整理的AES对称加密和RSA非对称加密

项目用到这两个加密方法，就整理了下做了个demo，这里也贴出来代码供参考

AES加密解密

public class AESUtil {
/**
* 生成AES密钥
* @param strkey
* @return
* @throws Exception
*/
public static String createKeyPairs(String strkey) throws  Exception {
KeyGenerator kgen = KeyGenerator.getInstance("AES");
// SHA1PRNG 强随机种子算法, 要区别4.2以上版本的调用方法
SecureRandom sr = null;
if (android.os.Build.VERSION.SDK_INT >= 17){
sr = SecureRandom.getInstance("SHA1PRNG", "Crypto");
}else{
sr = SecureRandom.getInstance("SHA1PRNG");
}
sr.setSeed(strkey.getBytes("UTF-8"));
kgen.init(128, sr); //256 bits or 128 bits,192bits
SecretKey skey = kgen.generateKey();
byte[] raw = skey.getEncoded();
Log.e("AES----KEY",new String(raw,"UTF-8"));
return new String(raw);
}
/**
* AES加密，传入需要加密的明文和key
* @param key
* @param src
* @return
* @throws Exception
*/
public static String encrypt(String key, String src) throws Exception {
byte[] result = encrypt(key.getBytes("UTF-8"), src.getBytes("UTF-8"));
return Base64.encodeToString(result, Base64.DEFAULT);
}
private static byte[] encrypt(byte[] key, byte[] src) throws Exception {
SecretKeySpec skeySpec = new SecretKeySpec(key, "AES");
Cipher cipher = Cipher.getInstance("AES");
cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
byte[] encrypted = cipher.doFinal(src);
return encrypted;
}

/**
* AES解密，传入密文和对应的key
* @param key
* @param encrypted
* @return
* @throws Exception
*/
public static String decrypt(String key, String encrypted) throws Exception {
byte[] result = decrypt(key.getBytes(), Base64.decode(encrypted, Base64.DEFAULT));
return new String(result,"UTF-8");
}
private static byte[] decrypt(byte[] key, byte[] encrypted) throws Exception {
SecretKeySpec skeySpec = new SecretKeySpec(key, "AES");
Cipher cipher = Cipher.getInstance("AES");
cipher.init(Cipher.DECRYPT_MODE, skeySpec);
byte[] decrypted = cipher.doFinal(encrypted);
return decrypted;
}
}

RSA加密解密

public class RSAUtil {
/**
* 生成经BASE64编码后的RSA公钥和私钥
*/
public static void createKeyPairs() {
try {
KeyPairGenerator generator = KeyPairGenerator.getInstance("RSA");
generator.initialize(1024, new SecureRandom());
KeyPair pair = generator.generateKeyPair();
PublicKey pubKey = pair.getPublic();
PrivateKey privKey = pair.getPrivate();
byte[] pubk = pubKey.getEncoded();
byte[] privk = privKey.getEncoded();
// base64编码，屏蔽特殊字符
String strpk = new String(Base64.encode(pubk,Base64.DEFAULT));
String strprivk = new String(Base64.encode(privk,Base64.DEFAULT));
Log.e("strpk", strpk);
Log.e("strprivk", strprivk);
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* RSA公钥加密
* @param content	待加密的明文
* @param pubKey	RSA公钥
* @return	经BASE64编码后的密文
*/
public static String pubKeyEnc(String content,String pubKey){
try {
KeyFactory keyf = KeyFactory.getInstance("RSA","BC");
//获取公钥
InputStream is = new ByteArrayInputStream(pubKey.getBytes("utf-8"));
byte[] pubbytes = new byte[new Long(pubKey.length()).intValue()];
is.read(pubbytes);
X509EncodedKeySpec pubX509 = new X509EncodedKeySpec(Base64.decode(pubbytes,Base64.DEFAULT));
PublicKey pkey = keyf.generatePublic(pubX509);

//公钥加密
Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
cipher.init(Cipher.ENCRYPT_MODE, pkey);
byte[] cipherText = cipher.doFinal(content.getBytes());
// 将加密结果转换为Base64编码结果；便于internet传送
return Base64.encodeToString(cipherText,Base64.DEFAULT);
} catch (Exception e) {
e.printStackTrace();
throw new RuntimeException(e);
}
}

/**
* RSA公钥解密
* @param ciphertext 经BASE64编码过的待解密的密文
* @param pubKey RSA公钥
* @return utf-8编码的明文
*/
public static String pubKeyDec(String ciphertext ,String pubKey){
try {
KeyFactory keyf = KeyFactory.getInstance("RSA","BC");

//获取公钥
InputStream is = new ByteArrayInputStream(pubKey.getBytes("utf-8"));
byte[] pubbytes = new byte[new Long(pubKey.length()).intValue()];
is.read(pubbytes);
X509EncodedKeySpec pubX509 = new X509EncodedKeySpec(Base64.decode(pubbytes,Base64.DEFAULT));
PublicKey pkey = keyf.generatePublic(pubX509);

