oauth2/google: remove meta validations for aws external credentials

Remove the url validations to keep a consistency with other libraries.

Change-Id: Icb1767edc000d9695db3f0c7ca271918fb2083f5
GitHub-Last-Rev: af89ee0c72
GitHub-Pull-Request: golang/oauth2#660
Reviewed-on: https://go-review.googlesource.com/c/oauth2/+/522395
Reviewed-by: Leo Siracusa <leosiracusa@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cody Oss <codyoss@google.com>
Run-TryBot: Cody Oss <codyoss@google.com>

google/internal/externalaccount/aws.go

@@ -274,49 +274,6 @@ type awsRequest struct {
 	Headers []awsRequestHeader `json:"headers"`
 }
 
-func (cs awsCredentialSource) validateMetadataServers() error {
-	if err := cs.validateMetadataServer(cs.RegionURL, "region_url"); err != nil {
-		return err
-	}
-	if err := cs.validateMetadataServer(cs.CredVerificationURL, "url"); err != nil {
-		return err
-	}
-	return cs.validateMetadataServer(cs.IMDSv2SessionTokenURL, "imdsv2_session_token_url")
-}
-
-var validHostnames []string = []string{"169.254.169.254", "fd00:ec2::254"}
-
-func (cs awsCredentialSource) isValidMetadataServer(metadataUrl string) bool {
-	if metadataUrl == "" {
-		// Zero value means use default, which is valid.
-		return true
-	}
-
-	u, err := url.Parse(metadataUrl)
-	if err != nil {
-		// Unparseable URL means invalid
-		return false
-	}
-
-	for _, validHostname := range validHostnames {
-		if u.Hostname() == validHostname {
-			// If it's one of the valid hostnames, everything is good
-			return true
-		}
-	}
-
-	// hostname not found in our allowlist, so not valid
-	return false
-}
-
-func (cs awsCredentialSource) validateMetadataServer(metadataUrl, urlName string) error {
-	if !cs.isValidMetadataServer(metadataUrl) {
-		return fmt.Errorf("oauth2/google: invalid hostname %s for %s", metadataUrl, urlName)
-	}
-
-	return nil
-}
-
 func (cs awsCredentialSource) doRequest(req *http.Request) (*http.Response, error) {
 	if cs.client == nil {
 		cs.client = oauth2.NewClient(cs.ctx, nil)

google/internal/externalaccount/aws_test.go

@@ -585,25 +585,18 @@ func getExpectedSubjectToken(url, region, accessKeyID, secretAccessKey, security
 func TestAWSCredential_BasicRequest(t *testing.T) {
 	server := createDefaultAwsTestServer()
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 
 	tfc := testFileConfig
 	tfc.CredentialSource = server.getCredentialSource(ts.URL)
 
 	oldGetenv := getenv
 	oldNow := now
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
 		now = oldNow
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{})
 	now = setTime(defaultTime)
-	validHostnames = []string{tsURL.Hostname()}
 
 	base, err := tfc.parse(context.Background())
 	if err != nil {
@@ -631,25 +624,18 @@ func TestAWSCredential_BasicRequest(t *testing.T) {
 func TestAWSCredential_IMDSv2(t *testing.T) {
 	server := createDefaultAwsTestServerWithImdsv2(t)
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 
 	tfc := testFileConfig
 	tfc.CredentialSource = server.getCredentialSource(ts.URL)
 
 	oldGetenv := getenv
 	oldNow := now
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
 		now = oldNow
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{})
 	now = setTime(defaultTime)
-	validHostnames = []string{tsURL.Hostname()}
 
 	base, err := tfc.parse(context.Background())
 	if err != nil {
@@ -677,10 +663,6 @@ func TestAWSCredential_IMDSv2(t *testing.T) {
 func TestAWSCredential_BasicRequestWithoutSecurityToken(t *testing.T) {
 	server := createDefaultAwsTestServer()
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 	delete(server.Credentials, "Token")
 
 	tfc := testFileConfig
@@ -688,15 +670,12 @@ func TestAWSCredential_BasicRequestWithoutSecurityToken(t *testing.T) {
 
 	oldGetenv := getenv
 	oldNow := now
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
 		now = oldNow
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{})
 	now = setTime(defaultTime)
-	validHostnames = []string{tsURL.Hostname()}
 
