开发中经常遇到这样的场景：在服务器端对数据进行加密，客户端进行解密，这样可以有效的防止数据在传输过程中被截取，客户端和服务器采用相同的密钥进行加解密，AES加密算法是个不错的选择。
php算法
"; echo Security::decrypt($a, $key); class Security { public static function encrypt($input, $key) { $size = mcrypt_get_block_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_ECB); $input = Security::pkcs5_pad($input, $size); $td = mcrypt_module_open(MCRYPT_RIJNDAEL_128, '', MCRYPT_MODE_ECB, ''); $iv = mcrypt_create_iv(mcrypt_enc_get_iv_size($td), MCRYPT_RAND); mcrypt_generic_init($td, $key, $iv); $data = mcrypt_generic($td, $input); mcrypt_generic_deinit($td); mcrypt_module_close($td); $data = base64_encode($data); return $data; } private static function pkcs5_pad($text, $blocksize) { $pad = $blocksize - (strlen($text) % $blocksize); return $text . str_repeat(chr($pad), $pad); } public static function decrypt($sStr, $sKey) { $decrypted = mcrypt_decrypt( MCRYPT_RIJNDAEL_128, $sKey, base64_decode($sStr), MCRYPT_MODE_ECB ); $dec_s = strlen($decrypted); $padding = ord($decrypted[$dec_s - 1]); $decrypted = substr($decrypted, 0, -$padding); return $decrypted; } } ?>php进行AES加密需要依赖mcrypt扩展，如果上述代码运行报错，请在php.ini中开启mcrypt。
去掉前面的分号 extension=php_mcrypt.dll
android算法
import java.security.Key; import javax.crypto.Cipher; import javax.crypto.spec.SecretKeySpec; public class CryptAES { private static final String AESTYPE = "AES/ECB/PKCS5Padding"; public static String AESEncrypt(String keyStr, String plainText) { byte[] encrypt = null; try { Key key = generateKey(keyStr); Cipher cipher = Cipher.getInstance(AESTYPE); cipher.init(Cipher.ENCRYPTMODE, key); encrypt = cipher.doFinal(plainText.getBytes()); } catch (Exception e) { e.printStackTrace(); } return new String(Base64.encode(encrypt)); } public static String AESDecrypt(String keyStr, String encryptData) { byte[] decrypt = null; try { Key key = generateKey(keyStr); Cipher cipher = Cipher.getInstance(AESTYPE); cipher.init(Cipher.DECRYPTMODE, key); decrypt = cipher.doFinal(Base64.decode(encryptData)); } catch (Exception e) { e.printStackTrace(); } return new String(decrypt).trim(); } private static Key generateKey(String key) throws Exception { try { SecretKeySpec keySpec = new SecretKeySpec(key.getBytes(), "AES"); return keySpec; } catch (Exception e) { e.printStackTrace(); throw e; } } }
Base64.java
import java.io.ByteArrayOutputStream; public class Base64 { private static char[] base64EncodeChars = new char[]{'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'}; private static byte[] base64DecodeChars = new byte[]{-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, -1, 0, 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, -1, -1, -1, -1, -1, -1, 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, -1, -1, -1, -1, -1}; private Base64() { } public static String encode(byte[] data) { StringBuffer sb = new StringBuffer(); int len = data.length; int i = 0; int b1, b2, b3; while (i < len) { b1 = data[i++] & 0xff; if (i len) { sb.append(base64EncodeChars[b1 >>> 2]); sb.append(base64EncodeChars[(b1 & 0x3) << 4]); sb.append(""); break; } b2 = data[i++] & 0xff; if (i len) { sb.append(base64EncodeChars[b1 >>> 2]); sb.append(base64EncodeChars[((b1 & 0x03) << 4) | ((b2 & 0xf0) >>> 4)]); sb.append(base64EncodeChars[(b2 & 0x0f) << 2]); sb.append("="); break; } b3 = data[i++] & 0xff; sb.append(base64EncodeChars[b1 >>> 2]); sb.append(base64EncodeChars[((b1 & 0x03) << 4) | ((b2 & 0xf0) >>> 4)]); sb.append(base64EncodeChars[((b2 & 0x0f) << 2) | ((b3 & 0xc0) >>> 6)]); sb.append(base64EncodeChars[b3 & 0x3f]); } return sb.toString(); } public static byte[] decode(String str) { byte[] data = str.getBytes(); int len = data.length; ByteArrayOutputStream buf = new ByteArrayOutputStream(len); int i = 0; int b1, b2, b3, b4; while (i < len) { /* b1 / do { b1 = base64DecodeChars[data[i++]]; } while (i < len && b1 -1); if (b1 -1) { break; } / b2 / do { b2 = base64DecodeChars[data[i++]]; } while (i < len && b2 -1); if (b2 -1) { break; } buf.write((int) ((b1 << 2) | ((b2 & 0x30) >>> 4))); / b3 / do { b3 = data[i++]; if (b3 61) { return buf.toByteArray(); } b3 = base64DecodeChars[b3]; } while (i < len && b3 -1); if (b3 -1) { break; } buf.write((int) (((b2 & 0x0f) << 4) | ((b3 & 0x3c) >>> 2))); / b4 */ do { b4 = data[i++]; if (b4 61) { return buf.toByteArray(); } b4 = base64DecodeChars[b4]; } while (i < len && b4 -1); if (b4 == -1) { break; } buf.write((int) (((b3 & 0x03) << 6) | b4)); } return buf.toByteArray(); } }