Legacy chain check and tests

zebra-chain/src/parameters/network_upgrade.rs

@@ -56,7 +56,8 @@ pub(crate) const MAINNET_ACTIVATION_HEIGHTS: &[(block::Height, NetworkUpgrade)]
     (block::Height(653_600), Blossom),
     (block::Height(903_000), Heartwood),
     (block::Height(1_046_400), Canopy),
-    // TODO: Add Nu5 mainnet activation height
+    // TODO: Add the correct Nu5 mainnet activation height
+    (block::Height(10_000_000), Nu5),
 ];
 
 /// Testnet network upgrade activation heights.
@@ -71,7 +72,8 @@ pub(crate) const TESTNET_ACTIVATION_HEIGHTS: &[(block::Height, NetworkUpgrade)]
     (block::Height(584_000), Blossom),
     (block::Height(903_800), Heartwood),
     (block::Height(1_028_500), Canopy),
-    // TODO: Add Nu5 testnet activation height
+    // TODO: Add the correct Nu5 testnet activation height
+    (block::Height(10_000_000), Nu5),
 ];
 
 /// The Consensus Branch Id, used to bind transactions and blocks to a

zebra-state/src/request.rs

@@ -316,4 +316,7 @@ pub enum Request {
         /// Optionally, the hash of the last header to request.
         stop: Option<block::Hash>,
     },
+
+    /// Returns `Some(database_path)` if Zebra has followed a legacy chain.
+    IsLegacyChain,
 }

zebra-state/src/response.rs

@@ -41,4 +41,7 @@ pub enum Response {
 
     /// The response to a `FindBlockHeaders` request.
     BlockHeaders(Vec<block::CountedHeader>),
+
+    /// The response to a `IsLegacyChain` request.
+    LegacyChain(Option<std::path::PathBuf>),
 }

zebra-state/src/service.rs

@@ -14,8 +14,8 @@ use tower::{util::BoxService, Service};
 use tracing::instrument;
 use zebra_chain::{
     block::{self, Block},
-    parameters::Network,
     parameters::POW_AVERAGING_WINDOW,
+    parameters::{Network, NetworkUpgrade},
     transaction,
     transaction::Transaction,
     transparent,
@@ -664,6 +664,17 @@ impl Service<Request> for StateService {
                     .collect();
                 async move { Ok(Response::BlockHeaders(res)) }.boxed()
             }
+            Request::IsLegacyChain => {
+                let mut response = None;
+                if let Some(tip) = self.best_tip() {
+                    if legacy_chain_check(tip.0, self.any_ancestor_blocks(tip.1), self.network)
+                        .is_err()
+                    {
+                        response = Some(self.disk.path().to_path_buf());
+                    }
+                }
+                async move { Ok(response).map(Response::LegacyChain) }.boxed()
+            }
         }
     }
 }
@@ -679,3 +690,46 @@ impl Service<Request> for StateService {
 pub fn init(config: Config, network: Network) -> BoxService<Request, Response, BoxError> {
     BoxService::new(StateService::new(config, network))
 }
+
+/// Check if zebra is following a legacy chain and return an error if so.
+pub fn legacy_chain_check<I>(
+    tip_height: block::Height,
+    ancestors: I,
+    network: Network,
+) -> Result<(), BoxError>
+where
+    I: Iterator<Item = Arc<Block>>,
+{
+    const MAX_BLOCKS_TO_CHECK: usize = 100;
+
+    // Only do the check if we have an Nu5 activation height.
+    if let Some(nu5_height) = NetworkUpgrade::Nu5.activation_height(network) {
+        // And only do the check if we are above Nu5 activation.
+        if tip_height >= nu5_height {
+            for (count, block) in ancestors.enumerate() {
+                if count >= MAX_BLOCKS_TO_CHECK {
+                    return Err("giving up after checking too many blocks".into());
+                }
+
+                // All transaction `network_upgrade` fields must be consistent with the block height.
+                if block
+                    .check_transaction_network_upgrade_consistency(network)
+                    .is_err()
+                {
+                    return Err("inconsistent network upgrade found in transaction".into());
+                }
+
+                // If we find at least one transaction with a `network_upgrade` field we are ok.
+                let network_upgrades: Vec<NetworkUpgrade> = block
+                    .transactions
+                    .iter()
+                    .filter_map(|trans| trans.network_upgrade())
+                    .collect();
+                if !network_upgrades.is_empty() {
+                    return Ok(());
+                }
+            }
+        }
+    }
+    Ok(())
+}

