diff --git a/test/functional/p2p_invalid_tx.py b/test/functional/p2p_invalid_tx.py
index 8a9bb0d6f3..a9aeca2437 100755
--- a/test/functional/p2p_invalid_tx.py
+++ b/test/functional/p2p_invalid_tx.py
@@ -1,86 +1,65 @@
 #!/usr/bin/env python3
-# Copyright (c) 2015-2016 The Bitcoin Core developers
+# Copyright (c) 2015-2017 The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 """Test node responses to invalid transactions.
 
 In this test we connect to one node over p2p, and test tx requests.
 """
 
-import time
-
 from test_framework.blocktools import (
     create_block,
     create_coinbase,
     create_transaction,
 )
-from test_framework.comptool import RejectResult, TestInstance, TestManager
 from test_framework.messages import COIN
-from test_framework.mininode import network_thread_start
-from test_framework.test_framework import ComparisonTestFramework
-
-
-# Use the ComparisonTestFramework with 1 node: only use --testbinary.
+from test_framework.mininode import network_thread_start, P2PDataStore
+from test_framework.test_framework import BitcoinTestFramework
 
 
-class InvalidTxRequestTest(ComparisonTestFramework):
-
-    ''' Can either run this test as 1 node with expected answers, or two and compare them. 
-        Change the "outcome" variable from each TestInstance object to only do the comparison. '''
+class InvalidTxRequestTest(BitcoinTestFramework):
 
     def set_test_params(self):
         self.num_nodes = 1
         self.setup_clean_chain = True
+        self.extra_args = [["-whitelist=127.0.0.1"]]
 
     def run_test(self):
-        test = TestManager(self, self.options.tmpdir)
-        test.add_all_connections(self.nodes)
-        self.tip = None
-        self.block_time = None
+        # Add p2p connection to node0
+        # convenience reference to the node
+        node = self.nodes[0]
+        node.add_p2p_connection(P2PDataStore())
+
         network_thread_start()
-        test.run()
+        node.p2p.wait_for_verack()
 
-    def get_tests(self):
-        if self.tip is None:
-            self.tip = int("0x" + self.nodes[0].getbestblockhash(), 0)
-        self.block_time = int(time.time()) + 1
+        best_block = self.nodes[0].getbestblockhash()
+        tip = int(best_block, 16)
+        best_block_time = self.nodes[0].getblock(best_block)['time']
+        block_time = best_block_time + 1
 
-        '''
-        Create a new block with an anyone-can-spend coinbase
-        '''
+        self.log.info("Create a new block with an anyone-can-spend coinbase.")
         height = 1
-        block = create_block(
-            self.tip, create_coinbase(height), self.block_time)
-        self.block_time += 1
+        block = create_block(tip, create_coinbase(height), block_time)
+        block_time += 1
         block.solve()
         # Save the coinbase for later
-        self.block1 = block
-        self.tip = block.sha256
+        block1 = block
+        tip = block.sha256
         height += 1
-        yield TestInstance([[block, True]])
+        node.p2p.send_blocks_and_test([block], node, success=True)
 
-        '''
-        Now we need that block to mature so we can spend the coinbase.
-        '''
-        test = TestInstance(sync_every_block=False)
-        for i in range(100):
-            block = create_block(
-                self.tip, create_coinbase(height), self.block_time)
-            block.solve()
-            self.tip = block.sha256
-            self.block_time += 1
-            test.blocks_and_transactions.append([block, True])
-            height += 1
-        yield test
+        self.log.info("Mature the block.")
+        self.nodes[0].generate(100)
 
         # b'\x64' is OP_NOTIF
         # Transaction will be rejected with code 16 (REJECT_INVALID)
-        tx1 = create_transaction(
-            self.block1.vtx[0], 0, b'\x64', 50 * COIN - 12000)
-        yield TestInstance([[tx1, RejectResult(16, b'mandatory-script-verify-flag-failed')]])
+        tx1 = create_transaction(block1.vtx[0], 0, b'\x64', 50 * COIN - 12000)
+        node.p2p.send_txs_and_test([tx1], node, success=False, reject_code=16,
+                                   reject_reason=b'mandatory-script-verify-flag-failed (Only push operators allowed in signature scripts)')
 
         # TODO: test further transactions...
 
 
 if __name__ == '__main__':
     InvalidTxRequestTest().main()
diff --git a/test/functional/test_framework/messages.py b/test/functional/test_framework/messages.py
index 73640ad73c..0de024e0bd 100755
--- a/test/functional/test_framework/messages.py
+++ b/test/functional/test_framework/messages.py
@@ -1,1252 +1,1256 @@
 #!/usr/bin/env python3
 # Copyright (c) 2010 ArtForz -- public domain half-a-node
 # Copyright (c) 2012 Jeff Garzik
 # Copyright (c) 2010-2017 The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 """Bitcoin test framework primitive and message strcutures
 
 CBlock, CTransaction, CBlockHeader, CTxIn, CTxOut, etc....:
     data structures that should map to corresponding structures in
     bitcoin/primitives
 
 msg_block, msg_tx, msg_headers, etc.:
     data structures that represent network messages
 
 ser_*, deser_*: functions that handle serialization/deserialization."""
 from codecs import encode
 import copy
 import hashlib
 from io import BytesIO
 import random
 import socket
 import struct
 import time
 
 from test_framework.siphash import siphash256
 from test_framework.util import bytes_to_hex_str, hex_str_to_bytes
 
 MIN_VERSION_SUPPORTED = 60001
 # past bip-31 for ping/pong
 MY_VERSION = 70014
 MY_SUBVERSION = b"/python-mininode-tester:0.0.3/"
 # from version 70001 onwards, fRelay should be appended to version messages (BIP37)
 MY_RELAY = 1
 
 MAX_INV_SZ = 50000
 MAX_BLOCK_BASE_SIZE = 1000000
 
 # 1 BCH in satoshis
 COIN = 100000000
 
 NODE_NETWORK = (1 << 0)
 # NODE_GETUTXO = (1 << 1)
 NODE_BLOOM = (1 << 2)
 # NODE_WITNESS = (1 << 3)
 NODE_XTHIN = (1 << 4)
 NODE_BITCOIN_CASH = (1 << 5)
 NODE_NETWORK_LIMITED = (1 << 10)
 
+MSG_TX = 1
+MSG_BLOCK = 2
+MSG_TYPE_MASK = 0xffffffff >> 2
+
 # Howmuch data will be read from the network at once
 READ_BUFFER_SIZE = 8192
 
 # Serialization/deserialization tools
 
 
 def sha256(s):
     return hashlib.new('sha256', s).digest()
 
 
 def ripemd160(s):
     return hashlib.new('ripemd160', s).digest()
 
 
 def hash256(s):
     return sha256(sha256(s))
 
 
 def ser_compact_size(l):
     r = b""
     if l < 253:
         r = struct.pack("B", l)
     elif l < 0x10000:
         r = struct.pack("<BH", 253, l)
     elif l < 0x100000000:
         r = struct.pack("<BI", 254, l)
     else:
         r = struct.pack("<BQ", 255, l)
     return r
 
 
 def deser_compact_size(f):
     nit = struct.unpack("<B", f.read(1))[0]
     if nit == 253:
         nit = struct.unpack("<H", f.read(2))[0]
     elif nit == 254:
         nit = struct.unpack("<I", f.read(4))[0]
     elif nit == 255:
         nit = struct.unpack("<Q", f.read(8))[0]
     return nit
 
 
 def deser_string(f):
     nit = deser_compact_size(f)
     return f.read(nit)
 
 
 def ser_string(s):
     return ser_compact_size(len(s)) + s
 
 
 def deser_uint256(f):
     r = 0
     for i in range(8):
         t = struct.unpack("<I", f.read(4))[0]
         r += t << (i * 32)
     return r
 
 
 def ser_uint256(u):
     rs = b""
     for i in range(8):
         rs += struct.pack("<I", u & 0xFFFFFFFF)
         u >>= 32
     return rs
 
 
 def uint256_from_str(s):
     r = 0
     t = struct.unpack("<IIIIIIII", s[:32])
     for i in range(8):
         r += t[i] << (i * 32)
     return r
 
 
 def uint256_from_compact(c):
     nbytes = (c >> 24) & 0xFF
     v = (c & 0xFFFFFF) << (8 * (nbytes - 3))
     return v
 
 
 def deser_vector(f, c):
     nit = deser_compact_size(f)
     r = []
     for i in range(nit):
         t = c()
         t.deserialize(f)
         r.append(t)
     return r
 
