ligo/src/lib_shell/peer_validator.ml

410 lines
14 KiB
OCaml

(**************************************************************************)
(* *)
(* Copyright (c) 2014 - 2018. *)
(* Dynamic Ledger Solutions, Inc. <contact@tezos.com> *)
(* *)
(* All rights reserved. No warranty, explicit or implicit, provided. *)
(* *)
(**************************************************************************)
(* FIXME ignore/postpone fetching/validating of block in the future... *)
open Peer_validator_worker_state
module Name = struct
type t = Chain_id.t * P2p_peer.Id.t
let encoding =
Data_encoding.tup2 Chain_id.encoding P2p_peer.Id.encoding
let base = [ "validator.peer" ]
let pp ppf (chain, peer) =
Format.fprintf ppf "%a:%a"
Chain_id.pp_short chain P2p_peer.Id.pp_short peer
end
module Request = struct
include Request
type _ t =
| New_head : Block_hash.t * Block_header.t -> unit t
| New_branch : Block_hash.t * Block_locator.t * Block_locator.seed -> unit t
let view (type a) (req : a t) : view = match req with
| New_head (hash, _) ->
New_head hash
| New_branch (hash, locator, seed) ->
(* the seed is associated to each locator
w.r.t. the peer_id of the sender *)
New_branch (hash, Block_locator.estimated_length seed locator)
end
type limits = {
new_head_request_timeout: float ;
block_header_timeout: float ;
block_operations_timeout: float ;
protocol_timeout: float ;
worker_limits: Worker_types.limits
}
module Types = struct
include Worker_state
type parameters = {
chain_db: Distributed_db.chain_db ;
block_validator: Block_validator.t ;
(* callback to chain_validator *)
notify_new_block: State.Block.t -> unit ;
notify_bootstrapped: unit -> unit ;
notify_termination: unit -> unit ;
limits: limits;
}
type state = {
peer_id: P2p_peer.Id.t ;
parameters : parameters ;
mutable bootstrapped: bool ;
mutable last_validated_head: Block_header.t ;
mutable last_advertised_head: Block_header.t ;
}
let view (state : state) _ : view =
let { bootstrapped ; last_validated_head ; last_advertised_head } = state in
{ bootstrapped ;
last_validated_head = Block_header.hash last_validated_head ;
last_advertised_head = Block_header.hash last_advertised_head }
end
module Worker = Worker.Make (Name) (Event) (Request) (Types)
open Types
type t = Worker.dropbox Worker.t
let debug w =
Format.kasprintf (fun msg -> Worker.record_event w (Debug msg))
let set_bootstrapped pv =
if not pv.bootstrapped then begin
pv.bootstrapped <- true ;
pv.parameters.notify_bootstrapped () ;
end
let bootstrap_new_branch w _ancestor _head unknown_prefix =
let pv = Worker.state w in
let sender_id = Distributed_db.my_peer_id pv.parameters.chain_db in
(* sender and receiver are inverted here because they are from
the point of view of the node sending the locator *)
let seed = {Block_locator.sender_id=pv.peer_id; receiver_id = sender_id } in
let len = Block_locator.estimated_length seed unknown_prefix in
debug w
"validating new branch from peer %a (approx. %d blocks)"
P2p_peer.Id.pp_short pv.peer_id len ;
let pipeline =
Bootstrap_pipeline.create
~notify_new_block:pv.parameters.notify_new_block
~block_header_timeout:pv.parameters.limits.block_header_timeout
~block_operations_timeout:pv.parameters.limits.block_operations_timeout
pv.parameters.block_validator
pv.peer_id pv.parameters.chain_db unknown_prefix in
Worker.protect w
~on_error:begin fun error ->
(* if the peer_validator is killed, let's cancel the pipeline *)
Bootstrap_pipeline.cancel pipeline >>= fun () ->
Lwt.return_error error
end
begin fun () ->
Bootstrap_pipeline.wait pipeline
end >>=? fun () ->
set_bootstrapped pv ;
debug w
"done validating new branch from peer %a."
P2p_peer.Id.pp_short pv.peer_id ;
return ()
let validate_new_head w hash (header : Block_header.t) =
let pv = Worker.state w in
debug w
"fetching operations for new head %a from peer %a"
Block_hash.pp_short hash
P2p_peer.Id.pp_short pv.peer_id ;
map_p
(fun i ->
Worker.protect w begin fun () ->
Distributed_db.Operations.fetch
~timeout:pv.parameters.limits.block_operations_timeout
pv.parameters.chain_db ~peer:pv.peer_id
(hash, i) header.shell.operations_hash
end)
(0 -- (header.shell.validation_passes - 1)) >>=? fun operations ->
debug w
"requesting validation for new head %a from peer %a"
Block_hash.pp_short hash
P2p_peer.Id.pp_short pv.peer_id ;
Block_validator.validate
~notify_new_block:pv.parameters.notify_new_block
pv.parameters.block_validator pv.parameters.chain_db
hash header operations >>=? fun _block ->
debug w
"end of validation for new head %a from peer %a"
Block_hash.pp_short hash
P2p_peer.Id.pp_short pv.peer_id ;
set_bootstrapped pv ;
return ()
let only_if_fitness_increases w distant_header cont =
let pv = Worker.state w in
let chain_state = Distributed_db.chain_state pv.parameters.chain_db in
Chain.head chain_state >>= fun local_header ->
if Fitness.compare
distant_header.Block_header.shell.fitness
(State.Block.fitness local_header) <= 0 then begin
set_bootstrapped pv ;
debug w
"ignoring head %a with non increasing fitness from peer: %a."