zebra-state/src/service/tests.rs

@@ -1,10 +1,12 @@
-use std::sync::Arc;
+use std::{env, sync::Arc};
 
 use futures::stream::FuturesUnordered;
 use tower::{util::BoxService, Service, ServiceExt};
 use zebra_chain::{
-    block::Block, parameters::Network, serialization::ZcashDeserializeInto, transaction,
-    transparent,
+    block::{Block, Height},
+    parameters::{Network, NetworkUpgrade},
+    serialization::ZcashDeserializeInto,
+    transaction, transparent,
 };
 use zebra_test::{prelude::*, transcript::Transcript};
 
@@ -97,6 +99,8 @@ async fn test_populated_state_responds_correctly(
             }
         }
 
+        transcript.push((Request::IsLegacyChain, Ok(Response::LegacyChain(None))));
+
         let transcript = Transcript::from(transcript);
         transcript.check(&mut state).await?;
     }
@@ -183,3 +187,87 @@ fn state_behaves_when_blocks_are_committed_out_of_order() -> Result<()> {
 
     Ok(())
 }
+
+#[test]
+fn legacy_chain() -> Result<()> {
+    zebra_test::init();
+
+    legacy_chain_for_network(Network::Mainnet)?;
+    legacy_chain_for_network(Network::Testnet)?;
+
+    Ok(())
+}
+
+/// Test for legacy chain in different scenarios.
+fn legacy_chain_for_network(network: Network) -> Result<()> {
+    zebra_test::init();
+
+    const DEFAULT_PARTIAL_CHAIN_PROPTEST_CASES: u32 = 2;
+    const BLOCKS_AFTER_NU5: u32 = 100;
+
+    if let Some(nu5_height) = NetworkUpgrade::Nu5.activation_height(network) {
+        // Test if we can find at least one transaction with `network_upgrade` field in the chain.
+        let strategy1 = zebra_chain::block::LedgerState::height_strategy(
+            Height(nu5_height.0 + BLOCKS_AFTER_NU5),
+            Some(NetworkUpgrade::Nu5),
+            Some(5),
+            true,
+        )
+        .prop_flat_map(|init| Block::partial_chain_strategy(init, BLOCKS_AFTER_NU5 as usize));
+
+        proptest!(ProptestConfig::with_cases(env::var("PROPTEST_CASES")
+            .ok()
+            .and_then(|v| v.parse().ok())
+            .unwrap_or(DEFAULT_PARTIAL_CHAIN_PROPTEST_CASES)),
+            |(chain in strategy1)| {
+                let response = crate::service::legacy_chain_check(Height(nu5_height.0 + BLOCKS_AFTER_NU5), chain.into_iter(), network);
+                prop_assert_eq!(response.is_err(), false);
+                prop_assert_eq!(response.unwrap(), ());
+            }
+        );
+
+        // Test that we can't find at least one transaction with `network_upgrade` field in the chain.
+        let strategy2 = zebra_chain::block::LedgerState::height_strategy(
+            Height(nu5_height.0 + BLOCKS_AFTER_NU5),
+            Some(NetworkUpgrade::Nu5),
+            Some(4),
+            true,
+        )
+        .prop_flat_map(|init| Block::partial_chain_strategy(init, BLOCKS_AFTER_NU5 as usize + 1));
+
+        proptest!(ProptestConfig::with_cases(env::var("PROPTEST_CASES")
+            .ok()
+            .and_then(|v| v.parse().ok())
+            .unwrap_or(DEFAULT_PARTIAL_CHAIN_PROPTEST_CASES)),
+            |(chain in strategy2)| {
+                let response = crate::service::legacy_chain_check(Height(nu5_height.0 + BLOCKS_AFTER_NU5 + 1), chain.into_iter(), network);
+                prop_assert_eq!(response.is_err(), true);
+                prop_assert_eq!(response.err().unwrap().to_string(), "giving up after checking too many blocks");
+            }
+        );
+
+        // Test that there is at least one transaction in the chain with an inconsistent `network_upgrade` field.
+        let strategy3 = zebra_chain::block::LedgerState::height_strategy(
+            Height(nu5_height.0 + BLOCKS_AFTER_NU5),
+            Some(NetworkUpgrade::Nu5),
+            Some(5),
+            false,
+        )
+        .prop_flat_map(|init| Block::partial_chain_strategy(init, BLOCKS_AFTER_NU5 as usize));
+
+        proptest!(ProptestConfig::with_cases(env::var("PROPTEST_CASES")
+            .ok()
+            .and_then(|v| v.parse().ok())
+            .unwrap_or(DEFAULT_PARTIAL_CHAIN_PROPTEST_CASES)),
+            |(chain in strategy3)| {
+                let response = crate::service::legacy_chain_check(Height(nu5_height.0 + BLOCKS_AFTER_NU5 - 1), chain.into_iter(), network);
+                if response.is_err() {
+                    prop_assert_eq!(response.is_err(), true);
+                    prop_assert_eq!(response.err().unwrap().to_string(), "inconsistent network upgrade found in transaction");
+                }
+            }
+        );
+    }
+
+    Ok(())
+}

