xref: /qemu/net/net.c (revision 15991968a072bca0f73eaa7929273afd80f70979)
1 /*
2  * QEMU System Emulator
3  *
4  * Copyright (c) 2003-2008 Fabrice Bellard
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 #include "qemu/osdep.h"
26 
27 #include "net/net.h"
28 #include "clients.h"
29 #include "hub.h"
30 #include "hw/qdev-properties.h"
31 #include "net/slirp.h"
32 #include "net/eth.h"
33 #include "util.h"
34 
35 #include "monitor/monitor.h"
36 #include "qemu/help_option.h"
37 #include "qapi/qapi-commands-net.h"
38 #include "qapi/qapi-visit-net.h"
39 #include "qapi/qmp/qdict.h"
40 #include "qapi/qmp/qerror.h"
41 #include "qemu/error-report.h"
42 #include "qemu/sockets.h"
43 #include "qemu/cutils.h"
44 #include "qemu/config-file.h"
45 #include "qemu/ctype.h"
46 #include "qemu/id.h"
47 #include "qemu/iov.h"
48 #include "qemu/qemu-print.h"
49 #include "qemu/main-loop.h"
50 #include "qemu/option.h"
51 #include "qapi/error.h"
52 #include "qapi/opts-visitor.h"
53 #include "sysemu/sysemu.h"
54 #include "sysemu/runstate.h"
55 #include "sysemu/sysemu.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_send_packet(NetClientState *sender)
532 {
533     int vm_running = runstate_is_running();
534 
535     if (!vm_running) {
536         return 0;
537     }
538 
539     if (!sender->peer) {
540         return 1;
541     }
542 
543     if (sender->peer->receive_disabled) {
544         return 0;
545     } else if (sender->peer->info->can_receive &&
546                !sender->peer->info->can_receive(sender->peer)) {
547         return 0;
548     }
549     return 1;
550 }
551 
552 static ssize_t filter_receive_iov(NetClientState *nc,
553                                   NetFilterDirection direction,
554                                   NetClientState *sender,
555                                   unsigned flags,
556                                   const struct iovec *iov,
557                                   int iovcnt,
558                                   NetPacketSent *sent_cb)
559 {
560     ssize_t ret = 0;
561     NetFilterState *nf = NULL;
562 
563     if (direction == NET_FILTER_DIRECTION_TX) {
564         QTAILQ_FOREACH(nf, &nc->filters, next) {
565             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
566                                          iovcnt, sent_cb);
567             if (ret) {
568                 return ret;
569             }
570         }
571     } else {
572         QTAILQ_FOREACH_REVERSE(nf, &nc->filters, next) {
573             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
574                                          iovcnt, sent_cb);
575             if (ret) {
576                 return ret;
577             }
578         }
579     }
580 
581     return ret;
582 }
583 
584 static ssize_t filter_receive(NetClientState *nc,
585                               NetFilterDirection direction,
586                               NetClientState *sender,
587                               unsigned flags,
588                               const uint8_t *data,
589                               size_t size,
590                               NetPacketSent *sent_cb)
591 {
592     struct iovec iov = {
593         .iov_base = (void *)data,
594         .iov_len = size
595     };
596 
597     return filter_receive_iov(nc, direction, sender, flags, &iov, 1, sent_cb);
598 }
599 
600 void qemu_purge_queued_packets(NetClientState *nc)
601 {
602     if (!nc->peer) {
603         return;
604     }
605 
606     qemu_net_queue_purge(nc->peer->incoming_queue, nc);
607 }
608 
609 void qemu_flush_or_purge_queued_packets(NetClientState *nc, bool purge)
610 {
611     nc->receive_disabled = 0;
612 
613     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_HUBPORT) {
614         if (net_hub_flush(nc->peer)) {
615             qemu_notify_event();
616         }
617     }
618     if (qemu_net_queue_flush(nc->incoming_queue)) {
619         /* We emptied the queue successfully, signal to the IO thread to repoll
620          * the file descriptor (for tap, for example).
