From 599ef0e3cd848bbf8faa45147ac680d04d3ba333 Mon Sep 17 00:00:00 2001
From: Jim Miller <jaggies@google.com>
Date: Mon, 15 Jun 2015 20:39:44 -0700
Subject: [PATCH] Limit number of fingerprint templates that can be enrolled
 per device user

This change places an upper limit on the number of fingerprint templates that
can be enrolled per account.  This is done primarily for performance reasons, but
may also be imposed by hardware and Trusted Execution Environment (TEE) reasons.

Fixes bug 20731847

Change-Id: I5bc337698bef682cdf67940906d24842e1dffc28
---
 core/res/res/values/config.xml                |  3 +++
 core/res/res/values/symbols.xml               |  3 +++
 .../fingerprint/FingerprintService.java       | 22 ++++++++++++++-----
 3 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/core/res/res/values/config.xml b/core/res/res/values/config.xml
index e7811df1041af..997f995dcf525 100755
--- a/core/res/res/values/config.xml
+++ b/core/res/res/values/config.xml
@@ -2196,6 +2196,9 @@
     <!-- Keyguard component -->
     <string name="config_keyguardComponent" translatable="false">com.android.systemui/com.android.systemui.keyguard.KeyguardService</string>
 
+    <!-- For performance and storage reasons, limit the number of fingerprints per user -->
+    <integer name="config_fingerprintMaxTemplatesPerUser">5</integer>
+
     <!-- This config is used to force VoiceInteractionService to start on certain low ram devices.
          It declares the package name of VoiceInteractionService that should be started. -->
     <string translatable="false" name="config_forceVoiceInteractionServicePackage"></string>
diff --git a/core/res/res/values/symbols.xml b/core/res/res/values/symbols.xml
index 45e5d17b32187..ede843ec90b6b 100755
--- a/core/res/res/values/symbols.xml
+++ b/core/res/res/values/symbols.xml
@@ -2125,6 +2125,9 @@
   <java-symbol type="string" name="fingerprint_error_lockout" />
   <java-symbol type="string" name="fingerprint_name_template" />
 
+  <!-- Fingerprint config -->
+  <java-symbol type="integer" name="config_fingerprintMaxTemplatesPerUser"/>
+
   <!-- From various Material changes -->
   <java-symbol type="attr" name="titleTextAppearance" />
   <java-symbol type="attr" name="subtitleTextAppearance" />
diff --git a/services/core/java/com/android/server/fingerprint/FingerprintService.java b/services/core/java/com/android/server/fingerprint/FingerprintService.java
index 7f0be5766d1a7..c52a1c1ce6db8 100644
--- a/services/core/java/com/android/server/fingerprint/FingerprintService.java
+++ b/services/core/java/com/android/server/fingerprint/FingerprintService.java
@@ -33,6 +33,7 @@ import android.os.MessageQueue;
 import android.os.RemoteException;
 import android.os.SELinux;
 import android.os.ServiceManager;
+import android.os.UserHandle;
 import android.util.Slog;
 
 import com.android.server.SystemService;
@@ -389,12 +390,12 @@ public class FingerprintService extends SystemService implements IBinder.DeathRe
         }
     }
 
-    public List<Fingerprint> getEnrolledFingerprints(int groupId) {
-        return mFingerprintUtils.getFingerprintsForUser(mContext, groupId);
+    public List<Fingerprint> getEnrolledFingerprints(int userId) {
+        return mFingerprintUtils.getFingerprintsForUser(mContext, userId);
     }
 
-    public boolean hasEnrolledFingerprints(int groupId) {
-        return mFingerprintUtils.getFingerprintsForUser(mContext, groupId).size() > 0;
+    public boolean hasEnrolledFingerprints(int userId) {
+        return mFingerprintUtils.getFingerprintsForUser(mContext, userId).size() > 0;
     }
 
     boolean hasPermission(String permission) {
@@ -598,6 +599,15 @@ public class FingerprintService extends SystemService implements IBinder.DeathRe
         public void enroll(final IBinder token, final byte[] cryptoToken, final int groupId,
                 final IFingerprintServiceReceiver receiver, final int flags) {
             checkPermission(MANAGE_FINGERPRINT);
+            final int limit =  mContext.getResources().getInteger(
+                    com.android.internal.R.integer.config_fingerprintMaxTemplatesPerUser);
+            final int callingUid = Binder.getCallingUid();
+            final int userId = UserHandle.getUserId(callingUid);
+            final int enrolled = FingerprintService.this.getEnrolledFingerprints(userId).size();
+            if (enrolled >= limit) {
+                Slog.w(TAG, "Too many fingerprints registered");
+                return;
+            }
             final byte [] cryptoClone = Arrays.copyOf(cryptoToken, cryptoToken.length);
 
             final boolean restricted = isRestricted();
@@ -689,11 +699,11 @@ public class FingerprintService extends SystemService implements IBinder.DeathRe
         }
 
         @Override // Binder call
-        public List<Fingerprint> getEnrolledFingerprints(int groupId, String opPackageName) {
+        public List<Fingerprint> getEnrolledFingerprints(int userId, String opPackageName) {
             if (!canUseFingerprint(opPackageName)) {
                 return Collections.emptyList();
             }
-            return FingerprintService.this.getEnrolledFingerprints(groupId);
+            return FingerprintService.this.getEnrolledFingerprints(userId);
         }
 
         @Override // Binder call