public DHParameters(
BigInteger p,
BigInteger g,
BigInteger q,
BigInteger j,
DHValidationParameters validation)
: this(p, g, q, DefaultMinimumLength, 0, j, validation)
{
}
public DHParameters(
BigInteger p,
BigInteger g,
BigInteger q,
int m,
int l,
BigInteger j,
DHValidationParameters validation)
{
if (p == null)
throw new ArgumentNullException("p");
if (g == null)
throw new ArgumentNullException("g");
if (!p.TestBit(0))
throw new ArgumentException("field must be an odd prime", "p");
if (g.CompareTo(BigInteger.Two) < 0
|| g.CompareTo(p.Subtract(BigInteger.Two)) > 0)
throw new ArgumentException("generator must in the range [2, p - 2]", "g");
if (q != null && q.BitLength >= p.BitLength)
throw new ArgumentException("q too big to be a factor of (p-1)", "q");
if (m >= p.BitLength)
throw new ArgumentException("m value must be < bitlength of p", "m");
if (l != 0)
{
if (l >= p.BitLength)
throw new ArgumentException("when l value specified, it must be less than bitlength(p)", "l");
if (l < m)
throw new ArgumentException("when l value specified, it may not be less than m value", "l");
}
if (j != null && j.CompareTo(BigInteger.Two) < 0)
throw new ArgumentException("subgroup factor must be >= 2", "j");
// TODO If q, j both provided, validate p = jq + 1 ?
this.p = p;
this.g = g;
this.q = q;
this.m = m;
this.l = l;
this.j = j;
this.validation = validation;
}
protected bool Equals(
DHValidationParameters other)
{
return(counter == other.counter &&
Arrays.AreEqual(this.seed, other.seed));
}
protected bool Equals(
DHValidationParameters other)
{
return counter == other.counter
&& Arrays.AreEqual(this.seed, other.seed);
}
public static AsymmetricKeyParameter CreateKey(
SubjectPublicKeyInfo keyInfo)
{
AlgorithmIdentifier algID = keyInfo.AlgorithmID;
DerObjectIdentifier algOid = algID.ObjectID;
// TODO See RSAUtil.isRsaOid in Java build
if (algOid.Equals(PkcsObjectIdentifiers.RsaEncryption)
|| algOid.Equals(X509ObjectIdentifiers.IdEARsa)
|| algOid.Equals(PkcsObjectIdentifiers.IdRsassaPss)
|| algOid.Equals(PkcsObjectIdentifiers.IdRsaesOaep))
{
RsaPublicKeyStructure pubKey = RsaPublicKeyStructure.GetInstance(
keyInfo.GetPublicKey());
return new RsaKeyParameters(false, pubKey.Modulus, pubKey.PublicExponent);
}
else if (algOid.Equals(X9ObjectIdentifiers.DHPublicNumber))
{
Asn1Sequence seq = Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object());
DHPublicKey dhPublicKey = DHPublicKey.GetInstance(keyInfo.GetPublicKey());
BigInteger y = dhPublicKey.Y.Value;
if (IsPkcsDHParam(seq))
return ReadPkcsDHParam(algOid, y, seq);
DHDomainParameters dhParams = DHDomainParameters.GetInstance(seq);
BigInteger p = dhParams.P.Value;
BigInteger g = dhParams.G.Value;
BigInteger q = dhParams.Q.Value;
BigInteger j = null;
if (dhParams.J != null)
{
j = dhParams.J.Value;
}
DHValidationParameters validation = null;
DHValidationParms dhValidationParms = dhParams.ValidationParms;
if (dhValidationParms != null)
{
byte[] seed = dhValidationParms.Seed.GetBytes();
BigInteger pgenCounter = dhValidationParms.PgenCounter.Value;
// TODO Check pgenCounter size?
