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 <grpc/grpc.h>
24
25 #include <inttypes.h>
26 #include <limits.h>
27 #include <string.h>
28
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/tcp_server.h"
43 #include "src/core/lib/slice/slice_internal.h"
44 #include "src/core/lib/surface/api_trace.h"
45 #include "src/core/lib/surface/server.h"
46
47 typedef struct {
48 grpc_server* server;
49 grpc_tcp_server* tcp_server;
50 grpc_channel_args* args;
51 gpr_mu mu;
52 bool shutdown;
53 grpc_closure tcp_server_shutdown_complete;
54 grpc_closure* server_destroy_listener_done;
55 grpc_handshake_manager* pending_handshake_mgrs;
56 } server_state;
57
58 typedef struct {
59 gpr_refcount refs;
60 server_state* svr_state;
61 grpc_pollset* accepting_pollset;
62 grpc_tcp_server_acceptor* acceptor;
63 grpc_handshake_manager* handshake_mgr;
64 // State for enforcing handshake timeout on receiving HTTP/2 settings.
65 grpc_chttp2_transport* transport;
66 grpc_millis deadline;
67 grpc_timer timer;
68 grpc_closure on_timeout;
69 grpc_closure on_receive_settings;
70 } server_connection_state;
71
server_connection_state_unref(server_connection_state * connection_state)72 static void server_connection_state_unref(
73 server_connection_state* connection_state) {
74 if (gpr_unref(&connection_state->refs)) {
75 if (connection_state->transport != nullptr) {
76 GRPC_CHTTP2_UNREF_TRANSPORT(connection_state->transport,
77 "receive settings timeout");
78 }
79 gpr_free(connection_state);
80 }
81 }
82
on_timeout(void * arg,grpc_error * error)83 static void on_timeout(void* arg, grpc_error* error) {
84 server_connection_state* connection_state =
85 static_cast<server_connection_state*>(arg);
86 // Note that we may be called with GRPC_ERROR_NONE when the timer fires
87 // or with an error indicating that the timer system is being shut down.
88 if (error != GRPC_ERROR_CANCELLED) {
89 grpc_transport_op* op = grpc_make_transport_op(nullptr);
90 op->disconnect_with_error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
91 "Did not receive HTTP/2 settings before handshake timeout");
92 grpc_transport_perform_op(&connection_state->transport->base, op);
93 }
94 server_connection_state_unref(connection_state);
95 }
96
on_receive_settings(void * arg,grpc_error * error)97 static void on_receive_settings(void* arg, grpc_error* error) {
98 server_connection_state* connection_state =
99 static_cast<server_connection_state*>(arg);
100 if (error == GRPC_ERROR_NONE) {
101 grpc_timer_cancel(&connection_state->timer);
102 }
103 server_connection_state_unref(connection_state);
104 }
105
on_handshake_done(void * arg,grpc_error * error)106 static void on_handshake_done(void* arg, grpc_error* error) {
107 grpc_handshaker_args* args = static_cast<grpc_handshaker_args*>(arg);
108 server_connection_state* connection_state =
109 static_cast<server_connection_state*>(args->user_data);
110 gpr_mu_lock(&connection_state->svr_state->mu);
111 if (error != GRPC_ERROR_NONE || connection_state->svr_state->shutdown) {
112 const char* error_str = grpc_error_string(error);
113 gpr_log(GPR_DEBUG, "Handshaking failed: %s", error_str);
114 if (error == GRPC_ERROR_NONE && args->endpoint != nullptr) {
115 // We were shut down after handshaking completed successfully, so
116 // destroy the endpoint here.
117 // TODO(ctiller): It is currently necessary to shutdown endpoints
118 // before destroying them, even if we know that there are no
119 // pending read/write callbacks. This should be fixed, at which
120 // point this can be removed.
121 grpc_endpoint_shutdown(args->endpoint, GRPC_ERROR_NONE);
122 grpc_endpoint_destroy(args->endpoint);
123 grpc_channel_args_destroy(args->args);
124 grpc_slice_buffer_destroy_internal(args->read_buffer);
125 gpr_free(args->read_buffer);
126 }
127 } else {
128 // If the handshaking succeeded but there is no endpoint, then the
129 // handshaker may have handed off the connection to some external
130 // code, so we can just clean up here without creating a transport.
131 if (args->endpoint != nullptr) {
132 grpc_transport* transport =
133 grpc_create_chttp2_transport(args->args, args->endpoint, false);
134 grpc_server_setup_transport(
135 connection_state->svr_state->server, transport,
136 connection_state->accepting_pollset, args->args);
137 // Use notify_on_receive_settings callback to enforce the
138 // handshake deadline.
