Feature: Add Insecure SSL support for electrum server

hellbender.xcodeproj/project.pbxproj

@@ -7,9 +7,10 @@
 	objects = {
 
 /* Begin PBXBuildFile section */
-		3C08EDBF2F5E3A8000C2268E /* BitcoinDevKit in Frameworks */ = {isa = PBXBuildFile; productRef = AA00000200000000000000D0 /* BitcoinDevKit */; };
 		3C08EDC02F5E3A8000C2268E /* URKit in Frameworks */ = {isa = PBXBuildFile; productRef = AA00000500000000000000D0 /* URKit */; };
 		3C08EDC12F5E3A8000C2268E /* URUI in Frameworks */ = {isa = PBXBuildFile; productRef = AA00000800000000000000D0 /* URUI */; };
+		3C1E1C462F7B0D99002FDAE2 /* BitcoinDevKit in Frameworks */ = {isa = PBXBuildFile; productRef = 3C1E1C452F7B0D99002FDAE2 /* BitcoinDevKit */; };
+		3C1E1FA52F7B5F63002FDAE2 /* BitcoinDevKit in Frameworks */ = {isa = PBXBuildFile; productRef = 3C1E1FA42F7B5F63002FDAE2 /* BitcoinDevKit */; };
 		AA0000B100000000000000D0 /* Bbqr in Frameworks */ = {isa = PBXBuildFile; productRef = AA0000B000000000000000D0 /* Bbqr */; };
 /* End PBXBuildFile section */
 
@@ -59,9 +60,10 @@
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				3C1E1C462F7B0D99002FDAE2 /* BitcoinDevKit in Frameworks */,
 				3C08EDC12F5E3A8000C2268E /* URUI in Frameworks */,
 				3C08EDC02F5E3A8000C2268E /* URKit in Frameworks */,
-				3C08EDBF2F5E3A8000C2268E /* BitcoinDevKit in Frameworks */,
+				3C1E1FA52F7B5F63002FDAE2 /* BitcoinDevKit in Frameworks */,
 				AA0000B100000000000000D0 /* Bbqr in Frameworks */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
@@ -123,10 +125,11 @@
 			);
 			name = hellbender;
 			packageProductDependencies = (
-				AA00000200000000000000D0 /* BitcoinDevKit */,
 				AA00000500000000000000D0 /* URKit */,
 				AA00000800000000000000D0 /* URUI */,
 				AA0000B000000000000000D0 /* Bbqr */,
+				3C1E1C452F7B0D99002FDAE2 /* BitcoinDevKit */,
+				3C1E1FA42F7B5F63002FDAE2 /* BitcoinDevKit */,
 			);
 			productName = hellbender;
 			productReference = 3C9ACE242F5DED94009B00D0 /* hellbender.app */;
@@ -211,10 +214,10 @@
 			mainGroup = 3C9ACE1B2F5DED94009B00D0;
 			minimizedProjectReferenceProxies = 1;
 			packageReferences = (
-				AA00000100000000000000D0 /* XCRemoteSwiftPackageReference "bdk-swift" */,
 				AA00000400000000000000D0 /* XCRemoteSwiftPackageReference "URKit" */,
 				AA00000700000000000000D0 /* XCRemoteSwiftPackageReference "URUI" */,
 				AA0000A000000000000000D0 /* XCRemoteSwiftPackageReference "bbqr-swift" */,
+				3C1E1FA32F7B5F63002FDAE2 /* XCRemoteSwiftPackageReference "bdk-swift" */,
 			);
 			preferredProjectObjectVersion = 77;
 			productRefGroup = 3C9ACE252F5DED94009B00D0 /* Products */;
@@ -589,12 +592,12 @@
 /* End XCConfigurationList section */
 
