xref: /openbmc/qemu/net/net.c (revision ac12b601)
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 #include "qemu-common.h"
27 
28 #include "net/net.h"
29 #include "clients.h"
30 #include "hub.h"
31 #include "hw/qdev-properties.h"
32 #include "net/slirp.h"
33 #include "net/eth.h"
34 #include "util.h"
35 
36 #include "monitor/monitor.h"
37 #include "qemu/help_option.h"
38 #include "qapi/qapi-commands-net.h"
39 #include "qapi/qapi-visit-net.h"
40 #include "qapi/qmp/qdict.h"
41 #include "qapi/qmp/qerror.h"
42 #include "qemu/error-report.h"
43 #include "qemu/sockets.h"
44 #include "qemu/cutils.h"
45 #include "qemu/config-file.h"
46 #include "qemu/ctype.h"
47 #include "qemu/id.h"
48 #include "qemu/iov.h"
49 #include "qemu/qemu-print.h"
50 #include "qemu/main-loop.h"
51 #include "qemu/option.h"
52 #include "qapi/error.h"
53 #include "qapi/opts-visitor.h"
54 #include "sysemu/runstate.h"
55 #include "net/filter.h"
56 #include "qapi/string-output-visitor.h"
57 
58 /* Net bridge is currently not supported for W32. */
59 #if !defined(_WIN32)
60 # define CONFIG_NET_BRIDGE
61 #endif
62 
63 static VMChangeStateEntry *net_change_state_entry;
64 static QTAILQ_HEAD(, NetClientState) net_clients;
65 
66 /***********************************************************/
67 /* network device redirectors */
68 
69 int parse_host_port(struct sockaddr_in *saddr, const char *str,
70                     Error **errp)
71 {
72     gchar **substrings;
73     struct hostent *he;
74     const char *addr, *p, *r;
75     int port, ret = 0;
76 
77     substrings = g_strsplit(str, ":", 2);
78     if (!substrings || !substrings[0] || !substrings[1]) {
79         error_setg(errp, "host address '%s' doesn't contain ':' "
80                    "separating host from port", str);
81         ret = -1;
82         goto out;
83     }
84 
85     addr = substrings[0];
86     p = substrings[1];
87 
88     saddr->sin_family = AF_INET;
89     if (addr[0] == '\0') {
90         saddr->sin_addr.s_addr = 0;
91     } else {
92         if (qemu_isdigit(addr[0])) {
93             if (!inet_aton(addr, &saddr->sin_addr)) {
94                 error_setg(errp, "host address '%s' is not a valid "
95                            "IPv4 address", addr);
96                 ret = -1;
97                 goto out;
98             }
99         } else {
100             he = gethostbyname(addr);
101             if (he == NULL) {
102                 error_setg(errp, "can't resolve host address '%s'", addr);
103                 ret = -1;
104                 goto out;
105             }
106             saddr->sin_addr = *(struct in_addr *)he->h_addr;
107         }
108     }
109     port = strtol(p, (char **)&r, 0);
110     if (r == p) {
111         error_setg(errp, "port number '%s' is invalid", p);
112         ret = -1;
113         goto out;
114     }
115     saddr->sin_port = htons(port);
116 
117 out:
118     g_strfreev(substrings);
119     return ret;
120 }
121 
122 char *qemu_mac_strdup_printf(const uint8_t *macaddr)
123 {
124     return g_strdup_printf("%.2x:%.2x:%.2x:%.2x:%.2x:%.2x",
125                            macaddr[0], macaddr[1], macaddr[2],
126                            macaddr[3], macaddr[4], macaddr[5]);
127 }
128 
129 void qemu_format_nic_info_str(NetClientState *nc, uint8_t macaddr[6])
130 {
131     snprintf(nc->info_str, sizeof(nc->info_str),
132              "model=%s,macaddr=%02x:%02x:%02x:%02x:%02x:%02x",
133              nc->model,
134              macaddr[0], macaddr[1], macaddr[2],
135              macaddr[3], macaddr[4], macaddr[5]);
136 }
137 
138 static int mac_table[256] = {0};
139 
140 static void qemu_macaddr_set_used(MACAddr *macaddr)
141 {
142     int index;
143 
144     for (index = 0x56; index < 0xFF; index++) {
145         if (macaddr->a[5] == index) {
146             mac_table[index]++;
147         }
148     }
149 }
150 
151 static void qemu_macaddr_set_free(MACAddr *macaddr)
152 {
153     int index;
154     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
155 
156     if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
157         return;
158     }
159     for (index = 0x56; index < 0xFF; index++) {
160         if (macaddr->a[5] == index) {
161             mac_table[index]--;
162         }
163     }
164 }
165 
166 static int qemu_macaddr_get_free(void)
167 {
168     int index;
169 
170     for (index = 0x56; index < 0xFF; index++) {
171         if (mac_table[index] == 0) {
172             return index;
173         }
174     }
175 
176     return -1;
177 }
178 
179 void qemu_macaddr_default_if_unset(MACAddr *macaddr)
180 {
181     static const MACAddr zero = { .a = { 0,0,0,0,0,0 } };
182     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
183 
184     if (memcmp(macaddr, &zero, sizeof(zero)) != 0) {
185         if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
186             return;
187         } else {
188             qemu_macaddr_set_used(macaddr);
189             return;
190         }
191     }
192 
193     macaddr->a[0] = 0x52;
194     macaddr->a[1] = 0x54;
195     macaddr->a[2] = 0x00;
196     macaddr->a[3] = 0x12;
197     macaddr->a[4] = 0x34;
198     macaddr->a[5] = qemu_macaddr_get_free();
199     qemu_macaddr_set_used(macaddr);
200 }
201 
202 /**
203  * Generate a name for net client
204  *
205  * Only net clients created with the legacy -net option and NICs need this.
