要在Flex中实现AES加密，可以通过as3crypto实现。但是as3crypto本身的用法比较复杂，一般是封装一下再调用。
下面是9RIA上的一篇文章给出的一个实现，使用中稍感不方便（见注释）：
1: package {2: import com.hurlant.crypto.Crypto;
3: import com.hurlant.crypto.prng.Random;
4: import com.hurlant.crypto.symmetric.ICipher;
5: import com.hurlant.crypto.symmetric.IPad;
6: import com.hurlant.crypto.symmetric.IVMode;
7: import com.hurlant.crypto.symmetric.PKCS5;
8: import com.hurlant.util.Base64;
9: import com.hurlant.util.Hex;
10:
11: import flash.utils.ByteArray;
12:
13: /**
14: * AES 算法的加密解密工具类。
15: *
16: * @author Fuchun
17: * @langversion 3.0
18: * @playerversion Flash 11.1
19: * @productversion 1.0
20: */
21: public class AES {22:
23: /**
24: * 默认的算法与模式名称。
25: */
26: public static const DEFAULT_CIPHER_NAME:String = "aes-128-cbc";
27:
28: /**
29: * 默认的填充模式。<code>pkcs5</code>
30: */
31: public static const DEFAULT_PADNAME:String = "pkcs5";
32:
33: /**
34: * 无填充。
35: */
36: public static const NULL_PADDING:String = "null";
37:
38: private static const RAND:Random = new Random();
39:
40: private var _name:String;
41: // 密钥
42: private var _key:ByteArray;
43: // 向量
44: private var _iv:ByteArray;
45: // 填充模式
46: private var _padName:String;
47: private var _enc:ICipher;
48: private var _dec:ICipher;
49:
50: public function AES(key:ByteArray, iv:ByteArray = null, name:String = DEFAULT_CIPHER_NAME, padName:String = DEFAULT_PADNAME) {51: _name = name;
52: _key = key;
53: _iv = iv;
54: _padName = padName;
55: init();
56: }
57:
58: private function init():void {59: var _pad:IPad = Crypto.getPad(_padName);
60: _enc = Crypto.getCipher(_name, _key, _pad);
61: _dec = Crypto.getCipher(_name, _key, _pad);
62: if (iv) { 63: if (_enc is IVMode) {64: var encIvm:IVMode = _enc as IVMode;
65: encIvm.IV = iv;
66: }
67: if (_dec is IVMode) {68: var decIvm:IVMode = _dec as IVMode;
69: decIvm.IV = iv;
70: }
71: }
72: }
73:
74: public static function generateKey(name:String):ByteArray {75: var keyLength:uint = Crypto.getKeySize(name);
76: var key:ByteArray = new ByteArray();
77: RAND.nextBytes(key, keyLength);
78: return key;
79: }
80:
81: public static function generateIV(name:String, key:ByteArray):ByteArray {82: var cipher:ICipher = Crypto.getCipher(name, key);
83: var iv:ByteArray = new ByteArray();
84: RAND.nextBytes(iv, cipher.getBlockSize());
85: return iv;
86: }
87:
88: public function encrypt(input:ByteArray):ByteArray {89: var src:ByteArray = new ByteArray();
90: var result:ByteArray = new ByteArray();
91: src.writeBytes(input, 0, input.length);
92:
93: _enc.encrypt(input);
94: result.writeBytes(input, 0, input.length);
95: input.length = 0;
96: input.writeBytes(src, 0, src.length);
97:
98: src.clear();
99: return result;
100: }
101:
102: public function decrypt(input:ByteArray):ByteArray {103: var src:ByteArray = new ByteArray();
104: var result:ByteArray = new ByteArray();
105: src.writeBytes(input, 0, input.length);
106:
107: _dec.decrypt(input);
108: result.writeBytes(input, 0, input.length);
109: input.length = 0;
110: input.writeBytes(src, 0, src.length);
111:
112: src.clear();
113: return result;
114: }
115:
116: public function encryptString(input:String):ByteArray { 117: if (!input || !input.length) {118: return null;
119: }
120: var inputBytes:ByteArray = new ByteArray();
121: inputBytes.writeUTFBytes(input);
