Java笔记-非对称加密RSA的使用

小鱼儿 2022-09-05 04:20 93阅读 0赞

使用OpenSSL生成对应RSA私钥和RSA公钥：

#rsa私钥：
    genrsa -out rsa_private_key.pem 1024
    pkcs8 -topk8 -inform PEM -in rsa_private_key.pem -outform pem -nocrypt -out rsa_private_key_8.pem
    #rsa公钥：
    rsa -in rsa_private_key_8.pem -pubout -out rsa_public_key.pem

Base64使用的是这样Maven

<dependency>
        <groupId>commons-codec</groupId>
        <artifactId>commons-codec</artifactId>
        <version>1.11</version>
    </dependency>

这里生成的公钥和私钥是Base64的，如下：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxNzg0NDI3NjE_size_16_color_FFFFFF_t_70][]

公钥：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxNzg0NDI3NjE_size_16_color_FFFFFF_t_70 1][]

所以用的时候需要先用base64解密。

使用逻辑是这样的，先那这些密钥进行Base64解密。

在用公钥给内容加密，用私钥解密：

Base64相关的代码：

DataSecret.java

package cn.it1995.tool;
    
    import org.apache.commons.codec.binary.Base64;
    
    import java.io.UnsupportedEncodingException;
    
    public class DataSecret {
    
    
        public static byte[] encode(byte[] txt) throws UnsupportedEncodingException {
    
            return Base64.encodeBase64(txt);
        }
    
        public static byte[] decode(String txt){
    
            return Base64.decodeBase64(txt);
        }
    }

RSA.java

package cn.it1995.tool;
    
    import javax.crypto.BadPaddingException;
    import javax.crypto.Cipher;
    import javax.crypto.IllegalBlockSizeException;
    import javax.crypto.NoSuchPaddingException;
    import java.io.UnsupportedEncodingException;
    import java.security.InvalidKeyException;
    import java.security.KeyFactory;
    import java.security.NoSuchAlgorithmException;
    import java.security.interfaces.RSAPrivateCrtKey;
    import java.security.interfaces.RSAPublicKey;
    import java.security.spec.InvalidKeySpecException;
    import java.security.spec.PKCS8EncodedKeySpec;
    import java.security.spec.X509EncodedKeySpec;
    
    public class RSA {
    
        private static final String RSA_ALGORITHM = "RSA/ECB/PKCS1Padding";
    
        //加密回的是base64
        public static String encrypt(String data, String key) throws UnsupportedEncodingException {
    
            String message = data;
            byte[] decode = DataSecret.decode(key);
            byte[] result = new byte[]{0};
    
            try {
    
                RSAPublicKey publicKey = (RSAPublicKey) KeyFactory.getInstance("RSA")
                        .generatePublic(new X509EncodedKeySpec(decode));
                Cipher cipher = Cipher.getInstance(RSA_ALGORITHM);
                cipher.init(Cipher.ENCRYPT_MODE, publicKey);
                result = cipher.doFinal(message.getBytes("UTF-8"));
            }
            catch (NoSuchAlgorithmException e) {
    
                e.printStackTrace();
            }
            catch (InvalidKeySpecException e) {
    
                e.printStackTrace();
            }
            catch (NoSuchPaddingException e) {
    
                e.printStackTrace();
            }
            catch (BadPaddingException e) {
    
                e.printStackTrace();
            }
            catch (IllegalBlockSizeException e) {
    
                e.printStackTrace();
            }
            catch (InvalidKeyException e) {
    
                e.printStackTrace();
            }
    
            return new String(DataSecret.encode(result));
        }
    
        //解密
        public static String decrypt(String encrypted, String key){
    
            byte[] content = DataSecret.decode(encrypted);
            byte[] decoded = DataSecret.decode(key);
    
            byte[] result = new byte[]{0};
    
            try {
    
                RSAPrivateCrtKey priKey = (RSAPrivateCrtKey)KeyFactory.getInstance("RSA")
                        .generatePrivate(new PKCS8EncodedKeySpec(decoded));
                Cipher cipher = Cipher.getInstance(RSA_ALGORITHM);
                cipher.init(Cipher.DECRYPT_MODE, priKey);
                result = cipher.doFinal(content);
            }
            catch (InvalidKeySpecException e){
    
