| /base/000_base/bower_components/cryptojslib/components/mode-cfb.js |
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| @@ -0,0 +1,64 @@ |
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| /* |
| CryptoJS v3.1.2 |
| code.google.com/p/crypto-js |
| (c) 2009-2013 by Jeff Mott. All rights reserved. |
| code.google.com/p/crypto-js/wiki/License |
| */ |
| /** |
| * Cipher Feedback block mode. |
| */ |
| CryptoJS.mode.CFB = (function () { |
| var CFB = CryptoJS.lib.BlockCipherMode.extend(); |
| |
| CFB.Encryptor = CFB.extend({ |
| processBlock: function (words, offset) { |
| // Shortcuts |
| var cipher = this._cipher; |
| var blockSize = cipher.blockSize; |
| |
| generateKeystreamAndEncrypt.call(this, words, offset, blockSize, cipher); |
| |
| // Remember this block to use with next block |
| this._prevBlock = words.slice(offset, offset + blockSize); |
| } |
| }); |
| |
| CFB.Decryptor = CFB.extend({ |
| processBlock: function (words, offset) { |
| // Shortcuts |
| var cipher = this._cipher; |
| var blockSize = cipher.blockSize; |
| |
| // Remember this block to use with next block |
| var thisBlock = words.slice(offset, offset + blockSize); |
| |
| generateKeystreamAndEncrypt.call(this, words, offset, blockSize, cipher); |
| |
| // This block becomes the previous block |
| this._prevBlock = thisBlock; |
| } |
| }); |
| |
| function generateKeystreamAndEncrypt(words, offset, blockSize, cipher) { |
| // Shortcut |
| var iv = this._iv; |
| |
| // Generate keystream |
| if (iv) { |
| var keystream = iv.slice(0); |
| |
| // Remove IV for subsequent blocks |
| this._iv = undefined; |
| } else { |
| var keystream = this._prevBlock; |
| } |
| cipher.encryptBlock(keystream, 0); |
| |
| // Encrypt |
| for (var i = 0; i < blockSize; i++) { |
| words[offset + i] ^= keystream[i]; |
| } |
| } |
| |
| return CFB; |
| }()); |
