runtime: make SNP IDBlock configurable

For a use case, we want to set the SNP IDBlock, which allows
configuring the AMD ASP to enforce parameters like expected launch
digest at launch. The struct with the config that should be enforced
(IDBlock) is signed. The public key is placed in the auth block and
the signature is verified by the ASP before launch. The digest of the
public key is also part of the attestation report (ID_KEY_DIGESTS).

Signed-off-by: Paul Meyer <katexochen0@gmail.com>

src/runtime/config/configuration-qemu-nvidia-gpu-snp.toml.in

@@ -60,6 +60,18 @@ enable_annotations = @DEFENABLEANNOTATIONS@
 # Your distribution recommends: @QEMUVALIDHYPERVISORPATHS@
 valid_hypervisor_paths = @QEMUSNPVALIDHYPERVISORPATHS@
 
+# SNP 'ID Block' and 'ID Authentication Information Structure'.
+# If one of snp_id_block or snp_id_auth is specified, the other must be specified, too.
+# Notice that the default SNP policy of QEMU (0x30000) is used by Kata, and the IDBlock
+# must be generated with exactly this policy.
+#
+# 96-byte, base64-encoded blob to provide the ‘ID Block’ structure for the
+# SNP_LAUNCH_FINISH command defined in the SEV-SNP firmware ABI (QEMU default: all-zero)
+#snp_id_block = ""
+# 4096-byte, base64-encoded blob to provide the ‘ID Authentication Information Structure’
+# for the SNP_LAUNCH_FINISH command defined in the SEV-SNP firmware ABI (QEMU default: all-zero)
+#snp_id_auth = ""
+
 # Optional space-separated list of options to pass to the guest kernel.
 # For example, use `kernel_params = "vsyscall=emulate"` if you are having
 # trouble running pre-2.15 glibc.

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

@@ -60,6 +60,18 @@ enable_annotations = @DEFENABLEANNOTATIONS@
 # Your distribution recommends: @QEMUVALIDHYPERVISORPATHS@
 valid_hypervisor_paths = @QEMUVALIDHYPERVISORPATHS@
 
+# SNP 'ID Block' and 'ID Authentication Information Structure'.
+# If one of snp_id_block or snp_id_auth is specified, the other must be specified, too.
+# Notice that the default SNP policy of QEMU (0x30000) is used by Kata, and the IDBlock
+# must be generated with exactly this policy.
+#
+# 96-byte, base64-encoded blob to provide the ‘ID Block’ structure for the
+# SNP_LAUNCH_FINISH command defined in the SEV-SNP firmware ABI (QEMU default: all-zero)
+#snp_id_block = ""
+# 4096-byte, base64-encoded blob to provide the ‘ID Authentication Information Structure’
+# for the SNP_LAUNCH_FINISH command defined in the SEV-SNP firmware ABI (QEMU default: all-zero)
+#snp_id_auth = ""
+
 # Optional space-separated list of options to pass to the guest kernel.
 # For example, use `kernel_params = "vsyscall=emulate"` if you are having
 # trouble running pre-2.15 glibc.

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

@@ -318,6 +318,14 @@ type Object struct {
 
 	// QgsPort defines Intel Quote Generation Service port exposed from the host
 	QgsPort uint32
+
+	// SnpIdBlock is the 96-byte, base64-encoded blob to provide the ‘ID Block’ structure
+	// for the SNP_LAUNCH_FINISH command defined in the SEV-SNP firmware ABI (default: all-zero)
+	SnpIdBlock string
+
+	// SnpIdAuth is the 4096-byte, base64-encoded blob to provide the ‘ID Authentication Information Structure’
+	// for the SNP_LAUNCH_FINISH command defined in the SEV-SNP firmware ABI (default: all-zero)
+	SnpIdAuth string
 }
 
 // Valid returns true if the Object structure is valid and complete.
@@ -389,6 +397,12 @@ func (object Object) QemuParams(config *Config) []string {
 		objectParams = append(objectParams, fmt.Sprintf("cbitpos=%d", object.CBitPos))
 		objectParams = append(objectParams, fmt.Sprintf("reduced-phys-bits=%d", object.ReducedPhysBits))
 		objectParams = append(objectParams, "kernel-hashes=on")
+		if object.SnpIdBlock != "" {
+			objectParams = append(objectParams, fmt.Sprintf("id-block=%s", object.SnpIdBlock))
+		}
+		if object.SnpIdAuth != "" {
+			objectParams = append(objectParams, fmt.Sprintf("id-auth=%s", object.SnpIdAuth))
+		}
 		config.Bios = object.File
 	case SecExecGuest:
 		objectParams = append(objectParams, string(object.Type))

