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 "qemu/help_option.h"
  36 #include "qapi/qmp/qerror.h"
  37 #include "qemu/error-report.h"
  38 #include "qemu/sockets.h"
  39 #include "qemu/cutils.h"
  40 #include "qemu/config-file.h"
  41 #include "qmp-commands.h"
  42 #include "hw/qdev.h"
  43 #include "qemu/iov.h"
  44 #include "qemu/main-loop.h"
  45 #include "qapi-visit.h"
  46 #include "qapi/opts-visitor.h"
  47 #include "sysemu/sysemu.h"
  48 #include "net/filter.h"
  49 #include "qapi/string-output-visitor.h"
  50
  51 /* Net bridge is currently not supported for W32. */
  52 #if !defined(_WIN32)
  53 # define CONFIG_NET_BRIDGE
  54 #endif
  55
  56 static VMChangeStateEntry *net_change_state_entry;
  57 static QTAILQ_HEAD(, NetClientState) net_clients;
  58
  59 const char *host_net_devices[] = {
  60     "tap",
  61     "socket",
  62     "dump",
  63 #ifdef CONFIG_NET_BRIDGE
  64     "bridge",
  65 #endif
  66 #ifdef CONFIG_NETMAP
  67     "netmap",
  68 #endif
  69 #ifdef CONFIG_SLIRP
  70     "user",
  71 #endif
  72 #ifdef CONFIG_VDE
  73     "vde",
  74 #endif
  75     "vhost-user",
  76     NULL,
  77 };
  78
  79 /***********************************************************/
  80 /* network device redirectors */
  81
  82 static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
  83 {
  84     const char *p, *p1;
  85     int len;
  86     p = *pp;
  87     p1 = strchr(p, sep);
  88     if (!p1)
  89         return -1;
  90     len = p1 - p;
  91     p1++;
  92     if (buf_size > 0) {
  93         if (len > buf_size - 1)
  94             len = buf_size - 1;
  95         memcpy(buf, p, len);
  96         buf[len] = '\0';
  97     }
  98     *pp = p1;
  99     return 0;
 100 }
 101
 102 int parse_host_port(struct sockaddr_in *saddr, const char *str)
 103 {
 104     char buf[512];
 105     struct hostent *he;
 106     const char *p, *r;
 107     int port;
 108
 109     p = str;
 110     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0)
 111         return -1;
 112     saddr->sin_family = AF_INET;
 113     if (buf[0] == '\0') {
 114         saddr->sin_addr.s_addr = 0;
 115     } else {
 116         if (qemu_isdigit(buf[0])) {
 117             if (!inet_aton(buf, &saddr->sin_addr))
 118                 return -1;
 119         } else {
 120             if ((he = gethostbyname(buf)) == NULL)
 121                 return - 1;
 122             saddr->sin_addr = *(struct in_addr *)he->h_addr;
 123         }
 124     }
 125     port = strtol(p, (char **)&r, 0);
 126     if (r == p)
 127         return -1;
 128     saddr->sin_port = htons(port);
 129     return 0;
 130 }
 131
 132 char *qemu_mac_strdup_printf(const uint8_t *macaddr)
 133 {
 134     return g_strdup_printf("%.2x:%.2x:%.2x:%.2x:%.2x:%.2x",
 135                            macaddr[0], macaddr[1], macaddr[2],
 136                            macaddr[3], macaddr[4], macaddr[5]);
 137 }
 138
 139 void qemu_format_nic_info_str(NetClientState *nc, uint8_t macaddr[6])
 140 {
 141     snprintf(nc->info_str, sizeof(nc->info_str),
 142              "model=%s,macaddr=%02x:%02x:%02x:%02x:%02x:%02x",
 143              nc->model,
 144              macaddr[0], macaddr[1], macaddr[2],
 145              macaddr[3], macaddr[4], macaddr[5]);
 146 }
 147
 148 static int mac_table[256] = {0};
 149
 150 static void qemu_macaddr_set_used(MACAddr *macaddr)
 151 {
 152     int index;
 153
 154     for (index = 0x56; index < 0xFF; index++) {
 155         if (macaddr->a[5] == index) {
 156             mac_table[index]++;
 157         }
 158     }
 159 }
 160
 161 static void qemu_macaddr_set_free(MACAddr *macaddr)
 162 {
 163     int index;
 164     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
 165
 166     if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
 167         return;
 168     }
 169     for (index = 0x56; index < 0xFF; index++) {
 170         if (macaddr->a[5] == index) {
 171             mac_table[index]--;
 172         }
 173     }
 174 }
 175
 176 static int qemu_macaddr_get_free(void)
 177 {
 178     int index;
 179
 180     for (index = 0x56; index < 0xFF; index++) {
 181         if (mac_table[index] == 0) {
 182             return index;
 183         }
 184     }
 185
 186     return -1;
 187 }
 188
 189 void qemu_macaddr_default_if_unset(MACAddr *macaddr)
 190 {
 191     static const MACAddr zero = { .a = { 0,0,0,0,0,0 } };
 192     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
 193
 194     if (memcmp(macaddr, &zero, sizeof(zero)) != 0) {
 195         if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
 196             return;
 197         } else {
 198             qemu_macaddr_set_used(macaddr);
 199             return;
 200         }
 201     }
 202
 203     macaddr->a[0] = 0x52;
 204     macaddr->a[1] = 0x54;
 205     macaddr->a[2] = 0x00;
 206     macaddr->a[3] = 0x12;
 207     macaddr->a[4] = 0x34;
 208     macaddr->a[5] = qemu_macaddr_get_free();
 209     qemu_macaddr_set_used(macaddr);
 210 }
 211
 212 /**
 213  * Generate a name for net client
 214  *
 215  * Only net clients created with the legacy -net option and NICs need this.
