feat: remove hash_digest type (#4376)

Description
---
Removed `HashDigest` type and replaced it directly with `Blake256`

Motivation and Context
---
Simplify code - this was also conflicting with `Challenge` type

How Has This Been Tested?
---
Unit tests - no functional changes

base_layer/common_types/src/types/bullet_rangeproofs.rs

@@ -32,14 +32,14 @@ use serde::{
 };
 use tari_utilities::{hex::*, ByteArray, ByteArrayError, Hashable};
 
-use crate::types::HashDigest;
+use crate::types::Blake256;
 
 #[derive(Debug, Default, Clone, PartialEq, Eq, PartialOrd, Ord)]
 pub struct BulletRangeProof(pub Vec<u8>);
 /// Implement the hashing function for RangeProof for use in the MMR
 impl Hashable for BulletRangeProof {
     fn hash(&self) -> Vec<u8> {
-        HashDigest::new().chain(&self.0).finalize().to_vec()
+        Blake256::new().chain(&self.0).finalize().to_vec()
     }
 }
 

base_layer/common_types/src/types/fixed_hash.rs

@@ -30,7 +30,7 @@ use digest::{consts::U32, generic_array, Digest};
 use serde::{Deserialize, Serialize};
 use tari_utilities::hex::{Hex, HexError};
 
-use crate::types::HashDigest;
+use crate::types::Blake256;
 
 const ZERO_HASH: [u8; FixedHash::byte_size()] = [0u8; FixedHash::byte_size()];
 
@@ -57,7 +57,7 @@ impl FixedHash {
     /// Hashes the bytes and returns the resulting `FixedHash`. Generally only be used as a convenience function for
     /// tests.
     pub fn hash_bytes<T: AsRef<[u8]>>(bytes: T) -> Self {
-        HashDigest::default().chain(bytes).finalize().into()
+        Blake256::default().chain(bytes).finalize().into()
     }
 }
 

base_layer/common_types/src/types/mod.rs

@@ -61,16 +61,13 @@ pub type BlindingFactor = RistrettoSecretKey;
 /// Define the hash function that will be used to produce a signature challenge
 pub type SignatureHasher = Blake256;
 
-/// Specify the Hash function for general hashing
-pub type HashDigest = Blake256;
-
 /// Specify the digest type for signature challenges
 pub type Challenge = Blake256;
 
 /// The type of output that `Challenge` produces
 pub type MessageHash = Vec<u8>;
 
-/// Define the data type that is used to store results of `HashDigest`
+/// Define the data type that is used to store results of a hash output
 pub type HashOutput = Vec<u8>;
 
 pub const RANGE_PROOF_BIT_LENGTH: usize = 64; // 2^64

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

@@ -31,10 +31,11 @@ use std::{
 use croaring::Bitmap;
 use futures::{stream::FuturesUnordered, StreamExt};
 use log::*;
-use tari_common_types::types::{Commitment, HashDigest, RangeProofService};
+use tari_common_types::types::{Commitment, RangeProofService};
 use tari_comms::{connectivity::ConnectivityRequester, peer_manager::NodeId};
 use tari_crypto::{
     commitment::HomomorphicCommitment,
+    hash::blake2::Blake256,
     tari_utilities::{hex::Hex, Hashable},
 };
 use tari_mmr::{MerkleMountainRange, MutableMmr};
@@ -325,7 +326,7 @@ impl<'a, B: BlockchainBackend + 'static> HorizonStateSynchronization<'a, B> {
                     .fetch_block_accumulated_data(current_header.header().prev_hash.clone())
                     .await?;
                 let kernel_pruned_set = block_data.dissolve().0;
-                let mut kernel_mmr = MerkleMountainRange::<HashDigest, _>::new(kernel_pruned_set);
+                let mut kernel_mmr = MerkleMountainRange::<Blake256, _>::new(kernel_pruned_set);
 
                 for hash in kernel_hashes.drain(..) {
                     kernel_mmr.push(hash)?;
@@ -486,8 +487,8 @@ impl<'a, B: BlockchainBackend + 'static> HorizonStateSynchronization<'a, B> {
             .await?;
         let (_, output_pruned_set, witness_pruned_set, _) = block_data.dissolve();
 
