Remove duplicated hash helpers

Author: stanislav-tkach

rust/rbac-registration/src/cardano/cip509/cip509.rs

@@ -470,7 +470,7 @@ fn decode_input_hash(
     };
 
     let len = bytes.len();
-    if let Ok(v) = TxInputHash::try_from(bytes) {
+    if let Ok(v) = TxInputHash::try_from(bytes.as_slice()) {
         Some(v)
     } else {
         report.invalid_value(

rust/rbac-registration/src/cardano/cip509/types/tx_input_hash.rs

@@ -1,41 +1,33 @@
 //! Transaction input hash type
 
+use anyhow::Context;
+use cardano_blockchain_types::hashes::Blake2b128Hash;
+
 /// A 16-byte hash of the transaction inputs field.
 ///
 /// This type is described [here].
 ///
 /// [here]: https://github.com/input-output-hk/catalyst-CIPs/blob/x509-envelope-metadata/CIP-XXXX/README.md#key-1-txn-inputs-hash
-#[derive(Debug, PartialEq, Clone, Default)]
-pub struct TxInputHash([u8; 16]);
+#[derive(Debug, PartialEq, Clone)]
+pub struct TxInputHash(Blake2b128Hash);
 
 impl From<[u8; 16]> for TxInputHash {
     fn from(bytes: [u8; 16]) -> Self {
-        TxInputHash(bytes)
+        Self(Blake2b128Hash::from(bytes))
     }
 }
 
-impl TryFrom<Vec<u8>> for TxInputHash {
-    type Error = &'static str;
-
-    fn try_from(vec: Vec<u8>) -> Result<Self, Self::Error> {
-        if vec.len() == 16 {
-            let mut array = [0u8; 16];
-            array.copy_from_slice(&vec);
-            Ok(TxInputHash(array))
-        } else {
-            Err("Input Vec must be exactly 16 bytes")
-        }
-    }
-}
+impl TryFrom<&[u8]> for TxInputHash {
+    type Error = anyhow::Error;
 
-impl From<TxInputHash> for Vec<u8> {
-    fn from(val: TxInputHash) -> Self {
-        val.0.to_vec()
+    fn try_from(value: &[u8]) -> Result<Self, Self::Error> {
+        let hash = Blake2b128Hash::try_from(value).context("Invalid transaction input hash")?;
+        Ok(Self(hash))
     }
 }
 
-impl From<TxInputHash> for [u8; 16] {
-    fn from(val: TxInputHash) -> Self {
-        val.0
+impl From<Blake2b128Hash> for TxInputHash {
+    fn from(value: Blake2b128Hash) -> Self {
+        Self(value)
     }
 }

rust/rbac-registration/src/cardano/cip509/validation.rs

@@ -23,7 +23,10 @@
 
 use std::borrow::Cow;
 
-use cardano_blockchain_types::{TxnWitness, VKeyHash};
+use cardano_blockchain_types::{
+    hashes::{Blake2b128Hash, Blake2b256Hash},
+    TxnWitness, VKeyHash,
+};
 use catalyst_types::problem_report::ProblemReport;
 use pallas::{
     codec::{
@@ -34,10 +37,7 @@ use pallas::{
 };
 
 use super::utils::cip19::compare_key_hash;
-use crate::{
-    cardano::cip509::{types::TxInputHash, Cip0134UriSet, LocalRefInt, RoleData},
-    utils::hashing::{blake2b_128, blake2b_256},
-};
+use crate::cardano::cip509::{types::TxInputHash, Cip0134UriSet, LocalRefInt, RoleData};
 
 /// Context-specific primitive type with tag number 6 (`raw_tag` 134) for
 /// uniform resource identifier (URI) in the subject alternative name extension.
@@ -77,24 +77,14 @@ pub fn validate_txn_inputs_hash(
         }
     }
 
-    match blake2b_128(&buffer).map(TxInputHash::from) {
-        Ok(h) if h == *hash => {
-            // All good - the calculated hash is the same as in Cip509.
-        },
-        Ok(h) => {
-            report.invalid_value(
-                "txn_inputs_hash",
-                &format!("{h:?}"),
-                &format!("Must be equal to the value in Cip509 ({hash:?})"),
-                context,
-            );
-        },
-        Err(e) => {
-            report.other(
-                &format!("Failed to hash transaction inputs: {e:?}"),
-                context,
-            );
-        },
+    let calculated_hash = TxInputHash::from(Blake2b128Hash::new(&buffer));
+    if &calculated_hash != hash {
+        report.invalid_value(
+            "txn_inputs_hash",
+            &format!("{hash:?}"),
+            &format!("Must be equal to the value in Cip509 ({hash:?})"),
+            context,
+        );
     }
 }
 
@@ -108,23 +98,23 @@ pub fn validate_aux(
         report.other("Auxiliary data hash not found in transaction", context);
         return;
     };
-
-    match blake2b_256(auxiliary_data) {
-        Ok(h) if h == ***auxiliary_data_hash => {
-            // The hash is correct.
-        },
-        Ok(h) => {
-            report.other(
-                &format!("Incorrect transaction auxiliary data hash = '{h:?}', expected = '{auxiliary_data_hash:?}'"),
-                context,
-            );
-        },
+    let auxiliary_data_hash = match Blake2b256Hash::try_from(auxiliary_data_hash.as_slice()) {
+        Ok(v) => v,
         Err(e) => {
             report.other(
-                &format!("Failed to hash transaction auxiliary data: {e:?}"),
+                &format!("Invalid transaction auxiliary data hash: {e:?}"),
                 context,
             );
+            return;
         },
+    };
+
+    let hash = Blake2b256Hash::new(auxiliary_data);
+    if hash != auxiliary_data_hash {
+        report.other(
+            &format!("Incorrect transaction auxiliary data hash = '{hash:?}', expected = '{auxiliary_data_hash:?}'"),
+            context,
+        );
     }
 }
 

rust/rbac-registration/src/utils/hashing.rs

@@ -1,8 +1,8 @@
 //! Utility functions for the RBAC registration module.
 
-pub(crate) mod decode_helper;
+pub mod decode_helper;
+// TODO: FIXME: Remove module or pub crate?
 pub(crate) mod general;
-pub(crate) mod hashing;
 
 #[cfg(test)]
 pub mod test;