package tui import ( "fmt" "strconv" "strings" "telephony-inspector/internal/capture" "telephony-inspector/internal/config" "telephony-inspector/internal/sip" internalSSH "telephony-inspector/internal/ssh" "github.com/charmbracelet/bubbles/list" "github.com/charmbracelet/bubbles/textinput" tea "github.com/charmbracelet/bubbletea" "github.com/charmbracelet/lipgloss" ) // View represents the current screen in the TUI type View int const ( ViewDashboard View = iota ViewCapture ViewAnalysis ViewNetworkMap ) // SubView for modal states type SubView int const ( SubViewNone SubView = iota SubViewSSHConfig SubViewAddNode SubViewCallDetail SubViewCaptureMenu SubViewFileBrowser ) // CaptureMode defines local vs SSH capture type CaptureMode int const ( CaptureModeNone CaptureMode = iota CaptureModeLocal CaptureModeSSH ) // Model holds the application state type Model struct { currentView View subView SubView width int height int // Network map configuration networkMap *config.NetworkMap // Capture state captureMode CaptureMode sshConfig SSHConfigModel capturer *capture.Capturer localCapturer *capture.LocalCapturer connected bool capturing bool packetCount int lastPackets []string captureError string captureIface string // Call flow analysis callFlowStore *sip.CallFlowStore selectedFlow int flowList list.Model // File browser for pcap import fileBrowser FileBrowserModel loadedPcapPath string // Network node input nodeInput []textinput.Model nodeInputFocus int // Style definitions styles Styles } // Styles holds the lipgloss styles for the TUI type Styles struct { Title lipgloss.Style Subtitle lipgloss.Style Active lipgloss.Style Inactive lipgloss.Style Help lipgloss.Style StatusBar lipgloss.Style Error lipgloss.Style Success lipgloss.Style Box lipgloss.Style PacketRow lipgloss.Style CallFlow lipgloss.Style } func defaultStyles() Styles { return Styles{ Title: lipgloss.NewStyle(). Bold(true). Foreground(lipgloss.Color("#7D56F4")). MarginBottom(1), Subtitle: lipgloss.NewStyle(). Foreground(lipgloss.Color("#AFAFAF")), Active: lipgloss.NewStyle(). Bold(true). Foreground(lipgloss.Color("#04B575")), Inactive: lipgloss.NewStyle(). Foreground(lipgloss.Color("#626262")), Help: lipgloss.NewStyle(). Foreground(lipgloss.Color("#626262")). MarginTop(1), StatusBar: lipgloss.NewStyle(). Background(lipgloss.Color("#7D56F4")). Foreground(lipgloss.Color("#FFFFFF")). Padding(0, 1), Error: lipgloss.NewStyle(). Foreground(lipgloss.Color("#FF5555")), Success: lipgloss.NewStyle(). Foreground(lipgloss.Color("#50FA7B")), Box: lipgloss.NewStyle(). Border(lipgloss.RoundedBorder()). BorderForeground(lipgloss.Color("#7D56F4")). Padding(1, 2), PacketRow: lipgloss.NewStyle(). Foreground(lipgloss.Color("#F8F8F2")), CallFlow: lipgloss.NewStyle(). Border(lipgloss.NormalBorder()). BorderForeground(lipgloss.Color("#44475A")). Padding(0, 1), } } // NewModel creates a new TUI model with default values func NewModel() Model { // Try to load existing network map nm, err := config.LoadNetworkMap(config.DefaultNetworkMapPath()) if err != nil { nm = config.NewNetworkMap() } return Model{ currentView: ViewDashboard, subView: SubViewNone, networkMap: nm, callFlowStore: sip.NewCallFlowStore(), lastPackets: make([]string, 0, 50), sshConfig: NewSSHConfigModel(), nodeInput: createNodeInputs(), styles: defaultStyles(), } } func createNodeInputs() []textinput.Model { inputs := make([]textinput.Model, 4) inputs[0] = textinput.New() inputs[0].Placeholder = "Node Name" inputs[0].Prompt = "Name: " inputs[0].CharLimit = 64 inputs[1] = textinput.New() inputs[1].Placeholder = "192.168.1.x" inputs[1].Prompt = "IP: " inputs[1].CharLimit = 45 inputs[2] = textinput.New() inputs[2].Placeholder = "PBX/Proxy/MediaServer/Gateway" inputs[2].Prompt = "Type: " inputs[2].CharLimit = 20 inputs[3] = textinput.New() inputs[3].Placeholder = "Optional description" inputs[3].Prompt = "Desc: " inputs[3].CharLimit = 256 return inputs } // Init initializes the model func (m Model) Init() tea.Cmd { return nil } // PacketMsg is sent when a new packet is received type PacketMsg struct { Packet *sip.Packet } // ErrorMsg is sent when an error occurs type ErrorMsg struct { Error error } // Update handles messages and updates the model func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) { var cmd tea.Cmd // Handle subview updates first if m.subView != SubViewNone { return m.updateSubView(msg) } switch msg := msg.(type) { case tea.KeyMsg: switch msg.String() { case "q", "ctrl+c": m.cleanup() return m, tea.Quit case "1": m.currentView = ViewDashboard case "2": m.currentView = ViewCapture case "3": m.currentView = ViewAnalysis case "4": m.currentView = ViewNetworkMap default: cmd = m.handleViewKeys(msg) } case tea.WindowSizeMsg: m.width = msg.Width m.height = msg.Height case PacketMsg: m.packetCount++ summary := formatPacketSummary(msg.Packet, m.networkMap) m.lastPackets = append(m.lastPackets, summary) if len(m.lastPackets) > 50 { m.lastPackets = m.lastPackets[1:] } m.callFlowStore.AddPacket(msg.Packet) case ErrorMsg: m.captureError = msg.Error.Error() } return m, cmd } func (m *Model) handleViewKeys(msg tea.KeyMsg) tea.Cmd { switch m.currentView { case ViewCapture: switch msg.String() { case "c": // Show capture mode menu if not capturing if !m.capturing && m.captureMode == CaptureModeNone { m.subView = SubViewCaptureMenu } case "l": // Start local capture directly if !m.capturing { m.captureMode = CaptureModeLocal m.captureIface = "any" return m.startLocalCapture() } case "r": // SSH remote capture if !m.capturing { m.subView = SubViewSSHConfig m.sshConfig = NewSSHConfigModel() return m.sshConfig.Init() } case "s": if m.capturing { m.stopCapture() } else if m.captureMode != CaptureModeNone { if m.captureMode == CaptureModeLocal { return m.startLocalCapture() } else if m.connected { return m.startSSHCapture() } } case "d": m.disconnect() } case ViewAnalysis: switch msg.String() { case "up", "k": if m.selectedFlow > 0 { m.selectedFlow-- } case "down", "j": flows := m.callFlowStore.GetRecentFlows(20) if m.selectedFlow < len(flows)-1 { m.selectedFlow++ } case "enter": m.subView = SubViewCallDetail } case ViewNetworkMap: switch msg.String() { case "a": m.subView = SubViewAddNode m.nodeInput = createNodeInputs() m.nodeInput[0].Focus() m.nodeInputFocus = 0 case "l": if nm, err := config.LoadNetworkMap(config.DefaultNetworkMapPath()); err == nil { m.networkMap = nm } case "s": config.SaveNetworkMap(m.networkMap, config.DefaultNetworkMapPath()) case "g": m.networkMap = config.CreateSampleNetworkMap() } } return nil } func (m *Model) updateSubView(msg tea.Msg) (tea.Model, tea.Cmd) { switch m.subView { case SubViewCaptureMenu: if keyMsg, ok := msg.(tea.KeyMsg); ok { switch keyMsg.String() { case "l", "1": m.captureMode = CaptureModeLocal m.captureIface = "any" m.subView = SubViewNone return m, m.startLocalCapture() case "r", "2": m.subView = SubViewSSHConfig m.sshConfig = NewSSHConfigModel() return m, m.sshConfig.Init() case "p", "3": // Open file browser for pcap m.fileBrowser = NewFileBrowser("", ".pcap") m.subView = SubViewFileBrowser return m, nil case "esc", "q": m.subView = SubViewNone } } return m, nil case SubViewFileBrowser: var cmd tea.Cmd m.fileBrowser, cmd = m.fileBrowser.Update(msg) if