nim-eth/tests/fuzzing/discovery/fuzz.nim

69 lines
2.2 KiB
Nim

import
streams, posix, sequtils, strutils, chronicles, chronos, stew/byteutils,
eth/p2p/[discovery, kademlia, enode], eth/[keys, rlp],
../../p2p/p2p_test_helper
template fuzz(body) =
# For code we want to fuzz.
try:
body
except:
let e = getCurrentException()
debug "Fuzzer input created exception", exception=e.name, trace=e.repr
discard kill(getpid(), SIGSEGV)
template noFuzz(body) =
# For code not in the scope of the test.
# Lets not have false negatives due to possible issues in this code.
try:
body
except:
let e = getCurrentException()
debug "Exception out of scope of the fuzzing target",
exception=e.name, trace=e.repr
return
const DefaultListeningPort = 30303
proc fuzzTest() =
var
msg: seq[byte]
address: Address
targetNode: DiscoveryProtocol
noFuzz:
# Set up a discovery node, this is the node we target with fuzzing
let
targetNodeKey = initPrivateKey("a2b50376a79b1a8c8a3296485572bdfbf54708bb46d3c25d73d2723aaaf6a617")
targetNodeAddr = localAddress(DefaultListeningPort)
targetNode = newDiscoveryProtocol(targetNodeKey, targetNodeAddr, @[])
# Create the transport as else replies on the messages send will fail.
targetNode.open()
# Read input from stdin (fastest for AFL)
let s = newFileStream(stdin)
# We use binary files as with hex we can get lots of "not hex" failures
var input = s.readAll()
s.close()
# Remove newline if it is there
input.removeSuffix
# TODO: is there a better/faster way?
let payload = input.mapIt(it.byte)
# Sending raw payload is possible but won't find us much. We need a hash and
# a signature, and without it there is a big chance it will always result in
# "Wrong msg mac from" error.
let nodeKey = initPrivateKey("a2b50376a79b1a8c8a3296485572bdfbf54708bb46d3c25d73d2723aaaf6a618")
msg = packData(payload, nodeKey)
address = localAddress(DefaultListeningPort + 1)
try:
targetNode.receive(address, msg)
# These errors are also catched in `processClient` in discovery.nim
# TODO: move them a layer down in discovery so we can do a cleaner test there?
except RlpError, DiscProtocolError:
debug "Receive failed", err = getCurrentExceptionMsg()
fuzz:
fuzzTest()