Support for Time-based One-time Passwords (TOTP) in SMS Communicator

2020-02-10 16:54:18 +01:00 · 2020-02-10 16:54:18 +01:00 · 0f0452a1c4
parent 249a9b29a0
commit 0f0452a1c4
24 changed files with 739 additions and 72 deletions
--- a/app/build.gradle
+++ b/app/build.gradle
@ -282,6 +282,9 @@ dependencies {

    implementation 'com.github.DavidProdinger:weekdays-selector:1.1.0'

+    implementation 'com.github.kenglxn.QRGen:android:2.6.0'
+    implementation 'com.eatthepath:java-otp:0.2.0'
+
    testImplementation "junit:junit:4.12"
    testImplementation "org.json:json:20190722"
    testImplementation "org.mockito:mockito-core:2.8.47"
--- a/app/src/main/java/info/nightscout/androidaps/Constants.java
+++ b/app/src/main/java/info/nightscout/androidaps/Constants.java
@ -87,4 +87,20 @@ public class Constants {
    public static final double STATS_RANGE_HIGH_MMOL = 10.0;


+    // One Time Password
+
+    /**
+     * Size of generated key for TOTP Authenticator token, in bits
+     * rfc6238 suggest at least 160 for SHA1 based TOTP, but it ts too weak
+     * with 512 generated QRCode to provision authenticator is too detailed
+     * 256 is chosen as both secure enough and small enough for easy-scannable QRCode
+     */
+    public static final int OTP_GENERATED_KEY_LENGTH_BITS = 256;
+
+    /**
+     * How many old TOTP tokens still accept.
+     * Each token is 30s valid, but copying and SMS transmision of it can take additional seconds,
+     * so we add leeway to still accept given amount of older tokens
+     */
+    public static final int OTP_ACCEPT_OLD_TOKENS_COUNT = 1;
 }
--- a/app/src/main/java/info/nightscout/androidaps/MainApp.java
+++ b/app/src/main/java/info/nightscout/androidaps/MainApp.java
@ -106,6 +106,7 @@ import info.nightscout.androidaps.services.Intents;
 import info.nightscout.androidaps.utils.ActivityMonitor;
 import info.nightscout.androidaps.utils.FabricPrivacy;
 import info.nightscout.androidaps.utils.LocaleHelper;
+import info.nightscout.androidaps.utils.OneTimePassword;
 import info.nightscout.androidaps.utils.SP;
 import info.nightscout.androidaps.utils.resources.ResourceHelper;
 import io.fabric.sdk.android.Fabric;
@ -137,6 +138,7 @@ public class MainApp extends DaggerApplication {
    @Inject FabricPrivacy fabricPrivacy;
    @Inject ResourceHelper resourceHelper;
    @Inject VersionCheckerUtils versionCheckersUtils;
+    @Inject OneTimePassword oneTimePassword;

    @Inject ActionsPlugin actionsPlugin;
    @Inject AutomationPlugin automationPlugin;
--- a/app/src/main/java/info/nightscout/androidaps/dependencyInjection/FragmentsModule.kt
+++ b/app/src/main/java/info/nightscout/androidaps/dependencyInjection/FragmentsModule.kt
@ -27,6 +27,8 @@ import info.nightscout.androidaps.plugins.general.nsclient.NSClientFragment
 import info.nightscout.androidaps.plugins.general.overview.OverviewFragment
 import info.nightscout.androidaps.plugins.general.overview.dialogs.EditQuickWizardDialog
 import info.nightscout.androidaps.plugins.general.smsCommunicator.SmsCommunicatorFragment
+import info.nightscout.androidaps.plugins.general.smsCommunicator.fragments.SmsCommunicatorLogFragment
+import info.nightscout.androidaps.plugins.general.smsCommunicator.fragments.SmsCommunicatorOtpFragment
 import info.nightscout.androidaps.plugins.general.tidepool.TidepoolFragment
 import info.nightscout.androidaps.plugins.profile.local.LocalProfileFragment
 import info.nightscout.androidaps.plugins.profile.ns.NSProfileFragment
@ -69,8 +71,9 @@ abstract class FragmentsModule {
    @ContributesAndroidInjector abstract fun contributesMedtronicFragment(): MedtronicFragment
    @ContributesAndroidInjector abstract fun contributesNSProfileFragment(): NSProfileFragment
    @ContributesAndroidInjector abstract fun contributesNSClientFragment(): NSClientFragment
-    @ContributesAndroidInjector
-    abstract fun contributesSmsCommunicatorFragment(): SmsCommunicatorFragment
+    @ContributesAndroidInjector abstract fun contributesSmsCommunicatorFragment(): SmsCommunicatorFragment
+    @ContributesAndroidInjector abstract fun contributesSmsCommunicatorLogFragment(): SmsCommunicatorLogFragment
+    @ContributesAndroidInjector abstract fun contributesSmsCommunicatorOtpFragment(): SmsCommunicatorOtpFragment

    @ContributesAndroidInjector abstract fun contributesTidepoolFragment(): TidepoolFragment
    @ContributesAndroidInjector abstract fun contributesTreatmentsFragment(): TreatmentsFragment
--- a/app/src/main/java/info/nightscout/androidaps/plugins/general/smsCommunicator/AuthRequest.kt
+++ b/app/src/main/java/info/nightscout/androidaps/plugins/general/smsCommunicator/AuthRequest.kt
@ -5,10 +5,12 @@ import info.nightscout.androidaps.R
 import info.nightscout.androidaps.logging.L
 import info.nightscout.androidaps.logging.StacktraceLoggerWrapper
 import info.nightscout.androidaps.utils.DateUtil
+import info.nightscout.androidaps.utils.OneTimePassword
+import info.nightscout.androidaps.utils.OneTimePasswordValidationResult
 import info.nightscout.androidaps.utils.resources.ResourceHelper
 import org.slf4j.LoggerFactory

-class AuthRequest internal constructor(val plugin: SmsCommunicatorPlugin, val resourceHelper: ResourceHelper, var requester: Sms, requestText: String, var confirmCode: String, val action: SmsAction) {
+class AuthRequest internal constructor(val plugin: SmsCommunicatorPlugin, val resourceHelper: ResourceHelper, val otp: OneTimePassword, var requester: Sms, requestText: String, var confirmCode: String, val action: SmsAction) {
    private val log = StacktraceLoggerWrapper.getLogger(L.SMS)

    private val date = DateUtil.now()
@ -18,12 +20,20 @@ class AuthRequest internal constructor(val plugin: SmsCommunicatorPlugin, val re
        plugin.sendSMS(Sms(requester.phoneNumber, requestText))
    }

