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
27#include <grpc/grpc.h>
28#include <grpc/impl/codegen/grpc_types.h>
29#include <grpc/support/alloc.h>
30#include <grpc/support/log.h>
31#include <grpc/support/string_util.h>
32#include <grpc/support/sync.h>
33
34#include "src/core/ext/filters/http/server/http_server_filter.h"
35#include "src/core/ext/transport/chttp2/transport/chttp2_transport.h"
36#include "src/core/ext/transport/chttp2/transport/internal.h"
37#include "src/core/lib/channel/channel_args.h"
38#include "src/core/lib/channel/handshaker.h"
39#include "src/core/lib/channel/handshaker_registry.h"
40#include "src/core/lib/iomgr/endpoint.h"
41#include "src/core/lib/iomgr/resolve_address.h"
42#include "src/core/lib/iomgr/resource_quota.h"
43#include "src/core/lib/iomgr/tcp_server.h"
44#include "src/core/lib/slice/slice_internal.h"
45#include "src/core/lib/surface/api_trace.h"
46#include "src/core/lib/surface/server.h"
47
48typedef struct {
49 grpc_server* server;
50 grpc_tcp_server* tcp_server;
51 grpc_channel_args* args;
52 gpr_mu mu;
53 bool shutdown;
54 grpc_closure tcp_server_shutdown_complete;
55 grpc_closure* server_destroy_listener_done;
56 grpc_core::HandshakeManager* pending_handshake_mgrs;
57 grpc_core::RefCountedPtr<grpc_core::channelz::ListenSocketNode>
58 channelz_listen_socket;
59} server_state;
60
61typedef struct {
62 gpr_refcount refs;
63 server_state* svr_state;
64 grpc_pollset* accepting_pollset;
65 grpc_tcp_server_acceptor* acceptor;
66 grpc_core::RefCountedPtr<grpc_core::HandshakeManager> handshake_mgr;
67 // State for enforcing handshake timeout on receiving HTTP/2 settings.
68 grpc_chttp2_transport* transport;
69 grpc_millis deadline;
70 grpc_timer timer;
71 grpc_closure on_timeout;
72 grpc_closure on_receive_settings;
73 grpc_pollset_set* interested_parties;
74} server_connection_state;
75
76static void server_connection_state_unref(
77 server_connection_state* connection_state) {
78 if (gpr_unref(&connection_state->refs)) {
79 if (connection_state->transport != nullptr) {
80 GRPC_CHTTP2_UNREF_TRANSPORT(connection_state->transport,
81 "receive settings timeout");
82 }
83 grpc_pollset_set_del_pollset(connection_state->interested_parties,
84 connection_state->accepting_pollset);
85 grpc_pollset_set_destroy(connection_state->interested_parties);
86 gpr_free(connection_state);
87 }
88}
89
90static void on_timeout(void* arg, grpc_error* error) {
91 server_connection_state* connection_state =
92 static_cast<server_connection_state*>(arg);
93 // Note that we may be called with GRPC_ERROR_NONE when the timer fires
94 // or with an error indicating that the timer system is being shut down.