m.fileBrowser.IsSelected() { // Load the pcap file pcapPath := m.fileBrowser.GetSelectedFile() m.loadedPcapPath = pcapPath m.subView = SubViewNone // Load packets from pcap reader := capture.NewPcapReader(pcapPath) packets, err := reader.ReadAll() if err != nil { m.captureError = err.Error() } else { m.captureError = "" m.packetCount = len(packets) for _, pkt := range packets { m.callFlowStore.AddPacket(pkt) summary := formatPacketSummary(pkt, m.networkMap) m.lastPackets = append(m.lastPackets, summary) } } return m, nil } else if m.fileBrowser.IsCancelled() { m.subView = SubViewNone } return m, cmd case SubViewSSHConfig: var cmd tea.Cmd m.sshConfig, cmd = m.sshConfig.Update(msg) if m.sshConfig.IsSubmitted() { host, port, user, password := m.sshConfig.GetConfig() portInt, _ := strconv.Atoi(port) if portInt == 0 { portInt = 22 } cfg := internalSSH.Config{ Host: host, Port: portInt, User: user, Password: password, } m.capturer = capture.NewCapturer(cfg) if err := m.capturer.Connect(); err != nil { m.captureError = err.Error() } else { m.connected = true m.captureMode = CaptureModeSSH m.captureError = "" } m.subView = SubViewNone } else if m.sshConfig.IsCancelled() { m.subView = SubViewNone } return m, cmd case SubViewAddNode: return m.updateNodeInput(msg) case SubViewCallDetail: if keyMsg, ok := msg.(tea.KeyMsg); ok { if keyMsg.String() == "esc" || keyMsg.String() == "q" { m.subView = SubViewNone } } return m, nil } return m, nil } func (m *Model) updateNodeInput(msg tea.Msg) (tea.Model, tea.Cmd) { if keyMsg, ok := msg.(tea.KeyMsg); ok { switch keyMsg.String() { case "esc": m.subView = SubViewNone return m, nil case "tab", "down": m.nodeInput[m.nodeInputFocus].Blur() m.nodeInputFocus = (m.nodeInputFocus + 1) % len(m.nodeInput) return m, m.nodeInput[m.nodeInputFocus].Focus() case "shift+tab", "up": m.nodeInput[m.nodeInputFocus].Blur() m.nodeInputFocus-- if m.nodeInputFocus < 0 { m.nodeInputFocus = len(m.nodeInput) - 1 } return m, m.nodeInput[m.nodeInputFocus].Focus() case "enter": if m.nodeInputFocus == len(m.nodeInput)-1 { // Submit name := m.nodeInput[0].Value() ip := m.nodeInput[1].Value() nodeType := m.nodeInput[2].Value() desc := m.nodeInput[3].Value() if name != "" && ip != "" { m.networkMap.AddNode(config.NetworkNode{ Name: name, IP: ip, Type: config.NodeType(nodeType), Description: desc, }) } m.subView = SubViewNone return m, nil } m.nodeInput[m.nodeInputFocus].Blur() m.nodeInputFocus++ return m, m.nodeInput[m.nodeInputFocus].Focus() } } var cmd tea.Cmd m.nodeInput[m.nodeInputFocus], cmd = m.nodeInput[m.nodeInputFocus].Update(msg) return m, cmd } func (m *Model) startLocalCapture() tea.Cmd { m.capturing = true m.captureError = "" m.packetCount = 0 m.lastPackets = m.lastPackets[:0] m.captureMode = CaptureModeLocal m.localCapturer = capture.NewLocalCapturer() m.localCapturer.OnPacket = func(p *sip.Packet) { // Note: In real implementation, use channel + tea.Cmd } m.localCapturer.OnError = func(err error) { m.captureError = err.Error() } iface := m.captureIface if iface == "" { iface = "any" } if err := m.localCapturer.Start(iface, 5060); err != nil { m.captureError = err.Error() m.capturing = false } return nil } func (m *Model) startSSHCapture() tea.Cmd { m.capturing = true m.captureError = "" m.packetCount = 0 m.lastPackets = m.lastPackets[:0] m.capturer.OnPacket = func(p *sip.Packet) { // Note: In real implementation, use channel + tea.Cmd } m.capturer.OnError = func(err error) { m.captureError = err.Error() } if err := m.capturer.Start("any", 5060); err != nil { m.captureError = err.Error() m.capturing = false } return nil } func (m *Model) stopCapture() { if