+    private fun codeIsValid(toValidate: String) : Boolean {
+        if (otp.isEnabled()) {
+            return otp.checkOTP(toValidate) == OneTimePasswordValidationResult.OK
+        } else {
+            return confirmCode.equals(toValidate)
+        }
+    }
+
    fun action(codeReceived: String) {
        if (processed) {
            if (L.isEnabled(L.SMS)) log.debug("Already processed")
            return
        }
-        if (confirmCode != codeReceived) {
+        if (!codeIsValid(codeReceived)) {
            processed = true
            if (L.isEnabled(L.SMS)) log.debug("Wrong code")
            plugin.sendSMS(Sms(requester.phoneNumber, resourceHelper.gs(R.string.sms_wrongcode)))
--- a/app/src/main/java/info/nightscout/androidaps/plugins/general/smsCommunicator/SmsCommunicatorFragment.kt
+++ b/app/src/main/java/info/nightscout/androidaps/plugins/general/smsCommunicator/SmsCommunicatorFragment.kt
@ -4,75 +4,78 @@ import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
+import androidx.fragment.app.Fragment
+import androidx.fragment.app.FragmentTransaction
 import dagger.android.support.DaggerFragment
 import info.nightscout.androidaps.R
 import info.nightscout.androidaps.plugins.bus.RxBusWrapper
-import info.nightscout.androidaps.plugins.general.smsCommunicator.events.EventSmsCommunicatorUpdateGui
-import info.nightscout.androidaps.utils.DateUtil
+import info.nightscout.androidaps.plugins.general.smsCommunicator.fragments.SmsCommunicatorLogFragment
+import info.nightscout.androidaps.plugins.general.smsCommunicator.fragments.SmsCommunicatorOtpFragment
 import info.nightscout.androidaps.utils.FabricPrivacy
-import info.nightscout.androidaps.utils.HtmlHelper
-import info.nightscout.androidaps.utils.extensions.plusAssign
-import io.reactivex.android.schedulers.AndroidSchedulers
-import io.reactivex.disposables.CompositeDisposable
+import info.nightscout.androidaps.utils.OneTimePassword
+import info.nightscout.androidaps.utils.resources.ResourceHelper
 import kotlinx.android.synthetic.main.smscommunicator_fragment.*
-import java.util.*
 import javax.inject.Inject
-import kotlin.math.max

 class SmsCommunicatorFragment : DaggerFragment() {
-    @Inject lateinit var fabricPrivacy : FabricPrivacy
    @Inject lateinit var rxBus: RxBusWrapper
+    @Inject lateinit var resourceHelper: ResourceHelper
+    @Inject lateinit var fabricPrivacy: FabricPrivacy
+    @Inject lateinit var otp: OneTimePassword
    @Inject lateinit var smsCommunicatorPlugin: SmsCommunicatorPlugin

-    private val disposable = CompositeDisposable()

    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
                              savedInstanceState: Bundle?): View? {
        return inflater.inflate(R.layout.smscommunicator_fragment, container, false)
    }

+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+        super.onViewCreated(view, savedInstanceState)
+
+        smscomunicator_tab_log.setOnClickListener {
+            setFragment(SmsCommunicatorLogFragment())
+            setBackgroundColorOnSelected(it)
+        }
+        smscomunicator_tab_otp.setOnClickListener {
+            setFragment(SmsCommunicatorOtpFragment())
+            setBackgroundColorOnSelected(it)
+        }
+
+        setFragment(SmsCommunicatorLogFragment())
+        setBackgroundColorOnSelected(smscomunicator_tab_log)
+    }
+
    @Synchronized
    override fun onResume() {
        super.onResume()
-        disposable += rxBus
-            .toObservable(EventSmsCommunicatorUpdateGui::class.java)
-            .observeOn(AndroidSchedulers.mainThread())
-            .subscribe({ updateGui() }) { fabricPrivacy.logException(it) }
        updateGui()
    }

