26 lines
518 B
JavaScript
26 lines
518 B
JavaScript
var Buffer = require('safe-buffer').Buffer
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function encryptByte (self, byteParam, decrypt) {
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var pad = self._cipher.encryptBlock(self._prev)
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var out = pad[0] ^ byteParam
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self._prev = Buffer.concat([
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self._prev.slice(1),
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Buffer.from([decrypt ? byteParam : out])
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])
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return out
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}
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exports.encrypt = function (self, chunk, decrypt) {
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var len = chunk.length
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var out = Buffer.allocUnsafe(len)
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var i = -1
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while (++i < len) {
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out[i] = encryptByte(self, chunk[i], decrypt)
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}
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return out
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}
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