net/socket.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 "monitor/monitor.h"
  29 #include "qapi/error.h"
  30 #include "qemu-common.h"
  31 #include "qemu/error-report.h"
  32 #include "qemu/option.h"
  33 #include "qemu/sockets.h"
  34 #include "qemu/iov.h"
  35 #include "qemu/main-loop.h"
  36
  37 typedef struct NetSocketState {
  38     NetClientState nc;
  39     int listen_fd;
  40     int fd;
  41     SocketReadState rs;
  42     unsigned int send_index;      /* number of bytes sent (only SOCK_STREAM) */
  43     struct sockaddr_in dgram_dst; /* contains inet host and port destination iff connectionless (SOCK_DGRAM) */
  44     IOHandler *send_fn;           /* differs between SOCK_STREAM/SOCK_DGRAM */
  45     bool read_poll;               /* waiting to receive data? */
  46     bool write_poll;              /* waiting to transmit data? */
  47 } NetSocketState;
  48
  49 static void net_socket_accept(void *opaque);
  50 static void net_socket_writable(void *opaque);
  51
  52 static void net_socket_update_fd_handler(NetSocketState *s)
  53 {
  54     qemu_set_fd_handler(s->fd,
  55                         s->read_poll ? s->send_fn : NULL,
  56                         s->write_poll ? net_socket_writable : NULL,
  57                         s);
  58 }
  59
  60 static void net_socket_read_poll(NetSocketState *s, bool enable)
  61 {
  62     s->read_poll = enable;
  63     net_socket_update_fd_handler(s);
  64 }
  65
  66 static void net_socket_write_poll(NetSocketState *s, bool enable)
  67 {
  68     s->write_poll = enable;
  69     net_socket_update_fd_handler(s);
  70 }
  71
  72 static void net_socket_writable(void *opaque)
  73 {
  74     NetSocketState *s = opaque;
  75
  76     net_socket_write_poll(s, false);
  77
  78     qemu_flush_queued_packets(&s->nc);
  79 }
  80
  81 static ssize_t net_socket_receive(NetClientState *nc, const uint8_t *buf, size_t size)
  82 {
  83     NetSocketState *s = DO_UPCAST(NetSocketState, nc, nc);
  84     uint32_t len = htonl(size);
  85     struct iovec iov[] = {
  86         {
  87             .iov_base = &len,
  88             .iov_len  = sizeof(len),
  89         }, {
  90             .iov_base = (void *)buf,
  91             .iov_len  = size,
  92         },
  93     };
  94     size_t remaining;
  95     ssize_t ret;
  96
  97     remaining = iov_size(iov, 2) - s->send_index;
  98     ret = iov_send(s->fd, iov, 2, s->send_index, remaining);
  99
 100     if (ret == -1 && errno == EAGAIN) {
 101         ret = 0; /* handled further down */
 102     }
 103     if (ret == -1) {
 104         s->send_index = 0;
 105         return -errno;
 106     }
 107     if (ret < (ssize_t)remaining) {
 108         s->send_index += ret;
 109         net_socket_write_poll(s, true);
 110         return 0;
 111     }
 112     s->send_index = 0;
 113     return size;
 114 }
 115
 116 static ssize_t net_socket_receive_dgram(NetClientState *nc, const uint8_t *buf, size_t size)
 117 {
 118     NetSocketState *s = DO_UPCAST(NetSocketState, nc, nc);
 119     ssize_t ret;
 120
 121     do {
 122         if (s->dgram_dst.sin_family != AF_UNIX) {
 123             ret = qemu_sendto(s->fd, buf, size, 0,
 124                               (struct sockaddr *)&s->dgram_dst,
 125                               sizeof(s->dgram_dst));
 126         } else {
 127             ret = send(s->fd, buf, size, 0);
 128         }
 129     } while (ret == -1 && errno == EINTR);
 130
 131     if (ret == -1 && errno == EAGAIN) {
 132         net_socket_write_poll(s, true);
 133         return 0;
