Permission compatibility layer for new subsystem

Bug: 252884423
Test: presubmit
Change-Id: I9718cf13bec4fb4e5d3b39bddafe69e89310e2e1

4 files changed, 389 insertions, 18 deletions

diff --git a/services/permission/java/com/android/server/permission/access/collection/IndexedMap.kt b/services/permission/java/com/android/server/permission/access/collection/IndexedMap.kt
index 43f18e27f7aa..1e73be7923ae 100644
--- a/services/permission/java/com/android/server/permission/access/collection/IndexedMap.kt
+++ b/services/permission/java/com/android/server/permission/access/collection/IndexedMap.kt
@@ -148,6 +148,13 @@ inline fun <K, V> IndexedMap<K, V>.retainAllIndexed(predicate: (Int, K, V) -> Bo
     return isChanged
 }
 
+inline fun <K, V, R> IndexedMap<K, V>.mapNotNullIndexed(transform: (K, V) -> R?): IndexedList<R> =
+    IndexedList<R>().also { destination ->
+        forEachIndexed { _, key, value ->
+            transform(key, value)?.let { destination += it }
+        }
+    }
+
 @Suppress("NOTHING_TO_INLINE")
 inline operator fun <K, V> IndexedMap<K, V>.set(key: K, value: V) {
     put(key, value)
diff --git a/services/permission/java/com/android/server/permission/access/permission/Permission.kt b/services/permission/java/com/android/server/permission/access/permission/Permission.kt
index efa5bf3118d6..cbf94f565e63 100644
--- a/services/permission/java/com/android/server/permission/access/permission/Permission.kt
+++ b/services/permission/java/com/android/server/permission/access/permission/Permission.kt
@@ -31,6 +31,9 @@ data class Permission(
     inline val packageName: String
         get() = permissionInfo.packageName
 
+    inline val groupName: String?
+        get() = permissionInfo.group
+
     inline val isDynamic: Boolean
         get() = type == TYPE_DYNAMIC
 
@@ -40,6 +43,9 @@ data class Permission(
     inline val isRuntime: Boolean
         get() = permissionInfo.protection == PermissionInfo.PROTECTION_DANGEROUS
 
+    inline val isAppOp: Boolean
+        get() = permissionInfo.protection == PermissionInfo.PROTECTION_FLAG_APPOP
+
     inline val isSoftRestricted: Boolean
         get() = permissionInfo.protectionFlags.hasBits(PermissionInfo.FLAG_SOFT_RESTRICTED)
 
@@ -109,6 +115,9 @@ data class Permission(
     inline val isKnownSigner: Boolean
         get() = permissionInfo.protectionFlags.hasBits(PermissionInfo.PROTECTION_FLAG_KNOWN_SIGNER)
 
+    inline val hasGids: Boolean
+        get() = throw NotImplementedError()
+
     inline val protectionLevel: Int
         @Suppress("DEPRECATION")
         get() = permissionInfo.protectionLevel
diff --git a/services/permission/java/com/android/server/permission/access/permission/PermissionService.kt b/services/permission/java/com/android/server/permission/access/permission/PermissionService.kt
index 82017362da29..a70468e2400d 100644
--- a/services/permission/java/com/android/server/permission/access/permission/PermissionService.kt
+++ b/services/permission/java/com/android/server/permission/access/permission/PermissionService.kt
@@ -16,6 +16,11 @@
 
