Profile pre-resolver (#10220)

* Profile pre-resolver

* Try cname

* UI

v2rayN/ServiceLib/Global.cs

@@ -499,6 +499,20 @@ public class Global
         "localhost"
     ];
 
+    public static readonly List<string> DomainDNS4PreResolveAddress =
+    [
+        "",
+        "https://doh.pub/dns-query",
+        "https://dns.alidns.com/dns-query",
+        "119.29.29.29",
+        "223.5.5.5",
+        "localhost",
+        "https://cloudflare-dns.com/dns-query",
+        "https://dns.google/dns-query",
+        "8.8.8.8",
+        "1.1.1.1",
+    ];
+
     public static readonly List<LanguageOption> LanguageOptions =
     [
         new("zh-Hans", "简体中文"),

v2rayN/ServiceLib/Handler/ConfigHandler.cs

@@ -1713,11 +1713,16 @@ public static class ConfigHandler
         }
 
         var subFilter = string.Empty;
+        var preResolver = string.Empty;
         if (isSub && subid.IsNotEmpty())
         {
             subFilter = (await AppManager.Instance.GetSubItem(subid))?.Filter ?? "";
+            preResolver = (await AppManager.Instance.GetSubItem(subid))?.PreResolver ?? "";
         }
 
+        var dnsClient = preResolver.IsNullOrEmpty() ? null : EndpointResolveManager.BuildDnsClient(preResolver);
+        var dnsCache = new Dictionary<string, string>();
+
         var countServers = 0;
         List<ProfileItem> lstAdd = [];
         var arrData = strData.Split(Environment.NewLine.ToCharArray()).Where(t => !t.IsNullOrEmpty());
@@ -1753,6 +1758,21 @@ public static class ConfigHandler
             profileItem.Subid = subid;
             profileItem.IsSub = isSub;
 
+            if (dnsClient is not null && profileItem.Address.IsNotEmpty())
+            {
+                if (!dnsCache.TryGetValue(profileItem.Address, out var resolvedAddress))
+                {
+                    var ipList = await dnsClient.ResolveIpv46Async(profileItem.Address);
+                    resolvedAddress = ipList.FirstOrDefault()?.ToString() ?? profileItem.Address;
+                    dnsCache[profileItem.Address] = resolvedAddress;
+                }
+                if (!resolvedAddress.IsNullOrEmpty())
+                {
+                    profileItem.Address = resolvedAddress;
+                }
+                // TODO: Override the host and sni if empty
+            }
+
             var addStatus = profileItem.ConfigType switch
             {
                 EConfigType.VMess => await AddVMessServer(config, profileItem, false),
@@ -2297,6 +2317,7 @@ public static class ConfigHandler
             item.PreSocksPort = subItem.PreSocksPort;
             item.Memo = subItem.Memo;
             item.CustomCoreType = subItem.CustomCoreType;
+            item.PreResolver = subItem.PreResolver;
         }
 
         if (item.Id.IsNullOrEmpty())

