zebra.lucky
/
joinmarket-clientserver
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity
Browse Source

segwit backend support

master
Adam Gibson 9 years ago
parent
28912acb5f
commit
671e689495
No known key found for this signature in database
GPG Key ID: B3AE09F1E9A3197A
2 changed files with 128 additions and 15 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 141
      jmbitcoin/jmbitcoin/secp256k1_transaction.py
  2. 2
      jmclient/test/test_tx_creation.py

141
jmbitcoin/jmbitcoin/secp256k1_transaction.py
Unescape View File

@ -42,7 +42,6 @@ def json_changebase(obj, changer):
# Transaction serialization and deserialization
def deserialize(tx):
if isinstance(tx, str) and re.match('^[0-9a-fA-F]*$', tx):
#tx = bytes(bytearray.fromhex(tx))
@ -53,6 +52,7 @@ def deserialize(tx):
# so that it is call-by-reference
pos = [0]
#TODO: these are disgustingly ignorant of overrun errors!
def read_as_int(bytez):
pos[0] += bytez
return decode(tx[pos[0] - bytez:pos[0]][::-1], 256)
@ -73,8 +73,22 @@ def deserialize(tx):
size = read_var_int()
return read_bytes(size)
def read_flag_byte(val):
flag = read_bytes(1)
if from_byte_to_int(flag)==val:
return True
else:
pos[0] -= 1
return False
obj = {"ins": [], "outs": []}
obj["version"] = read_as_int(4)
segwit = False
if read_flag_byte(0): segwit = True
if segwit:
if not read_flag_byte(1): #BIP141 is currently "MUST" ==1
raise Exception("Invalid segwit transaction format")
ins = read_var_int()
for i in range(ins):
obj["ins"].append({
@ -82,6 +96,7 @@ def deserialize(tx):
"hash": read_bytes(32)[::-1],
"index": read_as_int(4)
},
#TODO this will probably crap out on null for segwit
"script": read_var_string(),
"sequence": read_as_int(4)
})
@ -91,13 +106,29 @@ def deserialize(tx):
"value": read_as_int(8),
"script": read_var_string()
})
#segwit flag is only set if at least one txinwitness exists,
#in other words it would have to be at least partially signed;
#and, if it is, the witness section must be properly created
#including "00" for any input that either does not YET or will not
#have a witness attached.
if segwit:
#read witness data
#there must be one witness object for each txin
#technically, we could parse the contents of the witness
#into objects, but we'll just replicate the behaviour of the
#rpc decoderawtx, and attach a "txinwitness" for each in, with
#the items in the witness space separated
for i in range(ins):
num_items = read_var_int()
items = []
for ni in range(num_items):
items.append(read_var_string())
obj["ins"][i]["txinwitness"] = items
obj["locktime"] = read_as_int(4)
return obj
def serialize(txobj):
#if isinstance(txobj, bytes):
# txobj = bytes_to_hex_string(txobj)
o = []
if json_is_base(txobj, 16):
json_changedbase = json_changebase(txobj,
@ -105,6 +136,13 @@ def serialize(txobj):
hexlified = safe_hexlify(serialize(json_changedbase))
return hexlified
o.append(encode(txobj["version"], 256, 4)[::-1])
segwit = False
if any("txinwitness" in x.keys() for x in txobj["ins"]):
segwit = True
if segwit:
#append marker and flag
o.append('\x00')
o.append('\x01')
o.append(num_to_var_int(len(txobj["ins"])))
for inp in txobj["ins"]:
o.append(inp["outpoint"]["hash"][::-1])
