Replace makeInt with make_int

2020-10-31 22:08:30 +02:00 · 2020-10-31 22:08:30 +02:00 · 5d84d54e6f
commit 5d84d54e6f
parent 4636d31ea9
33 changed files with 6838 additions and 29 deletions
--- a/basicswap/basicswap.py
+++ b/basicswap/basicswap.py
@ -19,6 +19,11 @@ import secrets
 from sqlalchemy.orm import sessionmaker, scoped_session
 from enum import IntEnum, auto

+from .interface_part import PARTInterface
+from .interface_btc import BTCInterface
+from .interface_ltc import LTCInterface
+from .interface_xmr import XMRInterface
+
 from . import __version__
 from .util import (
    COIN,
@ -31,7 +36,7 @@ from .util import (
    decodeWif,
    toWIF,
    getKeyID,
-    makeInt,
+    make_int,
 )
 from .chainparams import (
    chainparams,
@ -417,6 +422,27 @@ class BasicSwap(BaseApp):
            'chain_lookups': chain_client_settings.get('chain_lookups', 'local'),
        }

+        if self.coin_clients[coin]['connection_type'] == 'rpc':
+            if coin == Coins.XMR:
+                self.coin_clients[coin]['walletrpcport'] = chain_client_settings.get('walletrpcport', chainparams[coin][self.chain]['walletrpcport'])
+                if 'walletrpcpassword' in chain_client_settings:
+                    self.coin_clients[coin]['walletrpcauth'] = chain_client_settings['walletrpcuser'] + ':' + chain_client_settings['walletrpcpassword']
+                else:
+                    raise ValueError('Missing XMR wallet rpc credentials.')
+            self.coin_clients[coin]['interface'] = self.createInterface(coin)
+
+    def createInterface(self, coin):
+        if coin == Coins.PART:
+            return PARTInterface(self.coin_clients[coin])
+        elif coin == Coins.BTC:
+            return BTCInterface(self.coin_clients[coin])
+        elif coin == Coins.LTC:
+            return LTCInterface(self.coin_clients[coin])
+        elif coin == Coins.XMR:
+            return XMRInterface(self.coin_clients[coin])
+        else:
+            raise ValueError('Unknown coin type')
+
    def setCoinRunParams(self, coin):
        cc = self.coin_clients[coin]
        if cc['connection_type'] == 'rpc' and cc['rpcauth'] is None:
@ -1699,7 +1725,7 @@ class BasicSwap(BaseApp):
                continue
            # Verify amount
            if assert_amount:
-                assert(makeInt(o['amount']) == int(assert_amount)), 'Incorrect output amount in txn {}: {} != {}.'.format(assert_txid, makeInt(o['amount']), int(assert_amount))
+                assert(make_int(o['amount']) == int(assert_amount)), 'Incorrect output amount in txn {}: {} != {}.'.format(assert_txid, make_int(o['amount']), int(assert_amount))

            if not sum_output:
                if o['height'] > 0:
@ -1711,7 +1737,7 @@ class BasicSwap(BaseApp):
                    'index': o['vout'],
                    'height': o['height'],
                    'n_conf': n_conf,
-                    'value': makeInt(o['amount']),
+                    'value': make_int(o['amount']),
                }
            else:
                sum_unspent += o['amount'] * COIN
@ -1744,7 +1770,7 @@ class BasicSwap(BaseApp):
                    # Verify amount
                    vout = getVoutByAddress(initiate_txn, p2sh)

-                    out_value = makeInt(initiate_txn['vout'][vout]['value'])
+                    out_value = make_int(initiate_txn['vout'][vout]['value'])
                    assert(out_value == int(bid.amount)), 'Incorrect output amount in initiate txn {}: {} != {}.'.format(initiate_txnid_hex, out_value, int(bid.amount))

                    bid.initiate_tx.conf = initiate_txn['confirmations']
@ -2442,8 +2468,8 @@ class BasicSwap(BaseApp):
            'deposit_address': self.getCachedAddressForCoin(coin),
            'name': chainparams[coin]['name'].capitalize(),
            'blocks': blockchaininfo['blocks'],
-            'balance': format8(makeInt(walletinfo['balance'])),
-            'unconfirmed': format8(makeInt(walletinfo.get('unconfirmed_balance'))),
+            'balance': format8(make_int(walletinfo['balance'])),
+            'unconfirmed': format8(make_int(walletinfo.get('unconfirmed_balance'))),
            'synced': '{0:.2f}'.format(round(blockchaininfo['verificationprogress'], 2)),
        }
        return rv
--- a/basicswap/chainparams.py
+++ b/basicswap/chainparams.py
@ -14,8 +14,9 @@ class Coins(IntEnum):
    PART = 1
    BTC = 2
    LTC = 3
-    # DCR = 4
+    #DCR = 4
    NMC = 5
+    XMR = 6