v2rayN/ServiceLib/Manager/EndpointResolveManager.cs

@@ -0,0 +1,523 @@
+using System.Net.Http.Headers;
+
+namespace ServiceLib.Manager;
+
+public class EndpointResolveManager
+{
+    public static IDnsResolver BuildDnsClient(string dnsServer)
+    {
+        if (string.IsNullOrEmpty(dnsServer))
+        {
+            throw new ArgumentNullException(nameof(dnsServer));
+        }
+
+        if (dnsServer is "local" or "localhost" or "system" or "dhcp" ||
+            dnsServer.StartsWith("127.0.0.1") ||
+            dnsServer.StartsWith("::1"))
+        {
+            return new SystemDnsResolver();
+        }
+
+        var (domain, scheme, port, path) = Utils.ParseUrl(dnsServer);
+
+        if (string.IsNullOrEmpty(scheme))
+        {
+            return new UdpDnsResolver(new IPEndPoint(IPAddress.Parse(domain), 53));
+        }
+
+        var processedScheme = scheme.ToLowerInvariant().Replace("+local", "");
+
+        switch (processedScheme)
+        {
+            case "udp":
+                return new UdpDnsResolver(new IPEndPoint(IPAddress.Parse(domain), port != 0 ? port : 53));
+
+            case "tcp":
+                return new TcpDnsResolver(new IPEndPoint(IPAddress.Parse(domain), port != 0 ? port : 53));
+
+            case "doh" or "https":
+                {
+                    var uri = new Uri($"https://{domain}:{(port != 0 ? port : 443)}{path}");
+                    var httpClient = new HttpClient();
+                    return new DohDnsResolver(httpClient, uri);
+                }
+
+            default:
+                throw new NotSupportedException($"Unsupported DNS scheme: {scheme}");
+        }
+    }
+
+    public class DnsWire
+    {
+        #region Build DNS Query
+
+        public static byte[] BuildQuery(string host, ushort queryType)
+        {
+            if (queryType is not (1 or 28))
+            {
+                throw new ArgumentOutOfRangeException(nameof(queryType));
+            }
+
+            if (string.IsNullOrWhiteSpace(host))
+            {
+                throw new ArgumentException("Host is empty.", nameof(host));
+            }
+
+            host = host.TrimEnd('.');
+
+            if (host.Length == 0)
+            {
+                host = ".";
+            }
+
+            using var stream = new MemoryStream();
+
+            // Header
+            WriteUInt16(stream, 0);
+            WriteUInt16(stream, 0x0100);
+            WriteUInt16(stream, 1);
+            WriteUInt16(stream, 0);
+            WriteUInt16(stream, 0);
+            WriteUInt16(stream, 0);
+
+            // Question: QNAME
+            if (host != ".")
+            {
+                var labels = host.Split('.');
+                foreach (var label in labels)
+                {
+                    if (label.Length is < 1 or > 63)
+                    {
+                        throw new ArgumentException($"Invalid DNS label length: {label.Length}.", nameof(host));
+                    }
+
+                    foreach (var c in label)
+                    {
+                        if (c > 0x7F)
+                        {
+                            throw new ArgumentException("Non-ASCII domain names must be converted to A-labels first.",
+                                nameof(host));
+                        }
+                    }
+
+                    stream.WriteByte((byte)label.Length);
+
+                    var labelBytes = Encoding.ASCII.GetBytes(label);
+                    stream.Write(labelBytes, 0, labelBytes.Length);
+                }
+            }
+
+            stream.WriteByte(0);
+
+            // Question: QTYPE & QCLASS
+            WriteUInt16(stream, queryType);
+            WriteUInt16(stream, 1);
+
+            return stream.ToArray();
+        }
+
+        private static void WriteUInt16(Stream stream, ushort value)
+        {
+            stream.WriteByte((byte)(value >> 8));
+            stream.WriteByte((byte)(value & 0xFF));
+        }
+
+        #endregion
+
+        #region Parse DNS Response
+
+        public static List<IPAddress> ParseAddresses(
+            ReadOnlySpan<byte> message,
+            ushort expectedType)
+        {
+            return ParseResponse(message, expectedType).Addresses;
+        }
+
+        public static DnsResponse ParseResponse(
+            ReadOnlySpan<byte> message,
+            ushort expectedType)
+        {
+            if (expectedType is not (1 or 28))
+            {
+                throw new ArgumentOutOfRangeException(nameof(expectedType));
+            }
+
+            if (message.Length < 12)
+            {
+                throw new InvalidDataException("DNS message is too short.");
+            }
+
+            var flags = ReadUInt16(message, 2);
+            var questionCount = ReadUInt16(message, 4);
+            var answerCount = ReadUInt16(message, 6);
+
+            // QR = 1
+            if ((flags & 0x8000) == 0)
+            {
+                throw new InvalidDataException("Not a DNS response.");
+            }
+
+            // RCODE
+            var rcode = flags & 0x000F;
+            if (rcode != 0)
+            {
+                return new DnsResponse([], null);
+            }
+
+            var offset = 12;
+
+            // Parse the Question section to obtain the query name.
+            string? queryName = null;
+            for (var i = 0; i < questionCount; i++)
+            {
+                var name = ReadName(message, offset, out offset);
+                queryName ??= NormalizeName(name);
+
+                if (offset + 4 > message.Length)
+                {
+                    throw new InvalidDataException("Invalid DNS question.");
+                }
+
+                offset += 4; // QTYPE + QCLASS
+            }
+
+            var addresses = new List<IPAddress>();
+            string? cname = null;
+
+            for (var i = 0; i < answerCount; i++)
+            {
+                // NAME