//公钥解密
Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
cipher.init(Cipher.DECRYPT_MODE, pkey);
byte[] text = cipher.doFinal(Base64.decode(ciphertext,Base64.DEFAULT));

return new String(text,"UTF-8");
} catch (Exception e) {
e.printStackTrace();
throw new RuntimeException(e);
}
}

/**
* RSA私钥加密
* @param content 待加密的明文
* @param privKey RSA私钥
* @return	经BASE64编码后的密文
*/
public static String privKeyEnc(String content,String privKey){
try {
KeyFactory keyf = KeyFactory.getInstance("RSA","BC");

//获取私钥
InputStream key = new ByteArrayInputStream(privKey.getBytes("utf-8"));
byte[] pribytes = new byte[new Long(privKey.length()).intValue()];
key.read(pribytes);
PKCS8EncodedKeySpec priPKCS8 = new PKCS8EncodedKeySpec(Base64.decode(pribytes,Base64.DEFAULT));
PrivateKey prikey = keyf.generatePrivate(priPKCS8);

//私钥加密
Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
cipher.init(Cipher.ENCRYPT_MODE, prikey);
byte[] cipherText = cipher.doFinal(content.getBytes());

//将加密结果转换为Base64编码结果；便于internet传送
return Base64.encodeToString(cipherText,Base64.DEFAULT);
} catch (Exception e) {
e.printStackTrace();
throw new RuntimeException(e);
}
}

/**
* RSA私钥解密
* @param ciphertext	经BASE84编码过的待解密密文
* @param privKey	RSA私钥
* @return	utf-8编码的明文
*/
public static String privKeyDec(String ciphertext ,String privKey){
try {
KeyFactory keyf = KeyFactory.getInstance("RSA","BC");
//          获取私钥
InputStream key = new ByteArrayInputStream(privKey.getBytes("utf-8"));
byte[] pribytes = new byte[new Long(privKey.length()).intValue()];
key.read(pribytes);
byte[] buffer = Base64.decode(pribytes,Base64.DEFAULT);
PKCS8EncodedKeySpec priPKCS8 = new PKCS8EncodedKeySpec(buffer);
PrivateKey prikey = keyf.generatePrivate(priPKCS8);

//私钥解密
Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
cipher.init(Cipher.DECRYPT_MODE, prikey);
byte[] text=Base64.decode(ciphertext,Base64.DEFAULT);
byte[] content = cipher.doFinal(text);
return new String(content,"UTF-8");
} catch (Exception e) {
e.printStackTrace();
throw new RuntimeException(e);
}
}

/**
* RSA私钥数字签名
* @param content 待签内容
* @param privKey RSA私钥
* @return 经BASE64编码后的签名串
*/
public static String sign(String content,String privKey){
try {
KeyFactory keyf=KeyFactory.getInstance("RSA","BC");

//获取私钥
InputStream key = new ByteArrayInputStream(privKey.getBytes("utf-8"));
byte[] pribytes = new byte[new Long(privKey.length()).intValue()];
key.read(pribytes);
PKCS8EncodedKeySpec priPKCS8 = new PKCS8EncodedKeySpec(Base64.decode(new String(pribytes),Base64.DEFAULT));
PrivateKey priKey=keyf.generatePrivate(priPKCS8);

//实例化Signature；签名算法：MD5withRSA
Signature signature = Signature.getInstance("MD5withRSA");
//初始化Signature
signature.initSign(priKey);
//更新
signature.update(content.getBytes());
return Base64.encodeToString(signature.sign(),Base64.DEFAULT);
} catch (Exception e) {
e.printStackTrace();
throw new RuntimeException(e);
}
}

/**
* RSA公钥校验数字签名
* @param content 待校验的内容
* @param pubKey RSA公钥
* @param signedStr 签名字符串
* @return	true:校验成功；false:校验失败
*/
public static boolean verify(String content,String pubKey,String signedStr){
try {
//实例化密钥工厂
KeyFactory keyf=KeyFactory.getInstance("RSA","BC");

//获取公钥
InputStream is = new ByteArrayInputStream(pubKey.getBytes("utf-8"));
byte[] pubbytes = new byte[new Long(pubKey.length()).intValue()];
is.read(pubbytes);
X509EncodedKeySpec pubX509 = new X509EncodedKeySpec(Base64.decode(new String(pubbytes),Base64.DEFAULT));
PublicKey pkey = keyf.generatePublic(pubX509);

//实例化Signature；签名算法：MD5withRSA
Signature signature = Signature.getInstance("MD5withRSA");
signature.initVerify(pkey);
signature.update(content.getBytes());
//验证
return signature.verify(Base64.decode(signedStr,Base64.DEFAULT));
} catch (Exception e) {
e.printStackTrace();
throw new RuntimeException(e);
}
}

}

以上就是AES和RSA的实现。可以直接拿来用的

一般都是这两种配合使用 AES加密先随机生成一个KEY，然后用RSA对称加密，将AES的KEY加密，在用AES对需要加密的文明进行加密。

下面将附加上demo
http://download.csdn.net/detail/sinat_23134455/9502953