Re: Pass X509Certificate as String?

From:
=?ISO-8859-1?Q?Arne_Vajh=F8j?= <arne@vajhoej.dk>
Newsgroups:
comp.lang.java.programmer
Date:
Fri, 08 Feb 2013 19:35:49 -0500
Message-ID:
<511599e8$0$293$14726298@news.sunsite.dk>
On 2/8/2013 7:21 PM, Arne Vajh?j wrote:

On 2/8/2013 7:12 PM, Arne Vajh?j wrote:

On 2/8/2013 6:48 PM, Ian Pilcher wrote:

This is a bit weird. I am writing an SSLSocketFactory for use with the
PostgreSQL JDBC driver. Unfortunately, the driver imposes some very
inconvenient criteria on the factory class.

   http://jdbc.postgresql.org/documentation/91/ssl-factory.html

In particular, the class must have a zero-argument constructor or a
constructor that takes a single String argument. My challenge is to
somehow pass a java.security.cert.X509Certificate to this constructor.

The only idea I've been able to come up with thus far is to serialize
the certificate to a ByteArrayOutputStream, convert that to a String,
and reverse the process in the constructor.

Does anyone have a better idea?


I believe it is common to use Bas64 encoding of DER encoding
of the certificate.

Maybe you can use that!?


The methods must be getInstance and getEncoded.


Code snippet:

     public static String b64encode(byte[] b) throws MessagingException,
IOException {
         ByteArrayOutputStream baos = new ByteArrayOutputStream();
         OutputStream b64os = MimeUtility.encode(baos, "base64");
         b64os.write(b);
         b64os.close();
         return new String(baos.toByteArray());
      }
      public static byte[] b64decode(String s) throws
MessagingException, IOException {
         ByteArrayInputStream bais = new ByteArrayInputStream(s.getBytes());
         InputStream b64is = MimeUtility.decode(bais, "Base64");
         byte[] tmp = new byte[s.length()];
         int n = b64is.read(tmp);
         byte[] res = new byte[n];
         System.arraycopy(tmp, 0, res, 0, n);
         return res;
      }
    public static String encode(X509Certificate cert) throws
CertificateEncodingException, MessagingException, IOException {
        return b64encode(cert.getEncoded());
    }
    public static X509Certificate decode(String s) throws
CertificateException, MessagingException, IOException {
        return X509Certificate.getInstance(b64decode(s));
    }

Arne

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