PublicKeyFactory
using Org.BouncyCastle.Asn1;
using Org.BouncyCastle.Asn1.Cryptlib;
using Org.BouncyCastle.Asn1.CryptoPro;
using Org.BouncyCastle.Asn1.EdEC;
using Org.BouncyCastle.Asn1.Gnu;
using Org.BouncyCastle.Asn1.Oiw;
using Org.BouncyCastle.Asn1.Pkcs;
using Org.BouncyCastle.Asn1.Rosstandart;
using Org.BouncyCastle.Asn1.X509;
using Org.BouncyCastle.Asn1.X9;
using Org.BouncyCastle.Crypto;
using Org.BouncyCastle.Crypto.Generators;
using Org.BouncyCastle.Crypto.Parameters;
using Org.BouncyCastle.Math;
using Org.BouncyCastle.Math.EC;
using System;
using System.IO;
namespace Org.BouncyCastle.Security
{
public static class PublicKeyFactory
{
public static AsymmetricKeyParameter CreateKey(byte[] keyInfoData)
{
return CreateKey(SubjectPublicKeyInfo.GetInstance(Asn1Object.FromByteArray(keyInfoData)));
}
public static AsymmetricKeyParameter CreateKey(Stream inStr)
{
return CreateKey(SubjectPublicKeyInfo.GetInstance(Asn1Object.FromStream(inStr)));
}
public static AsymmetricKeyParameter CreateKey(SubjectPublicKeyInfo keyInfo)
{
AlgorithmIdentifier algorithm = keyInfo.Algorithm;
DerObjectIdentifier algorithm2 = algorithm.Algorithm;
if (algorithm2.Equals(PkcsObjectIdentifiers.RsaEncryption) || algorithm2.Equals(X509ObjectIdentifiers.IdEARsa) || algorithm2.Equals(PkcsObjectIdentifiers.IdRsassaPss) || algorithm2.Equals(PkcsObjectIdentifiers.IdRsaesOaep)) {
RsaPublicKeyStructure instance = RsaPublicKeyStructure.GetInstance(keyInfo.ParsePublicKey());
return new RsaKeyParameters(false, instance.Modulus, instance.PublicExponent);
}
if (algorithm2.Equals(X9ObjectIdentifiers.DHPublicNumber)) {
Asn1Sequence instance2 = Asn1Sequence.GetInstance(algorithm.Parameters.ToAsn1Object());
BigInteger value = DHPublicKey.GetInstance(keyInfo.ParsePublicKey()).Y.Value;
if (IsPkcsDHParam(instance2))
return ReadPkcsDHParam(algorithm2, value, instance2);
DHDomainParameters instance3 = DHDomainParameters.GetInstance(instance2);
BigInteger value2 = instance3.P.Value;
BigInteger value3 = instance3.G.Value;
BigInteger value4 = instance3.Q.Value;
BigInteger j = null;
if (instance3.J != null)
j = instance3.J.Value;
DHValidationParameters validation = null;
DHValidationParms validationParms = instance3.ValidationParms;
if (validationParms != null) {
byte[] bytes = validationParms.Seed.GetBytes();
BigInteger value5 = validationParms.PgenCounter.Value;
validation = new DHValidationParameters(bytes, value5.IntValue);
}
return new DHPublicKeyParameters(value, new DHParameters(value2, value3, value4, j, validation));
}
if (algorithm2.Equals(PkcsObjectIdentifiers.DhKeyAgreement)) {
Asn1Sequence instance4 = Asn1Sequence.GetInstance(algorithm.Parameters.ToAsn1Object());
DerInteger derInteger = (DerInteger)keyInfo.ParsePublicKey();
return ReadPkcsDHParam(algorithm2, derInteger.Value, instance4);
}
if (algorithm2.Equals(OiwObjectIdentifiers.ElGamalAlgorithm)) {
ElGamalParameter elGamalParameter = new ElGamalParameter(Asn1Sequence.GetInstance(algorithm.Parameters.ToAsn1Object()));
return new ElGamalPublicKeyParameters(((DerInteger)keyInfo.ParsePublicKey()).Value, new ElGamalParameters(elGamalParameter.P, elGamalParameter.G));
}
if (algorithm2.Equals(X9ObjectIdentifiers.IdDsa) || algorithm2.Equals(OiwObjectIdentifiers.DsaWithSha1)) {
DerInteger obj = (DerInteger)keyInfo.ParsePublicKey();
Asn1Encodable parameters = algorithm.Parameters;
DsaParameters parameters2 = null;
if (parameters != null) {
DsaParameter instance5 = DsaParameter.GetInstance(parameters.ToAsn1Object());
parameters2 = new DsaParameters(instance5.P, instance5.Q, instance5.G);
}
return new DsaPublicKeyParameters(obj.Value, parameters2);
}
if (algorithm2.Equals(X9ObjectIdentifiers.IdECPublicKey)) {
X962Parameters instance6 = X962Parameters.GetInstance(algorithm.Parameters.ToAsn1Object());
X9ECParameters x9ECParameters = (!instance6.IsNamedCurve) ? new X9ECParameters((Asn1Sequence)instance6.Parameters) : ECKeyPairGenerator.FindECCurveByOid((DerObjectIdentifier)instance6.Parameters);
Asn1OctetString s = new DerOctetString(keyInfo.PublicKey.GetBytes());
ECPoint point = new X9ECPoint(x9ECParameters.Curve, s).Point;
if (instance6.IsNamedCurve)
return new ECPublicKeyParameters("EC", point, (DerObjectIdentifier)instance6.Parameters);
ECDomainParameters parameters3 = new ECDomainParameters(x9ECParameters);
return new ECPublicKeyParameters(point, parameters3);
}
if (algorithm2.Equals(CryptoProObjectIdentifiers.GostR3410x2001)) {
