aboutsummaryrefslogtreecommitdiffhomepage
path: root/src/core/iomgr/tcp_server_windows.c
blob: b513d854aae183d5650701abb6ae2821d3a094f2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
/*
 *
 * Copyright 2015, Google Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#include <grpc/support/port_platform.h>

#ifdef GPR_WINSOCK_SOCKET

#define _GNU_SOURCE
#include "src/core/iomgr/sockaddr_utils.h"

#include <grpc/support/alloc.h>
#include <grpc/support/log.h>
#include <grpc/support/log_win32.h>
#include <grpc/support/string_util.h>
#include <grpc/support/sync.h>
#include <grpc/support/time.h>

#include "src/core/iomgr/iocp_windows.h"
#include "src/core/iomgr/pollset_windows.h"
#include "src/core/iomgr/socket_windows.h"
#include "src/core/iomgr/tcp_server.h"
#include "src/core/iomgr/tcp_windows.h"

#define INIT_PORT_CAP 2
#define MIN_SAFE_ACCEPT_QUEUE_SIZE 100

/* one listening port */
typedef struct server_port {
  /* This seemingly magic number comes from AcceptEx's documentation. each
     address buffer needs to have at least 16 more bytes at their end. */
  gpr_uint8 addresses[(sizeof(struct sockaddr_in6) + 16) * 2];
  /* This will hold the socket for the next accept. */
  SOCKET new_socket;
  /* The listener winsocked. */
  grpc_winsocket *socket;
  grpc_tcp_server *server;
  /* The cached AcceptEx for that port. */
  LPFN_ACCEPTEX AcceptEx;
  int shutting_down;
} server_port;

/* the overall server */
struct grpc_tcp_server {
  grpc_tcp_server_cb cb;
  void *cb_arg;

  gpr_mu mu;

  /* active port count: how many ports are actually still listening */
  int active_ports;

  /* all listening ports */
  server_port *ports;
  size_t nports;
  size_t port_capacity;

  /* shutdown callback */
  void(*shutdown_complete)(void *);
  void *shutdown_complete_arg;
};

/* Public function. Allocates the proper data structures to hold a
   grpc_tcp_server. */
grpc_tcp_server *grpc_tcp_server_create(void) {
  grpc_tcp_server *s = gpr_malloc(sizeof(grpc_tcp_server));
  gpr_mu_init(&s->mu);
  s->active_ports = 0;
  s->cb = NULL;
  s->cb_arg = NULL;
  s->ports = gpr_malloc(sizeof(server_port) * INIT_PORT_CAP);
  s->nports = 0;
  s->port_capacity = INIT_PORT_CAP;
  s->shutdown_complete = NULL;
  return s;
}

static void dont_care_about_shutdown_completion(void *arg) {}

static void finish_shutdown(grpc_tcp_server *s) {
  size_t i;

  s->shutdown_complete(s->shutdown_complete_arg);

  /* Now that the accepts have been aborted, we can destroy the sockets.
  The IOCP won't get notified on these, so we can flag them as already
  closed by the system. */
  for (i = 0; i < s->nports; i++) {
    server_port *sp = &s->ports[i];
    grpc_winsocket_destroy(sp->socket);
  }
  gpr_free(s->ports);
  gpr_free(s);
}

/* Public function. Stops and destroys a grpc_tcp_server. */
void grpc_tcp_server_destroy(grpc_tcp_server *s,
                             void (*shutdown_complete)(void *shutdown_done_arg),
                             void *shutdown_complete_arg) {
  size_t i;
  int immediately_done = 0;
  gpr_mu_lock(&s->mu);

  s->shutdown_complete = shutdown_complete
    ? shutdown_complete
    : dont_care_about_shutdown_completion;
  s->shutdown_complete_arg = shutdown_complete_arg;

