feat(dashpay): add timeskew support to CoinJoinService and warning di…

…alogs (#1252)

* feat: add handling for timeskew

wallet/res/values/strings-extra.xml

@@ -697,4 +697,6 @@
     <string name="masternode_key_not_used">Not used</string>
     <string name="masternode_key_revoked">Revoked</string>
     <string name="masternode_key_private_public_base64">Private / Public Keys (base64)</string>
+    <string name="timeskew_ahead">ahead</string>
+    <string name="timeskew_behind">behind</string>
 </resources>

wallet/res/values/strings.xml

@@ -43,6 +43,8 @@
     <string name="wallet_low_storage_dialog_button_apps">Manage apps</string>
     <string name="wallet_timeskew_dialog_title">Check date &amp; time settings</string>
     <string name="wallet_timeskew_dialog_msg">Your device time is off by %d minutes. You probably cannot send or receive Dash due to this problem.\n\nYou should check and if necessary correct your date, time and timezone settings.</string>
+    <string name="wallet_coinjoin_timeskew_dialog_msg">Your device time is %s by %d seconds. You cannot use CoinJoin due to this difference.\n\nThe time settings on your device needs to be changed to “Set time automatically” to use CoinJoin.</string>
+    <string name="settings_coinjoin_timeskew_dialog_msg">Your device time is off by more than 5 seconds. You cannot use CoinJoin due to this difference.\n\nThe time settings on your device needs to be changed to “Set time automatically” before using CoinJoin.</string>
     <string name="send_coins_activity_title">Send Dash</string>
     <string name="send_coins_fragment_request_payment_request_progress">Fetching signature from %s…</string>
     <string name="send_coins_fragment_request_payment_request_failed_title">Fetching signature failed</string>

wallet/src/de/schildbach/wallet/service/CoinJoinService.kt

@@ -17,9 +17,15 @@
 
 package de.schildbach.wallet.service
 
+import android.content.BroadcastReceiver
+import android.content.Context
+import android.content.Intent
+import android.content.IntentFilter
 import com.google.common.base.Stopwatch
+import dagger.hilt.android.qualifiers.ApplicationContext
 import de.schildbach.wallet.data.CoinJoinConfig
 import de.schildbach.wallet.ui.dashpay.PlatformRepo
+import de.schildbach.wallet.util.getTimeSkew
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.asCoroutineDispatcher
@@ -50,7 +56,6 @@ import org.bitcoinj.coinjoin.utils.CoinJoinManager
 import org.bitcoinj.coinjoin.utils.CoinJoinTransactionType
 import org.bitcoinj.core.AbstractBlockChain
 import org.bitcoinj.core.Coin
-import org.bitcoinj.core.Context
 import org.bitcoinj.core.ECKey
 import org.bitcoinj.core.MasternodeAddress
 import org.bitcoinj.core.Transaction
@@ -84,6 +89,7 @@ interface CoinJoinService {
     suspend fun getMixingState(): MixingStatus
     fun observeMixingState(): Flow<MixingStatus>
     fun observeMixingProgress(): Flow<Double>
+    fun updateTimeSkew(timeSkew: Long)
 }
 
 enum class MixingStatus {
@@ -94,8 +100,12 @@ enum class MixingStatus {
     ERROR // An error stopped the mixing process
 }
 
+const val MAX_ALLOWED_AHEAD_TIMESKEW = 5000L // 5 seconds
+const val MAX_ALLOWED_BEHIND_TIMESKEW = 20000L // 20 seconds
+
 @Singleton
 class CoinJoinMixingService @Inject constructor(
+    @ApplicationContext private val context: Context,
     val walletDataProvider: WalletDataProvider,
     private val blockchainStateProvider: BlockchainStateProvider,
     private val config: CoinJoinConfig,
@@ -111,7 +121,15 @@ class CoinJoinMixingService @Inject constructor(
         const val DEFAULT_DENOMINATIONS_HARDCAP = 300
 
