From fa265ed97026e3b8675a2ccbf4035cad6dc1523f Mon Sep 17 00:00:00 2001
From: Guliz Tuncay <gulizseray@google.com>
Date: Wed, 16 Aug 2017 12:02:31 -0700
Subject: [PATCH] Select only preinstalled Spell Checker Services

When we are setting a new spell checker as the default one in
Secure.Settings, TSMS#findAvailSpellCheckerLocked can pick up
any available spell checker service. This violates the principle
that user should be warned whenever we are setting an untrusted
spell checker service as the default service, since the warning
dialog is never shown.

Fixes: 64764051
Bug: 118694079
Test: Manually as follows:
0. Make sure AOSP keyboard is pre-installed.
1. adb shell settings put --user 0 secure selected_spell_checker com.android.inputmethod.latin/.spellcheck.AndroidSpellCheckerService
2. tapas SampleSpellCheckerService
3. make -j
4. adb install --user 0  -r out/target/product/generic/system/app/SampleSpellCheckerService/SampleSpellCheckerService.apk
5. adb shell pm disable com.android.inputmethod.latin
6. adb shell settings get --user 0 secure selected_spell_checker
    -> com.android.inputmethod.latin/.spellcheck.AndroidSpellCheckerService
7. adb reboot
8. adb shell settings get --user 0 secure selected_spell_checker
    -> com.android.inputmethod.latin/.spellcheck.AndroidSpellCheckerService
Change-Id: I298ffbcfa5e32f43753f54fbebc40a414a5c0f9e
Merged-In: I298ffbcfa5e32f43753f54fbebc40a414a5c0f9e
---
 .../android/server/TextServicesManagerService.java   | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/services/core/java/com/android/server/TextServicesManagerService.java b/services/core/java/com/android/server/TextServicesManagerService.java
index 4b0d4be11b14..14fe6a271434 100644
--- a/services/core/java/com/android/server/TextServicesManagerService.java
+++ b/services/core/java/com/android/server/TextServicesManagerService.java
@@ -183,7 +183,7 @@ public class TextServicesManagerService extends ITextServicesManager.Stub {
         buildSpellCheckerMapLocked(mContext, mSpellCheckerList, mSpellCheckerMap, mSettings);
         SpellCheckerInfo sci = getCurrentSpellChecker(null);
         if (sci == null) {
-            sci = findAvailSpellCheckerLocked(null);
+            sci = findAvailSystemSpellCheckerLocked(null);
             if (sci != null) {
                 // Set the current spell checker if there is one or more spell checkers
                 // available. In this case, "sci" is the first one in the available spell
@@ -227,7 +227,7 @@ public class TextServicesManagerService extends ITextServicesManager.Stub {
                         change == PACKAGE_PERMANENT_CHANGE || change == PACKAGE_TEMPORARY_CHANGE
                         // Package modified
                         || isPackageModified(packageName)) {
-                    sci = findAvailSpellCheckerLocked(packageName);
+                    sci = findAvailSystemSpellCheckerLocked(packageName);
                     if (sci != null) {
                         setCurrentSpellCheckerLocked(sci.getId());
                     }
@@ -371,8 +371,16 @@ public class TextServicesManagerService extends ITextServicesManager.Stub {
         mSpellCheckerBindGroups.clear();
     }
 
-    private SpellCheckerInfo findAvailSpellCheckerLocked(String prefPackage) {
-        final int spellCheckersCount = mSpellCheckerList.size();
+    private SpellCheckerInfo findAvailSystemSpellCheckerLocked(String prefPackage) {
+        // Filter the spell checker list to remove spell checker services that are not pre-installed
+        ArrayList<SpellCheckerInfo> spellCheckerList = new ArrayList<>();
+        for (SpellCheckerInfo sci : mSpellCheckerList) {
+            if ((sci.getServiceInfo().applicationInfo.flags & ApplicationInfo.FLAG_SYSTEM) != 0) {
+                spellCheckerList.add(sci);
+            }
+        }
+
+        final int spellCheckersCount = spellCheckerList.size();
         if (spellCheckersCount == 0) {
             Slog.w(TAG, "no available spell checker services found");
             return null;
@@ -382,7 +390,7 @@ public class TextServicesManagerService extends ITextServicesManager.Stub {
                 final SpellCheckerInfo sci = mSpellCheckerList.get(i);
                 if (prefPackage.equals(sci.getPackageName())) {
                     if (DBG) {
-                        Slog.d(TAG, "findAvailSpellCheckerLocked: " + sci.getPackageName());
+                        Slog.d(TAG, "findAvailSystemSpellCheckerLocked: " + sci.getPackageName());
                     }
                     return sci;
                 }
@@ -396,7 +404,7 @@ public class TextServicesManagerService extends ITextServicesManager.Stub {
         final ArrayList<Locale> suitableLocales =
                 InputMethodUtils.getSuitableLocalesForSpellChecker(systemLocal);
         if (DBG) {
-            Slog.w(TAG, "findAvailSpellCheckerLocked suitableLocales="
+            Slog.w(TAG, "findAvailSystemSpellCheckerLocked suitableLocales="
                     + Arrays.toString(suitableLocales.toArray(new Locale[suitableLocales.size()])));
         }
         final int localeCount = suitableLocales.size();
-- 
2.11.0