commit e13183ea7a4d43c861a973f4792980d637005074
parent 97296432a2bcbdc13979d94f67e283666344c7e9
Author: SomberNight <somber.night@protonmail.com>
Date: Fri, 27 Apr 2018 15:38:44 +0200
bitcoin.py: SCRIPT-related clean-up. transaction.py: construct_witness
Diffstat:
3 files changed, 47 insertions(+), 38 deletions(-)
diff --git a/lib/bitcoin.py b/lib/bitcoin.py
@@ -152,7 +152,7 @@ def int_to_hex(i, length=1):
s = "0"*(2*length - len(s)) + s
return rev_hex(s)
-def script_num_to_hex(i):
+def script_num_to_hex(i: int) -> str:
"""See CScriptNum in Bitcoin Core.
Encodes an integer as hex, to be used in script.
@@ -176,7 +176,7 @@ def script_num_to_hex(i):
return bh2u(result)
-def var_int(i):
+def var_int(i: int) -> str:
# https://en.bitcoin.it/wiki/Protocol_specification#Variable_length_integer
if i<0xfd:
return int_to_hex(i)
@@ -188,14 +188,14 @@ def var_int(i):
return "ff"+int_to_hex(i,8)
-def witness_push(item):
- """ Returns data in the form it should be present in the witness.
+def witness_push(item: str) -> str:
+ """Returns data in the form it should be present in the witness.
hex -> hex
"""
return var_int(len(item) // 2) + item
-def op_push(i):
+def op_push(i: int) -> str:
if i<0x4c: # OP_PUSHDATA1
return int_to_hex(i)
elif i<=0xff:
@@ -206,36 +206,32 @@ def op_push(i):
return '4e' + int_to_hex(i,4)
-def add_data_to_script(data):
+def push_script(data: str) -> str:
"""Returns pushed data to the script, automatically
choosing canonical opcodes depending on the length of the data.
- bytes -> bytes
+ hex -> hex
ported from https://github.com/btcsuite/btcd/blob/fdc2bc867bda6b351191b5872d2da8270df00d13/txscript/scriptbuilder.go#L128
"""
- assert_bytes(data)
+ data = bfh(data)
from .transaction import opcodes
data_len = len(data)
# "small integer" opcodes
if data_len == 0 or data_len == 1 and data[0] == 0:
- return bytes([opcodes.OP_0])
+ return bh2u(bytes([opcodes.OP_0]))
elif data_len == 1 and data[0] <= 16:
- return bytes([opcodes.OP_1 - 1 + data[0]])
+ return bh2u(bytes([opcodes.OP_1 - 1 + data[0]]))
elif data_len == 1 and data[0] == 0x81:
- return bytes([opcodes.OP_1NEGATE])
-
- return bfh(push_script(bh2u(data)))
+ return bh2u(bytes([opcodes.OP_1NEGATE]))
+ return op_push(data_len) + bh2u(data)
-def add_number_to_script(i):
- """int -> bytes"""
- return add_data_to_script(bfh(script_num_to_hex(i)))
+def add_number_to_script(i: int) -> bytes:
+ return bfh(push_script(script_num_to_hex(i)))
-def push_script(x):
- return op_push(len(x)//2) + x
def sha256(x):
x = to_bytes(x, 'utf8')
diff --git a/lib/tests/test_bitcoin.py b/lib/tests/test_bitcoin.py
@@ -12,9 +12,9 @@ from lib.bitcoin import (
verify_message, deserialize_privkey, serialize_privkey, is_segwit_address,
is_b58_address, address_to_scripthash, is_minikey, is_compressed, is_xpub,
xpub_type, is_xprv, is_bip32_derivation, seed_type, EncodeBase58Check,
- script_num_to_hex, add_data_to_script, add_number_to_script)
+ script_num_to_hex, push_script, add_number_to_script)
from lib.transaction import opcodes
-from lib.util import bfh
+from lib.util import bfh, bh2u
from lib import constants
from . import TestCaseForTestnet
@@ -167,19 +167,19 @@ class Test_bitcoin(unittest.TestCase):
self.assertEqual(script_num_to_hex(32768), '008000')
self.assertEqual(script_num_to_hex(-32768), '008080')
- def test_add_data_to_script(self):
+ def test_push_script(self):
# https://github.com/bitcoin/bips/blob/master/bip-0062.mediawiki#push-operators
- self.assertEqual(add_data_to_script(bfh('')), bytes([opcodes.OP_0]))
- self.assertEqual(add_data_to_script(bfh('07')), bytes([opcodes.OP_7]))
- self.assertEqual(add_data_to_script(bfh('10')), bytes([opcodes.OP_16]))
- self.assertEqual(add_data_to_script(bfh('81')), bytes([opcodes.OP_1NEGATE]))
- self.assertEqual(add_data_to_script(bfh('11')), bfh('0111'))
- self.assertEqual(add_data_to_script(bfh(75 * '42')), bfh('4b' + 75 * '42'))