m.localCapturer != nil { m.localCapturer.Stop() } if m.capturer != nil { m.capturer.Stop() } m.capturing = false } func (m *Model) disconnect() { m.stopCapture() if m.localCapturer != nil { m.localCapturer.Close() m.localCapturer = nil } if m.capturer != nil { m.capturer.Close() m.capturer = nil } m.connected = false m.captureMode = CaptureModeNone } func (m *Model) cleanup() { m.disconnect() } // View renders the TUI func (m Model) View() string { // Handle subview modals if m.subView != SubViewNone { return m.renderSubView() } var content string switch m.currentView { case ViewDashboard: content = m.viewDashboard() case ViewCapture: content = m.viewCapture() case ViewAnalysis: content = m.viewAnalysis() case ViewNetworkMap: content = m.viewNetworkMap() } nav := m.renderNav() status := m.renderStatusBar() return lipgloss.JoinVertical(lipgloss.Left, nav, content, status) } func (m Model) renderSubView() string { switch m.subView { case SubViewCaptureMenu: return m.styles.Box.Render(m.renderCaptureMenu()) case SubViewFileBrowser: return m.styles.Box.Render(m.fileBrowser.View()) case SubViewSSHConfig: return m.styles.Box.Render(m.sshConfig.View()) case SubViewAddNode: return m.styles.Box.Render(m.renderAddNodeForm()) case SubViewCallDetail: return m.renderCallDetail() } return "" } func (m Model) renderCaptureMenu() string { var b strings.Builder b.WriteString(m.styles.Title.Render("πŸ“‘ Select Capture Mode")) b.WriteString("\n\n") b.WriteString(" [1] [L]ocal - Capture on this machine (requires tcpdump)\n") b.WriteString(" [2] [R]emote - Capture via SSH on remote server\n") b.WriteString(" [3] [P]cap - Import pcap file from disk\n") b.WriteString("\n") b.WriteString(m.styles.Help.Render("Press 1/L, 2/R, or 3/P to select β€’ Esc to cancel")) return b.String() } func (m Model) renderAddNodeForm() string { var b strings.Builder b.WriteString(m.styles.Title.Render("βž• Add Network Node")) b.WriteString("\n\n") for _, input := range m.nodeInput { b.WriteString(input.View()) b.WriteString("\n") } b.WriteString("\n") b.WriteString(m.styles.Help.Render("Tab navigate β€’ Enter submit β€’ Esc cancel")) return b.String() } func (m Model) renderCallDetail() string { flows := m.callFlowStore.GetRecentFlows(20) if m.selectedFlow >= len(flows) || len(flows) == 0 { return m.styles.Box.Render("No call selected\n\nPress Esc to go back") } flow := flows[m.selectedFlow] var b strings.Builder b.WriteString(m.styles.Title.Render("πŸ“ž Call Detail")) b.WriteString("\n\n") b.WriteString(fmt.Sprintf("Call-ID: %s\n", flow.CallID)) b.WriteString(fmt.Sprintf("From: %s\n", flow.From)) b.WriteString(fmt.Sprintf("To: %s\n", flow.To)) b.WriteString(fmt.Sprintf("State: %s\n", flow.State)) b.WriteString(fmt.Sprintf("Packets: %d\n\n", len(flow.Packets))) b.WriteString("Transaction Flow:\n") for i, pkt := range flow.Packets { arrow := "β†’" if !pkt.IsRequest { arrow = "←" } // Format timestamp ts := pkt.Timestamp.Format("15:04:05.000") // Detailed packet info line b.WriteString(fmt.Sprintf(" %d. [%s] %s %s %s:%d -> %s:%d\n", i+1, ts, arrow, pkt.Summary(), pkt.SourceIP, pkt.SourcePort, pkt.DestIP, pkt.DestPort)) // Show SDP info if present if pkt.SDP != nil { mediaIP := pkt.SDP.GetSDPMediaIP() if mediaIP != "" { label := m.networkMap.LabelForIP(mediaIP) b.WriteString(fmt.Sprintf(" SDP Media: %s (%s)\n", mediaIP, label)) } } } b.WriteString("\n") b.WriteString(m.styles.Help.Render("Press Esc to go back")) return m.styles.Box.Render(b.String()) } func (m Model) renderNav() string { tabs := []string{"[1] Dashboard", "[2] Capture", "[3] Analysis", "[4] Network Map"} // Calculate tab