xref: /openbmc/qemu/net/net.c (revision 6b8f9c6e)
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     printf("Supported NIC models:\n");
841     for (i = 0 ; models[i]; i++) {
842         printf("%s\n", models[i]);
843     }
844     return 1;
845 }
846 
847 void qemu_check_nic_model(NICInfo *nd, const char *model)
848 {
849     const char *models[2];
850 
851     models[0] = model;
852     models[1] = NULL;
853 
854     if (qemu_show_nic_models(nd->model, models))
855         exit(0);
856     if (qemu_find_nic_model(nd, models, model) < 0)
857         exit(1);
858 }
859 
860 int qemu_find_nic_model(NICInfo *nd, const char * const *models,
861                         const char *default_model)
862 {
863     int i;
864 
865     if (!nd->model)
866         nd->model = g_strdup(default_model);
867 
868     for (i = 0 ; models[i]; i++) {
869         if (strcmp(nd->model, models[i]) == 0)
870             return i;
871     }
872 
873     error_report("Unsupported NIC model: %s", nd->model);
874     return -1;
875 }
876 
877 static int net_init_nic(const Netdev *netdev, const char *name,
878                         NetClientState *peer, Error **errp)
879 {
880     int idx;
881     NICInfo *nd;
882     const NetLegacyNicOptions *nic;
883 
884     assert(netdev->type == NET_CLIENT_DRIVER_NIC);
885     nic = &netdev->u.nic;
886 
887     idx = nic_get_free_idx();
888     if (idx == -1 || nb_nics >= MAX_NICS) {
889         error_setg(errp, "too many NICs");
890         return -1;
891     }
892 
893     nd = &nd_table[idx];
894 
895     memset(nd, 0, sizeof(*nd));
896 
897     if (nic->has_netdev) {
898         nd->netdev = qemu_find_netdev(nic->netdev);
899         if (!nd->netdev) {
900             error_setg(errp, "netdev '%s' not found", nic->netdev);
901             return -1;
902         }
903     } else {
904         assert(peer);
905         nd->netdev = peer;
906     }
907     nd->name = g_strdup(name);
908     if (nic->has_model) {
909         nd->model = g_strdup(nic->model);
910     }
911     if (nic->has_addr) {
912         nd->devaddr = g_strdup(nic->addr);
913     }
914 
915     if (nic->has_macaddr &&
916         net_parse_macaddr(nd->macaddr.a, nic->macaddr) < 0) {
917         error_setg(errp, "invalid syntax for ethernet address");
918         return -1;
919     }
920     if (nic->has_macaddr &&
921         is_multicast_ether_addr(nd->macaddr.a)) {
922         error_setg(errp,
923                    "NIC cannot have multicast MAC address (odd 1st byte)");
924         return -1;
925     }
926     qemu_macaddr_default_if_unset(&nd->macaddr);
927 
928     if (nic->has_vectors) {
929         if (nic->vectors > 0x7ffffff) {
930             error_setg(errp, "invalid # of vectors: %"PRIu32, nic->vectors);
931             return -1;
932         }
933         nd->nvectors = nic->vectors;
934     } else {
935         nd->nvectors = DEV_NVECTORS_UNSPECIFIED;
936     }
937 
938     nd->used = 1;
939     nb_nics++;
940 
941     return idx;
942 }
943 
944 
945 static int (* const net_client_init_fun[NET_CLIENT_DRIVER__MAX])(
946     const Netdev *netdev,
947     const char *name,
948     NetClientState *peer, Error **errp) = {
949         [NET_CLIENT_DRIVER_NIC]       = net_init_nic,
950 #ifdef CONFIG_SLIRP
951         [NET_CLIENT_DRIVER_USER]      = net_init_slirp,
952 #endif
953         [NET_CLIENT_DRIVER_TAP]       = net_init_tap,
954         [NET_CLIENT_DRIVER_SOCKET]    = net_init_socket,
955 #ifdef CONFIG_VDE
956         [NET_CLIENT_DRIVER_VDE]       = net_init_vde,
957 #endif
958 #ifdef CONFIG_NETMAP
959         [NET_CLIENT_DRIVER_NETMAP]    = net_init_netmap,
960 #endif
961 #ifdef CONFIG_NET_BRIDGE
