feat(protonvpn): port forwarding support with NAT-PMP (#1543)

Co-authored-by: Nicholas Xavier <nicho@nicho.dev>

internal/natpmp/checks_test.go

@@ -0,0 +1,161 @@
+package natpmp
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_checkRequest(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		request    []byte
+		err        error
+		errMessage string
+	}{
+		"too_short": {
+			request:    []byte{1},
+			err:        ErrRequestSizeTooSmall,
+			errMessage: "message size is too small: need at least 2 bytes and got 1 byte(s)",
+		},
+		"success": {
+			request: []byte{0, 0},
+		},
+	}
+
+	for name, testCase := range testCases {
+		testCase := testCase
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			err := checkRequest(testCase.request)
+
+			assert.ErrorIs(t, err, testCase.err)
+			if testCase.err != nil {
+				assert.EqualError(t, err, testCase.errMessage)
+			}
+		})
+	}
+}
+
+func Test_checkResponse(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		response              []byte
+		expectedOperationCode byte
+		expectedResponseSize  uint
+		err                   error
+		errMessage            string
+	}{
+		"too_short": {
+			response:   []byte{1},
+			err:        ErrResponseSizeTooSmall,
+			errMessage: "response size is too small: need at least 4 bytes and got 1 byte(s)",
+		},
+		"size_mismatch": {
+			response:             []byte{0, 0, 0, 0},
+			expectedResponseSize: 5,
+			err:                  ErrResponseSizeUnexpected,
+			errMessage:           "response size is unexpected: expected 5 bytes and got 4 byte(s)",
+		},
+		"protocol_unknown": {
+			response:             []byte{1, 0, 0, 0},
+			expectedResponseSize: 4,
+			err:                  ErrProtocolVersionUnknown,
+			errMessage:           "protocol version is unknown: 1",
+		},
+		"operation_code_unexpected": {
+			response:              []byte{0, 2, 0, 0},
+			expectedOperationCode: 1,
+			expectedResponseSize:  4,
+			err:                   ErrOperationCodeUnexpected,
+			errMessage:            "operation code is unexpected: expected 0x1 and got 0x2",
+		},
+		"result_code_failure": {
+			response:              []byte{0, 1, 0, 1},
+			expectedOperationCode: 1,
+			expectedResponseSize:  4,
+			err:                   ErrVersionNotSupported,
+			errMessage:            "result code: version is not supported",
+		},
+		"success": {
+			response:              []byte{0, 1, 0, 0},
+			expectedOperationCode: 1,
+			expectedResponseSize:  4,
+		},
+	}
+
+	for name, testCase := range testCases {
+		testCase := testCase
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			err := checkResponse(testCase.response,
+				testCase.expectedOperationCode,
+				testCase.expectedResponseSize)
+
+			assert.ErrorIs(t, err, testCase.err)
+			if testCase.err != nil {
+				assert.EqualError(t, err, testCase.errMessage)
+			}
+		})
+	}
+}
+
+func Test_checkResultCode(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		resultCode uint16
+		err        error
+		errMessage string
+	}{
+		"success": {},
+		"version_unsupported": {
+			resultCode: 1,
+			err:        ErrVersionNotSupported,
+			errMessage: "version is not supported",
+		},
+		"not_authorized": {
+			resultCode: 2,
+			err:        ErrNotAuthorized,
+			errMessage: "not authorized",
+		},
+		"network_failure": {
+			resultCode: 3,
+			err:        ErrNetworkFailure,
+			errMessage: "network failure",
+		},
+		"out_of_resources": {
+			resultCode: 4,
+			err:        ErrOutOfResources,
+			errMessage: "out of resources",
+		},
+		"unsupported_operation_code": {
+			resultCode: 5,
+			err:        ErrOperationCodeNotSupported,
+			errMessage: "operation code is not supported",
+		},
+		"unknown": {
+			resultCode: 6,
+			err:        ErrResultCodeUnknown,
+			errMessage: "result code is unknown: 6",
+		},
+	}
+
+	for name, testCase := range testCases {
+		testCase := testCase
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			err := checkResultCode(testCase.resultCode)
+
+			assert.ErrorIs(t, err, testCase.err)
+			if testCase.err != nil {
+				assert.EqualError(t, err, testCase.errMessage)
+			}
+		})
+	}
+}