reverted transactions.py

Author: Rasesh2005

bitcoinutils/transactions.py

@@ -12,7 +12,7 @@
 import math
 import hashlib
 import struct
-from typing import Optional
+from typing import Optional, Union
 
 from bitcoinutils.constants import (
     DEFAULT_TX_SEQUENCE,
@@ -141,7 +141,7 @@ def __repr__(self):
         return self.__str__()
 
     @staticmethod
-    def from_raw(txinputrawhex: str, cursor: int = 0, has_segwit: bool = False):
+    def from_raw(txinputrawhex: Union[str, bytes], cursor: int = 0, has_segwit: bool = False):
         """
         Imports a TxInput from a Transaction's hexadecimal data
 
@@ -154,7 +154,12 @@ def from_raw(txinputrawhex: str, cursor: int = 0, has_segwit: bool = False):
         has_segwit : boolean
             Is the Tx Input segwit or not
         """
-        txinputraw = h_to_b(txinputrawhex)
+        if isinstance(txinputrawhex, str):
+            txinputraw = h_to_b(txinputrawhex)
+        elif isinstance(txinputrawhex, bytes):
+            txinputraw = txinputrawhex
+        else:
+            raise TypeError("Input must be a hexadecimal string or bytes")
 
         # Unpack transaction ID (hash) in bytes and output index
         txid, vout = struct.unpack_from('<32sI', txinputraw, cursor)
@@ -286,7 +291,7 @@ def to_bytes(self) -> bytes:
         return data
 
     @staticmethod
-    def from_raw(txoutputrawhex: str, cursor: int = 0, has_segwit: bool = False):
+    def from_raw(txoutputrawhex: Union[str, bytes], cursor: int = 0, has_segwit: bool = False):
         """
         Imports a TxOutput from a Transaction's hexadecimal data
 
@@ -299,7 +304,13 @@ def from_raw(txoutputrawhex: str, cursor: int = 0, has_segwit: bool = False):
         has_segwit : boolean
             Is the Tx Output segwit or not
         """
-        txoutputraw = h_to_b(txoutputrawhex)
+        if isinstance(txoutputrawhex, str):
+            txoutputraw = h_to_b(txoutputrawhex)
+        elif isinstance(txoutputrawhex, bytes):
+            txoutputraw = txoutputrawhex
+        else:
+            raise TypeError("Input must be a hexadecimal string or bytes")
+        
 
         # Unpack the amount of the TxOutput directly in bytes
         amount_format = "<Q"  # Little-endian unsigned long long (8 bytes)
@@ -526,7 +537,7 @@ def __init__(
         self.version = version
 
     @staticmethod
-    def from_raw(rawtxhex: str):
+    def from_raw(rawtxhex: Union[str, bytes]):
         """
         Imports a Transaction from hexadecimal data.
 
@@ -535,7 +546,13 @@ def from_raw(rawtxhex: str):
         rawtxhex : string (hex)
             The hexadecimal raw string of the Transaction.
         """
-        rawtx = h_to_b(rawtxhex)
+        if isinstance(rawtxhex, str):
+            rawtx = h_to_b(rawtxhex)
+        elif isinstance(rawtxhex, bytes):
+            rawtx = rawtxhex
+        else:
+            raise TypeError("Input must be a hexadecimal string or bytes")
+        
 
         # Read version (4 bytes)
         version = rawtx[0:4]
@@ -567,9 +584,11 @@ def from_raw(rawtxhex: str):
             output, cursor = TxOutput.from_raw(rawtx.hex(), cursor, has_segwit)
             outputs.append(output)
 
-        # Handle witnesses if SegWit is enabled
+        # Handle witnesses if SegWit is enabled and if they are present i.e. if
+        # remaining payload length is greater than last tx field length (locktime)
+        has_witness_field = True if len(rawtx) - cursor > 4 else False
         witnesses = []
-        if has_segwit:
+        if has_segwit and has_witness_field:
             for _ in range(n_inputs):
                 n_items, size = parse_compact_size(rawtx[cursor:])
                 cursor += size
@@ -652,12 +671,13 @@ def get_transaction_digest(
         for txin in tmp_tx.inputs:
             txin.script_sig = Script([])
 
-        # If there are OP_CODESEPARATORs in the script, we need to remove them
-        # for the signature hash calculation
-        if "OP_CODESEPARATOR" in script.script:
-            # Create a new script without OP_CODESEPARATORs
-            filtered_script_elements = [element for element in script.script if element != "OP_CODESEPARATOR"]
-            script = Script(filtered_script_elements)
+        #
+        # TODO Deal with (delete?) script's OP_CODESEPARATORs, if any
+        # Very early versions of Bitcoin were using a different design for
+        # scripts that were flawed. OP_CODESEPARATOR has no purpose currently
+        # but we could not delete it for compatibility purposes. If it exists
+        # in a script it needs to be removed.
+        #
 