962         [NET_CLIENT_DRIVER_BRIDGE]    = net_init_bridge,
963 #endif
964         [NET_CLIENT_DRIVER_HUBPORT]   = net_init_hubport,
965 #ifdef CONFIG_VHOST_NET_USER
966         [NET_CLIENT_DRIVER_VHOST_USER] = net_init_vhost_user,
967 #endif
968 #ifdef CONFIG_L2TPV3
969         [NET_CLIENT_DRIVER_L2TPV3]    = net_init_l2tpv3,
970 #endif
971 };
972 
973 
974 static int net_client_init1(const void *object, bool is_netdev, Error **errp)
975 {
976     Netdev legacy = {0};
977     const Netdev *netdev;
978     const char *name;
979     NetClientState *peer = NULL;
980 
981     if (is_netdev) {
982         netdev = object;
983         name = netdev->id;
984 
985         if (netdev->type == NET_CLIENT_DRIVER_NIC ||
986             !net_client_init_fun[netdev->type]) {
987             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
988                        "a netdev backend type");
989             return -1;
990         }
991     } else {
992         const NetLegacy *net = object;
993         const NetLegacyOptions *opts = net->opts;
994         legacy.id = net->id;
995         netdev = &legacy;
996         /* missing optional values have been initialized to "all bits zero" */
997         name = net->has_id ? net->id : net->name;
998 
999         if (net->has_name) {
1000             warn_report("The 'name' parameter is deprecated, use 'id' instead");
1001         }
1002 
1003         /* Map the old options to the new flat type */
1004         switch (opts->type) {
1005         case NET_LEGACY_OPTIONS_TYPE_NONE:
1006             return 0; /* nothing to do */
1007         case NET_LEGACY_OPTIONS_TYPE_NIC:
1008             legacy.type = NET_CLIENT_DRIVER_NIC;
1009             legacy.u.nic = opts->u.nic;
1010             break;
1011         case NET_LEGACY_OPTIONS_TYPE_USER:
1012             legacy.type = NET_CLIENT_DRIVER_USER;
1013             legacy.u.user = opts->u.user;
1014             break;
1015         case NET_LEGACY_OPTIONS_TYPE_TAP:
1016             legacy.type = NET_CLIENT_DRIVER_TAP;
1017             legacy.u.tap = opts->u.tap;
1018             break;
1019         case NET_LEGACY_OPTIONS_TYPE_L2TPV3:
1020             legacy.type = NET_CLIENT_DRIVER_L2TPV3;
1021             legacy.u.l2tpv3 = opts->u.l2tpv3;
1022             break;
1023         case NET_LEGACY_OPTIONS_TYPE_SOCKET:
1024             legacy.type = NET_CLIENT_DRIVER_SOCKET;
1025             legacy.u.socket = opts->u.socket;
1026             break;
1027         case NET_LEGACY_OPTIONS_TYPE_VDE:
1028             legacy.type = NET_CLIENT_DRIVER_VDE;
1029             legacy.u.vde = opts->u.vde;
1030             break;
1031         case NET_LEGACY_OPTIONS_TYPE_BRIDGE:
1032             legacy.type = NET_CLIENT_DRIVER_BRIDGE;
1033             legacy.u.bridge = opts->u.bridge;
1034             break;
1035         case NET_LEGACY_OPTIONS_TYPE_NETMAP:
1036             legacy.type = NET_CLIENT_DRIVER_NETMAP;
1037             legacy.u.netmap = opts->u.netmap;
1038             break;
1039         case NET_LEGACY_OPTIONS_TYPE_VHOST_USER:
1040             legacy.type = NET_CLIENT_DRIVER_VHOST_USER;
1041             legacy.u.vhost_user = opts->u.vhost_user;
1042             break;
1043         default:
1044             abort();
1045         }
1046 
1047         if (!net_client_init_fun[netdev->type]) {
1048             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
1049                        "a net backend type (maybe it is not compiled "
1050                        "into this binary)");
1051             return -1;
1052         }
1053 
1054         /* Do not add to a hub if it's a nic with a netdev= parameter. */
