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
  25 #include "qemu/osdep.h"
  26
  27 #include "net/net.h"
  28 #include "clients.h"
  29 #include "hub.h"
  30 #include "hw/qdev-properties.h"
  31 #include "net/slirp.h"
  32 #include "net/eth.h"
  33 #include "util.h"
  34
  35 #include "monitor/monitor.h"
  36 #include "qemu/help_option.h"
  37 #include "qapi/qapi-commands-net.h"
  38 #include "qapi/qapi-visit-net.h"
  39 #include "qapi/qmp/qdict.h"
  40 #include "qapi/qmp/qerror.h"
  41 #include "qemu/error-report.h"
  42 #include "qemu/sockets.h"
  43 #include "qemu/cutils.h"
  44 #include "qemu/config-file.h"
  45 #include "qemu/ctype.h"
  46 #include "qemu/id.h"
  47 #include "qemu/iov.h"
  48 #include "qemu/qemu-print.h"
  49 #include "qemu/main-loop.h"
  50 #include "qemu/option.h"
  51 #include "qapi/error.h"
  52 #include "qapi/opts-visitor.h"
  53 #include "sysemu/sysemu.h"
  54 #include "sysemu/runstate.h"
  55 #include "sysemu/sysemu.h"
  56 #include "net/filter.h"
  57 #include "qapi/string-output-visitor.h"
  58
  59 /* Net bridge is currently not supported for W32. */
  60 #if !defined(_WIN32)
  61 # define CONFIG_NET_BRIDGE
  62 #endif
  63
  64 static VMChangeStateEntry *net_change_state_entry;
  65 static QTAILQ_HEAD(, NetClientState) net_clients;
  66
  67 /***********************************************************/
  68 /* network device redirectors */
  69
  70 int parse_host_port(struct sockaddr_in *saddr, const char *str,
  71                     Error **errp)
  72 {
  73     gchar **substrings;
  74     struct hostent *he;
  75     const char *addr, *p, *r;
  76     int port, ret = 0;
  77
  78     substrings = g_strsplit(str, ":", 2);
  79     if (!substrings || !substrings[0] || !substrings[1]) {
  80         error_setg(errp, "host address '%s' doesn't contain ':' "
  81                    "separating host from port", str);
  82         ret = -1;
  83         goto out;
  84     }
  85
  86     addr = substrings[0];
  87     p = substrings[1];
  88
  89     saddr->sin_family = AF_INET;
  90     if (addr[0] == '\0') {
  91         saddr->sin_addr.s_addr = 0;
  92     } else {
  93         if (qemu_isdigit(addr[0])) {
  94             if (!inet_aton(addr, &saddr->sin_addr)) {
  95                 error_setg(errp, "host address '%s' is not a valid "
  96                            "IPv4 address", addr);
  97                 ret = -1;
  98                 goto out;
  99             }
 100         } else {
 101             he = gethostbyname(addr);
 102             if (he == NULL) {
 103                 error_setg(errp, "can't resolve host address '%s'", addr);
 104                 ret = -1;
 105                 goto out;
 106             }
 107             saddr->sin_addr = *(struct in_addr *)he->h_addr;
 108         }
 109     }
 110     port = strtol(p, (char **)&r, 0);
 111     if (r == p) {
 112         error_setg(errp, "port number '%s' is invalid", p);
 113         ret = -1;
 114         goto out;
 115     }
 116     saddr->sin_port = htons(port);
 117
 118 out:
 119     g_strfreev(substrings);
 120     return ret;
 121 }
 122
 123 char *qemu_mac_strdup_printf(const uint8_t *macaddr)
 124 {
 125     return g_strdup_printf("%.2x:%.2x:%.2x:%.2x:%.2x:%.2x",
 126                            macaddr[0], macaddr[1], macaddr[2],
 127                            macaddr[3], macaddr[4], macaddr[5]);
 128 }
 129
 130 void qemu_format_nic_info_str(NetClientState *nc, uint8_t macaddr[6])
 131 {
 132     snprintf(nc->info_str, sizeof(nc->info_str),
 133              "model=%s,macaddr=%02x:%02x:%02x:%02x:%02x:%02x",
 134              nc->model,
 135              macaddr[0], macaddr[1], macaddr[2],
 136              macaddr[3], macaddr[4], macaddr[5]);
 137 }
 138
 139 static int mac_table[256] = {0};
 140
 141 static void qemu_macaddr_set_used(MACAddr *macaddr)
 142 {
 143     int index;
 144
 145     for (index = 0x56; index < 0xFF; index++) {
 146         if (macaddr->a[5] == index) {
 147             mac_table[index]++;
 148         }
 149     }
 150 }
 151
 152 static void qemu_macaddr_set_free(MACAddr *macaddr)
 153 {
 154     int index;
 155     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
 156
 157     if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
 158         return;
 159     }
 160     for (index = 0x56; index < 0xFF; index++) {
 161         if (macaddr->a[5] == index) {
 162             mac_table[index]--;
 163         }
 164     }
 165 }
 166
 167 static int qemu_macaddr_get_free(void)
 168 {
 169     int index;
 170
 171     for (index = 0x56; index < 0xFF; index++) {
 172         if (mac_table[index] == 0) {
 173             return index;
 174         }
 175     }
 176
 177     return -1;
 178 }
 179
 180 void qemu_macaddr_default_if_unset(MACAddr *macaddr)
 181 {
 182     static const MACAddr zero = { .a = { 0,0,0,0,0,0 } };
 183     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
 184
 185     if (memcmp(macaddr, &zero, sizeof(zero)) != 0) {
 186         if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
 187             return;
 188         } else {
 189             qemu_macaddr_set_used(macaddr);
 190             return;
 191         }
 192     }
 193
 194     macaddr->a[0] = 0x52;
 195     macaddr->a[1] = 0x54;
 196     macaddr->a[2] = 0x00;
 197     macaddr->a[3] = 0x12;
 198     macaddr->a[4] = 0x34;
 199     macaddr->a[5] = qemu_macaddr_get_free();
 200     qemu_macaddr_set_used(macaddr);
 201 }
 202
 203 /**
 204  * Generate a name for net client
 205  *
 206  * Only net clients created with the legacy -net option and NICs need this.
