| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| package org.apache.wss4j.common.derivedKey; |
| |
| /** |
| * |
| <pre> |
| P_SHA-1 DEFINITION |
| ================== |
| <b>P_SHA-1(secret, seed)</b> = |
| HMAC_SHA-1(secret, A(1) + seed) + |
| HMAC_SHA-1(secret, A(2) + seed) + |
| HMAC_SHA-1(secret, A(3) + seed) + ... |
| <i>Where + indicates concatenation.</i> |
| <br> |
| A() is defined as: |
| A(0) = seed |
| A(i) = HMAC_SHA-1(secret, A(i-1)) |
| <br> |
| <i>Source : RFC 2246 - The TLS Protocol Version 1.0 |
| Section 5. HMAC and the pseudorandom function</i> |
| </pre> |
| */ |
| |
| import javax.crypto.Mac; |
| import javax.crypto.spec.SecretKeySpec; |
| |
| import org.apache.wss4j.common.ext.WSSecurityException; |
| |
| import java.security.InvalidKeyException; |
| import java.security.NoSuchAlgorithmException; |
| |
| public class P_SHA1 implements DerivationAlgorithm { |
| |
| @Override |
| public byte[] createKey(byte[] secret, byte[] seed, int offset, long length) |
| throws WSSecurityException { |
| |
| try { |
| Mac mac = Mac.getInstance("HmacSHA1"); |
| |
| byte[] tempBytes = pHash(secret, seed, mac, offset + (int) length); |
| |
| byte[] key = new byte[(int) length]; |
| |
| System.arraycopy(tempBytes, offset, key, 0, key.length); |
| |
| return key; |
| } catch (NoSuchAlgorithmException | InvalidKeyException e) { |
| throw new WSSecurityException(WSSecurityException.ErrorCode.FAILURE, e, "errorInKeyDerivation"); |
| } |
| } |
| |
| /** |
| * P_hash as defined in RFC 2246 for TLS. |
| * |
| * @param secret is the key for the HMAC |
| * @param seed the seed value to start the generation - A(0) |
| * @param mac the HMAC algorithm |
| * @param required number of bytes to generate |
| * @return a byte array that contains a secret key |
| * @throws InvalidKeyException |
| */ |
| private static byte[] pHash(byte[] secret, byte[] seed, Mac mac, int required) |
| throws InvalidKeyException { |
| |
| byte[] out = new byte[required]; |
| int offset = 0, tocpy; |
| byte[] a = seed; // a(0) is the seed |
| byte[] tmp; |
| |
| SecretKeySpec key = new SecretKeySpec(secret, "HMACSHA1"); |
| mac.init(key); |
| |
| int bytesRequired = required; |
| while (bytesRequired > 0) { |
| mac.update(a); |
| a = mac.doFinal(); |
| mac.update(a); |
| mac.update(seed); |
| tmp = mac.doFinal(); |
| tocpy = Math.min(bytesRequired, tmp.length); |
| System.arraycopy(tmp, 0, out, offset, tocpy); |
| offset += tocpy; |
| bytesRequired -= tocpy; |
| } |
| return out; |
| } |
| } |