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Java RSA-OAEP generate key pair

I am trying to interface with external system which requires to send an RSA-OAEP SHA-256 public key with key size of 2048.
I am getting an error that the key has wrong bit length: '2350' .
I tried online encryption/decryption services using the generated KP and they seems to accept the key. What I am doing wrong?
Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
SecureRandom random = new SecureRandom();
KeyPairGenerator generator = KeyPairGenerator.getInstance("RSA", "BC");
generator.initialize(2048, random);
KeyPair pair = generator.generateKeyPair();
Key pubKey = pair.getPublic();
Key privKey = pair.getPrivate();
// I am sending pubKey.getEncoded()
Example result of the public key:
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAuUKRnE07rwQ8Juegbhabv1kaHOrfou8+FNHYyhjn8jUPgwumALonsvztt4goivc1Bwm6sFwCIGnxf+2y1BI1saG3w5S1R24EUAN7efi7CS4LMEhtgJtavtWYEkEZj7OaU/BLnkB1rFAmBDU3vudSd3Gupgnbqtw7VjOH6Qrfnsh3phVr6DdHruq7SftOvCyhBucOax0hwt6enRs5UjBfbgDbbSMFaFdF4jZpE4Jnfl9gwRF51QP934Il1djPT6cezuEYlD8VAklLFPR+rOL73nvBCxLdZwdBlQHO8J8XGjWaNmAMHvyisFxkD8Ud9nC7m9MPb9J6+n3cWG7OL+C97QIDAQAB
Thank you

Creating an armored ECC public/private keys in android studio from spongy castle library (OpenPGP)

My goal is to create Elliptical curve key pairs from it using spongy castle library and then armor it.
X9ECParameters curve = ECNamedCurveTable.getByName("secp256k1");
ECDomainParameters domainParams = new ECDomainParameters(curve.getCurve(),curve.getG(), curve.getN(), curve.getN(), curve.getSeed());
SecureRandom secureRandom = new SecureRandom();
ECKeyGenerationParameters keyParams = new ECKeyGenerationParameters(domainParams, secureRandom);
ECKeyPairGenerator generator = new ECKeyPairGenerator();
generator.init(keyParams);
AsymmetricCipherKeyPair kp= generator.generateKeyPair();
char[] passPhrase = "hello".toCharArray();
PGPKeyPair ecKeyPair = new BcPGPKeyPair(PGPPublicKey.ECDH, kp, new Date());
PGPKeyRingGenerator keyRingGen = new PGPKeyRingGenerator
(PGPSignature.DEFAULT_CERTIFICATION,
ecKeyPair,
"umaimaahmed1#gmail.com", null, null,
null, new BcPGPContentSignerBuilder(PGPPublicKey.EC,
HashAlgorithmTags.SHA256),
new BcPBESecretKeyEncryptorBuilder(PGPEncryptedData.AES_256).build(passPhrase));
After this the parsed armored key ring generation is executed.
It works fine for RSA but for ECC implementation I get an exception of illegal object in getInstance: org.spongycastle.asn1.x9.X962Parameters
when it hits the linePGPKeyPair ecKeyPair = new BcPGPKeyPair(PGPPublicKey.ECDH, kp, new Date());
I cant find anything on the internet to generate PGP Key Rings from ECC key pairs.

Generating keyPair using Bouncy Castle

I have Java code for generating keypair using BC as follows:
KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA");
keyGen.initialize(1024);
KeyPair key = keyGen.generateKeyPair();
PrivateKey priv = key.getPrivate();
PublicKey pub = key.getPublic();
String privateKey = new String(Base64.encode(priv.getEncoded(), 0,priv.getEncoded().length, Base64.NO_WRAP));
String publicKey1 = new String(Base64.encode(pub.getEncoded(), 0,pub.getEncoded().length, Base64.NO_WRAP));
String publicKey = new String(Base64.encode(publicKey1.getBytes(),0, publicKey1.getBytes().length, Base64.NO_WRAP));
Now I want to do same in C# using BC. I have downloaded WP8BouncyCastle library via nuget package manager. I have written as:
var kpgen = new RsaKeyPairGenerator();
kpgen.Init(new KeyGenerationParameters(new SecureRandom(new CryptoApiRandomGenerator()), 1024));
var keyPair = kpgen.GenerateKeyPair();
AsymmetricKeyParameter privateKey = keyPair.Private;
AsymmetricKeyParameter publicKey = keyPair.Public;
string prvKey = Convert.ToBase64String(UTF8Encoding.UTF8.GetBytes(privateKey.ToString()));
string pubKey = Convert.ToBase64String(UTF8Encoding.UTF8.GetBytes(publicKey.ToString()));
string pubKey1 = Convert.ToBase64String(UTF8Encoding.UTF8.GetBytes(pubKey.ToString()));
But I need getEncoded() method available in Java which is not available in BC library in C#. This getEncoded() method is used to convert given key into X.509 encoded key.In case of Java, public key getting twice converted (getencoded() and getBytes()) ,I am not able to do same in C#.
Is there any solution to it?