95 if (error != GRPC_ERROR_CANCELLED) {
96 grpc_transport_op* op = grpc_make_transport_op(nullptr);
97 op->disconnect_with_error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
98 "Did not receive HTTP/2 settings before handshake timeout");
99 grpc_transport_perform_op(&connection_state->transport->base, op);
100 }
101 server_connection_state_unref(connection_state);
102}
103
104static void on_receive_settings(void* arg, grpc_error* error) {
105 server_connection_state* connection_state =
106 static_cast<server_connection_state*>(arg);
107 if (error == GRPC_ERROR_NONE) {
108 grpc_timer_cancel(&connection_state->timer);
109 }
110 server_connection_state_unref(connection_state);
111}
112
113static void on_handshake_done(void* arg, grpc_error* error) {
114 auto* args = static_cast<grpc_core::HandshakerArgs*>(arg);
115 server_connection_state* connection_state =
116 static_cast<server_connection_state*>(args->user_data);
117 gpr_mu_lock(&connection_state->svr_state->mu);
118 grpc_resource_user* resource_user = grpc_server_get_default_resource_user(
119 connection_state->svr_state->server);
120 if (error != GRPC_ERROR_NONE || connection_state->svr_state->shutdown) {
121 const char* error_str = grpc_error_string(error);
122 gpr_log(GPR_DEBUG, "Handshaking failed: %s", error_str);
123 grpc_resource_user* resource_user = grpc_server_get_default_resource_user(
124 connection_state->svr_state->server);
125 if (resource_user != nullptr) {
126 grpc_resource_user_free(resource_user, GRPC_RESOURCE_QUOTA_CHANNEL_SIZE);
127 }
128 if (error == GRPC_ERROR_NONE && args->endpoint != nullptr) {
129 // We were shut down after handshaking completed successfully, so
130 // destroy the endpoint here.
131 // TODO(ctiller): It is currently necessary to shutdown endpoints
132 // before destroying them, even if we know that there are no
133 // pending read/write callbacks. This should be fixed, at which
134 // point this can be removed.
135 grpc_endpoint_shutdown(args->endpoint, GRPC_ERROR_NONE);
136 grpc_endpoint_destroy(args->endpoint);
137 grpc_channel_args_destroy(args->args);
138 grpc_slice_buffer_destroy_internal(args->read_buffer);
139 gpr_free(args->read_buffer);
140 }
141 } else {
142 // If the handshaking succeeded but there is no endpoint, then the
143 // handshaker may have handed off the connection to some external
144 // code, so we can just clean up here without creating a transport.
145 if (args->endpoint != nullptr) {
146 grpc_transport* transport = grpc_create_chttp2_transport(
147 args->args, args->endpoint, false, resource_user);
148 grpc_server_setup_transport(
149 connection_state->svr_state->server, transport,
150 connection_state->accepting_pollset, args->args,
151 grpc_chttp2_transport_get_socket_node(transport), resource_user);
152 // Use notify_on_receive_settings callback to enforce the
153 // handshake deadline.
154 connection_state->transport =
155 reinterpret_cast<grpc_chttp2_transport*>(transport);
156 gpr_ref(&connection_state->refs);
157 GRPC_CLOSURE_INIT(&connection_state->on_receive_settings,
158 on_receive_settings, connection_state,
159 grpc_schedule_on_exec_ctx);
160 grpc_chttp2_transport_start_reading(
161 transport, args->read_buffer, &connection_state->on_receive_settings);
162 grpc_channel_args_destroy(args->args);
163 gpr_ref(&connection_state->refs);
164 GRPC_CHTTP2_REF_TRANSPORT((grpc_chttp2_transport*)transport,
165 "receive settings timeout");
166 GRPC_CLOSURE_INIT(&connection_state->on_timeout, on_timeout,
167 connection_state, grpc_schedule_on_exec_ctx);
168 grpc_timer_init(&connection_state->timer, connection_state->deadline,
169 &connection_state->on_timeout);
170 } else {
171 if (resource_user != nullptr) {
172 grpc_resource_user_free(resource_user,
173 GRPC_RESOURCE_QUOTA_CHANNEL_SIZE);
