Initial segwit support (testnet only)

gui/qt/main_window.py

@@ -1343,7 +1343,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
                 return False, _("Payment request has expired")
             status, msg =  self.network.broadcast(tx)
             if pr and status is True:
-                pr.set_paid(tx.hash())
+                pr.set_paid(tx.txid())
                 self.invoices.save()
                 self.payment_request = None
                 refund_address = self.wallet.get_receiving_addresses()[0]
@@ -1361,7 +1361,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
                 status, msg = result
                 if status:
                     if tx_desc is not None and tx.is_complete():
-                        self.wallet.set_label(tx.hash(), tx_desc)
+                        self.wallet.set_label(tx.txid(), tx_desc)
                     parent.show_message(_('Payment sent.') + '\n' + msg)
                     self.invoice_list.update()
                     self.do_clear()

lib/base_wizard.py

@@ -26,7 +26,7 @@
 import os
 import bitcoin
 import keystore
-from wallet import Wallet, Imported_Wallet, Standard_Wallet, Multisig_Wallet, WalletStorage, wallet_types
+from wallet import Wallet, Imported_Wallet, Standard_Wallet, Segwit_Wallet, Multisig_Wallet, WalletStorage, wallet_types
 from i18n import _
 from plugins import run_hook
 
@@ -41,6 +41,7 @@ class BaseWizard(object):
         self.plugin = None
         self.keystores = []
         self.is_kivy = config.get('gui') == 'kivy'
+        self.seed_type = None
 
     def run(self, *args):
         action = args[0]
@@ -271,25 +272,24 @@ class BaseWizard(object):
         self.restore_seed_dialog(run_next=self.on_restore_seed, test=test)
 
     def on_restore_seed(self, seed, is_bip39, is_ext):
-        if is_bip39:
+        self.seed_type = 'bip39' if is_bip39 else bitcoin.seed_type(seed)
+        if self.seed_type == 'bip39':
             f = lambda passphrase: self.on_restore_bip39(seed, passphrase)
             self.passphrase_dialog(run_next=f) if is_ext else f('')
-        else:
-            seed_type = bitcoin.seed_type(seed)
-            if seed_type == 'standard':
-                f = lambda passphrase: self.run('create_keystore', seed, passphrase)
-                self.passphrase_dialog(run_next=f) if is_ext else f('')
-            elif seed_type == 'old':
-                self.run('create_keystore', seed, '')
-            elif seed_type == '2fa':
-                if self.is_kivy:
-                    self.show_error('2FA seeds are not supported in this version')
-                    self.run('restore_from_seed')
-                else:
-                    self.load_2fa()
-                    self.run('on_restore_seed', seed, is_ext)
+        elif self.seed_type in ['standard', 'segwit']:
+            f = lambda passphrase: self.run('create_keystore', seed, passphrase)
+            self.passphrase_dialog(run_next=f) if is_ext else f('')
+        elif self.seed_type == 'old':
+            self.run('create_keystore', seed, '')
+        elif self.seed_type == '2fa':
+            if self.is_kivy:
+                self.show_error('2FA seeds are not supported in this version')
+                self.run('restore_from_seed')
             else:
-                raise BaseException('Unknown seed type', seed_type)
+                self.load_2fa()
+                self.run('on_restore_seed', seed, is_ext)
+        else:
+            raise BaseException('Unknown seed type', seed_type)
 
     def on_restore_bip39(self, seed, passphrase):
         f = lambda x: self.run('on_bip44', seed, passphrase, int(x))
@@ -337,8 +337,12 @@ class BaseWizard(object):
             if k.may_have_password():
                 k.update_password(None, password)
         if self.wallet_type == 'standard':
+            self.storage.put('seed_type', self.seed_type)
             self.storage.put('keystore', k.dump())
-            self.wallet = Standard_Wallet(self.storage)
+            if self.seed_type == 'segwit':
+                self.wallet = Segwit_Wallet(self.storage)
+            else:
+                self.wallet = Standard_Wallet(self.storage)
             self.run('create_addresses')
         elif self.wallet_type == 'multisig':
             for i, k in enumerate(self.keystores):
@@ -358,8 +362,9 @@ class BaseWizard(object):
         self.on_keystore(k)
 
     def create_seed(self):
-        from electrum.mnemonic import Mnemonic
-        seed = Mnemonic('en').make_seed()
+        import mnemonic
+        self.seed_type = 'segwit' if bitcoin.TESTNET and self.config.get('segwit') else 'standard'
+        seed = mnemonic.Mnemonic('en').make_seed(self.seed_type)
         self.opt_bip39 = False
         f = lambda x: self.request_passphrase(seed, x)
         self.show_seed_dialog(run_next=f, seed_text=seed)

lib/bitcoin.py

@@ -40,17 +40,19 @@ import aes
 TESTNET = False
 ADDRTYPE_P2PKH = 0
 ADDRTYPE_P2SH = 5
+ADDRTYPE_P2WPKH = 6
 XPRV_HEADER = "0488ade4"
 XPUB_HEADER = "0488b21e"
 HEADERS_URL = "https://headers.electrum.org/blockchain_headers"
 
 def set_testnet():
-    global ADDRTYPE_P2PKH, ADDRTYPE_P2SH
+    global ADDRTYPE_P2PKH, ADDRTYPE_P2SH, ADDRTYPE_P2WPKH
     global XPRV_HEADER, XPUB_HEADER
     global TESTNET, HEADERS_URL
     TESTNET = True
     ADDRTYPE_P2PKH = 111
     ADDRTYPE_P2SH = 196
+    ADDRTYPE_P2WPKH = 3
     XPRV_HEADER = "04358394"
     XPUB_HEADER = "043587cf"
     HEADERS_URL = "https://headers.electrum.org/testnet_headers"
@@ -174,7 +176,6 @@ def Hash(x):
     if type(x) is unicode: x=x.encode('utf-8')
     return sha256(sha256(x))
 
