10's Tomcat comes with an almost-usable systemd service that needs to be amended in order to
- avoid the systemd-house-of-horror that's still all too common with Tomcat packaging, and
- allow the IDP application to write logs and metadata to the filesystem as needed.
And since we're creating an override for the system-supplied systemd service unit anyway we'll also set the maximum memory usage ("-Xmx3g" in the example below, i.e., 3GB). Adjust as needed, but 3-4GB should be sufficient. Also leave a bit of RAM for the OS. 
(Not that you should be running anything else on an IDP server.)
install -o root -g root -m 0755 -d /etc/systemd/system/tomcat9.service.d
cat <<'EOF' > /etc/systemd/system/tomcat9.service.d/override.conf
[Service]
Environment="JAVA_OPTS=-Djava.security.egd=file:/dev/urandom -Djava.awt.headless=true -Xmx3g"
Environment="JSSE_OPTS=-Djdk.tls.ephemeralDHKeySize=2048"
ExecStart=
ExecStart=/usr/bin/java \
$JAVA_OPTS $JSSE_OPTS \
-classpath ${CATALINA_HOME}/bin/bootstrap.jar:${CATALINA_HOME}/bin/tomcat-juli.jar \
-Dcatalina.base=${CATALINA_BASE} \
-Dcatalina.home=${CATALINA_HOME} \
-Djava.util.logging.config.file=${CATALINA_BASE}/conf/logging.properties \
-Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager \
-Djava.io.tmpdir=${CATALINA_TMPDIR} \
org.apache.catalina.startup.Bootstrap
ReadWritePaths=/var/log/shibboleth/
ReadWritePaths=/opt/shibboleth-idp/logs/
ReadWritePaths=/opt/shibboleth-idp/metadata/
EOF
(If you've set "idp.logfiles=/var/log/shibboleth" via the IDP's property files as described in section "IDP logs" above you can remove the line that allows Tomcat to write to /opt/shibboleth-idp/logs/. The above example config just makes sure IDP logs can get written using either log location.)
Activate the override with systemctl daemon-reload, maybe also verify with systemd-delta | fgrep tomcat
Overview
Content Tools
Tasks