Block_hash.pp_short (Block_header.hash distant_header)
P2p_peer.Id.pp_short pv.peer_id ;
(* Don't download a branch that cannot beat the current head. *)
return ()
end else cont ()
let assert_acceptable_head w hash (header: Block_header.t) =
let pv = Worker.state w in
let chain_state = Distributed_db.chain_state pv.parameters.chain_db in
State.Chain.acceptable_block chain_state hash header >>= fun acceptable ->
fail_unless acceptable
(Validation_errors.Checkpoint_error (hash, Some pv.peer_id))
let may_validate_new_head w hash (header : Block_header.t) =
let pv = Worker.state w in
let chain_state = Distributed_db.chain_state pv.parameters.chain_db in
State.Block.known_valid chain_state hash >>= fun valid_block ->
State.Block.known_invalid chain_state hash >>= fun invalid_block ->
State.Block.known_valid chain_state
header.shell.predecessor >>= fun valid_predecessor ->
State.Block.known_invalid chain_state
header.shell.predecessor >>= fun invalid_predecessor ->
if valid_block then begin
debug w
"ignoring previously validated block %a from peer %a"
Block_hash.pp_short hash
P2p_peer.Id.pp_short pv.peer_id ;
set_bootstrapped pv ;
pv.last_validated_head <- header ;
return ()
end else if invalid_block then begin
debug w
"ignoring known invalid block %a from peer %a"
Block_hash.pp_short hash
P2p_peer.Id.pp_short pv.peer_id ;
fail Validation_errors.Known_invalid
end else if invalid_predecessor then begin
debug w
"ignoring known invalid block %a from peer %a"
Block_hash.pp_short hash
P2p_peer.Id.pp_short pv.peer_id ;
Distributed_db.commit_invalid_block pv.parameters.chain_db
hash header [Validation_errors.Known_invalid] >>=? fun _ ->
fail Validation_errors.Known_invalid
end else if not valid_predecessor then begin
debug w
"missing predecessor for new head %a from peer %a"
Block_hash.pp_short hash
P2p_peer.Id.pp_short pv.peer_id ;
Distributed_db.Request.current_branch
pv.parameters.chain_db ~peer:pv.peer_id () ;
return ()
end else begin
only_if_fitness_increases w header @@ fun () ->
assert_acceptable_head w hash header >>=? fun () ->
validate_new_head w hash header
end
let may_validate_new_branch w distant_hash locator =
let pv = Worker.state w in
let distant_header, _ = (locator : Block_locator.t :> Block_header.t * _) in
only_if_fitness_increases w distant_header @@ fun () ->
assert_acceptable_head w
(Block_header.hash distant_header) distant_header >>=? fun () ->
let chain_state = Distributed_db.chain_state pv.parameters.chain_db in
State.Block.known_ancestor chain_state locator >>= function
| None ->
debug w
"ignoring branch %a without common ancestor from peer: %a."
Block_hash.pp_short distant_hash
P2p_peer.Id.pp_short pv.peer_id ;
fail Validation_errors.Unknown_ancestor
| Some (ancestor, unknown_prefix) ->
bootstrap_new_branch w ancestor distant_header unknown_prefix
let on_no_request w =
let pv = Worker.state w in
debug w "no new head from peer %a for %g seconds."
P2p_peer.Id.pp_short pv.peer_id
pv.parameters.limits.new_head_request_timeout ;
Distributed_db.Request.current_head pv.parameters.chain_db ~peer:pv.peer_id () ;
return ()
let on_request (type a) w (req : a Request.t) : a tzresult Lwt.t =
let pv = Worker.state w in
match req with
| Request.New_head (hash, header) ->
debug w
"processing new head %a from peer %a."
Block_hash.pp_short hash
P2p_peer.Id.pp_short pv.peer_id ;
may_validate_new_head w hash header
| Request.New_branch (hash, locator, _seed) ->
(* TODO penalize empty locator... ?? *)
debug w "processing new branch %a from peer %a."
