xref: /openbmc/qemu/net/net.c (revision ba632924)
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 
25 #include "qemu/osdep.h"
26 
27 #include "net/net.h"
28 #include "clients.h"
29 #include "hub.h"
30 #include "net/slirp.h"
31 #include "net/eth.h"
32 #include "util.h"
33 
34 #include "monitor/monitor.h"
35 #include "qemu/help_option.h"
36 #include "qapi/qapi-commands-net.h"
37 #include "qapi/qapi-visit-net.h"
38 #include "qapi/qmp/qdict.h"
39 #include "qapi/qmp/qerror.h"
40 #include "qemu/error-report.h"
41 #include "qemu/sockets.h"
42 #include "qemu/cutils.h"
43 #include "qemu/config-file.h"
44 #include "hw/qdev.h"
45 #include "qemu/iov.h"
46 #include "qemu/main-loop.h"
47 #include "qemu/option.h"
48 #include "qapi/error.h"
49 #include "qapi/opts-visitor.h"
50 #include "sysemu/sysemu.h"
51 #include "sysemu/qtest.h"
52 #include "net/filter.h"
53 #include "qapi/string-output-visitor.h"
54 
55 /* Net bridge is currently not supported for W32. */
56 #if !defined(_WIN32)
57 # define CONFIG_NET_BRIDGE
58 #endif
59 
60 static VMChangeStateEntry *net_change_state_entry;
61 static QTAILQ_HEAD(, NetClientState) net_clients;
62 
63 /***********************************************************/
64 /* network device redirectors */
65 
66 static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
67 {
68     const char *p, *p1;
69     int len;
70     p = *pp;
71     p1 = strchr(p, sep);
72     if (!p1)
73         return -1;
74     len = p1 - p;
75     p1++;
76     if (buf_size > 0) {
77         if (len > buf_size - 1)
78             len = buf_size - 1;
79         memcpy(buf, p, len);
80         buf[len] = '\0';
81     }
82     *pp = p1;
83     return 0;
84 }
85 
86 int parse_host_port(struct sockaddr_in *saddr, const char *str,
87                     Error **errp)
88 {
89     char buf[512];
90     struct hostent *he;
91     const char *p, *r;
92     int port;
93 
94     p = str;
95     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
96         error_setg(errp, "host address '%s' doesn't contain ':' "
97                    "separating host from port", str);
98         return -1;
99     }
100     saddr->sin_family = AF_INET;
101     if (buf[0] == '\0') {
102         saddr->sin_addr.s_addr = 0;
103     } else {
104         if (qemu_isdigit(buf[0])) {
105             if (!inet_aton(buf, &saddr->sin_addr)) {
106                 error_setg(errp, "host address '%s' is not a valid "
107                            "IPv4 address", buf);
108                 return -1;
109             }
110         } else {
111             he = gethostbyname(buf);
112             if (he == NULL) {
113                 error_setg(errp, "can't resolve host address '%s'", buf);
114                 return - 1;
115             }
116             saddr->sin_addr = *(struct in_addr *)he->h_addr;
117         }
118     }
119     port = strtol(p, (char **)&r, 0);
120     if (r == p) {
121         error_setg(errp, "port number '%s' is invalid", p);
122         return -1;
123     }
124     saddr->sin_port = htons(port);
125     return 0;
126 }
127 
128 char *qemu_mac_strdup_printf(const uint8_t *macaddr)
129 {
130     return g_strdup_printf("%.2x:%.2x:%.2x:%.2x:%.2x:%.2x",
131                            macaddr[0], macaddr[1], macaddr[2],
132                            macaddr[3], macaddr[4], macaddr[5]);
133 }
134 
135 void qemu_format_nic_info_str(NetClientState *nc, uint8_t macaddr[6])
136 {
137     snprintf(nc->info_str, sizeof(nc->info_str),
138              "model=%s,macaddr=%02x:%02x:%02x:%02x:%02x:%02x",
139              nc->model,
140              macaddr[0], macaddr[1], macaddr[2],
141              macaddr[3], macaddr[4], macaddr[5]);
142 }
143 
144 static int mac_table[256] = {0};
145 
146 static void qemu_macaddr_set_used(MACAddr *macaddr)
147 {
148     int index;
149 
150     for (index = 0x56; index < 0xFF; index++) {
151         if (macaddr->a[5] == index) {
152             mac_table[index]++;
153         }
154     }
155 }
156 
157 static void qemu_macaddr_set_free(MACAddr *macaddr)
158 {
159     int index;
160     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
161 
162     if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
163         return;
164     }
165     for (index = 0x56; index < 0xFF; index++) {
166         if (macaddr->a[5] == index) {
167             mac_table[index]--;
168         }
169     }
170 }
171 
172 static int qemu_macaddr_get_free(void)
173 {
174     int index;
175 
176     for (index = 0x56; index < 0xFF; index++) {
177         if (mac_table[index] == 0) {
178             return index;
179         }
180     }
181 
182     return -1;
183 }
184 
185 void qemu_macaddr_default_if_unset(MACAddr *macaddr)
186 {
187     static const MACAddr zero = { .a = { 0,0,0,0,0,0 } };
188     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
189 
190     if (memcmp(macaddr, &zero, sizeof(zero)) != 0) {
191         if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
192             return;
193         } else {
194             qemu_macaddr_set_used(macaddr);
195             return;
196         }
197     }
198 
199     macaddr->a[0] = 0x52;
200     macaddr->a[1] = 0x54;
201     macaddr->a[2] = 0x00;
202     macaddr->a[3] = 0x12;
203     macaddr->a[4] = 0x34;
204     macaddr->a[5] = qemu_macaddr_get_free();
205     qemu_macaddr_set_used(macaddr);
206 }
207 
208 /**
209  * Generate a name for net client
210  *
211  * Only net clients created with the legacy -net option and NICs need this.
