import asyncdispatch, asyncnet, os, strformat, strutils, tables from nativeSockets import Domain, SockType, Protocol from net import IpAddress, Port, isIpAddress, `$` import asyncutils import ../../message import random type PunchdResponse = Future[tuple[msgContent: string, sock: AsyncSocket]] PunchdProgressCb = proc (future: PunchdResponse, msgContent: string) {.async.} OutgoingPunchdMessage = object future: PunchdResponse progressCb: PunchdProgressCb PunchdConnection = object sock: AsyncSocket outMessages: TableRef[string, OutgoingPunchdMessage] inConnections: FutureStream[AsyncSocket] ServerConnection = object sock: AsyncSocket outMessages: TableRef[string, Future[string]] peerNotifications: FutureStream[string] # Punchd messages ProgressTcpSyniConnect* = object command: string args: string # Server messages OkGetInfo* = object ip: string ports: array[3, uint16] NotifyEndpoint* = object command: string ip: IpAddress port: Port NotifyPeer* = object sender: string recipient: string command: string srcIp: IpAddress srcPorts: array[3, Port] dstIp: IpAddress dstPorts: array[3, Port] seqNumbers: seq[uint32] # Exceptions PunchdError = object of ValueError # FIXME: not used yet ServerError = object of ValueError proc usage() = echo &"usage: {paramStr(0)} SERVER_HOSTNAME SERVER_PORT PEER_ID [OTHER_PEER_ID]" proc handleServerMessages(connection: ServerConnection) {.async.} = while true: let line = await connection.sock.recvLine(maxLength = 400) let args = line.parseArgs(3, 1) case args[0]: of "ok": let future = connection.outMessages[args[1]] connection.outMessages.del(args[1]) future.complete(args[2]) of "error": let future = connection.outMessages[args[1]] connection.outMessages.del(args[1]) future.fail(newException(ServerError, args[2])) of "notify-peer": asyncCheck connection.peerNotifications.write(line.substr(args[0].len + 1)) else: raise newException(ValueError, "invalid server message") proc handlePunchdMessages(connection: PunchdConnection) {.async.} = while true: let fd = connection.sock.getFd.AsyncFD let resp = await fd.asyncRecvMsg(size = 400, cmsgSize = sizeof(AsyncFD)) let line = resp.data.strip(leading = false, trailing = true, chars = {'\n'}) let args = line.parseArgs(3, 1) case args[0]: of "ok": let outMsg = connection.outMessages[args[1]] connection.outMessages.del(args[1]) if resp.cmsgs.len != 1: raise newException(ValueError, "invalid punchd message") let sock = newAsyncSocket(resp.cmsgs[0].getFd) register(sock.getFd.AsyncFD) outMsg.future.complete((args[2], sock)) of "error": let outMsg = connection.outMessages[args[1]] connection.outMessages.del(args[1]) outMsg.future.fail(newException(ServerError, args[2])) of "progress": let outMsg = connection.outMessages[args[1]] asyncCheck outMsg.progressCb(outMsg.future, args[2]) else: raise newException(ValueError, "invalid punchd message") proc sendRequest(connection: PunchdConnection, command: string, content: string, progressCb: PunchdProgressCb = nil): PunchdResponse = result = newFuture[PunchdResponse.T]("sendRequest") let id = $rand(uint32) asyncCheck connection.sock.send(&"{command}|{id}|{content}\n") let outMsg = OutgoingPunchdMessage(future: result, progressCb: progressCb) echo "id = ", id connection.outMessages[id] = outMsg proc sendRequest(connection: ServerConnection, command: string, content: string): Future[string] = result = newFuture[string]("sendRequest") let id = $rand(uint32) asyncCheck connection.sock.send(&"{command}|{id}|{content}\n") connection.outMessages[id] = result proc acceptConnection(punchdConn: PunchdConnection, command: string, msgContent: string) {.async.