xref: /openbmc/qemu/net/net.c (revision 354908ce)
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/iov.h"
47 #include "qemu/main-loop.h"
48 #include "qemu/option.h"
49 #include "qapi/error.h"
50 #include "qapi/opts-visitor.h"
51 #include "sysemu/sysemu.h"
52 #include "sysemu/qtest.h"
53 #include "sysemu/runstate.h"
54 #include "sysemu/sysemu.h"
55 #include "net/filter.h"
56 #include "qapi/string-output-visitor.h"
57 
58 /* Net bridge is currently not supported for W32. */
59 #if !defined(_WIN32)
60 # define CONFIG_NET_BRIDGE
61 #endif
62 
63 static VMChangeStateEntry *net_change_state_entry;
64 static QTAILQ_HEAD(, NetClientState) net_clients;
65 
66 /***********************************************************/
67 /* network device redirectors */
68 
69 int parse_host_port(struct sockaddr_in *saddr, const char *str,
70                     Error **errp)
71 {
72     gchar **substrings;
73     struct hostent *he;
74     const char *addr, *p, *r;
75     int port, ret = 0;
76 
77     substrings = g_strsplit(str, ":", 2);
78     if (!substrings || !substrings[0] || !substrings[1]) {
79         error_setg(errp, "host address '%s' doesn't contain ':' "
80                    "separating host from port", str);
81         ret = -1;
82         goto out;
83     }
84 
85     addr = substrings[0];
86     p = substrings[1];
87 
88     saddr->sin_family = AF_INET;
89     if (addr[0] == '\0') {
90         saddr->sin_addr.s_addr = 0;
91     } else {
92         if (qemu_isdigit(addr[0])) {
93             if (!inet_aton(addr, &saddr->sin_addr)) {
94                 error_setg(errp, "host address '%s' is not a valid "
95                            "IPv4 address", addr);
96                 ret = -1;
97                 goto out;
98             }
99         } else {
100             he = gethostbyname(addr);
101             if (he == NULL) {
102                 error_setg(errp, "can't resolve host address '%s'", addr);
103                 ret = -1;
104                 goto out;
105             }
106             saddr->sin_addr = *(struct in_addr *)he->h_addr;
107         }
108     }
109     port = strtol(p, (char **)&r, 0);
110     if (r == p) {
111         error_setg(errp, "port number '%s' is invalid", p);
112         ret = -1;
113         goto out;
114     }
115     saddr->sin_port = htons(port);
116 
117 out:
118     g_strfreev(substrings);
119     return ret;
120 }
121 
122 char *qemu_mac_strdup_printf(const uint8_t *macaddr)
123 {
124     return g_strdup_printf("%.2x:%.2x:%.2x:%.2x:%.2x:%.2x",
125                            macaddr[0], macaddr[1], macaddr[2],
126                            macaddr[3], macaddr[4], macaddr[5]);
127 }
128 
129 void qemu_format_nic_info_str(NetClientState *nc, uint8_t macaddr[6])
130 {
131     snprintf(nc->info_str, sizeof(nc->info_str),
132              "model=%s,macaddr=%02x:%02x:%02x:%02x:%02x:%02x",
133              nc->model,
134              macaddr[0], macaddr[1], macaddr[2],
135              macaddr[3], macaddr[4], macaddr[5]);
136 }
137 
138 static int mac_table[256] = {0};
139 
140 static void qemu_macaddr_set_used(MACAddr *macaddr)
141 {
142     int index;
143 
144     for (index = 0x56; index < 0xFF; index++) {
145         if (macaddr->a[5] == index) {
146             mac_table[index]++;
147         }
148     }
149 }
150 
151 static void qemu_macaddr_set_free(MACAddr *macaddr)
152 {
153     int index;
154     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
155 
156     if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
157         return;
158     }
159     for (index = 0x56; index < 0xFF; index++) {
160         if (macaddr->a[5] == index) {
161             mac_table[index]--;
162         }
163     }
164 }
165 
166 static int qemu_macaddr_get_free(void)
167 {
168     int index;
169 
170     for (index = 0x56; index < 0xFF; index++) {
171         if (mac_table[index] == 0) {
172             return index;
173         }
174     }
175 
176     return -1;
177 }
178 
179 void qemu_macaddr_default_if_unset(MACAddr *macaddr)
180 {
181     static const MACAddr zero = { .a = { 0,0,0,0,0,0 } };
182     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
183 
184     if (memcmp(macaddr, &zero, sizeof(zero)) != 0) {
185         if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
186             return;
187         } else {
188             qemu_macaddr_set_used(macaddr);
189             return;
190         }
191     }
192 
193     macaddr->a[0] = 0x52;
194     macaddr->a[1] = 0x54;
195     macaddr->a[2] = 0x00;
196     macaddr->a[3] = 0x12;
197     macaddr->a[4] = 0x34;
198     macaddr->a[5] = qemu_macaddr_get_free();
199     qemu_macaddr_set_used(macaddr);
200 }
201 
202 /**
203  * Generate a name for net client
204  *
205  * Only net clients created with the legacy -net option and NICs need this.
