feat(mirage): add dynamic device naming via manifest and annotations

pkg/unikontainers/types/types.go

@@ -69,15 +69,17 @@ type ProcessConfig struct {
 
 // UnikernelParams holds the data required to build the unikernels commandline
 type UnikernelParams struct {
-	CmdLine    []string // The cmdline provided by the image
-	EnvVars    []string // The environment variables provided by the image
-	Monitor    string   // The monitor where guest will execute
-	Version    string   // The version of the unikernel
-	InitrdPath string   // The path to the initrd of the unikernel
-	Net        NetDevParams
-	Block      []BlockDevParams
-	Rootfs     RootfsParams  // Information about rootfs
-	ProcConf   ProcessConfig // Information for the process execution inside the guest
+	CmdLine       []string // The cmdline provided by the image
+	EnvVars       []string // The environment variables provided by the image
+	Monitor       string   // The monitor where guest will execute
+	Version       string   // The version of the unikernel
+	InitrdPath    string   // The path to the initrd of the unikernel
+	Net           NetDevParams
+	Block         []BlockDevParams
+	Rootfs        RootfsParams  // Information about rootfs
+	ProcConf      ProcessConfig // Information for the process execution inside the guest
+	UnikernelPath string
+	Annotations   map[string]string
 }
 
 // ExecArgs holds the data required by Execve to start the VMM

pkg/unikontainers/unikernels/mirage.go

@@ -15,19 +15,37 @@
 package unikernels
 
 import (
+	"debug/elf"
+	"encoding/json"
 	"fmt"
 	"strings"
 
 	"github.com/urunc-dev/urunc/pkg/unikontainers/types"
 )
 
-const MirageUnikernel string = "mirage"
+const (
+	MirageUnikernel    string = "mirage"
+	AnnotationNetMap          = "urunc.dev/mirage-net-map"
+	AnnotationBlockMap        = "urunc.dev/mirage-block-map"
+)
 
 type Mirage struct {
-	Command string
-	Monitor string
-	Net     MirageNet
-	Block   []MirageBlock
+	Command     string
+	Monitor     string
+	Net         MirageNet
+	Block       []MirageBlock
+	BinaryPath  string
+	Manifest    *Solo5Manifest
+	Annotations map[string]string
+}
+
+type Solo5Manifest struct {
+	Devices []Solo5Device `json:"devices"`
+}
+
+type Solo5Device struct {
+	Name string `json:"name"`
+	Type string `json:"type"`
 }
 
 type MirageNet struct {
@@ -57,8 +75,10 @@ func (m *Mirage) SupportsFS(_ string) bool {
 func (m *Mirage) MonitorNetCli(ifName string, mac string) string {
 	switch m.Monitor {
 	case "hvt", "spt":
-		netOption := "--net:service=" + ifName
-		netOption += " --net-mac:service=" + mac
+		mirageID := m.getMirageDeviceName(ifName, "NET_BASIC", "service")
+
+		netOption := fmt.Sprintf("--net:%s=%s", mirageID, ifName)
+		netOption += fmt.Sprintf(" --net-mac:%s=%s", mirageID, mac)
 		return netOption
 	default:
 		return ""
@@ -81,12 +101,22 @@ func (m *Mirage) MonitorBlockCli() []types.MonitorBlockArgs {
 		// use a single block device. We also need to find some use cases
 		// where multiple block devices are configured in MirageOS and check
 		// how MirageOS handles/configures them.
-		return []types.MonitorBlockArgs{
-			{
-				ID:   "storage",
-				Path: m.Block[0].HostPath,
-			},
+		var blockArgs []types.MonitorBlockArgs
+
+		for i, blk := range m.Block {
+			defaultName := "storage"
+			if i > 0 {
+				defaultName = fmt.Sprintf("storage%d", i)
+			}
+
+			mirageID := m.getMirageDeviceName(blk.ID, "BLOCK_BASIC", defaultName)
+
+			blockArgs = append(blockArgs, types.MonitorBlockArgs{
+				ID:   mirageID,
+				Path: blk.HostPath,
+			})
 		}
+		return blockArgs
 	default:
 		return nil
 	}
@@ -96,8 +126,82 @@ func (m *Mirage) MonitorCli() types.MonitorCliArgs {
 	return types.MonitorCliArgs{}
 }
 
+// getMirageDeviceName determines the correct Solo5 interface name.
+func (m *Mirage) getMirageDeviceName(hostDev string, devType string, defaultName string) string {
+	// 1. Check Annotations
+	var mapKey string
+	if devType == "NET_BASIC" {
+		mapKey = AnnotationNetMap
+	} else {
+		mapKey = AnnotationBlockMap
+	}
+
+	if val, ok := m.Annotations[mapKey]; ok {
+		var mapping map[string]string
+		if err := json.Unmarshal([]byte(val), &mapping); err == nil {
+			if mirageName, found := mapping[hostDev]; found {
+				return mirageName
+			}
+		}
+	}
+
+	// 2. Check Manifest (Auto-detect if only one device exists)
+	if m.Manifest != nil {
+		var validDevs []string
+		for _, dev := range m.Manifest.Devices {
+			if dev.Type == devType {
+				validDevs = append(validDevs, dev.Name)
+			}
+		}
+		if len(validDevs) == 1 {
+			return validDevs[0]
+		}
+	}
+
+	// 3. Fallback
+	return defaultName
+}
+
+// parseSolo5Manifest extracts the .note.solo5.manifest section from the ELF
+func getSolo5Manifest(path string) (*Solo5Manifest, error) {
+	f, err := elf.Open(path)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	section := f.Section(".note.solo5.manifest")
+	if section == nil {
+		return nil, fmt.Errorf("no solo5 manifest section found")
+	}
+
+	data, err := section.Data()
+	if err != nil {
+		return nil, err
+	}
+
+	var manifest Solo5Manifest
+	// Attempt to find the start of the JSON object '{'
+	jsonStart := strings.Index(string(data), "{")
+	if jsonStart == -1 {
+		return nil, fmt.Errorf("invalid manifest format")
+	}
+
+	if err := json.Unmarshal(data[jsonStart:], &manifest); err != nil {
+		return nil, err
+	}
+
+	return &manifest, nil
+}
+
 func (m *Mirage) Init(data types.UnikernelParams) error {
-	// if Mask is empty, there is no network support
+
+	m.BinaryPath = data.UnikernelPath
+	m.Annotations = data.Annotations
+	if manifest, err := getSolo5Manifest(m.BinaryPath); err == nil {
+		m.Manifest = manifest
+	}
+
 	if data.Net.Mask != "" {
 		m.Net.Address = "--ipv4=" + data.Net.IP + "/24"
 		m.Net.Gateway = "--ipv4-gateway=" + data.Net.Gateway

pkg/unikontainers/unikontainers.go

@@ -283,11 +283,13 @@
 	// UnikernelParams
 	// populate unikernel params
 	unikernelParams := types.UnikernelParams{
-		CmdLine:  u.Spec.Process.Args,
-		EnvVars:  u.Spec.Process.Env,
-		Monitor:  vmmType,
-		Version:  unikernelVersion,
-		ProcConf: procAttrs,
+		CmdLine:       u.Spec.Process.Args,
+		EnvVars:       u.Spec.Process.Env,
+		Monitor:       vmmType,
+		Version:       unikernelVersion,
+		ProcConf:      procAttrs,
+		UnikernelPath: u.Unikernel,
+		Annotations:   u.Spec.Annotations,
 	}
 	if len(unikernelParams.CmdLine) == 0 {
 		unikernelParams.CmdLine = strings.Fields(u.State.Annotations[annotCmdLine])