 chainparams = {
@ -156,5 +157,26 @@ chainparams = {
            'min_amount': 1000,
            'max_amount': 100000 * COIN,
        }
+    },
+    Coins.XMR: {
+        'name': 'monero',
+        'ticker': 'XMR',
+        'client': 'xmr',
+        'mainnet': {
+            'rpcport': 18081,
+            'walletrpcport': 18082,
+        },
+        'testnet': {
+            'rpcport': 28081,
+            'walletrpcport': 28082,
+        },
+        'regtest': {
+            'rpcport': 18081,
+            'walletrpcport': 18082,
+        }
    }
 }
+
+class CoinInterface:
+    pass
+
--- a/basicswap/contrib/MoneroPy/init.py
+++ b/basicswap/contrib/MoneroPy/init.py
--- a/basicswap/contrib/MoneroPy/base58.py
+++ b/basicswap/contrib/MoneroPy/base58.py
@ -0,0 +1,168 @@
+# MoneroPy - A python toolbox for Monero
+# Copyright (C) 2016 The MoneroPy Developers.
+#
+# MoneroPy is released under the BSD 3-Clause license. Use and redistribution of
+# this software is subject to the license terms in the LICENSE file found in the
+# top-level directory of this distribution.
+
+__alphabet = [ord(s) for s in '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz']
+__b58base = 58
+__UINT64MAX = 2**64
+__encodedBlockSizes = [0, 2, 3, 5, 6, 7, 9, 10, 11]
+__fullBlockSize = 8
+__fullEncodedBlockSize = 11
+
+def _hexToBin(hex):
+    if len(hex) % 2 != 0:
+        return "Hex string has invalid length!"
+    return [int(hex[i*2:i*2+2], 16) for i in range(len(hex)//2)]
+
+def _binToHex(bin):
+    return "".join([("0" + hex(int(bin[i])).split('x')[1])[-2:] for i in range(len(bin))])
+
+def _strToBin(a):
+    return [ord(s) for s in a]
+
+def _binToStr(bin):
+    return ''.join([chr(bin[i]) for i in range(len(bin))])
+
+def _uint8be_to_64(data):
+    l_data = len(data)
+
+    if l_data < 1 or l_data > 8:
+        return "Invalid input length"
+
+    res = 0
+    switch = 9 - l_data
+    for i in range(l_data):
+        if switch == 1:
+            res = res << 8 | data[i]
+        elif switch == 2:
+            res = res << 8 | data[i]
+        elif switch == 3:
+            res = res << 8 | data[i]
+        elif switch == 4:
+            res = res << 8 | data[i]
+        elif switch == 5:
+            res = res << 8 | data[i]
+        elif switch == 6:
+            res = res << 8 | data[i]
+        elif switch == 7:
+            res = res << 8 | data[i]
+        elif switch == 8:
+            res = res << 8 | data[i]
+        else:
+            return "Impossible condition"
+    return res
+
+def _uint64_to_8be(num, size):
+    res = [0] * size;
+    if size < 1 or size > 8:
+        return "Invalid input length"
+
+    twopow8 = 2**8
+    for i in range(size-1,-1,-1):
+        res[i] = num % twopow8
+        num = num // twopow8
+
+    return res
+
+def encode_block(data, buf, index):
+    l_data = len(data)
+
+    if l_data < 1 or l_data > __fullEncodedBlockSize:
+        return "Invalid block length: " + str(l_data)
+
+    num = _uint8be_to_64(data)
+    i = __encodedBlockSizes[l_data] - 1
+
+    while num > 0:
+        remainder = num % __b58base
+        num = num // __b58base
+        buf[index+i] = __alphabet[remainder];
+        i -= 1
+
+    return buf
+
+def encode(hex):
+    '''Encode hexadecimal string as base58 (ex: encoding a Monero address).'''
+    data = _hexToBin(hex)
+    l_data = len(data)
+
+    if l_data == 0:
+        return ""
+
+    full_block_count = l_data // __fullBlockSize
+    last_block_size = l_data % __fullBlockSize
+    res_size = full_block_count * __fullEncodedBlockSize + __encodedBlockSizes[last_block_size]
+
+    res = [0] * res_size
+    for i in range(res_size):
+        res[i] = __alphabet[0]
+
+    for i in range(full_block_count):
+        res = encode_block(data[(i*__fullBlockSize):(i*__fullBlockSize+__fullBlockSize)], res, i * __fullEncodedBlockSize)
+
+    if last_block_size > 0:
+        res = encode_block(data[(full_block_count*__fullBlockSize):(full_block_count*__fullBlockSize+last_block_size)], res, full_block_count * __fullEncodedBlockSize)
+
+    return _binToStr(res)
+
+def decode_block(data, buf, index):
+    l_data = len(data)
+
+    if l_data < 1 or l_data > __fullEncodedBlockSize:
+        return "Invalid block length: " + l_data
+
+    res_size = __encodedBlockSizes.index(l_data)
+    if res_size <= 0:
+        return "Invalid block size"
+
+    res_num = 0
+    order = 1
+    for i in range(l_data-1, -1, -1):
+        digit = __alphabet.index(data[i])
+        if digit < 0:
+            return "Invalid symbol"
+
+        product = order * digit + res_num
+        if product > __UINT64MAX:
+            return "Overflow"
+
+        res_num = product
+        order = order * __b58base
+
+    if res_size < __fullBlockSize and 2**(8 * res_size) <= res_num:
+        return "Overflow 2"
+
+    tmp_buf = _uint64_to_8be(res_num, res_size)
+    for i in range(len(tmp_buf)):
+        buf[i+index] = tmp_buf[i]
+
+    return buf
+
+def decode(enc):
+    '''Decode a base58 string (ex: a Monero address) into hexidecimal form.'''
+    enc = _strToBin(enc)
+    l_enc = len(enc)
+
+    if l_enc == 0:
+        return ""
+
+    full_block_count = l_enc // __fullEncodedBlockSize
+    last_block_size = l_enc % __fullEncodedBlockSize
+    last_block_decoded_size = __encodedBlockSizes.index(last_block_size)
+
+    if last_block_decoded_size < 0:
+        return "Invalid encoded length"
+
+    data_size = full_block_count * __fullBlockSize + last_block_decoded_size
+
+    data = [0] * data_size
+    for i in range(full_block_count):
+        data = decode_block(enc[(i*__fullEncodedBlockSize):(i*__fullEncodedBlockSize+__fullEncodedBlockSize)], data, i * __fullBlockSize)
+
+    if last_block_size > 0:
+        data = decode_block(enc[(full_block_count*__fullEncodedBlockSize):(full_block_count*__fullEncodedBlockSize+last_block_size)], data, full_block_count * __fullBlockSize)
+
+    return _binToHex(data)
--- a/basicswap/contrib/ellipticcurve.py
+++ b/basicswap/contrib/ellipticcurve.py
@ -0,0 +1,486 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+#
+# Implementation of elliptic curves, for cryptographic applications.
+#
+# This module doesn't provide any way to choose a random elliptic
+# curve, nor to verify that an elliptic curve was chosen randomly,
+# because one can simply use NIST's standard curves.
+#
+# Notes from X9.62-1998 (draft):
+#   Nomenclature:
+#     - Q is a public key.
+#     The "Elliptic Curve Domain Parameters" include:
+#     - q is the "field size", which in our case equals p.
+#     - p is a big prime.
+#     - G is a point of prime order (5.1.1.1).
+#     - n is the order of G (5.1.1.1).
+#   Public-key validation (5.2.2):
+#     - Verify that Q is not the point at infinity.
+#     - Verify that X_Q and Y_Q are in [0,p-1].
+#     - Verify that Q is on the curve.
+#     - Verify that nQ is the point at infinity.
+#   Signature generation (5.3):
+#     - Pick random k from [1,n-1].
+#   Signature checking (5.4.2):
+#     - Verify that r and s are in [1,n-1].
+#
+# Version of 2008.11.25.
+#
+# Revision history:
+#    2005.12.31 - Initial version.
+#    2008.11.25 - Change CurveFp.is_on to contains_point.
+#
+# Written in 2005 by Peter Pearson and placed in the public domain.
+
+def inverse_mod(a, m):
+    """Inverse of a mod m."""
+
+    if a < 0 or m <= a:
+        a = a % m
+
+    # From Ferguson and Schneier, roughly:
+
+    c, d = a, m
+    uc, vc, ud, vd = 1, 0, 0, 1
+    while c != 0:
+        q, c, d = divmod(d, c) + (c,)
+        uc, vc, ud, vd = ud - q * uc, vd - q * vc, uc, vc
+
+    # At this point, d is the GCD, and ud*a+vd*m = d.
+    # If d == 1, this means that ud is a inverse.
+
+    assert d == 1
+    if ud > 0:
+        return ud
+    else:
+        return ud + m
+
+
+def modular_sqrt(a, p):
+    # from http://eli.thegreenplace.net/2009/03/07/computing-modular-square-roots-in-python/
+    """ Find a quadratic residue (mod p) of 'a'. p
+    must be an odd prime.
+
+    Solve the congruence of the form:
+    x^2 = a (mod p)
+    And returns x. Note that p - x is also a root.
+
+    0 is returned is no square root exists for
+    these a and p.
+
+    The Tonelli-Shanks algorithm is used (except
+    for some simple cases in which the solution
+    is known from an identity). This algorithm
+    runs in polynomial time (unless the
+    generalized Riemann hypothesis is false).
+    """
+    # Simple cases
+    #
+    if legendre_symbol(a, p) != 1:
+        return 0
+    elif a == 0:
+        return 0
+    elif p == 2:
+        return p
+    elif p % 4 == 3:
+        return pow(a, (p + 1) // 4, p)
+
+    # Partition p-1 to s * 2^e for an odd s (i.e.
+    # reduce all the powers of 2 from p-1)
+    #
+    s = p - 1
+    e = 0
+    while s % 2 == 0:
+        s /= 2
+        e += 1
+
+    # Find some 'n' with a legendre symbol n|p = -1.
+    # Shouldn't take long.
+    #
+    n = 2
+    while legendre_symbol(n, p) != -1:
+        n += 1
+
+    # Here be dragons!
+    # Read the paper "Square roots from 1; 24, 51,
+    # 10 to Dan Shanks" by Ezra Brown for more
+    # information
+    #
+
+    # x is a guess of the square root that gets better
+    # with each iteration.
+    # b is the "fudge factor" - by how much we're off
+    # with the guess. The invariant x^2 = ab (mod p)
+    # is maintained throughout the loop.
+    # g is used for successive powers of n to update
+    # both a and b
+    # r is the exponent - decreases with each update
+    #
+    x = pow(a, (s + 1) // 2, p)
+    b = pow(a, s, p)
+    g = pow(n, s, p)
+    r = e
+
+    while True:
+        t = b
+        m = 0
+        for m in range(r):
+            if t == 1:
+                break
+            t = pow(t, 2, p)
+
+        if m == 0:
+            return x
+
+        gs = pow(g, 2 ** (r - m - 1), p)
+        g = (gs * gs) % p
+        x = (x * gs) % p
+        b = (b * g) % p
+        r = m
+
+
+def legendre_symbol(a, p):
+    """ Compute the Legendre symbol a|p using
+    Euler's criterion. p is a prime, a is
+    relatively prime to p (if p divides
+    a, then a|p = 0)
+
+    Returns 1 if a has a square root modulo
+    p, -1 otherwise.
+    """
+    ls = pow(a, (p - 1) // 2, p)
+    return -1 if ls == p - 1 else ls
+
+
+def jacobi_symbol(n, k):
+    """Compute the Jacobi symbol of n modulo k
+
+    See http://en.wikipedia.org/wiki/Jacobi_symbol
+
+    For our application k is always prime, so this is the same as the Legendre symbol."""
+    assert k > 0 and k & 1, "jacobi symbol is only defined for positive odd k"
+    n %= k
+    t = 0
+    while n != 0:
+        while n & 1 == 0:
+            n >>= 1
+            r = k & 7
+            t ^= (r == 3 or r == 5)
+        n, k = k, n
+        t ^= (n & k & 3 == 3)
+        n = n % k
+    if k == 1:
+        return -1 if t else 1
+    return 0
+
+
+class CurveFp(object):
+    """Elliptic Curve over the field of integers modulo a prime."""
+    def __init__(self, p, a, b):
+        """The curve of points satisfying y^2 = x^3 + a*x + b (mod p)."""
+        self.__p = p
+        self.__a = a
+        self.__b = b
+
+    def p(self):
+        return self.__p
+
+    def a(self):
+        return self.__a
+
+    def b(self):
+        return self.__b
+
+    def contains_point(self, x, y):
+        """Is the point (x,y) on this curve?"""
+        return (y * y - (x * x * x + self.__a * x + self.__b)) % self.__p == 0
+
+
+class Point(object):
+    """ A point on an elliptic curve. Altering x and y is forbidding,
+        but they can be read by the x() and y() methods."""
+    def __init__(self, curve, x, y, order=None):
+        """curve, x, y, order; order (optional) is the order of this point."""
+        self.__curve = curve
+        self.__x = x
+        self.__y = y
+        self.__order = order
+        # self.curve is allowed to be None only for INFINITY:
+        if self.__curve:
+            assert self.__curve.contains_point(x, y)
+        if order:
+            assert self * order == INFINITY
+
+    def __eq__(self, other):
+        """Return 1 if the points are identical, 0 otherwise."""
+        if self.__curve == other.__curve \
+           and self.__x == other.__x \
+           and self.__y == other.__y:
+            return 1
+        else:
+            return 0
+
+    def __add__(self, other):
+        """Add one point to another point."""
+
+        # X9.62 B.3:
+        if other == INFINITY:
+            return self
+        if self == INFINITY:
+            return other
+        assert self.__curve == other.__curve
+        if self.__x == other.__x:
+            if (self.__y + other.__y) % self.__curve.p() == 0:
+                return INFINITY
+            else:
+                return self.double()
+
+        p = self.__curve.p()
+
+        l = ((other.__y - self.__y) * inverse_mod(other.__x - self.__x, p)) % p
+
+        x3 = (l * l - self.__x - other.__x) % p
+        y3 = (l * (self.__x - x3) - self.__y) % p
+
+        return Point(self.__curve, x3, y3)
+
+    def __sub__(self, other):
+        #The inverse of a point P=(xP,yP) is its reflexion across the x-axis : P′=(xP,−yP).
+        #If you want to compute Q−P, just replace yP by −yP in the usual formula for point addition.
+
+        # X9.62 B.3:
+        if other == INFINITY:
+            return self
+        if self == INFINITY:
+            return other
+        assert self.__curve == other.__curve
+
+        p = self.__curve.p()
+        #opi = inverse_mod(other.__y, p)
+        opi = -other.__y % p
+        #print(opi)
+        #print(-other.__y % p)
+
+        if self.__x == other.__x:
+            if (self.__y + opi) % self.__curve.p() == 0:
+                return INFINITY
+            else:
+                return self.double
+
+        l = ((opi - self.__y) * inverse_mod(other.__x - self.__x, p)) % p
+
+        x3 = (l * l - self.__x - other.__x) % p
+        y3 = (l * (self.__x - x3) - self.__y) % p
+
+        return Point(self.__curve, x3, y3)
+
+    def __mul__(self, e):
+        if self.__order:
+            e %= self.__order
+        if e == 0 or self == INFINITY:
+            return INFINITY
+        result, q = INFINITY, self
+        while e:
+            if e & 1:
+                result += q
+            e, q = e >> 1, q.double()
+        return result
+
+    """
+    def __mul__(self, other):
+        #Multiply a point by an integer.
+
+        def leftmost_bit( x ):
+            assert x > 0
+            result = 1
+            while result <= x: result = 2 * result
+            return result // 2
+
+        e = other
+        if self.__order: e = e % self.__order
+        if e == 0: return INFINITY
+        if self == INFINITY: return INFINITY
+        assert e > 0
+
+        # From X9.62 D.3.2:
+
+        e3 = 3 * e
+        negative_self = Point( self.__curve, self.__x, -self.__y, self.__order )
+        i = leftmost_bit( e3 ) // 2
+        result = self
+        # print "Multiplying %s by %d (e3 = %d):" % ( self, other, e3 )
+        while i > 1:
+            result = result.double()
+            if ( e3 & i ) != 0 and ( e & i ) == 0: result = result + self
+            if ( e3 & i ) == 0 and ( e & i ) != 0: result = result + negative_self
+            # print ". . . i = %d, result = %s" % ( i, result )
+            i = i // 2
+
+        return result
+    """
+
+    def __rmul__(self, other):
+        """Multiply a point by an integer."""
+
+        return self * other
+
+    def __str__(self):
+        if self == INFINITY:
+            return "infinity"
+        return "(%d, %d)" % (self.__x, self.__y)
+
+    def inverse(self):
+        return Point(self.__curve, self.__x, -self.__y % self.__curve.p())
+
+    def double(self):
+        """Return a new point that is twice the old."""
+
+        if self == INFINITY:
+            return INFINITY
+
+        # X9.62 B.3:
+
+        p = self.__curve.p()
+        a = self.__curve.a()
+
+        l = ((3 * self.__x * self.__x + a) * inverse_mod(2 * self.__y, p)) % p
+
+        x3 = (l * l - 2 * self.__x) % p
+        y3 = (l * (self.__x - x3) - self.__y) % p
+
+        return Point(self.__curve, x3, y3)
+
+    def x(self):
+        return self.__x
+
+    def y(self):
+        return self.__y
+
+    def pair(self):
+        return (self.__x, self.__y)
+
+    def curve(self):
+        return self.__curve
+
+    def order(self):
+        return self.__order
+
+
+# This one point is the Point At Infinity for all purposes:
+INFINITY = Point(None, None, None)
+
+
+def __main__():
+
+    class FailedTest(Exception):
+        pass
+
+    def test_add(c, x1, y1, x2, y2, x3, y3):
+        """We expect that on curve c, (x1,y1) + (x2, y2 ) = (x3, y3)."""
+        p1 = Point(c, x1, y1)
+        p2 = Point(c, x2, y2)
+        p3 = p1 + p2
+        print("%s + %s = %s" % (p1, p2, p3))
+        if p3.x() != x3 or p3.y() != y3:
+            raise FailedTest("Failure: should give (%d,%d)." % (x3, y3))
+        else:
+            print(" Good.")
+
+    def test_double(c, x1, y1, x3, y3):
+        """We expect that on curve c, 2*(x1,y1) = (x3, y3)."""
+        p1 = Point(c, x1, y1)
+        p3 = p1.double()
+        print("%s doubled = %s" % (p1, p3))
+        if p3.x() != x3 or p3.y() != y3:
+            raise FailedTest("Failure: should give (%d,%d)." % (x3, y3))
+        else:
+            print(" Good.")
+
+    def test_double_infinity(c):
+        """We expect that on curve c, 2*INFINITY = INFINITY."""
+        p1 = INFINITY
+        p3 = p1.double()
+        print("%s doubled = %s" % (p1, p3))
+        if p3.x() != INFINITY.x() or p3.y() != INFINITY.y():
+            raise FailedTest("Failure: should give (%d,%d)." % (INFINITY.x(), INFINITY.y()))
+        else:
+            print(" Good.")
+
+    def test_multiply(c, x1, y1, m, x3, y3):
+        """We expect that on curve c, m*(x1,y1) = (x3,y3)."""
+        p1 = Point(c, x1, y1)
+        p3 = p1 * m
+        print("%s * %d = %s" % (p1, m, p3))
+        if p3.x() != x3 or p3.y() != y3:
+            raise FailedTest("Failure: should give (%d,%d)." % (x3, y3))
+        else:
+            print(" Good.")
+
+    # A few tests from X9.62 B.3:
+
+    c = CurveFp(23, 1, 1)
+    test_add(c, 3, 10, 9, 7, 17, 20)
+    test_double(c, 3, 10, 7, 12)
+    test_add(c, 3, 10, 3, 10, 7, 12)    # (Should just invoke double.)
+    test_multiply(c, 3, 10, 2, 7, 12)
+
+    test_double_infinity(c)
+
+    # From X9.62 I.1 (p. 96):
+
+    g = Point(c, 13, 7, 7)
+
+    check = INFINITY
+    for i in range(7 + 1):
+        p = (i % 7) * g
+        print("%s * %d = %s, expected %s . . ." % (g, i, p, check))
+        if p == check:
+            print(" Good.")
+        else:
+            raise FailedTest("Bad.")
+        check = check + g
+
+    # NIST Curve P-192:
+    p = 6277101735386680763835789423207666416083908700390324961279
+    r = 6277101735386680763835789423176059013767194773182842284081
+    #s = 0x3045ae6fc8422f64ed579528d38120eae12196d5L
+    c = 0x3099d2bbbfcb2538542dcd5fb078b6ef5f3d6fe2c745de65
+    b = 0x64210519e59c80e70fa7e9ab72243049feb8deecc146b9b1
+    Gx = 0x188da80eb03090f67cbf20eb43a18800f4ff0afd82ff1012
+    Gy = 0x07192b95ffc8da78631011ed6b24cdd573f977a11e794811
+
+    c192 = CurveFp(p, -3, b)
+    p192 = Point(c192, Gx, Gy, r)
+
+    # Checking against some sample computations presented
+    # in X9.62:
+
+    d = 651056770906015076056810763456358567190100156695615665659
+    Q = d * p192
+    if Q.x() != 0x62B12D60690CDCF330BABAB6E69763B471F994DD702D16A5:
+        raise FailedTest("p192 * d came out wrong.")
+    else:
+        print("p192 * d came out right.")
+
+    k = 6140507067065001063065065565667405560006161556565665656654
+    R = k * p192
+    if R.x() != 0x885052380FF147B734C330C43D39B2C4A89F29B0F749FEAD \
+       or R.y() != 0x9CF9FA1CBEFEFB917747A3BB29C072B9289C2547884FD835:
+        raise FailedTest("k * p192 came out wrong.")
+    else:
+        print("k * p192 came out right.")
+
+    u1 = 2563697409189434185194736134579731015366492496392189760599
+    u2 = 6266643813348617967186477710235785849136406323338782220568
+    temp = u1 * p192 + u2 * Q
+    if temp.x() != 0x885052380FF147B734C330C43D39B2C4A89F29B0F749FEAD \
+       or temp.y() != 0x9CF9FA1CBEFEFB917747A3BB29C072B9289C2547884FD835:
+        raise FailedTest("u1 * p192 + u2 * Q came out wrong.")
+    else:
+        print("u1 * p192 + u2 * Q came out right.")
+
+
+if __name__ == "__main__":
+    __main__()
--- a/basicswap/contrib/test_framework/init.py
+++ b/basicswap/contrib/test_framework/init.py
--- a/basicswap/contrib/test_framework/address.py
+++ b/basicswap/contrib/test_framework/address.py
@ -0,0 +1,158 @@
+#!/usr/bin/env python3
+# Copyright (c) 2016-2020 The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+"""Encode and decode BASE58, P2PKH and P2SH addresses."""
+
+import enum
+import unittest
+
+from .script import hash256, hash160, sha256, CScript, OP_0
+from .util import hex_str_to_bytes
+
+from . import segwit_addr
+
+from .util import assert_equal
+
+ADDRESS_BCRT1_UNSPENDABLE = 'bcrt1qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq3xueyj'
+ADDRESS_BCRT1_UNSPENDABLE_DESCRIPTOR = 'addr(bcrt1qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq3xueyj)#juyq9d97'
+# Coins sent to this address can be spent with a witness stack of just OP_TRUE
+ADDRESS_BCRT1_P2WSH_OP_TRUE = 'bcrt1qft5p2uhsdcdc3l2ua4ap5qqfg4pjaqlp250x7us7a8qqhrxrxfsqseac85'
+
+
+class AddressType(enum.Enum):
+    bech32 = 'bech32'
+    p2sh_segwit = 'p2sh-segwit'
+    legacy = 'legacy'  # P2PKH
+
+
+chars = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
+
+
+def byte_to_base58(b, version):
+    result = ''
+    str = b.hex()
+    str = chr(version).encode('latin-1').hex() + str
+    checksum = hash256(hex_str_to_bytes(str)).hex()
+    str += checksum[:8]
+    value = int('0x'+str,0)
+    while value > 0:
+        result = chars[value % 58] + result
+        value //= 58
+    while (str[:2] == '00'):
+        result = chars[0] + result
+        str = str[2:]
+    return result
+
+
+def base58_to_byte(s, verify_checksum=True):
+    if not s:
+        return b''
+    n = 0
+    for c in s:
+        n *= 58
+        assert c in chars
+        digit = chars.index(c)
+        n += digit
+    h = '%x' % n
+    if len(h) % 2:
+        h = '0' + h
+    res = n.to_bytes((n.bit_length() + 7) // 8, 'big')
+    pad = 0
+    for c in s:
+        if c == chars[0]:
+            pad += 1
+        else:
+            break
+    res = b'\x00' * pad + res
+    if verify_checksum:
+        assert_equal(hash256(res[:-4])[:4], res[-4:])
+
+    return res[1:-4], int(res[0])
+
+
+def keyhash_to_p2pkh(hash, main = False, btc = True):
+    assert (len(hash) == 20 or len(hash) == 32)
+    if len(hash) == 20:
+        if btc:
+            version = 0 if main else 111
+        else:
+            version = 56 if main else 118
+        return byte_to_base58(hash, version)
+    version = 57 if main else 119
+    return byte_to_base58(hash, version)
+
+def scripthash_to_p2sh(hash, main = False, btc = True):
+    assert (len(hash) == 20)
+    if btc:
+        version = 5 if main else 196
+    else:
+        version = 60 if main else 122
+    return byte_to_base58(hash, version)
+
+def key_to_p2pkh(key, main = False):
+    key = check_key(key)
+    return keyhash_to_p2pkh(hash160(key), main)
+
+def script_to_p2sh(script, main = False, btc = True):
+    script = check_script(script)
+    return scripthash_to_p2sh(hash160(script), main, btc)
+
+def key_to_p2sh_p2wpkh(key, main = False):
+    key = check_key(key)
+    p2shscript = CScript([OP_0, hash160(key)])
+    return script_to_p2sh(p2shscript, main)
+
+def program_to_witness(version, program, main = False):
+    if (type(program) is str):
+        program = hex_str_to_bytes(program)
+    assert 0 <= version <= 16
+    assert 2 <= len(program) <= 40
+    assert version > 0 or len(program) in [20, 32]
+    return segwit_addr.encode("bc" if main else "bcrt", version, program)
+
+def script_to_p2wsh(script, main = False):
+    script = check_script(script)
+    return program_to_witness(0, sha256(script), main)
+
+def key_to_p2wpkh(key, main = False):
+    key = check_key(key)
+    return program_to_witness(0, hash160(key), main)
+
+def script_to_p2sh_p2wsh(script, main = False):
+    script = check_script(script)
+    p2shscript = CScript([OP_0, sha256(script)])
+    return script_to_p2sh(p2shscript, main)
+
+def check_key(key):
+    if (type(key) is str):
+        key = hex_str_to_bytes(key) # Assuming this is hex string
+    if (type(key) is bytes and (len(key) == 33 or len(key) == 65)):
+        return key
+    assert False
+
+def check_script(script):
+    if (type(script) is str):
+        script = hex_str_to_bytes(script) # Assuming this is hex string
+    if (type(script) is bytes or type(script) is CScript):
+        return script
+    assert False
+
+
+class TestFrameworkScript(unittest.TestCase):
+    def test_base58encodedecode(self):
+        def check_base58(data, version):
+            self.assertEqual(base58_to_byte(byte_to_base58(data, version)), (data, version))
+
+        check_base58(b'\x1f\x8e\xa1p*{\xd4\x94\x1b\xca\tA\xb8R\xc4\xbb\xfe\xdb.\x05', 111)
+        check_base58(b':\x0b\x05\xf4\xd7\xf6l;\xa7\x00\x9fE50)l\x84\\\xc9\xcf', 111)
+        check_base58(b'A\xc1\xea\xf1\x11\x80%Y\xba\xd6\x1b`\xd6+\x1f\x89|c\x92\x8a', 111)
+        check_base58(b'\0A\xc1\xea\xf1\x11\x80%Y\xba\xd6\x1b`\xd6+\x1f\x89|c\x92\x8a', 111)
+        check_base58(b'\0\0A\xc1\xea\xf1\x11\x80%Y\xba\xd6\x1b`\xd6+\x1f\x89|c\x92\x8a', 111)
+        check_base58(b'\0\0\0A\xc1\xea\xf1\x11\x80%Y\xba\xd6\x1b`\xd6+\x1f\x89|c\x92\x8a', 111)
+        check_base58(b'\x1f\x8e\xa1p*{\xd4\x94\x1b\xca\tA\xb8R\xc4\xbb\xfe\xdb.\x05', 0)
+        check_base58(b':\x0b\x05\xf4\xd7\xf6l;\xa7\x00\x9fE50)l\x84\\\xc9\xcf', 0)
+        check_base58(b'A\xc1\xea\xf1\x11\x80%Y\xba\xd6\x1b`\xd6+\x1f\x89|c\x92\x8a', 0)
+        check_base58(b'\0A\xc1\xea\xf1\x11\x80%Y\xba\xd6\x1b`\xd6+\x1f\x89|c\x92\x8a', 0)
+        check_base58(b'\0\0A\xc1\xea\xf1\x11\x80%Y\xba\xd6\x1b`\xd6+\x1f\x89|c\x92\x8a', 0)
+        check_base58(b'\0\0\0A\xc1\xea\xf1\x11\x80%Y\xba\xd6\x1b`\xd6+\x1f\x89|c\x92\x8a', 0)
--- a/basicswap/contrib/test_framework/authproxy.py
+++ b/basicswap/contrib/test_framework/authproxy.py
@ -0,0 +1,204 @@
+# Copyright (c) 2011 Jeff Garzik
+#
+# Previous copyright, from python-jsonrpc/jsonrpc/proxy.py:
+#
+# Copyright (c) 2007 Jan-Klaas Kollhof
+#
+# This file is part of jsonrpc.
+#
+# jsonrpc is free software; you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation; either version 2.1 of the License, or
+# (at your option) any later version.
+#
+# This software is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this software; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+"""HTTP proxy for opening RPC connection to bitcoind.
+
+AuthServiceProxy has the following improvements over python-jsonrpc's
+ServiceProxy class:
+
+- HTTP connections persist for the life of the AuthServiceProxy object
+  (if server supports HTTP/1.1)
+- sends protocol 'version', per JSON-RPC 1.1
+- sends proper, incrementing 'id'
+- sends Basic HTTP authentication headers
+- parses all JSON numbers that look like floats as Decimal
+- uses standard Python json lib
+"""
+
+import base64
+import decimal
+from http import HTTPStatus
+import http.client
+import json
+import logging
+import os
+import socket
+import time
+import urllib.parse
+
+HTTP_TIMEOUT = 30
+USER_AGENT = "AuthServiceProxy/0.1"
+
+log = logging.getLogger("BitcoinRPC")
+
+class JSONRPCException(Exception):
+    def __init__(self, rpc_error, http_status=None):
+        try:
+            errmsg = '%(message)s (%(code)i)' % rpc_error
+        except (KeyError, TypeError):
+            errmsg = ''
+        super().__init__(errmsg)
+        self.error = rpc_error
+        self.http_status = http_status
+
+
+def EncodeDecimal(o):
+    if isinstance(o, decimal.Decimal):
+        return str(o)
+    raise TypeError(repr(o) + " is not JSON serializable")
+
+class AuthServiceProxy():
+    __id_count = 0
+
+    # ensure_ascii: escape unicode as \uXXXX, passed to json.dumps
+    def __init__(self, service_url, service_name=None, timeout=HTTP_TIMEOUT, connection=None, ensure_ascii=True):
+        self.__service_url = service_url
+        self._service_name = service_name
+        self.ensure_ascii = ensure_ascii  # can be toggled on the fly by tests
+        self.__url = urllib.parse.urlparse(service_url)
+        user = None if self.__url.username is None else self.__url.username.encode('utf8')
+        passwd = None if self.__url.password is None else self.__url.password.encode('utf8')
+        authpair = user + b':' + passwd
+        self.__auth_header = b'Basic ' + base64.b64encode(authpair)
+        self.timeout = timeout
+        self._set_conn(connection)
+
+    def __getattr__(self, name):
+        if name.startswith('__') and name.endswith('__'):
+            # Python internal stuff
+            raise AttributeError
+        if self._service_name is not None:
+            name = "%s.%s" % (self._service_name, name)
+        return AuthServiceProxy(self.__service_url, name, connection=self.__conn)
+
+    def _request(self, method, path, postdata):
+        '''
+        Do a HTTP request, with retry if we get disconnected (e.g. due to a timeout).
+        This is a workaround for https://bugs.python.org/issue3566 which is fixed in Python 3.5.
+        '''
+        headers = {'Host': self.__url.hostname,
+                   'User-Agent': USER_AGENT,
+                   'Authorization': self.__auth_header,
+                   'Content-type': 'application/json'}
+        if os.name == 'nt':
+            # Windows somehow does not like to re-use connections
+            # TODO: Find out why the connection would disconnect occasionally and make it reusable on Windows
+            # Avoid "ConnectionAbortedError: [WinError 10053] An established connection was aborted by the software in your host machine"
+            self._set_conn()
+        try:
+            self.__conn.request(method, path, postdata, headers)
+            return self._get_response()
+        except (BrokenPipeError, ConnectionResetError):
+            # Python 3.5+ raises BrokenPipeError when the connection was reset
+            # ConnectionResetError happens on FreeBSD
+            self.__conn.close()
+            self.__conn.request(method, path, postdata, headers)
+            return self._get_response()
+        except OSError as e:
+            retry = (
+                '[WinError 10053] An established connection was aborted by the software in your host machine' in str(e))
+            if retry:
+                self.__conn.close()
+                self.__conn.request(method, path, postdata, headers)
+                return self._get_response()
+            else:
+                raise
+
+    def get_request(self, *args, **argsn):
+        AuthServiceProxy.__id_count += 1
+
+        log.debug("-{}-> {} {}".format(
+            AuthServiceProxy.__id_count,
+            self._service_name,
+            json.dumps(args or argsn, default=EncodeDecimal, ensure_ascii=self.ensure_ascii),
+        ))
+        if args and argsn:
+            raise ValueError('Cannot handle both named and positional arguments')
+        return {'version': '1.1',
+                'method': self._service_name,
+                'params': args or argsn,
+                'id': AuthServiceProxy.__id_count}
+
+    def __call__(self, *args, **argsn):
+        postdata = json.dumps(self.get_request(*args, **argsn), default=EncodeDecimal, ensure_ascii=self.ensure_ascii)
+        response, status = self._request('POST', self.__url.path, postdata.encode('utf-8'))
+        if response['error'] is not None:
+            raise JSONRPCException(response['error'], status)
+        elif 'result' not in response:
+            raise JSONRPCException({
+                'code': -343, 'message': 'missing JSON-RPC result'}, status)
+        elif status != HTTPStatus.OK:
+            raise JSONRPCException({
+                'code': -342, 'message': 'non-200 HTTP status code but no JSON-RPC error'}, status)
+        else:
+            return response['result']
+
+    def batch(self, rpc_call_list):
+        postdata = json.dumps(list(rpc_call_list), default=EncodeDecimal, ensure_ascii=self.ensure_ascii)
+        log.debug("--> " + postdata)
+        response, status = self._request('POST', self.__url.path, postdata.encode('utf-8'))
+        if status != HTTPStatus.OK:
+            raise JSONRPCException({
+                'code': -342, 'message': 'non-200 HTTP status code but no JSON-RPC error'}, status)
+        return response
+
+    def _get_response(self):
+        req_start_time = time.time()
+        try:
+            http_response = self.__conn.getresponse()
+        except socket.timeout:
+            raise JSONRPCException({
+                'code': -344,
+                'message': '%r RPC took longer than %f seconds. Consider '
+                           'using larger timeout for calls that take '
+                           'longer to return.' % (self._service_name,
+                                                  self.__conn.timeout)})
+        if http_response is None:
+            raise JSONRPCException({
+                'code': -342, 'message': 'missing HTTP response from server'})
+
+        content_type = http_response.getheader('Content-Type')
+        if content_type != 'application/json':
+            raise JSONRPCException(
+                {'code': -342, 'message': 'non-JSON HTTP response with \'%i %s\' from server' % (http_response.status, http_response.reason)},
+                http_response.status)
+
+        responsedata = http_response.read().decode('utf8')
+        response = json.loads(responsedata, parse_float=decimal.Decimal)
+        elapsed = time.time() - req_start_time
+        if "error" in response and response["error"] is None:
+            log.debug("<-%s- [%.6f] %s" % (response["id"], elapsed, json.dumps(response["result"], default=EncodeDecimal, ensure_ascii=self.ensure_ascii)))
+        else:
+            log.debug("<-- [%.6f] %s" % (elapsed, responsedata))
+        return response, http_response.status
+
+    def __truediv__(self, relative_uri):
+        return AuthServiceProxy("{}/{}".format(self.__service_url, relative_uri), self._service_name, connection=self.__conn)
+
+    def _set_conn(self, connection=None):
+        port = 80 if self.__url.port is None else self.__url.port
+        if connection:
+            self.__conn = connection
+            self.timeout = connection.timeout
+        elif self.__url.scheme == 'https':
+            self.__conn = http.client.HTTPSConnection(self.__url.hostname, port, timeout=self.timeout)
+        else:
+            self.__conn = http.client.HTTPConnection(self.__url.hostname, port, timeout=self.timeout)
--- a/basicswap/contrib/test_framework/coverage.py
+++ b/basicswap/contrib/test_framework/coverage.py
@ -0,0 +1,109 @@
+#!/usr/bin/env python3
+# Copyright (c) 2015-2018 The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+"""Utilities for doing coverage analysis on the RPC interface.
+
+Provides a way to track which RPC commands are exercised during
+testing.
+"""
+
+import os
+
+
+REFERENCE_FILENAME = 'rpc_interface.txt'
+
+
+class AuthServiceProxyWrapper():
+    """
+    An object that wraps AuthServiceProxy to record specific RPC calls.
+
+    """
+    def __init__(self, auth_service_proxy_instance, coverage_logfile=None):
+        """
+        Kwargs:
+            auth_service_proxy_instance (AuthServiceProxy): the instance
+                being wrapped.
+            coverage_logfile (str): if specified, write each service_name
+                out to a file when called.
+
+        """
+        self.auth_service_proxy_instance = auth_service_proxy_instance
+        self.coverage_logfile = coverage_logfile
+
+    def __getattr__(self, name):
+        return_val = getattr(self.auth_service_proxy_instance, name)
+        if not isinstance(return_val, type(self.auth_service_proxy_instance)):
+            # If proxy getattr returned an unwrapped value, do the same here.
+            return return_val
+        return AuthServiceProxyWrapper(return_val, self.coverage_logfile)
+
+    def __call__(self, *args, **kwargs):
+        """
+        Delegates to AuthServiceProxy, then writes the particular RPC method
+        called to a file.
+
+        """
+        return_val = self.auth_service_proxy_instance.__call__(*args, **kwargs)
+        self._log_call()
+        return return_val
+
+    def _log_call(self):
+        rpc_method = self.auth_service_proxy_instance._service_name
+
+        if self.coverage_logfile:
+            with open(self.coverage_logfile, 'a+', encoding='utf8') as f:
+                f.write("%s\n" % rpc_method)
+
+    def __truediv__(self, relative_uri):
+        return AuthServiceProxyWrapper(self.auth_service_proxy_instance / relative_uri,
+                                       self.coverage_logfile)
+
+    def get_request(self, *args, **kwargs):
+        self._log_call()
+        return self.auth_service_proxy_instance.get_request(*args, **kwargs)
+
+def get_filename(dirname, n_node):
+    """
+    Get a filename unique to the test process ID and node.
+
+    This file will contain a list of RPC commands covered.
+    """
+    pid = str(os.getpid())
+    return os.path.join(
+        dirname, "coverage.pid%s.node%s.txt" % (pid, str(n_node)))
+
+
+def write_all_rpc_commands(dirname, node):
+    """
+    Write out a list of all RPC functions available in `bitcoin-cli` for
+    coverage comparison. This will only happen once per coverage
+    directory.
+
+    Args:
+        dirname (str): temporary test dir
+        node (AuthServiceProxy): client
+
+    Returns:
+        bool. if the RPC interface file was written.
+
+    """
+    filename = os.path.join(dirname, REFERENCE_FILENAME)
+
+    if os.path.isfile(filename):
+        return False
+
+    help_output = node.help().split('\n')
+    commands = set()
+
+    for line in help_output:
+        line = line.strip()
+
+        # Ignore blanks and headers
+        if line and not line.startswith('='):
+            commands.add("%s\n" % line.split()[0])
+
+    with open(filename, 'w', encoding='utf8') as f:
+        f.writelines(list(commands))
+
+    return True
--- a/basicswap/contrib/test_framework/key.py
+++ b/basicswap/contrib/test_framework/key.py
@ -0,0 +1,393 @@
+# Copyright (c) 2019 Pieter Wuille
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+"""Test-only secp256k1 elliptic curve implementation
+
+WARNING: This code is slow, uses bad randomness, does not properly protect
+keys, and is trivially vulnerable to side channel attacks. Do not use for
+anything but tests."""
+import random
+
+def modinv(a, n):
+    """Compute the modular inverse of a modulo n
+
+    See https://en.wikipedia.org/wiki/Extended_Euclidean_algorithm#Modular_integers.
+    """
+    t1, t2 = 0, 1
+    r1, r2 = n, a
+    while r2 != 0:
+        q = r1 // r2
+        t1, t2 = t2, t1 - q * t2
+        r1, r2 = r2, r1 - q * r2
+    if r1 > 1:
+        return None
+    if t1 < 0:
+        t1 += n
+    return t1
+
+def jacobi_symbol(n, k):
+    """Compute the Jacobi symbol of n modulo k
+
+    See http://en.wikipedia.org/wiki/Jacobi_symbol
+
+    For our application k is always prime, so this is the same as the Legendre symbol."""
+    assert k > 0 and k & 1, "jacobi symbol is only defined for positive odd k"
+    n %= k
+    t = 0
+    while n != 0:
+        while n & 1 == 0:
+            n >>= 1
+            r = k & 7
+            t ^= (r == 3 or r == 5)
+        n, k = k, n
+        t ^= (n & k & 3 == 3)
+        n = n % k
+    if k == 1:
+        return -1 if t else 1
+    return 0
+
+def modsqrt(a, p):
+    """Compute the square root of a modulo p when p % 4 = 3.
+
+    The Tonelli-Shanks algorithm can be used. See https://en.wikipedia.org/wiki/Tonelli-Shanks_algorithm
+
+    Limiting this function to only work for p % 4 = 3 means we don't need to
+    iterate through the loop. The highest n such that p - 1 = 2^n Q with Q odd
+    is n = 1. Therefore Q = (p-1)/2 and sqrt = a^((Q+1)/2) = a^((p+1)/4)
+
+    secp256k1's is defined over field of size 2**256 - 2**32 - 977, which is 3 mod 4.
+    """
+    if p % 4 != 3:
+        raise NotImplementedError("modsqrt only implemented for p % 4 = 3")
+    sqrt = pow(a, (p + 1)//4, p)
+    if pow(sqrt, 2, p) == a % p:
+        return sqrt
+    return None
+
+class EllipticCurve:
+    def __init__(self, p, a, b):
+        """Initialize elliptic curve y^2 = x^3 + a*x + b over GF(p)."""
+        self.p = p
+        self.a = a % p
+        self.b = b % p
+
+    def affine(self, p1):
+        """Convert a Jacobian point tuple p1 to affine form, or None if at infinity.
+
+        An affine point is represented as the Jacobian (x, y, 1)"""
+        x1, y1, z1 = p1
+        if z1 == 0:
+            return None
+        inv = modinv(z1, self.p)
+        inv_2 = (inv**2) % self.p
+        inv_3 = (inv_2 * inv) % self.p
+        return ((inv_2 * x1) % self.p, (inv_3 * y1) % self.p, 1)
+
+    def negate(self, p1):
+        """Negate a Jacobian point tuple p1."""
+        x1, y1, z1 = p1
+        return (x1, (self.p - y1) % self.p, z1)
+
+    def on_curve(self, p1):
+        """Determine whether a Jacobian tuple p is on the curve (and not infinity)"""
+        x1, y1, z1 = p1
+        z2 = pow(z1, 2, self.p)
+        z4 = pow(z2, 2, self.p)
+        return z1 != 0 and (pow(x1, 3, self.p) + self.a * x1 * z4 + self.b * z2 * z4 - pow(y1, 2, self.p)) % self.p == 0
+
+    def is_x_coord(self, x):
+        """Test whether x is a valid X coordinate on the curve."""
+        x_3 = pow(x, 3, self.p)
+        return jacobi_symbol(x_3 + self.a * x + self.b, self.p) != -1
+
+    def lift_x(self, x):
+        """Given an X coordinate on the curve, return a corresponding affine point."""
+        x_3 = pow(x, 3, self.p)
+        v = x_3 + self.a * x + self.b
+        y = modsqrt(v, self.p)
+        if y is None:
+            return None
+        return (x, y, 1)
+
+    def double(self, p1):
+        """Double a Jacobian tuple p1
+
+        See https://en.wikibooks.org/wiki/Cryptography/Prime_Curve/Jacobian_Coordinates - Point Doubling"""
+        x1, y1, z1 = p1
+        if z1 == 0:
+            return (0, 1, 0)
+        y1_2 = (y1**2) % self.p
+        y1_4 = (y1_2**2) % self.p
+        x1_2 = (x1**2) % self.p
+        s = (4*x1*y1_2) % self.p
+        m = 3*x1_2
+        if self.a:
+            m += self.a * pow(z1, 4, self.p)
+        m = m % self.p
+        x2 = (m**2 - 2*s) % self.p
+        y2 = (m*(s - x2) - 8*y1_4) % self.p
+        z2 = (2*y1*z1) % self.p
+        return (x2, y2, z2)
+
+    def add_mixed(self, p1, p2):
+        """Add a Jacobian tuple p1 and an affine tuple p2
+
+        See https://en.wikibooks.org/wiki/Cryptography/Prime_Curve/Jacobian_Coordinates - Point Addition (with affine point)"""
+        x1, y1, z1 = p1
+        x2, y2, z2 = p2
+        assert(z2 == 1)
+        # Adding to the point at infinity is a no-op
+        if z1 == 0:
+            return p2
+        z1_2 = (z1**2) % self.p
+        z1_3 = (z1_2 * z1) % self.p
+        u2 = (x2 * z1_2) % self.p
+        s2 = (y2 * z1_3) % self.p
+        if x1 == u2:
+            if (y1 != s2):
+                # p1 and p2 are inverses. Return the point at infinity.
+                return (0, 1, 0)
+            # p1 == p2. The formulas below fail when the two points are equal.
+            return self.double(p1)
+        h = u2 - x1
+        r = s2 - y1
+        h_2 = (h**2) % self.p
+        h_3 = (h_2 * h) % self.p
+        u1_h_2 = (x1 * h_2) % self.p
+        x3 = (r**2 - h_3 - 2*u1_h_2) % self.p
+        y3 = (r*(u1_h_2 - x3) - y1*h_3) % self.p
+        z3 = (h*z1) % self.p
+        return (x3, y3, z3)
+
+    def add(self, p1, p2):
+        """Add two Jacobian tuples p1 and p2
+
+        See https://en.wikibooks.org/wiki/Cryptography/Prime_Curve/Jacobian_Coordinates - Point Addition"""
+        x1, y1, z1 = p1
+        x2, y2, z2 = p2
+        # Adding the point at infinity is a no-op
+        if z1 == 0:
+            return p2
+        if z2 == 0:
+            return p1
+        # Adding an Affine to a Jacobian is more efficient since we save field multiplications and squarings when z = 1
+        if z1 == 1:
+            return self.add_mixed(p2, p1)
+        if z2 == 1:
+            return self.add_mixed(p1, p2)
+        z1_2 = (z1**2) % self.p
+        z1_3 = (z1_2 * z1) % self.p
+        z2_2 = (z2**2) % self.p
+        z2_3 = (z2_2 * z2) % self.p
+        u1 = (x1 * z2_2) % self.p
+        u2 = (x2 * z1_2) % self.p
+        s1 = (y1 * z2_3) % self.p
+        s2 = (y2 * z1_3) % self.p
+        if u1 == u2:
+            if (s1 != s2):
+                # p1 and p2 are inverses. Return the point at infinity.
+                return (0, 1, 0)
+            # p1 == p2. The formulas below fail when the two points are equal.
+            return self.double(p1)
+        h = u2 - u1
+        r = s2 - s1
+        h_2 = (h**2) % self.p
+        h_3 = (h_2 * h) % self.p
+        u1_h_2 = (u1 * h_2) % self.p
+        x3 = (r**2 - h_3 - 2*u1_h_2) % self.p
+        y3 = (r*(u1_h_2 - x3) - s1*h_3) % self.p
+        z3 = (h*z1*z2) % self.p
+        return (x3, y3, z3)
+
+    def mul(self, ps):
+        """Compute a (multi) point multiplication
+
+        ps is a list of (Jacobian tuple, scalar) pairs.
+        """
+        r = (0, 1, 0)
+        for i in range(255, -1, -1):
+            r = self.double(r)
+            for (p, n) in ps:
+                if ((n >> i) & 1):
+                    r = self.add(r, p)
+        return r
+
+SECP256K1 = EllipticCurve(2**256 - 2**32 - 977, 0, 7)
+SECP256K1_G = (0x79BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798, 0x483ADA7726A3C4655DA4FBFC0E1108A8FD17B448A68554199C47D08FFB10D4B8, 1)
+SECP256K1_ORDER = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141
+SECP256K1_ORDER_HALF = SECP256K1_ORDER // 2
+
+class ECPubKey():
+    """A secp256k1 public key"""
+
+    def __init__(self):
+        """Construct an uninitialized public key"""
+        self.valid = False
+
+    def set_int(self, x, y):
+        p = (x, y, 1)
+        self.valid = SECP256K1.on_curve(p)
+        if self.valid:
+            self.p = p
+            self.compressed = False
+
+    def set(self, data):
+        """Construct a public key from a serialization in compressed or uncompressed format"""
+        if (len(data) == 65 and data[0] == 0x04):
+            p = (int.from_bytes(data[1:33], 'big'), int.from_bytes(data[33:65], 'big'), 1)
+            self.valid = SECP256K1.on_curve(p)
+            if self.valid:
+                self.p = p
+                self.compressed = False
+        elif (len(data) == 33 and (data[0] == 0x02 or data[0] == 0x03)):
+            x = int.from_bytes(data[1:33], 'big')
+            if SECP256K1.is_x_coord(x):
+                p = SECP256K1.lift_x(x)
+                # if the oddness of the y co-ord isn't correct, find the other
+                # valid y
+                if (p[1] & 1) != (data[0] & 1):
+                    p = SECP256K1.negate(p)
+                self.p = p
+                self.valid = True
+                self.compressed = True
+            else:
+                self.valid = False
+        else:
+            self.valid = False
+
+    @property
+    def is_compressed(self):
+        return self.compressed
+
+    @property
+    def is_valid(self):
+        return self.valid
+
+    def get_bytes(self):
+        assert(self.valid)
+        p = SECP256K1.affine(self.p)
+        if p is None:
+            return None
+        if self.compressed:
+            return bytes([0x02 + (p[1] & 1)]) + p[0].to_bytes(32, 'big')
+        else:
+            return bytes([0x04]) + p[0].to_bytes(32, 'big') + p[1].to_bytes(32, 'big')
+
+    def verify_ecdsa(self, sig, msg, low_s=True):
+        """Verify a strictly DER-encoded ECDSA signature against this pubkey.
+
+        See https://en.wikipedia.org/wiki/Elliptic_Curve_Digital_Signature_Algorithm for the
+        ECDSA verifier algorithm"""
+        assert(self.valid)
+
+        # Extract r and s from the DER formatted signature. Return false for
+        # any DER encoding errors.
+        if (sig[1] + 2 != len(sig)):
+            return False
+        if (len(sig) < 4):
+            return False
+        if (sig[0] != 0x30):
+            return False
+        if (sig[2] != 0x02):
+            return False
+        rlen = sig[3]
+        if (len(sig) < 6 + rlen):
+            return False
+        if rlen < 1 or rlen > 33:
+            return False
+        if sig[4] >= 0x80:
+            return False
+        if (rlen > 1 and (sig[4] == 0) and not (sig[5] & 0x80)):
+            return False
+        r = int.from_bytes(sig[4:4+rlen], 'big')
+        if (sig[4+rlen] != 0x02):
+            return False
+        slen = sig[5+rlen]
+        if slen < 1 or slen > 33:
+            return False
+        if (len(sig) != 6 + rlen + slen):
+            return False
+        if sig[6+rlen] >= 0x80:
+            return False
+        if (slen > 1 and (sig[6+rlen] == 0) and not (sig[7+rlen] & 0x80)):
+            return False
+        s = int.from_bytes(sig[6+rlen:6+rlen+slen], 'big')
+
+        # Verify that r and s are within the group order
+        if r < 1 or s < 1 or r >= SECP256K1_ORDER or s >= SECP256K1_ORDER:
+            return False
+        if low_s and s >= SECP256K1_ORDER_HALF:
+            return False
+        z = int.from_bytes(msg, 'big')
+
+        # Run verifier algorithm on r, s
+        w = modinv(s, SECP256K1_ORDER)
+        u1 = z*w % SECP256K1_ORDER
+        u2 = r*w % SECP256K1_ORDER
+        R = SECP256K1.affine(SECP256K1.mul([(SECP256K1_G, u1), (self.p, u2)]))
+        if R is None or R[0] != r:
+            return False
+        return True
+
+class ECKey():
+    """A secp256k1 private key"""
+
+    def __init__(self):
+        self.valid = False
+
+    def set(self, secret, compressed):
+        """Construct a private key object with given 32-byte secret and compressed flag."""
+        assert(len(secret) == 32)
+        secret = int.from_bytes(secret, 'big')
+        self.valid = (secret > 0 and secret < SECP256K1_ORDER)
+        if self.valid:
+            self.secret = secret
+            self.compressed = compressed
+
+    def generate(self, compressed=True):
+        """Generate a random private key (compressed or uncompressed)."""
+        self.set(random.randrange(1, SECP256K1_ORDER).to_bytes(32, 'big'), compressed)
+
+    def get_bytes(self):
+        """Retrieve the 32-byte representation of this key."""
+        assert(self.valid)
+        return self.secret.to_bytes(32, 'big')
+
+    @property
+    def is_valid(self):
+        return self.valid
+
+    @property
+    def is_compressed(self):
+        return self.compressed
+
+    def get_pubkey(self):
+        """Compute an ECPubKey object for this secret key."""
+        assert(self.valid)
+        ret = ECPubKey()
+        p = SECP256K1.mul([(SECP256K1_G, self.secret)])
+        ret.p = p
+        ret.valid = True
+        ret.compressed = self.compressed
+        return ret
+
+    def sign_ecdsa(self, msg, low_s=True):
+        """Construct a DER-encoded ECDSA signature with this key.
+
+        See https://en.wikipedia.org/wiki/Elliptic_Curve_Digital_Signature_Algorithm for the
+        ECDSA signer algorithm."""
+        assert(self.valid)
+        z = int.from_bytes(msg, 'big')
+        # Note: no RFC6979, but a simple random nonce (some tests rely on distinct transactions for the same operation)
+        k = random.randrange(1, SECP256K1_ORDER)
+        R = SECP256K1.affine(SECP256K1.mul([(SECP256K1_G, k)]))
+        r = R[0] % SECP256K1_ORDER
+        s = (modinv(k, SECP256K1_ORDER) * (z + self.secret * r)) % SECP256K1_ORDER
+        if low_s and s > SECP256K1_ORDER_HALF:
+            s = SECP256K1_ORDER - s
+        # Represent in DER format. The byte representations of r and s have
+        # length rounded up (255 bits becomes 32 bytes and 256 bits becomes 33
+        # bytes).
+        rb = r.to_bytes((r.bit_length() + 8) // 8, 'big')
+        sb = s.to_bytes((s.bit_length() + 8) // 8, 'big')
+        return b'\x30' + bytes([4 + len(rb) + len(sb), 2, len(rb)]) + rb + bytes([2, len(sb)]) + sb
--- a/basicswap/contrib/test_framework/messages.py
+++ b/basicswap/contrib/test_framework/messages.py
--- a/basicswap/contrib/test_framework/script.py
+++ b/basicswap/contrib/test_framework/script.py
@ -0,0 +1,740 @@
+#!/usr/bin/env python3
+# Copyright (c) 2015-2020 The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+"""Functionality to build scripts, as well as signature hash functions.
+
+This file is modified from python-bitcoinlib.
+"""
+import hashlib
+import struct
+import unittest
+from typing import List, Dict
+
+from .messages import (
+    CTransaction,
+    CTxOut,
+    hash256,
+    ser_string,
+    ser_uint256,
+    sha256,
+    uint256_from_str,
+)
+
+MAX_SCRIPT_ELEMENT_SIZE = 520
+OPCODE_NAMES = {}  # type: Dict[CScriptOp, str]
+
+def hash160(s):
+    return hashlib.new('ripemd160', sha256(s)).digest()
+
+def bn2vch(v):
+    """Convert number to bitcoin-specific little endian format."""
+    # We need v.bit_length() bits, plus a sign bit for every nonzero number.
+    n_bits = v.bit_length() + (v != 0)
+    # The number of bytes for that is:
+    n_bytes = (n_bits + 7) // 8
+    # Convert number to absolute value + sign in top bit.
+    encoded_v = 0 if v == 0 else abs(v) | ((v < 0) << (n_bytes * 8 - 1))
+    # Serialize to bytes
+    return encoded_v.to_bytes(n_bytes, 'little')
+
+_opcode_instances = []  # type: List[CScriptOp]
+class CScriptOp(int):
+    """A single script opcode"""
+    __slots__ = ()
+
+    @staticmethod
+    def encode_op_pushdata(d):
+        """Encode a PUSHDATA op, returning bytes"""
+        if len(d) < 0x4c:
+            return b'' + bytes([len(d)]) + d  # OP_PUSHDATA
+        elif len(d) <= 0xff:
+            return b'\x4c' + bytes([len(d)]) + d  # OP_PUSHDATA1
+        elif len(d) <= 0xffff:
+            return b'\x4d' + struct.pack(b'<H', len(d)) + d  # OP_PUSHDATA2
+        elif len(d) <= 0xffffffff:
+            return b'\x4e' + struct.pack(b'<I', len(d)) + d  # OP_PUSHDATA4
+        else:
+            raise ValueError("Data too long to encode in a PUSHDATA op")
+
+    @staticmethod
+    def encode_op_n(n):
+        """Encode a small integer op, returning an opcode"""
+        if not (0 <= n <= 16):
+            raise ValueError('Integer must be in range 0 <= n <= 16, got %d' % n)
+
+        if n == 0:
+            return OP_0
+        else:
+            return CScriptOp(OP_1 + n - 1)
+
+    def decode_op_n(self):
+        """Decode a small integer opcode, returning an integer"""
+        if self == OP_0:
+            return 0
+
+        if not (self == OP_0 or OP_1 <= self <= OP_16):
+            raise ValueError('op %r is not an OP_N' % self)
+
+        return int(self - OP_1 + 1)
+
+    def is_small_int(self):
+        """Return true if the op pushes a small integer to the stack"""
+        if 0x51 <= self <= 0x60 or self == 0:
+            return True
+        else:
+            return False
+
+    def __str__(self):
+        return repr(self)
+
+    def __repr__(self):
+        if self in OPCODE_NAMES:
+            return OPCODE_NAMES[self]
+        else:
+            return 'CScriptOp(0x%x)' % self
+
+    def __new__(cls, n):
+        try:
+            return _opcode_instances[n]
+        except IndexError:
+            assert len(_opcode_instances) == n
+            _opcode_instances.append(super().__new__(cls, n))
+            return _opcode_instances[n]
+
+# Populate opcode instance table
+for n in range(0xff + 1):
+    CScriptOp(n)
+
+
+# push value
+OP_0 = CScriptOp(0x00)
+OP_FALSE = OP_0
+OP_PUSHDATA1 = CScriptOp(0x4c)
+OP_PUSHDATA2 = CScriptOp(0x4d)
+OP_PUSHDATA4 = CScriptOp(0x4e)
+OP_1NEGATE = CScriptOp(0x4f)
+OP_RESERVED = CScriptOp(0x50)
+OP_1 = CScriptOp(0x51)
+OP_TRUE = OP_1
+OP_2 = CScriptOp(0x52)
+OP_3 = CScriptOp(0x53)
+OP_4 = CScriptOp(0x54)
+OP_5 = CScriptOp(0x55)
+OP_6 = CScriptOp(0x56)
+OP_7 = CScriptOp(0x57)
+OP_8 = CScriptOp(0x58)
+OP_9 = CScriptOp(0x59)
+OP_10 = CScriptOp(0x5a)
+OP_11 = CScriptOp(0x5b)
+OP_12 = CScriptOp(0x5c)
+OP_13 = CScriptOp(0x5d)
+OP_14 = CScriptOp(0x5e)
+OP_15 = CScriptOp(0x5f)
+OP_16 = CScriptOp(0x60)
+
+# control
+OP_NOP = CScriptOp(0x61)
+OP_VER = CScriptOp(0x62)
+OP_IF = CScriptOp(0x63)
+OP_NOTIF = CScriptOp(0x64)
+OP_VERIF = CScriptOp(0x65)
+OP_VERNOTIF = CScriptOp(0x66)
+OP_ELSE = CScriptOp(0x67)
+OP_ENDIF = CScriptOp(0x68)
+OP_VERIFY = CScriptOp(0x69)
+OP_RETURN = CScriptOp(0x6a)
+
+# stack ops
+OP_TOALTSTACK = CScriptOp(0x6b)
+OP_FROMALTSTACK = CScriptOp(0x6c)
+OP_2DROP = CScriptOp(0x6d)
+OP_2DUP = CScriptOp(0x6e)
+OP_3DUP = CScriptOp(0x6f)
+OP_2OVER = CScriptOp(0x70)
+OP_2ROT = CScriptOp(0x71)
+OP_2SWAP = CScriptOp(0x72)
+OP_IFDUP = CScriptOp(0x73)
+OP_DEPTH = CScriptOp(0x74)
+OP_DROP = CScriptOp(0x75)
+OP_DUP = CScriptOp(0x76)
+OP_NIP = CScriptOp(0x77)
+OP_OVER = CScriptOp(0x78)
+OP_PICK = CScriptOp(0x79)
+OP_ROLL = CScriptOp(0x7a)
+OP_ROT = CScriptOp(0x7b)
+OP_SWAP = CScriptOp(0x7c)
+OP_TUCK = CScriptOp(0x7d)
+
+# splice ops
+OP_CAT = CScriptOp(0x7e)
+OP_SUBSTR = CScriptOp(0x7f)
+OP_LEFT = CScriptOp(0x80)
+OP_RIGHT = CScriptOp(0x81)
+OP_SIZE = CScriptOp(0x82)
+
+# bit logic
+OP_INVERT = CScriptOp(0x83)
+OP_AND = CScriptOp(0x84)
+OP_OR = CScriptOp(0x85)
+OP_XOR = CScriptOp(0x86)
+OP_EQUAL = CScriptOp(0x87)
+OP_EQUALVERIFY = CScriptOp(0x88)
+OP_RESERVED1 = CScriptOp(0x89)
+OP_RESERVED2 = CScriptOp(0x8a)
+
+# numeric
+OP_1ADD = CScriptOp(0x8b)
+OP_1SUB = CScriptOp(0x8c)
+OP_2MUL = CScriptOp(0x8d)
+OP_2DIV = CScriptOp(0x8e)
+OP_NEGATE = CScriptOp(0x8f)
+OP_ABS = CScriptOp(0x90)
+OP_NOT = CScriptOp(0x91)
+OP_0NOTEQUAL = CScriptOp(0x92)
+
+OP_ADD = CScriptOp(0x93)
+OP_SUB = CScriptOp(0x94)
+OP_MUL = CScriptOp(0x95)
+OP_DIV = CScriptOp(0x96)
+OP_MOD = CScriptOp(0x97)
+OP_LSHIFT = CScriptOp(0x98)
+OP_RSHIFT = CScriptOp(0x99)
+
+OP_BOOLAND = CScriptOp(0x9a)
+OP_BOOLOR = CScriptOp(0x9b)
+OP_NUMEQUAL = CScriptOp(0x9c)
+OP_NUMEQUALVERIFY = CScriptOp(0x9d)
+OP_NUMNOTEQUAL = CScriptOp(0x9e)
+OP_LESSTHAN = CScriptOp(0x9f)
+OP_GREATERTHAN = CScriptOp(0xa0)
+OP_LESSTHANOREQUAL = CScriptOp(0xa1)
+OP_GREATERTHANOREQUAL = CScriptOp(0xa2)
+OP_MIN = CScriptOp(0xa3)
+OP_MAX = CScriptOp(0xa4)
+
+OP_WITHIN = CScriptOp(0xa5)
+
+# crypto
+OP_RIPEMD160 = CScriptOp(0xa6)
+OP_SHA1 = CScriptOp(0xa7)
+OP_SHA256 = CScriptOp(0xa8)
+OP_HASH160 = CScriptOp(0xa9)
+OP_HASH256 = CScriptOp(0xaa)
+OP_CODESEPARATOR = CScriptOp(0xab)
+OP_CHECKSIG = CScriptOp(0xac)
+OP_CHECKSIGVERIFY = CScriptOp(0xad)
+OP_CHECKMULTISIG = CScriptOp(0xae)
+OP_CHECKMULTISIGVERIFY = CScriptOp(0xaf)
+
+# expansion
+OP_NOP1 = CScriptOp(0xb0)
+OP_CHECKLOCKTIMEVERIFY = CScriptOp(0xb1)
+OP_CHECKSEQUENCEVERIFY = CScriptOp(0xb2)
+OP_NOP4 = CScriptOp(0xb3)
+OP_NOP5 = CScriptOp(0xb4)
+OP_NOP6 = CScriptOp(0xb5)
+OP_NOP7 = CScriptOp(0xb6)
+OP_NOP8 = CScriptOp(0xb7)
+OP_NOP9 = CScriptOp(0xb8)
+OP_NOP10 = CScriptOp(0xb9)
+
+# template matching params
+OP_SMALLINTEGER = CScriptOp(0xfa)
+OP_PUBKEYS = CScriptOp(0xfb)
+OP_PUBKEYHASH = CScriptOp(0xfd)
+OP_PUBKEY = CScriptOp(0xfe)
+
+OP_INVALIDOPCODE = CScriptOp(0xff)
+
+OPCODE_NAMES.update({
+    OP_0: 'OP_0',
+    OP_PUSHDATA1: 'OP_PUSHDATA1',
+    OP_PUSHDATA2: 'OP_PUSHDATA2',
+    OP_PUSHDATA4: 'OP_PUSHDATA4',
+    OP_1NEGATE: 'OP_1NEGATE',
+    OP_RESERVED: 'OP_RESERVED',
+    OP_1: 'OP_1',
+    OP_2: 'OP_2',
+    OP_3: 'OP_3',
+    OP_4: 'OP_4',
+    OP_5: 'OP_5',
+    OP_6: 'OP_6',
+    OP_7: 'OP_7',
+    OP_8: 'OP_8',
+    OP_9: 'OP_9',
+    OP_10: 'OP_10',
+    OP_11: 'OP_11',
+    OP_12: 'OP_12',
+    OP_13: 'OP_13',
+    OP_14: 'OP_14',
+    OP_15: 'OP_15',
+    OP_16: 'OP_16',
+    OP_NOP: 'OP_NOP',
+    OP_VER: 'OP_VER',
+    OP_IF: 'OP_IF',
+    OP_NOTIF: 'OP_NOTIF',
+    OP_VERIF: 'OP_VERIF',
+    OP_VERNOTIF: 'OP_VERNOTIF',
+    OP_ELSE: 'OP_ELSE',
+    OP_ENDIF: 'OP_ENDIF',
+    OP_VERIFY: 'OP_VERIFY',
+    OP_RETURN: 'OP_RETURN',
+    OP_TOALTSTACK: 'OP_TOALTSTACK',
+    OP_FROMALTSTACK: 'OP_FROMALTSTACK',
+    OP_2DROP: 'OP_2DROP',
+    OP_2DUP: 'OP_2DUP',
+    OP_3DUP: 'OP_3DUP',
+    OP_2OVER: 'OP_2OVER',
+    OP_2ROT: 'OP_2ROT',
+    OP_2SWAP: 'OP_2SWAP',
+    OP_IFDUP: 'OP_IFDUP',
+    OP_DEPTH: 'OP_DEPTH',
+    OP_DROP: 'OP_DROP',
+    OP_DUP: 'OP_DUP',
+    OP_NIP: 'OP_NIP',
+    OP_OVER: 'OP_OVER',
+    OP_PICK: 'OP_PICK',
+    OP_ROLL: 'OP_ROLL',
+    OP_ROT: 'OP_ROT',
+    OP_SWAP: 'OP_SWAP',
+    OP_TUCK: 'OP_TUCK',
+    OP_CAT: 'OP_CAT',
+    OP_SUBSTR: 'OP_SUBSTR',
+    OP_LEFT: 'OP_LEFT',
+    OP_RIGHT: 'OP_RIGHT',
+    OP_SIZE: 'OP_SIZE',
+    OP_INVERT: 'OP_INVERT',
+    OP_AND: 'OP_AND',
+    OP_OR: 'OP_OR',
+    OP_XOR: 'OP_XOR',
+    OP_EQUAL: 'OP_EQUAL',
+    OP_EQUALVERIFY: 'OP_EQUALVERIFY',
+    OP_RESERVED1: 'OP_RESERVED1',
+    OP_RESERVED2: 'OP_RESERVED2',
+    OP_1ADD: 'OP_1ADD',
+    OP_1SUB: 'OP_1SUB',
+    OP_2MUL: 'OP_2MUL',
+    OP_2DIV: 'OP_2DIV',
+    OP_NEGATE: 'OP_NEGATE',
+    OP_ABS: 'OP_ABS',
+    OP_NOT: 'OP_NOT',
+    OP_0NOTEQUAL: 'OP_0NOTEQUAL',
+    OP_ADD: 'OP_ADD',
+    OP_SUB: 'OP_SUB',
+    OP_MUL: 'OP_MUL',
+    OP_DIV: 'OP_DIV',
+    OP_MOD: 'OP_MOD',
+    OP_LSHIFT: 'OP_LSHIFT',
+    OP_RSHIFT: 'OP_RSHIFT',
+    OP_BOOLAND: 'OP_BOOLAND',
+    OP_BOOLOR: 'OP_BOOLOR',
+    OP_NUMEQUAL: 'OP_NUMEQUAL',
+    OP_NUMEQUALVERIFY: 'OP_NUMEQUALVERIFY',
+    OP_NUMNOTEQUAL: 'OP_NUMNOTEQUAL',
+    OP_LESSTHAN: 'OP_LESSTHAN',
+    OP_GREATERTHAN: 'OP_GREATERTHAN',
+    OP_LESSTHANOREQUAL: 'OP_LESSTHANOREQUAL',
+    OP_GREATERTHANOREQUAL: 'OP_GREATERTHANOREQUAL',
+    OP_MIN: 'OP_MIN',
+    OP_MAX: 'OP_MAX',
+    OP_WITHIN: 'OP_WITHIN',
+    OP_RIPEMD160: 'OP_RIPEMD160',
+    OP_SHA1: 'OP_SHA1',
+    OP_SHA256: 'OP_SHA256',
+    OP_HASH160: 'OP_HASH160',
+    OP_HASH256: 'OP_HASH256',
+    OP_CODESEPARATOR: 'OP_CODESEPARATOR',
+    OP_CHECKSIG: 'OP_CHECKSIG',
+    OP_CHECKSIGVERIFY: 'OP_CHECKSIGVERIFY',
+    OP_CHECKMULTISIG: 'OP_CHECKMULTISIG',
+    OP_CHECKMULTISIGVERIFY: 'OP_CHECKMULTISIGVERIFY',
+    OP_NOP1: 'OP_NOP1',
+    OP_CHECKLOCKTIMEVERIFY: 'OP_CHECKLOCKTIMEVERIFY',
+    OP_CHECKSEQUENCEVERIFY: 'OP_CHECKSEQUENCEVERIFY',
+    OP_NOP4: 'OP_NOP4',
+    OP_NOP5: 'OP_NOP5',
+    OP_NOP6: 'OP_NOP6',
+    OP_NOP7: 'OP_NOP7',
+    OP_NOP8: 'OP_NOP8',
+    OP_NOP9: 'OP_NOP9',
+    OP_NOP10: 'OP_NOP10',
+    OP_SMALLINTEGER: 'OP_SMALLINTEGER',
+    OP_PUBKEYS: 'OP_PUBKEYS',
+    OP_PUBKEYHASH: 'OP_PUBKEYHASH',
+    OP_PUBKEY: 'OP_PUBKEY',
+    OP_INVALIDOPCODE: 'OP_INVALIDOPCODE',
+})
+
+class CScriptInvalidError(Exception):
+    """Base class for CScript exceptions"""
+    pass
+
+class CScriptTruncatedPushDataError(CScriptInvalidError):
+    """Invalid pushdata due to truncation"""
+    def __init__(self, msg, data):
+        self.data = data
+        super().__init__(msg)
+
+
+# This is used, eg, for blockchain heights in coinbase scripts (bip34)
+class CScriptNum:
+    __slots__ = ("value",)
+
+    def __init__(self, d=0):
+        self.value = d
+
+    @staticmethod
+    def encode(obj):
+        r = bytearray(0)
+        if obj.value == 0:
+            return bytes(r)
+        neg = obj.value < 0
+        absvalue = -obj.value if neg else obj.value
+        while (absvalue):
+            r.append(absvalue & 0xff)
+            absvalue >>= 8
+        if r[-1] & 0x80:
+            r.append(0x80 if neg else 0)
+        elif neg:
+            r[-1] |= 0x80
+        return bytes([len(r)]) + r
+
+    @staticmethod
+    def decode(vch):
+        result = 0
+        # We assume valid push_size and minimal encoding
+        value = vch[1:]
+        if len(value) == 0:
+            return result
+        for i, byte in enumerate(value):
+            result |= int(byte) << 8 * i
+        if value[-1] >= 0x80:
+            # Mask for all but the highest result bit
+            num_mask = (2**(len(value) * 8) - 1) >> 1
+            result &= num_mask
+            result *= -1
+        return result
+
+
+class CScript(bytes):
+    """Serialized script
+
+    A bytes subclass, so you can use this directly whenever bytes are accepted.
+    Note that this means that indexing does *not* work - you'll get an index by
+    byte rather than opcode. This format was chosen for efficiency so that the
+    general case would not require creating a lot of little CScriptOP objects.
+
+    iter(script) however does iterate by opcode.
+    """
+    __slots__ = ()
+
+    @classmethod
+    def __coerce_instance(cls, other):
+        # Coerce other into bytes
+        if isinstance(other, CScriptOp):
+            other = bytes([other])
+        elif isinstance(other, CScriptNum):
+            if (other.value == 0):
+                other = bytes([CScriptOp(OP_0)])
+            else:
+                other = CScriptNum.encode(other)
+        elif isinstance(other, int):
+            if 0 <= other <= 16:
+                other = bytes([CScriptOp.encode_op_n(other)])
+            elif other == -1:
+                other = bytes([OP_1NEGATE])
+            else:
+                other = CScriptOp.encode_op_pushdata(bn2vch(other))
+        elif isinstance(other, (bytes, bytearray)):
+            other = CScriptOp.encode_op_pushdata(other)
+        return other
+
+    def __add__(self, other):
+        # add makes no sense for a CScript()
+        raise NotImplementedError
+
+    def join(self, iterable):
+        # join makes no sense for a CScript()
+        raise NotImplementedError
+
+    def __new__(cls, value=b''):
+        if isinstance(value, bytes) or isinstance(value, bytearray):
+            return super().__new__(cls, value)
+        else:
+            def coerce_iterable(iterable):
+                for instance in iterable:
+                    yield cls.__coerce_instance(instance)
+            # Annoyingly on both python2 and python3 bytes.join() always
+            # returns a bytes instance even when subclassed.
+            return super().__new__(cls, b''.join(coerce_iterable(value)))
+
+    def raw_iter(self):
+        """Raw iteration
+
+        Yields tuples of (opcode, data, sop_idx) so that the different possible
+        PUSHDATA encodings can be accurately distinguished, as well as
+        determining the exact opcode byte indexes. (sop_idx)
+        """
+        i = 0
+        while i < len(self):
+            sop_idx = i
+            opcode = self[i]
+            i += 1
+
+            if opcode > OP_PUSHDATA4:
+                yield (opcode, None, sop_idx)
+            else:
+                datasize = None
+                pushdata_type = None
+                if opcode < OP_PUSHDATA1:
+                    pushdata_type = 'PUSHDATA(%d)' % opcode
+                    datasize = opcode
+
+                elif opcode == OP_PUSHDATA1:
+                    pushdata_type = 'PUSHDATA1'
+                    if i >= len(self):
+                        raise CScriptInvalidError('PUSHDATA1: missing data length')
+                    datasize = self[i]
+                    i += 1
+
+                elif opcode == OP_PUSHDATA2:
+                    pushdata_type = 'PUSHDATA2'
+                    if i + 1 >= len(self):
+                        raise CScriptInvalidError('PUSHDATA2: missing data length')
+                    datasize = self[i] + (self[i + 1] << 8)
+                    i += 2
+
+                elif opcode == OP_PUSHDATA4:
+                    pushdata_type = 'PUSHDATA4'
+                    if i + 3 >= len(self):
+                        raise CScriptInvalidError('PUSHDATA4: missing data length')
+                    datasize = self[i] + (self[i + 1] << 8) + (self[i + 2] << 16) + (self[i + 3] << 24)
+                    i += 4
+
+                else:
+                    assert False  # shouldn't happen
+
+                data = bytes(self[i:i + datasize])
+
+                # Check for truncation
+                if len(data) < datasize:
+                    raise CScriptTruncatedPushDataError('%s: truncated data' % pushdata_type, data)
+
+                i += datasize
+
+                yield (opcode, data, sop_idx)
+
+    def __iter__(self):
+        """'Cooked' iteration
+
+        Returns either a CScriptOP instance, an integer, or bytes, as
+        appropriate.
+
+        See raw_iter() if you need to distinguish the different possible
+        PUSHDATA encodings.
+        """
+        for (opcode, data, sop_idx) in self.raw_iter():
+            if data is not None:
+                yield data
+            else:
+                opcode = CScriptOp(opcode)
+
+                if opcode.is_small_int():
+                    yield opcode.decode_op_n()
+                else:
+                    yield CScriptOp(opcode)
+
+    def __repr__(self):
+        def _repr(o):
+            if isinstance(o, bytes):
+                return "x('%s')" % o.hex()
+            else:
+                return repr(o)
+
+        ops = []
+        i = iter(self)
+        while True:
+            op = None
+            try:
+                op = _repr(next(i))
+            except CScriptTruncatedPushDataError as err:
+                op = '%s...<ERROR: %s>' % (_repr(err.data), err)
+                break
+            except CScriptInvalidError as err:
+                op = '<ERROR: %s>' % err
+                break
+            except StopIteration:
+                break
+            finally:
+                if op is not None:
+                    ops.append(op)
+
+        return "CScript([%s])" % ', '.join(ops)
+
+    def GetSigOpCount(self, fAccurate):
+        """Get the SigOp count.
+
+        fAccurate - Accurately count CHECKMULTISIG, see BIP16 for details.
+
+        Note that this is consensus-critical.
+        """
+        n = 0
+        lastOpcode = OP_INVALIDOPCODE
+        for (opcode, data, sop_idx) in self.raw_iter():
+            if opcode in (OP_CHECKSIG, OP_CHECKSIGVERIFY):
+                n += 1
+            elif opcode in (OP_CHECKMULTISIG, OP_CHECKMULTISIGVERIFY):
+                if fAccurate and (OP_1 <= lastOpcode <= OP_16):
+                    n += opcode.decode_op_n()
+                else:
+                    n += 20
+            lastOpcode = opcode
+        return n
+
+
+SIGHASH_ALL = 1
+SIGHASH_NONE = 2
+SIGHASH_SINGLE = 3
+SIGHASH_ANYONECANPAY = 0x80
+
+def FindAndDelete(script, sig):
+    """Consensus critical, see FindAndDelete() in Satoshi codebase"""
+    r = b''
+    last_sop_idx = sop_idx = 0
+    skip = True
+    for (opcode, data, sop_idx) in script.raw_iter():
+        if not skip:
+            r += script[last_sop_idx:sop_idx]
+        last_sop_idx = sop_idx
+        if script[sop_idx:sop_idx + len(sig)] == sig:
+            skip = True
+        else:
+            skip = False
+    if not skip:
+        r += script[last_sop_idx:]
+    return CScript(r)
+
+
+def LegacySignatureHash(script, txTo, inIdx, hashtype):
+    """Consensus-correct SignatureHash
+
+    Returns (hash, err) to precisely match the consensus-critical behavior of
+    the SIGHASH_SINGLE bug. (inIdx is *not* checked for validity)
+    """
+    HASH_ONE = b'\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+
+    if inIdx >= len(txTo.vin):
+        return (HASH_ONE, "inIdx %d out of range (%d)" % (inIdx, len(txTo.vin)))
+    txtmp = CTransaction(txTo)
+
+    for txin in txtmp.vin:
+        txin.scriptSig = b''
+    txtmp.vin[inIdx].scriptSig = FindAndDelete(script, CScript([OP_CODESEPARATOR]))
+
+    if (hashtype & 0x1f) == SIGHASH_NONE:
+        txtmp.vout = []
+
+        for i in range(len(txtmp.vin)):
+            if i != inIdx:
+                txtmp.vin[i].nSequence = 0
+
+    elif (hashtype & 0x1f) == SIGHASH_SINGLE:
+        outIdx = inIdx
+        if outIdx >= len(txtmp.vout):
+            return (HASH_ONE, "outIdx %d out of range (%d)" % (outIdx, len(txtmp.vout)))
+
+        tmp = txtmp.vout[outIdx]
+        txtmp.vout = []
+        for i in range(outIdx):
+            txtmp.vout.append(CTxOut(-1))
+        txtmp.vout.append(tmp)
+
+        for i in range(len(txtmp.vin)):
+            if i != inIdx:
+                txtmp.vin[i].nSequence = 0
+
+    if hashtype & SIGHASH_ANYONECANPAY:
+        tmp = txtmp.vin[inIdx]
+        txtmp.vin = []
+        txtmp.vin.append(tmp)
+
+    s = txtmp.serialize_without_witness()
+    s += struct.pack(b"<I", hashtype)
+
+    hash = hash256(s)
+
+    return (hash, None)
+
+# TODO: Allow cached hashPrevouts/hashSequence/hashOutputs to be provided.
+# Performance optimization probably not necessary for python tests, however.
+# Note that this corresponds to sigversion == 1 in EvalScript, which is used
+# for version 0 witnesses.
+def SegwitV0SignatureHash(script, txTo, inIdx, hashtype, amount):
+
+    hashPrevouts = 0
+    hashSequence = 0
+    hashOutputs = 0
+
+    if not (hashtype & SIGHASH_ANYONECANPAY):
+        serialize_prevouts = bytes()
+        for i in txTo.vin:
+            serialize_prevouts += i.prevout.serialize()
+        hashPrevouts = uint256_from_str(hash256(serialize_prevouts))
+
+    if (not (hashtype & SIGHASH_ANYONECANPAY) and (hashtype & 0x1f) != SIGHASH_SINGLE and (hashtype & 0x1f) != SIGHASH_NONE):
+        serialize_sequence = bytes()
+        for i in txTo.vin:
+            serialize_sequence += struct.pack("<I", i.nSequence)
+        hashSequence = uint256_from_str(hash256(serialize_sequence))
+
+    if ((hashtype & 0x1f) != SIGHASH_SINGLE and (hashtype & 0x1f) != SIGHASH_NONE):
