Add DisableCustomSANs and DisableTrustOnFirstUse to GCP provisioner.

Fixes #67

authority/provisioner/aws.go

@@ -118,10 +118,10 @@ type awsInstanceIdentityDocument struct {
 type AWS struct {
 	Type                   string   `json:"type"`
 	Name                   string   `json:"name"`
-	Claims                 *Claims  `json:"claims,omitempty"`
 	Accounts               []string `json:"accounts"`
 	DisableCustomSANs      bool     `json:"disableCustomSANs"`
 	DisableTrustOnFirstUse bool     `json:"disableTrustOnFirstUse"`
+	Claims                 *Claims  `json:"claims,omitempty"`
 	claimer                *Claimer
 	config                 *awsConfig
 }
@@ -192,7 +192,7 @@ func (p *AWS) GetIdentityToken() (string, error) {
 	// Create unique ID for Trust On First Use (TOFU). Only the first instance
 	// per provisioner is allowed as we don't have a way to trust the given
 	// sans.
-	unique := fmt.Sprintf("%s:%s", p.GetID(), idoc.InstanceID)
+	unique := fmt.Sprintf("%s.%s", p.GetID(), idoc.InstanceID)
 	sum := sha256.Sum256([]byte(unique))
 
 	// Create a JWT from the identity document
@@ -256,7 +256,7 @@ func (p *AWS) AuthorizeSign(token string) ([]SignOption, error) {
 
 	// Enforce default DNS and IP if configured.
 	// By default we we'll accept the SANs in the CSR.
-	// There's no way to trust them.
+	// There's no way to trust them other than TOFU.
 	var so []SignOption
 	if p.DisableCustomSANs {
 		so = append(so, dnsNamesValidator([]string{

