nimbus-eth1/nimbus/evm/transaction_tracer.nim

130 lines
4.2 KiB
Nim

import
json, strutils, sets, hashes,
chronicles, eth/common, stint,
./types, ./memory, ./stack, ../db/accounts_cache,
eth/trie/hexary, nimcrypto/utils,
./interpreter/op_codes
logScope:
topics = "vm opcode"
proc hash*(x: UInt256): Hash =
result = hash(x.toByteArrayBE)
proc initTracer*(tracer: var TransactionTracer, flags: set[TracerFlags] = {}) =
tracer.trace = newJObject()
# make appear at the top of json object
tracer.trace["gas"] = %0
tracer.trace["failed"] = %false
tracer.trace["returnValue"] = %""
tracer.trace["structLogs"] = newJArray()
tracer.flags = flags
tracer.accounts = initHashSet[EthAddress]()
tracer.storageKeys = @[]
proc prepare*(tracer: var TransactionTracer, compDepth: int) =
# this uncommon arragement is intentional
# compDepth will be varying up and down: 1,2,3,4,3,3,2,2,1
# see issue #245 and PR #247 discussion
if compDepth >= tracer.storageKeys.len:
let prevLen = tracer.storageKeys.len
tracer.storageKeys.setLen(compDepth + 1)
for i in prevLen ..< tracer.storageKeys.len - 1:
tracer.storageKeys[i] = initHashSet[UInt256]()
tracer.storageKeys[compDepth] = initHashSet[UInt256]()
proc rememberStorageKey(tracer: var TransactionTracer, compDepth: int, key: UInt256) =
tracer.storageKeys[compDepth].incl key
iterator storage(tracer: TransactionTracer, compDepth: int): UInt256 =
doAssert compDepth >= 0 and compDepth < tracer.storageKeys.len
for key in tracer.storageKeys[compDepth]:
yield key
proc traceOpCodeStarted*(tracer: var TransactionTracer, c: Computation, op: Op): int =
if unlikely tracer.trace.isNil:
tracer.initTracer()
let j = newJObject()
tracer.trace["structLogs"].add(j)
j["op"] = %(($op).toUpperAscii)
j["pc"] = %(c.code.pc - 1)
j["depth"] = %(c.msg.depth + 1)
j["gas"] = %c.gasMeter.gasRemaining
# log stack
if TracerFlags.DisableStack notin tracer.flags:
let st = newJArray()
for v in c.stack.values:
st.add(%v.dumpHex())
j["stack"] = st
# log memory
if TracerFlags.DisableMemory notin tracer.flags:
let mem = newJArray()
const chunkLen = 32
let numChunks = c.memory.len div chunkLen
for i in 0 ..< numChunks:
mem.add(%c.memory.bytes.toOpenArray(i * chunkLen, (i + 1) * chunkLen - 1).toHex())
j["memory"] = mem
if TracerFlags.EnableAccount in tracer.flags:
case op
of Call, CallCode, DelegateCall, StaticCall:
if c.stack.values.len > 2:
tracer.accounts.incl c.stack[^2, EthAddress]
of ExtCodeCopy, ExtCodeSize, Balance, SelfDestruct:
if c.stack.values.len > 1:
tracer.accounts.incl c.stack[^1, EthAddress]
else:
discard
if TracerFlags.DisableStorage notin tracer.flags:
if op == Sstore:
if c.stack.values.len > 1:
tracer.rememberStorageKey(c.msg.depth, c.stack[^1, UInt256])
result = tracer.trace["structLogs"].len - 1
proc traceOpCodeEnded*(tracer: var TransactionTracer, c: Computation, op: Op, lastIndex: int) =
let j = tracer.trace["structLogs"].elems[lastIndex]
# TODO: figure out how to get storage
# when contract execution interrupted by exception
if TracerFlags.DisableStorage notin tracer.flags:
var storage = newJObject()
if c.msg.depth < tracer.storageKeys.len:
var stateDB = c.vmState.stateDB
for key in tracer.storage(c.msg.depth):
let value = stateDB.getStorage(c.msg.contractAddress, key)
storage[key.dumpHex] = %(value.dumpHex)
j["storage"] = storage
let gasRemaining = j["gas"].getBiggestInt()
j["gasCost"] = %(gasRemaining - c.gasMeter.gasRemaining)
if op in {Return, Revert} and TracerFlags.DisableReturnData notin tracer.flags:
let returnValue = %("0x" & toHex(c.output, true))
j["returnValue"] = returnValue
tracer.trace["returnValue"] = returnValue
trace "Op", json = j.pretty()
proc traceError*(tracer: var TransactionTracer, c: Computation) =
if tracer.trace["structLogs"].elems.len > 0:
let j = tracer.trace["structLogs"].elems[^1]
j["error"] = %(c.error.info)
trace "Error", json = j.pretty()
# even though the gasCost is incorrect,
# we have something to display,
# it is an error anyway
let gasRemaining = j["gas"].getBiggestInt()
j["gasCost"] = %(gasRemaining - c.gasMeter.gasRemaining)
tracer.trace["failed"] = %true