net/net.c

   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 "qemu/osdep.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 "qapi/qmp/qerror.h"
  36 #include "qemu/error-report.h"
  37 #include "qemu/sockets.h"
  38 #include "qemu/config-file.h"
  39 #include "qmp-commands.h"
  40 #include "hw/qdev.h"
  41 #include "qemu/iov.h"
  42 #include "qemu/main-loop.h"
  43 #include "qapi-visit.h"
  44 #include "qapi/opts-visitor.h"
  45 #include "sysemu/sysemu.h"
  46 #include "net/filter.h"
  47 #include "qapi/string-output-visitor.h"
  48
  49 /* Net bridge is currently not supported for W32. */
  50 #if !defined(_WIN32)
  51 # define CONFIG_NET_BRIDGE
  52 #endif
  53
  54 static VMChangeStateEntry *net_change_state_entry;
  55 static QTAILQ_HEAD(, NetClientState) net_clients;
  56
  57 const char *host_net_devices[] = {
  58     "tap",
  59     "socket",
  60     "dump",
  61 #ifdef CONFIG_NET_BRIDGE
  62     "bridge",
  63 #endif
  64 #ifdef CONFIG_NETMAP
  65     "netmap",
  66 #endif
  67 #ifdef CONFIG_SLIRP
  68     "user",
  69 #endif
  70 #ifdef CONFIG_VDE
  71     "vde",
  72 #endif
  73     "vhost-user",
  74     NULL,
  75 };
  76
  77 int default_net = 1;
  78
  79 /***********************************************************/
  80 /* network device redirectors */
  81
  82 #if defined(DEBUG_NET)
  83 static void hex_dump(FILE *f, const uint8_t *buf, int size)
  84 {
  85     int len, i, j, c;
  86
  87     for(i=0;i<size;i+=16) {
  88         len = size - i;
  89         if (len > 16)
  90             len = 16;
  91         fprintf(f, "%08x ", i);
  92         for(j=0;j<16;j++) {
  93             if (j < len)
  94                 fprintf(f, " %02x", buf[i+j]);
  95             else
  96                 fprintf(f, "   ");
  97         }
  98         fprintf(f, " ");
  99         for(j=0;j<len;j++) {
 100             c = buf[i+j];
 101             if (c < ' ' || c > '~')
 102                 c = '.';
 103             fprintf(f, "%c", c);
 104         }
 105         fprintf(f, "\n");
 106     }
 107 }
 108 #endif
 109
 110 static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
 111 {
 112     const char *p, *p1;
 113     int len;
 114     p = *pp;
 115     p1 = strchr(p, sep);
 116     if (!p1)
 117         return -1;
 118     len = p1 - p;
 119     p1++;
 120     if (buf_size > 0) {
 121         if (len > buf_size - 1)
 122             len = buf_size - 1;
 123         memcpy(buf, p, len);
 124         buf[len] = '\0';
 125     }
 126     *pp = p1;
 127     return 0;
 128 }
 129
 130 int parse_host_port(struct sockaddr_in *saddr, const char *str)
 131 {
 132     char buf[512];
 133     struct hostent *he;
 134     const char *p, *r;
 135     int port;
 136
 137     p = str;
 138     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0)
 139         return -1;
 140     saddr->sin_family = AF_INET;
 141     if (buf[0] == '\0') {
 142         saddr->sin_addr.s_addr = 0;
 143     } else {
 144         if (qemu_isdigit(buf[0])) {
 145             if (!inet_aton(buf, &saddr->sin_addr))
 146                 return -1;
 147         } else {
 148             if ((he = gethostbyname(buf)) == NULL)
 149                 return - 1;
 150             saddr->sin_addr = *(struct in_addr *)he->h_addr;
 151         }
 152     }
 153     port = strtol(p, (char **)&r, 0);
 154     if (r == p)
 155         return -1;
 156     saddr->sin_port = htons(port);
 157     return 0;
 158 }
 159
 160 char *qemu_mac_strdup_printf(const uint8_t *macaddr)
 161 {
 162     return g_strdup_printf("%.2x:%.2x:%.2x:%.2x:%.2x:%.2x",
 163                            macaddr[0], macaddr[1], macaddr[2],
 164                            macaddr[3], macaddr[4], macaddr[5]);
 165 }
 166
 167 void qemu_format_nic_info_str(NetClientState *nc, uint8_t macaddr[6])
 168 {
 169     snprintf(nc->info_str, sizeof(nc->info_str),
 170              "model=%s,macaddr=%02x:%02x:%02x:%02x:%02x:%02x",
 171              nc->model,
 172              macaddr[0], macaddr[1], macaddr[2],
 173              macaddr[3], macaddr[4], macaddr[5]);
 174 }
 175
 176 static int mac_table[256] = {0};
 177
 178 static void qemu_macaddr_set_used(MACAddr *macaddr)
 179 {
 180     int index;
 181
 182     for (index = 0x56; index < 0xFF; index++) {
 183         if (macaddr->a[5] == index) {
 184             mac_table[index]++;
 185         }
 186     }
 187 }
 188
 189 static void qemu_macaddr_set_free(MACAddr *macaddr)
 190 {
 191     int index;
 192     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
 193
 194     if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
 195         return;
 196     }
 197     for (index = 0x56; index < 0xFF; index++) {
 198         if (macaddr->a[5] == index) {
 199             mac_table[index]--;
 200         }
 201     }
 202 }
 203
 204 static int qemu_macaddr_get_free(void)
 205 {
 206     int index;
 207
 208     for (index = 0x56; index < 0xFF; index++) {
 209         if (mac_table[index] == 0) {
 210             return index;
 211         }
 212     }
 213
 214     return -1;
 215 }
 216
 217 void qemu_macaddr_default_if_unset(MACAddr *macaddr)
 218 {
 219     static const MACAddr zero = { .a = { 0,0,0,0,0,0 } };
 220     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
 221
 222     if (memcmp(macaddr, &zero, sizeof(zero)) != 0) {
 223         if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
 224             return;
 225         } else {
 226             qemu_macaddr_set_used(macaddr);
 227             return;
 228         }
 229     }
 230
 231     macaddr->a[0] = 0x52;
 232     macaddr->a[1] = 0x54;
 233     macaddr->a[2] = 0x00;
 234     macaddr->a[3] = 0x12;
 235     macaddr->a[4] = 0x34;
 236     macaddr->a[5] = qemu_macaddr_get_free();
 237     qemu_macaddr_set_used(macaddr);
 238 }
 239
 240 /**
 241  * Generate a name for net client
 242  *
 243  * Only net clients created with the legacy -net option and NICs need this.
