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47 lines
1.2 KiB
47 lines
1.2 KiB
2 months ago
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using System;
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using Org.BouncyCastle.Math;
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using Org.BouncyCastle.Security;
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using Org.BouncyCastle.Crypto.Parameters;
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namespace Org.BouncyCastle.Crypto.Generators
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{
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public class ElGamalParametersGenerator
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{
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private int size;
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private int certainty;
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private SecureRandom random;
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public void Init(
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int size,
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int certainty,
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SecureRandom random)
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{
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this.size = size;
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this.certainty = certainty;
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this.random = random;
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}
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/**
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* which Generates the p and g values from the given parameters,
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* returning the ElGamalParameters object.
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* <p>
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* Note: can take a while...
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* </p>
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*/
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public ElGamalParameters GenerateParameters()
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{
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//
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// find a safe prime p where p = 2*q + 1, where p and q are prime.
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//
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BigInteger[] safePrimes = DHParametersHelper.GenerateSafePrimes(size, certainty, random);
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BigInteger p = safePrimes[0];
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BigInteger q = safePrimes[1];
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BigInteger g = DHParametersHelper.SelectGenerator(p, q, random);
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return new ElGamalParameters(p, g);
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}
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}
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}
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