// Copyright 2017-2020 Parity Technologies (UK) Ltd.
// This file is part of Polkadot.
// Polkadot is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Polkadot is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Polkadot. If not, see .
//! Polkadot-specific GRANDPA integration utilities.
use polkadot_primitives::v1::Hash;
use sp_runtime::traits::{Block as BlockT, NumberFor};
/// A custom GRANDPA voting rule that "pauses" voting (i.e. keeps voting for the
/// same last finalized block) after a given block at height `N` has been
/// finalized and for a delay of `M` blocks, i.e. until the best block reaches
/// `N` + `M`, the voter will keep voting for block `N`.
pub(crate) struct PauseAfterBlockFor(pub(crate) N, pub(crate) N);
impl grandpa::VotingRule for PauseAfterBlockFor> where
Block: BlockT,
B: sp_blockchain::HeaderBackend,
{
fn restrict_vote(
&self,
backend: &B,
base: &Block::Header,
best_target: &Block::Header,
current_target: &Block::Header,
) -> Option<(Block::Hash, NumberFor)> {
use sp_runtime::generic::BlockId;
use sp_runtime::traits::Header as _;
// walk backwards until we find the target block
let find_target = |
target_number: NumberFor,
current_header: &Block::Header
| {
let mut target_hash = current_header.hash();
let mut target_header = current_header.clone();
loop {
if *target_header.number() < target_number {
unreachable!(
"we are traversing backwards from a known block; \
blocks are stored contiguously; \
qed"
);
}
if *target_header.number() == target_number {
return Some((target_hash, target_number));
}
target_hash = *target_header.parent_hash();
target_header = backend.header(BlockId::Hash(target_hash)).ok()?
.expect("Header known to exist due to the existence of one of its descendents; qed");
}
};
// only restrict votes targeting a block higher than the block
// we've set for the pause
if *current_target.number() > self.0 {
// if we're past the pause period (i.e. `self.0 + self.1`)
// then we no longer need to restrict any votes
if *best_target.number() > self.0 + self.1 {
return None;
}
// if we've finalized the pause block, just keep returning it
// until best number increases enough to pass the condition above
if *base.number() >= self.0 {
return Some((base.hash(), *base.number()));
}
// otherwise find the target header at the pause block
// to vote on
return find_target(self.0, current_target);
}
None
}
}
/// GRANDPA hard forks due to borked migration of session keys after a runtime
/// upgrade (at #1491596), the signalled authority set changes were invalid
/// (blank keys) and were impossible to finalize. The authorities for these
/// intermediary pending changes are replaced with a static list comprised of
/// w3f validators and randomly selected validators from the latest session (at
/// #1500988).
pub(crate) fn kusama_hard_forks() -> Vec<(
grandpa_primitives::SetId,
(Hash, polkadot_primitives::v1::BlockNumber),
grandpa_primitives::AuthorityList,
)> {
use sp_core::crypto::Ss58Codec;
use std::str::FromStr;
let forks = vec![
(
623,
"01e94e1e7e9cf07b3b0bf4e1717fce7448e5563901c2ef2e3b8e9ecaeba088b1",
1492283,
),
(
624,
"ddc4323c5e8966844dfaa87e0c2f74ef6b43115f17bf8e4ff38845a62d02b9a9",
1492436,
),
(
625,
"38ba115b296663e424e32d7b1655cd795719cef4fd7d579271a6d01086cf1628",