src/runtime/pkg/katautils/config.go

@@ -107,6 +107,8 @@ type hypervisor struct {
 	SeccompSandbox                 string                    `toml:"seccompsandbox"`
 	BlockDeviceAIO                 string                    `toml:"block_device_aio"`
 	RemoteHypervisorSocket         string                    `toml:"remote_hypervisor_socket"`
+	SnpIdBlock                     string                    `toml:"snp_id_block"`
+	SnpIdAuth                      string                    `toml:"snp_id_auth"`
 	HypervisorPathList             []string                  `toml:"valid_hypervisor_paths"`
 	JailerPathList                 []string                  `toml:"valid_jailer_paths"`
 	VirtioFSDaemonList             []string                  `toml:"valid_virtio_fs_daemon_paths"`
@@ -986,6 +988,8 @@ func newQemuHypervisorConfig(h hypervisor) (vc.HypervisorConfig, error) {
 		DisableSeLinux:           h.DisableSeLinux,
 		DisableGuestSeLinux:      h.DisableGuestSeLinux,
 		ExtraMonitorSocket:       extraMonitorSocket,
+		SnpIdBlock:               h.SnpIdBlock,
+		SnpIdAuth:                h.SnpIdAuth,
 	}, nil
 }
 

src/runtime/virtcontainers/hypervisor.go

@@ -461,6 +461,14 @@ type HypervisorConfig struct {
 	// The user maps to the uid.
 	User string
 
+	// SnpIdBlock is the 96-byte, base64-encoded blob to provide the ‘ID Block’ structure
+	// for the SNP_LAUNCH_FINISH command defined in the SEV-SNP firmware ABI (default: all-zero)
+	SnpIdBlock string
+
+	// SnpIdAuth is the 4096-byte, base64-encoded blob to provide the ‘ID Authentication Information Structure’
+	// for the SNP_LAUNCH_FINISH command defined in the SEV-SNP firmware ABI (default: all-zero)
+	SnpIdAuth string
+
 	// KernelParams are additional guest kernel parameters.
 	KernelParams []Param
 

src/runtime/virtcontainers/qemu_amd64.go

@@ -13,6 +13,7 @@ import (
 	"time"
 
 	"github.com/kata-containers/kata-containers/src/runtime/virtcontainers/types"
+	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 
 	"github.com/intel-go/cpuid"
@@ -33,6 +34,10 @@ type qemuAmd64 struct {
 	sgxEPCSize int64
 
 	qgsPort uint32
+
+	snpIdBlock string
+
+	snpIdAuth string
 }
 
 const (
@@ -125,9 +130,11 @@ func newQemuArch(config HypervisorConfig) (qemuArch, error) {
 			protection:           noneProtection,
 			legacySerial:         config.LegacySerial,
 		},
-		vmFactory: factory,
-		snpGuest:  config.SevSnpGuest,
-		qgsPort:   config.QgsPort,
+		vmFactory:  factory,
+		snpGuest:   config.SevSnpGuest,
+		qgsPort:    config.QgsPort,
+		snpIdBlock: config.SnpIdBlock,
+		snpIdAuth:  config.SnpIdAuth,
 	}
 
 	if config.ConfidentialGuest {
@@ -233,7 +240,8 @@ func (q *qemuAmd64) enableProtection() error {
 		"machine":                 q.qemuMachine,
 		"kernel-params-debug":     q.kernelParamsDebug,
 		"kernel-params-non-debug": q.kernelParamsNonDebug,
-		"kernel-params":           q.kernelParams})
+		"kernel-params":           q.kernelParams,
+	})
 
 	switch q.protection {
 	case tdxProtection:
@@ -303,15 +311,23 @@ func (q *qemuAmd64) appendProtectionDevice(devices []govmmQemu.Device, firmware,
 				ReducedPhysBits: 1,
 			}), "", nil
 	case snpProtection:
-		return append(devices,
-			govmmQemu.Object{
-				Type:            govmmQemu.SNPGuest,
-				ID:              "snp",
-				Debug:           false,
-				File:            firmware,
-				CBitPos:         cpuid.AMDMemEncrypt.CBitPosition,
-				ReducedPhysBits: 1,
-			}), "", nil
+		obj := govmmQemu.Object{
+			Type:            govmmQemu.SNPGuest,
+			ID:              "snp",
+			Debug:           false,
+			File:            firmware,
+			CBitPos:         cpuid.AMDMemEncrypt.CBitPosition,
+			ReducedPhysBits: 1,
+		}
+		if q.snpIdBlock != "" && q.snpIdAuth != "" {
+			obj.SnpIdBlock = q.snpIdBlock
+			obj.SnpIdAuth = q.snpIdAuth
+		} else if q.snpIdBlock != "" {
+			return nil, "", errors.New("specifying SNP IDBlock without SNP IDAuth is not allowed")
+		} else if q.snpIdAuth != "" {
+			return nil, "", errors.New("specifying SNP IDAuth without SNP IDBlock is not allowed")
+		}
+		return append(devices, obj), "", nil
 	case noneProtection:
 
 		return devices, firmware, nil