From abb9e19260bc1fe8fb1df97077a5b52a643d8571 Mon Sep 17 00:00:00 2001 From: Eitan Chatav Date: Fri, 18 Nov 2016 15:47:32 -0800 Subject: [PATCH] integrate proof of work in p2p MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit * check proof of work when connecting to peers * I’m not sure how to get the debug statement on line 418 to work, keep getting syntax errors --- src/node/net/p2p.ml | 64 +++++++++++++++++++++++++++------------------ 1 file changed, 39 insertions(+), 25 deletions(-) diff --git a/src/node/net/p2p.ml b/src/node/net/p2p.ml index 09200f403..75bce8221 100644 --- a/src/node/net/p2p.ml +++ b/src/node/net/p2p.ml @@ -135,7 +135,8 @@ module Make (P: PARAMS) = struct port : int option ; versions : version list ; public_key : Crypto_box.public_key ; - nonce : Crypto_box.nonce ; + proof_of_work : Crypto_box.nonce ; + message_nonce : Crypto_box.nonce ; } | Disconnect | Bootstrap @@ -146,20 +147,21 @@ module Make (P: PARAMS) = struct let open Data_encoding in union ~tag_size:`Uint16 ([ case ~tag:0x00 - (obj5 + (obj6 (req "gid" (Fixed.string gid_length)) (req "port" uint16) (req "pubKey" Crypto_box.public_key_encoding) - (req "nonce" Crypto_box.nonce_encoding) + (req "proof_of_work" Crypto_box.nonce_encoding) + (req "message_nonce" Crypto_box.nonce_encoding) (req "versions" (Variable.list version_encoding))) (function - | Connect { gid ; port ; versions ; public_key ; nonce } -> + | Connect { gid ; port ; versions ; public_key ; proof_of_work; message_nonce } -> let port = match port with None -> 0 | Some port -> port in - Some (gid, port, public_key, nonce, versions) + Some (gid, port, public_key, proof_of_work, message_nonce, versions) | _ -> None) - (fun (gid, port, public_key, nonce, versions) -> + (fun (gid, port, public_key, proof_of_work, message_nonce, versions) -> let port = if port = 0 then None else Some port in - Connect { gid ; port ; versions ; public_key ; nonce }); + Connect { gid ; port ; versions ; public_key ; proof_of_work; message_nonce }); case ~tag:0x01 null (function Disconnect -> Some () | _ -> None) (fun () -> Disconnect); @@ -384,7 +386,7 @@ module Make (P: PARAMS) = struct (including the one sent when the connection is alive). Returns a canceler. *) let connect_to_peer - config limits my_gid my_public_key my_secret_key + config limits my_gid my_public_key my_secret_key my_proof_of_work socket (addr, port) push white_listed = (* a non exception-based cancelation mechanism *) let cancelation, cancel, on_cancel = canceler () in @@ -400,15 +402,24 @@ module Make (P: PARAMS) = struct send_msg socket buf (Connect { gid = my_gid ; public_key = my_public_key ; - nonce = local_nonce ; + proof_of_work = my_proof_of_work ; + message_nonce = local_nonce ; port = config.incoming_port ; versions = P.supported_versions }) >>= fun _ -> pick [ (LU.sleep limits.peer_answer_timeout >>= fun () -> return Disconnect) ; recv_msg socket buf ] >>= function - | Connect { gid; port = listening_port; versions ; public_key ; nonce } -> + | Connect { gid; port = listening_port; versions ; public_key ; proof_of_work ; message_nonce } -> debug "(%a) connection requested from %a @@ %a:%d" pp_gid my_gid pp_gid gid Ipaddr.pp_hum addr port ; - begin match common_version P.supported_versions versions with + let work_proved = + Crypto_box.check_proof_of_work + public_key proof_of_work Crypto_box.default_target in + if not work_proved then + (*debug "connection rejected (invalid proof of work)" + pp_gid my_gid Ipaddr.pp_hum addr port ;*) + cancel () + else + begin match common_version P.supported_versions versions with | None -> debug "(%a) connection rejected (incompatible versions) from %a:%d" pp_gid my_gid Ipaddr.pp_hum addr port ; @@ -417,7 +428,7 @@ module Make (P: PARAMS) = struct if config.closed_network then match listening_port with | Some port when white_listed (addr, port) -> - connected buf local_nonce version gid public_key nonce