 216  */
 217 static char *assign_name(NetClientState *nc1, const char *model)
 218 {
 219     NetClientState *nc;
 220     int id = 0;
 221
 222     QTAILQ_FOREACH(nc, &net_clients, next) {
 223         if (nc == nc1) {
 224             continue;
 225         }
 226         if (strcmp(nc->model, model) == 0) {
 227             id++;
 228         }
 229     }
 230
 231     return g_strdup_printf("%s.%d", model, id);
 232 }
 233
 234 static void qemu_net_client_destructor(NetClientState *nc)
 235 {
 236     g_free(nc);
 237 }
 238
 239 static void qemu_net_client_setup(NetClientState *nc,
 240                                   NetClientInfo *info,
 241                                   NetClientState *peer,
 242                                   const char *model,
 243                                   const char *name,
 244                                   NetClientDestructor *destructor)
 245 {
 246     nc->info = info;
 247     nc->model = g_strdup(model);
 248     if (name) {
 249         nc->name = g_strdup(name);
 250     } else {
 251         nc->name = assign_name(nc, model);
 252     }
 253
 254     if (peer) {
 255         assert(!peer->peer);
 256         nc->peer = peer;
 257         peer->peer = nc;
 258     }
 259     QTAILQ_INSERT_TAIL(&net_clients, nc, next);
 260
 261     nc->incoming_queue = qemu_new_net_queue(qemu_deliver_packet_iov, nc);
 262     nc->destructor = destructor;
 263     QTAILQ_INIT(&nc->filters);
 264 }
 265
 266 NetClientState *qemu_new_net_client(NetClientInfo *info,
 267                                     NetClientState *peer,
 268                                     const char *model,
 269                                     const char *name)
 270 {
 271     NetClientState *nc;
 272
 273     assert(info->size >= sizeof(NetClientState));
 274
 275     nc = g_malloc0(info->size);
 276     qemu_net_client_setup(nc, info, peer, model, name,
 277                           qemu_net_client_destructor);
 278
 279     return nc;
 280 }
 281
 282 NICState *qemu_new_nic(NetClientInfo *info,
 283                        NICConf *conf,
 284                        const char *model,
 285                        const char *name,
 286                        void *opaque)
 287 {
 288     NetClientState **peers = conf->peers.ncs;
 289     NICState *nic;
 290     int i, queues = MAX(1, conf->peers.queues);
 291
 292     assert(info->type == NET_CLIENT_DRIVER_NIC);
 293     assert(info->size >= sizeof(NICState));
 294
 295     nic = g_malloc0(info->size + sizeof(NetClientState) * queues);
 296     nic->ncs = (void *)nic + info->size;
 297     nic->conf = conf;
 298     nic->opaque = opaque;
 299
 300     for (i = 0; i < queues; i++) {
 301         qemu_net_client_setup(&nic->ncs[i], info, peers[i], model, name,
 302                               NULL);
 303         nic->ncs[i].queue_index = i;
 304     }
 305
 306     return nic;
 307 }
 308
 309 NetClientState *qemu_get_subqueue(NICState *nic, int queue_index)
 310 {
 311     return nic->ncs + queue_index;
 312 }
 313
 314 NetClientState *qemu_get_queue(NICState *nic)
 315 {
 316     return qemu_get_subqueue(nic, 0);
 317 }
 318
 319 NICState *qemu_get_nic(NetClientState *nc)
 320 {
 321     NetClientState *nc0 = nc - nc->queue_index;
 322
 323     return (NICState *)((void *)nc0 - nc->info->size);
 324 }
 325
 326 void *qemu_get_nic_opaque(NetClientState *nc)
 327 {
 328     NICState *nic = qemu_get_nic(nc);
 329
 330     return nic->opaque;
 331 }
 332
 333 static void qemu_cleanup_net_client(NetClientState *nc)
 334 {
 335     QTAILQ_REMOVE(&net_clients, nc, next);
 336
 337     if (nc->info->cleanup) {
 338         nc->info->cleanup(nc);
 339     }
 340 }
 341
 342 static void qemu_free_net_client(NetClientState *nc)
 343 {
 344     if (nc->incoming_queue) {
 345         qemu_del_net_queue(nc->incoming_queue);
 346     }
 347     if (nc->peer) {
 348         nc->peer->peer = NULL;
 349     }
 350     g_free(nc->name);
 351     g_free(nc->model);
 352     if (nc->destructor) {
 353         nc->destructor(nc);
 354     }
 355 }
 356
 357 void qemu_del_net_client(NetClientState *nc)
 358 {
 359     NetClientState *ncs[MAX_QUEUE_NUM];
 360     int queues, i;
 361     NetFilterState *nf, *next;
 362
 363     assert(nc->info->type != NET_CLIENT_DRIVER_NIC);
 364
 365     /* If the NetClientState belongs to a multiqueue backend, we will change all
 366      * other NetClientStates also.
 367      */
 368     queues = qemu_find_net_clients_except(nc->name, ncs,
 369                                           NET_CLIENT_DRIVER_NIC,
 370                                           MAX_QUEUE_NUM);
 371     assert(queues != 0);
 372
 373     QTAILQ_FOREACH_SAFE(nf, &nc->filters, next, next) {
 374         object_unparent(OBJECT(nf));
 375     }
 376
 377     /* If there is a peer NIC, delete and cleanup client, but do not free. */
 378     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
 379         NICState *nic = qemu_get_nic(nc->peer);
 380         if (nic->peer_deleted) {
 381             return;
 382         }
 383         nic->peer_deleted = true;
 384
 385         for (i = 0; i < queues; i++) {
 386             ncs[i]->peer->link_down = true;
 387         }
 388
 389         if (nc->peer->info->link_status_changed) {
 390             nc->peer->info->link_status_changed(nc->peer);
 391         }
 392
 393         for (i = 0; i < queues; i++) {
 394             qemu_cleanup_net_client(ncs[i]);
 395         }
 396
 397         return;
 398     }
 399
 400     for (i = 0; i < queues; i++) {
 401         qemu_cleanup_net_client(ncs[i]);
 402         qemu_free_net_client(ncs[i]);
 403     }
 404 }
 405
 406 void qemu_del_nic(NICState *nic)
 407 {
 408     int i, queues = MAX(nic->conf->peers.queues, 1);
 409
 410     qemu_macaddr_set_free(&nic->conf->macaddr);
 411