206  */
207 static char *assign_name(NetClientState *nc1, const char *model)
208 {
209     NetClientState *nc;
210     int id = 0;
211 
212     QTAILQ_FOREACH(nc, &net_clients, next) {
213         if (nc == nc1) {
214             continue;
215         }
216         if (strcmp(nc->model, model) == 0) {
217             id++;
218         }
219     }
220 
221     return g_strdup_printf("%s.%d", model, id);
222 }
223 
224 static void qemu_net_client_destructor(NetClientState *nc)
225 {
226     g_free(nc);
227 }
228 static ssize_t qemu_deliver_packet_iov(NetClientState *sender,
229                                        unsigned flags,
230                                        const struct iovec *iov,
231                                        int iovcnt,
232                                        void *opaque);
233 
234 static void qemu_net_client_setup(NetClientState *nc,
235                                   NetClientInfo *info,
236                                   NetClientState *peer,
237                                   const char *model,
238                                   const char *name,
239                                   NetClientDestructor *destructor)
240 {
241     nc->info = info;
242     nc->model = g_strdup(model);
243     if (name) {
244         nc->name = g_strdup(name);
245     } else {
246         nc->name = assign_name(nc, model);
247     }
248 
249     if (peer) {
250         assert(!peer->peer);
251         nc->peer = peer;
252         peer->peer = nc;
253     }
254     QTAILQ_INSERT_TAIL(&net_clients, nc, next);
255 
256     nc->incoming_queue = qemu_new_net_queue(qemu_deliver_packet_iov, nc);
257     nc->destructor = destructor;
258     QTAILQ_INIT(&nc->filters);
259 }
260 
261 NetClientState *qemu_new_net_client(NetClientInfo *info,
262                                     NetClientState *peer,
263                                     const char *model,
264                                     const char *name)
265 {
266     NetClientState *nc;
267 
268     assert(info->size >= sizeof(NetClientState));
269 
270     nc = g_malloc0(info->size);
271     qemu_net_client_setup(nc, info, peer, model, name,
272                           qemu_net_client_destructor);
273 
274     return nc;
275 }
276 
277 NICState *qemu_new_nic(NetClientInfo *info,
278                        NICConf *conf,
279                        const char *model,
280                        const char *name,
281                        void *opaque)
282 {
283     NetClientState **peers = conf->peers.ncs;
284     NICState *nic;
285     int i, queues = MAX(1, conf->peers.queues);
286 
287     assert(info->type == NET_CLIENT_DRIVER_NIC);
288     assert(info->size >= sizeof(NICState));
289 
290     nic = g_malloc0(info->size + sizeof(NetClientState) * queues);
291     nic->ncs = (void *)nic + info->size;
292     nic->conf = conf;
293     nic->opaque = opaque;
294 
295     for (i = 0; i < queues; i++) {
296         qemu_net_client_setup(&nic->ncs[i], info, peers[i], model, name,
297                               NULL);
298         nic->ncs[i].queue_index = i;
299     }
300 
301     return nic;
302 }
303 
304 NetClientState *qemu_get_subqueue(NICState *nic, int queue_index)
305 {
306     return nic->ncs + queue_index;
307 }
308 
309 NetClientState *qemu_get_queue(NICState *nic)
310 {
311     return qemu_get_subqueue(nic, 0);
312 }
313 
314 NICState *qemu_get_nic(NetClientState *nc)
315 {
316     NetClientState *nc0 = nc - nc->queue_index;
317 
318     return (NICState *)((void *)nc0 - nc->info->size);
319 }
320 
321 void *qemu_get_nic_opaque(NetClientState *nc)
322 {
323     NICState *nic = qemu_get_nic(nc);
324 
325     return nic->opaque;
326 }
327 
328 NetClientState *qemu_get_peer(NetClientState *nc, int queue_index)
329 {
330     assert(nc != NULL);
331     NetClientState *ncs = nc + queue_index;
332     return ncs->peer;
333 }
334 
335 static void qemu_cleanup_net_client(NetClientState *nc)
336 {
337     QTAILQ_REMOVE(&net_clients, nc, next);
338 
339     if (nc->info->cleanup) {
340         nc->info->cleanup(nc);
341     }
342 }
343 
344 static void qemu_free_net_client(NetClientState *nc)
345 {
346     if (nc->incoming_queue) {
347         qemu_del_net_queue(nc->incoming_queue);
348     }
349     if (nc->peer) {
350         nc->peer->peer = NULL;
351     }
352     g_free(nc->name);
353     g_free(nc->model);
354     if (nc->destructor) {
355         nc->destructor(nc);
356     }
357 }
358 
359 void qemu_del_net_client(NetClientState *nc)
360 {
361     NetClientState *ncs[MAX_QUEUE_NUM];
362     int queues, i;
363     NetFilterState *nf, *next;
364 
365     assert(nc->info->type != NET_CLIENT_DRIVER_NIC);
366 
367     /* If the NetClientState belongs to a multiqueue backend, we will change all
368      * other NetClientStates also.
369      */
370     queues = qemu_find_net_clients_except(nc->name, ncs,
371                                           NET_CLIENT_DRIVER_NIC,
372                                           MAX_QUEUE_NUM);
373     assert(queues != 0);
374 
375     QTAILQ_FOREACH_SAFE(nf, &nc->filters, next, next) {
376         object_unparent(OBJECT(nf));
377     }
378 
379     /* If there is a peer NIC, delete and cleanup client, but do not free. */
380     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
381         NICState *nic = qemu_get_nic(nc->peer);
382         if (nic->peer_deleted) {
383             return;
384         }
385         nic->peer_deleted = true;
386 
387         for (i = 0; i < queues; i++) {
388             ncs[i]->peer->link_down = true;
389         }
390 
391         if (nc->peer->info->link_status_changed) {
392             nc->peer->info->link_status_changed(nc->peer);
393         }
394 
395         for (i = 0; i < queues; i++) {
396             qemu_cleanup_net_client(ncs[i]);
397         }
398 
399         return;
400     }
401 
402     for (i = 0; i < queues; i++) {
403         qemu_cleanup_net_client(ncs[i]);
404         qemu_free_net_client(ncs[i]);
405     }
406 }
407 
408 void qemu_del_nic(NICState *nic)
409 {
410     int i, queues = MAX(nic->conf->peers.queues, 1);
411 
412     qemu_macaddr_set_free(&nic->conf->macaddr);
413 
414     for (i = 0; i < queues; i++) {
415         NetClientState *nc = qemu_get_subqueue(nic, i);
416         /* If this is a peer NIC and peer has already been deleted, free it now. */
417         if (nic->peer_deleted) {
418             qemu_free_net_client(nc->peer);
419         } else if (nc->peer) {
420             /* if there are RX packets pending, complete them */
421             qemu_purge_queued_packets(nc->peer);
422         }
423     }
424 
425     for (i = queues - 1; i >= 0; i--) {
426         NetClientState *nc = qemu_get_subqueue(nic, i);
427 
428         qemu_cleanup_net_client(nc);
429         qemu_free_net_client(nc);
430     }
431 
432     g_free(nic);
433 }
434 
435 void qemu_foreach_nic(qemu_nic_foreach func, void *opaque)
436 {
437     NetClientState *nc;
438 
