Reputation: 18511
I need a RSA public key encoded into DER format.
The key-pair is generated using RSACryptoServiceProvider.
What I'm looking for is the c# equivalent to the java:
PublicKey pubKey = myPair.getPublic();
byte[] keyBytes = pubKey.getEncoded();
I have tried looking into BouncyCastle but got lost so if the solution is there any pointers are welcome.
Upvotes: 2
Views: 2894
Reputation: 3
I tried to use aforementioned info.GetEncoded() but as a result, I couldn't use it to verify the signature created with the corresponding private key.
What works for me is converting it to a X509Certificate2.
private bool VerifySignature(string stringContent, string stringSignature, X509Certificate2 x509PublicKey)
{
Int16 cbSignature = 0, cbCert = 0;
int cbData = 0;
CertBasicStruct sCert = new CertBasicStruct();
var pbCert = PublicKey.RawData;
cbCert = (Int16)pbCert.Length;
byte[] pbData = Encoding.UTF8.GetBytes(stringContent);
cbData = (Int16)pbData.Length;
byte[] pbSignature = Convert.FromBase64String(Signature);
cbSignature = (Int16)pbSignature.Length;
var rtn = DllImportService.DecodeCertificate(pbCert, cbCert, ref sCert);
var rtn_1 = DllImportService.VerifySignatureByCert(ref sCert, DllImportService.CKM_SHA256_RSA_PKCS, pbData, cbData, pbSignature, cbSignature);
if (rtn_1 == 0)
{
LogWndAppendLine("Signature is valid.");
return true;
}
else
{
LogWndAppendLine("Signature is invalid");
return false;
}
}
X509Certificate2.RawData would be what you are looking for.
Upvotes: 0
Reputation: 18511
Using Bouncy Castle:
using Org.BouncyCastle.X509;
using Org.BouncyCastle.Security;
using Org.BouncyCastle.Crypto;
using Org.BouncyCastle.Crypto.Generators;
using Org.BouncyCastle.Crypto.Parameters;
...
var generator = new RsaKeyPairGenerator ();
generator.Init (new KeyGenerationParameters (new SecureRandom (), 1024));
var keyPair = generator.GenerateKeyPair ();
RsaKeyParameters keyParam = (RsaKeyParameters)keyPair.Public;
var info = SubjectPublicKeyInfoFactory.CreateSubjectPublicKeyInfo (keyParam);
RsaBytes = info.GetEncoded ();
The last three lines are the ones who take the RSA public key and export it.
Upvotes: 4