📄 base64.java
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/*
* The Apache Software License, Version 1.1
*
*
* Copyright (c) 1999 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Xerces" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
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*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation and was
* originally based on software copyright (c) 1999, International
* Business Machines, Inc., http://www.apache.org. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*/
package test.passwd;
import java.lang.*;
/**
* This class provides encode/decode for RFC 2045 Base64 as
* defined by RFC 2045, N. Freed and N. Borenstein.
* RFC 2045: Multipurpose Internet Mail Extensions (MIME)
* Part One: Format of Internet Message Bodies. Reference
* 1996 Available at: http://www.ietf.org/rfc/rfc2045.txt
* This class is used by XML Schema binary format validation
*
* @author Jeffrey Rodriguez
* @version $Id: Base64.java,v 1.4 2000/08/02 16:36:20 jeffreyr Exp $
*/
public final class Base64 {
static private final int BASELENGTH = 255;
static private final int LOOKUPLENGTH = 64;
static private final int TWENTYFOURBITGROUP = 24;
static private final int EIGHTBIT = 8;
static private final int SIXTEENBIT = 16;
static private final int SIXBIT = 6;
static private final int FOURBYTE = 4;
static private final int SIGN = -128;
static private final byte PAD = ( byte ) '=';
static private final boolean fDebug = false;
static private byte [] base64Alphabet = new byte[BASELENGTH];
static private byte [] lookUpBase64Alphabet = new byte[LOOKUPLENGTH];
static {
for (int i = 0; i<BASELENGTH; i++ ) {
base64Alphabet[i] = -1;
}
for ( int i = 'Z'; i >= 'A'; i-- ) {
base64Alphabet[i] = (byte) (i-'A');
}
for ( int i = 'z'; i>= 'a'; i--) {
base64Alphabet[i] = (byte) ( i-'a' + 26);
}
for ( int i = '9'; i >= '0'; i--) {
base64Alphabet[i] = (byte) (i-'0' + 52);
}
base64Alphabet['+'] = 62;
base64Alphabet['/'] = 63;
for (int i = 0; i<=25; i++ )
lookUpBase64Alphabet[i] = (byte) ('A'+i );
for (int i = 26, j = 0; i<=51; i++, j++ )
lookUpBase64Alphabet[i] = (byte) ('a'+ j );
for (int i = 52, j = 0; i<=61; i++, j++ )
lookUpBase64Alphabet[i] = (byte) ('0' + j );
lookUpBase64Alphabet[62] = (byte) '+';
lookUpBase64Alphabet[63] = (byte) '/';
}
public static boolean isBase64( String isValidString ){
return( isArrayByteBase64( isValidString.getBytes()));
}
public static boolean isBase64( byte octect ) {
//shall we ignore white space? JEFF??
return(octect == PAD || base64Alphabet[octect] != -1 );
}
public static boolean isArrayByteBase64( byte[] arrayOctect ) {
int length = arrayOctect.length;
if ( (length == 0) || (length % 4 != 0) )
return false;
boolean bEnd = false;
for ( int i=0; i < length; i++ ) {
if (arrayOctect[i] == PAD) {
bEnd = true;
continue;
}
if (bEnd || Base64.isBase64( arrayOctect[i] ) == false)
return false;
}
return true;
}
/**
* Encodes hex octects into Base64
*
* @param binaryData Array containing binaryData
* @return Encoded Base64 array
*/
public static byte[] encode( byte[] binaryData ) {
int lengthDataBits = binaryData.length*EIGHTBIT;
int fewerThan24bits = lengthDataBits%TWENTYFOURBITGROUP;
int numberTriplets = lengthDataBits/TWENTYFOURBITGROUP;
byte encodedData[] = null;
if ( fewerThan24bits != 0 ) //data not divisible by 24 bit
encodedData = new byte[ (numberTriplets + 1 )*4 ];
else // 16 or 8 bit
encodedData = new byte[ numberTriplets*4 ];
byte k=0, l=0, b1=0,b2=0,b3=0;
int encodedIndex = 0;
int dataIndex = 0;
int i = 0;
// if (fDebug ) {
// System.out.println("number of triplets = " + numberTriplets );
// }
for ( i = 0; i<numberTriplets; i++ ) {
dataIndex = i*3;
