crc-org · openshift-merge-bot · Feb 26, 2025 · Feb 24, 2025 · Feb 25, 2025 · Feb 25, 2025
diff --git a/cmd/vfkit/main.go b/cmd/vfkit/main.go
@@ -20,12 +20,14 @@ limitations under the License.
 package main
 
 import (
+	"bytes"
 	"fmt"
 	"io"
 	"net"
 	"net/http"
 	"os"
 	"os/signal"
+	"path/filepath"
 	"runtime"
 	"syscall"
 	"time"
@@ -36,6 +38,7 @@ import (
 	"github.com/crc-org/vfkit/pkg/rest"
 	restvf "github.com/crc-org/vfkit/pkg/rest/vf"
 	"github.com/crc-org/vfkit/pkg/vf"
+	"github.com/kdomanski/iso9660"
 	log "github.com/sirupsen/logrus"
 
 	"github.com/crc-org/vfkit/pkg/util"
@@ -87,6 +90,16 @@ func newVMConfiguration(opts *cmdline.Options) (*config.VirtualMachine, error) {
 		return nil, err
 	}
 
+	cloudInitISO, err := generateCloudInitImage(opts.CloudInitFiles.GetSlice())
+	if err != nil {
+		return nil, err
+	}
+
+	// if it generated a valid cloudinit config ISO file we add it to the devices
+	if cloudInitISO != "" {
+		opts.Devices = append(opts.Devices, fmt.Sprintf("virtio-blk,path=%s", cloudInitISO))
+	}
+
 	if err := vmConfig.AddDevicesFromCmdLine(opts.Devices); err != nil {
 		return nil, err
 	}
@@ -264,3 +277,92 @@ func startIgnitionProvisionerServer(ignitionReader io.Reader, ignitionSocketPath
 	log.Debugf("ignition socket: %s", ignitionSocketPath)
 	return srv.Serve(listener)
 }
+
+// it generates a cloud init image by taking the files passed by the user
+// as cloud-init expects files with a specific name (e.g user-data, meta-data) we check the filenames to retrieve the correct info
+// if some file is not passed by the user, an empty file will be copied to the cloud-init ISO to
+// guarantee it to work (user-data and meta-data files are mandatory and both must exists, even if they are empty)
+// if both files are missing it returns an error
+func generateCloudInitImage(files []string) (string, error) {
+	if len(files) == 0 {
+		return "", nil
+	}
+
+	configFiles := map[string]io.Reader{
+		"user-data": nil,
+		"meta-data": nil,
+	}
+
+	hasConfigFile := false
+	for _, path := range files {
+		if path == "" {
+			continue
+		}
+		file, err := os.Open(path)
+		if err != nil {
+			return "", err
+		}
+		defer file.Close()
+
+		filename := filepath.Base(path)
+		if _, ok := configFiles[filename]; ok {
+			hasConfigFile = true
+			configFiles[filename] = file
+		}
+	}
+
+	if !hasConfigFile {
+		return "", fmt.Errorf("cloud-init needs user-data and meta-data files to work")
+	}
+
+	return createCloudInitISO(configFiles)
+}
+
+// It generates a temp ISO file containing the files passed by the user
+// It also register an exit handler to delete the file when vfkit exits
+func createCloudInitISO(files map[string]io.Reader) (string, error) {
+	writer, err := iso9660.NewWriter()
+	if err != nil {
+		return "", fmt.Errorf("failed to create writer: %w", err)
+	}
+
+	defer func() {
+		if err := writer.Cleanup(); err != nil {
+			log.Error(err)
+		}
+	}()
+
+	for name, reader := range files {
+		// if reader is nil, we set it to an empty file
+		if reader == nil {
+			reader = bytes.NewReader([]byte{})
+		}
+		err = writer.AddFile(reader, name)
+		if err != nil {
+			return "", fmt.Errorf("failed to add %s file: %w", name, err)
+		}
+	}
+
+	isoFile, err := os.CreateTemp("", "vfkit-cloudinit-")
+	if err != nil {
+		return "", fmt.Errorf("unable to create temporary cloud-init ISO file: %w", err)
+	}
+
+	defer func() {
+		if err := isoFile.Close(); err != nil {
+			log.Error(fmt.Errorf("failed to close cloud-init ISO file: %w", err))
+		}
+	}()
+
