epic18: Manage VPN services for Tor or Tracker control

5 files changed, 181 insertions, 26 deletions

diff --git a/trackersservicestandalone/build.gradle b/trackersservicestandalone/build.gradle
index ead9dbd..5b574cd 100644
--- a/trackersservicestandalone/build.gradle
+++ b/trackersservicestandalone/build.gradle
@@ -29,6 +29,7 @@ android {
 dependencies {
     implementation project(":core")
     implementation project(":trackers")
+    implementation project(":ipscrambling")
 
     implementation(
         libs.androidx.core.ktx,
diff --git a/trackersservicestandalone/src/main/java/foundation/e/advancedprivacy/trackers/service/TrackersService.kt b/trackersservicestandalone/src/main/java/foundation/e/advancedprivacy/trackers/service/TrackersService.kt
index 918977f..152a3e9 100644
--- a/trackersservicestandalone/src/main/java/foundation/e/advancedprivacy/trackers/service/TrackersService.kt
+++ b/trackersservicestandalone/src/main/java/foundation/e/advancedprivacy/trackers/service/TrackersService.kt
@@ -16,16 +16,15 @@
  */
 package foundation.e.advancedprivacy.trackers.service
 
-import android.content.Context
 import android.content.Intent
 import android.net.VpnService
 import android.os.Build
 import android.os.ParcelFileDescriptor
 import foundation.e.advancedprivacy.core.utils.notificationBuilder
-import foundation.e.advancedprivacy.domain.entities.FeatureServiceState
+import foundation.e.advancedprivacy.domain.entities.FeatureState
 import foundation.e.advancedprivacy.domain.entities.NOTIFICATION_TRACKER_FLAG
 import foundation.e.advancedprivacy.domain.entities.NotificationContent
-import foundation.e.advancedprivacy.trackers.domain.externalinterfaces.TrackersServiceSupervisor
+import foundation.e.advancedprivacy.trackers.domain.externalinterfaces.TrackersSupervisor
 import foundation.e.advancedprivacy.trackers.service.Config.DNS_SERVER_TO_CATCH_IPV4
 import foundation.e.advancedprivacy.trackers.service.Config.DNS_SERVER_TO_CATCH_IPV6
 import foundation.e.advancedprivacy.trackers.service.Config.SESSION_NAME
@@ -39,18 +38,12 @@ import timber.log.Timber
 class TrackersService : VpnService() {
     companion object {
         var coroutineScope = CoroutineScope(Dispatchers.IO)
-
-        fun start(context: Context) {
-            prepare(context)
-            val intent = Intent(context, TrackersService::class.java)
-            context.startService(intent)
-        }
     }
 
     private val networkDNSAddressRepository: NetworkDNSAddressRepository = get(NetworkDNSAddressRepository::class.java)
-    private val trackersServiceSupervisor: TrackersServiceSupervisorImpl = get(
-        TrackersServiceSupervisor::class.java
-    ) as TrackersServiceSupervisorImpl
+    private val trackersSupervisor: TrackersSupervisorStandalone = get(
+        TrackersSupervisor::class.java
+    ) as TrackersSupervisorStandalone
 
     private val notificationTrackerFlag: NotificationContent = get(NotificationContent::class.java, named("notificationTrackerFlag"))
 
@@ -64,14 +57,14 @@ class TrackersService : VpnService() {
                 content = notificationTrackerFlag
             ).build()
         )
-        trackersServiceSupervisor.state.value = FeatureServiceState.ON
+        trackersSupervisor.mutableState.value = FeatureState.ON
 
         return START_STICKY
     }
 
     override fun onDestroy() {
         networkDNSAddressRepository.stop()
-        trackersServiceSupervisor.state.value = FeatureServiceState.OFF
+        trackersSupervisor.mutableState.value = FeatureState.OFF
         super.onDestroy()
     }
 
diff --git a/trackersservicestandalone/src/main/java/foundation/e/advancedprivacy/trackers/service/TrackersServiceSupervisorImpl.kt b/trackersservicestandalone/src/main/java/foundation/e/advancedprivacy/trackers/service/TrackersSupervisorStandalone.kt
index e2a6692..ac06ced 100644
--- a/trackersservicestandalone/src/main/java/foundation/e/advancedprivacy/trackers/service/TrackersServiceSupervisorImpl.kt
+++ b/trackersservicestandalone/src/main/java/foundation/e/advancedprivacy/trackers/service/TrackersSupervisorStandalone.kt
@@ -18,37 +18,42 @@ package foundation.e.advancedprivacy.trackers.service
 
