nimbus-eth2/nfuzz/libnfuzz.nim

174 lines
6.8 KiB
Nim

# Required for deserialisation of ValidatorSig in Attestation due to
# https://github.com/nim-lang/Nim/issues/11225
import
stew/ptrops, stew/ranges/ptr_arith, chronicles,
../beacon_chain/spec/datatypes/phase0,
../beacon_chain/spec/[
beaconstate, eth2_ssz_serialization, forks, validator, state_transition,
state_transition_block]
type
AttestationInput = object
state: phase0.BeaconState
attestation: Attestation
AttesterSlashingInput = object
state: phase0.BeaconState
attesterSlashing: AttesterSlashing
BlockInput = object
state: phase0.BeaconState
beaconBlock: phase0.SignedBeaconBlock
BlockHeaderInput = BlockInput
DepositInput = object
state: phase0.BeaconState
deposit: Deposit
ProposerSlashingInput = object
state: phase0.BeaconState
proposerSlashing: ProposerSlashing
VoluntaryExitInput = object
state: phase0.BeaconState
exit: SignedVoluntaryExit
# This and AssertionError are raised to indicate programming bugs
# A wrapper to allow exception tracking to identify unexpected exceptions
FuzzCrashError = object of CatchableError
# TODO: change ptr uint to ptr csize_t when available in newer Nim version.
proc copyState(state: phase0.BeaconState, xoutput: ptr byte,
xoutput_size: ptr uint): bool {.raises: [FuzzCrashError, Defect].} =
var resultState =
try:
SSZ.encode(state)
except IOError as e:
# Shouldn't occur as the writer isn't a file
raise newException(FuzzCrashError, "Unexpected failure to serialize.", e)
if unlikely(resultState.len.uint > xoutput_size[]):
let msg = (
"Not enough xoutput buffer provided to nimbus harness. Provided: " &
$(xoutput_size[]) &
"Required: " &
$resultState.len.uint
)
raise newException(FuzzCrashError, msg)
xoutput_size[] = resultState.len.uint
# TODO: improvement might be to write directly to buffer with xoutputStream
# and SszWriter (but then need to ensure length doesn't overflow)
copyMem(xoutput, unsafeAddr resultState[0], xoutput_size[])
result = true
template decodeAndProcess(typ, process: untyped): bool =
let flags {.inject.} = if disable_bls: {skipBlsValidation} else: {}
var
cache {.used, inject.} = StateCache()
data {.inject.} = newClone(
try:
SSZ.decode(input, typ)
except MalformedSszError as e:
raise newException(
FuzzCrashError,
"Malformed SSZ, likely bug in preprocessing.", e)
except SszSizeMismatchError as e:
raise newException(
FuzzCrashError,
"SSZ size mismatch, likely bug in preprocessing.", e)
)
let processOk =
try:
process
except IOError as e:
raise newException(
FuzzCrashError, "Unexpected (logging?) IOError in state transition", e,
)
except ValueError as e:
raise newException(
FuzzCrashError,
"Unexpected (logging?) IOError in state transition", e)
except Exception as e:
# TODO why an Exception?
# Lots of vendor code looks like it might raise a bare exception type
raise newException(FuzzCrashError, "Unexpected Exception in state transition", e)
if processOk:
copyState(data.state, xoutput, xoutput_size)
else:
false
proc nfuzz_attestation(input: openArray[byte], xoutput: ptr byte,
xoutput_size: ptr uint, disable_bls: bool): bool {.exportc, raises: [FuzzCrashError, Defect].} =
decodeAndProcess(AttestationInput):
process_attestation(data.state, data.attestation, flags, 0.Gwei, cache).isOk
proc nfuzz_attester_slashing(input: openArray[byte], xoutput: ptr byte,
xoutput_size: ptr uint, disable_bls: bool): bool {.exportc, raises: [FuzzCrashError, Defect].} =
decodeAndProcess(AttesterSlashingInput):
process_attester_slashing(defaultRuntimeConfig, data.state, data.attesterSlashing, flags, cache).isOk
proc nfuzz_block(input: openArray[byte], xoutput: ptr byte,
xoutput_size: ptr uint, disable_bls: bool): bool {.exportc, raises: [FuzzCrashError, Defect].} =
# There's not a perfect approach here, but it's not worth switching the rest
# and requiring HashedBeaconState (yet). So to keep consistent, puts wrapper
# only in one function.
proc state_transition(
cfg: RuntimeConfig, data: auto, blck: auto, flags: auto,
rollback: RollbackForkedHashedProc): auto =
var
fhState = (ref ForkedHashedBeaconState)(
hbsPhase0: phase0.HashedBeaconState(
data: data.state, root: hash_tree_root(data.state)),
beaconStateFork: forkPhase0)
cache = StateCache()
rewards = RewardInfo()
result =
state_transition(
cfg, fhState[], blck, cache, rewards, flags, rollback)
data.state = fhState.hbsPhase0.data
decodeAndProcess(BlockInput):
state_transition(defaultRuntimeConfig, data, data.beaconBlock, flags, noRollback)
proc nfuzz_block_header(input: openArray[byte], xoutput: ptr byte,
xoutput_size: ptr uint, disable_bls: bool): bool {.exportc, raises: [FuzzCrashError, Defect].} =
decodeAndProcess(BlockHeaderInput):
process_block_header(data.state, data.beaconBlock.message, flags, cache).isOk
proc nfuzz_deposit(input: openArray[byte], xoutput: ptr byte,
xoutput_size: ptr uint, disable_bls: bool): bool {.exportc, raises: [FuzzCrashError, Defect].} =
decodeAndProcess(DepositInput):
process_deposit(defaultRuntimeConfig, data.state, data.deposit, flags).isOk
proc nfuzz_proposer_slashing(input: openArray[byte], xoutput: ptr byte,
xoutput_size: ptr uint, disable_bls: bool): bool {.exportc, raises: [FuzzCrashError, Defect].} =
decodeAndProcess(ProposerSlashingInput):
process_proposer_slashing(defaultRuntimeConfig, data.state, data.proposerSlashing, flags, cache).isOk
proc nfuzz_voluntary_exit(input: openArray[byte], xoutput: ptr byte,
xoutput_size: ptr uint, disable_bls: bool): bool {.exportc, raises: [FuzzCrashError, Defect].} =
decodeAndProcess(VoluntaryExitInput):
process_voluntary_exit(defaultRuntimeConfig, data.state, data.exit, flags, cache).isOk
# Note: Could also accept raw input pointer and access list_size + seed here.
# However, list_size needs to be known also outside this proc to allocate xoutput.
# TODO: rework to copy immediatly in an uint8 openArray, considering we have to
# go over the list anyhow?
proc nfuzz_shuffle(input_seed: ptr byte, xoutput: var openArray[uint64]): bool
{.exportc, raises: [Defect].} =
var seed: Eth2Digest
# Should be OK as max 2 bytes are passed by the framework.
let list_size = xoutput.len
copyMem(addr(seed.data), input_seed, sizeof(seed.data))
var shuffled_seq: seq[ValidatorIndex]
for i in 0..<list_size:
shuffled_seq.add i.ValidatorIndex
shuffle_list(shuffled_seq, seed)
for i in 0..<list_size:
# ValidatorIndex is currently wrongly uint32 so we copy this 1 by 1,
# assumes passed xoutput is zeroed.
copyMem(offset(addr xoutput, i), shuffled_seq[i].unsafeAddr,
sizeof(ValidatorIndex))
true