✨ verifyBlockHash + toShortHeader

src/utils/BlockHashLib.sol

@@ -1,10 +1,26 @@
 // SPDX-License-Identifier: MIT
 pragma solidity ^0.8.4;
 
+/// @dev Ethereum block header fields relevant to historical MPT proofs.
+struct ShortHeader {
+    bytes32 parentHash;
+    bytes32 stateRoot;
+    bytes32 transactionsRoot;
+    bytes32 receiptsRoot;
+    bytes32[8] logsBloom;
+}
+
 /// @notice Library for accessing block hashes way beyond the 256-block limit.
 /// @author Solady (https://github.com/vectorized/solady/blob/main/src/utils/BlockHashLib.sol)
 /// @author Modified from OpenZeppelin (https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/Blockhash.sol)
 library BlockHashLib {
+    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
+    /*                       CUSTOM ERRORS                        */
+    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
+
+    /// @dev Invalid block hash.
+    error InvalidBlockHeader();
+
     /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
     /*                         CONSTANTS                          */
     /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
@@ -35,4 +51,46 @@ library BlockHashLib {
             result := mload(0x00)
         }
     }
+
+    /// @dev Returns whether the hash of a provided RLP-encoded block `header` equals the block hash at `blockNumber`.
+    function verifyBlockHash(bytes calldata header, uint256 blockNumber)
+        internal
+        view
+        returns (bytes32 result)
+    {
+        result = blockHash(blockNumber);
+        /// @solidity memory-safe-assembly
+        assembly {
+            calldatacopy(mload(0x40), header.offset, header.length)
+            if iszero(eq(result, keccak256(mload(0x40), header.length))) {
+                mstore(0x00, 0x464db2f8) // InvalidBlockHeader()
+                revert(0x1c, 0x04)
+            }
+        }
+    }
+
+    /// @dev Retrieves the most relevant fields for MPT proofs from an RLP-encoded block `header`.
+    /// Leading fields are always present and have fixed offsets and lengths.
+    /// This function allows efficient extraction of these fields from calldata without full RLP decoding.
+    /// For the specification of field order and lengths, please refer to prefix. 6 of the Ethereum Yellow Paper:
+    /// (https://ethereum.github.io/yellowpaper/paper.pdf)
+    /// and the Ethereum Wiki (https://epf.wiki/#/wiki/EL/RLP).
+    function toShortHeader(bytes calldata header)
+        internal
+        pure
+        returns (ShortHeader memory result)
+    {
+        /// @solidity memory-safe-assembly
+        assembly {
+            let m := mload(0x40)
+            let o := add(header.offset, sub(byte(0, calldataload(header.offset)), 0xF6))
+            mstore(result, calldataload(add(1, o))) // parentHash
+            mstore(add(0x20, result), calldataload(add(88, o))) // stateRoot
+            mstore(add(0x40, result), calldataload(add(121, o))) // transactionsRoot
+            mstore(add(0x60, result), calldataload(add(154, o))) // receiptsRoot
+            mstore(add(0x80, result), m) // logsBloom
+            calldatacopy(m, add(189, o), 0x100)
+            mstore(0x40, add(0x100, m)) // Allocate the memory.
+        }
+    }
 }

test/BlockHashLib.t.sol

@@ -2,7 +2,7 @@
 pragma solidity ^0.8.4;
 
 import "./utils/SoladyTest.sol";
-import {BlockHashLib} from "../src/utils/BlockHashLib.sol";
+import {BlockHashLib, ShortHeader} from "../src/utils/BlockHashLib.sol";
 
 contract BlockHashLibTest is SoladyTest {
     uint256 internal startingBlock;
@@ -12,6 +12,15 @@ contract BlockHashLibTest is SoladyTest {
     bytes private constant _HISTORY_STORAGE_BYTECODE =
         hex"3373fffffffffffffffffffffffffffffffffffffffe14604657602036036042575f35600143038111604257611fff81430311604257611fff9006545f5260205ff35b5f5ffd5b5f35611fff60014303065500";
 