439     QTAILQ_FOREACH(nc, &net_clients, next) {
440         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
441             if (nc->queue_index == 0) {
442                 func(qemu_get_nic(nc), opaque);
443             }
444         }
445     }
446 }
447 
448 bool qemu_has_ufo(NetClientState *nc)
449 {
450     if (!nc || !nc->info->has_ufo) {
451         return false;
452     }
453 
454     return nc->info->has_ufo(nc);
455 }
456 
457 bool qemu_has_vnet_hdr(NetClientState *nc)
458 {
459     if (!nc || !nc->info->has_vnet_hdr) {
460         return false;
461     }
462 
463     return nc->info->has_vnet_hdr(nc);
464 }
465 
466 bool qemu_has_vnet_hdr_len(NetClientState *nc, int len)
467 {
468     if (!nc || !nc->info->has_vnet_hdr_len) {
469         return false;
470     }
471 
472     return nc->info->has_vnet_hdr_len(nc, len);
473 }
474 
475 void qemu_using_vnet_hdr(NetClientState *nc, bool enable)
476 {
477     if (!nc || !nc->info->using_vnet_hdr) {
478         return;
479     }
480 
481     nc->info->using_vnet_hdr(nc, enable);
482 }
483 
484 void qemu_set_offload(NetClientState *nc, int csum, int tso4, int tso6,
485                           int ecn, int ufo)
486 {
487     if (!nc || !nc->info->set_offload) {
488         return;
489     }
490 
491     nc->info->set_offload(nc, csum, tso4, tso6, ecn, ufo);
492 }
493 
494 void qemu_set_vnet_hdr_len(NetClientState *nc, int len)
495 {
496     if (!nc || !nc->info->set_vnet_hdr_len) {
497         return;
498     }
499 
500     nc->vnet_hdr_len = len;
501     nc->info->set_vnet_hdr_len(nc, len);
502 }
503 
504 int qemu_set_vnet_le(NetClientState *nc, bool is_le)
505 {
506 #ifdef HOST_WORDS_BIGENDIAN
507     if (!nc || !nc->info->set_vnet_le) {
508         return -ENOSYS;
509     }
510 
511     return nc->info->set_vnet_le(nc, is_le);
512 #else
513     return 0;
514 #endif
515 }
516 
517 int qemu_set_vnet_be(NetClientState *nc, bool is_be)
518 {
519 #ifdef HOST_WORDS_BIGENDIAN
520     return 0;
521 #else
522     if (!nc || !nc->info->set_vnet_be) {
523         return -ENOSYS;
524     }
525 
526     return nc->info->set_vnet_be(nc, is_be);
527 #endif
528 }
529 
530 int qemu_can_receive_packet(NetClientState *nc)
531 {
532     if (nc->receive_disabled) {
533         return 0;
534     } else if (nc->info->can_receive &&
535                !nc->info->can_receive(nc)) {
536         return 0;
537     }
538     return 1;
539 }
540 
541 int qemu_can_send_packet(NetClientState *sender)
542 {
543     int vm_running = runstate_is_running();
544 
545     if (!vm_running) {
546         return 0;
547     }
548 
549     if (!sender->peer) {
550         return 1;
551     }
552 
553     return qemu_can_receive_packet(sender->peer);
554 }
555 
556 static ssize_t filter_receive_iov(NetClientState *nc,
557                                   NetFilterDirection direction,
558                                   NetClientState *sender,
559                                   unsigned flags,
560                                   const struct iovec *iov,
561                                   int iovcnt,
562                                   NetPacketSent *sent_cb)
563 {
564     ssize_t ret = 0;
565     NetFilterState *nf = NULL;
566 
567     if (direction == NET_FILTER_DIRECTION_TX) {
568         QTAILQ_FOREACH(nf, &nc->filters, next) {
569             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
570                                          iovcnt, sent_cb);
571             if (ret) {
572                 return ret;
573             }
574         }
575     } else {
576         QTAILQ_FOREACH_REVERSE(nf, &nc->filters, next) {
577             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
578                                          iovcnt, sent_cb);
579             if (ret) {
580                 return ret;
581             }
582         }
583     }
584 
585     return ret;
586 }
587 
588 static ssize_t filter_receive(NetClientState *nc,
589                               NetFilterDirection direction,
590                               NetClientState *sender,
591                               unsigned flags,
592                               const uint8_t *data,
593                               size_t size,
594                               NetPacketSent *sent_cb)
595 {
596     struct iovec iov = {
597         .iov_base = (void *)data,
598         .iov_len = size
599     };
600 
601     return filter_receive_iov(nc, direction, sender, flags, &iov, 1, sent_cb);
602 }
603 
604 void qemu_purge_queued_packets(NetClientState *nc)
605 {
606     if (!nc->peer) {
607         return;
608     }
609 
610     qemu_net_queue_purge(nc->peer->incoming_queue, nc);
611 }
612 
613 void qemu_flush_or_purge_queued_packets(NetClientState *nc, bool purge)
614 {
615     nc->receive_disabled = 0;
616 
617     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_HUBPORT) {
618         if (net_hub_flush(nc->peer)) {
619             qemu_notify_event();
620         }
621     }
622     if (qemu_net_queue_flush(nc->incoming_queue)) {
623         /* We emptied the queue successfully, signal to the IO thread to repoll
624          * the file descriptor (for tap, for example).
625          */
626         qemu_notify_event();
627     } else if (purge) {
628         /* Unable to empty the queue, purge remaining packets */
629         qemu_net_queue_purge(nc->incoming_queue, nc->peer);
630     }
631 }
632 
633 void qemu_flush_queued_packets(NetClientState *nc)
634 {
635     qemu_flush_or_purge_queued_packets(nc, false);
636 }
637 
638 static ssize_t qemu_send_packet_async_with_flags(NetClientState *sender,
639                                                  unsigned flags,
640                                                  const uint8_t *buf, int size,
641                                                  NetPacketSent *sent_cb)
642 {
643     NetQueue *queue;
644     int ret;
645 
646 #ifdef DEBUG_NET
647     printf("qemu_send_packet_async:\n");
648     qemu_hexdump(stdout, "net", buf, size);
649 #endif
650 
651     if (sender->link_down || !sender->peer) {
652         return size;
653     }
654 
655     /* Let filters handle the packet first */
656     ret = filter_receive(sender, NET_FILTER_DIRECTION_TX,
657                          sender, flags, buf, size, sent_cb);
658     if (ret) {
659         return ret;
660     }
661 
662     ret = filter_receive(sender->peer, NET_FILTER_DIRECTION_RX,
663                          sender, flags, buf, size, sent_cb);
664     if (ret) {
665         return ret;
666     }
667 
668     queue = sender->peer->incoming_queue;
669 
670     return qemu_net_queue_send(queue, sender, flags, buf, size, sent_cb);
671 }
672 
673 ssize_t qemu_send_packet_async(NetClientState *sender,
674                                const uint8_t *buf, int size,
675                                NetPacketSent *sent_cb)
676 {
677     return qemu_send_packet_async_with_flags(sender, QEMU_NET_PACKET_FLAG_NONE,
