xref: /openbmc/qemu/net/net.c (revision 14a650ec)
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 #include "config-host.h"
25 
26 #include "net/net.h"
27 #include "clients.h"
28 #include "hub.h"
29 #include "net/slirp.h"
30 #include "net/eth.h"
31 #include "util.h"
32 
33 #include "monitor/monitor.h"
34 #include "qemu-common.h"
35 #include "qemu/sockets.h"
36 #include "qemu/config-file.h"
37 #include "qmp-commands.h"
38 #include "hw/qdev.h"
39 #include "qemu/iov.h"
40 #include "qemu/main-loop.h"
41 #include "qapi-visit.h"
42 #include "qapi/opts-visitor.h"
43 #include "qapi/dealloc-visitor.h"
44 
45 /* Net bridge is currently not supported for W32. */
46 #if !defined(_WIN32)
47 # define CONFIG_NET_BRIDGE
48 #endif
49 
50 static QTAILQ_HEAD(, NetClientState) net_clients;
51 
52 int default_net = 1;
53 
54 /***********************************************************/
55 /* network device redirectors */
56 
57 #if defined(DEBUG_NET)
58 static void hex_dump(FILE *f, const uint8_t *buf, int size)
59 {
60     int len, i, j, c;
61 
62     for(i=0;i<size;i+=16) {
63         len = size - i;
64         if (len > 16)
65             len = 16;
66         fprintf(f, "%08x ", i);
67         for(j=0;j<16;j++) {
68             if (j < len)
69                 fprintf(f, " %02x", buf[i+j]);
70             else
71                 fprintf(f, "   ");
72         }
73         fprintf(f, " ");
74         for(j=0;j<len;j++) {
75             c = buf[i+j];
76             if (c < ' ' || c > '~')
77                 c = '.';
78             fprintf(f, "%c", c);
79         }
80         fprintf(f, "\n");
81     }
82 }
83 #endif
84 
85 static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
86 {
87     const char *p, *p1;
88     int len;
89     p = *pp;
90     p1 = strchr(p, sep);
91     if (!p1)
92         return -1;
93     len = p1 - p;
94     p1++;
95     if (buf_size > 0) {
96         if (len > buf_size - 1)
97             len = buf_size - 1;
98         memcpy(buf, p, len);
99         buf[len] = '\0';
100     }
101     *pp = p1;
102     return 0;
103 }
104 
105 int parse_host_port(struct sockaddr_in *saddr, const char *str)
106 {
107     char buf[512];
108     struct hostent *he;
109     const char *p, *r;
110     int port;
111 
112     p = str;
113     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0)
114         return -1;
115     saddr->sin_family = AF_INET;
116     if (buf[0] == '\0') {
117         saddr->sin_addr.s_addr = 0;
118     } else {
119         if (qemu_isdigit(buf[0])) {
120             if (!inet_aton(buf, &saddr->sin_addr))
121                 return -1;
122         } else {
123             if ((he = gethostbyname(buf)) == NULL)
124                 return - 1;
125             saddr->sin_addr = *(struct in_addr *)he->h_addr;
126         }
127     }
128     port = strtol(p, (char **)&r, 0);
129     if (r == p)
130         return -1;
131     saddr->sin_port = htons(port);
132     return 0;
133 }
134 
135 void qemu_format_nic_info_str(NetClientState *nc, uint8_t macaddr[6])
136 {
137     snprintf(nc->info_str, sizeof(nc->info_str),
138              "model=%s,macaddr=%02x:%02x:%02x:%02x:%02x:%02x",
139              nc->model,
140              macaddr[0], macaddr[1], macaddr[2],
141              macaddr[3], macaddr[4], macaddr[5]);
142 }
143 
144 void qemu_macaddr_default_if_unset(MACAddr *macaddr)
145 {
146     static int index = 0;
147     static const MACAddr zero = { .a = { 0,0,0,0,0,0 } };
148 
149     if (memcmp(macaddr, &zero, sizeof(zero)) != 0)
150         return;
151     macaddr->a[0] = 0x52;
152     macaddr->a[1] = 0x54;
153     macaddr->a[2] = 0x00;
154     macaddr->a[3] = 0x12;
155     macaddr->a[4] = 0x34;
156     macaddr->a[5] = 0x56 + index++;
157 }
158 
159 /**
160  * Generate a name for net client
161  *
162  * Only net clients created with the legacy -net option and NICs need this.