width for even distribution tabWidth := m.width / len(tabs) if tabWidth < 15 { tabWidth = 15 } // Style for active and inactive tabs with fixed width activeStyle := lipgloss.NewStyle(). Bold(true). Foreground(lipgloss.Color("#FFFFFF")). Background(lipgloss.Color("#7D56F4")). Width(tabWidth). Align(lipgloss.Center) inactiveStyle := lipgloss.NewStyle(). Foreground(lipgloss.Color("#AFAFAF")). Background(lipgloss.Color("#282A36")). Width(tabWidth). Align(lipgloss.Center) var rendered []string for i, tab := range tabs { if View(i) == m.currentView { rendered = append(rendered, activeStyle.Render(tab)) } else { rendered = append(rendered, inactiveStyle.Render(tab)) } } // Join tabs and add background bar navBar := lipgloss.JoinHorizontal(lipgloss.Top, rendered...) // Fill remaining width with background barStyle := lipgloss.NewStyle(). Background(lipgloss.Color("#282A36")). Width(m.width) return barStyle.Render(navBar) + "\n" } func (m Model) renderStatusBar() string { var parts []string parts = append(parts, " Telephony Inspector v0.1.0 ") if m.connected { parts = append(parts, m.styles.Success.Render(" SSH: Connected ")) } if m.capturing { parts = append(parts, m.styles.Active.Render(fmt.Sprintf(" Capturing: %d pkts ", m.packetCount))) } if m.captureError != "" { parts = append(parts, m.styles.Error.Render(" Error: "+m.captureError+" ")) } return m.styles.StatusBar.Render(strings.Join(parts, "|")) } func (m Model) viewDashboard() string { title := m.styles.Title.Render("πŸ“ž Dashboard") var stats []string stats = append(stats, m.styles.Subtitle.Render("SIP Telephony Inspector")) stats = append(stats, "") if m.connected { stats = append(stats, m.styles.Success.Render("βœ“ SSH Connected")) } else { stats = append(stats, m.styles.Inactive.Render("β—‹ SSH Disconnected")) } stats = append(stats, fmt.Sprintf("Network Nodes: %d", len(m.networkMap.Nodes))) stats = append(stats, fmt.Sprintf("Active Calls: %d", m.callFlowStore.Count())) stats = append(stats, fmt.Sprintf("Packets Captured: %d", m.packetCount)) stats = append(stats, "") stats = append(stats, "Quick Start:") stats = append(stats, " 1. Go to [2] Capture β†’ Press 'c' to connect SSH") stats = append(stats, " 2. Press 's' to start capturing SIP traffic") stats = append(stats, " 3. Go to [3] Analysis to view call flows") stats = append(stats, " 4. Go to [4] Network Map to label IPs") stats = append(stats, "") stats = append(stats, m.styles.Help.Render("Press 1-4 to navigate, q to quit")) return lipgloss.JoinVertical(lipgloss.Left, title, lipgloss.JoinVertical(lipgloss.Left, stats...)) } func (m Model) viewCapture() string { title := m.styles.Title.Render("πŸ” Capture") var lines []string // Mode indicator switch m.captureMode { case CaptureModeLocal: lines = append(lines, m.styles.Success.Render("● Mode: Local capture")) case CaptureModeSSH: if m.connected { lines = append(lines, m.styles.Success.Render("● Mode: SSH (connected)")) } else { lines = append(lines, m.styles.Inactive.Render("β—‹ Mode: SSH (disconnected)")) } default: lines = append(lines, m.styles.Inactive.Render("β—‹ No capture mode selected")) } // Capture status if m.capturing { mode := "local" if m.captureMode == CaptureModeSSH { mode = "SSH" } lines = append(lines, m.styles.Active.Render(fmt.Sprintf("● Capturing on port 5060 (%s)", mode))) } else if m.captureMode != CaptureModeNone { lines = append(lines, m.styles.Inactive.Render("β—‹ Capture stopped")) } lines = append(lines, fmt.Sprintf("Packets: %d", m.packetCount)) lines = append(lines, "") // Last packets if len(m.lastPackets) > 0 { lines = append(lines, "Recent Packets:") start := 0 if