Add script manipulation tools for use in mininode testing framework

script.py is modified from the code in python-bitcoinlib, and provides tools
for manipulating and creating CScript objects.

bignum.py is a dependency for script.py

script_test.py is an example test that uses the script tools for running a test
that compares the behavior of two nodes, in a comptool- style test, for each of
the test cases in the bitcoin unit test script files, script_valid.json and
script_invalid.json.  (This test is very slow to run, but is a proof of concept
for how we can write tests to compare consensus-critical behavior between
different versions of bitcoind.)

bipdersig-p2p.py is another example test in the comptool framework, which tests
deployment of BIP DERSIG for a single node.  It uses the script.py tools for
manipulating signatures to be non-DER compliant.

qa/rpc-tests/bignum.py

@@ -0,0 +1,102 @@
+#
+#
+# bignum.py
+#
+# This file is copied from python-bitcoinlib.
+#
+# Distributed under the MIT/X11 software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+#
+
+"""Bignum routines"""
+
+from __future__ import absolute_import, division, print_function, unicode_literals
+
+import struct
+
+
+# generic big endian MPI format
+
+def bn_bytes(v, have_ext=False):
+    ext = 0
+    if have_ext:
+        ext = 1
+    return ((v.bit_length()+7)//8) + ext
+
+def bn2bin(v):
+    s = bytearray()
+    i = bn_bytes(v)
+    while i > 0:
+        s.append((v >> ((i-1) * 8)) & 0xff)
+        i -= 1
+    return s
+
+def bin2bn(s):
+    l = 0
+    for ch in s:
+        l = (l << 8) | ch
+    return l
+
+def bn2mpi(v):
+    have_ext = False
+    if v.bit_length() > 0:
+        have_ext = (v.bit_length() & 0x07) == 0
+
+    neg = False
+    if v < 0:
+        neg = True
+        v = -v
+
+    s = struct.pack(b">I", bn_bytes(v, have_ext))
+    ext = bytearray()
+    if have_ext:
+        ext.append(0)
+    v_bin = bn2bin(v)
+    if neg:
+        if have_ext:
+            ext[0] |= 0x80
+        else:
+            v_bin[0] |= 0x80
+    return s + ext + v_bin
+
+def mpi2bn(s):
+    if len(s) < 4:
+        return None
+    s_size = bytes(s[:4])
+    v_len = struct.unpack(b">I", s_size)[0]
+    if len(s) != (v_len + 4):
+        return None
+    if v_len == 0:
+        return 0
+
+    v_str = bytearray(s[4:])
+    neg = False
+    i = v_str[0]
+    if i & 0x80:
+        neg = True
+        i &= ~0x80
+        v_str[0] = i
+
+    v = bin2bn(v_str)
+
+    if neg:
+        return -v
+    return v
+
+# bitcoin-specific little endian format, with implicit size
+def mpi2vch(s):
+    r = s[4:]           # strip size
+    r = r[::-1]         # reverse string, converting BE->LE
+    return r
+
+def bn2vch(v):
+    return bytes(mpi2vch(bn2mpi(v)))
+
+def vch2mpi(s):
+    r = struct.pack(b">I", len(s))   # size
+    r += s[::-1]            # reverse string, converting LE->BE
+    return r
+
+def vch2bn(s):
+    return mpi2bn(vch2mpi(s))
+

qa/rpc-tests/bipdersig-p2p.py

@@ -0,0 +1,183 @@
+#!/usr/bin/env python2
+#
+# Distributed under the MIT/X11 software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+#
+
+from test_framework import ComparisonTestFramework
+from util import *
+from mininode import CTransaction, NetworkThread
+from blocktools import create_coinbase, create_block
+from binascii import hexlify, unhexlify
+import cStringIO
+from comptool import TestInstance, TestManager
+from script import CScript
+import time
+
+# A canonical signature consists of: 
+# <30> <total len> <02> <len R> <R> <02> <len S> <S> <hashtype>
+def unDERify(tx):
+    '''
+    Make the signature in vin 0 of a tx non-DER-compliant,
+    by adding padding after the S-value.
