(
client: &C,
slot_now: Slot,
mut header: B::Header,
hash: B::Hash,
authorities: &[AuthorityId],
check_for_equivocation: CheckForEquivocation,
) -> Result)>, Error>
where
DigestItemFor: CompatibleDigestItem,
P::Signature: Codec,
C: sc_client_api::backend::AuxStore,
P::Public: Encode + Decode + PartialEq + Clone,
{
let seal = header.digest_mut().pop().ok_or_else(|| Error::HeaderUnsealed(hash))?;
let sig = seal.as_aura_seal().ok_or_else(|| aura_err(Error::HeaderBadSeal(hash)))?;
let slot = find_pre_digest::(&header)?;
if slot > slot_now {
header.digest_mut().push(seal);
Ok(CheckedHeader::Deferred(header, slot))
} else {
// check the signature is valid under the expected authority and
// chain state.
let expected_author =
slot_author::(slot, &authorities).ok_or_else(|| Error::SlotAuthorNotFound)?;
let pre_hash = header.hash();
if P::verify(&sig, pre_hash.as_ref(), expected_author) {
if check_for_equivocation.check_for_equivocation() {
if let Some(equivocation_proof) =
check_equivocation(client, slot_now, slot, &header, expected_author)
.map_err(Error::Client)?
{
info!(
target: "aura",
"Slot author is equivocating at slot {} with headers {:?} and {:?}",
slot,
equivocation_proof.first_header.hash(),
equivocation_proof.second_header.hash(),
);
}
}
Ok(CheckedHeader::Checked(header, (slot, seal)))
} else {
Err(Error::BadSignature(hash))
}
}
}
/// A verifier for Aura blocks.
pub struct AuraVerifier {
client: Arc,
phantom: PhantomData,
create_inherent_data_providers: CIDP,
can_author_with: CAW,
check_for_equivocation: CheckForEquivocation,
telemetry: Option,
}
impl AuraVerifier {
pub(crate) fn new(
client: Arc,
create_inherent_data_providers: CIDP,
can_author_with: CAW,
check_for_equivocation: CheckForEquivocation,
telemetry: Option,
) -> Self {
Self {
client,
create_inherent_data_providers,
can_author_with,
check_for_equivocation,
telemetry,
phantom: PhantomData,
}
}
}
impl AuraVerifier
where
P: Send + Sync + 'static,
CAW: Send + Sync + 'static,
CIDP: Send,
{
async fn check_inherents(
&self,
block: B,
block_id: BlockId,
inherent_data: sp_inherents::InherentData,
create_inherent_data_providers: CIDP::InherentDataProviders,
execution_context: ExecutionContext,
) -> Result<(), Error>
where
C: ProvideRuntimeApi,
C::Api: BlockBuilderApi,
CAW: CanAuthorWith,
CIDP: CreateInherentDataProviders,
{
if let Err(e) = self.can_author_with.can_author_with(&block_id) {
debug!(
target: "aura",
"Skipping `check_inherents` as authoring version is not compatible: {}",
e,
);
return Ok(())
}
let inherent_res = self
.client
.runtime_api()
.check_inherents_with_context(&block_id, execution_context, block, inherent_data)
.map_err(|e| Error::Client(e.into()))?;
if !inherent_res.ok() {
for (i, e) in inherent_res.into_errors() {
match create_inherent_data_providers.try_handle_error(&i, &e).await {
Some(res) => res.map_err(Error::Inherent)?,
None => return Err(Error::UnknownInherentError(i)),
}
}
}
Ok(())
}
}
#[async_trait::async_trait]
impl Verifier for AuraVerifier
where
C: ProvideRuntimeApi
+ Send
+ Sync
+ sc_client_api::backend::AuxStore
+ ProvideCache
+ BlockOf,
C::Api: BlockBuilderApi + AuraApi> + ApiExt,
DigestItemFor: CompatibleDigestItem,
P: Pair + Send + Sync + 'static,
P::Public: Send + Sync + Hash + Eq + Clone + Decode + Encode + Debug + 'static,
P::Signature: Encode + Decode,
CAW: CanAuthorWith + Send + Sync + 'static,
CIDP: CreateInherentDataProviders + Send + Sync,
CIDP::InherentDataProviders: InherentDataProviderExt + Send + Sync,
{
async fn verify(
&mut self,
mut block: BlockImportParams,
) -> Result<(BlockImportParams, Option)>>), String> {
let hash = block.header.hash();
let parent_hash = *block.header.parent_hash();
let authorities = authorities(self.client.as_ref(), &BlockId::Hash(parent_hash))
.map_err(|e| format!("Could not fetch authorities at {:?}: {:?}", parent_hash, e))?;
let create_inherent_data_providers = self
.create_inherent_data_providers
.create_inherent_data_providers(parent_hash, ())
.await
.map_err(|e| Error::::Client(sp_blockchain::Error::Application(e)))?;
let mut inherent_data = create_inherent_data_providers
.create_inherent_data()
.map_err(Error::::Inherent)?;
let slot_now = create_inherent_data_providers.slot();
// we add one to allow for some small drift.
// FIXME #1019 in the future, alter this queue to allow deferring of
// headers
let checked_header = check_header::(
&self.client,
slot_now + 1,
block.header,
hash,
&authorities[..],
self.check_for_equivocation,
)
.map_err(|e| e.to_string())?;
match checked_header {
CheckedHeader::Checked(pre_header, (slot, seal)) => {
// if the body is passed through, we need to use the runtime
// to check that the internally-set timestamp in the inherents
// actually matches the slot set in the seal.
if let Some(inner_body) = block.body.take() {
let new_block = B::new(pre_header.clone(), inner_body);
inherent_data.aura_replace_inherent_data(slot);
// skip the inherents verification if the runtime API is old.
if self
.client
.runtime_api()
.has_api_with::, _>(
&BlockId::Hash(parent_hash),
|v| v >= 2,
)
.map_err(|e| format!("{:?}", e))?