+                var ownerName = ReadName(message, offset, out offset);
+
+                if (offset + 10 > message.Length)
+                {
+                    throw new InvalidDataException("Invalid DNS answer.");
+                }
+
+                var type = ReadUInt16(message, offset);
+                var @class = ReadUInt16(message, offset + 2);
+                // TTL
+                var rdLength = ReadUInt16(message, offset + 8);
+
+                offset += 10;
+
+                if (offset + rdLength > message.Length)
+                {
+                    throw new InvalidDataException("Invalid DNS RDATA.");
+                }
+
+                if (@class != 1)
+                {
+                    offset += rdLength;
+                    continue;
+                }
+
+                var ownerMatchesQuery = NamesEqual(ownerName, queryName);
+                var ownerMatchesCname = NamesEqual(ownerName, cname);
+
+                if (type == expectedType)
+                {
+                    if (ownerMatchesQuery || ownerMatchesCname)
+                    {
+                        if (expectedType == 1 && rdLength == 4)
+                        {
+                            addresses.Add(new IPAddress(
+                                message.Slice(offset, 4)));
+                        }
+                        else if (expectedType == 28 && rdLength == 16)
+                        {
+                            addresses.Add(new IPAddress(
+                                message.Slice(offset, 16)));
+                        }
+                    }
+                }
+                else if (type == 5 && ownerMatchesQuery && cname is null)
+                {
+                    cname = ReadName(message, offset, out _);
+                }
+
+                offset += rdLength;
+            }
+
+            return new DnsResponse(addresses, cname);
+        }
+
+        public static async Task<List<IPAddress>> ResolveWithCnameAsync(
+            string host,
+            bool ipv6,
+            Func<string, ushort, CancellationToken, Task<byte[]>> queryAsync,
+            CancellationToken cancellationToken = default)
+        {
+            if (string.IsNullOrWhiteSpace(host))
+            {
+                throw new ArgumentException("Host is empty.", nameof(host));
+            }
+
+            var queryType = ipv6 ? (ushort)28 : (ushort)1;
+            var currentName = host.TrimEnd('.');
+            var visited = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
+            const int maxHops = 8;
+
+            for (var hop = 0; hop < maxHops; hop++)
+            {
+                if (!visited.Add(currentName))
+                {
+                    // CNAME loop detected.
+                    return [];
+                }
+
+                var response = await queryAsync(currentName, queryType, cancellationToken);
+                var result = ParseResponse(response, queryType);
+
+                if (result.Addresses.Count > 0)
+                {
+                    return result.Addresses;
+                }
+
+                if (string.IsNullOrWhiteSpace(result.Cname))
+                {
+                    return [];
+                }
+
+                currentName = result.Cname.TrimEnd('.');
+            }
+
+            return [];
+        }
+
+        public static string ReadName(
+            ReadOnlySpan<byte> message,
+            int offset,
+            out int nextOffset)
+        {
+            var name = new StringBuilder();
+            var position = offset;
+            var endOffset = -1;
+            var pointerCount = 0;
+
+            while (true)
+            {
+                if ((uint)position >= (uint)message.Length)
+                {
+                    throw new InvalidDataException("Invalid DNS name.");
+                }
+
+                var length = message[position];
+
+                // End of name.
+                if (length == 0)
+                {
+                    position++;
+                    if (endOffset < 0)
+                    {
+                        endOffset = position;
+                    }
+                    break;
+                }
+
+                // Compression pointer.
+                if ((length & 0xC0) == 0xC0)
+                {
+                    if (position + 1 >= message.Length)
+                    {
+                        throw new InvalidDataException("Invalid DNS pointer.");
+                    }
+
+                    if (++pointerCount > 64)
+                    {
+                        throw new InvalidDataException("Too many DNS compression pointers.");
+                    }
+
+                    if (endOffset < 0)
+                    {
+                        endOffset = position + 2;
+                    }
+
+                    var pointer = ((length & 0x3F) << 8) | message[position + 1];
+                    position = pointer;
+                    continue;
+                }
+
+                // Reserved label types.
+                if ((length & 0xC0) != 0)
+                {
+                    throw new InvalidDataException("Invalid DNS label.");
+                }
+
+                position++;
+                if (position + length > message.Length)
+                {
+                    throw new InvalidDataException("Invalid DNS label length.");
+                }
+
+                if (name.Length > 0)
+                {
+                    name.Append('.');
+                }
+
+                name.Append(Encoding.ASCII.GetString(message.Slice(position, length)));
+                position += length;
+            }
+
+            nextOffset = endOffset;
+            return name.ToString();
+        }
+
+        public sealed record DnsResponse(List<IPAddress> Addresses, string? Cname);
+
+        private static string? NormalizeName(string name)