-    @Synchronized
-    override fun onPause() {
-        super.onPause()
-        disposable.clear()
-    }
-
    fun updateGui() {
-        class CustomComparator : Comparator<Sms> {
-            override fun compare(object1: Sms, object2: Sms): Int {
-                return (object1.date - object2.date).toInt()
+        if (otp.isEnabled()) {
+            smscomunicator_tab_otp.visibility = View.VISIBLE
+        } else {
+            if (smscomunicator_tab_otp.visibility != View.GONE) {
+                setFragment(SmsCommunicatorLogFragment())
+                setBackgroundColorOnSelected(smscomunicator_tab_log)
+                smscomunicator_tab_otp.visibility = View.GONE
            }
        }
-        Collections.sort(smsCommunicatorPlugin.messages, CustomComparator())
-        val messagesToShow = 40
-        val start = max(0, smsCommunicatorPlugin.messages.size - messagesToShow)
-        var logText = ""
-        for (x in start until smsCommunicatorPlugin.messages.size) {
-            val sms = smsCommunicatorPlugin.messages[x]
-            when {
-                sms.ignored  -> {
-                    logText += DateUtil.timeString(sms.date) + " &lt;&lt;&lt; " + "░ " + sms.phoneNumber + " <b>" + sms.text + "</b><br>"
-                }
-
-                sms.received -> {
-                    logText += DateUtil.timeString(sms.date) + " &lt;&lt;&lt; " + (if (sms.processed) "● " else "○ ") + sms.phoneNumber + " <b>" + sms.text + "</b><br>"
-                }
-
-                sms.sent     -> {
-                    logText += DateUtil.timeString(sms.date) + " &gt;&gt;&gt; " + (if (sms.processed) "● " else "○ ") + sms.phoneNumber + " <b>" + sms.text + "</b><br>"
-                }
-            }
-        }
-        smscommunicator_log?.text = HtmlHelper.fromHtml(logText)
    }
+
+    private fun setFragment(selectedFragment: Fragment) {
+        val ft = childFragmentManager.beginTransaction()
+        ft.replace(R.id.smscomunicator_fragment_container, selectedFragment)
+        ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN)
+        ft.addToBackStack(null)
+        ft.commit()
+    }
+
+    private fun setBackgroundColorOnSelected(selected: View) {
+        smscomunicator_tab_log.setBackgroundColor(resourceHelper.gc(R.color.defaultbackground))
+        smscomunicator_tab_otp.setBackgroundColor(resourceHelper.gc(R.color.defaultbackground))
+        selected.setBackgroundColor(resourceHelper.gc(R.color.tabBgColorSelected))
+    }
+
 }
--- a/app/src/main/java/info/nightscout/androidaps/plugins/general/smsCommunicator/SmsCommunicatorPlugin.kt
+++ b/app/src/main/java/info/nightscout/androidaps/plugins/general/smsCommunicator/SmsCommunicatorPlugin.kt
@ -56,7 +56,8 @@ class SmsCommunicatorPlugin @Inject constructor(
    private val activePlugin: ActivePluginProvider,
    private val commandQueue: CommandQueueProvider,
    private val loopPlugin: LoopPlugin,
-    private val iobCobCalculatorPlugin: IobCobCalculatorPlugin
+    private val iobCobCalculatorPlugin: IobCobCalculatorPlugin,
+    private var otp: OneTimePassword
 ) : PluginBase(PluginDescription()
    .mainType(PluginType.GENERAL)
    .fragmentClass(SmsCommunicatorFragment::class.java.name)
@ -354,7 +355,7 @@ class SmsCommunicatorPlugin @Inject constructor(
                    val passCode = generatePasscode()
                    val reply = String.format(resourceHelper.gs(R.string.smscommunicator_suspendreplywithcode), duration, passCode)
                    receivedSms.processed = true
-                    messageToConfirm = AuthRequest(this, resourceHelper, receivedSms, reply, passCode, object : SmsAction(duration) {
+                    messageToConfirm = AuthRequest(this, resourceHelper, otp, receivedSms, reply, passCode, object : SmsAction(duration) {
                        override fun run() {
                            commandQueue.cancelTempBasal(true, object : Callback() {
                                override fun run() {
@ -469,7 +470,7 @@ class SmsCommunicatorPlugin @Inject constructor(
                    val reply = String.format(resourceHelper.gs(R.string.smscommunicator_profilereplywithcode), list[pindex - 1], percentage, passCode)
                    receivedSms.processed = true
                    val finalPercentage = percentage
-                    messageToConfirm = AuthRequest(this, resourceHelper, receivedSms, reply, passCode, object : SmsAction(list[pindex - 1] as String, finalPercentage) {
+                    messageToConfirm = AuthRequest(this, resourceHelper, otp, receivedSms, reply, passCode, object : SmsAction(list[pindex - 1] as String, finalPercentage) {
                        override fun run() {
                            activePlugin.activeTreatments.doProfileSwitch(store, list[pindex - 1] as String, 0, finalPercentage, 0, DateUtil.now())
                            sendSMS(Sms(receivedSms.phoneNumber, resourceHelper.gs(R.string.profileswitchcreated)))
@ -486,7 +487,7 @@ class SmsCommunicatorPlugin @Inject constructor(
            val passCode = generatePasscode()
            val reply = String.format(resourceHelper.gs(R.string.smscommunicator_basalstopreplywithcode), passCode)
            receivedSms.processed = true
-            messageToConfirm = AuthRequest(this, resourceHelper, receivedSms, reply, passCode, object : SmsAction() {
+            messageToConfirm = AuthRequest(this, resourceHelper, otp, receivedSms, reply, passCode, object : SmsAction() {
                override fun run() {
                    commandQueue.cancelTempBasal(true, object : Callback() {
                        override fun run() {
@ -516,7 +517,7 @@ class SmsCommunicatorPlugin @Inject constructor(
                val passCode = generatePasscode()
                val reply = String.format(resourceHelper.gs(R.string.smscommunicator_basalpctreplywithcode), tempBasalPct, duration, passCode)
                receivedSms.processed = true
-                messageToConfirm = AuthRequest(this, resourceHelper, receivedSms, reply, passCode, object : SmsAction(tempBasalPct, duration) {
+                messageToConfirm = AuthRequest(this, resourceHelper, otp, receivedSms, reply, passCode, object : SmsAction(tempBasalPct, duration) {
                    override fun run() {
                        commandQueue.tempBasalPercent(anInteger(), secondInteger(), true, profile, object : Callback() {
                            override fun run() {
@ -548,7 +549,7 @@ class SmsCommunicatorPlugin @Inject constructor(
                val passCode = generatePasscode()
                val reply = String.format(resourceHelper.gs(R.string.smscommunicator_basalreplywithcode), tempBasal, duration, passCode)
                receivedSms.processed = true
-                messageToConfirm = AuthRequest(this, resourceHelper, receivedSms, reply, passCode, object : SmsAction(tempBasal, duration) {
+                messageToConfirm = AuthRequest(this, resourceHelper, otp, receivedSms, reply, passCode, object : SmsAction(tempBasal, duration) {
                    override fun run() {
                        commandQueue.tempBasalAbsolute(aDouble(), secondInteger(), true, profile, object : Callback() {
                            override fun run() {
@ -575,7 +576,7 @@ class SmsCommunicatorPlugin @Inject constructor(
            val passCode = generatePasscode()
            val reply = String.format(resourceHelper.gs(R.string.smscommunicator_extendedstopreplywithcode), passCode)
            receivedSms.processed = true
-            messageToConfirm = AuthRequest(this, resourceHelper, receivedSms, reply, passCode, object : SmsAction() {
+            messageToConfirm = AuthRequest(this, resourceHelper, otp, receivedSms, reply, passCode, object : SmsAction() {
                override fun run() {
                    commandQueue.cancelExtended(object : Callback() {
                        override fun run() {
@ -603,7 +604,7 @@ class SmsCommunicatorPlugin @Inject constructor(
                val passCode = generatePasscode()
                val reply = String.format(resourceHelper.gs(R.string.smscommunicator_extendedreplywithcode), extended, duration, passCode)
                receivedSms.processed = true
-                messageToConfirm = AuthRequest(this, resourceHelper, receivedSms, reply, passCode, object : SmsAction(extended, duration) {
+                messageToConfirm = AuthRequest(this, resourceHelper, otp, receivedSms, reply, passCode, object : SmsAction(extended, duration) {
                    override fun run() {
                        commandQueue.extendedBolus(aDouble(), secondInteger(), object : Callback() {
                            override fun run() {
@ -638,7 +639,7 @@ class SmsCommunicatorPlugin @Inject constructor(
            else
                String.format(resourceHelper.gs(R.string.smscommunicator_bolusreplywithcode), bolus, passCode)
            receivedSms.processed = true
-            messageToConfirm = AuthRequest(this, resourceHelper, receivedSms, reply, passCode, object : SmsAction(bolus) {
+            messageToConfirm = AuthRequest(this, resourceHelper, otp, receivedSms, reply, passCode, object : SmsAction(bolus) {
                override fun run() {
                    val detailedBolusInfo = DetailedBolusInfo()
                    detailedBolusInfo.insulin = aDouble()
@ -714,7 +715,7 @@ class SmsCommunicatorPlugin @Inject constructor(
            val passCode = generatePasscode()
            val reply = String.format(resourceHelper.gs(R.string.smscommunicator_carbsreplywithcode), grams, DateUtil.timeString(time), passCode)
            receivedSms.processed = true
-            messageToConfirm = AuthRequest(this, resourceHelper, receivedSms, reply, passCode, object : SmsAction(grams, time) {
+            messageToConfirm = AuthRequest(this, resourceHelper, otp, receivedSms, reply, passCode, object : SmsAction(grams, time) {
                override fun run() {
                    val detailedBolusInfo = DetailedBolusInfo()
                    detailedBolusInfo.carbs = anInteger().toDouble()
@ -746,7 +747,7 @@ class SmsCommunicatorPlugin @Inject constructor(
            val passCode = generatePasscode()
            val reply = String.format(resourceHelper.gs(R.string.smscommunicator_temptargetwithcode), splitted[1].toUpperCase(Locale.getDefault()), passCode)
            receivedSms.processed = true
-            messageToConfirm = AuthRequest(this, resourceHelper, receivedSms, reply, passCode, object : SmsAction() {
+            messageToConfirm = AuthRequest(this, resourceHelper, otp, receivedSms, reply, passCode, object : SmsAction() {
                override fun run() {
                    val units = profileFunction.getUnits()
                    var keyDuration = 0
@ -801,7 +802,7 @@ class SmsCommunicatorPlugin @Inject constructor(
            val passCode = generatePasscode()
            val reply = String.format(resourceHelper.gs(R.string.smscommunicator_temptargetcancel), passCode)
            receivedSms.processed = true
-            messageToConfirm = AuthRequest(this, resourceHelper, receivedSms, reply, passCode, object : SmsAction() {
+            messageToConfirm = AuthRequest(this, resourceHelper, otp, receivedSms, reply, passCode, object : SmsAction() {
                override fun run() {
                    val tempTarget = TempTarget()
                        .source(Source.USER)
@ -825,7 +826,7 @@ class SmsCommunicatorPlugin @Inject constructor(
            val passCode = generatePasscode()
            val reply = String.format(resourceHelper.gs(R.string.smscommunicator_stopsmswithcode), passCode)
            receivedSms.processed = true
-            messageToConfirm = AuthRequest(this, resourceHelper, receivedSms, reply, passCode, object : SmsAction() {
+            messageToConfirm = AuthRequest(this, resourceHelper, otp, receivedSms, reply, passCode, object : SmsAction() {
                override fun run() {
                    sp.putBoolean(R.string.key_smscommunicator_remotecommandsallowed, false)
                    val replyText = String.format(resourceHelper.gs(R.string.smscommunicator_stoppedsms))
@ -841,7 +842,7 @@ class SmsCommunicatorPlugin @Inject constructor(
            val passCode = generatePasscode()
            val reply = String.format(resourceHelper.gs(R.string.smscommunicator_calibrationreplywithcode), cal, passCode)
            receivedSms.processed = true
-            messageToConfirm = AuthRequest(this, resourceHelper, receivedSms, reply, passCode, object : SmsAction(cal) {
+            messageToConfirm = AuthRequest(this, resourceHelper, otp, receivedSms, reply, passCode, object : SmsAction(cal) {
                override fun run() {
                    val result = XdripCalibrations.sendIntent(aDouble)
                    if (result) sendSMSToAllNumbers(Sms(receivedSms.phoneNumber, resourceHelper.gs(R.string.smscommunicator_calibrationsent))) else sendSMS(Sms(receivedSms.phoneNumber, resourceHelper.gs(R.string.smscommunicator_calibrationfailed)))
@ -898,6 +899,12 @@ class SmsCommunicatorPlugin @Inject constructor(
    }