621          */
622         qemu_notify_event();
623     } else if (purge) {
624         /* Unable to empty the queue, purge remaining packets */
625         qemu_net_queue_purge(nc->incoming_queue, nc->peer);
626     }
627 }
628 
629 void qemu_flush_queued_packets(NetClientState *nc)
630 {
631     qemu_flush_or_purge_queued_packets(nc, false);
632 }
633 
634 static ssize_t qemu_send_packet_async_with_flags(NetClientState *sender,
635                                                  unsigned flags,
636                                                  const uint8_t *buf, int size,
637                                                  NetPacketSent *sent_cb)
638 {
639     NetQueue *queue;
640     int ret;
641 
642 #ifdef DEBUG_NET
643     printf("qemu_send_packet_async:\n");
644     qemu_hexdump(stdout, "net", buf, size);
645 #endif
646 
647     if (sender->link_down || !sender->peer) {
648         return size;
649     }
650 
651     /* Let filters handle the packet first */
652     ret = filter_receive(sender, NET_FILTER_DIRECTION_TX,
653                          sender, flags, buf, size, sent_cb);
654     if (ret) {
655         return ret;
656     }
657 
658     ret = filter_receive(sender->peer, NET_FILTER_DIRECTION_RX,
659                          sender, flags, buf, size, sent_cb);
660     if (ret) {
661         return ret;
662     }
663 
664     queue = sender->peer->incoming_queue;
665 
666     return qemu_net_queue_send(queue, sender, flags, buf, size, sent_cb);
667 }
668 
669 ssize_t qemu_send_packet_async(NetClientState *sender,
670                                const uint8_t *buf, int size,
671                                NetPacketSent *sent_cb)
672 {
673     return qemu_send_packet_async_with_flags(sender, QEMU_NET_PACKET_FLAG_NONE,
674                                              buf, size, sent_cb);
675 }
676 
677 ssize_t qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size)
678 {
679     return qemu_send_packet_async(nc, buf, size, NULL);
680 }
681 
682 ssize_t qemu_send_packet_raw(NetClientState *nc, const uint8_t *buf, int size)
683 {
684     return qemu_send_packet_async_with_flags(nc, QEMU_NET_PACKET_FLAG_RAW,
685                                              buf, size, NULL);
686 }
687 
688 static ssize_t nc_sendv_compat(NetClientState *nc, const struct iovec *iov,
689                                int iovcnt, unsigned flags)
690 {
691     uint8_t *buf = NULL;
692     uint8_t *buffer;
693     size_t offset;
694     ssize_t ret;
695 
696     if (iovcnt == 1) {
697         buffer = iov[0].iov_base;
698         offset = iov[0].iov_len;
699     } else {
700         offset = iov_size(iov, iovcnt);
701         if (offset > NET_BUFSIZE) {
702             return -1;
703         }
704         buf = g_malloc(offset);
705         buffer = buf;
706         offset = iov_to_buf(iov, iovcnt, 0, buf, offset);
707     }
708 
709     if (flags & QEMU_NET_PACKET_FLAG_RAW && nc->info->receive_raw) {
710         ret = nc->info->receive_raw(nc, buffer, offset);
711     } else {
712         ret = nc->info->receive(nc, buffer, offset);
713     }
714 
715     g_free(buf);
716     return ret;
717 }
718 
719 static ssize_t qemu_deliver_packet_iov(NetClientState *sender,
720                                        unsigned flags,
721                                        const struct iovec *iov,
722                                        int iovcnt,
723                                        void *opaque)
724 {
725     NetClientState *nc = opaque;
726     int ret;
727 
728 
729     if (nc->link_down) {
730         return iov_size(iov, iovcnt);
731     }
732 
733     if (nc->receive_disabled) {
734         return 0;
735     }
736 
737     if (nc->info->receive_iov && !(flags & QEMU_NET_PACKET_FLAG_RAW)) {
738         ret = nc->info->receive_iov(nc, iov, iovcnt);
739     } else {
740         ret = nc_sendv_compat(nc, iov, iovcnt, flags);
741     }
742 
743     if (ret == 0) {
744         nc->receive_disabled = 1;
745     }
746 
747     return ret;
748 }
749 
750 ssize_t qemu_sendv_packet_async(NetClientState *sender,
751                                 const struct iovec *iov, int iovcnt,
752                                 NetPacketSent *sent_cb)
753 {
754     NetQueue *queue;
755     size_t size = iov_size(iov, iovcnt);
756     int ret;
757 
758     if (size > NET_BUFSIZE) {
759         return size;
760     }
761 
762     if (sender->link_down || !sender->peer) {
763         return size;
764     }
765 
766     /* Let filters handle the packet first */
767     ret = filter_receive_iov(sender, NET_FILTER_DIRECTION_TX, sender,
768                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
769     if (ret) {
770         return ret;
771     }
772 
773     ret = filter_receive_iov(sender->peer, NET_FILTER_DIRECTION_RX, sender,
774                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
775     if (ret) {
776         return ret;
