SshNamedCurves
using Org.BouncyCastle.Asn1;
using Org.BouncyCastle.Asn1.Sec;
using Org.BouncyCastle.Asn1.X9;
using Org.BouncyCastle.Crypto.EC;
using Org.BouncyCastle.Utilities.Collections;
using System;
using System.Collections.Generic;
namespace Org.BouncyCastle.Crypto.Utilities
{
public static class SshNamedCurves
{
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 (FindByOidLazy(oid) == null)
throw new InvalidOperationException();
objIds.Add(name, oid);
names.Add(oid, name);
}
private static X9ECParametersHolder FindByOidLazy(DerObjectIdentifier oid)
{
return ECUtilities.FindECCurveByOidLazy(oid);
}
static SshNamedCurves()
{
objIds = new Dictionary<string, DerObjectIdentifier>(StringComparer.OrdinalIgnoreCase);
names = new Dictionary<DerObjectIdentifier, string>();
DefineCurveAlias("nistp192", SecObjectIdentifiers.SecP192r1);
DefineCurveAlias("nistp224", SecObjectIdentifiers.SecP224r1);
DefineCurveAlias("nistp256", SecObjectIdentifiers.SecP256r1);
DefineCurveAlias("nistp384", SecObjectIdentifiers.SecP384r1);
DefineCurveAlias("nistp521", SecObjectIdentifiers.SecP521r1);
DefineCurveAlias("nistb233", SecObjectIdentifiers.SecT233r1);
DefineCurveAlias("nistb409", SecObjectIdentifiers.SecT409r1);
DefineCurveAlias("nistk163", SecObjectIdentifiers.SecT163k1);
DefineCurveAlias("nistk233", SecObjectIdentifiers.SecT233k1);
DefineCurveAlias("nistk283", SecObjectIdentifiers.SecT283k1);
DefineCurveAlias("nistk409", SecObjectIdentifiers.SecT409k1);
DefineCurveAlias("nistt571", SecObjectIdentifiers.SecT571k1);
}
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 FindByOidLazy(oid);
}
public static string GetName(DerObjectIdentifier oid)
{
return CollectionUtilities.GetValueOrNull(names, oid);
}
public static DerObjectIdentifier GetOid(string name)
{
return CollectionUtilities.GetValueOrNull(objIds, name);
}
}
}