epic18: Manage VPN services for Tor or Tracker control

4 files changed, 340 insertions, 0 deletions

diff --git a/trackersserviceeos/src/main/java/foundation/e/advancedprivacy/trackers/service/DNSBlocker.kt b/trackersserviceeos/src/main/java/foundation/e/advancedprivacy/trackers/service/DNSBlocker.kt
new file mode 100644
index 0000000..6a2b218
--- /dev/null
+++ b/trackersserviceeos/src/main/java/foundation/e/advancedprivacy/trackers/service/DNSBlocker.kt
@@ -0,0 +1,104 @@
+/*
+ * Copyright (C) 2023 MURENA SAS
+ * Copyright (C) 2022 E FOUNDATION
+ *
+ * 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
+
+import android.net.LocalServerSocket
+import android.system.ErrnoException
+import android.system.Os
+import android.system.OsConstants
+import foundation.e.advancedprivacy.core.utils.runSuspendCatching
+import foundation.e.advancedprivacy.trackers.domain.usecases.FilterHostnameUseCase
+import kotlinx.coroutines.CancellationException
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.isActive
+import kotlinx.coroutines.launch
+import timber.log.Timber
+import java.io.BufferedReader
+import java.io.InputStreamReader
+import java.io.PrintWriter
+
+class DNSBlocker(
+    val filterHostnameUseCase: FilterHostnameUseCase
+) {
+    private var resolverReceiver: LocalServerSocket? = null
+
+    companion object {
+        private const val SOCKET_NAME = "foundation.e.advancedprivacy"
+    }
+
+    private fun closeSocket() {
+        // Known bug and workaround that LocalServerSocket::close is not working well
+        // https://issuetracker.google.com/issues/36945762
+        if (resolverReceiver != null) {
+            try {
+                Os.shutdown(resolverReceiver!!.fileDescriptor, OsConstants.SHUT_RDWR)
+                resolverReceiver!!.close()
+                resolverReceiver = null
+            } catch (e: ErrnoException) {
+                if (e.errno != OsConstants.EBADF) {
+                    Timber.w("Socket already closed")
+                } else {
+                    Timber.e(e, "Exception: cannot close DNS port on stop $SOCKET_NAME !")
+                }
+            } catch (e: Exception) {
+                Timber.e(e, "Exception: cannot close DNS port on stop $SOCKET_NAME !")
+            }
+        }
+    }
+
+    fun listenJob(scope: CoroutineScope): Job = scope.launch(Dispatchers.IO) {
+        val resolverReceiver = runSuspendCatching {
+            LocalServerSocket(SOCKET_NAME)
+        }.getOrElse {
+            Timber.e(it, "Exception: cannot open DNS port on $SOCKET_NAME")
+            return@launch
+        }
+
+        this@DNSBlocker.resolverReceiver = resolverReceiver
+        Timber.d("DNSFilterProxy running on port $SOCKET_NAME")
+
+        while (isActive) {
+            runSuspendCatching {
+                val socket = resolverReceiver.accept()
+                val reader = BufferedReader(InputStreamReader(socket.inputStream))
+                val line = reader.readLine()
+                val params = line.split(",").toTypedArray()
+                val output = socket.outputStream
+                val writer = PrintWriter(output, true)
+                val domainName = params[0]
+                val appUid = params[1].toInt()
+                if (filterHostnameUseCase.shouldBlock(domainName, appUid)) {
+                    writer.println("block")
+                } else {
+                    writer.println("pass")
+                }
+                socket.close()
+            }.onFailure {
+                if (it is CancellationException) {
+                    closeSocket()
+                    throw it
+                } else {
+                    Timber.w(it, "Exception while listening DNS resolver")
+                }
+            }
+        }
+    }
+}
diff --git a/trackersserviceeos/src/main/java/foundation/e/advancedprivacy/trackers/service/TrackersService.kt b/trackersserviceeos/src/main/java/foundation/e/advancedprivacy/trackers/service/TrackersService.kt
new file mode 100644
index 0000000..5f573b0
--- /dev/null
+++ b/trackersserviceeos/src/main/java/foundation/e/advancedprivacy/trackers/service/TrackersService.kt
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2023 MURENA SAS
+ * Copyright (C) 2021 E FOUNDATION
+ *
+ * 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
+
+import android.app.Service
+import android.content.Intent
+import android.os.IBinder
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.cancel
+import org.koin.java.KoinJavaComponent.get
+
+class TrackersService : Service() {
+    companion object {
+        const val ACTION_START = "foundation.e.privacymodules.trackers.intent.action.START"
+
+        var coroutineScope = CoroutineScope(Dispatchers.IO)
+    }
+
+    override fun onBind(intent: Intent): IBinder? {
+        throw UnsupportedOperationException("Not yet implemented")
+    }
+
+    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
+        if (ACTION_START == intent?.action) {
+            stop()
+            start()
+        }
+        return START_REDELIVER_INTENT
+    }
+
+    private fun start() {
+        coroutineScope = CoroutineScope(Dispatchers.IO)
+        get<DNSBlocker>(DNSBlocker::class.java).apply {
+            filterHostnameUseCase.writeLogJob(coroutineScope)
+            listenJob(coroutineScope)
+        }
+    }
+
+    private fun stop() {
+        kotlin.runCatching { coroutineScope.cancel() }
+    }
+}
diff --git a/trackersserviceeos/src/main/java/foundation/e/advancedprivacy/trackers/service/TrackersSupervisorEos.kt b/trackersserviceeos/src/main/java/foundation/e/advancedprivacy/trackers/service/TrackersSupervisorEos.kt