174 }
175 }
176 }
177 connection_state->handshake_mgr->RemoveFromPendingMgrList(
178 &connection_state->svr_state->pending_handshake_mgrs);
179 gpr_mu_unlock(&connection_state->svr_state->mu);
180 connection_state->handshake_mgr.reset();
181 gpr_free(connection_state->acceptor);
182 grpc_tcp_server_unref(connection_state->svr_state->tcp_server);
183 server_connection_state_unref(connection_state);
184}
185
186static void on_accept(void* arg, grpc_endpoint* tcp,
187 grpc_pollset* accepting_pollset,
188 grpc_tcp_server_acceptor* acceptor) {
189 server_state* state = static_cast<server_state*>(arg);
190 gpr_mu_lock(&state->mu);
191 if (state->shutdown) {
192 gpr_mu_unlock(&state->mu);
193 grpc_endpoint_shutdown(tcp, GRPC_ERROR_NONE);
194 grpc_endpoint_destroy(tcp);
195 gpr_free(acceptor);
196 return;
197 }
198 grpc_resource_user* resource_user =
199 grpc_server_get_default_resource_user(state->server);
200 if (resource_user != nullptr &&
201 !grpc_resource_user_safe_alloc(resource_user,
202 GRPC_RESOURCE_QUOTA_CHANNEL_SIZE)) {
203 gpr_log(
204 GPR_ERROR,
205 "Memory quota exhausted, rejecting the connection, no handshaking.");
206 gpr_mu_unlock(&state->mu);
207 grpc_endpoint_shutdown(tcp, GRPC_ERROR_NONE);
208 grpc_endpoint_destroy(tcp);
209 gpr_free(acceptor);
210 return;
211 }
212 auto handshake_mgr = grpc_core::MakeRefCounted<grpc_core::HandshakeManager>();
213 handshake_mgr->AddToPendingMgrList(&state->pending_handshake_mgrs);
214 grpc_tcp_server_ref(state->tcp_server);
215 gpr_mu_unlock(&state->mu);
216 server_connection_state* connection_state =
217 static_cast<server_connection_state*>(
218 gpr_zalloc(sizeof(*connection_state)));
219 gpr_ref_init(&connection_state->refs, 1);
220 connection_state->svr_state = state;
221 connection_state->accepting_pollset = accepting_pollset;
222 connection_state->acceptor = acceptor;
223 connection_state->handshake_mgr = handshake_mgr;
224 connection_state->interested_parties = grpc_pollset_set_create();
225 grpc_pollset_set_add_pollset(connection_state->interested_parties,
226 connection_state->accepting_pollset);
227 grpc_core::HandshakerRegistry::AddHandshakers(
228 grpc_core::HANDSHAKER_SERVER, state->args,
229 connection_state->interested_parties,
230 connection_state->handshake_mgr.get());
231 const grpc_arg* timeout_arg =
232 grpc_channel_args_find(state->args, GRPC_ARG_SERVER_HANDSHAKE_TIMEOUT_MS);
233 connection_state->deadline =
234 grpc_core::ExecCtx::Get()->Now() +
235 grpc_channel_arg_get_integer(timeout_arg,
236 {120 * GPR_MS_PER_SEC, 1, INT_MAX});
237 connection_state->handshake_mgr->DoHandshake(
238 tcp, state->args, connection_state->deadline, acceptor, on_handshake_done,
239 connection_state);
240}
241
242/* Server callback: start listening on our ports */
243static void server_start_listener(grpc_server* /*server*/, void* arg,
244 grpc_pollset** pollsets,
245 size_t pollset_count) {
246 server_state* state = static_cast<server_state*>(arg);
247 gpr_mu_lock(&state->mu);
248 state->shutdown = false;
249 gpr_mu_unlock(&state->mu);
250 grpc_tcp_server_start(state->tcp_server, pollsets, pollset_count, on_accept,
251 state);
252}
253
254static void tcp_server_shutdown_complete(void* arg, grpc_error* error) {
255 server_state* state = static_cast<server_state*>(arg);
256 /* ensure all threads have unlocked */
257 gpr_mu_lock(&state->mu);
258 grpc_closure* destroy_done = state->server_destroy_listener_done;
259 GPR_ASSERT(state->shutdown);
260 if (state->pending_handshake_mgrs != nullptr) {
261 state->pending_handshake_mgrs->ShutdownAllPending(GRPC_ERROR_REF(error));
262 }
263 state->channelz_listen_socket.reset();
264 gpr_mu_unlock(&state->mu);
265 // Flush queued work before destroying handshaker factory, since that
266 // may do a synchronous unref.