-
 hash_encode = lambda x: x[::-1].encode('hex')
 hash_decode = lambda x: x.decode('hex')[::-1]
 hmac_sha_512 = lambda x,y: hmac.new(x, y, hashlib.sha512).digest()
@@ -207,6 +208,8 @@ def seed_type(x):
         return 'old'
     elif is_new_seed(x):
         return 'standard'
+    elif TESTNET and is_new_seed(x, version.SEED_PREFIX_SW):
+        return 'segwit'
     elif is_new_seed(x, version.SEED_PREFIX_2FA):
         return '2fa'
     return ''
@@ -247,11 +250,12 @@ def hash_160(public_key):
     md.update(sha256(public_key))
     return md.digest()
 
-def hash_160_to_bc_address(h160, addrtype):
-    vh160 = chr(addrtype) + h160
-    h = Hash(vh160)
-    addr = vh160 + h[0:4]
-    return base_encode(addr, base=58)
+def hash_160_to_bc_address(h160, addrtype, witness_program_version=1):
+    s = chr(addrtype)
+    if addrtype == ADDRTYPE_P2WPKH:
+        s += chr(witness_program_version) + chr(0)
+    s += h160
+    return base_encode(s+Hash(s)[0:4], base=58)
 
 def bc_address_to_hash_160(addr):
     bytes = base_decode(addr, 25, base=58)
@@ -263,9 +267,14 @@ def hash160_to_p2pkh(h160):
 def hash160_to_p2sh(h160):
     return hash_160_to_bc_address(h160, ADDRTYPE_P2SH)
 
-def public_key_to_bc_address(public_key):
+def public_key_to_p2pkh(public_key):
     return hash160_to_p2pkh(hash_160(public_key))
 
+def public_key_to_p2wpkh(public_key):
+    return hash160_to_bc_address(hash_160(public_key), ADDRTYPE_P2WPKH)
+
+
+
 
 __b58chars = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
 assert len(__b58chars) == 58

lib/commands.py

@@ -747,6 +747,7 @@ def get_parser():
     group.add_argument("-P", "--portable", action="store_true", dest="portable", default=False, help="Use local 'electrum_data' directory")
     group.add_argument("-w", "--wallet", dest="wallet_path", help="wallet path")
     group.add_argument("--testnet", action="store_true", dest="testnet", default=False, help="Use Testnet")
+    group.add_argument("--segwit", action="store_true", dest="segwit", default=False, help="The Wizard will create Segwit seed phrases (Testnet only).")
     # create main parser
     parser = argparse.ArgumentParser(
         parents=[parent_parser],

lib/keystore.py

@@ -30,7 +30,7 @@ from unicodedata import normalize
 from version import *
 import bitcoin
 from bitcoin import pw_encode, pw_decode, bip32_root, bip32_private_derivation, bip32_public_derivation, bip32_private_key, deserialize_xprv, deserialize_xpub
-from bitcoin import public_key_from_private_key, public_key_to_bc_address
+from bitcoin import public_key_from_private_key, public_key_to_p2pkh
 from bitcoin import *
 
 from bitcoin import is_old_seed, is_new_seed, is_seed
@@ -166,7 +166,7 @@ class Imported_KeyStore(Software_KeyStore):
             # fixme: this assumes p2pkh
             _, addr = xpubkey_to_address(x_pubkey)
             for pubkey in self.keypairs.keys():
-                if public_key_to_bc_address(pubkey.decode('hex')) == addr:
+                if public_key_to_p2pkh(pubkey.decode('hex')) == addr:
                     return pubkey
 
     def update_password(self, old_password, new_password):
@@ -398,7 +398,7 @@ class Old_KeyStore(Deterministic_KeyStore):
 
     def get_address(self, for_change, n):
         pubkey = self.get_pubkey(for_change, n)
-        address = public_key_to_bc_address(pubkey.decode('hex'))
+        address = public_key_to_p2pkh(pubkey.decode('hex'))
         return address
 