139 connection_state->transport =
140 reinterpret_cast<grpc_chttp2_transport*>(transport);
141 gpr_ref(&connection_state->refs);
142 GRPC_CLOSURE_INIT(&connection_state->on_receive_settings,
143 on_receive_settings, connection_state,
144 grpc_schedule_on_exec_ctx);
145 grpc_chttp2_transport_start_reading(
146 transport, args->read_buffer, &connection_state->on_receive_settings);
147 grpc_channel_args_destroy(args->args);
148 gpr_ref(&connection_state->refs);
149 GRPC_CHTTP2_REF_TRANSPORT((grpc_chttp2_transport*)transport,
150 "receive settings timeout");
151 GRPC_CLOSURE_INIT(&connection_state->on_timeout, on_timeout,
152 connection_state, grpc_schedule_on_exec_ctx);
153 grpc_timer_init(&connection_state->timer, connection_state->deadline,
154 &connection_state->on_timeout);
155 }
156 }
157 grpc_handshake_manager_pending_list_remove(
158 &connection_state->svr_state->pending_handshake_mgrs,
159 connection_state->handshake_mgr);
160 gpr_mu_unlock(&connection_state->svr_state->mu);
161 grpc_handshake_manager_destroy(connection_state->handshake_mgr);
162 gpr_free(connection_state->acceptor);
163 grpc_tcp_server_unref(connection_state->svr_state->tcp_server);
164 server_connection_state_unref(connection_state);
165 }
166
on_accept(void * arg,grpc_endpoint * tcp,grpc_pollset * accepting_pollset,grpc_tcp_server_acceptor * acceptor)167 static void on_accept(void* arg, grpc_endpoint* tcp,
168 grpc_pollset* accepting_pollset,
169 grpc_tcp_server_acceptor* acceptor) {
170 server_state* state = static_cast<server_state*>(arg);
171 gpr_mu_lock(&state->mu);
172 if (state->shutdown) {
173 gpr_mu_unlock(&state->mu);
174 grpc_endpoint_shutdown(tcp, GRPC_ERROR_NONE);
175 grpc_endpoint_destroy(tcp);
176 gpr_free(acceptor);
177 return;
178 }
179 grpc_handshake_manager* handshake_mgr = grpc_handshake_manager_create();
180 grpc_handshake_manager_pending_list_add(&state->pending_handshake_mgrs,
181 handshake_mgr);
182 grpc_tcp_server_ref(state->tcp_server);
183 gpr_mu_unlock(&state->mu);
184 server_connection_state* connection_state =
185 static_cast<server_connection_state*>(
186 gpr_zalloc(sizeof(*connection_state)));
187 gpr_ref_init(&connection_state->refs, 1);
188 connection_state->svr_state = state;
189 connection_state->accepting_pollset = accepting_pollset;
190 connection_state->acceptor = acceptor;
191 connection_state->handshake_mgr = handshake_mgr;
192 grpc_handshakers_add(HANDSHAKER_SERVER, state->args,
193 connection_state->handshake_mgr);
194 const grpc_arg* timeout_arg =
195 grpc_channel_args_find(state->args, GRPC_ARG_SERVER_HANDSHAKE_TIMEOUT_MS);
196 connection_state->deadline =
197 grpc_core::ExecCtx::Get()->Now() +
198 grpc_channel_arg_get_integer(timeout_arg,
199 {120 * GPR_MS_PER_SEC, 1, INT_MAX});
200 grpc_handshake_manager_do_handshake(
201 connection_state->handshake_mgr, nullptr /* interested_parties */, tcp,
202 state->args, connection_state->deadline, acceptor, on_handshake_done,
203 connection_state);
204 }
205
206 /* Server callback: start listening on our ports */
server_start_listener(grpc_server * server,void * arg,grpc_pollset ** pollsets,size_t pollset_count)207 static void server_start_listener(grpc_server* server, void* arg,
208 grpc_pollset** pollsets,
209 size_t pollset_count) {
210 server_state* state = static_cast<server_state*>(arg);
211 gpr_mu_lock(&state->mu);
212 state->shutdown = false;
213 gpr_mu_unlock(&state->mu);
214 grpc_tcp_server_start(state->tcp_server, pollsets, pollset_count, on_accept,
215 state);
216 }
217
tcp_server_shutdown_complete(void * arg,grpc_error * error)218 static void tcp_server_shutdown_complete(void* arg, grpc_error* error) {
219 server_state* state = static_cast<server_state*>(arg);
220 /* ensure all threads have unlocked */
221 gpr_mu_lock(&state->mu);
222 grpc_closure* destroy_done = state->server_destroy_listener_done;
223 GPR_ASSERT(state->shutdown);
224 grpc_handshake_manager_pending_list_shutdown_all(
225 state->pending_handshake_mgrs, GRPC_ERROR_REF(error));
226 gpr_mu_unlock(&state->mu);
227 // Flush queued work before destroying handshaker factory, since that
228 // may do a synchronous unref.