b1 = binaryData[dataIndex];
b2 = binaryData[dataIndex + 1];
b3 = binaryData[dataIndex + 2];
// if (fDebug) {
// System.out.println( "b1= " + b1 +", b2= " + b2 + ", b3= " + b3 );
// }
l = (byte)(b2 & 0x0f);
k = (byte)(b1 & 0x03);
encodedIndex = i*4;
byte val1 = ((b1 & SIGN)==0)?(byte)(b1>>2):(byte)((b1)>>2^0xc0);
byte val2 = ((b2 & SIGN)==0)?(byte)(b2>>4):(byte)((b2)>>4^0xf0);
byte val3 = ((b3 & SIGN)==0)?(byte)(b3>>6):(byte)((b3)>>6^0xfc);
encodedData[encodedIndex] = lookUpBase64Alphabet[ val1 ];
// if (fDebug) {
// System.out.println( "val2 = " + val2 );
// System.out.println( "k4 = " + (k<<4));
// System.out.println( "vak = " + (val2 | (k<<4)));
// }
encodedData[encodedIndex+1] = lookUpBase64Alphabet[ val2 | ( k<<4 )];
encodedData[encodedIndex+2] = lookUpBase64Alphabet[ (l <<2 ) | val3 ];
encodedData[encodedIndex+3] = lookUpBase64Alphabet[ b3 & 0x3f ];
}
// form integral number of 6-bit groups
dataIndex = i*3;
encodedIndex = i*4;
if (fewerThan24bits == EIGHTBIT ) {
b1 = binaryData[dataIndex];
k = (byte) ( b1 &0x03 );
// if (fDebug ) {
// System.out.println("b1=" + b1);
// System.out.println("b1<<2 = " + (b1>>2) );
// }
byte val1 = ((b1 & SIGN)==0)?(byte)(b1>>2):(byte)((b1)>>2^0xc0);
encodedData[encodedIndex] = lookUpBase64Alphabet[ val1 ];
encodedData[encodedIndex + 1] = lookUpBase64Alphabet[ k<<4 ];
encodedData[encodedIndex + 2] = PAD;
encodedData[encodedIndex + 3] = PAD;
} else if ( fewerThan24bits == SIXTEENBIT ) {
b1 = binaryData[dataIndex];
b2 = binaryData[dataIndex +1 ];
l = ( byte ) ( b2 &0x0f );
k = ( byte ) ( b1 &0x03 );
byte val1 = ((b1 & SIGN)==0)?(byte)(b1>>2):(byte)((b1)>>2^0xc0);
byte val2 = ((b2 & SIGN)==0)?(byte)(b2>>4):(byte)((b2)>>4^0xf0);
encodedData[encodedIndex] = lookUpBase64Alphabet[ val1 ];
encodedData[encodedIndex + 1] = lookUpBase64Alphabet[ val2 | ( k<<4 )];
encodedData[encodedIndex + 2] = lookUpBase64Alphabet[ l<<2 ];
encodedData[encodedIndex + 3] = PAD;
}
return encodedData;
}
/**
* Decodes Base64 data into octects
*
* @param binaryData Byte array containing Base64 data
* @return Array containind decoded data.
*/
public static byte[] decode( byte[] base64Data, IntRef length ) {
int numberQuadruple = base64Data.length/FOURBYTE;
byte decodedData[] = null;
byte b1=0,b2=0,b3=0, b4=0, marker0=0, marker1=0;
// Throw away anything not in base64Data
// Adjust size
int encodedIndex = 0;
int dataIndex = 0;
decodedData = new byte[ numberQuadruple*3 + 1 ];
for (int i = 0; i<numberQuadruple; i++ ) {
dataIndex = i*4;
marker0 = base64Data[dataIndex +2];
marker1 = base64Data[dataIndex +3];
if (base64Data[dataIndex] == PAD)
break;
if (base64Data[dataIndex+1] == PAD)
break;
b1 = base64Alphabet[base64Data[dataIndex]];
b2 = base64Alphabet[base64Data[dataIndex +1]];
if ( marker0 != PAD && marker1 != PAD ) { //No PAD e.g 3cQl
b3 = base64Alphabet[ marker0 ];
b4 = base64Alphabet[ marker1 ];
decodedData[encodedIndex] = (byte)( b1 <<2 | b2>>4 ) ;
decodedData[encodedIndex+1] = (byte)(((b2 & 0xf)<<4 ) |( (b3>>2) & 0xf) );
decodedData[encodedIndex+2] = (byte)( b3<<6 | b4 );
} else if ( marker0 == PAD ) { //Two PAD e.g. 3c[Pad][Pad]
decodedData[encodedIndex] = (byte)( b1 <<2 | b2>>4 ) ;
decodedData[encodedIndex+1] = (byte)((b2 & 0xf)<<4 );
decodedData[encodedIndex+2] = (byte) 0;
encodedIndex += 1;
break;
} else if ( marker1 == PAD ) { //One PAD e.g. 3cQ[Pad]
b3 = base64Alphabet[ marker0 ];
decodedData[encodedIndex] = (byte)( b1 <<2 | b2>>4 );
decodedData[encodedIndex+1] = (byte)(((b2 & 0xf)<<4 ) |( (b3>>2) & 0xf) );
decodedData[encodedIndex+2] = (byte)( b3<<6);
encodedIndex += 2;
break;
}
encodedIndex += 3;
}
length.set(encodedIndex);
return decodedData;
}
}
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