678                                              buf, size, sent_cb);
679 }
680 
681 ssize_t qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size)
682 {
683     return qemu_send_packet_async(nc, buf, size, NULL);
684 }
685 
686 ssize_t qemu_receive_packet(NetClientState *nc, const uint8_t *buf, int size)
687 {
688     if (!qemu_can_receive_packet(nc)) {
689         return 0;
690     }
691 
692     return qemu_net_queue_receive(nc->incoming_queue, buf, size);
693 }
694 
695 ssize_t qemu_receive_packet_iov(NetClientState *nc, const struct iovec *iov,
696                                 int iovcnt)
697 {
698     if (!qemu_can_receive_packet(nc)) {
699         return 0;
700     }
701 
702     return qemu_net_queue_receive_iov(nc->incoming_queue, iov, iovcnt);
703 }
704 
705 ssize_t qemu_send_packet_raw(NetClientState *nc, const uint8_t *buf, int size)
706 {
707     return qemu_send_packet_async_with_flags(nc, QEMU_NET_PACKET_FLAG_RAW,
708                                              buf, size, NULL);
709 }
710 
711 static ssize_t nc_sendv_compat(NetClientState *nc, const struct iovec *iov,
712                                int iovcnt, unsigned flags)
713 {
714     uint8_t *buf = NULL;
715     uint8_t *buffer;
716     size_t offset;
717     ssize_t ret;
718 
719     if (iovcnt == 1) {
720         buffer = iov[0].iov_base;
721         offset = iov[0].iov_len;
722     } else {
723         offset = iov_size(iov, iovcnt);
724         if (offset > NET_BUFSIZE) {
725             return -1;
726         }
727         buf = g_malloc(offset);
728         buffer = buf;
729         offset = iov_to_buf(iov, iovcnt, 0, buf, offset);
730     }
731 
732     if (flags & QEMU_NET_PACKET_FLAG_RAW && nc->info->receive_raw) {
733         ret = nc->info->receive_raw(nc, buffer, offset);
734     } else {
735         ret = nc->info->receive(nc, buffer, offset);
736     }
737 
738     g_free(buf);
739     return ret;
740 }
741 
742 static ssize_t qemu_deliver_packet_iov(NetClientState *sender,
743                                        unsigned flags,
744                                        const struct iovec *iov,
745                                        int iovcnt,
746                                        void *opaque)
747 {
748     NetClientState *nc = opaque;
749     int ret;
750 
751 
752     if (nc->link_down) {
753         return iov_size(iov, iovcnt);
754     }
755 
756     if (nc->receive_disabled) {
757         return 0;
758     }
759 
760     if (nc->info->receive_iov && !(flags & QEMU_NET_PACKET_FLAG_RAW)) {
761         ret = nc->info->receive_iov(nc, iov, iovcnt);
762     } else {
763         ret = nc_sendv_compat(nc, iov, iovcnt, flags);
764     }
765 
766     if (ret == 0) {
767         nc->receive_disabled = 1;
768     }
769 
770     return ret;
771 }
772 
773 ssize_t qemu_sendv_packet_async(NetClientState *sender,
774                                 const struct iovec *iov, int iovcnt,
775                                 NetPacketSent *sent_cb)
776 {
777     NetQueue *queue;
778     size_t size = iov_size(iov, iovcnt);
779     int ret;
780 
781     if (size > NET_BUFSIZE) {
782         return size;
783     }
784 
785     if (sender->link_down || !sender->peer) {
786         return size;
787     }
788 
789     /* Let filters handle the packet first */
790     ret = filter_receive_iov(sender, NET_FILTER_DIRECTION_TX, sender,
791                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
792     if (ret) {
793         return ret;
794     }
795 
796     ret = filter_receive_iov(sender->peer, NET_FILTER_DIRECTION_RX, sender,
797                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
798     if (ret) {
799         return ret;
800     }
801 
802     queue = sender->peer->incoming_queue;
803 
804     return qemu_net_queue_send_iov(queue, sender,
805                                    QEMU_NET_PACKET_FLAG_NONE,
806                                    iov, iovcnt, sent_cb);
807 }
808 
809 ssize_t
810 qemu_sendv_packet(NetClientState *nc, const struct iovec *iov, int iovcnt)
811 {
812     return qemu_sendv_packet_async(nc, iov, iovcnt, NULL);
813 }
814 
815 NetClientState *qemu_find_netdev(const char *id)
816 {
817     NetClientState *nc;
818 
819     QTAILQ_FOREACH(nc, &net_clients, next) {
820         if (nc->info->type == NET_CLIENT_DRIVER_NIC)
821             continue;
822         if (!strcmp(nc->name, id)) {
823             return nc;
824         }
825     }
826 
827     return NULL;
828 }
829 
830 int qemu_find_net_clients_except(const char *id, NetClientState **ncs,
831                                  NetClientDriver type, int max)
832 {
833     NetClientState *nc;
834     int ret = 0;
835 
836     QTAILQ_FOREACH(nc, &net_clients, next) {
837         if (nc->info->type == type) {
838             continue;
839         }
840         if (!id || !strcmp(nc->name, id)) {
841             if (ret < max) {
842                 ncs[ret] = nc;
843             }
844             ret++;
845         }
846     }
847 
848     return ret;
849 }
850 
851 static int nic_get_free_idx(void)
852 {
853     int index;
854 
855     for (index = 0; index < MAX_NICS; index++)
856         if (!nd_table[index].used)
857             return index;
858     return -1;
859 }
860 
861 int qemu_show_nic_models(const char *arg, const char *const *models)
862 {
863     int i;
864 
865     if (!arg || !is_help_option(arg)) {
866         return 0;
867     }
868 
869     printf("Supported NIC models:\n");
870     for (i = 0 ; models[i]; i++) {
871         printf("%s\n", models[i]);
872     }
873     return 1;
874 }
875 
876 void qemu_check_nic_model(NICInfo *nd, const char *model)
877 {
878     const char *models[2];
879 
880     models[0] = model;
881     models[1] = NULL;
882 
883     if (qemu_show_nic_models(nd->model, models))
884         exit(0);
885     if (qemu_find_nic_model(nd, models, model) < 0)
886         exit(1);
887 }
888 
889 int qemu_find_nic_model(NICInfo *nd, const char * const *models,
890                         const char *default_model)
891 {
892     int i;
893 
894     if (!nd->model)
895         nd->model = g_strdup(default_model);
896 
897     for (i = 0 ; models[i]; i++) {
898         if (strcmp(nd->model, models[i]) == 0)
899             return i;
900     }
901 
902     error_report("Unsupported NIC model: %s", nd->model);
903     return -1;
904 }
905 
906 static int net_init_nic(const Netdev *netdev, const char *name,
907                         NetClientState *peer, Error **errp)
908 {
909     int idx;
910     NICInfo *nd;
911     const NetLegacyNicOptions *nic;
912 
913     assert(netdev->type == NET_CLIENT_DRIVER_NIC);
914     nic = &netdev->u.nic;
915 
916     idx = nic_get_free_idx();
917     if (idx == -1 || nb_nics >= MAX_NICS) {
918         error_setg(errp, "too many NICs");
919         return -1;
920     }
921 
922     nd = &nd_table[idx];
923 
924     memset(nd, 0, sizeof(*nd));
925 
926     if (nic->has_netdev) {
927         nd->netdev = qemu_find_netdev(nic->netdev);
