Do not expose the config secret in URL, and use {net.CryptoCode}.external.lnd.grpc argument

BTCPayServer/Configuration/BTCPayServerOptions.cs

@@ -74,23 +74,40 @@ namespace BTCPayServer.Configuration
                 setting.ExplorerUri = conf.GetOrDefault<Uri>($"{net.CryptoCode}.explorer.url", net.NBXplorerNetwork.DefaultSettings.DefaultUrl);
                 setting.CookieFile = conf.GetOrDefault<string>($"{net.CryptoCode}.explorer.cookiefile", net.NBXplorerNetwork.DefaultSettings.DefaultCookieFile);
                 NBXplorerConnectionSettings.Add(setting);
-                var lightning = conf.GetOrDefault<string>($"{net.CryptoCode}.lightning", string.Empty);
-                if(lightning.Length != 0)
                 {
-                    if(!LightningConnectionString.TryParse(lightning, true, out var connectionString, out var error))
+                    var lightning = conf.GetOrDefault<string>($"{net.CryptoCode}.lightning", string.Empty);
+                    if (lightning.Length != 0)
                     {
-                        throw new ConfigException($"Invalid setting {net.CryptoCode}.lightning, " + Environment.NewLine +
+                        if (!LightningConnectionString.TryParse(lightning, true, out var connectionString, out var error))
-                            $"If you have a lightning server use: 'type=clightning;server=/root/.lightning/lightning-rpc', " + Environment.NewLine +
+                        {
-                            $"If you have a lightning charge server: 'type=charge;server=https://charge.example.com;api-token=yourapitoken'" + Environment.NewLine +
+                            throw new ConfigException($"Invalid setting {net.CryptoCode}.lightning, " + Environment.NewLine +
-                            $"If you have a lnd server: 'type=lnd-rest;server=https://lnd:lnd@lnd.example.com;macaroon=abf239...;certthumbprint=2abdf302...'" + Environment.NewLine +
+                                $"If you have a lightning server use: 'type=clightning;server=/root/.lightning/lightning-rpc', " + Environment.NewLine +
-                            $"              lnd server: 'type=lnd-rest;server=https://lnd:lnd@lnd.example.com;macaroonfilepath=/root/.lnd/admin.macaroon;certthumbprint=2abdf302...'" + Environment.NewLine +
+                                $"If you have a lightning charge server: 'type=charge;server=https://charge.example.com;api-token=yourapitoken'" + Environment.NewLine +
-                            error);
+                                $"If you have a lnd server: 'type=lnd-rest;server=https://lnd:lnd@lnd.example.com;macaroon=abf239...;certthumbprint=2abdf302...'" + Environment.NewLine +
+                                $"              lnd server: 'type=lnd-rest;server=https://lnd:lnd@lnd.example.com;macaroonfilepath=/root/.lnd/admin.macaroon;certthumbprint=2abdf302...'" + Environment.NewLine +
+                                error);
+                        }
+                        if (connectionString.IsLegacy)
+                        {
+                            Logs.Configuration.LogWarning($"Setting {net.CryptoCode}.lightning will work but use an deprecated format, please replace it by '{connectionString.ToString()}'");
+                        }
+                        InternalLightningByCryptoCode.Add(net.CryptoCode, connectionString);
                     }
-                    if(connectionString.IsLegacy)
+                }
+
+                {
+                    var lightning = conf.GetOrDefault<string>($"{net.CryptoCode}.external.lnd.grpc", string.Empty);
+                    if (lightning.Length != 0)
                     {
-                        Logs.Configuration.LogWarning($"Setting {net.CryptoCode}.lightning will work but use an deprecated format, please replace it by '{connectionString.ToString()}'");
+                        if (!LightningConnectionString.TryParse(lightning, false, out var connectionString, out var error))
+                        {
+                            throw new ConfigException($"Invalid setting {net.CryptoCode}.external.lnd.grpc, " + Environment.NewLine +
+                                $"lnd server: 'type=lnd-grpc;server=https://lnd.example.com;macaroon=abf239...;certthumbprint=2abdf302...'" + Environment.NewLine +
+                                $"lnd server: 'type=lnd-grpc;server=https://lnd.example.com;macaroonfilepath=/root/.lnd/admin.macaroon;certthumbprint=2abdf302...'" + Environment.NewLine +
+                                error);
+                        }
+                        ExternalServicesByCryptoCode.Add(net.CryptoCode, new ExternalLNDGRPC(connectionString));
                     }
-                    InternalLightningByCryptoCode.Add(net.CryptoCode, connectionString);
                 }
             }
 