+        serialize_outputs = bytes()
+        for o in txTo.vout:
+            serialize_outputs += o.serialize()
+        hashOutputs = uint256_from_str(hash256(serialize_outputs))
+    elif ((hashtype & 0x1f) == SIGHASH_SINGLE and inIdx < len(txTo.vout)):
+        serialize_outputs = txTo.vout[inIdx].serialize()
+        hashOutputs = uint256_from_str(hash256(serialize_outputs))
+
+    ss = bytes()
+    ss += struct.pack("<i", txTo.nVersion)
+    ss += ser_uint256(hashPrevouts)
+    ss += ser_uint256(hashSequence)
+    ss += txTo.vin[inIdx].prevout.serialize()
+    ss += ser_string(script)
+    ss += struct.pack("<q", amount)
+    ss += struct.pack("<I", txTo.vin[inIdx].nSequence)
+    ss += ser_uint256(hashOutputs)
+    ss += struct.pack("<i", txTo.nLockTime)
+    ss += struct.pack("<I", hashtype)
+
+    return hash256(ss)
+
+class TestFrameworkScript(unittest.TestCase):
+    def test_bn2vch(self):
+        self.assertEqual(bn2vch(0), bytes([]))
+        self.assertEqual(bn2vch(1), bytes([0x01]))
+        self.assertEqual(bn2vch(-1), bytes([0x81]))
+        self.assertEqual(bn2vch(0x7F), bytes([0x7F]))
+        self.assertEqual(bn2vch(-0x7F), bytes([0xFF]))
+        self.assertEqual(bn2vch(0x80), bytes([0x80, 0x00]))
+        self.assertEqual(bn2vch(-0x80), bytes([0x80, 0x80]))
+        self.assertEqual(bn2vch(0xFF), bytes([0xFF, 0x00]))
+        self.assertEqual(bn2vch(-0xFF), bytes([0xFF, 0x80]))
+        self.assertEqual(bn2vch(0x100), bytes([0x00, 0x01]))
+        self.assertEqual(bn2vch(-0x100), bytes([0x00, 0x81]))
+        self.assertEqual(bn2vch(0x7FFF), bytes([0xFF, 0x7F]))
+        self.assertEqual(bn2vch(-0x8000), bytes([0x00, 0x80, 0x80]))
+        self.assertEqual(bn2vch(-0x7FFFFF), bytes([0xFF, 0xFF, 0xFF]))
+        self.assertEqual(bn2vch(0x80000000), bytes([0x00, 0x00, 0x00, 0x80, 0x00]))
+        self.assertEqual(bn2vch(-0x80000000), bytes([0x00, 0x00, 0x00, 0x80, 0x80]))
+        self.assertEqual(bn2vch(0xFFFFFFFF), bytes([0xFF, 0xFF, 0xFF, 0xFF, 0x00]))
+        self.assertEqual(bn2vch(123456789), bytes([0x15, 0xCD, 0x5B, 0x07]))
+        self.assertEqual(bn2vch(-54321), bytes([0x31, 0xD4, 0x80]))
+
+    def test_cscriptnum_encoding(self):
+        # round-trip negative and multi-byte CScriptNums
+        values = [0, 1, -1, -2, 127, 128, -255, 256, (1 << 15) - 1, -(1 << 16), (1 << 24) - 1, (1 << 31), 1 - (1 << 32), 1 << 40, 1500, -1500]
+        for value in values:
+            self.assertEqual(CScriptNum.decode(CScriptNum.encode(CScriptNum(value))), value)
--- a/basicswap/contrib/test_framework/segwit_addr.py
+++ b/basicswap/contrib/test_framework/segwit_addr.py
@ -0,0 +1,107 @@
+#!/usr/bin/env python3
+# Copyright (c) 2017 Pieter Wuille
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+"""Reference implementation for Bech32 and segwit addresses."""
+
+
+CHARSET = "qpzry9x8gf2tvdw0s3jn54khce6mua7l"
+
+
+def bech32_polymod(values):
+    """Internal function that computes the Bech32 checksum."""
+    generator = [0x3b6a57b2, 0x26508e6d, 0x1ea119fa, 0x3d4233dd, 0x2a1462b3]
+    chk = 1
+    for value in values:
+        top = chk >> 25
+        chk = (chk & 0x1ffffff) << 5 ^ value
+        for i in range(5):
+            chk ^= generator[i] if ((top >> i) & 1) else 0
+    return chk
+
+
+def bech32_hrp_expand(hrp):
+    """Expand the HRP into values for checksum computation."""
+    return [ord(x) >> 5 for x in hrp] + [0] + [ord(x) & 31 for x in hrp]
+
+
+def bech32_verify_checksum(hrp, data):
+    """Verify a checksum given HRP and converted data characters."""
+    return bech32_polymod(bech32_hrp_expand(hrp) + data) == 1
+
+
+def bech32_create_checksum(hrp, data):
+    """Compute the checksum values given HRP and data."""
+    values = bech32_hrp_expand(hrp) + data
+    polymod = bech32_polymod(values + [0, 0, 0, 0, 0, 0]) ^ 1
+    return [(polymod >> 5 * (5 - i)) & 31 for i in range(6)]
+
+
+def bech32_encode(hrp, data):
+    """Compute a Bech32 string given HRP and data values."""
+    combined = data + bech32_create_checksum(hrp, data)
+    return hrp + '1' + ''.join([CHARSET[d] for d in combined])
+
+
+def bech32_decode(bech):
+    """Validate a Bech32 string, and determine HRP and data."""
+    if ((any(ord(x) < 33 or ord(x) > 126 for x in bech)) or
+            (bech.lower() != bech and bech.upper() != bech)):
+        return (None, None)
+    bech = bech.lower()
+    pos = bech.rfind('1')
+    if pos < 1 or pos + 7 > len(bech) or len(bech) > 90:
+        return (None, None)
+    if not all(x in CHARSET for x in bech[pos+1:]):
+        return (None, None)
+    hrp = bech[:pos]
+    data = [CHARSET.find(x) for x in bech[pos+1:]]
+    if not bech32_verify_checksum(hrp, data):
+        return (None, None)
+    return (hrp, data[:-6])
+
+
+def convertbits(data, frombits, tobits, pad=True):
+    """General power-of-2 base conversion."""
+    acc = 0
+    bits = 0
+    ret = []
+    maxv = (1 << tobits) - 1
+    max_acc = (1 << (frombits + tobits - 1)) - 1
+    for value in data:
+        if value < 0 or (value >> frombits):
+            return None
+        acc = ((acc << frombits) | value) & max_acc
+        bits += frombits
+        while bits >= tobits:
+            bits -= tobits
+            ret.append((acc >> bits) & maxv)
+    if pad:
+        if bits:
+            ret.append((acc << (tobits - bits)) & maxv)
+    elif bits >= frombits or ((acc << (tobits - bits)) & maxv):
+        return None
+    return ret
+
+
+def decode(hrp, addr):
+    """Decode a segwit address."""
+    hrpgot, data = bech32_decode(addr)
+    if hrpgot != hrp:
+        return (None, None)
+    decoded = convertbits(data[1:], 5, 8, False)
+    if decoded is None or len(decoded) < 2 or len(decoded) > 40:
+        return (None, None)
+    if data[0] > 16:
+        return (None, None)
+    if data[0] == 0 and len(decoded) != 20 and len(decoded) != 32:
+        return (None, None)
+    return (data[0], decoded)
+
+
+def encode(hrp, witver, witprog):
+    """Encode a segwit address."""
+    ret = bech32_encode(hrp, [witver] + convertbits(witprog, 8, 5))
+    if decode(hrp, ret) == (None, None):
+        return None
+    return ret
--- a/basicswap/contrib/test_framework/siphash.py
+++ b/basicswap/contrib/test_framework/siphash.py
@ -0,0 +1,63 @@
+#!/usr/bin/env python3
+# Copyright (c) 2016-2018 The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+"""Specialized SipHash-2-4 implementations.
+
+This implements SipHash-2-4 for 256-bit integers.
+"""
+
+def rotl64(n, b):
+    return n >> (64 - b) | (n & ((1 << (64 - b)) - 1)) << b
+
+def siphash_round(v0, v1, v2, v3):
+    v0 = (v0 + v1) & ((1 << 64) - 1)
+    v1 = rotl64(v1, 13)
+    v1 ^= v0
+    v0 = rotl64(v0, 32)
+    v2 = (v2 + v3) & ((1 << 64) - 1)
+    v3 = rotl64(v3, 16)
+    v3 ^= v2
+    v0 = (v0 + v3) & ((1 << 64) - 1)
+    v3 = rotl64(v3, 21)
+    v3 ^= v0
+    v2 = (v2 + v1) & ((1 << 64) - 1)
+    v1 = rotl64(v1, 17)
+    v1 ^= v2
+    v2 = rotl64(v2, 32)
+    return (v0, v1, v2, v3)
+
+def siphash256(k0, k1, h):
+    n0 = h & ((1 << 64) - 1)
+    n1 = (h >> 64) & ((1 << 64) - 1)
+    n2 = (h >> 128) & ((1 << 64) - 1)
+    n3 = (h >> 192) & ((1 << 64) - 1)
+    v0 = 0x736f6d6570736575 ^ k0
+    v1 = 0x646f72616e646f6d ^ k1
+    v2 = 0x6c7967656e657261 ^ k0
+    v3 = 0x7465646279746573 ^ k1 ^ n0
+    v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3)
+    v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3)
+    v0 ^= n0
+    v3 ^= n1
+    v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3)
+    v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3)
+    v0 ^= n1
+    v3 ^= n2
+    v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3)
+    v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3)
+    v0 ^= n2
+    v3 ^= n3
+    v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3)
+    v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3)
+    v0 ^= n3
+    v3 ^= 0x2000000000000000
+    v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3)
+    v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3)
+    v0 ^= 0x2000000000000000
+    v2 ^= 0xFF
+    v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3)
+    v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3)
+    v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3)
+    v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3)
+    return v0 ^ v1 ^ v2 ^ v3
--- a/basicswap/contrib/test_framework/util.py
+++ b/basicswap/contrib/test_framework/util.py
@ -0,0 +1,619 @@
+#!/usr/bin/env python3
+# Copyright (c) 2014-2020 The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+"""Helpful routines for regression testing."""
+
+from base64 import b64encode
+from binascii import unhexlify
+from decimal import Decimal, ROUND_DOWN
+from subprocess import CalledProcessError
+import inspect
+import json
+import logging
+import os
+import random
+import re
+import time
+
+from . import coverage
+from .authproxy import AuthServiceProxy, JSONRPCException
+from io import BytesIO
+
+logger = logging.getLogger("TestFramework.utils")
+
+# Assert functions
+##################
+
+
+def assert_approx(v, vexp, vspan=0.00001):
+    """Assert that `v` is within `vspan` of `vexp`"""
+    if v < vexp - vspan:
+        raise AssertionError("%s < [%s..%s]" % (str(v), str(vexp - vspan), str(vexp + vspan)))
+    if v > vexp + vspan:
+        raise AssertionError("%s > [%s..%s]" % (str(v), str(vexp - vspan), str(vexp + vspan)))
+
+
+def assert_fee_amount(fee, tx_size, fee_per_kB):
+    """Assert the fee was in range"""
+    target_fee = round(tx_size * fee_per_kB / 1000, 8)
+    if fee < target_fee:
+        raise AssertionError("Fee of %s BTC too low! (Should be %s BTC)" % (str(fee), str(target_fee)))
+    # allow the wallet's estimation to be at most 2 bytes off
+    if fee > (tx_size + 2) * fee_per_kB / 1000:
+        raise AssertionError("Fee of %s BTC too high! (Should be %s BTC)" % (str(fee), str(target_fee)))
+
+
+def assert_equal(thing1, thing2, *args):
+    if thing1 != thing2 or any(thing1 != arg for arg in args):
+        raise AssertionError("not(%s)" % " == ".join(str(arg) for arg in (thing1, thing2) + args))
+
+
+def assert_greater_than(thing1, thing2):
+    if thing1 <= thing2:
+        raise AssertionError("%s <= %s" % (str(thing1), str(thing2)))
+
+
+def assert_greater_than_or_equal(thing1, thing2):
+    if thing1 < thing2:
+        raise AssertionError("%s < %s" % (str(thing1), str(thing2)))
+
+
+def assert_raises(exc, fun, *args, **kwds):
+    assert_raises_message(exc, None, fun, *args, **kwds)
+
+
+def assert_raises_message(exc, message, fun, *args, **kwds):
+    try:
+        fun(*args, **kwds)
+    except JSONRPCException:
+        raise AssertionError("Use assert_raises_rpc_error() to test RPC failures")
+    except exc as e:
+        if message is not None and message not in e.error['message']:
+            raise AssertionError(
+                "Expected substring not found in error message:\nsubstring: '{}'\nerror message: '{}'.".format(
+                    message, e.error['message']))
+    except Exception as e:
+        raise AssertionError("Unexpected exception raised: " + type(e).__name__)
+    else:
+        raise AssertionError("No exception raised")
+
+
+def assert_raises_process_error(returncode, output, fun, *args, **kwds):
+    """Execute a process and asserts the process return code and output.
+
+    Calls function `fun` with arguments `args` and `kwds`. Catches a CalledProcessError
+    and verifies that the return code and output are as expected. Throws AssertionError if
+    no CalledProcessError was raised or if the return code and output are not as expected.
+
+    Args:
+        returncode (int): the process return code.
+        output (string): [a substring of] the process output.
+        fun (function): the function to call. This should execute a process.
+        args*: positional arguments for the function.
+        kwds**: named arguments for the function.
+    """
+    try:
+        fun(*args, **kwds)
+    except CalledProcessError as e:
+        if returncode != e.returncode:
+            raise AssertionError("Unexpected returncode %i" % e.returncode)
+        if output not in e.output:
+            raise AssertionError("Expected substring not found:" + e.output)
+    else:
+        raise AssertionError("No exception raised")
+
+
+def assert_raises_rpc_error(code, message, fun, *args, **kwds):
+    """Run an RPC and verify that a specific JSONRPC exception code and message is raised.
+
+    Calls function `fun` with arguments `args` and `kwds`. Catches a JSONRPCException
+    and verifies that the error code and message are as expected. Throws AssertionError if
+    no JSONRPCException was raised or if the error code/message are not as expected.
+
+    Args:
+        code (int), optional: the error code returned by the RPC call (defined
+            in src/rpc/protocol.h). Set to None if checking the error code is not required.
+        message (string), optional: [a substring of] the error string returned by the
+            RPC call. Set to None if checking the error string is not required.
+        fun (function): the function to call. This should be the name of an RPC.
+        args*: positional arguments for the function.
+        kwds**: named arguments for the function.
+    """
+    assert try_rpc(code, message, fun, *args, **kwds), "No exception raised"
+
+
+def try_rpc(code, message, fun, *args, **kwds):
+    """Tries to run an rpc command.
+
+    Test against error code and message if the rpc fails.
+    Returns whether a JSONRPCException was raised."""
+    try:
+        fun(*args, **kwds)
+    except JSONRPCException as e:
+        # JSONRPCException was thrown as expected. Check the code and message values are correct.
+        if (code is not None) and (code != e.error["code"]):
+            raise AssertionError("Unexpected JSONRPC error code %i" % e.error["code"])
+        if (message is not None) and (message not in e.error['message']):
+            raise AssertionError(
+                "Expected substring not found in error message:\nsubstring: '{}'\nerror message: '{}'.".format(
+                    message, e.error['message']))
+        return True
+    except Exception as e:
+        raise AssertionError("Unexpected exception raised: " + type(e).__name__)
+    else:
+        return False
+
+
+def assert_is_hex_string(string):
+    try:
+        int(string, 16)
+    except Exception as e:
+        raise AssertionError("Couldn't interpret %r as hexadecimal; raised: %s" % (string, e))
+
+
+def assert_is_hash_string(string, length=64):
+    if not isinstance(string, str):
+        raise AssertionError("Expected a string, got type %r" % type(string))
+    elif length and len(string) != length:
+        raise AssertionError("String of length %d expected; got %d" % (length, len(string)))
+    elif not re.match('[abcdef0-9]+$', string):
+        raise AssertionError("String %r contains invalid characters for a hash." % string)
+
+
+def assert_array_result(object_array, to_match, expected, should_not_find=False):
+    """
+        Pass in array of JSON objects, a dictionary with key/value pairs
+        to match against, and another dictionary with expected key/value
+        pairs.
+        If the should_not_find flag is true, to_match should not be found
+        in object_array
+        """
+    if should_not_find:
+        assert_equal(expected, {})
+    num_matched = 0
+    for item in object_array:
+        all_match = True
+        for key, value in to_match.items():
+            if item[key] != value:
+                all_match = False
+        if not all_match:
+            continue
+        elif should_not_find:
+            num_matched = num_matched + 1
+        for key, value in expected.items():
+            if item[key] != value:
+                raise AssertionError("%s : expected %s=%s" % (str(item), str(key), str(value)))
+            num_matched = num_matched + 1
+    if num_matched == 0 and not should_not_find:
+        raise AssertionError("No objects matched %s" % (str(to_match)))
+    if num_matched > 0 and should_not_find:
+        raise AssertionError("Objects were found %s" % (str(to_match)))
+
+
+# Utility functions
+###################
+
+
+def check_json_precision():
+    """Make sure json library being used does not lose precision converting BTC values"""
+    n = Decimal("20000000.00000003")
+    satoshis = int(json.loads(json.dumps(float(n))) * 1.0e8)
+    if satoshis != 2000000000000003:
+        raise RuntimeError("JSON encode/decode loses precision")
+
+
+def EncodeDecimal(o):
+    if isinstance(o, Decimal):
+        return str(o)
+    raise TypeError(repr(o) + " is not JSON serializable")
+
+
+def count_bytes(hex_string):
+    return len(bytearray.fromhex(hex_string))
+
+
+def hex_str_to_bytes(hex_str):
+    return unhexlify(hex_str.encode('ascii'))
+
+
+def str_to_b64str(string):
+    return b64encode(string.encode('utf-8')).decode('ascii')
+
+
+def satoshi_round(amount):
+    return Decimal(amount).quantize(Decimal('0.00000001'), rounding=ROUND_DOWN)
+
+
+def wait_until(predicate, *, attempts=float('inf'), timeout=float('inf'), lock=None, timeout_factor=1.0):
+    if attempts == float('inf') and timeout == float('inf'):
+        timeout = 60
+    timeout = timeout * timeout_factor
+    attempt = 0
+    time_end = time.time() + timeout
+
+    while attempt < attempts and time.time() < time_end:
+        if lock:
+            with lock:
+                if predicate():
+                    return
+        else:
+            if predicate():
+                return
+        attempt += 1
+        time.sleep(0.05)
+
+    # Print the cause of the timeout
+    predicate_source = "''''\n" + inspect.getsource(predicate) + "'''"
+    logger.error("wait_until() failed. Predicate: {}".format(predicate_source))
+    if attempt >= attempts:
+        raise AssertionError("Predicate {} not true after {} attempts".format(predicate_source, attempts))
+    elif time.time() >= time_end:
+        raise AssertionError("Predicate {} not true after {} seconds".format(predicate_source, timeout))
+    raise RuntimeError('Unreachable')
+
+
+# RPC/P2P connection constants and functions
+############################################
+
+# The maximum number of nodes a single test can spawn
+MAX_NODES = 12
+# Don't assign rpc or p2p ports lower than this
+PORT_MIN = int(os.getenv('TEST_RUNNER_PORT_MIN', default=11000))
+# The number of ports to "reserve" for p2p and rpc, each
+PORT_RANGE = 5000
+
+
+class PortSeed:
+    # Must be initialized with a unique integer for each process
+    n = None
+
+
+def get_rpc_proxy(url, node_number, *, timeout=None, coveragedir=None):
+    """
+    Args:
+        url (str): URL of the RPC server to call
+        node_number (int): the node number (or id) that this calls to
+
+    Kwargs:
+        timeout (int): HTTP timeout in seconds
+        coveragedir (str): Directory
+
+    Returns:
+        AuthServiceProxy. convenience object for making RPC calls.
+
+    """
+    proxy_kwargs = {}
+    if timeout is not None:
+        proxy_kwargs['timeout'] = int(timeout)
+
+    proxy = AuthServiceProxy(url, **proxy_kwargs)
+    proxy.url = url  # store URL on proxy for info
+
+    coverage_logfile = coverage.get_filename(coveragedir, node_number) if coveragedir else None
+
+    return coverage.AuthServiceProxyWrapper(proxy, coverage_logfile)
+
+
+def p2p_port(n):
+    assert n <= MAX_NODES
+    return PORT_MIN + n + (MAX_NODES * PortSeed.n) % (PORT_RANGE - 1 - MAX_NODES)
+
+
+def rpc_port(n):
+    return PORT_MIN + PORT_RANGE + n + (MAX_NODES * PortSeed.n) % (PORT_RANGE - 1 - MAX_NODES)
+
+
+def rpc_url(datadir, i, chain, rpchost):
+    rpc_u, rpc_p = get_auth_cookie(datadir, chain)
+    host = '127.0.0.1'
+    port = rpc_port(i)
+    if rpchost:
+        parts = rpchost.split(':')
+        if len(parts) == 2:
+            host, port = parts
+        else:
+            host = rpchost
+    return "http://%s:%s@%s:%d" % (rpc_u, rpc_p, host, int(port))
+
+
+# Node functions
+################
+
+
+def initialize_datadir(dirname, n, chain):
+    datadir = get_datadir_path(dirname, n)
+    if not os.path.isdir(datadir):
+        os.makedirs(datadir)
+    # Translate chain name to config name
+    if chain == 'testnet3':
+        chain_name_conf_arg = 'testnet'
+        chain_name_conf_section = 'test'
+    else:
+        chain_name_conf_arg = chain
+        chain_name_conf_section = chain
+    with open(os.path.join(datadir, "particl.conf"), 'w', encoding='utf8') as f:
+        f.write("{}=1\n".format(chain_name_conf_arg))
+        f.write("[{}]\n".format(chain_name_conf_section))
+        f.write("port=" + str(p2p_port(n)) + "\n")
+        f.write("rpcport=" + str(rpc_port(n)) + "\n")
+        f.write("fallbackfee=0.0002\n")
+        f.write("server=1\n")
+        f.write("keypool=1\n")
+        f.write("discover=0\n")
+        f.write("dnsseed=0\n")
+        f.write("listenonion=0\n")
+        f.write("printtoconsole=0\n")
+        f.write("upnp=0\n")
+        f.write("shrinkdebugfile=0\n")
+        os.makedirs(os.path.join(datadir, 'stderr'), exist_ok=True)
+        os.makedirs(os.path.join(datadir, 'stdout'), exist_ok=True)
+    return datadir
+
+
+def get_datadir_path(dirname, n):
+    return os.path.join(dirname, "node" + str(n))
+
+
+def append_config(datadir, options):
+    with open(os.path.join(datadir, "particl.conf"), 'a', encoding='utf8') as f:
+        for option in options:
+            f.write(option + "\n")
+
+
+def get_auth_cookie(datadir, chain):
+    user = None
+    password = None
+    if os.path.isfile(os.path.join(datadir, "particl.conf")):
+        with open(os.path.join(datadir, "particl.conf"), 'r', encoding='utf8') as f:
+            for line in f:
+                if line.startswith("rpcuser="):
+                    assert user is None  # Ensure that there is only one rpcuser line
+                    user = line.split("=")[1].strip("\n")
+                if line.startswith("rpcpassword="):
+                    assert password is None  # Ensure that there is only one rpcpassword line
+                    password = line.split("=")[1].strip("\n")
+    try:
+        with open(os.path.join(datadir, chain, ".cookie"), 'r', encoding="ascii") as f:
+            userpass = f.read()
+            split_userpass = userpass.split(':')
+            user = split_userpass[0]
+            password = split_userpass[1]
+    except OSError:
+        pass
+    if user is None or password is None:
+        raise ValueError("No RPC credentials")
+    return user, password
+
+
+# If a cookie file exists in the given datadir, delete it.
+def delete_cookie_file(datadir, chain):
+    if os.path.isfile(os.path.join(datadir, chain, ".cookie")):
+        logger.debug("Deleting leftover cookie file")
+        os.remove(os.path.join(datadir, chain, ".cookie"))
+
+
+def softfork_active(node, key):
+    """Return whether a softfork is active."""
+    return node.getblockchaininfo()['softforks'][key]['active']
+
+
+def set_node_times(nodes, t):
+    for node in nodes:
+        node.setmocktime(t)
+
+
+def disconnect_nodes(from_connection, node_num):
+    def get_peer_ids():
+        result = []
+        for peer in from_connection.getpeerinfo():
+            if "testnode{}".format(node_num) in peer['subver']:
+                result.append(peer['id'])
+        return result
+
+    peer_ids = get_peer_ids()
+    if not peer_ids:
+        logger.warning("disconnect_nodes: {} and {} were not connected".format(
+            from_connection.index,
+            node_num,
+        ))
+        return
+    for peer_id in peer_ids:
+        try:
+            from_connection.disconnectnode(nodeid=peer_id)
+        except JSONRPCException as e:
+            # If this node is disconnected between calculating the peer id
+            # and issuing the disconnect, don't worry about it.
+            # This avoids a race condition if we're mass-disconnecting peers.
+            if e.error['code'] != -29:  # RPC_CLIENT_NODE_NOT_CONNECTED
+                raise
+
+    # wait to disconnect
+    wait_until(lambda: not get_peer_ids(), timeout=5)
+
+
+def connect_nodes(from_connection, node_num):
+    ip_port = "127.0.0.1:" + str(p2p_port(node_num))
+    from_connection.addnode(ip_port, "onetry")
+    # poll until version handshake complete to avoid race conditions
+    # with transaction relaying
+    # See comments in net_processing:
+    # * Must have a version message before anything else
+    # * Must have a verack message before anything else
+    wait_until(lambda: all(peer['version'] != 0 for peer in from_connection.getpeerinfo()))
+    wait_until(lambda: all(peer['bytesrecv_per_msg'].pop('verack', 0) == 24 for peer in from_connection.getpeerinfo()))
+
+
+# Transaction/Block functions
+#############################
+
+
+def find_output(node, txid, amount, *, blockhash=None):
+    """
+    Return index to output of txid with value amount
+    Raises exception if there is none.
+    """
+    txdata = node.getrawtransaction(txid, 1, blockhash)
+    for i in range(len(txdata["vout"])):
+        if txdata["vout"][i]["value"] == amount:
+            return i
+    raise RuntimeError("find_output txid %s : %s not found" % (txid, str(amount)))
+
+
+def gather_inputs(from_node, amount_needed, confirmations_required=1):
+    """
+    Return a random set of unspent txouts that are enough to pay amount_needed
+    """
+    assert confirmations_required >= 0
+    utxo = from_node.listunspent(confirmations_required)
+    random.shuffle(utxo)
+    inputs = []
+    total_in = Decimal("0.00000000")
+    while total_in < amount_needed and len(utxo) > 0:
+        t = utxo.pop()
+        total_in += t["amount"]
+        inputs.append({"txid": t["txid"], "vout": t["vout"], "address": t["address"]})
+    if total_in < amount_needed:
+        raise RuntimeError("Insufficient funds: need %d, have %d" % (amount_needed, total_in))
+    return (total_in, inputs)
+
+
+def make_change(from_node, amount_in, amount_out, fee):
+    """
+    Create change output(s), return them
+    """
+    outputs = {}
+    amount = amount_out + fee
+    change = amount_in - amount
+    if change > amount * 2:
+        # Create an extra change output to break up big inputs
+        change_address = from_node.getnewaddress()
+        # Split change in two, being careful of rounding:
+        outputs[change_address] = Decimal(change / 2).quantize(Decimal('0.00000001'), rounding=ROUND_DOWN)
+        change = amount_in - amount - outputs[change_address]
+    if change > 0:
+        outputs[from_node.getnewaddress()] = change
+    return outputs
+
+
+def random_transaction(nodes, amount, min_fee, fee_increment, fee_variants):
+    """
+    Create a random transaction.
+    Returns (txid, hex-encoded-transaction-data, fee)
+    """
+    from_node = random.choice(nodes)
+    to_node = random.choice(nodes)
+    fee = min_fee + fee_increment * random.randint(0, fee_variants)
+
+    (total_in, inputs) = gather_inputs(from_node, amount + fee)
+    outputs = make_change(from_node, total_in, amount, fee)
+    outputs[to_node.getnewaddress()] = float(amount)
+
+    rawtx = from_node.createrawtransaction(inputs, outputs)
+    signresult = from_node.signrawtransactionwithwallet(rawtx)
+    txid = from_node.sendrawtransaction(signresult["hex"], 0)
+
+    return (txid, signresult["hex"], fee)
+
+
+# Helper to create at least "count" utxos
+# Pass in a fee that is sufficient for relay and mining new transactions.
+def create_confirmed_utxos(fee, node, count):
+    to_generate = int(0.5 * count) + 101
+    while to_generate > 0:
+        node.generate(min(25, to_generate))
+        to_generate -= 25
+    utxos = node.listunspent()
+    iterations = count - len(utxos)
+    addr1 = node.getnewaddress()
+    addr2 = node.getnewaddress()
+    if iterations <= 0:
+        return utxos
+    for i in range(iterations):
+        t = utxos.pop()
+        inputs = []
+        inputs.append({"txid": t["txid"], "vout": t["vout"]})
+        outputs = {}
+        send_value = t['amount'] - fee
+        outputs[addr1] = satoshi_round(send_value / 2)
+        outputs[addr2] = satoshi_round(send_value / 2)
+        raw_tx = node.createrawtransaction(inputs, outputs)
+        signed_tx = node.signrawtransactionwithwallet(raw_tx)["hex"]
+        node.sendrawtransaction(signed_tx)
+
+    while (node.getmempoolinfo()['size'] > 0):
+        node.generate(1)
+
+    utxos = node.listunspent()
+    assert len(utxos) >= count
+    return utxos
+
+
+# Create large OP_RETURN txouts that can be appended to a transaction
+# to make it large (helper for constructing large transactions).
+def gen_return_txouts():
+    # Some pre-processing to create a bunch of OP_RETURN txouts to insert into transactions we create
+    # So we have big transactions (and therefore can't fit very many into each block)
+    # create one script_pubkey
+    script_pubkey = "6a4d0200"  # OP_RETURN OP_PUSH2 512 bytes
+    for i in range(512):
+        script_pubkey = script_pubkey + "01"
+    # concatenate 128 txouts of above script_pubkey which we'll insert before the txout for change
+    txouts = []
+    from .messages import CTxOut
+    txout = CTxOut()
+    txout.nValue = 0
+    txout.scriptPubKey = hex_str_to_bytes(script_pubkey)
+    for k in range(128):
+        txouts.append(txout)
+    return txouts
+
+
+# Create a spend of each passed-in utxo, splicing in "txouts" to each raw
+# transaction to make it large.  See gen_return_txouts() above.
+def create_lots_of_big_transactions(node, txouts, utxos, num, fee):
+    addr = node.getnewaddress()
+    txids = []
+    from .messages import CTransaction
+    for _ in range(num):
+        t = utxos.pop()
+        inputs = [{"txid": t["txid"], "vout": t["vout"]}]
+        outputs = {}
+        change = t['amount'] - fee
+        outputs[addr] = satoshi_round(change)
+        rawtx = node.createrawtransaction(inputs, outputs)
+        tx = CTransaction()
+        tx.deserialize(BytesIO(hex_str_to_bytes(rawtx)))
+        for txout in txouts:
+            tx.vout.append(txout)
+        newtx = tx.serialize().hex()
+        signresult = node.signrawtransactionwithwallet(newtx, None, "NONE")
+        txid = node.sendrawtransaction(signresult["hex"], 0)
+        txids.append(txid)
+    return txids
+
+
+def mine_large_block(node, utxos=None):
+    # generate a 66k transaction,
+    # and 14 of them is close to the 1MB block limit
+    num = 14
+    txouts = gen_return_txouts()
+    utxos = utxos if utxos is not None else []
+    if len(utxos) < num:
+        utxos.clear()
+        utxos.extend(node.listunspent())
+    fee = 100 * node.getnetworkinfo()["relayfee"]
+    create_lots_of_big_transactions(node, txouts, utxos, num, fee=fee)
+    node.generate(1)
+
+
+def find_vout_for_address(node, txid, addr):
+    """
+    Locate the vout index of the given transaction sending to the
+    given address. Raises runtime error exception if not found.
+    """
+    tx = node.getrawtransaction(txid, True)
+    for i in range(len(tx["vout"])):
+        if any([addr == a for a in tx["vout"][i]["scriptPubKey"]["addresses"]]):
+            return i
+    raise RuntimeError("Vout not found for address: txid=%s, addr=%s" % (txid, addr))
--- a/basicswap/contrib/test_framework/wallet_util.py
+++ b/basicswap/contrib/test_framework/wallet_util.py
@ -0,0 +1,131 @@
+#!/usr/bin/env python3
+# Copyright (c) 2018-2020 The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+"""Useful util functions for testing the wallet"""
+from collections import namedtuple
+
+from .address import (
+    byte_to_base58,
+    key_to_p2pkh,
+    key_to_p2sh_p2wpkh,
+    key_to_p2wpkh,
+    script_to_p2sh,
+    script_to_p2sh_p2wsh,
+    script_to_p2wsh,
+)
+from .key import ECKey
+from .script import (
+    CScript,
+    OP_0,
+    OP_2,
+    OP_3,
+    OP_CHECKMULTISIG,
+    OP_CHECKSIG,
+    OP_DUP,
+    OP_EQUAL,
+    OP_EQUALVERIFY,
+    OP_HASH160,
+    hash160,
+    sha256,
+)
+from .util import hex_str_to_bytes
+
+Key = namedtuple('Key', ['privkey',
+                         'pubkey',
+                         'p2pkh_script',
+                         'p2pkh_addr',
+                         'p2wpkh_script',
+                         'p2wpkh_addr',
+                         'p2sh_p2wpkh_script',
+                         'p2sh_p2wpkh_redeem_script',
+                         'p2sh_p2wpkh_addr'])
+
+Multisig = namedtuple('Multisig', ['privkeys',
+                                   'pubkeys',
+                                   'p2sh_script',
+                                   'p2sh_addr',
+                                   'redeem_script',
+                                   'p2wsh_script',
+                                   'p2wsh_addr',
+                                   'p2sh_p2wsh_script',
+                                   'p2sh_p2wsh_addr'])
+
+def get_key(node):
+    """Generate a fresh key on node
+
+    Returns a named tuple of privkey, pubkey and all address and scripts."""
+    addr = node.getnewaddress()
+    pubkey = node.getaddressinfo(addr)['pubkey']
+    pkh = hash160(hex_str_to_bytes(pubkey))
+    return Key(privkey=node.dumpprivkey(addr),
+               pubkey=pubkey,
+               p2pkh_script=CScript([OP_DUP, OP_HASH160, pkh, OP_EQUALVERIFY, OP_CHECKSIG]).hex(),
+               p2pkh_addr=key_to_p2pkh(pubkey),
+               p2wpkh_script=CScript([OP_0, pkh]).hex(),
+               p2wpkh_addr=key_to_p2wpkh(pubkey),
+               p2sh_p2wpkh_script=CScript([OP_HASH160, hash160(CScript([OP_0, pkh])), OP_EQUAL]).hex(),
+               p2sh_p2wpkh_redeem_script=CScript([OP_0, pkh]).hex(),
+               p2sh_p2wpkh_addr=key_to_p2sh_p2wpkh(pubkey))
+
+def get_generate_key():
+    """Generate a fresh key
+
+    Returns a named tuple of privkey, pubkey and all address and scripts."""
+    eckey = ECKey()
+    eckey.generate()
+    privkey = bytes_to_wif(eckey.get_bytes())
+    pubkey = eckey.get_pubkey().get_bytes().hex()
+    pkh = hash160(hex_str_to_bytes(pubkey))
+    return Key(privkey=privkey,
+               pubkey=pubkey,
+               p2pkh_script=CScript([OP_DUP, OP_HASH160, pkh, OP_EQUALVERIFY, OP_CHECKSIG]).hex(),
+               p2pkh_addr=key_to_p2pkh(pubkey),
+               p2wpkh_script=CScript([OP_0, pkh]).hex(),
+               p2wpkh_addr=key_to_p2wpkh(pubkey),
+               p2sh_p2wpkh_script=CScript([OP_HASH160, hash160(CScript([OP_0, pkh])), OP_EQUAL]).hex(),
+               p2sh_p2wpkh_redeem_script=CScript([OP_0, pkh]).hex(),
+               p2sh_p2wpkh_addr=key_to_p2sh_p2wpkh(pubkey))
+
+def get_multisig(node):
+    """Generate a fresh 2-of-3 multisig on node
+
+    Returns a named tuple of privkeys, pubkeys and all address and scripts."""
+    addrs = []
+    pubkeys = []
+    for _ in range(3):
+        addr = node.getaddressinfo(node.getnewaddress())
+        addrs.append(addr['address'])
+        pubkeys.append(addr['pubkey'])
+    script_code = CScript([OP_2] + [hex_str_to_bytes(pubkey) for pubkey in pubkeys] + [OP_3, OP_CHECKMULTISIG])
+    witness_script = CScript([OP_0, sha256(script_code)])
+    return Multisig(privkeys=[node.dumpprivkey(addr) for addr in addrs],
+                    pubkeys=pubkeys,
+                    p2sh_script=CScript([OP_HASH160, hash160(script_code), OP_EQUAL]).hex(),
+                    p2sh_addr=script_to_p2sh(script_code),
+                    redeem_script=script_code.hex(),
+                    p2wsh_script=witness_script.hex(),
+                    p2wsh_addr=script_to_p2wsh(script_code),
+                    p2sh_p2wsh_script=CScript([OP_HASH160, witness_script, OP_EQUAL]).hex(),
+                    p2sh_p2wsh_addr=script_to_p2sh_p2wsh(script_code))
+
+def test_address(node, address, **kwargs):
+    """Get address info for `address` and test whether the returned values are as expected."""
+    addr_info = node.getaddressinfo(address)
+    for key, value in kwargs.items():
+        if value is None:
+            if key in addr_info.keys():
+                raise AssertionError("key {} unexpectedly returned in getaddressinfo.".format(key))
+        elif addr_info[key] != value:
+            raise AssertionError("key {} value {} did not match expected value {}".format(key, addr_info[key], value))
+
+def bytes_to_wif(b, compressed=True, prefix=239):
+    if compressed:
+        b += b'\x01'
+    return byte_to_base58(b, prefix)
+
+def generate_wif_key():
+    # Makes a WIF privkey for imports
+    k = ECKey()
+    k.generate()
+    return bytes_to_wif(k.get_bytes(), k.is_compressed)
--- a/basicswap/db.py
+++ b/basicswap/db.py
@ -97,7 +97,7 @@ class Bid(Base):
    participate_txn_refund = sa.Column(sa.LargeBinary)

