From b97c2857e05d8790ec04a46846bb07a989406c9b Mon Sep 17 00:00:00 2001
From: Neil Booth <kyuupichan@gmail.com>
Date: Sun, 10 Jan 2016 12:35:29 +0900
Subject: [PATCH] Fixes for message sign and verify

base64 can throw which caused silent verification failures.
Ask for passwords with correct parent window otherwise dialog
not visible on MacOSX.  Similarly for verification messages.
---
 gui/qt/main_window.py | 32 +++++++++++++++++++++-----------
 1 file changed, 21 insertions(+), 11 deletions(-)

diff --git a/gui/qt/main_window.py b/gui/qt/main_window.py
index 642753c0..5f65068f 100644
--- a/gui/qt/main_window.py
+++ b/gui/qt/main_window.py
@@ -183,6 +183,13 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
         return "%s/%s" % (PrintError.diagnostic_name(self),
                           self.wallet.basename() if self.wallet else "None")
 
+    def top_level_window(self, window=None):
+        window = window or self
+        for n, child in enumerate(window.children()):
+            if isinstance(child, WindowModalDialog):
+                return self.top_level_window(child)
+        return window
+
     def is_hidden(self):
         return self.isMinimized() or self.isHidden()
 
@@ -1133,7 +1140,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
         return value of the wrapped function, or None if cancelled.
         '''
         def request_password(self, *args, **kwargs):
-            parent = kwargs.get('parent', self)
+            parent = kwargs.get('parent', self.top_level_window())
             password = None
             while self.wallet.use_encryption:
                 password = self.password_dialog(parent=parent)
@@ -2065,21 +2072,24 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
     def do_sign(self, address, message, signature, password):
         message = unicode(message.toPlainText())
         message = message.encode('utf-8')
-        try:
-            sig = self.wallet.sign_message(str(address.text()), message, password)
-            sig = base64.b64encode(sig)
-            signature.setText(sig)
-        except Exception as e:
-            self.show_message(str(e))
+        sig = self.wallet.sign_message(str(address.text()), message, password)
+        sig = base64.b64encode(sig)
+        signature.setText(sig)
 
     def do_verify(self, address, message, signature):
         message = unicode(message.toPlainText())
         message = message.encode('utf-8')
-        sig = base64.b64decode(str(signature.toPlainText()))
-        if bitcoin.verify_message(address.text(), sig, message):
-            self.show_message(_("Signature verified"))
+        try:
+            # This can throw on invalid base64
+            sig = base64.b64decode(str(signature.toPlainText()))
+            verified = bitcoin.verify_message(address.text(), sig, message)
+        except:
+            verified = False
+        dialog = self.top_level_window()
+        if verified:
+            dialog.show_message(_("Signature verified"))
         else:
-            self.show_message(_("Error: wrong signature"))
+            dialog.show_error(_("Wrong signature"))
 
 
     def sign_verify_message(self, address=''):