30 lines
989 B
C#
30 lines
989 B
C#
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namespace Obfuz.EncryptionVM.Instructions
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{
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public class BitRotateInstruction : EncryptionInstructionBase
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{
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private readonly int _rotateBitNum;
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private readonly int _opKeyIndex;
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public BitRotateInstruction(int rotateBitNum, int opKeyIndex)
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{
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_rotateBitNum = rotateBitNum;
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_opKeyIndex = opKeyIndex;
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}
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public override int Encrypt(int value, int[] secretKey, int salt)
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{
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uint part1 = (uint)value << _rotateBitNum;
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uint part2 = (uint)value >> (32 - _rotateBitNum);
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return ((int)(part1 | part2) ^ secretKey[_opKeyIndex]) + salt;
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}
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public override int Decrypt(int value, int[] secretKey, int salt)
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{
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uint value2 = (uint)((value - salt) ^ secretKey[_opKeyIndex]);
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uint part1 = value2 >> _rotateBitNum;
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uint part2 = value2 << (32 - _rotateBitNum);
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return (int)(part1 | part2);
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}
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}
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}
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