xref: /openbmc/qemu/net/net.c (revision 65d1a2bd)
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/colo-compare.h"
56 #include "net/filter.h"
57 #include "qapi/string-output-visitor.h"
58 
59 /* Net bridge is currently not supported for W32. */
60 #if !defined(_WIN32)
61 # define CONFIG_NET_BRIDGE
62 #endif
63 
64 static VMChangeStateEntry *net_change_state_entry;
65 static QTAILQ_HEAD(, NetClientState) net_clients;
66 
67 /***********************************************************/
68 /* network device redirectors */
69 
70 int parse_host_port(struct sockaddr_in *saddr, const char *str,
71                     Error **errp)
72 {
73     gchar **substrings;
74     struct hostent *he;
75     const char *addr, *p, *r;
76     int port, ret = 0;
77 
78     substrings = g_strsplit(str, ":", 2);
79     if (!substrings || !substrings[0] || !substrings[1]) {
80         error_setg(errp, "host address '%s' doesn't contain ':' "
81                    "separating host from port", str);
82         ret = -1;
83         goto out;
84     }
85 
86     addr = substrings[0];
87     p = substrings[1];
88 
89     saddr->sin_family = AF_INET;
90     if (addr[0] == '\0') {
91         saddr->sin_addr.s_addr = 0;
92     } else {
93         if (qemu_isdigit(addr[0])) {
94             if (!inet_aton(addr, &saddr->sin_addr)) {
95                 error_setg(errp, "host address '%s' is not a valid "
96                            "IPv4 address", addr);
97                 ret = -1;
98                 goto out;
99             }
100         } else {
101             he = gethostbyname(addr);
102             if (he == NULL) {
103                 error_setg(errp, "can't resolve host address '%s'", addr);
104                 ret = -1;
105                 goto out;
106             }
107             saddr->sin_addr = *(struct in_addr *)he->h_addr;
108         }
109     }
110     port = strtol(p, (char **)&r, 0);
111     if (r == p) {
112         error_setg(errp, "port number '%s' is invalid", p);
113         ret = -1;
114         goto out;
115     }
116     saddr->sin_port = htons(port);
117 
118 out:
119     g_strfreev(substrings);
120     return ret;
121 }
122 
123 char *qemu_mac_strdup_printf(const uint8_t *macaddr)
124 {
125     return g_strdup_printf("%.2x:%.2x:%.2x:%.2x:%.2x:%.2x",
126                            macaddr[0], macaddr[1], macaddr[2],
127                            macaddr[3], macaddr[4], macaddr[5]);
128 }
129 
130 void qemu_format_nic_info_str(NetClientState *nc, uint8_t macaddr[6])
131 {
132     snprintf(nc->info_str, sizeof(nc->info_str),
133              "model=%s,macaddr=%02x:%02x:%02x:%02x:%02x:%02x",
134              nc->model,
135              macaddr[0], macaddr[1], macaddr[2],
136              macaddr[3], macaddr[4], macaddr[5]);
137 }
138 
139 static int mac_table[256] = {0};
140 
141 static void qemu_macaddr_set_used(MACAddr *macaddr)
142 {
143     int index;
144 
145     for (index = 0x56; index < 0xFF; index++) {
146         if (macaddr->a[5] == index) {
147             mac_table[index]++;
148         }
149     }
150 }
151 
152 static void qemu_macaddr_set_free(MACAddr *macaddr)
153 {
154     int index;
155     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
156 
157     if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
158         return;
159     }
160     for (index = 0x56; index < 0xFF; index++) {
161         if (macaddr->a[5] == index) {
162             mac_table[index]--;
163         }
164     }
165 }
166 
167 static int qemu_macaddr_get_free(void)
168 {
169     int index;
170 
171     for (index = 0x56; index < 0xFF; index++) {
172         if (mac_table[index] == 0) {
173             return index;
174         }
175     }
176 
177     return -1;
178 }
179 
180 void qemu_macaddr_default_if_unset(MACAddr *macaddr)
181 {
182     static const MACAddr zero = { .a = { 0,0,0,0,0,0 } };
183     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
184 
185     if (memcmp(macaddr, &zero, sizeof(zero)) != 0) {
186         if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
187             return;
188         } else {
189             qemu_macaddr_set_used(macaddr);
190             return;
191         }
192     }
193 
194     macaddr->a[0] = 0x52;
195     macaddr->a[1] = 0x54;
196     macaddr->a[2] = 0x00;
197     macaddr->a[3] = 0x12;
198     macaddr->a[4] = 0x34;
199     macaddr->a[5] = qemu_macaddr_get_free();
200     qemu_macaddr_set_used(macaddr);
201 }
202 
203 /**
204  * Generate a name for net client
205  *
206  * Only net clients created with the legacy -net option and NICs need this.
207  */
208 static char *assign_name(NetClientState *nc1, const char *model)
209 {
210     NetClientState *nc;
211     int id = 0;
212 
213     QTAILQ_FOREACH(nc, &net_clients, next) {
214         if (nc == nc1) {
215             continue;
216         }
217         if (strcmp(nc->model, model) == 0) {
218             id++;
219         }
220     }
221 
222     return g_strdup_printf("%s.%d", model, id);
223 }
224 
225 static void qemu_net_client_destructor(NetClientState *nc)
226 {
227     g_free(nc);
228 }
229 static ssize_t qemu_deliver_packet_iov(NetClientState *sender,
230                                        unsigned flags,
231                                        const struct iovec *iov,
232                                        int iovcnt,
233                                        void *opaque);
234 
235 static void qemu_net_client_setup(NetClientState *nc,
236                                   NetClientInfo *info,
237                                   NetClientState *peer,
238                                   const char *model,
239                                   const char *name,
240                                   NetClientDestructor *destructor)
241 {
242     nc->info = info;
243     nc->model = g_strdup(model);
244     if (name) {
245         nc->name = g_strdup(name);
246     } else {
247         nc->name = assign_name(nc, model);
248     }
249 
250     if (peer) {
251         assert(!peer->peer);
252         nc->peer = peer;
253         peer->peer = nc;
254     }
255     QTAILQ_INSERT_TAIL(&net_clients, nc, next);
256 
257     nc->incoming_queue = qemu_new_net_queue(qemu_deliver_packet_iov, nc);
258     nc->destructor = destructor;
259     QTAILQ_INIT(&nc->filters);
260 }
261 
262 NetClientState *qemu_new_net_client(NetClientInfo *info,
263                                     NetClientState *peer,
264                                     const char *model,
265                                     const char *name)
266 {
267     NetClientState *nc;
268 
269     assert(info->size >= sizeof(NetClientState));
270 
271     nc = g_malloc0(info->size);
272     qemu_net_client_setup(nc, info, peer, model, name,