 412     /* If this is a peer NIC and peer has already been deleted, free it now. */
 413     if (nic->peer_deleted) {
 414         for (i = 0; i < queues; i++) {
 415             qemu_free_net_client(qemu_get_subqueue(nic, i)->peer);
 416         }
 417     }
 418
 419     for (i = queues - 1; i >= 0; i--) {
 420         NetClientState *nc = qemu_get_subqueue(nic, i);
 421
 422         qemu_cleanup_net_client(nc);
 423         qemu_free_net_client(nc);
 424     }
 425
 426     g_free(nic);
 427 }
 428
 429 void qemu_foreach_nic(qemu_nic_foreach func, void *opaque)
 430 {
 431     NetClientState *nc;
 432
 433     QTAILQ_FOREACH(nc, &net_clients, next) {
 434         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
 435             if (nc->queue_index == 0) {
 436                 func(qemu_get_nic(nc), opaque);
 437             }
 438         }
 439     }
 440 }
 441
 442 bool qemu_has_ufo(NetClientState *nc)
 443 {
 444     if (!nc || !nc->info->has_ufo) {
 445         return false;
 446     }
 447
 448     return nc->info->has_ufo(nc);
 449 }
 450
 451 bool qemu_has_vnet_hdr(NetClientState *nc)
 452 {
 453     if (!nc || !nc->info->has_vnet_hdr) {
 454         return false;
 455     }
 456
 457     return nc->info->has_vnet_hdr(nc);
 458 }
 459
 460 bool qemu_has_vnet_hdr_len(NetClientState *nc, int len)
 461 {
 462     if (!nc || !nc->info->has_vnet_hdr_len) {
 463         return false;
 464     }
 465
 466     return nc->info->has_vnet_hdr_len(nc, len);
 467 }
 468
 469 void qemu_using_vnet_hdr(NetClientState *nc, bool enable)
 470 {
 471     if (!nc || !nc->info->using_vnet_hdr) {
 472         return;
 473     }
 474
 475     nc->info->using_vnet_hdr(nc, enable);
 476 }
 477
 478 void qemu_set_offload(NetClientState *nc, int csum, int tso4, int tso6,
 479                           int ecn, int ufo)
 480 {
 481     if (!nc || !nc->info->set_offload) {
 482         return;
 483     }
 484
 485     nc->info->set_offload(nc, csum, tso4, tso6, ecn, ufo);
 486 }
 487
 488 void qemu_set_vnet_hdr_len(NetClientState *nc, int len)
 489 {
 490     if (!nc || !nc->info->set_vnet_hdr_len) {
 491         return;
 492     }
 493
 494     nc->info->set_vnet_hdr_len(nc, len);
 495 }
 496
 497 int qemu_set_vnet_le(NetClientState *nc, bool is_le)
 498 {
 499 #ifdef HOST_WORDS_BIGENDIAN
 500     if (!nc || !nc->info->set_vnet_le) {
 501         return -ENOSYS;
 502     }
 503
 504     return nc->info->set_vnet_le(nc, is_le);
 505 #else
 506     return 0;
 507 #endif
 508 }
 509
 510 int qemu_set_vnet_be(NetClientState *nc, bool is_be)
 511 {
 512 #ifdef HOST_WORDS_BIGENDIAN
 513     return 0;
 514 #else
 515     if (!nc || !nc->info->set_vnet_be) {
 516         return -ENOSYS;
 517     }
 518
 519     return nc->info->set_vnet_be(nc, is_be);
 520 #endif
 521 }
 522
 523 int qemu_can_send_packet(NetClientState *sender)
 524 {
 525     int vm_running = runstate_is_running();
 526
 527     if (!vm_running) {
 528         return 0;
 529     }
 530
 531     if (!sender->peer) {
 532         return 1;
 533     }
 534
 535     if (sender->peer->receive_disabled) {
 536         return 0;
 537     } else if (sender->peer->info->can_receive &&
 538                !sender->peer->info->can_receive(sender->peer)) {
 539         return 0;
 540     }
 541     return 1;
 542 }
 543
 544 static ssize_t filter_receive_iov(NetClientState *nc,
 545                                   NetFilterDirection direction,
 546                                   NetClientState *sender,
 547                                   unsigned flags,
 548                                   const struct iovec *iov,
 549                                   int iovcnt,
 550                                   NetPacketSent *sent_cb)
 551 {
 552     ssize_t ret = 0;
 553     NetFilterState *nf = NULL;
 554
 555     if (direction == NET_FILTER_DIRECTION_TX) {
 556         QTAILQ_FOREACH(nf, &nc->filters, next) {
 557             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
 558                                          iovcnt, sent_cb);
 559             if (ret) {
 560                 return ret;
 561             }
 562         }
 563     } else {
 564         QTAILQ_FOREACH_REVERSE(nf, &nc->filters, NetFilterHead, next) {
 565             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
 566                                          iovcnt, sent_cb);
 567             if (ret) {
 568                 return ret;
 569             }
 570         }
 571     }
 572
 573     return ret;
 574 }
 575
 576 static ssize_t filter_receive(NetClientState *nc,
 577                               NetFilterDirection direction,
 578                               NetClientState *sender,
 579                               unsigned flags,
 580                               const uint8_t *data,
 581                               size_t size,
 582                               NetPacketSent *sent_cb)
 583 {
 584     struct iovec iov = {
 585         .iov_base = (void *)data,
 586         .iov_len = size
 587     };
 588
 589     return filter_receive_iov(nc, direction, sender, flags, &iov, 1, sent_cb);
 590 }
 591
 592 void qemu_purge_queued_packets(NetClientState *nc)
 593 {
 594     if (!nc->peer) {
 595         return;
 596     }
 597
 598     qemu_net_queue_purge(nc->peer->incoming_queue, nc);
 599 }
 600
 601 static
 602 void qemu_flush_or_purge_queued_packets(NetClientState *nc, bool purge)
 603 {
 604     nc->receive_disabled = 0;
 605
 606     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_HUBPORT) {
 607         if (net_hub_flush(nc->peer)) {
 608             qemu_notify_event();
 609         }
 610     }
 611     if (qemu_net_queue_flush(nc->incoming_queue)) {
 612         /* We emptied the queue successfully, signal to the IO thread to repoll
 613          * the file descriptor (for tap, for example).