-        let mut output_mmr = MerkleMountainRange::<HashDigest, _>::new(output_pruned_set);
-        let mut witness_mmr = MerkleMountainRange::<HashDigest, _>::new(witness_pruned_set);
+        let mut output_mmr = MerkleMountainRange::<Blake256, _>::new(output_pruned_set);
+        let mut witness_mmr = MerkleMountainRange::<Blake256, _>::new(witness_pruned_set);
         let mut constants = self.rules.consensus_constants(current_header.height()).clone();
         let mut last_sync_timer = Instant::now();
         let mut avg_latency = RollingAverageTime::new(20);
@@ -595,7 +596,7 @@ impl<'a, B: BlockchainBackend + 'static> HorizonStateSynchronization<'a, B> {
                     bitmap.run_optimize();
 
                     let pruned_output_set = output_mmr.get_pruned_hash_set()?;
-                    let output_mmr = MutableMmr::<HashDigest, _>::new(pruned_output_set.clone(), bitmap.clone())?;
+                    let output_mmr = MutableMmr::<Blake256, _>::new(pruned_output_set.clone(), bitmap.clone())?;
 
                     let mmr_root = output_mmr.get_merkle_root()?;
                     if mmr_root != current_header.header().output_mr {

base_layer/core/src/blocks/block_header.rs

@@ -57,8 +57,9 @@ use serde::{
 };
 use tari_common_types::{
     array::{copy_into_fixed_array, copy_into_fixed_array_lossy},
-    types::{BlindingFactor, BlockHash, HashDigest, BLOCK_HASH_LENGTH},
+    types::{BlindingFactor, BlockHash, BLOCK_HASH_LENGTH},
 };
+use tari_crypto::hash::blake2::Blake256;
 use tari_utilities::{epoch_time::EpochTime, hex::Hex, ByteArray, Hashable};
 use thiserror::Error;
 
@@ -219,7 +220,7 @@ impl BlockHeader {
     pub fn merged_mining_hash(&self) -> Vec<u8> {
         if self.version <= 2 {
             // TODO: Remove deprecated header hashing #testnetreset
-            HashDigest::new()
+            Blake256::new()
                 .chain(self.version.to_le_bytes())
                 .chain(self.height.to_le_bytes())
                 .chain(self.prev_hash.as_bytes())
@@ -295,7 +296,7 @@ impl From<NewBlockHeaderTemplate> for BlockHeader {
 impl Hashable for BlockHeader {
     fn hash(&self) -> Vec<u8> {
         if self.version <= 2 {
-            HashDigest::new()
+            Blake256::new()
                 .chain(self.merged_mining_hash())
                 .chain(self.pow.to_bytes())
                 .chain(self.nonce.to_le_bytes())

base_layer/core/src/blocks/genesis_block.rs

@@ -192,17 +192,17 @@ pub fn get_dibbler_genesis_block() -> ChainBlock {
     // NB: `dibbler_genesis_sanity_check` must pass
 
     // use croaring::Bitmap;
-    // use tari_common_types::types::HashDigest;
     // use tari_mmr::{MerkleMountainRange, MutableMmr};
+    // use tari_crypto::hash::blake2::Blake256;
     //
-    // let mut kernel_mmr = MerkleMountainRange::<HashDigest, _>::new(Vec::new());
+    // let mut kernel_mmr = MerkleMountainRange::<Blake256, _>::new(Vec::new());
     // for k in block.body.kernels() {
     //     println!("k: {}", k);
     //     kernel_mmr.push(k.hash()).unwrap();
     // }
     //
-    // let mut witness_mmr = MerkleMountainRange::<HashDigest, _>::new(Vec::new());
-    // let mut output_mmr = MutableMmr::<HashDigest, _>::new(Vec::new(), Bitmap::create()).unwrap();
+    // let mut witness_mmr = MerkleMountainRange::<Blake256, _>::new(Vec::new());
+    // let mut output_mmr = MutableMmr::<Blake256, _>::new(Vec::new(), Bitmap::create()).unwrap();
     //
     // for o in block.body.outputs() {
     //     witness_mmr.push(o.witness_hash()).unwrap();
@@ -316,7 +316,8 @@ fn get_dibbler_genesis_block_raw() -> Block {
 #[cfg(test)]
 mod test {
     use croaring::Bitmap;
-    use tari_common_types::types::{Commitment, HashDigest};
+    use tari_common_types::types::Commitment;
+    use tari_crypto::hash::blake2::Blake256;
     use tari_mmr::{MerkleMountainRange, MutableMmr};
 
     use super::*;
@@ -360,13 +361,13 @@ mod test {
             .any(|k| k.features.contains(KernelFeatures::COINBASE_KERNEL)));
 