1055         if (netdev->type != NET_CLIENT_DRIVER_NIC ||
1056             !opts->u.nic.has_netdev) {
1057             peer = net_hub_add_port(0, NULL, NULL);
1058         }
1059     }
1060 
1061     if (net_client_init_fun[netdev->type](netdev, name, peer, errp) < 0) {
1062         /* FIXME drop when all init functions store an Error */
1063         if (errp && !*errp) {
1064             error_setg(errp, QERR_DEVICE_INIT_FAILED,
1065                        NetClientDriver_str(netdev->type));
1066         }
1067         return -1;
1068     }
1069     return 0;
1070 }
1071 
1072 static void show_netdevs(void)
1073 {
1074     int idx;
1075     const char *available_netdevs[] = {
1076         "socket",
1077         "hubport",
1078         "tap",
1079 #ifdef CONFIG_SLIRP
1080         "user",
1081 #endif
1082 #ifdef CONFIG_L2TPV3
1083         "l2tpv3",
1084 #endif
1085 #ifdef CONFIG_VDE
1086         "vde",
1087 #endif
1088 #ifdef CONFIG_NET_BRIDGE
1089         "bridge",
1090 #endif
1091 #ifdef CONFIG_NETMAP
1092         "netmap",
1093 #endif
1094 #ifdef CONFIG_POSIX
1095         "vhost-user",
1096 #endif
1097     };
1098 
1099     printf("Available netdev backend types:\n");
1100     for (idx = 0; idx < ARRAY_SIZE(available_netdevs); idx++) {
1101         puts(available_netdevs[idx]);
1102     }
1103 }
1104 
1105 static int net_client_init(QemuOpts *opts, bool is_netdev, Error **errp)
1106 {
1107     void *object = NULL;
1108     Error *err = NULL;
1109     int ret = -1;
1110     Visitor *v = opts_visitor_new(opts);
1111 
1112     const char *type = qemu_opt_get(opts, "type");
1113 
1114     if (is_netdev && type && is_help_option(type)) {
1115         show_netdevs();
1116         exit(0);
1117     } else {
1118         /* Parse convenience option format ip6-net=fec0::0[/64] */
1119         const char *ip6_net = qemu_opt_get(opts, "ipv6-net");
1120 
1121         if (ip6_net) {
1122             char buf[strlen(ip6_net) + 1];
1123 
1124             if (get_str_sep(buf, sizeof(buf), &ip6_net, '/') < 0) {
1125                 /* Default 64bit prefix length.  */
1126                 qemu_opt_set(opts, "ipv6-prefix", ip6_net, &error_abort);
1127                 qemu_opt_set_number(opts, "ipv6-prefixlen", 64, &error_abort);
1128             } else {
1129                 /* User-specified prefix length.  */
1130                 unsigned long len;
1131                 int err;
1132 
1133                 qemu_opt_set(opts, "ipv6-prefix", buf, &error_abort);
1134                 err = qemu_strtoul(ip6_net, NULL, 10, &len);
1135 
1136                 if (err) {
1137                     error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1138                               "ipv6-prefix", "a number");
1139                 } else {
1140                     qemu_opt_set_number(opts, "ipv6-prefixlen", len,
1141                                         &error_abort);
1142                 }
1143             }
1144             qemu_opt_unset(opts, "ipv6-net");
1145         }
1146     }
1147 
1148     if (is_netdev) {
1149         visit_type_Netdev(v, NULL, (Netdev **)&object, &err);
1150     } else {
1151         visit_type_NetLegacy(v, NULL, (NetLegacy **)&object, &err);
1152     }
1153 
1154     if (!err) {
1155         ret = net_client_init1(object, is_netdev, &err);
1156     }
1157 
1158     if (is_netdev) {
1159         qapi_free_Netdev(object);
1160     } else {
1161         qapi_free_NetLegacy(object);
1162     }
1163 
1164     error_propagate(errp, err);
1165     visit_free(v);
1166     return ret;
1167 }
1168 
1169 void netdev_add(QemuOpts *opts, Error **errp)
1170 {
1171     net_client_init(opts, true, errp);
1172 }
1173 
