def input_script(self,
txin: PartialTxInput,
*,
estimate_size=False):
if txin.script_type == 'p2pkh':
return Transaction.get_preimage_script(txin)
raise Exception("unsupported type %s" % txin.script_type)
def sign_transaction(self, tx, password):
if tx.is_complete():
return
inputs = []
inputsPaths = []
chipInputs = []
redeemScripts = []
changePath = ""
output = None
p2shTransaction = False
segwitTransaction = False
pin = ""
client_ledger = self.get_client(
) # prompt for the PIN before displaying the dialog if necessary
client_electrum = self.get_client_electrum()
assert client_electrum
# Fetch inputs of the transaction to sign
for txin in tx.inputs():
if txin.is_coinbase_input():
self.give_error(
"Coinbase not supported") # should never happen
if txin.script_type in ['p2sh']:
p2shTransaction = True
if txin.script_type in ['p2wpkh-p2sh', 'p2wsh-p2sh']:
if not client_electrum.supports_segwit():
self.give_error(MSG_NEEDS_FW_UPDATE_SEGWIT)
segwitTransaction = True
if txin.script_type in ['p2wpkh', 'p2wsh']:
if not client_electrum.supports_native_segwit():
self.give_error(MSG_NEEDS_FW_UPDATE_SEGWIT)
segwitTransaction = True
my_pubkey, full_path = self.find_my_pubkey_in_txinout(txin)
if not full_path:
self.give_error("No matching pubkey for sign_transaction"
) # should never happen
full_path = convert_bip32_intpath_to_strpath(full_path)[2:]
redeemScript = Transaction.get_preimage_script(txin)
txin_prev_tx = txin.utxo
if txin_prev_tx is None and not txin.is_segwit():
raise UserFacingException(
_('Missing previous tx for legacy input.'))
txin_prev_tx_raw = txin_prev_tx.serialize(
) if txin_prev_tx else None
inputs.append([
txin_prev_tx_raw, txin.prevout.out_idx, redeemScript,
txin.prevout.txid.hex(), my_pubkey, txin.nsequence,
txin.value_sats()
])
inputsPaths.append(full_path)
# Sanity check
if p2shTransaction:
for txin in tx.inputs():
if txin.script_type != 'p2sh':
self.give_error(
"P2SH / regular input mixed in same transaction not supported"
) # should never happen
txOutput = var_int(len(tx.outputs()))
for o in tx.outputs():
txOutput += int_to_hex(o.value, 8)
script = o.scriptpubkey.hex()
txOutput += var_int(len(script) // 2)
txOutput += script
txOutput = bfh(txOutput)
if not client_electrum.supports_multi_output():
if len(tx.outputs()) > 2:
self.give_error(
"Transaction with more than 2 outputs not supported")
for txout in tx.outputs():
if client_electrum.is_hw1(
) and txout.address and not is_b58_address(txout.address):
self.give_error(
_("This {} device can only send to base58 addresses.").
format(self.device))
if not txout.address:
if client_electrum.is_hw1():
self.give_error(
_("Only address outputs are supported by {}").format(
self.device))
# note: max_size based on https://github.com/LedgerHQ/ledger-app-btc/commit/3a78dee9c0484821df58975803e40d58fbfc2c38#diff-c61ccd96a6d8b54d48f54a3bc4dfa7e2R26
validate_op_return_output(txout, max_size=190)
# Output "change" detection
# - only one output and one change is authorized (for hw.1 and nano)
# - at most one output can bypass confirmation (~change) (for all)
if not p2shTransaction:
has_change = False
any_output_on_change_branch = is_any_tx_output_on_change_branch(tx)
for txout in tx.outputs():
if txout.is_mine and len(tx.outputs()) > 1 \
and not has_change:
# prioritise hiding outputs on the 'change' branch from user
# because no more than one change address allowed
if txout.is_change == any_output_on_change_branch:
my_pubkey, changePath = self.find_my_pubkey_in_txinout(
txout)
assert changePath
changePath = convert_bip32_intpath_to_strpath(
changePath)[2:]
has_change = True
else:
output = txout.address
else:
output = txout.address
self.handler.show_message(
_("Confirm Transaction on your Ledger device..."))