 /* Begin XCRemoteSwiftPackageReference section */
-		AA00000100000000000000D0 /* XCRemoteSwiftPackageReference "bdk-swift" */ = {
+		3C1E1FA32F7B5F63002FDAE2 /* XCRemoteSwiftPackageReference "bdk-swift" */ = {
 			isa = XCRemoteSwiftPackageReference;
-			repositoryURL = "https://github.com/bitcoindevkit/bdk-swift";
+			repositoryURL = "https://github.com/newtonick/bdk-swift";
 			requirement = {
 				kind = exactVersion;
-				version = 2.3.1;
+				version = "2.3.1-ssl-patch";
 			};
 		};
 		AA00000400000000000000D0 /* XCRemoteSwiftPackageReference "URKit" */ = {
@@ -624,9 +627,13 @@
 /* End XCRemoteSwiftPackageReference section */
 
 /* Begin XCSwiftPackageProductDependency section */
-		AA00000200000000000000D0 /* BitcoinDevKit */ = {
+		3C1E1C452F7B0D99002FDAE2 /* BitcoinDevKit */ = {
 			isa = XCSwiftPackageProductDependency;
-			package = AA00000100000000000000D0 /* XCRemoteSwiftPackageReference "bdk-swift" */;
+			productName = BitcoinDevKit;
+		};
+		3C1E1FA42F7B5F63002FDAE2 /* BitcoinDevKit */ = {
+			isa = XCSwiftPackageProductDependency;
+			package = 3C1E1FA32F7B5F63002FDAE2 /* XCRemoteSwiftPackageReference "bdk-swift" */;
 			productName = BitcoinDevKit;
 		};
 		AA00000500000000000000D0 /* URKit */ = {

hellbender/Models/WalletProfile.swift

@@ -17,6 +17,7 @@ final class WalletProfile {
   var electrumPort: Int
   var electrumSSL: Int // 0 = network default, 1 = TCP, 2 = SSL
   var blockExplorerHost: String // empty = mempool.space
+  var electrumAllowInsecureSSL: Bool = false
   var privacyMode: Bool = false
 
   @Relationship(deleteRule: .cascade, inverse: \CosignerInfo.wallet)
@@ -35,6 +36,7 @@ final class WalletProfile {
     electrumHost: String = "",
     electrumPort: Int = 0,
     electrumSSL: Int = 0,
+    electrumAllowInsecureSSL: Bool = false,
     blockExplorerHost: String = "",
     privacyMode: Bool = false
   ) {
@@ -51,6 +53,7 @@ final class WalletProfile {
     self.electrumHost = electrumHost
     self.electrumPort = electrumPort
     self.electrumSSL = electrumSSL
+    self.electrumAllowInsecureSSL = electrumAllowInsecureSSL
     self.blockExplorerHost = blockExplorerHost
     self.privacyMode = privacyMode
     cosigners = []
@@ -69,7 +72,7 @@ final class WalletProfile {
     case 2: true // SSL
     default: net.usesSSL // 0 = network default
     }
-    return ElectrumConfig(host: host, port: port, useSSL: ssl)
+    return ElectrumConfig(host: host, port: port, useSSL: ssl, allowInsecureSSL: electrumAllowInsecureSSL)
   }
 
   var multisigDescription: String {

hellbender/Services/BitcoinService.swift

@@ -264,7 +264,8 @@ final class BitcoinService {
     addToLog("Connecting to Electrum: \(config.url)")
     do {
       let url = config.url
-      electrumClient = try await Task.detached { try ElectrumClient(url: url) }.value
+      let validateDomain = !config.allowInsecureSSL
+      electrumClient = try await Task.detached { try ElectrumClient(url: url, validateDomain: validateDomain) }.value
       electrumConnectionError = nil
       addToLog("Electrum client initialized")
     } catch {
@@ -301,7 +302,8 @@ final class BitcoinService {
         let config = profile.electrumConfig
         addToLog("Re-initializing Electrum client: \(config.url)")
         let reconnectURL = config.url
-        electrumClient = try await Task.detached { try ElectrumClient(url: reconnectURL) }.value
+        let validateDomain = !config.allowInsecureSSL
+        electrumClient = try await Task.detached { try ElectrumClient(url: reconnectURL, validateDomain: validateDomain) }.value
         electrumConnectionError = nil
       }
 