 	base, err := tfc.parse(context.Background())
 	if err != nil {
@@ -724,21 +703,15 @@ func TestAWSCredential_BasicRequestWithoutSecurityToken(t *testing.T) {
 func TestAWSCredential_BasicRequestWithEnv(t *testing.T) {
 	server := createDefaultAwsTestServer()
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 
 	tfc := testFileConfig
 	tfc.CredentialSource = server.getCredentialSource(ts.URL)
 
 	oldGetenv := getenv
 	oldNow := now
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
 		now = oldNow
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{
 		"AWS_ACCESS_KEY_ID":     "AKIDEXAMPLE",
@@ -746,7 +719,6 @@ func TestAWSCredential_BasicRequestWithEnv(t *testing.T) {
 		"AWS_REGION":            "us-west-1",
 	})
 	now = setTime(defaultTime)
-	validHostnames = []string{tsURL.Hostname()}
 
 	base, err := tfc.parse(context.Background())
 	if err != nil {
@@ -774,21 +746,15 @@ func TestAWSCredential_BasicRequestWithEnv(t *testing.T) {
 func TestAWSCredential_BasicRequestWithDefaultEnv(t *testing.T) {
 	server := createDefaultAwsTestServer()
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 
 	tfc := testFileConfig
 	tfc.CredentialSource = server.getCredentialSource(ts.URL)
 
 	oldGetenv := getenv
 	oldNow := now
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
 		now = oldNow
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{
 		"AWS_ACCESS_KEY_ID":     "AKIDEXAMPLE",
@@ -796,7 +762,6 @@ func TestAWSCredential_BasicRequestWithDefaultEnv(t *testing.T) {
 		"AWS_REGION":            "us-west-1",
 	})
 	now = setTime(defaultTime)
-	validHostnames = []string{tsURL.Hostname()}
 
 	base, err := tfc.parse(context.Background())
 	if err != nil {
@@ -823,21 +788,15 @@ func TestAWSCredential_BasicRequestWithDefaultEnv(t *testing.T) {
 func TestAWSCredential_BasicRequestWithTwoRegions(t *testing.T) {
 	server := createDefaultAwsTestServer()
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 
 	tfc := testFileConfig
 	tfc.CredentialSource = server.getCredentialSource(ts.URL)
 
 	oldGetenv := getenv
 	oldNow := now
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
 		now = oldNow
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{
 		"AWS_ACCESS_KEY_ID":     "AKIDEXAMPLE",
@@ -846,7 +805,6 @@ func TestAWSCredential_BasicRequestWithTwoRegions(t *testing.T) {
 		"AWS_DEFAULT_REGION":    "us-east-1",
 	})
 	now = setTime(defaultTime)
-	validHostnames = []string{tsURL.Hostname()}
 
 	base, err := tfc.parse(context.Background())
 	if err != nil {
@@ -873,25 +831,18 @@ func TestAWSCredential_BasicRequestWithTwoRegions(t *testing.T) {
 func TestAWSCredential_RequestWithBadVersion(t *testing.T) {
 	server := createDefaultAwsTestServer()
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 
 	tfc := testFileConfig
 	tfc.CredentialSource = server.getCredentialSource(ts.URL)
 	tfc.CredentialSource.EnvironmentID = "aws3"
 
 	oldGetenv := getenv
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{})
-	validHostnames = []string{tsURL.Hostname()}
 
-	_, err = tfc.parse(context.Background())
+	_, err := tfc.parse(context.Background())
 	if err == nil {
 		t.Fatalf("parse() should have failed")
 	}
@@ -903,23 +854,16 @@ func TestAWSCredential_RequestWithBadVersion(t *testing.T) {
 func TestAWSCredential_RequestWithNoRegionURL(t *testing.T) {
 	server := createDefaultAwsTestServer()
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 
 	tfc := testFileConfig
 	tfc.CredentialSource = server.getCredentialSource(ts.URL)
 	tfc.CredentialSource.RegionURL = ""
 
 	oldGetenv := getenv
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{})
-	validHostnames = []string{tsURL.Hostname()}
 