 207  */
 208 static char *assign_name(NetClientState *nc1, const char *model)
 209 {
 210     NetClientState *nc;
 211     int id = 0;
 212
 213     QTAILQ_FOREACH(nc, &net_clients, next) {
 214         if (nc == nc1) {
 215             continue;
 216         }
 217         if (strcmp(nc->model, model) == 0) {
 218             id++;
 219         }
 220     }
 221
 222     return g_strdup_printf("%s.%d", model, id);
 223 }
 224
 225 static void qemu_net_client_destructor(NetClientState *nc)
 226 {
 227     g_free(nc);
 228 }
 229 static ssize_t qemu_deliver_packet_iov(NetClientState *sender,
 230                                        unsigned flags,
 231                                        const struct iovec *iov,
 232                                        int iovcnt,
 233                                        void *opaque);
 234
 235 static void qemu_net_client_setup(NetClientState *nc,
 236                                   NetClientInfo *info,
 237                                   NetClientState *peer,
 238                                   const char *model,
 239                                   const char *name,
 240                                   NetClientDestructor *destructor)
 241 {
 242     nc->info = info;
 243     nc->model = g_strdup(model);
 244     if (name) {
 245         nc->name = g_strdup(name);
 246     } else {
 247         nc->name = assign_name(nc, model);
 248     }
 249
 250     if (peer) {
 251         assert(!peer->peer);
 252         nc->peer = peer;
 253         peer->peer = nc;
 254     }
 255     QTAILQ_INSERT_TAIL(&net_clients, nc, next);
 256
 257     nc->incoming_queue = qemu_new_net_queue(qemu_deliver_packet_iov, nc);
 258     nc->destructor = destructor;
 259     QTAILQ_INIT(&nc->filters);
 260 }
 261
 262 NetClientState *qemu_new_net_client(NetClientInfo *info,
 263                                     NetClientState *peer,
 264                                     const char *model,
 265                                     const char *name)
 266 {
 267     NetClientState *nc;
 268
 269     assert(info->size >= sizeof(NetClientState));
 270
 271     nc = g_malloc0(info->size);
 272     qemu_net_client_setup(nc, info, peer, model, name,
 273                           qemu_net_client_destructor);
 274
 275     return nc;
 276 }
 277
 278 NICState *qemu_new_nic(NetClientInfo *info,
 279                        NICConf *conf,
 280                        const char *model,
 281                        const char *name,
 282                        void *opaque)
 283 {
 284     NetClientState **peers = conf->peers.ncs;
 285     NICState *nic;
 286     int i, queues = MAX(1, conf->peers.queues);
 287
 288     assert(info->type == NET_CLIENT_DRIVER_NIC);
 289     assert(info->size >= sizeof(NICState));
 290
 291     nic = g_malloc0(info->size + sizeof(NetClientState) * queues);
 292     nic->ncs = (void *)nic + info->size;
 293     nic->conf = conf;
 294     nic->opaque = opaque;
 295
 296     for (i = 0; i < queues; i++) {
 297         qemu_net_client_setup(&nic->ncs[i], info, peers[i], model, name,
 298                               NULL);
 299         nic->ncs[i].queue_index = i;
 300     }
 301
 302     return nic;
 303 }
 304
 305 NetClientState *qemu_get_subqueue(NICState *nic, int queue_index)
 306 {
 307     return nic->ncs + queue_index;
 308 }
 309
 310 NetClientState *qemu_get_queue(NICState *nic)
 311 {
 312     return qemu_get_subqueue(nic, 0);
 313 }
 314
 315 NICState *qemu_get_nic(NetClientState *nc)
 316 {
 317     NetClientState *nc0 = nc - nc->queue_index;
 318
 319     return (NICState *)((void *)nc0 - nc->info->size);
 320 }
 321
 322 void *qemu_get_nic_opaque(NetClientState *nc)
 323 {
 324     NICState *nic = qemu_get_nic(nc);
 325
 326     return nic->opaque;
 327 }
 328
 329 NetClientState *qemu_get_peer(NetClientState *nc, int queue_index)
 330 {
 331     assert(nc != NULL);
 332     NetClientState *ncs = nc + queue_index;
 333     return ncs->peer;
 334 }
 335
 336 static void qemu_cleanup_net_client(NetClientState *nc)
 337 {
 338     QTAILQ_REMOVE(&net_clients, nc, next);
 339
 340     if (nc->info->cleanup) {
 341         nc->info->cleanup(nc);
 342     }
 343 }
 344
 345 static void qemu_free_net_client(NetClientState *nc)
 346 {
 347     if (nc->incoming_queue) {
 348         qemu_del_net_queue(nc->incoming_queue);
 349     }
 350     if (nc->peer) {
 351         nc->peer->peer = NULL;
 352     }
 353     g_free(nc->name);
 354     g_free(nc->model);
 355     if (nc->destructor) {
 356         nc->destructor(nc);
 357     }
 358 }
 359
 360 void qemu_del_net_client(NetClientState *nc)
 361 {
 362     NetClientState *ncs[MAX_QUEUE_NUM];
 363     int queues, i;
 364     NetFilterState *nf, *next;
 365
 366     assert(nc->info->type != NET_CLIENT_DRIVER_NIC);
 367
 368     /* If the NetClientState belongs to a multiqueue backend, we will change all
 369      * other NetClientStates also.
 370      */
 371     queues = qemu_find_net_clients_except(nc->name, ncs,
 372                                           NET_CLIENT_DRIVER_NIC,
 373                                           MAX_QUEUE_NUM);
 374     assert(queues != 0);
 375
 376     QTAILQ_FOREACH_SAFE(nf, &nc->filters, next, next) {
 377         object_unparent(OBJECT(nf));
 378     }
 379
 380     /* If there is a peer NIC, delete and cleanup client, but do not free. */
 381     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
 382         NICState *nic = qemu_get_nic(nc->peer);
 383         if (nic->peer_deleted) {
 384             return;
 385         }
 386         nic->peer_deleted = true;
 387
 388         for (i = 0; i < queues; i++) {
 389             ncs[i]->peer->link_down = true;
 390         }
 391
 392         if (nc->peer->info->link_status_changed) {
 393             nc->peer->info->link_status_changed(nc->peer);
 394         }
 395
 396         for (i = 0; i < queues; i++) {
 397             qemu_cleanup_net_client(ncs[i]);
 398         }
 399
 400         return;
 401     }
 402
 403     for (i = 0; i < queues; i++) {
 404         qemu_cleanup_net_client(ncs[i]);
 405         qemu_free_net_client(ncs[i]);
 406     }
 407 }
 408
 409 void qemu_del_nic(NICState *nic)
