POC: Use dockerd as a backend

CMakeLists.txt

@@ -40,6 +40,26 @@ FetchContent_Declare(nlohmannjson
 FetchContent_MakeAvailable(nlohmannjson)
 FetchContent_GetProperties(nlohmannjson SOURCE_DIR NLOHMAN_JSON_SOURCE_DIR)
 
+set(BOOST_VERSION "1.90.0")
+set(BOOST_TARBALL "boost_${BOOST_VERSION}")
+string(REPLACE "." "_" BOOST_TARBALL "${BOOST_TARBALL}")
+
+FetchContent_Declare(
+  boost_headers
+  URL https://archives.boost.io/release/${BOOST_VERSION}/source/${BOOST_TARBALL}.tar.gz
+  # URL_HASH SHA256=TODO
+)
+
+# Download & unpack to boost_headers_SOURCE_DIR (no add_subdirectory!)
+FetchContent_GetProperties(boost_headers)
+if(NOT boost_headers_POPULATED)
+  FetchContent_Populate(boost_headers)
+endif()
+
+# Path where Boost headers reside (root has 'boost/' folder)
+include_directories(${boost_headers_SOURCE_DIR})
+
+
 # Import modules
 list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}/cmake")
 find_package(IDL REQUIRED)

msipackage/package.wix.in

@@ -262,6 +262,12 @@
                     <RegistryValue Value="WSLAProcess" Type="string" />
                 </RegistryKey>
 
+                <!-- WSLAContainerProcess -->
+                <RegistryKey Root="HKCR" Key="CLSID\{3A5DB29D-6D1D-4619-B89D-578EB34C8E52}">
+                    <RegistryValue Name="AppId" Value="{E9B79997-57E3-4201-AECC-6A464E530DD2}" Type="string" />
+                    <RegistryValue Value="WSLAContainerProcess" Type="string" />
+                </RegistryKey>
+
                 <!-- WSLAUserSession -->
                 <RegistryKey Root="HKCR" Key="CLSID\{a9b7a1b9-0671-405c-95f1-e0612cb4ce8f}">
                     <RegistryValue Name="AppId" Value="{E9B79997-57E3-4201-AECC-6A464E530DD2}" Type="string" />

nuget.config

@@ -18,7 +18,7 @@
     </packageRestore>
     <packageSources>
         <clear />
-        <add key="WSL" value="https://pkgs.dev.azure.com/shine-oss/wsl/_packaging/WslDependencies/nuget/v3/index.json" />
+        <add key="WSL" value="C:\\Users\\piboulay\\repos\\Wsl-deps\\wsla-rootfs" />
     </packageSources>
     <disabledPackageSources>
         <!-- Override any User and Computer NuGet package settings to guarantee

packages.config

@@ -23,7 +23,7 @@
   <package id="Microsoft.WSL.LinuxSdk" version="1.20.0" targetFramework="native" />
   <package id="Microsoft.WSL.TestData" version="0.1.0" />
   <package id="Microsoft.WSL.TestDistro" version="2.5.7-47" />
-  <package id="Microsoft.WSL.WslaRootfs" version="0.1.2" />
+  <package id="Microsoft.WSL.WslaRootfs" version="0.1.3" />
   <package id="Microsoft.WSLg" version="1.0.71" />
   <package id="Microsoft.Xaml.Behaviors.WinUI.Managed" version="3.0.0" />
   <package id="StrawberryPerl" version="5.32.1.1" />

src/linux/init/WSLAInit.cpp

@@ -182,6 +182,107 @@ void HandleMessageImpl(wsl::shared::SocketChannel& Channel, const WSLA_OPEN& Mes
     result = 0;
 }
 
