Add status byte to final digest (#9310)

ethereum-optimism · Feb 2, 2024 · ab6e51d · ab6e51d
1 parent 0872e3e
commit ab6e51d
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Showing 5 changed files with 15 additions and 5 deletions.
diff --git a/op-bindings/bindings/alphabetvm.go b/op-bindings/bindings/alphabetvm.go
diff --git a/op-bindings/bindings/preimageoracle.go b/op-bindings/bindings/preimageoracle.go
diff --git a/op-bindings/bindings/preimageoracle_more.go b/op-bindings/bindings/preimageoracle_more.go
diff --git a/packages/contracts-bedrock/src/cannon/PreimageOracle.sol b/packages/contracts-bedrock/src/cannon/PreimageOracle.sol
@@ -595,6 +595,9 @@ contract PreimageOracle is IPreimageOracle {
         LibKeccak.absorb(_stateMatrix, _postState.input);
         LibKeccak.permutation(_stateMatrix);
         bytes32 finalDigest = LibKeccak.squeeze(_stateMatrix);
+        assembly {
+            finalDigest := or(and(finalDigest, not(shl(248, 0xFF))), shl(248, 0x02))
+        }
 
         // Write the preimage part to the authorized preimage parts mapping.
         uint256 partOffset = metaData.partOffset();

diff --git a/packages/contracts-bedrock/test/cannon/PreimageOracle.t.sol b/packages/contracts-bedrock/test/cannon/PreimageOracle.t.sol
@@ -411,7 +411,7 @@ contract PreimageOracle_LargePreimageProposals_Test is Test {
             _postStateProof: postProof
         });
 
-        bytes32 finalDigest = keccak256(data);
+        bytes32 finalDigest = _setStatusByte(keccak256(data), 2);
         bytes32 expectedPart = bytes32((~uint256(0) & ~(uint256(type(uint64).max) << 192)) | (data.length << 192));
         assertTrue(oracle.preimagePartOk(finalDigest, 0));
         assertEq(oracle.preimageLengths(finalDigest), data.length);
@@ -727,7 +727,7 @@ contract PreimageOracle_LargePreimageProposals_Test is Test {
 
         // Validate the preimage part
         {
-            bytes32 finalDigest = keccak256(data);
+            bytes32 finalDigest = _setStatusByte(keccak256(data), 2);
             bytes32 expectedPart;
             assembly {
                 switch lt(_partOffset, 0x08)
@@ -1269,3 +1269,10 @@ contract PreimageOracle_LargePreimageProposals_Test is Test {
         (root_, proof_) = abi.decode(vm.ffi(commands), (bytes32, bytes32[]));
     }
 }
+
+/// @notice Sets the status byte of a hash.
+function _setStatusByte(bytes32 _hash, uint8 _status) pure returns (bytes32 out_) {
+    assembly {
+        out_ := or(and(not(shl(248, 0xFF)), _hash), shl(248, _status))
+    }
+}