Fix EC2MetadataInstanceInfo ENI calculation

kubernetes-sigs · Jun 17, 2024 · 2e778b4 · 2e778b4
1 parent 73b4399
commit 2e778b4
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Showing 4 changed files with 49 additions and 7 deletions.
diff --git a/pkg/cloud/metadata/ec2.go b/pkg/cloud/metadata/ec2.go
@@ -88,7 +88,7 @@ func EC2MetadataInstanceInfo(svc EC2Metadata, regionFromSession string) (*Metada
 	if err != nil {
 		return nil, fmt.Errorf("could not read ENIs metadata content: %w", err)
 	}
-	attachedENIs := strings.Count(string(enis), "\n")
+	attachedENIs := util.CountMACAddresses(string(enis))
 
 	blockDevMappings := 0
 	if !util.IsSBE(doc.Region) {

diff --git a/pkg/cloud/metadata/metadata_test.go b/pkg/cloud/metadata/metadata_test.go
@@ -115,7 +115,7 @@ func TestNewMetadataService(t *testing.T) {
 					},
 				}, nil)
 				mockEC2Metadata.EXPECT().GetMetadata(gomock.Any(), &imds.GetMetadataInput{Path: EnisEndpoint}).Return(&imds.GetMetadataOutput{
-					Content: io.NopCloser(strings.NewReader("01:23:45:67:89:ab\n")),
+					Content: io.NopCloser(strings.NewReader("01:23:45:67:89:ab")),
 				}, nil)
 				mockEC2Metadata.EXPECT().GetMetadata(gomock.Any(), &imds.GetMetadataInput{Path: BlockDevicesEndpoint}).Return(&imds.GetMetadataOutput{
 					Content: io.NopCloser(strings.NewReader("ebs\nebs\n")),
@@ -257,7 +257,7 @@ func TestEC2MetadataInstanceInfo(t *testing.T) {
 					},
 				}, nil)
 				m.EXPECT().GetMetadata(gomock.Any(), &imds.GetMetadataInput{Path: EnisEndpoint}).Return(&imds.GetMetadataOutput{
-					Content: io.NopCloser(strings.NewReader("eni-1\neni-2\n")),
+					Content: io.NopCloser(strings.NewReader("eni-1\neni-2")),
 				}, nil)
 				m.EXPECT().GetMetadata(gomock.Any(), &imds.GetMetadataInput{Path: BlockDevicesEndpoint}).Return(nil, errors.New("failed to get block device mappings metadata"))
 			},
@@ -275,7 +275,7 @@ func TestEC2MetadataInstanceInfo(t *testing.T) {
 					},
 				}, nil)
 				m.EXPECT().GetMetadata(gomock.Any(), &imds.GetMetadataInput{Path: EnisEndpoint}).Return(&imds.GetMetadataOutput{
-					Content: io.NopCloser(strings.NewReader("eni-1\neni-2\n")),
+					Content: io.NopCloser(strings.NewReader("01:23:45:67:89:ab\n02:23:45:67:89:ab")),
 				}, nil)
 				m.EXPECT().GetMetadata(gomock.Any(), &imds.GetMetadataInput{Path: BlockDevicesEndpoint}).Return(&imds.GetMetadataOutput{
 					Content: io.NopCloser(errReader{}),
@@ -295,7 +295,7 @@ func TestEC2MetadataInstanceInfo(t *testing.T) {
 					},
 				}, nil)
 				m.EXPECT().GetMetadata(gomock.Any(), &imds.GetMetadataInput{Path: EnisEndpoint}).Return(&imds.GetMetadataOutput{
-					Content: io.NopCloser(strings.NewReader("eni-1\neni-2\n")),
+					Content: io.NopCloser(strings.NewReader("01:23:45:67:89:ab\n02:23:45:67:89:ab")),
 				}, nil)
 				m.EXPECT().GetMetadata(gomock.Any(), &imds.GetMetadataInput{Path: BlockDevicesEndpoint}).Return(&imds.GetMetadataOutput{
 					Content: io.NopCloser(strings.NewReader("ebs\nebs\n")),
@@ -332,7 +332,7 @@ func TestEC2MetadataInstanceInfo(t *testing.T) {
 					},
 				}, nil)
 				m.EXPECT().GetMetadata(gomock.Any(), &imds.GetMetadataInput{Path: EnisEndpoint}).Return(&imds.GetMetadataOutput{
-					Content: io.NopCloser(strings.NewReader("eni-1\neni-2\n")),
+					Content: io.NopCloser(strings.NewReader("01:23:45:67:89:ab\n02:23:45:67:89:ab")),
 				}, nil)
 				m.EXPECT().GetMetadata(gomock.Any(), &imds.GetMetadataInput{Path: BlockDevicesEndpoint}).Return(&imds.GetMetadataOutput{
 					Content: io.NopCloser(strings.NewReader("ebs\nebs\n")),
@@ -362,7 +362,7 @@ func TestEC2MetadataInstanceInfo(t *testing.T) {
 					},
 				}, nil)
 				m.EXPECT().GetMetadata(gomock.Any(), &imds.GetMetadataInput{Path: EnisEndpoint}).Return(&imds.GetMetadataOutput{
-					Content: io.NopCloser(strings.NewReader("eni-1\neni-2\n")),
+					Content: io.NopCloser(strings.NewReader("01:23:45:67:89:ab\n02:23:45:67:89:ab")),
 				}, nil)
 				m.EXPECT().GetMetadata(gomock.Any(), &imds.GetMetadataInput{Path: OutpostArnEndpoint}).Return(nil, errors.New("404 - Not Found"))
 			},

