Refactor the validators to ensure that each validation step only comp…

…letes once.

applications/tari_base_node/src/builder.rs

@@ -467,7 +467,7 @@ where
     let factories = CryptoFactories::default();
     let validators = Validators::new(
         FullConsensusValidator::new(rules.clone(), factories.clone()),
-        StatelessBlockValidator::new(&rules.consensus_constants()),
+        StatelessBlockValidator::new(rules.clone(), factories.clone()),
         AccumDifficultyValidator {},
     );
     let db_config = BlockchainDatabaseConfig {

base_layer/core/src/validation/block_validators.rs

@@ -45,27 +45,29 @@ pub const LOG_TARGET: &str = "c::val::block_validators";
 /// This validator tests whether a candidate block is internally consistent
 #[derive(Clone)]
 pub struct StatelessBlockValidator {
-    consensus_constants: ConsensusConstants,
+    rules: ConsensusManager,
+    factories: CryptoFactories,
 }
 
 impl StatelessBlockValidator {
-    pub fn new(consensus_constants: &ConsensusConstants) -> Self {
-        Self {
-            consensus_constants: consensus_constants.clone(),
-        }
+    pub fn new(rules: ConsensusManager, factories: CryptoFactories) -> Self {
+        Self { rules, factories }
     }
 }
 
 impl StatelessValidation<Block> for StatelessBlockValidator {
     /// The consensus checks that are done (in order of cheapest to verify to most expensive):
     /// 1. Is there precisely one Coinbase output and is it correctly defined?
+    /// 1. Is the block weight of the block under the prescribed limit?
+    /// 1. Does it contain only unique inputs and outputs?
+    /// 1. Where all the rules for the spent outputs followed?
+    /// 1. Was cut through applied in the block?
     /// 1. Is the accounting correct?
-    /// 1. Are all inputs allowed to be spent (Are the feature flags satisfied)
     fn validate(&self, block: &Block) -> Result<(), ValidationError> {
         let block_id = format!("block #{} ({})", block.header.height, block.hash().to_hex());
-        check_coinbase_output(block, &self.consensus_constants)?;
+        check_coinbase_output(block, &self.rules.consensus_constants())?;
         trace!(target: LOG_TARGET, "SV - Coinbase output is ok for {} ", &block_id);
-        check_block_weight(block, &self.consensus_constants)?;
+        check_block_weight(block, &self.rules.consensus_constants())?;
         trace!(target: LOG_TARGET, "SV - Block weight is ok for {} ", &block_id);
         // Check that the inputs are are allowed to be spent
         block.check_stxo_rules().map_err(BlockValidationError::from)?;
@@ -76,6 +78,9 @@ impl StatelessValidation<Block> for StatelessBlockValidator {
             target: LOG_TARGET,
             "{} has PASSED stateless VALIDATION check.", &block_id
         );
+
+        check_accounting_balance(block, self.rules.clone(), &self.factories)?;
+        trace!(target: LOG_TARGET, "SV - accounting balance correct for {}", &block_id);
         Ok(())
     }
 }
@@ -104,16 +109,6 @@ impl<B: BlockchainBackend> Validation<Block, B> for FullConsensusValidator {
     /// 1. Is the achieved difficulty of this block >= the target difficulty for this block?
     fn validate(&self, block: &Block, db: &B) -> Result<(), ValidationError> {
         let block_id = format!("block #{} ({})", block.header.height, block.hash().to_hex());
-        check_coinbase_output(block, &self.rules.consensus_constants())?;
-        trace!(target: LOG_TARGET, "FCV - Coinbase output ok for {}", &block_id);
-        check_block_weight(block, &self.rules.consensus_constants())?;
-        trace!(target: LOG_TARGET, "FCV - Block weight ok for {}", &block_id);
-        check_cut_through(block)?;
-        trace!(target: LOG_TARGET, "FCV - Cut-though correct for {}", &block_id);
-        block.check_stxo_rules().map_err(BlockValidationError::from)?;
-        trace!(target: LOG_TARGET, "FCV - Cut-though correct for {}", &block_id);
-        check_accounting_balance(block, self.rules.clone(), &self.factories)?;
-        trace!(target: LOG_TARGET, "FCV - Cut-though correct for {}", &block_id);
         check_inputs_are_utxos(block, db)?;
         trace!(target: LOG_TARGET, "FCV - All inputs are valid for {}", &block_id);
         check_mmr_roots(block, db)?;
@@ -134,13 +129,49 @@ impl<B: BlockchainBackend> Validation<Block, B> for FullConsensusValidator {
     }
 }
 