         // these are not for production
-        val FAST_MIXING_DENOMINATIONS_REMOVE = listOf<Denomination>() // Denomination.THOUSANDTH)
+        val FAST_MIXING_DENOMINATIONS_REMOVE = listOf<Denomination>() // Denomination.THOUSANDTH
+
+        fun isInsideTimeSkewBounds(timeSkew: Long): Boolean {
+            return if (timeSkew > 0) {
+                timeSkew < MAX_ALLOWED_AHEAD_TIMESKEW
+            } else {
+                (-timeSkew) < MAX_ALLOWED_BEHIND_TIMESKEW
+            }
+        }
     }
 
     private val coinJoinManager: CoinJoinManager?
@@ -140,12 +158,25 @@ class CoinJoinMixingService @Inject constructor(
     private var networkStatus: NetworkStatus = NetworkStatus.UNKNOWN
     private var isSynced = false
     private var hasAnonymizableBalance: Boolean = false
+    private var timeSkew: Long = 0L
 
     // https://stackoverflow.com/questions/55421710/how-to-suspend-kotlin-coroutine-until-notified
     private val updateMutex = Mutex(locked = false)
     private val updateMixingStateMutex = Mutex(locked = false)
     private var exception: Throwable? = null
 
+    private val timeChangeReceiver = object: BroadcastReceiver() {
+        override fun onReceive(context: Context?, intent: Intent?) {
+            if (intent?.action == Intent.ACTION_TIME_CHANGED) {
+                // Time has changed, handle the change here
+                log.info("Time or Time Zone changed")
+                coroutineScope.launch {
+                    updateTimeSkewInternal(getTimeSkew())
+                }
+            }
+        }
+    }
+
     override fun observeMixingProgress(): Flow<Double> = _progressFlow
 
     init {
@@ -168,7 +199,7 @@ class CoinJoinMixingService @Inject constructor(
             .onEach { blockChainState ->
                 val isSynced = blockChainState.isSynced()
                 if (isSynced != this.isSynced) {
-                    updateState(config.getMode(), hasAnonymizableBalance, networkStatus, isSynced, blockChain)
+                    updateState(config.getMode(), timeSkew, hasAnonymizableBalance, networkStatus, isSynced, blockChain)
                 }
                 // this will trigger mixing as new blocks are mined and received tx's are confirmed
                 if (isSynced) {
@@ -196,9 +227,18 @@ class CoinJoinMixingService @Inject constructor(
             .launchIn(coroutineScope)
     }
 
+    /** updates timeSkew in #[coroutineScope] */
+    override fun updateTimeSkew(timeSkew: Long) {
+        coroutineScope.launch {
+            updateTimeSkewInternal(timeSkew)
+        }
+    }
+
+    suspend fun updateTimeSkewInternal(timeSkew: Long) {
+        updateState(config.getMode(), timeSkew, hasAnonymizableBalance, networkStatus, isSynced, blockChain)
+    }
+
     private suspend fun updateBalance(balance: Coin) {
-        // leave this ui scope
-        Context.propagate(walletDataProvider.wallet!!.context)
         CoinJoinClientOptions.setAmount(balance)
         log.info("coinjoin: total balance: ${balance.toFriendlyString()}")
         val walletEx = walletDataProvider.wallet as WalletEx
@@ -223,9 +263,14 @@ class CoinJoinMixingService @Inject constructor(
             else -> false
         }
 
-        log.info("coinjoin: mixing can occur: $hasBalanceLeftToMix = balance: (${anonBalance.isGreaterThan(CoinJoin.getSmallestDenomination())} && canDenominate: $canDenominate) || partially-mixed: $hasPartiallyMixedCoins")
+        log.info(
+            "coinjoin: mixing can occur: $hasBalanceLeftToMix = balance: (${anonBalance.isGreaterThan(
+                CoinJoin.getSmallestDenomination()
+            )} && canDenominate: $canDenominate) || partially-mixed: $hasPartiallyMixedCoins"
+        )
         updateState(
             config.getMode(),
+            getTimeSkew(),
             hasBalanceLeftToMix,
             networkStatus,
             isSynced,
@@ -235,26 +280,29 @@ class CoinJoinMixingService @Inject constructor(
 
