xref: /openbmc/qemu/net/net.c (revision ab938ae4)
1 /*
2  * QEMU System Emulator
3  *
4  * Copyright (c) 2003-2008 Fabrice Bellard
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 #include "qemu/osdep.h"
25 
26 #include "net/net.h"
27 #include "clients.h"
28 #include "hub.h"
29 #include "net/slirp.h"
30 #include "net/eth.h"
31 #include "util.h"
32 
33 #include "monitor/monitor.h"
34 #include "qemu-common.h"
35 #include "qemu/help_option.h"
36 #include "qapi/qmp/qerror.h"
37 #include "qemu/error-report.h"
38 #include "qemu/sockets.h"
39 #include "qemu/cutils.h"
40 #include "qemu/config-file.h"
41 #include "qmp-commands.h"
42 #include "hw/qdev.h"
43 #include "qemu/iov.h"
44 #include "qemu/main-loop.h"
45 #include "qapi-visit.h"
46 #include "qapi/opts-visitor.h"
47 #include "sysemu/sysemu.h"
48 #include "sysemu/qtest.h"
49 #include "net/filter.h"
50 #include "qapi/string-output-visitor.h"
51 
52 /* Net bridge is currently not supported for W32. */
53 #if !defined(_WIN32)
54 # define CONFIG_NET_BRIDGE
55 #endif
56 
57 static VMChangeStateEntry *net_change_state_entry;
58 static QTAILQ_HEAD(, NetClientState) net_clients;
59 
60 const char *host_net_devices[] = {
61     "tap",
62     "socket",
63     "dump",
64 #ifdef CONFIG_NET_BRIDGE
65     "bridge",
66 #endif
67 #ifdef CONFIG_NETMAP
68     "netmap",
69 #endif
70 #ifdef CONFIG_SLIRP
71     "user",
72 #endif
73 #ifdef CONFIG_VDE
74     "vde",
75 #endif
76     "vhost-user",
77     NULL,
78 };
79 
80 /***********************************************************/
81 /* network device redirectors */
82 
83 static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
84 {
85     const char *p, *p1;
86     int len;
87     p = *pp;
88     p1 = strchr(p, sep);
89     if (!p1)
90         return -1;
91     len = p1 - p;
92     p1++;
93     if (buf_size > 0) {
94         if (len > buf_size - 1)
95             len = buf_size - 1;
96         memcpy(buf, p, len);
97         buf[len] = '\0';
98     }
99     *pp = p1;
100     return 0;
101 }
102 
103 int parse_host_port(struct sockaddr_in *saddr, const char *str,
104                     Error **errp)
105 {
106     char buf[512];
107     struct hostent *he;
108     const char *p, *r;
109     int port;
110 
111     p = str;
112     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
113         error_setg(errp, "host address '%s' doesn't contain ':' "
114                    "separating host from port", str);
115         return -1;
116     }
117     saddr->sin_family = AF_INET;
118     if (buf[0] == '\0') {
119         saddr->sin_addr.s_addr = 0;
120     } else {
121         if (qemu_isdigit(buf[0])) {
122             if (!inet_aton(buf, &saddr->sin_addr)) {
123                 error_setg(errp, "host address '%s' is not a valid "
124                            "IPv4 address", buf);
125                 return -1;
126             }
127         } else {
128             he = gethostbyname(buf);
129             if (he == NULL) {
130                 error_setg(errp, "can't resolve host address '%s'", buf);
131                 return - 1;
132             }
133             saddr->sin_addr = *(struct in_addr *)he->h_addr;
134         }
135     }
136     port = strtol(p, (char **)&r, 0);
137     if (r == p) {
138         error_setg(errp, "port number '%s' is invalid", p);
139         return -1;
140     }
141     saddr->sin_port = htons(port);
142     return 0;
143 }
144 
145 char *qemu_mac_strdup_printf(const uint8_t *macaddr)
146 {
147     return g_strdup_printf("%.2x:%.2x:%.2x:%.2x:%.2x:%.2x",
148                            macaddr[0], macaddr[1], macaddr[2],
149                            macaddr[3], macaddr[4], macaddr[5]);
150 }
151 
152 void qemu_format_nic_info_str(NetClientState *nc, uint8_t macaddr[6])
153 {
154     snprintf(nc->info_str, sizeof(nc->info_str),
155              "model=%s,macaddr=%02x:%02x:%02x:%02x:%02x:%02x",
156              nc->model,
157              macaddr[0], macaddr[1], macaddr[2],
158              macaddr[3], macaddr[4], macaddr[5]);
159 }
160 
161 static int mac_table[256] = {0};
162 
163 static void qemu_macaddr_set_used(MACAddr *macaddr)
164 {
165     int index;
166 
167     for (index = 0x56; index < 0xFF; index++) {
168         if (macaddr->a[5] == index) {
169             mac_table[index]++;
170         }
171     }
172 }
173 
174 static void qemu_macaddr_set_free(MACAddr *macaddr)
175 {
176     int index;
177     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
178 
179     if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
180         return;
181     }
182     for (index = 0x56; index < 0xFF; index++) {
183         if (macaddr->a[5] == index) {
184             mac_table[index]--;
185         }
186     }
187 }
188 
189 static int qemu_macaddr_get_free(void)
190 {
191     int index;
192 
193     for (index = 0x56; index < 0xFF; index++) {
194         if (mac_table[index] == 0) {
195             return index;
196         }
197     }
198 
199     return -1;
200 }
201 
202 void qemu_macaddr_default_if_unset(MACAddr *macaddr)
203 {
204     static const MACAddr zero = { .a = { 0,0,0,0,0,0 } };
205     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
206 
207     if (memcmp(macaddr, &zero, sizeof(zero)) != 0) {
208         if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
209             return;
210         } else {
211             qemu_macaddr_set_used(macaddr);
212             return;
213         }
214     }
215 
216     macaddr->a[0] = 0x52;
217     macaddr->a[1] = 0x54;
218     macaddr->a[2] = 0x00;
219     macaddr->a[3] = 0x12;
220     macaddr->a[4] = 0x34;
221     macaddr->a[5] = qemu_macaddr_get_free();
222     qemu_macaddr_set_used(macaddr);
223 }
224 
225 /**
226  * Generate a name for net client
227  *
228  * Only net clients created with the legacy -net option and NICs need this.
