feat: check chain metadata (#6146)

Description
---
Checks chain metadata for correctness

Motivation and Context
---
The base node makes certain logic desisions based on what the chain meta
data is, but no where do we make checks to ensure that the data is valid
inside of this.

How Has This Been Tested?
---
unit tests

base_layer/common_types/src/chain_metadata.rs

@@ -47,6 +47,13 @@ pub struct ChainMetadata {
     /// Timestamp of the tip block in the longest valid chain
     timestamp: u64,
 }
+#[derive(Debug, thiserror::Error)]
+pub enum ChainMetaDataError {
+    #[error("Pruning Height is higher than the Best Block height")]
+    PruningHeightAboveBestBlock,
+    #[error("The total accumulated difficulty is zero")]
+    AccumulatedDifficultyZero,
+}
 
 impl ChainMetadata {
     pub fn new(
@@ -56,15 +63,22 @@ impl ChainMetadata {
         pruned_height: u64,
         accumulated_difficulty: U256,
         timestamp: u64,
-    ) -> ChainMetadata {
-        ChainMetadata {
+    ) -> Result<ChainMetadata, ChainMetaDataError> {
+        let chain_meta_data = ChainMetadata {
             best_block_height,
             best_block_hash,
             pruning_horizon,
             pruned_height,
             accumulated_difficulty,
             timestamp,
-        }
+        };
+        if chain_meta_data.accumulated_difficulty == 0.into() {
+            return Err(ChainMetaDataError::AccumulatedDifficultyZero);
+        };
+        if chain_meta_data.pruned_height > chain_meta_data.best_block_height {
+            return Err(ChainMetaDataError::PruningHeightAboveBestBlock);
+        };
+        Ok(chain_meta_data)
     }
 
     /// The block height at the pruning horizon, given the chain height of the network. Typically database backends

base_layer/core/src/base_node/proto/chain_metadata.rs

@@ -56,14 +56,15 @@ impl TryFrom<proto::ChainMetadata> for ChainMetadata {
             .best_block_hash
             .try_into()
             .map_err(|e| format!("Malformed best block: {}", e))?;
-        Ok(ChainMetadata::new(
+        ChainMetadata::new(
             best_block_height,
             hash,
             pruning_horizon,
             metadata.pruned_height,
             accumulated_difficulty,
             metadata.timestamp,
-        ))
+        )
+        .map_err(|e| e.to_string())
     }
 }
 

base_layer/core/src/base_node/state_machine_service/states/listening.rs

@@ -456,7 +456,7 @@ mod test {
 
         let archival_node = PeerChainMetadata::new(
             random_node_id(),
-            ChainMetadata::new(NETWORK_TIP_HEIGHT, block_hash, 0, 0, accumulated_difficulty, 0),
+            ChainMetadata::new(NETWORK_TIP_HEIGHT, block_hash, 0, 0, accumulated_difficulty, 0).unwrap(),
             None,
         );
 
@@ -469,7 +469,8 @@ mod test {
                 0,
                 accumulated_difficulty - U256::from(1000),
                 0,
-            ),
+            )
+            .unwrap(),
             None,
         );
 

base_layer/core/src/base_node/sync/sync_peer.rs

@@ -135,7 +135,6 @@ mod test {
     use super::*;
 
     mod sort_by_latency {
-        use primitive_types::U256;
         use tari_common_types::types::FixedHash;
         use tari_comms::types::{CommsPublicKey, CommsSecretKey};
         use tari_crypto::keys::{PublicKey, SecretKey};
@@ -151,7 +150,7 @@ mod test {
             let latency_option = latency.map(|latency| Duration::from_millis(latency as u64));
             PeerChainMetadata::new(
                 node_id,
-                ChainMetadata::new(0, FixedHash::zero(), 0, 0, U256::zero(), 0),
+                ChainMetadata::new(0, FixedHash::zero(), 0, 0, 1.into(), 0).unwrap(),
                 latency_option,
             )
             .into()

