io: remove checking of EWOULDBLOCK
[sdk/emulator/qemu.git] / io / channel-socket.c
1 /*
2  * QEMU I/O channels sockets driver
3  *
4  * Copyright (c) 2015 Red Hat, Inc.
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18  *
19  */
20
21 #include "qemu/osdep.h"
22 #include "io/channel-socket.h"
23 #include "io/channel-watch.h"
24 #include "trace.h"
25
26 #define SOCKET_MAX_FDS 16
27
28 SocketAddress *
29 qio_channel_socket_get_local_address(QIOChannelSocket *ioc,
30                                      Error **errp)
31 {
32     return socket_sockaddr_to_address(&ioc->localAddr,
33                                       ioc->localAddrLen,
34                                       errp);
35 }
36
37 SocketAddress *
38 qio_channel_socket_get_remote_address(QIOChannelSocket *ioc,
39                                       Error **errp)
40 {
41     return socket_sockaddr_to_address(&ioc->remoteAddr,
42                                       ioc->remoteAddrLen,
43                                       errp);
44 }
45
46 QIOChannelSocket *
47 qio_channel_socket_new(void)
48 {
49     QIOChannelSocket *sioc;
50     QIOChannel *ioc;
51
52     sioc = QIO_CHANNEL_SOCKET(object_new(TYPE_QIO_CHANNEL_SOCKET));
53     sioc->fd = -1;
54
55     ioc = QIO_CHANNEL(sioc);
56     ioc->features |= (1 << QIO_CHANNEL_FEATURE_SHUTDOWN);
57
58     trace_qio_channel_socket_new(sioc);
59
60     return sioc;
61 }
62
63
64 static int
65 qio_channel_socket_set_fd(QIOChannelSocket *sioc,
66                           int fd,
67                           Error **errp)
68 {
69     if (sioc->fd != -1) {
70         error_setg(errp, "Socket is already open");
71         return -1;
72     }
73
74     sioc->fd = fd;
75     sioc->remoteAddrLen = sizeof(sioc->remoteAddr);
76     sioc->localAddrLen = sizeof(sioc->localAddr);
77
78
79     if (getpeername(fd, (struct sockaddr *)&sioc->remoteAddr,
80                     &sioc->remoteAddrLen) < 0) {
81         if (socket_error() == ENOTCONN) {
82             memset(&sioc->remoteAddr, 0, sizeof(sioc->remoteAddr));
83             sioc->remoteAddrLen = sizeof(sioc->remoteAddr);
84         } else {
85             error_setg_errno(errp, socket_error(),
86                              "Unable to query remote socket address");
87             goto error;
88         }
89     }
90
91     if (getsockname(fd, (struct sockaddr *)&sioc->localAddr,
92                     &sioc->localAddrLen) < 0) {
93         error_setg_errno(errp, socket_error(),
94                          "Unable to query local socket address");
95         goto error;
96     }
97
98 #ifndef WIN32
99     if (sioc->localAddr.ss_family == AF_UNIX) {
100         QIOChannel *ioc = QIO_CHANNEL(sioc);
101         ioc->features |= (1 << QIO_CHANNEL_FEATURE_FD_PASS);
102     }
103 #endif /* WIN32 */
104
105     return 0;
106
107  error:
108     sioc->fd = -1; /* Let the caller close FD on failure */
109     return -1;
110 }
111
112 QIOChannelSocket *
113 qio_channel_socket_new_fd(int fd,
114                           Error **errp)
115 {
116     QIOChannelSocket *ioc;
117
118     ioc = qio_channel_socket_new();
119     if (qio_channel_socket_set_fd(ioc, fd, errp) < 0) {
120         object_unref(OBJECT(ioc));
121         return NULL;
122     }
123
124     trace_qio_channel_socket_new_fd(ioc, fd);
125
126     return ioc;
127 }
128
129
130 int qio_channel_socket_connect_sync(QIOChannelSocket *ioc,
131                                     SocketAddress *addr,
132                                     Error **errp)
133 {
134     int fd;
135
136     trace_qio_channel_socket_connect_sync(ioc, addr);
137     fd = socket_connect(addr, errp, NULL, NULL);
138     if (fd < 0) {
139         trace_qio_channel_socket_connect_fail(ioc);
140         return -1;
141     }
142
143     trace_qio_channel_socket_connect_complete(ioc, fd);
144     if (qio_channel_socket_set_fd(ioc, fd, errp) < 0) {
145         close(fd);
146         return -1;
