misc: small fix or general refactoring i did not bother commenting

modules/ble/ble_show.go

@@ -0,0 +1,288 @@
+// +build !windows
+// +build !darwin
+
+package ble
+
+import (
+	"fmt"
+	"os"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/bettercap/bettercap/network"
+
+	"github.com/bettercap/gatt"
+
+	"github.com/evilsocket/islazy/tui"
+)
+
+var (
+	bleAliveInterval   = time.Duration(5) * time.Second
+	blePresentInterval = time.Duration(30) * time.Second
+)
+
+func (mod *BLERecon) getRow(dev *network.BLEDevice) []string {
+	// ref. https://www.metageek.com/training/resources/understanding-rssi-2.html
+	rssi := fmt.Sprintf("%d dBm", dev.RSSI)
+	if dev.RSSI >= -67 {
+		rssi = tui.Green(rssi)
+	} else if dev.RSSI >= -70 {
+		rssi = tui.Dim(tui.Green(rssi))
+	} else if dev.RSSI >= -80 {
+		rssi = tui.Yellow(rssi)
+	} else {
+		rssi = tui.Dim(tui.Red(rssi))
+	}
+
+	address := network.NormalizeMac(dev.Device.ID())
+	vendor := tui.Dim(dev.Vendor)
+	sinceSeen := time.Since(dev.LastSeen)
+	lastSeen := dev.LastSeen.Format("15:04:05")
+
+	if sinceSeen <= bleAliveInterval {
+		lastSeen = tui.Bold(lastSeen)
+	} else if sinceSeen > blePresentInterval {
+		lastSeen = tui.Dim(lastSeen)
+		address = tui.Dim(address)
+	}
+
+	isConnectable := tui.Red("✖")
+	if dev.Advertisement.Connectable {
+		isConnectable = tui.Green("✔")
+	}
+
+	return []string{
+		rssi,
+		address,
+		dev.Device.Name(),
+		vendor,
+		isConnectable,
+		lastSeen,
+	}
+}
+
+func (mod *BLERecon) doFilter(dev *network.BLEDevice) bool {
+	if mod.selector.Expression == nil {
+		return true
+	}
+	return mod.selector.Expression.MatchString(dev.Device.ID()) ||
+		mod.selector.Expression.MatchString(dev.Device.Name()) ||
+		mod.selector.Expression.MatchString(dev.Vendor)
+}
+
+func (mod *BLERecon) doSelection() (err error, devices []*network.BLEDevice) {
+	if err = mod.selector.Update(); err != nil {
+		return
+	}
+
+	devices = mod.Session.BLE.Devices()
+	filtered := []*network.BLEDevice{}
+	for _, dev := range devices {
+		if mod.doFilter(dev) {
+			filtered = append(filtered, dev)
+		}
+	}
+	devices = filtered
+
+	switch mod.selector.SortField {
+	case "mac":
+		sort.Sort(ByBLEMacSorter(devices))
+	case "seen":
+		sort.Sort(ByBLESeenSorter(devices))
+	default:
+		sort.Sort(ByBLERSSISorter(devices))
+	}
+
+	// default is asc
+	if mod.selector.Sort == "desc" {
+		// from https://github.com/golang/go/wiki/SliceTricks
+		for i := len(devices)/2 - 1; i >= 0; i-- {
+			opp := len(devices) - 1 - i
+			devices[i], devices[opp] = devices[opp], devices[i]
+		}
+	}
+
+	if mod.selector.Limit > 0 {
+		limit := mod.selector.Limit
+		max := len(devices)
+		if limit > max {
+			limit = max
+		}
+		devices = devices[0:limit]
+	}
+
+	return
+}
+
+func (mod *BLERecon) colNames() []string {
+	colNames := []string{"RSSI", "MAC", "Name", "Vendor", "Connectable", "Seen"}
+	switch mod.selector.SortField {
+	case "rssi":
+		colNames[0] += " " + mod.selector.SortSymbol
+	case "mac":
+		colNames[1] += " " + mod.selector.SortSymbol
+	case "seen":
+		colNames[5] += " " + mod.selector.SortSymbol
+	}
+	return colNames
+}
+
+func (mod *BLERecon) Show() error {
+	err, devices := mod.doSelection()
+	if err != nil {
+		return err
+	}
+
+	rows := make([][]string, 0)
+	for _, dev := range devices {
+		rows = append(rows, mod.getRow(dev))
+	}
+
+	if len(rows) > 0 {
+		tui.Table(os.Stdout, mod.colNames(), rows)
+		mod.Session.Refresh()
+	}
+
+	return nil
+}
+