273                           qemu_net_client_destructor);
274 
275     return nc;
276 }
277 
278 NICState *qemu_new_nic(NetClientInfo *info,
279                        NICConf *conf,
280                        const char *model,
281                        const char *name,
282                        void *opaque)
283 {
284     NetClientState **peers = conf->peers.ncs;
285     NICState *nic;
286     int i, queues = MAX(1, conf->peers.queues);
287 
288     assert(info->type == NET_CLIENT_DRIVER_NIC);
289     assert(info->size >= sizeof(NICState));
290 
291     nic = g_malloc0(info->size + sizeof(NetClientState) * queues);
292     nic->ncs = (void *)nic + info->size;
293     nic->conf = conf;
294     nic->opaque = opaque;
295 
296     for (i = 0; i < queues; i++) {
297         qemu_net_client_setup(&nic->ncs[i], info, peers[i], model, name,
298                               NULL);
299         nic->ncs[i].queue_index = i;
300     }
301 
302     return nic;
303 }
304 
305 NetClientState *qemu_get_subqueue(NICState *nic, int queue_index)
306 {
307     return nic->ncs + queue_index;
308 }
309 
310 NetClientState *qemu_get_queue(NICState *nic)
311 {
312     return qemu_get_subqueue(nic, 0);
313 }
314 
315 NICState *qemu_get_nic(NetClientState *nc)
316 {
317     NetClientState *nc0 = nc - nc->queue_index;
318 
319     return (NICState *)((void *)nc0 - nc->info->size);
320 }
321 
322 void *qemu_get_nic_opaque(NetClientState *nc)
323 {
324     NICState *nic = qemu_get_nic(nc);
325 
326     return nic->opaque;
327 }
328 
329 NetClientState *qemu_get_peer(NetClientState *nc, int queue_index)
330 {
331     assert(nc != NULL);
332     NetClientState *ncs = nc + queue_index;
333     return ncs->peer;
334 }
335 
336 static void qemu_cleanup_net_client(NetClientState *nc)
337 {
338     QTAILQ_REMOVE(&net_clients, nc, next);
339 
340     if (nc->info->cleanup) {
341         nc->info->cleanup(nc);
342     }
343 }
344 
345 static void qemu_free_net_client(NetClientState *nc)
346 {
347     if (nc->incoming_queue) {
348         qemu_del_net_queue(nc->incoming_queue);
349     }
350     if (nc->peer) {
351         nc->peer->peer = NULL;
352     }
353     g_free(nc->name);
354     g_free(nc->model);
355     if (nc->destructor) {
356         nc->destructor(nc);
357     }
358 }
359 
360 void qemu_del_net_client(NetClientState *nc)
361 {
362     NetClientState *ncs[MAX_QUEUE_NUM];
363     int queues, i;
364     NetFilterState *nf, *next;
365 
366     assert(nc->info->type != NET_CLIENT_DRIVER_NIC);
367 
368     /* If the NetClientState belongs to a multiqueue backend, we will change all
369      * other NetClientStates also.
370      */
371     queues = qemu_find_net_clients_except(nc->name, ncs,
372                                           NET_CLIENT_DRIVER_NIC,
373                                           MAX_QUEUE_NUM);
374     assert(queues != 0);
375 
376     QTAILQ_FOREACH_SAFE(nf, &nc->filters, next, next) {
377         object_unparent(OBJECT(nf));
378     }
379 
380     /* If there is a peer NIC, delete and cleanup client, but do not free. */
381     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
382         NICState *nic = qemu_get_nic(nc->peer);
383         if (nic->peer_deleted) {
384             return;
385         }
386         nic->peer_deleted = true;
387 
388         for (i = 0; i < queues; i++) {
389             ncs[i]->peer->link_down = true;
390         }
391 
392         if (nc->peer->info->link_status_changed) {
393             nc->peer->info->link_status_changed(nc->peer);
394         }
395 
396         for (i = 0; i < queues; i++) {
397             qemu_cleanup_net_client(ncs[i]);
398         }
399 
400         return;
401     }
402 
403     for (i = 0; i < queues; i++) {
404         qemu_cleanup_net_client(ncs[i]);
405         qemu_free_net_client(ncs[i]);
406     }
407 }
408 
409 void qemu_del_nic(NICState *nic)
410 {
411     int i, queues = MAX(nic->conf->peers.queues, 1);
412 
413     qemu_macaddr_set_free(&nic->conf->macaddr);
414 
415     for (i = 0; i < queues; i++) {
416         NetClientState *nc = qemu_get_subqueue(nic, i);
417         /* If this is a peer NIC and peer has already been deleted, free it now. */
418         if (nic->peer_deleted) {
419             qemu_free_net_client(nc->peer);
420         } else if (nc->peer) {
421             /* if there are RX packets pending, complete them */
422             qemu_purge_queued_packets(nc->peer);
423         }
424     }
425 
426     for (i = queues - 1; i >= 0; i--) {
427         NetClientState *nc = qemu_get_subqueue(nic, i);
428 
429         qemu_cleanup_net_client(nc);
430         qemu_free_net_client(nc);
431     }
432 
433     g_free(nic);
434 }
435 
436 void qemu_foreach_nic(qemu_nic_foreach func, void *opaque)
437 {
438     NetClientState *nc;
439 
440     QTAILQ_FOREACH(nc, &net_clients, next) {
441         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
442             if (nc->queue_index == 0) {
443                 func(qemu_get_nic(nc), opaque);
444             }
445         }
446     }
447 }
448 
449 bool qemu_has_ufo(NetClientState *nc)
450 {
451     if (!nc || !nc->info->has_ufo) {
452         return false;
453     }
454 
455     return nc->info->has_ufo(nc);
456 }
457 
458 bool qemu_has_vnet_hdr(NetClientState *nc)
459 {
460     if (!nc || !nc->info->has_vnet_hdr) {
461         return false;
462     }
463 
464     return nc->info->has_vnet_hdr(nc);
465 }
466 
467 bool qemu_has_vnet_hdr_len(NetClientState *nc, int len)
468 {
469     if (!nc || !nc->info->has_vnet_hdr_len) {
470         return false;
471     }
472 
473     return nc->info->has_vnet_hdr_len(nc, len);
474 }
475 
476 void qemu_using_vnet_hdr(NetClientState *nc, bool enable)
477 {
478     if (!nc || !nc->info->using_vnet_hdr) {
479         return;
480     }
481 
482     nc->info->using_vnet_hdr(nc, enable);
483 }
484 
485 void qemu_set_offload(NetClientState *nc, int csum, int tso4, int tso6,
486                           int ecn, int ufo)
487 {
488     if (!nc || !nc->info->set_offload) {
489         return;
490     }
491 
492     nc->info->set_offload(nc, csum, tso4, tso6, ecn, ufo);
493 }
494 
495 void qemu_set_vnet_hdr_len(NetClientState *nc, int len)
496 {
497     if (!nc || !nc->info->set_vnet_hdr_len) {
498         return;
499     }
500 
501     nc->vnet_hdr_len = len;
502     nc->info->set_vnet_hdr_len(nc, len);
503 }
504 
505 int qemu_set_vnet_le(NetClientState *nc, bool is_le)
506 {
507 #ifdef HOST_WORDS_BIGENDIAN
508     if (!nc || !nc->info->set_vnet_le) {
509         return -ENOSYS;
510     }
511 
512     return nc->info->set_vnet_le(nc, is_le);
513 #else
514     return 0;
515 #endif
516 }
517 
518 int qemu_set_vnet_be(NetClientState *nc, bool is_be)
519 {
520 #ifdef HOST_WORDS_BIGENDIAN
521     return 0;
