Cw 565 sign messages (#1378)

* version bump to 3.13.9, auth working on mac

* bump flutter version in workflow file

* workflow fix

* test fix

* downgrade flutter version

* test fix

* test fix

* update gradle version

* start working on ui for message signing

* updates

* sign working for a few wallet types

* updates & verification for electrum currencies

* nano support

* sign/verify working on eth, bitcoin broken

* update translations

* Implement Verify Message for Monero

* save [skip ci]

* pub key extraction working

* fixes for electrum signing

* verify working for solana!

* electrum still not working :( [skip ci]

* electrum messages working!

* fixes for updated dart version, localization file updates

* remove accidental inclusion

* missed some unimplemented throws

* Update res/values/strings_de.arb

Co-authored-by: Konstantin Ullrich <konstantinullrich12@gmail.com>

* Apply suggestions from code review

Co-authored-by: Konstantin Ullrich <konstantinullrich12@gmail.com>

* review suggestions and updates [skip ci]

* [skip ci] add polygon

* [skip ci] merge mac-auth/update version

* fix litecoin

* bio auth mac fix

* remove comment and change duration from 2 to 0

* cherry pick previous changes

* litecoin fixes, sign form fixes, use new walletAddressPicker

* support accounts

* verify messages working for monero

* working sign and verify messages for nano

* electrum signing working [skip ci]

* additional nano fixes

* update translations

* attempt to decode signatures with base64

* workaround for secure storage bug on mac

* bump version to 3.19.5 (because breez will need this version anyways)

* some code cleanup

* some changess didn't get saved

* just documenting the issue [skip ci]

* undo accidental removal + minor code cleanup

* merge conflicts

* merge fixes [skip ci]

* add tron support

* [wip] fixing

* remove duplicate references to electrum path for maintainability

* fixes

* minor fix

* fixes

* undo debug comment

* update migration for all electrum based wallets

* hotfixes

* copy over the rest of the fixes

* minor code cleanup [skip ci]

* updates

* electrum signing workinggit statusgit statusgit statusgit status!

* copy same fixes for litecoin

* litecoin fixes

* add v to litecoin signatures

* fix dependencies

* fix bitcoin_base version

* merge fix

* dep override

* fix conflicts with main

* trial fix for android build

* fixes

* fix

* dep fix, should build

* fix signing for bitcoin cash

* [skip ci] minor code cleanup

* [skip ci] minor code cleanup 2

* forgot wonero, various other fixes

* more fixes

* fix solana (untested)

---------

Co-authored-by: Konstantin Ullrich <konstantinullrich12@gmail.com>
Co-authored-by: Omar Hatem <omarh.ismail1@gmail.com>

cw_bitcoin/lib/electrum_wallet.dart

@@ -42,6 +42,7 @@ import 'package:flutter/foundation.dart';
 import 'package:hive/hive.dart';
 import 'package:mobx/mobx.dart';
 import 'package:rxdart/subjects.dart';
+import 'package:http/http.dart' as http;
 import 'package:sp_scanner/sp_scanner.dart';
 
 part 'electrum_wallet.g.dart';
@@ -132,6 +133,7 @@ abstract class ElectrumWalletBase
   final String? _mnemonic;
 
   Bip32Slip10Secp256k1 get hd => accountHD.childKey(Bip32KeyIndex(0));
+  Bip32Slip10Secp256k1 get sideHd => accountHD.childKey(Bip32KeyIndex(1));
 
   final EncryptionFileUtils encryptionFileUtils;
   final String? passphrase;
@@ -591,7 +593,7 @@ abstract class ElectrumWalletBase
       }
 
       final derivationPath =
-          "${_hardenedDerivationPath(walletInfo.derivationInfo?.derivationPath ?? "m/0'")}"
+          "${_hardenedDerivationPath(walletInfo.derivationInfo?.derivationPath ?? electrum_path)}"
           "/${utx.bitcoinAddressRecord.isHidden ? "1" : "0"}"
           "/${utx.bitcoinAddressRecord.index}";
       publicKeys[address.pubKeyHash()] = PublicKeyWithDerivationPath(pubKeyHex, derivationPath);
@@ -1869,11 +1871,70 @@ abstract class ElectrumWalletBase
         ? walletAddresses.allAddresses.firstWhere((element) => element.address == address).index
         : null;
     final HD = index == null ? hd : hd.childKey(Bip32KeyIndex(index));
-    final priv = ECPrivate.fromWif(
-      WifEncoder.encode(HD.privateKey.raw, netVer: network.wifNetVer),
-      netVersion: network.wifNetVer,
-    );
-    return priv.signMessage(StringUtils.encode(message));
+    final priv = ECPrivate.fromHex(HD.privateKey.privKey.toHex());
+
+    String messagePrefix = '\x18Bitcoin Signed Message:\n';
+    final hexEncoded = priv.signMessage(utf8.encode(message), messagePrefix: messagePrefix);
+    final decodedSig = hex.decode(hexEncoded);
+    return base64Encode(decodedSig);
+  }
+
+  @override
+  Future<bool> verifyMessage(String message, String signature, {String? address = null}) async {
+    if (address == null) {
+      return false;
+    }
+
+    List<int> sigDecodedBytes = [];
+
+    if (signature.endsWith('=')) {
+      sigDecodedBytes = base64.decode(signature);
+    } else {
+      sigDecodedBytes = hex.decode(signature);
+    }
+
+    if (sigDecodedBytes.length != 64 && sigDecodedBytes.length != 65) {
+      throw ArgumentException(
+          "signature must be 64 bytes without recover-id or 65 bytes with recover-id");
+    }
+
+    String messagePrefix = '\x18Bitcoin Signed Message:\n';
+    final messageHash = QuickCrypto.sha256Hash(
+        BitcoinSignerUtils.magicMessage(utf8.encode(message), messagePrefix));
+
+    List<int> correctSignature =
+        sigDecodedBytes.length == 65 ? sigDecodedBytes.sublist(1) : List.from(sigDecodedBytes);
+    List<int> rBytes = correctSignature.sublist(0, 32);
+    List<int> sBytes = correctSignature.sublist(32);
+    final sig = ECDSASignature(BigintUtils.fromBytes(rBytes), BigintUtils.fromBytes(sBytes));
+
+    List<int> possibleRecoverIds = [0, 1];
+
+    final baseAddress = addressTypeFromStr(address, network);
+
+    for (int recoveryId in possibleRecoverIds) {
+      final pubKey = sig.recoverPublicKey(messageHash, Curves.generatorSecp256k1, recoveryId);
+
+      final recoveredPub = ECPublic.fromBytes(pubKey!.toBytes());
+
+      String? recoveredAddress;
+
+      if (baseAddress is P2pkAddress) {
+        recoveredAddress = recoveredPub.toP2pkAddress().toAddress(network);
+      } else if (baseAddress is P2pkhAddress) {
+        recoveredAddress = recoveredPub.toP2pkhAddress().toAddress(network);
+      } else if (baseAddress is P2wshAddress) {
+        recoveredAddress = recoveredPub.toP2wshAddress().toAddress(network);
+      } else if (baseAddress is P2wpkhAddress) {
+        recoveredAddress = recoveredPub.toP2wpkhAddress().toAddress(network);
+      }
+
+      if (recoveredAddress == address) {
+        return true;
+      }
+    }
+
+    return false;
   }
 
   Future<void> _setInitialHeight() async {