creates instance of codex dht

codexcrawler/application.nim

@@ -12,6 +12,8 @@ import ./config
 import ./logging
 import ./metrics
 import ./list
+import ./dht
+import ./keyutils
 
 declareGauge(todoNodesGauge, "DHT nodes to be visited")
 declareGauge(okNodesGauge, "DHT nodes successfully contacted")
@@ -29,15 +31,21 @@ type
     todoList*: List
     okNodes*: List
     nokNodes*: List
+    dht*: Dht
 
-proc createDatastore(app: Application): ?!TypedDatastore =
-  without store =? LevelDbDatastore.new(app.config.dataDir), err:
+proc createDatastore(app: Application, path: string): ?!Datastore =
+  without store =? LevelDbDatastore.new(path), err:
     error "Failed to create datastore"
     return failure(err)
+  return success(Datastore(store))
+
+proc createTypedDatastore(app: Application, path: string): ?!TypedDatastore =
+  without store =? app.createDatastore(path), err:
+    return failure(err)
   return success(TypedDatastore.init(store))
 
 proc initializeLists(app: Application): Future[?!void] {.async.} =
-  without store =? app.createDatastore(), err:
+  without store =? app.createTypedDatastore(app.config.dataDir), err:
     return failure(err)
 
   # We can't extract this into a function because gauges cannot be passed as argument.
@@ -64,10 +72,33 @@ proc initializeLists(app: Application): Future[?!void] {.async.} =
 
   return success()
 
+proc initializeDht(app: Application): ?!void =
+  without dhtStore =? app.createDatastore("dht"), err:
+    return failure(err)
+  let keyPath = app.config.dataDir / "privatekey"
+  without privateKey =? setupKey(keyPath), err:
+    return failure(err)
+
+  let announceAddresses = newSeq[MultiAddress]()
+
+  app.dht = Dht.new(
+    privateKey,
+    bindPort = app.config.discPort,
+    announceAddrs = announceAddresses,
+    bootstrapNodes = app.config.bootNodes,
+    store = dhtStore
+  )
+  return success()
+
 proc initializeApp(app: Application): Future[?!void] {.async.} =
   if err =? (await app.initializeLists()).errorOption:
     error "Failed to initialize lists", err = err.msg
     return failure(err)
+
+  if err =? app.initializeDht().errorOption:
+    error "Failed to initialize DHT", err = err.msg
+    return failure(err)
+
   return success()
 
 proc stop*(app: Application) =

codexcrawler/config.nim

@@ -1,4 +1,8 @@
 import std/net
+import std/sequtils
+import pkg/chronicles
+import pkg/libp2p
+import pkg/codexdht
 import ./version
 
 let doc =
@@ -26,13 +30,13 @@ type CrawlerConfig* = ref object
   metricsPort*: Port
   dataDir*: string
   discPort*: Port
-  bootNodes*: seq[string]
+  bootNodes*: seq[SignedPeerRecord]
 
 proc `$`*(config: CrawlerConfig): string =
   "CrawlerConfig:" & " logLevel=" & config.logLevel & " metricsAddress=" &
     $config.metricsAddress & " metricsPort=" & $config.metricsPort & " dataDir=" &
     config.dataDir & " discPort=" & $config.discPort & " bootNodes=" &
-    config.bootNodes.join(";")
+    config.bootNodes.mapIt($it).join(";")
 
 proc getDefaultTestnetBootNodes(): seq[string] =
   @[
@@ -45,11 +49,28 @@ proc getDefaultTestnetBootNodes(): seq[string] =
     "spr:CiUIAhIhAntGLadpfuBCD9XXfiN_43-V3L5VWgFCXxg4a8uhDdnYEgIDARo8CicAJQgCEiECe0Ytp2l-4EIP1dd-I3_jf5XcvlVaAUJfGDhry6EN2dgQsIufsAYaCwoJBNEmoCiRAnV2KkYwRAIgXO3bzd5VF8jLZG8r7dcLJ_FnQBYp1BcxrOvovEa40acCIDhQ14eJRoPwJ6GKgqOkXdaFAsoszl-HIRzYcXKeb7D9",
   ]
 
-proc getBootNodes(input: string): seq[string] =
+proc getBootNodeStrings(input: string): seq[string] =
   if input == "testnet_sprs":
     return getDefaultTestnetBootNodes()
   return input.split(";")
 