 134     }
 135     return ret;
 136 }
 137
 138 static void net_socket_send_completed(NetClientState *nc, ssize_t len)
 139 {
 140     NetSocketState *s = DO_UPCAST(NetSocketState, nc, nc);
 141
 142     if (!s->read_poll) {
 143         net_socket_read_poll(s, true);
 144     }
 145 }
 146
 147 static void net_socket_rs_finalize(SocketReadState *rs)
 148 {
 149     NetSocketState *s = container_of(rs, NetSocketState, rs);
 150
 151     if (qemu_send_packet_async(&s->nc, rs->buf,
 152                                rs->packet_len,
 153                                net_socket_send_completed) == 0) {
 154         net_socket_read_poll(s, false);
 155     }
 156 }
 157
 158 static void net_socket_send(void *opaque)
 159 {
 160     NetSocketState *s = opaque;
 161     int size;
 162     int ret;
 163     uint8_t buf1[NET_BUFSIZE];
 164     const uint8_t *buf;
 165
 166     size = qemu_recv(s->fd, buf1, sizeof(buf1), 0);
 167     if (size < 0) {
 168         if (errno != EWOULDBLOCK)
 169             goto eoc;
 170     } else if (size == 0) {
 171         /* end of connection */
 172     eoc:
 173         net_socket_read_poll(s, false);
 174         net_socket_write_poll(s, false);
 175         if (s->listen_fd != -1) {
 176             qemu_set_fd_handler(s->listen_fd, net_socket_accept, NULL, s);
 177         }
 178         closesocket(s->fd);
 179
 180         s->fd = -1;
 181         net_socket_rs_init(&s->rs, net_socket_rs_finalize, false);
 182         s->nc.link_down = true;
 183         memset(s->nc.info_str, 0, sizeof(s->nc.info_str));
 184
 185         return;
 186     }
 187     buf = buf1;
 188
 189     ret = net_fill_rstate(&s->rs, buf, size);
 190
 191     if (ret == -1) {
 192         goto eoc;
 193     }
 194 }
 195
 196 static void net_socket_send_dgram(void *opaque)
 197 {
 198     NetSocketState *s = opaque;
 199     int size;
 200
 201     size = qemu_recv(s->fd, s->rs.buf, sizeof(s->rs.buf), 0);
 202     if (size < 0)
 203         return;
 204     if (size == 0) {
 205         /* end of connection */
 206         net_socket_read_poll(s, false);
 207         net_socket_write_poll(s, false);
 208         return;
 209     }
 210     if (qemu_send_packet_async(&s->nc, s->rs.buf, size,
 211                                net_socket_send_completed) == 0) {
 212         net_socket_read_poll(s, false);
 213     }
 214 }
 215
 216 static int net_socket_mcast_create(struct sockaddr_in *mcastaddr,
 217                                    struct in_addr *localaddr,
 218                                    Error **errp)
 219 {
 220     struct ip_mreq imr;
 221     int fd;
 222     int val, ret;
 223 #ifdef __OpenBSD__
 224     unsigned char loop;
 225 #else
 226     int loop;
 227 #endif
 228
 229     if (!IN_MULTICAST(ntohl(mcastaddr->sin_addr.s_addr))) {
 230         error_setg(errp, "specified mcastaddr %s (0x%08x) "
 231                    "does not contain a multicast address",
 232                    inet_ntoa(mcastaddr->sin_addr),
 233                    (int)ntohl(mcastaddr->sin_addr.s_addr));
 234         return -1;
 235     }
 236
 237     fd = qemu_socket(PF_INET, SOCK_DGRAM, 0);
 238     if (fd < 0) {
 239         error_setg_errno(errp, errno, "can't create datagram socket");
 240         return -1;
 241     }
 242
 243     /* Allow multiple sockets to bind the same multicast ip and port by setting
 244      * SO_REUSEADDR. This is the only situation where SO_REUSEADDR should be set
 245      * on windows. Use socket_set_fast_reuse otherwise as it sets SO_REUSEADDR
 246      * only on posix systems.
