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 "config-host.h"
  25
  26 #include "net/net.h"
  27 #include "clients.h"
  28 #include "monitor/monitor.h"
  29 #include "qemu-common.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     int state; /* 0 = getting length, 1 = getting data */
  41     unsigned int index;
  42     unsigned int packet_len;
  43     unsigned int send_index;      /* number of bytes sent (only SOCK_STREAM) */
  44     uint8_t buf[NET_BUFSIZE];
  45     struct sockaddr_in dgram_dst; /* contains inet host and port destination iff connectionless (SOCK_DGRAM) */
  46     IOHandler *send_fn;           /* differs between SOCK_STREAM/SOCK_DGRAM */
  47     bool read_poll;               /* waiting to receive data? */
  48     bool write_poll;              /* waiting to transmit data? */
  49 } NetSocketState;
  50
  51 static void net_socket_accept(void *opaque);
  52 static void net_socket_writable(void *opaque);
  53
  54 static void net_socket_update_fd_handler(NetSocketState *s)
  55 {
  56     qemu_set_fd_handler(s->fd,
  57                         s->read_poll ? s->send_fn : NULL,
  58                         s->write_poll ? net_socket_writable : NULL,
  59                         s);
  60 }
  61
  62 static void net_socket_read_poll(NetSocketState *s, bool enable)
  63 {
  64     s->read_poll = enable;
  65     net_socket_update_fd_handler(s);
  66 }
  67
  68 static void net_socket_write_poll(NetSocketState *s, bool enable)
  69 {
  70     s->write_poll = enable;
  71     net_socket_update_fd_handler(s);
  72 }
  73
  74 static void net_socket_writable(void *opaque)
  75 {
  76     NetSocketState *s = opaque;
  77
  78     net_socket_write_poll(s, false);
  79
  80     qemu_flush_queued_packets(&s->nc);
  81 }
  82
  83 static ssize_t net_socket_receive(NetClientState *nc, const uint8_t *buf, size_t size)
  84 {
  85     NetSocketState *s = DO_UPCAST(NetSocketState, nc, nc);
  86     uint32_t len = htonl(size);
  87     struct iovec iov[] = {
  88         {
  89             .iov_base = &len,
  90             .iov_len  = sizeof(len),
  91         }, {
  92             .iov_base = (void *)buf,
  93             .iov_len  = size,
  94         },
  95     };
  96     size_t remaining;
  97     ssize_t ret;
  98
  99     remaining = iov_size(iov, 2) - s->send_index;
 100     ret = iov_send(s->fd, iov, 2, s->send_index, remaining);
 101
 102     if (ret == -1 && errno == EAGAIN) {
 103         ret = 0; /* handled further down */
 104     }
 105     if (ret == -1) {
 106         s->send_index = 0;
 107         return -errno;
 108     }
 109     if (ret < (ssize_t)remaining) {
 110         s->send_index += ret;
 111         net_socket_write_poll(s, true);
 112         return 0;
 113     }
 114     s->send_index = 0;
 115     return size;
 116 }
 117
 118 static ssize_t net_socket_receive_dgram(NetClientState *nc, const uint8_t *buf, size_t size)
 119 {
 120     NetSocketState *s = DO_UPCAST(NetSocketState, nc, nc);
 121     ssize_t ret;
 122
 123     do {
 124         ret = qemu_sendto(s->fd, buf, size, 0,
 125                           (struct sockaddr *)&s->dgram_dst,
 126                           sizeof(s->dgram_dst));
 127     } while (ret == -1 && errno == EINTR);
 128
 129     if (ret == -1 && errno == EAGAIN) {
 130         net_socket_write_poll(s, true);
 131         return 0;
 132     }
 133     return ret;
 134 }
 135
 136 static void net_socket_send_completed(NetClientState *nc, ssize_t len)
 137 {
 138     NetSocketState *s = DO_UPCAST(NetSocketState, nc, nc);
 139
 140     if (!s->read_poll) {
 141         net_socket_read_poll(s, true);
 142     }
 143 }
 144
 145 static void net_socket_send(void *opaque)
 146 {
 147     NetSocketState *s = opaque;
 148     int size, err;
 149     unsigned l;
 150     uint8_t buf1[NET_BUFSIZE];
 151     const uint8_t *buf;
 152
 153     size = qemu_recv(s->fd, buf1, sizeof(buf1), 0);
 154     if (size < 0) {
 155         err = socket_error();
 156         if (err != EWOULDBLOCK)
 157             goto eoc;
