1 files changed, 31 insertions, 0 deletions
diff --git a/node_modules/browserify-aes/modes/ctr.js b/node_modules/browserify-aes/modes/ctr.js
new file mode 100644
index 000000000..0ef2278bf
--- /dev/null
+++ b/node_modules/browserify-aes/modes/ctr.js
@@ -0,0 +1,31 @@
+var xor = require('buffer-xor')
+
+function incr32 (iv) {
+  var len = iv.length
+  var item
+  while (len--) {
+    item = iv.readUInt8(len)
+    if (item === 255) {
+      iv.writeUInt8(0, len)
+    } else {
+      item++
+      iv.writeUInt8(item, len)
+      break
+    }
+  }
+}
+
+function getBlock (self) {
+  var out = self._cipher.encryptBlock(self._prev)
+  incr32(self._prev)
+  return out
+}
+
+exports.encrypt = function (self, chunk) {
+  while (self._cache.length < chunk.length) {
+    self._cache = Buffer.concat([self._cache, getBlock(self)])
+  }
+  var pad = self._cache.slice(0, chunk.length)
+  self._cache = self._cache.slice(chunk.length)
+  return xor(chunk, pad)
+}