Skip to content

Update BIP91 confirmation window and enforcement. #547

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
luke-jr merged 1 commit into from
Jun 15, 2017
Merged

Update BIP91 confirmation window and enforcement. #547

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
42 changes: 39 additions & 3 deletions bip-0091.mediawiki
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -28,17 +28,52 @@ This BIP provides a way for a simple majority of miners to coordinate activation

==Specification==

While this BIP is active, all blocks must set the nVersion header top 3 bits to 001 together with bit field (1<<1) (according to the existing segwit deployment). Blocks that do not signal as required will be rejected.
While this BIP is active or locked in, all blocks must set the nVersion header top 3 bits to 001 together with bit field (1<<1) (according to the existing segwit deployment). Blocks that do not signal as required will be rejected.

==Deployment==

This BIP will be deployed by a "version bits" with an 80%(this can be adjusted if desired) activation threshold BIP9 with the name "segsignal" and using bit 4.
This BIP will be deployed by a "version bits" with an 80%(this can be adjusted if desired) 538 block activation threshold and 672 block confirmation window BIP9 with the name "segsignal" and using bit 4.

This BIP will have a start time of midnight June 1st, 2017 (epoch time 1496275200) and timeout on midnight November 15th 2017 (epoch time 1510704000). This BIP will cease to be active when segwit is locked-in.

=== Reference implementation ===

<pre>
// Deployment of SEGSIGNAL
consensus.vDeployments[Consensus::DEPLOYMENT_SEGSIGNAL].bit = 4;
consensus.vDeployments[Consensus::DEPLOYMENT_SEGSIGNAL].nStartTime = 1496275200; // June 1st, 2017.
consensus.vDeployments[Consensus::DEPLOYMENT_SEGSIGNAL].nTimeout = 1510704000; // November 15th, 2017.
consensus.vDeployments[Consensus::DEPLOYMENT_SEGSIGNAL].nOverrideMinerConfirmationWindow = 672; // ~4.67 days
Copy link
Copy Markdown
Contributor

@Christewart Christewart Jun 15, 2017

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Your comment says 'immediate enforcement', is that right? Doesn't this indicate there is a 4.67 wait between LOCKED_IN and ACTIVE? (Looking at this graphic https://github.com/bitcoin/bips/blob/master/bip-0009.mediawiki#state-transitions)

Copy link
Copy Markdown
Contributor Author

@jameshilliard jameshilliard Jun 15, 2017

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

It enforces on lock in here.

consensus.vDeployments[Consensus::DEPLOYMENT_SEGSIGNAL].nOverrideRuleChangeActivationThreshold = 538; // 80%

class VersionBitsConditionChecker : public AbstractThresholdConditionChecker {
private:
const Consensus::DeploymentPos id;

protected:
int64_t BeginTime(const Consensus::Params& params) const { return params.vDeployments[id].nStartTime; }
int64_t EndTime(const Consensus::Params& params) const { return params.vDeployments[id].nTimeout; }
int Period(const Consensus::Params& params) const {
if (params.vDeployments[id].nOverrideMinerConfirmationWindow > 0)
return params.vDeployments[id].nOverrideMinerConfirmationWindow;
return params.nMinerConfirmationWindow;
}
int Threshold(const Consensus::Params& params) const {
if (params.vDeployments[id].nOverrideRuleChangeActivationThreshold > 0)
return params.vDeployments[id].nOverrideRuleChangeActivationThreshold;
return params.nRuleChangeActivationThreshold;
}

bool Condition(const CBlockIndex* pindex, const Consensus::Params& params) const
{
return (((pindex->nVersion & VERSIONBITS_TOP_MASK) == VERSIONBITS_TOP_BITS) && (pindex->nVersion & Mask(params)) != 0);
}

public:
VersionBitsConditionChecker(Consensus::DeploymentPos id_) : id(id_) {}
uint32_t Mask(const Consensus::Params& params) const { return ((uint32_t)1) << params.vDeployments[id].bit; }
};

// Check if Segregated Witness is Locked In
bool IsWitnessLockedIn(const CBlockIndex* pindexPrev, const Consensus::Params& params)
{
Expand All @@ -47,7 +82,8 @@ bool IsWitnessLockedIn(const CBlockIndex* pindexPrev, const Consensus::Params& p
}

// SEGSIGNAL mandatory segwit signalling.
if ( VersionBitsState(pindex->pprev, chainparams.GetConsensus(), Consensus::DEPLOYMENT_SEGSIGNAL, versionbitscache) == THRESHOLD_ACTIVE &&
if ((VersionBitsState(pindex->pprev, chainparams.GetConsensus(), Consensus::DEPLOYMENT_SEGSIGNAL, versionbitscache) == THRESHOLD_ACTIVE ||
VersionBitsState(pindex->pprev, chainparams.GetConsensus(), Consensus::DEPLOYMENT_SEGSIGNAL, versionbitscache) == THRESHOLD_LOCKED_IN) &&
!IsWitnessLockedIn(pindex->pprev, chainparams.GetConsensus()) && // Segwit is not locked in
!IsWitnessEnabled(pindex->pprev, chainparams.GetConsensus()) ) // and is not active.
{
Expand Down