fix: block sync validation (#3236)

Description
---
This fixes the block sync block body validation to validate the correct items
This consolidates all the syncing helper functions
This adds in unit tests for the validators

Motivation and Context
---
Block sync needs to validate all the required steps. This also consolidates all the possible validation functions to remove duplicated pieces of code between the validators so we use a single piece to test a specific consensus item. 

How Has This Been Tested?
---
Synced a node up to the tip height 22014. 
Added new unit tests. 
Ran all integration and unit tests.

base_layer/core/src/base_node/sync/block_sync/synchronizer.rs

@@ -30,7 +30,7 @@ use crate::{
     proto::base_node::SyncBlocksRequest,
     tari_utilities::{hex::Hex, Hashable},
     transactions::aggregated_body::AggregateBody,
-    validation::CandidateBlockBodyValidation,
+    validation::BlockSyncBodyValidation,
 };
 use futures::StreamExt;
 use log::*;
@@ -55,7 +55,7 @@ pub struct BlockSynchronizer<B> {
     db: AsyncBlockchainDb<B>,
     connectivity: ConnectivityRequester,
     sync_peer: Option<PeerConnection>,
-    block_validator: Arc<dyn CandidateBlockBodyValidation<B>>,
+    block_validator: Arc<dyn BlockSyncBodyValidation<B>>,
     hooks: Hooks,
 }
 
@@ -65,7 +65,7 @@ impl<B: BlockchainBackend + 'static> BlockSynchronizer<B> {
         db: AsyncBlockchainDb<B>,
         connectivity: ConnectivityRequester,
         sync_peer: Option<PeerConnection>,
-        block_validator: Arc<dyn CandidateBlockBodyValidation<B>>,
+        block_validator: Arc<dyn BlockSyncBodyValidation<B>>,
     ) -> Self {
         Self {
             config,

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

@@ -28,22 +28,22 @@ use crate::{
     transactions::CryptoFactories,
     validation::{
         block_validators::BlockValidator,
-        CandidateBlockBodyValidation,
+        BlockSyncBodyValidation,
         ChainBalanceValidator,
         FinalHorizonStateValidation,
     },
 };
 
 #[derive(Clone)]
 pub struct SyncValidators<B: BlockchainBackend> {
-    pub block_body: Arc<dyn CandidateBlockBodyValidation<B>>,
+    pub block_body: Arc<dyn BlockSyncBodyValidation<B>>,
     pub final_horizon_state: Arc<dyn FinalHorizonStateValidation<B>>,
 }
 
 impl<B: BlockchainBackend + 'static> SyncValidators<B> {
     pub fn new<TBody, TFinal>(block_body: TBody, final_state: TFinal) -> Self
     where
-        TBody: CandidateBlockBodyValidation<B> + 'static,
+        TBody: BlockSyncBodyValidation<B> + 'static,
         TFinal: FinalHorizonStateValidation<B> + 'static,
     {
         Self {

base_layer/core/src/blocks/block.rs

@@ -55,6 +55,8 @@ pub enum BlockValidationError {
     TransactionError(#[from] TransactionError),
     #[error("Invalid input in block")]
     InvalidInput,
+    #[error("Contains kernels or inputs that are not yet spendable")]
+    MaturityError,
     #[error("Mismatched MMR roots")]
     MismatchedMmrRoots,
     #[error("MMR size for {mmr_tree} does not match. Expected: {expected}, received: {actual}")]
@@ -109,9 +111,12 @@ impl Block {
         Ok(())
     }
 
-    /// Checks that all STXO rules (maturity etc) are followed
-    pub fn check_stxo_rules(&self) -> Result<(), BlockValidationError> {
+    /// Checks that all STXO rules (maturity etc) and kernel heights are followed
+    pub fn check_spend_rules(&self) -> Result<(), BlockValidationError> {
         self.body.check_stxo_rules(self.header.height)?;
+        if self.body.max_kernel_timelock() > self.header.height {
+            return Err(BlockValidationError::MaturityError);
+        }
         Ok(())
     }
 

base_layer/core/src/transactions/aggregated_body.rs

@@ -1,14 +1,3 @@
-use std::fmt::{Display, Error, Formatter};
-
-use log::*;
-use serde::{Deserialize, Serialize};
-use tari_crypto::{
-    commitment::HomomorphicCommitmentFactory,
-    keys::PublicKey as PublicKeyTrait,
-    ristretto::pedersen::PedersenCommitment,
-    tari_utilities::hex::Hex,
-};
-
 // Copyright 2019, The Tari Project
 //
 // Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
@@ -31,6 +20,12 @@ use tari_crypto::{
 // WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
 // USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 use crate::transactions::{crypto_factories::CryptoFactories, fee::Fee, tari_amount::*, transaction::*};
+use log::*;
+use serde::{Deserialize, Serialize};
+use std::{
+    cmp::max,
+    fmt::{Display, Error, Formatter},
+};
 use tari_common_types::types::{
     BlindingFactor,
     Commitment,
@@ -39,6 +34,12 @@ use tari_common_types::types::{
     PublicKey,
     RangeProofService,
 };
+use tari_crypto::{
+    commitment::HomomorphicCommitmentFactory,
+    keys::PublicKey as PublicKeyTrait,
+    ristretto::pedersen::PedersenCommitment,
+    tari_utilities::hex::Hex,
+};
 
 pub const LOG_TARGET: &str = "c::tx::aggregated_body";
 
@@ -450,6 +451,12 @@ impl AggregateBody {
             self.kernels.len()
         )
     }
+
+    pub fn max_kernel_timelock(&self) -> u64 {
+        self.kernels()
+            .iter()
+            .fold(0, |max_timelock, kernel| max(max_timelock, kernel.lock_height))
+    }
 }
 
 /// This will strip away the offset of the transaction returning a pure aggregate body

base_layer/core/src/transactions/transaction.rs

@@ -1156,10 +1156,7 @@ impl Transaction {
 
     /// Returns the maximum time lock of the kernels inside of the transaction
     pub fn max_kernel_timelock(&self) -> u64 {
-        self.body
-            .kernels()
-            .iter()
-            .fold(0, |max_timelock, kernel| max(max_timelock, kernel.lock_height))
+        self.body.max_kernel_timelock()
     }
 
     /// Returns the height of the minimum height where the transaction is spendable. This is calculated from the