Use the following code for private key:
PrivateKeyInfo pkInfo = PrivateKeyInfoFactory.CreatePrivateKeyInfo(keyPair.Private);
String privateKey = Convert.ToBase64String(pkInfo.GetDerEncoded());
and following for public:
SubjectPublicKeyInfo info = SubjectPublicKeyInfoFactory.CreateSubjectPublicKeyInfo(keyPair.Public);
String publicKey = Convert.ToBase64String(info.GetDerEncoded());

Exception when Constructing EncryptedPrivateKeyInfo

I have generated a private key and encrypted it with a password. Now I want to load it to EncryptedPrivateKeyInfo, so that I can construct and export it into a PEM format file. Below is the code I use,
final CertAndKeyGen keypair = new CertAndKeyGen("RSA", "SHA1WithRSA", null);
final X500Name x500Name =
new X500Name("IN", "AP", "HYD", "TEST", "TEST_ORG", "test#xyz.com");
keypair.generate(1024);
final PrivateKey privKey = keypair.getPrivateKey();
final X509Certificate[] chain = new X509Certificate[1];
long validity = 123;
chain[0] = keypair.getSelfCertificate(x500Name, new Date(),
validity * 24 * 60 * 60);
Key key = new SecretKeySpec(password.getBytes(), ALGO);
Cipher c = Cipher.getInstance(ALGO);
c.init(Cipher.ENCRYPT_MODE, key);
byte[] encVal = c.doFinal(privKey.getEncoded());
AlgorithmParameters params = AlgorithmParameters.getInstance("DES");
params.init(encVal); // <--- exception thrown here
EncryptedPrivateKeyInfo encinfo = new EncryptedPrivateKeyInfo(params, encVal);
// displaying encrypting value
String encryptedValue = Base64.encodeBase64String(encinfo.getEncoded());
System.out.println(encryptedValue);
But while executing the above code, I get the below exception
java.io.IOException: DER input not an octet string
at sun.security.util.DerInputStream.getOctetString(DerInputStream.java:233)
at com.sun.crypto.provider.SunJCE_t.a(DashoA13*..)
at com.sun.crypto.provider.DESParameters.engineInit(DashoA13*..)
at java.security.AlgorithmParameters.init(AlgorithmParameters.java:260)
in the line params.init(encVal);. I don't get what's going wrong from the exception. Any help or suggestion will be really appreciated. Thanks in advance.