+        {
+            name = name.TrimEnd('.');
+            return name.Length == 0 ? null : name;
+        }
+
+        private static bool NamesEqual(string? left, string? right)
+        {
+            return left is not null &&
+                   right is not null &&
+                   string.Equals(
+                       left.TrimEnd('.'),
+                       right.TrimEnd('.'),
+                       StringComparison.OrdinalIgnoreCase);
+        }
+
+        private static ushort ReadUInt16(
+            ReadOnlySpan<byte> data,
+            int offset)
+        {
+            return (ushort)(
+                (data[offset] << 8) |
+                data[offset + 1]);
+        }
+
+        #endregion
+    }
+
+    public interface IDnsResolver
+    {
+        public Task<List<IPAddress>> ResolveAsync(
+            string host,
+            bool ipv6,
+            CancellationToken cancellationToken = default);
+
+        public async Task<List<IPAddress>> ResolveIpv46Async(
+            string host,
+            CancellationToken cancellationToken = default)
+        {
+            var ipv4Task = ResolveAsync(host, false, cancellationToken);
+            var ipv6Task = ResolveAsync(host, true, cancellationToken);
+            var results = await Task.WhenAll(ipv4Task, ipv6Task);
+            return results.SelectMany(x => x).ToList();
+        }
+    }
+
+    public class UdpDnsResolver(IPEndPoint dnsServer) : IDnsResolver
+    {
+        public async Task<List<IPAddress>> ResolveAsync(
+            string host,
+            bool ipv6,
+            CancellationToken cancellationToken = default)
+        {
+            return await DnsWire.ResolveWithCnameAsync(
+                host,
+                ipv6,
+                async (name, queryType, ct) =>
+                {
+                    var query = DnsWire.BuildQuery(name, queryType);
+                    using var udpClient = new UdpClient();
+                    udpClient.Connect(dnsServer);
+                    await udpClient.SendAsync(query, query.Length);
+                    var result = await udpClient.ReceiveAsync(ct);
+                    return result.Buffer;
+                },
+                cancellationToken);
+        }
+    }
+
+    public class TcpDnsResolver(IPEndPoint dnsServer) : IDnsResolver
+    {
+        public async Task<List<IPAddress>> ResolveAsync(
+            string host,
+            bool ipv6,
+            CancellationToken cancellationToken = default)
+        {
+            return await DnsWire.ResolveWithCnameAsync(
+                host,
+                ipv6,
+                async (name, queryType, ct) =>
+                {
+                    var query = DnsWire.BuildQuery(name, queryType);
+                    using var tcpClient = new TcpClient();
+                    await tcpClient.ConnectAsync(dnsServer.Address, dnsServer.Port, ct);
+                    await using var networkStream = tcpClient.GetStream();
+                    await networkStream.WriteAsync(query, 0, query.Length, ct);
+                    // Read the length of the response (2 bytes)
+                    var lengthBuffer = new byte[2];
+                    await networkStream.ReadExactlyAsync(lengthBuffer, 0, 2, ct);
+                    var responseLength = (lengthBuffer[0] << 8) | lengthBuffer[1];
+                    // Read the actual response
+                    var responseBuffer = new byte[responseLength];
+                    await networkStream.ReadExactlyAsync(responseBuffer, 0, responseLength, ct);
+                    return responseBuffer;
+                },
+                cancellationToken);
+        }
+    }
+
+    public class DohDnsResolver(HttpClient httpClient, Uri dohServer) : IDnsResolver
+    {
+        public async Task<List<IPAddress>> ResolveAsync(
+            string host,
+            bool ipv6,
+            CancellationToken cancellationToken = default)
+        {
+            return await DnsWire.ResolveWithCnameAsync(
+                host,
+                ipv6,
+                async (name, queryType, ct) =>
+                {
+                    var query = DnsWire.BuildQuery(name, queryType);
+
+                    using var request = new HttpRequestMessage(HttpMethod.Post, dohServer);
+                    request.Content = new ByteArrayContent(query)
+                    {
+                        Headers =
+                        {
+                            ContentType = new MediaTypeHeaderValue("application/dns-message"),
+                        },
+                    };
+
+                    request.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/dns-message"));
+
+                    using var response =
+                        await httpClient.SendAsync(request, HttpCompletionOption.ResponseHeadersRead, ct);
+                    response.EnsureSuccessStatusCode();
+
+                    return await response.Content.ReadAsByteArrayAsync(ct);
+                },
+                cancellationToken);
+        }
+    }
+
+    public class SystemDnsResolver : IDnsResolver
+    {
+        public async Task<List<IPAddress>> ResolveAsync(
+            string host,
+            bool ipv6,
+            CancellationToken cancellationToken = default)
+        {
+            var addresses = await Dns.GetHostAddressesAsync(host, cancellationToken);
+            return addresses.Where(ip => (!ipv6 && ip.AddressFamily == AddressFamily.InterNetwork) ||
+                                         (ipv6 && ip.AddressFamily == AddressFamily.InterNetworkV6))
+                .ToList();
+        }
+
+        public async Task<List<IPAddress>> ResolveIpv46Async(
+            string host,
+            CancellationToken cancellationToken = default)
+        {
+            var addresses = await Dns.GetHostAddressesAsync(host, cancellationToken);
+            return addresses.ToList();
+        }
+    }
+}

