def input_script_multisig( multisig: MultisigRedeemScriptType, signature: bytes, signature_index: int, sighash: int, ): signatures = multisig.signatures # other signatures if len(signatures[signature_index]) > 0: raise ScriptsError("Invalid multisig parameters") signatures[signature_index] = signature # our signature w = bytearray() # Starts with OP_FALSE because of an old OP_CHECKMULTISIG bug, which # consumes one additional item on the stack: # https://bitcoin.org/en/developer-guide#standard-transactions w.append(0x00) for s in signatures: if len(s): append_signature(w, s, sighash) # redeem script pubkeys = multisig_get_pubkeys(multisig) redeem_script = output_script_multisig(pubkeys, multisig.m) write_op_push(w, len(redeem_script)) write_bytes(w, redeem_script) return w
def multisig_fingerprint(multisig: MultisigRedeemScriptType) -> bytes: pubkeys = multisig.pubkeys m = multisig.m n = len(pubkeys) if n < 1 or n > 15 or m < 1 or m > 15: raise MultisigError(FailureType.DataError, "Invalid multisig parameters") for hd in pubkeys: d = hd.node if len(d.public_key) != 33 or len(d.chain_code) != 32: raise MultisigError(FailureType.DataError, "Invalid multisig parameters") # casting to bytes(), sorting on bytearray() is not supported in MicroPython pubkeys = sorted(pubkeys, key=lambda hd: bytes(hd.node.public_key)) h = HashWriter(sha256) write_uint32(h, m) write_uint32(h, n) for hd in pubkeys: d = hd.node write_uint32(h, d.depth) write_uint32(h, d.fingerprint) write_uint32(h, d.child_num) write_bytes(h, d.chain_code) write_bytes(h, d.public_key) return h.get_digest()
def preimage_hash(self, coin: CoinInfo, tx: SignTx, txi: TxInputType, pubkeyhash: bytes, sighash: int) -> bytes: h_preimage = HashWriter( blake2b, b'', 32, b'ZcashSigHash\x19\x1b\xa8\x5b') # BRANCH_ID = 0x5ba81b19 assert tx.overwintered write_uint32(h_preimage, tx.version | OVERWINTERED) # 1. nVersion | fOverwintered write_uint32(h_preimage, coin.version_group_id) # 2. nVersionGroupId write_bytes(h_preimage, bytearray(self.get_prevouts_hash())) # 3. hashPrevouts write_bytes(h_preimage, bytearray(self.get_sequence_hash())) # 4. hashSequence write_bytes(h_preimage, bytearray(self.get_outputs_hash())) # 5. hashOutputs write_bytes(h_preimage, b'\x00' * 32) # 6. hashJoinSplits write_uint32(h_preimage, tx.lock_time) # 7. nLockTime write_uint32(h_preimage, tx.expiry) # 8. expiryHeight write_uint32(h_preimage, sighash) # 9. nHashType write_bytes_rev(h_preimage, txi.prev_hash) # 10a. outpoint write_uint32(h_preimage, txi.prev_index) script_code = self.derive_script_code(txi, pubkeyhash) # 10b. scriptCode write_varint(h_preimage, len(script_code)) write_bytes(h_preimage, script_code) write_uint64(h_preimage, txi.amount) # 10c. value write_uint32(h_preimage, txi.sequence) # 10d. nSequence return get_tx_hash(h_preimage)
def witness_p2wsh( multisig: MultisigRedeemScriptType, signature: bytes, signature_index: int, sighash: int, ): signatures = multisig.signatures # other signatures if len(signatures[signature_index]) > 0: raise ScriptsError("Invalid multisig parameters") signatures[signature_index] = signature # our signature # filter empty signatures = [s for s in multisig.signatures if len(s) > 0] # witness program + signatures + redeem script num_of_witness_items = 1 + len(signatures) + 1 w = bytearray() write_varint(w, num_of_witness_items) write_varint(w, 0) # version 0 witness program for s in signatures: append_signature(w, s, sighash) # size of the witness included # redeem script pubkeys = multisig_get_pubkeys(multisig) redeem_script = output_script_multisig(pubkeys, multisig.m) write_varint(w, len(redeem_script)) write_bytes(w, redeem_script) return w
