Adds EIP-2935 HISTORY_STORAGE contract support

builtin/builtin.go

@@ -36,6 +36,14 @@ var (
 	Staker  = &stakerContract{mustLoadContract("Staker")}
 	Measure = mustLoadContract("Measure")
 
+	// History is the EIP-2935 historical-block-hash facade. Its address is
+	// fixed by the EIP (not derived from the contract name) so dApps that
+	// already speak the EIP-2935 calling convention work unchanged on Thor.
+	History = &historyContract{mustLoadContractAt(
+		"History",
+		thor.MustParseAddress("0x0000F90827F1C53a10cb7A02335B175320002935"),
+	)}
+
 	// return gas map maintains the builtin contracts that can be made native call cheaper
 	// only the 0.4.24 compiled contracts are allowed to return gas, as the newer compiler
 	// versions have dynamic cost and pattern that is not predictable, any further added new
@@ -60,7 +68,8 @@ type (
 		V2 *contract
 		V3 *contract
 	}
-	stakerContract struct{ *contract }
+	stakerContract  struct{ *contract }
+	historyContract struct{ *contract }
 )
 
 func (p *paramsContract) Native(state *state.State) *params.Params {

builtin/contract.go

@@ -20,6 +20,13 @@ type contract struct {
 }
 
 func mustLoadContract(name string) *contract {
+	return mustLoadContractAt(name, thor.BytesToAddress([]byte(name)))
+}
+
+// mustLoadContractAt loads a builtin contract whose deployed address is fixed
+// (i.e. not derived from its name). Used for contracts that follow an
+// externally specified address such as EIP-2935 HISTORY_STORAGE.
+func mustLoadContractAt(name string, address thor.Address) *contract {
 	asset := "compiled/" + name + ".abi"
 	data := gen.MustABI(asset)
 	abi, err := abi.New(data)
@@ -29,7 +36,7 @@ func mustLoadContract(name string) *contract {
 
 	return &contract{
 		name,
-		thor.BytesToAddress([]byte(name)),
+		address,
 		abi,
 	}
 }

builtin/gen/compiled/History.abi

@@ -0,0 +1 @@
+[{"stateMutability":"nonpayable","type":"fallback"}]

builtin/gen/compiled/History.bin-runtime

@@ -0,0 +1 @@
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

builtin/gen/gen.go

@@ -7,6 +7,6 @@ package gen
 
 //go:generate rm -rf ./compiled/
 //go:generate docker run --rm -v ./:/solidity ghcr.io/argotorg/solc:0.4.24 --optimize-runs 200 --overwrite --bin-runtime --abi -o /solidity/compiled authority.sol energy.sol executor.sol extension.sol extension-v2.sol extension-v3.sol measure.sol params.sol prototype.sol
-//go:generate docker run --rm -v ./:/sources ghcr.io/argotorg/solc:0.8.20 --evm-version paris --optimize --optimize-runs 200 -o /sources/compiled --abi --bin-runtime /sources/staker.sol
+//go:generate docker run --rm -v ./:/sources ghcr.io/argotorg/solc:0.8.20 --evm-version paris --optimize --optimize-runs 200 -o /sources/compiled --abi --bin-runtime /sources/staker.sol /sources/history.sol
 // cleanup - remove all files starting with _
 //go:generate docker run --rm -v ./compiled:/compiled alpine sh -c "find /compiled -type f \\( -name '_*' \\) -delete"

builtin/gen/history.sol

@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: LGPL-3.0
+pragma solidity 0.8.20;
+
+/// @title History serves historical block hashes via the EIP-2935 calling convention.
+///
+/// Calldata is exactly 32 bytes — a uint256 block number with no function
+/// selector. Dispatch therefore goes through the fallback function. All
+/// invalid inputs revert with empty returndata (matching the EIP-2935
+/// reference bytecode's `revert(0, 0)`) so dApps written for ETH mainnet
+/// observe identical failure semantics on Thor.
+contract History {
+    uint256 constant SERVE_WINDOW = 8191;
+
+    // builtin.Extension.Address == thor.BytesToAddress([]byte("Extension"))
+    address constant EXTENSION = 0x0000000000000000000000457874656E73696F6e;
+
+    fallback(bytes calldata input) external returns (bytes memory) {
+        if (input.length != 32) revert();
+        uint256 num = abi.decode(input, (uint256));
+        if (num >= block.number || block.number - num > SERVE_WINDOW) revert();
+
+        bytes32 result = _Extension(EXTENSION).blockID(num);
+
+        assembly {
+            mstore(0, result)
+            return(0, 32)
+        }
+    }
+}
+
+/// @dev Minimal interface against the 0.4.24-compiled Extension builtin
+/// (see builtin/gen/extension.sol). Underscore prefix follows the repo
+/// convention (see _Token, _proto_helper) — the `_*` cleanup step in
+/// gen.go drops the unused artifact from compiled/.
+interface _Extension {
+    function blockID(uint256 num) external view returns (bytes32);
+}

