From 2b11cc1077da194400490b73da8a872627866e81 Mon Sep 17 00:00:00 2001
From: "nicolas.dorier" <nicolas.dorier@gmail.com>
Date: Thu, 12 Apr 2018 11:48:33 +0900
Subject: [PATCH] Simplify root key path calculation

---
 BTCPayServer/BTCPayNetwork.cs                    |  8 +++++++-
 .../Controllers/StoresController.BTCLike.cs      |  6 ++----
 .../StoreViewModels/DerivationSchemeViewModel.cs |  3 ++-
 BTCPayServer/Services/HardwareWalletService.cs   | 16 ++++------------
 .../Views/Stores/AddDerivationScheme.cshtml      |  2 +-
 .../wwwroot/js/StoreAddDerivationScheme.js       |  1 -
 6 files changed, 16 insertions(+), 20 deletions(-)

diff --git a/BTCPayServer/BTCPayNetwork.cs b/BTCPayServer/BTCPayNetwork.cs
index 7bc0001ef..2b2bf4006 100644
--- a/BTCPayServer/BTCPayNetwork.cs
+++ b/BTCPayServer/BTCPayNetwork.cs
@@ -72,6 +72,12 @@ namespace BTCPayServer
         public override string ToString()
         {
             return CryptoCode;
-        }        
+        }
+
+        internal KeyPath GetRootKeyPath()
+        {
+            return new KeyPath(NBitcoinNetwork.Consensus.SupportSegwit ? "49'" : "44'")
+                        .Derive(CoinType); 
+        }
     }
 }
diff --git a/BTCPayServer/Controllers/StoresController.BTCLike.cs b/BTCPayServer/Controllers/StoresController.BTCLike.cs
index 9409041f7..0bb73d207 100644
--- a/BTCPayServer/Controllers/StoresController.BTCLike.cs
+++ b/BTCPayServer/Controllers/StoresController.BTCLike.cs
@@ -35,7 +35,7 @@ namespace BTCPayServer.Controllers
             DerivationSchemeViewModel vm = new DerivationSchemeViewModel();
             vm.ServerUrl = GetStoreUrl(storeId);
             vm.CryptoCode = cryptoCode;
-            vm.RootKeyPath = network.NBitcoinNetwork.Consensus.SupportSegwit ? "49'" : "44'";
+            vm.RootKeyPath = network.GetRootKeyPath();
             SetExistingValues(store, vm);
             return View(vm);
         }
@@ -69,7 +69,7 @@ namespace BTCPayServer.Controllers
             {
                 return NotFound();
             }
-            vm.RootKeyPath = network.NBitcoinNetwork.Consensus.SupportSegwit ? "49'" : "44'";
+            vm.RootKeyPath = network.GetRootKeyPath();
             var wallet = _WalletProvider.GetWallet(network);
             if (wallet == null)
             {
@@ -258,8 +258,6 @@ namespace BTCPayServer.Controllers
                 if (command == "getxpub")
                 {
                     var getxpubResult = await hw.GetExtPubKey(network, account);
-                    ;
-                    getxpubResult.CoinType = (int)(getxpubResult.KeyPath.Indexes[1] - 0x80000000);
                     result = getxpubResult;
                 }
                 if (command == "getinfo")
diff --git a/BTCPayServer/Models/StoreViewModels/DerivationSchemeViewModel.cs b/BTCPayServer/Models/StoreViewModels/DerivationSchemeViewModel.cs
index b67313d72..7e7d844ed 100644
--- a/BTCPayServer/Models/StoreViewModels/DerivationSchemeViewModel.cs
+++ b/BTCPayServer/Models/StoreViewModels/DerivationSchemeViewModel.cs
@@ -4,6 +4,7 @@ using System.ComponentModel.DataAnnotations;
 using System.Linq;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Mvc.Rendering;
+using NBitcoin;
 
 namespace BTCPayServer.Models.StoreViewModels
 {
@@ -29,6 +30,6 @@ namespace BTCPayServer.Models.StoreViewModels
 
         public string ServerUrl { get; set; }
         public string StatusMessage { get; internal set; }
-        public string RootKeyPath { get; set; }
+        public KeyPath RootKeyPath { get; set; }
     }
 }
diff --git a/BTCPayServer/Services/HardwareWalletService.cs b/BTCPayServer/Services/HardwareWalletService.cs
index 01c4236ab..3a138e918 100644
--- a/BTCPayServer/Services/HardwareWalletService.cs
+++ b/BTCPayServer/Services/HardwareWalletService.cs
@@ -84,19 +84,12 @@ namespace BTCPayServer.Services
                 throw new ArgumentNullException(nameof(network));
 
             var segwit = network.NBitcoinNetwork.Consensus.SupportSegwit;
-            var path = new KeyPath(segwit ? "49'" : "44'").Derive(network.CoinType).Derive(account, true);
+            var path = network.GetRootKeyPath().Derive(account, true);
             var pubkey = await GetExtPubKey(_Ledger, network, path, false);
-            var derivation = new DerivationStrategyFactory(network.NBitcoinNetwork).CreateDirectDerivationStrategy(pubkey,
-            segwit ? 
-            new DerivationStrategyOptions()
+            var derivation = new DerivationStrategyFactory(network.NBitcoinNetwork).CreateDirectDerivationStrategy(pubkey, new DerivationStrategyOptions()
             {
-                P2SH = true,
-                Legacy = false
-            } :
-            new DerivationStrategyOptions()
-            {
-                P2SH = false,
-                Legacy = true
+                P2SH = segwit,
+                Legacy = !segwit
             });
             return new GetXPubResult() { ExtPubKey = derivation.ToString(), KeyPath = path };
         }
@@ -248,6 +241,5 @@ namespace BTCPayServer.Services
         public string ExtPubKey { get; set; }
         [JsonConverter(typeof(NBitcoin.JsonConverters.KeyPathJsonConverter))]
         public KeyPath KeyPath { get; set; }
-        public int CoinType { get; internal set; }
     }
 }
diff --git a/BTCPayServer/Views/Stores/AddDerivationScheme.cshtml b/BTCPayServer/Views/Stores/AddDerivationScheme.cshtml
index 6e45c93d8..51c24364b 100644
--- a/BTCPayServer/Views/Stores/AddDerivationScheme.cshtml
+++ b/BTCPayServer/Views/Stores/AddDerivationScheme.cshtml
@@ -35,7 +35,7 @@
                         <ul>
                             @for (int i = 0; i < 4; i++)
                             {
-                                <li><a class="ledger-info-recommended" data-ledgeraccount="@i" href="#">Account @i (@Model.RootKeyPath/<span class="ledger-info-cointype">0</span>'/@i')</a></li>
+                                <li><a class="ledger-info-recommended" data-ledgeraccount="@i" href="#">Account @i (<span>@Model.RootKeyPath.Derive(i, true)</span>)</a></li>
                             }
                         </ul>
                     </div>
diff --git a/BTCPayServer/wwwroot/js/StoreAddDerivationScheme.js b/BTCPayServer/wwwroot/js/StoreAddDerivationScheme.js
index caea00502..0bb2a1951 100644
--- a/BTCPayServer/wwwroot/js/StoreAddDerivationScheme.js
+++ b/BTCPayServer/wwwroot/js/StoreAddDerivationScheme.js
@@ -52,7 +52,6 @@
                     Write('check', 'success', 'This store is configured to use your ledger');
                     $("#no-ledger-info").css("display", "none");
                     $("#ledger-info").css("display", "block");
-                    $(".ledger-info-cointype").text(result.coinType);
                 }
             });
     };