    private fun generatePasscode(): String {
+
+        if (otp.isEnabled()) {
+            // this not realy generate password - rather info to use Authenticator TOTP instead
+            return resourceHelper.gs(R.string.smscommunicator_code_from_authenticator_for, otp.name());
+        }
+
        val startChar1 = 'A'.toInt() // on iphone 1st char is uppercase :)
        var passCode = Character.toString((startChar1 + Math.random() * ('z' - 'a' + 1)).toChar())
        val startChar2: Int = if (Math.random() > 0.5) 'a'.toInt() else 'A'.toInt()
--- a/app/src/main/java/info/nightscout/androidaps/plugins/general/smsCommunicator/fragments/SmsCommunicatorLogFragment.kt
+++ b/app/src/main/java/info/nightscout/androidaps/plugins/general/smsCommunicator/fragments/SmsCommunicatorLogFragment.kt
@ -0,0 +1,80 @@
+package info.nightscout.androidaps.plugins.general.smsCommunicator.fragments
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import dagger.android.support.DaggerFragment
+import info.nightscout.androidaps.R
+import info.nightscout.androidaps.plugins.bus.RxBusWrapper
+import info.nightscout.androidaps.plugins.general.smsCommunicator.Sms
+import info.nightscout.androidaps.plugins.general.smsCommunicator.SmsCommunicatorPlugin
+import info.nightscout.androidaps.plugins.general.smsCommunicator.events.EventSmsCommunicatorUpdateGui
+import info.nightscout.androidaps.utils.DateUtil
+import info.nightscout.androidaps.utils.FabricPrivacy
+import info.nightscout.androidaps.utils.HtmlHelper
+import info.nightscout.androidaps.utils.extensions.plusAssign
+import io.reactivex.android.schedulers.AndroidSchedulers
+import io.reactivex.disposables.CompositeDisposable
+import kotlinx.android.synthetic.main.smscommunicator_fragment_log.*
+import java.util.*
+import javax.inject.Inject
+import kotlin.math.max
+
+class SmsCommunicatorLogFragment : DaggerFragment() {
+    @Inject lateinit var fabricPrivacy : FabricPrivacy
+    @Inject lateinit var rxBus: RxBusWrapper
+    @Inject lateinit var smsCommunicatorPlugin: SmsCommunicatorPlugin
+
+    private val disposable = CompositeDisposable()
+
+    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
+                              savedInstanceState: Bundle?): View? {
+        return inflater.inflate(R.layout.smscommunicator_fragment_log, container, false)
+    }
+
+    @Synchronized
+    override fun onResume() {
+        super.onResume()
+        disposable += rxBus
+            .toObservable(EventSmsCommunicatorUpdateGui::class.java)
+            .observeOn(AndroidSchedulers.mainThread())
+            .subscribe({ updateGui() }) { fabricPrivacy.logException(it) }
+        updateGui()
+    }
+
+    @Synchronized
+    override fun onPause() {
+        super.onPause()
+        disposable.clear()
+    }
+
+    fun updateGui() {
+        class CustomComparator : Comparator<Sms> {
+            override fun compare(object1: Sms, object2: Sms): Int {
+                return (object1.date - object2.date).toInt()
+            }
+        }
+        Collections.sort(smsCommunicatorPlugin.messages, CustomComparator())
+        val messagesToShow = 40
+        val start = max(0, smsCommunicatorPlugin.messages.size - messagesToShow)
+        var logText = ""
+        for (x in start until smsCommunicatorPlugin.messages.size) {
+            val sms = smsCommunicatorPlugin.messages[x]
+            when {
+                sms.ignored  -> {
+                    logText += DateUtil.timeString(sms.date) + " &lt;&lt;&lt; " + "░ " + sms.phoneNumber + " <b>" + sms.text + "</b><br>"
+                }
+
+                sms.received -> {
+                    logText += DateUtil.timeString(sms.date) + " &lt;&lt;&lt; " + (if (sms.processed) "● " else "○ ") + sms.phoneNumber + " <b>" + sms.text + "</b><br>"
+                }
+
+                sms.sent     -> {
+                    logText += DateUtil.timeString(sms.date) + " &gt;&gt;&gt; " + (if (sms.processed) "● " else "○ ") + sms.phoneNumber + " <b>" + sms.text + "</b><br>"
+                }
+            }
+        }
+        smscommunicator_log?.text = HtmlHelper.fromHtml(logText)
+    }
+}
--- a/app/src/main/java/info/nightscout/androidaps/plugins/general/smsCommunicator/fragments/SmsCommunicatorOtpFragment.kt
+++ b/app/src/main/java/info/nightscout/androidaps/plugins/general/smsCommunicator/fragments/SmsCommunicatorOtpFragment.kt
@ -0,0 +1,115 @@
+package info.nightscout.androidaps.plugins.general.smsCommunicator.fragments
+
+import android.app.Activity
+import android.content.res.Resources
+import android.graphics.Color
+import android.os.Bundle
+import android.text.Editable
+import android.text.TextWatcher
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import com.google.common.primitives.Ints.min
+import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel
+import dagger.android.support.DaggerFragment
+import info.nightscout.androidaps.R
+import info.nightscout.androidaps.plugins.bus.RxBusWrapper
+import info.nightscout.androidaps.plugins.general.smsCommunicator.SmsCommunicatorPlugin
+import info.nightscout.androidaps.utils.FabricPrivacy
+import info.nightscout.androidaps.utils.OKDialog
+import info.nightscout.androidaps.utils.OneTimePassword
+import info.nightscout.androidaps.utils.OneTimePasswordValidationResult
+import info.nightscout.androidaps.utils.ToastUtils
+import info.nightscout.androidaps.utils.resources.ResourceHelper
+import kotlinx.android.synthetic.main.smscommunicator_fragment_otp.*
+import net.glxn.qrgen.android.QRCode
+import javax.inject.Inject
+
+class SmsCommunicatorOtpFragment : DaggerFragment() {
+    @Inject lateinit var fabricPrivacy: FabricPrivacy
+    @Inject lateinit var rxBus: RxBusWrapper
+    @Inject lateinit var smsCommunicatorPlugin: SmsCommunicatorPlugin
+    @Inject lateinit var otp: OneTimePassword
+    @Inject lateinit var resourceHelper: ResourceHelper
+
+    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
+                              savedInstanceState: Bundle?): View? {
+        return inflater.inflate(R.layout.smscommunicator_fragment_otp, container, false)
+    }
+
+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+        super.onViewCreated(view, savedInstanceState)
+
+        smscommunicator_otp_verify_edit.addTextChangedListener(object : TextWatcher {
+            override fun afterTextChanged(s: Editable?) {
+                if (s != null) {
+                    val checkResult = otp.checkOTP(s.toString())
+
+                    smscommunicator_otp_verify_label.text = when (checkResult) {
+                        OneTimePasswordValidationResult.OK                 -> "OK"
+                        OneTimePasswordValidationResult.ERROR_WRONG_LENGTH -> "INVALID SIZE!"
+                        OneTimePasswordValidationResult.ERROR_WRONG_PIN    -> "WRONG PIN"
+                        OneTimePasswordValidationResult.ERROR_WRONG_OTP    -> "WRONG OTP"
+                    }
+
+                    smscommunicator_otp_verify_label.setTextColor(when (checkResult) {
+                        OneTimePasswordValidationResult.OK                 -> Color.GREEN
+                        OneTimePasswordValidationResult.ERROR_WRONG_LENGTH -> Color.YELLOW
+                        OneTimePasswordValidationResult.ERROR_WRONG_PIN    -> Color.RED
+                        OneTimePasswordValidationResult.ERROR_WRONG_OTP    -> Color.RED
+                    })
+
+                } else {
+                    smscommunicator_otp_verify_label.text = "EMPTY";
+                    smscommunicator_otp_verify_label.setTextColor(Color.YELLOW)
+                }
+            }
+
+            override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {
+            }
+
+            override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {
+            }
+        })
+
+        actions_smscommunicator_otp_reset.setOnClickListener {
+            if (this.activity != null) {
+                OKDialog.showConfirmation(this.activity!!,
+                    resourceHelper.gs(R.string.smscommunicator_otp_reset_title),
+                    resourceHelper.gs(R.string.smscommunicator_otp_reset_prompt),
+                    Runnable {
+                        otp.ensureKey(true)
+                        updateGui()
