// ========================================================================
// Copyright (c) 1999-2009 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// and Apache License v2.0 which accompanies this distribution.
// The Eclipse Public License is available at
// http://www.eclipse.org/legal/epl-v10.html
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
// You may elect to redistribute this code under either of these licenses.
// ========================================================================
package org.eclipse.jetty.util;
import java.io.ByteArrayOutputStream;
import java.io.UnsupportedEncodingException;
/* ------------------------------------------------------------ */
/** Fast B64 Encoder/Decoder as described in RFC 1421.
* <p>Does not insert or interpret whitespace as described in RFC
* 1521. If you require this you must pre/post process your data.
* <p> Note that in a web context the usual case is to not want
* linebreaks or other white space in the encoded output.
*
*/
public class B64Code
{
// ------------------------------------------------------------------
static final char pad='=';
static final char[] rfc1421alphabet=
{
'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P',
'Q','R','S','T','U','V','W','X','Y','Z','a','b','c','d','e','f',
'g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v',
'w','x','y','z','0','1','2','3','4','5','6','7','8','9','+','/'
};
static final byte[] rfc1421nibbles;
static
{
rfc1421nibbles=new byte[256];
for (int i=0;i<256;i++)
rfc1421nibbles[i]=-1;
for (byte b=0;b<64;b++)
rfc1421nibbles[(byte)rfc1421alphabet[b]]=b;
rfc1421nibbles[(byte)pad]=0;
}
// ------------------------------------------------------------------
/**
* Base 64 encode as described in RFC 1421.
* <p>Does not insert whitespace as described in RFC 1521.
* @param s String to encode.
* @return String containing the encoded form of the input.
*/
static public String encode(String s)
{
try
{
return encode(s,null);
}
catch (UnsupportedEncodingException e)
{
throw new IllegalArgumentException(e.toString());
}
}
// ------------------------------------------------------------------
/**
* Base 64 encode as described in RFC 1421.
* <p>Does not insert whitespace as described in RFC 1521.
* @param s String to encode.
* @param charEncoding String representing the name of
* the character encoding of the provided input String.
* @return String containing the encoded form of the input.
*/
static public String encode(String s,String charEncoding)
throws UnsupportedEncodingException
{
byte[] bytes;
if (charEncoding==null)
bytes=s.getBytes(StringUtil.__ISO_8859_1);
else
bytes=s.getBytes(charEncoding);
return new String(encode(bytes));
}
// ------------------------------------------------------------------
/**
* Fast Base 64 encode as described in RFC 1421.
* <p>Does not insert whitespace as described in RFC 1521.
* <p> Avoids creating extra copies of the input/output.
* @param b byte array to encode.
* @return char array containing the encoded form of the input.
*/
static public char[] encode(byte[] b)
{
return encode(b,false);
}
// ------------------------------------------------------------------
/**
* Fast Base 64 encode as described in RFC 1421 and RFC2045
* <p>Does not insert whitespace as described in RFC 1521, unless rfc2045 is passed as true.
* <p> Avoids creating extra copies of the input/output.
* @param b byte array to encode.
* @param rfc2045 If true, break lines at 76 characters with CRLF
* @return char array containing the encoded form of the input.
*/
static public char[] encode(byte[] b, boolean rfc2045)
{
if (b==null)
return null;
int bLen=b.length;
int cLen=((bLen+2)/3)*4;
if (rfc2045)
cLen+=2+2*cLen/76;
char c[]=new char[cLen];
int ci=0;
int bi=0;
byte b0, b1, b2;
int stop=(bLen/3)*3;
int l=0;
while (bi<stop)
{
b0=b[bi++];
b1=b[bi++];
b2=b[bi++];
c[ci++]=rfc1421alphabet[(b0>>>2)&0x3f];
c[ci++]=rfc1421alphabet[(b0<<4)&0x3f|(b1>>>4)&0x0f];
c[ci++]=rfc1421alphabet[(b1<<2)&0x3f|(b2>>>6)&0x03];
c[ci++]=rfc1421alphabet[b2&077];
l+=4;
if (rfc2045 && l%76==0)
{
c[ci++]=13;
c[ci++]=10;
}
}
if (bLen!=bi)
{
switch (bLen%3)
{
case 2:
b0=b[bi++];
b1=b[bi++];
c[ci++]=rfc1421alphabet[(b0>>>2)&0x3f];
c[ci++]=rfc1421alphabet[(b0<<4)&0x3f|(b1>>>4)&0x0f];
c[ci++]=rfc1421alphabet[(b1<<2)&0x3f];
c[ci++]=pad;
break;
case 1:
b0=b[bi++];
c[ci++]=rfc1421alphabet[(b0>>>2)&0x3f];
c[ci++]=rfc1421alphabet[(b0<<4)&0x3f];
c[ci++]=pad;
c[ci++]=pad;
break;
default:
break;
}
}
if (rfc2045)
{
c[ci++]=13;
c[ci++]=10;
}
return c;
}
// ------------------------------------------------------------------
/**
* Base 64 decode as described in RFC 2045.