A PKCS #8 file containing an encrypted private key has the following ASN.1 structure:
EncryptedPrivateKeyInfo ::= SEQUENCE {
encryptionAlgorithm EncryptionAlgorithmIdentifier,
encryptedData EncryptedData }
Notice how the encrypted data is only part of the total data package. You need to include this data in a sequence along with the encryption algorithm identifier. Your code above produces only the encryptedData part.
I would suggest you consider using BouncyCastle. It looks like they may have improved support for PKCS#8 recently. Here's some sample code:
KeyPairGenerator generator = KeyPairGenerator.getInstance("RSA");
KeyPair keyPair = generator.generateKeyPair();
final PrivateKey privKey = keyPair.getPrivate();
JceOpenSSLPKCS8EncryptorBuilder builder =
new JceOpenSSLPKCS8EncryptorBuilder(PKCS8Generator.PBE_SHA1_3DES);
builder.setIterationCount(10000);
builder.setPasssword("Hello, World!".toCharArray());
OutputEncryptor outputEncryptor = builder.build();
PKCS8Generator pkcs8Generator =
new JcaPKCS8Generator(privKey, outputEncryptor);
try (PemWriter writer = new PemWriter(new PrintWriter(System.out))) {
writer.writeObject(pkcs8Generator);
}
This will output an encrypted private key:
-----BEGIN ENCRYPTED PRIVATE KEY-----
MIICrjAoBgoqhkiG9w0BDAEDMBoEFM1kXgdc0vzEhCwQG5G2wAaSA7POAgInEASC
AoAkBPjKkNVpt9O9+Q63WMscX0eEiGyD6/kFwI+ZgH4/s98uKDHxWTB0fQ+HA+Iy
gQC1b+QhT2HVR0DIB6lfhou4FrcJXBAqf4h0ybkfmE4xTfVQcCpgKm4uUC/FYjks
dgTMajN9NHL06nUjd/0uVsM2bzbJHXlDmPRB0LdfvuxzcGN0Vvn13IJrjRnGwTGR
nv6ZyE3gbjCRanINhMtCDMtg9Ydm7+DHC53YOeqbbhgO9/aJHpRzX/H6zLYp/oa0
GpHM6NzsTfABS8QyqR+EaoFad/XHvC9nKUDqm8LVjmKdlXrLDmpHQ4kxZqMIbijE
/Pu2IfHB0jYYa93F2i0fKkIaeve4oo3/izBn0amXVnsPMnkyrIoUUaLzI/gb/419
vp+1kmAKsEFCRIDQlDCiR9CyuePOaR0d7EckVMDU0uR9MXYAV73Y3VRXe1votrQ/
5Wi8ueio9TBDYj9wYYoYmRpz454HqJ/71k0xr5IJugJIJkUzNN9VkjK9rhgT0Vz5
wY/E1yZZepqCR1xrYgDuu/n4t63EERMo+BgkpKBMnWliU3QdQT2r4qBnma+c9lq8
IWb3y3Phl4LsX3DnLed1rUIOcQKiN2T9/yl+7eEtk8APkKuLK5DDDytgAcOQ1MIF
7Ie2939OG1c3mAwrdeOk20zf0SSbpX17MDmUoMwKsP9u8bqHahNoucjtuVSRtjSe
94xntc0fHkiIueApffxjErJOd2pmjGxJ7D2lkjV4G3AEg3vqFXk6E8nPIqIZL4qI
9KzmAFv88+QDIVTM5fheIOxZpeBkXtq2e19gCijiysqLDWL2CLuN4LVzhKCkJF6x
QGN1FcLk95ikvhI/LEn6qrih
-----END ENCRYPTED PRIVATE KEY-----

Convert message and signature to BouncyCastle CMSSignedData object

I have an X509CertificateObject, a matching RSAPublicKey and managed to create a byte array containing a valid digital certificate for some message object also as a byte array.
Unfortunately the system I'm building upon only accepts CMSSignedData objects as input.
How do I convert my basic building blocks into such a valid CMSSignedData object?
Background: I'm experimenting with Java Bouncy Castle RSA blind signatures according to this example (digest is SHA512) and need to feed the result into the standard signature processing.

First, you'll probably want to sign your data with a private key. The idea being that the signature should be something only you can create. One you get that the rest should be as follows:
X509Certificate signingCertificate = getSigningCertificate();
//The chain of certificates that issued your signing certificate and so on
Collection&ltX509Certificate&gt certificateChain = getCertificateChain();
PrivateKey pk = getPrivateKey();
byte[] message = "SomeMessage".getBytes();
CMSSignedDataGenerator generator = new CMSSignedDataGenerator();
certificateChain.add(signingCertificate);
generator.addCertificates(new CollectionStore(certificateChain));
JcaDigestCalculatorProviderBuilder jcaDigestProvider = new JcaDigestCalculatorProviderBuilder();
jcaDigestProvider.setProvider(new BouncyCastleProvider());
JcaSignerInfoGeneratorBuilder singerInfoGenerator = new JcaSignerInfoGeneratorBuilder(jcaDigestProvider.build());
AlgorithmIdentifier sigAlgId = new DefaultSignatureAlgorithmIdentifierFinder().find("SHA1withRSA");
AlgorithmIdentifier digAlgId = new DefaultDigestAlgorithmIdentifierFinder().find(sigAlgId);
AsymmetricKeyParameter privateKeyParam = PrivateKeyFactory.createKey(pk.getEncoded());
ContentSigner cs = new BcRSAContentSignerBuilder(sigAlgId, digAlgId).build(privateKeyParam);
SignerInfoGenerator sig = singerInfoGenerator.build(cs, signingCertificate);
generator.addSignerInfoGenerator(sig);
CMSSignedData data = generator.generate(new CMSProcessableByteArray(message), true);