 247      */
 248     val = 1;
 249     ret = qemu_setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
 250     if (ret < 0) {
 251         error_setg_errno(errp, errno,
 252                          "can't set socket option SO_REUSEADDR");
 253         goto fail;
 254     }
 255
 256     ret = bind(fd, (struct sockaddr *)mcastaddr, sizeof(*mcastaddr));
 257     if (ret < 0) {
 258         error_setg_errno(errp, errno, "can't bind ip=%s to socket",
 259                          inet_ntoa(mcastaddr->sin_addr));
 260         goto fail;
 261     }
 262
 263     /* Add host to multicast group */
 264     imr.imr_multiaddr = mcastaddr->sin_addr;
 265     if (localaddr) {
 266         imr.imr_interface = *localaddr;
 267     } else {
 268         imr.imr_interface.s_addr = htonl(INADDR_ANY);
 269     }
 270
 271     ret = qemu_setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
 272                           &imr, sizeof(struct ip_mreq));
 273     if (ret < 0) {
 274         error_setg_errno(errp, errno,
 275                          "can't add socket to multicast group %s",
 276                          inet_ntoa(imr.imr_multiaddr));
 277         goto fail;
 278     }
 279
 280     /* Force mcast msgs to loopback (eg. several QEMUs in same host */
 281     loop = 1;
 282     ret = qemu_setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP,
 283                           &loop, sizeof(loop));
 284     if (ret < 0) {
 285         error_setg_errno(errp, errno,
 286                          "can't force multicast message to loopback");
 287         goto fail;
 288     }
 289
 290     /* If a bind address is given, only send packets from that address */
 291     if (localaddr != NULL) {
 292         ret = qemu_setsockopt(fd, IPPROTO_IP, IP_MULTICAST_IF,
 293                               localaddr, sizeof(*localaddr));
 294         if (ret < 0) {
 295             error_setg_errno(errp, errno,
 296                              "can't set the default network send interface");
 297             goto fail;
 298         }
 299     }
 300
 301     qemu_set_nonblock(fd);
 302     return fd;
 303 fail:
 304     if (fd >= 0)
 305         closesocket(fd);
 306     return -1;
 307 }
 308
 309 static void net_socket_cleanup(NetClientState *nc)
 310 {
 311     NetSocketState *s = DO_UPCAST(NetSocketState, nc, nc);
 312     if (s->fd != -1) {
 313         net_socket_read_poll(s, false);
 314         net_socket_write_poll(s, false);
 315         close(s->fd);
 316         s->fd = -1;
 317     }
 318     if (s->listen_fd != -1) {
 319         qemu_set_fd_handler(s->listen_fd, NULL, NULL, NULL);
 320         closesocket(s->listen_fd);
 321         s->listen_fd = -1;
 322     }
 323 }
 324
 325 static NetClientInfo net_dgram_socket_info = {
 326     .type = NET_CLIENT_DRIVER_SOCKET,
 327     .size = sizeof(NetSocketState),
 328     .receive = net_socket_receive_dgram,
 329     .cleanup = net_socket_cleanup,
 330 };
 331
 332 static NetSocketState *net_socket_fd_init_dgram(NetClientState *peer,
 333                                                 const char *model,
 334                                                 const char *name,
 335                                                 int fd, int is_connected,
 336                                                 const char *mcast,
 337                                                 Error **errp)
 338 {
 339     struct sockaddr_in saddr;
 340     int newfd;
 341     NetClientState *nc;
 342     NetSocketState *s;
 343     SocketAddress *sa;
 344     SocketAddressType sa_type;
 345
 346     sa = socket_local_address(fd, errp);
 347     if (!sa) {
 348         return NULL;
 349     }
 350     sa_type = sa->type;
 351     qapi_free_SocketAddress(sa);
 352
 353     /* fd passed: multicast: "learn" dgram_dst address from bound address and save it
 354      * Because this may be "shared" socket from a "master" process, datagrams would be recv()
 355      * by ONLY ONE process: we must "clone" this dgram socket --jjo
 356      */
 357
 358     if (is_connected && mcast != NULL) {
 359             if (parse_host_port(&saddr, mcast, errp) < 0) {
 360                 goto err;
 361             }
 362             /* must be bound */
 363             if (saddr.sin_addr.s_addr == 0) {
 364                 error_setg(errp, "can't setup multicast destination address");
 365                 goto err;
 366             }
 367             /* clone dgram socket */
 368             newfd = net_socket_mcast_create(&saddr, NULL, errp);
 369             if (newfd < 0) {
 370                 goto err;
 371             }