 
 # ser_function_name: Allow for an alternate serialization function on the
 # entries in the vector.
 def ser_vector(l, ser_function_name=None):
     r = ser_compact_size(len(l))
     for i in l:
         if ser_function_name:
             r += getattr(i, ser_function_name)()
         else:
             r += i.serialize()
     return r
 
 
 def deser_uint256_vector(f):
     nit = deser_compact_size(f)
     r = []
     for i in range(nit):
         t = deser_uint256(f)
         r.append(t)
     return r
 
 
 def ser_uint256_vector(l):
     r = ser_compact_size(len(l))
     for i in l:
         r += ser_uint256(i)
     return r
 
 
 def deser_string_vector(f):
     nit = deser_compact_size(f)
     r = []
     for i in range(nit):
         t = deser_string(f)
         r.append(t)
     return r
 
 
 def ser_string_vector(l):
     r = ser_compact_size(len(l))
     for sv in l:
         r += ser_string(sv)
     return r
 
 
 # Deserialize from a hex string representation (eg from RPC)
 
 
 def FromHex(obj, hex_string):
     obj.deserialize(BytesIO(hex_str_to_bytes(hex_string)))
     return obj
 
 # Convert a binary-serializable object to hex (eg for submission via RPC)
 
 
 def ToHex(obj):
     return bytes_to_hex_str(obj.serialize())
 
 # Objects that map to bitcoind objects, which can be serialized/deserialized
 
 
 class CAddress():
     def __init__(self):
         self.time = 0
         self.nServices = 1
         self.pchReserved = b"\x00" * 10 + b"\xff" * 2
         self.ip = "0.0.0.0"
         self.port = 0
 
     def deserialize(self, f, with_time=True):
         if with_time:
             self.time = struct.unpack("<i", f.read(4))[0]
         self.nServices = struct.unpack("<Q", f.read(8))[0]
         self.pchReserved = f.read(12)
         self.ip = socket.inet_ntoa(f.read(4))
         self.port = struct.unpack(">H", f.read(2))[0]
 
     def serialize(self, with_time=True):
         r = b""
         if with_time:
             r += struct.pack("<i", self.time)
         r += struct.pack("<Q", self.nServices)
         r += self.pchReserved
         r += socket.inet_aton(self.ip)
         r += struct.pack(">H", self.port)
         return r
 
     def __repr__(self):
         return "CAddress(nServices={} ip={} port={})".format(
             self.nServices, self.ip, self.port)
 
 
 class CInv():
     typemap = {
         0: "Error",
         1: "TX",
         2: "Block",
         4: "CompactBlock"
     }
 
     def __init__(self, t=0, h=0):
         self.type = t
         self.hash = h
 
     def deserialize(self, f):
         self.type = struct.unpack("<i", f.read(4))[0]
         self.hash = deser_uint256(f)
 
     def serialize(self):
         r = b""
         r += struct.pack("<i", self.type)
         r += ser_uint256(self.hash)
         return r
 
     def __repr__(self):
         return "CInv(type={} hash={:064x})".format(
             self.typemap[self.type], self.hash)
 
 
 class CBlockLocator():
     def __init__(self):
         self.nVersion = MY_VERSION
         self.vHave = []
 
     def deserialize(self, f):
         self.nVersion = struct.unpack("<i", f.read(4))[0]
         self.vHave = deser_uint256_vector(f)
 
     def serialize(self):
         r = b""
         r += struct.pack("<i", self.nVersion)
         r += ser_uint256_vector(self.vHave)
         return r
 
     def __repr__(self):
         return "CBlockLocator(nVersion={} vHave={})".format(
             self.nVersion, repr(self.vHave))
 
 
 class COutPoint():
     def __init__(self, hash=0, n=0):
         self.hash = hash
         self.n = n
 
     def deserialize(self, f):
         self.hash = deser_uint256(f)
         self.n = struct.unpack("<I", f.read(4))[0]
 
     def serialize(self):
         r = b""
         r += ser_uint256(self.hash)
         r += struct.pack("<I", self.n)
         return r
 
     def __repr__(self):
         return "COutPoint(hash={:064x} n={})".format(self.hash, self.n)
 
 
 class CTxIn():
     def __init__(self, outpoint=None, scriptSig=b"", nSequence=0):
         if outpoint is None:
             self.prevout = COutPoint()
         else:
             self.prevout = outpoint
         self.scriptSig = scriptSig
         self.nSequence = nSequence
 
     def deserialize(self, f):
         self.prevout = COutPoint()
         self.prevout.deserialize(f)
         self.scriptSig = deser_string(f)
         self.nSequence = struct.unpack("<I", f.read(4))[0]
 
     def serialize(self):
         r = b""
         r += self.prevout.serialize()
         r += ser_string(self.scriptSig)
         r += struct.pack("<I", self.nSequence)
         return r
 
     def __repr__(self):
         return "CTxIn(prevout={} scriptSig={} nSequence={})".format(
             repr(self.prevout), bytes_to_hex_str(self.scriptSig), self.nSequence)
 
 
 class CTxOut():
     def __init__(self, nValue=0, scriptPubKey=b""):
         self.nValue = nValue
         self.scriptPubKey = scriptPubKey
 
     def deserialize(self, f):
         self.nValue = struct.unpack("<q", f.read(8))[0]
         self.scriptPubKey = deser_string(f)
 
     def serialize(self):
         r = b""
         r += struct.pack("<q", self.nValue)
         r += ser_string(self.scriptPubKey)
         return r
 
     def __repr__(self):
         return "CTxOut(nValue={}.{:08d} scriptPubKey={})".format(
             self.nValue // COIN, self.nValue % COIN,
             bytes_to_hex_str(self.scriptPubKey))
 
 
 class CTransaction():
     def __init__(self, tx=None):
         if tx is None:
             self.nVersion = 1
             self.vin = []
             self.vout = []
             self.nLockTime = 0
             self.sha256 = None
             self.hash = None
         else:
             self.nVersion = tx.nVersion
             self.vin = copy.deepcopy(tx.vin)
             self.vout = copy.deepcopy(tx.vout)
             self.nLockTime = tx.nLockTime
             self.sha256 = tx.sha256
             self.hash = tx.hash
 
     def deserialize(self, f):
         self.nVersion = struct.unpack("<i", f.read(4))[0]
         self.vin = deser_vector(f, CTxIn)
         self.vout = deser_vector(f, CTxOut)
         self.nLockTime = struct.unpack("<I", f.read(4))[0]
         self.sha256 = None
         self.hash = None
 
     def billable_size(self):
         """
         Returns the size used for billing the against the transaction
         """
         return len(self.serialize())
 
     def serialize(self):
         r = b""
         r += struct.pack("<i", self.nVersion)
         r += ser_vector(self.vin)
         r += ser_vector(self.vout)
         r += struct.pack("<I", self.nLockTime)
         return r
 
     # Recalculate the txid
     def rehash(self):
         self.sha256 = None
         self.calc_sha256()
         return self.hash
 
