1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
|
#!/usr/bin/env python3
# Copyright (c) 2015-2016 The Bitcoin Core developers
# Distributed under the MIT software license, see the accompanying
# file COPYING or http://www.opensource.org/licenses/mit-license.php.
"""Utilities for manipulating blocks and transactions."""
from .address import (
key_to_p2sh_p2wpkh,
key_to_p2wpkh,
script_to_p2sh_p2wsh,
script_to_p2wsh,
)
from .mininode import *
from .script import (
CScript,
OP_0,
OP_1,
OP_CHECKMULTISIG,
OP_CHECKSIG,
OP_RETURN,
OP_TRUE,
hash160,
)
from .util import assert_equal
# Create a block (with regtest difficulty)
def create_block(hashprev, coinbase, nTime=None):
block = CBlock()
if nTime is None:
import time
block.nTime = int(time.time()+600)
else:
block.nTime = nTime
block.hashPrevBlock = hashprev
block.nBits = 0x207fffff # Will break after a difficulty adjustment...
block.vtx.append(coinbase)
block.hashMerkleRoot = block.calc_merkle_root()
block.calc_sha256()
return block
# From BIP141
WITNESS_COMMITMENT_HEADER = b"\xaa\x21\xa9\xed"
def get_witness_script(witness_root, witness_nonce):
witness_commitment = uint256_from_str(hash256(ser_uint256(witness_root)+ser_uint256(witness_nonce)))
output_data = WITNESS_COMMITMENT_HEADER + ser_uint256(witness_commitment)
return CScript([OP_RETURN, output_data])
# According to BIP141, blocks with witness rules active must commit to the
# hash of all in-block transactions including witness.
def add_witness_commitment(block, nonce=0):
# First calculate the merkle root of the block's
# transactions, with witnesses.
witness_nonce = nonce
witness_root = block.calc_witness_merkle_root()
# witness_nonce should go to coinbase witness.
block.vtx[0].wit.vtxinwit = [CTxInWitness()]
block.vtx[0].wit.vtxinwit[0].scriptWitness.stack = [ser_uint256(witness_nonce)]
# witness commitment is the last OP_RETURN output in coinbase
block.vtx[0].vout.append(CTxOut(0, get_witness_script(witness_root, witness_nonce)))
block.vtx[0].rehash()
block.hashMerkleRoot = block.calc_merkle_root()
block.rehash()
def serialize_script_num(value):
r = bytearray(0)
if value == 0:
return r
neg = value < 0
absvalue = -value if neg else value
while (absvalue):
r.append(int(absvalue & 0xff))
absvalue >>= 8
if r[-1] & 0x80:
r.append(0x80 if neg else 0)
elif neg:
r[-1] |= 0x80
return r
# Create a coinbase transaction, assuming no miner fees.
# If pubkey is passed in, the coinbase output will be a P2PK output;
# otherwise an anyone-can-spend output.
def create_coinbase(height, pubkey = None):
coinbase = CTransaction()
coinbase.vin.append(CTxIn(COutPoint(0, 0xffffffff),
ser_string(serialize_script_num(height)), 0xffffffff))
coinbaseoutput = CTxOut()
coinbaseoutput.nValue = 50 * COIN
halvings = int(height/150) # regtest
coinbaseoutput.nValue >>= halvings
if (pubkey != None):
coinbaseoutput.scriptPubKey = CScript([pubkey, OP_CHECKSIG])
else:
coinbaseoutput.scriptPubKey = CScript([OP_TRUE])
coinbase.vout = [ coinbaseoutput ]
coinbase.calc_sha256()
return coinbase
# Create a transaction.
# If the scriptPubKey is not specified, make it anyone-can-spend.
def create_transaction(prevtx, n, sig, value, scriptPubKey=CScript()):
tx = CTransaction()
assert(n < len(prevtx.vout))
tx.vin.append(CTxIn(COutPoint(prevtx.sha256, n), sig, 0xffffffff))
tx.vout.append(CTxOut(value, scriptPubKey))
tx.calc_sha256()
return tx
def get_legacy_sigopcount_block(block, fAccurate=True):
count = 0
for tx in block.vtx:
count += get_legacy_sigopcount_tx(tx, fAccurate)
return count
def get_legacy_sigopcount_tx(tx, fAccurate=True):
count = 0
for i in tx.vout:
count += i.scriptPubKey.GetSigOpCount(fAccurate)
for j in tx.vin:
# scriptSig might be of type bytes, so convert to CScript for the moment
count += CScript(j.scriptSig).GetSigOpCount(fAccurate)
return count
# Create a scriptPubKey corresponding to either a P2WPKH output for the
# given pubkey, or a P2WSH output of a 1-of-1 multisig for the given
# pubkey. Returns the hex encoding of the scriptPubKey.
def witness_script(use_p2wsh, pubkey):
if (use_p2wsh == False):
# P2WPKH instead
pubkeyhash = hash160(hex_str_to_bytes(pubkey))
pkscript = CScript([OP_0, pubkeyhash])
else:
# 1-of-1 multisig
witness_program = CScript([OP_1, hex_str_to_bytes(pubkey), OP_1, OP_CHECKMULTISIG])
scripthash = sha256(witness_program)
pkscript = CScript([OP_0, scripthash])
return bytes_to_hex_str(pkscript)
# Return a transaction (in hex) that spends the given utxo to a segwit output,
# optionally wrapping the segwit output using P2SH.
def create_witness_tx(node, use_p2wsh, utxo, pubkey, encode_p2sh, amount):
if use_p2wsh:
program = CScript([OP_1, hex_str_to_bytes(pubkey), OP_1, OP_CHECKMULTISIG])
addr = script_to_p2sh_p2wsh(program) if encode_p2sh else script_to_p2wsh(program)
else:
addr = key_to_p2sh_p2wpkh(pubkey) if encode_p2sh else key_to_p2wpkh(pubkey)
if not encode_p2sh:
assert_equal(node.validateaddress(addr)['scriptPubKey'], witness_script(use_p2wsh, pubkey))
return node.createrawtransaction([utxo], {addr: amount})
# Create a transaction spending a given utxo to a segwit output corresponding
# to the given pubkey: use_p2wsh determines whether to use P2WPKH or P2WSH;
# encode_p2sh determines whether to wrap in P2SH.
# sign=True will have the given node sign the transaction.
# insert_redeem_script will be added to the scriptSig, if given.
def send_to_witness(use_p2wsh, node, utxo, pubkey, encode_p2sh, amount, sign=True, insert_redeem_script=""):
tx_to_witness = create_witness_tx(node, use_p2wsh, utxo, pubkey, encode_p2sh, amount)
if (sign):
signed = node.signrawtransaction(tx_to_witness)
assert("errors" not in signed or len(["errors"]) == 0)
return node.sendrawtransaction(signed["hex"])
else:
if (insert_redeem_script):
tx = FromHex(CTransaction(), tx_to_witness)
tx.vin[0].scriptSig += CScript([hex_str_to_bytes(insert_redeem_script)])
tx_to_witness = ToHex(tx)
return node.sendrawtransaction(tx_to_witness)
|