         // Check MMR
-        let mut kernel_mmr = MerkleMountainRange::<HashDigest, _>::new(Vec::new());
+        let mut kernel_mmr = MerkleMountainRange::<Blake256, _>::new(Vec::new());
         for k in block.block().body.kernels() {
             kernel_mmr.push(k.hash()).unwrap();
         }
 
-        let mut witness_mmr = MerkleMountainRange::<HashDigest, _>::new(Vec::new());
-        let mut output_mmr = MutableMmr::<HashDigest, _>::new(Vec::new(), Bitmap::create()).unwrap();
+        let mut witness_mmr = MerkleMountainRange::<Blake256, _>::new(Vec::new());
+        let mut output_mmr = MutableMmr::<Blake256, _>::new(Vec::new(), Bitmap::create()).unwrap();
 
         for o in block.block().body.outputs() {
             witness_mmr.push(o.witness_hash()).unwrap();

base_layer/core/src/chain_storage/blockchain_database.rs

@@ -36,8 +36,9 @@ use log::*;
 use serde::{Deserialize, Serialize};
 use tari_common_types::{
     chain_metadata::ChainMetadata,
-    types::{BlockHash, Commitment, FixedHash, HashDigest, HashOutput, PublicKey, Signature},
+    types::{BlockHash, Commitment, FixedHash, HashOutput, PublicKey, Signature},
 };
+use tari_crypto::hash::blake2::Blake256;
 use tari_mmr::{pruned_hashset::PrunedHashSet, MerkleMountainRange, MutableMmr};
 use tari_utilities::{epoch_time::EpochTime, hex::Hex, ByteArray, Hashable};
 
@@ -1253,10 +1254,10 @@ pub fn calculate_mmr_roots<T: BlockchainBackend>(db: &T, block: &Block) -> Resul
             value: header.prev_hash.to_hex(),
         })?;
 
-    let mut kernel_mmr = MerkleMountainRange::<HashDigest, _>::new(kernels);
-    let mut output_mmr = MutableMmr::<HashDigest, _>::new(outputs, deleted)?;
-    let mut witness_mmr = MerkleMountainRange::<HashDigest, _>::new(range_proofs);
-    let mut input_mmr = MerkleMountainRange::<HashDigest, _>::new(PrunedHashSet::default());
+    let mut kernel_mmr = MerkleMountainRange::<Blake256, _>::new(kernels);
+    let mut output_mmr = MutableMmr::<Blake256, _>::new(outputs, deleted)?;
+    let mut witness_mmr = MerkleMountainRange::<Blake256, _>::new(range_proofs);
+    let mut input_mmr = MerkleMountainRange::<Blake256, _>::new(PrunedHashSet::default());
 
     for kernel in body.kernels().iter() {
         kernel_mmr.push(kernel.hash())?;

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

@@ -538,16 +538,16 @@ impl Display for ContractIndexKey {
 
 #[cfg(test)]
 mod tests {
-    use digest::Digest;
-    use tari_common_types::types::HashDigest;
-
     use super::*;
     mod contract_index_key {
+        use blake2::Digest;
+        use tari_crypto::hash::blake2::Blake256;
+
         use super::*;
 
         #[test]
         fn it_represents_a_well_formed_contract_index_key() {
-            let hash = HashDigest::new().chain(b"foobar").finalize().into();
+            let hash = Blake256::new().chain(b"foobar").finalize().into();
             let key = ContractIndexKey::new(hash, OutputType::ContractCheckpoint);
             assert_eq!(key.as_lmdb_bytes()[0], KeyType::PerContract as u8);
             assert_eq!(key.as_lmdb_bytes()[1..33], *hash.as_slice());