 	base, err := tfc.parse(context.Background())
 	if err != nil {
@@ -939,23 +883,17 @@ func TestAWSCredential_RequestWithNoRegionURL(t *testing.T) {
 func TestAWSCredential_RequestWithBadRegionURL(t *testing.T) {
 	server := createDefaultAwsTestServer()
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
+
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 	server.WriteRegion = notFound
 
 	tfc := testFileConfig
 	tfc.CredentialSource = server.getCredentialSource(ts.URL)
 
 	oldGetenv := getenv
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{})
-	validHostnames = []string{tsURL.Hostname()}
 
 	base, err := tfc.parse(context.Background())
 	if err != nil {
@@ -975,10 +913,7 @@ func TestAWSCredential_RequestWithBadRegionURL(t *testing.T) {
 func TestAWSCredential_RequestWithMissingCredential(t *testing.T) {
 	server := createDefaultAwsTestServer()
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
+
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 	server.WriteSecurityCredentials = func(w http.ResponseWriter, r *http.Request) {
 		w.Write([]byte("{}"))
 	}
@@ -987,13 +922,10 @@ func TestAWSCredential_RequestWithMissingCredential(t *testing.T) {
 	tfc.CredentialSource = server.getCredentialSource(ts.URL)
 
 	oldGetenv := getenv
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{})
-	validHostnames = []string{tsURL.Hostname()}
 
 	base, err := tfc.parse(context.Background())
 	if err != nil {
@@ -1013,10 +945,7 @@ func TestAWSCredential_RequestWithMissingCredential(t *testing.T) {
 func TestAWSCredential_RequestWithIncompleteCredential(t *testing.T) {
 	server := createDefaultAwsTestServer()
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
+
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 	server.WriteSecurityCredentials = func(w http.ResponseWriter, r *http.Request) {
 		w.Write([]byte(`{"AccessKeyId":"FOOBARBAS"}`))
 	}
@@ -1025,13 +954,10 @@ func TestAWSCredential_RequestWithIncompleteCredential(t *testing.T) {
 	tfc.CredentialSource = server.getCredentialSource(ts.URL)
 
 	oldGetenv := getenv
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{})
-	validHostnames = []string{tsURL.Hostname()}
 
 	base, err := tfc.parse(context.Background())
 	if err != nil {
@@ -1051,23 +977,16 @@ func TestAWSCredential_RequestWithIncompleteCredential(t *testing.T) {
 func TestAWSCredential_RequestWithNoCredentialURL(t *testing.T) {
 	server := createDefaultAwsTestServer()
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 
 	tfc := testFileConfig
 	tfc.CredentialSource = server.getCredentialSource(ts.URL)
 	tfc.CredentialSource.URL = ""
 
 	oldGetenv := getenv
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{})
-	validHostnames = []string{tsURL.Hostname()}
 
 	base, err := tfc.parse(context.Background())
 	if err != nil {
@@ -1087,23 +1006,16 @@ func TestAWSCredential_RequestWithNoCredentialURL(t *testing.T) {
 func TestAWSCredential_RequestWithBadCredentialURL(t *testing.T) {
 	server := createDefaultAwsTestServer()
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 	server.WriteRolename = notFound
 
 	tfc := testFileConfig
 	tfc.CredentialSource = server.getCredentialSource(ts.URL)
 
 	oldGetenv := getenv
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{})
-	validHostnames = []string{tsURL.Hostname()}
 
 	base, err := tfc.parse(context.Background())
 	if err != nil {
@@ -1123,23 +1035,16 @@ func TestAWSCredential_RequestWithBadCredentialURL(t *testing.T) {
 func TestAWSCredential_RequestWithBadFinalCredentialURL(t *testing.T) {
 	server := createDefaultAwsTestServer()
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 	server.WriteSecurityCredentials = notFound
 
 	tfc := testFileConfig
 	tfc.CredentialSource = server.getCredentialSource(ts.URL)
 
 	oldGetenv := getenv
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{})
-	validHostnames = []string{tsURL.Hostname()}
 