         # the temporary transaction's scriptSig needs to be set to the
         # scriptPubKey of the UTXO we are trying to spend - this is required to
@@ -843,6 +863,7 @@ def get_transaction_segwit_digest(
         return hashlib.sha256(hashlib.sha256(tx_for_signing).digest()).digest()
 
     # TODO Update doc with TAPROOT_SIGHASH_ALL
+    # clean prints after finishing other sighashes
     def get_transaction_taproot_digest(
         self,
         txin_index: int,
@@ -859,11 +880,11 @@ def get_transaction_taproot_digest(
         And: https://github.com/bitcoin/bitcoin/blob/b5f33ac1f82aea290b4653af36ac2ad1bf1cce7b/test/functional/test_framework/script.py
 
              |  SIGHASH types (see constants.py):
-             |      TAPROOT_SIGHASH_ALL (0x00) - signs all inputs and outputs (default)
-             |      SIGHASH_ALL (0x01) - signs all inputs and outputs
-             |      SIGHASH_NONE (0x02) - signs all of the inputs
-             |      SIGHASH_SINGLE (0x03) - signs all inputs but only txin_index output
-             |      SIGHASH_ANYONECANPAY (0x80) (only combined with one of the above)
+             |      TAPROOT_SIGHASH_ALL - signs all inputs and outputs (default)
+             |      SIGHASH_ALL - signs all inputs and outputs
+             |      SIGHASH_NONE - signs all of the inputs
+             |      SIGHASH_SINGLE - signs all inputs but only txin_index output
+             |      SIGHASH_ANYONECANPAY (only combined with one of the above)
              |      - with ALL - signs all outputs but only txin_index input
              |      - with NONE - signs only the txin_index input
              |      - with SINGLE - signs txin_index input and output
@@ -886,6 +907,10 @@ def get_transaction_taproot_digest(
                  The type of the signature hash to be created
         """
 
+        # clone transaction to modify without messing up the real transaction
+        # tmp_tx is not really used for its to_bytes() here
+        # TODO we could use self directly to access fields
+        tmp_tx = Transaction.copy(self)
 
         # acquiring the signature type
         # sign_all = sig_hash & 0x03 == SIGHASH_ALL
@@ -914,8 +939,9 @@ def get_transaction_taproot_digest(
 
         # Data about the transaction
         if not anyone_can_pay:
+            # print('1')
             # the SHA256 of the serialization of all input outpoints
-            for txin in self.inputs:
+            for txin in tmp_tx.inputs:
                 hash_prevouts += h_to_b(txin.txid)[::-1] + struct.pack(
                     "<I",
                     txin.txout_index,
@@ -938,13 +964,14 @@ def get_transaction_taproot_digest(
             tx_for_signing += hash_script_pubkeys
 
             # the SHA256 of the serialization of all input nSequence
-            for txin in self.inputs:
+            for txin in tmp_tx.inputs:
                 hash_sequences += txin.sequence
             hash_sequences = hashlib.sha256(hash_sequences).digest()
             tx_for_signing += hash_sequences
 
         if not (sighash_none or sighash_single):
-            for txout in self.outputs:
+            # print('2')
+            for txout in tmp_tx.outputs:
                 amount_bytes = struct.pack("<Q", txout.amount)
                 script_bytes = txout.script_pubkey.to_bytes()
                 hash_outputs += (
@@ -959,7 +986,8 @@ def get_transaction_taproot_digest(
         tx_for_signing += bytes([spend_type])
 
         if anyone_can_pay:
-            txin = self.inputs[txin_index]
+            # print('3')
+            txin = tmp_tx.inputs[txin_index]
             # convert txid to big-endian first
             tx_for_signing += h_to_b(txin.txid)[::-1] + struct.pack(
                 "<I",
@@ -974,15 +1002,16 @@ def get_transaction_taproot_digest(
 
             tx_for_signing += txin.sequence
         else:
+            # print('4')
             tx_for_signing += txin_index.to_bytes(4, "little")
 
-        if hasattr(self, 'annex') and self.annex is not None:
-            annex_data = self.annex[txin_index] if isinstance(self.annex, list) else self.annex
-            tx_for_signing += prepend_compact_size(h_to_b(annex_data))
+        # TODO if annex is present it should be added here
+        # length of annex should use compact_size
 
         # Data about this output
         if sighash_single:
-            txout = self.outputs[txin_index]
+            # print('5')
+            txout = tmp_tx.outputs[txin_index]
             amount_bytes = struct.pack("<Q", txout.amount)
             script_bytes = txout.script_pubkey.to_bytes()
             hash_output = (