    state = sa.Column(sa.Integer)
-    state_time = sa.Column(sa.BigInteger)  # timestamp of last state change
+    state_time = sa.Column(sa.BigInteger)  # Timestamp of last state change
    states = sa.Column(sa.LargeBinary)  # Packed states and times

    state_note = sa.Column(sa.String)
--- a/basicswap/ecc_util.py
+++ b/basicswap/ecc_util.py
@ -0,0 +1,222 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+import os
+import codecs
+import hashlib
+import secrets
+
+from .contrib.ellipticcurve import CurveFp, Point, INFINITY, jacobi_symbol
+
+
+class ECCParameters():
+    def __init__(self, p, a, b, Gx, Gy, o):
+        self.p = p
+        self.a = a
+        self.b = b
+        self.Gx = Gx
+        self.Gy = Gy
+        self.o = o
+
+
+ep = ECCParameters( \
+    p  = 0xfffffffffffffffffffffffffffffffffffffffffffffffffffffffefffffc2f, \
+    a  = 0x0, \
+    b  = 0x7, \
+    Gx = 0x79be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798, \
+    Gy = 0x483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8, \
+    o  = 0xfffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141)  # noqa: E221,E251,E502
+
+curve_secp256k1 = CurveFp(ep.p, ep.a, ep.b)
+G = Point(curve_secp256k1, ep.Gx, ep.Gy, ep.o)
+SECP256K1_ORDER_HALF = ep.o // 2
+
+
+def ToDER(P):
+    return bytes((4, )) + int(P.x()).to_bytes(32, byteorder='big') + int(P.y()).to_bytes(32, byteorder='big')
+
+
+def bytes32ToInt(b):
+    return int.from_bytes(b, byteorder='big')
+
+
+def intToBytes32(i):
+    return i.to_bytes(32, byteorder='big')
+
+
+def intToBytes32_le(i):
+    return i.to_bytes(32, byteorder='little')
+
+
+def bytesToHexStr(b):
+    return codecs.encode(b, 'hex').decode('utf-8')
+
+
+def hexStrToBytes(h):
+    if h.startswith('0x'):
+        h = h[2:]
+    return bytes.fromhex(h)
+
+
+def getSecretBytes():
+    i = 1 + secrets.randbelow(ep.o - 1)
+    return intToBytes32(i)
+
+
+def getSecretInt():
+    return 1 + secrets.randbelow(ep.o - 1)
+
+
+def getInsecureBytes():
+    while True:
+        s = os.urandom(32)
+
+        s_test = int.from_bytes(s, byteorder='big')
+        if s_test > 1 and s_test < ep.o:
+            return s
+
+
+def getInsecureInt():
+    while True:
+        s = os.urandom(32)
+
+        s_test = int.from_bytes(s, byteorder='big')
+        if s_test > 1 and s_test < ep.o:
+            return s_test
+
+
+def powMod(x, y, z):
+    # Calculate (x ** y) % z efficiently.
+    number = 1
+    while y:
+        if y & 1:
+            number = number * x % z
+        y >>= 1  # y //= 2
+
+        x = x * x % z
+    return number
+
+
+def ExpandPoint(xb, sign):
+    x = int.from_bytes(xb, byteorder='big')
+    a = (powMod(x, 3, ep.p) + 7) % ep.p
+    y = powMod(a, (ep.p + 1) // 4, ep.p)
+
+    if sign:
+        y = ep.p - y
+    return Point(curve_secp256k1, x, y, ep.o)
+
+
+def CPKToPoint(cpk):
+    y_parity = cpk[0] - 2
+
+    x = int.from_bytes(cpk[1:], byteorder='big')
+    a = (powMod(x, 3, ep.p) + 7) % ep.p
+    y = powMod(a, (ep.p + 1) // 4, ep.p)
+
+    if y % 2 != y_parity:
+        y = ep.p - y
+
+    return Point(curve_secp256k1, x, y, ep.o)
+
+
+def pointToCPK2(point, ind=0x09):
+    # The function is_square(x), where x is an integer, returns whether or not x is a quadratic residue modulo p. Since p is prime, it is equivalent to the Legendre symbol (x / p) = x(p-1)/2 mod p being equal to 1[8].
+    ind = bytes((ind ^ (1 if jacobi_symbol(point.y(), ep.p) == 1 else 0),))
+    return ind + point.x().to_bytes(32, byteorder='big')
+
+
+def pointToCPK(point):
+
+    y = point.y().to_bytes(32, byteorder='big')
+    ind = bytes((0x03,)) if y[31] % 2 else bytes((0x02,))
+
+    cpk = ind + point.x().to_bytes(32, byteorder='big')
+    return cpk
+
+
+def secretToCPK(secret):
+    secretInt = secret if isinstance(secret, int) \
+        else int.from_bytes(secret, byteorder='big')
+
+    R = G * secretInt
+
+    Y = R.y().to_bytes(32, byteorder='big')
+    ind = bytes((0x03,)) if Y[31] % 2 else bytes((0x02,))
+
+    pubkey = ind + R.x().to_bytes(32, byteorder='big')
+
+    return pubkey
+
+
+def getKeypair():
+    secretBytes = getSecretBytes()
+    return secretBytes, secretToCPK(secretBytes)
+
+
+def hashToCurve(pubkey):
+
+    xBytes = hashlib.sha256(pubkey).digest()
+    x = int.from_bytes(xBytes, byteorder='big')
+
+    for k in range(0, 100):
+        # get matching y element for point
+        y_parity = 0  # always pick 0,
+        a = (powMod(x, 3, ep.p) + 7) % ep.p
+        y = powMod(a, (ep.p + 1) // 4, ep.p)
+
+        # print("before parity %x" % (y))
+        if y % 2 != y_parity:
+            y = ep.p - y
+
+        # If x is always mod P, can R ever not be on the curve?
+        try:
+            R = Point(curve_secp256k1, x, y, ep.o)
+        except Exception:
+            x = (x + 1) % ep.p  # % P?
+            continue
+
+        if R == INFINITY or R * ep.o != INFINITY:  # is R * O != INFINITY check necessary?  Validation of Elliptic Curve Public Keys says no if cofactor = 1
+            x = (x + 1) % ep.p  # % P?
+            continue
+        return R
+
+    raise ValueError('hashToCurve failed for 100 tries')
+
+
+def hash256(inb):
+    return hashlib.sha256(inb).digest()
+
+
+i2b = intToBytes32
+b2i = bytes32ToInt
+b2h = bytesToHexStr
+h2b = hexStrToBytes
+
+
+def i2h(x):
+    return b2h(i2b(x))
+
+
+def testEccUtils():
+    print('testEccUtils()')
+
+    G_enc = ToDER(G)
+    assert(G_enc.hex() == '0479be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8')
+
+    G_enc = pointToCPK(G)
+    assert(G_enc.hex() == '0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798')
+    G_dec = CPKToPoint(G_enc)
+    assert(G_dec == G)
+
+    G_enc = pointToCPK2(G)
+    assert(G_enc.hex() == '0879be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798')
+
+    H = hashToCurve(ToDER(G))
+    assert(pointToCPK(H).hex() == '0250929b74c1a04954b78b4b6035e97a5e078a5a0f28ec96d547bfee9ace803ac0')
+
+    print('Passed.')
+
+
+if __name__ == "__main__":
+    testEccUtils()
--- a/basicswap/http_server.py
+++ b/basicswap/http_server.py
@ -19,7 +19,7 @@ from . import __version__
 from .util import (
    COIN,
    format8,
-    makeInt,
+    make_int,
    dumpj,
 )
 from .chainparams import (
@ -129,7 +129,7 @@ def validateAmountString(amount):