     private suspend fun updateState(
         mode: CoinJoinMode,
+        timeSkew: Long,
         hasAnonymizableBalance: Boolean,
         networkStatus: NetworkStatus,
         isSynced: Boolean,
         blockChain: AbstractBlockChain?
     ) {
         updateMutex.lock()
         log.info(
-            "coinjoin-old-state: ${this.mode}, ${this.hasAnonymizableBalance}, ${this.networkStatus}, synced: ${this.isSynced} ${blockChain != null}"
+            "coinjoin-old-state: ${this.mode}, ${this.timeSkew}ms, ${this.hasAnonymizableBalance}, ${this.networkStatus}, synced: ${this.isSynced} ${blockChain != null}"
         )
         try {
             setBlockchain(blockChain)
             log.info(
-                "coinjoin-new-state: $mode, $hasAnonymizableBalance, $networkStatus, synced: $isSynced, ${blockChain != null}"
+                "coinjoin-new-state: $mode, $timeSkew ms, $hasAnonymizableBalance, $networkStatus, synced: $isSynced, ${blockChain != null}"
             )
+            log.info("coinjoin-Current timeskew: ${getTimeSkew()}")
             this.networkStatus = networkStatus
             this.hasAnonymizableBalance = hasAnonymizableBalance
             this.isSynced = isSynced
             this.mode = mode
+            this.timeSkew = timeSkew
 
-            if (mode == CoinJoinMode.NONE) {
+            if (mode == CoinJoinMode.NONE || !isInsideTimeSkewBounds(timeSkew)) {
                 updateMixingState(MixingStatus.NOT_STARTED)
             } else {
                 configureMixing()
@@ -302,11 +350,11 @@ class CoinJoinMixingService @Inject constructor(
     }
 
     private suspend fun updateBlockChain(blockChain: AbstractBlockChain?) {
-        updateState(mode, hasAnonymizableBalance, networkStatus, isSynced, blockChain)
+        updateState(mode, timeSkew, hasAnonymizableBalance, networkStatus, isSynced, blockChain)
     }
 
     private suspend fun updateNetworkStatus(networkStatus: NetworkStatus) {
-        updateState(mode, hasAnonymizableBalance, networkStatus, isSynced, blockChain)
+        updateState(mode, timeSkew, hasAnonymizableBalance, networkStatus, isSynced, blockChain)
     }
 
     private suspend fun updateMode(mode: CoinJoinMode) {
@@ -315,7 +363,8 @@ class CoinJoinMixingService @Inject constructor(
             configureMixing()
             updateBalance(walletDataProvider.wallet!!.getBalance(Wallet.BalanceType.AVAILABLE))
         }
-        updateState(mode, hasAnonymizableBalance, networkStatus, isSynced, blockChain)
+        val currentTimeSkew = getTimeSkew()
+        updateState(mode, currentTimeSkew, hasAnonymizableBalance, networkStatus, isSynced, blockChain)
     }
 
     private var mixingProgressTracker: MixingProgressTracker = object : MixingProgressTracker() {
@@ -475,15 +524,19 @@ class CoinJoinMixingService @Inject constructor(
     }
 
     private suspend fun startMixing(): Boolean {
-        Context.propagate(walletDataProvider.wallet!!.context)
+        val filter = IntentFilter().apply {
+            addAction(Intent.ACTION_TIME_CHANGED)
+        }
+        context.registerReceiver(timeChangeReceiver, filter)
         clientManager.setBlockChain(blockChain)
         return if (!clientManager.startMixing()) {
             log.info("Mixing has been started already.")
             false
         } else {
             // run this on a different thread?
             val asyncStart = coroutineScope.async(Dispatchers.IO) {
-                Context.propagate(walletDataProvider.wallet!!.context)
+                // though coroutineScope is on a Context propogated thread, we still need this
+                org.bitcoinj.core.Context.propagate(walletDataProvider.wallet!!.context)
                 coinJoinManager?.initMasternodeGroup(blockChain)
                 clientManager.doAutomaticDenominating()
             }
@@ -511,6 +564,7 @@ class CoinJoinMixingService @Inject constructor(
         sessionCompleteListeners.forEach { coinJoinManager?.removeSessionCompleteListener(it) }
         clientManager.stopMixing()
         coinJoinManager?.stop()
+        context.unregisterReceiver(timeChangeReceiver)
     }
 