listening_port + connected buf local_nonce version gid public_key message_nonce listening_port | Some port -> debug "(%a) connection rejected (out of the closed network) from %a:%d" pp_gid my_gid Ipaddr.pp_hum addr port ; @@ -427,8 +438,8 @@ module Make (P: PARAMS) = struct pp_gid my_gid Ipaddr.pp_hum addr ; cancel () else - connected buf local_nonce version gid public_key nonce listening_port - end + connected buf local_nonce version gid public_key message_nonce listening_port + end | Advertise peers -> (* alternatively, one can refuse a connection but reply with some peers, so we accept this info *) @@ -526,10 +537,11 @@ module Make (P: PARAMS) = struct let peers_file_encoding = let open Data_encoding in - obj4 + obj5 (req "gid" string) (req "public_key" Crypto_box.public_key_encoding) (req "secret_key" Crypto_box.secret_key_encoding) + (req "proof_of_work" Crypto_box.nonce_encoding) (req "peers" (obj3 (req "known" @@ -699,12 +711,14 @@ module Make (P: PARAMS) = struct on_cancel (fun () -> close_msg_queue () ; return ()) ; (* fill the known peers pools from last time *) Data_encoding.Json.read_file config.peers_file >>= fun res -> - let known_peers, black_list, my_gid, my_public_key, my_secret_key = + let known_peers, black_list, my_gid, my_public_key, my_secret_key, my_proof_of_work = let init_peers () = let my_gid = fresh_gid () in let (my_secret_key, my_public_key) = Crypto_box.random_keypair () in + let my_proof_of_work = + Crypto_box.generate_proof_of_work my_public_key Crypto_box.default_target in let known_peers = let source = { unreachable_since = None ; connections = None ; @@ -717,23 +731,23 @@ module Make (P: PARAMS) = struct PeerMap.empty config.known_peers in let black_list = BlackList.empty in - known_peers, black_list, my_gid, my_public_key, my_secret_key in + known_peers, black_list, my_gid, my_public_key, my_secret_key, my_proof_of_work in match res with | None -> let known_peers, black_list, my_gid, - my_public_key, my_secret_key = init_peers () in + my_public_key, my_secret_key, my_proof_of_work = init_peers () in debug "(%a) peer cache initiated" pp_gid my_gid ; ref known_peers, ref black_list, my_gid, - my_public_key, my_secret_key + my_public_key, my_secret_key, my_proof_of_work | Some json -> match Data_encoding.Json.destruct peers_file_encoding json with | exception _ -> let known_peers, black_list, my_gid, - my_public_key, my_secret_key = init_peers () in + my_public_key, my_secret_key, my_proof_of_work = init_peers () in debug "(%a) peer cache reset" pp_gid my_gid ; ref known_peers, ref black_list, - my_gid, my_public_key, my_secret_key - | (my_gid, my_public_key, my_secret_key, (k, b, w)) -> + my_gid, my_public_key, my_secret_key, my_proof_of_work + | (my_gid, my_public_key, my_secret_key, my_proof_of_work, (k, b, w)) -> let white_list = List.fold_right PointSet.add w PointSet.empty in let known_peers = @@ -761,7 +775,7 @@ module Make (P: PARAMS) = struct BlackList.empty b in debug "(%a) peer cache loaded" pp_gid my_gid ; ref known_peers, ref black_list, - my_gid, my_public_key, my_secret_key + my_gid, my_public_key, my_secret_key, my_proof_of_work in (* some peer reachability predicates *) let black_listed (addr, _) = @@ -781,6 +795,7 @@ module Make (P: PARAMS) = struct (my_gid, my_public_key, my_secret_key, + my_proof_of_work, PeerMap.fold (fun (addr, port) gid source (k, b, w) -> let infos = match gid, source.connections with @@ -1047,7 +1062,7 @@ module Make (P: PARAMS) = struct else let canceler = connect_to_peer - config limits my_gid my_public_key my_secret_key + config limits my_gid my_public_key my_secret_key my_proof_of_work socket (addr, port) enqueue_event white_listed in debug "(%a) incoming peer @@ %a:%d" pp_gid my_gid Ipaddr.pp_hum addr port ; @@ -1272,4 +1287,3 @@ module Make (P: PARAMS) = struct let get_metadata net gid = net.get_metadata gid let set_metadata net gid meta = net.set_metadata gid meta end -