+    '''
+    scriptSig = CScript(tx.vin[0].scriptSig)
+    newscript = []
+    for i in scriptSig:
+        if (len(newscript) == 0):
+            newscript.append(i[0:-1] + '\0' + i[-1])
+        else:
+            newscript.append(i)
+    tx.vin[0].scriptSig = CScript(newscript)
+    
+'''
+This test is meant to exercise BIP66 (DER SIG).
+Connect to a single node.
+Mine 2 (version 2) blocks (save the coinbases for later).
+Generate 98 more version 2 blocks, verify the node accepts.
+Mine 749 version 3 blocks, verify the node accepts.
+Check that the new DERSIG rules are not enforced on the 750th version 3 block.
+Check that the new DERSIG rules are enforced on the 751st version 3 block.
+Mine 199 new version blocks.
+Mine 1 old-version block.
+Mine 1 new version block.
+Mine 1 old version block, see that the node rejects.
+'''
+            
+class BIP66Test(ComparisonTestFramework):
+
+    def __init__(self):
+        self.num_nodes = 1
+
+    def setup_network(self):
+        # Must set the blockversion for this test
+        self.nodes = start_nodes(1, self.options.tmpdir, 
+                                 extra_args=[['-debug', '-whitelist=127.0.0.1', '-blockversion=2']],
+                                 binary=[self.options.testbinary])
+
+    def run_test(self):
+        test = TestManager(self, self.options.tmpdir)
+        test.add_all_connections(self.nodes)
+        NetworkThread().start() # Start up network handling in another thread
+        test.run()
+
+    def create_transaction(self, node, coinbase, to_address, amount):
+        from_txid = node.getblock(coinbase)['tx'][0]
+        inputs = [{ "txid" : from_txid, "vout" : 0}]
+        outputs = { to_address : amount }
+        rawtx = node.createrawtransaction(inputs, outputs)
+        signresult = node.signrawtransaction(rawtx)
+        tx = CTransaction()
+        f = cStringIO.StringIO(unhexlify(signresult['hex']))
+        tx.deserialize(f)
+        return tx
+
+    def get_tests(self):
+
+        self.coinbase_blocks = self.nodes[0].generate(2)
+        self.tip = int ("0x" + self.nodes[0].getbestblockhash() + "L", 0)
+        self.nodeaddress = self.nodes[0].getnewaddress()
+        self.last_block_time = time.time()
+
+        ''' 98 more version 2 blocks '''
+        test_blocks = []
+        for i in xrange(98):
+            block = create_block(self.tip, create_coinbase(2), self.last_block_time + 1)
+            block.nVersion = 2
+            block.rehash()
+            block.solve()
+            test_blocks.append([block, True])
+            self.last_block_time += 1
+            self.tip = block.sha256
+        yield TestInstance(test_blocks, sync_every_block=False)
+
+        ''' Mine 749 version 3 blocks '''
+        test_blocks = []
+        for i in xrange(749):
+            block = create_block(self.tip, create_coinbase(2), self.last_block_time + 1)
+            block.nVersion = 3
+            block.rehash()
+            block.solve()
+            test_blocks.append([block, True])
+            self.last_block_time += 1
+            self.tip = block.sha256
+        yield TestInstance(test_blocks, sync_every_block=False)
+
+        ''' 
+        Check that the new DERSIG rules are not enforced in the 750th
+        version 3 block.
+        '''
+        spendtx = self.create_transaction(self.nodes[0],
+                self.coinbase_blocks[0], self.nodeaddress, 1.0)
+        unDERify(spendtx)
+        spendtx.rehash()
+
+        block = create_block(self.tip, create_coinbase(2), self.last_block_time + 1)
+        block.nVersion = 3
+        block.vtx.append(spendtx)
+        block.hashMerkleRoot = block.calc_merkle_root()
+        block.rehash()
+        block.solve()
+
+        self.last_block_time += 1
+        self.tip = block.sha256
+        yield TestInstance([[block, True]])
+
+        ''' 
+        Check that the new DERSIG rules are enforced in the 751st version 3
+        block.