     # self.sha256 and self.hash -- those are expected to be the txid.
     def calc_sha256(self):
         if self.sha256 is None:
             self.sha256 = uint256_from_str(hash256(self.serialize()))
         self.hash = encode(
             hash256(self.serialize())[::-1], 'hex_codec').decode('ascii')
 
     def get_id(self):
         # For now, just forward the hash.
         self.calc_sha256()
         return self.hash
 
     def is_valid(self):
         self.calc_sha256()
         for tout in self.vout:
             if tout.nValue < 0 or tout.nValue > 21000000 * COIN:
                 return False
         return True
 
     def __repr__(self):
         return "CTransaction(nVersion={} vin={} vout={} nLockTime={})".format(
             self.nVersion, repr(self.vin), repr(self.vout), self.nLockTime)
 
 
 class CBlockHeader():
     def __init__(self, header=None):
         if header is None:
             self.set_null()
         else:
             self.nVersion = header.nVersion
             self.hashPrevBlock = header.hashPrevBlock
             self.hashMerkleRoot = header.hashMerkleRoot
             self.nTime = header.nTime
             self.nBits = header.nBits
             self.nNonce = header.nNonce
             self.sha256 = header.sha256
             self.hash = header.hash
             self.calc_sha256()
 
     def set_null(self):
         self.nVersion = 1
         self.hashPrevBlock = 0
         self.hashMerkleRoot = 0
         self.nTime = 0
         self.nBits = 0
         self.nNonce = 0
         self.sha256 = None
         self.hash = None
 
     def deserialize(self, f):
         self.nVersion = struct.unpack("<i", f.read(4))[0]
         self.hashPrevBlock = deser_uint256(f)
         self.hashMerkleRoot = deser_uint256(f)
         self.nTime = struct.unpack("<I", f.read(4))[0]
         self.nBits = struct.unpack("<I", f.read(4))[0]
         self.nNonce = struct.unpack("<I", f.read(4))[0]
         self.sha256 = None
         self.hash = None
 
     def serialize(self):
         r = b""
         r += struct.pack("<i", self.nVersion)
         r += ser_uint256(self.hashPrevBlock)
         r += ser_uint256(self.hashMerkleRoot)
         r += struct.pack("<I", self.nTime)
         r += struct.pack("<I", self.nBits)
         r += struct.pack("<I", self.nNonce)
         return r
 
     def calc_sha256(self):
         if self.sha256 is None:
             r = b""
             r += struct.pack("<i", self.nVersion)
             r += ser_uint256(self.hashPrevBlock)
             r += ser_uint256(self.hashMerkleRoot)
             r += struct.pack("<I", self.nTime)
             r += struct.pack("<I", self.nBits)
             r += struct.pack("<I", self.nNonce)
             self.sha256 = uint256_from_str(hash256(r))
             self.hash = encode(hash256(r)[::-1], 'hex_codec').decode('ascii')
 
     def rehash(self):
         self.sha256 = None
         self.calc_sha256()
         return self.sha256
 
     def __repr__(self):
         return "CBlockHeader(nVersion={} hashPrevBlock={:064x} hashMerkleRoot={:064x} nTime={} nBits={:08x} nNonce={:08x})".format(
             self.nVersion, self.hashPrevBlock, self.hashMerkleRoot,
             time.ctime(self.nTime), self.nBits, self.nNonce)
 
 
 class CBlock(CBlockHeader):
     def __init__(self, header=None):
         super(CBlock, self).__init__(header)
         self.vtx = []
 
     def deserialize(self, f):
         super(CBlock, self).deserialize(f)
         self.vtx = deser_vector(f, CTransaction)
 
     def serialize(self):
         r = b""
         r += super(CBlock, self).serialize()
         r += ser_vector(self.vtx)
         return r
 
     # Calculate the merkle root given a vector of transaction hashes
     def get_merkle_root(self, hashes):
         while len(hashes) > 1:
             newhashes = []
             for i in range(0, len(hashes), 2):
                 i2 = min(i + 1, len(hashes) - 1)
                 newhashes.append(hash256(hashes[i] + hashes[i2]))
             hashes = newhashes
         return uint256_from_str(hashes[0])
 
     def calc_merkle_root(self):
         hashes = []
         for tx in self.vtx:
             tx.calc_sha256()
             hashes.append(ser_uint256(tx.sha256))
         return self.get_merkle_root(hashes)
 
     def is_valid(self):
         self.calc_sha256()
         target = uint256_from_compact(self.nBits)
         if self.sha256 > target:
             return False
         for tx in self.vtx:
             if not tx.is_valid():
                 return False
         if self.calc_merkle_root() != self.hashMerkleRoot:
             return False
         return True
 
     def solve(self):
         self.rehash()
         target = uint256_from_compact(self.nBits)
         while self.sha256 > target:
             self.nNonce += 1
             self.rehash()
 
     def __repr__(self):
         return "CBlock(nVersion={} hashPrevBlock={:064x} hashMerkleRoot={:064x} nTime={} nBits={:08x} nNonce={:08x} vtx={})".format(
             self.nVersion, self.hashPrevBlock, self.hashMerkleRoot,
             time.ctime(self.nTime), self.nBits, self.nNonce, repr(self.vtx))
 
 
 class PrefilledTransaction():
     def __init__(self, index=0, tx=None):
         self.index = index
         self.tx = tx
 
     def deserialize(self, f):
         self.index = deser_compact_size(f)
         self.tx = CTransaction()
         self.tx.deserialize(f)
 
     def serialize(self):
         r = b""
         r += ser_compact_size(self.index)
         r += self.tx.serialize()
         return r
 
     def __repr__(self):
         return "PrefilledTransaction(index={}, tx={})".format(
             self.index, repr(self.tx))
 
 # This is what we send on the wire, in a cmpctblock message.
 
 
 class P2PHeaderAndShortIDs():
     def __init__(self):
         self.header = CBlockHeader()
         self.nonce = 0
         self.shortids_length = 0
         self.shortids = []
         self.prefilled_txn_length = 0
         self.prefilled_txn = []
 
     def deserialize(self, f):
         self.header.deserialize(f)
         self.nonce = struct.unpack("<Q", f.read(8))[0]
         self.shortids_length = deser_compact_size(f)
         for i in range(self.shortids_length):
             # shortids are defined to be 6 bytes in the spec, so append
             # two zero bytes and read it in as an 8-byte number
             self.shortids.append(
                 struct.unpack("<Q", f.read(6) + b'\x00\x00')[0])
         self.prefilled_txn = deser_vector(f, PrefilledTransaction)
         self.prefilled_txn_length = len(self.prefilled_txn)
 
     def serialize(self):
         r = b""
         r += self.header.serialize()
         r += struct.pack("<Q", self.nonce)
         r += ser_compact_size(self.shortids_length)
         for x in self.shortids:
             # We only want the first 6 bytes
             r += struct.pack("<Q", x)[0:6]
         r += ser_vector(self.prefilled_txn)
         return r
 
     def __repr__(self):
         return "P2PHeaderAndShortIDs(header={}, nonce={}, shortids_length={}, shortids={}, prefilled_txn_length={}, prefilledtxn={}".format(
             repr(self.header), self.nonce, self.shortids_length,
             repr(self.shortids), self.prefilled_txn_length,
             repr(self.prefilled_txn))
 
 # Calculate the BIP 152-compact blocks shortid for a given transaction hash
 
 
 def calculate_shortid(k0, k1, tx_hash):
     expected_shortid = siphash256(k0, k1, tx_hash)
     expected_shortid &= 0x0000ffffffffffff
     return expected_shortid
 
 # This version gets rid of the array lengths, and reinterprets the differential
 # encoding into indices that can be used for lookup.
 
 
 class HeaderAndShortIDs():
     def __init__(self, p2pheaders_and_shortids=None):
         self.header = CBlockHeader()
         self.nonce = 0
         self.shortids = []
         self.prefilled_txn = []
 
         if p2pheaders_and_shortids != None:
             self.header = p2pheaders_and_shortids.header
             self.nonce = p2pheaders_and_shortids.nonce
             self.shortids = p2pheaders_and_shortids.shortids
             last_index = -1
             for x in p2pheaders_and_shortids.prefilled_txn:
                 self.prefilled_txn.append(
                     PrefilledTransaction(x.index + last_index + 1, x.tx))
                 last_index = self.prefilled_txn[-1].index
 
     def to_p2p(self):
         ret = P2PHeaderAndShortIDs()
         ret.header = self.header
         ret.nonce = self.nonce
         ret.shortids_length = len(self.shortids)
         ret.shortids = self.shortids
         ret.prefilled_txn_length = len(self.prefilled_txn)
         ret.prefilled_txn = []
         last_index = -1
         for x in self.prefilled_txn:
             ret.prefilled_txn.append(
                 PrefilledTransaction(x.index - last_index - 1, x.tx))
             last_index = x.index
         return ret
 
     def get_siphash_keys(self):
         header_nonce = self.header.serialize()
         header_nonce += struct.pack("<Q", self.nonce)
         hash_header_nonce_as_str = sha256(header_nonce)
         key0 = struct.unpack("<Q", hash_header_nonce_as_str[0:8])[0]
         key1 = struct.unpack("<Q", hash_header_nonce_as_str[8:16])[0]
         return [key0, key1]
 