522 #else
523     if (!nc || !nc->info->set_vnet_be) {
524         return -ENOSYS;
525     }
526 
527     return nc->info->set_vnet_be(nc, is_be);
528 #endif
529 }
530 
531 int qemu_can_receive_packet(NetClientState *nc)
532 {
533     if (nc->receive_disabled) {
534         return 0;
535     } else if (nc->info->can_receive &&
536                !nc->info->can_receive(nc)) {
537         return 0;
538     }
539     return 1;
540 }
541 
542 int qemu_can_send_packet(NetClientState *sender)
543 {
544     int vm_running = runstate_is_running();
545 
546     if (!vm_running) {
547         return 0;
548     }
549 
550     if (!sender->peer) {
551         return 1;
552     }
553 
554     return qemu_can_receive_packet(sender->peer);
555 }
556 
557 static ssize_t filter_receive_iov(NetClientState *nc,
558                                   NetFilterDirection direction,
559                                   NetClientState *sender,
560                                   unsigned flags,
561                                   const struct iovec *iov,
562                                   int iovcnt,
563                                   NetPacketSent *sent_cb)
564 {
565     ssize_t ret = 0;
566     NetFilterState *nf = NULL;
567 
568     if (direction == NET_FILTER_DIRECTION_TX) {
569         QTAILQ_FOREACH(nf, &nc->filters, next) {
570             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
571                                          iovcnt, sent_cb);
572             if (ret) {
573                 return ret;
574             }
575         }
576     } else {
577         QTAILQ_FOREACH_REVERSE(nf, &nc->filters, next) {
578             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
579                                          iovcnt, sent_cb);
580             if (ret) {
581                 return ret;
582             }
583         }
584     }
585 
586     return ret;
587 }
588 
589 static ssize_t filter_receive(NetClientState *nc,
590                               NetFilterDirection direction,
591                               NetClientState *sender,
592                               unsigned flags,
593                               const uint8_t *data,
594                               size_t size,
595                               NetPacketSent *sent_cb)
596 {
597     struct iovec iov = {
598         .iov_base = (void *)data,
599         .iov_len = size
600     };
601 
602     return filter_receive_iov(nc, direction, sender, flags, &iov, 1, sent_cb);
603 }
604 
605 void qemu_purge_queued_packets(NetClientState *nc)
606 {
607     if (!nc->peer) {
608         return;
609     }
610 
611     qemu_net_queue_purge(nc->peer->incoming_queue, nc);
612 }
613 
614 void qemu_flush_or_purge_queued_packets(NetClientState *nc, bool purge)
615 {
616     nc->receive_disabled = 0;
617 
618     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_HUBPORT) {
619         if (net_hub_flush(nc->peer)) {
620             qemu_notify_event();
621         }
622     }
623     if (qemu_net_queue_flush(nc->incoming_queue)) {
624         /* We emptied the queue successfully, signal to the IO thread to repoll
625          * the file descriptor (for tap, for example).
626          */
627         qemu_notify_event();
628     } else if (purge) {
629         /* Unable to empty the queue, purge remaining packets */
630         qemu_net_queue_purge(nc->incoming_queue, nc->peer);
631     }
632 }
633 
634 void qemu_flush_queued_packets(NetClientState *nc)
635 {
636     qemu_flush_or_purge_queued_packets(nc, false);
637 }
638 
639 static ssize_t qemu_send_packet_async_with_flags(NetClientState *sender,
640                                                  unsigned flags,
641                                                  const uint8_t *buf, int size,
642                                                  NetPacketSent *sent_cb)
643 {
644     NetQueue *queue;
645     int ret;
646 
647 #ifdef DEBUG_NET
648     printf("qemu_send_packet_async:\n");
649     qemu_hexdump(stdout, "net", buf, size);
650 #endif
651 
652     if (sender->link_down || !sender->peer) {
653         return size;
654     }
655 
656     /* Let filters handle the packet first */
657     ret = filter_receive(sender, NET_FILTER_DIRECTION_TX,
658                          sender, flags, buf, size, sent_cb);
659     if (ret) {
660         return ret;
661     }
662 
663     ret = filter_receive(sender->peer, NET_FILTER_DIRECTION_RX,
664                          sender, flags, buf, size, sent_cb);
665     if (ret) {
666         return ret;
667     }
668 
669     queue = sender->peer->incoming_queue;
670 
671     return qemu_net_queue_send(queue, sender, flags, buf, size, sent_cb);
672 }
673 
674 ssize_t qemu_send_packet_async(NetClientState *sender,
675                                const uint8_t *buf, int size,
676                                NetPacketSent *sent_cb)
677 {
678     return qemu_send_packet_async_with_flags(sender, QEMU_NET_PACKET_FLAG_NONE,
679                                              buf, size, sent_cb);
680 }
681 
682 ssize_t qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size)
683 {
684     return qemu_send_packet_async(nc, buf, size, NULL);
685 }
686 
687 ssize_t qemu_receive_packet(NetClientState *nc, const uint8_t *buf, int size)
688 {
689     if (!qemu_can_receive_packet(nc)) {
690         return 0;
691     }
692 
693     return qemu_net_queue_receive(nc->incoming_queue, buf, size);
694 }
695 
696 ssize_t qemu_receive_packet_iov(NetClientState *nc, const struct iovec *iov,
697                                 int iovcnt)
698 {
699     if (!qemu_can_receive_packet(nc)) {
700         return 0;
701     }
702 
703     return qemu_net_queue_receive_iov(nc->incoming_queue, iov, iovcnt);
704 }
705 
706 ssize_t qemu_send_packet_raw(NetClientState *nc, const uint8_t *buf, int size)
707 {
708     return qemu_send_packet_async_with_flags(nc, QEMU_NET_PACKET_FLAG_RAW,
709                                              buf, size, NULL);
710 }
711 
712 static ssize_t nc_sendv_compat(NetClientState *nc, const struct iovec *iov,
713                                int iovcnt, unsigned flags)
714 {
715     uint8_t *buf = NULL;
716     uint8_t *buffer;
717     size_t offset;
718     ssize_t ret;
719 
720     if (iovcnt == 1) {
721         buffer = iov[0].iov_base;
722         offset = iov[0].iov_len;
723     } else {
724         offset = iov_size(iov, iovcnt);
725         if (offset > NET_BUFSIZE) {
726             return -1;
727         }
728         buf = g_malloc(offset);
729         buffer = buf;
730         offset = iov_to_buf(iov, iovcnt, 0, buf, offset);
731     }
732 
733     if (flags & QEMU_NET_PACKET_FLAG_RAW && nc->info->receive_raw) {
734         ret = nc->info->receive_raw(nc, buffer, offset);