 372             /* clone newfd to fd, close newfd */
 373             dup2(newfd, fd);
 374             close(newfd);
 375
 376     }
 377
 378     nc = qemu_new_net_client(&net_dgram_socket_info, peer, model, name);
 379
 380     s = DO_UPCAST(NetSocketState, nc, nc);
 381
 382     s->fd = fd;
 383     s->listen_fd = -1;
 384     s->send_fn = net_socket_send_dgram;
 385     net_socket_rs_init(&s->rs, net_socket_rs_finalize, false);
 386     net_socket_read_poll(s, true);
 387
 388     /* mcast: save bound address as dst */
 389     if (is_connected && mcast != NULL) {
 390         s->dgram_dst = saddr;
 391         snprintf(nc->info_str, sizeof(nc->info_str),
 392                  "socket: fd=%d (cloned mcast=%s:%d)",
 393                  fd, inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
 394     } else {
 395         if (sa_type == SOCKET_ADDRESS_TYPE_UNIX) {
 396             s->dgram_dst.sin_family = AF_UNIX;
 397         }
 398
 399         snprintf(nc->info_str, sizeof(nc->info_str),
 400                  "socket: fd=%d %s", fd, SocketAddressType_str(sa_type));
 401     }
 402
 403     return s;
 404
 405 err:
 406     closesocket(fd);
 407     return NULL;
 408 }
 409
 410 static void net_socket_connect(void *opaque)
 411 {
 412     NetSocketState *s = opaque;
 413     s->send_fn = net_socket_send;
 414     net_socket_read_poll(s, true);
 415 }
 416
 417 static NetClientInfo net_socket_info = {
 418     .type = NET_CLIENT_DRIVER_SOCKET,
 419     .size = sizeof(NetSocketState),
 420     .receive = net_socket_receive,
 421     .cleanup = net_socket_cleanup,
 422 };
 423
 424 static NetSocketState *net_socket_fd_init_stream(NetClientState *peer,
 425                                                  const char *model,
 426                                                  const char *name,
 427                                                  int fd, int is_connected)
 428 {
 429     NetClientState *nc;
 430     NetSocketState *s;
 431
 432     nc = qemu_new_net_client(&net_socket_info, peer, model, name);
 433
 434     snprintf(nc->info_str, sizeof(nc->info_str), "socket: fd=%d", fd);
 435
 436     s = DO_UPCAST(NetSocketState, nc, nc);
 437
 438     s->fd = fd;
 439     s->listen_fd = -1;
 440     net_socket_rs_init(&s->rs, net_socket_rs_finalize, false);
 441
 442     /* Disable Nagle algorithm on TCP sockets to reduce latency */
 443     socket_set_nodelay(fd);
 444
 445     if (is_connected) {
 446         net_socket_connect(s);
 447     } else {
 448         qemu_set_fd_handler(s->fd, NULL, net_socket_connect, s);
 449     }
 450     return s;
 451 }
 452
 453 static NetSocketState *net_socket_fd_init(NetClientState *peer,
 454                                           const char *model, const char *name,
 455                                           int fd, int is_connected,
 456                                           const char *mc, Error **errp)
 457 {
 458     int so_type = -1, optlen=sizeof(so_type);
 459
 460     if(getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&so_type,
 461         (socklen_t *)&optlen)< 0) {
 462         error_setg(errp, "can't get socket option SO_TYPE");
 463         closesocket(fd);
 464         return NULL;
 465     }
 466     switch(so_type) {
 467     case SOCK_DGRAM:
 468         return net_socket_fd_init_dgram(peer, model, name, fd, is_connected,
 469                                         mc, errp);
 470     case SOCK_STREAM:
 471         return net_socket_fd_init_stream(peer, model, name, fd, is_connected);
 472     default:
 473         error_setg(errp, "socket type=%d for fd=%d must be either"
 474                    " SOCK_DGRAM or SOCK_STREAM", so_type, fd);
 475         closesocket(fd);
 476     }
 477     return NULL;
 478 }
 479
 480 static void net_socket_accept(void *opaque)
 481 {
 482     NetSocketState *s = opaque;
 483     struct sockaddr_in saddr;
 484     socklen_t len;
 485     int fd;
 486
 487     for(;;) {
 488         len = sizeof(saddr);
 489         fd = qemu_accept(s->listen_fd, (struct sockaddr *)&saddr, &len);
 490         if (fd < 0 && errno != EINTR) {
 491             return;
 492         } else if (fd >= 0) {
 493             qemu_set_fd_handler(s->listen_fd, NULL, NULL, NULL);
 494             break;
 495         }
 496     }
 497
 498     s->fd = fd;
 499     s->nc.link_down = false;
 500     net_socket_connect(s);
 501     snprintf(s->nc.info_str, sizeof(s->nc.info_str),
 502              "socket: connection from %s:%d",
 503              inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
 504 }
 505