v2rayN/ServiceLib/Models/Entities/SubItem.cs

@@ -36,4 +36,6 @@ public class SubItem
     public string? Memo { get; set; }
 
     public ECoreType? CustomCoreType { get; set; }
+
+    public string? PreResolver { get; set; }
 }

v2rayN/ServiceLib/Resx/ResUI.Designer.cs

@@ -528,6 +528,15 @@ namespace ServiceLib.Resx {
             }
         }
         
+        /// <summary>
+        ///   查找类似 Pre-resolve server domains 的本地化字符串。
+        /// </summary>
+        public static string LvPreResolve {
+            get {
+                return ResourceManager.GetString("LvPreResolve", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   查找类似 Previous proxy remarks 的本地化字符串。
         /// </summary>

v2rayN/ServiceLib/Resx/ResUI.resx

@@ -1911,4 +1911,7 @@ The "Get Certificate" action may fail if a self-signed certificate is used or if
   <data name="TbWarp" xml:space="preserve">
     <value>Warp</value>
   </data>
+  <data name="LvPreResolve" xml:space="preserve">
+    <value>Pre-resolve server domains</value>
+  </data>
 </root>

v2rayN/ServiceLib/Resx/ResUI.zh-Hans.resx

@@ -1903,4 +1903,7 @@
   <data name="TbWarp" xml:space="preserve">
     <value>Warp</value>
   </data>
+  <data name="LvPreResolve" xml:space="preserve">
+    <value>预解析节点域名</value>
+  </data>
 </root>

v2rayN/v2rayN.Desktop/Views/SubEditWindow.axaml

@@ -34,7 +34,7 @@
         </StackPanel>
         <ScrollViewer HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Auto">
 
-            <Grid ColumnDefinitions="Auto,400,Auto" RowDefinitions="Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto">
+            <Grid ColumnDefinitions="Auto,400,Auto" RowDefinitions="Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto">
 
                 <TextBlock
                     Grid.Row="0"
@@ -187,18 +187,33 @@
                     Grid.Row="8"
                     Grid.Column="0"
                     Margin="{StaticResource Margin4}"
+                    VerticalAlignment="Center"
+                    Text="{x:Static resx:ResUI.LvPreResolve}" />
+                <ComboBox
+                    x:Name="cmbPreResolve"
+                    Grid.Row="8"
+                    Grid.Column="1"
+                    Margin="{StaticResource Margin4}"
+                    VerticalAlignment="Center"
+                    IsEditable="True"
+                    PlaceholderText="{x:Static resx:ResUI.SubUrlTips}" />
+
+                <TextBlock
+                    Grid.Row="9"
+                    Grid.Column="0"
+                    Margin="{StaticResource Margin4}"
                     VerticalAlignment="Top"
                     Text="{x:Static resx:ResUI.LvRequestHeaders}" />
-                <StackPanel Grid.Row="8" Grid.Column="1">
+                <StackPanel Grid.Row="9" Grid.Column="1">
                     <TextBox
                         x:Name="txtRequestHeaders"
                         Margin="{StaticResource Margin4}"
                         AcceptsReturn="True"
-                        MinLines="4"
-                        MaxLines="8"
                         Classes="TextArea"
-                        TextWrapping="Wrap"
+                        MaxLines="8"
-                        ScrollViewer.VerticalScrollBarVisibility="Auto" />
+                        MinLines="4"
+                        ScrollViewer.VerticalScrollBarVisibility="Auto"
+                        TextWrapping="Wrap" />
                     <TextBlock
                         Margin="{StaticResource Margin4}"
                         Text="{x:Static resx:ResUI.SubRequestHeadersTips}"
@@ -206,28 +221,28 @@
                 </StackPanel>
 
