feat: AI Agent Sandbox MCP Server v1を実装

Specifications、Design、ImplementationPlanの優先順位を整理し、単一Task実行モデル、typed option優先、設定可能なresource上限、local Ollamaを必須とするRelease Gateを文書化。

.NET 10/C# 14の5 production project、3 test project、E2E Clientを構築。typed YAML、en/ja locale、fixed/user prompt、stdioおよびloopback限定Streamable HTTP、agent_run/agent_status、Session、Ollama text/tool/Vision、TaskGraphとtoken accountingを実装。

Windows sandboxとしてfixed AppContainer、canonical/reparse検査、能力別ACL、path+SHA-256 executable approval、child-process restriction、Job Object、task journal、atomic file transaction、crash recoveryを実装。WFPのIPv4/IPv6 default denyとexact allow、dynamic session、temporary loopback exemption、管理者/BFE診断を追加。

Security/Recovery test、MCP/Ollama integration test、stdio/HTTP Operational E2E、Release Bundle生成・checksum・manifest・fresh extraction検査を追加。Requirement TraceabilityとPhase 0〜11の進捗、初回セットアップ可能なREADMEを整備。

Debug/Release/publish/objをrepository rootのbuild/へ集約し、旧project-local bin/objへの依存を除去。artifacts/とbuild/をGit管理外に設定し、clean checkoutでもsolution buildからE2E Clientまで生成可能にした。

1 files changed, 123 insertions, 0 deletions

diff --git a/src/Agent.Windows/Network/LoopbackExemption.cs b/src/Agent.Windows/Network/LoopbackExemption.cs
new file mode 100644
index 0000000..a3c68ba
--- /dev/null
+++ b/src/Agent.Windows/Network/LoopbackExemption.cs
@@ -0,0 +1,123 @@
+using System.ComponentModel;
+using System.Runtime.InteropServices;
+using System.Security.Principal;
+using Windows.Win32;
+using Windows.Win32.Foundation;
+using Windows.Win32.Security;
+using Windows.Win32.System.Memory;
+
+namespace Agent.Windows.Network;
+
+internal static unsafe class LoopbackExemption
+{
+    private const string MutexName = "Local\\AgentSandboxMcpLoopbackExemption";
+
+    public static bool Contains(SecurityIdentifier sid)
+    {
+        using MutexLease mutex = AcquireMutex();
+        return Read().Any(item => item.Sid.Equals(sid));
+    }
+
+    public static bool Ensure(SecurityIdentifier sid)
+    {
+        using MutexLease mutex = AcquireMutex();
+        List<Entry> entries = Read();
+        if (entries.Any(item => item.Sid.Equals(sid))) return false;
+        entries.Add(new(sid, 0));
+        Write(entries);
+        return true;
+    }
+
+    public static void Remove(SecurityIdentifier sid)
+    {
+        using MutexLease mutex = AcquireMutex();
+        List<Entry> entries = Read();
+        if (entries.RemoveAll(item => item.Sid.Equals(sid)) == 0) return;
+        Write(entries);
+    }
+
+    private static MutexLease AcquireMutex()
+    {
+        var mutex = new Mutex(false, MutexName);
+        try
+        {
+            try
+            {
+                if (!mutex.WaitOne(TimeSpan.FromSeconds(30))) throw new TimeoutException("Timed out waiting for the loopback exemption lock.");
+            }
+            catch (AbandonedMutexException)
+            {
+                // Ownership is granted to this thread when the prior owner died.
+            }
+            return new(mutex);
+        }
+        catch
+        {
+            mutex.Dispose();
+            throw;
+        }
+    }
+
+    private static List<Entry> Read()
+    {
+        uint result = PInvoke.NetworkIsolationGetAppContainerConfig(out uint count, out SID_AND_ATTRIBUTES* native);
+        ThrowIfError(result, "NetworkIsolationGetAppContainerConfig");
+        try
+        {
+            var entries = new List<Entry>(checked((int)count));
+            for (uint index = 0; index < count; index++)
+            {
+                SID_AND_ATTRIBUTES item = native[index];
+                entries.Add(new(new SecurityIdentifier((nint)item.Sid.Value), item.Attributes));
+            }
+            return entries;
+        }
+        finally
+        {
+            HANDLE heap = PInvoke.GetProcessHeap();
+            for (uint index = 0; index < count; index++)
+                if (native[index].Sid.Value is not null) _ = PInvoke.HeapFree(heap, HEAP_FLAGS.HEAP_NONE, native[index].Sid.Value);
+            if (native is not null) _ = PInvoke.HeapFree(heap, HEAP_FLAGS.HEAP_NONE, native);
+        }
+    }
+
+    private static void Write(IReadOnlyList<Entry> entries)
+    {
+        var native = new SID_AND_ATTRIBUTES[entries.Count];
+        var allocations = new List<nint>(entries.Count);
+        try
+        {
+            for (int index = 0; index < entries.Count; index++)
+            {
+                byte[] bytes = new byte[entries[index].Sid.BinaryLength];
+                entries[index].Sid.GetBinaryForm(bytes, 0);
+                void* allocation = NativeMemory.Alloc((nuint)bytes.Length);
+                Marshal.Copy(bytes, 0, (nint)allocation, bytes.Length);
+                allocations.Add((nint)allocation);
+                native[index].Sid = new PSID(allocation);
+                native[index].Attributes = entries[index].Attributes;
+            }
+            ThrowIfError(PInvoke.NetworkIsolationSetAppContainerConfig(native), "NetworkIsolationSetAppContainerConfig");
+        }
+        finally
+        {
+            foreach (nint allocation in allocations) NativeMemory.Free((void*)allocation);
+        }
+    }
+
+    private static void ThrowIfError(uint result, string operation)
+    {
+        if (result != 0) throw new Win32Exception(unchecked((int)result), $"{operation} failed with Win32 error 0x{result:X8}.");
+    }
+
+    private sealed record Entry(SecurityIdentifier Sid, uint Attributes);
+
+    private sealed class MutexLease(Mutex mutex) : IDisposable
+    {
+        public void Dispose()
+        {
+            mutex.ReleaseMutex();
+            mutex.Dispose();
+        }
+    }
+}