 614          */
 615         qemu_notify_event();
 616     } else if (purge) {
 617         /* Unable to empty the queue, purge remaining packets */
 618         qemu_net_queue_purge(nc->incoming_queue, nc);
 619     }
 620 }
 621
 622 void qemu_flush_queued_packets(NetClientState *nc)
 623 {
 624     qemu_flush_or_purge_queued_packets(nc, false);
 625 }
 626
 627 static ssize_t qemu_send_packet_async_with_flags(NetClientState *sender,
 628                                                  unsigned flags,
 629                                                  const uint8_t *buf, int size,
 630                                                  NetPacketSent *sent_cb)
 631 {
 632     NetQueue *queue;
 633     int ret;
 634
 635 #ifdef DEBUG_NET
 636     printf("qemu_send_packet_async:\n");
 637     qemu_hexdump((const char *)buf, stdout, "net", size);
 638 #endif
 639
 640     if (sender->link_down || !sender->peer) {
 641         return size;
 642     }
 643
 644     /* Let filters handle the packet first */
 645     ret = filter_receive(sender, NET_FILTER_DIRECTION_TX,
 646                          sender, flags, buf, size, sent_cb);
 647     if (ret) {
 648         return ret;
 649     }
 650
 651     ret = filter_receive(sender->peer, NET_FILTER_DIRECTION_RX,
 652                          sender, flags, buf, size, sent_cb);
 653     if (ret) {
 654         return ret;
 655     }
 656
 657     queue = sender->peer->incoming_queue;
 658
 659     return qemu_net_queue_send(queue, sender, flags, buf, size, sent_cb);
 660 }
 661
 662 ssize_t qemu_send_packet_async(NetClientState *sender,
 663                                const uint8_t *buf, int size,
 664                                NetPacketSent *sent_cb)
 665 {
 666     return qemu_send_packet_async_with_flags(sender, QEMU_NET_PACKET_FLAG_NONE,
 667                                              buf, size, sent_cb);
 668 }
 669
 670 void qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size)
 671 {
 672     qemu_send_packet_async(nc, buf, size, NULL);
 673 }
 674
 675 ssize_t qemu_send_packet_raw(NetClientState *nc, const uint8_t *buf, int size)
 676 {
 677     return qemu_send_packet_async_with_flags(nc, QEMU_NET_PACKET_FLAG_RAW,
 678                                              buf, size, NULL);
 679 }
 680
 681 static ssize_t nc_sendv_compat(NetClientState *nc, const struct iovec *iov,
 682                                int iovcnt, unsigned flags)
 683 {
 684     uint8_t *buf = NULL;
 685     uint8_t *buffer;
 686     size_t offset;
 687     ssize_t ret;
 688
 689     if (iovcnt == 1) {
 690         buffer = iov[0].iov_base;
 691         offset = iov[0].iov_len;
 692     } else {
 693         buf = g_new(uint8_t, NET_BUFSIZE);
 694         buffer = buf;
 695         offset = iov_to_buf(iov, iovcnt, 0, buf, NET_BUFSIZE);
 696     }
 697
 698     if (flags & QEMU_NET_PACKET_FLAG_RAW && nc->info->receive_raw) {
 699         ret = nc->info->receive_raw(nc, buffer, offset);
 700     } else {
 701         ret = nc->info->receive(nc, buffer, offset);
 702     }
 703
 704     g_free(buf);
 705     return ret;
 706 }
 707
 708 ssize_t qemu_deliver_packet_iov(NetClientState *sender,
 709                                 unsigned flags,
 710                                 const struct iovec *iov,
 711                                 int iovcnt,
 712                                 void *opaque)
 713 {
 714     NetClientState *nc = opaque;
 715     int ret;
 716
 717     if (nc->link_down) {
 718         return iov_size(iov, iovcnt);
 719     }
 720
 721     if (nc->receive_disabled) {
 722         return 0;
 723     }
 724
 725     if (nc->info->receive_iov && !(flags & QEMU_NET_PACKET_FLAG_RAW)) {
 726         ret = nc->info->receive_iov(nc, iov, iovcnt);
 727     } else {
 728         ret = nc_sendv_compat(nc, iov, iovcnt, flags);
 729     }
 730
 731     if (ret == 0) {
 732         nc->receive_disabled = 1;
 733     }
 734
 735     return ret;
 736 }
 737
 738 ssize_t qemu_sendv_packet_async(NetClientState *sender,
 739                                 const struct iovec *iov, int iovcnt,
 740                                 NetPacketSent *sent_cb)
 741 {
 742     NetQueue *queue;
 743     int ret;
 744
 745     if (sender->link_down || !sender->peer) {
 746         return iov_size(iov, iovcnt);
 747     }
 748
 749     /* Let filters handle the packet first */
 750     ret = filter_receive_iov(sender, NET_FILTER_DIRECTION_TX, sender,
 751                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
 752     if (ret) {
 753         return ret;
 754     }
 755
 756     ret = filter_receive_iov(sender->peer, NET_FILTER_DIRECTION_RX, sender,
 757                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
 758     if (ret) {
 759         return ret;
 760     }
 761
 762     queue = sender->peer->incoming_queue;
 763
 764     return qemu_net_queue_send_iov(queue, sender,
 765                                    QEMU_NET_PACKET_FLAG_NONE,
 766                                    iov, iovcnt, sent_cb);
 767 }
 768
 769 ssize_t
 770 qemu_sendv_packet(NetClientState *nc, const struct iovec *iov, int iovcnt)
 771 {
 772     return qemu_sendv_packet_async(nc, iov, iovcnt, NULL);
 773 }
 774
 775 NetClientState *qemu_find_netdev(const char *id)
 776 {
 777     NetClientState *nc;
 778
 779     QTAILQ_FOREACH(nc, &net_clients, next) {
 780         if (nc->info->type == NET_CLIENT_DRIVER_NIC)
 781             continue;
 782         if (!strcmp(nc->name, id)) {
 783             return nc;
 784         }
 785     }
 786
 787     return NULL;
 788 }
 789
 790 int qemu_find_net_clients_except(const char *id, NetClientState **ncs,
 791                                  NetClientDriver type, int max)
 792 {
 793     NetClientState *nc;
 794     int ret = 0;
 795
 796     QTAILQ_FOREACH(nc, &net_clients, next) {
 797         if (nc->info->type == type) {
 798             continue;
 799         }
 800         if (!id || !strcmp(nc->name, id)) {
 801             if (ret < max) {
 802                 ncs[ret] = nc;
 803             }
 804             ret++;
 805         }
 806     }
 807
 808     return ret;
 809 }
 810
 811 static int nic_get_free_idx(void)
 812 {
 813     int index;
 814
 815     for (index = 0; index < MAX_NICS; index++)
 816         if (!nd_table[index].used)
 817             return index;
 818     return -1;
 819 }
 820
 821 int qemu_show_nic_models(const char *arg, const char *const *models)
 822 {
 823     int i;
 824
 825     if (!arg || !is_help_option(arg)) {
 826         return 0;
 827     }
 828
 829     fprintf(stderr, "qemu: Supported NIC models: ");
 830     for (i = 0 ; models[i]; i++)
 831         fprintf(stderr, "%s%c", models[i], models[i+1] ? ',' : '\n');