928         if (!nd->netdev) {
929             error_setg(errp, "netdev '%s' not found", nic->netdev);
930             return -1;
931         }
932     } else {
933         assert(peer);
934         nd->netdev = peer;
935     }
936     nd->name = g_strdup(name);
937     if (nic->has_model) {
938         nd->model = g_strdup(nic->model);
939     }
940     if (nic->has_addr) {
941         nd->devaddr = g_strdup(nic->addr);
942     }
943 
944     if (nic->has_macaddr &&
945         net_parse_macaddr(nd->macaddr.a, nic->macaddr) < 0) {
946         error_setg(errp, "invalid syntax for ethernet address");
947         return -1;
948     }
949     if (nic->has_macaddr &&
950         is_multicast_ether_addr(nd->macaddr.a)) {
951         error_setg(errp,
952                    "NIC cannot have multicast MAC address (odd 1st byte)");
953         return -1;
954     }
955     qemu_macaddr_default_if_unset(&nd->macaddr);
956 
957     if (nic->has_vectors) {
958         if (nic->vectors > 0x7ffffff) {
959             error_setg(errp, "invalid # of vectors: %"PRIu32, nic->vectors);
960             return -1;
961         }
962         nd->nvectors = nic->vectors;
963     } else {
964         nd->nvectors = DEV_NVECTORS_UNSPECIFIED;
965     }
966 
967     nd->used = 1;
968     nb_nics++;
969 
970     return idx;
971 }
972 
973 
974 static int (* const net_client_init_fun[NET_CLIENT_DRIVER__MAX])(
975     const Netdev *netdev,
976     const char *name,
977     NetClientState *peer, Error **errp) = {
978         [NET_CLIENT_DRIVER_NIC]       = net_init_nic,
979 #ifdef CONFIG_SLIRP
980         [NET_CLIENT_DRIVER_USER]      = net_init_slirp,
981 #endif
982         [NET_CLIENT_DRIVER_TAP]       = net_init_tap,
983         [NET_CLIENT_DRIVER_SOCKET]    = net_init_socket,
984 #ifdef CONFIG_VDE
985         [NET_CLIENT_DRIVER_VDE]       = net_init_vde,
986 #endif
987 #ifdef CONFIG_NETMAP
988         [NET_CLIENT_DRIVER_NETMAP]    = net_init_netmap,
989 #endif
990 #ifdef CONFIG_NET_BRIDGE
991         [NET_CLIENT_DRIVER_BRIDGE]    = net_init_bridge,
992 #endif
993         [NET_CLIENT_DRIVER_HUBPORT]   = net_init_hubport,
994 #ifdef CONFIG_VHOST_NET_USER
995         [NET_CLIENT_DRIVER_VHOST_USER] = net_init_vhost_user,
996 #endif
997 #ifdef CONFIG_VHOST_NET_VDPA
998         [NET_CLIENT_DRIVER_VHOST_VDPA] = net_init_vhost_vdpa,
999 #endif
1000 #ifdef CONFIG_L2TPV3
1001         [NET_CLIENT_DRIVER_L2TPV3]    = net_init_l2tpv3,
1002 #endif
1003 };
1004 
1005 
1006 static int net_client_init1(const Netdev *netdev, bool is_netdev, Error **errp)
1007 {
1008     NetClientState *peer = NULL;
1009     NetClientState *nc;
1010 
1011     if (is_netdev) {
1012         if (netdev->type == NET_CLIENT_DRIVER_NIC ||
1013             !net_client_init_fun[netdev->type]) {
1014             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
1015                        "a netdev backend type");
1016             return -1;
1017         }
1018     } else {
1019         if (netdev->type == NET_CLIENT_DRIVER_NONE) {
1020             return 0; /* nothing to do */
1021         }
1022         if (netdev->type == NET_CLIENT_DRIVER_HUBPORT ||
1023             !net_client_init_fun[netdev->type]) {
1024             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
1025                        "a net backend type (maybe it is not compiled "
1026                        "into this binary)");
1027             return -1;
1028         }
1029 
1030         /* Do not add to a hub if it's a nic with a netdev= parameter. */
1031         if (netdev->type != NET_CLIENT_DRIVER_NIC ||
1032             !netdev->u.nic.has_netdev) {
1033             peer = net_hub_add_port(0, NULL, NULL);
1034         }
1035     }
1036 
1037     nc = qemu_find_netdev(netdev->id);
1038     if (nc) {
1039         error_setg(errp, "Duplicate ID '%s'", netdev->id);
1040         return -1;
1041     }
1042 
1043     if (net_client_init_fun[netdev->type](netdev, netdev->id, peer, errp) < 0) {
1044         /* FIXME drop when all init functions store an Error */
1045         if (errp && !*errp) {
1046             error_setg(errp, "Device '%s' could not be initialized",
1047                        NetClientDriver_str(netdev->type));
1048         }
1049         return -1;
1050     }
1051 
1052     if (is_netdev) {
1053         nc = qemu_find_netdev(netdev->id);
1054         assert(nc);
1055         nc->is_netdev = true;
1056     }
1057 
1058     return 0;
1059 }
1060 
1061 void show_netdevs(void)
1062 {
1063     int idx;
1064     const char *available_netdevs[] = {
1065         "socket",
1066         "hubport",
1067         "tap",
1068 #ifdef CONFIG_SLIRP
1069         "user",
1070 #endif
1071 #ifdef CONFIG_L2TPV3
1072         "l2tpv3",
1073 #endif
1074 #ifdef CONFIG_VDE
1075         "vde",
1076 #endif
1077 #ifdef CONFIG_NET_BRIDGE
1078         "bridge",
1079 #endif
1080 #ifdef CONFIG_NETMAP
1081         "netmap",
1082 #endif
1083 #ifdef CONFIG_POSIX
1084         "vhost-user",
1085 #endif
1086 #ifdef CONFIG_VHOST_VDPA
1087         "vhost-vdpa",
1088 #endif
1089     };
1090 
1091     qemu_printf("Available netdev backend types:\n");
1092     for (idx = 0; idx < ARRAY_SIZE(available_netdevs); idx++) {
1093         qemu_printf("%s\n", available_netdevs[idx]);
1094     }
1095 }
1096 
1097 static int net_client_init(QemuOpts *opts, bool is_netdev, Error **errp)
1098 {
1099     gchar **substrings = NULL;
1100     Netdev *object = NULL;
1101     int ret = -1;
1102     Visitor *v = opts_visitor_new(opts);
1103 
1104     /* Parse convenience option format ip6-net=fec0::0[/64] */
1105     const char *ip6_net = qemu_opt_get(opts, "ipv6-net");
1106 
1107     if (ip6_net) {
1108         char *prefix_addr;
1109         unsigned long prefix_len = 64; /* Default 64bit prefix length. */
1110 
1111         substrings = g_strsplit(ip6_net, "/", 2);
1112         if (!substrings || !substrings[0]) {
1113             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "ipv6-net",
1114                        "a valid IPv6 prefix");
1115             goto out;
1116         }
1117 
1118         prefix_addr = substrings[0];
1119 
1120         /* Handle user-specified prefix length. */
1121         if (substrings[1] &&
1122             qemu_strtoul(substrings[1], NULL, 10, &prefix_len))
1123         {
1124             error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1125                        "ipv6-prefixlen", "a number");
1126             goto out;
1127         }
1128 
1129         qemu_opt_set(opts, "ipv6-prefix", prefix_addr, &error_abort);
1130         qemu_opt_set_number(opts, "ipv6-prefixlen", prefix_len,
1131                             &error_abort);
1132         qemu_opt_unset(opts, "ipv6-net");
1133     }
1134 
1135     /* Create an ID for -net if the user did not specify one */
1136     if (!is_netdev && !qemu_opts_id(opts)) {
1137         qemu_opts_set_id(opts, id_generate(ID_NET));
1138     }
1139 
1140     if (visit_type_Netdev(v, NULL, &object, errp)) {