                 <TextBlock
-                    Grid.Row="9"
+                    Grid.Row="10"
                     Grid.Column="0"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
                     Text="{x:Static resx:ResUI.LvSort}" />
                 <TextBox
                     x:Name="txtSort"
-                    Grid.Row="9"
+                    Grid.Row="10"
                     Grid.Column="1"
                     Width="100"
                     Margin="{StaticResource Margin4}"
                     HorizontalAlignment="Left" />
 
                 <TextBlock
-                    Grid.Row="10"
+                    Grid.Row="11"
                     Grid.Column="0"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
                     Text="{x:Static resx:ResUI.LvPrevProfile}" />
                 <TextBox
                     x:Name="txtPrevProfile"
-                    Grid.Row="10"
+                    Grid.Row="11"
                     Grid.Column="1"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
@@ -235,20 +250,20 @@
                     ToolTip.Tip="{x:Static resx:ResUI.LvPrevProfileTip}" />
                 <Button
                     x:Name="btnSelectPrevProfile"
-                    Grid.Row="10"
+                    Grid.Row="11"
                     Grid.Column="2"
                     Margin="{StaticResource Margin4}"
                     Content="{x:Static resx:ResUI.TbSelectProfile}" />
 
                 <TextBlock
-                    Grid.Row="11"
+                    Grid.Row="12"
                     Grid.Column="0"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
                     Text="{x:Static resx:ResUI.LvNextProfile}" />
                 <TextBox
                     x:Name="txtNextProfile"
-                    Grid.Row="11"
+                    Grid.Row="12"
                     Grid.Column="1"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
@@ -256,34 +271,34 @@
                     ToolTip.Tip="{x:Static resx:ResUI.LvPrevProfileTip}" />
                 <Button
                     x:Name="btnSelectNextProfile"
-                    Grid.Row="11"
+                    Grid.Row="12"
                     Grid.Column="2"
                     Margin="{StaticResource Margin4}"
                     Content="{x:Static resx:ResUI.TbSelectProfile}" />
 
                 <TextBlock
-                    Grid.Row="12"
+                    Grid.Row="13"
                     Grid.Column="0"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
                     Text="{x:Static resx:ResUI.LvCustomCoreType}" />
                 <ComboBox
                     x:Name="cmbCustomCoreType"
-                    Grid.Row="12"
+                    Grid.Row="13"
                     Grid.Column="1"
                     Width="200"
                     Margin="{StaticResource Margin4}"
                     HorizontalAlignment="Left" />
 
                 <TextBlock
-                    Grid.Row="13"
+                    Grid.Row="14"
                     Grid.Column="0"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
                     Text="{x:Static resx:ResUI.TbPreSocksPort4Sub}" />
                 <TextBox
                     x:Name="txtPreSocksPort"
-                    Grid.Row="13"
+                    Grid.Row="14"
                     Grid.Column="1"
                     Width="200"
                     Margin="{StaticResource Margin4}"
@@ -292,14 +307,14 @@
                     ToolTip.Tip="{x:Static resx:ResUI.TipPreSocksPort}" />
 