735     } else {
736         ret = nc->info->receive(nc, buffer, offset);
737     }
738 
739     g_free(buf);
740     return ret;
741 }
742 
743 static ssize_t qemu_deliver_packet_iov(NetClientState *sender,
744                                        unsigned flags,
745                                        const struct iovec *iov,
746                                        int iovcnt,
747                                        void *opaque)
748 {
749     NetClientState *nc = opaque;
750     int ret;
751 
752 
753     if (nc->link_down) {
754         return iov_size(iov, iovcnt);
755     }
756 
757     if (nc->receive_disabled) {
758         return 0;
759     }
760 
761     if (nc->info->receive_iov && !(flags & QEMU_NET_PACKET_FLAG_RAW)) {
762         ret = nc->info->receive_iov(nc, iov, iovcnt);
763     } else {
764         ret = nc_sendv_compat(nc, iov, iovcnt, flags);
765     }
766 
767     if (ret == 0) {
768         nc->receive_disabled = 1;
769     }
770 
771     return ret;
772 }
773 
774 ssize_t qemu_sendv_packet_async(NetClientState *sender,
775                                 const struct iovec *iov, int iovcnt,
776                                 NetPacketSent *sent_cb)
777 {
778     NetQueue *queue;
779     size_t size = iov_size(iov, iovcnt);
780     int ret;
781 
782     if (size > NET_BUFSIZE) {
783         return size;
784     }
785 
786     if (sender->link_down || !sender->peer) {
787         return size;
788     }
789 
790     /* Let filters handle the packet first */
791     ret = filter_receive_iov(sender, NET_FILTER_DIRECTION_TX, sender,
792                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
793     if (ret) {
794         return ret;
795     }
796 
797     ret = filter_receive_iov(sender->peer, NET_FILTER_DIRECTION_RX, sender,
798                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
799     if (ret) {
800         return ret;
801     }
802 
803     queue = sender->peer->incoming_queue;
804 
805     return qemu_net_queue_send_iov(queue, sender,
806                                    QEMU_NET_PACKET_FLAG_NONE,
807                                    iov, iovcnt, sent_cb);
808 }
809 
810 ssize_t
811 qemu_sendv_packet(NetClientState *nc, const struct iovec *iov, int iovcnt)
812 {
813     return qemu_sendv_packet_async(nc, iov, iovcnt, NULL);
814 }
815 
816 NetClientState *qemu_find_netdev(const char *id)
817 {
818     NetClientState *nc;
819 
820     QTAILQ_FOREACH(nc, &net_clients, next) {
821         if (nc->info->type == NET_CLIENT_DRIVER_NIC)
822             continue;
823         if (!strcmp(nc->name, id)) {
824             return nc;
825         }
826     }
827 
828     return NULL;
829 }
830 
831 int qemu_find_net_clients_except(const char *id, NetClientState **ncs,
832                                  NetClientDriver type, int max)
833 {
834     NetClientState *nc;
835     int ret = 0;
836 
837     QTAILQ_FOREACH(nc, &net_clients, next) {
838         if (nc->info->type == type) {
839             continue;
840         }
841         if (!id || !strcmp(nc->name, id)) {
842             if (ret < max) {
843                 ncs[ret] = nc;
844             }
845             ret++;
846         }
847     }
848 
849     return ret;
850 }
851 
852 static int nic_get_free_idx(void)
853 {
854     int index;
855 
856     for (index = 0; index < MAX_NICS; index++)
857         if (!nd_table[index].used)
858             return index;
859     return -1;
860 }
861 
862 int qemu_show_nic_models(const char *arg, const char *const *models)
863 {
864     int i;
865 
866     if (!arg || !is_help_option(arg)) {
867         return 0;
868     }
869 
870     printf("Supported NIC models:\n");
871     for (i = 0 ; models[i]; i++) {
872         printf("%s\n", models[i]);
873     }
874     return 1;
875 }
876 
877 void qemu_check_nic_model(NICInfo *nd, const char *model)
878 {
879     const char *models[2];
880 
881     models[0] = model;
882     models[1] = NULL;
883 
884     if (qemu_show_nic_models(nd->model, models))
885         exit(0);
886     if (qemu_find_nic_model(nd, models, model) < 0)
887         exit(1);
888 }
889 
890 int qemu_find_nic_model(NICInfo *nd, const char * const *models,
891                         const char *default_model)
892 {
893     int i;
894 
895     if (!nd->model)
896         nd->model = g_strdup(default_model);
897 
898     for (i = 0 ; models[i]; i++) {
899         if (strcmp(nd->model, models[i]) == 0)
900             return i;
901     }
902 
903     error_report("Unsupported NIC model: %s", nd->model);
904     return -1;
905 }
906 
907 static int net_init_nic(const Netdev *netdev, const char *name,
908                         NetClientState *peer, Error **errp)
909 {
910     int idx;
911     NICInfo *nd;
912     const NetLegacyNicOptions *nic;
913 
914     assert(netdev->type == NET_CLIENT_DRIVER_NIC);
915     nic = &netdev->u.nic;
916 
917     idx = nic_get_free_idx();
918     if (idx == -1 || nb_nics >= MAX_NICS) {
919         error_setg(errp, "too many NICs");
920         return -1;
921     }
922 
923     nd = &nd_table[idx];
924 
925     memset(nd, 0, sizeof(*nd));
926 
927     if (nic->has_netdev) {
928         nd->netdev = qemu_find_netdev(nic->netdev);
929         if (!nd->netdev) {
930             error_setg(errp, "netdev '%s' not found", nic->netdev);
931             return -1;
932         }
933     } else {
934         assert(peer);
935         nd->netdev = peer;
936     }
937     nd->name = g_strdup(name);
938     if (nic->has_model) {
939         nd->model = g_strdup(nic->model);
940     }
941     if (nic->has_addr) {
942         nd->devaddr = g_strdup(nic->addr);
943     }
944 
945     if (nic->has_macaddr &&
946         net_parse_macaddr(nd->macaddr.a, nic->macaddr) < 0) {
947         error_setg(errp, "invalid syntax for ethernet address");
948         return -1;
949     }
950     if (nic->has_macaddr &&
951         is_multicast_ether_addr(nd->macaddr.a)) {
952         error_setg(errp,
953                    "NIC cannot have multicast MAC address (odd 1st byte)");
954         return -1;
955     }
956     qemu_macaddr_default_if_unset(&nd->macaddr);
957 
958     if (nic->has_vectors) {
959         if (nic->vectors > 0x7ffffff) {
960             error_setg(errp, "invalid # of vectors: %"PRIu32, nic->vectors);
961             return -1;
962         }
963         nd->nvectors = nic->vectors;
964     } else {
965         nd->nvectors = DEV_NVECTORS_UNSPECIFIED;
966     }
967 
968     nd->used = 1;
969     nb_nics++;
970 
971     return idx;
972 }
973 
974 
975 static int (* const net_client_init_fun[NET_CLIENT_DRIVER__MAX])(
976     const Netdev *netdev,
977     const char *name,
978     NetClientState *peer, Error **errp) = {
979         [NET_CLIENT_DRIVER_NIC]       = net_init_nic,