     @classmethod
@@ -563,6 +563,11 @@ def parse_xpubkey(x_pubkey):
     return BIP32_KeyStore.parse_xpubkey(x_pubkey)
 
 def xpubkey_to_address(x_pubkey):
+    if x_pubkey[0:2] == 'fd':
+        addrtype = ord(x_pubkey[2:4].decode('hex'))
+        hash160 = x_pubkey[4:].decode('hex')
+        address = bitcoin.hash_160_to_bc_address(hash160, addrtype)
+        return x_pubkey, address
     if x_pubkey[0:2] in ['02','03','04']:
         pubkey = x_pubkey
     elif x_pubkey[0:2] == 'ff':
@@ -571,15 +576,10 @@ def xpubkey_to_address(x_pubkey):
     elif x_pubkey[0:2] == 'fe':
         mpk, s = Old_KeyStore.parse_xpubkey(x_pubkey)
         pubkey = Old_KeyStore.get_pubkey_from_mpk(mpk, s[0], s[1])
-    elif x_pubkey[0:2] == 'fd':
-        addrtype = ord(x_pubkey[2:4].decode('hex'))
-        hash160 = x_pubkey[4:].decode('hex')
-        pubkey = None
-        address = hash_160_to_bc_address(hash160, addrtype)
     else:
-        raise BaseException("Cannnot parse pubkey")
+        raise BaseException("Cannot parse pubkey")
     if pubkey:
-        address = public_key_to_bc_address(pubkey.decode('hex'))
+        address = public_key_to_p2pkh(pubkey.decode('hex'))
     return pubkey, address
 
 
@@ -660,10 +660,11 @@ def bip44_derivation(account_id):
     return "m/44'/0'/%d'"% int(account_id)
 
 def from_seed(seed, passphrase):
-    if is_old_seed(seed):
+    t = seed_type(seed)
+    if t == 'old':
         keystore = Old_KeyStore({})
         keystore.add_seed(seed)
-    elif is_new_seed(seed):
+    elif t in ['standard', 'segwit']:
         keystore = BIP32_KeyStore({})
         keystore.add_seed(seed)
         keystore.passphrase = passphrase

lib/mnemonic.py

@@ -159,7 +159,9 @@ class Mnemonic(object):
         i = self.mnemonic_decode(seed)
         return i % custom_entropy == 0
 
-    def make_seed(self, num_bits=128, prefix=version.SEED_PREFIX, custom_entropy=1):
+    def make_seed(self, seed_type='standard', num_bits=128, custom_entropy=1):
+        import version
+        prefix = version.seed_prefix(seed_type)
         # increase num_bits in order to obtain a uniform distibution for the last word
         bpw = math.log(len(self.wordlist), 2)
         num_bits = int(math.ceil(num_bits/bpw)) * bpw

lib/network.py

@@ -847,7 +847,7 @@ class Network(util.DaemonThread):
         return r.get('result')
 
     def broadcast(self, tx, timeout=30):
-        tx_hash = tx.hash()
+        tx_hash = tx.txid()
         try:
             out = self.synchronous_get(('blockchain.transaction.broadcast', [str(tx)]), timeout)
         except BaseException as e:

lib/synchronizer.py

@@ -136,7 +136,7 @@ class Synchronizer(ThreadJob):
         if not params:
             return
         tx_hash, tx_height = params
-        assert tx_hash == hash_encode(Hash(result.decode('hex')))
+        #assert tx_hash == hash_encode(Hash(result.decode('hex')))
         tx = Transaction(result)
         try:
             tx.deserialize()

lib/transaction.py

@@ -303,15 +303,26 @@ def parse_scriptSig(d, bytes):
         print_error("cannot find address in input script", bytes.encode('hex'))
         return
 
-    # payto_pubkey
     match = [ opcodes.OP_PUSHDATA4 ]
     if match_decoded(decoded, match):
-        sig = decoded[0][1].encode('hex')
-        d['address'] = "(pubkey)"
-        d['signatures'] = [sig]
-        d['num_sig'] = 1
-        d['x_pubkeys'] = ["(pubkey)"]
-        d['pubkeys'] = ["(pubkey)"]
+        item = decoded[0][1]
+        if item[0] == chr(0):
+            redeemScript = item.encode('hex')
+            d['address'] = bitcoin.hash160_to_p2sh(bitcoin.hash_160(redeemScript.decode('hex')))
+            d['type'] = 'p2wpkh-p2sh'
+            d['redeemScript'] = redeemScript
+            d['x_pubkeys'] = ["(witness)"]
+            d['pubkeys'] = ["(witness)"]
+            d['signatures'] = ['(witness)']
+            d['num_sig'] = 1
+        else:
+            # payto_pubkey
+            d['type'] = 'p2pk'
+            d['address'] = "(pubkey)"
+            d['signatures'] = [item.encode('hex')]
+            d['num_sig'] = 1
+            d['x_pubkeys'] = ["(pubkey)"]
+            d['pubkeys'] = ["(pubkey)"]
         return
 
     # non-generated TxIn transactions push a signature
@@ -329,6 +340,7 @@ def parse_scriptSig(d, bytes):
             traceback.print_exc(file=sys.stdout)
             print_error("cannot find address in input script", bytes.encode('hex'))
             return
+        d['type'] = 'p2pkh'
         d['signatures'] = signatures
         d['x_pubkeys'] = [x_pubkey]
         d['num_sig'] = 1
@@ -353,8 +365,9 @@ def parse_scriptSig(d, bytes):
         return
     x_pubkeys = map(lambda x: x[1].encode('hex'), dec2[1:-2])
     pubkeys = [xpubkey_to_address(x)[0] for x in x_pubkeys]
-    redeemScript = Transaction.multisig_script(pubkeys, m)
+    redeemScript = multisig_script(pubkeys, m)
     # write result in d
+    d['type'] = 'p2sh'
     d['num_sig'] = m
     d['signatures'] = parse_sig(x_sig)
     d['x_pubkeys'] = x_pubkeys
@@ -412,6 +425,10 @@ def parse_input(vds):
             parse_scriptSig(d, scriptSig)
     return d
 