 410 {
 411     int i, queues = MAX(nic->conf->peers.queues, 1);
 412
 413     qemu_macaddr_set_free(&nic->conf->macaddr);
 414
 415     for (i = 0; i < queues; i++) {
 416         NetClientState *nc = qemu_get_subqueue(nic, i);
 417         /* If this is a peer NIC and peer has already been deleted, free it now. */
 418         if (nic->peer_deleted) {
 419             qemu_free_net_client(nc->peer);
 420         } else if (nc->peer) {
 421             /* if there are RX packets pending, complete them */
 422             qemu_purge_queued_packets(nc->peer);
 423         }
 424     }
 425
 426     for (i = queues - 1; i >= 0; i--) {
 427         NetClientState *nc = qemu_get_subqueue(nic, i);
 428
 429         qemu_cleanup_net_client(nc);
 430         qemu_free_net_client(nc);
 431     }
 432
 433     g_free(nic);
 434 }
 435
 436 void qemu_foreach_nic(qemu_nic_foreach func, void *opaque)
 437 {
 438     NetClientState *nc;
 439
 440     QTAILQ_FOREACH(nc, &net_clients, next) {
 441         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
 442             if (nc->queue_index == 0) {
 443                 func(qemu_get_nic(nc), opaque);
 444             }
 445         }
 446     }
 447 }
 448
 449 bool qemu_has_ufo(NetClientState *nc)
 450 {
 451     if (!nc || !nc->info->has_ufo) {
 452         return false;
 453     }
 454
 455     return nc->info->has_ufo(nc);
 456 }
 457
 458 bool qemu_has_vnet_hdr(NetClientState *nc)
 459 {
 460     if (!nc || !nc->info->has_vnet_hdr) {
 461         return false;
 462     }
 463
 464     return nc->info->has_vnet_hdr(nc);
 465 }
 466
 467 bool qemu_has_vnet_hdr_len(NetClientState *nc, int len)
 468 {
 469     if (!nc || !nc->info->has_vnet_hdr_len) {
 470         return false;
 471     }
 472
 473     return nc->info->has_vnet_hdr_len(nc, len);
 474 }
 475
 476 void qemu_using_vnet_hdr(NetClientState *nc, bool enable)
 477 {
 478     if (!nc || !nc->info->using_vnet_hdr) {
 479         return;
 480     }
 481
 482     nc->info->using_vnet_hdr(nc, enable);
 483 }
 484
 485 void qemu_set_offload(NetClientState *nc, int csum, int tso4, int tso6,
 486                           int ecn, int ufo)
 487 {
 488     if (!nc || !nc->info->set_offload) {
 489         return;
 490     }
 491
 492     nc->info->set_offload(nc, csum, tso4, tso6, ecn, ufo);
 493 }
 494
 495 void qemu_set_vnet_hdr_len(NetClientState *nc, int len)
 496 {
 497     if (!nc || !nc->info->set_vnet_hdr_len) {
 498         return;
 499     }
 500
 501     nc->vnet_hdr_len = len;
 502     nc->info->set_vnet_hdr_len(nc, len);
 503 }
 504
 505 int qemu_set_vnet_le(NetClientState *nc, bool is_le)
 506 {
 507 #ifdef HOST_WORDS_BIGENDIAN
 508     if (!nc || !nc->info->set_vnet_le) {
 509         return -ENOSYS;
 510     }
 511
 512     return nc->info->set_vnet_le(nc, is_le);
 513 #else
 514     return 0;
 515 #endif
 516 }
 517
 518 int qemu_set_vnet_be(NetClientState *nc, bool is_be)
 519 {
 520 #ifdef HOST_WORDS_BIGENDIAN
 521     return 0;
 522 #else
 523     if (!nc || !nc->info->set_vnet_be) {
 524         return -ENOSYS;
 525     }
 526
 527     return nc->info->set_vnet_be(nc, is_be);
 528 #endif
 529 }
 530
 531 int qemu_can_send_packet(NetClientState *sender)
 532 {
 533     int vm_running = runstate_is_running();
 534
 535     if (!vm_running) {
 536         return 0;
 537     }
 538
 539     if (!sender->peer) {
 540         return 1;
 541     }
 542
 543     if (sender->peer->receive_disabled) {
 544         return 0;
 545     } else if (sender->peer->info->can_receive &&
 546                !sender->peer->info->can_receive(sender->peer)) {
 547         return 0;
 548     }
 549     return 1;
 550 }
 551
 552 static ssize_t filter_receive_iov(NetClientState *nc,
 553                                   NetFilterDirection direction,
 554                                   NetClientState *sender,
 555                                   unsigned flags,
 556                                   const struct iovec *iov,
 557                                   int iovcnt,
 558                                   NetPacketSent *sent_cb)
 559 {
 560     ssize_t ret = 0;
 561     NetFilterState *nf = NULL;
 562
 563     if (direction == NET_FILTER_DIRECTION_TX) {
 564         QTAILQ_FOREACH(nf, &nc->filters, next) {
 565             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
 566                                          iovcnt, sent_cb);
 567             if (ret) {
 568                 return ret;
 569             }
 570         }
 571     } else {
 572         QTAILQ_FOREACH_REVERSE(nf, &nc->filters, next) {
 573             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
 574                                          iovcnt, sent_cb);
 575             if (ret) {
 576                 return ret;
 577             }
 578         }
 579     }
 580
 581     return ret;
 582 }
 583
 584 static ssize_t filter_receive(NetClientState *nc,
 585                               NetFilterDirection direction,
 586                               NetClientState *sender,
 587                               unsigned flags,
 588                               const uint8_t *data,
 589                               size_t size,
 590                               NetPacketSent *sent_cb)
 591 {
 592     struct iovec iov = {
 593         .iov_base = (void *)data,
 594         .iov_len = size
 595     };
 596
 597     return filter_receive_iov(nc, direction, sender, flags, &iov, 1, sent_cb);
 598 }
 599
 600 void qemu_purge_queued_packets(NetClientState *nc)
 601 {
 602     if (!nc->peer) {
 603         return;
 604     }
 605
 606     qemu_net_queue_purge(nc->peer->incoming_queue, nc);
 607 }
 608
 609 void qemu_flush_or_purge_queued_packets(NetClientState *nc, bool purge)
 610 {
 611     nc->receive_disabled = 0;
 612
 613     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_HUBPORT) {
 614         if (net_hub_flush(nc->peer)) {
 615             qemu_notify_event();
 616         }
 617     }
 618     if (qemu_net_queue_flush(nc->incoming_queue)) {
 619         /* We emptied the queue successfully, signal to the IO thread to repoll
 620          * the file descriptor (for tap, for example).