+proc stringToSpr(uri: string): SignedPeerRecord = 
+  var res: SignedPeerRecord
+  try:
+    if not res.fromURI(uri):
+      warn "Invalid SignedPeerRecord uri", uri = uri
+      quit QuitFailure
+  except LPError as exc:
+    warn "Invalid SignedPeerRecord uri", uri = uri, error = exc.msg
+    quit QuitFailure
+  except CatchableError as exc:
+    warn "Invalid SignedPeerRecord uri", uri = uri, error = exc.msg
+    quit QuitFailure
+  res
+
+proc getBootNodes(input: string): seq[SignedPeerRecord] =
+  getBootNodeStrings(input).mapIt(stringToSpr(it))
+
 proc parseConfig*(): CrawlerConfig =
   let args = docopt(doc, version = crawlerFullVersion)
 

codexcrawler/dht.nim

@@ -0,0 +1,114 @@
+import std/net
+import pkg/chronicles
+import pkg/chronos
+import pkg/libp2p
+import pkg/questionable
+import pkg/questionable/results
+import pkg/codexdht/discv5/[routing_table, protocol as discv5]
+from pkg/nimcrypto import keccak256
+
+import ./rng
+
+export discv5
+
+logScope:
+  topics = "dht"
+
+type Dht* = ref object
+  protocol*: discv5.Protocol
+  key: PrivateKey
+  peerId: PeerId
+  announceAddrs*: seq[MultiAddress]
+  providerRecord*: ?SignedPeerRecord
+  dhtRecord*: ?SignedPeerRecord
+
+# proc toNodeId*(cid: Cid): NodeId =
+#   ## Cid to discovery id
+#   ##
+
+#   readUintBE[256](keccak256.digest(cid.data.buffer).data)
+
+# proc toNodeId*(host: ca.Address): NodeId =
+#   ## Eth address to discovery id
+#   ##
+
+#   readUintBE[256](keccak256.digest(host.toArray).data)
+
+proc findPeer*(d: Dht, peerId: PeerId): Future[?PeerRecord] {.async.} =
+  trace "protocol.resolve..."
+  ## Find peer using the given Discovery object
+  ##
+  let node = await d.protocol.resolve(toNodeId(peerId))
+
+  return
+    if node.isSome():
+      node.get().record.data.some
+    else:
+      PeerRecord.none
+
+method removeProvider*(d: Dht, peerId: PeerId): Future[void] {.base, gcsafe.} =
+  trace "Removing provider", peerId
+  d.protocol.removeProvidersLocal(peerId)
+
+proc updateAnnounceRecord*(d: Dht, addrs: openArray[MultiAddress]) =
+  d.announceAddrs = @addrs
+
+  trace "Updating announce record", addrs = d.announceAddrs
+  d.providerRecord = SignedPeerRecord
+    .init(d.key, PeerRecord.init(d.peerId, d.announceAddrs))
+    .expect("Should construct signed record").some
+
+  if not d.protocol.isNil:
+    d.protocol.updateRecord(d.providerRecord).expect("Should update SPR")
+
+proc updateDhtRecord*(d: Dht, addrs: openArray[MultiAddress]) =
+  trace "Updating Dht record", addrs = addrs
+  d.dhtRecord = SignedPeerRecord
+    .init(d.key, PeerRecord.init(d.peerId, @addrs))
+    .expect("Should construct signed record").some
+
+  if not d.protocol.isNil:
+    d.protocol.updateRecord(d.dhtRecord).expect("Should update SPR")
+
+proc start*(d: Dht) {.async.} =
+  d.protocol.open()
+  await d.protocol.start()
+
+proc stop*(d: Dht) {.async.} =
+  await d.protocol.closeWait()
+
+proc new*(
+    T: type Dht,
+    key: PrivateKey,
+    bindIp = IPv4_any(),
+    bindPort = 0.Port,
+    announceAddrs: openArray[MultiAddress],
+    bootstrapNodes: openArray[SignedPeerRecord] = [],
+    store: Datastore = SQLiteDatastore.new(Memory).expect("Should not fail!"),
+): Dht =
+  var self =
+    Dht(key: key, peerId: PeerId.init(key).expect("Should construct PeerId"))
+
+  self.updateAnnounceRecord(announceAddrs)
+
+  # --------------------------------------------------------------------------
+  # FIXME disable IP limits temporarily so we can run our workshop. Re-enable
+  #   and figure out proper solution.
+  let discoveryConfig = DiscoveryConfig(
+    tableIpLimits: TableIpLimits(tableIpLimit: high(uint), bucketIpLimit: high(uint)),
+    bitsPerHop: DefaultBitsPerHop,
+  )
+  # --------------------------------------------------------------------------
+
+  self.protocol = newProtocol(
+    key,
+    bindIp = bindIp,
+    bindPort = bindPort,
+    record = self.providerRecord.get,
+    bootstrapRecords = bootstrapNodes,
+    rng = Rng.instance(),
+    providers = ProvidersManager.new(store),
+    config = discoveryConfig,
+  )
+
+  self

