📅 Original date posted:2017-09-12
📝 Original message:On Wed, Sep 13, 2017 at 4:57 AM, Mark Friedenbach via bitcoin-dev
<bitcoin-dev at lists.linuxfoundation.org> wrote:
>> Without the limit I think we would be DoS-ed to dead
>
> 4MB of secp256k1 signatures takes 10s to validate on my 5 year old
> laptop (125,000 signatures, ignoring public keys and other things that
> would consume space). That's much less than bad blocks that can be
> constructed using other vulnerabilities.
Sidenote-ish, but I also believe it would be fairly trivial to keep a
per UTXO tally and demand additional fees when trying to respend a
UTXO which was previously "spent" with an invalid op count. I.e. if
you sign off on an input for a tx that you know is bad, the UTXO in
question will be penalized proportionately to the wasted ops when
included in another transaction later. That would probably kill that
DoS attack as the attacker would effectively lose bitcoin every time,
even if it was postponed until they spent the UTXO. The only thing
clients would need to do is to add a fee rate penalty ivar and a
mapping of outpoint to penalty value, probably stored as a separate
.dat file. I think.
Karl Johan Alm [ARCHIVE] /
npub1e7…fg307
2023-06-07 18:05:36
in reply to nevent1q…m977
Author Public Key
npub1e7vdq905zr4xjr5nxuz58l9jcvffxq728ysl6m2xxgr024mjy5vq4fg307Published at
2023-06-07 18:05:36Event JSON
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"content": "📅 Original date posted:2017-09-12\n📝 Original message:On Wed, Sep 13, 2017 at 4:57 AM, Mark Friedenbach via bitcoin-dev\n\u003cbitcoin-dev at lists.linuxfoundation.org\u003e wrote:\n\u003e\u003e Without the limit I think we would be DoS-ed to dead\n\u003e\n\u003e 4MB of secp256k1 signatures takes 10s to validate on my 5 year old\n\u003e laptop (125,000 signatures, ignoring public keys and other things that\n\u003e would consume space). That's much less than bad blocks that can be\n\u003e constructed using other vulnerabilities.\n\nSidenote-ish, but I also believe it would be fairly trivial to keep a\nper UTXO tally and demand additional fees when trying to respend a\nUTXO which was previously \"spent\" with an invalid op count. I.e. if\nyou sign off on an input for a tx that you know is bad, the UTXO in\nquestion will be penalized proportionately to the wasted ops when\nincluded in another transaction later. That would probably kill that\nDoS attack as the attacker would effectively lose bitcoin every time,\neven if it was postponed until they spent the UTXO. The only thing\nclients would need to do is to add a fee rate penalty ivar and a\nmapping of outpoint to penalty value, probably stored as a separate\n.dat file. I think.",
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