aboutsummaryrefslogblamecommitdiffstats
path: root/library/cryptojs/components/cipher-core.js
blob: 09862098f9bb2c8eec2a01b88ebb0d4900dcf550 (plain) (tree)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863






























































































































































































































































































































































































































































































































































































































































































































































































































































































                                                                                                                                                                  
/*
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 core components.
 */
CryptoJS.lib.Cipher || (function (undefined) {
    // Shortcuts
    var C = CryptoJS;
    var C_lib = C.lib;
    var Base = C_lib.Base;
    var WordArray = C_lib.WordArray;
    var BufferedBlockAlgorithm = C_lib.BufferedBlockAlgorithm;
    var C_enc = C.enc;
    var Utf8 = C_enc.Utf8;
    var Base64 = C_enc.Base64;
    var C_algo = C.algo;
    var EvpKDF = C_algo.EvpKDF;

    /**
     * Abstract base cipher template.
     *
     * @property {number} keySize This cipher's key size. Default: 4 (128 bits)
     * @property {number} ivSize This cipher's IV size. Default: 4 (128 bits)
     * @property {number} _ENC_XFORM_MODE A constant representing encryption mode.
     * @property {number} _DEC_XFORM_MODE A constant representing decryption mode.
     */
    var Cipher = C_lib.Cipher = BufferedBlockAlgorithm.extend({
        /**
         * Configuration options.
         *
         * @property {WordArray} iv The IV to use for this operation.
         */
        cfg: Base.extend(),

        /**
         * Creates this cipher in encryption mode.
         *
         * @param {WordArray} key The key.
         * @param {Object} cfg (Optional) The configuration options to use for this operation.
         *
         * @return {Cipher} A cipher instance.
         *
         * @static
         *
         * @example
         *
         *     var cipher = CryptoJS.algo.AES.createEncryptor(keyWordArray, { iv: ivWordArray });
         */
        createEncryptor: function (key, cfg) {
            return this.create(this._ENC_XFORM_MODE, key, cfg);
        },

        /**
         * Creates this cipher in decryption mode.
         *
         * @param {WordArray} key The key.
         * @param {Object} cfg (Optional) The configuration options to use for this operation.
         *
         * @return {Cipher} A cipher instance.
         *
         * @static
         *
         * @example
         *
         *     var cipher = CryptoJS.algo.AES.createDecryptor(keyWordArray, { iv: ivWordArray });
         */
        createDecryptor: function (key, cfg) {
            return this.create(this._DEC_XFORM_MODE, key, cfg);
        },

        /**
         * Initializes a newly created cipher.
         *
         * @param {number} xformMode Either the encryption or decryption transormation mode constant.
         * @param {WordArray} key The key.
         * @param {Object} cfg (Optional) The configuration options to use for this operation.
         *
         * @example
         *
         *     var cipher = CryptoJS.algo.AES.create(CryptoJS.algo.AES._ENC_XFORM_MODE, keyWordArray, { iv: ivWordArray });
         */
        init: function (xformMode, key, cfg) {
            // Apply config defaults
            this.cfg = this.cfg.extend(cfg);

            // Store transform mode and key
            this._xformMode = xformMode;
            this._key = key;

            // Set initial values
            this.reset();
        },

        /**
         * Resets this cipher to its initial state.
         *
         * @example
         *
         *     cipher.reset();
         */
        reset: function () {
            // Reset data buffer
            BufferedBlockAlgorithm.reset.call(this);

            // Perform concrete-cipher logic
            this._doReset();
        },

        /**
         * Adds data to be encrypted or decrypted.
         *
         * @param {WordArray|string} dataUpdate The data to encrypt or decrypt.
         *
         * @return {WordArray} The data after processing.
         *
         * @example
         *
         *     var encrypted = cipher.process('data');
         *     var encrypted = cipher.process(wordArray);
         */
        process: function (dataUpdate) {
            // Append
            this._append(dataUpdate);

            // Process available blocks
            return this._process();
        },

        /**
         * Finalizes the encryption or decryption process.
         * Note that the finalize operation is effectively a destructive, read-once operation.
         *
         * @param {WordArray|string} dataUpdate The final data to encrypt or decrypt.
         *
         * @return {WordArray} The data after final processing.
         *
         * @example
         *
         *     var encrypted = cipher.finalize();
         *     var encrypted = cipher.finalize('data');
         *     var encrypted = cipher.finalize(wordArray);
         */
        finalize: function (dataUpdate) {
            // Final data update
            if (dataUpdate) {
                this._append(dataUpdate);
            }