147     }
148
149     return 0;
150 }
151
152
153 static int qio_channel_socket_connect_worker(QIOTask *task,
154                                              Error **errp,
155                                              gpointer opaque)
156 {
157     QIOChannelSocket *ioc = QIO_CHANNEL_SOCKET(qio_task_get_source(task));
158     SocketAddress *addr = opaque;
159     int ret;
160
161     ret = qio_channel_socket_connect_sync(ioc,
162                                           addr,
163                                           errp);
164
165     object_unref(OBJECT(ioc));
166     return ret;
167 }
168
169
170 void qio_channel_socket_connect_async(QIOChannelSocket *ioc,
171                                       SocketAddress *addr,
172                                       QIOTaskFunc callback,
173                                       gpointer opaque,
174                                       GDestroyNotify destroy)
175 {
176     QIOTask *task = qio_task_new(
177         OBJECT(ioc), callback, opaque, destroy);
178     SocketAddress *addrCopy;
179
180     qapi_copy_SocketAddress(&addrCopy, addr);
181
182     /* socket_connect() does a non-blocking connect(), but it
183      * still blocks in DNS lookups, so we must use a thread */
184     trace_qio_channel_socket_connect_async(ioc, addr);
185     qio_task_run_in_thread(task,
186                            qio_channel_socket_connect_worker,
187                            addrCopy,
188                            (GDestroyNotify)qapi_free_SocketAddress);
189 }
190
191
192 int qio_channel_socket_listen_sync(QIOChannelSocket *ioc,
193                                    SocketAddress *addr,
194                                    Error **errp)
195 {
196     int fd;
197
198     trace_qio_channel_socket_listen_sync(ioc, addr);
199     fd = socket_listen(addr, errp);
200     if (fd < 0) {
201         trace_qio_channel_socket_listen_fail(ioc);
202         return -1;
203     }
204
205     trace_qio_channel_socket_listen_complete(ioc, fd);
206     if (qio_channel_socket_set_fd(ioc, fd, errp) < 0) {
207         close(fd);
208         return -1;
209     }
210
211     return 0;
212 }
213
214
215 static int qio_channel_socket_listen_worker(QIOTask *task,
216                                             Error **errp,
217                                             gpointer opaque)
218 {
219     QIOChannelSocket *ioc = QIO_CHANNEL_SOCKET(qio_task_get_source(task));
220     SocketAddress *addr = opaque;
221     int ret;
222
223     ret = qio_channel_socket_listen_sync(ioc,
224                                          addr,
225                                          errp);
226
227     object_unref(OBJECT(ioc));
228     return ret;
229 }
230
231
232 void qio_channel_socket_listen_async(QIOChannelSocket *ioc,
233                                      SocketAddress *addr,
234                                      QIOTaskFunc callback,
235                                      gpointer opaque,
236                                      GDestroyNotify destroy)
237 {
238     QIOTask *task = qio_task_new(
239         OBJECT(ioc), callback, opaque, destroy);
240     SocketAddress *addrCopy;
241
242     qapi_copy_SocketAddress(&addrCopy, addr);
243
244     /* socket_listen() blocks in DNS lookups, so we must use a thread */
245     trace_qio_channel_socket_listen_async(ioc, addr);
246     qio_task_run_in_thread(task,
247                            qio_channel_socket_listen_worker,
248                            addrCopy,
249                            (GDestroyNotify)qapi_free_SocketAddress);
250 }
251
252
253 int qio_channel_socket_dgram_sync(QIOChannelSocket *ioc,
254                                   SocketAddress *localAddr,
255                                   SocketAddress *remoteAddr,
256                                   Error **errp)
257 {
258     int fd;
259
260     trace_qio_channel_socket_dgram_sync(ioc, localAddr, remoteAddr);