try:
# Get trusted inputs from the original transactions
for utxo in inputs:
sequence = int_to_hex(utxo[5], 4)
if segwitTransaction and not client_electrum.supports_segwit_trustedInputs(
):
tmp = bfh(utxo[3])[::-1]
tmp += bfh(int_to_hex(utxo[1], 4))
tmp += bfh(int_to_hex(utxo[6], 8)) # txin['value']
chipInputs.append({
'value': tmp,
'witness': True,
'sequence': sequence
})
redeemScripts.append(bfh(utxo[2]))
elif (not p2shTransaction
) or client_electrum.supports_multi_output():
txtmp = bitcoinTransaction(bfh(utxo[0]))
trustedInput = client_ledger.getTrustedInput(
txtmp, utxo[1])
trustedInput['sequence'] = sequence
if segwitTransaction:
trustedInput['witness'] = True
chipInputs.append(trustedInput)
if p2shTransaction or segwitTransaction:
redeemScripts.append(bfh(utxo[2]))
else:
redeemScripts.append(txtmp.outputs[utxo[1]].script)
else:
tmp = bfh(utxo[3])[::-1]
tmp += bfh(int_to_hex(utxo[1], 4))
chipInputs.append({'value': tmp, 'sequence': sequence})
redeemScripts.append(bfh(utxo[2]))
# Sign all inputs
firstTransaction = True
inputIndex = 0
rawTx = tx.serialize_to_network()
client_ledger.enableAlternate2fa(False)
if segwitTransaction:
client_ledger.startUntrustedTransaction(
True,
inputIndex,
chipInputs,
redeemScripts[inputIndex],
version=tx.version)
# we don't set meaningful outputAddress, amount and fees
# as we only care about the alternateEncoding==True branch
outputData = client_ledger.finalizeInput(
b'', 0, 0, changePath, bfh(rawTx))
outputData['outputData'] = txOutput
if outputData['confirmationNeeded']:
outputData['address'] = output
self.handler.finished()
# do the authenticate dialog and get pin:
pin = self.handler.get_auth(outputData,
client=client_electrum)
if not pin:
raise UserWarning()
self.handler.show_message(
_("Confirmed. Signing Transaction..."))
while inputIndex < len(inputs):
singleInput = [chipInputs[inputIndex]]
client_ledger.startUntrustedTransaction(
False,
0,
singleInput,
redeemScripts[inputIndex],
version=tx.version)
inputSignature = client_ledger.untrustedHashSign(
inputsPaths[inputIndex], pin, lockTime=tx.locktime)
inputSignature[0] = 0x30 # force for 1.4.9+
my_pubkey = inputs[inputIndex][4]
tx.add_signature_to_txin(txin_idx=inputIndex,
signing_pubkey=my_pubkey.hex(),
sig=inputSignature.hex())
inputIndex = inputIndex + 1
else:
while inputIndex < len(inputs):
client_ledger.startUntrustedTransaction(
firstTransaction,
inputIndex,
chipInputs,
redeemScripts[inputIndex],
version=tx.version)
# we don't set meaningful outputAddress, amount and fees
# as we only care about the alternateEncoding==True branch
outputData = client_ledger.finalizeInput(
b'', 0, 0, changePath, bfh(rawTx))
outputData['outputData'] = txOutput
if outputData['confirmationNeeded']:
outputData['address'] = output
self.handler.finished()
# do the authenticate dialog and get pin:
pin = self.handler.get_auth(outputData,
client=client_electrum)
if not pin:
raise UserWarning()
self.handler.show_message(
_("Confirmed. Signing Transaction..."))