 621          */
 622         qemu_notify_event();
 623     } else if (purge) {
 624         /* Unable to empty the queue, purge remaining packets */
 625         qemu_net_queue_purge(nc->incoming_queue, nc->peer);
 626     }
 627 }
 628
 629 void qemu_flush_queued_packets(NetClientState *nc)
 630 {
 631     qemu_flush_or_purge_queued_packets(nc, false);
 632 }
 633
 634 static ssize_t qemu_send_packet_async_with_flags(NetClientState *sender,
 635                                                  unsigned flags,
 636                                                  const uint8_t *buf, int size,
 637                                                  NetPacketSent *sent_cb)
 638 {
 639     NetQueue *queue;
 640     int ret;
 641
 642 #ifdef DEBUG_NET
 643     printf("qemu_send_packet_async:\n");
 644     qemu_hexdump(stdout, "net", buf, size);
 645 #endif
 646
 647     if (sender->link_down || !sender->peer) {
 648         return size;
 649     }
 650
 651     /* Let filters handle the packet first */
 652     ret = filter_receive(sender, NET_FILTER_DIRECTION_TX,
 653                          sender, flags, buf, size, sent_cb);
 654     if (ret) {
 655         return ret;
 656     }
 657
 658     ret = filter_receive(sender->peer, NET_FILTER_DIRECTION_RX,
 659                          sender, flags, buf, size, sent_cb);
 660     if (ret) {
 661         return ret;
 662     }
 663
 664     queue = sender->peer->incoming_queue;
 665
 666     return qemu_net_queue_send(queue, sender, flags, buf, size, sent_cb);
 667 }
 668
 669 ssize_t qemu_send_packet_async(NetClientState *sender,
 670                                const uint8_t *buf, int size,
 671                                NetPacketSent *sent_cb)
 672 {
 673     return qemu_send_packet_async_with_flags(sender, QEMU_NET_PACKET_FLAG_NONE,
 674                                              buf, size, sent_cb);
 675 }
 676
 677 ssize_t qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size)
 678 {
 679     return qemu_send_packet_async(nc, buf, size, NULL);
 680 }
 681
 682 ssize_t qemu_send_packet_raw(NetClientState *nc, const uint8_t *buf, int size)
 683 {
 684     return qemu_send_packet_async_with_flags(nc, QEMU_NET_PACKET_FLAG_RAW,
 685                                              buf, size, NULL);
 686 }
 687
 688 static ssize_t nc_sendv_compat(NetClientState *nc, const struct iovec *iov,
 689                                int iovcnt, unsigned flags)
 690 {
 691     uint8_t *buf = NULL;
 692     uint8_t *buffer;
 693     size_t offset;
 694     ssize_t ret;
 695
 696     if (iovcnt == 1) {
 697         buffer = iov[0].iov_base;
 698         offset = iov[0].iov_len;
 699     } else {
 700         offset = iov_size(iov, iovcnt);
 701         if (offset > NET_BUFSIZE) {
 702             return -1;
 703         }
 704         buf = g_malloc(offset);
 705         buffer = buf;
 706         offset = iov_to_buf(iov, iovcnt, 0, buf, offset);
 707     }
 708
 709     if (flags & QEMU_NET_PACKET_FLAG_RAW && nc->info->receive_raw) {
 710         ret = nc->info->receive_raw(nc, buffer, offset);
 711     } else {
 712         ret = nc->info->receive(nc, buffer, offset);
 713     }
 714
 715     g_free(buf);
 716     return ret;
 717 }
 718
 719 static ssize_t qemu_deliver_packet_iov(NetClientState *sender,
 720                                        unsigned flags,
 721                                        const struct iovec *iov,
 722                                        int iovcnt,
 723                                        void *opaque)
 724 {
 725     NetClientState *nc = opaque;
 726     int ret;
 727
 728
 729     if (nc->link_down) {
 730         return iov_size(iov, iovcnt);
 731     }
 732
 733     if (nc->receive_disabled) {
 734         return 0;
 735     }
 736
 737     if (nc->info->receive_iov && !(flags & QEMU_NET_PACKET_FLAG_RAW)) {
 738         ret = nc->info->receive_iov(nc, iov, iovcnt);
 739     } else {
 740         ret = nc_sendv_compat(nc, iov, iovcnt, flags);
 741     }
 742
 743     if (ret == 0) {
 744         nc->receive_disabled = 1;
 745     }
 746
 747     return ret;
 748 }
 749
 750 ssize_t qemu_sendv_packet_async(NetClientState *sender,
 751                                 const struct iovec *iov, int iovcnt,
 752                                 NetPacketSent *sent_cb)
 753 {
 754     NetQueue *queue;
 755     size_t size = iov_size(iov, iovcnt);
 756     int ret;
 757
 758     if (size > NET_BUFSIZE) {
 759         return size;
 760     }
 761
 762     if (sender->link_down || !sender->peer) {
 763         return size;
 764     }
 765
 766     /* Let filters handle the packet first */
 767     ret = filter_receive_iov(sender, NET_FILTER_DIRECTION_TX, sender,
 768                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
 769     if (ret) {
 770         return ret;
 771     }
 772
 773     ret = filter_receive_iov(sender->peer, NET_FILTER_DIRECTION_RX, sender,
 774                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
 775     if (ret) {
 776         return ret;
 777     }
 778
 779     queue = sender->peer->incoming_queue;
 780
 781     return qemu_net_queue_send_iov(queue, sender,
 782                                    QEMU_NET_PACKET_FLAG_NONE,
 783                                    iov, iovcnt, sent_cb);
 784 }
 785
 786 ssize_t
 787 qemu_sendv_packet(NetClientState *nc, const struct iovec *iov, int iovcnt)
 788 {
 789     return qemu_sendv_packet_async(nc, iov, iovcnt, NULL);
 790 }
 791
 792 NetClientState *qemu_find_netdev(const char *id)
 793 {
 794     NetClientState *nc;
 795
 796     QTAILQ_FOREACH(nc, &net_clients, next) {
 797         if (nc->info->type == NET_CLIENT_DRIVER_NIC)
 798             continue;
 799         if (!strcmp(nc->name, id)) {
 800             return nc;
 801         }
 802     }
 803
 804     return NULL;
 805 }
 806
 807 int qemu_find_net_clients_except(const char *id, NetClientState **ncs,
 808                                  NetClientDriver type, int max)
 809 {
 810     NetClientState *nc;
 811     int ret = 0;
 812
 813     QTAILQ_FOREACH(nc, &net_clients, next) {
 814         if (nc->info->type == type) {
 815             continue;
 816         }
 817         if (!id || !strcmp(nc->name, id)) {
 818             if (ret < max) {
 819                 ncs[ret] = nc;
 820             }
 821             ret++;
 822         }
 823     }
 824
 825     return ret;
 826 }
 827
 828 static int nic_get_free_idx(void)
 829 {
 830     int index;
 831
 832     for (index = 0; index < MAX_NICS; index++)
 833         if (!nd_table[index].used)
 834             return index;
 835     return -1;
 836 }
 837
 838 int qemu_show_nic_models(const char *arg, const char *const *models)
 839 {
 840     int i;
 841
 842     if (!arg || !is_help_option(arg)) {
 843         return 0;
 844     }
 845
 846     printf("Supported NIC models:\n");
 847     for (i = 0 ; models[i]; i++) {
 848         printf("%s\n", models[i]);
 849     }
 850     return 1;
 851 }
 852
 853 void qemu_check_nic_model(NICInfo *nd, const char *model)
 854 {
 855     const char *models[2];
 856
 857     models[0] = model;
 858     models[1] = NULL;
 859
 860     if (qemu_show_nic_models(nd->model, models))
 861         exit(0);
 862     if (qemu_find_nic_model(nd, models, model) < 0)
 863         exit(1);
 864 }
 865
 866 int qemu_find_nic_model(NICInfo *nd, const char * const *models,