                e.printStackTrace();
            }
            catch (NoSuchAlgorithmException e) {
    
                e.printStackTrace();
            }
            catch (NoSuchPaddingException e) {
    
                e.printStackTrace();
            }
            catch (InvalidKeyException e) {
    
                e.printStackTrace();
            }
            catch (BadPaddingException e) {
    
                e.printStackTrace();
            }
            catch (IllegalBlockSizeException e) {
    
                e.printStackTrace();
            }
    
            return new String(result);
        }
    }

调用代码：

private static final String PUB_KEY = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCjuN97tkBc0QcKGU9oXydaQN7q" +
                "wZnThxTOmdIc8O1yuA9FrDZpZ3Sz908vTqM/YPZkOUaYrGwsBO7FeQovoX7nQPKu" +
                "YQpRDqt7OKzhwPavyynH0Jz38PDyCBw45zwl4Ux8BtsggTrGVxAqNjO4KkuyL1QS" +
                "8amn4Fzl1CBre8Y0gQIDAQAB";
    
        private static final String PRI_KEY = "MIICdAIBADANBgkqhkiG9w0BAQEFAASCAl4wggJaAgEAAoGBAKO433u2QFzRBwoZ" +
                "T2hfJ1pA3urBmdOHFM6Z0hzw7XK4D0WsNmlndLP3Ty9Ooz9g9mQ5RpisbCwE7sV5" +
                "Ci+hfudA8q5hClEOq3s4rOHA9q/LKcfQnPfw8PIIHDjnPCXhTHwG2yCBOsZXECo2" +
                "M7gqS7IvVBLxqafgXOXUIGt7xjSBAgMBAAECgYAgp0uzcdsOaAY+ZmPnDitcHdoX" +
                "+jsC7EsjFZzJduf03G73V2yWwzKMfkPFzKpUhrM9tAq3gpQkh2tT6Vs1usEDbrDd" +
                "e08Cc3D5YWK7HuTfO3kkJTSNOK0JfuT1UQaTjCmDQWWjPmYbu6UN0UDv4Mo26dgl" +
                "cp9h0wlaPsSFN3O97QJBANgj+4i7ABAdbTuUfq6Tcr38E7wYSFTUeL5jTd4sO636" +
                "+KJ6zx4uTXAmxnt9OdIY1ihLRqDh8VbiorqOelGf6iMCQQDB6jZver3mTMe6ntSY" +
                "hx3JWOCDM3ULkPvOWGrAcRsNKjyIuo37taXa7fuqmVQQq9MJYikJfilMhkgwkV/X" +
                "ihcLAkBsOvBskj9A0ottJzmcT4dIbR6wtHQbzl078NwAIaQsxZyVN+vY0BTE0RXY" +
                "pmc6tmcevDr8uscv28Liqg/EKdCDAkAjL9C44djblUsYvgFtu/bXtlzm8ctnUeOf" +
                "ScP1L5DtDqD1XoStDAUQeOaVykTK0aL1rO4tXss3q5Yl2fs+LTyJAj8f7N5kzw08" +
                "9S5OWCHoEm5UOeAvjFh//cjXi6lyqetBW3w17muZ2OumUAbKJXksyzmT6/QRpkX3" +
                "S0w/tqdJXLs=";
    
        public static void main(String[] args) throws UnsupportedEncodingException {
    
            String content = "123456";
            String encrypted = RSA.encrypt(content, PUB_KEY);
            System.out.println(encrypted);
            System.out.println(RSA.decrypt(encrypted, PRI_KEY));
            ......
            ......
       }

运行截图如下：

![20210817085210397.png][]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxNzg0NDI3NjE_size_16_color_FFFFFF_t_70]: /images/20220829/c9cf71a02cef4ad49613eb47fc90f232.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxNzg0NDI3NjE_size_16_color_FFFFFF_t_70 1]: /images/20220829/922de99b94154c5b9a1d8868134caefd.png
[20210817085210397.png]: /images/20220829/42154c76d5f640de9ea02d94bd02f31f.png