777     }
778 
779     queue = sender->peer->incoming_queue;
780 
781     return qemu_net_queue_send_iov(queue, sender,
782                                    QEMU_NET_PACKET_FLAG_NONE,
783                                    iov, iovcnt, sent_cb);
784 }
785 
786 ssize_t
787 qemu_sendv_packet(NetClientState *nc, const struct iovec *iov, int iovcnt)
788 {
789     return qemu_sendv_packet_async(nc, iov, iovcnt, NULL);
790 }
791 
792 NetClientState *qemu_find_netdev(const char *id)
793 {
794     NetClientState *nc;
795 
796     QTAILQ_FOREACH(nc, &net_clients, next) {
797         if (nc->info->type == NET_CLIENT_DRIVER_NIC)
798             continue;
799         if (!strcmp(nc->name, id)) {
800             return nc;
801         }
802     }
803 
804     return NULL;
805 }
806 
807 int qemu_find_net_clients_except(const char *id, NetClientState **ncs,
808                                  NetClientDriver type, int max)
809 {
810     NetClientState *nc;
811     int ret = 0;
812 
813     QTAILQ_FOREACH(nc, &net_clients, next) {
814         if (nc->info->type == type) {
815             continue;
816         }
817         if (!id || !strcmp(nc->name, id)) {
818             if (ret < max) {
819                 ncs[ret] = nc;
820             }
821             ret++;
822         }
823     }
824 
825     return ret;
826 }
827 
828 static int nic_get_free_idx(void)
829 {
830     int index;
831 
832     for (index = 0; index < MAX_NICS; index++)
833         if (!nd_table[index].used)
834             return index;
835     return -1;
836 }
837 
838 int qemu_show_nic_models(const char *arg, const char *const *models)
839 {
840     int i;
841 
842     if (!arg || !is_help_option(arg)) {
843         return 0;
844     }
845 
846     printf("Supported NIC models:\n");
847     for (i = 0 ; models[i]; i++) {
848         printf("%s\n", models[i]);
849     }
850     return 1;
851 }
852 
853 void qemu_check_nic_model(NICInfo *nd, const char *model)
854 {
855     const char *models[2];
856 
857     models[0] = model;
858     models[1] = NULL;
859 
860     if (qemu_show_nic_models(nd->model, models))
861         exit(0);
862     if (qemu_find_nic_model(nd, models, model) < 0)
863         exit(1);
864 }
865 
866 int qemu_find_nic_model(NICInfo *nd, const char * const *models,
867                         const char *default_model)
868 {
869     int i;
870 
871     if (!nd->model)
872         nd->model = g_strdup(default_model);
873 
874     for (i = 0 ; models[i]; i++) {
875         if (strcmp(nd->model, models[i]) == 0)
876             return i;
877     }
878 
879     error_report("Unsupported NIC model: %s", nd->model);
880     return -1;
881 }
882 
883 static int net_init_nic(const Netdev *netdev, const char *name,
884                         NetClientState *peer, Error **errp)
885 {
886     int idx;
887     NICInfo *nd;
888     const NetLegacyNicOptions *nic;
889 
890     assert(netdev->type == NET_CLIENT_DRIVER_NIC);
891     nic = &netdev->u.nic;
892 
893     idx = nic_get_free_idx();
894     if (idx == -1 || nb_nics >= MAX_NICS) {
895         error_setg(errp, "too many NICs");
896         return -1;
897     }
898 
899     nd = &nd_table[idx];
900 
901     memset(nd, 0, sizeof(*nd));
902 
903     if (nic->has_netdev) {
904         nd->netdev = qemu_find_netdev(nic->netdev);
905         if (!nd->netdev) {
906             error_setg(errp, "netdev '%s' not found", nic->netdev);
907             return -1;
908         }
909     } else {
910         assert(peer);
911         nd->netdev = peer;
912     }
913     nd->name = g_strdup(name);
914     if (nic->has_model) {
915         nd->model = g_strdup(nic->model);
916     }
917     if (nic->has_addr) {
918         nd->devaddr = g_strdup(nic->addr);
919     }
920 
921     if (nic->has_macaddr &&
922         net_parse_macaddr(nd->macaddr.a, nic->macaddr) < 0) {
923         error_setg(errp, "invalid syntax for ethernet address");
924         return -1;
925     }
926     if (nic->has_macaddr &&
927         is_multicast_ether_addr(nd->macaddr.a)) {
928         error_setg(errp,
929                    "NIC cannot have multicast MAC address (odd 1st byte)");
930         return -1;
931     }
932     qemu_macaddr_default_if_unset(&nd->macaddr);
933 
934     if (nic->has_vectors) {
935         if (nic->vectors > 0x7ffffff) {
936             error_setg(errp, "invalid # of vectors: %"PRIu32, nic->vectors);
937             return -1;
938         }
939         nd->nvectors = nic->vectors;
940     } else {
941         nd->nvectors = DEV_NVECTORS_UNSPECIFIED;
942     }
943 
944     nd->used = 1;
945     nb_nics++;
946 
947     return idx;
948 }
949 
950 
951 static int (* const net_client_init_fun[NET_CLIENT_DRIVER__MAX])(
952     const Netdev *netdev,
953     const char *name,
954     NetClientState *peer, Error **errp) = {
955         [NET_CLIENT_DRIVER_NIC]       = net_init_nic,
956 #ifdef CONFIG_SLIRP
