| /* |
| * Copyright (C) 2019 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.internal.net.eap.message.simaka; |
| |
| import static com.android.internal.net.eap.message.simaka.EapSimAkaAttribute.EAP_AT_KDF; |
| import static com.android.internal.net.eap.message.simaka.EapSimAkaAttribute.EAP_AT_KDF_INPUT; |
| import static com.android.internal.net.eap.message.simaka.EapSimAkaAttribute.LENGTH_SCALING; |
| |
| import com.android.internal.net.eap.exceptions.simaka.EapSimAkaInvalidAttributeException; |
| import com.android.internal.net.eap.exceptions.simaka.EapSimAkaUnsupportedAttributeException; |
| import com.android.internal.net.eap.message.simaka.EapSimAkaAttribute.AtKdf; |
| import com.android.internal.net.eap.message.simaka.EapSimAkaAttribute.AtKdfInput; |
| |
| import java.nio.ByteBuffer; |
| |
| /** |
| * EapAkaPrimeAttributeFactory is used for creating EAP-AKA' attributes according to their type. |
| * |
| * @see <a href="https://tools.ietf.org/html/rfc5448">RFC 5448, Improved Extensible Authentication |
| * Protocol Method for 3rd Generation Authentication and Key Agreement (EAP-AKA')</a> |
| * @see <a href="https://www.iana.org/assignments/eap-numbers/eap-numbers.xhtml">EAP SIM/AKA |
| * Attributes</a> |
| */ |
| public class EapAkaPrimeAttributeFactory extends EapAkaAttributeFactory { |
| private static EapAkaPrimeAttributeFactory sInstance = new EapAkaPrimeAttributeFactory(); |
| |
| private EapAkaPrimeAttributeFactory() {} |
| |
| public static EapAkaPrimeAttributeFactory getInstance() { |
| return sInstance; |
| } |
| |
| /** |
| * Decodes a single EapSimAkaAttribute object from the given ByteBuffer. |
| * |
| * <p>Decoding logic is based on Attribute definitions in RFC 5448#10. |
| * |
| * @param byteBuffer The ByteBuffer to parse the current attribute from |
| * @return The current EapSimAkaAttribute to be parsed, or EapSimAkaUnsupportedAttribute if the |
| * given attributeType is skippable and unsupported |
| * @throws EapSimAkaInvalidAttributeException when a malformatted attribute is attempted to be |
| * decoded |
| * @throws EapSimAkaUnsupportedAttributeException when an unsupported, unskippable Attribute is |
| * attempted to be decoded |
| */ |
| @Override |
| public EapSimAkaAttribute getAttribute(ByteBuffer byteBuffer) |
| throws EapSimAkaInvalidAttributeException, EapSimAkaUnsupportedAttributeException { |
| int attributeType = Byte.toUnsignedInt(byteBuffer.get()); |
| |
| // Length is given as a multiple of 4x bytes (RFC 4187#8.1) |
| int lengthInBytes = Byte.toUnsignedInt(byteBuffer.get()) * LENGTH_SCALING; |
| |
| switch (attributeType) { |
| case EAP_AT_KDF_INPUT: |
| return new AtKdfInput(lengthInBytes, byteBuffer); |
| case EAP_AT_KDF: |
| return new AtKdf(lengthInBytes, byteBuffer); |
| default: |
| return super.getAttribute(attributeType, lengthInBytes, byteBuffer); |
| } |
| } |
| } |