+func parseProperties(ch *gatt.Characteristic) (props []string, isReadable bool, isWritable bool, withResponse bool) {
+	isReadable = false
+	isWritable = false
+	withResponse = false
+	props = make([]string, 0)
+	mask := ch.Properties()
+
+	if (mask & gatt.CharBroadcast) != 0 {
+		props = append(props, "bcast")
+	}
+	if (mask & gatt.CharRead) != 0 {
+		isReadable = true
+		props = append(props, "read")
+	}
+	if (mask&gatt.CharWriteNR) != 0 || (mask&gatt.CharWrite) != 0 {
+		props = append(props, tui.Bold("write"))
+		isWritable = true
+		withResponse = (mask & gatt.CharWriteNR) == 0
+	}
+	if (mask & gatt.CharNotify) != 0 {
+		props = append(props, "notify")
+	}
+	if (mask & gatt.CharIndicate) != 0 {
+		props = append(props, "indicate")
+	}
+	if (mask & gatt.CharSignedWrite) != 0 {
+		props = append(props, tui.Yellow("*write"))
+		isWritable = true
+		withResponse = true
+	}
+	if (mask & gatt.CharExtended) != 0 {
+		props = append(props, "x")
+	}
+
+	return
+}
+
+func parseRawData(raw []byte) string {
+	s := ""
+	for _, b := range raw {
+		if b != 00 && !strconv.IsPrint(rune(b)) {
+			return fmt.Sprintf("%x", raw)
+		} else if b == 0 {
+			break
+		} else {
+			s += fmt.Sprintf("%c", b)
+		}
+	}
+
+	return tui.Yellow(s)
+}
+
+func (mod *BLERecon) showServices(p gatt.Peripheral, services []*gatt.Service) {
+	columns := []string{"Handles", "Service > Characteristics", "Properties", "Data"}
+	rows := make([][]string, 0)
+
+	wantsToWrite := mod.writeUUID != nil
+	foundToWrite := false
+
+	for _, svc := range services {
+		mod.Session.Events.Add("ble.device.service.discovered", svc)
+
+		name := svc.Name()
+		if name == "" {
+			name = svc.UUID().String()
+		} else {
+			name = fmt.Sprintf("%s (%s)", tui.Green(name), tui.Dim(svc.UUID().String()))
+		}
+
+		row := []string{
+			fmt.Sprintf("%04x -> %04x", svc.Handle(), svc.EndHandle()),
+			name,
+			"",
+			"",
+		}
+
+		rows = append(rows, row)
+
+		chars, err := p.DiscoverCharacteristics(nil, svc)
+		if err != nil {
+			mod.Error("error while enumerating chars for service %s: %s", svc.UUID(), err)
+			continue
+		}
+
+		for _, ch := range chars {
+			mod.Session.Events.Add("ble.device.characteristic.discovered", ch)
+
+			name = ch.Name()
+			if name == "" {
+				name = "    " + ch.UUID().String()
+			} else {
+				name = fmt.Sprintf("    %s (%s)", tui.Green(name), tui.Dim(ch.UUID().String()))
+			}
+
+			props, isReadable, isWritable, withResponse := parseProperties(ch)
+
+			if wantsToWrite && mod.writeUUID.Equal(ch.UUID()) {
+				foundToWrite = true
+				if isWritable {
+					mod.Info("writing %d bytes to characteristics %s ...", len(mod.writeData), mod.writeUUID)
+				} else {
+					mod.Warning("attempt to write %d bytes to non writable characteristics %s ...", len(mod.writeData), mod.writeUUID)
+				}
+
+				err := p.WriteCharacteristic(ch, mod.writeData, !withResponse)
+				if err != nil {
+					mod.Error("error while writing: %s", err)
+				}
+			}
+
+			data := ""
+			if isReadable {
+				raw, err := p.ReadCharacteristic(ch)
+				if err != nil {
+					data = tui.Red(err.Error())
+				} else {
+					data = parseRawData(raw)
+				}
+			}
+
+			row := []string{
+				fmt.Sprintf("%04x", ch.Handle()),
+				name,
+				strings.Join(props, ", "),
+				data,
+			}
+
+			rows = append(rows, row)
+		}
+	}
+
+	if wantsToWrite && !foundToWrite {
+		mod.Error("writable characteristics %s not found.", mod.writeUUID)
+	} else {
+		tui.Table(os.Stdout, columns, rows)
+		mod.Session.Refresh()
+	}
+}