     private fun setBlockchain(blockChain: AbstractBlockChain?) {

wallet/src/de/schildbach/wallet/ui/coinjoin/CoinJoinLevelFragment.kt

@@ -17,7 +17,9 @@
 
 package de.schildbach.wallet.ui.coinjoin
 
+import android.content.Intent
 import android.os.Bundle
+import android.provider.Settings
 import android.view.View
 import androidx.fragment.app.Fragment
 import androidx.fragment.app.viewModels
@@ -81,7 +83,7 @@ class CoinJoinLevelFragment : Fragment(R.layout.fragment_coinjoin_level) {
         }
     }
 
-    private fun showConnectionWaringDialog(mode: CoinJoinMode) {
+    private fun showConnectionWarningDialog(mode: CoinJoinMode) {
         AdaptiveDialog.create(
             R.drawable.ic_warning,
             getString(
@@ -123,9 +125,27 @@ class CoinJoinLevelFragment : Fragment(R.layout.fragment_coinjoin_level) {
                 }
             }
         } else if (viewModel.isWifiConnected()) {
-            setMode(mode)
+            val settingsIntent = Intent(Settings.ACTION_DATE_SETTINGS)
+            val hasSettings = requireActivity().packageManager.resolveActivity(settingsIntent, 0) != null
+            lifecycleScope.launch {
+                if (viewModel.isTimeSkewedForCoinJoin()) {
+                    AdaptiveDialog.create(
+                        R.drawable.ic_coinjoin,
+                        getString(R.string.coinjoin),
+                        getString(R.string.settings_coinjoin_timeskew_dialog_msg),
+                        getString(R.string.cancel),
+                        if (hasSettings) getString(R.string.button_settings) else null
+                    ).show(requireActivity()) { openSettings ->
+                        if (openSettings == true && hasSettings) {
+                            startActivity(settingsIntent)
+                        }
+                    }
+                } else {
+                    setMode(mode)
+                }
+            }
         } else {
-            showConnectionWaringDialog(mode)
+            showConnectionWarningDialog(mode)
         }
     }
 

wallet/src/de/schildbach/wallet/ui/coinjoin/CoinJoinLevelViewModel.kt

@@ -22,6 +22,10 @@ import androidx.lifecycle.viewModelScope
 import dagger.hilt.android.lifecycle.HiltViewModel
 import de.schildbach.wallet.data.CoinJoinConfig
 import de.schildbach.wallet.service.CoinJoinMode
+import de.schildbach.wallet.service.CoinJoinService
+import de.schildbach.wallet.service.MAX_ALLOWED_AHEAD_TIMESKEW
+import de.schildbach.wallet.service.MAX_ALLOWED_BEHIND_TIMESKEW
+import de.schildbach.wallet.util.getTimeSkew
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.filterNotNull
@@ -35,6 +39,7 @@ import javax.inject.Inject
 open class CoinJoinLevelViewModel @Inject constructor(
     private val analytics: AnalyticsService,
     private val coinJoinConfig: CoinJoinConfig,
+    private val coinJoinService: CoinJoinService,
     private var networkState: NetworkStateInt
 ) : ViewModel() {
 