+        '''
+        spendtx = self.create_transaction(self.nodes[0],
+                self.coinbase_blocks[1], self.nodeaddress, 1.0)
+        unDERify(spendtx)
+        spendtx.rehash()
+
+        block = create_block(self.tip, create_coinbase(1), self.last_block_time + 1)
+        block.nVersion = 3
+        block.vtx.append(spendtx)
+        block.hashMerkleRoot = block.calc_merkle_root()
+        block.rehash()
+        block.solve()
+        self.last_block_time += 1
+        yield TestInstance([[block, False]])
+
+        ''' Mine 199 new version blocks on last valid tip '''
+        test_blocks = []
+        for i in xrange(199):
+            block = create_block(self.tip, create_coinbase(1), self.last_block_time + 1)
+            block.nVersion = 3
+            block.rehash()
+            block.solve()
+            test_blocks.append([block, True])
+            self.last_block_time += 1
+            self.tip = block.sha256
+        yield TestInstance(test_blocks, sync_every_block=False)
+
+        ''' Mine 1 old version block '''
+        block = create_block(self.tip, create_coinbase(1), self.last_block_time + 1)
+        block.nVersion = 2
+        block.rehash()
+        block.solve()
+        self.last_block_time += 1
+        self.tip = block.sha256
+        yield TestInstance([[block, True]])
+
+        ''' Mine 1 new version block '''
+        block = create_block(self.tip, create_coinbase(1), self.last_block_time + 1)
+        block.nVersion = 3
+        block.rehash()
+        block.solve()
+        self.last_block_time += 1
+        self.tip = block.sha256
+        yield TestInstance([[block, True]])
+
+        ''' Mine 1 old version block, should be invalid '''
+        block = create_block(self.tip, create_coinbase(1), self.last_block_time + 1)
+        block.nVersion = 2
+        block.rehash()
+        block.solve()
+        self.last_block_time += 1
+        yield TestInstance([[block, False]])
+
+if __name__ == '__main__':
+    BIP66Test().main()

qa/rpc-tests/script.py

@@ -0,0 +1,896 @@
+#
+# script.py
+#
+# This file is modified from python-bitcoinlib.
+#
+# Distributed under the MIT/X11 software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+#
+
+"""Scripts
+
+Functionality to build scripts, as well as SignatureHash().
+"""
+
+from __future__ import absolute_import, division, print_function, unicode_literals
+
+from mininode import CTransaction, CTxOut, hash256
+
+import sys
+bchr = chr
+bord = ord
+if sys.version > '3':
+    long = int
+    bchr = lambda x: bytes([x])
+    bord = lambda x: x
+
+import copy
+import struct
+
+import bignum
+
+MAX_SCRIPT_SIZE = 10000
+MAX_SCRIPT_ELEMENT_SIZE = 520
+MAX_SCRIPT_OPCODES = 201
+
+OPCODE_NAMES = {}
+
+_opcode_instances = []
+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'' + bchr(len(d)) + d # OP_PUSHDATA
+        elif len(d) <= 0xff:
+            return b'\x4c' + bchr(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(CScriptOp, cls).__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_NOP2 = CScriptOp(0xb1)
+OP_NOP3 = 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)
+
+VALID_OPCODES = {
+    OP_1NEGATE,
+    OP_RESERVED,
+    OP_1,
+    OP_2,
+    OP_3,
+    OP_4,
+    OP_5,
+    OP_6,
+    OP_7,
+    OP_8,
+    OP_9,
+    OP_10,
+    OP_11,
+    OP_12,
+    OP_13,
+    OP_14,
+    OP_15,
+    OP_16,
+
+    OP_NOP,
+    OP_VER,
+    OP_IF,
+    OP_NOTIF,
+    OP_VERIF,
+    OP_VERNOTIF,
+    OP_ELSE,
+    OP_ENDIF,
+    OP_VERIFY,
+    OP_RETURN,
+
+    OP_TOALTSTACK,
+    OP_FROMALTSTACK,
+    OP_2DROP,
+    OP_2DUP,
+    OP_3DUP,
+    OP_2OVER,
+    OP_2ROT,
+    OP_2SWAP,
+    OP_IFDUP,
+    OP_DEPTH,
+    OP_DROP,
+    OP_DUP,
+    OP_NIP,
+    OP_OVER,
+    OP_PICK,
+    OP_ROLL,
+    OP_ROT,
+    OP_SWAP,
+    OP_TUCK,
+
+    OP_CAT,
+    OP_SUBSTR,
+    OP_LEFT,
+    OP_RIGHT,
+    OP_SIZE,
+
+    OP_INVERT,
+    OP_AND,
+    OP_OR,
+    OP_XOR,
+    OP_EQUAL,
+    OP_EQUALVERIFY,
+    OP_RESERVED1,
+    OP_RESERVED2,
+
+    OP_1ADD,
+    OP_1SUB,
+    OP_2MUL,
+    OP_2DIV,
+    OP_NEGATE,
+    OP_ABS,
+    OP_NOT,
+    OP_0NOTEQUAL,
+
+    OP_ADD,
+    OP_SUB,
+    OP_MUL,
+    OP_DIV,
+    OP_MOD,
+    OP_LSHIFT,
+    OP_RSHIFT,
+
+    OP_BOOLAND,
+    OP_BOOLOR,
+    OP_NUMEQUAL,
+    OP_NUMEQUALVERIFY,
+    OP_NUMNOTEQUAL,
+    OP_LESSTHAN,
+    OP_GREATERTHAN,
+    OP_LESSTHANOREQUAL,
+    OP_GREATERTHANOREQUAL,
+    OP_MIN,
+    OP_MAX,
+
+    OP_WITHIN,
+
+    OP_RIPEMD160,
+    OP_SHA1,
+    OP_SHA256,
+    OP_HASH160,
+    OP_HASH256,
+    OP_CODESEPARATOR,
+    OP_CHECKSIG,
+    OP_CHECKSIGVERIFY,
+    OP_CHECKMULTISIG,
+    OP_CHECKMULTISIGVERIFY,
+
+    OP_NOP1,
+    OP_NOP2,
+    OP_NOP3,
+    OP_NOP4,
+    OP_NOP5,
+    OP_NOP6,
+    OP_NOP7,
+    OP_NOP8,
+    OP_NOP9,
+    OP_NOP10,
+
+    OP_SMALLINTEGER,
+    OP_PUBKEYS,
+    OP_PUBKEYHASH,
+    OP_PUBKEY,
+}
+
+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_NOP2 : 'OP_NOP2',
+    OP_NOP3 : 'OP_NOP3',
+    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',
+})
+
+OPCODES_BY_NAME = {
+    '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_NOP2' : OP_NOP2,
+    'OP_NOP3' : OP_NOP3,
+    '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,
+}
+
+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(CScriptTruncatedPushDataError, self).__init__(msg)
+
+# This is used, eg, for blockchain heights in coinbase scripts (bip34)
+class CScriptNum(object):
+    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(chr(absvalue & 0xff))
+            absvalue >>= 8
+        if r[-1] & 0x80:
+            r.append(0x80 if neg else 0)
+        elif neg:
+            r[-1] |= 0x80
+        return bytes(bchr(len(r)) + r)
+
+
+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.
