30 lines
859 B
C++
30 lines
859 B
C++
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#include "InitializationVector.h"
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#include <random>
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#include <sstream>
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using namespace GhettoCipher;
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InitializationVector::InitializationVector(const Block& seed)
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{
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// Since an initialization vector does not have to be a secret,
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// we should be fine just using a mersenne twister seeded with
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// for example the key to fill it up to fit BLOCK_SIZE.
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// Loosely seed mersenne twister with seed
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// Here is nothing copied. Both Block::Get, and Hash<>::operator() take refs.
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std::mt19937 mt = std::mt19937(std::hash<std::bitset<BLOCK_SIZE>>()(seed.Get()));
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// Now generate BLOCK_SIZE urandom bits
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std::stringstream ss;
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for (std::size_t i = 0; i < BLOCK_SIZE; i++)
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ss << (mt() % 2 ? '1' : '0');
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// And create a bitset
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iv = Block(ss.str());
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}
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InitializationVector::operator GhettoCipher::Block() const
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{
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return iv;
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}
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