267 grpc_core::ExecCtx::Get()->Flush();
268 if (destroy_done != nullptr) {
269 grpc_core::ExecCtx::Run(DEBUG_LOCATION, destroy_done,
270 GRPC_ERROR_REF(error));
271 grpc_core::ExecCtx::Get()->Flush();
272 }
273 grpc_channel_args_destroy(state->args);
274 gpr_mu_destroy(&state->mu);
275 gpr_free(state);
276}
277
278/* Server callback: destroy the tcp listener (so we don't generate further
279 callbacks) */
280static void server_destroy_listener(grpc_server* /*server*/, void* arg,
281 grpc_closure* destroy_done) {
282 server_state* state = static_cast<server_state*>(arg);
283 gpr_mu_lock(&state->mu);
284 state->shutdown = true;
285 state->server_destroy_listener_done = destroy_done;
286 grpc_tcp_server* tcp_server = state->tcp_server;
287 gpr_mu_unlock(&state->mu);
288 grpc_tcp_server_shutdown_listeners(tcp_server);
289 grpc_tcp_server_unref(tcp_server);
290}
291
292static grpc_error* chttp2_server_add_acceptor(grpc_server* server,
293 const char* name,
294 grpc_channel_args* args) {
295 grpc_tcp_server* tcp_server = nullptr;
296 grpc_error* err = GRPC_ERROR_NONE;
297 server_state* state = nullptr;
298 const grpc_arg* arg = nullptr;
299 grpc_core::TcpServerFdHandler** arg_val = nullptr;
300 state = static_cast<server_state*>(gpr_zalloc(sizeof(*state)));
301 GRPC_CLOSURE_INIT(&state->tcp_server_shutdown_complete,
302 tcp_server_shutdown_complete, state,
303 grpc_schedule_on_exec_ctx);
304 err = grpc_tcp_server_create(&state->tcp_server_shutdown_complete, args,
305 &tcp_server);
306 if (err != GRPC_ERROR_NONE) {
307 goto error;
308 }
309 state->server = server;
310 state->tcp_server = tcp_server;
311 state->args = args;
312 state->shutdown = true;
313 gpr_mu_init(&state->mu);
314 // TODO(yangg) channelz
315 arg = grpc_channel_args_find(args, name);
316 GPR_ASSERT(arg->type == GRPC_ARG_POINTER);
317 arg_val = static_cast<grpc_core::TcpServerFdHandler**>(arg->value.pointer.p);
318 *arg_val = grpc_tcp_server_create_fd_handler(tcp_server);
319
320 grpc_server_add_listener(server, state, server_start_listener,
321 server_destroy_listener, /* node */ nullptr);
322 return err;
323
324/* Error path: cleanup and return */
325error:
326 GPR_ASSERT(err != GRPC_ERROR_NONE);
327 if (tcp_server) {
328 grpc_tcp_server_unref(tcp_server);
329 } else {
330 grpc_channel_args_destroy(args);
331 gpr_free(state);
332 }
333 return err;
334}
335
336grpc_error* grpc_chttp2_server_add_port(grpc_server* server, const char* addr,
337 grpc_channel_args* args,
338 int* port_num) {
339 grpc_resolved_addresses* resolved = nullptr;
340 grpc_tcp_server* tcp_server = nullptr;
341 size_t i;
342 size_t count = 0;
343 int port_temp;
344 grpc_error* err = GRPC_ERROR_NONE;
345 server_state* state = nullptr;
346 grpc_error** errors = nullptr;
347 size_t naddrs = 0;
348 const grpc_arg* arg = nullptr;
349
350 *port_num = -1;
351
352 if (strncmp(addr, "external:", 9) == 0) {
353 return chttp2_server_add_acceptor(server, addr, args);
354 }
355
356 /* resolve address */