212  */
213 static char *assign_name(NetClientState *nc1, const char *model)
214 {
215     NetClientState *nc;
216     int id = 0;
217 
218     QTAILQ_FOREACH(nc, &net_clients, next) {
219         if (nc == nc1) {
220             continue;
221         }
222         if (strcmp(nc->model, model) == 0) {
223             id++;
224         }
225     }
226 
227     return g_strdup_printf("%s.%d", model, id);
228 }
229 
230 static void qemu_net_client_destructor(NetClientState *nc)
231 {
232     g_free(nc);
233 }
234 static ssize_t qemu_deliver_packet_iov(NetClientState *sender,
235                                        unsigned flags,
236                                        const struct iovec *iov,
237                                        int iovcnt,
238                                        void *opaque);
239 
240 static void qemu_net_client_setup(NetClientState *nc,
241                                   NetClientInfo *info,
242                                   NetClientState *peer,
243                                   const char *model,
244                                   const char *name,
245                                   NetClientDestructor *destructor)
246 {
247     nc->info = info;
248     nc->model = g_strdup(model);
249     if (name) {
250         nc->name = g_strdup(name);
251     } else {
252         nc->name = assign_name(nc, model);
253     }
254 
255     if (peer) {
256         assert(!peer->peer);
257         nc->peer = peer;
258         peer->peer = nc;
259     }
260     QTAILQ_INSERT_TAIL(&net_clients, nc, next);
261 
262     nc->incoming_queue = qemu_new_net_queue(qemu_deliver_packet_iov, nc);
263     nc->destructor = destructor;
264     QTAILQ_INIT(&nc->filters);
265 }
266 
267 NetClientState *qemu_new_net_client(NetClientInfo *info,
268                                     NetClientState *peer,
269                                     const char *model,
270                                     const char *name)
271 {
272     NetClientState *nc;
273 
274     assert(info->size >= sizeof(NetClientState));
275 
276     nc = g_malloc0(info->size);
277     qemu_net_client_setup(nc, info, peer, model, name,
278                           qemu_net_client_destructor);
279 
280     return nc;
281 }
282 
283 NICState *qemu_new_nic(NetClientInfo *info,
284                        NICConf *conf,
285                        const char *model,
286                        const char *name,
287                        void *opaque)
288 {
289     NetClientState **peers = conf->peers.ncs;
290     NICState *nic;
291     int i, queues = MAX(1, conf->peers.queues);
292 
293     assert(info->type == NET_CLIENT_DRIVER_NIC);
294     assert(info->size >= sizeof(NICState));
295 
296     nic = g_malloc0(info->size + sizeof(NetClientState) * queues);
297     nic->ncs = (void *)nic + info->size;
298     nic->conf = conf;
299     nic->opaque = opaque;
300 
301     for (i = 0; i < queues; i++) {
302         qemu_net_client_setup(&nic->ncs[i], info, peers[i], model, name,
303                               NULL);
304         nic->ncs[i].queue_index = i;
305     }
306 
307     return nic;
308 }
309 
310 NetClientState *qemu_get_subqueue(NICState *nic, int queue_index)
311 {
312     return nic->ncs + queue_index;
313 }
314 
315 NetClientState *qemu_get_queue(NICState *nic)
316 {
317     return qemu_get_subqueue(nic, 0);
318 }
319 
320 NICState *qemu_get_nic(NetClientState *nc)
321 {
322     NetClientState *nc0 = nc - nc->queue_index;
323 
324     return (NICState *)((void *)nc0 - nc->info->size);
325 }
326 
327 void *qemu_get_nic_opaque(NetClientState *nc)
328 {
329     NICState *nic = qemu_get_nic(nc);
330 
331     return nic->opaque;
332 }
333 
334 static void qemu_cleanup_net_client(NetClientState *nc)
335 {
336     QTAILQ_REMOVE(&net_clients, nc, next);
337 
338     if (nc->info->cleanup) {
339         nc->info->cleanup(nc);
340     }
341 }
342 
343 static void qemu_free_net_client(NetClientState *nc)
344 {
345     if (nc->incoming_queue) {
346         qemu_del_net_queue(nc->incoming_queue);
347     }
348     if (nc->peer) {
349         nc->peer->peer = NULL;
350     }
351     g_free(nc->name);
352     g_free(nc->model);
353     if (nc->destructor) {
354         nc->destructor(nc);
355     }
356 }
357 
358 void qemu_del_net_client(NetClientState *nc)
359 {
360     NetClientState *ncs[MAX_QUEUE_NUM];
361     int queues, i;
362     NetFilterState *nf, *next;
363 
364     assert(nc->info->type != NET_CLIENT_DRIVER_NIC);
365 
366     /* If the NetClientState belongs to a multiqueue backend, we will change all
367      * other NetClientStates also.
368      */
369     queues = qemu_find_net_clients_except(nc->name, ncs,
370                                           NET_CLIENT_DRIVER_NIC,
371                                           MAX_QUEUE_NUM);
372     assert(queues != 0);
373 
374     QTAILQ_FOREACH_SAFE(nf, &nc->filters, next, next) {
375         object_unparent(OBJECT(nf));
376     }
377 
378     /* If there is a peer NIC, delete and cleanup client, but do not free. */
379     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
380         NICState *nic = qemu_get_nic(nc->peer);
381         if (nic->peer_deleted) {
382             return;
383         }
384         nic->peer_deleted = true;
385 
386         for (i = 0; i < queues; i++) {
387             ncs[i]->peer->link_down = true;
388         }
389 
390         if (nc->peer->info->link_status_changed) {
391             nc->peer->info->link_status_changed(nc->peer);
392         }
393 
394         for (i = 0; i < queues; i++) {
395             qemu_cleanup_net_client(ncs[i]);
396         }
397 
398         return;
399     }
400 
401     for (i = 0; i < queues; i++) {
402         qemu_cleanup_net_client(ncs[i]);
403         qemu_free_net_client(ncs[i]);
404     }
405 }
406 
407 void qemu_del_nic(NICState *nic)
408 {
409     int i, queues = MAX(nic->conf->peers.queues, 1);
410 
411     qemu_macaddr_set_free(&nic->conf->macaddr);
412 
413     /* If this is a peer NIC and peer has already been deleted, free it now. */
414     if (nic->peer_deleted) {
415         for (i = 0; i < queues; i++) {
416             qemu_free_net_client(qemu_get_subqueue(nic, i)->peer);
417         }
418     }
419 
420     for (i = queues - 1; i >= 0; i--) {
421         NetClientState *nc = qemu_get_subqueue(nic, i);
422 
423         qemu_cleanup_net_client(nc);
424         qemu_free_net_client(nc);
425     }
426 
427     g_free(nic);
428 }
429 
430 void qemu_foreach_nic(qemu_nic_foreach func, void *opaque)
431 {
432     NetClientState *nc;
433 
434     QTAILQ_FOREACH(nc, &net_clients, next) {
435         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
436             if (nc->queue_index == 0) {
437                 func(qemu_get_nic(nc), opaque);
438             }
439         }
440     }
441 }
442 
443 bool qemu_has_ufo(NetClientState *nc)
444 {
445     if (!nc || !nc->info->has_ufo) {
446         return false;
447     }
448 
449     return nc->info->has_ufo(nc);
450 }
451 
452 bool qemu_has_vnet_hdr(NetClientState *nc)
453 {
454     if (!nc || !nc->info->has_vnet_hdr) {
455         return false;
456     }
457 
458     return nc->info->has_vnet_hdr(nc);
459 }
460 
461 bool qemu_has_vnet_hdr_len(NetClientState *nc, int len)