def input_script_p2wpkh_in_p2sh(pubkeyhash: bytes) -> bytearray: # 16 00 14 <pubkeyhash> # Signature is moved to the witness. w = empty_bytearray(3 + len(pubkeyhash)) w.append(0x16) # length of the data w.append(0x00) # witness version byte w.append(0x14) # P2WPKH witness program (pub key hash length) write_bytes(w, pubkeyhash) # pub key hash return w
def output_script_native_p2wpkh_or_p2wsh(witprog: bytes) -> bytearray: # Either: # 00 14 <20-byte-key-hash> # 00 20 <32-byte-script-hash> w = empty_bytearray(3 + len(witprog)) w.append(0x00) # witness version byte w.append(len(witprog)) # pub key hash length is 20 (P2WPKH) or 32 (P2WSH) bytes write_bytes(w, witprog) # pub key hash return w
def input_script_p2wsh_in_p2sh(script_hash: bytes) -> bytearray: # 22 00 20 <redeem script hash> # Signature is moved to the witness. if len(script_hash) != 32: raise ScriptsError("Redeem script hash should be 32 bytes long") w = empty_bytearray(3 + len(script_hash)) w.append(0x22) # length of the data w.append(0x00) # witness version byte w.append(0x20) # P2WSH witness program (redeem script hash length) write_bytes(w, script_hash) return w
def preimage_hash( self, coin: CoinInfo, tx: SignTx, txi: TxInputType, pubkeyhash: bytes, sighash: int, ) -> bytes: h_preimage = HashWriter(sha256) assert not tx.overwintered write_uint32(h_preimage, tx.version) # nVersion write_bytes(h_preimage, bytearray(self.get_prevouts_hash(coin))) # hashPrevouts write_bytes(h_preimage, bytearray(self.get_sequence_hash(coin))) # hashSequence write_bytes_rev(h_preimage, txi.prev_hash) # outpoint write_uint32(h_preimage, txi.prev_index) # outpoint script_code = self.derive_script_code(txi, pubkeyhash) # scriptCode write_varint(h_preimage, len(script_code)) write_bytes(h_preimage, script_code) write_uint64(h_preimage, txi.amount) # amount write_uint32(h_preimage, txi.sequence) # nSequence write_bytes(h_preimage, bytearray(self.get_outputs_hash(coin))) # hashOutputs write_uint32(h_preimage, tx.lock_time) # nLockTime write_uint32(h_preimage, sighash) # nHashType return get_tx_hash(h_preimage, double=coin.sign_hash_double)
def preimage_hash( self, coin: CoinInfo, tx: SignTx, txi: TxInputType, pubkeyhash: bytes, sighash: int, ) -> bytes: h_preimage = HashWriter( blake2b( outlen=32, personal=b"ZcashSigHash" + struct.pack("<I", self.branch_id) ) ) ensure(tx.overwintered) ensure(tx.version == 3) write_uint32( h_preimage, tx.version | OVERWINTERED ) # 1. nVersion | fOverwintered write_uint32(h_preimage, tx.version_group_id) # 2. nVersionGroupId write_bytes(h_preimage, bytearray(self.get_prevouts_hash())) # 3. hashPrevouts write_bytes(h_preimage, bytearray(self.get_sequence_hash())) # 4. hashSequence write_bytes(h_preimage, bytearray(self.get_outputs_hash())) # 5. hashOutputs write_bytes(h_preimage, b"\x00" * 32) # 6. hashJoinSplits write_uint32(h_preimage, tx.lock_time) # 7. nLockTime write_uint32(h_preimage, tx.expiry) # 8. expiryHeight write_uint32(h_preimage, sighash) # 9. nHashType write_bytes_reversed(h_preimage, txi.prev_hash) # 10a. outpoint write_uint32(h_preimage, txi.prev_index) script_code = derive_script_code(txi, pubkeyhash) # 10b. scriptCode write_varint(h_preimage, len(script_code)) write_bytes(h_preimage, script_code) write_uint64(h_preimage, txi.amount) # 10c. value write_uint32(h_preimage, txi.sequence) # 10d. nSequence return get_tx_hash(h_preimage)
def append_pubkey(w: bytearray, pubkey: bytes) -> bytearray: write_op_push(w, len(pubkey)) write_bytes(w, pubkey) return w
def append_signature(w: bytearray, signature: bytes, sighash: int) -> bytearray: write_op_push(w, len(signature) + 1) write_bytes(w, signature) w.append(sighash) return w