@@ -453,13 +455,14 @@ final class BitcoinService {
   @discardableResult
   func testElectrumConnection(config: ElectrumConfig) async throws -> UInt32 {
     // Pre-check SSL certificate before handing off to BDK
-    if config.useSSL {
+    if config.useSSL, !config.allowInsecureSSL {
       try await Self.validateTLSCertificate(host: config.host, port: config.port)
     }
 
     let url = config.url
+    let validateDomain = !config.allowInsecureSSL
     let header = try await Task.detached {
-      let client = try ElectrumClient(url: url)
+      let client = try ElectrumClient(url: url, validateDomain: validateDomain)
       return try client.blockHeadersSubscribe()
     }.value
     return UInt32(header.height)

hellbender/Services/ElectrumConfig.swift

@@ -4,21 +4,24 @@ struct ElectrumConfig: Equatable {
   var host: String
   var port: UInt16
   var useSSL: Bool
+  var allowInsecureSSL: Bool
 
   var url: String {
     let proto = useSSL ? "ssl" : "tcp"
     return "\(proto)://\(host):\(port)"
   }
 
-  init(host: String, port: UInt16, useSSL: Bool) {
+  init(host: String, port: UInt16, useSSL: Bool, allowInsecureSSL: Bool = false) {
     self.host = host
     self.port = port
     self.useSSL = useSSL
+    self.allowInsecureSSL = allowInsecureSSL
   }
 
   init(network: BitcoinNetwork) {
     host = network.defaultElectrumHost ?? ""
     port = network.defaultElectrumPort
     useSSL = network.usesSSL
+    allowInsecureSSL = false
   }
 }

hellbender/ViewModels/SetupWizardViewModel.swift

@@ -50,6 +50,7 @@ final class SetupWizardViewModel {
   var electrumHost: String = ""
   var electrumPort: String = ""
   var electrumSSL: Int = 0 // 0 = network default, 1 = TCP, 2 = SSL
+  var electrumAllowInsecureSSL: Bool = false
 
   /// Returns an error message if the descriptor contains keys that don't match the selected network, nil otherwise.
   var descriptorNetworkMismatchError: String? {
@@ -449,6 +450,7 @@ final class SetupWizardViewModel {
       electrumHost: electrumHost.trimmingCharacters(in: .whitespaces),
       electrumPort: Int(electrumPort) ?? 0,
       electrumSSL: electrumSSL,
+      electrumAllowInsecureSSL: electrumAllowInsecureSSL,
       blockExplorerHost: blockExplorerHost.trimmingCharacters(in: .whitespaces)
     )
 

hellbender/Views/Main/Settings/WalletInfoView.swift

@@ -23,6 +23,7 @@ struct WalletInfoView: View {
   @State private var connectionTestResult: String?
   @State private var blockExplorerText: String = ""
   @State private var initialElectrumConfig: ElectrumConfig?
+  @State private var showInsecureSSLAlert = false
   @State private var showDescriptorQR = false
   @State private var showDeleteConfirmation = false
   @State private var showDescriptorPDF = false
@@ -200,14 +201,37 @@ struct WalletInfoView: View {
                 default: wallet.bitcoinNetwork.usesSSL ? 2 : 1
                 }
               },
-              set: { wallet.electrumSSL = $0 }
+              set: {
+                wallet.electrumSSL = $0
+                if $0 != 2 {
+                  wallet.electrumAllowInsecureSSL = false
+                }
+              }
             )) {
               Text("TCP").tag(1)
               Text("SSL").tag(2)
             }
             .pickerStyle(.segmented)
           }
 