1174 void qmp_netdev_add(QDict *qdict, QObject **ret, Error **errp)
1175 {
1176     Error *local_err = NULL;
1177     QemuOptsList *opts_list;
1178     QemuOpts *opts;
1179 
1180     opts_list = qemu_find_opts_err("netdev", &local_err);
1181     if (local_err) {
1182         goto out;
1183     }
1184 
1185     opts = qemu_opts_from_qdict(opts_list, qdict, &local_err);
1186     if (local_err) {
1187         goto out;
1188     }
1189 
1190     netdev_add(opts, &local_err);
1191     if (local_err) {
1192         qemu_opts_del(opts);
1193         goto out;
1194     }
1195 
1196 out:
1197     error_propagate(errp, local_err);
1198 }
1199 
1200 void qmp_netdev_del(const char *id, Error **errp)
1201 {
1202     NetClientState *nc;
1203     QemuOpts *opts;
1204 
1205     nc = qemu_find_netdev(id);
1206     if (!nc) {
1207         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1208                   "Device '%s' not found", id);
1209         return;
1210     }
1211 
1212     opts = qemu_opts_find(qemu_find_opts_err("netdev", NULL), id);
1213     if (!opts) {
1214         error_setg(errp, "Device '%s' is not a netdev", id);
1215         return;
1216     }
1217 
1218     qemu_del_net_client(nc);
1219     qemu_opts_del(opts);
1220 }
1221 
1222 static void netfilter_print_info(Monitor *mon, NetFilterState *nf)
1223 {
1224     char *str;
1225     ObjectProperty *prop;
1226     ObjectPropertyIterator iter;
1227     Visitor *v;
1228 
1229     /* generate info str */
1230     object_property_iter_init(&iter, OBJECT(nf));
1231     while ((prop = object_property_iter_next(&iter))) {
1232         if (!strcmp(prop->name, "type")) {
1233             continue;
1234         }
1235         v = string_output_visitor_new(false, &str);
1236         object_property_get(OBJECT(nf), v, prop->name, NULL);
1237         visit_complete(v, &str);
1238         visit_free(v);
1239         monitor_printf(mon, ",%s=%s", prop->name, str);
1240         g_free(str);
1241     }
1242     monitor_printf(mon, "\n");
1243 }
1244 
1245 void print_net_client(Monitor *mon, NetClientState *nc)
1246 {
1247     NetFilterState *nf;
1248 
1249     monitor_printf(mon, "%s: index=%d,type=%s,%s\n", nc->name,
1250                    nc->queue_index,
1251                    NetClientDriver_str(nc->info->type),
1252                    nc->info_str);
1253     if (!QTAILQ_EMPTY(&nc->filters)) {
1254         monitor_printf(mon, "filters:\n");
1255     }
1256     QTAILQ_FOREACH(nf, &nc->filters, next) {
1257         char *path = object_get_canonical_path_component(OBJECT(nf));
1258 
1259         monitor_printf(mon, "  - %s: type=%s", path,
1260                        object_get_typename(OBJECT(nf)));
1261         netfilter_print_info(mon, nf);
1262         g_free(path);
1263     }
1264 }
1265 
1266 RxFilterInfoList *qmp_query_rx_filter(bool has_name, const char *name,
1267                                       Error **errp)
1268 {
1269     NetClientState *nc;
1270     RxFilterInfoList *filter_list = NULL, *last_entry = NULL;
1271 
1272     QTAILQ_FOREACH(nc, &net_clients, next) {
1273         RxFilterInfoList *entry;
1274         RxFilterInfo *info;
1275 
1276         if (has_name && strcmp(nc->name, name) != 0) {
1277             continue;
1278         }
1279 
1280         /* only query rx-filter information of NIC */
1281         if (nc->info->type != NET_CLIENT_DRIVER_NIC) {
1282             if (has_name) {
1283                 error_setg(errp, "net client(%s) isn't a NIC", name);
1284                 return NULL;
1285             }
1286             continue;
1287         }
1288 
1289         /* only query information on queue 0 since the info is per nic,