462 {
463     if (!nc || !nc->info->has_vnet_hdr_len) {
464         return false;
465     }
466 
467     return nc->info->has_vnet_hdr_len(nc, len);
468 }
469 
470 void qemu_using_vnet_hdr(NetClientState *nc, bool enable)
471 {
472     if (!nc || !nc->info->using_vnet_hdr) {
473         return;
474     }
475 
476     nc->info->using_vnet_hdr(nc, enable);
477 }
478 
479 void qemu_set_offload(NetClientState *nc, int csum, int tso4, int tso6,
480                           int ecn, int ufo)
481 {
482     if (!nc || !nc->info->set_offload) {
483         return;
484     }
485 
486     nc->info->set_offload(nc, csum, tso4, tso6, ecn, ufo);
487 }
488 
489 void qemu_set_vnet_hdr_len(NetClientState *nc, int len)
490 {
491     if (!nc || !nc->info->set_vnet_hdr_len) {
492         return;
493     }
494 
495     nc->vnet_hdr_len = len;
496     nc->info->set_vnet_hdr_len(nc, len);
497 }
498 
499 int qemu_set_vnet_le(NetClientState *nc, bool is_le)
500 {
501 #ifdef HOST_WORDS_BIGENDIAN
502     if (!nc || !nc->info->set_vnet_le) {
503         return -ENOSYS;
504     }
505 
506     return nc->info->set_vnet_le(nc, is_le);
507 #else
508     return 0;
509 #endif
510 }
511 
512 int qemu_set_vnet_be(NetClientState *nc, bool is_be)
513 {
514 #ifdef HOST_WORDS_BIGENDIAN
515     return 0;
516 #else
517     if (!nc || !nc->info->set_vnet_be) {
518         return -ENOSYS;
519     }
520 
521     return nc->info->set_vnet_be(nc, is_be);
522 #endif
523 }
524 
525 int qemu_can_send_packet(NetClientState *sender)
526 {
527     int vm_running = runstate_is_running();
528 
529     if (!vm_running) {
530         return 0;
531     }
532 
533     if (!sender->peer) {
534         return 1;
535     }
536 
537     if (sender->peer->receive_disabled) {
538         return 0;
539     } else if (sender->peer->info->can_receive &&
540                !sender->peer->info->can_receive(sender->peer)) {
541         return 0;
542     }
543     return 1;
544 }
545 
546 static ssize_t filter_receive_iov(NetClientState *nc,
547                                   NetFilterDirection direction,
548                                   NetClientState *sender,
549                                   unsigned flags,
550                                   const struct iovec *iov,
551                                   int iovcnt,
552                                   NetPacketSent *sent_cb)
553 {
554     ssize_t ret = 0;
555     NetFilterState *nf = NULL;
556 
557     if (direction == NET_FILTER_DIRECTION_TX) {
558         QTAILQ_FOREACH(nf, &nc->filters, next) {
559             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
560                                          iovcnt, sent_cb);
561             if (ret) {
562                 return ret;
563             }
564         }
565     } else {
566         QTAILQ_FOREACH_REVERSE(nf, &nc->filters, next) {
567             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
568                                          iovcnt, sent_cb);
569             if (ret) {
570                 return ret;
571             }
572         }
573     }
574 
575     return ret;
576 }
577 
578 static ssize_t filter_receive(NetClientState *nc,
579                               NetFilterDirection direction,
580                               NetClientState *sender,
581                               unsigned flags,
582                               const uint8_t *data,
583                               size_t size,
584                               NetPacketSent *sent_cb)
585 {
586     struct iovec iov = {
587         .iov_base = (void *)data,
588         .iov_len = size
589     };
590 
591     return filter_receive_iov(nc, direction, sender, flags, &iov, 1, sent_cb);
592 }
593 
594 void qemu_purge_queued_packets(NetClientState *nc)
595 {
596     if (!nc->peer) {
597         return;
598     }
599 
600     qemu_net_queue_purge(nc->peer->incoming_queue, nc);
601 }
602 
603 void qemu_flush_or_purge_queued_packets(NetClientState *nc, bool purge)
604 {
605     nc->receive_disabled = 0;
606 
607     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_HUBPORT) {
608         if (net_hub_flush(nc->peer)) {
609             qemu_notify_event();
610         }
611     }
612     if (qemu_net_queue_flush(nc->incoming_queue)) {
613         /* We emptied the queue successfully, signal to the IO thread to repoll
614          * the file descriptor (for tap, for example).
615          */
616         qemu_notify_event();
617     } else if (purge) {
618         /* Unable to empty the queue, purge remaining packets */
619         qemu_net_queue_purge(nc->incoming_queue, nc);
620     }
621 }
622 
623 void qemu_flush_queued_packets(NetClientState *nc)
624 {
625     qemu_flush_or_purge_queued_packets(nc, false);
626 }
627 
628 static ssize_t qemu_send_packet_async_with_flags(NetClientState *sender,
629                                                  unsigned flags,
630                                                  const uint8_t *buf, int size,
631                                                  NetPacketSent *sent_cb)
632 {
633     NetQueue *queue;
634     int ret;
635 
636 #ifdef DEBUG_NET
637     printf("qemu_send_packet_async:\n");
638     qemu_hexdump((const char *)buf, stdout, "net", size);
639 #endif
640 
641     if (sender->link_down || !sender->peer) {
642         return size;
643     }
644 
645     /* Let filters handle the packet first */
646     ret = filter_receive(sender, NET_FILTER_DIRECTION_TX,
647                          sender, flags, buf, size, sent_cb);
648     if (ret) {
649         return ret;
650     }
651 
652     ret = filter_receive(sender->peer, NET_FILTER_DIRECTION_RX,
653                          sender, flags, buf, size, sent_cb);
654     if (ret) {
655         return ret;
656     }
657 
658     queue = sender->peer->incoming_queue;
659 
660     return qemu_net_queue_send(queue, sender, flags, buf, size, sent_cb);
661 }
662 
663 ssize_t qemu_send_packet_async(NetClientState *sender,
664                                const uint8_t *buf, int size,
665                                NetPacketSent *sent_cb)
666 {
667     return qemu_send_packet_async_with_flags(sender, QEMU_NET_PACKET_FLAG_NONE,
668                                              buf, size, sent_cb);
669 }
670 
671 ssize_t qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size)
672 {
673     return qemu_send_packet_async(nc, buf, size, NULL);
674 }
675 
676 ssize_t qemu_send_packet_raw(NetClientState *nc, const uint8_t *buf, int size)
677 {
678     return qemu_send_packet_async_with_flags(nc, QEMU_NET_PACKET_FLAG_RAW,
679                                              buf, size, NULL);
680 }
681 
682 static ssize_t nc_sendv_compat(NetClientState *nc, const struct iovec *iov,
683                                int iovcnt, unsigned flags)
684 {
685     uint8_t *buf = NULL;
686     uint8_t *buffer;
687     size_t offset;
688     ssize_t ret;
689 
690     if (iovcnt == 1) {
691         buffer = iov[0].iov_base;
692         offset = iov[0].iov_len;
693     } else {
694         offset = iov_size(iov, iovcnt);
695         if (offset > NET_BUFSIZE) {
696             return -1;
697         }
698         buf = g_malloc(offset);
699         buffer = buf;
