signtx: do not include change in total

src/apps/common/signtx.py

@@ -33,8 +33,8 @@ class UiConfirmOutput:
 
 class UiConfirmTotal:
 
-    def __init__(self, total_out: int, fee: int, coin: CoinType):
-        self.total_out = total_out
+    def __init__(self, spending: int, fee: int, coin: CoinType):
+        self.spending = spending
         self.fee = fee
         self.coin = coin
 
@@ -43,8 +43,8 @@ def confirm_output(output: TxOutputType, coin: CoinType):
     return (yield UiConfirmOutput(output, coin))
 
 
-def confirm_total(total_out: int, fee: int, coin: CoinType):
-    return (yield UiConfirmTotal(total_out, fee, coin))
+def confirm_total(spending: int, fee: int, coin: CoinType):
+    return (yield UiConfirmTotal(spending, fee, coin))
 
 
 def request_tx_meta(tx_req: TxRequest, tx_hash: bytes=None):
@@ -141,7 +141,11 @@ async def sign_tx(tx: SignTx, root):
 
     fee = total_in - total_out
 
-    if not await confirm_total(total_out, fee, coin):
+    if fee < 0:
+        raise SigningError(FailureType.NotEnoughFunds,
+                           'Not enough funds')
+
+    if not await confirm_total(total_out - change_out, fee, coin):
         raise SigningError(FailureType.ActionCancelled,
                            'Total cancelled')
 

src/apps/wallet/layout_sign_tx.py

@@ -20,14 +20,14 @@ async def confirm_output(session_id, output, coin):
     return await confirm(session_id, content, ConfirmOutput)
 
 
-async def confirm_total(session_id, total_out, fee, coin):
+async def confirm_total(session_id, spending, fee, coin):
     from trezor import ui
     from trezor.ui.text import Text
     from trezor.messages.ButtonRequestType import SignTx
     from ..common.confirm import confirm
 
     content = Text('Confirm transaction', ui.ICON_RESET,
-                   'Sending: %s' % format_amount(total_out, coin),
+                   'Sending: %s' % format_amount(spending, coin),
                    'Fee: %s' % format_amount(fee, coin))
     return await confirm(session_id, content, SignTx)
 
@@ -57,7 +57,7 @@ async def layout_sign_tx(message, session_id):
         elif isinstance(req, signtx.UiConfirmOutput):
             res = await confirm_output(session_id, req.output, req.coin)
         elif isinstance(req, signtx.UiConfirmTotal):
-            res = await confirm_total(session_id, req.total_out, req.fee, req.coin)
+            res = await confirm_total(session_id, req.spending, req.fee, req.coin)
         else:
             print(req)
             raise ValueError('Invalid signing instruction')