} = echo "accepting connection ", msgContent let resp = await punchdConn.sendRequest(command, msgContent) asyncCheck punchdConn.inConnections.write(resp.sock) proc handlePeerNotifications(serverConn: ServerConnection, punchdConn: PunchdConnection, peerId: string) {.async.} = while true: let (hasData, data) = await serverConn.peerNotifications.read if not hasData: break try: let msg = parseMessage[NotifyPeer](data) # FIXME: check if we want to receive messages from the sender echo "received message from ", msg.sender let srcPorts = msg.srcPorts.join(",") let dstPorts = msg.dstPorts.join(",") let seqNumbers = msg.seqNumbers.join(",") let req = &"{msg.srcIp}|{srcPorts}|{msg.dstIp}|{dstPorts}|{seqNumbers}" asyncCheck acceptConnection(punchdConn, msg.command, req) except ValueError as e: echo e.msg discard proc punchHole(punchdConn: PunchdConnection, serverConn: ServerConnection, ipAddress: IpAddress, peerId: string, otherPeerId: string): Future[AsyncSocket] {.async.} = let sResp = await serverConn.sendRequest("get-info", otherPeerId) let peerInfo = parseMessage[OkGetInfo](sResp) proc progressCb(future: PunchdResponse, msgContent: string) {.async.} = try: let parsedResp = parseMessage[ProgressTcpSyniConnect](msgContent) let req = &"{peerId}|{otherPeerId}|{parsedResp.command}|{parsedResp.args}" discard await serverConn.sendRequest("notify-peer", req) except ServerError as e: future.fail(e) except ValueError as e: future.fail(e) let myPorts = &"{1234},{1234},{1234}" let peerPorts = peerInfo.ports.join(",") let req = &"{ipAddress}|{myPorts}|{peerInfo.ip}|{peerPorts}" let pResp = await punchdConn.sendRequest("tcp-syni-connect", req, progressCb) result = pResp.sock proc runApp(serverHostname: string, serverPort: Port, peerId: string, otherPeerId: string = "") {.async.} = # TODO: determine endpoint in another proc randomize() # initialize random number generator var punchdConn = PunchdConnection() punchdConn.sock = newAsyncSocket(AF_UNIX, SOCK_STREAM, IPPROTO_IP) punchdConn.outMessages = newTable[string, OutgoingPunchdMessage]() punchdConn.inConnections = newFutureStream[AsyncSocket]("runApp") await punchdConn.sock.connectUnix("/tmp/punchd.socket") var serverConn = ServerConnection() serverConn.sock = await asyncnet.dial(serverHostname, serverPort, IPPROTO_TCP) serverConn.outMessages = newTable[string, Future[string]]() serverConn.peerNotifications = newFutureStream[string]("runApp") let resp = await serverConn.sock.recvLine(maxLength = 400) let endpoint = parseMessage[NotifyEndpoint](resp) echo &"rendezvous server says I am {endpoint.ip}:{endpoint.port.int}" asyncCheck handlePunchdMessages(punchdConn) asyncCheck handleServerMessages(serverConn) asyncCheck handlePeerNotifications(serverConn, punchdConn, peerId) if otherPeerId.len == 0: # register and wait for connections let req = &"{peerId}|{endpoint.ip}|{endpoint.port.int},{endpoint.port.int},{endpoint.port.int}" discard await serverConn.sendRequest("register", req) echo "registered" while true: let (hasSock, sock) = await punchdConn.inConnections.read if not hasSock: break echo "got connection" let msg = await sock.recv(1000) echo "received message: ", msg await sock.send("pong") else: # initiate a new connection let sock = await punchHole(punchdConn, serverConn, endpoint.ip, peerId, otherPeerId) await sock.send("ping") let msg = await sock.recv(1000) echo "received message: ", msg proc main() = if paramCount() < 3 or paramCount() > 4: usage() quit(1) let portNumber = paramStr(2).parseUInt if portNumber > uint16.high: usage() quit(1) if paramCount() == 4: waitFor runApp(paramStr(1), Port(portNumber), paramStr(3), paramStr(4)) else: waitFor runApp(paramStr(1), Port(portNumber), paramStr(3)) when isMainModule: main()