Add attest and debugVerify command to gotpm

client/attest.go

@@ -39,6 +39,9 @@ type AttestOpts struct {
 	// attestation protocols:
 	// https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.70.4562&rep=rep1&type=pdf
 	Nonce []byte
+	// TCG Event Log to add to the attestation.
+	// If not specified then it take Event Log by calling GetEventLog().
+	TCGEventLog []byte
 	// TCG Canonical Event Log to add to the attestation.
 	// Currently, we only support PCR replay for PCRs orthogonal to those in the
 	// firmware event log, where PCRs 0-9 and 14 are often measured. If the two
@@ -236,8 +239,12 @@ func (k *Key) Attest(opts AttestOpts) (*pb.Attestation, error) {
 		}
 		attestation.Quotes = append(attestation.Quotes, quote)
 	}
-	if attestation.EventLog, err = GetEventLog(k.rw); err != nil {
-		return nil, fmt.Errorf("failed to retrieve TCG Event Log: %w", err)
+	if opts.TCGEventLog == nil {
+		if attestation.EventLog, err = GetEventLog(k.rw); err != nil {
+			return nil, fmt.Errorf("failed to retrieve TCG Event Log: %w", err)
+		}
+	} else {
+		attestation.EventLog = opts.TCGEventLog
 	}
 	if len(opts.CanonicalEventLog) != 0 {
 		attestation.CanonicalEventLog = opts.CanonicalEventLog

cmd/attest.go

@@ -0,0 +1,167 @@
+package cmd
+
+import (
+	"fmt"
+	"io"
+	"strconv"
+
+	"cloud.google.com/go/compute/metadata"
+	"github.com/google/go-tpm-tools/client"
+	"github.com/google/go-tpm-tools/proto/attest"
+	"github.com/google/go-tpm/tpm2"
+	"github.com/spf13/cobra"
+	"google.golang.org/protobuf/proto"
+)
+
+var (
+	key string
+)
+
+var attestationKeys = map[string]map[tpm2.Algorithm]func(rw io.ReadWriter) (*client.Key, error){
+	"AK": {
+		tpm2.AlgRSA: client.AttestationKeyRSA,
+		tpm2.AlgECC: client.AttestationKeyECC,
+	},
+	"gceAK": {
+		tpm2.AlgRSA: client.GceAttestationKeyRSA,
+		tpm2.AlgECC: client.GceAttestationKeyECC,
+	},
+}
+
+// If hardware technology needs a variable length teenonce then please modify the flags description
+var attestCmd = &cobra.Command{
+	Use:   "attest",
+	Short: "Create a remote attestation report",
+	Long: `Gather information for remote attestation.
+The Attestation report contains a quote on all available PCR banks, a way to validate 
+the quote, and a TCG Event Log (Linux only).
+Use --key to specify the type of attestation key. It can be gceAK for GCE attestation
+key or AK for a custom attestation key. By default it uses AK.
+--algo flag overrides the public key algorithm for attestation key. If not provided then
+by default rsa is used.
+--teenonce attaches a 64 bytes extra data to the attestation report of TDX and SEV-SNP 
+hardware and guarantees a fresh quote.
+`,
+	Args: cobra.NoArgs,
+	RunE: func(cmd *cobra.Command, args []string) error {
+
+		rwc, err := openTpm()
+		if err != nil {
+			return err
+		}
+		defer rwc.Close()
+
+		if !(format == "binarypb" || format == "textproto") {
+			return fmt.Errorf("format should be either binarypb or textproto")
+		}
+
+		var attestationKey *client.Key
+		algoToCreateAK, ok := attestationKeys[key]
+		if !ok {
+			return fmt.Errorf("key should be either AK or gceAK")
+		}
+		createFunc := algoToCreateAK[keyAlgo]
+		attestationKey, err = createFunc(rwc)
+		if err != nil {
+			return fmt.Errorf("failed to create attestation key: %v", err)
+		}
+		defer attestationKey.Close()
+
+		attestOpts := client.AttestOpts{}
+		attestOpts.Nonce = nonce
+		if len(teeNonce) != 0 {
+			attestOpts.TEENonce = teeNonce
+			attestOpts.TEEDevice, err = client.CreateSevSnpDevice()
+			if err != nil {
+				return fmt.Errorf("failed to collect TEE attestation report: %v", err)
+			}
+		}
+
+		attestOpts.TCGEventLog, err = client.GetEventLog(rwc)
+		if err != nil {
+			return fmt.Errorf("failed to retrieve TCG Event Log: %w", err)
+		}
+
+		attestation, err := attestationKey.Attest(attestOpts)
+		if err != nil {
+			return fmt.Errorf("failed to collect attestation report : %v", err)
+		}
+
+		if key == "gceAK" {
+			instanceInfo, err := getInstanceInfoFromMetadata()
+			if err != nil {
+				return err
+			}
+			attestation.InstanceInfo = instanceInfo
+		}
+
+		var out []byte
+		if format == "binarypb" {
+			out, err = proto.Marshal(attestation)
+			if err != nil {
+				return fmt.Errorf("failed to marshal attestation proto: %v", attestation)
+			}
+		} else {
+			out = []byte(marshalOptions.Format(attestation))
+		}
+		if _, err := dataOutput().Write(out); err != nil {
+			return fmt.Errorf("failed to write attestation report: %v", err)
+		}
+		return nil
+	},
+}
+
+func getInstanceInfoFromMetadata() (*attest.GCEInstanceInfo, error) {
+
+	var err error
+	instanceInfo := &attest.GCEInstanceInfo{}
+
+	instanceInfo.ProjectId, err = metadata.ProjectID()
+	if err != nil {
+		return nil, err
+	}
+
+	projectNumber, err := metadata.NumericProjectID()
+	if err != nil {
+		return nil, err
+	}
+	instanceInfo.ProjectNumber, err = strconv.ParseUint(projectNumber, 10, 64)
+	if err != nil {
+		return nil, err
+	}
+
+	instanceInfo.Zone, err = metadata.Zone()
+	if err != nil {
+		return nil, err
+	}
+
+	instanceID, err := metadata.InstanceID()
+	if err != nil {
+		return nil, err
+	}
+	instanceInfo.InstanceId, err = strconv.ParseUint(instanceID, 10, 64)
+	if err != nil {
+		return nil, err
+	}
+
+	instanceInfo.InstanceName, err = metadata.InstanceName()
+	if err != nil {
+		return nil, err
+	}
+
+	return instanceInfo, err
+}
+
+func addKeyFlag(cmd *cobra.Command) {
+	cmd.PersistentFlags().StringVar(&key, "key", "AK", "indicates type of attestation key to use <gceAK|AK>")
+}
+
+func init() {
+	RootCmd.AddCommand(attestCmd)
+	addKeyFlag(attestCmd)
+	addNonceFlag(attestCmd)
+	addTeeNonceflag(attestCmd)
+	addPublicKeyAlgoFlag(attestCmd)
+	addOutputFlag(attestCmd)
+	addFormatFlag(attestCmd)
+}