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

@@ -46,8 +46,9 @@ use log::*;
 use serde::{Deserialize, Serialize};
 use tari_common_types::{
     chain_metadata::ChainMetadata,
-    types::{BlockHash, Commitment, FixedHash, HashDigest, HashOutput, PublicKey, Signature, BLOCK_HASH_LENGTH},
+    types::{BlockHash, Commitment, FixedHash, HashOutput, PublicKey, Signature, BLOCK_HASH_LENGTH},
 };
+use tari_crypto::hash::blake2::Blake256;
 use tari_mmr::{Hash, MerkleMountainRange, MutableMmr};
 use tari_storage::lmdb_store::{db, LMDBBuilder, LMDBConfig, LMDBStore};
 use tari_utilities::{
@@ -1281,7 +1282,7 @@ impl LMDBDatabase {
             ..
         } = data;
 
-        let mut kernel_mmr = MerkleMountainRange::<HashDigest, _>::new(pruned_kernel_set);
+        let mut kernel_mmr = MerkleMountainRange::<Blake256, _>::new(pruned_kernel_set);
 
         for kernel in kernels {
             total_kernel_sum = &total_kernel_sum + &kernel.excess;
@@ -1296,8 +1297,8 @@ impl LMDBDatabase {
             })?;
             self.insert_kernel(txn, &block_hash, &kernel, pos)?;
         }
-        let mut output_mmr = MutableMmr::<HashDigest, _>::new(pruned_output_set, Bitmap::create())?;
-        let mut witness_mmr = MerkleMountainRange::<HashDigest, _>::new(pruned_proof_set);
+        let mut output_mmr = MutableMmr::<Blake256, _>::new(pruned_output_set, Bitmap::create())?;
+        let mut witness_mmr = MerkleMountainRange::<Blake256, _>::new(pruned_proof_set);
 
         let leaf_count = witness_mmr.get_leaf_count()?;
 
@@ -2729,7 +2730,7 @@ impl UniqueIdIndexKey {
     /// `parent_public_key` - the parent asset public key to which the token is assigned
     /// `unique_id` - a series of bytes representing the token uniquely for the asset
     pub fn new(parent_public_key: Option<&PublicKey>, unique_id: &[u8]) -> Self {
-        let unique_id_hash = HashDigest::default().chain(unique_id).finalize();
+        let unique_id_hash = Blake256::default().chain(unique_id).finalize();
         Self::from_raw_parts(
             parent_public_key.map(|p| p.as_bytes()).unwrap_or(&[0; 32][..]),
             &unique_id_hash,

base_layer/core/src/consensus/consensus_encoding/hashing.rs

@@ -23,8 +23,10 @@
 use std::{io, io::Write, marker::PhantomData};
 
 use digest::{consts::U32, Digest};
-use tari_common_types::types::HashDigest;
-use tari_crypto::hashing::{DomainSeparatedHasher, DomainSeparation};
+use tari_crypto::{
+    hash::blake2::Blake256,
+    hashing::{DomainSeparatedHasher, DomainSeparation},
+};
 
 use crate::consensus::ConsensusEncoding;
 
@@ -33,7 +35,7 @@ pub struct DomainSeparatedConsensusHasher<M: DomainSeparation>(PhantomData<M>);
 
 impl<M: DomainSeparation> DomainSeparatedConsensusHasher<M> {
     #[allow(clippy::new_ret_no_self)]
-    pub fn new(label: &'static str) -> ConsensusHasher<DomainSeparatedHasher<HashDigest, M>> {
+    pub fn new(label: &'static str) -> ConsensusHasher<DomainSeparatedHasher<Blake256, M>> {
         ConsensusHasher::new(DomainSeparatedHasher::new_with_label(label))
     }
 }
@@ -70,9 +72,9 @@ where D: Digest<OutputSize = U32>
     }
 }
 
-impl Default for ConsensusHasher<HashDigest> {
+impl Default for ConsensusHasher<Blake256> {
     fn default() -> Self {
-        ConsensusHasher::new(HashDigest::new())
+        ConsensusHasher::new(Blake256::new())
     }
 }
 

base_layer/core/src/covenants/fields.rs

@@ -29,7 +29,7 @@ use std::{
 
 use digest::Digest;
 use integer_encoding::VarIntWriter;
-use tari_common_types::types::HashDigest;
+use tari_crypto::hash::blake2::Blake256;
 
 use crate::{
     consensus::ToConsensusBytes,
@@ -367,8 +367,8 @@ impl OutputFields {
         self.fields.is_empty()
     }
 