@@ -64,4 +69,18 @@ open class CoinJoinLevelViewModel @Inject constructor(
     fun logEvent(event: String) {
         analytics.logEvent(event, mapOf())
     }
+
+    suspend fun isTimeSkewedForCoinJoin(): Boolean {
+        return try {
+            val timeSkew = getTimeSkew()
+            coinJoinService.updateTimeSkew(timeSkew)
+            if (timeSkew > 0) {
+                timeSkew > MAX_ALLOWED_AHEAD_TIMESKEW
+            } else {
+                -timeSkew > MAX_ALLOWED_BEHIND_TIMESKEW
+            }
+        } catch (e: Exception) {
+            false
+        }
+    }
 }

wallet/src/de/schildbach/wallet/ui/dashpay/CreateIdentityService.kt

@@ -130,7 +130,7 @@ class CreateIdentityService : LifecycleService() {
     }
 
     private val walletApplication by lazy { application as WalletApplication }
-    @Inject lateinit var platformRepo: PlatformRepo// by lazy { PlatformRepo.getInstance() }
+    @Inject lateinit var platformRepo: PlatformRepo
     @Inject lateinit var platformSyncService: PlatformSyncService
     @Inject lateinit var userAlertDao: UserAlertDao
     @Inject lateinit var blockchainIdentityDataDao: BlockchainIdentityConfig

wallet/src/de/schildbach/wallet/ui/main/MainActivity.kt

@@ -18,6 +18,7 @@
 package de.schildbach.wallet.ui.main
 
 import android.Manifest
+import android.content.BroadcastReceiver
 import android.content.Context
 import android.content.Intent
 import android.content.IntentFilter
@@ -50,6 +51,7 @@ import de.schildbach.wallet.ui.dashpay.*
 import de.schildbach.wallet.ui.invite.AcceptInviteActivity
 import de.schildbach.wallet.ui.invite.InviteHandler
 import de.schildbach.wallet.ui.invite.InviteSendContactRequestDialog
+import de.schildbach.wallet.ui.main.WalletActivityExt.checkLowStorageAlert
 import de.schildbach.wallet.ui.main.WalletActivityExt.checkTimeSkew
 import de.schildbach.wallet.ui.main.WalletActivityExt.handleFirebaseAction
 import de.schildbach.wallet.ui.main.WalletActivityExt.requestDisableBatteryOptimisation
@@ -109,7 +111,7 @@ class MainActivity : AbstractBindServiceActivity(), ActivityCompat.OnRequestPerm
 
     val requestPermissionLauncher = registerForActivityResult(ActivityResultContracts.RequestPermission()) { _ ->
         requestDisableBatteryOptimisation()
-    };
+    }
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
@@ -129,9 +131,9 @@ class MainActivity : AbstractBindServiceActivity(), ActivityCompat.OnRequestPerm
 
         handleIntent(intent)
 
-        //Prevent showing dialog twice or more when activity is recreated (e.g: rotating device, etc)
+        // Prevent showing dialog twice or more when activity is recreated (e.g: rotating device, etc)
         if (savedInstanceState == null) {
-            //Add BIP44 support and PIN if missing
+            // Add BIP44 support and PIN if missing
             upgradeWalletKeyChains(Constants.BIP44_PATH, false)
         }
 
@@ -143,6 +145,9 @@ class MainActivity : AbstractBindServiceActivity(), ActivityCompat.OnRequestPerm
                 currencies.component1()!!, currencies.component2()!!
             )
         }
+        val timeChangedFilter = IntentFilter().apply {
+            addAction(Intent.ACTION_TIME_CHANGED)
+        }
     }
 
     override fun onStart() {
@@ -532,13 +537,6 @@ class MainActivity : AbstractBindServiceActivity(), ActivityCompat.OnRequestPerm
         }
     }
 
-    private fun checkLowStorageAlert() {
-        val stickyIntent = registerReceiver(null, IntentFilter(Intent.ACTION_DEVICE_STORAGE_LOW))
-        if (stickyIntent != null) {
-            showLowStorageAlertDialog()
-        }
-    }
-
     override fun onOptionsItemSelected(item: MenuItem): Boolean {
         when (item.itemId) {
             android.R.id.home -> {