 244  */
 245 static char *assign_name(NetClientState *nc1, const char *model)
 246 {
 247     NetClientState *nc;
 248     int id = 0;
 249
 250     QTAILQ_FOREACH(nc, &net_clients, next) {
 251         if (nc == nc1) {
 252             continue;
 253         }
 254         if (strcmp(nc->model, model) == 0) {
 255             id++;
 256         }
 257     }
 258
 259     return g_strdup_printf("%s.%d", model, id);
 260 }
 261
 262 static void qemu_net_client_destructor(NetClientState *nc)
 263 {
 264     g_free(nc);
 265 }
 266
 267 static void qemu_net_client_setup(NetClientState *nc,
 268                                   NetClientInfo *info,
 269                                   NetClientState *peer,
 270                                   const char *model,
 271                                   const char *name,
 272                                   NetClientDestructor *destructor)
 273 {
 274     nc->info = info;
 275     nc->model = g_strdup(model);
 276     if (name) {
 277         nc->name = g_strdup(name);
 278     } else {
 279         nc->name = assign_name(nc, model);
 280     }
 281
 282     if (peer) {
 283         assert(!peer->peer);
 284         nc->peer = peer;
 285         peer->peer = nc;
 286     }
 287     QTAILQ_INSERT_TAIL(&net_clients, nc, next);
 288
 289     nc->incoming_queue = qemu_new_net_queue(qemu_deliver_packet_iov, nc);
 290     nc->destructor = destructor;
 291     QTAILQ_INIT(&nc->filters);
 292 }
 293
 294 NetClientState *qemu_new_net_client(NetClientInfo *info,
 295                                     NetClientState *peer,
 296                                     const char *model,
 297                                     const char *name)
 298 {
 299     NetClientState *nc;
 300
 301     assert(info->size >= sizeof(NetClientState));
 302
 303     nc = g_malloc0(info->size);
 304     qemu_net_client_setup(nc, info, peer, model, name,
 305                           qemu_net_client_destructor);
 306
 307     return nc;
 308 }
 309
 310 NICState *qemu_new_nic(NetClientInfo *info,
 311                        NICConf *conf,
 312                        const char *model,
 313                        const char *name,
 314                        void *opaque)
 315 {
 316     NetClientState **peers = conf->peers.ncs;
 317     NICState *nic;
 318     int i, queues = MAX(1, conf->peers.queues);
 319
 320     assert(info->type == NET_CLIENT_OPTIONS_KIND_NIC);
 321     assert(info->size >= sizeof(NICState));
 322
 323     nic = g_malloc0(info->size + sizeof(NetClientState) * queues);
 324     nic->ncs = (void *)nic + info->size;
 325     nic->conf = conf;
 326     nic->opaque = opaque;
 327
 328     for (i = 0; i < queues; i++) {
 329         qemu_net_client_setup(&nic->ncs[i], info, peers[i], model, name,
 330                               NULL);
 331         nic->ncs[i].queue_index = i;
 332     }
 333
 334     return nic;
 335 }
 336
 337 NetClientState *qemu_get_subqueue(NICState *nic, int queue_index)
 338 {
 339     return nic->ncs + queue_index;
 340 }
 341
 342 NetClientState *qemu_get_queue(NICState *nic)
 343 {
 344     return qemu_get_subqueue(nic, 0);
 345 }
 346
 347 NICState *qemu_get_nic(NetClientState *nc)
 348 {
 349     NetClientState *nc0 = nc - nc->queue_index;
 350
 351     return (NICState *)((void *)nc0 - nc->info->size);
 352 }
 353
 354 void *qemu_get_nic_opaque(NetClientState *nc)
 355 {
 356     NICState *nic = qemu_get_nic(nc);
 357
 358     return nic->opaque;
 359 }
 360
 361 static void qemu_cleanup_net_client(NetClientState *nc)
 362 {
 363     QTAILQ_REMOVE(&net_clients, nc, next);
 364
 365     if (nc->info->cleanup) {
 366         nc->info->cleanup(nc);
 367     }
 368 }
 369
 370 static void qemu_free_net_client(NetClientState *nc)
 371 {
 372     if (nc->incoming_queue) {
 373         qemu_del_net_queue(nc->incoming_queue);
 374     }
 375     if (nc->peer) {
 376         nc->peer->peer = NULL;
 377     }
 378     g_free(nc->name);
 379     g_free(nc->model);
 380     if (nc->destructor) {
 381         nc->destructor(nc);
 382     }
 383 }
 384
 385 void qemu_del_net_client(NetClientState *nc)
 386 {
 387     NetClientState *ncs[MAX_QUEUE_NUM];
 388     int queues, i;
 389     NetFilterState *nf, *next;
 390
 391     assert(nc->info->type != NET_CLIENT_OPTIONS_KIND_NIC);
 392
 393     /* If the NetClientState belongs to a multiqueue backend, we will change all
 394      * other NetClientStates also.