-    pub fn construct_challenge_from(&self, output: &TransactionOutput) -> HashDigest {
-        let mut challenge = HashDigest::new();
+    pub fn construct_challenge_from(&self, output: &TransactionOutput) -> Blake256 {
+        let mut challenge = Blake256::new();
         for field in &self.fields {
             challenge.update(field.get_field_value_bytes(output));
         }
@@ -596,7 +596,7 @@ mod test {
                 output.features.consensus_encode(&mut challenge).unwrap();
                 output.commitment.consensus_encode(&mut challenge).unwrap();
                 output.script.consensus_encode(&mut challenge).unwrap();
-                let expected_hash = HashDigest::new().chain(&challenge).finalize();
+                let expected_hash = Blake256::new().chain(&challenge).finalize();
                 assert_eq!(hash, expected_hash);
             }
         }

base_layer/core/src/mempool/unconfirmed_pool/unconfirmed_pool.rs

@@ -29,7 +29,8 @@ use std::{
 use digest::Digest;
 use log::*;
 use serde::{Deserialize, Serialize};
-use tari_common_types::types::{HashDigest, HashOutput, PrivateKey, PublicKey, Signature};
+use tari_common_types::types::{HashOutput, PrivateKey, PublicKey, Signature};
+use tari_crypto::hash::blake2::Blake256;
 use tari_utilities::{hex::Hex, ByteArray, Hashable};
 
 use crate::{
@@ -659,7 +660,7 @@ fn get_output_token_id(output: &TransactionOutput) -> Option<[u8; 32]> {
             .as_ref()
             .map(|pk| pk.as_bytes())
             .unwrap_or_else(|| root_pk.as_bytes());
-        HashDigest::new()
+        Blake256::new()
             .chain(parent_pk_bytes)
             .chain(unique_id)
             .finalize()
@@ -671,7 +672,6 @@ fn get_output_token_id(output: &TransactionOutput) -> Option<[u8; 32]> {
 mod test {
     use rand::rngs::OsRng;
     use tari_common::configuration::Network;
-    use tari_common_types::types::HashDigest;
     use tari_crypto::keys::PublicKey as PublicKeyTrait;
 
     use super::*;
@@ -788,7 +788,7 @@ mod test {
             .unwrap();
 
         let factories = CryptoFactories::default();
-        let mut stx_protocol = stx_builder.build::<HashDigest>(&factories, None, u64::MAX).unwrap();
+        let mut stx_protocol = stx_builder.build::<Blake256>(&factories, None, u64::MAX).unwrap();
         stx_protocol
             .finalize(KernelFeatures::empty(), &factories, None, u64::MAX)
             .unwrap();
@@ -1029,7 +1029,7 @@ mod test {
         unconfirmed_pool
             .insert_many(vec![tx1.clone(), tx2.clone(), tx3.clone(), tx4.clone()], &tx_weight)
             .unwrap();
-        let expected_hash: [u8; 32] = HashDigest::new()
+        let expected_hash: [u8; 32] = Blake256::new()
             .chain(parent_pk.as_bytes())
             .chain(&unique_id)
             .finalize()

base_layer/core/src/proto/types.proto

@@ -5,7 +5,7 @@ syntax = "proto3";
 
 package tari.types;
 
-// Define the data type that is used to store results of `HashDigest`
+// Define the data type that is used to store results of `Blake256`
 message HashOutput {
     bytes data = 1;
 }

base_layer/core/src/transactions/transaction_components/side_chain/contract_acceptance_challenge.rs

@@ -21,7 +21,8 @@
 //  USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 use digest::Digest;
-use tari_common_types::types::{Commitment, FixedHash, HashDigest};
+use tari_common_types::types::{Commitment, FixedHash};
+use tari_crypto::hash::blake2::Blake256;
 use tari_utilities::ByteArray;
 
 #[derive(Debug, Clone, Copy)]
@@ -30,7 +31,7 @@ pub struct ContractAcceptanceChallenge(FixedHash);
 impl ContractAcceptanceChallenge {
     pub fn new(constiution_commitment: &Commitment, contract_id: &FixedHash) -> Self {
         // TODO: Use new tari_crypto domain-separated hashing
-        let hash = HashDigest::new()
+        let hash = Blake256::new()
             .chain(constiution_commitment.as_bytes())
             .chain(contract_id.as_slice())
             .finalize()