Files
0xb00b5-packmate/src/main/java/ru/serega6531/packmate/utils/HMAC.java
2020-04-22 19:27:38 +03:00

104 lines
3.0 KiB
Java

/*
* Copyright 2001-2011 Joel Hockey (joel.hockey@gmail.com). All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package ru.serega6531.packmate.utils;
import java.security.MessageDigest;
/**
* https://github.com/joelhockey/tls/blob/master/src/main/java/net/java/jless/tls/HMAC.java
*/
public class HMAC {
private byte[] k_ipad = new byte[64];
private byte[] k_opad = new byte[64];
MessageDigest md = null;
/**
* Class constructor specifying the MessageDigest and secret to use
*
* @param md the MessageDigest (MD5 or SHA1).
* @param key the secret to seed the md.
*/
public HMAC(MessageDigest md, byte[] key) {
setMD(md);
setKey(key);
}
/**
* Set the MessageDigest for HMAC
*
* @param md the MessageDigest
*/
public void setMD(MessageDigest md) {
this.md = md;
}
/**
* Set the secret key for HMAC
*
* @param key the key.
*/
public void setKey(byte[] key) {
int keyLength = 0;
// get keyLength.
if (key == null) {
keyLength = 0;
} else {
keyLength = key.length;
}
// if the key is longer than 64 bytes then hash it.
byte[] tempKey = keyLength > 64 ? md.digest(key) : key;
// get m_k_ipad and m_k_opad
for (int i = 0; i < keyLength; i++) {
k_ipad[i] = (byte) (0x36 ^ tempKey[i]);
k_opad[i] = (byte) (0x5C ^ tempKey[i]);
}
for (int i = keyLength; i < 64; i++) {
k_ipad[i] = 0x36;
k_opad[i] = 0x5C;
}
}
/**
* Digest the HMAC
*
* @param input the byte array input
* @return HMAC value
*/
public byte[] digest(byte[] input) {
md.reset();
md.update(k_ipad);
md.update(input);
byte[] inner = md.digest();
md.update(k_opad);
md.update(inner);
return md.digest();
}
}