From f72f6dea7898c67f529fd7976e3313916f0a8ac2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E9=99=88=E5=9B=BD=E4=BC=9F?= <366193849@qq.com>
Date: Mon, 27 Sep 2021 17:46:06 +0800
Subject: [PATCH] =?UTF-8?q?=E6=81=A2=E5=A4=8DEdns?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 FastGithub.DomainResolve/DnscryptProxy.cs |  2 ++
 FastGithub.DomainResolve/TomlUtil.cs      | 43 ++++++++++++++++++++++-
 2 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/FastGithub.DomainResolve/DnscryptProxy.cs b/FastGithub.DomainResolve/DnscryptProxy.cs
index 7fc15da..7905e0d 100644
--- a/FastGithub.DomainResolve/DnscryptProxy.cs
+++ b/FastGithub.DomainResolve/DnscryptProxy.cs
@@ -40,7 +40,9 @@ namespace FastGithub.DomainResolve
             var tomlPath = Path.Combine(PATH, $"{NAME}.toml");
             var port = GetAvailablePort(IPAddress.Loopback.AddressFamily);
             var localEndPoint = new IPEndPoint(IPAddress.Loopback, port);
+
             await TomlUtil.SetListensAsync(tomlPath, localEndPoint, cancellationToken);
+            await TomlUtil.SetEdnsClientSubnetAsync(tomlPath, cancellationToken);
 
             foreach (var process in Process.GetProcessesByName(NAME))
             {
diff --git a/FastGithub.DomainResolve/TomlUtil.cs b/FastGithub.DomainResolve/TomlUtil.cs
index 2b73381..148c4d1 100644
--- a/FastGithub.DomainResolve/TomlUtil.cs
+++ b/FastGithub.DomainResolve/TomlUtil.cs
@@ -1,6 +1,9 @@
-using System.IO;
+using System;
+using System.IO;
 using System.Net;
+using System.Net.Http;
 using System.Text;
+using System.Text.RegularExpressions;
 using System.Threading;
 using System.Threading.Tasks;
 using Tommy;
@@ -27,6 +30,44 @@ namespace FastGithub.DomainResolve
             return SetAsync(tomlPath, "listen_addresses", value, cancellationToken);
         }
 
+        /// <summary>
+        /// 设置ecs
+        /// </summary>
+        /// <param name="tomlPath"></param> 
+        /// <param name="cancellationToken"></param>
+        /// <returns></returns>
+        public static async Task<bool> SetEdnsClientSubnetAsync(string tomlPath, CancellationToken cancellationToken = default)
+        {
+            try
+            {
+                var address = await GetPublicIPAddressAsync(cancellationToken);
+                if (address != null)
+                {
+                    var value = new TomlArray { $"{address}/32" };
+                    await SetAsync(tomlPath, "edns_client_subnet", value, cancellationToken);
+                }
+                return true;
+            }
+            catch (Exception)
+            {
+                return false;
+            }
+        }
+
+        /// <summary>
+        /// 获取公网ip
+        /// </summary>
+        /// <param name="cancellationToken"></param>
+        /// <returns></returns>
+        private static async Task<IPAddress?> GetPublicIPAddressAsync(CancellationToken cancellationToken)
+        {
+            using var httpClient = new HttpClient { Timeout = TimeSpan.FromSeconds(3d) };
+            var response = await httpClient.GetStringAsync("https://pv.sohu.com/cityjson?ie=utf-8", cancellationToken);
+            var match = Regex.Match(response, @"\d+\.\d+\.\d+\.\d+");
+            IPAddress.TryParse(match.Value, out var address);
+            return address;
+        }
+
         /// <summary>
         /// 设置指定键的值
         /// </summary>