 395      */
 396     queues = qemu_find_net_clients_except(nc->name, ncs,
 397                                           NET_CLIENT_OPTIONS_KIND_NIC,
 398                                           MAX_QUEUE_NUM);
 399     assert(queues != 0);
 400
 401     QTAILQ_FOREACH_SAFE(nf, &nc->filters, next, next) {
 402         object_unparent(OBJECT(nf));
 403     }
 404
 405     /* If there is a peer NIC, delete and cleanup client, but do not free. */
 406     if (nc->peer && nc->peer->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
 407         NICState *nic = qemu_get_nic(nc->peer);
 408         if (nic->peer_deleted) {
 409             return;
 410         }
 411         nic->peer_deleted = true;
 412
 413         for (i = 0; i < queues; i++) {
 414             ncs[i]->peer->link_down = true;
 415         }
 416
 417         if (nc->peer->info->link_status_changed) {
 418             nc->peer->info->link_status_changed(nc->peer);
 419         }
 420
 421         for (i = 0; i < queues; i++) {
 422             qemu_cleanup_net_client(ncs[i]);
 423         }
 424
 425         return;
 426     }
 427
 428     for (i = 0; i < queues; i++) {
 429         qemu_cleanup_net_client(ncs[i]);
 430         qemu_free_net_client(ncs[i]);
 431     }
 432 }
 433
 434 void qemu_del_nic(NICState *nic)
 435 {
 436     int i, queues = MAX(nic->conf->peers.queues, 1);
 437
 438     qemu_macaddr_set_free(&nic->conf->macaddr);
 439
 440     /* If this is a peer NIC and peer has already been deleted, free it now. */
 441     if (nic->peer_deleted) {
 442         for (i = 0; i < queues; i++) {
 443             qemu_free_net_client(qemu_get_subqueue(nic, i)->peer);
 444         }
 445     }
 446
 447     for (i = queues - 1; i >= 0; i--) {
 448         NetClientState *nc = qemu_get_subqueue(nic, i);
 449
 450         qemu_cleanup_net_client(nc);
 451         qemu_free_net_client(nc);
 452     }
 453
 454     g_free(nic);
 455 }
 456
 457 void qemu_foreach_nic(qemu_nic_foreach func, void *opaque)
 458 {
 459     NetClientState *nc;
 460
 461     QTAILQ_FOREACH(nc, &net_clients, next) {
 462         if (nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
 463             if (nc->queue_index == 0) {
 464                 func(qemu_get_nic(nc), opaque);
 465             }
 466         }
 467     }
 468 }
 469
 470 bool qemu_has_ufo(NetClientState *nc)
 471 {
 472     if (!nc || !nc->info->has_ufo) {
 473         return false;
 474     }
 475
 476     return nc->info->has_ufo(nc);
 477 }
 478
 479 bool qemu_has_vnet_hdr(NetClientState *nc)
 480 {
 481     if (!nc || !nc->info->has_vnet_hdr) {
 482         return false;
 483     }
 484
 485     return nc->info->has_vnet_hdr(nc);
 486 }
 487
 488 bool qemu_has_vnet_hdr_len(NetClientState *nc, int len)
 489 {
 490     if (!nc || !nc->info->has_vnet_hdr_len) {
 491         return false;
 492     }
 493
 494     return nc->info->has_vnet_hdr_len(nc, len);
 495 }
 496
 497 void qemu_using_vnet_hdr(NetClientState *nc, bool enable)
 498 {
 499     if (!nc || !nc->info->using_vnet_hdr) {
 500         return;
 501     }
 502
 503     nc->info->using_vnet_hdr(nc, enable);
 504 }
 505
 506 void qemu_set_offload(NetClientState *nc, int csum, int tso4, int tso6,
 507                           int ecn, int ufo)
 508 {
 509     if (!nc || !nc->info->set_offload) {
 510         return;
 511     }
 512
 513     nc->info->set_offload(nc, csum, tso4, tso6, ecn, ufo);
 514 }
 515
 516 void qemu_set_vnet_hdr_len(NetClientState *nc, int len)
 517 {
 518     if (!nc || !nc->info->set_vnet_hdr_len) {
 519         return;
 520     }
 521
 522     nc->info->set_vnet_hdr_len(nc, len);
 523 }
 524
 525 int qemu_set_vnet_le(NetClientState *nc, bool is_le)
 526 {
 527 #ifdef HOST_WORDS_BIGENDIAN
 528     if (!nc || !nc->info->set_vnet_le) {
 529         return -ENOSYS;
 530     }
 531
 532     return nc->info->set_vnet_le(nc, is_le);
 533 #else
 534     return 0;
 535 #endif
 536 }
 537
 538 int qemu_set_vnet_be(NetClientState *nc, bool is_be)
 539 {
 540 #ifdef HOST_WORDS_BIGENDIAN
 541     return 0;
 542 #else
 543     if (!nc || !nc->info->set_vnet_be) {
 544         return -ENOSYS;
 545     }
 546
 547     return nc->info->set_vnet_be(nc, is_be);
 548 #endif
 549 }
 550
 551 int qemu_can_send_packet(NetClientState *sender)
 552 {
 553     int vm_running = runstate_is_running();
 554
 555     if (!vm_running) {
 556         return 0;
 557     }
 558
 559     if (!sender->peer) {
 560         return 1;
 561     }
 562
 563     if (sender->peer->receive_disabled) {
 564         return 0;
 565     } else if (sender->peer->info->can_receive &&
 566                !sender->peer->info->can_receive(sender->peer)) {
 567         return 0;
 568     }
 569     return 1;
 570 }
 571
 572 static ssize_t filter_receive_iov(NetClientState *nc,
 573                                   NetFilterDirection direction,
 574                                   NetClientState *sender,
 575                                   unsigned flags,
 576                                   const struct iovec *iov,
 577                                   int iovcnt,
 578                                   NetPacketSent *sent_cb)
 579 {
 580     ssize_t ret = 0;
 581     NetFilterState *nf = NULL;
 582
 583     if (direction == NET_FILTER_DIRECTION_TX) {
 584         QTAILQ_FOREACH(nf, &nc->filters, next) {
 585             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
 586                                          iovcnt, sent_cb);
 587             if (ret) {
 588                 return ret;
 589             }
 590         }
 591     } else {
 592         QTAILQ_FOREACH_REVERSE(nf, &nc->filters, NetFilterHead, next) {
 593             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
 594                                          iovcnt, sent_cb);
 595             if (ret) {
 596                 return ret;
 597             }
 598         }
 599     }
 600
 601     return ret;
 602 }
 603
 604 static ssize_t filter_receive(NetClientState *nc,
 605                               NetFilterDirection direction,
 606                               NetClientState *sender,
 607                               unsigned flags,
 608                               const uint8_t *data,
 609                               size_t size,
 610                               NetPacketSent *sent_cb)
 611 {
 612     struct iovec iov = {
 613         .iov_base = (void *)data,
 614         .iov_len = size
 615     };
 616
 617     return filter_receive_iov(nc, direction, sender, flags, &iov, 1, sent_cb);
 618 }
 619
 620 void qemu_purge_queued_packets(NetClientState *nc)
 621 {
 622     if (!nc->peer) {
 623         return;
 624     }
 625
 626     qemu_net_queue_purge(nc->peer->incoming_queue, nc);
 627 }
 628
 629 static
 630 void qemu_flush_or_purge_queued_packets(NetClientState *nc, bool purge)
 631 {
 632     nc->receive_disabled = 0;
 633
 634     if (nc->peer && nc->peer->info->type == NET_CLIENT_OPTIONS_KIND_HUBPORT) {
 635         if (net_hub_flush(nc->peer)) {
 636             qemu_notify_event();
 637         }
 638     }
 639     if (qemu_net_queue_flush(nc->incoming_queue)) {
 640         /* We emptied the queue successfully, signal to the IO thread to repoll
 641          * the file descriptor (for tap, for example).