 package com.android.server.permission.access.permission
 
+import android.Manifest
+import android.app.ActivityManager
+import android.compat.annotation.ChangeId
+import android.compat.annotation.EnabledAfter
+import android.content.Context
 import android.content.pm.PackageManager
 import android.content.pm.PackageManagerInternal
 import android.content.pm.PermissionGroupInfo
@@ -23,17 +28,32 @@ import android.content.pm.PermissionInfo
 import android.content.pm.permission.SplitPermissionInfoParcelable
 import android.os.Binder
 import android.os.Build
+import android.os.Handler
+import android.os.HandlerThread
+import android.os.Looper
+import android.os.Message
 import android.os.Process
+import android.os.RemoteCallbackList
+import android.os.RemoteException
+import android.os.ServiceManager
 import android.os.UserHandle
 import android.permission.IOnPermissionsChangeListener
+import android.permission.PermissionManager
+import android.provider.Settings
+import android.util.Log
+import com.android.internal.compat.IPlatformCompat
+import com.android.server.FgThread
 import com.android.server.LocalManagerRegistry
 import com.android.server.LocalServices
+import com.android.server.ServiceThread
+import com.android.server.SystemConfig
 import com.android.server.pm.PackageManagerLocal
 import com.android.server.pm.permission.PermissionManagerServiceInterface
 import com.android.server.permission.access.AccessCheckingService
 import com.android.server.permission.access.PermissionUri
 import com.android.server.permission.access.UidUri
 import com.android.server.permission.access.collection.* // ktlint-disable no-wildcard-imports
+import com.android.server.permission.access.util.hasAnyBit
 import com.android.server.permission.access.util.hasBits
 import com.android.server.pm.UserManagerService
 import com.android.server.pm.permission.LegacyPermission
@@ -53,21 +73,56 @@ class PermissionService(
     private val policy =
         service.getSchemePolicy(UidUri.SCHEME, PermissionUri.SCHEME) as UidPermissionPolicy
 
+    private val context = service.context
     private lateinit var packageManagerInternal: PackageManagerInternal
     private lateinit var packageManagerLocal: PackageManagerLocal
+    private lateinit var platformCompat: IPlatformCompat
     private lateinit var userManagerService: UserManagerService
 
     private val mountedStorageVolumes = IndexedSet<String?>()
 
+    private lateinit var handlerThread: HandlerThread
+    private lateinit var handler: Handler
+
+    private lateinit var onPermissionsChangeListeners: OnPermissionsChangeListeners
+    private lateinit var permissionFlagsListener: OnPermissionFlagsChangedListener
+
     fun initialize() {
         packageManagerInternal = LocalServices.getService(PackageManagerInternal::class.java)
         packageManagerLocal =
             LocalManagerRegistry.getManagerOrThrow(PackageManagerLocal::class.java)
+        platformCompat = IPlatformCompat.Stub.asInterface(
+            ServiceManager.getService(Context.PLATFORM_COMPAT_SERVICE)
+        )
         userManagerService = UserManagerService.getInstance()
+
+        handlerThread = ServiceThread(LOG_TAG, Process.THREAD_PRIORITY_BACKGROUND, true)
+        handler = Handler(handlerThread.looper)
+
+        onPermissionsChangeListeners = OnPermissionsChangeListeners(FgThread.get().looper)
+        permissionFlagsListener = OnPermissionFlagsChangedListener()
+        policy.addOnPermissionFlagsChangedListener(permissionFlagsListener)
     }
 
     override fun getAllPermissionGroups(flags: Int): List<PermissionGroupInfo> {
-        TODO("Not yet implemented")
+        val callingUid = Binder.getCallingUid()
+        packageManagerLocal.withUnfilteredSnapshot().use { snapshot ->
+            if (snapshot.isUidInstantApp(callingUid)) {
+                return emptyList()
+            }
+
+            val permissionGroups = service.getState {
+                with(policy) { getPermissionGroups() }
+            }
+
+            return permissionGroups.mapNotNullIndexed { _, permissionGroup ->
+                if (snapshot.isPackageVisibleToUid(permissionGroup.packageName, callingUid)) {
+                    permissionGroup.generatePermissionGroupInfo(flags)
+                } else {
+                    null
+                }
+            }
+        }
     }
 
     override fun getPermissionGroupInfo(
@@ -82,7 +137,7 @@ class PermissionService(
             }
 
             permissionGroup = service.getState {
-                with(policy) { getPermissionGroup(permissionGroupName) }
+                with(policy) { getPermissionGroups()[permissionGroupName] }
             } ?: return null
 
             val isPermissionGroupVisible =
@@ -120,7 +175,7 @@ class PermissionService(
             }
 
