From 554fd8c5195424bdbcabf5de30fdc183aba391bd Mon Sep 17 00:00:00 2001 From: upstream source tree Date: Sun, 15 Mar 2015 20:14:05 -0400 Subject: obtained gcc-4.6.4.tar.bz2 from upstream website; verified gcc-4.6.4.tar.bz2.sig; imported gcc-4.6.4 source tree from verified upstream tarball. downloading a git-generated archive based on the 'upstream' tag should provide you with a source tree that is binary identical to the one extracted from the above tarball. if you have obtained the source via the command 'git clone', however, do note that line-endings of files in your working directory might differ from line-endings of the respective files in the upstream repository. --- .../javax/crypto/key/dh/ElGamalKeyAgreement.java | 115 +++++++++++++++++++++ 1 file changed, 115 insertions(+) create mode 100644 libjava/classpath/gnu/javax/crypto/key/dh/ElGamalKeyAgreement.java (limited to 'libjava/classpath/gnu/javax/crypto/key/dh/ElGamalKeyAgreement.java') diff --git a/libjava/classpath/gnu/javax/crypto/key/dh/ElGamalKeyAgreement.java b/libjava/classpath/gnu/javax/crypto/key/dh/ElGamalKeyAgreement.java new file mode 100644 index 000000000..4283dc59b --- /dev/null +++ b/libjava/classpath/gnu/javax/crypto/key/dh/ElGamalKeyAgreement.java @@ -0,0 +1,115 @@ +/* ElGamalKeyAgreement.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.key.dh; + +import gnu.java.security.Registry; +import gnu.java.security.util.Util; + +import gnu.javax.crypto.key.BaseKeyAgreementParty; +import gnu.javax.crypto.key.KeyAgreementException; + +import java.math.BigInteger; + +/** + * The ElGamal key agreement, also known as the half-certified Diffie-Hellman + * key agreement, is described in the Handbook of Applied Cryptography [HAC] as + * follows: + * + *

+ * RFC-2631 describes an Ephemeral-Static Mode of operations with + * Diffie-Hellman keypairs as follows: + * 

+ *  "In Ephemeral-Static mode, the recipient has a static (and certified)
+ *  key pair, but the sender generates a new key pair for each message
+ *  and sends it using the originatorKey production. If the sender's key
+ *  is freshly generated for each message, the shared secret ZZ will be
+ *  similarly different for each message and partyAInfo MAY be omitted,
+ *  since it serves merely to decouple multiple KEKs generated by the
+ *  same set of pairwise keys. If, however, the same ephemeral sender key
+ *  is used for multiple messages (e.g. it is cached as a performance
+ *  optimization) then a separate partyAInfo MUST be used for each
+ *  message. All implementations of this standard MUST implement
+ *  Ephemeral-Static mode."
+ *
+ *

+ * Reference: + *

    + *
  1. Diffie-Hellman Key + * Agreement Method
    + * Eric Rescorla.
    2. + *
  2. [HAC]: Handbook of + * Applied Cryptography.
    + * CRC Press, Inc. ISBN 0-8493-8523-7, 1997
    + * Menezes, A., van Oorschot, P. and S. Vanstone.
    3. + *
+ */ +public abstract class ElGamalKeyAgreement + extends BaseKeyAgreementParty +{ + public static final String SOURCE_OF_RANDOMNESS = "gnu.crypto.elgamal.ka.prng"; + public static final String KA_ELGAMAL_RECIPIENT_PRIVATE_KEY = + "gnu.crypto.elgamal.ka.recipient.private.key"; + public static final String KA_ELGAMAL_RECIPIENT_PUBLIC_KEY = + "gnu.crypto.elgamal.ka.recipient.public.key"; + /** The shared secret key. */ + protected BigInteger ZZ; + + protected ElGamalKeyAgreement() + { + super(Registry.ELGAMAL_KA); + } + + protected byte[] engineSharedSecret() throws KeyAgreementException + { + return Util.trim(ZZ); + } + + protected void engineReset() + { + ZZ = null; + } +} -- cgit v1.2.3