def preimage_hash( self, coin: CoinInfo, tx: SignTx, txi: TxInputType, pubkeyhash: bytes, sighash: int, ) -> bytes: h_preimage = HashWriter( blake2b(outlen=32, personal=b"ZcashSigHash\xbb\x09\xb8\x76") ) # BRANCH_ID = 0x76b809bb / Sapling ensure(tx.overwintered) ensure(tx.version == 4) write_uint32(h_preimage, tx.version | OVERWINTERED) # 1. nVersion | fOverwintered write_uint32(h_preimage, tx.version_group_id) # 2. nVersionGroupId write_bytes(h_preimage, bytearray(self.get_prevouts_hash())) # 3. hashPrevouts write_bytes(h_preimage, bytearray(self.get_sequence_hash())) # 4. hashSequence write_bytes(h_preimage, bytearray(self.get_outputs_hash())) # 5. hashOutputs write_bytes(h_preimage, b"\x00" * 32) # 6. hashJoinSplits write_bytes(h_preimage, b"\x00" * 32) # 7. hashShieldedSpends write_bytes(h_preimage, b"\x00" * 32) # 8. hashShieldedOutputs write_uint32(h_preimage, tx.lock_time - self.hash_lock_offset) # 9. nLockTime write_uint32(h_preimage, tx.expiry) # 10. expiryHeight write_uint64(h_preimage, 0) # 11. valueBalance write_uint32(h_preimage, sighash) # 12. nHashType write_bytes_reversed(h_preimage, txi.prev_hash) # 13a. outpoint write_uint32(h_preimage, txi.prev_index) script_code = derive_script_code(txi, pubkeyhash) # 13b. scriptCode write_varint(h_preimage, len(script_code)) write_bytes(h_preimage, script_code) write_uint64(h_preimage, txi.amount) # 13c. value write_uint32(h_preimage, txi.sequence) # 13d. nSequence return get_tx_hash(h_preimage)
async def get_prevtx_output_value(coin: coininfo.CoinInfo, tx_req: TxRequest, prev_hash: bytes, prev_index: int) -> int: total_out = 0 # sum of output amounts # STAGE_REQUEST_2_PREV_META tx = await helpers.request_tx_meta(tx_req, prev_hash) if coin.decred: txh = utils.HashWriter(blake256()) else: txh = utils.HashWriter(sha256()) if tx.overwintered: writers.write_uint32(txh, tx.version | zcash.OVERWINTERED) # nVersion | fOverwintered writers.write_uint32(txh, tx.version_group_id) # nVersionGroupId elif coin.decred: writers.write_uint32(txh, tx.version | decred.DECRED_SERIALIZE_NO_WITNESS) else: writers.write_uint32(txh, tx.version) # nVersion if tx.timestamp: writers.write_uint32(txh, tx.timestamp) writers.write_varint(txh, tx.inputs_cnt) for i in range(tx.inputs_cnt): # STAGE_REQUEST_2_PREV_INPUT txi = await helpers.request_tx_input(tx_req, i, prev_hash) if coin.decred: writers.write_tx_input_decred(txh, txi) else: writers.write_tx_input(txh, txi) writers.write_varint(txh, tx.outputs_cnt) for o in range(tx.outputs_cnt): # STAGE_REQUEST_2_PREV_OUTPUT txo_bin = await helpers.request_tx_output(tx_req, o, prev_hash) writers.write_tx_output(txh, txo_bin) if o == prev_index: total_out += txo_bin.amount if (coin.decred and txo_bin.decred_script_version is not None and txo_bin.decred_script_version != 0): raise SigningError( FailureType.ProcessError, "Cannot use utxo that has script_version != 0", ) writers.write_uint32(txh, tx.lock_time) if tx.overwintered or coin.decred: writers.write_uint32(txh, tx.expiry) ofs = 0 while ofs < tx.extra_data_len: size = min(1024, tx.extra_data_len - ofs) data = await helpers.request_tx_extra_data(tx_req, ofs, size, prev_hash) writers.write_bytes(txh, data) ofs += len(data) if (writers.get_tx_hash(txh, double=coin.sign_hash_double, reverse=True) != prev_hash): raise SigningError(FailureType.ProcessError, "Encountered invalid prev_hash") return total_out
