1 files changed, 97 insertions, 0 deletions
diff --git a/node_modules/browserify-aes/authCipher.js b/node_modules/browserify-aes/authCipher.js
new file mode 100644
index 000000000..1107a01a5
--- /dev/null
+++ b/node_modules/browserify-aes/authCipher.js
@@ -0,0 +1,97 @@
+var aes = require('./aes')
+var Transform = require('cipher-base')
+var inherits = require('inherits')
+var GHASH = require('./ghash')
+var xor = require('buffer-xor')
+inherits(StreamCipher, Transform)
+module.exports = StreamCipher
+
+function StreamCipher (mode, key, iv, decrypt) {
+  if (!(this instanceof StreamCipher)) {
+    return new StreamCipher(mode, key, iv)
+  }
+  Transform.call(this)
+  this._finID = Buffer.concat([iv, new Buffer([0, 0, 0, 1])])
+  iv = Buffer.concat([iv, new Buffer([0, 0, 0, 2])])
+  this._cipher = new aes.AES(key)
+  this._prev = new Buffer(iv.length)
+  this._cache = new Buffer('')
+  this._secCache = new Buffer('')
+  this._decrypt = decrypt
+  this._alen = 0
+  this._len = 0
+  iv.copy(this._prev)
+  this._mode = mode
+  var h = new Buffer(4)
+  h.fill(0)
+  this._ghash = new GHASH(this._cipher.encryptBlock(h))
+  this._authTag = null
+  this._called = false
+}
+StreamCipher.prototype._update = function (chunk) {
+  if (!this._called && this._alen) {
+    var rump = 16 - (this._alen % 16)
+    if (rump < 16) {
+      rump = new Buffer(rump)
+      rump.fill(0)
+      this._ghash.update(rump)
+    }
+  }
+  this._called = true
+  var out = this._mode.encrypt(this, chunk)
+  if (this._decrypt) {
+    this._ghash.update(chunk)
+  } else {
+    this._ghash.update(out)
+  }
+  this._len += chunk.length
+  return out
+}
+StreamCipher.prototype._final = function () {
+  if (this._decrypt && !this._authTag) {
+    throw new Error('Unsupported state or unable to authenticate data')
+  }
+  var tag = xor(this._ghash.final(this._alen * 8, this._len * 8), this._cipher.encryptBlock(this._finID))
+  if (this._decrypt) {
+    if (xorTest(tag, this._authTag)) {
+      throw new Error('Unsupported state or unable to authenticate data')
+    }
+  } else {
+    this._authTag = tag
+  }
+  this._cipher.scrub()
+}
+StreamCipher.prototype.getAuthTag = function getAuthTag () {
+  if (!this._decrypt && Buffer.isBuffer(this._authTag)) {
+    return this._authTag
+  } else {
+    throw new Error('Attempting to get auth tag in unsupported state')
+  }
+}
+StreamCipher.prototype.setAuthTag = function setAuthTag (tag) {
+  if (this._decrypt) {
+    this._authTag = tag
+  } else {
+    throw new Error('Attempting to set auth tag in unsupported state')
+  }
+}
+StreamCipher.prototype.setAAD = function setAAD (buf) {
+  if (!this._called) {
+    this._ghash.update(buf)
+    this._alen += buf.length
+  } else {
+    throw new Error('Attempting to set AAD in unsupported state')
+  }
+}
+function xorTest (a, b) {
+  var out = 0
+  if (a.length !== b.length) {
+    out++
+  }
+  var len = Math.min(a.length, b.length)
+  var i = -1
+  while (++i < len) {
+    out += (a[i] ^ b[i])
+  }
+  return out
+}