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