 867                         const char *default_model)
 868 {
 869     int i;
 870
 871     if (!nd->model)
 872         nd->model = g_strdup(default_model);
 873
 874     for (i = 0 ; models[i]; i++) {
 875         if (strcmp(nd->model, models[i]) == 0)
 876             return i;
 877     }
 878
 879     error_report("Unsupported NIC model: %s", nd->model);
 880     return -1;
 881 }
 882
 883 static int net_init_nic(const Netdev *netdev, const char *name,
 884                         NetClientState *peer, Error **errp)
 885 {
 886     int idx;
 887     NICInfo *nd;
 888     const NetLegacyNicOptions *nic;
 889
 890     assert(netdev->type == NET_CLIENT_DRIVER_NIC);
 891     nic = &netdev->u.nic;
 892
 893     idx = nic_get_free_idx();
 894     if (idx == -1 || nb_nics >= MAX_NICS) {
 895         error_setg(errp, "too many NICs");
 896         return -1;
 897     }
 898
 899     nd = &nd_table[idx];
 900
 901     memset(nd, 0, sizeof(*nd));
 902
 903     if (nic->has_netdev) {
 904         nd->netdev = qemu_find_netdev(nic->netdev);
 905         if (!nd->netdev) {
 906             error_setg(errp, "netdev '%s' not found", nic->netdev);
 907             return -1;
 908         }
 909     } else {
 910         assert(peer);
 911         nd->netdev = peer;
 912     }
 913     nd->name = g_strdup(name);
 914     if (nic->has_model) {
 915         nd->model = g_strdup(nic->model);
 916     }
 917     if (nic->has_addr) {
 918         nd->devaddr = g_strdup(nic->addr);
 919     }
 920
 921     if (nic->has_macaddr &&
 922         net_parse_macaddr(nd->macaddr.a, nic->macaddr) < 0) {
 923         error_setg(errp, "invalid syntax for ethernet address");
 924         return -1;
 925     }
 926     if (nic->has_macaddr &&
 927         is_multicast_ether_addr(nd->macaddr.a)) {
 928         error_setg(errp,
 929                    "NIC cannot have multicast MAC address (odd 1st byte)");
 930         return -1;
 931     }
 932     qemu_macaddr_default_if_unset(&nd->macaddr);
 933
 934     if (nic->has_vectors) {
 935         if (nic->vectors > 0x7ffffff) {
 936             error_setg(errp, "invalid # of vectors: %"PRIu32, nic->vectors);
 937             return -1;
 938         }
 939         nd->nvectors = nic->vectors;
 940     } else {
 941         nd->nvectors = DEV_NVECTORS_UNSPECIFIED;
 942     }
 943
 944     nd->used = 1;
 945     nb_nics++;
 946
 947     return idx;
 948 }
 949
 950
 951 static int (* const net_client_init_fun[NET_CLIENT_DRIVER__MAX])(
 952     const Netdev *netdev,
 953     const char *name,
 954     NetClientState *peer, Error **errp) = {
 955         [NET_CLIENT_DRIVER_NIC]       = net_init_nic,
 956 #ifdef CONFIG_SLIRP
 957         [NET_CLIENT_DRIVER_USER]      = net_init_slirp,
 958 #endif
 959         [NET_CLIENT_DRIVER_TAP]       = net_init_tap,
 960         [NET_CLIENT_DRIVER_SOCKET]    = net_init_socket,
 961 #ifdef CONFIG_VDE
 962         [NET_CLIENT_DRIVER_VDE]       = net_init_vde,
 963 #endif
 964 #ifdef CONFIG_NETMAP
 965         [NET_CLIENT_DRIVER_NETMAP]    = net_init_netmap,
 966 #endif
 967 #ifdef CONFIG_NET_BRIDGE
 968         [NET_CLIENT_DRIVER_BRIDGE]    = net_init_bridge,
 969 #endif
 970         [NET_CLIENT_DRIVER_HUBPORT]   = net_init_hubport,
 971 #ifdef CONFIG_VHOST_NET_USER
 972         [NET_CLIENT_DRIVER_VHOST_USER] = net_init_vhost_user,
 973 #endif
 974 #ifdef CONFIG_VHOST_NET_VDPA
 975         [NET_CLIENT_DRIVER_VHOST_VDPA] = net_init_vhost_vdpa,
 976 #endif
 977 #ifdef CONFIG_L2TPV3
 978         [NET_CLIENT_DRIVER_L2TPV3]    = net_init_l2tpv3,
 979 #endif
 980 };
 981
 982
 983 static int net_client_init1(const Netdev *netdev, bool is_netdev, Error **errp)
 984 {
 985     NetClientState *peer = NULL;
 986     NetClientState *nc;
 987
 988     if (is_netdev) {
 989         if (netdev->type == NET_CLIENT_DRIVER_NIC ||
 990             !net_client_init_fun[netdev->type]) {
 991             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
 992                        "a netdev backend type");
 993             return -1;
 994         }
 995     } else {
 996         if (netdev->type == NET_CLIENT_DRIVER_NONE) {
 997             return 0; /* nothing to do */
 998         }
 999         if (netdev->type == NET_CLIENT_DRIVER_HUBPORT ||
1000             !net_client_init_fun[netdev->type]) {
1001             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
1002                        "a net backend type (maybe it is not compiled "
1003                        "into this binary)");
1004             return -1;
1005         }
1006
1007         /* Do not add to a hub if it's a nic with a netdev= parameter. */
1008         if (netdev->type != NET_CLIENT_DRIVER_NIC ||
1009             !netdev->u.nic.has_netdev) {
1010             peer = net_hub_add_port(0, NULL, NULL);
1011         }
1012     }
1013
1014     nc = qemu_find_netdev(netdev->id);
1015     if (nc) {
1016         error_setg(errp, "Duplicate ID '%s'", netdev->id);
1017         return -1;
1018     }
1019
1020     if (net_client_init_fun[netdev->type](netdev, netdev->id, peer, errp) < 0) {
1021         /* FIXME drop when all init functions store an Error */
1022         if (errp && !*errp) {
1023             error_setg(errp, "Device '%s' could not be initialized",
1024                        NetClientDriver_str(netdev->type));
1025         }
1026         return -1;
1027     }
1028
1029     if (is_netdev) {
1030         nc = qemu_find_netdev(netdev->id);
1031         assert(nc);
1032         nc->is_netdev = true;
1033     }
1034
1035     return 0;
1036 }
1037
1038 void show_netdevs(void)
1039 {
1040     int idx;
1041     const char *available_netdevs[] = {
1042         "socket",
1043         "hubport",
1044         "tap",
1045 #ifdef CONFIG_SLIRP
1046         "user",
1047 #endif
1048 #ifdef CONFIG_L2TPV3
1049         "l2tpv3",
1050 #endif
1051 #ifdef CONFIG_VDE
1052         "vde",
1053 #endif
1054 #ifdef CONFIG_NET_BRIDGE
1055         "bridge",
1056 #endif
1057 #ifdef CONFIG_NETMAP
1058         "netmap",
1059 #endif
1060 #ifdef CONFIG_POSIX
1061         "vhost-user",
1062 #endif
1063 #ifdef CONFIG_VHOST_VDPA
1064         "vhost-vdpa",
1065 #endif
1066     };
1067
1068     qemu_printf("Available netdev backend types:\n");
1069     for (idx = 0; idx < ARRAY_SIZE(available_netdevs); idx++) {
1070         qemu_printf("%s\n", available_netdevs[idx]);
1071     }
1072 }
1073
1074 static int net_client_init(QemuOpts *opts, bool is_netdev, Error **errp)
1075 {
1076     gchar **substrings = NULL;
1077     Netdev *object = NULL;
1078     int ret = -1;
1079     Visitor *v = opts_visitor_new(opts);
1080
1081     /* Parse convenience option format ip6-net=fec0::0[/64] */
1082     const char *ip6_net = qemu_opt_get(opts, "ipv6-net");
1083
1084     if (ip6_net) {
1085         char *prefix_addr;
1086         unsigned long prefix_len = 64; /* Default 64bit prefix length. */
1087
1088         substrings = g_strsplit(ip6_net, "/", 2);
1089         if (!substrings || !substrings[0]) {
1090             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "ipv6-net",
1091                        "a valid IPv6 prefix");
1092             goto out;
1093         }
1094
1095         prefix_addr = substrings[0];
1096
1097         /* Handle user-specified prefix length. */
1098         if (substrings[1] &&
1099             qemu_strtoul(substrings[1], NULL, 10, &prefix_len))
1100         {