             permission = service.getState {
-                with(policy) { getPermission(permissionName) }
+                with(policy) { getPermissions()[permissionName] }
             } ?: return null
 
             val isPermissionVisible =
@@ -148,7 +203,7 @@ class PermissionService(
      */
     private fun Permission.generatePermissionInfo(
         flags: Int,
-        targetSdkVersion: Int
+        targetSdkVersion: Int = Build.VERSION_CODES.CUR_DEVELOPMENT
     ): PermissionInfo =
         @Suppress("DEPRECATION")
         PermissionInfo(permissionInfo).apply {
@@ -165,10 +220,40 @@ class PermissionService(
         }
 
     override fun queryPermissionsByGroup(
-        permissionGroupName: String,
+        permissionGroupName: String?,
         flags: Int
-    ): List<PermissionInfo> {
-        TODO("Not yet implemented")
+    ): List<PermissionInfo>? {
+        val callingUid = Binder.getCallingUid()
+        packageManagerLocal.withUnfilteredSnapshot().use { snapshot ->
+            if (snapshot.isUidInstantApp(callingUid)) {
+                return null
+            }
+
+            if (permissionGroupName != null) {
+                val permissionGroup = service.getState {
+                    with(policy) { getPermissionGroups()[permissionGroupName] }
+                } ?: return null
+
+                if (!snapshot.isPackageVisibleToUid(
+                        permissionGroup.packageName, callingUid
+                    )) {
+                    return null
+                }
+            }
+
+            val permissions = service.getState {
+                with(policy) { getPermissions() }
+            }
+
+            return permissions.mapNotNullIndexed { _, permission ->
+                if (permission.groupName == permissionGroupName &&
+                    snapshot.isPackageVisibleToUid(permission.packageName, callingUid)) {
+                    permission.generatePermissionInfo(flags)
+                } else {
+                    null
+                }
+            }
+        }
     }
 
     override fun getAllPermissionsWithProtection(protection: Int): List<PermissionInfo> {
@@ -224,11 +309,11 @@ class PermissionService(
     }
 
     override fun addOnPermissionsChangeListener(listener: IOnPermissionsChangeListener) {
-        TODO("Not yet implemented")
+        onPermissionsChangeListeners.addListener(listener)
     }
 
     override fun removeOnPermissionsChangeListener(listener: IOnPermissionsChangeListener) {
-        TODO("Not yet implemented")
+        onPermissionsChangeListeners.removeListener(listener)
     }
 
     override fun getPermissionFlags(packageName: String, permissionName: String, userId: Int): Int {
@@ -245,16 +330,49 @@ class PermissionService(
         permissionName: String,
         userId: Int
     ): Boolean {
-        TODO("Not yet implemented")
+        if (UserHandle.getCallingUserId() != userId) {
+            context.enforceCallingPermission(
+                Manifest.permission.INTERACT_ACROSS_USERS_FULL,
+                "isPermissionRevokedByPolicy for user $userId"
+            )
+        }
+
+        if (checkPermission(packageName, permissionName, userId) ==
+            PackageManager.PERMISSION_GRANTED) {
+            return false
+        }
+
+        val callingUid = Binder.getCallingUid()
+        if (packageManagerLocal.withUnfilteredSnapshot()
+            .use { !it.isPackageVisibleToUid(packageName, userId, callingUid) }) {
+            return false
+        }
+
+        val permissionFlags = getPermissionFlagsUnchecked(packageName,
+            permissionName, callingUid, userId)
+        return permissionFlags.hasBits(PackageManager.FLAG_PERMISSION_POLICY_FIXED)
+    }
+
+    private fun getPermissionFlagsUnchecked(
+        packageName: String,
+        permName: String,
+        callingUid: Int,
+        userId: Int
+    ): Int {
+        throw NotImplementedError()
     }
 
