path: root/crypto/src/crypto/ec/CustomNamedCurves.cs

using System;
using System.Collections;

using Org.BouncyCastle.Asn1;
using Org.BouncyCastle.Asn1.Sec;
using Org.BouncyCastle.Asn1.X9;
using Org.BouncyCastle.Math;
using Org.BouncyCastle.Math.EC;
using Org.BouncyCastle.Math.EC.Custom.Djb;
using Org.BouncyCastle.Math.EC.Custom.Sec;
using Org.BouncyCastle.Math.EC.Endo;
using Org.BouncyCastle.Utilities;
using Org.BouncyCastle.Utilities.Collections;
using Org.BouncyCastle.Utilities.Encoders;

namespace Org.BouncyCastle.Crypto.EC
{
    public sealed class CustomNamedCurves
    {
        private CustomNamedCurves()
        {
        }

        private static BigInteger FromHex(string hex)
        {
            return new BigInteger(1, Hex.Decode(hex));
        }

        private static ECCurve ConfigureCurve(ECCurve curve)
        {
            return curve;
        }

        private static ECCurve ConfigureCurveGlv(ECCurve c, GlvTypeBParameters p)
        {
            return c.Configure().SetEndomorphism(new GlvTypeBEndomorphism(c, p)).Create();
        }

        /*
         * curve25519
         */
        internal class Curve25519Holder
            : X9ECParametersHolder
        {
            private Curve25519Holder() { }

            internal static readonly X9ECParametersHolder Instance = new Curve25519Holder();

            protected override X9ECParameters CreateParameters()
            {
                byte[] S = null;
                ECCurve curve = ConfigureCurve(new Curve25519());

                /*
                 * NOTE: Curve25519 was specified in Montgomery form. Rewriting in Weierstrass form
                 * involves substitution of variables, so the base-point x coordinate is 9 + (486662 / 3).
                 * 
                 * The Curve25519 paper doesn't say which of the two possible y values the base
                 * point has. The choice here is guided by language in the Ed25519 paper.
                 * 
                 * (The other possible y value is 5F51E65E475F794B1FE122D388B72EB36DC2B28192839E4DD6163A5D81312C14) 
                 */
                ECPoint G = curve.DecodePoint(Hex.Decode("04"
                    + "2AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAD245A"
                    + "20AE19A1B8A086B4E01EDD2C7748D14C923D4D7E6D7C61B229E9C5A27ECED3D9"));

                return new X9ECParameters(curve, G, curve.Order, curve.Cofactor, S);
            }
        }

        /*
         * secp192k1
         */
        internal class Secp192k1Holder
            : X9ECParametersHolder
        {
            private Secp192k1Holder() { }

            internal static readonly X9ECParametersHolder Instance = new Secp192k1Holder();

            protected override X9ECParameters CreateParameters()
            {
                byte[] S = null;
                GlvTypeBParameters glv = new GlvTypeBParameters(
                    new BigInteger("bb85691939b869c1d087f601554b96b80cb4f55b35f433c2", 16),
                    new BigInteger("3d84f26c12238d7b4f3d516613c1759033b1a5800175d0b1", 16),
                    new BigInteger[]{
                        new BigInteger("71169be7330b3038edb025f1", 16),
                        new BigInteger("-b3fb3400dec5c4adceb8655c", 16) },
                    new BigInteger[]{
                        new BigInteger("12511cfe811d0f4e6bc688b4d", 16),
                        new BigInteger("71169be7330b3038edb025f1", 16) },
                    new BigInteger("71169be7330b3038edb025f1d0f9", 16),
                    new BigInteger("b3fb3400dec5c4adceb8655d4c94", 16),
                    208);
                ECCurve curve = ConfigureCurveGlv(new SecP192K1Curve(), glv);
                ECPoint G = curve.DecodePoint(Hex.Decode("04"
                    + "DB4FF10EC057E9AE26B07D0280B7F4341DA5D1B1EAE06C7D"
                    + "9B2F2F6D9C5628A7844163D015BE86344082AA88D95E2F9D"));
                return new X9ECParameters(curve, G, curve.Order, curve.Cofactor, S);
            }
        }

