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mirror of https://github.com/trezor/trezor-firmware.git synced 2024-11-25 17:09:44 +00:00
trezor-firmware/python/tools/deserialize_tx.py
2019-04-15 19:15:12 +02:00

85 lines
2.1 KiB
Python
Executable File

#!/usr/bin/env python3
import os
import sys
try:
import construct as c
except ImportError:
sys.stderr.write("This tool requires Construct. Install it with 'pip install Construct'.\n")
sys.exit(1)
from construct import this, len_
if os.isatty(sys.stdin.fileno()):
tx_hex = input("Enter transaction in hex format: ")
else:
tx_hex = sys.stdin.read().strip()
tx_bin = bytes.fromhex(tx_hex)
CompactUintStruct = c.Struct(
"base" / c.Int8ul,
"ext" / c.Switch(this.base, {0xfd: c.Int16ul, 0xfe: c.Int32ul, 0xff: c.Int64ul}),
)
class CompactUintAdapter(c.Adapter):
def _encode(self, obj, context, path):
if obj < 0xfd:
return {"base": obj}
if obj < 2 ** 16:
return {"base": 0xfd, "ext": obj}
if obj < 2 ** 32:
return {"base": 0xfe, "ext": obj}
if obj < 2 ** 64:
return {"base": 0xff, "ext": obj}
raise ValueError("Value too big for compact uint")
def _decode(self, obj, context, path):
return obj["ext"] or obj["base"]
class ConstFlag(c.Adapter):
def __init__(self, const):
self.const = const
super().__init__(c.Optional(c.Const(const)))
def _encode(self, obj, context, path):
return self.const if obj else None
def _decode(self, obj, context, path):
return obj is not None
CompactUint = CompactUintAdapter(CompactUintStruct)
TxInput = c.Struct(
"tx" / c.Bytes(32),
"index" / c.Int32ul,
# TODO coinbase tx
"script" / c.Prefixed(CompactUint, c.GreedyBytes),
"sequence" / c.Int32ul,
)
TxOutput = c.Struct(
"value" / c.Int64ul,
"pk_script" / c.Prefixed(CompactUint, c.GreedyBytes),
)
StackItem = c.Prefixed(CompactUint, c.GreedyBytes)
TxInputWitness = c.PrefixedArray(CompactUint, StackItem)
Transaction = c.Struct(
"version" / c.Int32ul,
"segwit" / ConstFlag(b"\x00\x01"),
"inputs" / c.PrefixedArray(CompactUint, TxInput),
"outputs" / c.PrefixedArray(CompactUint, TxOutput),
"witness" / c.If(this.segwit, TxInputWitness[len_(this.inputs)]),
"lock_time" / c.Int32ul,
c.Terminated,
)
print(Transaction.parse(tx_bin))