163  */
164 static char *assign_name(NetClientState *nc1, const char *model)
165 {
166     NetClientState *nc;
167     char buf[256];
168     int id = 0;
169 
170     QTAILQ_FOREACH(nc, &net_clients, next) {
171         if (nc == nc1) {
172             continue;
173         }
174         if (strcmp(nc->model, model) == 0) {
175             id++;
176         }
177     }
178 
179     snprintf(buf, sizeof(buf), "%s.%d", model, id);
180 
181     return g_strdup(buf);
182 }
183 
184 static void qemu_net_client_destructor(NetClientState *nc)
185 {
186     g_free(nc);
187 }
188 
189 static void qemu_net_client_setup(NetClientState *nc,
190                                   NetClientInfo *info,
191                                   NetClientState *peer,
192                                   const char *model,
193                                   const char *name,
194                                   NetClientDestructor *destructor)
195 {
196     nc->info = info;
197     nc->model = g_strdup(model);
198     if (name) {
199         nc->name = g_strdup(name);
200     } else {
201         nc->name = assign_name(nc, model);
202     }
203 
204     if (peer) {
205         assert(!peer->peer);
206         nc->peer = peer;
207         peer->peer = nc;
208     }
209     QTAILQ_INSERT_TAIL(&net_clients, nc, next);
210 
211     nc->incoming_queue = qemu_new_net_queue(nc);
212     nc->destructor = destructor;
213 }
214 
215 NetClientState *qemu_new_net_client(NetClientInfo *info,
216                                     NetClientState *peer,
217                                     const char *model,
218                                     const char *name)
219 {
220     NetClientState *nc;
221 
222     assert(info->size >= sizeof(NetClientState));
223 
224     nc = g_malloc0(info->size);
225     qemu_net_client_setup(nc, info, peer, model, name,
226                           qemu_net_client_destructor);
227 
228     return nc;
229 }
230 
231 NICState *qemu_new_nic(NetClientInfo *info,
232                        NICConf *conf,
233                        const char *model,
234                        const char *name,
235                        void *opaque)
236 {
237     NetClientState **peers = conf->peers.ncs;
238     NICState *nic;
239     int i, queues = MAX(1, conf->queues);
240 
241     assert(info->type == NET_CLIENT_OPTIONS_KIND_NIC);
242     assert(info->size >= sizeof(NICState));
243 
244     nic = g_malloc0(info->size + sizeof(NetClientState) * queues);
245     nic->ncs = (void *)nic + info->size;
246     nic->conf = conf;
247     nic->opaque = opaque;
248 
249     for (i = 0; i < queues; i++) {
250         qemu_net_client_setup(&nic->ncs[i], info, peers[i], model, name,
251                               NULL);
252         nic->ncs[i].queue_index = i;
253     }
254 
255     return nic;
256 }
257 
258 NetClientState *qemu_get_subqueue(NICState *nic, int queue_index)
259 {
260     return nic->ncs + queue_index;
261 }
262 
263 NetClientState *qemu_get_queue(NICState *nic)
264 {
265     return qemu_get_subqueue(nic, 0);
266 }
267 
268 NICState *qemu_get_nic(NetClientState *nc)
269 {
270     NetClientState *nc0 = nc - nc->queue_index;
271 
272     return (NICState *)((void *)nc0 - nc->info->size);
273 }
274 
275 void *qemu_get_nic_opaque(NetClientState *nc)
276 {
277     NICState *nic = qemu_get_nic(nc);
278 
279     return nic->opaque;
280 }
281 
282 static void qemu_cleanup_net_client(NetClientState *nc)
283 {
284     QTAILQ_REMOVE(&net_clients, nc, next);
285 
286     if (nc->info->cleanup) {
287         nc->info->cleanup(nc);
288     }
289 }
290 
291 static void qemu_free_net_client(NetClientState *nc)
292 {
293     if (nc->incoming_queue) {
294         qemu_del_net_queue(nc->incoming_queue);
295     }
296     if (nc->peer) {
297         nc->peer->peer = NULL;
298     }
299     g_free(nc->name);
300     g_free(nc->model);
301     if (nc->destructor) {
302         nc->destructor(nc);
303     }
304 }
305 
306 void qemu_del_net_client(NetClientState *nc)
307 {
308     NetClientState *ncs[MAX_QUEUE_NUM];
309     int queues, i;
310 
311     /* If the NetClientState belongs to a multiqueue backend, we will change all
312      * other NetClientStates also.