+	// register handler to remove isoFile when exiting
+	util.RegisterExitHandler(func() {
+		os.Remove(isoFile.Name())
+	})
+
+	err = writer.WriteTo(isoFile, "cidata")
+	if err != nil {
+		return "", fmt.Errorf("failed to write cloud-init ISO image: %w", err)
+	}
+
+	return isoFile.Name(), nil
+}
diff --git a/cmd/vfkit/main_test.go b/cmd/vfkit/main_test.go
@@ -6,6 +6,7 @@ import (
 	"net"
 	"net/http"
 	"os"
+	"path/filepath"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -42,3 +43,67 @@ func TestStartIgnitionProvisionerServer(t *testing.T) {
 	require.NoError(t, err)
 	assert.Equal(t, ignitionData, body)
 }
+
+func getTestAssetsDir() (string, error) {
+	currentDir, err := os.Getwd()
+	if err != nil {
+		return "", err
+	}
+
+	projectRoot := filepath.Join(currentDir, "../../")
+	return filepath.Join(projectRoot, "test", "assets"), nil
+}
+
+func TestGenerateCloudInitImage(t *testing.T) {
+	assetsDir, err := getTestAssetsDir()
+	require.NoError(t, err)
+
+	iso, err := generateCloudInitImage([]string{
+		filepath.Join(assetsDir, "user-data"),
+		filepath.Join(assetsDir, "meta-data"),
+	})
+	require.NoError(t, err)
+
+	assert.Contains(t, iso, "vfkit-cloudinit")
+
+	_, err = os.Stat(iso)
+	require.NoError(t, err)
+
+	err = os.Remove(iso)
+	require.NoError(t, err)
+}
+
+func TestGenerateCloudInitImageWithMissingFile(t *testing.T) {
+	assetsDir, err := getTestAssetsDir()
+	require.NoError(t, err)
+
+	iso, err := generateCloudInitImage([]string{
+		filepath.Join(assetsDir, "user-data"),
+	})
+	require.NoError(t, err)
+
+	assert.Contains(t, iso, "vfkit-cloudinit")
+
+	_, err = os.Stat(iso)
+	require.NoError(t, err)
+
+	err = os.Remove(iso)
+	require.NoError(t, err)
+}
+
+func TestGenerateCloudInitImageWithWrongFile(t *testing.T) {
+	assetsDir, err := getTestAssetsDir()
+	require.NoError(t, err)
+
+	iso, err := generateCloudInitImage([]string{
+		filepath.Join(assetsDir, "seed.img"),
+	})
+	assert.Empty(t, iso)
+	require.Error(t, err, "cloud-init needs user-data and meta-data files to work")
+}
+
+func TestGenerateCloudInitImageWithNoFile(t *testing.T) {
+	iso, err := generateCloudInitImage([]string{})
+	assert.Empty(t, iso)
+	require.NoError(t, err)
+}
diff --git a/doc/usage.md b/doc/usage.md
@@ -160,8 +160,24 @@ A copy-on-write image can be created using `cp -c` or [clonefile(2)](http://www.
 #### Cloud-init
 
 The `--device virtio-blk` option can also be used to supply an initial configuration to cloud-init through a disk image.
+Vfkit can create this ISO image automatically, or you can provide a pre-made ISO.
 
-The ISO image file must be labelled cidata or CIDATA and it must contain the user-data and meta-data files.
+##### Automatic ISO Creation
+
+Vfkit allows you to pass the file paths of your `user-data` and `meta-data` files directly as arguments. 
+It will then handle the creation of the ISO image and the virtio-blk device internally.
+
+Example
+```
+--cloud-init /Users/virtuser/user-data,/Users/virtuser/meta-data
+```
+
+N.B: Vfkit detects the files by using their names so make sure to save them as `user-data` and `meta-data`.
+
+##### Manual ISO Creation
+
+Alternatively, you can create the ISO image yourself. 
+The ISO image file must be labelled cidata or CIDATA and it must contain the user-data and meta-data files. 
 It is also possible to add further configurations by using the network-config and vendor-data files.
 See https://cloudinit.readthedocs.io/en/latest/reference/datasources/nocloud.html#runtime-configurations for more details.
 
