chore!: do not use dynamic types in interfaces

l1-contracts/src/core/Rollup.sol

@@ -23,7 +23,7 @@ import {IVerifier} from "@aztec/core/interfaces/IVerifier.sol";
 import {
   FeeLib, FeeHeaderLib, FeeAssetValue, PriceLib
 } from "@aztec/core/libraries/rollup/FeeLib.sol";
-import {HeaderLib} from "@aztec/core/libraries/rollup/HeaderLib.sol";
+import {ProposedHeader} from "@aztec/core/libraries/rollup/ProposedHeaderLib.sol";
 import {
   AddressSnapshotLib,
   SnapshottedAddressSet
@@ -104,7 +104,7 @@ contract Rollup is IStaking, IValidatorSelection, IRollup, RollupCore {
    * @param _flags - The flags to validate
    */
   function validateHeader(
-    bytes calldata _header,
+    ProposedHeader calldata _header,
     CommitteeAttestation[] memory _attestations,
     bytes32 _digest,
     Timestamp _currentTime,
@@ -113,7 +113,7 @@ contract Rollup is IStaking, IValidatorSelection, IRollup, RollupCore {
   ) external override(IRollup) {
     ProposeLib.validateHeader(
       ValidateHeaderArgs({
-        header: HeaderLib.decode(_header),
+        header: _header,
         attestations: _attestations,
         digest: _digest,
         currentTime: _currentTime,
@@ -205,7 +205,7 @@ contract Rollup is IStaking, IValidatorSelection, IRollup, RollupCore {
     bytes32 tipArchive = rollupStore.blocks[pendingBlockNumber].archive;
     require(tipArchive == _archive, Errors.Rollup__InvalidArchive(tipArchive, _archive));
 
-    address proposer = ValidatorSelectionLib.getProposerAt(slot, slot.epochFromSlot());
+    address proposer = ValidatorSelectionLib.getProposerAt(slot);
     require(
       proposer == msg.sender, Errors.ValidatorSelection__InvalidProposer(proposer, msg.sender)
     );
@@ -638,9 +638,7 @@ contract Rollup is IStaking, IValidatorSelection, IRollup, RollupCore {
    * @return The address of the proposer
    */
   function getProposerAt(Timestamp _ts) public override(IValidatorSelection) returns (address) {
-    Slot slot = _ts.slotFromTimestamp();
-    Epoch epochNumber = slot.epochFromSlot();
-    return ValidatorSelectionLib.getProposerAt(slot, epochNumber);
+    return ValidatorSelectionLib.getProposerAt(_ts.slotFromTimestamp());
   }
 
   /**

l1-contracts/src/core/interfaces/IRollup.sol

@@ -11,6 +11,7 @@ import {
   FeeHeader, L1FeeData, ManaBaseFeeComponents
 } from "@aztec/core/libraries/rollup/FeeLib.sol";
 import {FeeAssetPerEthE9, EthValue, FeeAssetValue} from "@aztec/core/libraries/rollup/FeeLib.sol";
+import {ProposedHeader} from "@aztec/core/libraries/rollup/ProposedHeaderLib.sol";
 import {ProposeArgs} from "@aztec/core/libraries/rollup/ProposeLib.sol";
 import {Timestamp, Slot, Epoch} from "@aztec/core/libraries/TimeLib.sol";
 import {IRewardDistributor} from "@aztec/governance/interfaces/IRewardDistributor.sol";
@@ -143,7 +144,7 @@ interface IRollupCore {
 
 interface IRollup is IRollupCore {
   function validateHeader(
-    bytes calldata _header,
+    ProposedHeader calldata _header,
     CommitteeAttestation[] memory _attestations,
     bytes32 _digest,
     Timestamp _currentTime,

l1-contracts/src/core/libraries/Errors.sol

@@ -82,7 +82,7 @@ library Errors {
   error Rollup__ManaLimitExceeded();
   error Rollup__RewardsNotClaimable();
 
-  // HeaderLib
+  // ProposedHeaderLib
   error HeaderLib__InvalidHeaderSize(uint256 expected, uint256 actual); // 0xf3ccb247
   error HeaderLib__InvalidSlotNumber(Slot expected, Slot actual); // 0x09ba91ff
 

l1-contracts/src/core/libraries/rollup/ProposeLib.sol

@@ -17,7 +17,7 @@ import {Timestamp, Slot, Epoch, TimeLib} from "@aztec/core/libraries/TimeLib.sol
 import {ValidatorSelectionLib} from
   "@aztec/core/libraries/validator-selection/ValidatorSelectionLib.sol";
 import {BlobLib} from "./BlobLib.sol";
-import {Header, HeaderLib} from "./HeaderLib.sol";
+import {ProposedHeader, ProposedHeaderLib, StateReference} from "./ProposedHeaderLib.sol";
 import {STFLib} from "./STFLib.sol";
 
 struct ProposeArgs {
@@ -26,15 +26,15 @@ struct ProposeArgs {
   // It doesn't need to be in the proposed header as the values are not used in propose() and they are committed to
   // by the last archive and blobs hash.
   // It can be removed if the archiver can refer to world state for the updated roots.
-  bytes stateReference;
+  StateReference stateReference;
   OracleInput oracleInput;
-  bytes header;
+  ProposedHeader header;
   bytes32[] txHashes;
 }
 
 struct ProposePayload {
   bytes32 archive;
-  bytes stateReference;
+  StateReference stateReference;
   OracleInput oracleInput;
   bytes32 headerHash;
   bytes32[] txHashes;
@@ -58,7 +58,7 @@ struct InterimProposeValues {
  * @param flags - Flags specific to the execution, whether certain checks should be skipped
  */
 struct ValidateHeaderArgs {
-  Header header;
+  ProposedHeader header;
   CommitteeAttestation[] attestations;
   bytes32 digest;
   Timestamp currentTime;
@@ -97,8 +97,8 @@ library ProposeLib {
     (v.blobHashes, v.blobsHashesCommitment, v.blobPublicInputsHash) =
       BlobLib.validateBlobs(_blobInput, _checkBlob);
 
