src/core/ext/transport/chttp2/server/chttp2_server.cc

   1 /*
   2  *
   3  * Copyright 2015 gRPC authors.
   4  *
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at
   8  *
   9  *     http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  *
  17  */
  18
  19 #include <grpc/support/port_platform.h>
  20
  21 #include "src/core/ext/transport/chttp2/server/chttp2_server.h"
  22
  23 #include <inttypes.h>
  24 #include <limits.h>
  25 #include <string.h>
  26 #include <vector>
  27
  28 #include "absl/strings/str_cat.h"
  29 #include "absl/strings/str_format.h"
  30
  31 #include <grpc/grpc.h>
  32 #include <grpc/impl/codegen/grpc_types.h>
  33 #include <grpc/support/alloc.h>
  34 #include <grpc/support/log.h>
  35 #include <grpc/support/sync.h>
  36
  37 #include "src/core/ext/filters/http/server/http_server_filter.h"
  38 #include "src/core/ext/transport/chttp2/transport/chttp2_transport.h"
  39 #include "src/core/ext/transport/chttp2/transport/internal.h"
  40 #include "src/core/lib/channel/channel_args.h"
  41 #include "src/core/lib/channel/handshaker.h"
  42 #include "src/core/lib/channel/handshaker_registry.h"
  43 #include "src/core/lib/gprpp/ref_counted.h"
  44 #include "src/core/lib/gprpp/ref_counted_ptr.h"
  45 #include "src/core/lib/iomgr/endpoint.h"
  46 #include "src/core/lib/iomgr/resolve_address.h"
  47 #include "src/core/lib/iomgr/resource_quota.h"
  48 #include "src/core/lib/iomgr/tcp_server.h"
  49 #include "src/core/lib/slice/slice_internal.h"
  50 #include "src/core/lib/surface/api_trace.h"
  51 #include "src/core/lib/surface/server.h"
  52
  53 namespace grpc_core {
  54 namespace {
  55
  56 class Chttp2ServerListener : public Server::ListenerInterface {
  57  public:
  58   static grpc_error* Create(Server* server, const char* addr,
  59                             grpc_channel_args* args, int* port_num);
  60
  61   static grpc_error* CreateWithAcceptor(Server* server, const char* name,
  62                                         grpc_channel_args* args);
  63
  64   // Do not instantiate directly.  Use one of the factory methods above.
  65   Chttp2ServerListener(Server* server, grpc_channel_args* args);
  66   ~Chttp2ServerListener();
  67
  68   void Start(Server* server,
  69              const std::vector<grpc_pollset*>* pollsets) override;
  70
  71   channelz::ListenSocketNode* channelz_listen_socket_node() const override {
  72     return channelz_listen_socket_.get();
  73   }
  74
  75   void SetOnDestroyDone(grpc_closure* on_destroy_done) override;
  76
  77   void Orphan() override;
  78
  79  private:
  80   class ConnectionState : public RefCounted<ConnectionState> {
  81    public:
  82     ConnectionState(Chttp2ServerListener* listener,
  83                     grpc_pollset* accepting_pollset,
  84                     grpc_tcp_server_acceptor* acceptor,
  85                     RefCountedPtr<HandshakeManager> handshake_mgr,
  86                     grpc_channel_args* args, grpc_endpoint* endpoint);
  87
  88     ~ConnectionState();
  89
  90    private:
  91     static void OnTimeout(void* arg, grpc_error* error);
  92     static void OnReceiveSettings(void* arg, grpc_error* error);
  93     static void OnHandshakeDone(void* arg, grpc_error* error);
  94
  95     Chttp2ServerListener* const listener_;
  96     grpc_pollset* const accepting_pollset_;
  97     grpc_tcp_server_acceptor* const acceptor_;
  98     RefCountedPtr<HandshakeManager> handshake_mgr_;
  99     // State for enforcing handshake timeout on receiving HTTP/2 settings.