229  */
230 static char *assign_name(NetClientState *nc1, const char *model)
231 {
232     NetClientState *nc;
233     int id = 0;
234 
235     QTAILQ_FOREACH(nc, &net_clients, next) {
236         if (nc == nc1) {
237             continue;
238         }
239         if (strcmp(nc->model, model) == 0) {
240             id++;
241         }
242     }
243 
244     return g_strdup_printf("%s.%d", model, id);
245 }
246 
247 static void qemu_net_client_destructor(NetClientState *nc)
248 {
249     g_free(nc);
250 }
251 
252 static void qemu_net_client_setup(NetClientState *nc,
253                                   NetClientInfo *info,
254                                   NetClientState *peer,
255                                   const char *model,
256                                   const char *name,
257                                   NetClientDestructor *destructor)
258 {
259     nc->info = info;
260     nc->model = g_strdup(model);
261     if (name) {
262         nc->name = g_strdup(name);
263     } else {
264         nc->name = assign_name(nc, model);
265     }
266 
267     if (peer) {
268         assert(!peer->peer);
269         nc->peer = peer;
270         peer->peer = nc;
271     }
272     QTAILQ_INSERT_TAIL(&net_clients, nc, next);
273 
274     nc->incoming_queue = qemu_new_net_queue(qemu_deliver_packet_iov, nc);
275     nc->destructor = destructor;
276     QTAILQ_INIT(&nc->filters);
277 }
278 
279 NetClientState *qemu_new_net_client(NetClientInfo *info,
280                                     NetClientState *peer,
281                                     const char *model,
282                                     const char *name)
283 {
284     NetClientState *nc;
285 
286     assert(info->size >= sizeof(NetClientState));
287 
288     nc = g_malloc0(info->size);
289     qemu_net_client_setup(nc, info, peer, model, name,
290                           qemu_net_client_destructor);
291 
292     return nc;
293 }
294 
295 NICState *qemu_new_nic(NetClientInfo *info,
296                        NICConf *conf,
297                        const char *model,
298                        const char *name,
299                        void *opaque)
300 {
301     NetClientState **peers = conf->peers.ncs;
302     NICState *nic;
303     int i, queues = MAX(1, conf->peers.queues);
304 
305     assert(info->type == NET_CLIENT_DRIVER_NIC);
306     assert(info->size >= sizeof(NICState));
307 
308     nic = g_malloc0(info->size + sizeof(NetClientState) * queues);
309     nic->ncs = (void *)nic + info->size;
310     nic->conf = conf;
311     nic->opaque = opaque;
312 
313     for (i = 0; i < queues; i++) {
314         qemu_net_client_setup(&nic->ncs[i], info, peers[i], model, name,
315                               NULL);
316         nic->ncs[i].queue_index = i;
317     }
318 
319     return nic;
320 }
321 
322 NetClientState *qemu_get_subqueue(NICState *nic, int queue_index)
323 {
324     return nic->ncs + queue_index;
325 }
326 
327 NetClientState *qemu_get_queue(NICState *nic)
328 {
329     return qemu_get_subqueue(nic, 0);
330 }
331 
332 NICState *qemu_get_nic(NetClientState *nc)
333 {
334     NetClientState *nc0 = nc - nc->queue_index;
335 
336     return (NICState *)((void *)nc0 - nc->info->size);
337 }
338 
339 void *qemu_get_nic_opaque(NetClientState *nc)
340 {
341     NICState *nic = qemu_get_nic(nc);
342 
343     return nic->opaque;
344 }
345 
346 static void qemu_cleanup_net_client(NetClientState *nc)
347 {
348     QTAILQ_REMOVE(&net_clients, nc, next);
349 
350     if (nc->info->cleanup) {
351         nc->info->cleanup(nc);
352     }
353 }
354 
355 static void qemu_free_net_client(NetClientState *nc)
356 {
357     if (nc->incoming_queue) {
358         qemu_del_net_queue(nc->incoming_queue);
359     }
360     if (nc->peer) {
361         nc->peer->peer = NULL;
362     }
363     g_free(nc->name);
364     g_free(nc->model);
365     if (nc->destructor) {
366         nc->destructor(nc);
367     }
368 }
369 
370 void qemu_del_net_client(NetClientState *nc)
371 {
372     NetClientState *ncs[MAX_QUEUE_NUM];
373     int queues, i;
374     NetFilterState *nf, *next;
375 
376     assert(nc->info->type != NET_CLIENT_DRIVER_NIC);
377 
378     /* If the NetClientState belongs to a multiqueue backend, we will change all
379      * other NetClientStates also.
380      */
381     queues = qemu_find_net_clients_except(nc->name, ncs,
382                                           NET_CLIENT_DRIVER_NIC,
383                                           MAX_QUEUE_NUM);
384     assert(queues != 0);
385 
386     QTAILQ_FOREACH_SAFE(nf, &nc->filters, next, next) {
387         object_unparent(OBJECT(nf));
388     }
389 
390     /* If there is a peer NIC, delete and cleanup client, but do not free. */
391     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
392         NICState *nic = qemu_get_nic(nc->peer);
393         if (nic->peer_deleted) {
394             return;
395         }
396         nic->peer_deleted = true;
397 
398         for (i = 0; i < queues; i++) {
399             ncs[i]->peer->link_down = true;
400         }
401 
402         if (nc->peer->info->link_status_changed) {
403             nc->peer->info->link_status_changed(nc->peer);
404         }
405 
406         for (i = 0; i < queues; i++) {
407             qemu_cleanup_net_client(ncs[i]);
408         }
409 
410         return;
411     }
412 
413     for (i = 0; i < queues; i++) {
414         qemu_cleanup_net_client(ncs[i]);
415         qemu_free_net_client(ncs[i]);
416     }
417 }
418 
419 void qemu_del_nic(NICState *nic)
420 {
421     int i, queues = MAX(nic->conf->peers.queues, 1);
422 
423     qemu_macaddr_set_free(&nic->conf->macaddr);
424 
425     /* If this is a peer NIC and peer has already been deleted, free it now. */
426     if (nic->peer_deleted) {
427         for (i = 0; i < queues; i++) {
428             qemu_free_net_client(qemu_get_subqueue(nic, i)->peer);
429         }
430     }
431 
432     for (i = queues - 1; i >= 0; i--) {
433         NetClientState *nc = qemu_get_subqueue(nic, i);
434 
435         qemu_cleanup_net_client(nc);
436         qemu_free_net_client(nc);
437     }
438 
439     g_free(nic);
440 }
441 
442 void qemu_foreach_nic(qemu_nic_foreach func, void *opaque)
443 {
444     NetClientState *nc;
445 
446     QTAILQ_FOREACH(nc, &net_clients, next) {
447         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
448             if (nc->queue_index == 0) {
449                 func(qemu_get_nic(nc), opaque);
450             }
451         }
452     }
453 }
454 
455 bool qemu_has_ufo(NetClientState *nc)
456 {
457     if (!nc || !nc->info->has_ufo) {
458         return false;