700         offset = iov_to_buf(iov, iovcnt, 0, buf, offset);
701     }
702 
703     if (flags & QEMU_NET_PACKET_FLAG_RAW && nc->info->receive_raw) {
704         ret = nc->info->receive_raw(nc, buffer, offset);
705     } else {
706         ret = nc->info->receive(nc, buffer, offset);
707     }
708 
709     g_free(buf);
710     return ret;
711 }
712 
713 static ssize_t qemu_deliver_packet_iov(NetClientState *sender,
714                                        unsigned flags,
715                                        const struct iovec *iov,
716                                        int iovcnt,
717                                        void *opaque)
718 {
719     NetClientState *nc = opaque;
720     int ret;
721 
722 
723     if (nc->link_down) {
724         return iov_size(iov, iovcnt);
725     }
726 
727     if (nc->receive_disabled) {
728         return 0;
729     }
730 
731     if (nc->info->receive_iov && !(flags & QEMU_NET_PACKET_FLAG_RAW)) {
732         ret = nc->info->receive_iov(nc, iov, iovcnt);
733     } else {
734         ret = nc_sendv_compat(nc, iov, iovcnt, flags);
735     }
736 
737     if (ret == 0) {
738         nc->receive_disabled = 1;
739     }
740 
741     return ret;
742 }
743 
744 ssize_t qemu_sendv_packet_async(NetClientState *sender,
745                                 const struct iovec *iov, int iovcnt,
746                                 NetPacketSent *sent_cb)
747 {
748     NetQueue *queue;
749     size_t size = iov_size(iov, iovcnt);
750     int ret;
751 
752     if (size > NET_BUFSIZE) {
753         return size;
754     }
755 
756     if (sender->link_down || !sender->peer) {
757         return size;
758     }
759 
760     /* Let filters handle the packet first */
761     ret = filter_receive_iov(sender, NET_FILTER_DIRECTION_TX, sender,
762                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
763     if (ret) {
764         return ret;
765     }
766 
767     ret = filter_receive_iov(sender->peer, NET_FILTER_DIRECTION_RX, sender,
768                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
769     if (ret) {
770         return ret;
771     }
772 
773     queue = sender->peer->incoming_queue;
774 
775     return qemu_net_queue_send_iov(queue, sender,
776                                    QEMU_NET_PACKET_FLAG_NONE,
777                                    iov, iovcnt, sent_cb);
778 }
779 
780 ssize_t
781 qemu_sendv_packet(NetClientState *nc, const struct iovec *iov, int iovcnt)
782 {
783     return qemu_sendv_packet_async(nc, iov, iovcnt, NULL);
784 }
785 
786 NetClientState *qemu_find_netdev(const char *id)
787 {
788     NetClientState *nc;
789 
790     QTAILQ_FOREACH(nc, &net_clients, next) {
791         if (nc->info->type == NET_CLIENT_DRIVER_NIC)
792             continue;
793         if (!strcmp(nc->name, id)) {
794             return nc;
795         }
796     }
797 
798     return NULL;
799 }
800 
801 int qemu_find_net_clients_except(const char *id, NetClientState **ncs,
802                                  NetClientDriver type, int max)
803 {
804     NetClientState *nc;
805     int ret = 0;
806 
807     QTAILQ_FOREACH(nc, &net_clients, next) {
808         if (nc->info->type == type) {
809             continue;
810         }
811         if (!id || !strcmp(nc->name, id)) {
812             if (ret < max) {
813                 ncs[ret] = nc;
814             }
815             ret++;
816         }
817     }
818 
819     return ret;
820 }
821 
822 static int nic_get_free_idx(void)
823 {
824     int index;
825 
826     for (index = 0; index < MAX_NICS; index++)
827         if (!nd_table[index].used)
828             return index;
829     return -1;
830 }
831 
832 int qemu_show_nic_models(const char *arg, const char *const *models)
833 {
834     int i;
835 
836     if (!arg || !is_help_option(arg)) {
837         return 0;
838     }
839 
840     fprintf(stderr, "qemu: Supported NIC models: ");
841     for (i = 0 ; models[i]; i++)
842         fprintf(stderr, "%s%c", models[i], models[i+1] ? ',' : '\n');
843     return 1;
844 }
845 
846 void qemu_check_nic_model(NICInfo *nd, const char *model)
847 {
848     const char *models[2];
849 
850     models[0] = model;
851     models[1] = NULL;
852 
853     if (qemu_show_nic_models(nd->model, models))
854         exit(0);
855     if (qemu_find_nic_model(nd, models, model) < 0)
856         exit(1);
857 }
858 
859 int qemu_find_nic_model(NICInfo *nd, const char * const *models,
860                         const char *default_model)
861 {
862     int i;
863 
864     if (!nd->model)
865         nd->model = g_strdup(default_model);
866 
867     for (i = 0 ; models[i]; i++) {
868         if (strcmp(nd->model, models[i]) == 0)
869             return i;
870     }
871 
872     error_report("Unsupported NIC model: %s", nd->model);
873     return -1;
874 }
875 
876 static int net_init_nic(const Netdev *netdev, const char *name,
877                         NetClientState *peer, Error **errp)
878 {
879     int idx;
880     NICInfo *nd;
881     const NetLegacyNicOptions *nic;
882 
883     assert(netdev->type == NET_CLIENT_DRIVER_NIC);
884     nic = &netdev->u.nic;
885 
886     idx = nic_get_free_idx();
887     if (idx == -1 || nb_nics >= MAX_NICS) {
888         error_setg(errp, "too many NICs");
889         return -1;
890     }
891 
892     nd = &nd_table[idx];
893 
894     memset(nd, 0, sizeof(*nd));
895 
896     if (nic->has_netdev) {
897         nd->netdev = qemu_find_netdev(nic->netdev);
898         if (!nd->netdev) {
899             error_setg(errp, "netdev '%s' not found", nic->netdev);
900             return -1;
901         }
902     } else {
903         assert(peer);
904         nd->netdev = peer;
905     }
906     nd->name = g_strdup(name);
907     if (nic->has_model) {
908         nd->model = g_strdup(nic->model);
909     }
910     if (nic->has_addr) {
911         nd->devaddr = g_strdup(nic->addr);
912     }
913 
914     if (nic->has_macaddr &&
915         net_parse_macaddr(nd->macaddr.a, nic->macaddr) < 0) {
916         error_setg(errp, "invalid syntax for ethernet address");
917         return -1;
918     }
919     if (nic->has_macaddr &&
920         is_multicast_ether_addr(nd->macaddr.a)) {
921         error_setg(errp,
922                    "NIC cannot have multicast MAC address (odd 1st byte)");
923         return -1;
924     }
925     qemu_macaddr_default_if_unset(&nd->macaddr);
926 
927     if (nic->has_vectors) {
928         if (nic->vectors > 0x7ffffff) {
929             error_setg(errp, "invalid # of vectors: %"PRIu32, nic->vectors);
930             return -1;
931         }
932         nd->nvectors = nic->vectors;
933     } else {
934         nd->nvectors = DEV_NVECTORS_UNSPECIFIED;
935     }
936 
937     nd->used = 1;
938     nb_nics++;
939 
940     return idx;
941 }
942 
943 
944 static int (* const net_client_init_fun[NET_CLIENT_DRIVER__MAX])(
945     const Netdev *netdev,
946     const char *name,
947     NetClientState *peer, Error **errp) = {
948         [NET_CLIENT_DRIVER_NIC]       = net_init_nic,
949 #ifdef CONFIG_SLIRP
950         [NET_CLIENT_DRIVER_USER]      = net_init_slirp,
951 #endif
952         [NET_CLIENT_DRIVER_TAP]       = net_init_tap,
953         [NET_CLIENT_DRIVER_SOCKET]    = net_init_socket,
954 #ifdef CONFIG_VDE