 642          */
 643         qemu_notify_event();
 644     } else if (purge) {
 645         /* Unable to empty the queue, purge remaining packets */
 646         qemu_net_queue_purge(nc->incoming_queue, nc);
 647     }
 648 }
 649
 650 void qemu_flush_queued_packets(NetClientState *nc)
 651 {
 652     qemu_flush_or_purge_queued_packets(nc, false);
 653 }
 654
 655 static ssize_t qemu_send_packet_async_with_flags(NetClientState *sender,
 656                                                  unsigned flags,
 657                                                  const uint8_t *buf, int size,
 658                                                  NetPacketSent *sent_cb)
 659 {
 660     NetQueue *queue;
 661     int ret;
 662
 663 #ifdef DEBUG_NET
 664     printf("qemu_send_packet_async:\n");
 665     hex_dump(stdout, buf, size);
 666 #endif
 667
 668     if (sender->link_down || !sender->peer) {
 669         return size;
 670     }
 671
 672     /* Let filters handle the packet first */
 673     ret = filter_receive(sender, NET_FILTER_DIRECTION_TX,
 674                          sender, flags, buf, size, sent_cb);
 675     if (ret) {
 676         return ret;
 677     }
 678
 679     ret = filter_receive(sender->peer, NET_FILTER_DIRECTION_RX,
 680                          sender, flags, buf, size, sent_cb);
 681     if (ret) {
 682         return ret;
 683     }
 684
 685     queue = sender->peer->incoming_queue;
 686
 687     return qemu_net_queue_send(queue, sender, flags, buf, size, sent_cb);
 688 }
 689
 690 ssize_t qemu_send_packet_async(NetClientState *sender,
 691                                const uint8_t *buf, int size,
 692                                NetPacketSent *sent_cb)
 693 {
 694     return qemu_send_packet_async_with_flags(sender, QEMU_NET_PACKET_FLAG_NONE,
 695                                              buf, size, sent_cb);
 696 }
 697
 698 void qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size)
 699 {
 700     qemu_send_packet_async(nc, buf, size, NULL);
 701 }
 702
 703 ssize_t qemu_send_packet_raw(NetClientState *nc, const uint8_t *buf, int size)
 704 {
 705     return qemu_send_packet_async_with_flags(nc, QEMU_NET_PACKET_FLAG_RAW,
 706                                              buf, size, NULL);
 707 }
 708
 709 static ssize_t nc_sendv_compat(NetClientState *nc, const struct iovec *iov,
 710                                int iovcnt, unsigned flags)
 711 {
 712     uint8_t buf[NET_BUFSIZE];
 713     uint8_t *buffer;
 714     size_t offset;
 715
 716     if (iovcnt == 1) {
 717         buffer = iov[0].iov_base;
 718         offset = iov[0].iov_len;
 719     } else {
 720         buffer = buf;
 721         offset = iov_to_buf(iov, iovcnt, 0, buf, sizeof(buf));
 722     }
 723
 724     if (flags & QEMU_NET_PACKET_FLAG_RAW && nc->info->receive_raw) {
 725         return nc->info->receive_raw(nc, buffer, offset);
 726     } else {
 727         return nc->info->receive(nc, buffer, offset);
 728     }
 729 }
 730
 731 ssize_t qemu_deliver_packet_iov(NetClientState *sender,
 732                                 unsigned flags,
 733                                 const struct iovec *iov,
 734                                 int iovcnt,
 735                                 void *opaque)
 736 {
 737     NetClientState *nc = opaque;
 738     int ret;
 739
 740     if (nc->link_down) {
 741         return iov_size(iov, iovcnt);
 742     }
 743
 744     if (nc->receive_disabled) {
 745         return 0;
 746     }
 747
 748     if (nc->info->receive_iov) {
 749         ret = nc->info->receive_iov(nc, iov, iovcnt);
 750     } else {
 751         ret = nc_sendv_compat(nc, iov, iovcnt, flags);
 752     }
 753
 754     if (ret == 0) {
 755         nc->receive_disabled = 1;
 756     }
 757
 758     return ret;
 759 }
 760
 761 ssize_t qemu_sendv_packet_async(NetClientState *sender,
 762                                 const struct iovec *iov, int iovcnt,
 763                                 NetPacketSent *sent_cb)
 764 {
 765     NetQueue *queue;
 766     int ret;
 767
 768     if (sender->link_down || !sender->peer) {
 769         return iov_size(iov, iovcnt);
 770     }
 771
 772     /* Let filters handle the packet first */
 773     ret = filter_receive_iov(sender, NET_FILTER_DIRECTION_TX, sender,
 774                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
 775     if (ret) {
 776         return ret;
 777     }
 778
 779     ret = filter_receive_iov(sender->peer, NET_FILTER_DIRECTION_RX, sender,
 780                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
 781     if (ret) {
 782         return ret;
 783     }
 784
 785     queue = sender->peer->incoming_queue;
 786
 787     return qemu_net_queue_send_iov(queue, sender,
 788                                    QEMU_NET_PACKET_FLAG_NONE,
 789                                    iov, iovcnt, sent_cb);
 790 }
 791
 792 ssize_t
 793 qemu_sendv_packet(NetClientState *nc, const struct iovec *iov, int iovcnt)
 794 {
 795     return qemu_sendv_packet_async(nc, iov, iovcnt, NULL);
 796 }
 797
 798 NetClientState *qemu_find_netdev(const char *id)
 799 {
 800     NetClientState *nc;
 801
 802     QTAILQ_FOREACH(nc, &net_clients, next) {
 803         if (nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC)
 804             continue;
 805         if (!strcmp(nc->name, id)) {
 806             return nc;
 807         }
 808     }
 809
 810     return NULL;
 811 }
 812
 813 int qemu_find_net_clients_except(const char *id, NetClientState **ncs,
 814                                  NetClientOptionsKind type, int max)
 815 {
 816     NetClientState *nc;
 817     int ret = 0;
 818
 819     QTAILQ_FOREACH(nc, &net_clients, next) {
 820         if (nc->info->type == type) {
 821             continue;
 822         }
 823         if (!id || !strcmp(nc->name, id)) {
 824             if (ret < max) {
 825                 ncs[ret] = nc;
 826             }
 827             ret++;
 828         }