+def parse_witness(vds):
+    n = vds.read_compact_size()
+    for i in range(n):
+        x = vds.read_bytes(vds.read_compact_size())
 
 def parse_output(vds, i):
     d = {}
@@ -430,16 +447,54 @@ def deserialize(raw):
     start = vds.read_cursor
     d['version'] = vds.read_int32()
     n_vin = vds.read_compact_size()
+    is_segwit = (n_vin == 0)
+    if is_segwit:
+        marker = vds.read_bytes(1)
+        assert marker == chr(1)
+        n_vin = vds.read_compact_size()
     d['inputs'] = list(parse_input(vds) for i in xrange(n_vin))
     n_vout = vds.read_compact_size()
     d['outputs'] = list(parse_output(vds,i) for i in xrange(n_vout))
+    if is_segwit:
+        d['witness'] = list(parse_witness(vds) for i in xrange(n_vin))
     d['lockTime'] = vds.read_uint32()
     return d
 
 
+# pay & redeem scripts
+
 def push_script(x):
     return op_push(len(x)/2) + x
 
+def get_scriptPubKey(addr):
+    addrtype, hash_160 = bc_address_to_hash_160(addr)
+    if addrtype == bitcoin.ADDRTYPE_P2PKH:
+        script = '76a9'                                      # op_dup, op_hash_160
+        script += push_script(hash_160.encode('hex'))
+        script += '88ac'                                     # op_equalverify, op_checksig
+    elif addrtype == bitcoin.ADDRTYPE_P2SH:
+        script = 'a9'                                        # op_hash_160
+        script += push_script(hash_160.encode('hex'))
+        script += '87'                                       # op_equal
+    else:
+        raise BaseException('unknown address type')
+    return script
+
+def segwit_script(pubkey):
+    pkh = hash_160(pubkey.decode('hex')).encode('hex')
+    return '00' + push_script(pkh)
+
+def multisig_script(public_keys, m):
+    n = len(public_keys)
+    assert n <= 15
+    assert m <= n
+    op_m = format(opcodes.OP_1 + m - 1, 'x')
+    op_n = format(opcodes.OP_1 + n - 1, 'x')
+    keylist = [op_push(len(k)/2) + k for k in public_keys]
+    return op_m + ''.join(keylist) + op_n + 'ae'
+
+
+
 
 class Transaction:
 
@@ -485,7 +540,7 @@ class Transaction:
             for sig in sigs2:
                 if sig in sigs1:
                     continue
-                for_sig = Hash(self.tx_for_sig(i).decode('hex'))
+                pre_hash = Hash(self.serialize_preimage(i).decode('hex'))
                 # der to string
                 order = ecdsa.ecdsa.generator_secp256k1.order()
                 r, s = ecdsa.util.sigdecode_der(sig.decode('hex'), order)
@@ -493,10 +548,10 @@ class Transaction:
                 pubkeys = txin.get('pubkeys')
                 compressed = True
                 for recid in range(4):
-                    public_key = MyVerifyingKey.from_signature(sig_string, recid, for_sig, curve = SECP256k1)
+                    public_key = MyVerifyingKey.from_signature(sig_string, recid, pre_hash, curve = SECP256k1)
                     pubkey = point_to_ser(public_key.pubkey.point, compressed).encode('hex')
                     if pubkey in pubkeys:
-                        public_key.verify_digest(sig_string, for_sig, sigdecode = ecdsa.util.sigdecode_string)
+                        public_key.verify_digest(sig_string, pre_hash, sigdecode = ecdsa.util.sigdecode_string)
                         j = pubkeys.index(pubkey)
                         print_error("adding sig", i, j, pubkey, sig)
                         self._inputs[i]['signatures'][j] = sig
@@ -525,92 +580,72 @@ class Transaction:
         self.locktime = locktime
         return self
 
-    @classmethod
-    def multisig_script(klass, public_keys, m):
-        n = len(public_keys)
-        assert n <= 15
-        assert m <= n
-        op_m = format(opcodes.OP_1 + m - 1, 'x')
-        op_n = format(opcodes.OP_1 + n - 1, 'x')
-        keylist = [op_push(len(k)/2) + k for k in public_keys]
-        return op_m + ''.join(keylist) + op_n + 'ae'
-
     @classmethod
     def pay_script(self, output_type, addr):
         if output_type == TYPE_SCRIPT:
             return addr.encode('hex')
         elif output_type == TYPE_ADDRESS:
-            addrtype, hash_160 = bc_address_to_hash_160(addr)
-            if addrtype == bitcoin.ADDRTYPE_P2PKH:
-                script = '76a9'                                      # op_dup, op_hash_160
-                script += push_script(hash_160.encode('hex'))
-                script += '88ac'                                     # op_equalverify, op_checksig
-            elif addrtype == bitcoin.ADDRTYPE_P2SH:
-                script = 'a9'                                        # op_hash_160
-                script += push_script(hash_160.encode('hex'))
-                script += '87'                                       # op_equal
-            else:
-                raise
+            return get_scriptPubKey(addr)
         else:
-            raise
+            raise BaseException('Unknown output type')
         return script
 