builtin/history_test.go

@@ -0,0 +1,143 @@
+// Copyright (c) 2025 The VeChainThor developers
+
+// Distributed under the GNU Lesser General Public License v3.0 software license, see the accompanying
+// file LICENSE or <https://www.gnu.org/licenses/lgpl-3.0.html>
+
+package builtin_test
+
+import (
+	"encoding/binary"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/vechain/thor/v2/builtin"
+	"github.com/vechain/thor/v2/genesis"
+	"github.com/vechain/thor/v2/test/testchain"
+	"github.com/vechain/thor/v2/tx"
+)
+
+// callHistory invokes the EIP-2935 facade with raw 32-byte calldata
+// (the EIP-2935 convention has no function selector).
+func callHistory(chain *testchain.Chain, num uint32) ([]byte, error) {
+	out, _, err := callHistoryWithGas(chain, num)
+	return out, err
+}
+
+func callHistoryWithGas(chain *testchain.Chain, num uint32) ([]byte, uint64, error) {
+	var data [32]byte
+	binary.BigEndian.PutUint32(data[28:], num)
+	return callHistoryRawWithGas(chain, data[:])
+}
+
+// callHistoryRaw invokes the History contract with the given raw calldata
+// (no selector mangling). Used for testing invalid-length inputs.
+func callHistoryRaw(chain *testchain.Chain, data []byte) ([]byte, error) {
+	out, _, err := callHistoryRawWithGas(chain, data)
+	return out, err
+}
+
+func callHistoryRawWithGas(chain *testchain.Chain, data []byte) ([]byte, uint64, error) {
+	addr := builtin.History.Address
+	clause := tx.NewClause(&addr).WithData(data)
+	trx := new(tx.Builder).
+		ChainTag(chain.Repo().ChainTag()).
+		Expiration(50).
+		Gas(200000).
+		Clause(clause).
+		Build()
+	return chain.ClauseCall(genesis.DevAccounts()[0], trx, 0)
+}
+
+func TestHistory_ForkActivation(t *testing.T) {
+	chain := newChain(t, nil) // SoloFork: INTERSTELLAR = 1
+	require.NoError(t, chain.MintBlock())
+
+	st := chain.State()
+	code, err := st.GetCode(builtin.History.Address)
+	require.NoError(t, err)
+	require.Equal(t, builtin.History.RuntimeBytecodes(), code)
+}
+
+func TestHistory_ValidRead(t *testing.T) {
+	chain := newChain(t, nil)
+	require.NoError(t, chain.MintBlock())
+	require.NoError(t, chain.MintBlock())
+	require.NoError(t, chain.MintBlock())
+
+	want, err := chain.Repo().NewBestChain().GetBlockID(1)
+	require.NoError(t, err)
+
+	got, err := callHistory(chain, 1)
+	require.NoError(t, err)
+	require.Equal(t, want.Bytes(), got)
+}
+
+// TestHistory_WindowBoundary exercises the edges of the [best-8191, best-1]
+// valid range. SERVE_WINDOW is hard-coded to 8191 in history.sol, so the
+// chain must be deep enough to expose both sides of the boundary.
+func TestHistory_WindowBoundary(t *testing.T) {
+	if testing.Short() {
+		t.Skip("requires minting >8191 blocks; skipped in -short mode")
+	}
+	chain := newChain(t, nil)
+	for range 8193 {
+		require.NoError(t, chain.MintBlock())
+	}
+
+	best := chain.Repo().BestBlockSummary().Header.Number()
+
+	// Passing num == block.number must revert per EIP-2935 (execution reverted).
+	got, err := callHistory(chain, best)
+	require.ErrorContains(t, err, "execution reverted")
+	require.Empty(t, got, "EIP-2935 revert must carry no return data")
+
+	// distance == 1: the most recent block, the newest in-window value.
+	newest := best - 1
+	want, err := chain.Repo().NewBestChain().GetBlockID(newest)
+	require.NoError(t, err)
+	got, err = callHistory(chain, newest)
+	require.NoError(t, err)
+	require.Equal(t, want.Bytes(), got)
+
+	// distance == 8191: the oldest in-window value (block.number - num == SERVE_WINDOW).
+	oldestIn := best - 8191
+	want, err = chain.Repo().NewBestChain().GetBlockID(oldestIn)
+	require.NoError(t, err)
+	got, err = callHistory(chain, oldestIn)
+	require.NoError(t, err)
+	require.Equal(t, want.Bytes(), got)
+
+	// distance == 8192: one step past the window — must revert with empty data.
+	out, err := callHistory(chain, oldestIn-1)
+	require.ErrorContains(t, err, "execution reverted")
+	require.Empty(t, out, "EIP-2935 revert must carry no return data")
+}
+
+func TestHistory_FutureBlockReverts(t *testing.T) {
+	chain := newChain(t, nil)
+	require.NoError(t, chain.MintBlock())
+	require.NoError(t, chain.MintBlock())
+
+	best := chain.Repo().BestBlockSummary().Header.Number()
+	out, err := callHistory(chain, best+9999)
+	require.ErrorContains(t, err, "execution reverted")
+	require.Empty(t, out, "EIP-2935 revert must carry no return data")
+}
+
+func TestHistory_InvalidCalldataLength(t *testing.T) {
+	chain := newChain(t, nil)
+	require.NoError(t, chain.MintBlock())
+
+	out, err := callHistoryRaw(chain, make([]byte, 31))
+	require.ErrorContains(t, err, "execution reverted")
+	require.Empty(t, out, "EIP-2935 revert must carry no return data")
+
+	out, err = callHistoryRaw(chain, make([]byte, 33))
+	require.ErrorContains(t, err, "execution reverted")
+	require.Empty(t, out, "EIP-2935 revert must carry no return data")
+
+	out, err = callHistoryRaw(chain, nil)
+	require.ErrorContains(t, err, "execution reverted")
+	require.Empty(t, out, "EIP-2935 revert must carry no return data")
+}

runtime/runtime.go

@@ -161,6 +161,13 @@ func New(
 		}
 	}
 
+	// EIP-2935 HISTORY_STORAGE facade. The contract reads historical block
+	if forkConfig.INTERSTELLAR == ctx.Number {
+		if err := state.SetCode(builtin.History.Address, builtin.History.RuntimeBytecodes()); err != nil {
+			panic(err)
+		}
+	}
+
 	rt := Runtime{
 		chain:       chain,
 		state:       state,