 506 static int net_socket_listen_init(NetClientState *peer,
 507                                   const char *model,
 508                                   const char *name,
 509                                   const char *host_str,
 510                                   Error **errp)
 511 {
 512     NetClientState *nc;
 513     NetSocketState *s;
 514     struct sockaddr_in saddr;
 515     int fd, ret;
 516
 517     if (parse_host_port(&saddr, host_str, errp) < 0) {
 518         return -1;
 519     }
 520
 521     fd = qemu_socket(PF_INET, SOCK_STREAM, 0);
 522     if (fd < 0) {
 523         error_setg_errno(errp, errno, "can't create stream socket");
 524         return -1;
 525     }
 526     qemu_set_nonblock(fd);
 527
 528     socket_set_fast_reuse(fd);
 529
 530     ret = bind(fd, (struct sockaddr *)&saddr, sizeof(saddr));
 531     if (ret < 0) {
 532         error_setg_errno(errp, errno, "can't bind ip=%s to socket",
 533                          inet_ntoa(saddr.sin_addr));
 534         closesocket(fd);
 535         return -1;
 536     }
 537     ret = listen(fd, 0);
 538     if (ret < 0) {
 539         error_setg_errno(errp, errno, "can't listen on socket");
 540         closesocket(fd);
 541         return -1;
 542     }
 543
 544     nc = qemu_new_net_client(&net_socket_info, peer, model, name);
 545     s = DO_UPCAST(NetSocketState, nc, nc);
 546     s->fd = -1;
 547     s->listen_fd = fd;
 548     s->nc.link_down = true;
 549     net_socket_rs_init(&s->rs, net_socket_rs_finalize, false);
 550
 551     qemu_set_fd_handler(s->listen_fd, net_socket_accept, NULL, s);
 552     return 0;
 553 }
 554
 555 static int net_socket_connect_init(NetClientState *peer,
 556                                    const char *model,
 557                                    const char *name,
 558                                    const char *host_str,
 559                                    Error **errp)
 560 {
 561     NetSocketState *s;
 562     int fd, connected, ret;
 563     struct sockaddr_in saddr;
 564
 565     if (parse_host_port(&saddr, host_str, errp) < 0) {
 566         return -1;
 567     }
 568
 569     fd = qemu_socket(PF_INET, SOCK_STREAM, 0);
 570     if (fd < 0) {
 571         error_setg_errno(errp, errno, "can't create stream socket");
 572         return -1;
 573     }
 574     qemu_set_nonblock(fd);
 575
 576     connected = 0;
 577     for(;;) {
 578         ret = connect(fd, (struct sockaddr *)&saddr, sizeof(saddr));
 579         if (ret < 0) {
 580             if (errno == EINTR || errno == EWOULDBLOCK) {
 581                 /* continue */
 582             } else if (errno == EINPROGRESS ||
 583                        errno == EALREADY ||
 584                        errno == EINVAL) {
 585                 break;
 586             } else {
 587                 error_setg_errno(errp, errno, "can't connect socket");
 588                 closesocket(fd);
 589                 return -1;
 590             }
 591         } else {
 592             connected = 1;
 593             break;
 594         }
 595     }
 596     s = net_socket_fd_init(peer, model, name, fd, connected, NULL, errp);
 597     if (!s) {
 598         return -1;
 599     }
 600
 601     snprintf(s->nc.info_str, sizeof(s->nc.info_str),
 602              "socket: connect to %s:%d",
 603              inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
 604     return 0;
 605 }
 606
 607 static int net_socket_mcast_init(NetClientState *peer,
 608                                  const char *model,
 609                                  const char *name,
 610                                  const char *host_str,
 611                                  const char *localaddr_str,
 612                                  Error **errp)
 613 {
 614     NetSocketState *s;
 615     int fd;
 616     struct sockaddr_in saddr;
 617     struct in_addr localaddr, *param_localaddr;
 618
 619     if (parse_host_port(&saddr, host_str, errp) < 0) {
 620         return -1;
 621     }
 622
 623     if (localaddr_str != NULL) {
 624         if (inet_aton(localaddr_str, &localaddr) == 0) {
 625             error_setg(errp, "localaddr '%s' is not a valid IPv4 address",
 626                        localaddr_str);
 627             return -1;
 628         }
 629         param_localaddr = &localaddr;
 630     } else {
 631         param_localaddr = NULL;
 632     }
 633
 634     fd = net_socket_mcast_create(&saddr, param_localaddr, errp);
 635     if (fd < 0) {
 636         return -1;
 637     }
 638
 639     s = net_socket_fd_init(peer, model, name, fd, 0, NULL, errp);
 640     if (!s) {