 832     return 1;
 833 }
 834
 835 void qemu_check_nic_model(NICInfo *nd, const char *model)
 836 {
 837     const char *models[2];
 838
 839     models[0] = model;
 840     models[1] = NULL;
 841
 842     if (qemu_show_nic_models(nd->model, models))
 843         exit(0);
 844     if (qemu_find_nic_model(nd, models, model) < 0)
 845         exit(1);
 846 }
 847
 848 int qemu_find_nic_model(NICInfo *nd, const char * const *models,
 849                         const char *default_model)
 850 {
 851     int i;
 852
 853     if (!nd->model)
 854         nd->model = g_strdup(default_model);
 855
 856     for (i = 0 ; models[i]; i++) {
 857         if (strcmp(nd->model, models[i]) == 0)
 858             return i;
 859     }
 860
 861     error_report("Unsupported NIC model: %s", nd->model);
 862     return -1;
 863 }
 864
 865 static int net_init_nic(const Netdev *netdev, const char *name,
 866                         NetClientState *peer, Error **errp)
 867 {
 868     int idx;
 869     NICInfo *nd;
 870     const NetLegacyNicOptions *nic;
 871
 872     assert(netdev->type == NET_CLIENT_DRIVER_NIC);
 873     nic = &netdev->u.nic;
 874
 875     idx = nic_get_free_idx();
 876     if (idx == -1 || nb_nics >= MAX_NICS) {
 877         error_setg(errp, "too many NICs");
 878         return -1;
 879     }
 880
 881     nd = &nd_table[idx];
 882
 883     memset(nd, 0, sizeof(*nd));
 884
 885     if (nic->has_netdev) {
 886         nd->netdev = qemu_find_netdev(nic->netdev);
 887         if (!nd->netdev) {
 888             error_setg(errp, "netdev '%s' not found", nic->netdev);
 889             return -1;
 890         }
 891     } else {
 892         assert(peer);
 893         nd->netdev = peer;
 894     }
 895     nd->name = g_strdup(name);
 896     if (nic->has_model) {
 897         nd->model = g_strdup(nic->model);
 898     }
 899     if (nic->has_addr) {
 900         nd->devaddr = g_strdup(nic->addr);
 901     }
 902
 903     if (nic->has_macaddr &&
 904         net_parse_macaddr(nd->macaddr.a, nic->macaddr) < 0) {
 905         error_setg(errp, "invalid syntax for ethernet address");
 906         return -1;
 907     }
 908     if (nic->has_macaddr &&
 909         is_multicast_ether_addr(nd->macaddr.a)) {
 910         error_setg(errp,
 911                    "NIC cannot have multicast MAC address (odd 1st byte)");
 912         return -1;
 913     }
 914     qemu_macaddr_default_if_unset(&nd->macaddr);
 915
 916     if (nic->has_vectors) {
 917         if (nic->vectors > 0x7ffffff) {
 918             error_setg(errp, "invalid # of vectors: %"PRIu32, nic->vectors);
 919             return -1;
 920         }
 921         nd->nvectors = nic->vectors;
 922     } else {
 923         nd->nvectors = DEV_NVECTORS_UNSPECIFIED;
 924     }
 925
 926     nd->used = 1;
 927     nb_nics++;
 928
 929     return idx;
 930 }
 931
 932
 933 static int (* const net_client_init_fun[NET_CLIENT_DRIVER__MAX])(
 934     const Netdev *netdev,
 935     const char *name,
 936     NetClientState *peer, Error **errp) = {
 937         [NET_CLIENT_DRIVER_NIC]       = net_init_nic,
 938 #ifdef CONFIG_SLIRP
 939         [NET_CLIENT_DRIVER_USER]      = net_init_slirp,
 940 #endif
 941         [NET_CLIENT_DRIVER_TAP]       = net_init_tap,
 942         [NET_CLIENT_DRIVER_SOCKET]    = net_init_socket,
 943 #ifdef CONFIG_VDE
 944         [NET_CLIENT_DRIVER_VDE]       = net_init_vde,
 945 #endif
 946 #ifdef CONFIG_NETMAP
 947         [NET_CLIENT_DRIVER_NETMAP]    = net_init_netmap,
 948 #endif
 949         [NET_CLIENT_DRIVER_DUMP]      = net_init_dump,
 950 #ifdef CONFIG_NET_BRIDGE
 951         [NET_CLIENT_DRIVER_BRIDGE]    = net_init_bridge,
 952 #endif
 953         [NET_CLIENT_DRIVER_HUBPORT]   = net_init_hubport,
 954 #ifdef CONFIG_VHOST_NET_USED
 955         [NET_CLIENT_DRIVER_VHOST_USER] = net_init_vhost_user,
 956 #endif
 957 #ifdef CONFIG_L2TPV3
 958         [NET_CLIENT_DRIVER_L2TPV3]    = net_init_l2tpv3,
 959 #endif
 960 };
 961
 962
 963 static int net_client_init1(const void *object, int is_netdev, Error **errp)
 964 {
 965     Netdev legacy = {0};
 966     const Netdev *netdev;
 967     const char *name;
 968     NetClientState *peer = NULL;
 969
 970     if (is_netdev) {
 971         netdev = object;
 972         name = netdev->id;
 973
 974         if (netdev->type == NET_CLIENT_DRIVER_DUMP ||
 975             netdev->type == NET_CLIENT_DRIVER_NIC ||
 976             !net_client_init_fun[netdev->type]) {
 977             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
 978                        "a netdev backend type");
 979             return -1;
 980         }
 981     } else {
 982         const NetLegacy *net = object;
 983         const NetLegacyOptions *opts = net->opts;
 984         legacy.id = net->id;
 985         netdev = &legacy;
 986         /* missing optional values have been initialized to "all bits zero" */
 987         name = net->has_id ? net->id : net->name;
 988
 989         /* Map the old options to the new flat type */
 990         switch (opts->type) {
 991         case NET_LEGACY_OPTIONS_KIND_NONE:
 992             return 0; /* nothing to do */
 993         case NET_LEGACY_OPTIONS_KIND_NIC:
 994             legacy.type = NET_CLIENT_DRIVER_NIC;
 995             legacy.u.nic = *opts->u.nic.data;
 996             break;
 997         case NET_LEGACY_OPTIONS_KIND_USER:
 998             legacy.type = NET_CLIENT_DRIVER_USER;
 999             legacy.u.user = *opts->u.user.data;
1000             break;
1001         case NET_LEGACY_OPTIONS_KIND_TAP:
1002             legacy.type = NET_CLIENT_DRIVER_TAP;
1003             legacy.u.tap = *opts->u.tap.data;
1004             break;
1005         case NET_LEGACY_OPTIONS_KIND_L2TPV3:
1006             legacy.type = NET_CLIENT_DRIVER_L2TPV3;
1007             legacy.u.l2tpv3 = *opts->u.l2tpv3.data;
1008             break;
1009         case NET_LEGACY_OPTIONS_KIND_SOCKET:
1010             legacy.type = NET_CLIENT_DRIVER_SOCKET;
1011             legacy.u.socket = *opts->u.socket.data;
1012             break;
1013         case NET_LEGACY_OPTIONS_KIND_VDE:
1014             legacy.type = NET_CLIENT_DRIVER_VDE;
1015             legacy.u.vde = *opts->u.vde.data;
1016             break;
1017         case NET_LEGACY_OPTIONS_KIND_DUMP:
1018             legacy.type = NET_CLIENT_DRIVER_DUMP;
1019             legacy.u.dump = *opts->u.dump.data;
1020             break;
1021         case NET_LEGACY_OPTIONS_KIND_BRIDGE:
1022             legacy.type = NET_CLIENT_DRIVER_BRIDGE;
1023             legacy.u.bridge = *opts->u.bridge.data;
1024             break;
1025         case NET_LEGACY_OPTIONS_KIND_NETMAP:
1026             legacy.type = NET_CLIENT_DRIVER_NETMAP;
1027             legacy.u.netmap = *opts->u.netmap.data;
