| /* IALG.java -- |
| Copyright (C) 2003, 2006 Free Software Foundation, Inc. |
| |
| This file is a 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 of the License, 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; if not, write to the Free Software |
| Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 |
| USA |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package gnu.javax.crypto.sasl.srp; |
| |
| import gnu.javax.crypto.mac.IMac; |
| import gnu.javax.crypto.mac.MacFactory; |
| |
| import java.security.InvalidKeyException; |
| import java.security.NoSuchAlgorithmException; |
| import java.util.HashMap; |
| |
| import javax.security.sasl.SaslException; |
| |
| /** |
| * A Factory class that returns IALG (Integrity Algorithm) instances that |
| * operate as described in the draft-burdis-cat-sasl-srp-04 and later. |
| */ |
| public final class IALG |
| implements Cloneable |
| { |
| private IMac hmac; |
| |
| /** Private constructor to enforce instantiation through Factory method. */ |
| private IALG(final IMac hmac) |
| { |
| super(); |
| |
| this.hmac = hmac; |
| } |
| |
| /** |
| * Returns an instance of a SASL-SRP IALG implementation. |
| * |
| * @param algorithm the name of the HMAC algorithm. |
| * @return an instance of this object. |
| */ |
| static synchronized IALG getInstance(final String algorithm) |
| throws SaslException |
| { |
| final IMac hmac; |
| hmac = MacFactory.getInstance(algorithm); |
| if (hmac == null) |
| throw new SaslException("getInstance()", |
| new NoSuchAlgorithmException(algorithm)); |
| return new IALG(hmac); |
| } |
| |
| public Object clone() throws CloneNotSupportedException |
| { |
| return new IALG((IMac) hmac.clone()); |
| } |
| |
| public void init(final KDF kdf) throws SaslException |
| { |
| try |
| { |
| final byte[] sk = kdf.derive(hmac.macSize()); |
| final HashMap map = new HashMap(); |
| map.put(IMac.MAC_KEY_MATERIAL, sk); |
| hmac.init(map); |
| } |
| catch (InvalidKeyException x) |
| { |
| throw new SaslException("getInstance()", x); |
| } |
| } |
| |
| public void update(final byte[] data) |
| { |
| hmac.update(data, 0, data.length); |
| } |
| |
| public void update(final byte[] data, final int offset, final int length) |
| { |
| hmac.update(data, offset, length); |
| } |
| |
| public byte[] doFinal() |
| { |
| return hmac.digest(); |
| } |
| |
| /** |
| * Returns the length (in bytes) of this SASL SRP Integrity Algorithm. |
| * |
| * @return the length, in bytes, of this integrity protection algorithm. |
| */ |
| public int length() |
| { |
| return hmac.macSize(); |
| } |
| } |