459     }
460 
461     return nc->info->has_ufo(nc);
462 }
463 
464 bool qemu_has_vnet_hdr(NetClientState *nc)
465 {
466     if (!nc || !nc->info->has_vnet_hdr) {
467         return false;
468     }
469 
470     return nc->info->has_vnet_hdr(nc);
471 }
472 
473 bool qemu_has_vnet_hdr_len(NetClientState *nc, int len)
474 {
475     if (!nc || !nc->info->has_vnet_hdr_len) {
476         return false;
477     }
478 
479     return nc->info->has_vnet_hdr_len(nc, len);
480 }
481 
482 void qemu_using_vnet_hdr(NetClientState *nc, bool enable)
483 {
484     if (!nc || !nc->info->using_vnet_hdr) {
485         return;
486     }
487 
488     nc->info->using_vnet_hdr(nc, enable);
489 }
490 
491 void qemu_set_offload(NetClientState *nc, int csum, int tso4, int tso6,
492                           int ecn, int ufo)
493 {
494     if (!nc || !nc->info->set_offload) {
495         return;
496     }
497 
498     nc->info->set_offload(nc, csum, tso4, tso6, ecn, ufo);
499 }
500 
501 void qemu_set_vnet_hdr_len(NetClientState *nc, int len)
502 {
503     if (!nc || !nc->info->set_vnet_hdr_len) {
504         return;
505     }
506 
507     nc->vnet_hdr_len = len;
508     nc->info->set_vnet_hdr_len(nc, len);
509 }
510 
511 int qemu_set_vnet_le(NetClientState *nc, bool is_le)
512 {
513 #ifdef HOST_WORDS_BIGENDIAN
514     if (!nc || !nc->info->set_vnet_le) {
515         return -ENOSYS;
516     }
517 
518     return nc->info->set_vnet_le(nc, is_le);
519 #else
520     return 0;
521 #endif
522 }
523 
524 int qemu_set_vnet_be(NetClientState *nc, bool is_be)
525 {
526 #ifdef HOST_WORDS_BIGENDIAN
527     return 0;
528 #else
529     if (!nc || !nc->info->set_vnet_be) {
530         return -ENOSYS;
531     }
532 
533     return nc->info->set_vnet_be(nc, is_be);
534 #endif
535 }
536 
537 int qemu_can_send_packet(NetClientState *sender)
538 {
539     int vm_running = runstate_is_running();
540 
541     if (!vm_running) {
542         return 0;
543     }
544 
545     if (!sender->peer) {
546         return 1;
547     }
548 
549     if (sender->peer->receive_disabled) {
550         return 0;
551     } else if (sender->peer->info->can_receive &&
552                !sender->peer->info->can_receive(sender->peer)) {
553         return 0;
554     }
555     return 1;
556 }
557 
558 static ssize_t filter_receive_iov(NetClientState *nc,
559                                   NetFilterDirection direction,
560                                   NetClientState *sender,
561                                   unsigned flags,
562                                   const struct iovec *iov,
563                                   int iovcnt,
564                                   NetPacketSent *sent_cb)
565 {
566     ssize_t ret = 0;
567     NetFilterState *nf = NULL;
568 
569     if (direction == NET_FILTER_DIRECTION_TX) {
570         QTAILQ_FOREACH(nf, &nc->filters, next) {
571             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
572                                          iovcnt, sent_cb);
573             if (ret) {
574                 return ret;
575             }
576         }
577     } else {
578         QTAILQ_FOREACH_REVERSE(nf, &nc->filters, NetFilterHead, next) {
579             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
580                                          iovcnt, sent_cb);
581             if (ret) {
582                 return ret;
583             }
584         }
585     }
586 
587     return ret;
588 }
589 
590 static ssize_t filter_receive(NetClientState *nc,
591                               NetFilterDirection direction,
592                               NetClientState *sender,
593                               unsigned flags,
594                               const uint8_t *data,
595                               size_t size,
596                               NetPacketSent *sent_cb)
597 {
598     struct iovec iov = {
599         .iov_base = (void *)data,
600         .iov_len = size
601     };
602 
603     return filter_receive_iov(nc, direction, sender, flags, &iov, 1, sent_cb);
604 }
605 
606 void qemu_purge_queued_packets(NetClientState *nc)
607 {
608     if (!nc->peer) {
609         return;
610     }
611 
612     qemu_net_queue_purge(nc->peer->incoming_queue, nc);
613 }
614 
615 static
616 void qemu_flush_or_purge_queued_packets(NetClientState *nc, bool purge)
617 {
618     nc->receive_disabled = 0;
619 
620     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_HUBPORT) {
621         if (net_hub_flush(nc->peer)) {
622             qemu_notify_event();
623         }
624     }
625     if (qemu_net_queue_flush(nc->incoming_queue)) {
626         /* We emptied the queue successfully, signal to the IO thread to repoll
627          * the file descriptor (for tap, for example).
628          */
629         qemu_notify_event();
630     } else if (purge) {
631         /* Unable to empty the queue, purge remaining packets */
632         qemu_net_queue_purge(nc->incoming_queue, nc);
633     }
634 }
635 
636 void qemu_flush_queued_packets(NetClientState *nc)
637 {
638     qemu_flush_or_purge_queued_packets(nc, false);
639 }
640 
641 static ssize_t qemu_send_packet_async_with_flags(NetClientState *sender,
642                                                  unsigned flags,
643                                                  const uint8_t *buf, int size,
644                                                  NetPacketSent *sent_cb)
645 {
646     NetQueue *queue;
647     int ret;
648 
649 #ifdef DEBUG_NET
650     printf("qemu_send_packet_async:\n");
651     qemu_hexdump((const char *)buf, stdout, "net", size);
652 #endif
653 
654     if (sender->link_down || !sender->peer) {
655         return size;
656     }
657 
658     /* Let filters handle the packet first */
659     ret = filter_receive(sender, NET_FILTER_DIRECTION_TX,
660                          sender, flags, buf, size, sent_cb);
661     if (ret) {
662         return ret;
663     }
664 
665     ret = filter_receive(sender->peer, NET_FILTER_DIRECTION_RX,
666                          sender, flags, buf, size, sent_cb);
667     if (ret) {
668         return ret;
669     }
670 
671     queue = sender->peer->incoming_queue;
672 
673     return qemu_net_queue_send(queue, sender, flags, buf, size, sent_cb);
674 }
675 
676 ssize_t qemu_send_packet_async(NetClientState *sender,
677                                const uint8_t *buf, int size,
678                                NetPacketSent *sent_cb)
679 {
680     return qemu_send_packet_async_with_flags(sender, QEMU_NET_PACKET_FLAG_NONE,
681                                              buf, size, sent_cb);
682 }
683 