1290          * not per queue
1291          */
1292         if (nc->queue_index != 0)
1293             continue;
1294 
1295         if (nc->info->query_rx_filter) {
1296             info = nc->info->query_rx_filter(nc);
1297             entry = g_malloc0(sizeof(*entry));
1298             entry->value = info;
1299 
1300             if (!filter_list) {
1301                 filter_list = entry;
1302             } else {
1303                 last_entry->next = entry;
1304             }
1305             last_entry = entry;
1306         } else if (has_name) {
1307             error_setg(errp, "net client(%s) doesn't support"
1308                        " rx-filter querying", name);
1309             return NULL;
1310         }
1311 
1312         if (has_name) {
1313             break;
1314         }
1315     }
1316 
1317     if (filter_list == NULL && has_name) {
1318         error_setg(errp, "invalid net client name: %s", name);
1319     }
1320 
1321     return filter_list;
1322 }
1323 
1324 void hmp_info_network(Monitor *mon, const QDict *qdict)
1325 {
1326     NetClientState *nc, *peer;
1327     NetClientDriver type;
1328 
1329     net_hub_info(mon);
1330 
1331     QTAILQ_FOREACH(nc, &net_clients, next) {
1332         peer = nc->peer;
1333         type = nc->info->type;
1334 
1335         /* Skip if already printed in hub info */
1336         if (net_hub_id_for_client(nc, NULL) == 0) {
1337             continue;
1338         }
1339 
1340         if (!peer || type == NET_CLIENT_DRIVER_NIC) {
1341             print_net_client(mon, nc);
1342         } /* else it's a netdev connected to a NIC, printed with the NIC */
1343         if (peer && type == NET_CLIENT_DRIVER_NIC) {
1344             monitor_printf(mon, " \\ ");
1345             print_net_client(mon, peer);
1346         }
1347     }
1348 }
1349 
1350 void colo_notify_filters_event(int event, Error **errp)
1351 {
1352     NetClientState *nc;
1353     NetFilterState *nf;
1354     NetFilterClass *nfc = NULL;
1355     Error *local_err = NULL;
1356 
1357     QTAILQ_FOREACH(nc, &net_clients, next) {
1358         QTAILQ_FOREACH(nf, &nc->filters, next) {
1359             nfc = NETFILTER_GET_CLASS(OBJECT(nf));
1360             nfc->handle_event(nf, event, &local_err);
1361             if (local_err) {
1362                 error_propagate(errp, local_err);
1363                 return;
1364             }
1365         }
1366     }
1367 }
1368 
1369 void qmp_set_link(const char *name, bool up, Error **errp)
1370 {
1371     NetClientState *ncs[MAX_QUEUE_NUM];
1372     NetClientState *nc;
1373     int queues, i;
1374 
1375     queues = qemu_find_net_clients_except(name, ncs,
1376                                           NET_CLIENT_DRIVER__MAX,
1377                                           MAX_QUEUE_NUM);
1378 
1379     if (queues == 0) {
1380         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1381                   "Device '%s' not found", name);
1382         return;
1383     }
1384     nc = ncs[0];
1385 
1386     for (i = 0; i < queues; i++) {
1387         ncs[i]->link_down = !up;
1388     }
1389 
1390     if (nc->info->link_status_changed) {
1391         nc->info->link_status_changed(nc);
1392     }
1393 
1394     if (nc->peer) {
1395         /* Change peer link only if the peer is NIC and then notify peer.
1396          * If the peer is a HUBPORT or a backend, we do not change the
1397          * link status.
1398          *
1399          * This behavior is compatible with qemu hubs where there could be
1400          * multiple clients that can still communicate with each other in
1401          * disconnected mode. For now maintain this compatibility.
