NistNamedCurves
Elliptic curve registry for NIST curves.
using Org.BouncyCastle.Asn1.Sec;
using Org.BouncyCastle.Asn1.X9;
using Org.BouncyCastle.Utilities.Collections;
using System;
using System.Collections.Generic;
namespace Org.BouncyCastle.Asn1.Nist
{
public static class NistNamedCurves
{
private static readonly Dictionary<string, DerObjectIdentifier> objIds;
private static readonly Dictionary<DerObjectIdentifier, string> names;
public static IEnumerable<string> Names => CollectionUtilities.Proxy(objIds.Keys);
private static void DefineCurveAlias(string name, DerObjectIdentifier oid)
{
if (SecNamedCurves.GetByOidLazy(oid) == null)
throw new InvalidOperationException();
objIds.Add(name, oid);
names.Add(oid, name);
}
static NistNamedCurves()
{
objIds = new Dictionary<string, DerObjectIdentifier>(StringComparer.OrdinalIgnoreCase);
names = new Dictionary<DerObjectIdentifier, string>();
DefineCurveAlias("B-163", SecObjectIdentifiers.SecT163r2);
DefineCurveAlias("B-233", SecObjectIdentifiers.SecT233r1);
DefineCurveAlias("B-283", SecObjectIdentifiers.SecT283r1);
DefineCurveAlias("B-409", SecObjectIdentifiers.SecT409r1);
DefineCurveAlias("B-571", SecObjectIdentifiers.SecT571r1);
DefineCurveAlias("K-163", SecObjectIdentifiers.SecT163k1);
DefineCurveAlias("K-233", SecObjectIdentifiers.SecT233k1);
DefineCurveAlias("K-283", SecObjectIdentifiers.SecT283k1);
DefineCurveAlias("K-409", SecObjectIdentifiers.SecT409k1);
DefineCurveAlias("K-571", SecObjectIdentifiers.SecT571k1);
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)
{
DerObjectIdentifier oid = GetOid(name);
if (oid != null)
return GetByOid(oid);
return null;
}
public static X9ECParametersHolder GetByNameLazy(string name)
{
DerObjectIdentifier oid = GetOid(name);
if (oid != null)
return GetByOidLazy(oid);
return null;
}
public static X9ECParameters GetByOid(DerObjectIdentifier oid)
{
return GetByOidLazy(oid)?.Parameters;
}
public static X9ECParametersHolder GetByOidLazy(DerObjectIdentifier oid)
{
if (!names.ContainsKey(oid))
return null;
return SecNamedCurves.GetByOidLazy(oid);
}
public static string GetName(DerObjectIdentifier oid)
{
return CollectionUtilities.GetValueOrNull(names, oid);
}
public static DerObjectIdentifier GetOid(string name)
{
return CollectionUtilities.GetValueOrNull(objIds, name);
}
}
}