Add: SignClient Vsock support

src/Plugins/SignClient/Settings.cs

@@ -18,22 +18,39 @@ public class Settings : PluginSettings
         public const string SectionName = "PluginConfiguration";
         private const string DefaultEndpoint = "http://127.0.0.1:9991";
 
+        internal const string EndpointTcp = "tcp";
+        internal const string EndpointVsock = "vsock";
+
         /// <summary>
         /// The name of the sign client(i.e. Signer).
         /// </summary>
         public readonly string Name;
 
+        /// <summary>
+        /// The type of the endpoint. Default is "tcp", and "tcp" and "vsock" are supported now.
+        /// If the type is "vsock", the "Endpoint" should be "http://contextId:port" or "https://contextId:port".
+        /// </summary>
+        public readonly string EndpointType;
+
         /// <summary>
         /// The host of the sign client(i.e. Signer).
         /// </summary>
         public readonly string Endpoint;
 
+        /// <summary>
+        /// Create a new settings instance from the configuration section.
+        /// </summary>
+        /// <param name="section">The configuration section.</param>
+        /// <exception cref="FormatException">If the endpoint type or endpoint is invalid.</exception>
         public Settings(IConfigurationSection section) : base(section)
         {
             Name = section.GetValue("Name", "SignClient");
+            EndpointType = section.GetValue("EndpointType", EndpointTcp);
+            if (EndpointType != EndpointTcp && EndpointType != EndpointVsock)
+                throw new FormatException($"Invalid endpoint type: {EndpointType}");
 
-            // Only support local host at present, so host always is "127.0.0.1" or "::1" now.
-            Endpoint = section.GetValue("Endpoint", DefaultEndpoint);
+            Endpoint = section.GetValue("Endpoint", DefaultEndpoint); // Only support local host at present
+            _ = GetVsockAddress(); // for check the endpoint is valid
         }
 
         public static Settings Default
@@ -51,5 +68,36 @@ public static Settings Default
                 return new Settings(section);
             }
         }
+
+        /// <summary>
+        /// Get the vsock address from the endpoint.
+        /// </summary>
+        /// <returns>The vsock address. If the endpoint type is not vsock, return null.</returns>
+        /// <exception cref="FormatException">If the endpoint is invalid.</exception>
+        internal VsockAddress? GetVsockAddress()
+        {
+            if (EndpointType != EndpointVsock) return null;
+
+            var endpoint = Endpoint;
+            if (Endpoint.StartsWith("http://"))
+            {
+                endpoint = endpoint.Substring("http://".Length);
+            }
+            else if (Endpoint.StartsWith("https://"))
+            {
+                endpoint = endpoint.Substring("https://".Length);
+            }
+
+            var parts = endpoint.Split(':', 2);
+            if (parts.Length != 2) throw new FormatException($"Invalid vsock endpoint: {Endpoint}");
+            try
+            {
+                return new VsockAddress(int.Parse(parts[0]), int.Parse(parts[1]));
+            }
+            catch
+            {
+                throw new FormatException($"Invalid vsock endpoint: {Endpoint}");
+            }
+        }
     }
 }

src/Plugins/SignClient/SignClient.cs

@@ -66,9 +66,8 @@ private void Reset(string name, SecureSign.SecureSignClient? client)
             if (!string.IsNullOrEmpty(_name)) SignerManager.RegisterSigner(_name, this);
         }
 
-        private void Reset(Settings settings)
+        private ServiceConfig GetServiceConfig(Settings settings)
         {
-            // _settings = settings;
             var methodConfig = new MethodConfig
             {
                 Names = { MethodName.Default },
@@ -91,10 +90,24 @@ private void Reset(Settings settings)
                 }
             };
 
-            var channel = GrpcChannel.ForAddress(settings.Endpoint, new GrpcChannelOptions
+            return new ServiceConfig { MethodConfigs = { methodConfig } };
+        }
+
+        private void Reset(Settings settings)
+        {
+            // _settings = settings;
+            var serviceConfig = GetServiceConfig(settings);
+            var vsockAddress = settings.GetVsockAddress();
+
+            GrpcChannel channel;
+            if (vsockAddress is not null)
             {
-                ServiceConfig = new ServiceConfig { MethodConfigs = { methodConfig } }
-            });
+                channel = Vsock.CreateChannel(vsockAddress, serviceConfig);
+            }
+            else
+            {
+                channel = GrpcChannel.ForAddress(settings.Endpoint, new() { ServiceConfig = serviceConfig });
+            }
 