1141         ret = net_client_init1(object, is_netdev, errp);
1142     }
1143 
1144     qapi_free_Netdev(object);
1145 
1146 out:
1147     g_strfreev(substrings);
1148     visit_free(v);
1149     return ret;
1150 }
1151 
1152 void netdev_add(QemuOpts *opts, Error **errp)
1153 {
1154     net_client_init(opts, true, errp);
1155 }
1156 
1157 void qmp_netdev_add(Netdev *netdev, Error **errp)
1158 {
1159     if (!id_wellformed(netdev->id)) {
1160         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "id", "an identifier");
1161         return;
1162     }
1163 
1164     net_client_init1(netdev, true, errp);
1165 }
1166 
1167 void qmp_netdev_del(const char *id, Error **errp)
1168 {
1169     NetClientState *nc;
1170     QemuOpts *opts;
1171 
1172     nc = qemu_find_netdev(id);
1173     if (!nc) {
1174         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1175                   "Device '%s' not found", id);
1176         return;
1177     }
1178 
1179     if (!nc->is_netdev) {
1180         error_setg(errp, "Device '%s' is not a netdev", id);
1181         return;
1182     }
1183 
1184     qemu_del_net_client(nc);
1185 
1186     /*
1187      * Wart: we need to delete the QemuOpts associated with netdevs
1188      * created via CLI or HMP, to avoid bogus "Duplicate ID" errors in
1189      * HMP netdev_add.
1190      */
1191     opts = qemu_opts_find(qemu_find_opts("netdev"), id);
1192     if (opts) {
1193         qemu_opts_del(opts);
1194     }
1195 }
1196 
1197 static void netfilter_print_info(Monitor *mon, NetFilterState *nf)
1198 {
1199     char *str;
1200     ObjectProperty *prop;
1201     ObjectPropertyIterator iter;
1202     Visitor *v;
1203 
1204     /* generate info str */
1205     object_property_iter_init(&iter, OBJECT(nf));
1206     while ((prop = object_property_iter_next(&iter))) {
1207         if (!strcmp(prop->name, "type")) {
1208             continue;
1209         }
1210         v = string_output_visitor_new(false, &str);
1211         object_property_get(OBJECT(nf), prop->name, v, NULL);
1212         visit_complete(v, &str);
1213         visit_free(v);
1214         monitor_printf(mon, ",%s=%s", prop->name, str);
1215         g_free(str);
1216     }
1217     monitor_printf(mon, "\n");
1218 }
1219 
1220 void print_net_client(Monitor *mon, NetClientState *nc)
1221 {
1222     NetFilterState *nf;
1223 
1224     monitor_printf(mon, "%s: index=%d,type=%s,%s\n", nc->name,
1225                    nc->queue_index,
1226                    NetClientDriver_str(nc->info->type),
1227                    nc->info_str);
1228     if (!QTAILQ_EMPTY(&nc->filters)) {
1229         monitor_printf(mon, "filters:\n");
1230     }
1231     QTAILQ_FOREACH(nf, &nc->filters, next) {
1232         monitor_printf(mon, "  - %s: type=%s",
1233                        object_get_canonical_path_component(OBJECT(nf)),
1234                        object_get_typename(OBJECT(nf)));
1235         netfilter_print_info(mon, nf);
1236     }
1237 }
1238 
1239 RxFilterInfoList *qmp_query_rx_filter(bool has_name, const char *name,
1240                                       Error **errp)
1241 {
1242     NetClientState *nc;
1243     RxFilterInfoList *filter_list = NULL, **tail = &filter_list;
1244 
1245     QTAILQ_FOREACH(nc, &net_clients, next) {
1246         RxFilterInfo *info;
1247 
1248         if (has_name && strcmp(nc->name, name) != 0) {
1249             continue;
1250         }
1251 
1252         /* only query rx-filter information of NIC */
1253         if (nc->info->type != NET_CLIENT_DRIVER_NIC) {
1254             if (has_name) {
1255                 error_setg(errp, "net client(%s) isn't a NIC", name);
1256                 assert(!filter_list);
1257                 return NULL;
1258             }
1259             continue;
1260         }
1261 
1262         /* only query information on queue 0 since the info is per nic,
1263          * not per queue
1264          */
1265         if (nc->queue_index != 0)
1266             continue;
1267 
1268         if (nc->info->query_rx_filter) {
1269             info = nc->info->query_rx_filter(nc);
1270             QAPI_LIST_APPEND(tail, info);
1271         } else if (has_name) {
1272             error_setg(errp, "net client(%s) doesn't support"
1273                        " rx-filter querying", name);
1274             assert(!filter_list);
1275             return NULL;
1276         }
1277 
1278         if (has_name) {
1279             break;
1280         }
1281     }
1282 
1283     if (filter_list == NULL && has_name) {
1284         error_setg(errp, "invalid net client name: %s", name);
1285     }
1286 
1287     return filter_list;
1288 }
1289 
1290 void hmp_info_network(Monitor *mon, const QDict *qdict)
1291 {
1292     NetClientState *nc, *peer;
1293     NetClientDriver type;
1294 
1295     net_hub_info(mon);
1296 
1297     QTAILQ_FOREACH(nc, &net_clients, next) {
1298         peer = nc->peer;
1299         type = nc->info->type;
1300 
1301         /* Skip if already printed in hub info */
1302         if (net_hub_id_for_client(nc, NULL) == 0) {
1303             continue;
1304         }
1305 
1306         if (!peer || type == NET_CLIENT_DRIVER_NIC) {
1307             print_net_client(mon, nc);
1308         } /* else it's a netdev connected to a NIC, printed with the NIC */
1309         if (peer && type == NET_CLIENT_DRIVER_NIC) {
1310             monitor_printf(mon, " \\ ");
1311             print_net_client(mon, peer);
1312         }
1313     }
1314 }
1315 
1316 void colo_notify_filters_event(int event, Error **errp)
1317 {
1318     NetClientState *nc;
1319     NetFilterState *nf;
1320     NetFilterClass *nfc = NULL;
1321     Error *local_err = NULL;
1322 
1323     QTAILQ_FOREACH(nc, &net_clients, next) {
1324         QTAILQ_FOREACH(nf, &nc->filters, next) {
1325             nfc = NETFILTER_GET_CLASS(OBJECT(nf));
1326             nfc->handle_event(nf, event, &local_err);
1327             if (local_err) {
1328                 error_propagate(errp, local_err);
1329                 return;
1330             }
1331         }
1332     }
1333 }
1334 
1335 void qmp_set_link(const char *name, bool up, Error **errp)
1336 {
1337     NetClientState *ncs[MAX_QUEUE_NUM];
1338     NetClientState *nc;
1339     int queues, i;
1340 
1341     queues = qemu_find_net_clients_except(name, ncs,
1342                                           NET_CLIENT_DRIVER__MAX,
1343                                           MAX_QUEUE_NUM);
1344 
1345     if (queues == 0) {
1346         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1347                   "Device '%s' not found", name);
1348         return;
1349     }
1350     nc = ncs[0];
1351 
1352     for (i = 0; i < queues; i++) {
1353         ncs[i]->link_down = !up;
1354     }
1355 
1356     if (nc->info->link_status_changed) {
1357         nc->info->link_status_changed(nc);
1358     }
1359 
1360     if (nc->peer) {
1361         /* Change peer link only if the peer is NIC and then notify peer.
