Update tests for attestation evidence api

launcher/agent/agent.go

@@ -327,6 +327,7 @@ func (a *agent) AttestationEvidence(_ context.Context, challenge []byte, extraDa
 
 	switch v := attResult.(type) {
 	case *pb.Attestation:
+		v.CanonicalEventLog = cosCel.Bytes()
 		attestation.Quote = &teemodels.VMAttestationQuote{
 			TPMQuote: convertPBToTPMQuote(v),
 		}

launcher/agent/agent_test.go

@@ -6,7 +6,9 @@ import (
 	"crypto"
 	"crypto/rand"
 	"crypto/rsa"
+	"crypto/sha256"
 	"crypto/sha512"
+	_ "embed"
 	"encoding/base64"
 	"errors"
 	"fmt"
@@ -16,6 +18,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/GoogleCloudPlatform/confidential-space/server/extract"
 	"github.com/cenkalti/backoff/v4"
 	"github.com/golang-jwt/jwt/v4"
 	"github.com/google/go-cmp/cmp"
@@ -30,6 +33,7 @@ import (
 	teemodels "github.com/google/go-tpm-tools/launcher/teeserver/models"
 	attestpb "github.com/google/go-tpm-tools/proto/attest"
 	tpmpb "github.com/google/go-tpm-tools/proto/tpm"
+	"github.com/google/go-tpm-tools/server"
 	"github.com/google/go-tpm-tools/verifier"
 	"github.com/google/go-tpm-tools/verifier/fake"
 	"github.com/google/go-tpm-tools/verifier/models"
@@ -652,6 +656,7 @@ func measureFakeEvents(attestAgent AttestationAgent) error {
 type fakeTdxAttestRoot struct {
 	cel           gecel.CEL
 	receivedNonce []byte
+	tdxQuote      []byte
 	deviceRoTS    []DeviceROT
 }
 
@@ -682,7 +687,7 @@ func (f *fakeTdxAttestRoot) Attest(nonce []byte) (any, error) {
 	}
 
 	return &verifier.TDCCELAttestation{
-		TdQuote:           []byte("fake-tdx-quote"),
+		TdQuote:           f.tdxQuote,
 		NvidiaAttestation: nvAtt,
 	}, nil
 }
@@ -698,6 +703,12 @@ func (f *fakeTdxAttestRoot) ComputeNonce(challenge []byte, extraData []byte) []b
 	return finalNonce[:]
 }
 
+//go:embed tdx_quote.b64
+var tdxQuoteB64 string
+
+//go:embed cel.b64
+var celB64 string
+
 func (f *fakeTdxAttestRoot) AddDeviceROTs(deviceRoTS []DeviceROT) {
 	f.deviceRoTS = append(f.deviceRoTS, deviceRoTS...)
 }
@@ -778,8 +789,21 @@ func TestAttestationEvidence_TDX_Success(t *testing.T) {
 		t.Fatal(err)
 	}
 
+	testTDXQuote, err := base64.StdEncoding.DecodeString(tdxQuoteB64)
+	if err != nil {
+		t.Fatalf("failed to decode tdx_quote.b64: %v", err)
+	}
+	testCEL, err := base64.StdEncoding.DecodeString(celB64)
+	if err != nil {
+		t.Fatalf("failed to decode cel.b64: %v", err)
+	}
+	decodedCEL, err := gecel.DecodeToCEL(bytes.NewBuffer(testCEL))
+	if err != nil {
+		t.Fatalf("failed to decode test CEL: %v", err)
+	}
 	fakeRoot := &fakeTdxAttestRoot{
-		cel: gecel.NewConfComputeMR(),
+		cel:      decodedCEL,
+		tdxQuote: testTDXQuote,
 	}
 	attestAgent := &agent{
 		avRot:     fakeRoot,
@@ -802,17 +826,29 @@ func TestAttestationEvidence_TDX_Success(t *testing.T) {
 		t.Fatalf("AttestationEvidence failed: %v", err)
 	}
 
