/****************************************************************************
* Amazon Modifications: Copyright 2016 Amazon.com, Inc. or its affiliates.
* All Rights Reserved.
*****************************************************************************
* Copyright (c) 1998-2010 AOL Inc.
*
* 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.
*
****************************************************************************/
// http://oauth.googlecode.com/svn/code/branches/jmeter/jmeter/src/main/java/org/apache/jmeter/protocol/oauth/sampler/PrivateKeyReader.java
package com.amazonaws.mobileconnectors.iot;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.math.BigInteger;
/**
* A bare-minimum ASN.1 DER decoder, just having enough functions to decode
* PKCS#1 private keys. Especially, it doesn't handle explicitly tagged types
* with an outer tag. This parser can only handle one layer. To parse nested
* constructs, get a new parser for each layer using
* <code>Asn1Object.getParser()</code>. There are many DER decoders in JRE but
* using them will tie this program to a specific JCE/JVM.
*/
class DerParser {
// Classes
/** UNIVERSAL class. */
public static final int UNIVERSAL = 0x00;
/** APPLICATION class. */
public static final int APPLICATION = 0x40;
/** CONTEXT class. */
public static final int CONTEXT = 0x80;
/** PRIVATE class. */
public static final int PRIVATE = 0xC0;
/** Constructed Flag. */
public static final int CONSTRUCTED = 0x20;
// Tag and data types
/** ANY tag/type. */
public static final int ANY = 0x00;
/** BOOLEAN tag/type. */
public static final int BOOLEAN = 0x01;
/** INTEGER tag/type. */
public static final int INTEGER = 0x02;
/** BIT_STRING tag/type. */
public static final int BIT_STRING = 0x03;
/** OCTET_STRING tag/type. */
public static final int OCTET_STRING = 0x04;
/** NULL tag/type. */
public static final int NULL = 0x05;
/** OBJECT_IDENTIFIER tag/type. */
public static final int OBJECT_IDENTIFIER = 0x06;
/** REAL tag/type. */
public static final int REAL = 0x09;
/** ENUMERATED tag/type. */
public static final int ENUMERATED = 0x0a;
/** RELATIVE_OID tag/type. */
public static final int RELATIVE_OID = 0x0d;
/** v tag/type. */
public static final int SEQUENCE = 0x10;
/** SET tag/type. */
public static final int SET = 0x11;
/** NUMERIC_STRING tag/type. */
public static final int NUMERIC_STRING = 0x12;
/** PRINTABLE_STRING tag/type. */
public static final int PRINTABLE_STRING = 0x13;
/** T61_STRING tag/type. */
public static final int T61_STRING = 0x14;
/** VIDEOTEX_STRING tag/type. */
public static final int VIDEOTEX_STRING = 0x15;
/** IA5_STRING tag/type. */
public static final int IA5_STRING = 0x16;
/** GRAPHIC_STRING tag/type. */
public static final int GRAPHIC_STRING = 0x19;
/** ISO646_STRING tag/type. */
public static final int ISO646_STRING = 0x1A;
/** GENERAL_STRING tag/type. */
public static final int GENERAL_STRING = 0x1B;
/** UTF8_STRING tag/type. */
public static final int UTF8_STRING = 0x0C;
/** UNIVERSAL_STRING tag/type. */
public static final int UNIVERSAL_STRING = 0x1C;
/** BMP_STRING tag/type. */
public static final int BMP_STRING = 0x1E;
/** UTC_TIME tag/type. */
public static final int UTC_TIME = 0x17;
/** GENERALIZED_TIME tag/type. */
public static final int GENERALIZED_TIME = 0x18;
/** Lower 7 bits mask. */
public static final byte LOWER_7_BITS = (byte) 0x7F;
/** Byte max value. */
public static final int BYTE_MAX = (int) 0xFF;
/** We can't handle length longer than 4 bytes. */
public static final int MAX_NUMBER_OF_BYTES = 4;
/** The DER encoded input stream. */
private final InputStream in;
/**
* Create a new DER decoder from an input stream.
*
* @param in DER encoded stream
*/
public DerParser(InputStream in) {
this.in = in;
}
/**
* Create a new DER decoder from a byte array.
*
* @param bytes encoded bytes
*/
public DerParser(byte[] bytes) {
this(new ByteArrayInputStream(bytes));
}
/**
* Read next object. If it's constructed, the value holds encoded content
* and it should be parsed by a new parser from
* <code>Asn1Object.getParser</code>.
*
* @return Asn1Object read
* @throws IOException if DER parsing error (format).
*/
public Asn1Object read() throws IOException {
int tag = in.read();
if (tag == -1) {
throw new IOException("Invalid DER: stream too short, missing tag"); //$NON-NLS-1$
}
int length = getLength();
byte[] value = new byte[length];
int n = in.read(value);
if (n < length) {
throw new IOException("Invalid DER: stream too short, missing value"); //$NON-NLS-1$
}
Asn1Object o = new Asn1Object(tag, length, value);
return o;
}
/**
* Decode the length of the field. Can only support length encoding up to 4
* octets.
* <p/>
* In BER/DER encoding, length can be encoded in 2 forms,
* <ul>
* <li>Short form. One octet. Bit 8 has value "0" and bits 7-1 give the
* length.
* <li>Long form. Two to 127 octets (only 4 is supported here). Bit 8 of
* first octet has value "1" and bits 7-1 give the number of additional
* length octets. Second and following octets give the length, base 256,
* most significant digit first.
* </ul>
*
* @return The length as integer
* @throws IOException if invalid DER.
*/
private int getLength() throws IOException {
int i = in.read();
if (i == -1) {
throw new IOException("Invalid DER: length missing"); //$NON-NLS-1$
}
// A single byte short length
if ((i & ~LOWER_7_BITS) == 0) {
return i;
}
int num = i & LOWER_7_BITS;
if (i >= BYTE_MAX || num > MAX_NUMBER_OF_BYTES) {
throw new IOException("Invalid DER: length field too big (" + i + ")"); //$NON-NLS-1$
}
byte[] bytes = new byte[num];
int n = in.read(bytes);
if (n < num) {
throw new IOException("Invalid DER: length too short"); //$NON-NLS-1$
}
return new BigInteger(1, bytes).intValue();
}
}