aaac7fed
 liuqimichale
add
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var Buffer = require('safe-buffer').Buffer
function encryptByte (self, byteParam, decrypt) {
var pad
var i = -1
var len = 8
var out = 0
var bit, value
while (++i < len) {
pad = self._cipher.encryptBlock(self._prev)
bit = (byteParam & (1 << (7 - i))) ? 0x80 : 0
value = pad[0] ^ bit
out += ((value & 0x80) >> (i % 8))
self._prev = shiftIn(self._prev, decrypt ? bit : value)
}
return out
}
function shiftIn (buffer, value) {
var len = buffer.length
var i = -1
var out = Buffer.allocUnsafe(buffer.length)
buffer = Buffer.concat([buffer, Buffer.from([value])])
while (++i < len) {
out[i] = buffer[i] << 1 | buffer[i + 1] >> (7)
}
return out
}
exports.encrypt = function (self, chunk, decrypt) {
var len = chunk.length
var out = Buffer.allocUnsafe(len)
var i = -1
while (++i < len) {
out[i] = encryptByte(self, chunk[i], decrypt)
}
return out
}
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