261     fd = socket_dgram(remoteAddr, localAddr, errp);
262     if (fd < 0) {
263         trace_qio_channel_socket_dgram_fail(ioc);
264         return -1;
265     }
266
267     trace_qio_channel_socket_dgram_complete(ioc, fd);
268     if (qio_channel_socket_set_fd(ioc, fd, errp) < 0) {
269         close(fd);
270         return -1;
271     }
272
273     return 0;
274 }
275
276
277 struct QIOChannelSocketDGramWorkerData {
278     SocketAddress *localAddr;
279     SocketAddress *remoteAddr;
280 };
281
282
283 static void qio_channel_socket_dgram_worker_free(gpointer opaque)
284 {
285     struct QIOChannelSocketDGramWorkerData *data = opaque;
286     qapi_free_SocketAddress(data->localAddr);
287     qapi_free_SocketAddress(data->remoteAddr);
288     g_free(data);
289 }
290
291 static int qio_channel_socket_dgram_worker(QIOTask *task,
292                                            Error **errp,
293                                            gpointer opaque)
294 {
295     QIOChannelSocket *ioc = QIO_CHANNEL_SOCKET(qio_task_get_source(task));
296     struct QIOChannelSocketDGramWorkerData *data = opaque;
297     int ret;
298
299     /* socket_dgram() blocks in DNS lookups, so we must use a thread */
300     ret = qio_channel_socket_dgram_sync(ioc,
301                                         data->localAddr,
302                                         data->remoteAddr,
303                                         errp);
304
305     object_unref(OBJECT(ioc));
306     return ret;
307 }
308
309
310 void qio_channel_socket_dgram_async(QIOChannelSocket *ioc,
311                                     SocketAddress *localAddr,
312                                     SocketAddress *remoteAddr,
313                                     QIOTaskFunc callback,
314                                     gpointer opaque,
315                                     GDestroyNotify destroy)
316 {
317     QIOTask *task = qio_task_new(
318         OBJECT(ioc), callback, opaque, destroy);
319     struct QIOChannelSocketDGramWorkerData *data = g_new0(
320         struct QIOChannelSocketDGramWorkerData, 1);
321
322     qapi_copy_SocketAddress(&data->localAddr, localAddr);
323     qapi_copy_SocketAddress(&data->remoteAddr, remoteAddr);
324
325     trace_qio_channel_socket_dgram_async(ioc, localAddr, remoteAddr);
326     qio_task_run_in_thread(task,
327                            qio_channel_socket_dgram_worker,
328                            data,
329                            qio_channel_socket_dgram_worker_free);
330 }
331
332
333 QIOChannelSocket *
334 qio_channel_socket_accept(QIOChannelSocket *ioc,
335                           Error **errp)
336 {
337     QIOChannelSocket *cioc;
338
339     cioc = QIO_CHANNEL_SOCKET(object_new(TYPE_QIO_CHANNEL_SOCKET));
340     cioc->fd = -1;
341     cioc->remoteAddrLen = sizeof(ioc->remoteAddr);
342     cioc->localAddrLen = sizeof(ioc->localAddr);
343
344  retry:
345     trace_qio_channel_socket_accept(ioc);
346     cioc->fd = qemu_accept(ioc->fd, (struct sockaddr *)&cioc->remoteAddr,
347                            &cioc->remoteAddrLen);
348     if (cioc->fd < 0) {
349         trace_qio_channel_socket_accept_fail(ioc);
350         if (socket_error() == EINTR) {
351             goto retry;
352         }
353         goto error;
354     }
355
356     if (getsockname(cioc->fd, (struct sockaddr *)&cioc->localAddr,
357                     &cioc->localAddrLen) < 0) {
358         error_setg_errno(errp, socket_error(),
359                          "Unable to query local socket address");
360         goto error;
361     }
362
363 #ifndef WIN32
364     if (cioc->localAddr.ss_family == AF_UNIX) {
365         QIO_CHANNEL(cioc)->features |= (1 << QIO_CHANNEL_FEATURE_FD_PASS);
366     }
367 #endif /* WIN32 */
368
369     trace_qio_channel_socket_accept_complete(ioc, cioc, cioc->fd);
370     return cioc;
371
372  error:
373     object_unref(OBJECT(cioc));
374     return NULL;
375 }