206  */
207 static char *assign_name(NetClientState *nc1, const char *model)
208 {
209     NetClientState *nc;
210     int id = 0;
211 
212     QTAILQ_FOREACH(nc, &net_clients, next) {
213         if (nc == nc1) {
214             continue;
215         }
216         if (strcmp(nc->model, model) == 0) {
217             id++;
218         }
219     }
220 
221     return g_strdup_printf("%s.%d", model, id);
222 }
223 
224 static void qemu_net_client_destructor(NetClientState *nc)
225 {
226     g_free(nc);
227 }
228 static ssize_t qemu_deliver_packet_iov(NetClientState *sender,
229                                        unsigned flags,
230                                        const struct iovec *iov,
231                                        int iovcnt,
232                                        void *opaque);
233 
234 static void qemu_net_client_setup(NetClientState *nc,
235                                   NetClientInfo *info,
236                                   NetClientState *peer,
237                                   const char *model,
238                                   const char *name,
239                                   NetClientDestructor *destructor)
240 {
241     nc->info = info;
242     nc->model = g_strdup(model);
243     if (name) {
244         nc->name = g_strdup(name);
245     } else {
246         nc->name = assign_name(nc, model);
247     }
248 
249     if (peer) {
250         assert(!peer->peer);
251         nc->peer = peer;
252         peer->peer = nc;
253     }
254     QTAILQ_INSERT_TAIL(&net_clients, nc, next);
255 
256     nc->incoming_queue = qemu_new_net_queue(qemu_deliver_packet_iov, nc);
257     nc->destructor = destructor;
258     QTAILQ_INIT(&nc->filters);
259 }
260 
261 NetClientState *qemu_new_net_client(NetClientInfo *info,
262                                     NetClientState *peer,
263                                     const char *model,
264                                     const char *name)
265 {
266     NetClientState *nc;
267 
268     assert(info->size >= sizeof(NetClientState));
269 
270     nc = g_malloc0(info->size);
271     qemu_net_client_setup(nc, info, peer, model, name,
272                           qemu_net_client_destructor);
273 
274     return nc;
275 }
276 
277 NICState *qemu_new_nic(NetClientInfo *info,
278                        NICConf *conf,
279                        const char *model,
280                        const char *name,
281                        void *opaque)
282 {
283     NetClientState **peers = conf->peers.ncs;
284     NICState *nic;
285     int i, queues = MAX(1, conf->peers.queues);
286 
287     assert(info->type == NET_CLIENT_DRIVER_NIC);
288     assert(info->size >= sizeof(NICState));
289 
290     nic = g_malloc0(info->size + sizeof(NetClientState) * queues);
291     nic->ncs = (void *)nic + info->size;
292     nic->conf = conf;
293     nic->opaque = opaque;
294 
295     for (i = 0; i < queues; i++) {
296         qemu_net_client_setup(&nic->ncs[i], info, peers[i], model, name,
297                               NULL);
298         nic->ncs[i].queue_index = i;
299     }
300 
301     return nic;
302 }
303 
304 NetClientState *qemu_get_subqueue(NICState *nic, int queue_index)
305 {
306     return nic->ncs + queue_index;
307 }
308 
309 NetClientState *qemu_get_queue(NICState *nic)
310 {
311     return qemu_get_subqueue(nic, 0);
312 }
313 
314 NICState *qemu_get_nic(NetClientState *nc)
315 {
316     NetClientState *nc0 = nc - nc->queue_index;
317 
318     return (NICState *)((void *)nc0 - nc->info->size);
319 }
320 
321 void *qemu_get_nic_opaque(NetClientState *nc)
322 {
323     NICState *nic = qemu_get_nic(nc);
324 
325     return nic->opaque;
326 }
327 
328 static void qemu_cleanup_net_client(NetClientState *nc)
329 {
330     QTAILQ_REMOVE(&net_clients, nc, next);
331 
332     if (nc->info->cleanup) {
333         nc->info->cleanup(nc);
334     }
335 }
336 
337 static void qemu_free_net_client(NetClientState *nc)
338 {
339     if (nc->incoming_queue) {
340         qemu_del_net_queue(nc->incoming_queue);
341     }
342     if (nc->peer) {
343         nc->peer->peer = NULL;
344     }
345     g_free(nc->name);
346     g_free(nc->model);
347     if (nc->destructor) {
348         nc->destructor(nc);
349     }
350 }
351 
352 void qemu_del_net_client(NetClientState *nc)
353 {
354     NetClientState *ncs[MAX_QUEUE_NUM];
355     int queues, i;
356     NetFilterState *nf, *next;
357 
358     assert(nc->info->type != NET_CLIENT_DRIVER_NIC);
359 
360     /* If the NetClientState belongs to a multiqueue backend, we will change all
361      * other NetClientStates also.
362      */
363     queues = qemu_find_net_clients_except(nc->name, ncs,
364                                           NET_CLIENT_DRIVER_NIC,
365                                           MAX_QUEUE_NUM);
366     assert(queues != 0);
367 
368     QTAILQ_FOREACH_SAFE(nf, &nc->filters, next, next) {
369         object_unparent(OBJECT(nf));
370     }
371 
372     /* If there is a peer NIC, delete and cleanup client, but do not free. */
373     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
374         NICState *nic = qemu_get_nic(nc->peer);
375         if (nic->peer_deleted) {
376             return;
377         }
378         nic->peer_deleted = true;
379 
380         for (i = 0; i < queues; i++) {
381             ncs[i]->peer->link_down = true;
382         }
383 
384         if (nc->peer->info->link_status_changed) {
385             nc->peer->info->link_status_changed(nc->peer);
386         }
387 
388         for (i = 0; i < queues; i++) {
389             qemu_cleanup_net_client(ncs[i]);
390         }
391 
392         return;
393     }
394 
395     for (i = 0; i < queues; i++) {
396         qemu_cleanup_net_client(ncs[i]);
397         qemu_free_net_client(ncs[i]);
398     }
399 }
400 
401 void qemu_del_nic(NICState *nic)
402 {
403     int i, queues = MAX(nic->conf->peers.queues, 1);
404 
405     qemu_macaddr_set_free(&nic->conf->macaddr);
406 
407     /* If this is a peer NIC and peer has already been deleted, free it now. */
408     if (nic->peer_deleted) {
409         for (i = 0; i < queues; i++) {
410             qemu_free_net_client(qemu_get_subqueue(nic, i)->peer);
411         }
412     }
413 
414     for (i = queues - 1; i >= 0; i--) {
415         NetClientState *nc = qemu_get_subqueue(nic, i);
416 
417         qemu_cleanup_net_client(nc);
418         qemu_free_net_client(nc);
419     }
420 
421     g_free(nic);
422 }
423 
424 void qemu_foreach_nic(qemu_nic_foreach func, void *opaque)
425 {
426     NetClientState *nc;
427 
428     QTAILQ_FOREACH(nc, &net_clients, next) {
429         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
430             if (nc->queue_index == 0) {