new file mode 100644
index 0000000..71a4fc4
--- /dev/null
+++ b/trackersserviceeos/src/main/java/foundation/e/advancedprivacy/trackers/service/TrackersSupervisorEos.kt
@@ -0,0 +1,70 @@
+/*
+ * 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
+
+import android.content.Context
+import android.content.Intent
+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.TrackersService.Companion.ACTION_START
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.isActive
+import org.koin.core.module.dsl.bind
+import org.koin.core.module.dsl.factoryOf
+import org.koin.core.module.dsl.singleOf
+import org.koin.core.qualifier.named
+import org.koin.dsl.module
+
+class TrackersSupervisorEos(private val context: Context) : TrackersSupervisor {
+
+    override val state: StateFlow<FeatureState> = MutableStateFlow(FeatureState.ON)
+
+    override fun start(): Boolean {
+        val intent = Intent(context, TrackersService::class.java)
+        intent.action = ACTION_START
+        return context.startService(intent) != null
+    }
+
+    override fun stop(): Boolean {
+        return context.stopService(Intent(context, TrackersService::class.java))
+    }
+
+    override fun isRunning(): Boolean {
+        return TrackersService.coroutineScope.isActive
+    }
+
+    override val dnsFilterForIpScrambling = null
+}
+
+val trackerServiceModule = module {
+    factoryOf(::DNSBlocker)
+    singleOf(::TrackersSupervisorEos) {
+        bind<TrackersSupervisor>()
+    }
+    single<VpnSupervisorUseCase> {
+        VpnSupervisorUseCaseEos(
+            localStateRepository = get(),
+            orbotSupervisor = get(),
+            trackersSupervisor = get(),
+            appDesc = get(named("AdvancedPrivacy")),
+            permissionsPrivacyModule = get(),
+            scope = get(),
+        )
+    }
+}
diff --git a/trackersserviceeos/src/main/java/foundation/e/advancedprivacy/trackers/service/VpnSupervisorUseCaseEos.kt b/trackersserviceeos/src/main/java/foundation/e/advancedprivacy/trackers/service/VpnSupervisorUseCaseEos.kt
new file mode 100644
index 0000000..976a2b7
--- /dev/null
+++ b/trackersserviceeos/src/main/java/foundation/e/advancedprivacy/trackers/service/VpnSupervisorUseCaseEos.kt
@@ -0,0 +1,108 @@
+/*
+ * 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
+
+import foundation.e.advancedprivacy.domain.entities.ApplicationDescription
+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.permissions.IPermissionsPrivacyModule
+import foundation.e.advancedprivacy.ipscrambler.OrbotSupervisor
+import foundation.e.advancedprivacy.trackers.domain.externalinterfaces.TrackersSupervisor
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.flow.drop
+import kotlinx.coroutines.flow.dropWhile
+import kotlinx.coroutines.launch
+
+class VpnSupervisorUseCaseEos(
+    private val localStateRepository: LocalStateRepository,
+    private val orbotSupervisor: OrbotSupervisor,
+    private val trackersSupervisor: TrackersSupervisor,
+    private val appDesc: ApplicationDescription,
+    private val permissionsPrivacyModule: IPermissionsPrivacyModule,
+    private val scope: CoroutineScope,
+) : VpnSupervisorUseCase {
+
+    override fun listenSettings() {
+        trackersSupervisor.start()
+
+        scope.launch(Dispatchers.IO) {
+            localStateRepository.ipScramblingSetting.collect {
+                applySettings(it)
+            }
+        }
+
+        scope.launch(Dispatchers.IO) {
+            localStateRepository.blockTrackers.drop(1).dropWhile { !it }.collect {
+                localStateRepository.emitStartVpnDisclaimer(TrackersControl())
+            }
+        }
+    }
+
+    private suspend fun applySettings(isIpScramblingEnabled: Boolean) {
+        val currentMode = localStateRepository.internetPrivacyMode.value
+        when {
+            (
+                isIpScramblingEnabled &&
+                    currentMode in setOf(FeatureState.OFF, FeatureState.STOPPING)
+                ) -> {
+                applyStartIpScrambling()
+            }
+            (
+                !isIpScramblingEnabled &&
+                    currentMode in setOf(FeatureState.ON, FeatureState.STARTING)
+                ) -> {
+                orbotSupervisor.stop()
+            }
+            else -> {}
+        }
+    }
+
+    private suspend fun applyStartIpScrambling() {
+        if (orbotSupervisor.prepareAndroidVpn() != null) {
+            permissionsPrivacyModule.setVpnPackageAuthorization(appDesc.packageName)
+            val alwaysOnVpnPackage = permissionsPrivacyModule.getAlwaysOnVpnPackage()
+            if (alwaysOnVpnPackage != null) {
+                localStateRepository.emitOtherVpnRunning(
+                    permissionsPrivacyModule.getApplicationDescription(
+                        packageName = alwaysOnVpnPackage,
+                        withIcon = false
+                    )
+                )
+                localStateRepository.setIpScramblingSetting(enabled = false)
+                return
+            }
+        }
+
+        localStateRepository.emitStartVpnDisclaimer(IpScrambling())
+        startVpnService(IpScrambling())
+    }
+
+    override fun startVpnService(feature: MainFeatures) {
+        localStateRepository.internetPrivacyMode.value = FeatureState.STARTING
+        orbotSupervisor.setDNSFilter(null)
+        orbotSupervisor.start()
+    }
+
+    override fun cancelStartVpnService(feature: MainFeatures) {
+        localStateRepository.setIpScramblingSetting(enabled = false)
+    }
+}