     # Version 2 compact blocks use wtxid in shortids (rather than txid)
     def initialize_from_block(self, block, nonce=0, prefill_list=[0]):
         self.header = CBlockHeader(block)
         self.nonce = nonce
         self.prefilled_txn = [PrefilledTransaction(i, block.vtx[i])
                               for i in prefill_list]
         self.shortids = []
         [k0, k1] = self.get_siphash_keys()
         for i in range(len(block.vtx)):
             if i not in prefill_list:
                 tx_hash = block.vtx[i].sha256
                 self.shortids.append(calculate_shortid(k0, k1, tx_hash))
 
     def __repr__(self):
         return "HeaderAndShortIDs(header={}, nonce={}, shortids={}, prefilledtxn={}".format(
             repr(self.header), self.nonce, repr(self.shortids),
             repr(self.prefilled_txn))
 
 
 class BlockTransactionsRequest():
 
     def __init__(self, blockhash=0, indexes=None):
         self.blockhash = blockhash
         self.indexes = indexes if indexes != None else []
 
     def deserialize(self, f):
         self.blockhash = deser_uint256(f)
         indexes_length = deser_compact_size(f)
         for i in range(indexes_length):
             self.indexes.append(deser_compact_size(f))
 
     def serialize(self):
         r = b""
         r += ser_uint256(self.blockhash)
         r += ser_compact_size(len(self.indexes))
         for x in self.indexes:
             r += ser_compact_size(x)
         return r
 
     # helper to set the differentially encoded indexes from absolute ones
     def from_absolute(self, absolute_indexes):
         self.indexes = []
         last_index = -1
         for x in absolute_indexes:
             self.indexes.append(x - last_index - 1)
             last_index = x
 
     def to_absolute(self):
         absolute_indexes = []
         last_index = -1
         for x in self.indexes:
             absolute_indexes.append(x + last_index + 1)
             last_index = absolute_indexes[-1]
         return absolute_indexes
 
     def __repr__(self):
         return "BlockTransactionsRequest(hash={:064x} indexes={})".format(
             self.blockhash, repr(self.indexes))
 
 
 class BlockTransactions():
 
     def __init__(self, blockhash=0, transactions=None):
         self.blockhash = blockhash
         self.transactions = transactions if transactions != None else []
 
     def deserialize(self, f):
         self.blockhash = deser_uint256(f)
         self.transactions = deser_vector(f, CTransaction)
 
     def serialize(self):
         r = b""
         r += ser_uint256(self.blockhash)
         r += ser_vector(self.transactions)
         return r
 
     def __repr__(self):
         return "BlockTransactions(hash={:064x} transactions={})".format(
             self.blockhash, repr(self.transactions))
 
 
 class CPartialMerkleTree():
     def __init__(self):
         self.nTransactions = 0
         self.vHash = []
         self.vBits = []
         self.fBad = False
 
     def deserialize(self, f):
         self.nTransactions = struct.unpack("<i", f.read(4))[0]
         self.vHash = deser_uint256_vector(f)
         vBytes = deser_string(f)
         self.vBits = []
         for i in range(len(vBytes) * 8):
             self.vBits.append(vBytes[i // 8] & (1 << (i % 8)) != 0)
 
     def serialize(self):
         r = b""
         r += struct.pack("<i", self.nTransactions)
         r += ser_uint256_vector(self.vHash)
         vBytesArray = bytearray([0x00] * ((len(self.vBits) + 7) // 8))
         for i in range(len(self.vBits)):
             vBytesArray[i // 8] |= self.vBits[i] << (i % 8)
         r += ser_string(bytes(vBytesArray))
         return r
 
     def __repr__(self):
         return "CPartialMerkleTree(nTransactions={}, vHash={}, vBits={})".format(self.nTransactions, repr(self.vHash), repr(self.vBits))
 
 
 class CMerkleBlock():
     def __init__(self):
         self.header = CBlockHeader()
         self.txn = CPartialMerkleTree()
 
     def deserialize(self, f):
         self.header.deserialize(f)
         self.txn.deserialize(f)
 
     def serialize(self):
         r = b""
         r += self.header.serialize()
         r += self.txn.serialize()
         return r
 
     def __repr__(self):
         return "CMerkleBlock(header={}, txn={})".format(repr(self.header), repr(self.txn))
 
 
 # Objects that correspond to messages on the wire
 class msg_version():
     command = b"version"
 
     def __init__(self):
         self.nVersion = MY_VERSION
         self.nServices = 1
         self.nTime = int(time.time())
         self.addrTo = CAddress()
         self.addrFrom = CAddress()
         self.nNonce = random.getrandbits(64)
         self.strSubVer = MY_SUBVERSION
         self.nStartingHeight = -1
         self.nRelay = MY_RELAY
 
     def deserialize(self, f):
         self.nVersion = struct.unpack("<i", f.read(4))[0]
         if self.nVersion == 10300:
             self.nVersion = 300
         self.nServices = struct.unpack("<Q", f.read(8))[0]
         self.nTime = struct.unpack("<q", f.read(8))[0]
         self.addrTo = CAddress()
         self.addrTo.deserialize(f, False)
 
         if self.nVersion >= 106:
             self.addrFrom = CAddress()
             self.addrFrom.deserialize(f, False)
             self.nNonce = struct.unpack("<Q", f.read(8))[0]
             self.strSubVer = deser_string(f)
         else:
             self.addrFrom = None
             self.nNonce = None
             self.strSubVer = None
             self.nStartingHeight = None
 
         if self.nVersion >= 209:
             self.nStartingHeight = struct.unpack("<i", f.read(4))[0]
         else:
             self.nStartingHeight = None
 
         if self.nVersion >= 70001:
             # Relay field is optional for version 70001 onwards
             try:
                 self.nRelay = struct.unpack("<b", f.read(1))[0]
             except:
                 self.nRelay = 0
         else:
             self.nRelay = 0
 
     def serialize(self):
         r = b""
         r += struct.pack("<i", self.nVersion)
         r += struct.pack("<Q", self.nServices)
         r += struct.pack("<q", self.nTime)
         r += self.addrTo.serialize(False)
         r += self.addrFrom.serialize(False)
         r += struct.pack("<Q", self.nNonce)
         r += ser_string(self.strSubVer)
         r += struct.pack("<i", self.nStartingHeight)
         r += struct.pack("<b", self.nRelay)
         return r
 
     def __repr__(self):
         return 'msg_version(nVersion={} nServices={} nTime={} addrTo={} addrFrom={} nNonce=0x{:016X} strSubVer={} nStartingHeight={} nRelay={})'.format(
             self.nVersion, self.nServices, time.ctime(self.nTime),
             repr(self.addrTo), repr(self.addrFrom), self.nNonce,
             self.strSubVer, self.nStartingHeight, self.nRelay)
 
 
 class msg_verack():
     command = b"verack"
 
     def __init__(self):
         pass
 
     def deserialize(self, f):
         pass
 
     def serialize(self):
         return b""
 
     def __repr__(self):
         return "msg_verack()"
 
 
 class msg_addr():
     command = b"addr"
 
     def __init__(self):
         self.addrs = []
 
     def deserialize(self, f):
         self.addrs = deser_vector(f, CAddress)
 
     def serialize(self):
         return ser_vector(self.addrs)
 
