feat: add WSL2 driver

Makefile

@@ -22,6 +22,17 @@ GO_BUILDTAGS += no_vz
 endif
 endif
 
+ifeq ($(GOOS),windows)
+WINVER_MAJOR=$(shell powershell.exe "[System.Environment]::OSVersion.Version.Major")
+ifeq ($(WINVER_MAJOR),10)
+WINVER_BUILD=$(shell powershell.exe "[System.Environment]::OSVersion.Version.Build")
+WINVER_BUILD_HIGH_ENOUGH=$(shell powershell.exe $(WINVER_BUILD) -ge 19041)
+ifeq ($(WINVER_BUILD_HIGH_ENOUGH),False)
+GO_BUILDTAGS += no_wsl
+endif
+endif
+endif
+
 PACKAGE := github.com/lima-vm/lima
 
 VERSION=$(shell git describe --match 'v[0-9]*' --dirty='.m' --always --tags)

cmd/lima-guestagent/daemon_linux.go

@@ -10,6 +10,7 @@ import (
 	"github.com/gorilla/mux"
 	"github.com/lima-vm/lima/pkg/guestagent"
 	"github.com/lima-vm/lima/pkg/guestagent/api/server"
+	"github.com/mdlayher/vsock"
 	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
 )
@@ -21,6 +22,7 @@ func newDaemonCommand() *cobra.Command {
 		RunE:  daemonAction,
 	}
 	daemonCommand.Flags().Duration("tick", 3*time.Second, "tick for polling events")
+	daemonCommand.Flags().Int("vsock-port", 0, "use vsock server instead a UNIX socket")
 	return daemonCommand
 }
 
@@ -30,6 +32,10 @@ func daemonAction(cmd *cobra.Command, _ []string) error {
 	if err != nil {
 		return err
 	}
+	vSockPort, err := cmd.Flags().GetInt("vsock-port")
+	if err != nil {
+		return err
+	}
 	if tick == 0 {
 		return errors.New("tick must be specified")
 	}
@@ -60,13 +66,25 @@ func daemonAction(cmd *cobra.Command, _ []string) error {
 	if err != nil {
 		return err
 	}
-	l, err := net.Listen("unix", socket)
-	if err != nil {
-		return err
-	}
-	if err := os.Chmod(socket, 0777); err != nil {
-		return err
+
+	var l net.Listener
+	if vSockPort != 0 {
+		vsockL, err := vsock.Listen(uint32(vSockPort), nil)
+		if err != nil {
+			return err
+		}
+		l = vsockL
+		logrus.Infof("serving the guest agent on vsock port: %d", vSockPort)
+	} else {
+		socketL, err := net.Listen("unix", socket)
+		if err != nil {
+			return err
+		}
+		if err := os.Chmod(socket, 0777); err != nil {
+			return err
+		}
+		l = socketL
+		logrus.Infof("serving the guest agent on %q", socket)
 	}
-	logrus.Infof("serving the guest agent on %q", socket)
 	return srv.Serve(l)
 }

cmd/lima-guestagent/install_systemd_linux.go

@@ -3,6 +3,7 @@ package main
 import (
 	_ "embed"
 	"errors"
+	"fmt"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -19,11 +20,16 @@ func newInstallSystemdCommand() *cobra.Command {
 		Short: "install a systemd unit (user)",
 		RunE:  installSystemdAction,
 	}
+	installSystemdCommand.Flags().Int("vsock-port", 0, "use vsock server on specified port")
 	return installSystemdCommand
 }
 
-func installSystemdAction(_ *cobra.Command, _ []string) error {
-	unit, err := generateSystemdUnit()
+func installSystemdAction(cmd *cobra.Command, _ []string) error {
+	vsockPort, err := cmd.Flags().GetInt("vsock-port")
+	if err != nil {
+		return err
+	}
+	unit, err := generateSystemdUnit(vsockPort)
 	if err != nil {
 		return err
 	}
@@ -40,11 +46,11 @@ func installSystemdAction(_ *cobra.Command, _ []string) error {
 		return err
 	}
 	logrus.Infof("Written file %q", unitPath)
-	argss := [][]string{
+	args := [][]string{
 		{"daemon-reload"},
 		{"enable", "--now", "lima-guestagent.service"},
 	}
-	for _, args := range argss {
+	for _, args := range args {
 		cmd := exec.Command("systemctl", append([]string{"--system"}, args...)...)
 		cmd.Stdout = os.Stdout
 		cmd.Stderr = os.Stderr
@@ -60,13 +66,20 @@ func installSystemdAction(_ *cobra.Command, _ []string) error {
 //go:embed lima-guestagent.TEMPLATE.service
 var systemdUnitTemplate string
 