+void HandleMessageImpl(wsl::shared::SocketChannel& Channel, const WSLA_UNIX_CONNECT& Message, const gsl::span<gsl::byte>& Buffer)
+{
+    // Make sure to close the channel since no more messages can be processed after this.
+    auto closeChannel = wil::scope_exit([&]() { Channel.Close(); });
+
+    int result = -1;
+
+    auto sendResult = wil::scope_exit([&]() { Channel.SendResultMessage(result); });
+
+    wil::unique_fd socket;
+
+    const auto* path = wsl::shared::string::FromSpan(Buffer, Message.PathOffset);
+    THROW_ERRNO_IF(EINVAL, path == nullptr);
+
+    try
+    {
+        socket = UtilConnectUnix(path);
+        result = 0;
+    }
+    catch (...)
+    {
+        result = wil::ResultFromCaughtException();
+    }
+
+    if (result != 0)
+    {
+        return;
+    }
+
+    sendResult.reset();
+
+    // Relay data between the two sockets.
+    pollfd pollDescriptors[2];
+    pollDescriptors[0].fd = socket.get();
+    pollDescriptors[0].events = POLLIN;
+    pollDescriptors[1].fd = Channel.Socket();
+    pollDescriptors[1].events = POLLIN;
+
+    std::vector<gsl::byte> relayBuffer;
+    while (true)
+    {
+        auto result = poll(pollDescriptors, COUNT_OF(pollDescriptors), -1);
+        THROW_LAST_ERROR_IF(result < 0);
+
+        if (pollDescriptors[0].revents & (POLLIN | POLLHUP | POLLERR))
+        {
+            auto bytesRead = UtilReadBuffer(pollDescriptors[0].fd, relayBuffer);
+            if (bytesRead < 0)
+            {
+                LOG_ERROR("read failed {}", errno);
+                break;
+            }
+            else if (bytesRead == 0)
+            {
+                // Unix socket has been closed.
+                pollDescriptors[0].fd = -1;
+                break;
+            }
+            else
+            {
+                auto bytesWritten = write(Channel.Socket(), relayBuffer.data(), bytesRead);
+                if (bytesWritten < 0)
+                {
+                    LOG_ERROR("write failed {}", errno);
+                    break;
+                }
+            }
+        }
+
+        if (pollDescriptors[1].revents & (POLLIN | POLLHUP | POLLERR))
+        {
+            auto bytesRead = UtilReadBuffer(pollDescriptors[1].fd, relayBuffer);
+            if (bytesRead < 0)
+            {
+                LOG_ERROR("read failed {}", errno);
+                break;
+            }
+            else if (bytesRead == 0)
+            {
+                // hvsocket has been closed.
+                pollDescriptors[1].fd = -1;
+
+                // Shutdown the write side of the socket. This is required so docker know when stdin is EOF for instance.
+                if (shutdown(socket.get(), SHUT_WR) < 0)
+                {
+                    LOG_ERROR("shutdown({}, SHUT_WR) failed {}", socket.get(), errno);
+                }
+            }
+            else
+            {
+                auto bytesWritten = write(socket.get(), relayBuffer.data(), bytesRead);
+                if (bytesWritten < 0)
+                {
+                    LOG_ERROR("write failed {}", errno);
+                    break;
+                }
+            }
+        }
+    }
+}
+
 void HandleMessageImpl(wsl::shared::SocketChannel& Channel, const WSLA_TTY_RELAY& Message, const gsl::span<gsl::byte>&)
 {
     THROW_LAST_ERROR_IF(fcntl(Message.TtyMaster, F_SETFL, O_NONBLOCK) < 0);
@@ -766,7 +867,7 @@ void ProcessMessage(wsl::shared::SocketChannel& Channel, LX_MESSAGE_TYPE Type, c
 {
     try
     {
-        HandleMessage<WSLA_GET_DISK, WSLA_MOUNT, WSLA_EXEC, WSLA_FORK, WSLA_CONNECT, WSLA_WAITPID, WSLA_SIGNAL, WSLA_TTY_RELAY, WSLA_PORT_RELAY, WSLA_OPEN, WSLA_UNMOUNT, WSLA_DETACH, WSLA_ACCEPT, WSLA_WATCH_PROCESSES>(
+        HandleMessage<WSLA_GET_DISK, WSLA_MOUNT, WSLA_EXEC, WSLA_FORK, WSLA_CONNECT, WSLA_WAITPID, WSLA_SIGNAL, WSLA_TTY_RELAY, WSLA_PORT_RELAY, WSLA_OPEN, WSLA_UNMOUNT, WSLA_DETACH, WSLA_ACCEPT, WSLA_WATCH_PROCESSES, WSLA_UNIX_CONNECT>(
             Channel, Type, Buffer);
     }
     catch (...)

src/shared/inc/JsonUtils.h

@@ -62,6 +62,7 @@ T FromJson(const char* Value)
 
 #ifdef WIN32
 
+        WSL_LOG("InvalidJson", TraceLoggingValue(Value, "JsonValue"), TraceLoggingValue(e.what(), "Error"));
         THROW_HR_WITH_USER_ERROR(WSL_E_INVALID_JSON, wsl::shared::Localization::MessageInvalidJson(e.what()));
 
 #else

src/shared/inc/SocketChannel.h

@@ -318,6 +318,11 @@ class SocketChannel
         return m_socket.get();
     }
 
+    auto Release()
+    {
+        return std::move(m_socket);
+    }
+
     bool Connected() const
     {
         return m_socket.get() >= 0;

src/shared/inc/lxinitshared.h

@@ -397,7 +397,8 @@ typedef enum _LX_MESSAGE_TYPE
     LxMessageWSLADetach,
     LxMessageWSLATerminalChanged,
     LxMessageWSLAWatchProcesses,
-    LxMessageWSLAProcessExited
+    LxMessageWSLAProcessExited,
+    LxMessageWSLAUnixConnect,
 } LX_MESSAGE_TYPE,
     *PLX_MESSAGE_TYPE;
 