431                 func(qemu_get_nic(nc), opaque);
432             }
433         }
434     }
435 }
436 
437 bool qemu_has_ufo(NetClientState *nc)
438 {
439     if (!nc || !nc->info->has_ufo) {
440         return false;
441     }
442 
443     return nc->info->has_ufo(nc);
444 }
445 
446 bool qemu_has_vnet_hdr(NetClientState *nc)
447 {
448     if (!nc || !nc->info->has_vnet_hdr) {
449         return false;
450     }
451 
452     return nc->info->has_vnet_hdr(nc);
453 }
454 
455 bool qemu_has_vnet_hdr_len(NetClientState *nc, int len)
456 {
457     if (!nc || !nc->info->has_vnet_hdr_len) {
458         return false;
459     }
460 
461     return nc->info->has_vnet_hdr_len(nc, len);
462 }
463 
464 void qemu_using_vnet_hdr(NetClientState *nc, bool enable)
465 {
466     if (!nc || !nc->info->using_vnet_hdr) {
467         return;
468     }
469 
470     nc->info->using_vnet_hdr(nc, enable);
471 }
472 
473 void qemu_set_offload(NetClientState *nc, int csum, int tso4, int tso6,
474                           int ecn, int ufo)
475 {
476     if (!nc || !nc->info->set_offload) {
477         return;
478     }
479 
480     nc->info->set_offload(nc, csum, tso4, tso6, ecn, ufo);
481 }
482 
483 void qemu_set_vnet_hdr_len(NetClientState *nc, int len)
484 {
485     if (!nc || !nc->info->set_vnet_hdr_len) {
486         return;
487     }
488 
489     nc->vnet_hdr_len = len;
490     nc->info->set_vnet_hdr_len(nc, len);
491 }
492 
493 int qemu_set_vnet_le(NetClientState *nc, bool is_le)
494 {
495 #ifdef HOST_WORDS_BIGENDIAN
496     if (!nc || !nc->info->set_vnet_le) {
497         return -ENOSYS;
498     }
499 
500     return nc->info->set_vnet_le(nc, is_le);
501 #else
502     return 0;
503 #endif
504 }
505 
506 int qemu_set_vnet_be(NetClientState *nc, bool is_be)
507 {
508 #ifdef HOST_WORDS_BIGENDIAN
509     return 0;
510 #else
511     if (!nc || !nc->info->set_vnet_be) {
512         return -ENOSYS;
513     }
514 
515     return nc->info->set_vnet_be(nc, is_be);
516 #endif
517 }
518 
519 int qemu_can_send_packet(NetClientState *sender)
520 {
521     int vm_running = runstate_is_running();
522 
523     if (!vm_running) {
524         return 0;
525     }
526 
527     if (!sender->peer) {
528         return 1;
529     }
530 
531     if (sender->peer->receive_disabled) {
532         return 0;
533     } else if (sender->peer->info->can_receive &&
534                !sender->peer->info->can_receive(sender->peer)) {
535         return 0;
536     }
537     return 1;
538 }
539 
540 static ssize_t filter_receive_iov(NetClientState *nc,
541                                   NetFilterDirection direction,
542                                   NetClientState *sender,
543                                   unsigned flags,
544                                   const struct iovec *iov,
545                                   int iovcnt,
546                                   NetPacketSent *sent_cb)
547 {
548     ssize_t ret = 0;
549     NetFilterState *nf = NULL;
550 
551     if (direction == NET_FILTER_DIRECTION_TX) {
552         QTAILQ_FOREACH(nf, &nc->filters, next) {
553             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
554                                          iovcnt, sent_cb);
555             if (ret) {
556                 return ret;
557             }
558         }
559     } else {
560         QTAILQ_FOREACH_REVERSE(nf, &nc->filters, next) {
561             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
562                                          iovcnt, sent_cb);
563             if (ret) {
564                 return ret;
565             }
566         }
567     }
568 
569     return ret;
570 }
571 
572 static ssize_t filter_receive(NetClientState *nc,
573                               NetFilterDirection direction,
574                               NetClientState *sender,
575                               unsigned flags,
576                               const uint8_t *data,
577                               size_t size,
578                               NetPacketSent *sent_cb)
579 {
580     struct iovec iov = {
581         .iov_base = (void *)data,
582         .iov_len = size
583     };
584 
585     return filter_receive_iov(nc, direction, sender, flags, &iov, 1, sent_cb);
586 }
587 
588 void qemu_purge_queued_packets(NetClientState *nc)
589 {
590     if (!nc->peer) {
591         return;
592     }
593 
594     qemu_net_queue_purge(nc->peer->incoming_queue, nc);
595 }
596 
597 void qemu_flush_or_purge_queued_packets(NetClientState *nc, bool purge)
598 {
599     nc->receive_disabled = 0;
600 
601     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_HUBPORT) {
602         if (net_hub_flush(nc->peer)) {
603             qemu_notify_event();
604         }
605     }
606     if (qemu_net_queue_flush(nc->incoming_queue)) {
607         /* We emptied the queue successfully, signal to the IO thread to repoll
608          * the file descriptor (for tap, for example).
609          */
610         qemu_notify_event();
611     } else if (purge) {
612         /* Unable to empty the queue, purge remaining packets */
613         qemu_net_queue_purge(nc->incoming_queue, nc->peer);
614     }
615 }
616 
617 void qemu_flush_queued_packets(NetClientState *nc)
618 {
619     qemu_flush_or_purge_queued_packets(nc, false);
620 }
621 
622 static ssize_t qemu_send_packet_async_with_flags(NetClientState *sender,
623                                                  unsigned flags,
624                                                  const uint8_t *buf, int size,
625                                                  NetPacketSent *sent_cb)
626 {
627     NetQueue *queue;
628     int ret;
629 
630 #ifdef DEBUG_NET
631     printf("qemu_send_packet_async:\n");
632     qemu_hexdump((const char *)buf, stdout, "net", size);
633 #endif
634 
635     if (sender->link_down || !sender->peer) {
636         return size;
637     }
638 
639     /* Let filters handle the packet first */
640     ret = filter_receive(sender, NET_FILTER_DIRECTION_TX,
641                          sender, flags, buf, size, sent_cb);
642     if (ret) {
643         return ret;
644     }
645 
646     ret = filter_receive(sender->peer, NET_FILTER_DIRECTION_RX,
647                          sender, flags, buf, size, sent_cb);
648     if (ret) {
649         return ret;
650     }
651 
652     queue = sender->peer->incoming_queue;
653 
654     return qemu_net_queue_send(queue, sender, flags, buf, size, sent_cb);
655 }
656 
657 ssize_t qemu_send_packet_async(NetClientState *sender,
658                                const uint8_t *buf, int size,
659                                NetPacketSent *sent_cb)
660 {
661     return qemu_send_packet_async_with_flags(sender, QEMU_NET_PACKET_FLAG_NONE,