len(m.lastPackets) > 15 { start = len(m.lastPackets) - 15 } for _, pkt := range m.lastPackets[start:] { lines = append(lines, " "+pkt) } } lines = append(lines, "") // Help var help string if m.captureMode == CaptureModeNone { help = "[c] Choose mode [l] Local [r] Remote SSH [q] Quit" } else if !m.capturing { help = "[s] Start [c] Change mode [d] Disconnect [q] Quit" } else { help = "[s] Stop [d] Disconnect [q] Quit" } lines = append(lines, m.styles.Help.Render(help)) return lipgloss.JoinVertical(lipgloss.Left, title, lipgloss.JoinVertical(lipgloss.Left, lines...)) } func (m Model) viewAnalysis() string { title := m.styles.Title.Render("πŸ“Š Analysis") flows := m.callFlowStore.GetRecentFlows(20) if len(flows) == 0 { return lipgloss.JoinVertical(lipgloss.Left, title, "No calls captured yet.", "", "Start capturing on the Capture tab to see call flows here.", "", m.styles.Help.Render("Press 2 to go to Capture")) } var lines []string lines = append(lines, fmt.Sprintf("Calls: %d", len(flows))) lines = append(lines, "") for i, flow := range flows { prefix := " " style := m.styles.Inactive if i == m.selectedFlow { prefix = "β–Ά " style = m.styles.Active } stateIcon := "β—‹" switch flow.State { case sip.CallStateRinging: stateIcon = "◐" case sip.CallStateConnected: stateIcon = "●" case sip.CallStateTerminated: stateIcon = "β—―" case sip.CallStateFailed: stateIcon = "βœ•" } summary := fmt.Sprintf("%s%s %s β†’ %s [%d pkts]", prefix, stateIcon, truncate(extractUser(flow.From), 15), truncate(extractUser(flow.To), 15), len(flow.Packets)) lines = append(lines, style.Render(summary)) } lines = append(lines, "") lines = append(lines, m.styles.Help.Render("↑/↓ select β€’ Enter details β€’ q quit")) return lipgloss.JoinVertical(lipgloss.Left, title, lipgloss.JoinVertical(lipgloss.Left, lines...)) } func (m Model) viewNetworkMap() string { title := m.styles.Title.Render("πŸ—ΊοΈ Network Map") if len(m.networkMap.Nodes) == 0 { return lipgloss.JoinVertical(lipgloss.Left, title, "No network nodes configured.", "", "Add nodes to label IPs in your SIP infrastructure.", "", m.styles.Help.Render("[a] Add node [l] Load file [g] Generate sample")) } var lines []string for _, node := range m.networkMap.Nodes { icon := "β—‹" switch node.Type { case config.NodeTypePBX: icon = "☎" case config.NodeTypeProxy: icon = "⇄" case config.NodeTypeMediaServer: icon = "β™ͺ" case config.NodeTypeGateway: icon = "⬚" } line := fmt.Sprintf(" %s %s (%s): %s", icon, node.Name, node.Type, node.IP) if node.Description != "" { line += " - " + node.Description } lines = append(lines, line) } lines = append(lines, "") lines = append(lines, m.styles.Help.Render("[a] Add [s] Save [l] Load [g] Sample [q] Quit")) return lipgloss.JoinVertical(lipgloss.Left, title, lipgloss.JoinVertical(lipgloss.Left, lines...)) } // Helper functions func formatPacketSummary(p *sip.Packet, nm *config.NetworkMap) string { src := nm.LabelForIP(p.SourceIP) dst := nm.LabelForIP(p.DestIP) if p.IsRequest { return fmt.Sprintf("%s β†’ %s: %s", src, dst, p.Method) } return fmt.Sprintf("%s β†’ %s: %d %s", src, dst, p.StatusCode, p.StatusText) } func truncate(s string, max int) string { if len(s) <= max { return s } return s[:max-1] + "…" } func extractUser(sipAddr string) string { // Extract user from "Display Name" if idx := strings.Index(sipAddr, "= 0 { start := idx + 5 end := strings.Index(sipAddr[start:], "@") if end > 0 { return sipAddr[start : start+end] } } if idx := strings.Index(sipAddr, "sip:"); idx >= 0 { start := idx + 4 end := strings.Index(sipAddr[start:], "@") if end > 0 { return sipAddr[start : start+end] } } return sipAddr }