@@ -509,6 +510,7 @@ inline auto ToString(LX_MESSAGE_TYPE messageType)
         X(LxMessageWSLATerminalChanged)
         X(LxMessageWSLAWatchProcesses)
         X(LxMessageWSLAProcessExited)
+        X(LxMessageWSLAUnixConnect)
 
     default:
         return "<unexpected LX_MESSAGE_TYPE>";
@@ -1881,6 +1883,20 @@ struct WSLA_PROCESS_EXITED
     PRETTY_PRINT(FIELD(Header), FIELD(Pid), FIELD(Code), FIELD(Signaled));
 };
 
+struct WSLA_UNIX_CONNECT
+{
+    static inline auto Type = LxMessageWSLAUnixConnect;
+    using TResponse = RESULT_MESSAGE<int32_t>;
+
+    DECLARE_MESSAGE_CTOR(WSLA_UNIX_CONNECT);
+
+    MESSAGE_HEADER Header;
+    unsigned int PathOffset;
+    char Buffer[];
+
+    PRETTY_PRINT(FIELD(Header), STRING_FIELD(PathOffset));
+};
+
 typedef struct _LX_MINI_INIT_IMPORT_RESULT
 {
     static inline auto Type = LxMiniInitMessageImportResult;

src/windows/common/CMakeLists.txt

@@ -52,6 +52,7 @@ set(SOURCES
 
 set(HEADERS
     ../../../generated/Localization.h
+    ../inc/docker_schema.h
     ../inc/lxssbusclient.h
     ../inc/lxssclient.h
     ../inc/LxssDynamicFunction.h

src/windows/common/WSLAContainerLauncher.cpp

@@ -79,6 +79,19 @@ void wsl::windows::common::WSLAContainerLauncher::AddVolume(const std::wstring&
 }
 
 std::pair<HRESULT, std::optional<RunningWSLAContainer>> WSLAContainerLauncher::LaunchNoThrow(IWSLASession& Session)
+{
+    auto [result, container] = CreateNoThrow(Session);
+    if (FAILED(result))
+    {
+        return std::make_pair(result, std::optional<RunningWSLAContainer>{});
+    }
+
+    result = container.value().Get().Start();
+
+    return std::make_pair(result, std::move(container));
+}
+
+std::pair<HRESULT, std::optional<RunningWSLAContainer>> WSLAContainerLauncher::CreateNoThrow(IWSLASession& Session)
 {
     WSLA_CONTAINER_OPTIONS options{};
     options.Image = m_image.c_str();
@@ -114,4 +127,12 @@ RunningWSLAContainer WSLAContainerLauncher::Launch(IWSLASession& Session)
     THROW_IF_FAILED(result);
 
     return std::move(container.value());
+}
+
+wsl::windows::common::docker_schema::InspectContainer wsl::windows::common::RunningWSLAContainer::Inspect()
+{
+    wil::unique_cotaskmem_ansistring output;
+    THROW_IF_FAILED(m_container->Inspect(&output));
+
+    return wsl::shared::FromJson<docker_schema::InspectContainer>(output.get());
 }

src/windows/common/WSLAContainerLauncher.h

@@ -14,6 +14,7 @@ Module Name:
 
 #pragma once
 #include "WSLAProcessLauncher.h"
+#include "docker_schema.h"
 
 namespace wsl::windows::common {
 
@@ -28,6 +29,7 @@ class RunningWSLAContainer
     WSLA_CONTAINER_STATE State();
     ClientRunningWSLAProcess GetInitProcess();
     void Reset();
+    docker_schema::InspectContainer Inspect();
 
 private:
     wil::com_ptr<IWSLAContainer> m_container;
@@ -52,6 +54,8 @@ class WSLAContainerLauncher : private WSLAProcessLauncher
     void AddVolume(const std::wstring& HostPath, const std::string& ContainerPath, bool ReadOnly);
     void AddPort(uint16_t WindowsPort, uint16_t ContainerPort, int Family);
 
+    std::pair<HRESULT, std::optional<RunningWSLAContainer>> CreateNoThrow(IWSLASession& Session);
+
     RunningWSLAContainer Launch(IWSLASession& Session);
     std::pair<HRESULT, std::optional<RunningWSLAContainer>> LaunchNoThrow(IWSLASession& Session);