980 #ifdef CONFIG_SLIRP
981         [NET_CLIENT_DRIVER_USER]      = net_init_slirp,
982 #endif
983         [NET_CLIENT_DRIVER_TAP]       = net_init_tap,
984         [NET_CLIENT_DRIVER_SOCKET]    = net_init_socket,
985 #ifdef CONFIG_VDE
986         [NET_CLIENT_DRIVER_VDE]       = net_init_vde,
987 #endif
988 #ifdef CONFIG_NETMAP
989         [NET_CLIENT_DRIVER_NETMAP]    = net_init_netmap,
990 #endif
991 #ifdef CONFIG_NET_BRIDGE
992         [NET_CLIENT_DRIVER_BRIDGE]    = net_init_bridge,
993 #endif
994         [NET_CLIENT_DRIVER_HUBPORT]   = net_init_hubport,
995 #ifdef CONFIG_VHOST_NET_USER
996         [NET_CLIENT_DRIVER_VHOST_USER] = net_init_vhost_user,
997 #endif
998 #ifdef CONFIG_VHOST_NET_VDPA
999         [NET_CLIENT_DRIVER_VHOST_VDPA] = net_init_vhost_vdpa,
1000 #endif
1001 #ifdef CONFIG_L2TPV3
1002         [NET_CLIENT_DRIVER_L2TPV3]    = net_init_l2tpv3,
1003 #endif
1004 };
1005 
1006 
1007 static int net_client_init1(const Netdev *netdev, bool is_netdev, Error **errp)
1008 {
1009     NetClientState *peer = NULL;
1010     NetClientState *nc;
1011 
1012     if (is_netdev) {
1013         if (netdev->type == NET_CLIENT_DRIVER_NIC ||
1014             !net_client_init_fun[netdev->type]) {
1015             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
1016                        "a netdev backend type");
1017             return -1;
1018         }
1019     } else {
1020         if (netdev->type == NET_CLIENT_DRIVER_NONE) {
1021             return 0; /* nothing to do */
1022         }
1023         if (netdev->type == NET_CLIENT_DRIVER_HUBPORT ||
1024             !net_client_init_fun[netdev->type]) {
1025             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
1026                        "a net backend type (maybe it is not compiled "
1027                        "into this binary)");
1028             return -1;
1029         }
1030 
1031         /* Do not add to a hub if it's a nic with a netdev= parameter. */
1032         if (netdev->type != NET_CLIENT_DRIVER_NIC ||
1033             !netdev->u.nic.has_netdev) {
1034             peer = net_hub_add_port(0, NULL, NULL);
1035         }
1036     }
1037 
1038     nc = qemu_find_netdev(netdev->id);
1039     if (nc) {
1040         error_setg(errp, "Duplicate ID '%s'", netdev->id);
1041         return -1;
1042     }
1043 
1044     if (net_client_init_fun[netdev->type](netdev, netdev->id, peer, errp) < 0) {
1045         /* FIXME drop when all init functions store an Error */
1046         if (errp && !*errp) {
1047             error_setg(errp, "Device '%s' could not be initialized",
1048                        NetClientDriver_str(netdev->type));
1049         }
1050         return -1;
1051     }
1052 
1053     if (is_netdev) {
1054         nc = qemu_find_netdev(netdev->id);
1055         assert(nc);
1056         nc->is_netdev = true;
1057     }
1058 
1059     return 0;
1060 }
1061 
1062 void show_netdevs(void)
1063 {
1064     int idx;
1065     const char *available_netdevs[] = {
1066         "socket",
1067         "hubport",
1068         "tap",
1069 #ifdef CONFIG_SLIRP
1070         "user",
1071 #endif
1072 #ifdef CONFIG_L2TPV3
1073         "l2tpv3",
1074 #endif
1075 #ifdef CONFIG_VDE
1076         "vde",
1077 #endif
1078 #ifdef CONFIG_NET_BRIDGE
1079         "bridge",
1080 #endif
1081 #ifdef CONFIG_NETMAP
1082         "netmap",
1083 #endif
1084 #ifdef CONFIG_POSIX
1085         "vhost-user",
1086 #endif
1087 #ifdef CONFIG_VHOST_VDPA
1088         "vhost-vdpa",
1089 #endif
1090     };
1091 
1092     qemu_printf("Available netdev backend types:\n");
1093     for (idx = 0; idx < ARRAY_SIZE(available_netdevs); idx++) {
1094         qemu_printf("%s\n", available_netdevs[idx]);
1095     }
1096 }
1097 
1098 static int net_client_init(QemuOpts *opts, bool is_netdev, Error **errp)
1099 {
1100     gchar **substrings = NULL;
1101     Netdev *object = NULL;
1102     int ret = -1;
1103     Visitor *v = opts_visitor_new(opts);
1104 
1105     /* Parse convenience option format ip6-net=fec0::0[/64] */
1106     const char *ip6_net = qemu_opt_get(opts, "ipv6-net");
1107 
1108     if (ip6_net) {
1109         char *prefix_addr;
1110         unsigned long prefix_len = 64; /* Default 64bit prefix length. */
1111 
1112         substrings = g_strsplit(ip6_net, "/", 2);
1113         if (!substrings || !substrings[0]) {
1114             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "ipv6-net",
1115                        "a valid IPv6 prefix");
1116             goto out;
1117         }
1118 
1119         prefix_addr = substrings[0];
1120 
1121         /* Handle user-specified prefix length. */
1122         if (substrings[1] &&
1123             qemu_strtoul(substrings[1], NULL, 10, &prefix_len))
1124         {
1125             error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1126                        "ipv6-prefixlen", "a number");
1127             goto out;
1128         }
1129 
1130         qemu_opt_set(opts, "ipv6-prefix", prefix_addr, &error_abort);
1131         qemu_opt_set_number(opts, "ipv6-prefixlen", prefix_len,
1132                             &error_abort);
1133         qemu_opt_unset(opts, "ipv6-net");
1134     }
1135 
1136     /* Create an ID for -net if the user did not specify one */
1137     if (!is_netdev && !qemu_opts_id(opts)) {
1138         qemu_opts_set_id(opts, id_generate(ID_NET));
1139     }
1140 
1141     if (visit_type_Netdev(v, NULL, &object, errp)) {
1142         ret = net_client_init1(object, is_netdev, errp);
1143     }
1144 
1145     qapi_free_Netdev(object);
1146 
1147 out:
1148     g_strfreev(substrings);
1149     visit_free(v);
1150     return ret;
1151 }
1152 
1153 void netdev_add(QemuOpts *opts, Error **errp)
1154 {
1155     net_client_init(opts, true, errp);
1156 }
1157 
1158 void qmp_netdev_add(Netdev *netdev, Error **errp)
1159 {
1160     if (!id_wellformed(netdev->id)) {
1161         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "id", "an identifier");
1162         return;
1163     }
1164 
1165     net_client_init1(netdev, true, errp);
1166 }
1167 
1168 void qmp_netdev_del(const char *id, Error **errp)
1169 {
1170     NetClientState *nc;
1171     QemuOpts *opts;
1172 
1173     nc = qemu_find_netdev(id);
1174     if (!nc) {
1175         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1176                   "Device '%s' not found", id);
1177         return;
1178     }
1179 
1180     if (!nc->is_netdev) {
1181         error_setg(errp, "Device '%s' is not a netdev", id);
1182         return;
1183     }
1184 
1185     qemu_del_net_client(nc);
1186 
1187     /*
1188      * Wart: we need to delete the QemuOpts associated with netdevs
1189      * created via CLI or HMP, to avoid bogus "Duplicate ID" errors in
1190      * HMP netdev_add.