     override fun isPermissionsReviewRequired(packageName: String, userId: Int): Boolean {
+        requireNotNull(packageName) { "packageName" }
+        // TODO(b/173235285): Some caller may pass USER_ALL as userId.
+        // Preconditions.checkArgumentNonnegative(userId, "userId");
         val packageState = packageManagerLocal.withUnfilteredSnapshot()
             .use { it.packageStates[packageName] } ?: return false
         val permissionFlags = service.getState {
             with(policy) { getUidPermissionFlags(packageState.appId, userId) }
         } ?: return false
-        return permissionFlags.anyIndexed { _, _, flags -> PermissionFlags.isReviewRequired(flags) }
+        return permissionFlags.anyIndexed { _, _, flags -> PermissionFlags.isReviewRequired(flags)
+        }
     }
 
     override fun shouldShowRequestPermissionRationale(
@@ -262,7 +380,70 @@ class PermissionService(
         permissionName: String,
         userId: Int
     ): Boolean {
-        TODO("Not yet implemented")
+        val callingUid = Binder.getCallingUid()
+        if (UserHandle.getCallingUserId() != userId) {
+            context.enforceCallingPermission(
+                Manifest.permission.INTERACT_ACROSS_USERS_FULL,
+                "canShowRequestPermissionRationale for user $userId"
+            )
+        }
+
+        val appId = packageManagerLocal.withUnfilteredSnapshot().use { snapshot ->
+            snapshot.packageStates[packageName]?.appId ?: return false
+        }
+        if (UserHandle.getAppId(callingUid) != appId) {
+            return false
+        }
+
+        if (checkPermission(packageName, permissionName, userId) ==
+            PackageManager.PERMISSION_GRANTED) {
+            return false
+        }
+
+        val identity = Binder.clearCallingIdentity()
+        val permissionFlags = try {
+            getPermissionFlagsInternal(packageName, permissionName, callingUid, userId)
+        } finally {
+            Binder.restoreCallingIdentity(identity)
+        }
+
+        val fixedFlags = (PermissionFlags.SYSTEM_FIXED or PermissionFlags.POLICY_FIXED
+            or PermissionFlags.USER_FIXED)
+
+        if (permissionFlags.hasAnyBit(fixedFlags) ||
+            permissionFlags.hasBits(PermissionFlags.RESTRICTION_REVOKED)) {
+            return false
+        }
+
+        val token = Binder.clearCallingIdentity()
+        try {
+            if (permissionName == Manifest.permission.ACCESS_BACKGROUND_LOCATION &&
+                platformCompat.isChangeEnabledByPackageName(
+                    BACKGROUND_RATIONALE_CHANGE_ID, packageName, userId)
+            ) {
+                return true
+            }
+        } catch (e: RemoteException) {
+            Log.e(LOG_TAG, "Unable to check if compatibility change is enabled.", e)
+        } finally {
+            Binder.restoreCallingIdentity(token)
+        }
+
+        return permissionFlags and PackageManager.FLAG_PERMISSION_USER_SET != 0
+    }
+
+    /**
+     * read internal permission flags
+     * @return internal permission Flags
+     * @see PermissionFlags
+     */
+    private fun getPermissionFlagsInternal(
+        packageName: String,
+        permName: String,
+        callingUid: Int,
+        userId: Int
+    ): Int {
+        throw NotImplementedError()
     }
 
     override fun updatePermissionFlags(
@@ -327,7 +508,9 @@ class PermissionService(
     }
 
     override fun getSplitPermissions(): List<SplitPermissionInfoParcelable> {
-        TODO("Not yet implemented")
+        return PermissionManager.splitPermissionInfoListToParcelableList(
+            SystemConfig.getInstance().splitPermissions
+        )
     }
 
     override fun getAppOpPermissionPackages(permissionName: String): Array<String> {
@@ -335,7 +518,22 @@ class PermissionService(
     }
 