        /*
         * secp192r1
         */
        internal class Secp192r1Holder
            : X9ECParametersHolder
        {
            private Secp192r1Holder() { }

            internal static readonly X9ECParametersHolder Instance = new Secp192r1Holder();

            protected override X9ECParameters CreateParameters()
            {
                byte[] S = Hex.Decode("3045AE6FC8422F64ED579528D38120EAE12196D5");
                ECCurve curve = ConfigureCurve(new SecP192R1Curve());
                ECPoint G = curve.DecodePoint(Hex.Decode("04"
                    + "188DA80EB03090F67CBF20EB43A18800F4FF0AFD82FF1012"
                    + "07192B95FFC8DA78631011ED6B24CDD573F977A11E794811"));
                return new X9ECParameters(curve, G, curve.Order, curve.Cofactor, S);
            }
        }

        /*
         * secp224k1
         */
        internal class Secp224k1Holder
            : X9ECParametersHolder
        {
            private Secp224k1Holder() { }

            internal static readonly X9ECParametersHolder Instance = new Secp224k1Holder();

            protected override X9ECParameters CreateParameters()
            {
                byte[] S = null;
                GlvTypeBParameters glv = new GlvTypeBParameters(
                    new BigInteger("fe0e87005b4e83761908c5131d552a850b3f58b749c37cf5b84d6768", 16),
                    new BigInteger("60dcd2104c4cbc0be6eeefc2bdd610739ec34e317f9b33046c9e4788", 16),
                    new BigInteger[]{
                        new BigInteger("6b8cf07d4ca75c88957d9d670591", 16),
                        new BigInteger("-b8adf1378a6eb73409fa6c9c637d", 16) },
                    new BigInteger[]{
                        new BigInteger("1243ae1b4d71613bc9f780a03690e", 16),
                        new BigInteger("6b8cf07d4ca75c88957d9d670591", 16) },
                    new BigInteger("6b8cf07d4ca75c88957d9d67059037a4", 16),
                    new BigInteger("b8adf1378a6eb73409fa6c9c637ba7f5", 16),
                    240);
                ECCurve curve = ConfigureCurveGlv(new SecP224K1Curve(), glv);
                ECPoint G = curve.DecodePoint(Hex.Decode("04"
                    + "A1455B334DF099DF30FC28A169A467E9E47075A90F7E650EB6B7A45C"
                    + "7E089FED7FBA344282CAFBD6F7E319F7C0B0BD59E2CA4BDB556D61A5"));
                return new X9ECParameters(curve, G, curve.Order, curve.Cofactor, S);
            }
        }

        /*
         * secp224r1
         */
        internal class Secp224r1Holder
            : X9ECParametersHolder
        {
            private Secp224r1Holder() { }

            internal static readonly X9ECParametersHolder Instance = new Secp224r1Holder();

            protected override X9ECParameters CreateParameters()
            {
                byte[] S = Hex.Decode("BD71344799D5C7FCDC45B59FA3B9AB8F6A948BC5");
                ECCurve curve = ConfigureCurve(new SecP224R1Curve());
                ECPoint G = curve.DecodePoint(Hex.Decode("04"
                    + "B70E0CBD6BB4BF7F321390B94A03C1D356C21122343280D6115C1D21"
                    + "BD376388B5F723FB4C22DFE6CD4375A05A07476444D5819985007E34"));
                return new X9ECParameters(curve, G, curve.Order, curve.Cofactor, S);
            }
        }

        /*
         * secp256k1
         */
        internal class Secp256k1Holder
            : X9ECParametersHolder
        {
            private Secp256k1Holder() {}

            internal static readonly X9ECParametersHolder Instance = new Secp256k1Holder();