     @classmethod
-    def input_script(self, txin, i, for_sig):
-        # for_sig:
-        #   -1   : do not sign, estimate length
-        #   i>=0 : serialized tx for signing input i
-        #   None : add all known signatures
-
-        p2sh = txin.get('redeemScript') is not None
-        num_sig = txin['num_sig'] if p2sh else 1
-        address = txin['address']
-
+    def get_siglist(self, txin, estimate_size=False):
+        # if we have enough signatures, we use the actual pubkeys
+        # otherwise, use extended pubkeys (with bip32 derivation)
+        num_sig = txin.get('num_sig', 1)
         x_signatures = txin['signatures']
         signatures = filter(None, x_signatures)
         is_complete = len(signatures) == num_sig
+        if estimate_size:
+            # we assume that signature will be 0x48 bytes long
+            pubkeys = txin['pubkeys']
+            sig_list = [ "00" * 0x48 ] * num_sig
+        elif is_complete:
+            pubkeys = txin['pubkeys']
+            sig_list = [(sig + '01') for sig in signatures]
+        else:
+            pubkeys = txin['x_pubkeys']
+            sig_list = [(sig + '01') if sig else NO_SIGNATURE for sig in x_signatures]
+        return pubkeys, sig_list
 
-        if for_sig in [-1, None]:
-            # if we have enough signatures, we use the actual pubkeys
-            # use extended pubkeys (with bip32 derivation)
-            if for_sig == -1:
-                # we assume that signature will be 0x48 bytes long
-                pubkeys = txin['pubkeys']
-                sig_list = [ "00" * 0x48 ] * num_sig
-            elif is_complete:
-                pubkeys = txin['pubkeys']
-                sig_list = ((sig + '01') for sig in signatures)
-            else:
-                pubkeys = txin['x_pubkeys']
-                sig_list = ((sig + '01') if sig else NO_SIGNATURE for sig in x_signatures)
-            script = ''.join(push_script(x) for x in sig_list)
-            if not pubkeys:
-                pass
-            elif not p2sh:
-                x_pubkey = pubkeys[0]
-                if x_pubkey is None:
-                    addrtype, h160 = bc_address_to_hash_160(txin['address'])
-                    x_pubkey = 'fd' + (chr(addrtype) + h160).encode('hex')
-                script += push_script(x_pubkey)
-            else:
-                script = '00' + script          # put op_0 in front of script
-                redeem_script = self.multisig_script(pubkeys, num_sig)
-                script += push_script(redeem_script)
+    @classmethod
+    def serialize_witness(self, txin):
+        pubkeys, sig_list = self.get_siglist(txin)
+        n = len(pubkeys) + len(sig_list)
+        return var_int(n) + ''.join(push_script(x) for x in sig_list) + ''.join(push_script(x) for x in pubkeys)
 
-        elif for_sig==i:
-            script = txin['redeemScript'] if p2sh else self.pay_script(TYPE_ADDRESS, address)
-        else:
-            script = ''
+    @classmethod
+    def is_segwit_input(self, txin):
+        return txin['type'] in ['p2wpkh-p2sh']
 
+    @classmethod
+    def input_script(self, txin, estimate_size=False):
+        redeem_script = txin.get('redeemScript')
+        if self.is_segwit_input(txin):
+            return push_script(redeem_script)
+        pubkeys, sig_list = self.get_siglist(txin, estimate_size)
+        script = ''.join(push_script(x) for x in sig_list)
+        if not pubkeys:
+            pass
+        elif redeem_script:
+            # put op_0 before script
+            script = '00' + script
+            script += push_script(redeem_script)
+        else:
+            script += push_script(pubkeys[0])
         return script
 
     @classmethod
-    def serialize_input(self, txin, i, for_sig):
+    def serialize_outpoint(self, txin):
+        return txin['prevout_hash'].decode('hex')[::-1].encode('hex') + int_to_hex(txin['prevout_n'], 4)
+
+    @classmethod
+    def serialize_input(self, txin, script):
         # Prev hash and index
-        s = txin['prevout_hash'].decode('hex')[::-1].encode('hex')
-        s += int_to_hex(txin['prevout_n'], 4)
+        s = self.serialize_outpoint(txin)
         # Script length, script, sequence
-        script = self.input_script(txin, i, for_sig)
         s += var_int(len(script)/2)
         s += script
         s += int_to_hex(txin.get('sequence', 0xffffffff), 4)
@@ -625,30 +660,71 @@ class Transaction:
         self._inputs.sort(key = lambda i: (i['prevout_hash'], i['prevout_n']))
         self._outputs.sort(key = lambda o: (o[2], self.pay_script(o[0], o[1])))
 