684 void qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size)
685 {
686     qemu_send_packet_async(nc, buf, size, NULL);
687 }
688 
689 ssize_t qemu_send_packet_raw(NetClientState *nc, const uint8_t *buf, int size)
690 {
691     return qemu_send_packet_async_with_flags(nc, QEMU_NET_PACKET_FLAG_RAW,
692                                              buf, size, NULL);
693 }
694 
695 static ssize_t nc_sendv_compat(NetClientState *nc, const struct iovec *iov,
696                                int iovcnt, unsigned flags)
697 {
698     uint8_t *buf = NULL;
699     uint8_t *buffer;
700     size_t offset;
701     ssize_t ret;
702 
703     if (iovcnt == 1) {
704         buffer = iov[0].iov_base;
705         offset = iov[0].iov_len;
706     } else {
707         offset = iov_size(iov, iovcnt);
708         if (offset > NET_BUFSIZE) {
709             return -1;
710         }
711         buf = g_malloc(offset);
712         buffer = buf;
713         offset = iov_to_buf(iov, iovcnt, 0, buf, offset);
714     }
715 
716     if (flags & QEMU_NET_PACKET_FLAG_RAW && nc->info->receive_raw) {
717         ret = nc->info->receive_raw(nc, buffer, offset);
718     } else {
719         ret = nc->info->receive(nc, buffer, offset);
720     }
721 
722     g_free(buf);
723     return ret;
724 }
725 
726 ssize_t qemu_deliver_packet_iov(NetClientState *sender,
727                                 unsigned flags,
728                                 const struct iovec *iov,
729                                 int iovcnt,
730                                 void *opaque)
731 {
732     NetClientState *nc = opaque;
733     int ret;
734 
735     if (nc->link_down) {
736         return iov_size(iov, iovcnt);
737     }
738 
739     if (nc->receive_disabled) {
740         return 0;
741     }
742 
743     if (nc->info->receive_iov && !(flags & QEMU_NET_PACKET_FLAG_RAW)) {
744         ret = nc->info->receive_iov(nc, iov, iovcnt);
745     } else {
746         ret = nc_sendv_compat(nc, iov, iovcnt, flags);
747     }
748 
749     if (ret == 0) {
750         nc->receive_disabled = 1;
751     }
752 
753     return ret;
754 }
755 
756 ssize_t qemu_sendv_packet_async(NetClientState *sender,
757                                 const struct iovec *iov, int iovcnt,
758                                 NetPacketSent *sent_cb)
759 {
760     NetQueue *queue;
761     int ret;
762 
763     if (sender->link_down || !sender->peer) {
764         return iov_size(iov, iovcnt);
765     }
766 
767     /* Let filters handle the packet first */
768     ret = filter_receive_iov(sender, NET_FILTER_DIRECTION_TX, sender,
769                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
770     if (ret) {
771         return ret;
772     }
773 
774     ret = filter_receive_iov(sender->peer, NET_FILTER_DIRECTION_RX, sender,
775                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
776     if (ret) {
777         return ret;
778     }
779 
780     queue = sender->peer->incoming_queue;
781 
782     return qemu_net_queue_send_iov(queue, sender,
783                                    QEMU_NET_PACKET_FLAG_NONE,
784                                    iov, iovcnt, sent_cb);
785 }
786 
787 ssize_t
788 qemu_sendv_packet(NetClientState *nc, const struct iovec *iov, int iovcnt)
789 {
790     return qemu_sendv_packet_async(nc, iov, iovcnt, NULL);
791 }
792 
793 NetClientState *qemu_find_netdev(const char *id)
794 {
795     NetClientState *nc;
796 
797     QTAILQ_FOREACH(nc, &net_clients, next) {
798         if (nc->info->type == NET_CLIENT_DRIVER_NIC)
799             continue;
800         if (!strcmp(nc->name, id)) {
801             return nc;
802         }
803     }
804 
805     return NULL;
806 }
807 
808 int qemu_find_net_clients_except(const char *id, NetClientState **ncs,
809                                  NetClientDriver type, int max)
810 {
811     NetClientState *nc;
812     int ret = 0;
813 
814     QTAILQ_FOREACH(nc, &net_clients, next) {
815         if (nc->info->type == type) {
816             continue;
817         }
818         if (!id || !strcmp(nc->name, id)) {
819             if (ret < max) {
820                 ncs[ret] = nc;
821             }
822             ret++;
823         }
824     }
825 
826     return ret;
827 }
828 
829 static int nic_get_free_idx(void)
830 {
831     int index;
832 
833     for (index = 0; index < MAX_NICS; index++)
834         if (!nd_table[index].used)
835             return index;
836     return -1;
837 }
838 
839 int qemu_show_nic_models(const char *arg, const char *const *models)
840 {
841     int i;
842 
843     if (!arg || !is_help_option(arg)) {
844         return 0;
845     }
846 
847     fprintf(stderr, "qemu: Supported NIC models: ");
848     for (i = 0 ; models[i]; i++)
849         fprintf(stderr, "%s%c", models[i], models[i+1] ? ',' : '\n');
850     return 1;
851 }
852 
853 void qemu_check_nic_model(NICInfo *nd, const char *model)
854 {
855     const char *models[2];
856 
857     models[0] = model;
858     models[1] = NULL;
859 
860     if (qemu_show_nic_models(nd->model, models))
861         exit(0);
862     if (qemu_find_nic_model(nd, models, model) < 0)
863         exit(1);
864 }
865 
866 int qemu_find_nic_model(NICInfo *nd, const char * const *models,
867                         const char *default_model)
868 {
869     int i;
870 
871     if (!nd->model)
872         nd->model = g_strdup(default_model);
873 
874     for (i = 0 ; models[i]; i++) {
875         if (strcmp(nd->model, models[i]) == 0)
876             return i;
877     }
878 
879     error_report("Unsupported NIC model: %s", nd->model);
880     return -1;
881 }
882 
883 static int net_init_nic(const Netdev *netdev, const char *name,
884                         NetClientState *peer, Error **errp)
885 {
886     int idx;
887     NICInfo *nd;
888     const NetLegacyNicOptions *nic;
889 
890     assert(netdev->type == NET_CLIENT_DRIVER_NIC);
891     nic = &netdev->u.nic;
892 
893     idx = nic_get_free_idx();
894     if (idx == -1 || nb_nics >= MAX_NICS) {
895         error_setg(errp, "too many NICs");
896         return -1;
897     }
898 
899     nd = &nd_table[idx];
900 
901     memset(nd, 0, sizeof(*nd));
902 
903     if (nic->has_netdev) {
904         nd->netdev = qemu_find_netdev(nic->netdev);
905         if (!nd->netdev) {
906             error_setg(errp, "netdev '%s' not found", nic->netdev);
907             return -1;
908         }
909     } else {
910         assert(peer);
911         nd->netdev = peer;
912     }
913     nd->name = g_strdup(name);
914     if (nic->has_model) {
915         nd->model = g_strdup(nic->model);
916     }
917     if (nic->has_addr) {
918         nd->devaddr = g_strdup(nic->addr);
