[bitcoin-dev] Fwd: Simple change to the "merkleblock" command to protect from SPV proof extension attacks

2018-08-15 Thread Sergio Demian Lerner via bitcoin-dev
Hi, While fixing RSK's SPV bridge I came up with an idea to fix the MERKLEBLOCK command to prevent rogue peers from attacking SPV peers using Bitcoin's Merkle tree structure flaws. The most annoying attack is the one that tries to confuse a victim peer into thinking a transaction is an inner node,

Re: [bitcoin-dev] Claiming an OP_RETURN Prefix

2018-08-15 Thread Christopher Allen via bitcoin-dev
On August 5, 2018 9:11:26 PM UTC, Lautaro Dragan via bitcoin-dev wrote: >Should we actually be using the BIP process to claim a prefix? I recommend against using an op_return prefix, as they allow for transaction censorship. In fact, in our case, where we use an IPFS hash in an op_return, we rem

Re: [bitcoin-dev] Claiming an OP_RETURN Prefix

2018-08-15 Thread Jorge Timón via bitcoin-dev
op_return outputs can be pruned because they are not spendable. putting a hash on in the witness script data won't make things better (it would actually make them worse) and it definitely doesn't help "block size bloat". I think I'm missing some context, but if you're using op_return purely for tim

Re: [bitcoin-dev] Claiming an OP_RETURN Prefix

2018-08-15 Thread Jude Nelson via bitcoin-dev
> I recommend against using an op_return prefix, > as they allow for transaction censorship. > In fact, in our case, where we use an IPFS hash in > an op_return, we remove the IPFS multihash prefix > information to post a “bare” SHA256 hash to look like > many other hashes being posted in op_retur

Re: [bitcoin-dev] Claiming an OP_RETURN Prefix

2018-08-15 Thread Peter Todd via bitcoin-dev
On August 15, 2018 8:33:43 PM UTC, "Jorge Timón via bitcoin-dev" wrote: >op_return outputs can be pruned because they are not spendable. >putting a hash on in the witness script data won't make things better >(it would actually make them worse) and it definitely doesn't help >"block size bloat"

Re: [bitcoin-dev] Claiming an OP_RETURN Prefix

2018-08-15 Thread Christopher Allen via bitcoin-dev
On Wed, Aug 15, 2018 at 2:24 PM Jude Nelson via bitcoin-dev < bitcoin-dev@lists.linuxfoundation.org> wrote: > Can a miner identify which transactions came from your software simply by > running a copy themselves? If so, then they can censor your transactions > no matter how you encode them. > Po

Re: [bitcoin-dev] Claiming an OP_RETURN Prefix

2018-08-15 Thread Luke Dashjr via bitcoin-dev
On Wednesday 15 August 2018 21:54:50 Christopher Allen via bitcoin-dev wrote: > On Wed, Aug 15, 2018 at 2:24 PM Jude Nelson via bitcoin-dev < > bitcoin-dev@lists.linuxfoundation.org> wrote: > > Can a miner identify which transactions came from your software simply by > > running a copy themselves?

Re: [bitcoin-dev] Claiming an OP_RETURN Prefix

2018-08-15 Thread Luke Dashjr via bitcoin-dev
On Thursday 16 August 2018 02:22:21 Lautaro Dragan wrote: > > Choosing not to mine transactions is not censorship. > > Is it not, if for political rather than economical reasons? These > transactions pay fees like any other. Miners have always chosen transaction on "political" basises, and doing s