 829     }
 830
 831     return ret;
 832 }
 833
 834 static int nic_get_free_idx(void)
 835 {
 836     int index;
 837
 838     for (index = 0; index < MAX_NICS; index++)
 839         if (!nd_table[index].used)
 840             return index;
 841     return -1;
 842 }
 843
 844 int qemu_show_nic_models(const char *arg, const char *const *models)
 845 {
 846     int i;
 847
 848     if (!arg || !is_help_option(arg)) {
 849         return 0;
 850     }
 851
 852     fprintf(stderr, "qemu: Supported NIC models: ");
 853     for (i = 0 ; models[i]; i++)
 854         fprintf(stderr, "%s%c", models[i], models[i+1] ? ',' : '\n');
 855     return 1;
 856 }
 857
 858 void qemu_check_nic_model(NICInfo *nd, const char *model)
 859 {
 860     const char *models[2];
 861
 862     models[0] = model;
 863     models[1] = NULL;
 864
 865     if (qemu_show_nic_models(nd->model, models))
 866         exit(0);
 867     if (qemu_find_nic_model(nd, models, model) < 0)
 868         exit(1);
 869 }
 870
 871 int qemu_find_nic_model(NICInfo *nd, const char * const *models,
 872                         const char *default_model)
 873 {
 874     int i;
 875
 876     if (!nd->model)
 877         nd->model = g_strdup(default_model);
 878
 879     for (i = 0 ; models[i]; i++) {
 880         if (strcmp(nd->model, models[i]) == 0)
 881             return i;
 882     }
 883
 884     error_report("Unsupported NIC model: %s", nd->model);
 885     return -1;
 886 }
 887
 888 static int net_init_nic(const NetClientOptions *opts, const char *name,
 889                         NetClientState *peer, Error **errp)
 890 {
 891     int idx;
 892     NICInfo *nd;
 893     const NetLegacyNicOptions *nic;
 894
 895     assert(opts->type == NET_CLIENT_OPTIONS_KIND_NIC);
 896     nic = opts->u.nic;
 897
 898     idx = nic_get_free_idx();
 899     if (idx == -1 || nb_nics >= MAX_NICS) {
 900         error_setg(errp, "too many NICs");
 901         return -1;
 902     }
 903
 904     nd = &nd_table[idx];
 905
 906     memset(nd, 0, sizeof(*nd));
 907
 908     if (nic->has_netdev) {
 909         nd->netdev = qemu_find_netdev(nic->netdev);
 910         if (!nd->netdev) {
 911             error_setg(errp, "netdev '%s' not found", nic->netdev);
 912             return -1;
 913         }
 914     } else {
 915         assert(peer);
 916         nd->netdev = peer;
 917     }
 918     nd->name = g_strdup(name);
 919     if (nic->has_model) {
 920         nd->model = g_strdup(nic->model);
 921     }
 922     if (nic->has_addr) {
 923         nd->devaddr = g_strdup(nic->addr);
 924     }
 925
 926     if (nic->has_macaddr &&
 927         net_parse_macaddr(nd->macaddr.a, nic->macaddr) < 0) {
 928         error_setg(errp, "invalid syntax for ethernet address");
 929         return -1;
 930     }
 931     if (nic->has_macaddr &&
 932         is_multicast_ether_addr(nd->macaddr.a)) {
 933         error_setg(errp,
 934                    "NIC cannot have multicast MAC address (odd 1st byte)");
 935         return -1;
 936     }
 937     qemu_macaddr_default_if_unset(&nd->macaddr);
 938
 939     if (nic->has_vectors) {
 940         if (nic->vectors > 0x7ffffff) {
 941             error_setg(errp, "invalid # of vectors: %"PRIu32, nic->vectors);
 942             return -1;
 943         }
 944         nd->nvectors = nic->vectors;
 945     } else {
 946         nd->nvectors = DEV_NVECTORS_UNSPECIFIED;
 947     }
 948
 949     nd->used = 1;
 950     nb_nics++;
 951
 952     return idx;
 953 }
 954
 955
 956 static int (* const net_client_init_fun[NET_CLIENT_OPTIONS_KIND__MAX])(
 957     const NetClientOptions *opts,
 958     const char *name,
 959     NetClientState *peer, Error **errp) = {
 960         [NET_CLIENT_OPTIONS_KIND_NIC]       = net_init_nic,
 961 #ifdef CONFIG_SLIRP
 962         [NET_CLIENT_OPTIONS_KIND_USER]      = net_init_slirp,
 963 #endif
 964         [NET_CLIENT_OPTIONS_KIND_TAP]       = net_init_tap,
 965         [NET_CLIENT_OPTIONS_KIND_SOCKET]    = net_init_socket,
 966 #ifdef CONFIG_VDE
 967         [NET_CLIENT_OPTIONS_KIND_VDE]       = net_init_vde,
 968 #endif
 969 #ifdef CONFIG_NETMAP
 970         [NET_CLIENT_OPTIONS_KIND_NETMAP]    = net_init_netmap,
 971 #endif
 972         [NET_CLIENT_OPTIONS_KIND_DUMP]      = net_init_dump,
 973 #ifdef CONFIG_NET_BRIDGE
 974         [NET_CLIENT_OPTIONS_KIND_BRIDGE]    = net_init_bridge,
 975 #endif
 976         [NET_CLIENT_OPTIONS_KIND_HUBPORT]   = net_init_hubport,
 977 #ifdef CONFIG_VHOST_NET_USED
 978         [NET_CLIENT_OPTIONS_KIND_VHOST_USER] = net_init_vhost_user,
 979 #endif
 980 #ifdef CONFIG_L2TPV3
 981         [NET_CLIENT_OPTIONS_KIND_L2TPV3]    = net_init_l2tpv3,
 982 #endif
 983 };
 984
 985
 986 static int net_client_init1(const void *object, int is_netdev, Error **errp)
 987 {
 988     const NetClientOptions *opts;
 989     const char *name;
 990     NetClientState *peer = NULL;
 991
 992     if (is_netdev) {
 993         const Netdev *netdev = object;
 994         opts = netdev->opts;
 995         name = netdev->id;
 996
 997         if (opts->type == NET_CLIENT_OPTIONS_KIND_DUMP ||
 998             opts->type == NET_CLIENT_OPTIONS_KIND_NIC ||
 999             !net_client_init_fun[opts->type]) {
1000             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
1001                        "a netdev backend type");
1002             return -1;
1003         }
1004     } else {
1005         const NetLegacy *net = object;
1006         opts = net->opts;
1007         /* missing optional values have been initialized to "all bits zero" */
1008         name = net->has_id ? net->id : net->name;
1009
1010         if (opts->type == NET_CLIENT_OPTIONS_KIND_NONE) {
1011             return 0; /* nothing to do */
1012         }
1013         if (opts->type == NET_CLIENT_OPTIONS_KIND_HUBPORT) {
1014             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
1015                        "a net type");
1016             return -1;
1017         }
1018
