From 1976f7d8287319681e435e6000d69e12c69118d5 Mon Sep 17 00:00:00 2001
From: ZhouXY108 <luquanlion@outlook.com>
Date: Wed, 15 Nov 2023 23:02:31 +0800
Subject: [PATCH] =?UTF-8?q?=E5=B0=81=E8=A3=85=20RSA?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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---
 .../zhouxy/plusone/commons/security/RSA.java  | 104 ++++++++++++++++++
 1 file changed, 104 insertions(+)
 create mode 100644 src/main/java/xyz/zhouxy/plusone/commons/security/RSA.java

diff --git a/src/main/java/xyz/zhouxy/plusone/commons/security/RSA.java b/src/main/java/xyz/zhouxy/plusone/commons/security/RSA.java
new file mode 100644
index 0000000..98944da
--- /dev/null
+++ b/src/main/java/xyz/zhouxy/plusone/commons/security/RSA.java
@@ -0,0 +1,104 @@
+package xyz.zhouxy.plusone.commons.security;
+
+import java.nio.charset.StandardCharsets;
+import java.security.InvalidKeyException;
+import java.security.KeyPair;
+import java.security.KeyPairGenerator;
+import java.security.NoSuchAlgorithmException;
+import java.security.PrivateKey;
+import java.security.PublicKey;
+
+import javax.crypto.BadPaddingException;
+import javax.crypto.Cipher;
+import javax.crypto.IllegalBlockSizeException;
+import javax.crypto.NoSuchPaddingException;
+
+import com.google.common.annotations.Beta;
+
+/**
+ * RSA 非对称加密。
+ */
+@Beta
+public class RSA {
+    private static final int DEFAULT_KEY_SIZE = 2048;
+    public static final String NAME = "RSA";
+    private static final String TRANSFORMATION = "RSA/ECB/OAEPWithSHA-256AndMGF1Padding";
+
+    private final PublicKey publicKey;
+    private final PrivateKey privateKey;
+    private final Cipher encryptModeCipher;
+    private final Cipher decryptModeCipher;
+
+    private RSA(final PublicKey publicKey, final PrivateKey privateKey)
+            throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException {
+        this.publicKey = publicKey;
+        this.privateKey = privateKey;
+        this.encryptModeCipher = Cipher.getInstance(TRANSFORMATION);
+        encryptModeCipher.init(Cipher.ENCRYPT_MODE, publicKey);
+        this.decryptModeCipher = Cipher.getInstance(TRANSFORMATION);
+        decryptModeCipher.init(Cipher.DECRYPT_MODE, privateKey);
+    }
+
+    public static RSA of(final PublicKey publicKey, final PrivateKey privateKey) {
+        try {
+            return new RSA(publicKey, privateKey);
+        } catch (NoSuchAlgorithmException | NoSuchPaddingException | InvalidKeyException e) {
+            throw new SecurityException(e);
+        }
+    }
+
+    public static RSA of(final KeyPair keyPair) {
+        try {
+            return new RSA(keyPair.getPublic(), keyPair.getPrivate());
+        } catch (NoSuchAlgorithmException | NoSuchPaddingException | InvalidKeyException e) {
+            throw new SecurityException(e);
+        }
+    }
+
+    public static RSA withKeySize(int keySize) {
+        try {
+            KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance(NAME);
+            keyPairGenerator.initialize(keySize);
+            final KeyPair keyPair = keyPairGenerator.generateKeyPair();
+            return new RSA(keyPair.getPublic(), keyPair.getPrivate());
+        } catch (NoSuchAlgorithmException | NoSuchPaddingException | InvalidKeyException e) {
+            throw new SecurityException(e);
+        }
+    }
+
+    public static RSA withDefaultKeySize() {
+        return withKeySize(DEFAULT_KEY_SIZE);
+    }
+
+    public PrivateKey getPrivateKey() {
+        return privateKey;
+    }
+
+    public PublicKey getPublicKey() {
+        return publicKey;
+    }
+
+    public byte[] encrypt(byte[] input) throws IllegalBlockSizeException, BadPaddingException {
+        return encryptModeCipher.doFinal(input);
+    }
+
+    public byte[] encrypt(String input) throws IllegalBlockSizeException, BadPaddingException {
+        return encrypt(input.getBytes(StandardCharsets.UTF_8));
+    }
+
+    public String encryptToString(String input) throws IllegalBlockSizeException, BadPaddingException {
+        return new String(encrypt(input));
+    }
+
+    public byte[] decrypt(byte[] input) throws IllegalBlockSizeException, BadPaddingException {
+        return decryptModeCipher.doFinal(input);
+    }
+
+    public byte[] decrypt(String input) throws IllegalBlockSizeException, BadPaddingException {
+        return decryptModeCipher.doFinal(input.getBytes(StandardCharsets.UTF_8));
+    }
+
+    public String decryptToString(String input) throws IllegalBlockSizeException, BadPaddingException {
+        return new String(decrypt(input));
+    }
+}