+                        ToastUtils.showToastInUiThread(this.context, R.string.smscommunicator_otp_reset_successful)
+                    })
+            }
+        }
+
+    }
+
+    @Synchronized
+    override fun onResume() {
+        super.onResume()
+        updateGui()
+    }
+
+    fun updateGui() {
+        val displayMetrics = Resources.getSystem().getDisplayMetrics()
+        val width = displayMetrics.widthPixels
+        val height = displayMetrics.heightPixels
+
+        // ensure QRCode is big enough to fit on screen
+        val dim = (min(width, height) * 0.85).toInt()
+        val provURI = otp.provisioningURI();
+
+        if (provURI != null) {
+            val myBitmap = QRCode.from(provURI).withErrorCorrection(ErrorCorrectionLevel.H).withSize(dim, dim).bitmap()
+            smscommunicator_otp_provisioning.setImageBitmap(myBitmap)
+            smscommunicator_otp_provisioning.visibility = View.VISIBLE
+        } else {
+            smscommunicator_otp_provisioning.visibility = View.GONE
+        }
+
+        smscommunicator_otp_verify_edit.text = smscommunicator_otp_verify_edit.text
+    }
+}
--- a/app/src/main/java/info/nightscout/androidaps/utils/OneTimePasswordValidationResult.kt
+++ b/app/src/main/java/info/nightscout/androidaps/utils/OneTimePasswordValidationResult.kt
@ -0,0 +1,8 @@
+package info.nightscout.androidaps.utils
+
+enum class OneTimePasswordValidationResult {
+    OK,
+    ERROR_WRONG_LENGTH,
+    ERROR_WRONG_PIN,
+    ERROR_WRONG_OTP
+}
--- a/app/src/main/java/info/nightscout/androidaps/utils/OneTimePasswords.kt
+++ b/app/src/main/java/info/nightscout/androidaps/utils/OneTimePasswords.kt
@ -0,0 +1,135 @@
+package info.nightscout.androidaps.utils
+
+import android.util.Base64
+import com.eatthepath.otp.TimeBasedOneTimePasswordGenerator
+import com.google.common.io.BaseEncoding
+import info.nightscout.androidaps.Constants
+import info.nightscout.androidaps.R
+import info.nightscout.androidaps.utils.resources.ResourceHelper
+import info.nightscout.androidaps.utils.sharedPreferences.SP
+import org.joda.time.DateTimeUtils
+import java.net.URLEncoder
+import javax.crypto.KeyGenerator
+import javax.crypto.SecretKey
+import javax.crypto.spec.SecretKeySpec
+import javax.inject.Inject
+import javax.inject.Singleton
+
+@Singleton
+class OneTimePassword @Inject constructor(
+    private val sp: SP,
+    private val resourceHelper: ResourceHelper
+) {
+
+    private var key: SecretKey? = null
+    private var pin: String = ""
+    private val totp = TimeBasedOneTimePasswordGenerator()
+
+    init {
+        instance = this
+        configure()
+    }
+
+    companion object {
+        private lateinit var instance: OneTimePassword
+        @JvmStatic
+        fun getInstance(): OneTimePassword = instance
+    }
+
+    /**
+     * If OTP Authenticator support is enabled by user
+     */
+    fun isEnabled(): Boolean {
+        return sp.getBoolean(R.string.key_smscommunicator_otp_enabled, false);
+    }
+
+    /**
+     * Name of master device (target of OTP)
+     */
+    fun name(): String {
+        val defaultUserName = resourceHelper.gs(R.string.smscommunicator_default_user_display_name)
+        var userName = sp.getString(R.string.key_smscommunicator_otp_name, defaultUserName).trim()
+        if (userName.length == 0)
+            userName = defaultUserName
+        return userName
+    }
+
+    /**
+     * Make sure if private key for TOTP is generated, creating it when necessary or requested
+     */
+    fun ensureKey(forceNewKey: Boolean = false) {
+        var keyBytes: ByteArray = byteArrayOf()
+        val strSecret = sp.getString(R.string.key_smscommunicator_otp_secret, "").trim()
+        if (strSecret.length == 0 || forceNewKey) {
+            val keyGenerator = KeyGenerator.getInstance(totp.getAlgorithm());
+            keyGenerator.init(Constants.OTP_GENERATED_KEY_LENGTH_BITS);
+            val generatedKey = keyGenerator.generateKey();
+            keyBytes = generatedKey.encoded
+            sp.putString(R.string.key_smscommunicator_otp_secret, Base64.encodeToString(keyBytes, Base64.NO_WRAP + Base64.NO_PADDING))
+        } else {
+            keyBytes = Base64.decode(strSecret, Base64.DEFAULT);
+        }
+        key = SecretKeySpec(keyBytes, 0, keyBytes.size, "SHA1")
+    }
+
+    private fun configure() {
+        ensureKey()
+        pin = sp.getString(R.string.key_smscommunicator_otp_pin, "").trim()
+    }
+
+    private fun generateOneTimePassword(counter: Long): String {
+        if (key != null) {
+            return String.format("%06d", totp.generateOneTimePassword(key, counter))
+        } else {
+            return ""
+        }
+    }
+
+    /**
+     * Check if given OTP+PIN is valid
+     */
+    fun checkOTP(otp: String): OneTimePasswordValidationResult {
+        configure()
+        val normalisedOtp = otp.replace(" ", "").replace("-", "").trim()
+
+        if (pin.length < 3) {
+            return OneTimePasswordValidationResult.ERROR_WRONG_PIN
+        }
+
+        if (normalisedOtp.length != (6 + pin.length)) {
+            return OneTimePasswordValidationResult.ERROR_WRONG_LENGTH
+        }
+
+        if (!normalisedOtp.substring(6).equals(pin)) {
+            return OneTimePasswordValidationResult.ERROR_WRONG_PIN
+        }
+
+        val milis: Long = DateTimeUtils.currentTimeMillis()
+        val counter: Long = (milis / 30000L)
+
+        var acceptableTokens: MutableList<String> = mutableListOf(generateOneTimePassword(counter))
+        for (i in 0 until Constants.OTP_ACCEPT_OLD_TOKENS_COUNT) {
+            acceptableTokens.add(generateOneTimePassword(counter - i - 1))
+        }
+        val candidateOtp = normalisedOtp.substring(0, 6)
+
+        if (acceptableTokens.any { candidate -> candidateOtp.equals(candidate) }) {
+            return OneTimePasswordValidationResult.OK
+        }
+
+        return OneTimePasswordValidationResult.ERROR_WRONG_OTP
+    }
+
+    /**
+     * Return URI used to provision Authenticator apps
+     */
+    fun provisioningURI(): String? {
+        val keyImm = key
+        if (keyImm != null) {
+            return "otpauth://totp/AndroidAPS:" + URLEncoder.encode(name(), "utf-8") + "?secret=" + BaseEncoding.base32().encode(keyImm.encoded).replace("=", "") + "&issuer=AndroidAPS"
+        } else {
+            return null
+        }
+    }
+
+}
--- a/app/src/main/java/info/nightscout/androidaps/utils/textValidator/DefaultEditTextValidator.kt
+++ b/app/src/main/java/info/nightscout/androidaps/utils/textValidator/DefaultEditTextValidator.kt
@ -117,6 +117,7 @@ class DefaultEditTextValidator : EditTextValidator {
            EditTextValidator.TEST_EMAIL               -> toAdd = EmailValidator(if (TextUtils.isEmpty(testErrorString)) context.getString(R.string.error_email_address_not_valid) else testErrorString)
            EditTextValidator.TEST_PHONE               -> toAdd = PhoneValidator(if (TextUtils.isEmpty(testErrorString)) context.getString(R.string.error_phone_not_valid) else testErrorString)
            EditTextValidator.TEST_MULTI_PHONE         -> toAdd = MultiPhoneValidator(if (TextUtils.isEmpty(testErrorString)) context.getString(R.string.error_phone_not_valid) else testErrorString)
+            EditTextValidator.TEST_PIN_STRENGTH        -> toAdd = PinStrengthValidator(if (TextUtils.isEmpty(testErrorString)) context.getString(R.string.error_pin_not_valid) else testErrorString)
            EditTextValidator.TEST_DOMAINNAME          -> toAdd = DomainValidator(if (TextUtils.isEmpty(testErrorString)) context.getString(R.string.error_domain_not_valid) else testErrorString)
            EditTextValidator.TEST_IPADDRESS           -> toAdd = IpAddressValidator(if (TextUtils.isEmpty(testErrorString)) context.getString(R.string.error_ip_not_valid) else testErrorString)
            EditTextValidator.TEST_WEBURL              -> toAdd = WebUrlValidator(if (TextUtils.isEmpty(testErrorString)) context.getString(R.string.error_url_not_valid) else testErrorString)
--- a/app/src/main/java/info/nightscout/androidaps/utils/textValidator/EditTextValidator.java
+++ b/app/src/main/java/info/nightscout/androidaps/utils/textValidator/EditTextValidator.java
@ -93,4 +93,6 @@ public interface EditTextValidator {