662                                              buf, size, sent_cb);
663 }
664 
665 ssize_t qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size)
666 {
667     return qemu_send_packet_async(nc, buf, size, NULL);
668 }
669 
670 ssize_t qemu_send_packet_raw(NetClientState *nc, const uint8_t *buf, int size)
671 {
672     return qemu_send_packet_async_with_flags(nc, QEMU_NET_PACKET_FLAG_RAW,
673                                              buf, size, NULL);
674 }
675 
676 static ssize_t nc_sendv_compat(NetClientState *nc, const struct iovec *iov,
677                                int iovcnt, unsigned flags)
678 {
679     uint8_t *buf = NULL;
680     uint8_t *buffer;
681     size_t offset;
682     ssize_t ret;
683 
684     if (iovcnt == 1) {
685         buffer = iov[0].iov_base;
686         offset = iov[0].iov_len;
687     } else {
688         offset = iov_size(iov, iovcnt);
689         if (offset > NET_BUFSIZE) {
690             return -1;
691         }
692         buf = g_malloc(offset);
693         buffer = buf;
694         offset = iov_to_buf(iov, iovcnt, 0, buf, offset);
695     }
696 
697     if (flags & QEMU_NET_PACKET_FLAG_RAW && nc->info->receive_raw) {
698         ret = nc->info->receive_raw(nc, buffer, offset);
699     } else {
700         ret = nc->info->receive(nc, buffer, offset);
701     }
702 
703     g_free(buf);
704     return ret;
705 }
706 
707 static ssize_t qemu_deliver_packet_iov(NetClientState *sender,
708                                        unsigned flags,
709                                        const struct iovec *iov,
710                                        int iovcnt,
711                                        void *opaque)
712 {
713     NetClientState *nc = opaque;
714     int ret;
715 
716 
717     if (nc->link_down) {
718         return iov_size(iov, iovcnt);
719     }
720 
721     if (nc->receive_disabled) {
722         return 0;
723     }
724 
725     if (nc->info->receive_iov && !(flags & QEMU_NET_PACKET_FLAG_RAW)) {
726         ret = nc->info->receive_iov(nc, iov, iovcnt);
727     } else {
728         ret = nc_sendv_compat(nc, iov, iovcnt, flags);
729     }
730 
731     if (ret == 0) {
732         nc->receive_disabled = 1;
733     }
734 
735     return ret;
736 }
737 
738 ssize_t qemu_sendv_packet_async(NetClientState *sender,
739                                 const struct iovec *iov, int iovcnt,
740                                 NetPacketSent *sent_cb)
741 {
742     NetQueue *queue;
743     size_t size = iov_size(iov, iovcnt);
744     int ret;
745 
746     if (size > NET_BUFSIZE) {
747         return size;
748     }
749 
750     if (sender->link_down || !sender->peer) {
751         return size;
752     }
753 
754     /* Let filters handle the packet first */
755     ret = filter_receive_iov(sender, NET_FILTER_DIRECTION_TX, sender,
756                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
757     if (ret) {
758         return ret;
759     }
760 
761     ret = filter_receive_iov(sender->peer, NET_FILTER_DIRECTION_RX, sender,
762                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
763     if (ret) {
764         return ret;
765     }
766 
767     queue = sender->peer->incoming_queue;
768 
769     return qemu_net_queue_send_iov(queue, sender,
770                                    QEMU_NET_PACKET_FLAG_NONE,
771                                    iov, iovcnt, sent_cb);
772 }
773 
774 ssize_t
775 qemu_sendv_packet(NetClientState *nc, const struct iovec *iov, int iovcnt)
776 {
777     return qemu_sendv_packet_async(nc, iov, iovcnt, NULL);
778 }
779 
780 NetClientState *qemu_find_netdev(const char *id)
781 {
782     NetClientState *nc;
783 
784     QTAILQ_FOREACH(nc, &net_clients, next) {
785         if (nc->info->type == NET_CLIENT_DRIVER_NIC)
786             continue;
787         if (!strcmp(nc->name, id)) {
788             return nc;
789         }
790     }
791 
792     return NULL;
793 }
794 
795 int qemu_find_net_clients_except(const char *id, NetClientState **ncs,
796                                  NetClientDriver type, int max)
797 {
798     NetClientState *nc;
799     int ret = 0;
800 
801     QTAILQ_FOREACH(nc, &net_clients, next) {
802         if (nc->info->type == type) {
803             continue;
804         }
805         if (!id || !strcmp(nc->name, id)) {
806             if (ret < max) {
807                 ncs[ret] = nc;
808             }
809             ret++;
810         }
811     }
812 
813     return ret;
814 }
815 
816 static int nic_get_free_idx(void)
817 {
818     int index;
819 
820     for (index = 0; index < MAX_NICS; index++)
821         if (!nd_table[index].used)
822             return index;
823     return -1;
824 }
825 
826 int qemu_show_nic_models(const char *arg, const char *const *models)
827 {
828     int i;
829 
830     if (!arg || !is_help_option(arg)) {
831         return 0;
832     }
833 
834     printf("Supported NIC models:\n");
835     for (i = 0 ; models[i]; i++) {
836         printf("%s\n", models[i]);
837     }
838     return 1;
839 }
840 
841 void qemu_check_nic_model(NICInfo *nd, const char *model)
842 {
843     const char *models[2];
844 
845     models[0] = model;
846     models[1] = NULL;
847 
848     if (qemu_show_nic_models(nd->model, models))
849         exit(0);
850     if (qemu_find_nic_model(nd, models, model) < 0)
851         exit(1);
852 }
853 
854 int qemu_find_nic_model(NICInfo *nd, const char * const *models,
855                         const char *default_model)
856 {
857     int i;
858 
859     if (!nd->model)
860         nd->model = g_strdup(default_model);
861 
862     for (i = 0 ; models[i]; i++) {
863         if (strcmp(nd->model, models[i]) == 0)
864             return i;
865     }
866 
867     error_report("Unsupported NIC model: %s", nd->model);
868     return -1;
869 }
870 
871 static int net_init_nic(const Netdev *netdev, const char *name,
872                         NetClientState *peer, Error **errp)
873 {
874     int idx;
875     NICInfo *nd;
876     const NetLegacyNicOptions *nic;
877 
878     assert(netdev->type == NET_CLIENT_DRIVER_NIC);
879     nic = &netdev->u.nic;
880 
881     idx = nic_get_free_idx();
882     if (idx == -1 || nb_nics >= MAX_NICS) {
883         error_setg(errp, "too many NICs");
884         return -1;
885     }
886 
887     nd = &nd_table[idx];
888 
889     memset(nd, 0, sizeof(*nd));
890 
891     if (nic->has_netdev) {
892         nd->netdev = qemu_find_netdev(nic->netdev);
893         if (!nd->netdev) {
894             error_setg(errp, "netdev '%s' not found", nic->netdev);
895             return -1;
896         }
897     } else {
898         assert(peer);
899         nd->netdev = peer;
900     }
