feat: add VerifyRequest to check if request signed by qn

Author: lihsai0

src/Qiniu/Util/Signature.cs

@@ -200,5 +200,50 @@ public string SignRequestV2(string method, string url, StringDictionary headers,
         {
             return SignRequestV2(method, url, headers, Encoding.UTF8.GetString(body));
         }
+
+        public bool VerifyRequest(
+            string method,
+            string url,
+            StringDictionary headers,
+            string body = null
+        )
+        {
+            byte[] bodyBytes = null;
+            if (!string.IsNullOrEmpty(body)) {
+                bodyBytes = Encoding.UTF8.GetBytes(body);
+            }
+            return VerifyRequest(
+                method,
+                url,
+                headers,
+                bodyBytes
+            );
+        }
+
+        public bool VerifyRequest(
+            string method,
+            string url,
+            StringDictionary headers,
+            byte[] body = null
+        )
+        {
+            if (!headers.ContainsKey("Authorization"))
+            {
+                return false;
+            }
+
+            string authString = headers["Authorization"];
+            if (authString.StartsWith("QBox "))
+            {
+                return authString == "QBox " + SignRequest(url, body);
+            }
+
+            if (authString.StartsWith("Qiniu "))
+            {
+                return authString == "Qiniu " + SignRequestV2(method, url, headers, body);
+            }
+
+            return false;
+        }
     }
 }

src/QiniuTests/Util/Signature.cs

@@ -23,5 +23,13 @@ public string SignatureV2ByBytesTest(string method, string url, StringDictionary
         {
             return string.Format("Qiniu {0}", sign.SignRequestV2(method, url, headers, Encoding.UTF8.GetBytes(body)));
         }
+
+        [TestCaseSource(typeof(VerifyRequestDataClass), nameof(VerifyRequestDataClass.TestCases))]
+        public bool VerifyRequestTest(string method, string url, StringDictionary headers, string body)
+        {
+            Mac mac = new Mac("abcdefghklmnopq", "1234567890");
+            Signature mockSign = new Signature(mac);
+            return mockSign.VerifyRequest(method, url, headers, body);
+        }
     }
 }

src/QiniuTests/Util/TestCases.cs

@@ -211,4 +211,36 @@ public static IEnumerable TestCases
             }
         }
     }
-}
+
+    public class VerifyRequestDataClass
+    {
+        public static IEnumerable TestCases
+        {
+            get
+            {
+                yield return new TestCaseData(
+                    "",
+                    "https://test.qiniu.com/callback",
+                    new StringDictionary
+                    {
+                        {"Authorization", "QBox abcdefghklmnopq:T7F-SjxX7X2zI4Fc1vANiNt1AUE="},
+                        {"Content-Type", "application/x-www-form-urlencoded"}
+                    },
+                    "name=sunflower.jpg&hash=Fn6qeQi4VDLQ347NiRm-RlQx_4O2&location=Shanghai&price=1500.00&uid=123"
+                ).Returns(true);
+
+                yield return new TestCaseData(
+                    "GET",
+                    "https://test.qiniu.com/callback",
+                    new StringDictionary
+                    {
+                        {"Authorization", "Qiniu abcdefghklmnopq:ZqS7EZuAKrhZaEIxqNGxDJi41IQ="},
+                        {"X-Qiniu-Bbb", "BBB"},
+                        {"Content-Type", "application/x-www-form-urlencoded"}
+                    },
+                    "name=sunflower.jpg&hash=Fn6qeQi4VDLQ347NiRm-RlQx_4O2&location=Shanghai&price=1500.00&uid=123"
+                ).Returns(true);
+            }
+        }
+    }
+}