+          if wallet.electrumSSL == 2 || (wallet.electrumSSL == 0 && wallet.bitcoinNetwork.usesSSL) {
+            Toggle(isOn: Binding(
+              get: { wallet.electrumAllowInsecureSSL },
+              set: { newValue in
+                if newValue {
+                  showInsecureSSLAlert = true
+                } else {
+                  wallet.electrumAllowInsecureSSL = false
+                }
+              }
+            )) {
+              Text("Allow insecure SSL")
+                .font(.hbBody(13))
+                .foregroundStyle(Color.hbTextPrimary)
+            }
+            .tint(Color.hbBitcoinOrange)
+          }
+
           if let result = connectionTestResult {
             Text(result)
               .font(.hbBody(13))
@@ -426,6 +450,14 @@ struct WalletInfoView: View {
         }
       }
     }
+    .alert("Allow Insecure SSL?", isPresented: $showInsecureSSLAlert) {
+      Button("Cancel", role: .cancel) {}
+      Button("Allow", role: .destructive) {
+        wallet.electrumAllowInsecureSSL = true
+      }
+    } message: {
+      Text("This removes the requirement to verify that the server is who it claims to be. The connection will still be encrypted, but self-signed, expired, or invalid certificates will be accepted.")
+    }
     .sheet(isPresented: $showEditCosigners) {
       EditCosignersView(wallet: wallet)
     }
@@ -460,6 +492,7 @@ struct WalletInfoView: View {
     wallet.electrumHost = ""
     wallet.electrumPort = 0
     wallet.electrumSSL = 0
+    wallet.electrumAllowInsecureSSL = false
     electrumHostText = ""
     electrumPortText = ""
     connectionTestResult = nil

hellbender/Views/Setup/ElectrumServerSetupSection.swift

@@ -2,6 +2,15 @@ import SwiftUI
 
 struct ElectrumServerSetupSection: View {
   @Bindable var viewModel: SetupWizardViewModel
+  @State private var showInsecureSSLAlert = false
+
+  private var isSSLSelected: Bool {
+    switch viewModel.electrumSSL {
+    case 1: false
+    case 2: true
+    default: viewModel.network.usesSSL
+    }
+  }
 
   var body: some View {
     VStack(spacing: 12) {
@@ -50,7 +59,12 @@ struct ElectrumServerSetupSection: View {
               default: viewModel.network.usesSSL ? 2 : 1
               }
             },
-            set: { viewModel.electrumSSL = $0 }
+            set: {
+              viewModel.electrumSSL = $0
+              if $0 != 2 {
+                viewModel.electrumAllowInsecureSSL = false
+              }
+            }
           )) {
             Text("TCP").tag(1)
             Text("SSL").tag(2)
@@ -59,6 +73,24 @@ struct ElectrumServerSetupSection: View {
         }
       }
 
+      if isSSLSelected {
+        Toggle(isOn: Binding(
+          get: { viewModel.electrumAllowInsecureSSL },
+          set: { newValue in
+            if newValue {
+              showInsecureSSLAlert = true
+            } else {
+              viewModel.electrumAllowInsecureSSL = false
+            }
+          }
+        )) {
+          Text("Allow insecure SSL")
+            .font(.hbBody(13))
+            .foregroundStyle(Color.hbTextPrimary)
+        }
+        .tint(Color.hbBitcoinOrange)
+      }
+
       if viewModel.network.defaultElectrumHost != nil {
         Text("Leave blank to use defaults for \(viewModel.network.displayName)")
           .font(.hbBody(11))
@@ -70,6 +102,14 @@ struct ElectrumServerSetupSection: View {
       }
     }
     .hbCard()
+    .alert("Allow Insecure SSL?", isPresented: $showInsecureSSLAlert) {
+      Button("Cancel", role: .cancel) {}
+      Button("Allow", role: .destructive) {
+        viewModel.electrumAllowInsecureSSL = true
+      }
+    } message: {
+      Text("This removes the requirement to verify that the server is who it claims to be. The connection will still be encrypted, but self-signed, expired, or invalid certificates will be accepted.")
+    }
   }
 }