flow like the river

BACK_BACK/node_modules/browserify-aes/modes/cfb1.js

@@ -0,0 +1,42 @@
+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
+}