[FUI21.1] Create NetworkIdentityUtils class

This patch creates a class in the static lib that contains utils
of NetworkIdentity.

Test: atest NetworkIdentityUtilsTest
Bug: 174123988
Change-Id: I6f0780190017b5eef3312b764107ac1f00e06833

1 files changed, 51 insertions, 0 deletions

diff --git a/common/framework/com/android/net/module/util/NetworkIdentityUtils.java b/common/framework/com/android/net/module/util/NetworkIdentityUtils.java
new file mode 100644
index 00000000..94e60178
--- /dev/null
+++ b/common/framework/com/android/net/module/util/NetworkIdentityUtils.java
@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.net.module.util;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+
+/**
+ * Utilities to examine {@link android.net.NetworkIdentity}.
+ */
+public class NetworkIdentityUtils {
+    /**
+     * Scrub given IMSI on production builds.
+     */
+    @NonNull
+    public static String scrubSubscriberId(@Nullable String subscriberId) {
+        if (subscriberId != null) {
+            // TODO: parse this as MCC+MNC instead of hard-coding
+            return subscriberId.substring(0, Math.min(6, subscriberId.length())) + "...";
+        } else {
+            return "null";
+        }
+    }
+
+    /**
+     * Scrub given IMSI on production builds.
+     */
+    @Nullable
+    public static String[] scrubSubscriberIds(@Nullable String[] subscriberIds) {
+        if (subscriberIds == null) return null;
+        final String[] res = new String[subscriberIds.length];
+        for (int i = 0; i < res.length; i++) {
+            res[i] = scrubSubscriberId(subscriberIds[i]);
+        }
+        return res;
+    }
+}