313      */
314     queues = qemu_find_net_clients_except(nc->name, ncs,
315                                           NET_CLIENT_OPTIONS_KIND_NIC,
316                                           MAX_QUEUE_NUM);
317     assert(queues != 0);
318 
319     /* If there is a peer NIC, delete and cleanup client, but do not free. */
320     if (nc->peer && nc->peer->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
321         NICState *nic = qemu_get_nic(nc->peer);
322         if (nic->peer_deleted) {
323             return;
324         }
325         nic->peer_deleted = true;
326 
327         for (i = 0; i < queues; i++) {
328             ncs[i]->peer->link_down = true;
329         }
330 
331         if (nc->peer->info->link_status_changed) {
332             nc->peer->info->link_status_changed(nc->peer);
333         }
334 
335         for (i = 0; i < queues; i++) {
336             qemu_cleanup_net_client(ncs[i]);
337         }
338 
339         return;
340     }
341 
342     assert(nc->info->type != NET_CLIENT_OPTIONS_KIND_NIC);
343 
344     for (i = 0; i < queues; i++) {
345         qemu_cleanup_net_client(ncs[i]);
346         qemu_free_net_client(ncs[i]);
347     }
348 }
349 
350 void qemu_del_nic(NICState *nic)
351 {
352     int i, queues = MAX(nic->conf->queues, 1);
353 
354     /* If this is a peer NIC and peer has already been deleted, free it now. */
355     if (nic->peer_deleted) {
356         for (i = 0; i < queues; i++) {
357             qemu_free_net_client(qemu_get_subqueue(nic, i)->peer);
358         }
359     }
360 
361     for (i = queues - 1; i >= 0; i--) {
362         NetClientState *nc = qemu_get_subqueue(nic, i);
363 
364         qemu_cleanup_net_client(nc);
365         qemu_free_net_client(nc);
366     }
367 
368     g_free(nic);
369 }
370 
371 void qemu_foreach_nic(qemu_nic_foreach func, void *opaque)
372 {
373     NetClientState *nc;
374 
375     QTAILQ_FOREACH(nc, &net_clients, next) {
376         if (nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
377             if (nc->queue_index == 0) {
378                 func(qemu_get_nic(nc), opaque);
379             }
380         }
381     }
382 }
383 
384 int qemu_can_send_packet(NetClientState *sender)
385 {
386     if (!sender->peer) {
387         return 1;
388     }
389 
390     if (sender->peer->receive_disabled) {
391         return 0;
392     } else if (sender->peer->info->can_receive &&
393                !sender->peer->info->can_receive(sender->peer)) {
394         return 0;
395     }
396     return 1;
397 }
398 
399 ssize_t qemu_deliver_packet(NetClientState *sender,
400                             unsigned flags,
401                             const uint8_t *data,
402                             size_t size,
403                             void *opaque)
404 {
405     NetClientState *nc = opaque;
406     ssize_t ret;
407 
408     if (nc->link_down) {
409         return size;
410     }
411 
412     if (nc->receive_disabled) {
413         return 0;
414     }
415 
416     if (flags & QEMU_NET_PACKET_FLAG_RAW && nc->info->receive_raw) {
417         ret = nc->info->receive_raw(nc, data, size);
418     } else {
419         ret = nc->info->receive(nc, data, size);
420     }
421 
422     if (ret == 0) {
423         nc->receive_disabled = 1;
424     };
425 
426     return ret;
427 }
428 
429 void qemu_purge_queued_packets(NetClientState *nc)
430 {
431     if (!nc->peer) {
432         return;
433     }
434 
435     qemu_net_queue_purge(nc->peer->incoming_queue, nc);
436 }
437 
438 void qemu_flush_queued_packets(NetClientState *nc)
439 {
440     nc->receive_disabled = 0;
441 
442     if (nc->peer && nc->peer->info->type == NET_CLIENT_OPTIONS_KIND_HUBPORT) {
443         if (net_hub_flush(nc->peer)) {
444             qemu_notify_event();
445         }
446     }
447     if (qemu_net_queue_flush(nc->incoming_queue)) {
448         /* We emptied the queue successfully, signal to the IO thread to repoll
449          * the file descriptor (for tap, for example).
450          */
451         qemu_notify_event();
452     }
453 }
454 
455 static ssize_t qemu_send_packet_async_with_flags(NetClientState *sender,
456                                                  unsigned flags,
457                                                  const uint8_t *buf, int size,
458                                                  NetPacketSent *sent_cb)
459 {
460     NetQueue *queue;
461 
462 #ifdef DEBUG_NET
463     printf("qemu_send_packet_async:\n");
464     hex_dump(stdout, buf, size);
465 #endif
466 
467     if (sender->link_down || !sender->peer) {
468         return size;
469     }
470 
471     queue = sender->peer->incoming_queue;
472 
473     return qemu_net_queue_send(queue, sender, flags, buf, size, sent_cb);
474 }
475 
476 ssize_t qemu_send_packet_async(NetClientState *sender,