+    """
+    @classmethod
+    def __coerce_instance(cls, other):
+        # Coerce other into bytes
+        if isinstance(other, CScriptOp):
+            other = bchr(other)
+        elif isinstance(other, CScriptNum):
+            if (other.value == 0):
+                other = bchr(CScriptOp(OP_0))
+            else:
+                other = CScriptNum.encode(other)
+        elif isinstance(other, (int, long)):
+            if 0 <= other <= 16:
+                other = bytes(bchr(CScriptOp.encode_op_n(other)))
+            elif other == -1:
+                other = bytes(bchr(OP_1NEGATE))
+            else:
+                other = CScriptOp.encode_op_pushdata(bignum.bn2vch(other))
+        elif isinstance(other, (bytes, bytearray)):
+            other = CScriptOp.encode_op_pushdata(other)
+        return other
+
+    def __add__(self, other):
+        # Do the coercion outside of the try block so that errors in it are
+        # noticed.
+        other = self.__coerce_instance(other)
+
+        try:
+            # bytes.__add__ always returns bytes instances unfortunately
+            return CScript(super(CScript, self).__add__(other))
+        except TypeError:
+            raise TypeError('Can not add a %r instance to a CScript' % other.__class__)
+
+    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(CScript, cls).__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(CScript, cls).__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 = bord(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 = bord(self[i])
+                    i += 1
+
+                elif opcode == OP_PUSHDATA2:
+                    pushdata_type = 'PUSHDATA2'
+                    if i + 1 >= len(self):
+                        raise CScriptInvalidError('PUSHDATA2: missing data length')
+                    datasize = bord(self[i]) + (bord(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 = bord(self[i]) + (bord(self[i+1]) << 8) + (bord(self[i+2]) << 16) + (bord(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):
+        # For Python3 compatibility add b before strings so testcases don't
+        # need to change
+        def _repr(o):
+            if isinstance(o, bytes):
+                return "x('%s')" % binascii.hexlify(o).decode('utf8')
+            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 SignatureHash(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())
+        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()
+    s += struct.pack(b"<I", hashtype)
+
+    hash = hash256(s)
+
+    return (hash, None)

qa/rpc-tests/script_test.py

@@ -0,0 +1,253 @@
+#!/usr/bin/env python2
+#
+# Distributed under the MIT/X11 software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+#
+
+'''
+Test notes:
+This test uses the script_valid and script_invalid tests from the unittest
+framework to do end-to-end testing where we compare that two nodes agree on
+whether blocks containing a given test script are valid.
+
+We generally ignore the script flags associated with each test (since we lack
+the precision to test each script using those flags in this framework), but
+for tests with SCRIPT_VERIFY_P2SH, we can use a block time after the BIP16 
+switchover date to try to test with that flag enabled (and for tests without
+that flag, we use a block time before the switchover date).
+
+NOTE: This test is very slow and may take more than 40 minutes to run.
+'''
+
+from test_framework import ComparisonTestFramework
+from util import *
+from comptool import TestInstance, TestManager
+from mininode import *
+from blocktools import *
+from script import *
+import logging
+import copy
+import json
+
+script_valid_file   = "../../src/test/data/script_valid.json"
+script_invalid_file = "../../src/test/data/script_invalid.json"
+
+# Pass in a set of json files to open. 