 158     } else if (size == 0) {
 159         /* end of connection */
 160     eoc:
 161         net_socket_read_poll(s, false);
 162         net_socket_write_poll(s, false);
 163         if (s->listen_fd != -1) {
 164             qemu_set_fd_handler(s->listen_fd, net_socket_accept, NULL, s);
 165         }
 166         closesocket(s->fd);
 167
 168         s->fd = -1;
 169         s->state = 0;
 170         s->index = 0;
 171         s->packet_len = 0;
 172         s->nc.link_down = true;
 173         memset(s->buf, 0, sizeof(s->buf));
 174         memset(s->nc.info_str, 0, sizeof(s->nc.info_str));
 175
 176         return;
 177     }
 178     buf = buf1;
 179     while (size > 0) {
 180         /* reassemble a packet from the network */
 181         switch(s->state) {
 182         case 0:
 183             l = 4 - s->index;
 184             if (l > size)
 185                 l = size;
 186             memcpy(s->buf + s->index, buf, l);
 187             buf += l;
 188             size -= l;
 189             s->index += l;
 190             if (s->index == 4) {
 191                 /* got length */
 192                 s->packet_len = ntohl(*(uint32_t *)s->buf);
 193                 s->index = 0;
 194                 s->state = 1;
 195             }
 196             break;
 197         case 1:
 198             l = s->packet_len - s->index;
 199             if (l > size)
 200                 l = size;
 201             if (s->index + l <= sizeof(s->buf)) {
 202                 memcpy(s->buf + s->index, buf, l);
 203             } else {
 204                 fprintf(stderr, "serious error: oversized packet received,"
 205                     "connection terminated.\n");
 206                 s->state = 0;
 207                 goto eoc;
 208             }
 209
 210             s->index += l;
 211             buf += l;
 212             size -= l;
 213             if (s->index >= s->packet_len) {
 214                 s->index = 0;
 215                 s->state = 0;
 216                 if (qemu_send_packet_async(&s->nc, s->buf, s->packet_len,
 217                                            net_socket_send_completed) == 0) {
 218                     net_socket_read_poll(s, false);
 219                     break;
 220                 }
 221             }
 222             break;
 223         }
 224     }
 225 }
 226
 227 static void net_socket_send_dgram(void *opaque)
 228 {
 229     NetSocketState *s = opaque;
 230     int size;
 231
 232     size = qemu_recv(s->fd, s->buf, sizeof(s->buf), 0);
 233     if (size < 0)
 234         return;
 235     if (size == 0) {
 236         /* end of connection */
 237         net_socket_read_poll(s, false);
 238         net_socket_write_poll(s, false);
 239         return;
 240     }
 241     if (qemu_send_packet_async(&s->nc, s->buf, size,
 242                                net_socket_send_completed) == 0) {
 243         net_socket_read_poll(s, false);
 244     }
 245 }
 246
 247 static int net_socket_mcast_create(struct sockaddr_in *mcastaddr, struct in_addr *localaddr)
 248 {
 249     struct ip_mreq imr;
 250     int fd;
 251     int val, ret;
 252 #ifdef __OpenBSD__
 253     unsigned char loop;
 254 #else
 255     int loop;
 256 #endif
 257
 258     if (!IN_MULTICAST(ntohl(mcastaddr->sin_addr.s_addr))) {
 259         fprintf(stderr, "qemu: error: specified mcastaddr \"%s\" (0x%08x) "
 260                 "does not contain a multicast address\n",
 261                 inet_ntoa(mcastaddr->sin_addr),
 262                 (int)ntohl(mcastaddr->sin_addr.s_addr));
 263         return -1;
 264
 265     }
 266     fd = qemu_socket(PF_INET, SOCK_DGRAM, 0);
 267     if (fd < 0) {
 268         perror("socket(PF_INET, SOCK_DGRAM)");
 269         return -1;
 270     }
 271
 272     /* Allow multiple sockets to bind the same multicast ip and port by setting
 273      * SO_REUSEADDR. This is the only situation where SO_REUSEADDR should be set
 274      * on windows. Use socket_set_fast_reuse otherwise as it sets SO_REUSEADDR
 275      * only on posix systems.
