nim-libp2p-experimental/libp2p/protocols/identify.nim

156 lines
4.7 KiB
Nim

## Nim-LibP2P
## Copyright (c) 2019 Status Research & Development GmbH
## Licensed under either of
## * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE))
## * MIT license ([LICENSE-MIT](LICENSE-MIT))
## at your option.
## This file may not be copied, modified, or distributed except according to
## those terms.
import options
import chronos, chronicles
import ../protobuf/minprotobuf,
../peerinfo,
../stream/connection,
../peerid,
../crypto/crypto,
../multiaddress,
../protocols/protocol,
../utility
logScope:
topics = "identify"
const
IdentifyCodec* = "/ipfs/id/1.0.0"
IdentifyPushCodec* = "/ipfs/id/push/1.0.0"
ProtoVersion* = "ipfs/0.1.0"
AgentVersion* = "nim-libp2p/0.0.1"
#TODO: implement push identify, leaving out for now as it is not essential
type
IdentityNoMatchError* = object of CatchableError
IdentityInvalidMsgError* = object of CatchableError
IdentifyInfo* = object
pubKey*: Option[PublicKey]
addrs*: seq[MultiAddress]
observedAddr*: Option[MultiAddress]
protoVersion*: Option[string]
agentVersion*: Option[string]
protos*: seq[string]
Identify* = ref object of LPProtocol
peerInfo*: PeerInfo
proc encodeMsg*(peerInfo: PeerInfo, observedAddr: Multiaddress): ProtoBuffer =
result = initProtoBuffer()
result.write(1, peerInfo.publicKey.get().getBytes().tryGet())
for ma in peerInfo.addrs:
result.write(2, ma.data.buffer)
for proto in peerInfo.protocols:
result.write(3, proto)
result.write(4, observedAddr.data.buffer)
let protoVersion = ProtoVersion
result.write(5, protoVersion)
let agentVersion = AgentVersion
result.write(6, agentVersion)
result.finish()
proc decodeMsg*(buf: seq[byte]): Option[IdentifyInfo] =
var
iinfo: IdentifyInfo
pubKey: PublicKey
oaddr: MultiAddress
protoVersion: string
agentVersion: string
var pb = initProtoBuffer(buf)
let r1 = pb.getField(1, pubKey)
let r2 = pb.getRepeatedField(2, iinfo.addrs)
let r3 = pb.getRepeatedField(3, iinfo.protos)
let r4 = pb.getField(4, oaddr)
let r5 = pb.getField(5, protoVersion)
let r6 = pb.getField(6, agentVersion)
let res = r1.isOk() and r2.isOk() and r3.isOk() and
r4.isOk() and r5.isOk() and r6.isOk()
if res:
if r1.get():
iinfo.pubKey = some(pubKey)
if r4.get():
iinfo.observedAddr = some(oaddr)
if r5.get():
iinfo.protoVersion = some(protoVersion)
if r6.get():
iinfo.agentVersion = some(agentVersion)
trace "decodeMsg: decoded message", pubkey = ($pubKey).shortLog,
addresses = $iinfo.addrs, protocols = $iinfo.protos,
observable_address = $iinfo.observedAddr,
proto_version = $iinfo.protoVersion,
agent_version = $iinfo.agentVersion
some(iinfo)
else:
trace "decodeMsg: failed to decode received message"
none[IdentifyInfo]()
proc newIdentify*(peerInfo: PeerInfo): Identify =
new result
result.peerInfo = peerInfo
result.init()
method init*(p: Identify) =
proc handle(conn: Connection, proto: string) {.async, gcsafe, closure.} =
try:
defer:
trace "exiting identify handler", oid = conn.oid
await conn.close()
trace "handling identify request", oid = conn.oid
var pb = encodeMsg(p.peerInfo, conn.observedAddr)
await conn.writeLp(pb.buffer)
except CancelledError as exc:
raise exc
except CatchableError as exc:
trace "exception in identify handler", exc = exc.msg
p.handler = handle
p.codec = IdentifyCodec
proc identify*(p: Identify,
conn: Connection,
remotePeerInfo: PeerInfo): Future[IdentifyInfo] {.async, gcsafe.} =
trace "initiating identify", peer = $conn
var message = await conn.readLp(64*1024)
if len(message) == 0:
trace "identify: Empty message received!"
raise newException(IdentityInvalidMsgError, "Empty message received!")
let infoOpt = decodeMsg(message)
if infoOpt.isNone():
raise newException(IdentityInvalidMsgError, "Incorrect message received!")
result = infoOpt.get()
if not isNil(remotePeerInfo) and result.pubKey.isSome:
let peer = PeerID.init(result.pubKey.get())
if peer.isErr:
raise newException(IdentityInvalidMsgError, $peer.error)
else:
# do a string comaprison of the ids,
# because that is the only thing we
# have in most cases
if peer.get() != remotePeerInfo.peerId:
trace "Peer ids don't match",
remote = peer.get().pretty(),
local = remotePeerInfo.id
raise newException(IdentityNoMatchError, "Peer ids don't match")
proc push*(p: Identify, conn: Connection) {.async.} =
await conn.write(IdentifyPushCodec)
var pb = encodeMsg(p.peerInfo, conn.observedAddr)
await conn.writeLp(pb.buffer)