@@ -104,11 +121,12 @@ namespace BTCPayServer.Configuration
             if (!RootPath.StartsWith("/", StringComparison.InvariantCultureIgnoreCase))
                 RootPath = "/" + RootPath;
             var old = conf.GetOrDefault<Uri>("internallightningnode", null);
-            if(old != null)
+            if (old != null)
                 throw new ConfigException($"internallightningnode should not be used anymore, use btclightning instead");
         }
         public string RootPath { get; set; }
         public Dictionary<string, LightningConnectionString> InternalLightningByCryptoCode { get; set; } = new Dictionary<string, LightningConnectionString>();
+        public ExternalServices ExternalServicesByCryptoCode { get; set; } = new ExternalServices();
 
         public BTCPayNetworkProvider NetworkProvider { get; set; }
         public string PostgresConnectionString
@@ -136,4 +154,29 @@ namespace BTCPayServer.Configuration
             return builder.ToString();
         }
     }
+    
+    public class ExternalServices : MultiValueDictionary<string, ExternalService>
+    {
+        public IEnumerable<T> GetServices<T>(string cryptoCode) where T : ExternalService
+        {
+            if (!this.TryGetValue(cryptoCode.ToUpperInvariant(), out var services))
+                return Array.Empty<T>();
+            return services.OfType<T>();
+        }
+    }
+
+    public class ExternalService
+    {
+
+    }
+
+    public class ExternalLNDGRPC : ExternalService
+    {
+        public ExternalLNDGRPC(LightningConnectionString connectionString)
+        {
+            ConnectionString = connectionString;
+        }
+
+        public LightningConnectionString ConnectionString { get; set; }
+    }
 }

BTCPayServer/Configuration/DefaultConfiguration.cs

@@ -40,6 +40,7 @@ namespace BTCPayServer.Configuration
                 app.Option($"--{crypto}explorerurl", $"URL of the NBXplorer for {network.CryptoCode} (default: {network.NBXplorerNetwork.DefaultSettings.DefaultUrl})", CommandOptionType.SingleValue);
                 app.Option($"--{crypto}explorercookiefile", $"Path to the cookie file (default: {network.NBXplorerNetwork.DefaultSettings.DefaultCookieFile})", CommandOptionType.SingleValue);
                 app.Option($"--{crypto}lightning", $"Easy configuration of lightning for the server administrator: Must be a UNIX socket of c-lightning (lightning-rpc) or URL to a charge server (default: empty)", CommandOptionType.SingleValue);
+                app.Option($"--{crypto}externallndgrpc", $"The LND gRPC configuration BTCPay will expose to easily connect to the internal lnd wallet from Zap wallet (default: empty)", CommandOptionType.SingleValue);
             }
             return app;
         }

BTCPayServer/Controllers/ServerController.cs

@@ -11,6 +11,7 @@ using BTCPayServer.Validations;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Identity;
 using Microsoft.AspNetCore.Mvc;
+using NBitcoin;
 using NBitcoin.DataEncoders;
 using System;
 using System.Collections.Generic;
@@ -238,65 +239,31 @@ namespace BTCPayServer.Controllers
         public IActionResult Services()
         {
             var result = new ServicesViewModel();
-            foreach (var internalNode in _Options.InternalLightningByCryptoCode)
+            foreach (var cryptoCode in _Options.ExternalServicesByCryptoCode.Keys)
             {
-                //Only BTC can be supported because gRPC does not allow http path rewriting.
-                if (internalNode.Key == "BTC" && GetExternalLNDConnectionString(internalNode.Value) != null)
                 {
-                    result.LNDServices.Add(new ServicesViewModel.LNDServiceViewModel()
+                    int i = 0;
+                    foreach (var grpcService in _Options.ExternalServicesByCryptoCode.GetServices<ExternalLNDGRPC>(cryptoCode))
                     {
-                        Crypto = internalNode.Key,
+                        result.LNDServices.Add(new ServicesViewModel.LNDServiceViewModel()
-                        Type = "gRPC"
+                        {
-                    });
+                            Crypto = cryptoCode,
+                            Type = "gRPC",
+                            Index = i++,
+                        });
+                    }
                 }
             }
             return View(result);
         }
 