477                                const uint8_t *buf, int size,
478                                NetPacketSent *sent_cb)
479 {
480     return qemu_send_packet_async_with_flags(sender, QEMU_NET_PACKET_FLAG_NONE,
481                                              buf, size, sent_cb);
482 }
483 
484 void qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size)
485 {
486     qemu_send_packet_async(nc, buf, size, NULL);
487 }
488 
489 ssize_t qemu_send_packet_raw(NetClientState *nc, const uint8_t *buf, int size)
490 {
491     return qemu_send_packet_async_with_flags(nc, QEMU_NET_PACKET_FLAG_RAW,
492                                              buf, size, NULL);
493 }
494 
495 static ssize_t nc_sendv_compat(NetClientState *nc, const struct iovec *iov,
496                                int iovcnt)
497 {
498     uint8_t buffer[NET_BUFSIZE];
499     size_t offset;
500 
501     offset = iov_to_buf(iov, iovcnt, 0, buffer, sizeof(buffer));
502 
503     return nc->info->receive(nc, buffer, offset);
504 }
505 
506 ssize_t qemu_deliver_packet_iov(NetClientState *sender,
507                                 unsigned flags,
508                                 const struct iovec *iov,
509                                 int iovcnt,
510                                 void *opaque)
511 {
512     NetClientState *nc = opaque;
513     int ret;
514 
515     if (nc->link_down) {
516         return iov_size(iov, iovcnt);
517     }
518 
519     if (nc->receive_disabled) {
520         return 0;
521     }
522 
523     if (nc->info->receive_iov) {
524         ret = nc->info->receive_iov(nc, iov, iovcnt);
525     } else {
526         ret = nc_sendv_compat(nc, iov, iovcnt);
527     }
528 
529     if (ret == 0) {
530         nc->receive_disabled = 1;
531     }
532 
533     return ret;
534 }
535 
536 ssize_t qemu_sendv_packet_async(NetClientState *sender,
537                                 const struct iovec *iov, int iovcnt,
538                                 NetPacketSent *sent_cb)
539 {
540     NetQueue *queue;
541 
542     if (sender->link_down || !sender->peer) {
543         return iov_size(iov, iovcnt);
544     }
545 
546     queue = sender->peer->incoming_queue;
547 
548     return qemu_net_queue_send_iov(queue, sender,
549                                    QEMU_NET_PACKET_FLAG_NONE,
550                                    iov, iovcnt, sent_cb);
551 }
552 
553 ssize_t
554 qemu_sendv_packet(NetClientState *nc, const struct iovec *iov, int iovcnt)
555 {
556     return qemu_sendv_packet_async(nc, iov, iovcnt, NULL);
557 }
558 
559 NetClientState *qemu_find_netdev(const char *id)
560 {
561     NetClientState *nc;
562 
563     QTAILQ_FOREACH(nc, &net_clients, next) {
564         if (nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC)
565             continue;
566         if (!strcmp(nc->name, id)) {
567             return nc;
568         }
569     }
570 
571     return NULL;
572 }
573 
574 int qemu_find_net_clients_except(const char *id, NetClientState **ncs,
575                                  NetClientOptionsKind type, int max)
576 {
577     NetClientState *nc;
578     int ret = 0;
579 
580     QTAILQ_FOREACH(nc, &net_clients, next) {
581         if (nc->info->type == type) {
582             continue;
583         }
584         if (!strcmp(nc->name, id)) {
585             if (ret < max) {
586                 ncs[ret] = nc;
587             }
588             ret++;
589         }
590     }
591 
592     return ret;
593 }
594 
595 static int nic_get_free_idx(void)
596 {
597     int index;
598 
599     for (index = 0; index < MAX_NICS; index++)
600         if (!nd_table[index].used)
601             return index;
602     return -1;
603 }
604 
605 int qemu_show_nic_models(const char *arg, const char *const *models)
606 {
607     int i;
608 
609     if (!arg || !is_help_option(arg)) {
610         return 0;
611     }
612 
613     fprintf(stderr, "qemu: Supported NIC models: ");
614     for (i = 0 ; models[i]; i++)
615         fprintf(stderr, "%s%c", models[i], models[i+1] ? ',' : '\n');
616     return 1;
617 }
618 
619 void qemu_check_nic_model(NICInfo *nd, const char *model)
620 {
621     const char *models[2];
622 
623     models[0] = model;
624     models[1] = NULL;
625 
626     if (qemu_show_nic_models(nd->model, models))
627         exit(0);
628     if (qemu_find_nic_model(nd, models, model) < 0)
629         exit(1);
630 }
631 
632 int qemu_find_nic_model(NICInfo *nd, const char * const *models,
633                         const char *default_model)
634 {
635     int i;
636 
637     if (!nd->model)
638         nd->model = g_strdup(default_model);
639 
640     for (i = 0 ; models[i]; i++) {
641         if (strcmp(nd->model, models[i]) == 0)
642             return i;
643     }
644 
645     error_report("Unsupported NIC model: %s", nd->model);
646     return -1;