     def __repr__(self):
         return "msg_addr(addrs={})".format(repr(self.addrs))
 
 
 class msg_inv():
     command = b"inv"
 
     def __init__(self, inv=None):
         if inv is None:
             self.inv = []
         else:
             self.inv = inv
 
     def deserialize(self, f):
         self.inv = deser_vector(f, CInv)
 
     def serialize(self):
         return ser_vector(self.inv)
 
     def __repr__(self):
         return "msg_inv(inv={})".format(repr(self.inv))
 
 
 class msg_getdata():
     command = b"getdata"
 
     def __init__(self, inv=None):
         self.inv = inv if inv != None else []
 
     def deserialize(self, f):
         self.inv = deser_vector(f, CInv)
 
     def serialize(self):
         return ser_vector(self.inv)
 
     def __repr__(self):
         return "msg_getdata(inv={})".format(repr(self.inv))
 
 
 class msg_getblocks():
     command = b"getblocks"
 
     def __init__(self):
         self.locator = CBlockLocator()
         self.hashstop = 0
 
     def deserialize(self, f):
         self.locator = CBlockLocator()
         self.locator.deserialize(f)
         self.hashstop = deser_uint256(f)
 
     def serialize(self):
         r = b""
         r += self.locator.serialize()
         r += ser_uint256(self.hashstop)
         return r
 
     def __repr__(self):
         return "msg_getblocks(locator={} hashstop={:064x})".format(
             repr(self.locator), self.hashstop)
 
 
 class msg_tx():
     command = b"tx"
 
     def __init__(self, tx=CTransaction()):
         self.tx = tx
 
     def deserialize(self, f):
         self.tx.deserialize(f)
 
     def serialize(self):
         return self.tx.serialize()
 
     def __repr__(self):
         return "msg_tx(tx={})".format(repr(self.tx))
 
 
 class msg_block():
     command = b"block"
 
     def __init__(self, block=None):
         if block is None:
             self.block = CBlock()
         else:
             self.block = block
 
     def deserialize(self, f):
         self.block.deserialize(f)
 
     def serialize(self):
         return self.block.serialize()
 
     def __repr__(self):
         return "msg_block(block={})".format(repr(self.block))
 
 # for cases where a user needs tighter control over what is sent over the wire
 # note that the user must supply the name of the command, and the data
 
 
 class msg_generic():
     def __init__(self, command, data=None):
         self.command = command
         self.data = data
 
     def serialize(self):
         return self.data
 
     def __repr__(self):
         return "msg_generic()"
 
 
 class msg_getaddr():
     command = b"getaddr"
 
     def __init__(self):
         pass
 
     def deserialize(self, f):
         pass
 
     def serialize(self):
         return b""
 
     def __repr__(self):
         return "msg_getaddr()"
 
 
 class msg_ping():
     command = b"ping"
 
     def __init__(self, nonce=0):
         self.nonce = nonce
 
     def deserialize(self, f):
         self.nonce = struct.unpack("<Q", f.read(8))[0]
 
     def serialize(self):
         r = b""
         r += struct.pack("<Q", self.nonce)
         return r
 
     def __repr__(self):
         return "msg_ping(nonce={:08x})".format(self.nonce)
 
 
 class msg_pong():
     command = b"pong"
 
     def __init__(self, nonce=0):
         self.nonce = nonce
 
     def deserialize(self, f):
         self.nonce = struct.unpack("<Q", f.read(8))[0]
 
     def serialize(self):
         r = b""
         r += struct.pack("<Q", self.nonce)
         return r
 
     def __repr__(self):
         return "msg_pong(nonce={:08x})".format(self.nonce)
 
 
 class msg_mempool():
     command = b"mempool"
 
     def __init__(self):
         pass
 
     def deserialize(self, f):
         pass
 
     def serialize(self):
         return b""
 
     def __repr__(self):
         return "msg_mempool()"
 
 
 class msg_sendheaders():
     command = b"sendheaders"
 
     def __init__(self):
         pass
 
     def deserialize(self, f):
         pass
 
     def serialize(self):
         return b""
 
     def __repr__(self):
         return "msg_sendheaders()"
 
 
 # getheaders message has
 # number of entries
 # vector of hashes
 # hash_stop (hash of last desired block header, 0 to get as many as possible)
 class msg_getheaders():
     command = b"getheaders"
 
     def __init__(self):
         self.locator = CBlockLocator()
         self.hashstop = 0
 
     def deserialize(self, f):
         self.locator = CBlockLocator()
         self.locator.deserialize(f)
         self.hashstop = deser_uint256(f)
 
     def serialize(self):
         r = b""
         r += self.locator.serialize()
         r += ser_uint256(self.hashstop)
         return r
 
     def __repr__(self):
         return "msg_getheaders(locator={}, stop={:064x})".format(
             repr(self.locator), self.hashstop)
 
 
 # headers message has
 # <count> <vector of block headers>
 class msg_headers():
     command = b"headers"
 
     def __init__(self, headers=None):
         self.headers = headers if headers is not None else []
 
     def deserialize(self, f):
         # comment in bitcoind indicates these should be deserialized as blocks
         blocks = deser_vector(f, CBlock)
         for x in blocks:
             self.headers.append(CBlockHeader(x))
 
     def serialize(self):
         blocks = [CBlock(x) for x in self.headers]
         return ser_vector(blocks)
 
     def __repr__(self):
         return "msg_headers(headers={})".format(repr(self.headers))
 
 
 class msg_reject():
     command = b"reject"
     REJECT_MALFORMED = 1
 
     def __init__(self):
         self.message = b""
         self.code = 0
         self.reason = b""
         self.data = 0
 
     def deserialize(self, f):
         self.message = deser_string(f)
         self.code = struct.unpack("<B", f.read(1))[0]
         self.reason = deser_string(f)
         if (self.code != self.REJECT_MALFORMED and
                 (self.message == b"block" or self.message == b"tx")):
             self.data = deser_uint256(f)
 
     def serialize(self):
         r = ser_string(self.message)
         r += struct.pack("<B", self.code)
         r += ser_string(self.reason)
         if (self.code != self.REJECT_MALFORMED and
                 (self.message == b"block" or self.message == b"tx")):
             r += ser_uint256(self.data)
         return r
 
     def __repr__(self):
         return "msg_reject: {} {} {} [{:064x}]".format(
             self.message, self.code, self.reason, self.data)
 
 
 class msg_feefilter():
     command = b"feefilter"
 
     def __init__(self, feerate=0):
         self.feerate = feerate
 
     def deserialize(self, f):
         self.feerate = struct.unpack("<Q", f.read(8))[0]
 
     def serialize(self):
         r = b""
         r += struct.pack("<Q", self.feerate)
         return r
 
     def __repr__(self):
         return "msg_feefilter(feerate={:08x})".format(self.feerate)
 
 
 class msg_sendcmpct():
     command = b"sendcmpct"
 
     def __init__(self):
         self.announce = False
         self.version = 1
 
     def deserialize(self, f):
         self.announce = struct.unpack("<?", f.read(1))[0]
         self.version = struct.unpack("<Q", f.read(8))[0]
 
     def serialize(self):
         r = b""
         r += struct.pack("<?", self.announce)
         r += struct.pack("<Q", self.version)
         return r
 
     def __repr__(self):
         return "msg_sendcmpct(announce={}, version={})".format(
             self.announce, self.version)
 
 
 class msg_cmpctblock():
     command = b"cmpctblock"
 
     def __init__(self, header_and_shortids=None):
         self.header_and_shortids = header_and_shortids
 
     def deserialize(self, f):
         self.header_and_shortids = P2PHeaderAndShortIDs()
         self.header_and_shortids.deserialize(f)
 
     def serialize(self):
         r = b""
         r += self.header_and_shortids.serialize()
         return r
 
     def __repr__(self):
         return "msg_cmpctblock(HeaderAndShortIDs={})".format(
             repr(self.header_and_shortids))
 
 
 class msg_getblocktxn():
     command = b"getblocktxn"
 