else:
# Sign input with the provided PIN
inputSignature = client_ledger.untrustedHashSign(
inputsPaths[inputIndex], pin, lockTime=tx.locktime)
inputSignature[0] = 0x30 # force for 1.4.9+
my_pubkey = inputs[inputIndex][4]
tx.add_signature_to_txin(
txin_idx=inputIndex,
signing_pubkey=my_pubkey.hex(),
sig=inputSignature.hex())
inputIndex = inputIndex + 1
firstTransaction = False
except UserWarning:
self.handler.show_error(_('Cancelled by user'))
return
except BTChipException as e:
if e.sw in (0x6985, 0x6d00): # cancelled by user
return
elif e.sw == 0x6982:
raise # pin lock. decorator will catch it
else:
self.logger.exception('')
self.give_error(e, True)
except BaseException as e:
self.logger.exception('')
self.give_error(e, True)
finally:
self.handler.finished()
def build_psbt(tx: Transaction, wallet: Abstract_Wallet):
# Render a PSBT file, for possible upload to Coldcard.
#
# TODO this should be part of Wallet object, or maybe Transaction?
if getattr(tx, 'raw_psbt', False):
_logger.info('PSBT cache hit')
return tx.raw_psbt
inputs = tx.inputs()
if 'prev_tx' not in inputs[0]:
# fetch info about inputs, if needed?
# - needed during export PSBT flow, not normal online signing
wallet.add_hw_info(tx)
# wallet.add_hw_info installs this attr
assert tx.output_info is not None, 'need data about outputs'
# Build a map of all pubkeys needed as derivation from master XFP, in PSBT binary format
# 1) binary version of the common subpath for all keys
# m/ => fingerprint LE32
# a/b/c => ints
#
# 2) all used keys in transaction:
# - for all inputs and outputs (when its change back)
# - for all keystores, if multisig
#
subkeys = {}
for ks in wallet.get_keystores():
# XFP + fixed prefix for this keystore
ks_prefix = packed_xfp_path_for_keystore(ks)
# all pubkeys needed for input signing
for xpubkey, derivation in ks.get_tx_derivations(tx).items():
pubkey = xpubkey_to_pubkey(xpubkey)
# assuming depth two, non-harded: change + index
aa, bb = derivation
assert 0 <= aa < 0x80000000 and 0 <= bb < 0x80000000
subkeys[bfh(pubkey)] = ks_prefix + pack('<II', aa, bb)
# all keys related to change outputs
for o in tx.outputs():
if o.address in tx.output_info:
# this address "is_mine" but might not be change (if I send funds to myself)
output_info = tx.output_info.get(o.address)
if not output_info.is_change:
continue
chg_path = output_info.address_index
assert chg_path[0] == 1 and len(chg_path) == 2, f"unexpected change path: {chg_path}"
pubkey = ks.derive_pubkey(True, chg_path[1])
subkeys[bfh(pubkey)] = ks_prefix + pack('<II', *chg_path)
for txin in inputs:
assert txin['type'] != 'coinbase', _("Coinbase not supported")
if txin['type'] in ['p2sh', 'p2wsh-p2sh', 'p2wsh']:
assert type(wallet) is Multisig_Wallet
# Construct PSBT from start to finish.
out_fd = io.BytesIO()
out_fd.write(b'psbt\xff')
def write_kv(ktype, val, key=b''):
# serialize helper: write w/ size and key byte
out_fd.write(my_var_int(1 + len(key)))
out_fd.write(bytes([ktype]) + key)
if isinstance(val, str):
val = bfh(val)
out_fd.write(my_var_int(len(val)))
out_fd.write(val)
# global section: just the unsigned txn
class CustomTXSerialization(Transaction):
@classmethod
def input_script(cls, txin, estimate_size=False):
return ''
unsigned = bfh(CustomTXSerialization(tx.serialize()).serialize_to_network(witness=False))
write_kv(PSBT_GLOBAL_UNSIGNED_TX, unsigned)
if type(wallet) is Multisig_Wallet:
# always put the xpubs into the PSBT, useful at least for checking
for xp, ks in zip(wallet.get_master_public_keys(), wallet.get_keystores()):
ks_prefix = packed_xfp_path_for_keystore(ks)
write_kv(PSBT_GLOBAL_XPUB, ks_prefix, DecodeBase58Check(xp))
# end globals section
out_fd.write(b'\x00')
# inputs section
for txin in inputs:
if Transaction.is_segwit_input(txin):
utxo = txin['prev_tx'].outputs()[txin['prevout_n']]
spendable = txin['prev_tx'].serialize_output(utxo)
write_kv(PSBT_IN_WITNESS_UTXO, spendable)
else:
write_kv(PSBT_IN_NON_WITNESS_UTXO, str(txin['prev_tx']))
pubkeys, x_pubkeys = tx.get_sorted_pubkeys(txin)
pubkeys = [bfh(k) for k in pubkeys]
if type(wallet) is Multisig_Wallet:
# always need a redeem script for multisig
scr = Transaction.get_preimage_script(txin)
if Transaction.is_segwit_input(txin):
# needed for both p2wsh-p2sh and p2wsh
write_kv(PSBT_IN_WITNESS_SCRIPT, bfh(scr))
else:
write_kv(PSBT_IN_REDEEM_SCRIPT, bfh(scr))
sigs = txin.get('signatures')
for pk_pos, (pubkey, x_pubkey) in enumerate(zip(pubkeys, x_pubkeys)):
if pubkey in subkeys:
# faster? case ... calculated above
write_kv(PSBT_IN_BIP32_DERIVATION, subkeys[pubkey], pubkey)
else:
# when an input is partly signed, tx.get_tx_derivations()
# doesn't include that keystore's value and yet we need it
# because we need to show a correct keypath...
assert x_pubkey[0:2] == 'ff', x_pubkey
for ks in wallet.get_keystores():
d = ks.get_pubkey_derivation(x_pubkey)
if d is not None:
ks_path = packed_xfp_path_for_keystore(ks, d)
write_kv(PSBT_IN_BIP32_DERIVATION, ks_path, pubkey)
break
else:
raise AssertionError("no keystore for: %s" % x_pubkey)
if txin['type'] == 'p2wpkh-p2sh':
assert len(pubkeys) == 1, 'can be only one redeem script per input'
pa = hash_160(pubkey)
assert len(pa) == 20
write_kv(PSBT_IN_REDEEM_SCRIPT, b'\x00\x14'+pa)
# optional? insert (partial) signatures that we already have
if sigs and sigs[pk_pos]:
write_kv(PSBT_IN_PARTIAL_SIG, bfh(sigs[pk_pos]), pubkey)
out_fd.write(b'\x00')
# outputs section
for o in tx.outputs():
# can be empty, but must be present, and helpful to show change inputs
# wallet.add_hw_info() adds some data about change outputs into tx.output_info
if o.address in tx.output_info:
# this address "is_mine" but might not be change (if I send funds to myself)
output_info = tx.output_info.get(o.address)
if output_info.is_change:
pubkeys = [bfh(i) for i in wallet.get_public_keys(o.address)]
# Add redeem/witness script?
if type(wallet) is Multisig_Wallet:
# always need a redeem script for multisig cases
scr = bfh(multisig_script([bh2u(i) for i in sorted(pubkeys)], wallet.m))
if output_info.script_type == 'p2wsh-p2sh':
write_kv(PSBT_OUT_WITNESS_SCRIPT, scr)
write_kv(PSBT_OUT_REDEEM_SCRIPT, b'\x00\x20' + sha256(scr))
elif output_info.script_type == 'p2wsh':
write_kv(PSBT_OUT_WITNESS_SCRIPT, scr)
elif output_info.script_type == 'p2sh':
write_kv(PSBT_OUT_REDEEM_SCRIPT, scr)
else:
raise ValueError(output_info.script_type)
elif output_info.script_type == 'p2wpkh-p2sh':
# need a redeem script when P2SH is used to wrap p2wpkh
assert len(pubkeys) == 1
pa = hash_160(pubkeys[0])
write_kv(PSBT_OUT_REDEEM_SCRIPT, b'\x00\x14' + pa)
# Document change output's bip32 derivation(s)
for pubkey in pubkeys:
sk = subkeys[pubkey]
write_kv(PSBT_OUT_BIP32_DERIVATION, sk, pubkey)
out_fd.write(b'\x00')
# capture for later use
tx.raw_psbt = out_fd.getvalue()
return tx.raw_psbt