 641         return -1;
 642     }
 643
 644     s->dgram_dst = saddr;
 645
 646     snprintf(s->nc.info_str, sizeof(s->nc.info_str),
 647              "socket: mcast=%s:%d",
 648              inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
 649     return 0;
 650
 651 }
 652
 653 static int net_socket_udp_init(NetClientState *peer,
 654                                  const char *model,
 655                                  const char *name,
 656                                  const char *rhost,
 657                                  const char *lhost,
 658                                  Error **errp)
 659 {
 660     NetSocketState *s;
 661     int fd, ret;
 662     struct sockaddr_in laddr, raddr;
 663
 664     if (parse_host_port(&laddr, lhost, errp) < 0) {
 665         return -1;
 666     }
 667
 668     if (parse_host_port(&raddr, rhost, errp) < 0) {
 669         return -1;
 670     }
 671
 672     fd = qemu_socket(PF_INET, SOCK_DGRAM, 0);
 673     if (fd < 0) {
 674         error_setg_errno(errp, errno, "can't create datagram socket");
 675         return -1;
 676     }
 677
 678     ret = socket_set_fast_reuse(fd);
 679     if (ret < 0) {
 680         error_setg_errno(errp, errno,
 681                          "can't set socket option SO_REUSEADDR");
 682         closesocket(fd);
 683         return -1;
 684     }
 685     ret = bind(fd, (struct sockaddr *)&laddr, sizeof(laddr));
 686     if (ret < 0) {
 687         error_setg_errno(errp, errno, "can't bind ip=%s to socket",
 688                          inet_ntoa(laddr.sin_addr));
 689         closesocket(fd);
 690         return -1;
 691     }
 692     qemu_set_nonblock(fd);
 693
 694     s = net_socket_fd_init(peer, model, name, fd, 0, NULL, errp);
 695     if (!s) {
 696         return -1;
 697     }
 698
 699     s->dgram_dst = raddr;
 700
 701     snprintf(s->nc.info_str, sizeof(s->nc.info_str),
 702              "socket: udp=%s:%d",
 703              inet_ntoa(raddr.sin_addr), ntohs(raddr.sin_port));
 704     return 0;
 705 }
 706
 707 int net_init_socket(const Netdev *netdev, const char *name,
 708                     NetClientState *peer, Error **errp)
 709 {
 710     const NetdevSocketOptions *sock;
 711
 712     assert(netdev->type == NET_CLIENT_DRIVER_SOCKET);
 713     sock = &netdev->u.socket;
 714
 715     if (sock->has_fd + sock->has_listen + sock->has_connect + sock->has_mcast +
 716         sock->has_udp != 1) {
 717         error_setg(errp, "exactly one of listen=, connect=, mcast= or udp="
 718                    " is required");
 719         return -1;
 720     }
 721
 722     if (sock->has_localaddr && !sock->has_mcast && !sock->has_udp) {
 723         error_setg(errp, "localaddr= is only valid with mcast= or udp=");
 724         return -1;
 725     }
 726
 727     if (sock->has_fd) {
 728         int fd, ret;
 729
 730         fd = monitor_fd_param(monitor_cur(), sock->fd, errp);
 731         if (fd == -1) {
 732             return -1;
 733         }
 734         ret = qemu_try_set_nonblock(fd);
 735         if (ret < 0) {
 736             error_setg_errno(errp, -ret, "%s: Can't use file descriptor %d",
 737                              name, fd);
 738             return -1;
 739         }
 740         if (!net_socket_fd_init(peer, "socket", name, fd, 1, sock->mcast,
 741                                 errp)) {
 742             return -1;
 743         }
 744         return 0;
 745     }
 746
 747     if (sock->has_listen) {
 748         if (net_socket_listen_init(peer, "socket", name, sock->listen, errp)
 749             < 0) {
 750             return -1;
 751         }
 752         return 0;
 753     }
 754
 755     if (sock->has_connect) {
 756         if (net_socket_connect_init(peer, "socket", name, sock->connect, errp)
 757             < 0) {
 758             return -1;
 759         }
 760         return 0;
 761     }
 762
 763     if (sock->has_mcast) {
 764         /* if sock->localaddr is missing, it has been initialized to "all bits
 765          * zero" */
 766         if (net_socket_mcast_init(peer, "socket", name, sock->mcast,
 767                                   sock->localaddr, errp) < 0) {
 768             return -1;
 769         }
 770         return 0;
 771     }
 772
 773     assert(sock->has_udp);
 774     if (!sock->has_localaddr) {
 775         error_setg(errp, "localaddr= is mandatory with udp=");
 776         return -1;
 777     }
 778     if (net_socket_udp_init(peer, "socket", name, sock->udp, sock->localaddr,
 779                             errp) < 0) {
 780         return -1;
 781     }
 782     return 0;
 783 }