     def __init__(self):
         self.block_txn_request = None
 
     def deserialize(self, f):
         self.block_txn_request = BlockTransactionsRequest()
         self.block_txn_request.deserialize(f)
 
     def serialize(self):
         r = b""
         r += self.block_txn_request.serialize()
         return r
 
     def __repr__(self):
         return "msg_getblocktxn(block_txn_request={})".format(
             repr(self.block_txn_request))
 
 
 class msg_blocktxn():
     command = b"blocktxn"
 
     def __init__(self):
         self.block_transactions = BlockTransactions()
 
     def deserialize(self, f):
         self.block_transactions.deserialize(f)
 
     def serialize(self):
         r = b""
         r += self.block_transactions.serialize()
         return r
 
     def __repr__(self):
         return "msg_blocktxn(block_transactions={})".format(
             repr(self.block_transactions))
diff --git a/test/functional/test_framework/mininode.py b/test/functional/test_framework/mininode.py
index 88f1ec2e23..ab2083919c 100755
--- a/test/functional/test_framework/mininode.py
+++ b/test/functional/test_framework/mininode.py
@@ -1,524 +1,687 @@
 #!/usr/bin/env python3
 # Copyright (c) 2010 ArtForz -- public domain half-a-node
 # Copyright (c) 2012 Jeff Garzik
 # Copyright (c) 2010-2016 The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 """Bitcoin P2P network half-a-node.
 
 This python code was modified from ArtForz' public domain half-a-node, as
 found in the mini-node branch of http://github.com/jgarzik/pynode.
 
 P2PConnection: A low-level connection object to a node's P2P interface
-P2PInterface: A high-level interface object for communicating to a node over P2P"""
+P2PInterface: A high-level interface object for communicating to a node over P2P
+P2PDataStore: A p2p interface class that keeps a store of transactions and blocks
+              and can respond correctly to getdata and getheaders messages"""
 import asyncore
 from collections import defaultdict
 from io import BytesIO
 import logging
 import socket
 import struct
 import sys
 import threading
 
 from test_framework.messages import (
     MIN_VERSION_SUPPORTED,
     msg_addr,
     msg_block,
+    MSG_BLOCK,
     msg_blocktxn,
     msg_cmpctblock,
     msg_feefilter,
     msg_getaddr,
     msg_getblocks,
     msg_getblocktxn,
     msg_getdata,
     msg_getheaders,
     msg_headers,
     msg_inv,
     msg_mempool,
     msg_ping,
     msg_pong,
     msg_reject,
     msg_sendcmpct,
     msg_sendheaders,
     msg_tx,
+    MSG_TX,
+    MSG_TYPE_MASK,
     msg_verack,
     msg_version,
     NODE_NETWORK,
     READ_BUFFER_SIZE,
     sha256,
 )
 from test_framework.util import wait_until
 
 logger = logging.getLogger("TestFramework.mininode")
 
 MESSAGEMAP = {
     b"addr": msg_addr,
     b"block": msg_block,
     b"blocktxn": msg_blocktxn,
     b"cmpctblock": msg_cmpctblock,
     b"feefilter": msg_feefilter,
     b"getaddr": msg_getaddr,
     b"getblocks": msg_getblocks,
     b"getblocktxn": msg_getblocktxn,
     b"getdata": msg_getdata,
     b"getheaders": msg_getheaders,
     b"headers": msg_headers,
     b"inv": msg_inv,
     b"mempool": msg_mempool,
     b"ping": msg_ping,
     b"pong": msg_pong,
     b"reject": msg_reject,
     b"sendcmpct": msg_sendcmpct,
     b"sendheaders": msg_sendheaders,
     b"tx": msg_tx,
     b"verack": msg_verack,
     b"version": msg_version,
 }
 
 MAGIC_BYTES = {
     "mainnet": b"\xe3\xe1\xf3\xe8",
     "testnet3": b"\xf4\xe5\xf3\xf4",
     "regtest": b"\xda\xb5\xbf\xfa",
 }
 
 
 class P2PConnection(asyncore.dispatcher):
     """A low-level connection object to a node's P2P interface.
 
     This class is responsible for:
 
     - opening and closing the TCP connection to the node
     - reading bytes from and writing bytes to the socket
     - deserializing and serializing the P2P message header
     - logging messages as they are sent and received
 
     This class contains no logic for handing the P2P message payloads. It must be
     sub-classed and the on_message() callback overridden."""
 
     def __init__(self):
         # All P2PConnections must be created before starting the NetworkThread.
         # assert that the network thread is not running.
         assert not network_thread_running()
 
         super().__init__(map=mininode_socket_map)
 
     def peer_connect(self, dstaddr, dstport, net="regtest"):
         self.dstaddr = dstaddr
         self.dstport = dstport
         self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
         self.socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
         self.sendbuf = b""
         self.recvbuf = b""
         self.state = "connecting"
         self.network = net
         self.disconnect = False
 
-        logger.info('Connecting to Bitcoin Node: {}:{}'.format(
+        logger.debug('Connecting to Bitcoin Node: {}:{}'.format(
             self.dstaddr, self.dstport))
 
         try:
             self.connect((dstaddr, dstport))
         except:
             self.handle_close()
 
     def peer_disconnect(self):
         # Connection could have already been closed by other end.
         if self.state == "connected":
             self.disconnect_node()
 
     # Connection and disconnection methods
 
     def handle_connect(self):
         """asyncore callback when a connection is opened."""
         if self.state != "connected":
             logger.debug("Connected & Listening: {}:{}".format(
                 self.dstaddr, self.dstport))
             self.state = "connected"
             self.on_open()
 
     def handle_close(self):
         """asyncore callback when a connection is closed."""
         logger.debug("Closing connection to: {}:{}".format(
             self.dstaddr, self.dstport))
         self.state = "closed"
         self.recvbuf = b""
         self.sendbuf = b""
         try:
             self.close()
         except:
             pass
         self.on_close()
 
     def disconnect_node(self):
         """Disconnect the p2p connection.
 
         Called by the test logic thread. Causes the p2p connection
         to be disconnected on the next iteration of the asyncore loop."""
         self.disconnect = True
 
     # Socket read methods
 
     def handle_read(self):
         """asyncore callback when data is read from the socket."""
         with mininode_lock:
             t = self.recv(READ_BUFFER_SIZE)
             if len(t) > 0:
                 self.recvbuf += t
 
         while True:
             msg = self._on_data()
             if msg == None:
                 break
             self.on_message(msg)
 
     def _on_data(self):
         """Try to read P2P messages from the recv buffer.
 
         This method reads data from the buffer in a loop. It deserializes,
         parses and verifies the P2P header, then passes the P2P payload to
         the on_message callback for processing."""
         try:
             with mininode_lock:
                 if len(self.recvbuf) < 4:
                     return None
                 if self.recvbuf[:4] != MAGIC_BYTES[self.network]:
                     raise ValueError(
                         "got garbage {}".format(repr(self.recvbuf)))
                 if len(self.recvbuf) < 4 + 12 + 4 + 4:
                     return
                 command = self.recvbuf[4:4+12].split(b"\x00", 1)[0]
                 msglen = struct.unpack("<i", self.recvbuf[4+12:4+12+4])[0]
                 checksum = self.recvbuf[4+12+4:4+12+4+4]
                 if len(self.recvbuf) < 4 + 12 + 4 + 4 + msglen:
                     return
                 msg = self.recvbuf[4+12+4+4:4+12+4+4+msglen]
                 h = sha256(sha256(msg))
                 if checksum != h[:4]:
                     raise ValueError("got bad checksum " + repr(self.recvbuf))
                 self.recvbuf = self.recvbuf[4+12+4+4+msglen:]
                 if command not in MESSAGEMAP:
                     raise ValueError("Received unknown command from {}:{}: '{}' {}".format(
                         self.dstaddr, self.dstport, command, repr(msg)))
                 f = BytesIO(msg)
                 m = MESSAGEMAP[command]()
                 m.deserialize(f)
                 self._log_message("receive", m)
                 return m
         except Exception as e:
             logger.exception('Error reading message:', repr(e))
             raise
 
     def on_message(self, message):
         """Callback for processing a P2P payload. Must be overridden by derived class."""
         raise NotImplementedError
 