* <p>Unlike {@link #decode(char[])}, extra whitespace is ignored.
* @param encoded String to decode.
* @param charEncoding String representing the character encoding
* used to map the decoded bytes into a String.
* @return String decoded byte array.
* @throws UnsupportedEncodingException if the encoding is not supported
* @throws IllegalArgumentException if the input is not a valid
* B64 encoding.
*/
static public String decode(String encoded,String charEncoding)
throws UnsupportedEncodingException
{
byte[] decoded=decode(encoded);
if (charEncoding==null)
return new String(decoded);
return new String(decoded,charEncoding);
}
/* ------------------------------------------------------------ */
/**
* Fast Base 64 decode as described in RFC 1421.
*
* <p>Unlike other decode methods, this does not attempt to
* cope with extra whitespace as described in RFC 1521/2045.
* <p> Avoids creating extra copies of the input/output.
* <p> Note this code has been flattened for performance.
* @param b char array to decode.
* @return byte array containing the decoded form of the input.
* @throws IllegalArgumentException if the input is not a valid
* B64 encoding.
*/
static public byte[] decode(char[] b)
{
if (b==null)
return null;
int bLen=b.length;
if (bLen%4!=0)
throw new IllegalArgumentException("Input block size is not 4");
int li=bLen-1;
while (li>=0 && b[li]==(byte)pad)
li--;
if (li<0)
return new byte[0];
// Create result array of exact required size.
int rLen=((li+1)*3)/4;
byte r[]=new byte[rLen];
int ri=0;
int bi=0;
int stop=(rLen/3)*3;
byte b0,b1,b2,b3;
try
{
while (ri<stop)
{
b0=rfc1421nibbles[b[bi++]];
b1=rfc1421nibbles[b[bi++]];
b2=rfc1421nibbles[b[bi++]];
b3=rfc1421nibbles[b[bi++]];
if (b0<0 || b1<0 || b2<0 || b3<0)
throw new IllegalArgumentException("Not B64 encoded");
r[ri++]=(byte)(b0<<2|b1>>>4);
r[ri++]=(byte)(b1<<4|b2>>>2);
r[ri++]=(byte)(b2<<6|b3);
}
if (rLen!=ri)
{
switch (rLen%3)
{
case 2:
b0=rfc1421nibbles[b[bi++]];
b1=rfc1421nibbles[b[bi++]];
b2=rfc1421nibbles[b[bi++]];
if (b0<0 || b1<0 || b2<0)
throw new IllegalArgumentException("Not B64 encoded");
r[ri++]=(byte)(b0<<2|b1>>>4);
r[ri++]=(byte)(b1<<4|b2>>>2);
break;
case 1:
b0=rfc1421nibbles[b[bi++]];
b1=rfc1421nibbles[b[bi++]];
if (b0<0 || b1<0)
throw new IllegalArgumentException("Not B64 encoded");
r[ri++]=(byte)(b0<<2|b1>>>4);
break;
default:
break;
}
}
}
catch (IndexOutOfBoundsException e)
{
throw new IllegalArgumentException("char "+bi
+" was not B64 encoded");
}
return r;
}
/* ------------------------------------------------------------ */
/**
* Base 64 decode as described in RFC 2045.
* <p>Unlike {@link #decode(char[])}, extra whitespace is ignored.
* @param encoded String to decode.
* @return byte array containing the decoded form of the input.
* @throws IllegalArgumentException if the input is not a valid
* B64 encoding.
*/
static public byte[] decode(String encoded)
{
if (encoded==null)
return null;
int ci=0;
byte nibbles[] = new byte[4];
int s=0;
ByteArrayOutputStream bout = new ByteArrayOutputStream(4*encoded.length()/3);
while (ci<encoded.length())
{
char c=encoded.charAt(ci++);
if (c==pad)
break;
if (Character.isWhitespace(c))
continue;
byte nibble=rfc1421nibbles[c];
if (nibble<0)
throw new IllegalArgumentException("Not B64 encoded");
nibbles[s++]=rfc1421nibbles[c];
switch(s)
{
case 1:
break;
case 2:
bout.write(nibbles[0]<<2|nibbles[1]>>>4);
break;
case 3:
bout.write(nibbles[1]<<4|nibbles[2]>>>2);
break;
case 4:
bout.write(nibbles[2]<<6|nibbles[3]);
s=0;
break;
}
}
return bout.toByteArray();
}
}