+class ScriptTestFile(object):
+
+    def __init__(self, files):
+        self.files = files
+        self.index = -1
+        self.data = []
+
+    def load_files(self):
+        for f in self.files:
+            self.data.extend(json.loads(open(f).read()))
+
+    # Skip over records that are not long enough to be tests
+    def get_records(self):
+        while (self.index < len(self.data)):
+            if len(self.data[self.index]) >= 3:
+                yield self.data[self.index]
+            self.index += 1
+
+
+# Helper for parsing the flags specified in the .json files
+SCRIPT_VERIFY_NONE = 0
+SCRIPT_VERIFY_P2SH = 1 
+SCRIPT_VERIFY_STRICTENC = 1 << 1
+SCRIPT_VERIFY_DERSIG = 1 << 2
+SCRIPT_VERIFY_LOW_S = 1 << 3
+SCRIPT_VERIFY_NULLDUMMY = 1 << 4
+SCRIPT_VERIFY_SIGPUSHONLY = 1 << 5
+SCRIPT_VERIFY_MINIMALDATA = 1 << 6
+SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_NOPS = 1 << 7
+SCRIPT_VERIFY_CLEANSTACK = 1 << 8
+
+flag_map = { 
+    "": SCRIPT_VERIFY_NONE,
+    "NONE": SCRIPT_VERIFY_NONE, 
+    "P2SH": SCRIPT_VERIFY_P2SH,
+    "STRICTENC": SCRIPT_VERIFY_STRICTENC,
+    "DERSIG": SCRIPT_VERIFY_DERSIG,
+    "LOW_S": SCRIPT_VERIFY_LOW_S,
+    "NULLDUMMY": SCRIPT_VERIFY_NULLDUMMY,
+    "SIGPUSHONLY": SCRIPT_VERIFY_SIGPUSHONLY,
+    "MINIMALDATA": SCRIPT_VERIFY_MINIMALDATA,
+    "DISCOURAGE_UPGRADABLE_NOPS": SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_NOPS,
+    "CLEANSTACK": SCRIPT_VERIFY_CLEANSTACK,
+}
+
+def ParseScriptFlags(flag_string):
+    flags = 0
+    for x in flag_string.split(","):
+        if x in flag_map:
+            flags |= flag_map[x]
+        else:
+            print "Error: unrecognized script flag: ", x
+    return flags
+
+'''
+Given a string that is a scriptsig or scriptpubkey from the .json files above,
+convert it to a CScript()
+'''
+# Replicates behavior from core_read.cpp
+def ParseScript(json_script):
+    script = json_script.split(" ")
+    parsed_script = CScript()
+    for x in script:
+        if len(x) == 0:
+            # Empty string, ignore.
+            pass
+        elif x.isdigit() or (len(x) >= 1 and x[0] == "-" and x[1:].isdigit()):
+            # Number
+            n = int(x, 0)
+            if (n == -1) or (n >= 1 and n <= 16):
+                parsed_script = CScript(bytes(parsed_script) + bytes(CScript([n])))
+            else:
+                parsed_script += CScriptNum(int(x, 0))
+        elif x.startswith("0x"):
+            # Raw hex data, inserted NOT pushed onto stack:
+            for i in xrange(2, len(x), 2):
+                parsed_script = CScript(bytes(parsed_script) + bytes(chr(int(x[i:i+2],16))))
+        elif x.startswith("'") and x.endswith("'") and len(x) >= 2:
+            # Single-quoted string, pushed as data.
+            parsed_script += CScript([x[1:-1]])
+        else:
+            # opcode, e.g. OP_ADD or ADD:
+            tryopname = "OP_" + x
+            if tryopname in OPCODES_BY_NAME:
+                parsed_script += CScriptOp(OPCODES_BY_NAME["OP_" + x])
+            else:
+                print "ParseScript: error parsing '%s'" % x
+                return ""
+    return parsed_script
+            
+class TestBuilder(object):
+    def create_credit_tx(self, scriptPubKey):
+        # self.tx1 is a coinbase transaction, modeled after the one created by script_tests.cpp
+        # This allows us to reuse signatures created in the unit test framework.
+        self.tx1 = create_coinbase()                 # this has a bip34 scriptsig,
+        self.tx1.vin[0].scriptSig = CScript([0, 0])  # but this matches the unit tests
+        self.tx1.vout[0].nValue = 0
+        self.tx1.vout[0].scriptPubKey = scriptPubKey
+        self.tx1.rehash()
+    def create_spend_tx(self, scriptSig):
+        self.tx2 = create_transaction(self.tx1, 0, CScript(), 0)
+        self.tx2.vin[0].scriptSig = scriptSig
+        self.tx2.vout[0].scriptPubKey = CScript()
+        self.tx2.rehash()
+    def rehash(self):
+        self.tx1.rehash()
+        self.tx2.rehash()
+
+# This test uses the (default) two nodes provided by ComparisonTestFramework,
+# specified on the command line with --testbinary and --refbinary.
