On Tue, Dec 11, 2018 at 05:50:24PM -0500, Russell O'Connor via bitcoin-dev wrote: > On Sun, Dec 9, 2018 at 2:13 PM Johnson Lau <jl2...@xbt.hk> wrote: > The current proposal is that a 64-byte signature will be used for the > default “signing all” sighash, and 65-byte for other sighash types. The > space saved will allow a few more txs in a block, so I think it worths > doing. However, this also makes witness weight estimation more difficult > in > multisig cases.
This seems strange to me -- why wouldn't you just assume every signature is 65 witness bytes, and just be grateful for the prioritisation benefit if someone chooses a shorter signature? Your error margin is just 0.25 vbytes per signature. > I tend to think in opposite terms. Is there a proof that any script can be > transformed into an equivalent one that avoids witness weight malleability? An alternative generalisation: is there a proof that all valid witnesses will have a weight within some small range? > Moreover, even if witness weight malleability is entirely avoidable, it always > seems to come at a cost. Taking as an example libwally's proposed " > csv_2of3_then_2" Script, it begins with "OP_DEPTH OP_1SUB OP_1SUB" (DEPTH 2 NUMNOTEQUAL seems like it would have been more obvious...) Cheers, aj _______________________________________________ bitcoin-dev mailing list bitcoin-dev@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
