runtime: Enable connection to Quote Generation Service (QGS)

For the TD attestation to work the connection to QGS on the host is needed.
By default QGS runs on vsock port 4050, but can be modified by the host owner.
Format of the qemu object follows the SocketAddress structure, so it needs to be provided in the JSON format, as in the example below:
-object '{"qom-type":"tdx-guest","id":"tdx","quote-generation-socket":{"type":"vsock","cid":"2","port":"4050"}}'

Fixes: #9497
Signed-off-by: Jakub Ledworowski <jakub.ledworowski@intel.com>

src/runtime/Makefile

@@ -179,6 +179,7 @@ QEMUVALIDHYPERVISORPATHS := [\"$(QEMUPATH)\"]
 #QEMUTDXPATH := $(QEMUBINDIR)/$(QEMUTDXCMD)
 QEMUTDXPATH := PLACEHOLDER_FOR_DISTRO_QEMU_WITH_TDX_SUPPORT
 QEMUTDXVALIDHYPERVISORPATHS := [\"$(QEMUTDXPATH)\"]
+QEMUTDXQUOTEGENERATIONSERVICESOCKETPORT := 4050
 
 QEMUSNPPATH := $(QEMUBINDIR)/$(QEMUSNPCMD)
 QEMUSNPVALIDHYPERVISORPATHS := [\"$(QEMUSNPPATH)\"]
@@ -705,6 +706,7 @@ USER_VARS += QEMUTDXCMD
 USER_VARS += QEMUSNPCMD
 USER_VARS += QEMUPATH
 USER_VARS += QEMUTDXPATH
+USER_VARS += QEMUTDXQUOTEGENERATIONSERVICESOCKETPORT
 USER_VARS += QEMUSNPPATH
 USER_VARS += QEMUVALIDHYPERVISORPATHS
 USER_VARS += QEMUTDXVALIDHYPERVISORPATHS

src/runtime/config/configuration-qemu-tdx.toml.in

@@ -17,6 +17,7 @@ kernel = "@KERNELCONFIDENTIALPATH@"
 image = "@IMAGECONFIDENTIALPATH@"
 # initrd = "@INITRDPATH@"
 machine_type = "@MACHINETYPE@"
+tdx_quote_generation_service_socket_port = @QEMUTDXQUOTEGENERATIONSERVICESOCKETPORT@
 
 # rootfs filesystem type:
 #   - ext4 (default)

src/runtime/pkg/govmm/qemu/qemu.go

@@ -15,6 +15,7 @@ package qemu
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
 	"io"
 	"log"
@@ -44,6 +45,12 @@ const (
 	MachineTypeMicrovm string = "microvm"
 )
 
+const (
+	// Well known vsock CID for host system.
+	// https://man7.org/linux/man-pages/man7/vsock.7.html
+	VsockHostCid uint64 = 2
+)
+
 // Device is the qemu device interface.
 type Device interface {
 	Valid() bool
@@ -306,6 +313,9 @@ type Object struct {
 
 	// Prealloc enables memory preallocation
 	Prealloc bool
+
+	// QgsPort defines Intel Quote Generation Service port exposed from the host
+	QgsPort uint32
 }
 
 // Valid returns true if the Object structure is valid and complete.
@@ -316,7 +326,7 @@ func (object Object) Valid() bool {
 	case MemoryBackendEPC:
 		return object.ID != "" && object.Size != 0
 	case TDXGuest:
-		return object.ID != "" && object.File != "" && object.DeviceID != ""
+		return object.ID != "" && object.File != "" && object.DeviceID != "" && object.QgsPort != 0
 	case SEVGuest:
 		fallthrough
 	case SNPGuest:
@@ -362,11 +372,7 @@ func (object Object) QemuParams(config *Config) []string {
 		}
 
 	case TDXGuest:
-		objectParams = append(objectParams, string(object.Type))
-		objectParams = append(objectParams, fmt.Sprintf("id=%s", object.ID))
-		if object.Debug {
-			objectParams = append(objectParams, "debug=on")
-		}
+		objectParams = append(objectParams, prepareObjectWithTdxQgs(object))
 		config.Bios = object.File
 	case SEVGuest:
 		fallthrough
@@ -408,6 +414,52 @@ func (object Object) QemuParams(config *Config) []string {
 	return qemuParams
 }
 