 	base, err := tfc.parse(context.Background())
 	if err != nil {
@@ -1159,10 +1064,6 @@ func TestAWSCredential_RequestWithBadFinalCredentialURL(t *testing.T) {
 func TestAWSCredential_ShouldNotCallMetadataEndpointWhenCredsAreInEnv(t *testing.T) {
 	server := createDefaultAwsTestServer()
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 
 	metadataTs := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		t.Error("Metadata server should not have been called.")
@@ -1174,11 +1075,9 @@ func TestAWSCredential_ShouldNotCallMetadataEndpointWhenCredsAreInEnv(t *testing
 
 	oldGetenv := getenv
 	oldNow := now
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
 		now = oldNow
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{
 		"AWS_ACCESS_KEY_ID":     "AKIDEXAMPLE",
@@ -1186,7 +1085,6 @@ func TestAWSCredential_ShouldNotCallMetadataEndpointWhenCredsAreInEnv(t *testing
 		"AWS_REGION":            "us-west-1",
 	})
 	now = setTime(defaultTime)
-	validHostnames = []string{tsURL.Hostname()}
 
 	base, err := tfc.parse(context.Background())
 	if err != nil {
@@ -1214,28 +1112,21 @@ func TestAWSCredential_ShouldNotCallMetadataEndpointWhenCredsAreInEnv(t *testing
 func TestAWSCredential_ShouldCallMetadataEndpointWhenNoRegion(t *testing.T) {
 	server := createDefaultAwsTestServerWithImdsv2(t)
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 
 	tfc := testFileConfig
 	tfc.CredentialSource = server.getCredentialSource(ts.URL)
 
 	oldGetenv := getenv
 	oldNow := now
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
 		now = oldNow
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{
 		"AWS_ACCESS_KEY_ID":     accessKeyID,
 		"AWS_SECRET_ACCESS_KEY": secretAccessKey,
 	})
 	now = setTime(defaultTime)
-	validHostnames = []string{tsURL.Hostname()}
 
 	base, err := tfc.parse(context.Background())
 	if err != nil {
@@ -1263,28 +1154,21 @@ func TestAWSCredential_ShouldCallMetadataEndpointWhenNoRegion(t *testing.T) {
 func TestAWSCredential_ShouldCallMetadataEndpointWhenNoAccessKey(t *testing.T) {
 	server := createDefaultAwsTestServerWithImdsv2(t)
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 
 	tfc := testFileConfig
 	tfc.CredentialSource = server.getCredentialSource(ts.URL)
 
 	oldGetenv := getenv
 	oldNow := now
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
 		now = oldNow
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{
 		"AWS_SECRET_ACCESS_KEY": "wJalrXUtnFEMI/K7MDENG+bPxRfiCYEXAMPLEKEY",
 		"AWS_REGION":            "us-west-1",
 	})
 	now = setTime(defaultTime)
-	validHostnames = []string{tsURL.Hostname()}
 
 	base, err := tfc.parse(context.Background())
 	if err != nil {
@@ -1312,28 +1196,21 @@ func TestAWSCredential_ShouldCallMetadataEndpointWhenNoAccessKey(t *testing.T) {
 func TestAWSCredential_ShouldCallMetadataEndpointWhenNoSecretAccessKey(t *testing.T) {
 	server := createDefaultAwsTestServerWithImdsv2(t)
 	ts := httptest.NewServer(server)
-	tsURL, err := neturl.Parse(ts.URL)
-	if err != nil {
-		t.Fatalf("couldn't parse httptest servername")
-	}
 
 	tfc := testFileConfig
 	tfc.CredentialSource = server.getCredentialSource(ts.URL)
 
 	oldGetenv := getenv
 	oldNow := now
-	oldValidHostnames := validHostnames
 	defer func() {
 		getenv = oldGetenv
 		now = oldNow
-		validHostnames = oldValidHostnames
 	}()
 	getenv = setEnvironment(map[string]string{
 		"AWS_ACCESS_KEY_ID": "AKIDEXAMPLE",
 		"AWS_REGION":        "us-west-1",
 	})
 	now = setTime(defaultTime)
-	validHostnames = []string{tsURL.Hostname()}
 