 100     grpc_chttp2_transport* transport_ = nullptr;
 101     grpc_millis deadline_;
 102     grpc_timer timer_;
 103     grpc_closure on_timeout_;
 104     grpc_closure on_receive_settings_;
 105     grpc_pollset_set* const interested_parties_;
 106   };
 107
 108   static void OnAccept(void* arg, grpc_endpoint* tcp,
 109                        grpc_pollset* accepting_pollset,
 110                        grpc_tcp_server_acceptor* acceptor);
 111
 112   RefCountedPtr<HandshakeManager> CreateHandshakeManager();
 113
 114   static void TcpServerShutdownComplete(void* arg, grpc_error* error);
 115
 116   static void DestroyListener(Server* /*server*/, void* arg,
 117                               grpc_closure* destroy_done);
 118
 119   Server* const server_;
 120   grpc_channel_args* const args_;
 121   grpc_tcp_server* tcp_server_;
 122   Mutex mu_;
 123   bool shutdown_ = true;
 124   grpc_closure tcp_server_shutdown_complete_;
 125   grpc_closure* on_destroy_done_ = nullptr;
 126   HandshakeManager* pending_handshake_mgrs_ = nullptr;
 127   RefCountedPtr<channelz::ListenSocketNode> channelz_listen_socket_;
 128 };
 129
 130 //
 131 // Chttp2ServerListener::ConnectionState
 132 //
 133
 134 grpc_millis GetConnectionDeadline(const grpc_channel_args* args) {
 135   int timeout_ms =
 136       grpc_channel_args_find_integer(args, GRPC_ARG_SERVER_HANDSHAKE_TIMEOUT_MS,
 137                                      {120 * GPR_MS_PER_SEC, 1, INT_MAX});
 138   return ExecCtx::Get()->Now() + timeout_ms;
 139 }
 140
 141 Chttp2ServerListener::ConnectionState::ConnectionState(
 142     Chttp2ServerListener* listener, grpc_pollset* accepting_pollset,
 143     grpc_tcp_server_acceptor* acceptor,
 144     RefCountedPtr<HandshakeManager> handshake_mgr, grpc_channel_args* args,
 145     grpc_endpoint* endpoint)
 146     : listener_(listener),
 147       accepting_pollset_(accepting_pollset),
 148       acceptor_(acceptor),
 149       handshake_mgr_(std::move(handshake_mgr)),
 150       deadline_(GetConnectionDeadline(args)),
 151       interested_parties_(grpc_pollset_set_create()) {
 152   grpc_pollset_set_add_pollset(interested_parties_, accepting_pollset_);
 153   HandshakerRegistry::AddHandshakers(HANDSHAKER_SERVER, args,
 154                                      interested_parties_, handshake_mgr_.get());
 155   handshake_mgr_->DoHandshake(endpoint, args, deadline_, acceptor_,
 156                               OnHandshakeDone, this);
 157 }
 158
 159 Chttp2ServerListener::ConnectionState::~ConnectionState() {
 160   if (transport_ != nullptr) {
 161     GRPC_CHTTP2_UNREF_TRANSPORT(transport_, "receive settings timeout");
 162   }
 163   grpc_pollset_set_del_pollset(interested_parties_, accepting_pollset_);
 164   grpc_pollset_set_destroy(interested_parties_);
 165 }
 166
 167 void Chttp2ServerListener::ConnectionState::OnTimeout(void* arg,
 168                                                       grpc_error* error) {
 169   ConnectionState* self = static_cast<ConnectionState*>(arg);
 170   // Note that we may be called with GRPC_ERROR_NONE when the timer fires
 171   // or with an error indicating that the timer system is being shut down.
 172   if (error != GRPC_ERROR_CANCELLED) {
 173     grpc_transport_op* op = grpc_make_transport_op(nullptr);
 174     op->disconnect_with_error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
 175         "Did not receive HTTP/2 settings before handshake timeout");
 176     grpc_transport_perform_op(&self->transport_->base, op);
 177   }
 178   self->Unref();
 179 }
 180
 181 void Chttp2ServerListener::ConnectionState::OnReceiveSettings(
 182     void* arg, grpc_error* error) {
 183   ConnectionState* self = static_cast<ConnectionState*>(arg);
 184   if (error == GRPC_ERROR_NONE) {
 185     grpc_timer_cancel(&self->timer_);
 186   }
 187   self->Unref();
 188 }
 189
 190 void Chttp2ServerListener::ConnectionState::OnHandshakeDone(void* arg,
 191                                                             grpc_error* error) {
 192   auto* args = static_cast<HandshakerArgs*>(arg);
 193   ConnectionState* self = static_cast<ConnectionState*>(args->user_data);
 194   {
 195     MutexLock lock(&self->listener_->mu_);
 196     grpc_resource_user* resource_user =
 197         self->listener_->server_->default_resource_user();
 198     if (error != GRPC_ERROR_NONE || self->listener_->shutdown_) {
 199       const char* error_str = grpc_error_string(error);
 200       gpr_log(GPR_DEBUG, "Handshaking failed: %s", error_str);
 201       if (resource_user != nullptr) {
 202         grpc_resource_user_free(resource_user,
 203                                 GRPC_RESOURCE_QUOTA_CHANNEL_SIZE);
 204       }
 205       if (error == GRPC_ERROR_NONE && args->endpoint != nullptr) {
 206         // We were shut down after handshaking completed successfully, so
 207         // destroy the endpoint here.