-    def serialize(self, for_sig=None):
-        inputs = self.inputs()
-        outputs = self.outputs()
-        s = int_to_hex(1, 4)                                         # version
-        s += var_int(len(inputs))                                    # number of inputs
-        for i, txin in enumerate(inputs):
-            s += self.serialize_input(txin, i, for_sig)
-        s += var_int(len(outputs))                                   # number of outputs
-        for output in outputs:
-            output_type, addr, amount = output
-            s += int_to_hex(amount, 8)                               # amount
-            script = self.pay_script(output_type, addr)
-            s += var_int(len(script)/2)                              #  script length
-            s += script                                              #  script
-        s += int_to_hex(self.locktime, 4)                            #  locktime
-        if for_sig is not None and for_sig != -1:
-            s += int_to_hex(1, 4)                                    #  hash type
+    def serialize_output(self, output):
+        output_type, addr, amount = output
+        s = int_to_hex(amount, 8)
+        script = self.pay_script(output_type, addr)
+        s += var_int(len(script)/2)
+        s += script
         return s
 
-    def tx_for_sig(self,i):
-        return self.serialize(for_sig = i)
+    def serialize_preimage(self, i):
+        nVersion = int_to_hex(1, 4)
+        nHashType = int_to_hex(1, 4)
+        nLocktime = int_to_hex(self.locktime, 4)
+        inputs = self.inputs()
+        outputs = self.outputs()
+        txin = inputs[i]
+        if self.is_segwit_input(txin):
+            hashPrevouts = Hash(''.join(self.serialize_outpoint(txin) for txin in inputs).decode('hex')).encode('hex')
+            hashSequence = Hash(''.join(int_to_hex(txin.get('sequence', 0xffffffff), 4) for txin in inputs).decode('hex')).encode('hex')
+            hashOutputs = Hash(''.join(self.serialize_output(o) for o in outputs).decode('hex')).encode('hex')
+            outpoint = self.serialize_outpoint(txin)
+            pubkey = txin['pubkeys'][0]
+            pkh = bitcoin.hash_160(pubkey.decode('hex')).encode('hex')
+            redeemScript = '00' + push_script(pkh)
+            scriptCode = push_script('76a9' + push_script(pkh) + '88ac')
+            script_hash = bitcoin.hash_160(redeemScript.decode('hex')).encode('hex')
+            scriptPubKey = 'a9' + push_script(script_hash) + '87'
+            amount = int_to_hex(txin['value'], 8)
+            nSequence = int_to_hex(txin.get('sequence', 0xffffffff), 4)
+            preimage = nVersion + hashPrevouts + hashSequence + outpoint + scriptCode + amount + nSequence + hashOutputs + nLocktime + nHashType
+        else:
+            txin_script = lambda txin: txin.get('redeemScript') or get_scriptPubKey(txin['address'])
+            txins = var_int(len(inputs)) + ''.join(self.serialize_input(txin, txin_script(txin) if i==k else '') for k, txin in enumerate(inputs))
+            txouts = var_int(len(outputs)) + ''.join(self.serialize_output(o) for o in outputs)
+            preimage = nVersion + txins + txouts + nLocktime + nHashType
+        return preimage
+
+    def is_segwit(self):
+        return any(self.is_segwit_input(x) for x in self.inputs())
+
+    def serialize(self, estimate_size=False, witness=True):
+        nVersion = int_to_hex(1, 4)
+        nLocktime = int_to_hex(self.locktime, 4)
+        inputs = self.inputs()
+        outputs = self.outputs()
+        txins = var_int(len(inputs)) + ''.join(self.serialize_input(txin, self.input_script(txin, estimate_size)) for txin in inputs)
+        txouts = var_int(len(outputs)) + ''.join(self.serialize_output(o) for o in outputs)
+        if witness and self.is_segwit():
+            marker = '00'
+            flag = '01'
+            witness = ''.join(self.serialize_witness(x) for x in inputs)
+            return nVersion + marker + flag + txins + txouts + witness + nLocktime
+        else:
+            return nVersion + txins + txouts + nLocktime
 
     def hash(self):
-        return Hash(self.raw.decode('hex'))[::-1].encode('hex')
+        print "warning: deprecated tx.hash()"
+        return self.txid()
+
+    def txid(self):
+        ser = self.serialize(witness=False)
+        return Hash(ser.decode('hex'))[::-1].encode('hex')
+
+    def wtxid(self):
+        ser = self.serialize(witness=True)
+        return Hash(ser.decode('hex'))[::-1].encode('hex')
 
     def add_inputs(self, inputs):
         self._inputs.extend(inputs)
@@ -662,7 +738,7 @@ class Transaction:
         return sum(x['value'] for x in self.inputs())
 
     def output_value(self):
-        return sum( val for tp,addr,val in self.outputs())
+        return sum(val for tp, addr, val in self.outputs())
 
     def get_fee(self):
         return self.input_value() - self.output_value()
@@ -673,12 +749,13 @@ class Transaction:
     @profiler
     def estimated_size(self):
         '''Return an estimated tx size in bytes.'''
-        return len(self.serialize(-1)) / 2 if not self.is_complete() or self.raw is None else len(self.raw) / 2 # ASCII hex string
+        return len(self.serialize(True)) / 2 if not self.is_complete() or self.raw is None else len(self.raw) / 2 # ASCII hex string
 