            // Perform concrete-cipher logic
            var finalProcessedData = this._doFinalize();

            return finalProcessedData;
        },

        keySize: 128/32,

        ivSize: 128/32,

        _ENC_XFORM_MODE: 1,

        _DEC_XFORM_MODE: 2,

        /**
         * Creates shortcut functions to a cipher's object interface.
         *
         * @param {Cipher} cipher The cipher to create a helper for.
         *
         * @return {Object} An object with encrypt and decrypt shortcut functions.
         *
         * @static
         *
         * @example
         *
         *     var AES = CryptoJS.lib.Cipher._createHelper(CryptoJS.algo.AES);
         */
        _createHelper: (function () {
            function selectCipherStrategy(key) {
                if (typeof key == 'string') {
                    return PasswordBasedCipher;
                } else {
                    return SerializableCipher;
                }
            }

            return function (cipher) {
                return {
                    encrypt: function (message, key, cfg) {
                        return selectCipherStrategy(key).encrypt(cipher, message, key, cfg);
                    },

                    decrypt: function (ciphertext, key, cfg) {
                        return selectCipherStrategy(key).decrypt(cipher, ciphertext, key, cfg);
                    }
                };
            };
        }())
    });

    /**
     * Abstract base stream cipher template.
     *
     * @property {number} blockSize The number of 32-bit words this cipher operates on. Default: 1 (32 bits)
     */
    var StreamCipher = C_lib.StreamCipher = Cipher.extend({
        _doFinalize: function () {
            // Process partial blocks
            var finalProcessedBlocks = this._process(!!'flush');

            return finalProcessedBlocks;
        },

        blockSize: 1
    });

    /**
     * Mode namespace.
     */
    var C_mode = C.mode = {};

    /**
     * Abstract base block cipher mode template.
     */
    var BlockCipherMode = C_lib.BlockCipherMode = Base.extend({
        /**
         * Creates this mode for encryption.
         *
         * @param {Cipher} cipher A block cipher instance.
         * @param {Array} iv The IV words.
         *
         * @static
         *
         * @example
         *
         *     var mode = CryptoJS.mode.CBC.createEncryptor(cipher, iv.words);
         */
        createEncryptor: function (cipher, iv) {
            return this.Encryptor.create(cipher, iv);
        },

        /**
         * Creates this mode for decryption.
         *
         * @param {Cipher} cipher A block cipher instance.
         * @param {Array} iv The IV words.
         *
         * @static
         *
         * @example
         *
         *     var mode = CryptoJS.mode.CBC.createDecryptor(cipher, iv.words);
         */
        createDecryptor: function (cipher, iv) {
            return this.Decryptor.create(cipher, iv);
        },

        /**
         * Initializes a newly created mode.
         *
         * @param {Cipher} cipher A block cipher instance.
         * @param {Array} iv The IV words.
         *
         * @example
         *
         *     var mode = CryptoJS.mode.CBC.Encryptor.create(cipher, iv.words);
         */
        init: function (cipher, iv) {
            this._cipher = cipher;
            this._iv = iv;
        }
    });

    /**
     * Cipher Block Chaining mode.
     */
    var CBC = C_mode.CBC = (function () {
        /**
         * Abstract base CBC mode.
         */
        var CBC = BlockCipherMode.extend();

        /**
         * CBC encryptor.
         */
        CBC.Encryptor = CBC.extend({
            /**
             * Processes the data block at offset.
             *
             * @param {Array} words The data words to operate on.
             * @param {number} offset The offset where the block starts.
             *
             * @example
             *
             *     mode.processBlock(data.words, offset);
             */
            processBlock: function (words, offset) {
                // Shortcuts
                var cipher = this._cipher;
                var blockSize = cipher.blockSize;

                // XOR and encrypt
                xorBlock.call(this, words, offset, blockSize);
                cipher.encryptBlock(words, offset);

                // Remember this block to use with next block
                this._prevBlock = words.slice(offset, offset + blockSize);
            }
        });