 276      */
 277     val = 1;
 278     ret = qemu_setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
 279     if (ret < 0) {
 280         perror("setsockopt(SOL_SOCKET, SO_REUSEADDR)");
 281         goto fail;
 282     }
 283
 284     ret = bind(fd, (struct sockaddr *)mcastaddr, sizeof(*mcastaddr));
 285     if (ret < 0) {
 286         perror("bind");
 287         goto fail;
 288     }
 289
 290     /* Add host to multicast group */
 291     imr.imr_multiaddr = mcastaddr->sin_addr;
 292     if (localaddr) {
 293         imr.imr_interface = *localaddr;
 294     } else {
 295         imr.imr_interface.s_addr = htonl(INADDR_ANY);
 296     }
 297
 298     ret = qemu_setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
 299                           &imr, sizeof(struct ip_mreq));
 300     if (ret < 0) {
 301         perror("setsockopt(IP_ADD_MEMBERSHIP)");
 302         goto fail;
 303     }
 304
 305     /* Force mcast msgs to loopback (eg. several QEMUs in same host */
 306     loop = 1;
 307     ret = qemu_setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP,
 308                           &loop, sizeof(loop));
 309     if (ret < 0) {
 310         perror("setsockopt(SOL_IP, IP_MULTICAST_LOOP)");
 311         goto fail;
 312     }
 313
 314     /* If a bind address is given, only send packets from that address */
 315     if (localaddr != NULL) {
 316         ret = qemu_setsockopt(fd, IPPROTO_IP, IP_MULTICAST_IF,
 317                               localaddr, sizeof(*localaddr));
 318         if (ret < 0) {
 319             perror("setsockopt(IP_MULTICAST_IF)");
 320             goto fail;
 321         }
 322     }
 323
 324     qemu_set_nonblock(fd);
 325     return fd;
 326 fail:
 327     if (fd >= 0)
 328         closesocket(fd);
 329     return -1;
 330 }
 331
 332 static void net_socket_cleanup(NetClientState *nc)
 333 {
 334     NetSocketState *s = DO_UPCAST(NetSocketState, nc, nc);
 335     if (s->fd != -1) {
 336         net_socket_read_poll(s, false);
 337         net_socket_write_poll(s, false);
 338         close(s->fd);
 339         s->fd = -1;
 340     }
 341     if (s->listen_fd != -1) {
 342         qemu_set_fd_handler(s->listen_fd, NULL, NULL, NULL);
 343         closesocket(s->listen_fd);
 344         s->listen_fd = -1;
 345     }
 346 }
 347
 348 static NetClientInfo net_dgram_socket_info = {
 349     .type = NET_CLIENT_OPTIONS_KIND_SOCKET,
 350     .size = sizeof(NetSocketState),
 351     .receive = net_socket_receive_dgram,
 352     .cleanup = net_socket_cleanup,
 353 };
 354
 355 static NetSocketState *net_socket_fd_init_dgram(NetClientState *peer,
 356                                                 const char *model,
 357                                                 const char *name,
 358                                                 int fd, int is_connected)
 359 {
 360     struct sockaddr_in saddr;
 361     int newfd;
 362     socklen_t saddr_len = sizeof(saddr);
 363     NetClientState *nc;
 364     NetSocketState *s;
 365
 366     /* fd passed: multicast: "learn" dgram_dst address from bound address and save it
 367      * Because this may be "shared" socket from a "master" process, datagrams would be recv()
 368      * by ONLY ONE process: we must "clone" this dgram socket --jjo
 369      */
 370
 371     if (is_connected) {
 372         if (getsockname(fd, (struct sockaddr *) &saddr, &saddr_len) == 0) {
 373             /* must be bound */
 374             if (saddr.sin_addr.s_addr == 0) {
 375                 fprintf(stderr, "qemu: error: init_dgram: fd=%d unbound, "
 376                         "cannot setup multicast dst addr\n", fd);
 377                 goto err;
 378             }
 379             /* clone dgram socket */
 380             newfd = net_socket_mcast_create(&saddr, NULL);
 381             if (newfd < 0) {
 382                 /* error already reported by net_socket_mcast_create() */
 383                 goto err;
 384             }
 385             /* clone newfd to fd, close newfd */
 386             dup2(newfd, fd);
 387             close(newfd);
 388
 389         } else {