901     nd->name = g_strdup(name);
902     if (nic->has_model) {
903         nd->model = g_strdup(nic->model);
904     }
905     if (nic->has_addr) {
906         nd->devaddr = g_strdup(nic->addr);
907     }
908 
909     if (nic->has_macaddr &&
910         net_parse_macaddr(nd->macaddr.a, nic->macaddr) < 0) {
911         error_setg(errp, "invalid syntax for ethernet address");
912         return -1;
913     }
914     if (nic->has_macaddr &&
915         is_multicast_ether_addr(nd->macaddr.a)) {
916         error_setg(errp,
917                    "NIC cannot have multicast MAC address (odd 1st byte)");
918         return -1;
919     }
920     qemu_macaddr_default_if_unset(&nd->macaddr);
921 
922     if (nic->has_vectors) {
923         if (nic->vectors > 0x7ffffff) {
924             error_setg(errp, "invalid # of vectors: %"PRIu32, nic->vectors);
925             return -1;
926         }
927         nd->nvectors = nic->vectors;
928     } else {
929         nd->nvectors = DEV_NVECTORS_UNSPECIFIED;
930     }
931 
932     nd->used = 1;
933     nb_nics++;
934 
935     return idx;
936 }
937 
938 
939 static int (* const net_client_init_fun[NET_CLIENT_DRIVER__MAX])(
940     const Netdev *netdev,
941     const char *name,
942     NetClientState *peer, Error **errp) = {
943         [NET_CLIENT_DRIVER_NIC]       = net_init_nic,
944 #ifdef CONFIG_SLIRP
945         [NET_CLIENT_DRIVER_USER]      = net_init_slirp,
946 #endif
947         [NET_CLIENT_DRIVER_TAP]       = net_init_tap,
948         [NET_CLIENT_DRIVER_SOCKET]    = net_init_socket,
949 #ifdef CONFIG_VDE
950         [NET_CLIENT_DRIVER_VDE]       = net_init_vde,
951 #endif
952 #ifdef CONFIG_NETMAP
953         [NET_CLIENT_DRIVER_NETMAP]    = net_init_netmap,
954 #endif
955 #ifdef CONFIG_NET_BRIDGE
956         [NET_CLIENT_DRIVER_BRIDGE]    = net_init_bridge,
957 #endif
958         [NET_CLIENT_DRIVER_HUBPORT]   = net_init_hubport,
959 #ifdef CONFIG_VHOST_NET_USER
960         [NET_CLIENT_DRIVER_VHOST_USER] = net_init_vhost_user,
961 #endif
962 #ifdef CONFIG_L2TPV3
963         [NET_CLIENT_DRIVER_L2TPV3]    = net_init_l2tpv3,
964 #endif
965 };
966 
967 
968 static int net_client_init1(const Netdev *netdev, bool is_netdev, Error **errp)
969 {
970     NetClientState *peer = NULL;
971 
972     if (is_netdev) {
973         if (netdev->type == NET_CLIENT_DRIVER_NIC ||
974             !net_client_init_fun[netdev->type]) {
975             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
976                        "a netdev backend type");
977             return -1;
978         }
979     } else {
980         if (netdev->type == NET_CLIENT_DRIVER_NONE) {
981             return 0; /* nothing to do */
982         }
983         if (netdev->type == NET_CLIENT_DRIVER_HUBPORT ||
984             !net_client_init_fun[netdev->type]) {
985             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
986                        "a net backend type (maybe it is not compiled "
987                        "into this binary)");
988             return -1;
989         }
990 
991         /* Do not add to a hub if it's a nic with a netdev= parameter. */
992         if (netdev->type != NET_CLIENT_DRIVER_NIC ||
993             !netdev->u.nic.has_netdev) {
994             peer = net_hub_add_port(0, NULL, NULL);
995         }
996     }
997 
998     if (net_client_init_fun[netdev->type](netdev, netdev->id, peer, errp) < 0) {
999         /* FIXME drop when all init functions store an Error */
1000         if (errp && !*errp) {
1001             error_setg(errp, QERR_DEVICE_INIT_FAILED,
1002                        NetClientDriver_str(netdev->type));
1003         }
1004         return -1;
1005     }
1006 
1007     if (is_netdev) {
1008         NetClientState *nc;
1009 
1010         nc = qemu_find_netdev(netdev->id);
1011         assert(nc);
1012         nc->is_netdev = true;
1013     }
1014 
1015     return 0;
1016 }
1017 
1018 static void show_netdevs(void)
1019 {
1020     int idx;
1021     const char *available_netdevs[] = {
1022         "socket",
1023         "hubport",
1024         "tap",
1025 #ifdef CONFIG_SLIRP
1026         "user",
1027 #endif
1028 #ifdef CONFIG_L2TPV3
1029         "l2tpv3",
1030 #endif
1031 #ifdef CONFIG_VDE
1032         "vde",
1033 #endif
1034 #ifdef CONFIG_NET_BRIDGE
1035         "bridge",
1036 #endif
1037 #ifdef CONFIG_NETMAP
1038         "netmap",
1039 #endif
1040 #ifdef CONFIG_POSIX
1041         "vhost-user",
1042 #endif
1043     };
1044 
1045     printf("Available netdev backend types:\n");
1046     for (idx = 0; idx < ARRAY_SIZE(available_netdevs); idx++) {
1047         puts(available_netdevs[idx]);
1048     }
1049 }
1050 
1051 static int net_client_init(QemuOpts *opts, bool is_netdev, Error **errp)
1052 {
1053     gchar **substrings = NULL;
1054     Netdev *object = NULL;
1055     Error *err = NULL;
1056     int ret = -1;
1057     Visitor *v = opts_visitor_new(opts);
1058 
1059     const char *type = qemu_opt_get(opts, "type");
1060 
1061     if (is_netdev && type && is_help_option(type)) {
1062         show_netdevs();
1063         exit(0);
1064     } else {
1065         /* Parse convenience option format ip6-net=fec0::0[/64] */
1066         const char *ip6_net = qemu_opt_get(opts, "ipv6-net");
1067 
1068         if (ip6_net) {
1069             char *prefix_addr;
1070             unsigned long prefix_len = 64; /* Default 64bit prefix length. */
1071 
1072             substrings = g_strsplit(ip6_net, "/", 2);
1073             if (!substrings || !substrings[0]) {
1074                 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "ipv6-net",
1075                            "a valid IPv6 prefix");
1076                 goto out;
1077             }
1078 
1079             prefix_addr = substrings[0];
1080 
1081             /* Handle user-specified prefix length. */
1082             if (substrings[1] &&
1083                 qemu_strtoul(substrings[1], NULL, 10, &prefix_len))
1084             {
1085                 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1086                            "ipv6-prefixlen", "a number");
1087                 goto out;
1088             }
1089 
1090             qemu_opt_set(opts, "ipv6-prefix", prefix_addr, &error_abort);
1091             qemu_opt_set_number(opts, "ipv6-prefixlen", prefix_len,
1092                                 &error_abort);
1093             qemu_opt_unset(opts, "ipv6-net");
1094         }
1095     }
1096 
1097     /* Create an ID for -net if the user did not specify one */
1098     if (!is_netdev && !qemu_opts_id(opts)) {
1099         static int idx;
1100         qemu_opts_set_id(opts, g_strdup_printf("__org.qemu.net%i", idx++));
1101     }
1102 
1103     visit_type_Netdev(v, NULL, &object, &err);
1104 
1105     if (!err) {
1106         ret = net_client_init1(object, is_netdev, &err);
1107     }
1108 
1109     qapi_free_Netdev(object);
1110 
1111 out:
1112     error_propagate(errp, err);
1113     g_strfreev(substrings);
1114     visit_free(v);
1115     return ret;
1116 }
1117 
1118 void netdev_add(QemuOpts *opts, Error **errp)
1119 {
1120     net_client_init(opts, true, errp);
1121 }
1122 
1123 void qmp_netdev_add(Netdev *netdev, Error **errp)
1124 {
1125     net_client_init1(netdev, true, errp);
1126 }
1127 
1128 void qmp_netdev_del(const char *id, Error **errp)
1129 {
1130     NetClientState *nc;
1131 
1132     nc = qemu_find_netdev(id);
1133     if (!nc) {
1134         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1135                   "Device '%s' not found", id);
1136         return;
1137     }
1138 
1139     if (!nc->is_netdev) {
1140         error_setg(errp, "Device '%s' is not a netdev", id);
1141         return;
1142     }
1143 
1144     qemu_del_net_client(nc);
1145 }
1146 
1147 static void netfilter_print_info(Monitor *mon, NetFilterState *nf)
1148 {
1149     char *str;
1150     ObjectProperty *prop;
1151     ObjectPropertyIterator iter;
1152     Visitor *v;
1153 
1154     /* generate info str */
1155     object_property_iter_init(&iter, OBJECT(nf));
1156     while ((prop = object_property_iter_next(&iter))) {
1157         if (!strcmp(prop->name, "type")) {
1158             continue;
1159         }
1160         v = string_output_visitor_new(false, &str);
1161         object_property_get(OBJECT(nf), v, prop->name, NULL);
1162         visit_complete(v, &str);
1163         visit_free(v);
1164         monitor_printf(mon, ",%s=%s", prop->name, str);
1165         g_free(str);
1166     }
1167     monitor_printf(mon, "\n");
1168 }
1169 
1170 void print_net_client(Monitor *mon, NetClientState *nc)
1171 {
1172     NetFilterState *nf;
1173 
1174     monitor_printf(mon, "%s: index=%d,type=%s,%s\n", nc->name,
1175                    nc->queue_index,
1176                    NetClientDriver_str(nc->info->type),
1177                    nc->info_str);
1178     if (!QTAILQ_EMPTY(&nc->filters)) {
1179         monitor_printf(mon, "filters:\n");
1180     }
1181     QTAILQ_FOREACH(nf, &nc->filters, next) {
1182         char *path = object_get_canonical_path_component(OBJECT(nf));
1183 
1184         monitor_printf(mon, "  - %s: type=%s", path,
1185                        object_get_typename(OBJECT(nf)));
1186         netfilter_print_info(mon, nf);
1187         g_free(path);
1188     }
1189 }
1190 
1191 RxFilterInfoList *qmp_query_rx_filter(bool has_name, const char *name,
1192                                       Error **errp)
1193 {
1194     NetClientState *nc;
1195     RxFilterInfoList *filter_list = NULL, *last_entry = NULL;
1196 
1197     QTAILQ_FOREACH(nc, &net_clients, next) {
1198         RxFilterInfoList *entry;
1199         RxFilterInfo *info;
1200 
1201         if (has_name && strcmp(nc->name, name) != 0) {
1202             continue;
1203         }
1204 
1205         /* only query rx-filter information of NIC */
1206         if (nc->info->type != NET_CLIENT_DRIVER_NIC) {
1207             if (has_name) {
1208                 error_setg(errp, "net client(%s) isn't a NIC", name);
1209                 return NULL;
1210             }
1211             continue;
1212         }
1213 
1214         /* only query information on queue 0 since the info is per nic,
1215          * not per queue
1216          */
1217         if (nc->queue_index != 0)
1218             continue;
1219 
1220         if (nc->info->query_rx_filter) {
1221             info = nc->info->query_rx_filter(nc);
1222             entry = g_malloc0(sizeof(*entry));
1223             entry->value = info;
1224 
1225             if (!filter_list) {
1226                 filter_list = entry;
1227             } else {
1228                 last_entry->next = entry;
1229             }
1230             last_entry = entry;
1231         } else if (has_name) {
1232             error_setg(errp, "net client(%s) doesn't support"
1233                        " rx-filter querying", name);
1234             return NULL;
1235         }
1236 
1237         if (has_name) {
1238             break;
1239         }
1240     }
1241 
1242     if (filter_list == NULL && has_name) {
1243         error_setg(errp, "invalid net client name: %s", name);
1244     }
1245 
1246     return filter_list;
1247 }
1248 
1249 void hmp_info_network(Monitor *mon, const QDict *qdict)
1250 {
1251     NetClientState *nc, *peer;
1252     NetClientDriver type;
1253 
1254     net_hub_info(mon);
1255 
1256     QTAILQ_FOREACH(nc, &net_clients, next) {
1257         peer = nc->peer;
1258         type = nc->info->type;
1259 
1260         /* Skip if already printed in hub info */
1261         if (net_hub_id_for_client(nc, NULL) == 0) {
1262             continue;
1263         }
1264 
1265         if (!peer || type == NET_CLIENT_DRIVER_NIC) {
1266             print_net_client(mon, nc);
1267         } /* else it's a netdev connected to a NIC, printed with the NIC */
1268         if (peer && type == NET_CLIENT_DRIVER_NIC) {
1269             monitor_printf(mon, " \\ ");
1270             print_net_client(mon, peer);
1271         }
1272     }
1273 }
1274 
1275 void colo_notify_filters_event(int event, Error **errp)
1276 {
1277     NetClientState *nc;
1278     NetFilterState *nf;
1279     NetFilterClass *nfc = NULL;
1280     Error *local_err = NULL;
1281 
1282     QTAILQ_FOREACH(nc, &net_clients, next) {
1283         QTAILQ_FOREACH(nf, &nc->filters, next) {
1284             nfc = NETFILTER_GET_CLASS(OBJECT(nf));
1285             nfc->handle_event(nf, event, &local_err);
1286             if (local_err) {
1287                 error_propagate(errp, local_err);
1288                 return;
1289             }
1290         }
1291     }
1292 }
1293 
1294 void qmp_set_link(const char *name, bool up, Error **errp)
1295 {
1296     NetClientState *ncs[MAX_QUEUE_NUM];
1297     NetClientState *nc;
1298     int queues, i;
1299 
1300     queues = qemu_find_net_clients_except(name, ncs,
1301                                           NET_CLIENT_DRIVER__MAX,
1302                                           MAX_QUEUE_NUM);
1303 
1304     if (queues == 0) {
1305         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1306                   "Device '%s' not found", name);
1307         return;
1308     }
1309     nc = ncs[0];
1310 
1311     for (i = 0; i < queues; i++) {
1312         ncs[i]->link_down = !up;
1313     }
1314 
1315     if (nc->info->link_status_changed) {
1316         nc->info->link_status_changed(nc);
1317     }
1318 
1319     if (nc->peer) {
1320         /* Change peer link only if the peer is NIC and then notify peer.
1321          * If the peer is a HUBPORT or a backend, we do not change the
1322          * link status.
1323          *
1324          * This behavior is compatible with qemu hubs where there could be
1325          * multiple clients that can still communicate with each other in
1326          * disconnected mode. For now maintain this compatibility.
1327          */
1328         if (nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
1329             for (i = 0; i < queues; i++) {
1330                 ncs[i]->peer->link_down = !up;
1331             }
1332         }
1333         if (nc->peer->info->link_status_changed) {
1334             nc->peer->info->link_status_changed(nc->peer);
1335         }
1336     }
1337 }
1338 
1339 static void net_vm_change_state_handler(void *opaque, int running,
1340                                         RunState state)
1341 {
1342     NetClientState *nc;
1343     NetClientState *tmp;
1344 
1345     QTAILQ_FOREACH_SAFE(nc, &net_clients, next, tmp) {
1346         if (running) {
1347             /* Flush queued packets and wake up backends. */
1348             if (nc->peer && qemu_can_send_packet(nc)) {
1349                 qemu_flush_queued_packets(nc->peer);
1350             }
1351         } else {
1352             /* Complete all queued packets, to guarantee we don't modify
1353              * state later when VM is not running.
1354              */
1355             qemu_flush_or_purge_queued_packets(nc, true);
1356         }
1357     }
1358 }
1359 
1360 void net_cleanup(void)
1361 {
1362     NetClientState *nc;
1363 
1364     /* We may del multiple entries during qemu_del_net_client(),
1365      * so QTAILQ_FOREACH_SAFE() is also not safe here.
1366      */
1367     while (!QTAILQ_EMPTY(&net_clients)) {
1368         nc = QTAILQ_FIRST(&net_clients);
1369         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
1370             qemu_del_nic(qemu_get_nic(nc));
1371         } else {
1372             qemu_del_net_client(nc);
1373         }
1374     }
1375 
1376     qemu_del_vm_change_state_handler(net_change_state_entry);
1377 }
1378 
1379 void net_check_clients(void)
1380 {
1381     NetClientState *nc;
1382     int i;
1383 
1384     net_hub_check_clients();
1385 
1386     QTAILQ_FOREACH(nc, &net_clients, next) {
1387         if (!nc->peer) {
1388             warn_report("%s %s has no peer",
1389                         nc->info->type == NET_CLIENT_DRIVER_NIC
1390                         ? "nic" : "netdev",
1391                         nc->name);
1392         }
1393     }
1394 
1395     /* Check that all NICs requested via -net nic actually got created.
1396      * NICs created via -device don't need to be checked here because
1397      * they are always instantiated.
1398      */
1399     for (i = 0; i < MAX_NICS; i++) {
1400         NICInfo *nd = &nd_table[i];
1401         if (nd->used && !nd->instantiated) {
1402             warn_report("requested NIC (%s, model %s) "
1403                         "was not created (not supported by this machine?)",
1404                         nd->name ? nd->name : "anonymous",
1405                         nd->model ? nd->model : "unspecified");
1406         }
1407     }
1408 }
1409 
1410 static int net_init_client(void *dummy, QemuOpts *opts, Error **errp)
1411 {
1412     return net_client_init(opts, false, errp);
1413 }
1414 
1415 static int net_init_netdev(void *dummy, QemuOpts *opts, Error **errp)
1416 {
1417     return net_client_init(opts, true, errp);
1418 }
1419 
1420 /* For the convenience "--nic" parameter */
1421 static int net_param_nic(void *dummy, QemuOpts *opts, Error **errp)
1422 {
1423     char *mac, *nd_id;
1424     int idx, ret;
1425     NICInfo *ni;
1426     const char *type;
1427 
1428     type = qemu_opt_get(opts, "type");
1429     if (type && g_str_equal(type, "none")) {
1430         return 0;    /* Nothing to do, default_net is cleared in vl.c */
1431     }
1432 
1433     idx = nic_get_free_idx();
1434     if (idx == -1 || nb_nics >= MAX_NICS) {
1435         error_setg(errp, "no more on-board/default NIC slots available");
1436         return -1;
1437     }
1438 
1439     if (!type) {
1440         qemu_opt_set(opts, "type", "user", &error_abort);
1441     }
1442 
1443     ni = &nd_table[idx];
1444     memset(ni, 0, sizeof(*ni));
1445     ni->model = qemu_opt_get_del(opts, "model");
1446 
1447     /* Create an ID if the user did not specify one */
1448     nd_id = g_strdup(qemu_opts_id(opts));
1449     if (!nd_id) {
1450         nd_id = g_strdup_printf("__org.qemu.nic%i", idx);
1451         qemu_opts_set_id(opts, nd_id);
1452     }
1453 
1454     /* Handle MAC address */
1455     mac = qemu_opt_get_del(opts, "mac");
1456     if (mac) {
1457         ret = net_parse_macaddr(ni->macaddr.a, mac);
1458         g_free(mac);
1459         if (ret) {
1460             error_setg(errp, "invalid syntax for ethernet address");
1461             goto out;
1462         }
1463         if (is_multicast_ether_addr(ni->macaddr.a)) {
1464             error_setg(errp, "NIC cannot have multicast MAC address");
1465             ret = -1;
1466             goto out;
1467         }
1468     }
1469     qemu_macaddr_default_if_unset(&ni->macaddr);
1470 
1471     ret = net_client_init(opts, true, errp);
1472     if (ret == 0) {
1473         ni->netdev = qemu_find_netdev(nd_id);
1474         ni->used = true;
1475         nb_nics++;
1476     }
1477 
1478 out:
1479     g_free(nd_id);
1480     return ret;
1481 }
1482 
1483 int net_init_clients(Error **errp)
1484 {
1485     net_change_state_entry =
1486         qemu_add_vm_change_state_handler(net_vm_change_state_handler, NULL);
1487 
1488     QTAILQ_INIT(&net_clients);
1489 
1490     if (qemu_opts_foreach(qemu_find_opts("netdev"),
1491                           net_init_netdev, NULL, errp)) {
1492         return -1;
