26 lines
518 B
JavaScript
26 lines
518 B
JavaScript
|
var Buffer = require('safe-buffer').Buffer
|
||
|
|
|
||
|
|
function encryptByte (self, byteParam, decrypt) {
|
||
|
|
var pad = self._cipher.encryptBlock(self._prev)
|
||
|
|
var out = pad[0] ^ byteParam
|
||
|
|
|
||
|
|
self._prev = Buffer.concat([
|
||
|
|
self._prev.slice(1),
|
||
|
|
Buffer.from([decrypt ? byteParam : out])
|
||
|
|
])
|
||
|
|
|
||
|
|
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
|
||
|
|
}
|