        /**
         * CBC decryptor.
         */
        CBC.Decryptor = CBC.extend({
            /**
             * Processes the data block at offset.
             *
             * @param {Array} words The data words to operate on.
             * @param {number} offset The offset where the block starts.
             *
             * @example
             *
             *     mode.processBlock(data.words, offset);
             */
            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);

                // Decrypt and XOR
                cipher.decryptBlock(words, offset);
                xorBlock.call(this, words, offset, blockSize);

                // This block becomes the previous block
                this._prevBlock = thisBlock;
            }
        });

        function xorBlock(words, offset, blockSize) {
            // Shortcut
            var iv = this._iv;

            // Choose mixing block
            if (iv) {
                var block = iv;

                // Remove IV for subsequent blocks
                this._iv = undefined;
            } else {
                var block = this._prevBlock;
            }

            // XOR blocks
            for (var i = 0; i < blockSize; i++) {
                words[offset + i] ^= block[i];
            }
        }

        return CBC;
    }());

    /**
     * Padding namespace.
     */
    var C_pad = C.pad = {};

    /**
     * PKCS #5/7 padding strategy.
     */
    var Pkcs7 = C_pad.Pkcs7 = {
        /**
         * Pads data using the algorithm defined in PKCS #5/7.
         *
         * @param {WordArray} data The data to pad.
         * @param {number} blockSize The multiple that the data should be padded to.
         *
         * @static
         *
         * @example
         *
         *     CryptoJS.pad.Pkcs7.pad(wordArray, 4);
         */
        pad: function (data, blockSize) {
            // Shortcut
            var blockSizeBytes = blockSize * 4;

            // Count padding bytes
            var nPaddingBytes = blockSizeBytes - data.sigBytes % blockSizeBytes;

            // Create padding word
            var paddingWord = (nPaddingBytes << 24) | (nPaddingBytes << 16) | (nPaddingBytes << 8) | nPaddingBytes;

            // Create padding
            var paddingWords = [];
            for (var i = 0; i < nPaddingBytes; i += 4) {
                paddingWords.push(paddingWord);
            }
            var padding = WordArray.create(paddingWords, nPaddingBytes);

            // Add padding
            data.concat(padding);
        },

        /**
         * Unpads data that had been padded using the algorithm defined in PKCS #5/7.
         *
         * @param {WordArray} data The data to unpad.
         *
         * @static
         *
         * @example
         *
         *     CryptoJS.pad.Pkcs7.unpad(wordArray);
         */
        unpad: function (data) {
            // Get number of padding bytes from last byte
            var nPaddingBytes = data.words[(data.sigBytes - 1) >>> 2] & 0xff;

            // Remove padding
            data.sigBytes -= nPaddingBytes;
        }
    };

    /**
     * Abstract base block cipher template.
     *
     * @property {number} blockSize The number of 32-bit words this cipher operates on. Default: 4 (128 bits)
     */
    var BlockCipher = C_lib.BlockCipher = Cipher.extend({
        /**
         * Configuration options.
         *
         * @property {Mode} mode The block mode to use. Default: CBC
         * @property {Padding} padding The padding strategy to use. Default: Pkcs7
         */
        cfg: Cipher.cfg.extend({
            mode: CBC,
            padding: Pkcs7
        }),

        reset: function () {
            // Reset cipher
            Cipher.reset.call(this);

            // Shortcuts
            var cfg = this.cfg;
            var iv = cfg.iv;
            var mode = cfg.mode;

            // Reset block mode
            if (this._xformMode == this._ENC_XFORM_MODE) {
                var modeCreator = mode.createEncryptor;
            } else /* if (this._xformMode == this._DEC_XFORM_MODE) */ {
                var modeCreator = mode.createDecryptor;

                // Keep at least one block in the buffer for unpadding
                this._minBufferSize = 1;
            }
            this._mode = modeCreator.call(mode, this, iv && iv.words);
        },

        _doProcessBlock: function (words, offset) {
            this._mode.processBlock(words, offset);
        },

        _doFinalize: function () {
            // Shortcut
            var padding = this.cfg.padding;

            // Finalize
            if (this._xformMode == this._ENC_XFORM_MODE) {
                // Pad data
                padding.pad(this._data, this.blockSize);

