fix: implement hashing api for dan layer (see issue #4392) (#4427)

Description
--- Add tari hashing api for DAN layer.

Motivation and Context
--- Tackle issue #4392.

How Has This Been Tested?
--- Existing unit tests.

dan_layer/core/src/models/hashing.rs

@@ -0,0 +1,42 @@
+// Copyright 2021. The Tari Project
+//
+// Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
+// following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following
+// disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
+// following disclaimer in the documentation and/or other materials provided with the distribution.
+//
+// 3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote
+// products derived from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+// INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+// 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 digest::Digest;
+use tari_crypto::{
+    hash_domain,
+    hashing::{DomainSeparatedHasher, LengthExtensionAttackResistant},
+};
+
+hash_domain!(
+    DanLayerCoreModelsDomain,
+    "com.tari.tari_project.dan_layer.core.models",
+    1
+);
+
+pub(crate) const HOT_STUFF_MESSAGE_LABEL: &str = "hot_stuff_message";
+pub(crate) const TARI_DAN_PAYLOAD_LABEL: &str = "tari_dan_payload";
+
+pub(crate) fn dan_layer_models_hasher<D: Digest + LengthExtensionAttackResistant>(
+    label: &'static str,
+) -> DomainSeparatedHasher<D, DanLayerCoreModelsDomain> {
+    DomainSeparatedHasher::<D, DanLayerCoreModelsDomain>::new_with_label(label)
+}

dan_layer/core/src/models/hot_stuff_message.rs

@@ -20,12 +20,13 @@
 // 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 digest::Digest;
 use tari_common_types::types::FixedHash;
 use tari_core::transactions::transaction_components::SignerSignature;
 use tari_crypto::hash::blake2::Blake256;
 
+use super::HOT_STUFF_MESSAGE_LABEL;
 use crate::models::{
+    dan_layer_models_hasher,
     HotStuffMessageType,
     HotStuffTreeNode,
     Payload,
@@ -200,7 +201,7 @@ impl<TPayload: Payload> HotStuffMessage<TPayload> {
     }
 
     pub fn create_signature_challenge(&self) -> Vec<u8> {
-        let mut b = Blake256::new()
+        let mut b = dan_layer_models_hasher::<Blake256>(HOT_STUFF_MESSAGE_LABEL)
             .chain(&[self.message_type.as_u8()])
             .chain(self.view_number.as_u64().to_le_bytes());
         if let Some(ref node) = self.node {
@@ -209,7 +210,7 @@ impl<TPayload: Payload> HotStuffMessage<TPayload> {
             b = b.chain(node_hash.as_bytes());
         } else {
         }
-        b.finalize().to_vec()
+        b.finalize().as_ref().to_vec()
     }
 
     pub fn view_number(&self) -> ViewId {

dan_layer/core/src/models/mod.rs

@@ -28,6 +28,7 @@ mod base_layer_output;
 mod committee;
 pub mod domain_events;
 mod error;
+mod hashing;
 mod hot_stuff_message;
 mod hot_stuff_tree_node;
 mod instruction_set;
@@ -46,6 +47,7 @@ pub use base_layer_metadata::BaseLayerMetadata;
 pub use base_layer_output::{BaseLayerOutput, CheckpointOutput, CommitteeOutput};
 pub use committee::Committee;
 pub use error::ModelError;
+pub(crate) use hashing::{dan_layer_models_hasher, HOT_STUFF_MESSAGE_LABEL};
 pub use hot_stuff_message::HotStuffMessage;
 pub use hot_stuff_tree_node::HotStuffTreeNode;
 pub use instruction_set::InstructionSet;

dan_layer/core/src/models/tari_dan_payload.rs

@@ -22,11 +22,11 @@
 
 use std::fmt::Debug;
 
-use digest::Digest;
 use tari_common_types::types::FixedHash;
 use tari_crypto::hash::blake2::Blake256;
 use tari_dan_engine::instructions::Instruction;
 
+use super::{dan_layer_models_hasher, hashing::TARI_DAN_PAYLOAD_LABEL};
 use crate::models::{ConsensusHash, InstructionSet, Payload};
 
 #[derive(Debug, Clone)]
@@ -56,12 +56,19 @@ impl TariDanPayload {
     }
 
     fn calculate_hash(&self) -> FixedHash {
-        let result = Blake256::new().chain(self.instruction_set.consensus_hash());
-        if let Some(ref ck) = self.checkpoint {
-            result.chain(ck.consensus_hash()).finalize().into()
+        let result =
+            dan_layer_models_hasher::<Blake256>(TARI_DAN_PAYLOAD_LABEL).chain(self.instruction_set.consensus_hash());
+
+        let mut out = [0u8; 32];
+
+        let result = if let Some(ref ck) = self.checkpoint {
+            result.chain(ck.consensus_hash()).finalize()
         } else {
-            result.finalize().into()
-        }
+            result.finalize()
+        };
+
+        out.copy_from_slice(result.as_ref());
+        out.into()
     }
 }
 