647 }
648 
649 static int net_init_nic(const NetClientOptions *opts, const char *name,
650                         NetClientState *peer)
651 {
652     int idx;
653     NICInfo *nd;
654     const NetLegacyNicOptions *nic;
655 
656     assert(opts->kind == NET_CLIENT_OPTIONS_KIND_NIC);
657     nic = opts->nic;
658 
659     idx = nic_get_free_idx();
660     if (idx == -1 || nb_nics >= MAX_NICS) {
661         error_report("Too Many NICs");
662         return -1;
663     }
664 
665     nd = &nd_table[idx];
666 
667     memset(nd, 0, sizeof(*nd));
668 
669     if (nic->has_netdev) {
670         nd->netdev = qemu_find_netdev(nic->netdev);
671         if (!nd->netdev) {
672             error_report("netdev '%s' not found", nic->netdev);
673             return -1;
674         }
675     } else {
676         assert(peer);
677         nd->netdev = peer;
678     }
679     nd->name = g_strdup(name);
680     if (nic->has_model) {
681         nd->model = g_strdup(nic->model);
682     }
683     if (nic->has_addr) {
684         nd->devaddr = g_strdup(nic->addr);
685     }
686 
687     if (nic->has_macaddr &&
688         net_parse_macaddr(nd->macaddr.a, nic->macaddr) < 0) {
689         error_report("invalid syntax for ethernet address");
690         return -1;
691     }
692     if (nic->has_macaddr &&
693         is_multicast_ether_addr(nd->macaddr.a)) {
694         error_report("NIC cannot have multicast MAC address (odd 1st byte)");
695         return -1;
696     }
697     qemu_macaddr_default_if_unset(&nd->macaddr);
698 
699     if (nic->has_vectors) {
700         if (nic->vectors > 0x7ffffff) {
701             error_report("invalid # of vectors: %"PRIu32, nic->vectors);
702             return -1;
703         }
704         nd->nvectors = nic->vectors;
705     } else {
706         nd->nvectors = DEV_NVECTORS_UNSPECIFIED;
707     }
708 
709     nd->used = 1;
710     nb_nics++;
711 
712     return idx;
713 }
714 
715 
716 static int (* const net_client_init_fun[NET_CLIENT_OPTIONS_KIND_MAX])(
717     const NetClientOptions *opts,
718     const char *name,
719     NetClientState *peer) = {
720         [NET_CLIENT_OPTIONS_KIND_NIC]       = net_init_nic,
721 #ifdef CONFIG_SLIRP
722         [NET_CLIENT_OPTIONS_KIND_USER]      = net_init_slirp,
723 #endif
724         [NET_CLIENT_OPTIONS_KIND_TAP]       = net_init_tap,
725         [NET_CLIENT_OPTIONS_KIND_SOCKET]    = net_init_socket,
726 #ifdef CONFIG_VDE
727         [NET_CLIENT_OPTIONS_KIND_VDE]       = net_init_vde,
728 #endif
729         [NET_CLIENT_OPTIONS_KIND_DUMP]      = net_init_dump,
730 #ifdef CONFIG_NET_BRIDGE
731         [NET_CLIENT_OPTIONS_KIND_BRIDGE]    = net_init_bridge,
732 #endif
733         [NET_CLIENT_OPTIONS_KIND_HUBPORT]   = net_init_hubport,
734 };
735 
736 
737 static int net_client_init1(const void *object, int is_netdev, Error **errp)
738 {
739     union {
740         const Netdev    *netdev;
741         const NetLegacy *net;
742     } u;
743     const NetClientOptions *opts;
744     const char *name;
745 
746     if (is_netdev) {
747         u.netdev = object;
748         opts = u.netdev->opts;
749         name = u.netdev->id;
750 
751         switch (opts->kind) {
752 #ifdef CONFIG_SLIRP
753         case NET_CLIENT_OPTIONS_KIND_USER:
754 #endif
755         case NET_CLIENT_OPTIONS_KIND_TAP:
756         case NET_CLIENT_OPTIONS_KIND_SOCKET:
757 #ifdef CONFIG_VDE
758         case NET_CLIENT_OPTIONS_KIND_VDE:
759 #endif
760 #ifdef CONFIG_NET_BRIDGE
761         case NET_CLIENT_OPTIONS_KIND_BRIDGE:
762 #endif
763         case NET_CLIENT_OPTIONS_KIND_HUBPORT:
764             break;
765 
766         default:
767             error_set(errp, QERR_INVALID_PARAMETER_VALUE, "type",
768                       "a netdev backend type");
769             return -1;
770         }
771     } else {
772         u.net = object;
773         opts = u.net->opts;
774         /* missing optional values have been initialized to "all bits zero" */
775         name = u.net->has_id ? u.net->id : u.net->name;
776     }
777 
778     if (net_client_init_fun[opts->kind]) {
779         NetClientState *peer = NULL;
780 
781         /* Do not add to a vlan if it's a -netdev or a nic with a netdev=
782          * parameter. */
783         if (!is_netdev &&
784             (opts->kind != NET_CLIENT_OPTIONS_KIND_NIC ||
785              !opts->nic->has_netdev)) {
786             peer = net_hub_add_port(u.net->has_vlan ? u.net->vlan : 0, NULL);
787         }
788 
789         if (net_client_init_fun[opts->kind](opts, name, peer) < 0) {
790             /* TODO push error reporting into init() methods */
791             error_set(errp, QERR_DEVICE_INIT_FAILED,
792                       NetClientOptionsKind_lookup[opts->kind]);
793             return -1;
794         }
795     }
796     return 0;
797 }
798 
799 
