From 214d1d01da3a59fe6f052ff727143fc6cfbf876f Mon Sep 17 00:00:00 2001
From: dimengzhe <dimengzhe>
Date: Sat, 7 Dec 2024 16:17:30 +0800
Subject: [PATCH] =?UTF-8?q?=E5=AF=B9=E5=A4=96?=
MIME-Version: 1.0
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---
 src/main/java/SignatureUtil.java      | 71 +++++++++++++++++++++++++++
 src/main/java/SignatureValidator.java | 28 +++++++++++
 2 files changed, 99 insertions(+)
 create mode 100644 src/main/java/SignatureUtil.java
 create mode 100644 src/main/java/SignatureValidator.java

diff --git a/src/main/java/SignatureUtil.java b/src/main/java/SignatureUtil.java
new file mode 100644
index 0000000..eb7ef45
--- /dev/null
+++ b/src/main/java/SignatureUtil.java
@@ -0,0 +1,71 @@
+import java.io.UnsupportedEncodingException;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.util.Map;
+import java.util.TreeMap;
+
+/**
+ * @description: 生成签名
+ * @author: dimengzhe
+ * @date: 2024/11/28
+ **/
+public class SignatureUtil {
+
+
+    /**
+     * 生成请求签名
+     *
+     * @param parameters 请求参数
+     * @param appKey     应用的 AppKey
+     * @param secret     密钥
+     * @return 签名
+     */
+    public static String generateSignature(Map<String, String> parameters, String appKey, String secret) throws UnsupportedEncodingException, NoSuchAlgorithmException {
+        // 1. 使用 TreeMap 按照字典顺序对参数进行排序
+        Map<String, String> sortedParams = new TreeMap<>(parameters);
+        sortedParams.put("_app", appKey); // 添加应用的 AppKey
+        sortedParams.put("_t", String.valueOf(System.currentTimeMillis())); // 添加时间戳
+
+        // 2. 拼接参数字符串
+        String content = joinParameters(sortedParams);
+
+        // 3. 将密钥加在参数字符串的前后
+        content = secret + content + secret;
+
+        // 4. 计算签名 (MD5)
+        return md5(content);
+    }
+
+    /**
+     * 拼接参数字符串
+     *
+     * @param parameters 排序后的参数
+     * @return 拼接后的参数字符串
+     */
+    private static String joinParameters(Map<String, String> parameters) throws UnsupportedEncodingException {
+        StringBuilder builder = new StringBuilder();
+        for (Map.Entry<String, String> entry : parameters.entrySet()) {
+            if (builder.length() > 0) {
+                builder.append("&");
+            }
+            builder.append(entry.getKey()).append("=").append(entry.getValue());
+        }
+        return builder.toString();
+    }
+
+    /**
+     * 计算 MD5
+     *
+     * @param content 要计算 MD5 的字符串
+     * @return MD5 值
+     */
+    private static String md5(String content) throws NoSuchAlgorithmException {
+        MessageDigest md = MessageDigest.getInstance("MD5");
+        byte[] bytes = md.digest(content.getBytes());
+        StringBuilder sb = new StringBuilder();
+        for (byte b : bytes) {
+            sb.append(String.format("%02x", b));
+        }
+        return sb.toString();
+    }
+}
diff --git a/src/main/java/SignatureValidator.java b/src/main/java/SignatureValidator.java
new file mode 100644
index 0000000..43a2052
--- /dev/null
+++ b/src/main/java/SignatureValidator.java
@@ -0,0 +1,28 @@
+import java.io.UnsupportedEncodingException;
+import java.security.NoSuchAlgorithmException;
+import java.util.Map;
+
+/**
+ * @description: 验证签名方法
+ * @author: dimengzhe
+ * @date: 2024/11/28
+ **/
+public class SignatureValidator {
+
+    /**
+     * 验证签名是否正确
+     *
+     * @param parameters        请求参数
+     * @param appKey            应用的 AppKey
+     * @param secret            密钥
+     * @param receivedSignature 请求中的签名
+     * @return 是否验证通过
+     */
+    public static boolean validateSignature(Map<String, String> parameters, String appKey, String secret, String receivedSignature) throws UnsupportedEncodingException, NoSuchAlgorithmException {
+        // 1. 重新生成签名
+        String calculatedSignature = SignatureUtil.generateSignature(parameters, appKey, secret);
+
+        // 2. 比较计算出来的签名和请求中的签名
+        return calculatedSignature.equals(receivedSignature);
+    }
+}