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src/share/classes/com/sun/crypto/provider/DHParameterGenerator.java

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rev 12543 : 8181048: Refactor existing providers to refer to the same constants for default values for key length
Reviewed-by: mullan, ahgross
   1 /*
   2  * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package com.sun.crypto.provider;
  27 
  28 import java.security.*;
  29 import java.security.spec.*;
  30 import javax.crypto.spec.DHParameterSpec;
  31 import javax.crypto.spec.DHGenParameterSpec;
  32 


  33 /*
  34  * This class generates parameters for the Diffie-Hellman algorithm.
  35  * The parameters are a prime, a base, and optionally the length in bits of
  36  * the private value.
  37  *
  38  * <p>The Diffie-Hellman parameter generation accepts the size in bits of the
  39  * prime modulus and the size in bits of the random exponent as input.
  40  * The size of the prime modulus defaults to 1024 bits.
  41  *
  42  * @author Jan Luehe
  43  *
  44  *
  45  * @see java.security.AlgorithmParameters
  46  * @see java.security.spec.AlgorithmParameterSpec
  47  * @see DHParameters
  48  */
  49 public final class DHParameterGenerator
  50 extends AlgorithmParameterGeneratorSpi {
  51 
  52     // The size in bits of the prime modulus
  53     private int primeSize = 1024;
  54 
  55     // The size in bits of the random exponent (private value)
  56     private int exponentSize = 0;
  57 
  58     // The source of randomness
  59     private SecureRandom random = null;
  60 
  61     private static void checkKeySize(int keysize)
  62             throws InvalidParameterException {
  63             if ((keysize != 2048) &&
  64             ((keysize < 512) || (keysize > 1024) || (keysize % 64 != 0))) {
  65             throw new InvalidParameterException(
  66                     "DH key size must be multiple of 64 and range " +
  67                     "from 512 to 1024 (inclusive), or 2048. " +
  68                     "The specific key size " + keysize + " is not supported");
  69         }
  70     }
  71 
  72     /**
  73      * Initializes this parameter generator for a certain keysize


   1 /*
   2  * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package com.sun.crypto.provider;
  27 
  28 import java.security.*;
  29 import java.security.spec.*;
  30 import javax.crypto.spec.DHParameterSpec;
  31 import javax.crypto.spec.DHGenParameterSpec;
  32 
  33 import static sun.security.util.SecurityProviderConstants.DEF_DH_KEY_SIZE;
  34 
  35 /*
  36  * This class generates parameters for the Diffie-Hellman algorithm.
  37  * The parameters are a prime, a base, and optionally the length in bits of
  38  * the private value.
  39  *
  40  * <p>The Diffie-Hellman parameter generation accepts the size in bits of the
  41  * prime modulus and the size in bits of the random exponent as input.

  42  *
  43  * @author Jan Luehe
  44  *
  45  *
  46  * @see java.security.AlgorithmParameters
  47  * @see java.security.spec.AlgorithmParameterSpec
  48  * @see DHParameters
  49  */
  50 public final class DHParameterGenerator
  51 extends AlgorithmParameterGeneratorSpi {
  52 
  53     // The size in bits of the prime modulus
  54     private int primeSize = DEF_DH_KEY_SIZE;
  55 
  56     // The size in bits of the random exponent (private value)
  57     private int exponentSize = 0;
  58 
  59     // The source of randomness
  60     private SecureRandom random = null;
  61 
  62     private static void checkKeySize(int keysize)
  63             throws InvalidParameterException {
  64             if ((keysize != 2048) &&
  65             ((keysize < 512) || (keysize > 1024) || (keysize % 64 != 0))) {
  66             throw new InvalidParameterException(
  67                     "DH key size must be multiple of 64 and range " +
  68                     "from 512 to 1024 (inclusive), or 2048. " +
  69                     "The specific key size " + keysize + " is not supported");
  70         }
  71     }
  72 
  73     /**
  74      * Initializes this parameter generator for a certain keysize


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