800 static void net_visit(Visitor *v, int is_netdev, void **object, Error **errp)
801 {
802     if (is_netdev) {
803         visit_type_Netdev(v, (Netdev **)object, NULL, errp);
804     } else {
805         visit_type_NetLegacy(v, (NetLegacy **)object, NULL, errp);
806     }
807 }
808 
809 
810 int net_client_init(QemuOpts *opts, int is_netdev, Error **errp)
811 {
812     void *object = NULL;
813     Error *err = NULL;
814     int ret = -1;
815 
816     {
817         OptsVisitor *ov = opts_visitor_new(opts);
818 
819         net_visit(opts_get_visitor(ov), is_netdev, &object, &err);
820         opts_visitor_cleanup(ov);
821     }
822 
823     if (!err) {
824         ret = net_client_init1(object, is_netdev, &err);
825     }
826 
827     if (object) {
828         QapiDeallocVisitor *dv = qapi_dealloc_visitor_new();
829 
830         net_visit(qapi_dealloc_get_visitor(dv), is_netdev, &object, NULL);
831         qapi_dealloc_visitor_cleanup(dv);
832     }
833 
834     error_propagate(errp, err);
835     return ret;
836 }
837 
838 
839 static int net_host_check_device(const char *device)
840 {
841     int i;
842     const char *valid_param_list[] = { "tap", "socket", "dump"
843 #ifdef CONFIG_NET_BRIDGE
844                                        , "bridge"
845 #endif
846 #ifdef CONFIG_SLIRP
847                                        ,"user"
848 #endif
849 #ifdef CONFIG_VDE
850                                        ,"vde"
851 #endif
852     };
853     for (i = 0; i < sizeof(valid_param_list) / sizeof(char *); i++) {
854         if (!strncmp(valid_param_list[i], device,
855                      strlen(valid_param_list[i])))
856             return 1;
857     }
858 
859     return 0;
860 }
861 
862 void net_host_device_add(Monitor *mon, const QDict *qdict)
863 {
864     const char *device = qdict_get_str(qdict, "device");
865     const char *opts_str = qdict_get_try_str(qdict, "opts");
866     Error *local_err = NULL;
867     QemuOpts *opts;
868 
869     if (!net_host_check_device(device)) {
870         monitor_printf(mon, "invalid host network device %s\n", device);
871         return;
872     }
873 
874     opts = qemu_opts_parse(qemu_find_opts("net"), opts_str ? opts_str : "", 0);
875     if (!opts) {
876         return;
877     }
878 
879     qemu_opt_set(opts, "type", device);
880 
881     net_client_init(opts, 0, &local_err);
882     if (error_is_set(&local_err)) {
883         qerror_report_err(local_err);
884         error_free(local_err);
885         monitor_printf(mon, "adding host network device %s failed\n", device);
886     }
887 }
888 
889 void net_host_device_remove(Monitor *mon, const QDict *qdict)
890 {
891     NetClientState *nc;
892     int vlan_id = qdict_get_int(qdict, "vlan_id");
893     const char *device = qdict_get_str(qdict, "device");
894 
895     nc = net_hub_find_client_by_name(vlan_id, device);
896     if (!nc) {
897         return;
898     }
899     if (!net_host_check_device(nc->model)) {
900         monitor_printf(mon, "invalid host network device %s\n", device);
901         return;
902     }
903     qemu_del_net_client(nc);
904 }
905 
906 void netdev_add(QemuOpts *opts, Error **errp)
907 {
908     net_client_init(opts, 1, errp);
909 }
910 
911 int qmp_netdev_add(Monitor *mon, const QDict *qdict, QObject **ret)
912 {
913     Error *local_err = NULL;
914     QemuOptsList *opts_list;
915     QemuOpts *opts;
916 
917     opts_list = qemu_find_opts_err("netdev", &local_err);
918     if (error_is_set(&local_err)) {
919         goto exit_err;
920     }
921 
922     opts = qemu_opts_from_qdict(opts_list, qdict, &local_err);
923     if (error_is_set(&local_err)) {
924         goto exit_err;
925     }
926 
927     netdev_add(opts, &local_err);
928     if (error_is_set(&local_err)) {
929         qemu_opts_del(opts);
930         goto exit_err;
931     }
932 
933     return 0;
934 
935 exit_err:
936     qerror_report_err(local_err);
937     error_free(local_err);
938     return -1;
939 }
940 
941 void qmp_netdev_del(const char *id, Error **errp)
942 {
943     NetClientState *nc;
944     QemuOpts *opts;
945 
946     nc = qemu_find_netdev(id);
947     if (!nc) {
948         error_set(errp, QERR_DEVICE_NOT_FOUND, id);
949         return;
950     }
951 
952     opts = qemu_opts_find(qemu_find_opts_err("netdev", NULL), id);
953     if (!opts) {
954         error_setg(errp, "Device '%s' is not a netdev", id);
955         return;
956     }
957 
958     qemu_del_net_client(nc);
959     qemu_opts_del(opts);
960 }
961 
962 void print_net_client(Monitor *mon, NetClientState *nc)
963 {
964     monitor_printf(mon, "%s: index=%d,type=%s,%s\n", nc->name,
965                    nc->queue_index,
966                    NetClientOptionsKind_lookup[nc->info->type],
967                    nc->info_str);
968 }
969 