1019         if (!net_client_init_fun[opts->type]) {
1020             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
1021                        "a net backend type (maybe it is not compiled "
1022                        "into this binary)");
1023             return -1;
1024         }
1025
1026         /* Do not add to a vlan if it's a nic with a netdev= parameter. */
1027         if (opts->type != NET_CLIENT_OPTIONS_KIND_NIC ||
1028             !opts->u.nic->has_netdev) {
1029             peer = net_hub_add_port(net->has_vlan ? net->vlan : 0, NULL);
1030         }
1031     }
1032
1033     if (net_client_init_fun[opts->type](opts, name, peer, errp) < 0) {
1034         /* FIXME drop when all init functions store an Error */
1035         if (errp && !*errp) {
1036             error_setg(errp, QERR_DEVICE_INIT_FAILED,
1037                        NetClientOptionsKind_lookup[opts->type]);
1038         }
1039         return -1;
1040     }
1041     return 0;
1042 }
1043
1044
1045 int net_client_init(QemuOpts *opts, int is_netdev, Error **errp)
1046 {
1047     void *object = NULL;
1048     Error *err = NULL;
1049     int ret = -1;
1050     OptsVisitor *ov = opts_visitor_new(opts);
1051     Visitor *v = opts_get_visitor(ov);
1052
1053     {
1054         /* Parse convenience option format ip6-net=fec0::0[/64] */
1055         const char *ip6_net = qemu_opt_get(opts, "ip6-net");
1056
1057         if (ip6_net) {
1058             char buf[strlen(ip6_net) + 1];
1059
1060             if (get_str_sep(buf, sizeof(buf), &ip6_net, '/') < 0) {
1061                 /* Default 64bit prefix length.  */
1062                 qemu_opt_set(opts, "ip6-prefix", ip6_net, &error_abort);
1063                 qemu_opt_set_number(opts, "ip6-prefixlen", 64, &error_abort);
1064             } else {
1065                 /* User-specified prefix length.  */
1066                 unsigned long len;
1067                 int err;
1068
1069                 qemu_opt_set(opts, "ip6-prefix", buf, &error_abort);
1070                 err = qemu_strtoul(ip6_net, NULL, 10, &len);
1071
1072                 if (err) {
1073                     error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1074                               "ip6-prefix", "a number");
1075                 } else {
1076                     qemu_opt_set_number(opts, "ip6-prefixlen", len,
1077                                         &error_abort);
1078                 }
1079             }
1080             qemu_opt_unset(opts, "ip6-net");
1081         }
1082     }
1083
1084     if (is_netdev) {
1085         visit_type_Netdev(v, NULL, (Netdev **)&object, &err);
1086     } else {
1087         visit_type_NetLegacy(v, NULL, (NetLegacy **)&object, &err);
1088     }
1089
1090     if (!err) {
1091         ret = net_client_init1(object, is_netdev, &err);
1092     }
1093
1094     if (is_netdev) {
1095         qapi_free_Netdev(object);
1096     } else {
1097         qapi_free_NetLegacy(object);
1098     }
1099
1100     error_propagate(errp, err);
1101     return ret;
1102 }
1103
1104
1105 static int net_host_check_device(const char *device)
1106 {
1107     int i;
1108     for (i = 0; host_net_devices[i]; i++) {
1109         if (!strncmp(host_net_devices[i], device,
1110                      strlen(host_net_devices[i]))) {
1111             return 1;
1112         }
1113     }
1114
1115     return 0;
1116 }
1117
1118 void hmp_host_net_add(Monitor *mon, const QDict *qdict)
1119 {
1120     const char *device = qdict_get_str(qdict, "device");
1121     const char *opts_str = qdict_get_try_str(qdict, "opts");
1122     Error *local_err = NULL;
1123     QemuOpts *opts;
1124
1125     if (!net_host_check_device(device)) {
1126         monitor_printf(mon, "invalid host network device %s\n", device);
1127         return;
1128     }
1129
1130     opts = qemu_opts_parse_noisily(qemu_find_opts("net"),
1131                                    opts_str ? opts_str : "", false);
1132     if (!opts) {
1133         return;
1134     }
1135
1136     qemu_opt_set(opts, "type", device, &error_abort);
1137
1138     net_client_init(opts, 0, &local_err);
1139     if (local_err) {
1140         error_report_err(local_err);
1141         monitor_printf(mon, "adding host network device %s failed\n", device);
1142     }
1143 }
1144
1145 void hmp_host_net_remove(Monitor *mon, const QDict *qdict)
1146 {
1147     NetClientState *nc;
1148     int vlan_id = qdict_get_int(qdict, "vlan_id");
1149     const char *device = qdict_get_str(qdict, "device");
1150
1151     nc = net_hub_find_client_by_name(vlan_id, device);
1152     if (!nc) {
1153         error_report("Host network device '%s' on hub '%d' not found",
1154                      device, vlan_id);
1155         return;
1156     }
1157     if (nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
1158         error_report("invalid host network device '%s'", device);
1159         return;
1160     }
1161
1162     qemu_del_net_client(nc->peer);
1163     qemu_del_net_client(nc);
1164 }
1165
1166 void netdev_add(QemuOpts *opts, Error **errp)
1167 {
1168     net_client_init(opts, 1, errp);
1169 }
1170
1171 void qmp_netdev_add(QDict *qdict, QObject **ret, Error **errp)
1172 {
1173     Error *local_err = NULL;
1174     QemuOptsList *opts_list;
1175     QemuOpts *opts;
1176
1177     opts_list = qemu_find_opts_err("netdev", &local_err);
1178     if (local_err) {
1179         goto out;
1180     }
1181
1182     opts = qemu_opts_from_qdict(opts_list, qdict, &local_err);
1183     if (local_err) {
1184         goto out;
1185     }
1186
1187     netdev_add(opts, &local_err);
1188     if (local_err) {
1189         qemu_opts_del(opts);
1190         goto out;
1191     }
1192
1193 out:
1194     error_propagate(errp, local_err);
1195 }
1196
1197 void qmp_netdev_del(const char *id, Error **errp)
1198 {
1199     NetClientState *nc;
1200     QemuOpts *opts;
1201
1202     nc = qemu_find_netdev(id);
1203     if (!nc) {