 390             fprintf(stderr,
 391                     "qemu: error: init_dgram: fd=%d failed getsockname(): %s\n",
 392                     fd, strerror(errno));
 393             goto err;
 394         }
 395     }
 396
 397     nc = qemu_new_net_client(&net_dgram_socket_info, peer, model, name);
 398
 399     s = DO_UPCAST(NetSocketState, nc, nc);
 400
 401     s->fd = fd;
 402     s->listen_fd = -1;
 403     s->send_fn = net_socket_send_dgram;
 404     net_socket_read_poll(s, true);
 405
 406     /* mcast: save bound address as dst */
 407     if (is_connected) {
 408         s->dgram_dst = saddr;
 409         snprintf(nc->info_str, sizeof(nc->info_str),
 410                  "socket: fd=%d (cloned mcast=%s:%d)",
 411                  fd, inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
 412     } else {
 413         snprintf(nc->info_str, sizeof(nc->info_str),
 414                  "socket: fd=%d", fd);
 415     }
 416
 417     return s;
 418
 419 err:
 420     closesocket(fd);
 421     return NULL;
 422 }
 423
 424 static void net_socket_connect(void *opaque)
 425 {
 426     NetSocketState *s = opaque;
 427     s->send_fn = net_socket_send;
 428     net_socket_read_poll(s, true);
 429 }
 430
 431 static NetClientInfo net_socket_info = {
 432     .type = NET_CLIENT_OPTIONS_KIND_SOCKET,
 433     .size = sizeof(NetSocketState),
 434     .receive = net_socket_receive,
 435     .cleanup = net_socket_cleanup,
 436 };
 437
 438 static NetSocketState *net_socket_fd_init_stream(NetClientState *peer,
 439                                                  const char *model,
 440                                                  const char *name,
 441                                                  int fd, int is_connected)
 442 {
 443     NetClientState *nc;
 444     NetSocketState *s;
 445
 446     nc = qemu_new_net_client(&net_socket_info, peer, model, name);
 447
 448     snprintf(nc->info_str, sizeof(nc->info_str), "socket: fd=%d", fd);
 449
 450     s = DO_UPCAST(NetSocketState, nc, nc);
 451
 452     s->fd = fd;
 453     s->listen_fd = -1;
 454
 455     /* Disable Nagle algorithm on TCP sockets to reduce latency */
 456     socket_set_nodelay(fd);
 457
 458     if (is_connected) {
 459         net_socket_connect(s);
 460     } else {
 461         qemu_set_fd_handler(s->fd, NULL, net_socket_connect, s);
 462     }
 463     return s;
 464 }
 465
 466 static NetSocketState *net_socket_fd_init(NetClientState *peer,
 467                                           const char *model, const char *name,
 468                                           int fd, int is_connected)
 469 {
 470     int so_type = -1, optlen=sizeof(so_type);
 471
 472     if(getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&so_type,
 473         (socklen_t *)&optlen)< 0) {
 474         fprintf(stderr, "qemu: error: getsockopt(SO_TYPE) for fd=%d failed\n",
 475                 fd);
 476         closesocket(fd);
 477         return NULL;
 478     }
 479     switch(so_type) {
 480     case SOCK_DGRAM:
 481         return net_socket_fd_init_dgram(peer, model, name, fd, is_connected);
 482     case SOCK_STREAM:
 483         return net_socket_fd_init_stream(peer, model, name, fd, is_connected);
 484     default:
 485         /* who knows ... this could be a eg. a pty, do warn and continue as stream */
 486         fprintf(stderr, "qemu: warning: socket type=%d for fd=%d is not SOCK_DGRAM or SOCK_STREAM\n", so_type, fd);
 487         return net_socket_fd_init_stream(peer, model, name, fd, is_connected);
 488     }
 489     return NULL;
 490 }
 491
 492 static void net_socket_accept(void *opaque)
 493 {
 494     NetSocketState *s = opaque;
 495     struct sockaddr_in saddr;
 496     socklen_t len;
 497     int fd;
 498
 499     for(;;) {
 500         len = sizeof(saddr);
 501         fd = qemu_accept(s->listen_fd, (struct sockaddr *)&saddr, &len);
 502         if (fd < 0 && errno != EINTR) {
 503             return;
 504         } else if (fd >= 0) {
 505             qemu_set_fd_handler(s->listen_fd, NULL, NULL, NULL);
 506             break;
 507         }
 508     }
 509
