55 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			55 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| 'use strict';
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| 
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| var assert = require('minimalistic-assert');
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| var inherits = require('inherits');
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| 
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| var Cipher = require('./cipher');
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| var DES = require('./des');
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| 
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| function EDEState(type, key) {
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|   assert.equal(key.length, 24, 'Invalid key length');
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| 
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|   var k1 = key.slice(0, 8);
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|   var k2 = key.slice(8, 16);
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|   var k3 = key.slice(16, 24);
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| 
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|   if (type === 'encrypt') {
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|     this.ciphers = [
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|       DES.create({ type: 'encrypt', key: k1 }),
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|       DES.create({ type: 'decrypt', key: k2 }),
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|       DES.create({ type: 'encrypt', key: k3 })
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|     ];
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|   } else {
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|     this.ciphers = [
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|       DES.create({ type: 'decrypt', key: k3 }),
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|       DES.create({ type: 'encrypt', key: k2 }),
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|       DES.create({ type: 'decrypt', key: k1 })
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|     ];
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|   }
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| }
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| 
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| function EDE(options) {
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|   Cipher.call(this, options);
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| 
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|   var state = new EDEState(this.type, this.options.key);
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|   this._edeState = state;
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| }
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| inherits(EDE, Cipher);
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| 
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| module.exports = EDE;
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| 
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| EDE.create = function create(options) {
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|   return new EDE(options);
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| };
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| 
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| EDE.prototype._update = function _update(inp, inOff, out, outOff) {
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|   var state = this._edeState;
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| 
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|   state.ciphers[0]._update(inp, inOff, out, outOff);
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|   state.ciphers[1]._update(out, outOff, out, outOff);
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|   state.ciphers[2]._update(out, outOff, out, outOff);
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| };
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| 
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| EDE.prototype._pad = DES.prototype._pad;
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| EDE.prototype._unpad = DES.prototype._unpad;
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