{
self.check_inherents(
new_block.clone(),
BlockId::Hash(parent_hash),
inherent_data,
create_inherent_data_providers,
block.origin.into(),
)
.await
.map_err(|e| e.to_string())?;
}
let (_, inner_body) = new_block.deconstruct();
block.body = Some(inner_body);
}
trace!(target: "aura", "Checked {:?}; importing.", pre_header);
telemetry!(
self.telemetry;
CONSENSUS_TRACE;
"aura.checked_and_importing";
"pre_header" => ?pre_header,
);
// Look for an authorities-change log.
let maybe_keys = pre_header
.digest()
.logs()
.iter()
.filter_map(|l| {
l.try_to::>>(OpaqueDigestItemId::Consensus(
&AURA_ENGINE_ID,
))
})
.find_map(|l| match l {
ConsensusLog::AuthoritiesChange(a) =>
Some(vec![(well_known_cache_keys::AUTHORITIES, a.encode())]),
_ => None,
});
block.header = pre_header;
block.post_digests.push(seal);
block.fork_choice = Some(ForkChoiceStrategy::LongestChain);
block.post_hash = Some(hash);
Ok((block, maybe_keys))
},
CheckedHeader::Deferred(a, b) => {
debug!(target: "aura", "Checking {:?} failed; {:?}, {:?}.", hash, a, b);
telemetry!(
self.telemetry;
CONSENSUS_DEBUG;
"aura.header_too_far_in_future";
"hash" => ?hash,
"a" => ?a,
"b" => ?b,
);
Err(format!("Header {:?} rejected: too far in the future", hash))
},
}
}
}
/// Should we check for equivocation of a block author?
#[derive(Debug, Clone, Copy)]
pub enum CheckForEquivocation {
/// Yes, check for equivocation.
///
/// This is the default setting for this.
Yes,
/// No, don't check for equivocation.
No,
}
impl CheckForEquivocation {
/// Should we check for equivocation?
fn check_for_equivocation(self) -> bool {
matches!(self, Self::Yes)
}
}
impl Default for CheckForEquivocation {
fn default() -> Self {
Self::Yes
}
}
/// Parameters of [`import_queue`].
pub struct ImportQueueParams<'a, Block, I, C, S, CAW, CIDP> {
/// The block import to use.
pub block_import: I,
/// The justification import.
pub justification_import: Option>,
/// The client to interact with the chain.
pub client: Arc,
/// Something that can create the inherent data providers.
pub create_inherent_data_providers: CIDP,
/// The spawner to spawn background tasks.
pub spawner: &'a S,
/// The prometheus registry.
pub registry: Option<&'a Registry>,
/// Can we author with the current node?
pub can_author_with: CAW,
/// Should we check for equivocation?
pub check_for_equivocation: CheckForEquivocation,
/// Telemetry instance used to report telemetry metrics.
pub telemetry: Option,
}
/// Start an import queue for the Aura consensus algorithm.
pub fn import_queue<'a, P, Block, I, C, S, CAW, CIDP>(
ImportQueueParams {
block_import,
justification_import,
client,
create_inherent_data_providers,
spawner,
registry,
can_author_with,
check_for_equivocation,
telemetry,
}: ImportQueueParams<'a, Block, I, C, S, CAW, CIDP>,
) -> Result, sp_consensus::Error>
where
Block: BlockT,
C::Api: BlockBuilderApi + AuraApi> + ApiExt,
C: 'static
+ ProvideRuntimeApi
+ BlockOf
+ ProvideCache
+ Send
+ Sync
+ AuxStore
+ UsageProvider
+ HeaderBackend,
I: BlockImport>
+ Send
+ Sync
+ 'static,
DigestItemFor: CompatibleDigestItem,
P: Pair + Send + Sync + 'static,
P::Public: Clone + Eq + Send + Sync + Hash + Debug + Encode + Decode,
P::Signature: Encode + Decode,
S: sp_core::traits::SpawnEssentialNamed,
CAW: CanAuthorWith + Send + Sync + 'static,
CIDP: CreateInherentDataProviders + Sync + Send + 'static,
CIDP::InherentDataProviders: InherentDataProviderExt + Send + Sync,
{
let verifier = build_verifier::(BuildVerifierParams {
client,
create_inherent_data_providers,
can_author_with,
check_for_equivocation,
telemetry,
});
Ok(BasicQueue::new(verifier, Box::new(block_import), justification_import, spawner, registry))
}
/// Parameters of [`build_verifier`].
pub struct BuildVerifierParams {
/// The client to interact with the chain.
pub client: Arc,
/// Something that can create the inherent data providers.
pub create_inherent_data_providers: CIDP,
/// Can we author with the current node?
pub can_author_with: CAW,
/// Should we check for equivocation?
pub check_for_equivocation: CheckForEquivocation,
/// Telemetry instance used to report telemetry metrics.
pub telemetry: Option,
}
/// Build the [`AuraVerifier`]
pub fn build_verifier(
BuildVerifierParams {
client,
create_inherent_data_providers,
can_author_with,
check_for_equivocation,
telemetry,
}: BuildVerifierParams,
) -> AuraVerifier {
AuraVerifier::<_, P, _, _>::new(
client,
create_inherent_data_providers,
can_author_with,
check_for_equivocation,
telemetry,
)
}