957         [NET_CLIENT_DRIVER_USER]      = net_init_slirp,
958 #endif
959         [NET_CLIENT_DRIVER_TAP]       = net_init_tap,
960         [NET_CLIENT_DRIVER_SOCKET]    = net_init_socket,
961 #ifdef CONFIG_VDE
962         [NET_CLIENT_DRIVER_VDE]       = net_init_vde,
963 #endif
964 #ifdef CONFIG_NETMAP
965         [NET_CLIENT_DRIVER_NETMAP]    = net_init_netmap,
966 #endif
967 #ifdef CONFIG_NET_BRIDGE
968         [NET_CLIENT_DRIVER_BRIDGE]    = net_init_bridge,
969 #endif
970         [NET_CLIENT_DRIVER_HUBPORT]   = net_init_hubport,
971 #ifdef CONFIG_VHOST_NET_USER
972         [NET_CLIENT_DRIVER_VHOST_USER] = net_init_vhost_user,
973 #endif
974 #ifdef CONFIG_VHOST_NET_VDPA
975         [NET_CLIENT_DRIVER_VHOST_VDPA] = net_init_vhost_vdpa,
976 #endif
977 #ifdef CONFIG_L2TPV3
978         [NET_CLIENT_DRIVER_L2TPV3]    = net_init_l2tpv3,
979 #endif
980 };
981 
982 
983 static int net_client_init1(const Netdev *netdev, bool is_netdev, Error **errp)
984 {
985     NetClientState *peer = NULL;
986     NetClientState *nc;
987 
988     if (is_netdev) {
989         if (netdev->type == NET_CLIENT_DRIVER_NIC ||
990             !net_client_init_fun[netdev->type]) {
991             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
992                        "a netdev backend type");
993             return -1;
994         }
995     } else {
996         if (netdev->type == NET_CLIENT_DRIVER_NONE) {
997             return 0; /* nothing to do */
998         }
999         if (netdev->type == NET_CLIENT_DRIVER_HUBPORT ||
1000             !net_client_init_fun[netdev->type]) {
1001             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
1002                        "a net backend type (maybe it is not compiled "
1003                        "into this binary)");
1004             return -1;
1005         }
1006 
1007         /* Do not add to a hub if it's a nic with a netdev= parameter. */
1008         if (netdev->type != NET_CLIENT_DRIVER_NIC ||
1009             !netdev->u.nic.has_netdev) {
1010             peer = net_hub_add_port(0, NULL, NULL);
1011         }
1012     }
1013 
1014     nc = qemu_find_netdev(netdev->id);
1015     if (nc) {
1016         error_setg(errp, "Duplicate ID '%s'", netdev->id);
1017         return -1;
1018     }
1019 
1020     if (net_client_init_fun[netdev->type](netdev, netdev->id, peer, errp) < 0) {
1021         /* FIXME drop when all init functions store an Error */
1022         if (errp && !*errp) {
1023             error_setg(errp, "Device '%s' could not be initialized",
1024                        NetClientDriver_str(netdev->type));
1025         }
1026         return -1;
1027     }
1028 
1029     if (is_netdev) {
1030         nc = qemu_find_netdev(netdev->id);
1031         assert(nc);
1032         nc->is_netdev = true;
1033     }
1034 
1035     return 0;
1036 }
1037 
1038 void show_netdevs(void)
1039 {
1040     int idx;
1041     const char *available_netdevs[] = {
1042         "socket",
1043         "hubport",
1044         "tap",
1045 #ifdef CONFIG_SLIRP
1046         "user",
1047 #endif
1048 #ifdef CONFIG_L2TPV3
1049         "l2tpv3",
1050 #endif
1051 #ifdef CONFIG_VDE
1052         "vde",
1053 #endif
1054 #ifdef CONFIG_NET_BRIDGE
1055         "bridge",
1056 #endif
1057 #ifdef CONFIG_NETMAP
1058         "netmap",
1059 #endif
1060 #ifdef CONFIG_POSIX
1061         "vhost-user",
1062 #endif
1063 #ifdef CONFIG_VHOST_VDPA
1064         "vhost-vdpa",
1065 #endif
1066     };
1067 
1068     qemu_printf("Available netdev backend types:\n");
1069     for (idx = 0; idx < ARRAY_SIZE(available_netdevs); idx++) {
1070         qemu_printf("%s\n", available_netdevs[idx]);
1071     }
1072 }
1073 
1074 static int net_client_init(QemuOpts *opts, bool is_netdev, Error **errp)
1075 {
1076     gchar **substrings = NULL;
1077     Netdev *object = NULL;
1078     int ret = -1;
1079     Visitor *v = opts_visitor_new(opts);
1080 
1081     /* Parse convenience option format ip6-net=fec0::0[/64] */
1082     const char *ip6_net = qemu_opt_get(opts, "ipv6-net");
1083 
1084     if (ip6_net) {
1085         char *prefix_addr;
1086         unsigned long prefix_len = 64; /* Default 64bit prefix length. */
1087 
1088         substrings = g_strsplit(ip6_net, "/", 2);
1089         if (!substrings || !substrings[0]) {
1090             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "ipv6-net",
1091                        "a valid IPv6 prefix");
1092             goto out;
1093         }
1094 
1095         prefix_addr = substrings[0];
1096 
1097         /* Handle user-specified prefix length. */
1098         if (substrings[1] &&
1099             qemu_strtoul(substrings[1], NULL, 10, &prefix_len))
1100         {
1101             error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1102                        "ipv6-prefixlen", "a number");
1103             goto out;
1104         }
1105 
1106         qemu_opt_set(opts, "ipv6-prefix", prefix_addr, &error_abort);