919     }
920 
921     if (nic->has_macaddr &&
922         net_parse_macaddr(nd->macaddr.a, nic->macaddr) < 0) {
923         error_setg(errp, "invalid syntax for ethernet address");
924         return -1;
925     }
926     if (nic->has_macaddr &&
927         is_multicast_ether_addr(nd->macaddr.a)) {
928         error_setg(errp,
929                    "NIC cannot have multicast MAC address (odd 1st byte)");
930         return -1;
931     }
932     qemu_macaddr_default_if_unset(&nd->macaddr);
933 
934     if (nic->has_vectors) {
935         if (nic->vectors > 0x7ffffff) {
936             error_setg(errp, "invalid # of vectors: %"PRIu32, nic->vectors);
937             return -1;
938         }
939         nd->nvectors = nic->vectors;
940     } else {
941         nd->nvectors = DEV_NVECTORS_UNSPECIFIED;
942     }
943 
944     nd->used = 1;
945     nb_nics++;
946 
947     return idx;
948 }
949 
950 
951 static int (* const net_client_init_fun[NET_CLIENT_DRIVER__MAX])(
952     const Netdev *netdev,
953     const char *name,
954     NetClientState *peer, Error **errp) = {
955         [NET_CLIENT_DRIVER_NIC]       = net_init_nic,
956 #ifdef CONFIG_SLIRP
957         [NET_CLIENT_DRIVER_USER]      = net_init_slirp,
958 #endif
959         [NET_CLIENT_DRIVER_TAP]       = net_init_tap,
960         [NET_CLIENT_DRIVER_SOCKET]    = net_init_socket,
961 #ifdef CONFIG_VDE
962         [NET_CLIENT_DRIVER_VDE]       = net_init_vde,
963 #endif
964 #ifdef CONFIG_NETMAP
965         [NET_CLIENT_DRIVER_NETMAP]    = net_init_netmap,
966 #endif
967         [NET_CLIENT_DRIVER_DUMP]      = net_init_dump,
968 #ifdef CONFIG_NET_BRIDGE
969         [NET_CLIENT_DRIVER_BRIDGE]    = net_init_bridge,
970 #endif
971         [NET_CLIENT_DRIVER_HUBPORT]   = net_init_hubport,
972 #ifdef CONFIG_VHOST_NET_USED
973         [NET_CLIENT_DRIVER_VHOST_USER] = net_init_vhost_user,
974 #endif
975 #ifdef CONFIG_L2TPV3
976         [NET_CLIENT_DRIVER_L2TPV3]    = net_init_l2tpv3,
977 #endif
978 };
979 
980 
981 static int net_client_init1(const void *object, bool is_netdev, Error **errp)
982 {
983     Netdev legacy = {0};
984     const Netdev *netdev;
985     const char *name;
986     NetClientState *peer = NULL;
987     static bool vlan_warned;
988 
989     if (is_netdev) {
990         netdev = object;
991         name = netdev->id;
992 
993         if (netdev->type == NET_CLIENT_DRIVER_DUMP ||
994             netdev->type == NET_CLIENT_DRIVER_NIC ||
995             !net_client_init_fun[netdev->type]) {
996             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
997                        "a netdev backend type");
998             return -1;
999         }
1000     } else {
1001         const NetLegacy *net = object;
1002         const NetLegacyOptions *opts = net->opts;
1003         legacy.id = net->id;
1004         netdev = &legacy;
1005         /* missing optional values have been initialized to "all bits zero" */
1006         name = net->has_id ? net->id : net->name;
1007 
1008         /* Map the old options to the new flat type */
1009         switch (opts->type) {
1010         case NET_LEGACY_OPTIONS_TYPE_NONE:
1011             return 0; /* nothing to do */
1012         case NET_LEGACY_OPTIONS_TYPE_NIC:
1013             legacy.type = NET_CLIENT_DRIVER_NIC;
1014             legacy.u.nic = opts->u.nic;
1015             break;
1016         case NET_LEGACY_OPTIONS_TYPE_USER:
1017             legacy.type = NET_CLIENT_DRIVER_USER;
1018             legacy.u.user = opts->u.user;
1019             break;
1020         case NET_LEGACY_OPTIONS_TYPE_TAP:
1021             legacy.type = NET_CLIENT_DRIVER_TAP;
1022             legacy.u.tap = opts->u.tap;
1023             break;
1024         case NET_LEGACY_OPTIONS_TYPE_L2TPV3:
1025             legacy.type = NET_CLIENT_DRIVER_L2TPV3;
1026             legacy.u.l2tpv3 = opts->u.l2tpv3;
1027             break;
1028         case NET_LEGACY_OPTIONS_TYPE_SOCKET:
1029             legacy.type = NET_CLIENT_DRIVER_SOCKET;
1030             legacy.u.socket = opts->u.socket;
1031             break;
1032         case NET_LEGACY_OPTIONS_TYPE_VDE:
1033             legacy.type = NET_CLIENT_DRIVER_VDE;
1034             legacy.u.vde = opts->u.vde;
1035             break;
1036         case NET_LEGACY_OPTIONS_TYPE_DUMP:
1037             legacy.type = NET_CLIENT_DRIVER_DUMP;
1038             legacy.u.dump = opts->u.dump;
1039             break;
1040         case NET_LEGACY_OPTIONS_TYPE_BRIDGE:
1041             legacy.type = NET_CLIENT_DRIVER_BRIDGE;
1042             legacy.u.bridge = opts->u.bridge;
1043             break;
1044         case NET_LEGACY_OPTIONS_TYPE_NETMAP:
1045             legacy.type = NET_CLIENT_DRIVER_NETMAP;
1046             legacy.u.netmap = opts->u.netmap;
1047             break;
1048         case NET_LEGACY_OPTIONS_TYPE_VHOST_USER:
1049             legacy.type = NET_CLIENT_DRIVER_VHOST_USER;
1050             legacy.u.vhost_user = opts->u.vhost_user;
1051             break;
1052         default:
1053             abort();
1054         }
1055 
1056         if (!net_client_init_fun[netdev->type]) {
1057             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
1058                        "a net backend type (maybe it is not compiled "
1059                        "into this binary)");
1060             return -1;
1061         }
1062 
1063         /* Do not add to a vlan if it's a nic with a netdev= parameter. */
1064         if (netdev->type != NET_CLIENT_DRIVER_NIC ||
1065             !opts->u.nic.has_netdev) {
1066             peer = net_hub_add_port(net->has_vlan ? net->vlan : 0, NULL);
1067         }
1068 
1069         if (net->has_vlan && !vlan_warned) {
1070             error_report("'vlan' is deprecated. Please use 'netdev' instead.");
1071             vlan_warned = true;
1072         }
1073     }
1074 
1075     if (net_client_init_fun[netdev->type](netdev, name, peer, errp) < 0) {
1076         /* FIXME drop when all init functions store an Error */
1077         if (errp && !*errp) {
1078             error_setg(errp, QERR_DEVICE_INIT_FAILED,
1079                        NetClientDriver_str(netdev->type));
1080         }
1081         return -1;
1082     }
1083     return 0;
1084 }
1085 
1086 
1087 int net_client_init(QemuOpts *opts, bool is_netdev, Error **errp)
1088 {
1089     void *object = NULL;
1090     Error *err = NULL;
1091     int ret = -1;
1092     Visitor *v = opts_visitor_new(opts);
1093 
1094     {
1095         /* Parse convenience option format ip6-net=fec0::0[/64] */
1096         const char *ip6_net = qemu_opt_get(opts, "ipv6-net");
1097 
1098         if (ip6_net) {
1099             char buf[strlen(ip6_net) + 1];
1100 
1101             if (get_str_sep(buf, sizeof(buf), &ip6_net, '/') < 0) {
1102                 /* Default 64bit prefix length.  */
1103                 qemu_opt_set(opts, "ipv6-prefix", ip6_net, &error_abort);
1104                 qemu_opt_set_number(opts, "ipv6-prefixlen", 64, &error_abort);
1105             } else {
1106                 /* User-specified prefix length.  */
1107                 unsigned long len;
1108                 int err;
1109 
1110                 qemu_opt_set(opts, "ipv6-prefix", buf, &error_abort);
1111                 err = qemu_strtoul(ip6_net, NULL, 10, &len);
1112 
1113                 if (err) {
1114                     error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1115                               "ipv6-prefix", "a number");
1116                 } else {
1117                     qemu_opt_set_number(opts, "ipv6-prefixlen", len,
1118                                         &error_abort);
1119                 }
1120             }
1121             qemu_opt_unset(opts, "ipv6-net");
1122         }
1123     }
1124 
1125     if (is_netdev) {
1126         visit_type_Netdev(v, NULL, (Netdev **)&object, &err);
1127     } else {
1128         visit_type_NetLegacy(v, NULL, (NetLegacy **)&object, &err);
1129     }
1130 
1131     if (!err) {
1132         ret = net_client_init1(object, is_netdev, &err);
1133     }
1134 
1135     if (is_netdev) {
1136         qapi_free_Netdev(object);
1137     } else {
1138         qapi_free_NetLegacy(object);
1139     }
1140 
1141     error_propagate(errp, err);
1142     visit_free(v);
1143     return ret;
1144 }
1145 
1146 
1147 static int net_host_check_device(const char *device)
1148 {
1149     int i;
1150     for (i = 0; host_net_devices[i]; i++) {
1151         if (!strncmp(host_net_devices[i], device,
1152                      strlen(host_net_devices[i]))) {
1153             return 1;
1154         }
1155     }
1156 
1157     return 0;
1158 }
1159 
1160 void hmp_host_net_add(Monitor *mon, const QDict *qdict)
1161 {
1162     const char *device = qdict_get_str(qdict, "device");
1163     const char *opts_str = qdict_get_try_str(qdict, "opts");
1164     Error *local_err = NULL;
1165     QemuOpts *opts;
1166     static bool warned;
1167 
1168     if (!warned && !qtest_enabled()) {
1169         error_report("host_net_add is deprecated, use netdev_add instead");
1170         warned = true;
1171     }
1172 
1173     if (!net_host_check_device(device)) {
1174         monitor_printf(mon, "invalid host network device %s\n", device);
1175         return;
1176     }
1177 
1178     opts = qemu_opts_parse_noisily(qemu_find_opts("net"),
1179                                    opts_str ? opts_str : "", false);
1180     if (!opts) {
1181         return;
1182     }
1183 
1184     qemu_opt_set(opts, "type", device, &error_abort);
1185 
1186     net_client_init(opts, false, &local_err);
1187     if (local_err) {
1188         error_report_err(local_err);
1189         monitor_printf(mon, "adding host network device %s failed\n", device);
1190     }
1191 }
1192 
1193 void hmp_host_net_remove(Monitor *mon, const QDict *qdict)
1194 {
1195     NetClientState *nc;
1196     int vlan_id = qdict_get_int(qdict, "vlan_id");
1197     const char *device = qdict_get_str(qdict, "device");
1198     static bool warned;
1199 
1200     if (!warned && !qtest_enabled()) {
1201         error_report("host_net_remove is deprecated, use netdev_del instead");
1202         warned = true;
1203     }
1204 
1205     nc = net_hub_find_client_by_name(vlan_id, device);
1206     if (!nc) {
1207         error_report("Host network device '%s' on hub '%d' not found",
1208                      device, vlan_id);
1209         return;
1210     }
1211     if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
1212         error_report("invalid host network device '%s'", device);
1213         return;
1214     }
1215 
1216     qemu_del_net_client(nc->peer);
1217     qemu_del_net_client(nc);
1218     qemu_opts_del(qemu_opts_find(qemu_find_opts("net"), device));
1219 }
1220 
1221 void netdev_add(QemuOpts *opts, Error **errp)
1222 {
1223     net_client_init(opts, true, errp);
1224 }
1225 
1226 void qmp_netdev_add(QDict *qdict, QObject **ret, Error **errp)
1227 {
1228     Error *local_err = NULL;
1229     QemuOptsList *opts_list;
1230     QemuOpts *opts;
1231 
1232     opts_list = qemu_find_opts_err("netdev", &local_err);
1233     if (local_err) {
1234         goto out;
1235     }
1236 
1237     opts = qemu_opts_from_qdict(opts_list, qdict, &local_err);
1238     if (local_err) {
1239         goto out;
1240     }
1241 
1242     netdev_add(opts, &local_err);
1243     if (local_err) {
1244         qemu_opts_del(opts);
1245         goto out;
1246     }
1247 
1248 out:
1249     error_propagate(errp, local_err);
1250 }
1251 
1252 void qmp_netdev_del(const char *id, Error **errp)
1253 {
1254     NetClientState *nc;
1255     QemuOpts *opts;
1256 
1257     nc = qemu_find_netdev(id);
1258     if (!nc) {
1259         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1260                   "Device '%s' not found", id);
1261         return;
1262     }
1263 
1264     opts = qemu_opts_find(qemu_find_opts_err("netdev", NULL), id);
1265     if (!opts) {
1266         error_setg(errp, "Device '%s' is not a netdev", id);
1267         return;
1268     }
1269 
1270     qemu_del_net_client(nc);
1271     qemu_opts_del(opts);
1272 }
1273 
1274 static void netfilter_print_info(Monitor *mon, NetFilterState *nf)
1275 {
1276     char *str;
1277     ObjectProperty *prop;
1278     ObjectPropertyIterator iter;
1279     Visitor *v;
1280 
1281     /* generate info str */
1282     object_property_iter_init(&iter, OBJECT(nf));
1283     while ((prop = object_property_iter_next(&iter))) {
1284         if (!strcmp(prop->name, "type")) {
1285             continue;
1286         }
1287         v = string_output_visitor_new(false, &str);
1288         object_property_get(OBJECT(nf), v, prop->name, NULL);
1289         visit_complete(v, &str);
1290         visit_free(v);
1291         monitor_printf(mon, ",%s=%s", prop->name, str);
1292         g_free(str);
1293     }
1294     monitor_printf(mon, "\n");
1295 }
1296 
1297 void print_net_client(Monitor *mon, NetClientState *nc)
1298 {
1299     NetFilterState *nf;
1300 
1301     monitor_printf(mon, "%s: index=%d,type=%s,%s\n", nc->name,
1302                    nc->queue_index,
1303                    NetClientDriver_str(nc->info->type),
1304                    nc->info_str);
1305     if (!QTAILQ_EMPTY(&nc->filters)) {
1306         monitor_printf(mon, "filters:\n");
1307     }
1308     QTAILQ_FOREACH(nf, &nc->filters, next) {
