EVMC: Add missing EIP-2929 (Berlin) functions to EVMC host

The update for London (EIP-1559) in 1cdb30df ("bump nim-emvc with evmc revision
8.0.0 to 9.0.0") really bumped EVMC ABI version from 7.5 up to 9.

In other words, it skipped Berlin, going direct from Istanbul to London.

That was accompanied by EVMC changes in 05e9b891 ("EIP-3198: add baseFee op
code in nim-evm"), which added the API changes needed for London.

But the missing Berlin functions weren't added in the move to London.

As a result, our EVMC host became incompatible with Berlin, London, and really
all revisions of the ABI, and if a third party EVM was loaded, it crashed.

This commit adds the missing Berlin host support, and makes our ABI
binary-compatible with real EVMC again.

Signed-off-by: Jamie Lokier <jamie@shareable.org>

nimbus/transaction/evmc_host_glue.nim

@@ -64,6 +64,14 @@ proc emitLog(p: evmc_host_context, address: var evmc_address,
   toHost(p).emitLog(address.fromEvmc, data, data_size,
                     cast[ptr HostTopic](topics), topics_count)
 
+proc accessAccount(p: evmc_host_context,
+                   address: var evmc_address): evmc_access_status {.cdecl.} =
+  toHost(p).accessAccount(address.fromEvmc)
+
+proc accessStorage(p: evmc_host_context, address: var evmc_address,
+                   key: var evmc_bytes32): evmc_access_status {.cdecl.} =
+  toHost(p).accessStorage(address.fromEvmc, key.fromEvmc)
+
 proc evmcGetHostInterface(): ref evmc_host_interface =
   var theHostInterface {.global, threadvar.}: ref evmc_host_interface
   if theHostInterface.isNil:
@@ -80,6 +88,8 @@ proc evmcGetHostInterface(): ref evmc_host_interface =
       get_tx_context: getTxContext,
       get_block_hash: getBlockHash,
       emit_log:       emitLog,
+      access_account: accessAccount,
+      access_storage: accessStorage,
     )
   return theHostInterface
 

nimbus/transaction/host_services.nim

@@ -272,6 +272,23 @@ proc emitLog(host: TransactionHost, address: HostAddress,
   host.computation.logEntries.add(log)
   #host.logEntries.add(log)
 
+proc accessAccount(host: TransactionHost, address: HostAddress): EvmcAccessStatus {.show.} =
+  host.vmState.mutateStateDB:
+    if not db.inAccessList(address):
+      db.accessList(address)
+      return EVMC_ACCESS_COLD
+    else:
+      return EVMC_ACCESS_WARM
+
+proc accessStorage(host: TransactionHost, address: HostAddress,
+                   key: HostKey): EvmcAccessStatus {.show.} =
+  host.vmState.mutateStateDB:
+    if not db.inAccessList(address, key):
+      db.accessList(address, key)
+      return EVMC_ACCESS_COLD
+    else:
+      return EVMC_ACCESS_WARM
+
 when use_evmc_glue:
   {.pop: inline.}
   const included_from_host_services = true

nimbus/transaction/host_types.nim

@@ -46,6 +46,7 @@ type
   EvmcStatusCode*    = evmc_status_code
   EvmcCallKind*      = evmc_call_kind
   EvmcStorageStatus* = evmc_storage_status
+  EvmcAccessStatus*  = evmc_access_status
   EvmcTxContext*     = evmc_tx_context
   EvmcMessage*       = evmc_message
   EvmcResult*        = evmc_result
@@ -95,4 +96,4 @@ template isStatic*(msg: EvmcMessage): bool =
 # `evmc_flags` won't export the flags, `evmc_flag_bit_shifts` must be used.
 export
   evmc_status_code, evmc_call_kind,
-  evmc_flag_bit_shifts, evmc_storage_status
+  evmc_flag_bit_shifts, evmc_storage_status, evmc_access_status

nimbus/vm/evmc_api.nim

@@ -66,6 +66,10 @@ type
     emit_log*: proc(context: evmc_host_context, address: EthAddress,
                     data: ptr byte, data_size: uint,
                     topics: ptr evmc_bytes32, topics_count: uint) {.cdecl, gcsafe.}
+    access_account*: proc(context: evmc_host_context,
+                          address: EthAddress): evmc_access_status {.cdecl, gcsafe.}
+    access_storage*: proc(context: evmc_host_context, address: EthAddress,
+                          key: var evmc_bytes32): evmc_access_status {.cdecl, gcsafe.}
 
 proc nim_host_get_interface*(): ptr nimbus_host_interface {.importc, cdecl.}
 proc nim_host_create_context*(vmstate: pointer, msg: ptr evmc_message): evmc_host_context {.importc, cdecl.}
@@ -139,6 +143,15 @@ proc emitLog*(ctx: HostContext, address: EthAddress, data: openArray[byte],
 proc call*(ctx: HostContext, msg: nimbus_message): nimbus_result {.inline.} =
   ctx.host.call(ctx.context, msg.unsafeAddr)
 
+proc accessAccount*(ctx: HostContext,
+                    address: EthAddress): evmc_access_status {.inline.} =
+  ctx.host.access_account(ctx.context, address)
+
+proc accessStorage*(ctx: HostContext, address: EthAddress,
+                    key: Uint256): evmc_access_status {.inline.} =
+  var key = toEvmc(key)
+  ctx.host.access_storage(ctx.context, address, key)
+
 #proc vmHost*(vmState: BaseVMState, gasPrice: GasInt, origin: EthAddress): HostContext =
 #  let host = nim_host_get_interface()
 #  let context = nim_host_create_context(cast[pointer](vmState), gasPrice, toEvmc(origin))

nimbus/vm/evmc_host.nim

@@ -124,6 +124,24 @@ proc hostEmitLogImpl(ctx: Computation, address: EthAddress,
   log.address = address
   ctx.addLogEntry(log)
 
+proc hostAccessAccountImpl(ctx: Computation, address: EthAddress): evmc_access_status {.cdecl.} =
+  ctx.vmState.mutateStateDB:
+    if not db.inAccessList(address):
+      db.accessList(address)
+      return EVMC_ACCESS_COLD
+    else:
+      return EVMC_ACCESS_WARM
+
+proc hostAccessStorageImpl(ctx: Computation, address: EthAddress,
+                           key: var evmc_bytes32): evmc_access_status {.cdecl.} =
+  let slot = Uint256.fromEvmc(key)
+  ctx.vmState.mutateStateDB:
+    if not db.inAccessList(address, slot):
+      db.accessList(address, slot)
+      return EVMC_ACCESS_COLD
+    else:
+      return EVMC_ACCESS_WARM
+
 proc enterCreateImpl(c: Computation, m: nimbus_message): Computation =
   # TODO: use evmc_message to evoid copy
   let childMsg = Message(
@@ -215,6 +233,8 @@ proc initHostInterface(): evmc_host_interface =
   result.get_tx_context = cast[evmc_get_tx_context_fn](hostGetTxContextImpl)
   result.get_block_hash = cast[evmc_get_block_hash_fn](hostGetBlockHashImpl)
   result.emit_log = cast[evmc_emit_log_fn](hostEmitLogImpl)
+  result.access_account = cast[evmc_access_account_fn](hostAccessAccountImpl)
+  result.access_storage = cast[evmc_access_storage_fn](hostAccessStorageImpl)
 
 proc vmSetOptionImpl(vm: ptr evmc_vm, name, value: cstring): evmc_set_option_result {.cdecl.} =
   return EVMC_SET_OPTION_INVALID_NAME