     override fun getAllAppOpPermissionPackages(): Map<String, Set<String>> {
-        TODO("Not yet implemented")
+        val appOpPermissionPackageNames = IndexedMap<String, IndexedSet<String>>()
+        val permissions = service.getState { with(policy) { getPermissions() } }
+        packageManagerLocal.withUnfilteredSnapshot().use { snapshot ->
+            snapshot.packageStates.forEach packageStates@{ (_, packageState) ->
+                val androidPackage = packageState.androidPackage ?: return@packageStates
+                androidPackage.requestedPermissions.forEach requestedPermissions@{ permissionName ->
+                    val permission = permissions[permissionName] ?: return@requestedPermissions
+                    if (permission.isAppOp) {
+                        val packageNames = appOpPermissionPackageNames
+                            .getOrPut(permissionName) { IndexedSet() }
+                        packageNames += androidPackage.packageName
+                    }
+                }
+            }
+        }
+        return appOpPermissionPackageNames
     }
 
     override fun getGidsForUid(uid: Int): IntArray {
@@ -468,6 +666,28 @@ class PermissionService(
         }
     }
 
+
+    /**
+     * This method should typically only be used when granting or revoking permissions, since the
+     * app may immediately restart after this call.
+     *
+     * If you're doing surgery on app code/data, use [PackageFreezer] to guard your work against
+     * the app being relaunched.
+     */
+    private fun killUid(appId: Int, userId: Int, reason: String) {
+        val activityManager = ActivityManager.getService()
+        if (activityManager != null) {
+            val identity = Binder.clearCallingIdentity()
+            try {
+                activityManager.killUidForPermissionChange(appId, userId, reason)
+            } catch (e: RemoteException) {
+                /* ignore - same process */
+            } finally {
+                Binder.restoreCallingIdentity(identity)
+            }
+        }
+    }
+
     /**
      * Check whether a UID belongs to an instant app.
      */
@@ -504,4 +724,133 @@ class PermissionService(
         val user = UserHandle.of(userId)
         return filtered(uid, user).use { it.getPackageState(packageName) != null }
     }
+
+    /**
+     * Callback invoked when interesting actions have been taken on a permission.
+     */
+    private inner class OnPermissionFlagsChangedListener :
+        UidPermissionPolicy.OnPermissionFlagsChangedListener {
+        override fun onPermissionFlagsChanged(
+            appId: Int,
+            userId: Int,
+            permissionName: String,
+            oldFlags: Int,
+            newFlags: Int
+        ) {
+            val uid = UserHandle.getUid(userId, appId)
+            val permission = service.getState {
+                with(policy) { getPermissions()[permissionName] }
+            } ?: return
+
+            val isPermissionGranted = !PermissionFlags.isPermissionGranted(oldFlags) &&
+                PermissionFlags.isPermissionGranted(newFlags)
+            val isPermissionRevoked = PermissionFlags.isPermissionGranted(oldFlags) &&
+                !PermissionFlags.isPermissionGranted(newFlags)
+
+            if (isPermissionGranted) {
+                if (permission.isRuntime) {
+                    onPermissionsChangeListeners.onPermissionsChanged(uid)
+                }
+                handler.post {
+                    if (permission.hasGids) {
+                        killUid(appId, userId, PermissionManager.KILL_APP_REASON_GIDS_CHANGED)
+                    }
+                }
+            } else if (isPermissionRevoked) {
+                // TODO: STOPSHIP skip kill for revokePostNotificationPermissionWithoutKillForTest
+                if (permission.isRuntime) {
+                    onPermissionsChangeListeners.onPermissionsChanged(uid)
+                    handler.post {
+                        if (!(permissionName == Manifest.permission.POST_NOTIFICATIONS &&
+                            isAppBackupAndRestoreRunning(uid))) {
+                            killUid(
+                                appId, userId, PermissionManager.KILL_APP_REASON_PERMISSIONS_REVOKED
+                            )
+                        }
+                    }
+                }
+            } else if (oldFlags != newFlags) {
+                onPermissionsChangeListeners.onPermissionsChanged(uid)
+            }
+        }
+