            protected override X9ECParameters CreateParameters()
            {
                byte[] S = null;
                GlvTypeBParameters glv = new GlvTypeBParameters(
                    new BigInteger("7ae96a2b657c07106e64479eac3434e99cf0497512f58995c1396c28719501ee", 16),
                    new BigInteger("5363ad4cc05c30e0a5261c028812645a122e22ea20816678df02967c1b23bd72", 16),
                    new BigInteger[]{
                        new BigInteger("3086d221a7d46bcde86c90e49284eb15", 16),
                        new BigInteger("-e4437ed6010e88286f547fa90abfe4c3", 16) },
                    new BigInteger[]{
                        new BigInteger("114ca50f7a8e2f3f657c1108d9d44cfd8", 16),
                        new BigInteger("3086d221a7d46bcde86c90e49284eb15", 16) },
                    new BigInteger("3086d221a7d46bcde86c90e49284eb153dab", 16),
                    new BigInteger("e4437ed6010e88286f547fa90abfe4c42212", 16),
                    272);
                ECCurve curve = ConfigureCurveGlv(new SecP256K1Curve(), glv);
                ECPoint G = curve.DecodePoint(Hex.Decode("04"
                    + "79BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798"
                    + "483ADA7726A3C4655DA4FBFC0E1108A8FD17B448A68554199C47D08FFB10D4B8"));
                return new X9ECParameters(curve, G, curve.Order, curve.Cofactor, S);
            }
        }

        /*
         * secp256r1
         */
        internal class Secp256r1Holder
            : X9ECParametersHolder
        {
            private Secp256r1Holder() {}

            internal static readonly X9ECParametersHolder Instance = new Secp256r1Holder();

            protected override X9ECParameters CreateParameters()
            {
                byte[] S = Hex.Decode("C49D360886E704936A6678E1139D26B7819F7E90");
                ECCurve curve = ConfigureCurve(new SecP256R1Curve());
                ECPoint G = curve.DecodePoint(Hex.Decode("04"
                    + "6B17D1F2E12C4247F8BCE6E563A440F277037D812DEB33A0F4A13945D898C296"
                    + "4FE342E2FE1A7F9B8EE7EB4A7C0F9E162BCE33576B315ECECBB6406837BF51F5"));
                return new X9ECParameters(curve, G, curve.Order, curve.Cofactor, S);
            }
        }

        /*
         * secp384r1
         */
        internal class Secp384r1Holder
            : X9ECParametersHolder
        {
            private Secp384r1Holder() { }

            internal static readonly X9ECParametersHolder Instance = new Secp384r1Holder();

            protected override X9ECParameters CreateParameters()
            {
                byte[] S = Hex.Decode("A335926AA319A27A1D00896A6773A4827ACDAC73");
                ECCurve curve = ConfigureCurve(new SecP384R1Curve());
                ECPoint G = curve.DecodePoint(Hex.Decode("04"
                    + "AA87CA22BE8B05378EB1C71EF320AD746E1D3B628BA79B9859F741E082542A385502F25DBF55296C3A545E3872760AB7"
                    + "3617DE4A96262C6F5D9E98BF9292DC29F8F41DBD289A147CE9DA3113B5F0B8C00A60B1CE1D7E819D7A431D7C90EA0E5F"));
                return new X9ECParameters(curve, G, curve.Order, curve.Cofactor, S);
            }
        }

        /*
         * secp521r1
         */
        internal class Secp521r1Holder
            : X9ECParametersHolder
        {
            private Secp521r1Holder() { }

            internal static readonly X9ECParametersHolder Instance = new Secp521r1Holder();

            protected override X9ECParameters CreateParameters()
            {
                byte[] S = Hex.Decode("D09E8800291CB85396CC6717393284AAA0DA64BA");
                ECCurve curve = ConfigureCurve(new SecP521R1Curve());
                ECPoint G = curve.DecodePoint(Hex.Decode("04"
                    + "00C6858E06B70404E9CD9E3ECB662395B4429C648139053FB521F828AF606B4D3DBAA14B5E77EFE75928FE1DC127A2FFA8DE3348B3C1856A429BF97E7E31C2E5BD66"
                    + "011839296A789A3BC0045C8A5FB42C7D1BD998F54449579B446817AFBD17273E662C97EE72995EF42640C550B9013FAD0761353C7086A272C24088BE94769FD16650"));
                return new X9ECParameters(curve, G, curve.Order, curve.Cofactor, S);
            }
        }