955         [NET_CLIENT_DRIVER_VDE]       = net_init_vde,
956 #endif
957 #ifdef CONFIG_NETMAP
958         [NET_CLIENT_DRIVER_NETMAP]    = net_init_netmap,
959 #endif
960 #ifdef CONFIG_NET_BRIDGE
961         [NET_CLIENT_DRIVER_BRIDGE]    = net_init_bridge,
962 #endif
963         [NET_CLIENT_DRIVER_HUBPORT]   = net_init_hubport,
964 #ifdef CONFIG_VHOST_NET_USED
965         [NET_CLIENT_DRIVER_VHOST_USER] = net_init_vhost_user,
966 #endif
967 #ifdef CONFIG_L2TPV3
968         [NET_CLIENT_DRIVER_L2TPV3]    = net_init_l2tpv3,
969 #endif
970 };
971 
972 
973 static int net_client_init1(const void *object, bool is_netdev, Error **errp)
974 {
975     Netdev legacy = {0};
976     const Netdev *netdev;
977     const char *name;
978     NetClientState *peer = NULL;
979 
980     if (is_netdev) {
981         netdev = object;
982         name = netdev->id;
983 
984         if (netdev->type == NET_CLIENT_DRIVER_NIC ||
985             !net_client_init_fun[netdev->type]) {
986             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
987                        "a netdev backend type");
988             return -1;
989         }
990     } else {
991         const NetLegacy *net = object;
992         const NetLegacyOptions *opts = net->opts;
993         legacy.id = net->id;
994         netdev = &legacy;
995         /* missing optional values have been initialized to "all bits zero" */
996         name = net->has_id ? net->id : net->name;
997 
998         if (net->has_name) {
999             warn_report("The 'name' parameter is deprecated, use 'id' instead");
1000         }
1001 
1002         /* Map the old options to the new flat type */
1003         switch (opts->type) {
1004         case NET_LEGACY_OPTIONS_TYPE_NONE:
1005             return 0; /* nothing to do */
1006         case NET_LEGACY_OPTIONS_TYPE_NIC:
1007             legacy.type = NET_CLIENT_DRIVER_NIC;
1008             legacy.u.nic = opts->u.nic;
1009             break;
1010         case NET_LEGACY_OPTIONS_TYPE_USER:
1011             legacy.type = NET_CLIENT_DRIVER_USER;
1012             legacy.u.user = opts->u.user;
1013             break;
1014         case NET_LEGACY_OPTIONS_TYPE_TAP:
1015             legacy.type = NET_CLIENT_DRIVER_TAP;
1016             legacy.u.tap = opts->u.tap;
1017             break;
1018         case NET_LEGACY_OPTIONS_TYPE_L2TPV3:
1019             legacy.type = NET_CLIENT_DRIVER_L2TPV3;
1020             legacy.u.l2tpv3 = opts->u.l2tpv3;
1021             break;
1022         case NET_LEGACY_OPTIONS_TYPE_SOCKET:
1023             legacy.type = NET_CLIENT_DRIVER_SOCKET;
1024             legacy.u.socket = opts->u.socket;
1025             break;
1026         case NET_LEGACY_OPTIONS_TYPE_VDE:
1027             legacy.type = NET_CLIENT_DRIVER_VDE;
1028             legacy.u.vde = opts->u.vde;
1029             break;
1030         case NET_LEGACY_OPTIONS_TYPE_BRIDGE:
1031             legacy.type = NET_CLIENT_DRIVER_BRIDGE;
1032             legacy.u.bridge = opts->u.bridge;
1033             break;
1034         case NET_LEGACY_OPTIONS_TYPE_NETMAP:
1035             legacy.type = NET_CLIENT_DRIVER_NETMAP;
1036             legacy.u.netmap = opts->u.netmap;
1037             break;
1038         case NET_LEGACY_OPTIONS_TYPE_VHOST_USER:
1039             legacy.type = NET_CLIENT_DRIVER_VHOST_USER;
1040             legacy.u.vhost_user = opts->u.vhost_user;
1041             break;
1042         default:
1043             abort();
1044         }
1045 
1046         if (!net_client_init_fun[netdev->type]) {
1047             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
1048                        "a net backend type (maybe it is not compiled "
1049                        "into this binary)");
1050             return -1;
1051         }
1052 
1053         /* Do not add to a hub if it's a nic with a netdev= parameter. */
1054         if (netdev->type != NET_CLIENT_DRIVER_NIC ||
1055             !opts->u.nic.has_netdev) {
1056             peer = net_hub_add_port(0, NULL, NULL);
1057         }
1058     }
1059 
1060     if (net_client_init_fun[netdev->type](netdev, name, peer, errp) < 0) {
1061         /* FIXME drop when all init functions store an Error */
1062         if (errp && !*errp) {
1063             error_setg(errp, QERR_DEVICE_INIT_FAILED,
1064                        NetClientDriver_str(netdev->type));
1065         }
1066         return -1;
1067     }
1068     return 0;
1069 }
1070 
1071 static void show_netdevs(void)
1072 {
1073     int idx;
1074     const char *available_netdevs[] = {
1075         "socket",
1076         "hubport",
1077         "tap",
1078 #ifdef CONFIG_SLIRP
1079         "user",
1080 #endif
1081 #ifdef CONFIG_L2TPV3
1082         "l2tpv3",
1083 #endif
1084 #ifdef CONFIG_VDE
1085         "vde",
1086 #endif
1087 #ifdef CONFIG_NET_BRIDGE
1088         "bridge",
1089 #endif
1090 #ifdef CONFIG_NETMAP
1091         "netmap",
1092 #endif
1093 #ifdef CONFIG_POSIX
1094         "vhost-user",
1095 #endif
1096     };
1097 
1098     printf("Available netdev backend types:\n");
1099     for (idx = 0; idx < ARRAY_SIZE(available_netdevs); idx++) {
1100         puts(available_netdevs[idx]);
1101     }
1102 }
1103 
1104 static int net_client_init(QemuOpts *opts, bool is_netdev, Error **errp)
1105 {
1106     void *object = NULL;
1107     Error *err = NULL;
1108     int ret = -1;
1109     Visitor *v = opts_visitor_new(opts);
1110 
1111     const char *type = qemu_opt_get(opts, "type");
1112 
1113     if (is_netdev && type && is_help_option(type)) {
1114         show_netdevs();
1115         exit(0);
1116     } else {
1117         /* Parse convenience option format ip6-net=fec0::0[/64] */
1118         const char *ip6_net = qemu_opt_get(opts, "ipv6-net");
1119 
1120         if (ip6_net) {
1121             char buf[strlen(ip6_net) + 1];
1122 
1123             if (get_str_sep(buf, sizeof(buf), &ip6_net, '/') < 0) {
1124                 /* Default 64bit prefix length.  */
1125                 qemu_opt_set(opts, "ipv6-prefix", ip6_net, &error_abort);
1126                 qemu_opt_set_number(opts, "ipv6-prefixlen", 64, &error_abort);
1127             } else {
1128                 /* User-specified prefix length.  */
1129                 unsigned long len;
1130                 int err;
1131 
1132                 qemu_opt_set(opts, "ipv6-prefix", buf, &error_abort);
1133                 err = qemu_strtoul(ip6_net, NULL, 10, &len);
1134 
1135                 if (err) {
1136                     error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1137                               "ipv6-prefix", "a number");
1138                 } else {
1139                     qemu_opt_set_number(opts, "ipv6-prefixlen", len,
1140                                         &error_abort);
1141                 }
1142             }
1143             qemu_opt_unset(opts, "ipv6-net");
1144         }
1145     }
1146 
1147     if (is_netdev) {
1148         visit_type_Netdev(v, NULL, (Netdev **)&object, &err);
1149     } else {
1150         visit_type_NetLegacy(v, NULL, (NetLegacy **)&object, &err);
1151     }
1152 
1153     if (!err) {
1154         ret = net_client_init1(object, is_netdev, &err);
1155     }
1156 
1157     if (is_netdev) {
1158         qapi_free_Netdev(object);
1159     } else {