229 grpc_core::ExecCtx::Get()->Flush();
230 if (destroy_done != nullptr) {
231 destroy_done->cb(destroy_done->cb_arg, GRPC_ERROR_REF(error));
232 grpc_core::ExecCtx::Get()->Flush();
233 }
234 grpc_channel_args_destroy(state->args);
235 gpr_mu_destroy(&state->mu);
236 gpr_free(state);
237 }
238
239 /* Server callback: destroy the tcp listener (so we don't generate further
240 callbacks) */
server_destroy_listener(grpc_server * server,void * arg,grpc_closure * destroy_done)241 static void server_destroy_listener(grpc_server* server, void* arg,
242 grpc_closure* destroy_done) {
243 server_state* state = static_cast<server_state*>(arg);
244 gpr_mu_lock(&state->mu);
245 state->shutdown = true;
246 state->server_destroy_listener_done = destroy_done;
247 grpc_tcp_server* tcp_server = state->tcp_server;
248 gpr_mu_unlock(&state->mu);
249 grpc_tcp_server_shutdown_listeners(tcp_server);
250 grpc_tcp_server_unref(tcp_server);
251 }
252
grpc_chttp2_server_add_port(grpc_server * server,const char * addr,grpc_channel_args * args,int * port_num)253 grpc_error* grpc_chttp2_server_add_port(grpc_server* server, const char* addr,
254 grpc_channel_args* args,
255 int* port_num) {
256 grpc_resolved_addresses* resolved = nullptr;
257 grpc_tcp_server* tcp_server = nullptr;
258 size_t i;
259 size_t count = 0;
260 int port_temp;
261 grpc_error* err = GRPC_ERROR_NONE;
262 server_state* state = nullptr;
263 grpc_error** errors = nullptr;
264 size_t naddrs = 0;
265
266 *port_num = -1;
267
268 /* resolve address */
269 err = grpc_blocking_resolve_address(addr, "https", &resolved);
270 if (err != GRPC_ERROR_NONE) {
271 goto error;
272 }
273 state = static_cast<server_state*>(gpr_zalloc(sizeof(*state)));
274 GRPC_CLOSURE_INIT(&state->tcp_server_shutdown_complete,
275 tcp_server_shutdown_complete, state,
276 grpc_schedule_on_exec_ctx);
277 err = grpc_tcp_server_create(&state->tcp_server_shutdown_complete, args,
278 &tcp_server);
279 if (err != GRPC_ERROR_NONE) {
280 goto error;
281 }
282
283 state->server = server;
284 state->tcp_server = tcp_server;
285 state->args = args;
286 state->shutdown = true;
287 gpr_mu_init(&state->mu);
288
289 naddrs = resolved->naddrs;
290 errors = static_cast<grpc_error**>(gpr_malloc(sizeof(*errors) * naddrs));
291 for (i = 0; i < naddrs; i++) {
292 errors[i] =
293 grpc_tcp_server_add_port(tcp_server, &resolved->addrs[i], &port_temp);
294 if (errors[i] == GRPC_ERROR_NONE) {
295 if (*port_num == -1) {
296 *port_num = port_temp;
297 } else {
298 GPR_ASSERT(*port_num == port_temp);
299 }
300 count++;
301 }
302 }
303 if (count == 0) {
304 char* msg;
305 gpr_asprintf(&msg, "No address added out of total %" PRIuPTR " resolved",
306 naddrs);
307 err = GRPC_ERROR_CREATE_REFERENCING_FROM_COPIED_STRING(msg, errors, naddrs);
308 gpr_free(msg);
309 goto error;
310 } else if (count != naddrs) {
311 char* msg;
312 gpr_asprintf(&msg,
313 "Only %" PRIuPTR " addresses added out of total %" PRIuPTR
314 " resolved",
315 count, naddrs);
316 err = GRPC_ERROR_CREATE_REFERENCING_FROM_COPIED_STRING(msg, errors, naddrs);
317 gpr_free(msg);
318
319 const char* warning_message = grpc_error_string(err);
320 gpr_log(GPR_INFO, "WARNING: %s", warning_message);
321
322 /* we managed to bind some addresses: continue */
323 }
324 grpc_resolved_addresses_destroy(resolved);
325
326 /* Register with the server only upon success */
327 grpc_server_add_listener(server, state, server_start_listener,
328 server_destroy_listener);
329 goto done;
330
331 /* Error path: cleanup and return */
332 error:
333 GPR_ASSERT(err != GRPC_ERROR_NONE);
334 if (resolved) {
335 grpc_resolved_addresses_destroy(resolved);
336 }
337 if (tcp_server) {
338 grpc_tcp_server_unref(tcp_server);
339 } else {
340 grpc_channel_args_destroy(args);
341 gpr_free(state);
342 }
343 *port_num = 0;
344
345 done:
346 if (errors != nullptr) {
347 for (i = 0; i < naddrs; i++) {
348 GRPC_ERROR_UNREF(errors[i]);
349 }
350 gpr_free(errors);
351 }
352 return err;
353 }
354