 import android.content.Context
 import android.content.Intent
-import foundation.e.advancedprivacy.domain.entities.FeatureServiceState
-import foundation.e.advancedprivacy.trackers.domain.externalinterfaces.TrackersServiceSupervisor
+import foundation.e.advancedprivacy.domain.entities.FeatureState
+import foundation.e.advancedprivacy.domain.usecases.VpnSupervisorUseCase
+import foundation.e.advancedprivacy.trackers.domain.externalinterfaces.TrackersSupervisor
 import foundation.e.advancedprivacy.trackers.service.data.NetworkDNSAddressRepository
 import foundation.e.advancedprivacy.trackers.service.data.RequestDNSRepository
 import foundation.e.advancedprivacy.trackers.service.usecases.ResolveDNSUseCase
+import foundation.e.advancedprivacy.trackers.service.usecases.VpnSupervisorUseCaseStandalone
 import kotlinx.coroutines.cancel
 import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
 import org.koin.core.module.dsl.bind
 import org.koin.core.module.dsl.singleOf
 import org.koin.dsl.module
 import org.pcap4j.packet.DnsPacket
 import java.util.function.Function
 
-class TrackersServiceSupervisorImpl(
+class TrackersSupervisorStandalone(
     private val context: Context,
     private val resolveDNSUseCase: ResolveDNSUseCase
-) : TrackersServiceSupervisor {
-    internal val state: MutableStateFlow<FeatureServiceState> = MutableStateFlow(FeatureServiceState.OFF)
+) : TrackersSupervisor {
+    internal val mutableState: MutableStateFlow<FeatureState> = MutableStateFlow(FeatureState.OFF)
+    override val state: StateFlow<FeatureState> = mutableState
 
     override fun start(): Boolean {
         return if (!isRunning()) {
-            state.value = FeatureServiceState.STARTING
-            TrackersService.start(context)
+            mutableState.value = FeatureState.STARTING
+            val intent = Intent(context, TrackersService::class.java)
+            context.startService(intent)
             true
         } else false
     }
 
     override fun stop(): Boolean {
-        return when (state.value) {
-            FeatureServiceState.ON -> {
-                state.value = FeatureServiceState.STOPPING
+        return when (mutableState.value) {
+            FeatureState.ON -> {
+                mutableState.value = FeatureState.STOPPING
                 kotlin.runCatching { TrackersService.coroutineScope.cancel() }
                 context.stopService(Intent(context, TrackersService::class.java))
                 true
@@ -58,7 +63,7 @@ class TrackersServiceSupervisorImpl(
     }
 
     override fun isRunning(): Boolean {
-        return state.value != FeatureServiceState.OFF
+        return state.value != FeatureState.OFF
     }
 
     override val dnsFilterForIpScrambling = Function<DnsPacket?, DnsPacket?> { dnsRequest -> resolveDNSUseCase.shouldBlock(dnsRequest) }
@@ -69,5 +74,6 @@ val trackerServiceModule = module {
     singleOf(::RequestDNSRepository)
     singleOf(::ResolveDNSUseCase)
     singleOf(::TunLooper)
-    singleOf(::TrackersServiceSupervisorImpl) { bind<TrackersServiceSupervisor>() }
+    singleOf(::TrackersSupervisorStandalone) { bind<TrackersSupervisor>() }
+    singleOf(::VpnSupervisorUseCaseStandalone) { bind<VpnSupervisorUseCase>() }
 }
diff --git a/trackersservicestandalone/src/main/java/foundation/e/advancedprivacy/trackers/service/TunLooper.kt b/trackersservicestandalone/src/main/java/foundation/e/advancedprivacy/trackers/service/TunLooper.kt
index 7813c67..bb349eb 100644
--- a/trackersservicestandalone/src/main/java/foundation/e/advancedprivacy/trackers/service/TunLooper.kt
+++ b/trackersservicestandalone/src/main/java/foundation/e/advancedprivacy/trackers/service/TunLooper.kt
@@ -84,6 +84,7 @@ class TunLooper(
                 }
             }
         }
+        closeStreams()
     }
 