     @classmethod
     def estimated_input_size(self, txin):
         '''Return an estimated of serialized input size in bytes.'''
-        return len(self.serialize_input(txin, -1, -1)) / 2
+        script = self.input_script(txin, True)
+        return len(self.serialize_input(txin, script)) / 2
 
     def signature_count(self):
         r = 0
@@ -723,13 +800,13 @@ class Transaction:
                     txin['pubkeys'][ii] = pubkey
                     self._inputs[i] = txin
                     # add signature
-                    for_sig = Hash(self.tx_for_sig(i).decode('hex'))
+                    pre_hash = Hash(self.serialize_preimage(i).decode('hex'))
                     pkey = regenerate_key(sec)
                     secexp = pkey.secret
-                    private_key = bitcoin.MySigningKey.from_secret_exponent( secexp, curve = SECP256k1 )
+                    private_key = bitcoin.MySigningKey.from_secret_exponent(secexp, curve = SECP256k1)
                     public_key = private_key.get_verifying_key()
-                    sig = private_key.sign_digest_deterministic( for_sig, hashfunc=hashlib.sha256, sigencode = ecdsa.util.sigencode_der )
-                    assert public_key.verify_digest( sig, for_sig, sigdecode = ecdsa.util.sigdecode_der)
+                    sig = private_key.sign_digest_deterministic(pre_hash, hashfunc=hashlib.sha256, sigencode = ecdsa.util.sigencode_der)
+                    assert public_key.verify_digest(sig, pre_hash, sigdecode = ecdsa.util.sigdecode_der)
                     txin['signatures'][ii] = sig.encode('hex')
                     self._inputs[i] = txin
         print_error("is_complete", self.is_complete())

lib/version.py

@@ -3,4 +3,14 @@ PROTOCOL_VERSION = '0.10'   # protocol version requested
 
 # The hash of the mnemonic seed must begin with this
 SEED_PREFIX      = '01'      # Electrum standard wallet
+SEED_PREFIX_SW   = '02'      # Electrum segwit wallet
 SEED_PREFIX_2FA  = '101'     # extended seed for two-factor authentication
+
+
+def seed_prefix(seed_type):
+    if seed_type == 'standard':
+        return SEED_PREFIX
+    elif seed_type == 'segwit':
+        return SEED_PREFIX_SW
+    elif seed_type == '2Fa':
+        return SEED_PREFIX_2FA

lib/wallet.py

@@ -52,6 +52,7 @@ from version import *
 from keystore import load_keystore, Hardware_KeyStore
 from storage import multisig_type
 
+import transaction
 from transaction import Transaction
 from plugins import run_hook
 import bitcoin
@@ -436,7 +437,7 @@ class Abstract_Wallet(PrintError):
         label = ''
         height = conf = timestamp = None
         if tx.is_complete():
-            tx_hash = tx.hash()
+            tx_hash = tx.txid()
             if tx_hash in self.transactions.keys():
                 label = self.get_label(tx_hash)
                 height, conf, timestamp = self.get_tx_height(tx_hash)
@@ -879,7 +880,7 @@ class Abstract_Wallet(PrintError):
             pubkey = public_key_from_private_key(privkey)
             address = address_from_private_key(privkey)
             u = network.synchronous_get(('blockchain.address.listunspent', [address]))
-            pay_script = Transaction.pay_script(TYPE_ADDRESS, address)
+            pay_script = transaction.get_scriptPubKey(address)
             for item in u:
                 if len(inputs) >= imax:
                     break
@@ -1381,45 +1382,9 @@ class Imported_Wallet(Abstract_Wallet):
         txin['x_pubkeys'] = [ xpubkey ]
         txin['pubkeys'] = [ xpubkey ]
         txin['signatures'] = [None]
+        txin['type'] = 'unknown'
 
 
-class P2PKH_Wallet(Abstract_Wallet):
-
-    def pubkeys_to_address(self, pubkey):
-        return public_key_to_bc_address(pubkey.decode('hex'))
-
-    def load_keystore(self):
-        self.keystore = load_keystore(self.storage, 'keystore')
-
-    def get_pubkey(self, c, i):
-        pubkey_list = self.change_pubkeys if c else self.receiving_pubkeys
-        return pubkey_list[i]
-
-    def get_public_keys(self, address):
-        return [self.get_public_key(address)]
-
-    def add_input_sig_info(self, txin, address):
-        if not self.keystore.can_import():
-            txin['derivation'] = derivation = self.get_address_index(address)
-            x_pubkey = self.keystore.get_xpubkey(*derivation)
-            pubkey = self.get_pubkey(*derivation)
-        else:
-            pubkey = self.get_public_key(address)
-            assert pubkey is not None
-            x_pubkey = pubkey
-        txin['x_pubkeys'] = [x_pubkey]
-        txin['pubkeys'] = [pubkey]
-        txin['signatures'] = [None]
-        txin['redeemPubkey'] = pubkey
-        txin['num_sig'] = 1
-
-    def sign_message(self, address, message, password):
-        index = self.get_address_index(address)
-        return self.keystore.sign_message(index, message, password)
-
-    def decrypt_message(self, pubkey, message, password):
-        index = self.get_pubkey_index(pubkey)
-        return self.keystore.decrypt_message(index, message, password)
 
 
 class Deterministic_Wallet(Abstract_Wallet):
@@ -1545,8 +1510,53 @@ class Deterministic_Wallet(Abstract_Wallet):
 
