1
0
SomberNight 0508625afc transaction: add method verify_sig_for_txin
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).
2025-05-18 15:20:19 +00:00
2021-09-13 16:20:54 +00:00
2022-08-10 17:32:23 +02:00
2023-09-05 12:32:38 +00:00
2024-09-18 15:48:38 +00:00
2024-02-21 16:12:22 +00:00
2023-11-13 15:45:05 +00:00
2024-02-16 15:40:45 +01:00

Electrum - Lightweight Bitcoin client

Licence: MIT Licence
Author: Thomas Voegtlin
Language: Python (>= 3.10)
Homepage: https://electrum.org/

Build Status Test coverage statistics Help translate Electrum online

Getting started

(If you've come here looking to simply run Electrum, you may download it here.)

Electrum itself is pure Python, and so are most of the required dependencies, but not everything. The following sections describe how to run from source, but here is a TL;DR:

$ sudo apt-get install libsecp256k1-dev
$ ELECTRUM_ECC_DONT_COMPILE=1 python3 -m pip install --user ".[gui,crypto]"

Not pure-python dependencies

Qt GUI

If you want to use the Qt interface, install the Qt dependencies:

$ sudo apt-get install python3-pyqt6

libsecp256k1

For elliptic curve operations, libsecp256k1 is a required dependency.

If you "pip install" Electrum, by default libsecp will get compiled locally, as part of the electrum-ecc dependency. This can be opted-out of, by setting the ELECTRUM_ECC_DONT_COMPILE=1 environment variable. For the compilation to work, besides a C compiler, you need at least:

$ sudo apt-get install automake libtool

If you opt out of the compilation, you need to provide libsecp in another way, e.g.:

$ sudo apt-get install libsecp256k1-dev

cryptography

Due to the need for fast symmetric ciphers, cryptography is required. Install from your package manager (or from pip):

$ sudo apt-get install python3-cryptography

hardware-wallet support

If you would like hardware wallet support, see this.

Running from tar.gz

If you downloaded the official package (tar.gz), you can run Electrum from its root directory without installing it on your system; all the pure python dependencies are included in the 'packages' directory. To run Electrum from its root directory, just do:

$ ./run_electrum

You can also install Electrum on your system, by running this command:

$ sudo apt-get install python3-setuptools python3-pip
$ python3 -m pip install --user .

This will download and install the Python dependencies used by Electrum instead of using the 'packages' directory. It will also place an executable named electrum in ~/.local/bin, so make sure that is on your PATH variable.

Development version (git clone)

(For OS-specific instructions, see here for Windows, and for macOS)

Check out the code from GitHub:

$ git clone https://github.com/spesmilo/electrum.git
$ cd electrum
$ git submodule update --init

Run install (this should install dependencies):

$ python3 -m pip install --user -e .

Create translations (optional):

$ sudo apt-get install gettext
$ ./contrib/locale/build_locale.sh electrum/locale/locale electrum/locale/locale

Finally, to start Electrum:

$ ./run_electrum

Run tests

Run unit tests with pytest:

$ pytest tests -v

To run a single file, specify it directly like this:

$ pytest tests/test_bitcoin.py -v

Creating Binaries

Contributing

Any help testing the software, reporting or fixing bugs, reviewing pull requests and recent changes, writing tests, or helping with outstanding issues is very welcome. Implementing new features, or improving/refactoring the codebase, is of course also welcome, but to avoid wasted effort, especially for larger changes, we encourage discussing these on the issue tracker or IRC first.

Besides GitHub, most communication about Electrum development happens on IRC, in the #electrum channel on Libera Chat. The easiest way to participate on IRC is with the web client, web.libera.chat.

Languages
Python 89.1%
QML 8.4%
Shell 2%
Dockerfile 0.2%
Java 0.2%
Other 0.1%