- self.assertEqual(add_data_to_script(bfh(76 * '42')), bytes([opcodes.OP_PUSHDATA1]) + bfh('4c' + 76 * '42'))
- self.assertEqual(add_data_to_script(bfh(100 * '42')), bytes([opcodes.OP_PUSHDATA1]) + bfh('64' + 100 * '42'))
- self.assertEqual(add_data_to_script(bfh(255 * '42')), bytes([opcodes.OP_PUSHDATA1]) + bfh('ff' + 255 * '42'))
- self.assertEqual(add_data_to_script(bfh(256 * '42')), bytes([opcodes.OP_PUSHDATA2]) + bfh('0001' + 256 * '42'))
- self.assertEqual(add_data_to_script(bfh(520 * '42')), bytes([opcodes.OP_PUSHDATA2]) + bfh('0802' + 520 * '42'))
+ self.assertEqual(push_script(''), bh2u(bytes([opcodes.OP_0])))
+ self.assertEqual(push_script('07'), bh2u(bytes([opcodes.OP_7])))
+ self.assertEqual(push_script('10'), bh2u(bytes([opcodes.OP_16])))
+ self.assertEqual(push_script('81'), bh2u(bytes([opcodes.OP_1NEGATE])))
+ self.assertEqual(push_script('11'), '0111')
+ self.assertEqual(push_script(75 * '42'), '4b' + 75 * '42')
+ self.assertEqual(push_script(76 * '42'), bh2u(bytes([opcodes.OP_PUSHDATA1]) + bfh('4c' + 76 * '42')))
+ self.assertEqual(push_script(100 * '42'), bh2u(bytes([opcodes.OP_PUSHDATA1]) + bfh('64' + 100 * '42')))
+ self.assertEqual(push_script(255 * '42'), bh2u(bytes([opcodes.OP_PUSHDATA1]) + bfh('ff' + 255 * '42')))
+ self.assertEqual(push_script(256 * '42'), bh2u(bytes([opcodes.OP_PUSHDATA2]) + bfh('0001' + 256 * '42')))
+ self.assertEqual(push_script(520 * '42'), bh2u(bytes([opcodes.OP_PUSHDATA2]) + bfh('0802' + 520 * '42')))
def test_add_number_to_script(self):
# https://github.com/bitcoin/bips/blob/master/bip-0062.mediawiki#numbers
diff --git a/lib/transaction.py b/lib/transaction.py
@@ -27,6 +27,8 @@
# Note: The deserialization code originally comes from ABE.
+from typing import Sequence, Union
+
from .util import print_error, profiler
from . import bitcoin
@@ -236,7 +238,7 @@ opcodes = Enumeration("Opcodes", [
])
-def script_GetOp(_bytes):
+def script_GetOp(_bytes : bytes):
i = 0
while i < len(_bytes):
vch = None
@@ -382,7 +384,7 @@ def parse_scriptSig(d, _bytes):
bh2u(_bytes))
-def parse_redeemScript_multisig(redeem_script):
+def parse_redeemScript_multisig(redeem_script: bytes):
dec2 = [ x for x in script_GetOp(redeem_script) ]
try:
m = dec2[0][0] - opcodes.OP_1 + 1
@@ -464,6 +466,18 @@ def parse_input(vds):
return d
+def construct_witness(items: Sequence[Union[str, int, bytes]]) -> str:
+ """Constructs a witness from the given stack items."""
+ witness = var_int(len(items))
+ for item in items:
+ if type(item) is int:
+ item = bitcoin.script_num_to_hex(item)
+ elif type(item) is bytes:
+ item = bh2u(item)
+ witness += bitcoin.witness_push(item)
+ return witness
+
+
def parse_witness(vds, txin):
n = vds.read_compact_size()
if n == 0:
@@ -474,7 +488,7 @@ def parse_witness(vds, txin):
# now 'n' is the number of items in the witness
w = list(bh2u(vds.read_bytes(vds.read_compact_size())) for i in range(n))
- txin['witness'] = var_int(n) + ''.join(witness_push(i) for i in w)
+ txin['witness'] = construct_witness(w)
# FIXME: witness version > 0 will probably fail here.
# For native segwit, we would need the scriptPubKey of the parent txn
@@ -750,11 +764,10 @@ class Transaction:
if witness is None:
pubkeys, sig_list = self.get_siglist(txin, estimate_size)
if txin['type'] in ['p2wpkh', 'p2wpkh-p2sh']:
- witness = var_int(2) + witness_push(sig_list[0]) + witness_push(pubkeys[0])
+ witness = construct_witness([sig_list[0], pubkeys[0]])
elif txin['type'] in ['p2wsh', 'p2wsh-p2sh']:
- n = len(sig_list) + 2
witness_script = multisig_script(pubkeys, txin['num_sig'])
- witness = var_int(n) + '00' + ''.join(witness_push(x) for x in sig_list) + witness_push(witness_script)
+ witness = construct_witness([0, *sig_list, witness_script])
else:
raise Exception('wrong txin type:', txin['type'])
if self.is_txin_complete(txin) or estimate_size:
