xref: /openbmc/qemu/io/channel-socket.c (revision ac1d8878) 
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 "io/channel-socket.h"
22 #include "io/channel-watch.h"
23 #include "trace.h"
24 
25 #define SOCKET_MAX_FDS 16
26 
27 SocketAddress *
28 qio_channel_socket_get_local_address(QIOChannelSocket *ioc,
29                                      Error **errp)
30 {
31     return socket_sockaddr_to_address(&ioc->localAddr,
32                                       ioc->localAddrLen,
33                                       errp);
34 }
35 
36 SocketAddress *
37 qio_channel_socket_get_remote_address(QIOChannelSocket *ioc,
38                                       Error **errp)
39 {
40     return socket_sockaddr_to_address(&ioc->remoteAddr,
41                                       ioc->remoteAddrLen,
42                                       errp);
43 }
44 
45 QIOChannelSocket *
46 qio_channel_socket_new(void)
47 {
48     QIOChannelSocket *sioc;
49     QIOChannel *ioc;
50 
51     sioc = QIO_CHANNEL_SOCKET(object_new(TYPE_QIO_CHANNEL_SOCKET));
52     sioc->fd = -1;
53 
54     ioc = QIO_CHANNEL(sioc);
55     ioc->features |= (1 << QIO_CHANNEL_FEATURE_SHUTDOWN);
56 
57     trace_qio_channel_socket_new(sioc);
58 
59     return sioc;
60 }
61 
62 
63 static int
64 qio_channel_socket_set_fd(QIOChannelSocket *sioc,
65                           int fd,
66                           Error **errp)
67 {
68     if (sioc->fd != -1) {
69         error_setg(errp, "Socket is already open");
70         return -1;
71     }
72 
73     sioc->fd = fd;
74     sioc->remoteAddrLen = sizeof(sioc->remoteAddr);
75     sioc->localAddrLen = sizeof(sioc->localAddr);
76 
77 
78     if (getpeername(fd, (struct sockaddr *)&sioc->remoteAddr,
79                     &sioc->remoteAddrLen) < 0) {
80         if (socket_error() == ENOTCONN) {
81             memset(&sioc->remoteAddr, 0, sizeof(sioc->remoteAddr));
82             sioc->remoteAddrLen = sizeof(sioc->remoteAddr);
83         } else {
84             error_setg_errno(errp, socket_error(),
85                              "Unable to query remote socket address");
86             goto error;
87         }
88     }
89 
90     if (getsockname(fd, (struct sockaddr *)&sioc->localAddr,
91                     &sioc->localAddrLen) < 0) {
92         error_setg_errno(errp, socket_error(),
93                          "Unable to query local socket address");
94         goto error;
95     }
96 
97 #ifndef WIN32
98     if (sioc->localAddr.ss_family == AF_UNIX) {
99         QIOChannel *ioc = QIO_CHANNEL(sioc);
100         ioc->features |= (1 << QIO_CHANNEL_FEATURE_FD_PASS);
101     }
102 #endif /* WIN32 */
103 
104     return 0;
105 
106  error:
107     sioc->fd = -1; /* Let the caller close FD on failure */
108     return -1;
109 }
110 
111 QIOChannelSocket *
112 qio_channel_socket_new_fd(int fd,
113                           Error **errp)
114 {
115     QIOChannelSocket *ioc;
116 
117     ioc = qio_channel_socket_new();
118     if (qio_channel_socket_set_fd(ioc, fd, errp) < 0) {
119         object_unref(OBJECT(ioc));
120         return NULL;
121     }
122 
123     trace_qio_channel_socket_new_fd(ioc, fd);
124 
125     return ioc;
126 }
127 
128 
129 int qio_channel_socket_connect_sync(QIOChannelSocket *ioc,
130                                     SocketAddress *addr,
131                                     Error **errp)
132 {
133     int fd;
134 
135     trace_qio_channel_socket_connect_sync(ioc, addr);
136     fd = socket_connect(addr, errp, NULL, NULL);
137     if (fd < 0) {
138         trace_qio_channel_socket_connect_fail(ioc);
139         return -1;
140     }
141 
142     trace_qio_channel_socket_connect_complete(ioc, fd);
143     if (qio_channel_socket_set_fd(ioc, fd, errp) < 0) {
144         close(fd);
145         return -1;
146     }
147 
148     return 0;
149 }
150 
151 
152 static int qio_channel_socket_connect_worker(QIOTask *task,
153                                              Error **errp,
154                                              gpointer opaque)
155 {
156     QIOChannelSocket *ioc = QIO_CHANNEL_SOCKET(qio_task_get_source(task));
157     SocketAddress *addr = opaque;
158     int ret;
159 
160     ret = qio_channel_socket_connect_sync(ioc,
161                                           addr,
162                                           errp);
163 
164     object_unref(OBJECT(ioc));
165     return ret;
166 }
167 
168 
169 void qio_channel_socket_connect_async(QIOChannelSocket *ioc,
170                                       SocketAddress *addr,
171                                       QIOTaskFunc callback,
172                                       gpointer opaque,
173                                       GDestroyNotify destroy)
174 {
175     QIOTask *task = qio_task_new(
176         OBJECT(ioc), callback, opaque, destroy);
177     SocketAddress *addrCopy;
178 
179     qapi_copy_SocketAddress(&addrCopy, addr);
180 
181     /* socket_connect() does a non-blocking connect(), but it
182      * still blocks in DNS lookups, so we must use a thread */
183     trace_qio_channel_socket_connect_async(ioc, addr);
184     qio_task_run_in_thread(task,
185                            qio_channel_socket_connect_worker,
186                            addrCopy,
187                            (GDestroyNotify)qapi_free_SocketAddress);
188 }
189 
190 
191 int qio_channel_socket_listen_sync(QIOChannelSocket *ioc,
192                                    SocketAddress *addr,
193                                    Error **errp)
194 {
195     int fd;
196 
197     trace_qio_channel_socket_listen_sync(ioc, addr);
198     fd = socket_listen(addr, errp);
199     if (fd < 0) {
200         trace_qio_channel_socket_listen_fail(ioc);
201         return -1;
202     }
203 
204     trace_qio_channel_socket_listen_complete(ioc, fd);
205     if (qio_channel_socket_set_fd(ioc, fd, errp) < 0) {
206         close(fd);
207         return -1;
208     }
209 
210     return 0;
211 }
212 
213 
214 static int qio_channel_socket_listen_worker(QIOTask *task,
215                                             Error **errp,
216                                             gpointer opaque)
217 {
218     QIOChannelSocket *ioc = QIO_CHANNEL_SOCKET(qio_task_get_source(task));
219     SocketAddress *addr = opaque;
220     int ret;
221 
222     ret = qio_channel_socket_listen_sync(ioc,
223                                          addr,
224                                          errp);
225 
226     object_unref(OBJECT(ioc));
227     return ret;
228 }
229 
230 
231 void qio_channel_socket_listen_async(QIOChannelSocket *ioc,
232                                      SocketAddress *addr,
233                                      QIOTaskFunc callback,
234                                      gpointer opaque,
235                                      GDestroyNotify destroy)
236 {
237     QIOTask *task = qio_task_new(
238         OBJECT(ioc), callback, opaque, destroy);
239     SocketAddress *addrCopy;
240 
241     qapi_copy_SocketAddress(&addrCopy, addr);
242 
243     /* socket_listen() blocks in DNS lookups, so we must use a thread */
244     trace_qio_channel_socket_listen_async(ioc, addr);
245     qio_task_run_in_thread(task,
246                            qio_channel_socket_listen_worker,
247                            addrCopy,
248                            (GDestroyNotify)qapi_free_SocketAddress);
249 }
250 
251 
252 int qio_channel_socket_dgram_sync(QIOChannelSocket *ioc,
253                                   SocketAddress *localAddr,
254                                   SocketAddress *remoteAddr,
255                                   Error **errp)
256 {
257     int fd;
258 
259     trace_qio_channel_socket_dgram_sync(ioc, localAddr, remoteAddr);
260     fd = socket_dgram(localAddr, remoteAddr, errp);
261     if (fd < 0) {
262         trace_qio_channel_socket_dgram_fail(ioc);
263         return -1;
264     }
265 
266     trace_qio_channel_socket_dgram_complete(ioc, fd);
267     if (qio_channel_socket_set_fd(ioc, fd, errp) < 0) {
268         close(fd);
269         return -1;
270     }
271 
272     return 0;
273 }
274 
275 
276 struct QIOChannelSocketDGramWorkerData {
277     SocketAddress *localAddr;
278     SocketAddress *remoteAddr;
279 };
280 
281 
282 static void qio_channel_socket_dgram_worker_free(gpointer opaque)
283 {
284     struct QIOChannelSocketDGramWorkerData *data = opaque;
285     qapi_free_SocketAddress(data->localAddr);
286     qapi_free_SocketAddress(data->remoteAddr);
287     g_free(data);
288 }
289 
290 static int qio_channel_socket_dgram_worker(QIOTask *task,
291                                            Error **errp,
292                                            gpointer opaque)
293 {
294     QIOChannelSocket *ioc = QIO_CHANNEL_SOCKET(qio_task_get_source(task));
295     struct QIOChannelSocketDGramWorkerData *data = opaque;
296     int ret;
297 
298     /* socket_dgram() blocks in DNS lookups, so we must use a thread */
299     ret = qio_channel_socket_dgram_sync(ioc,
300                                         data->localAddr,
301                                         data->remoteAddr,
302                                         errp);
303 
304     object_unref(OBJECT(ioc));
305     return ret;
306 }
307 
308 
309 void qio_channel_socket_dgram_async(QIOChannelSocket *ioc,
310                                     SocketAddress *localAddr,
311                                     SocketAddress *remoteAddr,
312                                     QIOTaskFunc callback,
313                                     gpointer opaque,
314                                     GDestroyNotify destroy)
315 {
316     QIOTask *task = qio_task_new(
317         OBJECT(ioc), callback, opaque, destroy);
318     struct QIOChannelSocketDGramWorkerData *data = g_new0(
319         struct QIOChannelSocketDGramWorkerData, 1);
320 
321     qapi_copy_SocketAddress(&data->localAddr, localAddr);
322     qapi_copy_SocketAddress(&data->remoteAddr, remoteAddr);
323 
324     trace_qio_channel_socket_dgram_async(ioc, localAddr, remoteAddr);
325     qio_task_run_in_thread(task,
326                            qio_channel_socket_dgram_worker,
327                            data,
328                            qio_channel_socket_dgram_worker_free);
329 }
330 
331 
332 QIOChannelSocket *
333 qio_channel_socket_accept(QIOChannelSocket *ioc,
334                           Error **errp)
335 {
336     QIOChannelSocket *cioc;
337 
338     cioc = QIO_CHANNEL_SOCKET(object_new(TYPE_QIO_CHANNEL_SOCKET));
339     cioc->fd = -1;
340     cioc->remoteAddrLen = sizeof(ioc->remoteAddr);
341     cioc->localAddrLen = sizeof(ioc->localAddr);
342 
343  retry:
344     trace_qio_channel_socket_accept(ioc);
345     cioc->fd = accept(ioc->fd, (struct sockaddr *)&cioc->remoteAddr,
346                       &cioc->remoteAddrLen);
347     if (cioc->fd < 0) {
348         trace_qio_channel_socket_accept_fail(ioc);
349         if (socket_error() == EINTR) {
350             goto retry;
351         }
352         goto error;
353     }
354 
355     if (getsockname(cioc->fd, (struct sockaddr *)&ioc->localAddr,
356                     &ioc->localAddrLen) < 0) {
357         error_setg_errno(errp, socket_error(),
358                          "Unable to query local socket address");
359         goto error;
360     }
361 
362     trace_qio_channel_socket_accept_complete(ioc, cioc, cioc->fd);
363     return cioc;
364 
365  error:
366     object_unref(OBJECT(cioc));
367     return NULL;
368 }
369 
370 static void qio_channel_socket_init(Object *obj)
371 {
372     QIOChannelSocket *ioc = QIO_CHANNEL_SOCKET(obj);
373     ioc->fd = -1;
374 }
375 
376 static void qio_channel_socket_finalize(Object *obj)
377 {
378     QIOChannelSocket *ioc = QIO_CHANNEL_SOCKET(obj);
379     if (ioc->fd != -1) {
380         close(ioc->fd);
381         ioc->fd = -1;
382     }
383 }
384 
385 
386 #ifndef WIN32
387 static void qio_channel_socket_copy_fds(struct msghdr *msg,
388                                         int **fds, size_t *nfds)
389 {
390     struct cmsghdr *cmsg;
391 
392     *nfds = 0;
393     *fds = NULL;
394 
395     for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
396         int fd_size, i;
397         int gotfds;
398 
399         if (cmsg->cmsg_len < CMSG_LEN(sizeof(int)) ||
400             cmsg->cmsg_level != SOL_SOCKET ||
401             cmsg->cmsg_type != SCM_RIGHTS) {
402             continue;
403         }
404 
405         fd_size = cmsg->cmsg_len - CMSG_LEN(0);
406 
407         if (!fd_size) {
408             continue;
409         }
410 
411         gotfds = fd_size / sizeof(int);
412         *fds = g_renew(int, *fds, *nfds + gotfds);
413         memcpy(*fds + *nfds, CMSG_DATA(cmsg), fd_size);
414 
415         for (i = 0; i < gotfds; i++) {
416             int fd = (*fds)[*nfds + i];
417             if (fd < 0) {
418                 continue;
419             }
420 
421             /* O_NONBLOCK is preserved across SCM_RIGHTS so reset it */
422             qemu_set_block(fd);
423 
424 #ifndef MSG_CMSG_CLOEXEC
425             qemu_set_cloexec(fd);
426 #endif
427         }
428         *nfds += gotfds;
429     }
430 }
431 
432 
433 static ssize_t qio_channel_socket_readv(QIOChannel *ioc,
434                                         const struct iovec *iov,
435                                         size_t niov,
436                                         int **fds,
437                                         size_t *nfds,
438                                         Error **errp)
439 {
440     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
441     ssize_t ret;
442     struct msghdr msg = { NULL, };
443     char control[CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS)];
444     int sflags = 0;
445 
446 #ifdef MSG_CMSG_CLOEXEC
447     sflags |= MSG_CMSG_CLOEXEC;
448 #endif
449 
450     msg.msg_iov = (struct iovec *)iov;
451     msg.msg_iovlen = niov;
452     if (fds && nfds) {
453         msg.msg_control = control;
454         msg.msg_controllen = sizeof(control);
455     }
456 
457  retry:
458     ret = recvmsg(sioc->fd, &msg, sflags);
459     if (ret < 0) {
460         if (socket_error() == EAGAIN ||
461             socket_error() == EWOULDBLOCK) {
462             return QIO_CHANNEL_ERR_BLOCK;
463         }
464         if (socket_error() == EINTR) {
465             goto retry;
466         }
467 
468         error_setg_errno(errp, socket_error(),
469                          "Unable to read from socket");
470         return -1;
471     }
472 
473     if (fds && nfds) {
474         qio_channel_socket_copy_fds(&msg, fds, nfds);
475     }
476 
477     return ret;
478 }
479 
480 static ssize_t qio_channel_socket_writev(QIOChannel *ioc,
481                                          const struct iovec *iov,
482                                          size_t niov,
483                                          int *fds,
484                                          size_t nfds,
485                                          Error **errp)
486 {
487     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
488     ssize_t ret;
489     struct msghdr msg = { NULL, };
490 
491     msg.msg_iov = (struct iovec *)iov;
492     msg.msg_iovlen = niov;
493 
494     if (nfds) {
495         char control[CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS)];
496         size_t fdsize = sizeof(int) * nfds;
497         struct cmsghdr *cmsg;
498 
499         if (nfds > SOCKET_MAX_FDS) {
500             error_setg_errno(errp, -EINVAL,
501                              "Only %d FDs can be sent, got %zu",
502                              SOCKET_MAX_FDS, nfds);
503             return -1;
504         }
505 
506         msg.msg_control = control;
507         msg.msg_controllen = CMSG_SPACE(sizeof(int) * nfds);
508 
509         cmsg = CMSG_FIRSTHDR(&msg);
510         cmsg->cmsg_len = CMSG_LEN(fdsize);
511         cmsg->cmsg_level = SOL_SOCKET;
512         cmsg->cmsg_type = SCM_RIGHTS;
513         memcpy(CMSG_DATA(cmsg), fds, fdsize);
514     }
515 
516  retry:
517     ret = sendmsg(sioc->fd, &msg, 0);
518     if (ret <= 0) {
519         if (socket_error() == EAGAIN ||
520             socket_error() == EWOULDBLOCK) {
521             return QIO_CHANNEL_ERR_BLOCK;
522         }
523         if (socket_error() == EINTR) {
524             goto retry;
525         }
526         error_setg_errno(errp, socket_error(),
527                          "Unable to write to socket");
528         return -1;
529     }
530     return ret;
531 }
532 #else /* WIN32 */
533 static ssize_t qio_channel_socket_readv(QIOChannel *ioc,
534                                         const struct iovec *iov,
535                                         size_t niov,
536                                         int **fds,
537                                         size_t *nfds,
538                                         Error **errp)
539 {
540     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
541     ssize_t done = 0;
542     ssize_t i;
543 
544     for (i = 0; i < niov; i++) {
545         ssize_t ret;
546     retry:
547         ret = recv(sioc->fd,
548                    iov[i].iov_base,
549                    iov[i].iov_len,
550                    0);
551         if (ret < 0) {
552             if (socket_error() == EAGAIN) {
553                 if (done) {
554                     return done;
555                 } else {
556                     return QIO_CHANNEL_ERR_BLOCK;
557                 }
558             } else if (socket_error() == EINTR) {
559                 goto retry;
560             } else {
561                 error_setg_errno(errp, socket_error(),
562                                  "Unable to write to socket");
563                 return -1;
564             }
565         }
566         done += ret;
567         if (ret < iov[i].iov_len) {
568             return done;
569         }
570     }
571 
572     return done;
573 }
574 
575 static ssize_t qio_channel_socket_writev(QIOChannel *ioc,
576                                          const struct iovec *iov,
577                                          size_t niov,
578                                          int *fds,
579                                          size_t nfds,
580                                          Error **errp)
581 {
582     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
583     ssize_t done = 0;
584     ssize_t i;
585 
586     for (i = 0; i < niov; i++) {
587         ssize_t ret;
588     retry:
589         ret = send(sioc->fd,
590                    iov[i].iov_base,
591                    iov[i].iov_len,
592                    0);
593         if (ret < 0) {
594             if (socket_error() == EAGAIN) {
595                 if (done) {
596                     return done;
597                 } else {
598                     return QIO_CHANNEL_ERR_BLOCK;
599                 }
600             } else if (socket_error() == EINTR) {
601                 goto retry;
602             } else {
603                 error_setg_errno(errp, socket_error(),
604                                  "Unable to write to socket");
605                 return -1;
606             }
607         }
608         done += ret;
609         if (ret < iov[i].iov_len) {
610             return done;
611         }
612     }
613 
614     return done;
615 }
616 #endif /* WIN32 */
617 
618 static int
619 qio_channel_socket_set_blocking(QIOChannel *ioc,
620                                 bool enabled,
621                                 Error **errp)
622 {
623     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
624 
625     if (enabled) {
626         qemu_set_block(sioc->fd);
627     } else {
628         qemu_set_nonblock(sioc->fd);
629     }
630     return 0;
631 }
632 
633 
634 static void
635 qio_channel_socket_set_delay(QIOChannel *ioc,
636                              bool enabled)
637 {
638     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
639     int v = enabled ? 0 : 1;
640 
641     qemu_setsockopt(sioc->fd,
642                     IPPROTO_TCP, TCP_NODELAY,
643                     &v, sizeof(v));
644 }
645 
646 
647 static void
648 qio_channel_socket_set_cork(QIOChannel *ioc,
649                             bool enabled)
650 {
651     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
652     int v = enabled ? 1 : 0;
653 
654     socket_set_cork(sioc->fd, v);
655 }
656 
657 
658 static int
659 qio_channel_socket_close(QIOChannel *ioc,
660                          Error **errp)
661 {
662     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
663 
664     if (closesocket(sioc->fd) < 0) {
665         sioc->fd = -1;
666         error_setg_errno(errp, socket_error(),
667                          "Unable to close socket");
668         return -1;
669     }
670     sioc->fd = -1;
671     return 0;
672 }
673 
674 static int
675 qio_channel_socket_shutdown(QIOChannel *ioc,
676                             QIOChannelShutdown how,
677                             Error **errp)
678 {
679     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
680     int sockhow;
681 
682     switch (how) {
683     case QIO_CHANNEL_SHUTDOWN_READ:
684         sockhow = SHUT_RD;
685         break;
686     case QIO_CHANNEL_SHUTDOWN_WRITE:
687         sockhow = SHUT_WR;
688         break;
689     case QIO_CHANNEL_SHUTDOWN_BOTH:
690     default:
691         sockhow = SHUT_RDWR;
692         break;
693     }
694 
695     if (shutdown(sioc->fd, sockhow) < 0) {
696         error_setg_errno(errp, socket_error(),
697                          "Unable to shutdown socket");
698         return -1;
699     }
700     return 0;
701 }
702 
703 static GSource *qio_channel_socket_create_watch(QIOChannel *ioc,
704                                                 GIOCondition condition)
705 {
706     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
707     return qio_channel_create_fd_watch(ioc,
708                                        sioc->fd,
709                                        condition);
710 }
711 
712 static void qio_channel_socket_class_init(ObjectClass *klass,
713                                           void *class_data G_GNUC_UNUSED)
714 {
715     QIOChannelClass *ioc_klass = QIO_CHANNEL_CLASS(klass);
716 
717     ioc_klass->io_writev = qio_channel_socket_writev;
718     ioc_klass->io_readv = qio_channel_socket_readv;
719     ioc_klass->io_set_blocking = qio_channel_socket_set_blocking;
720     ioc_klass->io_close = qio_channel_socket_close;
721     ioc_klass->io_shutdown = qio_channel_socket_shutdown;
722     ioc_klass->io_set_cork = qio_channel_socket_set_cork;
723     ioc_klass->io_set_delay = qio_channel_socket_set_delay;
724     ioc_klass->io_create_watch = qio_channel_socket_create_watch;
725 }
726 
727 static const TypeInfo qio_channel_socket_info = {
728     .parent = TYPE_QIO_CHANNEL,
729     .name = TYPE_QIO_CHANNEL_SOCKET,
730     .instance_size = sizeof(QIOChannelSocket),
731     .instance_init = qio_channel_socket_init,
732     .instance_finalize = qio_channel_socket_finalize,
733     .class_init = qio_channel_socket_class_init,
734 };
735 
736 static void qio_channel_socket_register_types(void)
737 {
738     type_register_static(&qio_channel_socket_info);
739 }
740 
741 type_init(qio_channel_socket_register_types);
742