970 RxFilterInfoList *qmp_query_rx_filter(bool has_name, const char *name,
971                                       Error **errp)
972 {
973     NetClientState *nc;
974     RxFilterInfoList *filter_list = NULL, *last_entry = NULL;
975 
976     QTAILQ_FOREACH(nc, &net_clients, next) {
977         RxFilterInfoList *entry;
978         RxFilterInfo *info;
979 
980         if (has_name && strcmp(nc->name, name) != 0) {
981             continue;
982         }
983 
984         /* only query rx-filter information of NIC */
985         if (nc->info->type != NET_CLIENT_OPTIONS_KIND_NIC) {
986             if (has_name) {
987                 error_setg(errp, "net client(%s) isn't a NIC", name);
988                 break;
989             }
990             continue;
991         }
992 
993         if (nc->info->query_rx_filter) {
994             info = nc->info->query_rx_filter(nc);
995             entry = g_malloc0(sizeof(*entry));
996             entry->value = info;
997 
998             if (!filter_list) {
999                 filter_list = entry;
1000             } else {
1001                 last_entry->next = entry;
1002             }
1003             last_entry = entry;
1004         } else if (has_name) {
1005             error_setg(errp, "net client(%s) doesn't support"
1006                        " rx-filter querying", name);
1007             break;
1008         }
1009     }
1010 
1011     if (filter_list == NULL && !error_is_set(errp) && has_name) {
1012         error_setg(errp, "invalid net client name: %s", name);
1013     }
1014 
1015     return filter_list;
1016 }
1017 
1018 void do_info_network(Monitor *mon, const QDict *qdict)
1019 {
1020     NetClientState *nc, *peer;
1021     NetClientOptionsKind type;
1022 
1023     net_hub_info(mon);
1024 
1025     QTAILQ_FOREACH(nc, &net_clients, next) {
1026         peer = nc->peer;
1027         type = nc->info->type;
1028 
1029         /* Skip if already printed in hub info */
1030         if (net_hub_id_for_client(nc, NULL) == 0) {
1031             continue;
1032         }
1033 
1034         if (!peer || type == NET_CLIENT_OPTIONS_KIND_NIC) {
1035             print_net_client(mon, nc);
1036         } /* else it's a netdev connected to a NIC, printed with the NIC */
1037         if (peer && type == NET_CLIENT_OPTIONS_KIND_NIC) {
1038             monitor_printf(mon, " \\ ");
1039             print_net_client(mon, peer);
1040         }
1041     }
1042 }
1043 
1044 void qmp_set_link(const char *name, bool up, Error **errp)
1045 {
1046     NetClientState *ncs[MAX_QUEUE_NUM];
1047     NetClientState *nc;
1048     int queues, i;
1049 
1050     queues = qemu_find_net_clients_except(name, ncs,
1051                                           NET_CLIENT_OPTIONS_KIND_MAX,
1052                                           MAX_QUEUE_NUM);
1053 
1054     if (queues == 0) {
1055         error_set(errp, QERR_DEVICE_NOT_FOUND, name);
1056         return;
1057     }
1058     nc = ncs[0];
1059 
1060     for (i = 0; i < queues; i++) {
1061         ncs[i]->link_down = !up;
1062     }
1063 
1064     if (nc->info->link_status_changed) {
1065         nc->info->link_status_changed(nc);
1066     }
1067 
1068     /* Notify peer. Don't update peer link status: this makes it possible to
1069      * disconnect from host network without notifying the guest.
1070      * FIXME: is disconnected link status change operation useful?
1071      *
1072      * Current behaviour is compatible with qemu vlans where there could be
1073      * multiple clients that can still communicate with each other in
1074      * disconnected mode. For now maintain this compatibility. */
1075     if (nc->peer && nc->peer->info->link_status_changed) {
1076         nc->peer->info->link_status_changed(nc->peer);
1077     }
1078 }
1079 
1080 void net_cleanup(void)
1081 {
1082     NetClientState *nc;
1083 
1084     /* We may del multiple entries during qemu_del_net_client(),
1085      * so QTAILQ_FOREACH_SAFE() is also not safe here.
1086      */
1087     while (!QTAILQ_EMPTY(&net_clients)) {
1088         nc = QTAILQ_FIRST(&net_clients);
1089         if (nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
1090             qemu_del_nic(qemu_get_nic(nc));
1091         } else {
1092             qemu_del_net_client(nc);
1093         }
1094     }
1095 }
1096 
1097 void net_check_clients(void)
1098 {
1099     NetClientState *nc;
1100     int i;
1101 
1102     /* Don't warn about the default network setup that you get if
1103      * no command line -net or -netdev options are specified. There
1104      * are two cases that we would otherwise complain about:
1105      * (1) board doesn't support a NIC but the implicit "-net nic"
1106      * requested one
1107      * (2) CONFIG_SLIRP not set, in which case the implicit "-net nic"
1108      * sets up a nic that isn't connected to anything.