                // Process final blocks
                var finalProcessedBlocks = this._process(!!'flush');
            } else /* if (this._xformMode == this._DEC_XFORM_MODE) */ {
                // Process final blocks
                var finalProcessedBlocks = this._process(!!'flush');

                // Unpad data
                padding.unpad(finalProcessedBlocks);
            }

            return finalProcessedBlocks;
        },

        blockSize: 128/32
    });

    /**
     * A collection of cipher parameters.
     *
     * @property {WordArray} ciphertext The raw ciphertext.
     * @property {WordArray} key The key to this ciphertext.
     * @property {WordArray} iv The IV used in the ciphering operation.
     * @property {WordArray} salt The salt used with a key derivation function.
     * @property {Cipher} algorithm The cipher algorithm.
     * @property {Mode} mode The block mode used in the ciphering operation.
     * @property {Padding} padding The padding scheme used in the ciphering operation.
     * @property {number} blockSize The block size of the cipher.
     * @property {Format} formatter The default formatting strategy to convert this cipher params object to a string.
     */
    var CipherParams = C_lib.CipherParams = Base.extend({
        /**
         * Initializes a newly created cipher params object.
         *
         * @param {Object} cipherParams An object with any of the possible cipher parameters.
         *
         * @example
         *
         *     var cipherParams = CryptoJS.lib.CipherParams.create({
         *         ciphertext: ciphertextWordArray,
         *         key: keyWordArray,
         *         iv: ivWordArray,
         *         salt: saltWordArray,
         *         algorithm: CryptoJS.algo.AES,
         *         mode: CryptoJS.mode.CBC,
         *         padding: CryptoJS.pad.PKCS7,
         *         blockSize: 4,
         *         formatter: CryptoJS.format.OpenSSL
         *     });
         */
        init: function (cipherParams) {
            this.mixIn(cipherParams);
        },

        /**
         * Converts this cipher params object to a string.
         *
         * @param {Format} formatter (Optional) The formatting strategy to use.
         *
         * @return {string} The stringified cipher params.
         *
         * @throws Error If neither the formatter nor the default formatter is set.
         *
         * @example
         *
         *     var string = cipherParams + '';
         *     var string = cipherParams.toString();
         *     var string = cipherParams.toString(CryptoJS.format.OpenSSL);
         */
        toString: function (formatter) {
            return (formatter || this.formatter).stringify(this);
        }
    });

    /**
     * Format namespace.
     */
    var C_format = C.format = {};

    /**
     * OpenSSL formatting strategy.
     */
    var OpenSSLFormatter = C_format.OpenSSL = {
        /**
         * Converts a cipher params object to an OpenSSL-compatible string.
         *
         * @param {CipherParams} cipherParams The cipher params object.
         *
         * @return {string} The OpenSSL-compatible string.
         *
         * @static
         *
         * @example
         *
         *     var openSSLString = CryptoJS.format.OpenSSL.stringify(cipherParams);
         */
        stringify: function (cipherParams) {
            // Shortcuts
            var ciphertext = cipherParams.ciphertext;
            var salt = cipherParams.salt;

            // Format
            if (salt) {
                var wordArray = WordArray.create([0x53616c74, 0x65645f5f]).concat(salt).concat(ciphertext);
            } else {
                var wordArray = ciphertext;
            }

            return wordArray.toString(Base64);
        },

        /**
         * Converts an OpenSSL-compatible string to a cipher params object.
         *
         * @param {string} openSSLStr The OpenSSL-compatible string.
         *
         * @return {CipherParams} The cipher params object.
         *
         * @static
         *
         * @example
         *
         *     var cipherParams = CryptoJS.format.OpenSSL.parse(openSSLString);
         */
        parse: function (openSSLStr) {
            // Parse base64
            var ciphertext = Base64.parse(openSSLStr);

            // Shortcut
            var ciphertextWords = ciphertext.words;

            // Test for salt
            if (ciphertextWords[0] == 0x53616c74 && ciphertextWords[1] == 0x65645f5f) {
                // Extract salt
                var salt = WordArray.create(ciphertextWords.slice(2, 4));

                // Remove salt from ciphertext
                ciphertextWords.splice(0, 4);
                ciphertext.sigBytes -= 16;
            }

            return CipherParams.create({ ciphertext: ciphertext, salt: salt });
        }
    };

