SSLHandshakeException when running simple SSL Java example

Question

I'm running this Java + SSL Tutorial, but I'm getting the following error.

main, handling exception: javax.net.ssl.SSLHandshakeException: Received fatal alert: certificate_unknown
javax.net.ssl.SSLHandshakeException: Received fatal alert: certificate_unknown
    at com.sun.net.ssl.internal.ssl.Alerts.getSSLException(Unknown Source)
    at com.sun.net.ssl.internal.ssl.Alerts.getSSLException(Unknown Source)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.recvAlert(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.readDataRecord(Unknown Source)
    at com.sun.net.ssl.internal.ssl.AppInputStream.read(Unknown Source)
    at sun.nio.cs.StreamDecoder.readBytes(Unknown Source)
    at sun.nio.cs.StreamDecoder.implRead(Unknown Source)
    at sun.nio.cs.StreamDecoder.read(Unknown Source)
    at java.io.InputStreamReader.read(Unknown Source)
    at java.io.BufferedReader.fill(Unknown Source)
    at java.io.BufferedReader.readLine(Unknown Source)
    at java.io.BufferedReader.readLine(Unknown Source)
    at EchoServer.main(EchoServer.java:24)

The line in the code where the exception occurs is here:

        while ((string = bufferedreader.readLine()) != null) {

What am I doing wrong here? Have things changed since that example was written?

score -2 · Accepted Answer · answered Apr 24 '12 at 21:05

-2

Probably you certificate is not valid (or not loaded) for some reason. Enabling the debug mode should help you to find more the problem

System.setProperty("javax.net.debug", "all");

Also if you're using self-sign certificates, take a look to: http://ctasada.blogspot.com.es/2010/11/httpclient-use-self-signed-certificates.html

answered Apr 24 '12 at 21:05

Carlos Tasada

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That link you're using promotes once again the usage of a trustmanager that lets anything through. Doing defeats the point of using SSL/TLS, since an active MITM could trick you and use any certificate instead, which you would trust. It also lets any host name through. It's just insecure. – Bruno Apr 24 '12 at 21:51
Well that's exactly what the article says, that's insecure. But the self-sign certificates are in secures by their own nature, that's why I'm saying to check the link only if "it's using self-sign certificates". Anyway good that you remark it. – Carlos Tasada Apr 24 '12 at 22:15
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Self-signed certificates are not insecure if you want import them explicitly, when you can verify them manually (e.g. someone gives it to you personally or you install it on your own server yourself). The danger of that sort of code in a dev. environment is that it can tick the "using SSL" box as far as project management is concerned and never be removed. There are some application with this sort of stuff remaining in production out there. It doesn't take much more work to import a self-signed certificate or, better, to have a small test CA. – Bruno Apr 24 '12 at 22:16

SSLHandshakeException when running simple SSL Java example

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