Skip to content
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

feat: smt verification #6115

Merged
merged 2 commits into from
Feb 1, 2024
Merged

feat: smt verification #6115

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
2ae2fa7
SMT verification
hansieodendaal Feb 1, 2024
e044133
fmt
hansieodendaal Feb 1, 2024
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
29 changes: 18 additions & 11 deletions base_layer/core/src/base_node/sync/horizon_state_sync/synchronizer.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -622,7 +622,6 @@ impl<'a, B: BlockchainBackend + 'static> HorizonStateSynchronization<'a, B> {
let mut last_sync_timer = Instant::now();
let mut avg_latency = RollingAverageTime::new(20);

let mut prev_header: Option<BlockHeader> = None;
let mut inputs_to_delete = Vec::new();
while let Some(response) = output_stream.next().await {
let latency = last_sync_timer.elapsed();
Expand All @@ -631,23 +630,13 @@ impl<'a, B: BlockchainBackend + 'static> HorizonStateSynchronization<'a, B> {

let output_header_hash = FixedHash::try_from(res.mined_header)
.map_err(|_| HorizonSyncError::IncorrectResponse("Peer sent no mined header".into()))?;
// We only verify the SMT per header for consecutive syncs
if tip_header.height() > 0 {
if let Some(header) = prev_header.clone() {
if header.hash() != output_header_hash {
// Verify the SMT for the previous header
HorizonStateSynchronization::<B>::check_output_smt_root_hash(&mut output_smt, &header)?;
}
}
}
let current_header = self
.db()
.fetch_header_by_block_hash(output_header_hash)
.await?
.ok_or_else(|| {
HorizonSyncError::IncorrectResponse("Peer sent mined header we do not know of".into())
})?;
prev_header = Some(current_header.clone());

let proto_output = res
.txo
Expand Down Expand Up @@ -728,6 +717,24 @@ impl<'a, B: BlockchainBackend + 'static> HorizonStateSynchronization<'a, B> {
sync_peer.add_sample(last_sync_timer.elapsed());
last_sync_timer = Instant::now();
}
// The SMT can only be verified after all outputs have been downloaded, due to the way we optimize fetching
// outputs from the sync peer. As an example:
// 1. Initial sync:
// - We request outputs from height 0 to 100 (the tranche)
// - The sync peer only returns outputs per block that would still be unspent at height 100 and all inputs
// per block. All outputs that were created and spent within the tranche are never returned.
// - For example, an output is created in block 50 and spent in block 70. It would be included in the SMT for
// headers from height 50 to 69, but due to the optimization, the sync peer would never know about it.
// 2. Consecutive sync:
// - We request outputs from height 101 to 200 (the tranche)
// - The sync peer only returns outputs per block that would still be unspent at height 200, as well as all
// inputs per block, but in this case, only those inputs that are not an output of the current tranche of
// outputs. Similarly, all outputs created and spent within the tranche are never returned.
// - For example, an output is created in block 110 and spent in block 180. It would be included in the SMT
// for headers from height 110 to 179, but due to the optimization, the sync peer would never know about
// it.
// 3. In both cases it would be impossible to verify the SMT per block, as we would not be able to update the
// SMT with the outputs that were created and spent within the tranche.
HorizonStateSynchronization::<B>::check_output_smt_root_hash(&mut output_smt, to_header)?;

// Commit in chunks to avoid locking the database for too long
Expand Down
Loading