1028             break;
1029         case NET_LEGACY_OPTIONS_KIND_VHOST_USER:
1030             legacy.type = NET_CLIENT_DRIVER_VHOST_USER;
1031             legacy.u.vhost_user = *opts->u.vhost_user.data;
1032             break;
1033         default:
1034             abort();
1035         }
1036
1037         if (!net_client_init_fun[netdev->type]) {
1038             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
1039                        "a net backend type (maybe it is not compiled "
1040                        "into this binary)");
1041             return -1;
1042         }
1043
1044         /* Do not add to a vlan if it's a nic with a netdev= parameter. */
1045         if (netdev->type != NET_CLIENT_DRIVER_NIC ||
1046             !opts->u.nic.data->has_netdev) {
1047             peer = net_hub_add_port(net->has_vlan ? net->vlan : 0, NULL);
1048         }
1049     }
1050
1051     if (net_client_init_fun[netdev->type](netdev, name, peer, errp) < 0) {
1052         /* FIXME drop when all init functions store an Error */
1053         if (errp && !*errp) {
1054             error_setg(errp, QERR_DEVICE_INIT_FAILED,
1055                        NetClientDriver_lookup[netdev->type]);
1056         }
1057         return -1;
1058     }
1059     return 0;
1060 }
1061
1062
1063 int net_client_init(QemuOpts *opts, int is_netdev, Error **errp)
1064 {
1065     void *object = NULL;
1066     Error *err = NULL;
1067     int ret = -1;
1068     Visitor *v = opts_visitor_new(opts);
1069
1070     {
1071         /* Parse convenience option format ip6-net=fec0::0[/64] */
1072         const char *ip6_net = qemu_opt_get(opts, "ipv6-net");
1073
1074         if (ip6_net) {
1075             char buf[strlen(ip6_net) + 1];
1076
1077             if (get_str_sep(buf, sizeof(buf), &ip6_net, '/') < 0) {
1078                 /* Default 64bit prefix length.  */
1079                 qemu_opt_set(opts, "ipv6-prefix", ip6_net, &error_abort);
1080                 qemu_opt_set_number(opts, "ipv6-prefixlen", 64, &error_abort);
1081             } else {
1082                 /* User-specified prefix length.  */
1083                 unsigned long len;
1084                 int err;
1085
1086                 qemu_opt_set(opts, "ipv6-prefix", buf, &error_abort);
1087                 err = qemu_strtoul(ip6_net, NULL, 10, &len);
1088
1089                 if (err) {
1090                     error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1091                               "ipv6-prefix", "a number");
1092                 } else {
1093                     qemu_opt_set_number(opts, "ipv6-prefixlen", len,
1094                                         &error_abort);
1095                 }
1096             }
1097             qemu_opt_unset(opts, "ipv6-net");
1098         }
1099     }
1100
1101     if (is_netdev) {
1102         visit_type_Netdev(v, NULL, (Netdev **)&object, &err);
1103     } else {
1104         visit_type_NetLegacy(v, NULL, (NetLegacy **)&object, &err);
1105     }
1106
1107     if (!err) {
1108         ret = net_client_init1(object, is_netdev, &err);
1109     }
1110
1111     if (is_netdev) {
1112         qapi_free_Netdev(object);
1113     } else {
1114         qapi_free_NetLegacy(object);
1115     }
1116
1117     error_propagate(errp, err);
1118     visit_free(v);
1119     return ret;
1120 }
1121
1122
1123 static int net_host_check_device(const char *device)
1124 {
1125     int i;
1126     for (i = 0; host_net_devices[i]; i++) {
1127         if (!strncmp(host_net_devices[i], device,
1128                      strlen(host_net_devices[i]))) {
1129             return 1;
1130         }
1131     }
1132
1133     return 0;
1134 }
1135
1136 void hmp_host_net_add(Monitor *mon, const QDict *qdict)
1137 {
1138     const char *device = qdict_get_str(qdict, "device");
1139     const char *opts_str = qdict_get_try_str(qdict, "opts");
1140     Error *local_err = NULL;
1141     QemuOpts *opts;
1142
1143     if (!net_host_check_device(device)) {
1144         monitor_printf(mon, "invalid host network device %s\n", device);
1145         return;
1146     }
1147
1148     opts = qemu_opts_parse_noisily(qemu_find_opts("net"),
1149                                    opts_str ? opts_str : "", false);
1150     if (!opts) {
1151         return;
1152     }
1153
1154     qemu_opt_set(opts, "type", device, &error_abort);
1155
1156     net_client_init(opts, 0, &local_err);
1157     if (local_err) {
1158         error_report_err(local_err);
1159         monitor_printf(mon, "adding host network device %s failed\n", device);
1160     }
1161 }
1162
1163 void hmp_host_net_remove(Monitor *mon, const QDict *qdict)
1164 {
1165     NetClientState *nc;
1166     int vlan_id = qdict_get_int(qdict, "vlan_id");
1167     const char *device = qdict_get_str(qdict, "device");
1168
1169     nc = net_hub_find_client_by_name(vlan_id, device);
1170     if (!nc) {
1171         error_report("Host network device '%s' on hub '%d' not found",
1172                      device, vlan_id);
1173         return;
1174     }
1175     if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
1176         error_report("invalid host network device '%s'", device);
1177         return;
1178     }
1179
1180     qemu_del_net_client(nc->peer);
1181     qemu_del_net_client(nc);
1182 }
1183
1184 void netdev_add(QemuOpts *opts, Error **errp)
1185 {
1186     net_client_init(opts, 1, errp);
1187 }
1188
1189 void qmp_netdev_add(QDict *qdict, QObject **ret, Error **errp)
1190 {
1191     Error *local_err = NULL;
1192     QemuOptsList *opts_list;
1193     QemuOpts *opts;
1194
1195     opts_list = qemu_find_opts_err("netdev", &local_err);
1196     if (local_err) {
1197         goto out;
1198     }
1199
1200     opts = qemu_opts_from_qdict(opts_list, qdict, &local_err);
1201     if (local_err) {
1202         goto out;
1203     }
1204
1205     netdev_add(opts, &local_err);
1206     if (local_err) {
1207         qemu_opts_del(opts);
1208         goto out;
1209     }
1210
1211 out:
1212     error_propagate(errp, local_err);
1213 }
1214
1215 void qmp_netdev_del(const char *id, Error **errp)
1216 {
1217     NetClientState *nc;
1218     QemuOpts *opts;
1219
1220     nc = qemu_find_netdev(id);
1221     if (!nc) {
1222         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1223                   "Device '%s' not found", id);
1224         return;
1225     }
1226
1227     opts = qemu_opts_find(qemu_find_opts_err("netdev", NULL), id);
1228     if (!opts) {
1229         error_setg(errp, "Device '%s' is not a netdev", id);
1230         return;
1231     }
1232
1233     qemu_del_net_client(nc);
1234     qemu_opts_del(opts);
1235 }
1236
1237 static void netfilter_print_info(Monitor *mon, NetFilterState *nf)
