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-rw-r--r--node_modules/browserify-aes/modes/ctr.js30
1 files changed, 30 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 0000000..e68f13c
--- /dev/null
+++ b/node_modules/browserify-aes/modes/ctr.js
@@ -0,0 +1,30 @@
+var xor = require('buffer-xor')
+var Buffer = require('safe-buffer').Buffer
+var incr32 = require('../incr32')
+
+function getBlock (self) {
+ var out = self._cipher.encryptBlockRaw(self._prev)
+ incr32(self._prev)
+ return out
+}
+
+var blockSize = 16
+exports.encrypt = function (self, chunk) {
+ var chunkNum = Math.ceil(chunk.length / blockSize)
+ var start = self._cache.length
+ self._cache = Buffer.concat([
+ self._cache,
+ Buffer.allocUnsafe(chunkNum * blockSize)
+ ])
+ for (var i = 0; i < chunkNum; i++) {
+ var out = getBlock(self)
+ var offset = start + i * blockSize
+ self._cache.writeUInt32BE(out[0], offset + 0)
+ self._cache.writeUInt32BE(out[1], offset + 4)
+ self._cache.writeUInt32BE(out[2], offset + 8)
+ self._cache.writeUInt32BE(out[3], offset + 12)
+ }
+ var pad = self._cache.slice(0, chunk.length)
+ self._cache = self._cache.slice(chunk.length)
+ return xor(chunk, pad)
+}