This page consists of an SSL error message troubleshooting reference followed by a discussion of SSL in Java that puts many of the solutions in context.
Troubleshooting SSL Errors
This section contains the most often-cited SSL errors reported by the CAS server and CAS clients in typical CAS integration scenarios.
PKIX path building failed
Sep 28, 2009 4:13:26 PM org.jasig.cas.client.validation.AbstractCasProtocolUrlBasedTicketValidator retrieveResponseFromServer
SEVERE: javax.net.ssl.SSLHandshakeException:
sun.security.validator.ValidatorException: PKIX path building failed:
sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
javax.net.ssl.SSLHandshakeException:
sun.security.validator.ValidatorException: PKIX path building failed:
sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at com.sun.net.ssl.internal.ssl.Alerts.getSSLException(Unknown Source)
at com.sun.net.ssl.internal.ssl.SSLSocketImpl.fatal(Unknown Source)
at com.sun.net.ssl.internal.ssl.Handshaker.fatalSE(Unknown Source)
at com.sun.net.ssl.internal.ssl.Handshaker.fatalSE(Unknown Source)
at com.sun.net.ssl.internal.ssl.ClientHandshaker.serverCertificate(Unknown Source)
at com.sun.net.ssl.internal.ssl.ClientHandshaker.processMessage(Unknown Source)
at com.sun.net.ssl.internal.ssl.Handshaker.processLoop(Unknown Source)
at com.sun.net.ssl.internal.ssl.Handshaker.process_record(Unknown Source)
at com.sun.net.ssl.internal.ssl.SSLSocketImpl.readRecord(Unknown Source)
at com.sun.net.ssl.internal.ssl.SSLSocketImpl.performInitialHandshake(Unknown Source)
at com.sun.net.ssl.internal.ssl.SSLSocketImpl.startHandshake(Unknown Source)
at com.sun.net.ssl.internal.ssl.SSLSocketImpl.startHandshake(Unknown Source)
at sun.net.www.protocol.https.HttpsClient.afterConnect(Unknown Source)
at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(Unknown Source)
at org.jasig.cas.client.validation.AbstractCasProtocolUrlBasedTicketValidator.retrieveResponseFromServer(AbstractCasProtocolUrlBasedTicketValidator.java:35)
at org.jasig.cas.client.validation.AbstractUrlBasedTicketValidator.validate(AbstractUrlBasedTicketValidator.java:178)
at org.jasig.cas.client.validation.AbstractTicketValidationFilter.doFilter(AbstractTicketValidationFilter.java:132)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
PKIX path building errors are by far the most common SSL errors reported on the cas-user@lists.jasig.org mailing list. The problem here is that the CAS client does not trust the certificate presented by the CAS server; most often this occurs because of using a self-signed certificate on the CAS server. To resolve this error, import the CAS server certificate into the system truststore of the CAS client. If the certificate is issued by your own PKI, it is better to import the root certificate of your PKI into the CAS client truststore. See #Import Trusted Certificate for examples of importing a trusted certificate into a Java truststore.
No subject alternative names present
javax.net.ssl.SSLHandshakeException: java.security.cert.CertificateException: No subject alternative names present
In most cases this is a hostname/SSL certificate CN mismatch. This commonly happens when a self-signed certificate issued to localhost is placed on a machine that is accessed by IP address. It should be noted that generating a certificate with an IP address for a common name, e.g. CN=192.168.1.1,OU=Middleware,dc=vt,dc=edu, will not work in most cases where the client making the connection is Java. For example the Java CAS client will throw SSL errors on connecting to a CAS server secured with a certificate containing an IP address in the CN.
HTTPS hostname wrong
ava.lang.RuntimeException: java.io.IOException: HTTPS hostname wrong: should be <eiger.iad.vt.edu> org.jasig.cas.client.validation.Saml11TicketValidator.retrieveResponseFromServer(Saml11TicketValidator.java:203) org.jasig.cas.client.validation.AbstractUrlBasedTicketValidator.validate(AbstractUrlBasedTicketValidator.java:185) org.jasig.cas.client.validation.AbstractTicketValidationFilter.doFilter(AbstractTicketValidationFilter.java:132) org.jasig.cas.client.authentication.AuthenticationFilter.doFilter(AuthenticationFilter.java:102)
The above error occurs most commonly when the CAS client ticket validator attempts to contact the CAS server and is presented a certificate whose CN does not match the fully-qualified host name of the CAS server. There are a few common root causes of this mismatch:
- CAS client misconfiguration (usually a bad serverName init param)
- Complex multi-tier server environment (e.g. clustered CAS server)
- Host name too broad for scope of wildcard certificate
Wildcard Certificates
JSSE support for wildcard certificates is limited to hosts strictly in the same domain as the wildcard. For example, a certificate with CN=*.vt.edu matches hosts a.vt.edu and b.vt.edu, but not a.b.vt.edu.
Simplified Java SSL Guide
The following guide attempts to distill the most important aspects of the Java Secure Socket Extension Reference Guide into a series of brief topics for consideration by CAS deployers. The following content should be considered a general guide with practical application to CAS through discussion and examples that are CAS-specific.
TODO: Write this content before or during the Spring Jasig Conference - MSA.
Keystore/TrustStore Reference
Import Trusted Certificate
By default the Java system truststore is at $JAVA_HOME/jre/lib/security/cacerts. The certificate to be imported MUST be a DER-encoded file. If the contents of the certificate file are binary, it's likely DER-encoded; if the file begins with the text -----BEGIN CERTIFICATE-----, it is PEM-encoded and needs to be converted to DER encoding. The following example demonstrates a conversion command using OpenSSL.
openssl x509 -in etc/pki/incommon-root-cert.pem -out tmp/incommon-root-cert.der -outform DER
Once the certificate file is properly in the DER-encoded format, it may be imported using the keytool command.
keytool -import -keystore $JAVA_HOME/jre/lib/security/cacerts -file tmp/incommon-root-cert.der -alias incommon
List Trusted Certificates
keytool -v -list -keystore $JAVA_HOME/jre/lib/security/cacerts
Alternatives to Sun keytool Utility
- Portecle is a Java GUI tool that can handle all the keystore and certificate formats I've ever encountered. Very easy to use and recommended if you are uncomfortable with CLI tools.
- keystore is a CLI tool that has a couple notable improvements on keytool:
- Support for both PEM and DER-encoded files.
- You can import a certificate/key pair directly into a keystore. (With keytool, keys never leave the keystore; you generate them, then a corresponding CSR, then import the matching certificate once it is issued.)