             _channel?.Dispose();
             _channel = channel;

src/Plugins/SignClient/SignClient.csproj

@@ -25,6 +25,8 @@
     <PackageReference Include="Grpc.Net.Client" Version="2.70.0" />
     <!-- NOTE: Need install rosetta2 on macOS ARM64 -->
     <PackageReference Include="Grpc.Tools" Version="2.70.0" PrivateAssets="all" />
+
+    <PackageReference Include="Ookii.VmSockets" Version="1.0.0" />
   </ItemGroup>
 
   <ItemGroup>

src/Plugins/SignClient/SignClient.json

@@ -1,6 +1,7 @@
 {
   "PluginConfiguration": {
     "Name": "SignClient",
-    "Endpoint": "http://127.0.0.1:9991"
+    "EndpointType": "tcp", // "tcp" or "vsock"
+    "Endpoint": "http://127.0.0.1:9991" // tcp: "http://127.0.0.1:port", vsock: "http://contextId:port"
   }
 }

src/Plugins/SignClient/Vsock.cs

@@ -0,0 +1,83 @@
+// Copyright (C) 2015-2025 The Neo Project.
+//
+// Vsock.cs file belongs to the neo project and is free
+// software distributed under the MIT software license, see the
+// accompanying file LICENSE in the main directory of the
+// repository or http://www.opensource.org/licenses/mit-license.php
+// for more details.
+//
+// Redistribution and use in source and binary forms with or without
+// modifications are permitted.
+
+using Grpc.Net.Client;
+using Grpc.Net.Client.Configuration;
+using Ookii.VmSockets;
+using System.Net.Sockets;
+
+namespace Neo.Plugins.SignClient
+{
+    /// <summary>
+    /// The address of the vsock address.
+    /// </summary>
+    public record VsockAddress(int ContextId, int Port);
+
+    /// <summary>
+    /// Grpc adapter for VSock. Only supported on Linux.
+    /// This is for the SignClient plugin to connect to the AWS Nitro Enclave.
+    /// </summary>
+    public class Vsock
+    {
+        private readonly VSockEndPoint _endpoint;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="Vsock"/> class.
+        /// </summary>
+        /// <param name="address">The vsock address.</param>
+        public Vsock(VsockAddress address)
+        {
+            if (!OperatingSystem.IsLinux()) throw new PlatformNotSupportedException("Vsock is only supported on Linux.");
+
+            _endpoint = new VSockEndPoint(address.ContextId, address.Port);
+        }
+
+        internal async ValueTask<Stream> ConnectAsync(SocketsHttpConnectionContext context, CancellationToken cancellationToken)
+        {
+            if (!OperatingSystem.IsLinux()) throw new PlatformNotSupportedException("Vsock is only supported on Linux.");
+
+            var socket = VSock.Create(SocketType.Stream);
+            try
+            {
+                // Have to use `Task.Run` with `Connect` to avoid some compatibility issues(if use ConnectAsync).
+                await Task.Run(() => socket.Connect(_endpoint), cancellationToken);
+                return new NetworkStream(socket, true);
+            }
+            catch
+            {
+                socket.Dispose();
+                throw;
+            }
+        }
+
+        /// <summary>
+        /// Creates a Grpc channel for the vsock endpoint.
+        /// </summary>
+        /// <param name="address">The vsock address.</param>
+        /// <param name="serviceConfig">The Grpc service config.</param>
+        /// <returns>The Grpc channel.</returns>
+        public static GrpcChannel CreateChannel(VsockAddress address, ServiceConfig serviceConfig)
+        {
+            var vsock = new Vsock(address);
+            var socketsHttpHandler = new SocketsHttpHandler
+            {
+                ConnectCallback = vsock.ConnectAsync,
+            };
+
+            var addressPlaceholder = $"http://127.0.0.1:{address.Port}"; // just a placeholder
+            return GrpcChannel.ForAddress(addressPlaceholder, new GrpcChannelOptions
+            {
+                HttpHandler = socketsHttpHandler,
+                ServiceConfig = serviceConfig,
+            });
+        }
+    }
+}