base_layer/core/src/chain_storage/error.rs

@@ -21,7 +21,7 @@
 // USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 use lmdb_zero::error;
-use tari_common_types::types::FixedHashSizeError;
+use tari_common_types::{chain_metadata::ChainMetaDataError, types::FixedHashSizeError};
 use tari_mmr::{error::MerkleMountainRangeError, sparse_merkle_tree::SMTError, MerkleProofError};
 use tari_storage::lmdb_store::LMDBError;
 use thiserror::Error;
@@ -139,6 +139,8 @@ pub enum ChainStorageError {
     FromKeyBytesFailed(String),
     #[error("Sparse Merkle Tree error: {0}")]
     SMTError(#[from] SMTError),
+    #[error("Invalid ChainMetaData: {0}")]
+    InvalidChainMetaData(#[from] ChainMetaDataError),
 }
 
 impl ChainStorageError {
@@ -190,6 +192,7 @@ impl ChainStorageError {
             _err @ ChainStorageError::FixedHashSizeError(_) |
             _err @ ChainStorageError::CompositeKeyLengthExceeded |
             _err @ ChainStorageError::FromKeyBytesFailed(_) |
+            _err @ ChainStorageError::InvalidChainMetaData(_) |
             _err @ ChainStorageError::OutOfRange => None,
         }
     }

base_layer/core/src/chain_storage/lmdb_db/lmdb_db.rs

@@ -2449,7 +2449,7 @@ fn fetch_metadata(txn: &ConstTransaction<'_>, db: &Database) -> Result<ChainMeta
         fetch_pruned_height(txn, db)?,
         fetch_accumulated_work(txn, db)?,
         fetch_best_block_timestamp(txn, db)?,
-    ))
+    )?)
 }
 
 // Fetches the chain height from the provided metadata db.

base_layer/core/tests/tests/node_state_machine.rs

@@ -304,7 +304,7 @@ async fn test_event_channel() {
 
     let node_identity = random_node_identity();
     let block_hash = Blake2b::<U32>::digest(node_identity.node_id().as_bytes()).into();
-    let metadata = ChainMetadata::new(10, block_hash, 2800, 0, 5000.into(), 0);
+    let metadata = ChainMetadata::new(10, block_hash, 2800, 0, 5000.into(), 0).unwrap();
 
     node.comms
         .peer_manager()

base_layer/wallet/tests/support/base_node_service_mock.rs

@@ -79,7 +79,7 @@ impl MockBaseNodeService {
     pub fn set_base_node_state(&mut self, height: Option<u64>) {
         let (chain_metadata, is_synced) = match height {
             Some(height) => {
-                let metadata = ChainMetadata::new(height, FixedHash::zero(), 0, 0, 0.into(), 0);
+                let metadata = ChainMetadata::new(height, FixedHash::zero(), 0, 0, 1.into(), 0).unwrap();
                 (Some(metadata), Some(true))
             },
             None => (None, None),
@@ -95,7 +95,7 @@ impl MockBaseNodeService {
     }
 
     pub fn set_default_base_node_state(&mut self) {
-        let metadata = ChainMetadata::new(i64::MAX as u64, FixedHash::zero(), 0, 0, 0.into(), 0);
+        let metadata = ChainMetadata::new(i64::MAX as u64, FixedHash::zero(), 0, 0, 1.into(), 0).unwrap();
         self.state = BaseNodeState {
             node_id: None,
             chain_metadata: Some(metadata),

base_layer/wallet/tests/transaction_service_tests/service.rs

@@ -195,7 +195,7 @@ async fn setup_transaction_service<P: AsRef<Path>>(
 
     let passphrase = SafePassword::from("My lovely secret passphrase");
     let db = WalletDatabase::new(WalletSqliteDatabase::new(db_connection.clone(), passphrase).unwrap());
-    let metadata = ChainMetadata::new(std::i64::MAX as u64, FixedHash::zero(), 0, 0, 0.into(), 0);
+    let metadata = ChainMetadata::new(std::i64::MAX as u64, FixedHash::zero(), 0, 0, 1.into(), 0).unwrap();
 
     db.set_chain_metadata(metadata).unwrap();
 

base_layer/wallet_ffi/src/callback_handler_tests.rs

@@ -507,7 +507,8 @@ mod test {
             0,
             123.into(),
             ts_now.timestamp_millis() as u64,
-        );
+        )
+        .unwrap();
 
         base_node_event_sender
             .send(Arc::new(BaseNodeEvent::BaseNodeStateChanged(BaseNodeState {