1/*
2 * Copyright (C) 2016 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.server.wifi.hotspot2.anqp;
18
19import java.io.ByteArrayOutputStream;
20import java.io.IOException;
21
22/**
23 * Utility class for formatting IEI (Information Element Identity) data for testing.
24 */
25public class CellularNetworkTestUtil {
26    /**
27     * Format and return PLMN List IEI with the given PLMN list data.
28     *
29     * @param plmnList The array of PLMN data
30     * @return byte[]
31     * @throws IOException
32     */
33    public static byte[] formatPLMNListIEI(byte[][] plmnList) throws IOException {
34        return formatPLMNListIEI(CellularNetwork.IEI_TYPE_PLMN_LIST, plmnList);
35    }
36
37    /**
38     * Format and return PLMN List IEI with the given IEI type and PLMN list data.  This
39     * allows the test to use an invalid IEI type for testing purpose.
40     *
41     * @param ieiType The IEI type
42     * @param plmnList The array of PLMN data
43     * @return byte[]
44     * @throws IOException
45     */
46    public static byte[] formatPLMNListIEI(int ieiType, byte[][] plmnList) throws IOException {
47        return formatPLMNListIEI(ieiType, plmnList, false);
48    }
49
50    /**
51     * Format and return PLMN List IEI with the given IEI type and PLMN list data.  This also
52     * allows the test to intentionally setting an incorrect size value.
53     *
54     * @param ieiType The IEI type
55     * @param plmnList The array of PLMN data
56     * @param setWrongSize Flag for setting incorrect IEI size
57     * @return byte[]
58     * @throws IOException
59     */
60    public static byte[] formatPLMNListIEI(int ieiType, byte[][] plmnList, boolean setWrongSize)
61            throws IOException {
62        ByteArrayOutputStream stream = new ByteArrayOutputStream();
63
64        // Calculate the total bytes for all the PLMNs.
65        int plmnsSize = getDataSize(plmnList);
66
67        // Use incorrect size intentionally.
68        if (setWrongSize) plmnsSize -= 1;
69
70        stream.write((byte) ieiType);
71        // One extra byte for the PLMN count field.
72        stream.write((byte) ((plmnsSize + 1) & CellularNetwork.IEI_CONTENT_LENGTH_MASK));
73        stream.write((byte) plmnList.length);
74        for (byte[] plmn : plmnList) {
75            stream.write(plmn);
76        }
77
78        return stream.toByteArray();
79    }
80
81    /**
82     * Return the number of bytes in a 2D array.
83     *
84     * @param dataArray The 2D array
85     * @return The number of bytes in the 2D array
86     */
87    public static int getDataSize(byte[][] dataArray) {
88        int size = 0;
89        for (byte[] data : dataArray) {
90            size += data.length;
91        }
92        return size;
93    }
94}
95