+type SocketAddress struct {
+	Type string `json:"type"`
+	Cid  string `json:"cid"`
+	Port string `json:"port"`
+}
+
+type TdxQomObject struct {
+	QomType               string        `json:"qom-type"`
+	Id                    string        `json:"id"`
+	QuoteGenerationSocket SocketAddress `json:"quote-generation-socket"`
+	Debug                 *bool         `json:"debug,omitempty"`
+}
+
+func (this *SocketAddress) String() string {
+	b, err := json.Marshal(*this)
+
+	if err != nil {
+		log.Fatalf("Unable to marshal SocketAddress object: %s", err.Error())
+		return ""
+	}
+
+	return string(b)
+}
+
+func (this *TdxQomObject) String() string {
+	b, err := json.Marshal(*this)
+
+	if err != nil {
+		log.Fatalf("Unable to marshal TDX QOM object: %s", err.Error())
+		return ""
+	}
+
+	return string(b)
+}
+
+func prepareObjectWithTdxQgs(object Object) string {
+	qgsSocket := SocketAddress{"vsock", fmt.Sprint(VsockHostCid), fmt.Sprint(object.QgsPort)}
+	tdxObject := TdxQomObject{string(object.Type), object.ID, qgsSocket, nil}
+
+	if object.Debug {
+		*tdxObject.Debug = true
+	}
+
+	return tdxObject.String()
+}
+
 // Virtio9PMultidev filesystem behaviour to deal
 // with multiple devices being shared with a 9p export.
 type Virtio9PMultidev string

src/runtime/pkg/katautils/config-settings.go.in

@@ -58,6 +58,7 @@ var systemdUnitName = "kata-containers.target"
 
 const defaultKernelParams = ""
 const defaultMachineType = "q35"
+const defaultQgsPort = 4050
 
 const defaultVCPUCount uint32 = 1
 const defaultMaxVCPUCount uint32 = 0

src/runtime/pkg/katautils/config.go

@@ -89,6 +89,7 @@ type hypervisor struct {
 	CPUFeatures                    string                    `toml:"cpu_features"`
 	KernelParams                   string                    `toml:"kernel_params"`
 	MachineType                    string                    `toml:"machine_type"`
+	QgsPort                        uint32                    `toml:"tdx_quote_generation_service_socket_port"`
 	BlockDeviceDriver              string                    `toml:"block_device_driver"`
 	EntropySource                  string                    `toml:"entropy_source"`
 	SharedFS                       string                    `toml:"shared_fs"`
@@ -373,6 +374,14 @@ func (h hypervisor) machineType() string {
 	return h.MachineType
 }
 
+func (h hypervisor) qgsPort() uint32 {
+	if h.QgsPort == 0 {
+		return defaultQgsPort
+	}
+
+	return h.QgsPort
+}
+
 func (h hypervisor) GetEntropySource() string {
 	if h.EntropySource == "" {
 		return defaultEntropySource
@@ -890,6 +899,7 @@ func newQemuHypervisorConfig(h hypervisor) (vc.HypervisorConfig, error) {
 		CPUFeatures:             cpuFeatures,
 		KernelParams:            vc.DeserializeParams(vc.KernelParamFields(kernelParams)),
 		HypervisorMachineType:   machineType,
+		QgsPort:                 h.qgsPort(),
 		NumVCPUsF:               h.defaultVCPUs(),
 		DefaultMaxVCPUs:         h.defaultMaxVCPUs(),
 		MemorySize:              h.defaultMemSz(),

src/runtime/pkg/katautils/config_test.go

@@ -182,6 +182,7 @@ func createAllRuntimeConfigFiles(dir, hypervisor string) (testConfig testRuntime
 		VirtioFSCache:         defaultVirtioFSCacheMode,
 		PFlash:                []string{},
 		SGXEPCSize:            epcSize,
+		QgsPort:               defaultQgsPort,
 	}
 
 	if goruntime.GOARCH == "arm64" && len(hypervisorConfig.PFlash) == 0 && hypervisorConfig.FirmwarePath == "" {

src/runtime/virtcontainers/hypervisor.go

@@ -671,6 +671,9 @@ type HypervisorConfig struct {
 
 	// ExtraMonitorSocket allows to add an extra HMP or QMP socket when the VMM is Qemu
 	ExtraMonitorSocket govmmQemu.MonitorProtocol
+
+	// QgsPort defines Intel Quote Generation Service port exposed from the host
+	QgsPort uint32
 }
 
 // vcpu mapping from vcpu number to thread number

src/runtime/virtcontainers/qemu_amd64.go

@@ -31,6 +31,8 @@ type qemuAmd64 struct {
 	devLoadersCount uint32
 
 	sgxEPCSize int64
+
+	qgsPort uint32
 }
 
 const (
@@ -125,6 +127,7 @@ func newQemuArch(config HypervisorConfig) (qemuArch, error) {
 		},
 		vmFactory: factory,
 		snpGuest:  config.SevSnpGuest,
+		qgsPort:   config.QgsPort,
 	}
 
 	if config.ConfidentialGuest {
@@ -282,6 +285,7 @@ func (q *qemuAmd64) appendProtectionDevice(devices []govmmQemu.Device, firmware,
 			govmmQemu.Object{
 				Driver:         govmmQemu.Loader,
 				Type:           govmmQemu.TDXGuest,
+				QgsPort:        q.qgsPort,
 				ID:             "tdx",
 				DeviceID:       fmt.Sprintf("fd%d", id),
 				Debug:          false,