Support ecdsa-sha2-nistp521, ecdsa-sha2-nistp384 server keys.

README.md

@@ -389,6 +389,8 @@ Supported client key algorithms:
 - rsa-sha2-256
 
 Supported server key algorithms:
+- ecdsa-sha2-nistp521
+- ecdsa-sha2-nistp384
 - ecdsa-sha2-nistp256
 - rsa-sha2-512
 - rsa-sha2-256

src/Tmds.Ssh/AlgorithmNames.cs

@@ -29,6 +29,10 @@ static class AlgorithmNames // TODO: rename to KnownNames
     public static Name RsaSshSha2_512 => new Name(RsaSshSha2_512Bytes);
     private static readonly byte[] EcdsaSha2Nistp256Bytes = "ecdsa-sha2-nistp256"u8.ToArray();
     public static Name EcdsaSha2Nistp256 => new Name(EcdsaSha2Nistp256Bytes);
+    private static readonly byte[] EcdsaSha2Nistp384Bytes = "ecdsa-sha2-nistp384"u8.ToArray();
+    public static Name EcdsaSha2Nistp384 => new Name(EcdsaSha2Nistp384Bytes);
+    private static readonly byte[] EcdsaSha2Nistp521Bytes = "ecdsa-sha2-nistp521"u8.ToArray();
+    public static Name EcdsaSha2Nistp521 => new Name(EcdsaSha2Nistp521Bytes);
 
     // Encryption algorithms.
     private static readonly byte[] Aes128GcmBytes = "[email protected]"u8.ToArray();
@@ -43,6 +47,10 @@ static class AlgorithmNames // TODO: rename to KnownNames
     // Curve names.
     private static readonly byte[] Nistp265Bytes = "nistp256"u8.ToArray();
     public static Name Nistp265 => new Name(Nistp265Bytes);
+    private static readonly byte[] Nistp384Bytes = "nistp384"u8.ToArray();
+    public static Name Nistp384 => new Name(Nistp384Bytes);
+    private static readonly byte[] Nistp521Bytes = "nistp521"u8.ToArray();
+    public static Name Nistp521 => new Name(Nistp521Bytes);
 
     // These fields are initialized in order, so these list must be created after the names.
     // Algorithms are in **order of preference**.

src/Tmds.Ssh/ECDsaPublicKey.cs

@@ -36,6 +36,20 @@ public static ECDsaPublicKey CreateFromSshKey(byte[] key)
             reader.ReadEnd();
             return new ECDsaPublicKey(AlgorithmNames.EcdsaSha2Nistp256, ECCurve.NamedCurves.nistP256, q, HashAlgorithmName.SHA256);
         }
+        else if (name == AlgorithmNames.EcdsaSha2Nistp384)
+        {
+            reader.ReadName(AlgorithmNames.Nistp384);
+            ECPoint q = reader.ReadStringAsECPoint();
+            reader.ReadEnd();
+            return new ECDsaPublicKey(AlgorithmNames.EcdsaSha2Nistp384, ECCurve.NamedCurves.nistP384, q, HashAlgorithmName.SHA384);
+        }
+        else if (name == AlgorithmNames.EcdsaSha2Nistp521)
+        {
+            reader.ReadName(AlgorithmNames.Nistp521);
+            ECPoint q = reader.ReadStringAsECPoint();
+            reader.ReadEnd();
+            return new ECDsaPublicKey(AlgorithmNames.EcdsaSha2Nistp521, ECCurve.NamedCurves.nistP521, q, HashAlgorithmName.SHA512);
+        }
         ThrowHelper.ThrowProtocolUnexpectedValue();
         return null!;
     }

src/Tmds.Ssh/ManagedSshClientSettings.cs

@@ -28,7 +28,7 @@ internal ManagedSshClientSettings()
     // Internal.
     // Algorithms are in **order of preference**.
     internal List<Name> KeyExchangeAlgorithms { get; } = new List<Name>() { AlgorithmNames.EcdhSha2Nistp256, AlgorithmNames.EcdhSha2Nistp384, AlgorithmNames.EcdhSha2Nistp521 };
-    internal List<Name> ServerHostKeyAlgorithms { get; } = new List<Name>() { AlgorithmNames.EcdsaSha2Nistp256, AlgorithmNames.RsaSshSha2_512, AlgorithmNames.RsaSshSha2_256 };
+    internal List<Name> ServerHostKeyAlgorithms { get; } = new List<Name>() { AlgorithmNames.EcdsaSha2Nistp521, AlgorithmNames.EcdsaSha2Nistp384, AlgorithmNames.EcdsaSha2Nistp256, AlgorithmNames.RsaSshSha2_512, AlgorithmNames.RsaSshSha2_256 };
     internal List<Name> EncryptionAlgorithmsClientToServer { get; } = new List<Name>() { AlgorithmNames.Aes256Gcm, AlgorithmNames.Aes128Gcm };
     internal List<Name> EncryptionAlgorithmsServerToClient { get; } = new List<Name>() { AlgorithmNames.Aes256Gcm, AlgorithmNames.Aes128Gcm };
     internal List<Name> MacAlgorithmsClientToServer { get; } = new List<Name>() { AlgorithmNames.HMacSha2_256 };

src/Tmds.Ssh/PublicKey.cs

@@ -12,7 +12,9 @@ abstract class PublicKey
     public static PublicKey CreateFromSshKey(HostKey key)
     {
         Name name = new Name(key.Type);
-        if (name == AlgorithmNames.EcdsaSha2Nistp256)
+        if (name == AlgorithmNames.EcdsaSha2Nistp256 ||
+            name == AlgorithmNames.EcdsaSha2Nistp384 ||
+            name == AlgorithmNames.EcdsaSha2Nistp521)
         {
             return ECDsaPublicKey.CreateFromSshKey(key.RawKey);
         }