  /* First, shutdown all fd's. This will queue abortion calls for all
     of the pending accepts due to the normal operation mechanism. */
  if (s->active_ports == 0) {
    immediately_done = 1;
  }
  for (i = 0; i < s->nports; i++) {
    server_port *sp = &s->ports[i];
    sp->shutting_down = 1;
    grpc_winsocket_shutdown(sp->socket);
  }
  gpr_mu_unlock(&s->mu);

  if (immediately_done) {
    finish_shutdown(s);
  }
}

/* Prepare (bind) a recently-created socket for listening. */
static int prepare_socket(SOCKET sock, const struct sockaddr *addr,
                          int addr_len) {
  struct sockaddr_storage sockname_temp;
  socklen_t sockname_len;

  if (sock == INVALID_SOCKET) goto error;

  if (!grpc_tcp_prepare_socket(sock)) {
    char *utf8_message = gpr_format_message(WSAGetLastError());
    gpr_log(GPR_ERROR, "Unable to prepare socket: %s", utf8_message);
    gpr_free(utf8_message);
    goto error;
  }

  if (bind(sock, addr, addr_len) == SOCKET_ERROR) {
    char *addr_str;
    char *utf8_message = gpr_format_message(WSAGetLastError());
    grpc_sockaddr_to_string(&addr_str, addr, 0);
    gpr_log(GPR_ERROR, "bind addr=%s: %s", addr_str, utf8_message);
    gpr_free(utf8_message);
    gpr_free(addr_str);
    goto error;
  }

  if (listen(sock, SOMAXCONN) == SOCKET_ERROR) {
    char *utf8_message = gpr_format_message(WSAGetLastError());
    gpr_log(GPR_ERROR, "listen: %s", utf8_message);
    gpr_free(utf8_message);
    goto error;
  }

  sockname_len = sizeof(sockname_temp);
  if (getsockname(sock, (struct sockaddr *)&sockname_temp, &sockname_len) ==
      SOCKET_ERROR) {
    char *utf8_message = gpr_format_message(WSAGetLastError());
    gpr_log(GPR_ERROR, "getsockname: %s", utf8_message);
    gpr_free(utf8_message);
    goto error;
  }

  return grpc_sockaddr_get_port((struct sockaddr *)&sockname_temp);

error:
  if (sock != INVALID_SOCKET) closesocket(sock);
  return -1;
}

static void decrement_active_ports_and_notify(server_port *sp) {
  int notify = 0;
  sp->shutting_down = 0;
  gpr_mu_lock(&sp->server->mu);
  GPR_ASSERT(sp->server->active_ports > 0);
  if (0 == --sp->server->active_ports && sp->server->shutdown_complete != NULL) {
    notify = 1;
  }
  gpr_mu_unlock(&sp->server->mu);
  if (notify) {
    finish_shutdown(sp->server);
  }
}

/* start_accept will reference that for the IOCP notification request. */
static void on_accept(void *arg, int from_iocp);

/* In order to do an async accept, we need to create a socket first which
   will be the one assigned to the new incoming connection. */
static void start_accept(server_port *port) {
  SOCKET sock = INVALID_SOCKET;
  char *message;
  char *utf8_message;
  BOOL success;
  DWORD addrlen = sizeof(struct sockaddr_in6) + 16;
  DWORD bytes_received = 0;

  sock = WSASocket(AF_INET6, SOCK_STREAM, IPPROTO_TCP, NULL, 0,
                   WSA_FLAG_OVERLAPPED);

  if (sock == INVALID_SOCKET) {
    message = "Unable to create socket: %s";
    goto failure;
  }

  if (!grpc_tcp_prepare_socket(sock)) {
    message = "Unable to prepare socket: %s";
    goto failure;
  }

  /* Start the "accept" asynchronously. */
  success = port->AcceptEx(port->socket->socket, sock, port->addresses, 0,
                           addrlen, addrlen, &bytes_received,
                           &port->socket->read_info.overlapped);

  /* It is possible to get an accept immediately without delay. However, we
     will still get an IOCP notification for it. So let's just ignore it. */
  if (!success) {
    int error = WSAGetLastError();
    if (error != ERROR_IO_PENDING) {
      message = "AcceptEx failed: %s";
      goto failure;
    }
  }

  /* We're ready to do the accept. Calling grpc_socket_notify_on_read may
     immediately process an accept that happened in the meantime. */
  port->new_socket = sock;
  grpc_socket_notify_on_read(port->socket, on_accept, port);
  return;

failure:
  if (port->shutting_down) {
    /* We are abandoning the listener port, take that into account to prevent
       occasional hangs on shutdown. The hang happens when sp->shutting_down
       change is not seen by on_accept and we proceed to trying new accept,
       but we fail there because the listening port has been closed in the
       meantime. */
    decrement_active_ports_and_notify(port);
    return;
  }
  utf8_message = gpr_format_message(WSAGetLastError());
  gpr_log(GPR_ERROR, message, utf8_message);
  gpr_free(utf8_message);
  if (sock != INVALID_SOCKET) closesocket(sock);
}