tests/Neo.Plugins.SignClient.Tests/UT_SignClient.cs

@@ -44,15 +44,23 @@ public class UT_SignClient
 
         private static SignClient NewClient(Block? block, ExtensiblePayload? payload)
         {
-            // for test sign service, set SIGN_SERVICE_ENDPOINT env
+            // When test sepcific endpoint, set SIGN_SERVICE_ENDPOINT_TYPE and set SIGN_SERVICE_ENDPOINT
+            // For example:
+            // export SIGN_SERVICE_ENDPOINT=http://127.0.0.1:9991
+            // export SIGN_SERVICE_ENDPOINT_TYPE=tcp
+            // or
+            // export SIGN_SERVICE_ENDPOINT=http://2345:9991
+            // export SIGN_SERVICE_ENDPOINT_TYPE=vsock
             var endpoint = Environment.GetEnvironmentVariable("SIGN_SERVICE_ENDPOINT");
+            var endpointType = Environment.GetEnvironmentVariable("SIGN_SERVICE_ENDPOINT_TYPE");
             if (endpoint is not null)
             {
                 var section = new ConfigurationBuilder()
                     .AddInMemoryCollection(new Dictionary<string, string?>
                     {
                         [Settings.SectionName + ":Name"] = "SignClient",
-                        [Settings.SectionName + ":Endpoint"] = endpoint
+                        [Settings.SectionName + ":Endpoint"] = endpoint,
+                        [Settings.SectionName + ":EndpointType"] = endpointType ?? Settings.EndpointTcp
                     })
                     .Build()
                     .GetSection(Settings.SectionName);

tests/Neo.Plugins.SignClient.Tests/UT_Vsock.cs

@@ -0,0 +1,71 @@
+// Copyright (C) 2015-2025 The Neo Project.
+// 
+// UT_Vsock.cs file belongs to the neo project and is free
+// software distributed under the MIT software license, see the
+// accompanying file LICENSE in the main directory of the
+// repository or http://www.opensource.org/licenses/mit-license.php
+// for more details.
+//
+// Redistribution and use in source and binary forms with or without
+// modifications are permitted.
+
+using Microsoft.Extensions.Configuration;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace Neo.Plugins.SignClient.Tests
+{
+    [TestClass]
+    public class UT_Vsock
+    {
+        [TestMethod]
+        public void TestGetVsockAddress()
+        {
+            var address = new VsockAddress(1, 9991);
+            var section = new ConfigurationBuilder()
+                .AddInMemoryCollection(new Dictionary<string, string?>
+                {
+                    ["PluginConfiguration:EndpointType"] = Settings.EndpointVsock,
+                    ["PluginConfiguration:Endpoint"] = $"http://{address.ContextId}:{address.Port}"
+                })
+                .Build()
+                .GetSection("PluginConfiguration");
+
+            var settings = new Settings(section);
+            Assert.AreEqual(address, settings.GetVsockAddress());
+
+            section = new ConfigurationBuilder()
+                .AddInMemoryCollection(new Dictionary<string, string?>
+                {
+                    ["PluginConfiguration:Endpoint"] = "http://127.0.0.1:9991",
+                    ["PluginConfiguration:EndpointType"] = Settings.EndpointTcp
+                })
+                .Build()
+                .GetSection("PluginConfiguration");
+            Assert.IsNull(new Settings(section).GetVsockAddress());
+        }
+
+        [TestMethod]
+        public void TestInvalidEndpoint()
+        {
+            var section = new ConfigurationBuilder()
+                .AddInMemoryCollection(new Dictionary<string, string?>
+                {
+                    ["PluginConfiguration:EndpointType"] = Settings.EndpointVsock,
+                    ["PluginConfiguration:Endpoint"] = "http://127.0.0.1:9991"
+                })
+                .Build()
+                .GetSection("PluginConfiguration");
+            Assert.ThrowsExactly<FormatException>(() => _ = new Settings(section).GetVsockAddress());
+
+            section = new ConfigurationBuilder()
+                .AddInMemoryCollection(new Dictionary<string, string?>
+                {
+                    ["PluginConfiguration:EndpointType"] = "xyz",
+                    ["PluginConfiguration:Endpoint"] = "http://127.0.0.1:9991"
+                })
+                .Build()
+                .GetSection("PluginConfiguration");
+            Assert.ThrowsExactly<FormatException>(() => _ = new Settings(section).GetVsockAddress());
+        }
+    }
+}