+    // cast block 23270177  --raw
+    // vm.getRawBlockHeader(23270177)
+    bytes private constant _ETH_BLOCK_23270177 =
+        hex"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";
+
+    // keccak256(_ETH_BLOCK_23270177)
+    bytes32 private constant _ETH_BLOCK_HASH_23270177 =
+        0x5def79dc43d588fafa396f3fbf0bcfb9bf83eaf8003f4508a626b6d3e806b29f;
+
     function testBlockHash(
         uint256 simulationBlockNumber,
         uint256 queryBlockNumber,
@@ -57,4 +66,55 @@ contract BlockHashLibTest is SoladyTest {
             result := mload(0x00)
         }
     }
+
+    function beforeTestSetup(bytes4 selector) public pure returns (bytes[] memory cd) {
+        if (selector == this.testToShortHeader.selector) {
+            cd = new bytes[](1);
+            cd[0] = abi.encodeWithSelector(this.checkToShortHeader.selector, _ETH_BLOCK_23270177);
+        }
+        if (selector == this.testVerifyBlockHash.selector) {
+            cd = new bytes[](1);
+            cd[0] = abi.encodeWithSelector(this.checkVerifyBlockHash.selector, _ETH_BLOCK_23270177);
+        }
+    }
+
+    function checkToShortHeader(bytes calldata h) public {
+        ShortHeader memory expected = ShortHeader({
+            parentHash: 0x1581f4448b16694d5a728161cd65f8c80b88f5352a6f5bd2d2315b970582958d,
+            stateRoot: 0x10d2afa5dabcf2dbfe3aa82b758427938e07880bd6fef3c82c404d0dd7c3f0f3,
+            transactionsRoot: 0xf81230c715a462c827898bf2e337982907a7af90e5be20f911785bda05dab93c,
+            receiptsRoot: 0x740f11bc75cf25e40d78d892d2e03083eaa573e5b4c26913fcc1b833db854c94,
+            logsBloom: [
+                bytes32(0x85f734fb06ea8fe377abbcb2e27f9ac99751ba817dc327327db101fd76f964ed), // lol
+                0x0b7ca161f148fc165b9e5b575dc7473f17f4b8ebbf4a7b02b3e1e642197f27b2,
+                0xaf54680834449abaf833619ac7d18afb50b19d5f6944dca0dc952edfdd983757,
+                0x3783c339ee6a36353ce6e536eaaf29fcd569c426091d4e24568dc353347f98c7,
+                0x4fb6f8c91d68d358467c437563f66566377fe6c3f9e8301dbeb5fc7e7adee7a8,
+                0x5ef5f8fa905cedbaf26601e21ba91646cac4034601e51d889d49739ee6990943,
+                0xa6a41927660f68e1f50b9f9209ee29551a7dae478d88e0547eefc83334ea770b,
+                0xb6fbac620fc47479c2c59389622bf32f55e36a75e56a5fc47c38bf8ef211fc0e
+            ]
+        });
+
+        ShortHeader memory actual = BlockHashLib.toShortHeader(h);
+        assertEq(actual.parentHash, expected.parentHash, "parentHash");
+        assertEq(actual.stateRoot, expected.stateRoot, "stateRoot");
+        assertEq(actual.transactionsRoot, expected.transactionsRoot, "transactionsRoot");
+        assertEq(actual.receiptsRoot, expected.receiptsRoot, "receiptsRoot");
+        assertEq(
+            keccak256(abi.encodePacked(actual.logsBloom)),
+            keccak256(abi.encodePacked(expected.logsBloom)),
+            "logsBloom"
+        );
+    }
+
+    function checkVerifyBlockHash(bytes calldata h) public {
+        vm.roll(23270177 + 1);
+        vm.setBlockhash(23270177, _ETH_BLOCK_HASH_23270177);
+        assertEq(BlockHashLib.verifyBlockHash(h, 23270177), _ETH_BLOCK_HASH_23270177);
+    }
+
+    function testToShortHeader() public view {}
+
+    function testVerifyBlockHash() public view {}
 }