| /* |
| * Copyright (C) 2006 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.telephony.gsm; |
| |
| /** |
| * SIM Tag-Length-Value record |
| * TS 102 223 Annex C |
| * |
| * {@hide} |
| * |
| */ |
| public class SimTlv |
| { |
| //***** Private Instance Variables |
| |
| byte mRecord[]; |
| int mTlvOffset; |
| int mTlvLength; |
| int mCurOffset; |
| int mCurDataOffset; |
| int mCurDataLength; |
| boolean mHasValidTlvObject; |
| |
| public SimTlv(byte[] record, int offset, int length) { |
| mRecord = record; |
| |
| mTlvOffset = offset; |
| mTlvLength = length; |
| mCurOffset = offset; |
| |
| mHasValidTlvObject = parseCurrentTlvObject(); |
| } |
| |
| public boolean nextObject() { |
| if (!mHasValidTlvObject) return false; |
| mCurOffset = mCurDataOffset + mCurDataLength; |
| mHasValidTlvObject = parseCurrentTlvObject(); |
| return mHasValidTlvObject; |
| } |
| |
| public boolean isValidObject() { |
| return mHasValidTlvObject; |
| } |
| |
| /** |
| * Returns the tag for the current TLV object |
| * Return 0 if !isValidObject() |
| * 0 and 0xff are invalid tag values |
| * valid tags range from 1 - 0xfe |
| */ |
| public int getTag() { |
| if (!mHasValidTlvObject) return 0; |
| return mRecord[mCurOffset] & 0xff; |
| } |
| |
| /** |
| * Returns data associated with current TLV object |
| * returns null if !isValidObject() |
| */ |
| |
| public byte[] getData() { |
| if (!mHasValidTlvObject) return null; |
| |
| byte[] ret = new byte[mCurDataLength]; |
| System.arraycopy(mRecord, mCurDataOffset, ret, 0, mCurDataLength); |
| return ret; |
| } |
| |
| /** |
| * Updates curDataLength and curDataOffset |
| * @return false on invalid record, true on valid record |
| */ |
| |
| private boolean parseCurrentTlvObject() { |
| // 0x00 and 0xff are invalid tag values |
| |
| try { |
| if (mRecord[mCurOffset] == 0 || (mRecord[mCurOffset] & 0xff) == 0xff) { |
| return false; |
| } |
| |
| if ((mRecord[mCurOffset + 1] & 0xff) < 0x80) { |
| // one byte length 0 - 0x7f |
| mCurDataLength = mRecord[mCurOffset + 1] & 0xff; |
| mCurDataOffset = mCurOffset + 2; |
| } else if ((mRecord[mCurOffset + 1] & 0xff) == 0x81) { |
| // two byte length 0x80 - 0xff |
| mCurDataLength = mRecord[mCurOffset + 2] & 0xff; |
| mCurDataOffset = mCurOffset + 3; |
| } else { |
| return false; |
| } |
| } catch (ArrayIndexOutOfBoundsException ex) { |
| return false; |
| } |
| |
| if (mCurDataLength + mCurDataOffset > mTlvOffset + mTlvLength) { |
| return false; |
| } |
| |
| return true; |
| } |
| |
| } |