Add sing-box ech support (#8603)

* Add sing-box ech support

* Support group config type

* Simplified code

v2rayN/ServiceLib/Global.cs

@@ -88,6 +88,7 @@ public class Global
     public const string SingboxLocalDNSTag = "local_local";
     public const string SingboxHostsDNSTag = "hosts_dns";
     public const string SingboxFakeDNSTag = "fake_dns";
+    public const string SingboxEchDNSTag = "ech_dns";
 
     public static readonly List<string> IEProxyProtocols =
     [

v2rayN/ServiceLib/Manager/ProfileGroupItemManager.cs

@@ -316,5 +316,72 @@ public class ProfileGroupItemManager
         return childAddresses;
     }
 
+    public static async Task<HashSet<string>> GetAllChildEchQuerySni(string indexId)
+    {
+        // include grand children
+        var childAddresses = new HashSet<string>();
+        if (!Instance.TryGet(indexId, out var groupItem) || groupItem == null)
+        {
+            return childAddresses;
+        }
+
+        if (groupItem.SubChildItems.IsNotEmpty())
+        {
+            var subItems = await GetSubChildProfileItems(groupItem);
+            foreach (var childNode in subItems)
+            {
+                if (childNode.EchConfigList.IsNullOrEmpty())
+                {
+                    continue;
+                }
+                if (childNode.StreamSecurity == Global.StreamSecurity
+                    && childNode.EchConfigList?.Contains("://") == true)
+                {
+                    var idx = childNode.EchConfigList.IndexOf('+');
+                    childAddresses.Add(idx > 0 ? childNode.EchConfigList[..idx] : childNode.Sni);
+                }
+                else
+                {
+                    childAddresses.Add(childNode.Sni);
+                }
+            }
+        }
+
+        var childIds = Utils.String2List(groupItem.ChildItems) ?? [];
+
+        foreach (var childId in childIds)
+        {
+            var childNode = await AppManager.Instance.GetProfileItem(childId);
+            if (childNode == null)
+            {
+                continue;
+            }
+
+            if (!childNode.IsComplex() && !childNode.EchConfigList.IsNullOrEmpty())
+            {
+                if (childNode.StreamSecurity == Global.StreamSecurity
+                    && childNode.EchConfigList?.Contains("://") == true)
+                {
+                    var idx = childNode.EchConfigList.IndexOf('+');
+                    childAddresses.Add(idx > 0 ? childNode.EchConfigList[..idx] : childNode.Sni);
+                }
+                else
+                {
+                    childAddresses.Add(childNode.Sni);
+                }
+            }
+            else if (childNode.ConfigType.IsGroupType())
+            {
+                var subAddresses = await GetAllChildDomainAddresses(childNode.IndexId);
+                foreach (var addr in subAddresses)
+                {
+                    childAddresses.Add(addr);
+                }
+            }
+        }
+
+        return childAddresses;
+    }
+
     #endregion Helper
 }

v2rayN/ServiceLib/Models/SingboxConfig.cs

@@ -182,6 +182,14 @@ public class Tls4Sbox
     public string? fragment_fallback_delay { get; set; }
     public bool? record_fragment { get; set; }
     public List<string>? certificate { get; set; }
+    public Ech4Sbox? ech { get; set; }
+}
+
+public class Ech4Sbox
+{
+    public bool enabled { get; set; }
+    public List<string>? config { get; set; }
+    public string? query_server_name { get; set; }
 }
 
 public class Multiplex4Sbox

v2rayN/ServiceLib/Services/CoreConfig/Singbox/CoreConfigSingboxService.cs

@@ -371,7 +371,7 @@ public partial class CoreConfigSingboxService(Config config)
 
             await GenRouting(singboxConfig);
             await GenExperimental(singboxConfig);
-            await GenDns(null, singboxConfig);
+            await GenDns(parentNode, singboxConfig);
             await ConvertGeo2Ruleset(singboxConfig);
 
             ret.Success = true;
@@ -428,7 +428,7 @@ public partial class CoreConfigSingboxService(Config config)
 
             await GenRouting(singboxConfig);
             await GenExperimental(singboxConfig);
-            await GenDns(null, singboxConfig);
+            await GenDns(parentNode, singboxConfig);
             await ConvertGeo2Ruleset(singboxConfig);
 
             ret.Success = true;

v2rayN/ServiceLib/Services/CoreConfig/Singbox/SingboxDnsService.cs

@@ -13,8 +13,8 @@ public partial class CoreConfigSingboxService
             }
 
             var simpleDNSItem = _config.SimpleDNSItem;
-            await GenDnsServers(singboxConfig, simpleDNSItem);
+            await GenDnsServers(node, singboxConfig, simpleDNSItem);
-            await GenDnsRules(singboxConfig, simpleDNSItem);
+            await GenDnsRules(node, singboxConfig, simpleDNSItem);
 
             singboxConfig.dns ??= new Dns4Sbox();
             singboxConfig.dns.independent_cache = true;
@@ -52,7 +52,7 @@ public partial class CoreConfigSingboxService
         return 0;
     }
 