authority/provisioner/aws_test.go

@@ -0,0 +1,181 @@
+// +build ignore
+
+package provisioner
+
+import (
+	"crypto/x509"
+	"encoding/base64"
+	"encoding/pem"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/fullsailor/pkcs7"
+	"github.com/smallstep/assert"
+)
+
+var rsaCert = `-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----`
+
+var rsaSig = `eYko51V+DBTE/pLMwqH9tekcIGdIL6jGkgmh0faKQbHUrWVfaw2ffx032iqbEkvbqIMx0I4ewl+Cq5IejPQ5ax4+Nb9gSoMHS8VCjAUkpj9dUXPG2DEvTHukpvUTy8fGn1a/3LS5GdEPnDVkMj2QDHDBGskH4eA46x9c069xeyE=`
+
+var dsaCert = `-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----`
+
+var dsaSig = `MIAGCSqGSIb3DQEHAqCAMIACAQExCzAJBgUrDgMCGgUAMIAGCSqGSIb3DQEHAaCAJIAEggHTewog
+ICJwcml2YXRlSXAiIDogIjE3Mi4zMS4yMy40NyIsCiAgImRldnBheVByb2R1Y3RDb2RlcyIgOiBu
+dWxsLAogICJtYXJrZXRwbGFjZVByb2R1Y3RDb2RlcyIgOiBudWxsLAogICJ2ZXJzaW9uIiA6ICIy
+MDE3LTA5LTMwIiwKICAiaW5zdGFuY2VJZCIgOiAiaS0wMmUzYmVjMWY2MDBmNWUzMyIsCiAgImJp
+bGxpbmdQcm9kdWN0cyIgOiBudWxsLAogICJpbnN0YW5jZVR5cGUiIDogInQyLm1pY3JvIiwKICAi
+YXZhaWxhYmlsaXR5Wm9uZSIgOiAidXMtd2VzdC0xYiIsCiAgImtlcm5lbElkIiA6IG51bGwsCiAg
+InJhbWRpc2tJZCIgOiBudWxsLAogICJhY2NvdW50SWQiIDogIjgwNzQ5MjQ3MzI2MyIsCiAgImFy
+Y2hpdGVjdHVyZSIgOiAieDg2XzY0IiwKICAiaW1hZ2VJZCIgOiAiYW1pLTFjMWQyMTdjIiwKICAi
+cGVuZGluZ1RpbWUiIDogIjIwMTctMTEtMjFUMDA6MjU6MjNaIiwKICAicmVnaW9uIiA6ICJ1cy13
+ZXN0LTEiCn0AAAAAAAAxggEYMIIBFAIBATBpMFwxCzAJBgNVBAYTAlVTMRkwFwYDVQQIExBXYXNo
+aW5ndG9uIFN0YXRlMRAwDgYDVQQHEwdTZWF0dGxlMSAwHgYDVQQKExdBbWF6b24gV2ViIFNlcnZp
+Y2VzIExMQwIJAJa6SNnlXhpnMAkGBSsOAwIaBQCgXTAYBgkqhkiG9w0BCQMxCwYJKoZIhvcNAQcB
+MBwGCSqGSIb3DQEJBTEPFw0xODA3MzAyMzMxMDRaMCMGCSqGSIb3DQEJBDEWBBQUze548OLd+uOT
+aOSTDLlV9mevbTAJBgcqhkjOOAQDBC8wLQIUDGeP44Ge1atMQghe+ENV4IDM0zQCFQCBTOEvfKu+
+uscwutj+7RCNgSVaWgAAAAAAAA==`
+
+var doc = `{
+  "privateIp" : "172.31.23.47",
+  "devpayProductCodes" : null,
+  "marketplaceProductCodes" : null,
+  "version" : "2017-09-30",
+  "instanceId" : "i-02e3bec1f600f5e33",
+  "billingProducts" : null,
+  "instanceType" : "t2.micro",
+  "availabilityZone" : "us-west-1b",
+  "kernelId" : null,
+  "ramdiskId" : null,
+  "accountId" : "807492473263",
+  "architecture" : "x86_64",
+  "imageId" : "ami-1c1d217c",
+  "pendingTime" : "2017-11-21T00:25:23Z",
+  "region" : "us-west-1"
+}`
+
+func TestAWSRSA(t *testing.T) {
+	block, _ := pem.Decode([]byte(rsaCert))
+
+	cert, err := x509.ParseCertificate(block.Bytes)
+	assert.FatalError(t, err)
+
+	signature, err := base64.StdEncoding.DecodeString(rsaSig)
+	assert.FatalError(t, err)
+
+	err = cert.CheckSignature(x509.SHA256WithRSA, []byte(doc), signature)
+	assert.FatalError(t, err)
+}
+
+func TestAWSDSA(t *testing.T) {
+	block, _ := pem.Decode([]byte(dsaCert))
+
+	cert, err := x509.ParseCertificate(block.Bytes)
+	assert.FatalError(t, err)
+
+	signature, err := base64.StdEncoding.DecodeString(dsaSig)
+	assert.FatalError(t, err)
+
+	p7, err := pkcs7.Parse(signature)
+	assert.FatalError(t, err)
+
+	p7.Certificates = append(p7.Certificates, cert)
+
+	assert.FatalError(t, p7.Verify())
+}
+
+func TestAWS_GetIdentityToken(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		switch r.URL.Path {
+		case "/document":
+			w.Write([]byte(doc))
+		case "/signature":
+			w.Write([]byte(rsaSig))
+		default:
+			http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
+		}
+	}))
+	defer srv.Close()
+
+	config, err := newAWSConfig()
+	assert.FatalError(t, err)
+	config.identityURL = srv.URL + "/document"
+	config.signatureURL = srv.URL + "/signature"
+
+	type fields struct {
+		Type    string
+		Name    string
+		Claims  *Claims
+		claimer *Claimer
+		config  *awsConfig
+	}
+	tests := []struct {
+		name    string
+		fields  fields
+		want    string
+		wantErr bool
+	}{
+		{"ok", fields{"AWS", "name", nil, nil, config}, "", false},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			p := &AWS{
+				Type:    tt.fields.Type,
+				Name:    tt.fields.Name,
+				Claims:  tt.fields.Claims,
+				claimer: tt.fields.claimer,
+				config:  tt.fields.config,
+			}
+			got, err := p.GetIdentityToken()
+			if (err != nil) != tt.wantErr {
+				t.Errorf("AWS.GetIdentityToken() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if got != tt.want {
+				t.Errorf("AWS.GetIdentityToken() = %v, want %v", got, tt.want)
+			}
+			t.Error(got)
+			// parts := strings.Split(got, ".")
+			// signed, err := base64.RawURLEncoding.DecodeString(parts[0])
+			// assert.FatalError(t, err)
+			// signature, err := base64.RawURLEncoding.DecodeString(parts[1])
+			// assert.FatalError(t, err)
+			// assert.FatalError(t, err, config.certificate.CheckSignature(config.signatureAlgorithm, signed, signature))
+		})
+	}
+}

authority/provisioner/gcp.go

@@ -59,14 +59,23 @@ func newGCPConfig() *gcpConfig {
 
 // GCP is the provisioner that supports identity tokens created by the Google
 // Cloud Platform metadata API.
+//
+// If DisableCustomSANs is true, only the internal DNS and IP will be added as a
+// SAN. By default it will accept any SAN in the CSR.
+//
+// If DisableTrustOnFirstUse is true, multiple sign request for this provisioner
+// with the same instance will be accepted. By default only the first request
+// will be accepted.
 type GCP struct {
-	Type            string   `json:"type"`
+	Type                   string   `json:"type"`
-	Name            string   `json:"name"`
+	Name                   string   `json:"name"`
-	ServiceAccounts []string `json:"serviceAccounts"`
+	ServiceAccounts        []string `json:"serviceAccounts"`
-	Claims          *Claims  `json:"claims,omitempty"`
+	DisableCustomSANs      bool     `json:"disableCustomSANs"`
-	claimer         *Claimer
+	DisableTrustOnFirstUse bool     `json:"disableTrustOnFirstUse"`
-	config          *gcpConfig
+	Claims                 *Claims  `json:"claims,omitempty"`
-	keyStore        *keyStore
+	claimer                *Claimer
+	config                 *gcpConfig
+	keyStore               *keyStore
 }
 
