nimbus-eth2/nfuzz/libnfuzz.nim

100 lines
3.1 KiB
Nim

import
endians, stew/ptrops, stew/ranges/ptr_arith,
../beacon_chain/[ssz, state_transition],
../beacon_chain/spec/[datatypes, helpers, digest, validator, beaconstate],
# Required for deserialisation of ValidatorSig in Attestation due to
# https://github.com/nim-lang/Nim/issues/11225
../beacon_chain/spec/crypto
type
BlockInput = object
state: BeaconState
beaconBlock: BeaconBlock
AttestationInput = object
state: BeaconState
attestation: Attestation
# TODO: change ptr uint to ptr csize_t when available in newer Nim version.
proc copyState(state: BeaconState, output: ptr byte,
output_size: ptr uint): bool {.raises:[].} =
var resultState: seq[byte]
try:
resultState = SSZ.encode(state)
except IOError, Defect:
return false
if resultState.len.uint <= output_size[]:
output_size[] = resultState.len.uint
# TODO: improvement might be to write directly to buffer with OutputStream
# and SszWriter
copyMem(output, unsafeAddr resultState[0], output_size[])
result = true
proc nfuzz_block(input: openArray[byte], output: ptr byte,
output_size: ptr uint): bool {.exportc, raises:[].} =
var data: BlockInput
try:
data = SSZ.decode(input, BlockInput)
except MalformedSszError, SszSizeMismatchError, RangeError:
return false
try:
result = state_transition(data.state, data.beaconBlock, flags = {})
except ValueError, RangeError, Exception:
discard
if result:
result = copyState(data.state, output, output_size)
proc nfuzz_attestation(input: openArray[byte], output: ptr byte,
output_size: ptr uint): bool {.exportc, raises:[].} =
var
data: AttestationInput
cache = get_empty_per_epoch_cache()
try:
data = SSZ.decode(input, AttestationInput)
except MalformedSszError, SszSizeMismatchError, RangeError:
return false
try:
result = process_attestation(data.state, data.attestation,
flags = {}, cache)
except ValueError, RangeError:
discard
if result:
result = copyState(data.state, output, output_size)
# 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 output.
# 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, output: var openArray[uint64]): bool
{.exportc, raises:[].} =
var seed: Eth2Digest
# Should be OK as max 2 bytes are passed by the framework.
let list_size = output.len.uint64
copyMem(addr(seed.data), input_seed, sizeof(seed.data))
var shuffled_seq: seq[ValidatorIndex]
try:
shuffled_seq = get_shuffled_seq(seed, list_size)
except RangeError:
return false
# TODO: Hah! AssertionError doesn't get picked up by raises. Do we let them
# slip or shall we wrap one big try/except AssertionError around the calls?
doAssert(list_size == shuffled_seq.len.uint64)
for i in 0..<list_size:
# ValidatorIndex is currently wrongly uint32 so we copy this 1 by 1,
# assumes passed output is zeroed.
copyMem(offset(addr output, i.int), shuffled_seq[i.int].unsafeAddr,
sizeof(ValidatorIndex))
result = true