Block_hash.pp_short hash
P2p_peer.Id.pp_short pv.peer_id ;
may_validate_new_branch w hash locator
let on_completion w r _ st =
Worker.record_event w (Event.Request (Request.view r, st, None )) ;
Lwt.return ()
let on_error w r st errs =
let pv = Worker.state w in
match errs with
((( Validation_errors.Unknown_ancestor
| Validation_errors.Invalid_locator _
| Block_validator_errors.Invalid_block _ ) :: _) as errors ) ->
Distributed_db.greylist pv.parameters.chain_db pv.peer_id >>= fun () ->
debug w
"Terminating the validation worker for peer %a (kickban)."
P2p_peer.Id.pp_short pv.peer_id ;
debug w "%a" Error_monad.pp_print_error errors ;
Worker.trigger_shutdown w ;
Worker.record_event w (Event.Request (r, st, Some errs)) ;
Lwt.return (Error errs)
| [Block_validator_errors.Unavailable_protocol { protocol } ] -> begin
Block_validator.fetch_and_compile_protocol
pv.parameters.block_validator
~peer:pv.peer_id
~timeout:pv.parameters.limits.protocol_timeout
protocol >>= function
| Ok _ ->
Distributed_db.Request.current_head
pv.parameters.chain_db ~peer:pv.peer_id () ;
return ()
| Error _ ->
(* TODO: punish *)
debug w
"Terminating the validation worker for peer %a \
(missing protocol %a)."
P2p_peer.Id.pp_short pv.peer_id
Protocol_hash.pp_short protocol ;
Worker.record_event w (Event.Request (r, st, Some errs)) ;
Lwt.return (Error errs)
end
| _ ->
Worker.record_event w (Event.Request (r, st, Some errs)) ;
Lwt.return (Error errs)
let on_close w =
let pv = Worker.state w in
Distributed_db.disconnect pv.parameters.chain_db pv.peer_id >>= fun () ->
pv.parameters.notify_termination () ;
Lwt.return ()
let on_launch _ name parameters =
let chain_state = Distributed_db.chain_state parameters.chain_db in
State.Block.read_exn chain_state
(State.Chain.genesis chain_state).block >>= fun genesis ->
let rec pv = {
peer_id = snd name ;
parameters = { parameters with notify_new_block } ;
bootstrapped = false ;
last_validated_head = State.Block.header genesis ;
last_advertised_head = State.Block.header genesis ;
}
and notify_new_block block =
pv.last_validated_head <- State.Block.header block ;
parameters.notify_new_block block in
Lwt.return pv
let table =
let merge w (Worker.Any_request neu) old =
let pv = Worker.state w in
match neu with
| Request.New_branch (_, locator, _) ->
let header, _ = (locator : Block_locator.t :> _ * _) in
pv.last_advertised_head <- header ;
Some (Worker.Any_request neu)
| Request.New_head (_, header) ->
pv.last_advertised_head <- header ;
(* TODO penalize decreasing fitness *)
match old with
| Some (Worker.Any_request (Request.New_branch _) as old) ->
Some old (* ignore *)
| Some (Worker.Any_request (Request.New_head _)) ->
Some (Any_request neu)
| None ->
Some (Any_request neu) in
Worker.create_table (Dropbox { merge })
let create
?(notify_new_block = fun _ -> ())
?(notify_bootstrapped = fun () -> ())
?(notify_termination = fun _ -> ())
limits block_validator chain_db peer_id =
let name = (State.Chain.id (Distributed_db.chain_state chain_db), peer_id) in
let parameters = {
chain_db ;
notify_termination ;
block_validator ;
notify_new_block ;
notify_bootstrapped ;
limits ;
} in
let module Handlers = struct
type self = t
let on_launch = on_launch
let on_request = on_request
let on_close = on_close
let on_error = on_error
let on_completion = on_completion
let on_no_request _ = return ()
end in
Worker.launch table ~timeout: limits.new_head_request_timeout limits.worker_limits
name parameters
(module Handlers)
let notify_branch w locator =
let header, _ = (locator : Block_locator.t :> _ * _) in
let hash = Block_header.hash header in
let pv = Worker.state w in
let sender_id = Distributed_db.my_peer_id pv.parameters.chain_db in
(* sender and receiver are inverted here because they are from
the point of view of the node sending the locator *)
let seed = {Block_locator.sender_id=pv.peer_id; receiver_id=sender_id } in
Worker.drop_request w (New_branch (hash, locator, seed))
let notify_head w header =
let hash = Block_header.hash header in
Worker.drop_request w (New_head (hash, header))
let shutdown w =
Worker.shutdown w
let peer_id w =
let pv = Worker.state w in
pv.peer_id
let bootstrapped w =
let pv = Worker.state w in
pv.bootstrapped
let current_head w =
let pv = Worker.state w in
pv.last_validated_head
let status = Worker.status
let running_workers () = Worker.list table
let current_request t = Worker.current_request t
let last_events = Worker.last_events