1101             error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1102                        "ipv6-prefixlen", "a number");
1103             goto out;
1104         }
1105
1106         qemu_opt_set(opts, "ipv6-prefix", prefix_addr, &error_abort);
1107         qemu_opt_set_number(opts, "ipv6-prefixlen", prefix_len,
1108                             &error_abort);
1109         qemu_opt_unset(opts, "ipv6-net");
1110     }
1111
1112     /* Create an ID for -net if the user did not specify one */
1113     if (!is_netdev && !qemu_opts_id(opts)) {
1114         qemu_opts_set_id(opts, id_generate(ID_NET));
1115     }
1116
1117     if (visit_type_Netdev(v, NULL, &object, errp)) {
1118         ret = net_client_init1(object, is_netdev, errp);
1119     }
1120
1121     qapi_free_Netdev(object);
1122
1123 out:
1124     g_strfreev(substrings);
1125     visit_free(v);
1126     return ret;
1127 }
1128
1129 void netdev_add(QemuOpts *opts, Error **errp)
1130 {
1131     net_client_init(opts, true, errp);
1132 }
1133
1134 void qmp_netdev_add(Netdev *netdev, Error **errp)
1135 {
1136     net_client_init1(netdev, true, errp);
1137 }
1138
1139 void qmp_netdev_del(const char *id, Error **errp)
1140 {
1141     NetClientState *nc;
1142     QemuOpts *opts;
1143
1144     nc = qemu_find_netdev(id);
1145     if (!nc) {
1146         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1147                   "Device '%s' not found", id);
1148         return;
1149     }
1150
1151     if (!nc->is_netdev) {
1152         error_setg(errp, "Device '%s' is not a netdev", id);
1153         return;
1154     }
1155
1156     qemu_del_net_client(nc);
1157
1158     /*
1159      * Wart: we need to delete the QemuOpts associated with netdevs
1160      * created via CLI or HMP, to avoid bogus "Duplicate ID" errors in
1161      * HMP netdev_add.
1162      */
1163     opts = qemu_opts_find(qemu_find_opts("netdev"), id);
1164     if (opts) {
1165         qemu_opts_del(opts);
1166     }
1167 }
1168
1169 static void netfilter_print_info(Monitor *mon, NetFilterState *nf)
1170 {
1171     char *str;
1172     ObjectProperty *prop;
1173     ObjectPropertyIterator iter;
1174     Visitor *v;
1175
1176     /* generate info str */
1177     object_property_iter_init(&iter, OBJECT(nf));
1178     while ((prop = object_property_iter_next(&iter))) {
1179         if (!strcmp(prop->name, "type")) {
1180             continue;
1181         }
1182         v = string_output_visitor_new(false, &str);
1183         object_property_get(OBJECT(nf), prop->name, v, NULL);
1184         visit_complete(v, &str);
1185         visit_free(v);
1186         monitor_printf(mon, ",%s=%s", prop->name, str);
1187         g_free(str);
1188     }
1189     monitor_printf(mon, "\n");
1190 }
1191
1192 void print_net_client(Monitor *mon, NetClientState *nc)
1193 {
1194     NetFilterState *nf;
1195
1196     monitor_printf(mon, "%s: index=%d,type=%s,%s\n", nc->name,
1197                    nc->queue_index,
1198                    NetClientDriver_str(nc->info->type),
1199                    nc->info_str);
1200     if (!QTAILQ_EMPTY(&nc->filters)) {
1201         monitor_printf(mon, "filters:\n");
1202     }
1203     QTAILQ_FOREACH(nf, &nc->filters, next) {
1204         monitor_printf(mon, "  - %s: type=%s",
1205                        object_get_canonical_path_component(OBJECT(nf)),
1206                        object_get_typename(OBJECT(nf)));
1207         netfilter_print_info(mon, nf);
1208     }
1209 }
1210
1211 RxFilterInfoList *qmp_query_rx_filter(bool has_name, const char *name,
1212                                       Error **errp)
1213 {
1214     NetClientState *nc;
1215     RxFilterInfoList *filter_list = NULL, **tail = &filter_list;
1216
1217     QTAILQ_FOREACH(nc, &net_clients, next) {
1218         RxFilterInfo *info;
1219
1220         if (has_name && strcmp(nc->name, name) != 0) {
1221             continue;
1222         }
1223
1224         /* only query rx-filter information of NIC */
1225         if (nc->info->type != NET_CLIENT_DRIVER_NIC) {
1226             if (has_name) {
1227                 error_setg(errp, "net client(%s) isn't a NIC", name);
1228                 assert(!filter_list);
1229                 return NULL;
1230             }
1231             continue;
1232         }
1233
1234         /* only query information on queue 0 since the info is per nic,
1235          * not per queue
1236          */
1237         if (nc->queue_index != 0)
1238             continue;
1239
1240         if (nc->info->query_rx_filter) {
1241             info = nc->info->query_rx_filter(nc);
1242             QAPI_LIST_APPEND(tail, info);
1243         } else if (has_name) {
1244             error_setg(errp, "net client(%s) doesn't support"
1245                        " rx-filter querying", name);
1246             assert(!filter_list);
1247             return NULL;
1248         }
1249
1250         if (has_name) {
1251             break;
1252         }
1253     }
1254
1255     if (filter_list == NULL && has_name) {
1256         error_setg(errp, "invalid net client name: %s", name);
1257     }
1258
1259     return filter_list;
1260 }
1261
1262 void hmp_info_network(Monitor *mon, const QDict *qdict)
1263 {
1264     NetClientState *nc, *peer;
1265     NetClientDriver type;
1266
1267     net_hub_info(mon);
1268
1269     QTAILQ_FOREACH(nc, &net_clients, next) {
1270         peer = nc->peer;
1271         type = nc->info->type;
1272
1273         /* Skip if already printed in hub info */
1274         if (net_hub_id_for_client(nc, NULL) == 0) {
1275             continue;
1276         }
1277
1278         if (!peer || type == NET_CLIENT_DRIVER_NIC) {
1279             print_net_client(mon, nc);
1280         } /* else it's a netdev connected to a NIC, printed with the NIC */
1281         if (peer && type == NET_CLIENT_DRIVER_NIC) {
1282             monitor_printf(mon, " \\ ");
1283             print_net_client(mon, peer);
1284         }
1285     }
1286 }
1287
1288 void colo_notify_filters_event(int event, Error **errp)
1289 {
1290     NetClientState *nc;
1291     NetFilterState *nf;
1292     NetFilterClass *nfc = NULL;
1293     Error *local_err = NULL;
1294
1295     QTAILQ_FOREACH(nc, &net_clients, next) {
1296         QTAILQ_FOREACH(nf, &nc->filters, next) {
1297             nfc = NETFILTER_GET_CLASS(OBJECT(nf));
1298             nfc->handle_event(nf, event, &local_err);
1299             if (local_err) {
1300                 error_propagate(errp, local_err);
1301                 return;
1302             }
1303         }
1304     }
1305 }
1306
1307 void qmp_set_link(const char *name, bool up, Error **errp)
1308 {
1309     NetClientState *ncs[MAX_QUEUE_NUM];
1310     NetClientState *nc;
1311     int queues, i;
1312
1313     queues = qemu_find_net_clients_except(name, ncs,
1314                                           NET_CLIENT_DRIVER__MAX,
1315                                           MAX_QUEUE_NUM);
1316
1317     if (queues == 0) {
1318         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1319                   "Device '%s' not found", name);
1320         return;
1321     }
1322     nc = ncs[0];
1323
1324     for (i = 0; i < queues; i++) {
1325         ncs[i]->link_down = !up;
1326     }
1327
1328     if (nc->info->link_status_changed) {
1329         nc->info->link_status_changed(nc);
1330     }
1331
1332     if (nc->peer) {
1333         /* Change peer link only if the peer is NIC and then notify peer.