1402          */
1403         if (nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
1404             for (i = 0; i < queues; i++) {
1405                 ncs[i]->peer->link_down = !up;
1406             }
1407         }
1408         if (nc->peer->info->link_status_changed) {
1409             nc->peer->info->link_status_changed(nc->peer);
1410         }
1411     }
1412 }
1413 
1414 static void net_vm_change_state_handler(void *opaque, int running,
1415                                         RunState state)
1416 {
1417     NetClientState *nc;
1418     NetClientState *tmp;
1419 
1420     QTAILQ_FOREACH_SAFE(nc, &net_clients, next, tmp) {
1421         if (running) {
1422             /* Flush queued packets and wake up backends. */
1423             if (nc->peer && qemu_can_send_packet(nc)) {
1424                 qemu_flush_queued_packets(nc->peer);
1425             }
1426         } else {
1427             /* Complete all queued packets, to guarantee we don't modify
1428              * state later when VM is not running.
1429              */
1430             qemu_flush_or_purge_queued_packets(nc, true);
1431         }
1432     }
1433 }
1434 
1435 void net_cleanup(void)
1436 {
1437     NetClientState *nc;
1438 
1439     /* We may del multiple entries during qemu_del_net_client(),
1440      * so QTAILQ_FOREACH_SAFE() is also not safe here.
1441      */
1442     while (!QTAILQ_EMPTY(&net_clients)) {
1443         nc = QTAILQ_FIRST(&net_clients);
1444         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
1445             qemu_del_nic(qemu_get_nic(nc));
1446         } else {
1447             qemu_del_net_client(nc);
1448         }
1449     }
1450 
1451     qemu_del_vm_change_state_handler(net_change_state_entry);
1452 }
1453 
1454 void net_check_clients(void)
1455 {
1456     NetClientState *nc;
1457     int i;
1458 
1459     net_hub_check_clients();
1460 
1461     QTAILQ_FOREACH(nc, &net_clients, next) {
1462         if (!nc->peer) {
1463             warn_report("%s %s has no peer",
1464                         nc->info->type == NET_CLIENT_DRIVER_NIC
1465                         ? "nic" : "netdev",
1466                         nc->name);
1467         }
1468     }
1469 
1470     /* Check that all NICs requested via -net nic actually got created.
1471      * NICs created via -device don't need to be checked here because
1472      * they are always instantiated.
1473      */
1474     for (i = 0; i < MAX_NICS; i++) {
1475         NICInfo *nd = &nd_table[i];
1476         if (nd->used && !nd->instantiated) {
1477             warn_report("requested NIC (%s, model %s) "
1478                         "was not created (not supported by this machine?)",
1479                         nd->name ? nd->name : "anonymous",
1480                         nd->model ? nd->model : "unspecified");
1481         }
1482     }
1483 }
1484 
1485 static int net_init_client(void *dummy, QemuOpts *opts, Error **errp)
1486 {
1487     return net_client_init(opts, false, errp);
1488 }
1489 
1490 static int net_init_netdev(void *dummy, QemuOpts *opts, Error **errp)
1491 {
1492     return net_client_init(opts, true, errp);
1493 }
1494 
1495 /* For the convenience "--nic" parameter */
1496 static int net_param_nic(void *dummy, QemuOpts *opts, Error **errp)
1497 {
1498     char *mac, *nd_id;
1499     int idx, ret;
1500     NICInfo *ni;
1501     const char *type;
1502 
1503     type = qemu_opt_get(opts, "type");
1504     if (type && g_str_equal(type, "none")) {
1505         return 0;    /* Nothing to do, default_net is cleared in vl.c */
1506     }
1507 
1508     idx = nic_get_free_idx();
1509     if (idx == -1 || nb_nics >= MAX_NICS) {
1510         error_setg(errp, "no more on-board/default NIC slots available");
1511         return -1;
1512     }