-        private LightningConnectionString GetExternalLNDConnectionString(LightningConnectionString value)
+        [Route("server/services/lnd-grpc/{cryptoCode}/{index}")]
+        public IActionResult LNDGRPCServices(string cryptoCode, int index, uint? nonce)
         {
-            if (value.ConnectionType != LightningConnectionType.LndREST)
+            var external = GetExternalLNDConnectionString(cryptoCode, index);
-                return null;
+            if (external == null)
-            var external = new LightningConnectionString();
-            external.ConnectionType = LightningConnectionType.LndREST;
-            external.BaseUri = _Options.ExternalUrl ?? value.BaseUri;
-            if (external.BaseUri.Scheme == "http" || value.AllowInsecure)
-            {
-                external.AllowInsecure = true;
-            }
-
-            try
-            {
-                if (value.MacaroonFilePath != null)
-                    external.Macaroon = System.IO.File.ReadAllBytes(value.MacaroonFilePath);
-            }
-            catch
-            {
-                return null;
-            }
-            if (value.Macaroon != null)
-                external.Macaroon = value.Macaroon;
-
-            // If external url is provided, then we don't care about cert thumbprint
-            // because we override it at the reverse proxy level with a trusted certificate
-            if (_Options.ExternalUrl == null)
-            {
-                if (value.CertificateThumbprint != null)
-                {
-                    external.CertificateThumbprint = value.CertificateThumbprint;
-                    external.AllowInsecure = false;
-                }
-            }
-            return external;
-        }
-
-        [Route("server/services/lnd-grpc/{cryptoCode}")]
-        public IActionResult LNDGRPCServices(string cryptoCode, ulong? secret)
-        {
-            if (!_Options.InternalLightningByCryptoCode.TryGetValue(cryptoCode.ToUpperInvariant(), out var connectionString))
                 return NotFound();
             var model = new LNDGRPCServicesViewModel();
-            var external = GetExternalLNDConnectionString(connectionString);
 
             model.Host = $"{external.BaseUri.DnsSafeHost}:{external.BaseUri.Port}";
             model.SSL = external.BaseUri.Scheme == "https";
@@ -308,34 +275,43 @@ namespace BTCPayServer.Controllers
             {
                 model.Macaroon = Encoders.Hex.EncodeData(external.Macaroon);
             }
-            if (secret != null)
+
+            if (nonce != null)
             {
-                var lnConfig = _LnConfigProvider.GetConfig(secret.Value);
+                var configKey = GetConfigKey("lnd-grpc", cryptoCode, index, nonce.Value);
+                var lnConfig = _LnConfigProvider.GetConfig(configKey);
                 if (lnConfig != null)
                 {
-                    model.QRCodeLink = $"{this.Request.GetAbsoluteRoot().WithTrailingSlash()}lnd-config/{secret.Value}/lnd.config";
+                    model.QRCodeLink = $"{this.Request.GetAbsoluteRoot().WithTrailingSlash()}lnd-config/{configKey}/lnd.config";
                     model.QRCode = $"config={model.QRCodeLink}";
                 }
             }
+
             return View(model);
         }
-        [Route("lnd-config/{secret}/lnd.config")]
+
-        [AllowAnonymous]
+        private static uint GetConfigKey(string type, string cryptoCode, int index, uint nonce)
-        public IActionResult GetLNDConfig(ulong secret)
         {
-            var conf = _LnConfigProvider.GetConfig(secret);
+            return (uint)HashCode.Combine(type, cryptoCode, index, nonce);
+        }
+
+        [Route("lnd-config/{configKey}/lnd.config")]
+        [AllowAnonymous]
+        public IActionResult GetLNDConfig(uint configKey)
+        {
+            var conf = _LnConfigProvider.GetConfig(configKey);
             if (conf == null)
                 return NotFound();
             return Json(conf);
         }
 