122: return encrypt(inputBytes);
123: }
124:
125: //无配对的解密方法，加密后的结果无法直接用decryptString2Hex解密
126: public function encryptString2Hex(input:String):String {127: var result:ByteArray = encryptString(input);
128: return Hex.fromArray(result);
129: }
130:
131: //无配对的解密方法，加密后的结果无法直接用decryptString2Hex解密
132: public function encryptString2Base64(input:String):String {133: var result:ByteArray = encryptString(input);
134: return Base64.encodeByteArray(result);
135: }
136:
137: //代码中我们一般习惯直接加密字符串，加密后直接得到密文字符串，这里没有提供这个方法
138:
139: public function decryptString(input:String):ByteArray { 140: if (!input || !input.length) {141: return null;
142: }
143: var inputBytes:ByteArray = new ByteArray();
144: inputBytes.writeUTFBytes(input);
145: return decrypt(inputBytes);
146: }
147:
148: public function decryptString2Hex(input:String):String {149: var result:ByteArray = decryptString(input);
150: return Hex.fromArray(result);
151: }
152:
153: public function decryptString2Base64(input:String):String {154: var result:ByteArray = decryptString(input);
155: return Base64.encodeByteArray(result);
156: }
157:
158: public function set iv(value:ByteArray):void {159: _iv = value;
160: }
161: public function get iv():ByteArray {162: return _iv;
163: }
164: }
165: }
下面是我修改后的代码：
1: package utility
2: {3: import com.hurlant.crypto.Crypto;
4: import com.hurlant.crypto.prng.Random;
5: import com.hurlant.crypto.symmetric.ICipher;
6: import com.hurlant.crypto.symmetric.IPad;
7: import com.hurlant.crypto.symmetric.IVMode;
8: import com.hurlant.crypto.symmetric.PKCS5;
9: import com.hurlant.util.Base64;
10: import com.hurlant.util.Hex;
11:
12: import flash.utils.ByteArray;
13:
14: /**
15: * AES 算法的加密解密工具类。
16: *
17: * @author Fuchun，modified by caichengyang
18: * @langversion 3.0
19: * @playerversion Flash 11.1
20: * @productversion 1.0
21: */
22: public class AES {23:
24: /**
25: * 默认的算法与模式名称。
26: */
27: public static const DEFAULT_CIPHER_NAME:String = "aes-128-cbc";
28:
29: /**
30: * 默认的填充模式。<code>pkcs5</code>
31: */
32: public static const DEFAULT_PADNAME:String = "pkcs5";
33:
34: /**
35: * 无填充。
36: */
37: public static const NULL_PADDING:String = "null";
38:
39: private static const RAND:Random = new Random();
40:
41: private var _name:String;
42: // 密钥
43: private var _key:ByteArray;
44: // 向量
45: private var _iv:ByteArray;
46: // 填充模式
47: private var _padName:String;
48: private var _enc:ICipher;
49: private var _dec:ICipher;
50:
51: public function AES(key:ByteArray, iv:ByteArray = null,
52: name:String = DEFAULT_CIPHER_NAME,
53: padName:String = DEFAULT_PADNAME) {54: _name = name;
55: _key = key;
56: _iv = iv;
57: _padName = padName;
58: init();
59: }
60:
61: private function init():void {62: var _pad:IPad = Crypto.getPad(_padName);
63: _enc = Crypto.getCipher(_name, _key, _pad);
64: _dec = Crypto.getCipher(_name, _key, _pad);
65: if (iv) { 66: if (_enc is IVMode) {67: var encIvm:IVMode = _enc as IVMode;
68: encIvm.IV = iv;
69: }
70: if (_dec is IVMode) {71: var decIvm:IVMode = _dec as IVMode;
72: decIvm.IV = iv;
73: }
74: }
75: }
76:
77: public static function generateKey(name:String):ByteArray {78: var keyLength:uint = Crypto.getKeySize(name);
79: var key:ByteArray = new ByteArray();
80: RAND.nextBytes(key, keyLength);
81: return key;
82: }
83:
84: public static function generateIV(name:String, key:ByteArray):ByteArray {85: var cipher:ICipher = Crypto.getCipher(name, key);
86: var iv:ByteArray = new ByteArray();
87: RAND.nextBytes(iv, cipher.getBlockSize());
88: return iv;
89: }
90:
91: public function set iv(value:ByteArray):void {92: _iv = value;
93: }
94:
95: public function get iv():ByteArray {96: return _iv;
97: }
98:
99:
100: // base functions
101: public function encrypt(input:ByteArray):ByteArray {102: var src:ByteArray = new ByteArray();
103: var result:ByteArray = new ByteArray();
104: src.writeBytes(input, 0, input.length);
105:
106: _enc.encrypt(input);
107: result.writeBytes(input, 0, input.length);
108: input.length = 0;
109: input.writeBytes(src, 0, src.length);
110:
111: src.clear();
112: return result;
113: }
114:
115: public function decrypt(input:ByteArray):ByteArray {116: var src:ByteArray = new ByteArray();
117: var result:ByteArray = new ByteArray();
118: src.writeBytes(input, 0, input.length);
119:
120: _dec.decrypt(input);
121: result.writeBytes(input, 0, input.length);
122: input.length = 0;
123: input.writeBytes(src, 0, src.length);
124:
125: src.clear();
126: return result;
127: }
128:
129:
130: // encrypt string
131: public function encryptString(input:String):ByteArray { 132: if (!input || !input.length) {133: return null;
134: }
135: var inputBytes:ByteArray = new ByteArray();
136: inputBytes.writeUTFBytes(input);
137: return encrypt(inputBytes);
138: }
139:
140: public function encryptString2Hex(input:String):String {141: var result:ByteArray = encryptString(input);
142: return Hex.fromArray(result);
143: }
144:
145: public function encryptString2Base64(input:String):String {146: var result:ByteArray = encryptString(input);
147: return Base64.encodeByteArray(result);
148: }
149:
150:
151: // decrypt string
152: public function decryptString(input:ByteArray):String {153: var decryptBytes:ByteArray = decrypt(input);
154: decryptBytes.position = 0;
155: var result:String = decryptBytes.readUTFBytes(decryptBytes.length);
156: return result;
157: }
158:
159: public function decryptStringFromHex(input:String):String {160: var inputBytes:ByteArray = Hex.toArray(input);
161: var result:String = decryptString(inputBytes);
162: return result;
163: }
164:
165: public function decryptStringFromBase64(input:String):String {166: var inputBytes:ByteArray = Base64.decodeToByteArray(input);
167: var result:String = decryptString(inputBytes);
168: return result;
169: }
170:
171:
172: }
173: }
用法如下：
1: protected function btnEncrypt_clickHandler(event:MouseEvent):void
2: {3:
4: var key : ByteArray = Hex.toArray("f056180ec970b169980f108c13305642"); //AES.generateKey(AES.DEFAULT_CIPHER_NAME); 5: var iv : ByteArray = Hex.toArray("912467427aa54cccf443d2ae206a63ce"); //AES.generateIV(AES.DEFAULT_CIPHER_NAME, key);6:
7: lblText.text = lblText.text + "key:" + Hex.fromArray(key) + "\r\n";
8: lblText.text = lblText.text + "iv:" + Hex.fromArray(iv) + "\r\n";
9:
10: var aes : AES = new AES(key, iv, "aes-128-cbc", "null");
11:
12: var plainText:String = "caichengyang";
13:
14: var s1:String = aes.encryptString2Base64(plainText);
15:
16: var s2:String = aes.decryptStringFromBase64(s1);
17:
18: lblText.text = lblText.text + "加密后：" + s1 + "\r\n" + "解密后：" + s2 + "\r\n\r\n";
19: }
运行效果如下：