-    private async Task<int> GenDnsServers(SingboxConfig singboxConfig, SimpleDNSItem simpleDNSItem)
+    private async Task<int> GenDnsServers(ProfileItem? node, SingboxConfig singboxConfig, SimpleDNSItem simpleDNSItem)
     {
         var finalDns = await GenDnsDomains(singboxConfig, simpleDNSItem);
 
@@ -133,6 +133,29 @@ public partial class CoreConfigSingboxService
             singboxConfig.dns.servers.Add(fakeip);
         }
 
+        // ech
+        var (_, dnsServer) = ParseEchParam(node?.EchConfigList);
+        if (dnsServer is not null)
+        {
+            dnsServer.tag = Global.SingboxEchDNSTag;
+            if (dnsServer.server is not null
+                && hostsDns.predefined.ContainsKey(dnsServer.server))
+            {
+                dnsServer.domain_resolver = Global.SingboxHostsDNSTag;
+            }
+            else
+            {
+                dnsServer.domain_resolver = Global.SingboxLocalDNSTag;
+            }
+            singboxConfig.dns.servers.Add(dnsServer);
+        }
+        else if (node?.ConfigType.IsGroupType() == true)
+        {
+            var echDnsObject = JsonUtils.DeepCopy(directDns);
+            echDnsObject.tag = Global.SingboxEchDNSTag;
+            singboxConfig.dns.servers.Add(echDnsObject);
+        }
+
         return await Task.FromResult(0);
     }
 
@@ -146,7 +169,7 @@ public partial class CoreConfigSingboxService
         return await Task.FromResult(finalDns);
     }
 
-    private async Task<int> GenDnsRules(SingboxConfig singboxConfig, SimpleDNSItem simpleDNSItem)
+    private async Task<int> GenDnsRules(ProfileItem? node, SingboxConfig singboxConfig, SimpleDNSItem simpleDNSItem)
     {
         singboxConfig.dns ??= new Dns4Sbox();
         singboxConfig.dns.rules ??= new List<Rule4Sbox>();
@@ -168,6 +191,31 @@ public partial class CoreConfigSingboxService
             }
         });
 
+        var (ech, _) = ParseEchParam(node?.EchConfigList);
+        if (ech is not null)
+        {
+            var echDomain = ech.query_server_name ?? node?.Sni;
+            singboxConfig.dns.rules.Add(new()
+            {
+                query_type = new List<int> { 64, 65 },
+                server = Global.SingboxEchDNSTag,
+                domain = echDomain is not null ? new List<string> { echDomain } : null,
+            });
+        }
+        else if (node?.ConfigType.IsGroupType() == true)
+        {
+            var queryServerNames = (await ProfileGroupItemManager.GetAllChildEchQuerySni(node.IndexId)).ToList();
+            if (queryServerNames.Count > 0)
+            {
+                singboxConfig.dns.rules.Add(new()
+                {
+                    query_type = new List<int> { 64, 65 },
+                    server = Global.SingboxEchDNSTag,
+                    domain = queryServerNames,
+                });
+            }
+        }
+
         if (simpleDNSItem.BlockBindingQuery == true)
         {
             singboxConfig.dns.rules.Add(new()

v2rayN/ServiceLib/Services/CoreConfig/Singbox/SingboxOutboundService.cs

@@ -334,6 +334,11 @@ public partial class CoreConfigSingboxService
                 };
                 tls.insecure = false;
             }
+            var (ech, _) = ParseEchParam(node.EchConfigList);
+            if (ech is not null)
+            {
+                tls.ech = ech;
+            }
             outbound.tls = tls;
         }
         catch (Exception ex)
@@ -904,4 +909,31 @@ public partial class CoreConfigSingboxService
         }
         return await Task.FromResult(0);
     }
+
+    private (Ech4Sbox? ech, Server4Sbox? dnsServer) ParseEchParam(string? echConfig)
+    {
+        if (echConfig.IsNullOrEmpty())
+        {
+            return (null, null);
+        }
+        if (!echConfig.Contains("://"))
+        {
+            return (new Ech4Sbox()
+            {
+                enabled = true,
+                config = [$"-----BEGIN ECH CONFIGS-----\n" +
+                          $"{echConfig}\n" +
+                          $"-----END ECH CONFIGS-----"],
+            }, null);
+        }
+        var idx = echConfig.IndexOf('+');
+        // NOTE: query_server_name, since sing-box 1.13.0
+        //var queryServerName = idx > 0 ? echConfig[..idx] : null;
+        var echDnsServer = idx > 0 ? echConfig[(idx + 1)..] : echConfig;
+        return (new Ech4Sbox()
+        {
+            enabled = true,
+            query_server_name = null,
+        }, ParseDnsAddress(echDnsServer));
+    }
 }