376
377 static void qio_channel_socket_init(Object *obj)
378 {
379     QIOChannelSocket *ioc = QIO_CHANNEL_SOCKET(obj);
380     ioc->fd = -1;
381 }
382
383 static void qio_channel_socket_finalize(Object *obj)
384 {
385     QIOChannelSocket *ioc = QIO_CHANNEL_SOCKET(obj);
386     if (ioc->fd != -1) {
387         close(ioc->fd);
388         ioc->fd = -1;
389     }
390 }
391
392
393 #ifndef WIN32
394 static void qio_channel_socket_copy_fds(struct msghdr *msg,
395                                         int **fds, size_t *nfds)
396 {
397     struct cmsghdr *cmsg;
398
399     *nfds = 0;
400     *fds = NULL;
401
402     for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
403         int fd_size, i;
404         int gotfds;
405
406         if (cmsg->cmsg_len < CMSG_LEN(sizeof(int)) ||
407             cmsg->cmsg_level != SOL_SOCKET ||
408             cmsg->cmsg_type != SCM_RIGHTS) {
409             continue;
410         }
411
412         fd_size = cmsg->cmsg_len - CMSG_LEN(0);
413
414         if (!fd_size) {
415             continue;
416         }
417
418         gotfds = fd_size / sizeof(int);
419         *fds = g_renew(int, *fds, *nfds + gotfds);
420         memcpy(*fds + *nfds, CMSG_DATA(cmsg), fd_size);
421
422         for (i = 0; i < gotfds; i++) {
423             int fd = (*fds)[*nfds + i];
424             if (fd < 0) {
425                 continue;
426             }
427
428             /* O_NONBLOCK is preserved across SCM_RIGHTS so reset it */
429             qemu_set_block(fd);
430
431 #ifndef MSG_CMSG_CLOEXEC
432             qemu_set_cloexec(fd);
433 #endif
434         }
435         *nfds += gotfds;
436     }
437 }
438
439
440 static ssize_t qio_channel_socket_readv(QIOChannel *ioc,
441                                         const struct iovec *iov,
442                                         size_t niov,
443                                         int **fds,
444                                         size_t *nfds,
445                                         Error **errp)
446 {
447     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
448     ssize_t ret;
449     struct msghdr msg = { NULL, };
450     char control[CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS)];
451     int sflags = 0;
452
453     memset(control, 0, CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS));
454
455 #ifdef MSG_CMSG_CLOEXEC
456     sflags |= MSG_CMSG_CLOEXEC;
457 #endif
458
459     msg.msg_iov = (struct iovec *)iov;
460     msg.msg_iovlen = niov;
461     if (fds && nfds) {
462         msg.msg_control = control;
463         msg.msg_controllen = sizeof(control);
464     }
465
466  retry:
467     ret = recvmsg(sioc->fd, &msg, sflags);
468     if (ret < 0) {
469         if (socket_error() == EAGAIN) {
470             return QIO_CHANNEL_ERR_BLOCK;
471         }
472         if (socket_error() == EINTR) {
473             goto retry;
474         }
475
476         error_setg_errno(errp, socket_error(),
477                          "Unable to read from socket");
478         return -1;
479     }
480
481     if (fds && nfds) {
482         qio_channel_socket_copy_fds(&msg, fds, nfds);
483     }
484
485     return ret;
486 }
487
488 static ssize_t qio_channel_socket_writev(QIOChannel *ioc,
489                                          const struct iovec *iov,
490                                          size_t niov,
491                                          int *fds,
492                                          size_t nfds,
493                                          Error **errp)
494 {
495     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
496     ssize_t ret;
497     struct msghdr msg = { NULL, };
498     char control[CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS)];
499     size_t fdsize = sizeof(int) * nfds;
500     struct cmsghdr *cmsg;
501
502     memset(control, 0, CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS));
503