1107         qemu_opt_set_number(opts, "ipv6-prefixlen", prefix_len,
1108                             &error_abort);
1109         qemu_opt_unset(opts, "ipv6-net");
1110     }
1111 
1112     /* Create an ID for -net if the user did not specify one */
1113     if (!is_netdev && !qemu_opts_id(opts)) {
1114         qemu_opts_set_id(opts, id_generate(ID_NET));
1115     }
1116 
1117     if (visit_type_Netdev(v, NULL, &object, errp)) {
1118         ret = net_client_init1(object, is_netdev, errp);
1119     }
1120 
1121     qapi_free_Netdev(object);
1122 
1123 out:
1124     g_strfreev(substrings);
1125     visit_free(v);
1126     return ret;
1127 }
1128 
1129 void netdev_add(QemuOpts *opts, Error **errp)
1130 {
1131     net_client_init(opts, true, errp);
1132 }
1133 
1134 void qmp_netdev_add(Netdev *netdev, Error **errp)
1135 {
1136     net_client_init1(netdev, true, errp);
1137 }
1138 
1139 void qmp_netdev_del(const char *id, Error **errp)
1140 {
1141     NetClientState *nc;
1142     QemuOpts *opts;
1143 
1144     nc = qemu_find_netdev(id);
1145     if (!nc) {
1146         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1147                   "Device '%s' not found", id);
1148         return;
1149     }
1150 
1151     if (!nc->is_netdev) {
1152         error_setg(errp, "Device '%s' is not a netdev", id);
1153         return;
1154     }
1155 
1156     qemu_del_net_client(nc);
1157 
1158     /*
1159      * Wart: we need to delete the QemuOpts associated with netdevs
1160      * created via CLI or HMP, to avoid bogus "Duplicate ID" errors in
1161      * HMP netdev_add.
1162      */
1163     opts = qemu_opts_find(qemu_find_opts("netdev"), id);
1164     if (opts) {
1165         qemu_opts_del(opts);
1166     }
1167 }
1168 
1169 static void netfilter_print_info(Monitor *mon, NetFilterState *nf)
1170 {
1171     char *str;
1172     ObjectProperty *prop;
1173     ObjectPropertyIterator iter;
1174     Visitor *v;
1175 
1176     /* generate info str */
1177     object_property_iter_init(&iter, OBJECT(nf));
1178     while ((prop = object_property_iter_next(&iter))) {
1179         if (!strcmp(prop->name, "type")) {
1180             continue;
1181         }
1182         v = string_output_visitor_new(false, &str);
1183         object_property_get(OBJECT(nf), prop->name, v, NULL);
1184         visit_complete(v, &str);
1185         visit_free(v);
1186         monitor_printf(mon, ",%s=%s", prop->name, str);
1187         g_free(str);
1188     }
1189     monitor_printf(mon, "\n");
1190 }
1191 
1192 void print_net_client(Monitor *mon, NetClientState *nc)
1193 {
1194     NetFilterState *nf;
1195 
1196     monitor_printf(mon, "%s: index=%d,type=%s,%s\n", nc->name,
1197                    nc->queue_index,
1198                    NetClientDriver_str(nc->info->type),
1199                    nc->info_str);
1200     if (!QTAILQ_EMPTY(&nc->filters)) {
1201         monitor_printf(mon, "filters:\n");
1202     }
1203     QTAILQ_FOREACH(nf, &nc->filters, next) {
1204         monitor_printf(mon, "  - %s: type=%s",
1205                        object_get_canonical_path_component(OBJECT(nf)),
1206                        object_get_typename(OBJECT(nf)));
1207         netfilter_print_info(mon, nf);
1208     }
1209 }
1210 
1211 RxFilterInfoList *qmp_query_rx_filter(bool has_name, const char *name,
1212                                       Error **errp)
1213 {
1214     NetClientState *nc;
1215     RxFilterInfoList *filter_list = NULL, **tail = &filter_list;
1216 
1217     QTAILQ_FOREACH(nc, &net_clients, next) {
1218         RxFilterInfo *info;
1219 
1220         if (has_name && strcmp(nc->name, name) != 0) {
1221             continue;
1222         }
1223 
1224         /* only query rx-filter information of NIC */
1225         if (nc->info->type != NET_CLIENT_DRIVER_NIC) {
1226             if (has_name) {
1227                 error_setg(errp, "net client(%s) isn't a NIC", name);
1228                 assert(!filter_list);
1229                 return NULL;
1230             }
1231             continue;
1232         }
1233 
1234         /* only query information on queue 0 since the info is per nic,
1235          * not per queue
1236          */
1237         if (nc->queue_index != 0)
1238             continue;
1239 
1240         if (nc->info->query_rx_filter) {
1241             info = nc->info->query_rx_filter(nc);
1242             QAPI_LIST_APPEND(tail, info);
1243         } else if (has_name) {
1244             error_setg(errp, "net client(%s) doesn't support"
1245                        " rx-filter querying", name);
1246             assert(!filter_list);
1247             return NULL;
1248         }
1249 
1250         if (has_name) {
1251             break;
1252         }
1253     }
1254 
1255     if (filter_list == NULL && has_name) {
1256         error_setg(errp, "invalid net client name: %s", name);
1257     }
1258 
1259     return filter_list;
1260 }
1261 
1262 void hmp_info_network(Monitor *mon, const QDict *qdict)
