nim-eth/eth/p2p/discoveryv5/node.nim

142 lines
3.9 KiB
Nim

# nim-eth - Node Discovery Protocol v5
# Copyright (c) 2020-2021 Status Research & Development GmbH
# Licensed and distributed under either of
# * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT).
# * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
# at your option. This file may not be copied, modified, or distributed except according to those terms.
{.push raises: [Defect].}
import
std/hashes,
nimcrypto, stint, chronos, stew/shims/net, chronicles,
../../keys, ../../net/utils,
./enr
export stint
type
NodeId* = UInt256
Address* = object
ip*: ValidIpAddress
port*: Port
Node* = ref object
id*: NodeId
pubkey*: PublicKey
address*: Option[Address]
record*: Record
seen*: bool ## Indicates if there was at least one successful
## request-response with this node.
func toNodeId*(pk: PublicKey): NodeId =
## Convert public key to a node identifier.
# Keccak256 hash is used as defined in ENR spec for scheme v4:
# https://github.com/ethereum/devp2p/blob/master/enr.md#v4-identity-scheme
readUintBE[256](keccak256.digest(pk.toRaw()).data)
func newNode*(r: Record): Result[Node, cstring] =
## Create a new `Node` from a `Record`.
# TODO: Handle IPv6
let pk = r.get(PublicKey)
# This check is redundant for a properly created record as the deserialization
# of a record will fail at `verifySignature` if there is no public key.
if pk.isNone():
return err("Could not recover public key from ENR")
# Also this can not fail for a properly created record as id is checked upon
# deserialization.
let tr = ? r.toTypedRecord()
if tr.ip.isSome() and tr.udp.isSome():
let a = Address(ip: ipv4(tr.ip.get()), port: Port(tr.udp.get()))
ok(Node(id: pk.get().toNodeId(), pubkey: pk.get() , record: r,
address: some(a)))
else:
ok(Node(id: pk.get().toNodeId(), pubkey: pk.get(), record: r,
address: none(Address)))
func update*(n: Node, pk: PrivateKey, ip: Option[ValidIpAddress],
tcpPort, udpPort: Option[Port] = none[Port](),
extraFields: openArray[FieldPair] = []): Result[void, cstring] =
? n.record.update(pk, ip, tcpPort, udpPort, extraFields)
if ip.isSome():
if udpPort.isSome():
let a = Address(ip: ip.get(), port: udpPort.get())
n.address = some(a)
elif n.address.isSome():
let a = Address(ip: ip.get(), port: n.address.get().port)
n.address = some(a)
else:
n.address = none(Address)
else:
n.address = none(Address)
ok()
func hash*(n: Node): hashes.Hash = hash(n.pubkey.toRaw)
func `==`*(a, b: Node): bool =
(a.isNil and b.isNil) or
(not a.isNil and not b.isNil and a.pubkey == b.pubkey)
func hash*(id: NodeId): Hash =
hash(id.toByteArrayBE)
proc random*(T: type NodeId, rng: var BrHmacDrbgContext): T =
var id: NodeId
brHmacDrbgGenerate(addr rng, addr id, csize_t(sizeof(id)))
id
func `$`*(id: NodeId): string =
id.toHex()
func shortLog*(id: NodeId): string =
## Returns compact string representation of ``id``.
var sid = $id
if len(sid) <= 10:
result = sid
else:
result = newStringOfCap(10)
for i in 0..<2:
result.add(sid[i])
result.add("*")
for i in (len(sid) - 6)..sid.high:
result.add(sid[i])
chronicles.formatIt(NodeId): shortLog(it)
func hash*(a: Address): hashes.Hash =
let res = a.ip.hash !& a.port.hash
!$res
func `$`*(a: Address): string =
result.add($a.ip)
result.add(":" & $a.port)
func shortLog*(n: Node): string =
if n.isNil:
"uninitialized"
elif n.address.isNone():
shortLog(n.id) & ":unaddressable"
else:
shortLog(n.id) & ":" & $n.address.get()
chronicles.formatIt(Node): shortLog(it)
func shortLog*(nodes: seq[Node]): string =
result = "["
var first = true
for n in nodes:
if first:
first = false
else:
result.add(", ")
result.add(shortLog(n))
result.add("]")
chronicles.formatIt(seq[Node]): shortLog(it)