     private suspend fun handleIpPacket(buffer: ByteArray, pLen: Int) {
diff --git a/trackersservicestandalone/src/main/java/foundation/e/advancedprivacy/trackers/service/usecases/VpnSupervisorUseCaseStandalone.kt b/trackersservicestandalone/src/main/java/foundation/e/advancedprivacy/trackers/service/usecases/VpnSupervisorUseCaseStandalone.kt
new file mode 100644
index 0000000..683f886
--- /dev/null
+++ b/trackersservicestandalone/src/main/java/foundation/e/advancedprivacy/trackers/service/usecases/VpnSupervisorUseCaseStandalone.kt
@@ -0,0 +1,154 @@
+/*
+ * Copyright (C) 2023 MURENA SAS
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package foundation.e.advancedprivacy.trackers.service.usecases
+
+import foundation.e.advancedprivacy.domain.entities.FeatureState
+import foundation.e.advancedprivacy.domain.entities.MainFeatures
+import foundation.e.advancedprivacy.domain.entities.MainFeatures.IpScrambling
+import foundation.e.advancedprivacy.domain.entities.MainFeatures.TrackersControl
+import foundation.e.advancedprivacy.domain.repositories.LocalStateRepository
+import foundation.e.advancedprivacy.domain.usecases.VpnSupervisorUseCase
+import foundation.e.advancedprivacy.externalinterfaces.servicesupervisors.FeatureSupervisor
+import foundation.e.advancedprivacy.ipscrambler.OrbotSupervisor
+import foundation.e.advancedprivacy.trackers.domain.externalinterfaces.TrackersSupervisor
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.flow.combine
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.flow.launchIn
+import kotlinx.coroutines.launch
+
+class VpnSupervisorUseCaseStandalone(
+    private val localStateRepository: LocalStateRepository,
+    private val trackersSupervisor: TrackersSupervisor,
+    private val orbotSupervisor: OrbotSupervisor,
+    private val scope: CoroutineScope,
+) : VpnSupervisorUseCase {
+    private var applySettingJob: Job? = null
+
+    init {
+        listenSettings()
+    }
+
+    override fun listenSettings() {
+        var previousBlockTrackers: Boolean? = null
+
+        localStateRepository.blockTrackers.combine(
+            localStateRepository.ipScramblingSetting
+        ) { blockTrackers, hideIp ->
+            applySettingJob?.cancel()
+            applySettingJob = scope.launch {
+                when {
+                    blockTrackers && !hideIp ->
+                        launchVpnService(trackersSupervisor)
+
+                    !blockTrackers && !hideIp ->
+                        stopAllServices()
+
+                    else -> {
+                        if (blockTrackers && previousBlockTrackers != true) {
+                            localStateRepository.emitStartVpnDisclaimer(IpScrambling())
+                        }
+
+                        launchVpnService(orbotSupervisor)
+                    }
+                }
+
+                previousBlockTrackers = blockTrackers
+            }
+        }.launchIn(scope)
+    }
+
+    private fun stopAllServices() {
+        listOf(orbotSupervisor, trackersSupervisor).map { stopVpnService(it) }
+    }
+
+    private fun stopVpnService(supervisor: FeatureSupervisor): FeatureSupervisor {
+        when (supervisor.state.value) {
+            FeatureState.ON,
+            FeatureState.STARTING ->
+                supervisor.stop()
+
+            else -> {}
+        }
+        return supervisor
+    }
+
+    private suspend fun launchVpnService(supervisor: FeatureSupervisor) {
+        stopVpnService(otherSupervisor(supervisor)).let { otherSupervisor ->
+            otherSupervisor.state.first { it == FeatureState.OFF }
+        }
+
+        when (supervisor.state.value) {
+            FeatureState.STOPPING -> {
+                supervisor.state.first { it == FeatureState.OFF }
+                initiateStartVpnService(supervisor)
+            }
+
+            FeatureState.OFF -> initiateStartVpnService(supervisor)
+            else -> {}
+        }
+    }
+
+    private fun otherSupervisor(supervisor: FeatureSupervisor): FeatureSupervisor {
+        return when (supervisor) {
+            trackersSupervisor -> orbotSupervisor
+            else -> trackersSupervisor
+        }
+    }
+
+    private fun getSupervisor(feature: MainFeatures): FeatureSupervisor {
+        return when (feature) {
+            is TrackersControl -> trackersSupervisor
+            else -> orbotSupervisor
+        }
+    }
+
+    private suspend fun initiateStartVpnService(supervisor: FeatureSupervisor) {
+        val authorizeVpnIntent = orbotSupervisor.prepareAndroidVpn()
+        val feature = when (supervisor) {
+            trackersSupervisor -> TrackersControl(authorizeVpnIntent)
+            else -> IpScrambling(authorizeVpnIntent)
+        }
+
+        if (authorizeVpnIntent == null) {
+            localStateRepository.emitStartVpnDisclaimer(feature)
+            startVpnService(feature)
+        } else {
+            localStateRepository.emitStartVpnDisclaimer(feature)
+        }
+    }
+
+    override fun startVpnService(feature: MainFeatures) {
+        if (feature is IpScrambling) {
+            localStateRepository.internetPrivacyMode.value = FeatureState.STARTING
+            orbotSupervisor.setDNSFilter(trackersSupervisor.dnsFilterForIpScrambling)
+        }
+
+        getSupervisor(feature).start()
+    }
+
+    override fun cancelStartVpnService(feature: MainFeatures) {
+        when (feature) {
+            is IpScrambling ->
+                localStateRepository.setIpScramblingSetting(enabled = false)
+            is TrackersControl ->
+                trackersSupervisor.stop()
+            else -> {}
+        }
+    }
+}