bb530efa18 Disallow extended encoding for non-witness transactions (Pieter Wuille)
Pull request description:
BIP144 specifies that transactions without witness should use the legacy encoding, which is currently not enforced.
This rule was present in the original SegWit implementation (https://github.com/bitcoin/bitcoin/pull/8149), but was subsequently dropped (https://github.com/bitcoin/bitcoin/pull/8589).
As all hashes, txids, and weights are always computed over a reserialized version of a transaction, it is mostly harmless to permit extended encoding for non-segwit transactions, but I'd rather strictly follow the BIP.
ACKs for commit bb530e:
instagibbs:
utACK bb530efa18
stevenroose:
utACK bb530efa18
Tree-SHA512: 1aeccd6a555f43784fefb076ce2e8ad2f5ba7be49840544a50050d0390f82373f87201bf56cf8bb30841b4f9cd893b382261a080da875d4e11ab7051f8640dbe
c65c77c721