1263 {
1264     NetClientState *nc, *peer;
1265     NetClientDriver type;
1266 
1267     net_hub_info(mon);
1268 
1269     QTAILQ_FOREACH(nc, &net_clients, next) {
1270         peer = nc->peer;
1271         type = nc->info->type;
1272 
1273         /* Skip if already printed in hub info */
1274         if (net_hub_id_for_client(nc, NULL) == 0) {
1275             continue;
1276         }
1277 
1278         if (!peer || type == NET_CLIENT_DRIVER_NIC) {
1279             print_net_client(mon, nc);
1280         } /* else it's a netdev connected to a NIC, printed with the NIC */
1281         if (peer && type == NET_CLIENT_DRIVER_NIC) {
1282             monitor_printf(mon, " \\ ");
1283             print_net_client(mon, peer);
1284         }
1285     }
1286 }
1287 
1288 void colo_notify_filters_event(int event, Error **errp)
1289 {
1290     NetClientState *nc;
1291     NetFilterState *nf;
1292     NetFilterClass *nfc = NULL;
1293     Error *local_err = NULL;
1294 
1295     QTAILQ_FOREACH(nc, &net_clients, next) {
1296         QTAILQ_FOREACH(nf, &nc->filters, next) {
1297             nfc = NETFILTER_GET_CLASS(OBJECT(nf));
1298             nfc->handle_event(nf, event, &local_err);
1299             if (local_err) {
1300                 error_propagate(errp, local_err);
1301                 return;
1302             }
1303         }
1304     }
1305 }
1306 
1307 void qmp_set_link(const char *name, bool up, Error **errp)
1308 {
1309     NetClientState *ncs[MAX_QUEUE_NUM];
1310     NetClientState *nc;
1311     int queues, i;
1312 
1313     queues = qemu_find_net_clients_except(name, ncs,
1314                                           NET_CLIENT_DRIVER__MAX,
1315                                           MAX_QUEUE_NUM);
1316 
1317     if (queues == 0) {
1318         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1319                   "Device '%s' not found", name);
1320         return;
1321     }
1322     nc = ncs[0];
1323 
1324     for (i = 0; i < queues; i++) {
1325         ncs[i]->link_down = !up;
1326     }
1327 
1328     if (nc->info->link_status_changed) {
1329         nc->info->link_status_changed(nc);
1330     }
1331 
1332     if (nc->peer) {
1333         /* Change peer link only if the peer is NIC and then notify peer.
1334          * If the peer is a HUBPORT or a backend, we do not change the
1335          * link status.
1336          *
1337          * This behavior is compatible with qemu hubs where there could be
1338          * multiple clients that can still communicate with each other in
1339          * disconnected mode. For now maintain this compatibility.
1340          */
1341         if (nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
1342             for (i = 0; i < queues; i++) {
1343                 ncs[i]->peer->link_down = !up;
1344             }
1345         }
1346         if (nc->peer->info->link_status_changed) {
1347             nc->peer->info->link_status_changed(nc->peer);
1348         }
1349     }
1350 }
1351 
1352 static void net_vm_change_state_handler(void *opaque, bool running,
1353                                         RunState state)
1354 {
1355     NetClientState *nc;
1356     NetClientState *tmp;
1357 
1358     QTAILQ_FOREACH_SAFE(nc, &net_clients, next, tmp) {
1359         if (running) {
1360             /* Flush queued packets and wake up backends. */
1361             if (nc->peer && qemu_can_send_packet(nc)) {
1362                 qemu_flush_queued_packets(nc->peer);
1363             }
1364         } else {
1365             /* Complete all queued packets, to guarantee we don't modify
1366              * state later when VM is not running.
1367              */
1368             qemu_flush_or_purge_queued_packets(nc, true);
1369         }
1370     }
1371 }
1372 
1373 void net_cleanup(void)
1374 {
1375     NetClientState *nc;
1376 
1377     /* We may del multiple entries during qemu_del_net_client(),
1378      * so QTAILQ_FOREACH_SAFE() is also not safe here.
1379      */
1380     while (!QTAILQ_EMPTY(&net_clients)) {
1381         nc = QTAILQ_FIRST(&net_clients);
1382         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
1383             qemu_del_nic(qemu_get_nic(nc));
1384         } else {
1385             qemu_del_net_client(nc);
1386         }
1387     }
1388 
1389     qemu_del_vm_change_state_handler(net_change_state_entry);
1390 }
1391 
1392 void net_check_clients(void)
1393 {
1394     NetClientState *nc;
1395     int i;
1396 
1397     net_hub_check_clients();
1398 
1399     QTAILQ_FOREACH(nc, &net_clients, next) {
1400         if (!nc->peer) {
1401             warn_report("%s %s has no peer",
1402                         nc->info->type == NET_CLIENT_DRIVER_NIC
1403                         ? "nic" : "netdev",
1404                         nc->name);
1405         }
1406     }
1407 
1408     /* Check that all NICs requested via -net nic actually got created.