async def check_tx_fee(tx: SignTx, keychain: seed.Keychain): coin = coins.by_name(tx.coin_name) # h_first is used to make sure the inputs and outputs streamed in Phase 1 # are the same as in Phase 2. it is thus not required to fully hash the # tx, as the SignTx info is streamed only once h_first = utils.HashWriter(sha256()) # not a real tx hash if coin.decred: hash143 = decred.DecredPrefixHasher( tx) # pseudo BIP-0143 prefix hashing tx_ser = TxRequestSerializedType() elif tx.overwintered: if tx.version == 3: hash143 = zcash.Zip143() # ZIP-0143 transaction hashing elif tx.version == 4: hash143 = zcash.Zip243() # ZIP-0243 transaction hashing else: raise SigningError( FailureType.DataError, "Unsupported version for overwintered transaction", ) else: hash143 = segwit_bip143.Bip143() # BIP-0143 transaction hashing multifp = multisig.MultisigFingerprint( ) # control checksum of multisig inputs weight = tx_weight.TxWeightCalculator(tx.inputs_count, tx.outputs_count) total_in = 0 # sum of input amounts segwit_in = 0 # sum of segwit input amounts total_out = 0 # sum of output amounts change_out = 0 # change output amount wallet_path = [] # common prefix of input paths segwit = {} # dict of booleans stating if input is segwit # output structures txo_bin = TxOutputBinType() tx_req = TxRequest() tx_req.details = TxRequestDetailsType() for i in range(tx.inputs_count): progress.advance() # STAGE_REQUEST_1_INPUT txi = await helpers.request_tx_input(tx_req, i) wallet_path = input_extract_wallet_path(txi, wallet_path) writers.write_tx_input_check(h_first, txi) weight.add_input(txi) hash143.add_prevouts( txi) # all inputs are included (non-segwit as well) hash143.add_sequence(txi) if not addresses.validate_full_path(txi.address_n, coin, txi.script_type): await helpers.confirm_foreign_address(txi.address_n) if txi.multisig: multifp.add(txi.multisig) if txi.script_type in ( InputScriptType.SPENDWITNESS, InputScriptType.SPENDP2SHWITNESS, ): if not coin.segwit: raise SigningError(FailureType.DataError, "Segwit not enabled on this coin") if not txi.amount: raise SigningError(FailureType.DataError, "Segwit input without amount") segwit[i] = True segwit_in += txi.amount total_in += txi.amount elif txi.script_type in ( InputScriptType.SPENDADDRESS, InputScriptType.SPENDMULTISIG, ): if coin.force_bip143 or tx.overwintered: if not txi.amount: raise SigningError(FailureType.DataError, "Expected input with amount") segwit[i] = False segwit_in += txi.amount total_in += txi.amount else: segwit[i] = False total_in += await get_prevtx_output_value( coin, tx_req, txi.prev_hash, txi.prev_index) else: raise SigningError(FailureType.DataError, "Wrong input script type") if coin.decred: w_txi = writers.empty_bytearray(8 if i == 0 else 0 + 9 + len(txi.prev_hash)) if i == 0: # serializing first input => prepend headers writers.write_bytes(w_txi, get_tx_header(coin, tx)) writers.write_tx_input_decred(w_txi, txi) tx_ser.serialized_tx = w_txi tx_req.serialized = tx_ser if coin.decred: hash143.add_output_count(tx) for o in range(tx.outputs_count): # STAGE_REQUEST_3_OUTPUT txo = await helpers.request_tx_output(tx_req, o) txo_bin.amount = txo.amount txo_bin.script_pubkey = output_derive_script(txo, coin, keychain) weight.add_output(txo_bin.script_pubkey) if change_out == 0 and output_is_change(txo, wallet_path, segwit_in, multifp): # output is change and does not need confirmation change_out = txo.amount elif not await helpers.confirm_output(txo, coin): raise SigningError(FailureType.ActionCancelled, "Output cancelled") if coin.decred: if txo.decred_script_version is not None and txo.decred_script_version != 0: raise SigningError( FailureType.ActionCancelled, "Cannot send to output with script version != 0", ) txo_bin.decred_script_version = txo.decred_script_version w_txo_bin = writers.empty_bytearray(4 + 8 + 2 + 4 + len(txo_bin.script_pubkey)) if o == 0: # serializing first output => prepend outputs count writers.write_varint(w_txo_bin, tx.outputs_count) writers.write_tx_output(w_txo_bin, txo_bin) tx_ser.serialized_tx = w_txo_bin tx_req.serialized = tx_ser hash143.set_last_output_bytes(w_txo_bin) writers.write_tx_output(h_first, txo_bin) hash143.add_output(txo_bin) total_out += txo_bin.amount fee = total_in - total_out if fee < 0: raise SigningError(FailureType.NotEnoughFunds, "Not enough funds") # fee > (coin.maxfee per byte * tx size) if fee > (coin.maxfee_kb / 1000) * (weight.get_total() / 4): if not await helpers.confirm_feeoverthreshold(fee, coin): raise SigningError(FailureType.ActionCancelled, "Signing cancelled") if not await helpers.confirm_total(total_in - change_out, fee, coin): raise SigningError(FailureType.ActionCancelled, "Total cancelled") if coin.decred: hash143.add_locktime_expiry(tx) return h_first, hash143, segwit, total_in, wallet_path
async def sign_tx(tx: SignTx, keychain: seed.Keychain): tx = helpers.sanitize_sign_tx(tx) progress.init(tx.inputs_count, tx.outputs_count) # Phase 1 h_first, hash143, segwit, authorized_in, wallet_path = await check_tx_fee( tx, keychain) # Phase 2 # - sign inputs # - check that nothing changed coin = coins.by_name(tx.coin_name) tx_ser = TxRequestSerializedType() txo_bin = TxOutputBinType() tx_req = TxRequest() tx_req.details = TxRequestDetailsType() tx_req.serialized = None if coin.decred: prefix_hash = hash143.prefix_hash() for i_sign in range(tx.inputs_count): progress.advance() txi_sign = None key_sign = None key_sign_pub = None if segwit[i_sign]: # STAGE_REQUEST_SEGWIT_INPUT txi_sign = await helpers.request_tx_input(tx_req, i_sign) if not input_is_segwit(txi_sign): raise SigningError(FailureType.ProcessError, "Transaction has changed during signing") input_check_wallet_path(txi_sign, wallet_path) key_sign = keychain.derive(txi_sign.address_n, coin.curve_name) key_sign_pub = key_sign.public_key() txi_sign.script_sig = input_derive_script(coin, txi_sign, key_sign_pub) w_txi = writers.empty_bytearray(7 + len(txi_sign.prev_hash) + 4 + len(txi_sign.script_sig) + 4) if i_sign == 0: # serializing first input => prepend headers writers.write_bytes(w_txi, get_tx_header(coin, tx, True)) writers.write_tx_input(w_txi, txi_sign) tx_ser.serialized_tx = w_txi tx_req.serialized = tx_ser elif coin.force_bip143 or tx.overwintered: # STAGE_REQUEST_SEGWIT_INPUT txi_sign = await helpers.request_tx_input(tx_req, i_sign) input_check_wallet_path(txi_sign, wallet_path) is_bip143 = (txi_sign.script_type == InputScriptType.SPENDADDRESS or txi_sign.script_type == InputScriptType.SPENDMULTISIG) if not is_bip143 or txi_sign.amount > authorized_in: raise SigningError(FailureType.ProcessError, "Transaction has changed during signing") authorized_in -= txi_sign.amount key_sign = keychain.derive(txi_sign.address_n, coin.curve_name) key_sign_pub = key_sign.public_key() hash143_hash = hash143.preimage_hash( coin, tx, txi_sign, addresses.ecdsa_hash_pubkey(key_sign_pub, coin), get_hash_type(coin), ) # if multisig, check if signing with a key that is included in multisig if txi_sign.multisig: multisig.multisig_pubkey_index(txi_sign.multisig, key_sign_pub) signature = ecdsa_sign(key_sign, hash143_hash) tx_ser.signature_index = i_sign tx_ser.signature = signature # serialize input with correct signature txi_sign.script_sig = input_derive_script(coin, txi_sign, key_sign_pub, signature) w_txi_sign = writers.empty_bytearray(5 + len(txi_sign.prev_hash) + 4 + len(txi_sign.script_sig) + 4) if i_sign == 0: # serializing first input => prepend headers writers.write_bytes(w_txi_sign, get_tx_header(coin, tx)) writers.write_tx_input(w_txi_sign, txi_sign) tx_ser.serialized_tx = w_txi_sign tx_req.serialized = tx_ser elif coin.decred: txi_sign = await helpers.request_tx_input(tx_req, i_sign) input_check_wallet_path(txi_sign, wallet_path) key_sign = keychain.derive(txi_sign.address_n, coin.curve_name) key_sign_pub = key_sign.public_key() if txi_sign.script_type == InputScriptType.SPENDMULTISIG: prev_pkscript = scripts.output_script_multisig( multisig.multisig_get_pubkeys(txi_sign.multisig), txi_sign.multisig.m, ) elif txi_sign.script_type == InputScriptType.SPENDADDRESS: prev_pkscript = scripts.output_script_p2pkh( addresses.ecdsa_hash_pubkey(key_sign_pub, coin)) else: raise ValueError("Unknown input script type") h_witness = utils.HashWriter(blake256()) writers.write_uint32( h_witness, tx.version | decred.DECRED_SERIALIZE_WITNESS_SIGNING) writers.write_varint(h_witness, tx.inputs_count) for ii in range(tx.inputs_count): if ii == i_sign: writers.write_varint(h_witness, len(prev_pkscript)) writers.write_bytes(h_witness, prev_pkscript) else: writers.write_varint(h_witness, 0) witness_hash = writers.get_tx_hash(h_witness, double=coin.sign_hash_double, reverse=False) h_sign = utils.HashWriter(blake256()) writers.write_uint32(h_sign, decred.DECRED_SIGHASHALL) writers.write_bytes(h_sign, prefix_hash) writers.write_bytes(h_sign, witness_hash) sig_hash = writers.get_tx_hash(h_sign, double=coin.sign_hash_double) signature = ecdsa_sign(key_sign, sig_hash) tx_ser.signature_index = i_sign tx_ser.signature = signature # serialize input with correct signature txi_sign.script_sig = input_derive_script(coin, txi_sign, key_sign_pub, signature) w_txi_sign = writers.empty_bytearray( 8 + 4 + len(hash143.get_last_output_bytes()) if i_sign == 0 else 0 + 16 + 4 + len(txi_sign.script_sig)) if i_sign == 0: writers.write_bytes(w_txi_sign, hash143.get_last_output_bytes()) writers.write_uint32(w_txi_sign, tx.lock_time) writers.write_uint32(w_txi_sign, tx.expiry) writers.write_varint(w_txi_sign, tx.inputs_count) writers.write_tx_input_decred_witness(w_txi_sign, txi_sign) tx_ser.serialized_tx = w_txi_sign tx_req.serialized = tx_ser else: # hash of what we are signing with this input h_sign = utils.HashWriter(sha256()) # same as h_first, checked before signing the digest h_second = utils.HashWriter(sha256()) if tx.overwintered: writers.write_uint32( h_sign, tx.version | zcash.OVERWINTERED) # nVersion | fOverwintered writers.write_uint32(h_sign, tx.version_group_id) # nVersionGroupId else: writers.write_uint32(h_sign, tx.version) # nVersion if tx.timestamp: writers.write_uint32(h_sign, tx.timestamp) writers.write_varint(h_sign, tx.inputs_count) for i in range(tx.inputs_count): # STAGE_REQUEST_4_INPUT txi = await helpers.request_tx_input(tx_req, i) input_check_wallet_path(txi, wallet_path) writers.write_tx_input_check(h_second, txi) if i == i_sign: txi_sign = txi key_sign = keychain.derive(txi.address_n, coin.curve_name) key_sign_pub = key_sign.public_key() # for the signing process the script_sig is equal # to the previous tx's scriptPubKey (P2PKH) or a redeem script (P2SH) if txi_sign.script_type == InputScriptType.SPENDMULTISIG: txi_sign.script_sig = scripts.output_script_multisig( multisig.multisig_get_pubkeys(txi_sign.multisig), txi_sign.multisig.m, ) elif txi_sign.script_type == InputScriptType.SPENDADDRESS: txi_sign.script_sig = scripts.output_script_p2pkh( addresses.ecdsa_hash_pubkey(key_sign_pub, coin)) if coin.bip115: txi_sign.script_sig += scripts.script_replay_protection_bip115( txi_sign.prev_block_hash_bip115, txi_sign.prev_block_height_bip115, ) else: raise SigningError(FailureType.ProcessError, "Unknown transaction type") else: txi.script_sig = bytes() writers.write_tx_input(h_sign, txi) writers.write_varint(h_sign, tx.outputs_count) for o in range(tx.outputs_count): # STAGE_REQUEST_4_OUTPUT txo = await helpers.request_tx_output(tx_req, o) txo_bin.amount = txo.amount txo_bin.script_pubkey = output_derive_script( txo, coin, keychain) writers.write_tx_output(h_second, txo_bin) writers.write_tx_output(h_sign, txo_bin) writers.write_uint32(h_sign, tx.lock_time) if tx.overwintered: writers.write_uint32(h_sign, tx.expiry) # expiryHeight writers.write_varint(h_sign, 0) # nJoinSplit writers.write_uint32(h_sign, get_hash_type(coin)) # check the control digests if writers.get_tx_hash(h_first, False) != writers.get_tx_hash(h_second): raise SigningError(FailureType.ProcessError, "Transaction has changed during signing") # if multisig, check if signing with a key that is included in multisig if txi_sign.multisig: multisig.multisig_pubkey_index(txi_sign.multisig, key_sign_pub) # compute the signature from the tx digest signature = ecdsa_sign( key_sign, writers.get_tx_hash(h_sign, double=coin.sign_hash_double)) tx_ser.signature_index = i_sign tx_ser.signature = signature # serialize input with correct signature txi_sign.script_sig = input_derive_script(coin, txi_sign, key_sign_pub, signature) w_txi_sign = writers.empty_bytearray(5 + len(txi_sign.prev_hash) + 4 + len(txi_sign.script_sig) + 4) if i_sign == 0: # serializing first input => prepend headers writers.write_bytes(w_txi_sign, get_tx_header(coin, tx)) writers.write_tx_input(w_txi_sign, txi_sign) tx_ser.serialized_tx = w_txi_sign tx_req.serialized = tx_ser if coin.decred: return await helpers.request_tx_finish(tx_req) for o in range(tx.outputs_count): progress.advance() # STAGE_REQUEST_5_OUTPUT txo = await helpers.request_tx_output(tx_req, o) txo_bin.amount = txo.amount txo_bin.script_pubkey = output_derive_script(txo, coin, keychain) # serialize output w_txo_bin = writers.empty_bytearray(5 + 8 + 5 + len(txo_bin.script_pubkey) + 4) if o == 0: # serializing first output => prepend outputs count writers.write_varint(w_txo_bin, tx.outputs_count) writers.write_tx_output(w_txo_bin, txo_bin) tx_ser.signature_index = None tx_ser.signature = None tx_ser.serialized_tx = w_txo_bin tx_req.serialized = tx_ser any_segwit = True in segwit.values() for i in range(tx.inputs_count): progress.advance() if segwit[i]: # STAGE_REQUEST_SEGWIT_WITNESS txi = await helpers.request_tx_input(tx_req, i) input_check_wallet_path(txi, wallet_path) if not input_is_segwit(txi) or txi.amount > authorized_in: raise SigningError(FailureType.ProcessError, "Transaction has changed during signing") authorized_in -= txi.amount key_sign = keychain.derive(txi.address_n, coin.curve_name) key_sign_pub = key_sign.public_key() hash143_hash = hash143.preimage_hash( coin, tx, txi, addresses.ecdsa_hash_pubkey(key_sign_pub, coin), get_hash_type(coin), ) signature = ecdsa_sign(key_sign, hash143_hash) if txi.multisig: # find out place of our signature based on the pubkey signature_index = multisig.multisig_pubkey_index( txi.multisig, key_sign_pub) witness = scripts.witness_p2wsh(txi.multisig, signature, signature_index, get_hash_type(coin)) else: witness = scripts.witness_p2wpkh(signature, key_sign_pub, get_hash_type(coin)) tx_ser.serialized_tx = witness tx_ser.signature_index = i tx_ser.signature = signature elif any_segwit: tx_ser.serialized_tx = bytearray( 1) # empty witness for non-segwit inputs tx_ser.signature_index = None tx_ser.signature = None tx_req.serialized = tx_ser writers.write_uint32(tx_ser.serialized_tx, tx.lock_time) if tx.overwintered: if tx.version == 3: writers.write_uint32(tx_ser.serialized_tx, tx.expiry) # expiryHeight writers.write_varint(tx_ser.serialized_tx, 0) # nJoinSplit elif tx.version == 4: writers.write_uint32(tx_ser.serialized_tx, tx.expiry) # expiryHeight writers.write_uint64(tx_ser.serialized_tx, 0) # valueBalance writers.write_varint(tx_ser.serialized_tx, 0) # nShieldedSpend writers.write_varint(tx_ser.serialized_tx, 0) # nShieldedOutput writers.write_varint(tx_ser.serialized_tx, 0) # nJoinSplit else: raise SigningError( FailureType.DataError, "Unsupported version for overwintered transaction", ) await helpers.request_tx_finish(tx_req)