-func generateSystemdUnit() ([]byte, error) {
+func generateSystemdUnit(vsockPort int) ([]byte, error) {
 	selfExeAbs, err := os.Executable()
 	if err != nil {
 		return nil, err
 	}
+
+	var args []string
+	if vsockPort != 0 {
+		args = append(args, fmt.Sprintf("--vsock-port %d", vsockPort))
+	}
+
 	m := map[string]string{
 		"Binary": selfExeAbs,
+		"Args":   strings.Join(args, " "),
 	}
 	return textutil.ExecuteTemplate(systemdUnitTemplate, m)
 }

cmd/lima-guestagent/lima-guestagent.TEMPLATE.service

@@ -2,7 +2,7 @@
 Description=lima-guestagent
 
 [Service]
-ExecStart={{.Binary}} daemon
+ExecStart={{.Binary}} daemon {{.Args}}
 Type=simple
 Restart=on-failure
 

cmd/limactl/delete.go

@@ -62,6 +62,7 @@ func deleteInstance(ctx context.Context, inst *store.Instance, force bool) error
 	if err := os.RemoveAll(inst.Dir); err != nil {
 		return fmt.Errorf("failed to remove %q: %w", inst.Dir, err)
 	}
+
 	return nil
 }
 

cmd/limactl/hostagent.go

@@ -98,6 +98,7 @@ func hostagentAction(cmd *cobra.Command, args []string) error {
 		return err
 	}
 	l, err := net.Listen("unix", socket)
+	logrus.Infof("hostagent socket created at %s", socket)
 	if err != nil {
 		return err
 	}

cmd/limactl/shell.go

@@ -184,7 +184,7 @@ func shellAction(cmd *cobra.Command, args []string) error {
 	sshArgs = append(sshArgs, []string{
 		"-q",
 		"-p", strconv.Itoa(inst.SSHLocalPort),
-		"127.0.0.1",
+		inst.SSHAddress,
 		"--",
 		script,
 	}...)

docs/experimental.md

@@ -5,6 +5,7 @@ The following features are experimental and subject to change:
 - `mountType: 9p`
 - `mountType: virtiofs` on Linux
 - `vmType: vz` and relevant configurations (`mountType: virtiofs`, `rosetta`, `[]networks.vzNAT`)
+- `vmType: wsl2` and relevant configurations (`mountType: wsl2`)
 - `arch: riscv64`
 - `video.display: vnc` and relevant configuration (`video.vnc.display`)
 - `mode: user-v2` in `networks.yml` and relevant configuration in `lima.yaml`

docs/mount.md

@@ -106,3 +106,22 @@ mounts:
 - For macOS, the "virtiofs" mount type is supported only on macOS 13 or above with `vmType: vz` config. See also [`vmtype.md`](./vmtype.md).
 - For Linux, the "virtiofs" mount type requires the [Rust version of virtiofsd](https://gitlab.com/virtio-fs/virtiofsd).
   Using the version from QEMU (usually packaged as `qemu-virtiofsd`) will *not* work, as it requires root access to run.
+
+### wsl2
+> **Warning**
+> "wsl2" mode is experimental
+
+| :zap: Requirement | Lima >= 0.18 + (Windows >= 10 Build 19041 OR Windows 11) |
+| ----------------- | -------------------------------------------------------- |
+
+The "wsl2" mount type relies on using WSL2's navite disk sharing, where the root disk is available by default at `/mnt/$DISK_LETTER` (e.g. `/mnt/c/`).
+
+An example configuration:
+```yaml
+vmType: "wsl2"
+mountType: "wsl2"
+```
+
+#### Caveats
+- WSL2 file permissions may not work exactly as expected when accessing files that are natively on the Windows disk ([more info](https://github.com/MicrosoftDocs/WSL/blob/mattw-wsl2-explainer/WSL/file-permissions.md))
+- WSL2's disk sharing system uses a 9P protocol server, making the performance similar to [Lima's 9p](#9p) mode ([more info](https://github.com/MicrosoftDocs/WSL/blob/mattw-wsl2-explainer/WSL/wsl2-architecture.md#wsl-2-architectural-flow))

