2022-03-17 11:33:23 +00:00
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package ch.fhnw.kry;
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public class SPN {
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2022-03-17 11:46:28 +00:00
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private final static int ROUND_KEY_LENGTH = 16;
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2022-03-17 11:33:23 +00:00
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public int k(int key, int i) {
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i *= 4;
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2022-03-17 11:46:28 +00:00
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int mask = 0xFFFF_0000 >>> i;
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2022-03-17 11:33:23 +00:00
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2022-03-17 11:46:28 +00:00
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return key & mask >>> ROUND_KEY_LENGTH - i;
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2022-03-17 11:33:23 +00:00
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}
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}
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