1334          * If the peer is a HUBPORT or a backend, we do not change the
1335          * link status.
1336          *
1337          * This behavior is compatible with qemu hubs where there could be
1338          * multiple clients that can still communicate with each other in
1339          * disconnected mode. For now maintain this compatibility.
1340          */
1341         if (nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
1342             for (i = 0; i < queues; i++) {
1343                 ncs[i]->peer->link_down = !up;
1344             }
1345         }
1346         if (nc->peer->info->link_status_changed) {
1347             nc->peer->info->link_status_changed(nc->peer);
1348         }
1349     }
1350 }
1351
1352 static void net_vm_change_state_handler(void *opaque, bool running,
1353                                         RunState state)
1354 {
1355     NetClientState *nc;
1356     NetClientState *tmp;
1357
1358     QTAILQ_FOREACH_SAFE(nc, &net_clients, next, tmp) {
1359         if (running) {
1360             /* Flush queued packets and wake up backends. */
1361             if (nc->peer && qemu_can_send_packet(nc)) {
1362                 qemu_flush_queued_packets(nc->peer);
1363             }
1364         } else {
1365             /* Complete all queued packets, to guarantee we don't modify
1366              * state later when VM is not running.
1367              */
1368             qemu_flush_or_purge_queued_packets(nc, true);
1369         }
1370     }
1371 }
1372
1373 void net_cleanup(void)
1374 {
1375     NetClientState *nc;
1376
1377     /* We may del multiple entries during qemu_del_net_client(),
1378      * so QTAILQ_FOREACH_SAFE() is also not safe here.
1379      */
1380     while (!QTAILQ_EMPTY(&net_clients)) {
1381         nc = QTAILQ_FIRST(&net_clients);
1382         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
1383             qemu_del_nic(qemu_get_nic(nc));
1384         } else {
1385             qemu_del_net_client(nc);
1386         }
1387     }
1388
1389     qemu_del_vm_change_state_handler(net_change_state_entry);
1390 }
1391
1392 void net_check_clients(void)
1393 {
1394     NetClientState *nc;
1395     int i;
1396
1397     net_hub_check_clients();
1398
1399     QTAILQ_FOREACH(nc, &net_clients, next) {
1400         if (!nc->peer) {
1401             warn_report("%s %s has no peer",
1402                         nc->info->type == NET_CLIENT_DRIVER_NIC
1403                         ? "nic" : "netdev",
1404                         nc->name);
1405         }
1406     }
1407
1408     /* Check that all NICs requested via -net nic actually got created.
1409      * NICs created via -device don't need to be checked here because
1410      * they are always instantiated.
1411      */
1412     for (i = 0; i < MAX_NICS; i++) {
1413         NICInfo *nd = &nd_table[i];
1414         if (nd->used && !nd->instantiated) {
1415             warn_report("requested NIC (%s, model %s) "
1416                         "was not created (not supported by this machine?)",
1417                         nd->name ? nd->name : "anonymous",
1418                         nd->model ? nd->model : "unspecified");
1419         }
1420     }
1421 }
1422
1423 static int net_init_client(void *dummy, QemuOpts *opts, Error **errp)
1424 {
1425     return net_client_init(opts, false, errp);
1426 }
1427
1428 static int net_init_netdev(void *dummy, QemuOpts *opts, Error **errp)
1429 {
1430     const char *type = qemu_opt_get(opts, "type");
1431
1432     if (type && is_help_option(type)) {
1433         show_netdevs();
1434         exit(0);
1435     }
1436     return net_client_init(opts, true, errp);
1437 }
1438
1439 /* For the convenience "--nic" parameter */
1440 static int net_param_nic(void *dummy, QemuOpts *opts, Error **errp)
1441 {
1442     char *mac, *nd_id;
1443     int idx, ret;
1444     NICInfo *ni;
1445     const char *type;
1446
1447     type = qemu_opt_get(opts, "type");
1448     if (type && g_str_equal(type, "none")) {
1449         return 0;    /* Nothing to do, default_net is cleared in vl.c */
1450     }
1451
1452     idx = nic_get_free_idx();
1453     if (idx == -1 || nb_nics >= MAX_NICS) {
1454         error_setg(errp, "no more on-board/default NIC slots available");
1455         return -1;
1456     }
1457
1458     if (!type) {
1459         qemu_opt_set(opts, "type", "user", &error_abort);
1460     }
1461
1462     ni = &nd_table[idx];
1463     memset(ni, 0, sizeof(*ni));
1464     ni->model = qemu_opt_get_del(opts, "model");
1465
1466     /* Create an ID if the user did not specify one */
1467     nd_id = g_strdup(qemu_opts_id(opts));
1468     if (!nd_id) {
1469         nd_id = id_generate(ID_NET);
1470         qemu_opts_set_id(opts, nd_id);
1471     }
1472
1473     /* Handle MAC address */
1474     mac = qemu_opt_get_del(opts, "mac");
1475     if (mac) {
1476         ret = net_parse_macaddr(ni->macaddr.a, mac);
1477         g_free(mac);
1478         if (ret) {
1479             error_setg(errp, "invalid syntax for ethernet address");
1480             goto out;
1481         }
1482         if (is_multicast_ether_addr(ni->macaddr.a)) {
1483             error_setg(errp, "NIC cannot have multicast MAC address");
1484             ret = -1;
1485             goto out;
1486         }
1487     }
1488     qemu_macaddr_default_if_unset(&ni->macaddr);
1489
1490     ret = net_client_init(opts, true, errp);
1491     if (ret == 0) {
1492         ni->netdev = qemu_find_netdev(nd_id);
1493         ni->used = true;
1494         nb_nics++;
1495     }
1496
1497 out:
1498     g_free(nd_id);
1499     return ret;
1500 }
1501
1502 int net_init_clients(Error **errp)
1503 {
1504     net_change_state_entry =
1505         qemu_add_vm_change_state_handler(net_vm_change_state_handler, NULL);
1506
1507     QTAILQ_INIT(&net_clients);
1508
1509     if (qemu_opts_foreach(qemu_find_opts("netdev"),
