Re: [Bitcoin-development] Newly introduced DoS

[Gavin Andresen <gavinandresen@gmail.com>]

On Mon, Sep 26, 2011 at 3:17 PM, Luke-Jr <luke@dashjr.org> wrote:
> +        return DoS(10, error("AcceptToMemoryPool() : transaction with out-of-
> bounds SigOpCount"));
> +                        return DoS(10, error("ConnectInputs() : tried to
> spend coinbase at depth %d", pindexBlock->nHeight - pindex->nHeight));
> These shouldn't be "DoS"'d, or else you open a new DoS when nodes legitimately
> relay such transactions/blocks.

Huh?

So in the future lets suppose we schedule a change to the acceptable
block rules that allows more SigOps in a block, or allows generation
transaction to be spent before 100 confirmations. At that same time,
the DoS rules will be changed.

You cannot "legitimately" relay those blocks without a scheduled
block-chain-split.  If a block-chain-split IS scheduled and the rules
change, then denying service to nodes running old, obsolete versions
of bitcoin is the right thing to do-- it is better to "fail hard" and
find it difficult or impossible to connect to the network rather than
continue with an obsolete client and a non-majority block chain.

(and the third DoS in AcceptBlock(): prev block not found  is a
"should be impossible" case, because AcceptBlock is only called when
extending the best-block chain).

-- 
--
Gavin Andresen