| /* |
| * Copyright (C) 2014 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.nfc; |
| |
| |
| import android.app.ActivityManager; |
| import android.content.Context; |
| import android.content.Intent; |
| import android.net.wifi.WifiConfiguration; |
| import android.nfc.NdefMessage; |
| import android.nfc.NdefRecord; |
| import android.nfc.tech.Ndef; |
| import android.os.UserHandle; |
| import android.os.UserManager; |
| import android.util.Log; |
| |
| import java.nio.BufferUnderflowException; |
| import java.nio.ByteBuffer; |
| import java.util.Arrays; |
| import java.util.BitSet; |
| |
| public final class NfcWifiProtectedSetup { |
| |
| public static final String NFC_TOKEN_MIME_TYPE = "application/vnd.wfa.wsc"; |
| |
| public static final String EXTRA_WIFI_CONFIG = "com.android.nfc.WIFI_CONFIG_EXTRA"; |
| |
| /* |
| * ID into configuration record for SSID and Network Key in hex. |
| * Obtained from WFA Wifi Simple Configuration Technical Specification v2.0.2.1. |
| */ |
| private static final short CREDENTIAL_FIELD_ID = 0x100E; |
| private static final short SSID_FIELD_ID = 0x1045; |
| private static final short NETWORK_KEY_FIELD_ID = 0x1027; |
| private static final short AUTH_TYPE_FIELD_ID = 0x1003; |
| |
| private static final short AUTH_TYPE_EXPECTED_SIZE = 2; |
| |
| private static final short AUTH_TYPE_OPEN = 0x0001; |
| private static final short AUTH_TYPE_WPA_PSK = 0x0002; |
| private static final short AUTH_TYPE_WPA_EAP = 0x0008; |
| private static final short AUTH_TYPE_WPA2_EAP = 0x0010; |
| private static final short AUTH_TYPE_WPA2_PSK = 0x0020; |
| |
| private static final int MAX_NETWORK_KEY_SIZE_BYTES = 64; |
| |
| private NfcWifiProtectedSetup() {} |
| |
| public static boolean tryNfcWifiSetup(Ndef ndef, Context context) { |
| |
| if (ndef == null || context == null) { |
| return false; |
| } |
| |
| NdefMessage cachedNdefMessage = ndef.getCachedNdefMessage(); |
| if (cachedNdefMessage == null) { |
| return false; |
| } |
| |
| final WifiConfiguration wifiConfiguration; |
| try { |
| wifiConfiguration = parse(cachedNdefMessage); |
| } catch (BufferUnderflowException e) { |
| // malformed payload |
| return false; |
| } |
| |
| if (wifiConfiguration != null &&!UserManager.get(context).hasUserRestriction( |
| UserManager.DISALLOW_CONFIG_WIFI, |
| // hasUserRestriction does not support UserHandle.CURRENT. |
| UserHandle.of(ActivityManager.getCurrentUser()))) { |
| Intent configureNetworkIntent = new Intent() |
| .putExtra(EXTRA_WIFI_CONFIG, wifiConfiguration) |
| .setClass(context, ConfirmConnectToWifiNetworkActivity.class) |
| .setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK); |
| |
| context.startActivityAsUser(configureNetworkIntent, UserHandle.CURRENT); |
| return true; |
| } |
| |
| return false; |
| } |
| |
| private static WifiConfiguration parse(NdefMessage message) { |
| NdefRecord[] records = message.getRecords(); |
| |
| for (NdefRecord record : records) { |
| if (new String(record.getType()).equals(NFC_TOKEN_MIME_TYPE)) { |
| ByteBuffer payload = ByteBuffer.wrap(record.getPayload()); |
| while (payload.hasRemaining()) { |
| short fieldId = payload.getShort(); |
| int fieldSize = payload.getShort() & 0xFFFF; |
| if (fieldId == CREDENTIAL_FIELD_ID) { |
| return parseCredential(payload, fieldSize); |
| } |
| payload.position(payload.position() + fieldSize); |
| } |
| } |
| } |
| return null; |
| } |
| |
| private static WifiConfiguration parseCredential(ByteBuffer payload, int size) { |
| int startPosition = payload.position(); |
| WifiConfiguration result = new WifiConfiguration(); |
| while (payload.position() < startPosition + size) { |
| short fieldId = payload.getShort(); |
| int fieldSize = payload.getShort() & 0xFFFF; |
| |
| // sanity check |
| if (payload.position() + fieldSize > startPosition + size) { |
| return null; |
| } |
| |
| switch (fieldId) { |
| case SSID_FIELD_ID: |
| byte[] ssid = new byte[fieldSize]; |
| payload.get(ssid); |
| result.SSID = "\"" + new String(ssid) + "\""; |
| break; |
| case NETWORK_KEY_FIELD_ID: |
| if (fieldSize > MAX_NETWORK_KEY_SIZE_BYTES) { |
| return null; |
| } |
| byte[] networkKey = new byte[fieldSize]; |
| payload.get(networkKey); |
| if (fieldSize > 0) { |
| result.preSharedKey = "\"" + new String(networkKey) + "\""; |
| } |
| break; |
| case AUTH_TYPE_FIELD_ID: |
| if (fieldSize != AUTH_TYPE_EXPECTED_SIZE) { |
| // corrupt data |
| return null; |
| } |
| |
| short authType = payload.getShort(); |
| populateAllowedKeyManagement(result.allowedKeyManagement, authType); |
| break; |
| default: |
| // unknown / unparsed tag |
| payload.position(payload.position() + fieldSize); |
| break; |
| } |
| } |
| |
| if (result.SSID != null) { |
| if (result.getAuthType() == WifiConfiguration.KeyMgmt.NONE) { |
| if (result.preSharedKey == null) { |
| return result; |
| } |
| } else { |
| if (result.preSharedKey != null) { |
| return result; |
| } |
| } |
| } |
| |
| return null; |
| } |
| |
| private static void populateAllowedKeyManagement(BitSet allowedKeyManagement, short authType) { |
| if (authType == AUTH_TYPE_WPA_PSK || authType == AUTH_TYPE_WPA2_PSK) { |
| allowedKeyManagement.set(WifiConfiguration.KeyMgmt.WPA_PSK); |
| } else if (authType == AUTH_TYPE_WPA_EAP || authType == AUTH_TYPE_WPA2_EAP) { |
| allowedKeyManagement.set(WifiConfiguration.KeyMgmt.WPA_EAP); |
| } else if (authType == AUTH_TYPE_OPEN) { |
| allowedKeyManagement.set(WifiConfiguration.KeyMgmt.NONE); |
| } |
| } |
| } |