1191      */
1192     opts = qemu_opts_find(qemu_find_opts("netdev"), id);
1193     if (opts) {
1194         qemu_opts_del(opts);
1195     }
1196 }
1197 
1198 static void netfilter_print_info(Monitor *mon, NetFilterState *nf)
1199 {
1200     char *str;
1201     ObjectProperty *prop;
1202     ObjectPropertyIterator iter;
1203     Visitor *v;
1204 
1205     /* generate info str */
1206     object_property_iter_init(&iter, OBJECT(nf));
1207     while ((prop = object_property_iter_next(&iter))) {
1208         if (!strcmp(prop->name, "type")) {
1209             continue;
1210         }
1211         v = string_output_visitor_new(false, &str);
1212         object_property_get(OBJECT(nf), prop->name, v, NULL);
1213         visit_complete(v, &str);
1214         visit_free(v);
1215         monitor_printf(mon, ",%s=%s", prop->name, str);
1216         g_free(str);
1217     }
1218     monitor_printf(mon, "\n");
1219 }
1220 
1221 void print_net_client(Monitor *mon, NetClientState *nc)
1222 {
1223     NetFilterState *nf;
1224 
1225     monitor_printf(mon, "%s: index=%d,type=%s,%s\n", nc->name,
1226                    nc->queue_index,
1227                    NetClientDriver_str(nc->info->type),
1228                    nc->info_str);
1229     if (!QTAILQ_EMPTY(&nc->filters)) {
1230         monitor_printf(mon, "filters:\n");
1231     }
1232     QTAILQ_FOREACH(nf, &nc->filters, next) {
1233         monitor_printf(mon, "  - %s: type=%s",
1234                        object_get_canonical_path_component(OBJECT(nf)),
1235                        object_get_typename(OBJECT(nf)));
1236         netfilter_print_info(mon, nf);
1237     }
1238 }
1239 
1240 RxFilterInfoList *qmp_query_rx_filter(bool has_name, const char *name,
1241                                       Error **errp)
1242 {
1243     NetClientState *nc;
1244     RxFilterInfoList *filter_list = NULL, **tail = &filter_list;
1245 
1246     QTAILQ_FOREACH(nc, &net_clients, next) {
1247         RxFilterInfo *info;
1248 
1249         if (has_name && strcmp(nc->name, name) != 0) {
1250             continue;
1251         }
1252 
1253         /* only query rx-filter information of NIC */
1254         if (nc->info->type != NET_CLIENT_DRIVER_NIC) {
1255             if (has_name) {
1256                 error_setg(errp, "net client(%s) isn't a NIC", name);
1257                 assert(!filter_list);
1258                 return NULL;
1259             }
1260             continue;
1261         }
1262 
1263         /* only query information on queue 0 since the info is per nic,
1264          * not per queue
1265          */
1266         if (nc->queue_index != 0)
1267             continue;
1268 
1269         if (nc->info->query_rx_filter) {
1270             info = nc->info->query_rx_filter(nc);
1271             QAPI_LIST_APPEND(tail, info);
1272         } else if (has_name) {
1273             error_setg(errp, "net client(%s) doesn't support"
1274                        " rx-filter querying", name);
1275             assert(!filter_list);
1276             return NULL;
1277         }
1278 
1279         if (has_name) {
1280             break;
1281         }
1282     }
1283 
1284     if (filter_list == NULL && has_name) {
1285         error_setg(errp, "invalid net client name: %s", name);
1286     }
1287 
1288     return filter_list;
1289 }
1290 
1291 void hmp_info_network(Monitor *mon, const QDict *qdict)
1292 {
1293     NetClientState *nc, *peer;
1294     NetClientDriver type;
1295 
1296     net_hub_info(mon);
1297 
1298     QTAILQ_FOREACH(nc, &net_clients, next) {
1299         peer = nc->peer;
1300         type = nc->info->type;
1301 
1302         /* Skip if already printed in hub info */
1303         if (net_hub_id_for_client(nc, NULL) == 0) {
1304             continue;
1305         }
1306 
1307         if (!peer || type == NET_CLIENT_DRIVER_NIC) {
1308             print_net_client(mon, nc);
1309         } /* else it's a netdev connected to a NIC, printed with the NIC */
1310         if (peer && type == NET_CLIENT_DRIVER_NIC) {
1311             monitor_printf(mon, " \\ ");
1312             print_net_client(mon, peer);
1313         }
1314     }
1315 }
1316 
1317 void colo_notify_filters_event(int event, Error **errp)
1318 {
1319     NetClientState *nc;
1320     NetFilterState *nf;
1321     NetFilterClass *nfc = NULL;
1322     Error *local_err = NULL;
1323 
1324     QTAILQ_FOREACH(nc, &net_clients, next) {
1325         QTAILQ_FOREACH(nf, &nc->filters, next) {
1326             nfc = NETFILTER_GET_CLASS(OBJECT(nf));
1327             nfc->handle_event(nf, event, &local_err);
1328             if (local_err) {
1329                 error_propagate(errp, local_err);
1330                 return;
1331             }
1332         }
1333     }
1334 }
1335 
1336 void qmp_set_link(const char *name, bool up, Error **errp)
1337 {
1338     NetClientState *ncs[MAX_QUEUE_NUM];
1339     NetClientState *nc;
1340     int queues, i;
1341 
1342     queues = qemu_find_net_clients_except(name, ncs,
1343                                           NET_CLIENT_DRIVER__MAX,
1344                                           MAX_QUEUE_NUM);
1345 
1346     if (queues == 0) {
1347         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1348                   "Device '%s' not found", name);
1349         return;
1350     }
1351     nc = ncs[0];
1352 
1353     for (i = 0; i < queues; i++) {
1354         ncs[i]->link_down = !up;
1355     }
1356 
1357     if (nc->info->link_status_changed) {
1358         nc->info->link_status_changed(nc);
1359     }
1360 
1361     if (nc->peer) {
1362         /* Change peer link only if the peer is NIC and then notify peer.