docs/vmtype.md

@@ -45,3 +45,36 @@ mountType: "virtiofs"
   kernel v6.3 and later should boot, as long as it is booted via GRUB.
   https://github.com/lima-vm/lima/issues/1577#issuecomment-1565625668
   The issue is fixed in macOS 13.5.
+
+## WSL2
+> **Warning**
+> "wsl2" mode is experimental
+
+| :zap: Requirement | Lima >= 0.18 + (Windows >= 10 Build 19041 OR Windows 11) |
+| ----------------- | -------------------------------------------------------- |
+
+"wsl2" option makes use of native virtualization support provided by Windows' `wsl.exe` ([more info](https://learn.microsoft.com/en-us/windows/wsl/about)).
+
+An example configuration:
+```yaml
+# Example to run Fedora using vmType: wsl2
+vmType: wsl2
+images:
+# Source: https://github.com/runfinch/finch-core/blob/main/Dockerfile
+- location: "https://deps.runfinch.com/common/x86-64/finch-rootfs-production-amd64-1690920103.tar.zst"
+  arch: "x86_64"
+  digest: "sha256:53f2e329b8da0f6a25e025d1f6cc262ae228402ba615ad095739b2f0ec6babc9"
+mountType: wsl2 
+containerd:
+  system: true
+  user: false
+```
+
+### Caveats
+- "wsl2" option is only supported on newer versions of Windows (roughly anything since 2019)
+
+### Known Issues
+- "wsl2" currently doesn't support many of Lima's options. See [this file](../pkg/wsl2/wsl_driver_windows.go#35) for the latest supported options.
+- When running lima using "wsl2", `${LIMA_HOME}/<INSTANCE>/serial.log` will not contain kernel boot logs
+- WSL2 requires a `tar` formatted rootfs archive instead of a VM image
+- Windows doesn't ship with ssh.exe, gzip.exe, etc. which are used by Lima at various points. The easiest way around this is to run `winget install -e --id Git.MinGit` (winget is now built in to Windows as well), and add the resulting `C:\Program Files\Git\usr\bin\` directory to your path.

examples/experimental/wsl2.yaml

@@ -0,0 +1,17 @@
+# This template requires Lima v0.18.0 or later and only works on Windows versions
+# that support WSL2 (Windows 10 Build >= 19041, all Windows 11).
+vmType: wsl2
+
+images:
+# Source: https://github.com/runfinch/finch-core/blob/main/Dockerfile
+- location: "https://deps.runfinch.com/common/x86-64/finch-rootfs-production-amd64-1690920103.tar.zst"
+  arch: "x86_64"
+  digest: "sha256:53f2e329b8da0f6a25e025d1f6cc262ae228402ba615ad095739b2f0ec6babc9"
+
+mountType: wsl2
+
+# Use system because of an error when setting up RootlessKit (see https://github.com/microsoft/WSL/issues/8842)
+# There are possible workarounds, just not implemented yet.
+containerd:
+  system: true
+  user: false

go.mod

@@ -51,7 +51,7 @@ require (
 
 require (
 	github.com/Code-Hex/go-infinity-channel v1.0.0 // indirect
-	github.com/Microsoft/go-winio v0.6.1 // indirect
+	github.com/Microsoft/go-winio v0.6.1
 	github.com/VividCortex/ewma v1.2.0 // indirect
 	github.com/a8m/envsubst v1.4.2 // indirect
 	github.com/alecthomas/participle/v2 v2.0.0 // indirect
@@ -89,7 +89,7 @@ require (
 	github.com/mattn/go-colorable v0.1.13 // indirect
 	github.com/mattn/go-runewidth v0.0.14 // indirect
 	github.com/mdlayher/socket v0.4.1 // indirect
-	github.com/mdlayher/vsock v1.2.1 // indirect
+	github.com/mdlayher/vsock v1.2.1
 	github.com/mgutz/ansi v0.0.0-20170206155736-9520e82c474b // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
@@ -103,11 +103,12 @@ require (
 	go.uber.org/atomic v1.7.0 // indirect
 	go.uber.org/multierr v1.7.0 // indirect
 	golang.org/x/crypto v0.12.0 // indirect
-	golang.org/x/mod v0.10.0 // indirect
+	golang.org/x/exp v0.0.0-20230801115018-d63ba01acd4b
+	golang.org/x/mod v0.11.0 // indirect
 	golang.org/x/net v0.14.0 // indirect
 	golang.org/x/oauth2 v0.8.0 // indirect
 	golang.org/x/term v0.11.0 // indirect
-	golang.org/x/text v0.12.0 // indirect
+	golang.org/x/text v0.12.0
 	golang.org/x/time v0.3.0 // indirect
 	golang.org/x/tools v0.9.3 // indirect
 	golang.org/x/xerrors v0.0.0-20220907171357-04be3eba64a2 // indirect

