/*
* @(#)basic.java 1.10 95/08/29 Jonathan Payne
*
* Copyright (c) 1994 Sun Microsystems, Inc. All Rights Reserved.
*
* Permission to use, copy, modify, and distribute this software
* and its documentation for NON-COMMERCIAL purposes and without
* fee is hereby granted provided that this copyright notice
* appears in all copies. Please refer to the file "copyright.html"
* for further important copyright and licensing information.
*
* SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF
* THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
* TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR
* ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
* DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.
*/
package sun.net.www.auth;
import java.io.*;
/**
* From RFC 1421
*
* @version 1.10 29 Aug 1995
* @author Jonathan Payne
*
* This class has a lowercase name because we usually create an
* instance of it by catenating the name of the current
* authentication type with the package name. In order to guarantee
* a consistent pattern we always convert the authentication type to
* lower case.
*/
public class basic extends Authenticator {
static private byte six2print[] = {
'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 private byte print2six[] = new byte[128];
static final int ILLEGAL = -1;
static {
int i, limit;
limit = six2print.length;
for (i = print2six.length; --i >= 0; ) {
print2six[i] = (byte) ILLEGAL;
}
for (i = 0; --limit >= 0; i++) {
print2six[six2print[i]] = (byte) i;
}
}
public void encrypt(InputStream is, OutputStream os) throws IOException {
int chunk;
int c = -1;
int lineCnt = 64;
int shift;
loop:
do {
shift = 24;
chunk = 0;
while ((shift -= 8) >= 0) {
switch (c = is.read()) {
case -1:
break loop;
default:
chunk |= (c << shift);
break;
}
}
shift = 24;
while ((shift -= 6) >= 0) {
os.write(six2print[(chunk >> shift) & 0x3f]);
}
if ((lineCnt -= 4) == 0) {
os.write('\n');
lineCnt = 64;
}
} while (true);
switch (shift) {
case 16: /* 0 bits left to process */
break;
case 8: /* 8 bits (1 byte) left to process */
os.write(six2print[(chunk >> 18) & 0x3f]);
os.write(six2print[(chunk >> 12) & 0x3f]);
os.write('=');
os.write('=');
break;
case 0: /* 16 bits (2 bytes) left to process */
os.write(six2print[(chunk >> 18) & 0x3f]);
os.write(six2print[(chunk >> 12) & 0x3f]);
os.write(six2print[(chunk >> 6) & 0x3f]);
os.write('=');
break;
}
}
public void decrypt(InputStream is, OutputStream os) throws IOException {
int c;
int shift;
int chunk;
int charCnt = 64;
loop:
do {
shift = 24;
chunk = 0;
while ((shift -= 6) >= 0) {
switch (c = is.read()) {
case '=':
break loop;
case '\n':
if (charCnt == 0) {
charCnt = 64;
continue loop;
}
throw new IOException("Invalid encryption");
case -1:
if (shift == 18) {
throw new IOException("Invalid encryption");
}
break loop;
default:
{
int cc = print2six[c];
switch (cc) {
case ILLEGAL:
throw new IOException("Invalid encryption");
default:
chunk |= (cc << shift);
break;
}
}
break;
}
}
shift = 24;
while ((shift -= 8) >= 0) {
os.write((chunk >> shift) & 0xff);
}
charCnt -= 4;
} while (true);
switch (shift) {
case 18: /* nothing to process */
break;
case 12: /* one 6 bit entity is illegal */
throw new IOException("Invalid encryption");
case 6: /* two 6 bit entities = one 8 bit byte */
os.write((chunk >> 16) & 0xff);
break;
case 0:
os.write((chunk >> 16) & 0xff);
os.write(chunk & 0xff);
break;
}
}
static public void main(String args[]) throws IOException {
Authenticator a = new basic();
FileOutputStream os = new FileOutputStream("/home/jpayne/livejava/test.uu");
a.encrypt(new FileInputStream("/home/jpayne/livejava/test.ascii"), os);
os.close();
a.decrypt(new FileInputStream("/home/jpayne/livejava/test.uu"), System.out);
System.out.flush();
}
}