@ -116,6 +154,17 @@ def serialize(txobj):
for out in txobj["outs"]:
o.append(encode(out["value"], 256, 8)[::-1])
o.append(num_to_var_int(len(out["script"])) + out["script"])
if segwit:
#number of witnesses is not explicitly encoded;
#it's implied by txin length
for inp in txobj["ins"]:
if "txinwitness" not in inp.keys():
o.append('\x00')
continue
items = inp["txinwitness"]
o.append(num_to_var_int(len(items)))
for item in items:
o.append(num_to_var_int(len(item)) + item)
o.append(encode(txobj["locktime"], 256, 4)[::-1])
return ''.join(o) if is_python2 else reduce(lambda x, y: x + y, o, bytes())
@ -127,6 +176,45 @@ SIGHASH_NONE = 2
SIGHASH_SINGLE = 3
SIGHASH_ANYONECANPAY = 0x80
def segwit_signature_form(txobj, i, script, amount, hashcode=SIGHASH_ALL):
"""Given a deserialized transaction txobj, an input index i,
which spends from a witness,
a script for redemption and an amount in satoshis, prepare
the version of the transaction to be hashed and signed.
"""
#if isinstance(txobj, string_or_bytes_types):
# return serialize(segwit_signature_form(deserialize(txobj), i, script,
# amount, hashcode))
script = binascii.unhexlify(script)
nVersion = encode(txobj["version"], 256, 4)[::-1]
#create hashPrevouts preimage
pi = ""
for inp in txobj["ins"]:
pi += binascii.unhexlify(inp["outpoint"]["hash"])[::-1]
pi += encode(inp["outpoint"]["index"], 256, 4)[::-1]
hashPrevouts = bin_dbl_sha256(pi)
#create hashSequence preimage
pi = ""
for inp in txobj["ins"]:
pi += encode(inp["sequence"], 256, 4)[::-1]
hashSequence = bin_dbl_sha256(pi)
#add this input's outpoint
thisOut = binascii.unhexlify(txobj["ins"][i]["outpoint"]["hash"])[::-1]
thisOut += encode(txobj["ins"][i]["outpoint"]["index"], 256, 4)[::-1]
scriptCode = num_to_var_int(len(script)) + script
amt = encode(amount, 256, 8)[::-1]
thisSeq = encode(txobj["ins"][i]["sequence"], 256, 4)[::-1]
#create hashOutputs preimage
pi = ""
for out in txobj["outs"]:
pi += encode(out["value"], 256, 8)[::-1]
pi += (num_to_var_int(len(binascii.unhexlify(out["script"]))) + \
binascii.unhexlify(out["script"]))
hashOutputs = bin_dbl_sha256(pi)
nLockTime = encode(txobj["locktime"], 256, 4)[::-1]
return nVersion + hashPrevouts + hashSequence + thisOut + scriptCode + amt + \
thisSeq + hashOutputs + nLockTime
def signature_form(tx, i, script, hashcode=SIGHASH_ALL):
i, hashcode = int(i), int(hashcode)
if isinstance(tx, string_or_bytes_types):
@ -219,13 +307,9 @@ def script_to_address(script, vbyte=0):
script) == 25:
return bin_to_b58check(script[3:-2], vbyte) # pubkey hash addresses
else:
if vbyte in [111, 196]:
# Testnet
scripthash_byte = 196
else:
scripthash_byte = 5
# BIP0016 scripthash addresses
return bin_to_b58check(script[2:-1], scripthash_byte)
# BIP0016 scripthash addresses: requires explicit vbyte set
if vbyte == 0: raise Exception("Invalid version byte for P2SH")
return bin_to_b58check(script[2:-1], vbyte)
def p2sh_scriptaddr(script, magicbyte=5):
@ -305,6 +389,7 @@ if is_python2:
else: #pragma: no cover
def serialize_script(script):
#TODO Python 3 bugfix as above needed
if json_is_base(script, 16):
return safe_hexlify(serialize_script(json_changebase(
script, lambda x: binascii.unhexlify(x))))