1362          * If the peer is a HUBPORT or a backend, we do not change the
1363          * link status.
1364          *
1365          * This behavior is compatible with qemu hubs where there could be
1366          * multiple clients that can still communicate with each other in
1367          * disconnected mode. For now maintain this compatibility.
1368          */
1369         if (nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
1370             for (i = 0; i < queues; i++) {
1371                 ncs[i]->peer->link_down = !up;
1372             }
1373         }
1374         if (nc->peer->info->link_status_changed) {
1375             nc->peer->info->link_status_changed(nc->peer);
1376         }
1377     }
1378 }
1379 
1380 static void net_vm_change_state_handler(void *opaque, bool running,
1381                                         RunState state)
1382 {
1383     NetClientState *nc;
1384     NetClientState *tmp;
1385 
1386     QTAILQ_FOREACH_SAFE(nc, &net_clients, next, tmp) {
1387         if (running) {
1388             /* Flush queued packets and wake up backends. */
1389             if (nc->peer && qemu_can_send_packet(nc)) {
1390                 qemu_flush_queued_packets(nc->peer);
1391             }
1392         } else {
1393             /* Complete all queued packets, to guarantee we don't modify
1394              * state later when VM is not running.
1395              */
1396             qemu_flush_or_purge_queued_packets(nc, true);
1397         }
1398     }
1399 }
1400 
1401 void net_cleanup(void)
1402 {
1403     NetClientState *nc;
1404 
1405     /* We may del multiple entries during qemu_del_net_client(),
1406      * so QTAILQ_FOREACH_SAFE() is also not safe here.
1407      */
1408     while (!QTAILQ_EMPTY(&net_clients)) {
1409         nc = QTAILQ_FIRST(&net_clients);
1410         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
1411             qemu_del_nic(qemu_get_nic(nc));
1412         } else {
1413             qemu_del_net_client(nc);
1414         }
1415     }
1416 
1417     qemu_del_vm_change_state_handler(net_change_state_entry);
1418 }
1419 
1420 void net_check_clients(void)
1421 {
1422     NetClientState *nc;
1423     int i;
1424 
1425     net_hub_check_clients();
1426 
1427     QTAILQ_FOREACH(nc, &net_clients, next) {
1428         if (!nc->peer) {
1429             warn_report("%s %s has no peer",
1430                         nc->info->type == NET_CLIENT_DRIVER_NIC
1431                         ? "nic" : "netdev",
1432                         nc->name);
1433         }
1434     }
1435 
1436     /* Check that all NICs requested via -net nic actually got created.
1437      * NICs created via -device don't need to be checked here because
1438      * they are always instantiated.
1439      */
1440     for (i = 0; i < MAX_NICS; i++) {
1441         NICInfo *nd = &nd_table[i];
1442         if (nd->used && !nd->instantiated) {
1443             warn_report("requested NIC (%s, model %s) "
1444                         "was not created (not supported by this machine?)",
1445                         nd->name ? nd->name : "anonymous",
1446                         nd->model ? nd->model : "unspecified");
1447         }
1448     }
1449 }
1450 
1451 static int net_init_client(void *dummy, QemuOpts *opts, Error **errp)
1452 {
1453     return net_client_init(opts, false, errp);
1454 }
1455 
1456 static int net_init_netdev(void *dummy, QemuOpts *opts, Error **errp)
1457 {
1458     const char *type = qemu_opt_get(opts, "type");
1459 
1460     if (type && is_help_option(type)) {
1461         show_netdevs();
1462         exit(0);
1463     }
1464     return net_client_init(opts, true, errp);
1465 }
1466 
1467 /* For the convenience "--nic" parameter */
1468 static int net_param_nic(void *dummy, QemuOpts *opts, Error **errp)
1469 {
1470     char *mac, *nd_id;
1471     int idx, ret;
1472     NICInfo *ni;
1473     const char *type;
1474 
1475     type = qemu_opt_get(opts, "type");
1476     if (type && g_str_equal(type, "none")) {
1477         return 0;    /* Nothing to do, default_net is cleared in vl.c */
1478     }
1479 
1480     idx = nic_get_free_idx();
1481     if (idx == -1 || nb_nics >= MAX_NICS) {
1482         error_setg(errp, "no more on-board/default NIC slots available");
1483         return -1;
1484     }
1485 
1486     if (!type) {
1487         qemu_opt_set(opts, "type", "user", &error_abort);
1488     }
1489 
1490     ni = &nd_table[idx];
1491     memset(ni, 0, sizeof(*ni));
1492     ni->model = qemu_opt_get_del(opts, "model");
1493 
1494     /* Create an ID if the user did not specify one */
1495     nd_id = g_strdup(qemu_opts_id(opts));
1496     if (!nd_id) {
1497         nd_id = id_generate(ID_NET);
1498         qemu_opts_set_id(opts, nd_id);
1499     }
1500 
1501     /* Handle MAC address */
1502     mac = qemu_opt_get_del(opts, "mac");
1503     if (mac) {
1504         ret = net_parse_macaddr(ni->macaddr.a, mac);
1505         g_free(mac);
1506         if (ret) {
1507             error_setg(errp, "invalid syntax for ethernet address");
1508             goto out;
1509         }
1510         if (is_multicast_ether_addr(ni->macaddr.a)) {
1511             error_setg(errp, "NIC cannot have multicast MAC address");
1512             ret = -1;
1513             goto out;
1514         }
1515     }
1516     qemu_macaddr_default_if_unset(&ni->macaddr);
1517 
1518     ret = net_client_init(opts, true, errp);
1519     if (ret == 0) {
1520         ni->netdev = qemu_find_netdev(nd_id);
1521         ni->used = true;
1522         nb_nics++;
1523     }
1524 
1525 out:
1526     g_free(nd_id);
1527     return ret;
1528 }
1529 
1530 int net_init_clients(Error **errp)
1531 {
1532     net_change_state_entry =
1533         qemu_add_vm_change_state_handler(net_vm_change_state_handler, NULL);
1534 
1535     QTAILQ_INIT(&net_clients);
1536 
1537     if (qemu_opts_foreach(qemu_find_opts("netdev"),