+/// This validator tests whether a candidate block is internally consistent, BUT it does not check internal accounting
+/// as some tests use odd values.
+#[derive(Clone)]
+pub struct MockStatelessBlockValidator {
+    rules: ConsensusManager,
+    factories: CryptoFactories,
+}
+
+impl MockStatelessBlockValidator {
+    pub fn new(rules: ConsensusManager, factories: CryptoFactories) -> Self {
+        Self { rules, factories }
+    }
+}
+
+impl StatelessValidation<Block> for MockStatelessBlockValidator {
+    /// The consensus checks that are done (in order of cheapest to verify to most expensive):
+    /// 1. Is there precisely one Coinbase output and is it correctly defined?
+    /// 1. Is the block weight of the block under the prescribed limit?
+    /// 1. Does it contain only unique inputs and outputs?
+    /// 1. Where all the rules for the spent outputs followed?
+    /// 1. Was cut through applied in the block?
+    fn validate(&self, block: &Block) -> Result<(), ValidationError> {
+        check_coinbase_output(block, &self.rules.consensus_constants())?;
+        check_block_weight(block, &self.rules.consensus_constants())?;
+        // Check that the inputs are are allowed to be spent
+        block.check_stxo_rules().map_err(BlockValidationError::from)?;
+        check_cut_through(block)?;
+
+        Ok(())
+    }
+}
+
 //-------------------------------------     Block validator helper functions     -------------------------------------//
 fn check_accounting_balance(
     block: &Block,
     rules: ConsensusManager,
     factories: &CryptoFactories,
 ) -> Result<(), ValidationError>
 {
+    if block.header.height == 0 {
+        // Gen block does not need to be checked for this.
+        return Ok(());
+    }
     let offset = &block.header.total_kernel_offset;
     let total_coinbase = rules.calculate_coinbase_and_fees(block);
     block

base_layer/core/tests/block_validation.rs

@@ -37,8 +37,8 @@ fn test_genesis_block() {
     let rules = ConsensusManagerBuilder::new(network).build();
     let backend = MemoryDatabase::<HashDigest>::default();
     let validators = Validators::new(
-        FullConsensusValidator::new(rules.clone(), factories),
-        StatelessBlockValidator::new(&rules.consensus_constants()),
+        FullConsensusValidator::new(rules.clone(), factories.clone()),
+        StatelessBlockValidator::new(rules.clone(), factories),
         AccumDifficultyValidator {},
     );
     let db = BlockchainDatabase::new(backend, &rules, validators, BlockchainDatabaseConfig::default()).unwrap();

base_layer/core/tests/chain_storage_tests/chain_storage.rs

@@ -60,7 +60,7 @@ use tari_core::{
     txn_schema,
     validation::{
         accum_difficulty_validators::MockAccumDifficultyValidator,
-        block_validators::StatelessBlockValidator,
+        block_validators::{MockStatelessBlockValidator, StatelessBlockValidator},
         mocks::MockValidator,
     },
 };
@@ -873,7 +873,7 @@ fn invalid_block() {
             .build();
         let validators = Validators::new(
             MockValidator::new(true),
-            StatelessBlockValidator::new(&consensus_manager.consensus_constants()),
+            MockStatelessBlockValidator::new(consensus_manager.clone(), factories.clone()),
             MockAccumDifficultyValidator {},
         );
         let db = create_lmdb_database(&temp_path, MmrCacheConfig::default()).unwrap();

base_layer/core/tests/node_service.rs

@@ -507,7 +507,7 @@ fn propagate_and_forward_invalid_block() {
         .with_consensus_constants(consensus_constants)
         .with_block(block0.clone())
         .build();
-    let stateless_block_validator = StatelessBlockValidator::new(&rules.consensus_constants());
+    let stateless_block_validator = StatelessBlockValidator::new(rules.clone(), factories.clone());
     let mock_validator = MockValidator::new(true);
     let mock_accum_difficulty_validator = MockAccumDifficultyValidator {};
     let (mut alice_node, rules) = BaseNodeBuilder::new(network)

base_layer/core/tests/node_state_machine.rs

@@ -65,7 +65,7 @@ use tari_core::{
     transactions::types::CryptoFactories,
     validation::{
         accum_difficulty_validators::MockAccumDifficultyValidator,
-        block_validators::StatelessBlockValidator,
+        block_validators::{MockStatelessBlockValidator, StatelessBlockValidator},
         mocks::MockValidator,
     },
 };
@@ -605,7 +605,7 @@ fn test_sync_peer_banning() {
         .with_consensus_constants(consensus_constants)
         .with_block(prev_block.clone())
         .build();
-    let stateless_block_validator = StatelessBlockValidator::new(consensus_manager.consensus_constants());
+    let stateless_block_validator = MockStatelessBlockValidator::new(consensus_manager.clone(), factories.clone());
     let mock_validator = MockValidator::new(true);
     // Create base nodes
     let alice_node_identity = random_node_identity();