internal RecipientInfo ToRecipientInfo(
KeyParameter key,
SecureRandom random)
{
byte[] keyBytes = key.GetKey();
if (pubKey != null)
{
IWrapper keyWrapper = Helper.CreateWrapper(keyEncAlg.ObjectID.Id);
keyWrapper.Init(true, new ParametersWithRandom(pubKey, random));
Asn1OctetString encKey = new DerOctetString(
keyWrapper.Wrap(keyBytes, 0, keyBytes.Length));
RecipientIdentifier recipId;
if (cert != null)
{
TbsCertificateStructure tbs = TbsCertificateStructure.GetInstance(
Asn1Object.FromByteArray(cert.GetTbsCertificate()));
Asn1.Cms.IssuerAndSerialNumber encSid = new Asn1.Cms.IssuerAndSerialNumber(
tbs.Issuer, tbs.SerialNumber.Value);
recipId = new RecipientIdentifier(encSid);
}
else
{
recipId = new RecipientIdentifier(subKeyId);
}
return new RecipientInfo(new KeyTransRecipientInfo(recipId, keyEncAlg, encKey));
}
else if (originator != null)
{
IWrapper keyWrapper = Helper.CreateWrapper(
DerObjectIdentifier.GetInstance(
Asn1Sequence.GetInstance(keyEncAlg.Parameters)[0]).Id);
keyWrapper.Init(true, new ParametersWithRandom(secKey, random));
Asn1OctetString encKey = new DerOctetString(
keyWrapper.Wrap(keyBytes, 0, keyBytes.Length));
RecipientEncryptedKey rKey = new RecipientEncryptedKey(
new KeyAgreeRecipientIdentifier(
new Asn1.Cms.IssuerAndSerialNumber(
PrincipalUtilities.GetIssuerX509Principal(cert),
cert.SerialNumber)),
encKey);
return new RecipientInfo(
new KeyAgreeRecipientInfo(originator, ukm, keyEncAlg, new DerSequence(rKey)));
}
else if (derivationAlg != null)
{
string rfc3211WrapperName = Helper.GetRfc3211WrapperName(secKeyAlgorithm);
IWrapper keyWrapper = Helper.CreateWrapper(rfc3211WrapperName);
// Note: In Java build, the IV is automatically generated in JCE layer
int ivLength = rfc3211WrapperName.StartsWith("DESEDE") ? 8 : 16;
byte[] iv = new byte[ivLength];
random.NextBytes(iv);
ICipherParameters parameters = new ParametersWithIV(secKey, iv);
keyWrapper.Init(true, new ParametersWithRandom(parameters, random));
Asn1OctetString encKey = new DerOctetString(
keyWrapper.Wrap(keyBytes, 0, keyBytes.Length));
// byte[] iv = keyWrapper.GetIV();
DerSequence seq = new DerSequence(
new DerObjectIdentifier(secKeyAlgorithm),
new DerOctetString(iv));
keyEncAlg = new AlgorithmIdentifier(PkcsObjectIdentifiers.IdAlgPwriKek, seq);
return new RecipientInfo(new PasswordRecipientInfo(derivationAlg, keyEncAlg, encKey));
}
else
{
IWrapper keyWrapper = Helper.CreateWrapper(keyEncAlg.ObjectID.Id);
keyWrapper.Init(true, new ParametersWithRandom(secKey, random));
Asn1OctetString encKey = new DerOctetString(
keyWrapper.Wrap(keyBytes, 0, keyBytes.Length));
return new RecipientInfo(new KekRecipientInfo(secKeyId, keyEncAlg, encKey));
}
}
public static RecipientEncryptedKey GetInstance(Asn1TaggedObject obj, bool isExplicit)
{
return(RecipientEncryptedKey.GetInstance(Asn1Sequence.GetInstance(obj, isExplicit)));
}