34 lines
869 B
JavaScript
34 lines
869 B
JavaScript
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var Buffer = require('safe-buffer').Buffer
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var xor = require('buffer-xor')
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function encryptStart (self, data, decrypt) {
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var len = data.length
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var out = xor(data, self._cache)
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self._cache = self._cache.slice(len)
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self._prev = Buffer.concat([self._prev, decrypt ? data : out])
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return out
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}
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exports.encrypt = function (self, data, decrypt) {
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var out = Buffer.allocUnsafe(0)
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var len
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while (data.length) {
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if (self._cache.length === 0) {
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self._cache = self._cipher.encryptBlock(self._prev)
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self._prev = Buffer.allocUnsafe(0)
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}
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if (self._cache.length <= data.length) {
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len = self._cache.length
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out = Buffer.concat([out, encryptStart(self, data.slice(0, len), decrypt)])
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data = data.slice(len)
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} else {
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out = Buffer.concat([out, encryptStart(self, data, decrypt)])
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break
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}
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}
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return out
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}
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