1492586,
),
(
626,
"f3172b6b8497c10fc772f5dada4eeb1f4c4919c97de9de2e1a439444d5a057ff",
1492955,
),
(
627,
"b26526aea299e9d24af29fdacd5cf4751a663d24894e3d0a37833aa14c58424a",
1493338,
),
(
628,
"3980d024327d53b8d01ef0d198a052cd058dd579508d8ed6283fe3614e0a3694",
1493913,
),
(
629,
"31f22997a786c25ee677786373368cae6fd501fd1bc4b212b8e267235c88179d",
1495083,
),
(
630,
"1c65eb250cf54b466c64f1a4003d1415a7ee275e49615450c0e0525179857eef",
1497404,
),
(
631,
"9e44116467cc9d7e224e36487bf2cf571698cae16b25f54a7430f1278331fdd8",
1498598,
),
];
let authorities = vec![
"CwjLJ1zPWK5Ao9WChAFp7rWGEgN3AyXXjTRPrqgm5WwBpoS",
"Dp8FHpZTzvoKXztkfrUAkF6xNf6sjVU5ZLZ29NEGUazouou",
"DtK7YfkhNWU6wEPF1dShsFdhtosVAuJPLkoGhKhG1r5LjKq",
"FLnHYBuoyThzqJ45tdb8P6yMLdocM7ir27Pg1AnpYoygm1K",
"FWEfJ5UMghr52UopgYjawAg6hQg3ztbQek75pfeRtLVi8pB",
"ECoLHAu7HKWGTB9od82HAtequYj6hvNHigkGSB9g3ApxAwB",
"GL1Tg3Uppo8GYL9NjKj4dWKcS6tW98REop9G5hpu7HgFwTa",
"ExnjU5LZMktrgtQBE3An6FsQfvaKG1ukxPqwhJydgdgarmY",
"CagLpgCBu5qJqYF2tpFX6BnU4yHvMGSjc7r3Ed1jY3tMbQt",
"DsrtmMsD4ijh3n4uodxPoiW9NZ7v7no5wVvPVj8fL1dfrWB",
"HQB4EctrVR68ozZDyBiRJzLRAEGh1YKgCkAsFjJcegL9RQA",
"H2YTYbXTFkDY1cGnv164ecnDT3hsD2bQXtyiDbcQuXcQZUV",
"H5WL8jXmbkCoEcLfvqJkbLUeGrDFsJiMXkhhRWn3joct1tE",
"DpB37GDrJDYcmg2df2eqsrPKMay1u8hyZ6sQi2FuUiUeNLu",
"FR8yjKRA9MTjvFGK8kfzrdC23Fr6xd7rfBvZXSjAsmuxURE",
"DxHPty3B9fpj3duu6Gc6gCSCAvsydJHJEY5G3oVYT8S5BYJ",
"DbVKC8ZJjevrhqSnZyJMMvmPL7oPPL4ed1roxawYnHVgyin",
"DVJV81kab2J6oTyRJ9T3NCwW2DSrysbWCssvMcE6cwZHnAd",
"Fg4rDAyzoVzf39Zo8JFPo4W314ntNWNwm3shr4xKe8M1fJg",
"GUaNcnAruMVxHGTs7gGpSUpigRJboQYQBBQyPohkFcP6NMH",
"J4BMGF4W9yWiJz4pkhQW73X6QMGpKUzmPppVnqzBCqw5dQq",
"E1cR61L1tdDEop4WdWVqcq1H1x6VqsDpSHvFyUeC41uruVJ",
"GoWLzBsj1f23YtdDpyntnvN1LwXKhF5TEeZvBeTVxofgWGR",
"CwHwmbogSwtRbrkajVBNubPvWmHBGU4bhMido54M9CjuKZD",
"FLT63y9oVXJnyiWMAL4RvWxsQx21Vymw9961Z7NRFmSG7rw",
"FoQ2y6JuHuHTG4rHFL3f2hCxfJMvtrq8wwPWdv8tsdkcyA8",
"D7QQKqqs8ocGorRA12h4QoBSHDia1DkHeXT4eMfjWQ483QH",
"J6z7FP35F9DiiU985bhkDTS3WxyeTBeoo9MtLdLoD3GiWPj",
"EjapydCK25AagodRbDECavHAy8yQY1tmeRhwUXhVWx4cFPv",
"H8admATcRkGCrF1dTDDBCjQDsYjMkuPaN9YwR2mSCj4DWMQ",
"FtHMRU1fxsoswJjBvyCGvECepC7gP2X77QbNpyikYSqqR6k",
"DzY5gwr45GVRUFzRMmeg8iffpqYF47nm3XbJhmjG97FijaE",
"D3HKWAihSUmg8HrfeFrftSwNK7no261yA9RNr3LUUdsuzuJ",
"D82DwwGJGTcSvtB3SmNrZejnSertbPzpkYvDUp3ibScL3ne",
"FTPxLXLQvMDQYFA6VqNLGwWPKhemMYP791XVj8TmDpFuV3b",
"FzGfKmS7N8Z1tvCBU5JH1eBXZQ9pCtRNoMUnNVv38wZNq72",
"GDfm1MyLAQ7Rh8YPtF6FtMweV4hz91zzeDy2sSABNNqAbmg",
"DiVQbq7sozeKp7PXPM1HLFc2m7ih8oepKLRK99oBY3QZak1",
"HErWh7D2RzrjWWB2fTJfcAejD9MJpadeWWZM2Wnk7LiNWfG",
"Es4DbDauYZYyRJbr6VxrhdcM1iufP9GtdBYf3YtSEvdwNyb",
"EBgXT6FaVo4WsN2LmfnB2jnpDFf4zay3E492RGSn6v1tY99",
"Dr9Zg4fxZurexParztL9SezFeHsPwdP8uGgULeRMbk8DDHJ",
"JEnSTZJpLh91cSryptj57RtFxq9xXqf4U5wBH3qoP91ZZhN",
"DqtRkrmtPANa8wrYR7Ce2LxJxk2iNFtiCxv1cXbx54uqdTN",
"GaxmF53xbuTFKopVEseWiaCTa8fC6f99n4YfW8MGPSPYX3s",
"EiCesgkAaighBKMpwFSAUdvwE4mRjBjNmmd5fP6d4FG8DAx",
"HVbwWGUx7kCgUGap1Mfcs37g6JAZ5qsfsM7TsDRcSqvfxmd",
"G45bc8Ajrd6YSXav77gQwjjGoAsR2qiGd1aLzkMy7o1RLwd",
"Cqix2rD93Mdf7ytg8tBavAig2TvhXPgPZ2mejQvkq7qgRPq",
"GpodE2S5dPeVjzHB4Drm8R9rEwcQPtwAspXqCVz1ooFWf5K",
"CwfmfRmzPKLj3ntSCejuVwYmQ1F9iZWY4meQrAVoJ2G8Kce",
"Fhp5NPvutRCJ4Gx3G8vCYGaveGcU3KgTwfrn5Zr8sLSgwVx",
"GeYRRPkyi23wSF3cJGjq82117fKJZUbWsAGimUnzb5RPbB1",
"DzCJ4y5oT611dfKQwbBDVbtCfENTdMCjb4KGMU3Mq6nyUMu",
];
let authorities = authorities
.into_iter()
.map(|address| {
(
grandpa_primitives::AuthorityId::from_ss58check(address)
.expect("hard fork authority addresses are static and they should be carefully defined; qed."),
1,
)
})
.collect::>();
forks
.into_iter()
.map(|(set_id, hash, number)| {
let hash = Hash::from_str(hash)
.expect("hard fork hashes are static and they should be carefully defined; qed.");
(set_id, (hash, number), authorities.clone())
})
.collect()
}
#[cfg(test)]
mod tests {
use polkadot_test_runtime_client::prelude::*;
use polkadot_test_runtime_client::sp_consensus::BlockOrigin;
use sc_block_builder::BlockBuilderProvider;
use grandpa::VotingRule;
use sp_blockchain::HeaderBackend;
use sp_runtime::generic::BlockId;
use sp_runtime::traits::Header;
use std::sync::Arc;
#[test]
fn grandpa_pause_voting_rule_works() {
let _ = env_logger::try_init();
let client = Arc::new(polkadot_test_runtime_client::new());
let mut push_blocks = {
let mut client = client.clone();
let mut base = 0;
move |n| {
for i in 0..n {
let mut builder = client.new_block(Default::default()).unwrap();
for extrinsic in polkadot_test_runtime_client::needed_extrinsics(vec![], base + i) {
builder.push(extrinsic).unwrap()
}
let block = builder.build().unwrap().block;
client.import(BlockOrigin::Own, block).unwrap();
}
base += n;
}
};
let get_header = {
let client = client.clone();
move |n| client.header(&BlockId::Number(n)).unwrap().unwrap()
};
// the rule should filter all votes after block #20
// is finalized until block #50 is imported.
let voting_rule = super::PauseAfterBlockFor(20, 30);
// add 10 blocks
push_blocks(10);
assert_eq!(
client.info().best_number,
10,
);
// we have not reached the pause block
// therefore nothing should be restricted
assert_eq!(
voting_rule.restrict_vote(
&*client,
&get_header(0),
&get_header(10),
&get_header(10),
),
None,
);
// add 15 more blocks
// best block: #25
push_blocks(15);
// we are targeting the pause block,
// the vote should not be restricted
assert_eq!(
voting_rule.restrict_vote(
&*client,
&get_header(10),
&get_header(20),
&get_header(20),
),
None,
);
// we are past the pause block, votes should
// be limited to the pause block.
let pause_block = get_header(20);
assert_eq!(
voting_rule.restrict_vote(
&*client,
&get_header(10),
&get_header(21),
&get_header(21),
),
Some((pause_block.hash(), *pause_block.number())),
);
// we've finalized the pause block, so we'll keep
// restricting our votes to it.
assert_eq!(
voting_rule.restrict_vote(
&*client,
&pause_block, // #20
&get_header(21),
&get_header(21),
),
Some((pause_block.hash(), *pause_block.number())),
);
// add 30 more blocks
// best block: #55
push_blocks(30);
// we're at the last block of the pause, this block
// should still be considered in the pause period
assert_eq!(
voting_rule.restrict_vote(
&*client,
&pause_block, // #20
&get_header(50),
&get_header(50),
),
Some((pause_block.hash(), *pause_block.number())),
);
// we're past the pause period, no votes should be filtered
assert_eq!(
voting_rule.restrict_vote(
&*client,
&pause_block, // #20
&get_header(51),
&get_header(51),
),
None,
);
}
}