1238 {
1239     char *str;
1240     ObjectProperty *prop;
1241     ObjectPropertyIterator iter;
1242     Visitor *v;
1243
1244     /* generate info str */
1245     object_property_iter_init(&iter, OBJECT(nf));
1246     while ((prop = object_property_iter_next(&iter))) {
1247         if (!strcmp(prop->name, "type")) {
1248             continue;
1249         }
1250         v = string_output_visitor_new(false, &str);
1251         object_property_get(OBJECT(nf), v, prop->name, NULL);
1252         visit_complete(v, &str);
1253         visit_free(v);
1254         monitor_printf(mon, ",%s=%s", prop->name, str);
1255         g_free(str);
1256     }
1257     monitor_printf(mon, "\n");
1258 }
1259
1260 void print_net_client(Monitor *mon, NetClientState *nc)
1261 {
1262     NetFilterState *nf;
1263
1264     monitor_printf(mon, "%s: index=%d,type=%s,%s\n", nc->name,
1265                    nc->queue_index,
1266                    NetClientDriver_lookup[nc->info->type],
1267                    nc->info_str);
1268     if (!QTAILQ_EMPTY(&nc->filters)) {
1269         monitor_printf(mon, "filters:\n");
1270     }
1271     QTAILQ_FOREACH(nf, &nc->filters, next) {
1272         char *path = object_get_canonical_path_component(OBJECT(nf));
1273
1274         monitor_printf(mon, "  - %s: type=%s", path,
1275                        object_get_typename(OBJECT(nf)));
1276         netfilter_print_info(mon, nf);
1277         g_free(path);
1278     }
1279 }
1280
1281 RxFilterInfoList *qmp_query_rx_filter(bool has_name, const char *name,
1282                                       Error **errp)
1283 {
1284     NetClientState *nc;
1285     RxFilterInfoList *filter_list = NULL, *last_entry = NULL;
1286
1287     QTAILQ_FOREACH(nc, &net_clients, next) {
1288         RxFilterInfoList *entry;
1289         RxFilterInfo *info;
1290
1291         if (has_name && strcmp(nc->name, name) != 0) {
1292             continue;
1293         }
1294
1295         /* only query rx-filter information of NIC */
1296         if (nc->info->type != NET_CLIENT_DRIVER_NIC) {
1297             if (has_name) {
1298                 error_setg(errp, "net client(%s) isn't a NIC", name);
1299                 return NULL;
1300             }
1301             continue;
1302         }
1303
1304         /* only query information on queue 0 since the info is per nic,
1305          * not per queue
1306          */
1307         if (nc->queue_index != 0)
1308             continue;
1309
1310         if (nc->info->query_rx_filter) {
1311             info = nc->info->query_rx_filter(nc);
1312             entry = g_malloc0(sizeof(*entry));
1313             entry->value = info;
1314
1315             if (!filter_list) {
1316                 filter_list = entry;
1317             } else {
1318                 last_entry->next = entry;
1319             }
1320             last_entry = entry;
1321         } else if (has_name) {
1322             error_setg(errp, "net client(%s) doesn't support"
1323                        " rx-filter querying", name);
1324             return NULL;
1325         }
1326
1327         if (has_name) {
1328             break;
1329         }
1330     }
1331
1332     if (filter_list == NULL && has_name) {
1333         error_setg(errp, "invalid net client name: %s", name);
1334     }
1335
1336     return filter_list;
1337 }
1338
1339 void hmp_info_network(Monitor *mon, const QDict *qdict)
1340 {
1341     NetClientState *nc, *peer;
1342     NetClientDriver type;
1343
1344     net_hub_info(mon);
1345
1346     QTAILQ_FOREACH(nc, &net_clients, next) {
1347         peer = nc->peer;
1348         type = nc->info->type;
1349
1350         /* Skip if already printed in hub info */
1351         if (net_hub_id_for_client(nc, NULL) == 0) {
1352             continue;
1353         }
1354
1355         if (!peer || type == NET_CLIENT_DRIVER_NIC) {
1356             print_net_client(mon, nc);
1357         } /* else it's a netdev connected to a NIC, printed with the NIC */
1358         if (peer && type == NET_CLIENT_DRIVER_NIC) {
1359             monitor_printf(mon, " \\ ");
1360             print_net_client(mon, peer);
1361         }
1362     }
1363 }
1364
1365 void qmp_set_link(const char *name, bool up, Error **errp)
1366 {
1367     NetClientState *ncs[MAX_QUEUE_NUM];
1368     NetClientState *nc;
1369     int queues, i;
1370
1371     queues = qemu_find_net_clients_except(name, ncs,
1372                                           NET_CLIENT_DRIVER__MAX,
1373                                           MAX_QUEUE_NUM);
1374
1375     if (queues == 0) {
1376         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1377                   "Device '%s' not found", name);
1378         return;
1379     }
1380     nc = ncs[0];
1381
1382     for (i = 0; i < queues; i++) {
1383         ncs[i]->link_down = !up;
1384     }
1385
1386     if (nc->info->link_status_changed) {
1387         nc->info->link_status_changed(nc);
1388     }
1389
1390     if (nc->peer) {
1391         /* Change peer link only if the peer is NIC and then notify peer.
1392          * If the peer is a HUBPORT or a backend, we do not change the
1393          * link status.
1394          *
1395          * This behavior is compatible with qemu vlans where there could be
1396          * multiple clients that can still communicate with each other in
1397          * disconnected mode. For now maintain this compatibility.
1398          */
1399         if (nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
1400             for (i = 0; i < queues; i++) {
1401                 ncs[i]->peer->link_down = !up;
1402             }
1403         }
1404         if (nc->peer->info->link_status_changed) {
1405             nc->peer->info->link_status_changed(nc->peer);
1406         }
1407     }
1408 }
1409
1410 static void net_vm_change_state_handler(void *opaque, int running,
1411                                         RunState state)
1412 {
1413     NetClientState *nc;
1414     NetClientState *tmp;
1415
1416     QTAILQ_FOREACH_SAFE(nc, &net_clients, next, tmp) {
1417         if (running) {
1418             /* Flush queued packets and wake up backends. */
1419             if (nc->peer && qemu_can_send_packet(nc)) {
1420                 qemu_flush_queued_packets(nc->peer);
1421             }
1422         } else {
1423             /* Complete all queued packets, to guarantee we don't modify
1424              * state later when VM is not running.
1425              */
1426             qemu_flush_or_purge_queued_packets(nc, true);
1427         }
1428     }
1429 }
1430
1431 void net_cleanup(void)
1432 {
1433     NetClientState *nc;
1434
1435     /* We may del multiple entries during qemu_del_net_client(),
1436      * so QTAILQ_FOREACH_SAFE() is also not safe here.