 208         // TODO(ctiller): It is currently necessary to shutdown endpoints
 209         // before destroying them, even if we know that there are no
 210         // pending read/write callbacks.  This should be fixed, at which
 211         // point this can be removed.
 212         grpc_endpoint_shutdown(args->endpoint, GRPC_ERROR_NONE);
 213         grpc_endpoint_destroy(args->endpoint);
 214         grpc_channel_args_destroy(args->args);
 215         grpc_slice_buffer_destroy_internal(args->read_buffer);
 216         gpr_free(args->read_buffer);
 217       }
 218     } else {
 219       // If the handshaking succeeded but there is no endpoint, then the
 220       // handshaker may have handed off the connection to some external
 221       // code, so we can just clean up here without creating a transport.
 222       if (args->endpoint != nullptr) {
 223         grpc_transport* transport = grpc_create_chttp2_transport(
 224             args->args, args->endpoint, false, resource_user);
 225         self->listener_->server_->SetupTransport(
 226             transport, self->accepting_pollset_, args->args,
 227             grpc_chttp2_transport_get_socket_node(transport), resource_user);
 228         // Use notify_on_receive_settings callback to enforce the
 229         // handshake deadline.
 230         // Note: The reinterpret_cast<>s here are safe, because
 231         // grpc_chttp2_transport is a C-style extension of
 232         // grpc_transport, so this is morally equivalent of a
 233         // static_cast<> to a derived class.
 234         // TODO(roth): Change to static_cast<> when we C++-ify the
 235         // transport API.
 236         self->transport_ = reinterpret_cast<grpc_chttp2_transport*>(transport);
 237         self->Ref().release();  // Held by OnReceiveSettings().
 238         GRPC_CLOSURE_INIT(&self->on_receive_settings_, OnReceiveSettings, self,
 239                           grpc_schedule_on_exec_ctx);
 240         grpc_chttp2_transport_start_reading(transport, args->read_buffer,
 241                                             &self->on_receive_settings_);
 242         grpc_channel_args_destroy(args->args);
 243         self->Ref().release();  // Held by OnTimeout().
 244         GRPC_CHTTP2_REF_TRANSPORT(
 245             reinterpret_cast<grpc_chttp2_transport*>(transport),
 246             "receive settings timeout");
 247         GRPC_CLOSURE_INIT(&self->on_timeout_, OnTimeout, self,
 248                           grpc_schedule_on_exec_ctx);
 249         grpc_timer_init(&self->timer_, self->deadline_, &self->on_timeout_);
 250       } else {
 251         if (resource_user != nullptr) {
 252           grpc_resource_user_free(resource_user,
 253                                   GRPC_RESOURCE_QUOTA_CHANNEL_SIZE);
 254         }
 255       }
 256     }
 257     self->handshake_mgr_->RemoveFromPendingMgrList(
 258         &self->listener_->pending_handshake_mgrs_);
 259   }
 260   self->handshake_mgr_.reset();
 261   gpr_free(self->acceptor_);
 262   grpc_tcp_server_unref(self->listener_->tcp_server_);
 263   self->Unref();
 264 }
 265
 266 //
 267 // Chttp2ServerListener
 268 //
 269
 270 grpc_error* Chttp2ServerListener::Create(Server* server, const char* addr,
 271                                          grpc_channel_args* args,
 272                                          int* port_num) {
 273   std::vector<grpc_error*> error_list;
 274   grpc_resolved_addresses* resolved = nullptr;
 275   Chttp2ServerListener* listener = nullptr;
 276   // The bulk of this method is inside of a lambda to make cleanup
 277   // easier without using goto.
 278   grpc_error* error = [&]() {
 279     *port_num = -1;
 280     /* resolve address */
 281     grpc_error* error = grpc_blocking_resolve_address(addr, "https", &resolved);
 282     if (error != GRPC_ERROR_NONE) return error;
 283     // Create Chttp2ServerListener.