codexcrawler/keyutils.nim

@@ -0,0 +1,68 @@
+import pkg/chronicles
+import pkg/questionable/results
+import pkg/libp2p/crypto/crypto
+import pkg/stew/io2
+
+# This file is copied from nim-codex `codex/utils/keyutils.nim`
+
+import ./rng
+
+# from errors.nim:
+template mapFailure*[T, V, E](
+    exp: Result[T, V], exc: typedesc[E]
+): Result[T, ref CatchableError] =
+  ## Convert `Result[T, E]` to `Result[E, ref CatchableError]`
+  ##
+
+  exp.mapErr(
+    proc(e: V): ref CatchableError =
+      (ref exc)(msg: $e)
+  )
+
+# from fileutils.nim
+when defined(windows):
+  import stew/[windows/acl]
+
+proc secureWriteFile*[T: byte | char](
+    path: string, data: openArray[T]
+): IoResult[void] =
+  when defined(windows):
+    let sres = createFilesUserOnlySecurityDescriptor()
+    if sres.isErr():
+      error "Could not allocate security descriptor",
+        path = path, errorMsg = ioErrorMsg(sres.error), errorCode = $sres.error
+      err(sres.error)
+    else:
+      var sd = sres.get()
+      writeFile(path, data, 0o600, secDescriptor = sd.getDescriptor())
+  else:
+    writeFile(path, data, 0o600)
+
+proc checkSecureFile*(path: string): IoResult[bool] =
+  when defined(windows):
+    checkCurrentUserOnlyACL(path)
+  else:
+    ok (?getPermissionsSet(path) == {UserRead, UserWrite})
+
+type
+  KeyError* = object of CatchableError
+
+proc setupKey*(path: string): ?!PrivateKey =
+  if not path.fileAccessible({AccessFlags.Find}):
+    info "Creating a private key and saving it"
+    let
+      res = ?PrivateKey.random(Rng.instance()[]).mapFailure(KeyError)
+      bytes = ?res.getBytes().mapFailure(KeyError)
+
+    ?path.secureWriteFile(bytes).mapFailure(KeyError)
+    return PrivateKey.init(bytes).mapFailure(KeyError)
+
+  info "Found a network private key"
+  if not ?checkSecureFile(path).mapFailure(KeyError):
+    warn "The network private key file is not safe, aborting"
+    return failure newException(
+      KeyError, "The network private key file is not safe"
+    )
+
+  let kb = ?path.readAllBytes().mapFailure(KeyError)
+  return PrivateKey.init(kb).mapFailure(KeyError)

codexcrawler/rng.nim

@@ -0,0 +1,49 @@
+import pkg/libp2p/crypto/crypto
+import pkg/bearssl/rand
+
+# This file is copied from nim-codex `codex/rng.nim`
+
+type
+  RngSampleError = object of CatchableError
+  Rng* = ref HmacDrbgContext
+
+var rng {.threadvar.}: Rng
+
+proc instance*(t: type Rng): Rng =
+  if rng.isNil:
+    rng = newRng()
+  rng
+
+# Random helpers: similar as in stdlib, but with HmacDrbgContext rng
+# TODO: Move these somewhere else?
+const randMax = 18_446_744_073_709_551_615'u64
+
+proc rand*(rng: Rng, max: Natural): int =
+  if max == 0:
+    return 0
+
+  while true:
+    let x = rng[].generate(uint64)
+    if x < randMax - (randMax mod (uint64(max) + 1'u64)): # against modulo bias
+      return int(x mod (uint64(max) + 1'u64))
+
+proc sample*[T](rng: Rng, a: openArray[T]): T =
+  result = a[rng.rand(a.high)]
+
+proc sample*[T](
+    rng: Rng, sample, exclude: openArray[T]
+): T {.raises: [Defect, RngSampleError].} =
+  if sample == exclude:
+    raise newException(RngSampleError, "Sample and exclude arrays are the same!")
+
+  while true:
+    result = rng.sample(sample)
+    if exclude.find(result) != -1:
+      continue
+
+    break
+
+proc shuffle*[T](rng: Rng, a: var openArray[T]) =
+  for i in countdown(a.high, 1):
+    let j = rng.rand(i)
+    swap(a[i], a[j])

config.nims

@@ -2,3 +2,6 @@
   metrics
 # switch("define", "chronicles_runtime_filtering=true")
 switch("define", "chronicles_log_level=TRACE")
+
+when (NimMajor, NimMinor) >= (2, 0):
+  --mm:refc