1109      */
1110     if (default_net) {
1111         return;
1112     }
1113 
1114     net_hub_check_clients();
1115 
1116     QTAILQ_FOREACH(nc, &net_clients, next) {
1117         if (!nc->peer) {
1118             fprintf(stderr, "Warning: %s %s has no peer\n",
1119                     nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC ?
1120                     "nic" : "netdev", nc->name);
1121         }
1122     }
1123 
1124     /* Check that all NICs requested via -net nic actually got created.
1125      * NICs created via -device don't need to be checked here because
1126      * they are always instantiated.
1127      */
1128     for (i = 0; i < MAX_NICS; i++) {
1129         NICInfo *nd = &nd_table[i];
1130         if (nd->used && !nd->instantiated) {
1131             fprintf(stderr, "Warning: requested NIC (%s, model %s) "
1132                     "was not created (not supported by this machine?)\n",
1133                     nd->name ? nd->name : "anonymous",
1134                     nd->model ? nd->model : "unspecified");
1135         }
1136     }
1137 }
1138 
1139 static int net_init_client(QemuOpts *opts, void *dummy)
1140 {
1141     Error *local_err = NULL;
1142 
1143     net_client_init(opts, 0, &local_err);
1144     if (error_is_set(&local_err)) {
1145         qerror_report_err(local_err);
1146         error_free(local_err);
1147         return -1;
1148     }
1149 
1150     return 0;
1151 }
1152 
1153 static int net_init_netdev(QemuOpts *opts, void *dummy)
1154 {
1155     Error *local_err = NULL;
1156     int ret;
1157 
1158     ret = net_client_init(opts, 1, &local_err);
1159     if (error_is_set(&local_err)) {
1160         qerror_report_err(local_err);
1161         error_free(local_err);
1162         return -1;
1163     }
1164 
1165     return ret;
1166 }
1167 
1168 int net_init_clients(void)
1169 {
1170     QemuOptsList *net = qemu_find_opts("net");
1171 
1172     if (default_net) {
1173         /* if no clients, we use a default config */
1174         qemu_opts_set(net, NULL, "type", "nic");
1175 #ifdef CONFIG_SLIRP
1176         qemu_opts_set(net, NULL, "type", "user");
1177 #endif
1178     }
1179 
1180     QTAILQ_INIT(&net_clients);
1181 
1182     if (qemu_opts_foreach(qemu_find_opts("netdev"), net_init_netdev, NULL, 1) == -1)
1183         return -1;
1184 
1185     if (qemu_opts_foreach(net, net_init_client, NULL, 1) == -1) {
1186         return -1;
1187     }
1188 
1189     return 0;
1190 }
1191 
1192 int net_client_parse(QemuOptsList *opts_list, const char *optarg)
1193 {
1194 #if defined(CONFIG_SLIRP)
1195     int ret;
1196     if (net_slirp_parse_legacy(opts_list, optarg, &ret)) {
1197         return ret;
1198     }
1199 #endif
1200 
1201     if (!qemu_opts_parse(opts_list, optarg, 1)) {
1202         return -1;
1203     }
1204 
1205     default_net = 0;
1206     return 0;
1207 }
1208 
1209 /* From FreeBSD */
1210 /* XXX: optimize */
1211 unsigned compute_mcast_idx(const uint8_t *ep)
1212 {
1213     uint32_t crc;
1214     int carry, i, j;
1215     uint8_t b;
1216 
1217     crc = 0xffffffff;
1218     for (i = 0; i < 6; i++) {
1219         b = *ep++;
1220         for (j = 0; j < 8; j++) {
1221             carry = ((crc & 0x80000000L) ? 1 : 0) ^ (b & 0x01);
1222             crc <<= 1;
1223             b >>= 1;
1224             if (carry) {
1225                 crc = ((crc ^ POLYNOMIAL) | carry);
1226             }
1227         }
1228     }
1229     return crc >> 26;
1230 }
1231 
1232 QemuOptsList qemu_netdev_opts = {
1233     .name = "netdev",
1234     .implied_opt_name = "type",
1235     .head = QTAILQ_HEAD_INITIALIZER(qemu_netdev_opts.head),
1236     .desc = {
1237         /*
1238          * no elements => accept any params
1239          * validation will happen later
1240          */
1241         { /* end of list */ }
1242     },
1243 };
1244 
1245 QemuOptsList qemu_net_opts = {
1246     .name = "net",
1247     .implied_opt_name = "type",
1248     .head = QTAILQ_HEAD_INITIALIZER(qemu_net_opts.head),
1249     .desc = {
1250         /*
1251          * no elements => accept any params
1252          * validation will happen later
1253          */
1254         { /* end of list */ }
1255     },
1256 };
1257