dan_layer/core/src/templates/hashing.rs

@@ -0,0 +1,41 @@
+// Copyright 2021. The Tari Project
+//
+// Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
+// following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following
+// disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
+// following disclaimer in the documentation and/or other materials provided with the distribution.
+//
+// 3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote
+// products derived from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+// INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+// 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 digest::Digest;
+use tari_crypto::{
+    hash_domain,
+    hashing::{DomainSeparatedHasher, LengthExtensionAttackResistant},
+};
+
+hash_domain!(
+    DanLayerCoreTemplatesDomain,
+    "com.tari.tari_project.dan_layer.core.templates",
+    1
+);
+
+pub(crate) const TIP004_TEMPLATE_LABEL: &str = "tip004_template";
+
+pub(crate) fn dan_layer_templates_hasher<D: Digest + LengthExtensionAttackResistant>(
+    label: &'static str,
+) -> DomainSeparatedHasher<D, DanLayerCoreTemplatesDomain> {
+    DomainSeparatedHasher::<D, DanLayerCoreTemplatesDomain>::new_with_label(label)
+}

dan_layer/core/src/templates/mod.rs

@@ -20,6 +20,7 @@
 // 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.
 
+pub mod hashing;
 pub mod tip002_template;
 pub mod tip004_template;
 pub mod tip721_template;

dan_layer/core/src/templates/tip004_template.rs

@@ -20,7 +20,6 @@
 //  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 digest::Digest;
 use log::*;
 use prost::Message;
 use tari_core::transactions::transaction_components::TemplateParameter;
@@ -29,6 +28,7 @@ use tari_dan_common_types::proto::tips::tip004;
 use tari_dan_engine::state::{StateDbUnitOfWork, StateDbUnitOfWorkReader};
 use tari_utilities::hex::Hex;
 
+use super::hashing::{dan_layer_templates_hasher, TIP004_TEMPLATE_LABEL};
 use crate::{models::InstructionSet, DigitalAssetError};
 
 const LOG_TARGET: &str = "tari::dan_layer::core::templates::tip004_template";
@@ -95,7 +95,11 @@ fn mint<TUnitOfWork: StateDbUnitOfWork>(args: &[u8], state_db: &mut TUnitOfWork)
 }
 
 fn hash_of(s: &str) -> Vec<u8> {
-    Blake256::new().chain(s).finalize().to_vec()
+    dan_layer_templates_hasher::<Blake256>(TIP004_TEMPLATE_LABEL)
+        .chain(s)
+        .finalize()
+        .as_ref()
+        .to_vec()
 }
 
 fn balance_of<TUnitOfWork: StateDbUnitOfWorkReader>(

dan_layer/engine/src/instructions/hashing.rs

@@ -0,0 +1,41 @@
+// Copyright 2021. The Tari Project
+//
+// Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
+// following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following
+// disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
+// following disclaimer in the documentation and/or other materials provided with the distribution.
+//
+// 3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote
+// products derived from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+// INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+// 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 digest::Digest;
+use tari_crypto::{
+    hash_domain,
+    hashing::{DomainSeparatedHasher, LengthExtensionAttackResistant},
+};
+
+hash_domain!(
+    DanLayerEngineInstructionsDomain,
+    "com.tari.tari_project.dan_layer.engine.instructions",
+    1
+);
+
+pub(crate) const INSTRUCTION_LABEL: &str = "instruction";
+
+pub(crate) fn dan_layer_engine_instructions<D: Digest + LengthExtensionAttackResistant>(
+    label: &'static str,
+) -> DomainSeparatedHasher<D, DanLayerEngineInstructionsDomain> {
+    DomainSeparatedHasher::<D, DanLayerEngineInstructionsDomain>::new_with_label(label)
+}

dan_layer/engine/src/instructions/instruction.rs

@@ -3,12 +3,13 @@
 
 use std::fmt::{Display, Formatter};
 
-use digest::Digest;
 use tari_common_types::types::{FixedHash, PublicKey};
 use tari_crypto::hash::blake2::Blake256;
 use tari_dan_common_types::TemplateId;
 use tari_utilities::hex::Hex;
 
+use super::hashing::{dan_layer_engine_instructions, INSTRUCTION_LABEL};
+
 #[derive(Clone, Debug)]
 pub struct Instruction {
     template_id: TemplateId,
@@ -79,10 +80,16 @@ impl Instruction {
     }
 
     pub fn calculate_hash(&self) -> FixedHash {
-        let b = Blake256::new().chain(self.method.as_bytes()).chain(&self.args);
-        // b.chain(self.from.as_bytes())
-        //     .chain(com_sig_to_bytes(&self.signature))
-        b.finalize().into()
+        // Blake256 has 32-byte output
+        let b = dan_layer_engine_instructions::<Blake256>(INSTRUCTION_LABEL)
+            .chain(self.method.as_bytes())
+            .chain(&self.args)
+            .finalize();
+
+        let mut out = [0u8; 32];
+        out.copy_from_slice(b.as_ref());
+
+        out.into()
     }
 }
 

dan_layer/engine/src/instructions/mod.rs

@@ -1,6 +1,7 @@
 // Copyright 2022 The Tari Project
 // SPDX-License-Identifier: BSD-3-Clause
 
+mod hashing;
 mod instruction;
 
 pub use instruction::Instruction;