/* Event manager callback when reads are ready. */
static void on_accept(void *arg, int from_iocp) {
  server_port *sp = arg;
  SOCKET sock = sp->new_socket;
  grpc_winsocket_callback_info *info = &sp->socket->read_info;
  grpc_endpoint *ep = NULL;
  struct sockaddr_storage peer_name;
  char *peer_name_string;
  char *fd_name;
  int peer_name_len = sizeof(peer_name);
  DWORD transfered_bytes;
  DWORD flags;
  BOOL wsa_success;
  int err;

  /* The general mechanism for shutting down is to queue abortion calls. While
     this is necessary in the read/write case, it's useless for the accept
     case. We only need to adjust the pending callback count */
  if (!from_iocp) {
    return;
  }

  /* The IOCP notified us of a completed operation. Let's grab the results,
      and act accordingly. */
  transfered_bytes = 0;
  wsa_success = WSAGetOverlappedResult(sock, &info->overlapped,
                                       &transfered_bytes, FALSE, &flags);
  if (!wsa_success) {
    if (sp->shutting_down) {
      /* During the shutdown case, we ARE expecting an error. So that's well,
         and we can wake up the shutdown thread. */
      decrement_active_ports_and_notify(sp);
      return;
    } else {
      char *utf8_message = gpr_format_message(WSAGetLastError());
      gpr_log(GPR_ERROR, "on_accept error: %s", utf8_message);
      gpr_free(utf8_message);
      closesocket(sock);
    }
  } else {
    if (!sp->shutting_down) {
      peer_name_string = NULL;
      err = setsockopt(sock, SOL_SOCKET, SO_UPDATE_ACCEPT_CONTEXT,
                       (char *)&sp->socket->socket, sizeof(sp->socket->socket));
      if (err) {
        char *utf8_message = gpr_format_message(WSAGetLastError());
        gpr_log(GPR_ERROR, "setsockopt error: %s", utf8_message);
        gpr_free(utf8_message);
      }
      err = getpeername(sock, (struct sockaddr *)&peer_name, &peer_name_len);
      if (!err) {
        peer_name_string = grpc_sockaddr_to_uri((struct sockaddr *)&peer_name);
      } else {
        char *utf8_message = gpr_format_message(WSAGetLastError());
        gpr_log(GPR_ERROR, "getpeername error: %s", utf8_message);
        gpr_free(utf8_message);
      }
      gpr_asprintf(&fd_name, "tcp_server:%s", peer_name_string);
      ep = grpc_tcp_create(grpc_winsocket_create(sock, fd_name),
                           peer_name_string);
      gpr_free(fd_name);
      gpr_free(peer_name_string);
    }
  }

  /* The only time we should call our callback, is where we successfully
     managed to accept a connection, and created an endpoint. */
  if (ep) sp->server->cb(sp->server->cb_arg, ep);
  /* As we were notified from the IOCP of one and exactly one accept,
     the former socked we created has now either been destroy or assigned
     to the new connection. We need to create a new one for the next
     connection. */
  start_accept(sp);
}

static int add_socket_to_server(grpc_tcp_server *s, SOCKET sock,
                                const struct sockaddr *addr, int addr_len) {
  server_port *sp;
  int port;
  int status;
  GUID guid = WSAID_ACCEPTEX;
  DWORD ioctl_num_bytes;
  LPFN_ACCEPTEX AcceptEx;

  if (sock == INVALID_SOCKET) return -1;