 def inputAmount(amount_str):
    validateAmountString(amount_str)
-    return makeInt(amount_str)
+    return make_int(amount_str)


 def setCoinFilter(form_data, field_name):
--- a/basicswap/interface_btc.py
+++ b/basicswap/interface_btc.py
@ -0,0 +1,805 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright (c) 2020 tecnovert
+# Distributed under the MIT software license, see the accompanying
+# file LICENSE or http://www.opensource.org/licenses/mit-license.php.
+
+import time
+import hashlib
+import logging
+from io import BytesIO
+
+from .util import (
+    decodeScriptNum,
+    getCompactSizeLen,
+    dumpj,
+    format_amount,
+    make_int
+)
+
+from .ecc_util import (
+    G, ep,
+    pointToCPK, CPKToPoint,
+    getSecretInt,
+    b2h, i2b, b2i, i2h)
+
+from .contrib.test_framework.messages import (
+    COIN,
+    COutPoint,
+    CTransaction,
+    CTxIn,
+    CTxInWitness,
+    CTxOut,
+    FromHex,
+    ToHex)
+
+from .contrib.test_framework.script import (
+    CScript,
+    CScriptOp,
+    CScriptNum,
+    OP_IF, OP_ELSE, OP_ENDIF,
+    OP_0,
+    OP_2,
+    OP_16,
+    OP_EQUALVERIFY,
+    OP_CHECKSIG,
+    OP_SIZE,
+    OP_SHA256,
+    OP_CHECKMULTISIG,
+    OP_CHECKSEQUENCEVERIFY,
+    OP_DROP,
+    SIGHASH_ALL,
+    SegwitV0SignatureHash,
+    hash160)
+
+from .contrib.test_framework.key import ECKey, ECPubKey
+
+from .chainparams import CoinInterface
+from .rpc import make_rpc_func
+from .util import assert_cond
+
+
+def findOutput(tx, script_pk):
+    for i in range(len(tx.vout)):
+        if tx.vout[i].scriptPubKey == script_pk:
+            return i
+    return None
+
+
+class BTCInterface(CoinInterface):
+    @staticmethod
+    def exp():
+        return 8
+
+    @staticmethod
+    def nbk():
+        return 32
+
+    @staticmethod
+    def nbK():  # No. of bytes requires to encode a public key
+        return 33
+
+    @staticmethod
+    def witnessScaleFactor():
+        return 4
+
+    @staticmethod
+    def txVersion():
+        return 2
+
+    @staticmethod
+    def getTxOutputValue(tx):
+        rv = 0
+        for output in tx.vout:
+            rv += output.nValue
+        return rv
+
+    def compareFeeRates(self, a, b):
+        return abs(a - b) < 20
+
+    def __init__(self, coin_settings):
+        self.rpc_callback = make_rpc_func(coin_settings['rpcport'], coin_settings['rpcauth'])
+        self.txoType = CTxOut
+
+    def getNewSecretKey(self):
+        return getSecretInt()
+
+    def pubkey(self, key):
+        return G * key
+
+    def encodePubkey(self, pk):
+        return pointToCPK(pk)
+
+    def decodePubkey(self, pke):
+        return CPKToPoint(pke)
+
+    def decodeKey(self, k):
+        i = b2i(k)
+        assert(i < ep.o)
+        return i
+
+    def sumKeys(self, ka, kb):
+        return (ka + kb) % ep.o
+
+    def sumPubkeys(self, Ka, Kb):
+        return Ka + Kb
+
+    def extractScriptLockScriptValues(self, script_bytes):
+        script_len = len(script_bytes)
+        assert_cond(script_len > 112, 'Bad script length')
+        assert_cond(script_bytes[0] == OP_IF)
+        assert_cond(script_bytes[1] == OP_SIZE)
+        assert_cond(script_bytes[2:4] == bytes((1, 32)))  # 0120, CScriptNum length, then data
+        assert_cond(script_bytes[4] == OP_EQUALVERIFY)
+        assert_cond(script_bytes[5] == OP_SHA256)
+        assert_cond(script_bytes[6] == 32)
+        secret_hash = script_bytes[7: 7 + 32]
+        assert_cond(script_bytes[39] == OP_EQUALVERIFY)
+        assert_cond(script_bytes[40] == OP_2)
+        assert_cond(script_bytes[41] == 33)
+        pk1 = script_bytes[42: 42 + 33]
+        assert_cond(script_bytes[75] == 33)
+        pk2 = script_bytes[76: 76 + 33]
+        assert_cond(script_bytes[109] == OP_2)
+        assert_cond(script_bytes[110] == OP_CHECKMULTISIG)
+        assert_cond(script_bytes[111] == OP_ELSE)
+        o = 112
+
+        #  Decode script num
+        csv_val, nb = decodeScriptNum(script_bytes, o)
+        o += nb
+
+        assert_cond(script_len == o + 8 + 66, 'Bad script length')  # Fails if script too long
+        assert_cond(script_bytes[o] == OP_CHECKSEQUENCEVERIFY)
+        o += 1
+        assert_cond(script_bytes[o] == OP_DROP)
+        o += 1
+        assert_cond(script_bytes[o] == OP_2)
+        o += 1
+        assert_cond(script_bytes[o] == 33)
+        o += 1
+        pk3 = script_bytes[o: o + 33]
+        o += 33
+        assert_cond(script_bytes[o] == 33)
+        o += 1
+        pk4 = script_bytes[o: o + 33]
+        o += 33
+        assert_cond(script_bytes[o] == OP_2)
+        o += 1
+        assert_cond(script_bytes[o] == OP_CHECKMULTISIG)
+        o += 1
+        assert_cond(script_bytes[o] == OP_ENDIF)
+
+        return secret_hash, pk1, pk2, csv_val, pk3, pk4
+
+    def genScriptLockTxScript(self, sh, Kal, Kaf, lock_blocks, Karl, Karf):
+        return CScript([
+            CScriptOp(OP_IF),
+            CScriptOp(OP_SIZE), 32, CScriptOp(OP_EQUALVERIFY),
+            CScriptOp(OP_SHA256), sh, CScriptOp(OP_EQUALVERIFY),
+            2, self.encodePubkey(Kal), self.encodePubkey(Kaf), 2, CScriptOp(OP_CHECKMULTISIG),
+            CScriptOp(OP_ELSE),
+            lock_blocks, CScriptOp(OP_CHECKSEQUENCEVERIFY), CScriptOp(OP_DROP),
+            2, self.encodePubkey(Karl), self.encodePubkey(Karf), 2, CScriptOp(OP_CHECKMULTISIG),
+            CScriptOp(OP_ENDIF)])
+
+    def createScriptLockTx(self, value, sh, Kal, Kaf, lock_blocks, Karl, Karf):
+
+        script = self.genScriptLockTxScript(sh, Kal, Kaf, lock_blocks, Karl, Karf)
+        tx = CTransaction()
+        tx.nVersion = self.txVersion()
+        tx.vout.append(self.txoType(value, CScript([OP_0, hashlib.sha256(script).digest()])))
+
+        return tx, script
+
+    def extractScriptLockRefundScriptValues(self, script_bytes):
+        script_len = len(script_bytes)
+        assert_cond(script_len > 73, 'Bad script length')
+        assert_cond(script_bytes[0] == OP_IF)
+        assert_cond(script_bytes[1] == OP_2)
+        assert_cond(script_bytes[2] == 33)
+        pk1 = script_bytes[3: 3 + 33]
+        assert_cond(script_bytes[36] == 33)
+        pk2 = script_bytes[37: 37 + 33]
+        assert_cond(script_bytes[70] == OP_2)
+        assert_cond(script_bytes[71] == OP_CHECKMULTISIG)
+        assert_cond(script_bytes[72] == OP_ELSE)
+        o = 73
+        csv_val, nb = decodeScriptNum(script_bytes, o)
+        o += nb
+
+        assert_cond(script_len == o + 5 + 33, 'Bad script length')  # Fails if script too long
+        assert_cond(script_bytes[o] == OP_CHECKSEQUENCEVERIFY)
+        o += 1
+        assert_cond(script_bytes[o] == OP_DROP)
+        o += 1
+        assert_cond(script_bytes[o] == 33)
+        o += 1
+        pk3 = script_bytes[o: o + 33]
+        o += 33
+        assert_cond(script_bytes[o] == OP_CHECKSIG)
+        o += 1
+        assert_cond(script_bytes[o] == OP_ENDIF)
+
+        return pk1, pk2, csv_val, pk3
+
+    def genScriptLockRefundTxScript(self, Karl, Karf, csv_val, Kaf):
+        return CScript([
+            CScriptOp(OP_IF),
+            2, self.encodePubkey(Karl), self.encodePubkey(Karf), 2, CScriptOp(OP_CHECKMULTISIG),
+            CScriptOp(OP_ELSE),
+            csv_val, CScriptOp(OP_CHECKSEQUENCEVERIFY), CScriptOp(OP_DROP),
+            self.encodePubkey(Kaf), CScriptOp(OP_CHECKSIG),
+            CScriptOp(OP_ENDIF)])
+
+    def createScriptLockRefundTx(self, tx_lock, script_lock, Karl, Karf, csv_val, Kaf, tx_fee_rate):
+
+        output_script = CScript([OP_0, hashlib.sha256(script_lock).digest()])
+        locked_n = findOutput(tx_lock, output_script)
+        assert_cond(locked_n is not None, 'Output not found in tx')
+        locked_coin = tx_lock.vout[locked_n].nValue
+
+        tx_lock.rehash()
+        tx_lock_hash_int = tx_lock.sha256
+
+        sh, A, B, lock1_value, C, D = self.extractScriptLockScriptValues(script_lock)
+
+        refund_script = self.genScriptLockRefundTxScript(Karl, Karf, csv_val, Kaf)
+        tx = CTransaction()
+        tx.nVersion = self.txVersion()
+        tx.vin.append(CTxIn(COutPoint(tx_lock_hash_int, locked_n), nSequence=lock1_value))
+        tx.vout.append(self.txoType(locked_coin, CScript([OP_0, hashlib.sha256(refund_script).digest()])))
+
+        witness_bytes = len(script_lock)
+        witness_bytes += 73 * 2  # 2 signatures (72 + 1 byts size)
+        witness_bytes += 2  # 2 empty witness stack values
+        witness_bytes += getCompactSizeLen(witness_bytes)
+        vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes)
+        pay_fee = int(tx_fee_rate * vsize / 1000)
+        tx.vout[0].nValue = locked_coin - pay_fee
+
+        tx.rehash()
+        logging.info('createScriptLockRefundTx %s:\n    fee_rate, vsize, fee: %ld, %ld, %ld.',
+                     i2h(tx.sha256), tx_fee_rate, vsize, pay_fee)
+
+        return tx, refund_script, tx.vout[0].nValue
+
+    def createScriptLockRefundSpendTx(self, tx_lock_refund, script_lock_refund, Kal, tx_fee_rate):
+        # Returns the coinA locked coin to the leader
+        # The follower will sign the multisig path with a signature encumbered by the leader's coinB spend pubkey
+        # When the leader publishes the decrypted signature the leader's coinB spend privatekey will be revealed to the follower
+
+        output_script = CScript([OP_0, hashlib.sha256(script_lock_refund).digest()])
+        locked_n = findOutput(tx_lock_refund, output_script)
+        assert_cond(locked_n is not None, 'Output not found in tx')
+        locked_coin = tx_lock_refund.vout[locked_n].nValue
+
+        tx_lock_refund.rehash()
+        tx_lock_refund_hash_int = tx_lock_refund.sha256
+
+        tx = CTransaction()
+        tx.nVersion = self.txVersion()
+        tx.vin.append(CTxIn(COutPoint(tx_lock_refund_hash_int, locked_n), nSequence=0))
+
+        pubkeyhash = hash160(self.encodePubkey(Kal))
+        tx.vout.append(self.txoType(locked_coin, CScript([OP_0, pubkeyhash])))
+
+        witness_bytes = len(script_lock_refund)
+        witness_bytes += 73 * 2  # 2 signatures (72 + 1 byte size)
+        witness_bytes += 4  # 1 empty, 1 true witness stack values
+        witness_bytes += getCompactSizeLen(witness_bytes)
+        vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes)
+        pay_fee = int(tx_fee_rate * vsize / 1000)
+        tx.vout[0].nValue = locked_coin - pay_fee
+
+        tx.rehash()
+        logging.info('createScriptLockRefundSpendTx %s:\n    fee_rate, vsize, fee: %ld, %ld, %ld.',
+                     i2h(tx.sha256), tx_fee_rate, vsize, pay_fee)
+
+        return tx
+
+    def createScriptLockRefundSpendToFTx(self, tx_lock_refund, script_lock_refund, pkh_dest, tx_fee_rate):
+        # Sends the coinA locked coin to the follower
+        output_script = CScript([OP_0, hashlib.sha256(script_lock_refund).digest()])
+        locked_n = findOutput(tx_lock_refund, output_script)
+        assert_cond(locked_n is not None, 'Output not found in tx')
+        locked_coin = tx_lock_refund.vout[locked_n].nValue
+
+        A, B, lock2_value, C = self.extractScriptLockRefundScriptValues(script_lock_refund)
+
+        tx_lock_refund.rehash()
+        tx_lock_refund_hash_int = tx_lock_refund.sha256
+
+        tx = CTransaction()
+        tx.nVersion = self.txVersion()
+        tx.vin.append(CTxIn(COutPoint(tx_lock_refund_hash_int, locked_n), nSequence=lock2_value))
+
+        tx.vout.append(self.txoType(locked_coin, CScript([OP_0, pkh_dest])))
+
+        witness_bytes = len(script_lock_refund)
+        witness_bytes += 73  # signature (72 + 1 byte size)
+        witness_bytes += 1  # 1 empty stack value
+        witness_bytes += getCompactSizeLen(witness_bytes)
+        vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes)
+        pay_fee = int(tx_fee_rate * vsize / 1000)
+        tx.vout[0].nValue = locked_coin - pay_fee
+
+        tx.rehash()
+        logging.info('createScriptLockRefundSpendToFTx %s:\n    fee_rate, vsize, fee: %ld, %ld, %ld.',
+                     i2h(tx.sha256), tx_fee_rate, vsize, pay_fee)
+
+        return tx
+
+    def createScriptLockSpendTx(self, tx_lock, script_lock, pkh_dest, tx_fee_rate):
+
+        output_script = CScript([OP_0, hashlib.sha256(script_lock).digest()])
+        locked_n = findOutput(tx_lock, output_script)
+        assert_cond(locked_n is not None, 'Output not found in tx')
+        locked_coin = tx_lock.vout[locked_n].nValue
+
+        tx_lock.rehash()
+        tx_lock_hash_int = tx_lock.sha256
+
+        tx = CTransaction()
+        tx.nVersion = self.txVersion()
+        tx.vin.append(CTxIn(COutPoint(tx_lock_hash_int, locked_n)))
+
+        p2wpkh = CScript([OP_0, pkh_dest])
+        tx.vout.append(self.txoType(locked_coin, p2wpkh))
+
+        witness_bytes = len(script_lock)
+        witness_bytes += 33  # sv, size
+        witness_bytes += 73 * 2  # 2 signatures (72 + 1 byts size)
+        witness_bytes += 4  # 1 empty, 1 true witness stack values
+        witness_bytes += getCompactSizeLen(witness_bytes)
+        vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes)
+        pay_fee = int(tx_fee_rate * vsize / 1000)
+        tx.vout[0].nValue = locked_coin - pay_fee
+
+        tx.rehash()
+        logging.info('createScriptLockSpendTx %s:\n    fee_rate, vsize, fee: %ld, %ld, %ld.',
+                     i2h(tx.sha256), tx_fee_rate, vsize, pay_fee)
+
+        return tx
+
+    def verifyLockTx(self, tx, script_out,
+                     swap_value,
+                     sh,
+                     Kal, Kaf,
+                     lock_value, feerate,
+                     Karl, Karf,
+                     check_lock_tx_inputs):
+        # Verify:
+        #
+
+        # Not necessary to check the lock txn is mineable, as protocol will wait for it to confirm
+        # However by checking early we can avoid wasting time processing unmineable txns
+        # Check fee is reasonable
+
+        tx_hash = self.getTxHash(tx)
+        logging.info('Verifying lock tx: {}.'.format(b2h(tx_hash)))
+
+        assert_cond(tx.nVersion == self.txVersion(), 'Bad version')
+        assert_cond(tx.nLockTime == 0, 'Bad nLockTime')
+
+        script_pk = CScript([OP_0, hashlib.sha256(script_out).digest()])
+        locked_n = findOutput(tx, script_pk)
+        assert_cond(locked_n is not None, 'Output not found in tx')
+        locked_coin = tx.vout[locked_n].nValue
+
+        assert_cond(locked_coin == swap_value, 'Bad locked value')
+
+        # Check script and values
+        shv, A, B, csv_val, C, D = self.extractScriptLockScriptValues(script_out)
+        assert_cond(shv == sh, 'Bad hash lock')
+        assert_cond(A == self.encodePubkey(Kal), 'Bad script pubkey')
+        assert_cond(B == self.encodePubkey(Kaf), 'Bad script pubkey')
+        assert_cond(csv_val == lock_value, 'Bad script csv value')
+        assert_cond(C == self.encodePubkey(Karl), 'Bad script pubkey')
+        assert_cond(D == self.encodePubkey(Karf), 'Bad script pubkey')
+
+        if check_lock_tx_inputs:
+            # Check that inputs are unspent and verify fee rate
+            inputs_value = 0
+            add_bytes = 0
+            add_witness_bytes = getCompactSizeLen(len(tx.vin))
+            for pi in tx.vin:
+                ptx = self.rpc_callback('getrawtransaction', [i2h(pi.prevout.hash), True])
+                print('ptx', dumpj(ptx))
+                prevout = ptx['vout'][pi.prevout.n]
+                inputs_value += make_int(prevout['value'])
+
+                prevout_type = prevout['scriptPubKey']['type']
+                if prevout_type == 'witness_v0_keyhash':
+                    add_witness_bytes += 107  # sig 72, pk 33 and 2 size bytes
+                    add_witness_bytes += getCompactSizeLen(107)
+                else:
+                    # Assume P2PKH, TODO more types
+                    add_bytes += 107  # OP_PUSH72 <ecdsa_signature> OP_PUSH33 <public_key>
+
+            outputs_value = 0
+            for txo in tx.vout:
+                outputs_value += txo.nValue
+            fee_paid = inputs_value - outputs_value
+            assert(fee_paid > 0)
+
+            vsize = self.getTxVSize(tx, add_bytes, add_witness_bytes)
+            fee_rate_paid = fee_paid * 1000 / vsize
+
+            logging.info('tx amount, vsize, feerate: %ld, %ld, %ld', locked_coin, vsize, fee_rate_paid)
+
+            if not self.compareFeeRates(fee_rate_paid, feerate):
+                logging.warning('feerate paid doesn\'t match expected: %ld, %ld', fee_rate_paid, feerate)
+                # TODO: Display warning to user
+
+        return tx_hash, locked_n
+
+    def verifyLockRefundTx(self, tx, script_out,
+                           prevout_id, prevout_n, prevout_seq, prevout_script,
+                           Karl, Karf, csv_val_expect, Kaf, swap_value, feerate):
+        # Verify:
+        #   Must have only one input with correct prevout and sequence
+        #   Must have only one output to the p2wsh of the lock refund script
+        #   Output value must be locked_coin - lock tx fee
+
+        tx_hash = self.getTxHash(tx)
+        logging.info('Verifying lock refund tx: {}.'.format(b2h(tx_hash)))
+
+        assert_cond(tx.nVersion == self.txVersion(), 'Bad version')
+        assert_cond(tx.nLockTime == 0, 'nLockTime not 0')
+        assert_cond(len(tx.vin) == 1, 'tx doesn\'t have one input')
+
+        assert_cond(tx.vin[0].nSequence == prevout_seq, 'Bad input nSequence')
+        assert_cond(len(tx.vin[0].scriptSig) == 0, 'Input scriptsig not empty')
+        assert_cond(tx.vin[0].prevout.hash == b2i(prevout_id) and tx.vin[0].prevout.n == prevout_n, 'Input prevout mismatch')
+
+        assert_cond(len(tx.vout) == 1, 'tx doesn\'t have one output')
+
+        script_pk = CScript([OP_0, hashlib.sha256(script_out).digest()])
+        locked_n = findOutput(tx, script_pk)
+        assert_cond(locked_n is not None, 'Output not found in tx')
+        locked_coin = tx.vout[locked_n].nValue
+
+        # Check script and values
+        A, B, csv_val, C = self.extractScriptLockRefundScriptValues(script_out)
+        assert_cond(A == self.encodePubkey(Karl), 'Bad script pubkey')
+        assert_cond(B == self.encodePubkey(Karf), 'Bad script pubkey')
+        assert_cond(csv_val == csv_val_expect, 'Bad script csv value')
+        assert_cond(C == self.encodePubkey(Kaf), 'Bad script pubkey')
+
+        fee_paid = swap_value - locked_coin
+        assert(fee_paid > 0)
+
+        witness_bytes = len(prevout_script)
+        witness_bytes += 73 * 2  # 2 signatures (72 + 1 byts size)
+        witness_bytes += 2  # 2 empty witness stack values
+        witness_bytes += getCompactSizeLen(witness_bytes)
+        vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes)
+        fee_rate_paid = fee_paid * 1000 / vsize
+
+        logging.info('tx amount, vsize, feerate: %ld, %ld, %ld', locked_coin, vsize, fee_rate_paid)
+
+        if not self.compareFeeRates(fee_rate_paid, feerate):
+            raise ValueError('Bad fee rate')
+
+        return tx_hash, locked_coin
+
+    def verifyLockRefundSpendTx(self, tx,
+                                lock_refund_tx_id, prevout_script,
+                                Kal,
+                                prevout_value, feerate):
+        # Verify:
+        #   Must have only one input with correct prevout (n is always 0) and sequence
+        #   Must have only one output sending lock refund tx value - fee to leader's address, TODO: follower shouldn't need to verify destination addr
+        tx_hash = self.getTxHash(tx)
+        logging.info('Verifying lock refund spend tx: {}.'.format(b2h(tx_hash)))
+
+        assert_cond(tx.nVersion == self.txVersion(), 'Bad version')
+        assert_cond(tx.nLockTime == 0, 'nLockTime not 0')
+        assert_cond(len(tx.vin) == 1, 'tx doesn\'t have one input')
+
+        assert_cond(tx.vin[0].nSequence == 0, 'Bad input nSequence')
+        assert_cond(len(tx.vin[0].scriptSig) == 0, 'Input scriptsig not empty')
+        assert_cond(tx.vin[0].prevout.hash == b2i(lock_refund_tx_id) and tx.vin[0].prevout.n == 0, 'Input prevout mismatch')
+
+        assert_cond(len(tx.vout) == 1, 'tx doesn\'t have one output')
+
+        p2wpkh = CScript([OP_0, hash160(self.encodePubkey(Kal))])
+        locked_n = findOutput(tx, p2wpkh)
+        assert_cond(locked_n is not None, 'Output not found in lock refund spend tx')
+        tx_value = tx.vout[locked_n].nValue
+
+        fee_paid = prevout_value - tx_value
+        assert(fee_paid > 0)
+
+        witness_bytes = len(prevout_script)
+        witness_bytes += 73 * 2  # 2 signatures (72 + 1 byts size)
+        witness_bytes += 4  # 1 empty, 1 true witness stack values
+        witness_bytes += getCompactSizeLen(witness_bytes)
+        vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes)
+        fee_rate_paid = fee_paid * 1000 / vsize
+
+        logging.info('tx amount, vsize, feerate: %ld, %ld, %ld', tx_value, vsize, fee_rate_paid)
+
+        if not self.compareFeeRates(fee_rate_paid, feerate):
+            raise ValueError('Bad fee rate')
+
+        return True
+
+    def verifyLockSpendTx(self, tx,
+                          lock_tx, lock_tx_script,
+                          a_pkhash_f, feerate):
+        # Verify:
+        #   Must have only one input with correct prevout (n is always 0) and sequence
+        #   Must have only one output with destination and amount
+
+        tx_hash = self.getTxHash(tx)
+        logging.info('Verifying lock spend tx: {}.'.format(b2h(tx_hash)))
+
+        assert_cond(tx.nVersion == self.txVersion(), 'Bad version')
+        assert_cond(tx.nLockTime == 0, 'nLockTime not 0')
+        assert_cond(len(tx.vin) == 1, 'tx doesn\'t have one input')
+
+        lock_tx_id = self.getTxHash(lock_tx)
+
+        output_script = CScript([OP_0, hashlib.sha256(lock_tx_script).digest()])
+        locked_n = findOutput(lock_tx, output_script)
+        assert_cond(locked_n is not None, 'Output not found in tx')
+        locked_coin = lock_tx.vout[locked_n].nValue
+
+        assert_cond(tx.vin[0].nSequence == 0, 'Bad input nSequence')
+        assert_cond(len(tx.vin[0].scriptSig) == 0, 'Input scriptsig not empty')
+        assert_cond(tx.vin[0].prevout.hash == b2i(lock_tx_id) and tx.vin[0].prevout.n == locked_n, 'Input prevout mismatch')
+
+        assert_cond(len(tx.vout) == 1, 'tx doesn\'t have one output')
+        p2wpkh = CScript([OP_0, a_pkhash_f])
+        assert_cond(tx.vout[0].scriptPubKey == p2wpkh, 'Bad output destination')
+
+        fee_paid = locked_coin - tx.vout[0].nValue
+        assert(fee_paid > 0)
+
+        witness_bytes = len(lock_tx_script)
+        witness_bytes += 33  # sv, size
+        witness_bytes += 73 * 2  # 2 signatures (72 + 1 byts size)
+        witness_bytes += 4  # 1 empty, 1 true witness stack values
+        witness_bytes += getCompactSizeLen(witness_bytes)
+        vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes)
+        fee_rate_paid = fee_paid * 1000 / vsize
+
+        logging.info('tx amount, vsize, feerate: %ld, %ld, %ld', tx.vout[0].nValue, vsize, fee_rate_paid)
+
+        if not self.compareFeeRates(fee_rate_paid, feerate):
+            raise ValueError('Bad fee rate')
+
+        return True
+
+    def signTx(self, key_int, tx, prevout_n, prevout_script, prevout_value):
+        sig_hash = SegwitV0SignatureHash(prevout_script, tx, prevout_n, SIGHASH_ALL, prevout_value)
+
+        eck = ECKey()
+        eck.set(i2b(key_int), compressed=True)
+
+        return eck.sign_ecdsa(sig_hash) + b'\x01'  # 0x1 is SIGHASH_ALL
+
+    def signTxOtVES(self, key_sign, key_encrypt, tx, prevout_n, prevout_script, prevout_value):
+        sig_hash = SegwitV0SignatureHash(prevout_script, tx, prevout_n, SIGHASH_ALL, prevout_value)
+        return otves.EncSign(key_sign, key_encrypt, sig_hash)
+
+    def verifyTxOtVES(self, tx, sig, Ks, Ke, prevout_n, prevout_script, prevout_value):
+        sig_hash = SegwitV0SignatureHash(prevout_script, tx, prevout_n, SIGHASH_ALL, prevout_value)
+        return otves.EncVrfy(Ks, Ke, sig_hash, sig)
+
+    def decryptOtVES(self, k, esig):
+        return otves.DecSig(k, esig) + b'\x01'  # 0x1 is SIGHASH_ALL
+
+    def verifyTxSig(self, tx, sig, K, prevout_n, prevout_script, prevout_value):
+        sig_hash = SegwitV0SignatureHash(prevout_script, tx, prevout_n, SIGHASH_ALL, prevout_value)
+
+        ecK = ECPubKey()
+        ecK.set_int(K.x(), K.y())
+        return ecK.verify_ecdsa(sig[: -1], sig_hash)  # Pop the hashtype byte
+
+    def fundTx(self, tx, feerate):
+        feerate_str = format_amount(feerate, self.exp())
+        rv = self.rpc_callback('fundrawtransaction', [ToHex(tx), {'feeRate': feerate_str}])
+        return FromHex(tx, rv['hex'])
+
+    def signTxWithWallet(self, tx):
+        rv = self.rpc_callback('signrawtransactionwithwallet', [ToHex(tx)])
+
+        return FromHex(tx, rv['hex'])
+
+    def publishTx(self, tx):
+        return self.rpc_callback('sendrawtransaction', [ToHex(tx)])
+
+    def encodeTx(self, tx):
+        return tx.serialize()
+
+    def loadTx(self, tx_bytes):
+        # Load tx from bytes to internal representation
+        tx = CTransaction()
+        tx.deserialize(BytesIO(tx_bytes))
+        return tx
+
+    def getTxHash(self, tx):
+        tx.rehash()
+        return i2b(tx.sha256)
+
+    def getPubkeyHash(self, K):
+        return hash160(self.encodePubkey(K))
+
+    def getScriptDest(self, script):
+        return CScript([OP_0, hashlib.sha256(script).digest()])
+
+    def getPkDest(self, K):
+        return CScript([OP_0, self.getPubkeyHash(K)])
+
+    def scanTxOutset(self, dest):
+        return self.rpc_callback('scantxoutset', ['start', ['raw({})'.format(dest.hex())]])
+
+    def getTransaction(self, txid):
+        try:
+            return self.rpc_callback('getrawtransaction', [txid.hex()])
+        except Exception as ex:
+            # TODO: filter errors
+            return None
+
+    def setTxSignature(self, tx, stack):
+        tx.wit.vtxinwit.clear()
+        tx.wit.vtxinwit.append(CTxInWitness())
+        tx.wit.vtxinwit[0].scriptWitness.stack = stack
+        return True
+
+    def extractLeaderSig(self, tx):
+        return tx.wit.vtxinwit[0].scriptWitness.stack[1]
+
+    def extractFollowerSig(self, tx):
+        return tx.wit.vtxinwit[0].scriptWitness.stack[2]
+
+    def createBLockTx(self, Kbs, output_amount):
+        tx = CTransaction()
+        tx.nVersion = self.txVersion()
+        p2wpkh = self.getPkDest(Kbs)
+        tx.vout.append(self.txoType(output_amount, p2wpkh))
+        return tx
+
+    def publishBLockTx(self, Kbv, Kbs, output_amount, feerate):
+        b_lock_tx = self.createBLockTx(Kbs, output_amount)
+
+        b_lock_tx = self.fundTx(b_lock_tx, feerate)
+        b_lock_tx_id = self.getTxHash(b_lock_tx)
+        b_lock_tx = self.signTxWithWallet(b_lock_tx)
+
+        return self.publishTx(b_lock_tx)
+
+    def recoverEncKey(self, esig, sig, K):
+        return otves.RecoverEncKey(esig, sig[:-1], K)  # Strip sighash type
+
+    def getTxVSize(self, tx, add_bytes=0, add_witness_bytes=0):
+        wsf = self.witnessScaleFactor()
+        len_full = len(tx.serialize_with_witness()) + add_bytes + add_witness_bytes
+        len_nwit = len(tx.serialize_without_witness()) + add_bytes
+        weight = len_nwit * (wsf - 1) + len_full
+        return (weight + wsf - 1) // wsf
+
+    def findTxB(self, kbv, Kbs, cb_swap_value, cb_block_confirmed, restore_height):
+        raw_dest = self.getPkDest(Kbs)
+
+        rv = self.scanTxOutset(raw_dest)
+        print('scanTxOutset', dumpj(rv))
+
+        for utxo in rv['unspents']:
+            if 'height' in utxo and utxo['height'] > 0 and rv['height'] - utxo['height'] > cb_block_confirmed:
+                if utxo['amount'] * COIN != cb_swap_value:
+                    logging.warning('Found output to lock tx pubkey of incorrect value: %s', str(utxo['amount']))
+                else:
+                    return True
+        return False
+
+    def waitForLockTxB(self, kbv, Kbs, cb_swap_value, cb_block_confirmed):
+
+        raw_dest = self.getPkDest(Kbs)
+
+        for i in range(20):
+            time.sleep(1)
+            rv = self.scanTxOutset(raw_dest)
+            print('scanTxOutset', dumpj(rv))
+
+            for utxo in rv['unspents']:
+                if 'height' in utxo and utxo['height'] > 0 and rv['height'] - utxo['height'] > cb_block_confirmed:
+
+                    if utxo['amount'] * COIN != cb_swap_value:
+                        logging.warning('Found output to lock tx pubkey of incorrect value: %s', str(utxo['amount']))
+                    else:
+                        return True
+        return False
+
+    def spendBLockTx(self, address_to, kbv, kbs, cb_swap_value, b_fee, restore_height):
+        print('TODO: spendBLockTx')
+
+
+def testBTCInterface():
+    print('testBTCInterface')
+    script_bytes = bytes.fromhex('6382012088a820aaf125ff9a34a74c7a17f5e7ee9d07d17cc5e53a539f345d5f73baa7e79b65e28852210224019219ad43c47288c937ae508f26998dd81ec066827773db128fd5e262c04f21039a0fd752bd1a2234820707852e7a30253620052ecd162948a06532a817710b5952ae670114b2755221038689deba25c5578e5457ddadbaf8aeb8badf438dc22f540503dbd4ae10e14f512103c9c5d5acc996216d10852a72cd67c701bfd4b9137a4076350fd32f08db39575552ae68')
+    i = BTCInterface(None)
+    sh, a, b, csv_val, c, d = i.extractScriptLockScriptValues(script_bytes)
+    assert(csv_val == 20)
+
+    script_bytes_t = script_bytes + bytes((0x00,))
+    try:
+        sh, a, b, csv_val, c, d = i.extractScriptLockScriptValues(script_bytes_t)
+        assert(False), 'Should fail'
+    except Exception as e:
+        assert(str(e) == 'Bad script length')
+
+    script_bytes_t = script_bytes[:-1]
+    try:
+        sh, a, b, csv_val, c, d = i.extractScriptLockScriptValues(script_bytes_t)
+        assert(False), 'Should fail'
+    except Exception as e:
+        assert(str(e) == 'Bad script length')
+
+    script_bytes_t = bytes((0x00,)) + script_bytes[1:]
+    try:
+        sh, a, b, csv_val, c, d = i.extractScriptLockScriptValues(script_bytes_t)
+        assert(False), 'Should fail'
+    except Exception as e:
+        assert(str(e) == 'Bad opcode')
+
+    # Remove the csv value
+    script_part_a = script_bytes[:112]
+    script_part_b = script_bytes[114:]
+
+    script_bytes_t = script_part_a + bytes((0x00,)) + script_part_b
+    sh, a, b, csv_val, c, d = i.extractScriptLockScriptValues(script_bytes_t)
+    assert(csv_val == 0)
+
+    script_bytes_t = script_part_a + bytes((OP_16,)) + script_part_b
+    sh, a, b, csv_val, c, d = i.extractScriptLockScriptValues(script_bytes_t)
+    assert(csv_val == 16)
+
+    script_bytes_t = script_part_a + CScriptNum.encode(CScriptNum(17)) + script_part_b
+    sh, a, b, csv_val, c, d = i.extractScriptLockScriptValues(script_bytes_t)
+    assert(csv_val == 17)
+
+    script_bytes_t = script_part_a + CScriptNum.encode(CScriptNum(-15)) + script_part_b
+    sh, a, b, csv_val, c, d = i.extractScriptLockScriptValues(script_bytes_t)
+    assert(csv_val == -15)
+
+    script_bytes_t = script_part_a + CScriptNum.encode(CScriptNum(4000)) + script_part_b
+    sh, a, b, csv_val, c, d = i.extractScriptLockScriptValues(script_bytes_t)
+    assert(csv_val == 4000)
+
+    max_pos = 0x7FFFFFFF
+    script_bytes_t = script_part_a + CScriptNum.encode(CScriptNum(max_pos)) + script_part_b
+    sh, a, b, csv_val, c, d = i.extractScriptLockScriptValues(script_bytes_t)
+    assert(csv_val == max_pos)
+    script_bytes_t = script_part_a + CScriptNum.encode(CScriptNum(max_pos - 1)) + script_part_b
+    sh, a, b, csv_val, c, d = i.extractScriptLockScriptValues(script_bytes_t)
+    assert(csv_val == max_pos - 1)
+
+    script_bytes_t = script_part_a + CScriptNum.encode(CScriptNum(max_pos + 1)) + script_part_b
+    try:
+        sh, a, b, csv_val, c, d = i.extractScriptLockScriptValues(script_bytes_t)
+        assert(False), 'Should fail'
+    except Exception as e:
+        assert(str(e) == 'Bad scriptnum length')
+
+    min_neg = -2147483647
+    script_bytes_t = script_part_a + CScriptNum.encode(CScriptNum(min_neg)) + script_part_b
+    sh, a, b, csv_val, c, d = i.extractScriptLockScriptValues(script_bytes_t)
+    assert(csv_val == min_neg)
+
+    script_bytes_t = script_part_a + CScriptNum.encode(CScriptNum(min_neg - 1)) + script_part_b
+    try:
+        sh, a, b, csv_val, c, d = i.extractScriptLockScriptValues(script_bytes_t)
+        assert(False), 'Should fail'
+    except Exception as e:
+        assert(str(e) == 'Bad scriptnum length')
+
+    print('Passed.')
+
+
+if __name__ == "__main__":
+    testBTCInterface()
--- a/basicswap/interface_ltc.py
+++ b/basicswap/interface_ltc.py
@ -0,0 +1,12 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright (c) 2020 tecnovert
+# Distributed under the MIT software license, see the accompanying
+# file LICENSE or http://www.opensource.org/licenses/mit-license.php.
+
+from .interface_btc import BTCInterface
+
+
+class LTCInterface(BTCInterface):
+    pass
--- a/basicswap/interface_part.py
+++ b/basicswap/interface_part.py
@ -0,0 +1,28 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright (c) 2020 tecnovert
+# Distributed under the MIT software license, see the accompanying
+# file LICENSE or http://www.opensource.org/licenses/mit-license.php.
+
+from .contrib.test_framework.messages import (
+    CTxOutPart,
+)
+
+from .interface_btc import BTCInterface
+from .chainparams import CoinInterface
+from .rpc import make_rpc_func
+
+
+class PARTInterface(BTCInterface):
+    @staticmethod
+    def witnessScaleFactor():
+        return 2
+
+    @staticmethod
+    def txVersion():
+        return 0xa0
+
+    def __init__(self, coin_settings):
+        self.rpc_callback = make_rpc_func(coin_settings['rpcport'], coin_settings['rpcauth'])
+        self.txoType = CTxOutPart
--- a/basicswap/interface_xmr.py
+++ b/basicswap/interface_xmr.py
@ -0,0 +1,230 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright (c) 2020 tecnovert
+# Distributed under the MIT software license, see the accompanying
+# file LICENSE or http://www.opensource.org/licenses/mit-license.php.
+
+import time
+import logging
+
+from .chainparams import CoinInterface
+from .rpc_xmr import make_xmr_rpc_func, make_xmr_wallet_rpc_func
+
+XMR_COIN = 10 ** 12
+
+
+class XMRInterface(CoinInterface):
+    @staticmethod
+    def exp():
+        return 12
+
+    @staticmethod
+    def nbk():
+        return 32
+
+    @staticmethod
+    def nbK():  # No. of bytes requires to encode a public key
+        return 32
+
+    def __init__(self, coin_settings):
+        rpc_cb = make_xmr_rpc_func(coin_settings['rpcport'])
+        rpc_wallet_cb = make_xmr_wallet_rpc_func(coin_settings['walletrpcport'], coin_settings['walletrpcauth'])
+
+        self.rpc_cb = rpc_cb  # Not essential
+        self.rpc_wallet_cb = rpc_wallet_cb
+
+    def getNewSecretKey(self):
+        return edu.get_secret()
+
+    def pubkey(self, key):
+        return edf.scalarmult_B(key)
+
+    def encodePubkey(self, pk):
+        return edu.encodepoint(pk)
+
+    def decodePubkey(self, pke):
+        return edf.decodepoint(pke)
+
+    def decodeKey(self, k):
+        i = b2i(k)
+        assert(i < edf.l and i > 8)
+        return i
+
+    def sumKeys(self, ka, kb):
+        return (ka + kb) % edf.l
+
+    def sumPubkeys(self, Ka, Kb):
+        return edf.edwards_add(Ka, Kb)
+
+    def publishBLockTx(self, Kbv, Kbs, output_amount, feerate):
+
+        shared_addr = xmr_util.encode_address(self.encodePubkey(Kbv), self.encodePubkey(Kbs))
+
+        # TODO: How to set feerate?
+        params = {'destinations': [{'amount': output_amount, 'address': shared_addr}]}
+        rv = self.rpc_wallet_cb('transfer', params)
+        logging.info('publishBLockTx %s to address_b58 %s', rv['tx_hash'], shared_addr)
+
+        return rv['tx_hash']
+
+    def findTxB(self, kbv, Kbs, cb_swap_value, cb_block_confirmed, restore_height):
+        Kbv_enc = self.encodePubkey(self.pubkey(kbv))
+        address_b58 = xmr_util.encode_address(Kbv_enc, self.encodePubkey(Kbs))
+
+        try:
+            self.rpc_wallet_cb('close_wallet')
+        except Exception as e:
+            logging.warning('close_wallet failed %s', str(e))
+
+        params = {
+            'restore_height': restore_height,
+            'filename': address_b58,
+            'address': address_b58,
+            'viewkey': b2h(intToBytes32_le(kbv)),
+        }
+
+        try:
+            rv = self.rpc_wallet_cb('open_wallet', {'filename': address_b58})
+        except Exception as e:
+            rv = self.rpc_wallet_cb('generate_from_keys', params)
+            logging.info('generate_from_keys %s', dumpj(rv))
+            rv = self.rpc_wallet_cb('open_wallet', {'filename': address_b58})
+
+        # Debug
+        try:
+            current_height = self.rpc_cb('get_block_count')['count']
+            logging.info('findTxB XMR current_height %d\nAddress: %s', current_height, address_b58)
+        except Exception as e:
+            logging.info('rpc_cb failed %s', str(e))
+            current_height = None  # If the transfer is available it will be deep enough
+
+        # For a while after opening the wallet rpc cmds return empty data
+        for i in range(5):
+            params = {'transfer_type': 'available'}
+            rv = self.rpc_wallet_cb('incoming_transfers', params)
+            if 'transfers' in rv:
+                for transfer in rv['transfers']:
+                    if transfer['amount'] == cb_swap_value \
+                       and (current_height is None or current_height - transfer['block_height'] > cb_block_confirmed):
+                        return True
+            time.sleep(1 + i)
+
+        return False
+
+    def waitForLockTxB(self, kbv, Kbs, cb_swap_value, cb_block_confirmed, restore_height):
+
+        Kbv_enc = self.encodePubkey(self.pubkey(kbv))
+        address_b58 = xmr_util.encode_address(Kbv_enc, self.encodePubkey(Kbs))
+
+        try:
+            self.rpc_wallet_cb('close_wallet')
+        except Exception as e:
+            logging.warning('close_wallet failed %s', str(e))
+
+        params = {
+            'filename': address_b58,
+            'address': address_b58,
+            'viewkey': b2h(intToBytes32_le(kbv)),
+            'restore_height': restore_height,
+        }
+        self.rpc_wallet_cb('generate_from_keys', params)
+
+        self.rpc_wallet_cb('open_wallet', {'filename': address_b58})
+        # For a while after opening the wallet rpc cmds return empty data
+
+        num_tries = 40
+        for i in range(num_tries + 1):
+            try:
+                current_height = self.rpc_cb('get_block_count')['count']
+                print('current_height', current_height)
+            except Exception as e:
+                logging.warning('rpc_cb failed %s', str(e))
+                current_height = None  # If the transfer is available it will be deep enough
+
+            # TODO: Make accepting current_height == None a user selectable option
+            #       Or look for all transfers and check height
+
+            params = {'transfer_type': 'available'}
+            rv = self.rpc_wallet_cb('incoming_transfers', params)
+            print('rv', rv)
+
+            if 'transfers' in rv:
+                for transfer in rv['transfers']:
+                    if transfer['amount'] == cb_swap_value \
+                       and (current_height is None or current_height - transfer['block_height'] > cb_block_confirmed):
+                        return True
+
+            # TODO: Is it necessary to check the address?
+
+            '''
+            rv = self.rpc_wallet_cb('get_balance')
+            print('get_balance', rv)
+
+            if 'per_subaddress' in rv:
+                for sub_addr in rv['per_subaddress']:
+                    if sub_addr['address'] == address_b58:
+
+            '''
+
+            if i >= num_tries:
+                raise ValueError('Balance not confirming on node')
+            time.sleep(1)
+
+        return False
+
+    def spendBLockTx(self, address_to, kbv, kbs, cb_swap_value, b_fee_rate, restore_height):
+
+        Kbv_enc = self.encodePubkey(self.pubkey(kbv))
+        Kbs_enc = self.encodePubkey(self.pubkey(kbs))
+        address_b58 = xmr_util.encode_address(Kbv_enc, Kbs_enc)
+
+        try:
+            self.rpc_wallet_cb('close_wallet')
+        except Exception as e:
+            logging.warning('close_wallet failed %s', str(e))
+
+        wallet_filename = address_b58 + '_spend'
+
+        params = {
+            'filename': wallet_filename,
+            'address': address_b58,
+            'viewkey': b2h(intToBytes32_le(kbv)),
+            'spendkey': b2h(intToBytes32_le(kbs)),
+            'restore_height': restore_height,
+        }
+
+        try:
+            self.rpc_wallet_cb('open_wallet', {'filename': wallet_filename})
+        except Exception as e:
+            rv = self.rpc_wallet_cb('generate_from_keys', params)
+            logging.info('generate_from_keys %s', dumpj(rv))
+            self.rpc_wallet_cb('open_wallet', {'filename': wallet_filename})
+
+        # For a while after opening the wallet rpc cmds return empty data
+        for i in range(10):
+            rv = self.rpc_wallet_cb('get_balance')
+            print('get_balance', rv)
+            if rv['balance'] >= cb_swap_value:
+                break
+
+            time.sleep(1 + i)
+
+        # TODO: need a subfee from output option
+        b_fee = b_fee_rate * 10  # Guess
+
+        num_tries = 20
+        for i in range(1 + num_tries):
+            try:
+                params = {'destinations': [{'amount': cb_swap_value - b_fee, 'address': address_to}]}
+                rv = self.rpc_wallet_cb('transfer', params)
+                print('transfer', rv)
+                break
+            except Exception as e:
+                print('str(e)', str(e))
+            if i >= num_tries:
+                raise ValueError('transfer failed.')
+            b_fee += b_fee_rate
+            logging.info('Raising fee to %d', b_fee)
+
+        return rv['tx_hash']
--- a/basicswap/rpc.py
+++ b/basicswap/rpc.py
@ -93,8 +93,8 @@ class Jsonrpc():
 def callrpc(rpc_port, auth, method, params=[], wallet=None):
    try:
        url = 'http://%s@127.0.0.1:%d/' % (auth, rpc_port)
-        if wallet:
-            url += 'wallet/' + wallet
+        if wallet is not None:
+            url += 'wallet/' + urllib.parse.quote(wallet)
        x = Jsonrpc(url)

