From e88f6b43ad056c0a72ff1309bcaec1cdf83f7269 Mon Sep 17 00:00:00 2001
From: wh <wanghao@qq.com>
Date: Sun, 10 May 2026 22:04:52 +0800
Subject: [PATCH] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=E5=9B=BD=E5=AF=86sm4?=
 =?UTF-8?q?=E5=8A=A0=E8=A7=A3=E5=AF=86?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 pom.xml                                       |   7 +-
 .../com/labelsys/backend/util/SM4Util.java    | 104 ++++++++++++++++++
 2 files changed, 110 insertions(+), 1 deletion(-)
 create mode 100644 src/main/java/com/labelsys/backend/util/SM4Util.java

diff --git a/pom.xml b/pom.xml
index ad3696d..e02f2c1 100644
--- a/pom.xml
+++ b/pom.xml
@@ -84,6 +84,11 @@
             <artifactId>lombok</artifactId>
             <optional>true</optional>
         </dependency>
+        <dependency>
+            <groupId>org.bouncycastle</groupId>
+            <artifactId>bcprov-jdk18on</artifactId>
+            <version>1.78.1</version>
+        </dependency>
         <dependency>
             <groupId>software.amazon.awssdk</groupId>
             <artifactId>s3</artifactId>
@@ -137,4 +142,4 @@
             </plugin>
         </plugins>
     </build>
-</project>
+</project>
\ No newline at end of file
diff --git a/src/main/java/com/labelsys/backend/util/SM4Util.java b/src/main/java/com/labelsys/backend/util/SM4Util.java
new file mode 100644
index 0000000..1c6d144
--- /dev/null
+++ b/src/main/java/com/labelsys/backend/util/SM4Util.java
@@ -0,0 +1,104 @@
+package com.labelsys.backend.util;
+
+import org.bouncycastle.crypto.engines.SM4Engine;
+import org.bouncycastle.crypto.modes.CBCBlockCipher;
+import org.bouncycastle.crypto.paddings.PaddedBufferedBlockCipher;
+import org.bouncycastle.crypto.params.KeyParameter;
+import org.bouncycastle.crypto.params.ParametersWithIV;
+
+import java.nio.charset.StandardCharsets;
+import java.util.Base64;
+
+public class SM4Util {
+
+    private static final int KEY_LENGTH = 16;
+    private static final int IV_LENGTH  = 16;
+
+    public static String encrypt(String plainText, String key, String iv) {
+        try {
+            validateKey(key);
+            validateIV(iv);
+
+            byte[] keyBytes = key.getBytes(StandardCharsets.UTF_8);
+            byte[] ivBytes = iv.getBytes(StandardCharsets.UTF_8);
+            byte[] plainBytes = plainText.getBytes(StandardCharsets.UTF_8);
+
+            SM4Engine engine = new SM4Engine();
+            CBCBlockCipher blockCipher = new CBCBlockCipher(engine);
+            PaddedBufferedBlockCipher cipher = new PaddedBufferedBlockCipher(blockCipher);
+
+            KeyParameter keyParameter = new KeyParameter(keyBytes);
+            ParametersWithIV parametersWithIV = new ParametersWithIV(keyParameter, ivBytes);
+            cipher.init(true, parametersWithIV);
+
+            byte[] encrypted = new byte[cipher.getOutputSize(plainBytes.length)];
+            int len = cipher.processBytes(plainBytes, 0, plainBytes.length, encrypted, 0);
+            len += cipher.doFinal(encrypted, len);
+
+            return Base64.getEncoder().encodeToString(encrypted);
+        } catch (Exception e) {
+            throw new RuntimeException("SM4加密失败", e);
+        }
+    }
+
+    public static String decrypt(String cipherText, String key, String iv) {
+        try {
+            validateKey(key);
+            validateIV(iv);
+
+            byte[] keyBytes = key.getBytes(StandardCharsets.UTF_8);
+            byte[] ivBytes = iv.getBytes(StandardCharsets.UTF_8);
+            byte[] cipherBytes = Base64.getDecoder().decode(cipherText);
+
+            SM4Engine engine = new SM4Engine();
+            CBCBlockCipher blockCipher = new CBCBlockCipher(engine);
+            PaddedBufferedBlockCipher cipher = new PaddedBufferedBlockCipher(blockCipher);
+
+            KeyParameter keyParameter = new KeyParameter(keyBytes);
+            ParametersWithIV parametersWithIV = new ParametersWithIV(keyParameter, ivBytes);
+            cipher.init(false, parametersWithIV);
+
+            byte[] decrypted = new byte[cipher.getOutputSize(cipherBytes.length)];
+            int len = cipher.processBytes(cipherBytes, 0, cipherBytes.length, decrypted, 0);
+            len += cipher.doFinal(decrypted, len);
+
+            return new String(decrypted, 0, len, StandardCharsets.UTF_8);
+        } catch (Exception e) {
+            throw new RuntimeException("SM4解密失败", e);
+        }
+    }
+
+    public static String encrypt(String plainText, String key) {
+        return encrypt(plainText, key, key.substring(0, IV_LENGTH));
+    }
+
+    public static String decrypt(String cipherText, String key) {
+        return decrypt(cipherText, key, key.substring(0, IV_LENGTH));
+    }
+
+    private static void validateKey(String key) {
+        if (key == null || key.length() != KEY_LENGTH) {
+            throw new IllegalArgumentException("SM4密钥长度必须为16位");
+        }
+    }
+
+    private static void validateIV(String iv) {
+        if (iv == null || iv.length() != IV_LENGTH) {
+            throw new IllegalArgumentException("SM4 IV长度必须为16位");
+        }
+    }
+
+    static void main() {
+        String key = "1234567890123456";
+        String iv = "abcdefghijklmnop";
+
+        String plainText = "Hello World!";
+
+        String encrypted = SM4Util.encrypt(plainText, key, iv);
+        String decrypted = SM4Util.decrypt(encrypted, key, iv);
+
+        System.out.println("原文: " + plainText);
+        System.out.println("密文: " + encrypted);
+        System.out.println("解密: " + decrypted);
+    }
+}
\ No newline at end of file