JavaAES加密实现
[java]?viewplaincopy
import?java.security.SecureRandom;??
??
import?javax.crypto.Cipher;??
import?javax.crypto.KeyGenerator;??
import?javax.crypto.SecretKey;??
import?javax.crypto.spec.SecretKeySpec;??
??
/?
??Usage:?
???
???
??String?crypto?=?AESUtil.encrypt(passwd,?cleartext)?
??...?
??String?cleartext?=?AESUtil.decrypt(passwd,?crypto)?
?? ?
???
??@author?mrsimple?
?/??
public?class?AESUtil?{??
????/?
??????@Title:?encrypt?
??????@Description:?AES加密?
??????@param?passwd?加密的密钥?
??????@param?originStr?需要加密的字符串?
??????@return?返回已加密的字符串?
??????@throws?Exception?
??????@throws?
?????/??
????public?static?String?encrypt(String?passwd,?String?originStr)?throws?Exception?{??
????????byte[]?rawKey?=?getRawKey(passwd.getBytes());??
????????byte[]?result?=?encrypt(rawKey,?originStr.getBytes());??
????????return?toHex(result);??
????}??
??
????/?
??????@Title:?decrypt?
??????@Description:?AES解密?
??????@param?passwd?加密的密钥?
??????@param?encrypted?已加密的密文?
??????@return?String?返回解密后的数据?
??????@throws?Exception?
??????@throws?
?????/??
????public?static?String?decrypt(String?passwd,?String?encrypted)?throws?Exception?{??
????????byte[]?rawKey?=?getRawKey(passwd.getBytes());??
????????byte[]?enc?=?toByte(encrypted);??
????????byte[]?result?=?decrypt(rawKey,?enc);??
????????return?new?String(result);??
????}??
??
????/?
??????@Title:?getRawKey?
??????@Description:?将密钥转换成字节数组?
??????@param?passwd?密钥字符串?
??????@return?byte[]?字节数组?
??????@throws?Exception?
??????@throws?
?????/??
????private?static?byte[]?getRawKey(byte[]?passwd)?throws?Exception?{??
????????KeyGenerator?kgen?=?KeyGenerator.getInstance("AES");??
????????SecureRandom?sr?=?SecureRandom.getInstance("SHA1PRNG");??
????????sr.setSeed(passwd);??
????????kgen.init(128,?sr);?//?192?and?256?bits?may?not?be?available??
????????SecretKey?skey?=?kgen.generateKey();??
????????byte[]?raw?=?skey.getEncoded();??
????????return?raw;??
????}??
??
????/?
??????@Title:?encrypt?
??????@Description:?加密字节数组?
??????@param?raw?密钥字节数组?
??????@param?originStr?明文字节数组?
??????@return?byte[]?加密后的字节数组?
??????@throws?Exception?
??????@throws?
?????/??
????private?static?byte[]?encrypt(byte[]?raw,?byte[]?originStr)?throws?Exception?{??
????????SecretKeySpec?skeySpec?=?new?SecretKeySpec(raw,?"AES");??
????????Cipher?cipher?=?Cipher.getInstance("AES");??
????????cipher.init(Cipher.ENCRYPT_MODE,?skeySpec);??
????????byte[]?encrypted?=?cipher.doFinal(originStr);??
????????return?encrypted;??
????}??
??
????/?
??????@Title:?decrypt?
??????@Description:?解密字节数组?
??????@param?passwd?密钥字节数组?
??????@param?encrypted?密文字节数组?
??????@return?byte[]?解密的字节数组?
??????@throws?Exception?
??????@throws?
?????/??
????private?static?byte[]?decrypt(byte[]?passwd,?byte[]?encrypted)?throws?Exception?{??
????????SecretKeySpec?skeySpec?=?new?SecretKeySpec(passwd,?"AES");??
????????Cipher?cipher?=?Cipher.getInstance("AES");??
????????cipher.init(Cipher.DECRYPT_MODE,?skeySpec);??
????????byte[]?decrypted?=?cipher.doFinal(encrypted);??
????????return?decrypted;??
????}??
??
????/?
??????@Title:?toHex?
??????@Description:将字符串转换成十六进制字符串?
??????@param?txt?
??????@return?
??????@throws?
?????/??
????public?static?String?toHex(String?txt)?{??
????????return?toHex(txt.getBytes());??
????}??
??
????/?
??????@Title:?fromHex?
??????@Description:??
???????????将十六进制字符串转换成普通字符串?
???????
??????@param?hex?
??????@return???????
??????@throws?
?????/??
????public?static?String?fromHex(String?hex)?{??
????????return?new?String(toByte(hex));??
????}??
??
????/?
??????@Title:?toByte?
??????@Description:??
???????????将字符串转换成字节数组??
???????
??????@param?hexString?
??????@return???????
??????@throws?
?????/??
????public?static?byte[]?toByte(String?hexString)?{??
????????int?len?=?hexString.length()?/?2;??
????????byte[]?result?=?new?byte[len];??
????????for?(int?i?=?0;?i?
????????????result[i]?=?Integer.valueOf(hexString.substring(2??i,?2??i?+?2),?16).byteValue();??
????????return?result;??
????}??
??
????/?
??????@Title:?toHex?
??????@Description:?
??????@param?buf?
??????@return?
??????@throws?
?????/??
????public?static?String?toHex(byte[]?buf)?{??
????????if?(buf?==?null)??
????????????return?"";??
????????StringBuffer?result?=?new?StringBuffer(2??buf.length);??
????????for?(int?i?=?0;?i?
????????????appendHex(result,?buf[i]);??
????????}??
????????return?result.toString();??
????}??
??
????private?final?static?String?HEX?=?"0123456789ABCDEF";??
????/?
??????@Title:?appendHex?
??????@Description:??
????????????
???????
??????@param?sb?
??????@param?b???????
??????@throws?
?????/??
????private?static?void?appendHex(StringBuffer?sb,?byte?b)?{??
????????sb.append(HEX.charAt((b?>>?4)?&?0x0f)).append(HEX.charAt(b?&?0x0f));??
????}??
??
}??
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