 
 
-class Standard_Wallet(Deterministic_Wallet, P2PKH_Wallet):
-    wallet_type = 'standard'
+class Simple_Wallet(Abstract_Wallet):
+
+    """ Wallet with a single pubkey per address """
+
+    def load_keystore(self):
+        self.keystore = load_keystore(self.storage, 'keystore')
+
+    def get_pubkey(self, c, i):
+        pubkey_list = self.change_pubkeys if c else self.receiving_pubkeys
+        return pubkey_list[i]
+
+    def get_public_keys(self, address):
+        return [self.get_public_key(address)]
+
+    def add_input_sig_info(self, txin, address):
+        if not self.keystore.can_import():
+            txin['derivation'] = derivation = self.get_address_index(address)
+            x_pubkey = self.keystore.get_xpubkey(*derivation)
+            pubkey = self.get_pubkey(*derivation)
+        else:
+            pubkey = self.get_public_key(address)
+            assert pubkey is not None
+            x_pubkey = pubkey
+        txin['x_pubkeys'] = [x_pubkey]
+        txin['pubkeys'] = [pubkey]
+        txin['signatures'] = [None]
+
+        addrtype, hash160 = bc_address_to_hash_160(address)
+        if addrtype == bitcoin.ADDRTYPE_P2SH:
+            txin['redeemScript'] = self.pubkeys_to_redeem_script(pubkey)
+            txin['type'] = 'p2wpkh-p2sh'
+        else:
+            txin['redeemPubkey'] = pubkey
+            txin['type'] = 'p2pkh'
+
+        txin['num_sig'] = 1
+
+    def sign_message(self, address, message, password):
+        index = self.get_address_index(address)
+        return self.keystore.sign_message(index, message, password)
+
+    def decrypt_message(self, pubkey, message, password):
+        index = self.get_pubkey_index(pubkey)
+        return self.keystore.decrypt_message(index, message, password)
+
+
+class Simple_Deterministic_Wallet(Deterministic_Wallet, Simple_Wallet):
 
     def __init__(self, storage):
         Deterministic_Wallet.__init__(self, storage)
@@ -1607,7 +1617,35 @@ class Standard_Wallet(Deterministic_Wallet, P2PKH_Wallet):
         return addr
 
 
-class Multisig_Wallet(Deterministic_Wallet):
+class P2SH:
+
+    def pubkeys_to_redeem_script(self, pubkeys):
+        raise NotImplementedError()
+
+    def pubkeys_to_address(self, pubkeys):
+        redeem_script = self.pubkeys_to_redeem_script(pubkeys)
+        return bitcoin.hash160_to_p2sh(hash_160(redeem_script.decode('hex')))
+
+
+class P2PKH:
+
+    def pubkeys_to_address(self, pubkey):
+        return bitcoin.public_key_to_p2pkh(pubkey.decode('hex'))
+
+
+class Standard_Wallet(Simple_Deterministic_Wallet, P2PKH):
+    wallet_type = 'standard'
+
+
+class Segwit_Wallet(Simple_Deterministic_Wallet, P2SH):
+    wallet_type = 'segwit'
+
+    def pubkeys_to_redeem_script(self, pubkey):
+        return transaction.segwit_script(pubkey)
+
+
+
+class Multisig_Wallet(Deterministic_Wallet, P2SH):
     # generic m of n
     gap_limit = 20
 
@@ -1622,12 +1660,10 @@ class Multisig_Wallet(Deterministic_Wallet):
 
     def redeem_script(self, c, i):
         pubkeys = self.get_pubkeys(c, i)
-        return Transaction.multisig_script(sorted(pubkeys), self.m)
+        return transaction.multisig_script(sorted(pubkeys), self.m)
 
-    def pubkeys_to_address(self, pubkeys):
-        redeem_script = Transaction.multisig_script(sorted(pubkeys), self.m)
-        address = hash_160_to_bc_address(hash_160(redeem_script.decode('hex')), bitcoin.ADDRTYPE_P2SH)
-        return address
+    def pubkeys_to_redeem_script(self, pubkeys):
+        return transaction.multisig_script(sorted(pubkeys), self.m)
 
     def new_pubkeys(self, c, i):
         return [k.derive_pubkey(c, i) for k in self.get_keystores()]
@@ -1683,6 +1719,7 @@ class Multisig_Wallet(Deterministic_Wallet):
         x_pubkeys = [k.get_xpubkey(*derivation) for k in self.get_keystores()]
         # sort pubkeys and x_pubkeys, using the order of pubkeys
         pubkeys, x_pubkeys = zip(*sorted(zip(pubkeys, x_pubkeys)))
+        txin['type'] = 'p2sh'
         txin['pubkeys'] = list(pubkeys)
         txin['x_pubkeys'] = list(x_pubkeys)
         txin['signatures'] = [None] * len(pubkeys)
@@ -1699,7 +1736,8 @@ wallet_constructors = {
     'standard': Standard_Wallet,
     'old': Standard_Wallet,
     'xpub': Standard_Wallet,
-    'imported': Imported_Wallet
+    'imported': Imported_Wallet,
+    'segwit': Segwit_Wallet
 }
 
 def register_constructor(wallet_type, constructor):