 284     listener = new Chttp2ServerListener(server, args);
 285     error = grpc_tcp_server_create(&listener->tcp_server_shutdown_complete_,
 286                                    args, &listener->tcp_server_);
 287     if (error != GRPC_ERROR_NONE) return error;
 288     for (size_t i = 0; i < resolved->naddrs; i++) {
 289       int port_temp;
 290       error = grpc_tcp_server_add_port(listener->tcp_server_,
 291                                        &resolved->addrs[i], &port_temp);
 292       if (error != GRPC_ERROR_NONE) {
 293         error_list.push_back(error);
 294       } else {
 295         if (*port_num == -1) {
 296           *port_num = port_temp;
 297         } else {
 298           GPR_ASSERT(*port_num == port_temp);
 299         }
 300       }
 301     }
 302     if (error_list.size() == resolved->naddrs) {
 303       std::string msg =
 304           absl::StrFormat("No address added out of total %" PRIuPTR " resolved",
 305                           resolved->naddrs);
 306       return GRPC_ERROR_CREATE_REFERENCING_FROM_COPIED_STRING(
 307           msg.c_str(), error_list.data(), error_list.size());
 308     } else if (!error_list.empty()) {
 309       std::string msg = absl::StrFormat(
 310           "Only %" PRIuPTR " addresses added out of total %" PRIuPTR
 311           " resolved",
 312           resolved->naddrs - error_list.size(), resolved->naddrs);
 313       error = GRPC_ERROR_CREATE_REFERENCING_FROM_COPIED_STRING(
 314           msg.c_str(), error_list.data(), error_list.size());
 315       gpr_log(GPR_INFO, "WARNING: %s", grpc_error_string(error));
 316       GRPC_ERROR_UNREF(error);
 317       /* we managed to bind some addresses: continue */
 318     }
 319     // Create channelz node.
 320     if (grpc_channel_args_find_bool(args, GRPC_ARG_ENABLE_CHANNELZ,
 321                                     GRPC_ENABLE_CHANNELZ_DEFAULT)) {
 322       listener->channelz_listen_socket_ =
 323           MakeRefCounted<channelz::ListenSocketNode>(
 324               addr, absl::StrFormat("chttp2 listener %s", addr));
 325     }
 326     /* Register with the server only upon success */
 327     server->AddListener(OrphanablePtr<Server::ListenerInterface>(listener));
 328     return GRPC_ERROR_NONE;
 329   }();
 330   if (resolved != nullptr) {
 331     grpc_resolved_addresses_destroy(resolved);
 332   }
 333   if (error != GRPC_ERROR_NONE) {
 334     if (listener != nullptr) {
 335       if (listener->tcp_server_ != nullptr) {
 336         grpc_tcp_server_unref(listener->tcp_server_);
 337       } else {
 338         delete listener;
 339       }
 340     } else {
 341       grpc_channel_args_destroy(args);
 342     }
 343     *port_num = 0;
 344   }
 345   for (grpc_error* error : error_list) {
 346     GRPC_ERROR_UNREF(error);
 347   }
 348   return error;
 349 }
 350
 351 grpc_error* Chttp2ServerListener::CreateWithAcceptor(Server* server,
 352                                                      const char* name,
 353                                                      grpc_channel_args* args) {
 354   Chttp2ServerListener* listener = new Chttp2ServerListener(server, args);
 355   grpc_error* error = grpc_tcp_server_create(
 356       &listener->tcp_server_shutdown_complete_, args, &listener->tcp_server_);
 357   if (error != GRPC_ERROR_NONE) {
 358     delete listener;
 359     return error;
 360   }
 361   // TODO(yangg) channelz
 362   TcpServerFdHandler** arg_val =
 363       grpc_channel_args_find_pointer<TcpServerFdHandler*>(args, name);
 364   *arg_val = grpc_tcp_server_create_fd_handler(listener->tcp_server_);
 365   server->AddListener(OrphanablePtr<Server::ListenerInterface>(listener));
 366   return GRPC_ERROR_NONE;
 367 }
 368
 369 Chttp2ServerListener::Chttp2ServerListener(Server* server,
 370                                            grpc_channel_args* args)
 371     : server_(server), args_(args) {
 372   GRPC_CLOSURE_INIT(&tcp_server_shutdown_complete_, TcpServerShutdownComplete,
 373                     this, grpc_schedule_on_exec_ctx);
 374 }
 375
 376 Chttp2ServerListener::~Chttp2ServerListener() {
 377   grpc_channel_args_destroy(args_);
 378 }
 379
 380 /* Server callback: start listening on our ports */
 381 void Chttp2ServerListener::Start(Server* /*server*/,
 382                                  const std::vector<grpc_pollset*>* pollsets) {
 383   {
 384     MutexLock lock(&mu_);
 385     shutdown_ = false;
 386   }
 387   grpc_tcp_server_start(tcp_server_, pollsets, OnAccept, this);
 388 }
 389
 390 void Chttp2ServerListener::SetOnDestroyDone(grpc_closure* on_destroy_done) {
 391   MutexLock lock(&mu_);
 392   on_destroy_done_ = on_destroy_done;
 393 }
 394
 395 RefCountedPtr<HandshakeManager> Chttp2ServerListener::CreateHandshakeManager() {
 396   MutexLock lock(&mu_);
 397   if (shutdown_) return nullptr;
 398   grpc_resource_user* resource_user = server_->default_resource_user();
 399   if (resource_user != nullptr &&
 400       !grpc_resource_user_safe_alloc(resource_user,
 401                                      GRPC_RESOURCE_QUOTA_CHANNEL_SIZE)) {
 402     gpr_log(GPR_ERROR,
 403             "Memory quota exhausted, rejecting connection, no handshaking.");
 404     return nullptr;
 405   }
 406   auto handshake_mgr = MakeRefCounted<HandshakeManager>();
 407   handshake_mgr->AddToPendingMgrList(&pending_handshake_mgrs_);
 408   grpc_tcp_server_ref(tcp_server_);  // Ref held by ConnectionState.