1538                           net_init_netdev, NULL, errp)) {
1539         return -1;
1540     }
1541 
1542     if (qemu_opts_foreach(qemu_find_opts("nic"), net_param_nic, NULL, errp)) {
1543         return -1;
1544     }
1545 
1546     if (qemu_opts_foreach(qemu_find_opts("net"), net_init_client, NULL, errp)) {
1547         return -1;
1548     }
1549 
1550     return 0;
1551 }
1552 
1553 int net_client_parse(QemuOptsList *opts_list, const char *optarg)
1554 {
1555     if (!qemu_opts_parse_noisily(opts_list, optarg, true)) {
1556         return -1;
1557     }
1558 
1559     return 0;
1560 }
1561 
1562 /* From FreeBSD */
1563 /* XXX: optimize */
1564 uint32_t net_crc32(const uint8_t *p, int len)
1565 {
1566     uint32_t crc;
1567     int carry, i, j;
1568     uint8_t b;
1569 
1570     crc = 0xffffffff;
1571     for (i = 0; i < len; i++) {
1572         b = *p++;
1573         for (j = 0; j < 8; j++) {
1574             carry = ((crc & 0x80000000L) ? 1 : 0) ^ (b & 0x01);
1575             crc <<= 1;
1576             b >>= 1;
1577             if (carry) {
1578                 crc = ((crc ^ POLYNOMIAL_BE) | carry);
1579             }
1580         }
1581     }
1582 
1583     return crc;
1584 }
1585 
1586 uint32_t net_crc32_le(const uint8_t *p, int len)
1587 {
1588     uint32_t crc;
1589     int carry, i, j;
1590     uint8_t b;
1591 
1592     crc = 0xffffffff;
1593     for (i = 0; i < len; i++) {
1594         b = *p++;
1595         for (j = 0; j < 8; j++) {
1596             carry = (crc & 0x1) ^ (b & 0x01);
1597             crc >>= 1;
1598             b >>= 1;
1599             if (carry) {
1600                 crc ^= POLYNOMIAL_LE;
1601             }
1602         }
1603     }
1604 
1605     return crc;
1606 }
1607 
1608 QemuOptsList qemu_netdev_opts = {
1609     .name = "netdev",
1610     .implied_opt_name = "type",
1611     .head = QTAILQ_HEAD_INITIALIZER(qemu_netdev_opts.head),
1612     .desc = {
1613         /*
1614          * no elements => accept any params
1615          * validation will happen later
1616          */
1617         { /* end of list */ }
1618     },
1619 };
1620 
1621 QemuOptsList qemu_nic_opts = {
1622     .name = "nic",
1623     .implied_opt_name = "type",
1624     .head = QTAILQ_HEAD_INITIALIZER(qemu_nic_opts.head),
1625     .desc = {
1626         /*
1627          * no elements => accept any params
1628          * validation will happen later
1629          */
1630         { /* end of list */ }
1631     },
1632 };
1633 
1634 QemuOptsList qemu_net_opts = {
1635     .name = "net",
1636     .implied_opt_name = "type",
1637     .head = QTAILQ_HEAD_INITIALIZER(qemu_net_opts.head),
1638     .desc = {
1639         /*
1640          * no elements => accept any params
1641          * validation will happen later
1642          */
1643         { /* end of list */ }
1644     },
1645 };
1646 
1647 void net_socket_rs_init(SocketReadState *rs,
1648                         SocketReadStateFinalize *finalize,
1649                         bool vnet_hdr)
1650 {
1651     rs->state = 0;
1652     rs->vnet_hdr = vnet_hdr;
1653     rs->index = 0;
1654     rs->packet_len = 0;
1655     rs->vnet_hdr_len = 0;
1656     memset(rs->buf, 0, sizeof(rs->buf));
1657     rs->finalize = finalize;
1658 }
1659 
1660 /*
1661  * Returns
1662  * 0: success
1663  * -1: error occurs
1664  */
1665 int net_fill_rstate(SocketReadState *rs, const uint8_t *buf, int size)
1666 {
1667     unsigned int l;
1668 
1669     while (size > 0) {
1670         /* Reassemble a packet from the network.
1671          * 0 = getting length.
1672          * 1 = getting vnet header length.
1673          * 2 = getting data.
1674          */
1675         switch (rs->state) {
1676         case 0:
1677             l = 4 - rs->index;
1678             if (l > size) {
1679                 l = size;
1680             }
1681             memcpy(rs->buf + rs->index, buf, l);
1682             buf += l;
1683             size -= l;
1684             rs->index += l;
1685             if (rs->index == 4) {
1686                 /* got length */
1687                 rs->packet_len = ntohl(*(uint32_t *)rs->buf);
1688                 rs->index = 0;
1689                 if (rs->vnet_hdr) {
1690                     rs->state = 1;
1691                 } else {
1692                     rs->state = 2;
1693                     rs->vnet_hdr_len = 0;
1694                 }
1695             }
1696             break;
1697         case 1:
1698             l = 4 - rs->index;
1699             if (l > size) {
1700                 l = size;
1701             }
1702             memcpy(rs->buf + rs->index, buf, l);
1703             buf += l;
1704             size -= l;
1705             rs->index += l;
1706             if (rs->index == 4) {
1707                 /* got vnet header length */
1708                 rs->vnet_hdr_len = ntohl(*(uint32_t *)rs->buf);
1709                 rs->index = 0;
1710                 rs->state = 2;
1711             }
1712             break;
1713         case 2:
1714             l = rs->packet_len - rs->index;
1715             if (l > size) {
1716                 l = size;
1717             }
1718             if (rs->index + l <= sizeof(rs->buf)) {
1719                 memcpy(rs->buf + rs->index, buf, l);
1720             } else {
1721                 fprintf(stderr, "serious error: oversized packet received,"
1722                     "connection terminated.\n");
1723                 rs->index = rs->state = 0;
1724                 return -1;
1725             }
1726 
1727             rs->index += l;
1728             buf += l;
1729             size -= l;
1730             if (rs->index >= rs->packet_len) {
1731                 rs->index = 0;
1732                 rs->state = 0;
1733                 assert(rs->finalize);
1734                 rs->finalize(rs);
1735             }
1736             break;
1737         }
1738     }
1739 
1740     assert(size == 0);
1741     return 0;
1742 }
1743