DerObjectIdentifier publicKeyParamSet = Gost3410PublicKeyAlgParameters.GetInstance(algorithm.Parameters).PublicKeyParamSet;
X9ECParameters byOid = ECGost3410NamedCurves.GetByOid(publicKeyParamSet);
if (byOid == null)
return null;
Asn1OctetString asn1OctetString;
try {
asn1OctetString = (Asn1OctetString)keyInfo.ParsePublicKey();
} catch (IOException innerException) {
throw new ArgumentException("error recovering GOST3410_2001 public key", innerException);
}
int num = 32;
int num2 = 2 * num;
byte[] octets = asn1OctetString.GetOctets();
if (octets.Length != num2)
throw new ArgumentException("invalid length for GOST3410_2001 public key");
byte[] array = new byte[1 + num2];
array[0] = 4;
for (int i = 1; i <= num; i++) {
array[i] = octets[num - i];
array[i + num] = octets[num2 - i];
}
ECPoint q = byOid.Curve.DecodePoint(array);
return new ECPublicKeyParameters("ECGOST3410", q, publicKeyParamSet);
}
if (algorithm2.Equals(CryptoProObjectIdentifiers.GostR3410x94)) {
Gost3410PublicKeyAlgParameters instance7 = Gost3410PublicKeyAlgParameters.GetInstance(algorithm.Parameters);
Asn1OctetString asn1OctetString2;
try {
asn1OctetString2 = (Asn1OctetString)keyInfo.ParsePublicKey();
} catch (IOException innerException2) {
throw new ArgumentException("error recovering GOST3410_94 public key", innerException2);
}
byte[] octets2 = asn1OctetString2.GetOctets();
return new Gost3410PublicKeyParameters(new BigInteger(1, octets2, false), instance7.PublicKeyParamSet);
}
if (algorithm2.Equals(EdECObjectIdentifiers.id_X25519) || algorithm2.Equals(CryptlibObjectIdentifiers.curvey25519))
return new X25519PublicKeyParameters(GetRawKey(keyInfo));
if (algorithm2.Equals(EdECObjectIdentifiers.id_X448))
return new X448PublicKeyParameters(GetRawKey(keyInfo));
if (algorithm2.Equals(EdECObjectIdentifiers.id_Ed25519) || algorithm2.Equals(GnuObjectIdentifiers.Ed25519))
return new Ed25519PublicKeyParameters(GetRawKey(keyInfo));
if (algorithm2.Equals(EdECObjectIdentifiers.id_Ed448))
return new Ed448PublicKeyParameters(GetRawKey(keyInfo));
if (algorithm2.Equals(RosstandartObjectIdentifiers.id_tc26_gost_3410_12_256) || algorithm2.Equals(RosstandartObjectIdentifiers.id_tc26_gost_3410_12_512) || algorithm2.Equals(RosstandartObjectIdentifiers.id_tc26_agreement_gost_3410_12_256) || algorithm2.Equals(RosstandartObjectIdentifiers.id_tc26_agreement_gost_3410_12_512)) {
Gost3410PublicKeyAlgParameters instance8 = Gost3410PublicKeyAlgParameters.GetInstance(algorithm.Parameters);
DerObjectIdentifier publicKeyParamSet2 = instance8.PublicKeyParamSet;
ECGost3410Parameters eCGost3410Parameters = new ECGost3410Parameters(new ECNamedDomainParameters(publicKeyParamSet2, ECGost3410NamedCurves.GetByOid(publicKeyParamSet2)), publicKeyParamSet2, instance8.DigestParamSet, instance8.EncryptionParamSet);
Asn1OctetString asn1OctetString3;
try {
asn1OctetString3 = (Asn1OctetString)keyInfo.ParsePublicKey();
} catch (IOException innerException3) {
throw new ArgumentException("error recovering GOST3410_2012 public key", innerException3);
}
int num3 = 32;
if (algorithm2.Equals(RosstandartObjectIdentifiers.id_tc26_gost_3410_12_512))
num3 = 64;
int num4 = 2 * num3;
byte[] octets3 = asn1OctetString3.GetOctets();
if (octets3.Length != num4)
throw new ArgumentException("invalid length for GOST3410_2012 public key");
byte[] array2 = new byte[1 + num4];
array2[0] = 4;
for (int k = 1; k <= num3; k++) {
array2[k] = octets3[num3 - k];
array2[k + num3] = octets3[num4 - k];
}
return new ECPublicKeyParameters(eCGost3410Parameters.Curve.DecodePoint(array2), eCGost3410Parameters);
}
throw new SecurityUtilityException("algorithm identifier in public key not recognised: " + algorithm2?.ToString());
}
private static byte[] GetRawKey(SubjectPublicKeyInfo keyInfo)
{
return keyInfo.PublicKey.GetOctets();
}
private static bool IsPkcsDHParam(Asn1Sequence seq)
{
if (seq.Count == 2)
return true;
if (seq.Count > 3)
return false;
DerInteger instance = DerInteger.GetInstance(seq[2]);
DerInteger instance2 = DerInteger.GetInstance(seq[0]);
return instance.Value.CompareTo(BigInteger.ValueOf(instance2.Value.BitLength)) <= 0;
}
private static DHPublicKeyParameters ReadPkcsDHParam(DerObjectIdentifier algOid, BigInteger y, Asn1Sequence seq)
{
DHParameter dHParameter = new DHParameter(seq);
int l = dHParameter.L?.IntValue ?? 0;
DHParameters parameters = new DHParameters(dHParameter.P, dHParameter.G, null, l);
return new DHPublicKeyParameters(y, parameters, algOid);
}
}
}