-	if att.Quote.TDXCCELQuote == nil {
-		t.Fatal("expected TDCCELAttestation to be populated for TDX")
+	// Verify the nonce passed to Attest was derived from challenge+extraData.
+	expectedNonce := fakeRoot.ComputeNonce(challenge, extraData)
+	if !bytes.Equal(fakeRoot.receivedNonce, expectedNonce) {
+		t.Errorf("got nonce %x, want %x", fakeRoot.receivedNonce, expectedNonce)
 	}
 
-	if string(att.Quote.TDXCCELQuote.TDQuote) != "fake-tdx-quote" {
-		t.Errorf("got quote %s, want fake-tdx-quote", string(att.Quote.TDXCCELQuote.TDQuote))
+	if att.Quote.TDXCCELQuote == nil {
+		t.Fatal("expected TDXCCELQuote to be populated for TDX")
 	}
-
-	expectedHash := fakeRoot.ComputeNonce(challenge, extraData)
-	if !bytes.Equal(fakeRoot.receivedNonce, expectedHash) {
-		t.Errorf("got nonce %x, want %x", fakeRoot.receivedNonce, expectedHash)
+	if !bytes.Equal(att.Quote.TDXCCELQuote.TDQuote, testTDXQuote) {
+		t.Errorf("TDQuote mismatch: got %x, want %x", att.Quote.TDXCCELQuote.TDQuote, testTDXQuote)
+	}
+	if att.Quote.TPMQuote != nil {
+		t.Error("expected TPMQuote to be nil for TDX attestation")
+	}
+	if len(att.Quote.TDXCCELQuote.CELLaunchEventLog) == 0 {
+		t.Error("expected CELLaunchEventLog to be non-empty after MeasureEvent calls")
+	}
+	if !bytes.Equal(att.Challenge, challenge) {
+		t.Errorf("challenge mismatch: got %x, want %x", att.Challenge, challenge)
+	}
+	if !bytes.Equal(att.ExtraData, extraData) {
+		t.Errorf("extraData mismatch: got %x, want %x", att.ExtraData, extraData)
 	}
 }
 
@@ -827,6 +863,12 @@ func TestAttestationEvidence_TPM_Success(t *testing.T) {
 	}
 	verifierClient := fake.NewClient(fakeSigner)
 
+	ak, err := client.AttestationKeyECC(tpm)
+	if err != nil {
+		t.Fatalf("failed to create AK: %v", err)
+	}
+	defer ak.Close()
+
 	agent, err := CreateAttestationAgent(tpm, client.AttestationKeyECC, verifierClient, placeholderPrincipalFetcher, signaturediscovery.NewFakeClient(), spec.LaunchSpec{
 		Experiments: experiments.Experiments{
 			EnableAttestationEvidence: true,
@@ -854,6 +896,54 @@ func TestAttestationEvidence_TPM_Success(t *testing.T) {
 	if att.Quote.TDXCCELQuote != nil {
 		t.Fatal("expected TDCCELAttestation to be nil for TPM")
 	}
+
+	// Test the evidence can be verified by the server by re-computing the nonce and calling server.VerifyAttestation.
+	extraDataDigest := sha256.Sum256(extraData)
+	challengeData := append(challenge, extraDataDigest[:]...)
+	challengeDigest := sha256.Sum256(challengeData)
+	tpmNonce := sha256.Sum256(append([]byte(teemodels.WorkloadAttestationLabel), challengeDigest[:]...))
+
+	pbAttestation, err := ak.Attest(client.AttestOpts{Nonce: tpmNonce[:]})
+	if err != nil {
+		t.Fatalf("ak.Attest() failed: %v", err)
+	}
+
+	_, err = server.VerifyAttestation(pbAttestation, server.VerifyOpts{
+		Nonce:      tpmNonce[:],
+		TrustedAKs: []crypto.PublicKey{ak.PublicKey()},
+	})
+	if err != nil {
+		t.Errorf("server.VerifyAttestation failed: %v", err)
+	}
+
+	// Test that the COS state can be extracted from the CEL and contains the expected values.
+	decodedCEL, err := gecel.DecodeToCEL(bytes.NewBuffer(att.Quote.TPMQuote.CELLaunchEventLog))
+	if err != nil {
+		t.Fatalf("gecel.DecodeToCEL failed: %v", err)
+	}
+
+	cosState, err := extract.VerifiedCOSState(decodedCEL, uint8(gecel.PCRType))
+	if err != nil {
+		t.Errorf("extract.VerifiedCOSState failed: %v", err)
+	} else {
+		ctr := cosState.GetContainer()
+		if ctr.GetImageReference() != imageRef {
+			t.Errorf("ImageReference: got %q, want %q", ctr.GetImageReference(), imageRef)
+		}
+		if ctr.GetImageDigest() != imageDigest {
+			t.Errorf("ImageDigest: got %q, want %q", ctr.GetImageDigest(), imageDigest)
+		}
+		if ctr.GetImageId() != imageID {
+			t.Errorf("ImageId: got %q, want %q", ctr.GetImageId(), imageID)
+		}
+		if len(ctr.GetArgs()) == 0 || ctr.GetArgs()[0] != arg {
+			t.Errorf("Args[0]: got %v, want %q", ctr.GetArgs(), arg)
+		}
+		if ctr.GetEnvVars()[envK] != envV {
+			t.Errorf("EnvVars[%q]: got %q, want %q", envK, ctr.GetEnvVars()[envK], envV)
+		}
+		t.Logf("extract.VerifiedCOSState succeeded: ImageRef=%s", ctr.GetImageReference())
+	}
 }
 
