mirror of
git://gcc.gnu.org/git/gcc.git
synced 2024-12-21 23:59:26 +08:00
109 lines
2.9 KiB
Java
109 lines
2.9 KiB
Java
/* SHA1PRNG.java --- Secure Random SPI SHA1PRNG
|
|
Copyright (C) 1999 Free Software Foundation, Inc.
|
|
|
|
This file is part of GNU Classpath.
|
|
|
|
GNU Classpath is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2, or (at your option)
|
|
any later version.
|
|
|
|
GNU Classpath is distributed in the hope that it will be useful, but
|
|
WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with GNU Classpath; see the file COPYING. If not, write to the
|
|
Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
|
02111-1307 USA.
|
|
|
|
As a special exception, if you link this library with other files to
|
|
produce an executable, this library does not by itself cause the
|
|
resulting executable to be covered by the GNU General Public License.
|
|
This exception does not however invalidate any other reasons why the
|
|
executable file might be covered by the GNU General Public License. */
|
|
|
|
|
|
package gnu.java.security.provider;
|
|
|
|
import java.util.Random;
|
|
import java.security.SecureRandomSpi;
|
|
import java.security.MessageDigest;
|
|
import java.security.NoSuchAlgorithmException;
|
|
import java.io.Serializable;
|
|
|
|
public class SHA1PRNG extends SecureRandomSpi implements Serializable
|
|
{
|
|
MessageDigest digest;
|
|
byte seed[];
|
|
byte data[];
|
|
int seedpos;
|
|
int datapos;
|
|
|
|
public SHA1PRNG()
|
|
{
|
|
try {
|
|
digest = MessageDigest.getInstance("SHA");
|
|
} catch ( NoSuchAlgorithmException nsae) {
|
|
System.out.println("Failed to find SHA Message Digest: " + nsae);
|
|
nsae.printStackTrace();
|
|
}
|
|
|
|
seed = new byte[20];
|
|
seedpos = 0;
|
|
data = new byte[40];
|
|
datapos = 0;
|
|
|
|
new Random().nextBytes(seed);
|
|
|
|
byte digestdata[];
|
|
digestdata = digest.digest( data );
|
|
System.arraycopy( digestdata, 0, data, 0, 20);
|
|
|
|
}
|
|
|
|
public void engineSetSeed(byte[] seed)
|
|
{
|
|
for(int i = 0; i < seed.length; i++)
|
|
this.seed[seedpos++ % 20] ^= seed[i];
|
|
seedpos %= 20;
|
|
|
|
}
|
|
|
|
public void engineNextBytes(byte[] bytes)
|
|
{
|
|
|
|
if( bytes.length < (20 - datapos) ) {
|
|
System.arraycopy( data, datapos, bytes, 0, bytes.length);
|
|
datapos += bytes.length;
|
|
return;
|
|
}
|
|
|
|
int i, blen = bytes.length, bpos = 0;
|
|
byte digestdata[];
|
|
while( bpos < blen ) {
|
|
i = 20 - datapos;
|
|
System.arraycopy( data, datapos, bytes, bpos, i);
|
|
bpos += i;
|
|
datapos += i;
|
|
if( datapos >= 20) {
|
|
//System.out.println( (0 + 20) + "\n" + (20 + 20) );
|
|
System.arraycopy( seed, 0, data, 20, 20);
|
|
digestdata = digest.digest( data );
|
|
System.arraycopy( digestdata, 0, data, 0, 20);
|
|
datapos = 0;
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
public byte[] engineGenerateSeed(int numBytes)
|
|
{
|
|
byte tmp[] = new byte[numBytes];
|
|
|
|
engineNextBytes( tmp );
|
|
return tmp;
|
|
}
|
|
}
|