1160         qapi_free_NetLegacy(object);
1161     }
1162 
1163     error_propagate(errp, err);
1164     visit_free(v);
1165     return ret;
1166 }
1167 
1168 void netdev_add(QemuOpts *opts, Error **errp)
1169 {
1170     net_client_init(opts, true, errp);
1171 }
1172 
1173 void qmp_netdev_add(QDict *qdict, QObject **ret, Error **errp)
1174 {
1175     Error *local_err = NULL;
1176     QemuOptsList *opts_list;
1177     QemuOpts *opts;
1178 
1179     opts_list = qemu_find_opts_err("netdev", &local_err);
1180     if (local_err) {
1181         goto out;
1182     }
1183 
1184     opts = qemu_opts_from_qdict(opts_list, qdict, &local_err);
1185     if (local_err) {
1186         goto out;
1187     }
1188 
1189     netdev_add(opts, &local_err);
1190     if (local_err) {
1191         qemu_opts_del(opts);
1192         goto out;
1193     }
1194 
1195 out:
1196     error_propagate(errp, local_err);
1197 }
1198 
1199 void qmp_netdev_del(const char *id, Error **errp)
1200 {
1201     NetClientState *nc;
1202     QemuOpts *opts;
1203 
1204     nc = qemu_find_netdev(id);
1205     if (!nc) {
1206         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1207                   "Device '%s' not found", id);
1208         return;
1209     }
1210 
1211     opts = qemu_opts_find(qemu_find_opts_err("netdev", NULL), id);
1212     if (!opts) {
1213         error_setg(errp, "Device '%s' is not a netdev", id);
1214         return;
1215     }
1216 
1217     qemu_del_net_client(nc);
1218     qemu_opts_del(opts);
1219 }
1220 
1221 static void netfilter_print_info(Monitor *mon, NetFilterState *nf)
1222 {
1223     char *str;
1224     ObjectProperty *prop;
1225     ObjectPropertyIterator iter;
1226     Visitor *v;
1227 
1228     /* generate info str */
1229     object_property_iter_init(&iter, OBJECT(nf));
1230     while ((prop = object_property_iter_next(&iter))) {
1231         if (!strcmp(prop->name, "type")) {
1232             continue;
1233         }
1234         v = string_output_visitor_new(false, &str);
1235         object_property_get(OBJECT(nf), v, prop->name, NULL);
1236         visit_complete(v, &str);
1237         visit_free(v);
1238         monitor_printf(mon, ",%s=%s", prop->name, str);
1239         g_free(str);
1240     }
1241     monitor_printf(mon, "\n");
1242 }
1243 
1244 void print_net_client(Monitor *mon, NetClientState *nc)
1245 {
1246     NetFilterState *nf;
1247 
1248     monitor_printf(mon, "%s: index=%d,type=%s,%s\n", nc->name,
1249                    nc->queue_index,
1250                    NetClientDriver_str(nc->info->type),
1251                    nc->info_str);
1252     if (!QTAILQ_EMPTY(&nc->filters)) {
1253         monitor_printf(mon, "filters:\n");
1254     }
1255     QTAILQ_FOREACH(nf, &nc->filters, next) {
1256         char *path = object_get_canonical_path_component(OBJECT(nf));
1257 
1258         monitor_printf(mon, "  - %s: type=%s", path,
1259                        object_get_typename(OBJECT(nf)));
1260         netfilter_print_info(mon, nf);
1261         g_free(path);
1262     }
1263 }
1264 
1265 RxFilterInfoList *qmp_query_rx_filter(bool has_name, const char *name,
1266                                       Error **errp)
1267 {
1268     NetClientState *nc;
1269     RxFilterInfoList *filter_list = NULL, *last_entry = NULL;
1270 
1271     QTAILQ_FOREACH(nc, &net_clients, next) {
1272         RxFilterInfoList *entry;
1273         RxFilterInfo *info;
1274 
1275         if (has_name && strcmp(nc->name, name) != 0) {
1276             continue;
1277         }
1278 
1279         /* only query rx-filter information of NIC */
1280         if (nc->info->type != NET_CLIENT_DRIVER_NIC) {
1281             if (has_name) {
1282                 error_setg(errp, "net client(%s) isn't a NIC", name);
1283                 return NULL;
1284             }
1285             continue;
1286         }
1287 
1288         /* only query information on queue 0 since the info is per nic,
1289          * not per queue
1290          */
1291         if (nc->queue_index != 0)
1292             continue;
1293 
1294         if (nc->info->query_rx_filter) {
1295             info = nc->info->query_rx_filter(nc);
1296             entry = g_malloc0(sizeof(*entry));
1297             entry->value = info;
1298 
1299             if (!filter_list) {
1300                 filter_list = entry;
1301             } else {
1302                 last_entry->next = entry;
1303             }
1304             last_entry = entry;
1305         } else if (has_name) {
1306             error_setg(errp, "net client(%s) doesn't support"
1307                        " rx-filter querying", name);
1308             return NULL;
1309         }
1310 
1311         if (has_name) {
1312             break;
1313         }
1314     }
1315 
1316     if (filter_list == NULL && has_name) {
1317         error_setg(errp, "invalid net client name: %s", name);
1318     }
1319 
1320     return filter_list;
1321 }
1322 
1323 void hmp_info_network(Monitor *mon, const QDict *qdict)
1324 {
1325     NetClientState *nc, *peer;
1326     NetClientDriver type;
1327 
1328     net_hub_info(mon);
1329 
1330     QTAILQ_FOREACH(nc, &net_clients, next) {
1331         peer = nc->peer;
1332         type = nc->info->type;
1333 
1334         /* Skip if already printed in hub info */
1335         if (net_hub_id_for_client(nc, NULL) == 0) {
1336             continue;
1337         }
1338 
1339         if (!peer || type == NET_CLIENT_DRIVER_NIC) {
1340             print_net_client(mon, nc);
1341         } /* else it's a netdev connected to a NIC, printed with the NIC */
1342         if (peer && type == NET_CLIENT_DRIVER_NIC) {
1343             monitor_printf(mon, " \\ ");
1344             print_net_client(mon, peer);
1345         }
1346     }
1347 }
1348 
1349 void colo_notify_filters_event(int event, Error **errp)
1350 {
1351     NetClientState *nc;
1352     NetFilterState *nf;
1353     NetFilterClass *nfc = NULL;
1354     Error *local_err = NULL;
1355 
1356     QTAILQ_FOREACH(nc, &net_clients, next) {
1357         QTAILQ_FOREACH(nf, &nc->filters, next) {
1358             nfc = NETFILTER_GET_CLASS(OBJECT(nf));
1359             nfc->handle_event(nf, event, &local_err);
1360             if (local_err) {
1361                 error_propagate(errp, local_err);
1362                 return;
1363             }
1364         }
1365     }
1366 }
1367 
1368 void qmp_set_link(const char *name, bool up, Error **errp)
1369 {
1370     NetClientState *ncs[MAX_QUEUE_NUM];
1371     NetClientState *nc;
1372     int queues, i;
1373 
1374     queues = qemu_find_net_clients_except(name, ncs,
1375                                           NET_CLIENT_DRIVER__MAX,
1376                                           MAX_QUEUE_NUM);
1377 
1378     if (queues == 0) {
1379         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1380                   "Device '%s' not found", name);
1381         return;
1382     }
1383     nc = ncs[0];
1384 
1385     for (i = 0; i < queues; i++) {
1386         ncs[i]->link_down = !up;
1387     }
1388 
1389     if (nc->info->link_status_changed) {
1390         nc->info->link_status_changed(nc);
1391     }
1392 
1393     if (nc->peer) {
1394         /* Change peer link only if the peer is NIC and then notify peer.