 	base, err := tfc.parse(context.Background())
 	if err != nil {
@@ -1357,88 +1234,3 @@ func TestAWSCredential_ShouldCallMetadataEndpointWhenNoSecretAccessKey(t *testin
 		t.Errorf("subjectToken = \n%q\n want \n%q", got, want)
 	}
 }
-
-func TestAWSCredential_Validations(t *testing.T) {
-	var metadataServerValidityTests = []struct {
-		name       string
-		credSource CredentialSource
-		errText    string
-	}{
-		{
-			name: "No Metadata Server URLs",
-			credSource: CredentialSource{
-				EnvironmentID:         "aws1",
-				RegionURL:             "",
-				URL:                   "",
-				IMDSv2SessionTokenURL: "",
-			},
-		}, {
-			name: "IPv4 Metadata Server URLs",
-			credSource: CredentialSource{
-				EnvironmentID:         "aws1",
-				RegionURL:             "http://169.254.169.254/latest/meta-data/placement/availability-zone",
-				URL:                   "http://169.254.169.254/latest/meta-data/iam/security-credentials",
-				IMDSv2SessionTokenURL: "http://169.254.169.254/latest/api/token",
-			},
-		}, {
-			name: "IPv6 Metadata Server URLs",
-			credSource: CredentialSource{
-				EnvironmentID:         "aws1",
-				RegionURL:             "http://[fd00:ec2::254]/latest/meta-data/placement/availability-zone",
-				URL:                   "http://[fd00:ec2::254]/latest/meta-data/iam/security-credentials",
-				IMDSv2SessionTokenURL: "http://[fd00:ec2::254]/latest/api/token",
-			},
-		}, {
-			name: "Faulty RegionURL",
-			credSource: CredentialSource{
-				EnvironmentID:         "aws1",
-				RegionURL:             "http://abc.com/latest/meta-data/placement/availability-zone",
-				URL:                   "http://169.254.169.254/latest/meta-data/iam/security-credentials",
-				IMDSv2SessionTokenURL: "http://169.254.169.254/latest/api/token",
-			},
-			errText: "oauth2/google: invalid hostname http://abc.com/latest/meta-data/placement/availability-zone for region_url",
-		}, {
-			name: "Faulty CredVerificationURL",
-			credSource: CredentialSource{
-				EnvironmentID:         "aws1",
-				RegionURL:             "http://169.254.169.254/latest/meta-data/placement/availability-zone",
-				URL:                   "http://abc.com/latest/meta-data/iam/security-credentials",
-				IMDSv2SessionTokenURL: "http://169.254.169.254/latest/api/token",
-			},
-			errText: "oauth2/google: invalid hostname http://abc.com/latest/meta-data/iam/security-credentials for url",
-		}, {
-			name: "Faulty IMDSv2SessionTokenURL",
-			credSource: CredentialSource{
-				EnvironmentID:         "aws1",
-				RegionURL:             "http://169.254.169.254/latest/meta-data/placement/availability-zone",
-				URL:                   "http://169.254.169.254/latest/meta-data/iam/security-credentials",
-				IMDSv2SessionTokenURL: "http://abc.com/latest/api/token",
-			},
-			errText: "oauth2/google: invalid hostname http://abc.com/latest/api/token for imdsv2_session_token_url",
-		},
-	}
-
-	for _, tt := range metadataServerValidityTests {
-		t.Run(tt.name, func(t *testing.T) {
-			tfc := testFileConfig
-			tfc.CredentialSource = tt.credSource
-
-			oldGetenv := getenv
-			defer func() { getenv = oldGetenv }()
-			getenv = setEnvironment(map[string]string{})
-
-			_, err := tfc.parse(context.Background())
-			if err != nil {
-				if tt.errText == "" {
-					t.Errorf("Didn't expect an error, but got %v", err)
-				} else if tt.errText != err.Error() {
-					t.Errorf("Expected %v, but got %v", tt.errText, err)
-				}
-			} else {
-				if tt.errText != "" {
-					t.Errorf("Expected error %v, but got none", tt.errText)
-				}
-			}
-		})
-	}
-}

google/internal/externalaccount/basecredentials.go

@@ -185,10 +185,6 @@ func (c *Config) parse(ctx context.Context) (baseCredentialSource, error) {
 				awsCredSource.IMDSv2SessionTokenURL = c.CredentialSource.IMDSv2SessionTokenURL
 			}
 
-			if err := awsCredSource.validateMetadataServers(); err != nil {
-				return nil, err
-			}
-
 			return awsCredSource, nil
 		}
 	} else if c.CredentialSource.File != "" {