    int TEST_MULTI_PHONE = 19;

+    int TEST_PIN_STRENGTH = 20;
+
 }
--- a/app/src/main/java/info/nightscout/androidaps/utils/textValidator/validators/PinStrengthValidator.kt
+++ b/app/src/main/java/info/nightscout/androidaps/utils/textValidator/validators/PinStrengthValidator.kt
@ -0,0 +1,41 @@
+package info.nightscout.androidaps.utils.textValidator.validators
+
+import android.widget.EditText
+
+class PinStrengthValidator(val _customErrorMessage: String?) : Validator(_customErrorMessage) {
+
+    val regex = "[0-9]{3,6}".toRegex()
+
+    override fun isValid(editText: EditText): Boolean {
+        return try {
+            val value = editText.text.toString()
+            if (!regex.matches(value))
+                return false
+
+            var last = ' '
+            var rising = true
+            var falling = true
+            var same = true
+            value.forEachIndexed { i, c ->
+                if (i > 0) {
+                    if (last != c) {
+                        same = false
+                    }
+
+                    if (last.toInt() + 1 != c.toInt()) {
+                        falling = false
+                    }
+
+                    if (last.toInt() != c.toInt() + 1) {
+                        rising = false
+                    }
+                }
+                last = c
+            }
+
+            !rising && !falling && !same
+        } catch (e: NumberFormatException) {
+            false
+        }
+    }
+}
--- a/app/src/main/res/layout/smscommunicator_fragment.xml
+++ b/app/src/main/res/layout/smscommunicator_fragment.xml
@ -4,15 +4,48 @@
    android:layout_height="match_parent"
    tools:context=".plugins.general.smsCommunicator.SmsCommunicatorFragment">

-    <ScrollView
-        android:layout_width="fill_parent"
-        android:layout_height="fill_parent">
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:orientation="vertical">

-        <TextView
-            android:id="@+id/smscommunicator_log"
-            android:layout_width="fill_parent"
-            android:layout_height="fill_parent"
-            android:text=""/>
-    </ScrollView>
+        <com.google.android.flexbox.FlexboxLayout xmlns:app="http://schemas.android.com/apk/res-auto"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:background="@color/defaultbackground"
+            app:alignContent="stretch"
+            app:alignItems="stretch"
+            app:flexDirection="row"
+            app:flexWrap="wrap"
+            app:justifyContent="center">
+
+            <TextView
+                android:id="@+id/smscomunicator_tab_log"
+                android:layout_width="wrap_content"
+                android:layout_height="30dp"
+                android:layout_weight="1"
+                android:gravity="center_vertical|center_horizontal"
+                android:paddingLeft="5dp"
+                android:paddingRight="5dp"
+                android:text="@string/smscomunicator_tab_log_label" />
+
+            <TextView
+                android:id="@+id/smscomunicator_tab_otp"
+                android:layout_width="wrap_content"
+                android:layout_height="30dp"
+                android:layout_weight="1"
+                android:gravity="center_vertical|center_horizontal"
+                android:paddingLeft="5dp"
+                android:paddingRight="5dp"
+                android:text="@string/smscomunicator_tab_otp_label" />
+
+        </com.google.android.flexbox.FlexboxLayout>
+
+        <FrameLayout
+            android:id="@+id/smscomunicator_fragment_container"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content" />
+
+    </LinearLayout>