    /**
     * A cipher wrapper that returns ciphertext as a serializable cipher params object.
     */
    var SerializableCipher = C_lib.SerializableCipher = Base.extend({
        /**
         * Configuration options.
         *
         * @property {Formatter} format The formatting strategy to convert cipher param objects to and from a string. Default: OpenSSL
         */
        cfg: Base.extend({
            format: OpenSSLFormatter
        }),

        /**
         * Encrypts a message.
         *
         * @param {Cipher} cipher The cipher algorithm to use.
         * @param {WordArray|string} message The message to encrypt.
         * @param {WordArray} key The key.
         * @param {Object} cfg (Optional) The configuration options to use for this operation.
         *
         * @return {CipherParams} A cipher params object.
         *
         * @static
         *
         * @example
         *
         *     var ciphertextParams = CryptoJS.lib.SerializableCipher.encrypt(CryptoJS.algo.AES, message, key);
         *     var ciphertextParams = CryptoJS.lib.SerializableCipher.encrypt(CryptoJS.algo.AES, message, key, { iv: iv });
         *     var ciphertextParams = CryptoJS.lib.SerializableCipher.encrypt(CryptoJS.algo.AES, message, key, { iv: iv, format: CryptoJS.format.OpenSSL });
         */
        encrypt: function (cipher, message, key, cfg) {
            // Apply config defaults
            cfg = this.cfg.extend(cfg);

            // Encrypt
            var encryptor = cipher.createEncryptor(key, cfg);
            var ciphertext = encryptor.finalize(message);

            // Shortcut
            var cipherCfg = encryptor.cfg;

            // Create and return serializable cipher params
            return CipherParams.create({
                ciphertext: ciphertext,
                key: key,
                iv: cipherCfg.iv,
                algorithm: cipher,
                mode: cipherCfg.mode,
                padding: cipherCfg.padding,
                blockSize: cipher.blockSize,
                formatter: cfg.format
            });
        },

        /**
         * Decrypts serialized ciphertext.
         *
         * @param {Cipher} cipher The cipher algorithm to use.
         * @param {CipherParams|string} ciphertext The ciphertext to decrypt.
         * @param {WordArray} key The key.
         * @param {Object} cfg (Optional) The configuration options to use for this operation.
         *
         * @return {WordArray} The plaintext.
         *
         * @static
         *
         * @example
         *
         *     var plaintext = CryptoJS.lib.SerializableCipher.decrypt(CryptoJS.algo.AES, formattedCiphertext, key, { iv: iv, format: CryptoJS.format.OpenSSL });
         *     var plaintext = CryptoJS.lib.SerializableCipher.decrypt(CryptoJS.algo.AES, ciphertextParams, key, { iv: iv, format: CryptoJS.format.OpenSSL });
         */
        decrypt: function (cipher, ciphertext, key, cfg) {
            // Apply config defaults
            cfg = this.cfg.extend(cfg);

            // Convert string to CipherParams
            ciphertext = this._parse(ciphertext, cfg.format);

            // Decrypt
            var plaintext = cipher.createDecryptor(key, cfg).finalize(ciphertext.ciphertext);

            return plaintext;
        },

        /**
         * Converts serialized ciphertext to CipherParams,
         * else assumed CipherParams already and returns ciphertext unchanged.
         *
         * @param {CipherParams|string} ciphertext The ciphertext.
         * @param {Formatter} format The formatting strategy to use to parse serialized ciphertext.
         *
         * @return {CipherParams} The unserialized ciphertext.
         *
         * @static
         *
         * @example
         *
         *     var ciphertextParams = CryptoJS.lib.SerializableCipher._parse(ciphertextStringOrParams, format);
         */
        _parse: function (ciphertext, format) {
            if (typeof ciphertext == 'string') {
                return format.parse(ciphertext, this);
            } else {
                return ciphertext;
            }
        }
    });

    /**
     * Key derivation function namespace.
     */
    var C_kdf = C.kdf = {};