1395          * If the peer is a HUBPORT or a backend, we do not change the
1396          * link status.
1397          *
1398          * This behavior is compatible with qemu hubs where there could be
1399          * multiple clients that can still communicate with each other in
1400          * disconnected mode. For now maintain this compatibility.
1401          */
1402         if (nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
1403             for (i = 0; i < queues; i++) {
1404                 ncs[i]->peer->link_down = !up;
1405             }
1406         }
1407         if (nc->peer->info->link_status_changed) {
1408             nc->peer->info->link_status_changed(nc->peer);
1409         }
1410     }
1411 }
1412 
1413 static void net_vm_change_state_handler(void *opaque, int running,
1414                                         RunState state)
1415 {
1416     NetClientState *nc;
1417     NetClientState *tmp;
1418 
1419     QTAILQ_FOREACH_SAFE(nc, &net_clients, next, tmp) {
1420         if (running) {
1421             /* Flush queued packets and wake up backends. */
1422             if (nc->peer && qemu_can_send_packet(nc)) {
1423                 qemu_flush_queued_packets(nc->peer);
1424             }
1425         } else {
1426             /* Complete all queued packets, to guarantee we don't modify
1427              * state later when VM is not running.
1428              */
1429             qemu_flush_or_purge_queued_packets(nc, true);
1430         }
1431     }
1432 }
1433 
1434 void net_cleanup(void)
1435 {
1436     NetClientState *nc;
1437 
1438     /* We may del multiple entries during qemu_del_net_client(),
1439      * so QTAILQ_FOREACH_SAFE() is also not safe here.
1440      */
1441     while (!QTAILQ_EMPTY(&net_clients)) {
1442         nc = QTAILQ_FIRST(&net_clients);
1443         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
1444             qemu_del_nic(qemu_get_nic(nc));
1445         } else {
1446             qemu_del_net_client(nc);
1447         }
1448     }
1449 
1450     qemu_del_vm_change_state_handler(net_change_state_entry);
1451 }
1452 
1453 void net_check_clients(void)
1454 {
1455     NetClientState *nc;
1456     int i;
1457 
1458     net_hub_check_clients();
1459 
1460     QTAILQ_FOREACH(nc, &net_clients, next) {
1461         if (!nc->peer) {
1462             warn_report("%s %s has no peer",
1463                         nc->info->type == NET_CLIENT_DRIVER_NIC
1464                         ? "nic" : "netdev",
1465                         nc->name);
1466         }
1467     }
1468 
1469     /* Check that all NICs requested via -net nic actually got created.
1470      * NICs created via -device don't need to be checked here because
1471      * they are always instantiated.
1472      */
1473     for (i = 0; i < MAX_NICS; i++) {
1474         NICInfo *nd = &nd_table[i];
1475         if (nd->used && !nd->instantiated) {
1476             warn_report("requested NIC (%s, model %s) "
1477                         "was not created (not supported by this machine?)",
1478                         nd->name ? nd->name : "anonymous",
1479                         nd->model ? nd->model : "unspecified");
1480         }
1481     }
1482 }
1483 
1484 static int net_init_client(void *dummy, QemuOpts *opts, Error **errp)
1485 {
1486     return net_client_init(opts, false, errp);
1487 }
1488 
1489 static int net_init_netdev(void *dummy, QemuOpts *opts, Error **errp)
1490 {
1491     return net_client_init(opts, true, errp);
1492 }
1493 
1494 /* For the convenience "--nic" parameter */
1495 static int net_param_nic(void *dummy, QemuOpts *opts, Error **errp)
1496 {
1497     char *mac, *nd_id;
1498     int idx, ret;
1499     NICInfo *ni;
1500     const char *type;
1501 
1502     type = qemu_opt_get(opts, "type");
1503     if (type && g_str_equal(type, "none")) {
1504         return 0;    /* Nothing to do, default_net is cleared in vl.c */
1505     }
1506 
1507     idx = nic_get_free_idx();
1508     if (idx == -1 || nb_nics >= MAX_NICS) {
1509         error_setg(errp, "no more on-board/default NIC slots available");
1510         return -1;
1511     }
1512 
1513     if (!type) {
1514         qemu_opt_set(opts, "type", "user", &error_abort);
1515     }
1516 
1517     ni = &nd_table[idx];
1518     memset(ni, 0, sizeof(*ni));
1519     ni->model = qemu_opt_get_del(opts, "model");
1520 
1521     /* Create an ID if the user did not specify one */
1522     nd_id = g_strdup(qemu_opts_id(opts));
1523     if (!nd_id) {
1524         nd_id = g_strdup_printf("__org.qemu.nic%i\n", idx);
1525         qemu_opts_set_id(opts, nd_id);
1526     }
1527 
1528     /* Handle MAC address */
1529     mac = qemu_opt_get_del(opts, "mac");
1530     if (mac) {
1531         ret = net_parse_macaddr(ni->macaddr.a, mac);
1532         g_free(mac);
1533         if (ret) {
1534             error_setg(errp, "invalid syntax for ethernet address");
1535             goto out;
1536         }
1537         if (is_multicast_ether_addr(ni->macaddr.a)) {
1538             error_setg(errp, "NIC cannot have multicast MAC address");
1539             ret = -1;
1540             goto out;
1541         }
1542     }
1543     qemu_macaddr_default_if_unset(&ni->macaddr);
1544 
1545     ret = net_client_init(opts, true, errp);
1546     if (ret == 0) {
1547         ni->netdev = qemu_find_netdev(nd_id);
1548         ni->used = true;
1549         nb_nics++;
1550     }
1551 
1552 out:
1553     g_free(nd_id);
1554     return ret;
1555 }
1556 
1557 int net_init_clients(Error **errp)
1558 {
1559     net_change_state_entry =
1560         qemu_add_vm_change_state_handler(net_vm_change_state_handler, NULL);
1561 
1562     QTAILQ_INIT(&net_clients);
1563 
1564     if (qemu_opts_foreach(qemu_find_opts("netdev"),
1565                           net_init_netdev, NULL, errp)) {
1566         return -1;