@ -326,7 +411,7 @@ def mk_multisig_script(*args): # [pubs],k or pub1,pub2...pub[n],k
# Signing and verifying
def verify_tx_input(tx, i, script, sig, pub):
def verify_tx_input(tx, i, script, sig, pub, witness=None, amount=None):
if re.match('^[0-9a-fA-F]*$', tx):
tx = binascii.unhexlify(tx)
if re.match('^[0-9a-fA-F]*$', script):
@ -335,18 +420,30 @@ def verify_tx_input(tx, i, script, sig, pub):
sig = safe_hexlify(sig)
if not re.match('^[0-9a-fA-F]*$', pub):
pub = safe_hexlify(pub)
if witness:
if not re.match('^[0-9a-fA-F]*$', witness):
witness = safe_hexlify(witness)
hashcode = decode(sig[-2:], 16)
modtx = signature_form(tx, int(i), script, hashcode)
if witness and amount:
#TODO assumes p2sh wrapped segwit input; OK for JM wallets
scriptCode = "76a914"+hash160(binascii.unhexlify(pub))+"88ac"
modtx = segwit_signature_form(deserialize(binascii.hexlify(tx)), int(i),
scriptCode, amount, hashcode)
else:
modtx = signature_form(tx, int(i), script, hashcode)
return ecdsa_tx_verify(modtx, sig, pub, hashcode)
def sign(tx, i, priv, hashcode=SIGHASH_ALL, usenonce=None):
def sign(tx, i, priv, hashcode=SIGHASH_ALL, usenonce=None, amount=None):
i = int(i)
if (not is_python2 and isinstance(re, bytes)) or not re.match(
'^[0-9a-fA-F]*$', tx):
return binascii.unhexlify(sign(safe_hexlify(tx), i, priv))
if len(priv) <= 33:
priv = safe_hexlify(priv)
if amount:
return p2sh_p2wpkh_sign(tx, i, priv, amount, hashcode=hashcode,
usenonce=usenonce)
pub = privkey_to_pubkey(priv, True)
address = pubkey_to_address(pub)
signing_tx = signature_form(tx, i, mk_pubkey_script(address), hashcode)
@ -355,6 +452,22 @@ def sign(tx, i, priv, hashcode=SIGHASH_ALL, usenonce=None):
txobj["ins"][i]["script"] = serialize_script([sig, pub])
return serialize(txobj)
def p2sh_p2wpkh_sign(tx, i, priv, amount, hashcode=SIGHASH_ALL, usenonce=None):
"""Given a serialized transaction, index, private key in hex,
amount in satoshis and optionally hashcode, return the serialized
transaction containing a signature and witness for this input; it's
assumed that the input is of type pay-to-witness-pubkey-hash nested in p2sh.
"""
pub = privkey_to_pubkey(priv)
script = pubkey_to_p2sh_p2wpkh_script(pub)
scriptCode = "76a914"+hash160(binascii.unhexlify(pub))+"88ac"
signing_tx = segwit_signature_form(deserialize(tx), i, scriptCode, amount,
hashcode=hashcode)
sig = ecdsa_tx_sign(signing_tx, priv, hashcode, usenonce=usenonce)
txobj = deserialize(tx)
txobj["ins"][i]["script"] = "16"+script
txobj["ins"][i]["txinwitness"] = [sig, pub]
return serialize(txobj)
def signall(tx, priv):
# if priv is a dictionary, assume format is

2
jmclient/test/test_tx_creation.py
Unescape View File

@ -55,7 +55,7 @@ def test_create_p2sh_output_tx(setup_tx_creation, nw, wallet_structures,
def test_script_to_address(setup_tx_creation):
sample_script = "a914307f099a3bfedec9a09682238db491bade1b467f87"
assert bitcoin.script_to_address(
sample_script) == "367SYUMqo1Fi4tQsycnmCtB6Ces1Z7EZLH"
sample_script, vbyte=5) == "367SYUMqo1Fi4tQsycnmCtB6Ces1Z7EZLH"
assert bitcoin.script_to_address(
sample_script, vbyte=196) == "2MwfecDHsQTm4Gg3RekQdpqAMR15BJrjfRF"

Write Preview
Loading…
Cancel
Save