zebrad/src/commands/start.rs

@@ -26,7 +26,7 @@
 use abscissa_core::{config, Command, FrameworkError, Options, Runnable};
 use color_eyre::eyre::{eyre, Report};
 use tokio::sync::oneshot;
-use tower::builder::ServiceBuilder;
+use tower::{builder::ServiceBuilder, ServiceExt};
 
 use crate::components::{tokio::RuntimeRun, Inbound};
 use crate::config::ZebradConfig;
@@ -54,6 +54,27 @@ impl StartCmd {
             config.network.network,
         ));
 
+        info!("starting legacy chain check");
+        match state
+            .clone()
+            .oneshot(zebra_state::Request::IsLegacyChain)
+            .await
+        {
+            Ok(zebra_state::Response::LegacyChain(response)) => {
+                if response.is_some() {
+                    // we found a legacy chain
+                    panic!(
+                        "Legacy chain found, database can be corrupted.
+                        Delete your database and retry a full sync.
+                        Database path: {:?}",
+                        response.expect("the corrupted database path")
+                    );
+                }
+            }
+            _ => unreachable!("the legacy chain call should always respond"),
+        };
+        info!("no legacy chain found");
+
         info!("initializing verifiers");
         let verifier = zebra_consensus::chain::init(
             config.consensus.clone(),

zebrad/tests/acceptance.rs

@@ -1327,3 +1327,28 @@ where
 
     Ok(())
 }
+
+#[test]
+fn legacy_chain() -> Result<()> {
+    zebra_test::init();
+
+    // start caches state, so run one of the start tests with persistent state
+    let testdir = testdir()?.with_config(&mut persistent_test_config()?)?;
+
+    let mut child = testdir.spawn_child(&["-v", "start"])?;
+
+    // Run the program and kill it after a few seconds
+    std::thread::sleep(LAUNCH_DELAY);
+    child.kill()?;
+
+    let output = child.wait_with_output()?;
+    let output = output.assert_failure()?;
+
+    output.stdout_line_contains("starting legacy chain check")?;
+    output.stdout_line_contains("no legacy chain found")?;
+
+    // Make sure the command was killed
+    output.assert_was_killed()?;
+
+    Ok(())
+}