  /* We need to grab the AcceptEx pointer for that port, as it may be
     interface-dependent. We'll cache it to avoid doing that again. */
  status =
      WSAIoctl(sock, SIO_GET_EXTENSION_FUNCTION_POINTER, &guid, sizeof(guid),
               &AcceptEx, sizeof(AcceptEx), &ioctl_num_bytes, NULL, NULL);

  if (status != 0) {
    char *utf8_message = gpr_format_message(WSAGetLastError());
    gpr_log(GPR_ERROR, "on_connect error: %s", utf8_message);
    gpr_free(utf8_message);
    closesocket(sock);
    return -1;
  }

  port = prepare_socket(sock, addr, addr_len);
  if (port >= 0) {
    gpr_mu_lock(&s->mu);
    GPR_ASSERT(!s->cb && "must add ports before starting server");
    /* append it to the list under a lock */
    if (s->nports == s->port_capacity) {
      s->port_capacity *= 2;
      s->ports = gpr_realloc(s->ports, sizeof(server_port) * s->port_capacity);
    }
    sp = &s->ports[s->nports++];
    sp->server = s;
    sp->socket = grpc_winsocket_create(sock, "listener");
    sp->shutting_down = 0;
    sp->AcceptEx = AcceptEx;
    sp->new_socket = INVALID_SOCKET;
    GPR_ASSERT(sp->socket);
    gpr_mu_unlock(&s->mu);
  }

  return port;
}

int grpc_tcp_server_add_port(grpc_tcp_server *s, const void *addr,
                             int addr_len) {
  int allocated_port = -1;
  unsigned i;
  SOCKET sock;
  struct sockaddr_in6 addr6_v4mapped;
  struct sockaddr_in6 wildcard;
  struct sockaddr *allocated_addr = NULL;
  struct sockaddr_storage sockname_temp;
  socklen_t sockname_len;
  int port;

  /* Check if this is a wildcard port, and if so, try to keep the port the same
     as some previously created listener. */
  if (grpc_sockaddr_get_port(addr) == 0) {
    for (i = 0; i < s->nports; i++) {
      sockname_len = sizeof(sockname_temp);
      if (0 == getsockname(s->ports[i].socket->socket,
                           (struct sockaddr *)&sockname_temp, &sockname_len)) {
        port = grpc_sockaddr_get_port((struct sockaddr *)&sockname_temp);
        if (port > 0) {
          allocated_addr = malloc(addr_len);
          memcpy(allocated_addr, addr, addr_len);
          grpc_sockaddr_set_port(allocated_addr, port);
          addr = allocated_addr;
          break;
        }
      }
    }
  }

  if (grpc_sockaddr_to_v4mapped(addr, &addr6_v4mapped)) {
    addr = (const struct sockaddr *)&addr6_v4mapped;
    addr_len = sizeof(addr6_v4mapped);
  }

  /* Treat :: or 0.0.0.0 as a family-agnostic wildcard. */
  if (grpc_sockaddr_is_wildcard(addr, &port)) {
    grpc_sockaddr_make_wildcard6(port, &wildcard);

    addr = (struct sockaddr *)&wildcard;
    addr_len = sizeof(wildcard);
  }

  sock = WSASocket(AF_INET6, SOCK_STREAM, IPPROTO_TCP, NULL, 0,
                   WSA_FLAG_OVERLAPPED);
  if (sock == INVALID_SOCKET) {
    char *utf8_message = gpr_format_message(WSAGetLastError());
    gpr_log(GPR_ERROR, "unable to create socket: %s", utf8_message);
    gpr_free(utf8_message);
  }

  allocated_port = add_socket_to_server(s, sock, addr, addr_len);
  gpr_free(allocated_addr);

  return allocated_port;
}

SOCKET grpc_tcp_server_get_socket(grpc_tcp_server *s, unsigned index) {
  return (index < s->nports) ? s->ports[index].socket->socket : INVALID_SOCKET;
}

void grpc_tcp_server_start(grpc_tcp_server *s, grpc_pollset **pollset,
                           size_t pollset_count, grpc_tcp_server_cb cb,
                           void *cb_arg) {
  size_t i;
  GPR_ASSERT(cb);
  gpr_mu_lock(&s->mu);
  GPR_ASSERT(!s->cb);
  GPR_ASSERT(s->active_ports == 0);
  s->cb = cb;
  s->cb_arg = cb_arg;
  for (i = 0; i < s->nports; i++) {
    start_accept(s->ports + i);
    s->active_ports++;
  }
  gpr_mu_unlock(&s->mu);
}

#endif /* GPR_WINSOCK_SOCKET */