[client] Add excluded port range handling for PKCE flow (#4853)

client/internal/auth/pkce_flow_windows_test.go

@@ -0,0 +1,116 @@
+//go:build windows
+
+package auth
+
+import (
+	"fmt"
+	"net"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/netbirdio/netbird/client/internal"
+)
+
+func TestParseExcludedPortRanges(t *testing.T) {
+	tests := []struct {
+		name           string
+		netshOutput    string
+		expectedRanges []excludedPortRange
+		expectError    bool
+	}{
+		{
+			name: "Valid netsh output with multiple ranges",
+			netshOutput: `
+Protocol tcp Dynamic Port Range
+---------------------------------
+Start Port      : 49152
+Number of Ports : 16384
+
+Protocol tcp Excluded Port Ranges
+---------------------------------
+Start Port    End Port
+----------    --------
+     5357        5357      *
+    50000       50059      *
+`,
+			expectedRanges: []excludedPortRange{
+				{start: 5357, end: 5357},
+				{start: 50000, end: 50059},
+			},
+			expectError: false,
+		},
+		{
+			name: "Empty output",
+			netshOutput: `
+Protocol tcp Dynamic Port Range
+---------------------------------
+Start Port      : 49152
+Number of Ports : 16384
+`,
+			expectedRanges: nil,
+			expectError:    false,
+		},
+		{
+			name: "Single range",
+			netshOutput: `
+Protocol tcp Excluded Port Ranges
+---------------------------------
+Start Port    End Port
+----------    --------
+     8080        8090
+`,
+			expectedRanges: []excludedPortRange{
+				{start: 8080, end: 8090},
+			},
+			expectError: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ranges, err := parseExcludedPortRanges(tt.netshOutput)
+
+			if tt.expectError {
+				assert.Error(t, err)
+			} else {
+				require.NoError(t, err)
+				assert.Equal(t, tt.expectedRanges, ranges)
+			}
+		})
+	}
+}
+
+func TestNewPKCEAuthorizationFlow_WithActualExcludedPorts(t *testing.T) {
+	ranges := getSystemExcludedPortRanges()
+	t.Logf("Found %d excluded port ranges on this system", len(ranges))
+
+	listener1, err := net.Listen("tcp", "127.0.0.1:0")
+	require.NoError(t, err)
+	defer func() {
+		_ = listener1.Close()
+	}()
+	usedPort1 := listener1.Addr().(*net.TCPAddr).Port
+
+	availablePort := 65432
+
+	config := internal.PKCEAuthProviderConfig{
+		ClientID:              "test-client-id",
+		Audience:              "test-audience",
+		TokenEndpoint:         "https://test-token-endpoint.com/token",
+		Scope:                 "openid email profile",
+		AuthorizationEndpoint: "https://test-auth-endpoint.com/authorize",
+		RedirectURLs: []string{
+			fmt.Sprintf("http://127.0.0.1:%d/", usedPort1),
+			fmt.Sprintf("http://127.0.0.1:%d/", availablePort),
+		},
+		UseIDToken: true,
+	}
+
+	flow, err := NewPKCEAuthorizationFlow(config)
+	require.NoError(t, err)
+	require.NotNil(t, flow)
+	assert.Contains(t, flow.oAuthConfig.RedirectURL, fmt.Sprintf(":%d", availablePort),
+		"Should skip port in use and select available port")
+}