privkeys WIF: store in extended WIF internally; export as "txin_type:old_wif"

gui/qt/main_window.py

@@ -2094,8 +2094,6 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
             rds_e = ShowQRTextEdit(text=redeem_script)
             rds_e.addCopyButton(self.app)
             vbox.addWidget(rds_e)
-        if xtype in ['p2wpkh', 'p2wsh', 'p2wpkh-p2sh', 'p2wsh-p2sh']:
-            vbox.addWidget(WWLabel(_("Warning: the format of private keys associated to segwit addresses may not be compatible with other wallets")))
         vbox.addLayout(Buttons(CloseButton(d)))
         d.setLayout(vbox)
         d.exec_()
@@ -2334,7 +2332,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
                               _('It can not be "backed up" by simply exporting these private keys.'))
 
         d = WindowModalDialog(self, _('Private keys'))
-        d.setMinimumSize(850, 300)
+        d.setMinimumSize(980, 300)
         vbox = QVBoxLayout(d)
 
         msg = "%s\n%s\n%s" % (_("WARNING: ALL your private keys are secret."),

gui/qt/util.py

@@ -254,7 +254,7 @@ def line_dialog(parent, title, label, ok_label, default=None):
 def text_dialog(parent, title, label, ok_label, default=None, allow_multi=False):
     from .qrtextedit import ScanQRTextEdit
     dialog = WindowModalDialog(parent, title)
-    dialog.setMinimumWidth(500)
+    dialog.setMinimumWidth(600)
     l = QVBoxLayout()
     dialog.setLayout(l)
     l.addWidget(QLabel(label))

lib/bitcoin.py

@@ -508,9 +508,8 @@ def DecodeBase58Check(psz):
         return key
 
 
-
-# extended key export format for segwit
-
+# backwards compat
+# extended WIF for segwit (used in 3.0.x; but still used internally)
 SCRIPT_TYPES = {
     'p2pkh':0,
     'p2wpkh':1,
@@ -521,26 +520,43 @@ SCRIPT_TYPES = {
 }
 
 
-def serialize_privkey(secret, compressed, txin_type):
-    prefix = bytes([(SCRIPT_TYPES[txin_type]+NetworkConstants.WIF_PREFIX)&255])
+def serialize_privkey(secret, compressed, txin_type, internal_use=False):
+    if internal_use:
+        prefix = bytes([(SCRIPT_TYPES[txin_type] + NetworkConstants.WIF_PREFIX) & 255])
+    else:
+        prefix = bytes([NetworkConstants.WIF_PREFIX])
     suffix = b'\01' if compressed else b''
     vchIn = prefix + secret + suffix
-    return EncodeBase58Check(vchIn)
+    base58_wif = EncodeBase58Check(vchIn)
+    if internal_use:
+        return base58_wif
+    else:
+        return '{}:{}'.format(txin_type, base58_wif)
 
 
 def deserialize_privkey(key):
-    # whether the pubkey is compressed should be visible from the keystore
-    vch = DecodeBase58Check(key)
     if is_minikey(key):
         return 'p2pkh', minikey_to_private_key(key), True
-    elif vch:
-        txin_type = inv_dict(SCRIPT_TYPES)[vch[0] - NetworkConstants.WIF_PREFIX]
-        assert len(vch) in [33, 34]
-        compressed = len(vch) == 34
-        return txin_type, vch[1:33], compressed
-    else:
+
+    txin_type = None
+    if ':' in key:
+        txin_type, key = key.split(sep=':', maxsplit=1)
+        assert txin_type in SCRIPT_TYPES
+    vch = DecodeBase58Check(key)
+    if not vch:
         raise BaseException("cannot deserialize", key)
 