        v = x.json_request(method, params)
@ -126,3 +126,14 @@ def callrpc_cli(bindir, datadir, chain, cmd, cli_bin='particl-cli'):
    except Exception:
        pass
    return r
+
+
+def make_rpc_func(port, auth, wallet=None):
+    port = port
+    auth = auth
+    wallet = wallet
+
+    def rpc_func(method, params=None, wallet_override=None):
+        nonlocal port, auth, wallet
+        return callrpc(port, auth, method, params, wallet if wallet_override is None else wallet_override)
+    return rpc_func
--- a/basicswap/rpc_xmr.py
+++ b/basicswap/rpc_xmr.py
@ -0,0 +1,85 @@
+# -*- coding: utf-8 -*-
+
+import json
+import requests
+
+
+def callrpc_xmr(rpc_port, auth, method, params=[], path='json_rpc'):
+    # auth is a tuple: (username, password)
+    try:
+        url = 'http://127.0.0.1:{}/{}'.format(rpc_port, path)
+        request_body = {
+            'method': method,
+            'params': params,
+            'id': 2,
+            'jsonrpc': '2.0'
+        }
+        headers = {
+            'content-type': 'application/json'
+        }
+        p = requests.post(url, data=json.dumps(request_body), auth=requests.auth.HTTPDigestAuth(auth[0], auth[1]), headers=headers)
+        r = json.loads(p.text)
+    except Exception as ex:
+        raise ValueError('RPC Server Error: {}'.format(str(ex)))
+
+    if 'error' in r and r['error'] is not None:
+        raise ValueError('RPC error ' + str(r['error']))
+
+    return r['result']
+
+
+def callrpc_xmr_na(rpc_port, method, params=[], path='json_rpc'):
+    try:
+        url = 'http://127.0.0.1:{}/{}'.format(rpc_port, path)
+        request_body = {
+            'method': method,
+            'params': params,
+            'id': 2,
+            'jsonrpc': '2.0'
+        }
+        headers = {
+            'content-type': 'application/json'
+        }
+        p = requests.post(url, data=json.dumps(request_body), headers=headers)
+        r = json.loads(p.text)
+    except Exception as ex:
+        raise ValueError('RPC Server Error: {}'.format(str(ex)))
+
+    if 'error' in r and r['error'] is not None:
+        raise ValueError('RPC error ' + str(r['error']))
+
+    return r['result']
+
+
+def callrpc_xmr2(rpc_port, method, params=[]):
+    try:
+        url = 'http://127.0.0.1:{}/{}'.format(rpc_port, method)
+        headers = {
+            'content-type': 'application/json'
+        }
+        p = requests.post(url, data=json.dumps(params), headers=headers)
+        r = json.loads(p.text)
+    except Exception as ex:
+        raise ValueError('RPC Server Error: {}'.format(str(ex)))
+
+    return r
+
+
+def make_xmr_rpc_func(port):
+    port = port
+
+    def rpc_func(method, params=None, wallet=None):
+        nonlocal port
+        return callrpc_xmr_na(port, method, params)
+    return rpc_func
+
+
+def make_xmr_wallet_rpc_func(port, auth):
+    port = port
+    auth = auth
+
+    def rpc_func(method, params=None, wallet=None):
+        nonlocal port, auth
+        return callrpc_xmr(port, auth, method, params)
+    return rpc_func
+
--- a/basicswap/util.py
+++ b/basicswap/util.py
@ -9,12 +9,15 @@ import json
 import hashlib
 from .contrib.segwit_addr import bech32_decode, convertbits, bech32_encode

