Merge JoinMarket-Org#1710: maker: allow receiving more money than promised

861c790 maker: allow receiving more money than promised (Matt Whitlock)

Pull request description:

  Fixes: JoinMarket-Org#1709

ACKs for top commit:
  kristapsk:
    cr utACK 861c790

Tree-SHA512: a027817fcc66be01a5c3423f41359d3aa78caedfa5d4dba25ea3dbf3d70e6132f8f8a682610fb35cbdfa5c0802a94b5d15af1f348c9738cf9c2af29fab8c9545

Author: kristapsk

src/jmclient/maker.py

@@ -230,12 +230,12 @@ def verify_unsigned_tx(self, tx, offerinfo):
         for outs in tx.vout:
             if outs.scriptPubKey == cjaddr_script:
                 times_seen_cj_addr += 1
-                if outs.nValue != amount:
-                    return (False, 'Wrong cj_amount. I expect ' + str(amount))
+                if outs.nValue < amount:
+                    return (False, 'Wrong cj_amount. I expect >=' + str(amount))
             if outs.scriptPubKey == changeaddr_script:
                 times_seen_change_addr += 1
-                if outs.nValue != expected_change_value:
-                    return (False, 'wrong change, i expect ' + str(
+                if outs.nValue < expected_change_value:
+                    return (False, 'Wrong change. I expect >=' + str(
                         expected_change_value))
         if times_seen_cj_addr != 1 or times_seen_change_addr != 1:
             fmt = ('cj or change addr not in tx '