1567     }
1568 
1569     if (qemu_opts_foreach(qemu_find_opts("nic"), net_param_nic, NULL, errp)) {
1570         return -1;
1571     }
1572 
1573     if (qemu_opts_foreach(qemu_find_opts("net"), net_init_client, NULL, errp)) {
1574         return -1;
1575     }
1576 
1577     return 0;
1578 }
1579 
1580 int net_client_parse(QemuOptsList *opts_list, const char *optarg)
1581 {
1582     if (!qemu_opts_parse_noisily(opts_list, optarg, true)) {
1583         return -1;
1584     }
1585 
1586     return 0;
1587 }
1588 
1589 /* From FreeBSD */
1590 /* XXX: optimize */
1591 uint32_t net_crc32(const uint8_t *p, int len)
1592 {
1593     uint32_t crc;
1594     int carry, i, j;
1595     uint8_t b;
1596 
1597     crc = 0xffffffff;
1598     for (i = 0; i < len; i++) {
1599         b = *p++;
1600         for (j = 0; j < 8; j++) {
1601             carry = ((crc & 0x80000000L) ? 1 : 0) ^ (b & 0x01);
1602             crc <<= 1;
1603             b >>= 1;
1604             if (carry) {
1605                 crc = ((crc ^ POLYNOMIAL_BE) | carry);
1606             }
1607         }
1608     }
1609 
1610     return crc;
1611 }
1612 
1613 uint32_t net_crc32_le(const uint8_t *p, int len)
1614 {
1615     uint32_t crc;
1616     int carry, i, j;
1617     uint8_t b;
1618 
1619     crc = 0xffffffff;
1620     for (i = 0; i < len; i++) {
1621         b = *p++;
1622         for (j = 0; j < 8; j++) {
1623             carry = (crc & 0x1) ^ (b & 0x01);
1624             crc >>= 1;
1625             b >>= 1;
1626             if (carry) {
1627                 crc ^= POLYNOMIAL_LE;
1628             }
1629         }
1630     }
1631 
1632     return crc;
1633 }
1634 
1635 QemuOptsList qemu_netdev_opts = {
1636     .name = "netdev",
1637     .implied_opt_name = "type",
1638     .head = QTAILQ_HEAD_INITIALIZER(qemu_netdev_opts.head),
1639     .desc = {
1640         /*
1641          * no elements => accept any params
1642          * validation will happen later
1643          */
1644         { /* end of list */ }
1645     },
1646 };
1647 
1648 QemuOptsList qemu_nic_opts = {
1649     .name = "nic",
1650     .implied_opt_name = "type",
1651     .head = QTAILQ_HEAD_INITIALIZER(qemu_nic_opts.head),
1652     .desc = {
1653         /*
1654          * no elements => accept any params
1655          * validation will happen later
1656          */
1657         { /* end of list */ }
1658     },
1659 };
1660 
1661 QemuOptsList qemu_net_opts = {
1662     .name = "net",
1663     .implied_opt_name = "type",
1664     .head = QTAILQ_HEAD_INITIALIZER(qemu_net_opts.head),
1665     .desc = {
1666         /*
1667          * no elements => accept any params
1668          * validation will happen later
1669          */
1670         { /* end of list */ }
1671     },
1672 };
1673 
1674 void net_socket_rs_init(SocketReadState *rs,
1675                         SocketReadStateFinalize *finalize,
1676                         bool vnet_hdr)
1677 {
1678     rs->state = 0;
1679     rs->vnet_hdr = vnet_hdr;
1680     rs->index = 0;
1681     rs->packet_len = 0;
1682     rs->vnet_hdr_len = 0;
1683     memset(rs->buf, 0, sizeof(rs->buf));
1684     rs->finalize = finalize;
1685 }
1686 
1687 /*
1688  * Returns
1689  * 0: success
1690  * -1: error occurs
1691  */
1692 int net_fill_rstate(SocketReadState *rs, const uint8_t *buf, int size)
1693 {
1694     unsigned int l;
1695 
1696     while (size > 0) {
1697         /* Reassemble a packet from the network.
1698          * 0 = getting length.
1699          * 1 = getting vnet header length.
1700          * 2 = getting data.
1701          */
1702         switch (rs->state) {
1703         case 0:
1704             l = 4 - rs->index;
1705             if (l > size) {
1706                 l = size;
1707             }
1708             memcpy(rs->buf + rs->index, buf, l);
1709             buf += l;
1710             size -= l;
1711             rs->index += l;
1712             if (rs->index == 4) {
1713                 /* got length */
1714                 rs->packet_len = ntohl(*(uint32_t *)rs->buf);
1715                 rs->index = 0;
1716                 if (rs->vnet_hdr) {
1717                     rs->state = 1;
1718                 } else {
1719                     rs->state = 2;
1720                     rs->vnet_hdr_len = 0;
1721                 }
1722             }
1723             break;
1724         case 1:
1725             l = 4 - rs->index;
1726             if (l > size) {
1727                 l = size;
1728             }
1729             memcpy(rs->buf + rs->index, buf, l);
1730             buf += l;
1731             size -= l;
1732             rs->index += l;
1733             if (rs->index == 4) {
1734                 /* got vnet header length */
1735                 rs->vnet_hdr_len = ntohl(*(uint32_t *)rs->buf);
1736                 rs->index = 0;
1737                 rs->state = 2;
1738             }
1739             break;
1740         case 2:
1741             l = rs->packet_len - rs->index;
1742             if (l > size) {
1743                 l = size;
1744             }
1745             if (rs->index + l <= sizeof(rs->buf)) {
1746                 memcpy(rs->buf + rs->index, buf, l);
1747             } else {
1748                 fprintf(stderr, "serious error: oversized packet received,"
1749                     "connection terminated.\n");
1750                 rs->index = rs->state = 0;
1751                 return -1;
1752             }
1753 
1754             rs->index += l;
1755             buf += l;
1756             size -= l;
1757             if (rs->index >= rs->packet_len) {
1758                 rs->index = 0;
1759                 rs->state = 0;
1760                 assert(rs->finalize);
1761                 rs->finalize(rs);
1762             }
1763             break;
1764         }
1765     }
1766 
1767     assert(size == 0);
1768     return 0;
1769 }
1770