+    if txin_type is None:
+        # keys exported in version 3.0.x encoded script type in first byte
+        txin_type = inv_dict(SCRIPT_TYPES)[vch[0] - NetworkConstants.WIF_PREFIX]
+    else:
+        assert vch[0] == NetworkConstants.WIF_PREFIX
+
+    assert len(vch) in [33, 34]
+    compressed = len(vch) == 34
+    return txin_type, vch[1:33], compressed
+
+
 def regenerate_key(pk):
     assert len(pk) == 32
     return EC_KEY(pk)

lib/keystore.py

@@ -139,7 +139,10 @@ class Imported_KeyStore(Software_KeyStore):
     def import_privkey(self, sec, password):
         txin_type, privkey, compressed = deserialize_privkey(sec)
         pubkey = public_key_from_private_key(privkey, compressed)
-        self.keypairs[pubkey] = pw_encode(sec, password)
+        # re-serialize the key so the internal storage format is consistent
+        serialized_privkey = serialize_privkey(
+            privkey, compressed, txin_type, internal_use=True)
+        self.keypairs[pubkey] = pw_encode(serialized_privkey, password)
         return txin_type, pubkey
 
     def delete_imported_key(self, key):

lib/wallet.py

@@ -388,23 +388,21 @@ class Abstract_Wallet(PrintError):
     def get_address_index(self, address):
         raise NotImplementedError()
 
+    def get_redeem_script(self, address):
+        return None
+
     def export_private_key(self, address, password):
-        """ extended WIF format """
         if self.is_watching_only():
             return []
         index = self.get_address_index(address)
         pk, compressed = self.keystore.get_private_key(index, password)
-        if self.txin_type in ['p2sh', 'p2wsh', 'p2wsh-p2sh']:
-            pubkeys = self.get_public_keys(address)
-            redeem_script = self.pubkeys_to_redeem_script(pubkeys)
-        else:
-            redeem_script = None
-        return bitcoin.serialize_privkey(pk, compressed, self.txin_type), redeem_script
-
+        txin_type = self.get_txin_type(address)
+        redeem_script = self.get_redeem_script(address)
+        serialized_privkey = bitcoin.serialize_privkey(pk, compressed, txin_type)
+        return serialized_privkey, redeem_script
 
     def get_public_keys(self, address):
-        sequence = self.get_address_index(address)
-        return self.get_pubkeys(*sequence)
+        return [self.get_public_key(address)]
 
     def add_unverified_tx(self, tx_hash, tx_height):
         if tx_height in (TX_HEIGHT_UNCONFIRMED, TX_HEIGHT_UNCONF_PARENT) \
@@ -1896,12 +1894,10 @@ class Imported_Wallet(Simple_Wallet):
         self.add_address(addr)
         return addr
 
-    def export_private_key(self, address, password):
+    def get_redeem_script(self, address):
         d = self.addresses[address]
-        pubkey = d['pubkey']
         redeem_script = d['redeem_script']
-        sec = pw_decode(self.keystore.keypairs[pubkey], password)
-        return sec, redeem_script
+        return redeem_script
 
     def get_txin_type(self, address):
         return self.addresses[address].get('type', 'address')
@@ -2079,9 +2075,6 @@ class Simple_Deterministic_Wallet(Simple_Wallet, Deterministic_Wallet):
     def get_pubkey(self, c, i):
         return self.derive_pubkeys(c, i)
 
-    def get_public_keys(self, address):
-        return [self.get_public_key(address)]
-
     def add_input_sig_info(self, txin, address):
         derivation = self.get_address_index(address)
         x_pubkey = self.keystore.get_xpubkey(*derivation)
@@ -2119,6 +2112,10 @@ class Multisig_Wallet(Deterministic_Wallet):
     def get_pubkeys(self, c, i):
         return self.derive_pubkeys(c, i)
 
+    def get_public_keys(self, address):
+        sequence = self.get_address_index(address)
+        return self.get_pubkeys(*sequence)
+
     def pubkeys_to_address(self, pubkeys):
         redeem_script = self.pubkeys_to_redeem_script(pubkeys)
         return bitcoin.redeem_script_to_address(self.txin_type, redeem_script)
@@ -2126,6 +2123,11 @@ class Multisig_Wallet(Deterministic_Wallet):
     def pubkeys_to_redeem_script(self, pubkeys):
         return transaction.multisig_script(sorted(pubkeys), self.m)
 
+    def get_redeem_script(self, address):
+        pubkeys = self.get_public_keys(address)
+        redeem_script = self.pubkeys_to_redeem_script(pubkeys)
+        return redeem_script
+
     def derive_pubkeys(self, c, i):
         return [k.derive_pubkey(c, i) for k in self.get_keystores()]