 510     s->fd = fd;
 511     s->nc.link_down = false;
 512     net_socket_connect(s);
 513     snprintf(s->nc.info_str, sizeof(s->nc.info_str),
 514              "socket: connection from %s:%d",
 515              inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
 516 }
 517
 518 static int net_socket_listen_init(NetClientState *peer,
 519                                   const char *model,
 520                                   const char *name,
 521                                   const char *host_str)
 522 {
 523     NetClientState *nc;
 524     NetSocketState *s;
 525     struct sockaddr_in saddr;
 526     int fd, ret;
 527
 528     if (parse_host_port(&saddr, host_str) < 0)
 529         return -1;
 530
 531     fd = qemu_socket(PF_INET, SOCK_STREAM, 0);
 532     if (fd < 0) {
 533         perror("socket");
 534         return -1;
 535     }
 536     qemu_set_nonblock(fd);
 537
 538     socket_set_fast_reuse(fd);
 539
 540     ret = bind(fd, (struct sockaddr *)&saddr, sizeof(saddr));
 541     if (ret < 0) {
 542         perror("bind");
 543         closesocket(fd);
 544         return -1;
 545     }
 546     ret = listen(fd, 0);
 547     if (ret < 0) {
 548         perror("listen");
 549         closesocket(fd);
 550         return -1;
 551     }
 552
 553     nc = qemu_new_net_client(&net_socket_info, peer, model, name);
 554     s = DO_UPCAST(NetSocketState, nc, nc);
 555     s->fd = -1;
 556     s->listen_fd = fd;
 557     s->nc.link_down = true;
 558
 559     qemu_set_fd_handler(s->listen_fd, net_socket_accept, NULL, s);
 560     return 0;
 561 }
 562
 563 static int net_socket_connect_init(NetClientState *peer,
 564                                    const char *model,
 565                                    const char *name,
 566                                    const char *host_str)
 567 {
 568     NetSocketState *s;
 569     int fd, connected, ret, err;
 570     struct sockaddr_in saddr;
 571
 572     if (parse_host_port(&saddr, host_str) < 0)
 573         return -1;
 574
 575     fd = qemu_socket(PF_INET, SOCK_STREAM, 0);
 576     if (fd < 0) {
 577         perror("socket");
 578         return -1;
 579     }
 580     qemu_set_nonblock(fd);
 581
 582     connected = 0;
 583     for(;;) {
 584         ret = connect(fd, (struct sockaddr *)&saddr, sizeof(saddr));
 585         if (ret < 0) {
 586             err = socket_error();
 587             if (err == EINTR || err == EWOULDBLOCK) {
 588             } else if (err == EINPROGRESS) {
 589                 break;
 590 #ifdef _WIN32
 591             } else if (err == WSAEALREADY || err == WSAEINVAL) {
 592                 break;
 593 #endif
 594             } else {
 595                 perror("connect");
 596                 closesocket(fd);
 597                 return -1;
 598             }
 599         } else {
 600             connected = 1;
 601             break;
 602         }
 603     }
 604     s = net_socket_fd_init(peer, model, name, fd, connected);
 605     if (!s)
 606         return -1;
 607     snprintf(s->nc.info_str, sizeof(s->nc.info_str),
 608              "socket: connect to %s:%d",
 609              inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
 610     return 0;
 611 }
 612
 613 static int net_socket_mcast_init(NetClientState *peer,
 614                                  const char *model,
 615                                  const char *name,
 616                                  const char *host_str,
 617                                  const char *localaddr_str)
 618 {
 619     NetSocketState *s;
 620     int fd;
 621     struct sockaddr_in saddr;
 622     struct in_addr localaddr, *param_localaddr;
 623
 624     if (parse_host_port(&saddr, host_str) < 0)
 625         return -1;
 626
 627     if (localaddr_str != NULL) {
 628         if (inet_aton(localaddr_str, &localaddr) == 0)
 629             return -1;
 630         param_localaddr = &localaddr;
 631     } else {
 632         param_localaddr = NULL;
 633     }
 634
 635     fd = net_socket_mcast_create(&saddr, param_localaddr);
 636     if (fd < 0)
 637         return -1;
 638
