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