     # Socket write methods
 
     def writable(self):
         """asyncore method to determine whether the handle_write() callback should be called on the next loop."""
         with mininode_lock:
             pre_connection = self.state == "connecting"
             length = len(self.sendbuf)
         return (length > 0 or pre_connection)
 
     def handle_write(self):
         """asyncore callback when data should be written to the socket."""
         with mininode_lock:
             # asyncore does not expose socket connection, only the first read/write
             # event, thus we must check connection manually here to know when we
             # actually connect
             if self.state == "connecting":
                 self.handle_connect()
             if not self.writable():
                 return
 
             try:
                 sent = self.send(self.sendbuf)
             except:
                 self.handle_close()
                 return
             self.sendbuf = self.sendbuf[sent:]
 
     def format_message(self, message):
         command = message.command
         data = message.serialize()
         tmsg = MAGIC_BYTES[self.network]
         tmsg += command
         tmsg += b"\x00" * (12 - len(command))
         tmsg += struct.pack("<I", len(data))
         th = sha256(data)
         h = sha256(th)
         tmsg += h[:4]
         tmsg += data
         return tmsg
 
     def send_message(self, message, pushbuf=False):
         """Send a P2P message over the socket.
 
         This method takes a P2P payload, builds the P2P header and adds
         the message to the send buffer to be sent over the socket."""
         if self.state != "connected" and not pushbuf:
             raise IOError('Not connected, no pushbuf')
         self._log_message("send", message)
         tmsg = self.format_message(message)
         self.send_raw_message(tmsg, pushbuf)
 
     def send_raw_message(self, tmsg, pushbuf=False):
         """Send any raw message over the socket.
 
         This method adds a raw message to the send buffer to be sent over the
         socket."""
         if self.state != "connected" and not pushbuf:
             raise IOError('Not connected, no pushbuf')
         with mininode_lock:
             if (len(self.sendbuf) == 0 and not pushbuf):
                 try:
                     sent = self.send(tmsg)
                     self.sendbuf = tmsg[sent:]
                 except BlockingIOError:
                     self.sendbuf = tmsg
             else:
                 self.sendbuf += tmsg
 
     # Class utility methods
 
     def _log_message(self, direction, msg):
         """Logs a message being sent or received over the connection."""
         if direction == "send":
             log_message = "Send message to "
         elif direction == "receive":
             log_message = "Received message from "
         log_message += "{}:{}: {}".format(
             self.dstaddr, self.dstport, repr(msg)[:500])
         if len(log_message) > 500:
             log_message += "... (msg truncated)"
         logger.debug(log_message)
 
 
 class P2PInterface(P2PConnection):
     """A high-level P2P interface class for communicating with a Bitcoin Cash node.
 
     This class provides high-level callbacks for processing P2P message
     payloads, as well as convenience methods for interacting with the
     node over P2P.
 
     Individual testcases should subclass this and override the on_* methods
     if they want to alter message handling behaviour."""
 
     def __init__(self):
         super().__init__()
 
         # Track number of messages of each type received and the most recent
         # message of each type
         self.message_count = defaultdict(int)
         self.last_message = {}
 
         # A count of the number of ping messages we've sent to the node
         self.ping_counter = 1
 
         # The network services received from the peer
         self.nServices = 0
 
     def peer_connect(self, *args, services=NODE_NETWORK, send_version=True, **kwargs):
         super().peer_connect(*args, **kwargs)
 
         if send_version:
             # Send a version msg
             vt = msg_version()
             vt.nServices = services
             vt.addrTo.ip = self.dstaddr
             vt.addrTo.port = self.dstport
             vt.addrFrom.ip = "0.0.0.0"
             vt.addrFrom.port = 0
             self.send_message(vt, True)
 
     # Message receiving methods
 
     def on_message(self, message):
         """Receive message and dispatch message to appropriate callback.
 
         We keep a count of how many of each message type has been received
         and the most recent message of each type."""
         with mininode_lock:
             try:
                 command = message.command.decode('ascii')
                 self.message_count[command] += 1
                 self.last_message[command] = message
                 getattr(self, 'on_' + command)(message)
             except:
                 print("ERROR delivering {} ({})".format(
                     repr(message), sys.exc_info()[0]))
                 raise
 
     # Callback methods. Can be overridden by subclasses in individual test
     # cases to provide custom message handling behaviour.
 
     def on_open(self):
         pass
 
     def on_close(self):
         pass
 
     def on_addr(self, message): pass
 
     def on_block(self, message): pass
 
     def on_blocktxn(self, message): pass
 
     def on_cmpctblock(self, message): pass
 
     def on_feefilter(self, message): pass
 
     def on_getaddr(self, message): pass
 
     def on_getblocks(self, message): pass
 
     def on_getblocktxn(self, message): pass
 
     def on_getdata(self, message): pass
 
     def on_getheaders(self, message): pass
 
     def on_headers(self, message): pass
 
     def on_mempool(self, message): pass
 
     def on_pong(self, message): pass
 
     def on_reject(self, message): pass
 
     def on_sendcmpct(self, message): pass
 
     def on_sendheaders(self, message): pass
 
     def on_tx(self, message): pass
 
     def on_inv(self, message):
         want = msg_getdata()
         for i in message.inv:
             if i.type != 0:
                 want.inv.append(i)
         if len(want.inv):
             self.send_message(want)
 
     def on_ping(self, message):
         self.send_message(msg_pong(message.nonce))
 
     def on_verack(self, message):
         self.verack_received = True
 
     def on_version(self, message):
         assert message.nVersion >= MIN_VERSION_SUPPORTED, "Version {} received. Test framework only supports versions greater than {}".format(
             message.nVersion, MIN_VERSION_SUPPORTED)
         self.send_message(msg_verack())
         self.nServices = message.nServices
 
     # Connection helper methods
 
     def wait_for_disconnect(self, timeout=60):
         def test_function(): return self.state != "connected"
         wait_until(test_function, timeout=timeout, lock=mininode_lock)
 
     # Message receiving helper methods
 
     def wait_for_block(self, blockhash, timeout=60):
         def test_function(): return self.last_message.get(
             "block") and self.last_message["block"].block.rehash() == blockhash
         wait_until(test_function, timeout=timeout, lock=mininode_lock)
 
     def wait_for_getdata(self, timeout=60):
+        """Waits for a getdata message.
+
+        Receiving any getdata message will satisfy the predicate. the last_message["getdata"]
+        value must be explicitly cleared before calling this method, or this will return
+        immediately with success. TODO: change this method to take a hash value and only
+        return true if the correct block/tx has been requested."""
         def test_function(): return self.last_message.get("getdata")
         wait_until(test_function, timeout=timeout, lock=mininode_lock)
 
     def wait_for_getheaders(self, timeout=60):
+        """Waits for a getheaders message.
+
+        Receiving any getheaders message will satisfy the predicate. the last_message["getheaders"]
+        value must be explicitly cleared before calling this method, or this will return
+        immediately with success. TODO: change this method to take a hash value and only
+        return true if the correct block header has been requested."""
         def test_function(): return self.last_message.get("getheaders")
         wait_until(test_function, timeout=timeout, lock=mininode_lock)
 
     def wait_for_inv(self, expected_inv, timeout=60):
         """Waits for an INV message and checks that the first inv object in the message was as expected."""
         if len(expected_inv) > 1:
             raise NotImplementedError(
                 "wait_for_inv() will only verify the first inv object")
 
         def test_function(): return self.last_message.get("inv") and \
             self.last_message["inv"].inv[0].type == expected_inv[0].type and \
             self.last_message["inv"].inv[0].hash == expected_inv[0].hash
         wait_until(test_function, timeout=timeout, lock=mininode_lock)
 
     def wait_for_verack(self, timeout=60):
         def test_function(): return self.message_count["verack"]
         wait_until(test_function, timeout=timeout, lock=mininode_lock)
 