-    Header memory header = HeaderLib.decode(_args.header);
-    v.headerHash = HeaderLib.hash(_args.header);
+    ProposedHeader memory header = _args.header;
+    v.headerHash = ProposedHeaderLib.hash(_args.header);
 
     Epoch currentEpoch = Timestamp.wrap(block.timestamp).epochFromTimestamp();
     ValidatorSelectionLib.setupEpoch(currentEpoch);

l1-contracts/src/core/libraries/rollup/ProposedHeaderLib.sol

@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright 2024 Aztec Labs.
+pragma solidity >=0.8.27;
+
+import {Hash} from "@aztec/core/libraries/crypto/Hash.sol";
+
+import {Slot, Timestamp} from "@aztec/core/libraries/TimeLib.sol";
+import {SafeCast} from "@oz/utils/math/SafeCast.sol";
+
+struct AppendOnlyTreeSnapshot {
+  bytes32 root;
+  uint32 nextAvailableLeafIndex;
+}
+
+struct PartialStateReference {
+  AppendOnlyTreeSnapshot noteHashTree;
+  AppendOnlyTreeSnapshot nullifierTree;
+  AppendOnlyTreeSnapshot publicDataTree;
+}
+
+struct StateReference {
+  AppendOnlyTreeSnapshot l1ToL2MessageTree;
+  // Note: Can't use "partial" name here as in protocol specs because it is a reserved solidity keyword
+  PartialStateReference partialStateReference;
+}
+
+struct GasFees {
+  uint128 feePerDaGas;
+  uint128 feePerL2Gas;
+}
+
+struct ContentCommitment {
+  uint256 numTxs;
+  bytes32 blobsHash;
+  bytes32 inHash;
+  bytes32 outHash;
+}
+
+struct ProposedHeader {
+  bytes32 lastArchiveRoot;
+  ContentCommitment contentCommitment;
+  Slot slotNumber;
+  Timestamp timestamp;
+  address coinbase;
+  bytes32 feeRecipient;
+  GasFees gasFees;
+  uint256 totalManaUsed;
+}
+
+/**
+ * @title ProposedHeader Library
+ * @author Aztec Labs
+ * @notice Decoding and validating a proposed L2 block header
+ */
+library ProposedHeaderLib {
+  using SafeCast for uint256;
+
+  /**
+   * @notice  Hash the proposed header
+   *
+   * @dev     The hashing here MUST match what is in the proposed_block_header.ts
+   *
+   * @param _header The header to hash
+   *
+   * @return The hash of the header
+   */
+  function hash(ProposedHeader memory _header) internal pure returns (bytes32) {
+    return Hash.sha256ToField(
+      abi.encodePacked(
+        _header.lastArchiveRoot,
+        _header.contentCommitment.numTxs,
+        _header.contentCommitment.blobsHash,
+        _header.contentCommitment.inHash,
+        _header.contentCommitment.outHash,
+        _header.slotNumber,
+        Timestamp.unwrap(_header.timestamp).toUint64(),
+        _header.coinbase,
+        _header.feeRecipient,
+        _header.gasFees.feePerDaGas,
+        _header.gasFees.feePerL2Gas,
+        _header.totalManaUsed
+      )
+    );
+  }
+}

l1-contracts/src/core/libraries/validator-selection/ValidatorSelectionLib.sol

@@ -165,18 +165,20 @@ library ValidatorSelectionLib {
     }
   }
 
-  function getProposerAt(Slot _slot, Epoch _epochNumber) internal returns (address) {
+  function getProposerAt(Slot _slot) internal returns (address) {
     // @note this is deliberately "bad" for the simple reason of code reduction.
     //       it does not need to actually return the full committee and then draw from it
     //       it can just return the proposer directly, but then we duplicate the code
     //       which we just don't have room for right now...
-    uint224 sampleSeed = getSampleSeed(_epochNumber);
-    address[] memory committee = sampleValidators(_epochNumber, sampleSeed);
+    Epoch epochNumber = _slot.epochFromSlot();
+
+    uint224 sampleSeed = getSampleSeed(epochNumber);
+    address[] memory committee = sampleValidators(epochNumber, sampleSeed);
     if (committee.length == 0) {
       return address(0);
     }
 
-    return committee[computeProposerIndex(_epochNumber, _slot, sampleSeed, committee.length)];
+    return committee[computeProposerIndex(epochNumber, _slot, sampleSeed, committee.length)];
   }
 
   /**

l1-contracts/test/MultiProof.t.sol

@@ -63,8 +63,9 @@ contract MultiProofTest is RollupBase {
   modifier setUpFor(string memory _name) {
     {
       DecoderBase.Full memory full = load(_name);
-      uint256 slotNumber = full.block.decodedHeader.slotNumber;
-      uint256 initialTime = full.block.decodedHeader.timestamp - slotNumber * SLOT_DURATION;
+      uint256 slotNumber = Slot.unwrap(full.block.header.slotNumber);
+      uint256 initialTime =
+        Timestamp.unwrap(full.block.header.timestamp) - slotNumber * SLOT_DURATION;
       vm.warp(initialTime);
     }