1437      */
1438     while (!QTAILQ_EMPTY(&net_clients)) {
1439         nc = QTAILQ_FIRST(&net_clients);
1440         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
1441             qemu_del_nic(qemu_get_nic(nc));
1442         } else {
1443             qemu_del_net_client(nc);
1444         }
1445     }
1446
1447     qemu_del_vm_change_state_handler(net_change_state_entry);
1448 }
1449
1450 void net_check_clients(void)
1451 {
1452     NetClientState *nc;
1453     int i;
1454
1455     net_hub_check_clients();
1456
1457     QTAILQ_FOREACH(nc, &net_clients, next) {
1458         if (!nc->peer) {
1459             fprintf(stderr, "Warning: %s %s has no peer\n",
1460                     nc->info->type == NET_CLIENT_DRIVER_NIC ?
1461                     "nic" : "netdev", nc->name);
1462         }
1463     }
1464
1465     /* Check that all NICs requested via -net nic actually got created.
1466      * NICs created via -device don't need to be checked here because
1467      * they are always instantiated.
1468      */
1469     for (i = 0; i < MAX_NICS; i++) {
1470         NICInfo *nd = &nd_table[i];
1471         if (nd->used && !nd->instantiated) {
1472             fprintf(stderr, "Warning: requested NIC (%s, model %s) "
1473                     "was not created (not supported by this machine?)\n",
1474                     nd->name ? nd->name : "anonymous",
1475                     nd->model ? nd->model : "unspecified");
1476         }
1477     }
1478 }
1479
1480 static int net_init_client(void *dummy, QemuOpts *opts, Error **errp)
1481 {
1482     Error *local_err = NULL;
1483
1484     net_client_init(opts, 0, &local_err);
1485     if (local_err) {
1486         error_report_err(local_err);
1487         return -1;
1488     }
1489
1490     return 0;
1491 }
1492
1493 static int net_init_netdev(void *dummy, QemuOpts *opts, Error **errp)
1494 {
1495     Error *local_err = NULL;
1496     int ret;
1497
1498     ret = net_client_init(opts, 1, &local_err);
1499     if (local_err) {
1500         error_report_err(local_err);
1501         return -1;
1502     }
1503
1504     return ret;
1505 }
1506
1507 int net_init_clients(void)
1508 {
1509     QemuOptsList *net = qemu_find_opts("net");
1510
1511     net_change_state_entry =
1512         qemu_add_vm_change_state_handler(net_vm_change_state_handler, NULL);
1513
1514     QTAILQ_INIT(&net_clients);
1515
1516     if (qemu_opts_foreach(qemu_find_opts("netdev"),
1517                           net_init_netdev, NULL, NULL)) {
1518         return -1;
1519     }
1520
1521     if (qemu_opts_foreach(net, net_init_client, NULL, NULL)) {
1522         return -1;
1523     }
1524
1525     return 0;
1526 }
1527
1528 int net_client_parse(QemuOptsList *opts_list, const char *optarg)
1529 {
1530 #if defined(CONFIG_SLIRP)
1531     int ret;
1532     if (net_slirp_parse_legacy(opts_list, optarg, &ret)) {
1533         return ret;
1534     }
1535 #endif
1536
1537     if (!qemu_opts_parse_noisily(opts_list, optarg, true)) {
1538         return -1;
1539     }
1540
1541     return 0;
1542 }
1543
1544 /* From FreeBSD */
1545 /* XXX: optimize */
1546 unsigned compute_mcast_idx(const uint8_t *ep)
1547 {
1548     uint32_t crc;
1549     int carry, i, j;
1550     uint8_t b;
1551
1552     crc = 0xffffffff;
1553     for (i = 0; i < 6; i++) {
1554         b = *ep++;
1555         for (j = 0; j < 8; j++) {
1556             carry = ((crc & 0x80000000L) ? 1 : 0) ^ (b & 0x01);
1557             crc <<= 1;
1558             b >>= 1;
1559             if (carry) {
1560                 crc = ((crc ^ POLYNOMIAL) | carry);
1561             }
1562         }
1563     }
1564     return crc >> 26;
1565 }
1566
1567 QemuOptsList qemu_netdev_opts = {
1568     .name = "netdev",
1569     .implied_opt_name = "type",
1570     .head = QTAILQ_HEAD_INITIALIZER(qemu_netdev_opts.head),
1571     .desc = {
1572         /*
1573          * no elements => accept any params
1574          * validation will happen later
1575          */
1576         { /* end of list */ }
1577     },
1578 };
1579
1580 QemuOptsList qemu_net_opts = {
1581     .name = "net",
1582     .implied_opt_name = "type",
1583     .head = QTAILQ_HEAD_INITIALIZER(qemu_net_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 void net_socket_rs_init(SocketReadState *rs,
1594                         SocketReadStateFinalize *finalize)
1595 {
1596     rs->state = 0;
1597     rs->index = 0;
1598     rs->packet_len = 0;
1599     memset(rs->buf, 0, sizeof(rs->buf));
1600     rs->finalize = finalize;
1601 }
1602
1603 /*
1604  * Returns
1605  * 0: SocketReadState is not ready
1606  * 1: SocketReadState is ready
1607  * otherwise error occurs
1608  */
1609 int net_fill_rstate(SocketReadState *rs, const uint8_t *buf, int size)
1610 {
1611     unsigned int l;
1612
1613     while (size > 0) {
1614         /* reassemble a packet from the network */
1615         switch (rs->state) { /* 0 = getting length, 1 = getting data */
1616         case 0:
1617             l = 4 - rs->index;
1618             if (l > size) {
1619                 l = size;
1620             }
1621             memcpy(rs->buf + rs->index, buf, l);
1622             buf += l;
1623             size -= l;
1624             rs->index += l;
1625             if (rs->index == 4) {
1626                 /* got length */
1627                 rs->packet_len = ntohl(*(uint32_t *)rs->buf);
1628                 rs->index = 0;
1629                 rs->state = 1;
1630             }
1631             break;
1632         case 1:
1633             l = rs->packet_len - rs->index;
1634             if (l > size) {
1635                 l = size;
1636             }
1637             if (rs->index + l <= sizeof(rs->buf)) {
1638                 memcpy(rs->buf + rs->index, buf, l);
1639             } else {
1640                 fprintf(stderr, "serious error: oversized packet received,"
1641                     "connection terminated.\n");
1642                 rs->index = rs->state = 0;
1643                 return -1;
1644             }
1645
1646             rs->index += l;
1647             buf += l;
1648             size -= l;
1649             if (rs->index >= rs->packet_len) {
1650                 rs->index = 0;
1651                 rs->state = 0;
1652                 if (rs->finalize) {
1653                     rs->finalize(rs);
1654                 }
1655                 return 1;
1656             }
1657             break;
1658         }
1659     }
1660     return 0;
1661 }