                 <TextBlock
-                    Grid.Row="14"
+                    Grid.Row="15"
                     Grid.Column="0"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
                     Text="{x:Static resx:ResUI.LvMemo}" />
                 <TextBox
                     x:Name="txtMemo"
-                    Grid.Row="14"
+                    Grid.Row="15"
                     Grid.Column="1"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"

v2rayN/v2rayN.Desktop/Views/SubEditWindow.axaml.cs

@@ -12,6 +12,7 @@ public partial class SubEditWindow : WindowBase<SubEditViewModel>
         btnCancel.Click += (s, e) => Close();
 
         cmbConvertTarget.ItemsSource = Global.SubConvertTargets;
+        cmbPreResolve.ItemsSource = Global.DomainDNS4PreResolveAddress;
         cmbCustomCoreType.ItemsSource = Utils.GetEnumNames<ECoreType>().Where(t => t != nameof(ECoreType.v2rayN)).ToList().AppendEmpty();
 
         this.WhenActivated(disposables =>
@@ -31,6 +32,7 @@ public partial class SubEditWindow : WindowBase<SubEditViewModel>
             this.Bind(ViewModel, vm => vm.SelectedSource.PreSocksPort, v => v.txtPreSocksPort.Text).DisposeWith(disposables);
             this.Bind(ViewModel, vm => vm.SelectedSource.Memo, v => v.txtMemo.Text).DisposeWith(disposables);
             this.Bind(ViewModel, vm => vm.CustomCoreType, v => v.cmbCustomCoreType.SelectedValue).DisposeWith(disposables);
+            this.Bind(ViewModel, vm => vm.SelectedSource.PreResolver, v => v.cmbPreResolve.Text).DisposeWith(disposables);
 
             this.BindCommand(ViewModel, vm => vm.SelectPrevProfileCmd, v => v.btnSelectPrevProfile).DisposeWith(disposables);
             this.BindCommand(ViewModel, vm => vm.SelectNextProfileCmd, v => v.btnSelectNextProfile).DisposeWith(disposables);

v2rayN/v2rayN/Views/SubEditWindow.xaml

@@ -66,6 +66,7 @@
                     <RowDefinition Height="Auto" />
                     <RowDefinition Height="Auto" />
                     <RowDefinition Height="Auto" />
+                    <RowDefinition Height="Auto" />
                 </Grid.RowDefinitions>
                 <Grid.ColumnDefinitions>
                     <ColumnDefinition Width="Auto" />
@@ -232,15 +233,31 @@
                     Grid.Row="8"
                     Grid.Column="0"
                     Margin="{StaticResource Margin4}"
+                    VerticalAlignment="Center"
+                    Text="{x:Static resx:ResUI.LvPreResolve}" />
+                <ComboBox
+                    x:Name="cmbPreResolve"
+                    Grid.Row="8"
+                    Grid.Column="1"
+                    Margin="{StaticResource Margin4}"
+                    VerticalAlignment="Center"
+                    materialDesign:HintAssist.Hint="{x:Static resx:ResUI.SubUrlTips}"
+                    IsEditable="True"
+                    Style="{StaticResource DefComboBox}" />
+
+                <TextBlock
+                    Grid.Row="9"
+                    Grid.Column="0"
+                    Margin="{StaticResource Margin4}"
                     VerticalAlignment="Top"
                     Text="{x:Static resx:ResUI.LvRequestHeaders}" />
-                <StackPanel Grid.Row="8" Grid.Column="1">
+                <StackPanel Grid.Row="9" Grid.Column="1">
                     <TextBox
                         x:Name="txtRequestHeaders"
                         Margin="{StaticResource Margin4}"
                         AcceptsReturn="True"
-                        MinLines="4"
                         MaxLines="8"
+                        MinLines="4"
                         Style="{StaticResource MyOutlinedTextBox}"
                         TextWrapping="Wrap"
                         VerticalScrollBarVisibility="Auto" />
@@ -251,7 +268,7 @@
                 </StackPanel>
 
                 <TextBlock
-                    Grid.Row="9"
+                    Grid.Row="10"
                     Grid.Column="0"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
@@ -259,7 +276,7 @@
                     Text="{x:Static resx:ResUI.LvSort}" />
                 <TextBox
                     x:Name="txtSort"
-                    Grid.Row="9"
+                    Grid.Row="10"
                     Grid.Column="1"
                     Width="100"
                     Margin="{StaticResource Margin4}"
@@ -269,7 +286,7 @@
                     Style="{StaticResource MyOutlinedTextBox}" />
 
                 <TextBlock
-                    Grid.Row="10"
+                    Grid.Row="11"
                     Grid.Column="0"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
@@ -277,7 +294,7 @@
                     Text="{x:Static resx:ResUI.LvPrevProfile}" />
                 <TextBox
                     x:Name="txtPrevProfile"
-                    Grid.Row="10"
+                    Grid.Row="11"
                     Grid.Column="1"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
@@ -287,7 +304,7 @@
                     ToolTip="{x:Static resx:ResUI.LvPrevProfileTip}" />
                 <Button
                     x:Name="btnSelectPrevProfile"
-                    Grid.Row="10"
+                    Grid.Row="11"
                     Grid.Column="2"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
@@ -295,7 +312,7 @@
                     Style="{StaticResource DefButton}" />
 