357 err = grpc_blocking_resolve_address(addr, "https", &resolved);
358 if (err != GRPC_ERROR_NONE) {
359 goto error;
360 }
361 state = static_cast<server_state*>(gpr_zalloc(sizeof(*state)));
362 GRPC_CLOSURE_INIT(&state->tcp_server_shutdown_complete,
363 tcp_server_shutdown_complete, state,
364 grpc_schedule_on_exec_ctx);
365 err = grpc_tcp_server_create(&state->tcp_server_shutdown_complete, args,
366 &tcp_server);
367 if (err != GRPC_ERROR_NONE) {
368 goto error;
369 }
370
371 state->server = server;
372 state->tcp_server = tcp_server;
373 state->args = args;
374 state->shutdown = true;
375 gpr_mu_init(&state->mu);
376
377 naddrs = resolved->naddrs;
378 errors = static_cast<grpc_error**>(gpr_malloc(sizeof(*errors) * naddrs));
379 for (i = 0; i < naddrs; i++) {
380 errors[i] =
381 grpc_tcp_server_add_port(tcp_server, &resolved->addrs[i], &port_temp);
382 if (errors[i] == GRPC_ERROR_NONE) {
383 if (*port_num == -1) {
384 *port_num = port_temp;
385 } else {
386 GPR_ASSERT(*port_num == port_temp);
387 }
388 count++;
389 }
390 }
391 if (count == 0) {
392 char* msg;
393 gpr_asprintf(&msg, "No address added out of total %" PRIuPTR " resolved",
394 naddrs);
395 err = GRPC_ERROR_CREATE_REFERENCING_FROM_COPIED_STRING(msg, errors, naddrs);
396 gpr_free(msg);
397 goto error;
398 } else if (count != naddrs) {
399 char* msg;
400 gpr_asprintf(&msg,
401 "Only %" PRIuPTR " addresses added out of total %" PRIuPTR
402 " resolved",
403 count, naddrs);
404 err = GRPC_ERROR_CREATE_REFERENCING_FROM_COPIED_STRING(msg, errors, naddrs);
405 gpr_free(msg);
406
407 const char* warning_message = grpc_error_string(err);
408 gpr_log(GPR_INFO, "WARNING: %s", warning_message);
409
410 /* we managed to bind some addresses: continue */
411 }
412 grpc_resolved_addresses_destroy(resolved);
413
414 arg = grpc_channel_args_find(args, GRPC_ARG_ENABLE_CHANNELZ);
415 if (grpc_channel_arg_get_bool(arg, GRPC_ENABLE_CHANNELZ_DEFAULT)) {
416 char* socket_name = nullptr;
417 gpr_asprintf(&socket_name, "chttp2 listener %s", addr);
418 state->channelz_listen_socket =
419 grpc_core::MakeRefCounted<grpc_core::channelz::ListenSocketNode>(
420 addr, socket_name);
421 // TODO(veblush): Remove this once gpr_asprintf is replaced by
422 // absl::StrFormat
423 gpr_free(socket_name);
424 }
425
426 /* Register with the server only upon success */
427 grpc_server_add_listener(server, state, server_start_listener,
428 server_destroy_listener,
429 state->channelz_listen_socket);
430 goto done;
431
432/* Error path: cleanup and return */
433error:
434 GPR_ASSERT(err != GRPC_ERROR_NONE);
435 if (resolved) {
436 grpc_resolved_addresses_destroy(resolved);
437 }
438 if (tcp_server) {
439 grpc_tcp_server_unref(tcp_server);
440 } else {
441 grpc_channel_args_destroy(args);
442 gpr_free(state);
443 }
444 *port_num = 0;
445
446done:
447 if (errors != nullptr) {
448 for (i = 0; i < naddrs; i++) {
449 GRPC_ERROR_UNREF(errors[i]);
450 }
451 gpr_free(errors);
452 }
453 return err;
454}
455