     # Message sending helper functions
 
     def send_and_ping(self, message):
         self.send_message(message)
         self.sync_with_ping()
 
     # Sync up with the node
     def sync_with_ping(self, timeout=60):
         self.send_message(msg_ping(nonce=self.ping_counter))
 
         def test_function():
             if not self.last_message.get("pong"):
                 return False
             return self.last_message["pong"].nonce == self.ping_counter
         wait_until(test_function, timeout=timeout, lock=mininode_lock)
         self.ping_counter += 1
 
 
 # Keep our own socket map for asyncore, so that we can track disconnects
 # ourselves (to workaround an issue with closing an asyncore socket when
 # using select)
 mininode_socket_map = dict()
 
 # One lock for synchronizing all data access between the networking thread (see
 # NetworkThread below) and the thread running the test logic.  For simplicity,
 # P2PConnection acquires this lock whenever delivering a message to a P2PInterface,
 # and whenever adding anything to the send buffer (in send_message()).  This
 # lock should be acquired in the thread running the test logic to synchronize
 # access to any data shared with the P2PInterface or P2PConnection.
 mininode_lock = threading.RLock()
 
 
 class NetworkThread(threading.Thread):
     def __init__(self):
         super().__init__(name="NetworkThread")
 
     def run(self):
         while mininode_socket_map:
             # We check for whether to disconnect outside of the asyncore
             # loop to workaround the behavior of asyncore when using
             # select
             disconnected = []
             for fd, obj in mininode_socket_map.items():
                 if obj.disconnect:
                     disconnected.append(obj)
             [obj.handle_close() for obj in disconnected]
             asyncore.loop(0.1, use_poll=True, map=mininode_socket_map, count=1)
         logger.debug("Network thread closing")
 
 
 def network_thread_start():
     """Start the network thread."""
     # Only one network thread may run at a time
     assert not network_thread_running()
 
     NetworkThread().start()
 
 
 def network_thread_running():
     """Return whether the network thread is running."""
     return any([thread.name == "NetworkThread" for thread in threading.enumerate()])
 
 
 def network_thread_join(timeout=10):
     """Wait timeout seconds for the network thread to terminate.
 
     Throw if the network thread doesn't terminate in timeout seconds."""
     network_threads = [
         thread for thread in threading.enumerate() if thread.name == "NetworkThread"]
     assert len(network_threads) <= 1
     for thread in network_threads:
         thread.join(timeout)
         assert not thread.is_alive()
+
+
+class P2PDataStore(P2PInterface):
+    """A P2P data store class.
+
+    Keeps a block and transaction store and responds correctly to getdata and getheaders requests."""
+
+    def __init__(self):
+        super().__init__()
+        self.reject_code_received = None
+        self.reject_reason_received = None
+        # store of blocks. key is block hash, value is a CBlock object
+        self.block_store = {}
+        self.last_block_hash = ''
+        # store of txs. key is txid, value is a CTransaction object
+        self.tx_store = {}
+        self.getdata_requests = []
+
+    def on_getdata(self, message):
+        """Check for the tx/block in our stores and if found, reply with an inv message."""
+        for inv in message.inv:
+            self.getdata_requests.append(inv.hash)
+            if (inv.type & MSG_TYPE_MASK) == MSG_TX and inv.hash in self.tx_store.keys():
+                self.send_message(msg_tx(self.tx_store[inv.hash]))
+            elif (inv.type & MSG_TYPE_MASK) == MSG_BLOCK and inv.hash in self.block_store.keys():
+                self.send_message(msg_block(self.block_store[inv.hash]))
+            else:
+                logger.debug(
+                    'getdata message type {} received.'.format(hex(inv.type)))
+
+    def on_getheaders(self, message):
+        """Search back through our block store for the locator, and reply with a headers message if found."""
+
+        locator, hash_stop = message.locator, message.hashstop
+
+        # Assume that the most recent block added is the tip
+        if not self.block_store:
+            return
+
+        headers_list = [self.block_store[self.last_block_hash]]
+        maxheaders = 2000
+        while headers_list[-1].sha256 not in locator.vHave:
+            # Walk back through the block store, adding headers to headers_list
+            # as we go.
+            prev_block_hash = headers_list[-1].hashPrevBlock
+            if prev_block_hash in self.block_store:
+                prev_block_header = self.block_store[prev_block_hash]
+                headers_list.append(prev_block_header)
+                if prev_block_header.sha256 == hash_stop:
+                    # if this is the hashstop header, stop here
+                    break
+            else:
+                logger.debug('block hash {} not found in block store'.format(
+                    hex(prev_block_hash)))
+                break
+
+        # Truncate the list if there are too many headers
+        headers_list = headers_list[:-maxheaders - 1:-1]
+        response = msg_headers(headers_list)
+
+        if response is not None:
+            self.send_message(response)
+
+    def on_reject(self, message):
+        """Store reject reason and code for testing."""
+        self.reject_code_received = message.code
+        self.reject_reason_received = message.reason
+
+    def send_blocks_and_test(self, blocks, rpc, success=True, request_block=True, reject_code=None, reject_reason=None, timeout=60):
+        """Send blocks to test node and test whether the tip advances.
+
+         - add all blocks to our block_store
+         - send a headers message for the final block
+         - the on_getheaders handler will ensure that any getheaders are responded to
+         - if request_block is True: wait for getdata for each of the blocks. The on_getdata handler will
+           ensure that any getdata messages are responded to
+         - if success is True: assert that the node's tip advances to the most recent block
+         - if success is False: assert that the node's tip doesn't advance
+         - if reject_code and reject_reason are set: assert that the correct reject message is received"""
+
+        with mininode_lock:
+            self.reject_code_received = None
+            self.reject_reason_received = None
+
+            for block in blocks:
+                self.block_store[block.sha256] = block
+                self.last_block_hash = block.sha256
+
+        self.send_message(msg_headers([blocks[-1]]))
+
+        if request_block:
+            wait_until(
+                lambda: blocks[-1].sha256 in self.getdata_requests, timeout=timeout, lock=mininode_lock)
+
+        if success:
+            wait_until(lambda: rpc.getbestblockhash() ==
+                       blocks[-1].hash, timeout=timeout)
+        else:
+            assert rpc.getbestblockhash() != blocks[-1].hash
+
+        if reject_code is not None:
+            wait_until(lambda: self.reject_code_received ==
+                       reject_code, lock=mininode_lock)
+        if reject_reason is not None:
+            wait_until(lambda: self.reject_reason_received ==
+                       reject_reason, lock=mininode_lock)
+
+    def send_txs_and_test(self, txs, rpc, success=True, reject_code=None, reject_reason=None):
+        """Send txs to test node and test whether they're accepted to the mempool.
+
+         - add all txs to our tx_store
+         - send tx messages for all txs
+         - if success is True: assert that the tx is accepted to the mempool
+         - if success is False: assert that the tx is not accepted to the mempool
+         - if reject_code and reject_reason are set: assert that the correct reject message is received."""
+
+        with mininode_lock:
+            self.reject_code_received = None
+            self.reject_reason_received = None
+
+            for tx in txs:
+                self.tx_store[tx.sha256] = tx
+
+        for tx in txs:
+            self.send_message(msg_tx(tx))
+
+        self.sync_with_ping()
+
+        raw_mempool = rpc.getrawmempool()
+        if success:
+            # Check that all txs are now in the mempool
+            for tx in txs:
+                assert tx.hash in raw_mempool, "{} not found in mempool".format(
+                    tx.hash)
+        else:
+            # Check that none of the txs are now in the mempool
+            for tx in txs:
+                assert tx.hash not in raw_mempool, "{} tx found in mempool".format(
+                    tx.hash)
+
+        if reject_code is not None:
+            wait_until(lambda: self.reject_code_received ==
+                       reject_code, lock=mininode_lock)
+        if reject_reason is not None:
+            wait_until(lambda: self.reject_reason_received ==
+                       reject_reason, lock=mininode_lock)