                 <TextBlock
-                    Grid.Row="11"
+                    Grid.Row="12"
                     Grid.Column="0"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
@@ -303,7 +320,7 @@
                     Text="{x:Static resx:ResUI.LvNextProfile}" />
                 <TextBox
                     x:Name="txtNextProfile"
-                    Grid.Row="11"
+                    Grid.Row="12"
                     Grid.Column="1"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
@@ -313,7 +330,7 @@
                     ToolTip="{x:Static resx:ResUI.LvPrevProfileTip}" />
                 <Button
                     x:Name="btnSelectNextProfile"
-                    Grid.Row="11"
+                    Grid.Row="12"
                     Grid.Column="2"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
@@ -321,7 +338,7 @@
                     Style="{StaticResource DefButton}" />
 
                 <TextBlock
-                    Grid.Row="12"
+                    Grid.Row="13"
                     Grid.Column="0"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
@@ -329,14 +346,14 @@
                     Text="{x:Static resx:ResUI.LvCustomCoreType}" />
                 <ComboBox
                     x:Name="cmbCustomCoreType"
-                    Grid.Row="12"
+                    Grid.Row="13"
                     Grid.Column="1"
                     Margin="{StaticResource Margin4}"
                     MaxDropDownHeight="1000"
                     Style="{StaticResource MyOutlinedTextComboBox}" />
 
                 <TextBlock
-                    Grid.Row="13"
+                    Grid.Row="14"
                     Grid.Column="0"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
@@ -344,7 +361,7 @@
                     Text="{x:Static resx:ResUI.TbPreSocksPort4Sub}" />
                 <TextBox
                     x:Name="txtPreSocksPort"
-                    Grid.Row="13"
+                    Grid.Row="14"
                     Grid.Column="1"
                     Margin="{StaticResource Margin4}"
                     HorizontalAlignment="Left"
@@ -354,7 +371,7 @@
                     ToolTip="{x:Static resx:ResUI.TipPreSocksPort}" />
 
                 <TextBlock
-                    Grid.Row="14"
+                    Grid.Row="15"
                     Grid.Column="0"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"
@@ -362,7 +379,7 @@
                     Text="{x:Static resx:ResUI.LvMemo}" />
                 <TextBox
                     x:Name="txtMemo"
-                    Grid.Row="14"
+                    Grid.Row="15"
                     Grid.Column="1"
                     Margin="{StaticResource Margin4}"
                     VerticalAlignment="Center"

v2rayN/v2rayN/Views/SubEditWindow.xaml.cs

@@ -9,6 +9,7 @@ public partial class SubEditWindow
         Loaded += Window_Loaded;
 
         cmbConvertTarget.ItemsSource = Global.SubConvertTargets;
+        cmbPreResolve.ItemsSource = Global.DomainDNS4PreResolveAddress;
         cmbCustomCoreType.ItemsSource = Utils.GetEnumNames<ECoreType>().Where(t => t != nameof(ECoreType.v2rayN)).ToList().AppendEmpty();
 
         this.WhenActivated(disposables =>
@@ -28,6 +29,7 @@ public partial class SubEditWindow
             this.Bind(ViewModel, vm => vm.SelectedSource.PreSocksPort, v => v.txtPreSocksPort.Text).DisposeWith(disposables);
             this.Bind(ViewModel, vm => vm.SelectedSource.Memo, v => v.txtMemo.Text).DisposeWith(disposables);
             this.Bind(ViewModel, vm => vm.CustomCoreType, v => v.cmbCustomCoreType.Text).DisposeWith(disposables);
+            this.Bind(ViewModel, vm => vm.SelectedSource.PreResolver, v => v.cmbPreResolve.Text).DisposeWith(disposables);
 
             this.BindCommand(ViewModel, vm => vm.SelectPrevProfileCmd, v => v.btnSelectPrevProfile).DisposeWith(disposables);
             this.BindCommand(ViewModel, vm => vm.SelectNextProfileCmd, v => v.btnSelectNextProfile).DisposeWith(disposables);