+OP_1 = 0x51
+OP_16 = 0x60
 COIN = 100000000
 DCOIN = decimal.Decimal(COIN)


-def makeInt(v):
-    return int(dquantize(decimal.Decimal(v) * DCOIN).quantize(decimal.Decimal(1)))
+def assert_cond(v, err='Bad opcode'):
+    if not v:
+        raise ValueError(err)


 def format8(i):
@ -188,3 +191,105 @@ def DeserialiseNum(b, o=0):
    if b[o + nb - 1] & 0x80:
        return -(v & ~(0x80 << (8 * (nb - 1))))
    return v
+
+
+def decodeScriptNum(script_bytes, o):
+    v = 0
+    num_len = script_bytes[o]
+    if num_len >= OP_1 and num_len <= OP_16:
+        return((num_len - OP_1) + 1, 1)
+
+    if num_len > 4:
+        raise ValueError('Bad scriptnum length')  # Max 4 bytes
+    if num_len + o >= len(script_bytes):
+        raise ValueError('Bad script length')
+    o += 1
+    for i in range(num_len):
+        b = script_bytes[o + i]
+        # Negative flag set in last byte, if num is positive and > 0x80 an extra 0x00 byte will be appended
+        if i == num_len - 1 and b & 0x80:
+            b &= (~(0x80) & 0xFF)
+            v += int(b) << 8 * i
+            v *= -1
+        else:
+            v += int(b) << 8 * i
+    return(v, 1 + num_len)
+
+
+def getCompactSizeLen(v):
+    # Compact Size
+    if v < 253:
+        return 1
+    if v < 0xffff:  # USHRT_MAX
+        return 3
+    if v < 0xffffffff:  # UINT_MAX
+        return 5
+    if v < 0xffffffffffffffff:  # UINT_MAX
+        return 9
+    raise ValueError('Value too large')
+
+
+def make_int(v, precision=8, r=0):  # r = 0, no rounding, fail, r > 0 round up, r < 0 floor
+    if type(v) == float:
+        v = str(v)
+    elif type(v) == int:
+        return v * 10 ** precision
+
+    ep = 10 ** precision
+    have_dp = False
+    rv = 0
+    for c in v:
+        if c == '.':
+            rv *= ep
+            have_dp = True
+            continue
+        if not c.isdigit():
+            raise ValueError('Invalid char')
+        if have_dp:
+            ep //= 10
+            if ep <= 0:
+                if r == 0:
+                    raise ValueError('Mantissa too long')
+                if r > 0:
+                    # Round up
+                    if int(c) > 4:
+                        rv += 1
+                break
+
+            rv += ep * int(c)
+        else:
+            rv = rv * 10 + int(c)
+    if not have_dp:
+        rv *= ep
+    return rv
+
+
+def validate_amount(amount, precision=8):
+    str_amount = str(amount)
+    has_decimal = False
+    for c in str_amount:
+        if c == '.' and not has_decimal:
+            has_decimal = True
+            continue
+        if not c.isdigit():
+            raise ValueError('Invalid amount')
+
+    ar = str_amount.split('.')
+    if len(ar) > 1 and len(ar[1]) > precision:
+        raise ValueError('Too many decimal places in amount {}'.format(str_amount))
+    return True
+
+
+def format_amount(i, display_precision, precision=None):
+    if precision is None:
+        precision = display_precision
+    ep = 10 ** precision
+    n = abs(i)
+    quotient = n // ep
+    remainder = n % ep
+    if display_precision != precision:
+        remainder %= (10 ** display_precision)
+    rv = '{}.{:0>{prec}}'.format(quotient, remainder, prec=display_precision)
+    if i < 0:
+        rv = '-' + rv
+    return rv
--- a/basicswap/util_xmr.py
+++ b/basicswap/util_xmr.py
@ -0,0 +1,17 @@
+# -*- coding: utf-8 -*-
+
+import xmrswap.contrib.Keccak as Keccak
+from .contrib.MoneroPy.base58 import encode as xmr_b58encode
+
+
+def cn_fast_hash(s):
+    k = Keccak.Keccak()
+    return k.Keccak((len(s) * 8, s.hex()), 1088, 512, 32 * 8, False).lower()  # r = bitrate = 1088, c = capacity, n = output length in bits
+
+
+def encode_address(view_point, spend_point, version=18):
+    buf = bytes((version,)) + spend_point + view_point
+    h = cn_fast_hash(buf)
+    buf = buf + bytes.fromhex(h[0: 8])
+
+    return xmr_b58encode(buf.hex())
--- a/setup.py
+++ b/setup.py
@ -29,6 +29,7 @@ setuptools.setup(
        "sqlalchemy",
        "python-gnupg",
        "Jinja2",
+        "requests",
    ],
    entry_points={
        "console_scripts": [
--- a/tests/basicswap/init.py
+++ b/tests/basicswap/init.py
@ -4,6 +4,7 @@ import tests.basicswap.test_other as test_other
 import tests.basicswap.test_prepare as test_prepare
 import tests.basicswap.test_run as test_run
 import tests.basicswap.test_reload as test_reload
+import tests.basicswap.test_xmr as test_xmr


 def test_suite():
@ -12,5 +13,6 @@ def test_suite():
    suite.addTests(loader.loadTestsFromModule(test_prepare))
    suite.addTests(loader.loadTestsFromModule(test_run))
    suite.addTests(loader.loadTestsFromModule(test_reload))
+    suite.addTests(loader.loadTestsFromModule(test_xmr))

    return suite
--- a/tests/basicswap/common.py
+++ b/tests/basicswap/common.py
@ -0,0 +1,14 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+# Copyright (c) 2020 tecnovert
+# Distributed under the MIT software license, see the accompanying
+# file LICENSE.txt or http://www.opensource.org/licenses/mit-license.php.
+
+def checkForks(ro):
+    if 'bip9_softforks' in ro:
+        assert(ro['bip9_softforks']['csv']['status'] == 'active')
+        assert(ro['bip9_softforks']['segwit']['status'] == 'active')
+    else:
+        assert(ro['softforks']['csv']['active'])
+        assert(ro['softforks']['segwit']['active'])
--- a/tests/basicswap/test_other.py
+++ b/tests/basicswap/test_other.py
@ -9,7 +9,7 @@ import unittest
 from basicswap.util import (
    SerialiseNum,
    DeserialiseNum,
-    makeInt,
+    make_int,
    format8,
 )
 from basicswap.basicswap import (
@ -57,19 +57,28 @@ class Test(unittest.TestCase):
        decoded = decodeSequence(encoded)
        assert(decoded == blocks_val)

-    def test_makeInt(self):
+    def test_make_int(self):
        def test_case(vs, vf, expect_int):
-            assert(makeInt(vs) == expect_int)
-            assert(makeInt(vf) == expect_int)
-            vs_out = format8(makeInt(vs))
+            i = make_int(vs)
+            assert(i == expect_int and isinstance(i, int))
+            i = make_int(vf)
+            assert(i == expect_int and isinstance(i, int))
+            vs_out = format_amount(i, 8)
            # Strip
            for i in range(7):
                if vs_out[-1] == '0':
                    vs_out = vs_out[:-1]
-            assert(vs_out == vs)
+            if '.' in vs:
+                assert(vs_out == vs)
+            else:
+                assert(vs_out[:-2] == vs)
+        test_case('0', 0, 0)
+        test_case('1', 1, 100000000)
+        test_case('10', 10, 1000000000)
        test_case('0.00899999', 0.00899999, 899999)
        test_case('899999.0', 899999.0, 89999900000000)
        test_case('899999.00899999', 899999.00899999, 89999900899999)
+        test_case('0.0', 0.0, 0)
        test_case('1.0', 1.0, 100000000)
        test_case('1.1', 1.1, 110000000)
        test_case('1.2', 1.2, 120000000)
@ -79,6 +88,52 @@ class Test(unittest.TestCase):
        test_case('0.123', 0.123, 12300000)
        test_case('123000.000123', 123000.000123, 12300000012300)

+        try:
+            make_int('0.123456789')
+            assert(False)
+        except Exception as e:
+            assert(str(e) == 'Mantissa too long')
+        validate_amount('0.12345678')
+
+        # floor
+        assert(make_int('0.123456789', r=-1) == 12345678)
+        # Round up
+        assert(make_int('0.123456789', r=1) == 12345679)
+
+    def test_make_int12(self):
+        def test_case(vs, vf, expect_int):
+            i = make_int(vs, 12)
+            assert(i == expect_int and isinstance(i, int))
+            i = make_int(vf, 12)
+            assert(i == expect_int and isinstance(i, int))
+            vs_out = format_amount(i, 12)
+            # Strip
+            for i in range(7):
+                if vs_out[-1] == '0':
+                    vs_out = vs_out[:-1]
+            if '.' in vs:
+                assert(vs_out == vs)
+            else:
+                assert(vs_out[:-2] == vs)
+        test_case('0.123456789', 0.123456789, 123456789000)
+        test_case('0.123456789123', 0.123456789123, 123456789123)
+        try:
+            make_int('0.1234567891234', 12)
+            assert(False)
+        except Exception as e:
+            assert(str(e) == 'Mantissa too long')
+        validate_amount('0.123456789123', 12)
+        try:
+            validate_amount('0.1234567891234', 12)
+            assert(False)
+        except Exception as e:
+            assert('Too many decimal places' in str(e))
+        try:
+            validate_amount(0.1234567891234, 12)
+            assert(False)
+        except Exception as e:
+            assert('Too many decimal places' in str(e))
+

 if __name__ == '__main__':
    unittest.main()
--- a/tests/basicswap/test_run.py
+++ b/tests/basicswap/test_run.py
@ -48,6 +48,9 @@ from basicswap.contrib.key import (
 from basicswap.http_server import (
    HttpThread,
 )
+from tests.basicswap.common import (
+    checkForks,
+)
 from bin.basicswap_run import startDaemon

 logger = logging.getLogger()
@ -205,15 +208,6 @@ def run_loop(self):
        btcRpc('generatetoaddress 1 {}'.format(self.btc_addr))


-def checkForks(ro):
-    if 'bip9_softforks' in ro:
-        assert(ro['bip9_softforks']['csv']['status'] == 'active')
-        assert(ro['bip9_softforks']['segwit']['status'] == 'active')
-    else:
-        assert(ro['softforks']['csv']['active'])
-        assert(ro['softforks']['segwit']['active'])
-
-
 class Test(unittest.TestCase):

    @classmethod
--- a/tests/basicswap/test_xmr.py
+++ b/tests/basicswap/test_xmr.py
@ -0,0 +1,246 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+# Copyright (c) 2020 tecnovert
+# Distributed under the MIT software license, see the accompanying
+# file LICENSE or http://www.opensource.org/licenses/mit-license.php.
+
+import os
+import sys
+import unittest
+import json
+import logging
+import shutil
+import time
+import signal
+import threading
+from urllib.request import urlopen
+from coincurve.ecdsaotves import (
+    ecdsaotves_enc_sign,
+    ecdsaotves_enc_verify,
+    ecdsaotves_dec_sig,
+    ecdsaotves_rec_enc_key)
+from coincurve.dleag import (
+    dleag_prove,
+    dleag_verify)
+
+import basicswap.config as cfg
+from basicswap.basicswap import (
+    BasicSwap,
+    Coins,
+    SwapTypes,
+    BidStates,
+    TxStates,
+    SEQUENCE_LOCK_BLOCKS,
+)
+from basicswap.util import (
+    COIN,
+    toWIF,
+    dumpje,
+)
+from basicswap.rpc import (
+    callrpc_cli,
+    waitForRPC,
+)
+from basicswap.contrib.key import (
+    ECKey,
+)
+from basicswap.http_server import (
+    HttpThread,
+)
+from bin.basicswap_run import startDaemon
+
+logger = logging.getLogger()
+logger.level = logging.DEBUG
+if not len(logger.handlers):
+    logger.addHandler(logging.StreamHandler(sys.stdout))
+
+NUM_NODES = 3
+BASE_PORT = 14792
+BASE_RPC_PORT = 19792
+BASE_ZMQ_PORT = 20792
+PREFIX_SECRET_KEY_REGTEST = 0x2e
+TEST_HTML_PORT = 1800
+stop_test = False
+
+
+
+def prepareOtherDir(datadir, nodeId, conf_file='litecoin.conf'):
+    node_dir = os.path.join(datadir, str(nodeId))
+    if not os.path.exists(node_dir):
+        os.makedirs(node_dir)
+    filePath = os.path.join(node_dir, conf_file)
+
+    with open(filePath, 'w+') as fp:
+        fp.write('regtest=1\n')
+        fp.write('[regtest]\n')
+        fp.write('port=' + str(BASE_PORT + nodeId) + '\n')
+        fp.write('rpcport=' + str(BASE_RPC_PORT + nodeId) + '\n')
+
+        fp.write('daemon=0\n')
+        fp.write('printtoconsole=0\n')
+        fp.write('server=1\n')
+        fp.write('discover=0\n')
+        fp.write('listenonion=0\n')
+        fp.write('bind=127.0.0.1\n')
+        fp.write('findpeers=0\n')
+        fp.write('debug=1\n')
+        fp.write('debugexclude=libevent\n')
+        fp.write('fallbackfee=0.0002\n')
+
+        fp.write('acceptnonstdtxn=0\n')
+
+
+def prepareDir(datadir, nodeId, network_key, network_pubkey):
+    node_dir = os.path.join(datadir, str(nodeId))
+    if not os.path.exists(node_dir):
+        os.makedirs(node_dir)
+    filePath = os.path.join(node_dir, 'particl.conf')
+
+    with open(filePath, 'w+') as fp:
+        fp.write('regtest=1\n')
+        fp.write('[regtest]\n')
+        fp.write('port=' + str(BASE_PORT + nodeId) + '\n')
+        fp.write('rpcport=' + str(BASE_RPC_PORT + nodeId) + '\n')
+
+        fp.write('daemon=0\n')
+        fp.write('printtoconsole=0\n')
+        fp.write('server=1\n')
+        fp.write('discover=0\n')
+        fp.write('listenonion=0\n')
+        fp.write('bind=127.0.0.1\n')
+        fp.write('findpeers=0\n')
+        fp.write('debug=1\n')
+        fp.write('debugexclude=libevent\n')
+        fp.write('zmqpubsmsg=tcp://127.0.0.1:' + str(BASE_ZMQ_PORT + nodeId) + '\n')
+
+        fp.write('acceptnonstdtxn=0\n')
+        fp.write('minstakeinterval=5\n')
+
+        for i in range(0, NUM_NODES):
+            if nodeId == i:
+                continue
+            fp.write('addnode=127.0.0.1:%d\n' % (BASE_PORT + i))
+
+        if nodeId < 2:
+            fp.write('spentindex=1\n')
+            fp.write('txindex=1\n')
+
+    basicswap_dir = os.path.join(datadir, str(nodeId), 'basicswap')
+    if not os.path.exists(basicswap_dir):
+        os.makedirs(basicswap_dir)
+
+    ltcdatadir = os.path.join(datadir, str(LTC_NODE))
+    btcdatadir = os.path.join(datadir, str(BTC_NODE))
+    settings_path = os.path.join(basicswap_dir, cfg.CONFIG_FILENAME)
+    settings = {
+        'zmqhost': 'tcp://127.0.0.1',
+        'zmqport': BASE_ZMQ_PORT + nodeId,
+        'htmlhost': 'localhost',
+        'htmlport': 12700 + nodeId,
+        'network_key': network_key,
+        'network_pubkey': network_pubkey,
+        'chainclients': {
+            'particl': {
+                'connection_type': 'rpc',
+                'manage_daemon': False,
+                'rpcport': BASE_RPC_PORT + nodeId,
+                'datadir': node_dir,
+                'bindir': cfg.PARTICL_BINDIR,
+                'blocks_confirmed': 2,  # Faster testing
+            },
+            'litecoin': {
+                'connection_type': 'rpc',
+                'manage_daemon': False,
+                'rpcport': BASE_RPC_PORT + LTC_NODE,
+                'datadir': ltcdatadir,
+                'bindir': cfg.LITECOIN_BINDIR,
+                # 'use_segwit': True,
+            },
+            'bitcoin': {
+                'connection_type': 'rpc',
+                'manage_daemon': False,
+                'rpcport': BASE_RPC_PORT + BTC_NODE,
+                'datadir': btcdatadir,
+                'bindir': cfg.BITCOIN_BINDIR,
+                'use_segwit': True,
+            }
+        },
+        'check_progress_seconds': 2,
+        'check_watched_seconds': 4,
+        'check_expired_seconds': 60,
+        'check_events_seconds': 1,
+        'min_delay_auto_accept': 1,
+        'max_delay_auto_accept': 5
+    }
+    with open(settings_path, 'w') as fp:
+        json.dump(settings, fp, indent=4)
+
+
+def partRpc(cmd, node_id=0):
+    return callrpc_cli(cfg.PARTICL_BINDIR, os.path.join(cfg.TEST_DATADIRS, str(node_id)), 'regtest', cmd, cfg.PARTICL_CLI)
+
+
+def btcRpc(cmd):
+    return callrpc_cli(cfg.BITCOIN_BINDIR, os.path.join(cfg.TEST_DATADIRS, str(BTC_NODE)), 'regtest', cmd, cfg.BITCOIN_CLI)
+
+
+def signal_handler(sig, frame):
+    global stop_test
+    print('signal {} detected.'.format(sig))
+    stop_test = True
+
+
+def run_loop(self):
+    while not stop_test:
+        time.sleep(1)
+        for c in self.swap_clients:
+            c.update()
+        btcRpc('generatetoaddress 1 {}'.format(self.btc_addr))
+
+
+def checkForks(ro):
+    if 'bip9_softforks' in ro:
+        assert(ro['bip9_softforks']['csv']['status'] == 'active')
+        assert(ro['bip9_softforks']['segwit']['status'] == 'active')
+    else:
+        assert(ro['softforks']['csv']['active'])
+        assert(ro['softforks']['segwit']['active'])
+
+
+class Test(unittest.TestCase):
+
+    @classmethod
+    def setUpClass(cls):
+        super(Test, cls).setUpClass()
+
+        cls.swap_clients = []
+        cls.xmr_daemons = []
+        cls.xmr_wallet_auth = []
+
+        cls.part_stakelimit = 0
+        cls.xmr_addr = None
+
+        signal.signal(signal.SIGINT, signal_handler)
+        cls.update_thread = threading.Thread(target=run_loop, args=(cls,))
+        cls.update_thread.start()
+
+    @classmethod
+    def tearDownClass(cls):
+        global stop_test
+        logging.info('Finalising')
+        stop_test = True
+        cls.update_thread.join()
+
+        super(Test, cls).tearDownClass()
+
+    def test_01_part_xmr(self):
+        logging.info('---------- Test PART to XMR')
+        #swap_clients = self.swap_clients
+
+        #offer_id = swap_clients[0].postOffer(Coins.PART, Coins.XMR, 100 * COIN, 0.5 * COIN, 100 * COIN, SwapTypes.SELLER_FIRST)
+
+
+
+if __name__ == '__main__':
+    unittest.main()