 </FrameLayout>
--- a/app/src/main/res/layout/smscommunicator_fragment_log.xml
+++ b/app/src/main/res/layout/smscommunicator_fragment_log.xml
@ -0,0 +1,19 @@
+<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".plugins.general.smsCommunicator.fragments.SmsCommunicatorLogFragment">
+
+    <ScrollView
+        android:layout_width="fill_parent"
+        android:layout_height="fill_parent">
+
+        <TextView
+            android:id="@+id/smscommunicator_log"
+            android:layout_width="fill_parent"
+            android:layout_height="fill_parent"
+            android:text="" />
+
+    </ScrollView>
+
+</FrameLayout>
--- a/app/src/main/res/layout/smscommunicator_fragment_otp.xml
+++ b/app/src/main/res/layout/smscommunicator_fragment_otp.xml
@ -0,0 +1,104 @@
+<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".plugins.general.smsCommunicator.fragments.SmsCommunicatorOtpFragment">
+
+    <ScrollView
+        android:layout_width="fill_parent"
+        android:layout_height="fill_parent">
+
+        <LinearLayout
+            android:id="@+id/smscommunicator_otp_layout"
+            android:layout_width="fill_parent"
+            android:layout_height="wrap_content"
+            android:orientation="vertical">
+
+            <TextView
+                style="@style/section_header_label"
+                android:text="@string/smscommunicator_otp_step1_install_header" />
+
+            <TextView
+                android:layout_width="fill_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="5sp"
+                android:layout_marginBottom="5sp"
+                android:paddingStart="15sp"
+                android:paddingEnd="15sp"
+                android:text="@string/smscommunicator_otp_install_info" />
+
+            <TextView
+                style="@style/section_header_label"
+                android:text="@string/smscommunicator_otp_step2_provisioning_header" />
+
+            <ImageView
+                android:id="@+id/smscommunicator_otp_provisioning"
+                android:layout_width="fill_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="10dp"
+                android:scaleType="center" />
+
+            <TextView
+                style="@style/warning_label"
+                android:text="" />
+
+            <TextView
+                style="@style/section_header_label"
+                android:text="@string/smscommunicator_otp_step3_test_header" />
+
+            <LinearLayout
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:orientation="horizontal">
+
+                <TextView
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:paddingStart="15dp"
+                    android:paddingEnd="5dp"
+                    android:text="@string/smscommunicator_otp_verify_label" />
+
+                <EditText
+                    android:id="@+id/smscommunicator_otp_verify_edit"
+                    android:layout_width="140sp"
+                    android:layout_height="wrap_content"
+                    android:hint="000 000 000"
+                    android:inputType="number"
+                    android:maxLength="12"
+                    android:textAlignment="center"
+                    android:textSize="19sp"
+                    tools:ignore="HardcodedText" />
+
+                <TextView
+                    android:id="@+id/smscommunicator_otp_verify_label"
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:paddingStart="15dp"
+                    android:paddingEnd="5dp" />
+
+            </LinearLayout>
+
+            <TextView
+                style="@style/section_header_label"
+                android:text="@string/smscommunicator_otp_reset_header" />
+
+            <TextView
+                style="@style/warning_label"
+                android:text="@string/smscommunicator_otp_reset_warning" />
+
+            <info.nightscout.androidaps.utils.SingleClickButton
+                android:id="@+id/actions_smscommunicator_otp_reset"
+                style="?android:attr/buttonStyle"
+                android:layout_width="fill_parent"
+                android:layout_height="match_parent"
+                android:layout_marginLeft="10dp"
+                android:layout_marginTop="3dp"
+                android:layout_marginRight="10dp"
+                android:layout_marginBottom="3dp"
+                android:text="@string/smscommunicator_otp_reset_btn"
+                android:textColor="@color/colorTreatmentButton" />
+
+        </LinearLayout>
+    </ScrollView>
+
+</FrameLayout>
--- a/app/src/main/res/values/fet_attrs.xml
+++ b/app/src/main/res/values/fet_attrs.xml
@ -23,6 +23,7 @@
            <enum name="httpsUrl" value="17" />
            <enum name="minLength" value="18" />
            <enum name="multiPhone" value="19" />
+            <enum name="pinStrength" value="20" />
        </attr>
        <attr name="testErrorString" format="string" />
        <attr name="emptyErrorString" format="string" />
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@ -1702,4 +1702,38 @@
    <string name="loop_tbrrequest_time_label">Temp basal request time</string>
    <string name="loop_tbrexecution_time_label">Temp basal execution time</string>

+    <!-- SMS Communicator & OTP Authenticator -->
+
+    <string name="key_smscommunicator_otp_enabled" translatable="false">smscommunicator_otp_enabled</string>
+    <string name="key_smscommunicator_otp_name" translatable="false">smscommunicator_otp_name</string>
+    <string name="key_smscommunicator_otp_pin" translatable="false">smscommunicator_otp_pin</string>
+    <string name="key_smscommunicator_otp_secret" translatable="false">smscommunicator_otp_secret</string>
+
+    <string name="smscommunicator_default_user_display_name" comment="This is default user display name, shown by Authenticators">User</string>
+    <string name="smscommunicator_code_from_authenticator_for" comment="This is continuation of sentence: To [ACTION] reply with code">from Authenticator app for: %1$s</string>
+
+    <string name="smscommunicator_otp_enabled">Enable Authenticator</string>
+    <string name="smscommunicator_otp_enabled_summary">Authenticate commands using One Time Passwords generated by Google Authenticator or similar 2FA apps.</string>
+    <string name="smscommunicator_otp_pin">Additional PIN at token end</string>
+    <string name="smscommunicator_otp_pin_summary">Additional digits that should be memorised and glued at end of each generated One Time Password</string>
+    <string name="smscommunicator_otp_name">User name for Authenticator</string>
+    <string name="smscommunicator_otp_name_summary">User name displayed along with generated OTP on Authenticator App</string>
+
+    <string name="smscomunicator_tab_log_label">Operations Log</string>
+    <string name="smscomunicator_tab_otp_label">Authenticator</string>
+
+    <string name="smscommunicator_otp_verify_label">OTP to check:</string>
+    <string name="smscommunicator_otp_reset_btn">Reset Authenticators</string>
+    <string name="smscommunicator_otp_reset_title">Reset Authenticator Key</string>
+    <string name="smscommunicator_otp_reset_prompt">Are you sure to reset Authenticator key? It will render all currently configured Authenticators invalid, and you will need to set them up again.</string>
+    <string name="smscommunicator_otp_reset_successful">New Authenticator Key was generated! Please use updated QRCode to provision authenticators.</string>
+
+    <string name="smscommunicator_otp_step1_install_header">1. Install Authenticator</string>
+    <string name="smscommunicator_otp_step2_provisioning_header">2. Scan code to setup AndroidAPS OTP codes</string>
+    <string name="smscommunicator_otp_step3_test_header">3. Test One-Time-Password</string>
+    <string name="smscommunicator_otp_reset_header">Reset Authenticators</string>
+
+    <string name="smscommunicator_otp_install_info">On each follower phone install Authenticator app that support RFC 6238 TOTP tokens. Popular free apps are:\n • Google Authenticator\n • LastPass Authenticator\n • FreeOTP Authenticator</string>
+    <string name="smscommunicator_otp_provisioning_warning">DO NOT SHARE this code online!\nUse it only to setup Authenticator App on follower phones.</string>
+    <string name="smscommunicator_otp_reset_warning">By reseting authenticator you make all already provisioned authenticators invalid. You will need to set up them again!</string>
 </resources>
--- a/app/src/main/res/values/styles.xml
+++ b/app/src/main/res/values/styles.xml
@ -49,4 +49,24 @@

