fix: merkle tree construction

Author: MarcosNicolau

aggregation_mode/aggregation_programs/risc0/src/lib.rs

@@ -42,9 +42,13 @@ impl IsMerkleTreeBackend for Risc0ImageIdAndPubInputs {
 
     fn hash_new_parent(child_1: &Self::Node, child_2: &Self::Node) -> Self::Node {
         let mut hasher = Keccak::v256();
-        hasher.update(child_1);
-        hasher.update(child_2);
-
+        if child_1 < child_2 {
+            hasher.update(child_1);
+            hasher.update(child_2);
+        } else {
+            hasher.update(child_2);
+            hasher.update(child_1);
+        }
         let mut hash = [0u8; 32];
         hasher.finalize(&mut hash);
         hash

aggregation_mode/aggregation_programs/sp1/src/lib.rs

@@ -39,8 +39,13 @@ impl IsMerkleTreeBackend for SP1VkAndPubInputs {
 
     fn hash_new_parent(child_1: &Self::Node, child_2: &Self::Node) -> Self::Node {
         let mut hasher = Keccak256::new();
-        hasher.update(child_1);
-        hasher.update(child_2);
+        if child_1 < child_2 {
+            hasher.update(child_1);
+            hasher.update(child_2);
+        } else {
+            hasher.update(child_2);
+            hasher.update(child_1);
+        }
         hasher.finalize().into()
     }
 }

aggregation_mode/src/aggregators/mod.rs

@@ -152,8 +152,13 @@ impl IsMerkleTreeBackend for AlignedProof {
 
     fn hash_new_parent(child_1: &Self::Node, child_2: &Self::Node) -> Self::Node {
         let mut hasher = Keccak256::new();
-        hasher.update(child_1);
-        hasher.update(child_2);
+        if child_1 < child_2 {
+            hasher.update(child_1);
+            hasher.update(child_2);
+        } else {
+            hasher.update(child_2);
+            hasher.update(child_1);
+        }
         hasher.finalize().into()
     }
 }

batcher/aligned-sdk/src/sdk/aggregation.rs

@@ -72,8 +72,13 @@ impl IsMerkleTreeBackend for Hash32 {
 
     fn hash_new_parent(child_1: &Self::Node, child_2: &Self::Node) -> Self::Node {
         let mut hasher = Keccak256::new();
-        hasher.update(child_1);
-        hasher.update(child_2);
+        if child_1 < child_2 {
+            hasher.update(child_1);
+            hasher.update(child_2);
+        } else {
+            hasher.update(child_2);
+            hasher.update(child_1);
+        }
         hasher.finalize().into()
     }
 }