1309         char *path = object_get_canonical_path_component(OBJECT(nf));
1310 
1311         monitor_printf(mon, "  - %s: type=%s", path,
1312                        object_get_typename(OBJECT(nf)));
1313         netfilter_print_info(mon, nf);
1314         g_free(path);
1315     }
1316 }
1317 
1318 RxFilterInfoList *qmp_query_rx_filter(bool has_name, const char *name,
1319                                       Error **errp)
1320 {
1321     NetClientState *nc;
1322     RxFilterInfoList *filter_list = NULL, *last_entry = NULL;
1323 
1324     QTAILQ_FOREACH(nc, &net_clients, next) {
1325         RxFilterInfoList *entry;
1326         RxFilterInfo *info;
1327 
1328         if (has_name && strcmp(nc->name, name) != 0) {
1329             continue;
1330         }
1331 
1332         /* only query rx-filter information of NIC */
1333         if (nc->info->type != NET_CLIENT_DRIVER_NIC) {
1334             if (has_name) {
1335                 error_setg(errp, "net client(%s) isn't a NIC", name);
1336                 return NULL;
1337             }
1338             continue;
1339         }
1340 
1341         /* only query information on queue 0 since the info is per nic,
1342          * not per queue
1343          */
1344         if (nc->queue_index != 0)
1345             continue;
1346 
1347         if (nc->info->query_rx_filter) {
1348             info = nc->info->query_rx_filter(nc);
1349             entry = g_malloc0(sizeof(*entry));
1350             entry->value = info;
1351 
1352             if (!filter_list) {
1353                 filter_list = entry;
1354             } else {
1355                 last_entry->next = entry;
1356             }
1357             last_entry = entry;
1358         } else if (has_name) {
1359             error_setg(errp, "net client(%s) doesn't support"
1360                        " rx-filter querying", name);
1361             return NULL;
1362         }
1363 
1364         if (has_name) {
1365             break;
1366         }
1367     }
1368 
1369     if (filter_list == NULL && has_name) {
1370         error_setg(errp, "invalid net client name: %s", name);
1371     }
1372 
1373     return filter_list;
1374 }
1375 
1376 void hmp_info_network(Monitor *mon, const QDict *qdict)
1377 {
1378     NetClientState *nc, *peer;
1379     NetClientDriver type;
1380 
1381     net_hub_info(mon);
1382 
1383     QTAILQ_FOREACH(nc, &net_clients, next) {
1384         peer = nc->peer;
1385         type = nc->info->type;
1386 
1387         /* Skip if already printed in hub info */
1388         if (net_hub_id_for_client(nc, NULL) == 0) {
1389             continue;
1390         }
1391 
1392         if (!peer || type == NET_CLIENT_DRIVER_NIC) {
1393             print_net_client(mon, nc);
1394         } /* else it's a netdev connected to a NIC, printed with the NIC */
1395         if (peer && type == NET_CLIENT_DRIVER_NIC) {
1396             monitor_printf(mon, " \\ ");
1397             print_net_client(mon, peer);
1398         }
1399     }
1400 }
1401 
1402 void qmp_set_link(const char *name, bool up, Error **errp)
1403 {
1404     NetClientState *ncs[MAX_QUEUE_NUM];
1405     NetClientState *nc;
1406     int queues, i;
1407 
1408     queues = qemu_find_net_clients_except(name, ncs,
1409                                           NET_CLIENT_DRIVER__MAX,
1410                                           MAX_QUEUE_NUM);
1411 
1412     if (queues == 0) {
1413         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1414                   "Device '%s' not found", name);
1415         return;
1416     }
1417     nc = ncs[0];
1418 
1419     for (i = 0; i < queues; i++) {
1420         ncs[i]->link_down = !up;
1421     }
1422 
1423     if (nc->info->link_status_changed) {
1424         nc->info->link_status_changed(nc);
1425     }
1426 
1427     if (nc->peer) {
1428         /* Change peer link only if the peer is NIC and then notify peer.
1429          * If the peer is a HUBPORT or a backend, we do not change the
1430          * link status.
1431          *
1432          * This behavior is compatible with qemu vlans where there could be
1433          * multiple clients that can still communicate with each other in
1434          * disconnected mode. For now maintain this compatibility.
1435          */
1436         if (nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
1437             for (i = 0; i < queues; i++) {
1438                 ncs[i]->peer->link_down = !up;
1439             }
1440         }
1441         if (nc->peer->info->link_status_changed) {
1442             nc->peer->info->link_status_changed(nc->peer);
1443         }
1444     }
1445 }
1446 
1447 static void net_vm_change_state_handler(void *opaque, int running,
1448                                         RunState state)
1449 {
1450     NetClientState *nc;
1451     NetClientState *tmp;
1452 
1453     QTAILQ_FOREACH_SAFE(nc, &net_clients, next, tmp) {
1454         if (running) {
1455             /* Flush queued packets and wake up backends. */
1456             if (nc->peer && qemu_can_send_packet(nc)) {
1457                 qemu_flush_queued_packets(nc->peer);
1458             }
1459         } else {
1460             /* Complete all queued packets, to guarantee we don't modify
1461              * state later when VM is not running.
1462              */
1463             qemu_flush_or_purge_queued_packets(nc, true);
1464         }
1465     }
1466 }
1467 
1468 void net_cleanup(void)
1469 {
1470     NetClientState *nc;
1471 
1472     /* We may del multiple entries during qemu_del_net_client(),
1473      * so QTAILQ_FOREACH_SAFE() is also not safe here.
1474      */
1475     while (!QTAILQ_EMPTY(&net_clients)) {
1476         nc = QTAILQ_FIRST(&net_clients);
1477         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
1478             qemu_del_nic(qemu_get_nic(nc));
1479         } else {
1480             qemu_del_net_client(nc);
1481         }
1482     }
1483 
1484     qemu_del_vm_change_state_handler(net_change_state_entry);
1485 }
1486 
1487 void net_check_clients(void)
1488 {
1489     NetClientState *nc;
1490     int i;
1491 
1492     net_hub_check_clients();
1493 
1494     QTAILQ_FOREACH(nc, &net_clients, next) {
1495         if (!nc->peer) {
1496             fprintf(stderr, "Warning: %s %s has no peer\n",
1497                     nc->info->type == NET_CLIENT_DRIVER_NIC ?
1498                     "nic" : "netdev", nc->name);
1499         }
1500     }
1501 
1502     /* Check that all NICs requested via -net nic actually got created.
1503      * NICs created via -device don't need to be checked here because
1504      * they are always instantiated.
