No more 'unable to find valid certification path to requested target'
Some of you may be familiar with the (not very user friendly) exception
message 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
when trying to open an SSL connection to a host using JSSE. What this usually means is that the server is using a test certificate (possibly generated using keytool) rather than a certificate from a well known commercial Certification Authority such as Verisign or GoDaddy. Web browsers display warning dialogs in this case, but since JSSE cannot assume an interactive user is present it just throws an exception by default.
Certificate validation is a very important part of SSL security, but I am not writing this entry to explain the details. If you are interested, you can start by reading the Wikipedia blurb. I am writing this entry to show a simple way to talk to that host with the test certificate, if you really want to.
Basically, you want to add the server's certificate to the KeyStore with
your trusted certificates. There are any number of ways to achieve
that, but a simple solution is to compile and run the
attached
program as
java InstallCert hostname
, for example
Loading?KeyStore?/usr/jdk/instances/jdk1 .5.0 /jre/lib/security/cacerts

Opening?connection?to?ecc.fedora.redhat.com: 443

Starting?SSL?handshake

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(Alerts.java: 150 )
????at?com.sun.net.ssl.internal.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java: 1476 )
????at?com.sun.net.ssl.internal.ssl.Handshaker.fatalSE(Handshaker.java: 174 )
????at?com.sun.net.ssl.internal.ssl.Handshaker.fatalSE(Handshaker.java: 168 )
????at?com.sun.net.ssl.internal.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java: 846 )
????at?com.sun.net.ssl.internal.ssl.ClientHandshaker.processMessage(ClientHandshaker.java: 106 )
????at?com.sun.net.ssl.internal.ssl.Handshaker.processLoop(Handshaker.java: 495 )
????at?com.sun.net.ssl.internal.ssl.Handshaker.process_record(Handshaker.java: 433 )
????at?com.sun.net.ssl.internal.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java: 815 )
????at?com.sun.net.ssl.internal.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java: 1025 )
????at?com.sun.net.ssl.internal.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java: 1038 )
????at?InstallCert.main(InstallCert.java: 63 )
Caused?by:?sun.security.validator.ValidatorException:?PKIX?path?building?failed:?sun.security.provider.certpath.SunCertPathBuilderException:
unable?to?find?valid?certification?path?to?requested?target
????at?sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java: 221 )
????at?sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java: 145 )
????at?sun.security.validator.Validator.validate(Validator.java: 203 )
????at?com.sun.net.ssl.internal.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java: 172 )
????at?InstallCert$SavingTrustManager.checkServerTrusted(InstallCert.java: 158 )
????at?com.sun.net.ssl.internal.ssl.JsseX509TrustManager.checkServerTrusted(SSLContextImpl.java: 320 )
????at?com.sun.net.ssl.internal.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java: 839 )
????

Caused?by:?sun.security.provider.certpath.SunCertPathBuilderException:?unable?to?find?valid?certification?path?to?requested?target
????at?sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java: 236 )
????at?java.security.cert.CertPathBuilder.build(CertPathBuilder.java: 194 )
????at?sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java: 216 )
????

Server?sent? 2 ?certificate(s):
? 1 ?Subject?CN = ecc.fedora.redhat.com , ?O = example.com , ?C = US
???Issuer??CN = Certificate?Shack , ?O = example.com , ?C = US
???sha1????2e?7f? 76 ?9b? 52 ? 91 ? 09 ?2e?5d?8f?6b? 61 ? 39 ?2d?5e? 06 ?e4?d8?e9?c7?
???md5?????dd?d1?a8? 03 ?d7?6c?4b? 11 ?a7?3d? 74 ? 28 ? 89 ?d0? 67 ? 54 ?
? 2 ?Subject?CN = Certificate?Shack , ?O = example.com , ?C = US
???Issuer??CN = Certificate?Shack , ?O = example.com , ?C = US
???sha1????fb? 58 ?a7? 03 ?c4?4e?3b?0e?e3?2c? 40 ?2f? 87 ? 64 ? 13 ?4d?df?e1?a1?a6?
???md5????? 72 ?a0? 95 ? 43 ?7e? 41 ? 88 ? 18 ?ae?2f?6d? 98 ? 01 ?2c? 89 ? 68 ?
Enter?certificate?to?add?to?trusted?keystore?or?'q'?to?quit:? [ 1 ]
What happened was that the program opened a connection to the specified host and started an SSL handshake. It printed the exception stack trace of the error that occured and shows you the certificates used by the server. Now it prompts you for the certificate you want to add to your trusted KeyStore. You should only do this if you are sure that this is the certificate of the trusted host you want to connect to. You may want to check the MD5 and SHA1 certificate fingerprints against a fingerprint generated on the server (e.g. using keytool) to make sure it is the correct certificate.
If you've changed your mind, enter 'q'. If you really want to add the certificate, enter '1'. (You could also add a CA certificate by entering a different certificate, but you usually don't want to do that'). Once you have made your choice, the program will print the following:
...Added certificate to keystore 'jssecacerts' using alias 'ecc.fedora.redhat.com-1'
It displayed the complete certificate and then added it to a Java
KeyStore 'jssecacerts' in the current directory. To use it in your
program, either configure JSSE to use it as its trust store (as
explained in the
documentation)
or copy it into your $JAVA_HOME/jre/lib/security
directory. If you want all Java applications to recognize the
certificate as trusted and not just JSSE, you could also overwrite the cacerts
file in that directory.
After all that, JSSE will be able to complete a handshake with the host, which you can verify by running the program again:

?Opening?connection?to?ecc.fedora.redhat.com:443

?Starting?SSL?handshake

?No?errors,?certificate?is?already?trusted?Server?sent?2?certificate(s):?1?[

Enter?certificate?to?add?to?trusted?keystore?or?'q'?to?quit:?[1]?q?KeyStore?not?changed?
posted on 2010-02-09 14:55 ideame 閱讀(1529) 評論(1) 編輯 收藏 所屬分類: Configuration