1513 
1514     if (!type) {
1515         qemu_opt_set(opts, "type", "user", &error_abort);
1516     }
1517 
1518     ni = &nd_table[idx];
1519     memset(ni, 0, sizeof(*ni));
1520     ni->model = qemu_opt_get_del(opts, "model");
1521 
1522     /* Create an ID if the user did not specify one */
1523     nd_id = g_strdup(qemu_opts_id(opts));
1524     if (!nd_id) {
1525         nd_id = g_strdup_printf("__org.qemu.nic%i\n", idx);
1526         qemu_opts_set_id(opts, nd_id);
1527     }
1528 
1529     /* Handle MAC address */
1530     mac = qemu_opt_get_del(opts, "mac");
1531     if (mac) {
1532         ret = net_parse_macaddr(ni->macaddr.a, mac);
1533         g_free(mac);
1534         if (ret) {
1535             error_setg(errp, "invalid syntax for ethernet address");
1536             goto out;
1537         }
1538         if (is_multicast_ether_addr(ni->macaddr.a)) {
1539             error_setg(errp, "NIC cannot have multicast MAC address");
1540             ret = -1;
1541             goto out;
1542         }
1543     }
1544     qemu_macaddr_default_if_unset(&ni->macaddr);
1545 
1546     ret = net_client_init(opts, true, errp);
1547     if (ret == 0) {
1548         ni->netdev = qemu_find_netdev(nd_id);
1549         ni->used = true;
1550         nb_nics++;
1551     }
1552 
1553 out:
1554     g_free(nd_id);
1555     return ret;
1556 }
1557 
1558 int net_init_clients(Error **errp)
1559 {
1560     net_change_state_entry =
1561         qemu_add_vm_change_state_handler(net_vm_change_state_handler, NULL);
1562 
1563     QTAILQ_INIT(&net_clients);
1564 
1565     if (qemu_opts_foreach(qemu_find_opts("netdev"),
1566                           net_init_netdev, NULL, errp)) {
1567         return -1;
1568     }
1569 
1570     if (qemu_opts_foreach(qemu_find_opts("nic"), net_param_nic, NULL, errp)) {
1571         return -1;
1572     }
1573 
1574     if (qemu_opts_foreach(qemu_find_opts("net"), net_init_client, NULL, errp)) {
1575         return -1;
1576     }
1577 
1578     return 0;
1579 }
1580 
1581 int net_client_parse(QemuOptsList *opts_list, const char *optarg)
1582 {
1583     if (!qemu_opts_parse_noisily(opts_list, optarg, true)) {
1584         return -1;
1585     }
1586 
1587     return 0;
1588 }
1589 
1590 /* From FreeBSD */
1591 /* XXX: optimize */
1592 uint32_t net_crc32(const uint8_t *p, int len)
1593 {
1594     uint32_t crc;
1595     int carry, i, j;
1596     uint8_t b;
1597 
1598     crc = 0xffffffff;
1599     for (i = 0; i < len; i++) {
1600         b = *p++;
1601         for (j = 0; j < 8; j++) {
1602             carry = ((crc & 0x80000000L) ? 1 : 0) ^ (b & 0x01);
1603             crc <<= 1;
1604             b >>= 1;
1605             if (carry) {
1606                 crc = ((crc ^ POLYNOMIAL_BE) | carry);
1607             }
1608         }
1609     }
1610 
1611     return crc;
1612 }
1613 
1614 uint32_t net_crc32_le(const uint8_t *p, int len)
1615 {
1616     uint32_t crc;
1617     int carry, i, j;
1618     uint8_t b;
1619 
1620     crc = 0xffffffff;
1621     for (i = 0; i < len; i++) {
1622         b = *p++;
1623         for (j = 0; j < 8; j++) {
1624             carry = (crc & 0x1) ^ (b & 0x01);
1625             crc >>= 1;
1626             b >>= 1;
1627             if (carry) {
1628                 crc ^= POLYNOMIAL_LE;
1629             }
1630         }
1631     }
1632 
1633     return crc;
1634 }
1635 
1636 QemuOptsList qemu_netdev_opts = {
1637     .name = "netdev",
1638     .implied_opt_name = "type",
1639     .head = QTAILQ_HEAD_INITIALIZER(qemu_netdev_opts.head),
1640     .desc = {
1641         /*
1642          * no elements => accept any params
1643          * validation will happen later
1644          */
1645         { /* end of list */ }
1646     },
1647 };
1648 
1649 QemuOptsList qemu_nic_opts = {