        private static readonly IDictionary nameToCurve = Platform.CreateHashtable();
        private static readonly IDictionary nameToOid = Platform.CreateHashtable();
        private static readonly IDictionary oidToCurve = Platform.CreateHashtable();
        private static readonly IDictionary oidToName = Platform.CreateHashtable();
        private static readonly IList names = Platform.CreateArrayList();

        private static void DefineCurve(string name, X9ECParametersHolder holder)
        {
            names.Add(name);
            name = Platform.ToLowerInvariant(name);
            nameToCurve.Add(name, holder);
        }

        private static void DefineCurveWithOid(string name, DerObjectIdentifier oid, X9ECParametersHolder holder)
        {
            names.Add(name);
            oidToName.Add(oid, name);
            oidToCurve.Add(oid, holder);
            name = Platform.ToLowerInvariant(name);
            nameToOid.Add(name, oid);
            nameToCurve.Add(name, holder);
        }

        private static void DefineCurveAlias(string name, DerObjectIdentifier oid)
        {
            object curve = oidToCurve[oid];
            if (curve == null)
                throw new InvalidOperationException();

            name = Platform.ToLowerInvariant(name);
            nameToOid.Add(name, oid);
            nameToCurve.Add(name, curve);
        }

        static CustomNamedCurves()
        {
            DefineCurve("curve25519", Curve25519Holder.Instance);

            DefineCurveWithOid("secp192k1", SecObjectIdentifiers.SecP192k1, Secp192k1Holder.Instance);
            DefineCurveWithOid("secp192r1", SecObjectIdentifiers.SecP192r1, Secp192r1Holder.Instance);
            DefineCurveWithOid("secp224k1", SecObjectIdentifiers.SecP224k1, Secp224k1Holder.Instance);
            DefineCurveWithOid("secp224r1", SecObjectIdentifiers.SecP224r1, Secp224r1Holder.Instance);
            DefineCurveWithOid("secp256k1", SecObjectIdentifiers.SecP256k1, Secp256k1Holder.Instance);
            DefineCurveWithOid("secp256r1", SecObjectIdentifiers.SecP256r1, Secp256r1Holder.Instance);
            DefineCurveWithOid("secp384r1", SecObjectIdentifiers.SecP384r1, Secp384r1Holder.Instance);
            DefineCurveWithOid("secp521r1", SecObjectIdentifiers.SecP521r1, Secp521r1Holder.Instance);

            DefineCurveAlias("P-192", SecObjectIdentifiers.SecP192r1);
            DefineCurveAlias("P-224", SecObjectIdentifiers.SecP224r1);
            DefineCurveAlias("P-256", SecObjectIdentifiers.SecP256r1);
            DefineCurveAlias("P-384", SecObjectIdentifiers.SecP384r1);
            DefineCurveAlias("P-521", SecObjectIdentifiers.SecP521r1);
        }

        public static X9ECParameters GetByName(string name)
        {
            X9ECParametersHolder holder = (X9ECParametersHolder)nameToCurve[Platform.ToLowerInvariant(name)];
            return holder == null ? null : holder.Parameters;
        }

        /**
         * return the X9ECParameters object for the named curve represented by
         * the passed in object identifier. Null if the curve isn't present.
         *
         * @param oid an object identifier representing a named curve, if present.
         */
        public static X9ECParameters GetByOid(DerObjectIdentifier oid)
        {
            X9ECParametersHolder holder = (X9ECParametersHolder)oidToCurve[oid];
            return holder == null ? null : holder.Parameters;
        }

        /**
         * return the object identifier signified by the passed in name. Null
         * if there is no object identifier associated with name.
         *
         * @return the object identifier associated with name, if present.
         */
        public static DerObjectIdentifier GetOid(string name)
        {
            return (DerObjectIdentifier)nameToOid[Platform.ToLowerInvariant(name)];
        }

        /**
         * return the named curve name represented by the given object identifier.
         */
        public static string GetName(DerObjectIdentifier oid)
        {
            return (string)oidToName[oid];
        }

        /**
         * returns an enumeration containing the name strings for curves
         * contained in this structure.
         */
        public static IEnumerable Names
        {
            get { return new EnumerableProxy(names); }
        }
    }
}