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2025-07-17 2cfe454c309a65f02e89063d8306ff71f86b7f5c

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;(function (root, factory, undef) {
    if (typeof exports === "object") {
        // CommonJS
        module.exports = exports = factory(require("./core"), require("./cipher-core"));
    }
    else if (typeof define === "function" && define.amd) {
        // AMD
        define(["./core", "./cipher-core"], factory);
    }
    else {
        // Global (browser)
        factory(root.CryptoJS);
    }
}(this, function (CryptoJS) {
 
    /**
     * 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) {
            var keystream;
 
            // Shortcut
            var iv = this._iv;
 
            // Generate keystream
            if (iv) {
                keystream = iv.slice(0);
 
                // Remove IV for subsequent blocks
                this._iv = undefined;
            } else {
                keystream = this._prevBlock;
            }
            cipher.encryptBlock(keystream, 0);
 
            // Encrypt
            for (var i = 0; i < blockSize; i++) {
                words[offset + i] ^= keystream[i];
            }
        }
 
        return CFB;
    }());
 
 
    return CryptoJS.mode.CFB;
 
}));