 // GetID returns the provisioner unique identifier. The name should uniquely
@@ -75,24 +84,31 @@ func (p *GCP) GetID() string {
 	return "gcp:" + p.Name
 }
 
-// GetTokenID returns the identifier of the token. For GCP this is the sha256 of
+// GetTokenID returns the identifier of the token. The default value for GCP the
-// "provisioner_id.instance_id.iat.exp".
+// SHA256 of "provisioner_id.instance_id", but if DisableTrustOnFirstUse is set
+// to true, then it will be the SHA256 of the token.
 func (p *GCP) GetTokenID(token string) (string, error) {
 	jwt, err := jose.ParseSigned(token)
 	if err != nil {
 		return "", errors.Wrap(err, "error parsing token")
 	}
 
+	// If TOFU is disabled create an ID for the token, so it cannot be reused.
+	if p.DisableTrustOnFirstUse {
+		sum := sha256.Sum256([]byte(token))
+		return strings.ToLower(hex.EncodeToString(sum[:])), nil
+	}
+
 	// Get claims w/out verification.
 	var claims gcpPayload
 	if err = jwt.UnsafeClaimsWithoutVerification(&claims); err != nil {
 		return "", errors.Wrap(err, "error verifying claims")
 	}
-	// This string should be mostly unique
+
-	unique := fmt.Sprintf("%s.%s.%d.%d",
+	// Create unique ID for Trust On First Use (TOFU). Only the first instance
-		p.GetID(), claims.Google.ComputeEngine.InstanceID,
+	// per provisioner is allowed as we don't have a way to trust the given
-		*claims.IssuedAt, *claims.Expiry,
+	// sans.
-	)
+	unique := fmt.Sprintf("%s.%s", p.GetID(), claims.Google.ComputeEngine.InstanceID)
 	sum := sha256.Sum256([]byte(unique))
 	return strings.ToLower(hex.EncodeToString(sum[:])), nil
 }
@@ -176,20 +192,25 @@ func (p *GCP) AuthorizeSign(token string) ([]SignOption, error) {
 	if err != nil {
 		return nil, err
 	}
-
 	ce := claims.Google.ComputeEngine
-	dnsNames := []string{
+
-		fmt.Sprintf("%s.c.%s.internal", ce.InstanceName, ce.ProjectID),
+	// Enforce default DNS if configured.
-		fmt.Sprintf("%s.%s.c.%s.internal", ce.InstanceName, ce.Zone, ce.ProjectID),
+	// By default we we'll accept the SANs in the CSR.
+	// There's no way to trust them other than TOFU.
+	var so []SignOption
+	if p.DisableCustomSANs {
+		so = append(so, dnsNamesValidator([]string{
+			fmt.Sprintf("%s.c.%s.internal", ce.InstanceName, ce.ProjectID),
+			fmt.Sprintf("%s.%s.c.%s.internal", ce.InstanceName, ce.Zone, ce.ProjectID),
+		}))
 	}
 
-	return []SignOption{
+	return append(so,
 		commonNameValidator(ce.InstanceName),
-		dnsNamesValidator(dnsNames),
 		profileDefaultDuration(p.claimer.DefaultTLSCertDuration()),
 		newProvisionerExtensionOption(TypeGCP, p.Name, claims.Subject),
 		newValidityValidator(p.claimer.MinTLSCertDuration(), p.claimer.MaxTLSCertDuration()),
-	}, nil
+	), nil
 }
 
 // AuthorizeRenewal returns an error if the renewal is disabled.

authority/provisioner/gcp_test.go

@@ -44,16 +44,26 @@ func TestGCP_GetTokenID(t *testing.T) {
 	assert.FatalError(t, err)
 	p1.Name = "name"
 
+	p2, err := generateGCP()
+	assert.FatalError(t, err)
+	p2.DisableTrustOnFirstUse = true
+
 	now := time.Now()
 	t1, err := generateGCPToken(p1.ServiceAccounts[0],
 		"https://accounts.google.com", "gcp:name",
 		"instance-id", "instance-name", "project-id", "zone",
 		now, &p1.keyStore.keySet.Keys[0])
 	assert.FatalError(t, err)
+	t2, err := generateGCPToken(p2.ServiceAccounts[0],
+		"https://accounts.google.com", p2.GetID(),
+		"instance-id", "instance-name", "project-id", "zone",
+		now, &p2.keyStore.keySet.Keys[0])
+	assert.FatalError(t, err)
 