    <style name="AppTheme.AppBarOverlay" parent="ThemeOverlay.AppCompat.Dark.ActionBar" />

+    <style name="section_header_label">
+        <item name="android:layout_width">match_parent</item>
+        <item name="android:layout_height">wrap_content</item>
+        <item name="android:layout_marginTop">15dp</item>
+        <item name="android:paddingStart">15dp</item>
+        <item name="android:paddingEnd">15dp</item>
+        <item name="android:textColor">@color/colorAccent</item>
+    </style>
+
+    <style name="warning_label">
+        <item name="android:layout_width">match_parent</item>
+        <item name="android:layout_height">wrap_content</item>
+        <item name="android:layout_marginTop">5dp</item>
+        <item name="android:layout_marginBottom">5dp</item>
+        <item name="android:paddingStart">15dp</item>
+        <item name="android:paddingEnd">15dp</item>
+        <item name="android:textAlignment">center</item>
+        <item name="android:textColor">#ff0000</item>
+    </style>
+
 </resources>
--- a/app/src/main/res/values/validator.xml
+++ b/app/src/main/res/values/validator.xml
@ -17,6 +17,7 @@
    <string name="error_mustbe4digitnumber">Must be 4 digit number</string>
    <string name="error_mustbe6digitnumber">Must be 6 digit number</string>
    <string name="error_not_a_minimum_length">Not a minimum length</string>
+    <string name="error_pin_not_valid">Pin should be 3 to 6 digits, not same or in series</string>

    <string name="fourdigitnumber" translatable="false">^\\d{4}</string>

--- a/app/src/main/res/xml/pref_smscommunicator.xml
+++ b/app/src/main/res/xml/pref_smscommunicator.xml
@ -27,6 +27,25 @@
            validate:minNumber="3"
            validate:testType="numericRange" />

+        <SwitchPreference
+            android:defaultValue="false"
+            android:key="@string/key_smscommunicator_otp_enabled"
+            android:title="@string/smscommunicator_otp_enabled"
+            android:summary="@string/smscommunicator_otp_enabled_summary"/>
+
+        <info.nightscout.androidaps.utils.textValidator.ValidatingEditTextPreference
+            android:key="@string/key_smscommunicator_otp_pin"
+            android:summary="@string/smscommunicator_otp_pin_summary"
+            android:title="@string/smscommunicator_otp_pin"
+            validate:testType="pinStrength" />
+
+        <info.nightscout.androidaps.utils.textValidator.ValidatingEditTextPreference
+            android:key="@string/key_smscommunicator_otp_name"
+            android:summary="@string/smscommunicator_otp_name_summary"
+            android:title="@string/smscommunicator_otp_name"
+            validate:testType="personName" />
+
+
    </PreferenceCategory>

 </androidx.preference.PreferenceScreen>
--- a/app/src/test/java/info/AAPSMocker.java
+++ b/app/src/test/java/info/AAPSMocker.java
@ -9,6 +9,7 @@ import org.json.JSONObject;
 import org.junit.Assert;
 import org.powermock.api.mockito.PowerMockito;

+import java.util.Base64;
 import java.util.Locale;

 import info.nightscout.androidaps.Constants;
@ -27,6 +28,7 @@ import info.nightscout.androidaps.plugins.iob.iobCobCalculator.IobCobCalculatorP
 import info.nightscout.androidaps.plugins.treatments.TreatmentService;
 import info.nightscout.androidaps.plugins.treatments.TreatmentsPlugin;
 import info.nightscout.androidaps.queue.CommandQueue;
+import info.nightscout.androidaps.utils.OneTimePassword;
 import info.nightscout.androidaps.utils.SP;

 import static org.mockito.ArgumentMatchers.any;
@ -294,4 +296,7 @@ public class AAPSMocker {
        return iobCobCalculatorPlugin;
    }

+    public static void mockOTP() {
+        PowerMockito.when(OneTimePassword.getInstance().isEnabled()).thenReturn(false);
+    }
 }
--- a/app/src/test/java/info/nightscout/androidaps/plugins/general/smsCommunicator/SmsCommunicatorPluginTest.java
+++ b/app/src/test/java/info/nightscout/androidaps/plugins/general/smsCommunicator/SmsCommunicatorPluginTest.java
@ -2,6 +2,8 @@ package info.nightscout.androidaps.plugins.general.smsCommunicator;

 import android.telephony.SmsManager;

+import com.google.firebase.auth.OAuthCredential;
+
 import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
@ -41,6 +43,7 @@ import info.nightscout.androidaps.plugins.treatments.TreatmentsPlugin;
 import info.nightscout.androidaps.queue.Callback;
 import info.nightscout.androidaps.queue.CommandQueue;
 import info.nightscout.androidaps.utils.DateUtil;
+import info.nightscout.androidaps.utils.OneTimePassword;
 import info.nightscout.androidaps.utils.SP;
 import info.nightscout.androidaps.utils.T;
 import info.nightscout.androidaps.utils.XdripCalibrations;
@ -68,6 +71,7 @@ import static org.powermock.api.mockito.PowerMockito.when;
 public class SmsCommunicatorPluginTest {

    private SmsCommunicatorPlugin smsCommunicatorPlugin;
+    private OneTimePassword otp;
    private LoopPlugin loopPlugin;

    private boolean hasBeenRun = false;
@ -87,7 +91,7 @@ public class SmsCommunicatorPluginTest {
        Assert.assertTrue(smsCommunicatorPlugin.isCommand("BOLUS", ""));
        smsCommunicatorPlugin.setMessageToConfirm(null);
        Assert.assertFalse(smsCommunicatorPlugin.isCommand("BLB", ""));
-        smsCommunicatorPlugin.setMessageToConfirm(new AuthRequest(smsCommunicatorPlugin, new Sms("1234", "ddd"), "RequestText", "ccode", new SmsAction() {
+        smsCommunicatorPlugin.setMessageToConfirm(new AuthRequest(smsCommunicatorPlugin, new Sms("1234", "ddd"), otp, "RequestText", "ccode", new SmsAction() {
            @Override
            public void run() {
            }
@ -892,6 +896,7 @@ public class SmsCommunicatorPluginTest {
        AAPSMocker.mockConfigBuilder();
        AAPSMocker.mockCommandQueue();
        AAPSMocker.mockNSUpload();
+        AAPSMocker.mockOTP();
        ConstraintChecker constraintChecker = AAPSMocker.mockConstraintsChecker();

        BgReading reading = new BgReading();