1409      * NICs created via -device don't need to be checked here because
1410      * they are always instantiated.
1411      */
1412     for (i = 0; i < MAX_NICS; i++) {
1413         NICInfo *nd = &nd_table[i];
1414         if (nd->used && !nd->instantiated) {
1415             warn_report("requested NIC (%s, model %s) "
1416                         "was not created (not supported by this machine?)",
1417                         nd->name ? nd->name : "anonymous",
1418                         nd->model ? nd->model : "unspecified");
1419         }
1420     }
1421 }
1422 
1423 static int net_init_client(void *dummy, QemuOpts *opts, Error **errp)
1424 {
1425     return net_client_init(opts, false, errp);
1426 }
1427 
1428 static int net_init_netdev(void *dummy, QemuOpts *opts, Error **errp)
1429 {
1430     const char *type = qemu_opt_get(opts, "type");
1431 
1432     if (type && is_help_option(type)) {
1433         show_netdevs();
1434         exit(0);
1435     }
1436     return net_client_init(opts, true, errp);
1437 }
1438 
1439 /* For the convenience "--nic" parameter */
1440 static int net_param_nic(void *dummy, QemuOpts *opts, Error **errp)
1441 {
1442     char *mac, *nd_id;
1443     int idx, ret;
1444     NICInfo *ni;
1445     const char *type;
1446 
1447     type = qemu_opt_get(opts, "type");
1448     if (type && g_str_equal(type, "none")) {
1449         return 0;    /* Nothing to do, default_net is cleared in vl.c */
1450     }
1451 
1452     idx = nic_get_free_idx();
1453     if (idx == -1 || nb_nics >= MAX_NICS) {
1454         error_setg(errp, "no more on-board/default NIC slots available");
1455         return -1;
1456     }
1457 
1458     if (!type) {
1459         qemu_opt_set(opts, "type", "user", &error_abort);
1460     }
1461 
1462     ni = &nd_table[idx];
1463     memset(ni, 0, sizeof(*ni));
1464     ni->model = qemu_opt_get_del(opts, "model");
1465 
1466     /* Create an ID if the user did not specify one */
1467     nd_id = g_strdup(qemu_opts_id(opts));
1468     if (!nd_id) {
1469         nd_id = id_generate(ID_NET);
1470         qemu_opts_set_id(opts, nd_id);
1471     }
1472 
1473     /* Handle MAC address */
1474     mac = qemu_opt_get_del(opts, "mac");
1475     if (mac) {
1476         ret = net_parse_macaddr(ni->macaddr.a, mac);
1477         g_free(mac);
1478         if (ret) {
1479             error_setg(errp, "invalid syntax for ethernet address");
1480             goto out;
1481         }
1482         if (is_multicast_ether_addr(ni->macaddr.a)) {
1483             error_setg(errp, "NIC cannot have multicast MAC address");
1484             ret = -1;
1485             goto out;
1486         }
1487     }
1488     qemu_macaddr_default_if_unset(&ni->macaddr);
1489 
1490     ret = net_client_init(opts, true, errp);
1491     if (ret == 0) {
1492         ni->netdev = qemu_find_netdev(nd_id);
1493         ni->used = true;
1494         nb_nics++;
1495     }
1496 
1497 out:
1498     g_free(nd_id);
1499     return ret;
1500 }
1501 
1502 int net_init_clients(Error **errp)
1503 {
1504     net_change_state_entry =
1505         qemu_add_vm_change_state_handler(net_vm_change_state_handler, NULL);
1506 
1507     QTAILQ_INIT(&net_clients);
1508 
1509     if (qemu_opts_foreach(qemu_find_opts("netdev"),
1510                           net_init_netdev, NULL, errp)) {
1511         return -1;
1512     }
1513 
1514     if (qemu_opts_foreach(qemu_find_opts("nic"), net_param_nic, NULL, errp)) {
1515         return -1;
1516     }
1517 
1518     if (qemu_opts_foreach(qemu_find_opts("net"), net_init_client, NULL, errp)) {
1519         return -1;
1520     }
1521 
1522     return 0;
1523 }
1524 
1525 int net_client_parse(QemuOptsList *opts_list, const char *optarg)
1526 {
1527     if (!qemu_opts_parse_noisily(opts_list, optarg, true)) {
1528         return -1;
1529     }
1530 
1531     return 0;
1532 }
1533 
1534 /* From FreeBSD */
1535 /* XXX: optimize */
1536 uint32_t net_crc32(const uint8_t *p, int len)
1537 {
1538     uint32_t crc;
1539     int carry, i, j;
1540     uint8_t b;
1541 
1542     crc = 0xffffffff;
1543     for (i = 0; i < len; i++) {
1544         b = *p++;
1545         for (j = 0; j < 8; j++) {
1546             carry = ((crc & 0x80000000L) ? 1 : 0) ^ (b & 0x01);
1547             crc <<= 1;
1548             b >>= 1;
1549             if (carry) {
1550                 crc = ((crc ^ POLYNOMIAL_BE) | carry);
1551             }
1552         }
1553     }
1554 
1555     return crc;
1556 }
1557 
1558 uint32_t net_crc32_le(const uint8_t *p, int len)
1559 {
1560     uint32_t crc;
1561     int carry, i, j;
1562     uint8_t b;
