31 lines
597 B
JavaScript
31 lines
597 B
JavaScript
/**
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* Zero padding strategy.
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*/
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export const ZeroPadding = {
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pad(data, blockSize) {
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const _data = data;
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// Shortcut
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const blockSizeBytes = blockSize * 4;
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// Pad
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_data.clamp();
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_data.sigBytes += blockSizeBytes - ((data.sigBytes % blockSizeBytes) || blockSizeBytes);
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},
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unpad(data) {
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const _data = data;
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// Shortcut
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const dataWords = _data.words;
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// Unpad
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for (let i = _data.sigBytes - 1; i >= 0; i -= 1) {
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if (((dataWords[i >>> 2] >>> (24 - (i % 4) * 8)) & 0xff)) {
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_data.sigBytes = i + 1;
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break;
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}
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}
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},
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};
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