1204         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1205                   "Device '%s' not found", id);
1206         return;
1207     }
1208
1209     opts = qemu_opts_find(qemu_find_opts_err("netdev", NULL), id);
1210     if (!opts) {
1211         error_setg(errp, "Device '%s' is not a netdev", id);
1212         return;
1213     }
1214
1215     qemu_del_net_client(nc);
1216     qemu_opts_del(opts);
1217 }
1218
1219 static void netfilter_print_info(Monitor *mon, NetFilterState *nf)
1220 {
1221     char *str;
1222     ObjectProperty *prop;
1223     ObjectPropertyIterator iter;
1224     StringOutputVisitor *ov;
1225
1226     /* generate info str */
1227     object_property_iter_init(&iter, OBJECT(nf));
1228     while ((prop = object_property_iter_next(&iter))) {
1229         if (!strcmp(prop->name, "type")) {
1230             continue;
1231         }
1232         ov = string_output_visitor_new(false);
1233         object_property_get(OBJECT(nf), string_output_get_visitor(ov),
1234                             prop->name, NULL);
1235         str = string_output_get_string(ov);
1236         string_output_visitor_cleanup(ov);
1237         monitor_printf(mon, ",%s=%s", prop->name, str);
1238         g_free(str);
1239     }
1240     monitor_printf(mon, "\n");
1241 }
1242
1243 void print_net_client(Monitor *mon, NetClientState *nc)
1244 {
1245     NetFilterState *nf;
1246
1247     monitor_printf(mon, "%s: index=%d,type=%s,%s\n", nc->name,
1248                    nc->queue_index,
1249                    NetClientOptionsKind_lookup[nc->info->type],
1250                    nc->info_str);
1251     if (!QTAILQ_EMPTY(&nc->filters)) {
1252         monitor_printf(mon, "filters:\n");
1253     }
1254     QTAILQ_FOREACH(nf, &nc->filters, next) {
1255         char *path = object_get_canonical_path_component(OBJECT(nf));
1256
1257         monitor_printf(mon, "  - %s: type=%s", path,
1258                        object_get_typename(OBJECT(nf)));
1259         netfilter_print_info(mon, nf);
1260         g_free(path);
1261     }
1262 }
1263
1264 RxFilterInfoList *qmp_query_rx_filter(bool has_name, const char *name,
1265                                       Error **errp)
1266 {
1267     NetClientState *nc;
1268     RxFilterInfoList *filter_list = NULL, *last_entry = NULL;
1269
1270     QTAILQ_FOREACH(nc, &net_clients, next) {
1271         RxFilterInfoList *entry;
1272         RxFilterInfo *info;
1273
1274         if (has_name && strcmp(nc->name, name) != 0) {
1275             continue;
1276         }
1277
1278         /* only query rx-filter information of NIC */
1279         if (nc->info->type != NET_CLIENT_OPTIONS_KIND_NIC) {
1280             if (has_name) {
1281                 error_setg(errp, "net client(%s) isn't a NIC", name);
1282                 return NULL;
1283             }
1284             continue;
1285         }
1286
1287         /* only query information on queue 0 since the info is per nic,
1288          * not per queue
1289          */
1290         if (nc->queue_index != 0)
1291             continue;
1292
1293         if (nc->info->query_rx_filter) {
1294             info = nc->info->query_rx_filter(nc);
1295             entry = g_malloc0(sizeof(*entry));
1296             entry->value = info;
1297
1298             if (!filter_list) {
1299                 filter_list = entry;
1300             } else {
1301                 last_entry->next = entry;
1302             }
1303             last_entry = entry;
1304         } else if (has_name) {
1305             error_setg(errp, "net client(%s) doesn't support"
1306                        " rx-filter querying", name);
1307             return NULL;
1308         }
1309
1310         if (has_name) {
1311             break;
1312         }
1313     }
1314
1315     if (filter_list == NULL && has_name) {
1316         error_setg(errp, "invalid net client name: %s", name);
1317     }
1318
1319     return filter_list;
1320 }
1321
1322 void hmp_info_network(Monitor *mon, const QDict *qdict)
1323 {
1324     NetClientState *nc, *peer;
1325     NetClientOptionsKind type;
1326
1327     net_hub_info(mon);
1328
1329     QTAILQ_FOREACH(nc, &net_clients, next) {
1330         peer = nc->peer;
1331         type = nc->info->type;
1332
1333         /* Skip if already printed in hub info */
1334         if (net_hub_id_for_client(nc, NULL) == 0) {
1335             continue;
1336         }
1337
1338         if (!peer || type == NET_CLIENT_OPTIONS_KIND_NIC) {
1339             print_net_client(mon, nc);
1340         } /* else it's a netdev connected to a NIC, printed with the NIC */
1341         if (peer && type == NET_CLIENT_OPTIONS_KIND_NIC) {
1342             monitor_printf(mon, " \\ ");
1343             print_net_client(mon, peer);
1344         }
1345     }
1346 }
1347
1348 void qmp_set_link(const char *name, bool up, Error **errp)
1349 {
1350     NetClientState *ncs[MAX_QUEUE_NUM];
1351     NetClientState *nc;
1352     int queues, i;
1353
1354     queues = qemu_find_net_clients_except(name, ncs,
1355                                           NET_CLIENT_OPTIONS_KIND__MAX,
1356                                           MAX_QUEUE_NUM);
1357
1358     if (queues == 0) {
1359         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1360                   "Device '%s' not found", name);
1361         return;
1362     }
1363     nc = ncs[0];
1364
1365     for (i = 0; i < queues; i++) {
1366         ncs[i]->link_down = !up;
1367     }
1368
1369     if (nc->info->link_status_changed) {
1370         nc->info->link_status_changed(nc);
1371     }
1372
1373     if (nc->peer) {
1374         /* Change peer link only if the peer is NIC and then notify peer.
1375          * If the peer is a HUBPORT or a backend, we do not change the
1376          * link status.
1377          *
1378          * This behavior is compatible with qemu vlans where there could be
1379          * multiple clients that can still communicate with each other in
1380          * disconnected mode. For now maintain this compatibility.
