part #2

src/__Libraries/StellaOps.Cryptography.Kms/KmsCryptoProvider.Curves.cs

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+using Microsoft.IdentityModel.Tokens;
+using System.Security.Cryptography;
+
+namespace StellaOps.Cryptography.Kms;
+
+public sealed partial class KmsCryptoProvider
+{
+    private static string ResolveCurveName(ECCurve curve)
+    {
+        if (!string.IsNullOrWhiteSpace(curve.Oid.FriendlyName))
+        {
+            return curve.Oid.FriendlyName switch
+            {
+                "nistP256" => JsonWebKeyECTypes.P256,
+                "nistP384" => JsonWebKeyECTypes.P384,
+                "nistP521" => JsonWebKeyECTypes.P521,
+                _ => JsonWebKeyECTypes.P256
+            };
+        }
+
+        return JsonWebKeyECTypes.P256;
+    }
+
+    private static string ResolveCurveName(int coordinateLength)
+        => coordinateLength switch
+        {
+            32 => JsonWebKeyECTypes.P256,
+            48 => JsonWebKeyECTypes.P384,
+            66 => JsonWebKeyECTypes.P521,
+            _ => JsonWebKeyECTypes.P256
+        };
+
+    private static ECCurve ResolveCurve(string curve)
+        => curve switch
+        {
+            JsonWebKeyECTypes.P256 or "P-256" => ECCurve.NamedCurves.nistP256,
+            JsonWebKeyECTypes.P384 or "P-384" => ECCurve.NamedCurves.nistP384,
+            JsonWebKeyECTypes.P521 or "P-521" => ECCurve.NamedCurves.nistP521,
+            _ => ECCurve.NamedCurves.nistP256
+        };
+}