1363          * If the peer is a HUBPORT or a backend, we do not change the
1364          * link status.
1365          *
1366          * This behavior is compatible with qemu hubs where there could be
1367          * multiple clients that can still communicate with each other in
1368          * disconnected mode. For now maintain this compatibility.
1369          */
1370         if (nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
1371             for (i = 0; i < queues; i++) {
1372                 ncs[i]->peer->link_down = !up;
1373             }
1374         }
1375         if (nc->peer->info->link_status_changed) {
1376             nc->peer->info->link_status_changed(nc->peer);
1377         }
1378     }
1379 }
1380 
1381 static void net_vm_change_state_handler(void *opaque, bool running,
1382                                         RunState state)
1383 {
1384     NetClientState *nc;
1385     NetClientState *tmp;
1386 
1387     QTAILQ_FOREACH_SAFE(nc, &net_clients, next, tmp) {
1388         if (running) {
1389             /* Flush queued packets and wake up backends. */
1390             if (nc->peer && qemu_can_send_packet(nc)) {
1391                 qemu_flush_queued_packets(nc->peer);
1392             }
1393         } else {
1394             /* Complete all queued packets, to guarantee we don't modify
1395              * state later when VM is not running.
1396              */
1397             qemu_flush_or_purge_queued_packets(nc, true);
1398         }
1399     }
1400 }
1401 
1402 void net_cleanup(void)
1403 {
1404     NetClientState *nc;
1405 
1406     /*cleanup colo compare module for COLO*/
1407     colo_compare_cleanup();
1408 
1409     /* We may del multiple entries during qemu_del_net_client(),
1410      * so QTAILQ_FOREACH_SAFE() is also not safe here.
1411      */
1412     while (!QTAILQ_EMPTY(&net_clients)) {
1413         nc = QTAILQ_FIRST(&net_clients);
1414         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
1415             qemu_del_nic(qemu_get_nic(nc));
1416         } else {
1417             qemu_del_net_client(nc);
1418         }
1419     }
1420 
1421     qemu_del_vm_change_state_handler(net_change_state_entry);
1422 }
1423 
1424 void net_check_clients(void)
1425 {
1426     NetClientState *nc;
1427     int i;
1428 
1429     net_hub_check_clients();
1430 
1431     QTAILQ_FOREACH(nc, &net_clients, next) {
1432         if (!nc->peer) {
1433             warn_report("%s %s has no peer",
1434                         nc->info->type == NET_CLIENT_DRIVER_NIC
1435                         ? "nic" : "netdev",
1436                         nc->name);
1437         }
1438     }
1439 
1440     /* Check that all NICs requested via -net nic actually got created.
1441      * NICs created via -device don't need to be checked here because
1442      * they are always instantiated.
1443      */
1444     for (i = 0; i < MAX_NICS; i++) {
1445         NICInfo *nd = &nd_table[i];
1446         if (nd->used && !nd->instantiated) {
1447             warn_report("requested NIC (%s, model %s) "
1448                         "was not created (not supported by this machine?)",
1449                         nd->name ? nd->name : "anonymous",
1450                         nd->model ? nd->model : "unspecified");
1451         }
1452     }
1453 }
1454 
1455 static int net_init_client(void *dummy, QemuOpts *opts, Error **errp)
1456 {
1457     return net_client_init(opts, false, errp);
1458 }
1459 
1460 static int net_init_netdev(void *dummy, QemuOpts *opts, Error **errp)
1461 {
1462     const char *type = qemu_opt_get(opts, "type");
1463 
1464     if (type && is_help_option(type)) {
1465         show_netdevs();
1466         exit(0);
1467     }
1468     return net_client_init(opts, true, errp);
1469 }
1470 
1471 /* For the convenience "--nic" parameter */
1472 static int net_param_nic(void *dummy, QemuOpts *opts, Error **errp)
1473 {
1474     char *mac, *nd_id;
1475     int idx, ret;
1476     NICInfo *ni;
1477     const char *type;
1478 
1479     type = qemu_opt_get(opts, "type");
1480     if (type && g_str_equal(type, "none")) {
1481         return 0;    /* Nothing to do, default_net is cleared in vl.c */
1482     }
1483 
1484     idx = nic_get_free_idx();
1485     if (idx == -1 || nb_nics >= MAX_NICS) {
1486         error_setg(errp, "no more on-board/default NIC slots available");
1487         return -1;
1488     }
1489 
1490     if (!type) {
1491         qemu_opt_set(opts, "type", "user", &error_abort);
1492     }
1493 
1494     ni = &nd_table[idx];
1495     memset(ni, 0, sizeof(*ni));
1496     ni->model = qemu_opt_get_del(opts, "model");
1497 
1498     /* Create an ID if the user did not specify one */
1499     nd_id = g_strdup(qemu_opts_id(opts));
1500     if (!nd_id) {
1501         nd_id = id_generate(ID_NET);
1502         qemu_opts_set_id(opts, nd_id);
1503     }
1504 
1505     /* Handle MAC address */
1506     mac = qemu_opt_get_del(opts, "mac");
1507     if (mac) {
1508         ret = net_parse_macaddr(ni->macaddr.a, mac);
1509         g_free(mac);
1510         if (ret) {
1511             error_setg(errp, "invalid syntax for ethernet address");
1512             goto out;
1513         }
1514         if (is_multicast_ether_addr(ni->macaddr.a)) {
1515             error_setg(errp, "NIC cannot have multicast MAC address");
1516             ret = -1;
1517             goto out;
1518         }
1519     }
1520     qemu_macaddr_default_if_unset(&ni->macaddr);
1521 
1522     ret = net_client_init(opts, true, errp);
1523     if (ret == 0) {
1524         ni->netdev = qemu_find_netdev(nd_id);
1525         ni->used = true;
1526         nb_nics++;
1527     }
1528 
1529 out:
1530     g_free(nd_id);
1531     return ret;
1532 }
1533 
1534 int net_init_clients(Error **errp)
1535 {
1536     net_change_state_entry =
1537         qemu_add_vm_change_state_handler(net_vm_change_state_handler, NULL);
1538 
1539     QTAILQ_INIT(&net_clients);
1540 