1650     .name = "nic",
1651     .implied_opt_name = "type",
1652     .head = QTAILQ_HEAD_INITIALIZER(qemu_nic_opts.head),
1653     .desc = {
1654         /*
1655          * no elements => accept any params
1656          * validation will happen later
1657          */
1658         { /* end of list */ }
1659     },
1660 };
1661 
1662 QemuOptsList qemu_net_opts = {
1663     .name = "net",
1664     .implied_opt_name = "type",
1665     .head = QTAILQ_HEAD_INITIALIZER(qemu_net_opts.head),
1666     .desc = {
1667         /*
1668          * no elements => accept any params
1669          * validation will happen later
1670          */
1671         { /* end of list */ }
1672     },
1673 };
1674 
1675 void net_socket_rs_init(SocketReadState *rs,
1676                         SocketReadStateFinalize *finalize,
1677                         bool vnet_hdr)
1678 {
1679     rs->state = 0;
1680     rs->vnet_hdr = vnet_hdr;
1681     rs->index = 0;
1682     rs->packet_len = 0;
1683     rs->vnet_hdr_len = 0;
1684     memset(rs->buf, 0, sizeof(rs->buf));
1685     rs->finalize = finalize;
1686 }
1687 
1688 /*
1689  * Returns
1690  * 0: success
1691  * -1: error occurs
1692  */
1693 int net_fill_rstate(SocketReadState *rs, const uint8_t *buf, int size)
1694 {
1695     unsigned int l;
1696 
1697     while (size > 0) {
1698         /* Reassemble a packet from the network.
1699          * 0 = getting length.
1700          * 1 = getting vnet header length.
1701          * 2 = getting data.
1702          */
1703         switch (rs->state) {
1704         case 0:
1705             l = 4 - rs->index;
1706             if (l > size) {
1707                 l = size;
1708             }
1709             memcpy(rs->buf + rs->index, buf, l);
1710             buf += l;
1711             size -= l;
1712             rs->index += l;
1713             if (rs->index == 4) {
1714                 /* got length */
1715                 rs->packet_len = ntohl(*(uint32_t *)rs->buf);
1716                 rs->index = 0;
1717                 if (rs->vnet_hdr) {
1718                     rs->state = 1;
1719                 } else {
1720                     rs->state = 2;
1721                     rs->vnet_hdr_len = 0;
1722                 }
1723             }
1724             break;
1725         case 1:
1726             l = 4 - rs->index;
1727             if (l > size) {
1728                 l = size;
1729             }
1730             memcpy(rs->buf + rs->index, buf, l);
1731             buf += l;
1732             size -= l;
1733             rs->index += l;
1734             if (rs->index == 4) {
1735                 /* got vnet header length */
1736                 rs->vnet_hdr_len = ntohl(*(uint32_t *)rs->buf);
1737                 rs->index = 0;
1738                 rs->state = 2;
1739             }
1740             break;
1741         case 2:
1742             l = rs->packet_len - rs->index;
1743             if (l > size) {
1744                 l = size;
1745             }
1746             if (rs->index + l <= sizeof(rs->buf)) {
1747                 memcpy(rs->buf + rs->index, buf, l);
1748             } else {
1749                 fprintf(stderr, "serious error: oversized packet received,"
1750                     "connection terminated.\n");
1751                 rs->index = rs->state = 0;
1752                 return -1;
1753             }
1754 
1755             rs->index += l;
1756             buf += l;
1757             size -= l;
1758             if (rs->index >= rs->packet_len) {
1759                 rs->index = 0;
1760                 rs->state = 0;
1761                 assert(rs->finalize);
1762                 rs->finalize(rs);
1763             }
1764             break;
1765         }
1766     }
1767 
1768     assert(size == 0);
1769     return 0;
1770 }
1771