-        [Route("server/services/lnd-grpc/{cryptoCode}")]
+        [Route("server/services/lnd-grpc/{cryptoCode}/{index}")]
         [HttpPost]
-        public IActionResult LNDGRPCServicesPOST(string cryptoCode)
+        public IActionResult LNDGRPCServicesPOST(string cryptoCode, int index)
         {
-            if (!_Options.InternalLightningByCryptoCode.TryGetValue(cryptoCode.ToUpperInvariant(), out var connectionString))
+            var external = GetExternalLNDConnectionString(cryptoCode, index);
+            if (external == null)
                 return NotFound();
-            var external = GetExternalLNDConnectionString(connectionString);
             LightningConfigurations confs = new LightningConfigurations();
             LightningConfiguration conf = new LightningConfiguration();
             conf.Type = "grpc";
@@ -346,8 +322,16 @@ namespace BTCPayServer.Controllers
             conf.Macaroon = external.Macaroon == null ? null : Encoders.Hex.EncodeData(external.Macaroon);
             conf.CertificateThumbprint = external.CertificateThumbprint == null ? null : Encoders.Hex.EncodeData(external.CertificateThumbprint);
             confs.Configurations.Add(conf);
-            var secret = _LnConfigProvider.KeepConfig(confs);
+
-            return RedirectToAction(nameof(LNDGRPCServices), new { cryptoCode = cryptoCode, secret = secret });
+            var nonce = RandomUtils.GetUInt32();
+            var configKey = GetConfigKey("lnd-grpc", cryptoCode, index, nonce);
+            _LnConfigProvider.KeepConfig(configKey, confs);
+            return RedirectToAction(nameof(LNDGRPCServices), new { cryptoCode = cryptoCode, nonce = nonce });
+        }
+
+        private LightningConnectionString GetExternalLNDConnectionString(string cryptoCode, int index)
+        {
+            return _Options.ExternalServicesByCryptoCode.GetServices<ExternalLNDGRPC>(cryptoCode).Skip(index).Select(c => c.ConnectionString).FirstOrDefault();
         }
 
         [Route("server/theme")]

BTCPayServer/Models/ServerViewModels/ServicesViewModel.cs

@@ -11,6 +11,7 @@ namespace BTCPayServer.Models.ServerViewModels
         {
             public string Crypto { get; set; }
             public string Type { get; set; }
+            public int Index { get; set; }
         }
         public List<LNDServiceViewModel> LNDServices { get; set; } = new List<LNDServiceViewModel>();
     }

BTCPayServer/Properties/launchSettings.json

@@ -9,8 +9,8 @@
             "BTCPAY_BTCEXPLORERURL": "http://127.0.0.1:32838/",
             "ASPNETCORE_ENVIRONMENT": "Development",
             "BTCPAY_CHAINS": "btc,ltc",
-            "BTCPAY_BTCLIGHTNING": "http://api-token:foiewnccewuify@127.0.0.1:54938/",
+            "BTCPAY_BTCLIGHTNING": "type=charge;server=http://127.0.0.1:54938/;api-token=foiewnccewuify",
-            //"BTCPAY_BTCLIGHTNING": "type=lnd-rest;server=https://lnd:lnd@127.0.0.1:53280/;allowinsecure=true",
+            "BTCPAY_BTCEXTERNALLNDGRPC": "type=lnd-rest;server=https://lnd:lnd@127.0.0.1:53280/;allowinsecure=true",
             "BTCPAY_POSTGRES": "User ID=postgres;Host=127.0.0.1;Port=39372;Database=btcpayserver",
             "BTCPAY_BUNDLEJSCSS": "false"
         },

BTCPayServer/Services/LightningConfigurationProvider.cs

@@ -10,10 +10,9 @@ namespace BTCPayServer.Services
     public class LightningConfigurationProvider
     {
         ConcurrentDictionary<ulong, (DateTimeOffset expiration, LightningConfigurations config)> _Map = new ConcurrentDictionary<ulong, (DateTimeOffset expiration, LightningConfigurations config)>();
-        public ulong KeepConfig(LightningConfigurations configuration)
+        public ulong KeepConfig(ulong secret, LightningConfigurations configuration)
         {
             CleanExpired();
-            var secret = RandomUtils.GetUInt64();
             _Map.AddOrReplace(secret, (DateTimeOffset.UtcNow + TimeSpan.FromMinutes(10), configuration));
             return secret;
         }

BTCPayServer/Views/Server/Services.cshtml

@@ -37,7 +37,7 @@
                                 <td>@lnd.Crypto</td>
                                 <td>@lnd.Type</td>
                                 <td style="text-align:right">
-                                    <a asp-action="LNDGRPCServices" asp-route-cryptoCode="@lnd.Crypto">See information</a>
+                                    <a asp-action="LNDGRPCServices" asp-route-cryptoCode="@lnd.Crypto" asp-route-index="@lnd.Index">See information</a>
                                 </td>
                             </tr>
                         }