- whitespaces are safe to remove from strings, and is convenient if we do this for users
- bytes-like inputs should be left alone: individual bytes that look like whitespaces can appear in them anywhere
- even stripping the leading/trailing whitespaces is not safe to do: the first byte of the nVersion or the last byte of the nLocktime might look like whitespace too!
- instead, leading/trailing whitespaces can be stripped closer to where they are input, e.g. in the GUI
- e.g. ".txn" files that we ourselves create contain a complete tx as a hex string, with a trailing final newline in the file
- instead of reading that as bytes, we can read it as text
- ".psbt" files OTOH are binary
Removes all whitespace characters from a raw transaction string.
This is useful for example when loading raw transactions from text input
as it happens that there are some newline characters in the text.
I noticed this when copying-pasting from a timelock recovery pdf.
This new `Transaction.verify_sig_for_txin` function is an instance method of `Transaction` instead of `PartialTransaction`.
It takes a complete txin, a pubkey and a signature, and verifies the signature.
- `get_preimage_script` is renamed to `get_scriptcode_for_sighash` and now effectively has two implementations:
- the old impl became `PartialTxInput.get_scriptcode_for_sighash`
- this assumes we are the ones constructing a spending txin and can have knowledge beyond what will be revealed onchain
- the new impl is in the base class, `TxInput.get_scriptcode_for_sighash`
- this assumes the txin is already "complete", and mimics a consensus-verifier by extracting the required fields
from the already complete witness/scriptSig and the scriptpubkey of the funding utxo
- `serialize_preimage` now does not require a PartialTransaction, it also works on the base class Transaction
-----
I intend to use this for debugging only atm: I noticed TxBatcher sometimes creates invalid signatures by seeing
that bitcoind rejects txs with `mandatory-script-verify-flag-failed (Signature must be zero for failed CHECK(MULTI)SIG operation)`.
However the txs in question have multiple txins, with some txins containing multiple signatures, and bitcoind does not tell us
which txin/signature is invalid. Knowing which signature is invalid would be a start, but I can now add some temp debug logging
to `serialize_preimage` to compare the message being signed with the message being verified.
As can be seen from the tests, the signature and the pubkey needs to be manually extracted from the txin to be verified:
we still don't have a script interpreter so we don't have logic to "verify a txin". However this new code adds logic
to verify a signature for a txin/pubkey combo (which is a small part of an interpreter/verifier).
Add support for key-path-spending taproot utxos into transaction.py.
- no wallet support yet
- add some psbt, and minimal descriptor support
- preliminary work towards script-path spends
Instead of some functions operating with hex strings,
and others using bytes, this consolidates most things to use bytes.
This mainly focuses on bitcoin.py and transaction.py,
and then adapts the API usages in other files.
Notably,
- scripts,
- pubkeys,
- signatures
should be bytes in almost all places now.