go.sum

@@ -264,14 +264,16 @@ golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5y
 golang.org/x/crypto v0.0.0-20211215153901-e495a2d5b3d3/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
 golang.org/x/crypto v0.12.0 h1:tFM/ta59kqch6LlvYnPa0yx5a83cL2nHflFhYKvv9Yk=
 golang.org/x/crypto v0.12.0/go.mod h1:NF0Gs7EO5K4qLn+Ylc+fih8BSTeIjAP05siRnAh98yw=
+golang.org/x/exp v0.0.0-20230801115018-d63ba01acd4b h1:r+vk0EmXNmekl0S0BascoeeoHk/L7wmaW2QF90K+kYI=
+golang.org/x/exp v0.0.0-20230801115018-d63ba01acd4b/go.mod h1:FXUEEKJgO7OQYeo8N01OfiKP8RXMtf6e8aTskBGqWdc=
 golang.org/x/lint v0.0.0-20200302205851-738671d3881b/go.mod h1:3xt1FjdF8hUf6vQPIChWIBhFzV8gjjsPE/fR3IyQdNY=
 golang.org/x/mod v0.1.1-0.20191105210325-c90efee705ee/go.mod h1:QqPTAvyqsEbceGzBzNggFXnrqF1CaUcvgkdR5Ot7KZg=
 golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
-golang.org/x/mod v0.10.0 h1:lFO9qtOdlre5W1jxS3r/4szv2/6iXxScdzjoBMXNhYk=
-golang.org/x/mod v0.10.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
+golang.org/x/mod v0.11.0 h1:bUO06HqtnRcc/7l71XBe4WcqTZ+3AH1J59zWDDwLKgU=
+golang.org/x/mod v0.11.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
 golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190419010253-1f3472d942ba/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=

pkg/cidata/cidata.TEMPLATE.d/boot/02-wsl2-setup.sh

@@ -0,0 +1,17 @@
+#!/bin/sh
+# This script replaces the cloud-init functionality of creating a user and setting its SSH keys
+# when using a WSL2 VM.
+[ "$LIMA_CIDATA_VMTYPE" = "wsl2" ] || exit 0
+
+# create user
+sudo useradd -u "${LIMA_CIDATA_UID}" "${LIMA_CIDATA_USER}" -d "${LIMA_CIDATA_HOME}"
+sudo mkdir "${LIMA_CIDATA_HOME}"/.ssh/
+sudo cp "${LIMA_CIDATA_MNT}"/ssh_authorized_keys "${LIMA_CIDATA_HOME}"/.ssh/authorized_keys
+sudo chown "${LIMA_CIDATA_USER}" "${LIMA_CIDATA_HOME}"/.ssh/authorized_keys
+
+# add $LIMA_CIDATA_USER to sudoers
+echo "${LIMA_CIDATA_USER} ALL=(ALL) NOPASSWD:ALL" | sudo tee -a /etc/sudoers.d/99_lima_sudoers
+
+# copy some CIDATA to the hardcoded path for requirement checks (TODO: make this not hardcoded)
+sudo mkdir -p /mnt/lima-cidata
+sudo cp "${LIMA_CIDATA_MNT}"/meta-data /mnt/lima-cidata/meta-data

pkg/cidata/cidata.TEMPLATE.d/boot/25-guestagent-base.sh

@@ -40,5 +40,9 @@ else
 	# Remove legacy systemd service
 	rm -f "${LIMA_CIDATA_HOME}/.config/systemd/user/lima-guestagent.service"
 
-	sudo "${LIMA_CIDATA_GUEST_INSTALL_PREFIX}"/bin/lima-guestagent install-systemd
+	if [ "$LIMA_CIDATA_VMTYPE" = "wsl2" ]; then
+		sudo "${LIMA_CIDATA_GUEST_INSTALL_PREFIX}"/bin/lima-guestagent install-systemd --vsock-port "${LIMA_CIDATA_VSOCK_PORT}"
+	else
+		sudo "${LIMA_CIDATA_GUEST_INSTALL_PREFIX}"/bin/lima-guestagent install-systemd
+	fi
 fi

pkg/cidata/cidata.TEMPLATE.d/lima.env

@@ -39,3 +39,5 @@ LIMA_CIDATA_SKIP_DEFAULT_DEPENDENCY_RESOLUTION=1
 {{- else}}
 LIMA_CIDATA_SKIP_DEFAULT_DEPENDENCY_RESOLUTION=
 {{- end}}
+LIMA_CIDATA_VMTYPE={{ .VMType }}
+LIMA_CIDATA_VSOCK_PORT={{ .VSockPort }}