1541     if (qemu_opts_foreach(qemu_find_opts("netdev"),
1542                           net_init_netdev, NULL, errp)) {
1543         return -1;
1544     }
1545 
1546     if (qemu_opts_foreach(qemu_find_opts("nic"), net_param_nic, NULL, errp)) {
1547         return -1;
1548     }
1549 
1550     if (qemu_opts_foreach(qemu_find_opts("net"), net_init_client, NULL, errp)) {
1551         return -1;
1552     }
1553 
1554     return 0;
1555 }
1556 
1557 int net_client_parse(QemuOptsList *opts_list, const char *optarg)
1558 {
1559     if (!qemu_opts_parse_noisily(opts_list, optarg, true)) {
1560         return -1;
1561     }
1562 
1563     return 0;
1564 }
1565 
1566 /* From FreeBSD */
1567 /* XXX: optimize */
1568 uint32_t net_crc32(const uint8_t *p, int len)
1569 {
1570     uint32_t crc;
1571     int carry, i, j;
1572     uint8_t b;
1573 
1574     crc = 0xffffffff;
1575     for (i = 0; i < len; i++) {
1576         b = *p++;
1577         for (j = 0; j < 8; j++) {
1578             carry = ((crc & 0x80000000L) ? 1 : 0) ^ (b & 0x01);
1579             crc <<= 1;
1580             b >>= 1;
1581             if (carry) {
1582                 crc = ((crc ^ POLYNOMIAL_BE) | carry);
1583             }
1584         }
1585     }
1586 
1587     return crc;
1588 }
1589 
1590 uint32_t net_crc32_le(const uint8_t *p, int len)
1591 {
1592     uint32_t crc;
1593     int carry, i, j;
1594     uint8_t b;
1595 
1596     crc = 0xffffffff;
1597     for (i = 0; i < len; i++) {
1598         b = *p++;
1599         for (j = 0; j < 8; j++) {
1600             carry = (crc & 0x1) ^ (b & 0x01);
1601             crc >>= 1;
1602             b >>= 1;
1603             if (carry) {
1604                 crc ^= POLYNOMIAL_LE;
1605             }
1606         }
1607     }
1608 
1609     return crc;
1610 }
1611 
1612 QemuOptsList qemu_netdev_opts = {
1613     .name = "netdev",
1614     .implied_opt_name = "type",
1615     .head = QTAILQ_HEAD_INITIALIZER(qemu_netdev_opts.head),
1616     .desc = {
1617         /*
1618          * no elements => accept any params
1619          * validation will happen later
1620          */
1621         { /* end of list */ }
1622     },
1623 };
1624 
1625 QemuOptsList qemu_nic_opts = {
1626     .name = "nic",
1627     .implied_opt_name = "type",
1628     .head = QTAILQ_HEAD_INITIALIZER(qemu_nic_opts.head),
1629     .desc = {
1630         /*
1631          * no elements => accept any params
1632          * validation will happen later
1633          */
1634         { /* end of list */ }
1635     },
1636 };
1637 
1638 QemuOptsList qemu_net_opts = {
1639     .name = "net",
1640     .implied_opt_name = "type",
1641     .head = QTAILQ_HEAD_INITIALIZER(qemu_net_opts.head),
1642     .desc = {
1643         /*
1644          * no elements => accept any params
1645          * validation will happen later
1646          */
1647         { /* end of list */ }
1648     },
1649 };
1650 
1651 void net_socket_rs_init(SocketReadState *rs,
1652                         SocketReadStateFinalize *finalize,
1653                         bool vnet_hdr)
1654 {
1655     rs->state = 0;
1656     rs->vnet_hdr = vnet_hdr;
1657     rs->index = 0;
1658     rs->packet_len = 0;
1659     rs->vnet_hdr_len = 0;
1660     memset(rs->buf, 0, sizeof(rs->buf));
1661     rs->finalize = finalize;
1662 }
1663 
1664 /*
1665  * Returns
1666  * 0: success
1667  * -1: error occurs
1668  */
1669 int net_fill_rstate(SocketReadState *rs, const uint8_t *buf, int size)
1670 {
1671     unsigned int l;
1672 
1673     while (size > 0) {
1674         /* Reassemble a packet from the network.
1675          * 0 = getting length.
1676          * 1 = getting vnet header length.
1677          * 2 = getting data.
1678          */
1679         switch (rs->state) {
1680         case 0:
1681             l = 4 - rs->index;
1682             if (l > size) {
1683                 l = size;
1684             }
1685             memcpy(rs->buf + rs->index, buf, l);
1686             buf += l;
1687             size -= l;
1688             rs->index += l;
1689             if (rs->index == 4) {
1690                 /* got length */
1691                 rs->packet_len = ntohl(*(uint32_t *)rs->buf);
1692                 rs->index = 0;
1693                 if (rs->vnet_hdr) {
1694                     rs->state = 1;
1695                 } else {
1696                     rs->state = 2;
1697                     rs->vnet_hdr_len = 0;
1698                 }
1699             }
1700             break;
1701         case 1:
1702             l = 4 - rs->index;
1703             if (l > size) {
1704                 l = size;
1705             }
1706             memcpy(rs->buf + rs->index, buf, l);
1707             buf += l;
1708             size -= l;
1709             rs->index += l;
1710             if (rs->index == 4) {
1711                 /* got vnet header length */
1712                 rs->vnet_hdr_len = ntohl(*(uint32_t *)rs->buf);
1713                 rs->index = 0;
1714                 rs->state = 2;
1715             }
1716             break;
1717         case 2:
1718             l = rs->packet_len - rs->index;
1719             if (l > size) {
1720                 l = size;
1721             }
1722             if (rs->index + l <= sizeof(rs->buf)) {
1723                 memcpy(rs->buf + rs->index, buf, l);
1724             } else {
1725                 fprintf(stderr, "serious error: oversized packet received,"
1726                     "connection terminated.\n");
1727                 rs->index = rs->state = 0;
1728                 return -1;
1729             }
1730 
1731             rs->index += l;
1732             buf += l;
1733             size -= l;
1734             if (rs->index >= rs->packet_len) {
1735                 rs->index = 0;
1736                 rs->state = 0;
1737                 assert(rs->finalize);
1738                 rs->finalize(rs);
1739             }
1740             break;
1741         }
1742     }
1743 
1744     assert(size == 0);
1745     return 0;
1746 }
1747