+        private fun isAppBackupAndRestoreRunning(uid: Int): Boolean {
+            if (checkUidPermission(uid, Manifest.permission.BACKUP) !=
+                PackageManager.PERMISSION_GRANTED) {
+                return false
+            }
+            return try {
+                val userId = UserHandle.getUserId(uid)
+                val isInSetup = Settings.Secure.getIntForUser(
+                    context.contentResolver, Settings.Secure.USER_SETUP_COMPLETE, userId
+                ) == 0
+                val isInDeferredSetup = Settings.Secure.getIntForUser(
+                    context.contentResolver,
+                    Settings.Secure.USER_SETUP_PERSONALIZATION_STATE, userId
+                ) == Settings.Secure.USER_SETUP_PERSONALIZATION_STARTED
+                isInSetup || isInDeferredSetup
+            } catch (e: Settings.SettingNotFoundException) {
+                Log.w(LOG_TAG, "Failed to check if the user is in restore: $e")
+                false
+            }
+        }
+    }
+
+    private class OnPermissionsChangeListeners(looper: Looper) : Handler(looper) {
+        private val listeners = RemoteCallbackList<IOnPermissionsChangeListener>()
+
+        override fun handleMessage(msg: Message) {
+            when (msg.what) {
+                MSG_ON_PERMISSIONS_CHANGED -> {
+                    val uid = msg.arg1
+                    handleOnPermissionsChanged(uid)
+                }
+            }
+        }
+
+        private fun handleOnPermissionsChanged(uid: Int) {
+            val count = listeners.beginBroadcast()
+            try {
+                for (i in 0 until count) {
+                    val callback = listeners.getBroadcastItem(i)
+                    try {
+                        callback.onPermissionsChanged(uid)
+                    } catch (e: RemoteException) {
+                        Log.e(LOG_TAG, "Permission listener is dead", e)
+                    }
+                }
+            } finally {
+                listeners.finishBroadcast()
+            }
+        }
+
+        fun addListener(listener: IOnPermissionsChangeListener) {
+            listeners.register(listener)
+        }
+
+        fun removeListener(listener: IOnPermissionsChangeListener) {
+            listeners.unregister(listener)
+        }
+
+        fun onPermissionsChanged(uid: Int) {
+            if (listeners.registeredCallbackCount > 0) {
+                obtainMessage(MSG_ON_PERMISSIONS_CHANGED, uid, 0).sendToTarget()
+            }
+        }
+        companion object {
+            private const val MSG_ON_PERMISSIONS_CHANGED = 1
+        }
+    }
+
+    companion object {
+        private val LOG_TAG = PermissionService::class.java.simpleName
+
+        /**
+         * This change makes it so that apps are told to show rationale for asking for background
+         * location access every time they request.
+         */
+        @ChangeId
+        @EnabledAfter(targetSdkVersion = Build.VERSION_CODES.Q)
+        private val BACKGROUND_RATIONALE_CHANGE_ID = 147316723L
+    }
 }
diff --git a/services/permission/java/com/android/server/permission/access/permission/UidPermissionPolicy.kt b/services/permission/java/com/android/server/permission/access/permission/UidPermissionPolicy.kt
index b2f52cc814cb..022d966f1304 100644
--- a/services/permission/java/com/android/server/permission/access/permission/UidPermissionPolicy.kt
+++ b/services/permission/java/com/android/server/permission/access/permission/UidPermissionPolicy.kt
@@ -829,11 +829,17 @@ class UidPermissionPolicy : SchemePolicy() {
         with(persistence) { this@serializeSystemState.serializeSystemState(systemState) }
     }
 
-    fun GetStateScope.getPermissionGroup(permissionGroupName: String): PermissionGroupInfo? =
-        state.systemState.permissionGroups[permissionGroupName]
+    /**
+     * returns all permission group definitions available in the system
+     */
+    fun GetStateScope.getPermissionGroups(): IndexedMap<String, PermissionGroupInfo> =
+        state.systemState.permissionGroups
 
-    fun GetStateScope.getPermission(permissionName: String): Permission? =
-        state.systemState.permissions[permissionName]
+    /**
+     * returns all permission definitions available in the system
+     */
+    fun GetStateScope.getPermissions(): IndexedMap<String, Permission> =
+        state.systemState.permissions
 
     fun GetStateScope.getUidPermissionFlags(appId: Int, userId: Int): IndexedMap<String, Int>? =
         state.userStates[userId]?.uidPermissionFlags?.get(appId)