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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
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*
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package com.sun.crypto.provider;
import java.nio.ByteBuffer;
import javax.crypto.MacSpi;
import javax.crypto.SecretKey;
import java.security.*;
import java.security.spec.AlgorithmParameterSpec;
import static com.sun.crypto.provider.TlsPrfGenerator.genPad;
/**
* This file contains the code for the SslMacMD5 and SslMacSHA1 implementations.
* The SSL 3.0 MAC is a variation of the HMAC algorithm.
*
* Note that we don't implement Cloneable as that is not needed for SSL.
*
* @author Andreas Sterbenz
* @since 1.6
*/
final class SslMacCore {
private final MessageDigest md;
private final byte[] pad1, pad2;
private boolean first; // Is this the first data to be processed?
private byte[] secret;
/**
* Standard constructor, creates a new SslMacCore instance instantiating
* a MessageDigest of the specified name.
*/
SslMacCore(String digestAlgorithm, byte[] pad1, byte[] pad2)
throws NoSuchAlgorithmException {
md = MessageDigest.getInstance(digestAlgorithm);
this.pad1 = pad1;
this.pad2 = pad2;
first = true;
}
/**
* Returns the length of the Mac in bytes.
*
* @return the Mac length in bytes.
*/
int getDigestLength() {
return md.getDigestLength();
}
/**
* Initializes the Mac with the given secret key and algorithm parameters.
*
* @param key the secret key.
* @param params the algorithm parameters.
*
* @exception InvalidKeyException if the given key is inappropriate for
* initializing this MAC.
* @exception InvalidAlgorithmParameterException if the given algorithm
* parameters are inappropriate for this MAC.
*/
void init(Key key, AlgorithmParameterSpec params)
throws InvalidKeyException, InvalidAlgorithmParameterException {
if (params != null) {
throw new InvalidAlgorithmParameterException
("SslMac does not use parameters");
}
if (!(key instanceof SecretKey)) {
throw new InvalidKeyException("Secret key expected");
}
secret = key.getEncoded();
if (secret == null || secret.length == 0) {
throw new InvalidKeyException("Missing key data");
}
reset();
}
/**
* Processes the given byte.
*
* @param input the input byte to be processed.
*/
void update(byte input) {
if (first == true) {
// compute digest for 1st pass; start with inner pad
md.update(secret);
md.update(pad1);
first = false;
}
// add the passed byte to the inner digest
md.update(input);
}
/**
* Processes the first <code>len</code> bytes in <code>input</code>,
* starting at <code>offset</code>.
*
* @param input the input buffer.
* @param offset the offset in <code>input</code> where the input starts.
* @param len the number of bytes to process.
*/
void update(byte input[], int offset, int len) {
if (first == true) {
// compute digest for 1st pass; start with inner pad
md.update(secret);
md.update(pad1);
first = false;
}
// add the selected part of an array of bytes to the inner digest
md.update(input, offset, len);
}
void update(ByteBuffer input) {
if (first == true) {
// compute digest for 1st pass; start with inner pad
md.update(secret);
md.update(pad1);
first = false;
}
md.update(input);
}
/**
* Completes the Mac computation and resets the Mac for further use,
* maintaining the secret key that the Mac was initialized with.
*
* @return the Mac result.
*/
byte[] doFinal() {
if (first == true) {
// compute digest for 1st pass; start with inner pad
md.update(secret);
md.update(pad1);
} else {
first = true;
}
try {
// finish the inner digest
byte[] tmp = md.digest();
// compute digest for 2nd pass; start with outer pad
md.update(secret);
md.update(pad2);
// add result of 1st hash
md.update(tmp);
md.digest(tmp, 0, tmp.length);
return tmp;
} catch (DigestException e) {
// should never occur
throw new ProviderException(e);
}
}
/**
* Resets the Mac for further use, maintaining the secret key that the
* Mac was initialized with.
*/
void reset() {
if (first == false) {
md.reset();
first = true;
}
}
// nested static class for the SslMacMD5 implementation
public static final class SslMacMD5 extends MacSpi {
private final SslMacCore core;
public SslMacMD5() throws NoSuchAlgorithmException {
core = new SslMacCore("MD5", md5Pad1, md5Pad2);
}
protected int engineGetMacLength() {
return core.getDigestLength();
}
protected void engineInit(Key key, AlgorithmParameterSpec params)
throws InvalidKeyException, InvalidAlgorithmParameterException {
core.init(key, params);
}
protected void engineUpdate(byte input) {
core.update(input);
}
protected void engineUpdate(byte input[], int offset, int len) {
core.update(input, offset, len);
}
protected void engineUpdate(ByteBuffer input) {
core.update(input);
}
protected byte[] engineDoFinal() {
return core.doFinal();
}
protected void engineReset() {
core.reset();
}
static final byte[] md5Pad1 = genPad((byte)0x36, 48);
static final byte[] md5Pad2 = genPad((byte)0x5c, 48);
static {
SunJCE.ensureIntegrity(SslMacMD5.class);
}
}
// nested static class for the SslMacMD5 implementation
public static final class SslMacSHA1 extends MacSpi {
private final SslMacCore core;
public SslMacSHA1() throws NoSuchAlgorithmException {
core = new SslMacCore("SHA", shaPad1, shaPad2);
}
protected int engineGetMacLength() {
return core.getDigestLength();
}
protected void engineInit(Key key, AlgorithmParameterSpec params)
throws InvalidKeyException, InvalidAlgorithmParameterException {
core.init(key, params);
}
protected void engineUpdate(byte input) {
core.update(input);
}
protected void engineUpdate(byte input[], int offset, int len) {
core.update(input, offset, len);
}
protected void engineUpdate(ByteBuffer input) {
core.update(input);
}
protected byte[] engineDoFinal() {
return core.doFinal();
}
protected void engineReset() {
core.reset();
}
static final byte[] shaPad1 = genPad((byte)0x36, 40);
static final byte[] shaPad2 = genPad((byte)0x5c, 40);
static {
SunJCE.ensureIntegrity(SslMacSHA1.class);
}
}
}