+# See comptool.py
+class ScriptTest(ComparisonTestFramework):
+
+    def run_test(self):
+        # Set up the comparison tool TestManager
+        test = TestManager(self, self.options.tmpdir)
+        test.add_all_connections(self.nodes)
+
+        # Load scripts
+        self.scripts = ScriptTestFile([script_valid_file, script_invalid_file])
+        self.scripts.load_files()
+
+        # Some variables we re-use between test instances (to build blocks)
+        self.tip = None
+        self.block_time = None
+
+        NetworkThread().start()  # Start up network handling in another thread
+        test.run()
+
+    def generate_test_instance(self, pubkeystring, scriptsigstring):
+        scriptpubkey = ParseScript(pubkeystring)
+        scriptsig = ParseScript(scriptsigstring)
+
+        test = TestInstance(sync_every_block=False)
+        test_build = TestBuilder()
+        test_build.create_credit_tx(scriptpubkey)
+        test_build.create_spend_tx(scriptsig)
+        test_build.rehash()
+
+        block = create_block(self.tip, test_build.tx1, self.block_time)
+        self.block_time += 1
+        block.solve()
+        self.tip = block.sha256
+        test.blocks_and_transactions = [[block, True]]
+
+        for i in xrange(100):
+            block = create_block(self.tip, create_coinbase(), self.block_time)
+            self.block_time += 1
+            block.solve()
+            self.tip = block.sha256
+            test.blocks_and_transactions.append([block, True])
+
+        block = create_block(self.tip, create_coinbase(), self.block_time)
+        self.block_time += 1
+        block.vtx.append(test_build.tx2)
+        block.hashMerkleRoot = block.calc_merkle_root()
+        block.rehash()
+        block.solve()
+        test.blocks_and_transactions.append([block, None])
+        return test   
+
+    # This generates the tests for TestManager.
+    def get_tests(self):
+        self.tip = int ("0x" + self.nodes[0].getbestblockhash() + "L", 0)
+        self.block_time = 1333230000  # before the BIP16 switchover
+
+        '''
+        Create a new block with an anyone-can-spend coinbase
+        '''
+        block = create_block(self.tip, create_coinbase(), self.block_time)
+        self.block_time += 1
+        block.solve()
+        self.tip = block.sha256
+        yield TestInstance(objects=[[block, True]])
+
+        '''
+        Build out to 100 blocks total, maturing the coinbase.
+        '''
+        test = TestInstance(objects=[], sync_every_block=False, sync_every_tx=False)
+        for i in xrange(100):
+            b = create_block(self.tip, create_coinbase(), self.block_time)
+            b.solve()
+            test.blocks_and_transactions.append([b, True])
+            self.tip = b.sha256
+            self.block_time += 1
+        yield test
+ 
+        ''' Iterate through script tests. '''
+        counter = 0
+        for script_test in self.scripts.get_records():
+            ''' Reset the blockchain to genesis block + 100 blocks. '''
+            if self.nodes[0].getblockcount() > 101:
+                self.nodes[0].invalidateblock(self.nodes[0].getblockhash(102))
+                self.nodes[1].invalidateblock(self.nodes[1].getblockhash(102))
+
+            self.tip = int ("0x" + self.nodes[0].getbestblockhash() + "L", 0)
+
+            [scriptsig, scriptpubkey, flags] = script_test[0:3]
+            flags = ParseScriptFlags(flags)
+
+            # We can use block time to determine whether the nodes should be
+            # enforcing BIP16.
+            #
+            # We intentionally let the block time grow by 1 each time.
+            # This forces the block hashes to differ between tests, so that
+            # a call to invalidateblock doesn't interfere with a later test.
+            if (flags & SCRIPT_VERIFY_P2SH):
+                self.block_time = 1333238400 + counter # Advance to enforcing BIP16
+            else:
+                self.block_time = 1333230000 + counter # Before the BIP16 switchover
+
+            print "Script test: [%s]" % script_test
+
+            yield self.generate_test_instance(scriptpubkey, scriptsig)
+            counter += 1
+
+if __name__ == '__main__':
+    ScriptTest().main()