504     msg.msg_iov = (struct iovec *)iov;
505     msg.msg_iovlen = niov;
506
507     if (nfds) {
508         if (nfds > SOCKET_MAX_FDS) {
509             error_setg_errno(errp, EINVAL,
510                              "Only %d FDs can be sent, got %zu",
511                              SOCKET_MAX_FDS, nfds);
512             return -1;
513         }
514
515         msg.msg_control = control;
516         msg.msg_controllen = CMSG_SPACE(sizeof(int) * nfds);
517
518         cmsg = CMSG_FIRSTHDR(&msg);
519         cmsg->cmsg_len = CMSG_LEN(fdsize);
520         cmsg->cmsg_level = SOL_SOCKET;
521         cmsg->cmsg_type = SCM_RIGHTS;
522         memcpy(CMSG_DATA(cmsg), fds, fdsize);
523     }
524
525  retry:
526     ret = sendmsg(sioc->fd, &msg, 0);
527     if (ret <= 0) {
528         if (socket_error() == EAGAIN) {
529             return QIO_CHANNEL_ERR_BLOCK;
530         }
531         if (socket_error() == EINTR) {
532             goto retry;
533         }
534         error_setg_errno(errp, socket_error(),
535                          "Unable to write to socket");
536         return -1;
537     }
538     return ret;
539 }
540 #else /* WIN32 */
541 static ssize_t qio_channel_socket_readv(QIOChannel *ioc,
542                                         const struct iovec *iov,
543                                         size_t niov,
544                                         int **fds,
545                                         size_t *nfds,
546                                         Error **errp)
547 {
548     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
549     ssize_t done = 0;
550     ssize_t i;
551
552     for (i = 0; i < niov; i++) {
553         ssize_t ret;
554     retry:
555         ret = recv(sioc->fd,
556                    iov[i].iov_base,
557                    iov[i].iov_len,
558                    0);
559         if (ret < 0) {
560             if (socket_error() == EAGAIN) {
561                 if (done) {
562                     return done;
563                 } else {
564                     return QIO_CHANNEL_ERR_BLOCK;
565                 }
566             } else if (socket_error() == EINTR) {
567                 goto retry;
568             } else {
569                 error_setg_errno(errp, socket_error(),
570                                  "Unable to read from socket");
571                 return -1;
572             }
573         }
574         done += ret;
575         if (ret < iov[i].iov_len) {
576             return done;
577         }
578     }
579
580     return done;
581 }
582
583 static ssize_t qio_channel_socket_writev(QIOChannel *ioc,
584                                          const struct iovec *iov,
585                                          size_t niov,
586                                          int *fds,
587                                          size_t nfds,
588                                          Error **errp)
589 {
590     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
591     ssize_t done = 0;
592     ssize_t i;
593
594     for (i = 0; i < niov; i++) {
595         ssize_t ret;
596     retry:
597         ret = send(sioc->fd,
598                    iov[i].iov_base,
599                    iov[i].iov_len,
600                    0);
601         if (ret < 0) {
602             if (socket_error() == EAGAIN) {
603                 if (done) {
604                     return done;
605                 } else {
606                     return QIO_CHANNEL_ERR_BLOCK;
607                 }
608             } else if (socket_error() == EINTR) {
609                 goto retry;
610             } else {
611                 error_setg_errno(errp, socket_error(),
612                                  "Unable to write to socket");
613                 return -1;
614             }
615         }
616         done += ret;
617         if (ret < iov[i].iov_len) {
618             return done;
619         }
620     }
621
622     return done;
623 }
