Convert RSACryptoServiceProvider RSA XML key to PKCS8

I use RSACryptoServiceProvider in my C# code, and it's working good I could Export RSA XML private and public keys, but for some reason I need to convert this key to *.pem with format (PKCS8 Unencrypted)

my private key like

<RSAKeyValue>
  <Modulus>zYs6baSaRDgLc5fG3/ozwGwS8OAvxd9quE2su+7//Lnz2WuIbe8jMc5kL7p2gsPZUEoB88SFHdGZSYiZJhERDc/1iQ4VsW2/ra8DBW+1m3K33EDvvI3rJ0NIyuRNuwoYql3hYdY0cdW6Gru9ZARCpptgBSJEiUSPjlzDEXz3RaU=</Modulus>
  <Exponent>AQAB</Exponent>
  <P>89aDVrzNZuDfkCCUR6LKlxHul64zb4EBUN4vr6VZ4LrjEqT6m7+a/8lIrgSK03R1hDdOzeg79eS0OLH5cbe6xQ==</P>
  <Q>18vAJpkwmhDSMjcPAE/4LufpZ6ukaOgkcPj9LngZSQlIt/D19LT/4NqZ2BrukX5bFCL6WPPLrJmmYlG/Jj+NYQ==</Q>
  <DP>whMgoi7PxWyCRDLKEmJNoQQSxQNPyRYCuBzAE6sl6CqXhUVuefx9H81TXb4byMXOqxdiT5zh7IrFrsJo6cv0iQ==</DP>
  <DQ>ylGZAZc2XfvPVo0QX3aadT+xMSVXq5OaNuD6XorzCerOZsZfkuHv1NyeyGHXskkJE0QH+0X3ewdDW4LQ+Ac1gQ==</DQ>
  <InverseQ>v4nkldQ2UKhJUZiyJbKnp2xopzfmreDQTTtGbaF4X0UP5pDGJndmUhj1SHITUAVqwUBa+hSl8TvzcO4IRpkOFg==</InverseQ>
  <D>JopbL9Dj7jO2DfwhGcE/7+4z1P+sZYVhbOJ/p5OGY1x4uUVdBQQIjN++0GY9r4JKnq/p0swAC9nPzMZ0tPsRP7gV5x7fmySlMP4tGpALDHbDgGfN098m2+JqK+/MIMYTAdLbnAcwk/1Lp8mB7Urm/OF/M0LOUzRQ1mwXVXNG/sE=</D>
</RSAKeyValue>

I want to convert it to (PKCS8 Unencrypted) like below

I'm not professional in this security staff, and I'm not sure could we convert it of not? could anyone help with code sample?

You can use the BouncyCastle C# library to do this. Here is an example:

using System;
using System.IO;
using System.Text;
using System.Security.Cryptography;
using Org.BouncyCastle.Security;
using Org.BouncyCastle.OpenSsl;

namespace DotNetToPkcs8Pem
{
    public class DotNetToPkcs8Pem
    {

        public static void Convert(string privXmlFilename, string privPkcs8Filename) {
            StringBuilder sb = new StringBuilder ();
            string line;
            var xmlIn = new StreamReader (privXmlFilename);
            while ((line = xmlIn.ReadLine ()) != null) {
                sb.Append (line);
            }
            var xmlKey = sb.ToString ();
            var rsa = RSA.Create ();
            rsa.FromXmlString (xmlKey);
            var bcKeyPair = DotNetUtilities.GetRsaKeyPair(rsa);
            var pkcs8Gen = new Pkcs8Generator (bcKeyPair.Private);
            var pemObj = pkcs8Gen.Generate ();
            var pkcs8Out = new StreamWriter (privPkcs8Filename, false);
            var pemWriter = new PemWriter (pkcs8Out);
            pemWriter.WriteObject (pemObj);
            pkcs8Out.Close ();
        }

        public static void Main (string[] args)
        {
            var xmlFile = "exportedDotNetPrivKey.xml";
            var pkcs8File = "privkey.pk8";
            Convert (xmlFile, pkcs8File);
        }
    }
}

来源：https://stackoverflow.com/questions/27086117/convert-rsacryptoserviceprovider-rsa-xml-key-to-pkcs8

标签

security

rsa

rsacryptoserviceprovider

pkcs#8