4d8d21320e sign: don't assume we are parsing a sane Miniscript (Antoine Poinsot)
Pull request description:
The script provided for signature might be externally provided, for instance by way of 'finalizepsbt'. Therefore the script might be ill-crafted, so don't assume pubkeys are always 32 bytes.
Thanks to Niklas for finding this.
FIxes https://github.com/bitcoin/bitcoin/issues/29851.
ACKs for top commit:
achow101:
ACK 4d8d21320e
furszy:
ACK 4d8d21320e with a small nuance that could be tackled in a follow-up by someone else (or never).
Tree-SHA512: 29b7948b56e6dc05eac1014d684f2129ab1d19cb1e5d304216c826b7057c0e1d84ceb18731b91124b680e17d90e38de9f9a5526e4f6ecc3ea816881a6599bb47