1510                           net_init_netdev, NULL, errp)) {
1511         return -1;
1512     }
1513
1514     if (qemu_opts_foreach(qemu_find_opts("nic"), net_param_nic, NULL, errp)) {
1515         return -1;
1516     }
1517
1518     if (qemu_opts_foreach(qemu_find_opts("net"), net_init_client, NULL, errp)) {
1519         return -1;
1520     }
1521
1522     return 0;
1523 }
1524
1525 int net_client_parse(QemuOptsList *opts_list, const char *optarg)
1526 {
1527     if (!qemu_opts_parse_noisily(opts_list, optarg, true)) {
1528         return -1;
1529     }
1530
1531     return 0;
1532 }
1533
1534 /* From FreeBSD */
1535 /* XXX: optimize */
1536 uint32_t net_crc32(const uint8_t *p, int len)
1537 {
1538     uint32_t crc;
1539     int carry, i, j;
1540     uint8_t b;
1541
1542     crc = 0xffffffff;
1543     for (i = 0; i < len; i++) {
1544         b = *p++;
1545         for (j = 0; j < 8; j++) {
1546             carry = ((crc & 0x80000000L) ? 1 : 0) ^ (b & 0x01);
1547             crc <<= 1;
1548             b >>= 1;
1549             if (carry) {
1550                 crc = ((crc ^ POLYNOMIAL_BE) | carry);
1551             }
1552         }
1553     }
1554
1555     return crc;
1556 }
1557
1558 uint32_t net_crc32_le(const uint8_t *p, int len)
1559 {
1560     uint32_t crc;
1561     int carry, i, j;
1562     uint8_t b;
1563
1564     crc = 0xffffffff;
1565     for (i = 0; i < len; i++) {
1566         b = *p++;
1567         for (j = 0; j < 8; j++) {
1568             carry = (crc & 0x1) ^ (b & 0x01);
1569             crc >>= 1;
1570             b >>= 1;
1571             if (carry) {
1572                 crc ^= POLYNOMIAL_LE;
1573             }
1574         }
1575     }
1576
1577     return crc;
1578 }
1579
1580 QemuOptsList qemu_netdev_opts = {
1581     .name = "netdev",
1582     .implied_opt_name = "type",
1583     .head = QTAILQ_HEAD_INITIALIZER(qemu_netdev_opts.head),
1584     .desc = {
1585         /*
1586          * no elements => accept any params
1587          * validation will happen later
1588          */
1589         { /* end of list */ }
1590     },
1591 };
1592
1593 QemuOptsList qemu_nic_opts = {
1594     .name = "nic",
1595     .implied_opt_name = "type",
1596     .head = QTAILQ_HEAD_INITIALIZER(qemu_nic_opts.head),
1597     .desc = {
1598         /*
1599          * no elements => accept any params
1600          * validation will happen later
1601          */
1602         { /* end of list */ }
1603     },
1604 };
1605
1606 QemuOptsList qemu_net_opts = {
1607     .name = "net",
1608     .implied_opt_name = "type",
1609     .head = QTAILQ_HEAD_INITIALIZER(qemu_net_opts.head),
1610     .desc = {
1611         /*
1612          * no elements => accept any params
1613          * validation will happen later
1614          */
1615         { /* end of list */ }
1616     },
1617 };
1618
1619 void net_socket_rs_init(SocketReadState *rs,
1620                         SocketReadStateFinalize *finalize,
1621                         bool vnet_hdr)
1622 {
1623     rs->state = 0;
1624     rs->vnet_hdr = vnet_hdr;
1625     rs->index = 0;
1626     rs->packet_len = 0;
1627     rs->vnet_hdr_len = 0;
1628     memset(rs->buf, 0, sizeof(rs->buf));
1629     rs->finalize = finalize;
1630 }
1631
1632 /*
1633  * Returns
1634  * 0: success
1635  * -1: error occurs
1636  */
1637 int net_fill_rstate(SocketReadState *rs, const uint8_t *buf, int size)
1638 {
1639     unsigned int l;
1640
1641     while (size > 0) {
1642         /* Reassemble a packet from the network.
1643          * 0 = getting length.
1644          * 1 = getting vnet header length.
1645          * 2 = getting data.
1646          */
1647         switch (rs->state) {
1648         case 0:
1649             l = 4 - rs->index;
1650             if (l > size) {
1651                 l = size;
1652             }
1653             memcpy(rs->buf + rs->index, buf, l);
1654             buf += l;
1655             size -= l;
1656             rs->index += l;
1657             if (rs->index == 4) {
1658                 /* got length */
1659                 rs->packet_len = ntohl(*(uint32_t *)rs->buf);
1660                 rs->index = 0;
1661                 if (rs->vnet_hdr) {
1662                     rs->state = 1;
1663                 } else {
1664                     rs->state = 2;
1665                     rs->vnet_hdr_len = 0;
1666                 }
1667             }
1668             break;
1669         case 1:
1670             l = 4 - rs->index;
1671             if (l > size) {
1672                 l = size;
1673             }
1674             memcpy(rs->buf + rs->index, buf, l);
1675             buf += l;
1676             size -= l;
1677             rs->index += l;
1678             if (rs->index == 4) {
1679                 /* got vnet header length */
1680                 rs->vnet_hdr_len = ntohl(*(uint32_t *)rs->buf);
1681                 rs->index = 0;
1682                 rs->state = 2;
1683             }
1684             break;
1685         case 2:
1686             l = rs->packet_len - rs->index;
1687             if (l > size) {
1688                 l = size;
1689             }
1690             if (rs->index + l <= sizeof(rs->buf)) {
1691                 memcpy(rs->buf + rs->index, buf, l);
1692             } else {
1693                 fprintf(stderr, "serious error: oversized packet received,"
1694                     "connection terminated.\n");
1695                 rs->index = rs->state = 0;
1696                 return -1;
1697             }
1698
1699             rs->index += l;
1700             buf += l;
1701             size -= l;
1702             if (rs->index >= rs->packet_len) {
1703                 rs->index = 0;
1704                 rs->state = 0;
1705                 assert(rs->finalize);
1706                 rs->finalize(rs);
1707             }
1708             break;
1709         }
1710     }
1711
1712     assert(size == 0);
1713     return 0;
1714 }