1381          */
1382         if (nc->peer->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
1383             for (i = 0; i < queues; i++) {
1384                 ncs[i]->peer->link_down = !up;
1385             }
1386         }
1387         if (nc->peer->info->link_status_changed) {
1388             nc->peer->info->link_status_changed(nc->peer);
1389         }
1390     }
1391 }
1392
1393 static void net_vm_change_state_handler(void *opaque, int running,
1394                                         RunState state)
1395 {
1396     NetClientState *nc;
1397     NetClientState *tmp;
1398
1399     QTAILQ_FOREACH_SAFE(nc, &net_clients, next, tmp) {
1400         if (running) {
1401             /* Flush queued packets and wake up backends. */
1402             if (nc->peer && qemu_can_send_packet(nc)) {
1403                 qemu_flush_queued_packets(nc->peer);
1404             }
1405         } else {
1406             /* Complete all queued packets, to guarantee we don't modify
1407              * state later when VM is not running.
1408              */
1409             qemu_flush_or_purge_queued_packets(nc, true);
1410         }
1411     }
1412 }
1413
1414 void net_cleanup(void)
1415 {
1416     NetClientState *nc;
1417
1418     /* We may del multiple entries during qemu_del_net_client(),
1419      * so QTAILQ_FOREACH_SAFE() is also not safe here.
1420      */
1421     while (!QTAILQ_EMPTY(&net_clients)) {
1422         nc = QTAILQ_FIRST(&net_clients);
1423         if (nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
1424             qemu_del_nic(qemu_get_nic(nc));
1425         } else {
1426             qemu_del_net_client(nc);
1427         }
1428     }
1429
1430     qemu_del_vm_change_state_handler(net_change_state_entry);
1431 }
1432
1433 void net_check_clients(void)
1434 {
1435     NetClientState *nc;
1436     int i;
1437
1438     /* Don't warn about the default network setup that you get if
1439      * no command line -net or -netdev options are specified. There
1440      * are two cases that we would otherwise complain about:
1441      * (1) board doesn't support a NIC but the implicit "-net nic"
1442      * requested one
1443      * (2) CONFIG_SLIRP not set, in which case the implicit "-net nic"
1444      * sets up a nic that isn't connected to anything.
1445      */
1446     if (default_net) {
1447         return;
1448     }
1449
1450     net_hub_check_clients();
1451
1452     QTAILQ_FOREACH(nc, &net_clients, next) {
1453         if (!nc->peer) {
1454             fprintf(stderr, "Warning: %s %s has no peer\n",
1455                     nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC ?
1456                     "nic" : "netdev", nc->name);
1457         }
1458     }
1459
1460     /* Check that all NICs requested via -net nic actually got created.
1461      * NICs created via -device don't need to be checked here because
1462      * they are always instantiated.
1463      */
1464     for (i = 0; i < MAX_NICS; i++) {
1465         NICInfo *nd = &nd_table[i];
1466         if (nd->used && !nd->instantiated) {
1467             fprintf(stderr, "Warning: requested NIC (%s, model %s) "
1468                     "was not created (not supported by this machine?)\n",
1469                     nd->name ? nd->name : "anonymous",
1470                     nd->model ? nd->model : "unspecified");
1471         }
1472     }
1473 }
1474
1475 static int net_init_client(void *dummy, QemuOpts *opts, Error **errp)
1476 {
1477     Error *local_err = NULL;
1478
1479     net_client_init(opts, 0, &local_err);
1480     if (local_err) {
1481         error_report_err(local_err);
1482         return -1;
1483     }
1484
1485     return 0;
1486 }
1487
1488 static int net_init_netdev(void *dummy, QemuOpts *opts, Error **errp)
1489 {
1490     Error *local_err = NULL;
1491     int ret;
1492
1493     ret = net_client_init(opts, 1, &local_err);
1494     if (local_err) {
1495         error_report_err(local_err);
1496         return -1;
1497     }
1498
1499     return ret;
1500 }
1501
1502 int net_init_clients(void)
1503 {
1504     QemuOptsList *net = qemu_find_opts("net");
1505
1506     if (default_net) {
1507         /* if no clients, we use a default config */
1508         qemu_opts_set(net, NULL, "type", "nic", &error_abort);
1509 #ifdef CONFIG_SLIRP
1510         qemu_opts_set(net, NULL, "type", "user", &error_abort);
1511 #endif
1512     }
1513
1514     net_change_state_entry =
1515         qemu_add_vm_change_state_handler(net_vm_change_state_handler, NULL);
1516
1517     QTAILQ_INIT(&net_clients);
1518
1519     if (qemu_opts_foreach(qemu_find_opts("netdev"),
1520                           net_init_netdev, NULL, NULL)) {
1521         return -1;
1522     }
1523
1524     if (qemu_opts_foreach(net, net_init_client, NULL, NULL)) {
1525         return -1;
1526     }
1527
1528     return 0;
1529 }
1530
1531 int net_client_parse(QemuOptsList *opts_list, const char *optarg)
1532 {
1533 #if defined(CONFIG_SLIRP)
1534     int ret;
1535     if (net_slirp_parse_legacy(opts_list, optarg, &ret)) {
1536         return ret;
1537     }
1538 #endif
1539
1540     if (!qemu_opts_parse_noisily(opts_list, optarg, true)) {
1541         return -1;
1542     }
1543
1544     default_net = 0;
1545     return 0;
1546 }
1547
1548 /* From FreeBSD */
1549 /* XXX: optimize */
1550 unsigned compute_mcast_idx(const uint8_t *ep)
1551 {
1552     uint32_t crc;
1553     int carry, i, j;
1554     uint8_t b;
1555
1556     crc = 0xffffffff;
1557     for (i = 0; i < 6; i++) {
1558         b = *ep++;
1559         for (j = 0; j < 8; j++) {
1560             carry = ((crc & 0x80000000L) ? 1 : 0) ^ (b & 0x01);
1561             crc <<= 1;
1562             b >>= 1;
1563             if (carry) {
1564                 crc = ((crc ^ POLYNOMIAL) | carry);
1565             }
1566         }
1567     }
1568     return crc >> 26;
1569 }
1570
1571 QemuOptsList qemu_netdev_opts = {
1572     .name = "netdev",
1573     .implied_opt_name = "type",
1574     .head = QTAILQ_HEAD_INITIALIZER(qemu_netdev_opts.head),
1575     .desc = {
1576         /*
1577          * no elements => accept any params
1578          * validation will happen later
1579          */
1580         { /* end of list */ }
1581     },
1582 };
1583
1584 QemuOptsList qemu_net_opts = {
1585     .name = "net",
1586     .implied_opt_name = "type",
1587     .head = QTAILQ_HEAD_INITIALIZER(qemu_net_opts.head),
1588     .desc = {
1589         /*
1590          * no elements => accept any params
1591          * validation will happen later
1592          */
1593         { /* end of list */ }
1594     },
1595 };