diff --git a/pkg/util/util.go b/pkg/util/util.go
@@ -37,6 +37,7 @@ const (
 
 var (
 	isAlphanumericRegex = regexp.MustCompile(`^[a-zA-Z0-9]*$`).MatchString
+	isMACAddressRegex   = regexp.MustCompile(`(?s)([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})(.*?)`)
 )
 
 // RoundUpBytes rounds up the volume size in bytes up to multiplications of GiB
@@ -137,6 +138,12 @@ func StringIsAlphanumeric(s string) bool {
 	return isAlphanumericRegex(s)
 }
 
+// CountMACAddresses returns the amount of MAC addresses within a string
+func CountMACAddresses(s string) int {
+	matches := isMACAddressRegex.FindAllStringIndex(s, -1)
+	return len(matches)
+}
+
 // NormalizeWindowsPath normalizes a Windows path
 func NormalizeWindowsPath(path string) string {
 	normalizedPath := strings.Replace(path, "/", "\\", -1)

diff --git a/pkg/util/util_test.go b/pkg/util/util_test.go
@@ -185,6 +185,41 @@ func TestIsAlphanumeric(t *testing.T) {
 	}
 }
 
+func TestCountMACAddresses(t *testing.T) {
+	testCases := []struct {
+		name       string
+		testString string
+		expResult  int
+	}{
+		{
+			name:       "success with newline at end",
+			testString: "0e:1c:7d:81:2b:19/\n0e:8c:22:a2:16:ef/\n",
+			expResult:  2,
+		},
+		{
+			name:       "success with no newline",
+			testString: "0e:1c:7d:81:2b:19/\n0e:8c:22:a2:16:ef/sh-4.2$",
+			expResult:  2,
+		},
+		{
+			name:       "success with no addresses",
+			testString: "00:::00/sh-4.2$",
+			expResult:  0,
+		},
+		{
+			name:       "success with hard case",
+			testString: "Zé:1c:7d:81:2b:19/\n23:123:22:a2:16:ef/ff\n:/:sh-4.2$",
+			expResult:  0,
+		},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			res := CountMACAddresses(tc.testString)
+			assert.Equalf(t, tc.expResult, res, "Wrong value returned for CountMACAddresses. Expected %d for string %s, got %d", tc.expResult, tc.testString, res)
+		})
+	}
+}
+
 type TestRequest struct {
 	Name    string
 	Secrets map[string]string