 type testClient struct {
@@ -956,3 +1046,72 @@ func TestConvertPBToTPMQuote(t *testing.T) {
 		t.Errorf("convertPBToTPMQuote() mismatch (-got +want):\n%s", diff)
 	}
 }
+
+// TestAttestationEvidence_ExperimentDisabled verifies that AttestationEvidence
+// returns an error when the EnableAttestationEvidence experiment flag is off.
+func TestAttestationEvidence_ExperimentDisabled(t *testing.T) {
+	ctx := context.Background()
+	tpm := test.GetTPM(t)
+	defer client.CheckedClose(t, tpm)
+
+	fakeSigner, err := rsa.GenerateKey(rand.Reader, 2048)
+	if err != nil {
+		t.Fatalf("failed to generate signing key: %v", err)
+	}
+	agent, err := CreateAttestationAgent(tpm, client.AttestationKeyECC, fake.NewClient(fakeSigner),
+		placeholderPrincipalFetcher, signaturediscovery.NewFakeClient(),
+		spec.LaunchSpec{ /* EnableAttestationEvidence defaults to false */ },
+		logging.SimpleLogger(), nil)
+	if err != nil {
+		t.Fatalf("failed to create agent: %v", err)
+	}
+	defer agent.Close()
+
+	_, err = agent.AttestationEvidence(ctx, []byte("challenge"), nil)
+	if err == nil {
+		t.Error("expected error when EnableAttestationEvidence is disabled, got nil")
+	}
+}
+
+// TestAttestationEvidence_TDX_NilExtraData verifies that AttestationEvidence
+// handles nil extraData correctly, deriving the nonce from the challenge alone.
+func TestAttestationEvidence_TDX_NilExtraData(t *testing.T) {
+	ctx := context.Background()
+	tpm := test.GetTPM(t)
+	defer client.CheckedClose(t, tpm)
+
+	ak, err := client.AttestationKeyECC(tpm)
+	if err != nil {
+		t.Fatalf("failed to create AK: %v", err)
+	}
+	defer ak.Close()
+
+	fakeRoot := &fakeTdxAttestRoot{
+		cel:      gecel.NewConfComputeMR(),
+		tdxQuote: []byte("fake-tdx-quote"),
+	}
+	attestatAgent := &agent{
+		avRot:     fakeRoot,
+		fetchedAK: ak,
+		launchSpec: spec.LaunchSpec{
+			Experiments: experiments.Experiments{
+				EnableAttestationEvidence: true,
+			},
+		},
+	}
+
+	challenge := []byte("test-challenge")
+	att, err := attestatAgent.AttestationEvidence(ctx, challenge, nil)
+	if err != nil {
+		t.Fatalf("AttestationEvidence failed with nil extraData: %v", err)
+	}
+
+	expectedNonce := fakeRoot.ComputeNonce(challenge, nil)
+	if !bytes.Equal(fakeRoot.receivedNonce, expectedNonce) {
+		t.Errorf("nonce mismatch with nil extraData: got %x, want %x",
+			fakeRoot.receivedNonce, expectedNonce)
+	}
+	if att.ExtraData != nil {
+		t.Errorf("expected nil ExtraData in attestation, got %x", att.ExtraData)
+	}
+}