-	unique := fmt.Sprintf("gcp:name.instance-id.%d.%d", now.Unix(), now.Add(5*time.Minute).Unix())
+	sum := sha256.Sum256([]byte("gcp:name.instance-id"))
-	sum := sha256.Sum256([]byte(unique))
+	want1 := strings.ToLower(hex.EncodeToString(sum[:]))
-	want := strings.ToLower(hex.EncodeToString(sum[:]))
+	sum = sha256.Sum256([]byte(t2))
+	want2 := strings.ToLower(hex.EncodeToString(sum[:]))
 
 	type args struct {
 		token string
@@ -65,7 +75,8 @@ func TestGCP_GetTokenID(t *testing.T) {
 		want    string
 		wantErr bool
 	}{
-		{"ok", p1, args{t1}, want, false},
+		{"ok", p1, args{t1}, want1, false},
+		{"ok", p2, args{t2}, want2, false},
 		{"fail token", p1, args{"token"}, "", true},
 		{"fail claims", p1, args{"eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.ey.fooo"}, "", true},
 	}
@@ -188,6 +199,10 @@ func TestGCP_AuthorizeSign(t *testing.T) {
 	p1, err := generateGCP()
 	assert.FatalError(t, err)
 
+	p2, err := generateGCP()
+	assert.FatalError(t, err)
+	p2.DisableCustomSANs = true
+
 	aKey, err := generateJSONWebKey()
 	assert.FatalError(t, err)
 
@@ -196,6 +211,12 @@ func TestGCP_AuthorizeSign(t *testing.T) {
 		"instance-id", "instance-name", "project-id", "zone",
 		time.Now(), &p1.keyStore.keySet.Keys[0])
 	assert.FatalError(t, err)
+	t2, err := generateGCPToken(p2.ServiceAccounts[0],
+		"https://accounts.google.com", p2.GetID(),
+		"instance-id", "instance-name", "project-id", "zone",
+		time.Now(), &p2.keyStore.keySet.Keys[0])
+	assert.FatalError(t, err)
+
 	failKey, err := generateGCPToken(p1.ServiceAccounts[0],
 		"https://accounts.google.com", p1.GetID(),
 		"instance-id", "instance-name", "project-id", "zone",
@@ -253,20 +274,22 @@ func TestGCP_AuthorizeSign(t *testing.T) {
 		name    string
 		gcp     *GCP
 		args    args
+		wantLen int
 		wantErr bool
 	}{
-		{"ok", p1, args{t1}, false},
+		{"ok", p1, args{t1}, 4, false},
-		{"fail token", p1, args{"token"}, true},
+		{"ok", p2, args{t2}, 5, false},
-		{"fail key", p1, args{failKey}, true},
+		{"fail token", p1, args{"token"}, 0, true},
-		{"fail iss", p1, args{failIss}, true},
+		{"fail key", p1, args{failKey}, 0, true},
-		{"fail aud", p1, args{failAud}, true},
+		{"fail iss", p1, args{failIss}, 0, true},
-		{"fail exp", p1, args{failExp}, true},
+		{"fail aud", p1, args{failAud}, 0, true},
-		{"fail nbf", p1, args{failNbf}, true},
+		{"fail exp", p1, args{failExp}, 0, true},
-		{"fail service account", p1, args{failServiceAccount}, true},
+		{"fail nbf", p1, args{failNbf}, 0, true},
-		{"fail instance id", p1, args{failInstanceID}, true},
+		{"fail service account", p1, args{failServiceAccount}, 0, true},
-		{"fail instance name", p1, args{failInstanceName}, true},
+		{"fail instance id", p1, args{failInstanceID}, 0, true},
-		{"fail project id", p1, args{failProjectID}, true},
+		{"fail instance name", p1, args{failInstanceName}, 0, true},
-		{"fail zone", p1, args{failZone}, true},
+		{"fail project id", p1, args{failProjectID}, 0, true},
+		{"fail zone", p1, args{failZone}, 0, true},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
@@ -275,11 +298,7 @@ func TestGCP_AuthorizeSign(t *testing.T) {
 				t.Errorf("GCP.AuthorizeSign() error = %v, wantErr %v", err, tt.wantErr)
 				return
 			}
-			if err != nil {
+			assert.Len(t, tt.wantLen, got)
-				assert.Nil(t, got)
-			} else {
-				assert.Len(t, 5, got)
-			}
 		})
 	}
 }