 409   return handshake_mgr;
 410 }
 411
 412 void Chttp2ServerListener::OnAccept(void* arg, grpc_endpoint* tcp,
 413                                     grpc_pollset* accepting_pollset,
 414                                     grpc_tcp_server_acceptor* acceptor) {
 415   Chttp2ServerListener* self = static_cast<Chttp2ServerListener*>(arg);
 416   RefCountedPtr<HandshakeManager> handshake_mgr =
 417       self->CreateHandshakeManager();
 418   if (handshake_mgr == nullptr) {
 419     grpc_endpoint_shutdown(tcp, GRPC_ERROR_NONE);
 420     grpc_endpoint_destroy(tcp);
 421     gpr_free(acceptor);
 422     return;
 423   }
 424   // Deletes itself when done.
 425   new ConnectionState(self, accepting_pollset, acceptor,
 426                       std::move(handshake_mgr), self->args_, tcp);
 427 }
 428
 429 void Chttp2ServerListener::TcpServerShutdownComplete(void* arg,
 430                                                      grpc_error* error) {
 431   Chttp2ServerListener* self = static_cast<Chttp2ServerListener*>(arg);
 432   /* ensure all threads have unlocked */
 433   grpc_closure* destroy_done = nullptr;
 434   {
 435     MutexLock lock(&self->mu_);
 436     destroy_done = self->on_destroy_done_;
 437     GPR_ASSERT(self->shutdown_);
 438     if (self->pending_handshake_mgrs_ != nullptr) {
 439       self->pending_handshake_mgrs_->ShutdownAllPending(GRPC_ERROR_REF(error));
 440     }
 441     self->channelz_listen_socket_.reset();
 442   }
 443   // Flush queued work before destroying handshaker factory, since that
 444   // may do a synchronous unref.
 445   ExecCtx::Get()->Flush();
 446   if (destroy_done != nullptr) {
 447     ExecCtx::Run(DEBUG_LOCATION, destroy_done, GRPC_ERROR_REF(error));
 448     ExecCtx::Get()->Flush();
 449   }
 450   delete self;
 451 }
 452
 453 /* Server callback: destroy the tcp listener (so we don't generate further
 454    callbacks) */
 455 void Chttp2ServerListener::Orphan() {
 456   grpc_tcp_server* tcp_server;
 457   {
 458     MutexLock lock(&mu_);
 459     shutdown_ = true;
 460     tcp_server = tcp_server_;
 461   }
 462   grpc_tcp_server_shutdown_listeners(tcp_server);
 463   grpc_tcp_server_unref(tcp_server);
 464 }
 465
 466 }  // namespace
 467
 468 //
 469 // Chttp2ServerAddPort()
 470 //
 471
 472 grpc_error* Chttp2ServerAddPort(Server* server, const char* addr,
 473                                 grpc_channel_args* args, int* port_num) {
 474   if (strncmp(addr, "external:", 9) == 0) {
 475     return grpc_core::Chttp2ServerListener::CreateWithAcceptor(server, addr,
 476                                                                args);
 477   }
 478   return grpc_core::Chttp2ServerListener::Create(server, addr, args, port_num);
 479 }
 480
 481 }  // namespace grpc_core