launcher/agent/cel.b64

@@ -0,0 +1 @@
+AAAAAAgAAAAAAAAAAGwAAAABBAMAAAA1DAAAADBcj1Ug+HHJ6NVVzAyuX2LYGUTZiYZTL7ZCjlLn6OcFs0Z1TMjI519YGBd/RCoLVCVQAAAAagAAAABldXMtd2VzdDEtZG9ja2VyLnBrZy5kZXYvY29uZmlkZW50aWFsLXNwYWNlLWltYWdlcy1kZXYvY3MtaW50ZWctdGVzdC1pbWFnZXMvZ3B1L2N1ZGEtdmVjdG9yLWFkZDpsYXRlc3QAAAAACAAAAAAAAAABbAAAAAEEAwAAADUMAAAAMC6GMbiO5Ha1OVViE1okYl4k20+dG/FhKspzyQW7zfzq+MnQcjtCYZD0FICZxQBYhlAAAABMAQAAAEdzaGEyNTY6Nzc3MDQ5Zjk2OWQ3OTBjN2ZhOWVkZjU3ODNhZDIyYjJkNGZhMjVmMzE2MTJlOTU2MzllYjNiNTA5OGZmODA2NgAAAAAIAAAAAAAAAAJsAAAAAQQDAAAANQwAAAAwg+TbLqOZ96nZlz0Xi42XbMms33HVHznf6Q9XBVJObIr0O1lESST0rhCn8mBI8+P9UAAAAAoCAAAABU5ldmVyAAAAAAgAAAAAAAAAA2wAAAABBAMAAAA1DAAAADAcAE45vuCj6Z7WQw3betTBYywuYknn7EmO70JuLv71jR3G1tFugw35ez59LbmEG3ZQAAAATAMAAABHc2hhMjU2OjFkYjAxNDU4MGFkNDM3NzllM2E0YTJiN2IzYjM5M2VhMzUxN2MyMWVmYzhiZWYzOGY2ZTYxYzBjNzI0Zjg4MzMAAAAACAAAAAAAAAAEbAAAAAEEAwAAADUMAAAAML6vH37T2AJ5sqDKE3SwdXXP1R8yjgHCATOtvh+3ZFfKALpaCx9MKhUWTZpmYSART1AAAAAZBAAAABQvY3VkYS1zYW1wbGVzL3NhbXBsZQAAAAAIAAAAAAAAAAVsAAAAAQQDAAAANQwAAAAwNdmF0h9sWMi2fGvZmNo4LKnRkuHRT9yjUBPTuk9+sj9Ml6V4i1TRP0B0qm61h/FKUAAAAHAFAAAAa1BBVEg9L3Vzci9sb2NhbC9udmlkaWEvYmluOi91c3IvbG9jYWwvY3VkYS9iaW46L3Vzci9sb2NhbC9zYmluOi91c3IvbG9jYWwvYmluOi91c3Ivc2JpbjovdXNyL2Jpbjovc2JpbjovYmluAAAAAAgAAAAAAAAABmwAAAABBAMAAAA1DAAAADBNQYxNZvAOxcHMy8ZMeQg8r6B08U/3wGdjkYZcVzNNnphbSWM/X35cHxfQNMJNTQhQAAAAEgUAAAANTlZBUkNIPXg4Nl82NAAAAAAIAAAAAAAAAAdsAAAAAQQDAAAANQwAAAAw9bF65fsfc3QwygsEFnxIAnUf+yki9FhH9Qs6U5KGQFpNH/4DHC3xBgMCqAk1En6wUAAABTAFAAAFK05WSURJQV9SRVFVSVJFX0NVREE9Y3VkYT49MTIuNSBicmFuZD11bmtub3duLGRyaXZlcj49NDcwLGRyaXZlcjw0NzEgYnJhbmQ9Z3JpZCxkcml2ZXI+PTQ3MCxkcml2ZXI8NDcxIGJyYW5kPXRlc2xhLGRyaXZlcj49NDcwLGRyaXZlcjw0NzEgYnJhbmQ9bnZpZGlhLGRyaXZlcj49NDcwLGRyaXZlcjw0NzEgYnJhbmQ9cXVhZHJvLGRyaXZlcj49NDcwLGRyaXZlcjw0NzEgYnJhbmQ9cXVhZHJvcnR4LGRyaXZlcj49NDcwLGRyaXZlcjw0NzEgYnJhbmQ9bnZpZGlhcnR4LGRyaXZlcj49NDcwLGRyaXZlcjw0NzEgYnJhbmQ9dmFwcHMsZHJpdmVyPj00NzAsZHJpdmVyPDQ3MSBicmFuZD12cGMsZHJpdmVyPj00NzAsZHJpdmVyPDQ3MSBicmFuZD12Y3MsZHJpdmVyPj00NzAsZHJpdmVyPDQ3MSBicmFuZD12d3MsZHJpdmVyPj00NzAsZHJpdmVyPDQ3MSBicmFuZD1jbG91ZGdhbWluZyxkcml2ZXI+PTQ3MCxkcml2ZXI8NDcxIGJyYW5kPXVua25vd24sZHJpdmVyPj01MzUsZHJpdmVyPDUzNiBicmFuZD1ncmlkLGRyaXZlcj49NTM1LGRyaXZlcjw1MzYgYnJhbmQ9dGVzbGEsZHJpdmVyPj01MzUsZHJpdmVyPDUzNiBicmFuZD1udmlkaWEsZHJpdmVyPj01MzUsZHJpdmVyPDUzNiBicmFuZD1xdWFkcm8sZHJpdmVyPj01MzUsZHJpdmVyPDUzNiBicmFuZD1xdWFkcm9ydHgsZHJpdmVyPj01MzUsZHJpdmVyPDUzNiBicmFuZD1udmlkaWFydHgsZHJpdmVyPj01MzUsZHJpdmVyPDUzNiBicmFuZD12YXBwcyxkcml2ZXI+PTUzNSxkcml2ZXI8NTM2IGJyYW5kPXZwYyxkcml2ZXI+PTUzNSxkcml2ZXI8NTM2IGJyYW5kPXZjcyxkcml2ZXI+PTUzNSxkcml2ZXI8NTM2IGJyYW5kPXZ3cyxkcml2ZXI+PTUzNSxkcml2ZXI8NTM2IGJyYW5kPWNsb3VkZ2FtaW5nLGRyaXZlcj49NTM1LGRyaXZlcjw1MzYgYnJhbmQ9dW5rbm93bixkcml2ZXI+PTU1MCxkcml2ZXI8NTUxIGJyYW5kPWdyaWQsZHJpdmVyPj01NTAsZHJpdmVyPDU1MSBicmFuZD10ZXNsYSxkcml2ZXI+PTU1MCxkcml2ZXI8NTUxIGJyYW5kPW52aWRpYSxkcml2ZXI+PTU1MCxkcml2ZXI8NTUxIGJyYW5kPXF1YWRybyxkcml2ZXI+PTU1MCxkcml2ZXI8NTUxIGJyYW5kPXF1YWRyb3J0eCxkcml2ZXI+PTU1MCxkcml2ZXI8NTUxIGJyYW5kPW52aWRpYXJ0eCxkcml2ZXI+PTU1MCxkcml2ZXI8NTUxIGJyYW5kPXZhcHBzLGRyaXZlcj49NTUwLGRyaXZlcjw1NTEgYnJhbmQ9dnBjLGRyaXZlcj49NTUwLGRyaXZlcjw1NTEgYnJhbmQ9dmNzLGRyaXZlcj49NTUwLGRyaXZlcjw1NTEgYnJhbmQ9dndzLGRyaXZlcj49NTUwLGRyaXZlcjw1NTEgYnJhbmQ9Y2xvdWRnYW1pbmcsZHJpdmVyPj01NTAsZHJpdmVyPDU1MQAAAAAIAAAAAAAAAAhsAAAAAQQDAAAANQwAAAAwamav2VvWjshUGxHDBNEezuSn3///cdO+hLvXz5aVa2Y44i4lAuTjQO8Y2r/yQ9yEUAAAACUFAAAAIE5WX0NVREFfQ1VEQVJUX1ZFUlNJT049MTIuNS4zOS0xAAAAAAgAAAAAAAAACWwAAAABBAMAAAA1DAAAADDi61Yl08jz568+8KehhBgpZkE04a9YIO9Yy7rkmROv1DcjCwFb5W1w/DZmI4b1gMlQAAAALAUAAAAnTlZfQ1VEQV9DT01QQVRfUEFDS0FHRT1jdWRhLWNvbXBhdC0xMi01AAAAAAgAAAAAAAAACmwAAAABBAMAAAA1DAAAADAHolpzujE6M39gBRyP+CbBKKea5Uc78nS1nRu/a2PXvYZa5Etq4IDDksxVVRGi8txQAAAAGAUAAAATQ1VEQV9WRVJTSU9OPTEyLjUuMAAAAAAIAAAAAAAAAAtsAAAAAQQDAAAANQwAAAAwa8jVsmvrGFeb7V+2xTc4bRFUmC52m+ewmqdJt5PNWRjtdUFdr7tBec4ZIS9mtDzKUAAAAEIFAAAAPUxEX0xJQlJBUllfUEFUSD0vdXNyL2xvY2FsL252aWRpYS9saWI6L3Vzci9sb2NhbC9udmlkaWEvbGliNjQAAAAACAAAAAAAAAAMbAAAAAEEAwAAADUMAAAAMNXZ184AsMflul47Mv5Cql9fjv3/uoTj7dHMHQhginfbYAjvOCkD7Z8ucyHL8ShvtVAAAAAfBQAAABpOVklESUFfVklTSUJMRV9ERVZJQ0VTPWFsbAAAAAAIAAAAAAAAAA1sAAAAAQQDAAAANQwAAAAwJNJ8BpfoI8HqOuMOnVRefvNOzFYQAbZrT3BYmy9EVTEdQz63VpgQI8OiXTCQBOGkUAAAAC8FAAAAKk5WSURJQV9EUklWRVJfQ0FQQUJJTElUSUVTPWNvbXB1dGUsdXRpbGl0eQAAAAAIAAAAAAAAAA5sAAAAAQQDAAAANQwAAAAwH7QjGvpROWj+2BGJ0Ck/EhR2fTb+6Q+YDjzes5+ARdU9DxVFXlH8iDYjqqM1xPgRUAAAAEsFAAAARkhPU1ROQU1FPWNzLWNncHUtdGVzdC1kODA1ZWEyNi05YjA1LTQwZjgtYWYzYy0yOGM2ZmNlODc5N2ItdGR4Y3ZtLWNncHUAAAAACAAAAAAAAAAPbAAAAAEEAwAAADUMAAAAMA2h+EkJLHVQIyVibZSQWOYNZaCdm3Kj4qlvMLw8Pd/03wNJBmtpeyXA5Lx5M8I9w1AAAAAGCQAAAAEAAAAAAAgAAAAAAAAAEGwAAAABBAMAAAA1DAAAADB2z/xJnq5sjhRwmzT78mx2bqFcM/qMeajS+OHmxVEYNTa89QRiCz6XvwXPwA5ogChQAAAABwoAAAACT04AAAAACAAAAAAAAAARbAAAAAEEAwAAADUMAAAAMCcx/OR3jG+ab6IttOanN1wPRnLUB7Dc0hlmF+fdLTO5NIKBw+BEtUOh3mjN8diJ/1AAAAAFCAAAAAA=