Keep state buffer hashing processor-local

Avoid reaching into the already-reviewed fraud-proof processor for shared hashing. Each instruction now computes the same domain-separated payload hash locally, while only the commit/finalize transition shared by this stack remains under processor/internal.

Author: snawaz

program/src/processor/direct/commit_finalize_from_buffer.rs

@@ -10,11 +10,8 @@ use wheels::{
     layout::Decodable, require_eq, require_eq_keys, require_n_accounts,
 };
 
-use crate::processor::{
-    internal::{
-        apply_commit_finalize, CommitFinalizeInput, CommitStateUpdate,
-    },
-    state_buffer_payload_hash,
+use crate::processor::internal::{
+    apply_commit_finalize, CommitFinalizeInput, CommitStateUpdate,
 };
 
 /// Commit and apply one finalized StateBuffer for a Direct cluster.
@@ -148,9 +145,14 @@ fn validate_state_buffer(
     );
     require_eq!(
         buffer.data_hash(),
-        &state_buffer_payload_hash(buffer.payload().as_slice()),
+        &account_data_hash(buffer.payload().as_slice()),
         ProgramError::InvalidInstructionData
     );
 
     Ok(())
 }
+
+fn account_data_hash(data: &[u8]) -> [u8; 32] {
+    solana_sha256_hasher::hashv(&[b"magicblock.account_data.v1", data])
+        .to_bytes()
+}

program/src/processor/fraud_proofs/write_state_buffer.rs

@@ -16,7 +16,6 @@ use wheels::{
 
 use crate::{
     legacy::processor::fast::utils::pda::create_pda_with_rent_exempt_lamports,
-    processor::state_buffer_payload_hash,
     requires::{
         is_uninitialized_account, require_initialized_pda,
         require_uninitialized_pda, StandardCtx,
@@ -232,7 +231,7 @@ fn write_chunk(
             state.total_len() as usize,
             ProgramError::InvalidAccountData
         );
-        Some(state_buffer_payload_hash(payload.as_slice()))
+        Some(account_data_hash(payload.as_slice()))
     } else {
         None
     };
@@ -336,3 +335,8 @@ fn validate_duplicate_chunk(
 
     Ok(())
 }
+
+fn account_data_hash(data: &[u8]) -> [u8; 32] {
+    solana_sha256_hasher::hashv(&[b"magicblock.account_data.v1", data])
+        .to_bytes()
+}

program/src/processor/mod.rs

@@ -67,8 +67,3 @@ pub fn process_instruction(
         }
     }
 }
-
-pub(crate) fn state_buffer_payload_hash(payload: &[u8]) -> [u8; 32] {
-    solana_sha256_hasher::hashv(&[b"magicblock.account_data.v1", payload])
-        .to_bytes()
-}