624 #endif /* WIN32 */
625
626 static int
627 qio_channel_socket_set_blocking(QIOChannel *ioc,
628                                 bool enabled,
629                                 Error **errp)
630 {
631     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
632
633     if (enabled) {
634         qemu_set_block(sioc->fd);
635     } else {
636         qemu_set_nonblock(sioc->fd);
637     }
638     return 0;
639 }
640
641
642 static void
643 qio_channel_socket_set_delay(QIOChannel *ioc,
644                              bool enabled)
645 {
646     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
647     int v = enabled ? 0 : 1;
648
649     qemu_setsockopt(sioc->fd,
650                     IPPROTO_TCP, TCP_NODELAY,
651                     &v, sizeof(v));
652 }
653
654
655 static void
656 qio_channel_socket_set_cork(QIOChannel *ioc,
657                             bool enabled)
658 {
659     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
660     int v = enabled ? 1 : 0;
661
662     socket_set_cork(sioc->fd, v);
663 }
664
665
666 static int
667 qio_channel_socket_close(QIOChannel *ioc,
668                          Error **errp)
669 {
670     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
671
672     if (closesocket(sioc->fd) < 0) {
673         sioc->fd = -1;
674         error_setg_errno(errp, socket_error(),
675                          "Unable to close socket");
676         return -1;
677     }
678     sioc->fd = -1;
679     return 0;
680 }
681
682 static int
683 qio_channel_socket_shutdown(QIOChannel *ioc,
684                             QIOChannelShutdown how,
685                             Error **errp)
686 {
687     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
688     int sockhow;
689
690     switch (how) {
691     case QIO_CHANNEL_SHUTDOWN_READ:
692         sockhow = SHUT_RD;
693         break;
694     case QIO_CHANNEL_SHUTDOWN_WRITE:
695         sockhow = SHUT_WR;
696         break;
697     case QIO_CHANNEL_SHUTDOWN_BOTH:
698     default:
699         sockhow = SHUT_RDWR;
700         break;
701     }
702
703     if (shutdown(sioc->fd, sockhow) < 0) {
704         error_setg_errno(errp, socket_error(),
705                          "Unable to shutdown socket");
706         return -1;
707     }
708     return 0;
709 }
710
711 static GSource *qio_channel_socket_create_watch(QIOChannel *ioc,
712                                                 GIOCondition condition)
713 {
714     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
715     return qio_channel_create_socket_watch(ioc,
716                                            sioc->fd,
717                                            condition);
718 }
719
720 static void qio_channel_socket_class_init(ObjectClass *klass,
721                                           void *class_data G_GNUC_UNUSED)
722 {
723     QIOChannelClass *ioc_klass = QIO_CHANNEL_CLASS(klass);
724
725     ioc_klass->io_writev = qio_channel_socket_writev;
726     ioc_klass->io_readv = qio_channel_socket_readv;
727     ioc_klass->io_set_blocking = qio_channel_socket_set_blocking;
728     ioc_klass->io_close = qio_channel_socket_close;
729     ioc_klass->io_shutdown = qio_channel_socket_shutdown;
730     ioc_klass->io_set_cork = qio_channel_socket_set_cork;
731     ioc_klass->io_set_delay = qio_channel_socket_set_delay;
732     ioc_klass->io_create_watch = qio_channel_socket_create_watch;
733 }
734
735 static const TypeInfo qio_channel_socket_info = {
736     .parent = TYPE_QIO_CHANNEL,
737     .name = TYPE_QIO_CHANNEL_SOCKET,
738     .instance_size = sizeof(QIOChannelSocket),
739     .instance_init = qio_channel_socket_init,
740     .instance_finalize = qio_channel_socket_finalize,
741     .class_init = qio_channel_socket_class_init,
742 };
743
744 static void qio_channel_socket_register_types(void)
745 {
746     type_register_static(&qio_channel_socket_info);
747 }
748
749 type_init(qio_channel_socket_register_types);