sequence wrong size for a certificate

[Akram Chotu]

I am using below lines of code to convert a .cer file to its encoded format (not base64 encoded) :

FileInputStream is = new FileInputStream(new File("c:\\my.cer"));
CertificateFactory cf = CertificateFactory.getInstance("X.509");
java.security.cert.Certificate cert = cf.generateCertificate(is);
byte[] buf = cert.getPublicKey().getEncoded();
FileOutputStream os = new FileOutputStream("c:\\my_binary.cer");
os.write(buf);
os.close();

However when I try the reverse process of converting back to .cer file using below code:

String file = "c:\\my_binary.cer";
FileInputStream is = new FileInputStream(file);
Security.addProvider(new BouncyCastleProvider());
Provider provBC = Security.getProvider("BC");
CertificateFactory cf = CertificateFactory.getInstance("X.509", provBC);
java.security.cert.X509Certificate  cert = (X509Certificate)cf.generateCertificate(is);

then I am getting error like
java.security.cert.CertificateException: java.lang.IllegalArgumentException: sequence wrong size for a certificate


I tried with Sun's default JCE Provider but not avail. Any thoughts?


Thanks.

[greg stark]

You have clearly not stored a certificate in my_binary.cer but rather only the public key. You should change the line

byte[] buf = cert.getPublicKey().getEncoded();

to

byte[] buf = cert.getEncoded();