1563 
1564     crc = 0xffffffff;
1565     for (i = 0; i < len; i++) {
1566         b = *p++;
1567         for (j = 0; j < 8; j++) {
1568             carry = (crc & 0x1) ^ (b & 0x01);
1569             crc >>= 1;
1570             b >>= 1;
1571             if (carry) {
1572                 crc ^= POLYNOMIAL_LE;
1573             }
1574         }
1575     }
1576 
1577     return crc;
1578 }
1579 
1580 QemuOptsList qemu_netdev_opts = {
1581     .name = "netdev",
1582     .implied_opt_name = "type",
1583     .head = QTAILQ_HEAD_INITIALIZER(qemu_netdev_opts.head),
1584     .desc = {
1585         /*
1586          * no elements => accept any params
1587          * validation will happen later
1588          */
1589         { /* end of list */ }
1590     },
1591 };
1592 
1593 QemuOptsList qemu_nic_opts = {
1594     .name = "nic",
1595     .implied_opt_name = "type",
1596     .head = QTAILQ_HEAD_INITIALIZER(qemu_nic_opts.head),
1597     .desc = {
1598         /*
1599          * no elements => accept any params
1600          * validation will happen later
1601          */
1602         { /* end of list */ }
1603     },
1604 };
1605 
1606 QemuOptsList qemu_net_opts = {
1607     .name = "net",
1608     .implied_opt_name = "type",
1609     .head = QTAILQ_HEAD_INITIALIZER(qemu_net_opts.head),
1610     .desc = {
1611         /*
1612          * no elements => accept any params
1613          * validation will happen later
1614          */
1615         { /* end of list */ }
1616     },
1617 };
1618 
1619 void net_socket_rs_init(SocketReadState *rs,
1620                         SocketReadStateFinalize *finalize,
1621                         bool vnet_hdr)
1622 {
1623     rs->state = 0;
1624     rs->vnet_hdr = vnet_hdr;
1625     rs->index = 0;
1626     rs->packet_len = 0;
1627     rs->vnet_hdr_len = 0;
1628     memset(rs->buf, 0, sizeof(rs->buf));
1629     rs->finalize = finalize;
1630 }
1631 
1632 /*
1633  * Returns
1634  * 0: success
1635  * -1: error occurs
1636  */
1637 int net_fill_rstate(SocketReadState *rs, const uint8_t *buf, int size)
1638 {
1639     unsigned int l;
1640 
1641     while (size > 0) {
1642         /* Reassemble a packet from the network.
1643          * 0 = getting length.
1644          * 1 = getting vnet header length.
1645          * 2 = getting data.
1646          */
1647         switch (rs->state) {
1648         case 0:
1649             l = 4 - rs->index;
1650             if (l > size) {
1651                 l = size;
1652             }
1653             memcpy(rs->buf + rs->index, buf, l);
1654             buf += l;
1655             size -= l;
1656             rs->index += l;
1657             if (rs->index == 4) {
1658                 /* got length */
1659                 rs->packet_len = ntohl(*(uint32_t *)rs->buf);
1660                 rs->index = 0;
1661                 if (rs->vnet_hdr) {
1662                     rs->state = 1;
1663                 } else {
1664                     rs->state = 2;
1665                     rs->vnet_hdr_len = 0;
1666                 }
1667             }
1668             break;
1669         case 1:
1670             l = 4 - rs->index;
1671             if (l > size) {
1672                 l = size;
1673             }
1674             memcpy(rs->buf + rs->index, buf, l);
1675             buf += l;
1676             size -= l;
1677             rs->index += l;
1678             if (rs->index == 4) {
1679                 /* got vnet header length */
1680                 rs->vnet_hdr_len = ntohl(*(uint32_t *)rs->buf);
1681                 rs->index = 0;
1682                 rs->state = 2;
1683             }
1684             break;
1685         case 2:
1686             l = rs->packet_len - rs->index;
1687             if (l > size) {
1688                 l = size;
1689             }
1690             if (rs->index + l <= sizeof(rs->buf)) {
1691                 memcpy(rs->buf + rs->index, buf, l);
1692             } else {
1693                 fprintf(stderr, "serious error: oversized packet received,"
1694                     "connection terminated.\n");
1695                 rs->index = rs->state = 0;
1696                 return -1;
1697             }
1698 
1699             rs->index += l;
1700             buf += l;
1701             size -= l;
1702             if (rs->index >= rs->packet_len) {
1703                 rs->index = 0;
1704                 rs->state = 0;
1705                 assert(rs->finalize);
1706                 rs->finalize(rs);
1707             }
1708             break;
1709         }
1710     }
1711 
1712     assert(size == 0);
1713     return 0;
1714 }
1715