 639     s = net_socket_fd_init(peer, model, name, fd, 0);
 640     if (!s)
 641         return -1;
 642
 643     s->dgram_dst = saddr;
 644
 645     snprintf(s->nc.info_str, sizeof(s->nc.info_str),
 646              "socket: mcast=%s:%d",
 647              inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
 648     return 0;
 649
 650 }
 651
 652 static int net_socket_udp_init(NetClientState *peer,
 653                                  const char *model,
 654                                  const char *name,
 655                                  const char *rhost,
 656                                  const char *lhost)
 657 {
 658     NetSocketState *s;
 659     int fd, ret;
 660     struct sockaddr_in laddr, raddr;
 661
 662     if (parse_host_port(&laddr, lhost) < 0) {
 663         return -1;
 664     }
 665
 666     if (parse_host_port(&raddr, rhost) < 0) {
 667         return -1;
 668     }
 669
 670     fd = qemu_socket(PF_INET, SOCK_DGRAM, 0);
 671     if (fd < 0) {
 672         perror("socket(PF_INET, SOCK_DGRAM)");
 673         return -1;
 674     }
 675
 676     ret = socket_set_fast_reuse(fd);
 677     if (ret < 0) {
 678         closesocket(fd);
 679         return -1;
 680     }
 681     ret = bind(fd, (struct sockaddr *)&laddr, sizeof(laddr));
 682     if (ret < 0) {
 683         perror("bind");
 684         closesocket(fd);
 685         return -1;
 686     }
 687     qemu_set_nonblock(fd);
 688
 689     s = net_socket_fd_init(peer, model, name, fd, 0);
 690     if (!s) {
 691         return -1;
 692     }
 693
 694     s->dgram_dst = raddr;
 695
 696     snprintf(s->nc.info_str, sizeof(s->nc.info_str),
 697              "socket: udp=%s:%d",
 698              inet_ntoa(raddr.sin_addr), ntohs(raddr.sin_port));
 699     return 0;
 700 }
 701
 702 int net_init_socket(const NetClientOptions *opts, const char *name,
 703                     NetClientState *peer, Error **errp)
 704 {
 705     /* FIXME error_setg(errp, ...) on failure */
 706     Error *err = NULL;
 707     const NetdevSocketOptions *sock;
 708
 709     assert(opts->type == NET_CLIENT_OPTIONS_KIND_SOCKET);
 710     sock = opts->u.socket;
 711
 712     if (sock->has_fd + sock->has_listen + sock->has_connect + sock->has_mcast +
 713         sock->has_udp != 1) {
 714         error_report("exactly one of fd=, listen=, connect=, mcast= or udp="
 715                      " is required");
 716         return -1;
 717     }
 718
 719     if (sock->has_localaddr && !sock->has_mcast && !sock->has_udp) {
 720         error_report("localaddr= is only valid with mcast= or udp=");
 721         return -1;
 722     }
 723
 724     if (sock->has_fd) {
 725         int fd;
 726
 727         fd = monitor_fd_param(cur_mon, sock->fd, &err);
 728         if (fd == -1) {
 729             error_report_err(err);
 730             return -1;
 731         }
 732         qemu_set_nonblock(fd);
 733         if (!net_socket_fd_init(peer, "socket", name, fd, 1)) {
 734             return -1;
 735         }
 736         return 0;
 737     }
 738
 739     if (sock->has_listen) {
 740         if (net_socket_listen_init(peer, "socket", name, sock->listen) == -1) {
 741             return -1;
 742         }
 743         return 0;
 744     }
 745
 746     if (sock->has_connect) {
 747         if (net_socket_connect_init(peer, "socket", name, sock->connect) ==
 748             -1) {
 749             return -1;
 750         }
 751         return 0;
 752     }
 753
 754     if (sock->has_mcast) {
 755         /* if sock->localaddr is missing, it has been initialized to "all bits
 756          * zero" */
 757         if (net_socket_mcast_init(peer, "socket", name, sock->mcast,
 758             sock->localaddr) == -1) {
 759             return -1;
 760         }
 761         return 0;
 762     }
 763
 764     assert(sock->has_udp);
 765     if (!sock->has_localaddr) {
 766         error_report("localaddr= is mandatory with udp=");
 767         return -1;
 768     }
 769     if (net_socket_udp_init(peer, "socket", name, sock->udp, sock->localaddr) ==
 770         -1) {
 771         return -1;
 772     }
 773     return 0;
 774 }