validation = new DHValidationParameters(seed, pgenCounter.IntValue);
}
return new DHPublicKeyParameters(y, new DHParameters(p, g, q, j, validation));
}
else if (algOid.Equals(PkcsObjectIdentifiers.DhKeyAgreement))
{
Asn1Sequence seq = Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object());
DerInteger derY = (DerInteger) keyInfo.GetPublicKey();
return ReadPkcsDHParam(algOid, derY.Value, seq);
}
else if (algOid.Equals(OiwObjectIdentifiers.ElGamalAlgorithm))
{
ElGamalParameter para = new ElGamalParameter(
Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object()));
DerInteger derY = (DerInteger) keyInfo.GetPublicKey();
return new ElGamalPublicKeyParameters(
derY.Value,
new ElGamalParameters(para.P, para.G));
}
else if (algOid.Equals(X9ObjectIdentifiers.IdDsa)
|| algOid.Equals(OiwObjectIdentifiers.DsaWithSha1))
{
DerInteger derY = (DerInteger) keyInfo.GetPublicKey();
Asn1Encodable ae = algID.Parameters;
DsaParameters parameters = null;
if (ae != null)
{
DsaParameter para = DsaParameter.GetInstance(ae.ToAsn1Object());
parameters = new DsaParameters(para.P, para.Q, para.G);
}
return new DsaPublicKeyParameters(derY.Value, parameters);
}
else if (algOid.Equals(X9ObjectIdentifiers.IdECPublicKey))
{
X962Parameters para = new X962Parameters(
algID.Parameters.ToAsn1Object());
X9ECParameters ecP;
if (para.IsNamedCurve)
{
ecP = ECKeyPairGenerator.FindECCurveByOid((DerObjectIdentifier)para.Parameters);
}
else
{
ecP = new X9ECParameters((Asn1Sequence)para.Parameters);
}
ECDomainParameters dParams = new ECDomainParameters(
ecP.Curve,
ecP.G,
ecP.N,
ecP.H,
ecP.GetSeed());
DerBitString bits = keyInfo.PublicKeyData;
byte[] data = bits.GetBytes();
Asn1OctetString key = new DerOctetString(data);
X9ECPoint derQ = new X9ECPoint(dParams.Curve, key);
return new ECPublicKeyParameters(derQ.Point, dParams);
}
else if (algOid.Equals(CryptoProObjectIdentifiers.GostR3410x2001))
{
Gost3410PublicKeyAlgParameters gostParams = new Gost3410PublicKeyAlgParameters(
(Asn1Sequence) algID.Parameters);
Asn1OctetString key;
try
{
key = (Asn1OctetString) keyInfo.GetPublicKey();
}
catch (IOException)
{
throw new ArgumentException("invalid info structure in GOST3410 public key");
}
byte[] keyEnc = key.GetOctets();
byte[] x = new byte[32];
byte[] y = new byte[32];
for (int i = 0; i != y.Length; i++)
{
x[i] = keyEnc[32 - 1 - i];
}
for (int i = 0; i != x.Length; i++)
{
y[i] = keyEnc[64 - 1 - i];
}
ECDomainParameters ecP = ECGost3410NamedCurves.GetByOid(gostParams.PublicKeyParamSet);
if (ecP == null)
return null;
ECPoint q = ecP.Curve.CreatePoint(new BigInteger(1, x), new BigInteger(1, y), false);
return new ECPublicKeyParameters("ECGOST3410", q, gostParams.PublicKeyParamSet);
}
else if (algOid.Equals(CryptoProObjectIdentifiers.GostR3410x94))
{
Gost3410PublicKeyAlgParameters algParams = new Gost3410PublicKeyAlgParameters(
(Asn1Sequence) algID.Parameters);
DerOctetString derY;
try
{
derY = (DerOctetString) keyInfo.GetPublicKey();
}
catch (IOException)
{
throw new ArgumentException("invalid info structure in GOST3410 public key");
}
byte[] keyEnc = derY.GetOctets();
byte[] keyBytes = new byte[keyEnc.Length];
for (int i = 0; i != keyEnc.Length; i++)
{
keyBytes[i] = keyEnc[keyEnc.Length - 1 - i]; // was little endian
}
BigInteger y = new BigInteger(1, keyBytes);
return new Gost3410PublicKeyParameters(y, algParams.PublicKeyParamSet);
}
else
{
throw new SecurityUtilityException("algorithm identifier in key not recognised: " + algOid);
}
}