1493     }
1494 
1495     if (qemu_opts_foreach(qemu_find_opts("nic"), net_param_nic, NULL, errp)) {
1496         return -1;
1497     }
1498 
1499     if (qemu_opts_foreach(qemu_find_opts("net"), net_init_client, NULL, errp)) {
1500         return -1;
1501     }
1502 
1503     return 0;
1504 }
1505 
1506 int net_client_parse(QemuOptsList *opts_list, const char *optarg)
1507 {
1508     if (!qemu_opts_parse_noisily(opts_list, optarg, true)) {
1509         return -1;
1510     }
1511 
1512     return 0;
1513 }
1514 
1515 /* From FreeBSD */
1516 /* XXX: optimize */
1517 uint32_t net_crc32(const uint8_t *p, int len)
1518 {
1519     uint32_t crc;
1520     int carry, i, j;
1521     uint8_t b;
1522 
1523     crc = 0xffffffff;
1524     for (i = 0; i < len; i++) {
1525         b = *p++;
1526         for (j = 0; j < 8; j++) {
1527             carry = ((crc & 0x80000000L) ? 1 : 0) ^ (b & 0x01);
1528             crc <<= 1;
1529             b >>= 1;
1530             if (carry) {
1531                 crc = ((crc ^ POLYNOMIAL_BE) | carry);
1532             }
1533         }
1534     }
1535 
1536     return crc;
1537 }
1538 
1539 uint32_t net_crc32_le(const uint8_t *p, int len)
1540 {
1541     uint32_t crc;
1542     int carry, i, j;
1543     uint8_t b;
1544 
1545     crc = 0xffffffff;
1546     for (i = 0; i < len; i++) {
1547         b = *p++;
1548         for (j = 0; j < 8; j++) {
1549             carry = (crc & 0x1) ^ (b & 0x01);
1550             crc >>= 1;
1551             b >>= 1;
1552             if (carry) {
1553                 crc ^= POLYNOMIAL_LE;
1554             }
1555         }
1556     }
1557 
1558     return crc;
1559 }
1560 
1561 QemuOptsList qemu_netdev_opts = {
1562     .name = "netdev",
1563     .implied_opt_name = "type",
1564     .head = QTAILQ_HEAD_INITIALIZER(qemu_netdev_opts.head),
1565     .desc = {
1566         /*
1567          * no elements => accept any params
1568          * validation will happen later
1569          */
1570         { /* end of list */ }
1571     },
1572 };
1573 
1574 QemuOptsList qemu_nic_opts = {
1575     .name = "nic",
1576     .implied_opt_name = "type",
1577     .head = QTAILQ_HEAD_INITIALIZER(qemu_nic_opts.head),
1578     .desc = {
1579         /*
1580          * no elements => accept any params
1581          * validation will happen later
1582          */
1583         { /* end of list */ }
1584     },
1585 };
1586 
1587 QemuOptsList qemu_net_opts = {
1588     .name = "net",
1589     .implied_opt_name = "type",
1590     .head = QTAILQ_HEAD_INITIALIZER(qemu_net_opts.head),
1591     .desc = {
1592         /*
1593          * no elements => accept any params
1594          * validation will happen later
1595          */
1596         { /* end of list */ }
1597     },
1598 };
1599 
1600 void net_socket_rs_init(SocketReadState *rs,
1601                         SocketReadStateFinalize *finalize,
1602                         bool vnet_hdr)
1603 {
1604     rs->state = 0;
1605     rs->vnet_hdr = vnet_hdr;
1606     rs->index = 0;
1607     rs->packet_len = 0;
1608     rs->vnet_hdr_len = 0;
1609     memset(rs->buf, 0, sizeof(rs->buf));
1610     rs->finalize = finalize;
1611 }
1612 
1613 /*
1614  * Returns
1615  * 0: success
1616  * -1: error occurs
1617  */
1618 int net_fill_rstate(SocketReadState *rs, const uint8_t *buf, int size)
1619 {
1620     unsigned int l;
1621 
1622     while (size > 0) {
1623         /* Reassemble a packet from the network.
1624          * 0 = getting length.
1625          * 1 = getting vnet header length.
1626          * 2 = getting data.
1627          */
1628         switch (rs->state) {
1629         case 0:
1630             l = 4 - rs->index;
1631             if (l > size) {
1632                 l = size;
1633             }
1634             memcpy(rs->buf + rs->index, buf, l);
1635             buf += l;
1636             size -= l;
1637             rs->index += l;
1638             if (rs->index == 4) {
1639                 /* got length */
1640                 rs->packet_len = ntohl(*(uint32_t *)rs->buf);
1641                 rs->index = 0;
1642                 if (rs->vnet_hdr) {
1643                     rs->state = 1;
1644                 } else {
1645                     rs->state = 2;
1646                     rs->vnet_hdr_len = 0;
1647                 }
1648             }
1649             break;
1650         case 1:
1651             l = 4 - rs->index;
1652             if (l > size) {
1653                 l = size;
1654             }
1655             memcpy(rs->buf + rs->index, buf, l);
1656             buf += l;
1657             size -= l;
1658             rs->index += l;
1659             if (rs->index == 4) {
1660                 /* got vnet header length */
1661                 rs->vnet_hdr_len = ntohl(*(uint32_t *)rs->buf);
1662                 rs->index = 0;
1663                 rs->state = 2;
1664             }
1665             break;
1666         case 2:
1667             l = rs->packet_len - rs->index;
1668             if (l > size) {
1669                 l = size;
1670             }
1671             if (rs->index + l <= sizeof(rs->buf)) {
1672                 memcpy(rs->buf + rs->index, buf, l);
1673             } else {
1674                 fprintf(stderr, "serious error: oversized packet received,"
1675                     "connection terminated.\n");
1676                 rs->index = rs->state = 0;
1677                 return -1;
1678             }
1679 
1680             rs->index += l;
1681             buf += l;
1682             size -= l;
1683             if (rs->index >= rs->packet_len) {
1684                 rs->index = 0;
1685                 rs->state = 0;
1686                 assert(rs->finalize);
1687                 rs->finalize(rs);
1688             }
1689             break;
1690         }
1691     }
1692 
1693     assert(size == 0);
1694     return 0;
1695 }
1696