@@ -188,6 +204,11 @@ To also provide the cloud-init configuration you can add an additional virtio-bl
 --device virtio-blk,path=/Users/virtuser/cloudinit.img
 ```
 
+If you prefer to use the automatic ISO creation 
+```
+--cloud-init /Users/virtuser/user-data,/Users/virtuser/meta-data
+```
+
 
 ### NVM Express
 

diff --git a/go.mod b/go.mod
@@ -8,6 +8,7 @@ require (
 	github.com/containers/common v0.60.4
 	github.com/crc-org/crc/v2 v2.47.0
 	github.com/gin-gonic/gin v1.10.0
+	github.com/kdomanski/iso9660 v0.4.0
 	github.com/prashantgupta24/mac-sleep-notifier v1.0.1
 	github.com/sirupsen/logrus v1.9.3
 	github.com/spf13/cobra v1.8.1

diff --git a/go.sum b/go.sum
@@ -62,6 +62,8 @@ github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2
 github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
 github.com/json-iterator/go v1.1.12 h1:PV8peI4a0ysnczrg+LtxykD8LfKY9ML6u2jnxaEnrnM=
 github.com/json-iterator/go v1.1.12/go.mod h1:e30LSqwooZae/UwlEbR2852Gd8hjQvJoHmT4TnhNGBo=
+github.com/kdomanski/iso9660 v0.4.0 h1:BPKKdcINz3m0MdjIMwS0wx1nofsOjxOq8TOr45WGHFg=
+github.com/kdomanski/iso9660 v0.4.0/go.mod h1:OxUSupHsO9ceI8lBLPJKWBTphLemjrCQY8LPXM7qSzU=
 github.com/klauspost/compress v1.17.11 h1:In6xLpyWOi1+C7tXUUWv2ot1QvBjxevKAaI6IXrJmUc=
 github.com/klauspost/compress v1.17.11/go.mod h1:pMDklpSncoRMuLFrf1W9Ss9KT+0rH90U12bZKk7uwG0=
 github.com/klauspost/cpuid/v2 v2.0.9/go.mod h1:FInQzS24/EEf25PyTYn52gqo7WaD8xa0213Md/qVLRg=

diff --git a/pkg/cmdline/cmdline.go b/pkg/cmdline/cmdline.go
@@ -25,6 +25,8 @@ type Options struct {
 	UseGUI bool
 
 	IgnitionPath string
+
+	CloudInitFiles stringSliceValue
 }
 
 const DefaultRestfulURI = "none://"
@@ -53,5 +55,5 @@ func AddFlags(cmd *cobra.Command, opts *Options) {
 	cmd.Flags().StringVar(&opts.RestfulURI, "restful-uri", DefaultRestfulURI, "URI address for RESTful services")
 
 	cmd.Flags().StringVar(&opts.IgnitionPath, "ignition", "", "path to the ignition file")
-
+	cmd.Flags().VarP(&opts.CloudInitFiles, "cloud-init", "", "path to user-data and meta-data cloud-init configuration files")
 }
diff --git a/test/assets/meta-data b/test/assets/meta-data
diff --git a/test/assets/user-data b/test/assets/user-data
@@ -0,0 +1,17 @@
+#cloud-config
+users:
+  - name: core
+    sudo: ALL=(ALL) NOPASSWD:ALL
+    shell: /bin/bash
+    groups: users
+    lock_passwd: false
+    ssh_authorized_keys:
+      - ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIDAcKzAecDf0R0mrLhO2eswdq6YRpLUFN4JNonl71Dud
+  - name: user2
+    sudo: ALL=(ALL) NOPASSWD:ALL
+    shell: /bin/bash
+    groups: users
+    plain_text_passwd: test
+    lock_passwd: false  
+ssh_pwauth: true
+chpasswd: { expire: false }