diff options
Diffstat (limited to 'crypto/src/asn1/x9/X9Curve.cs')
| -rw-r--r-- | crypto/src/asn1/x9/X9Curve.cs | 76 |
1 files changed, 43 insertions, 33 deletions
diff --git a/crypto/src/asn1/x9/X9Curve.cs b/crypto/src/asn1/x9/X9Curve.cs index f05a946c2..eab94def8 100644 --- a/crypto/src/asn1/x9/X9Curve.cs +++ b/crypto/src/asn1/x9/X9Curve.cs @@ -47,9 +47,19 @@ namespace Org.BouncyCastle.Asn1.X9 } } + [Obsolete("Use constructor including order/cofactor")] public X9Curve( X9FieldID fieldID, Asn1Sequence seq) + : this(fieldID, null, null, seq) + { + } + + public X9Curve( + X9FieldID fieldID, + BigInteger order, + BigInteger cofactor, + Asn1Sequence seq) { if (fieldID == null) throw new ArgumentNullException("fieldID"); @@ -60,47 +70,47 @@ namespace Org.BouncyCastle.Asn1.X9 if (fieldIdentifier.Equals(X9ObjectIdentifiers.PrimeField)) { - BigInteger q = ((DerInteger) fieldID.Parameters).Value; - X9FieldElement x9A = new X9FieldElement(q, (Asn1OctetString) seq[0]); - X9FieldElement x9B = new X9FieldElement(q, (Asn1OctetString) seq[1]); - curve = new FpCurve(q, x9A.Value.ToBigInteger(), x9B.Value.ToBigInteger()); + BigInteger p = ((DerInteger)fieldID.Parameters).Value; + BigInteger A = new BigInteger(1, Asn1OctetString.GetInstance(seq[0]).GetOctets()); + BigInteger B = new BigInteger(1, Asn1OctetString.GetInstance(seq[1]).GetOctets()); + curve = new FpCurve(p, A, B, order, cofactor); } - else + else if (fieldIdentifier.Equals(X9ObjectIdentifiers.CharacteristicTwoField)) { - if (fieldIdentifier.Equals(X9ObjectIdentifiers.CharacteristicTwoField)) + // Characteristic two field + DerSequence parameters = (DerSequence)fieldID.Parameters; + int m = ((DerInteger)parameters[0]).Value.IntValue; + DerObjectIdentifier representation + = (DerObjectIdentifier)parameters[1]; + + int k1 = 0; + int k2 = 0; + int k3 = 0; + if (representation.Equals(X9ObjectIdentifiers.TPBasis)) { - // Characteristic two field - DerSequence parameters = (DerSequence)fieldID.Parameters; - int m = ((DerInteger)parameters[0]).Value.IntValue; - DerObjectIdentifier representation - = (DerObjectIdentifier)parameters[1]; - - int k1 = 0; - int k2 = 0; - int k3 = 0; - if (representation.Equals(X9ObjectIdentifiers.TPBasis)) - { - // Trinomial basis representation - k1 = ((DerInteger)parameters[2]).Value.IntValue; - } - else - { - // Pentanomial basis representation - DerSequence pentanomial = (DerSequence) parameters[2]; - k1 = ((DerInteger) pentanomial[0]).Value.IntValue; - k2 = ((DerInteger) pentanomial[1]).Value.IntValue; - k3 = ((DerInteger) pentanomial[2]).Value.IntValue; - } - X9FieldElement x9A = new X9FieldElement(m, k1, k2, k3, (Asn1OctetString)seq[0]); - X9FieldElement x9B = new X9FieldElement(m, k1, k2, k3, (Asn1OctetString)seq[1]); - // TODO Is it possible to get the order (n) and cofactor(h) too? - curve = new F2mCurve(m, k1, k2, k3, x9A.Value.ToBigInteger(), x9B.Value.ToBigInteger()); + // Trinomial basis representation + k1 = ((DerInteger)parameters[2]).Value.IntValue; } + else + { + // Pentanomial basis representation + DerSequence pentanomial = (DerSequence) parameters[2]; + k1 = ((DerInteger) pentanomial[0]).Value.IntValue; + k2 = ((DerInteger) pentanomial[1]).Value.IntValue; + k3 = ((DerInteger) pentanomial[2]).Value.IntValue; + } + BigInteger A = new BigInteger(1, Asn1OctetString.GetInstance(seq[0]).GetOctets()); + BigInteger B = new BigInteger(1, Asn1OctetString.GetInstance(seq[1]).GetOctets()); + curve = new F2mCurve(m, k1, k2, k3, A, B, order, cofactor); + } + else + { + throw new ArgumentException("This type of ECCurve is not implemented"); } if (seq.Count == 3) { - seed = ((DerBitString) seq[2]).GetBytes(); + seed = ((DerBitString)seq[2]).GetBytes(); } } |