1505      */
1506     for (i = 0; i < MAX_NICS; i++) {
1507         NICInfo *nd = &nd_table[i];
1508         if (nd->used && !nd->instantiated) {
1509             fprintf(stderr, "Warning: requested NIC (%s, model %s) "
1510                     "was not created (not supported by this machine?)\n",
1511                     nd->name ? nd->name : "anonymous",
1512                     nd->model ? nd->model : "unspecified");
1513         }
1514     }
1515 }
1516 
1517 static int net_init_client(void *dummy, QemuOpts *opts, Error **errp)
1518 {
1519     Error *local_err = NULL;
1520 
1521     net_client_init(opts, false, &local_err);
1522     if (local_err) {
1523         error_report_err(local_err);
1524         return -1;
1525     }
1526 
1527     return 0;
1528 }
1529 
1530 static int net_init_netdev(void *dummy, QemuOpts *opts, Error **errp)
1531 {
1532     Error *local_err = NULL;
1533     int ret;
1534 
1535     ret = net_client_init(opts, true, &local_err);
1536     if (local_err) {
1537         error_report_err(local_err);
1538         return -1;
1539     }
1540 
1541     return ret;
1542 }
1543 
1544 int net_init_clients(void)
1545 {
1546     QemuOptsList *net = qemu_find_opts("net");
1547 
1548     net_change_state_entry =
1549         qemu_add_vm_change_state_handler(net_vm_change_state_handler, NULL);
1550 
1551     QTAILQ_INIT(&net_clients);
1552 
1553     if (qemu_opts_foreach(qemu_find_opts("netdev"),
1554                           net_init_netdev, NULL, NULL)) {
1555         return -1;
1556     }
1557 
1558     if (qemu_opts_foreach(net, net_init_client, NULL, NULL)) {
1559         return -1;
1560     }
1561 
1562     return 0;
1563 }
1564 
1565 int net_client_parse(QemuOptsList *opts_list, const char *optarg)
1566 {
1567 #if defined(CONFIG_SLIRP)
1568     int ret;
1569     if (net_slirp_parse_legacy(opts_list, optarg, &ret)) {
1570         return ret;
1571     }
1572 #endif
1573 
1574     if (!qemu_opts_parse_noisily(opts_list, optarg, true)) {
1575         return -1;
1576     }
1577 
1578     return 0;
1579 }
1580 
1581 /* From FreeBSD */
1582 /* XXX: optimize */
1583 unsigned compute_mcast_idx(const uint8_t *ep)
1584 {
1585     uint32_t crc;
1586     int carry, i, j;
1587     uint8_t b;
1588 
1589     crc = 0xffffffff;
1590     for (i = 0; i < 6; i++) {
1591         b = *ep++;
1592         for (j = 0; j < 8; j++) {
1593             carry = ((crc & 0x80000000L) ? 1 : 0) ^ (b & 0x01);
1594             crc <<= 1;
1595             b >>= 1;
1596             if (carry) {
1597                 crc = ((crc ^ POLYNOMIAL) | carry);
1598             }
1599         }
1600     }
1601     return crc >> 26;
1602 }
1603 
1604 QemuOptsList qemu_netdev_opts = {
1605     .name = "netdev",
1606     .implied_opt_name = "type",
1607     .head = QTAILQ_HEAD_INITIALIZER(qemu_netdev_opts.head),
1608     .desc = {
1609         /*
1610          * no elements => accept any params
1611          * validation will happen later
1612          */
1613         { /* end of list */ }
1614     },
1615 };
1616 
1617 QemuOptsList qemu_net_opts = {
1618     .name = "net",
1619     .implied_opt_name = "type",
1620     .head = QTAILQ_HEAD_INITIALIZER(qemu_net_opts.head),
1621     .desc = {
1622         /*
1623          * no elements => accept any params
1624          * validation will happen later
1625          */
1626         { /* end of list */ }
1627     },
1628 };
1629 
1630 void net_socket_rs_init(SocketReadState *rs,
1631                         SocketReadStateFinalize *finalize,
1632                         bool vnet_hdr)
1633 {
1634     rs->state = 0;
1635     rs->vnet_hdr = vnet_hdr;
1636     rs->index = 0;
1637     rs->packet_len = 0;
1638     rs->vnet_hdr_len = 0;
1639     memset(rs->buf, 0, sizeof(rs->buf));
1640     rs->finalize = finalize;
1641 }
1642 
1643 /*
1644  * Returns
1645  * 0: success
1646  * -1: error occurs
1647  */
1648 int net_fill_rstate(SocketReadState *rs, const uint8_t *buf, int size)
1649 {
1650     unsigned int l;
1651 
1652     while (size > 0) {
1653         /* Reassemble a packet from the network.
1654          * 0 = getting length.
1655          * 1 = getting vnet header length.
1656          * 2 = getting data.
1657          */
1658         switch (rs->state) {
1659         case 0:
1660             l = 4 - rs->index;
1661             if (l > size) {
1662                 l = size;
1663             }
1664             memcpy(rs->buf + rs->index, buf, l);
1665             buf += l;
1666             size -= l;
1667             rs->index += l;
1668             if (rs->index == 4) {
1669                 /* got length */
1670                 rs->packet_len = ntohl(*(uint32_t *)rs->buf);
1671                 rs->index = 0;
1672                 if (rs->vnet_hdr) {
1673                     rs->state = 1;
1674                 } else {
1675                     rs->state = 2;
1676                     rs->vnet_hdr_len = 0;
1677                 }
1678             }
1679             break;
1680         case 1:
1681             l = 4 - rs->index;
1682             if (l > size) {
1683                 l = size;
1684             }
1685             memcpy(rs->buf + rs->index, buf, l);
1686             buf += l;
1687             size -= l;
1688             rs->index += l;
1689             if (rs->index == 4) {
1690                 /* got vnet header length */
1691                 rs->vnet_hdr_len = ntohl(*(uint32_t *)rs->buf);
1692                 rs->index = 0;
1693                 rs->state = 2;
1694             }
1695             break;
1696         case 2:
1697             l = rs->packet_len - rs->index;
1698             if (l > size) {
1699                 l = size;
1700             }
1701             if (rs->index + l <= sizeof(rs->buf)) {
1702                 memcpy(rs->buf + rs->index, buf, l);
1703             } else {
1704                 fprintf(stderr, "serious error: oversized packet received,"
1705                     "connection terminated.\n");
1706                 rs->index = rs->state = 0;
1707                 return -1;
1708             }
1709 
1710             rs->index += l;
1711             buf += l;
1712             size -= l;
1713             if (rs->index >= rs->packet_len) {
1714                 rs->index = 0;
1715                 rs->state = 0;
1716                 assert(rs->finalize);
1717                 rs->finalize(rs);
1718             }
1719             break;
1720         }
1721     }
1722 
1723     assert(size == 0);
1724     return 0;
1725 }
1726