    /**
     * OpenSSL key derivation function.
     */
    var OpenSSLKdf = C_kdf.OpenSSL = {
        /**
         * Derives a key and IV from a password.
         *
         * @param {string} password The password to derive from.
         * @param {number} keySize The size in words of the key to generate.
         * @param {number} ivSize The size in words of the IV to generate.
         * @param {WordArray|string} salt (Optional) A 64-bit salt to use. If omitted, a salt will be generated randomly.
         *
         * @return {CipherParams} A cipher params object with the key, IV, and salt.
         *
         * @static
         *
         * @example
         *
         *     var derivedParams = CryptoJS.kdf.OpenSSL.execute('Password', 256/32, 128/32);
         *     var derivedParams = CryptoJS.kdf.OpenSSL.execute('Password', 256/32, 128/32, 'saltsalt');
         */
        execute: function (password, keySize, ivSize, salt) {
            // Generate random salt
            if (!salt) {
                salt = WordArray.random(64/8);
            }

            // Derive key and IV
            var key = EvpKDF.create({ keySize: keySize + ivSize }).compute(password, salt);

            // Separate key and IV
            var iv = WordArray.create(key.words.slice(keySize), ivSize * 4);
            key.sigBytes = keySize * 4;

            // Return params
            return CipherParams.create({ key: key, iv: iv, salt: salt });
        }
    };

    /**
     * A serializable cipher wrapper that derives the key from a password,
     * and returns ciphertext as a serializable cipher params object.
     */
    var PasswordBasedCipher = C_lib.PasswordBasedCipher = SerializableCipher.extend({
        /**
         * Configuration options.
         *
         * @property {KDF} kdf The key derivation function to use to generate a key and IV from a password. Default: OpenSSL
         */
        cfg: SerializableCipher.cfg.extend({
            kdf: OpenSSLKdf
        }),

        /**
         * Encrypts a message using a password.
         *
         * @param {Cipher} cipher The cipher algorithm to use.
         * @param {WordArray|string} message The message to encrypt.
         * @param {string} password The password.
         * @param {Object} cfg (Optional) The configuration options to use for this operation.
         *
         * @return {CipherParams} A cipher params object.
         *
         * @static
         *
         * @example
         *
         *     var ciphertextParams = CryptoJS.lib.PasswordBasedCipher.encrypt(CryptoJS.algo.AES, message, 'password');
         *     var ciphertextParams = CryptoJS.lib.PasswordBasedCipher.encrypt(CryptoJS.algo.AES, message, 'password', { format: CryptoJS.format.OpenSSL });
         */
        encrypt: function (cipher, message, password, cfg) {
            // Apply config defaults
            cfg = this.cfg.extend(cfg);

            // Derive key and other params
            var derivedParams = cfg.kdf.execute(password, cipher.keySize, cipher.ivSize);

            // Add IV to config
            cfg.iv = derivedParams.iv;

            // Encrypt
            var ciphertext = SerializableCipher.encrypt.call(this, cipher, message, derivedParams.key, cfg);

            // Mix in derived params
            ciphertext.mixIn(derivedParams);

            return ciphertext;
        },

        /**
         * Decrypts serialized ciphertext using a password.
         *
         * @param {Cipher} cipher The cipher algorithm to use.
         * @param {CipherParams|string} ciphertext The ciphertext to decrypt.
         * @param {string} password The password.
         * @param {Object} cfg (Optional) The configuration options to use for this operation.
         *
         * @return {WordArray} The plaintext.
         *
         * @static
         *
         * @example
         *
         *     var plaintext = CryptoJS.lib.PasswordBasedCipher.decrypt(CryptoJS.algo.AES, formattedCiphertext, 'password', { format: CryptoJS.format.OpenSSL });
         *     var plaintext = CryptoJS.lib.PasswordBasedCipher.decrypt(CryptoJS.algo.AES, ciphertextParams, 'password', { format: CryptoJS.format.OpenSSL });
         */
        decrypt: function (cipher, ciphertext, password, cfg) {
            // Apply config defaults
            cfg = this.cfg.extend(cfg);

            // Convert string to CipherParams
            ciphertext = this._parse(ciphertext, cfg.format);

            // Derive key and other params
            var derivedParams = cfg.kdf.execute(password, cipher.keySize, cipher.ivSize, ciphertext.salt);

            // Add IV to config
            cfg.iv = derivedParams.iv;

            // Decrypt
            var plaintext = SerializableCipher.decrypt.call(this, cipher, ciphertext, derivedParams.key, cfg);

            return plaintext;
        }
    });
}());